For Sarah Hall, every mealtime was dangerous.

She has a rare condition called cardioinhibitory syncope, which causes overactive nerve signals to tell the heart to stop beating in response to subconscious bodily processes, such as swallowing. Swallowing food caused Hall's heart to stop beating up to 12 times a day, often making her faint.

Hall's condition wasn't improving with any treatments, but an innovative procedure has changed her life, as well as the lives of dozens of others.

In work presented at the British Cardiovascular Society's annual conference, scientists reported that 25 people with the condition dramatically improved after an experimental procedure. The early findings, which have not been peer-reviewed yet, are promising but require validation.

"It's important to note that this is still a relatively new therapy and that larger studies and longer-term follow-ups are still needed to provide a better understanding of its durability and help identify which patients benefit most," said Dr. Sirisha Vadali, a cardiologist at HonorHealth who was not involved in the research.

When "rest and digest" goes haywire

The autonomic nervous system handles the electrical signals the body relies on to complete subconscious, everyday processes, like eating or sleeping. This includes the body's complementary "fight-or-flight" and "rest-and-digest" responses.

The latter system send the bulk of its signaling through the vagus nerve, which starts in the brainstem and extends through the chest and abdomen. As the body senses changes, like food entering the throat or the legs bending into a crouch, the vagus nerve updates the brain on what's happening, enabling it to subtly alter digestion, breathing and heart rate in response.

In some animals, vagal activation is involved in a more dramatic bodily process: hibernation. Hibernating mammals, like bears, experience a strong wave of signaling through the vagus nerve when they enter their winter den, which lowers their metabolic rate for weeks.

People with cardioinhibitory syncope "go into a hibernation response" because their vagus nerve signals are too strong, Dr. Boon Lim, a consultant cardiologist at Imperial College Healthcare NHS Trust who led the new work, told Live Science.

The vagus nerve transmits signals to the ganglionated plexi, a web of nerve endings on the surface of the heart. The signals then reach the body’s built-in system for maintaining heart rate — and when they're too strong, it briefly shortcircuits this system, causing the heart beat to pause entirely.

There are many ways this hyperactive vagal response can be triggered. For 50-year-old Hall, the trigger was swallowing, while for others with the condition, sudden abdominal pain can flip the switch.

Why we faint

Syncope, the medical term for fainting, is common. Lim estimates that 40% of people faint at some point in their lifetimes, and for most, it is because signals from the vagus nerve temporarily reduce their blood pressure. Without enough blood flowing to the brain, people briefly lose consciousness.

But in cardioinhibitory syncope, the heart pauses entirely for a few seconds due to hyperactive vagal signaling. The strength of the vagus nerve's signaling to the heart is determined largely by genetics. Fewer than 5% of people who seek treatment for syncope have cardioinhibitory syncope.

The condition generally isn't life-threatening, Vadali said, but its unpredictability is highly disruptive. "Many patients may experience anxiety about when the next episode might occur," she said.

Boon described a patient named Rob, who had reported frequent fainting episodes. A diagram tracking the waves of Rob's pulse on a normal afternoon showed the churning rhythm of his heartbeat becoming still ‪—‬ one of several daily episodes. "It suddenly pauses for close to five seconds for no reason," Lim said.

For people with cardioinhibitory syncope, the best option previously had been to have a pacemaker implanted, Lim said. But this isn't a permanent solution; pacemaker batteries need to be replaced every decade or so. Patients who get pacemakers at younger ages can face long-term health risks as the devices deteriorate, and battery replacement operations can cause infections.

Now, Lim and colleagues have shown that a procedure called cardioneuroablation could drastically improve the lives of patients like Rob.

In the procedure, Lim snaked a thin wire through Rob's body that eventually reached his heart, specifically the ganglionated plexi on the organ's surface. Lim then delivered a pulse of radio-frequency energy to the plexi, which destroyed the tissue, thus reducing disruption of the heart's built-in pacemaker.

Lim's team carried out the procedure on 25 people at Imperial College London between 2013 and 2023. On average, the patients had had fewer than one fainting episode in the following year. This translated to significant improvements in the patients' quality of life, they reported.

Three patients required additional procedures, because the ganglionated plexi can sometimes regrow. The procedure is fairly invasive, but compared to repeated pacemaker maintenance, it could still offer a more appealing solution to patients, the researchers say.

By now, Lim's team has used cardioneuroablation to treat 52 people. Vadali said the early data presented at the conference is promising but more research is needed to see how well its effects last.

For Hall, the procedure changed her life. She has not fainted since, even at mealtimes.

"I can drive; I can work," she said in a statement. "It feels like everything has come full-circle."

What do you know about the body's hardest-working muscle? Find out with our heart quiz!

The 4,000-year-old skull of a Bronze Age child buried in what's now Uzbekistan bears scars from a cranial surgery known as trepanation. It is the oldest documented evidence of surgery in Central Asia and one of the oldest examples of surgery in all of Asia, the researchers report.

The skeleton of the child, who died at about age 5, was unearthed in April. The body had been buried in a single grave alongside the body of a child who died at about 3 years old, researchers said in a translated statement.

The 5-year-old's skull has "clear signs of cranial trepanation" involving stone or bone tools, according to the statement. Trepanation was commonly performed in ancient times, perhaps in attempts to treat maladies like epilepsy, migraines or behavioral problems. But the researchers noted that the "frontier between medicine and ritual" would have been far less defined at that time than it is now.

A research team from Italy and Uzbekistan made the discovery in the Northern Bactria region, near the border with Afghanistan.

Ancient Oxus

The excavations focused on the site of the prehistoric settlement of Djarkutan, and the researchers dated the grave to the late third millennium B.C. At that time, Djarkutan was an urban center of the Oxus civilization, an Early Bronze Age culture that dominated Central Asia from about 2500 to 1500 B.C. The ongoing project to investigate the site and other aspects of the Oxus civilization began in 2024.

Archaeologists sometimes call the Oxus civilization the Bactria-Margiana Archaeological Complex, or BMAC. It was centered along rivers and in oases in the region, and it is renowned for its advanced agricultural economy and rich material culture. The demise of the Oxus civilization is thought to have been triggered by climatic changes that caused important rivers to dry up.

While evidence of ancient trepanations is relatively common in some places, the fact that this surgery was performed on a young child is perplexing, the researchers said.

"Djarkutan continues to surprise us," Enrico Ascalone, an archaeologist at the University of Salento who led the excavation, said in the statement. "A cranial trepanation on a child, four thousand years ago, in Central Asia: until yesterday it was unthinkable. Today it is in our data."

Yet the discovery also leaves mysteries. "Which group of 'specialists' within the town could have practiced such an intervention? What anatomical and surgical knowledge did such an operation presuppose? And why a five-year-old?" the team wrote in the statement. They hope to answer those questions in further investigations in the coming months.

At the Alcor facility in Arizona, more than 150 disembodied heads reportedly lie in cryogenic chambers, preserved in hopes that future medical advances can bring these brains back to life in new bodies. Given that scientists still cannot revive a cryogenically preserved brain, why do patients bother with cryonics at all? Why couldn't these heads just be stitched onto new bodies in the present day, when they're still fresh? In other words, why isn't a brain transplant possible?

Dr. Max Krucoff, an assistant professor of neurosurgery at the Medical College of Wisconsin, would rather describe such a procedure as a body transplant. Unlike a patient who receives a donor heart or liver, transplanting a brain into a patient's body would make them "a completely new human being," he told Live Science. "Your agency, your identity, is contained within your brain."

Semantics aside, Krucoff said this transplant is currently impossible because surgeons cannot yet forge signaling connections between nerves in the central nervous system, which includes the brain and spinal cord. Transplanted peripheral nerves, or the nerves that branch off throughout the body beyond the brain and spinal cord, can eventually communicate with their new neighbors, since these nerve cells can regenerate. There is less evidence that the adult human central nervous system can generate fresh neurons, and if it does, it's to a limited degree. Neurons can form new connections throughout a person's lifetime, which is how learning is encoded, but scientists do not understand this pathway well enough to exploit it for a transplant.

Even a partial brain transplant, such as a cerebellum swap, is out of the question for now. In the case of the cerebellum, the structure is home to millions of specialized neurons called Purkinje cells, each of which receives signals from thousands of other neurons. "The number of connections is exponential," Krucoff said. "That's way beyond our capacity."

Fusing brain and body at the spinal cord would be the simplest theoretical brain transplant, since connections between spinal nerves are more straightforward than neurons in the brain. The surgeon performing this head transplant could connect the skin, muscle, vessels and bones in the neck, and even align the nerves of the spinal cord, "but to get those cells to communicate, we just haven't figured out how to do that yet," Krucoff said.

Has a brain transplant ever been attempted?

Scientists began attempting head transplants on animals with the advent of new blood vessel suturing techniques in the early 1900s. Most of the dogs and monkeys involved in those experiments survived a few days at most, as researchers struggled to create a working vascular system or to manage host rejection of the transplanted head with immunosuppressive agents.

Starting in 1970, Dr. Robert J. White transplanted the heads of monkeys onto new host bodies. The animals could chew and swallow food after surgery, and postsurgical electroencephalogram readouts suggested that their brains were awake, though none survived more than nine days.

Inspired by this work, Italian surgeon Dr. Sergio Canavero laid out his vision for the first human head transplant in 2013, attracting widespread pushback from colleagues on ethical and scientific grounds. Canavero's 2017 announcement that he had performed the first head transplant on a human cadaver was described at the time as "the continuation of a despicable fraud" by New York University bioethicist Arthur Caplan, who pointed out the likelihood of immune rejection and the challenge of linking a brain with all-new nervous inputs.

Can any tissue be transplanted into the central nervous system?

Although a surgeon can't switch one brain out for another, stem cell or organoid grafts could one day replenish damaged or diseased brain tissue.

Stem cells programmed to develop into neurons may have better odds of integrating into existing circuitry than mature neurons do, said Ruslan Rust, an assistant professor of research physiology and neuroscience at the University of Southern California Keck School of Medicine.

Ideally, these stem cells could be derived from the patient's own tissue, to lower the odds of immune rejection, but standardized donor cell lines reduce the need for quality control on individual tissue samples. In this way, neurons originating from one person's tissue could populate another person's brain.

Stem cell therapies have been tested in clinical trials for Parkinson's disease, stroke, spinal cord injury and epilepsy, but none of these treatments for these conditions are approved by the U.S. Food and Drug Administration for commercial use.

Rust told Live Science that future research will need to address the potential risks of these techniques, such as incompletely differentiated stem cells forming a tumor after transplant, or cells that do become neurons disrupting signaling pathways.

"The billion dollar question is, how do we make [transplanted cells] the cells that we want them to be, and how do we make sure that they integrate into those local circuitries where we want them to go?" he said.

Stem cells are also used to create lab-grown models of nervous tissues, called organoids, that can be transplanted into the brain. A 2023 study reported that human brain organoids could repair injured rat cortex, though therapies based on organoid transplant are still years away. Rust said such procedures could be more invasive than transplanting individual stem cells, and would need to account for vascular supply to the new tissue.

See how much you know about the most complex organ in the human body with our brain quiz!

Doctors had little hope for a fetus with a fatal lung condition, but at his parents' urging, they performed an unprecedentedly early operation during which they partially removed him from the womb.

The procedure saved the child's life — baby Cassian was born in August 2025 and is still doing well. The doctors hope the same approach will save others in the future.

The diagnosis came during a second-trimester ultrasound at Orlando Health Winnie Palmer Hospital for Women & Babies in Florida. The scan revealed overinflated lungs and a compressed heart — signs of a dangerous condition called congenital high airway obstruction syndrome (CHAOS).

Normally, developing lungs make secretions that travel up the windpipe and are swallowed. In CHAOS, a blockage in the windpipe stops the secretions from traveling up and out of the lungs, causing the organs to swell and compress the heart.

CHAOS affects just 1 in 50,000 pregnancies, and without treatment, the condition is fatal.

"Due to the relative infrequency of the condition, there is not a single, well-established standard of care for treatment," Dr. Cole Greves, one of Cassian's surgeons, told Live Science in an email. "Many cases must be individualized to the unique circumstances of the maternal and fetal patients."

A risky strategy

A scope revealed that the blockage in Cassian's widepipe was a 0.2-inch-thick (5 millimeters) membrane, which was too large to puncture using a minimally invasive laser probe.

Doctors have a method for safely delivering babies with these types of airway obstructions. Ideally, they wait until weeks 37 to 39 of pregnancy before using a variant of a cesarean section that involves delivering the head, neck and shoulders of the fetus first while the lower body remains in the womb. At this point, the baby is effectively half born.

Doctors then insert a catheter to bypass the blockage, drain the fluid and allow the baby to breathe, before clamping the umbilical cord and delivering the baby completely. This procedure, called the ex-utero intrapartum treatment (ExIT), is routinely performed on patients with CHAOS.

However, 1 in 4 fetuses with CHAOS die of heart failure before reaching those final weeks of pregnancy, said Dr. Emanuel Vlastos, another one of Cassian's fetal surgeons. This scenario seemed probable for Cassian, whose heart couldn't grow properly under the pressure of his distended lungs.

Cassian's parents urged doctors to try anything they could, leading the medical team to propose a potentially risky operation. At just 25 weeks, they would perform the ExIT, drain Cassian's lungs of fluid before his heart condition worsened, and place him back in the womb to continue developing.

"When you hear the parents say something to the effect of, 'Well, we know this may not work out, but if you can learn something and help another child, it's probably going to be worthwhile' — that's a pretty magnanimous thing for a parent to say, knowing their baby may die," Vlastos said.

With permission from an ethics committee, the surgeons operated on Cassian and his mother Keishera at 25 weeks of pregnancy. This involved conducting a C-section to expose Cassian's head and neck and then inserting a catheter into his windpipe to drain his lung secretions. Then, they returned his upper body into the womb and closed it. The catheter remained, held firmly in place by an inflated balloon in his windpipe, for the remainder of the pregnancy.

Given that the ExIT is typically performed at the time of child birth, this may be the first time doctors inserted a windpipe catheter into a fetus this early in gestation and returned him to the uterus, Greves said.

Balancing two lives

Operating on a fetus requires factoring in the mother's health, too.

"It is a tightrope walk, sometimes for several hours, while two lives hang in the balance," Greves said.

In this case, the team used general anesthesia to sedate mother and child, but doctors aren't sure what effects general anesthesia has on the developing nervous system of a 25-week fetus, Vlastos noted. Some studies suggest anesthesia can disrupt the formation of links between nerve cells and lead to cognitive issues, for example.

But it was imperative to sedate the fetus so he wouldn't attempt to breathe once exposed to air. "There's a whole lot of circulatory changes that potentially could happen if the baby tried to breathe," Vlastos said. And those changes could make it impossible to carry out the rest of the pregnancy.

Fetuses receive oxygen via the placenta rather than by breathing themselves; in the womb, a blood vessel called the ductus arteriosus forces oxygenated blood to bypass the immature lungs and directs it to the rest of the fetal body. "Once kids start to breathe outside of the womb, that vessel begins to slowly close" so that blood can travel to the lungs to pick up oxygen, Vlastos said. The doctors would not have been able to return Cassian to the womb if he had begun breathing.

For Cassian's mother Keishera, general anesthesia ensured that her uterine muscles relaxed during the procedure. Otherwise, "the baby's going to erupt" and be delivered early, Vlastos said, as the uterus is prone to contract when incised. What's more, a surgically opened uterus can expel a lot of blood if it starts contracting, leading to a potentially dangerous hemorrhage for the mother.

Another concern with operating on a preterm fetus is disrupting the delicate process of development. For example, if the balloon that held the catheter in place were underinflated, the catheter could have slid down and put pressure on the windpipe, preventing it from developing, Vlastos said. And if it were overinflated, the balloon could compress the blood vessels draining the head, causing circulatory issues, he added.

Inflating a balloon in the widepipe could pose a number of concerns, Dr. Diana Farmer, a fetal surgeon at the University of California, Davis Health who was not involved in this case, told Live Science in an email.

But "I like to say 'there's a lot we can do for a live patient,'" she said. "And the tracheal issues can be dealt with after birth."

The outcome

At week 31 of pregnancy, six weeks out from the daring surgery, Keishera's uterus started contracting and the time came to deliver baby Cassian. Scarring from the earlier surgery may have made her more likely to go into labor early.

A team of 30 people assembled at 3 a.m. to perform an ExIT, as had been planned, Vlastos said.

The team exposed Cassian's head and neck and swapped the fluid-draining catheter in the windpipe for an intubation tube to help the newborn breathe. He was born relatively healthy, although he needed to remain in the hospital for a few months due to being born prematurely.

Today, Cassian remains on a ventilator but is being weaned off respiratory support. When he's older, he'll require surgery to clear the obstruction in his windpipe and allow his breathing tube to be removed for good.

Cassian's story shows that this early intervention can work, fostering hope for other CHAOS cases.

"This work would best be carried out in the context of a clinical trial with rigorous data collected on the development impacts of the lung and tracheal growth," Farmer said. "But these are difficult to accomplish in rare diseases."

Vlastos said fetal surgeons, globally, should come together to discuss whether they have performed similar operations and to think of new strategies to improve the surgery. For instance, they could find smaller catheters that are more appropriate for a fetus or develop less invasive approaches to drain the lungs.

Cassian's surgery may sow the seeds for doctors to perform similar operations in the future, but it would never have happened if it weren't for the trust of his parents.

"They never stopped asking the very important question, 'What else could we try?'" Greves said. "I do believe, in the end, this made all the difference."

This article is for informational purposes only and is not meant to offer medical advice.

Imagine getting a knee replacement made of living materials rather than metal and plastic.

Researchers at Columbia University and the University of Missouri are working to make that vision a reality. Their 3D-printed knee implant, called NOVAKnee, is composed of a biodegradable scaffold packed with stem-cell-derived bone and cartilage. The idea is that, once inside the body, the scaffold will gradually disappear as it's replaced by new bone and cartilage that will integrate into the patient's skeleton.

Conventional knee implants last up to 20 years, and ideally, they're installed in later adulthood, when the patient is likely to need only one implant for the rest of their life. That leaves younger patients with few options; if they get an implant sooner, they'll likely need a revision surgery down the line, and if they wait, they'll spend years with pain and limited mobility.

NOVAKnee could be a better option for these patients. The implant has been tested in lab mice, in experiments where a tiny version was placed beneath the animals' skin to see how the body reacted. It will soon be tested in larger animals in experiments that replicate how a knee replacement works in humans; the type of animal being used for those tests has not been disclosed yet.

If all goes well, the developers hope to launch their first human trials as soon as 2028. The work is being supported by a federally funded project called Novel Innovations for Tissue Regeneration in Osteoarthritis (NITRO).

Live Science spoke with two of the developers — Clark Hung, a professor and vice chair of the Department of Biomedical Engineering at Columbia University's School of Engineering, and Nadeen Chahine, a professor of biomedical engineering in orthopedic surgery at the Columbia University Vagelos College of Physicians and Surgeons — about the new technology.

Nicoletta Lanese: What are the issues with conventional knee implants that NOVAKnee aims to address?

Clark Hung: Conventional knee replacements, metal and plastic implants, actually work really well. But they're limited to 15 to 20 years, basically until they fail, from a materials perspective. If you're not toward the last couple of decades of your life, there's a good chance that you're going to outlive your implant, which would require having another implant put in — that's called a revision surgery.

When it [the first implant] fails, the physician has to go in and try to pull that implant out without destroying the bone that's there. And they actually have to make a larger opening to put the new implant in.

Nadeen Chahine: When the patients are older, when they're having that revision, you're dealing with weaker bone, or higher bone mass loss, compared to that younger patient. So that comes with a higher risk of loosening [the implant becoming unstable within the knee joint] and higher risk of failure.

CH: So if you're a younger patient who's missing a lot of the anatomic surface of your cartilage, most surgeons will tell you to wait and take meds to relieve pain until you're older, to get the actual knee replacement.

The goal here is really to get people back to function and have no pain. One of the challenges, therefore, is to come up with a living version of a knee replacement, where it could possibly be your last knee replacement and something that will have a longer duration of success than current implants.

NL: Do you think NOVAKnee could be useful to older knee transplant patients, as well?

NC: It's not entirely fully clear, to be honest. The data has to play out to see what patient populations are going to benefit the most. I think we see that there is an opportunity to help younger adults who currently have no options — no treatments besides injections and stopgap measures to help them manage the pain and disability that they're going through.

NL: In terms of the surgery, should this knee replacement work just like a normal one?

CH: It's supposed to be pretty similar. … We are embracing, at least from a commercialization perspective, the orthopedic surgeon's role in this process in that we're coming up with a living version of something they're familiar with.

NL: Could you theoretically accomplish something similar without an implant, by introducing stem cells directly to the knee joint, for instance?

CH: Other projects in the NITRO portfolio are looking at injectables to regenerate bone and cartilage. As of now, there's nothing commercially available that can meet those demands. Most things on the market are there to relieve pain, whatever that mechanism is — from viscosupplementation, where you essentially inject Jell-O into the knee to try to cushion the joint, to corticosteroids. It's masking the inherent issue [of the joint being degraded]. The NITRO program as a whole is aimed at making the problem go away one way or the other.

[When it comes to injectables] I'm not really sure how these products will work if you have major damage to the articular surface [where the bones of the joint meet], where most of the cartilage is missing. In those situations, something like we're proposing might be more appropriate because you may or may not have the time [to regrow that tissue] if you're essentially bone-on-bone.

We did joke at the beginning of the program that, theoretically, if these injectables work, it would put us out of business. But in my mind, I think there are a lot of people who have implants already — conventional ones — and if those were to fail and need revision, our product would still have a role.

NL: How did you go about designing the implant's scaffold?

NC: The goal is that it's there to elicit a response that's controlled and well-defined ‪—‬ and then it will degrade over time, and that will result in components that are natural to the body that then get broken down through the normal mechanisms.

What we sought to do is to build on that by creating something that looks like a knee and functions like a knee but can't be a permanent material like metal and plastic.

NL: And where do the stem cells come in?

NC: We are developing two versions of the technology. One of them will be seeded with the patient's own cells. We would isolate stem cells from the patient and then use that to generate cartilage and bone cells, and that would be our "autologous" product [derived from the same individual]. Those cells then get put back on the scaffold, and then we would implant them.

On the other hand, there are some considerations where a patient might not be a good candidate for autologous therapy, or their regenerative potential is not quite what it needs to be. At that point maybe, we want to consider using allogeneic cell sources [cells from other people] and getting donor cells from a bank prepared using the same mechanisms.

We still need to understand a little more definitively who the ideal candidate is for autologous versus allogeneic, and how we decide on the clinical workflow of who should get one or the other. Right now we're still in this R&D phase.

NL: In a human patient, how long would the scaffold take to break down and leave the new cells on their own?

NC: That's a very hard thing for us to predict exactly. We've done studies both on the biodegradation, as well as studies on the matrix synthesis [the growth of bone and cartilage], and have some ideas of how those are happening. But to date, we've only studied them in small animal studies.

We have some idea of how much matrix is being synthesized and how much degradation is happening [once the implant is] in the body, but not necessarily in the knee. What we also don't yet know is how the presence of mechanical loading, the use of your knee implant, affects both how much it degrades and how much matrix is being synthesized.

