AFP — New evidence has emerged that Neanderthals coexisted with anatomically modern humans for at least a thousand years in central France, a finding that suggests these enigmatic hominids came to a tragic and lingering end. Few chapters in the rise of Homo sapiens sapiens, as modern humans are known, have triggered as much debate as the fate of the Neanderthals. Smaller and squatter than H. sapiens but with larger brains, Neanderthals lived in Europe, parts of central Asia and the Middle East for around 170,000 years. But vestiges of the Neanderthals stop between 28,000 and 30,000 years ago. At that point, H. sapiens, a smart, ascendant sub-species of humans originating in East Africa, became the undisputed master of the planet. One intriguing school of thought is that the Neanderthals did not suddenly disappear off the map, but in fact gradually melded in with H. sapiens culturally, and possibly sexually. Interbreeding resulted, meaning that what we, today, supposedly carry some of the genetic legacy of the Neanderthals. Copyright © 2005 Discovery Communications Inc.

Keyword: Evolution
Link ID: 7840 - Posted: 06.24.2010

By Charles Clover, Environment Editor Cases of the human race being helped by rats are few - and to date have been confined to laboratories, or sieges when everything else has been eaten. All that may be about to change, however, because scientists now believe the rodent could answer the needs of people in countries blighted by landmines. Half a century of dirty wars has left more than 100 million landmines planted in the developing world. They continue to kill, maim and blight the land long after the end of the wars during which they were laid. Until now, removing mines has been the job of technicians with bomb-proof lorries and metal detectors. But metal detectors cannot trace mines made of wood or plastic or distinguish unexploded mines from shrapnel. Now scientists have shown that rats can be trained to be a safe, fast, reliable and cheap method of locating mines of all kinds, according to this month's issue of BBC Wildlife, published today. "People thought I was mad in the beginning," Bart Weetjens, of the Belgian research organisation Apopo, told the magazine. He has been experimenting with 300 giant pouched rats, cricetomys gambianus, in the mountains of Morogoro, Tanzania. © Copyright of Telegraph Group Limited 2005

Keyword: Chemical Senses (Smell & Taste)
Link ID: 7839 - Posted: 06.24.2010

A UCSF study has found that a specific signaling link between neurons and muscles in the fruit fly is essential for keeping the insect's nervous system stable. The findings are relevant for ongoing research in identifying causes and developing treatments for neuromuscular neurodegenerative diseases in humans, such as amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, says study co-author Graeme Davis, PhD, associate professor and vice chair of the Department of Biochemistry and Biophysics at the University of California, San Francisco. "If we want to make new drugs to treat neurodegenerative disease, then we have to identify new drug targets, and our study findings present that potential," he says. "This study is a significant step forward because we have shown that a signaling system composed of several genes is important for keeping the nervous system stable." The findings are reported in the September issue of the journal Neuron. The nervous system is a complex pattern of connections that exists for the entire life of the organism, and understanding how the myriad patterns and pathways of these connections are maintained for long periods of time presents an ongoing challenge to scientists, says Davis.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 7838 - Posted: 09.02.2005

No matter how much you might hate hearing it, you know you do have you mother's eyes, or her hair, or her smile. How much you resemble your mother depends on which of her genes you inherit. But looking like her is not the only hold your mom's genes have on your life. There's mounting evidence that mom's genes may indirectly affect your weight and your health all the way into adulthood. "Not only are your genes important, and your environment — that is, how much you eat, how much dietary fat you eat — but also mom's genes are important," says geneticist Joseph Jarvis, perhaps influencing how your body is affected by what you eat. Jarvis, a researcher at Washington University School of Medicine in St. Louis, says that's because our mother's genes somehow affect how our bodies react to our prenatal and early environment (while nursing), switching certain of our genes on or off. This could have consequences throughout our lives, affecting our weight that could lead to health issues such as diabetes and high cholesterol. According to Jarvis, much of the earlier research into this effect had looked at weight gain of very young mice. This is because for "a two-week-old mouse, the only source of food they have is mother's milk. And we know that in mice, milk production has a genetic basis," he explains. "So it makes sense for the two-week weight to depend on who your mother was." © ScienCentral, 2000-2005.

