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By MARY DUENWALD By April 12, ephedra will disappear from stores and Web sites that sell dietary supplements, by order of the Food and Drug Administration. But that does not mean the herb will entirely drop out of sight. The agency's ban on ephedra specifically excludes uses of the herb in traditional Asian medicine. Acupuncturists, herbalists and other practitioners of Oriental medicine routinely dispense teas, pills and powders containing ma huang, the type of ephedra grown in China, to treat colds, asthma, persistent cough, headache, water retention and other maladies. The ban on dietary supplements containing ephedra, announced in December, was published by the agency on Wednesday and will take effect 60 days later. It targets the ephedra supplements that have been advertised for weight loss, muscle building and athletic performance. Copyright 2004 The New York Times Company
Keyword: Obesity
Link ID: 4995 - Posted: 02.18.2004
With federal indictments handed out over the weekend in an illegal steroid distribution scheme, professional sports is under scrutiny. Eager to emulate their favorite athletes, as many as 1 in 18 teens may have tried steroids. But at what cost? This ScienCentral News video takes a closer look. Anabolic steroids, sometimes called "roids," are synthetic derivatives of the male hormone testosterone. They are used to increase muscle mass and strength, and they are illegal. But that hasn't stopped teens from using them. In a culture obsessed with physical fitness and the pursuit of the perfect body the pressure's on to obtain the ideal. Surf the web, flip through a magazine, turn on the TV— these mediums are saturated with images of rippling muscles and six-pack abs. According to Dr. Linn Goldberg, head of the Division of Health Promotion and Sports Medicine at Oregon Health and Science University, the media has played an even more direct role in promoting steroids. He explains that the term "on steroids" is used to sell everything from cars to computers to post-it notes, and that "on steroids" is implied to be a good thing, denoting "bigger, better and faster." "You would never say something was 'on heroin'," he says. © ScienCentral, 2000-2003.
Keyword: Drug Abuse; Hormones & Behavior
Link ID: 4994 - Posted: 06.24.2010
NewScientist.com news service Women judge the attractiveness other women more harshly when at their most fertile, suggests a new study. The phenomenon could be a strategy to devalue potential rivals, says the psychologist behind the work - being bitchy about others could help a woman win the attention of a desirable man. Theories of sexual selection in most species usually concentrate on how males compete for females. But recent theories for humans suggest there is intrasexual competition among females as well, as males can vary markedly in their abilities as providers and protectors. Maryanne Fisher, a psychologist at York University in Toronto, Canada, decided to try to find evidence for female competition by presenting heterosexual students with photos of faces. She found that when women were in the most fertile phase of their menstrual cycles, they rated the attractiveness of other women lower than when they were not. © Copyright Reed Business Information Ltd.
Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 4993 - Posted: 06.24.2010
Two-pronged approach synergizes growth BOSTON -- Researchers at Children's Hospital Boston and Harvard Medical School have advanced a decades-old quest to get injured nerves to regenerate. By combining two strategies – activating nerve cells' natural growth state and using gene therapy to mute the effects of growth-inhibiting factors – they achieved about three times more regeneration of nerve fibers than previously attained. The study involved the optic nerve, which connects nerve cells in the retina with visual centers in the brain, but the Children's team has already begun to extend the approach to nerves damaged by spinal cord injury, stroke, and certain neurodegenerative diseases. Results appear in the February 18th Journal of Neuroscience. Normally, injured nerve fibers, known as axons, can't regenerate. Axons conduct impulses away from the body of the nerve cell, forming connections with other nerve cells or with muscles. One reason axons can't regenerate has been known for about 15 years: Several proteins in the myelin, an insulating sheath wrapped around the axons, strongly suppress growth. Over the past two years, researchers have developed techniques that disable the inhibitory action of myelin proteins, but this approach by itself has produced relatively little axon growth.
Keyword: Regeneration
Link ID: 4992 - Posted: 06.24.2010
A new imaging technique used by a group of researchers at the University of Washington and elsewhere has revealed a previously unknown cellular structure in the retinas of mice. The structure is the site for an important part of the retinoid cycle, a chemical process critical to vision, the scientists said. Results of their study, which took more than three years, appeared in the Feb. 2 issue of the Journal of Cell Biology. Dubbed a retinosome, the newly discovered organelle houses retinyl esters, which are an intermediate chemical product in the retinoid cycle. That cycle is critical in the regeneration process for 11-cis-retinal, a light-absorbing chemical vital to vision. Dr. Yoshikazu Imanishi, senior research fellow in the UW Department of Ophthalmology, worked on the project with Dr. Kris Palczewski, Bishop Professor and professor of ophthalmology, chemistry, and pharmacology at the UW; Matthew Batten, a research scientist in Palczewski's lab; and researchers from Vanderbilt University and the University of Utah.
