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Cocaine abuse is becoming increasingly prevalent among women of childbearing age, and is associated with numerous adverse perinatal outcomes. New research, published in The Journal of Physiology, by Professor Lubo Zhang and his research team from Loma Linda University School of Medicine in California presents the exciting novel finding that cocaine exposure in utero has lasting and lifelong adverse effects on the heart in adulthood, particularly if you are male! Professor Zhang's research group has been studying the effect of adverse intrauterine environment on fetal heart development and its lifelong pathophysiological consequences in the adult heart. Using an animal model of the pregnant rat, they found that fetal exposure to cocaine during gestation resulted in an increase in heart susceptibility to ischaemia and reperfusion injury in late adult life. Interestingly, the effect of prenatal cocaine exposure on cardiac vulnerability in adult offspring is gender-dependent, with the male heart being more susceptible to increased ischaemia/reperfusion injury induced by prenatal cocaine exposure. Earlier work by professor Zhang's group showed that fetal chronic hypoxia also increased cardiac vulnerability to ischaemia and reperfusion injury in late adult life. Epidemiological studies in humans have shown an association of fetal undernutrition in the womb and an increased risk of hypertension and ischaemic heart disease in adulthood.
Keyword: Drug Abuse; Development of the Brain
Link ID: 7342 - Posted: 05.13.2005
Pamela Fayerman, Pregnant women alert: if you're being plagued by maternal forgetfulness, blame it on your unborn daughters. A new Simon Fraser University study, to be published Thursday in NeuroReport, is the first to show that women carrying male fetuses consistently do better on the hardest memory function tests than women pregnant with girls. "Dumb-mom syndrome" -- as the cognitively compromised state has been jokingly named -- was the focus of an 18-month study by SFU psychology department researchers trying to find out whether pregnancy changed cognition. "We were quite shocked by the results because when we began, we weren't thinking about fetal sex as being a factor," said study co-author Neil Watson, a professor who specializes in neuroscientific research. Watson and co-investigator, PhD candidate Claire Vanston, enrolled 43 Vancouver-area women into the study, subjecting them to a battery of cognition tests from early in their pregnancies to several months after they gave birth. They found that while there was no difference in general intellect between women bearing boys and those with girls, the former group outperformed the latter in tasks involving certain aspects of short-term memory. Watson said in an interview that previous studies have delved into whether attention, concentration and memory are as impaired in pregnancy as anecdotal reports have suggested. But such studies have yielded inconsistent results. Those that did find cognition impacts attributed them to fluctuations in female hormones that steadily increase throughout pregnancy. Copyright © 2005 CanWest Interactive Inc.
Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 7341 - Posted: 06.24.2010
St. Paul, Minn. – People with very mild Alzheimer’s disease are still competent to make decisions about their treatment, while those with moderate Alzheimer’s may no longer be able to competently make those decisions, according to a study published in the May 10 issue of Neurology, the scientific journal of the American Academy of Neurology. The study also found that people who were aware of their Alzheimer’s diagnosis, symptoms, and prognosis were more likely to be able to make competent decisions, regardless of the severity of their disease. “These results are yet another reason why people should consult a doctor if they notice any warning signs of Alzheimer’s in themselves or a loved one,” said study author Jason Karlawish, MD, of the University of Pennsylvania in Philadelphia. “An early diagnosis can help assure that patients can participate in decisions about their care.” For the study, researchers interviewed 48 people with very mild to moderate Alzheimer’s disease and 102 caregivers of people with mild to severe Alzheimer’s. The patients’ decision-making abilities were measured by giving them information about the benefits and risks of a hypothetical treatment for Alzheimer’s and asking them to make a choice whether they would take the treatment. Then experts assessed whether they were competent to make the decision. Of the 48 patients, 19 were found to be competent in making the decision.
