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By Max Kozlov A black and gold fork, knife and spoon lay on a pale blue plate over a white background in harsh sunlight Some of the health benefits of fasting kick in when food consumption resumes, animal experiments show.Credit: Getty Breaking a fast carries more health benefits than the fasting itself, a study in mice shows1. After mice had abstained from food, stem cells surged to repair damage in their intestines — but only when the mice were tucking into their chow again, the study found. But this activation of stem cells came at a price: mice were more likely to develop precancerous polyps in their intestines if they incurred a cancer-causing genetic change during the post-fasting period than if they hadn’t fasted at all. These results, published in Nature on 21 August, show that “regeneration isn’t cost-free”, says Emmanuelle Passegué, a stem-cell biologist at Columbia University Irving Medical Center in New York City, who wasn’t involved in the study. “There is a dark side that is important to consider.” Fast way to health Researchers have been investigating the potential health benefits of fasting for decades, and there is evidence that the practice can help to delay certain diseases and lengthen lifespan in rodents. But the underlying biological mechanisms behind these benefits have been a mystery. In 2018, Ömer Yilmaz, a stem-cell biologist at the Massachusetts Institute of Technology in Cambridge, and his colleagues found that stem cells are likely to be implicated. During fasting, these cells begin burning fats rather than carbohydrates as an energy source, leading to a boost in their ability to repair damage to the intestines in mice2. © 2024 Springer Nature Limited

Keyword: Obesity
Link ID: 29448 - Posted: 08.22.2024

By Pam Belluck When Shawn Connolly was diagnosed with Parkinson’s disease nine years ago, he was a 39-year-old daredevil on a skateboard, flipping and leaping from walls, benches and dumpsters through the streets of San Francisco. He appeared in videos and magazines, and had sponsorships from skateboard makers and shops. But gradually, he began to notice that “things weren’t really working right” with his body. He found that his right hand was cupping, and he began cradling his arm to hold it in place. His balance and alignment started to seem off. Over time, he developed a common Parkinson’s pattern, fluctuating between periods of rapid involuntary movements like “I’ve got ants in my pants” and periods of calcified slowness when, he said, “I could barely move.” A couple of years ago, Mr. Connolly volunteered for an experiment that summoned his daring and determination in a different way. He became a participant in a study exploring an innovative approach to deep brain stimulation. In the study, which was published Monday in the journal Nature Medicine, researchers transformed deep brain stimulation — an established treatment for Parkinson’s — into a personalized therapy that tailored the amount of electrical stimulation to each patient’s individual symptoms. The researchers found that for Mr. Connolly and the three other participants, the individualized approach, called adaptive deep brain stimulation, cut in half the time they experienced their most bothersome symptom. Mr. Connolly, now 48 and still skateboarding as much as his symptoms allow, said he noticed the difference “instantly.” He said the personalization gave him longer stretches of “feeling good and having that get-up-and-go.” © 2024 The New York Times Company

Keyword: Parkinsons
Link ID: 29447 - Posted: 08.21.2024

By Michael Eisenstein An analysis of almost 50,000 brain scans1 has revealed five distinct patterns of brain atrophy associated with ageing and neurodegenerative disease. The analysis has also linked the patterns to lifestyle factors such as smoking and alcohol consumption, as well as to genetic and blood-based markers associated with health status and disease risk. The work is a “methodological tour de force” that could greatly advance researchers’ understanding of ageing, says Andrei Irimia, a gerontologist at the University of Southern California in Los Angeles, who was not involved in the work. “Prior to this study, we knew that brain anatomy changes with ageing and disease. But our ability to grasp this complex interaction was far more modest.” The study was published on 15 August in Nature Medicine. Ageing can induce not only grey hair, but also changes in brain anatomy that are visible on magnetic resonance imaging (MRI) scans, with some areas shrivelling or undergoing structural alterations over time. But these transformations are subtle. “The human eye is not able to perceive patterns of systematic brain changes” associated with this decline, says Christos Davatzikos, a biomedical-imaging specialist at the University of Pennsylvania in Philadelphia and an author of the paper. Previous studies have shown that machine-learning methods can extract the subtle fingerprints of ageing from MRI data. But these studies were often limited in scope and most included data from a relatively small number of people. © 2024 Springer Nature Limited

