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By Susan Freinkel The brain and other complex mechanisms of the human nervous system rely on 40 or so basic nutrients to run smoothly. The lack of any one—be it zinc or magnesium, chromium or folic acid—can cause a malfunction, leading to depression, irritability, or worse. When pigs are penned in close quarters, some become so irritable they savage their pen mates’ ears and tails, a problem farmers call ear-and-tail-biting syndrome. David Hardy, a Canadian hog-feed salesman from the farmlands of southern Alberta, knew that behavior well. Years of experience had taught him something else: All it takes to calm disturbed pigs down is a good dose of vitamins and minerals in their feed. That came to Hardy’s mind one November evening in 1995 when an acquaintance, Tony Stephan, began confiding his troubles. His wife, Deborah, had killed herself the year before after struggling with manic depression and losing her father to suicide. Now two of his 10 children seemed headed down the same road: Twenty-two-year-old Autumn was in a psychiatric hospital and 15-year-old Joseph had become angry and aggressive. He had been diagnosed as bipolar, a term for manic depression, but even with medication he was prone to outbursts so violent that the rest of the family feared for their lives. The boy’s irritability sounded familiar to Hardy. I don’t know a whole lot about mental illness, Hardy told Stephan, but I’ve seen similar behavior in the hog barn, and it’s easy to cure. © 2004 The Walt Disney Company
Keyword: Depression; Aggression
Link ID: 7197 - Posted: 06.24.2010
Delinquency, violence, and/or drug abuse are known to be influenced by the way that psychosocial, situational, and hereditary factors interact. Only recently have researchers begun to examine the effects that specific genotypes and psychosocial factors may have on behavior. A study in the April issue of Alcoholism: Clinical & Experimental Research looks at what impact interactions between a polymorphism of the serotonin transporter (5-HTT) gene and family relations may have on adolescent drinking. "Hereditary factors can explain quite a lot of the variance in alcohol consumption," said Kent W. Nilsson, a researcher at the Centre for Clinical Research at Uppsala University in Sweden and corresponding author for the study. "Likewise, environmental factors can have a fairly high impact on alcohol consumption. In addition, other studies have shown that hereditary risks may be amplified in an unfavourable environment, and that different, and sometimes contradicting, results of gene associations may be explained by different environmental/background factors of the study participants." "Most complex behavioral disorders such as alcoholism have a heritability in the range of 40 to 60 percent, so we know there must be an important influence of life experience as well, and potential for interactions," said Markus Heilig, clinical director of the National Institute on Alcohol Abuse and Alcoholism. "The problem is that these disorders are also polygenic. That means that each specific locus is only likely to contribute a small component of disease risk, a few percent at best. That in itself is hard enough to find unless studies are very large. Finding the interaction of course is even more challenging."
Keyword: Drug Abuse; Genes & Behavior
Link ID: 7196 - Posted: 04.15.2005
CHAMPAIGN, IL. -- According to conventional wisdom, babies don't begin to develop sophisticated psychological reasoning about people until they are about 4 years old. A study of 15-month-olds at the University of Illinois at Urbana-Champaign proves otherwise. The findings, published in the April 8 issue of the journal Science, potentially could lead to an early screening tool for autism, a developmental disability that is marked by a failure on false-belief and related tasks, the researchers say. In a non-verbal experiment, each participating baby, 56 in all, sat on a parent's lap and faced an actor (a university student). On the table between the baby and the actor was a toy watermelon slice and two boxes whose openings faced each other; one box was green, the other yellow. To start, the actor picked up the watermelon slice, played with it, and then hid it in the green box. On subsequent trials, the actor always reached into the green box, as though to grasp the watermelon slice she had hidden there. Then, seemingly unbeknownst to the actor but in sight of the infant, the watermelon slice moved to the yellow box.
