by Jessica Hamzelou California has become the first US state to ban unfounded therapies that attempt to turn gay teenagers straight. "These practices have no basis in science or medicine and they will now be relegated to the dustbin of quackery," said state governor Jerry Brown in a statement to the San Francisco Chronicle. He signed a bill outlawing the therapies on 29 September. Brown's conclusions are in line with those reached a few years ago by a task force of psychologists who were commissioned by the American Psychological Association to assess all published research on the therapies. The group, led by Judith Glassgold, found no evidence that the treatment was effective. "The scientific evidence does not support such therapies," says Clinton Anderson, director of the APA's Lesbian, Gay, Bisexual and Transgender Concerns office. "They were not helpful and could be harmful," says Glassgold, who is based in Washington DC. "Most people became more depressed and anxious, and could become suicidal." "Usually these talk therapies are based on the assumption that homosexuality is a mental illness caused by poor parenting and confused gender roles," she adds. "They attempt to explain that to the patient, and try to get them to act and behave in a heterosexual manner." © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior
Link ID: 17316 - Posted: 10.02.2012

by Melissa Lee Phillips  Giving a whole new meaning to "pregnancy brain," a new study shows that male DNA—likely left over from pregnancy with a male fetus—can persist in a woman's brain throughout her life. Although the biological impact of this foreign DNA is unclear, the study also found that women with more male DNA in their brains were less likely to have suffered from Alzheimer's disease—hinting that the male DNA could help protect the mothers from the disease, the researchers say. During mammalian pregnancy, the mother and fetus exchange DNA and cells. Previous work has shown that fetal cells can linger in the mother's blood and bone for decades, a condition researchers call fetal microchimerism. The lingering of the fetal DNA, research suggests, may be a mixed blessing for a mom: The cells may benefit the mother's health—by promoting tissue repair and improving the immune system—but may also cause adverse effects, such as autoimmune reactions. One question is how leftover fetal cells affect the brain. Researchers have shown that fetal microchimerism occurs in mouse brains, but they had not shown this in humans. So a team led by autoimmunity researcher and rheumatologist J. Lee Nelson of the Fred Hutchinson Cancer Research Center in Seattle, Washington, took samples from autopsied brains of 59 women who died between the ages of 32 and 101. By testing for a gene specific to the Y chromosome, they found evidence of male DNA in the brains of 63% of the women. (The researchers did not have the history of the women's pregnancies.) The male DNA was scattered across multiple brain regions, the team reports online today in PLoS ONE. Because some studies have suggested that the risk of Alzheimer's disease (AD) increases with an increasing number of pregnancies, the team also examined the brains for signs of the disease, allowing them to determine whether AD correlated with the observed microchimerism. Of the 59 women, 33 had AD—but contrary to the team's expectation, the women with AD had significantly less male DNA in their brains than did the 26 women who did not have AD. © 2010 American Association for the Advancement of Science

Keyword: Sexual Behavior; Aggression
Link ID: 17314 - Posted: 09.29.2012

by Melissa Lee Phillips Giving a whole new meaning to "pregnancy brain," a new study shows that male DNA—likely left over from pregnancy with a male fetus—can persist in a woman's brain throughout her life. Although the biological impact of this foreign DNA is unclear, the study also found that women with more male DNA in their brains were less likely to have suffered from Alzheimer's disease—hinting that the male DNA could help protect the mothers from the disease, the researchers say. During mammalian pregnancy, the mother and fetus exchange DNA and cells. Previous work has shown that fetal cells can linger in the mother's blood and bone for decades, a condition researchers call fetal microchimerism. The lingering of the fetal DNA, research suggests, may be a mixed blessing for a mom: The cells may benefit the mother's health—by promoting tissue repair and improving the immune system—but may also cause adverse effects, such as autoimmune reactions. One question is how leftover fetal cells affect the brain. Researchers have shown that fetal microchimerism occurs in mouse brains, but they had not shown this in humans. So a team led by autoimmunity researcher and rheumatologist J. Lee Nelson of the Fred Hutchinson Cancer Research Center in Seattle, Washington, took samples from autopsied brains of 59 women who died between the ages of 32 and 101. By testing for a gene specific to the Y chromosome, they found evidence of male DNA in the brains of 63% of the women. (The researchers did not have the history of the women's pregnancies.) The male DNA was scattered across multiple brain regions, the team reports online today in PLoS ONE. © 2010 American Association for the Advancement of Science