Keyword: Development of the Brain; Brain imaging
Link ID: 29446 - Posted: 08.21.2024

By Marla Broadfoot When doctors ask Sara Gehrig to describe her pain, she often says it is indescribable. Stabbing, burning, aching—those words frequently fail to depict sensations that have persisted for so long they are now a part of her, like her bones and skin. “My pain is like an extra limb that comes along with me every day.” Gehrig, a former yoga instructor and personal trainer who lives in Wisconsin, is 44 years old. At the age of 17 she discovered she had spinal stenosis, a narrowing of the spinal cord that puts pressure on the nerves there. She experienced bursts of excruciating pain in her back and buttocks and running down her legs. That pain has spread over the years, despite attempts to fend it off with physical therapy, anti-inflammatory injections and multiple surgeries. Over-the-counter medications such as ibuprofen (Advil) provide little relief. And she is allergic to the most potent painkillers—prescription opioids—which can induce violent vomiting. Today her agony typically hovers at a 7 out of 10 on the standard numerical scale used to rate pain, where 0 is no pain and 10 is the most severe imaginable. Occasionally her pain flares to a 9 or 10. At one point, before her doctor convinced her to take antidepressants, Gehrig struggled with thoughts of suicide. “For many with chronic pain, it’s always in their back pocket,” she says. “It’s not that we want to die. We want the pain to go away.” Gehrig says she would be willing to try another type of painkiller, but only if she knew it was safe. She keeps up with the latest research, so she was interested to hear earlier this year that Vertex Pharmaceuticals was testing a new drug that works differently than opioids and other pain medications. That drug, a pill called VX-548, blocks pain signals before they can reach the brain. It gums up sodium channels in peripheral nerve cells, and obstructed channels make it hard for those cells to transmit pain sensations. Because the drug acts only on the peripheral nerves, it does not carry the potential for addiction associated with opioids—oxycodone (OxyContin) and similar drugs exert their effects on the brain and spinal cord and thus can trigger the brain’s reward centers and an addiction cycle.

Keyword: Pain & Touch; Drug Abuse
Link ID: 29445 - Posted: 08.21.2024

Juliana Ki In the United States, it's estimated that about 7 million people are living with Alzheimer's disease and related dementias. But the number of people with a formal diagnosis is far less than that. Now, a new study suggests the likelihood of getting a formal diagnosis may depend on where a person lives. Researchers at the University of Michigan and Dartmouth College found that diagnosis rates vastly differ across the country and those different rates could not simply be explained by dementia risk factors, like if an area has more cases of hypertension, obesity and diabetes. The reasons behind the disparity aren't clear, but researchers speculate that stigma as well as access to primary care or behavioral neurological specialists may impact the odds of getting a formal diagnosis. Sponsor Message "We tell anecdotes about how hard it is to get a diagnosis and maybe it is harder in some places. It's not just your imagination. It actually is different from place to place," said Julie Bynum, the study's lead author and a geriatrician at the University of Michigan Medical School. Those differences may have potential consequences. That's because a formal diagnosis of Alzheimer's opens up access to treatments that may slow down the brain changes associated with the disease. Without that formal diagnosis, patients also would not be eligible for clinical trials or insurance coverage for certain medications. Even in cases of dementia where treatment is not an option, a diagnosis can also help in the planning for a patient's care. The findings, published last week in the journal Alzheimer's & Dementia, emerged from two main questions: What percent of older adults are being diagnosed with dementia across communities in the U.S.? And is the percent we see different from what we would expect? © 2024 npr

