In the animal world, it’s common for females to mate with several males during one and the same reproductive period. This leads to sperm competition, that is, sperm from several different males compete to fertilize the egg at the same time.

The most common response to increased sperm competition is for males to increase the number of sperm cells to inseminate a female with. Since males’ sperm reserves are not unlimited, males should be economical in using their sperm resources. Therefore, a

New data presented by Emory researchers at the American Heart Association’s Scientific Sessions abstract poster sessions today address angina related quality of life in diabetic and non-diabetic patients undergoing percutaneous coronary intervention (PCI), medical procedures performed in catheterization laboratories to reduce the amount of narrowing in a coronary artery due to plaque formation.

According to Emory Heart Center cardiologist William Weintraub, M.D. FACC, who headed the re

Say researchers from Wake Forest University Baptist Medical Center

If you’re helpless without your glasses, try using your ears.

For some tasks, hearing can augment poor eyesight, according to research reported by Wake Forest University Baptist Medical Center today at the annual meeting of the Society for Neuroscience in New Orleans.

“It has been long known that blind people often develop more acute hearing,” said Mark Wallace, Ph.D., senior researcher. “What w

American Heart Association meeting report

About one in eight schoolchildren have three or more risk factors of the metabolic syndrome, a precursor of cardiovascular disease, researchers reported today at the American Heart Association’s Scientific Sessions 2003.

“The risk was about 1.6 times higher for girls than boys,” said the study’s lead author Joanne S. Harrell, Ph.D., professor of nursing and director of the Center for Research on Chronic Illness at the Univer

Researchers led by Jason Jaworski, PhD, and Michael Kuhar, PhD, both at the Yerkes National Primate Research Center at Emory University, have shown that CART peptide, a chemical that occurs naturally in both the rodent and human brain, reduces some effects of cocaine when additional amounts are administered to the region of the brain that is associated with reward and addiction. These findings, which appear online in the Journal of Pharmacology and Experimental Therapeutics and which will be presente

At the annual meeting of the Americal Society for Human Genetics in Los Angeles, Hopkins researchers will reveal the existence of specific short repeats of particular genetic building blocks in the gene at the root of cystic fibrosis, an inherited and often fatal lung disease. The researchers will also show how the repetitious pattern may help predict the disease’s severity.

Cystic fibrosis, or CF, stems from mutations in a gene called CFTR, short for cystic fibrosis transmembrane cond

For years, the origin of Kaposi’s sarcoma (KS), a rare cancer that sometimes afflicts those infected with HIV, the AIDS virus, has puzzled researchers. Now, pathologists at Jefferson Medical College may be uncovering some of its secrets.

George Murphy, M.D., professor of pathology at Jefferson Medical College of Thomas Jefferson University in Philadelphia, and Masatoshi Deguchi, M.D., visiting scientist from Tohuku University in Sendai, Japan, have created a mouse model that resembles an ea

Now patients with rheumatoid arthritis (RA) can be diagnosed considerably earlier, thereby increasing their chances of being treated successfully. This is a consequence of new findings by Professor Solbritt Rantapää-Dahlqvist’s research team at the Unit for Rheumology, Department of Public Health and Clinical Medicine, Umeå University in Sweden.

Rheumatoid arthritis, also known as arthritic rheumatism, is a severe disease where the body’s immune defense system attacks the body’s own joint ca

A research team at Lund University in Sweden attracted international attention a year ago by showing that new nerve cells can be generated in the brain after a stroke. However, most of these new nerve cells die rather soon. The same research team has now been able to show that an inflammation can lie behind the death of these new nerve cells, which instills hope for improved treatments for various brain disorders.

The new growth of nerve cells following epilepsy or stroke has been shown in a

Despite the rich knowledge scientists now have of the genes that constitute the human genome, researchers have yet to unravel the precise choreography by which they work – or malfunction – together in the cell in response to triggers from the outside world.

“There is a code we need to understand to determine what happens to a cell under many different conditions, and ultimately to make predictions of how an entire genome is regulated,” explains Julia Zeitlinger, a postdoctoral associate at

While the medical community has been exploring the use of bacteriophages, a form of virus that can be used to manage bacteria that have become resistant to antibiotics, plant pathologists with the American Phytopathological Society (APS) now say that this same approach may also help fight plant disease.

According to Jason Gill, a phage researcher at the University of Guelph, Guelph, Ontario, phages have been proposed as plant-pathogen control agents in a process known as phage therapy–the

A new study cautions that drugs being designed to enhance some forms of memory in the elderly may actually worsen working memory, such as the cognitive ability to hold a phone number in mind long enough to dial it.

The research, published online in Neuron on November 5, analyzes the effects of these drugs on multiple brain regions and suggests that the medications may actually have hazardous consequences on higher-order thought processes that are regulated by the prefrontal cortex.

People with depression are five times more likely to have a breathing-related sleep disorder than non-depressed people, according to a study at the Stanford University School of Medicine. The study is the first to show a link between depression and sleep apnea along with its related disorders.

Although it remains unclear how the conditions are linked, Maurice Ohayon, MD, PhD, said his study should encourage physicians to test depressed patients for this type of sleep disorder.

“Ph

Detection of toxic ’atheronal’ molecules may lead to new diagnostics

A team of investigators led by The Scripps Research Institute (TSRI) President Richard A. Lerner, M.D., and TSRI Associate Professor Paul Wentworth, Jr., Ph.D., are reporting evidence for the production of ozone in fatty atherosclerotic plaques taken from diseased arteries.

Lerner is Lita Annenberg Hazen Professor of Immunochemistry and holds the Cecil H. and Ida M. Green Chair in Chemistry at TSRI. He is a

Researchers at Brown University and the Marine Biological Laboratory at Woods Hole, Mass., have found a physical connection between the herpes simplex virus and amyloid precursor protein, a protein that breaks down to form a major component of the amyloid plaques that are consistently present in the brains of persons with Alzheimer’s disease.

Amyloid precursor protein – or APP – breaks down to form beta-amyloid. There is strong evidence, according to the researchers, that beta-amyloid

An innovative vaccine against tuberculosis has shown promise in persons with HIV, researchers from Dartmouth Medical School and the National Public Health Institute of Finland report in the Nov. 7 issue of the journal AIDS.
An international team led by DMS infectious disease expert Dr. C. Fordham von Reyn, professor of medicine, found that the new booster, a killed vaccine, enhanced the TB immunity of HIV patients. Their weakened immune systems make the current TB vaccine, which is a live vacci