June 14, 2006, 11:48 PM CT

Pesticide Use Increases Risk Of Parkinson Disease

Mayo Clinic scientists have found that using pesticides for farming or other purposes increases the risk of developing Parkinson's disease for men. Pesticide exposure did not increase the risk of Parkinson's in women, and no other household or industrial chemicals were significantly linked to the disease in either men or women.

Findings would be reported in the recent issue of the journal Movement Disorders.

"This confirms what has been found in prior studies: that occupational or other exposure to herbicides, insecticides and other pesticides increases risk for Parkinson's," says Jim Maraganore, M.D., Mayo Clinic neurologist and study investigator. "What we think may be happening is that pesticide use combines with other risk factors in men's environment or genetic makeup, causing them to cross over the threshold into developing the disease. By contrast, estrogen may protect women from the toxic effects of pesticides."

The researchers identified all those in Olmsted County, Minn., home of Mayo Clinic, who had developed Parkinson's disease between 1976 and 1995. Each person with Parkinson's disease was matched for comparison to someone similar in age and gender who did not have the disease. The scientists conducted telephone interviews with 149 of those with Parkinson's and 129 of those who did not have the disease, or a proxy for these people, to assess exposure to chemical products via farming occupation, non-farming occupation or hobbies. The researchers were unable to determine through these interviews the exact exposure levels of these individuals or the cumulative lifetime exposure to pesticides.........

Posted by: Daniel      Permalink         Source

June 13, 2006, 11:40 PM CT

Link Between Obesity And Memory

Researchers have wondered why obese patients who have diabetes also may have problems with their long-term memory. New Saint Louis University research in this month's Peptides provides a clue.

"Leptin is a hormone secreted by fat cells that tells us to stop eating. In obese people, it doesn't cross into the brain to help regulate appetite," says Susan A. Farr, Ph.D., principal investigator and associate research professor in the division of geriatric medicine at Saint Louis University School of Medicine.

"We've now found leptin affects the brain in other ways, compromising learning and memory. Low levels of leptin also could be correlation to cognitive deficits in disorders like type two diabetes."

Farr and her research team tested the role of leptin in learning and memory using an animal model. They found that mice navigated a maze better after they received leptin.

"We found that this drug affected the processes going into the brain," says Farr, who also is a researcher at Veterans Affairs Medical Center in St. Louis. "The mice that got the drug at the appropriate dose had improved learning and long-term memory."

Mice with elevated levels of amyloid-beta protein, the brain plaques believed to cause Alzheimer's disease, and impaired learning and memory were "super sensitive" to leptin, Farr adds.........

Posted by: JoAnn      Permalink         Source

June 13, 2006, 9:45 PM CT

Child Abuse Can Cause Schizophrenia

University of Manchester researcher Paul Hammersley is to tell two international conferences, in London and Madrid on 14 June 2006, that child abuse can cause schizophrenia.

The groundbreaking and highly contentious theory, co-presented by New Zealand clinical psychology expert Dr John Read, has been described as "an earthquake" that will radically change the psychiatric profession.

Clinical psychology expert and writer Dr Oliver James commented: "The psychiatric establishment is about to experience an earthquake that will shake its intellectual foundations [and] may trigger a landslide."

Mr Hammersley, Programme Director for the COPE (Collaboration of Psychosocial Education) Initiative at the School of Nursing Midwifery and Social Work, said: "We are not returning to the 1960s and making the mistake of blaming families, but professionals have to realize that child abuse was a reality for large numbers of adult sufferers of psychosis."

He added: "We work very closely in collaboration with the Hearing Voices Network, that is with the people who hear voices in their head. The experience of hearing voices is consistently associated with childhood trauma regardless of diagnosis or genetic pedigree."

Dr Read said: "I hope we soon see a more balanced and evidence-based approach to schizophrenia and people using mental health services being asked what has happened to them and being given help instead of stigmatizing labels and mood-altering drugs."........

Posted by: Janet      Permalink         Source

June 13, 2006, 9:22 PM CT

Asherman's Syndrome Poses Pregnancy Problems

A somewhat rare condition could cause significant problems for women trying to become pregnant. Asherman's syndrome affects the walls of the uterus, which stick together as a result of scar tissue following surgery. Asherman's, which may occur following a D&C (dilatation and curettage, a procedure to scrape and collect the tissue in the uterus), may causes problems for a woman trying to get pregnant or carry one full term.

As per Dr. Fermin Barrueto, Chief of Endoscopy and Pelvic Reconstruction at Mercy, mild to moderate cases of Asherman's syndrome can mean reduced menstrual flow and frequent miscarriage. When Asherman's syndrome becomes severe, he said menstrual flow completely stops and there's no pregnancy. "The great majority don't even know they have this condition and there is a lack of space for baby to grow," Barrueto said.