That's what we're studying at this new phase of the project [in the large animal experiments]. These are really important questions that we want to be able to answer to modify our approach if needed, to address any potential shortcomings.

CH: In our large, preclinical animal studies, NITRO is mandating that we use an arthritis model. So we're basically going to create osteoarthritis in the animals and then do the living knee replacement. It's going to simulate better what clinically happens in people.

NL: Since it sounds like human trials might start fairly soon, are you preparing for those already?

CH: This program we're in is a five-year program: two years of R&D, basically benchtop; 18 months of large animal studies; and then 18 months of Phase I [safety] clinical trials. Trials would be 18 months or two years from now if everything went perfectly with our animal studies and the FDA greenlit it and said, "Hey, this is perfect data; we're going to give you the option to go into humans." So it's probably really ambitious, but the whole program is ambitious.

NC: We've gotten a lot of interest from people all over the country and abroad who want to learn about the trial or who are asking us, "Should I postpone my knee replacement so that I could join your trial?" We obviously can't answer any of those questions yet, but we really value the enthusiasm and the interest. We have a form that should be going up on our website so that those individuals that want to stay engaged can learn about the progress.

Honestly, while we've been buried in technical research and sweating those details to make sure we're doing the best science we can to bring forward this technology, it's very refreshing and very eye-opening to hear about the needs of regular people everywhere who are telling us how desperately they are in need of something like this. I'm getting calls and texts from my friends' parents, from people that live in my community, everywhere — "Please tell me, what can I do?"

NL: For the people who reach out, are there particular trends? Are they mostly younger patients waiting on a future knee implant, for instance?

NC: I think there's a lot of that. They're too young, and waiting makes sense. And maybe they're not as advanced, as in they're not full bone-on-bone but they're still in a lot of pain and discomfort. Some of them have had to give up certain activities or sports that they've enjoyed that now they can't do. It's a lot of that.

CH: I've seen a couple where people just don't want foreign objects in them. Theoretically, if this all works out — and let's say you have cells from yourself, it's autologous, if everything absorbs away like it's supposed to — then eventually, it becomes you, your own bone and cartilage.

So some people are like, "If I could have something that's living, that's going to be part of me and not something that's going to be sticking around as an object in me, I'd prefer that."

NL: Zooming out, do you think this new technology could be useful for other joint replacements?

NC: If it was up to us to decide what joint to try this first, we wouldn't have picked the knee. I understand where the decision came from because that's where there is the greatest need. However, from a mechanical perspective and from a joint function and range-of-motion standpoint, it's probably one of the hardest. We would have started in a different joint, just to kind of build up the proof of concept in something that's a little bit more forgiving.

Given that context, I think we have a desire and a vision to see this as a platform technology that could be developed for other large joints, or even some smaller joints, depending on the function and the need. Hopefully, in due course, that's something that we'll want to pursue.

NL: If you had your pick, what joint would you have started with?

NC: One of our collaborators tells us the thumb is a very important area that actually doesn't have very good technology currently, that is usable for [joint] replacement. Despite it looking like a very small joint, it actually undergoes a lot of high forces, but the range of motion is more limited. So that could be something that we could have worked on.

CH: And everybody likes to have their ability to grip things and "pincer action" [using the pointer finger and thumb to pick things up].

NC: And we're all going to get really bad OA [osteoarthritis] of our thumbs with all the texting we do. So it's been a problem, but it's only going to get worse with the aging population.

This article is for informational purposes only and is not meant to offer medical advice.

The patient: A 20-year-old man in China

The symptoms: The patient had gotten a red cross tattooed on his neck, just below his voice box. But three months later, the ink vanished.

The man developed lumps on both sides of his neck, which grew gradually. Indented scars appeared where the ink had once been, along with ulcers made of dead tissue that were filled with a pinkish mixture of serum and blood. These types of growths are known as "necrotic" ulcers.

The patient went to the hospital about five months after his tattoo appointment. He was prescribed antibiotics and topical corticosteroids, but his symptoms did not improve.

What happened next: When doctors physically examined the patient, they identified hard and swollen lymph nodes on both sides of his neck, just below his jaw. They also examined a large necrotic ulcer on the middle of the base of his neck, finding that the crusted mass had spread to the deeper layers of his skin.

MRI showed the lump on each side of the man's neck was approximately 1.6 by 1.2 inches (4 by 3 centimeters), while a central mass below the large necrotic ulcer was 1.9 by 1.4 inches (4.9 by 3.5 cm). An enhanced CT scan revealed blood clots in the two jugular veins closest to the midline of the neck.

The doctors then used fine needles to take biopsies of the necrotic ulcer, which revealed dead cells, immune cells and scar tissue. This did not point to what triggered the necrosis. But because the medical team was concerned by the scan results and the pace at which the man's condition was progressing, the patient was immediately sent to surgery, the doctors wrote in a report of the case.

The team removed the ulcer and masses and tied off the clotted jugular veins to prevent blood flow. The patient's neck was then reconstructed using tissue from his thigh.

The diagnosis: The team ran immunohistochemical tests on the biopsy samples, in which they used antibodies to check for specific antigens, or immune-response-triggering substances. The results were negative for both Epstein-Barr virus, the germ that causes mono, and tuberculosis, but a type of cell that forms benign tumors was detected.

"These findings collectively supported a diagnosis of necrotizing granulomatous lymphadenitis," the doctors wrote. "Granulomatous" refers to a condition in which clusters of immune cells form a wall around persistent infections or foreign materials.

Necrotizing granulomatous lymphadenitis is an immune response mounted against a bodily injury — in this case, the man's cross tattoo. The doctors also noted in their report that heavy metals, such as mercury and cadmium, and red organic dyes in tattoo pigments can sometimes trigger delayed immune responses. However, none of the vanished tattoo pigment was detected in the surgically removed lesions, so they couldn't examine its contents directly.

The treatment: Following surgery and a bout of short-term hormone therapy, the man made a full recovery, the doctors reported. (They did not specify the type of hormone treatment he was given or why it was necessary.)

What makes the case unique: Tattoos can come with potential health risks, such as allergic reactions and skin infections. In a study of 226 people who had reactions to tattoos, granulomatous reactions were relatively common, making up 48% of the inflammatory responses reported.

The doctors noted that this man's case is only the second known reported case of necrosis following a tattoo. In the other known case, the patient experienced necrobiosis lipoidica, a rare inflammatory skin condition in which the collagen in the skin degrades, and early granuloma annulare, characterized by a raised, ring-shaped rash.

The man's necrotic ulcer was also particularly aggressive, the doctors noted, and it was unusual in how deep into the skin it had spread.

The doctors suggested three potential causes for the man's severe necrosis. First, the chronic inflammation and otherwise-heightened immune response triggered by the tattoo could have raised his risk of blood clotting. Alternatively, the enlarged lymph nodes on the sides of his neck may have compressed the jugular veins and thus slowed blood flow. A final possible explanation is that the walls of his veins began to erode due to the chronic inflammation.

In all, "this report expands the spectrum of tattoo-associated pathology," the doctors wrote in the report. Given that this is the second known case, though, it's likely a very rare outcome.

For more intriguing medical cases, check out our Diagnostic Dilemma archives.

This article is for informational purposes only and is not meant to offer medical advice.

Dr. John Pandolfino jokes that he comes from a long line of electricians and plumbers — and that as a gastroenterologist, he's stayed in the family business.

That's because the esophagus, the organ that brings food from your mouth to your stomach, is basically a pipe with some electrical wiring, he said.

Pandolfino is the chief of gastroenterology and hepatology and director of the Northwestern Medicine Digestive Health Institute. He's begun using "digital twins" to model how individual patients with a swallowing disorder will respond to surgery called a myotomy, which is used to cut the esophagus. In the most futuristic conceptions of a digital twin, doctors would combine nearly identical anatomical replicas of an individual's body with biodata to recommend highly personalized medicine or procedures.

The digital twins Pandolfino's team has developed aren't quite that advanced: They use dimensionally accurate virtual models to re-create the pressure and motion of the esophagus. He and his colleagues have recently started a 400-person clinical trial that will investigate whether using these virtual clones to guide surgery will result in better outcomes for patients.

We spoke with Pandolfino about the future of digital twins, whether they could reduce animal testing, and how they could be used in organs beyond the esophagus, like the heart and bladder.

Tia Ghose: You're using a digital twin in a condition called achalasia. Can you tell me more about what this condition is?

John Pandolfino: The esophagus, you know, its main job is to push things down into your stomach once it enters the esophagus. And then when something refluxes up, the esophagus also has to push it down to protect you from aspirating and getting it into your lungs. What happens in achalasia is, the lower esophageal sphincter, which is kind of the barrier that separates the esophagus and the stomach, doesn't open up. It doesn't relax. Achalasia actually means failure to relax. When that muscle doesn't relax and open, the food just accumulates in your esophagus and you literally, almost, start drowning on your own saliva and food. So it could be a deadly disease.

What was interesting was that we noticed after treating patients, they were developing this diverticulum [a weakening and ballooning of the wall], and we didn't really understand why this was happening. So we asked the mathematical model, the virtual esophagus — we actually gave it a bunch of options. We changed a lot of the variables, like what type of surgery are they having? How long did they cut the muscle? Did they include something called an anti-reflux procedure, where you kind of take part of the stomach and wrap it around the esophagus so you wouldn't get reflux? Would it matter what kind of motility problem they had? There's different subtypes of achalasia. So would some subtypes be better than others? We went through this whole process. How deep would you cut the muscle? And we just ran simulations.

So it took a couple months of training this and letting it run through millions and millions of scenarios to show what would happen. And in the end, the model actually predicted what would be the best surgery, and it also predicted which patients would be at highest risk to develop the complication.

So with that information, we then submitted an NIH grant that focused on looking at two different types of surgery: the standard approach versus one that's modified by the virtual esophagus, so what the virtual esophagus picked. So we are going to test this standard approach, which works pretty well, versus this other approach. And we believe we've modeled the study so that they look equivalent, but we believe the new one will have less reflux and less diverticulum development.

TG: What you're describing seems like a far cry from what people are describing as a canonical digital twin, where you integrate all the key chemicals and signaling processing involved, all the mechanical forces and all the real-time data from wearables and medical imaging. How far away do you think we are from that type of digital twin?

JP: From a mechanical standpoint, I think it's pretty good already.

In terms of getting into the molecular structure and the actin [muscle filaments] and how muscles contract and the calcium influxes, I think that we're really far away. We've just learned how the proteins fold; developing a mathematical model of the cell is going to take a pretty long time.

But I think, mechanically, we can do this, and the great thing is that this approach canbe adopted across all organ systems ‪—‬ the bladder, the aorta, the left ventricle. These processes where you rely completely on the mechanics of transport — now, we can take this and apply it across those [systems].

TG: So what you envision right now being pretty close is mainly for pump-and-tube-type systems and largely for surgeries. Do you see it as having prognostic or diagnostic value?

JP: It certainly will have prognostic value because you get to the point where you can pick up scenarios where medications will have no effect anymore, right? So, if someone gets to the point where they have deformation of the wall, that wall is gone. No medicine you give them is going to make them better.

TG: People have floated the idea that a digital twin could be used to supplant some animal research and clinical trial data.

JP: Yeah.

TG: Do you actually think that's realistic?

JP: If you're looking at surgeries, you wouldn't need to do this on animals. You would do this on a simulation, like we have, to see what the effects are, and then you could actually go from that to various changes in humans. That's exactly what happened here: Our virtual esophagus proved what we thought would probably be the right way to do this. So it proved our hypothesis mathematically, and now we're embarking on a human trial.

TG: But most animal research, I would guess, is focused on testing new compounds that could have therapeutic potential, right? So, do you think it has much potential there?

JP: Those studies where they give a mouse like 50 times the dose that a human would get to see, is it going to kill it? I don't think [digital twin technology will] affect that. What it will do is, it'll take us away from using animals for surgery.

In addition, I do think that this is going to lead us to an area where we will be able to create much better models for simulation. So we'll understand a lot more regarding the material properties of the organs, how they respond to stress and strain, and develop simulations that run not just in the virtual world but actually have tactile twins, right? So something that actually is made from a material that simulates the esophagus or simulates an organ almost perfectly so that when you're cutting it, it's the same feel.

TG: You could train on it and you could pour goop down it and see how it expands or something?

JP: Exactly. But you know, there's just a lot you can learn from understanding one part of the human anatomy and function, because the body doesn't come up with totally different ways to do things. It repeats it, and it just may make it bigger or smaller, use a slightly different length. [Organs like the bladder and heart] all work pretty similarly. They have a tube that has some contraction. There are sphincters that open up and close. If you even look at the esophagastric junction, the valve that's at the anti-reflux barrier, it's very similar to the ano-rectal junction where you have a bowel movement. And, in fact, if you look at the physiology of how you have a bowel movement and how you swallow and protect yourself from having reflux, they're literally just reversed.

TG: Nature just copies itself.

JP: Yeah.

TG: So you think this has a lot more applicability across the body?

JP: Yeah, even in the esophagus. I mean reflux heartburn affects like a fifth of the country. And really, reflux is not an issue of too much acid. Most people who have reflux have normal acid.

It's more of an anatomy and a physiology issue. So, you know, our approach will allow us to hopefully modify a lot of the surgeries that are being done for reflux and even maybe help create less-invasive approaches that work. So, just in the GI [gastrointestinal tract] in general, in the esophagus, it's going to have a lot more application. And then even in people who may have bladder issues, an overactive bladder or maybe a hypoactive bladder, how do you assess that in relationship to flow and emptying of the bladder? [It's] similar in aortic aneurysms. Aortic aneurysm is basically a diverticulum. It's just a pressure-related change in the anatomy where it basically balloons out. And when it balloons out, because it balloons, it loses its function, and then the blood's not pumping right.

This article is for informational purposes only and is not meant to offer medical advice.

Around 2,500 years ago in Siberia, a young woman experienced a serious head injury, underwent surgery to reconstruct her jaw, and received a primitive prosthetic during the procedure, CT scans of the woman's mummified remains reveal.

"It is possible that we have discovered evidence of such a surgical procedure for the first time," Dr. Andrey Letyagin, a radiologist at the Siberian Branch of the Russian Academy of Sciences, said in a translated statement, since "we had not previously encountered [it] in the scientific literature."

Using CT scans to nondestructively study a permafrost-preserved mummy allowed the researchers to not only "diagnose the injury but also reconstruct the results of a complex surgical intervention performed in ancient times," Vladimir Kanygin, head of the Laboratory of Nuclear and Innovative Medicine at Novosibirsk State University in Russia, said in the statement, "transforming a single find into detailed evidence of the Pazyryk culture's high level of medical knowledge."

The Pazyryk culture, a nomadic Iron Age group related to the Scythians, flourished on the Ukok Plateau in the Altai Republic in southern Siberia. Pazyryk graves are well known for their outstanding preservation of organic remains in the permafrost, including the "Princess of Ukok," whose fantastical animal tattoos were perfectly preserved for more than 2,000 years.

In 1994, archaeologists with the Russian Academy of Sciences excavated a small cemetery consisting of five low mounds on the Ukok Plateau. One mound held the undisturbed burial of a woman who was around 25 to 30 years old when she died. She was lying on a wooden cot and was wearing a wig. But because her burial lacked significant artifacts and only a part of her head was mummified, her burial was not fully investigated at the time.

"This mummified patch of skin on the buried woman's skull made anthropological research impossible, but we wanted to learn as much as possible about her," Natalia Polosmak, an archaeologist at the Siberian Branch of the Russian Academy of Sciences, said in the statement. "The opportunity to study it on a CT scanner was a fortunate opportunity, which I took advantage of."

The CT scans of the woman's skull revealed a head injury had destroyed her right temporomandibular joint (TMJ). The injury would have prevented the woman from speaking and eating normally. Given that the Pazyryk people routinely rode horses, the woman may have sustained the injury as she fell off while galloping, according to the statement.

Discovery of a "primitive prosthetic" device

Although the woman's injury was not unusual, the unique treatment for the damage to her bones and ligaments surprised the researchers. They found thin canals drilled into the two bones that made up the woman's right TMJ, as well as horsehair or animal tendon in the canals holding the joint together.

"This primitive prosthetic held the articular surfaces together and allowed the patient to move her jaw," Letyagin said. "The joint functioned, but she still couldn't chew food on the injured side, likely due to severe pain."

Several aspects of the woman's skull revealed that she lived for several months — or even years — following the surgery. New bone tissue had grown around the canals in her right TMJ, and the teeth in the left side of her jaw were worn and chipped, suggesting she compensated for the right-sided injury by chewing exclusively on her left.

The Pazyryk people knew how to perform basic skull surgery in the days before anesthesia; evidence of trepanation in the form of holes in the skull has been found in several mummies. They also had a deep understanding of human anatomy and dissection, according to the statement, which was necessary for their tradition of mummifying bodies. But the woman's TMJ surgery is a rare example of their skills.

Although this woman was buried in a simple manner, without significant artifacts, the successful operation on her jaw "indicates that her life was valued," Polosmak said. "This new study provides further important confirmation that the Pazyryk people were able to perform complex surgical procedures to save the lives of their fellow tribesmen."

In a New York operating room one day in October 2025, doctors made medical history by transplanting a genetically modified pig kidney into a living patient as part of a clinical trial. The kidney had been engineered to mimic human tissue and was grown in a pig, as an alternative to waiting around for a human organ donor who might never come. For decades, this idea lived at the edge of science fiction. Now it's on the table, literally.

The patient is one of six taking part in the first clinical trial of pig-to-human kidney transplants. The goal: to see whether gene-edited pig kidneys can safely replace failing human ones.

A decade ago, scientists were chasing a different solution. Instead of editing the genes of pigs to make their organs human-friendly, they tried to grow human organs — made entirely of human cells — inside pigs. But in 2015 the National Institutes of Health paused funding for that work to consider its ethical risks. The pause remains today.

As a bioethicist and philosopher who has spent years studying the ethics of using organs grown in animals — including serving on an NIH-funded national working group examining oversight for research on human-animal chimeras — I was perplexed by the decision. The ban assumed the danger was making pigs too human. Yet regulators now seem comfortable making humans a little more pig.

Why is it considered ethical to put pig organs in humans but not to grow human organs in pigs?

Urgent need drives xenotransplantation

It's easy to overlook the desperation driving these experiments. More than 100,000 Americans are waiting for organ transplants. Demand overwhelms supply, and thousands die each year before one becomes available.

For decades, scientists have looked across species for help — from baboon hearts in the 1960s to genetically altered pigs today. The challenge has always been the immune system. The body treats cells it does not recognize as part of itself as invaders. As a result, it destroys them.

A recent case underscores this fragility. A man in New Hampshire received a gene-edited pig kidney in January 2025. Nine months later, it had to be removed because its function was declining. While this partial success gave scientists hope, it was also a reminder that rejection remains a central problem for transplanting organs across species, also known as xenotransplantation.

Researchers are attempting to work around transplant rejection by creating an organ the human body might tolerate, inserting a few human genes and deleting some pig ones. Still, recipients of these gene-edited pig organs need powerful drugs to suppress the immune system both during and long after the transplant procedure, and even this may not prevent rejection. Even human-to-human transplants require lifelong immunosuppressants.

That's why another approach — growing organs from a patient's own cells — looked promising. This involved disabling the genes that let pig embryos form a kidney and injecting human stem cells into the embryo to fill the gap where a kidney would be. As a result, the pig embryo would grow a kidney genetically matched to a future patient, theoretically eliminating the risk of rejection.

Although simple in concept, the execution is technically complex because human and pig cells develop at different speeds. Even so, five years prior to the NIH ban, researchers had already done something similar by growing a mouse pancreas inside a rat.

Cross-species organ growth was not a fantasy — it was a working proof of concept.

Ethics of creating organs in other species

The worries motivating the NIH ban in 2015 on inserting human stem cells into animal embryos did not come from concerns about scientific failure but rather from moral confusion.

Policymakers feared that human cells might spread through the animal's body — even into its brain — and in so doing blur the line between human and animal. The NIH warned of possible "alterations of the animal's cognitive state." The Animal Legal Defense Fund, an animal advocacy organization, argued that if such chimeras gained humanlike awareness, they should be treated as human research subjects.

The worry centers on the possibility that an animal's moral status — that is, the degree to which an entity's interests matter morally and the level of protection it is owed – might change. Higher moral status requires better treatment because it comes with vulnerability to greater forms of harm.

Think of the harm caused by poking an animal that's sentient compared to the harm caused by poking an animal that's self-conscious. A sentient animal — that is, one capable of experiencing sensations such as pain or pleasure — would sense the pain and try to avoid it. In contrast, an animal that's self-conscious — that is, one capable of reflecting on having those experiences — would not only sense the pain but grasp that it is itself the subject of that pain. The latter kind of harm is deeper, involving not just sensation but awareness.

Thus, the NIH's concern is that if human cells migrate into an animal's brain, they might introduce new forms of experience and suffering, thereby elevating its moral status.

The flawed logic of the NIH ban

However, the reasoning behind the NIH's ban is faulty. If certain cognitive capacities, such as self-consciousness, conferred higher moral status, then it follows that regulators would be equally concerned about inserting dolphin or primate cells into pigs as they are about inserting human cells. They are not.

In practice, the moral circle of beings whose interests matter is drawn not around self-consciousness but around species membership. Regulators protect all humans from harmful research because they are human, not because of their specific cognitive capacities such as the ability to feel pain, use language or engage in abstract reasoning. In fact, many people lack such capacities. Moral concern flows from that relationship, not from having a particular form of awareness. No research goal can justify violating the most basic interests of human beings.

If a pig embryo infused with human cells truly became something close enough to count as a member of the human species, then current research regulations would dictate it's owed human-level regard. But the mere presence of human cells doesn't make pigs humans.

The pigs engineered for kidney transplants already carry human genes, but they aren't called half-human beings. When a person donates a kidney, the recipient doesn't become part of the donor's family. Yet current research policies treat a pig with a human kidney as if it might.

There may be good reasons to object to using animals as living organ factories, including welfare concerns. But the rationale behind the NIH ban that human cells could make pigs too human rests on a misunderstanding of what gives beings — and human beings in particular — moral standing.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

A woman in California was scheduled to have a large cyst removed and tested positive on a routine pregnancy test just prior to the procedure. She would soon learn that she actually had a full-term baby tucked away in her abdomen, hidden behind the cyst.

Suze Lopez, a 41-year-old emergency room nurse from Bakersfield, underwent a procedure to have both the cyst removed and her baby delivered at the same time. The effort involved about 30 medical professionals at Cedars-Sinai Medical Center in Los Angeles.

Lopez began hemorrhaging after the baby was delivered but was stabilized by the medical team, who used 11 units of blood to do so, according to a statement from Cedars-Sinai. (For context, a typical blood donation is about one pint of blood, which is one unit.)

The baby, who weighed 8 pounds (3.6 kilograms) at birth and had a full head of hair, was quickly transferred to the neonatal intensive care unit (NICU) after birth. All things considered, he was remarkably healthy, his physicians said.

"I was amazed by this little guy," Dr. Sara Dayanim, a neonatologist with Cedars-Sinai Guerin Children's, said in a video accompanying the announcement. "He's defied all odds," she said.

