Researchers confirmed that a daily, combined dose of estrogen and progestin increases breast cancer risk in post menopausal women, but added that this risk begins to return to normal about six months after women stop taking the hormones. “It is reassuring that breast cancer risk begins to return to normal six months after women stop combined dose estrogen-progestin therapy,” said Duane Alexander, M.D., Director of the NICHD. “Women, in consultation with their physicians, need to make the most informed decision possible. The study authors have provided them with one more piece of important information.”
The prospect of using bacteria to manufacture complex human proteins for use in therapeutic drugs is a step closer thanks to new research published today in Science. Researchers from Switzerland and the UK report they have engineered the bacterium Escherichia coli to carry a vital piece of cell machinery that adds sugar molecules to newly synthesized proteins by a process known as glycosylation. The finding opens up the possibility of producing complex human proteins such as Factor VIII and the hormone erythropoietin, which stimulates the production of red blood cells by stem cells in bone marrow. Both these proteins, which require the addition of sugar molecules to function properly, are currently produced by culturing mammalian cells, which can be a costly and technically difficult process.
Treating the underlying cause of asthma rather than its symptoms appears to be more effective at reducing severe asthma attacks, according to new research reported in The Lancet. Asthma is known to be associated with increased numbers of microscopic cells called eosinophils, in the airway. These can be detected by a simple sputum test and their numbers rise several weeks before an asthma attack. A study of 74 patients with moderate to severe asthma were randomly placed into two groups. One was treated conventionally, the other using the sputum test with their medication regulated in response to changes in eosinophil numbers. The results showed that the sputum test group had fewer severe attacks and hospitalisations than the conventional treatment group.
An accepted assumption in astrophysics holds that it takes more than 1 million years for gas giant planets such as Jupiter and Saturn to form from the cosmic debris circling a young star. But new research suggests such planets form in a dramatically shorter period, as little as a few hundred years. The forming planets have to be able to survive the effects of nearby stars burning brightly, heating and dispersing the gases that accumulate around the giant planets. If the process takes too long, the gases will be dissipated by the radiation from those stars, said University of Washington astrophysicist Thomas R. Quinn.
The energy required to create an accurate quantum computer may limit the ability of scientists to make these novel devices small, fast, cheap and efficient, says a University of Arkansas researcher. Quantum computing relies on using single atomic particles as units for information storage. Manipulating this information requires pulsed electromagnetic fields?which contain energy. The researcher found that the energy needed to perform a calculation is inversely proportional to the error rate: In other words, more energy means less uncertainty.
Nearly 40 years ago scientists were startled to discover that the eye, far from being a still camera, actually has cells that respond to movement. Moreover, these cells are specialized to respond to movement in one direction only, such as left to right or right to left. Now, in a paper in this week’s issue of the journal Nature, biologists at the University of California, Berkeley, have finally detailed the cellular circuit responsible for motion detection in the eye’s retina.