Keyword: Development of the Brain
Link ID: 7195 - Posted: 04.15.2005
Roxanne Khamsi Women who have had both their ovaries removed are at double the normal risk of developing Parkinson's disease, according to a study of medical records stretching back half a century. But experts stress that ovary removal - or ovariectomy - can in many cases save lives. Women's ovaries produce significant amounts of the hormone oestrogen, which has been shown to protect certain types of nerve cell. "It acts on cells to make them less susceptible to toxins," says Kieran Breen, director of research at the Parkinson's Disease Society in London. He adds that this may happen because the hormone activates certain genes that produce protective proteins. The nerve cells that oestrogen seems to help include those in the substantia nigra, an area deep in the brain that controls voluntary movements. Patients with Parkinson's disease show degeneration in this region, leading to the disease's characteristic shaking and unsteadiness, explains neurologist Walter Rocca of the Mayo Clinic College of Medicine in Rochester, Minnesota. Rocca and his colleagues wanted to understand how surgical removal of the ovaries influences a woman's chance of developing Parkinson's disease or its symptoms. To do this, they searched medical records from 1950 to 1987 from Olmstead County in Minnesota, which had a linkage system that consolidated each person's medical files in a single dossier. ©2005 Nature Publishing Group
Keyword: Parkinsons; Hormones & Behavior
Link ID: 7194 - Posted: 06.24.2010
Execution by lethal injection may not be the painless procedure most Americans assume, say researchers from Florida and Virginia. They examined post-mortem blood levels of anaesthetic and believe that prisoners may have been capable of feeling pain in almost 90% of cases and may have actually been conscious when they were put to death in over 40% of cases. Since 1976, when the death penalty was reinstated in the US, 788 people have been killed by lethal injection. The procedure typically involves the injection of three substances: first, sodium thiopental to induce anaesthesia, followed by pancuronium bromide to relax muscles, and finally potassium chloride to stop the heart. But doctors and nurses are prohibited by healthcare professionals’ ethical guidelines from participating in or assisting with executions, and the technicians involved have no specific training in administering anaesthetics. “My impression is that lethal injection as practiced in the US now is no more humane than the gas chamber or electrocution, which have both been deemed inhumane,” says Leonidas Koniaris, a surgeon in Miami and one of the authors on the paper. He is not, he told New Scientist, against the death penalty per se. But Kyle Janek, a Texas senator and anaesthesiologist, and a vocal advocate of the death penalty, insists that levels of anaesthetic are more than adequate. He says that an inmate will typically receive up to 3 grams - about 10 times the amount given before surgery. “I can attest with all medical certainty that anyone receiving that massive dose will be under anaesthesia,” he said in a recent editorial. © Copyright Reed Business Information Ltd.
Keyword: Pain & Touch
Link ID: 7193 - Posted: 06.24.2010
A PIONEERING treatment has allowed paralysed dogs to regain some movement. The results have raised hopes that the method will work in people too. So far, nine dogs paralysed in road accidents or by spinal disc injuries have been treated by veterinary surgeons Robin Franklin and Nick Jeffery of the University of Cambridge. Within a month, all regained the ability to make jerky movements in their hind legs, Jeffery told a meeting in Birmingham, UK, this week, although they are only slowly gaining the ability to support their own weight. Many different approaches to treating spinal injuries are being explored, but promising results in small animals such as rats have often not been repeated in larger animals. That is one of the reasons why the dog results are exciting, says Geoffrey Raisman of the Institute of Neurology at University College London, one of the pioneers of the method used by the Cambridge team. "I think that these findings in dogs are directly relevant to the human situation," he says. "Of course, we canšt know for sure without doing the work but it is a very good indicator that we can expect the same effects. We are hoping to start similar trials in humans within a couple of years." In Australia, three patients have already been treated using the same method (New Scientist, 12 July 2002, p 18). But the results will not be revealed until 2007. © Copyright Reed Business Information Ltd.
