By Jennifer Viegas, Discovery News — Scientists have taught dolphins to combine both rhythm and vocalizations to produce music, which has resulted in an extremely high-pitched, short version of the "Batman" theme song. The findings, outlined in two studies, represent the first time that nonhuman mammals have demonstrated that they can recognize rhythms and reproduce them vocally. "Humans are sensitive to rhythms embedded in sequences of sounds, but we typically consider this skill to be part of processing for language and music, cognitive domains that we consider to be uniquely human," said Heidi Harley, lead author of both studies. "Clearly, aspects of those domains are available to other species." The studies will be presented at the joint meeting of the Acoustical Society of America and NOISE-CON 2005, which runs from Oct. 17-21 in Minneapolis. Harley, who is associate professor of social sciences at the New College of Florida in Sarasota, told Discovery News that both studies tested dolphins at The Living Seas exhibit at the Disney World Resort's Epcot Center in Lake Buena Vista, Fla. © 2005 Discovery Communications Inc.

Keyword: Hearing; Evolution
Link ID: 7970 - Posted: 06.24.2010

Michael Hopkin Gorillas have been spotted using tools in the wild for the first time, after decades of observation. Researchers in the Congolese jungle saw one of the great apes using a branch to test the depth of a pond, and another using the trunk of a small shrub as an improvised bridge. Unlike chimpanzees, which use a range of tricks to get food, gorillas rely more on size and strength: they shell nuts with their teeth, or smash open termite mounds with their fists. But not needing tools to get food does not mean that gorillas aren't smart enough to use them. Captive western gorillas (Gorilla gorilla) are known to use tools in captivity, for example. And mountain gorillas (G. beringei) use a variety of different techniques which, although not involving tools, are clever ways of stripping leaves from hard-to-reach plants. The new observations show that western gorillas have the mental wherewithal to use tools to solve other problems too, such as navigating through an ominously deep-looking pond, says Thomas Breuer of the New York-based Wildlife Conservation Society, and a member of the team that spotted the innovative behaviour. ©2005 Nature Publishing Group

Keyword: Evolution
Link ID: 7969 - Posted: 06.24.2010

By BENEDICT CAREY The popular antidepressant Paxil may increase the risk of birth defects if pregnant women take it during the first trimester, federal health officials announced late Tuesday. The Food and Drug Administration posted the warning on its Web site after the drug's manufacturer, the British company GlaxoSmithKline, sent the agency and doctors a letter that cited evidence from a new study. Glaxo said in the letter that it had changed the drug's label to reflect the possibility of the increased risk. Some doctors who read the letter said it was not clear whether the F.D.A.'s warning was necessary. The Glaxo study was an analysis of medical records from a managed care company, and did not provide convincing evidence that it was the drug, and not some other factor, that was responsible for the increased risk, they said. "Typically in studies like this you can't control for other things that could have contributed to the increased rate of defects, like the severity of the mother's depression," said Dr. Timothy Oberlander, a developmental pediatrician at the University of British Columbia and BC Children's Hospital in Vancouver. The F.D.A. is reviewing the study, said Susan Cruzan, a spokeswoman for the agency. Copyright 2005 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 7968 - Posted: 09.29.2005

We all age, it's a fact of life, like death and taxes, and there's nothing we can do about it. But, how is it possible that of two middle-aged mice, one is already grey, balding and frail? Researchers have discovered that genetic mutations in the powerhouses of our cells — mitochondria — appear to trigger cells to die and speed up the aging process. Inducing these kinds of mitochondrial mutations leads to premature aging in mice, which live only about half as long as normal mice. Geneticist Tom Prolla and his group at the University of Wisconsin-Madison created the fast-aging mice by altering just two of the thousands of letters, or bases, of the mouse DNA code. That changed a gene, called polymerase gamma, in the energy-producing mitochondria. "This gene basically functions as a spellchecker during the copying of mitochondrial DNA," he explains. "So we altered two bases in the gene and made it defective, so that it… can no longer function as a spell-checker. So as a result of that the mitochondrial DNA accumulates mutations." At first the mice looked normal, but around eight or nine months of age the researchers began to notice differences. "We started seeing a lot of aging symptoms in them, such as hair loss, greying, loss of bone mass, loss of muscle mass, problems in the spinal curvature," Prolla says. "The equivalent age for a human would be 30 years old when they show a lot of these aging symptoms, so they really age very fast." © ScienCentral, 2000-2005.

