Skeletal muscles naturally repair themselves very efficiently after injury. But when they don't, otherwise successful recovery following damage from overuse during exercise, surgery or trauma can be stymied. Furthermore, as we age, muscle repair slows noticeably, and in Duchenne Muscular Dystrophy and other degenerative muscle diseases, normal repair functions can't cope with disease progression.

Aspergillus fumigatus is a medically important fungus, causing potentially life-threatening infections in patients with weakened immune systems. It is also a major cause of respiratory allergy, and it is implicated in asthma as well. The fungus has always been thought to lack the ability to reproduce sexually, but new discoveries by a multinational group of scientists indicate that the fungus has a number of characteristics of sex. The possible presence of sex in the species is highly significant because it may affect the way researchers study--and try to control--disease associated with the fungus.

Billions of people tuned into recent Live 8 concert broadcasts, some just for the music, others to support the altruistic cause spearheaded by former Boomtown Rat, Sir Bob Geldof. In today's rat-race climate, what makes some of us look out for each other, while others look out for themselves?

Over the years, a number of Weizmann Institute scientists have addressed the question of how molecules essential to life, such as proteins, have adapted to function in extreme environments. The proteins they investigated were isolated from halophilic (salt-loving) microorganisms from the Dead Sea. After determining the 3-D structures for several halophilic proteins, researchers were able to explain how these proteins not only cope with high salinities, but are actually "addicted" to them. However, the alga Dunaliella salina is an organism of a different streak: it is able to grow in any salinity, from the extremes of the Dead Sea to nearly fresh water. The uniquely salt-tolerant Dunaliella, which is commercially grown as a source of natural beta carotene, has been investigated at the Weizmann Institute for over 30 years. Yet, the secrets of its exceptionally successful adaptation to salt remained unresolved.

Duke University Medical Center researchers have identified a new protein that plays a critical role in enabling the heart to respond to such external stimuli as exercise or stress, as well as in the progressive loss of heart function that is heart failure, the researchers said.

A new study in the July 18 issue of The Journal of Experimental Medicine shows that gold-colored bacteria are more harmful than their unpigmented relatives. A group of scientists led by Victor Nizet (UCSD, San Diego, CA) have discovered that the molecules that give certain bugs their color also help them resist attack by immune cells called neutrophils.

Boosting levels of two critical proteins that normally shut down during Huntington's disease, researchers at the University of Wisconsin-Madison and the Cold Spring Harbor Laboratory have cured fruit flies of the genetic, neurodegenerative condition.

A molecule that helps the body's motor nerve cells grow along proper paths during embryonic development also plays a major role in inhibiting spinal-cord neurons from regenerating after injury, researchers at UT Southwestern Medical Center have found. In cultured cells, the researchers found that a component of myelin – a substance that normally insulates and stabilizes long nerve fibers in adult vertebrates – chemically blocks the ability of nerve cells to grow through myelin that is released when the spinal cord is damaged. While other myelin components also block nerve growth, a component called ephrin-B3 inhibits such activity as well or better than that of other known blocking agents combined, UT Southwestern researchers report in an upcoming issue of the Proceedings of the National Academy of Sciences.

Scientists interested in ancient life have a wealth of fossils and impressions frozen in rocks that they can study from as far back as 540 million years ago – when animals with shells and bones began to become plentiful. But evidence of complex life older than 540 million years is scant and difficult to study.