Keyword: Development of the Brain; Aggression
Link ID: 17310 - Posted: 09.27.2012

by Gisela Telis In the industrialized world, women live at least 5 years longer, on average, than men. Scientists have attributed that difference to everything from healthier habits to hardier cells. Now, a new study that analyzes the longevity of eunuchs, or castrated men, suggests that testosterone may play a part in shortening men's lives. The idea that testosterone, the male sex hormone, affects lifespan isn't new. Neutered dogs and other animals that have had their sources of testosterone removed often live longer than their intact counterparts. But studies on the connection between castration and longevity in humans are harder to come by, and the results have been inconclusive. A 1969 study of institutionalized patients in Kansas found that castrated men lived an average of 14 years longer than other men in the same facility, but a 1993 study of Italian castrati (singers castrated as boys to preserve their high voices) found nothing unusual about their longevity. Almost 5 years ago, biologist Kyung-Jin Min of Inha University in Incheon, Korea, found himself considering this lack of data while watching a Korean TV drama about eunuchs. Min began to wonder if Korea's rich historical records could shed light on the link between castration and longevity in humans. Until the late 19th century, Korean rulers employed eunuchs to serve the royal court. These eunuchs were allowed to marry and adopt castrated boys as their sons. The Yang-Se-Gye-Bo, a genealogical record of the eunuch families, has survived, and it documents the birth and death dates and other personal details of 385 eunuchs who lived between the mid-16th century and the mid-19th century. © 2010 American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Aggression
Link ID: 17298 - Posted: 09.25.2012

By Ilana Yurkiewicz It’s tough to prove gender bias. In a real-world setting, typically the most we can do is identify differences in outcome. A man is selected for hire over a woman; fewer women reach tenure track positions; there’s a gender gap in publications. Bias may be suspected in some cases, but the difficulty in using outcomes to prove it is that the differences could be due to many potential factors. We can speculate: perhaps women are less interested in the field. Perhaps women make lifestyle choices that lead them away from leadership positions. In a real-world setting, when any number of variables can contribute to an outcome, it’s essentially impossible to tease them apart and pinpoint what is causative. The only way to do that would be by a randomized controlled experiment. This means creating a situation where all variables other than the one of interest are held equal, so that differences in outcome can indeed be attributed to the one factor that differs. If it’s gender bias we are interested in, that would mean comparing reactions toward two identical human beings – identical in intelligence, competence, lifestyle, goals, etc. – with the one difference between them that one is a man and one is a woman. Not exactly a situation that exists in the real world. But in a groundbreaking study published in PNAS last week by Corinne Moss-Racusin and colleagues, that is exactly what was done. On Wednesday, Sean Carroll blogged about and brought to light the research from Yale that had scientists presented with application materials from a student applying for a lab manager position and who intended to go on to graduate school. Half the scientists were given the application with a male name attached, and half were given the exact same application with a female name attached. Results found that the “female” applicants were rated significantly lower than the “males” in competence, hireability, and whether the scientist would be willing to mentor the student. © 2012 Scientific American,

