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Alison Abbott Scientists at one of Germany’s leading neuroscience institutes say that their employer, the Max Planck Society (MPS), is failing in its responsibility to defend the institute’s scientists against efforts by animal-rights activists to disrupt research. The criticisms are outlined in two letters to MPS leadership seen by Nature, and in interviews with scientists. They relate to the MPS’s handling of a struggle between animal-rights activists and Nikos Logothetis, a world-renowned neuroscientist who has been a director at the Max Planck Institute for Biological Cybernetics (MPI-Biocyb) in Tübingen since 1996. An expert in visual reception, Logothetis studies how the brain makes sense of the world, and used to run a primate laboratory at MPI-Biocyb. The MPS, which has an annual public budget of €1.8 billion (US$2.1 billion), is Germany’s most prestigious research organization, and runs 84 research institutes and facilities. The struggle began in September 2014, when a German television channel aired footage taken by an undercover animal-welfare activist who had infiltrated Logothetis’s lab, purporting to show mistreatment of research monkeys. Death threats and insults to Logothetis and his family followed — and in 2015, Logothetis decided to wind down his primate lab and replace it with a rodent facility. Events came to a head on 20 February this year, when Logothetis was indicted for allegedly violating animal-protection laws, after an animal-welfare group made complaints to police on the basis of the 2014 footage. Logothetis denies the charges. A trial date has not yet been set. © 2018 Macmillan Publishers Limited,

Keyword: Animal Rights
Link ID: 25039 - Posted: 05.31.2018

Imagine having superhuman hearing. You’re at a noisy, cocktail party and yet your ears can detect normally inaudible sounds made by your friends’ muscles as they lean in to dish the latest gossip. But, unlike normal hearing, each of these sounds causes your ears to react in the same way. There is no difference between the quietest and loudest movements. To your superhuman ears, they all sound loud, like honking horns. According to a study funded by the National Institutes of Health, that may be how a shark’s electrosensing organ reacts when it detects teensy, tiny electrical fields emanating from nearby prey. “Sharks have this incredible ability to pick up nanoscopic currents while swimming through a blizzard of electric noise. Our results suggest that a shark’s electrosensing organ is tuned to react to any of these changes in a sudden, all-or-none manner, as if to say, ‘attack now,’” said David Julius, Ph.D., professor and chair of physiology at the University of California, San Francisco and senior author of the study published in Nature. His team studies the cells and molecules behind pain and other sensations. For instance, their results have helped scientists understand why chili peppers feel hot and menthol cool. Led by post-docs Nicholas W. Bellono, Ph.D. and Duncan B. Leitch, Ph.D., Dr. Julius’ team showed that the shark’s responses may be very different from the way the same organ reacts in skates, the flat, winged, evolutionary cousins of sharks and sting rays, and this may help explain why sharks appear to use electric fields strictly to locate prey while skates use them to find food, friends, and mates. They also showed how genes that encode for proteins called ion channels may control the shark’s unique “sixth sense.”

Keyword: Aggression; Pain & Touch
Link ID: 25038 - Posted: 05.31.2018

By Dhruv Khullar I didn’t think our relationship would last, but neither did I think it would end so soon. My patient had struggled with bipolar disorder his entire life, and his illness dominated our years together. He had, in a fit of hopelessness, tried to take his life with a fistful of pills. He had, in an episode of mania, driven his car into a tree. But the reason I now held his death certificate — his sister and mother in tears by his bed — was more pedestrian: a ruptured plaque in his coronary artery. A heart attack. Americans with depression, bipolar disorder or other serious mental illnesses die 15 to 30 years younger than those without mental illness — a disparity larger than for race, ethnicity, geography or socioeconomic status. It’s a gap, unlike many others, that has been growing, but it receives considerably less academic study or public attention. The extraordinary life expectancy gains of the past half-century have left these patients behind, with the result that Americans with serious mental illness live shorter lives than those in many of the world’s poorest countries. National conversations about better mental health care tend to follow a mass shooting or the suicide of a celebrity. These discussions obscure a more rampant killer of millions of Americans with mental illness: chronic disease. © 2018 The New York Times Company

