University Times

Grants awarded to researchers

Thomas Kamarck of the psychology department has received a $333,424 grant from the National Heart, Lung and Blood Institute as principal investigator of a study of "Biobehavioral Factors in Atherosclerotic Progression."

The National Institute of Dental Research has awarded Mary Marazita of the Cleft Palate Center a $369,963 grant for a gene mapping study of cleft lip, with or without cleft palate, in the populations of Shanghai, China and West Bengal, India.

Peter Strick of neurobiology has been awarded a $610,976 grant from the National Institute of Neurological Disorders and Stroke to study premotor areas of the brain's frontal lobe.

The National Cancer Institute has granted $600,973 to Richard Swensson of radiology to study "Detection and Localization in Mammography."

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Super strong polymers are possible

Adding solid rods measuring just a few billionths of a meter long to polymers can dramatically improve the mechanical, thermal and electrical properties of the mixture, according to a study by Pitt researchers.

The researchers, led by Anna C. Balazs of the chemical and petroleum engineering department, and David Jasnow, chairperson of physics and astronomy, used two-dimensional simulations to examine how the tiny rods interacted in mixtures of two polymers.

Their findings, published this summer in the journal Science, could lead to faster and easier production of electrically conducting pathways in insulating materials or to the creation of reinforcing structures in organic/inorganic composites.

Researchers found that nanotubes embedded in the polymers that naturally repel one another can align end-to-end, creating possible electrical pathways in the mixture. Rodlike nanoparticles naturally arrange themselves into percolating networks that strengthen the polymer blend to which they are added.

"Manufacturers are already aware that adding larger particles to polymers can increase the strength. Anyone with a reinforced tennis racquet or automobile tires is already taking advantage of this phenomenon. We're showing that it's possible on the nano-scale, as well," Balacz said.

The findings could help lead to more efficient car batteries and lightweight parts for automobile bodies and chassis, researchers said.

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Minimally invasive esophagectomy may lower death rate

Minimally invasive surgery for esophagectomy (removal of the esophagus) may reduce the death rate associated with open esophagectomy, according to a study by UPMC Health System surgeons.

The study was conducted from August 1996 to September 1999 and involved 77 patients (average age: 66) who underwent minimally invasive procedures for esophagectomy. The patients' average hospital stay was seven days. None died.

"The results of this study show that minimally invasive esophagectomy is technically feasible and safe in a center where surgeons have extensive experience in both minimally invasive and open esophagectomy," said James Luketich, principal investigator of the study, Pitt assistant professor of surgery and section head of thoracic surgery.

Study results were published in the September issue of Annals of Thoracic Surgery.

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Team develops nerve agent detoxifier

A disposable washcloth and foam are the newest weapons in the fight against chemical warfare, using technology developed at Pitt.

Alan J. Russell, chairperson of the chemical and petroleum engineering department, and former graduate student Keith E. LeJeune, have developed a way to use enzymes to neutralize and identify nerve agents.

Their invention — Agentase EnzymeFoamD2-1 — was commercialized by Agentase, LLC, where LeJeune is now chief executive officer. R&D Magazine honored Agentase Enzyme-FoamD2-1 as one of the top 100 innovations of the year. It was tested Sept. 9 at Pittsburgh's domestic preparedness chemical weapons field exercise.

Russell said the invention is faster, more effective and more convenient than other current and proposed methods of nerve gas detoxification.

Those other methods include incineration, hypochloride bleaching and supercritical water (which requires submerging contaminated equipment in water in extreme pressure and high temperatures).

Each method frequently destroys the contaminated equipment. Each also destroys the "fingerprint" of the nerve agent involved, making it impossible to do post-incident forensics.

Convenience is another advantage of the foam and washcloth method. The other methods have onerous requirements such as holding containers and large amounts of bleach and water.

Also, EnzymeFoamD2-1 can be used to decontaminate soldiers and emergency workers themselves, something that cannot be done with bleaching, incineration or supercritical water.

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Low-dose oral contraceptives as protective against ovarian cancer as high-dose pills

Low-dose contraceptives already on the market are just as effective as older, high-dose preparations in protecting women from ovarian cancer, according to researchers at Pitt's Graduate School of Public Health (GSPH).

"Our study shows that women who are taking, or have taken, low-dose oral contraceptives have a 40 percent reduction in risk of ovarian cancer — the same risk reduction provided by the older, high-dose birth control pills," said senior author Roberta Ness, associate professor of epidemiology at GSPH.

In addition, researchers found that this protection begins soon after initiating use, and continues for at least 30 years after stopping use.

Previous research has shown that women taking pre-1980 oral contraceptives were less likely to develop ovarian cancer than were women who had never used them. But in the last two decades, the amounts of estrogen and progestin in oral contraceptives have steadily decreased, and new progestins have been introduced. Pitt's study is the first population-based, case-controlled effort to examine risk protection offered by the newer preparations.

Study results were published in the Aug. 1 issue of the American Journal of Epidemiology.

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Antiretroviral drugs not foolproof against sexual transmission of HIV

Antiretroviral therapy for HIV patients can be a double-edged sword, according to researchers.

Investigators showed that while the drugs can greatly reduce the amount of infectious HIV in semen, a substantial percentage of men may still be able to transmit the virus sexually. This is the first study to simulate a clinical environment in looking at the effects of antiretroviral drugs on HIV concentration in semen. The findings, made by researchers at the Graduate School of Public Health and School of Medicine, and Brazil's Universidade Federal do Rio de Janeiro, were published in the Annals of Internal Medicine.

"Our study is the first to show that, in a real-world setting, a substantial percentage of HIV-positive men have active, potentially infectious virus in their semen, even after six months of therapy," said Lee Harrison, Pitt associate professor of medicine and epidemiology, director of the University's Public Health Infectious Diseases Lab and senior author of the study.

Previous small, short-term studies have suggested that antiretroviral therapy reduces, but does not eliminate, the amount of infectious HIV in semen. But, because the earlier studies were not definitive, scientists remained unsure whether the findings would translate into a larger community setting.

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