By HENRY FOUNTAIN Homing pigeons are renowned for their ability to navigate over long distances, and after decades of study scientists are pretty sure they know how the birds do it. They use their sense of smell to figure out where they are and the position of the sun to determine the direction they must fly. But less is known about how pigeons navigate when they are close to home, in more familiar surroundings. Many researchers have thought that in such situations the birds must rely, at least partly, on visual cues. "There's been controversy about whether familiar landmarks have been used," said Jessica Meade, a doctoral student in the Animal Behavior Research Group at the University of Oxford in England. "Because there was no tracking of the birds along the homeward route, the hypotheses aren't very clear." Ms. Meade and two colleagues, Dr. Dora Biro and Dr. Tim Guilford, set out to rectify that situation, using small Global Positioning System loggers attached to the backs of 15 homing pigeons. These devices, which weigh about an ounce, use satellite signals to record precise location fixes every second. The researchers released the birds about three miles from home, and each bird had about 20 flights from the same point. The results are published in Proceedings B, a journal of the Royal Society. Copyright 2005 The New York Times Company

Keyword: Animal Migration
Link ID: 6713 - Posted: 01.18.2005

By KEITH HUMPHREYS and SALLY SATEL How should we set priorities in medical research? Officials at the National Institutes of Health will grapple with this question as they allocate billions of dollars from the agency's budget this year. Two geneticists, Dr. Kathleen Merikangas of the National Institute of Mental Health and Dr. Neil Risch of Stanford University, have taken on this challenge by introducing an intriguing framework for setting priorities for genetic research. The best candidates for genetic research, they believe, are disorders whose emergence and course cannot be derailed by changes in personal habits or manipulation of the environment. Examples are autism, Type 1 diabetes and Alzheimer's disease. In contrast, lower priority on the genetic research hierarchy should go to conditions like Type 2 diabetes or alcohol or nicotine addiction, they argue. Type 2 diabetes, after all, can be largely avoided through exercise and weight loss, and teenagers will buy less beer if taxes on alcohol are high enough. Similarly, a combination of smoking bans, social pressure and taxes have had an impact on smoking. Not surprisingly, the geneticists' proposal, published in Science, drew fire from their colleagues who study addiction, including Dr. Nora Volkow, director of the National Institute on Drug Abuse. In a published rebuttal last June, they insisted that addiction deserved a much higher ranking for genetic-research money, noting that the health and social costs of alcohol and drug addiction exceed $500 billion a year. Copyright 2005 The New York Times Company

Keyword: Genes & Behavior; Drug Abuse
Link ID: 6712 - Posted: 01.18.2005

Carl T. Hall, Chronicle Science Writer Dr. Richard Olney, a San Francisco neurologist and pioneer in ALS research, has launched an ambitious clinical trial testing whether two established drugs used in AIDS and cancer might also help some ALS patients. It's a trial that Olney designed and expected to lead as head of a specialized clinic at UCSF for people with ALS, or amyotrophic lateral sclerosis, popularly known as Lou Gehrig's disease. Those plans have changed. For this trial, Olney is participating not as a doctor, but as one of 60 patients. In fact, he made it a point to be the first one to sign up. He went through the initial round of evaluations last week. He expects to be given either the AIDS drug, a protease inhibitor called ritonavir; or the cancer drug, hydroxyurea; or a placebo, starting in about two weeks. Olney, 56, is regarded to be among the country's top clinical investigators of ALS, having spent most of his career conducting trials and working with patients. In June, he was diagnosed with the same disease he has spent a lifetime studying. It's a twist of fate that has shocked the close-knit ALS world. The case also underscores the challenges posed by one of the deadliest -- and fastest- moving -- disorders of the nervous system. ©2005 San Francisco Chronicle