Keyword: Alzheimers
Link ID: 7967 - Posted: 06.24.2010

Betsy Leohner does not live in constant fear, but in the back of her mind, she is worried she will loose her mind. Her mother died of Alzheimer's disease at 83, and now her sister has been diagnosed with the disease. "It isn't something I worry about everyday, but when I forget something, I think oh, is this it," says Leohner who is 67, but looks much younger and has yet to show any symptoms of the disease. There is no way of predicting whether Leohner will ultimately develop Alzheimer's, but brain researchers based in New York and Florida have made an intriguing finding that may set people like Leohner at ease. Scientists led by Albert Einstein College of Medicine microbiologist Luciano D'Adamio found a gene that may control the production of beta amyloid plaques — protein deposits that collect along the outer borders of brain cells in some Alzheimer's patients, and which are thought to be associated with the disease's symptoms. The gene is called BRI2 (BREE-TWO). Previous research has shown that in two rare types of inherited dementia, known as British Dementia and Danish Dementia and which are akin to Alzheimer's disease, the gene is mutated and there are subsequently increased amounts of beta amyloid plaques. It is not known whether these plaques are themselves a cause of the three diseases or simply a consequence of them. It is also doubtful BRI2 is the only gene controlling plaque production, but the researchers hope that by understanding one way they are produced, they may ultimately be able to develop drugs that could prevent the diseases or at least slow their symptoms. © ScienCentral, 2000-2005.

Keyword: Alzheimers
Link ID: 7966 - Posted: 06.24.2010

Alcoholics who smoke appear to lose more brain mass than alcoholics who don't smoke, according to a study at the San Francisco VA Medical Center. It is already well-known that the brains of long-term alcoholics atrophy and shrink, the study authors say, but the new findings are the first evidence that cigarette smoking might contribute to that atrophy, particularly in grey matter of the parietal and temporal lobes. Fifty to 90 percent of alcoholics also are smokers, according to Dieter Meyerhoff, PhD, a radiology researcher at SFVAMC and the principal investigator of the study "Just looking at the amount of tissue mass lost due to either drinking or smoking, alcoholics who smoke show a greater loss in some regions of the brain compared to alcoholics who don't smoke," says Meyerhoff, who also is a professor of radiology at the University of California, San Francisco. The study, which was published in the August 2005 issue of Alcoholism: Clinical and Experimental Research, compared 37 recovering alcoholics between the ages of 26 and 66 with a control group of 30 healthy light drinkers. The researchers used magnetic resonance imaging, a safe, non-invasive imaging technique, to measure brain volumes of the study participants. They discovered that the more severe the tobacco habit, the greater the brain injury. "In smoking alcohol-dependent individuals, smaller regional [brain] volumes are related to greater cigarette-smoking severity," according to the study findings, with severity measured by level of nicotine dependence, cigarettes smoked per day, and years of smoking.

Keyword: Drug Abuse
Link ID: 7965 - Posted: 09.29.2005

Medication should not be readily dished out to children and young people with depression, say experts. The National Institute for Health and Clinical Excellence (NICE) has ruled drugs should be considered only in moderate or severe cases. The NHS drug watchdog said young people should first be offered a course of psychological therapy lasting for at least three months. Campaigners say this is not happening as therapists are in short supply. Research by the charity Sane found over 80% of young people with depression are given medication and only 6% any form of psychiatric therapy. The NICE guidance stressed drugs should only be offered in tandem with, and not instead of, therapy. Most of a class of anti-depressants called SSRIs have already been barred from use in young people in the UK over concerns of a heightened risk of suicide. NICE also warned many young people with depression are not being diagnosed - putting them at increased risk of self-harm and suicide. It said healthcare professionals in primary care, schools and other relevant community settings should be trained to detect symptoms of depression, and to assess children and young people who may be at risk. And the guidance emphasised that in some cases parents' psychiatric problems need to be treated in parallel if a young person's mental health is to improve. (C)BBC

