By Sandeep Ravindran Posted 09.04.2009 at 10:59 am
Brain Trauma MRIRehman T, Ali R, Tawil I, Yonas H (CC licensed)
Scientists have developed a gel that helps brains recover from traumatic injuries. It has the potential to treat head injuries suffered in combat, car accidents, falls, or gunshot wounds. Developed by Dr. Ning Zhang at Clemson University in South Carolina, the gel is injected in liquid form at the site of injury and stimulates the growth of stem cells there.
Brain injuries are particularly hard to repair, since injured tissues swell up and can cause additional damage to the cells. So far, treatments have tried to limit this secondary damage by lowering the temperature or relieving the pressure at the site of injury. However, these techniques are often not very effective.
More recently, scientists have considered transplanting donor brain cells into the wound to repair damaged tissue. This method has so far had limited results when treating brain injuries. The donor cells often fail to grow or stimulate repair at the injury site, possibly because of the inflammation and scarring present there. The injury site also typically has very limited blood supply and connective tissue, which might prevent donor cells from getting the nutrients they require.
Dr. Zhang's gel, however, can be loaded with different chemicals to stimulate various biological processes at the site of injury. In previous research done on rats, she was able to use the gel to help re-establish full blood supply at the site of brain injury. This could help create a better environment for donor cells.
In a follow-up study, Dr. Zhang loaded the gel with immature stem cells, as well as the chemicals they needed to develop into full-fledged adult brain cells. When rats with severe brain injuries were treated with this mixture for eight weeks, they showed signs of significant recovery. The new gel could treat patients at varying stages following injury, and is expected to be ready for testing in humans in about three years.
Strong Personalities Skew Study Samples
Birds of a feather flock together -- right into scientists' nets
By M. Farbman Posted 05.27.2009 at 10:08 am
All pet owners will happily explain to you their dog or cat's character traits -- probably in far more detail than you ever wanted to know. But the idea of animal personality is not one that's been formally studied all that much.
A new study has classed a species of bird into groups of more and less aggressive males. Researchers gauged the response of male collared flycatchers to female birds, to a strange object, and to other males. They found that each type of individual displayed consistent behavior in each of these situations.
However, they also found that the birds more likely to take risks also were the ones most likely to be trapped -- and thus studied further -- raising important questions about the skewed sample set presented when researchers base their findings on animals caught in traps. It's kind of like when talk show hosts say "95 percent of 13-year olds (who responded to our online survey) are smoking pot!!!" -- leaving out the part about it really being 95 percent ofthe particular 20 teenagers who felt like responding to our survey.