982 resultados para CYSTEINE PROTEASE INHIBITORS
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Ten dibenzofurans were synthesized and evaluated as human immunodeficiency virus (HIV)-1 inhibitors in vitro for the first time. Among these compounds, compounds 1, 6, 7 and 8 demonstrated significant anti-HIV-1 activity. Especially compound 1 showed the
Resumo:
Ten single benzyl phenyl ethers were synthesized and evaluated as human immunodeficiency virus-1 (HIV-1) inhibitors in vitro for the first time. Among these compounds, especially 4-nitrobenzyl phenyl ether (3h) exhibited the highest anti-HIV-1 activity wi
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To search for compounds with superior anti-human immunodeficiency virus type 1 (HIV-1) activity, ten 5,5'-(p-phenylenebisazo)-8-hydroxyquinoline sulfonates (4a-j) were synthesized and preliminarily evaluated as HIV-1 inhibitors in vitro for the first time. Some compounds demonstrated anti-HIV-1 activity, especially 5,5'-(p-phenylenebisazo)-8-hydroxyquinoline p-ethylbenzenesulfonate (4g) and 5,5'-(p-phenylenebisazo)-8-hydroxyquinoline p-chlorobenzenesulfonate (41) showed the more potent anti-HIV-1 activity with 50% effective concentration (EC50) values of 2.59 and 4.01 mu g/ml, and therapeutic index (TI) values of 31.77 and 24.51, respectively.
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Among the variety of applications for biosensors one of the exciting frontiers is to utilize those devices as post-synaptic sensing elements in chemical coupling between neurons and solid-state systems. The first necessary step to attain this challenge is to realize highly efficient detector for neurotransmitter acetylcholine (ACh). Herein, we demonstrate that the combination of floating gate configuration of ion-sensitive field effect transistor (ISFET) together with diluted covalent anchoring of enzyme acetylcholinesterase (AChE) onto device sensing area reveals a remarkable improvement of a four orders of magnitude in dose response to ACh. This high range sensitivity in addition to the benefits of peculiar microelectronic design show, that the presented hybrid provides a competent platform for assembly of artificial chemical synapse junction. Furthermore, our system exhibits clear response to eserine, a competitive inhibitor of AChE, and therefore it can be implemented as an effective sensor of pharmacological reagents, organophosphates, and nerve gases as well. © 2007 Materials Research Society.
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Multiple type I interferons (IFNs) have recently been identified in salmonids, containing two or four conserved cysteines. In this work, a novel two-cysteine containing (2C) IFN gene was identified in rainbow trout. This novel trout IFN gene (termed IFN5) formed a phylogenetic group that is distinct from the other three salmonid IFN groups sequenced to date and had a close evolutionary relationship with IFNs from advanced fish species. Our data demonstrate that two subgroups are apparent within each of the 2C and 4C type I IFNs, an evolutionary outcome possibly due to two rounds of genome duplication events that have occurred within teleosts. We have examined gene expression of the trout 2C type I IFN in cultured cells following stimulation with lipopolysaccharide, phytohaemagglutinin, polyI:C or recombinant IFN, or after transfection with polyI:C. The kinetics of gene expression was also studied after viral infection. Analysis of the regulatory elements in the IFN promoter region predicted several binding sites for key transcription factors that potentially play an important role in mediating IFN5 gene expression.
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Polybrominated diphenyl ethers (PBDEs) are used extensively as flame-retardants and are ubiquitous in the environment and in wildlife and human tissue. Recent studies have shown that PBDEs induce neurotoxic effects in vivo and apoptosis in vitro. However, the signaling mechanisms responsible for these events are still unclear. In this study, we investigated the action of a commercial mixture of PBDEs (pentabrominated diphenyl ether, DE-71) on a human neuroblastoma cell line, SK-N-SH. A cell viability test showed a dose-dependent increase in lactate dehydrogenase leakage and 3-(4,5-dimethylthia-zol-2-yl)-2,5-diphenyl-tetrazolium bromide reduction. Cell apoptosis was observed through morphological examination, and DNA degradation in the cell cycle and cell apoptosis were demonstrated using flow cytometry and DNA laddering. The formation of reactive oxygen species was not observed, but DE-71 was found to significantly induce caspase-3, -8, and -9 activity, which suggests that apoptosis is not induced by oxidative stress but via a caspase-dependent pathway. We further investigated the intracellular calcium ([Ca2+](i)) levels using flow cytometry and observed an increase in the intracellular Ca2+ concentration with a time-dependent trend. We also found that the N-methyl d-aspartate (NMDA) receptor antagonist MK801 (3 mu M) significantly reduced DE-71-induced cell apoptosis. The results of a Western blotting test demonstrated that DE-71 treatment increases the level of Bax translocation to the mitochondria in a dose-dependent fashion and stimulates the release of cytochrome c (Cyt c) from the mitochondria into the cytoplasm. Overall, our results indicate that DE-71 induces the apoptosis of ([Ca2+](i)) in SK-N-SH cells via Bax insertion, Cyt c release in the mitochondria, and the caspase activation pathway.
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In order to identify genes encoding the outer membrane proteins (OMPs) of the myxobacter Flavobacterium columnare G(4), the expression library of the bacterium was screened by using rabbit antisera developed against its OMPs. Positive colonies of Escherichia coli M15 containing fragments encoding the bacterial OMPs were selected for cloning the relevant genes by genomic walking methods. Two genes encoding a membrane-associated zinc metalloprotease and prolyl oligopeptidase are reported in this paper. The membrane-associated zinc metalloprotease gene (map) is 1800 bp in length, coding for 449 amino acids (aa). Despite the presence of a conserved motif HEXXH for all metalloproteases, the special HEXXH similar to 32 aa similar to E motif of the F. columnare G(4) Map and its low level of identity with other reported zinc-containing metalloproteases may imply that the membrane-associated zinc metalloprotease of F. columnare G(4) represents a new family of zincins. The gene encoding prolyl oligopeptidase (Pop), a serine proteinase, is 2352 bp in length, coding for 649 aa. Sequence homology analysis revealed that the Pop is also novel as it has <50% identity with other reported prolyl oligopeptidase family proteins. The present study represents the first to employ anti-fish bacterial OMP sera to screen genes of membrane-associated proteases of fish pathogenic bacteria, and to provide necessary information for the examination of the role of the two genes in the infection and pathogenesis of F. columnare.
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从采集的土壤样品中分离筛选出一株碱性蛋白酶产生菌G-41,经16S rRNA分子鉴定为芽孢杆菌属菌株。该菌株在发酵培养基中能产生较高产量的胞外碱性蛋白酶(1.7×104U/mL)。以G-41为出发菌株,对其进行重离子辐照诱变处理,获得突变株G-41-68,将该突变株再次经重离子诱变,从大量突变株中筛选出碱性蛋白酶高产菌株15Gy-54,其酶活力达到6.22×104U/mL。与出发菌株相比较,突变株G-41-68和15Gy-54的酶活力分别提高了1.58倍和2.65倍。对突变株15Gy-54的发酵条件进行了优化研究,结果表明,该菌株的碱性蛋白酶活力得到进一步提高,达到7.18×104U/mL,其最适发酵条件为:培养基(g/100mL)为胰蛋白胨1、酵母膏0.5、乳糖5、Na2HPO4·12H2O0.4、KH2PO40.03、Na2CO30.1、MgSO40.0481(4×10-3mol/L)、pH8.0,培养温度41℃,振荡培养时间42-48h。实验结果表明,重离子辐照诱变技术是一种非常有效的微生物诱变育种新技术。