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LOS ANGELES, July 18 (Xinhua) -- U.S. scientists have proven that oncogenes can change normal cells into stem-like cells, paving the way to a safer and more practical approach to treating diseases like multiple sclerosis and cancer with stem cell therapy.In a collaborative study, researchers from the Keck School of Medicine of the University of Southern California (USC), and the Children's Hospital of Orange County (CHOC) in California and Good Samaritan Hospital Medical Center in New York have successfully converted human skin cells into brain cells by suppressing the expression of p53, a protein encoded by a widely studied oncogene. This suggests that p53 mutation helps determine cell fate -- good or bad -- rather than only the outcome of cancer.Oncogenes are generally thought to be genes that, when mutated, change healthy cells into cancerous tumor cells.Study findings were appearing Monday on the website of the American Association for the Advancement of Science (AAAS)."The reality may be more complicated than people think," said Jiang F. Zhong, Ph.D., assistant professor of pathology at the Keck School. "What is a stem cell gene? What is a cancer gene? It may be the same thing.""When you turn off p53, people think the cell becomes cancerous because we tend to focus on the bad thing," Zhong said. "Actually, the cell becomes more plastic and could do good things, too. Let's say the cell is like a person who loses his job (the restriction of p53). He could become a criminal or he could find another job and have a positive effect on society. What pushes him one way or the other, we don't know because the environment is very complicated."Stem cells can divide and differentiate into different types of cells in the body. In humans, embryonic stem cells differentiate into three families, or germ layers, of cells. The reasons why and how certain stem cells differentiate into particular layers are not clearly understood. However, from those layers, tissues and organs develop. The endoderm, for example, leads to formation of the stomach, colon and lungs, while the mesoderm forms blood, bone and heart tissue. In its study, Zhong's team examined human skin cells, which are related to brain and neural cells from the ectoderm.When p53 was suppressed, the skin cells developed into cells that looked exactly like human embryonic stem cells. But, unlike other man-made stem cells that are "pluripotent" and can become any other cells in the body, these cells differentiated only into cells from the same germ layer, ectoderm."IPSCs (induced pluripotent stem cells) can turn into anything, so they are hard to control," Zhong said. "Our cells are staying within the ectoderm lineage."Zhong said he expects that suppressing other oncogenes in other families of cells would have the same effect, which could have critical significance for stem cell therapy. Future research should focus on determining which genes to manipulate, Zhong said.The study is slated to appear in the Proceedings of the National Academy of Sciences later this month, according to AAAS.

BEIJING, Sept. 26 (Xinhua) -- Nobel laureates on Monday cast doubt on a European experiment that purportedly demonstrated the ability of neutrinos to move faster than the speed of light.They made the remarks in Beijing prior to a forum for Nobel laureates."I'm willing to bet money that it's not correct," said Professor George Smoot III, winner of the 2006 Nobel Prize in Physics and a professor at University of California, Berkeley, referring to an experiment result claiming that particles apparently travel faster than light.The experiment reported an anomaly in the flight time of neutrinos, or electrically neutral subatomic particles, from the European Center for Nuclear Research (CERN) in Switzerland to a laboratory located 730 kilometers away in Italy.Particles were clocked transmitting at a speed of 300,006 kilometers per second, about 60 nanoseconds faster than the speed of light.Smoot said that the claims "did not make sense" and should be verified by other scientists first."There are many distortions in physics. You have to have a very high standard to see if something is truly correct," he said.The unverified findings were published on Sept. 22 in the scientific journal Nature. European researchers working in a team called OPERA (Oscillation Project with Emulsion-Racking Apparatus) projected masses of neutrinos from CERN and then collected the particles using a massive detector in Gran Sasso, south of Rome.Other scientists, as well as the OPERA team themselves, have voiced doubts regarding the experiment's results.The findings, CERN claims, could pose far-reaching potential consequences once verified.If correct, the results would bring Einstein's theory of special relativity into question. Under this theory, a physical object cannot travel faster than the speed of light in a vacuum."If really it is right, we have to rethink everything we know," said Chris Llewellyn Smith, former director of CERN.Smith claimed the unprecedented discovery was too exceptional to find proof."If somebody makes a very exceptional claim, then very exceptional proof would need to come from another experiment, saying the same thing. But we don't have the other thing," Smith said.Carlos Rubbia, a Nobel Laureate who won the prize for physics in 1984, is in charge of a team of more than 100 scientists at CERN."What it is pretending to find, in my view, is unbelievably surprising," Rubbia said."Frankly, I have the feeling that this is still a very experimental consideration," Rubbia said.He also believes that revealing the findings to the public was a mistake as it remained an experimental process and no conclusion could be drawn without the results of another experiment.Despite the possibility of verification, Einstein's special theory of relativity will remain valid."I will be very, very surprised that, at last, Einstein will not be the winner," Rubbia said.To achieve a breakthrough, Rubbia has urged for more joint cooperation on verifying the test results. International cooperation on this issue "is a must.""It requires coordination from all nations," said Rubbia.The 2011 Nobel Laureates Beijing Forum will be held from Sept. 28 to 30 under a theme of "innovation and development."

SAN FRANCISCO, July 28 (Xinhua) -- Amazon announced Thursday that it had reached an agreement with NBC Universal to allow its members to view certain movies from Universal Pictures on-line through its movie streaming service.According to the on-line retail giant, Oscar-winning movies such as "Eternal Sunshine of the Spotless Mind," "Gosford Park" and "Elizabeth" as well as other favorites like "Notting Hill" and "Billy Elliot" are part of the pact.The movies will be available to Amazon Prime members through its streaming service Prime Instant Video. Amazon Prime is a membership program that gives subscribers discounts on shipping for a 79 U.S. dollar annual fee.In February, Amazon said it would offer Prime customers unlimited access to an on-line video library. Last Wednesday, Amazon announced an accord with CBS that expanded the video library to more than 8,000 movies and TV shows. It said Thursday that the NBC deal will bring the number to more than 9,000.With the CBS, NBC Universal deals, Amazon steps up its rivalry against other movie streaming services, especially Netflix, a popular on-line and mail-order movie rental company which just boosted prices by 60 percent for some subscribers. Analysts said Amazon is trying to make the pitch to those customers who are disappointed with Netflix.In a second-quarter earnings letter to investors distributed on Monday, Netflix CEO Reed Hastings said Netflix had more than 24.6 million subscribers in the U.S. at the end of June and vastly more streaming content than its competitors."We haven't detected an impact on our business from Amazon Prime," he noted.

WASHINGTON, June 6 (Xinhua) -- Forests in many regions are becoming larger carbon sinks thanks to higher density, U.S. and European researchers say in a new report.In Europe and North America, increased density significantly raised carbon storage despite little or no expansion of forest area, according to the study, led by Aapo Rautiainen of the University of Helsinki, Finland, and published Monday in the on- line, open-access journal PLoS One.Even in the South American nations studied, more density helped maintain regional carbon levels in the face of deforestation.The researchers analyzed information from 68 nations, which together account for 72 percent of the world's forested land and 68 percent of reported carbon mass. They conclude that managing forests for timber growth and density offers a way to increase stored carbon, even with little or no expansion of forest area."In 2004 emissions and removals of carbon dioxide from land use, land-use change and forestry comprised about one fifth of total emissions. Tempering the fifth by slowing or reversing the loss of carbon in forests would be a worthwhile mitigation. The great role of density means that not only conservation of forest area but also managing denser, healthier forests can mitigate carbon emission," says Rautiainen.

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