Word: nucleus
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...through a process called parthenogenesis, sometimes referred to as virgin birth, since development is sparked spontaneously from the egg alone, rather than from the union of egg and sperm. Parthenogenesis is always a risk during nuclear transfer, since the process involves extensive manipulation of the egg and its nucleus. At the time that Hwang's original paper was published in Science, stem cell researchers raised the possibility that the cells had been generated by the egg alone, but the limited genetic analysis that Hwang provided appeared to rule it out. But, says Daley, "the data they presented was either wrong...
...years, many stem-cell researchers sought to accomplish that through nuclear transfer-transplanting an adult cell's nucleus into an egg that had been emptied of its own genetic material. This process is expensive and difficult, and so far no one has been able to pull it off in humans. Yamanaka never tried. Starting with a tiny team in 1999 at the Nara Institute of Science and Technology-he moved to Kyoto in 2004-Yamanaka focused on finding the genes that could persuade an adult cell to regress on its own to an embryonic state, without the messy mechanics...
...meantime, Eggan's group has provided an alternative method for generating customized stem cells that would take advantage of the early-stage embryos frozen in IVF centers around the country. The most reliable way of generating patient-specific stem cells remains nuclear transfer-taking the nucleus from a patient's skin cell and inserting it into an egg that has had its nucleus removed. This hybrid then begins to divide, and within a few days, generates stem cells that are genetically identical to the patient. The problem, however, as Eggan puts it, is that "there are never any extra unfertilized...
...feuding Shi'ite clans, smuggling and narcotics production. When Israel invaded Lebanon in June 1982, Toufeili was in Tehran and helped organize the deployment in Lebanon of the Iranian Revolutionary Guards who recruited and trained hundreds of young local Shi'ites to fight Israel's occupation, thus creating the nucleus of Hizballah...
...gave subjects $20 each and, while they were in the fMRI machine, presented them with pictures of 80 products, each followed by a price. Subjects then had the option of purchasing each item on display. As they viewed products they preferred, Knutson saw activity in the nucleus accumbens, a region of the brain involved in anticipating pleasant outcomes. If, on the other hand, the subjects thought the price of these items was too high, there was increased activity in the insula-- an area involved in anticipating pain. "The idea is that if you can look into people's brains right...