"Too simple" and "not so fast" suggest biological anthropologists from the George Washington University and New York University about the origins of human ancestry. In the upcoming issue of the journal Nature, the anthropologists question the claims that several prominent fossil discoveries made in the last decade are our human ancestors. Instead, the authors offer a more nuanced explanation of the fossils' place in the Tree of Life. They conclude that instead of being our ancestors the fossils more likely belong to extinct distant cousins.
Body
When doctors discover high concentrations of regulatory T cells in the tumors of breast cancer patients, the prognosis is often grim, though why exactly has long been unclear.
Now new research at the University of California, San Diego School of Medicine suggests these regulatory T cells, whose job is to help mediate the body's immune response, produce a protein that appears to hasten and intensify the spread of breast cancer to distant organs and, in doing so, dramatically increase the risk of death.
Northwestern University scientists have discovered a new mechanism in the core gears of the circadian clock. They found the loss of a certain gene, dubbed "twenty-four," messes up the rhythm of the common fruit fly's sleep-wake cycle, making it harder for the flies to awaken.
The circadian clock drives, among other things, when an organism wakes up and when it sleeps. While the Northwestern study was done using the fly Drosophila melanogaster, the findings have implications for humans.
The research will be published Feb. 17 in the journal Nature.
COLUMBIA, Mo. – Nobody enjoys colonoscopies, including mice. University of Missouri researchers are excited about the potential of using genetic biomarkers to predict colon cancer caused by inflammation. A new method developed at the MU Research Animal Diagnostic Laboratory (RADIL) could eventually lead to a method that might eliminate colonoscopies altogether.
Pneumococcus (Streptococcus pneumoniae) accounts for as much as 11 percent of mortality in young children worldwide. While successful vaccines like Prevnar® exist, they are expensive and only work against specific pneumococcal strains, with the risk of becoming less effective as new strains emerge.
INDIANAPOLIS – Researchers from Indiana University-Purdue University Indianapolis (U.S.A) and Umea° University (Sweden) report in a study published in the February 15, 2011, issue of PLoS Biology that a method by which cells repair breaks in their DNA, known as Break-induced Replication (BIR), is up to 2,800 times more likely to cause genetic mutation than normal cell repair.
Scientists are reporting for the first time that previously unrecognized substances released by algae blooms have the potential to act as endocrine disruptors, which can interfere with the normal activity of reproductive hormones. The effect is not caused by microcystin toxins, long recognized as potentially harmful to humans and aquatic animals, but as yet unidentified substances. As a result, the scientists are calling for a revision of environmental monitoring programs to watch for these new substances.
A long, urgent search for proteins in the blood of pregnant women that could be used in early diagnosis of ectopic pregnancy (EP) has resulted in discovery of biomarkers that seem to be specific enough to begin testing in clinical trials, scientists are reporting in a new study in ACS's Journal of Proteome Research.
Scientists in Hungary are reporting that the potential health effects of last October's Red Mud Disaster, one of the worst environmental accidents in Europe, may be less dangerous than previously feared. Their study, reported in ACS's journal Environmental Science & Technology, concludes that the dust from the mud may be no more harmful than particles of ordinary urban air pollution.
A Massachusetts General Hospital (MGH) study has identified a new role for an important enzyme in preparing lung tissue for the development of metastases. Published in the early edition of Proceedings of the National Academy of Sciences, the report describes how focal adhesion kinase (FAK) is involved in producing areas of vascular leakiness in lung tissue – known to be part of the premetastatic process – and increases expression of a molecule that attracts cancer cells to potential metastatic sites.
Scientists are reporting development and successful lab tests of "killer paper," a material intended for use as a new food packaging material that helps preserve foods by fighting the bacteria that cause spoilage. The paper, described in ACS's journal, Langmuir, contains a coating of silver nanoparticles, which are powerful anti-bacterial agents.
Frogs appear to be very sensitive to progestogens, a kind of pharmaceutical that is released into the environment. Female tadpoles that swim in water containing a specific progestogen, levonorgestrel, are subject to abnormal ovarian and oviduct development, resulting in adult sterility. This is shown by a new study conducted at Uppsala University and published today in the scientific journal Aquatic Toxicology.
Tomatoes spend so much time on shelves and in refrigerators that an estimated 20 percent are lost to spoilage, according to the U.S. Department of Agriculture (USDA). But scientists with USDA's Agricultural Research Service (ARS) are working with colleagues at Purdue University to extend the shelf life of tomatoes. The research also may lead to tomatoes that taste better and are more nutritious.
ARS is USDA's principal intramural scientific research agency, and the research results support the USDA priority of promoting international food security.
Smokers who continue to smoke while undergoing radiation treatments for head and neck cancer fare significantly worse than those who quit smoking before therapy, according to a study in the February issue of the International Journal of Radiation Oncology•Biology•Physics, an official journal of the American Society for Radiation Oncology (ASTRO).
Although the association between tobacco smoking and head and neck cancers has long been established, there had been little data until now showing whether continued smoking during treatment affects prognosis.