Nature is fighting back in response to female promiscuity by producing a biological 'sperm' chastity belt, say US scientists. Semen becomes more sticky to act as a plug, thereby preventing sperm from competitors impregnating females who sleep around, they found. The Howard Hughes Medical Institute team, along with colleagues from Chicago and Kansas City, studied humans, monkeys and gorillas. The findings appear in Nature Genetics. The researchers examined the semen of 12 different species of primates. In species where the females were most promiscuous, the males had developed several strategies to ensure they would be the male most likely to father any offspring and pass on their genes. As well as having larger testicles and producing more sperm, the semen was more sticky. Chimpanzees, for example, which are a promiscuous species, had more advanced evolution of a gene controlling the stickiness of semen than gorillas, which tend to be monogamous and stay faithful to their partner for life. Humans were midway between, suggesting that while women are nothing like as promiscuous as chimps, neither are they as faithful as gorillas. (C)BBC

Keyword: Sexual Behavior; Evolution
Link ID: 6393 - Posted: 11.09.2004

By BENEDICT CAREY In a scene from the movie "Kinsey," opening in theaters on Friday, government agents seize a box of study materials being shipped by Dr. Alfred C. Kinsey, the pioneering sex researcher, and impound the contents as obscene. The scene portrays a time in American history, the 1940's and 1950's, when marital relations were rarely discussed and frank reporting about sex was greeted with a collective anxiety verging on horror. In 1948, when Dr. Kinsey published "Sexual Behavior in the Human Male," he was called a pervert, a menace and even a Communist. Much has changed in the years since then. But scientists say one thing has remained constant: Americans' ambivalence about the scientific study of sexuality. Decades after the sexual revolution, sex researchers in the United States still operate in a kind of scientific underground, fearing suppression or public censure. In a culture awash in sex talk and advice in magazines and movies and on daytime TV, the researchers present their findings in coded language, knowing that at any time they, like Dr. Kinsey, could be held up as a public threat. Copyright 2004 The New York Times Company

Keyword: Sexual Behavior
Link ID: 6392 - Posted: 11.09.2004

SALT LAKE CITY - NASA (news - web sites) scientists are studying autistic savant Kim Peek, hoping that technology used to study the effects of space travel on the brain will help explain his mental capabilities. Last week, researchers had Peek — who was the basis for Dustin Hoffman's character in the 1988 film "Rain Man" — undergo a series of tests including computerized tomography and magnetic resonance imaging, the results of which will be melded to create a three-dimensional look at his brain structure. The researchers want to compare a series of MRI images taken in 1988 by Dr. Dan Christensen, Peek's neuropsychiatrist at the University of Utah, to see what has since changed within his brain. Not only are Peek's brain and his abilities unique, noted Richard D. Boyle, director of the California center performing the scans, but that he seems to be getting smarter in his specialty areas as he ages is unexpected. The 53-year-old Peek is called a "mega-savant" because he is a genius in about 15 different subjects, from history and literature and geography to numbers, sports, music and dates. But he also is severely limited in other ways, like not being able to find the silverware drawer at home or dressing himself. Copyright © 2004 Yahoo! Inc

Keyword: Autism
Link ID: 6391 - Posted: 06.24.2010

BOSTON - Scientists for the first time have identified a fault in the brain waves of schizophrenics that may explain their hallucinations and disturbed thinking. The study, by a team at the Veterans Affairs (VA) Boston Healthcare System and Harvard Medical School, appears in the Nov. 8 Proceedings of the National Academy of Sciences. The researchers studied the brain waves of normal and schizophrenic patients as they responded to images. Those with the disorder showed no electrical activity in a certain frequency-the "gamma" range, from 30 to 100 brain waves per second-that healthy brain cells use to exchange information about the environment and form mental impressions. "The schizophrenics did not show this gamma-band response at all. There was a pretty dramatic difference," said senior author Robert W. McCarley, MD, deputy chief of staff for mental health services at the VA Boston Healthcare System and chair of the Harvard psychiatry department. The brain contains hundreds of billions of neurons, or nerve cells. Researchers believe our thoughts are created when large groupings of these neurons "fire"-send messages to each other, through bursts of electrical activity-at the same frequency. Different frequencies, measured in hertz, or cycles per second, indicate different levels and types of activities. Delta waves, below 4 hertz, occur during sleep. Alpha waves, 8 to 13 hertz, occur at relaxed, quiet times. Beta waves are the next fastest, occurring when we are actively thinking.