Significant research brought Brenner to Barrueto in an effort fix her condition with surgery -- a very delicate operation.

"What we have to do is put a telescope inside the uterus and make a new cavity, it has to be done under laproscopic control," Barrueto said.

Barreuto said the most common scenarios for Asherman's syndrome to occur is after a postpartum dilatation and curettage, or sometimes after having fibroids removed.........

Posted by: Emily      Permalink         Source

June 12, 2006, 11:37 PM CT

A Sweet Solution For Alzheimer's Disease?

Certain variants of a simple sugar ameliorate Alzheimer's-like disease in mice, as per a new study by Canadian researchers. Eventhough the new studies are still in the early stages, the findings could lead to new therapies that prevent or delay the onset of Alzheimer's disease.

The new studies show that some types of a sugar called cyclohexanehexol-also known as inositol-prevented the accumulation of amyloid ß deposits, a hallmark of Alzheimer's disease. Scyllo-inositol therapy also improved cognitive abilities in the mice and allowed them to live a normal lifetime. The study appeared in advance online publication of the journal Nature Medicine on June 11, 2006.

HHMI international research scholar and senior author Peter St George-Hyslop cautioned that the chemicals tested in these studies are not the type of inositol sold commercially as a nutritional supplement. That type-myo-inositol-has been shown previously to be ineffective at breaking up amyloid aggregates, he said.

In the brain of a person with Alzheimer's disease, small proteins called amyloid ß aggregate into plaques, and a protein called tau clumps into neurofibrillary tangles. The brain becomes inflamed and neurons atrophy and die. It's not completely clear what kind of amyloid ß peptide (monomers, oligomeric aggregates, or fibrillar aggregates) is responsible for the onset of disease, said St George-Hyslop of the University of Toronto. "Because we were able to show that scyllo-inositol specifically dispersed the high-molecular-weight oligomeric aggregates, this study confirms that the initiating event is the accumulation of oligomeric aggregates of amyloid ß peptide," he said.........

Posted by: Daniel      Permalink         Source

June 10, 2006, 7:00 PM CT

Migraine Headaches And Sexual Desire

Contrary to the popular cliche, "Not tonight, I have a headache," new research suggests that not all headache sufferers avoid sexual activity. In fact, migraine sufferers reported higher levels of sexual desire than those with other types of headaches, as per scientists from Wake Forest University School of Medicine and his colleagues.

"Our study suggests that sexual desire and migraine headaches may be influenced by the same brain chemical," said Timothy Houle, Ph.D., lead author and research assistant professor of anesthesiology. "The results support the idea that migraine, as a syndrome, is associated with other common phenomena. Understanding of this link will help us to better understand the nature of migraine and perhaps lead to improved therapy."

The research, involving 68 young adults from Chicago, will appear in an upcoming issue of Headache, published by the American Headache Society, and already is available on line.

The objective of the study was to examine the relationship between migraine headache and self-reported sexual desire. There is evidence of a complex relationship between sexual activity and headache. Both sexual desire and migraine headache have been linked to levels of serotonin, a brain chemical that also plays a role in depression. An excess of serotonin may be associated with decreased libido, and migraine sufferers are reported to have low system levels of the brain chemical. Serotonin has also been found to play a role in migraine attacks.........

Posted by: Janet      Permalink         Source

June 8, 2006, 7:23 PM CT

Sugar Required For Healthy Brain Development

New approaches to preventing birth defects from a rare metabolic disorder could result from research completed at Washington University School of Medicine in St. Louis. The findings also may have implications for patients with neurodegenerative diseases such as Parkinson's.

To learn more about how glucose affects human development, Mary Carayannopoulos, Ph.D., instructor in pediatrics, developed the first vertebrate model of glucose homeostasis and embryonic development using the zebrafish. Their transparent embryos develop similarly to humans, except that they grow outside of the mother's body, where development can be more easily observed. The model provides the foundation for and insight into the roles of nutrition and genetics in human birth defects.

Carayannopoulos used the zebrafish model to study Glut1 deficiency. Glut1 is a protein that transports glucose in cerebrospinal fluid to the brain. Glut1 deficiency syndrome in humans is linked to microcephaly, epilepsy, developmental delays and other neurologic abnormalities.

Results of the study appear in the recent issue of the Journal of Biological Chemistry, but are available now online. Penny J. Jensen, Ph.D., staff scientist in the Department of Pediatrics, was lead author of the study.

