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December 15, 2006, 4:39 AM CT

Software Automates Access to Brain Atlases

Software Automates Access to Brain Atlases
USC computer researchers have found a cheap, quick and copyright- respecting way to turn existing print brain atlases into multimedia resources. The software, now available in an experimental beta version for free download, is a robust and user-friendly interface that works on all the most popular computer operating systems.

"Brain atlases are basic tools for scientists in neural science," says Gully A.P.C. Burns, a specialist in neuroinformatics who works as a research scientist at the University of Southern California's Information Sciences Institute, part of the USC Viterbi School of Engineering. "Our NeuARt II system will make them much more user-friendly.

The same viewing system, Burns believes, can help neuroresearchers store, organize and use data from ongoing experiments.

Burns was part of a team of computer experts and neuroresearchers that worked with Larry W. Swanson of the USC Neuroscience Institute, author of the standard printed rat brain atlas, Brain Maps, Structure of the Rat Brain, (Elsevier Academic Press, 1992-2004) to produce the NeuroARt II viewer, following up on years of earlier development. "The entire design of our approach arose from practical methods" from Swanson's lab, as per a paper on the project Burns co-authored, published this month in the online journal BMC Bioinformatics.........

Posted by: Daniel      Permalink         Source


December 12, 2006, 4:49 AM CT

'ZIP Code' Spurs Cargo Transport in Neurons

'ZIP Code' Spurs Cargo Transport in Neurons Highly prized in the kitchen and the lab Squid have a giant axon that is 1,000 times wider than the average human.
Image: Russell Jacobs, Elaine Bearer/MBL
For the first time, scientists have identified a peptide that can spur cargo transport in nerve cells, a discovery that could help researchers better understand nerve cell function and test possible therapies for neurodegenerative diseases.

Elaine Bearer, a professor at Brown Medical School, led the research, which was conducted at the MBL (Marine Biological Laboratory) in Woods Hole, Mass., where Bearer was a Dart Scholar and is a Whitman investigator. Reported in the Proceedings of the National Academy of Sciences online early edition, the research shows that a peptide, or protein bit, can hitch biological material onto molecular motor machinery, acting as a "ZIP Code" that directs the shipment to the synapse.

The peptide comes from amyloid precursor protein, or APP, a principal component of plaques found in the brains of people with Alzheimer's disease. Researchers have long known that APP can break down and form these plaques and that mutations in this protein lead to early onset of Alzheimer's disease. Until now, however, little was understood about the function of APP in healthy nerve cells.

The research also sheds light on the complex intracellular transport system inside nerve cells. This transport system is critical to nervous system function, bringing proteins and RNA from the cell body down a neuron's spindly axon to the synapse, the major site of information exchange and storage in the nervous system. Without this precious cargo, neurons can't communicate. Memories can't be made. Learning can't take place. And neurons die.........

Posted by: Daniel      Permalink         Source


December 11, 2006, 4:57 AM CT

Challenging The Theory Of Memory Storage

Challenging The Theory Of Memory Storage The brain’s neocortex (blue) and the hippocampus (red)
Image: Mayank Mehta/Brown Universit
Daily events are minted into memories in the hippocampus, one of the oldest parts of the brain. For long-term storage, researchers think that memories move to the neocortex, or "new bark," the gray matter covering the hippocampus. This transfer process occurs during sleep, particularly during deep, dreamless sleep.

A number of neuroresearchers have embraced and built upon this theory of memory storage, or consolidation, for a generation. But the theory is difficult to test. New research led by Brown University neuroscientist Mayank Mehta, conducted with Nobel Prize-winning physiologist Bert Sakmann, shows the best evidence yet of the sleep dialogue between the old brain and the.

Their work, published in Nature Neuroscience, also shows that this interaction occurs in a startling way. Instead of the hippocampus uploading information to the neocortex in a burst of brain cell communication, Mehta found the opposite: the neocortex seems to drive the dialogue with the hippocampus.

The findings may give researchers a new understanding of how the brain manages memories in health and during dementia, offering up a fresh look at the causes of diseases such as Alzheimer's, as well as potential therapys.

"Long-term memory making may be a very different process than we previously thought," said Mehta, an assistant professor in the Department of Neuroscience at Brown. "Either this reversed dialogue is, somehow, a part of memory storage or this transfer of information from the old to the new brain may not occur during sleep. Either way, the results call into question usually held theories about the role of cortico-hippocampal dialogue in sleep".........

Posted by: Daniel      Permalink         Source


December 5, 2006, 9:25 PM CT

Virtual Reality Can Improve Memory

Virtual Reality Can Improve Memory
Conventional wisdom tells us that experience is the best teacher. But a new study of virtual marketing strategies finds that this isn't always true. Ann E. Schlosser (University of Washington) tested how well people used a camera after learning about its functions two different ways: either through an interactive virtual rendition or through text and static pictures. She observed that though virtual experiences improved people's memories of the camera's functions, it also increased false positives that is, more people believed it could do things that it couldn't do.

