Biology

Scientists have identified a molecular cause behind the ravages of old age and in doing so have also shown how a natural process for fighting cancer in younger persons can actually promote cancer in older individuals.

Natural changes in voltage that occur across the membrane of adult human stem cells are a powerful controlling factor in the process by which these stem cells differentiate, according to research published by Tufts University scientists.

A UCLA study shows for the first time how microscopic crystals form sound and gravity sensors inside the inner ear. Located at the ends of cilia — tiny cellular hairs in the ear that move and transmit signals — these crystals play an important role in detecting sound, maintaining balance and regulating movement.

Scientists from the California Institute of Technology (Caltech) have created images of the heart's muscular layer that show, for the first time, the connection between the configuration of those muscles and the way the human heart contracts.

Cells shut down and stop dividing when their DNA is damaged, providing protection against cancer. However, a new study has found these cells also spew proteins into the cells’ surrounding environment. The process, called cellular senescence, causes inflammation and sets up conditions that support the development of age-related diseases including, ironically, cancer.

One of the defining characteristics of cancer cells is that they systematically prevent programmed cell death (apoptosis), with which the body guards itself against the proliferation of defective cells. In order to do this, they express so-called apoptosis inhibitors (IAPs) among other proteins.

2008 was a great summer for sports' fans. World records tumbled at the Beijing Olympics. Usain Bolt shattered both the 100m and 200m world records, knocking tenths of a second off each. People have been getting faster and faster over the last few decades, which made marathon runner Mark Denny, from Stanford University, wonder whether last century's massive increase in population could account for these dramatic improvements. He also wondered whether there are absolute limits on running speeds and, if so, how close are we to them?

Researchers have discovered that DNA damage decreases a cell's ability to regulate which genes are turned on and off in particular settings. This mechanism, which applies both to fungus and to us, might represent a universal culprit for aging.

Researchers at the University of Washington (UW) have reported for the first time that mammals can be stimulated to regrow inner nerve cells in their damaged retinas. Located in the back of the eye, the retina's role in vision is to convert light into nerve impulses to the brain.

A virus that causes cold-like symptoms in humans originated in birds and may have crossed the species barrier around 200 years ago, according to an article published in the December issue of the Journal of General Virology. Scientists hope their findings will help us understand how potentially deadly viruses emerge in humans.

Imagine yourself swimming in a pool: It's the movement of your arms and legs, not the viscosity of the water, that mostly dictates the speed and direction that you swim. For tiny organisms, the situation is different. Microbes' speed and direction are subjected more to the physical vagaries of the fluid around them.

The first tissue-engineered trachea (windpipe), utilising the patient's own stem cells, has been successfully transplanted into a young woman with a failing airway. The bioengineered trachea immediately provided the patient with a normally functioning airway, thereby saving her life. These remarkable results provide crucial new evidence that adult stem cells, combined with biologically compatible materials, can offer genuine solutions to other serious illnesses.

Scientists have long known that life can exist in some very extreme environments. But Earth continues to surprise us. At a European Science Foundation and COST (European Cooperation in the field of Scientific and Technical Research) 'Frontiers of Science' meeting in Sicily in October, scientists described apparently productive ecosystems in two places where life was not known before, under the Antarctic ice sheet, and above concentrated salt lakes beneath the Mediterranean. In both cases, innumerable tiny microbes are fixing or holding onto quantities of organic carbon large enough to be significant in the global carbon cycle.

Under normal circumstances, the cells of the immune system (T cells, B cells, and other lymphocytes) cooperate to police our bodies for evidence of disease, mounting highly coordinated attacks against foreign invaders and cancerous cells. However, the immune system can occasionally become deranged, directing its arsenal against friend not foe, to attack healthy body tissues—a condition called autoimmunity. Fortunately, autoimmunity is rare, because the regulatory arm of the immune system works to suppress inappropriate inflammatory flare-ups before they evolve into full-blown conflagrations.

It has all the hallmarks of a Cretaceous melodrama. A dinosaur sits on her nest of a dozen eggs on a sandy river beach. Water levels rise, and the mother is faced with a dilemma: Stay or abandon her unhatched offspring to the flood and scramble to safety?