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Yongsoo Kim The brain plays an essential role in how people navigate the world by generating both thought and behavior. Despite being one of the most vital organs of life, it takes up only 2% of human body volume. How can something so small perform such complex tasks? Luckily, modern tools like brain mapping have allowed neuroscientists like me to answer this exact question. By mapping out how all the cell types in the brain are organized and examining how they communicate with one another, neuroscientists can better understand how brains normally work, and what happens when certain cell parts go missing or malfunction. The task of understanding the inner workings of the brain has fascinated both philosophers and scientists for centuries. Aristotle proposed that the brain is where spirit resides. Leonardo da Vinci drew anatomical depictions of the brain with wax embedding. And Santiago Ramón y Cajal, with his 1906 Nobel Prize-winning work on the cellular structure of the nervous system, made one of the first breakthroughs that led to modern neuroscience as we know it. Using a new way to visualize individual cells called Golgi staining, a method pioneered by Nobel co-winner Camillo Golgi, and microscopic examination of brain tissue, Cajal established the seminal neuron doctrine. This principle states that neurons, among the main types of brain cells, communicate with one another via the gaps between them called synapses. These findings launched a race to understand the cellular composition of the brain and how brain cells are connected to one another. Conversation US, Inc.

Keyword: Brain imaging
Link ID: 28085 - Posted: 11.20.2021

by Niko McCarty Growing numbers of autistic children are diagnosed with the condition before age 3, in the United States, and those diagnoses tend to precede the start of any interventions or developmental services, according to a new study based on parent surveys. Children traversing autism’s ‘diagnostic odyssey’ a decade ago were typically diagnosed years later, and only after they had begun receiving services. The analysis included data from 2,303 autistic children aged 2 to 17 years from the National Survey of Children’s Health, which asks parents questions about the children in their household. The selected participants, split into three groups based on their age, either had a plan for early intervention or had received special services to meet developmental needs. The oldest children, aged 12 to 17 at the time of the survey, had been diagnosed at about age 5 and a half years, on average. Their first intervention or developmental service occurred at around age 5. By contrast, the youngest cohort, aged 2 to 5, had been diagnosed at about age 2 and a half years and started their first intervention or developmental services at roughly the same age. The results are based on parent responses to a question — “How old was your child when a doctor or other health care provider first said they had autism?” — so the findings likely skew toward younger ages than if the researchers had used clinical diagnoses. Also, the study omitted children who did not already have a diagnosis, which might have pushed the average age older. Still, the findings suggest that the time between getting a diagnosis and accessing services is shrinking. © 2021 Simons Foundation

Keyword: Autism
Link ID: 28084 - Posted: 11.20.2021

Riluzole, a drug approved to treat amyotrophic lateral sclerosis (ALS), a disease affecting nerve cells controlling movement, could slow the gradual loss of a particular brain cell that occurs in Niemann-Pick disease type C1 (NPC1), a rare genetic disorder affecting children and adolescents, suggests a study in mice by scientists at the National Institutes of Health. The study was conducted by Forbes D. Porter, M.D., Ph.D., of NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), and colleagues in the National Human Genome Research Institute and National Institute of Arthritis and Musculoskeletal and Skin Disease. It appears in Molecular Genetics and Metabolism. The study was supported in part by a grant from the Ara Parseghian Medical Research Foundation. NPC1 results from an impaired ability to move cholesterol through cells, leading to difficulty controlling movements, liver and lung disease, impaired swallowing, intellectual decline and death. Much of the movement difficulties in NPC1 result from gradual loss of brain cells known as Purkinje neurons. The researchers found that mice with a form of NPC1 have a diminished ability to lower levels of glutamate — a brain chemical that stimulates neurons — after it has bound to a neuron’s surface. High levels of glutamate can be toxic to cells. The researchers believe the buildup of glutamate contributes to the brain cell loss seen in the disease. Riluzole blocks the release of glutamate and hence delays the progression of ALS in people.

