Biomedical subjects

V N Lazarev

Publications and source records attributed to V N Lazarev.

At least 19 recordsLinked to original sources

PubMed2006

Expression of Chlamydia trachomatis inclusion membrane protein genes IncB and IncC in Escherichia coli.

In this study, we have cloned the Chlamydia trachomatis genes incB and incC into the expression plasmid vectors from pET series for the subsequent isolation of recombinant proteins. As a result, we have obtained the first full-length recombinant C. trachomatis proteins IncB and IncC, which can be used for following antibody production and for study of their protein-protein interaction.

Amino Acid Sequence↗

PubMed2005

Effect of induced expression of an antimicrobial peptide melittin on Chlamydia trachomatis and Mycoplasma hominis infections in vivo.

A plasmid construct was designed in which the gene of antimicrobial peptide melittin is controlled by the tetracycline-responsive promoter of human cytomegalovirus, aided by a constitutively expressed trans-activator protein gene. Its vaginal administration and induction of melittin gene transcription with doxycycline markedly suppressed subsequent genital tract infection of mice by Mycoplasma hominis and Chlamydia trachomatis. At least half of the melittin-protected animals proved free of either pathogen within 3-4 weeks. Recombinant plasmids expressing genes of antimicrobial peptides hold much promise as agents for prevention and control of urogenital latent infections.

Animals↗

PubMed2005

Location of C. trachomatis Inc proteins during expression of their genes in HeLa cell culture.

Plasma constructions including genes encoding C. trachomatis inclusion membrane protein as composite proteins with reporter green fluorescent protein were obtained. After transfection of HeLa cell culture with the resultant plasmid constructions the location of inclusion membrane proteins in transfected cell was for the first time detected by confocal microscopy.

Bacterial Proteins↗

PubMed2005

Identification of serovar-specific single-nucleotide polymorphisms of C. Trachomatis omp1 gene.

Complete sequences of omp1 gene encoding chlamydial main outer membrane protein were analyzed in 76 clinical strains of C. trachomatis. Thirty-four serovar-specific single-nucleotide polymorphisms were identified, 20 of them meet two criteria: unique position of the nucleotide and unique nucleotide substitution. Evaluation of serovar-specific single-nucleotide polymorphisms of omp1 gene can appreciably simplify and accelerate genetic diagnosis of C. trachomatis serovars.

Chlamydia trachomatis↗

PubMed2004

Experimental Mycoplasma hominis infection of the genital tract in BALB/c mice.

We studied the ability of laboratory and clinical strains of Mycoplasma hominis to colonize the genital tract mucosa in BALB/c mice. Colonization with mycoplasma occurred only in mice receiving estrogen. Mycoplasma hominis strains obtained after 3-fold passage through the vaginal mucosa in mice and administered intravaginally in a dose of 0.5 x 10(8) CFU/ml caused infection in 100% animals. Inflammation in the lower genital tract was reduced by the 8th week after infection.

Animals↗

PubMed2004

Structural organization of the genome of SARS-associated coronavirus (Strain SoD) isolated on the territory of the Russian Federation.

Complete nucleotide cDNA sequence (29715 nucleotides) of SARS-associated coronavirus (strain SoD) isolated for the first time in the territory of the Russian Federation was determined. Phylogenetic analysis revealed maximum similarity between strain SoD genome and Frankfurt 1 strain genome. Three nucleotide substitutions determining two amino acid substitutions were detected.

Amino Acid Substitution↗

PubMed2004

Mutations in a 23S rRNA gene of Chlamydia trachomatis associated with resistance to macrolides.

For six clinical isolates of Chlamydia trachomatis, in vitro susceptibility to erythromycin, azithromycin, and josamycin has been determined. Four isolates were resistant to all the antibiotics and had the mutations A2058C and T2611C (Escherichia coli numbering) in the 23S rRNA gene. All the isolates had mixed populations of bacteria that did and did not carry 23S rRNA gene mutations.

Anti-Bacterial Agents↗

PubMed2004

[Analysis of point mutations in the ygeD, gyrA and parC genes in fluoroquinolones resistant clinical isolates of Chlamydia trachomatis].

