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Induction of a cellular enzyme for energy metabolism by transforming domains of adenovirus E1a. 总被引:15,自引:2,他引:13
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R Kaddurah-Daouk J W Lillie G H Daouk M R Green R Kingston P Schimmel 《Molecular and cellular biology》1990,10(4):1476-1483
Brain creatine kinase is a major enzyme of cellular energy metabolism. It is overexpressed in a wide range of tumor cell lines and is used as a tumor marker. We reported recently that the promoter of the human gene has a strong sequence similarity to the adenovirus E2E promoter. This similarity suggested that the brain creatine kinase gene may be regulated by the viral activator E1a. Experiments reported here showed that both enzyme activity and mRNA levels were induced by the oncogenic products of the E1a region of adenovirus type 5, but unlike the viral E2E promoter, which is induced predominantly by E1a domain 3, brain creatine kinase induction required domains 1 and 2. These domains are important for transformation and for the association of E1a with the retinoblastoma gene product and other cellular proteins. The induction by an oncogene of a cellular gene for energy metabolism may be of significance for the metabolic events that take place after oncogenic activation. 相似文献
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Wilfredo Mellado Neal F. Magri David G.I. Kingston Renee Garcia-Arenas George A. Orr Susan Band Horwitz 《Biochemical and biophysical research communications》1984,124(2):329-336
Synthesis and biological activity of 2′-acetyltaxol and 7-acetyltaxol are reported. Activity is measured by cytotoxicity toward the macrophage-like cell line J774.2, and by promotion of microtubule assembly in the absence of exogenous GTP. Addition of an acetyl moiety at C-2′ results in loss of activity but not cytotoxicity. The properties of 7-acetyltaxol are similar to those of taxol in its effects on cell replication and on microtubule polymerization. Therefore a free hydroxyl group at C-7 is not required for activity and this position is available for structural modifications. 相似文献
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Sequences encoding two trypsin inhibitors occur in strikingly similar genomic environments. 总被引:1,自引:0,他引:1
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The nucleotide sequences of two approx. 4 kilobase pair segments of the bovine genome are presented. One segment contains a coding region for bovine pancreatic trypsin inhibitor (BPTI) and the other segment contains a coding region for a BPTI homologue. The two 4 kilobase pair sequences are strikingly similar over approx. 3.4 kilobase pairs of their sequence, including putative intron sequences, suggesting that they have evolved from a gene duplication event. 相似文献
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OBJECTIVES--To estimate the cost effectiveness of giving prophylactic antibiotics routinely to reduce the incidence of wound infection after caesarean section. DESIGN--Estimation of cost effectiveness was based, firstly, on a retrospective overview of 58 controlled trials and, secondly, on evidence about costs derived from data and observations of practice. SETTING--Trials included in the overview were from obstetric units in several different countries, including the United Kingdom. The costing study was based on data referring to the John Radcliffe Maternity Hospital, Oxford. SUBJECTS--A total of 7777 women were included in the 58 controlled trials comparing the effects of giving routine prophylactic antibiotics at caesarean section with either treatment with a placebo or no treatment. Cost estimates were based on data on 486 women who had caesarean sections between January and September 1987. MAIN OUTCOME MEASURE--Cost effectiveness of prophylaxis with antibiotics. RESULTS--The odds of wound infection are likely to be reduced by between about 50 and 70% by giving antibiotics routinely at caesarean section. Forty one (8.4%) women who had caesarean section were coded by the Oxford obstetric data system as having developed wound infection. The additional average cost of hospital postnatal care for women with wound infection (compared with women who had had caesarean section and no wound infection) was estimated to be 716 pounds; introducing routine prophylaxis with antibiotics would reduce average costs of postnatal care by between 1300 pounds and 3900/100 pounds caesarean sections (at 1988 prices), depending on the cost of the antibiotic used and its effectiveness. CONCLUSIONS--The results suggest that giving antibiotics routinely at caesarean section will not only reduce rates of infection after caesarean section but also reduce costs. 相似文献
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Kingston Janene K.; Geor Raymond J.; McCutcheon Laura Jill 《Journal of applied physiology》1997,83(4):1133-1143
Kingston, Janene K., Raymond J. Geor, and Laura JillMcCutcheon. Rate and composition of sweat fluid losses areunaltered by hypohydration during prolonged exercise in horses.J. Appl. Physiol. 83(4):1133-1143, 1997. Rate and ionic composition of sweat fluid losses and partitioning of evaporative heat loss into respiratory and cutaneous components were determined in six horses during three 15-km phases of exercise at ~40% of maximalO2 uptake. Pattern of change insweat rate (SR) and composition was similar during each phase. SRincreased rapidly for the first 20 min of exercise but remained at~24-28ml · m2 · min1during the remainder of each phase. Similarly, the concentrations of Naand Cl in sweat increased until 30 min of exercise but were unchangedthereafter. Sweat osmolality and concentrations of Na and Cl werepositively correlated with SR. Sweat K concentration decreased duringexercise but was not correlated with SR. Fluid losses were 33.8 ± 1.5 liters, resulting in decreases of ~21% in plasma volume and~11% in total body water. The ~6% hypohydration was notassociated with an alteration in SR, sweat composition, or heatstorage. Respiratory and cutaneous evaporative heat loss represented~23 and 70%, respectively, of the total heat dissipated, and thepartitioning of heat loss was similar in each exercise phase. Weconclude that SR and the relative proportions of respiratory andcutaneous evaporative heat loss are unchanged in horses during prolonged low-intensity exercise despite moderate hypohydration. 相似文献