Keyword: Movement Disorders
Link ID: 28083 - Posted: 11.20.2021

Andrew Gregory Health editor Drinking coffee or tea may be linked with a lower risk of stroke and dementia, according to the largest study of its kind. Strokes cause 10% of deaths globally, while dementia is one of the world’s biggest health challenges – 130 million are expected to be living with it by 2050. In the research, 365,000 people aged between 50 and 74 were followed for more than a decade. At the start the participants, who were involved in the UK Biobank study, self-reported how much coffee and tea they drank. Over the research period, 5,079 of them developed dementia and 10,053 went on to have at least one stroke. Researchers found that people who drank two to three cups of coffee or three to five cups of tea a day, or a combination of four to six cups of coffee and tea, had the lowest risk of stroke or dementia. Those who drank two to three cups of coffee and two to three cups of tea daily had a 32% lower risk of stroke. These people had a 28% lower risk of dementia compared with those who did not drink tea or coffee. The research, by Yuan Zhang and colleagues from Tianjin Medical University, China, suggests drinking coffee alone or in combination with tea is also linked with lower risk of post-stroke dementia. Writing in the journal Plos Medicine, the authors said: “Our findings suggested that moderate consumption of coffee and tea separately or in combination were associated with lower risk of stroke and dementia.” © 2021 Guardian News & Media Limited

Keyword: Stroke; Drug Abuse
Link ID: 28082 - Posted: 11.20.2021

Sophie Fessl Catching some z’s repairs a day’s damage to neurons’ DNA, at least in zebrafish. While the fish are awake, DNA damage accumulates, which, through a buildup of the DNA repair protein Parp1, triggers sleep, according to a study published today (November 18) in Molecular Cell. The study is “pivotal in providing evidence regarding sleep and its role in DNA damage and repair,” writes anesthesiologist Siu Wai Choi of the University of Hong Kong in an email to The Scientist. Choi led an earlier study that established a link between sleep deprivation and DNA damage in doctors but was not involved in the current research. Cells routinely face stress, such as exposure to radiation, that can leave their DNA damaged. Cells therefore have an arsenal of repair proteins to mend the DNA or, if it’s irreparable, trigger cell death. Neuroscientist Lior Appelbaum and his team at Bar-Ilan University in Israel had previously found that DNA damage increases during the day and decreases during the night, suggesting that sleep could help repair this damage. In the new study, they investigated whether DNA damage is the reason why zebrafish—and, by extension, perhaps other animals—sleep. When postdoc David Zada and other authors induced DNA damage in the neurons of zebrafish larvae by inducing neuronal activity or using UV radiation, the fish slept longer. “It makes the fish tired,” says Appelbaum. © 1986–2021 The Scientist.

Keyword: Sleep; Genes & Behavior
Link ID: 28081 - Posted: 11.20.2021

Anil Ananthaswamy How our brain, a three-pound mass of tissue encased within a bony skull, creates perceptions from sensations is a long-standing mystery. Abundant evidence and decades of sustained research suggest that the brain cannot simply be assembling sensory information, as though it were putting together a jigsaw puzzle, to perceive its surroundings. This is borne out by the fact that the brain can construct a scene based on the light entering our eyes, even when the incoming information is noisy and ambiguous. Consequently, many neuroscientists are pivoting to a view of the brain as a “prediction machine.” Through predictive processing, the brain uses its prior knowledge of the world to make inferences or generate hypotheses about the causes of incoming sensory information. Those hypotheses — and not the sensory inputs themselves — give rise to perceptions in our mind’s eye. The more ambiguous the input, the greater the reliance on prior knowledge. “The beauty of the predictive processing framework [is] that it has a really large — sometimes critics might say too large — capacity to explain a lot of different phenomena in many different systems,” said Floris de Lange, a neuroscientist at the Predictive Brain Lab of Radboud University in the Netherlands. However, the growing neuroscientific evidence for this idea has been mainly circumstantial and is open to alternative explanations. “If you look into cognitive neuroscience and neuro-imaging in humans, [there’s] a lot of evidence — but super-implicit, indirect evidence,” said Tim Kietzmann of Radboud University, whose research lies in the interdisciplinary area of machine learning and neuroscience. All Rights Reserved © 2021