Keyword: ALS-Lou Gehrig's Disease
Link ID: 6711 - Posted: 06.24.2010

INDIANAPOLIS – A mutation in a recently discovered Parkinson's disease gene is believed to be the most common genetic cause of inherited forms of the disease, according to a Parkinson Study Group study appearing in The Lancet in January. Researchers say the mutation on the LRRK2 gene is responsible for 5 percent of inherited Parkinson's disease cases. Tatiana Foroud, Ph.D., associate professor of medical and molecular genetics at Indiana University School of Medicine and principal investigator on the multi-site study, said the discovery has a broad implication for genetic screening for the disease. "Our results suggest that the mutation we have studied is the most common cause of Parkinson's disease identified to date," said Dr. Foroud. "While a great deal of work remains to be done, it is clear that any future genetic testing for Parkinson's disease must include studies of the LRRK2 gene." The patients in the Indiana University study who had the mutation had longer disease duration but less severe symptoms when they were participating in the trial. That suggests that the mutation may be associated with slower disease progression, said Dr. Foroud.

Keyword: Parkinsons; Genes & Behavior
Link ID: 6710 - Posted: 06.24.2010

Mothers who are more mature tend to display more affection towards their infants whereas teenage mothers often focus on instrumental behaviour – fixing their infant’s clothes or their soother – finds a new study of maternal behaviour. “While the study is still preliminary, this finding was very surprising,” says Katherine Krpan, lead author of the study, conducted as part of her undergraduate thesis at U of T at Mississauga (UTM). She is currently a PhD student in psychology at U of T. “We expected to see teen mothers exhibit more inappropriate behaviours towards their babies such as poking and prodding, which has been shown by previous research. Instead, they were behaving appropriately but displayed more instrumental behaviour and less affection compared to the adult moms.” Krpan, along with her co-authors Alison Fleming, Rosemarie Coombs and Dawn Zinga from UTM and Meir Steiner from McMaster University and St. Joseph’s Healthcare, examined the maternal behaviour of 119 mothers in three age groups – teenage mothers (15 to 18 years), young mothers (19 to 25 years) and mature mothers (26 to 40 years), all of whom had given birth within a three-month time span. They were drawn from the Hamilton area at either hospitals or institutions that provide post-natal care. The researchers also analyzed how the mothers’ maternal responses related to their hormonal levels and early childhood experiences. All contents copyright ©2004, University of Toronto.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 6709 - Posted: 06.24.2010

The first biological test for attention-deficit hyperactivity disorder has been developed. The researchers claim the diagnosis, based on examination of eye movements, is more than 93% accurate and could lead to earlier identification and treatment for children with the condition. Scientists analysed the eye movements of 65 children aged between four and six in Thessaloniki, Greece. About half of the children had been diagnosed as having ADHD through the standard method of psychological assessment and the use of questionnaires. The children were placed in front of a computer screen while wearing special goggles to monitor their eye movements and asked to use their eyes to "lock-on to" and follow spots of light that traversed the screen during a 10-minute test. "Children with ADHD show large difference in eye movements compared with normal children. For example, those without ADHD could follow the light spot for 30 seconds to as much as five minutes, whereas the children with the disorder could only follow the stimulus for about three to five seconds," says Giorgos Pavlidis at University of Brunel, UK, who led the study. The group analysed eye movements according to various criteria, these included fixation on the stimulus, saccades - jerking between two focal points - and smooth pursuit. The computer was able to correctly diagnose 93.1% of the children. © Copyright Reed Business Information Ltd.

Keyword: ADHD
Link ID: 6708 - Posted: 06.24.2010

By Susan Kinzie, Washington Post Staff Writer A cluster of sudden deaths over a few months last winter and spring, including two suicides, prompted a George Washington University commission to ask some tough questions in an internal report that has already changed life on campus. The university doubled the student health service psychiatry hours to 20 a week. It launched a peer education program, in which students can earn credits for talking about warning signs. It pushed harder to promote counseling, with ads and online links, and encouraged faculty and staff to watch for signs of trouble. The commission also asked the university for more funding for the counseling center, and the university is seeking money from private sources for other projects. The university does not provide long-term psychiatric care on campus, and some have complained that there are not enough counseling staff members for the 20,000 or so students. Then in September, another student killed herself. © 2005 The Washington Post Company

