Conflict between mates means uglier offspring. JOHN WHITFIELD Parental bickering damages young birds. Mother finches do less work when a father is around and their sons are less attractive to females as a consequence, researchers have discovered. Each mate plays a game of 'evolutionary poker', trying to invest as little as it can get away with. "Parents hold back a bit in the hope that the other will make up the shortfall," says ecologist Ian Hartley of Lancaster University, UK. This is the first time that such gambling has been shown to damage offspring. A female zebra finch (Taeniopygia guttata ) raising two chicks alone does more work than a paired mother with a brood of four, Hartley and his colleagues found. Males reared in one- and two-parent families were of similar size and weight, but, given the choice, females plumped for single-parented males more often. * Royle, N.J., Hartley, I.R. & Parker, G.A. Sexual conflict reduces offspring fitness in zebra finches. Nature, 416, 733 - 736, (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Keyword: Sexual Behavior; Evolution
Link ID: 1906 - Posted: 06.24.2010

Field Museum scientist challenges accepted theories, dating methods CHICAGO - New research that accounts for gaps in the fossil record challenges traditional methods of interpreting fossils and constructing evolutionary trees. Applying a new statistical approach to primates demonstrates that this group-from which humans developed-originated 85 million years ago (Mya) rather than 65 Mya, as is widely accepted. This revision has implications throughout the evolutionary tree of primates, including the time of origin of the human lineage. Key findings from the new approach to interpreting the fossil record include: * Primates originated while dinosaurs still roamed the earth. This challenges the widely accepted theory that primates could not establish a foothold until the end of the Cretaceous (65 Mya) when an asteroid cleared the way by hitting the earth and wiping out dinosaurs. * If times of divergence within the primate tree are revised accordingly, it is likely that the divergence of humans from chimps occurred about 8 Mya rather than 5 Mya.

Keyword: Evolution
Link ID: 1905 - Posted: 04.18.2002

Emory researchers study the possibilities of a common, unrecognized comorbidity Emory University researchers may have found a common but heretofore unrecognized link between low testosterone levels and certain non-motor symptoms (fatigue, depression, anxiety or sexual dysfunction) in male Parkinson’s disease (PD) patients. When given testosterone replacement therapy (TRT), the researchers report that patients with low levels of testosterone experienced significant improvement in these symptoms, which had not responded to other medications. But investigators caution they only looked at a small group of five patients and they did not compare those people to a placebo or control group. Michael Okun, M.D., and Mahlon DeLong, M.D., in the Department of Neurology, as well as William McDonald, M.D., in the Department of Psychiatry and Behavioral Sciences will present their findings at the American Academy of Neurology 54th Annual Meeting in Denver, Colo., on April 17. The researchers will also publish their work in an upcoming issue of the Archives of Neurology.

Keyword: Parkinsons; Hormones & Behavior
Link ID: 1904 - Posted: 06.24.2010

By Julia Sommerfeld MSNBC DENVER, — Experimental transplants of cells from aborted fetuses and donated eyes are showing promise for the treatment of Parkinson’s disease, according to two studies out Wednesday. Both types of cells were shown to survive in patients’ brains and improve some of the hallmark symptoms of the dreaded disease. PARKINSON’S, which affects an estimated 1 million people in the United States, is caused when the brain cells that produce a chemical known as dopamine die off. Colorado researchers reported follow-up results on a controversial experiment in which holes were drilled in the skull and dopamine cells from aborted fetuses were implanted in the brains of advanced Parkinson’s patients. Other doctors described the initial results of transplants of dopamine cells from the retinas of donated eyes. Both findings were presented at the annual meeting of the American Academy of Neurology in Denver. “It takes the loss of 80 percent to 90 percent of dopamine-producing neurons to lead to the symptoms of Parkinson’s disease,” said Dr. Robin Brey, a professor of medicine, division of neurology at University of Texas Health Sciences Center, San Antonio. “So you need fairly small amount of dopamine-producing neurons to remain normal. That tells us that even if a small number of transplanted cells were to take and produce dopamine, that could do a lot. So this is very promising.” MSNBC Terms, Conditions and Privacy © 2002

Keyword: Parkinsons; Stem Cells
Link ID: 1902 - Posted: 06.24.2010

The study is small but the results encouraging By Pallab Ghosh BBC science correspondent Doctors in Bristol, UK, have developed an experimental treatment which, they suspect, has regenerated the brains of five patients with Parkinson's disease. One patient has learned to laugh again and has regained his sense of smell. The doctors say it is too soon to tell whether the treatment is long lasting or could be used on all sufferers of Parkinson's. But they have been astonished at how effective the treatment has been so far. The treatment involves putting a drug called GDNF into a mechanical pump, which feeds it to the most damaged parts of the brain. (C) BBC