Keyword: Alzheimers
Link ID: 7340 - Posted: 06.24.2010
US scientists have invented a pill that can boost memory. The drug CX717 belongs to a family of compounds called ampakines and works by boosting the brain chemical glutamate that makes learning and recall easy. UK trials on 16 sleep-deprived volunteers showed it improved wakefulness and mental ability. Its creator, Dr Gary Lynch from the University of California, told New Scientist it could be used to treat jet lag and diseases like Alzheimer's. Manufacturer Cortex is considering CX717 as a possible treatment for narcolepsy - excessive daytime sleepiness - and attention deficit hyperactivity disorder (ADHD) - a condition which impairs a child's ability to concentrate. It could also be taken by healthy people as a pick-me-up. But it will have to undergo further clinical trials before going on sale. Dr Lynch explained how the drug works. "What it's doing is causing the neurons to communicate with each other a little better. "As you get tired, communication between brain cells begins to fail. When you take the pill, the communication is better." He said the drug appeared to have no side effects and because it was not a physical stimulant, like amphetamines, users would still be able to sleep. In the UK trial, led by Julia Boyle and colleagues from the University of Surrey, healthy male volunteers aged 18 to 45 agreed to test the drug. The volunteers started with a full night's sleep and the following morning and evening were asked to complete a battery of tests assessing memory, attention, alertness, reaction time and problem solving. At 11pm they took either the real or dummy pills and stayed up through the night, being retested at midnight, 1am, 3am, 5am and 9am. (C)BBC
Keyword: Learning & Memory
Link ID: 7339 - Posted: 05.12.2005
By Marc Kaufman Soon after the Food and Drug Administration overruled its advisory panel last year and rejected an application to make an emergency contraceptive more easily available, critics of the agency said it had ignored scientific evidence and yielded to pressure from social conservatives. The agency denied the charge, but an outspoken evangelical conservative doctor on the panel subsequently acknowledged in a previously unreported public sermon that he was asked to write a memo to the FDA commissioner soon after the panel voted 23 to 4 in favor of over-the-counter sales of the contraceptive, called Plan B. He said he believes his memo played a central role in the rejection of that recommendation. The new information comes from a videotaped sermon in October by W. David Hager. On the tape, he said he was asked to write a "minority report" that would outline why over-the-counter sales should be rejected. Speaking at the Asbury College chapel in Wilmore, Ky., Hager said, "I was asked to write a minority opinion that was sent to the commissioner of the FDA. For only the second time in five decades, the FDA did not abide by its advisory committee opinion, and the measure was rejected." © 2005 The Washington Post Company
Keyword: Sexual Behavior
Link ID: 7338 - Posted: 06.24.2010
Radar has helped resolve a long-standing controversy about the purpose of a strange dance performed by bees, Nature magazine reports. The famous "waggle" dance contains information about the whereabouts of nectar, just as was originally proposed in the 1960s, scientists now claim. The theory met with scepticism, partly because people did not believe bees could decode such a complex message. But now radar tracking has proved they do follow waggle dance instructions. Bee-keepers have long puzzled over the mysterious little performance, which bees stage for their hive-mates when they return home from a foraging mission. On entering the hive after gathering nectar, a bee will run around in a tight figure of eight dance, waggling its abdomen as it does so. All the other bees gather around, apparently scrutinising the ceremonial manoeuvre. "It is, at first sight, a rather confusing and not very organised movement," said co-author Joe Riley of Rothamsted Research, UK. "But if you watch it carefully you can recognise the very distinct and organised pattern." It wasn't until the 1960s that a plausible explanation for the dance was proposed, by Nobel Prize winning zoologist Karl von Frisch. He suggested that the bees are delivering a complex set of instructions about how to find a rich nectar source. The direction the bees point while performing the dance, Professor von Frisch speculated, indicates the direction of the food source in relation to the Sun; while the intensity of the waggles indicate how far away it is. (C)BBC
Keyword: Animal Communication; Language
Link ID: 7337 - Posted: 05.12.2005
As far back as the American Civil War doctors have documented cases where patients seemed to experience phantom pains in an uninjured arm or leg after suffering an injury to their opposite limb. While working to understand the biological causes of chronic pain, neurologist Anne Louise Oaklander became curious about these types of phantom pain, having heard surprising complaints from some of her patients. "I had a number of patients who mentioned to me that they had symptoms of injury in the opposite limb, as well as in the injured limb," explains Oaklander, MD, director of the Nerve Injury Unit at Massachusetts General Hospital in Boston. Oaklander's research group has shown that the so-called "mirror-image pain" can't be simply explained away by overuse of the uninjured limb, or as psychological. "These seemingly bizarre complaints have contributed to the impression that some chronic pain patients are crazy," she says. But, studying mirror-image pain in patients suffering from shingles – a condition caused by the virus that produces chicken pox in children, which inflicts adults with a painful rash or blisters on one side of the body – she showed that the answer is even more of a mystery – nerve damage on one side can actually lead to "crossover" nerve damage in the exact same spot on the opposite side of the body. "Many people interpreted our shingles study as due to just the virus getting into the spinal chord and traveling over to the opposite side of the body, and that certainly is a reasonable interpretation, and the most obvious one," Oaklander says. But she had seen this crossover effect in patients with all kinds of injures, such as cut fingers, sprained ankles and broken legs. So she went on to study the mirror-pain related to direct injuries where no viruses were involved. (C) ScienCentral, 2000-2005.
