Tiny particles enter the brain after being inhaled. JIM GILES Nanoparticles - tiny lumps of matter that could one day to be used to build faster computer circuits and improve drug delivery systems - can travel to the brain after being inhaled, according to researchers from the United States1. The finding sounds a cautionary note for advocates of nanotechnology, but may also lead to a fuller understanding of the health effects of the nanosized particles produced by diesel engines. Günter Oberdörster of the University of Rochester in New York and colleagues tracked the progress of carbon particles that were only 35 nanometres in diameter and had been inhaled by rats. In the olfactory bulb - an area of the brain that deals with smell - nanoparticles were detected a day after inhalation, and levels continued to rise until the experiment ended after seven days. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Neurotoxins
Link ID: 4778 - Posted: 06.24.2010

Of Normal Brain Connections Resulting From Sensory Input By Sherry Seethaler Biologists at the University of California, San Diego and the Johns Hopkins University have discovered a gene that plays a key role in initiating changes in the brain in response to sensory experience, a finding that may provide insight into certain types of learning disorders. After birth, learning and experience change the architecture of the brain dramatically. The structure of individual neurons, or nerve cells, changes during learning to accommodate new connections between neurons. Neuroscientists believe these structural changes are initiated when neurons are activated, causing calcium ions to flow into cells and alter the activity of genes. In a paper featured on the cover of the January 9th issue of the journal Science, biologists at UCSD and the Johns Hopkins University medical school report the discovery of the first gene, CREST, known to mediate these changes in the structure of neurons in response to calcium. Copyright ©2001 Regents of the University of California.

Keyword: Development of the Brain
Link ID: 4777 - Posted: 06.24.2010

EUGENE, Ore.-Researchers at the University of Oregon and Stanford University have located a mechanism in the human brain that blocks unwanted memories. This is the first time that anyone has shown a neurobiological basis for memory repression. The findings, by lead researcher Michael Anderson, associate professor of psychology at the University of Oregon, and his colleague, John D.E. Gabrieli, professor of psychology at Stanford, will be published Jan. 9 in Science. The research provides compelling evidence that Freud was on to something 100 years ago when he proposed the existence of a voluntary repression mechanism that pushes unwanted memories out of consciousness. Since then the idea of memory repression has been a vague and highly controversial idea, in part because it has been difficult to imagine how such a process could occur in the brain. Yet, the process may be more commonly applied than was previously thought.

Keyword: Learning & Memory
Link ID: 4776 - Posted: 01.09.2004

EUGENE, Ore.-Researchers at the University of Oregon and Stanford University have located a mechanism in the human brain that blocks unwanted memories. This is the first time that anyone has shown a neurobiological basis for memory repression. The findings, by lead researcher Michael Anderson, associate professor of psychology at the University of Oregon, and his colleague, John D.E. Gabrieli, professor of psychology at Stanford, will be published Jan. 9 in Science. The research provides compelling evidence that Freud was on to something 100 years ago when he proposed the existence of a voluntary repression mechanism that pushes unwanted memories out of consciousness. Since then the idea of memory repression has been a vague and highly controversial idea, in part because it has been difficult to imagine how such a process could occur in the brain. Yet, the process may be more commonly applied than was previously thought.

Keyword: Learning & Memory
Link ID: 4775 - Posted: 01.09.2004

A new Center for Behavioral Neuroscience study has determined that social stress adversely affects digestive function in subordinate cichlid fish. The finding appears in the January issue of the Proceedings of the Royal Society of London. In the study of Central American convict cichlid fish, CBN scientists Ryan L. Earley, Ph.D. and Matthew Grober, Ph.D. of Georgia State University, and Lawrence Blumer, Ph.D. of Morehouse College, compared bile retention and gall bladder size in dominant and subordinate males that had eaten equal amounts of food. The scientists discovered not only were the gall bladders in the subordinate fish much larger, they were filled with dark "bad bile," unlike the pale bile in the dominant fish. The difference in gall bladder function also likely contributed to subordinate fish growing more slowly than the dominant ones. Cichlids have rigid dominance hierarchies, providing excellent models for the study of social stress. Previous cichlid studies have determined that the chronic stress of social subordination has other physiological consequences, including changes in body weight and hormones.