How the pregnancy went undetected

The baby, named Ryu, was discovered because Lopez was scheduled to have a 22-pound (9.9 kg) ovarian cyst removed. The cyst was noncancerous, but it had been growing for years by the time Lopez was scheduled to undergo the surgery.

Lopez was used to experiencing irregular periods and abdominal discomfort, so she didn't expect to get a positive result on the pregnancy test prior to the surgery. She surprised her husband Andrew with news of the pregnancy while at a Dodgers baseball game in Los Angeles; the pair snapped a selfie together while holding up a Dodgers-branded onesie.

However, later at the game, Lopez started to have intense abdominal pain, and they immediately went to Cedars-Sinai.

Lopez arrived at the hospital with very high blood pressure, and as medical staff set about treating it, they also ran blood work and body scans, including an MRI and ultrasound. That's when they discovered that Lopez was carrying a rare abdominal ectopic pregnancy. The baby was situated near the liver, with his back half resting on top of the uterus.

"It was the baby growing in her abdomen behind the mass that was pushing everything out," Dr. John Ozimek, medical director of Labor and Delivery and the Maternal-Fetal Care Unit at Cedars-Sinai, said in the video. "So that's the reason she didn't know she was pregnant."

He added that "a pregnancy this far outside of the uterus that is living is pretty much unprecedented."

Ectopic pregnancies occur outside the uterus and account for roughly 2% of all pregnancies. All forms of ectopic pregnancy, in any location in the body, are life-threatening, as they can rupture organs and cause catastrophic bleeding and, potentially, shock due to blood loss. Ectopic pregnancies cannot be transferred into the uterus, and as such, medical guidance is to treat the condition by ending the pregnancy, either with medication or surgery.

The vast majority of ectopic pregnancies — about 95% — occur in a fallopian tube, a tube that shuttles eggs from an ovary to the uterus. Abdominal ectopic pregnancies, by comparison, occur in only about 1% of ectopic pregnancy cases.

If an ectopic pregnancy escapes notice — as in this case — it's very improbable that the fetus would develop normally outside the uterus. Thus, fetal death is likely.

That said, the medical literature includes a handful of unusual cases in which abdominal ectopic pregnancies were discovered very late in gestation and ultimately resulted in the birth of healthy babies.

In Lopez's case, "we had to figure out how to deliver the baby with a placenta and its blood vessels attached in the abdomen, remove the very large ovarian mass and do everything we could to save mom and this child," Dr. Michael Manuel, a gynecological oncologist at Providence Cedars-Sinai Tarzana Medical Center, said in the statement. And in the end, they were successful.

Lopez, who has a teenage daughter, had been hoping for a second pregnancy for years.

"I could not believe that after 17 years of praying, and trying, for a second child, that I was actually pregnant," she said in the statement. "I appreciate every little thing. Everything. Every day is a gift and I'm never going to waste it."

This article is for informational purposes only and is not meant to offer medical advice.

Archaeologists in Poland have discovered a rare iron tool that the Celts used to perform cranial surgery 2,300 years ago.

The hand-held artifact was found at Łysa Góra, a Celtic site in the Mazovia region of central-eastern Poland.

"The technique and precision of the iron object's manufacture indicate Celtic metallurgy," Bartłomiej Kaczyński, an archaeologist at the State Archaeological Museum in Warsaw, told Live Science in an email, and it was likely used to trepan a human skull.

From the Greek word meaning "to bore," trepanation is a form of cranial surgery that was practiced in many cultures around the world — including in what are now Spain, Israel and Bolivia — for at least 5,000 years, until the beginning of the 19th century.

There are a few trepanation methods, but most Celts appear to have used the "traditional scraping technique of trepanation," and only a minority of Celtic settlements practiced "drill trepanations," according to a 2007 study in the journal Neurosurgical Focus.

"The Celts practiced trepanation, as indicated by individual tools discovered in graves," Kaczyński said. "It seems that these operations had not only a magical but also a medical purpose."

But so far, they have found no skeletons of people who underwent the procedure at Łysa Góra.

The presence of Celts — fierce warriors who were native to the European mainland and sacked Rome — was somewhat surprising, the team said, since Łysa Góra is the most northeastern Celtic site ever found in Europe.

Kaczyński and his team have been conducting new archaeological digs at Łysa Góra, which was first excavated in the 1970s, for two years.

In 2024, the archaeologists found hundreds of artifacts, including a rare Celtic helmet made of thin bronze sheet metal. And in the 2025 excavation, the team found Celtic brooches, a spearhead and an iron ax, as well as numerous metal objects related to horseback riding.

The trepanation tool, discovered this spring in the same part of the site as the helmet, is even rarer than the helmet, according to Kaczyński, because only a few of these surgical tools have been found at Celtic sites. This particular implement, which features a blade that transitions to a spike and was probably originally fastened to a wooden handle, is a type of ancient scalpel.

Kaczyński told Science in Poland that the presence of an iron trepanation scalpel means that the Celts who settled in the region likely included someone with specialized medical or ritual knowledge, as well as a blacksmith who could create the tools found at Łysa Góra.

The excavations at Łysa Góra have thus far revealed that it was a fortified settlement even before the Celts arrived in the fourth century. But once the Celts arrived, "traces of bronze and iron metallurgy, unique imports, fragmented bronze and amber objects all indicate that the settlement was a key center of trade," Kaczyński said.

Amber was a prized material in the Mediterranean world at this time, Kaczyński told Live Science in 2024, and the Celts may have fortified Łysa Góra to protect their place on the "amber trail."

Celtic quiz: Test your knowledge about these fierce tribes once described by Julius Caesar

This week's science news has been out of this world, with NASA's announcement that speckled rocks found on Mars may be the clearest sign yet that life once existed on the Red Planet.

The rocks all contain flecks of leopard-like spots that, on Earth at least, are telltale signs of chemical reactions that microbes use for energy. This, alongside the presence of organic compounds and evidence of water once flowing through the rocks, has gotten scientists seriously excited.

But keep the Champagne corked, because it's still possible that the marks may have been left by inorganic processes, meaning we'll have to wait for the politically endangered Mars Sample Return mission before we know for sure.

This week also thankfully brought us more conclusive news from the Laser Interferometer Gravitational-wave Observatory (LIGO). By detecting faint ripples in space-time released by the merger of two distant black holes, the detector finally confirmed a decades-old theory by Stephen Hawking that the cosmic monsters link general relativity to quantum mechanics.

Tying these two threads together into a theory of everything could be achieved with just one trip to a black hole. But making that trip would require some serious cellular engineering — if news of human stem cells experiencing accelerated aging in space is anything to go by. In the meantime, our planet has a close flyby by the asteroid Apophis and some strange-looking solar eruptions to get through.

LA's 'halo' barrel mystery begins to unravel

Scientists are finally learning what's inside mysterious 'halo' barrels submerged off Los Angeles

They appeared under the lights of deep-sea survey robots working off the coast of Los Angeles in 2020 — a graveyard of 27,000 barrels encircled by haloes of whitish, toxic sediment many at the time believed to be the banned pesticide DDT. Yet the exact quantity of the barrels, who put them there, and what they may contain remain unknown to this day.

However, a new study has shed some light into the murky situation. Analyzing samples collected from five of the barrels, researchers found that they didn't contain DDT after all, but caustic alkaline waste capable of killing most of the marine life in the vicinity. They also discovered the chemical reactions that form the haloes themselves, which they will use to identify the overall extent of the toxic spill.

Discover more planet Earth news

—'New' island emerges from melting ice in Alaska

—'Serious adverse and unintended consequences': Polar geoengineering isn't the answer to climate change

—Action on climate change faces new threat: The doomers who think it's too late to act

Life's Little Mysteries

Do humans and chimps really share nearly 99% of their DNA?

Humans and chimpanzees share nearly 99% of their genetic material: It's a frequently repeated truism about us and one of our closest-living relatives, but is it even true? It turns out not really, and even the comparison itself obscures a deeper truth about how DNA makes humans and chimps in the first place.

—If you enjoyed this, sign up for our Life's Little Mysteries newsletter

Visible time crystals created

Scientists create first-ever visible time crystals using light — and they could one day appear on $100 bills

Only theorized in 2012, time crystals have been captivating us since they were first created in 2016. Since those early years, scientists have replicated the fascinating phenomenon in a variety of systems, but none of them can be seen directly.

That's now changed, with the announcement that scientists have made visible time crystals out of the liquid crystals typically found inside LCD screens. These aren't just an intriguing demonstration of the bizarre quantum workings of time crystals, they could have practical applications too — possibly appearing on future high-denomination bills as anti-counterfeiting designs.

Discover more physics and mathematics news

—Scientists watch a single electron move during a chemical reaction for first time ever

—Meet the 'neglectons': Previously overlooked particles that could revolutionize quantum computing

—Lightning on Earth is sparked by a powerful chain reaction from outer space, simulations show

Also in science news this week

—New reconstructions show piercing eyes of men who lived 2,500 years ago in mysterious Indian civilization

—'Our hearts stopped': Scientists find baby pterosaurs died in violent Jurassic storm 150 million years ago

—Microsoft's new light-based computer is inspired by 80-year-old technology — it could make AI 100 times more efficient

—Diagnostic dilemma: A woman kept tasting bleach — and doctors found a hidden cause in her blood

Science Long Read

Camera trap in Chile detects strange lights blazing through the wilderness. Researchers are scrambling to explain them.

Just past midnight, in the silence and dark of Chile's far South Patagonia region, a camera trap picked up something inexplicable: Across three photos, intense lights danced downward in front of the lens.

Could they have been a camera artifact, ball lightning, or even UFOs? Live Science reported on the hunt for answers.

Something for the weekend

If you're looking for something to do over the weekend, here are some of the best polls, skywatching guides and crosswords published this week.

—'We have basically destroyed what capacity we had to respond to a pandemic,' says leading epidemiologist Michael Osterholm [Interview]

—Live Science crossword puzzle #9: A 'royal' snake that wears a hood — 14 across [Crossword]

— Have you gotten this year's COVID vaccine? [Poll]

Science in pictures

Interstellar comet 3I/ATLAS could be turning bright green, surprising new photos reveal

New photos of the comet 3I/ATLAS captured during the recent "blood moon" total eclipse appeared to show a surprising development — the comet, an interloper from beyond our solar system, may be turning green.

The most common explanation for this strange change (and no, it's not little green men) is the presence of diatomic carbon in the comet's coma, its fuzzy, temporary atmosphere. Yet with no diatomic carbon yet to be detected by spectroscopic observations, the jury is still out. Astronomers will need to take follow-up photos to confirm the effect and investigate its cause.

Follow Live Science on social media

Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, Bluesky and LinkedIn.

The watery part of the world dominated our science news coverage this week, beginning with the alarming prediction that a key Atlantic current, the Atlantic Meridional Overturning Circulation (AMOC), which includes the Gulf Stream, could begin its irreversible collapse in decades.

That's according to a new landmark study, which combined the predictions of 25 climate models to arrive at an "optimistic" prediction (under a moderate emissions scenario) that the current will begin to shut down due to climate change sometime in the 2060s. Given the current's vital role in regulating global climates, scientists have described the study as a "serious climate wake-up call."

Elsewhere, the signs of our warming world can be seen in the invasion of Antarctic icebergs around the South Atlantic Ocean's South Georgia Island. There, the former record-holder for the largest iceberg in the world, A23a, is undergoing a dramatic breakup. Meanwhile, deep beneath the Pacific Ocean, a team of scientists has discovered a giant hydrothermal system that could hold clues to the origins of life on Earth.

Mouse brain scans rewrite the textbook

Map of 600,000 brain cells rewrites the textbook on how the brain makes decisions

It's not often that a single piece of research comes along with the potential to rewrite everything that came before. Yet a massive collaboration of neuroscientists may have done just that with two new studies that mapped more than 600,000 individual mouse brain cells — or 95% of the rodents' brains.

The scientists hope the mammoth effort will help them study what parts of the mammalian brain are responsible for making decisions. In the past, scientists assumed that brain activity moves in a linear path, from visual recognition of a stimulus to regions responsible for abstract thinking, mixed with sprinklings from the memory regions to draw from experience.

But the new research found that significantly more of the mice's brains participated in this process, with decisions beginning to coalesce far earlier than expected. So far, the findings are only correlational, meaning the scientists still don't know whether all the regions are contributing, but they plan to attack this question as the next step of their work.

Discover more health news

— Diagnostic dilemma: Woman's severe knee pain reveals 'golden threads' in her joints

— Scraps of ancient viruses make up 40% of our genome. They could trigger brain degeneration.

— We finally have an idea of how the lifetime supply of eggs develops in primates

Life's Little Mysteries

Which animal has the best hearing?

Think of the animal with the world's sharpest ears and your mind might flutter onto bats. Take it a step further and one of their prey — the greater wax moth — could also be a contender, as the moths' ears are adapted to anticipate the ultrasonic chirps of their swooping hunters.

But just like any sense honed by natural selection, what qualifies as the best hearing is in the ear of the listener. Here are our major contenders for the animal world's best hearers.

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Chatbot suicide prevention doubts

'Extremely alarming': ChatGPT and Gemini respond to high-risk questions about suicide — including details around methods

A new study has raised doubts about the suicide prevention safeguards of three popular artificial intelligence chatbots (OpenAI's ChatGPT, Google's Gemini and Anthropic's Claude) finding that they were inconsistent in their replies to an extent that it could lead to serious harm.

The news came on the same day that the parents of 16-year-old Adam Raine filed a lawsuit against OpenAI, claiming that the company's chatbot had coached the California boy into taking his life earlier this year.

The new study found that ChatGPT offered direct answers to high-risk questions 78% of the time — some of which Live Science independently found the chatbot replied directly to.

All of this raises pressing questions about how a growing number of people, many of them younger, increasingly rely on these bots for advice on their mental health and personal lives.

Discover more technology news

— There are 32 different ways AI can go rogue, scientists say — from hallucinating answers to a complete misalignment with humanity

— AI can't solve these puzzles that take humans only seconds

— Scientists taught an AI-powered 'robot dog' how to play badminton against humans — and it's actually really good

Also in science news this week

— 1.8 million-year-old human jawbone discovered in Republic of Georgia — and it may be earliest evidence yet of Homo erectus

— Dozens of mysterious blobs discovered inside Mars may be the remnants of 'failed planets'

— How the racist study of skulls gripped Victorian Britain's scientists

— Newly discovered bus-size asteroid will zoom close past Earth today — and will not return for exactly 100 years

Science Spotlight

'We've never been able to do this before': How the James Webb telescope is leading us toward alien life

A $10 billion floating telescope, training its state-of-the-art lens at distant worlds to search for alien life: Humanity's search for aliens has come a long way since early suggestions that we simply light some big fires and wait for the spaceships to arrive, but can the James Webb Space Telescope really find what we're looking for?

In this week's science spotlight, we dig into the telescope's search for signs of habitable worlds beyond our solar system, including the scientific debate engulfing the 120 light-year distant K2-18b. The one thing scientists can agree on is that the planet likely smells of sweet cabbage, but whether its pungent gases are the byproduct of biological processes or not remains highly contested.

Something for the weekend

If you're looking for something to do over the weekend, here are some of the best polls, skywatching guides and crosswords published this week.

— Live Science crossword puzzle #8: Lowest possible temperature in the universe — 3 down [Crossword]

— Do you think we should stop the progress of AI before it becomes a threat to our species? [Poll]

— Who will see the 'blood moon' total lunar eclipse this weekend? [Skywatching]

Science in pictures

The world's first view of Earth from the moon, taken 59 years ago — Space photo of the week

This grainy, black-and-white image snapped by NASA's Lunar Orbiter 1 is the first ever photo of our planet snapped from the moon. Rising above the lunar horizon with the South Pole cloaked in shadow, the photo is hardly the most impressive one humanity has taken of our world from the moon's surface. But it was a landmark first and happened entirely by accident, according to NASA.

Follow Live Science on social media

Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, Bluesky and LinkedIn.

Researchers have modified a standard glue gun to 3D print a bone-like material directly onto fractures, paving the way for its use in operating rooms.

The device, which has so far been tested in rabbits, would be particularly useful for fixing irregularly shaped fractures during surgery, the researchers say.

"To my knowledge, there are virtually no previous examples of applying the technology directly as a bone substitute," study co-author Jung Seung Lee, a biomedical engineer at Sungkyunkwan University in South Korea, told Live Science in an email. "This makes the approach quite unique and sets it apart from conventional methods."

Typically, large fractures or other defects in bones require bone grafting and the use of a metal fastener, such as a pin or plate, to support the broken bone as it heals. But because the shape of these implants is not specific to a given patient's fracture, this can result in poor alignment and compromised stability of the bone.

Previous studies have shown that 3D printing bespoke bone grafts for individual patients can be done, but these required considerable time and effort to make, preventing them from being used on the fly during surgery.

Now, in a study published Friday (Sept. 5) in the journal Device, Lee and colleagues detailed their new method of 3D printing a bone substitute directly onto a fracture using a glue gun. In the research, they successfully tested the technology on rabbits with leg fractures.

Related: Injectable goo could fix joints without surgery, early study suggests

Basic 3D printing commonly uses a flexible, plastic thread, which is heated and then formed into the desired shape. But Lee and colleagues created a filament composed of two materials: polycaprolactone (PCL), which has been used in previous studies to create biodegradable bone scaffolds, and hydroxyapatite (HA), a mineral form of calcium important for bone structure. They also incorporated two antibiotics into the filament to help prevent infection; these drugs diffuse slowly out of the filament over several weeks.

Using a glue gun modified to extrude the calcium-based filament at a low temperature, the researchers created small shapes that cooled to body temperature within 40 seconds. They were then able to print 3D bone grafts directly onto fractures and defects during surgeries on the lab rabbits.

"This highlights a significant advantage in terms of reducing operative time and improving procedural efficiency under real surgical conditions," Lee said in a statement.

The researchers tested their 3D-printed bone grafts on New Zealand white rabbits (Oryctolagus cuniculus). They braced the fractures with metal plates and screws, and then filled the rabbits' bone defects with either their special bone-like filament or with traditional bone cement and followed the rabbits' progress over 12 weeks.

The rabbits with the new fracture treatment had better outcomes, including better bone tissue formation and denser bone growth over the three months, compared to the rabbits given traditional treatment. By the end of the study period, the experimental bone material had degraded by about 10%, they noted.

"We have confirmed the therapeutic potential of this technology using a rabbit model," Lee told Live Science, noting that further studies in larger animal models are needed before the technology can be used on humans. Nonetheless, Lee said, "we believe this approach has the potential to be used more widely in future trauma surgery."

This week's science news has been filled with medical breakthroughs, including the first-ever pig-to-human lung transplant into a brain-dead person.

The experiment, which took place in Guangzhou, China, kept the lungs alive and working for nine days, despite showing signs of rejection early on in the procedure. The researchers behind the study say that their work "paves the way for further innovations in the field," although questions remain about how successful such a procedure could be for a living patient removed from a life support machine.

Elsewhere, another study has found a potential route to laser-free vision treatment by zapping the eye's surface into a new shape using an electrical current. And researchers also found a link between gum disease and cardiovascular disease, with treatment reducing the narrowing of the carotid artery in otherwise healthy individuals.

Starship nails test flight

10th time lucky! SpaceX's Starship nails successful test flight after string of explosive setbacks

If at first your gigantic rocket explodes… explode it again and again until you succeed. That's been SpaceX's "fail fast, learn fast" ethos since it began development of its Falcon 9 rocket 20 years ago, and it finally paid off for its largest rocket, Starship, as it nailed a successful test flight this week.

The 10th test flight marks a comeback for the company after a string of explosive failures, some of which littered the Caribbean with debris. It came just in time for the company, and for NASA too — the rocket, the largest ever built, is key to ambitions to transport crewmembers, spacecraft, satellites and cargo into orbit around Earth, with a moon mission planned as early as 2027.

Discover more space news

— James Webb telescope images reveal there's something strange with interstellar comet 3I/ATLAS

— 'Potentially hazardous' asteroid Bennu contains dust older than the solar system itself — and traces of interstellar space

— NASA reveals the dwarf planet Ceres had a hidden 'energy source' that may have sparked alien life

Life's Little Mysteries

What is the world's slowest animal?

Cheetahs, marlins, peregrine falcons — fast animals get all the fame. But what about the slowest animals? And how do they survive in the wild while moving, literally, at a snail's pace? Here's our investigation into how Earth's most unhurried animals live life in the slow lane.

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Strange science

Scientists cram an entire computer into a single fiber of clothing — and you can even put it through your washing machine

Scientists have created a flexible, machine-washable fiber that can perform computing tasks. In theory, that means they could one day weave them together to form a "fiber computing network" made up of smart textiles.

These fibers have historically had limited computing ability, and scientists weren't able to embed multiple types of electronic components into them.

The new material weaves eight devices into a single fiber strand, including a photodetector, a temperature sensor, an accelerometer and a photoplethysmogram (PPG) sensor, which measures changes in light absorption by the skin. The material is also elastic, which makes it practical for clothing applications, the researchers say.

Also in science news this week

— Keratin extracted from sheep's wool repairs teeth in breakthrough

— 'This technology is possible today': Nuclear waste could be future power source and increase access to a rare fuel

— New brain implant can decode a person's 'inner monologue'

— Mystery quake that rocked Northern California in 1954 came from 'eerily quiet' Cascadia Subduction Zone

Beyond the headlines

'Aging clocks' tell you how much 'older' you are than your chronological age. How do they work?

There's the number of candles you blow out on your birthday cake, and then there's your "biological age," a measure of how much your biological systems have broken down over time. In other words, how well do your cells, organs and body systems work compared to a typical, healthy 40-year-old?

A number of scientists have touted their ability to measure this biological age with "aging clocks." These clocks often work by using AI to glean patterns from hundreds of biomarkers, or indirect measures of health, taken from large groups of people. They then compare a person's biomarkers against this aggregate group to pin down the biological age.

But can they really predict disease, and are the results reliable for commercial use?

Something for the weekend

If you're looking for something to do over the weekend, here are some of the best polls, book interviews and crosswords published this week.

—Live Science crossword puzzle #7: NASA mission that redirected an asteroid — 8 across [Crossword]

— Do you trust AI? [Poll]

— 'I would never let a robot incubate my child': Poll on 'pregnancy robots' divides Live Science readers [Poll results]

Science in pictures

Heartbreaking image shows a sloth clinging to a barbed wire fence because it was the closest thing resembling a tree

A sneak peek of the shortlisted 2025 Wildlife Photographer of the Year competition entries was released this week, featuring a heartbreaking shot of a sloth clinging to a wooden post, a lioness staring down a cobra, an ethereal jellyfish swarm, and clouds reflected in salt ponds in San Francisco Bay.

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Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, Bluesky and LinkedIn.

Scientists have developed a potential new method for corrective eye surgery that doesn't use lasers, but instead shapes the eye's outer surface using an electrical current.

The method has so far been tested only in animals, but the researchers who pioneered it hope that it will someday offer an alternative or complement to conventional LASIK surgery. The team presented their findings Aug. 18 at the American Chemical Society's annual meeting in Washington, D.C.

