By James Gorman If you want to know what makes hummingbirds tick, it’s best to avoid most poetry about them. Bird-beam of the summer day, — Whither on your sunny way? Whither? Probably off to have a bloodcurdling fight, that’s whither. John Vance Cheney wrote that verse, but let’s not point fingers. He has plenty of poetic company, all seduced by the color, beauty and teeny tininess of the hummingbird but failed to notice the ferocity burning in its rapidly beating heart. The Aztecs weren’t fooled. Their god of war, Huitzilopochtli, was a hummingbird. The Aztecs loved war, and they loved the beauty of the birds as well. It seems they didn’t find any contradiction in the marriage of beauty and bloodthirsty aggression. Scientists understood that aggression was a deep and pervasive part of hummingbird life. But they, too, have had their blind spots. The seemingly perfect match of nectar-bearing flowers to slender nectar-sipping beaks clearly showed that hummingbirds were shaped by co-evolution. It seemed clear that, evolutionarily, plants were in charge. Their need for reliable pollinators produced flowers with a shape that demanded a long slender bill. Hummingbird evolution obliged. But hummingbirds also heard the call of battle, which demanded a different evolutionary course. Some of those slender, delicate beaks have been reshaped into strong, sharp and dangerous weapons. In a recent paper organizing and summing up 10 years of research, Alejandro Rico-Guevara and his colleagues at the University of California, Berkeley, shared evidence gathered by high-speed video about how the deadly beaks are deployed in male-to-male conflict. Like the horns of bighorn sheep or the giant mandibles of stag beetles, hummingbird beaks are used to fight off rivals for mates. This is sexual selection, a narrow part of natural selection, in which the improvement of mating chances is the dominant force. © 2019 The New York Times Company

Keyword: Aggression; Evolution
Link ID: 25937 - Posted: 02.06.2019

Sujata Gupta The task was designed to scare the kids. One by one, adults guided children, ranging in age from 3 to 7, into a dimly lit room containing a mysterious covered mound. To build anticipation, the adults intoned, “I have something in here to show you,” or “Let’s be quiet so it doesn’t wake up.” The adult then uncovered the mound — revealed to be a terrarium — and pulled out a realistic looking plastic snake. Throughout the 90-second setup, each child wore a small motion sensor affixed to his or her belt. Those sensors measured the child’s movements, such as when they sped up or twisted around, at 100 times per second. Researchers wanted to see if the movements during a scary situation differed between children diagnosed with depression or anxiety and children without such a diagnosis. It turns out they did. Children with a diagnosis turned further away from the perceived threat — the covered terrarium — than those without a diagnosis. In fact, the sensors could identify very young children who have depression or anxiety about 80 percent of the time, researchers report January 16 in PLOS One. Such a tool could be useful because, even as it’s become widely accepted that children as young as age 3 can suffer from mental health disorders, diagnosis remains difficult. Such children often escape notice because they hold their emotions inside. It’s increasingly clear, though, that these children are at risk of mental and physical health problems later in life, says Lisabeth DiLalla, a developmental psychologist at Southern Illinois University School of Medicine in Carbondale. “The question is: ‘Can we turn that around?’” |© Society for Science & the Public 2000 - 2019

Keyword: Development of the Brain; Depression
Link ID: 25936 - Posted: 02.06.2019

By Jen Gunter Pregnant women are given a long list of medical recommendations that can come across as patriarchal don’ts: Don’t eat raw fish. Don’t consume deli meats. Don’t do hot yoga! Don’t drink. There’s scientific evidence that these activities can have negative impacts on the health of the fetus, but the one that seems to be the source of most debate is alcohol. After all, the French do it, don’t they? And many people born in the 1960s or earlier had mothers who drank. And we’re fine, right? My mother had a fairly regular glass of rye and ginger ale when she was pregnant with me. And she smoked. And I graduated from medical school at the age of 23. So my opinion, especially as someone who believes strongly in a woman’s right to make decisions about her own body, may come as a surprise: It’s medically best not to drink alcohol in pregnancy. Not even a little. The source of that viewpoint? My training and practice as an OB/GYN. Some attribute this abstinence approach to the patriarchy: Clearly we doctors know that moderate alcohol is safe (we don’t!), and we just don’t trust women with that knowledge. According to this theory, we think a woman who hears that an occasional drink is O.K. will blithely go on a bender. (We don’t think that.) Some also say that, in an effort to avoid frivolous lawsuits, doctors advise against alcohol while using a nudge-nudge-wink-wink to insinuate that a glass or two is fine. But this isn’t about sexism (not this time) or dodging litigation. This is about facts. How women use those facts is, of course, their choice. The truth is that fetal alcohol syndrome is far more common than people think, and we have no ability to say accurately what level of alcohol consumption is risk free. © 2019 The New York Times Company

