By Susan Heavey and Lisa Richwine A veteran U.S. Food and Drug Administration scientist said Thursday the benefits of the pain relievers known as COX-2 inhibitors, a group that includes the withdrawn drug Vioxx as well as Celebrex and Bextra, do not appear to justify the risks of heart damage. Dr. David Graham, associate director for science and medicine at the FDA's Office of Drug Safety, spoke on the second day of an unusual three-day meeting called by the FDA after Merck & Co. pulled Vioxx from the market in late September. The FDA, which has come under fire in recent months as being slow to respond to serious drug side effects of drugs, is asking an advisory panel if COX-2 inhibitors offer enough benefits to stay on the market, if they and other over-the-counter pain relievers need stronger warnings, and if further research is needed. Graham said he saw a "class effect" of heart risk from the COX-2 inhibitors, and it appeared greater with higher doses. But he told the panel of FDA advisers that each drug should be evaluated individually. "The bottom line conclusion I came to is there really doesn't appear to be a need for COX-2 (inhibitors) ... I believe there is a (heart) effect and it's dose related," Graham told an FDA advisory panel. © Copyright 1996-2005 The Washington Post Company

Keyword: Pain & Touch
Link ID: 6903 - Posted: 06.24.2010

WASHINGTON, DC--Gender, often said to depend solely upon anatomy or hormones, may depend also on hard-wired genetics, according to new research that could help doctors and lawyers better understand the one in 4,000 babies born with both male and female traits. "The biology of gender is far more complicated than XX or XY chromosomes and may rely more on the brain's very early development than we ever imagined," researcher Eric Vilain, M.D., reported today at the American Association for the Advancement of Science (AAAS) Annual Meeting in Washington, D.C. "Surgical sex assignment of newborns with no capacity to consent should never be performed for cosmetic reasons, in my opinion," said Vilain, an associate professor of human genetics who also serves as a chief of medical genetics and director of research in urology and sexual medicine within the David Geffen School of Medicine at the University of California, Los Angeles. "We simply don't know enough yet about gender to be making surgical or legal assumptions." Another AAAS speaker, William G. Reiner, M.D., agreed. "The most important sex organ is the brain," said Reiner, a psychiatrist and associate professor in the Department of Urology, Oklahoma University Health Science Center. "We have to let these children tell us their gender at the appropriate time." An estimated 1 in 4,000 to 1 in 5,000 babies may be classified as "gender ambiguous" because intersex conditions affecting their genitalia, reproductive systems or sex chromosomes make an immediate assessment impossible, Reiner explained.

Keyword: Sexual Behavior
Link ID: 6902 - Posted: 02.19.2005

Bigger is smarter is better. That's the conventional wisdom for why the human brain gradually became three times larger than the ancestral brain. "But bigger brains were not generally smarter brains," said neurobiologist William H. Calvin at the American Association for the Advancement of Science meeting in Washington, D.C. on Friday, Feb. 18. "Thanks to the archaeologists, we know that our ancestors went through two periods, each lasting more than a million years, when toolmaking techniques didn't gradually improve, despite a lot of gradual brain size increase." There is no lack of other candidates for why a bigger brain would be better. Calvin, who is affiliate professor of psychiatry and behavioral sciences at the University of Washington in Seattle, emphasized the detailed planning needed as you get set to throw. "In hunting, you have to be right the first time, or dinner runs away, but there are other strong candidates such as the brain space needed to use words in short sentences," noted Calvin. "You need something similar for extensive sharing. You have to keep track of who owes what to whom, so as to avoid cheaters. And that's a task similar to saying who did what to whom." The problem is that, whatever the drivers were, they didn't produce a general cleverness that showed up in toolmaking techniques. What's even worse for the bigger-is-smarter-is-better hypothesis, Calvin said, is that after Homo sapiens was walking around Africa 200,000 years ago with a brain of our size, we spent – with a few exceptions – the next 150,000 years doing more of the same.

