By BARNABY J. FEDER An unexpected takeover battle between Boston Scientific and Johnson & Johnson for control of Guidant seems bound to send aftershocks through the medical device industry. There is widespread speculation about the effects on prominent competitors like Medtronic and St. Jude Medical in Guidant's main business of electrical implants that regulate heart functioning. Investors and analysts also wonder who will end up with Guidant's business of making stents and other devices used to treat circulatory illnesses. But there are less obvious industry niches that may also be affected by the outcome, like the one occupied by Cyberonics, a Houston-based company in which Boston Scientific has a 15 percent stake. The company and its stock have attracted attention as federal regulators first rejected, then reconsidered and approved Cyberonics' nerve-stimulating device as a treatment for severe depression. Nerve stimulation involves the use of devices that are similar to Guidant's pacemakers and heart defibrillators, but are attached to the brain or other parts of the nervous system to treat conditions like Parkinson's disease, epilepsy and chronic pain. Such devices constitute a $930 million market that is on its way to $2 billion in 2010, according to Lazard Capital Markets. Copyright 2005The New York Times Company

Keyword: Depression; Parkinsons
Link ID: 8289 - Posted: 12.09.2005

It's a scene football fans will see over and over during the bowl and NFL playoff seasons: a player, often the quarterback, being slammed to the ground and hitting the back of his head on the landing. Sure, it hurts, but what happens to the inside of the skull? Researchers and doctors long have relied upon crude approximations made from test dummy crashes or mathematical models that infer – rather loosely – what happens to the brain during traumatic brain injury or concussion. But the truth is that the state of the art in understanding brain deformation after impact is rather crude and uncertain because such methods don't give any true picture of what happens. Now, mechanical engineers at Washington University in St. Louis and collaborators have devised a technique on humans that for the first time shows just what the brain does when the skull accelerates.

Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 8288 - Posted: 06.24.2010

Colleges are becoming more and more like shopping malls. At least, that's what Barry Schwartz, professor of Social Theory and Social Action at Swarthmore and author of The Paradox of Choice: Why More is Less, thinks. Higher education has moved away from educating students in set civic traditions and towards giving people as many options as a J. Crew catalogue. As Schwartz writes, "In some rather prestigious institutions, this shopping-mall view has been carried to an extreme. In the first few weeks of classes, students sample the merchandise. They go to a class, stay ten minutes . . . then walk out . . . to try another class." It might seem that all these new options would ensure that students are happier than ever. Similarly, the opportunity to make more choices anywhere in life would lead to increased satisfaction with life in general. But Schwartz, and myself, would disagree. I hate shopping period. I have perfected my shopping strategy to produce as much agony as possible. First I narrow my possibilities to a mere 30 or 40. Then I hand-write a schedule (the on-line version refuses to display as many classes as I wish), fitting three to four visits in each 50 minute period. When classes finally begin I race from one to the next, my logic changing with every classroom. If I like the class, then I can leave after 15 minutes to visit another just in case there's something better at the same time. If I hate the class, I can leave after 15 minutes, but I am sure to save the syllabus just in case. And if I am unsure about the class then I leave after 15 minutes to compare it with other mediocre classes. The whole process ends with me frantically running from advisor to dean to parents to friends begging them to tell me what to do and to save me from having to make a decision myself. Copyright © 2003 Yale Review of Books