Keyword: Sexual Behavior
Link ID: 17294 - Posted: 09.25.2012

By Susan Milius Male killer whale thirtysomethings appear to live longer when mom’s nearby, especially if mom has stopped reproducing. This survival bonus for mama’s boys could be the first evidence from nonhuman animals for an evolutionary advantage to living long after reproduction stops. In the Pacific Northwest, a male killer whale’s risk of disappearing, presumably from dying, seems to jump almost 14-fold if he’s older than 30 and his post-reproductive mom dies, says marine biologist Emma Foster of the University of Exeter in England. Daughters get a more modest fivefold boost, Foster and her colleagues report in the Sept. 14 Science. Both sons and daughters typically spend their lives swimming with mom and other maternal relatives. Even though a female killer whale may stop having babies in her 30s or 40s, she can live into her 90s. Males typically don’t live as long, but they can keep siring offspring throughout their lives. Keeping sons alive as long as possible should therefore maximize the chances that the mom’s genes will be carried into further generations. So, Foster says, the whale survival boost may help explain how female killer whales have evolved the longest post-reproductive life span known among nonhuman animals. “Menopause is still one of the great mysteries of biology,” Foster says. Evolution works as genes for traits multiply through greater numbers of offspring, so what drives the evolution of a no-babies phase of adulthood has been a puzzle. Some theorists have argued that this post-reproductive life span is just a side effect of other survival-boosting traits, but other biologists have searched for some benefit in staying alive post-baby-bearing. The evidence is “quite heavily debated,” as Foster puts it. © Society for Science & the Public 2000 - 2012

Keyword: Sexual Behavior; Aggression
Link ID: 17261 - Posted: 09.15.2012

By Judy Stone In one sense, it is refreshing to see men being the target of pharma, after all these years of women being the focus of relentless—and misleading—advertising. On the other, we’re seeing the start of yet another pharma campaign to dupe the public by the unnecessary medicalization of symptoms to create new drug markets. I used to be a fairly enthusiastic pharma fan, but over recent years have become increasingly disillusioned. The hype over testosterone is the latest example of why. With so many pressing problems in the world, I wish pharma would focus their attention on doing something more useful with their energies. I thought it started with drugs for “hot flashes,” but Karen Roush set me straight about hormone therapy, reporting that “It all started with men in ancient civilizations eating the penis and testicles of animals as a cure for impotence.” (And to think that Maryn McKenna just warned us of the dangers of kissing cats! This early hormone therapy sounds a bit dicier.) In the 1940s, estrogen was able to be extracted from horse urine in large quantities, enabling a supply for treating women “suffering from estrogen deficiency.” Dr. Robert Wilson, a prominent New York gynecologist, founded a private trust in 1963 to promote estrogen use. Pharmaceutical companies provided $1.3 million to this “trust;” they, of course, stood to profit handsomely from their investment in Wilson’s endeavor. Wilson is described as being “evangelical” in his crusade to save women from the “decay” of menopause. He was quite successful, with his 1966 book, Feminine Forever, selling 100,000 copies in the first seven months alone. His theme, “A Plea for the Maintenance of Adequate Estrogen from Puberty to Grave,” expounded in a mainstream medical journal, was adopted both by the medical profession and by the popular press. © 2012 Scientific American

Keyword: Hormones & Behavior; Aggression
Link ID: 17258 - Posted: 09.15.2012

Excerpted from The Chemistry Between Us: Love, Sex and the Science of Attraction, by Larry Young, PhD, and Brian Alexander, by arrangement with Current, a member of Penguin Group (USA), Inc., Copyright © Larry J. Young and Brian Alexander, 2012. To investigate the rodent version of getting hugs, and what happens in the absence of hugs from a bonded partner, Bosch took virgin males and set them up in vole apartments with roommates—either a brother they hadn't seen in a long time or an unfamiliar virgin female. As males and females are wont to do, the boy-girl roommates mated and formed a bond. After five days, he split up half the brother pairs, and half the male-female pairs, creating what amounted to involuntary vole divorce. Then he put the voles through a series of behavioral tests. The first is called the forced-swim test. Bosch likens it to an old Bavarian proverb about two mice who fall into a bucket of milk. One mouse does nothing and drowns. The other tries to swim so furiously the milk turns into butter and the mouse escapes. Paddling is typically what rodents will do if they find themselves in water; they'll swim like crazy because they think they'll drown if they don't. (Actually, they'll float but apparently no rodent floaters have ever returned to fill in the rest of the tribe.) The voles that were separated from their brothers paddled manically. So did the voles who stayed with their brothers and the voles who stayed with their female mates. Only the males who'd gone through vole divorce floated listlessly as if they didn't care whether they drowned. "It was amazing," Bosch recalls. "For minutes, they would just float. You can watch the video and without knowing which group they were in, you can easily tell if it's an animal separated from their partner, or still with their partner." Watching the videos of them bob limply, it's easy to imagine them moaning out "Ain't No Sunshine When She's Gone" with their tiny vole voices. © 2012 Scientific American,