Keyword: Evolution; Intelligence
Link ID: 6901 - Posted: 06.24.2010

A procedure's serendipitous success hints that some headaches start in the heart Ben Harder Neurologist Roman Sztajzel received an unexpected letter in 1999 from a patient he had last seen a year and a half earlier. The Swiss woman thanked him for curing her of migraines, which she had experienced frequently into her early 30s. But Sztajzel hadn't treated her for migraines. He'd seen her because she'd had a stroke. Another stroke soon followed. Neither brain attack showed any sign of a typical cause. In search of an explanation, Sztajzel and his colleagues had screened the woman for an abnormal opening between the heart's upper chambers. That opening functions in human fetuses to let the circulating blood bypass the lungs, which the body doesn't rely on until a newborn starts breathing air. At or shortly after birth, tissue flaps in the heart usually fuse and close the hole. But in about a quarter of the U.S. population, complete closure never occurs. The residual tunnel, called a patent foramen ovale (PFO), can act as a valve. It's normally shut but occasionally shunts blood that's headed to the lungs off to the brain and other parts of the body. Most of the millions of people who have a PFO are never screened for it because doctors rarely suspect it of causing health problems. But in some cases, blood clots passing through the PFO can shoot to the head and trigger strokes. Air bubbles and dissolved chemicals can also slip through the one-way shunt rather than ride to the lungs, where they'd be exhaled or broken down. Copyright ©2005 Science Service.

Keyword: Pain & Touch
Link ID: 6900 - Posted: 06.24.2010

Christen Brownlee By flipping on a gene that's normally active only during embryonic development, researchers have restored hearing to a group of profoundly deaf guinea pigs. The finding may lead to treatments for millions of people with acquired hearing loss, the team says. Like people, guinea pigs use auditory hair cells, found deep inside the inner ear, to detect sounds. When sound waves reach them, the cells' hairlike projections sway with the vibrations and transmit electrical signals to the brain's auditory center. Permanent damage to the sensitive cells by aging, diseases, certain medications, and even loud sounds is the most common cause of acquired hearing loss in people. "The only biological way to induce recovery is by generating new hair cells," says Yehoash Raphael of the University of Michigan Medical School in Ann Arbor. Two years ago, Raphael and his colleagues succeeded in regrowing hair cells in adult guinea pigs (SN: 6/7/03, p. 355: http://www.sciencenews.org/articles/20030607/fob1.asp). However, the team had no evidence that the new hair cells detected sound or connected properly with the brain. Copyright ©2005 Science Service

Keyword: Hearing; Regeneration
Link ID: 6899 - Posted: 06.24.2010

HOUSTON, – If you crammed for tests by pulling 'all nighters' in school, ever wonder why your memory is now a bit foggy on what you learned? A University of Houston professor may have the answer with his research on the role of circadian rhythms in long-term learning and memory. Arnold Eskin, the John and Rebecca Moores Professor of Biology and Biochemistry at UH, was recently awarded two grants totaling $2,472,528 from the National Institutes of Health (NIH) to continue pursuing his investigations of memory formation and the impact of the biological clock on learning and memory. Scientists have known for a while that the brain's biological (or circadian) clock influences natural body cycles, such as sleep and wakefulness, metabolic rate and body temperature. New research from Eskin suggests the circadian clock also may regulate the formation of memory at night. This new research focuses on "Circadian Modulation of Long-term Memory Formation" and "Long-term Regulation of Glutamate Uptake in Aplysia," with NIH funding to be disbursed over four years. "There is a lot of research going on in memory," Eskin said. "How do we remember things given that we don't have a camera in our brain to record events? What changes take place in our brains that allow us to remember? These grants are about fundamental learning and memory and about modulation of memory."

