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Philip Hoare Whales are extraordinarily sensuous creatures. Those blubbery bodies are highly sensitive, and sensitised. At social meetings, pods of sperm, humpback and right whales will roll around one another’s bodies for hours at a time. I’ve seen a group of right whales engaged in foreplay and penetration lasting an entire morning. I have also watched a male-female couple so blissfully conjoined that they appeared unbothered by our little fishing boat as they passed underneath it. And in what may sound like a career of cetacean voyeurism, I have also been caught up in a fast-moving superpod of dusky dolphins continually penetrating each other at speed, regardless of the gender of their partner. That’s why this week’s report of the first scientifically documented male-to-male sexual interactions between two humpback whales off the coast of Hawaii is not surprising. The remarkable image of a two-metre whale penis entering another male “leaves little room for discussion that there is a sexual component to such behaviour”, as one whale scientist, Jeroen Hoekendijk at the Wageningen Marine Research institute in the Netherlands, notes drily. In fact, one of the whales was ailing and there has been speculation that the encounter may not have been consensual or that the healthy whale was actually giving comfort to the other. Whatever the truth, such “flagrant” acts also expose many of our human presumptions about sexuality, gender and identity. Off the north-west Pacific coast of the US, male orcas often leave family pods to rub their erections against each other’s bellies. But females have also reportedly been seen engaging in sexual contact with one another, too. © 2024 Guardian News & Media Limited
Keyword: Sexual Behavior
Link ID: 29173 - Posted: 03.02.2024
By Erica Goode Authors don’t get to choose what’s going on in the world when their books are published. More than a few luckless writers ended up with a publication date of Sept. 11, 2001, or perhaps Nov. 8, 2016, the day Donald Trump was elected. But Charan Ranganath, the author of “Why We Remember: Unlocking Memory’s Power to Hold on to What Matters,”was more fortunate. His book went on sale last month, not long after the Department of Justice released a report describing President Joe Biden as an “elderly man with a poor memory” who, in interviews, was “struggling to remember events,” including the year that his son Beau died. BOOK REVIEW — “Why We Remember: Unlocking Memory’s Power to Hold on to What Matters,” by Charan Ranganath (Doubleday, 304 pages). The special counsel’s report immediately became a topic of intense discussion — disputed by the White House, seized on by many Republicans, analyzed by media commentators, and satirized by late-night television hosts. But for Ranganath, a psychologist and neuroscientist at the University of California, Davis, who for decades has been studying the workings of memory, the report’s release was a stroke of luck. His book, which dispels many widespread but wrongheaded assumptions about memory — including some to which that special counsel Robert K. Hur appears to subscribe — could easily have been written as a corrective response. If Ranganath has a central message, it is that we are far too concerned about forgetting. Memory does not work like a recording device, preserving everything we have heard, seen, said, and done. Not remembering names or exact dates; having no recollection of the details of a conversation; being unable to recall where you left your glasses or your keys; or watching movies you saw in the past as if you are seeing them for the first time — these are not the symptoms of a failing brain.
Keyword: Learning & Memory
Link ID: 29172 - Posted: 03.02.2024
By Pam Belluck Long Covid may lead to measurable cognitive decline, especially in the ability to remember, reason and plan, a large new study suggests. Cognitive testing of nearly 113,000 people in England found that those with persistent post-Covid symptoms scored the equivalent of 6 I.Q. points lower than people who had never been infected with the coronavirus, according to the study, published Wednesday in The New England Journal of Medicine. People who had been infected and no longer had symptoms also scored slightly lower than people who had never been infected, by the equivalent of 3 I.Q. points, even if they were ill for only a short time. The differences in cognitive scores were relatively small, and neurological experts cautioned that the results did not imply that being infected with the coronavirus or developing long Covid caused profound deficits in thinking and function. But the experts said the findings are important because they provide numerical evidence for the brain fog, focus and memory problems that afflict many people with long Covid. “These emerging and coalescing findings are generally highlighting that yes, there is cognitive impairment in long Covid survivors — it’s a real phenomenon,” said James C. Jackson, a neuropsychologist at Vanderbilt Medical Center, who was not involved in the study. He and other experts noted that the results were consistent with smaller studies that have found signals of cognitive impairment. The new study also found reasons for optimism, suggesting that if people’s long Covid symptoms ease, the related cognitive impairment might, too: People who had experienced long Covid symptoms for months and eventually recovered had cognitive scores similar to those who had experienced a quick recovery, the study found. © 2024 The New York Times Company
