By GINA KOLATA Three groups of scientists report today that they independently replicated a controversial finding: severely diabetic mice can recover on their own if researchers squelch an immune system attack that is causing the disease. E-mail Gina Kolata at kolata@nytimes.com It is a discovery that was first published in 2001 and raised the hopes of people with Type 1 diabetes, which usually occurs in puberty and afflicts an estimated half-million to a million Americans. If the findings applied to humans, they might mean reversing a disease that had seemed incurable. The findings also gave rise to questions about using embryonic stem cells as replacement cells for diabetics, a method that is the focus of intense interest. If it is possible, in mice, for the pancreas to cure itself, and if the same finding holds true in humans — which, so far, is entirely unknown — adding embryonic stem cells as the source of new pancreas cells might provide little added benefit, if any. In any event, scientists are not yet ready to treat diabetic patients with embryonic stem cells; they first have to prod the cells to turn into insulin-secreting pancreas cells. Meanwhile, efforts to cure diabetes by transplanting pancreas cells from cadavers have met with limited success. Copyright 2006 The New York Times Company

Keyword: Obesity; Hormones & Behavior
Link ID: 8710 - Posted: 06.24.2010

Associated Press The narcolepsy drug modafinil should not be approved as a treatment for attention-deficit hyperactivity disorder in children until more is learned about a possible link to a serious skin disease, federal advisers said yesterday. A Food and Drug Administration advisory committee voted 12 to 1 against recommending modafinil as safe for children with ADHD. Earlier, the psychopharmacologic drugs panel unanimously agreed that modafinil works as a treatment for ADHD. The FDA is not required to follow the recommendations of its advisory panels but usually does. The committee recommended that Cephalon Inc. undertake a 3,000-patient trial to determine the risk modafinil may pose for Stevens-Johnson syndrome. Drug reactions cause nearly all cases of the sometimes fatal skin disease, which can produce widespread blistering and rashes, according to the Merck Manual. © 2006 The Washington Post Company

Keyword: ADHD; Sleep
Link ID: 8709 - Posted: 06.24.2010

By John Bohannon Sick fathers aren't much fun. But a study of birds suggests that sometimes ill dads make better parents, especially when they fear they don't have much longer to live. According to one evolutionary theory, males from long-lived animal species are careful investors when it comes to reproduction. When deciding how much effort to put into taking care of themselves versus being a good father, they consider their future prospects. If the future looks good, with many years of potential mating ahead, then it pays to keep their own health top priority. But when animals reach their golden years, it makes more sense to disregard illness and invest more time and effort in caring for offspring. This strategy would boost the chances that the animal's genes are passed on to the next generation. But do animals really keep track of their future prospects so carefully? A team led by Roxana Torres, a biologist at the Mexican National Autonomous University in Mexico City, used the blue-footed booby as a test case. The birds usually live for about 15 years, and their chicks require a long investment--6 months of baby-sitting from both mother and father. The researchers captured 50 males from a booby colony 2 weeks before their mates were due to lay eggs. Then, to put the fathers between a rock and a hard place, the researchers injected the birds with a molecule from the cell wall of Escherichia coli bacteria. The molecule poses no threat to health, but it causes the immune system to go on red alert, bringing all the symptoms of a bacterial infection. As a control, they injected some birds with the buffering solution alone. © 2006 American Association for the Advancement of Science

Keyword: Sexual Behavior; Evolution
Link ID: 8708 - Posted: 06.24.2010

Susan Milius What Martin Nweeia noticed first when he encountered narwhals, he says, was the sound. In May 2000, as spring was just reaching Baffin Island in the Canadian Arctic, a famed local hunter took Nweeia out on the ice searching the open water for those tusk-bearing, high-Arctic whales. "I was sitting on a bucket out on the ice doing polar bear watch," he says. At that time of year, daylight lasts around the clock, and at 3 a.m., the gray sky had orange streaks. "The water was like glass, and a light mist was rolling in," he says. "Then, I heard the breathing." Nweeia soon traced the sound to the dark bodies of at least 10 narwhals that had risen to the surface out in the open water. Their heavy, low-frequency, methodical breaths carried through the night as if "they were breathing in my ear," Nweeia says. It took considerable discipline, he says, to break the spell of their arrival and wake the hunter to go after them. Many people have searched for narwhals, but Nweeia may be the only Connecticut dentist to have done so. He practices in that state and teaches at Harvard School of Dental Medicine in Boston. And what's there for a dentist not to love about an animal with a 3-meter-long tooth—and the only spiraling tooth ever reported? Copyright ©2006 Science Service.

