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It is shown that acute alcoholic intoxication causes essential changes of aldosterone content and balance of electrolytes in blood plasma of Wistar rat males. The SPL test revealed the inadequate reaction in the mineral-corticoid function of the adrenal glands in the rats with acute alcoholic intoxication. The method of the free choice of the load by the experimental rats is the most optimal way to assess. The rats with acute alcoholic intoxication displayed smaller tolerance to physical load.  相似文献   
75.
The patterns of formation of RNA nanoparticles (NPs) during thermal cycling of bacterial total tRNA in the presence of cations Ca2+, Mn2+, Ni2+, Zn2+, Co2+, and Cu2+ were studied. The optimal conditions for the production of NPs were found, and it was revealed that their size depends on the ratio of the concentrations of Me2+ and tRNA. The concentration of reagents for obtaining NPs of small size (from 5 to 100 nm) was selected. It was shown that tRNA-based nanoparticles can comprise short (20–50 nt) ribooligonucleotides, including aptamers and siRNAs. The stability of NPs during storage in buffer solutions of various composition was studied. It was found that the initial suspensions of NPs are quite stable, but they are rapidly destroyed in PBS buffer (pH 7.4). A simple and effective stabilizer (polyarginine) was found, the additives of which ensure the preservation of nanoparticles in PBS buffer for more than 5 h. Nanoparticles modified with the stabilizer are resistant to blood serum nucleases and can be used for transfection.  相似文献   
76.
Extremophiles - Spray drying is appropriate for the preservation of halophilic microorganisms due to the nature of these microorganisms, as they survive in adverse environmental conditions by being...  相似文献   
77.
Manipulation of the nutrient concentration is an inexpensive and efficient method for increasing lipid and TAG accumulation in algal cells. However, high volumetric production requires finding a proper balance between the decrease of biomass production and the increase in the total lipid content. We isolated a strain of green microalga Bracteacoccus bullatus and increased its lipid content from 17 to 59% of biomass dry weight by manipulating of nitrogen and phosphorus content in the medium. The 10-fold reduction of the nitrogen and phosphorus concentration in the medium was the most efficient method of the lipid induction compared to nutrient deplete and high nutrient conditions. The oleic (48–64% mass of total fatty acids) and linoleic (14–24% mass of total fatty acids) acids dominated in the fatty acid profile, thus making this strain a suitable candidate for biodiesel production.  相似文献   
78.
Laminins, the main components of basement membranes, are heterotrimers consisting of α, β, and γ polypeptide chains linked together by disulfide bonds. Laminins-1 and -2 are both composed of β1 and γ1 chains and differ from each other on their α chain, which is α1 and α2 for laminin-1 and -2, respectively. The present study shows that whereas laminins-1 and -2 are synthesized in the mouse developing lung and in epithelial–mesenchymal cocultures derived from it, epithelial and mesenchymal monocultures lose their ability to synthesize the laminin α1 chain. Synthesis of laminin α1 chain however returns upon re-establishment of epithelial–mesenchymal contact. Cell–cell contact is critical, since laminin α1 chain is not detected in monocultures exposed to coculture-conditioned medium or in epithelial–mesenchymal cocultures in which heterotypic cell–cell contact is prevented by an interposing filter. Immunohistochemical studies on cocultures treated with brefeldin A, an inhibitor of protein secretion, indicated both epithelial and mesenchymal cells synthesize laminin α1 chain upon heterotypic cell– cell contact. In a set of functional studies, embryonic lung explants were cultured in the presence of monoclonal antibodies to laminin α1, α2, and β/γ chains. Lung explants exposed to monoclonal antibodies to laminin α1 chain exhibited alterations in peribronchial cell shape and decreased smooth muscle development, as indicated by low levels of smooth muscle α actin and desmin. Taken together, our studies suggest that laminin α1 chain synthesis is regulated by epithelial–mesenchymal interaction and may play a role in airway smooth muscle development.  相似文献   
79.
The expression of laminin isoforms and laminin-binding integrin receptors known to occur in muscle was investigated during myogenic regeneration after crush injury. Comparisons were made between dystrophic 129ReJ dy/dy mice, which have reduced laminin α2 expression, and their normal littermates. The overall histological pattern of regeneration after crush injury was similar in dy/dy and control muscle, but proceeded faster in dy/dy mice. In vitro studies revealed a greater yield of mononuclear cells extracted from dy/dy muscle and a reduced proportion of desmin-positive cells upon in vitro cultivation, reflecting the presence of inflammatory cells and “preactivated” myoblasts due to ongoing regenerative processes within the endogenous dystrophic lesions. Laminin α1 was not detectable in skeletal muscle. Laminin α2 was present in basement membranes of mature myofibers and newly formed myotubes in control and dy/dy muscles, albeit weaker in dy/dy. Laminin α2-negative myogenic cells were detected in dy/dy and control muscle, suggesting the involvement of other laminin α chains in early myogenic differentiation, such as laminin α4 and α5 which were both transiently expressed in basement membranes of newly formed myotubes of dy/dy and control mice. Integrin β1 was expressed on endothelial cells, muscle fibers, and peripheral nerves in uninjured muscle and broadened after crush injury to the interstitium where it occurred on myogenic and nonmyogenic cells. Integrin α3 was not expressed in uninjured or regenerating muscle, while integrin α6 was expressed mainly on endothelial cells and peripheral nerves in uninjured muscle. Upon crush injury integrin α6 increased in the interstitium mainly on nonmyogenic cells, including infiltrating leukocytes, endothelial cells, and fibroblasts. In dy/dy muscle, integrin α6 occurred on some newly formed myotubes. Integrin α7 was expressed on muscle fibers at the myotendinous junction and showed weak and irregular expression on muscle fibers. After crush injury, integrin α7 expression extended to the newly formed myotubes and some myoblasts. However, many myoblasts and newly formed myotubes were integrin α7 negative. No marked difference was observed in integrin α7 expression between dy/dy and control muscle, either uninjured or after crush injury. Only laminin α4 and integrin α6 expression patterns were notably different between dy/dy and control muscle. Expression of both molecules was more extensive in dy/dy muscle, especially in the interstitium of regenerating areas and on newly formed myotubes. In view of the faster myogenic regeneration observed in dy/dy mice, the data suggest that laminin α4 and integrin α6 support myogenic regeneration. However, whether these accelerated myogenic effects are a direct consequence of the reduced laminin α2 expression in dy/dy mice, or an accentuation of the ongoing regenerative events in focal lesions in the muscle, requires further investigation.  相似文献   
80.
Nuclear bodies are relatively immobile organelles. Here, we investigated the mechanisms underlying their movement using experimentally induced interphase prenucleolar bodies (iPNBs). Most iPNBs demonstrated constrained diffusion, exhibiting infrequent fusions with other iPNBs and nucleoli. Fusion events were actin-independent and appeared to be the consequence of stochastic collisions between iPNBs. Most iPNBs were surrounded by condensed chromatin, while fusing iPNBs were usually found in a single heterochromatin-delimited compartment (“cage”). The experimentally induced over-condensation of chromatin significantly decreased the frequency of iPNB fusion. Thus, the data obtained indicate that the mobility of nuclear bodies is restricted by heterochromatin.  相似文献   
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