By Wallis Snowdon, Ariel Fournier The seizure of a controversial drug in Edmonton is evidence that more research is required on kratom as a possible antidote in Alberta's deadly opioid epidemic, says a leading researcher in the field. "Everything has to be taken with caution, but does that mean you take it off the streets?" said Susruta Majumdar, a chemist who has worked on numerous studies into the drug. "Probably not," said Majumdar, who works in the department of neurology at Sloan Kettering Cancer Center in New York. "It's a little premature to ban it right away and take it out of the public scenario because very little research has been done. It's a weak alkaloid but we need to be cautious about it." In a news release Tuesday, Health Canada said it had seized unauthorized kratom products from two Edmonton head shops. The packets were confiscated from a store called Jupiter on Whyte Avenue and from another called Bogart's Pipes and Papers on 132nd Avenue. Kratom is a coffee-like plant native to southeast Asia. The drug is traditionally consumed by chewing on the leaves, but can also be ingested as a capsule or powder or as a tea. Health Canada said the herbal product has been linked to both "narcotic and stimulant-like effects," and may pose serious health risks including nausea, vomiting, seizures, and liver toxicity. ©2017 CBC/Radio-Canada.

Keyword: Drug Abuse
Link ID: 23799 - Posted: 07.01.2017

ByMaia Szalavitz George Sarlo is throwing cash at research into how drugs like magic mushrooms can help people overcome trauma like his own. Deep in the Mexican jungle, in a village so remote it's only accessible by boat, 74-year-old venture capitalist George Sarlo waited to meet his father. It was the fall of 2012, and Sarlo knew his quest seemed absurd. After all, his father had been dead for decades, and he had no connection to this region of rainforests and beaches and its indigenous peoples. As the financier watched a shaman prepare a ceremonial cup of bitter brown ayahuasca, he couldn't believe that he'd agreed to swallow this nauseating psychedelic brew for a second time. But he had traveled for 12 hours—via plane, boat, and finally on foot—to this primeval place, a newly-built gazebo-like wood platform without walls. He had expressed his intentions in a group therapy session in preparation; he had eaten a special, bland diet and even halted other medications. He also trusted his friend, Dr. Gabor Maté, a fellow Hungarian Holocaust survivor, who led the therapy and had arranged the trip. Maté is perhaps best known for his book, In the Realm of Hungry Ghosts, which explores his work with extremely traumatized injection drug users in Vancouver. He's been offering psychedelic therapy to trauma survivors since learning about the potential of ayahuasca in 2008.

Keyword: Drug Abuse; Stress
Link ID: 23798 - Posted: 07.01.2017

Hannah Devlin Doctors in Bristol are set to begin the world’s first clinical study into the use of MDMA to treat alcohol addiction. Researchers are testing whether a few doses of the drug, in conjunction with psychotherapy, could help patients overcome addiction more effectively than conventional treatments. The small trial was granted ethical approval a few weeks ago and the team expects to give the first dose of MDMA, the active ingredient in ecstasy pills, within the next two months. Ben Sessa, a clinical psychiatrist on the trial and senior research fellow at Imperial College London said: “We know that MDMA works really well in helping people who have suffered trauma and it helps to build empathy. Many of my patients who are alcoholics have suffered some sort of trauma in their past and this plays a role in their addiction.” Twenty patients, recruited through the recreational drug and alcohol services in Bristol, will be given the drug in capsule form during two supervised treatment sessions. The participants will be heavy drinkers – typically consuming the equivalent of five bottles of wine a day – who have relapsed into alcoholism repeatedly after trying other forms of treatment. “After 100 years of modern psychiatry our treatments are really poor,” said Sessa, speaking at the Breaking Convention conference in London. “The chances of relapse for these patients are really high – 90% at three years. No one has ever given MDMA to treat alcoholism before.” © 2017 Guardian News and Media Limited