Keyword: Schizophrenia
Link ID: 6390 - Posted: 11.09.2004

By analyzing the effects of altered neuronal function in mice, researchers have gained new understanding of how changes in a particular neuronal characteristic, neuronal excitability, may negatively impact learning and memory as we age. The work is reported by Geoffrey Murphy and Alcino Silva and their colleagues at the University of California, Los Angeles. Learning and memory impairments that arise independent of overt pathology are considered to be a normal component of aging. It is estimated that about 40% of people over the age of 65 years suffer from some sort of age-related cognitive decline. The exact cause of these age-related deficits in learning and memory is not currently known, but there have been numerous studies in the past that have implicated age-related changes in two neuronal attributes: a decrease in neuronal excitability, or the ability of neurons to be stimulated to fire, and age-related deficits in synaptic plasticity, or the ability of neurons to change some types of connections to other neurons. In the new study, funded by the National Institutes of Aging, researchers have established the link among neuronal excitability, synaptic plasticity, and aging. Studying mice that had been genetically engineered to lack a particular ion channel auxiliary subunit, the researchers showed that the mice maintained enhanced neuronal excitability into old age, and, most importantly, that these mice exhibit a reduction in the threshold for the induction of specific forms of synaptic plasticity – in other words, these mice appear to change some kinds of inter-neuronal connections more readily than do normal mice of the same age.

Keyword: Learning & Memory; Alzheimers
Link ID: 6389 - Posted: 06.24.2010

The world's most popular drug is something you could very well have in a cup in front of you next to your computer right now—caffeine. "Caffeine is the world's most widely used mood-altering drug," says Roland Griffiths, professor of behavioral biology at the Johns Hopkins University School of Medicine. "Some 80 percent of the population use caffeine on a daily basis. Caffeine is so available in our culture and society that many people consume coffee and soft drinks without the realization that they're actually involved in a drug self-administration behavior." According to Griffiths, physicians haven't recognized withdrawal from caffeine as a disorder that can affect our performance—or even make us sick. "Most people are aware that caffeine is a mild stimulant drug and they're aware of those stimulant effects when they take caffeine," he says. "Fewer people really appreciate the extent to which caffeine produces withdrawal when they try and stop their caffeine use." He points out that the symptoms of caffeine withdrawal haven't been systematized as a disorder in the DSM-IV, or Diagnostic and Statistical Manual of Mental Disorders, considered the bible of mental disorders. So Griffiths analyzed medical studies of caffeine withdrawal dating back 170 years. "Sixty-six different studies had been done over time, most of which actually had been done in the last 10 years," he says. © ScienCentral, 2000- 2004.

Keyword: Drug Abuse
Link ID: 6388 - Posted: 06.24.2010

Birds are pretty far away from humans on the evolutionary ladder. But scientists have found that songbirds have a gene that is important in human language learning. "There is a connection between human language and bird vocal imitation at the genetic level," says Erich Jarvis, a neurobiologist at Duke University. "What we discovered is that songbirds and other birds that have the ability to imitate sounds contain a gene called FoxP2 that is known to be involved in human language. It's the first time we have a gene that we can study now in songbirds that we know is linked to language in humans." The FoxP2 gene was found to be involved in human language several years ago. Its mutation produces an inherited language deficit called an oral apraxia. People with this deficit have an inability to pronounce words correctly, form them into sentences that are grammatically correct, and understand complex language. "We decided to look for this gene in other species of animals who can actually imitate sounds like humans can do," explains Jarvis. "And this is a very rare trait. Only hummingbirds, parrots, and songbirds, as well as bats and dolphins, have this ability. So we studied birds, and what we found is that birds also have this same gene." © ScienCentral, 2000- 2004.