LASIK is the most popular type of "refractive" laser surgery, which adjusts how light passes through the clear outer layer of the eye, or cornea. It can correct the changes in the cornea that cause nearsightedness, farsightedness and astigmatism. For those looking to ditch glasses or contact lenses, LASIK has become a common solution: since its approval in 1999 this surgery has treated more than 10 million people in the U.S.

The cornea bends light to focus it on the retina, the light-sensitive tissue at the back of the eye, before the visual information is sent to the brain to be processed. Irregularly shaped corneas don't focus light properly, resulting in impaired vision. While LASIK can correct this irregularity, it can have some potential side effects like eye pain and irritation. More rarely, incisions on the eyes made by lasers can compromise the organ's structural integrity.

To find another possible method to reshape the cornea without lasers or incisions, Michael Hill, a chemist at Occidental College in Los Angeles, and Dr. Brian Wong, a surgeon at UC Irvine School of Medicine, began experimenting with a process called electromechanical reshaping (EMR) to mold tissues in the body. This technique previously enabled the researchers to reshape rabbit ears and alter scars on pigs' skin, approaches that they plan to develop for eventual use in human patients.

Related: How do screens damage your eyes?

EMR uses electricity to alter tissues. Many collagen-containing tissues in the body, including the cornea, are held in place by oppositely charged components attracted to each other like magnets. These tissues also contain water, so zapping the tissues with electricity ultimately lowers their pH, making them more acidic. With the pH altered, the attraction between opposite charged components is unlocked, loosening up the tissue and making it moldable. When scientists then cut the electricity and restore the tissue's original pH, it locks back into the new shape.

Hill and Wong wondered whether EMR could be used to reshape the cornea. To see, they ran tests with rabbit eyes in lab dishes. They created a platinum contact lens template to imitate the corrected shape of a cornea, placed it over a rabbit eyeball in saline solution, and sent an electric current through the platinum lens. Within about a minute, the rabbit eyeball's cornea molded around the contact lens; the whole process took about the same time as LASIK surgery.

The researchers tested this method on 12 rabbit eyeballs, 10 of which were treated as if they had myopia, or nearsightedness. The treatment successfully reshaped the cornea in a way that would better focus light on the retina, and the cells in the eyeballs were not damaged in the process.

The method might also be able to reverse cloudiness in the cornea, Hill and Wong told Live Science, which is currently only treatable through a corneal transplant. That's something they're still experimenting with, but in theory, tweaking the pH of the cornea could also help counter the cloudiness, they think.

Although Hill and Wong are hopeful about the promise of EMR eye treatments, this procedure is in very early stages, they said. The next steps are studies in living animals, and more specific tests to assess which specific vision issues this process can correct, like near- and farsightedness and astigmatism.

"Like any other medical technology it's a process, and you have to go through a fair amount of testing," Wong told Live Science. This includes testing more with animal tissues and with live animals, resolving any issues that arise, and eventually moving on to various phases of clinical trials in humans.

These early preclinical tests of the method are promising in that they show the procedure is safe for eye cells and that the cornea remains clear after EMR alteration, Maria Walker, an optometrist at the University of Houston, told Live Science. But further testing would need to investigate possible longer-term effects. "It might be safe and the cornea might be clear, but then what happens in a month?" said Walker.

Some issues with laser eye surgery, although rare, come from heat transfer to the cornea, which EMR techniques would avoid, Walker noted. "My impression is cautiously optimistic," she said. "I think it's promising."

If the method is proven to be successful and safe in humans, it could someday offer an alternative or complement to LASIK that's possibly reversible — since it's not actually removing any tissue, just rearranging it — and cheaper, the researchers suggest.

"You can't treat every single problem of the cornea with LASIK, there are areas where it simply doesn't have application," said Wong. There are certain patients who aren't good candidates for LASIK. "So I think there are areas where this would have value complementing LASIK."

The cost of EMR equipment would also be cheaper than laser equipment, said Wong, which could potentially make it accessible to more patients looking to correct their vision.

This article is for informational purposes only and is not meant to offer medical advice.

In a first-of-its-kind experiment, doctors in China transplanted a lung from a genetically modified pig into a brain-dead person.

Similar experiments involving brain-dead patients have previously taken place in the U.S., but they involved different pig organs, such as kidneys and hearts, and a previous experiment in China involved a pig liver. These experiments have paved the way to transplants of pig organs into living human patients, although only a handful of those procedures have been performed so far.

The recent experiment, described Monday (Aug. 25) in the journal Nature Medicine, took place in Guangzhou, China, and involved a 39-year-old male who had been declared brain-dead prior to the procedure. The team confirmed that the patient was brain-dead through four different assessments and gained written informed consent from his family to perform the experiment, according to the report.

This is the first time doctors have attempted to transplant a lung from another species into a human — a procedure known as lung xenotransplantation.

"For our team, this accomplishment is a meaningful beginning," study co-author Dr. Jiang Shi, a doctor in the department of organ transplantation at the First Affiliated Hospital of Guangzhou Medical University, told STAT. "Lung xenotransplantation presents unique biological and technical challenges compared to other organs." The aim of the study was to investigate how the human immune system might react to such a transplant, "not to claim clinical readiness today," Shi added. In other words, the technique is not yet ready for prime time in living patients; it's still in preclinical investigation.

Once transplanted, the pig lung "maintained viability and functionality" for nine days, even though it showed signs of rejection as early as 24 hours after the procedure. The experiment ended on Day 9 at the request of the patient's family. From the report, it's unclear how much longer the lung might have lasted had it been left in for longer, but the organ had accrued damage by Day 9.

Related: Can you transplant an organ more than once?

"Nobody would sign up for a nine-day lung transplant," Dr. Adam Griesemer, a senior member of the xenotransplantation team for NYU Langone's Transplant Institute who was not involved in the procedure, told CNN. That said, "I think it is very important to do these studies [in brain-dead people] since you can't assume that the animal models are going to perfectly reflect what happens in human recipients," Griesemer added.

The experiment involved a lung from a pig that had been genetically modified using the gene-editing technology CRISPR; a company called Clonorgan Biotechnology in Chengdu, China, handled the editing. Three of the pig's genes were disabled so that the proteins for which they code wouldn't activate the human immune system; three human genes were also added in an attempt to make the organ more tolerable to a human body.

In May 2024, the transplant team removed the left lung of the pig and transplanted it into the brain-dead patient, who retained his right lung. Immunosuppressive drugs were introduced to the patient's body starting one day before the procedure and were given daily following the operation.

The patient's body didn't show signs of "hyperacute rejection," which would have taken place immediately after the transplantation if it did manifest. Although the lung made it over that initial hump, signs of rejection began to emerge around the 24-hour mark, marked by swelling and inflammation. The immune system generated antibodies against the organ by the third day after the operation, resulting in some damage to the lung.

The researchers suggested that for future attempts at this type of experiment, it might help to block the action of specific immune cells, as well as to suppress certain signaling molecules that ramp up inflammation. The lungs present a huge challenge because, given that they're constantly exposed to air from outside the body, they carry many proteins geared toward immune defense — this paradoxically makes them an easy target for the host immune system to see as "foreign." Additionally, their tissue that exchanges oxygen and carbon dioxide is very delicate, meaning any immune attacks launched against them pack a punch.

Other questions remain about how to improve upon the approach and how well it could work for a living patient. Based on the current study, for instance, it's unclear how well the pig lung could have supported the patient if he was removed from life-support machines, Dr. Richard Pierson, a thoracic transplant surgeon at Massachusetts General Hospital in Boston who was not involved with the recent procedure, told Science News.

"Future studies can refine the approach to lung xenotransplantation and move closer to clinical translation," the study authors concluded. "This study provides crucial insights into the immune, physiological and genetic barriers that must be overcome, and paves the way for further innovations in the field."

The patient: A 38-year-old woman in New Delhi

The symptoms: The patient had given birth via emergency cesarean section in another country, and after the operation, she noted pain on the right side of her lower abdomen. Doctors at the time told her it was normal postoperative pain, and they didn't explore it further. Eventually, a lump formed at the site, and the woman's pain intensified.

What happened next: Four years after her C-section, the patient sought further medical advice at a New Delhi hospital in 2014. Doctors did an ultrasound and CT scan, which revealed a cyst at the site of pain. However, they could not yet tell what lay at the cyst's core. Their first guess was that it was a mesenteric cyst, a type of benign tumor that can cause discomfort and pain.

To confirm this potential diagnosis, they turned to MRI. This created more confusion because it revealed what appeared to be a thick membrane at the core of the mass. Rather than a benign tumor, the doctors now suspected the cyst encased a tapeworm, which could have entered her body if she had eaten food contaminated with tapeworm eggs, for instance.

The treatment: Having failed to identify the contents of the cyst via multiple imaging techniques, the doctors decided to surgically remove the mysterious mass and relieve the woman of her pain. This operation required them to cut off a part of the small intestine, to which the cyst had fused. The patient recovered successfully following this procedure and left the hospital seven days later.

The diagnosis: The cyst measured 8 inches (20 centimeters) long — considerably larger than a typical mesenteric cyst, which is normally no bigger than 2 inches (5 cm) in diameter. Upon opening up the cyst, the doctors discovered a surgical sponge embedded in its center, which they concluded must have been left there accidentally during her C-section.

The immune system treats foreign objects in the body as a threat and tries to break them down and remove them. However, because the sponge could not easily disintegrate, the body's defenses instead encased it in a cyst to conceal the potential threat, doctors concluded in a report of the case.

(Sponges used in surgery should be sterile, so that may help explain the woman's lack of infection; that said, infections and septic shock have occurred in other, similar cases.)

What makes the case unique: Surgeons rarely leave behind a sponge or other object in a patient's abdomen following an operation — a complication known as gossypiboma — but it does happen in about 1 in 1,500 to 1,000 surgeries, estimates suggest.

A simple mistake like this can occur if doctors need to operate in a rush; if surgical teams change partway through the operation; or if the medical staff lose track of how many sponges have been used over the course of a procedure. Sponges are necessary to soak up blood during an operation, but once they turn red, they can blend in with the flesh and become easy to overlook when it is time to close the wound.

Gossypibomas are even harder to detect after the surgery concludes. In this case, the sponge was made of a material that's undetectable on typical scans, so it did not show up with three types of imaging. Following this event, the case report authors recommended that only radio-detectable sponges be used during future surgeries and that the number of sponges present at the start of operation and thrown away are counted to ensure that none go missing inside the body.

This article is for informational purposes only and is not meant to offer medical advice.

A brown bear has received the largest dental crown in history, representatives at the Lake Superior Zoo in Minnesota have revealed.

The bear, named Tundra, fractured one of his four major canine teeth and needed a first-of-its-kind metal crown for protection. A veterinary dentist fitted the specially designed silver-colored cap in a successful hour-long surgery at the zoo on June 23.

"Tundra the Brown Bear just made dental history!" a Lake Superior Zoo representative wrote in an Instagram post. "We're thrilled to share that Tundra has officially received the first-ever full metal crown placed on a bear — and it's also the largest veterinary crown ever created in the world!"

Tundra first fractured his right canine in 2023. The zoo's dentist initially treated the bear by giving him a root canal, but when Tundra later injured the same tooth, the zoo team decided he needed a full coverage crown, according to a statement released by the zoo.

Creature Crowns, a specialist veterinary dental company based in Idaho, created Tundra's new crown from a wax cast of the injured tooth, The Associated Press reported.

Related: Watch polar bear cubs emerge from their winter den for 1st time on Svalbard

The 6-year-old brown bear (Ursus arctos) weighs about 800 pounds (360 kilograms) and, when standing up on two legs, reaches a height of around 8 feet (2.4 meters). For the staff's protection, Tundra was sedated while the new crown was fitted. Lake Superior Zoo's armed response team also stood guard as the veterinary dentist worked, just in case Tundra woke up before his procedure was over — but he didn't, The Associated Press reported.

The surgery was successful, and Tundra is now eating normally again. His new silver full-coverage crown should protect the canine from further injury and bacterial infection.

"He's got a little glint in his smile now," Caroline Routley, the zoo's marketing manager, told The Associated Press.

Editor's note: This article was updated to correct the material used for the bear's crown, from titanium to talladium metal.

General anesthesia is given during surgery to make people unconscious, eliminate pain during the procedure and prevent reflex movements. Many factors are known to impact how anesthesia affects a given person, from their weight and age to whether they have kidney or liver diseases that alter how drugs are metabolized.

But does anesthesia affect males and females differently? And if so, should that change the doses each sex receives?

Current research does hint at some sex-based differences in how general anaesthesia affects patients. However, sex "doesn't drive dosage decisions," Dr. Elisha Peterson, a pediatric pain medicine physician and an associate professor at George Washington University, told Live Science.

She noted that, historically, most research on anesthesia has been done with white, male subjects, and researchers do not yet have sufficient data from female participants of different backgrounds to provide tailored health care based on these factors. As such, a female patient who previously experienced some level of consciousness during surgery would be treated in the same way as a male patient with a similar history: Doctors would monitor the patient's brain waves to monitor how well the anesthetic was working and adjust the dose accordingly throughout the procedure.

Related: How does anesthesia work?

Current guidelines on the use of general anesthesia do not differ by sex, in part because existing research on sex-based differences in anesthesia sensitivity shows mixed results.

For example, data collected after the approval of propofol — one of the most widely used general anesthetics — suggested that men woke up more slowly from the drug than women do. Further research over the years backed up this idea that women emerge faster from general anesthesia than do men, regardless of the drug used.

In addition, a 2023 review of 33 studies suggested that women under general anesthesia had, on average, 38% higher incidences of "anesthesia awareness" than men did. That means they experienced some moments of consciousness, ranging from a dreamlike state to full awareness, despite being under general anesthesia. Although patients recall having some level of consciousness, they do not typically feel pain during anesthesia awareness, according to the American Society of Anesthesiologists (ASA).

Women also woke up from surgery and were able to respond to questions sooner than men did, the 2023 review suggested.

However, some studies, such as this 2002 paper from Thailand, do not report the same pattern. Out of about 800 patients in the study, most of them female, five experienced "intraoperative awareness" — three females and two males. Ultimately, the study authors concluded that inadequate anesthesia was the most likely reason for these five cases.

Peterson noted that differences in male and female physiology, hormone levels and metabolic rates may contribute to differences in the way each sex processes general-anesthetic drugs. Early data from both animal and human research buttress that idea.

In 2024, for example, researchers showed that female mice and adult women took more time to fall unconscious under anesthesia than their male counterparts, and they also woke up faster. Additionally, male mice that were castrated were more resistant to the effects of anesthesia, but upon receiving testosterone injections, became more sensitive to it.

Growing evidence shows that anesthetics modulate the activity of parts of the brain that control the sleep-wake cycle, which are primarily located in the hypothalamus. There's evidence that sex hormones, such as estrogen and progesterone, can affect the sleep cycle, potentially via the hypothalamus. These hormones might also make a difference to how well general anaesthesia works, according to a 2011 study in the British Journal of Anesthesia.

There's also research in mice showing sex differences in the dopaminergic system — major pathways in the brain that rely on the chemical messenger dopamine. This system helps regulate arousal, or wakefulness and attention, and thus may influence how quickly someone wakes up from anesthesia, said Dr. Raveesh Sunkara, a consultant neurosurgeon at Arete Hospitals who was not involved in that past research. However, it's not yet known for sure how those brain differences might actually impact sleep and anesthesia sensitivity.

Again, even though some research hints at sex-based differences, doctors' application of anesthesia does not vary by sex, Peterson emphasized. The overall rate of anesthesia awareness is estimated to be about 1 to 2 per 1,000 medical procedures involving general anesthesia, according to the ASA.

Moreover, there are potential risks associated with increasing anesthetic dosages; for instance, they could lead to dangerous cases of severely low blood pressure, said Dr. Kai Rabenstein, an anesthesia adviser at SEDSConnective, a charity supporting individuals with hypermobility, neurodivergence and associated conditions.

Until further research sheds light on concrete and actionable sex-based differences, some measures could be taken to reduce incidents of anesthesia awareness in women, Peterson suggested. For example, providers should use brain-monitoring tools more frequently for procedures with a high risk of anaesthesia awareness, such as emergency Caesarean sections.

In addition to analyzing the patient's history with anesthesia, it can be worth assessing their alcohol consumption patterns. "Alcohol sensitivity can be taken as a guide," Rabenstein said, as alcohol is metabolized similarly to propofol in the body. That means people with a high alcohol tolerance might also be tolerant to the anesthetic's effects. The ASA also advises patients to inform their doctors of past drug and alcohol use, as it can "increase the risk of anesthesia awareness."

Editor's note: This story was updated on April 29, 2025, to clarify a quote from Dr. Kai Rabenstein.

This article is for informational purposes only and is not meant to offer medical advice.

In an 'extremely rare' case, a person has died from rabies after undergoing an organ transplant in an Ohio hospital.

The unnamed Michigan resident received the kidney transplant at the University of Toledo Medical Center (UTMC) in Ohio, in December last year, Michigan Department of Health and Human Services (MDHHS) spokesperson Lynn Sutfin said in a statement, the AP reports. They died in January 2025.

This marks the first human case of rabies in Michigan since 2009. "Person-to-person transmission of rabies is extremely rare, though it has been documented in a very small number of cases involving organ transplantation," a statement from UTMC reads, as reported by local news WTOL 11.

Rabies is a deadly disease caused by the rabies virus that affects the central nervous system of mammals, including humans. The virus is typically transmitted through the saliva of an infected animal via bites and open wounds, such as scratches.

Related: Can you transplant an organ more than once?

Rabies is almost always fatal once symptoms appear. The time it takes from exposure to symptoms appearing varies from weeks to months, but symptoms usually occur sooner when the wound is closer to the brain. Symptoms initially resemble the flu (fever, headache, weakness) but progress to neurological issues such as confusion, hallucinations, paralysis, hydrophobia (fear of water), and eventually coma and death. Fewer than 20 people have ever survived rabies after symptoms presented, according to the Centers for Disease Control and Prevention (CDC). Around 10 people die from rabies in the U.S. each year, the CDC estimates.

According to the CDC, the vast majority of U.S. rabies cases are a result of exposure to bats, raccoons, skunks and foxes. In the U.S., 7 out of 10 people who die from rabies are infected by bats, while worldwide, domestic dogs cause over 95% of the estimated 70,000 annual human rabies deaths.

The Michigan resident's rabies was confirmed by the CDC Rabies Laboratory. In a statement, the CDC said that the organ donor was exposed to rabies from a wild animal in Idaho five weeks before they died and their organ was transplanted, ABC News reports. The donor had not died with "traditional rabies symptoms," and they had not sought out medical help or notified public health officials after their exposure to the animal.

After an animal bite, rabies can be prevented with post-exposure prophylaxis (PEP). This includes immediately washing the wound with soap and water for at least 15 minutes, and receiving four or five doses of the rabies vaccine over the course of 14 days after the bite. The vaccine helps the immune system produce antibodies against the rabies virus. If the person has never been vaccinated against rabies, they will also receive rabies immune globulin (RIG) on the day of the bite, which provides immediate passive immunity while the vaccine triggers the body's own immune response.

About 800,000 people receive rabies-related medical care from local or state health departments around the U.S. every year.

Several cases of rabies being contracted from a transplanted organ have been reported in the past. A 2005 study in the New England Journal of Medicine reported that four recipients of kidneys, a liver, and piece of an artery died as a result of the donor having contracted rabies from a bat, and a 2020 study in the journal Transplantation revealed that a 5-year-old girl and another recipient died of rabies after a kidney transplant.

Other organ recipients saved

"In addition to the organ donor's kidney, doctors implanted corneal grafts from the donor's eyes into three different patients in three states," the latest CDC statement read. "Based on the concerning symptoms of the kidney recipient who died, CDC worked with Missouri health officials to intercept a fourth corneal graft before it could be implanted into a Missouri resident."

All of the patients who had received transplants of the donor's corneal tissue have since been given rabies post-exposure prophylaxis shots and are in good health, the CDC says.

Cases like this are still extremely rare and should not discourage patients from receiving life-saving organ transplants, Dr. Daniel Kaul, a clinical professor at the University of Michigan's Infectious Disease Clinic who was not involved in the treatment, told local broadcaster WOOD TV8. "The risk of not getting a transplant if you have organ failure is so much higher than this kind of incredibly rare but tragic situation," he said.

While organs are screened ahead of transplantation, testing for rabies and other rare diseases would take several days, whereas donated organs are only viable for transplantation for a matter of hours, Kaul added. However, donors are excluded if they report having rabies or show any visible symptoms of rabies infection.

The MDHHS noted that all health care providers and anyone else exposed to the Michigan transplant patient have been assessed for rabies exposure and given PEP if necessary.

On Independence Day 2020, Nick Kharufeh was enjoying a fireworks display on the street near his aunt's house in California.

Then, within a split second, the fun stopped.

A wayward firework meandered off course and exploded on the ground near Kharufeh, and bits of the explosive struck the cornea of his left eye. The accident left Kharufeh — who was 23 years old, and six years into training to be a commercial pilot at the time — completely blind in one eye.

"My dad was right outside [the house] and it was dark out, so he couldn't fully tell what had happened," Kharufeh told Live Science. "And I was like, 'I feel like I can't see out of my left eye.'"

Related: Gene-therapy drops restore teen's vision after genetic disease left his eyes clouded with scars

At the hospital, doctors initially feared that Kharufeh's eye had been completely destroyed and would need to be taken out. However, after cleaning the debris from his eye, a specialist saw that aside from his cornea, the rest of Kharufeh's eye remained intact.

What followed was months of treatments, involving waking up multiple times in the night to apply medicated eye drops, taking drugs to manage the pain, and undergoing a couple of surgeries, which included cleaning up the remaining debris and an unsuccessful attempt at reconstructing his eyelid.

"It was a rough few months," Kharufeh said. "I didn't leave the house, I didn't tell anybody what happened because I was kind of embarrassed about it — because your eyes are the window to your soul, so I felt like my identity was just gone."

Later that year, Kharufeh's mom told him about an advertisement she'd seen from the Mass Eye and Ear, a Harvard teaching hospital in Boston, Massachusetts. The hospital was seeking volunteers to participate in a clinical trial of a new stem cell therapy for patients with irreversible corneal damage.

The experimental therapy — called "cultivated autologous limbal epithelial cell transplantation" (CALEC) — works by taking stem cells from a patient's healthy eye, growing them into sheets of cells in the lab and then transplanting them into the damaged eye. Once implanted, these new sheets of cells form a surface on which normal tissue can grow back.

Kharufeh decided to make the move to Boston with his mom to take part in the trial, which was starting the following January in 2021.

"At first I was hesitant because they had to do surgery on my good eye, so I was really nervous," Kharufeh said.

But then, immediately after the first of two transplants, Kharufeh saw positive results.

He remembers the moment when he walked into his Airbnb in Massachusetts and could see the bright blue color of his comforter. At that time, he was about eight months out from his firework injury.

"I'll never forget [that moment]," Kharufeh said. "And it sounds so little. It's just like, 'Okay, a little blue comforter.' But in that moment that was everything to me, and I literally cried for so long."

Prior to Kharufeh receiving the new CALEC therapy, the treatment had initially been tested in a small clinical trial of just four patients with corneal damage. That trial, whose results were shared in 2018, marked the first-ever test of a stem cell therapy for the eyes in the U.S., the research team said at the time.