Keyword: Alzheimers
Link ID: 29444 - Posted: 08.21.2024

By Darren Incorvaia Imagine being a male firefly when suddenly the telltale flashing of a female catches your eye. Enthralled, you speed toward love’s embrace — only to fly headfirst into a spider’s web. That flashy female was in fact another male firefly, himself trapped in the web, and the spider may have manipulated his light beacon to lure you in. This high-stakes drama plays out nightly in the Jiangxia District of Wuhan, China. There, researchers have found that male fireflies caught in the webs of the orb-weaver spider Araneus ventricosus flash their light signals more like females do, which leads other males to get snagged in the same web. And weirdly, the spiders might be making them do this, almost like hunters blowing a duck call to attract prey. “The idea that a spider can manipulate the signaling of a prey species is very intriguing,” said Dinesh Rao, a spider biologist at the University of Veracruz in Mexico. “They show clearly that a trapped firefly in the web attracts more fireflies.” Dr. Rao was not involved in the research, but served as a peer reviewer of the paper published Monday in the journal Current Biology. Xinhua Fu, a zoologist at Huazhong Agricultural University in Wuhan, was in the field surveying firefly diversity when he first noticed that male fireflies seemed to end up ensnared in orb-weaver spider webs more often than females. Wondering if the spiders were somehow specifically attracting males, he teamed up with Daiqin Li and Shichang Zhang, animal behavior experts from nearby Hubei University, to get to the bottom of this sticky mystery. Working near paddy fields and ponds, the researchers observed the flashing of trapped male fireflies and saw that it more closely resembled that of females than of free-flying males. Trapped males flashed using only one of their two bioluminescent lantern organs, and they made one flash at a time rather than multiple flashes in quick succession, the same lighting signals females send when trying to attract males. © 2024 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 29443 - Posted: 08.21.2024

Julia Kollewe Oran Knowlson, a British teenager with a severe type of epilepsy called Lennox-Gastaut syndrome, became the first person in the world to trial a new brain implant last October, with phenomenal results – his daytime seizures were reduced by 80%. “It’s had a huge impact on his life and has prevented him from having the falls and injuring himself that he was having before,” says Martin Tisdall, a consultant paediatric neurosurgeon at Great Ormond Street Hospital (Gosh) in London, who implanted the device. “His mother was talking about how he’s had such a improvement in his quality of life, but also in his cognition: he’s more alert and more engaged.” Oran’s neurostimulator sits under the skull and sends constant electrical signals deep into his brain with the aim of blocking abnormal impulses that trigger seizures. The implant, called a Picostim and about the size of a mobile phone battery, is recharged via headphones and operates differently between day and night. The video player is currently playing an ad. You can skip the ad in 5 sec with a mouse or keyboard “The device has the ability to record from the brain, to measure brain activity, and that allows us to think about ways in which we could use that information to improve the efficacy of the stimulation that the kids are getting,” says Tisdall. “What we really want to do is to deliver this treatment on the NHS.” As part of a pilot, three more children with Lennox-Gastaut syndrome will be fitted with the implant in the coming weeks, followed by a full trial with 22 children early next year. If this goes well, the academic sponsors – Gosh and University College London – will apply for regulatory approval. Tim Denison – a professor of engineering science at Oxford University and co-founder and chief engineer of London-based Amber Therapeutics, which developed the implant with the university – hopes the device will be available on the NHS in four to five years’ time, and around the world. © 2024 Guardian News & Media Limite

Keyword: Robotics; Epilepsy
Link ID: 29442 - Posted: 08.19.2024

By Sara Talpos Nervous system disorders are among the leading causes of death and disability globally. Conditions such as paralysis and aphasia, which affects the ability to understand and produce language, can be devastating to patients and families. Significant investment has been put toward brain research, including the development of new technologies to treat some conditions, said Saskia Hendriks, a bioethicist at the U.S. National Institutes of Health. These technologies may very well improve lives, but they also raise a host of ethical issues. That’s in part because of the unique nature of the brain, said Hendriks. It’s “the seat of many functions that we think are really important to ourselves, like consciousness, thoughts, memories, emotions, perceptions, actions, perhaps identity.” Saskia Hendriks, a bioethicist at the U.S. National Institutes of Health, recently co-authored an essay on the emerging ethical questions in highly innovative brain research. In a June essay in The New England Journal of Medicine, Hendriks and a co-author, Christine Grady, outlined some of the thorny ethical questions related to brain research: What is the best way to protect the long-term interests of people who receive brain implants as part of a clinical trial? As technology gets better at decoding thoughts, how can researchers guard against violations of mental privacy? And what best way to prepare for the far-off possibility that consciousness may one day arise from work derived from human stem cells? Hendriks spoke about the essay in a Zoom interview. Our conversation has been edited for length and clarity.

