When Angelique Tung escaped from the South Tower on September 11th, 2001 she didn't know she was pregnant. Originally from California, she was visiting New York for a business meeting on the 78th floor. Like so many, the images of that day are ingrained in her mind. She remembers her sales manager saying, "You've got to get out of the building." She remembers looking through the giant South Tower windows at smoke, paper, and debris billowing out of the North Tower. And she remembers the impact of the second plane. "Quite frankly I was surprised I was pregnant because I thought this trauma would have caused a miscarriage," Tung says. During her pregnancy she was nervous anytime planes flew too close to her Los Angeles office building. Tung says she also felt anxious and never wanted to travel far from home. Concerned for how her mental state might affect her unborn child, she began to see a psychologist who told her she had symptoms of post-traumatic stress disorder, or PTSD. She is now the mother of two. She says her older son seems like a normal little boy, but notes that he "has fears" and is "definitely more risk-averse" than his younger brother. Though she's no doctor, and can't tell if her son's behavior is just what she would call "first child syndrome" or actually associated with her own trauma, her observation is not unfounded. © ScienCentral, 2000-2005

Keyword: Stress; Development of the Brain
Link ID: 7870 - Posted: 06.24.2010

By Larry O'Hanlon, Discovery News —Hurricane Katrina's rampage didn't stop some deep-sea biologists in her path from making new discoveries before they had to run for their lives. Scientists aboard the Harbor Branch Oceanographic Institution's Seward Johnson announced that they caught a second glimpse of a mysterious new kind of giant squid and reeled up a deep sea crab that can see ultraviolet light. The secret to their success was the innovative Eye-in-the-Sea apparatus, which uses dim red light to watch animals attracted to a pile of bait. This year's big discovery of the ultraviolet-seeing crab raises the question of what the crab sees in UV at 1,700 feet under Gulf of Mexico waves, where no solar UV can reach. "It was totally unexpected," said chief scientist Tammy Frank of the UV-seeing crab. To discover the crab's secret, it had to be carefully brought up from the depths in a cold, dark container. The depressurization was not so much an issue because crabs have no swim bladders, and so are not sensitive to pressure changes as are many fish. Copyright © 2005 Discovery Communications Inc

Keyword: Vision; Evolution
Link ID: 7869 - Posted: 06.24.2010

Roxanne Khamsi When it comes to deadly protein clusters in the brain, size matters. The human equivalent of mad cow disease, variant Creutzfeldt-Jakob disease (vCJD) is thought to be caused by misshapen proteins, known as prions, that infect the brain. Research now shows that the most infectious strings of prions are of a middling length; clumps that are longer or shorter are less problematic. The findings, reported in this week's Nature1, could convince medical experts to rethink how they plan to treat illnesses such as vCJD, as well as Alzheimer's and Parkinson's. Researchers have often debated whether longer or shorter chains of prions are more problematic. The molecules seem to multiply by converting the normal proteins that they touch to an irregular form. Long ones form visible tangles in the brain, but short ones might be more capable of spreading the infection. Jay Silveira and his colleagues at the Rocky Mountain Laboratories in Hamilton, Montana, obtained misshapen prion proteins from hamsters, broke them up using a detergent, and sorted them according to size. They then injected strings of known length into other hamsters. ©2005 Nature Publishing Group |

Keyword: Prions
Link ID: 7868 - Posted: 06.24.2010

UPTON, NY - A new set of experiments in mice confirms that a brain receptor associated with the reinforcing effects of marijuana also helps to stimulate the rewarding and pleasurable effects of alcohol. The research, which was conducted at the U.S. Department of Energy’s Brookhaven National Laboratory and was published online September 2, 2005 by the journal Behavioural Brain Research, confirms a genetic basis for susceptibility to alcohol abuse and also suggests that drugs designed to block these receptors could be useful in treatment. “These findings build on our understanding of how various receptors in the brain’s reward circuits contribute to alcohol abuse, help us understand the role of genetic susceptibility, and move us farther along the path toward successful treatments,” said Brookhaven’s Panayotis (Peter) Thanos, lead author of this study and many others on “reward” receptors and drinking (see: this release and , www.bnl.gov/thanoslab). Earlier studies in animals and humans have suggested that so-called cannabinoid receptors known as CB1 — which are directly involved in triggering the reinforcing properties of marijuana — might also stimulate reward pathways in response to drinking alcohol. Thanos’ group investigated this association in two experiments.

