Lauran Neergaard, Associated Press — Scientists have discovered molecular janitors that clear away a sticky gunk blamed for Alzheimer's disease — until they get old and quit sweeping up. The finding helps explain why Alzheimer's is a disease of aging. More importantly, it suggests a new weapon: drugs that give nature's cleanup crews a boost. "It's a whole new way of thinking in the Alzheimer's field," said Dr. Andrew Dillin, a biologist at California's Salk Institute for Biological Studies who led the new research. The discovery, published Thursday by the journal Science, was made in a tiny roundworm called C. elegans. What do worms have to do with people? They're commonly used in age-related genetics research, and the new work involves a collection of genes that people harbor, too. Dillin's team from Salk and the neighboring Scripps Research Institute already is on the trail of potential drug candidates. About 4.5 million Americans have Alzheimer's, a toll expected to more than triple by 2050 as the population grays. The creeping brain disease gradually robs sufferers of their memories and ability to care for themselves, eventually killing them. There is no known cure; today's drugs only temporarily alleviate symptoms. Copyright © 2006 Discovery Communications Inc.

Keyword: Alzheimers
Link ID: 9231 - Posted: 06.24.2010

By NATASHA SINGER Tests that indicated high testosterone levels for Floyd Landis during the Tour de France have again raised questions about whether such substances provide an unfair advantage. But does taking testosterone — a controlled substance whose possession is illegal unless prescribed for medical reasons — automatically improve athletic performance? In sports, testosterone shots or creams are supposed to be magic bullets that spur athletes to train harder, run or bicycle more quickly, jump higher, swim faster, hit a baseball farther, recover sooner, and, let’s not forget, increased sex drive and combativeness. Certainly, the idea that taking doses of the hormone gives competitors an unfair advantage is behind the brouhaha over Floyd Landis, the 2006 Tour de France winner who French officials say tested positive for elevated testosterone on the day of his remarkable comeback during Stage 17. Mr. Landis has denied taking any performance-enhancing substances. But some leading experts who study testosterone are not convinced that supplementing the hormone improves endurance or overall athletic performance. Unlike a hyper-caffeinated sports drink, the synthetic hormone does not provide an instant jolt, but works over time to bulk and fortify muscles. What other effects taking testosterone may have on athletes is the subject of heated debate. Copyright 2006 The New York Times Company

Keyword: Hormones & Behavior; Aggression
Link ID: 9230 - Posted: 06.24.2010

Kerri Smith It might not seem inevitable that overweight mothers will have fatter babies. But this is exactly what's happening in the United States, say researchers who have documented how the 'obesity epidemic' is being passed on to the next generation. The team, based at Harvard Medical School in Boston, Massachusetts, has found that the proportion of overweight babies has risen by almost two-thirds over the past two decades, so that 10% of babies now fall into this category. And the proportion of babies at the upper end of the weight scale — termed 'at risk of becoming overweight' — has risen by a third to 14%. The group, led by Matt Gillman, followed more than 120,000 children between birth and 6 years of age, monitoring their weight and height. Infants from birth to 6 months old showed a particularly large increase in obesity from the 1980s to the 2000s, they add. A mother who gains a lot of weight during pregnancy can predispose her child to being overweight for life, says Gillman, who reports the work in the journal Obesity1. In extreme cases, putting on excessive weight when pregnant can lead to a condition called gestational diabetes in the mother. Studies of the disorder in rats show that it increases levels of the hormone insulin in pups. High insulin levels then boost appetite by acting on the hypothalamus, a part of the brain responsible for regulating food intake, he says. It seems the same thing can happen with people too. ©2006 Nature Publishing Group

