Reuters - Nearly 8,000 older Americans who fell and banged their heads died from the brain injury in 2005, according to a government study released on Monday.

AP - Researchers have uncovered a new clue to the cause of Alzheimer's disease.

AP - Pick a tomato in the blazing sun and plunge it straight into cold water. If that happened on the way to market, it might be contaminated.

AP - Researchers have uncovered a new clue to the cause of Alzheimer's disease. The brains of people with the memory-robbing form of dementia are cluttered with a plaque made up of beta-amyloid, a sticky protein. But there long has been a question whether this is a cause of the disease or a side effect. Also involved are tangles of a protein called tau; some scientists suspect this is the cause.

AP - The government acknowledged that an outbreak of one of the most contagious animal diseases from any of five locations being considered for a new high-security laboratory — an event it considered highly unlikely — would be more devastating to the U.S. economy than an outbreak from the isolated island lab where such research is now conducted.

Reuters - Falling levels of a hormone called leptin that helps the brain resist tempting foods may explain why people who lose weight often have a hard time keeping it off, U.S. researchers said on Friday.