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41.
The authors observed 68 drug addict in-patients, who received treatment for the pneumonia at the Primorski Regional Clinical Hospital and Vladivostok Municipal Clinical Hospital No. 1. The article details the specific features of the pneumonia of these in-patients. It was distinguished the 3 groups of hospital patients with the following characteristic features: patients with the respiratory distress syndrome of the adults; patients with the primary infective endocarditis mainly with the damage of respiratory (right) heart; patients with non-specific pneumonia. The peculiarities of the clinical process with the X-Ray pictures of the disease were also presented. The article identifies the acute beginning of the disease; the strongly pronounced intoxication syndrome; the usual cases of the late going to hospital of those patients; the extensiveness of the damage; the occurrence of the following complications at the early stage: pulmonary destruction, exudative pleurisy, empyema; the long period of the disease process; the development of the extensive pulmonary fibrosis. It was identified the 33.7% lethality for these groups of in-patients, while the average lethality of the in patients treated for pneumonia was 3.3% for the same period of time. The complicated pneumonia process of young patients with the infective endocarditis with damages of respiratory (right) hearts let us suppose their drug addiction.  相似文献   
42.
Redox regulation and carbohydrate recognition are potent molecular mechanisms which can contribute to platelet aggregation in response to various stimuli. The purpose of this study is to investigate the relationship between these mechanisms and to examine whether cell surface glycocalyx and cell stiffness of human platelets are sensitive to the redox potential formed by glutathione. To this end, human platelets were treated with different concentrations (0.05 μM to 6 mM) and ratios of reduced or oxidized glutathione (GSH or GSSG), and platelet morphological, mechanical, and functional properties were determined using conventional light microscopy, atomic force microscopy, and lectin-induced cell aggregation analysis. It was found that lowering the glutathione redox potential changed platelet morphology and increased platelet stiffness as well as modulated nonuniformly platelet aggregation in response to plant lectins with different carbohydrate-binding specificity including wheat germ agglutinin, Sambucus nigra agglutinin, and Canavalia ensiformis agglutinin. Extracellular redox potential and redox buffering capacity of the GSSG/2GSH couple were shown to control the availability of specific lectin-binding glycoligands on the cell surface, while the intracellular glutathione redox state affected the general functional ability of platelets to be aggregated independently of the type of lectins. Our data provide the first experimental evidence that glutathione as a redox molecule can affect the mechanical stiffness of human platelets and induce changes of the cell surface glycocalyx, which may represent a new mechanism of redox regulation of intercellular contacts.  相似文献   
43.
Adipose tissue-derived stem cells (ADSCs) are one population of adult stem cells that can self renew and differentiate into multiple lineages. Because of advantages in method and quantity of acquisition, ADSCs are gaining attention as an alternative source of bone marrow mesenchymal stem cells. In this study, we performed microRNA profiling of undifferentiated and of neurally-differentiated ADSCs to identify the responsible microRNAs in neurogenesis using this type of stem cell. MicroRNAs from four different donors were analysed by microarray. Compared to the undifferentiation control, we identified 39–101 microRNAs with more than two-fold higher expression and 3–9 microRNAs with two-fold lower expression. The identified microRNAs were further analysed in terms of gene ontology (GO) in relation with neurogenesis, based on their target mRNAs predicted by computational analysis. This study revealed the specific microRNAs involved in neurogenesis via microRNA microarray, and may provide the basic information for genetic induction of adult stem cell differentiation using microRNAs.  相似文献   
44.
We have previously demonstrated that incubation of V-79 cells in the medium containing the nitric oxide donor, NaNO2, increases cell resistance to damaging effect of gamma-rays, UV radiation and hyperthermia. In the present study, we investigated the effects of the nitric oxide donor on the sensitivity of V-79 cells to changes in osmomolarity of the medium by adding different amounts of sodium chloride or water. We found that pretreatment of the cells with NaNO2 resulted in a significant increase in the number of growing cells in 48 h after the treatment. The osmomolarity-dependent morphological changes in cultured cells were also substantially diminished following NaNO2 treatment. This effect could be observed under both hyper- and hypoosmosis, and was dependent on concentration of sodium chloride in hypertonic medium (being maximal under 0.17 M NaCl) and on the amount of water in hypotonic medium (being maximal under 1.1 times the dilution with water). In the experiments with increased osmomolarity, we found that the observed increase in the number of growing cells following NaNO2 treatment was accompanied with a significant increase of the mitotic index. These findings indicate that nitric oxide increases cell resistance to the damaging effects of osmotic shock in the way which is similar to the protective effect of these molecules against radiation and hyperthermia. Similarities in the effects of NaNO2 under different conditions leading to cell damage suggest that nitric oxide might serve as the universal factor participating in recovery of damaged cells and mediating increased cellular resistance to the damaging conditions.  相似文献   
45.
The global malaria situation, especially in Africa, and the problems frequently encountered in chemical control of vectors such as insecticide resistance, emphasize the urgency of research, development and implementation of new vector control technologies that are applicable at regional and local levels. The successful application of the sterile insect technique (SIT) for the control of the New World screwworm Cochliomyia hominivorax and several species of fruit flies has given impetus to the use of this method for suppression or elimination of malaria vectors in some areas of Africa including Northern State of Sudan. The research and development phase of the Northern State feasibility study has been started. Sudanese stakeholders are working side-by-side with the International Atomic Energy Agency in the activities of this important phase. Several ethical, legal and social issues associated with this approach arose during this phase of the project. They need to be seriously considered and handled with care. In this paper, these issues are described, and the current and proposed activities to overcome potential hurdles to ensure success of the project are listed.  相似文献   
46.
