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Mass spectrometry–based proteomics was employed to analyze urine from eight healthy volunteers during a 21-day bed rest (BR) study. The analysis included trypsinolysis in solution prior to liquid chromatography and tandem mass spectrometry (LC-MS/MS), and spectrum processing using the bioinformatic tools. Relying on 221 IPI indices with scores from 24 to 1700, 169 different proteins were identified. Molecular functions, biological processes, and cell components as the loci of certain protein functioning were determined with the help of UniProt-GOA. Associative interactions networks were constructed using BiNGO. There were 14 proteins identified that were functional in the cardiovascular system mostly. They were annotated, and the dynamics of their occurrence throughout the experiment was considered. Grounding on the biological functions of these proteins and an assumption of eligible activation of different biological processes during BR was made.  相似文献   
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The dehydrogenase activity of Escherichia coli BB cell extracts was studied at different growth stages in the presence of different substrates and triphenyl tetrazolium chloride as an electron acceptor. It was shown that the highest degree of reduction of triphenyl tetrazolium chloride was observed during exponential growth of the bacteria when potassium isocitrate was used as a substrate. It was found that extracts of the bacteria during the exponential phase of growth on an inert glassy carbon electrode in a three-electrode liquid electrochemical cell manifested electrochemical activity in the presence of potassium citrate and methylene blue or potassium hexacyanoferrate(III) as redox mediators.  相似文献   
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Oncolytic viruses are genetically engineered viruses that are designed to kill cancer cells while doing minimal damage to normal healthy tissue. After being injected into a tumor, they infect cancer cells, multiply inside them, and when a cancer cell is killed they move on to spread and infect other cancer cells. Chondroitinase ABC (Chase-ABC) is a bacterial enzyme that can remove a major glioma ECM component, chondroitin sulfate glycosoamino glycans from proteoglycans without any deleterious effects in vivo. It has been shown that Chase-ABC treatment is able to promote the spread of the viruses, increasing the efficacy of the viral treatment. In this paper we develop a mathematical model to investigate the effect of the Chase-ABC on the treatment of glioma by oncolytic viruses (OV). We show that the model''s predictions agree with experimental results for a spherical glioma. We then use the model to test various treatment options in the heterogeneous microenvironment of the brain. The model predicts that separate injections of OV, one into the center of the tumor and another outside the tumor will result in better outcome than if the total injection is outside the tumor. In particular, the injection of the ECM-degrading enzyme (Chase-ABC) on the periphery of the main tumor core need to be administered in an optimal strategy in order to infect and eradicate the infiltrating glioma cells outside the tumor core in addition to proliferative cells in the bulk of tumor core. The model also predicts that the size of tumor satellites and distance between the primary tumor and multifocal/satellite lesions may be an important factor for the efficacy of the viral therapy with Chase treatment.  相似文献   
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Many hospital-acquired purulent diseases and wound infections are due to multiresistant hospital strains of Staphylococcus aureus. The role of S. aureus nasal carriage in development of wound infections due to autoinfection is confirmed. Not only inpatients but also hospital staff can be highly colonized with coagulase positive staphylococci. The S. aureus persistence in hospital personnel results in distribution of the microorganisms in the environment. Therefore, detection of S. aureus carriers without signs of the infection among the hospital personnel and eradication of the pathogen make it possible to control outbreaks of S. aureus infection in hospitals. Clinical efficacy of nasal ointment of mupirocin in the treatment of S. aureus carriers among the intensive care personnel of the N. N.Blokhin Cancer Research Center was evaluated. S. aureus nasal carriage was diagnosed in 17 (26 per cent) out of 65 persons. All the isolates were susceptible to oxacillin. 5-7 days after discontinuation of the mupirocin nasal ointment use eradication of S. aureus was stated in 100 per cent of the cases. The effect was still observed in 94 per cent of the cases in 1 month, in 76 per cent of the cases in 5-6 months and in 60 per cent of the cases in 8-9 months. It is believed that mupirocin nasal ointment (Bactroban) is convenient to use, low toxic and highly active in the treatment of persons with S. aureus nasal carriage.  相似文献   
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Endogenous cardiotonic steroids (ECS) are putative ligands of the inhibitory binding site of the membrane sodium pump (Na+, K+-ATPase). There is growing evidence that cardiotonic steroids may promote the growth of cardiac and vascular myocytes, including evidence indicating growth stimulation at concentrations in the same range as circulating ECS concentrations. We investigated four parameters to determine whether ouabain, a proposed ECS, promotes growth of immortalized rat proximal tubule epithelial cells: cell count by hemocytometer; metabolic activity as reflected in the mitochondrial conversion of the tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, to its formazan product (MA); DNA synthesis reflected as bromodeoxyuridine incorporation (DNA); and mitosis reflected as histone phosphorylation state detected using anti-phosphohistone 3 antibody (HP). Maximum stimulatory responses were observed at 1 nm ouabain (MA, 20.3% increase, p < 0.01; DNA, 28.4% increase, p < 0.001; HP, maximum response at 0.5 h, 50% increase, p < 0.001). We observed that growth stimulation was associated with stimulation of ERK1/2 phosphorylation (ERK-P), and both growth and ERK-P could be blocked by the MEK inhibitor (U0126, 100 nm). Western blot analysis revealed that the only alpha isoform of Na+, K+-ATPase that could be detected in these cultures was the highly ouabain-resistant alpha1 isoform. Measurement of ouabain inhibition of ion transport in these cultures using 86Rb+ uptake revealed the predominance of the expected ouabain-resistant isoform (IC50 = 24 microm) and an additional minor ( approximately 15%) ouabain-sensitive inhibition with IC50 approximately 30 pm. Similar bimodal transport inhibition curves were obtained in freshly dissected rat proximal tubules. These results indicate that renal epithelial cells may be a sensitive target of the ERK1/2-activating and growth-promoting effects of ouabain even in the presence of ouabain-resistant Na+, K+-ATPase.  相似文献   
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The protoplasts of three Streptomyces species and their regenerative ability were studied using light microscopy. When Streptomyces lividans and S. erythraeus protoplasts are cultivated on regeneration media, their regeneration is not synchronous during the first day; some protoplasts revert to yield the mycelial form and also L-forms of these cultures are produced. If the protoplasts are transferred to a medium inducing L-forms, they grow and multiply for a long time with the production of L-form colonies. This process is maintained if S. lividans L-form cells are passaged on the medium inducing L-forms, but the protoplasts revert to yield the mycelial form on the regeneration medium.  相似文献   
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