After the small trial demonstrated the therapy's safety and efficacy, the team conducted a larger trial with 15 patients, one of whom was Kharufeh. The findings of the larger trial were published March 4 in the journal Nature Communications, and overall, the treatment was found to be effective at repairing blinding damage to the cornea in 93% of the patients involved. Follow-up trials are still to come and could ensure the treatment's official approval.

Now, at age 28 and five years out from his injury, Kharufeh still lives in Boston where he works in sales for a travel company. The vision from his left eye is not perfect, but he says that the injury doesn't cause him issues during his everyday life. For instance, if he were to cover his right eye with his hand, he would still be able to locate objects and navigate himself around.

In April, he intends to run the Boston Marathon to help raise money for Mass Eye and Ear.

"I think it's given me a whole new life," Kharufeh said of the stem-cell therapy. "Now it's the point where I can actually feel normal."

This article is for informational purposes only and is not meant to offer medical advice.

A new stem cell therapy has repaired blinding damage to the cornea in 93% of patients in an early clinical trial.

The cornea is the clear dome that covers the front of the eye and helps to focus light to enable you to see clearly. On the outer edge of the cornea are stem cells, called limbal epithelial cells, that have the potential to become any other type of corneal epithelial cell. As such, these stem cells can replace any corneal cells that are damaged through injury or normal wear and tear over time.

However, severe injuries, such as those caused by chemical burns or infections, can completely destroy these stem cells, as can Stevens-Johnson syndrome, a condition that can cause blistering of the mucous membranes of the eyes. In these instances, the cornea is permanently damaged, resulting in blindness in the affected eye. Patients with this type of eye damage can't be treated with regular corneal transplants because these use donated tissue to replace only the very center of the damaged cornea. That's opposed to the missing stem cells from the outer edges which are vital for repair purposes.

One potential solution is to restore the lost stocks of stem cells in the patient's damaged eye using healthy cells from their other, healthy eye. In this procedure — known as "cultivated autologous limbal epithelial cell transplantation" — doctors take stem cells from the healthy eye, grow them into sheets of cells in the lab, and then surgically transplant them into the damaged eye.

Related: Gene-therapy drops restore teen's vision after genetic disease left his eyes clouded with scars

The treatment was initially tested in 2018 in a small clinical trial at the Massachusetts Eye and Ear hospital in Boston. The trial involved four patients, each of whom had chemical burns to one eye. This was the first-ever stem cell therapy for the eyes to be performed in the U.S., the team said at the time. The patients were tracked for a year after transplantation, during which time the procedure was shown to be feasible, safe and potentially effective.

Now, the same research team has released the results of a larger trial of 15 patients who were tracked for 18 months following treatment. According to a paper published Tuesday (March 4) in the journal Nature Communications, the patients had blinding cornea injuries from various causes, such as chemical burns, thermal burns or viral infections of the eye.

The treatment was successful in 14 of the 15 patients after 18 months.

Treatment "success" in the trial was defined in three ways, trial runner Dr. Ula Jurkunas, associate director of the Cornea Service at Massachusetts Eye and Ear, told Live Science. Namely, it meant that the surface of the damaged cornea was restored, that blood vessels that once obscured vision in the affected eye had receded, and that the patients experienced less eye pain and discomfort. There were also no serious side effects of transplantation itself. However, one patient developed a bacterial infection unrelated to the treatment.

The team didn't directly measure changes in vision as a marker of success because simply restoring the surface of the cornea with stem cells does not mean that vision will immediately improve, Jurkunas said. If the other layers of the cornea remain damaged, a patient may still need a regular corneal transplant to get their vision back, she clarified.

However, notably, around 70% of the patients showed improved vision at the 18-month mark, she said.

On average, the patients with the most severe corneal damage took longer to respond to the treatment than those with less-severe damage, Jurkunas said. This probably explains why one patient, who had an extensive eye injury, didn't fully benefit from the treatment after 18 months, she theorized.

The new therapy can only treat patients who are blind in one eye, as it relies on using stem cells from their remaining healthy eye. However, in the future, the team would like to develop the treatment so they can use stem cells from organ donors, rather than using patients' own tissues. That way, they'd be able to treat both eyes in patients who need it, but the risk of immune rejection would still need to be considered.

The team will now test whether the therapy works in more people and for longer than 18 months. They also plan to directly compare the therapy to a sham treatment as part of a randomized controlled trial, the gold standard of clinical trials. This will allow them to more reliably determine whether the therapy actually works.

Surgeons in India have removed a parasitic twin from a teenager who had an extra set of legs, buttocks and genitals attached to his chest.

The parasitic twin condition occurs when a conjoined twin stops developing but stays attached to its surviving twin. In this case, the parasitic twin was protruding from the abdomen of a 17-year-old boy and weighed almost 33 pounds (15 kilograms), BBC News reported.

Doctors at the All India Institute Of Medical Science hospital in Delhi detached the parasitic twin during a successful two-hour-long surgery on Feb. 8, according to The Indian Express. Parasitic twins are extremely rare, and this surgery was an exceptional case because they're usually removed when the surviving twin is very young.

"Only 40 to 50 cases of parasitic twins have been documented in world medical literature and, in those cases, the surgery had been attempted on children," Dr. Asuri Krishna, who led the team of doctors in Delhi, told BBC News.

Related: In extremely rare case, doctors remove fetus from brain of 1-year-old

The precise rate at which they occur is unknown, but they're estimated to affect less than one in a million births, according to a 2018 study published in the Journal of Pediatric Surgery Case Reports.

Researchers aren't sure why parasitic twins develop, but they have two main theories based around embryonic fission and fusion — not to be confused with the nuclear reactions of the same name. The fission theory suggests that 13 to 15 days after fertilization, the cluster of cells that form the embryo splits apart, according to a 2010 study published in the Journal of Pediatric Surgery. This is the same process that creates identical twins, except instead of total separation, the two embryos stay partially connected.

The fusion theory argues that two initially distinct inner cell masses join together at a later stage of development, according to the study. Either way, a parasitic twin forms when one embryo stops developing but remains attached to the other twin.

A parasitic twin doesn't survive the pregnancy while the surviving twin fully develops, according to the Cleveland Clinic, a nonprofit medical center in Ohio. In this latest case, the parasitic limbs sensed pain and changes in temperature, BBC News reported. The surviving twin's blood supply feeds the parasitic twin, and the surviving twin can be susceptible to disease and other complications from having to support it, according to the Cleveland Clinic.

Scans revealed that the parasitic twin was attached to the teenager's breastbone with a blood supply coming from a vessel in his chest. The surgeons carefully removed the parasitic twin and then a large cyst that was found in the boy's abdomen.

The teenager's blood pressure dropped dramatically during the surgery because up to 40% of his blood flowed to the parasitic twin. However, the surgeons quickly stabilized him and he left hospital four days after being admitted, BBC News reported.

Living with the parasitic twin was difficult for the teenager, who had dropped out of school. He is now looking forward to a normal life.

"I couldn't travel anywhere or do any physical activity," the teenager told The Indian Express. "Now a new world has opened before me. I hope to study and get a job."

Dwyane Wade, a three-time NBA champion, revealed his diagnosis with kidney cancer on a recent episode of his podcast, "The Why with Dwyane Wade."

The retired basketball player, 43, said he went to the doctor for a full-body check-up in 2023, during which a tumor was found on his right kidney. On Dec. 18, 2023, Wade had surgery to remove the tumor — which was found to be cancerous — along with 40% of that kidney, he said in the episode.

Wade said on the podcast that he was doing "great right now," speaking nearly a year after his surgery.

In the wake of Wade's announcement, here's what you should know about kidney cancer.

What to know about kidney cancer

Located on either side of the torso behind the liver and stomach, the kidneys filter waste and excess salt and water from the bloodstream so that it can be removed from the body in urine. Kidney cancer, also called renal cancer, occurs when cells in the kidney grow out of control, forming tumors. In more advanced stages of the disease, these tumors can spread to additional parts of the body.

Related: New treatment for most aggressive brain cancer may help patients live longer

The most common type of kidney cancer in adults is renal cell cancer, which affects the lining of very small tubes in the kidneys, called tubules, according to the National Cancer Institute (NCI).

In 2024, more than 80,000 people in the U.S. were newly diagnosed with cancer of the kidneys or renal pelvis — funnel-like structures at the center of each kidney that collect urine to transport it to the bladder. Approximately 14,000 people died from the disease, according to the NCI.

It is estimated that roughly 1.8% of adults will be diagnosed with the condition at some point during their lifetime, NCI reports.

However, kidney and renal pelvis cancers have relatively high survival rates. An estimated 78.1% of people diagnosed with the disease survive for five years post-diagnosis — a statistic known as the "five-year relative survival rate." Although kidney cancer made up 4.1% of new cancer cases in the U.S. in 2024, it contributed to only 2.4% of that year's cancer deaths, the NCI estimates.

On the podcast, Wade said of the moment he was diagnosed: "That moment was probably the weakest point I've ever felt in my life." But, "in that process of my weakness, I found strength in my family, in my friends, in my group."

Wade had frequent health check-ups as an athlete, but those regular physicals had come to an end after he retired. He said he was motivated to go back to see a doctor after his father was diagnosed with prostate cancer.

Wade's symptoms at the time included stomach cramps and slow and weak urination, he said. Kidney cancer may not cause any symptoms at first, but in time, other symptoms can include blood in urine, persistent tiredness, recurrent fever, low appetite, unexplained weight loss and a lump or swelling in the kidney area or abdomen, according to the U.S. Centers for Disease Control and Prevention (CDC).

People are more at risk of the disease if they smoke, have overweight or obesity, have high blood pressure, take certain pain medicines for a long time, have certain genetic conditions or have kidney stones. In addition, having sickle cell trait — meaning you carry one copy of the genetic mutation behind sickle cell — or experiencing a long-lasting infection with hepatitis C can raise the risk. Exposure to a chemical called trichloroethylene, used to remove grease from metal, also carries a risk, according to the CDC.

Rates of kidney cancer also increase with age, with the highest rate seen in people ages 75 to 79, based on recent data.

Different treatment options are available depending on the stage of the cancer. Wade underwent surgery to physically remove his tumor and some of his kidney — called a partial nephrectomy — but in other cases, the entire kidney may be removed.

Alternatively, doctors can use radiation therapy against later-stage kidney cancer, which uses high-energy x-rays to kill cancer cells — or they may use immunotherapy, which aims to help the body’s immune system identify and fight the cancerous cells itself.

The podcast episode was recorded at a men's health retreat called TimeOut. Earlier in the conversation, Wade encouraged men to take time to focus on their own health and to "check in" on their male friends and relatives.

A woman with a failing heart has been kept alive with the help of a new "breakthrough" stem-cell technology, scientists report.

The 46-year-old woman had experienced a heart attack in 2016 and subsequently developed severe heart failure, in which the heart cannot pump blood efficiently enough to meet the body's needs. The patient was awaiting a heart transplant when she underwent the experimental stem-cell procedure as part of a clinical trial.

During the surgery, the woman's heart was implanted with tiny patches of heart muscle cells, which had been grown from stem cells in a lab. These 10 patches, each comprised of about 400 million heart cells, kept the woman stable until she could receive a heart transplant three months later, according to a paper published Wednesday (Jan. 29) in the journal Nature.

"We now have, for the first time, a laboratory-grown biological transplant available which has the potential to stabilize and strengthen the heart muscle," study co-author Dr. Ingo Kutschka, a heart surgeon at University Medical Center Göttingen in Germany, said in a press conference, Nature News reported.

Related: In a 1st, baby's heart defect successfully treated with injected stem cells

Unlike many other cell types, such as skin cells, heart muscle cells cannot easily regrow or repair themselves if they are damaged by an insult like a heart attack. Such damage to the heart can lead to heart failure, which affects around 6.7 million adults ages 20 and older in the United States, according to the Centers for Disease Control and Prevention (CDC). Heart failure was listed as a contributing or primary cause of death on more than 450,000 death certificates in the U.S. in 2022, the CDC reported.

Over half of people with severe heart failure die within a year unless they receive a heart transplant, but there are limited donor hearts available, Nature News reported.

To supplement these limited heart transplants, scientists have experimented with transplanting heart muscle cells instead. In the new Nature paper, the researchers describe a method of growing heart tissue from stem cells known as induced pluripotent stem cells (iPSCs). Scientists create these stem cells by gathering normal adult cells and then reprogramming them back into a "pluripotent" state, from which they can develop into almost any cell type in the body.

The scientists encouraged these iPSCs to develop into heart muscle cells and connective tissue in the lab; the researchers then mixed the resulting tissue with collagen to create tiny patches that could be implanted onto the surface of the heart.

"The graft is basically outside of the heart," Dr. Jianyi Zhang, an iPSC bioengineering expert at the University of Alabama at Birmingham who was not involved in this study, told Nature. "It's quite a breakthrough."

The scientists first tested similar patches on rhesus macaque monkeys (Macaca mulatta) with heart failure; the patches tested on monkeys were grown with monkey stem cells. Six months later, several of the monkeys grew thicker heart walls that could pump up to 10% more blood per heartbeat than a group of untreated monkeys.

During the patch procedure, the monkeys were all given immunosuppressant drugs, to prevent their immune systems from rejecting the grafts. Additionally, none of the monkeys developed tumors or irregular heartbeats, which had been a problem in similar studies conducted in the past.

The success of the monkey trial enabled the trial in human volunteers, one of whom was the 46-year-old woman. After the woman underwent her heart transplant, the researchers examined her old heart and saw that the implanted patches had grown minuscule blood vessels, indicating that they were receiving blood and oxygen from the body.

"This is clear now, that you can add muscle to the failing heart, and that we can do that without safety concerns," study co-author Wolfram-Hubertus Zimmermann, a pharmacologist at University Medical Center Göttingen, said in the press conference.

The eventual hope is that this approach will help people stay alive for long enough to receive a donor heart; it's not intended as a complete alternative to transplants.

In an ongoing trial, the scientists have so far implanted the patches in 15 other people. They are also experimenting with more macaques to find a way to minimize the use of immunosuppressant drugs, which help prevent rejection but can leave a patient vulnerable to infection and other health problems.

The patient: A 53-year-old man in Germany

The symptoms: A surgeon developed swelling in his left hand near the base of his middle finger. This was the site of an injury he sustained five months earlier while removing a patient's malignant abdominal tumor. The lump in the surgeon's hand measured 1.2 inches (3 centimeters) in diameter.

What happened next: The surgeon had the lump removed, and an analysis revealed that it was a cancerous fibrous histiocytoma, a type of tumor containing histiocytes — immune cells that migrate into tissues where they don't belong and then form tumorous growths. It was the same type of tumor that the surgeon had been removing at the time of his hand injury. According to a report of the case published in 1996, a pathologist who examined both people's tumors wondered if the pair were as identical as they appeared.

The diagnosis: It turned out that the surgeon had accidentally transplanted some of the patient's tumor into his hand. Researchers collected samples of both tumors, isolated their DNA and conducted a genetic analysis. They found that the tumors not only had similar cellular compositions but were also genetically identical. When the scientists compared the samples to an unrelated histiocytoma, they confirmed that the first two tumors were indistinguishable from each other and "clearly distinct" from the third.

During that prior operation on the abdominal tumor, the surgeon had nicked his palm. The wound was immediately cleaned and bandaged, but the appearance of an identical tumor in his hand months later suggested that the surgeon had accidentally transplanted cells from the patient's malignant growth into his body.

The treatment: The surgeon's tumor was entirely removed via surgery. Two years later, he was in good health. There were no signs that the tumor had spread or was returning.

What makes the case unique: Transplanted tissue that differs genetically from the host's tissue is typically targeted and destroyed by the host's immune system — that's why immunosuppressive drugs are used during organ transplants. The surgeon developed inflammation around his cut, but this immune response didn't stop the tumor from growing. Cancerous cells may have evaded the surgeon's immune system by not producing sufficient antigens — substances that provoke the immune system — to trigger it to make tumor-destroying antibodies, according to the report.

Although this accidental tumor transplant was highly unusual, sporadic cases of cancer being unintentionally transmitted through an organ transplant have been documented for decades, researchers reported in 2013.

This article is for informational purposes only and is not meant to offer medical advice.

Last month, a woman became the third living person to receive a pig kidney. Now, her kidney function is completely normal, and she's off dialysis.

The transplant recipient — Towana Looney, 53, of Alabama — had donated a kidney to her mother back in 1999. A few years later, though, she developed high blood pressure associated with preeclampsia during pregnancy. The condition led her to develop chronic kidney disease, and she needed to start dialysis in 2016. Dialysis does the work of the kidneys by removing waste and extra fluid from the blood.

In 2017, Looney was added to the transplant list, and as a previous kidney donor, she was given higher priority than the average person would be. However, finding a kidney that "matched" Looney's immune system proved extremely challenging.

"Through exposure to other people's tissue, through pregnancies and blood transfusions, she has become sensitized to nearly every tissue type in the population, making it nearly impossible to find a kidney match," Dr. Robert Montgomery, director of the NYU Langone Transplant Institute and leader of Looney's procedure, said at a news conference Tuesday (Dec. 17). "She was waiting for a 1-in-a-million match."

Related: Creating 'universal' transplant organs: New study moves us one step closer.

But Looney had another option: an experimental procedure to get a new kidney from a gene-edited pig.

Now, three weeks out from receiving the kidney, Looney said she's full of energy and feeling grateful.

"Emotionally, I'm overjoyed," Looney said at the news conference. "I don't know what I want to do next, what I want to eat next, where I want to go." She later added, "I want to go to Disney World."

Once the kidney was hooked up to the bloodstream, "it functioned essentially exactly like a kidney from a living donor," said Dr. Jayme Locke, a transplant surgeon at the University of Alabama at Birmingham who studies animal-to-human transplantation and initiated Looney's application for a pig kidney.

Looney's new kidney came from Revivicor Inc., a subsidiary of United Therapeutics. The company tweaked the donor pig's genetics to remove pig genes and add human ones. Looney is the first living patient to receive a kidney with 10 gene edits; the two previous recipients received kidneys with just one gene removed. The 10-edit kidney has been tested in brain-dead organ donors before, so scientists have a sense of how the human body reacts to it.

Genes for three pig proteins that could set off the human immune system were removed, along with a gene for a pig growth hormone receptor. Six human genes were added, in hopes of making the kidney more compatible with the human body.

While Looney carried a high concentration of antibodies that would have attacked a human kidney, tests suggested that her levels of antibodies that might have attacked the pig organ were "pretty modest," Montgomery said.

Transplant rejection, in which the patient's immune system attacks the transplanted organ, is generally more likely in pig-to-human transplants than in human-to-human ones, Montgomery said. But the emergence of rejection doesn't necessarily mean a patient loses the organ — it means doctors might have to quickly apply strong, immune-suppressing drugs to get the reaction under control, he noted.

Looney will stay near NYU Langone's facility for the next three months so she can be monitored daily for signs of rejection, kidney function issues, and any signs of infection from the pig organ.

A pig virus may have contributed to the death of the person who got the first-ever pig heart transplant, so the transplant team will watch closely for such germs. Looney's kidney was negative for known pig viruses that can sicken humans, Locke noted, but her blood will be monitored for signs of infection nonetheless. Looney is also wearing various health trackers to monitor her physical activity, heart rate and blood pressure.

The NYU team plans to launch a formal clinical trial of the 10-edit pig kidney next year, Locke said. And eventually, they will also run a trial of the single-edit kidney, in part to see which option will suit different patients best.

"I want to give courage to those out there on dialysis — I know it's not easy," Looney said. "And it's not the only option. There's hope."

This article is for informational purposes only and is not meant to offer medical advice.

Ever wonder why some people build muscle more easily than others or why freckles come out in the sun? Send us your questions about how the human body works to community@livescience.com with the subject line "Health Desk Q," and you may see your question answered on the website!

Zapping the vagus nerve promotes blood clotting, new research suggests.

These findings are the first evidence in humans of a "neural tourniquet," or a brain-based pathway that could reduce bleeding, said study co-author Dr. Jared Huston, a trauma surgeon at the Feinstein Institutes for Medical Research at Northwell Health in New York.

If a future clinical trial directly shows that the nerve stimulation decreases blood loss, the technique could be used before planned surgeries to protect patients from excessive bleeding, Huston told Live Science.

Around 1.5% of surgeries are complicated by haemorrhaging, or excessive blood loss, and some degree of bleeding is associated with all surgeries. Surgeons currently rely on sutures, bandages and tourniquets — devices that stop blood from flowing to part of the body — to staunch bleeding.

But Huston wondered whether making blood less likely to escape in the first place would make surgery safer. "Preventing a problem is always better than dealing with it after the fact," he said.

Related: How much blood is in the human body?

Huston and his collaborators first wondered if the vagus nerve might promote blood clotting nearly 20 years ago, after the nerve was found to modulate inflammation. The vagus nerve, which originates in the brain and branches out to other organs, controls the parasympathetic nervous system — the rest-and-digest counterpart to the "fight-or-flight" sympathetic nervous system.

Initial experiments in mice and pigs showed that stimulating the vagus could, indeed, reduce blood loss following a small cut. "We then spent the better part of a decade trying to figure out exactly how it works," Huston said.

Last year, Huston's team showed that vagus nerve stimulation activates a type of immune cell, called T cells, in the spleen, the organ that helps filter germs and old cells out of blood. These T cells then activate platelets in the spleen; platelets are the cell fragments that set off blood clot formation.

Upon re-entering circulation, the primed platelets are better able to respond to injury-related cues. In mice with hemophilia, a disorder in which blood can't clot properly, nerve stimulation reduced bleeding, the team found.

To test whether the same mechanism existed in humans, Huston's team collaborated with the Dallas-based biomedical company Five Liters to recruit healthy volunteers. They used an approved device to zap the auricular branch of vagus nerve, which runs behind the ear, for 30 minutes in each person. They collected blood samples before and after the treatment.

Following vagus nerve stimulation, the volunteers' blood contained higher levels of markers of blood platelet activation.

These results, presented in October at the Society for Neuroscience conference in Chicago, showed for the first time "that there is a neural tourniquet pathway in humans," Huston said. "And it appears that we can activate this neural tourniquet pathway non-invasively." More details of the trial can be found at ClinicalTrials.gov.

While the past study results in animals are "very intriguing," more work needs to be done to show vagus nerve stimulation can actually stop bleeding in humans, Peder Olofsson, a professor of bioelectronic medicine at the Karolinska Institute in Stockholm, Sweden, told Live Science.

"Ultimately, measurements of bleeding times, bleeding volumes, and patient outcomes will be key" to demonstrating the clinical value of activating the vagus nerve through the skin, said Olofsson, who was not involved in the study.

Huston agreed. "The next study will have to be in an actual clinical disease where the patients are bleeding one way or another," he said.

Another issue is showing that the stimulators can produce consistent results, Olofsson noted. "Non-invasive stimulators" — while much quicker and easier to use than implanted stimulators — "often show less consistent physiological effects."

Vagus nerve stimulation is already widely used in epilepsy and depression, so the risk of side effects is likely low, Huston added. If his findings can be replicated and extended in larger trials, surgeons might use a brief period of vagus nerve stimulation prior to planned surgeries.