Keyword: Language; Genes & Behavior
Link ID: 6387 - Posted: 06.24.2010

New Research Shows Mandarin Speakers More Likely to Acquire Rare Musical Ability By Inga Kiderra Could it be that cellist Yo-Yo Ma owes his perfect musical pitch to his Chinese parents? While we may never know the definitive answer, new research from the University of California, San Diego has found a strong link between speaking a tone language – such as Mandarin – and having perfect pitch, the ability once thought to be the rare province of super-talented musicians. The first large-scale, direct-test study to be conducted on perfect pitch, led by psychology professor Diana Deutsch of UC San Diego, has found that native tone language speakers are almost nine times more likely to have the ability. Results will be presented Nov. 17 at the meeting of the Acoustical Society of America in San Diego. Perfect, or absolute, pitch is the ability to name or produce a musical note of particular pitch without the benefit of a reference note. The visual equivalent is calling a red apple “red.” While most people do this effortlessly, without, for example, having to compare a red to a green apple, perfect pitch is extremely rare in the U.S. and Europe, with an estimated prevalence in the general population of less than one in 10,000. Copyright ©2001 Regents of the University of California.

Keyword: Hearing; Language
Link ID: 6386 - Posted: 06.24.2010

The identity of the protein which is key to developing long-term memory has been confirmed. say US scientists. The discovery may lead to advancements in treatment for Alzheimer's disease and other people with memory loss. Scientists have suspected for a long time that the mBDNF protein plays a role in memory development. But the Institutes of Health team claims in the journal Science to have proved the protein is the key, using experiments on mouse brains. Protein mBDNF, which stands for mature brain-derived neurotrophic factor, is produced by a chemical reaction involving the enzyme plasmin and proBDNF. The team carried out a series of experiments on mice brains, which are easy to mutate, to see how the protein affected long-term memory and what was needed to create the protein. In tests where the mouse brain was incapable of producing mBDNF, long-term memory formation was not possible. But when the conditions were right to produce mBDNF, the researchers, including teams from Cornell University in New York and the Chinese University of Hong Kong, found long-term memory development was possible. Dr Bai Lu, of the National Institute of Child Health and Human Development, part of the National Institutes of Health, said the findings had the potential to treat people with Alzheimer's disease. "The fundamental problem is the part of the brain associated with memory is dying. If you can stop it from dying or improve the functions of memory you can help patients with Alzheimer's disease." But he admitted doctors were not yet at the stage where they could alleviate memory deficits - as the substance which creates plasmin, which it is thought people with Alzheimer's disease lack, can affect the blood. The possibility that mBDNF could play a key role in long-term memory was first raised in 1996 and since then doctors have established how the protein is formed during chemical reactions involving plasmin and other proteins (C)BBC

Keyword: Learning & Memory; Trophic Factors
Link ID: 6385 - Posted: 11.08.2004

By CLIFFORD KRAUSS VANCOUVER, British Columbia - Beverley Sharpe wondered what was wrong when her 2-year-old daughter, Allison, did not talk. Something seemed askew when her child would not respond to a rolling ball but would find great pleasure from running her hands repetitively through a bowl of soaking beans. A diagnosis of autism resolved the mystery. But the Sharpes' marriage broke up and Ms. Sharpe was left to pay for Allison's intensive therapy on her own. Ms. Sharpe dug in her heels. She refurbished and rented out her garage and rented out several more rooms of her West Vancouver house to pay for the 36 hours of therapy Allison needed every week from four therapists, costing more than $1,400 a month. She also joined a group of parents with autistic children in filing a suit in 1998 seeking public financial aid to meet the children's needs. The case has since wound its way through the British Columbia provincial courts and has reached the Supreme Court of Canada to become one of the most important cases touching social policy to come before the high court in years. Provincial governments are now paying for some services for autistic children, but overall Canadian autistic children currently have fewer legal rights than American children with the same neurological disorder. The American children are entitled by federal legislation to receive educational therapy in their public schools, although services are spotty, depending on how well the local district complies. Copyright 2004 The New York Times Company