Keyword: Development of the Brain; Drug Abuse
Link ID: 25935 - Posted: 02.06.2019

Catherine Offord Researchers in the UK and New Zealand have created the largest-ever database of protein expression changes associated with Alzheimer’s disease, according to a study published today (February 4) in Communications Biology. The data, which are freely available to researchers online, reveal new insights into the brain areas affected by Alzheimer’s, as well as the molecular pathways leading to the disease. “This database provides a huge opportunity for dementia researchers around the world to progress and to follow-up new areas of biology and develop new treatments,” study coauthor Richard Unwin of the University of Manchester says in a statement. “It’s very exciting to be able to make these data public so scientists can access and use this vital information.” The team analyzed the expression data of more than 5,500 proteins spanning six brain regions in postmortem tissue of nine healthy and nine Alzheimer’s-affected patients. The results provide a map of changes associated with the disease, identifying certain areas of the brain as more affected than others. Heavily affected areas include the hippocampus, the entorhinal cortex, and the cingulate gyrus, the analysis showed. The researchers also found that the cerebellum, an area of the brain thought to be less damaged by Alzheimer’s disease, showed substantial changes in protein expression, but that these changes qualitatively differed from those in other regions. © 1986 - 2019 The Scientist

Keyword: Alzheimers
Link ID: 25934 - Posted: 02.06.2019

Jon Hamilton Women tend to have more youthful brains than their male counterparts — at least when it comes to metabolism. While age reduces the metabolism of all brains, women retain a higher rate throughout the lifespan, researchers reported Monday in the journal Proceedings of the National Academy of Sciences. "Females had a younger brain age relative to males," says Dr. Manu Goyal, an assistant professor of radiology and neurology at Washington University School of Medicine in St. Louis. And that may mean women are better equipped to learn and be creative in later life, he says. The finding is "great news for many women," says Roberta Diaz Brinton, who wasn't connected with the study and directs the Center for Innovation in Brain Science at the University of Arizona Health Sciences. But she cautions that even though women's brain metabolism is higher overall, some women's brains experience a dramatic metabolic decline around menopause, leaving them vulnerable to Alzheimer's. The study came after Goyal and a team of researchers studied the brain scans of 205 people whose ages ranged from 20 to 82. Positron emission tomography scans of these people assessed metabolism by measuring how much oxygen and glucose was being used at many different locations in the brain. The team initially hoped to use the metabolic information to predict a person's age. So they had a computer study how metabolism changed in both men and women. © 2019 npr

Keyword: Sexual Behavior; Brain imaging
Link ID: 25933 - Posted: 02.05.2019

By Elizabeth Pennisi Of all the many ways the teeming ecosystem of microbes in a person’s gut and other tissues might affect health, its potential influences on the brain may be the most provocative. Now, a study of two large groups of Europeans has found several species of gut bacteria are missing in people with depression. The researchers can’t say whether the absence is a cause or an effect of the illness, but they showed that many gut bacteria could make substances that affect nerve cell function—and maybe mood. “It’s the first real stab at tracking how” a microbe’s chemicals might affect mood in humans, says John Cryan, a neuroscientist at University College Cork in Ireland who has been one of the most vocal proponents of a microbiome-brain connection. The study “really pushes the field from where it’s been” with small studies of depressed people or animal experiments. Interventions based on the gut microbiome are now under investigation: The University of Basel in Switzerland, for example, is planning a trial of fecal transplants, which can restore or alter the gut microbiome, in depressed people. Several studies in mice had indicated that gut microbes can affect behavior, and small studies of people suggested this microbial repertoire is altered in depression. To test the link in a larger group, Jeroen Raes, a microbiologist at the Catholic University of Leuven in Belgium, and his colleagues took a closer look at 1054 Belgians they had recruited to assess a “normal” microbiome. Some in the group—173 in total—had been diagnosed with depression or had done poorly on a quality of life survey, and the team compared their microbiomes with those other participants. Two kinds of microbes, Coprococcus and Dialister, were missing from the microbiomes of the depressed subjects, but not from those with a high quality of life. The finding held up when the researchers allowed for factors such as age, sex, or antidepressant use, all of which influence the microbiome, the team reports today in Nature Microbiology. They also found the depressed people had an increase in bacteria implicated in Crohn disease, suggesting inflammation may be at fault. © 2018 American Association for the Advancement of Science

