Latest University of Pennsylvania School Stories

(Philadelphia, PA) - A study by researchers at the Transdisciplinary Tobacco Use Research Center (TTURC) of the University of Pennsylvania School of Medicine indicates that a smoker's genetic make-up may affect whether they quit or not while using either bupropion (Zyban) or nicotine replacement therapies (NRTs) such as the nicotine patch or nasal spray. The results appear in the August issue of Neuropsychopharmacology. "This study provides new evidence that genetic differences in the...

(Philadelphia, PA) "“ Researchers at the University of Pennsylvania School of Medicine have discovered that the recently identified neurotransmitter orexin (also known as hypocretin) influences reward processing by activating neurons in the lateral hypothalamus region of the brain. By identifying the relationship between orexin neurons and behaviors associated with reward seeking, drug relapse, and addiction, researchers hope to find new treatments for drug addiction. Previous studies have...

Researchers at the University of Pennsylvania School of Medicine have published the first study to test the role of RNA chemical modifications on immunity. They have demonstrated that RNA from bacteria stimulates immune cells to orchestrate destruction of invading pathogens. Most RNA from human cells is recognized as being self and does not stimulate an immune response to the same extent as invading bacteria or viruses. The researchers hypothesize that if this self-recognition fails, then...

(Philadelphia, PA) - It is well known that aspirin, a non-selective, non-steroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX), reduces the risk of heart attack and stroke. Non-aspirin non-steroidal anti-inflammatory drugs (NANSAIDs) such as ibuprofen and naproxen may reduce this same risk, but studies have shown conflicting results. Some have shown no association between NANSAIDs and heart attacks; some have shown an increased risk; and others have suggested a lower...

Philadelphia, PA -- Otters cavorting in the water is a scene with which we're all familiar. Yet, unlike many other mammals that spend a considerable amount of time in the water"“polar bears, seals, dolphins, and whales"“river otters do not have a thick layer of body fat to keep warm. They rely, instead, on a few unique adaptations; namely, their fur and the densely packed layer of specially adapted underhairs. Using scanning electron microscopy and polarizing light microsopy, John W....

In a commentary piece in the August 10th issue of the Journal of the American Medical Association, Scott D. Halpern, MD, PhD, of the University of Pennsylvania School of Medicine, calls for a revision of existing state laws so that HIV-testing may be carried out when patients are not able to give their direct consent for such testing. The paper is entitled, "HIV Testing without Consent in Critically Ill Patients." At present, except for tests for heritable genetic disorders, HIV is...

(Philadelphia, PA) - Researchers from the University of Pennsylvania School of Medicine found that a protein called NF-Ya activates several genes known to regulate the development of hematopoietic stem cells (HSC), or blood-producing stem cells, in bone marrow. Knowing the details of this pathway may one day lead to new treatments for such blood diseases as leukemia, as well as a better understanding of how HSCs work in the context of bone-marrow and peripheral-stem-cell transplantation. The...

(Philadelphia, PA) - Researchers from the University of Pennsylvania School of Medicine have found that inhibitors of an enzyme called cathepsin L prevent the SARS (severe acute respiratory syndrome) virus from entering target cells. SARS is caused by an emergent coronavirus. There is no effective treatment at this time. This study also demonstrates a new mechanism for how viral proteins are activated within host cells, states senior author Paul Bates, PhD, an Associate Professor in the...

(Philadelphia, PA) - Researchers at the University of Pennsylvania School of Medicine have determined how serotonin decreases the body's sensitivity to light and that exposure to constant darkness leads to a decrease in serotonin levels in the brain of fruit flies. These findings suggest that serotonin may play a role in maintaining circadian rhythm, as well as modulating light-related disorders such as seasonal affective disorder (SAD). Senior author Amita Sehgal, PhD, Professor of...

(Philadelphia, PA) - For the first time ever, using "laser tweezers," the mechanical properties of an individual fiber in a blood clot have been determined by researchers at the University of Pennsylvania School of Medicine. Their work, led by John W. Weisel, PhD, Professor of Cell and Developmental Biology at Penn, and published in this week\'s early online edition of the Proceedings of the National Academy of Sciences, provides a basis for understanding how the elasticity of the whole clot...