By JANE E. BRODY There's no question that the amount of lead in children's blood has dropped significantly in recent decades, much to the benefit of their brains and bodies. There's also no question that children who are still being permanently damaged by excessive lead levels live mainly at the poverty level or near it, in neighborhoods where they can be poisoned by lead from contaminated paint, water, soil and dust. More Personal Health Columns However, no one at any level of society, not even those with seven-figure incomes, can afford to be complacent about the exposure of children to lead in home and play environments. Here are some disturbing facts important to everyone concerned about the damage lead can cause and its individual and societal costs. About a quarter of the nation's children are exposed to lead at home, and more than 400,000 children are found each year to harbor amounts of lead deemed hazardous to normal mental and physical development. Environmental exposure to lead in early childhood is a prelude to a host of societal ills. It is associated with an increased risk of reading problems, school failure, delinquency and criminal behavior. Copyright 2006 The New York Times Company

Keyword: Neurotoxins; Development of the Brain
Link ID: 8416 - Posted: 01.19.2006

By IAN FISHER and CORNELIA DEAN ROME, - The official Vatican newspaper published an article this week labeling as "correct" the recent decision by a judge in Pennsylvania that intelligent design should not be taught as a scientific alternative to evolution. "If the model proposed by Darwin is not considered sufficient, one should search for another," Fiorenzo Facchini, a professor of evolutionary biology at the University of Bologna, wrote in the Jan. 16-17 edition of the paper, L'Osservatore Romano. "But it is not correct from a methodological point of view to stray from the field of science while pretending to do science," he wrote, calling intelligent design unscientific. "It only creates confusion between the scientific plane and those that are philosophical or religious." The article was not presented as an official church position. But in the subtle and purposely ambiguous world of the Vatican, the comments seemed notable, given their strength on a delicate question much debated under the new pope, Benedict XVI. Advocates for teaching evolution hailed the article. "He is emphasizing that there is no need to see a contradiction between Catholic teachings and evolution," said Dr. Francisco J. Ayala, professor of biology at the University of California, Irvine, and a former Dominican priest. "Good for him." Copyright 2006 The New York Times Company

Keyword: Evolution
Link ID: 8415 - Posted: 01.19.2006

By ELISABETH ROSENTHAL ROME, - In "Don Juan" Lord Byron wrote, "Sweet is revenge - especially to women." But a study released Wednesday, bolstered by magnetic resonance imaging, suggests that men may be the more natural avengers. In the study, when male subjects witnessed people they perceived as bad guys being zapped by a mild electrical shock, their M.R.I. scans lit up in primitive brain areas associated with reward. Their brains' empathy centers remained dull. Women watching the punishment, in contrast, showed no response in centers associated with pleasure. Even though they also said they did not like the bad guys, their empathy centers still quietly glowed. The study seems to show for the first time in physical terms what many people probably assume they already know: that women are generally more empathetic than men, and that men take great pleasure in seeing revenge exacted. Men "expressed more desire for revenge and seemed to feel satisfaction when unfair people were given what they perceived as deserved physical punishment," said Dr. Tania Singer, the lead researcher, of the Wellcome Department of Imaging Neuroscience at University College London. Copyright 2006 The New York Times Company

Keyword: Sexual Behavior; Emotions
Link ID: 8414 - Posted: 01.19.2006

Antipsychotic drugs can limit the behavioural abnormalities associated with a parasitic infection called toxoplasmosis in some rats – the condition causes them to become “suicidally” attracted to cats. The findings provide insight into a possible cause of schizophrenia, say the researchers behind the new study. The results also hint that anti-psychotic medications such as haloperidol – used to control the symptoms of schizophrenia – could serve as much-needed treatments against the dormant stage of toxoplasmosis in humans, says Joanne Webster of Imperial College London, UK, and one of the study team. She adds, however, that “it’s still very much a black box as to how these drugs work” to fight the parasitic infection. A latent toxoplasmosis infection might produce schizophrenia in humans, according to a theory by Fuller Torrey of the Stanley Medical Research Institute in Maryland, US, and a co-author on the study. But other experts stress the possibility that genes or even marijuana abuse may predispose a person to this type of disorder. The idea that toxoplasmosis triggers schizophrenia remains “on the fringes”, according to Paul Corry, a spokesperson for the mental illness charity Rethink in London, UK. © Copyright Reed Business Information Ltd