Keyword: Biological Rhythms; Learning & Memory
Link ID: 6898 - Posted: 06.24.2010

WASHINGTON, DC - Researchers have noted a higher incidence of depression among patients with epilepsy than the general population or others with chronic conditions such as diabetes. For a long time, depression was thought to be a complication of epilepsy. But there is evidence that the connection between epilepsy and depression may be a two-way street, according to research carried out in Sweden and the United States and reviewed at the annual meeting of the American Association for the Advancement of Science (AAAS). "People with a history of depression have a 3 to 7 times higher risk of developing epilepsy," said Dr. Andres Kanner, a specialist on epilepsy at Rush University Medical Center in Chicago. "This kind of information is forcing us to take a second look at the interaction between depression and epilepsy." Since depression affects about 5.3 percent of the U.S. population and epilepsy about 0.5 to 1 percent, session organizers said, knowledge of any relationships between the two disorders could help physicians find ways to improve care for both groups. The two-way relationship between epilepsy and depression could mean common pathogenic mechanisms are at work, Kanner said.

Keyword: Epilepsy; Depression
Link ID: 6897 - Posted: 02.19.2005

Shared properties of human languages are not the result of universal grammar but reflect self-organizing properties of language as an evolving system The forces of variation and selection which shape human language have become issues of extensive research. Documentation of sounds and sound patterns, and their evolution over the past 7000-8000 years allows linguists to quantify the important role of human perception, articulation and imperfect learning as language is passed from one generation to the next. At this year's AAAS conference in Washington, DC, Juliette Blevins, senior scientist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, presents a new approach to the problem of how genetically unrelated languages across the world often show similar sound patterns, without invoking innate mechanisms specific to grammar. Languages as far apart as Native American, Australian Aboriginal, Austronesian and Indo-European show similar patterns of vowel and consonant inventory and distribution, but exceptions to sound patterns regarded as universal show that these similarities are best viewed as the result of convergent evolution. A new model of sound change shows that evolutionary principles can account for striking phonetic similarities across unrelated languages, as well as the rarity of certain sounds. German and Russian are not the only languages in the world where sounds like b, d, and g lose their characteristic vocal fold 'buzz' at the end of the word. Dozens of unrelated languages, from Afar on the sands of Ethiopia, to Ingush in the northern Caucasus have similar sound patterns.

Keyword: Language; Evolution
Link ID: 6896 - Posted: 02.19.2005

A drug used to treat patients with Alzheimer's disease could actually make their condition worse, a study says. Quetiapine (Seroquel) is commonly used in nursing homes to combat agitation, a common symptom of Alzheimer's. But research by Institute of Psychiatry experts in the British Medical Journal online suggests it could significantly speed up the rate of patients' decline. However, a spokesman for AstraZeneca, which makes Seroquel, said the drug was safe and effective. Antipsychotic drugs such as quetiapine are used in up to 45% of nursing homes to treat agitation, which is a common and distressing symptom of dementia. They are also used to treat schizophrenia. Ninety-three patients at care homes in the north-east of England who had Alzheimer's, dementia and significant levels of agitation were studied over six months. They were split into three groups. One was given a daily dose of quetiapine, another was given the "anti-dementia" drug rivastigmine, and the third a dummy pill. Researchers then assessed their agitation levels and cognitive abilities, such as memory skills, throughout the study. Forty-six patients completed cognitive assessments after six weeks. The 14 who were taking quetiapine registered an average drop of around 14 points on the scale used to assess decline, compared to almost no change for those taking the dummy pill. (C)BBC

