Word: tau
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...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...
Scientists still do not know, for example, whether Alzheimer's kills nerve cells (neurons) and whether it does so from the inside out or outside in. Supporters of the first scenario believe abnormalities in a protein called tau cause neurons in the brain's memory centers to clutter themselves up with tangled filaments, bringing cellular metabolism to a standstill. Still others think the damage is dealt by an external agent: the so-called beta-amyloid protein that aggregates in the brain, forming fibrous plaques. These plaques in turn injure neighboring neurons, causing them...
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...
...physicists eventually became intrigued with a third idea. Perhaps some electron neutrinos were switching identities, changing by a process called oscillation into muon or tau neutrinos (the two other varieties) en route to Earth. If so, existing detectors could never see them. And while some of the fine print in the laws of physics says that a massless neutrino can't change its stripes, a neutrino with even a tiny bit of mass might. If neutrinos have mass, they can change; conversely, if they can change, they must have mass, despite what textbooks have been saying for decades...