Keyword: Parkinsons; Trophic Factors
Link ID: 1901 - Posted: 04.18.2002

Being Social Is A Key Component To Creating An Enriched Environment That Stimulates Cognitive Development WASHINGTON - Toddlers who physically explore their environment, engage socially with other children and verbally interact with adults are likely to have better scholastic and reading abilities as teenagers compared to less engaging toddlers. The reason, suggest the researchers who study predictors of intelligence, is that these children create their own stimulating environment thus facilitating their own cognitive ability. These findings are reported on in the April issue of the American Psychological Association's (APA) Journal of Personality and Social Psychology. To determine this relationship between toddler's stimulation seeking behavior and later intelligence, psychologist Adrian Raine, Ph.D., of the University of Southern California and co-authors collected intelligence, cognitive and sociability measures on 1,795 children at age three. At age 11, the children's school achievement, reading ability and neuropsychological tests were evaluated and compared to the early measures. Those three-year-olds that exhibited high stimulation behaviors at age three scored 12 points higher on total IQ at age 11 compared with low stimulation seekers. The high stimulation seekers also had superior scholastic and reading abilities at age 11. Gender, ethnic group and parents' education or occupation was ruled out as influences on a child's approach to new stimuli, according to the authors. © PsycNET 2002 American Psychological Association

Keyword: Intelligence; Development of the Brain
Link ID: 1900 - Posted: 06.24.2010

Patients with severe cases of multiple sclerosis could be helped by stem cell transplants, research suggests. A small study in the US showed the treatment appeared to stabilise MS patients, whose condition had previously been deteriorating. Stem cells are the body's "master cells" and can develop into a wide variety of different cell types. About 85,000 people in the UK have MS, a degenerative disease of the central nervous system. The researchers' findings were presented to the American Academy of Neurology's 54th Annual Meeting in Denver, Colorado. (C) BBC

Keyword: Multiple Sclerosis; Stem Cells
Link ID: 1899 - Posted: 04.17.2002

Helen Briggs Australian scientists say they have created a "thinking cap" that will stimulate creative powers. The invention raises the possibility of being able to unlock one's inner genius by reawakening dormant parts of the brain. It is based on the idea that we all have the sorts of extraordinary abilities usually associated with savants. According to scientists at the Centre for the Mind in Sydney, these hidden talents can be stimulated using magnetism. The news has been given a cautious welcome by experts in the UK. Professor Allan Snyder and colleague Elaine Mulcahy say tests on 17 volunteers show their device can improve drawing skills within 15 minutes. They intend to submit their work for publication in a scientific journal. (C) BBC

Keyword: Intelligence
Link ID: 1898 - Posted: 04.17.2002

Carl T. Hall, Chronicle Science Writer A widely used herbicide has been linked for the first time to developmental defects in a species of aquatic frog, scientists report today, raising the possibility of a hidden toxic hazard in the environment. Laboratory experiments at the University of California at Berkeley suggest that even at very low levels, exposure to the common farm chemical atrazine can disrupt hormones and alter the sexual development of male African clawed frogs. "We saw a loss of male characteristics," said UC Berkeley biologist Tyrone B. Hayes, lead author of the study, which appears today in the Proceedings of the National Academy of Sciences. "As somebody who's concerned about biodiversity and environmental health, I think it's very serious. Now, we need to explore the possibility that such effects are occurring in the wild." ©2002 San Francisco Chronicle

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 1897 - Posted: 06.24.2010

The muscle destruction associated with Duchenne muscular dystrophy (DMD), the most common childhood form of muscular dystrophy, is halted in mice when supplemental amounts of a naturally occurring enzyme are added to the skeletal muscle. These results from researchers at the University of California, San Diego (UCSD) School of Medicine are published in the April 16, 2002 issue of the journal Proceedings of the National Academy of Sciences. Muscle wasting associated with DMD was inhibited after the UCSD team added an enzyme called CT GalNAc transferase to skeletal muscles in mice bred to develop DMD. Normally, CT GalNAc transferase is expressed in another area of the muscle, the neuromuscular junction, where nerves send impulses to muscle fiber. The UCSD team was able to re-position the enzyme so that it was available in the DMD-vulnerable skeletal muscle, which is the structural tissue that supports body movement. Copyright ©2001 Regents of the University of California. All rights reserved.