"We administer antibiotics, so you don't get an infection during surgery. We administer pain medications pre-emptively, so the pain is less," Huston said. "What is missing is any way to take a normal, healthy person who's undergoing surgery to try and prevent bleeding ahead of time. That's an enormous unmet need."

Editor's note: This story was updated at 3 p.m. on Dec. 3, 2024 to note that the results were presented at the Society for Neuroscience conference.

Ever wonder why some people build muscle more easily than others or why freckles come out in the sun? Send us your questions about how the human body works to community@livescience.com with the subject line "Health Desk Q," and you may see your question answered on the website!

Women are more likely than men to die of complications from high-risk cardiovascular surgery, a new study finds.

These life-threatening complications, such as heart attacks and infections, were more likely to be recognized too late in women than in men, resulting in the higher death rate seen in women. Not recognizing or responding quickly enough to complications is referred to as "failure to rescue" by doctors.

The new study, published Oct. 16 in the journal JAMA, analyzed the medical records of more than 860,000 patients who had undergone high-risk surgical procedures between October 2015 and February 2020. All of the procedures involved the heart or blood vessels, including surgeries to repair aneurysms, heart bypass surgeries, and heart-valve replacements.

Overall, about 15% of these patients experienced some complication following their procedure; a similar rate of complications was seen in men and women. But, of the overall group, nearly 11% of the women died of complications, compared with 8.6% of the men. The researchers concluded that this difference was likely caused by delays in doctors recognizing and treating women's complications, which included heart attacks, blood clots in the lungs, kidney failure, lung failure, pneumonia, hemorrhage and surgical-site infections.

Related: Scientists developing new 'heart-on-a-chip'

Dr. Mario Gaudino, a cardiac surgeon at Weill Cornell Medical Center and New York Presbyterian Hospital who was not involved in the research, described the study as a "wake-up call" to the long-overlooked disparities in men's and women's outcomes after major surgeries.

Notably, women in the study were also more likely to receive care at teaching hospitals and larger, high-volume hospitals, compared with men. These types of facilities are associated with better-quality care than other medical centers, such as low-volume hospitals — however, women's higher death rate was consistent across all the different facilities.

"If anything, these results show how pervasive the problem is," said Dr. Catherine Wagner, a cardiac surgery resident at the University of Michigan and lead author of the study. "This suggests there is a systemic problem contributing to the under-recognition and under-treatment of women's postoperative complications," Wagner told Live Science in an email.

The study does not draw any definitive conclusions about the factors that might be driving this disparity. Previous research has focused on women's tendency to get surgery at older ages than men, which means they may be dealing with more underlying medical conditions and be at a more advanced stage of disease. These characteristics were reflected in the women in the new study, who, on average, were a bit older and had a slightly higher rate of comorbidities than the men.

However, while these are relevant factors, they fail to fully account for the study's results, which found a much higher death rate among women despite men and women having similar rates and types of complications, said Dr. Andrei Churyla, a cardiac surgeon at Northwestern Medical Group in Chicago who was not involved in the study.

Unconscious bias against women may be one possible explanation, he said. There's a tendency for medical providers to dismiss women's pain, which can delay, or even preclude, proper diagnosis and treatment. A 2022 study in the Journal of the American Heart Association found that young women who complained of chest pain had a 29% longer wait time for heart-attack evaluation than young men, for example.

A lack of understanding of the female heart also may factor into patients' outcomes, Gaudino suggested. "As cardiovascular physicians, I think we've had the wrong approach of thinking that women were actually like men, or just small men," he said. "The mistake we make is to keep treating women with approaches we know work for men."

Until recently, much of the research on cardiac surgery has focused overwhelmingly on male populations, and few studies have been conducted specifically in female patients, Gaudino said.

Additionally, the diagnostic criteria for complications were developed based on data from male patients, so these may fail to account for differences in women's baseline physiology and how these complications manifest in them. As an example, high levels of troponin, a protein in heart muscles, signal a heart attack is coming on — but the cutoff for what counts as "high" was derived mostly from men, who have higher baseline troponin levels than women, he said.

Gaudino suspects the female body is still misunderstood by physicians and that this means complications that would be flagged easily in male patients are more likely to go unnoticed, and thus untreated, in female patients.

There's been a recent effort to shore up research in this area to better understand and address the gap in surgical outcomes between men and women.

"I think we have to constantly remind ourselves that women are different from men," said Dr. Brittany Zwischenberger, a cardiac surgeon at Duke Health in Durham, North Carolina. "And our current focus on sex and gender will hopefully result in tailored approaches to surgery and their postoperative course, and ultimately reduce disparities. But really, this [study] is an opportunity for us to improve postoperative care for all patients."

This article is for informational purposes only and is not meant to offer medical advice.

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A man developed a "breakdance bulge" on the top of his head after repeatedly practicing headspins, doctors report.

The bulbous lump of tissue, which doctors surgically removed, had become tender to the touch and was associated with a circle of hair loss. These hairless bumps on the head are also commonly called "headspin holes," and more broadly, the condition is sometimes called "breakdancer overuse syndrome."

"Despite 'headspin hole' being known within the breakdancing community, it is scarcely documented in the medical literature," the doctors noted in a paper published Thursday (Oct. 10) in the journal BMJ Case Reports. Based on their results, treating these bumps on the head with surgery "appears to be a successful intervention," the physicians said.

Breakdancing — or breaking, as it's known by practitioners — incorporates power moves that may involve balancing in off-kilter poses or spinning on top of the head, for example. The dancer in this case, a man in his early 30s, had been practicing various types of headspins for more than 19 years. He reported training about five times a week for 1.5 hours at a time; about two to seven minutes of each session would be spent putting direct pressure on the top of his head.

Related: 'Breaking,' aka breakdancing, is in the Olympics for the 1st time — here's the brain science behind it

The man said he noticed a bump, accompanied by hair loss, forming on his scalp. And in the past five years, the bump had grown and become tender to the touch.

"The presence of the lesion and associated discomfort were aesthetically displeasing to the patient, but the protuberance had not hindered the patient from continuing his head-spinning activities," the man's doctors noted.

Upon examining the bump, doctors noted that the skin above it moved easily, suggesting the mass was sandwiched between the skin and the skull. A structural scan of the man's head confirmed this was the case, and it also showed that the skin above the bump and the skull below had grown thicker than the tissues surrounding them.

During surgery, doctors removed the large lump of tissue from beneath the man's scalp. They also shaved the thickened portion of his skull back down to its normal width.

"I have received a lot of positive feedback and people say it looks well done, that I have a nice scar," the patient said in a statement included in the case report. "Many say that they no longer notice that I have a bump and that my head looks completely normal."

Although this "breakdance bulge" phenomenon isn't well researched, the studies that do exist suggest that breakers who practice headspins may be prone to hair loss and bumps on the tops of their heads.

This limited literature hints that practicing headspins three or more times a week may come with the highest risk of hair loss, compared with practicing the move less frequently. The hair loss may result from physical trauma or scarring to the top of the head, or from traction alopecia, which happens when hair follicles become damaged from repeated pulling at the root of the hair.

Some reports suggest that headspins may be tied to a heightened risk of lichen planopilaris, an inflammatory condition in which immune cells attack hair follicles, causing balding.

Data suggest that this circular hair loss doesn't always come with a painful bump. In a German study of around100 breakers, about 60% had experienced some kind of overuse injury to the tops of their heads. Of those cases, about 31% had hair loss and 24% developed painless bumps on their heads. About 37% had scalp inflammation.

Notably, "publications regarding this condition are scarce," the doctors said in their report. So the exact prevalence of headspin holes among b-boys and b-girls is unclear.

"This case report represents a pioneering effort in detailing a clinical instance of 'headspin hole,'" the authors concluded.

This article is for informational purposes only and is not meant to offer medical advice.

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Scientists have fixed a hole in a monkey's retina with a patch derived from human stem cells.

This feat — described in a study published Oct. 3 in the journal Stem Cell Reports — is a step forward in retinal transplantation. The retina is the layer of light-detecting cells in the back of the eye, and damage and disease to the tissue can cause vision loss and blindness. Such conditions can be difficult to treat. Sometimes doctors can move part of the patient's own retina from its outer edges to the center, but this inevitably leads to blind spots in the periphery.

The new study focused on repairing a macular hole. In this rare condition, a hole develops in the very center of the retina, at the "fovea," which is needed for central vision and sharp focus. Macular holes often occur when the jelly-like substance inside the eye pulls away from the retina, causing tears. About 90% of such cases can be surgically treated, but the remaining 10% can leave patients with blurred vision or blind spots.

Dr. Michiko Mandai, director of the research center at the Kobe Eye Hospital in Japan, has been working for years on developing miniature, lab-grown versions of retinas from stem cells. These retinal "organoids" are sheets of light-detecting cells, derived from stem cells that can be nudged to develop into any tissue in the body.

Related: Scientists develop 'crying' model of human eye tissue

In 2019, Mandai had an opportunity to test these sheets on macular holes: Another lab studying how the eyes and brain process images found that one of their Japanese macaques (Macaca fuscata) could not complete visual tasks. It turned out that the monkey had a macular hole. The lab then transferred the animal to Mandai's lab for surgery.

Mandai and her team grew a retinal sheet from human stem cells and used it to surgically patch the monkey's retina — sort of like applying a patch to torn clothing. The transplant was safe and effective, and the monkey's performance on visual tests improved post-surgery, they reported.

The only complication of the procedure was a mild rejection of the patch, seen four months after the surgery, Mandai told Live Science. Rejection involves the immune system attacking the transplanted tissue, and in this case, the team resolved the problem with steroid injections that suppressed that immune response.

The rejection may have been due to the cross-species nature of the transplant, Mandai said. "Transplantation of human tissue to a human would have less risk of immune response," she suggested.

Six months after the surgery, the researchers surgically removed the monkey's eye to examine the patch. They found that new visual cells — rods, which primarily handle night vision, and cones, which are key to color vision — had developed. However, the team could not confirm that connections had formed between the transplanted cells and the monkey's original cells.

With macular hole, the improvement in vision arises from the eye recovering its structural organization and function after that hole is closed up, Mandai said. "Whether grafted retinal cells can also contribute to visual function is not known yet, but that part is not mandatory," she said. In other words, vision improves by virtue of the hole being closed, not the grafted cells actually helping with visual processing.

Mandai's team is moving forward on using their retinal organoids to treat other conditions. Last year, the researchers reported results from a clinical trial that used the sheets in human patients with retinitis pigmentosa, a genetic condition that causes progressive vision loss. After two years, the grafts had safely integrated into the patients' retinas, and their vision loss progressed more slowly than that of patients who hadn't been treated.

The team is also studying the function of transplanted retinal tissue in animals to learn whether the transplants can host working cells.

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As one of the leading causes of death in the U.S., kidney disease is a serious public health problem. The disease is particularly severe among Black Americans, who are three times more likely than white Americans to develop kidney failure.

While Black people constitute only 12% of the U.S. population, they account for 35% of those with kidney failure. The reason is due in part to the prevalence of diabetes and high blood pressure — the two largest contributors to kidney disease — in the Black community.

Almost 100,000 people in the U.S. are awaiting kidney transplantation. Though Black Americans are more likely to need transplants, they are also less likely to receive them.

Making matters worse, kidneys from Black donors in the U.S. are more likely to be thrown away as a result of a flawed system that erroneously considers all Black donor kidneys as more likely to stop working after a transplant than kidneys from donors of other races.

As a scholar of bioethics, health and philosophy, I believe this flawed system raises serious ethical concerns about justice, fairness and good stewardship of a scarce resource — kidneys.

How did we get here?

The U.S. organ transplantation system rates donor kidneys using the kidney donor profile index, an algorithm that includes 10 factors, including the donor’s age, height, weight and history of hypertension and diabetes.

Another factor in the algorithm is race.

Research on previous transplants shows that some kidneys donated by Black people are more likely to stop working sooner after transplantation than kidneys donated by people from other races.

This brings down the average time a transplanted kidney from a Black donor can last for a patient.

As a result, kidneys donated by Black people are discarded at higher rates because the algorithm downgrades their quality based on the donor’s race.

This means that some good kidneys may be wasted, raising several ethical and practical concerns.

Risk, race and genetics

Scientists have shown that races are social constructs that are poor indicators of human genetic diversity.

Using a donor’s race assumed people who belong to the same socially constructed group share important biological characteristics despite evidence that there is more genetic variation within racial groups than between other racial groups. Such is the case for Black Americans.

RELATED: 'Racism is a global public health crisis': Author Layal Liverpool says racist ideas still pervade medicine, and that hurts all of us

It is possible that the explanation for observed differences in outcomes lies in genetics and not in race.

People who have two copies of certain forms or variants of the APOL1 gene are more likely to develop kidney disease.

About 85% of people with those variants never develop kidney disease, but 15% do. Medical researchers do not yet understand what is behind this difference, but genetics is likely only part of the story. Environment and exposure to certain viruses are also possible explanations.

People who have two copies of the riskier forms of the APOL1 gene almost all have ancestors who came from Africa, especially from West and sub-Saharan Africa. In the U.S., such people typically are categorized as Black or African American.

Research on kidney transplants suggests that kidneys from donors with two copies of the higher-risk APOL1 variants fail at higher rates after transplantation. This could explain the data on Black donor kidney failure rate.

How might this practice change?

Health care professionals decide how limited resources are used and distributed. With that comes an ethical responsibility to steward resources fairly and wisely, which includes preventing unnecessary loss of transplantable kidneys.

Reducing the number of wasted kidneys is important for another reason.

Many people agree to organ donations to help others. Black donors may be disturbed to learn that their kidneys are more likely to be discarded because they came from a Black person.

This practice can further decrease the trust of Black Americans in a health care system that has a long history of mistreating Black people.

Making organ transplantation more equitable could be as simple as ignoring race when evaluating donor kidneys, as some medical researchers have proposed.

But this approach would not account for the observed difference in transplantation outcomes and could result in transplanting some kidneys that are at increased risk for early failure due to a genetic issue.

And since Black kidney recipients are more likely to receive kidneys from Black donors, this approach could perpetuate transplant disparities.

Another option that would improve public health and reduce racial health disparities is to identify the factors that lead to some kidneys donated by Black people to fail at higher rates.

One way researchers are working to identify higher risk kidneys is using the APOLLO study, which assesses the impact of key variants on donated kidneys.

In my view, using the variant instead of race likely would decrease the number of kidneys wasted while protecting recipients from kidneys that are likely to stop working sooner after transplantation.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

A pioneering surgical procedure provides amputees with bionic limbs that are directly controlled by the nervous system, enabling patients to sense the limb's position in space. 

Scientists demonstrated the success of this technique in a new study of seven people who received bionic legs, which was published Monday (July 1) in the journal Nature Medicine. Including these seven, about 60 people worldwide have undergone this type of procedure, which can be used to install either bionic legs or arms. 

"This is the first prosthetic study in history that shows a leg prosthesis under full neural modulation, where a biomimetic gait emerges," Hugh Herr, co-senior study author and a professor of media arts and sciences at MIT, said in a statement. In other words, the synthetic prosthesis is able to fill in for the lost function of the missing limb and thus produce a natural gait.

"No one has been able to show this level of brain control that produces a natural gait, where the human's nervous system is controlling the movement, not a robotic control algorithm," Herr said.

Related: 'You can get the feeling that you are touching another human': New prosthetic device detects temperature

The surgery itself, known as agonist-antagonist myoneural interface (AMI), involves reconnecting muscles in a patient's residual limb after a below-the-knee amputation, in the case that the patient is getting a bionic leg. 

Electrical signals from the central nervous system, which relay instructions for movement, can then pass between these muscles, and be detected by electrodes in a newly installed prosthetic limb. The signals are picked up by a robotic controller in the prosthesis that enables it to control a patient's gait, or way of walking. Signals about the position and movement of a patient's prosthesis are then fed back to the nervous system. 

In a series of experiments described in the new paper, the seven patients who received AMI surgery were able to walk faster than people who received the same type of prosthetic limb, but who had traditional amputations. Some of the patients could even walk at the same rate as people without amputations. They could also avoid obstacles and climb stairs more naturally than patients who underwent traditional amputations. 

Current technology for prosthetic limbs already enables amputees to achieve a natural walking gait, according to the team who conducted the surgery. However, these prosthetic limbs rely on robotic sensors and controllers to actually move in a predefined, algorithmic pattern, the team said. AMI, in contrast, enables the limb to dynamically respond to signals from the body.

"The approach we're taking is trying to comprehensively connect the brain of the human to the electromechanics," Herr said.

The patients who underwent AMI also experienced less pain and muscle atrophy, the scientists reported. 

AMI can also be used for people who have arm amputations, the team said, and the surgery can be done either during a patient's original amputation or at a later date. 

"This work represents yet another step in us demonstrating what is possible in terms of restoring function in patients who suffer from severe limb injury," Dr. Matthew Carty, co-senior study author and an associate professor of surgery at Harvard Medical School, said in the statement.

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Doctors in the U.S. have successfully performed kidney transplant surgery on a man who was awake throughout the whole procedure. 

On May 24, John Nicholas became the first person at Northwestern Medicine in Chicago to receive a new kidney without general anesthetic and to go home the next day. It's not the first time this approach has been used worldwide, but it's far from routine.

The 28-year-old was discharged in under 24 hours, whereas kidney transplant patients would typically remain at the hospital for several days or up to a week.

During Nicholas' surgery, doctors injected anesthetic into the fluid that surrounds the lower spinal cord. At the same time, they lightly sedated him for comfort, according to a statement. Sedation is used to make a patient relaxed and drowsy without causing them to lose consciousness. 

Related: 1st person to receive a pig kidney transplant has died

The surgery took less than two hours, and Nicholas didn't feel any pain. At one point during the procedure, he even got to see his new kidney, which was donated by his best friend, Pat Wise, before it was implanted into his body. 

"That particular moment where I saw the kidney in Dr. Nadig's hands — like [it was] extremely powerful to see that," Nicholas said at a press conference Monday (June 24). Within 24 hours of the procedure, Nicholas walked out of the hospital. 

Nicholas had experienced kidney issues since he was 16, which culminated in the need for a transplant. Lab work revealed inflammation was damaging his kidneys, but its exact cause has not been determined. 

Now, several weeks after surgery, Nicholas is back to being active and can enjoy a less restrictive diet, including being able to treat himself to his favorite pizza, according to the statement. He'd had to limit his salt intake prior to getting surgery because excess salt can have detrimental impacts on kidney function. 

"I've hit 10,000 steps, I think, every day in the last week and I don't do that normally. So definitely doing well," Nicholas said. 

This isn't the first time that spinal and local anesthetic rather than general anesthesia has been used during kidney transplantation, Dr. Satish Nadig, one of the surgeons who performed the transplantation, said at the press conference. Local anesthetic is also used for a range of major surgeries, including joint replacements and cesarean sections. 

However, kidney transplants, which have saved hundreds of thousands of lives in the U.S. alone, are usually performed under general anesthetic. Most patients also have to spend several days to a week recovering in the hospital afterward. This is partly because general anesthesia can temporarily affect a patients' memory, concentration and reflexes. 

This new approach really challenges the "status quo" of kidney transplantation, especially given that Nicholas recovered so quickly after surgery, Nadig said. This status quo has remained more or less the same since the first successful human kidney transplant was performed in 1954, he said. 

Avoiding general anesthesia could potentially reduce patients' hospital stays, which would also reduce the time in which they could potentially pick up hospital-acquired infections. 

The new approach could also make transplant surgery more accessible to patients who are at a higher risk of complications from general anesthesia. This includes older individuals with some degree of cognitive dysfunction or heart or lung disease, Dr. Vincente Garcia Tomas, an anesthesiologist who helped perform the surgery, said at the press conference. Some people are also fearful of going under general anesthesia, and this could offer an alternative option.

Nicholas is young and has few risk factors that increase the likelihood of complications from general anesthesia, the team noted. His decision to participate in this pioneering surgery could eventually help many other patients for whom the procedure might be more dangerous. 

"He put his trust in us and because of John, he's moving the entire field of transplantation forward," Nadig said.

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Ancient Egyptians tried to surgically treat cancer more than 4,000 years ago, researchers have discovered.

In a new study, researchers analyzed a human skull from the University of Cambridge's Duckworth Collection dating to between 2686 and 2345 B.C. The skull contained evidence of a large primary tumor, as well as more than 30 smaller, metastatic lesions. The researchers discovered that these lesions were surrounded by cut marks, possibly made using a sharp object such as a metal instrument. This suggests that ancient Egyptians attempted to conduct surgery to treat the patient, who is believed to have been a man in his early 30s, the researchers said. 

Until now, the oldest-known description of cancer came from around 1600 B.C. Edwin Smith Papyrus from Egypt, which is thought to be a copy of a work from centuries earlier. The text chronicled several breast tumors but underlined that there was "no treatment" for them.

The new findings, which were published Wednesday (May 29) in the journal Frontiers in Medicine, may subsequently shift our conception of when modern medicine began, the authors said. 

Related: Rare tumor with teeth discovered in Egyptian burial from 3,000 years ago

"What we found is the first evidence of a surgical intervention directly related to cancer," study co-author Edgard Camarós Perez, a paleopathologist at the University of Santiago de Compostela in Spain, told Live Science. "This is where modern medicine starts."

The team also analyzed a skull from a woman who was 50 years old when she died and lived between 664 and 343 B.C., whose skull is also housed at the University of Cambridge's Duckworth Collection. Like the man, she had a big lesion on her skull that was suggestive of cancer. However, she had two additional lesions on her skull that were caused by traumatic injuries, such as an attack using a sharp weapon, the team found. 

Both of the traumatic lesions had healed, hinting that medicine in ancient Egypt was advanced enough to treat her trauma — but not her cancer.

The new findings suggest that cancer was a "frontier" in ancient Egyptians' medical knowledge — something they may have tried but failed to treat successfully, Camarós Perez said. However, he acknowledged that without the patients' clinical history, scientists can't paint the full picture of the cancer that they experienced.

Going forward, the team wishes to look even further back in time to learn more about how humans have dealt with cancer over millennia. 

"If we know that more than 4,000 years ago, ancient Egyptians were trying to understand cancer at a surgical level, we are absolutely convinced that this is just the beginning of something that started many, many thousands of years ago," Camarós Perez said. 

The first person to receive a pig kidney transplant has died just two months after he underwent the groundbreaking procedure. 

Rick Slayman, a 62-year-old from Weymouth, Massachusetts, had a genetically modified pig kidney placed in his body as part of a four-hour, pioneering surgery at Massachusetts General Hospital on March 16. 

Slayman had end-stage kidney disease and had previously received a human kidney transplant, which showed signs of failure after a few years. His doctors proposed the experimental pig kidney transplant as Slayman was restarting dialysis and experiencing severe complications. 

The doctors hoped that the pig kidney could last years, CNN reported, but, as such a transplant hasn't been done before, there was uncertainty about how well it would take. Slayman died just weeks after his surgery, but his medical team says there's no evidence the transplant was related to Slayman's death. 

Related: 1st partial-heart transplant growing with baby 1 year later

"The Mass General transplant team is deeply saddened at the sudden passing of Mr. Rick Slayman," the hospital shared in a statement on Saturday (May 11). "We have no indication that it was the result of his recent transplant." The statement did not detail Slayman's cause of death.

