Climate Change Linked to Population Shifts Among Mammals

Scientists have shown, for the first time, that changes in a large-scale climate system can synchronize population fluctuations in multiple mammal species across a continent-scale region. The study, to be published in the 14 November 2002 issue of the journal Nature, compares long-term data on the climate system known as the North Atlantic Oscillation with long-term data from Greenland on the population dynamics of caribou and muskoxen, which are large mammals adapted to breeding in the Arctic.

Causes of Life-Expectancy Gap Between Races, Education Levels ID’d

Researchers for the first time have identified and ranked which diseases contribute most to the life-expectancy gap between races and between education levels. The top four contributors to the life-expectancy disparity between blacks and whites are hypertension, HIV, homicide and diabetes. The top six contributors of mortality differences between education levels are all smoking-related diseases.

Dietary vitamin E associated with sharply lower risk of Parkinson’s

Previous research has implicated oxidative damage (cell degradation) in the development of Parkinson’s disease. Because vitamins E, C and carotenoids are antioxidants, researchers recently studied the associations between their intake and risk of Parkinson’s disease. Their conclusions point not to supplements, but to dietary intake of vitamin E (from the foods we eat) as having a protective factor in the risk of developing Parkinson’s disease. The study is reported in the October 22 issue of Neurology, the scientific journal of the American Academy of Neurology.

One in Three Children Regularly Exposed to Tobacco Smoke at Home

Second-hand tobacco smoke threatens the health of 21 million American children ? 35 percent of everyone age 17 and younger ? who live in homes where residents or visitors smoke once a week or more, according to a study published Nov. 13 by researchers from RAND and UCLA. The study is the most thorough ever conducted of youths’ exposure to environmental second-hand tobacco smoke at home. It found that 19 million American children ? 28 percent of everyone in the United States 17 and younger ? are exposed to tobacco smoke at home on a daily basis.

Scientists Eavesdrop on Cellular Conversations by Making Mice ‘Glow’

Scientists have coupled the protein that makes fireflies glow with a device similar to a home video camera to eavesdrop on cellular conversations in living mice. The team’s research will allow scientists to study how cellular proteins talk to one another. These communications trigger changes that regulate a healthy body and cause disease when the signals go awry. The findings may speed development of new drugs for cancer, cardiovascular diseases and neurological diseases.

Exceptionally Bright Eruption on Io Rivals Largest in Solar System

Routine monitoring of volcanic activity on Jupiter’s moon Io has turned up the largest eruption to date on Io’s surface or in the solar system. The eruption took place in February 2001, though image analysis was only recently completed by a team of University of California, Berkeley, astronomers. Their results are published in the November issue of the planetary sciences journal Icarus. “The Surt eruption appears to cover an area of 1,900 square kilometers, which is larger than the city of Los Angeles and even larger than the entire city of London,” said the lead researcher. “The total amount of energy being released by the eruption is amazingly high, with the thermal output from this one eruption almost matching the total amount of energy emitted by all of the rest of Io, other volcanoes included.”

New HIV Vaccine Aims for Global Effectiveness

Clinical tests began today of a novel vaccine directed at the three most globally important HIV subtypes, or clades. Developed by scientists at the Dale and Betty Bumpers Vaccine Research Center, part of the National Institute of Allergy and Infectious Diseases, the vaccine incorporates HIV genetic material from clades A, B and C, which cause about 90 percent of all HIV infections around the world. “This is the first multigene, multiclade HIV vaccine to enter human trials,” said NIAID Director Anthony S. Fauci, M.D. “It marks an important milestone in our search for a single vaccine that targets U.S. subtypes of HIV as well as clades causing the global epidemic.”

Half of older adults with high blood pressure don’t have it under control

At least half of older adults with hypertension do not have their blood pressure controlled to normal levels, according to a survey of 5,888 patients around the country. The failure to control blood pressure to less than 140/90 mmHg may account for as much as 22 percent of myocardial infarctions and 34 percent of strokes in older adults, according to University of Washington researchers.

Choreography, not molecular prepattern, creates vertebrate building blocks

In a study that combines state-of-the-art biological imaging with gene expression analysis, scientists at the California Institute of Technology have uncovered a fundamental insight into the way embryonic cells and tissue move about to form key structures along the vertebrate axis. The study, which could lead to a better understanding of human development, takes advantage of the accessibility of chick embryos to embryonic manipulation. The study enters on segments known as somites, which form along either side of the future spinal cord of an embryo. Somites give rise to mature structures such as ribs, individual vertebrae, and even skin. The key role of somite segmentation in the patterning of the nervous system and the vertebral column has been long known. But the question of precisely how an individual somite buds off from a block of tissue in a pattern that is repeated all along the animal’s torso, from head to tail, is poorly understood.

Hormones Important In Female Athletic Competition

A new study has found that women athletes get far more pumped up before and during athletic competition than their male counterparts. Pre-event testosterone levels rise 9 percent, on avergae, in males whereas in females they increase by 24 percent. During the game itself women increase their testosterone production by 49 percent while in males, it increases on average 15 percent. The rise in testosterone that accompanies competition is thought to make the individual more willing to take risks, improves psychomotor function and coordination, and increase cognitive performance qualities that are very important in winning.

Researchers link teen sex to early friendships

The nature of preteen friendships can play a key role in determining whether or not a child will engage in sexual activity early in adolescence, a new study suggests. For example, researchers found that boys who had mostly female friends when they were preteens were more likely to have had sex by age 16 than were other boys. However, the same wasn’t true for girls who as preteens had mostly male friends.

Pain May Come with Gain in Childhood Exercise

The phrase “no pain, no gain,” used by coaches to prod school-age athletes, may have more meaning than they ever imagined, two studies have found. The studies appear in the October issues of Pediatrics and Pediatric Research and suggest new ways to mark the boundary between healthy and unhealthy exercise. The research also may help physicians and others develop optimal levels of exercise that may help stave off the current epidemic of obesity in adults and children.