CHAPEL HILL -- By combining the results of 22 studies, University of North Carolina at Chapel Hill researchers have found that a specific form of the gene APOE very slightly increases the risk of Parkinson's disease, even though the same gene is protective in Alzheimer's disease. The researchers also found that the APOE-4 form of the gene, which has long been linked to an increased risk of Alzheimer's disease, is not a risk factor in Parkinson's disease. A report of the findings appears this week in the June issue of the journal Neurology. "It basically shows that neurodegenerative diseases may differ in significant risk factors, contrary to prevailing views," said lead author Dr. Xuemei Huang, assistant professor of neurology in UNC's School of Medicine. The gene APOE refers to apoliprotein E, which takes three forms, or alleles: APOE-2, -3 and -4. These and other APO genes transcribe apolipoproteins, protein particles involved in lipid metabolism that shuttle these fatty acids, including cholesterol, through the body. "APOE-4 is a major susceptibility gene for sporadic and familial Alzheimer's disease and has been associated with poor clinical outcome in people with acute head injury and stroke," Huang said. "In the brain, apolipoprotein E-4 may be involved in neuron repair and in the removal of dead cells, so if you have APOE-4, you may be at higher risk of Alzheimer's disease or poor recovery from stroke and brain injury."

Keyword: Parkinsons; Alzheimers
Link ID: 5703 - Posted: 06.24.2004

The fat-tailed dwarf lemur has become the first primate proven to hibernate through the winter. The rat-sized lemur curls up in tree holes to slumber through the dry winter season, despite living in tropical Madagascar, where winter temperatures can still exceed 30°C. It spends seven sleepy months living off the fat of its portly tail. But until now its disappearance during the winter had been a matter of speculation, and lab studies had been unable to get the lemurs to hibernate. Kathrin Dausmann at Phillips University, Marburg, Germany, and her colleagues have now proven that the lemurs really do hibernate - and they are the first primates and tropical animals to show this behaviour. The team observed the physiological changes that the lemurs undergo. Unlike other hibernators, the lemurs do not regulate their body temperatures whilst dormant. The temperatures vary widely - by almost 25°C - and are determined by how well or badly the primates' tree holes are insulated. © Copyright Reed Business Information Ltd.

Keyword: Biological Rhythms
Link ID: 5702 - Posted: 06.24.2010

BOSTON - A genetic mutation in "mighty mice" is also found in a German boy with unusually large muscles, scientist say. The four-year-old's muscles are roughly twice as large as other children his age. Researchers found he has an inherited mutation in the myostatin gene, boosting muscle growth and reducing fat. "This is the first evidence that myostatin regulates muscle mass in people as it does in other animals," said Dr. Se-Jin Lee, a professor of molecular biology and genetics at Johns Hopkins University in Baltimore, and a co-author of the study. Naturally bulky cattle such as Belgian Blues also lack myostatin, the researchers have found. Lee's team wants to explore if interfering with myostatin can slow down muscle loss in muscle wasting diseases such as Duchenne muscular dystrophy. About 850 males in Canada have the disease. Seven years ago, Lee's team created mice that are twice as brawny as normal by blocking the mysotatin gene. Both Lee and his university would share in royalties if the research results in any commercial therapies. Copyright © CBC 2004

Keyword: Muscles
Link ID: 5701 - Posted: 06.24.2010

BY JAMIE TALAN Can't keep a tune? You may get to blame your brain. People who can't discriminate between musical tones suffer from amusia, or tone deafness, and Canadian researchers say they have identified a region in the brain they believe is responsible. They are set to deliver preliminary findings today at an international meeting in Montreal on music and the brain. Krista Hyde and her colleagues at the University of Montreal have been scanning the brains of 20 people who've been tone deaf since birth, and have narrowed the hunt to the right auditory cortex, an area of the brain that processes pitch perception. Amusia is no laughing matter, Hyde, a doctoral student, says. Music is such a major element of our culture, she said, that the condition "robs them of their experience of music. ... A beautiful symphony can sound like noise." The researchers suspect that as much as 4 percent of the world's population have a congenital brain abnormality that renders them tone deaf. Others can acquire amusia following head trauma or stroke. Of 100 people who responded to ads seeking people who can't carry a tune, Hyde said only 20 qualified for a true diagnosis of amusia - indicating many who think they're tone deaf instead simply aren't good vocalists. Copyright © 2004, Newsday, Inc.