As of March 2024, more than 100,000 Americans are on the waiting list for organ transplants, 89,000 of which require a kidney. Each day, 17 people on these lists die. Transplanting genetically modified organs from animals into humans, a process known as xenotransplantation, is seen as a promising new way to potentially address the shortage of available organs from human donors. 

Before Slayman's procedure, scientists had only conducted experimental pig kidney transplants in brain-dead organ donors, as a proof-of-concept for the surgeries. However, since then, another living patient has since received one — a 54-year-old who also received a heart pump along with the pig kidney. 

The first person to receive a pig organ of any kind was a Maryland man who underwent the world's first pig-heart transplant in 2022. He died shortly after the surgery, likely as a result of being infected with a pig virus that triggered an inflammatory response.  

In Slayman's case, scientists used CRISPR gene-editing technology to modify the genes of the donor pig, removing ones that could prompt the human immune system to attack the kidney and adding ones that could help prevent transplant rejection. The patient also simultaneously received antibody-based treatments and immune-suppressing drugs to help prevent organ rejection. 

The kidney itself came from a company called eGenesis, which previously successfully tested the transplant in monkeys. On average, the monkeys lived for around 176 days, or nearly six months, after surgery in these experiments. 

In the hospital's statement, Slayman's family said they were thankful to spend his last few weeks with him. 

"[The medical team's] enormous efforts leading the xenotransplant gave our family seven more weeks with Rick, and our memories made during that time will remain in our minds and hearts," they wrote. 

"Millions of people worldwide have come to know Rick's story," they added. "We felt — and still feel — comforted by the optimism he provided patients desperately waiting for a transplant." 

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In the first medical procedure of its kind, a New Jersey woman received a new heart pump along with a kidney and thymus gland from a pig.

Lisa Pisano, 54, had both heart failure and end-stage kidney disease, the latter of which required regular treatment with dialysis. However, she did not qualify for a traditional combined heart-kidney transplant because she had several chronic conditions that made her a poor candidate. There's a limited supply of human organs, so to qualify for multiple, a person has to meet certain criteria that suggest they'd have a good outcome.

Pisano's doctors at NYU Langone Health began looking into getting her a mechanical heart pump, called a left ventricular assist device (LVAD), which could extend her life. But getting the pump would be very risky while Pisano remained on dialysis, so she'd still have to secure a working kidney. Complicating the matter, the antibodies circulating in Pisano's blood meant she might have to wait years for a human kidney that "matched" her immune system to become available. 

But she didn't have years to wait. "She only had weeks to live," Dr. Robert Montgomery, director of the NYU Langone Transplant Institute, told reporters at a news conference Wednesday (April 24).

Related: 1st partial-heart transplant growing with baby 1 year later

With no human kidney available, Pisano's surgical team instead looked to organs from gene-edited pigs. 

In two procedures conducted over nine days in early April, Pisano received a heart pump and then a pig kidney and a thymus gland. The thymus helps train the body's immune cells, so including the gland should help prevent Pisano's immune system from rejecting the kidney, according to her doctors.

"No LVAD patient had ever received a kidney transplant of any kind — human or pig — and so we didn't know if it would work," Montgomery said. "We have combined two marvels of modern medicine in a novel way," he said. 

When the team pitched this idea to Lisa, "she was gung ho about this from the beginning," Todd Pisano, Lisa's husband, said at the news conference. "I really do hope … that they OK this [procedure] and people can benefit from this type of surgery."

This is also the first time both a pig's thymus and kidney have been transplanted into a living person; NYU had previously tested a similar procedure in a brain-dead organ donor. The hope is that the thymus will not only reprogram Pisano's immune system but also allow her to use a lower dose of immune-suppressing drugs than would typically be needed. The thymus gland itself was embedded into the transplanted kidney.

The pig that both organs came from had been gene-edited such that its tissue lacked a specific type of sugar. Known as alpha-gal, this sugar triggers an immune reaction in humans that would have caused the organ to be rejected. 

This type of gene-edited kidney is relatively simple compared with the kind recently transplanted into a man in Massachusetts. In that case, the man's new kidney came from a pig that had three pig genes removed and seven human genes added. Montgomery said that, due to differences in how each set of pigs is raised, it's likely that these simpler kidneys will be able to enter widespread use more quickly than the complex ones.

Now, 12 days out from her transplant, Pisano's kidney function "is perfect, and she has no signs of rejection," Montgomery said. She'll need time to fully recover in a rehabilitation facility before being discharged, he added.

Like Todd, Lisa hopes that, in the future, more people will have access to this two-pronged procedure. "My goal was to make sure that I'm set up for somebody else — that somebody else sees what I went through and decides to take a leap, take a chance," Lisa said in a video statement released by NYU.

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A man in Massachusetts just became the first person to receive a pig kidney transplant.

Scientists have been developing genetically engineered pigs as a way to address the critical lack of human organs available for transplant surgeries. Several proof-of-concept experiments with such pig organs have been done in recent years; one involved hooking a kidney up to a brain-dead organ donor's body, and another involved performing a double-kidney transplant in a brain-dead patient. In addition, in 2022, a man underwent the first pig-heart transplant but died shortly thereafter.

In this latest medical milestone, surgeons at Massachusetts General Hospital transplanted a pig kidney into a living human patient for the first time. The 62-year-old patient, Richard Slayman, is recovering well after his four-hour surgery on March 16, and he's expected to be discharged from Mass General soon, according to a statement from the hospital.

"I saw it not only as a way to help me, but a way to provide hope for the thousands of people who need a transplant to survive," Slayman said in the statement.

Related: What happens to your body when you're an organ donor?

Slayman, from Weymouth, Massachusetts, has a history of type 2 diabetes and high blood pressure and had been on dialysis for seven years before undergoing a human kidney transplant in 2018. However, five years later, the transplanted organ showed signs of failure. He restarted dialysis in 2023, which caused serious complications that required regular hospital visits to manage.

"He would have had to wait five to six years for a human kidney. He would not have been able to survive it," Dr. Winfred Williams, associate chief of the nephrology division at Mass General and the patient's primary kidney doctor, told The New York Times.

An opportunity arose for Slayman to receive a pig kidney, and after discussing the procedure's potential risks with his doctors, he consented to the operation.

The kidney itself came from eGenesis, a biotechnology company that's developing human-compatible engineered organs. The company uses the famous gene-editing system CRISPR to tweak the genes of its pigs.

To make the organs suitable for people, the scientists snip out three genes involved in making carbohydrates, or sugars, found in pigs that the human immune system attacks. In addition, they add seven human genes that help prevent immune-related domino effects that could lead to transplant rejection. And finally, they disable snippets of viral DNA — called endogenous retroviruses — in pigs' genomes that don't bother the pigs but can hurt humans, according to eGenesis.

In all, the scientists make 69 edits in the pig DNA, CNN reported.

As part of the transplant procedure, Slayman received two antibody-based treatments to help prevent organ rejection, as well as immune-suppressing drugs. The apparent success of the procedure raises the hope that such transplants could one day be common.

"Our hope is that dialysis will become obsolete," Dr. Leonardo Riella, medical director of kidney transplantation at Mass General, told The Washington Post.

Slayman's surgery "also represents a potential breakthrough in solving one of the more intractable problems in our field, that being unequal access for ethnic minority patients to the opportunity for kidney transplants due to the extreme donor organ shortage and other system-based barriers," Williams added in the hospital's statement.

"An abundant supply of organs resulting from this technological advance may go far to finally achieve health equity and offer the best solution to kidney failure — a well-functioning kidney — to all patients in need," he said.

This article is for informational purposes only and is not meant to offer medical advice.

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A tiny, implantable device could detect when tissues in the body spring a leak following gastrointestinal (GI) surgery, and it could do so before those leaks become deadly, new animal research suggests. 

Patients who've had GI surgery — for example, to remove cancer from their stomach or pancreas — can develop leaks in the days after their procedure. This can occur if the tubes that connect organs in the GI tract are not properly resealed afterward. Between 2.7% to 25% of GI surgeries result in leaks, depending on where the tubes are resealed. This leaking fluid can ooze into other parts of the body, triggering infections, and in serious cases, blood poisoning and sepsis.

Doctors usually spot leaks by closely tracking a patient's symptoms and scanning their abdomen using techniques such as computed tomography (CT). However, it can be difficult from these scans to distinguish bodily fluid in its proper place from that which has leaked out of an abdominal organ, say the team behind the new device. 

Their invention, called BioSUM, measures mere millimeters across and is made of tiny metal discs embedded in a gel. The gel changes shape in response to changes in the acidity of its surroundings, and that shape change can be easily seen on an ultrasound. In a preliminary experiment in rats and pigs who'd had GI surgery, BioSUM detected harmful leaks within 10 or 30 minutes of being implanted in the body, respectively. 

Related: 'You can get the feeling that you are touching another human': New prosthetic device detects temperature

BioSUM has yet to be tested in humans. However, the team behind it, who described their findings in a paper published Thursday (Mar. 7) in the journal Science, think it could help doctors detect GI leaks earlier, before patients get dangerously sick. The leaks could then be treated earlier, possibly without the need for antibiotics or admittance to the intensive care unit, the team says. 

"It really impacts the quality of life of the patients that develop these leaks if we can catch it early," Dr. Chet Hammill, co-senior study author and an associate professor of surgery at Washington University in St. Louis, told Live Science. It's also a "huge saving to healthcare costs," since a leak can basically double the cost of a surgical procedure, he said. 

BioSUM is designed to be implanted in the body while a patient has GI surgery. Once surgeons have re-sealed the person's digestive system, the device could be implanted directly on the seals or on nearby tissue. Then, as a patient recovers from their surgery, BioSUM would detect changes in the pH of the tissue around the seal. 

The normal pH range of different organs within the digestive system varies widely. The contents of the stomach, for instance, have a very acidic pH, while fluid in the first part of the small intestine — called the duodenum — has a more alkaline pH. 

The gel in the BioSUM device can be tuned to respond to pH ranges relevant to the organs in which it's being implanted. Then, if fluid leaks from an organ, the gel reacts to the sudden change in pH and swells, pushing the metal discs embedded within it further apart from each other. This movement is what's detectable with an ultrasound device. 

BioSUM would also naturally break down in the body, without needing surgery to remove it. 

In rats and pigs, BioSUM remained stable for two weeks after being surgically implanted onto the animals' GI organs. The device was then able to identify leaks triggered in several GI organs, namely the pancreas, stomach and small intestines, with the help of ultrasound imaging. 

The device degraded on its own with no significant accumulation of zinc — the bioresorbable metal included in the disks — in the animals' vital organs, such as their heart, liver or spleen, or in the blood.   

The researchers now plan to seek approval from the U.S. Food and Drug Administration (FDA) to test the device in people, Hammill said. 

This article is for informational purposes only and is not meant to offer medical advice. 

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Many transgender men and other gender-diverse people opt to take testosterone to bring about male secondary sex characteristics, such as a deeper voice and thicker body and facial hair, and to suppress female characteristics, such as menstruation. While taking this hormone therapy, a person may no longer get their period, however, they may still ovulate and therefore could potentially get pregnant, a new study finds.

The small study included 52 transmasculine people, meaning people who were assigned female at birth but whose gender identity aligns with masculinity; this term can include transgender men and some nonbinary and gender-fluid people, for instance. 

The participants had each taken testosterone for at least a year before getting an oophorectomy, a gender-affirming surgery to remove one or both of their ovaries. After removal, scientists analyzed the patients' ovaries to look for signs of ovulation.

Related: Blood thickening tied to gender-affirming testosterone is rare

None of the study participants were experiencing periods prior to their procedures — typically, testosterone therapy causes patients to stop menstruating within three to six months of use. It is often assumed that when a person taking testosterone stops menstruating, they no longer ovulate, meaning no eggs get released from the ovaries. 

However, the new study found that 33% of the participants showed signs that they were ovulating, irrespective of how long they'd been taking testosterone, how much of it was in their blood or whether they'd used testosterone gel or injections. These signs of ovulation included the presence of fluid-filled sacs where an unfertilized egg develops, or the corpus luteum, a group of cells that form after ovulation and make hormones that support a potential pregnancy.

The findings of the new study, published Thursday (Feb. 22) in the journal Cell Reports Medicine, highlight that transmasculine people on testosterone could still potentially become pregnant, and therefore, patients should use contraception if they wish to engage in sexual activity that could lead to unwanted pregnancy. 

"The physical and mental consequences of an unplanned and unwanted pregnancy are enormous," Joyce Asseler, the co-senior study author and a doctoral candidate at Amsterdam University Medical Centers, said in a statement. "It is important that transmasculine people and their healthcare providers are aware of this risk and act accordingly," she said. 

Prior studies have shown that transmasculine people on testosterone could potentially become pregnant. For instance, a 2020 study showed that 7 of 20 transmasculine people on testosterone therapy had temporary upticks in the levels of a breakdown product of progesterone, a sex hormone that supports menstruation, in their urine. Progesterone levels typically peak after ovulation, suggesting that these individuals were likely ovulating and theoretically could have gotten pregnant. 

But the new study has gone one step further and found direct evidence of recent ovulatory activity in the ovaries of patients on testosterone therapy. 

Future research will need to "delve deeper" into why ovulation occurs in some people who take testosterone and not others, Asseler told Live Science in an email. It is also unclear how this capacity for ovulation might translate into someone's chances of becoming pregnant, Asseler said. 

Nevertheless, the potential for ovulation still highlights the importance of contraception and reproductive counselling in transgender health care, she added.

"It is crucial to address this issue due to the significant physical and mental consequences of an unplanned pregnancy, particularly considering the limited access to reproductive healthcare for transgender and gender diverse individuals worldwide," she told Live Science.  

This is especially pertinent considering that taking testosterone during pregnancy can influence the development of the fetus. Notably, transmasculine people who come off testosterone can carry out a successful pregnancy, should they wish to bear children. 

This article is for informational purposes only and is not meant to offer medical advice.

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Doctors could use distinct patterns of gene activity in the blood to more quickly diagnose and treat children with life-threatening appendicitis, new research suggests. 

These genetic measures could help doctors differentiate between so-called simple and complicated appendicitis at early stages of the disease, researchers wrote in a paper published Monday (Feb. 19) in the journal JAMA Pediatrics. This method of diagnosis could flag which patients should be rushed into surgery and which might be able to be treated through nonsurgical methods, such as antibiotics, they noted.

The appendix is a finger-like tube that extends from the large intestine. If the appendix becomes blocked — for example, by food or feces — disease-causing pathogens can get trapped within it, triggering inflammation. The appendix can then swell and push against nearby blood vessels, reducing blood supply to the organ and causing sharp abdominal pain. 

There are several forms of appendicitis. One is chronic, with milder symptom flare-ups that come and go over weeks, months or years. Another is "acute," involving symptoms that suddenly emerge over 12 to 24 hours and can be life-threatening, requiring immediate surgical removal of the appendix. 

Related: What if humans didn't have an appendix?

One life-threatening complication of appendicitis is that the appendix can burst due to the pressure caused by swelling; this is known as "perforated" or "ruptured" appendicitis. In this scenario, infected fluid can leak into the abdomen and throughout the body, potentially causing blood poisoning or sepsis. If the appendix doesn't burst or develop other complications, patients are described as having "simple appendicitis," which usually requires shorter hospital stays and has a reduced risk of readmission. And in some cases, simple appendicitis can be successfully treated with antibiotics rather than with surgery.

Children are the most likely age group to get appendicitis — but when a child is brought into the hospital, doctors may struggle to distinguish between simple and complicated appendicitis, especially at early stages of the condition. This is because, apart from taking ultrasounds, clinicians have to rely on insensitive lab diagnostic tests and scoring systems that are based on physical symptoms, such as nausea or fever. These measures can result in misdiagnosis, leading to delayed treatment, the study authors wrote. 

In their new analysis, the researchers looked at the gene activity of more than 70 children ages 5 to 17 who were hospitalized with suspected appendicitis in Canada. They found that the kids could be retroactively diagnosed as having either simple or complicated appendicitis based on the level of activity of four genes. The researchers measured the gene activity by looking at the amount of RNA — a molecule used to convert DNA into proteins — in samples of the children's blood taken when they were admitted to the hospital. 

The gene activity analysis delivered an accurate diagnosis 85% of the time. If the test can be used to help doctors reach accurate diagnoses faster, it could help them select the best drugs, namely antibiotics, to prescribe patients and prioritize who receives surgery first, the authors wrote. 

"It is well known that the earlier the physician applies appropriate therapy, the better the outcome," Bob Hancock, co-senior study author and director of the Centre for Microbial Diseases and Immunity Research at the University of British Columbia, in Canada, told Live Science in an email. 

In the case of perforated appendicitis, "a diagnosis would indicate the use of potent antibiotics and supportive therapy as well a triage of the patient into the Intensive Care Unit," he said. 

In a separate analysis, the authors also discovered that children with perforated appendicitis had a dysregulated immune response to infection, similar to that seen in sepsis. This was evidenced by the activity of immune-related genes in their blood. Recognizing that perforated appendicitis shares features with sepsis may help doctors recognize the deadly condition as soon as patients arrive at the hospital, pediatric surgeon Dr. Maurizio Pacilli and biomedical data researcher Rishikesan Kamaleswaran wrote in a commentary of the study. 

That said, while these findings are a "step forward" in our understanding of appendicitis, the newly identified gene markers will need to be tested in more people in large clinical trials before they can be used for diagnoses in hospitals, the commentary authors wrote. 

Future research should also assess whether these tests could feasibly be put into widespread use, taking into account how much they may cost and how long they would take to perform, the commentary authors added. 

This article is for informational purposes only and is not meant to offer medical advice. 

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In a rare case, a girl's stomach folded over on itself, leaving her in crippling pain for two days and in need of emergency medical treatment.

The 12-year-old girl in Ethiopia had developed a rare and potentially life-threatening condition called gastric volvulus, in which all or part of the stomach rotates by more than 180 degrees. This caused her abdomen to become tender and swollen and stopped her from being able to pass stools or breathe properly.

Gastric volvulus kills between 30% and 50% of the patients it affects. It can cause the stomach to become completely obstructed, blocking the movement of food through the organ as well as the flow of blood and oxygen to the stomach and back to the heart, which can result in tissue death. Holes can also form in the folded stomach, causing blood and other fluids to leak out. This makes it even harder for the heart to pump blood around the body and can also lead to blood poisoning.

In the recent case, the girl survived the painful condition thanks to prompt diagnosis and surgical treatment, according to a report of her case, published Jan. 13 in the International Journal of Surgery Case Reports.

Related: 'Complete' twist of fallopian tube sent girl to hospital with sudden belly pain

First described in 1886, gastric volvulus is most often diagnosed in people over the age of 50 or in children under age 1. Although researchers aren't sure exactly how many people experience the condition, it is believed to be extremely rare, with the total number of reported cases running in the hundreds worldwide.

The condition is most commonly caused by a paraesophageal hernia, in which part of the stomach pushes into the chest cavity through an opening in the diaphragm — the dome-shaped muscle that supports the expansion and contraction of the chest during breathing. These hernias, which can be caused by structural abnormalities during development or by traumatic injuries to the diaphragm, can make the stomach vulnerable to twisting.

In the girl's case, her gastric volvulus resulted from the stomach folding over on itself like a clam shell shutting, which occurs in about one-third of patients with gastric volvulus. Such cases are more likely to be seen in young children and are caused by looseness in the ligaments that normally anchor the stomach in the abdomen, the authors wrote in the case report. Specifically, the ligaments that attached the girl's stomach to the horizontal, middle portion of her large intestine were unstable, they wrote.

Gastric volvulus is normally diagnosed using imaging techniques, such as computed tomography (CT) scans or X-rays. However, in the girl's case, the CT scanner in the hospital wasn't working, the case report authors noted. After initial examinations of her abdomen, doctors rushed the girl straight to the operating theater without doing any imaging and diagnosed her in the course of surgery.

Once diagnosed, gastric volvulus is usually treated by surgically untwisting the stomach and securing it to the abdominal wall to prevent any future folding. In high-risk cases, doctors may also relieve the pressure in a patient's stomach using a tube inserted through their nose, as was the case with the girl in this report.

Six days after her surgery, she was able to leave the hospital.

This article is for informational purposes only and is not meant to offer medical advice.

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Thousands of years ago, a woman underwent two surgeries to her head — and survived both procedures, her skull reveals.

Scientists in Spain made the discovery after analyzing the woman's skeletal remains, which were unearthed at a Copper Age burial site known as Camino del Molino, located in Caravaca de la Cruz in southeastern Spain, according to a study published in the December issue of the International Journal of Paleopathology.

The woman, who was between 35 and 45 years old when she died, was one of 1,348 individuals found at the funerary site, which was used from 2566 to 2239 B.C. However, unlike the other skeletons, her skull showed evidence of a series of trepanations, which are surgical procedures that involved drilling or scraping holes through the skull to expose the dura mater, the outermost layer of tissue surrounding the brain and spinal cord, as a form of medical treatment.

Further examination revealed two overlapping holes between her temple and the top of her ear. One opening measured 2.1 inches wide by 1.2 inches long (53 by 31 millimeters), while the second was smaller, at 1.3 by 0.47 inches (32 by 12 mm).

Related: Highest-ranking person in Copper Age Spain was a woman, not a man, genetic analysis shows

Researchers don't think the openings were caused by an injury, based on a few factors. For example, there were no fractures radiating from the lesions, and each hole contained well-defined edges. They concluded that the holes were the remnants of two separate surgeries.

"We identified two distinct holes, resulting from two different interventions," study lead author Sonia Díaz-Navarro, a postdoctoral researcher in the Department of Prehistory at the University of Valladolid in Spain, told Live Science in an email.

Based on the holes, along with the "oblique orientation of the hole walls," the researchers determined that the trepanations were done using a "scraping technique."

"This involves rubbing a rough-surfaced lithic [stone] instrument against the cranial vault, gradually eroding it along all its edges to create the hole," Díaz-Navarro said. "To perform this surgery, the affected individual likely had to be strongly immobilized by other members of the community or previously treated with a psychoactive substance that would alleviate pain or render them unconscious."

Amazingly, the woman appears to have survived both operations, evidenced by healed bone in her skull. Researchers think she lived several months after the second surgery.

Documentation of prehistoric surgical procedures is a "rare occurrence," especially on this area of the head, known as the temporal region, Díaz-Navarro said. In the Iberian Peninsula, it was more common for trepanations to be performed in the frontal and parietal (top) regions of the skull. 

The risks of operating on the temporal region included "inherent challenges associated with accessing this area through the scalp," she said. This region in particular contains numerous blood vessels and muscles that are vulnerable and could easily bleed out during surgery.

However, prehistoric trepanations using the scraping technique were far more successful — and safer — than drilling. Ancient surgeons generally did not damage the meninges or the brain, lowering the risk for potential post-surgical infections, she said, adding that using sterile instruments and plants with natural antibiotic properties could help curb any infection.  

Unfortunately, researchers aren't sure why the woman had the surgery in the first place. Even though her skeleton did show healed rib fractures and some dental caries, these afflictions were likely unrelated. 

