Word: cellularized
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...probe cellular gene activity en masse, scientists first isolate the molecules that translate genes into proteins. They then copy these molecules into their corresponding DNA sequences, tag those sequences with fluorescent markers and pour the tagged sequences over the microarray. Active genes in this biochemical stew stick like Velcro to their single-stranded partners on the chip, creating patterns of fluorescent dots that reveal which genes are turned on. "This technology has fundamentally altered how we explore biology," says Dr. Olli Kallioniemi of the NIH, who studies gene expression in cancers...
CELL PHONES Do they or don't they cause brain cancer? After a handful of studies yo-yoed back and forth on the answer, the Cellular Telephone Industry Association tried to seize control of the uncertainty this summer and, they hoped, pre-empt any future lawsuits. (Noted class-action attorneys have already joined an $800 million suit against Motorola.) The association suggested that cell-phone manufacturers voluntarily disclose radiation levels emitted by each unit's antenna. Meanwhile, those who walk and talk at the same time can take solace; the latest studies find no increased risk of brain tumors...
...current attack against resistant strains is multipronged. Some microbiologists are trying to re-engineer the older generation of miracle drugs to get around the mechanisms of resistance. Tetracycline, which kills bacteria by disabling a cellular structure known as the ribosome, is the target of one such effort. Bacteria become resistant to tetracycline, observes Tufts University microbiologist Dr. Stuart Levy, by deploying one protein that serves to shield the ribosome and another that acts as a molecular pump, forcibly ejecting the antibiotic from the cell. Those insights have spawned a line of tetracycline analogs, against which neither the shield...
...look for fresh new antimicrobial agents. Cubist, in Cambridge, Mass., has an injectable form of one such agent--daptomycin--in late-stage clinical trials. Like tetracycline, it was derived from filamentous bacteria that dwell in both soil and water. But daptomycin does not work as tetracycline does by inhibiting cellular metabolism. Rather, it disrupts the conformation of the bacterium's cell membrane, more like penicillin. The way daptomycin does this appears to be unique; in other words, the resistance that disease-causing bacteria have developed to penicillin should not readily transfer to daptomycin...
...Gary Tarpley, who led the team effort that produced the drug. "Because this compound has never been seen by bacteria," he says, "it is extremely unlikely that there is any pre-existing resistance out there." Like tetracycline, linezolid blocks protein synthesis, but it does so much earlier in the cellular cycle. No other antibiotic operates in this fashion, yet another reason to expect resistance to develop more slowly...