Keyword: Schizophrenia; Depression
Link ID: 25037 - Posted: 05.31.2018

Alison Abbott Depression affects one in four people at some time in their lives. It is often difficult to treat, in part because its causes are still debated. Psychiatrist Edward Bullmore is an ardent proponent of a radical theory now gaining traction: that inflammation in the brain may underlie some instances. His succinct, broad-brush study, The Inflamed Mind, looks at the mounting evidence. The book outlines a persuasive case for the link between brain inflammation and depression. Bullmore pleads with the medical profession to open its collective mind, and the pharmaceutical industry to open its research budget, to the idea. He provides a current perspective on how the science of psychiatry is slowly emerging from a decades-long torpor. He sees the start of a shift in the Cartesian view that disorders of the body ‘belong’ to physicians, whereas those of the more ‘immaterial’ mind ‘belong’ to psychiatrists. Accepting that some cases of depression result from infections and other inflammation-causing disorders of the body could lead to much-needed new treatments, he argues. In 1989, during his clinical training at St Bartholomew’s Hospital in London, Bullmore encountered a patient whom he calls Mrs P, who had severe rheumatoid arthritis. She left an indelible impression. He examined her physically and probed her general state of mind. He reported to his senior physician, with a certain pride in his diagnostic skill, that Mrs P was both arthritic and depressed. Replied the experienced rheumatologist dismissively, given her painful, incurable physical condition, “You would be, wouldn’t you?” © 2018 Macmillan Publishers Limited,

Keyword: Depression; Neuroimmunology
Link ID: 25036 - Posted: 05.30.2018

Mark Brown Arts correspondent Teenagers are being damaged by the British school system because of early start times and exams at 16 when their brains are going through enormous change, a leading neuroscientist has said. Sarah-Jayne Blakemore said it was only in recent years that the full scale of the changes that take place in the adolescent brain has been discovered. “That work has completely revolutionised what we think about this period of life,” she said. Blakemore, a professor in cognitive neuroscience at University College London, told the Hay festival that teenagers were unfairly mocked and demonised for behaviour they had no control over, whether that was moodiness, excessive risk-taking, bad decision making or sleeping late. The changes in the brain were enormous, she said, with substantial rises in white matter and a 17% fall in grey matter, which affects decision making, planning and self-awareness. All parents know that teenagers would sleep late if they could but it is all to do with brain changes, she said. “It is not because they are lazy, it is because they go through a period of biological change where melatonin, which is the hormone humans produce in the evenings and makes us feel sleepy, is produced a couple of hours later than it is in childhood or adulthood.” They are then forced to go to school when their brain says they should still be sleeping. That is then exacerbated at weekends when teenagers try to catch up by sleeping until lunchtime – what Blakemore called “social jetlag”. © 2018 Guardian News and Media Limited

Keyword: Development of the Brain; Biological Rhythms
Link ID: 25035 - Posted: 05.30.2018

Deep brain stimulation has been used to treat Parkinson’s disease symptoms for 25 years, but limitations have led researchers to look for ways to improve the technique. This study describes the first fully implanted DBS system that uses feedback from the brain itself to fine-tune its signaling. The study was supported by the National Institutes of Health’s Brain Research through Advancing Innovative Technologies (BRAIN) Initiative and the National Institute of Neurological Disorders and Stroke (NINDS). “The novel approach taken in this small-scale feasibility study may be an important first step in developing a more refined or personalized way for doctors to reduce the problems patients with Parkinson’s disease face every day,” said Nick B. Langhals, Ph.D., program director at NINDS and team lead for the BRAIN Initiative. Deep brain stimulation is a method of managing Parkinson’s disease symptoms by surgically implanting an electrode, a thin wire, into the brain. Traditional deep brain stimulation delivers constant stimulation to a part of the brain called the basal ganglia to help treat the symptoms of Parkinson’s. However, this approach can lead to unwanted side effects, requiring reprogramming by a trained clinician. The new method described in this study is adaptive, so that the stimulation delivered is responsive in real time to signals received from the patient’s brain. “This is the first time a fully implanted device has been used for closed-loop, adaptive deep brain stimulation in human Parkinson’s disease patients,” said Philip Starr, M.D., Ph.D., professor of neurological surgery, University of California, San Francisco, and senior author of the study, which was published in the Journal of Neural Engineering.