Keyword: Drug Abuse
Link ID: 23797 - Posted: 07.01.2017

By ABBY GOODNOUGH WASHINGTON — The Senate leadership’s efforts to salvage the Republican health care bill have focused in part on adding $45 billion for states to spend on opioid addiction treatment. That is a big pot of money. But addiction specialists said it was drastically short of what would be needed to make up for the legislation’s deep cuts to Medicaid, which has provided treatment for hundreds of thousands of people caught up in a national epidemic of opioid abuse. The new money would most likely flow to states in the form of grants over 10 years, averaging out to $4.5 billion per year. With hundreds of people dying every week from overdoses of heroin, fentanyl and opioid painkillers, some specialists say a fixed amount of grant money is simply inadequate compared with the open-ended funding stream that Medicaid provides to treat all who qualify for the coverage. “When it comes to other illnesses like breast cancer or heart disease, we’d never rely solely on grants for treatment — because we know that grants are not substitutes for health coverage,” said Linda Rosenberg, president and chief executive of the National Council for Behavioral Health, which represents treatment providers. “Addiction is no different.” The Affordable Care Act vastly expanded access to addiction treatment by designating those services as “essential benefits.” That means they had to be covered through both an expansion of Medicaid to far more low-income adults and the marketplaces set up under the law for people to buy private plans. Both the House and Senate health bills would effectively end the expansion and cap federal Medicaid spending, resulting in the loss of coverage for millions of people, according to the Congressional Budget Office. © 2017 The New York Times Company

Keyword: Drug Abuse
Link ID: 23796 - Posted: 07.01.2017

Martha Mills So, it turns out I’m getting better at depression. That isn’t to say I’ve stopped suffering it, or that it is any less debilitating when it sneaks up after a two-year hiatus and pile-drives me into a blistering agony of mental carpet burns topped with a patronising tousle of the bed-hair, like a nostalgic school bully. No, what’s “better” about me is spotting it and moving quicker through the self-blame method of diagnosis. We all have down days, and that’s what you hope these are. Only they stopped being a day or two of feeling blue that can be whiled away with the distraction of a conspiratorial sofa and questionable DVD collection, and have merged into weeks since you were last able to feel anything but disappointment on waking up, and the choice between showering or just smelling like a tramp’s undercarriage has gone beyond struggle into pure resignation. Being especially practised at denial, I decided that I, a mere mortal with a solid history of depressive episodes since childhood, could fake my way out of this oncoming tsunami of debilitating black fog using the advice that people who have never experienced depression trot out – an experiment that could surely only succeed [sidelong glance to camera]. I would improve my diet and exercise, force myself to take up hobbies, I would “soldier on until it passed” and thrust myself (reluctantly) into social situations. I even tried “looking on the bright side” but it turned out to just be glare on my TV. © 2017 Guardian News and Media Limited

Keyword: Depression
Link ID: 23795 - Posted: 07.01.2017

By Nicholette Zeliadt Researchers have known that genes contribute to autism since the 1970s, when a team found that identical twins often share the condition. Since then, scientists have been racking up potential genetic culprits in autism, a process that DNA-decoding technologies have accelerated in the past decade. As this work has progressed, scientists have unearthed a variety of types of genetic changes that can underlie autism. The more scientists dig into DNA, the more intricate its contribution to autism seems to be. How do researchers know genes contribute to autism? Since the first autism twin study in 1977, several teams have compared autism rates in twins and shown that autism is highly heritable. When one identical twin has autism, there is about an 80 percent chance that the other twin has it, too. The corresponding rate for fraternal twins is around 40 percent. However, genetics clearly does not account for all autism risk. Environmental factors also contribute to the condition, although researchers disagree on the relative contributions of genes and environment. Some environmental risk factors for autism, such as exposure to a maternal immune response in the womb or complications during birth, may work with genetic factors to produce autism or intensify its features. Is there such a thing as an autism gene? Not really. There are several conditions associated with autism that stem from mutations in a single gene, including fragile X and Rett syndromes. But less than 1 percent of non-syndromic cases of autism stem from mutations in any single gene. © 1996-2017 The Washington Post

Keyword: Autism; Genes & Behavior
Link ID: 23794 - Posted: 07.01.2017

By Mo Costandi You can’t teach an old dog new tricks—or can you? Textbooks tell us that early infancy offers a narrow window of opportunity during which sensory experience shapes the way neuronal circuits wire up to process sound and other inputs. A lack of proper stimulation during this “critical period” has a permanent and detrimental effect on brain development. But new research shows the auditory system in the adult mouse brain can be induced to revert to an immature state similar to that in early infancy, improving the animals’ ability to learn new sounds. The findings, published Thursday in Science, suggest potential new ways of restoring brain function in human patients with neurological diseases—and of improving adults’ ability to learn languages and musical instruments. In mice, a critical period occurs during which neurons in a portion of the brain’s wrinkled outer surface, the cortex, are highly sensitized to processing sound. This state of plasticity allows them to strengthen certain connections within brain circuits, fine-tuning their auditory responses and enhancing their ability to discriminate between different tones. In humans, a comparable critical period may mark the beginning of language acquisition. But heightened plasticity declines rapidly, and this continues throughout life, making it increasingly difficult to learn. In 2011 Jay Blundon, a developmental neurobiologist at Saint Jude Children's Research Hospital, and his colleagues reported that the critical periods for circuits connecting the auditory cortex and the thalamus occur at about the same time. © 2017 Scientific American,