Keyword: Emotions
Link ID: 8287 - Posted: 06.24.2010

by David J. Buller In nearly every newspaper or magazine these days you can find evolutionary explanations for a variety of human behaviors — for what we seek in mates, why we are sometimes unfaithful, why we love our children (but not our stepchildren), why men and women differ, and even why husbands kill their wives. All of these explanations are offered in the name of evolutionary psychology. But what is evolutionary psychology? There are actually two different answers to this question, and it is useful to clearly distinguish them. On the one hand, many behavioral scientists define evolutionary psychology simply as “the evolutionary study of mind and behavior.”1 So conceived, evolutionary psychology is a field of inquiry, akin to mechanics, which is defined not by any specific theories about human psychology, but by the questions it investigates. And these questions cover a broad spectrum. Why do males in some hunter-gatherer populations hunt, which offers highly variable caloric returns, when they could reliably provide their families with equivalent calories by gathering? Why do women in some hunter-gatherer populations wait an average of four years between pregnancies? What evolutionary forces drove cortical expansion in humans? How and why did altruism, or language, evolve? On the other hand, several prominent and influential behavioral scientists — led on the popular front by Steven Pinker (The Blank Slate) and David Buss (The Evolution of Desire and The Murderer Next Door) and on the academic front by Leda Cosmides and John Tooby (The Adapted Mind) — define evolutionary psychology as a specific set of doctrines concerning the evolutionary history and current nature of the human mind. In this sense, evolutionary psychology as a field of inquiry has been elevated by its practitioners to an all encompassing paradigm of Evolutionary Psychology (EP).

Keyword: Evolution
Link ID: 8286 - Posted: 06.24.2010

Pacifiers aren't just for soothing colicky babies anymore. A new study has found that use of a pacifier during sleep reduced the chances of a baby suffering from sudden infant death syndrome (SIDS) by 90 percent. Furthermore, pacifiers eliminated the increased risk associated with babies who slept on their stomach or in soft bedding--factors that have been shown to increase the risk of SIDS as much as 10-fold. "A baby who sleeps on his stomach without a pacifier has a 2.5 times greater risk of SIDS," explains De-Kun Li, a reproductive epidemiologist with Kaiser Permanente in Oakland, Calif., who led the research. "If you use a pacifier, that baby's risk disappears." The work draws on interviews with 185 mothers of SIDS babies and 312 mothers of control infants collected between 1997 and 2000. Of course, this doesn't mean that babies should be allowed to sleep on their stomachs, he cautions. Campaigns to promote sleeping on the back have cut the incidence of SIDS significantly. But pacifier use showed benefits no matter the baby's age, how it slept and even if its mother smoked during or after pregnancy, according to the research, which will be published Saturday in the British Medical Journal. © 1996-2005 Scientific American, Inc

Keyword: Sleep
Link ID: 8285 - Posted: 06.24.2010

Roxanne Khamsi When faced with uncertainty, people try to make the most logical decision, given the facts available. But a brain-imaging study has found that, when tackling these tricky decisions, the brain's emotional areas also spring into action. Ming Hsu of the California Institute of Technology in Pasadena and his colleagues compared volunteers' brain activity in two betting games. As the volunteers played, the scientists watched changes in their brain activity using functional magnetic resonance imaging. In one game, researchers gave volunteers the chance to guess the colour of a card drawn from a deck containing equal numbers of red and blue cards, and to bet on whether they were right. In the other game, the ratio of red to blue cards remained unknown. Players in this game were less likely to put money on their guess. And there was a burst of activity in their brain's emotion-processing centres, the amygdala and the orbitofrontal cortex. The study is published in this week's Science1. The volunteers didn't know that the odds of them guessing right were actually the same in both games. Because players in the second game could only say 'red' or 'blue', their chances of betting correctly remained at 50%, whatever the ratio of blue and red cards. ©2005 Nature Publishing Group

Keyword: Emotions
Link ID: 8284 - Posted: 06.24.2010

Rowan Hooper THANKS to research on "mighty mice", the lives of people suffering from muscle-wasting diseases such as muscular dystrophy could be transformed. Two treatments that block a protein called myostatin, which slows muscle growth, are now in the pipeline. The first approach, announced this week, aims to use a drug to mop up myostatin. Meanwhile a second method, which is already in clinical trials in people with muscular dystrophy, uses antibodies to disable the protein. In 1997, researchers led by Se-Jin Lee of Johns Hopkins University School of Medicine in Baltimore, Maryland, engineered mice in which the gene for myostatin had been "knocked out". The animals grew muscles twice as big as normal. A defect in the myostatin gene was what caused a German toddler, whose story was widely publicised last year, to develop prodigious muscles. Now Lee has produced a soluble molecule called activin type IIB receptor (ACVR2B) that binds to myostatin in normal mice, causing their muscles to bulk up. He hopes ACVR2B can be used to treat conditions such as Duchenne muscular dystrophy, a genetic disease that affects 1 in 3000 boys. Their muscles waste away because of a defect in the gene for the protein dystrophin, which is important in organising muscle structure. © Copyright Reed Business Information Ltd