Keyword: Hearing
Link ID: 5700 - Posted: 06.24.2010

Smoking cigarettes cuts an average of 10 years off a person's life, a landmark study suggests. But it also shows that quitting at any age reduces the risks of dying from smoking-related diseases. The findings, published in the British Medical Journal, are the culmination of a 50-year study involving 34,439 men. The study, which began in 1951, was the first to confirm the link between smoking and lung cancer exactly 50 years ago. All of those involved in the study were born between 1900 and 1930 and all worked as doctors. They were each asked about their smoking habits at the start of the study in 1951. Researchers contacted them periodically over the next 50 years to see if those habits had changed. They also gathered information on those who died during the period. They have now analysed that data. They found that men who have never smoked lived on average 10 years longer than those who smoked for most of their lives. Men who smoked were at least twice as likely to die before the age of 70 as non-smokers. They were up to three times more likely to die before they were 90 compared to those who never took up the habit. (C)BBC

Keyword: Drug Abuse
Link ID: 5699 - Posted: 06.23.2004

By ANAHAD O'CONNOR THE FACTS Most Americans relish the thought of sleeping late, and experts have traditionally recommended eight hours of rest each night. But a 2002 study found that getting more than seven hours of sleep each night was associated with a shorter life span. Several studies since then, including one this year by researchers at Brigham and Women's Hospital in Boston, also found a link. The 2002 study examined data on more than a million Americans over the age of 30 between 1982 and 1988. The risk of dying in that period climbed as subjects went above seven hours of sleep. Those who averaged eight hours a night, the study found, had a 12 percent increased chance of death. Other researchers have also found that life expectancy declines as sleep falls below seven hours, but not as steeply as it does with eight hours or more, said Dr. Jerome M. Siegel, of the University of California, Los Angeles. Most sleep experts are reluctant to draw conclusions because the findings are based on correlations, which cannot show cause and effect. People who sleep longer may have illnesses that cause fatigue and earlier death. THE BOTTOM LINE Averaging more than seven hours of sleep a night is associated with a shorter life span, though whether poor health or too much sleep accounts for the link is unclear. Copyright 2004 The New York Times Company

Keyword: Sleep
Link ID: 5698 - Posted: 06.23.2004

Poets and songwriters will be devastated to hear it: The eyes don't smile after all. Neither do they sadden, according to new research using Mona Lisa's portrait. Those two emotions are the domain of the mouth, it turns out. Similar research could help pinpoint other emotions, or help determine the brain defects in people with visual problems such as the inability to recognize faces. Human facial expressions are subtler than they look, and it's hard to determine the source of emotional information. One technique researchers have used is to show volunteers parts of a face and ask what emotion they see. A different technique allows expressions to "evolve" on an image, allowing researchers access to the whole expression at once. To determine what features make people look happy or sad, visual neuroscientists Christopher Tyler and Leonid Kontsevich of the Smith-Kettlewell Eye Research Institute in San Francisco evolved expressions on The Mona Lisa. The researchers added noise to her ambiguous expression, making the image look like a fuzzy TV screen, then asked subjects to rate her emotion on a four-point scale of happy to sad. The researchers then averaged all of the noisy images in each category of emotion, revealing the subtleties in the facial features needed to spell out happiness or sadness. To determine whether the eyes and the mouth worked together to evoke emotion, the team laid the composite happy or sad noise on just the upper or lower half at a time. Overlaying the mouth half caused Mona to grin or frown, but overlaying the eyes conveyed no emotion. The researchers replicated the finding with a photograph of a woman with an ambiguous expression. "The eyes are well-known to be the window on the soul, so we expected to see an effect of the eyes," says Tyler. Instead, the eyes might express intensity, he speculates. "Perhaps they are the window on the spirit." Visual psychophysicist Richard Murray of the University of Pennsylvania in Philadelphia is also surprised. In addition to learning about expressions, "we can use this technique on people with visual deficits to determine what's going wrong in their brain," he says. --MARY BECKMAN Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Emotions
Link ID: 5697 - Posted: 06.24.2010