Keyword: Obesity
Link ID: 9229 - Posted: 06.24.2010

Pictures of brain waves that reveal our ability to see colour could provide a new objective way to diagnose and monitor diseases that affect human colour perception. The research finding by a Universiy of New South Wales PhD student, Ms Mei Ying Boon, has earned her a nomination in this year's Fresh Science Awards. "Eye diseases such as glaucoma can alter people's ability to accurately see colour," says Ms Boon. "Therefore, studying brain activity could be a useful way to diagnose and monitor diseases and conditions that affect colour vision pathways in the brain." Ms Boon and her UNSW colleagues measured the brain waves of 22 adult volunteers while the volunteers viewed computer patterns composed of two different shades. The two colours ranged from very different (red and green) to very similar. If the viewer couldn't distinguish the colours, then the pattern was invisible to them. When the volunteers could see the pattern, their brain waves included a distinctively patterned wave. The researchers measured this signal three different ways and found it could be used to reveal the finest colour discriminations that individuals can make. The result: a potential visual health test.

Keyword: Vision
Link ID: 9228 - Posted: 08.10.2006

Doctors have completed the first step of a unique medical research study, evaluating 1,001 individuals at risk of developing Huntington's disease who do not know – nor do they want to know – whether they carry the genetic defect that causes the condition. An international team led by neurologist Ira Shoulson, M.D., of the University of Rochester Medical Center is trying to identify the earliest signs of the onset of the disease. The information will help clinicians design better studies of new drugs aimed at alleviating or postponing illness. It also helps researchers understand how patients evaluate potentially life-changing knowledge now available to patients through means such as genetic testing. Shoulson and colleagues from the Huntington Study Group reported their progress on the study known as PHAROS, or Prospective Huntington At Risk Observational Study, in the July issue of the Archives of Neurology. While the gene that causes the disease is known and can be identified through a blood test, fewer than one in 10 adults at risk for developing the disease have chosen to be tested. People at risk but who have not taken the test have a 50/50 chance of developing the disease. This at-risk group offers physicians a unique opportunity to witness the earliest signs of the disease, before anyone knows whether a person actually has the gene for Huntington's or not.

Keyword: Huntingtons
Link ID: 9227 - Posted: 06.24.2010

A dose of music can be a prescription for pain relief. As this ScienCentral News video explains, a new systematic study of music for pain finds that while music won't replace painkillers, it can boost their effectiveness. Marion Good loves to play music in her spare time. But as a professor of nursing at Case Western Reserve University's Frances Payne Bolton School of Nursing, she also prescribes it for pain relief. Her interest in researching music for pain began when as a nurse on a neurology unit she worked with patients suffering from back pain. "I would bring music into the room -- soft quiet music. Their faces just relaxed ... pretty soon they fell asleep," she says. "I had to tiptoe out of the room and come back an hour or two later to pick up my tape recorder." Good has been testing music with post-operative patients for more than 15 years. "I found that music does reduce pain up to about 31 percent in my studies in addition to medication," she says. Now the conclusion of a systematic analysis combining 51 clinical studies is music to her ears. The Cochrane Review of Evidence-Based Healthcare found that patients exposed to music rate their pain as less intense and even use lower doses of painkillers. © ScienCentral, 2000-2006.

Keyword: Pain & Touch
Link ID: 9226 - Posted: 06.24.2010

A brain protein that sustains nerve cells also regulates anxiety and alcohol consumption in rats, researchers from the University of Illinois at Chicago report in a study in the Aug. 9 issue of the Journal of Neuroscience. In previous studies, the UIC researchers had first identified a gene that controls anxiety and alcohol consumption. "We knew that gene, called CREB, controls the expression of a number of important genes in the brain," said Dr. Subhash Pandey, professor of psychiatry and anatomy and cell biology at UIC and Jesse Brown VA medical center and lead author of the paper. In the new study, they showed that a protein made by one of those CREB-controlled genes affects anxiety and drinking behavior depending on its level in two areas of the brain. Pandey and his colleagues injected DNA of complementary sequence to the gene of the protein, called brain-derived neurotrophic factor (BDNF), into the brains of rats to block the gene from expressing BDNF. The "anti-sense" DNA was injected into three areas of the amygdala, an area of the brain associated with emotion and fear. The researchers found that when levels of BDNF in the central and medial areas of the amygdala were lowered, anxiety and alcohol consumption increased. Decreased levels of BDNF in the third area, called the basolateral amygdala, had no effect.