Keyword: Vision
Link ID: 4991 - Posted: 02.18.2004
In some cultures, pointing is a faux pas, sometimes even insulting. New research is turning this social don't on its head, showing that hand gestures, such as pointing, can enhance the understanding of messages. While describing portraits, participants in a study who used referential gesturing were better able to identify targets and reduce verbal cues than participants who only relied on verbal directions. The findings will be published in the June issue of Psychological Science, a journal of the American Psychological Society. The author of the report is Adrian Bangerter, Université de Neuchâtel. Bangerter sought to identify how referential (pointing) gestures contribute to understanding in conversation. Pointing is often thought to be used to identify a specific object of a verbal cue (e.g., pointing and saying "that's John" identifies the referent of the word "that"). In contrast, the experiment explored the possibility that pointing could be used to focus the audience's gaze on a particular subregion of shared visual space, thus facilitating the use of verbal descriptions.
Keyword: Language
Link ID: 4990 - Posted: 02.18.2004
Medical experts say a new device which allows spirits to be inhaled could lead to brain damage. Bristol bar, Il Bordello, is believed to be the first in the country to use the Alcohol Without Liquid vaporiser. Professor Oliver James, from Newcastle University, said: "This will not only make you very drunk very quickly but is also likely to increase the risk of direct alcohol damage to the brain." Inventor Dominic Simler said the device would reduce the effects of hangovers. Professor James, who is head of clinical medical sciences at the university, said: "This could do irreversable damage to the nerves, lead to swelling and possibly lead to dementia in the long term." He added that people may be able to use the device to inhale alcohol for 20 minutes and still be able to pass a police breathalyser test. (C)BBC
Keyword: Drug Abuse
Link ID: 4989 - Posted: 02.17.2004
By JANE E. BRODY So, I was wrong. You may not have to drink eight glasses of water a day to be well hydrated, and you can count caffeinated beverages in your total water intake, according to a new report from the Institute of Medicine, the group that sets desirable levels of nutrient intake for Americans of all ages. The report, issued last week, reviewed the status of water, salt and potassium consumption by Americans and Canadians and set desirable intake levels for these nutrients. Copyright 2004 The New York Times Company
Keyword: ADHD
Link ID: 4988 - Posted: 02.17.2004
By RICHARD A. FRIEDMAN, M.D. At 45, my patient Bruce was at the pinnacle of his career, with a lucrative law practice. Then his life was cruelly turned upside down by two medical events, a crushing first episode of major depression and a series of strokes from untreated hypertension. For many years, Bruce struggled with severe depression and high blood pressure without much headway. Then something strange happened. He suddenly pulled out of the depression and dove into his work. Not only that, but he felt the surge of energy and self-confidence that he used to have. No hurdle seemed too high or problem unsolvable, he recently recalled. Copyright 2004 The New York Times Company
Keyword: Development of the Brain; Schizophrenia
Link ID: 4987 - Posted: 02.17.2004
By DONALD G. McNEIL Jr. A new form of mad cow disease has been found in Italy, according to a study released yesterday, and scientists believe that it may be the cause of some cases of human brain-wasting disease. While the strain has been found in only two Italian cows, both apparently healthy, scientists in Europe and the United States said it should provide new impetus in Washington for the Department of Agriculture to adopt the more sensitive rapid tests used in Europe because it may not show up in those used in the United States. Along with the Italian study, there have been recent reports of unusual types of mad cow disease in France and Japan, and scientists say the discovery of new forms suggests that many cases of "sporadic" human disease — by far the most common kind, responsible for about 300 deaths a year in the United States — are not spontaneous at all, but come from eating animals. Copyright 2004 The New York Times Company
Keyword: Prions
Link ID: 4986 - Posted: 06.24.2010
SEATTLE--A simple cocktail of vitamins and supplements can significantly slow the loss of brain function associated with aging in dogs, according to new research presented here 15 February at the annual AAAS meeting. The findings could have implications for delaying or preventing Alzheimer's disease in humans. Aging dogs suffer from a loss of memory and learning ability similar to that seen in humans who go on to develop Alzheimer's disease. Canine brains also accumulate plaques made of b-amyloid, the destructive protein fragments believed to be associated with Alzheimer's in humans, making dogs a useful model for studying the disease. Previously, neurobiologist Carl Cotman of the University of California, Irvine, and his colleagues tested the cognitive abilities of older beagles that had been given a combination of vitamins C and E, a few fruits and vegetables, and alphalipoic acid and acetylcarnitine, two compounds normally present in low levels in the body that reduce the production of free radicals thought to be involved in Alzheimer's disease. They found that the mixture boosted the learning and memory skills of the dogs relative to similarly aged dogs that hadn't taken the supplements. Copyright © 2004 by the American Association for the Advancement of Science.
