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February 27, 2007, 7:38 PM CT
Association Between Gene And Intelligence
A team of scientists, led by psychiatric geneticists at Washington University School of Medicine in St. Louis, has gathered the most extensive evidence to date that a gene that activates signaling pathways in the brain influences one kind of intelligence. They have confirmed a link between the gene, CHRM2, and performance IQ, which involves a person's ability to organize things logically.
"This is not a gene for intelligence," says Danielle M. Dick, Ph.D., assistant professor of psychiatry and lead author on the study. "It's a gene that's involved in some kinds of brain processing, and specific alterations in the gene appear to influence IQ. But this single gene isn't going to be the difference between whether a person is a genius or has below-average intelligence."
Dick's team comprehensively studied the DNA along the gene and observed that several variations within the CHRM2 gene could be correlated with slight differences in performance IQ scores, which measure a person's visual-motor coordination, logical and sequential reasoning, spatial perception and abstract problem solving skills. When people had more than one positive variation in the gene, the improvements in performance IQ were cumulative. The study's findings are available online in Behavioral Genetics and will appear in an upcoming print issue of that journal.........
Posted by: Daniel Read more Source
February 26, 2007, 8:51 PM CT
Menstrual Cycle And The Female Brain
What influence does the variation in estrogen level have on the activation of the female brain? Using functional Magnetic Resonance Imaging, Jean-Claude Dreher, a researcher at the Cognitive Neuroscience Center (CNRS/Universit Lyon 1), in collaboration with an American team from the National Institute of Mental Health (Bethesda, Maryland) directed by Karen Berman, has identified, for the first time, the neural networks involved in processing reward-related functions modulated by female gonadal steroid hormones. This result, which was published online on January 29, 2007 on the PNAS website, is an important step in better comprehension of certain psychiatric and neurological pathologies.
The human brain has a recompense system that predicts different types of reward (food, money, drugs). The normal functioning of this system plays a fundamental role in a number of cognitive processes such as motivation and learning. This reward system, composed of dopaminergic neurons1 situated in the mesencephalon (a very deep region of the brain) and their projection sites2, is crucial for neural coding of rewards. Its dysfunction can result in disorders such as addictions and is also implicated in various psychiatric and neurological pathologies, such as Parkinson's disease and schizophrenic disorders. A number of studies on animals prove that the dopaminergic3 system is sensitive to gonadal steroid hormones (estrogen, progesterone). For example, female rats self-administer cocaine (a drug that acts on the dopamine system) in higher doses after estrogens have been administered to them. The influence of gonadal steroid hormones on the activation of the reward system remained to be studied in humans. A better knowledge of this influence should make for better understanding of the differences between men and women, especially as observed in the prevalence of certain psychiatric pathologies and in vulnerability to drugs, (for which the dopaminergic system plays an important role.) It is known, for example, that the female response to cocaine is greater in the follicular phase of the menstrual cycle4 than in the luteal phase5.Moreover, schizophrenia tends to appear later in women than in men.........
Posted by: Emily Read more Source
February 26, 2007, 8:49 PM CT
Creating New Life Forms to fight cancer
Instead of using the usual cancer-fighting modalities, surgery, chemotherapy, or radiation, researchers from a drug development company called Advaxis, have embarked on a novel approach to fighting cancer: Engaging the immune system to attack cancer in the same the way it would a flu vaccine, by creating new life forms.
Dr. Vafa Shahabi, Advaxis' Director of Research and Development, reports that because the human immune system is not designed to fight cancer on its own, she and her colleagues are trying to harness its power through a new kind of life form: specifically a family of vaccines, which they call Lovaxin. The vaccines are comprised of new strains of bacteria created in Advaxis' laboratory that are programmed to kill off specific cancers.
The Key: A Microbe Found in Dairy Products Central to this startling discovery is the microbe Listeria monocytogenes, a common bacterium found in milk, cheese and other dairy products. This microorganism apparently aids in fighting cancer by activating the body's own killer (cytotoxic T) cells to elicit a stronger than normal immune response to the presence of cancer cells. The vaccines "teach" the immune system to mount a specialized, targeted response that is lethal to cancer.
When Listeria is introduced in the body, it has a powerful, direct stimulatory effect on the activities of tumor-killing T cells. "Essentially the modified Listeria vaccines harness the power of the immune system against this infectious agent," explains Dr. Shabahi, "and then directs it to successfully attack cancer cells. The bacterium in effect then becomes a cancer-fighting 'Trojan horse,' with the enemy tucked inside."........
Posted by: Janet Read more Source
February 26, 2007, 8:04 PM CT
Circadian Rhythm In Swim Performance
A new study investigating the potential of a circadian rhythm in athletic performance adds further confirmation that it exists. The finding is being reported in the Journal of Applied Physiology, one of 11 peer evaluated scientific publications issued monthly by the American Physiological Society (APS) (www.The-APS.org). The authors of "Circadian Variation in Swim Performance," are Christopher E. Kline, J. Larry Durstine, J. Mark Davis, Teresa A. Moore, Tina M. Devlin, Mark R. Zielinski, and Shawn D. Youngstedt, all from the Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC. .