Cameron Walker for National Geographic News With 66.3 million fathers in the United States, neckties may be flying out of the store this week in anticipation of Father's Day. It's a great time to appreciate Dad for years of service—teaching you to drive a stick, helping you buy your first home, or even showing you how to work a Windsor knot on your very own tie. But there are a slew of lesser-known fathers in the animal kingdom with intensive parenting skills of their own. "The whole point for the parents is to get at least two offspring to survive," said Ed Matheson, an ichthyologist (fish zoologist) at the Florida Marine Research Institute in St. Petersburg. And for some species, the male's the one that helps his young—and the genes they're carrying—safely weather the often dangerous path toward adulthood. Once the female hip-pocket frog, an Australian species also known as the marsupial frog, lays up to 20 white eggs, her work is done. According to Frank Lemckert, a research scientist for the State Forests of New South Wales, Australia, the female then "heads off to do whatever she wants to do, perhaps finding a mate and laying more eggs" the male gets day care duty. Over a period of several days, the male frog watches the eggs hatch into tiny tadpoles. Then the male takes a seat right in the middle of the new tadpoles. The tadpoles wriggle along their father's back until they reach two tiny slots that open into the male's hip pouches. © 2004 National Geographic Society. All rights reserved.

Keyword: Sexual Behavior
Link ID: 5696 - Posted: 06.24.2010

Older women using estrogen-alone hormone therapy could be at a slightly greater risk of developing dementia, including Alzheimer's disease (AD), than women who do not use any menopausal hormone therapy, according to a new report by scientists with the Women's Health Initiative Memory Study (WHIMS). The scientists also found that estrogen alone did not prevent cognitive decline in these older women. These findings from WHIMS appear in the June 23/30, 2004, Journal of the American Medical Association*. "These studies further support last year's recommendations that menopausal hormone therapy should not be used to prevent cognitive decline or dementia in older postmenopausal women," stated Judith A. Salerno, MD, MS, Deputy Director of the National Institute on Aging (NIA). "Women should follow the Food and Drug Administration's recommendation that those who want to use menopausal hormone therapy to control their menopausal symptoms should use it at the lowest effective dose for the shortest time necessary." The latest findings were reported by WHIMS Principal Investigator Sally A. Shumaker, PhD, Wake Forest University School of Medicine, and her colleagues at the 39 study sites. This research was funded by Wyeth Pharmaceuticals, which manufactures Premarin™, the conjugated equine estrogens used in this trial, and Wake Forest University Baptist Medical Center.

Keyword: Alzheimers; Hormones & Behavior
Link ID: 5695 - Posted: 06.23.2004

Early humans evolved the anatomy needed to hear each other talk at least 350,000 years ago. This suggests rudimentary form of speech developed early on in our evolution. The conclusion comes from studies of fossilised skulls discovered in the mountains of Spain. A team of Spanish and US researchers used CT scans to measure the bones and spaces in the outer and middle ears of five specimens, thought to belong to Homo heidelbergensis. This species is thought to be a relative of the ancestral line leading to neanderthals. The team worked out how well the hearing apparatus they found could respond to sounds of various frequencies. The hominids' ears would have been sensitive to frequencies between two to four kilohertz, the range most important for understanding human speech. Chimpanzees' ears are relatively insensitive at those frequencies. Their ears are most strongly attuned to sounds peaking at either one kHz or eight kHz. © Copyright Reed Business Information Ltd.