Keyword: Regeneration
Link ID: 7192 - Posted: 06.24.2010
By STEPHANIE PACE A UC Berkeley psychology researcher is experimenting with inbred mouse strains to forage for insight into how genes affect behavioral traits and emotionality. The research shows that prenatal and postnatal environments are also useful in determining adult behavior in mice. “Why are some people highly responsive and highly reactive to stress? Why are some people calm and mellow?” said Darlene Francis, a professor in the School of Public Health and a researcher in the Helen Wills Neuroscience Institute. Francis claims that it is more likely that the development of behavioral traits result more from environmental factors during development rather than from genetic differences between offspring. “We’re using rat and mice models as mathematical approaches to research and as an alternative system to ask questions we can’t ask in people,” Francis said. According to Francis, the mechanisms of gene regulation are similar among rats, mice and humans. Though there are critical variables in humans that are different from rat and mice models, the mechanism by which genes are regulated are the same, Francis said. To investigate the biological basis of stress responses and differences in stress levels, Francis works with animal models to design experiments that cannot be duplicated in the real world. (c) 2005
Keyword: Stress; Genes & Behavior
Link ID: 7191 - Posted: 06.24.2010
A treatment that has helped paralysed dogs to move could also help people, researchers have claimed. Veterinary surgeons from the University of Cambridge have treated nine dogs, who were all able to move their hind leg jerkily, within a month. The treatment takes nerve cells from the brain and injects them into the damaged part of the spinal cord. An expert from the Institute of Neurology said he believed the same benefits could be seen in humans. An Australian team has already treated humans with OEG cells, but the results will not be published until 2007. The UK researchers studied dogs which had been paralysed in road accidents, or through spinal cord injuries. All had been unable to move for at least three months. The treatment uses olfactory ensheathing glia (OEG) cells, which are present at the back of the nose. They are the only nerve cells capable of constant regeneration. The cells were collected by opening the dogs' skulls. They were then multiplied in the lab, and injected into the spinal cord. In addition to regaining some movement, the animals also appeared to recover some sensation below the injury site. Three can now warn their owners if they need to empty their bladder, although they have not regained control. The researchers say there is no indication the dogs can feel pain again but, by the same token, they do not appear to be suffering pain from a severed nerve - a potential side effect of the treatment. (C)BBC
Keyword: Regeneration
Link ID: 7190 - Posted: 04.14.2005
By GINA KOLATA After years of telling athletes to drink as much liquid as possible to avoid dehydration, some doctors are now saying that drinking too much during intense exercise poses a far greater health risk. An increasing number of athletes - marathon runners, triathletes and even hikers in the Grand Canyon - are severely diluting their blood by drinking too much water or too many sports drinks, with some falling gravely ill and even dying, the doctors say. New research on runners in the Boston Marathon, published today in The New England Journal of Medicine, confirms the problem and shows how serious it is. The research involved 488 runners in the 2002 marathon. The runners gave blood samples before and after the race. While most were fine, 13 percent of them - or 62 - drank so much that they had hyponatremia, or abnormally low blood sodium levels. Three had levels so low that they were in danger of dying. The runners who developed the problem tended to be slower, taking more than four hours to finish the course. That gave them plenty of time to drink copious amounts of liquid. And drink they did, an average of three liters, or about 13 cups of water or of a sports drink, so much that they actually gained weight during the race. Copyright 2005 The New York Times Company
Keyword: Miscellaneous
Link ID: 7189 - Posted: 04.14.2005
In 2001, a massive stroke left Pete Cornelis all but paralyzed – robbing him of his passion for painting, as well as everyday things like walking and eating. "The only thing I could move on my entire body was my two fingers," he recalls. But thanks to his treatment at The Neurological Institute of New York, part of Columbia University Medical Center, followed by years of hard work, perseverance and extensive physical therapy, Cornelis managed to regain almost all of his lost movement. "I was surprised by how much I had to relearn," he ays. But, "it is absolutely possible to retrain you brain, to re-wire it, and have it learn what the old [damaged brain] parts used to do." His brain had to slowly work to compensate for the areas of his brain that were basically dead and could not be revived. When a stroke occurs, blood flow to part of the brain is interrupted when a blood vessel becomes damaged or blocked. The blood normally brings oxygen and nutrients that the brain cells in the immediate area need to survive. Without the blood the brain cells begin to die and stroke victims lose the functions that were controlled by those brain cells. About 80% of all strokes are ischemic, caused by a blood clot that blocks a blood vessel or artery in the brain. The other 20% are caused by a weakened blood vessel that breaks and bleeds into the brain. This is known as hemorrhagic stroke, and is often fatal. Around 600,000 new strokes, or "brain attacks" are reported each year. (C) ScienCentral, 2000-2005.