Keyword: Obesity; Genes & Behavior
Link ID: 7837 - Posted: 06.24.2010

(Newark)-Life is full of choices. But how do individuals know what their preferences are and how do they act on them? And what leads mothers to make choices that benefit or lead to neglect of her offspring? Based on research performed using laboratory rats, a team of neuroscience researchers at Rutgers University-Newark suggest that an intricate system exists within the brain for establishing individual preferences, which ultimately impacts choices. In the article, "Preference for cocaine-versus pup-associated cues differentially activates neurons expressing either Fos or CART in lactating, maternal rodents," which is in press for the September 2005 volume of the journal Neuroscience (the article currently appears online at www.sciencedirect.com) Rutgers-Newark neuroscience professor Joan Morrell and her colleague Brandi Mattson reveal that individual preferences can be linked to the activation of specific sets of neurons within the brain. The researchers used postpartum rats in order to establish preferences and analyze how the mother rats' brains functioned when they selected an environment associated with their pups or another environment associated with the drug cocaine. In the experiment, rats learned over four days in which distinct environments they had access to their pups versus where they had access to cocaine. Following a 24-hour wait, the rats were given the opportunity to choose either the environment where they anticipated they would find either their pups or where they would find cocaine.

Keyword: Drug Abuse
Link ID: 7836 - Posted: 09.02.2005

By Tracy Staedter, Discovery News The ability to express feelings is difficult enough for humans, but now a humanoid robot named Kansei is able to frown or smile according to a flow of artificial consciousness. Kansei's ability to communicate feelings makes it one step closer to recognizing when humans are happy or sad, an important characteristic for machines expected to one day help care for the elderly, clean house, or greet people at a reception desk. Kansei, which means "sensibility" and "emotion" in Japanese, also contains speech recognition software, a speaker to vocalize, and motors that contort artificial skin on its face into expressions. The robot could even one day learn to distinguish and articulate whether foods taste good or bad. "If we establish the mechanism, the robot could find nice food in a market and even research new delicious foods for humankind," said the Kansei project leader Junichi Takeno, a professor at the Robot and Science Institute of Meiji University in Japan. Copyright © 2005 Discovery Communications Inc.

Keyword: Emotions
Link ID: 7835 - Posted: 06.24.2010

Roxanne Khamsi Human remains in cattle feed could have caused the first case of mad cow disease, two UK researchers propose. The hypothesis seeks to answer lingering questions about the fatal infection, which has affected 180,000 cows in Britain alone since the mid-1980s, and has gone on to cause more than 100 deaths in humans. Alan Colchester of the University of Kent and his daughter Nancy Colchester, of the University of Edinburgh, point out that during the 1960s and 1970s Britain imported hundreds of thousands of tonnes of whole and crushed bones and animal carcasses. These were used for fertilizer and to feed livestock. Nearly 50% of these imports came from Bangladesh, where peasants gathering animal materials may have also picked up human remains, the researchers say. Other experts in the field view the idea with scepticism, saying that proof remains circumstantial. "The argument isn't very compelling because there's no smoking gun evidence," says Surachai Supattapone, an expert in infectious diseases at Dartmouth Medical School in Hanover, New Hampshire. ©2005 Nature Publishing Group

