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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.

SAN FRANCISCO, June 14 (Xinhua) -- Apple updated its online store on Tuesday to begin offering unlocked models of iPhone 4 in the United States for the first time."The unlocked iPhone 4 requires an active micro-SIM card that you obtain from a supported GSM wireless carrier," said Apple in the product description. The iPhone requires a smaller version of the standard SIM (Subscriber Identity Module) card.Started at 649 U.S. dollars for the 16 GB version, the unlocked model is a GSM phone, which means, in the United States, the phone runs on networks of T-Mobile or AT&T, although it can only send data over T-Mobile's old EDGE network, not its 3G network and the faster HSPA+ network.Verizon and Sprint, the other two major U.S. wireless carriers, both use CDMA networks that do not use SIM cards.The iPhone 4 has been sold unlocked in other countries. For frequent international travelers, an unlocked iPhone means they just need to pop in a micro-SIM card for whichever country they are going, avoiding provider's high international fees.According to Apple, iPhone sales grew 113 percent year over year in the second quarter of its fiscal 2011, reaching a record high of 18.65 million units.

HOHHOT, Aug. 27 (Xinhua) -- A 5,000-year old rock carving in north China's Inner Mongolia Autonomous Region depicts a falling meteor, said archaeologists on Saturday.A rock on the side of Dahei Mountain in the city of Chifeng has images of people, domed houses and a fire ball with a long tail falling from the sky engraved on it, said Wu Jiacai, head of the Inner Mongolia rock paintings protection association."I believe it shows prehistoric people returning at dusk from a hunting trip to their domed houses, as a meteor falls from the sky," Wu shared his findings at the 6th Hongshan Cultural Forum that runs from August 25 to 27.He added that in the same location several years ago, another set of carvings were found showing people fleeing, snakes slithering and birds flying away, which might be what happened after the meteor hit the earth.The area has about 1000 carvings all believed to be made by the Neolithic Hongshan people, Wu said."The pictures can shed some light on the disappearance of the Hongshan culture, which was quite developed," Wu said.

BANJUL, June 24 (Xinhua) -- Deputies at the Gambian National Assembly (parliament) on Friday passed a new bill entitled the "Food Safety and Quality Bill 2011".Under the new act, food operators are obliged to ensure food safety, quality production, processing and distribution within the business under their control and that their products must satisfy the requirements and regulations as demanded.Submitting the motion before deputies, Vice President and Minister for Women Affairs Isatou Njie-Saidy warned that the well- being of "our citizenry is at stake.""Giving our continuous drive to place health care on top of our development agenda, we call on all and sundry to join the bandwagon in the implementation of this bill," she said.She told deputies that the bill and the establishment of the Gambia Food Safety and Quality Authority is consistent with the regulation worked out by the West African bloc ECOWAS on the health and safety of plants, animals and food in the region.The Gambia Food Safety and Quality Authority being established by this bill will be the sole national competent authority having unitary responsibility for food safety and quality, she declared."In order to achieve the general objectives of a high level of protection of human health and life, measures applied under this Act shall be based on risk assessment," she added.

BEIJING, August 1 (Xinhuanet) -- U.S. researchers have discovered a genetic mutation unique to African Americans that links to heighten their asthma risk, according to reports published on Sunday in the journal Nature Genetics.Researchers of University of Chicago found a gene, PYHIN1, and its variations may account for asthma risk in people of African descent. In their study, they examined data from nine previous genome-wide association studies, totaling more than 2 million single nucleotide polymorphisms in 3,246 asthma patients and 3,385 control patient, 1,702 patient-parent groupings, 355 family-based cases, and 468 family-based controls.In the study, the researchers found that between 26 percent and 29 percent of people of African-descent carried at least one copy of the gene.  In particular, one polymorphism of the gene was 34 percent more likely found in African-American and Afro-Caribbean people with asthma.  More interestingly, this variant of the gene is rarely found in Caucasian people and in Latino population, it was found in less than 5 percent.This new variant is part of a family of genes linked with the body's response to viral infections. It is thought to be involved in interferon signaling, which could influence the occurrence of asthma.The team stressed that each gene variant on its own plays only a small role in increasing asthma risk, but that risk could be multiplied when combined with other risk genes and with environmental factors.

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