Keyword: Stroke; Regeneration
Link ID: 7188 - Posted: 06.24.2010
Two widely used treatments for Alzheimer's disease may not be as effective as previously thought, say researchers at the Mayo Clinic in Rochester, Minnesota. The findings, reported online today in the New England Journal of Medicine suggest that vitamin E does not slow a patient's slide from symptoms of memory loss to Alzheimer's, while benefits from the popular drug donepezil are limited to the first year of treatment. Neurodegenerative diseases such as Alzheimer's are usually preceded by a fuzzy state between memory loss and dementia, known as mild cognitive impairment. Since most treatments are better at preserving nerve function than restoring it, patients likely to get Alzheimer's are typically treated with drugs that slow nerve degeneration. In recent years, donepezil and vitamin E have become the drugs of choice. That’s because studies have shown donepezil raises levels of a neurotransmitter needed for memory and learning, while vitamin E is an antioxidant that could repair damage to soft tissue from free reactive oxygen – one of the causes of Alzheimer’s. Vitamin E is even used widely as a preventive measure by people with normal brain function. Ronald C. Petersen and his colleagues at the Mayo Clinic evaluated these two compounds with clinical tests of more than 700 people likely to develop Alzheimer's. For 3 years patients were given varying doses of vitamin E and donepezil. Detailed psychological tests on the patients to measure their mental abilities showed a surprising result: Vitamin E did nothing to prevent Alzheimer's. At the end of 12 months, 38 patients in the placebo group had Alzheimer's compared to 33 from the vitamin E group. Meanwhile, only 16 patients who took donepezil got Alzheimer’s. The drug was only effective for a short time, however. At the end of 3 years, the number of Alzheimer’s patients in all three groups did not vary significantly. Copyright © 2005 by the American Association for the Advancement of Science.
Keyword: Alzheimers
Link ID: 7187 - Posted: 06.24.2010
Interpreting the cadences of human speech requires that information be transmitted from the ear to the brain with exquisitely precise timing. Neurons in general are no slackers at transmitting signals, but specialized neurons in the ear known as inner hair cells perform at an even higher level. Two papers published this week offer insights into how these cells respond so speedily. Neurons store neurotransmitters, molecules that serve as the bits and bytes of communication, within small membrane-bound compartments called synaptic vesicles. Upon stimulation, the vesicles fuse with the outer membrane of the neuron and release neurotransmitters that excite the next neuron in line. During signaling, neurons need to constantly replenish their supply of vesicles. Most neurons make new vesicles using bits of recycled cell membrane, a relatively slow process. In a study published online in Nature today, physiologist Claudius Griesinger of University College London and colleagues show that hair cells rev up this process by making vesicles from scratch and storing them in the cytoplasm, instead of culling them from the membrane. The preformed vesicles are then shipped to the presynaptic ribbon, a structure that organizes vesicles near the site of their release. This difference helps maintain a seemingly inexhaustible supply of vesicles while sustaining a vesicle release rate 100 times higher than that of a conventional neuron, say the researchers. Another paper in Nature, by Tobias Moser of the University of Goettingen, Germany, and colleagues, suggests that ribbons enable the release of multiple vesicles in parallel during the initial burst of signaling by a stimulated hair cell. Copyright © 2005 by the American Association for the Advancement of Science.
Keyword: Hearing
Link ID: 7186 - Posted: 06.24.2010
In a study of people with mild cognitive impairment (MCI), those who took the drug donepezil were at reduced risk of progressing to a diagnosis of Alzheimer’s disease (AD) during the first year of the trial, but by the end of the 3-year study there was no benefit from the drug. Vitamin E was also tested in the study and was found to have no effect at any time point in the study when compared with placebo. These findings, from the Memory Impairment Study, are the first to suggest than any agent can delay the clinical diagnosis of AD in people with MCI. The effects of the drug measured in this study “did not provide support for a clear recommendation for the use of donepezil” generally to forestall the diagnosis of AD in people with MCI, the researchers stated in their report, but they did note the potential importance of the findings for some patients. The data, they said, “could prompt a discussion” between clinicians and patients on the possibility of donepezil therapy in certain cases. The findings were reported in the April 14, 2005, online The New England Journal of Medicine by principal investigators Ronald Petersen, Ph.D., M.D., of the Mayo Clinic, Rochester, MN, Leon Thal, M.D., of the University of California, San Diego, and colleagues. The research was funded in part by the National Institute on Aging (NIA) and was conducted as part of the Alzheimer’s Disease Cooperative Study (ADCS), a nationwide clinical trials consortium supported by the NIA, a component of the National Institutes of Health, U.S. Department of Health and Human Services.