Keyword: Schizophrenia
Link ID: 8413 - Posted: 06.24.2010

By KATE ZERNIKE A sharp increase in the number of people arriving in emergency rooms with methamphetamine-related problems is straining local hospital budgets and treatment facilities across the country, particularly in the Midwest, according to two surveys to be released in Washington today. The studies, conducted late last year by the National Association of Counties, are another indicator of the toll the drug has taken on local communities, particularly in rural areas where social service networks are ill-equipped to deal with the consequences. In July, the association reported that an overwhelming number of sheriffs polled nationwide declared methamphetamine their No. 1 law enforcement problem. In the most recent survey, conducted late last year, 73 percent of the 200 county and regional hospitals polled said they had seen an increase in the number of people visiting emergency rooms for methamphetamine-related problems over the last five years; 68 percent reported a continued increase in the last three years, and 45 percent in the last year. The problem was particularly intense in the middle of the country: 70 percent of hospitals in the Midwest and 80 percent in the Upper Midwest said methamphetamine accounted for 10 percent of their patients. Nationwide, 14 percent of the hospitals said such cases made up 20 percent of their emergency room visits. Copyright 2006 The New York Times Company

Keyword: Drug Abuse
Link ID: 8412 - Posted: 01.18.2006

Female rats appear to be affected more than males by stress early in life, leading to a higher likelihood of cocaine addiction and eating disorders as adults, according to a study by Yale School of Medicine researchers in Neuropsychopharmacology. "These results differ somewhat from our previous study conducted with male rats," said Therese Kosten, research scientist, Department of Psychiatry, and lead author of the study. "Early life stress produces a greater increase in cocaine self-administration in female versus male rats." In addition, the neonatal stress enhances responding for food treats in female, but not male, rats, she said. "We believe this may suggest that women with early life stress have an enhanced risk of developing drug addiction, as well as eating disorders," Kosten said. Of the rats in the research, some were isolated from their mothers as "infants." The rats were studied as adults who had learned to self-administer cocaine and food treats. The researchers found the rats that had been kept in isolation worked harder to obtain food and drug rewards. © 2003-2006 Medical News Today

Keyword: Drug Abuse; Stress
Link ID: 8411 - Posted: 06.24.2010

Lacking a sense of humor might not just be bad for your social life, it might also be harming your cardiovascular health. A new study shows that laughter actually increases blood flow in the body, proving the old adage laughter is the best medicine right, at least when it comes to the heart. Cardiologist Michael Miller and colleagues at the University of Maryland tested blood flow in 20 healthy men and women after they watched 15 to 30 minute clips of funny movies--Kingpin and There's Something About Mary--and a stressful film--the opening sequence of Saving Private Ryan. The researchers measured blood flow both before each viewing began and one minute after it ended. "We wanted to see whether laughter induced a vascular response," Miller explains. Prior research inspired the team to conduct the experiment. A series of questionnaires administered to sufferers of coronary heart disease by the cardiologists revealed that patients who suffered a heart attack failed to find the humor in a situation like wearing the same outfit to a party 40 percent more often than their healthy counterparts. "We didn't know whether that was cause and effect or just part and parcel of having the disease," Miller says. © 1996-2006 Scientific American, Inc.

Keyword: Emotions
Link ID: 8410 - Posted: 06.24.2010

DALLAS - - By deleting a single gene in a small portion of the brains of mice, researchers at UT Southwestern Medical Center found that the animals were affected in a way resembling schizophrenia in humans. After the gene was removed, the animals, which had been trained to use external cues to look for chocolate treats buried in sand, couldn't learn a similar task, the researchers report in a paper appearing in today's issue of The Journal of Neuroscience. The researchers deleted the gene, which codes for a part of a protein involved in passing signals between nerve cells needed for learning and memory. When a similar protein is blocked by drugs in humans, it leads to a psychotic state similar to schizophrenia. "We think that both our genetic rodent model as well as a new learning and memory test we developed may provide valuable tools in the investigation of schizophrenia," said Dr. Robert Greene, professor of psychiatry and senior author of the study. Copyright 2006. The University of Texas Southwestern Medical Center at Dallas