Keyword: Depression; Stress
Link ID: 6707 - Posted: 06.24.2010

St. Paul, Minn. – Corticosteroids can be beneficial in the treatment of Duchenne muscular dystrophy and can be offered as a treatment option, according to the American Academy of Neurology and the Child Neurology Society in a new practice guideline published in the January 11 issue of Neurology, the scientific journal of the American Academy of Neurology. Duchenne muscular dystrophy is a genetic disorder linked to the X-chromosome. It is the most common form of muscular dystrophy in children and occurs when the protein dystrophin is missing. This causes a gradual breakdown of muscles and a decline in muscle strength. Duchenne muscular dystrophy mainly affects boys. An estimated one in 3,500 males worldwide has the disorder, and each year approximately 400 boys in the United States are born with it. Symptoms usually appear between ages two and five and include frequent falls, large calf muscles, and difficulty running, jumping, and getting up. There is no cure. The guideline authors reviewed all available research for the use of corticosteroids in the treatment of Duchenne muscular dystrophy. Corticosteroids are man-made drugs that are similar to the body’s hormone cortisone. Two corticosteroids, prednisone and deflazacort, were found to slow the rate of muscle deterioration, and are recommended as potential treatments to minimize the effect of Duchenne muscular dystrophy.

Keyword: Muscles; Movement Disorders
Link ID: 6706 - Posted: 06.24.2010

A Colorado man who went to the dentist complaining of toothache found he had a 4-inch (10cm) nail in his skull. Patrick Lawler had been suffering pain and blurry vision since a nailgun backfired on him at work, AP news agency reported. The machine sent a nail through a nearby piece of wood - but little did Mr Lawler realise another nail had shot into the roof of his mouth. The nail was embedded 4cm into his brain - barely missing his right eye. Six days after his 6 January work accident, Mr Lawler decided to visit the dental clinic where his wife Katerina works because painkillers and ice failed to stop the pain. "We all are friends, so I thought the [dentists] were joking... then the doctor came out and said, 'There's really a nail,'" Mrs Lawler said, according to AP. "Patrick just broke down. I mean, he had been eating ice cream to helpthe swelling." Mr Lawler remains in hospital following a four-hour operation to remove the nail. (C)BBC

Keyword: Brain Injury/Concussion
Link ID: 6705 - Posted: 01.17.2005

Abnormal hormone levels could play a significant role in how multiple sclerosis develops, research suggests. Researchers from University La Sapienza in Italy looked at hormone levels in 25 men and 35 women with MS, and in 36 people without the disease. Women with low testosterone levels were found to have more brain tissue damage. There was no difference in testosterone levels between men with or without MS. The Journal of Neurology, Neurosurgery and Psychiatry published the study. It is known that MS affects twice as many women as men, and that it is significantly less active during pregnancy, suggesting hormones do play a role in its development. MS is an inflammatory disease which causes a range of symptoms from fatigue and numbness to difficulties with movement, speech and memory. The relapsing-remitting form of the disease follows a characteristic pattern of periods of deterioration followed by partial recovery. In this study, researchers compared levels of a range of hormones in the healthy people and those with MS. The average age of the participants was 32, and those with MS had had the relapsing-remitting form of the disease for an average of six years. Women were tested during both phases of their menstrual cycle, to account for variations in hormone levels. None used oral contraceptives, and all had normal cycles. Men and women with MS were also given magnetic resonance imaging (MRI) brain scans to identify areas of tissue damage and inflammation, caused by the disease. (C)BBC

Keyword: Multiple Sclerosis; Hormones & Behavior
Link ID: 6704 - Posted: 01.17.2005