Keyword: Attention; Learning & Memory
Link ID: 29171 - Posted: 02.29.2024
By Erin Garcia de Jesús A genetic parasite may have robbed humans and other apes of their tails. Around 25 million years ago, this parasite, a small stretch of repetitive DNA called an Alu element, ended up in a gene important for tail development, researchers report in the Feb. 29 Nature. The single insertion altered the gene Tbxt in a way that seems to have sparked one of the defining differences between monkeys and apes: Monkeys have tails, apes don’t. “It was like lightning struck once,” says Jef Boeke, a geneticist at New York University Langone Health, and ape behinds ultimately became bare. The genetic tweak may also give insight into why some babies are born with spinal cord defects such as spina bifida, when the tube that holds the cord doesn’t close all the way (SN: 12/6/16). Alu elements are part of a group of genetic parasites known as transposons or jumping genes that can hop across genetic instruction books, inserting themselves into their hosts’ DNA (SN: 5/16/17). Sometimes, when the gene slips itself into a piece of DNA that is passed down to offspring, these insertions become permanent parts of our genetic code. Transposons, including more than 1 million Alu elements, are found throughout our genome, says geneticist and systems biologist Bo Xia of the Broad Institute in Cambridge, Mass. Researchers once thought of transposons as genetic garbage, but some have central roles in evolution. Without transposons, the placenta, immune system and insulation around nerve fibers may not exist (SN: 2/16/24). And humans might still have tails. To find out how apes lost their tails, Xia, then at NYU Langone Health, Boeke and colleagues analyzed 140 genes involved in vertebrate tail development. © Society for Science & the Public 2000–2024.
Keyword: Evolution; Epigenetics
Link ID: 29170 - Posted: 02.29.2024
By Anthony Ham What is the meaning of a cat’s meow that grows louder and louder? Or your pet’s sudden flip from softly purring as you stroke its back to biting your hand? It turns out these misunderstood moments with your cat may be more common than not. A new study by French researchers, published last month in the journal Applied Animal Behaviour Science, found that people were significantly worse at reading the cues of an unhappy cat (nearly one third got it wrong) than those of a contented cat (closer to 10 percent). The study also suggested that a cat’s meows and other vocalizations are greatly misinterpreted and that people should consider both vocal and visual cues to try to determine what’s going on with their pets. The researchers drew these findings from the answers of 630 online participants; respondents were volunteers recruited through advertisements on social media. Each watched 24 videos of differing cat behaviors. One third depicted only vocal communication, another third just visual cues, and the remainder involved both. “Some studies have focused on how humans understand cat vocalizations,” said Charlotte de Mouzon, lead author of the study and a cat behavior expert at the Université Paris Nanterre. “Other studies studied how people understand cats’ visual cues. But studying both has never before been studied in human-cat communication.” Cats display a wide range of visual signals: tails swishing side to side, or raised high in the air; rubbing and curling around our legs; crouching; flattening ears or widening eyes. Their vocals can range from seductive to threatening: meowing, purring, growling, hissing and caterwauling. At last count, kittens were known to use nine different forms of vocalization, while adult cats uttered 16. That we could better understand what a cat wants by using visual and vocal cues may seem obvious. But we know far less than we think we do. © 2024 The New York Times Compan
Keyword: Animal Communication; Evolution
Link ID: 29169 - Posted: 02.29.2024
By Benjamin Ryan People who frequently smoke marijuana have a higher risk of heart attack and stroke, according to a study published on Wednesday. The article, published in The Journal of the American Heart Association, is an analysis of responses to the U.S. government’s annual survey on behavioral risk from 2016 to 2020. The respondents answered health questions, including reporting their own health problems related to heart disease. About 4 percent of the respondents reported daily marijuana use, which the researchers suggested raised the chance of a heart attack by 25 percent and of a stroke by 42 percent. Among those who never smoked tobacco, daily use was tied to a 49 percent higher risk of heart attack and a more than doubled risk of stroke, the study indicated. About three-quarters of the respondents said that smoking was their main method of using weed. The other quarter consumed it by vaping, through edibles or drinking it. “Cannabis smoke releases the same toxins and particulate matter that tobacco does,” said the study’s first author, Abra M. Jeffers, a data analyst at Massachusetts General Hospital in Boston. She conducted the analysis during her post-doctoral fellowship at the University of California, San Francisco. The study is merely observational in its review of survey responses; it does not provide conclusive evidence that regular marijuana use causes heart disease. Even so, researchers and experts said they were concerned about its implications, especially as cannabis use has increased in recent years. Thirty-eight states have legalized medical use of marijuana, and 24 have begun allowing recreational use. © 2024 The New York Times Company
Keyword: Drug Abuse
