Word: tau
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Dates: during 1990-1999
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...detection was indirect: what the physicists actually saw was flashes of light caused by fallout from rare but occasional collisions between neutrinos and water molecules. There were fewer flashes than expected from so-called muon neutrinos, suggesting that some of them had changed into another type, called tau neutrinos. Arcane theory dictates that neutrinos can't change form unless they have mass--though scientists can't say precisely what that mass...
...nerve cells, forming the deposits known as plaques. Among other things, plaques appear to impair the ability of neurons to absorb glucose from the bloodstream, generating an energy crisis inside the cell. A competing hypothesis maintains that Alzheimer's begins not with beta amyloid but with a protein called tau. Abnormal variants of this protein, say scientists, clutter the interiors of neurons with tangled filaments that disrupt cellular metabolism...
...beta amyloid, it is well established, have high rates of Alzheimer's, which lends weight to the beta amyloid theory. But many more people, observes Duke University neurologist Dr. Allen Roses, carry an Alzheimer's-susceptibility gene known as Apo-E4, which produces a protein that appears to affect tau. Individuals who carry two copies of this gene, Roses has shown, have an elevated risk of developing Alzheimer's before age 70. And if they suffer a stroke, warns another report published in last week's J.A.M.A., they are more likely to develop full-blown dementia...
Which version of events is correct? Since both plaques and tangles are found in the brains of Alzheimer's patients, a number of clinicians suspect that tau and beta-amyloid may each play a role, though not necessarily in every patient. For in contrast to the simplistic thinking that dominated the Alzheimer's field only two decades ago, medical researchers now believe this common form of senile dementia is actually a cluster of diseases that, like diabetes and heart disease, may have more than one fundamental cause...
...world of science, confusion is often a sign of progress, and this may prove to be the case here. "The best," predicts Washington University neuropathologist Dr. Leonard Berg, "is yet to come." Already researchers are rushing to develop compounds that take aim at the tau and beta-amyloid proteins. They are also re-examining existing drugs that may offer therapeutic pportunities. Some experts, for example, speculate that antioxidants such as vitamin E and anti-inflammatories such as ibuprofen could help shield neurons from chemical damage. Others have seized on tantalizing hints that the female hormone estrogen may delay the onset...