In studies involving more than 35,000 people and a survey across the entire human genome, an international team supported in part by the National Institutes of Health (NIH) has found evidence that common genetic variants recently linked to osteoarthritis may also play a minor role in human height. The findings were released in Nature Genetics.
The variants most strongly associated with height in the new genome-wide association study lie in a region of the human genome thought to influence expression of a gene for growth differentiation factor 5 (GDF5), which is a protein involved in the development of cartilage in the legs and other long bones.
A team of researchers at Penn Sate has used an animal model to reveal, for the first time, a physiological basis for the effect of alcohol on male sexual behavior, including increased sexual arousal and decreased sexual inhibition.
The research in PLoS ONE resulted in four novel findings with broad importance for further addiction research. It is the first study to characterize the effects of chronic alcohol exposure in fruit flies. "Physiological evidence supporting various theories about the effect of alcoholic drinks has been lacking, so our now having a suitable animal model makes it possible to conduct much-needed laboratory research on this issue," explains research-team-leader Kyung-An Han, associate professor of biology and a neuroscientist at Penn State.
It's good news that we are living longer, but bad news that the longer we live, the better our odds of developing late-onset Alzheimer's disease.
Alzheimer's is a debilitating neurodegenerative disease that causes memory loss, dementia, personality change and ultimately death. The national Alzheimer's Association estimates that 5.1 million Americans are currently afflicted with the disease and predicts that the number may increase to between 11 million and 16 million people by the year 2050.
Many Alzheimer's researchers have long touted fish oil, by pill or diet, as an accessible and inexpensive "weapon" that may delay or prevent this debilitating disease.
The melodious sound of a songbird may appear effortless, but his elocutions are actually the result of rigorous training undergone in youth and maintained throughout adulthood. His tune has virtually “crystallized” by maturity. The same control is seen in the motor performance of top athletes and musicians. Yet, subtle variations in highly practiced skills persist in both songbirds and humans. Now, scientists think they know why.
Their finding, reported in the current issue of “Nature,” suggests that natural variation is a built-in mechanism designed to allow the nervous system to explore various subtle options aimed at maintaining and optimizing motor skills in the face of such variables as aging and injury.
Did you know even bacteria get old? Scientists traditionally assumed that bacteria were immortal, since these single-celled organisms split into two apparently identical daughter cells, which in turn divide, and so on. We now believe that this is not true.
Eric Stewart of Northeastern University, and his colleagues took fluorescent images of individual E. coli cells over ten generations. Each generation the E. coli cells divide down the middle, giving each daughter cell one new tip and an old tip from its mother, or grandmother, or some older ancestor.
No human can survive longer than a few minutes underwater, and even a well-trained Olympic swimmer needs frequent gulps of air. Our brains need a constant supply of oxygen, particularly during exercise.
Contrast that with Weddell seals, animals that dive and hunt under the Antarctic sea ice. They hold their breath for as long as 90 minutes, and remain active and mentally alert the whole time. The seals aren't fazed at all by low levels of oxygen that would cause humans to black out.
Long-lived, wild animals harbor genetic differences that influence how quickly they begin to show their age, according to the results of a long-term study reported in Current Biology. Evidence for the existence of such genetic variation for aging rates—a central tenet in the evolutionary theory that explains why animals would show physiological declines as they grow older—had largely been lacking in natural populations until now, the researchers said.
“We’ve found that individuals differ in their rates of aging, or senescence, and that these differences are (at least in part) caused by genetic effects so they will be inherited,” said Alastair Wilson of the University of Edinburgh.
Research has shown convincing evidence that dietary patterns practiced during adulthood are important contributors to age-related cognitive decline and dementia risk. An article published in Annals of the New York Academy of Sciences highlights information on the benefits of diets high in fruit, vegetables, cereals and fish and low in saturated fats in reducing dementia risk.
Adults with diabetes are especially sensitive to the foods they eat with respect to cognitive function. Specifically, an adult with diabetes will experience a decline in memory function after a meal, especially if simple carbohydrate foods are consumed.
An age-related decline in heart function is a risk factor for heart disease in the elderly. While many factors contribute to a progressive age-related decline in heart function, alterations in the types of fuels the heart uses to produce energy also play important roles.
Jason Dyck and his research team at the University of Alberta have been studying the types of fuels used by the heart in young and aged mice. The young healthy heart normally used a balance of fat and sugar to generate energy to allow the heart to beat and pump blood efficiently. However, as the heart ages the ability to use fat as an energy source deteriorates. This compromises heart function in the elderly.
In a new study, mice with brain injuries experienced enhanced memory -- similar to the level found in healthy mice -- up to three months after receiving a stem cell treatment. Scientists believe the stem cells secreted proteins called neurotrophins that protected vulnerable cells from death and rescued memory. This creates hope that a drug to boost production of these proteins could be developed to restore the ability to remember in patients with neuronal loss.
“Our research provides clear evidence that stem cells can reverse memory loss,” said Frank LaFerla, professor of neurobiology and behavior at UCI.