Keyword: Hearing; Development of the Brain
Link ID: 23793 - Posted: 06.30.2017

By Kathryn Casteel It’s no secret that heroin has become an epidemic in the United States. Heroin overdose deaths have risen more than sixfold in less than a decade and a half.1 Yet according to one of the most widely cited sources of data on drug use, the number of Americans using heroin has risen far more slowly, roughly doubling during the same time period.2 Most major researchers believe that source, the National Survey on Drug Use and Health, vastly understates the increase in heroin use. But many rely on the survey anyway for a simple reason: It’s the best data they have. Several other sources that researchers once relied on are no longer being updated or have become more difficult to access. The lack of data means researchers, policymakers and public health workers are facing the worst U.S. drug epidemic in a generation without essential information about the nature of the problem or its scale. “We’re simply flying blind when it comes to data collection, and it’s costing lives,” said John Carnevale, a drug policy expert who served at the federal Office of National Drug Control Policy under both Republican and Democratic administrations. There is anecdotal evidence of how patterns of drug use are changing, Carnevale said, and special studies conducted in various localities are identifying populations of drug users. “But the national data sets we have in place now really don’t give us the answers that we need,” he said.

Keyword: Drug Abuse
Link ID: 23792 - Posted: 06.30.2017

By Diana Kwon By blocking specific enzymes, researchers were able to selectively remove memories stored in the neurons of Aplysia, a sea slug. These findings, published last week (June 22) in Current Biology, demonstrate that distinct memories stored in connections to a single nerve cell can be manipulated separately. “We were able to reverse long-term changes in synaptic strength at synapses known to contribute to different forms of memories,” study coauthor Samuel Schacher, a neuroscientist at Columbia University, told Motherboard. By stimulating multiple Aplysia sensory neurons that make connections with to the same motor neuron, Schacher and colleagues induced associative memory, which involves learning the relationship between two previously unrelated items (a new acquaintance’s name, for example), and non-associative memory, where recollections are unrelated to a specific event. The team measured the strength of the synaptic connections between the sensory and motor neurons and discovered that distinct forms of an enzyme, protein kinase M (PKM), played a role in developing the changes linked to the two types of memory. Selectively blocking these molecules, the researchers found, allowed them to remove the memories of their choice. Molecules associated with memory have been discovered in the past. For example, in a 2006 Science study, another team of researchers was able to erase memories in mice by blocking a related molecule, PKM-zeta. Subsequent papers, however, found that mice lacking this enzyme had no problem forming memories. © 1986-2017 The Scientist

Keyword: Learning & Memory
Link ID: 23791 - Posted: 06.30.2017

By STEPH YIN Whales and songbirds produce sounds resembling human music, and chimpanzees and crows use tools. But only one nonhuman animal is known to marry these two skills. Palm cockatoos from northern Australia modify sticks and pods and use them to drum regular rhythms, according to new research published in Science Advances on Wednesday. In most cases, males drop beats in the presence of females, suggesting they perform the skill to show off to mates. The birds even have their own signature cadences, not unlike human musicians. This example is “the closest we have so far to musical instrument use and rhythm in humans,” said Robert Heinsohn, a professor of evolutionary and conservation biology at the Australian National University and an author of the paper. A palm cockatoo drumming performance starts with instrument fashioning — an opportunity to show off beak strength and cleverness (the birds are incredibly intelligent). Often, as a female is watching, a male will ostentatiously break a hefty stick off a tree and trim it to about the length of a pencil. Holding the stick, or occasionally a hard seedpod, with his left foot (parrots are typically left-footed), the male taps a beat on his tree perch. Occasionally he mixes in a whistle or other sounds from an impressive repertoire of around 20 syllables. As he grows more aroused, the crest feathers on his head become erect. Spreading his wings, he pirouettes and bobs his head deeply, like an expressive pianist. He uncovers his red cheek patches — the only swaths of color on his otherwise black body — and they fill with blood, brightening like a blush. Over seven years, Dr. Heinsohn and his collaborators collected audio and video recordings of 18 male palm cockatoos exhibiting such behaviors in Australia’s Cape York Peninsula, where the birds are considered vulnerable because of aluminum ore mining. © 2017 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 23790 - Posted: 06.29.2017