Keyword: Drug Abuse
Link ID: 7867 - Posted: 06.24.2010

Smokers are twice as likely as non-smokers to lose their sight in later life, experts warn. The link between age-related macular degeneration (AMD) and smoking is now as robust as that between smoking and lung cancer, they say. Yet many smokers are still unaware that their habit could cost them their sight. AMD Alliance UK and the Royal National Institute of the Blind are calling for specific warnings on cigarette packets. They would also like the government to fund an awareness campaign to alert people to the dangers of smoking, as well as the introduction of a complete ban on smoking in all enclosed public places across the UK. AMD usually develops after a person reaches 50 years and affects the central part of the retina of the eye. It is the UK's leading cause of sight loss - there are around 500,000 people in the UK with AMD. An estimated 54,000 people have the condition as a result of smoking. Yet a report by AMD Alliance UK reveals that only 7% of people know that AMD affects the eyes, based on a survey of 1,023 UK adults. However, seven out of 10 smokers would either stop smoking permanently (41%) or cut down (28%) if they thought it could harm their eyesight. (C)BBC

Keyword: Drug Abuse
Link ID: 7866 - Posted: 09.07.2005

A quick word test may allow simpler, earlier diagnosis of Alzheimer's disease, according to a new study. UK researchers have found that patients in the early stages of the disease consistently forgot words they learned later and used less in life. Word tests which identify this pattern of vocabulary loss may therefore provide a new way to screen patients. Early diagnosis of Alzheimer's is important to maximise the benefit of currently available treatments. The study, conducted by Andy Ellis of the University of York and his collaborators at the Universities of Hull and Aberdeen, characterised shrinking vocabulary in the early stages of the disease. The researchers asked 96 Alzheimer's patients and 40 healthy people of similar age to list all the animals they could in one minute. In a second minute, the test subjects were asked to list types of fruit. While the healthy subjects were able to list 20-25 words, on average, those suffering from Alzheimer's could list only 10-15, indicating a constriction of their active vocabulary. The lost words tended to be those learned later in childhood and encountered less frequently in everyday life. (C)BBC

Keyword: Alzheimers
Link ID: 7865 - Posted: 09.07.2005

In findings that support a relationship between agricultural chemicals and Parkinson's disease, two groups of researchers have found new evidence that loss of DJ-1, a gene known to be linked to inherited Parkinson's disease, leads to striking sensitivity to the herbicide paraquat and the insecticide rotenone. The two studies were performed with the fruit fly Drosophila, a widely used model organism for studies of human disease, and shed new light on biological connections between inherited and sporadic forms of Parkinson's disease. The work is reported in Current Biology by two independent groups, one led by Nancy Bonini of the University of Pennsylvania and the Howard Hughes Medical Institute, and the other led by Kyung-Tai Min of the NINDS branch of the U.S. National Institutes of Health. Parkinson's disease occurs both sporadically and as a result of inheritance of single gene mutations. One of the most common neurodegenerative disorders, it is associated with the progressive and selective loss of a specific population of neurons in the brain, the dopaminergic neurons of the substantia nigra pars compacta . Exposure to several common environmental toxins, thought to injure neurons through oxidative damage, has been shown to be associated with sporadic forms of Parkinson's disease. During the past decade, researchers have also made remarkable progress in identifying genes responsible for inherited forms of Parkinson's disease, with the expectation that understanding the function of these genes will elucidate mechanisms behind sporadic Parkinson's disease. Past work had shown that one form of familial Parkinson's disease results from a loss of function of a gene called DJ-1.