Keyword: Pain & Touch
Link ID: 7336 - Posted: 06.24.2010
An understanding of exactly how the brain controls breathing is fundamental to the treatment of respiratory disorders. We know that breathing is an automatic rhythmic process that persists without conscious effort whether we are awake or asleep, but the question that has intrigued many scientists for well over 100 years is what maintains this almost fail safe vital rhythm throughout life? Experimental Physiology editor Julian Paton invited two world renowned scientists Dr. Guyenet from the University of Charlottesville and Dr. Richerson from Yale University, to use the journal as a forum to discuss the issue and attempt to resolve their differences in opinion. Both authors agree that the respiratory rhythm requires specialised nerve cells (central chemoreceptors) to power the rhythm, but the issue highly debated by Guyenet and Richerson is the precise location and cell types involved. Guyenet proposes that these nerve cells are located in a ventral area of the brainstem (the retrofacial region) and loaded with a transmitter substance called glutamate. Their close proximity to the ventral surface of the brain allows them to sense and react to changes in the pH of the cerebrospinal fluid; this is deemed an essential property of a central chemoreceptor. Richerson, on the other hand, stipulates that central chemoreceptors are found close to the midline blood vessels of the brainstem allowing them to 'taste' the pH of the blood. His cells do not contain glutamate but a substance called serotonin.
Keyword: Miscellaneous
Link ID: 7335 - Posted: 05.12.2005
Michael Hopkin The season in which a woman is born influences the age at which she will go through the menopause, suggests a survey of northern Italians. The survey, which looked at nearly 3,000 post-menopausal women at three clinics, revealed that those born in March showed the earliest menopause, at an average age of 48.9 years. At the other end of the scale, those born in October remained fertile until an average age of 50.3, with many lasting beyond 55. The difference may arise because spring babies tend to be born with a smaller stash of eggs in their ovaries, suggests Angelo Cagnacci of the Modena General Hospital, who led the study. They might therefore run out earlier in life, leading to an earlier menopause. Cagnacci's team quizzed the women on the age at which they entered menopause, and a suite of other factors thought to influence menopause timing: the age at which they first became fertile, whether they ever smoked, their education level and their type of employment. After accounting for these differences, a clear seasonal pattern emerged, the team reports in the journal Human Reproduction1. Previous studies have shown other differences based on time of birth. Babies born in autumn tend to be heavier, for example, and to live longer. ©2005 Nature Publishing Group
Keyword: Biological Rhythms; Sexual Behavior
Link ID: 7334 - Posted: 06.24.2010
By JUDITH GROCH The little old lady with the fine white hair and the sky-blue raincoat was there every day, sitting on a couch in the lobby of our apartment building. I remembered her from the time before her brain began to shred. We'd meet and nod hello in the elevator, but back then I paid no more attention to her than to most of the other tenants who came and went in our busy building. Now you couldn't avoid her. Every morning she would descend from her apartment on the 11th floor to plant herself in her new public sitting room. Day after day we found her there, half inside her head, where chaos was closing in fast; half outside, trying to make sense of the world as it hurried by. "Good morning, dearie," she would say as we emerged from the elevator or returned to the building. We were all "dearies," a label that still survived deep in the tangled cells of her dying brain. Sometimes she would applaud us, clapping as we came and went. Copyright 2005 The New York Times Company
Keyword: Alzheimers
Link ID: 7333 - Posted: 05.11.2005