Keyword: Alzheimers
Link ID: 7185 - Posted: 06.24.2010
ARE you a real grump in the mornings? Do you wake up every day feeling tired, embittered, aggrieved, and all too ready to hit the snooze button? If so, then a new alarm clock could be just for you. The clock, called SleepSmart, measures your sleep cycle, and waits for you to be in your lightest phase of sleep before rousing you. Its makers say that should ensure you wake up feeling refreshed every morning. As you sleep you pass through a sequence of sleep states - light sleep, deep sleep and REM sleep - that repeats approximately every 90 minutes. The point in that cycle at which you wake can affect how you feel later, and may even have a greater impact than how long or little you have slept. Being roused during a light phase means you are more likely to wake up perky. SleepSmart records the distinct pattern of brain waves produced during each phase of sleep, via a headband equipped with electrodes and a microprocessor. This measures electrical activity of the wearer's brain, in much the same way as EEG machines used for medical and research purposes, and communicates wirelessly with a clock unit near the bed. You program the clock with the latest time at which you want to be wakened, and it then duly wakes you during the last light sleep phase before that. © Copyright Reed Business Information Ltd.
Keyword: Sleep
Link ID: 7184 - Posted: 06.24.2010
Antioxidant vitamins from fruits and vegetables have exhibited cholesterol-fighting properties and beneficial effects for heart function. Now a new study suggests that they could provide protection from a stroke by limiting the amount of inflicted brain damage. Paula C. Bickford of the University of South Florida College of Medicine and her colleagues worked with four groups of rats that followed different diets over the course of four weeks. The control group ate regular rat chow, while animals in the other groups ate chow supplemented with one of the following foods: blueberries, spinach or spirulina, a type of algae. At the end of the study period, the researchers induced ischemic strokes--in which a blood clot temporarily cuts of the supply of oxygen to the brain--in the animals. The rats in the three experimental groups all had better outcomes than the control rats did. "I was amazed at the extent of neuro-protection these antioxidant-rich diets provided,” Bickford remarks. “The size of the stroke was 50 to 75 percent less in rats treated with diets supplemented with blueberries, spinach or spirulina before the stroke.” © 1996-2005 Scientific American, Inc
Keyword: Stroke
Link ID: 7183 - Posted: 06.24.2010
BEATA ZOLOVSKA When a mother kills her children, how much does mental illness matter when the mother’s guilt is judged in the courtroom? The case of Andrea Yates, who drowned her five children on June 21, 2001, suggests that in some cases the verdict falls before the trial starts. Although abundant evidence exists to prove that Ms. Yates suffered severe mental illness in the 2 years before and at the time of the tragedy, psychosis and delusional hopelessness were not enough for her to be judged not guilty by reason of insanity in court. The case took an unexpected turn recently when the trial court’s verdict was overturned on appeal. Although the appeals court’s reasoning focused on an error by the testifying forensic psychiatrist, it is a reasonable inference that the court’s ruling was based on the assumption that, other things being equal, the jury was at a tipping point. Given the facts presented, for the jury to have been at a tipping point can be understood as a reflection of a folk psychology whereby people are predisposed by the horror of an act itself to use judgmental heuristics. It is thus no wonder that Andrea Yates’s acts are understood more easily as bad rather than mad, regardless of the fact pattern. The puzzling story of Andrea Yates has now received a much needed recounting from journalist Suzanne O’Malley. "Are You There Alone?" is a heartfelt account of the events that led to the tragic deaths of Noah, John, Paul, Luke, and Mary Yates. O’Malley argues that psychosis with manic features, combined with medical mismanagement, stressful circumstances, and religious obsessions masking delusions, resulted in the tragedy. Her reading of the health records presents Andrea Yates’s treatment as a litany of misdiagnoses, poor treatment, wrong medications, and the role of the health insurance company rather than the clinician as the key decision maker in care.