Keyword: Depression
Link ID: 25932 - Posted: 02.05.2019

By Perri Klass, M.D. I believe my mother thought that needing to medicate her own discomfort would be a kind of moral and physical weakness. This applied only to herself; if I told her that I was hurting, or that one of her grandchildren was in pain, she would have been anxious for something to help. She felt our pain, you might say, but she denied her own. I’ve spent the past couple of weeks thinking about pain in children and writing about pain in children — acute pain and chronic pain, pain with shots and pain after surgery, pain medicines and pain specialists. I asked the pain experts I interviewed about the different ways that different people experience pain from the same stimulus: Why does one child cry inconsolably after a needle stick while another, same age, same size needle, watches with curiosity as the shot is administered and doesn’t even flinch? There is a great deal of variation in how much pain people experience, I was told, and by and large we should take people at their word. Some people are more prone to soreness, some are relatively less sensitive, some hypersensitive, and there are differences in the ways that different people process pain, and in the ways they respond to drugs. And “hypersensitive” is not a code word for “complains more” — it’s a neurological category. And then of course there are psychological factors. That is not to say that pain is psychogenic, said Dr. Charles Berde, the founder of the division of pain medicine at Boston Children’s Hospital, and one of my teachers when I did my training there. People who are anxious or terrified of pain, people who have post-traumatic stress disorder, may actually experience more pain, he said, because the pain circuits in their brains are revved up. © 2019 The New York Times Company

Keyword: Pain & Touch
Link ID: 25931 - Posted: 02.04.2019

/ By Ronnie Cohen Dr. Samir Grover was taken aback when, early in his gastroenterology career, he saw one physician speak two times and present contradictory conclusions about the same medication. Each time, the speaker presented identical data on a drug used to treat inflammatory bowel disease. First, he recommended the pharmaceutical. A week later, he deemed it ineffective. “How could this exact same data be spun in two very different ways?” asked Grover, a professor at the University of Toronto. One fact did change — the drug manufacturer that sponsored and paid for the lecture. “Simply following clinical practice guidelines could lead doctors — even those who shun all industry gifts — to unwittingly dispense financially tainted medicine” It’s no secret that drug makers pay doctors to hype their products to other doctors. But few outside the halls of hospitals witness physicians bending a single set of facts in opposing ways. After watching similar acts of statistical wizardry throughout his nine years of medical practice, Grover set out to investigate a more sweeping question about conflicts of interest. Do they infect clinical practice guidelines? Professional societies produce thousands of these documents every year. They steer the decisions of health care professionals and insurance companies about how to prevent and treat an ever-widening range of conditions — from diabetes, hypertension, and heart disease to arthritis, hepatitis, cancer, and depression. Grover and his colleagues’ paper and a companion study recently published in JAMA Internal Medicine suggest that simply following clinical practice guidelines could lead doctors — even those who shun all industry gifts — to unwittingly dispense financially tainted medicine. More than half of the authors of guidelines examined in the two studies had financial conflicts of interest. In many cases, the doctors who wrote the guidelines were paid by the same companies that produced the drugs they recommended. In addition, a significant portion of the doctors who took pharmaceutical money failed to disclose the payments, many of which amounted to $10,000 or more. Copyright 2019 Undark