Keyword: Depression; Development of the Brain
Link ID: 7964 - Posted: 09.28.2005

By NICHOLAS WADE Linguists have devised a new way of linking languages, which they say has allowed them to reconstruct a network of the languages spoken in islands near New Guinea. The new method is designed for languages so old that little trace of their common vocabulary remains. It forges connections between languages through grammatical features, which change less quickly than words. With the new tool, historians may be able to peer considerably further back in time than the 5,000 to 7,000 years or so that many linguists see as the limit beyond which no sure connections can be made between languages. The authors of the new method say the relationships they can construct may be 10,000 years or older. The researchers, who were led by Michael Dunn, of the Max Planck Institute for Psycholinguistics in Nijmegen, Holland, have published their work in the current issue of Science. They say that on the basis of grammatical similarities they have constructed a network of the Papuan languages spoken in the island groups east of Papua New Guinea. Traveling eastward, these are the Bismarck Islands, Bougainville and the Solomon Islands. Copyright 2005 The New York Times Company

Keyword: Language
Link ID: 7963 - Posted: 09.28.2005

By Steven Ashley Shortly after terrorist bombs ripped through central London's transit system on July 7, Scotland Yard dispatched trained sniffer dog teams to search for explosives and to scent out clues at the blast sites. Meanwhile, less than an hour up the M11 highway in Cambridge, engineers Billy Boyle, Andrew Koehl and David Ruiz-Alonso were lamenting the fact that the antiterrorist technology they had worked on since just after 9/11--a sensitive but inexpensive electronic nose--had not been ready to help avert this tragedy. The Ph.D. engineers have developed a button-size chemical sensor prototype that is designed, among other things, to detect trace amounts of explosives before they detonate. The prospect of a modern-day coal-mine canary for trains and buildings still lies in the future for the entrepreneurial brain trust of Owlstone Ltd., the University of Cambridge spin-off company the trio established two years ago. But backed by $2 million in venture-capital funding, the device should be ready for field tests this fall. The three are confident that the low-power device can quickly identify tiny concentrations of substances in parts per billion. "Our idea is to put one on the lapel of every soldier and in every Tube carriage," Boyle states. The R&D effort started in late 2001, when Koehl, an electrical engineer, arrived at Cambridge from the California Institute of Technology. "From the beginning, I had the idea to create a small, cheap chemical detection system for the military and Homeland Security and then, later, for commercial markets," Koehl says. © 1996-2005 Scientific American, Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 7962 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — All brains originated from a single common ancestral brain that emerged at least 700 million years ago, according to a recent analysis of brain studies from the past decade. The finding suggests this mother brain for all creatures with a central nervous system — such as insects, birds, animals and humans — evolved only once before each species underwent its own evolutionary course. "What we see today in humans, insects and all other multicellular animals with a central nervous system are probably just variations of one ancient scheme," said Rudi Loesel, who conducted the analysis. Loesel, a scientist in the Department of Developmental Biology and Morphology of Animals at RWTH Aachen University in Germany, added, "What this ancestral brain looked like, we do not know. Its architecture might have been very simple, but the basic genetic mechanisms and the principal chemical setup was already there (before 700 million years ago)." The researchers don't know what the creature that contained the mother of all brains looked like. Some scientists speculate that it could have been a segmented flatworm, while others think it was a more complex creature. © 2005 Discovery Communications Inc