Keyword: Parkinsons; Neurotoxins
Link ID: 7864 - Posted: 09.07.2005

Evolution of Brain, Cognition, and General Intelligence by David C. Geary Review by Keith Harris, Ph.D. Why and how have humans developed a type of consciousness unlike that of other creatures? Although targeted at readers already knowledgeable in this area, this book does a very good job of developing and extending evolutionary theory to explain our cognitive faculties. The author's background in developmental psychology (in which he holds a doctorate) serves as a solid platform for this overview of the history of the human brain, including the evolution of our type of intelligence and the intricate social functioning for which it serves so well. Having previously published over a hundred professional articles and several books, in this work, Geary gets at what are among the most interesting -- and largely unresolved -- issues about being human: why are we conscious and why do we have such a well-developed sense of self? The first chapter is a concise integration of the facts, themes and arguments that make up the book. The second chapter covers the basic processes that underlie the evolution of species, and does so in a thorough but concise manner. Readers are advised to pay close attention to the first two of the books' nine chapters, as a good grasp of these are needed well for an understanding the later chapters. © CenterSite, LLC, 1995-2005

Keyword: Evolution
Link ID: 7863 - Posted: 06.24.2010

New York - Doctors commonly view excessive daytime sleepiness as a cardinal sign of disturbed or inadequate sleep. But a new study suggests it could also signal depression or even diabetes, regardless of whether an individual doesn't sleep well. Among a random sample of 16,500 men and women ranging in age from 20 to 100 years old from central Pennsylvania, 8.7 percent had excessive daytime sleepiness. Researchers, who considered a wide range of possible reasons for why these individuals were excessively sleepy during the daytime, found that excessive daytime sleepiness was more strongly associated with depression and obesity or metabolic factors than with sleep-disordered breathing or sleep disruption. Depression was by far the most significant risk factor for excessive daytime sleepiness, they report in the Journal of Clinical Endocrinology and Metabolism. The likelihood of being excessively sleepy during the daytime was more than three times higher in those who reported they were being treated for depression. The investigators also observed strong ties between excessive daytime sleepiness and diabetes. Individuals reporting treatment for diabetes were close to two times more likely to report excessive daytime sleepiness than those who were not being treated for diabetes. © 2005 Independent Online.

Keyword: Sleep; Depression
Link ID: 7862 - Posted: 06.24.2010

Working long hours is considered a hallmark of a medical residency. But in recent years, concerns have risen about how shifts that can last days affect a doctor's ability to function. The results of a new study quantify the negative effects and show that the performance of fatigued residents is comparable to how they would act after imbibing three or four cocktails. An 80-hour limit for a resident's workweek was introduced in July 2003 in response to concerns about overwork. In the new study, J. Todd Arnedt of the University of Michigan and his colleagues measured the performance of 34 doctors on an attention test and in a driving simulator after being on call. The volunteers took part in the tests on four different occasions, both after working mostly day shifts with only a few overnight calls, and after working intense overnight shifts that added up to about 80 hours in a week. For some of the tests, the doctors were also given alcoholic drinks or nonalcoholic placebos. After a month of difficult work schedules, the doctors exhibited reaction times that were seven percent slower than their responses after working a lighter schedule. In the driving simulator, doctors coming off a month of working nights displayed comparable skills to the subjects who had an easier schedule but had a blood-alcohol level just below the legal driving limit. What is more, the post-call doctors were 30 percent more likely to not maintain a steady speed in the driving simulator compared to well-rested doctors who had been drinking. © 1996-2005 Scientific American, Inc