Link ID: 29168 - Posted: 02.29.2024
By Saima Sidik Eye diseases long thought to be purely genetic might be caused in part by bacteria that escape the gut and travel to the retina, research suggests1. Eyes are typically thought to be protected by a layer of tissue that bacteria can’t penetrate, so the results are “unexpected”, says Martin Kriegel, a microbiome researcher at the University of Münster in Germany, who was not involved in the work. “It’s going to be a big paradigm shift,” he adds. The study was published on 26 February in Cell. Inherited retinal diseases, such as retinitis pigmentosa, affect about 5.5 million people worldwide. Mutations in the gene Crumbs homolog 1 (CRB1) are a leading cause of these conditions, some of which cause blindness. Previous work2 suggested that bacteria are not as rare in the eyes as ophthalmologists had previously thought, leading the study’s authors to wonder whether bacteria cause retinal disease, says co-author Richard Lee, an ophthalmologist then at the University College London. CRB1 mutations weaken linkages between cells lining the colon in addition to their long-observed role in weakening the protective barrier around the eye, Lee and his colleagues found. This motivated study co-author Lai Wei, an ophthalmologist at Guangzhou Medical University in China, to produce Crb1-mutant mice with depleted levels of bacteria. These mice did not show evidence of distorted cell layers in the retina, unlike their counterparts with typical gut flora. Furthermore, treating the mutant mice with antibiotics reduced the damage to their eyes, suggesting that people with CRB1 mutations could benefit from antibiotics or from anti-inflammatory drugs that reduce the effects of bacteria. “If this is a novel mechanism that is treatable, it will transform the lives of many families,” Lee says. © 2024 Springer Nature Limited
Keyword: Vision
Link ID: 29167 - Posted: 02.27.2024
Terry Gross When cognitive neuroscientist Charan Ranganath meets someone for the first time, he's often asked, "Why am I so forgetful?" But Ranganath says he's more interested in what we remember, rather than the things we forget. "We're not designed to carry tons and tons of junk with us. I don't know that anyone would want to remember every temporary password that they've ever had," he says. "I think what [the human brain is] designed for is to carry what we need and to deploy it rapidly when we need it." Ranganath directs the Dynamic Memory Lab at the University of California, Davis, where he's a professor of psychology and neuroscience. In the new book, Why We Remember, he writes about the fundamental mechanisms of memory — and why memories often change over time. Sponsor Message Ranganath recently wrote an op-ed for The New York Times in which he reflected on President Biden's memory gaffes — and the role that memory plays in the current election cycle. "I'm just not in the position to say anything about the specifics of [either Biden or Trump's] memory problems," he says. "This is really more of an issue of people understanding what happens with aging. And, one of the nice things about writing this editorial is I got a lot of feedback from people who felt personally relieved by this because they're worried about their own memories." I think it would be a good idea to have a comprehensive physical and mental health evaluation that's fairly transparent. We certainly have transparency or seek transparency about other things like a candidate's finances, for instance. And obviously health is a very important factor. And I think at the end of the day, we'll still be in a position of saying, "OK, what's enough? What's the line between healthy and unhealthy?" But I think it's important to do because yes, as we get older we do have memory problems. ... © 2024 npr
Keyword: Learning & Memory; Development of the Brain
Link ID: 29166 - Posted: 02.27.2024
NIH-funded study shows prenatal mental health support is effective for women living in low-resource settings. Results from a large clinical trial funded by the National Institutes of Health show that an intervention for anxiety provided to pregnant women living in Pakistan significantly reduced the likelihood of the women developing moderate-to-severe anxiety, depression, or both six weeks after birth. The unique intervention was administered by non-specialized providers who had the equivalent of a bachelor’s degree in psychology—but no clinical experience. The results suggest this intervention could be an effective way to prevent the development of postpartum mental health challenges in women living in low-resource settings. “In low resource settings, it can be challenging for women to access mental health care due to a global shortage of trained mental health specialists,” said Joshua A. Gordon, M.D., Ph.D., Director of the National Institute of Mental Health, part of NIH. “This study shows that non-specialists could help to fill this gap, providing care to more women during this critical period." Led by Pamela J. Surkan, Ph.D., Sc.D.(link is external), of Johns Hopkins Bloomberg School of Public Health, Baltimore, the study was conducted in the Punjab Province of Pakistan between April 2019 and January 2022. Pregnant women with symptoms of at least mild anxiety were randomly assigned to receive either routine pregnancy care or a cognitive behavioral therapy (CBT)-based intervention called Happy Mother-Healthy Baby. The researchers assessed the participants (380 women in the CBT group and 375 women in the routine care group) for anxiety and depression six weeks after the birth of their child.