Keyword: Autism
Link ID: 6384 - Posted: 11.08.2004

By JOHN SCHWARTZ and JAMES ESTRIN Dr. Jules Lodish welcomes visitors to the downstairs bedroom of his Bethesda, Md., home with a robotic greeting that bursts from his computer's speaker. Ten years of living with amyotrophic lateral sclerosis, or A.L.S., a progressive, paralyzing disease, have stilled nearly every muscle; he types with twitches of his cheek, detected by a sensor clipped to his glasses. But ask him how he feels about his life, and Dr. Lodish, his eyes expressing the intensity denied to his body, responds: "I still look forward to every day." A.L.S., or Lou Gehrig's disease, is often described as a kind of living death in which the body goes flaccid while the mind remains intact and acutely aware. The prospect of being trapped in an inert body and being totally dependent on others drives many sufferers to suicide. When Attorney General John Ashcroft attacked an Oregon law allowing doctor-assisted suicide in 2001 - a case that is still working its ways through the legal system - patients with the disease were among those who supported the law in court. But while the legal case and much of the national attention has focused on the issue of the right to die, less is known about those patients who want to live, and, like Dr. Lodish, will go to extraordinary lengths to do so. Copyright 2004 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 6383 - Posted: 11.08.2004

Ron G. Weisman, Laurene Ratcliffe More than 2,000 years ago, the acerbic philosopher Marcus Tullius Cicero observed that Roman songbirds compose more excellent melodies than any musician. He certainly doesn't stand alone in history on that count; it is a nearly universal human experience to find joy and wonder in birdsong—and to compare the songs to human music. People have been transcribing melodies of birds into the notation of music since at least the 18th century; Vivaldi's Goldfinch concerto and Handel's Cuckoo and the Nightingale organ concerto include musical notation for birdsongs. In the early 1900s, the New England naturalist and composer F. Schuyler Mathews presented the songs of many North American birds in musical notation in his Field Book of Wild Birds and Their Music in order to help readers identify species common in the eastern United States. Later biologists did not share Mathews's enthusiasm for musical descriptions of birdsongs. Donald Borror, a master bioacoustician and field biologist, found many of the song descriptions inadequate by modern standards, as he wrote in his foreword to the 1967 reprinting of Mathews's book. Borror acknowledged that Mathews lacked modern electronic equipment and that his primary interest was in the musical content of birdsongs. Today, however, Mathews's approach seems dated and quaint. Musical notation is simply unable to provide the detailed, accurate and reproducible descriptions required in modern bioacoustical analyses of vocal communication among songbirds. Mathews's approach helps musically trained people recognize birdsongs, but it fails to objectively describe birdsongs and calls. For bioacousticians, accurate observations are a crucial first step in analyzing the role of songs in the life of a species. © Sigma Xi, The Scientific Research Society

Keyword: Hearing; Evolution
Link ID: 6382 - Posted: 06.24.2010

The identification of brain receptors in mice that seem to control nicotine addiction may lead to new drugs to help smokers quit, researchers hope. It is thought nicotinic acetylcholine receptors found on the surface of brain cells are key. The team from the California Institute of Technology found that carrying a particular variant of the receptor increases vulnerability to nicotine. The findings are published in the journal Science. The receptors can be composed of different combinations of subunits. The California team discovered that mice with a mutation in the "alpha4" subunit were unusually sensitive to the effects of nicotine. Compared to normal neurons, the mutant neurons responded to lower concentrations of nicotine and, after this exposure, they also responded more robustly to larger doses. Behavioral tests showed that mutant mice exhibited signs of addiction at lower doses than normal mice. Professor Robert West, of the Cancer Research UK Health Behaviour Unit at University College London, said: "This study is useful in helping with development of medications that target the receptors involved in nicotine dependence but not others and so minimising unwanted side effects." (C)BBC