Keyword: Muscles; Movement Disorders
Link ID: 8283 - Posted: 06.24.2010

A new study from the Monell Chemical Senses Center may shed light on why some people like salt more than others. The results suggest that a person's liking for salty taste may be related to how much they weighed when they were born. In a paper published in the European Journal of Clinical Nutrition, the Monell researchers report that individual differences in salty taste acceptance by two-month old infants are inversely related to birth weight: lighter birth weight infants show greater acceptance of salt-water solutions than do babies who were heavier at birth. According to lead author Leslie Stein, Ph.D., "The early appearance of this relationship suggests that developmental events occurring in utero may have a lasting influence on an individual's preference for salty taste." A similar relationship was found in a subset of the same children at preschool age, suggesting that the relationship between salty taste preference and birth weight persists at least through early childhood, a critical time for the formation of flavor and food preferences. By studying individual differences in liking for salty taste, scientists hope to obtain needed insights into the underlying factors driving salt preference and intake. Such information could potentially be used in programs designed to reduce salt intake, which is believed by many to contribute to the development and maintenance of high blood pressure.

Keyword: Chemical Senses (Smell & Taste); Development of the Brain
Link ID: 8282 - Posted: 12.08.2005

Playing too many video games has been reported to increase violent tendencies in some people or make some kids slow learners, but they may also create skilled surgeons and have also been used as a virtual distraction helping some kids get through painful medical treatments. Now it seems that playing certain special computer games could help prepare some kids for school. Psychologists at the University of Oregon designed the games to train the network of brain areas involved in attention, which undergoes important development between ages three and seven. "It's important, particularly in child development, for the child's ability to regulate their thoughts and to control their emotions," explains neuro-psychologist Mike Posner. "This executive network, which tends to control the child's emotions, and also allows them to continue to work on a particular task, it's also likely that that network is also deficient in ADHD children." Posner and his research team were interested in seeing whether, with a certain amount of training, they might be able to improve the efficiency of the network in children at the age when the network is developing. © ScienCentral, 2000-2005.

Keyword: ADHD; Attention
Link ID: 8281 - Posted: 06.24.2010

By Susan Brown What's behind the satisfaction we get from a tasty dessert? Researchers have long assumed it has something to do with the neurotransmitter dopamine. But a new study suggests that this so-called "pleasure molecule" isn't necessary for us to enjoy that piece of cake after all. Without the pleasurable kick dopamine is thought to provide, researchers assumed that people would be less inclined to get hooked on gambling or drugs (ScienceNOW, 10 January:). But recent evidence has called this theory into question. For example, mice lacking a type of receptor for dopamine still seek out morphine, suggesting that they find the drug rewarding even without dopamine signaling. To investigate further, neurobiologists Thomas Hnasko, Bethany Sotak, and Richard Palmiter at the University of Washington in Seattle gave morphine to dopamine-deficient mice. Once the morphine wore off, the team let the animals roam freely between two chambers: one where they had received the morphine and another one. Dopamine-deficient mice given moderate to high levels of morphine favored the morphine-associated chamber, just like normal mice did, further evidence that dopamine isn't necessary to experience the rewards of morphine, the team reports 8 December in Nature. © 2005 American Association for the Advancement of Science.

