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101.
The influence of cucumarioside, triterpene glycoside obtained from Cucumaria japonica (Echinodermata, Holoturioidea), or sea cucumbers, on the resistance of mice to Bordetella pertussis infection (with the use experimental pertussis meningoencephalitis as a model) and on the development of immune response to corpuscular pertussis vaccine was studied. The preparation under test was shown to have greatly pronounced immunomodulating properties depending on both the concentration of cucumarioside and the route of its administration, as well as on the dose of pertussis vaccine. When administered orally in a dose of 4 micrograms per mouse and intraperitoneally in doses of 0.04 and 0.0004 micrograms, cucumarioside enhanced the protective effect of corpuscular pertussis vaccine. The use of cucumarioside in a dose of 0.001 micrograms per mouse abolished the suppressive action of large doses of pertussis vaccine in the background rosette-formation test at an early period after immunization and increased number of immune rosettes formed by lymphocytes in the spleen of mice immunized with different doses of the corpuscular vaccine.  相似文献   
102.
It was established in experiments on rats that intensity of "fast flash" of iron-induced chemiluminescence of biological samples containing microvolumes of blood plasma correlate with resistance of organism to severe hypoxia. The new method is promising for the estimation of the sensitivity of intact organism to severe hypoxia, for registration of antioxidant therapy effects and for studying the mechanisms of extreme factors influence on the organism.  相似文献   
103.
Estimation of heritability ha2 index in experiments on spontaneous and induced dominant lethality gives the possibility to evaluate with sufficient accuracy genetic determination of the effect and its dependence on casual reasons. Besides, the individual breeding method gave quite stable data both on late embryonic lethality index and on heritability value. Directed selection of different test-objects (species or stocks of Drosophila) should be carried out using heritability index, since selection efficiency mostly depends on this value degree. Making stocks resistant and sensitive to certain mutagen classes, their comparison from the point of view of their pharmacogenetic features, on the basis of the indices used, may be taken as the start of studies aimed at further identification of certain biochemical factors or system taking part in manifestation of mutagenic effect. The data obtained permit us to suggest an idea of advisability of studying the genetic control of mutagenesis in humans using the method described.  相似文献   
104.
Thymocytes stimulated in vitro in a mixed culture was sorbed by centrifugation on the surface of target cells for electron microscope study of cytology of immune T-lymphocytes and early cytolysis periods. A well developed Golgi apparatus was revealed in the cytoplasm of lymphocytes; there was also accumulation of tubular structures 50 to 60 nm in diameter which communicated with the cysterns of the granular endoplasmic reticulum, with "descended" vesiculi and plasmatic membrane of lymphocyte. This membrane formed numerous contacts with the membrane of target cells thus producing closed clefts. Taking into consideration these data and also current views on the intertransformation of membranes and intracellular transport a hypothetic scheme of the mechanism involved in the cytolysis of the target cell by immune T-lymphocyte was put forward.  相似文献   
105.
The method of recording the superweak chemifluorescence was applied to the study of the effect of tryptophan, 5-oxytryptophan, sertonin, histidine and histamine on the peroxication of lipids in the membranes of mitochondria of rat liver in the presence of Fe++ ions inducing this process. 5-oxytryptophan and serotonin inhibited this process in a concentration of 10(-5)-10(-4) M (protein content -1.8 mg per 1 ml of mitochondrial suspension). On the basis of studying the kinetics of the initial portion of the ascending branch of the "slow flare up" constants of the antioxidatinve activity (constituting 2.2-10(3) and 9.8-10(3) M-1 for 5-oxytryptophan and serotonin, respectively) was calculated. The antioxidative action is associated with the presence of the phenol group in the molecule of the compound under study. It is supposed that the action of 5-oxytryptophan and serotonin on peroxidation of lipids in the membranes was of significance for the regulation of permeability of the biological membranes, along with their effect on the other membrane processes.  相似文献   
106.