Keyword: Prions
Link ID: 7834 - Posted: 06.24.2010

Use of a type of anti-depressant medication during pregnancy may increase the risk of birth defects such as cleft palate, research suggests. Danish and US scientists found use of SSRIs in the first three months of pregnancy was linked to a 40% increased risk - but the results are preliminary. Cardiac defects appeared to be 60% more likely when the women used SSRIs. But the researchers stress the results, featured in Pulse magazine, do not mean women should stop taking the drugs. The findings were presented an International Society for Pharmacoepidemiology conference. SSRIs, or Selective Serotonin Re-uptake Inhibitors, include commonly prescribed drugs such as Prozac and Seroxat. They work by boosting levels of the mood chemical serotonin in the brain. Their use during pregnancy was linked to withdrawal symptoms in newborn babies in a study published in The Lancet earlier this year. And doctors have been told not to prescribe them to children because of an increased risk of suicide. In the latest study, focusing on 1,054 women who took SSRIs during pregnancy, scientists also found that use of the drugs late in pregnacy was associated with a 40% increased risk of premature birth. And a second study of 377 cases of persistent pulmonary hypertension in babies found SSRI use late in pregnancy was linked a 5.5-fold increased risk. (C)BBC

Keyword: Depression; Development of the Brain
Link ID: 7833 - Posted: 09.01.2005

By Marc Kaufman Washington Post Staff Writer The top Food and Drug Administration official in charge of women's health issues resigned yesterday in protest against the agency's decision to further delay a final ruling on whether the "morning-after pill" should be made more easily accessible. Susan F. Wood, assistant FDA commissioner for women's health and director of the Office of Women's Health, said she was leaving her position after five years because Commissioner Lester M. Crawford's announcement Friday amounted to unwarranted interference in agency decision-making. "I can no longer serve as staff when scientific and clinical evidence, fully evaluated and recommended for approval by the professional staff here, has been overruled," she wrote in an e-mail to her staff and FDA colleagues. Crawford said last week that unresolved regulatory issues made it impossible to approve expanded use of the emergency contraceptive. Wood said the decision was widely seen in the FDA as political. "Many colleagues have made it known that they are deeply concerned about the direction of the agency," she said in an interview. Wood also said other FDA officials who are typically involved in important matters were kept in the dark about the contraceptive, called Plan B, until Crawford announced his decision, which she believed was made at higher levels in the administration. Wood said that when she asked a colleague in the commissioner's office when the decision would be made, the answer was, "We're still awaiting a decision from above; it hasn't come down yet." © 2005 The Washington Post Company

Keyword: Sexual Behavior
Link ID: 7832 - Posted: 06.24.2010

Scientists at New York University School of Medicine report in a new study that they have identified the molecular switch that turns on the production of myelin, the fatty insulation around nerve cells that ensures swift and efficient communication in the nervous system. The study, published in the September 1, 2005, issue of the journal Neuron, may provide a new avenue for treating nervous system diseases such as multiple sclerosis, which are associated with damage to myelin. A team led by James L. Salzer, M.D., Ph.D., Professor of Cell Biology and Neurology at NYU School of Medicine, identified the long-sought factor that determines whether or not nerve cells will be wrapped in thick layers of myelin, producing the biological equivalent of a jelly roll. Using a sophisticated system for growing nerve cells in laboratory dishes, the team identified a gene called neuregulin as the myelin signal. This signal directs Schwann cells, the nervous system's cellular architects, to build elaborate sheaths of myelin around the axons of nerve cells. Axons are the long cable-like arms of nerve cells that send messages to other cells. The construction of myelin sheath has been called one of the most beautiful examples of cell specialization in nature. Myelin forms the so-called white matter in the nervous system and constitutes 50 percent of the weight of the brain. It is also an important component of the spinal cord, and of nerves in other parts of the body. It has been known for almost 170 years that there are two kinds of axons --one is wrapped in myelin and appears white and the other is not and appears gray.