Keyword: Attention; Vision
Link ID: 28080 - Posted: 11.17.2021

David Robson Michelle Carr is frequently plagued by tidal waves in her dreams. What should be a terrifying nightmare, however, can quickly turn into a whimsical adventure – thanks to her ability to control her dreams. She can transform herself into a dolphin and swim into the water. Once, she transformed the wave itself, turning it into a giant snail with a huge shell. “It came right up to me – it was a really beautiful moment.” There’s a thriving online community of people who are now trying to learn how to lucid dream. (A single subreddit devoted to the phenomenon has more than 400,000 members.) Many are simply looking for entertainment. “It’s just so exciting and unbelievable to be in a lucid dream and to witness your mind creating this completely vivid simulation,” says Carr, who is a sleep researcher at the University of Rochester in New York state. Others hope that exercising skills in their dreams will increase their real-life abilities. “A lot of elite athletes use lucid dreams to practise their sport.” And there are more profound reasons to exploit this sleep state, besides personal improvement. By identifying the brain activity that gives rise to the heightened awareness and sense of agency in lucid dreams, neuroscientists and psychologists hope to answer fundamental questions about the nature of human consciousness, including our apparently unique capacity for self-awareness. “More and more researchers, from many different fields, have started to incorporate lucid dreams in their research,” says Carr. This interest in lucid dreaming has been growing in fits and starts for more than a century. Despite his fascination with the interaction between the conscious and subconscious minds, Sigmund Freud barely mentioned lucid dreams in his writings. Instead, it was an English aristocrat and writer, Mary Arnold-Forster, who provided one of the earliest and most detailed descriptions in the English language in her book Studies in Dreams. © 2021 Guardian News & Media Limited

Keyword: Sleep; Consciousness
Link ID: 28079 - Posted: 11.17.2021

By Emily Willingham As with most decision points around pregnancy, cannabis use is a fraught subject. Researchers can’t assess it in randomized trials because dosing pregnant people with the psychoactive substance is unethical. The next best thing is studies with enough participants who use cannabis on their own, allowing for comparisons with those who do not. The findings of one such study, published on November 15 in the Proceedings of the National Academy of Sciences USA, highlight symptoms of increased anxiety, hyperactivity and aggression in children whose parents used cannabis during pregnancy. And its analysis of placental tissue points to changes in the activity of immunity-related genes. Today pregnant people “are being bombarded with a lot of ads to treat nausea and anxiety during pregnancy” with cannabis, says the paper’s senior author Yasmin Hurd, director of the Addiction Institute at Mount Sinai. “Our studies are about empowering them with knowledge and education so that they can make decisions.” The results are “very striking, very much a first,” says Daniele Piomelli, a professor and director of the Center for the Study of Cannabis at the University of California, Irvine, who was not involved in the work. Pregnancy studies in rodents and even in sheep, which have a placenta more like ours, have required cautious interpretations of findings that show effects on offspring behavior and function, he says. The new study is one of the first to tackle the question in people “in a systematic way,” Piomelli adds. © 2021 Scientific American

Keyword: ADHD; Drug Abuse
Link ID: 28078 - Posted: 11.17.2021

Asher Mullard When the US Food and Drug Administration (FDA) approved biotechnology firm Biogen’s drug for Alzheimer’s disease in June, regulators hoped to usher in a new era of treatment for the neurodegenerative condition. But the decision followed an independent advisory committee’s near-unanimous vote to reject the drug, called aducanumab — and instead divided the community. Some researchers think that the approval will bolster the development of drugs for treating brain disease, but others see it as a blemish on the FDA’s integrity and an obstacle to progress. Pharmaceutical company Eli Lilly in Indianapolis hopes that its antibody donanemab, which works in a similar way to aducanumab, will have a better reception. The firm plans to finish submitting its drug candidate for FDA approval in the next few months, paving the way for a decision in the second half of 2022. Meanwhile, Biogen, based in Cambridge, Massachusetts, and its partner Eisai, based in Tokyo, are racing to complete the submission of data for another competitor, lecanemab. The regulatory fate of these therapeutic hopefuls could foretell the future of Alzheimer’s and shape neurodegenerative drug development programmes for years. According to the ‘amyloid hypothesis’ of Alzheimer’s disease, the build-up of a protein called amyloid-β in the brain causes neurodegeneration. Aducanumab and its would-be competitors clear clumps of amyloid-β from the brain. But clinical trials have not meaningfully demonstrated that these therapeutics slow memory loss or cognitive decline. This is a particular point of contention for aducanumab, an antibody drug that is now on the market for around US$56,000 per year, despite prematurely halted phase III trials and the messy data set that was submitted for approval. © 2021 Springer Nature Limited