Keyword: Alzheimers
Link ID: 6895 - Posted: 02.18.2005

To most people, cochlear implants sound like a medical miracle—a device the size of a candy corn that can correct the inability to hear. But many in the Deaf community see the technology as a cultural threat, yet another example of the hearing world’s inability to really listen. When Angie Mucci’s daughter Allie was born nearly three years ago, she knew her little girl was special. What she didn’t know—and wouldn’t discover until a year later, when it was clear Allie wasn’t responding to even the loudest noises—was that her daughter is deaf. Just a few decades ago, children with hearing loss as profound as Allie’s had two choices if they wanted to learn to communicate: lip-reading or sign language. But Allie and her mom were given a third option: surgical implantation of a “bionic ear,” or cochlear implant, that would help Allie hear. “I am all for giving my daughter every opportunity she has out of life,” says Mucci, a twenty-nine-year-old Las Vegas resident who, like an estimated ninety percent of parents with deaf children, can hear. For Mucci, that meant enrolling her daughter in an implant study in San Antonio, Texas, where Allie underwent surgery on her right ear at the age of thirteen months. Before the operation, Allie could hear only sounds that measured at 110 decibels or louder, a sound volume that compares with what you might hear when seated in the front row of a rock concert. With her cochlear implant, and no visual cues, Allie can now detect sounds that clock in at a mere twenty decibels. Mucci is currently scheduling a second surgery, this time on Allie’s left ear, with the doctors who performed the first operation. © 2002 Science & Spirit Magazine.

Keyword: Hearing
Link ID: 6894 - Posted: 06.24.2010

Eating fish is a healthy choice because its' one of the best sources of beneficial fats called omega-3 fatty acids. But some people are also cautioned to watch out for certain fish because of high levels of mercury. "The problem with mercury is, if it's ingested at very high levels, for certain populations it can cause damage to our nervous systems," says Charles Santerre, associate professor of foods and nutrition and food science at Purdue University. "Our greatest concern is women of child-bearing age, because women who become pregnant or are nursing can pass mercury either through the placenta or through their milk, and the levels that get to the fetus or the nursing infant can be high enough, in some instances, to cause injury to the baby." In March of 2004 the Food and Drug Administration and the Environmental Protection Agency recommended that sensitive populations—women who are pregnant or might become pregnant, nursing mothers, and young children—should avoid eating large ocean fish like swordfish, tilefish, king mackerel, and shark. But what about the most commonly eaten fish, like tuna? Canned tuna is eaten by 96 percent of American households, and represents the number three item in U.S. grocery stores (behind sugar and coffee) based on dollar sales per linear foot of shelf space. © ScienCentral, 2000- 2005.

Keyword: Neurotoxins; Development of the Brain
Link ID: 6893 - Posted: 06.24.2010

By Shankar Vedantam, Washington Post Staff Writer Adults taking popular antidepressants such as Prozac, Paxil and Zoloft are more than twice as likely to attempt suicide as patients given sugar pills, according to an analysis released yesterday of hundreds of clinical trials involving tens of thousands of patients. The results mirror a recent finding of the Food and Drug Administration that the drugs increase suicidal thoughts and behavior among some children, and offer tangible support to concerns going back 15 years that the mood-lifting pills have a dark side. The examination of 702 controlled clinical trials involving 87,650 patients is the most comprehensive look at the subject and is particularly telling because it counted suicide attempts and included patients treated for a variety of conditions, including sexual dysfunction, bulimia, panic disorder and depression. Experts cautioned, however, that the risks should be balanced against the drugs' benefits. They have been shown to be effective against depression and a host of other disorders in adults, a positive track record largely missing in tests of the drugs on children. © Copyright 1996-2005 The Washington Post Company

Keyword: Depression
Link ID: 6892 - Posted: 06.24.2010

Following the Asian tsunami, scientists struggled to explain reports that primitive aboriginal tribesmen had somehow sensed the impending danger in time to join wild animals in a life-saving flight to higher ground. While some scientists discount the existence of a sixth sense for danger, new research from Washington University in St. Louis has identified a brain region that clearly acts as an early warning system -- one that monitors environmental cues, weighs possible consequences and helps us adjust our behavior to avoid dangerous situations. "Our brains are better at picking up subtle warning signs than we previously thought," said Joshua Brown, Ph.D., a research associate in psychology in Arts & Sciences and co-author of a study on these findings in the Feb. 18 issue of the journal Science. The findings offer rigorous scientific evidence for a new way of conceptualizing the complex executive control processes taking place in and around the anterior cingulate cortex (ACC), a brain area located near the top of the frontal lobes and along the walls that divide the left and right hemispheres.

