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71.
Natalia F. Avrova Tatyana V. Sokolova Yulia A. Vlasova Irina O. Zakharova Victor V. Furaev Maria P. Rychkova 《Neurochemical research》2010,35(1):85-98
GM1 ganglioside was found to increase the survival of PC12 cells exposed to H2O2, its action was blocked by Trk tyrosine kinase inhibitor K-252a. Thus, the inhibition of H2O2 cytotoxic action by GM1 constituted 52.8 ± 4.3%, but in the presence of 1.0 μM K-252a it was only 11.7 ± 10.8%, i.e. the
effect of GM1 became insignificant. Exposure to GM1 markedly reduced the increased accumulation of reactive oxygen species
(ROS) and diminished the inactivation of Na+,K+-ATPase induced in PC12 cells by H2O2, but in the presence of K-252a GM1 did not change these metabolic parameters. The inhibitors of extracellular signal-regulated
protein kinase, phosphatidyl inositol 3-kinase and protein kinase C decreased the effects of GM1. A combination of these protein
kinase inhibitors reduced inhibition of H2O2 cytotoxic action by GM1 to the larger extent than each of the inhibitors and practically abolished the ability of GM1 to
decrease H2O2-induced ROS accumulation. The protective and antioxidative effects of GM1 in PC12 cells exposed to H2O2 appear to be mediated by activation of Trk receptor tyrosine kinase and the protein kinases downstream from this enzyme. 相似文献
72.
73.
Semenova MV Sinitsyna OA Morozova VV Fedorova EA Gusakov AV Okunev ON Sokolova LM Koshelev AV Bubnova IuP Sinitsyn AP 《Prikladnaia biokhimiia i mikrobiologiia》2006,42(6):681-685
A new enzyme preparation of fungal pectin lyase (EC 4.2.2.10) was shown to be useful for the production of cranberry juice and clarification of apple juice in the food industry. A comparative study showed that the preparation of pectin lyase is competitive with commercial pectinase products. The molecular weight of homogeneous pectin lyase was 38 kDa. Properties of the homogeneous enzyme were studied. This enzyme was most efficient in removing highly esterified pectin. 相似文献
74.
The effects of 12 elements on the formation and accumulation of isoquinolines were studied in opium poppy seedlings (Papaver somniferum L.). Three types of concentration dependences of the effects of the elements under study were determined. The elements served as activators (Co, Mo, W, Cr, and Cu) or inhibitors of these processes (B, Fe, V, Mn, and Ca). The molecular mechanisms of action of these regulators are discussed. The optimum concentrations of Co and Mo were tested under combined treatment conditions with these elements. 相似文献
75.
Sokolova ES Liudyno VI Simbirtsev AS Klimenko VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2006,92(3):299-307
Behavioral effects of low, sub-pyrogenic doses of IL-lbeta were investigated in rats. It was shown that increasing of anxiety level started to occur as of the 5th day of the administration course. The data obtained suggest importance of pro-inflammatory cytokines in pathogenesis of psycho-emotional disorders. 相似文献
76.
A new microsporidium, Liebermannia patagonica n. gen., n. sp., is described from midgut and gastric caecum epithelial cells of Tristira magellanica, an apterous grasshopper species of southern Patagonia, Argentina. L.patagonica is diplokaryotic, apansporoblastic, homosporous, and polysporoblastic. Transitional (from merogony to sporogony) stages and sporonts of L. patagonica were surrounded by host rough endoplasmic reticulum. The ovocylindrical spores measured 2.9 +/- 0.09 x 1.2 +/- 0.04 microm (fresh, n = 50), and they had an isofilar polar filament of only three coils and a cluster of tubules instead of a classical posterior vacuole. Prevalence was high (up to 80.6%) at the type locality for the four years sampled . Maximum likelihood , neighbor joining, maximum parismony analyses of the small submit rDNA all placed L.patagonica(Accession No. DQ 239917) in one with Orthosomella operophterae. 相似文献
77.