Keyword: Schizophrenia; Learning & Memory
Link ID: 8409 - Posted: 01.18.2006

Nerve cells store and transmit information via special contact sites called synapses. Synapses also play a role in determining what we remember and what we forget. When we learn, both the structure and the functional characteristics of these contact sites change. Scientists are only now beginning to understand the molecular processes which cause that change. Researchers led by Michael Kiebler at the Max Planck Institute for Developmental Biology in Tübingen (now at the Center for Brain Research, University of Vienna) have identified a protein that is essential for the maintenance of synapses: if the protein Staufen2 is removed in a nerve cell, the cell loses a large portion of its synapses. Moreover, signalling at the remaining contact sites is significantly impaired. Staufen proteins are involved in the transport of molecular blueprints (mRNAs) to specific locations in a cell. The disturbance in the structure and function of synapses without Staufen2 protein suggests that mRNA transport to synapses is crucial to their maintenance and the storage of memory (Journal of Cell Biology, January 17, 2006). Nerve cells receive signals from other nerve cells via dendrites, which branch out like the branches of a tree. The cell-body receives incoming information, and transmits it further through the axon, a long projection from the cell. Nerve cells make contact with each other at highly-specialised locations known as synapses. There, information is not only passively transmitted. Synapses can, depending on input, change and in this way store new memory.

Keyword: Development of the Brain; Learning & Memory
Link ID: 8408 - Posted: 01.18.2006

KINGSTON, Ont. - Anticipating our own touch - for example in tickling oneself - reduces its impact, says Queen's psychologist Dr. Randy Flanagan, a member of the university's Centre for Neuroscience Studies. This is evidence of an important human adaptation that helps us interact with objects in our environment. An expert in eye/hand movement, Dr. Flanagan is part of an international team exploring sensory attenuation - the way that we filter out or "cancel" unnecessary information from the world around us. Their study appears on-line today in the international journal Public Library of Science (PloS) - Biology. Led by Paul Bays of University College London, the team also includes Daniel Wolpert of Cambridge University. "It's well-known that you can't tickle yourself," says Dr. Flanagan. "One explanation is that since all the sensations are completely predictable, we do 'sensory attenuation' which reduces our touch perception." Because people continually receive a barrage of sensory information, it's necessary to distinguish between what is caused by our own movements and what is due to changes in the outside world. ©Queen's University, 2005

Keyword: Pain & Touch
Link ID: 8407 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Swordtails, colorful, common aquarium fish, size up their swords before fighting, and often a male just has to show his big sword to scare off challengers, according to a new study in the latest Animal Behavior journal. Yet another study in the same publication concluded that female swordtails prefer male swordtails with big, striped swords. Researchers even think the female fixation on these bright appendages led to their emergence in the first place, since female fondness for novel traits and bright colors appears to have preceded the appearance of swords on males. The finding suggests the creation of some secondary sexual characteristics may be influenced, and even controlled, by the opposite sex. For male swordtails, this characteristic is an extension of the caudal fin, or tail, that looks like a pointy sword. "It is not terribly rigid and cannot be manipulated very efficiently," said Kari Benson, who co-authored the first paper with Alexandra Basolo. "It is not useful as a weapon. It is only used as a visual signal in a fight." © 2006 Discovery Communications Inc.

Keyword: Sexual Behavior
Link ID: 8406 - Posted: 06.24.2010

Alison Motluk Aspirin prevents cardiovascular events in both women and men – but in different ways, a new meta-study suggests. In women, aspirin reduces strokes, and in men it cuts down on heart attacks. But there are no statistically significant benefits the other way round, according to the analysis. “It appears that women respond differently to a given dose of aspirin than men,” says David Brown, a cardiologist at the Stony Brook School of Medicine in New York, US, and one of the authors. “Everything about the study is telling us that there’s a gender difference and we don’t understand it.” In people who already have cardiovascular disease, the benefits of low-dose aspirin are well-established – in both sexes. Aspirin’s cardiovascular effects are exerted by blocking the synthesis of thromboxane A2, a substance that causes the blood to clot. Even a single 100 milligram dose can be effective. But in people with moderate risk, the picture is less clear. Studies seem to indicate a reduction in coronary events, but most studies included few, if any, women. Brown and colleagues were interested in knowing if moderate-risk women would benefit to the same degree as men. © Copyright Reed Business Information Ltd

