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Further steps towards artificial ovule and spermatozoon
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British scientists report that the laboratory had received human stem cells oxygen in the form of special cells, which produce ovule and spermatozoon.
The work of several groups of scientists showed that a small number of stem cells spontaneously become germ gametes, if they leave for a free differentiation. In his latest study Behrooz Aflatunan and his colleagues at the University of Sheffieldscom received germ gametes, some of them have begun to make sperm proteins, and the rest of its characteristics resemble ovule.
However, until such time as doctors will be able to even consider that replicate this technology for people who are far from being achieved. Researchers, for example, has not yet proved that the cells emit sperm proteins, shared correctly, contained only one set of chromosomes like normal sperm. The team presented the results of his study at a meeting of the European Community to study human reproduction and embryology, held on Monday in Copenhagen. Dreams that produce sperm and ovule cells outside the human body remain at the moment dreams.
While progress in the work of mice bigger than in the work of the people even mice scientists are difficult to achieve through repetition on the achievements of the past. The idea is that once it is available for use by people who can not have children. It is the removal of cells from the body, receipt of stem cells through therapeutic cloning, and then formation of sperm or ova. Possibility to get eggs to the laboratory to be another serious problem in the use of therapeutic cloning, - it is a huge need for ejaculation.
In 2006, a team of American scientists have cells such as ovule from stem cells mouse, and Japanese scientists have sperm cells. It does not require any special features: stem cells to differentiated into various types of cells, and some of this has evolved germ gametes. In the same year, a group of scholars, under the leadership of George Daily at Harvard Medical School in Boston, USA, to be germ cells derived from stem cells in normal mouse ovule to see whether they do inpregnate. Half of the embryos reach double-ply stage, and a fifth to embryonic bladder.
However, during the two years never as a result of the transplant bladder embryonic mouse cows started to develop pregnancy, One panelist Paul Roux. The Orly Lacam-kaplana of Monash University in Australia, said at the conference Initially they tried to get a cell mouse ovule using the same method, by the team LeRoux tried unsuccessfully to apply in 2006, but now succeeded with the help of samples, received from the mouse prepubescent age. "We are trying to replicate the natural growth factors," says Lacam-kaplan.
It seems that in the foreseeable future attempts to obtain sperm and egg remain in a purely academic interest, because still many obstacles to overcome not. This does not apply unless the White Crow "in the scientific world, as Severino Antinori, a controversial character, with the insemination and now settled Sidney, his work is not prohibited. Here, he said New Scientist, it has helped three men unable to produce sperm, taking stem cells from donor cell and then entering them in the testicles patients.
If this is true, then it is very dangerous-in mice stem cells are cancerous (malignant) growth. Scientists said that the biopsy showed no signs of cancer, but some of the eggs regenerate, even though none of the men started to form sperm. Now, he said, he intends to have germ cells using the Daily and Aflatunian and put them in the testicles instead of stem cells.
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