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排序方式: 共有1301条查询结果,搜索用时 31 毫秒
91.
Gholap AR Toti KS Shirazi F Kumari R Bhat MK Deshpande MV Srinivasan KV 《Bioorganic & medicinal chemistry》2007,15(21):6705-6715
A series of 2-amino-5-oxo-4-phenyl-5,6,7,8-tetrahydroquinoline-3-carbonitrile and various analogues have been synthesized in excellent isolated yields starting from various arylidenemalononitrile and 3-amino-2-cyclohexen-1-one in 1-propanol as solvent at reflux temperature in the absence of any added catalyst. All the synthesized compounds were evaluated for their antifungal activity. The relationship between functional group variation and biological activity of the evaluated compounds is discussed in the article. 相似文献
92.
Manoj Kumar Vladimir León Angela De Sisto Materano Olaf A. Ilzins 《World journal of microbiology & biotechnology》2007,23(2):211-220
A Bacillus sp. strain DHT, isolated from oil-contaminated soil, grew and produced biosurfactant when cultured in variety of substrate
at salinities of up to 100 g l−1 and temperatures up to 45°C. It was capable of utilizing crude oil, fuels, various pure alkanes and PAHs as a sole carbon
and energy source across a wide range of temperature and salinity. Over the range evaluated, the degradation of hydrocarbon
and biosurfactant production was not influenced by salinity (0–10% wv−1) and temperature (30–45°C). The biosurfactant produced by the organism emulsified a range of hydrocarbons with hexadecane
as the best substrate and toluene as the poorest. From 16S rDNA analysis, strain DHT was related to Bacillus licheniformis. 相似文献
93.
Srivastava V Schinkel H Witzell J Hertzberg M Torp M Srivastava MK Karpinska B Melzer M Wingsle G 《The Plant journal : for cell and molecular biology》2007,49(1):135-148
Transgenic hybrid aspen (Populus tremula L. x P. tremuloides Michx.) plants expressing a high-isoelectric-point superoxide dismutase (hipI-SOD) gene in antisense orientation were generated to investigate its function. Immunolocalization studies showed the enzyme to be localized extracellularly, in the secondary cell wall of xylem vessels and phloem fibers. The antisense lines of hipI-SOD exhibited a distinct phenotype; growth rate was reduced, stems were thinner and leaves smaller than in wild-type (WT) plants. The abundance of hipI-SOD was reduced in the bark and xylem of plants from these antisense lines. The vascular tissue of transgenic lines became lignified earlier than in WT plants and also showed an increased accumulation of reactive oxygen species (ROS). Xylem fibers and vessels were shorter and thinner in the transgenic lines than in WT plants. The total phenolic content was enhanced in the antisense lines. Furthermore, microarray analysis indicated that several enzymes involved in cell signaling, lignin biosynthesis and stress responses were upregulated in apical vascular tissues of transgenic plants. The upregulation of selected genes involved in lignin biosynthesis was also verified by real-time PCR. The results suggest that, in the transgenic plants, a premature transition into maturation occurs and the process is discussed in terms of the effects of increased accumulation of ROS due to reduced expression of hipI-SOD during development and differentiation. 相似文献
94.
95.
Panchal M 《Bioinformatics (Oxford, England)》2007,23(4):509-510
ANeCA is a fully automated implementation of Nested Clade Phylogeographic Analysis. This was originally developed by Templeton and colleagues, and has been used to infer, from the pattern of gene sequence polymorphisms in a geographically structured population, the historical demographic processes that have shaped its evolution. Until now it has been necessary to perform large parts of the procedure manually. We provide a program that will take data in Nexus sequential format, and directly output a set of inferences. The software also includes TCS v1.18 and GeoDis v2.2 as part of automation. Availability: The software is available free of charge from http://www.rubic.rdg.ac.uk/~mahesh/software.html. The program is written in Java and requires the Java 1.4 Runtime Environment (or later) to run. The source code is included in the package, and includes the source from TCS and GeoDis. ANeCA, TCS and GeoDis are released under the GNU General Public License. 相似文献
96.
