By JESSICA KOVLER At 27, Ken Baker still had the sexual development of a child. He was pudgy, stubble-free and could pass for a high school freshman. At age 15, his development was brought to a halt by a marble-size tumor on his pituitary gland that went undiagnosed for over a decade. According to a study released by the American Association of Clinical Endocrinologists, one in five people will develop a pituitary tumor. Only one-third of these will cause serious disorders. Copyright 2002 The New York Times Company

Keyword: Hormones & Behavior; Development of the Brain
Link ID: 1938 - Posted: 04.23.2002

By ERIC NAGOURNEY Testosterone, often referred to as the male hormone, appears to play a role in maintaining mental sharpness as men age, researchers have found. After giving 300 older men a series of tests intended to measure skills like concentration and memory, the researchers found that the higher their testosterone level, the better the men did. Writing in the current issue of The Journal of the American Geriatrics Society, the lead author, Dr. Kristine Yaffe of the University of San Francisco, said the study looked at how much testosterone was actually available for the brain's use. Copyright 2002 The New York Times Company

Keyword: Hormones & Behavior; Alzheimers
Link ID: 1937 - Posted: 04.23.2002

By HENRY FOUNTAIN The naked mole-rat is an odd beast. With its bare, pink skin and huge protruding incisors, this East African rodent is sometimes described as a hot dog with teeth. It spends most of its time in dark tunnels, so its vision is limited, but it can navigate both forward and backward with ease, aided by sensory hairs at either end. Socially, it is strange, too: with a single breeding queen supported by scores of workers, a mole-rat colony is the mammalian equivalent of a beehive. Now, it turns out, even its brain is weird. Copyright 2002 The New York Times Company

Keyword: Pain & Touch; Evolution
Link ID: 1936 - Posted: 04.23.2002

A bad temper can lead to a risk of premature heart attack, scientists claim. Their comments are based on findings that young men who quickly react to stress with anger are three times more likely to develop heart disease. Research shows these men were five times more likely than their calmer counterparts to have an early heart attack, even without a family history of the condition. Some expressed their anger, others were able to conceal it, while many became irritable or engaged in "gripe sessions". Dr Patricia Chang, who co-ordinated the US-based research, said: "In this study, hot tempers predicted disease long before other traditional risk factors like diabetes and hypertension became apparent. (C) BBC

Keyword: Emotions; Stress
Link ID: 1935 - Posted: 04.22.2002

By Larry O'Hanlon, Discovery News — The best singers not only get all the chicks, but better health as well — at least among starlings. A new study has revealed that the better male starling crooners — preferred by females as mates — tend to have extra vigorous immune systems to fight off diseases. That's a trait any mother would want their offspring to have, said behavior researcher ornithologist Deborah Duffy, who just finished her doctoral work at Johns Hopkins University. Her paper on the matter appears in the April 22 issue of The Proceedings of the Royal Society of London. Copyright © 2002 Discovery Communications Inc.

Keyword: Sexual Behavior
Link ID: 1934 - Posted: 06.24.2010

Lithium has been effective in the treatment of bipolar or manic depressive disease for more than 40 years yet scientists still don't understand fully how it works, that is, what target in the cell the lithium hit once it began circulating in the blood. Without this information, it is difficult to know how to create other, perhaps more effective drugs, or drugs that will work for patients who do not respond to lithium. A scientist who provided important insights into possible targets of lithium - and this year's recipient of the American Society for Biochemistry and Molecular Biology's Schering Plough Award -- will describe his current research on April 21 at the Experimental Biology 2002 meeting in New Orleans. Dr. John D. York, Howard Hughes Medical Institute Assistant Investigator, Duke University Medical Center, focuses on the elucidation of communication pathways between cells - a process called signaling - and the mechanisms by which defects in these pathways may lead to diseases such as manic depression and cancer. Dr. York is perhaps best known for identifying biological roles for "orphan" intracellular signaling molecules known in general as inositol polyphosphates, a discovery which changed how scientists regard inositol signaling and its possible impact on disease and the design of new therapies.