Carayannopoulos lowered Glut1 levels in the zebrafish embryo. Over 72 hours of observing the developing fish, she found that Glut1 deficiency led to cell death in the brain, which uses glucose as its energy source. When injecting the zebrafish with another protein, Bad, which normally activates cell death, the Glut1 and Bad seemed to cancel each other out, correcting brain defects and promoting cell survival.........

Posted by: Daniel      Permalink         Source

June 8, 2006, 7:19 PM CT

Role Of Central Nervous System In MS-like Disease

It may sound like a case of blame the victim, but scientists at Washington University School of Medicine in St. Louis have shown that cells in the central nervous system can sometimes send out signals that invite hostile immune system attacks. In mice the scientists studied, this invitation resulted in damage to the protective covering of nerves, causing a disease resembling multiple sclerosis.

"It's been clear for quite a while that our own lymphocytes (white blood cells) have the ability to enter the central nervous system and react with the cells there," says John Russell, Ph.D., professor of molecular biology and pharmacology. "Under normal circumstances, the brain and the immune system cooperate to keep out those cells that might harm the brain. But in people with multiple sclerosis, they get in."

The scientists found that they could prevent destructive immune cells from entering nervous system tissue by eliminating a molecular switch that sends "come here" messages to immune cells. Ordinarily, flipping that switch would cause immune cells to rush to the vicinity of the cells that sent the signals and destroy whatever they consider a danger - including nerve cell coatings.

But in the mice in which the switch was removed, the scientists saw that immune cells previously primed by the researchers to attack the central nervous system (CNS) did not enter the CNS, and the mice stayed healthy.........

Posted by: Daniel      Permalink         Source

June 8, 2006, 7:15 PM CT

Erotic Images Elicit Strong Response From Brain

A new study suggests the brain is quickly turned on and "tuned in" when a person views erotic images.

Scientists at Washington University School of Medicine in St. Louis measured brainwave activity of 264 women as they viewed a series of 55 color slides that contained various scenes from water skiers to snarling dogs to partially-clad couples in sensual poses.

What they found may seem like a "no brainer." When study volunteers viewed erotic pictures, their brains produced electrical responses that were stronger than those elicited by other material that was viewed, no matter how pleasant or disturbing the other material may have been. This difference in brainwave response emerged very quickly, suggesting that different neural circuits may be involved in the processing of erotic images.

"That surprised us," says first author Andrey P. Anokhin, Ph.D., research assistant professor of psychiatry. "We believed both pleasant and disturbing images would evoke a rapid response, but erotic scenes always elicited the strongest response."

As subjects looked at the slides, electrodes on their scalps measured changes in the brain's electrical activity called event-related potentials (ERPs). The scientists learned that regardless of a picture's content, the brain acts very quickly to classify the visual image. The ERPs begin firing in the brain's cortex long before a person is conscious of whether they are seeing a picture that is pleasant, unpleasant or neutral.........

Posted by: Daniel      Permalink         Source

June 5, 2006, 11:19 PM CT

New Way to Fight Brain Cancer

Taking advantage of a large assortment of chemical inhibitors produced by the pharmaceutical industry as potential drugs, Howard Hughes Medical Institute scientists have synthesized and characterized a panel of compounds that may lead to new therapy strategies for targeting glioblastoma, a common type of brain tumor that commonly thwarts therapy. The compounds have also revealed new information about insulin signaling, and could be a powerful tool to evaluate cellular enzymes as potential targets for drug design.

The work is detailed in two papers reported in the journals Cell and Cancer Cell. HHMI investigator Kevan M. Shokat at the University of California, San Francisco, is the senior author on the Cell paper, published on-line April 27, 2006, which describes a pharmacological map of the family of enzymes known as PI3-kinases. Zachary A. Knight, an HHMI predoctoral fellow in Shokat's lab, is the first author of the study, which was conducted in collaboration with colleagues from UCSF. The second paper, reported in the May 15, 2006, issue of the journal Cancer Cell, describes the effects of inhibiting these kinases in glioblastoma cells. Shokat and Knight collaborated on the Cancer Cell paper with senior author William A. Weiss at UCSF.

Researchers have devoted a great deal of research to kinases because they may provide the key to better understanding of a wide array of fundamental biological processes. Kinases are a huge family of enzymes that regulate intracellular communication by tagging key molecules with a small, energy-packed chemical group known as a phosphate. Their influence over processes ranging from cell growth and survival to learning and memory makes kinases desirable targets for new drugs, and progress in this area of research depends on the careful definition of the roles of individual enzymes.........

Posted by: Daniel      Permalink         Source