Keyword: Drug Abuse
Link ID: 25930 - Posted: 02.04.2019

by Esmé Weijun Wang "Schizophrenia terrifies." Those are the first two words of The Collected Schizophrenias, Esmé Weijun Wang's new book — part memoir, part scientific chronicle of her journey towards a diagnosis of schizoaffective disorder. She first noticed that her brain worked differently than others, she says, when she was just five or six years old. And then, she says, "severe depression started when I was about 11, depression that was diagnosed by a doctor probably happened when I was 15 or 16. Bipolar disorder was diagnosed when I was about 17 or 18, and then the schizoaffective disorder, bipolar type, was diagnosed when I was in my late 20s." Interview Highlights On her experience of schizoaffective disorder I like to kind of jokingly say that it's like a marriage between schizophrenia and bipolar disorder. So my first hallucination that I ever had was actually when I was in the shower in college, and I heard a voice very clearly say to me, "I hate you." And it was so clear to me, and this is why I say that hallucinations really effectively kidnap the senses, because it's exactly like someone is standing next to you and saying this thing to you. And I started thinking, oh, is there something going on with the pipes, where I can hear maybe something on the floor below me, or maybe the floor above me, but it didn't really make sense to me physically, so I started thinking, maybe this is a hallucination, and it kind of went off from there ... and then later I started having delusions in which I was believing that my loved ones were replaced by doubles, or replaced by robots — so it's been an interesting journey. © 2019 npr

Keyword: Schizophrenia
Link ID: 25929 - Posted: 02.04.2019

By Jordana Cepelewicz Genitals are among the fastest-evolving features in the animal kingdom. They’re also among the most diverse, arrayed in all shapes and sizes, adorned with spines, hooks and even teeth. Ducks have corkscrew-shaped genitalia. The male sea horse has a brood pouch that receives his mate’s eggs for fertilization and in which he nurtures the resulting offspring until birth. Female cabbage white butterflies have a hinged jaw inside their genital tract. Nature is full of strange reproductive organs with unusual uses. For the most part, though, certain genital morphologies are associated with males, others with females. But in 2014, a tiny insect called the barklouse broke even that rule when researchers reported that the females of all four species of a genus found in the caves of Brazil had a penis. It didn’t just look like a penis but acted like one, too: a penetrative organ the female insects used to anchor themselves to their mates during copulation. Moreover, complementary changes in the genitalia of the males had left them with a small pumping mechanism inside a membranous “vagina-like” cavity. Content from The Coca-Cola Company Sustainability and closed-loop recycling systems must now become a global priority, from emerging nations to the world's largest economies. Read More The finding not only piqued widespread interest (and amusement — the team was awarded a comedic Ig Nobel Prize in 2017), but also led to a debate about whether the scientists involved were correct to refer to the structure, called a gynosome, as a “female penis.” (Some experts, for instance, disagree with that characterization because the gynosome collects sperm rather than delivering it.) © 1996-2019 The Washington Post

Keyword: Sexual Behavior; Evolution
Link ID: 25928 - Posted: 02.04.2019

By Howard M. Fillit Alzheimer's disease is the sixth leading cause of death in the U.S., and unlike with cancer and heart disease, we lack the tools to effectively diagnose and treat it. In sharp contrast to other illnesses and despite many efforts, huge expense and hundreds of clinical trials, no new treatments have been approved in the past 16 years. The emphasis has been on drugs targeting beta-amyloid proteins, which clump into plaques in the brains of afflicted people. Unfortunately, these approaches have not yet yielded the results we hoped for. So now it is time to target novel pathways to tackle this incredibly complex disease. This has been a challenge because of the absence of affordable and noninvasive tests based on biomarkers that doctors can easily use in their offices. The alternatives have been expensive and invasive spinal taps or neuroimaging tests that can be performed only in a hospital or freestanding radiology office. New biomarkers are needed for specific molecular targets that can be used to subtype patients; for predicting the likelihood that they will acquire Alzheimer's; and possibly for providing a diagnosis even before symptoms are noticeable, enabling prevention. That is, they could do what currently available amyloid positron-emission tomography (PET) scans and cerebrospinal fluid tests do. Biomarkers can also be used to enroll patients in clinical trials directed to a specific target, such as beta-amyloid, and to measure how the body responds to a treatment—as was done most recently by Biogen with its anti-beta-amyloid monoclonal antibody. Ultimately biomarkers can determine which therapies would be most effective for an individual. © 2019 Scientific American