"Eventhough object interactivity may improve memory of associations in comparison to static pictures and text, it may lead to the creation of vivid internally-generated recollections that pose as memories," Schlosser writes in the recent issue of the Journal of Consumer Research.

In addition, though the virtual experience was better for retaining information, it didn't help test subjects recognize the actual items when presented in real life: "The benefits of learning via virtual experience may come with costs: the ease of generating mental images may create later confusion regarding whether a retrieved mental image waccording toceived or imagined," she writes.

Schlosser also warns that while it might seem advantageous if consumers think a product has features it doesn't actually have, this can actually lead to customer dissatisfaction. She explains, "Consumers who discover that the product does not have these attributes will likely feel misled by the company".........

Posted by: Daniel      Permalink         Source


November 20, 2006, 5:08 AM CT

Yeast Model Shows Promise As Alzheimer's Test

Yeast Model Shows Promise As Alzheimer's Test
A century ago this month, German psychiatry expert Alois Alzheimer formally described characteristics of the neurodegenerative disease which ultimately came to bear his name. While international efforts to learn about Alzheimer's disease and develop therapys have progressed significantly in recent years, a cure remains an elusive goal.

A new research tool developed by Susan Liebman, distinguished university professor of biological sciences at the University of Illinois at Chicago, may ultimately provide a means for treating the earliest stage of Alzheimer's, thereby stemming its progression.

Typically alzheimer's disease is characterized by the formation of plaques in the brain largely composed of fibers made from a peptide called beta-amyloid, or A-beta, for short. There is abundant evidence to support the hypothesis that accumulation of A-beta peptide triggers the appearance of Alzheimer's. But while earlier research suggested the A-beta fiber caused Alzheimer's, recent research points at much smaller aggregates of the peptide as the culprit.

"We've developed a yeast model system in which A-beta small aggregate formation can be detected," said Liebman. "The system employs a fusion of the human A-beta peptide to a functional yeast protein, called a reporter protein, which is only active in allowing cells to grow on test media if the fusion does not form aggregates".........

Posted by: Daniel      Permalink         Source


November 15, 2006, 4:43 AM CT

Nanoparticles To Target Brain Cancer

Nanoparticles To Target Brain Cancer
Tiny particles one-billionth of a meter in size can be loaded with high concentrations of drugs designed to kill brain cancer. What's more, these nanoparticles can be used to image and track tumors as well as destroy them, as per scientists at the University of Michigan Comprehensive Cancer Center.

Scientists incorporated a drug called Photofrin along with iron oxide into nanoparticles that would target malignant brain tumors. Photofrin is a type of photodynamic treatment, in which the drug is drawn through the blood stream to tumor cells; a special type of laser light activates the drug to attack the tumor. Iron oxide is a contrast agent used to enhance magnetic resonance imaging, or MRI.

"Photofrin goes into tumor blood vessels and collapses the vasculature, which then starves the tumor of the blood flow needed to survive. The problem with free photofrin treatment is that it can cause damage to healthy tissue. In our study, the nanoparticle becomes a vehicle to deliver the drug directly to the tumor," says study author Brian Ross, Ph.D., professor of radiology at the U-M Medical School and co-director of Molecular Imaging at the U-M Comprehensive Cancer Center.

Photofrin has been used to treat several types of cancer, including esophageal, bladder and skin cancers. It works by traveling through blood vessels until it reaches the vessels supplying blood to the tumor. When activated by light, the Photofrin collapses these blood vessels, starving the tumor of the blood it needs to survive.........

Posted by: Janet      Permalink         Source


November 13, 2006, 9:06 PM CT

Where Chimp And Human Brains Diverge

Where Chimp And Human Brains Diverge
Six million years ago, chimpanzees and humans diverged from a common ancestor and evolved into unique species. Now UCLA researchers have identified a new way to pinpoint the genes that separate us from our closest living relative and make us uniquely human. The Proceedings of the National Academy of Sciences reports the study in its Nov. 13 online edition.

"We share more than 95 percent of our genetic blueprint with chimps," explained Dr. Daniel Geschwind, principal investigator and Gordon and Virginia MacDonald Distinguished Professor of Human Genetics at the David Geffen School of Medicine. "What sets us apart from chimps are our brains: homo sapiens means 'the knowing man.'

"During evolution, changes in some genes altered how the human brain functions," he added. "Our research has identified an entirely new way to identify those genes in the small portion of our DNA that differs from the chimpanzee's." .

By evaluating the correlated activity of thousands of genes, the UCLA team identified not just individual genes, but entire networks of interconnected genes whose expression patterns within the brains of humans varied from those in the chimpanzee.