Nicola Davis If you want your smile to appear pleasant, you might want to avoid a dazzling beam, research suggests. A study by scientists in the US has found that wide smiles with a high angle and showing a lot of teeth are not the best at creating a positive impression. “A lot of people don’t understand how important their smiles are and how important this aspect of communication we do with each other every day is,” said Stephen Guy, a co-author of the research from the University of Minnesota. The authors say the findings could prove valuable for clinicians working to restore facial movement and expression to those who have experienced facial paralysis. “When you have different surgical options, how do you choose which one is better?” Guy said, pointing out that some options might offer more extent of smile – referring to breadth – but others might improve the angle. “In order to do that, you need to say, ‘Oh, this smile is better or worse than that smile.’” To find the perfect smile, the team showed a 3D, computer-animated virtual face smiling in a range of different ways to 802 members of the public, ranging in age from 18 to 82. All had consumed fewer than six alcoholic drinks – the study was carried out at the Minnesota state fair. Each animation ran for 250 milliseconds and the faces showed differences in the angle of the smile, how broad it was, and the amount that teeth on show. In addition, the team took one smile – featuring a high angle, low extent and medium amount of dental show – and tinkered with the symmetry of the smile, changing the length of time it took the left side of the face to smile compared with the right. © 2017 Guardian News and Media Limited

Keyword: Emotions
Link ID: 23789 - Posted: 06.29.2017

By Dina Fine Maron Not all of Mitchell Elkind’s stroke patients are on social security. In recent years he has treated devastating attacks in people as young as 18. And he is not alone. A growing body of research indicates strokes among U.S. millennials—ages 18 to 34—have soared in recent years. But an analysis by Scientific American has revealed significant differences in where these strokes are occurring, depending both on region and whether people live in rural or urban settings. The investigation, which used data from the U.S. Department of Health and Human Services’ Agency for Healthcare Research and Quality (AHRQ), was reviewed by five stroke experts and found that the West and Midwest have seen especially worrisome increases among younger adults. Moreover, large cities appear to have seen bigger increases than rural areas. The analysis employed hospital discharge data from 2003 to 2012 from the AHRQ’s Healthcare Cost and Utilization Project (HCUP) database. The findings align with earlier studies that pointed to nationwide increases in strokes in this age group: In a study published earlier this year in JAMA Neurology, researchers at the U.S. Centers for Disease Control and Prevention concluded that in a nine-year span from 2003 to 2012 there was a 32 percent spike in strokes among 18- to 34-year-old women and a 15 percent increase for men in the same range. Scientific American’s analysis sought to dig deeper into the data by exploring whether the stroke trend differed by location. © 2017 Scientific American

Keyword: Stroke
Link ID: 23788 - Posted: 06.29.2017

By Kerry Grens Until a little more than a decade ago, doctors had few options to treat newborns whose brains were deprived of oxygen or blood at birth, a condition known as perinatal hypoxic-ischemic encephalopathy, or HIE. If babies could be stabilized and kept breathing, physicians and nurses could offer only supportive care and had to watch and wait to see how much brain damage their patients would suffer. “This was a disease where we had no treatment that worked, and [around] 60 percent of these babies were either dying or had a disability,” says Rosemary Higgins, a program scientist at the National Institute of Child Health and Human Development. In 2005, research findings reshaped the field. Higgins and other neonatologists reported the results of a couple of large clinical trials testing the effects of so-called cooling therapy on brain damage. Hundreds of babies suffering from HIE—the effects on the brain of oxygen deprivation during delivery, due to umbilical cord problems, the placenta coming away from the uterus too soon, or other complications—had their temperatures chilled from roughly 37 °C to about 33 °C for 72 hours, then slowly rewarmed (in one study it was whole-body cooling, in the other it was just the head). Although many babies still died of the brain damage or ended up with a severe disability, more fared better in the treatment groups than in the control groups (New Engl J Med, 353:1574-84; The Lancet, 365:663-70). “Cooling was a landmark discovery for this disease,” Higgins says. Finally, doctors (and their patients) weren’t completely helpless. The intervention used in these studies reduced the number of newborns dying or enduring a severe disability to below 50 percent. © 1986-2017 The Scientist