Keyword: Sexual Behavior
Link ID: 17257 - Posted: 09.15.2012

By GRETCHEN REYNOLDS It’s widely accepted among scientists that regular exercise transforms the brain, improving the ability to remember and think. And a growing and very appealing body of science has established that exercise spurs the creation of new brain cells, a process known as neurogenesis. But just how jogging or other workouts affect the structure of the brain has remained enigmatic, with many steps in the process unexplained. A new study published last month in Proceedings of the National Academy of Sciences may fill in one piece of the puzzle, by showing that male sex hormones surge in the brain after exercise and could be helping to remodel the mind. The research was conducted on young, healthy and exclusively male rats – but scientists believe it applies to female rats, too, as well as other mammals, including humans. The decision to use only males was carefully considered. “We’ve known for a while that estrogen,” the female sex hormone, “is produced in the brain” not just of female animals but also, to some degree, in males, says Bruce S. McEwen, the director of the Laboratory of Neuroendocrinology at Rockefeller University in New York and an author of the study, which also involved scientists from the University of Tsukuba in Japan and other institutions. Estrogen has been well studied and has many effects, he said, including, scientists suspect, new brain cell growth. But far less has been known about the role of male sex hormones in mammalian brains, particularly after exercise. While both sexes produce male sex hormones, males produce far more of it – mostly in the gonads but, the researchers suspected, also in the brain. Copyright 2012 The New York Times Company

Keyword: Hormones & Behavior; Aggression
Link ID: 17250 - Posted: 09.13.2012

by Sari van Anders of the University of Michigan is an assistant professor of neurosciences; reproductive sciences; and science, technology and society. Her lecture is called “Beyond Sexual Orientation: Testosterone and Sexuality Diversity in Humans.” What do you mean by “beyond” sexual diversity? Sexual orientation is often assumed to refer to same-gender, other-gender, or mixed-gender sexual attractions. Despite this, we tend to lump sexual minority individuals and communities together whether they fit into this traditional sexual orientation model (lesbian, bisexual, gay) or not (kink, polyamory). With my talk, I plan to discuss how sexual orientation connects with other sexual minority categories and how testosterone research helps to reframe thinking about sexual diversity. What role does testosterone play in sexual orientation? I study adult circulating testosterone. I’ve found evidence that testosterone is related to something I call “relationship orientation” in men, and “relationship status” in women. In my talk I’ll be discussing how sexual diversity — including interest in multiple partners vs. one partner — might be more meaningfully studied in testosterone research. What’s the most interesting aspect of your research? My research moves across a lot of levels. I will be discussing really science-y stuff like hormones, really cultural stuff like identity and lots in between. © 2009 City Pulse

Keyword: Sexual Behavior
Link ID: 17249 - Posted: 09.13.2012

By Susan Milius Snakes in the wild sometimes forgo the mom-and-dad method of reproducing and have babies without having sex, researchers have confirmed with genetic testing. Occasional no-sex reproduction has been seen in captivity among snakes, Komodo dragons and sharks. But until now there has been no conclusive evidence for wild virgin birth among species that normally reproduce sexually, says Warren Booth of the University of Tulsa in Oklahoma. (In about 80 kinds of vertebrates, a single sex carries on the species quite well on its own.) Booth and his colleagues examined dozens of litters of wild-caught copperheads and cottonmouths. The team found one case in each species of a male baby born without littermates. Genetic testing showed that these babies’ maternal and apparently paternal DNA was identical at multiple locations, making the chances that a daddy snake actually was involved in the reproductive process vanishingly small. The researchers report their findings online September 12 in Biology Letters. © Society for Science & the Public 2000 - 2012