Keyword: Stress; Hormones & Behavior
Link ID: 4774 - Posted: 01.09.2004

The state of Arkansas has executed a man with a severe mental illness. Charles Singleton, 44, was forcibly given anti-psychotic drugs which made him lucid enough under court guidelines to be put to death. A diagnosed schizophrenic, he was given a lethal injection in the state's death chamber in Varner for killing grocery store worker Mary Lou York in 1979. The Governor of Arkansas, Mike Huckabee, had refused to issue a stay of execution. The European Union and Amnesty International had urged the governor to commute the death sentence, saying it was morally reprehensible to execute a person with a severe mental illness. Singleton's lawyer, Jeffrey Rosenzweig, said the execution left him "frustrated, disappointed, saddened". (C) BBC

Keyword: Schizophrenia
Link ID: 4773 - Posted: 01.08.2004

Two deaf women in the US have become the first people to undergo the risky procedure of having implants in their brainstems. The devices are designed to restore hearing by directly stimulating nerves. Some deaf people have been given implants that sit just outside the brainstem, but these do not work very well. Feeding auditory signals directly into the brainstem should work better, but because the brainstem carries signals from the entire body to the brain, any damage caused by an implant could be disastrous. The procedure is far more risky than, say, placing implants in the cortex to try to restore some vision. "If you damage the cortex it's not that big a deal. But at the brainstem level every neuron you damage could damage function," says Bob Shannon of the House Ear Institute in Los Angeles, the surgeon who pioneered the procedure. "We took 15 years to convince ourselves that this could be done safely." © Copyright Reed Business Information Ltd.

Keyword: Hearing
Link ID: 4772 - Posted: 06.24.2010

WEST LAFAYETTE, Ind. – Purdue University researchers have shown that extremely thin carbon fibers called "nanotubes" might be used to create brain probes and implants to study and treat neurological damage and disorders. Probes made of silicon currently are used to study brain function and disease but may one day be used to apply electrical signals that restore damaged areas of the brain. A major drawback to these probes, however, is that they cause the body to produce scar tissue that eventually accumulates and prevents the devices from making good electrical contact with brain cells called neurons, said Thomas Webster, an assistant professor of biomedical engineering. New findings showed that the nanotubes not only caused less scar tissue but also stimulated neurons to grow 60 percent more fingerlike extensions, called neurites, which are needed to regenerate brain activity in damaged regions, Webster said.

Keyword: Glia
Link ID: 4771 - Posted: 06.24.2010

Washington, D.C. -- Georgetown University Medical Center researchers today published the first ever fMRI study of hyperlexia, a rare condition in which children with some degree of autism display extremely precocious reading skills. Appearing in Neuron, the case study uncovers the neural mechanisms that underlie hyperlexia, and suggest that hyperlexia is the true opposite of the reading disability dyslexia. Hyperlexia is found in very rare cases in children who are on the "autism spectrum," meaning they display some characteristics of autism. Like autistic children, children with hyperlexia have extreme difficulty with oral communication, social interaction and expression, and yet can read surprisingly well at a very young age. By some accounts, hyperlexic children can read at 18 months, sometimes two years before they have ever uttered a single word. They are drawn to print, sometimes reading all the signs and license plates they might encounter during a brief walk through the parking lot. The child in this case study, Ethan , reads six to eight years in advance of his age. He read dictionaries in his twos, but spoke his first word at age three and a half.

Keyword: Autism; Language
Link ID: 4770 - Posted: 01.08.2004

Long-lasting depot medication appears safe and effective for treatment of narcotic addiction A study in the January issue of the journal Drug and Alcohol Dependence reports that a long-lasting depot medication appears safe and effective for treatment of narcotic addiction. In the study a single injection prevented withdrawal discomfort for 6 weeks in heroin-dependent patients, reduced the effects of injected opiates, and provided a comfortable detoxification as it gradually wore off. The study medication was an experimental injectable sustained-release depot formulation of the medication buprenorphine. The injection is a suspension of biodegradable microcapsules each containing small amounts of the buprenorphine medication. As the microcapsules gradually disintegrate they provide a long-duration sustained release of buprenorphine. A tablet form of buprenorphine that is taken by holding it under the tongue is already used in the U.S. and around the world as an analgesic and as a treatment for opioid dependence; the tablet normally needs to be taken every day. The recent study was the first to test this new long-lasting depot formulation in humans. The study examined the safety and pharmacokinetics of the depot medication, and tested its effectiveness for reducing the opioid withdrawal syndrome and for reducing the effects of opioid challenge injections.