Keyword: Emotions
Link ID: 6891 - Posted: 02.18.2005

Understanding the biology of memory is a major goal of contemporary neuroscientists. Short-term or "working" memory is an important process that enables us to interact in meaningful ways with others and to comprehend the world around us on a moment-to-moment basis. A study published this week in Science (February 18) presents a strikingly simple yet robust mathematical model of how short-term memory circuits in the brain are likely to store, process, and make rapid decisions about the information the brain receives from the world. A classic although purely practical example of working memory is our ability to look up a telephone number, remember it just long enough to dial it, and then promptly forget it. However, working memory is fundamental to many other cognitive processes including reading, writing, holding a conversation, playing or listening to music, decision-making, and thinking rationally in a general sense. Cold Spring Harbor Laboratory computational neuroscientist Carlos Brody (brody@cshl.edu) explores how brain neurons interact with each other to form the circuits or "neural networks" that underlie working memory and other rapid and flexible cognitive processes. In the new study, Brody's group developed a mathematical model for interpreting data collected at Universidad Nacional Autónoma de México by his collaborator Rodolfo Romo. Romo's group measured brain neuron activity of macaque monkeys while the animals performed a simple task that involves working memory.

Keyword: Learning & Memory
Link ID: 6890 - Posted: 02.18.2005

UC Irvine researchers have uncovered significant differences in the brain activity of men and women when engaged in a broad range of activities and behavior – differences that are even more acute during impulsive or hostile acts. But when men and women have nicotine in their bodies, these brain activity differences practically disappear. Among both smokers and non-smokers on nicotine, during aggressive moments such as impulsive or hostile acts, there are virtually no differences in brain activity between the sexes – illustrating how nicotine can impact brain function. Results of the study, conducted by Brain Imaging Center researchers supported by the UCI Transdisciplinary Tobacco Use Research Center, are published in the online edition of the International Journal of Neuropsychopharmacology, and will be available in print next month. The researchers found during behavioral and brain-imaging tests on hostility and impulsive reaction that brain-metabolism activity – which indicates when neurons are working – was much higher in many brain areas of women than men. But when the test subjects were given nicotine, metabolic activity significantly declined in the women and slightly increased in men – the original differences all but disappeared. © Copyright 2002-2005 UC Regents

Keyword: Sexual Behavior; Drug Abuse
Link ID: 6889 - Posted: 06.24.2010

By DENISE GRADY Women in labor may suffer needlessly because doctors mistakenly advise them to delay a common pain treatment for fear that it will impede contractions and lead to a Caesarean section, researchers are reporting. A new study of the treatment - a type of anesthesia that injects painkiller into the spinal fluid and the epidural area around the spinal cord to numb the pelvic region - finds that giving it early or late in labor makes no difference in Caesarean rates among women having first babies. There is no reason for women to deny themselves the medicine or for doctors to withhold it, the study says. Other researchers urged caution, noting that not all hospitals offer such combined anesthesia and that the findings might not apply to all epidural treatments. About 60 percent of American women have epidural anesthesia during childbirth. Dr. Cynthia A. Wong, the lead author of the new study and an obstetric anesthesiologist at Northwestern Memorial Hospital in Chicago, said women were often pressured to delay the treatment and made to feel guilty or weak if they asked for one too soon. Copyright 2005 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 6888 - Posted: 02.17.2005

DALLAS – – New findings by researchers at UT Southwestern Medical Center challenge one of the established views of how nerve cells communicate with one another. Every time we move, feel emotions, think or remember, the nerve cells, or neurons, in our body transmit messages to one another via chemical signals called neurotransmitters. Within neurons are tiny organelles called synaptic vesicles that sequester neurotransmitters and release them when needed into the synapse, or space between nerve cells, where the chemical signal is transmitted to other neurons. It is known that synaptic vesicles release their neurotransmitters in two different "modes" – one when the neuron is stimulated and actively relaying a message, and the other through spontaneous release when the neuron is "at rest," or inactive. Until now it was believed that the same synaptic vesicles were responsible for releasing neurotransmitters in both modes. However, new research by UT Southwestern scientists appearing in the Feb. 17 issue of the journal Neuron suggests that two distinct types of synaptic vesicles are responsible for the two different modes of neurotransmitter release – one type of vesicle for spontaneous release, another vesicle associated with activity-dependent release.