Keyword: Drug Abuse
Link ID: 6381 - Posted: 11.06.2004

Research on nicotine's molecular targets in the brain has provided new insight into the mechanism of nicotine addiction. The researchers hope that their work, published in the 5 November issue of Science, may one day lead to more effective ways to wean people off tobacco. Nicotine's addictive power comes from its ability to elicit pleasure by mimicking chemicals that stimulate the brain's "reward" circuits. One of these chemicals is acetylcholine. Once in the brain, nicotine hijacks neurons' receptors for acetylcholine, causing them to fire even in the absence of the real thing. Acetylcholine receptors are made up of several subunits. Scientists have identified 12 such subunits that can be mixed and matched to form receptors with different physiological properties. But they haven't been able to nail down which subunits are the most important for addiction. To narrow down the list, a team of researchers led by Henry Lester, a neuroscientist at the California Institute of Technology in Pasadena, designed a mouse with a mutant version of the a4* acetylcholine receptor subunit. Acetylcholine receptors containing the mutant subunit were about 50 times more sensitive than usual. That meant that the scientists could activate the a4*-containing receptors with doses of nicotine too small to affect other types of acetylcholine receptors. Even on these low doses of nicotine, the genetically engineered mice still exhibited the classic symptoms of addiction. The results provide strong evidence that the a4* receptors are sufficient to create nicotine addiction. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Drug Abuse
Link ID: 6380 - Posted: 06.24.2010

Diana Parsell Small doses of nicotine can halt the progression of the often-fatal condition called sepsis, according to experiments in mice. The finding, coupled with tests of nicotine on cultured human cells, suggests a pathway to more-effective therapies for the infection-triggered problem. Twice as many mice injected with nicotine survived at least 3 weeks after sepsis set in than did mice receiving inert injections. Luis Ulloa of the Institute for Medical Research at North Shore-Long Island Jewish Health System in Manhasset, N.Y., and his coinvestigators conclude that the treatment works by inhibiting overproduction of an immune system molecule that promotes inflammation. Other studies have suggested that nicotine may be effective against inflammatory diseases such as ulcerative colitis, which is chronic inflammation of the large intestine. When Ulloa and his colleagues began experimenting in lab dishes with human macrophages, a type of immune system cell, they discovered that the biochemical acetylcholine put the brakes on the cells' production of the protein called high mobility group box 1 (HMBG1). This protein is one of the family of immune chemicals called cytokines, which play a role in infection-fighting inflammation. In sepsis, however, HMBG1 overstimulates inflammation. Copyright ©2004 Science Service

Keyword: Drug Abuse
Link ID: 6379 - Posted: 06.24.2010

New York, NY, - Researchers at Columbia University Medical Center have found two locations in the human genome that may harbor genes that increase the risk of Alzheimer’s disease. If confirmed, they will be the first genes linked to Alzheimer’s disease since ApoE4 was discovered in 1993. The findings are published in the November issue of Molecular Psychiatry, a journal of the Nature Publishing Group. “We feel confident that we may be closing in on new Alzheimer’s genes,” says the study’s senior author, Richard Mayeux, M.D., co-director of the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain at Columbia University Medical Center. “This is a major collection of families, and family studies really give you more confidence that the region you’re looking at is significant.” Researchers think that Alzheimer’s is caused by the interaction of several different genes, but so far only one gene, ApoE4, has been linked conclusively to the disease. Finding the other genes will be a huge step toward understanding how Alzheimer’s begins and how it can be treated. It will also allow clinicians to predict who will develop Alzheimer’s later in life and who will benefit from drugs that prevent the disease. The new study found strong evidence for new Alzheimer’s genes on chromosomes 18 and 10. The region on 18 had never been strongly linked to the disease before, while the link to chromosome 10 confirms previous findings by other Alzheimer’s researchers.