Keyword: Depression; Sexual Behavior
Link ID: 29165 - Posted: 02.27.2024
Ayana Archie The monthly rate of antidepressants being dispensed to young people increased about 64% more quickly during the coronavirus pandemic, according to a study published Monday in the journal Pediatrics. Researchers used the IQVIA Longitudinal Prescription Database to examine a sample of about 221 million prescriptions written for millions of Americans between the ages 12 to 25, and from 2016 to 2022. Researchers additionally separated the data into before and after March 2020, when the pandemic started. The increase was prominent among young women and girls. The monthly rate increased about 130% faster among 12- to 17-year-old girls, and about 57% faster among young women between the ages of 18 and 25. The study hypothesizes this jump could be due to high rates of depression or anxiety, better access to health care, due to things such as telehealth, or people's reliance on prescriptions because of long waitlists for therapy during the pandemic. The dataset includes prescriptions dispensed from "retail, mail-order, and long-term care pharmacies in the United States," the study says, not exclusive health care systems, such as Kaiser Permanente. Conversely, during the pandemic, the monthly antidepressant dispensing rate decreased for boys between the ages of 12 to 17 and did not change for young men between 18 and 25. Though, data shows more male adolescents were sent to the emergency room for suspected suicide attempts in early 2021, compared to early 2019. Between 2019 and 2021, male high school students also reported constantly feeling sad or hopeless more often, according to the researchers. © 2024 npr
Keyword: Depression
Link ID: 29164 - Posted: 02.27.2024
By Liam Drew The first person to receive a brain-monitoring device from neurotechnology company Neuralink can control a computer cursor with their mind, Elon Musk, the firm’s founder, revealed this week. But researchers say that this is not a major feat — and they are concerned about the secrecy around the device’s safety and performance. The company is “only sharing the bits that they want us to know about”, says Sameer Sheth, a neurosurgeon specializing in implanted neurotechnology at Baylor College of Medicine in Houston, Texas. “There’s a lot of concern in the community about that.” Threads for thoughts Musk announced on 29 January that Neuralink had implanted a brain–computer interface (BCI) into a human for the first time. Neuralink, which is headquartered in Fremont, California, is the third company to start long-term trials in humans. Some implanted BCIs sit on the brain’s surface and record the average firing of populations of neurons, but Neuralink’s device, and at least two others, penetrates the brain to record the activity of individual neurons. Neuralink’s BCI contains 1,024 electrodes — many more than previous systems — arranged on innovative pliable threads. The company has also produced a surgical robot for inserting its device. But it has not confirmed whether that system was used for the first human implant. Details about the first recipient are also scarce, although Neuralink’s volunteer recruitment brochure says that people with quadriplegia stemming from certain conditions “may qualify”.