Keyword: Depression; Genes & Behavior
Link ID: 1933 - Posted: 04.22.2002

Discovery that clocks in organs use different genes could impact postgenomic research and circadian medicine BOSTON, MA –The daily rhythms of the body—once thought to be strictly governed by a master clock lodged in the brain—appear to be driven to a remarkable degree by tiny timepieces pocketed in organs all over the body. What‘s more, these peripheral timepieces appear to be strikingly idiosyncratic in appearance—more like Swatch watches than classic Timexes. Clocks located in the liver and heart appear to use very different sets of genes to perform essentially the same functions, researchers at Harvard Medical School and the Harvard School of Public Health report in the April 21 Nature online. The study, among the first to explore circadian time mechanisms outside the brain, could have a potentially broad impact on the burgeoning fields of circadian medicine and postgenomic science. Clinicians have known for years that organs function at different rates—the heart beats, kidneys transport ions and electrolytes, the liver metabolizes lipids, sugars, and amino acids differently over the course of the day—and have used this knowledge to design more effective drug regimens for patients. A better understanding of what drives those local rhythms, and how they go wrong, could aid physicians’ efforts.

Keyword: Biological Rhythms
Link ID: 1932 - Posted: 06.24.2010

It may not strike twice but lightning can have long-term effects People who are struck by lightning could go on to develop rare disorders of the nervous system, say scientists. Research suggests some lightning-strike victims show signs of involuntary movement disorders (IMDs), such as uncontrollable blinking, tic-like movements resembling Tourette's syndrome, hand tremors and muscle spasms. These type of complications are normally found in people who have experienced other types of electric shocks, which damage the brain and the central nervous system. However researchers from the Lightning Data Center of St Anthony Hospital in Denver, USA, say they found four lightning-strike patients who developed similar symptoms. (C) BBC

Keyword: Brain Injury/Concussion; Tourettes
Link ID: 1931 - Posted: 04.22.2002

by Francesco Fiondella, BioMedNet News When nerves are severed by spinal cord injury, a tangle of long and branched molecules forms around them like "overgrown shrubbery," as one expert puts it, and prevents the damaged fibers from regenerating. Researchers now say that selectively pruning this molecular growth with chemicals results in "modest but significant" nerve regeneration in rat models, according to published and unpublished findings presented this week. A class of molecules known as chondroitin sulphate proteoglycans (CSPGs), a protein called Nogo, and another called myelin associated glycoprotein (MAG) are among the most studied of this molecular shrubbery shown to inhibit nerve regeneration. © Elsevier Science Limited 2002

Keyword: Regeneration; Brain Injury/Concussion
Link ID: 1930 - Posted: 06.24.2010

Lipitor ™ (atorvastatin), the most frequently used cholesterol lowering agent in the world, also has the ability to influence the immune system and proved effective in reversing paralysis in a mouse model of multiple sclerosis. Dr. Sawsan Youssef, a postdoctoral fellow in the laboratory of Dr. Lawrence Steinman, Stanford University, reported the study on April 23 at the Experimental Biology 2002 meeting in New Orleans. Multiple sclerosis is caused by the immune system attacking the body’s own central nervous system, breaking down the myelin that sheathes and protects CNS nerves, impairing the body’s ability to move normally, and eventually causing paralysis. The T lymphocytes of the mice with which the research team worked are sensitized to brain antigens so that they produce an over-abundance of cytokines, pro-inflammatory chemicals that inflame the CNS, causing demylination of nerve sheaths through the same mechanism and in the same manner as happens in human multiple sclerosis. As in humans with MS, this mouse condition (called experimental autoimmune encephalomyelitis or EAE) can occur in either an acute or relapsing form. The researchers found that oral treatment with lipitor could prevent both the acute and relapsing form of the multiple sclerosis-like disease in the mice, and could also reverse symptoms in mice with the ongoing chronic relapsing form of the disease.

Keyword: Multiple Sclerosis
Link ID: 1929 - Posted: 06.24.2010

Investigators at Howard University have recently observed the antidepressant effect of nicotine in Wistar-Kyoto (WKY) rats, a putative behavioral model of depression. Drs. Youssef Tizabi and K. Y. Tyler will present their findings at the Experimental Biology 2002 meeting in New Orleans on April 22. When compared to the general population, individuals with a history of clinical depression are more likely to smoke cigarettes. In addition, depressed patients often encounter difficulty in their smoking cessation efforts, which may partially be attributed to relapsed depressive episodes during withdrawal. Although cigarette smoke contains over 3,000 chemicals, nicotine is the primary constituent that acts on the brain. As a result, scientists have suggested that cigarette smoking may be an attempt by depressed individuals to self-medicate with nicotine. Depression is a major mental health disorder that is estimated to affect nearly 10 million American adults each year. Treatment of depressive illness, which includes various antidepressant medications and psychotherapy, is effective in 60-80 percent of patients. Despite the relative success of current antidepressant therapies, the precise cause of depression remains unclear. Animal models of depression, such as the WKY rat, are important research tools that can be used to screen potential antidepressant drugs and to study the underlying brain mechanisms involved in depression.