Keyword: Language; Evolution
Link ID: 5694 - Posted: 06.24.2010

Virtual reality appears to dramatically change how the brain physically registers pain, not just how people subjected to pain perceive the incoming signals, according to a new study by a group of University of Washington researchers. The work, which used a specialized type of magnetic resonance imaging to track pain-related brain activity, showed drops of as much as 97 percent in such activity in some brain centers. The study marks the first time that scientists have documented a link between virtual reality and pain reduction in terms of an actual physiological response. "What this study shows is that virtual reality is not only changing the way people interpret the incoming pain, it is changing the actual activity in the brain," said Hunter Hoffman, director of the VR Analgesia Research Center at the UW's Human Interface Technology Laboratory, a facility affiliated with the university's College of Engineering. The paper appears in the current issue of the journal NeuroReport. The findings support those of an earlier study by Hoffman and Dave Patterson, a psychologist and pain expert at Harborview Medical Center in Seattle, in which patients were asked to rate their levels of pain while being treated for severe burns, both with and without virtual reality. Patients immersed in a virtual world during the often-excruciating therapy reported a 40-percent to 50-percent drop in pain.

Keyword: Pain & Touch
Link ID: 5693 - Posted: 06.23.2004

Study shows that the brain codes information unconsciously for basic eye movements Temporary rapidly induced blindness has provided evidence that an older, primitive part of the brain plays a role in processing visual information unconsciously. This finding by researchers at Houston's Rice University was published in the Proceedings of the National Academy of Sciences online this week (www.pnas.org). For the study, six volunteers with normal vision underwent more than 600 trials in which they had to look at a target placed at varying locations on a computer screen. For half of the trials, the participants were asked to move their eyes to the location of the target, and their eye movements were measured electronically. For the other half, the participants were asked to press a button that corresponded with the location of the target on-screen. During the trials, the researchers sometimes tried to distract them with an item shown on the center of the screen. Response time was recorded for each trial. Prior to the tests, the researchers mapped each participant's visual cortex – the area at the back of the brain that processes what the eye sees – with transcranial magnetic stimulation (TMS), a harmless noninvasive technique using brief magnetic pulses. When applied to the visual cortex, TMS induces temporary, reversible blindness lasting only a fraction of a second.

Keyword: Vision
Link ID: 5692 - Posted: 06.24.2010

By Kimberly W. Moy, Globe Correspondent Two years ago Mark Rocheford of suburban Minneapolis had a stroke that damaged his memory, paralyzed his left side and left him partially blind. Rocheford, now 56, underwent extensive rehabilitation within months of his stroke, but, as of April, his left hand was still ''pretty much useless." Frustrated, Rocheford volunteered to be part of an experimental ''homework" program for stroke patients. He spent up to four hours a day playing a computer game designed to get him to exercise his left hand. In two weeks of game-playing, he made as much progress as in the previous two years, regaining the ability to point, grab the handle of a pulley exercise system, and touch each finger to his thumb. ''He showed me all the stuff he could do, and I was amazed," said Rocheford's 21-year-old daughter Erin, who observed her father during weekend breaks from college. The program is part of a small but growing trend in health care to harness home computers to supplement regular visits with a therapist or a counselor. Home-based computer therapy programs are now under design across the country to help stroke victims, people with psychological problems, and disabled children, among others. © 2004 The New York Times Company