Keyword: Robotics; Brain imaging
Link ID: 29163 - Posted: 02.25.2024
By Annie Melchor When the first known flying dinosaurs took to the skies some 150 million years ago, the evolutionary leap relied on adaptations to their nervous system. The changes remained a mystery, though, because of the paucity of fossilized neural tissue. Now fresh clues have emerged from a study that started with the long-gone dinosaurs’ living kin: the common pigeon, Columba livia. Flight taps neural pathways involving the pigeon’s cerebellum, the new works shows, which prompted study investigator Amy Balanoff and her team to look specifically at that structure in digital brain “endocasts,” created by CT scanning fossilized dinosaur skulls. “The birds can help us look for certain things within these extinct animals,” says Balanoff, assistant professor of evolutionary biology at Johns Hopkins University. “Then these extinct animals can tell us about the evolutionary history leading up to living birds.” An analysis of the endocasts — from 10 dinosaur specimens dating to between 90 and 150 million years ago — revealed that the volume of the cerebellum expanded in birds’ closest relatives, but not in more distant ones. And at some point, the cerebellum began folding — instead of growing — to accommodate more neurons within a fixed cranial space, Balanoff says. The results suggest that the cerebellum was “flight-ready before flying,” says Crístian Gutiérrez-Ibáñez, an evolutionary biology research associate at the University of Alberta who was not involved in the study. “So the question is, why did dinosaurs get such a big cerebellum?” © 2024 Simons Foundation
Keyword: Evolution; Movement Disorders
Link ID: 29162 - Posted: 02.25.2024
Fen-Biao Gao Around 55 million people worldwide suffer from dementia such as Alzheimer’s disease. On Feb. 22, 2024, it was revealed that former talk show host Wendy Williams had been diagnosed with frontotemporal dementia, or FTD, a rare type of dementia that typically affects people ages 45 to 64. Bruce Willis is another celebrity who was diagnosed with the syndrome, according to his family. In contrast to Alzheimer’s, in which the major initial symptom is memory loss, FTD typically involves changes in behavior. The initial symptoms of FTD may include changes in personality, behavior and language production. For instance, some FTD patients exhibit inappropriate social behavior, impulsivity and loss of empathy. Others struggle to find words and to express themselves. This insidious disease can be especially hard for families and loved ones to deal with. There is no cure for FTD, and there are no effective treatments. Up to 40% of FTD cases have some family history, which means a genetic cause may run in the family. Since researchers identified the first genetic mutations that cause FTD in 1998, more than a dozen genes have been linked to the disease. These discoveries provide an entry point to determine the mechanisms that underlie the dysfunction of neurons and neural circuits in the brain and to use that knowledge to explore potential approaches to treatment. I am a researcher who studies the development of FTD and related disorders, including the motor neuron disease amyotrophic lateral sclerosis, or ALS. ALS, also known as Lou Gehrig’s disease, results in progressive muscle weakness and death. Uncovering the similarities in pathology and genetics between FTD and ALS could lead to new ways to treat both diseases. Genes contain the instructions cells use to make the proteins that carry out functions essential to life. Mutated genes can result in mutated proteins that lose their normal function or become toxic. © 2010–2024, The Conversation US, Inc.
Keyword: Alzheimers; ALS-Lou Gehrig's Disease
Link ID: 29161 - Posted: 02.25.2024
David Robson Scientific discoveries can emerge from the strangest places. In early 1900s France, the doctor Albert Calmette and the veterinarian Camille Guérin aimed to discover how bovine tuberculosis was transmitted. To do so, they first had to find a way of cultivating the bacteria. Sliced potatoes – cooked with ox bile and glycerine – proved to be the perfect medium. As the bacteria grew, however, Calmette and Guérin were surprised to find that each generation lost some of its virulence. Animals infected with the microbe (grown through many generations of their culture) no longer became sick but were protected from wild TB. In 1921, the pair tested this potential vaccine on their first human patient – a baby whose mother had just died of the disease. It worked, and the result was the Bacille Calmette-Guérin (BCG) vaccine that has saved millions of lives. A black and white image pf Camille Guérin and physician Albert Calmette side by side. French veterinarian Camille Guérin and physician Albert Calmette developed the BCG jab in 1921 using sliced potatoes cooked with ox bile and glycerine. Photograph: Musée Pasteur Calmette and Guérin could have never imagined that their research would inspire scientists investigating an entirely different kind of disease more than a century later. Yet that is exactly what is happening, with a string of intriguing studies suggesting that BCG can protect people from developing Alzheimer’s disease. If these preliminary results bear out in clinical trials, it could be one of the cheapest and most effective weapons in our fight against dementia. According to the World Health Organization, 55 million people now have dementia, with about 10 million new cases each year. Alzheimer’s disease is by far the most common form, accounting for about 60%-70% of cases. It is characterised by clumps of a protein called amyloid beta that accumulate within the brain, killing neurons and destroying the synaptic connections between the cells. © 2024 Guardian News & Media Limited
