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T V Medvedeva

Publications and source records attributed to T V Medvedeva.

4 recordsLinked to original sources
PubMed2004

[MIRU-VNTR genotyping of Mycobacterium tuberculosis strains from East Siberian: Beijing family versus Kilimanjaro family].

Seventy-two M. tuberculosis strains isolated from patients in different regions of East Siberia were studied by MIRU-VNTR repeats. Phylogenetic trees of relationship between the studied strains and of those from other world regions were investigated by phylogenetic analysis, i.e. NJ, UPGMA and ML. Phylogenetic evidence is provided for the prevalence of Beijing and Beijing-like strains (71%) in the above region. Besides, there was found a group of strains (115%) with the robust genotype which was given the name of ASU (African-Siberian-Ural). A linkage between MIRU10 (5-10 repeat) and MIRU26 (single repeat) was established as a predominant ASU sign. According to preliminary results, apart from Siberia, ASU strains can be encountered in the Urals and Africa (Tanzania, Kilimanjaro genotype). MIRU-VNTR consensus of ASU for East Siberia is 22( > 6)225113233.

DNA, Bacterial↗
PubMed2002

[Estimation of the efficiency of ERIC-PCR typing of Mycobacterium tuberculosis for evaluation of the prevalence of antibiotic-resistant strains].

Twenty-four antibiotic-resistant and sensitive strains of M. tuberculosis isolated from different territories of the Irkutsk region (East Siberia) were studied using PCR genotyping by enterobacterial repetitive intergeneric consensus (ERIC). Evolution relationships are illustrated by phylogenetic trees as a result of analysis by UPGMA and ML approaches. It was found that the studied samples belonged to two genetically different groups, both of which included sensitive and resistant strains. The sensitivity of the method was calculated by the Hunter-Gaston index. Based on these data, a probable pattern of emergence and propagation of antibiotic-resistant forms of tuberculosis in the studied region is discussed.

Bacterial Typing Techniques↗
PubMedDate not supplied

[Cloning of tobacco DNA fragment with promoter properties in a transgenic plant].

A selection system for isolating DNA sequences with transcription-promoting activity by their functioning in bacterial cells has been proposed. Tobacco nuclear DNA fragments were inserted in front of the promoterless neomycin 3'-phosphotransferase II (NPT-II) gene and promoter-like sequences were identified by their ability to restore NTP-II activity in E. coli cells. One of these recombinant plasmids was introduced in tobacco protoplasts by direct gene transfer and transformed calli were isolated by kanamycin selection. The NTP-II expression in regenerated transgenic plants were highest in root, slightly lower in stem and were practically absent in leaf. Sequence analysis of cloned segment showed the presence of conserved sequences essential for promoter activity in eukaryotic cells. A transcription start site was observed by S1 mapping. The size of protected fragments corresponds to the initiation of transcription 176 and 179 base pairs upstream the initiation codon in tobacco and 75 base pairs in E. coli.

Base Sequence↗