Resistance of 14 clinical isolates of C. trachomatis to fluoroquinolones, i.e. of ciprofloxacin, pefloxaxin and ofloxacin, was assayed. Three isolates with a high resistance degree to all 3 drugs (MIC equal or above 64 microg/ml) were detected. MIC was found to be equal to or below 4 microg/ml for 3 isolates. The remaining isolates had an intermediate resistance level. The nucleotide sequence was established for the Quinolone-Resistance Determining Region (QRDR) genes coding the DNA-gyrase subunit A (gyrA) and DNA-topoisomerase IV subunit C (parC) as well as for the 3'-region of ygeD coding, presumably, the efflux protein. In none of the isolates, the gyrA and gyrC QRDR differed from the corresponding regions in the published C. trachomatis genome sequence. Several silent mutations and mutations resulting in amino acid substitutions were observed in the ygeD 3' region of 2 isolates resistant to high FQ concentrations and in 1 isolate with the intermediate resistance level.

Anti-Bacterial Agents↗

PubMed2004

[Structural-functional motifs of sterol 14-alpha demethylases (CYP51)].

CYP51 family of cytochromes P450 (sterol 14-alpha-demethylases) comprises the representatives from different kingdoms of living world, thus positioning itself as the most ancient member of the superfamily. In the course of the present research the collection of 36 full-length CYP51 amino acid sequences was submitted to cluster analysis. Each node of the clustering dendrogram corresponds to the groups of proteins, located on the branches descending from the node. By making the multiple alignment of each group of protein sequences we obtained the node-specific consensus sequences. The informational content of the consensus was defined as the presence of the compact conserved sites, the motifs. The assessment of informational content was computed using Sherman's non-parametric statistical criterion. The high informational content was observed for the 100% conserved consensus sequences of the following CYP51,s groups: fungi, animal+plant, plant+protista and bacteria. These selected consensus sequences were next aligned all together to get the final consensus for the whole family. To enrich the informational content of the CYP51 consensus the level of its conservation was dropped to 75%. Regions of statistically significant conservation were unraveled in the CYP51 consensus sequence. These regions (motifs) were then correlated with the information on secondary structure elements and substrate recognition sites reported for CYP51 from Mycobacterium tuberculosis. Seven motifs appeared to be obligatory for every CYP51 protein. The motifs thus obtained were searched for among all the known cytochrome P450 proteins. Some motifs were found to be absolutely specific for 14-alpha-demethylases, whereas others were common to different species of cytochromes P450.

Amino Acid Motifs↗

PubMed2003

[Cloning and expression of the Mycoplasma hominis ftsZ for a cell division protein].

A Mycoplasma hominis chromosomal fragment containing the full-length ftsZ gene was cloned and sequenced. Natural expression of this gene was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) with total RNA. The M. hominis FtsZ protein was shown to differ substantially from its counterparts of two other Mycoplasma species, M. genitalium and M. pneumoniae. The possibility of M. hominis ftsZ expression in Escherichia coli was demonstrated with several bacterial strains. The M. hominis FtsZ protein was isolated from E. coli cells transformed with recombinant plasmids carrying the M. hominis ftsZ gene. Complementation between the E. coli and M. hominis FtsZ proteins was observed in transformants.

Amino Acid Sequence↗

PubMed2003

[Sparing conservative surgery in children with chronic purulent otitis media].

A novel method of treatment of otitis media purulenta chronica in children implies administration of donor (from the parents or donor with the same blood group) plasm possessing a complete set of humoral and cellular immunity components. As a monotherapy, plasm treatment proved highly effective both before surgery and after it.

Adolescent↗

PubMed2002

Induced expression of melittin, an antimicrobial peptide, inhibits infection by Chlamydia trachomatis and Mycoplasma hominis in a HeLa cell line.