Keyword: Emotions; Trophic Factors
Link ID: 9225 - Posted: 08.09.2006

Richard Van Noorden Are meerkats friendly altruistic animals who look after each other's young, or a back-stabbing selfish bunch? Research shows that although meerkat societies are generally cooperative, when it comes to pregnant females all bets are off. If a meerkat gets pregnant, she will actively try to kill the pups of other females. And now it seems that the most dominant female in the group has an extra strategy for ensuring her pups' survival: she chases and persecutes her potential baby-making competitors until they become so stressed that their fertility collapses1. Meerkats are often held up as examples of a cooperative society. The larger dominant female in a meerkat group usually succeeds in getting pregnant and has most of the babies. When this happens, the other subordinate workers pitch in with the babysitting and pup-feeding. The system is rather like that of the queen bee and worker bees in a hive. Such a hierarchy isn't unusual: other species practicing similar cooperative living include marmoset monkeys, naked mole-rats and acorn woodpeckers. A group of meerkats will run sentry duty for each other, and recent research suggests that they teach the young how to handle dangerous food2. ©2006 Nature Publishing Group

Keyword: Aggression; Sexual Behavior
Link ID: 9224 - Posted: 06.24.2010

By Michael Day People with Parkinson's disease are three times more likely than non-sufferers to have been troubled by allergic rhinitis – an inflammatory nasal response to pollen or other airborne particles – a new study finds. The results suggest that allergic diseases, such as hay fever, may be linked to brain inflammation that hastens the onset of the neuro-degenerative disorder, say researchers at the Mayo Clinic in Rochester, Minnesota, US. Previous studies have shown that non-steroidal anti-inflammatory drugs, such as ibuprofen, offered some protection against Parkinson's disease. These results prompted clinical neurologist James Bower and colleagues to investigate the links between inflammatory conditions and Parkinson’s disease. They studied 196 people with Parkinson’s disease and 196 others matched for age and gender. A comparison of the two groups revealed that those with Parkinson’s were 2.9 times more likely to have suffered rhinitis earlier in their lives. "People with allergic rhinitis mount an immune response with their allergies, so they may be more likely to mount an immune response in the brain as well, which would produce inflammation," Bower says. © Copyright Reed Business Information Ltd

Keyword: Parkinsons; Neuroimmunology
Link ID: 9223 - Posted: 06.24.2010

By PAUL BURNHAM FINNEY With the global economy now taking more executives to far-flung places like Beijing and Mumbai, jet lag is becoming a bigger aggravation, leading sleep researchers to work harder than ever to find suitable remedies. Trips to the other side of the globe make adjusting a traveler’s body clock — or circadian system — an even more drawn-out process. Jet-lag experts say they believe it takes one day for each time zone away from home, up to a maximum of six or seven days, to get fully in sync with local time. On brief visits to China, as Dr. Abinash Virk of the Mayo Clinic pointed out, business travelers often have no recourse except to plunge into meetings without time to recuperate. About eight million corporate travelers made overseas trips last year, according to the United States Office of Travel and Tourism Industries. Most were flying to Europe or the Pacific Rim, throwing their body clocks off kilter — and the effects are considered greater going East than West. There is no easy remedy. One problem in developing solutions is all the variation in travelers’ ability to handle jet lag. Sleep researchers have found that people who have dealt with sleep deprivation over long periods — on night shifts, for example — can tolerate jet lag better than most. Copyright 2006 The New York Times Company

Keyword: Sleep
Link ID: 9222 - Posted: 06.24.2010

By BENEDICT CAREY In one, government researchers found that an injection of a powerful anesthetic drug dissolved feelings of despair in a small group of severely depressed patients in a matter of hours, and that the effect lasted for up to a week in some participants. Doctors cautioned that the study was very small, and that the drug, ketamine, is a tightly controlled substance sometimes used as a club drug that can cause hallucinations, confusion and dangerous reactions, especially when ingested in unknown doses. In the other, psychiatrists in New York found evidence that antidepressant drugs significantly increased the risk that some children and adolescents would attempt or commit suicide. Doctors have debated this risk for years, but the authors of the study were skeptical of it, and their report may sway others. Both studies are being published in The Archives of General Psychiatry. In the first study, Dr. Carlos A. Zarate of the National Institute of Mental Health led a team of researchers who treated 18 chronically depressed men and women with the anesthetic ketamine. Five participants recovered from depression in the first day and were still significantly improved a week later. Most patients also received a placebo treatment during the study, an injection of saline solution, and showed no improvement. Copyright 2006 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 9221 - Posted: 08.08.2006