Keyword: Movement Disorders; Muscles
Link ID: 1896 - Posted: 06.24.2010

As a young brain develops, or as an older one learns new tricks, some connections between neurons flourish while others fade away. This crucial tuning is guided by the so-called NMDA receptor. But this same receptor unleashes deadly havoc during a stroke. A new study explains why: These Jekyll and Hyde-like properties depend on the receptor's location on nerve cells--a finding that could help the fight against brain damage resulting from stroke. One prominent feature of nerve communication is the spread of glutamate from one neuron to another. After this neurotransmitter crosses the gap--called a synapse--it stimulates receptors that pass the signal along. Yet at the same time, NMDA receptors are shaping the communication. They help nerve cells fiddle with the sensitivity of the synapse, a process known as synaptic plasticity. On a broader scale, NMDA receptors coordinate the construction of new synapses and the survival of nerve cells in the developing nervous system. Paradoxically, NMDA receptors can also convey the kiss of death: During a stroke, glutamate leaks from distressed brain cells and binds to NMDA receptors, triggering the neurons to kill themselves. That in turn leads to irreversible brain damage. --CHRISTIAN HEUSS Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Stroke
Link ID: 1895 - Posted: 06.24.2010

A new study suggests that neither tamoxifen nor estrogen has a negative impact on brain chemistry in elderly women. These findings may quell concerns about the safety of using tamoxifen to reduce breast cancer risk in elderly women, say Thomas Ernst, Ph.D., of Brookhaven National Laboratory in New York, and coworkers from the Harbor-UCLA Research and Education Institute in Torrance, Calif., in the April 17 issue of the Journal of the National Cancer Institute. Past studies have suggested that estrogens may improve brain functioning, possibly by blocking neural cell death caused by oxidation. However, some studies have suggested that tamoxifen, which blocks estrogen’s stimulatory effects in breast cancer, may block estrogen’s beneficial effects on the brain and possibly contribute to cognitive decline. The researchers found that women who had been treated with tamoxifen had lower levels of myo-inositol in the brain than the untreated women. Women who took estrogen also had lower levels of the chemical. Myo-inositol levels were lowest among women who had been treated with tamoxifen for longer periods of time.

Keyword: Hormones & Behavior
Link ID: 1894 - Posted: 06.24.2010

Researchers at Emory University and a group of international collaborators, using positron emission tomography (PET) brain imaging, have determined that a relatively new drug slows the loss of dopamine function in early stages of Parkinson’s disease (PD) compared with an older, more commonly used drug. Investigators say the drug ropinirole (brand name ReQuip ®) slows the loss of dopamine, a neurotransmitter produced by neurons in the brain that is found in steadily decreasing amounts as the disease progresses, in a more effective manner than levodopa (brand name Sinemet ®). In this trial, the progression of the loss of dopamine function was slowed by over 30 percent in participants taking ropinirole as compared with participants in a comparable stage of the disease taking levodopa.

Keyword: Parkinsons
Link ID: 1893 - Posted: 06.24.2010

Researchers also find tobacco has negative effects on motor development CLEVELAND - Scientists know the effects of cocaine on the adult brain and cardiovascular systems. Now there is a growing body of research documenting the effects of prenatal cocaine exposure on infants, which is raising public health concerns about the long-term cognitive and developmental outcomes for these children. A study published by Case Western Reserve University School of Medicine, MetroHealth Medical Center, and University Hospitals of Cleveland researchers in the April 17 issue of the "Journal of the American Medical Association," “Cognitive and Motor Outcomes of Cocaine-Exposed Infants,” looks at how prenatal cocaine exposure affects child developmental outcomes. CWRU researchers followed 415 cocaine-exposed infants born at MetroHealth Medical Center in Cleveland to determine how prenatal cocaine exposure affects child developmental outcomes. They were compared to non-exposed infants on cognitive and motor development until age 2. What they found, according to Singer, was that prenatal cocaine exposure does affect a child’s cognitive development, but not motor development. However, tobacco exposure had negative effects on motor development.

Keyword: Drug Abuse; Development of the Brain
Link ID: 1891 - Posted: 06.24.2010

Major study suggests added benefit of blockbuster cholesterol drugs By Julia Sommerfeld MSNBC DENVER, — Taking the cholesterol-lowering drugs known as statins may be good for more than the heart — it may also reduce the risk of Alzheimer’s disease, researchers reported here Tuesday. IN THE LARGEST study of statins and Alzheimer’s to date, researchers found that people who took the blockbuster cholesterol-lowering drugs were 79 percent less likely to develop Alzheimer’s than those who did not. That means, said lead author Dr. Robert Green, that patients on statins may be as much as five times less likely to develop Alzheimer’s disease, the dreaded degenerative brain disease that affects about 1 in 10 Americans over 65 and nearly half of those over 85. Green, an associate professor of neurology, genetics and epidemiology, and his colleagues at Boston University School of Medicine studied the link in more than 2,500 people at 15 medical centers over six years. The results were presented here Tuesday at the annual meeting of the American Academy of Neurology. Statins — sold under such brand names as Lipitor, Pravachol and Zocor — are taken by some 8 million Americans to lower levels of artery-clogging LDL, or “bad” cholesterol. About 4 million Americans suffer from Alzheimer’s disease. • MSNBC Terms, Conditions and Privacy © 2002