"The high prevalence of traumatic injuries documented in the skeletons from Camino del Molino leads us not to rule out the possibility that the surgery may have been performed as a result of trauma," she said. The surgery could have eliminated any evidence of bruising or incisions, and damaged bone fragments may have been removed during the procedure.

For the first time, a patient received a whole new eye and a partial face in a groundbreaking transplant procedure.

The transplant recipient, a 46-year-old from Arkansas named Aaron James, had sustained a 7,200-volt electric shock while working as a high-voltage lineman on June 10, 2021.

"Most individuals don't survive that level of injury," Dr. Eduardo Rodriguez, the lead surgeon for James' transplant and director of NYU Langone's face transplant program, said in a news conference Thursday (Nov. 9). In the accident, a live wire touched James' face. He needed several reconstructive surgeries and ultimately lost his left eye, nose, lips, front teeth, left cheek and chin, as well as his left arm above the elbow.

Now, James is about five months out from his transplant procedure, which involved 140 medical providers at NYU Langone and took place over 21 hours on May 27 and May 28, 2023.

"From the time I woke up from a six-week coma, they were already talking about a possible chance of a face transplant," James said at the news conference.

Related: 'Reanimated' hearts can be successfully transplanted and could expand donor pool

The surgery allowed him to stop using breathing and feeding tubes, and he can taste, smell and eat solid foods again. He finally returned home to Arkansas in September and now travels to New York monthly for monitoring. He also has ongoing physical, occupational and speech therapy.

Beyond these functional improvements, "I can't walk past a mirror without looking at it. It's making me stand up taller," James said of his new face. "Before the transplant, emotionally I was a little down, confidence level was a little low."

The NYU team first learned of James two months after the accident, when they started consulting his care team at a medical center in Texas. James' left eye needed removal due to severe pain, so the NYU team advised the surgeons to snip his optic nerve as close to the eyeball as possible, to potentially allow for a whole-eye transplant, along with his planned face transplant.

But the eye transplant would come with risks. "The eye is an extension of the brain," Dr. Vaidehi Dedania, a retina specialist in NYU Langone's Department of Ophthalmology, said at the news conference. A transplant that plugs into the central nervous system introduces a risk of deadly infection and inflammation of the brain, Rodriguez said.

It wasn't clear at first that this transplanted eye would ever be able to see, but early tests suggest light-detecting cells at the back of his eye do, at least, respond to light.

"His retina is able to tell us that it's 'seeing' the light, which is quite remarkable," Dedania said. Scans suggest that this signal makes it to the visual cortex at the back of James' brain. However, James can't yet perceive those incoming signals, so it's still unknown if he'll ever have vision in that eye, Dedania said.

Related: What are eyes made of?

To help the eye to plug into James' optic nerve, the team also transplanted adult stem cells, which are unspecialized and can give rise to other types of cells. The goal for these cells, which were isolated from the donor's bone marrow, was to have them help repair James' snipped optic nerve, potentially restoring its function.

During the procedure, two surgical teams — one for the donor and one for the recipient — operated simultaneously in nearby rooms. The teams thoroughly rehearsed all the steps of the procedure and printed 3D "cutting guides," to precisely carve out the donor's bone and tissue so they would fit into the space on James' face — "just like a puzzle," Rodriguez said.

Between 9:14 a.m. on May 27 and 7:51 a.m. on May 28, the team transplanted the nose, left upper and lower eyelids, left eyebrow, and upper and lower lips, as well as the tissues below the right eye. They also transplanted the underlying skull, cheek, nasal and chin bone segments that went with those tissues, as well as the left eye and accompanying optic nerve.

Now, five months out, James takes immunosuppressive drugs daily and has not shown signs of rejection. He cannot yet lift his upper left eyelid to open his left eye, which is brown, while his right eye is light blue. However, he's now able to squint and tighten the muscles around the eye, and the eyelid is protecting the eye well enough that he now doesn't need an eyepatch, Rodriguez said.

At the news conference, James expressed great thanks to the NYU team, the donor and the donor's family, and to his wife and daughter.

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To save a man who needed a double-lung transplant but had a very complicated case, doctors relied on three key tools: antibiotics, an artificial lung and DD-size breast implants.

"I never imagined we'd be using DD breast implants to help bridge a patient to lung transplantation, but our team is known for taking on the most difficult cases and thinking outside the box to save lives," Dr. Ankit Bharat, chief of thoracic surgery and director of the Canning Thoracic Institute at Northwestern Medicine, said in a statement.

The transplant patient, a 34-year-old Missouri man named David "Davey" Bauer, had started smoking cigarettes at age 21. He smoked about a pack a day until switching to e-cigarettes, or vape pens, in 2014. In April of this year, he began experiencing shortness of breath and was diagnosed with the flu. He also developed a bacterial infection of the lungs that was resistant to antibiotic treatment.

Bauer was admitted to a St. Louis hospital and was placed on an ECMO (extracorporeal membrane oxygenation) machine, which does the work of the heart and lungs, but his condition worsened. That's when Northwestern received a call about Bauer needing a double-lung transplant.

Related: Creating 'universal' transplant organs: New study moves us one step closer.

"Davey's lungs were so heavily infected that they started to liquify," Dr. Rade Tomic, a pulmonologist and medical director of the Northwestern Medicine Canning Thoracic Institute Lung Transplant Program, said in the statement. "If you looked at his X-ray, there was nothing left — the lungs were completely filled with pus."

The Northwestern team determined that, for Bauer to survive the transplant, his infection would need to clear first. To make that happen, they'd need to remove his extensively infected lungs.

To deliver oxygen to the man's organs while his lungs were removed, the team jerry-rigged pieces of an ECMO machine to create channels that would keep oxygenated blood flowing to Bauer's heart and out to the rest of his body.

"I spent the whole night thinking about how I'm going to create these channels and do all these things," Bharat told CNN. But even with these artificial channels in place, the medical team still needed a way to physically support Bauer's heart, given that the lungs, which normally surround it in the chest cavity, would be removed. In the end, they decided breast implants were the best tools for the job.

"One of our plastic surgeons was very gracious to give us a rapid-fire course on the different types, shapes and sizes of breast implants, so we picked out a couple options and some of them were easier than others to mold inside Davey's chest, with the DD option being the best fit," Bharat said in the Northwestern statement. 

Bauer's infected lungs were removed on May 26, his name came up for new lungs on May 27, and the procedure was completed on May 28. 

"I honestly barely remember walking into the ER [in St. Louis]," Bauer told People in an exclusive report published Nov. 7. "Then I woke up out here in Chicago with new lungs." 

Bauer was discharged to rehabilitation therapy in late September after recovering in the intensive care unit for several months.

"I plan to get a t-shirt made that says 'DD Davey' on it and change all my gaming profiles," Bauer said in the Northwestern statement. "But in all seriousness, I'm so proud to be the first Northwestern Medicine patient to undergo this innovative procedure, and I hope this medical first paves the way for more critically ill patients to receive lung transplants in the near future."

Bauer's GoFundMe page details more of his story.

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A man got stitched up after being stabbed with a knife — but the next day, he learned that the nearly half-foot blade was still in his belly.

The man in Nepal had been stabbed in the upper-right abdomen during a fight, which he poorly remembered due to being drunk. After the stabbing, the 22-year-old was taken to a "local medical shop," where a health care worker apparently closed up his wound without checking if any part of it was still stuck in his belly and sent him on his way, according to a case report published Sept. 2 in the journal Cureus. 

A day later, the man went to the emergency department because he had mild, continuous pain in his lower-left belly. At first glance, the man didn't have any swelling or symptoms that suggested gastrointestinal issues, like nausea, diarrhea or constipation, although he did have a sutured wound on his right side and tenderness above his left hip. Nor did he have signs of peritonitis, a condition in which the inner lining of the abdominal cavity becomes inflamed, which can happen after the tissue is injured in a stabbing. 

The doctors took an X-ray of the man's abdomen and found something "unusual and spectacular": The 5.9-inch (15 centimeters) blade from the attack was still floating in his belly and had "wandered" from one side to the other, yet none of the surrounding organs were severely injured, his doctors reported. 

Related: Teen had a shard of glass stuck in his face for a month without knowing it 

There was, however, a small, 0.4-inch-long (1 cm) cut on the front of his liver. Given that the liver is located in the upper-right abdomen, this injury was likely from the initial attack, the authors wrote. 

Stab injuries to the belly are common, but it is rare to see an object like a blade retained inside the body afterward, the authors noted. In particular, cases of knife blades remaining in the body are few and far between and have been more likely to be found in the chest than in the belly.

However, there have been reports of people eating sharp objects — such as clasp knives, blades and needles — that then somehow migrated through their bodies. 

Upon discovering the blade in the man in the new report, his doctors surgically removed the weapon. The patient made a full recovery and was released from the hospital five days later. 

It's unclear why the blade wasn't spotted by the man's initial health care provider, although the authors wrote that it may have been because "nobody suspected there could be any retained foreign body inside the abdominal cavity." They added that the most "wondrous part" of this case — the way the blade floated through the belly without damaging any organs — also remains a mystery. 

In an unusual case, a man's trip to the dentist indirectly triggered bleeding in his brain and led to him being diagnosed with a rare genetic disorder.

Half an hour after having two teeth extracted, the man in Australia, who was in his late 60s, suddenly felt dizzy and started throwing up. His vision was distorted to the point where he saw objects as if they'd been rotated 90 degrees counterclockwise.

Soon after, he went to the emergency department, where doctors determined that he had high blood pressure and his eyes were flickering to the left. He also walked unsteadily and kept falling to the right. A computed tomography (CT) scan revealed that the lower left half of his brain was bleeding — a condition known as intracerebral hemorrhage (ICH). 

ICH is a common form of stroke that can be triggered by many things, including abusing drugs like amphetamine, brain cancer, physical trauma and extremely low temperatures. For example, one woman with a history of high blood pressure developed it after taking part in the "Ice Bucket Challenge." 

Related: This man had a key lodged in his brain. Here's how he survived.

However, prior to the man's unusual case, there'd been only three other reports of people developing ICH after visiting the dentist. In the new case, published Aug. 2 in the journal BMJ Case Reports, doctors believe the man's ICH was likely triggered by a sudden increase in blood pressure following his dental procedure. 

There was, however, one more part of the puzzle to decipher. 

When probing the man's medical history, the doctors found that six weeks before his trip to the dentist, he'd been referred for a CT scan after his general practitioner suspected he had Parkinson's disease, a progressive disease that kills neurons and causes movement issues. At the time, doctors didn't find any issues with the blood vessels in the man's brain, but they did notice signs of white matter disease — a condition in which reduced blood flow causes damage to nerve fibers that pass information between different parts of the brain. The emergency department doctors then confirmed these signs of white matter disease with a magnetic resonance imaging (MRI) scan.

To pinpoint the cause of the white matter disease, the case report authors analyzed the man's DNA and found that he had a mutation in a gene called NOTCH3, which is associated with a rare, inherited disease that causes the walls of blood vessels to thicken, reducing the flow of blood through the brain. This condition is known as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). 

CADASIL is often very difficult to diagnose, given severe cases only affect 2 in every 100,000 people and the disease's common symptoms, such as vision problems, feeling weak and struggling to walk, can often resemble other neurological conditions, such as multiple sclerosis. 

ICH was originally thought to be a rare complication of CADASIL, the case report authors noted. However, recent research suggests it may be a more common complication than previously thought. Whether or not CADASIL and ICH are often linked, the case report authors flagged that this is the first time ICH has been reported in a patient with CADASIL following a dental procedure. 

Following the man's emergency department visit, doctors prescribed him medication to treat his high blood pressure, and three months later, he reported that his symptom of unsteadiness had improved and his vision had returned to normal. He has since been put on a long-term course of aspirin to improve the blood flow in his brain and help prevent further strokes. 

A new gene therapy that "resets" the brain's reward system could help treat alcohol use disorder, a new study in monkeys suggests. 

In monkeys who tend to drink heavily when provided lots of alcohol, surgically injecting a gene therapy into the brain increased the production of the so-called feel-good hormone dopamine, the study showed. This, in turn, dramatically reduced the primates' alcohol consumption, the effects of which were sustained over a year. 

If safe and effective in humans, the therapy could provide a "one-time" treatment for alcohol use disorder (AUD), a medical condition in which patients can't stop or control their drinking despite it negatively impacting their daily life. Excessive drinking causes 140,000 deaths a year in the U.S., and although AUD is one of the most common psychiatric disorders, only three drugs for it have been approved by the U.S. Food and Drug Administration (FDA). 

None directly target the underlying brain changes seen with sustained heavy drinking. 

Related: What does alcohol do to the body?

Alcohol boosts the brain's production of dopamine, which leads to feelings of relaxation and improved mood. However, in AUD, the brain adapts by producing less dopamine on its own, meaning people need to drink more to achieve the same positive effects.  

That's also true in monkeys that drink heavily, even during periods when they aren't consuming any alcohol, study lead author Kathleen Grant, a professor of behavioral neuroscience at Oregon Health & Science University, told Live Science.  

In the new study, published Monday (Aug. 14) in the journal Nature Medicine, Grant's team injected a genetically modified virus into the ventral tegmental area — a region in the brain involved in reward processing — of four monkeys as part of a surgical procedure. Those monkeys had been given access to increasingly higher amounts of ethanol dissolved in water over several months to the point where their consumption levels simulated chronic alcohol binge drinking in humans. 

Using a similar approach to what has already been used to treat Parkinson's disease and a rare genetic disorder known as aromatic L-amino acid decarboxylase deficiency, the harmless virus carried a gene that encodes the protein glial cell line-derived neurotrophic factor (GDNF), which helps preserve and regrow neurons. By putting the GDNF gene into cells that make dopamine, the team assumed it would spur them to produce normal levels of the chemical. 

The monkeys reduced their alcohol consumption by more than 90% compared with controls, and their dopamine levels were restored to "normal levels" for at least a year after treatment, roughly equivalent to nine to 12 years in human time, Grant said. Because relapse is such an "integral part of the cycle" of AUD, getting back to levels the animals had before they started drinking heavily is crucial, she emphasized. 

Andrew Mcquillin, a professor of molecular psychiatry at University College London who was not involved in the research, told Live Science in an email that the long-term side effects of this treatment are still unclear. Although brain surgery is "generally well-tolerated" in humans, he said it "seems a somewhat invasive approach for all but the most severe cases of alcohol use disorder."

Grant also urged caution in over-generalizing the findings. "This is only proof-of-principle that it is possible to reverse this behavior in people with drinking disorders that are resistant to all other treatments," she said. "This would not be your first line of treatment, [it] would be appropriate only for very severe cases of alcohol use disorder."

Mcquillin added that future studies will be needed to test the acceptability of this treatment for substance use disorders. The findings could, however, open doors for other treatment options. 

"There is also the possibility that new or existing small molecules that mimic the therapeutic mechanism in this study may represent new treatment targets for substance use disorders," he said.

Freedom. Hot dogs. Amputations. It's July Fourth in America, and U.S. hospital visits are about to skyrocket like so many Roman candles. Between 2000 and 2010, U.S. American emergency rooms treated an estimated 97,500 patients for fireworks-related injuries, ranging from burns to blindness to the total loss of fingers and forearms. It's "an annual trail of disaster following the glorious [holiday]," as one doctor put it way back in 1910 — and, as long as people keep blowing things up, it's here to stay. In the spirit of freedom and science, here are some of the strangest fireworks injuries ever recorded.

Rare wound infection

In 2021, surgeons amputated a 56-year-old man's leg after he was injured in a firework explosion accident and his wounds became infected. The man sustained severe burn injuries to his face, right arm and right leg and presented "foreign objects in the scrotum, left medial thigh, and medial forearm," according to a report in Radiology Case Reports.

In the first documented case of its kind, the patient's wounds became infected with Vibrio mimicus — a pathogen related to the bacteria that cause cholera (V. cholerae) that thrives in marine or brackish waters and can cause gastroenteritis when ingested in seafood. V. mimicus can also spread through fresh water, which is how physicians think the patient was infected. "The patient's infection was likely acquired at the burn site due to contamination of burn with stream water," they wrote.

Burn wound infections are known to increase fatality rates, according to the report.

Physicians deemed the patient's right leg unsalvageable and amputated it above the knee. The man later received a replacement prosthetic and made a "full recovery," according to the report.

Take it on the chin

A woman in her early 30s suffered a "devastating and uncommon injury" after she tripped while lighting a large, professional-level shell firework earlier this year. As she stumbled, the rocket hit the woman directly in the chin and detonated, blasting off her lower lip, fracturing her jawbone and causing "massive trauma" to her lower face.

Surgeons cleaned the wounds and removed shell fragments before they reconstructed the patient's jaw, chin and lips using skin from her forearms, according to a case report published in 2023 in the journal ePlasty.

Two months after the reconstructive surgery, doctors reported "satisfactory aesthetic outcomes, oral competence and speech," even though they did not manage to re-animate or innervate the lower lip. They noted, however, that the patient "did continue to experience such challenges as drooling while eating."

Splayed hand

Hands and fingers are at higher risk than any other body part in firework accidents. In 2019, surgeons recorded the  case of a 30-year-old man who was holding a lit firework when it exploded, ripping his right hand to shreds. Pictures published in a BMJ Case Report show the patient's "splayed" and "degloved" hand (meaning the blast stripped the skin from his fingers), as well as several fractures and exposed bones.

The injury was so severe that physicians deemed the middle finger "unsalvageable" and amputated it. Six weeks later, the patient, who was a professional and right-handed carpenter, reported near-normal sensation in his remaining four fingers and, despite some stiffness, achieved "adequate function of the hand." However, doctors noted he might not be able to return to his former work.

Blasted eardrums

In 2017, a wedding guest was standing near a firework box when it unexpectedly ignited ahead of the planned display, bursting both the man's eardrums. The 30-year-old presented to the emergency department with multiple triangular holes in his tympanic membranes, which separate the outer ear from the middle ear. The man lost his hearing and experienced tinnitus — hearing ringing and other sounds that do not come from an outside source.

The shape of the perforations was characteristic of traumatic ear injuries, according to a case summary in the New England Journal of Medicine (NEJM), but doctors were able to patch them up. Three months after the incident, the patient's eardrums had healed, and he recovered his hearing. 

Foreign bodies in the cornea

In 2017, a 44-y­ear-old man was lighting a firework, when the rocket exploded in his face, throwing hot shrapnel into both of his eyes. According to a report in The New England Journal of Medicine, the man was "unable to perceive light in the right eye" and had the vision in his left eye reduced to 20/80 acuity by the time he checked into the emergency room. Surgeons removed multiple "foreign bodies" (shown in panel A) from both corneas. Still, the man's vision never returned in his right eye, and his left eye improved only to 20/40 acuity. Eye damage is a common result of high-velocity injuries. Always wear safety goggles when dealing with explosive materials.

A leg full of dynamite

It takes an especially calm medical team to deal with a patient whose leg could literally explode. That almost happened in 2017, when a man arrived at the San Antonio Military Medical Center with an unexploded firework lodged in his leg. The man had been trying to set off a mortar-style firecracker, when the rocket ignited and blasted straight into his leg. Upon arriving at the hospital, he was quickly quarantined from other patients, and an Explosive Ordnance Disposal team had to supervise his treatment. Thankfully, the firework was removed without incident.

Blunt-force trauma

Fireworks don't need to "pop" to do big damage. In 2017, a 25-year-old Indiana man was killed in Kentucky when a legal firework launched directly into his chest, striking him hard enough to stop his heart. The man died shortly after at the local hospital. "The preliminary cause of death is blunt force trauma," a coroner at the Henderson County Coroner's Office told IndyStar.com. "The type [of firework] is supposed to explode 100 feet [30 meters] in the air," he added. "They were lighting legal fireworks."

Nothing but his shoulders down

In one of the most gruesome instances of modern fireworks malfunctioning, a 41-year-old man in North Dakota was decapitated while setting off Independence Day rockets in 2011, NBC News reported. The man was lighting fireworks outside his mobile home, when a humungous bang caught his neighbor's attention. The neighbor watched as the man walked into the street to light another firecracker — and then disappeared in a terrible cloud of smoke. "Within 10 seconds of us talking to him, he lit it, and all we saw was a cloud of smoke, a bang," the neighbor told NBC News. "When I walked up to his body, it was nothing but his shoulders down."

Phosphorus poisoning

Because white phosphorus goes up in flames when its temperature reaches about 86 degrees Fahrenheit (30 degrees Celsius), the 15th element is a common ingredient in things that go boom. These include match heads, Molotov cocktails and — you guessed it — fireworks. In the 1940s, the NEJM reported that several children had died from "acute phosphorus poisoning" after eating fireworks — "especially the so-called 'spit devil' variety," the NEJM reported. Remember: Phosphorus is toxic, and there are much better things to eat on Independence Day than fireworks.

Hands off

It's not unusual for people to lose fingers or entire hands when fireworks explode too close, too soon. To gain a brand-new hand out of the incident is a bit more remarkable. In 2000, a 38-year-old man received a successful hand transplant after losing his dominant left hand in a fireworks-lighting accident 13 years earlier, the NEJM reported. The graft healed well, and the transplant, sourced from a deceased 58-year-old donor, proved far more useful than a prosthesis. "At one year, the patient could perform many functional activities with his left hand that he had not been able to perform with his prosthesis, such as throwing a baseball, turning the pages of a newspaper, writing, and tying his shoelaces," the NEJM reported.

Patriotic tetanus

Tetanus, or lockjaw, occurs when Clostridium tetani bacteria infect the body, causing painful muscle contractions (particularly in the jaw). These bacteria are common in soil but can be thrown into the air as infectious spores if that soil is disturbed — say, by exploding fireworks.

Thus, in the late-19th century, tetanus cases spiked every year around Independence Day, when fireworks and celebratory gunshots blasted chunks of C. tetani-harboring soil all over bystanders' bodies. According to the American Medical Association, this so-called "patriotic tetanus" killed more than 400 people in 1903 and was likely responsible for two-thirds of all explosive-related deaths from 1903 to 1909. Thankfully, a tetanus antitoxin became available in 1900, and the world's first tetanus vaccine was introduced in 1924. In 2015, fewer than 10 fatal cases of tetanus were reported in the U.S.; however, tens of thousands of people still die of tetanus annually in less-developed nations.

Blew the house to atoms

Fireworks were temporarily outlawed in England in the late 1600s, but that didn't stop people from making them — it just stopped people from making them safely. Case in point: In 1810, a fireworks maker and her child assistant were readying rockets for King George III's golden jubilee, when 200 barrels of gunpowder ignited and "blew the house, and another adjoining, to atoms," according to "Pyrotechnics: The History and Art of Firework Making" (University of Michigan Library, 1922).

Blown to a considerable height

Fireworks factory explosions were a widespread problem in the 18th and 19th centuries, Brock wrote. Tragically, children were often the victims. In 1821, a child employed by a fireworks maker set a rocket by the fire to cool and nearly blew up the neighborhood. (He barely escaped "with his jacket on fire," a local reported.) Later, in 1825, two boys in a Whitechapel, London fireworks factory "were blown to a considerable height and were much injured" while ramming gunpowder into pyrotechnic rockets, according to a village bulletin. The Gunpowder Act of 1860 restored some semblance of regulation to the clearly explosive industry.