Keyword: Drug Abuse
Link ID: 4769 - Posted: 01.08.2004

Amyloid beta protein may trigger mental decline. HELEN R. PILCHER Researchers may have pinpointed the cause of Alzheimer's disease - a rogue protein called amyloid beta (Aß) that forms plaques in the brain. Dementia-prone mice with low levels of Aß are spared the disease, research reveals1. Drugs that reduce this protein in humans may have the same protective effect. An estimated 15 million people worldwide suffer from Alzheimer's disease, a progressive, neurodegenerative disease that clouds memory and causes impaired behaviour. Scientists have long known that clumps or plaques of Aß are present in the brains of Alzheimer's patients, but the links between the protein and dementia have been unclear. No one was sure if the plaques were a cause or symptom of the disease. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Alzheimers
Link ID: 4768 - Posted: 06.24.2010

Many people with Alzheimer's disease may be being denied access to drugs which could slow their condition, a study suggests. Statisticians from pharmaceutical firm Pfizer found some parts of the UK spent £10 a head on drugs for the over-65s, but others spent just £1 a head. Campaigners say patients deserve much better, and have called for action from on Health Secretary John Reid. Alzheimer's drugs are supposed to be available across the NHS. The National Institute for Clinical Excellence (NICE) issued guidance in January 2001 which said anti-dementia drugs were clinically and cost effective. The Pfizer team found that overall spending on the drugs had increased sharply since 1991. (C) BBC

Keyword: Alzheimers
Link ID: 4767 - Posted: 01.07.2004

They say that history is written by the winners, but if that's true, then natural history is written by those who can write. Our ancestors split from the ancestors of chimpanzees some 6 or 7 million years ago, and since then they've given rise to perhaps twenty known species of hominids (and potentially many more waiting to be discovered). Today only our own species survives, and only ours has acquired the intelligence to learn things about the distant past--such as the fact that we are the product of evolution. Our survival and our intelligence sometimes blur together, with the result that a lot of the research on human evolution (and most of the popular accounts of it) revolve around what makes our own lineage unique and successful. All the other branches of hominid dynasty become our foil--the losers who, through their extinctions, reveal what is most glorious about ourselves. As a way of thinking, this is both unfair and foolish. We become satisfied with our own false assumptions about other hominids, and may miss some lessons they have for us. Exhibit A: our ancient thick-headed cousin Paranthropus. Paranthropus, which existed from about 2.5 to 1.5 million years ago, was among the first hominids to be discovered by paleoanthropologists. In 1938, a young South African schoolboy led Robert Broom to a spot where he had found fossils of jaws and teeth. Broom dug up more pieces of the skull and realized that it belonged to some kind of ape. A closer look revealed that it was more like humans than chimps or gorillas. For example, the hole at the base of the skull was far forward like humans, suggesting that the creature could walk upright. But compared to the other hominids that had been found at that point, Paranthropus was peculiar for its big frame and its massive jaws and teeth. If paleoanthropologists had to pick a hominid that looked like our direct ancestor, Paranthropus was definitely not it.

Keyword: Evolution
Link ID: 4766 - Posted: 01.07.2004

NewScientist.com news service American footballers sustain a blow to the head equivalent to a severe car crash in every game, a new study has found. Furthermore, players sustain an average of 50 knocks to the head, each equal to a boxer's punch, in every match, according to the first results from researchers at Virginia Tech, North Carolina, US. Stefan Duma and colleagues used helmet sensors on their college football team to measure the movement of the head due to blows. The average force of a blow was 40G - 40 times the force of gravity. "That's loosely analogous to a boxer punching another boxer with a gloved hand," says Duma, director of the Center for Injury Biomechanics. © Copyright Reed Business Information Ltd.

Keyword: Brain Injury/Concussion
Link ID: 4765 - Posted: 06.24.2010

A research biologist at Wright State University is studying rhythmic cycles in birds to learn if we have a physiological clock in our stomach that determines when we get hungry. Thomas Van’t Hof, Ph.D., an assistant professor of biological sciences, recently returned from Japan, where he presented lectures and conducted research on circadian (24-hour) rhythms in birds. He visited Okayama University of Science, a sister university of Wright State, plus the University of Tokyo and Nagoya University. “We often think of our stomachs as having a clock,” he said. “We anticipate food, and our gastrointestinal tract is prepared for food when it arrives. Our research investigates how this happens.”