Gadd45alpha is shown to be induced by a wide spectrum of DNA-damaging agents and implicated in negative regulation of cell growth by causing G2-M arrest or induction of apoptosis. In the present study, we explored the involvement of p53 in the promoter activation of Gadd45alpha as well as the role of Gadd45alpha in carboplatin (Carb) or 5-fluorouracil (5-FU)-induced apoptosis in human papillomavirus virus (HPV)-positive HEp-2 and HeLa cells. We report that Carb or 5-FU upregulate Gadd45alpha and p53 in both these cells. Transient transfection of chloramphenicol acetyl transferase (CAT)-reporter construct driven by Gadd45alpha promoter clearly indicated that Gadd45alpha upregulation was mediated through activation of its promoter. Inhibition of p53 function by dominant-negative-p53 expression partially suppressed the activation of Gadd45alpha promoter. Further, the induction of apoptosis was assessed by detection of poly (ADP-ribose) polymerase (PARP) cleavage by Western blot analysis. Inhibition of upregulated Gadd45alpha expression by antisense expression vector did not modulate the Carb or 5-FU-induced apoptosis. Overall, we conclude that Gadd45alpha promoter activation partially depends on p53 function in HPV-positive cells. Moreover, Gadd45alpha protein does not modulate Carb or 5-FU-induced apoptosis in these cells. 相似文献
97.
Role of pro-oxidants and antioxidants in the anti-inflammatory and apoptotic effects of curcumin (diferuloylmethane) 总被引:3,自引:0,他引:3
Sandur SK Ichikawa H Pandey MK Kunnumakkara AB Sung B Sethi G Aggarwal BB 《Free radical biology & medicine》2007,43(4):568-580
Extensive research within the past half-century has indicated that curcumin (diferuloylmethane), a yellow pigment in curry powder, exhibits antioxidant, anti-inflammatory, and proapoptotic activities. We investigated whether the anti-inflammatory and proapoptotic activities assigned to curcumin are mediated through its prooxidant/antioxidant mechanism. We found that TNF-mediated NF-kappaB activation was inhibited by curcumin; and glutathione reversed the inhibition. Similarly, suppression of TNF-induced AKT activation by curcumin was also abrogated by glutathione. The reducing agent also counteracted the inhibitory effects of curcumin on TNF-induced NF-kappaB-regulated antiapoptotic (Bcl-2, Bcl-xL, IAP1), proliferative (cyclin D1), and proinflammatory (COX-2, iNOS, and MMP-9) gene products. The suppression of TNF-induced AP-1 activation by curcumin was also reversed by glutathione. Also, the direct proapoptotic effects of curcumin were inhibited by glutathione and potentiated by depletion of intracellular glutathione by buthionine sulfoximine. Moreover, curcumin induced the production of reactive oxygen species and modulated intracellular GSH levels. Quenchers of hydroxyl radicals, however, were ineffective in inhibiting curcumin-mediated NF-kappaB suppression. Further, N-acetylcysteine partially reversed the effect of curcumin. Based on these results we conclude that curcumin mediates its apoptotic and anti-inflammatory activities through modulation of the redox status of the cell. 相似文献
98.
Gene expression of rat alveolar type II cells during hyperoxia exposure and early recovery 总被引:1,自引:0,他引:1
Chen Z Chintagari NR Guo Y Bhaskaran M Chen J Gao L Jin N Weng T Liu L 《Free radical biology & medicine》2007,43(4):628-642
Alveolar epithelial cell (AEC) injury and repair during hyperoxia exposure and recovery have been investigated for decades, but the molecular mechanisms of these processes are not clear. To identify potentially important genes involved in lung injury and repair, we studied the gene expression profiles of isolated AEC II from control, 48-h hyperoxia-exposed (>95% O(2)), and 1-7 day recovering rats using a DNA microarray containing 10,000 genes. Fifty genes showed significant differential expression between two or more time points (P<0.05, fold change >2). These genes can be classified into 8 unique gene expression patterns. Real-time PCR verified 14 selected genes in three patterns related to hyperoxia exposure and early recovery. The change in the protein level for two of the selected genes, bmp-4 and retnla, paralleled that of the mRNA level. Many of these genes were found to be involved in cell proliferation and differentiation. In an in vitro AEC trans-differentiation culture model using AEC II isolated from control and 48-h hyperoxia-exposed rats, the expressions of the cell proliferation and differentiation genes identified above were consistent with their predicted roles in the trans-differentiation of AEC. These data indicate that a coordinated mechanism may control AEC differentiation during in vivo hyperoxia exposure and recovery as well as during in vitro AEC culture. 相似文献
99.