Keyword: Stroke; Sexual Behavior
Link ID: 8405 - Posted: 06.24.2010

By ERIC NAGOURNEY Millions of Americans have drunk alcohol on the job or before going to work, a new study suggests. Much has been written about how alcohol use and abuse affect work performance through absenteeism and other problems. This study, in the current Journal of Studies on Alcohol, set out instead to look at the extent of alcohol use and impairment. The researchers, led by Michael R. Frone of the Research Institute on Addictions at the State University of New York at Buffalo, surveyed 2,800 adults in 48 states, asking how often they drank alcohol within two hours of reporting to work, how often they drank it on the job and how often they worked feeling the effects of alcohol or having a hangover. In all, 15 percent of the people surveyed said that over the previous year, they had fallen into one of those categories at least once, with young people and those working nontraditional shifts most likely to do so. Among the jobs most affected by alcohol use are those in sales, entertainment, sports, media and maintenance. While the findings suggest that alcohol use or impairment at work is not commonplace, the incidence is still great enough to warrant closer attention from employers, Dr. Frone said. Copyright 2006 The New York Times Company

Keyword: Drug Abuse
Link ID: 8404 - Posted: 01.17.2006

By DONALD G. McNEIL Jr. In the small world of people who train dogs to sniff cancer, a little-known Northern California clinic has made a big claim: that it has trained five dogs - three Labradors and two Portuguese water dogs - to detect lung cancer in the breath of cancer sufferers with 99 percent accuracy. The study was based on well-established concepts. It has been known since the 80's that tumors exude tiny amounts of alkanes and benzene derivatives not found in healthy tissue. Other researchers have shown that dogs, whose noses can pick up odors in the low parts-per-billion range, can be trained to detect skin cancers or react differently to dried urine from healthy people and those with bladder cancer, but never with such remarkable consistency. The near-perfection in the clinic's study, as Dr. Donald Berry, the chairman of biostatistics at M. D. Anderson Cancer Center in Houston, put it, "is off the charts: there are no laboratory tests as good as this, not Pap tests, not diabetes tests, nothing." Copyright 2006 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 8403 - Posted: 01.17.2006

By JOHN SCHWARTZ For Belding's ground squirrels, it's a smell world, after all. New research reveals at least five sources of body scent that the squirrels, Spermophilus beldingi, use as a symphony of smell to identify one another. Individual identification is important, said Jill M. Mateo, an assistant professor in the department of comparative human development at the University of Chicago and the author of the study. The squirrels can live a decade or more and dwell in high density. They develop distinctive personalities, laid back or cantankerous, so "it pays to be able to know who's who," Dr. Mateo said. Other scientists have studied the many ways social animals identify one another, and research by Robert E. Johnston of Cornell has yielded similar results with hamsters. Copyright 2006 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 8402 - Posted: 01.17.2006

By Gregory Mott If recent reports are to be believed, those sleek iPod earbuds may carry risks beyond marking wearers as mugger-bait. As if to rain on Apple's holiday parade -- the company reported sales of 14 million iPods in the last quarter of 2005, bringing total sales for the product to more than 42 million -- audiologists and other hearing experts have been issuing warnings in recent weeks that improper use of iPods and other personal stereo systems can dramatically heighten risk of hearing loss, particularly in young people. Is this just a case of advocacy groups seizing upon a teachable moment to fly their banners -- or is there really a chance that being able to hold your entire music library in your palm can come at the cost of your hearing? Time for a reality check. Audiology experts agree that hearing loss is increasing in the United States. According to widely cited figures from the American Speech-Language-Hearing Association (ASHA), the number of Americans age 3 and older with some form of auditory disorder has more than doubled since 1971, from 13.2 million to about 30 million today. Of those, one-third are said to be people with noise-induced hearing loss. © 2006 The Washington Post Company