Circadian rhythms are generated within the body, and are "re-set" almost every 24 hours. Human circadian rhythms originate from the tiny hypothalamus residing in the back of the brain. The hypothalamus, working with the endocrine system, drives a number of of our behavioral and physiological rhythms.
Scientists have speculated that there may be a circadian rhythm inherent in athletic performance and point to research showing that athletic performance varies based on time-of-day. Other studies have shown that peak performance occurs in early evening, at approximately the peak of the body temperature rhythm. Additional studies have observed that morning is the worst time for athletic performance.........
Posted by: Scott Read more Source
February 26, 2007, 8:00 PM CT
Antidepressants to decrease alcohol consumption
CIHR-funded study explored the relationship between use of antidepressants and level of alcohol consumption, examining whether using antidepressants affected the link between depression and level of alcohol consumption. The research conducted by the Centre for Addiction and Mental Health (CAMH) concluded that women suffering from depression consumed more alcohol than women who did not experience depression, regardless of antidepressant use. This finding differs significantly from rates found in male counterparts. While men suffering from depression generally consume more alcohol than non-depressed men, those who use antidepressants consume alcohol at about the same level as non-depressed men.
Dr. Kathryn Graham, Senior Scientist with CAMH and Agnes Massak, Ph.D student in the Department of Psychology at the University of Western Ontario, published the study in the Canadian Medical Association Journal (CMAJ) on February 27, 2007.
"Our results agree with prior clinical research that suggests that the use of antidepressants is linked to lower alcohol consumption among men suffering from depression," said Dr. Graham. "But this does not appear to be true for women".
Overall, participants in the survey experiencing depression (both men and women) drank more alcohol than did non-depressed respondents. However, men taking antidepressants consumed significantly less alcohol than depressed men who did not use antidepressants. Non-depressed men consumed 436 drinks per year, in comparison to 579 drinks for depressed men not using antidepressants, and 414 drinks for depressed men who used antidepressants.........
Posted by: JoAnn Read more Source
February 26, 2007, 7:52 PM CT
The metabolic response to colitis
A new study being published by the American Physiological Society (www.The-APS.org) finds that the body responds differently to colitis (inflammation of the colon) based on whether the disease is acute (sharp and brief) or chronic (long-term). Researchers, using an experimental mouse model of colitis, discovered that the effects of acute colitis were linked to decreased body weight, food intake, and body fat content. Chronic colitis was linked to reduced body fat content, decreased bone mineral density and attenuated use of energy, termed energy expenditure. The discovery may help lead to better symptom management for the 500,000 Americans who live with the disease.
The study, "Mice With Experimental Colitis Show an Altered Metabolism With Decreased Metabolic Rate, " was conducted by Silvia Melgar and Erik Michalsson, Integrative Pharmacology, GI Biology, AstraZeneca; Lennart Svensson, Department of Molecular Pharmacology, AstraZeneca; Anna-Karin Gerdin and Mohammad Bohlooly-Y, AstraZeneca Transgenics and Comparative Genomics Centre, AstraZeneca, Molndal, Sweden; and Mikael Bjursell, Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, Goteborg University, Sweden and AstraZeneca Transgenics and Comparative Genomics Centre, AstraZeneca, Molndal, Sweden. Their study appears in the Articles in Press Section of the American Journal of Physiology, Gastrointestinal and Liver Physiology. The journal is one of 11 peer evaluated scientific publications issued each month by the American Physiological Society (APS).........
Posted by: Sue Read more Source
February 26, 2007, 6:27 PM CT
Avoiding Carpal Tunnel Syndrome
In work involving the hands, whether using a computer or a hammer, the wrist is a vulnerable spot. Repeated or sustained bending and flexing can lead to carpal tunnel syndrome (CTS).
A group of human factors/ergonomics (HF/E) scientists from the University of California at San Francisco and McMaster University in Ontario, Canada, have conducted the first study that systematically identifies how one contributor to CTS carpal tunnel pressure can be examined in detail to establish limits on how much a wrist can be flexed before nerve damage sets in. The scientists believe their findings could be used to create simple guidelines to help workers avoid wrist postures that are likely to cause nerve trauma. The findings from their study appear in a paper in the recent issue of Human Factors: The Journal of the Human Factors and Ergonomics Society.
The research team studied the pressure that is placed on the nerve in the carpal tunnel in various wrist postures in 37 healthy men and women between the ages of 22 and 50. Wrist postures that are not neutral (that is, bent or flexed) cause increased pressure on the nerve. The scientists concluded that when sustained pressure on the carpal tunnel reaches 30 mmHG, injury is likely to occur.
