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In the News |
Recent Advances from the NHLBI |
The House and Senate Appropriations Subcommittees on Labor, Health and Human Services, and Education are working on their respective appropriations bills for the NIH for Fiscal Year (FY) 2003. Dr. Ruth Kirschstein, Acting Director, NIH, and the Directors of the various NIH Institutes and Centers, participated in an overview hearings with the House and Senate subcommittees on March 13 and 21, respectively. Dr. Kirschstein and other Directors also met with the House subcommittee for "theme hearings" on specific topics:
Dr. Lenfant was invited to speak during the Disease Prevention and Health Promotion hearing on April 16. He presented several examples of NHLBI activities that bring research results to local communities and described ongoing collaborations to allow the Institute's messages to reach people of all ages and backgrounds.
Researchers have cloned and identified the role of a gene that, in the presence of heart failure, appears to cause irregular heart beats that can lead to sudden cardiac death. Although the study was conducted in mice, the same gene regulates electrical currents that are vital to sustaining a normal rhythm in the human heart. Study coauthor Dr. Ching-Feng Cheng, University of California, San Diego, explained that the gene functions like an electrical switch; during heart failure, the switch disrupts current flow, leading to malignant heart rhythms and sudden death. He also noted, however, that sudden cardiac death may be caused by a wide spectrum of underlying mechanisms. "The challenge," he said, "is to identify the key molecular switches that lead to the disease, and to design new ways to treat complex human cardiac diseases."
Despite several serious side effects, a type of implantable heart pump, called a left ventricular assist device, can extend and improve the lives of terminally ill patients with end-stage heart failure who are not eligible for cardiac transplantation. "This study is an initial step in demonstrating the feasibility of restoring or replacing heart function for extended periods of time," said Dr. John Watson, director of the NHLBI Clinical and Molecular Medicine Program and study coauthor. Heart failure affects an estimated 4.7 million Americans, and 550,000 new cases are diagnosed each year. Dr. Lenfant commented, "This compelling study shows that even with a high rate of complications, a left ventricular assistance device can provide a significantly longer and better quality of life in extremely ill heart failure patients for whom a poor quality of life and death are certain."
For the first time scientists have corrected sickle cell disease in mice using gene therapy. "Scientists have been working to accomplish this since the creation of an animal model for sickle cell disease several years ago. Although much more research is needed before human application, this is a significant achievement that brings us closer to human gene therapy for what is a very serious genetic blood disorder," said Dr. Lenfant. The next step is to see how safe and effective the gene transfer process is in larger animals more similar to humans.
Currently, the only cure available is bone marrow transplantation, which requires a healthy, matched sibling donor, and only approximately 18 percent of children with sickle cell disease qualify.
"Code Red," "Ozone Action Day," and other terms describing poor air quality in a community usually are associated with an increase in respiratory ailments. Now, researchers have shown that invisible air pollutants so small that they can evade the lungs' normal defense mechanisms and get into the bloodstream may trigger a heart attack as little as 2 hours after being inhaled. Although it is too early to predict what medical interventions might be effective in preventing heart attacks triggered by fine-particle exposure, some recent data suggest that the particles may cause inflammation and increase levels of certain proteins that cause clots to form. Year-round processes such as combustion in automobile engines, power plants, and refineries cause fine-particulate air pollution, but the associated health concerns are largely summer phenomena. The study's co-author, Douglass W. Dockery, Sc.D., professor of environmental epidemiology at Harvard School of Public Health, advises people to "avoid outdoor activity on hot, hazy days," because when people exercise outside, their increased respiratory activity also increases the amount of particles that are absorbed into the blood stream. But don't use that as an excuse for not going to the gym you joined as part of your New Year's Resolution; air conditioning can reduce indoor concentrations of the pollutants by 30-50 percent.