Keyword: Alzheimers
Link ID: 1889 - Posted: 06.24.2010

— Efforts to understand the most common cause of vision loss in millions of elderly people have led to the discovery of an entirely new family of chloride ion channels that are found in animals from worms to humans. In 1998, researchers showed that mutations in a gene that codes for the protein bestrophin were responsible for causing Best macular dystrophy, a hereditary disorder that strikes during childhood or early adolescence and causes impaired central vision. Until recently, the function of bestrophin has remained a mystery. Now, a collaborative team of Howard Hughes Medical Institute (HHMI) investigators at The Johns Hopkins University School of Medicine, has found that bestrophin is a chloride ion channel, a protein that forms a pore in cells through which charged ions can pass. In addition to showing that bestrophin is an ion channel, the scientists searched the human genome and the DNA sequences of other organisms and found at least three other members of this chloride ion channel family in humans, four in the fruit fly and 24 in the worm Caenorhabditis elegans. None of the proteins they found had previously had a function assigned to it. ©2002 Howard Hughes Medical Institute

Keyword: Vision; Genes & Behavior
Link ID: 1888 - Posted: 06.24.2010

Violence in sleep is much more common than previously thought, an expert has warned. Dr Peter Fenwick told a sleep conference at the Royal Society of Medicine that kicking, hitting, and putting hands round a partner's neck were the most common types of violence. The violence can stem from conditions such as sleepwalking and confusion on awakening. REM sleep disorders, where the normal paralysis of people's muscles while they sleep is switched off so people can 'act out' their dreams, can also be a cause. Dr Fenwick said US studies estimated up to four in 10 men suffering sleep disorders were aggressive, and one in seven could be seriously violent. The phenomenon is not new. Dr Fenwick, from London's Institute of Psychiatry, told the conference the tale of a knight who stabbed his friend to death in the night, which dates back to 1600. (C) BBC

Keyword: Sleep
Link ID: 1887 - Posted: 04.16.2002

By GINA KOLATA The obesity warnings are everywhere. The Centers for Disease Control and Prevention says that with 35 percent of Americans overweight and 27 percent obese, obesity "has risen at an epidemic rate during the past 20 years." In December, Dr. David Satcher, who was surgeon general, said obesity would soon succeed tobacco as the leading cause of preventable deaths in America. In California, there are calls for taxes on soft drinks. Across the country, there are demands that schools banish soda and candy machines. In Pennsylvania, one school district sent letters to parents telling them their children were too fat. Copyright 2002 The New York Times Company

Keyword: Obesity
Link ID: 1886 - Posted: 04.16.2002

By CLAUDIA DREIFUS BEDFORD, Mass. — At the elegant housing development for the elderly where the biologist Ernst Mayr lives, there are a game room, a library and a shrine to commemorate residents who have recently died. Not long ago, in a misfired joke, one of Dr. Mayr's housemates passed the shrine and asked, "Are you next for this, Mayr?" Without a blink, Dr. Mayr, emeritus professor of zoology at Harvard and one of the greatest living experts on evolution, returned: "I may be the oldest man here, but I'm not going anywhere. I still have a few books to write." Dr. Mayr, who is 97, takes long hikes in the woods behind the housing development every day; he is still producing professional papers and books with respectable sales, including his latest and 16th, "What Evolution Is" (Basic Books), which was published in October. Copyright 2002 The New York Times Company

Keyword: Evolution
Link ID: 1885 - Posted: 06.24.2010

* Children of alcoholics (COAs) tend to exhibit attention deficit disorder, hyperactive tendencies, rule breaking, and poor response to discipline. * Adult COAs tend to exhibit poor impulse control, antisocial tendencies and sensation seeking. * A new study has found that young adult COAs have a different emotional response to environmental cues than do individuals without a family history of alcoholism. * These findings may demonstrate underlying differences in brain chemistry and physiology. Research overwhelmingly indicates that children of alcoholics are more likely to develop significant alcohol problems, such as abuse or dependence, than will children of non-alcoholics. It is also well documented that both genetic and environmental factors contribute to this increased risk. Genetic or inherited factors include biologically rooted behavioral tendencies and self-regulation. For example, individuals with a family history of alcoholism tend to exhibit poor impulse control, antisocial tendencies and sensation seeking. A study in the April issue of Alcoholism: Clinical & Experimental Research has found that individuals with a positive history of alcoholism have a different emotional response to environmental cues than do individuals with a negative family history of alcoholism.

Keyword: Genes & Behavior; Drug Abuse
Link ID: 1884 - Posted: 04.16.2002