Word: celling
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Dates: during 1990-1999
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Scientists have known for more than two decades that cancer is a disease of the genes. Something scrambles the Dna inside a nucleus, and suddenly, instead of dividing in a measured fashion, a cell begins to copy itself furiously. Unlike an ordinary cell, it never stops. But describing the process isn't the same as figuring it out. Cancer cells are so radically different from normal ones that it's almost impossible to untangle the sequence of events that made them that way. So for years researchers have been attacking the problem by taking normal cells and trying to determine...
Until now. According to a report in the current issue of Nature, a team of scientists based at M.I.T.'s Whitehead Institute for Biomedical Research has finally managed to make human cells malignant--a feat they accomplished with two different cell types by inserting just three altered genes into their DNA. While these manipulations were done only in lab dishes and won't lead to any immediate treatment, they appear to be a crucial step in understanding the disease. This is a "landmark paper," wrote Jonathan Weitzman and Moshe Yaniv of the Pasteur Institute in Paris, in an accompanying commentary...
...dramatic new result traces back to a breakthrough in 1983, when the Whitehead's Robert Weinberg and colleagues showed that mouse cells would become cancerous when spiked with two altered genes. But when they tried such alterations on human cells, they didn't work. Since then, scientists have learned that mouse cells differ from human cells in an important respect: they have higher levels of an enzyme called telomerase. That enzyme keeps caplike structures called telomeres on the ends of chromosomes from getting shorter with each round of cell division. Such shortening is part of a cell's aging process...
...More promise may lie in a sort of mimicry, studying the body?s own approach to fighting cells that go bad ? and Thursday saw some success on that front too. Publishing in Science magazine, a team from the M.D. Anderson Cancer Center in Houston have identified a protein, called Fas ligand, that they think is the body?s own treatment for skin cancer from within. You may know it as peeling. "The body?s traditional respose to mutation is ?You change, you die,?" says Gorman. "When a skin cell sustains enough sun damage to its DNA that it may turn...
...hours (the length of a school day) demanded a large battery, which the full keyboard forced down to the machine's bottom lip. The design guys, meanwhile, had decided that the perfect latch was no latch at all, just a clamshell top that clicked securely shut, like a cell phone. The engineers by this point realized that the heavy battery made the bottom dense enough to handle the latchless...