Keyword: Glia
Link ID: 7831 - Posted: 09.01.2005

Scientists at the University of Liverpool have discovered that the human brain favours familiar-looking faces when choosing a potential partner. The research team found that people find familiar faces more attractive than unfamiliar ones. They also found that the human brain holds separate images of both male and female faces and reacts to them differently depending on how familiar it is with their facial features. Dr Anthony Little, from the University's School of Biological Sciences, examined whether early visual experience of male and female faces affected later preferences. The research team asked over 200 participants to view a number of human faces that had been digitally manipulated to change their facial characteristics. Dr Little said: "We found that participants preferred the face that they were most visually familiar with. In one of the tests we showed participants a block of faces with wide-spaced eyes and then asked them to compare these with a face that had narrow-spaced eyes. We found that participants preferred the face with wide-spaced eyes, suggesting that the brain connects familiarity with attraction." The team also asked participants to judge the same preferred facial features in those of the opposite sex. Participants who were shown male faces with wide-spaced eyes preferred this trait in subsequent male faces but not in female faces.

Keyword: Sexual Behavior
Link ID: 7830 - Posted: 09.01.2005

Just as travelers figure out which restaurant is good by the numbers of cars in the parking lot, bumblebees decide which flowers to visit by seeing which ones already have bee visitors. Bumblebees that watched other bees forage on green artificial flowers were twice as likely to choose the green flowers over orange flowers when it was their turn to forage, according to new research. The finding is the first demonstration that insects can learn by just watching the behavior of other insects. "Studying a variety of different animals -- everything from chimpanzees to bees -- that show some kind of social learning, will give us a better understanding of how social learning occurs," said behavioral ecologist Bradley D. Worden of The University of Arizona in Tucson. "One of the cool things we're finding out from bees is that complex behavior and advanced forms of learning can come from small brains." Worden, a postdoctoral research associate in UA's department of ecology and evolutionary biology, conducted his work on the brainy bees with Daniel R. Papaj, a UA professor of ecology and evolutionary biology. The team's report has been released online and will be published in an upcoming issue of Biology Letters of the Royal Society. The National Science Foundation funded the research. Charles Darwin was one inspiration for the study because he wrote about the possibility that honeybees were watching and learning from bumblebees, Worden said.

Keyword: Learning & Memory
Link ID: 7829 - Posted: 09.01.2005

One of the neural oddities of "declarative" memory--the recall of past things and events--is that some experiments have shown that recognizing a familiar object is accompanied by a reduction in activity of the brain's memory centers in the medial temporal lobe. Such a reduction seems counterintuitive, since remembering seems to be a positive event. Now, researchers led by Anthony D. Wagner, Brian D. Gonsalves, and Itamar Kahn of Stanford University have documented this reduced activity in humans and have demonstrated that the magnitude of the dip corresponds with the familiarity of the objects. In their experiments reported in the September 1, 2005, issue of Neuron, the researchers asked volunteers to look at series of faces as the subjects' brains were scanned using either of two techniques. One was functional magnetic resonance imaging (fMRI), which gives information on the location and amount of activation of brain regions, and the other was magnetoencephalography (MEG), which reports the precise timing of brain responses. The technique of fMRI uses harmless magnetic fields and radio waves to map blood flow in the brain, which reflects brain activity, and MEG detects the infinitesimal magnetic fields generated by brain electrical activity. The researchers asked the subjects to rate their familiarity with each face as "remembering" if they strongly recalled the face, "knowing" if they had a feeling of recognizing the face, or "new" if they didn't recall seeing the face before.

Keyword: Learning & Memory
Link ID: 7828 - Posted: 09.01.2005

Roxanne Khamsi Deciding between a risky financial investment and a safe one sets two parts of the brain into competition, say researchers in California. As centres for pleasure and anxiety battle it out, a simple brain scan of the two can actually predict what a person will chose to do a few seconds before they do it: when joy beats worry in our brain, a risky decision is made. Studies of how the mind handles risky behaviour have highlighted a number of neural hotspots. One is a peanut-sized region of the brain called the nucleus accumbens, which is loaded with the molecule dopamine and becomes active in anticipation of pleasure. The nucleus accumbens is known to play a role in the addictive affect of drugs. Another region, known as the anterior insula, is stimulated in anticipation of a bad sensation. This area lights up in those predicting the onset of physical pain, and in generally anxious individuals. Neuroscientist Brian Knutson of Stanford University and his colleague Camelia Kuhnen sought to compare how these two brain regions interact by asking 20 volunteers to play an investment game for a cash reward. ©2005 Nature Publishing Group

