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Burgess Response To President Obama's Answer To His Question On Medical Liability Reform
During today"s White House online town hall on health care, a question was submitted by Congressman Michael C. Burgess, M.D. (R-Texas), Chairman of the Congressional Health Care Caucus. Following President Obama"s response to the question on medical liability reform, Congressman Burgess issued the following statement:
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Why Some Tumors Don't Respond To Radiation And Chemotherapy
A tightly controlled system of checks and balances ensures that a powerful tumor suppressor called p53 keeps a tight lid on unchecked cell growth but doesn"t wreak havoc in healthy cells. In their latest study, scientists at the Salk Institute for Biological Studies suggest just how finely tuned the system is and how little it takes to tip the balance.
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Swine Flu: Health Departments Get Mixed Marks For Using Web To Communicate About Crisis, Study Finds
State and local health departments get mixed marks for efforts to convey information about the H1N1 virus to the public using their Web sites immediately after U.S. officials declared a public health emergency in April, according to a new RAND Corporation study.
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The Evolutionary Foundation Of Genomic Imprinting In Lower Vertebrates

A Chinese scientist group working in College of Life Science, Zhejiang University, has shown that, as mammalian Igf2 CpG island, goldfish Igf2 CpG island has a parental differentially methylated region (DMR). These results indicate that the evolutionary foundation of genomic imprinting exists in lower vertebrates and genomic imprinting should not be considered as a unique evolutionary event of mammals. The study is reported in volume 54 (Issue 8, April, 2009) of Chinese Science Bulletin. Genomic imprinting has been identified in eutherians, marsupials and flowering plants, but no endogenous imprinted gene has been reported in other vertebrates and invertebrates. Therefore, genomic imprinting is thought a unique phenomenon of placental mammals and a regulatory mechanism to keep a balance of supply and demand for maternal nutrients between mother and fetus in mammalian species. However, how genomeic imprinting was originated, established and maintained during vertebrate evolution remains unclear. In this study, the authors examined the methylation status of the teleost homologue of mammalian imprinting gene Igf2 during gametogenesis. Their results showed that, as mammalian Igf2 CpG island, goldfish Igf2 CpG island was a parental differentially methylated region that was hypermethylated in sperm but unmethylated in eggs. The authors also indicated that, unlike mammalian imprinting gene DMR, the unmethylated DMRñ€€of maternal allele could not resist methylation reprogramming and started de novo methylation at the cleavage stage, while the paternal Igf2 allele appeared to maintain its paternal methylation imprints during embryogenesis. These results suggested that the parent-specific methylation of goldfish Igf2 DMR might be a primitive genomic imprinting in the early period of vertebrate evolution. The investigation "provided the first molecular evidence that the evolutionary foundation of genomic imprinting exists in lower vertebrates", said one of the journal reviewers. This work was supported by of the National Natural Science Foundation of China (Grant No. 30430370) and the State Key Basic Research Project of China (2004CB117401). Reference: Xie B., Zhang L., Zheng K & Luo C. The evolutionary foundation of genomic imprinting in lower vertebrates. Chin Sci Bull. 2009; 54(8): 1354-1360. C. Luo Science in China Press


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