Keyword: Depression; Drug Abuse
Link ID: 1928 - Posted: 04.21.2002

Exposure to light can throw off your internal clock By Colette Bouchez HealthScoutNews Reporter THURSDAY, (HealthScoutNews) -- If a barking dog or noisy neighbors wake you up in the middle of the night, be sure to vent your anger in the darkness. New research shows that even short periods of light exposure in the middle of the night -- say more than an hour -- are enough to disrupt your circadian rhythm. That's important because your circadian rhythm is the natural biological clock that influences a wide number of physiological functions, as well as basic drives like sleep, hunger and sex. Copyright © 2002 ScoutNews, LLC. All rights reserved.

Keyword: Sleep; Biological Rhythms
Link ID: 1927 - Posted: 06.24.2010

In the old days, preschoolers had no more pressing business than to learn how to play. New research shows that they benefit from instruction in words and sounds By Barbara Kantrowitz and Pat Wingert NEWSWEEK When you walk through the brightly colored door of the Roseville Cooperative Preschool in northern California, you’re entering a magical, pint-size world where 3- and 4-year-olds are masters of the universe. At the science table, they use magnifying glasses to explore piles of flowers, cacti and shells. In the smock-optional art area, budding da Vincis often smear blotches of red, blue and yellow directly on the table. (It’s wiped off with a damp cloth when the next artist steps up.) There are ropes for climbing and two loft areas: one carpeted and filled with books and a dollhouse, and the other with a clear Plexiglas floor, perfect for keeping an eye on the activities below. There are no letters or numbers on the walls to distract from this focused play. The only rule, says director and founder Bev Bos, is that the kids are in control. “I tell other teachers, ‘Forget about kindergarten, first grade, second grade’,” she says. “We should be focusing on where children are right now.” SOUNDS LIKE AN IDYLLIC preschool learning environment, right? Wrong, according to a growing number of early-education researchers. Until quite recently, Bev Bos’s philosophy was the standard at preschools around the country, and there are still lots of teachers who passionately defend the idea that they should be helping kids feel secure and learn to play well with others, not learn the three Rs. But researchers now say the old approach ignores mounting evidence that many preschoolers need explicit instruction in the basics of literacy—the stuff most of us started to learn in first grade, how words fall on a page and the specific sounds and letters that make up words. New brain research shows that reading is part of a complex continuum that begins with baby talk and scribbles, and culminates in a child with a rich vocabulary and knowledge of the world. While some children acquire the literacy skills they need by osmosis, through their everyday experiences, many don’t. Most at risk are children of poverty, who are twice as likely to have serious trouble reading. But studies have also shown that at least 20 percent of middle-class children have reading disabilities and that early intervention could save many of them from a lifetime of playing catch-up. • MSNBC Terms, Conditions and Privacy © 2002

Keyword: Language; Dyslexia
Link ID: 1926 - Posted: 06.24.2010

A study by scientists in the US has given every teenager the perfect excuse to sleep late at weekends. Research carried out at Northwestern University in Illinois has found that teenagers need extra sleep at the weekend to catch up on hours lost during the week. They also suggest that failing to have long lie-ins could lead to behavioural problems and poor academic results. The results, presented at the American Academy of Neurology's annual meeting in Denver on Friday, show that young people sleep on average 8.5 hours on weekdays and more than 9.5 on weekends (C) BBC

Keyword: Sleep; Development of the Brain
Link ID: 1924 - Posted: 04.20.2002

Ben Harder In 1988, physician and amateur moth enthusiast Kenneth D. Frank published a scientific paper that pulled together much of what researchers then knew about the consequences of artificial night-time lighting on moths. That paper is the closest thing the nascent field of artificial-light ecology has to a classic work. It didn't exactly trigger the response one might expect from a seminal study, however. The report has received precious little attention and stimulated no immediate cascade of follow-up research. Frank recently searched the scientific literature to count how many subsequent papers had made reference to his study—and found exactly one. Nevertheless, Frank and a handful of other scientists are endeavoring to synthesize a coherent understanding of the ecological impacts of artificial light on a multitude of organisms. These efforts are gradually gaining momentum. From anecdotal reports of little-studied phenomena—such as moths' tendency to perish, Icarus-style, in lamps and flames—researchers suspect that artificial night lighting disrupts the physiology and behavior of nocturnal animals. In many cases, scientists have few reliable data on which to rest conclusions—but every reason to be concerned. From Science News, Vol. 161, No. 16, April 20, 2002, p. 248. Copyright ©2002 Science Service. All rights reserved.

