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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, July 14 (Xinhuanet) -- European music service Spotify is set to launch in the United States on Thursday, according to media reports.The streaming service will be available in the morning by invitation and through subscription."Spotify is a new way to listen to and manage your music, discover new tracks and share songs and playlists with friends – music whenever you want it, wherever you are," the company said in a statement.Spotify's streaming music and subscription service have long been popular in Europe since its launch in late 2008, and the company has been aiming for a US launch for nearly as long.Spotify has inked agreements with Sony Corp Music Entertainment, EMI Music, and Vivendi SA's Universal Music Group in the last few months. It is expected to close a deal with Warner Music Group by launch or soon after, according to a source.

LOS ANGELES, July 18 (Xinhua) -- The spacecraft Dawn of the National Aeronautics and Space Administration (NASA) has returned the first close-up image of the giant asteroid Vesta after entering its orbit for the first time last week, the Jet Propulsion Laboratory (JPL) announced on Monday.The image taken for navigation purposes shows Vesta in greater detail than ever before, said JPL in Pasadena, California.On July 15, Dawn became the first probe to enter orbit around an object in the main asteroid belt between Mars and Jupiter.When Vesta captured Dawn into its orbit, there were approximately 9,900 miles (about 16,000 kilometers) between the spacecraft and the asteroid.Vesta is 330 miles (about 530 kilometers) in diameter and the second most massive object in the asteroid belt.NASA's Dawn spacecraft obtained this image with its framing camera on July 17, 2011. It was taken from a distance of about 9,500 miles (15,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 0.88 miles (1.4 kilometers). Ground- and space-based telescopes have obtained images of Vesta for about two centuries, but they have not been able to see much detail on its surface."We are beginning the study of arguably the oldest extant primordial surface in the solar system," said Dawn principal investigator Christopher Russell from the University of California, Los Angeles, which is responsible for Dawn's mission science. " This region of space has been ignored for far too long. So far, the images received to date reveal a complex surface that seems to have preserved some of the earliest events in Vesta's history, as well as logging the onslaught that Vesta has suffered in the intervening eons."Vesta is thought to be the source of a large number of meteorites that fall to Earth. Vesta and its new NASA neighbor, Dawn, are currently approximately 117 million miles (about 188 million kilometers) away from Earth. The Dawn team will begin gathering science data in August.Observations will provide unprecedented data to help scientists understand the earliest chapter of the solar system and pave the way for future human space missions, according to JPL."Dawn slipped gently into orbit with the same grace it has displayed during its years of ion thrusting through interplanetary space," said Marc Rayman, Dawn chief engineer and mission manager at NASA's JPL. "It is fantastically exciting that we will begin providing humankind its first detailed views of one of the last unexplored worlds in the inner solar system."Although orbit capture is complete, the approach phase will continue for about three weeks. During approach, the Dawn team will continue a search for possible moons around the asteroid; obtain more images for navigation; observe Vesta's physical properties; and obtain calibration data.In addition, navigators will measure the strength of Vesta's gravitational tug on the spacecraft to compute the asteroid's mass with much greater accuracy than has been previously available, according to JPL.Dawn will spend one year orbiting Vesta, then travel to a second destination, the dwarf planet Ceres, arriving in February 2015. The mission to Vesta and Ceres is managed by JPL for the agency's Science Mission Directorate in Washington.Dawn is a project of the directorate's Discovery Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alaska.

BEIJING, Sept. 21 (Xinhuanet) -- China will launch an unmanned module next week, paving the way for a planned space station, a spokesman for the space program said on Tuesday.Tiangong-1, or "Heavenly Palace 1", will blast off from Jiuquan Satellite Launch Center in Gansu province between Sept 27 and 30, the spokesman said.The 8.5-ton module, and the Long March II-F rocket that will carry it skyward, were positioned onto the launch pad on Tuesday, signaling that the project has entered the final preparation stage."Scientists will conduct final tests in the next few days before injecting propellants for the launch," Cui Jijun, director of the Jiuquan Satellite Launch Center, said.The program spokesman said that Tiangong-1 will serve as "a target spacecraft" for rendezvous and docking experiments.It will also work as "a platform to test long-term unmanned and short-term manned operations", he said.Technical and medical experiments will provide crucial data ahead of the building of the space station (scheduled for 2020).Three rendezvous and docking experiments will be conducted.An unmanned Shenzhou-VIII craft will be launched later this year to dock with Tiangong-1. In 2012, Shenzhou IX and Shenzhou X will blast off to complete at least one manned docking.Jiao Weixin, a space scientist at Peking University, said that rendezvous and docking - vital maneuvers for manned programs - are hard to master."Rendezvous and docking are difficult because it is like asking two racing cars to keep a distance of 1 meter between them," he said.The mission requires two craft, traveling at speeds of 28,000 km/h, to enter the same orbit and connect with precision, he said.The China Manned Space Engineering Office rescheduled the launch of Tiangong-1 after the failed launch of an experimental orbiter last month.The spokesman said that the carrier rocket to blast off with Tiangong-1 atop has been modified.Only the United States and Russia have mastered rendezvous and docking technology, said Pang Zhihao, deputy editor-in-chief of the magazine Space International.Spacecraft developed by Europe and Japan have utilized US and Russian technology to dock with the International Space Station, he added.

concerned about weaker economic growth being a reality for most advanced economies."Further mis-steps from European and US policymakers risk converting the cracks in their economies into a much deeper global system crisis which would have worrying economic and?social consequences," he warned.But Smith, whose bank is focusing on Asia to drive profit growth, remains optimistic for the outlook in the Asia-Pacific region.He said that the fact is that Australia is incredibly well positioned because of the nation's linkage to Asia, which remains the best performing part of the global economy.His comments came after ANZ reported a 1.45 billion U.S. dollars underlying profit for the June quarter, up 1.3 percent compared to the March quarter.