Archive for January 2010
Many of the health benefits of aerobic exercise are due to the most recent exercise session (rather than weeks, months and even years of exercise training), and the nature of these benefits can be greatly affected by the food we eat afterwards, according to a study published in the Journal of Applied Physiology (http://jap.physiology.org).
“Differences in what you eat after exercise produce different effects on the body’s metabolism,” said the study’s senior author, Jeffrey F. Horowitz of the University of Michigan. This study follows up on several previous studies that demonstrate that many health benefits of exercise are transient: one exercise session produces benefits to the body that taper off, generally within hours or a few days. Read the rest of this entry »
Investigators at Sanford-Burnham Medical Research Institute (Sanford-Burnham) have discovered a new way the cell surface protein, CD44, helps specific T helper (Th1) cells develop immunologic memory. Linda Bradley, Ph.D., Bas Baaten, Ph.D., and colleagues determined that without CD44, Th1 cells died off during their initial immune response and were unable to generate immunologic memory. This is the first time scientists have identified this unique CD44 function on Th1 cells, making the protein a potential target to treat a variety of diseases. The study was published online on January 14 in the journal Immunity. Read the rest of this entry »
The antiaging power of blood might not be just the stuff of vampire stories. According to new research from Harvard University, an unspecified factor in the blood of young mice can reverse signs of aging in the circulatory system of older ones. It’s not yet clear how these changes affect the animals’ overall health or longevity. But the research provides hope that some aspects of aging, such as the age-related decline in the ability to fight infection, might be avoidable. Read the rest of this entry »
Posted January 30, 2010on:
Ever since Cicero’s De Natura Deorum ii.34., humans have been intrigued by the origin and mechanisms underlying complexity in nature. Darwin suggested that adaptation and complexity could evolve by natural selection acting successively on numerous small, heritable modifications. But is this enough? Here, we describe selected studies of experimental evolution with robots to illustrate how the process of natural selection can lead to the evolution of complex traits such as adaptive behaviours. Just a few hundred generations of selection are sufficient to allow robots to evolve collision-free movement, homing, sophisticated predator versus prey strategies, coadaptation of brains and bodies, cooperation, and even altruism. In all cases this occurred via selection in robots controlled by a simple neural network, which mutated randomly
Children exposed in the womb to chemicals in cosmetics and fragrances are more likely to develop behavioral problems commonly found in children with attention deficit disorders, according to a study of New York City school-age children published Thursday.
Scientists at Mount Sinai School of Medicine reported that mothers who had high levels of phthalates during their pregnancies were more likely to have children with poorer scores in the areas of attention, aggression and conduct.
Children were 2.5 times more likely to have attention problems that were “clinically significant” if their mothers were among those highest exposed to phthalates, the study found. The types of behavior that increased are found in children with Attention Deficit Hyperactivity Disorder and other so-called disruptive behavior disorders.
C. elegans, a tiny worm about a millimeter long, doesn’t have much of a brain, but it has a nervous system — one that comprises 302 nerve cells, or neurons, to be exact. In the 1970s, a team of researchers at Cambridge University decided to create a complete “wiring diagram” of how each of those neurons are connected to one another. Such wiring diagrams have recently been christened “connectomes,” drawing on their similarity to the genome, the total DNA sequence of an organism. The C. elegans connectome, reported in 1986, took more than a dozen years of tedious labor to find.
Now a handful of researchers scattered across the globe are tackling a much more ambitious project: to find connectomes of brains more like our own. The scientists, including several at MIT, are working on technologies needed to accelerate the slow and laborious process that the C. elegans researchers originally applied to worms. With these technologies, they intend to map the connectomes of our animal cousins, and eventually perhaps even those of humans. Their results could fundamentally alter our understanding of the brain.
via Mapping the brain.