It’s estimated that at least 4.5 million U.S. adolescents are cigarette smokers. Each day, nearly 4,800 teens smoke their first cigarette, and nearly 2,000 of them will become regular smokers. That’s almost two million annually. “Of all the people alive in this world today, we expect half a billion will be killed by cigarette smoking—two-thirds in poor countries,” Greg Connolly director of the Tobacco Control Program at the Massachusetts Department of Public Health, told PBS’s NOVA. “And of those two-thirds, half are children under the age of 18.” Now some teenagers are smoking cigarettes they perceive to be safer than conventional ones—additive-free cigarettes, and hand-rolled unfiltered cigarettes from India called bidis. Bidis, which are wrapped in tendu leaves, are especially appealing to teens because they are cheaper than regular cigarettes, and come in flavors like strawberry, chocolate, and black licorice. © ScienCentral, 2000-2003.

Keyword: Drug Abuse
Link ID: 3840 - Posted: 06.24.2010

Maybe you really are what you eat. This would solve the long-time mystery of why so many of Guam's Chamorro people – up to a third per village -- suffered a devastating neurological disease. A new study suggests that they gorged on flying fox bats that in turn had feasted on neurotoxin-laden cycad seeds. "Through the consumption of cycad-fed flying foxes, the Chamorro people may have unwittingly ingested large quantities of cycad neurotoxins," say Clark Monson of the University of Hawaii, Honolulu, Sandra Banack of California State University, Fullerton, and Paul Cox of the National Tropical Botanical Garden in Kalaheo, Hawaii, in the June issue of Conservation Biology. Guam's indigenous Chamorro people historically had a high incidence of a neurological disease with similarities to Lou Gehrig's, Parkinson's and Alzheimer's diseases. Called ALS-PDC (amyotrophic lateral sclerosis-Parkinsonian dementia complex), the disease's symptoms range from muscle weakness and paralysis to dementia. The rate of ALS-PDC has been as much as 100 times higher in Guam's Chamorro people than in the continental U.S.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 3839 - Posted: 06.24.2010

Brain changes that occur with cocaine use and the tendency toward relapse may be reduced by a behavioral treatment using extinction training--a form of conditioning that removes the reward associated with a learned behavior. NIDA-funded researchers found that extinction training during cocaine withdrawal produces changes in brain receptors for glutamate, a brain chemical found in the nucleus accumbens, the reward center of the brain. A reduction in glutamate input from cortical brain regions by chronic cocaine use is thought to contribute to persistent cravings for the drug. The researchers trained rats to self-administer cocaine by pressing a lever and to associate the availability of cocaine with certain environmental cues (lights and noise). Once the rats had learned to expect cocaine when they pressed the lever, cocaine and the cues were removed so that the rats did not receive the cocaine that they were anticipating. One group of rats received this extinction training during cocaine withdrawal while another group did not receive the training. After extinction training was over, the researchers exposed the rats to the cocaine-associated cues and administered cocaine to induce relapse.

Keyword: Drug Abuse
Link ID: 3838 - Posted: 05.24.2003

When it comes to tolerating spicy foods, not all mouths are created equal. Findings published today in the journal Science help explain why that is the case. Researchers have identified a lipid molecule that plays a critical role in controlling the severity of a burning sensation. Scientists have known for some time that it is a compound known as capsaicin that gives chili peppers their kick. In the mouth, the capsaicin receptor (TRPV1) governs the level of pain that can accompany a spicy meal. Elizabeth D. Prescott and David Julius of the University of California, San Francisco, investigated a specific binding site within TRPV1. They discovered that a lipid molecule known as PIP2 is usually bound to the receptor, but in the presence of capsaicin, it is released, creating a painful sensation. The strength with which PIP2 is bound to TRPV1, the researchers found, thus determines how sensitive the neurons are to the spice. © 1996-2003 Scientific American, Inc.

Keyword: Pain & Touch; Chemical Senses (Smell & Taste)
Link ID: 3837 - Posted: 06.24.2010

Butterfly flight simulator sheds light on epic migration During their winter migration to Mexico, monarch butterflies depend on an internal clock to help them navigate in relation to the sun, scientists have found. By studying monarchs inside a specially designed flight simulator, the researchers have gathered what they believe is the first direct evidence of the essential role of the circadian clock in celestial navigation. The study appears in the journal Science, published by the American Association for the Advancement of Science (AAAS). In the fall, monarch butterflies journey from central and eastern North America to a small region in central Mexico. Only every fourth or fifth generation makes the trip, indicating that the urge to migrate is instinctive, rather than learned.