Keyword: Biological Rhythms
Link ID: 1923 - Posted: 06.24.2010

John Pickrell As dawn breaks on a misty Welsh morning, the earliest birds to break into song are likely to include European robins, followed by blackbirds and song thrushes and then a plethora of other species as sunlight crowns the horizon. The last to join the chorus, such as chaffinches and blue tits, may not chime in until 100 minutes after the first crooners began. This pattern is repeated worldwide, and ornithologists have often pondered what determines when a particular species begins its morning singing. Now, scientists say that they've found the explanation: The larger a bird's eyes, the earlier it starts to sing. The staggering of avian choruses was first documented 70 years ago but has remained unexplained. Now, researchers have revisited an idea first proposed in the 1960s but never tested. It's that visual acuity—determined by eye size—governs when birds start to sing. From Science News, Vol. 161, No. 16, April 20, 2002, p. 245. Copyright ©2002 Science Service. All rights reserved.

Keyword: Biological Rhythms; Sexual Behavior
Link ID: 1922 - Posted: 06.24.2010

Ben Harder At common environmental concentrations, the popular weed killer atrazine strips male frogs of a key hormone and turns some of them into hermaphrodites, according to new research. The finding raises concerns that the chemical may be contributing to global amphibian declines. In use for about 4 decades and currently employed in 80 countries atrazine is the most common herbicide in the United States. It's found in virtually all the nation's waterways and is especially prevalent around cornfields in the Midwest. It has also been identified in tests of preschoolers' drinking water (SN: 11/3/01, p. 285: Available to subscribers at http://www.sciencenews.org/20011103/note16.asp). "There seems to be no atrazine-free environment," says Tyrone B. Hayes of the University of California, Berkeley. Past research has found no evidence that typical environmental concentrations of atrazine cause premature death or abnormal growth in amphibians. The new research, which Hayes and his colleagues report in the April 16 Proceedings of the National Academy of Sciences, similarly finds that mortality and overall growth of the common lab frog Xenopus laevis are unaffected by atrazine. From Science News, Vol. 161, No. 16, April 20, 2002, p. 243. Copyright ©2002 Science Service. All rights reserved.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 1921 - Posted: 06.24.2010

By C. CLAIBORNE RAY Q. Why do chickens have white meat and dark meat and ducks have only dark meat? A. Chickens and ducks have different exercise habits and different muscle structures, with differing levels of a dark substance called myoglobin. Chickens, which are mostly earthbound, with an occasional spurt of flying, have breasts that contain mostly fast-twitch muscle fibers; these contract powerfully for a short hop in the air, but they soon become tired. Copyright 2002 The New York Times Company

Keyword: Muscles
Link ID: 1920 - Posted: 04.20.2002

Whether for finding food, avoiding predators or choosing a mate, the sense of smell is critical for the existence of many creatures. We humans, able to distinguish over 10,000 scents, utilize our sense of smell for a multitude of activities from enjoying the aroma of freshly brewed coffee to deciding whom not to sit next to on the bus. Scientists are now beginning to understand how the nose and brain process the complex information that gives rise to the perception of smell. Copyright © 1995-2002 UniSci. All rights reserved.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 1918 - Posted: 06.24.2010

BOSTON – The identification of a protein that enables the body to overcome resistance to the hormone leptin could help scientists move one step closer to creating a drug therapy to help prevent and treat obesity. The findings, made by researchers at Beth Israel Deaconess Medical Center (BIDMC), are reported in the April 16 issue of Developmental Cell. Nearly all obese individuals are resistant to leptin, the hormone that signals the brain that our appetites are satisfied and we can stop eating. For this reason, explains study co-senior author Barbara Kahn, M.D., Chief of Endocrinology and Metabolism at BIDMC, efforts made several years ago to use leptin in drug form to treat obesity were largely unsuccessful. “The majority of obese people actually have high levels of leptin,” explains Kahn, who is a Professor of Medicine at Harvard Medical School. “But they are unable to put it to use.” In this new research, Kahn, together with co-senior author Benjamin Neel, M.D., Ph.D., – Director of the Cancer Biology Program at BIDMC who studies the biological functions of molecules known as protein-tyrosine phosphatases – initially began studying PTP1B (protein tyrosine phosphatase 1B) to determine its role in regulating insulin receptor signaling.

Keyword: Obesity
Link ID: 1917 - Posted: 06.24.2010