Keyword: Alzheimers
Link ID: 28077 - Posted: 11.17.2021

Chloe Tenn Depression affects almost 300 million people globally, and is considered a leading cause of disability by the World Health Organization. As with many diseases, studies that have searched for genetic variations associated with depression have been conducted primarily in people of European ancestry, and there is limited data available on genes linked to depression in non-European ancestry groups. Finding such genetic variations can not only help in assessing individuals’ likelihood of developing depression, but potentially provide insight into how to treat the mental illness by pinpointing the genes and proteins that underlie it. See “Our Aching Brains” Researchers have now conducted the largest genomic study to date on depression in a non-European population, focusing on participants with East Asian ancestry. In a study published on September 29 in JAMA Psychiatry, they reveal that not only were a majority of genetic variants associated with depression in European populations not applicable in East Asian ancestral cohorts, but novel indicators emerged in East Asians that had not been discovered in studies on Europeans. The study’s authors caution that the existing knowledge on genetic risk factors for depression is not generalizable to a global population. “I think it’s a strikingly ambitious effort,” says Andrew Ryder, a cultural-clinical psychologist who specializes in East Asian cultures at Concordia University in Montreal who was unaffiliated with the study. “I see this research as establishing that, even in the hard science aspects of studying humanity, you can’t ignore the social world and the potential influence of culture. . . . It’s too easy for people to assume if we’re doing something scientific, it must be true of people everywhere in the world, rather than building culture into their sense of how their science works.” © 1986–2021 The Scientist

Keyword: Depression; Genes & Behavior
Link ID: 28076 - Posted: 11.17.2021

By David Dobbs Chronic pain is both one of the world’s most costly medical problems, affecting one in every five people, and one of the most mysterious. In the past two decades, however, discoveries about the crucial role played by glia — a set of nervous system cells once thought to be mere supports for neurons — have rewritten chronic pain science. These findings have given patients and doctors a hard-science explanation that chronic pain previously lacked. By doing so, this emerging science of chronic pain is beginning to influence care — not by creating new treatments, but by legitimizing chronic pain so that doctors take it more seriously. Although glia are scattered throughout the nervous system and take up almost half its space, they long received far less scientific attention than neurons, which do the majority of signaling in the brain and body. Some types of glia resemble neurons, with roughly starfish-like bodies, while others look like structures built with Erector sets, their long, straight structural parts joined at nodes. When first discovered in the mid-1800s, glia — from the Greek word for glue — were thought to be just connective tissue holding neurons together. Later they were rebranded as the nervous system’s janitorial staff, as they were found to feed neurons, clean up their waste and take out their dead. In the 1990s they were likened to secretarial staff when it was discovered they also help neurons communicate. Research over the past 20 years, however, has shown that glia don’t just support and respond to neuronal activity like pain signals — they often direct it, with enormous consequences for chronic pain. If you’re hearing this for the first time and you’re one of the billion-plus people on Earth who suffer from chronic pain (meaning pain lasting beyond three to six months that has no apparent cause or has become independent of the injury or illness that caused it), you might be tempted to say that your glia are botching their pain-management job. © 2021 The New York Times Company

Keyword: Pain & Touch; Glia
Link ID: 28075 - Posted: 11.13.2021

by Angie Voyles Askham Two new unpublished studies presented virtually at the 2021 Society for Neuroscience annual meeting offer insights into synapse development: One maps the trajectories of synapse formation across nine species, and the other characterizes the earliest synapses to arise in the human brain. The findings could help researchers better understand how developmental changes may alter synaptic function and contribute to autism. “In order to understand whether something is deviated from neurotypical, you actually have to know what neurotypical is,” says Sam Wang, professor of neuroscience at Princeton University and principal investigator on one of the new studies. Across species, early brain development is defined by a period of exuberant synapse formation, followed by one in which any unnecessary connections are pruned. Disruption to either process may explain some of the atypical development seen in autism, but much about synaptic development remains unknown. For example, when Wang and his colleagues began sifting through the literature to figure out when in development cortical synapses are most abundant and whether that timing shows shared patterns across species, they couldn’t find any studies that had charted the full developmental trajectory from birth to adulthood, says Henk-Jan Boele, a postdoctoral researcher in Wang’s lab who presented the work. So they decided to plot that course themselves, for as many species of mammals as they could find data for. © 2021 Simons Foundation