Keyword: Parkinsons
Link ID: 25034 - Posted: 05.30.2018

A new neck brace for people with motor neurone disease (MND) makes a "substantial difference" to their quality of life, a patient has said. The disease causes muscle wasting, eventually leaving people with the condition unable to support their head. MND patient Philip Brindle said the collar, designed in Sheffield, "opened up opportunities that I do not think I would have had otherwise". The device is now being used by 25 NHS Trusts, according to its designers. MND is a progressive and terminal disease that damages the function of nerves and leads to muscle wasting and mobility problems, among other symptoms. It affects up to 5,000 adults in the UK, according to charity the MND Association. Dr Brian Dickie, director of research development at the association, said the collar has been "preferred by the majority of people who tried it". Image caption Mr Brindle's MND has left him unable to hold his head up independently Mr Brindle, 72, from Chesterfield, said since he was diagnosed with MND in 2015 his head had begun to drop and he did not want to be seen in public. "I just do not have the strength to hold [my head] up anymore and that makes life extremely unpleasant," he said. "You can't read, you can't watch TV, you can't have a conversation with anyone and you can't eat or drink with your head in that position." Image caption The Head Up collar is made from the same material used in space suits The new collar was designed by researchers at the University of Sheffield and Sheffield Hallam University, together with patients and clinicians at Sheffield Teaching Hospital. It has a soft fabric base, made from a material used by NASA to make space suits, on to which a series of shaped supports can be added to provide additional stability. © 2018 BBC

Keyword: ALS-Lou Gehrig's Disease
Link ID: 25033 - Posted: 05.30.2018

By Shawna Williams | Complications during pregnancy can magnify the effect of genetic risk factors for schizophrenia by altering gene expression in the placenta, a new study suggests. The paper appeared yesterday (May 28) in Nature Medicine. “To me the key thing in this paper is the recognition that environmental factors in early development, prenatal factors, are likely to be very important in schizophrenia and just as important as genes,” Allan Brown of Columbia University Medical Center who was not involved in the study tells Scientific American. An international team of researchers analyzed data from nearly 3,000 participants, including people with schizophrenia and healthy controls. The researchers found that, among people with known genetic risk factors, those who were products of a pregnancy complicated by conditions such as preeclampsia or diabetes were at least five times more likely to have the disease than were people born of uncomplicated pregnancies. The researchers also analyzed gene expression in placental tissue from complicated and uncomplicated pregnancies. That assay revealed that genes associated with schizophrenia risk tended to be “turned on” in the placentas from complicated pregnancies, and that higher expression of those genes was associated with inflammation and other signs of stress in the tissue. “We need to create a new risk score for schizophrenia, incorporating not only genes but also placental health,” study coauthor Daniel Weinberger of the Lieber Institute for Brain Research and the Johns Hopkins University School of Medicine tells STAT. “The odds of becoming schizophrenic based on your polygenic risk score is more than 10 times greater with these early-life complications than without them.” © 1986-2018 The Scientist

Keyword: Schizophrenia; Development of the Brain
Link ID: 25032 - Posted: 05.30.2018

By Barry Meier Purdue Pharma, the company that planted the seeds of the opioid epidemic through its aggressive marketing of OxyContin, has long claimed it was unaware of the powerful opioid painkiller’s growing abuse until years after it went on the market. But a copy of a confidential Justice Department report shows that federal prosecutors investigating the company found that Purdue Pharma knew about “significant” abuse of OxyContin in the first years after the drug’s introduction in 1996 and concealed that information. Company officials had received reports that the pills were being crushed and snorted; stolen from pharmacies; and that some doctors were being charged with selling prescriptions, according to dozens of previously undisclosed documents that offer a detailed look inside Purdue Pharma. But the drug maker continued “in the face of this knowledge” to market OxyContin as less prone to abuse and addiction than other prescription opioids, prosecutors wrote in 2006. Based on their findings after a four-year investigation, the prosecutors recommended that three top Purdue Pharma executives be indicted on felony charges, including conspiracy to defraud the United States, that could have sent the men to prison if convicted. But top Justice Department officials in the George W. Bush administration did not support the move, said four lawyers who took part in those discussions or were briefed about them. Instead, the government settled the case in 2007. Prosecutors found that the company’s sales representatives used the words “street value,” “crush,” or “snort” in 117 internal notes recording their visits to doctors or other medical professionals from 1997 through 1999. © 2018 The New York Times Company