Zhao W Weber C Zhang CL Romanek CS King GM Mills G Sokolova T Wiegel J 《Extremophiles : life under extreme conditions》2006,10(4):337-345
A novel thermophilic, alkali-tolerant, and CO-tolerant strain JW/WZ-YB58T was isolated from green mat samples obtained from the Zarvarzin II hot spring in the Uzon Caldera, Kamchatka (Far East Russia). Cells were Gram-type and Gram stain-positive, strictly aerobic, 0.7–0.8 μm in width and 5.5–12 μm in length and produced terminal spherical spores of 1.2–1.6 μm in diameter with the mother cell swelling around 2 μm in diameter (drumstick-type morphology). Cells grew optimally at pH25°C 8.2–8.4 and temperature 50–52°C and tolerated maximally 6% (w/v) NaCl. They were strict heterotrophs and could not use either CO or CO2 (both with or without H2) as sole carbon source, but tolerated up to 90% (v/v) CO in the headspace. The isolate grew on various complex substrates such as yeast extract, on carbohydrates, and organic acids, which included starch, d-galactose, d-mannose, glutamate, fumarate and acetate. Catalase reaction was negative. The membrane polar lipids were dominated by branched saturated fatty acids, which included iso-15:0 (24.5%), anteiso-15:0 (18.3%), iso-16:0 (9.9%), iso-17:0 (17.5%) and anteiso-17:0 (9.7%) as major constituents. The DNA G+C content of the strain is 45 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain JW/WZ-YB58T is distantly (<93% similarity) related to members of Bacillaceae. On the basis of 16S rRNA gene sequence, physiological and phenotypic characteristics, the isolate JW/WZ-YB58T (ATCC BAA-1258; DSM 17740) is proposed to be the type strain for the type species of the new taxa within the family Bacillaceae, Thermalkalibacillus uzoniensis gen. nov. sp. nov. The Genbank accession number for the 16S rRNA gene sequence is DQ221694.The Genbank accession number for the 16S rRNA gene sequence of strain JW/WZ-YB58T is DQ221694. 相似文献
78.
S. A. Borinskaya D. V. Rebrikov V. V. Nefedova I. A. Kofiadi M. V. Sokolova E. V. Kolchina E. A. Kulikova V. N. Chernyshov S. I. Kutsev A. V. Polonikov V. P. Ivanov A. I. Kozlov N. K. Yankovsky 《Molecular Biology》2006,40(6):931-935
Normally, the ability to digest milk sugar (lactose) is present in every child, but not in every adult. The decrease in lactase synthesis (hypolactasia) results in the inability to digest whole milk. Recent studies of the Finnish population have associated lactase persistence in adults with allele T of the C/T?13910 polymorphism located upstream of the lactase gene; a 100% correlation of primary hypolactasia with genotype C/C has been proved. In this study, the allele and genotype frequencies of C/T?13910 were determined in populations of Russia. The frequencies of genotype C/C, varying from 36.6% in Russians to 88.2% in Chukchi, were close to the published medical and epidemiological data on the hypolactasia frequencies in these populations. Genotyping was carried out by three different methods to determine the optimal one. Genotype C/C proved to be the key determinant of primary hypolactasia. It was assumed that DNA diagnosis of genotype C/C provides a predictive test to detect primary hypolactasia long before its clinical manifestation. 相似文献
79.
This review is dedicated to the structure and function of Golgi apparatus (GA). It summarizes contemporary data published in numerous experimental papers and in several reviews. Possible ways of intra-Golgi transport of proteins, existent models of structural and functional organization of Golgi organelle, as well as the issues of its biogenesis, posttranslational modification and sorting of proteins and lipids, and mechanisms of their traffic-king are discussed. Special attention is paid to the role of coatomer proteins (COPI, COPII and clathrin), fusion proteins (SNAREs), and small GTPases (ARF, SARI) in the secretory pathway. In addition, the phenomena of ultrastructural alterations of GA due to various functional conditions and physiological stimuli are specifically accented. We included in this review our original data on a probable involvement of GA in water transport, and on the organization of atypical GA in microsporidia--intracellular parasitic protists. 相似文献
80.