Keyword: Schizophrenia; Aggression
Link ID: 7182 - Posted: 06.24.2010
A breakdown in brain cell communication may contribute to the most common biochemical cause of mental retardation, University of Florida scientists have discovered. The process is akin to a baseball game gone bad. Imagine if a pitcher were joined by six players simultaneously winding up on the mound. Crouched behind home plate, the single catcher would soon be overwhelmed. Even if the coach sent in teammates to catch the extra balls, confusion would reign on the field. UF researchers, writing in the journal Brain, identified an analogous situation in the brains of mice with a version of the hereditary disorder phenylketonuria, or PKU: A flood of an amino acid found in nearly all foods bombards certain brain cells, drowning out their ability to communicate properly and potentially interfering with normal brain development. Scientists have long known that babies born with PKU lack or are deficient in the enzyme that converts the amino acid phenylalanine into a usable form. The amount of the amino acid in the blood builds to toxic levels, ultimately causing severe brain disorders, including mental retardation and seizures. Researchers have been less clear on precisely how that torrent of phenylalanine interferes with brain function. Copyright © 2004 | University of Florida
Keyword: Development of the Brain
Link ID: 7181 - Posted: 06.24.2010
CLEVELAND - - Parents of autistic children can spend as much as $50,000 a year on therapies for their children. But a new research study from Case Western Reserve University's Mandel School of Applied Social Sciences shows promise of providing effective treatment for autism and other developmental disorders at a far lower cost. Gerald Mahoney, the Verna Houck Motto Professor for Families and Communities and co-director of the Center on Intervention for Children and Families at the Mandel School, and Frida Perales, a research associate, conducted a year-long study of the effectiveness of "responsive teaching" strategies for parents to help their autistic children develop and use pivotal developmental behaviors. Responsive teaching strategies promote parent interactions with their children through strategies such as "follow the child's lead" and "take one turn and wait." The results of their study appear in an article in the April 2005 issue of Developmental and Behavioral Pediatrics.
Keyword: Autism
Link ID: 7180 - Posted: 04.13.2005
Surprising results from a nationwide clinical trial show that many children age 7 through 17 with amblyopia (lazy eye) may benefit from treatments that are more commonly used on younger children. Treatment improved the vision of many of the 507 older children with amblyopia studied at 49 eye centers. Previously, eye care professionals often thought that treating amblyopia in older children would be of little benefit. The study results, funded by the National Eye Institute (NEI), part of the National Institutes of Health (NIH), appear in the April issue of Archives of Ophthalmology. “Doctors can now feel confident that traditional treatments for amblyopia will work for many older children, said Paul A. Sieving, M.D., Ph.D., director of the NEI. “This is important because it is estimated that as many as three percent of children in the United States have some degree of vision impairment due to amblyopia. Many of these children do not receive treatment while they are young,” he said. Amblyopia is a leading cause of vision impairment in children and usually begins in infancy or childhood. It is a condition resulting in poor vision in an otherwise healthy eye due to unequal or abnormal visual input while the brain is developing in infancy and childhood. The most common causes of amblyopia are crossed or wandering eye (strabismus) or significant differences between the eyes in refractive error, such as, astigmatism, farsightedness, or nearsightedness.
Keyword: Vision; Development of the Brain
Link ID: 7179 - Posted: 06.24.2010
A possible link between lack of sleep (insomnia) and obesity has been traced to hypocretin/orexin cells in the hypothalamus region of the brain that are easily excited and sensitive to stress, Yale School of Medicine researchers report in the April issue of Cell Metabolism. "If these neurons are over-activated by environmental or mental stress in daily situations, they may support sustained arousal, triggering sleeplessness, leading to overeating," said lead author Tamas Horvath, associate professor in the Departments of Obstetrics, Gynecology & Reproductive Sciences (Ob/Gyn) and Neurobiology at Yale School of Medicine. "The more stress you have, the lower the threshold becomes for exciting these hypocretin neurons." Horvath and co-author Xiao-Bing Gao, assistant professor in Ob/Gyn, studied hypocretin/orexin neurons in mice using electrophysiology and electron microscopy. They found a unique, previously un-described organization of inputs on hypocretin neurons in which excitatory nerve junctions outnumber inhibitory contacts by almost 10 fold. Stressors such as fasting further excite these neurons.