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Fourier transform infrared and Raman spectra of nebivolol have been recorded. The structure, conformational stability, geometry optimisation, and vibrational wave numbers have been investigated. Satisfactory vibrational assignments were made for the stable conformer of the molecule using Restricted Hartree–Fock (RHF) and density functional theory (DFT) calculation (B3LYP) with the 6-31G(d,p) basis set. Comparison of the observed fundamental vibrational wave numbers of the molecule and calculated results by RHF and DFT methods indicates that B3LYP is superior for molecular vibrational problems. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. The RHF and DFT-based NMR calculation procedure was also done. It was used to assign the 13C NMR chemical shift of nebivolol.  相似文献   
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CD44, an adhesion molecule, has been reported to be a binding site for Mycobacterium tuberculosis (M. tuberculosis) in macrophages and it also mediates mycobacterial phagocytosis, macrophage recruitment and protective immunity against pulmonary tuberculosis in vivo. However, the signalling pathways that are involved in M. tuberculosis–induced CD44 surface expression in monocytic cells are currently unknown. Exposure of THP-1 human monocytes to M. tuberculosis H37Rv and H37Ra induced distinct, time-dependent, phosphorylation of mitogen-activated protein kinase kinase-1, extracellular signal regulated kinase 1/2, mitogen-activated protein kinase kinase 3/6, p38 mitogen-activated protein kinase and c-jun N-terminal kinases. The strains also differed in their usage of CD14 and human leukocyte antigen-DR (HLA-DR) receptors in mediating mitogen-activated protein kinase activation. M. tuberculosis H37Rv strain induced lower CD44 surface expression and tumour necrosis factor-alpha levels, whereas H37Ra the reverse. Using highly specific inhibitors of mitogen-activated protein kinase kinase-1, p38 mitogen-activated protein kinase and c-jun N-terminal kinase, we report that inhibition of extracellular signal regulated kinase 1/2 and c-jun N-terminal kinases increases, but that inhibition of p38 mitogen-activated protein kinase decreases M. tuberculosis–induced CD44 surface expression in THP-1 human monocytes.  相似文献   
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The tannase production by Paecilomyces variotii was confirmed by high performance thin layer chromatography (HPTLC), and substrate specificity of the tannase was determined by zymogram analysis in sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS–PAGE). A clear band of activity observed after electrophoresis of culture filtrate in non-denaturing gels indicated the production of extracellular tannase by P. varoitii. HPTLC analysis revealed that gallic acid was the enzymatic degradation product of tannic acid during the fermentation process. The optimum condition for tannase production was at 72 h of incubation in shaking condition and addition of 1.5% tannic acid, 1% glucose and 0.2% sodium nitrate at temperature of 35°C and pH of 5–7. The production of extracellular tannase from Paecilomyces variotii was investigated under optimized conditions in solid-state fermentation (SSF), submerged fermentation (SmF) and liquid surface fermentation (LSF) processes. The maximum extracellular tannase production was obtained within 60 h of incubation under SSF followed by SmF and LSF.  相似文献   
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Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) from vertebrates, other than their predominant acylcholine hydrolase (esterase) activity, display a genuine aryl acylamidase activity (AAA) capable of hydrolyzing the synthetic substrate o-nitroacetanilide to o-nitroaniline. This AAA activity is strongly inhibited by classical cholinesterase (ChE) inhibitors. In the present study, benzalkonium chloride (BAC), a cationic detergent widely used as a preservative in pharmaceutical preparations, has been shown to distinctly modulate the esterase and AAA activities of BChEs. The detergent BAC was able to inhibit the esterase activity of human serum and horse serum BChEs and AChEs from electric eel and human erythrocyte. The remarkable property of BAC was its ability to profoundly activate the AAA activity of human serum and horse serum BChEs but not the AAA activity of AChEs. Thus BAC seem to preferentially activate the AAA activity of BChEs alone. Results of the study using the ChE active site-specific inhibitor diisopropyl phosphorofluoridate indicated that BAC binds to the active site of ChEs. Furthermore, studies using a structural homolog of BAC indicated that the alkyl group of BAC is essential not only for its interaction with ChEs but also for its distinct effect on the esterase and AAA activities of BChEs. This is the first report of a compound that inhibits the esterase activity, while simultaneously activating the AAA activity, of BChEs. Copyright 2000 Academic Press.  相似文献   
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Terminal drought is a major constraint to chickpea productivity. Two component traits responsible for reduction in yield under drought stress include reduction in seeds size and root length/root density. QTL‐seq approach, therefore, was used to identify candidate genomic regions for 100‐seed weight (100SDW) and total dry root weight to total plant dry weight ratio (RTR) under rainfed conditions. Genomewide SNP profiling of extreme phenotypic bulks from the ICC 4958 × ICC 1882 population identified two significant genomic regions, one on CaLG01 (1.08 Mb) and another on CaLG04 (2.7 Mb) linkage groups for 100SDW. Similarly, one significant genomic region on CaLG04 (1.10 Mb) was identified for RTR. Comprehensive analysis revealed four and five putative candidate genes associated with 100SDW and RTR, respectively. Subsequently, two genes (Ca_04364 and Ca_04607) for 100SDW and one gene (Ca_04586) for RTR were validated using CAPS/dCAPS markers. Identified candidate genomic regions and genes may be useful for molecular breeding for chickpea improvement.  相似文献   
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Wetlands Ecology and Management - Microplastic pollution in marine environments has increased rapidly during the last decades. These microplastic particles are transported into the coral...  相似文献   
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