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21.
S.P. Meenakshisundaram B. Karthikeyan K. Muthu S. Sebastian 《Molecular simulation》2013,39(7):584-595
The experimental and theoretical studies on the molecular structure and vibrational spectra of bis(thiourea)zinc(II) chloride (BTZC) crystals were investigated. The Fourier transform infrared, Fourier transform Raman and UV–vis spectra of BTZC were recorded. The molecular geometry and vibrational frequencies of BTZC in the ground state were calculated by using B3LYP with LANL2DZ as basis set. Comparison of the observed structural parameters of BTZC with single-crystal X-ray studies yields a good agreement. Vibrational analysis of the simultaneous IR and Raman activation of the Zn–Cl stretching mode in the molecule provides the evidence for the charge transfer interaction taking place within the molecule. The energy and oscillator strength are calculated by time-dependent density functional theory. The simulated spectra satisfactorily coincide with the experimental spectra. 相似文献
22.
Masayuki Sakakibara Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(5):1131-1137
The syntheses of three dl-demethylvariotins are described. 相似文献
23.
Michinori Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(1):52-58
Effects of materials extracted from potatoes with hot 80% ethanol on the course of phosphorylase reactions were examined. These materials had no effect on phosphorylase activities as determined by the rate of liberation of inorganic phosphate from glucose-1-phosphate in the presence of a large amount of primer; however, in the presence of a small amount of primer or in its absence, these materials had significant effects on the liberation of inorganic phosphate and starch formation. These results suggested the presence of a small amount of primers in these materials. Evidence was presented against the participation of d-enzyme on the formation of starch when partially purified preparations of potato phosphorylase or crude extracts from potatoes were used as the enzyme. 相似文献
24.
《MABS-AUSTIN》2013,5(4):1069-1083
Modification of antibody class and binding properties typically requires cloning of antibody genes, antibody library construction, phage or yeast display and recombinant antibody expression. Here, we describe an alternative “cloning-free” approach to generate antibodies with altered antigen-binding and heavy chain isotype by mimicking the germinal center reaction in antibody-secreting hybridoma cells. This was accomplished by lentiviral transduction and controllable expression of activation-induced cytidine deaminase (AID) to generate somatic hypermutation and class switch recombination in antibody genes coupled with high-throughput fluorescence-activated cell sorting (FACS) of hybridoma cells to detect altered antibody binding properties. Starting from a single established hybridoma clone, we isolated mutated antibodies that bind to a low-temperature structure of polyethylene glycol (PEG), a polymer widely used in nanotechnology, biotechnology and pharmaceuticals. FACS of AID-infected hybridoma cells also facilitated rapid identification of class switched variants of monoclonal IgM to monoclonal IgG. Mimicking the germinal center reaction in hybridoma cells may offer a general method to identify and isolate antibodies with altered binding properties and class-switched heavy chains without the need to carry out DNA library construction, antibody engineering and recombinant protein expression. 相似文献
25.
《Journal of receptor and signal transduction research》2013,33(1):37-40
AbstractInsulin plays an important role in various metabolic as well as anabolic actions in cells, including osteoblast cells. In the present study, we explored to determine if insulin receptor could associate with syndecan-1 in response to insulin and such association could lead to the activation of subsequent ERK I/II and alkaline phosphatase (ALP) in osteoblast cells. Insulin rapidly induces the association of insulin receptor with syndecan-1. Synstatin is a specific peptide inhibitor that blocks the binding of syndecan-1 to integrate. In the presence of synstatin, insulin-stimulated ERK I/II activation was dramatically inhibited, suggesting that syndecan-1/integrin interaction is essential in the activation of ERK I/II by insulin. Pretreatment of synstatin also inhibited the insulin-stimulated ALP activity. Taken together, these results suggest that insulin stimulates the association of insulin receptor with syndecan-1 and the complex formation of syndecan-1 and integrin could play an important role in ERK I/II–ALP signaling pathway in osteoblast cells. 相似文献
26.
《Journal of receptor and signal transduction research》2013,33(4):289-305
AbstractUrotensin‐II (U‐II) was identified as the natural ligand of the G protein‐coupled receptor GPR14, which has been correspondingly renamed Urotensin‐II receptor (U2R). The tissue distribution of U2R and the pharmacological effects of U‐II suggest a novel neurohormonal system with potent cardiovascular effects. We here report the human rhabdomyosarcoma cell line TE‐671 as the first natural and endogenous source of functional U2R in an immortalized cell line. In TE‐671 cells, U‐II stimulated extracellular signal regulated kinase phosphorylation and increased c‐fos mRNA expression. Furthermore, we demonstrate that the expression of U2R mRNA and functional U‐II high affinity binding sites are serum‐responsive and that they are specifically up‐regulated by interferon γ (IFNγ). We propose that IFNγ contributes to the previously observed increase of U2R density in the heart tissue of congestive heart failure (CHF) patients and we suggest that U2R up‐regulation, as a consequence of an inflammatory response, could lead to a clinical worsening of this disease. 相似文献
27.
Abstract A new species of Stipa, endemic to Sicily, named Stipa valdemonensis is described here. The new taxon is related to Stipa crassiculmis. Owing to the small number of individuals observed, in few restricted localities only, it is assigned the IUCN threat status “vulnerable”. 相似文献
28.
Ismet Basaran Selma Sinan Umit Cakir Mustafa Bulut Oktay Arslan Ozen Ozensoy 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):32-36
A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B. 相似文献
29.
Mirella Georgouli Cecilia Herraiz Eva Crosas-Molist Bruce Fanshawe Oscar Maiques Anna Perdrix Pahini Pandya Irene Rodriguez-Hernandez Kristina M. Ilieva Gaia Cantelli Panagiotis Karagiannis Silvia Mele Hoyin Lam Debra H. Josephs Xavier Matias-Guiu Rosa M. Marti Frank O. Nestle Jose L. Orgaz Victoria Sanz-Moreno 《Cell》2019,176(4):757-774.e23
30.