-- Using advanced brain sensor technology developed at the University of Oregon, researchers have confirmed often-debated findings from 1992 that showed infants as young as six months know when an arithmetic solution is wrong. Andrea Berger and Gabriel Tzur, both at Ben-Gurion University of the Negev in Israel, conducted new tests with 24 infants (14 males and 10 females) between six and nine months of age. The infants were shown one or two dolls in a videotaped puppet theater. Their view was then blocked briefly and the number of dolls was left unchanged, or one was added or removed. As in the earlier research, the infants looked longer when the screen was removed and the number of dolls differed from the previous exposure. In this new case, however, the infants wore special brain-monitoring netting manufactured by Electrical Geodesic Inc., a University of Oregon spin-off company. The 128-electrode netting allowed for much more extensive brain-wave monitoring than was available previously. The data was analyzed at the University of Oregon. The mean time for infants who saw the same number of dolls before and after was 6.94 seconds. They held their gaze longer (8.04 seconds) when the number of dolls differed. The time of measurement ended when a child looked away from the display. The findings were published this week online ahead of publication in the Proceedings of the National Academy of Sciences. They provide clarity to the scientific debate that surfaced soon after Karen Wynn, a Yale University psychologist, first published her results in Nature (Dec. 31, 1992), said Michael I. Posner, a professor of psychology at the University of Oregon.

Keyword: Development of the Brain
Link ID: 9220 - Posted: 08.08.2006

By JANE E. BRODY Everything you thought you knew about migraine headaches — except that they are among the worst nonfatal afflictions of humankind — may be wrong. At least that’s what headache researchers now maintain. From long-maligned dietary triggers to the underlying cause of the headaches themselves, longstanding beliefs have been brought into question by recent studies. Migraine and Risk of Cardiovascular Disease in Women (JAMA) As if that were not enough dogma to overturn, there is growing evidence that almost all so-called sinus headaches are really migraines. No wonder then that the plethora of sinus remedies on the market and the endless prescriptions for antibiotics have yielded so little relief for the millions of supposed sinus sufferers. While these findings may not be an obvious cause for joy among the afflicted, the good news is that there are available many drugs that can either prevent migraine attacks in the frequently afflicted or abort the headaches once they start. Migraine therapy has come a long way in two decades, and those who know or suspect that they have migraines would be wise to see a neurologist or a headache specialist to obtain a proper diagnosis and the best treatment now available. Copyright 2006 The New York Times Company

Keyword: Pain & Touch
Link ID: 9219 - Posted: 06.24.2010

New research suggests that nicotine treatment protects against the same type of brain damage that occurs in Parkinson’s disease. The research was conducted in laboratory animals treated with MPTP, an agent that produces a gradual loss of brain function characteristic of Parkinson’s. Experimental animals receiving chronic administration of nicotine over a period of six months had 25 percent less damage from the MPTP treatment than those not receiving nicotine. This protective effect may explain the lower incidence of Parkinson’s disease among smokers. The results also suggest that nicotine may be useful as a potential therapy in the treatment of early-stage Parkinson’s patients. The five-year study was conducted by researchers at The Parkinson’s Institute, an independent, non-profit research institute located in Sunnyvale, California. The study results are published in an on-line early release in the Journal of Neurochemistry (doi:10.1111/j.1471-4159.2006.04078.x) Parkinson’s disease is a progressive, neurodegenerative disease caused by the death of small clusters of cells in the midbrain. The gradual loss of these cells results in reduction of a critical transmitter called dopamine, the chemical messenger responsible for normal movement. “While we would never recommend that people smoke, these results suggest that nicotine promotes the survival of dopamine-producing cells in animals with no overt Parkinson’s symptoms,” said David A. Schwartz, M.D., director of the National Institute of Environmental Health Sciences, the federal agency that provided funding for the study.