Keyword: Pain & Touch; Laterality
Link ID: 8707 - Posted: 06.24.2010

Andy Coghlan Men’s testicles may provide an “ethical” source of embryonic stem cells (ESCs), suggest new experiments in mice. A team in Germany has successfully grown mouse ESC-like cells from spermatagonial stem cells which normally turn into sperm. The ESC-like cells can be grown into all tissues of the mouse body, suggesting that if the same could be done in men, it would provide patients with a source of tissue-matched cells for repairing any damaged organs or tissue. So far, all existing colonies of human ESCs have been derived from surplus human embryos, leftover from infertility treatments. Because a human embryo is sacrificed in the process, many religious groups oppose such research, especially in the US where President George W Bush has placed heavy restrictions on federal stem cell researchers. The discovery that cells which behave like ESCs can now be obtained from adult mice may now open up the possibility of a similar “ethical” source from grown men. “We’re in the process of doing this in humans, and we’re optimistic,” says Gerd Hasenfuss of the Georg-August University of Göttingen, Germany, and head of the team which pioneered the breakthrough. © Copyright Reed Business Information Ltd.

Keyword: Stem Cells; Regeneration
Link ID: 8706 - Posted: 06.24.2010

By JEREMY PEARCE Dr. James H. Schwartz, a neurobiologist at Columbia whose research helped explain the biochemical basis of learning and memory, died on March 13 at NewYork-Presbyterian/Columbia hospital in Manhattan. He was 73. The cause was complications of leukemia, his family said. Dr. Schwartz was interested in the notion that changes in the electrochemical switches within the brain cause shifts in the function of brain circuits, leading to different behaviors. He studied sea slugs as a model for brain function in more complex animals. Much of his work involved the origins, at the cellular and molecular level, of learning and animal behaviors. Dr. Schwartz and others observed that learning was associated with changes in the structure of chromatin, a basic material found within a cell, in some neurons. With Dr. Eric R. Kandel and Thomas M. Jessell, Dr. Schwartz edited an influential textbook, "Principles of Neural Science" (1979), for medical students and neuroscientists. It is now about to enter its fifth edition. The book became "a standard of basic neuroscience, with a focus on how the nervous system generates and controls behavior" and includes clinical descriptions of neurological and psychiatric disorders, said John Koester, acting director of Columbia's Center for Neurobiology and Behavior, which Dr. Schwartz helped found in 1974. Copyright 2006 The New York Times Company

Keyword: Learning & Memory
Link ID: 8705 - Posted: 03.24.2006

By Shankar Vedantam Antidepressants fail to cure the symptoms of major depression in half of all patients with the disease even if they receive the best possible care, according to a definitive government study released yesterday. Significant numbers of patients continue to experience symptoms such as sadness, low energy and hopelessness after intensive treatment, even as about an equal number report an end to such problems -- a result that quickly lent itself to interpretations that the glass was either half empty or half full. The $35 million taxpayer-funded study was the largest trial of its kind ever conducted. It provided what industry-sponsored trials have rarely captured: Rather than merely ask whether patients are getting better, the study asked what patients most care about -- whether depression can be made to disappear altogether. The study has been eagerly awaited by physicians, patients and the pharmaceutical industry. According to government statistics, depression afflicts 15 million Americans a year. About 189 million prescriptions for antidepressants were written last year, and the disease costs the nation $83 billion annually because of treatment costs, lost productivity, absenteeism and suicide. © 2006 The Washington Post Company