Keyword: Autism; Development of the Brain
Link ID: 28074 - Posted: 11.13.2021

Sarah Marsh and Hannah Devlin A growing number of private clinics are offering ketamine for depression, according to experts who warn of a potential “wild west” of providers with no national register of patients’ treatment being integrated into overall NHS care. At least six private providers in the UK offer the drug for depression. In March the first service that also includes psychotherapy opened in Bristol, charging £6,000 for a course of low-dose treatments and talking therapy. But health experts expressed concern about creating a two-tier system in which the novel treatment is unavailable to NHS patients. They also warned of “doctor shopping”, where patients go to a ketamine clinic one day and another the next without health professionals being able to keep track of who is getting the drug. Scientists said the NHS healthcare watchdog was taking too long to update its guidance informing clinical practice on prescribing antidepressants in the UK. It was last updated in 2009. Ketamine has a reputation as a party drug because of its short-term dissociative effects but is licensed as an anaesthetic. When abused, the drug can cause long-term problems such as ulcers, pain in the bladder and kidney problems. But it has shown potential in depression treatment trials for those who are resistant to other treatments. Because ketamine is licensed to be used by doctors as an anaesthetic it can be prescribed off-licence for depression, which is what is happening in private clinics. To be prescribed on the NHS, it would need to be approved by the National Institute for Health and Care Excellence (Nice) as a cost-effective treatment. Ketamine would also need to be authorised by the Medicines and Healthcare Regulatory Agency to be marketed as a treatment for depression. © 2021 Guardian News & Media Limited

Keyword: Depression; Drug Abuse
Link ID: 28073 - Posted: 11.13.2021

By Andrew Jacobs APPLE VALLEY, Calif. — Jose Martinez, a former Army gunner whose right arm and both legs were blown off by a roadside bomb in Afghanistan, has a new calling: He’s become one of the most effective lobbyists in a campaign to legalize the therapeutic use of psychedelic drugs across the country. On a Zoom call this spring with Connie Leyva, a Democratic legislator in California who has long opposed relaxing drug laws, Mr. Martinez told her how psilocybin, the psychoactive ingredient in “magic” mushrooms, had helped to finally quell the physical pain and suicidal thoughts that had tormented him. Ms. Leyva says she changed her mind even before the call ended, and she later voted yes on the bill, which is expected to become law early next year. “We ask these men and women to go fight for our freedoms,” she said in an interview. “So if this is something that is helping them live a more normal life, I feel like I shouldn’t stand in the way.” In the two years since Oregon, Washington, D.C., and a half-dozen municipalities decriminalized psilocybin, vets have become leading advocates in the drive to legalize psychedelic medicine, which they credit with helping ease the post-traumatic stress, anxiety and depression that are often tied to their experiences in the military. The campaign has been propelled by the epidemic of suicides among veterans of Iraq and Afghanistan, but also by the national reckoning over the mass incarceration of people on drug charges that has softened public attitudes on prohibition. More than 30,000 service members have taken their own lives in the years since Sept. 11 — four times the number of those who died on the battlefield — and the Department of Veterans Affairs has struggled to address the crisis with the traditional repertoire of pharmacological interventions. © 2021 The New York Times Company

Keyword: Drug Abuse; Depression
Link ID: 28072 - Posted: 11.13.2021

Esther Landhuis Dogs that habitually hear a bell at chow time become classically conditioned to drool at the mere chime, as the physiologist Ivan Pavlov showed in the 1890s: Their brains learn to associate the bell with food and instruct the salivary glands to respond accordingly. More than a century later, in a paper published today in Cell, the neuroimmunologist Asya Rolls has shown that a similar kind of conditioning extends to immune responses. Using state-of-the-art genetic tools in mice, her team at the Technion in Haifa, Israel, identified brain neurons that became active during experimentally induced inflammation in the abdomen. Later, the researchers showed that restimulating those neurons could trigger the same types of inflammation again. “This is an outstanding body of work,” said Kevin Tracey, a neurosurgeon and president of the Feinstein Institutes for Medical Research in Manhasset, New York. It “establishes that the classic concept of immunological memory can be represented in neurons.” Others before Rolls have suggested that the brain could remember and retrieve immune responses, he said, but “she proved it.” Abstractions navigates promising ideas in science and mathematics. Journey with us and join the conversation. Ruslan Medzhitov, an immunologist at the Yale School of Medicine in New Haven, Connecticut, considers the new research “very provocative.” But unlike other groundbreaking studies that push boundaries and challenge conventional concepts, he said that this one also evokes “the ‘Oh, it makes sense’ type of reaction.” All Rights Reserved © 2021