Keyword: Parkinsons
Link ID: 9218 - Posted: 06.24.2010

Walking upright separates humans from most other creatures. Our bipedal gait is a wonder of balance but it remains unclear exactly how our brains manage to maintain this posture and use it to arrive at desired destinations. Now researchers have shown that the balance mechanisms of our inner ears play a decisive role in directing the human walk, as well as demonstrating that blindfolded volunteers can be steered by simple electrical current. Richard Fitzpatrick of the University of New South Wales in Australia and his colleagues gathered five men and five women and set them on a path. After staring at a target six meters (20 feet) away, the subjects were blindfolded and the researchers began running a slight electrical current through electrodes placed behind their ears. The current disrupted the constant electrical signaling produced by the sensory hair cells in the three canals of the inner ear. (They fire 90 times a second when the head is at rest.) Their continuous firing rate tells the brain exactly how the head is moving, which the brain then uses to maintain balance and direction. But when that signaling is disrupted, either by increasing or decreasing its rate, walking chaos ensues. The researchers could drive the subject to either the right or left depending on the direction of the current, basically convincing the brain that the head was rotating in a given direction and forcing it to make concomitant adjustments in the direction of the walk in order to arrive at the now misperceived goal. Further, if the researchers asked the subjects to tilt their heads forward toward the ground or backward toward the sky they would veer off course by an even greater degree. And when subjects held their heads only slightly back, the current completely disrupted their balance, inducing swaying and stumbling. © 1996-2006 Scientific American, Inc.

Keyword: Miscellaneous
Link ID: 9217 - Posted: 06.24.2010

Results of a new imaging study, supported in part by the National Institute on Drug Abuse (NIDA), National Institutes of Health, show that the nicotine received in just a few puffs of a cigarette can exert a force powerful enough to drive an individual to continue smoking. Researchers found that the amount of nicotine contained in just one puff of a cigarette can occupy about 30 percent of the brain’s most common type of nicotine receptors, while three puffs of a cigarette can occupy about 70 percent of these receptors. When nearly all of the receptors are occupied (as a result of smoking at least 2 and one-half cigarettes), the smoker becomes satiated, or satisfied, for a time. Soon, however, this level of satiation wears off, driving the smoker to continue smoking throughout the day to satisfy cigarette cravings. “Imaging studies such as this can add immensely to our understanding of addiction and drug abuse," says Elias A. Zerhouni, M.D., Director of the National Institutes of Health. "These findings suggest that drug therapies or vaccines for smoking cessation need to be extremely potent to compete with nicotine, which binds so readily to these receptors.” The study is published in the August 2006 issue of the Archives of General Psychiatry. “This study illustrates the powerfully addictive impact of even small amounts of nicotine. Every time a smoker draws a puff from a cigarette, they inhale numerous toxic chemicals that promote the formation of lung cancer, and contribute in a significant way to death and disability worldwide,” says NIDA Director Dr. Nora D. Volkow.

Keyword: Drug Abuse; Brain imaging
Link ID: 9216 - Posted: 06.24.2010

Erika Check The 'club drug' ketamine may be the fastest-acting antidepressant ever tested, researchers report today. A team based at the US National Institute of Mental Health (NIMH) in Bethesda, Maryland, studied ketamine in 17 people with major depression. All the subjects had failed to respond to treatment with standard antidepressant drugs or more drastic methods, such as electroshock therapy. But 71% felt better the day after taking ketamine, and 35% still felt better a week later. None improved when dosed with a placebo. Most striking, the scientists say, was that some patients felt better less than 2 hours after taking ketamine. Currently approved drugs can take weeks to remedy depression. The work is published in the Archives of General Psychiatry1. "It's almost like there's a sound barrier for those us who do depression research, and we have not been able to break it," says Carlos Zarate, chief of the mood and anxiety disorders research unit at the NIMH, and first author of the study. "That's the exciting part of this — now there is evidence that we can." Zarate and his colleagues are not advocating that doctors start giving depressed patients ketamine right away. Large doses of the drug can cause brain damage in rodents, and its long-term health effects have not been studied in people. ©2006 Nature Publishing Group

