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Biomedical subjects

A A Novikov

Publications and source records attributed to A A Novikov.

At least 37 records · Page 2Linked to original sources
PubMed2001

A novel method of gene transcript profiling in airway biopsy homogenates reveals increased expression of a Na+-K+-Cl- cotransporter (NKCC1) in asthmatic subjects.

Comprehensive and systematic analysis of airway gene expression represents a strategy for addressing the multiple, complex, and largely untested hypotheses that exist for disease mechanisms, including asthma. Here, we report a novel real-time PCR-based method specifically designed for quantification of multiple low-abundance transcripts using as little as 2.5 fg of total RNA per gene. This method of gene expression profiling has the same specificity and sensitivity as RT-PCR and a throughput level comparable to low-density DNA microarray hybridization. In this two-step method, multiplex RT-PCR is successfully combined with individual gene quantification via real-time PCR on generated cDNA product. Using this method, we measured the expression of 75 genes in bronchial biopsies from asthmatic versus healthy subjects and found expected increases in expression levels of Th2 cytokines and their receptors in asthma. Surprisingly, we also found increased gene expression of NKCC1--a Na+-K+-Cl- cotransporter. Using immunohistochemical method, we confirmed increased protein expression for NKCC1 in the asthmatic subject with restricted localization to goblet cells. These data validate the new transcriptional profiling method and implicate NKCC1 in the pathophysiology of mucus hypersecretion in asthma. Potential applications for this method include transcriptional profiling in limited numbers of laser captured cells and validation of DNA microarray data in clinical specimens.

Adult↗
PubMed1999

[Cardiolipin antibodies dependents on beta2-glycoprotein-1 in antiphospholipid syndrome].

AIM: To study beta2-GP-I-dependent binding of phospholipid antibodies (PAb) to phospholipids and this process participation in pathogenesis of antiphospholipid syndrome (APS). MATERIALS AND METHODS: IgG-fractions and sera from 20 patients with APS. Cofactor activity of beta2-GP-I isolated from serum of healthy donors was examined with modified immunoassay. RESULTS: Contrary to donor IgG, binding of IgG fractions isolated from sera of APS patients with cardiolipin grows dose-dependently in the presence of beta2-GP-I. Cofactor activity of beta2-GP-I is confirmed in the study of sera of APS patients. Sera containing beta2-GP-I-dependent antibodies to cardiolipin (aCL), unlike aCL-negative sera, react with solid-phase immobilized beta2-GP-I. CONCLUSION: It is confirmed that beta2-GP-I participates in interaction of PAb with cardiolipin. Pathogenetic implication of beta2-GP-I-dependent PAb for onset of APS is discussed.

Adult↗
PubMed1994

Cloning and expression of genes coding for carbohydrate degrading enzymes of Anaerocellum thermophilum in E.coli.

A gene library of Anaerocellum thermophilum Z-1320 was constructed in Escherichia coli using plasmid pUC18. Clones were selected by screening for hydrolysis of CMC, MU-Cel, lichenan and xylan. Recombinant clones expressing two beta-1,4-glucanases and two different xylanases were obtained. Both beta-1,4-glucanases were capable of degrading Avicel. Clones with xylanase activity also cleft PNPXyl, MU-Glu and MU-Cel. The genes of one beta-1,4-glucanase and one xylanase are probably located in the same region of A.thermophilum chromosome.

Carbohydrate Metabolism↗
PubMed1990

Bacillus amyloliquefaciens alpha-amylase signal sequence fused in frame with human proinsulin is properly processed by Bacillus subtilis cells.

The plasmid pBINS1, containing the promoter, SD and leader peptide sequences of Bacillus amyloliquefaciens alpha-amylase gene and 267 bp long sequence coding for human proinsulin directs the efficient synthesis of hybrid preproinsulin, as well as quantitative secretion of proinsulin outside of protease-deficient Bacillus subtilis AJ73 cells. The recombinant proinsulin has been isolated from the culture medium and its N-terminal sequence shown to be identical with that of natural human prohormone.

Amino Acid Sequence↗
PubMed1989

[The effect of synthetic proteinase inhibitors of the level of human recombinant proinsulin production, secreted by a genetically engineered strain of Bacillus subtilis].