Young people with brain injuries may benefit from drugs used to treat Alzheimer's patients, research shows. The drug boosts the function of a key brain chemical called acetylcholine. Brain injury resulting from accidents and serious falls is the most common cause of disability in young people. The Cambridge University research, published in the journal Brain, suggests boosting the chemical acetylcholine may limit the effect of this damage. Potentially, this could help minimise the symptoms of brain injury, which can include the inability to concentrate, learn and remember. The researchers examined 31 young adults who survived a moderate-to-severe head injury. Patients underwent a number of tests and scans to determine the extent of their injuries, and the problems they were having. The results showed a reduction in key grey matter in parts of the brain associated with attention, learning and memory. Crucially, the abnormalities seemed to be linked to an imbalance of acetylcholine - a chemical which helps brain cells communicate with each other. The researchers believe that drugs called cholinesterase inhibitors, which block the breakdown of this chemical in the brain, may prove to be an effective treatment. Currently, cholinesterase inhibitors are used to treat the early symptoms of Alzheimer's disease. (C)BBC

Keyword: Brain Injury/Concussion; Alzheimers
Link ID: 6703 - Posted: 01.15.2005

By Chris Summers, BBC News As the British government unveils plans to make lie detector tests mandatory for convicted paedophiles, some scientists in the US are working on more advanced technology which might be better equipped at detecting deception. Imagine the Pentagon equipped with a machine which can read minds. Sound like the plot of a Hollywood thriller? Well, it might not be that far away. The US Department of Defense has given Dr Jennifer Vendemia a $5m grant to work on her theory that by monitoring brainwaves she can detect whether someone is lying. She claims the system has an accuracy of between 94% and 100% and is an improvement on the existing polygraph tests, which rely on heart rate and blood pressure, respiratory rate and sweatiness. Her system involves placing 128 electrodes on the face and scalp, which translate brainwaves in under a second. Subjects only have to hear interrogators' questions to give a response. But the system has a long way to go before it replaces polygraphs, which were invented almost a century ago and remain a tried and tested system of deception detection. On Thursday the UK government unveiled its Management of Offenders and Sentencing Bill. A key plank of the bill is increasing the use of polygraph tests for convicted paedophiles who have been released on licence. A voluntary scheme has been running in 10 pilot areas in England since September 2003. But under the new bill the tests will become compulsory for paedophiles in the 10 pilot areas. They are asked whether they have had contact with children, while having their anxiety levels measured. (C)BBC

Keyword: Stress
Link ID: 6702 - Posted: 01.15.2005

Researchers at New York University have developed a model of the intra-cellular mammalian biological clock that reveals how rapid interaction of molecules with DNA is necessary for producing reliable 24-hour rhythms. They also found that without the inherent randomness of molecular interactions within a cell, biological rhythms may dampen over time. These findings appeared in the most recent issue of the Proceedings of the National Academy of Sciences (PNAS). Daniel Forger, an NYU biologist and mathematician, and Charles Peskin, a professor at NYU's Courant Institute of Mathematical Sciences and Center for Neural Science, developed a mathematical model of the biological clock that replicates the hundreds of clock-related molecular reactions that occur within each mammalian cell. Biological circadian clocks time daily events with remarkable accuracy--often within a minute each day. However, understanding how circadian clocks function has proven challenging to researchers. This is partly because the 24-hour rhythm is an emergent property of a complex network of many molecular interactions within a cell. Another complication is that molecular interactions are inherently random, which raises the question how a clock with such imprecise components can keep time so precisely. One way to combat molecular noise is to have large numbers of molecular interactions, but this is limited by the small numbers of molecules of some molecular species within the cell (for instance, there are only two copies of DNA).