Keyword: Drug Abuse
Link ID: 8280 - Posted: 06.24.2010

Roxanne Khamsi Experiments on immature rats' brains suggest that treating epileptic children with benzodiazepine drugs could do more harm than good, scientists in France have claimed. They have found that the neurotransmitters unlocked by these drugs cause changes in brain chemistry that actually promote epileptic activity. Anticonvulsant benzodiazepines are a last-ditch treatment used to stop seizures in both infants and adults. Some medical experts think that the electrical activity associated with seizures can change brain networks, making them more susceptible to future epileptic activity. So understanding the chemistry of seizures might lead to drugs that can counteract epilepsy's development, says Yehezkel Ben-Ari, a neuroscientist at the Mediterranean Institute of Neurobiology in Marseille. His team studied the electrical and chemical activity of brains removed from baby rats. They were particularly interested in the hippocampus, a part of the brain important in epileptic seizures. The researchers found that the neurotransmitter gamma-aminobutyric acid (GABA) triggers rapid electrical signalling in the immature hippocampus - a hallmark of epileptic seizures. Benzodiazepine drugs enhance the action of this neurotransmitter. ©2005 Nature Publishing Group

Keyword: Epilepsy
Link ID: 8279 - Posted: 06.24.2010

The brainier male bats are, the smaller their testicles, according to a new study. Researchers suggest the correlation exists because both organs require a lot of energy to grow and maintain, leading individual species to find the optimum balance. The analysis of 334 species of bat found that in species where the females were promiscuous, the males had evolved larger testes but had relatively small brains. In species, where the females were monogamous, the situation was reversed. Male fidelity appeared to have no influence over testes or brain size. Both brain tissue and sperm cells require a lot of metabolic energy to produce and maintain. The different species appear to have evolved a preference for developing one organ more than the other, presumably determined by which will help them produce more offspring. “An extraordinary range of testes mass was documented across bat species - from 0.12% to 8.4% of body mass. That exceeds the range of any other mammalian order,” says Scott Pitnick, from Syracuse University in New York, US, one of the research team. Primate testes vary between species from 0.02% and 0.75% of body mass. Copyright Reed Business Information Ltd.

Keyword: Evolution; Sexual Behavior
Link ID: 8278 - Posted: 06.24.2010

A brain chemical recently found to boost trust appears to work by reducing activity and weakening connections in fear-processing circuitry, a brain imaging study at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) has discovered. Scans of the hormone oxytocin’s effect on human brain function reveal that it quells the brain’s fear hub, the amygdala, and its brainstem relay stations in response to fearful stimuli. The work at NIMH and a collaborating site in Germany suggests new approaches to treating diseases thought to involve amygdala dysfunction and social fear, such as social phobia, autism, and possibly schizophrenia, report Andreas Meyer-Lindenberg, M.D., Ph.D., NIMH Genes Cognition and Psychosis Program, and colleagues, in the December 7, 2005 issue of the Journal of Neuroscience. “Studies in animals, pioneered by now NIMH director Dr. Thomas Insel, have shown that oxytocin plays a key role in complex emotional and social behaviors, such as attachment, social recognition and aggression” noted NIH Director Elias Zerhouni, M.D.. “Now, for the first time, we can literally see these same mechanisms at work in the human brain.” “The observed changes in the amygdala are exciting as they suggest that a long-acting analogue of oxytocin could have therapeutic value in disorders characterized by social avoidance,” added Insel.