Keyword: Emotions; Drug Abuse
Link ID: 7827 - Posted: 06.24.2010

Michael Hopkin Good news for lovers of extra-virgin olive oil: besides being delicious on salads, it also contains a compound that mimics the effects of ibuprofen. So a Mediterranean-style diet might give you the supposed long-term benefits of that drug, such as a reduced cancer risk. A daily dose of 50 g or 4 tablespoons of olive oil confers the equivalent of around 10% of the recommended ibuprofen dose for adult pain relief, say researchers led by Paul Breslin of the Monell Chemical Senses Center at the University of the Sciences in Philadelphia, who discovered the effect. So although it won't cure a headache, it may give you some of the long-term benefits of repeated ibuprofen use, including helping to ward off Alzheimer's. The compound, called oleocanthal, acts in the same way as ibuprofen to stifle components of a pain pathway called the prostaglandin system. This is in spite of the two chemicals' very different structures, the team reports in Nature1. The compound should be present in any extra-virgin oil, Breslin says. But concentrations will vary depending on a range of factors, such as the variety of olive, and the age of the olives at pressing. ©2005 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 7826 - Posted: 06.24.2010

WASHINGTON, - The first comprehensive comparison of the genetic blueprints of humans and chimpanzees shows our closest living relatives share perfect identity with 96 percent of our DNA sequence, an international research consortium reported today. In a paper published in the Sept. 1 issue of the journal Nature, the Chimpanzee Sequencing and Analysis Consortium, which is supported in part by the National Human Genome Research Institute (NHGRI), one of the National Institutes of Health (NIH), describes its landmark analysis comparing the genome of the chimp (Pan troglodytes) with that of human (Homo sapiens). "The sequencing of the chimp genome is a historic achievement that is destined to lead to many more exciting discoveries with implications for human health," said NHGRI Director Francis S. Collins, M.D., Ph.D. "As we build upon the foundation laid by the Human Genome Project, it’s become clear that comparing the human genome with the genomes of other organisms is an enormously powerful tool for understanding our own biology." The chimp sequence draft represents the first non-human primate genome and the fourth mammalian genome described in a major scientific publication. A draft of the human genome sequence was published in February 2001, a draft of the mouse genome sequence was published in December 2002 and a draft of the rat sequence was published in March 2004. The essentially complete human sequence was published in October 2004.

Keyword: Genes & Behavior; Evolution
Link ID: 7825 - Posted: 06.24.2010

By Robert C. Cowen When an inert placebo acts like a drug, is it just a psychological illusion? Or is it a real biological effect? Research reported last week suggests that it's both. The mere belief that they had received a pain killer was enough to release the brain's natural painkilling endorphins in the patients tested, scientists say. This opens a new line of research into the placebo puzzle. The effect has been demonstrated often enough to show that some patients appear to benefit from such belief. But there hasn't been enough evidence to convince skeptics that anything more than the so-called power of suggestion is at work. That's changing. "The findings of this study are counter to the common thought that the placebo effect is purely psychological due to suggestion and that it does not represent a real physical change." says University of Michigan neuroscientist Jon-Kar Zubieta. He is principal author of the study published Aug. 24 in The Journal of Neuroscience. Some mind/body effects are well known. Adrenaline flows when firefighters go into action. The sight of a lion induces physical changes that prepare a zebra to flee. Humans often experience a similar fight-or-flight reaction to a perceived threat. But it's been too much of a stretch for many neuroscientists to accept that belief in fake medication can produce medical benefits that can be objectively verified. Copyright © 2005 The Christian Science Monitor.