Keyword: Evolution
Link ID: 7961 - Posted: 06.24.2010

Michael Hopkin Computer scientists have created a hat that can read your thoughts. It allows you to stroll down a virtual street. All you have to do is think about walking. Called a brain-computer interface, the device detects activity in certain brain areas linked to movement, and uses the signals to mimic that movement in a virtual world. The technology could one day help paralysed patients to move robotic arms, or help sufferers of motor neuron disease to type out words on a virtual keyboard. "Just thinking about movement activates the same neurons as actually moving," explains Gert Pfurtscheller of Graz University of Technology in Austria, who has been working on the device for around four years. By picking up on these bursts of nerve activity, the computer can decide whether you are thinking about moving your hands or feet, and react accordingly. The technology detects brain waves by using electrodes placed at strategic points on the scalp; they are positioned over brain areas known to be involved in moving specific body parts. The computer can then distinguish between signals corresponding to different types of movement. Previously, accurate detection of local brain activity has required electrodes to be implanted in the brain. This technique has allowed recipients to control robots and even send e-mails (see "Paralysed man sends e-mail by thought ") . The new device, presented at the Presence 2005 technology meeting in London last week1, achieves a similar feat using non-invasive methods. ©2005 Nature Publishing Group

Keyword: Regeneration
Link ID: 7960 - Posted: 06.24.2010

By Gill Higgins Justin Richardson was an American student passionate about sport. But one night, a reckless dive into a shallow pool broke his neck. He was paralysed from the chest down and faced a life with no sensation at all in his lower limbs. But an experimental treatment appears to have made a difference. Justin says: "I can now feel most every single spot of my body. And I have my bladder control back now. I know when I need to use the rest room, which has improved my independence." Spontaneous recovery can occur. But Justin believes it is the treatment which has helped him. His medical team have been impressed. Therapist Rebecca Czarnecki, Spinal Cord Fitness Coordinator at the WakeMed Rehab Centre in North Carolina says: "Justin compared to other patients with a similar injury is above and beyond their ability." The treatment, called Procord, uses a type of white blood cell, called a macrophage, which is taken from the patient themselves. When an injury occurs in most parts of the body, such as a wound to the hand, the immune system activates a healing processes, in which macrophages play a part. This does not happen in the central nervous system, including the spinal cord, which is protected by the blood-brain barrier, a defence system blocking foreign substances in the body from reaching the nervous tissue. (C)BBC

Keyword: Regeneration; Glia
Link ID: 7959 - Posted: 09.27.2005

Temperature triggers significant changes in the expression of specific clock genes. The biological clock controls the circadian rhythms of a wide range of physiological and behavioral processes, from fluctuating hormone levels to sleep–wake cycles and feeding patterns. While it's well known that circadian clock elements sense and respond to light cycles, much less is known about how daily temperature cycles affect the clock's timing mechanism in vertebrates. In the open-access journal PLoS Biology, Kajori Lahiri, Nicholas Foulkes, and their colleagues study temperature related responses at the genetic and molecular level in zebrafish. This genetically tractable model organism is especially suited to this task because adults, larvae, and even embryos can tolerate a wide range of core body temperatures (being cold-blooded animals) that can be manipulated simply by changing the water temperature. Temperature variations of as little as 2 ºC (35.6 ºF) can reset the zebrafish clock, Lahiri et al. show, and precise shifts in temperature trigger significant changes in the expression of specific clock genes. More explicitly, clock genes per4, cry2a, cry3, and clock1 showed rhythmic expression under temperature cycles when animals were raised in the dark, and the expression profiles during the high temperature phase matched those seen during a light phase when animals experienced light-dark cycles.

Keyword: Biological Rhythms
Link ID: 7958 - Posted: 06.24.2010

Carl T. Hall, Chronicle Science Writer New evidence from mouse studies suggests that stem cells may help cure paralysis in cases of spinal cord injury. So that raises an obvious question: When can they be tried in humans? The answer: No time soon. That may be disappointing to paralyzed individuals with untreatable spinal cord damage, as well as champions of California's Proposition 71 stem cell research program, all anxious to see real treatments develop from the hype of regenerative medicine. But experts warn it would be a big mistake to rush into clinical trials before settling the many scientific and ethical issues clouding the future of stem cell biology. "I fully understand the impatience of patients, spinal cord injury patients in particular, who are desperate for some form of treatment. But there is risk proceeding too quickly here," said Dr. Arnold Kriegstein, a neurologist who serves as director of a stem cell and tissue biology program at UCSF. "The whole field could be damaged by the outcome of one failed early trial," he said. "I am not saying (a human trial) shouldn't be done, but we should really be cautious about it." ©2005 San Francisco Chronicle