Influence of O,O,-diethyl-1-(N-alpha-hydrohexafluoroisobutyryl)amino-1- methylpropylphosphonate and O,O-diisobutyl-1-[2-(ethoxycarbonyl)aminoperfluoroprop-2-yl] -1- methylpropylphosphonate on the level of production of human proinsulin secreted by a genetically engineered culture Bacillus subtilis AJ 73 (pBINS1.0.) has been studied. The above phosphonates, being non-toxic for microorganisms, reduced degradation of proinsulin by serine proteinases.

Animals↗
PubMed1988

[Hyposexuality in men with epilepsy].

Sexual disorders were studied in male epileptic patients. High hyposexuality rate was shown to be related with the early onset of the disease and localization of the epileptic focus in the temporal lobe. Putative links in the pathogenesis of sexual disorders in epileptic patients are described and the importance of their early detection stressed.

Adolescent↗
PubMed1987

[Isolation and analysis of human leukocyte interferons synthesized by bacterial producer strains].

Rapid and sensitive methods for immunochemical estimation of bacterially-made human leukocytic interferons were developed. A large number of strains producing such interferons was analyzed with these methods and optimal ones capable of synthesizing up to 10(10), 10(8), 10(9) and 10(9) IU/l of interferons alpha A, alpha N, alpha F and alpha I1 respectively were selected. The proteins were isolated in homogenous state and their main physico-chemical parameters were characterized. Interferon oligomers were detected. Their formation was partially due to intermolecular disulphide exchange. The effect on interferon alpha A of retinal (vitamin A) and its derivatives efficiently interacting with this protein was studied.

Bacteria↗
PubMed1987

[Design of a hybrid gene coding for the leader sequence of Bacillus amyloliquefaciens alpha-amylase and for human proinsulin].

The chemically synthesized structure gene of human proinsulin was cloned in E. coli on the secretory vector containing regulatory elements of the Bacillus amyloliquefaciens alpha-amylase gene. The proinsulin gene was inserted by the EcoRI site located immediately after the DNA area encoding the alpha-amylase signal peptide. The E. coli cells transformed by such a plasmid produced hybrid protein consisting of the alpha-amylase signal peptide, five amino acid residues after the gene mating and human proinsulin. For accurate mating of the alpha-amylase gene leader sequence and proinsulin gene directed mutagenesis was performed on the filiform phage M13 mp9 with synthetic oligonucleotide. The hybrid gene was transferred to the vector molecule capable of replicating in Bacillus subtilis. It was shown that in the cells of both E. coli and B. subtilis there is synthesized protein interacting by the radio-immunological data with antibodies to porcine insulin, a large portion of immunologically active protein being detected in the periplasmic space of E. coli cells and in the culture fluid of B. subtilis cells which was indicative of proinsulin secretion directed by the alpha-amilase regulatory elements.

Amino Acid Sequence↗
PubMedDate not supplied

[Factors controlling the biosynthesis of chlorosome antenna bacteriochlorophylls in green filamentous anoxygenic phototrophic bacteria of the family Oscillochloridaceae].

We determined the concentrations of bacteriochlorophylls (BChl) in the light-harvesting antennae of Oscillochloris trichoides (of the family Oscillochloridaceae belonging to green filamentous mesophilic bacteria) cultivated either with gabaculine, an inhibitor of the C-5 pathway of BChl biosynthesis in a number of bacteria, or at various illumination intensities. We determined the BChl c: BChl a molar ratios in intact cells, in chlorosome-membrane complexes, and in isolated chlorosomes. We revealed that BChl c synthesis in Osc. trichoides was more gabaculine-sensitive than BChl a synthesis. Accordingly, an increase in gabaculine concentrations in the medium resulted in a decrease in the BChl c: BChl a ratio in the tested samples. We suggest that BChl synthesis in Osc. trichoides proceeds via the C-5 pathway, similar to representatives of other families of green bacteria (Chlorobium limicola and Chloroflexus aurantiacus). We demonstrated that the BChl c: BChl a ratio in the chlorosomes varied from 55 : 1 to 110 : 1, depending on light intensity. This ratio is, therefore, closer to that of Chlorobiaceae, and it significantly exceeds the BChl c: BChl a ratio in Chloroflexaceae.

Bacterial Proteins↗