University Times

Short exercise sessions are effective treatment for obesity

Several short sessions with home training equipment may be the most effective exercise program for obese patients, according to a Pitt study.

"This study not only validated the use of short exercise sessions in treating obese patients, but it was the first clinical study that we know of to actually incorporate and test the effectiveness of home exercise equipment on weight control programs," said principal investigator John M. Jakicic, research assistant professor at Pitt's medical school.

In the study, 139 sedentary, clinically obese women (20-75 percent above ideal body weight) were placed in one of three 20-week behavioral weight control programs designed by Pitt researchers. All participants were instructed to reduce their fat and caloric intake and were randomly assigned to one of three exercise regimens.

Each group was instructed to exercise five days a week, gradually increasing the duration from 20 to 40 minutes daily. One group exercised in a single, continuous session, while the two other groups divided their exercise into several 10 minute bouts. Home exercise equipment was available to one of the latter groups.

"Both in terms of exercise adherence and total weight loss, we found that the group using exercise equipment for short periods of time was the most successful," Jakicic reported.

"The most effective exercise regimen is one that a patient will actually do, and it appears that these convenient, shorter sessions with the equipment promote maintaining higher levels of exercise participation," he said.

An estimated 56 million Americans are at least 20 percent above their ideal body weight, which leaves them at increased risk for heart disease, diabetes, stroke and other conditions. Few overweight people exercise regularly, often citing lack of time as the major reason, researchers say.

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Liver cell infusion can help correct rare metabolic liver disease, research shows

Researchers from UPMC Health System and two other medical centers have combined forces to show that an infusion of liver cells can function for more than a year to partially correct a rare liver disease.

The procedure, reported in the May 14 New England Journal of Medicine, suggests that cell transplantation may have broader applications and be a safer and less invasive treatment than liver transplantation for some patients.

The liver cell infusion took place in April 1997 at the University of Nebraska Medical Center in Omaha. It was performed on a 10-year-old girl suffering from Crigler-Najjar Syndrome Type I, a rare disease in which the liver does not make the enzyme that allows bilirubin, a blood cell byproduct, to be normally excreted by the body.

Patients with Crigler-Najjar disease develop jaundice and must spend 12 hours a day or longer receiving phototherapy, which helps degrade bilirubin in the skin so it can be cleared from the body. Other than a liver transplant, there is no cure for the disease. The oldest living person with Crigler-Najjar is 31 and few patients live beyond their teens.

Because liver transplantation is risky, surgeons decided to try the less invasive cell transplant procedure. Approximately 7 billion cells, comprising 5 percent of the liver's mass, were infused through a catheter into a blood vessel leading into the patient's liver.

The cells came from a donor liver that wasn't suitable for whole organ transplantation, although the liver cells were fine. Pitt pathology professor Stephen Strom and his team at UPMC Health System isolated the cells, which were transported by air carrier to Nebraska.

Since the procedure, the patient's daily light therapy has been reduced from 10-12 hours to 6-7 hours, and she has become significantly less jaundiced, the researchers report. Because the donor liver cells are foreign to the patient's body, she must take immunosuppression drugs. The authors report no signs of rejection.

"Now that we know long-term cell functioning is possible, the infusion of additional liver cells may completely free the patient from the need for phototherapy," Strom said. "Ultimately, it could mean that this disease, and other diseases of the liver, may be cured without the need for whole-organ transplantation."

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Pitt cancer institute researcher gets grant

Andrew Baum, deputy director for cancer control and prevention at the University of Pittsburgh Cancer Institute (UPCI), has received a $103,000 grant from the National Cancer Institute's Office of Cancer Survivorship for his research on prostate cancer survivors' quality of life.

Prostate cancer is the most common form of cancer among men in the United States, accounting for 209,000 new cases in 1997 and approximately 14 percent of cancer-related deaths. It occurs primarily in older men but has a relatively good prognosis if detected and treated early enough.

Treatments such as radical prostatectomy and radiotherapy are effective in many patients, and five-year survival rates exceed 60 percent. However, these treatments can be stressful, and side effects include impotence and incontinence.

"We have begun to identify short-term quality of life problems among prostate cancer patients following diagnosis and treatment," Baum said. "However, despite the increasing incidence of this disease and the fact that prostate cancer survivors are a rapidly growing group, little is known about long-term quality of life and response to recurrence and treatment among these men. There also is relatively little known about the impact that recurrence or subsequent treatment for prostate cancer has on quality of life.

"If we understand more about the psychological impact of prostate cancer treatment, we may be able to develop better therapies for managing its long-term effects on men," said Baum, who also directs UPCI's Behavioral Medicine and Oncology Program.

Baum's research will evaluate quality of life experienced by survivors 5-8 years after their treatment for primary prostate cancer.

Men who would like to participate or want to learn more about the study can call Michele Elder at 624-4867.

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Study confirms efficacy of taxol regimen in treating advanced lung cancer

Results from a large, randomized study has confirmed the efficacy of paclitaxel plus carboplatin in treating non-small cell lung cancer (NSCLC).