Keyword: Drug Abuse
Link ID: 25031 - Posted: 05.29.2018

By Kashmira Gander Scientists have turned off aggressive behavior in mice for weeks at a time by harnessing the power of a little-understood group of brain cells. In a new study, which sheds light on the potential biological cause of aggression, scientists tinkered with neurons in the brains of lab mice. To arrive at their findings, the researchers at the Karolinska Institutet in Sweden investigated the role of a set of neurons in the ventral premammillary nucleus (PMv) of the hypothalamus. Mice generally resort to aggression as a way to assert their dominance rather than cause harm, so the scientists tested their hypothesis using the so-called tube test. This involves pitting two mice against each other in a narrow corridor, in order to document their responses in this socially fraught situation. The study, published in the journal Nature Neuroscience, showed when male mice were confronted with a new male in their home cage, the animals responded aggressively, and showed activity in the PMv neurons. Using a technique where neurons are turned on and off using light, called optogenetics, the researchers were also able to trigger aggressive behavior in mice in scenarios where they were usually calm. In turn, they could stop a mouse mid-attack by turning off the light. What's more, when a generally submissive male was faced with a dominant male, blocking the PMv cells inverted their statuses. As well as aggression, PMv neurons also appeared to be associated with other parts of the brain—the part linked to rewards. © 2018 Newsweek LLC

Keyword: Aggression
Link ID: 25030 - Posted: 05.29.2018

By Dana G. Smith About 60 to 70 percent of a person’s risk for schizophrenia depends on their genes. Most of us have some of the schizophrenia-associated genetic variants—single-letter changes in the DNA of genes scattered across our genome—and the more we have, the greater our risk. At the same time, scientists have known that complications during pregnancy, including viral infections in the mother, increase the fetus’s risk for developing schizophrenia by two-fold, but scientists have been unsure why. New research published in Nature Medicine on May 28 reveals how when these two risk factors interact, the likelihood of an individual eventually being diagnosed with schizophrenia goes up at least five-fold compared to someone with a high genetic risk alone. Daniel Weinberger, director of the Lieber Institute for Brain Development in Baltimore and team discovered that roughly a third of the genes associated with schizophrenia are in the placenta. But certain variations in the DNA of these genes only result in schizophrenia if there are complications during pregnancy. The gene variants likely affect how resilient the placenta is to stress from its environment. If the mother or baby experiences a major health complication during pregnancy, the variants could activate these genes in the placenta and induce inflammation or affect the fetus’s development, increasing the risk for schizophrenia later in life. “The placenta is the missing link between maternal risk factors that complicate pregnancies and the development of the fetal brain and the emergence of developmental behavioral disorders,” Weinberger says. © 2018 Scientific American

Keyword: Schizophrenia; Development of the Brain
Link ID: 25029 - Posted: 05.29.2018

