Roxanne Khamsi Some mammals are able to smell under water, a new study reveals. High speed video footage shows that the star-nosed mole and the water shrew sniff through water by quickly re-inhaling the air bubbles that leave their nostrils. Based on these counter-intuitive findings, researchers speculate that other semi-aquatic mammals might also have the capacity to pick up on underwater scents. Biologist Kenneth Catania of Vanderbilt University in Nashville, Tennessee, US, says he became intrigued when he observed star-nosed moles (Candylura cristata) blowing lots of bubbles while they swam. Curious, he measured the rate at which the animals push air out of and back into their nostrils while under water. They manages to blow and sniff roughly five to 10 times per second – about the same rate that rats inhale and exhale while actively sniffing an odour. Take a look at one of the surprising, slow-motion videos, here (mp4 format). Catania placed various objects at the bottom of a water tank, including pieces of earthworm and fish. Using a high-speed video camera, he found that the moles blew lots of bubbles that hit these targets when they neared them. Some of the odour molecules from the objects enter the bubble, and reaches the animal’s nose when it re-inhales the air, Catania explains: “This type of diffusion happens very quickly.” © Copyright Reed Business Information Ltd

Keyword: Chemical Senses (Smell & Taste)
Link ID: 9771 - Posted: 06.24.2010

In a discovery that has stunned even those behind it, scientists at a Toronto hospital say they have proof the body's nervous system helps trigger diabetes, opening the door to a potential near-cure of the disease that affects millions of Canadians. Diabetic mice became healthy virtually overnight after researchers injected a substance to counteract the effect of malfunctioning pain neurons in the pancreas. "I couldn't believe it," said Dr. Michael Salter, a pain expert at the Hospital for Sick Children and one of the scientists. "Mice with diabetes suddenly didn't have diabetes any more." The researchers caution they have yet to confirm their findings in people, but say they expect results from human studies within a year or so. Any treatment that may emerge to help at least some patients would likely be years away from hitting the market. But the excitement of the team from Sick Kids, whose work is being published today in the journal Cell, is almost palpable. "I've never seen anything like it," said Dr. Hans Michael Dosch, an immunologist at the hospital and a leader of the studies. "In my career, this is unique." Their conclusions upset conventional wisdom that Type 1 diabetes, the most serious form of the illness that typically first appears in childhood, was solely caused by auto-immune responses -- the body's immune system turning on itself. © 2006 CanWest Interactive

Keyword: Obesity
Link ID: 9770 - Posted: 06.24.2010

Certain mental exercises can offset some of the expected decline in older adults' thinking skills and show promise for maintaining cognitive abilities needed to do everyday tasks such as shopping, making meals and handling finances, according to a new study. The research, funded by the National Institutes of Health (NIH) and published in the Dec. 20, 2006, Journal of the American Medical Association, showed that some of the benefits of short-term cognitive training persisted for as long as five years. The Advanced Cognitive Training for Independent and Vital Elderly, or ACTIVE, Study is the first randomized, controlled trial to demonstrate long-lasting, positive effects of brief cognitive training in older adults. However, testing indicated that the training did not improve the participants’ ability to tackle everyday tasks, and more research is needed to translate the findings from the laboratory into interventions that prove effective at home. The ACTIVE trial was funded by the National Institute on Aging (NIA) and the National Institute of Nursing Research (NINR), both components of NIH. Sherry L. Willis, Ph.D., of Pennsylvania State University in State College, Pa., and co-authors report the findings on behalf of ACTIVE investigators at the study’s six sites: Hebrew SeniorLife, Boston; Indiana University School of Medicine, Indianapolis; Johns Hopkins University, Baltimore; Pennsylvania State University; University of Alabama at Birmingham; and University of Florida, Gainesville (in collaboration with Wayne State University, Detroit), and the data coordinating center at the New England Research Institutes, Watertown, Mass.