Bivalent lectins as bridging molecules between cells or cell surface lectins as docking points are involved in mediation of cell adhesion by specific recognition of suitable glycoconjugates on an opposing surface. The initial contact formation by a lectin can lead to intracellular post-binding events which effect stable cell association even in the presence of the haptenic sugar. To delineate the participation of intracellular signaling pathways in the cascade of reactions to establish firm association, reagents with proven inhibitory capacity on certain biochemical targets provide suitable tools. Using this approach with rat thymocytes and the galactoside-binding lectin from mistletoe (Viscum album L. agglutinin, VAA) as a model, a panel of 27 inhibitors with impact on e.g. several types of kinases, tyrosine phosphatases, NO synthases, G proteins, enzymes of arachidonate and cyclic nucleotide metabolism and calmodulin was systematically tested with respect to their capacity to impair the formation of lactose-resistant cell aggregates. In addition to the recently reported effectiveness of N-ethyimaleimide, nordihydroguaiaretic acid, and trifluoperazine the agents diacyigiycerol kinase inhibitor II, emodin, D609, DPI, KT5720, KT5926, MK-886, bisindolyimaleimide I, and (±)methoxyverapamil were able to reduce aggregate stability in the presence of the haptenic sugar. Thus, various types of kinases including p56 tyrosine kinase, lipoxygenases, phosphatidylcholine-specific phospholipase C as well as calmodulin and Ca2+-currents, but not modulators of the metabolism of cyclic nucleotides, NO synthases, MAP kinases, tyrosine phosphatases and phospholipase A (preferentially group II) and C can play a role in eliciting contact stability. More than one principal signaling pathway appears to be linked to the measurable parameter, since inhibitory substances show additive properties in co-incubation assays and differentially affect two lectin-elicited cellular activities, i.e. intracellular movement of Ca2+-ions and H2O2-generation, which can accompany cell adhesion and aggregation. Pronounced differences in the extent of modulation of H2O2-generation in human neutrophils by the same set of substances emphasizes that general conclusions on the post-binding effects for a certain lectin in different cell types are definitely precluded. In aggregate, the approach to employ inhibitors with target selectivity intimates an involvement of protein kinases A, C, Ca2+/calmodulin-dependent protein kinase II, p56 tyrosine kinase, leukotrienes and/or hydroxyeicosatetraenoic acids, phosphatidylcholine-specific phospholipase C and Ca2+-fluxes in events following initial binding of a galactoside-specific plant lectin to rat thymocytes which establish firm cell contacts.  相似文献   
47.
Molecular Biology Reports - The aim of this study was to elucidate the features of the expression of matrix metalloproteinases inducer—EMMPRIN (EMN) and matrix metalloproteinase 1 (MMP-1) in...  相似文献   
48.
49.
The glucose transport system of the extremely thermophilic anaerobic bacterium Thermotoga neapolitana was studied with the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DOG). T. neapolitana accumulated 2-DOG against a concentration gradient in an intracellular free sugar pool that was exchangeable with external source of energy, such as pyruvate, and was inhibited by arsenate and gramicidin D. There was no phosphoenolpyruvate-dependent phosphorylation of glucose, 2-DOG, or fructose by cell extracts or toluene-treated cells, indicating the absence of a phosphoenolpyruvate:sugar phosphotransferase system. These data indicate that D-glucose is taken up by T. neapolitana via an active transport system that is energized by an ion gradient generated by ATP, derived from substrate-level phosphorylation.  相似文献   
50.
Cone outer segments (OS) of the goldfish retina are diffusely labeled after intravitreal injection of [(3)H]fucose while rod OS remain unlabeled. By electron microscopic radioautography, the OS of red- and blue-sensitive cones are heavily labeled while green- sensitive cone OS are lightly labeled. The time-course and pattern of OS labeling in all cone types from 30 min to 24 h resemble that of incorporation of other sugars into rhodopsin in rod OS. The nature of the cone OS-specific fucosylated component(s) was examined using biochemical techniques. Cone OS were prelabeled by intravitreal injection of [(3)H]fucose 24 h before sacrifice. Photoreceptor OS were isolated using a discontinuous sucrose density gradient and it was verified by electron microscopic radioautography that the only source of radioactivity in the preparations was cone OS. The different cone types could be recognized by the heaviness of labeling, characteristic membrane spacing, and 'staining' of green cone OS in vitro with horseradish peroxidase. After acid hydrolysis of prelabeled photoreceptor membranes, 90 percent of the counts were in the neutral sugar fraction which was analyzed by thin-layer chromatography. Approximately 70 percent of the radioactivity co-chromatographed with authentic fucose. SDS-PAGE/fluorography of prelabeled photoreceptor membranes revealed a single radioactive component that was lightly stained with coomassie blue and showed an apparent molecular weight of 33,000. This cone-derived band was separated from unlabeled rod opsin which was well stained and showed an apparent mol wt of 38,000. Isoelectric focusing under denaturing conditions produced two major and one minor band of radioactivity with isoelectric points of 8.2, 8.6, and 8.8 respectively. No radioactivity was found in association with a stained band corresponding in isoelectric point to that of bovine opsin (pl, 6.2). The fucosylated component was readily digested by pronase, indicating its protein nature. Washing of the isolated OS with isotonic and hypotonic buffers failed to extract major amounts of the radioactivity, suggesting that the fucosylated component is an integral membrane protein. The presence of a fucosylated protein thus represents a major difference between cone and rod OS in the goldfish and has enabled us to identify cone OS in preparations of isolated photoreceptor membranes and to demonstrate the separation of a cone-derived glycoprotein from rod opsin.  相似文献   
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