By Victoria Gill Science correspondent, BBC News Scientists working with dolphins at a marine park near Paris have attempted to measure how the animals feel about aspects of their lives in captivity. In what researchers say is the first project to examine captivity "from the animals' perspective", the team assessed what activities dolphins looked forward to most. They found that the marine mammals most keenly anticipated interacting with a familiar human. The results, they say, show that "better human-animal bonds equals better welfare". The study, published in the journal Applied Animal Behaviour Science, was part of a three-year project to measure dolphin welfare in a captive setting. Lead researcher Dr Isabella Clegg worked at Parc Astérix, a theme park with one of France's largest dolphinariums. With colleagues at the University of Paris animal behaviour lab, she designed experiments to decode dolphin behaviour - essentially looking for physical postures that indicate how the animals were feeling. "We wanted to find out what activities in captivity they like most," Dr Clegg told the BBC. To work this out, she tested three activities: a trainer coming and playing with dolphins; adding toys to the pool; and a control, which meant leaving the dolphins to their own devices. "We found a really interesting result - all dolphins look forward most to interacting with a familiar human," Dr Clegg said. The animals showed this anticipation by "spy hopping", the action of peering above the surface and looking in the direction that trainers usually approached from. The dolphins would also increase their level of activity in the pool and spend more time at the edge. "We've seen this same thing in other zoo animals and in farm animals," said Dr Clegg, adding: "Better human-animal bonds equals better welfare." © 2018 BBC.

Keyword: Animal Rights; Emotions
Link ID: 25028 - Posted: 05.29.2018

Vanessa Romo Bay mussels in Washington's Puget Sound have tested positive for trace amounts of oxycodone, providing more evidence that the opioid prescription medication is truly ubiquitous. Researchers at the Puget Sound Institute who analyzed the mussels said the discovery of pharmaceuticals and illicit drugs in harbors in the Seattle and Bremerton areas is not uncommon — but the organization noted this is the first time that opioids have been found in local shellfish. "We found antibiotics, we found antidepressants, chemotherapy drugs, heart medications and also oxycodone," biologist Jennifer Lanksbury, who led the Washington Department of Fish and Wildlife study, told K5 News. Scientists determined that the slew of medications are passed into the Puget Sound through discharge from wastewater treatment plants. The analysis is part of the state's biennial Puget Sound Mussel Monitoring Program, in which uncontaminated mussels are transplanted into various locations to study pollution levels. The reason mussels are the preferred test subject to track toxins in marine life is because they are filter feeders, eating microscopic plants and animals that they strain out of seawater. In the process, "they pick up all sorts of contaminants, so at any given time their body tissues record data about water quality over the previous two to four months," the institute explains. © 2018 npr

Keyword: Drug Abuse
Link ID: 25027 - Posted: 05.26.2018

By Matthew Hutson It's a Saturday morning in February, and Chloe, a curious 3-year-old in a striped shirt and leggings, is exploring the possibilities of a new toy. Her father, Gary Marcus, a developmental cognitive scientist at New York University (NYU) in New York City, has brought home some strips of tape designed to adhere Lego bricks to surfaces. Chloe, well-versed in Lego, is intrigued. But she has always built upward. Could she use the tape to build sideways or upside down? Marcus suggests building out from the side of a table. Ten minutes later, Chloe starts sticking the tape to the wall. "We better do it before Mama comes back," Marcus says in a singsong voice. "She won't be happy." (Spoiler: The wall paint suffers.) Implicit in Marcus's endeavor is an experiment. Could Chloe apply what she had learned about an activity to a new context? Within minutes, she has a Lego sculpture sticking out from the wall. "Papa, I did it!" she exclaims. In her adaptability, Chloe is demonstrating common sense, a kind of intelligence that, so far, computer scientists have struggled to reproduce. Marcus believes the field of artificial intelligence (AI) would do well to learn lessons from young thinkers like her. Researchers in machine learning argue that computers trained on mountains of data can learn just about anything—including common sense—with few, if any, programmed rules. These experts "have a blind spot, in my opinion," Marcus says. "It's a sociological thing, a form of physics envy, where people think that simpler is better." He says computer scientists are ignoring decades of work in the cognitive sciences and developmental psychology showing that humans have innate abilities—programmed instincts that appear at birth or in early childhood—that help us think abstractly and flexibly, like Chloe. He believes AI researchers ought to include such instincts in their programs. © 2018 American Association for the Advancement of Science.