Keyword: Alzheimers
Link ID: 25927 - Posted: 02.02.2019

Jef Akst Whether you’re an early bird or a night owl is partly dependent on your genome, according to a study published this week (January 29) in Nature Communications. Scanning nearly 700,000 human genomes available through the UK Biobank and the consumer genetics testing company 23andMe and comparing the results with reported sleep preferences, an international team of researchers identified more than 350 variations associated with being a morning person. Additional analyses using the device-recorded activity patterns of more than 85,000 of these participants revealed that people who carried the most gene variants linked with being an early bird went to bed an average of 25 minutes earlier than those who carried the fewest. The team went on to study the potential roles of these gene variants, and found that many had functions in regulating circadian rhythms. Some were active in the brain, while others were active in the retina. One of the genes participates in the body’s responses to caffeine and nicotine. But, coauthor Michael Weedon, a bioinformaticist at the University of Exeter in the UK, tells The New York Times, “the most interesting ones are the ones where we don’t know what it is.” The researchers found links between people’s sleep preferences, or chronotypes, and their mental health, with those who identified as morning people being less likely to report having depression or schizophrenia and reporting higher levels of general well-being. But chronotype is not a simple variable, Suzanne Hood, an assistant professor of psychology at Bishop’s University in Quebec who was not involved in the study, tells CNN, and future studies should take the nuance of the phenotype into account. “It would be interesting to follow up these findings with other kinds of methods that can track sleep variables with more precision.” © 1986 - 2019 The Scientist.

Keyword: Biological Rhythms; Genes & Behavior
Link ID: 25926 - Posted: 02.02.2019

Emily Conover Lasers can send sounds straight to a listener’s ear, like whispering a secret from afar. Using a laser tuned to interact with water vapor in the air, scientists created sounds in a localized spot that were loud enough to be picked up by human hearing if aimed near a listener’s ear. It’s the first time such a technique can be used safely around humans, scientists from MIT Lincoln Laboratory in Lexington, Mass., report in the Feb. 1 Optics Letters. At the wavelengths and intensities used, the laser won’t cause burns if it grazes eyes or skin. The scientists tested out the setup on themselves in the laboratory, putting their ears near the beam to pick up the sound. “You move your head around, and there’s a couple-inch zone where you go ‘Oh, there it is!’… It’s pretty cool,” says physicist Charles Wynn. The researchers also used microphones to capture and analyze the sounds. The work relies on a phenomenon called the photoacoustic effect, in which pulses of light are converted into sound when absorbed by a material, in this case, water vapor. Based on this effect, the researchers used two different techniques to make the sounds. The first technique, which involves rapidly ramping the intensity of the laser beam up and down, can transmit voices and songs. “You can hear the music really well; you can understand what people are saying,” says physicist Ryan Sullenberger, who coauthored the study along with Wynn and physicist Sumanth Kaushik. |© Society for Science & the Public 2000 - 2019.

Keyword: Hearing
Link ID: 25925 - Posted: 02.02.2019

Jonathan Lambert It's cold outside, you're sick and all you want to do is curl up under the covers until you feel better. In fact, the need for sleep can be so strong when we're sick that this may be all we can do. Scientists don't fully understand how this excessive sleepiness is different from your normal, everyday tiredness. Previous work in nematodes found a gene that dampens activity of wakefulness neurons in response to infection. Other research in mammals suggests elements of the immune response can influence behavior. Overall, scientists still have a lot to learn about what makes us feel sleepy, when we're healthy or sick. Some genes have been identified that seem to affect sleep, but none that actively induce sleepiness when turned on. But a study, published Thursday in the journal Science, finds one potential piece of the puzzle — in fruit flies. Scientists discovered a single protein that both puts flies to sleep when they're sick and also has antimicrobial properties. "This is a very interesting finding," says Dragana Rogulja, a sleep neurobiologist at Harvard who wasn't involved in the study. "It's pretty clear that infection or something that requires an immune response does lead to sleep, and this gene seems to do that." Neuroscientist Amita Sehgal led the study at the University of Pennsylvania's Perelman School of Medicine. She didn't set out to find a gene linked to both sleep and immunity. Instead, her lab was interested in understanding the molecular triggers of sleep. © 2019 npr

Keyword: Sleep; Neuroimmunology
Link ID: 25924 - Posted: 02.01.2019

/ By Jacob Appel One of the most upsetting illnesses any psychiatrist encounters is Wernicke-Korsakoff Syndrome (WKS). Caused by a deficiency of thiamine (vitamin B1), it results in devastating impairment of muscle control and memory. Able-bodied men and women develop a severe and irreversible amnesia that wipes clean their pasts and prevents them from forming new memories. Those who survive — and many patients don’t — are often relegated to nursing homes. Yet the neurological damage WKS causes is only part of what makes it so upsetting to emergency room psychiatrists; after all, many neurological and psychiatric illnesses inflict irreversible cognitive harm. The tragedy of WKS is that, with appropriate public health measures, it could be easily prevented. Historically, thiamine deficiency afflicted the indigent, prisoners of war, and societies with rice-based diets. Its most serious chronic manifestation, beriberi, can present in a “wet” form that results in cardiac overload and massive edema, or in a “dry” variant — of which WKS is a subset — that affects the peripheral nervous system, the brain, or both. In addition to amnesia, victims of WKS often display striking degrees of spontaneous confabulation, in which they volunteer personal stories that they believe to be true but are not. Prevalence rates for WKS at autopsy have been found to run as high as 2.8 percent in Australia, and between 0.1 to 2.2 percent in the U.S. Copyright 2019 Undark

