Word: stems
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Dates: during 1990-1999
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According to Massaquoi, the problems in Sierra Leone stem from the civil war in Liberia. The U.S. government established Liberia by sending previously enslaved blacks there and allowing them to rule...
Doctors also saw obstacles, though. One of them was a U.S. Congress skittish about research on stem cells taken from unwanted human embryos and aborted fetuses. Indeed, last week 70 lawmakers asked in a firmly worded letter that the Federal Government ban all such work...
...grow your own" organs is already upon us, as researchers have sidestepped the stem-cell controversy by making clever use of ordinary cells. Today a machinist in Massachusetts is using his own cells to grow a new thumb after he lost part of his in an accident. A teenager born without half of his chest wall is growing a new cage of bone and cartilage within his chest cavity. Scientists announced last month that bladders, grown from bladder cells in a lab, have been implanted in dogs and are working. Meanwhile, patches of skin, the first "tissue-engineered" organ...
...have scientists managed to do all this without those protean stem cells? Part of the answer is smart engineering. Using materials such as polymers with pores no wider than a toothbrush bristle, researchers have learned to sculpt scaffolds in shapes into which cells can settle. The other part of the answer is just plain cell biology. Scientists have discovered that they don't have to teach old cells new tricks; given the right framework and the right nutrients, cells will organize themselves into real tissues as the scaffolds dissolve. "I'm a great believer in the cells. They...
...monitors tissue-engineering efforts for the FDA. "Any problem that requires lots of cell types 'talking' to one another is really hard," she notes. Bone and cartilage efforts are much closer to fruition, and could be ready for human trials within two years. And what of those magical stem cells that can grow into any organ you happen to need--if the law, and biologists' knowledge, permit? "Using them," says Sefton, "is really the Holy Grail...