Keyword: Stroke; Regeneration
Link ID: 5691 - Posted: 06.24.2010

More people die of lung cancer than of colon, breast, and prostate cancers combined, making it the leading cause of cancer death for both men and women. Currently, there are no approved screening tests for lung cancer in the U.S. "One of our greatest challenges as pulmonary physicians is trying to identify [the] subset of smokers who are likely to develop lung cancer," says Avrum Spira, pulmonary physician at Boston University Medical Center. "If you look at the statistics, roughly 10 to 15% of people who smoke will develop lung cancer over their lifetime. There's no way to identify that 10 or 15 percent that are on their way to developing lung cancer." With the goal of finding preventative measures, Spira and his team compared the DNA in cells scraped from the windpipes of 75 smokers, former smokers, and nonsmokers. His study, published in the Proceedings of the National Academy of Sciences, showed that smoking causes damage at the genetic level, permanently altering several genes associated with tumors and cancer. "No one knows the exact genetic…damage that ultimately leads to lung cancer," Spira says. "What is known is that toxins in the environment—cigarette smoke being the principle one, but there are others, including asbestos and radon—are inhaled, go into the lung tissue…and they actually induce mutations in some of the DNA. The cells…change the way they look under the microscope, and eventually they start growing out of control—that is, the ability to control the division of the cell is lost," he says. "A single cell actually undergoes enormous expansion and grows within the lung and eventually leads to the demise of the patient." © ScienCentral, 2000-2004.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 5690 - Posted: 06.24.2010

Doctors may now be able to explain why ex-smokers retain a lifelong risk for lung cancer. Researchers have discovered that the onslaught of cigarette smoke causes 97 genes to malfunction. Kicking the habit lets most genes return to normal function over time, but some are damaged forever. Cigarette smoke is the leading cause of cancer deaths worldwide. Frustratingly, although lung cancer responds well to treatment if caught early, there is currently no screening test available for the disease--doctors simply don't know what to look for yet. However, thanks to advances in genome data collection, that may change. In search of early markers of lung cancer, pulmonary and critical care physicians Avrum Spira and Jerome Brody of the Boston Medical Center sampled bronchial tube epithelial cells from 85 people. The study, reported in the 21 June issue of the Proceedings of the National Academy of Sciences, included 34 smokers, 18 former smokers, and 23 people who had never smoked. The team isolated RNA from the cells and looked for patterns in gene expression. Ultimately, the team identified 97 genes that function differently in smokers. Cell detoxification, airway inflammation control, and tumor suppression were dampened while cancer-causing gene activity increased. As expected, gene expression was most severely affected in the heaviest smokers. The team found no difference in gene function based on age or gender. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 5689 - Posted: 06.24.2010

Some dogs can predict when a child will have an epileptic seizure, a new study has revealed. These dogs not only protect their charges from injuries, such as falling, but also seem to help kids deal with the daily struggle of epilepsy. Nine of the 60 dogs in the study (15 per cent) were able to predict a seizure by licking, whimpering, or standing next to the child. These dogs were remarkably accurate - they predicted 80 per cent of seizures, with no false reports. However, those interested in owning a dog with these skills cannot yet just order one. The dogs were not trained, but instead began predicting seizures spontaneously within a month of moving in with their owners. "No one is reliably training such dogs yet," says Adam Kirton, a neurologist at Alberta Children's Hospital in Canada and lead author of the study. His group is looking into setting up a training program. However, some epilepsy patients do have already dogs that have been trained to protect them during a seizure. © Copyright Reed Business Information Ltd

Keyword: Epilepsy
Link ID: 5688 - Posted: 06.24.2010

DURHAM, N.C. -- The first sensory map of the fly equivalent of a tongue suggests that insects have discriminating taste -- perhaps trumping that of mammals in the ability to differentiate among bitter flavors. The findings could ultimately prove useful in the development of improved pest repellants, said the Duke University Medical Center researchers. According to the team's analysis, specialized cells in the fruit fly's primary taste organ, the labellum -- a structure on the fly's head that looks like a pair of lips covered in bristles -- respond to either sweet or bitter flavors, much like cells of the human tongue. However, while earlier work suggested mammalian bitter tasting cells are all alike, the Duke researchers found that different sets of bitter-sensitive nerve cells on the fly "tongue" bear distinct combinations of taste receptors, the Duke team found. Receptors are the protein switches that trigger the nerve cells to send signals to the brain's taste-processing centers in response to particular food items or other chemicals. The unique coding of the flies' tasting cells raises the possibility that insects can discern among different bitter tastes more precisely than can humans or other mammals, said Hubert Amrein, Ph.D., assistant professor of genetics and lead author of the study. Amrein and his colleagues reported their findings in the June 22, 2004, issue of Current Biology. The work was supported by the National Institutes of Health. © 2001-2004 Duke University Medical Center.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 5687 - Posted: 06.24.2010