Keyword: Miscellaneous
Link ID: 6887 - Posted: 06.24.2010

With obesity having reached epidemic levels around the world, nutrition experts are always telling us to eat better. So, what if each bite of a hamburger conjured up unpleasant memories? Psychologist Elizabeth Loftus from the University of California, Irvine suggests that changing people's memories might alter their behavior. "If we made people believe that they got sick eating a particular food, maybe we would be able to show that down the road they didn't want to eat that food as much," Loftus explains. She was able to convince about a third of a group of volunteers that had had a bad experience as a child after eating certain foods. "We were able to make people believe that they had gotten sick eating this particular food." Studying memory and memory manipulation for quite some time, Loftus and her research team, as well as collaborators at The University of Washington, have worked to reveal how things that we are told can change our memories. "We've done quite a few studies where we either distort memory for a detail here or there, or we plant an entirely false memory," Loftus says. Food-related memories seemed like an obvious choice as an easy way to see a consequence that they could look for. "We were looking for a false belief or a false memory that we could plant that would allow us to measure the subsequent repercussions of adopting this false memory." © ScienCentral, 2000- 2005.

Keyword: Learning & Memory
Link ID: 6886 - Posted: 06.24.2010

Researchers have long puzzled over the apparently multiple causes of complex developmental disorders such as schizophrenia. Individuals seem to be predisposed to the disease by a tragic, mysterious combination of genetics, prenatal trauma, viral infection, and early experience. And its array of symptoms--including hallucinations, delusions, paranoia, and antisocial behavior--has defied simple explanation. In experiments with rats, however, researchers led by led by Gerard J.M. Martens of the Nijmegen Center for Molecular Life Sciences (NCMLS) have demonstrated that such seemingly diverse combinations of symptoms can arise from a subtle imbalance in the activity of a single gene whose protein plays a key role in neural development. The researchers studied the genetic differences between rats bred to be either resistant or susceptible to the drug apomorphine. A long history of studies has revealed that apomorphine-susceptible rats show many behavioral and biochemical differences from normal rats. What's more, the tendency to develop these differences depends on their exposure to stress in early life.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 6885 - Posted: 02.17.2005

By Karen Wright Let’s start with a straightforward fact: Mercury is unimaginably toxic and dangerous. A single drop on a human hand can be irreversibly fatal. A single drop in a large lake can make all the fish in it unsafe to eat. Often referred to as quicksilver, mercury is the only common metal that is liquid at room temperature. Alchemists, including the young Sir Isaac Newton, believed it was the source of gold. In the modern era, it became a common ingredient of paints, diuretics, pesticides, batteries, fluorescent lightbulbs, skin creams, antifungal agents, vaccines for children, and of course, thermometers. There is probably some in your mouth right now: So-called silver dental fillings are half mercury. Mercury is also a by-product of many industrial processes. In the United States coal-fired power plants alone pump about 50 tons of it into the air each year. That mercury rains out of the sky into oceans, lakes, rivers, and streams, where it becomes concentrated in the flesh of fish, shellfish, seals, and whales. Last year the Food and Drug Administration determined there is so much mercury in the sea that women of childbearing age should severely limit their consumption of larger ocean fish. The warning comes too late for many mothers. A nationwide survey by the Centers for Disease Control shows that one in 12 women of childbearing age already have unsafe blood levels of mercury and that as many as 600,000 babies in the United States could be at risk. But that begs a critical question: At risk for what? © 2004 The Walt Disney Company

Keyword: Neurotoxins
Link ID: 6884 - Posted: 06.24.2010