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61.
Photodynamic inactivation of isolated crayfish neuron requires protein kinase C,PI 3-kinase and Ca2+
Bragin DE Kolosov MS Uzdensky AB 《Journal of photochemistry and photobiology. B, Biology》2003,70(2):99-105
Involvement of some signalling pathways in response to photodynamic therapy (PDT) of sulfonated aluminium phthalocyanine Photosens has been studied in isolated nerve cell. Neurone photosensitisation with 10(-7) M Photosens gradually inhibited firing and irreversibly abolished neuronal activity. Activation of protein kinase C (PKC) by phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) precipitated PDT-induced abolition of neurone activity and caused nucleus swelling and impairment of the nucleus border. Elevation of cytosolic Ca(2+) concentration by ionomycin or thapsigargin also reduced neurone lifetime. In contrast, the PKC inhibitors staurosporine, hypericin or chelerythrine as well as the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitors wortmannin or LY294002 increased neurone lifetime. These results showed that PKC, PI 3-kinase and Ca(2+) are involved in PDT-induced neurone inactivation and following death. 相似文献
62.
A glycosyl acceptor and a glycosyl donor having the N-3-deoxy-L-glycero-tetronic acid side chain already attached have been prepared and used for the synthesis of the di-through to the hexasaccharide that mimic the upsteam terminus of the O-specific polysaccharide of Vibrio cholerae O:1, serotype Inaba. The target tetra- and the hexasaccharide, which were obtained in the form of 5-methoxycarbonylpentyl glycosides, were linked to BSA using squaric acid diester chemistry. The conjugation reactions were monitored by surface enhanced laser desorption ionization-time of flight mass spectrometry (SELDI-TOF MS). This allowed the progression of the conjugation of the synthetic oligosaccharides in a controlled way and termination of the reaction when the desired molar hapten/BSA ratio had been reached, yielding neoglycoconjugates with predetermined carbohydrate/carrier ratios. The ability to monitor the conjugation by the SELDI-TOF MS technique made it possible to prepare, from one hapten in a one-pot reaction, several neoglycoconjugates having different, predetermined carbohydrate/carrier ratios. 相似文献
63.
The hydroperoxide anion cleaves unactivated amides and peptides although it is completely unreactive toward ethyl esters. The cleavage by HO2(-) proceeds faster than by OH(-) and involves additional routes with general acid assistance by H2O2 and general base assistance by OH(-) and HO2(-). Cleavage of polypeptides occurs at the N-terminal peptide bond. [reaction: see text] 相似文献
64.
Within the framework of a holographic dual model of QCD, we develop a formalism for calculating form factors of vector mesons. We show that the holographic bound states can be described not only in terms of eigenfunctions of the equation of motion, but also in terms of conjugate wave functions that are close analogues of quantum-mechanical bound state wave functions. We derive a generalized VMD representation for form factors, and find a very specific VMD pattern, in which form factors are essentially given by contributions due to the first two bound states in the Q2-channel. We calculate electric radius of the ρ-meson, finding the value . 相似文献
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66.
Natalia Sh. Lebedeva Anatoly I. Vyugin Natalia A. Pavlycheva Elena V. Parfenyuk Olga I. Davidova 《Thermochimica Acta》2002,390(1-2):179-186
The heats of interactions of zinc(II)tetraphenylporphyrine with 30 types of neutral molecules in benzene and carbon tetrachloride were measured using the calorimetric titration method. The thermodynamic characteristics of complex formation were calculated. The satisfactory multiparameter correlation of thermodynamic stability of the molecular complexes formed with physicochemical properties of the neutral molecules (electron pair donor ability, volume, electronic and orientational polarization) was obtained. 相似文献
67.
Anastasia S. Kozlenko Nadezhda I. Makarova Ilya V. Ozhogin Artem D. Pugachev Maria B. Lukyanova Irina A. Rostovtseva Gennady S. Borodkin Natalia V. Stankevich Anatoly V. Metelitsa Boris S. Lukyanov 《Mendeleev Communications》2021,31(3):403-406
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69.
The paper provides a combinatorial method to decide when the space of local systems with nonvanishing first cohomology on the complement to an arrangement of lines in a complex projective plane has as an irreducible component a subgroup of positive dimension. Partial classification of arrangements having such a component of positive dimension and a comparison theorem for cohomology of Orlik–Solomon algebra and cohomology of local systems are given. The methods are based on Vinberg–Kac classification of generalized Cartan matrices and study of pencils of algebraic curves defined by mentioned positive dimensional components. 相似文献
70.