Keyword: Alzheimers
Link ID: 4985 - Posted: 06.24.2010
NewScientist.com news service Half of all human languages will have disappeared by the end of the century, as smaller societies are assimilated into national and global cultures, scientists have warned. Losing this linguistic diversity will be a blow not only for cultural studies but also for cognitive science, they say. The only option is to record and catalogue these languages before they disappear for good, say the researchers, who gathered at the American Association for the Advancement of Science in Seattle, Washington, to issue the warning. Some 6800 "unique" languages are thought to exist today. But social, demographic and political factors are all contributing to the rapid disappearance of many mother tongues. © Copyright Reed Business Information Ltd.
Keyword: Language
Link ID: 4984 - Posted: 06.24.2010
A fruit fly gene called radish, and the newly identified protein it encodes, have opened doors to understanding the genes and neuronal networks that govern a special type of memory, termed anesthesia-resistant memory. Researchers had previously known that for most animals -- not just humans -- loss of consciousness from anesthesia causes amnesia for recently experienced events. In contrast, for reasons that are not well understood, older memories are resistant to the effects of anesthesia. With the help of model organisms such as Drosophila, different types of memory are also now beginning to be identified on the basis of genetic requirements. This week, new analysis of a fly gene required for anesthesia-resistant memory sheds light on the nature of this memory type, and what makes it different from other kinds of stable memories. The new work, reported by Josh Dubnau and colleagues at Cold Spring Harbor Laboratory in New York, was based on some well established observations regarding learning and memory in the fruit fly. In Drosophila, memory of an odor-electric shock association is at first easily erased by anesthesia-induced loss of consciousness. Within the first hour after this memory forms, however, it becomes more resistant to anesthesia. For over a decade, memory researchers have known that this form of memory, anesthesia-resistant memory, does not form in a mutant strain of flies bearing a mutation in the gene called radish. Until now, however, the molecular basis for the radish memory defect has been a mystery.
Keyword: Learning & Memory
Link ID: 4983 - Posted: 02.17.2004
CHAMPAIGN, Ill. -- Aging adults who give up a sedentary lifestyle and replace it with a cardiovascular fitness regimen as simple as brisk walks reap greater focus and reduced decision-making conflict as they perform a variety of tasks, scientists say. That conclusion comes from a study that utilized functional magnetic resonance imaging to measure changes in brain activity in adults ranging in age from 58 to 78 before and after a six-month program of aerobic exercise. The study, done at the University of Illinois at Urbana-Champaign, is scheduled to appear the week of Feb. 16-20 as part of PNAS Online Early Edition, ahead of regular print publication in the Proceedings of the National Academy of Sciences. Scientists, led by Arthur F. Kramer, a professor of psychology and researcher at the Beckman Institute for Advanced Science and Technology at Illinois, identified specific functional differences in the middle-frontal and superior parietal regions of the brain that changed with improved aerobic fitness. These changes allowed researchers to predict improvements in performance on a decision-making task.
Keyword: Alzheimers
Link ID: 4982 - Posted: 02.17.2004
Is being a worry wart actually more of a risk to your health than being a daredevil? Sonia Cavigelli, a behavioral scientist at the University of Chicago, studied this in rats and found that the fearful ones often age prematurely and die younger than their brave counterparts. "We were interested in identifying individual differences in how animals respond to stress," says Cavigelli. "And the way to best do that is to look at their stress hormones. And those are circulating in the bloodstream, and so we can measure those directly from the bloodstream." When we are in stressful situations, our bodies make hormones such as cortisol http://stress.about.com/cs/cortisol/a/aa012901.htm that help us take action. "If we have some sort of challenge in life, these stress hormones actually help us produce energy that we can use, and energy that's available immediately," explains Cavigelli. "So, if you're in a challenging situation, for example, the stress hormones help you respond to that challenge by giving you the energy necessary." Cavigelli and her colleagues studied fourteen pairs of brother rats, each pair consisting of one brave rat and one scared rat. She introduced these rats, at three different times in their lives, to new and unfamiliar stimuli, such as the addition of a tunnel or a brick to their exploration area. She videotaped how each animal dealt with these changes to their environments, and monitored their hormone levels. © ScienCentral, 2000-2003.