Keyword: Pain & Touch
Link ID: 7824 - Posted: 06.24.2010

By Jonathan Picker, Ph.D. Schizophrenia appears to be a disorder of development that results from a series of neurological insults from fetal life onward (Rapoport et al., 2005). Whether or not schizophrenia manifests appears to be the result of a conglomeration of these factors, both genetic and environmental in origin (Sullivan et al., 2003), as shown in the Figure. No one factor appears to be most significant in the genesis of schizophrenia. This is evident despite the very significant resources that have been expended in the search to understand the patho-etiology of schizophrenia. This may be because there are multiple factors involved; multiple different disorders with varied pathologies present with the schizophrenia phenotype; or a combination of both. The search to uncover the pathological basis to schizophrenia has, however, provided broad generalizations that have yielded more specific etiological candidates as a result of newer, more powerful methodologies, particularly those resulting from the Human Genome Project. Interestingly, some of the genetic candidates identified providing explanatory models that may incorporate identified environmental risk factors. Risk for schizophrenia appears to begin as early as the first trimester in pregnancy, with exposure to influenza associated with increased risk of later developing schizophrenia (Brown et al., 2004). Other prenatal factors are also implicated in the second and third trimesters. © 2005 Psychiatric Times. All rights reserved.

Keyword: Schizophrenia
Link ID: 7823 - Posted: 06.24.2010

By Stephen V. Faraone, Ph.D., and Philip Asherson, MRCPsych, Ph.D. Although attention-deficit/hyperactivity disorder is frequently misunderstood as caused by normal childhood energy, boring classrooms, or overstressed parents and teachers, several decades of research show ADHD to be a valid disorder with a neurobiological basis (Faraone, in press). Genetic studies have played a leading role in clarifying the biological basis of the disorder. Family studies have documented familial transmission; adoption studies show this transmission occurs through biological, not adoptive relationships; and twin studies show that ADHD is highly heritable such that genes account for about 75% of the disorder's variability in the population (Faraone et al., in press). With a prevalence of 8% to 12% (Faraone et al., 2003), it is among the most common of psychiatric disorders. Given this strong evidence from epidemiologic studies, molecular genetic studies have begun the search for genes that increase susceptibility to ADHD. Two general approaches have been used. Genome scan linkage studies scan the entire genome in search of regions that might harbor susceptibility genes. They do not require a prior hypothesis about which genes cause the disorder. In contrast, candidate gene studies nominate specific genes based on a biological theory about their putative role. They use the method of association to test these prior hypotheses. © 2005 Psychiatric Times. All rights reserved.

Keyword: ADHD; Genes & Behavior
Link ID: 7822 - Posted: 06.24.2010

DALLAS – – Vagus nerve stimulation (VNS) therapy, a treatment recently approved by the Food and Drug Administration for treatment-resistant depression, produced a positive response in more than 25 percent of patients in a national, yearlong study led by UT Southwestern Medical Center psychiatrists. Sixteen percent to 20 percent of the study group experienced total remission. Results of the study, led by Dr. A. John Rush, vice chairman for research in psychiatry at UT Southwestern, appear in the September issue of Biological Psychiatry. Findings from two additional related studies also are included in the issue. VNS therapy, which the FDA approved for treatment of epileptic seizures in 1997 and for depression in July, has been studied in clinical trials for treatment-resistant depression since 1998. VNS therapy includes surgical implantation of a small battery-operated pulse generator – similar to a pacemaker – in a patient's left upper chest. Thin, flexible wires from the device are tunneled into the neck and send mild, intermittent pulses to the neck's left vagus nerve. The vagus nerve in turn delivers these pulses about every five minutes to the areas of the brain involved in the regulation of mood, motivation, sleep, appetite and other symptoms relevant to depression.

Keyword: Depression
Link ID: 7821 - Posted: 06.24.2010