Keyword: Neuroimmunology
Link ID: 28071 - Posted: 11.13.2021

Kate Wild “The skull acts as a bastion of privacy; the brain is the last private part of ourselves,” Australian neurosurgeon Tom Oxley says from New York. Oxley is the CEO of Synchron, a neurotechnology company born in Melbourne that has successfully trialled hi-tech brain implants that allow people to send emails and texts purely by thought. In July this year, it became the first company in the world, ahead of competitors like Elon Musk’s Neuralink, to gain approval from the US Food and Drug Administration (FDA) to conduct clinical trials of brain computer interfaces (BCIs) in humans in the US. Synchron has already successfully fed electrodes into paralysed patients’ brains via their blood vessels. The electrodes record brain activity and feed the data wirelessly to a computer, where it is interpreted and used as a set of commands, allowing the patients to send emails and texts. BCIs, which allow a person to control a device via a connection between their brain and a computer, are seen as a gamechanger for people with certain disabilities. “No one can see inside your brain,” Oxley says. “It’s only our mouths and bodies moving that tells people what’s inside our brain … For people who can’t do that, it’s a horrific situation. What we’re doing is trying to help them get what’s inside their skull out. We are totally focused on solving medical problems.” BCIs are one of a range of developing technologies centred on the brain. Brain stimulation is another, which delivers targeted electrical pulses to the brain and is used to treat cognitive disorders. Others, like imaging techniques fMRI and EEG, can monitor the brain in real time. “The potential of neuroscience to improve our lives is almost unlimited,” says David Grant, a senior research fellow at the University of Melbourne. “However, the level of intrusion that would be needed to realise those benefits … is profound”. © 2021 Guardian News & Media Limited

Keyword: Brain imaging; Language
Link ID: 28070 - Posted: 11.09.2021

By Raleigh McElvery While the brain and spinal cord have their own squad of specialized immune cells, the peripheral immune system is armed with a larger battalion of proteins, cells and entire organs, such as the spleen, that ward off invaders. Over the past decade, researchers have made great progress in understanding how the peripheral immune system affects neural activity: how immune signals that originate outside the central nervous system can affect cognitive processes, social behavior, neurodegeneration, and more. In fact, they have learned that immune cells from the periphery routinely patrol the central nervous system and support its function. In a new study, researchers showed for the first time that—just as the brain remembers people, places, smells, and so on—it also stores what they call “memory traces” of the body’s past infections. Reactivating the same brain cells that encode this information is enough to swiftly summon the peripheral immune system to defend at-risk tissues. In some ways, this is not an entire surprise. It is clear the peripheral immune system is capable of retaining information about past infections to fight off future ones—otherwise, vaccines would not work. But Asya Rolls, a neuroimmunologist at Technion–Israel Institute of Technology and the paper’s senior author, says the study expands this concept of classical immunologic memory. Initially, she was taken aback that the brain could store traces of immune activity and use them to trigger such a precise response. “I was amazed,” she says. Rolls’s team focused on a brain region called the insular cortex, which senses the body’s internal state through visceral signals such as temperature, pain, hunger and—the researchers reasoned—perhaps immune activity. They studied strains of mice with a type of gut inflammation known as colitis and used fluorescent markers to take snapshots of the groups of brain cells in the insular cortex that became active during the infection. © 2021 Scientific American