Keyword: Learning & Memory; Development of the Brain
Link ID: 25026 - Posted: 05.26.2018

By Abby Olena Activating or suppressing neuronal activity with ultrasound has shown promise both in the lab and the clinic, based on the ability to focus noninvasive, high-frequency sound waves on specific brain areas. But in mice and guinea pigs, it appears that the technique has effects that scientists didn’t expect. In two studies published today (May 24) in Neuron, researchers demonstrate that ultrasound activates the brains of rodents by stimulating an auditory response—not, as researchers had presumed, only the specific neurons where the ultrasound is focused. “These papers are a very good warning to folks who are trying to use ultrasound as a tool to manipulate brain activity,” says Raag Airan, a neuroradiologist and researcher at Stanford University Medical Center who did not participate in either study, but coauthored an accompanying commentary. “In doing these experiments going forward [the hearing component] is something that every single experimenter is going to have to think about and control,” he adds. Over the past decade, researchers have used ultrasound to elicit electrical responses from cells in culture and motor and sensory responses from the brains of rodents and primates. Clinicians have also used so-called ultrasonic neuromodulation to treat movement disorders. But the mechanism by which high frequency sound waves work to exert their influence is not well understood. © 1986-2018 The Scientist

Keyword: Hearing
Link ID: 25025 - Posted: 05.26.2018

Being discharged from a hospital trauma center after receiving treatment for a traumatic brain injury (TBI) does not necessarily mean that a patient has fully recovered. TBI can lead to long-lasting physical and cognitive symptoms, but a new study in JAMA Network Open suggests that many patients may not be receiving follow-up care. Patients in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI (link is external)) initiative, a large, long-term, NIH-funded study of patients who are treated at the emergency room for mild TBI or concussion, were surveyed about their care after hospital discharge. Follow-up care in this study referred to receiving TBI-related educational materials at discharge, a call from the hospital within two weeks after release, seeing a healthcare provider within two weeks, or seeing a healthcare provider within three months. According to the findings, 44 percent of the 831 patients who completed questionnaires 2 weeks and 3 months after sustaining TBI reported seeing a doctor or other provider within three months. Of those patients, 15 percent visited a clinic that specialized in head injury. Approximately half of the patients saw a general practitioner and close to a third reported seeing more than one type of doctor. Additionally, among the 279 patients with three or more moderate-to-severe post-concussive symptoms, 41 percent had not had a follow-up visit at three months after discharge. Approximately half of the patients were discharged without TBI educational materials.

Keyword: Brain Injury/Concussion
Link ID: 25024 - Posted: 05.26.2018

By Nicholas Bakalar Bedtime reading with a tablet or smartphone can interfere with a good night’s sleep, some studies and many anecdotal reports suggest. Now researchers have conducted a small experiment to test the idea. Scientists had nine people spend 10 nights in a sleep laboratory. For five consecutive nights, they read before sleep with an iPad; then they read print for five nights. In both scenarios, they read in a dimly lit room until they felt ready to go to sleep. The experiment, described in Physiological Reports, found that when people used iPads instead of reading print, they selected a later bedtime and had a later sleep onset. They also had suppressed levels of melatonin, the hormone that regulates sleep, and delayed time to melatonin secretion. Periods of REM sleep — the rapid eye movements of the dreaming stage of sleep — were reduced when they used the iPad rather than printed material. The volunteers also reported feeling less sleepy in the evening, and less alert in the morning after using the electronic device. “These devices are not benign,” said a co-author of the study, Jeanne F. Duffy, a neuroscientist at Brigham and Women’s Hospital in Boston. “They have biological effects on us. They can be bad for adults, but really bad for kids and adolescents who already don’t get enough sleep.” © 2018 The New York Times Company

Keyword: Biological Rhythms; Sleep
Link ID: 25023 - Posted: 05.26.2018

By Judith Graham, You’ve turned 65 and exited middle age. What are the chances you’ll develop cognitive impairment or dementia in the years ahead? New research about “cognitive life expectancy”—how long older adults live with good versus declining brain health—shows that after age 65 men and women spend more than a dozen years in good cognitive health, on average. And, over the past decade, that time span has been expanding. By contrast, cognitive challenges arise in a more compressed time frame in later life, with mild cognitive impairment (problems with memory, decision-making or thinking skills) lasting about four years, on average, and dementia (Alzheimer’s disease or other related conditions) occurring over 1½ to two years. Even when these conditions surface, many seniors retain an overall sense of well-being, according to new research presented last month at the Population Association of America’s annual meeting. “The majority of cognitively impaired years are happy ones, not unhappy ones,” said Anthony Bardo, a co-author of that study and assistant professor of sociology at the University of Kentucky-Lexington. Recent research finds that: Most seniors don’t have cognitive impairment or dementia. Of Americans 65 and older, about 20 to 25 percent have mild cognitive impairment while about 10 percent have dementia, according to Dr. Kenneth Langa, an expert in the demography of aging and a professor of medicine at the University of Michigan. Risks rise with advanced age, and the portion of the population affected is significantly higher for people over 85. © 2018 Scientific American