Keyword: Alzheimers
Link ID: 9769 - Posted: 06.24.2010

By SALLY SATEL, M.D. “Why do I use drugs?” I am asked every few weeks by a patient in our methadone clinic. I take the query as a good sign; curiosity about oneself is usually healthy. But the premise behind the question — that a person can reliably identify the psychic roots of an addiction, or any other act of self-sabotage — is highly overrated. Research psychologists have known for decades that it is very difficult to determine causation in mental life and thus, of behavior. For one thing, we can never perform an experiment. Take my patient Karen, 50, who spent most of the 1990s smoking crack. She is certain that the decade-long binge would never have happened had her mother not died when she was 12. We will never know if she is right because we cannot rewind Karen’s life, play it again, and see what would have happened if her mother had lived. Reconstructing the story of one’s life is a complicated business for other reasons. What scientists call hindsight bias kicks in when we try to figure out the causal chain of events leading to the current situation. We may well come up with a tidy story but, inevitably, it will contain large swaths of revisionist history. It’s not that we bias ourselves deliberately; it happens because the mind tends to make events in the past appear comprehensible and orderly. We forget the uncertainties that might have beset us as we struggled in real time. Narratives are shaped also by a natural tendency to focus on information that confirms theories we already hold. These theories — for example, that molested children are likely to grow up to have sexual compulsions of their own — may be imbibed from the media, self-help books or therapists. Copyright 2006 The New York Times Company

Keyword: Drug Abuse; Depression
Link ID: 9768 - Posted: 06.24.2010

By Francesca Lunzer Kritz When I get a particularly nasty headache, I race for the ibuprofen bottle and down three 200-milligram tablets (a dose long ago approved by my doctor) and get on with whatever I was doing, comforted by the knowledge that I've taken action to dull the pain and that I will feel better soon. When my husband has a headache, he delays doing anything -- including telling me, for whatever comfort that might bring -- and succumbs to the ibuprofen (taking just two tablets) only when the pain is so severe he can't do much else. Some might say our headache techniques are a manifestation of our quirky personalities -- and there may be some truth in that. But research presented at a University of Maryland Dental School conference this fall suggests my XX and my husband's XY chromosomes might also be partly to blame. While sex differences alone may not account for the variability of individual pain response, said keynote speaker Karen Berkley, a professor of neuroscience at Florida State University, growing research suggests that men's and women's nervous systems process pain information differently and act on it differently. "Sex matters in pain, and a better understanding of this is going to lead to less pain in the world," Berkley said. That could be because it might help clinicians fine-tune pain treatments as need grows. A new report by the National Center for Health Statistics (NCHS) shows that, as the U.S. population ages, patient complaints of pain and use of painkillers are rising, particularly in white women older than 45. Researchers are still trying to learn how much of the rise is sex-related and how much is tied instead to such factors as age, personality and overall health. © 2006 The Washington Post Company

Keyword: Pain & Touch; Sexual Behavior
Link ID: 9767 - Posted: 06.24.2010

By Daniel Strueber, Monika Lueck and Gerhard Roth On September 13, 2006, Kimveer Gill walked into the cafeteria at Dawson College in Montreal and, without apparent motive, shot 21 people, injuring 19 and killing two, including himself. The same day a judge in West ­Virginia sent a woman to jail for, among other atrocities, forcing her six children and stepchildren to gorge themselves on food and then eat their own vomit. Also on the 13th, a court in New York sentenced a man for killing his girlfriend by setting her on fire--in front of her 10-year-old son. There was nothing special about that Wednesday. From around the world we hear reports of murder, manslaughter, cruelty and abuse every day. Violence is ubiquitous. But what drives one person to kill, maim or abuse another, sometimes for little or no obvious reason--and why do so many violent offenders return to crime after serving time in prison? Are these individuals incapable of any other behavior? We have evaluated the results of studies conducted around the world, focusing on acts ranging from fistfights to murder, in search of the psychobiological roots of violence. Our key conclusion is simple: violent behavior never erupts from a single cause. Rather it results from a combination of risk factors--among them inherited tendencies, a traumatic childhood and other negative experiences--that interact and aggravate one another. This realization has a silver lining: positive influences may be able to offset some of those factors that promote violence, possibly offering hope for prevention. In 1972 an international team of psychologists launched one of the largest longitudinal studies ever conducted. © 1996-2006 Scientific American, Inc.