Keyword: Biological Rhythms
Link ID: 6701 - Posted: 01.15.2005

Diana Parsell Several hundred million people today practice the ancient custom of chewing betel. In south Asia, where the habit is most prevalent, the signs are hard to miss. Placed inside the cheek and sucked for hours, a betel wad turns saliva bright red, and betel users' spit does likewise to sidewalks and streets. People typically chew betel as a quid consisting of nut pieces from an Areca catechu palm mixed with powdered lime (calcium hydroxide) and wrapped in the leaf of the pepper plant Piper betle. Betel is used primarily as a stimulant. Areca nuts contain alkaloids that induce euphoria and raise a person's heart rate and skin temperature. Some chewers say a cheekful of betel aids digestion. Over the past decade, a variety of evidence has linked betel chewing to several types of oral cancer. Although the custom is falling out of fashion in several countries, such as Thailand and Cambodia, it's growing in popularity in other areas. Especially troubling is that many new betel users are adolescents and children, say Asian health officials. Some governments in Asia are taking steps to reduce betel use. Oral cancer is relatively rare in Western countries. In some south Asian countries, however, it ranks first among malignancies. According to the World Health Organization (WHO), a disproportionate number of the world's cases of oral cancer in men occurs in regions of Asia where betel chewing is common. Once diagnosed mainly in adults, such cancers are now on the rise in young people. Copyright ©2005 Science Service.

Keyword: Drug Abuse
Link ID: 6700 - Posted: 06.24.2010

How do you remember your own name? Is it possible ever to forget it? The memory trace, or engram, "feels" like it is stored permanently in the brain and it will never be forgotten. Indeed, the current view of memory is that, at the molecular level, new proteins are manufactured, in a process known as translation, and it is these newly synthesized proteins that subsequently stabilize the changes underlying the memory. Thus, every new memory results in a permanent representation in the brain. But Northwestern University neuroscientist Aryeh Routtenberg has presented a provocative new theory that takes issue with that view. Routtenberg, with doctoral student Jerome L. Rekart, outlined the new theory on memory storage in the January issue of the journal Trends in Neuroscience. Rather than permanent storage, there is a "dynamic, meta-stable" process, the authors said. Our subjective experience of permanence is a result of the re-duplication of memories across many different brain networks. For example, one's name is represented in innumerable neural circuits; thus, it is extremely difficult to forget. But each individual component is malleable and transient, and as no particular neural network lasts a lifetime, it is theoretically possible to forget one's own name.

Keyword: Learning & Memory
Link ID: 6699 - Posted: 01.15.2005

Volunteers are to be 'burnt' by scientists to see if faith eases pain. Oxford University scientists will carry out experiments on hundreds of people in a bid to understand how the brain works during states of consciousness. One aspect of the two-year study will involve followers of both religious and secular beliefs being burnt to see if they can handle more pain than others. Some volunteers will be shown religious symbols such as crucifixes and images of the Virgin Mary during the tests. Researchers believe the study may improve understanding of faith, how robust it is and how easily it can be dislodged. The team from the newly-formed Centre for Science of the Mind also want to include people with survival techniques in the experiments, which may help the special forces easily identify people with high pain thresholds. Volunteers will have a gel containing chilli powder or heat-pad applied to the back of their hand to simulate pain. A team of neurologists, pharmacologists and anatomists will then analyse how people react by using brain scans. Another part of the research involves tests using anaesthetic, to see what effect it has on the brain and why some people need higher doses to make them unconscious. Baroness Greenfield, director of the centre, said 20 years ago scientists had shied away from studying the brain in such away but that was now changing. "We want to find out what the brain is doing, how it is working when we are having feelings and most importantly of all when we are conscious. (C)BBC

Keyword: Pain & Touch
Link ID: 6698 - Posted: 01.14.2005

By TYLER KEPNER Major league baseball players agreed to a stricter policy for steroids and other drugs yesterday that will include more tests and tougher penalties. Baseball and union officials also announced an expanded list of banned substances, although players will not be tested for amphetamines. The announcement, made at a meeting of baseball owners in Scottsdale, Ariz., amounted to the players' union response to pressure from the government, fans and some of its own members to take a stronger stand against steroids; the players had resisted testing for any drugs, saying it was an invasion of their privacy. Baseball owners also largely ignored the topic for years. "I felt an obligation that some day, somebody could come up to you and say, 'You people knew about this, and you didn't do anything about it,' " Commissioner Bud Selig said on a conference call. "That was something I would have had a very hard time living with. But the fact of the matter is that today, we did something about it." Baseball did not adopt steroid testing for major leaguers until 2002, when it negotiated a program with the union that was roundly criticized as being too lenient. Rob Manfred, an executive vice president for baseball, said the new policy was different in the frequency of testing during the season; the addition of off-season testing; the number of banned substances; and the penalties. Copyright 2005 The New York Times Company