Keyword: Depression
Link ID: 8704 - Posted: 06.24.2010

by Nancy Etcoff Barbara Herbert of southern England never knew she had an identical twin until, while searching for her biological mother at age forty, she discovered a sister who had been adopted and raised by another British family. When the two met for the first time, twenty-five years ago at a London tube stop, Herbert instantly recognized her mirror image, a woman who not only looked like her (down to the color and style of the clothes she wore), but who also laughed the way she did. “It was a very strange sensation,” said twin Daphne Goodship. “We were strangers, but did not feel it.” Their separate lives had done nothing, it appeared, to erase the identity of their origins. The twins soon discovered they shared many preferences: the color lilac, coffee served black and cold, the actor Brad Pitt. They shared aversions, too, including the fear of falling down stairs and the sight of blood. They had been reading the same books and cooking from the same recipes. Fifty hours of psychological and medical tests and 15,000 questions later, a team of scientists at the Minnesota Center for Twin and Adoption Research told the sisters they both had heart murmurs, thyroid problems, and allergies. A slim one-point difference separated their IQs. What was most striking to everyone, though, was that the twins had similar personalities and similar levels of happiness. They were bubbly and high-spirited, easily amused, and imbued with a great sense of fun. They even made the same jokes. “Well, I won’t be wearing my ball dress tonight!” each one said as scientists put electrodes on their chests. Because they laughed the same way, researcher David Lykken called them “the giggle twins.” Could it be, scientists wondered, that happiness is a lucky accident of birth? © 2002 Science & Spirit Magazine.

Keyword: Genes & Behavior; Emotions
Link ID: 8703 - Posted: 06.24.2010

A single pain receptor is solely responsible for the kick delivered by mustard oil and garlic, according to research in the March 24 Cell. Mustard oil is the active ingredient in mustard and in the pungent green sushi condiment known as wasabi. The sensory receptor also underlies the response to a variety of environmental irritants, such as acrolein, the researchers report. Acrolein accounts for the toxic and inflammatory actions of tear gas, vehicle exhaust, tobacco smoke, and the byproducts of some chemotherapy drugs widely used in the treatment of cancer, severe arthritis, multiple sclerosis, and lupus. The insights therefore suggest potential new avenues for the development of anti-inflammatory and pain medications, according to the researchers. The research team, led by David Julius at the University of California San Francisco, report cellular and behavioral evidence in mice linking the sensory ion channel TRPA1 to the pain response evoked by mustard oil, garlic, and acrolein. Mice deficient for TRPA1 also show pronounced deficits in their reaction to a natural agent produced in response to injury, inflammation, or oxygen shortage, they found. "By understanding what triggers TRP channel receptors, we can learn something new about how pain is sensed," Julius said. The TRP family of channels includes receptors for a variety of natural plant products that elicit pain and inflammation by stimulating a subset of neurons, collectively known as nociceptors.

Keyword: Pain & Touch
Link ID: 8702 - Posted: 03.24.2006

Contrary to traditional wisdom, being a leftie promotes survival from attacks, at least in the world of snails and crabs, according to a report by researchers at Yale and Cornell in the Biology Letters of the Royal Society, UK. While rare in nature, many organisms including humans have some, but few, members that are lefties. Author Gregory P. Dietl, post-doctoral fellow in geology and geophysics at Yale has studied the survival advantages or disadvantages of being a "leftie" by working with snails and their predatory crabs. "One of the conclusions we draw from the interaction between crabs and these snails is that in the adversarial mode, lefties have a competitive advantage as long as they remain rare," said Dietl. This parallels some social interactions in human cultures, such as sporting competitions in which left-handed players enjoy an advantage over their right-handed opponents. The functional advantage of this rare reversal in shell-coiling direction, while a topic of fascination for scientists and laypersons alike, has evaded explanation. Persistence of handedness in snails is most often associated with a mating advantage. In this case, snails mate most effectively with snails whose shells coil in the same direction. The overwhelming majority of snail species are right-handed -- their shells coil clockwise. Dietl studied a species of snail that are lefties, and have shells that coil counterclockwise.

