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A small element from the Mason-Pfizer monkey virus
genome makes human immunodeficiency virus type 1 expression and replication
Rev-independent. 总被引:29,自引:2,他引:29
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M Bray S Prasad J W Dubay E Hunter K T Jeang D Rekosh M L Hammarskj?ld 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(4):1256-1260
Replication of human immunodeficiency virus type 1(HIV-1) is dependent on the viral Rev protein. This protein acts in concert withthe cis-acting rev-responsive element present in intron-containing RNAs tofacilitate nuclear export of these RNAs. Here we show that a cis-acting219-nucleotide sequence from an unrelated "simple" retrovirus,Mason-Pfizer monkey virus (MPMV), enables Rev-independent HIV-1 replication.This sequence is present in an untranslated region near the 3' end of theMPMV genome. The MPMV element is also able to efficiently substitute for Rev inexpression of Gag/Pol and Env proteins from subgenomic constructs. Wehypothesize that the MPMV element functions by interacting with a cellularfactor that plays a role in mRNA transport analogous to that of the Rev protein.It might be possible to exploit this element in the development of an HIVvaccine. 相似文献
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Housing has a major effect on the health and wellbeing of individuals. There are an estimated 40 000 more deaths in the UK during the coldest months of the year (December to March) than during the rest of the year. Two-thirds of these excess deaths are related to dangerously cold homes. An estimated 20% of the National Health Service clinical budget is spent on avoidable illness (such as cardiovascular and respiratory disease) caused or exacerbated by issues such as poor housing. Housing modifications to improve warmth and damp can help to improve population health. At present there are no data on the cost-effectiveness of improving the warmth of homes through housing modification. The Warm Homes for Health project is a collaboration between public health economists at Bangor University and UK housing providers Gentoo Green and Nottingham City Homes. The project will measure the effect of housing improvements on the health, quality of life, and wellbeing of residents in some of the most socioeconomically disadvantaged areas of the UK.Data will be collected from occupants of retrofitted homes. We will collect data at baseline before housing modification installation and then 6 and 12 months after installation. Outcome measures will include the EQ-5D (for health related quality of life) and the Short Warwick-Edinburgh Mental Well-being Scale. We will also collect individual health and social service use data. We will explore how a cost per quality-adjusted life year (QALY) for housing modification can be calculated for the purpose of comparing relative cost-effectiveness with medical interventions and the National Institute for Health and Care Excellence threshold of £20 000 to £30 000 per QALY. We will produce an incremental cost-effectiveness ratio to examine the incremental cost and quality of life effects of housing improvements. We will use independent t tests between individuals to test the hypothesis that different housing improvements have different effects on quality of life. If we require additional analysis of subgroups we will use one-way repeated measures and between-groups ANOVAs with ad-hoc comparisons. Sensitivity analyses will be used to test uncertainty.We aim to establish whether housing improvements are a cost-effective approach to improving population health. The project is currently ongoing, so there are no results to report.FundingThe Warm Homes for Health project is jointly funded by Gentoo Green and Nottingham City Homes. The funders are also represented on the research team and have provided input into the design of the study, recruitment, data collection, and follow-up. 相似文献
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Eight microsatellite markers were developed for African mole-rats using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol and pyrosequencing. The markers were developed in Bathyergus suillus and applied to a selection of individuals from seven related taxa: Bathyergus janetta, Cryptomys hottentotus hottentotus, C. h. pretoriae, Fukomys damarensis, F. darlingi, F. mechowii and Georychus capensis. The markers displayed low to moderate variation with allele numbers ranging between one and six per species. We propose that larger repeat numbers at di-, tri- and tetranucleotide repeat loci generally yield higher levels of polymorphism. 相似文献
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George A. Bray 《Journal of diabetes science and technology》2010,4(4):1003-1007
The worldwide consumption of sucrose, and thus fructose, has risen logarithmically since 1800. Many concerns about the health hazards of calorie-sweetened beverages, including soft drinks and fruit drinks and the fructose they provide, have been voiced over the past 10 years. These concerns are related to higher energy intake, risk of obesity, risk of diabetes, risk of cardiovascular disease, risk of gout in men, and risk of metabolic syndrome. Fructose appears to be responsible for most of the metabolic risks, including high production of lipids, increased thermogenesis, and higher blood pressure associated with sugar or high fructose corn syrup. Some claim that sugar is natural, but natural does not assure safety. 相似文献