Keyword: Alzheimers
Link ID: 6378 - Posted: 06.24.2010

Helen Pearson An immense database of Parkinson's disease patients is being launched in California. Medical researchers say the database will be essential for tracking down the causes of the disease. Once established, the state-wide registry will be the biggest for the disease in the world. It gained formal approval in late September when Governor Arnold Schwarzenegger signed a bill requiring doctors to register every new patient diagnosed with the movement disorder in a central database. Researchers say the new registry will be crucial for pinning down which environmental factors, such as pesticides or diet, are important in triggering the disease. This has become a priority with the growing realisation that genes alone cannot explain people's risk. Parkinson's is caused when dopamine-producing cells in the brain die or are damaged, causing symptoms such as tremors, stiff or slow movement and problems with balance. Although the disease is thought to affect as many as 2% of people, researchers have struggled to build up an accurate picture of the types of people it strikes. Unlike cancer, for example, the disease is rarely recorded as a cause of death because patients succumb to other conditions. ©2004 Nature Publishing Group

Keyword: Parkinsons
Link ID: 6377 - Posted: 06.24.2010

CHAPEL HILL -- University of North Carolina at Chapel Hill scientists have reported - for the first time - a burst in new brain cell development during abstinence from chronic alcohol consumption. The UNC findings, from research at UNC's Bowles Center for Alcohol Studies, were based on an animal model of chronic alcohol dependence, in which adult rats were given alcohol over four days in amounts that produced alcohol dependency. The study is in the Nov. 3 issue of the Journal of Neuroscience. In 2002, Dr. Fulton T. Crews, Bowles Center director, and Bowles Center research associate Dr. Kim Nixon were the first to report that alcohol, during intoxication, has a detrimental effect on the formation of new neurons in the adult rat hippocampus. This brain region is important for learning and memory - in animals and humans - and is linked to psychiatric disorders, particularly depression. "When used in excess, alcohol damages brain structure and function. Alcoholics have impairments in the ability to reason, plan or remember," said Crews, also professor of pharmacology and psychiatry in UNC's School of Medicine. "A variety of psychological tests show alcoholics have a difficulty in ability to understand negative consequences."

Keyword: Drug Abuse; Neurogenesis
Link ID: 6376 - Posted: 11.06.2004

William Cocke Something fishy is happening in the headwaters of the Potomac River. Scientists have discovered that some male bass are producing eggs—a decidedly female reproductive function. In June 2002 reports appeared of fish die-offs in the South Branch of the Potomac River. The West Virginia Division of Natural Resources asked U.S. Geological Survey (USGS) scientists to examine fish health in the watershed near the town of Moorefield, about three hours' drive from Washington, D.C. Anglers were also reporting fish with lesions. USGS scientists determined that some of the lesions indicated exposure to bacteria and other contaminants. The following year, the USGS conducted a more intensive assessment with a statistically significant number of fish, this time looking for internal damage. That's when they discovered a so-called intersex condition—where one sex exhibits both testicular and ovarian tissue. "It was not something we were really looking for," said Vicki Blazer, a fish pathologist with the USGS's Leetown Science Center in Kearneysville, West Virginia. Some 42 percent of male smallmouth bass surveyed showed signs of intersex development. A second sampling this spring produced an even higher rate—79 percent showed sexual abnormalities. © 2004 National Geographic Society.

Keyword: Sexual Behavior
Link ID: 6375 - Posted: 06.24.2010

LOCAL hospitals are not allowed to do brain surgery on drug addicts as a means of curing them of their bad habit, according to sources in the Ministry of Health, the Shanghai Morning Post reported. Previously some Chinese clinics had launched experimental projects using such methods. The paper released by the health ministry said such brain surgery is still in the experimental stage, and clinical research on its safety and effectiveness has not been concluded. So far no conclusions can be made about the exact point in the brain the surgery should target, nor the most successful techniques to use. Until now this surgery has not been widely popularized by clinics as a means of curing drug addicts. Prior to the new policy, two Shanghai hospitals, Renji and Huashan, had begun to offer such services, and a total of 29 patients had undergone the operation. Sources with the two hospitals said they had not received any such paper from the health ministry. However, they insisted that if they did receive such instructions they would of course stop providing the operations as soon as possible. Copyright by Shanghai Star.

Keyword: Drug Abuse
Link ID: 6374 - Posted: 11.06.2004