Body

Leafcutter ant queens can live for twenty years, fertilizing millions of eggs with sperm stored after a single day of sexual activity.

Danish researchers who have studied ants at the Smithsonian Tropical Research Institute in Panama since 1992 discovered that in both ant and bee species in which queens have multiple mates, a male's seminal fluid favors the survival of its own sperm over the other males' sperm. However, once sperm has been stored, leafcutter ant queens neutralize male-male sperm competition with glandular secretions in their sperm-storage organ.

March 18, 2010 (Pasadena, Calif.) – Extreme obesity is affecting more children at younger ages, with 12 percent of black teenage girls, 11.2 percent of Hispanic teenage boys, 7.3 percent of boys and 5.5 percent of girls now classified as extremely obese, according to a Kaiser Permanente study of 710,949 children and teens that appears online in the Journal of Pediatrics.

Most kidney donors and recipients are in favor of exchanging personal health information that may influence success before scheduling a living organ donor transplant, while healthcare professionals are more reluctant, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society Nephrology (CJASN). The results suggest that clinicians should consider supporting and facilitating more information sharing before transplantation.

In physical, as in financial growth, it's not what you make but what you keep that counts, USC marine biologists believe.

Their study of genes associated with growth in oysters suggests that slow-growing animals waste energy in two ways: by making too much of some protein building blocks and then by having to dispose of the excess.

Donal Manahan, director of the USC Wrigley Institute for Environmental Studies and the study's senior author, calls the inefficient process "metabolic taxation."

Researchers in Australia have demonstrated that blocking a certain protein can reduce or prevent cigarette smoke-induced lung inflammation in mice. Inflammation underlies the disease process of chronic obstructive pulmonary disease (COPD) and many other smoking-related ailments.

The findings have been published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.

WASHINGTON, DC (March 18, 2010) – Although Asian Americans have long been portrayed as a "model minority" with few major problems, data released online today in the American Journal of Public Health (AJPH) reveal that distinct groups of Asian Americans, Native Hawaiians and Pacific Islanders (AA and NHPI) differ widely in death and disease rates, including from breast cancer and other conditions such as heart disease, and stand to benefit strongly from culturally appropriate care.

RECAN has developed a range of unique and highly specific monoclonal and polyclonal antibodies – the proteins produced in the blood which counteract bacteria, viruses or cancerous cells. This was achieved by first producing a number of recombinant proteins which are important components of cellular signalling pathways. These proteins themselves have direct uses in immunization and experimental studies.

Researchers are only beginning to understand how individual variation in gene regulation can have a lasting impact on one's health and susceptibility to certain diseases. Now, an ambitious survey of the human genome has identified differences in the binding of master regulators called transcription factors to DNA that affect how genes are expressed in different people.

Once the human genome was sequenced in 2001, the hunt was on for the genes that make each of us unique. But scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, and Yale and Stanford Universities in the USA, have found that we differ from each other mainly because of differences not in our genes, but in how they're regulated – turned on or off, for instance.

PHILADELPHIA, March 18, 2010 -- The number of U.S. medical students choosing internal medicine residencies inched higher from 2009 but not enough to significantly impact the shortage of primary care physicians.

LOS ANGELES – Physician scientists from the Cedars-Sinai Heart Institute presented new findings on the effectiveness of routine aspirin therapy for preventing heart disease, a drug therapy for atrial fibrillation and the role left ventricular assist devices (LVADs) may play in weight reduction for obese patients with chronic end-stage heart failure who are considered for heart transplantation. These presentations were made at the American College of Cardiology's Scientific Session in Atlanta. Brief highlights from these studies are included below.

ANN ARBOR, Mich. — Nurses participating in shift work, especially those working rotating shifts, face a significantly increased risk of developing Irritable Bowel Syndrome (IBS) and abdominal pain compared to those working a standard day-time schedule, according to research published in the American Journal of Gastroenterology.

STANFORD, Calif. — Recently, brain researchers have gained a powerful new way to troubleshoot neural circuits associated with depression, Parkinson's disease and other conditions in small animals such as rats. They use an optogenetics technology, invented at Stanford University, that precisely turns select brain cells on or off with flashes of light. Although useful, the optogenetics tool set has been limited.

Signals released by immune cells during a bout of inflammatory bowel disease interfere with intestinal cells' ability to regenerate. Yet people with inflammatory bowel diseases have a significantly higher risk of developing colon cancer: a hyper-activation of growth in those same intestinal cells.

Scientists report a protein made by a gene already associated with a handful of human inflammatory immune diseases plays a pivotal role in protecting the intestinal tract from colitis.

St. Jude Children's Research Hospital investigators led the research, which points to possible new strategies for combating colitis. Colitis is a chronic inflammatory disease associated with colon damage, resulting in abdominal pain, bleeding and other symptoms.