Heart Implants???
Heart failure treatment might be getting a facelift. Researchers around the world are currently attempting to establish whether dead or damaged heart muscle cells can be replaced by either skeletal muscle cells or bone marrow cells. Several studies have been succesful on a limited scale in showing that heart function improves when patients are given injections of skeletal muscle cells into the damaged areas of their hearts. So far, it seems as though the new cells implant themselves into the scarred areas, and are able to become an active part of the heart. This might allow the heart to pump with increased force. It also seems that bone marrow cell implants have similar effects, but work best when combined with heart bypass surgery. However, drug regimes are necessary for patients undergoing these treatments. Until the new cells make themselves at home, the patients are at risk of developing arrhythmias, which could lead to further heart deterioration if not properly controlled. Heart disease is still the leading cause of death in the US. As such, it is imperative that treatments such as these be developed in order to reduce the current need for transplants and bypass operations.
Seal Smarts
If you have ever been to a wildlife entertainment park, you have probably seen seals in action. Their antics and trainability have made them popular attractions. In the wild however, they live a completely different life. The intelligence that we only glimpse while watching a choreographed show is what helps them survive. In the Pacific Northwest, the Killer whale is the main predator that seals have to watch out for. Many Killer whales travel in family pods that feed mainly on fish. However, there are other Killer whales that travel in smaller groups, and hunt only seals. Volker Deecke, a Killer whale biologist at the Vancouver Aquarium Marine Science Center, has studied the dialects of these groups of whales and found them to be quite distinct. Recently, Deecke played these differing whale songs to groups of seals and observed their behavior. He found that the seals basically ignored the songs of the fish-eating whales, but quickly fled at the sound of the dangerous seal-eaters. This research suggests that the seals have learned who they can trust (and who they can't), and recognize those individuals in their environment by the sound of their voice.
Don't Drink if you are Pregnant!
A recent rodent study gave pregnant rats the equivalent amount of alcohol to one drink a day for a human during the initial two trimesters of pregnancy. After the pups were born and reared to adulthood, they were tested on a navigational task, which they failed. Hormone levels of the rats were tested, and it was found that glutamate levels were low, especially in the hippocampus. Glutamate is important for sending neuronal messages from neuron to neuron. The hippocampus is essential to learning and memory, and if damaged during development will lead to impairment in numerous cognitive tasks throughout adulthood. Researchers at the University of New Mexico who developed the experiment believe that although it is difficult to compare effects taking place in rodents to what might happen humans, it is still important to keep in mind that the effects of alcohol consumption during pregnancy may contribute to subtle cognitive deficits.
current science news posted by Kirsten at 11/22/2002 04:10:00 PM
Scientists
& Engineers for America
RSS