Keyword: Robotics
Link ID: 29441 - Posted: 08.19.2024

By Charles Q. Choi Tangles of tau protein track with cognitive impairments in Alzheimer’s disease. But even though tau is expressed throughout the brain, it clumps mainly in specific regions, such as the cortex and hippocampus. Other areas, such as the cerebellum and brainstem, are largely spared. Why tau aggregates this way has remained a mystery, but the answer may have to do with a previously overlooked, oversized and naturally occurring variant of the protein called “big tau,” according to a preprint posted 31 July on bioRxiv. Most tau isoforms range from 352 to 441 amino acids in size, but big tau comprises 758 amino acids. This supersized version is significantly more abundant in the cerebellum and brainstem than in the cortex and hippocampus of mice—and it is much less likely to form abnormal clumps than its smaller counterparts, the preprint shows. “Big tau can resist several key pathological changes related to [Alzheimer’s disease],” wrote study investigator Dah-eun Chloe Chung, a postdoctoral researcher in Huda Zoghbi’s lab at Baylor College of Medicine, in a post on X about the work. (Zoghbi declined to comment for this article because she says the study is currently under review for potential publication, and Chung did not respond to email requests for comment.) Scientists identified big tau in the peripheral nervous system in the 1990s, and it is the predominant tau isoform there. But most research on tau since then “ignores the existence of big tau,” according to a 2020 review. “No one has bothered to study this protein in the context of neurodegeneration,” says Veera Rajagopal, a research scientist at Regeneron, who did not take part in the new work. “All tau-related research has been focused on the shorter isoforms that play a key role in the tauopathies like Alzheimer’s disease, frontotemporal dementia and so on. Now many will go after this big guy.” © 2024 Simons Foundation

Keyword: Alzheimers
Link ID: 29440 - Posted: 08.19.2024

Linda Geddes Imagine a world in which you could solve problems, create art or music or even improve your tennis serve in your sleep. If scientists working in the field of lucid dreams succeed, that world could become a reality sooner than we realise. Researchers are developing techniques that could enable more people to experience lucid dreams – a state of consciousness where a person is aware they are dreaming and can recognise their thoughts and emotions while doing so – and transfer the content of these dreams into their waking lives. They have shown in recent months that it is possible to transfer the rhythm of dream music, switch on a real-life kettle and control a virtual car on a computer screen from inside a lucid dream. “Sooner or later there will be methods or tools that will allow anybody to experience lucid dreams easily or relatively easily, we are searching for ways to connect these two worlds together,” said Michael Raduga, the founder and CEO of REMspace Inc, a sleep research company in Redwood City, California who led the studies. “Even for people who don’t think they are smart, their subconscious is enormous, and we hope to be able to transfer all of this information into reality.” The video player is currently playing an ad. Although not everyone can do it, roughly half of the population have experienced at least one lucid dream in their lifetimes and around a fifth experience them once a month or more. An international group of researchers published a paper in Current Biology several years ago that suggested it was possible to ask people questions, either vocally or using morse code delivered via flashing lights, while they were in a lucid dream – including basic mathematical calculations – and for the dreamers to answer using eye movements or by contracting facial muscles to convey yes/no or numerical answers. © 2024 Guardian News & Media Limited