Keyword: Neuroimmunology
Link ID: 28069 - Posted: 11.09.2021

By Bruce Bower A child’s partial skull found in a remote section of a South African cave system has fueled suspicion that an ancient hominid known as Homo naledi deliberately disposed of its dead in caves. An international team led by paleoanthropologist Lee Berger of University of the Witwatersrand, Johannesburg pieced together 28 skull fragments and six teeth from a child’s skull discovered in a narrow opening located about 12 meters from an underground chamber where cave explorers first found H. naledi fossils (SN: 9/10/15). Features of the child’s skull qualify it as H. naledi, a species with an orange-sized brain and skeletal characteristics of both present-day people and Homo species from around 2 million years ago. “The case is building for deliberate, ritualized body disposal in caves by Homo naledi,” Berger said at a November 4 news conference held in Johannesburg. While that argument is controversial, there is no evidence that the child’s skull was washed into the tiny space or dragged there by predators or scavengers (SN: 4/19/16). Berger’s group describes the find in two papers published November 4 in PaleoAnthropology. In one, Juliet Brophy, a paleoanthropologist at Louisiana State University in Baton Rouge and colleagues describe the youngster’s skull. In the other, paleoanthropologist Marina Elliott of Canada’s Simon Fraser University in Burnaby and colleagues detail new explorations in South Africa’s Rising Star cave system. © Society for Science & the Public 2000–2021.

Keyword: Evolution
Link ID: 28068 - Posted: 11.09.2021

By Marlene Cimons Ruth Obadal, 72, a retired firefighter in Eugene, Ore., was tired of having to constantly switch glasses, one major reason she decided to have cataract surgery. “I needed progressive lenses for reading up close and for distance such as driving,” she says. Moreover, as a volunteer track-and-field official working outdoors, “I also needed the sunglasses version,” she says. “I also had separate glasses for computer and piano, as I needed to see up close and straight ahead, not just down.” U.S. coronavirus cases tracker and map In addition to the inconvenience, she found it increasingly difficult to get crisp vision, even when fine-tuning her prescriptions. So she had the procedure in both eyes — each two weeks apart — in May. She is happy with the results. “Now, I don’t use glasses for anything,” she says. Everyone who ages is vulnerable to developing a cataract in one or both eyes, a cloudy area in the eye’s natural lens that can cause vision to become blurry, hazy and less colorful. Cataracts result from normal changes in the eyes as people get older. At about age 40, the proteins in the lens begin to break down and clump together, causing the cloudiness. Over time, it worsens. Sunlight during the day and nighttime glare from streetlights and cars can be uncomfortable, even painful, interfering with the daily tasks of life, such as driving a vehicle, especially after dark. “I tell my patients that the time for surgery is when you can’t see what you need to do, whether it’s driving, reading the sports scores on bottom of your TV screen or seeing your mobile device,” says Amir Khan, an ophthalmologist at the Mayo Clinic. “We let the patient decide.”

Keyword: Vision
Link ID: 28067 - Posted: 11.09.2021

By Gina Kolata CAMBRIDGE, Mass. — When Sharif Tabebordbar was born in 1986, his father, Jafar, was 32 and already had symptoms of a muscle wasting disease. The mysterious illness would come to define Sharif’s life. Jafar Tabebordbar could walk when he was in his 30s but stumbled and often lost his balance. Then he lost his ability to drive. When he was 50, he could use his hands. Now he has to support one hand with another. No one could answer the question plaguing Sharif and his younger brother, Shayan: What was this disease? And would they develop it the way their father had? As he grew up and watched his father gradually decline, Sharif vowed to solve the mystery and find a cure. His quest led him to a doctorate in developmental and regenerative biology, the most competitive ranks of academic medical research, and a discovery, published in September in the journal Cell, that could transform gene therapy — medicine that corrects genetic defects — for nearly all muscle wasting diseases. That includes muscular dystrophies that affect about 100,000 people in the United States, according to the Muscular Dystrophy Association. Scientists often use a disabled virus called an adeno-associated virus, or AAV, to deliver gene therapy to cells. But damaged muscle cells like the ones that afflict Dr. Tabebordbar’s father are difficult to treat. Forty percent of the body is made of muscle. To get the virus to those muscle cells, researchers must deliver enormous doses of medication. Most of the viruses end up in the liver, damaging it and sometimes killing patients. Trials have been halted, researchers stymied. Dr. Tabebordbar managed to develop viruses that go directly to muscles — very few end up in the liver. His discovery could allow treatment with a fraction of the dosage, and without the disabling side effects. Dr. Jeffrey Chamberlain, who studies therapies for muscular diseases at the University of Washington and is not involved in Dr. Tabebordbar’s research, said the new method, “could take it to the next level,” adding that the same method also could allow researchers to accurately target almost any tissue, including brain cells, which are only beginning to be considered as gene therapy targets. © 2021 The New York Times Company

Keyword: Movement Disorders; Genes & Behavior
Link ID: 28066 - Posted: 11.06.2021