Keyword: Obesity; Biological Rhythms
Link ID: 4764 - Posted: 06.24.2010

Scientists believe the may have found a way to protect people against every strain of meningitis. Researchers at the University of Surrey have developed a vaccine which protects mice against the deadly disease. While much more research is needed, they believe it could be an important first step towards creating a single vaccine to protect humans. A vaccine against the A and C strains of the disease exists. However, there is no jab against the lethal B strain. It infects around 3,000 Britons a year and kills hundreds. One in 10 children who contract the disease die from it. Many others are left severely handicapped. The scientists used genetic engineering technology to create a strain of meningitis B that is incapable of causing disease. (C) BBC

Keyword: Miscellaneous
Link ID: 4763 - Posted: 01.06.2004

Blame biology, not parenting, new theory suggests By Ellen Ruppel Shell, Globe Correspondent, Anorexia, she contends, is not primarily a psychological condition brought on by a troubled childhood -- as is often thought -- but a disorder based in biology, specifically in the appetite regulation mechanism in the brain. Her theory postulates that anorexics have a biological adaptation to weight loss that causes their bodies to shut off hunger signals, and to ratchet up physical activity, even as their flesh melts away. "Anorexics are often told to stop dieting, to listen to their body and to give it what it wants," Guisinger said. "But the reality is that they are listening to their bodies, and their bodies are telling them not to eat. The truth is, they have to stop listening." Guisinger, who has treated eating disorders in private practice in Missoula, Mont., for nearly two decades, trained in evolutionary biology in the late 1970's before getting a doctorate in clinical psychology at the University of California at Berkeley. This background, coupled with her upbringing on a farm in Washington state, convinced her that Freudian and other purely psychological explanations for anorexia were inadequate. © Copyright 2003 Globe Newspaper Company.

Keyword: Anorexia & Bulimia
Link ID: 4762 - Posted: 06.24.2010

Scientists may have found what they hope is a less controversial way of getting special human cells that can turn into any part of the body and potentially solve many diseases. Scientists already know they can get these cells from human embryos—but many people oppose this and the federal government has banned most research. But as this ScienCentral News video reports, this new source doesn't use embryos. Stem cell research is leading scientists to investigate the possibility of regenerative or reparative medicine—treatments in which stem cells "turn into" a specific cell type required to repair damaged adult cells. It's a controversial topic because one source of stem cells is the destruction of embryos. But genetics researchers say they found a new source for stem cells—unfertilized egg cells created by a process called parthenogenesis, a form of reproduction in which the egg develops without being fertilized. © ScienCentral, 2000-2003.

Keyword: Stem Cells
Link ID: 4761 - Posted: 06.24.2010

Modern armor results in fewer deaths -- more amputees Carl T. Hall, Chronicle Science Writer Some of the more lingering effects of the war in Iraq may soon be felt in the San Francisco workshop of Charles McIntyre. He fashions prosthetic limbs for amputees -- increasingly sophisticated devices engineered of metal, high-tech carbon-fiber composites and molded plastics. Wars and their grisly aftermath have always been an important driver of medical research and clinical innovations, and the continuing insurgency in Iraq is proving no different. Already, the conflict has produced some 2,700 U. S. war wounded, including a growing roster of American soldiers returning home with missing limbs and eyes damaged by shrapnel. ©2004 San Francisco Chronicle

Keyword: Robotics; Vision
Link ID: 4760 - Posted: 06.24.2010

By MARY DUENWALD Now that ephedra is to be banned, the millions of people who have been taking the supplement to lose weight or control it may find themselves looking for an alternative. But weight-loss and nutrition experts nationwide say that no other over-the-counter supplements advertised as weight-loss aids are as effective as ephedra. "I'm not pushing ephedra, and I wouldn't recommend it to anybody, but several very good studies have shown that ephedra combined with caffeine promotes weight loss," said Dr. Ken Fujioka, director of the Nutrition and Metabolic Research Center at the Scripps Clinic in San Diego. "I don't know of any other over-the-counter preparation that has shown that kind of consistent effect." Claims that other supplements — from bitter orange to green tea extract to herbal laxatives — can promote weight loss are not backed up by long-term studies in humans. Copyright 2004 The New York Times Company

Keyword: Obesity
Link ID: 4759 - Posted: 06.24.2010