Keyword: Regeneration; Stem Cells
Link ID: 7957 - Posted: 06.24.2010

SEATTLE – One teenager likes to snowboard off a cliff. Another prefers to read a book and wouldn't think of trading places. Why these differences exist is a mystery, but for the first time researchers have identified a possible genetic explanation behind risk-seeking behavior. Scientists at Fred Hutchinson Cancer Research Center have found that a specific neurodevelopmental gene, called neuroD2, is related to the development of an almond-shaped area of the brain called the amygdala, the brain's emotional seat. This gene also controls emotional-memory formation and development of the fear response, according to research led by James Olson, M.D., Ph.D., associate member of the Clinical Research Division at the Hutchinson Center. The findings will be published in the early online edition of the Proceedings of the National Academy of Sciences the week of Sept. 26. Olson and colleagues studied mice with a single copy of the neuroD2 gene and found they had an impaired ability to form emotional memories and conditioned fear. "Most of us are familiar with the fact that we can remember things better if those memories are formed at a time when there is a strong emotional impact – times when we are frightened, angry or falling in love," he said. "That's called emotional-memory formation. The amygdala is the part of the brain that is responsible for formation of emotional memory."

Keyword: Genes & Behavior; Emotions
Link ID: 7956 - Posted: 06.24.2010

COLUMBUS, Ohio – Scientists have learned how a genetic variation long suspected in making some people susceptible to alcoholism and narcotic drug addiction actually does so. In laboratory studies, this variation greatly reduced the amount of protein that the DNA in a cell produced. It's the difference in protein expression that may make receptors on certain brain cells much more vulnerable to the effects of addictive drugs, said Wolfgang Sadee, the study's lead author, professor and chair of pharmacology and director of the pharmacogenomics program at Ohio State University. These particular receptors, called mu opioid receptors, serve as a molecular docking station for narcotic drugs and alcohol. Until now it wasn't clear exactly what about this genetic variation, called A118G, would increase a person's chances of developing a drug addiction. (A118G is a variation in what researchers call the mu opioid receptor gene.) While Sadee and his team didn't look at the interaction between narcotics and the mu opioid receptor, they suspect that differences in protein production may leave brain cells with these receptors more open to the effects of drugs. “The real significance of this work is that one day, we may be able to tailor treatments for addiction based on how a person's genes behave,” said Sadee, who is also chair of pharmacology at Ohio State. The study appears in the current issue of the Journal of Biological Chemistry.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 7955 - Posted: 06.24.2010

For decades paleontologists have assumed that early primates rested by day and fed by night. But a new study of light-sensing proteins suggests that the first primates' eyes were better suited for daytime and that only later did some shift their activities to the night. If that's the case, then primates have always been adapted to looking for food and shelter during the day and didn't have to develop this capability as they diversified. Modern primates can be either diurnal or nocturnal, but the most primitive ones--such as bushbabies--are night owls. They have a special lining behind their retina for concentrating light, which is useful for night foraging. Some species that are active in the day also have this lining, suggesting that ancestral primates were night-dwellers, with some primates later evolving daytime routines. Wen-Hsuing Li, a molecular evolutionary biologist at the University of Chicago, and colleagues examined the molecular evidence for this scenario. They compared the DNA sequence of genes for light-sensitive proteins--called opsins--from species widely distributed on the primate tree. For one analysis, they looked at DNA from 25 species, concentrating on the genes for pigments sensitive to green or red wavelengths, which are not useful at night. If ancestral primates were nocturnal, then these genes should vary among living species, because mutations wouldn't have compromised survival. They found the opposite: The red and green pigment genes were quite similar across species. © 2005 by the American Association for the Advancement of Science.