Keyword: Laterality; Aggression
Link ID: 8701 - Posted: 03.24.2006

Are you more like an active ape… or a motionless monkey? Biologists at Oregon Health and Science University's Oregon National Primate Research Center say the tendency to get a lot of exercise — or not — seems to be set before adulthood. "Some monkeys are very sedentary during the day and other monkeys are up to eight to 10-fold more active, day after day after day," says OHSU's Judy Cameron, a professor of behavioral neuroscience. As they reported at the annual meeting of the Society for Neuroscience, the researchers put motion-measuring devices on adult monkeys' collars to monitor their daily activity. "These are three-way accelerometers measuring movement in all three directions," she explains. "[They are] about the size of a wristwatch, so they can be very non-invasively put on a collar of an animal and the animal is very comfortable wearing them." This allowed the researchers to record the animals' activities twenty-four hours a day. Cameron and her colleagues decided to study monkeys because of their similarity to humans. It's difficult to translate activity studies done in more common lab animals, like mice, into meaningful information for people. "Rodents like to run for hours and hours at a time, and they may run thousands of rotations a night. It's hard to know what that's equivalent to in people — would it mean running a huge number of miles a day?" Cameron says. "So you want to use a species that would be more comparable to humans." As she explains, monkeys have similar patterns of natural movement to people, which include playing, sitting around, and socializing. © ScienCentral, 2000-2006.

Keyword: Obesity
Link ID: 8700 - Posted: 06.24.2010

By Laura Blackburn One of the chief instigators of multiple sclerosis (MS) has a split personality. Immune cells known as microglia usually protect the nervous system, but when things go wrong, they strip neurons of myelin--their protective coating--leading to muscle spasms and memory difficulties. Now researchers have uncovered new clues into what turns these cellular Dr. Jekylls into Mr. Hydes. When good microglia go bad, it's usually because of a protein called interferon gamma (IFN-gamma). Produced by the body's T-cells, IFN-gamma stimulates microglia to produce a myelin-damaging protein called tumor necrosis factor alpha (TNF-alpha). To see if microglia could be turned away from the dark side, neuroimmunologist Michal Schwartz of the Weizmann Institute of Science, in Rehovet, Israel, examined mouse and rat models of MS. When the researchers looked at the response of microglia in these animals to various levels of IFN-gamma and a related protein, interleukin-4 (IL-4), they found that only high levels of IFN-gamma trigger microglia's damaging rampages. When IFN-gamma is low, microglia protect neurons just fine. And when IL-4 is around, it overcomes the malicious effects of IFN-gamma and TNF-alpha, switching microglia from nasty to nurturing. Under these conditions, microglia encourage the cells that make myelin, called oligodendrocytes, to repair damaged neurons. © 2006 American Association for the Advancement of Science.

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 8699 - Posted: 06.24.2010

In today's "24/7" society, many people cut back on sleep to squeeze in more time for work, family obligations, and other activities. But skimping on sleep can be harmful. A comprehensive new handbook from the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH) explains that sleep is not merely “down time” when the brain shuts off and the body rests. “Our brains are very active during sleep, and research has shown that adequate sleep is important to our overall health, safety, and performance," notes Michael Twery, PhD, acting director of NHLBI's National Center on Sleep Disorders Research. "Scientists also have a better understanding of how a chronic lack of sleep or an untreated sleep disorder can impair health. Like good nutrition and physical activity, adequate sleep is critical for continued good health.” “Your Guide to Healthy Sleep” provides the latest science-based information about sleep in an easy-to-understand format. The 60-page handbook describes how and why we sleep, and offers tips for getting adequate sleep, such as sticking to a sleep schedule, relaxing before going to bed, and using daylight or bright light to help you adjust to jet lag and shift work schedules. Sleep disorders such as insomnia (trouble falling asleep or staying asleep, or unrefreshing sleep), sleep apnea (brief periods of pauses in breathing or shallow breathing while you are sleeping), restless legs syndrome (an almost irresistible urge to move the legs that can make it difficult to fall asleep or stay asleep), and narcolepsy (excessive and overwhelming daytime sleepiness despite adequate nighttime sleep) are also described with information on diagnosis and treatment. In addition, a sample sleep diary helps readers track their sleep-related habits.