Scientists have created an unlimited supply of a type of nerve cell found in the spinal cord – a self-renewing cell line that offers a limitless supply of human nerve cells in the laboratory. Such a supply has long been one goal of neurologists anxious to replace dead or dying cells with healthy ones in a host of neurological diseases. In this study, appearing in the March issue of Nature Biotechnology, the scientists then used the cells to partially repair damaged spinal cords in laboratory animals, re-growing small sections of the spinal cord that had been damaged. Doctors emphasize that tests in people with damaged spinal cords or other neurological conditions are a long ways off. The researchers, led by neurologist Steven Goldman, M.D., Ph.D., of the University of Rochester Medical Center, created the unique cells by introducing a gene called telomerase, which is responsible for the ability of stem cells to live indefinitely, into more specialized "progenitor" cells. In normal development, these progenitor cells give rise to very specific types of spinal neurons, but they do so for only short periods of time, because they lack the ability to continuously divide. With the newly added telomerase gene, the spinal progenitor cells were able to continuously divide while still producing only specific types of neurons. The outcome was a line of immortal progenitor cells, capable of churning out human spinal neurons indefinitely.
Keyword: Stem Cells; Regeneration
Link ID: 4980 - Posted: 06.24.2010
The ability to develop a form of communication that becomes an actual language is apparently innate, new University of Chicago research on the use of gestures among deaf children and experiments with adults shows. Psychologist Susan Goldin-Meadow's work with adults and children also shows which features of language seem to come more easily, and are therefore resilient, such as using order to convey who does what to whom. Her research also shows which characteristics are more difficult to develop, particularly without linguistic input. She has found that youngsters inventing their own sign language do not form verb tenses, for instance. Her previous work has shown that deaf children of non-deaf adults develop a language-like system of gestures to communicate. To explore further how gestures become a language, Goldin-Meadow and her colleagues tested hearing adults. They found that adults told to use their hands rather than their mouths to communicate developed gestures and organized them into a syntax similar to that used by the deaf children.
Keyword: Language
Link ID: 4979 - Posted: 02.16.2004
Chemicals that block brain receptors for a key neurotransmitter make it harder for people to learn new information WASHINGTON -- New evidence clarifies how the only government-approved treatments for mild-to-moderate Alzheimer's Disease may work to improve symptoms. When scientists chemically blocked receptors for an important neurotransmitter called acetylcholine, even healthy young people found it significantly harder to learn and remember – especially in the face of interference. This finding may shed light on how cholinesterase inhibitors, FDA-approved drugs that slow the breakdown of acetylcholine in Alzheimer's patients, help alleviate dementia symptoms. The study appears in the February issue of Behavioral Neuroscience, which is published by the American Psychological Association (APA). The study demonstrated that acetylcholine helps keep old information from interfering with our ability to learn and remember new information. The findings may help to explain why conditions associated with lower levels of acetylcholine in the brain, such as Alzheimer's disease, Parkinson's disease, dementia due to multiple strokes, multiple sclerosis and schizophrenia cause problems with memory function, as well as the hallucinations and delusions that can occur in some of these conditions.
Keyword: Alzheimers
Link ID: 4978 - Posted: 06.24.2010
Individual differences in alcohol response – ranging from sleepy to social, sad to happy – have a tremendous influence on a person's risk for developing alcohol dependence. Researchers already know that many of the psychological, physiological, and behavioral effects of alcohol are determined by the central nervous system and related neurotransmitter activity, although beliefs about the effects of drinking alcohol are also important. Symposium proceedings published in the February issue of Alcoholism: Clinical & Experimental Research present evidence for how genetic variation may influence neurotransmitter activity, thereby having an effect on alcohol sensitivity and subsequent behaviors. "Activities of neurons, which are specialized cells of the nervous system, influence the release of neurochemicals that cause increases or decreases in brain activity," said Kim Fromme, symposium organizer and associate professor of psychology at The University of Texas at Austin. "Virtually everything we think, feel, sense, and do are determined by activity of these neurochemicals and their related neuronal activity in the brain. Approximately 100 different neurochemicals have been identified, and many of them have been found to be affected by alcohol." Four presentations were given during the symposium at the June 2003 Research Society on Alcoholism meeting in Fort Lauderdale, Florida. Presenters combined human genotyping with laboratory measures of behavior and subjective reports in order to "match" individuals' genetic makeup with the behavioral effects that people experience and exhibit due to alcohol.
Keyword: Drug Abuse; Genes & Behavior
Link ID: 4977 - Posted: 06.24.2010
Pictures of diseased organs and rotting teeth could feature on cigarette packets under new government plans. Similar pictures appear in Canada, Thailand, Brazil and Singapore - now a public consultation will be held on whether to introduce them in the UK. "We need to continue with fresh, hard-hitting ideas, providing more information that will help smokers quit," Health Secretary John Reid said. The announcement comes one year after a total ban on tobacco advertising. Larger, more direct warnings have been used on cigarette packets since last September. But research in Canada has suggested that graphic images of diseased organs grab smokers' attention and make people more likely to quit. (C)BBC
Keyword: Drug Abuse
Link ID: 4976 - Posted: 02.15.2004


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