Keyword: Emotions; Hormones & Behavior
Link ID: 8277 - Posted: 06.24.2010

Researchers have found evidence that may partially exonerate a protein known to be a culprit in the progression of Alzheimer's disease. Their new studies show that the protein p25, which wreaks havoc in the brains of patients with Alzheimer's disease, also has a good side in promoting the plasticity of the brain. In studies in mice, the scientists have shown that the enzyme promotes structural changes in the brain associated with learning and memory. The studies indicate that when the concentration of the protein reaches excessive levels, it contributes to the brain cell death associated with Alzheimer's disease (AD). Their discovery of the dual nature of p25 suggests that drugs that partially inhibit p25's target enzyme could protect the neurons of patients with AD. The research team, which was led by Howard Hughes Medical Institute investigator Li-Huei Tsai, reported its findings in the December 8, 2005, issue of the journal Neuron. Tsai and her colleagues at Harvard Medical School collaborated on the studies with researchers from the National Institute of Mental Health. In earlier studies, Tsai and her colleagues discovered that an enzyme called cyclin-dependent kinase 5 (Cdk5) plays a central role in AD pathology. Like other kinases, Cdk5 switches on enzymes by attaching a phosphate group to them. Under tight regulation by a protein called p35, Cdk5 controls the construction and maintenance of neuronal connections in the brain. © 2005 Howard Hughes Medical Institute.

Keyword: Alzheimers
Link ID: 8276 - Posted: 06.24.2010

By Caroline Ryan BBC News website health reporter The man who received the first cornea transplant was given no antibiotics, no drugs to stop him rejecting the tissue - and had to endure his eyelids being sewn shut for 10 days before he knew if the procedure had worked. But this was 100 years ago. That first, groundbreaking, operation took place in Olomouc, now in the east of the Czech Republic. It was carried out by Dr Eduard Zirm, an ophthalmic specialist who had been trying to achieve a successful transplant for some time. The recipient was Alois Gloger, a labourer who had been blinded in an accident while working with lime. The corneas came from an 11-year-old boy who had been blinded by deep injuries to his eyes. A few hours after the operation, the 43-year-old patient could see again. He retained his eyesight for the rest of his life and was back working on his farm within three months. Dr Zirm, in common with other specialists across the world, had long been trying to achieve a successful cornea transplant. He transplanted corneas into both the patient's eyes. To get around the lack of fine material to sew the cornea to the eye, he used strips of the conjunctiva - the lining of the white of the eye - prising up one end of a strip and using it to "tape down" the new cornea. To cut out the cornea for transplant, he used a trephine, a circular surgical instrument with a cutting edge, powered by clockwork. He then sewed the patient's eyelids shut for 10 days to allow time for the cornea and the conjunctiva strips to "knit" together. When he unstitched the eyelids, the graft in the patient's left eye had taken - although the other had failed. (C)BBC

Keyword: Vision
Link ID: 8275 - Posted: 12.07.2005

Babies born with a larger head may have an increased risk of childhood brain cancer, research suggests. Head circumference at birth reflects brain size, and researchers suspected that in some cases this might be a sign of abnormal growth patterns. A Norwegian Institute of Public Health team tested their hypothesis by examining the health records of over a million young people. They found the larger the head at birth, the greater the risk. For every centimetre increase in head circumference at birth, the relative risk of having a tumour rose by 27%. However, the overall risk was still small. Out of 1,010,366 children in the study just 453 were diagnosed with brain cancer. In the UK, about 300 children are diagnosed with a brain tumour each year. Currently, around 30% of affected children die of the disease. The researchers said their work suggested that brain cancers might begin to develop before birth. Cancer cells - and particularly those that play a key role in developing blood supply to a tumour - are thought to be stimulated by the same growth factors as healthy tissues during development. Thus if healthy tissues grow at a faster rate than usual, then maybe growth factors are present at levels that make the development of malignant tissues more likely too. Another hypothesis is that large children may be more prone to cancer simply because they have more cells. (C)BBC

Keyword: Development of the Brain
Link ID: 8274 - Posted: 12.07.2005

By Caroline E. Mayer, Washington Post Staff Writer Food and beverage companies are using television ads to entice children into eating massive amounts of unhealthful food, leading to a sharp increase in childhood obesity and diabetes, a national science advisory panel said yesterday. The Institute of Medicine, part of the National Academies, called on food and beverage manufacturers and restaurants to make more healthful products and shift their advertising emphasis to promote them. If the companies do not do so within two years, Congress should mandate changes, especially for broadcast and cable television ads, the institute said. "There is strong evidence that exposure to television advertising is associated with" obesity, the government-chartered institute said in a congressionally requested report to determine the effects of food advertising on children's health. The report said most of the food and beverage products promoted to children are high in calories, sugar, salt and fat and low in nutrients. Many are promoted with popular cartoon characters. There are, for example, SpongeBob SquarePants cereal, Pop-Tarts, cookies and candy and Scooby-Doo fruit snacks and crackers. The institute said such characters should be used to promote only products that support healthful diets. © 2005 The Washington Post Company

