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1.
By the acute glomerulonephritis (GN) of streptococcal etiology, autoantibodies (AA) reacting with the basal layer of skin epithelium (BLSE) are discovered. The presence of this AA's correlate with the high level of antibodies to the streptococcal group A polysaccharide (A-PS). In the control sera such AA's and the high level antibodies to A-PS are discovered very rarely. By the GN of non-streptococcal etiology, AA's to the BLSE apparently of other specificity are obtained in some cases, in spite of the absence of antibodies to A-PS. AA's reacting with the differentiated layers of skin epithelium are discovered in the high percent of cases by GN. The presence of these AA's do not correlate with the levels of antibodies to A-PS. The reduction of the number of T-lymphocyte suppressors is established in the blood by the presence of AA's to the BLSE by GN. This question is a subject of later investigations by the different autoimmune processes. Such data can apparently corroborate the previously expressed hypothesis, that AA's to BLSE, which as a rule react with endocrine thymus epithelium, are the cause of the beginning of immunoregulatory disorders, characteristic of autoimmune processes.  相似文献   
2.
Thanks to their strong immunostimulating properties and safety for humans, plant viruses represent an appropriate basis for the design of novel vaccines. The coat protein of Alternanthera mosaic virus can form virus-like particles that are stable under physiological conditions and have adjuvant properties. This work presents a recombinant human rotavirus A antigen based on the epitope of rotavirus structural protein VP6, using Alternanthera mosaic virus coat protein as a carrier. An expression vector containing the gene of Alternanthera mosaic virus (MU strain) coat protein fused to the epitope of rotavirus protein VP6 was designed. Immunoblot analysis showed that the chimeric protein was effectively recognized by commercial polyclonal antibodies to rotavirus and therefore is a suitable candidate for development of a vaccine prototype. Interaction of the chimeric recombinant protein with the native coat protein of Alternanthera mosaic virus and its RNA resulted in the formation of ribonucleoprotein complexes that were recognized by anti-rotavirus antibodies.  相似文献   
3.
A heterodimeric enzyme (gamma-glutamyltransferase) was studied in the reversed micellar medium of Aerosol OT (AOT) in octane. As was shown earlier, the size (radius) of inner cavity of the AOT-reversed micelles is determined by their hydration degree, i.e., [H2O]/[AOT] molar ratio, in the system. Owing to this, the dependence of hydrolytic, transpeptidation and autotranspeptidation activities of the enzyme on the hydration degree was investigated using L- and D-isomers of gamma-glutamyl(3-carboxy-4-nitro)anilide and glycylglycine as substrates. For all of the reaction types, the observed dependences are curves with three optima. The optima are found at the hydration degrees, [H2O]/[AOT] = 11, 17 and 26 when the inner cavity radii of reversed micelles are equal to the size of light (Mr 21,000) and heavy (Mr 54,000) subunits of gamma-glutamyltransferase, and to their dimer (Mr 75,000), respectively. Ultracentrifugation experiments showed that a change of the hydration degree resulted in a reversible dissociation of the enzyme to light and heavy subunits. The separation of light and heavy subunits of gamma-glutamyltransferase formed in reversed micelles was carried out and their catalytic properties were studied. The two subunits catalyze hydrolysis and transpeptidation reactions; autotranspeptidation reaction is detected only in the case of the heavy subunit. These findings imply that the reversed micelles of surfactants in organic solvents function as the matrices with adjustable size permitting to regulate the supramolecular structure and the catalytic activity of oligomeric enzymes.  相似文献   
4.
    
Microbiology - The composition and structure of the cell wall glycopolymers from Arthrobacter crystallopoietes VKM Ac-1107T (family Micrococcaceae, phylum Actinobacteria), previously assigned to...  相似文献   
5.
The cell wall of Spirilliplanes yamanashiensis VKM Ac-1993(T) contains four anionic polymers, viz., three teichoic acids and a sugar-1-phosphate polymer. The following are the structures of the teichoic acids: poly[-6-beta-D-glucopyranosyl-(1-->2)-glycerol phosphate] (PI), 1,3-poly(glycerol phosphate) bearing N-acetyl-alpha-D-glucosamine residues at O-2 (70%) (PII), and poly[-6-N-acetyl-alpha-D-glucosaminyl-(1-->2)-glycerol phosphate] (PIII). The repeating unit of the fourth polymer (PIV) has the structure of -6-alpha-D-GlcpNAc-(1-->6)-alpha-D-GlcpNAc-1-P- with a 3-O-methyl-alpha-D-mannopyranosyl residues at position 3 of some 6-phosphorylated N-acetylglucosamine residues (50%). Polymers PI, PIII and PIV have not hitherto been found in prokaryotic cell walls.  相似文献   
6.