The University of Pittsburgh Cancer Institute (UPCI) study compared paclitaxel/carboplatin to treatment with cisplatin/etoposide. It enrolled 369 patients with advanced or metastic NSCLC between May 1995 and July 1996; 179 patients received cisplatin/etoposide and 190 received paclitaxel/carboplatin. After initial therapy, patients could receive additional chemotherapy.

"Patients in the paclitaxel arm of the study experienced a greater response rate compared to cisplatin/etoposide, 23 percent versus 14 percent respectively. Patients who received paclitaxel/carboplatin experienced improvement in quality of life from baseline to third course of chemotherapy," said Chandra Belani, Pitt associate professor of medicine and co-director of UPCI's Lung Cancer Program.

Lung cancer represents about 15 percent of cancer cases in the United States — 178,000 new cases in 1997. Lung cancer accounts for over one-fourth of cancer deaths in this country; it is the No. 1 killer by cancer and kills more people than colon, prostate and breast cancer combined. Currently, one half of U.S. lung cancer cases are in men, but the number of women diagnosed each year is increasing and is expected to surpass that in men.

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Pitt awarded $7.7 million for dendritic cell research

The National Cancer Institute has awarded Pitt a $7.7 million, five-year grant to study how dendritic cells participate in generating immunity against cancer cells, inducing transplant tolerance, and modifying auto-immunity that results in diseases such as diabetes and the arthritic condition, scleroderma.

Dendritic cells are the pacemakers of the immune system. They are the first to recognize and process antigens, proteins found on or within intruders such as viruses and bacteria. Dendritic cells introduce these foreign antigens to other specialized cells of the immune system that help to produce antibodies or kill the invaders directly.

"This funding provides us an unprecedented opportunity to expand our studies of dendritic cell biology and its importance in disease," said principal investigator Michael T. Lotze, professor of molecular genetics and biochemistry, and co-director of the University of Pittsburgh Cancer Institute (UPCI)'s biological therapeutics program.

"We have a unique gathering of internationally recognized investigators who are exploring dendritic cell-based therapies at a time when the isolation, culture and application of these cells to human disease have progressed significantly." Olivera Finn, professor of molecular genetics and biochemistry and of surgery, and director of UPCI's program in immunology, is co-principal investigator on the grant.

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Novel form of vitamin K stops cancer cell growth, scientists find

Pitt scientists have discovered how a novel form of vitamin K (called Cpd 5) exerts its cancer-killing effects in primary liver cancers, which are notoriously resistant to chemotherapy.

"Our finding is extremely important if we are to maximize the use of vitamin K compounds against cancer," said Brian Carr, professor of surgery at the Thomas E. Starzl Transplantation Institute and director of the Liver Cancer Center at the University of Pittsburgh Cancer Institute.

"Through our ongoing research, we now know that the vitamin K compounds not only can kill liver cancers, but also can destroy other types of cancer in tissue cultures, including breast cancer and melanoma. They do so by a quite novel growth-regulating mechanism.

"One of the attractive features of this unique compound is that it appears to stop cancer cell growth without producing toxicity," Carr said. "We now are testing this compound against cancers in rats, and given positive results, we hope to begin clinical trials of this agent within two years." Liver cancer is one of the three most common cancers; it killed 15,000 people in the United States in 1997 alone. Major causes include infection with hepatitis B or C or chronic alcohol consumption.

In developed countries, liver cancer may be treated by taking out the area of the liver containing a tumor or by replacing the diseased organ with a transplanted one. However, liver transplantation is costly and often unavailable.

"By providing this modified vitamin K to individuals at known risk of developing liver cancer, we might be able to reduce the incidence of this devastating disease," Carr said. "By treating liver cancer with this agent, we possibly could remove some individuals with this disease from transplant waiting lists, if it is as effective in humans as it is experimentally." The results were published in the May issue of The Journal of Biological Chemistry.

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Researcher to study cognitive effects of chemo in premenopausal women with breast cancer

Pitt nurse researcher Catherine Bender has received a $300,000 grant from the American Cancer Society for her study of cognitive function and reproductive hormones in premenopausal women undergoing adjuvant chemotherapy for breast cancer.

Adjuvant chemotherapy eradicates remaining cancer cells and reduces the risk of cancer recurrence. It has improved the cure rate in premenopausal women with early stage breast cancer. But one side effect is cognitive impairment — deficits in learning, memory and attention, similar to those in elderly women.

"We believe the chemotherapy reduces reproductive hormones, particularly estrogen and progesterone, and this may contribute to cognitive impairment," Bender said.

Her study will determine the short- and long-term effects of adjuvant chemotherapy on learning, memory and attention, and estrogen and progesterone levels in two groups of premenopausal women with breast cancer who receive adjuvant chemotherapy. Those women will be compared with a group of premenopausal women with breast cancer who do not receive adjuvant chemotherapy.