According to a report by the UN Scientific Committee on the Effects of Atomic Radiation in 2000, patients are exposed to about 200 times more ionizing radiation than medical workers. In some countries, this figure can be nearly 500 times.

In the quest to discover the root of illnesses, patients have to undergo an increasing number of scans and tests that may involve the use of ionising radiation to detect the source and scope of an ailment. However, this practice could also put patients at risk.

"There has been concern that new technologies are not providing the amount of patient protection that medical professionals had expected.

Massachusetts General Hospital (MGH) researchers have used gene therapy to restore useful vision to mice with degeneration of the light-sensing retinal rods and cones, a common cause of human blindness. Their report, appearing in the Oct. 14 Proceedings of the National Academy of Sciences, describes the effects of broadly expressing a light-sensitive protein in other neuronal cells found throughout the retina.

Two new articles examine the theory of "fetal programming" and their effect on racial health disparities. The studies, published in American Journal of Human Biology, suggest that the higher rates of hypertension and cardiovascular disease present in African Americans may be a consequence of low birth weights, and that these low birth weights may be a result of social rather than genetic factors.

The extra layer of information that you add to a message when speaking is called prosody. The most important conclusion is that prosody lies not only in the voice but also in the facial expression. Further it appears that auditory and visual information together are more effective than the same information separately. 

In middle age we begin to lose myelin, the fatty sheath of "insulation" that coats our nerve axons and allows for fast signaling bursts in our brains. So if you want to be the best at anything requiring speedy brain reaction times, you'd better get it in by age 39.

Writing in Neurobiology of Aging, Dr. George Bartzokis, professor of psychiatry at the UCLA Semel Institute for Neuroscience and Human Behavior at UCLA, and colleagues compared how quickly a group of males ranging in age from 23 to 80 could perform a motor task and then correlated their performances to their brains' myelin integrity.

The researchers found a striking correlation between the speed of the task and the integrity of myelination over the range of ages. Put another way, after middle age, we start to lose the battle to repair the myelin in our brain, and our motor and cognitive functions begin a long, slow downhill slide.

Engineers from the California Institute of Technology (Caltech) have created a "plug-and-play" synthetic RNA device--a sort of eminently customizable biological computer--that is capable of taking in and responding to more than one biological or environmental signal at a time.

In the future, such devices could have a multitude of potential medical applications, including being used as sensors to sniff out tumor cells or determine when to turn modified genes on or off during cancer therapy.

A synthetic RNA device is a biological device that uses engineered modular components made of RNA nucleotides to perform a specific function--for instance, to detect and respond to biochemical signals inside a cell or in its immediate environment.