Keyword: Sleep
Link ID: 29439 - Posted: 08.19.2024

By Paula Span Mary Peart, 67, a retired nurse in Manchester-by-the-Sea, Mass., began taking gabapentin a year and a half ago to reduce the pain and fatigue of fibromyalgia. The drug helps her climb stairs, walk her dog and take art lessons, she said. With it, “I have a life,” she said. “If I forget to take a dose, my pain comes right back.” Jane Dausch has a neurological condition called transverse myelitis and uses gabapentin as needed when her legs and feet ache. “It seems to be effective at calming down nerve pain,” said Ms. Dausch, 67, a retired physical therapist in North Kingstown, R.I. Amy Thomas, who owns three bookstores in the San Francisco Bay Area, takes gabapentin for rheumatoid arthritis. Along with yoga and physical therapy, “it’s probably contributing to it being easier for me to move around,” Ms. Thomas, 67, said. All three are taking the non-opioid pain drug for off-label uses. The only conditions for which gabapentin has been approved for adult use by the Food and Drug Administration are epileptic seizures, in 1993, and postherpetic neuralgia, the nerve pain that can linger after a bout of shingles, in 2002. But that has not stopped patients and health care providers from turning to gabapentin (whose brand names include Neurontin) for a startling array of other conditions, including sciatica, neuropathy from diabetes, lower back pain and post-surgery pain. Also: Agitation from dementia. Insomnia. Migraines. Itching. Bipolar disorder. Alcohol dependence. Evidence of effectiveness for these conditions is all over the map. The drug appears to provide relief for some patients with diabetic neuropathy but not with some other kinds of neuropathic pain. Several small studies indicate that gabapentin can reduce the itching associated with kidney failure. But the data for its effectiveness against low back pain or a number of psychiatric disorders are limited and show no meaningful impact. “It’s crazy how many indications it’s used for,” said Dr. Michael Steinman, a geriatrician at the University of California, San Francisco, and a co-director of the U.S. Deprescribing Research Network. “It’s become a we-don’t-know-what-else-to-do drug.” © 2024 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 29438 - Posted: 08.19.2024

By Ashley Andreou “I still don’t trust my parents’ ability to feed me,” confessed Sofia after I asked what she was most anxious about, nearing discharge after two months on an inpatient eating disorders unit where I worked as a psychiatry resident. The 14-year-old girl was brought to the pediatrician by her parents, worried about her eating. They learned that Sofia (whose name has been changed for her privacy) had lost 30 pounds over three months—she was eating only one piece of fruit a day in the weeks leading up to her admission. She could barely walk home from school, her menses ceased, her hair fell out in clumps, and her heart rate dangerously slowed. But Sofia was not the patient that people often envision with an eating disorder. Her family was Spanish-speaking and had emigrated from Peru. Her confession contained both her fears about losing control of her eating as well as real concern for her life after leaving the hospital. Her deeply caring family struggled with family sessions during her inpatient treatment, complicated by the need for interpreters, a prescribed inpatient diet that differed from the meals typically eaten at home, and a hesitancy to ask questions of the health care team. While Sofia was successfully restored to a healthy weight at discharge from the hospital, finding appropriate outpatient treatment presented yet another challenge. Family-based treatment is a standardized outpatient therapy, which aims to restore adolescent patients to a healthy weight with the support of their parents; the therapy consists of three phases where the parents begin with most of the feeding responsibility, and the patient gradually gains more autonomy as they become renourished. It is the gold standard for adolescent outpatient therapy. However, Medicaid did not fully cover most of these programs, and finding one with a Spanish-speaking therapist was even rarer. Despite a social worker’s efforts, Sofia was wait-listed for a family treatment program with a Spanish-speaking provider who offered sliding-scale payment. © 2024 SCIENTIFIC AMERICAN