Keyword: Alzheimers; Neuroimmunology
Link ID: 29160 - Posted: 02.25.2024
By Miryam Naddaf Moving a prosthetic arm. Controlling a speaking avatar. Typing at speed. These are all things that people with paralysis have learnt to do using brain–computer interfaces (BCIs) — implanted devices that are powered by thought alone. These devices capture neural activity using dozens to hundreds of electrodes embedded in the brain. A decoder system analyses the signals and translates them into commands. Although the main impetus behind the work is to help restore functions to people with paralysis, the technology also gives researchers a unique way to explore how the human brain is organized, and with greater resolution than most other methods. Scientists have used these opportunities to learn some basic lessons about the brain. Results are overturning assumptions about brain anatomy, for example, revealing that regions often have much fuzzier boundaries and job descriptions than was thought. Such studies are also helping researchers to work out how BCIs themselves affect the brain and, crucially, how to improve the devices. “BCIs in humans have given us a chance to record single-neuron activity for a lot of brain areas that nobody’s ever really been able to do in this way,” says Frank Willett, a neuroscientist at Stanford University in California who is working on a BCI for speech. The devices also allow measurements over much longer time spans than classical tools do, says Edward Chang, a neurosurgeon at the University of California, San Francisco. “BCIs are really pushing the limits, being able to record over not just days, weeks, but months, years at a time,” he says. “So you can study things like learning, you can study things like plasticity, you can learn tasks that require much, much more time to understand.” © 2024 Springer Nature Limited
Keyword: Brain imaging; Robotics
Link ID: 29159 - Posted: 02.22.2024
Nicola Davis Science correspondent From forgetfulness to difficulties concentrating, many people who have long Covid experience “brain fog”. Now researchers say the symptom could be down to the blood-brain barrier becoming leaky. The barrier controls which substances or materials enter and exit the brain. “It’s all about regulating a balance of material in blood compared to brain,” said Prof Matthew Campbell, co-author of the research at Trinity College Dublin. “If that is off balance then it can drive changes in neural function and if this happens in brain regions that allow for memory consolidation/storage then it can wreak havoc.” Writing in the journal Nature Neuroscience, Campbell and colleagues report how they analysed serum and plasma samples from 76 patients who were hospitalised with Covid in March or April 2020, as well 25 people before the pandemic. Among other findings, the team discovered that samples from the 14 Covid patients who self-reported brain fog contained higher levels of a protein called S100β than those from Covid patients without this symptom, or people who had not had Covid. caskets at a funeral home This protein is produced by cells within the brain, and is not normally found in the blood, suggesting these patients had a breakdown of the blood-brain barrier. The researchers then recruited 10 people who had recovered from Covid and 22 people with long Covid – 11 of whom reported having brain fog. None had, at that point, received a Covid vaccine, or been hospitalised for Covid. These participants underwent an MRI scan in which a dye was administered intravenously. The results reveal long Covid patients with brain fog did indeed show signs of a leaky blood-brain barrier, but not those without this symptom, or who had recovered. © 2024 Guardian News & Media Limited
Keyword: Neuroimmunology
Link ID: 29158 - Posted: 02.22.2024
By Pam Belluck Jennifer Caldwell was active and energetic, working two jobs and taking care of her daughter and her parents, when she developed a bacterial infection that was followed by intense lightheadedness, fatigue and memory problems. That was nearly a decade ago, and she has since struggled with the condition known as myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS. Ms. Caldwell, 56, of Hillsborough, N.C., said she went from being able to ski, dance and work two jobs as a clinical research coordinator and a caterer to needing to stay in bed most of every day. “I haven’t been right since, and I haven’t worked a day since,” said Ms. Caldwell, whose symptoms include severe dizziness whenever her legs are not elevated. The condition has also “messed me up cognitively,” she said. “I can’t read something and comprehend it very well at all, I can’t remember new things. It’s kind of like being in a limbo state. That’s how I describe it, lost in limbo.” Seven years ago, the National Institutes of Health began a study of patients with ME/CFS, and Ms. Caldwell became one of 17 participants who engaged in a series of tests and evaluations of their blood, bodies and brains. Findings from the study, which was published on Wednesday in the journal Nature Communications, showed notable physiological differences in the immune system, cardio-respiratory function, gut microbiome and brain activity of the ME/CFS patients compared with a group of 21 healthy study participants. Medical experts said that even though the study was a snapshot of a small number of patients, it was valuable, partly because ME/CFS has long been dismissed or misdiagnosed. The findings confirm that “it’s biological, not psychological,” said Dr. Avindra Nath, the chief of infections of the nervous system at the National Institute of Neurological Disorders and Stroke, who led the study. © 2024 The New York Times Company