As the number of pathogenic microbial strains resistant to different antibiotics increases, amphipathic peptides with antimicrobial activity are promising agents for the therapy of infectious diseases. This work deals with the effect of an amphipathic antimicrobial peptide, melittin, expressed within recombinant plasmid vectors, on infection with urogenital pathogens Chlamydia trachomatis and Mycoplasma hominis in HeLa cell culture. Recombinant plasmid constructs with the melittin gene under the control of the tetracycline-responsive promoter of human cytomegalovirus were obtained. We showed inhibition of C. trachomatis and M. hominis infection after the introduction of recombinant plasmid vectors expressing the melittin gene into the infected cell culture.

Chlamydia trachomatis↗

PubMed2002

Evaluation of antibiotic sensitivity of Chlamydia trachomatis using RT-PCR.

The sensitivity of 11 clinical strains of Chlamydia trachomatis to azithromycin, ofloxacin, doxycycline, and erythromycin was evaluated. The minimum inhibiting concentrations of all antibiotics for 90% strains, determined by PCR with reverse transcription of omp3B gene RNA (GenBank U68443) corresponded to, and those with reverse transcription of 16S rRNA gene RNA (GenBank X54451) far surpassed the minimum bactericidal concentrations for 90% strains determined by direct immunofluorescence with monoclonal antibodies to the major outer membrane protein.

Base Sequence↗

PubMed2002

[Characteristics of autonomic dystonia in children with vasomotor rhinitis].

Data obtained at analysis of tables of screening diagnosis, cardiointervalograms, tilt tests used in examination of 57 children with neurovegetative vasomotor rhinitis point to disorders in the autonomic nervous system (by initial vegetative tone), vegetative reactivity. Parasympathetic prevalence in the initial vegetative tone and cardiointervalograms stems from sympathetic hypoactivity in the majority of the patients. The above vegetative shifts dictate the necessity of vegetotropic medication inclusion into combined therapy of vasomotor rhinitis.

Adolescent↗

PubMed2000

[Infectious complications in electric cardiac stimulation].

There were 4424 patients operated for alterations of the cardiac rhythm. Primary electrocardiostimulation was performed in 3183 of them, reoperations in 1241 patients (39%). Infectious complications took place in 146 patients (3.3%). Based on their experiences the authors developed the strategy of treatment of patients with purulent complications and sepsis depending on their character and time of their appearance.

Adolescent↗

PubMed2000

[The specific features of the functional status of the pituitary- adrenal and sympatho-adrenal system in children with angiofibromas of the skull base].

Analyzing the results of examination of 14 boys aged 6 to 13 years who had angiofibromas of the skull base has led to the conclusion that the disease runs in the presence of the markedly activated sympathoadrenal and pituitary-adrenal systems and lipid oxidation products. While choosing a therapy, it is necessary to take into account hormonally metabolic and antioxidative imbalance and to prescribe metabolic and membrane-stabilizing drugs.

Adolescent↗

PubMed1999

Inhibition of influenza A virus reproduction by a ribozyme targeted against PB1 mRNA.

A ribozyme gene directed at a specific cleavage of mRNA coding for PB1 protein, a component of RNA-dependent RNA-polymerase of influenza A virus, was constructed. The avian adenovirus CELO virus-associated RNA (VA RNA CELO) promoter and human cytomegalovirus (CMV) promoter were used for the permanent expression of the ribozyme in cell lines. The cells were infected with influenza A virus strains A/Singapore/1/57 and A/WSN/33, and the suppression of the virus reproduction and virus-specific protein synthesis was measured. The maximal level of the inhibition of virus reproduction as compared to the reproduction in non-transformed cells was 93.5%. Defective recombinant adenoviruses were constructed carrying the genes of functional and non-functional ribozymes under the control of human cytomegalovirus (CMV) promoter. The reproduction of A/WSN/33 virus in CV-1 cells preinfected with recombinant adenoviruses was shown to be suppressed.

Adenoviridae↗

PubMed1998

[The status of autonomic nervous system in children with chronic sinusitis].

Such parameters of autonomic nervous system as initial vegetative tonicity, vegetative reactivity, vegetative support of activity were for the first time assessed in children with chronic sinusitis. The vegetative dysfunction was found in purulent and purulent-polypous sinusitis. The above vegetative unbalance dictates the necessity of addition of various vegetotropic modalities to combined treatment of chronic sinusitis.

Autonomic Nervous System Diseases↗