DURHAM, N.C. -- Monkeys that learn to use their brain signals to control a robotic arm are not just learning to manipulate an external device, Duke University Medical Center neurobiologists have found. Rather, their brain structures are adapting to treat the arm as if it were their own appendage. The finding has profound implications both for understanding the extraordinary adaptability of the primate brain and for the potential clinical success of brain-operated devices to give the handicapped the ability to control their environment, said the researchers. Led by neurobiologist Miguel Nicolelis of Duke's Center for Neuroengineering, the researchers published their findings in the May 11, 2005, issue of the Journal of Neuroscience. Lead author on the paper was Mikhail Lebedev in Nicolelis's laboratory. Other coauthors were Jose Carmena, Joseph O'Doherty, Miriam Zacksenhouse, Craig Henriquez and Jose Principe. The work was supported by the Defense Advanced Research Projects Agency, the James S. McDonnel Foundation, the National Institutes of Health, the National Science Foundation and the Christopher Reeve Paralysis Foundation. In the study, Lebedev performed detailed analysis of the mass of neural data that emerged from experiments reported in 2003, in which the researchers discovered for the first time that monkeys were able to control a robot arm with only their brain signals. © 2001-2005 Duke University Medical Center
Keyword: Robotics
Link ID: 7332 - Posted: 06.24.2010
Nicholas Wade, New York Times Using a brain imaging technique, Swedish researchers have shown that gay and straight men respond differently to two odors that may be involved in sexual arousal, and that the gay men respond in the same way as women. The new research may open the way to studying human pheromones and provide a biological basis for sexual orientation. Pheromones, which are chemicals given off by one individual to stir some behavior in another of the same species, are known to govern sexual activity in animals. But the role they play, if any, in human sexual attraction is a matter much in dispute. The new research supports the existence of human pheromones. It is being reported today in the Proceedings of the National Academy of Sciences by Dr. Ivanka Savic and colleagues at the Karolinska Institute in Stockholm. The two chemicals in the study were a testosterone derivative produced in men's sweat and an estrogen-like compound found in women's urine. Both have long been suspected of being pheromones. Most odors cause specific smell-related regions of the human brain to light up when visualized by a PET scanner, a form of brain imaging that tracks blood flow and, by inference, illustrates sites where neurons are active. ©2005 San Francisco Chronicle
Keyword: Sexual Behavior; Chemical Senses (Smell & Taste)
Link ID: 7331 - Posted: 06.24.2010
Irvine, Calif., -- A treatment derived from human embryonic stem cells improves mobility in rats with spinal cord injuries, providing the first physical evidence that the therapeutic use of these cells can help restore motor skills lost from acute spinal cord tissue damage. Hans Keirstead and his colleagues in the Reeve-Irvine Research Center at UC Irvine have found that a human embryonic stem cell-derived treatment they developed was successful in restoring the insulation tissue for neurons in rats treated seven days after the initial injury, which led to a recovery of motor skills. But the same treatment did not work on rats that had been injured for 10 months. The findings point to the potential of using stem cell-derived therapies for treatment of spinal cord damage in humans during the very early stages of the injury. The study appears in the May 11 issue of The Journal of Neuroscience. "We're very excited with these results. They underscore the great potential that stem cells have for treating human disease and injury," Keirstead said. "This study suggests one approach to treating people who've just suffered spinal cord injury, although there is still much work to do before we can engage in human clinical tests." Acute spinal cord damage occurs during the first few weeks of the injury. In turn, the chronic period begins after a few months. It is anticipated that the stem cell treatment in humans will occur during spinal stabilization at the acute phase, when rods and ties are placed in the spinal column to restabilize it after injury.