Keyword: Sleep; Development of the Brain
Link ID: 23787 - Posted: 06.29.2017

People with higher IQs are less likely to die before the age of 79. That’s according to a study of over 65,000 people born in Scotland in 1936. Each of the people in the study took an intelligence test at the age of 11, and their health was then followed for 68 years, until the end of 2015. When Ian Deary, of the University of Edinburgh, UK, and his team analysed data from the study, they found that a higher test score in childhood was linked to a 28 per cent lower risk of death from respiratory disease, a 25 per cent reduced risk of coronary heart disease, and a 24 per cent lower risk of death from stroke. These people were also less likely to die from injuries, digestive diseases, and dementia – even when factors like socio-economic status were taken into account. Deary’s team say there are several theories for why more intelligent people live longer, such as people with higher IQs being more likely to look after their health and less likely to smoke. They also tend to do more exercise and seek medical attention when ill. “I’m hoping it means that if we can find out what smart people do and copy them, then we have a chance of a slightly longer and healthier life,” says Dreary. But there’s evidence genetics is involved too. A recent study suggests that very rare genetic variants can play an important role in lowering intelligence, and that these may also be likely to impair a person’s health. Journal reference: British Medical Journal, DOI: 10.1136/bmj.j2708 © Copyright New Scientist Ltd.

Keyword: Intelligence
Link ID: 23786 - Posted: 06.29.2017

By Anil Ananthaswamy To understand human consciousness, we need to know why it exists in the first place. New experimental evidence suggests it may have evolved to help us learn and adapt to changing circumstances far more rapidly and effectively. We used to think consciousness was a uniquely human trait, but neuroscientists now believe we share it with many other animals, including mammals, birds and octopuses. While plants and arguably some animals like jellyfish seem able to respond to the world around them without any conscious awareness, many other animals consciously experience and perceive their environment. Read more: Why be conscious – The improbable origins of our unique mind In the 19th century, Thomas Henry Huxley and others argued that such consciousness is an “epiphenomenon” – a side effect of the workings of the brain that has no causal influence, the way a steam whistle has no effect on the way a steam engine works. More recently, neuroscientists have suggested that consciousness enables us to integrate information from different senses or keep such information active for long enough in the brain that we can experience the sight and sound of car passing by, for example, as one unified perception, even though sound and light travel at different speeds. © Copyright New Scientist Ltd.

Keyword: Consciousness; Learning & Memory
Link ID: 23785 - Posted: 06.28.2017

By Meredith Wadman The hallmark brain damage in Parkinson’s disease is thought to be the work of a misfolded, rogue protein that spreads from brain cell to brain cell like an infection. Now, researchers have found that the normal form of the protein—α-synuclein (αS)—may actually defend the intestines against invaders by marshaling key immune cells. But chronic intestinal infections could ultimately cause Parkinson’s, the scientists suggest, if αS migrates from overloaded nerves in the gut wall to the brain. “The gut-brain immune axis seems to be on a cusp of an explosion of new insights, and this work offers an exceptionally exciting new hypothesis,” says Charles Bevins, an expert in intestinal immunity at the University of California, Davis, who was not involved with the study. The normal function of αS has long been a mystery. Though the protein is known to accumulate in toxic clumps in the brain and the nerves of the gut wall in patients with Parkinson’s disease, no one was sure what it did in healthy people. Noting that a region of the αS molecule behaves similarly to small, microbe-targeting proteins that are part of the body’s immune defenses, Michael Zasloff, an immunologist at Georgetown University Medical Center in Washington, D.C., set out to find whether αS, too, might help fend off microbial invaders. © 2017 American Association for the Advancement of Science

Keyword: Parkinsons
Link ID: 23784 - Posted: 06.28.2017

By Debra W. Soh If there was a way of telling who in our society is sexually attracted to children, are we entitled to know? A recent study from Georg-August-University Göttingen in Germany suggests that we may need to grapple with this question. Phallometric testing, also known as penile plethysmography, is considered the gold standard in measuring male sexual arousal, and particularly, deviant sexual interests such as pedophilia, which is the sexual interest in prepubescent children, roughly aged 3 to 10. The test involves measuring the volume of blood in the test-taker’s penis using an airtight glass tube (or conversely, measuring penile circumference with a mercury strain gauge) while he is presented with a series of images of children and adults, and audio stories describing a corresponding sexual encounter. Phallometry is commonly used in forensic settings to assess the sexual interests of sex offenders, in order to determine their risk of re-offending. As one can imagine, sex offenders tend not to be forthright about their sexual preferences, which makes phallometry all the more important. It has, however, been criticized because the test can become easier for individuals to fool with each successive assessment. Brain scanning using fMRI holds much promise as a diagnostic tool in evaluating sexual interests, as research has documented a reliable network of brain regions involved in sexual arousal. The current study took this another step by testing whether brain functional activation could be used to infer what someone finds sexually interesting without them knowing. © 2017 Scientific American,