Keyword: Aggression; Genes & Behavior
Link ID: 9766 - Posted: 06.24.2010

By DENISE GRADY OPERATING ROOM 14, Dec. 12, 9:30 a.m. — “I always prep my own patients,” Dr. David J. Langer said. “It relaxes me.” He picked up a sponge soaked in antiseptic and began scrubbing the shaved skull of Chris Ratuszny, 26, a mechanic from Lindenhurst, N.Y. Mr. Ratuszny lay on the operating table, anesthetized and oblivious. His head jutted out past the end of the table, supported by four pins that had been screwed into his skull. The pins were attached, like spokes in a wheel, to a semicircular frame — surreal but standard, the hardware typically used to immobilize the head for brain surgery. A thick purple line had been drawn from his neck to the top of his head, to guide the scalpels. He was about to become the first person in the United States to undergo an operation involving the use of an excimer laser to treat a giant brain aneurysm, a dangerous ballooning of an artery that could burst and kill him or leave him with devastating brain damage. The aneurysm was too big for the most common treatments, which involve clips or metal coils; it required bypass surgery on an artery in the brain. The laser is not approved for brain surgery in the United States, but Dr. Langer got permission from the Food and Drug Administration to use it on an emergency basis for Mr. Ratuszny (ra-TOOSH-nee) last Tuesday at Roosevelt Hospital in Manhattan. Copyright 2006 The New York Times Company

Keyword: Miscellaneous
Link ID: 9765 - Posted: 06.24.2010

By Rhitu Chatterjee Does a good mood help when doing your job? Not always, a new study suggests. Happy thoughts can stimulate creativity, but for mundane work such as plowing through databases, being cranky or sad may work better. The study is the first to suggest that a positive frame of mind can have opposite effects on productivity depending on the nature of a task. Stress, anxiety, and a bad mood are notorious for narrowing people's attention and making them both think and see only what's right in front of them; for example, a person held at gunpoint usually recalls nothing but the weapon itself. Well-being, on the other hand, is known to broaden people's thinking and make them more creative. But whether a good mood also expands people's attention to visual details was unknown. To answer that question, psychologist Adam Anderson of the University of Toronto asked 24 university students to take two kinds of tests after listening to sad, happy, or neutral music. In one test, the students were asked to think of unusual words, thus testing them for the breadth of their thinking. As previously reported by various other researchers, those who has listened to the happy music--and who claimed to be in a better mood--were more successful in recalling unusual words than the other two groups. © 2006 American Association for the Advancement of Science

Keyword: Emotions; Attention
Link ID: 9764 - Posted: 06.24.2010

By Tony Fitzpatrick -- Biologists at Washington University in St. Louis have discovered a large biological clock in the smelling center of mice brains and have revealed that the sense of smell for mice is stronger at night, peaking in evening hours and waning during day light hours. A team led by Erik Herzog, Ph.D., Washington University associate professor of Biology in Arts & Sciences, discovered the clock in the olfactory bulb, the brain center that aids the mouse in detecting odors. The olfaction biological clock is hundreds of times larger than the known biological clock called the suprachiasmatic nucleus (SCN), located at the base of the brain right on top of where the optic nerves cross each other. Cells in both the SCN and the olfactory bulb keep 24-hour time and are normally highly sychronized to each other and environmental cycles of day-night. "It's been a question for some time whether the SCN functions as the only biological clock," said Herzog. "One wouldn't think that the ability to smell would cycle, but that's what we show. " I think now that the SCN is like the atomic clock, important for keeping central time, and then there are all of these peripheral clocks - for timing tasks like sleep-wake, vigilance, digestion, olfaction, hearing, touch and vision, though not all yet found. It may be that the peripheral clocks are like individual wristwatches that we must periodically reset."

Keyword: Biological Rhythms; Chemical Senses (Smell & Taste)
Link ID: 9763 - Posted: 12.19.2006

Roxanne Khamsi In addition to boosting heart health, moderate alcohol consumption might also protect against some types of arthritis, a preliminary mouse study suggests. Mice that drank diluted ethanol were about 40% less likely to develop the autoimmune disease rheumatoid arthritis than those given water instead. Researchers say that more studies are needed to understand exactly why alcohol has this effect and whether it also protects against arthritis in humans. Andrej Tarkowski at the University of Gothenburg, Sweden, and colleagues injected male mice with a type of collagen to induce rheumatoid arthritis – a disease in which the immune system starts attacking the body’s joints. Some of the animals were then given water to drink in the following weeks, while other received 10% ethanol in their drinking water. Scientists monitored the progress of the animals over the course of the following six weeks and looked for signs of joint problems and swelling. While all of the mice that drank tap water developed rheumatoid arthritis within 42 days, only 60% of those given diluted ethanol had the disease. Mice given the alcohol also had higher levels of the hormone testosterone, the researchers report. The team links this rise in testosterone to a decrease in the activity of the protein NF-Kappa-B, which is known to trigger the immune system to boost inflammation. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Neuroimmunology
Link ID: 9762 - Posted: 06.24.2010