Keyword: Anorexia & Bulimia
Link ID: 29437 - Posted: 08.19.2024

By Carl Zimmer When people suffer severe brain damage — as a result of car crashes, for example, or falls or aneurysms — they may slip into a coma for weeks, their eyes closed, their bodies unresponsive. Some recover, but others enter a mysterious state: eyes open, yet without clear signs of consciousness. Hundreds of thousands of such patients in the United States alone are diagnosed in a vegetative state or as minimally conscious. They may survive for decades without regaining a connection to the outside world. These patients pose an agonizing mystery both for their families and for the medical professionals who care for them. Even if they can’t communicate, might they still be aware? A large study published on Wednesday suggests that a quarter of them are. Teams of neurologists at six research centers asked 241 unresponsive patients to spend several minutes at a time doing complex cognitive tasks, such as imagining themselves playing tennis. Twenty-five percent of them responded with the same patterns of brain activity seen in healthy people, suggesting that they were able to think and were at least somewhat aware. Dr. Nicholas Schiff, a neurologist at Weill Cornell Medicine and an author of the study, said the study shows that up to 100,000 patients in the United States alone might have some level of consciousness despite their devastating injuries. The results should lead to more sophisticated exams of people with so-called disorders of consciousness, and to more research into how these patients might communicate with the outside world, he said: “It’s not OK to know this and to do nothing.” When people lose consciousness after a brain injury, neurologists traditionally diagnose them with a bedside exam. They may ask patients to say something, to look to their left or right, or to give a thumbs-up. © 2024 The New York Times Company

Keyword: Consciousness
Link ID: 29436 - Posted: 08.15.2024

By Erin Garcia de Jesús An appetite-stimulating protein can reverse anorexia in mice. Mice with lack of appetite and weight loss — symptoms similar to people with anorexia — that were genetically tweaked to secrete a protein called ACBP ate more food and weighed more than anorexic animals with an ACBP deficit, researchers report August 14 in Science Translational Medicine. The finding points to a potential treatment target for people with the eating disorder. “Anorexia is a whole brain and body illness” that is difficult to treat, says psychiatrist and neuroscientist Rachel Ross, who wasn’t involved with the new work. “One of the major challenges is that the brain of a person with anorexia is directly fighting against their body.” While the body screams for food, the brain prioritizes the need to restrict weight (SN: 7/26/13). Globally, around 1 percent of women and 0.2 percent of men develop the disorder. Roughly just a third of those people fully recover. Yet, no drugs are available; treatment typically involves medical care to stabilize weight and therapy to mend patients’ relationships with food. Some cancer patients can also develop a similar disorder called cancer cachexia, which comes from an impaired metabolism, that is similarly tough to treat (SN: 7/30/24). “Anything that has the potential to provide some sort of mechanism that would be useful for creating a new therapeutic is huge,” says Ross, of Albert Einstein College of Medicine and Montefiore Health System in New York City. And although there’s no guarantee the results will apply to people, the new findings suggest that ACBP, a protein that helps turn on parts of the brain that arouse appetite, may have that potential. © Society for Science & the Public 2000–2024.

Keyword: Obesity; Hormones & Behavior
Link ID: 29435 - Posted: 08.15.2024

By Greg Donahue In late 2018, after an otherwise-normal Christmas holiday, Laurie Beatty started acting strange. An 81-year-old retired contractor, he grew unnaturally quiet and began poring over old accounting logs from a construction business he sold decades earlier, convinced that he had been bilked in the deal. Listen to this article, read by Robert Petkoff Over the course of several days, Beatty slipped further into unreality. He told his wife the year was 1992 and wondered aloud why his hair had turned white. Then he started having seizures. His arms began to move in uncontrollable jerks and twitches. By the end of May, he was dead. Doctors at the Georges-L.-Dumont University Hospital Center in Moncton, the largest city in the province of New Brunswick, Canada, zeroed in on an exceedingly rare condition — Creutzfeldt-Jakob disease, caused by prions, misfolding proteins in the brain — as the most likely culprit. The doctors explained this to Beatty’s children, Tim and Jill, and said they would run additional tests to confirm the post-mortem diagnosis. Three months later, when the siblings returned to the office of their father’s neurologist, Dr. Alier Marrero, that’s what they were expecting to hear. Instead, Marrero told them that Laurie’s Creutzfeldt-Jakob test had come back negative. “We were all looking at one another,” Tim says, “because we were all very confused.” If Creutzfeldt-Jakob hadn’t killed their father, then what had? What Marrero said next was even more unsettling. “There’s something going on,” they recall him saying. “And I don’t know what it is.” It turned out that Laurie Beatty was just one of many local residents who had gone to Marrero’s office exhibiting similar, inexplicable symptoms of neurological decline — more than 20 in the previous four years. The first signs were often behavioral. One patient fell asleep for nearly 20 hours straight before a friend took her to the hospital; another found himself afraid to disturb the stranger who had sat down in his living room, only to realize hours later that the stranger was his wife. © 2024 The New York Times Company

