Researchers in Japan have developed a pair of molecular-scale scissors that open and close in response to light. The tiny scissors are the first example of a molecular machine capable of mechanically manipulating molecules by using light, the scientists say.

The scissors measure just three nanometers in length, small enough to deliver drugs into cells or manipulate genes and other biological molecules, says principal investigator Takuzo Aida, Ph.D., professor of chemistry and biotechnology at the University of Tokyo.

The medication tilarginine, a drug that was believed could be beneficial for patients who develop cardiogenic shock (low blood pressure due to impaired cardiac function) after a heart attack, did not reduce the risk of death up to six months after a heart attack, according to a JAMA study published online March 26. The study is being released early to coincide with its presentation at the American College of Cardiology's annual conference.

High concentrations of nitrogen dioxide gas — inhaled for even very brief periods following fires, explosions of military munitions or detonations of terrorist devices — could cause serious lung damage, scientists reported today at the 233rd national meeting of the American Chemical Society.

Dr. Zengfa Gu, M.D., Ph.D., and colleagues at the Walter Reed Army Institute of Research, Silver Spring, Md., reached that conclusion based on experiments with laboratory rats that were exposed to the toxic gas. Gu explained that previous research showed that chronic exposure to low and moderate levels of nitrogen dioxide could damage the lungs. However, there was no clear information on the health risks of brief, high-level exposures lasting only a few minutes.

Researchers at the U.S. Department of Energy’s Ames Laboratory are employing some modern day alchemy in an effort to find a material with properties of rare and high-priced palladium. If they’re successful, it could remove a major roadblock from the path of hydrogen fuel-cell powered vehicles.

Hydrogen fuel-cell technology sounds almost too good to be true. You combine cheap and plentiful hydrogen and oxygen gas, the fuel cell generates electricity and the by-product is simply water. But it’s a little more involved.

The size, type, and dispersion of nanomaterials could all play a role in how these materials impact human health and the environment, according to two groups of researchers at Rensselaer Polytechnic Institute. In new studies, the teams found that while carbon nanotubes inhibited growth in mammalian cells, they sustained the growth of commonly occurring bacteria.

The seemingly contradictory findings highlight the need for society to better grasp the impacts these infinitesimally small particles could have when released into the environment or the human body, the researchers said.

In one of the most comprehensive and definitive studies of its kind to date, a team of researchers at the University of California, Davis have proven that organically grown kiwifruit contain more health-promoting factors than those grown under conventional conditions. The research is reported in the SCI’s magazine Chemistry & Industry. The debate over the relative health benefits of organic versus conventional food has raged for years, with UK environment secretary David Miliband declaring in January that buying organic is just a lifestyle choice.