Keyword: Depression; Drug Abuse
Link ID: 9215 - Posted: 06.24.2010

Roxanne Khamsi Exposure to ultrasound while pregnant may affect brain development in the fetus, suggests a study on mice. But experts caution that it is too soon to extrapolate the findings to humans. They stress that the imaging technique has overwhelming benefits and pregnant women should not skip essential appointments. The experiment involved using a chemical to trace brain cells in growing mouse embryos. The researchers exposed the embryos to ultrasound shortly afterward, late into the third week of gestation, a crucial period for mice in which brain cells become organised. Dissections following the birth of the mice showed that a small percentage of brain cells had not migrated to their normal place. For example, 6% of the chemically tagged brain cells had not migrated normally in mice exposed to two 30-minute ultrasound sessions. It may be that the ultrasound waves somehow disrupt the connections formed between cells as they move into their proper location, suggests Pasko Rakic at Yale Medical School in New Haven, Connecticut, US, who carried out the research with colleagues. Rakic says the brains of these mice still appear healthy to the naked eye. Moreover, his team has not yet tested to see whether the mice have abnormal mental abilities. And he notes that the source of the ultrasound waves remained constant, which could have increased the risk of disrupting the cells, unlike in the checkups on female patients where medical staff continuously move the ultrasound source. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Brain imaging
Link ID: 9214 - Posted: 06.24.2010

People who make irrational decisions when faced with problems are at the mercy of their emotions, a study says. Researchers traced the origin of such decisions to the brain's emotion centre, the amygdala, in a study of 20 people using a gambling game. That brain region fires up in people faced with a difficult situation but reactions to its effects vary, the University College London team found. The study findings were published in the Science journal. The researchers found some people kept a cool head and managed to keep their emotions in check, while others were led by their emotional response. In each trial, participants motivated by the promise of real money were first offered a starting amount of £50. They were then presented with one of two "sure option" choices, either to "keep £20", or to "lose £30", as well as the opportunity to take an all-or-nothing gamble. Although both sure options left players with the same amount of cash, £20, people were more likely to gamble when faced with the prospect of losing £30. Given the "keep £20" option, volunteers played it safe and gambled only 43% of the time. When asked if they wanted to "lose £30", they gambled on 62% of occasions. The decision to gamble was irrational, since in every case the amount of money they stood to gain was the same, while everything could be lost by gambling. Brain scans revealed that the amygdala fired up when subjects either chose to keep a sure gain or decided to gamble in the face of certain loss. The brain region, which controls emotion and plays a role in the "fight or flight" reaction to perceived threats, appeared to be pushing people to keep sure money, or to gamble instead of losing. (C)BBC

Keyword: Emotions
Link ID: 9213 - Posted: 08.07.2006

By Tony Dajer "Grandpa fell on knee. Two days before. Pain," the young woman said. Her wizened grandfather dozed on a stretcher. "How are you, sir?" I inquired softly. In loud Cantonese, the granddaughter repeated the question. She smiled apologetically. "No hear good." His eyes fluttered open. When I palmed his right knee, he winced. The joint was swollen, the kneecap scuffed, but he didn't complain when I bent his knee. With the help of an interpreter, I learned that he tripped on his way to the bathroom two days ago. "No dizziness? No passing out? Didn't hit his head?" I asked. A yes to any of these questions would suggest more serious heart or neurological problems. "No," the granddaughter replied. "Only tripped." "He feels OK now?" "OK," she echoed. The rest of his physical exam, except for weakness on his right side due to a previous stroke, was pretty darn good for an 85-year-old man. © 2005 Discover Media LLC.

Keyword: Stroke
Link ID: 9212 - Posted: 06.24.2010