Fran?ois-Neetens fleck corneal dystrophy (CFD) is a rare, autosomal dominant corneal dystrophy characterized by numerous small white flecks scattered in all layers of the stroma. Linkage analysis localized CFD to a 24-cM (18-Mb) interval of chromosome 2q35 flanked by D2S2289 and D2S126 and containing PIP5K3. PIP5K3 is a member of the phosphoinositide 3-kinase family and regulates the sorting and traffic of peripheral endosomes that contain lysosomally directed fluid phase cargo, by controlling the morphogenesis and function of multivesicular bodies. Sequencing analysis disclosed missense, frameshift, and/or protein-truncating mutations in 8 of 10 families with CFD that were studied, including 2256delA, 2274delCT, 2709C-->T (R851X), 3120C-->T (Q988X), IVS19-1G-->C, 3246G-->T (E1030X), 3270C-->T (R1038X), and 3466A-->G (K1103R). The histological and clinical characteristics of patients with CFD are consistent with biochemical studies of PIP5K3 that indicate a role in endosomal sorting.  相似文献   
107.
The influence of the aminopeptide concentration on the growth of H. influenzae b culture and the synthesis of H. influenzae b capsular polysaccharide was determined. The maximum amount of capsular polysaccharide was accumulated at the concentration of aminopeptide in the culture fluid reaching 50 ml/l. An increase in the aminopeptide concentration led to a decreased amount of synthesized polysaccharide and an increased amount of biomass. The decrease of the aminopeptide concentration to 10 ml/l resulted in decreased amounts of both biomass and synthesized polysaccharide.  相似文献   
108.
In the process the cultivation of H. influenzae, type b, in semisynthetic nutrient medium with aminopeptide base the growth of the bacteria and the synthesis of capsular polysaccharide were shown to depend on the concentrations of aminopeptide, nicotinamide adenine nucleotide (NAD) and hemin. An increase in the concentrations of NAD and hemin stimulated the growth of H. influenzae and inhibited the synthesis of capsular polysaccharide. Similar effect was observed in the simultaneous increase of NAD and hemin concentrations. At elevated concentrations of NAD and hemin and the content of aminopeptide equal to 350 mI/l the maximum weight of biomass was achieved. The increase of hemin concentration had no influence on the growth of H. influenzae, type b, and the synthesis of capsular polysaccharide.  相似文献   
109.
Oxidation of pyruvate and palmitoylcarnitine in mitochondria is accompanied by the formation of acetyl-CoA, with its possible participation in the acetylation of various proteins and enzymes that may lead to the inhibition of their functions. This paper studies the effect of the excess of these substrates on respiration and induction of mitochondrial permeability transition pore (MPTP) in mitochondria and liver homogenates of healthy, obese, and type 2 diabetic (T2D) rats and mice. Both substrates produced a reversible inhibition of respiration and induced the opening of MPTP sensitive to cyclosporin A. Induction of MPTP in mitochondria was further activated by calcium ions and inhibited by the NO donor SNAP and NAD–a coenzyme and activator of deacetylation reactions. In obese and T2D animals, the opening of MPTP was stimulated by lower concentrations of L-palmitoylcarnitine than in healthy animals. In these pathologies, an activation effect on the MPTP induction was produced by ammonium ions, in the presence of which the concentration of L-palmitoylcarnitine required for the pore opening was reduced more than twofold. In liver homogenates, an added arginine reduced the probability of the MPTP formation. Analysis of mathematical models has shown that, due to the inhibition of pyruvate dehydrogenase kinase (PDK) by pyruvate, phosphorylation of pyruvate dehydrogenase (PDH) is strongly reduced, and this makes it possible to produce acetyl CoA in a wide range of pyruvate concentrations. The data obtained show that excess substrates that produce acetyl-CoA increase the probability of the MPTP opening, especially in pathologies associated with obesity and T2D. The ability of NO and NAD to inhibit MPTP indicates the participation of phosphorylation and acetylation/deacetylation reactions in this process.  相似文献   
110.
Ultrastructure of the fascicular zone in the cortex of the adrenals has been studied in untrained rats after a single physical loading (swimming with an additional load up to fatigue) and during restorative period (24, 48, 72 and 96 h of rest after the loading). The massive release of hormones during the prolonged physical work, as well as during the 1st and the 3d days of rest are estimated by ultrastructural changes in adrenocorticocytes. Signs of an increased permiability of the histohematic barrier in the gland are mostly manifested in 48 h after the loading: in the wall of the smallest vessels ruptures and discharge of formed elements of blood into the pericapillary space; numerous macrophages in the intercellular space phagocytaze the products of degeneration; residual bodies, fragments of decaying cells are seen in the blood capillary lumen. In 96 h of rest, in the fascicular zone of the adrenal cortex changes directed to restoration of the cholesterin depot are observed.  相似文献   
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