Keyword: Biological Rhythms; Animal Migration
Link ID: 3836 - Posted: 05.23.2003

St. Louis, — Scientists at Washington University School of Medicine in St. Louis have gained new insights into the causes of human deafness and balance disorders by studying the inner ear of chickens. The research provides new clues as to why birds can replace critical cells in the inner ear and humans cannot. Loss of these so-called sensory hair cells in humans is a leading cause of deafness and impaired balance due to aging, infectious disease and exposure to loud noise. The study will be published in the June 1 issue of the journal Human Molecular Genetics and appears online today. The team measured the activity of more than 1,800 genes in sensory cells from two regions of the chicken inner ear: the cochlea, where sound is converted into nerve impulses, and the utricle, where balance is sensed. The utricle of birds replaces sensory cells regularly, while the cochlea replaces them when they die. The investigators discovered more than 100 significant differences between the two regions.

Keyword: Hearing
Link ID: 3835 - Posted: 06.24.2010

Hints emerge that doomed jab did some good. HELEN PEARSON A controversial vaccine may stall Alzheimer's disease, despite having serious side-effects, new research suggests. The study revives optimism that a tweaked version of the shot could reach the clinic. Early hopes for the vaccine died in January 2002, when a handful of patients in a clinical trial of the treatment developed brain inflammation. The results forced Elan, the Dublin-based company behind the vaccine, to stop the tests. Now a team led by Roger Nitsch of the University of Zurich in Switzerland has released the first data on how patients fared after immunization. Independently of Elan, the researchers monitored 30 patients in the clinical trial after it stopped1. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Alzheimers
Link ID: 3834 - Posted: 06.24.2010

CHAPEL HILL -- Adults with attention-deficit-hyperactivity disorder treated long term with an extended-release mixed-salts amphetamine medication maintained significant symptom improvement with good tolerance, a new study shows. University of North Carolina at Chapel Hill researchers presented the study results - from one of the largest trials ever conducted of adult ADHD - today (May 21) at the American Psychiatric Association annual meeting, the world's largest psychiatric conference. "ADHD is not just a childhood disorder. While hyperactivity may sometimes diminish by adulthood, inattention and impulsivity often remain," said Dr. Richard H. Weisler, adjunct professor of psychiatry at UNC's School of Medicine.

Keyword: ADHD
Link ID: 3833 - Posted: 05.22.2003

An enzyme crucial to formation of Alzheimer’s plaques and tangles may hold promise as a target for future medications, suggest studies in mice and cells. By blocking the enzyme, lithium stems the accumulation of beta amyloid, which forms Alzheimer’s plaques, scientists funded by the National Institutes of Health (NIH) report in the May 22, 2003 Nature. Inhibiting the enzyme, glycogen synthase kinase — 3 alpha (GSK-3 alpha), also blocks formation of neurofibrilary tangles by the tau protein. “Although widely used to treat bipolar disorder, lithium’s propensity to cause side-effects may limit its use in older people, who are more susceptible to Alzheimer’s disease,” cautioned Peter Klein, M.D., University of Pennsylvania School of Medicine, who led the research team, which was funded by the National Institute of Mental Health (NIMH) and the National Institute on Aging (NIA). It will also be important to develop “new agents” that specifically target GSK-3 alpha, he added. To pinpoint the enzyme’s role in the formation of amyloid plaques, the researchers first treated cells expressing the amyloid precursor protein with lithium, which they had earlier shown blocks GSK-3. Therapeutic doses of lithium inhibited the production of beta amyloid. Another GSK-3 inhibitor, structurally unrelated to lithium, also reduced production of beta amyloid, as did blocking expression of the GSK-3 alpha protein. Likewise, raising GSK-3 alpha levels enhanced beta amyloid production. These experiments established that the enzyme is required for maximal amyloid processing.

Keyword: Alzheimers
Link ID: 3832 - Posted: 06.24.2010

COLUMBUS, Ohio -- Musicians who hear the music they are performing while learning a new piece have a better memory for the music later, a new study suggests. But after they learn a song, actually hearing the music as they play does not improve the accuracy of their performance. These results shed new light on how memory works and on theories about how people learn, said Caroline Palmer, co-author of the study and professor of psychology at Ohio State University. Specifically, Palmer said the findings cast doubt on the universality of matching theories – theories that state memory works best when conditions are similar during learning and during recall of the information.

