Developments to Watch
THE BREATH OF LIFE--THANKS TO A CHIP
THE SEARCH FOR BETTER ways to deliver drug treatments is a critical issue in asthma, a chronic respiratory ailment that affects 15 million people in the U.S. and kills 5,000 each year. Although vastly improved asthma drugs have been introduced in recent years, they must still be breathed in through small devices called metered-dose inhalers (MDIs) that are notoriously tricky to use. Patients must carefully coordinate their breathing with the pumping action to ensure the right dosage--a technique that 70% of asthmatics fail to master.
Aradigm Corp. of Hayward, Calif., has just launched a smart alternative--an MDI with a built-in microprocessor. Its SmartMist device uses red and green indicator lights to guide patients' breathing and to automatically dispense the drug once it senses the desired flow rate is reached. The microchip also stores data for two to three months on the patient's dosage and inhalation patterns, which can be downloaded by physicians to monitor treatment.
Aradigm says that clinical studies show that asthma patients using the SmartMist device achieve correct dosing 90% of the time, compared with 45% with conventional MDIs.EDITED BY CATHERINE ARNSTReturn to top
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A WORM FOR ALL SEASONS
NEXT TIME YOU COMPLAIN about the heat, keep in mind the poor Pompeii hydrothermal vent worm. Scientists report in the journal Nature that this four-inch-long creature, which lives 1 1/2 miles down in the ocean west of Costa Rica, survives greater extremes of heat and cold than any other creature. Its head typically sits in water averaging 72F while its tail rests in a worm hole where the temperatures soar as high as 176F.
The Pompeii worm is the most extreme example yet found of an "extremophile"--an organism tough enough to thrive in hellishly hot, cold, or high-pressure environments. Until scientists learned about the home life of the worm, the most heat-hardy creature was thought to be the Sahara Desert ant, which can survive in temperatures as high as 131F.
University of Delaware biologist Craig S. Cary, along with researchers from Rutgers State University in New Jersey and Diversa Corp. in San Diego, contend that enzymes secreted by bacteria on the Pompeii worm's surface should be just as heat-resistant. These enzymes could become useful catalysts for a wide range of industrial processes, including oil recovery and drug development. Diversa has already found that one of the bacteria on the worm is closely related to H. pylori, which is known to cause ulcers in humans.EDITED BY CATHERINE ARNSTReturn to top
COUNTING THE TROOPS IN THE HIV FIGHT
SCIENTISTS KNOW THAT THE AIDS VIRUS TOUCHES OFF AN urgent race in the body, destroying vast numbers of disease-fighting cells each day while the immune system tries to replace them. Researchers have been able to make only rough estimates of the rate of casualties and reinforcements, based on how cell counts rise when drugs control the virus. That leaves a crucial question over how patients best fight off AIDS: by making new cells faster or by mounting a more effective assault on the virus?
Enlightenment may be near. Dr. Marc K. Hellerstein, associate professor at the University of California, Berkeley, has a method for precisely measuring cell creation. He replaces a hydrogen atom on glucose molecules with the heavier isotope, deuterium, and then gives them to patients. Since glucose is a DNA building block, new immune cells will contain deuterium. Researchers can take cell samples, test for deuterium, and calculate the proportion of new cells. The method, which already shows that making more cells seems to be the key to fighting the virus, is being commercialized by SpectruMedix Corp. in State College, Pa.By John Carey EDITED BY CATHERINE ARNSTReturn to top