Keyword: Drug Abuse; Learning & Memory
Link ID: 25923 - Posted: 02.01.2019

By Virginia Morell It’s hard to imagine a teen asking their mother for approval on anything. But a new study shows that male zebra finches—colorful songbirds with complex songs—learn their father’s tune better when mom “fluffs up” to signal her approval. This is the first time the songbirds, thought to be mere memorization machines, have been shown to use social cues for learning—putting them in an elite club that includes cowbirds, marmosets, and humans. The finding suggests other songbirds might also learn their tunes this way, and that zebra finches are better models for studying language development than thought. “Female zebra finches play an important role in male learning, in some ways even rivaling that of the male tutors,” says Karl Berg, an avian ecologist at the University of Texas in Brownsville, who was not involved in the new study. Previously, scientists knew only that the nonsinging females played some role in song acquisition, because males raised with deaf females develop incorrect songs. Researchers have long known that female brown-headed cowbirds make quick, lateral wing strokes to approve the songs of juvenile males (as in finches, only male cowbirds learn to sing). Most scientists discounted the cowbirds’ social cues as an isolated oddity, because the birds are brood parasites. But cowbirds’ similarities to zebra finches—both are highly social and use their songs to attract mates rather than claim territories—led Cornell University developmental psychobiologists Samantha Carouso-Peck and Michael Goldstein to wonder whether female finches also use social cues to help young males learn the best, mate-attracting songs. © 2018 American Association for the Advancement of Science.

Keyword: Animal Communication; Sexual Behavior
Link ID: 25922 - Posted: 02.01.2019

By Roni Caryn Rabin A sudden shortage of one of the safest anti-anxiety drugs on the market has spread alarm among people who rely on the medication, buspirone, to get through the day without debilitating anxiety and panic attacks. Physicians are also expressing concern, because there is no information about when the supply will resume, making it difficult to manage patients. Shelby Vittek, a 27-year-old writer in New Jersey, fruitlessly called dozens of drugstores in New Jersey and Pennsylvania in an attempt to locate the medication after her pharmacist told her the drug was on back-order with no end in sight. She ended up weaning herself off the drug, spreading her last three pills over six days to avoid having to go “cold turkey” before starting a difficult transition to an antidepressant. “I pretty much lost over a month of work, and have just started to feel like myself again,” she said. A 34-year-old New York woman who couldn’t get her buspirone refilled in January said she couldn’t sleep and had such severe panic attacks that she had to use Klonopin, a drug she dislikes because it is addictive. “I’m trying to take care of my anxiety, and it’s giving me a panic attack,” said the woman, a sexual assault survivor who asked not to be identified. A Pennsylvania medical school student received her mail-order shipment of medication last week with no buspirone in it and no explanation, so she scrounged around the house and dug up old pills from missed doses. Last weekend, the student, who asked not to be identified, was so anxious she could not leave the house. “This is potentially messing with people’s clinical stability,” said Dr. Dennis Glick, a psychiatrist in Greenbelt, Md. “When you have a patient with a complicated and balanced regimen, you really don’t want to just arbitrarily have someone come off the medicine.” Dr. Glick said he has been in practice for 34 years “and I honestly don’t recall issues like this interfering with care until maybe a couple of years ago.” © 2019 The New York Times Company