Keyword: Hearing; Learning & Memory
Link ID: 3831 - Posted: 06.24.2010

ST. PAUL, MN - Public education is needed about the symptoms and risks of mini-stroke, also called transient ischemic attack or TIA, according to the first large study on the topic, which is published in the May 13 issue of Neurology, the scientific journal of the American Academy of Neurology. The study found that only 9 percent of people could give the definition of a TIA or identify a symptom of TIA. TIA symptoms are the same as those for a regular stroke, but TIA symptoms resolve themselves within 24 hours. The phone survey of more than 10,000 people found that 3.2 percent had TIA symptoms but never saw a physician about them. Among those with a TIA diagnosis, 16 percent saw the doctor more than a week after the symptoms occurred. “People think that because these symptoms go away quickly, they don’t need to worry about them, but that’s definitely not the case,” said study author and neurologist S. Claiborne Johnston, MD, PhD, of the University of California, San Francisco. “People who’ve had a TIA are at high risk of having a stroke, particularly in the first few days after the TIA, and doctors can help them reduce that risk. ”

Keyword: Stroke
Link ID: 3830 - Posted: 06.24.2010

A whole lot of shaking helps bring your eyes into sharp focus By Eric Haseltine Your brain cells are sometimes like hyperactive children that get bored quickly. For instance, without a constant change of scenery, neurons in your visual system will literally tune out incoming information in search of fresh stimulation. Fix your gaze on the black "eye" in the center of Figure A for 20 seconds, while trying not to blink. After six or seven seconds, the dotted circle will begin to fade in and out of your awareness. Called Troxler fading, for Ignaz Paul Vital Troxler, a Swiss scientist who described the phenomenon in 1804, the effect is believed to be caused by a rapid decrease in the eye's response to images that are stabilized on the retina. Notice that if you scan your eyes back and forth across the black eye, causing slight shifts in the images on your retinas, the dotted circle will not vanish. © Copyright 2003 The Walt Disney Company

Keyword: Vision
Link ID: 3829 - Posted: 06.24.2010

By CLIFFORD KRAUSS with SANDRA BLAKESLEE VANCOUVER, British Columbia, — Mad cow disease was diagnosed in a cow in Canada today, and United States health authorities immediately placed a ban on imports of beef, cattle and animal feed from Canada. The report shocked ranchers through much of western Canada, where trading in livestock was immediately halted because of plummeting cattle prices. The shock waves spread through the financial markets, where prices in many Canadian and American meat and restaurant companies fell sharply. Canadian authorities stressed that only one cow out of Canada's total cattle population of 3.6 million was found to be sick and there was no immediate evidence that the disease had spread among livestock or humans. Copyright 2003 The New York Times Company

Keyword: Prions
Link ID: 3828 - Posted: 06.24.2010

--- Using a laser range-finder, neurobiologists have scanned real-life scenes to gather millions of distance measurements to surfaces in each scene -- analyzing the mass of data to explain a series of long-known but little-understood quirks in how people judge distances. The measurements reveal, for example, that the tendency of people to estimate the distance of isolated objects as being six to 12 feet away arises because that is the average distance of actual objects and surfaces in the visual scenes people encounter. Thus, said the Duke University Medical Center neurobiologists, the findings support their theory that the visual system has evolved to make the best statistical guess about distances and other features of visual scenes, based on past experience. Copyright © 1992-2003 Bio Online, Inc.

Keyword: Vision
Link ID: 3827 - Posted: 06.24.2010

Symptoms may pose risk to fetus, raise chance of post-partum depression ANN ARBOR, MI – One in five pregnant women may be experiencing symptoms of depression, but few are getting help for it, a new University of Michigan study finds. And those with a history of depression any time before their pregnancy -- about one in every four women -- are about twice as likely as other women to show signs of depression while pregnant, the study results show. The results reveal troubling under-diagnosis and under-treatment of depression in pregnancy. Twenty percent of the women scored high on a standard survey of depression symptoms, but of those, only 13.8 percent were receiving any mental health counseling, drugs or other treatment. Only about 24 percent of those who had had depression in the last six months were receiving treatment during pregnancy.