Keyword: Sexual Behavior; Brain imaging
Link ID: 23783 - Posted: 06.28.2017

By Michael Price Contrary to popular lore that portrays chimpanzees as having “super strength,” studies have only found modest differences with humans. But our closest relatives are slightly stronger by several measures, and now a study comparing the muscle fibers of different primates reveals a potential explanation: Humans may have traded strength for endurance, allowing us to travel farther for food. To determine why chimpanzees are stronger than humans—at least on a pound-for-pound basis—Matthew O’Neill, an anatomy and evolution researcher at the University of Arizona College of Medicine in Phoenix, and colleagues biopsied the thigh and calf muscles of three chimps housed at the State University of New York at Stony Brook. They dissected the samples into individual fibers and stimulated them to figure out how much force they could generate. Comparing their measurements to known data from humans, the team found that, at the individual fiber level, muscle output was about the same. Given that different fibers throughout the muscle might make a difference, the researchers conducted a more thorough analysis of tissue samples from pelvic and hind limb muscles of three chimpanzee cadavers from various zoos and research institutes around the United States. Previous studies in mammals have found that muscle composition between trunk, forelimb, and hind limb muscles is largely the same, O’Neill says, so he’s confident the samples are representative across most of the chimp’s musculature. The team used a technique called gel electrophoresis to break down the muscles into individual muscle fibers, and compared this breakdown to human muscle fiber data. © 2017 American Association for the Advancement of Science.

Keyword: Muscles; Evolution
Link ID: 23782 - Posted: 06.27.2017

Carl Zimmer Mark D. Zabel wants to set some fires. Dr. Zabel and his colleagues are developing plans to burn plots of National Park Service land in Arkansas and Colorado. If the experiments turn out as the researchers hope, they will spare some elk and deer a gruesome death. Across a growing swath of North America, these animals are dying from a mysterious disorder called chronic wasting disease. It’s caused not by a virus or bacterium, but a deformed protein called a prion. When ingested, prions force normal proteins in the animal’s body to become deformed as well. Over the course of months, prions can gradually wreck the animal’s nervous system, ultimately killing it. This year is the 50th anniversary of the discovery of chronic wasting disease. In the September issue of Microbiology and Molecular Biology Reviews, Dr. Zabel, an immunologist at Colorado State University, and his former graduate student Aimee Ortega survey what scientists have learned about the slow-spreading plague. It makes for ominous reading. “There’s a lot that we still don’t know and don’t understand about the disease,” Dr. Zabel said in an interview. Once chronic wasting disease gets a foothold, it can spread relentlessly. It’s now documented in 24 states, and continues to expand into new ranges. In some herds, as many as half of the animals carry prions. It’s only been in recent years that scientists have gained crucial clues to how the disease spreads. Direct contact, it turns out, isn’t the only way that the prions get from one animal to another. © 2017 The New York Times Company

Keyword: Prions
Link ID: 23781 - Posted: 06.27.2017

By Alice Klein Women are missing out on optimum medical treatment because most pre-clinical drug research is done in male animals, a new study suggests. New drugs must be evaluated in animals before being considered for human trials. Over three-quarters of these studies use only male animals because of concerns that female hormone cycles will affect experiments. It is also widely assumed that what works for males will work for females. However, research by Natasha Karp at the Wellcome Trust Sanger Institute in Cambridge and her colleagues casts doubt on this assumption. They compared 234 physical traits in 14,000 male and female lab mice. Sex differences were identified for 57 per cent of quantifiable traits – like cholesterol level and bone mass – and for 10 per cent of qualitative traits, like head shape. In another 40,000 mice, they found that when they switched off specific genes, the effects varied according to sex. This suggests that genetic diseases may manifest themselves differently in males and females and require different treatments, says Karp. These sex nuances mean that drugs optimised for male animals may be less effective in females, or even cause harm, says Karp. Between 1997 and 2001, 8 of the 10 drugs that were pulled from the market in the US posed greater health risks for women – possibly as a result of male-biased animal research, she says. © Copyright New Scientist Ltd.

Keyword: Sexual Behavior
Link ID: 23780 - Posted: 06.27.2017