By ALEX BERENSON Eli Lilly encouraged primary care physicians to use Zyprexa, a powerful drug for schizophrenia and bipolar disorder, in patients who did not have either condition, according to internal Lilly marketing materials. The marketing documents, given to The New York Times by a lawyer representing mentally ill patients, detail a multiyear promotional campaign that Lilly began in Orlando, Fla., in late 2000. In the campaign, called Viva Zyprexa, Lilly told its sales representatives to suggest that doctors prescribe Zyprexa to older patients with symptoms of dementia. A Lilly executive said that she could not comment on specific documents but that the company had never promoted Zyprexa for off-label uses and that it always showed the marketing materials used by its sales representatives to the Food and Drug Administration, as required by law. “We have extensive training for sales reps to assure that they provide information to the doctors that’s within the scope of the prescribing information approved by the F.D.A.,” Anne Nobles, Lilly’s vice president for corporate affairs, said in an interview yesterday. Zyprexa is not approved to treat dementia or dementia-related psychosis, and in fact carries a prominent warning from the F.D.A. that it increases the risk of death in older patients with dementia-related psychosis. Federal laws bar drug makers from promoting prescription drugs for conditions for which they have not been approved — a practice known as off-label prescription — although doctors can prescribe drugs to any patient they wish. Copyright 2006 The New York Times Company

Keyword: Schizophrenia; Alzheimers
Link ID: 9761 - Posted: 06.24.2010

By NICHOLAS WADE New recordings of electrical activity in the brain may explain a major part of its function, including how it consolidates daily memories, why it needs to dream and how it constructs models of the world to guide behavior. The recordings capture dialogue between the hippocampus, where initial memories of the day’s events are formed, and the neocortex, the sheet of neurons on the outer surface of the brain that mediates conscious thought and contains long-term memories. Such a dialogue had been thought to exist, but no one had been able to eavesdrop on it successfully. The new insight has emerged from recordings of rat brains but is likely to occur in much the same way in the human brain, which has analogous structures and the same basic principles of operation. The finding, reported on the Web site of the journal Nature Neuroscience by Daoyun Ji and Matthew A. Wilson, researchers at the Massachusetts Institute of Technology, showed that during nondreaming sleep, the neurons of both the hippocampus and the neocortex replayed memories — in repeated simultaneous bursts of electrical activity — of a task the rat learned the previous day. Copyright 2006 The New York Times Company

Keyword: Learning & Memory; Sleep
Link ID: 9760 - Posted: 06.24.2010

The findings, published today (18 December 2006) in the online edition of the journal Brain [1], used sophisticated scanning technology and computer software to measure how brain volume, form and function changed over six to seven weeks of abstinence from alcohol in 15 alcohol dependent patients (ten men, five women). The researchers from Germany, the UK, Switzerland and Italy measured the patients’ brain volume at the beginning of the study and again after about 38 days of sobriety, and they found that it had increased by an average of nearly two per cent during this time. In addition, levels of two chemicals, which are indicators for how well the brain’s nerve cells and nerve sheaths are constituted, rose significantly. The increase of the nerve cell marker correlated with the patients performing better in a test of attention and concentration. Only one patient seemed to continue to lose some brain volume, and this was also the patient who had been an alcoholic for the longest time. The leader of the research, Dr Andreas Bartsch from the University of Wuerzburg, Germany, said: "The core message from this study is that, for alcoholics, abstinence pays off and enables the brain to regain some substance and to perform better. However, our research also provides evidence that the longer you drink excessively, the more you risk losing this capacity for regeneration. Therefore, alcoholics must not put off the time when they decide to seek help and stop drinking; the sooner they do it, the better."