Keyword: Stress; Drug Abuse
Link ID: 25921 - Posted: 02.01.2019

Laura Sanders Do you floss regularly? A study published January 23 in Science Advances — and the news stories that it inspired — might have scared you into better oral hygiene by claiming to find a link between gum bacteria and Alzheimer’s disease. Those experiments hinted that the gum disease–causing bacteria Porphyromonas gingivalis was present in the brains of a small number of people who died with the degenerative brain disease. Some headlines trumpeted that the cause of Alzheimer’s had finally been found. Enzymes made by P. gingivalis, called gingipains, interact with key Alzheimer’s proteins called amyloid-beta and tau in test tube experiments and in the brains of mice, the researchers found. Gingipains prod A-beta to accumulate and tau to behave abnormally, both signs of Alzheimer’s disease in people, the experiments suggest. And compounds that block gingipains seemed to reduce the amount of A-beta in the infected mice. The findings “offer evidence that P. gingivalis and gingipains in the brain play a central role” in the development of Alzheimer’s disease, the researchers write in their study. The research was paid for and conducted in part by employees of Cortexyme, Inc., a San Francisco–based biotech company that’s developing these compounds. The results fit with an idea that’s gaining traction among Alzheimer’s researchers — that bacteria, viruses and even fungi could spark the disease (SN: 7/21/18, p. 10). But the Science Advances study is far from conclusive, cautions Rudolph Tanzi, an Alzheimer’s researcher at Massachusetts General Hospital in Boston. Science News asked him what the study can, and can’t, answer about Alzheimer’s disease. His responses are edited for length and clarity. |© Society for Science & the Public 2000 - 2019

Keyword: Alzheimers
Link ID: 25920 - Posted: 02.01.2019

By Benedict Carey The world’s most common digital habit is not easy to break, even in a fit of moral outrage over the privacy risks and political divisions Facebook has created, or amid concerns about how the habit might affect emotional health. Although four in 10 Facebook users say they have taken long breaks from it, the digital platform keeps growing. A recent study found that the average user would have to be paid $1,000 to $2,000 to be pried away for a year. So what happens if you actually do quit? A new study, the most comprehensive to date, offers a preview. Expect the consequences to be fairly immediate: More in-person time with friends and family. Less political knowledge, but also less partisan fever. A small bump in one’s daily moods and life satisfaction. And, for the average Facebook user, an extra hour a day of downtime. The study, by researchers at Stanford University and New York University, helps clarify the ceaseless debate over Facebook’s influence on the behavior, thinking and politics of its active monthly users, who number some 2.3 billion worldwide. The study was posted recently on the Social Science Research Network, an open access site. “For me, Facebook is one of those compulsive things,” said Aaron Kelly, 23, a college student in Madison, Wis. “It’s really useful, but I always felt like I was wasting time on it, distracting myself from study, using it whenever I got bored.” Mr. Kelly, who estimated that he spent about an hour a day on the platform, took part in the study “because it was kind of nice to have an excuse to deactivate and see what happened,” he said. Well before news broke that Facebook had shared users’ data without consent, scientists and habitual users debated how the platform had changed the experience of daily life. A cadre of psychologists has argued for years that the use of Facebook and other social media is linked to mental distress, especially in adolescents. Others have likened habitual Facebook use to a mental disorder, comparing it to drug addiction and even publishing magnetic-resonance images of what Facebook addiction “looks like in the brain.” © 2019 The New York Times Company

Keyword: Attention; Depression
Link ID: 25919 - Posted: 01.31.2019

By Laurie McGinley E-cigarettes are almost twice as effective at helping smokers quit as nicotine replacement therapies such as lozenges and patches, according to a new study that immediately stoked the debate over whether e-cigarettes are an important smoking-cessation tool or a health menace. The study, published online Wednesday by the New England Journal of Medicine, is the first randomized trial to test the effectiveness of modern e-cigarettes vs. nicotine-replacement products, said Peter Hajek, a psychologist at Queen Mary University of London, who led the trial. The researchers found that 18 percent of the e-cigarette users were smoke-free after a year, compared with 9.9 percent of those in the nicotine-replacement group. The participants also received behavioral support to stop smoking. For years, physicians have been reluctant to recommend e-cigarettes for smoking cessation because of a lack of clinical trial data, Hajek said. “This is now likely to change,” he added in a statement. But two editorials in the same publication threw some cold water on the trial’s results. One editorial, by Boston University researchers, said e-cigarettes should be used only when Food and Drug Administration-approved treatments do not work. Those approved therapies, as well as drugs such as bupropion, have higher effectiveness rates than the new study suggested, and much more is known about their side effects, said Belinda Borrelli, a Boston University researcher who co-wrote the editorial. © 1996-2019 The Washington Post

Keyword: Drug Abuse
Link ID: 25918 - Posted: 01.31.2019