Keyword: Neuroimmunology; Depression
Link ID: 29157 - Posted: 02.22.2024
By Jackie Rocheleau Every day about 60,000 people have surgery under general anesthesia in the United States. Often casually compared to falling into a deep sleep, going under is in fact wildly different from your everyday nocturnal slumber. Not only does a person lose the ability to feel pain, form memories, or move—they can’t simply be nudged back into conscious awareness. But occasionally, people do wake unexpectedly—in about 1 out of every 1,000 to 2,000 surgeries, patients emerge from the fog of anesthesia into the harsh light of the operating room while still under the knife. One question that has dogged researchers over the past several decades is whether women are more likely to find themselves in these unfortunate circumstances. A number of recent studies, including a 2023 meta-analysis, suggest that the answer is yes. But the findings are controversial: Other studies have found no differences in waking frequency between the sexes and most of the studies were not designed specifically to identify sex differences. It’s also difficult to know whether other factors might have influenced the results: rates of metabolization of drugs by male and female bodies, as well as variation in kinds of surgeries and anesthetic regimens among study participants. No causal link had been established. Now, a new study published in the Proceedings of the National Academy of Sciences helps untangle some of the mystery. In a series of experiments in mice and in humans, the researchers found that females do wake more easily from anesthesia and that testosterone plays an important role in how quickly and deeply we go under, and how easily we wake up. “There seems to be something hardwired into the female brain that biases it more toward a state of wakefulness,” says University of Pennsylvania anesthesiologist Max Kelz, co-author of the study. © 2024 NautilusNext Inc., All rights reserved.
Keyword: Sexual Behavior; Sleep
Link ID: 29156 - Posted: 02.22.2024
By David Ovalle Keifer Geers was born with a hole in his diaphragm that led to painful surgeries in adulthood. Despite physical challenges that included deafness, Geers graduated from Texas A&M University with a degree in biomedical engineering. He hoped to one day create medical devices for disabled children and wounded veterans. On a spring day as Geers walked with his mother through an airport in Midland, Tex., he stumbled, then collapsed into a seizure, his face contorted in shock. Geers, 33, was pronounced dead at a hospital. His mother later found inside his suitcase several packages of powder kratom, an herbal product he consumed to manage pain from surgeries. Patricia Geers said she was stunned when an autopsy concluded that her son died from the toxic effects of kratom — levels in his blood were more than nine times what some experts believe can prove lethal. The death of Keifer Geers was hardly an isolated episode. A Washington Post review of federal and state statistics shows that medical examiners and coroners are increasingly blaming deaths on kratom — it was listed as contributing to or causing at least 4,100 deaths in 44 states and D.C. between 2020 and 2022. The vast majority of those cases involved other drugs in addition to kratom, which is made from the leaves of tropical trees. Still, the kratom-involved deaths account for a small fraction of the more than 300,000 U.S. overdose deaths recorded in those three years. Dozens of wrongful death lawsuits involving kratom have been filed nationwide — including by Geers’s mother, who in February sued a Nevada retailer. The suits illustrate increased scrutiny of deaths involving products made from kratom, which is banned in six states but remains widely available online and in vape and convenience stores despite health warnings from federal authorities.
Keyword: Drug Abuse
Link ID: 29155 - Posted: 02.22.2024
By Tina Hesman Saey One particular retrovirus — embedded in the DNA of jawed vertebrates — helps turn on production of a protein needed to insulate nerve fibers, researchers report February 15 in Cell. Such insulation, called myelin, may have helped make speedy thoughts and complex brains possible. The retrovirus trick was so handy, in fact, that it showed up many times in the evolution of vertebrates with jaws, the team found. Retroviruses — also known as jumping genes or retrotransposons — are RNA viruses that make DNA copies of themselves to embed in a host’s DNA. Scientists once thought of remnants of ancient viruses as genetic garbage, but that impression is changing, says neuroscientist Jason Shepherd, who was not involved in the study. “We’re finding more and more that these retrotransposons and retroviruses have influenced the evolution of life on the planet,” says Shepherd, of the University of Utah Spencer Fox Eccles School of Medicine in Salt Lake City. Remains of retroviruses were already known to have aided the evolution of the placenta, the immune system and other important milestones in human evolution (SN: 5/16/17). Now, they’re implicated in helping to produce myelin. Myelin is a coating of fat and protein that encases long nerve fibers known as axons. The coating works a bit like the insulation around an electrical wire: Nerves sheathed in myelin can send electrical signals faster than uninsulated nerves can. © Society for Science & the Public 2000–2024.