Keyword: Regeneration; Stem Cells
Link ID: 7330 - Posted: 05.11.2005
By Judy Skatssoon, ABC Science Online We're smarter and more creative lying down than standing up, says a researcher who believes this helps to explain Archimedes' eureka moment. Darren Lipnicki from the school of psychology at the Australian National University (ANU) found that people solve anagrams more quickly when they are on their backs than on their feet. He said his research, which will be published in the journal Cognitive Brain Research, relates to how neurotransmitters are released. Lipnicki tested 20 people, who were asked to solve 32 five-letter anagrams, such as 'osien' and 'nodru' while standing and lying down. "I found anagrams were solved more quickly lying down than standing up," he said. "[Often] the solution just pops into the mind similar to the 'aha' or 'eureka' experience associated with large-scale creative breakthroughs. "In that sense anagrams replicate that experience because it's easier to solve them, or solve them more rapidly, lying down. That suggests that creative thinking might also be facilitated when lying down." Lipnicki said his finding relates to the difference in brain chemistry, specifically the release of the neurotransmitter noradrenaline, when lying down or standing up. Copyright © 2005 Discovery Communications Inc.
Keyword: Miscellaneous
Link ID: 7329 - Posted: 06.24.2010
DALLAS - - Barbara Baas ran away from home and tried to kill herself as a teenager. As an adult, she has tried more than 15 varieties of antidepressants. But, thanks to a new weapon, she has finally reached a truce in a 45-year battle. Mrs. Baas says a new treatment for depression is changing her life - so much so that she's willing to drive 115 miles five days a week from Decatur to UT Southwestern Medical Center where she is participating in an experimental study. She undergoes transcranial magnetic stimulation (TMS), a noninvasive, nonpharmacological technology, in which short pulses of magnetic energy stimulate nerve cells in a specific area of the brain - an area that research has shown to be associated with depression. Barbara Baas is undergoing transcranial magnetic stimulation, a new noninvasive treatment for depression that uses magnetic energy to stimulate nerve cells in the brain. Dr. Mustafa Husain, professor of psychiatry at UT Southwestern, is admini-stering the treatment. UT Southwestern is one of 14 sites in the United States, Australia and Canada participating in the clinical trial for TMS. It is being evaluated for treating moderate, chronic and recurring depression, particularly in people who have responded poorly to antidepressant medications. Copyright 2005. The University of Texas Southwestern Medical Center at Dallas
Keyword: Depression
Link ID: 7328 - Posted: 05.11.2005
A study stopped early on safety grounds may still hold the key to a vaccine for Alzheimer's disease, say researchers. An international team tried to boost the body's immune system by injecting patients with the beta amyloid protein that causes the disease. The study was halted in 2002 after a some of the hundreds of patients who took part developed brain inflammation. But two long-term follow up studies, published in Neurology, suggest many patients actually benefited. The results renew hope that it may be possible to develop a vaccine which slows, or even prevents development of Alzheimer's. Now a new vaccine study - which doctors hope will avoid the problems of the 2002 trial - is being launched at 30 centres in the US. Results from the long-term follow up studies show 59 out of 300 patients who received at least one dose of the vaccine produced a significant immune response. This group performed significantly better on a series of memory tests than those who received a dummy injection. Brain scans also showed that their brains shrank in size - possibly because of a removal of built-up beta amyloid deposits. And some of those who responded to the vaccine also showed decreased levels of a protein linked to brain cell death in their spinal fluid. Dr Sid Gilman, of the University of Michigan, was one of those who stopped the original trial. He is also lead author of one of the new papers. He said: "The idea of inducing the immune system to view beta amyloid as a foreign protein, and to attack it, holds great promise. "We now need to see whether we can create an immune response safely and in a way that slows the progression of Alzheimer's disease and preserves cognition." (C)BBC
Keyword: Alzheimers
Link ID: 7327 - Posted: 05.10.2005
By LAWRENCE K. ALTMAN Cocaine users face a newly discovered and possibly fatal risk: coronary aneurysms, a ballooning of the walls of coronary arteries. The condition increases the chance of suffering a heart attack, even years after users stop the drug, researchers in Minnesota are reporting. In an angiogram, the white arrows point to ballooning in the right coronary artery of a 49-year-old man who had used cocaine. The risk of developing an aneurysm was four times as high among cocaine users in their mid-40's as among nonusers in the same age group, according to the study, reported yesterday in the journal Circulation, which is published by the American Heart Association. Aneurysms occurred in 30.4 percent of cocaine users in the study compared with 7.6 percent of non-users. Precisely how much cocaine is needed to produce the aneurysms is not known, but the frequency of use was clearly linked to development of aneurysms, said Dr. Timothy D. Henry, a co-author of the study. "The risk was definitely more common in people who used cocaine at least once a week," said Dr. Henry, who directs research at the Minneapolis Heart Institute Foundation at Abbott Northwestern Hospital. Copyright 2005 The New York Times Company