Keyword: Hearing
Link ID: 8401 - Posted: 06.24.2010

This column is brought to you care of what the Australians call a "shonky molly-dooker." Not so much a left-hander as a leftish-hander. What I do is write and draw with my left hand but approach everything else the – ha-ha – right way. This anomaly has led me, over the years, to pay more than passing attention to what you might call the science of left-handedness. If it can find a believable explanation for why shonky molly-dookerness should persist in human evolution, maybe an extension of that reasoning will tell me something essential about myself. That's why my eyes opened when I started to read a recent paper published in the journal Brain by Sandra Witelson and her colleagues at McMaster University. They were interested in coming up with an as accurate as possible measure of the relationship of brain size to braininess. They approached people dying of cancer in a Hamilton hospital and asked whether they would take IQ tests. Afterwards, the scientists did an autopsy on the brains to see how volume compared with IQ score. The test group was divided between men and women and right- and left-handers. The handedness was measured because previous evidence has accumulated that there might be relationship between handedness and brain size. © CBC 2006

Keyword: Laterality; Intelligence
Link ID: 8400 - Posted: 06.24.2010

Every morning, sometime between packing four school lunches, sorting through hats and mittens, and making sure her kids' homework is in order, Luanne Hughes takes a light shower. For thirty minutes 38-year-old Hughes basks in the rays of a 10,000 candlepower light. Hughes is among an estimated four to six percent of Americans that develop seasonal affective disorder, a type of depression that sets in as the winter days grow short. People who develop seasonal affective disorder, also aptly known as SAD, begin to have trouble getting out of bed in the morning, they lose interest in social activities, tend to withdraw, and generally feel lackluster and blue. Other statistics suggests that up to 20 percent of Americans develop minor symptoms of SAD each winter. Hughes says her daily light shower is a way she can literally brighten her mood without relying on medications. "I just don't like being on drugs," she says. Light therapy is well established as a treatment for SAD. But doctors now have new recommendations for when SAD patients should receive light therapy. Columbia University psychologist and a leading SAD expert Michael Terman, and his colleague and wife Jiuan Su Terman, reported in the journal CNS Spectrums that SAD patients should time their daily dose of light therapy — ideally thirty minutes in front of a 10,000-lux light — according to their own biological clocks. © ScienCentral, 2000-2006.

Keyword: Depression; Biological Rhythms
Link ID: 8399 - Posted: 06.24.2010

Helen Pearson The appetite-control hormone leptin staves off symptoms of stress in rats, and might lead to new ways to fight human depression, say researchers in the United States. Leptin is famed for controlling our weight and appetite. But the hormone, which is released by fat cells and gives the brain a reading of our fat stores, is also thought to act in brain areas involved in emotion. To explore this link, Xin-Yun Lu and her colleagues at the University of Texas Health Science Center in San Antonio stressed rats by, for example, separating them from other animals. The rats' leptin levels plunged at the same time that they showed behavioural changes such as losing interest in a sugary drink, the kind of apathy that is often associated with human depression. The team found that injections of leptin into otherwise healthy animals were as good as at least one known treatment in a test widely used to screen for new antidepressants. In this test, the researchers showed that leptin could help the animals to evade depression-induced behaviour when forced to swim. ©2006 Nature Publishing Group

Keyword: Depression; Obesity
Link ID: 8398 - Posted: 06.24.2010

Regular exercise may reduce the risk of dementia and Alzheimer’s disease in the elderly by as much as 40%, according to a new study. And the effect is even more pronounced for those who are more frail, say the researchers. The US team, at Group Health Cooperative in Seattle, studied a group of 1740 people aged 65 or over, all of whom began the study with good cognitive function. The participants reported how many days per week they had exercised for 15 minutes or more, in activities varying from walking to callisthenics to swimming. Their physical function was also recorded, including grip strength and walking speed. Each was evaluated again every two years and tests were performed to determine whether they had developed dementia. After six years, 158 people in the group had developed dementia, and 107 of these had Alzheimer’s. But those who had exercised at least three times a week were on average 38% less likely to have developed dementia than those exercising less than three times a week. "Those who had scored the lowest on the physical function tests, showed the most marked reduction in risk of dementia if they exercised,” says Paul Crane, one of the research team, from the University of Washington in Seattle. Amongst those with good levels of exercise, “people who scored 10 out of 16 in the physical tests had an average 42% reduction in risk of dementia, compared to 25% for those who scored 12 out of 16." © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 8397 - Posted: 06.24.2010