Keyword: Drug Abuse; Brain imaging
Link ID: 9759 - Posted: 06.24.2010

Linda Geddes Humans can follow scent trails across a field in the same way that dogs can – and they improve with practice – a intriguing new field study has revealed. Jess Porter and Noam Sobel at the University of California in Berkeley, US, and colleagues tested whether 32 people were able to follow a 10-metre-long scent trail of chocolate essence through open grass using only their noses. Two-thirds of them could. They then trained four of the subjects three times a day for three days over a two week period to see whether they improved with practice. After training the subjects followed the trail more accurately and at more than double the speed. Watch a human sniffer dog in action (2.1MB, requires QuickTime player). “Once people realised that they could do this, they seemed to develop a good sense of how to zig-zag their noses back and forth across the odour plume in order to pick up the scent most effectively,” says Porter. The findings also shed new insight into how mammals smell. Sensory biologists have long-argued about whether mammals compare the scent inputs coming into each nostril in order to localise where a smell is coming from, in the same way they use their left and right ears. © Copyright Reed Business Information Ltd.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 9758 - Posted: 06.24.2010

By DONALD G. McNEIL Jr. ASTANA, Kazakhstan — Valentina Sivryukova knew her public service messages were hitting the mark when she heard how one Kazakh schoolboy called another stupid. “What are you,” he sneered, “iodine-deficient or something?” Ms. Sivryukova, president of the national confederation of Kazakh charities, was delighted. It meant that the years spent trying to raise public awareness that iodized salt prevents brain damage in infants were working. If the campaign bore fruit, Kazakhstan’s national I.Q. would be safeguarded. In fact, Kazakhstan has become an example of how even a vast and still-developing nation like this Central Asian country can achieve a remarkable public health success. In 1999, only 29 percent of its households were using iodized salt. Now, 94 percent are. Next year, the United Nations is expected to certify it officially free of iodine deficiency disorders. That turnabout was not easy. The Kazakh campaign had to overcome widespread suspicion of iodization, common in many places, even though putting iodine in salt, public health experts say, may be the simplest and most cost-effective health measure in the world. Each ton of salt needs about two ounces of potassium iodate, which costs about $1.15. Copyright 2006 The New York Times Company

Keyword: Hormones & Behavior; Intelligence
Link ID: 9757 - Posted: 06.24.2010

Bruce Bower People with generally positive outlooks show greater resistance to developing colds than do individuals who rarely revel in upbeat feelings, a new investigation finds. Frequently basking in positive emotions defends against colds regardless of how often one experiences negative emotions, say psychologist Sheldon Cohen of Carnegie Mellon University in Pittsburgh and his colleagues. They suspect that positive emotions stimulate symptom-fighting substances. "We need to take more seriously the possibility that a positive emotional style is a major player in disease risk," Cohen says. In a study published in 2003, his group exposed 334 healthy adults to one of two rhinoviruses via nasal drops. Those who displayed generally positive outlooks, including feelings of liveliness, cheerfulness, and being at ease, were least likely to develop cold symptoms. Unlike the negatively inclined participants, they reported fewer cold symptoms than were detected in medical exams. The new study, which appears in the November/December Psychosomatic Medicine, replicates those results and rules out the possibility that psychological traits related to a positive emotional style, rather than the emotions themselves, guard against cold symptoms. Those traits include high self-esteem, extroversion, optimism, and a feeling of mastery over one's life. ©2006 Science Service.

Keyword: Neuroimmunology
Link ID: 9756 - Posted: 06.24.2010

Roxanne Khamsi The massive surge in the maternal hormone oxytocin that occurs during delivery might help protect newborns against brain damage, a new study in rats suggests. Researchers say the findings should encourage scientists to investigate whether elective caesarean sections, which lack this oxytocin surge, disrupt normal brain development. Yehezkel Ben-Ari, a neuroscientist at the Mediterranean Institute of Neurobiology in Marseille, France, and colleagues compared brain tissue samples from rat pups born naturally or by caesarean section. Brain cells from the naturally born pups did not fire in response to the nerve signalling chemical GABA, the researchers found. By comparison, at least 50% of the sampled cells from rats delivered by caesareans responded to the GABA signals. When the team gave pregnant rats atosiban – a drug that specifically blocks oxytocin’s effects – the brain cells from these rats were easily excited by GABA. This revealed that oxytocin was the hormone that made neurons from naturally delivered pups less receptive to GABA. © Copyright Reed Business Information Ltd.