Keyword: Sexual Behavior
Link ID: 17248 - Posted: 09.13.2012

By Matthew Perrone, Associated Press "Do you have a decrease in libido?" "Have you noticed a recent deterioration in your ability to play sports?" "It could be Low-T." Welcome to the latest big marketing push by the nation's drug companies. In this case, it's a web page for Abbott Laboratories' Androgel, a billion-dollar selling testosterone gel used by millions of American men struggling with the symptoms of growing older that are associated with low testosterone, such as poor sex drive, weight gain and fatigue. Androgel is one of a growing number of prescription gels, patches and injections aimed at boosting the male hormone that begins to decline after about age 40. Drugmakers and some doctors claim testosterone therapy can reverse some of the signs of aging — even though the safety and effectiveness of such treatments is unclear. "The problem is that we don't have any evidence that prescribing testosterone to older men with relatively low testosterone levels does any good," says Dr. Sergei Romashkan, who oversees clinical trials for the National Institute on Aging, a part of the National Institutes of Health conglomerate of research centers. Low testosterone is the latest example of a once-natural part of getting old that has become a target for medical treatment. Bladder problems, brittle bones and hot flashes have followed a similar path: from inconvenient facts of life, to ailments that can be treated with drugs. The rise of such therapies is being fueled by both demographics and industry marketing. © 2012 NBCNews.com

Keyword: Hormones & Behavior; Aggression
Link ID: 17236 - Posted: 09.10.2012

By Susan Milius Caterpillars way too immature for actual sex turn out to detect and take an interest in adult sex pheromones. Caterpillars of the cotton leafworm moth (Spodoptera littoralis) don’t have working sex organs. They’re just long, black-green larvae eating as much as they can before transforming into the completely different body shape and lifestyle of an adult moth. Yet these caterpillars can sense, and appear to like, the adult sex pheromone of their species, an international team reports September 4 in Nature Communications. “This is a funny fact because sex pheromones are supposed to be for sex,” says coauthor Emmanuelle Jacquin-Joly of the French agricultural research agency INRA in Versailles. Adult female moths release puffs of these chemicals, and males catching a whiff — sometimes from considerable distances — sniff their way through the night to the female. Evolution may have repurposed some chemistry in this species, Jacquin-Joly and her colleagues propose. What means “come hither” to adult moths may indicate something quite different, perhaps “here’s food,” to a youngster, she says. She began looking for a cotton leafworm caterpillar pheromone response after another lab found that larval silkworm antennae make the adult-style proteins required to bind molecules of adult sex pheromones from the air and shuttle them to nerve cells. Young silkworms didn’t seem to use the information, but Jacquin-Joly wondered if young cotton leafworms, with a much broader diet, might respond differently. © Society for Science & the Public 2000 - 2012

Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 17227 - Posted: 09.07.2012

By Daisy Yuhas How do I love thee? When neuroscientist Young and journalist Alexander started counting, they found many molecular ways. In The Chemistry between Us, the writers highlight the complex chemical processes that create love in the brain and bolster the argument that love is an addiction. Young has devoted his career to studying the behaviors and neural circuitry of love in the prairie vole, a rodent whose monogamous tendencies resemble our own. Once a prairie vole has found “the one,” the pair will most likely remain companions for life. Young's research has implicated a range of chemical activities—mainly during sex—that build this lifelong bond. In particular, he uncovered how two hormones in the brain, vasopressin in male voles and oxytocin in female voles, regulate social behavior and memory—promoting the recognition of a loved one and the urge to cuddle or defend. In addition, the circulation of dopamine and opioids allows the vole to associate his or her partner with pleasure, thus strengthening their bond. Many of these molecules are identical to those activated in human bonding. That loving feeling comes at a price. A hormone called corticotropin-releasing factor, or CRF, builds up in the brains of paramours and parents alike. The CRF system activates a stress response, and this system elicits the painful sensations you feel when your baby cries or your boyfriend dumps you. The system may seem like a nasty trick, but it has its uses. Even when passion fades or a diaper needs changing, the sharp pangs of the CRF system keep families and loved ones together. The CRF system also contributes to the agony an addict feels after the elation wears off. Thus, the authors argue, the highs of intimacy and withdrawals of separation parallel the highs and lows that drug addicts experience. © 2012 Scientific American

