Word: celling
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...Battle Joined That hidden power in each of us did not become obvious until 1963, when Canadian researchers Ernest McCulloch and James Till first proved the existence of stem cells, in the blood. These cells possess the ability to divide and create progeny - some of which will eventually expire, others that are self-renewing. The pair irradiated mice, destroying their immune cells. They then injected versatile bone-marrow cells into the animals' spleens and were surprised to see a ball of cells grow from each injection site. Each mass turned out to have emerged from a single stem cell, which...
That discovery led, 35 years later, to James Thomson's isolation of the first human embryonic stem cells, at the University of Wisconsin in 1998. And that milestone in turn inspired researchers to think about directing these cellular blank slates to eventually replace cells that had been damaged or were depleted by disease. The key lay in finding just the right recipe of growth factors and nutrients to induce a stem cell to become a heart cell, a neuron, an insulin-making cell or something else. It would take decades, the researchers all knew, but new therapies were sure...
Then, in 2001, everything changed. The use of discarded embryos made embryonic-stem-cell research deeply controversial in the U.S. Citing moral concerns, then President Bush restricted federal funding for the study of human embryonic stem cells. Under the new policy, U.S. government funds could be used only to study the dozens of embryonic cell lines already in existence - many of which proved not to be viable...
...decision sent some leading scientists abroad, to Britain, Singapore and China, where the governments were more receptive to their work. Others who stayed behind but lacked private funding shifted their attention from embryos to the less versatile adult stem cells. Federally backed scientists, like Melton, who continued embryonic work were forced to adopt a byzantine system of labeling and cataloging their cell cultures and equipment so that government money was not used to grow forbidden cells - and government microscopes were not even used to look at them...
Those days may soon be over. Barack Obama campaigned on a promise to lift the research ban and support "responsible oversight" of the stem-cell field. For scientists, that means "we can stop the silliness," says Melton...