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541.
This study was undertaken to identify and characterize the globally expressed microRNAs (miRNAs) involved in interleukin-1β (IL-1β)-induced joint damage and to predict whether miRNAs can regulate the catabolic effects in osteoarthritis (OA) chondrocytes. Out of 1347 miRNAs analyzed by microarrays in IL-1β-stimulated OA chondrocytes, 35 miRNAs were down-regulated, 1 miRNA was up-regulated, and the expression of 1311 miRNAs remained unchanged. Bioinformatics analysis showed the key inflammatory mediators and key molecular pathways are targeted by differentially expressed miRNAs. Novel miRNAs identified could have important diagnostic and therapeutic potentials in the development of novel therapeutic strategies for pain managements in OA.  相似文献   
542.
Hepatitis C virus (HCV) is a major cause of chronic liver diseases including steatosis, cirrhosis and hepatocellular carcinoma. Currently, there is no vaccine available for prevention of HCV infection due to high degree of strain variation. The current treatment of care, Pegylated interferon α in combination with ribavirin is costly, has significant side effects and fails to cure about half of all infections. The development of in-vitro models such as HCV infection system, HCV sub-genomic replicon, HCV producing pseudoparticles (HCVpp) and infectious HCV virion provide an important tool to develop new antiviral drugs of different targets against HCV. These models also play an important role to study virus lifecycle such as virus entry, endocytosis, replication, release and HCV induced pathogenesis. This review summarizes the most important in-vitro models currently used to study future HCV research as well as drug design.  相似文献   
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544.
Zafar H. Zaidi 《CMAJ》1959,80(9):715-716
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545.
Bioactivity of immobilized cells, as evidenced by the production of intracellular phycoerythrin and extracellular polysaccharides by Porphyridium cruentum , in batch and repeated batch culture, respectively, is reported. Cells of P. cruentum immobilized within the vegetable sponge of Luffa cylindrica were grown in batch culture for 24 d and maintained at the stationary phase of growth in repeated batch cultures in a growth-limiting medium for 50 d. The study indicates the application potential of this recently reported biostructure as an immobilization matrix in microbial biotechnology.  相似文献   
546.

Globally, water resources contaminated with petroleum hydrocarbons are under much consideration due to their hazardous effects on human beings as well as on plants and animals in the ecosystem. Petroleum hydrocarbons are classified as recalcitrant pollutants in nature. These petroleum products are mostly released in the water resources during the petroleum refining process by oil refineries. The conventional clean-up technologies for hydrocarbons contaminated water have more destructive effects on the aquatic and land ecosystems. Consequently, to develop cost-effective and more environment-friendly techniques that clean up the environment and restore the marine ecosystem to its original forms. Keeping in view, this review article explores the detailed information on fabrication, cost-effectiveness, and an overview of innovation of the floating treatment wetlands (FTWs) using plants and bacterial combined functions to remediate the petroleum hydrocarbons contaminated water. The review also discusses the improvement of microbial efficacy for hydrocarbon degradation using FTWs. The review article shows the various applications of FTWs to remove different organic pollutants in petroleum hydrocarbons contaminated water. The review also describes the prospective benefits of FTWs for their multiple uses for removal of hydrocarbons, chemical oxygen demand (COD), biochemical oxygen demand (BOD), phenol, and solids from hydrocarbons contaminated water. This review widely discusses the role of hydrocarbons in degrading bacteria, and wetland plants and the mechanism involved during the remediation process of hydrocarbons in FTWs. It further demonstrates features disturbing the treatment efficiency of FTWs, and finally, it is concluded by successful applications of FTWs and various suggestions for potential future research prospects.

Graphical Abstract
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547.
The goal of this work was to produce high levels of endoglucanase in Escherichia coli for its potential usage in different industrial applications. Endoglucanase gene was amplified from genomic DNA of Bacillus subtilis JS2004 by PCR. The isolated putative endoglucanase gene consisted of an open reading frame of 1,701 nucleotides and encoded a protein of 567 amino acids with a molecular mass of 63-kDa. The gene was cloned into pET-28a(+) and expressed in E. coli BL21 (DE3). Optimum temperature and pH of the recombinant endoglucanase were 50 °C and 9, respectively which makes it very attractive for using in bio-bleaching and pulp industry. It had a K M of 1.76 μmol and V max 0.20 μmol/min with carboxymethylcellulose as substrate. The activity of recombinant endoglucanse was enhanced by Mg2+, Ca2+, isopropanol and Tween 20 and inhibited by Hg2+, Zn2+, Cu2+, Ni2+ and SDS. The activity of this recombinant endoglucanase was significantly higher than wild type. Therefore, this recombinant enzyme has potential for many industrial applications involving biomass conversions, due to characteristic of broad pH and higher temperature stability.  相似文献   
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549.
The E6-associated protein (E6-AP), although originally identified as a ubiquitin ligase, has recently been shown to function as a coactivator of steroid receptor-dependent gene expression in in vitro assays. In order to determine whether E6-AP acts as a coactivator in vivo, physiological parameters associated with male and female sex steroid action were assessed in the E6-AP null mouse. Gonadal size was reduced in E6-AP null male and female mice in comparison to wild-type controls in conjunction with reduced fertility in both genders. Consistent with this observation, defects in sperm production and function, as well as ovulation were observed. In comparison to wild-type controls, induction of prostate gland growth induced by testosterone and uterine growth by estradiol were significantly reduced. In contrast, estrogen and progesterone-stimulated growth of virgin mammary gland was not compromised by E6-AP ablation despite E6-AP expression in this tissue. This latter finding contrasts with the impaired estrogen and progesterone-induced mammary gland development observed previously for steroid receptor coactivator type 1 (SRC-1) and SRC-3 female knockout mice. Taken together, these results are consistent with a role for E6-AP in mediating a subset of steroid hormone actions in vivo. Nevertheless, differences observed between SRC and E6-AP knockout phenotypes indicate that these two families of steroid receptor coactivators are not functionally equivalent and supports the hypothesis that coactivators contribute to tissue-specific steroid hormone action.  相似文献   
550.
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