Keyword: Depression; Hormones & Behavior
Link ID: 3826 - Posted: 06.24.2010

Scientists at The Scripps Research Institute (TSRI) have designed a new way to make vaccines against drugs of abuse that could become a valuable tool for treating addiction by helping the body clear the drug from the bloodstream. The latest vaccine they created using this approach induces the body to clear nicotine. "These new vaccines greatly suppress the reinforcing aspects of the drug," says principal investigator Kim D. Janda, Ph.D. "Blocking it before it gets to the brain--that's the key."

Keyword: Drug Abuse
Link ID: 3825 - Posted: 05.21.2003

Results presented at APA Wilmington, Del/San Francisco –- An analysis of two studies presented today at the 156th annual meeting of the American Psychiatric Association (APA) examined the use of quetiapine fumarate as a monotherapy for acute mania in patients suffering from bipolar disorder. Pooled results from two 12-week clinical trials involving more than 600 patients showed that 48.1% of patients treated with quetiapine fumarate achieved a response [defined as >50% decrease from baseline YMRS (Young Mania Rating Scale) score], compared with 31.3% of those given placebo. The data presented are among the first to evaluate the efficacy, tolerability and safety of quetiapine fumarate as a monotherapy treatment for acute mania associated with bipolar disorder.1 The studies presented are from two of three Phase III trials that supported AstraZeneca's (AZN: NYSE) Supplemental New Drug Application (sNDA) for quetiapine fumarate, in the adjunctive and monotherapy treatment of acute mania associated with bipolar disorder. The sNDA for quetiapine fumarate was submitted to the U.S. Food & Drug Administration in December 2002. Quetiapine fumarate is currently indicated for the treatment of schizophrenia in adults.

Keyword: Schizophrenia; Depression
Link ID: 3824 - Posted: 06.24.2010

Exclusive from New Scientist Print Edition The remarkable visual vocabulary of cuttlefish, which change the colour of their skin in a flash for communication or camouflage, is being catalogued with the help of a mathematical technique borrowed from signal processing. Independent component analysis (ICA) was invented to untangle mixtures of signals. For example, it can pick out individual voices from the babble of a crowd. Now cuttlefish expert Daniel Osorio and his colleagues from the University of Sussex in Britain are hoping it can help them work out which basic elements cuttlefish use to build up their sophisticated patterns. They called in neuroscientist John Anderson, also at Sussex, to help as they photographed a cuttlefish (Sepia officinalis) swimming around in a tank. © Copyright Reed Business Information Ltd.

Keyword: Animal Communication
Link ID: 3823 - Posted: 06.24.2010

By JOHN O'NEIL For smokers trying to quit, a day can feel a lot longer than 24 hours, and a new study shows that in fact a smoker's sense of time is distorted by going without nicotine. The study, published in the journal Psychopharmacology Bulletin, found that smokers allowed access to tobacco and nonsmokers were equally accurate in estimating a 45-second interval, calculating it on average at 52 seconds. But smokers who had not had cigarettes in 24 hours were off by far more, making an average guess of 71 seconds, said the study's lead researcher, Dr. Laura Cousino Klein, an assistant professor of biobehavioral health at Penn State. Copyright 2003 The New York Times Company

Keyword: Drug Abuse
Link ID: 3822 - Posted: 05.20.2003

DALLAS – – Researchers from UT Southwestern Medical Center at Dallas and the Mayo Clinic have discovered a novel genetic mutation that leads to a debilitating muscle condition known as myasthenia. Myasthenia, a severe form of muscle weakness, usually results from an autoimmune attack against the nerve-muscle junction in which the nerve's communication to the muscle is broken down. In a study appearing this week in the online early edition of Proceedings of the National Academy of Sciences, researchers unveil a new cause discovered in a single patient: a genetic mutation leading to a shutdown in muscle responsiveness to the nerve's electrical impulses. "This was a surprise in that it's a totally different mechanism for a well-researched disease," said Dr. Stephen Cannon, chairman of neurology at UT Southwestern, who studied the consequences of the genetic mutation. "Until this study, every single case of myasthenia ever examined had been attributed to a reduction in what's called the safety factor of neurotransmission – or how reliably the nerve talks to the muscle."

Keyword: Movement Disorders; Muscles
Link ID: 3821 - Posted: 06.24.2010