Keyword: Drug Abuse
Link ID: 7326 - Posted: 05.10.2005
By Samantha Sordyl For most of his career, nationally syndicated cartoonist Scott Adams has needed just two hours to produce a three-panel episode of "Dilbert," his celebrated comic strip satirizing cubicle life and misguided management. Those two hours take him from initial pencil sketch to the final inking of such beloved miscreants as Dogbert, the evil management consultant, who emerges from the pen in "one unbroken smooth line" that extends from his nose to his tail, Adams said. But one morning last November, working in his home office in Dublin, Calif., Adams, 47, found that smooth line nearly impossible to execute. "My pinky started moving again," he said. "Specifically, my pinky flexes. It goes stiff; it goes straight out." That was a cue that his focal dystonia was flaring up to threaten his career once again. Adams was diagnosed with the condition -- a neurological movement disorder, marked by involuntary muscle spasms--back in 1992, around the time he launched "Dilbert." The problem affects his right hand -- the one he uses to draw. "I would look at [my fingers] and tell them to do one thing, and they would do jagged things instead," Adams recalled. "I'd have full muscle control for everything -- except putting a pen to a piece of paper." © Copyright 1996-2005 The Washington Post Company
Keyword: Miscellaneous
Link ID: 7325 - Posted: 06.24.2010
The brain reacts differently to the faces of people from different races, research shows. When volunteers looked at pictures of African-Americans, the brain area that processes emotions became active, a study in Nature Neuroscience found. When they looked at photos of Caucasian faces, the activity was much less. This held true regardless of the race of the observer, which the authors say could mean the patterns reflect learned cultural responses to racial groups. But experts criticised the way the study was carried out and said it was impossible to draw any definite conclusions. Previously, researchers had show that pictures of African-American faces activated the amygdala in Caucasian people. It had been suggested that this might be due to lack of familiarity with other races. But the latest findings, from the University of California, Los Angeles, suggest novelty is not important, since African-American volunteers also had increased activity in the amygdala when they looked at faces of strangers of the same race as themselves. Dr Matthew Lieberman and his team said it was possible that this reflected negative cultural attitudes toward African-Americans. When they asked the 22 volunteers to choose the verbal label for the race of the person in the picture that they were shown, they said they found this dampened down the effect. They said this may have been useful during evolution "to allow controlled processing responses to threat to override automatic responses." (C)BBC
Keyword: Emotions
Link ID: 7324 - Posted: 05.10.2005
Several recent publications have highlighted the neural complexity and intelligence associated with the brains of birds. Many studies suggest that the neural seat of both working memory and executive control - which together encompass planning, creativity, reasoning, abstraction, and most of the other higher-order cognitive properties humans like to claim as their own - lies within the prefrontal cortex. In a new study, Jonas Rose and Michael Colombo investigate the neural basis of executive control in homing pigeons by recording from the nidopallium caudolaterale (NCL), a region of the avian brain considered analogous to the mammalian prefrontal cortex. They show that neurons in the NCL selectively fire when the birds are told to remember and stop firing when they are told to forget. The authors trained five pigeons on a directed forgetting test, a variation on the classic match-to-sample test. After viewing sample stimuli consisting of one of two shapes (a circle or dot) or colors (red or white), the birds were cued to remember or forget the sample (signaled by either a high- or low-frequency tone or one of two distinct patterns). A delay period followed these cues. If a forget cue was presented, the trial ended after the delay, and no memory test was given. If the remember cue was presented, the birds were given a memory test in which they saw two stimuli after the delay; if they responded to the sample stimulus (by pecking on a key), they were rewarded with wheat.
Keyword: Learning & Memory
Link ID: 7323 - Posted: 05.10.2005


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