Keyword: Alzheimers; Learning & Memory
Link ID: 29434 - Posted: 08.15.2024

By Sara Reardon Last week’s decision by the US Food and Drug Administration (FDA) to reject MDMA, also known as ecstasy, as a psychiatric treatment surprised many researchers. Lykos Therapeutics, the company that has been testing MDMA, plans to ask the FDA to reconsider the decision, but scientists are now wondering what the agency’s ruling will mean for other potential psychedelic therapies. In a press release posted on 9 August, Lykos, which is based in San Jose, California, said that the FDA had sent a letter requesting that the company undertake another large-scale trial of the drug in people with post-traumatic stress disorder (PTSD) and resubmit its application. “The FDA request for another study is deeply disappointing,” Lykos chief executive Amy Emerson said in the press release, adding that the company plans to work with the agency to “resolve scientific disagreements”. Conducting another study “would take several years”, she said, adding that Lykos has already addressed many of the FDA’s concerns. In an e-mail to Nature, Lykos declined to provide the complete letter detailing the agency’s specific concerns and directed the news team instead to its press release. Experts say that without access to the letter, it’s hard to determine why the FDA reached the decision it did. “We really are going off incomplete information,” says Mason Marks, who studies drug policy at Florida State University in Tallahassee, adding that he was “a little surprised” by the agency’s decision. Trial concerns But Marks points out that the FDA typically follows the advice of its independent advisory committees — and the one that evaluated MDMA in June overwhelmingly voted against approving the drug, citing problems with clinical trial design that the advisers felt made it difficult to determine the drug’s safety and efficacy. One concern was about the difficulty of conducting a true placebo-controlled study with a hallucinogen: around 90% of the participants in Lykos’s trials guessed correctly whether they had received the drug or a placebo, and the expectation that MDMA should have an effect might have coloured their perception of whether it treated their symptoms. © 2024 Springer Nature Limited

Keyword: Drug Abuse; Depression
Link ID: 29433 - Posted: 08.15.2024

By Sara Reardon Stress can make people feel sick, and bacteria in the gut might be to blame, according to a study1 in mice. The research suggests that a stressed brain directly shuts down specific glands in the gut, affecting gut bacteria and the body’s broader immune system. The study “is a technical tour de force”, says neuroscientist John Cryan at University College Cork in Ireland, who reviewed the study. Most work on the gut–brain connection has focused on how bacteria affect the brain, so Cryan welcomes research into how psychological states can exert ‘top-down’ control of bacteria. “It’s a really cool part of the puzzle”, he says. The research was published on 8 August in Cell. Researchers have long known that the gut and brain ‘talk’ to each other. Under stress, the brain spurs the release of hormones that can trigger gut conditions such as inflammatory bowel disease. And certain bacteria in the gut can release chemical signals that affect the brain and behaviour. Your brain could be controlling how sick you get — and how you recover But the neural communication pathways are less well understood. To find out more, neuroscientist Ivan de Araujo at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany, and his colleagues focused on small organs called Brunner’s glands that are found in the walls of the small intestine. Little is known about these glands, other than that they produce mucus and contain numerous neurons. De Araujo’s team found that removing the Brunner’s glands of mice made the animals more susceptible to infection. It also raised markers of inflammation, a flood of immune chemicals and cells that can damage tissues. The team saw a similar effect in humans: people who’d had tumours removed from the part of the gut containing Brunner’s glands had higher levels of white blood cells — a marker of inflammation — than people who’d had tumours removed from other areas. © 2024 Springer Nature Limited