Hybridization with cDNA arrays was used to obtain expression profiles of 214 protein-tyrosine kinase, protein-tyrosine phosphatase, dual-specific phosphatase, and other genes for kidney carcinomas (KC) and normal kidney tissues of 34 patients and for seven carcinoma cell lines. Computer analysis revealed three clusters of genes coexpressed in KC. A proliferating-cell gene cluster included MET, VIM, MYC, TOP2A, PCNA, etc. A neoangiogenesis and blood-cell gene cluster included LCK, HCK, FGR, MMP9, CSFR1, VEGF, FLT1, and KDR. A cluster corresponding to normal, differentiated kidney cells included ERBB2 (HER2) for receptor protein-tyrosine kinase, several phosphatase genes (PTPRE, PTPRB, DUSP9), and EGF. The results suggested that MET, DUSP9, PCNA, TOP2A, and VIM may serve as diagnostic and prognostic markers in KC. Tubulin and topoisomerase II were assumed to be promising targets for cell proliferation inhibitors in KC.  相似文献   
7.
Cell walls of three type strains of the Bacillus subtilis group, Bacillus mojavensis VKM B-2650, Bacillus amyloliquefaciens subsp. amyloliquefaciens VKM B-2582, and Bacillus sonorensis VKM B-2652, are characterized by the individual set of teichoic acids. All strains contained 1,3-poly(glycerol phosphates), unsubstituted, acylated with D-alanine, and glycosylated. The latter differ in the nature of the monosaccharide residue. Teichoic acids of B. mojavensis VKM B-2650T and B. amyloliquefaciens subsp. amyloliquefaciens VKM B-2582T contained α-glucopyranose, while those of B. sonorensis VKM B-2652T contained β-glucopyranose and N-acetyl-α-D-glucosamine. Moreover, cell walls of B. mojavensis VKM B-2650T contained a teichoic acid of poly(glycosylglycerol phosphate) nature with the following structure of the repeating unit: -4)-α-D-α-D-GlcpNAc-(1 → 3)]-Glcp-(1 → 2)-sn-Gro-(3-P-. The type strains have been characterized according to the composition of cell wall sugars and polyols. Application of teichoic acids (set and structure) as chemotaxonomic characteristics is discussed for six type strains of the Bacillus subtilis group. Polymer structures were determined by chemical and NMR spectroscopic techniques.  相似文献   
8.
The results are presented which confirm applicability of the Valsalva test as a functional exercise for the cardiovascular system while studying changes of the circulation regulation under high ambient pressure. Methods of transthoracic tetrapolar impedance plethysmography, electro- and intervalocardiography and mean arterial pressure measurement by means of the oscillometric servosystem are shown as adequate and highly informative under these conditions.  相似文献   
9.
Almost all of the investigated samples of the Arctic and Antarctic permafrost sediments of different genesis with ages from 5-10 thousand to 2-3 million years were found to contain viable micromycete and bacterial cells. The maximum amounts of viable cells of fungi (up to 10(4) CFU/g air-dried sample) and bacteria (up to 10(7)-10(9) CFU/g air-dried sample) were present in fine peaty sediment samples taken from different depths. The identified micromycetes belonged to more than 20 genera of the divisions Basidiomycota, Ascomycota, and Zygomycota, and some represented mitosporic fungi. Thawing the samples at 35 and 52 degrees C allowed the number of detected fungal genera to be increased by more than 30%. Aerobic heterotrophic prokaryotes were dominated by coryneform, nocardioform, and spore-forming microorganisms of the order Actinomycetales. Analysis of the isolated fungi and actinomycetes showed that most of them originated from the microbial communities of ancient terrestrial biocenoses.  相似文献   
10.
A colorimetric procedure to detect biotin bound to microtiter plates with a sensitivity down to 10(-16) mol was developed using biotinylated inorganic pyrophosphatase of Escherichia coli. Reaction of pyrophosphatase with 1 mM N-biotinyl-6-aminocaproic acid N-hydroxy-sulfonosuccinimide ester yielded a stable 87% active enzyme containing 5.6 mol biotin/mol. In the measurements of human immunoglobulin G, a biotinylated pyrophosphatase.streptavidin complex provided a sensitivity superior to that of conventional enzyme immunoassay due to low nonspecific binding. The new procedure was also more sensitive compared with that using biotinylated alkaline phosphatase. Together with high thermostability of pyrophosphatase and its substrate, low background staining allowed measurement of enzymatic activity to be performed at 60 degrees C for 4 h resulting in a marked increase in assay sensitivity.  相似文献   
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