Transgenic carrier inactivates cocaine in rat brains. LAURA NELSON A cure for cocaine addiction is one step closer. A method has been developed of mopping up the drug in the brain so that it produces less euphoria. Scientists hope that addicts will be less inclined to keep taking the drug if they do not get their hit. The idea of inactivating cocaine once it is in the body is not new. One approach is to inject addicts with antibodies that bind to the drug, in an attempt to counteract its powerful effect. Previously, these antibodies were unable to get into the brain, so the effect of the treatment was limited. The new method uses a virus that invades the brain to deliver the antibodies. “It’s a neat idea,” comments Arnold Ruoho, a pharmacologist at the University of Wisconsin–Madison. The virus is safe, he says, because any harmful gene sequences have been removed, but genes for the appropriate antibodies have been inserted into the virus’s genome. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Drug Abuse
Link ID: 5686 - Posted: 06.24.2010

EVANSTON, Ill. --- A Northwestern University study is the first to suggest that delayed brain development and its interaction with puberty may be key factors contributing to language-based learning disabilities such as dyslexia. The article will appear in the online edition of the Proceedings of the National Academy of Sciences (PNAS) the week of June 21. In "Learning Problems, Delayed Development and Puberty," co-authors Beverly A. Wright and Steven G. Zecker provide a new and overarching developmental hypothesis that could change the way that these disabilities, that affect one out of 12 children with normal intelligence, are studied, understood and treated. The authors are associate professors of communication sciences and disorders at Northwestern. "Approaching learning disabilities from the perspective of brain development could potentially unite many seemingly disparate deficits observed in adults with learning problems -- from evidence that their white brain matter is abnormally distributed to findings that they have difficulty distinguishing and manipulating language sounds," said Wright. The idea of brain delay also could help explain anecdotal evidence that learning disabled children toilet train late, have difficulty learning to ride a bicycle, talk later and generally appear less developmentally mature than their unaffected counterparts.

Keyword: Dyslexia; Development of the Brain
Link ID: 5685 - Posted: 06.22.2004

St. Paul, Minn. – Researchers have new insights into a mysterious type of amnesia, according to a study published in the June 22 issue of Neurology, the scientific journal of the American Academy of Neurology. The study showed lesions didn’t appear immediately in the patients’ brains, but developed one to two days after an episode of transient global amnesia. Using diffusion weighted imaging, a type of MRI, a team in Germany examined 31 patients within hours of the onset of amnesia. In a new approach, the patients underwent two follow-up MRI studies over the next two days. After 24 hours, small lesions (areas of brain damage) appeared on the MRI for 23 patients, and after 48 hours, lesions appeared for three more patients. All lesions were located in the hippocampus, an area of the brain which plays an important role in memory functions. In two of the five patients without lesions, the MRI was done after 96 and 120 hours. Transient global amnesia is characterized by a sudden inability to form new memories or recall the near past. This amnesia often occurs following a stressful, emotional situation, and usually lasts less than 24 hours. There are no apparent long-term effects. The cause isn’t yet known. None of the patients studied had recent history of head injury or seizures. Despite some similarities, transient global amnesia isn’t the same as a transient ischemic attack (TIA). Lesions from TIA typically appear larger in size and without delay, in contrast to lesions associated with transient global amnesia.

Keyword: Learning & Memory; Stroke
Link ID: 5684 - Posted: 06.24.2010