Keyword: Stress; Neuroimmunology
Link ID: 29432 - Posted: 08.13.2024

By Andrew Jacobs The journal Psychopharmacology has retracted three papers about MDMA-assisted therapy based on what the publication said was unethical conduct at one of the study sites where the research took place. Several of the papers’ authors are affiliated with Lykos Therapeutics, the drug company whose application for MDMA-assisted therapy to treat post-traumatic stress disorder was rejected last week by the Food and Drug Administration. The company said the research in the retracted papers was not part of its application to the F.D.A. In declining to approve Lykos’s application, the agency cited concerns about missing data and problems with the way the company’s study was designed, according to a statement released by Lykos on Friday. The F.D.A. has asked Lykos to conduct an additional clinical trial of its MDMA-assisted therapy, which would have been the first psychedelic medicine to win approval by federal regulators. Lykos has said it would appeal the decision. The journal retraction was first reported by Stat, the health and medical news website. On Sunday, Lykos said that it disagreed with Psychopharmacology’s decision and that it would file an official complaint with the Committee on Publication Ethics, a nonprofit that sets guidelines for academic publications. “The articles remain scientifically sound and present important contributions to the study of potential treatments for PTSD,” the company said in the statement. The incident cited by Psychopharmacology has been well documented. © 2024 The New York Times Company

Keyword: Stress; Drug Abuse
Link ID: 29431 - Posted: 08.13.2024

By Sneha Khedkar About 10 years ago, when Michael Yartsev set up the NeuroBat Lab, he built a new windowless cave of sorts: a fully automated bat flight room. Equipped with cameras and other recording devices, the remote-controlled space has enabled his team to study the neuronal basis of navigation, acoustic and social behavior in Egyptian fruit bats without having any direct interaction with the animals. “In our lab, there’s never a human involved in the experiments,” says Yartsev, associate professor of bioengineering at the University of California, Berkeley. The impetus to create the space was clear. The setup, paired with wireless electrodes inserted in the bats’ hippocampus, has helped the team demonstrate, for example, that place cells encode a flying bat’s current, past and future locations. Also, a mountain of evidence suggests that the identity, sex and stress levels of human experimenters can influence the behavior of and brain circuit activity in other lab animals, such as mice and rats. Now Yartsev and his team have proved that “experimenter effects” hold true for bats, too, according to a new study published last month in Nature Neuroscience. The presence of human experimenters changed hippocampal neuronal activity in bats both at rest and during flight—and exerted an even stronger influence than another fruit bat, the study shows. The team expected that humans would influence neural activity, Yartsev says, “but we did not expect it to be so profound.” © 2024 Simons Foundation

Keyword: Attention; Hearing
Link ID: 29430 - Posted: 08.13.2024

Ari Daniel On a dark night in northern Belize in early May, Gliselle Marin stands in the middle of a patchy forest in the Lamanai Archaeological Reserve, about a two-hour drive from where she grew up. Every few minutes, she and her fellow researchers sweep their headlamps over the nets they’ve strung up to see if they’ve caught anything. Before long, a chirping leaf-nosed bat the color of hot cocoa is entangled. He’s small — about the size of a lemon. Marin works carefully and quickly to free him. “We’re trying to get the net off of him,” she says. “It’s kind of like a puzzle. I like to take the feet out first. And then I do one wing, then the head.” Within a minute, the tiny bat is out. Marin jots down some basic information about the bat and then places him inside a cloth bag for further study that night. All the tools Marin needs for this kind of delicate extraction — including an ordinary crochet hook, for the worst tangles — fit into a fanny pack that’s adorned with little printed bats. The scientist also sports bat earrings, as well as a tattoo of small bats flying up the nape of her neck. Marin is a biology PhD student at York University in Toronto, and she’s here with the “Bat-a-thon,” a group of 80-some bat researchers who converge on this part of Belize each year to study these winged mammals. Growing up, Marin’s family had bats roosting under their house. “But when I actually started working with them and realizing we have close to 80 species of bats,” she says, “I was like, ‘Okay, it’s kind of crazy that I’ve been in science my whole life and was never taught that we have this diversity of bats in Belize.’” Over time, she’s come to admire not just the cornucopia of species, but the spectacular array of abilities and behaviors of these adaptable little animals. Scientists, she says, have only scratched the surface when it comes to understanding these furry, flying mammals. © 2024 npr

Keyword: Hearing
Link ID: 29429 - Posted: 08.13.2024