Keyword: Sleep
Link ID: 7861 - Posted: 06.24.2010

As college campuses start filling up with students, you can expect students to start filling up with beer. With more than 40 percent of U.S. college students binge drinking, this nationwide problem resurfaces yearly when students get ready to hit the books. Looking for a possible remedy, Harvard Medical School psychopharmacologist Scott Lukas turned to a binger of the plant world — kudzu — an invasive species that grows so aggressively that "it's been called 'the vine that ate the South,'" Lukas says. The legume kudzu (Pueraria montana), a native plant of Asia, was introduced to the U.S. in the 1800's. It is favored for its large leaves and sweetly fragrant blossoms, and was also used as a method for controlling soil erosion and animal forage. But like many non-native species it began to get out of control — engulfing farms and buildings — and became despised in southeastern states for its aggressive growth. Kudzu was eventually declared a weed by the U.S. Department of Agriculture. "Unfortunately it doesn't really have any natural enemies in this country, so it grows rather vigorously throughout the South," says Lukas. Ancient Chinese lore has suggested that kudzu might be used in treating a variety of alcohol related problems. And previous studies showed that this pesky vine — which contains a total of seven isoflavones, or plant hormones — curbed alcohol intake in animals. So Lukas tried it in a small pilot study on heavy drinking college students. "These are individuals who would drink multiple times during the week and oftentimes would drink four and five drinks at one sitting," he says. © ScienCentral, 2000-2005.

Keyword: Drug Abuse
Link ID: 7860 - Posted: 06.24.2010

Durham, N.C. -– Duke University Medical Center researchers have found that the naturally occurring marine toxin domoic acid can cause subtle but lasting cognitive damage in rats exposed to the chemical before birth. Humans can become poisoned by the potentially lethal, algal toxin after eating contaminated shellfish. The researchers saw behavioral effects of the toxin in animals after prenatal exposure to domoic acid levels below those generally deemed safe for adults, said Edward Levin, Ph.D. Those effects –- including an increased susceptibility to disruptions of memory -- persisted into adulthood, he said. The findings in rats, therefore, imply that the toxin might negatively affect unborn children at levels that do not cause symptoms in expectant mothers, said Levin. While the researchers note that eating seafood offers significant health benefits, they said their findings suggest that the current threshold of toxin at which affected fisheries are closed should perhaps be lowered. The Federal Drug Administration (FDA) set the current limit based on levels safe for adults, Levin said. "A single administration of domoic acid to pregnant rats had a lasting affect on the performance of their offspring as adults," Levin said. "The consequences are life-long. "The findings suggest we may need to re-evaluate monitoring of waters, shellfish and fish to make sure that the most sensitive parts of the human population are protected from toxic exposure to domoic acid," he continued. © 2001-2005 Duke University Medical Center

Keyword: Neurotoxins; Development of the Brain
Link ID: 7859 - Posted: 06.24.2010

Four sugar-coated faces made by stem cells as they differentiate into brain cells during development have been identified by scientists. These unique expressions of sugar on the cell surface may one day enable stem cell therapy to repair brain injury or disease by helping stem cells navigate the relative “jungle” of the adult brain, says Dr. Robert K. Yu, director of the Institute of Neuroscience and the Institute for Molecular Medicine and Genetics at the Medical College of Georgia. “These glycoconjugate markers are like specific addresses that characterize the cell at that particular moment. We call them stage-specific embryonic antigens,” says Dr. Yu of recognition molecules that assist in the unbelievably rapid assemblage of 100 billion to 200 billion cells into a brain in nine months. The four compounds – two glycolipids, GD3 and O-acetylated GD3, and two glycoproteins, Stage-specific Embryonic Antigen-1 and Human Natural Killer Cell Antigen 1 – were known, but their role in helping cells migrate where and when needed was unknown. Copyright 2005 Medical College of Georgia