Keyword: Drug Abuse; Hormones & Behavior
Link ID: 6697 - Posted: 01.14.2005

Researchers have discovered that deletion of a specific gene permits the proliferation of new hair cells in the cochlea of the inner ear — a finding that offers promise for treatment of age-related hearing loss. This type of hearing loss is caused by aging, disease, certain drugs, and the cacophony of modern life. It is the most common cause of hearing loss in older people. The research team, which included Howard Hughes Medical Institute investigator David P. Corey, published their findings on January 13, 2005, in Science Express, which provides rapid electronic publication of selected Science publications. Zheng-Yi Chen, who is at Massachusetts General Hospital and Harvard Medical School, is the senior author of the article. He trained with Corey at Harvard Medical School. Other co-authors are from the University of Virginia School of Medicine, Tufts-New England Medical Center, and Northwestern University. Hair cells in the cochlea detect sound by vibrating in response to sound waves, triggering nerve impulses that travel to the auditory region of the brain. Normally, humans are born with a complement of about 50,000 hair cells. But since the cells do not regenerate, the steady rate of hair-cell loss that can accompany aging produces significant hearing loss in about a third of the population by the time they reach 70-years-old. © 2004 Howard Hughes Medical Institute.

Keyword: Hearing; Regeneration
Link ID: 6696 - Posted: 06.24.2010

Helen Pearson A group of drugs already approved for humans can prolong the lifespan of worms. So, will these medicines be sought after by those seeking eternal youth? Researchers have long been trying to find drugs or elixirs that can stave off ageing. But they have met with little success, partly because it is laborious and time-consuming to show that a drug adds years to our lives. To get around this problem, Kerry Kornfeld of Washington University in St Louis, Missouri, and his team tested drugs on a tiny, short-lived worm called Caenorhabditis elegans. Researchers have shown before that tweaking certain genes can prolong this worm's life. The team split the worms into groups and doped their food with 19 prescription medicines, from steroids to diuretics to anti-inflammatory drugs. "We went through a pharmaceutical textbook and picked a drug from each class," Kornfeld says. Most of the drugs had no effect, or even killed the worms at high doses. But an anticonvulsant used to fight epilepsy, and two other similar compounds, lengthened the animals' lives by as much as 50%. Normal signs of ageing were also delayed in the animals. ©2005 Nature Publishing Group

Keyword: Epilepsy
Link ID: 6695 - Posted: 06.24.2010

By THE ASSOCIATED PRESS Doctors in training were more than twice as likely to get in a car crash while driving home after working 24 hours or longer, compared with when they worked shorter shifts, according to a study conducted by Harvard Medical School. The study also found that after extended shifts young doctors were about six times more likely to report a near-miss accident and that they sometimes fell asleep while driving. "A lot of the lay public doesn't realize that twice a week most young doctors in this country are forced by hospitals to work these marathon shifts of 30 hours in a row," said Dr. Charles A. Czeisler, a professor of sleep medicine at Harvard Medical School and the head of sleep medicine at Brigham and Women's Hospital in Boston. "If they're going to require these trainees to work such long hours, they should at least provide them with transportation home." The study, reported in the New England Journal of Medicine, was done by some of the same Harvard Medical School researchers who reported last fall that sleep-deprived doctors made one-third more errors during their many long shifts than they did on the shorter ones. The new study included monthly surveys collected from 2,737 first-year interns around the country from April 2002 through May 2003. More than two-thirds of the drowsy doctors drove home from work. Copyright 2005 The New York Times Company

Keyword: Biological Rhythms; Sleep
Link ID: 6694 - Posted: 01.13.2005