Word: cellular
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Dates: during 2000-2009
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...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...
Logically it would seem that compounds that block the activity of either beta or gamma secretase should slow the progression of Alzheimer's disease. But there are reasons to remain cautious. For one thing, it may turn out that both these secretases play vital roles in other aspects of cellular metabolism, so that interfering with them will come at the price of serious side effects. For another, it is still far from proven that beta amyloid is as central to Alzheimer's disease as, say, cholesterol is to heart disease. Says molecular neurologist Dr. Peter St. George-Hyslop...
...those checks is the T cell's dependence on another cellular player: the antigen-presenting cell. The APC is an omnivorous creature whose job, among other things, is to gobble up microbial invaders. To initiate the immune response, the APC coughs up a molecule from the bug it has eaten, latches on to a helper T cell and "presents" it with a target molecule, instructing the T cell to prepare its troops for war. This activation is tightly controlled; it cannot occur without the lockstep interaction of several proteins on both cells--one of which is known...
...result of chronic high blood pressure, high cholesterol or the deleterious effects of smoking. The body tries to repair the damage, and a kind of internal scab is formed. Years go by, and the scab develops into a fatty deposit, filled with cholesterol, proteins and bits of cellular detritus. Sometimes the plaque is quite stable, and nothing much happens. Other times, for reasons that are still unclear, it becomes inflamed and prone to rupture. If the plaque breaks open, a clot forms, choking off the supply of blood. If the interruption lasts long enough, a heart attack ensues...