Keyword: Sexual Behavior; Aggression
Link ID: 17199 - Posted: 08.25.2012

Steve Connor Babies of older fathers are more likely to carry genetic mutations than those of younger fathers. And the mutations could lead to illnesses such as autism and schizophrenia in later life, a landmark study has shown. Scientists have, for the first time, counted the number of new mutations linked with a father's age at the time of conception and have concluded that older men are significantly more likely to have children with potentially harmful genetic changes. The results could explain previous studies showing that certain mental and developmental illnesses with strong genetic components tend to be more common among people whose fathers were older at the time of conception. Although the age of a child's mother has been linked with problems associated with chromosomal defects, such as Down's syndrome, there has been scant information about the contribution made by older fathers to the future health of their offspring. "These observations shed light on the importance of the father's age on the risk of diseases such as schizophrenia and autism," the researchers say in their study published in the journal Nature. The scientists found that a new-born baby's genome contains around 60 new small-scale mutations compared with its parents and that the actual number of new mutations carried by each child was strongly dependent on the age of the father, rather than the mother, at the time of conception. The researchers, led by Augustine Kong and Kari Stefansson of deCode Genetics in Reykjavik, calculated that a 20-year-old father transmits about 25 new mutations to his child while a 40-year-old man will pass on 65. © independent.co.uk

Keyword: Autism; Aggression
Link ID: 17196 - Posted: 08.25.2012

Kathryn Lougheed A chemical in llama semen responsible for inducing ovulation in females has been identified and, surprisingly, it is a protein already known for its role in promoting the growth and survival of nerve cells in many species1. The protein — nerve growth factor (NGF) — is also found in human semen, suggesting that it may play a previously unsuspected role in human fertility. Whereas many animals, including humans, cattle and mice, produce eggs as part of a cycle of spontaneous ovulation, others — including llamas, camels, rabbits and koalas — are ‘induced ovulators’ that need a chemical stimulus. In 2005, Gregg Adams, a veterinary surgeon and reproductive scientist at the University of Saskatchewan in Saskatoon, Canada, and his colleagues showed that in llamas, the stimulus was in the seminal fluid2. In the latest study, published this week in the Proceedings of the National Academy of Sciences1, Adams led a team that identified the chemical as NGF. Although human women do not require NGF in semen to ovulate, Adams says that the protein could still have a direct effect on human fertility. Earlier this year, he published a paper3 showing that llama seminal fluid shortens the ovulation cycles of cows and seems to stimulate the development of the corpus luteum — a structure inside the ovaries that forms after an egg has been released and secretes hormones vital to pregnancy. In some cases, NGF could explain why some couples find it difficult to conceive, says Adams. A couple could have fertility problems if either the man failed to produce enough NGF in his semen or the woman lacked the receptors to detect and respond to it, he says. © 2012 Nature Publishing Group

Keyword: Sexual Behavior
Link ID: 17187 - Posted: 08.22.2012

By Brett Israel and Environmental Health News A widely used pesticide – banned in homes but still commonly used on farms – appears to harm boys’ developing brains more than girls’, according to a new study of children in New York City. In boys, exposure to chlorpyrifos in the womb was associated with lower scores on short-term memory tests compared with girls exposed to similar amounts. The study is the first to find gender differences in how the insecticide harms prenatal development. Scientists say the finding adds to evidence that boys’ brains may be more vulnerable to some chemical exposures. “This suggests that the harmful effects of chlorpyrifos are stronger among boys, which indicates that perhaps boys are more vulnerable to this type of exposure,” said Virginia Rauh, a perinatal epidemiologist at Columbia University and co-author of the study published in July. Chlorpyrifos is an organophosphate insecticide, a powerful class of pesticide that has toxic effects on nervous systems. It was widely used in homes and yards to kill cockroaches and other insects, but in 2001 the U.S. Environmental Protection Agency banned its residential use because of health risks to children. Since then, levels inside U.S. homes have dropped [PDF], but residue remains in many homes. In addition, many developing countries still use the pesticide indoors. Known by the Dow trade name Lorsban, chlorpyrifos is still sprayed on some crops, including fruit trees and vegetables, and also is used on golf courses and for mosquito control. About 10 million pounds of chlorpyrifos are applied to agricultural fields annually, according to the EPA. © 2012 Scientific American,