Keyword: Stem Cells
Link ID: 7858 - Posted: 06.24.2010

By experimentally relocating migratory white-crowned sparrows (Zonotrichia leucophrys gambelii) from their breeding area in the Canadian Northwest Territories to regions at and around the magnetic North Pole, researchers have gained new insight into how birds navigate in the high Arctic. In particular, the findings aid our understanding of how birds might determine longitudinal information--a challenging task, especially at the earth's poles. The work is reported in Current Biology by Susanne Åkesson and colleagues at Lund University in Sweden. Migratory birds navigating over long distances can determine their latitude on the basis of geomagnetic and celestial information, but longitudinal position is much more difficult to determine. In the new work, researchers investigated whether birds can define their longitude after physical displacements in the high Arctic, where the geomagnetic field lines are steep and the midnight sun makes star navigation impossible for much of the summer. White-crowned sparrows are nocturnally migrating birds that breed in northern Canada and perform long migrations covering a few thousand kilometers to winter in the southern United States. In the study, young and adult white-crowned sparrows were captured with mistnets near Inuvik, NW Territories, Canada, during mid-July to mid-August--the end of the breeding period and shortly before migration--and transported by a Canadian icebreaker along a northeasterly route to nine sites on the tundra, among them the magnetic North Pole (located on Ellef Ringnes Island). The researchers then recorded the birds' directional orientation in cage experiments.

Keyword: Animal Migration
Link ID: 7857 - Posted: 09.07.2005

By ANAHAD O'CONNOR THE CLAIM Need a reason to tear yourself from that sleek new MP3 player you can't put down? While most people covet the hours of nonstop music and the snug earpieces, those features, and others, are also the reasons the players may hurt your hearing. Really? The component that can have the greatest impact is the headphone. In a study published last year in the journal Ear and Hearing, Dr. Brian Fligor of Harvard Medical School looked at a variety of headphones and found that, on average, the smaller they were the higher their output levels at any given volume control setting. Compared with larger headphones that cover the entire ear, some insertable headphones, like the white ones sold with iPods, increased sound levels by up to nine decibels. That may not seem like much, but because decibels are measured in logarithmic units, it can mean the difference between the noise output of an alarm clock (about 80 decibels) and that of a lawnmower (about 90 decibels). The other problem, a second study found, is that insertable headphones are not as efficient at blocking background noise as some larger ones that cover the ear, so there is more incentive to turn up the volume. Copyright 2005 The New York Times Company

Keyword: Hearing
Link ID: 7856 - Posted: 09.07.2005

By RICHARD SALTUS On the Fourth of July, a 63-year-old man was taken by wheelchair into the emergency room of a suburban Virginia hospital, overwhelmed with dizziness and nausea and gripped by sweat-inducing anxiety. John Farquhar suffered a severe bout of dizziness after lifting his dog high in the air. "I felt dim and lightheaded, like I was just going to fade out," said John Farquhar, a semiretired consultant in Washington. "I said, 'I'm going to die.' " His wife, Lou, a nurse, had driven him to the hospital, taking big curves gingerly because the motion of a sweeping turn "made me feel like I was pulling 30 G's like a fighter pilot," said Mr. Farquhar, who otherwise was healthy and fit. The attacks had begun the previous day, out of the blue, while he was playing with the couple's dog, Sascha. Lifting her high in the air, "I snapped my head back, and suddenly it seemed that my body was turning, and the room was spinning around," Mr. Farquhar recounted. "I felt profoundly dizzy and nauseated." The episode passed, but the queasiness returned not long afterward, set off by the on-screen action on a DVD. When Mr. Farquhar got out of bed the next day, the world was spinning so violently that he crumpled to his knees, and he could barely make his way to the bathroom, where he vomited, leading to the trip to the E.R. Copyright 2005 The New York Times Company

Keyword: Stroke
Link ID: 7855 - Posted: 09.06.2005

Notebook by Mick Hume NONE OF MY best friends are chimpanzees or gorillas. I have never had a problem seeing “our closest cousins” as suitable subjects for scientific research that could improve the human lot. Better to be thought a “speciesist” than be a specious sentimentalist. Now scientists have mapped the genetic blueprint of the chimpanzee, establishing that we share almost 99 per cent of functional genes and 96 per cent of our wider DNA. Arguments about our genetic closeness were used to ban experiments on great apes in the UK in 1986. But look at things from the perspective of human liberation for a change, and we could draw the opposite conclusion. Surely it is our genetic similarity to these great apes that could make it medically useful to experiment on them. And it is the yawning difference between us and them that should make it morally acceptable. “The philosophical goal is that we all want to know what makes us human,” says one of the international research team that sequenced the chimp genome. “The pragmatic goal is that it will help us understand diseases and conditions that are unique to humans.” No doubt genetic research will bring many benefits. However, studying the genetic make-up of great apes, or indeed of Homo sapiens, will never tell the full story of “what makes us human”. Copyright 2005 Times Newspapers Ltd.