Keyword: Sleep
Link ID: 8698 - Posted: 06.24.2010

Carina Dennis To sense where the various parts of our body are, we sometimes rely on signals that originate in our brain rather than in our fingers or toes, a new study shows. The so-called sixth sense, known as proprioception, is essential to many basic actions, including walking without having to look at your feet or touching your nose with your eyes closed. But scientists have long pondered how this sense works. It is generally accepted that sensors in the skin, muscles and joints send information to the brain that is crucial to sensing limb position. Now researchers in Australia have evidence of the importance of outgoing messages from the brain. "This will provoke debate, because the idea that the sense of position is mostly the result of the sensory receptors is well-entrenched," says Timothy Miles, a physiologist at the University of Adelaide, Australia, who is independent of the study. Janet Taylor from the University of New South Wales in Sydney and her colleagues strapped the forearm and hand of volunteers into a covered apparatus that prevents the subject from seeing the position of their hand. Under normal conditions, the subject could accurately tell if and how their hand had been moved by an experimenter or by themselves. ©2006 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 8697 - Posted: 06.24.2010

By Shankar Vedantam Antidepressants fail to cure the symptoms of major depression in half of all patients with the disease even if they receive the best possible care, according to a definitive government study released yesterday. Significant numbers of patients continue to experience symptoms such as sadness, low energy and hopelessness after intensive treatment, even as about an equal number report an end to such problems -- a result that quickly lent itself to interpretations that the glass was either half empty or half full. The $35 million taxpayer-funded study was the largest trial of its kind ever conducted. It provided what industry-sponsored trials have rarely captured: Rather than merely ask whether patients are getting better, the study asked what patients most care about -- whether depression can be made to disappear altogether. The study has been eagerly awaited by physicians, patients and the pharmaceutical industry. According to government statistics, depression afflicts 15 million Americans a year. About 189 million prescriptions for antidepressants were written last year, and the disease costs the nation $83 billion annually because of treatment costs, lost productivity, absenteeism and suicide. David Rubinow, a professor and the chairman of the psychiatry department at the University of North Carolina at Chapel Hill, said the results are an "illuminating and disconcerting" window into the affliction that is thought to fuel many of the 30,000 suicides committed each year in the United States. © 2006 The Washington Post Company

Keyword: Depression
Link ID: 8696 - Posted: 06.24.2010

By GARDINER HARRIS GAITHERSBURG, Md., — Stimulants like Ritalin lead a small number of children to suffer hallucinations that usually feature insects, snakes or worms, according to federal drug officials, and a panel of experts said on Wednesday that physicians and parents needed to be warned of the risk. The panel members said they hoped the warning would prevent physicians from prescribing a second drug to treat the hallucinations caused by the stimulants, which one expert estimated affect 2 to 5 of every 100 children taking them. Instead, they said, the right thing to do in such cases was to stop prescribing the stimulants. On Feb. 9, a different advisory committee voted 8 to 7 to recommend that the Food and Drug Administration place its most serious warning label, a so-called black box, on the labels of stimulants to warn that they could have dangerous effects on the heart, particularly in adults. That recommendation grew out of reports that 25 people, mostly children, had died suddenly while taking the drugs. The twin conclusions come more than 50 years after Ritalin was first approved to treat attention deficit disorder and hyperactivity. Since then, stimulants have become among the most widely prescribed medicines in the world. In the United States alone, about 2.5 million children and 1.5 million adults take them; as many as 10 percent of boys ages 10 to 12 do. Copyright 2006 The New York Times Company

Keyword: ADHD
Link ID: 8695 - Posted: 06.24.2010

Three decades after Richard Dawkins revolutionised our understanding of living things with The Selfish Gene, evidence has accumulated to back his cold-eyed vision of how bodies, families and society are shaped by the simple "duplicate me" message in our genetic instructions. His book, which has sold more than a million copies, did not mean to imply that genes have actual motives, only that their effects can be described as if they do: the genes that get passed on to the next generation are the ones whose consequences serve their own interests, not necessarily those of the societies or even the organisms in which they find themselves. We are merely vehicles to help replicate DNA, according to the Oxford University biologist. A Cambridge University team reported the consequences for meerkats, those loveable stars of natural history films, a day or two before Prof Dawkins marked the 30th birthday of his book last week, with a packed Darwin@LSE event with Ian McEwan, Dan Dennett, Matt Ridley, Sir John Krebs and Melvyn Bragg at the London School of Economics. A meerkat group is closely related and this is why they look out for each other. But the image of caring creatures standing on endless sentry duty to protect their pups and family does not quite tell the full story, according to an eight-year study carried out on the Kuruman River Reserve by Dr Andrew Young and Prof Tim Clutton-Brock. © Copyright of Telegraph Group Limited 2006.