Keyword: Hormones & Behavior; Development of the Brain
Link ID: 9755 - Posted: 06.24.2010

Alison Motluk and Linda Geddes Centre for Diabetes and Metabolic Medicine at Barts and The London One of the root causes of type 1 diabetes may need rethinking – the condition may be triggered by faulty nerves in the pancreas, a new study reveals. Type 1 diabetes has long been described as an autoimmune disease in which the body’s immune system targets islet cells in the pancreas, eventually destroying their ability to produce insulin. Without insulin, the body cannot convert glucose into energy, so people with type 1 diabetes have to regularly inject themselves with insulin to survive. However, what initiates the original attack on the pancreas had been unclear. It now seems that the nervous system may play a key role, according to researchers in Toronto, Canada. The team eliminated the disease in diabetes-prone mice by knocking out a set of faulty sensory nerves. They believe the finding could chart a new path in treatment of the disease in humans. Michael Dosch at the Hospital for Sick Children in Toronto, and colleagues, had previously shown that not only islet cells, but the nerve tissue around them was affected as diabetes set in. For this reason, they suspected that certain sensory nerves of the pancreas might be involved. These nerves release a neuropeptide called "substance P" and are usually responsible for ensuring that islet cells produce the right amount of insulin. © Copyright Reed Business Information Ltd.

Keyword: Obesity
Link ID: 9754 - Posted: 06.24.2010

Emma Marris Many readers of The Guardian, a British newspaper, will have been surprised at a recent online article in which Sophie Petit-Zeman, a neuroscientist and journalist, explained how she could at the same time be a vivisectionist and a vegetarian1. But they will not all have been surprised in the same way. Some will have been surprised at the existence of such a complex position in an area where much of the discussion is depressingly black and white. Others will have been surprised not by the position itself, but by its being discussed in public. As a poll of Nature readers working in the biomedical sciences reveals, many scientists who work on animals have complex takes on the issue. But they are not often willing, or encouraged, to express these feelings. Some of this is directly due to fear of animal-rights extremists; some is an indirect effect of the polarized atmosphere that surrounds the issue. In some labs, at least, scientists feel pressured to keep quiet about the grey areas of debate, lest they undermine the official mantra And how do they square the ethics of it all? As well as polling our biomedical readers (for full results see http://www.nature.com/news/specials/animalresearch), Nature set out to get some voices from the front lines — and found a lot of ducked heads. It would be fair to say that the average researcher prefers not to talk to the press about his or her work. And yet, there are those who are not only willing to talk, but have plenty to say. It quickly becomes clear that each researcher has his or her own system of ethical equations in place, but that the simplified pro–con debate makes it very difficult to communicate this — or have any kind of calm conversation about animal research. ©2006 Nature Publishing Group

Keyword: Animal Rights
Link ID: 9753 - Posted: 06.24.2010

Tom Simonite A handheld device sensitive to changes in colour not detectable by the human eye could be used to spot objects hidden by camouflage or foliage. The Image Replication Imaging Spectrometer (IRIS) system was developed by Andrew Harvey and colleagues at Heriot-Watt University in the UK. The cells in the human retina that detect coloured light are sensitive to only certain parts of the spectrum – red, green or blue. All perceived colours are a mixture of this basic palette of colours. Digital cameras work in a similar way, also using separate red, green and blue filters or sensors. By contrast, the IRIS system has a greater basic palette, of 32 or more "colours" – bands of the light spectrum. It works by dividing an image into 32 separate snapshots, each containing only the light from one of its 32 spectral bands. This allows it to pick out features that blend into one for a human observer. "In a single snapshot we can capture subtle differences in colour that the eye can't," Harvey told New Scientist. The 32 snapshots are projected onto a detector side by side, allowing the device to analyse them all simultaneously. "Until now this kind of imaging was achieved by looking at the different spectral bands sequentially in time," says Harvey, "this method is much faster." What IRIS sees can be translated into false colour images to allow a human to make use of its abilities. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 9752 - Posted: 06.24.2010