Space studies also meet health needs on Earth
■ Research on astronauts may lead to advances in treating bone loss, asthma and cancer.
By Susan J. Landers — Posted April 13, 2009
Washington -- Researchers are making connections between the health risks of dust on the moon and asthma on Earth; between the sleep problems of astronauts and those of shift workers; and between emergency medical care in space and in war zones.
Several researchers funded by the Houston-based National Space Biomedical Research Institute came to Capitol Hill March 25 to demonstrate solutions they have devised for health problems that might develop during space exploration but could apply to life on earth as well.
NSBRI works in partnership with NASA to sponsor research at universities across the country -- an enterprise supported by policy of the American Medical Association, which encourages medical research that results in potential health care benefits in manned space flights as well as in overall medicine and patient care.
For instance, G. Kim Prisk, PhD, DSc, professor of medicine, physiology and radiology at the University of California, San Diego, brought to the briefing a container of simulated lunar dust resembling black talcum powder, modeling the substance central to his efforts to increase understanding of the lung's inner functioning.
With properties comparable to quartz dust, moon dust is thought to be toxic. Prisk's goal is to help determine how to minimize astronauts' exposure on the dusty lunar surface. Although no astronaut has yet developed a lung disorder that can be traced directly to space flight, the next round of lunar missions will last longer than those of earlier years, thus posing a greater risk. Specifically, even if the lungs can clear many small particles, those that cling to the lungs' periphery aren't easily expelled, Prisk said.
Thus the research not only is important to the health of people on space missions, but it also has significant down-to-earth implications. Prisk's work will provide a better understanding of how inhaled particles, including asthma medications, distribute themselves within the lungs. "If we learn how to target drugs to specific areas inside the lung, it will be possible to achieve optimal results with small quantities of drugs delivered to exactly the right place in the lung, minimizing side effects," he said.
Drug companies are interested in devising inhalers that bring this about. "Aerosol size is now being talked about, whereas five or six years ago, no one paid attention," he said. "We know a lot more about that now as a result of these studies."
George C. Brainard, PhD, professor of neurology at Jefferson Medical College in Philadelphia, also participated in the demonstration, bringing to the event a series of fluorescent lights with bluish tints.
Dr. Brainard uses the glowing tubes as part of his exploration of ways to combat sleep loss and disturbed circadian rhythms that can compromise alertness -- a danger for shift workers whether they're astronauts, truckers, pilots or medical residents. Blue-tinted light is emerging as an effective way to counter these disruptions, he noted. When a person is bathed in light that is more blue-tinged than the traditional red tints of office lights, melatonin production rises and signals that it's time to sleep.
Although Brainard is working with fluorescent lighting, he noted that LEDs, or light emitting diodes, are the way of the near future for use in space and expects they will take over the home market within 10 years. They are ideal for space travel, as they are lightweight, consume less energy and emit less heat than do fluorescent bulbs. And since they contain no mercury, they also are safer.
Yi-Xian Qin, PhD, director of the Orthopaedic Bioengineering Research Lab at Stony Brook University Medical Center in New York, is researching bone loss, a key health problem both for astronauts who spend time in zero gravity and for the aging population. Osteoporosis is a major public health threat for 44 million Americans, according to the National Institute of Arthritis, Musculoskeletal and Skin Disorders.
Qin is working on new ultrasound technology that can assess bone beyond the usual mineral density. The technique is called Scanning Confocal Acoustic Navigation, or SCAN, and it can assess bone strength, structure and stiffness.
He expects to develop a small mobile unit that would be easy to use in medical clinics as well as during space missions.
Meanwhile, in results on a much larger scale, solar radiation research by Ann R. Kennedy, DSc, professor of radiation biology and research oncology at the University of Pennsylvania School of Medicine, is playing the dual role of identifying ways to protect astronauts from bursts of solar radiation, a serious threat on space missions, and minimizing side effects associated with radiation therapy in cancer patients.
Her NSBRI project aided in the development of a massive proton radiation therapy center at the University of Pennsylvania Health System. The new, three-story center is expected to begin treating patients -- likely 200 to 250 per day -- in the fall.
In another project, Babs Soller, PhD, professor of anesthesiology at the University of Massachusetts Medical School in Worcester, has developed a wearable biosensor that will enable astronauts to continually assess their own metabolic status and oxygen consumption during space exploration. The tool will help ensure that they do not exhaust these supplies.
The same sensor will help military medics triage casualties and monitor patient status, Soller said. Physicians also may use the sensors to help care for critically ill patients.