Keyword: Alzheimers
Link ID: 25022 - Posted: 05.25.2018

By Jim Daley The organizer, a group of cells in the embryo that directs the developmental fates and morphogenesis of other embryonic cells, has been identified in human tissue for the first time, according to a study published today (May 23) in Nature. The discovery demonstrates that the organizer is evolutionarily conserved from amphibians to humans. “For many of us this was always the Holy Grail” of developmental biology, says Guillermo Oliver, the director of the Northwestern Feinberg School of Medicine’s Center for Vascular and Developmental Biology, who was not involved in the study. “The fact that now you can take stem cells and recapitulate those properties with the combination of actors reported here . . . is quite remarkable.” Rockefeller University embryologist Ali Brivanlou and colleagues report that when they grafted human stem cells that they’d treated with Wnt and Activin, two signaling proteins previously shown to be involved in organizer gene expression in other animals, into chick embryos, the grafted cells set off the developmental progress of the cells around them. The experiment establishes for the first time that the organizer exists in humans and that Wnt and Activin work in concert to make it possible for cells to direct embryonic development. S The search for the organizer, and with it the field of modern embryology, began nearly a century ago. Hilde Mangold, a PhD candidate in the lab of German zoologist Hans Spemann, wrote a dissertation in 1924 that described the organizer for the first time. Mangold and Spemann observed a distinct shape and morphology in some of the cells along the neural axis—the portion of the embryo that will become the central nervous system and one of the first structures to form during development—in a salamander embryo. When they grafted these cells from one embryo to another, the transplanted cells induced the formation of a second developmental axis in that embryo. Spemann would go on to receive the 1935 Nobel Prize in Physiology or Medicine for the discovery; Mangold died before then in an accident. © 1986-2018 The Scientist

Keyword: Development of the Brain
Link ID: 25021 - Posted: 05.25.2018

By GINA KOLATA The first of a new class of drugs to prevent migraines was approved last week. The medication, called Aimovig, reduces the frequency of migraines among those severely afflicted, but the drug rarely prevents these episodes altogether. One expert called it “progress but not a panacea.” Migraine is the most disabling neurological disease in the world among people under age 50, beating epilepsy, strokes and chronic back pain. Yet many who have migraines don’t realize it or ever mention their symptoms to a doctor. Migraines are not just headaches. It is diagnosed in patients only if they have had a minimum of five attacks, each lasting four to 72 hours. Each attack has to include at least two of the following symptoms: throbbing headache with pain that is moderate to severe, that worsens with activity, and is only on only one side of the head. Also, a person suffering a migraine attack is nauseated or abhors sound or noise. What about auras? Are they part of a migraine? Sometimes, but not always. About 20 percent of migraine patients get an aura before the headache. Auras involve distortions of vision. People see jagged lights or have blind spots in their visual field. But auras can take other forms as well: a prickling pins-and-needles feeling on parts of the body, speech disturbances, distortions of sounds. Some get auras without a headache or only a mild headache. Auras actually involve different areas of the brain than migraines, and it is not clear why they are linked to migraine headaches. How common are migraines? They can start in childhood, although they usually begin in adolescence or young adulthood. They strike nearly one in five women worldwide, one in 16 men and one in 11 children. One out of four households has at least one member with migraine. The condition seems to spring from a combination of genetic and environmental factors. There is nothing a person can do to reduce the odds of developing migraine. © 2018 The New York Times Company

Keyword: Pain & Touch
Link ID: 25020 - Posted: 05.25.2018