"Genes don't operate in isolation each functions within a system of related genes," said first author Michael Oldham, UCLA genetics researcher. "If we examined each gene individually, it would be similar to reading every fifth word in a paragraph you don't get to see how each word relates to the other. So instead we used a systems biology approach to study each gene within its context." .........

Posted by: Daniel      Permalink         Source


November 10, 2006, 5:12 AM CT

Memories: It's All In The Packaging

Memories: It's All In The Packaging
Scientists at UC Irvine have observed that how much detail one remembers of an event depends on whether a certain portion of the brain is activated to "package" the memory.

The research may help to explain why sometimes people only recall parts of an experience such as a car accident, and yet vividly recall all of the details of a similar experience.

In experiments using functional magnetic resonance imaging (fMRI), the researchers were able to view what happened in the brains of subjects when they experienced an event made up of multiple contextual details. They observed that participants who later remembered all aspects of the experience, including the details, used a particular part of the brain that bound the different details together as a package at the time the event occurred. When this brain region wasn't activated to bind together the details, only some aspects of an event were recalled. The findings are reported in the current issue of Neuron.

"This study provides a neurological basis for what psychology experts have been telling us for years," said Michael Rugg, director of UCI's Center for the Neurobiology of Learning and Memory and senior author of the paper. "You can't get out of memory what you didn't put into it. It is not possible to remember things later if you didn't pay attention to them in the first place".........

Posted by: Daniel      Permalink         Source


November 8, 2006, 8:55 PM CT

Gene Therapy Inhibits Epilepsy

Gene Therapy Inhibits Epilepsy
For the first time, scientists have inhibited the development of epilepsy after a brain insult in animals. By using gene treatment to modify signaling pathways in the brain, neurology scientists observed that they could significantly reduce the development of epileptic seizures in rats.

"We have shown that there is a window to intervene after a brain insult to reduce the risk that epilepsy will develop," said one of the lead researchers, Amy R. Brooks-Kayal, M.D., a pediatric neurologist at The Children's Hospital of Philadelphia and associate professor of Neurology and Pediatrics at the University of Pennsylvania School of Medicine. "This provides a 'proof of concept' that altering specific signaling pathways in nerve cells after a brain insult or injury could provide a scientific basis for treating patients to prevent epilepsy".

Dr. Brooks-Kayal and Shelley J. Russek, Ph.D., of Boston University School of Medicine were senior authors of the study in the Nov. 1 Journal of Neuroscience.

Working in a portion of the brain called the dentate gyrus, the scientists focused on one type of cell receptor, type A receptors, for the neurotransmitter gamma-aminobutyric acid (GABA). When GABA(A) receptors are activated, they inhibit the repetitive, excessive firing of brain cells that characterizes a seizure. Seizures are thought to occur, at least in part, because of an imbalance between two types of neurotransmitters: the glutamate system, which stimulates neurons to fire, and the GABA system, which inhibits that brain activity.........

Posted by: Daniel      Permalink         Source


November 7, 2006, 11:14 PM CT

Gene Shapes Brain Region

Gene Shapes Brain Region Researchers led by Dr. Dwight German, professor of psychiatry, have discovered that a gene variant linked to mental illness is associated with enlargement of a brain region that handles negative emotions.
A gene variant linked to mental illness goes hand-in-hand with enlargement of a brain region that handles negative emotions, scientists at UT Southwestern Medical Center and the Central Texas Veterans Health Care System have found.

The region of the brain called the pulvinar is larger and contains more nerve cells in humans who carry the gene.

"This might indicate that the brain regions that receive input from the pulvinar are more strongly influenced in such individuals, and the pulvinar communicates with brain regions involved in negative emotional issues," said Dr. Dwight German, professor of psychiatry at UT Southwestern and senior author of a study available online and in a future issue of Biological Psychiatry

The scientists focused on a gene correlation to the neurotransmitter serotonin, one of the chemical messengers that nerves use to communicate with one another. Once specific nerve cells release serotonin, a molecule called the serotonin transporter (SERT) brings it back into the cell. Thus, serotonin has only a brief influence on the target neurons. Drugs that prevent this re-uptake, such as Prozac, are frequently used to treat patients with depression.

The serotonin transporter gene has two forms, or variants: short, or SERT-s, and long, SERT-l. A person can have two copies of the short gene, one copy each of the short and long, or two copies of the long gene. It is estimated that about 17 percent of the population has two copies of the SERT-s gene.........

Posted by: Daniel      Permalink         Source



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Did you know?
The drug Ativan is better than Valium or Dilantin for controlling severe epileptic seizures, according to a new review of studies.Ativan, or lorazepam, and Valium, or diazepam, are both benzodiazepines, the currently preferred class of drugs for treating severe epileptic seizures. Dilantin, or phenytoin, is an anticonvulsant long used for the treatment of epileptic seizures.

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