Keyword: Neurotoxins; Aggression
Link ID: 17186 - Posted: 08.22.2012

By Jonathan Ball BBC News Young male fruit flies learn the smell of a receptive female to avoid wasting their sexual efforts, research shows. Promiscuous male flies initially court all females, but are rejected by those who have already mated. It is clear that the flies eventually learn to spot mated females, but just how they do has remained a mystery. Research published in Nature suggests that they smell a chemical signal called a pheromone left by other males during mating. The studies were performed using the common fruit fly - Drosophila melanogaster. This insect is used widely in genetic studies because they are easy to grow and they reproduce quickly - but principally because it is possible to generate and study flies that possess changes - or mutations - in their genetic material. In the study, Prof Barry Dickson and colleagues from the Research Institute of Molecular Pathology in Vienna, Austria, performed a series of studies to identify the mechanism that led to this change in behaviour in older flies. Using complementary approaches, the team showed that a pheromone called cVA was responsible. Pheromones are substances produced by one individual which modify the behaviour of another. They are widely known to work in the animal kingdom to warn of danger, define territories or attract mates. Mosquito The finding could be used for the control of other insects such as mosquitoes, which spread malaria BBC © 2012

Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 17184 - Posted: 08.20.2012

Sleep apnea, a disorder characterized by snoring and daytime sleepiness that has been linked to cardiovascular disease, has primarily been viewed as a male problem, but a new Swedish study suggests the sleep disorder is also a common problem among women. Dr. Karl A Franklin of Umea University Hospital in Sweden and colleagues noted in the study released Wednesday that there have been only a few epidemiological studies conducted in women, and the frequency of the disorder in women "is still uncertain." Obstructive sleep apnea, in which a person has short pauses in breathing during sleep, may be caused by a temporary collapse of the airway. The gaps in breathing can last 10 to 30 seconds, and may occur dozens or hundreds of times each night. For their study, Franklin and the other Swedish researchers investigated 400 women from a population-based random sample of 10,000 women aged 20 to 70. The women answered a questionnaire and were monitored overnight. Obstructive sleep apnea was found in 50 per cent of the women subjects, with 14 per cent of them having a severe form of the disorder. Treatment for obstructive sleep apnea: For mild to moderate apnea, the best treatment is continuous positive airway pressure (CPAP). © CBC 2012

Keyword: Sleep
Link ID: 17170 - Posted: 08.16.2012

by Michael Slezak A lack of anti-Müllerian hormone in boys with autistic spectrum disorder (ASD) may lead to a greater number of symptoms. Michael Pankhurst and Ian McLennan from the University of Otago in New Zealand say hormones like anti-Müllerian hormone (AMH) that control the speed at which the body and brain develop might play a central role in the way that ASD progresses through childhood. The pair analysed the level of AMH in 82 boys with ASD. The lower the level of AMH in their blood, the greater the number of autistic traits they displayed. In an earlier study, McLennan and his colleagues found that an increased level of AMH was associated with slower overall growth and development in boys. Together, he thinks the two studies suggest that a lack of AMH could cause the brain to develop too quickly, leading to an increased number of symptoms in boys with ASD. "Rapid development is associated with a greater frequency of developmental disorders," says McLennan. A complex system that develops quickly is more likely to contain errors than one that develops more slowly, he explains. Surprisingly, there was no difference between the average level of anti-Müllerian hormone in the children with ASD and 16 boys without autism. McLennan says this shows that the hormone doesn't cause ASD, but may increase the number of symptoms in people who have the condition. © Copyright Reed Business Information Ltd.

Keyword: Autism; Aggression
Link ID: 17167 - Posted: 08.15.2012