Keyword: Evolution; Vision
Link ID: 7954 - Posted: 06.24.2010

Loss of body mass over time appears to be strongly linked to older adults’ risk of developing Alzheimer’s disease (AD), and the greater the loss the greater the chance of a person developing the disease, new research has found. The findings are the first to associate decline in body mass index (BMI) with the eventual onset of AD. The researchers suggest that the loss of body mass reflects disease processes and that change in BMI might be a clinical predictor of the development of AD. The research, reported in the September 27, 2005, issue of Neurology, was conducted by Aron S. Buchman, M.D., David A. Bennett, M.D., and colleagues at Rush University Medical Center in Chicago, IL, as part of the Religious Orders Study. The Religious Orders Study is a comprehensive, long-term look at aging and AD among Catholic nuns, priests, and brothers nationwide that has been funded by the National Institute on Aging (NIA), a component of the National Institutes of Health, U.S. Department of Health and Human Services, since 1993. Rush University Medical Center is one of more than 30 Alzheimer’s Disease Centers supported by the NIA. “People with Alzheimer’s disease are known to lose weight and body mass after they have the disease,” says Dallas W. Anderson, Ph.D., program director for population studies in the Dementias of Aging Branch of NIA’s Neuroscience and Neuropsychology of Aging Program. “This study is significant in that it looks at body mass changes in the years preceding dementia and cognitive decline. Other studies have looked at BMI at only one point in time or studied body mass loss in people who already have AD.”

Keyword: Alzheimers
Link ID: 7953 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Zoo animals often seem to ignore the presence of human visitors, but new research suggests that is not always the case for captive gorillas, which repeatedly become agitated and anxious when large numbers of people approach their exhibit. The research, published in the current journal Applied Animal Behavior Science, is the first analysis on the influence of visitors on the behavior and welfare of zoo-housed gorillas. "We noticed more behaviors suggestive of relaxation, such as increased resting, during low visitor density, and more behaviors suggestive of agitation, such as repetitive rocking, group-directed aggression and self-grooming during high visitor density," said the study's author, Deborah L. Wells. Wells, a senior lecturer in the School of Psychology at Queen's University Belfast, Ireland, explained to Discovery News that she studied six western lowland gorillas housed together at Belfast Zoological Gardens in Northern Ireland. The gorilla group includes both wild-born and captive-born males and females of different ages. The gorillas were observed for four hours a day on 20 busy days, when the average number of visitors was around 1,288. The gorillas also were observed on 20 quiet days, usually on weekdays when an average of six people visited the zoo. © 2005 Discovery Communications Inc.

Keyword: Stress; Animal Rights
Link ID: 7952 - Posted: 06.24.2010

In a significant advance toward understanding a perplexing and painful neurological disorder, an international team of researchers has discovered gene mutations associated with an inherited chronic pain and weakness syndrome known as hereditary neuralgic amyotrophy (also called HNA). No treatment is known for this disabling condition, which short-circuits a peripheral nerve center called the brachial plexus, a network of over 100,000 nerves, that branches from the spinal cord to supply muscular function and sensation to the shoulders, arms, and hands. HNA may first appear in the childhood or teen years, and lead to recurring episodes of severe, sudden onset pain in the arms and shoulders as well as weakness, loss of sensation, and muscle wasting. Episodes are often triggered by an infection, an immunization, childbirth, or overworking the arms and shoulders. Nerve inflammation and changes in the blood suggest that problems with the person's immune response are contributing to the episode. The on again/off again course of the condition, and the environmental triggers, are unusual among inherited nerve disorders. An associated aspect of the disorder in some individuals is facial features -- a long, slender face and narrow, close-set eyes slanting upward -- reminiscent of portraits by the early 20th-century Italian painter Modigliani, according to Phillip F. Chance, MD, professor of pediatrics and neurology at the University of Washington in Seattle, whose laboratory first located the gene for this disorder to chromosome 17 in 1996.

Keyword: Pain & Touch; Genes & Behavior
Link ID: 7951 - Posted: 09.27.2005