Keyword: Evolution; Sexual Behavior
Link ID: 8694 - Posted: 06.24.2010

New research shows that one in three to four people who do not achieve a full remission of symptoms from an initial antidepressant became symptom-free after changing to or adding a second antidepressant. Phase two results of the four-phase study on treatments for depression – the largest of its kind – appear online in two companion articles in today's New England Journal of Medicine. "The message to the patient is: 'Hang in there. If the first treatment does not relieve your symptoms, consider changing or adding another medication. Follow instructions from your doctor, and don't give up,' " said Dr. A. John Rush, vice chairman of clinical sciences and professor of psychiatry at UT Southwestern. He is principal investigator of the study and lead author of one of the articles. "For a depressed individual, it may not matter so much what drug is being prescribed, but that the person moves forward and keeps trying." Designed to assess the effectiveness of various treatments for depression in "real-world" settings for people who also have other medical and psychiatric conditions, the $35 million, six-year study – designated STAR*D (Sequenced Treatment Alternatives to Relieve Depression) and funded by the National Institute of Mental Health (NIMH) – involved nearly 3,000 patients at 41 primary-care and psychiatric clinics. Researchers at 14 medical institutions worked together under the direction of UT Southwestern as the national coordinating center.

Keyword: Depression
Link ID: 8693 - Posted: 06.24.2010

Findings could help identify cause of schizophrenia, Parkinson's, drug addiction Amid reports that a drug used to treat Parkinson's disease has caused some patients to become addicted to gambling and sex, University of Pittsburgh researchers have published a study that sheds light on what may have gone wrong. In the current issue of Proceedings of the National Academy of Sciences, Pitt professor of neuroscience, psychiatry, and psychology Anthony Grace and Pitt neuroscience research associate Daniel Lodge suggest a new mechanism for how the brain's reward system works. The main actor in the reward system is a chemical called dopamine. When you smell, touch, hear, see, or taste a pleasurable stimulus, the dopamine neurons in your brain start firing in bursts. So-called "burst firing" is how the brain signals reward and modulates goal-directed behavior. But just how the stimulus you perceive causes neurons to switch into or out of this mode has been a mystery. Using anesthetized rats, Lodge and Grace found that one area in the brain stem, known as the laterodorsal tegmental nucleus, is critical to normal dopamine function. "We've found, for the first time, the brain area that acts as the gate, telling neurons either to go into this communication mode or to stop communicating," says Grace. "All the other parts of the brain that talk to the dopamine neurons can only do it when this area puts them into the communication mode."

Keyword: Drug Abuse
Link ID: 8692 - Posted: 03.23.2006

Sending tiny electric pulses to a part of the brain controlling motor function helps ischemic stroke survivors regain partial use of a weakened hand, new Oregon Health & Science University research shows. But coupling the technique known as cortical stimulation with aggressive rehabilitation is key to reversing the impairment, doctors say. "It's the coolest thing in stroke I've seen in a long time," said Helmi Lutsep, M.D., associate professor of neurology and associate director of the Oregon Stroke Center, OHSU School of Medicine. In a study examining the safety of cortical stimulation therapy, Lutsep and co-investigators found that stroke patients who received stimulation with rehabilitation improved "significantly" better in hand mobility and strength tests than people undergoing rehabilitation alone. "Everybody improved to some degree, because even in the subjects who received some rehabilitation, we did see improvement," Lutsep said. "What the data suggested is those who received the (stimulation) implant improved more." The study was published this month in the journal Neurosurgery. Lutsep's co-investigators were Jeffrey A. Brown, M.D., of Wayne State University, Detroit, Martin Weinand, M.D., of the University of Arizona, Tucson, and Steven C. Cramer, M.D., of the University of California, Irvine.

Keyword: Stroke
Link ID: 8691 - Posted: 03.23.2006