Keyword: Animal Rights
Link ID: 7854 - Posted: 06.24.2010

By NICHOLAS BAKALAR Using brain scanning techniques, researchers have located a specific part of the brain that causes people with asthma to wheeze and gasp for breath when under emotional stress. Their report, released on Aug. 29, will appear in the Sept. 13 issue of The Proceedings of the National Academy of Sciences. Asthma sufferers often note that anxiety and emotional turmoil make the symptoms of an attack much worse, and in some cases, emotion alone can precipitate an attack. Previous research has shown, for example, that college students with asthma have greater airway inflammation when they are exposed to an allergen during exam week than when the exposure occurs at a less stressful time. Though these psychological exacerbations of asthma were well known, the physical connection between the brain and the immune system had not been described. Richard J. Davidson, the senior author of the paper and a professor of psychology and psychiatry at the University of Wisconsin, said the work showed that when people with asthma are exposed to their allergen, "you find certain centers in the brain that we know are intimately involved in emotions that get activated." Copyright 2005 The New York Times Company

Keyword: Neuroimmunology; Stress
Link ID: 7853 - Posted: 09.06.2005

By NICHOLAS WADE Only in science fiction do people's minds get possessed by alien beings. For grasshoppers, zombification is an everyday hazard, and it obliges them to end their lives in a bizarre manner. Biologists have discovered and hope to decipher a deadly cross talk between the genomes of a grasshopper and a parasitic worm that infects it. The interaction occurs as the worm induces the grasshopper to seek out a large body of water and then leap into it. The parasite, known as a hairworm, lives and breeds in fresh water. But it spends the early part of its life cycle eating away the innards of the grasshoppers and crickets it infects. When it is fully grown, it faces a difficult problem, that of returning to water. So it has evolved a clever way of influencing its host to deliver just one further service - the stricken grasshopper looks for water and dives in. The suicidal behavior of the infected grasshoppers has been studied by a team of biologists from the French National Center for Scientific Research in Montpellier, France, led by Frédéric Thomas and David Biron. They did their fieldwork around a swimming pool on the border of a forest near Avène les Bains in southern France. Hordes of infected grasshoppers - more than 100 a night - arrive at the pool during summer nights at the behest of the parasites. Copyright 2005 The New York Times Company

Keyword: Miscellaneous
Link ID: 7852 - Posted: 09.06.2005

WHITE PLAINS, N.Y., – Folic acid fortification of grain foods has produced a one-third decline in serious birth defects of the brain and spine, but the March of Dimes urged federal officials to help spare a greater number of babies from these devastating conditions by requiring higher levels of the B vitamin. The March of Dimes restated its longtime position in response to two articles published today in Pediatrics. "It's so rare that we get the opportunity to save thousands of babies from being born with a disabling or fatal birth defect with such a simple, low-tech means as folic acid fortification," says Dr. Jennifer L. Howse, president of the March of Dimes. "Studies have shown that adequate daily folic acid intake beginning before pregnancy can reduce the incidence of these tragic birth defects by up to 70 percent, and we should not settle for anything less than maximum prevention." Since 1996, the March of Dimes has recommended that the U.S. Food and Drug Administration set the level of folic acid required in enriched grain foods at 350 micrograms per 100 grams of grain to prevent as many neural tube defects (NTDs) as possible, said Dr. Howse.

Keyword: Development of the Brain
Link ID: 7851 - Posted: 06.24.2010