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A A Nikonova

Publications and source records attributed to A A Nikonova.

10 recordsLinked to original sources
PubMed2003

[Molecular genetic characteristics of rifampicin-resistant Mycobacterium tuberculosis isolates in Novosibirsk].

Forty rifampicin-resistant clinical isolates from patients living in Novosibirsk were studied. Six alleles earlier described in the literature were identified by the sequencing technique. The frequency of mutations in the studied samples slightly differs from that earlier reported for other geographic regions: 21 (52.5%) strains carried the mutated codon TTG in position 531 (Ser-->Leu), 7 (17.5%) had GTC in position 516 (Asp-->Val) and 2 (5%) had the GAC substitution in position 526 (His-->Asp), which is prevalent elsewhere. Sequence analysis revealed no mitations in 5 (12.5%) of the 40 isolates although this isolate was repeatedly resistant to rifampicin. VNTR-typing targeted to tandem repeats (ETR A, B, C, D, and E) was carried out to establish a genetic relationship for rifampicin-resistant isolates. Nine genetic types with VNTR-profiles termed as 12322, 32122, 32123, 32124, 32125, 32522, 23524, 12223, 22222, 33433 were revealed. There was no strict correlation between the type of mutation in the rpoB gene and the VNTR-type, which reflects different rates of evolution and the level of selective pressure on these genetic targets. The isolates of VNTR-types 32123 and 32125 with mutations in codon 531, and type 32122 in codons 531, 526, 516 showed a high clustering. This is likely to reflect the recent transmission and clonal dissemination of the epidemic strains of Mycobacterium tuberculosis. Thus, mutations in the rpoB gene did not reduce the virulence and transmissivity of these clones. Twenty-six of 27 clinical isolates selected by rifampicin-resistance were also resistant to isoniazid, which confirms the known fact that rifampicin-resistance may be used as a marker of isoniazid-resistance.

Antitubercular Agents↗
PubMed2002

[Differential diagnostic criteria of lateral amyotrophic sclerosis].

Differential diagnostic criteria of lateral amyotrophic sclerosis (LAS) and lateral amyotrophic sclerosis syndrome were elaborated on the basis of complex investigation, including EMG and blood plasma trace element analysis. Fifty-two patients (25 with LAS, 27 with LAS syndrome) have been examined, the diagnoses being established according to the World Neurologist Federation criteria. LAS syndrome was stipulated by a vascular spinal cord lesion-discircular myelopathy; in some cases vascular deficit was combined with an inherent narrowness of spinal cord channel. All patients were followed-up with a 6-month interval. The results of the study allow to differentiate LAS and LAS syndrome of vascular genesis, already during the first medical examination.

Aged↗
PubMed1996

[Expression of synthetic gene for human angiogenin in E. coli cells].

A synthetic gene for human angiogenin was cloned into pRTang under control of the Proteus mirabilis recA promoter. After induction with mitomycin C, Escherichia coli cells transformed with pRTang produced an additional 14.2-kDa protein. According to electrophoretic and immunochemical analyses, this protein was identical to human angiogenin.

Angiogenesis Inducing Agents↗
PubMed1988

Sequence-specific chemical modification of double-stranded DNA with alkylating oligodeoxyribonucleotide derivatives.

Chemical modification of double-stranded (ds) DNA with alkylating oligodeoxynucleotide (oligo) derivatives, 5'-p(N-2-chloroethyl-N-methylamino) benzylamides of oligos, has been investigated. In contrast to relaxed plasmid DNAs, the superhelical molecules interact with the oligo derivatives and specific alkylation of the DNAs occurs at the regions complementary to the oligo reagents. Alkylating derivatives of oligocytidylates and pT(pCpT)6 react with corresponding homopyrimidine-homopurine tracts within ds DNA fragments due to triple helix formation.

Alkylation↗
PubMedDate not supplied

[Rhinovirus diseases: pathogenesis, diagnostics and treatment].

Contemporary data on human rhinovirus diseases and their pathogenesis are presented. Special attention is paid to complications which may be caused by rhinovirus infections in allergy-susceptible patients. Furthermore, approaches to the diagnostics and treatment of rhinovirus diseases are described. In particular, the advantages of molecular methods for the diagnostics of rhinovirus infection (based on the PCR) in comparison with cultural and immunochemical methods are pointed out. New investigations aimed at the development of specific antirhinovirus preparations--capsid-binding (Pleconaril), blocking the binding of the virus with cell receptors (ICAM, soluble) and inhibiting rhinovirus protease 3C--have been considered.

3C Viral Proteases↗
PubMedDate not supplied

[Development of PCR-test system for the detection of human adenovirus infection].

The paper deals with the development of the PCR-test system that allows the greatest possible number of human adenovirus (AdV) serotypes in the clinical samples to be tested by polymerase chain reaction. Primers have been selected on the basis of analysis of 3'-end sequences of hexon genes of 48 AdV serotypes. Five laboratory human AdV strains of different serotypes and some other DNA viruses were used to show the high sensitivity and specificity of AdV DNA detection. The proposed test system was not inferior to the Russian available analogues in sensitivity and specificity.

Adenoviridae↗
PubMedDate not supplied

[Complementary addressed modification of plasmid DNA].

The possibility to accomplish the sequence-specific chemical modification of superhelical DNA with reactive oligonucleotide derivatives was demonstrated. Plasmids containing fragments of the immunoglobulin gene were modified with alkylating derivatives of oligonucleotides complementary to a nucleotide sequence in the immunoglobulin gene. In contrast to the relaxed plasmid DNAs, superhelical DNAs (sigma = -0.1) were found to be attacked by the derivatives at the target nucleotide sequence. The efficiency of the reaction increases with the increase of the plasmids negative superhelicity. It was found also that the denatured derivatives. The sequence-specific modification of plasmid DNAs with the reactive oligonucleotide derivatives can be used for the site-directed mutagenesis and the investigation of the repair processes.

Animals↗