Keyword: Obesity; Development of the Brain
Link ID: 8273 - Posted: 06.24.2010

— When Sonia Ruschak's 5-month-old daughter, Violet, wasn't napping much, she started to feel stressed. Then the problem got worse — her daughter became even crankier and slept less. After a while, Ruschak decided to stop worrying — and suddenly things got better. "I definitely think she relaxed more and cried less when I stopped stressing," she said. While parents have long felt their children read and react to their emotional states, scientists have only recently begun quantifying that connection and considering its importance in a child's development. Their research shows that the connection between an infant and a primary caregiver is so key that there can be drawbacks to placing the child in day care very early in life. Later on, however, there may be benefits to some separation. Allan Schore, a leading neuroscientist at the University of California, Los Angeles' Center for Culture, Brain, and Development, points out that the parent-child connection during a child's first year can not only affect a child's psychological state, it actually plays a role in physically shaping the brain. Meanwhile, a study from the University of Bath, in England, has shown that placing 3- to 5-year-olds in day care can benefit the psychological well-being of both parent and child. "The research is now moving out of theoretical science and into practical science to the point where we can begin advising pediatricians about what advice to offer parents," Schore said. © 2005 ABC News Internet Ventures

Keyword: Development of the Brain
Link ID: 8272 - Posted: 06.24.2010

BUFFALO, N.Y. -- Male water fleas that scientists have never seen have made their debut in a University at Buffalo laboratory, providing biologists with their first glimpse of these elusive organisms. The UB research, published last month in Proceedings of the Royal Society: Biological Sciences, opens a new window on the biological diversity of several species of water fleas, including those in the genus Daphnia and the genus Bosmina, that play major roles in freshwater food webs. It also demonstrates that pesticides that mimic the hormone used in the UB experiments may have much broader effects than initially believed, and could damage populations of fish and other organisms higher up in the food chain. "Most freshwater fish eat water fleas at some point in their lives," said Derek J. Taylor, Ph.D., associate professor of biological sciences in UB's College of Arts and Sciences and co-author on the paper. "They are an important food source for fish." Water fleas are nearly microscopic organisms with transparent bodies. Found in lakes, ponds and other bodies of fresh water, they are crustaceans like lobsters and not insects, as their name suggests. © 2005 University at Buffalo.

Keyword: Sexual Behavior
Link ID: 8271 - Posted: 06.24.2010

University of Florida researchers have identified one possible reason for rising obesity rates, and it all starts with fructose, found in fruit, honey, table sugar and other sweeteners, and in many processed foods. Fructose may trick you into thinking you are hungrier than you should be, say the scientists, whose studies in animals have revealed its role in a biochemical chain reaction that triggers weight gain and other features of metabolic syndrome - the main precursor to type 2 diabetes. In related research, they also prevented rats from packing on the pounds by interrupting the way their bodies processed this simple sugar, even when the animals continued to consume it. The findings, reported in the December issue of Nature Clinical Practice Nephrology and in this month's online edition of the American Journal of Physiology-Renal Physiology, add to growing evidence implicating fructose in the obesity epidemic and could influence future dietary guidelines. UF researchers are now studying whether the same mechanism is involved in people. "There may be more than just the common concept that the reason a person gets fat is because they eat too many calories and they don't do enough exercise," said Richard J. Johnson, M.D., the J. Robert Cade professor of nephrology and chief of nephrology, hypertension and transplantation at UF's College of Medicine.

Keyword: Obesity; Chemical Senses (Smell & Taste)
Link ID: 8270 - Posted: 12.07.2005