In order to keep pressure below 30 mmHG, it is recommended that sustained wrist extension (bending the hand back) should not exceed 32.7 degrees, wrist flexion (bending the wrist toward the palm) should not exceed 48.6 degrees, ulnar deviation (sideways toward the small finger) should not exceed 14.5 degrees, and radial deviation (sideways toward the thumb) should not exceed 21.8 degrees.........
Posted by: Mark Read more Source
February 24, 2007, 9:05 PM CT
Irregular Heartbeat Linked To Genetic Mutation
Every day for 10 years, a seemingly heart-healthy 53-year-old woman experienced rapid and irregular heartbeats. She had no personal or family history of high blood pressure or hyperthyroidism. She did not suffer from myocardial or coronary artery disease, or any abnormalities of the heart as best doctors and medical science could determine. Yet, she complained of heart palpitations and dizziness nearly to the point of fainting.
For the patient in this case study, her symptoms first appeared 10 years ago and they persisted through the years. The symptoms peaked in the morning and occurred more frequently as time went on. Doctors prescribed medication, but it proved to be ineffective.
As a next step, Mayo Clinic doctor scientists explored and confirmed the presence of a genetic mutation that clearly established an inherited predisposition to atrial fibrillation.
Their study findings appear in the February issue of Nature Clinical Practice Cardiovascular Medicine http://www.nature.com/clinicalpractice/cardio.
"Why certain patients develop atrial fibrillation while others do not, despite comparable environmental stress exposure, might ultimately depend on their genetic makeup," the authors write.
Atrial fibrillation is recognized more often in the elderly who have underlying structural heart disease. But in this study, Mayo Clinic scientists address the gene-based form of atrial fibrillation that affects younger people who do not otherwise harbor risk factors for the disease. The case was in comparison to 2,000 individuals who did not carry the mutation or suffer from atrial fibrillation.........
Posted by: Daniel Read more Source
February 24, 2007, 8:51 PM CT
Kids allowed to join groups for complex reasons
New research at the University of Maryland looks at why kids decide to include - and exclude - other kids from their group of friends. It turns out the decision making process is much more complex than previously believed, and could even provide insights into how to intervene when children are rejected by their peers.
Human Development Professor Melanie Killen (College of Education) led the 4-year project, which was recently reported in the February, 2007 edition of Current Directions in Psychological Science (Association for Psychological Science).
Killen, who is the associate director of the Center for Children, Relationships, and Culture at Maryland says the decision making process includes many factors. "They take into account group information, ranging from cliques and networks, when deciding what makes a group work well. Sometimes kids are excluded because they lack social skills, but a lot of time it has nothing to do with that. Instead it has to do with what we refer to as 'group membership' such as gender, race, ethnicity, and culture."
Whatever the reason, earlier research has shown that individuals who experience pervasive long-term exclusion suffer from depression, anxiety and loneliness.
Killen's research looked at two models when trying to define how children make decisions about including - or excluding - other children from their group. One model - called the "individual social deficit model" says that rejection occurs due to a child's social deficits - including being shy, wary or fearful. In contrast, the "intergroup social cognition model" says that rejection happens due to things like group dynamics, bias, prejudice and inclusion/exclusion.........
Posted by: JoAnn Read more Source
February 24, 2007, 8:40 PM CT
Symbicortand Improves Lung Function
Wilmington, DE February 24, 2007 New data demonstrated the maintenance combination asthma treatment, SYMBICORT (budesonide/formoterol fumarate dehydrate), provides a rapid, clinically significant bronchodilatory response, or opening of the airways, defined as the median time to achieve ≥15% improvement in lung function within 15 minutes after administration. In addition, these data demonstrated that compared to its monocomponents (budesonide and formoterol) and placebo, SYMBICORT and the other therapy groups containing formoterol had a faster bronchodilatory response than budesonide or placebo. The combined study results, involving patients with mild-to-severe persistent asthma who previously mandatory therapy with inhaled corticosteroids (ICS), were presented today at the annual meeting of the American Academy of Allergy, Asthma and Immunology (AAAAI) held in San Diego, February 23-27, 2007.
SYMBICORT is a newly approved, twice-daily, inhaled combination treatment containing budesonide, a corticosteroid, and formoterol, a rapid and long-acting beta2-agonist. It is indicated for the long-term maintenance therapy of asthma in patients ages 12 and older. SYMBICORT is not indicated in patients whose asthma can be successfully managed by inhaled corticosteroids along with occasional use of inhaled, short-acting beta2-agonists.........
Posted by: JoAnn Read more Source
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Did you know?
Studies in monkeys and women suggest that unlike traditional estrogen therapy, a diet high in the natural plant estrogens found in soy does not increase the risk of uterine cancer in postmenopausal women, according to Mark Cline, D.V.M., Ph.D., an associate professor of comparative medicine at Wake Forest University Baptist Medical Center.
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