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Biomedical subjects

L A Naumova

Publications and source records attributed to L A Naumova.

At least 19 recordsLinked to original sources
PubMed2000

Instability of bronchial epithelium in chronic pulmonary diseases.

Pathomorphological examination of large bronchi in patients with occupational diseases, lung cancer, and in subjects exposed to radiation revealed structural and functional heterogeneity of the epithelium: the presence of focal atrophy, metaplasia, hyper- and dysplasia in the same biopsy specimen. This phenomenon was termed as instability of the epithelium. Thickness of the epithelium greatly varied, especially, in neoplastic processes. Atrophy and epithelial instability phenomenon are interpreted as morphological markers of ecological and oncological risk.

Autoradiography↗
PubMed1994

[The clinical and structural-metabolic characteristics of atrophic forms of chronic bronchitis].

A clinical-morphological study of bronchobiopsies from 78 patients with endoscopic picture of atrophic endobronchitis was carried out. Two forms of morphogenesis of chronic atrophic process in the bronchial mucosa are distinguished: primary dystrophic and primary inflammatory. Primary dystrophic bronchopathy is a clinical manifestations of the first form which presents structurally and functionally as primary dystrophy and atrophy of the bronchial mucosa in combination with sclerosis of the lamina propria in a sharp decrease of synthetic processes in bronchial epitheliocytes as indicated by the data of autoradiography. The primary inflammatory form of atrophic process has clinical symptoms typical for inflammatory process and is characterized by gradual reorganization in the bronchial wall and by maintaining sufficiently high level of metabolic reactions in bronchial epitheliocytes.

Adolescent↗
PubMed1987

[Phenomenon of restriction alleviation in Escherichia coli strains].

The alleviation of foreign DNA restriction after treatment of cells by UV and gamma-rays or ocr+-gene product of T3, T7 phages has been studied. Both UV and gamma-radiation were shown to induce in restriction alleviation of unmodified phage. The results of restriction alleviation caused by T3 and T7 ocr+-gene products have been evaluated by F-lac+ transfer efficiencies in heterologic crosses and plating of unmodified phage lambda. The phenomenon of restriction alleviation was established to depend on the strain used and to be expressed mostly in AB157 and its derivatives.

Bacteriophage lambda↗
PubMed1984

[Dependence of Escherichia coli K-12 viability and mutability on the balance of DNA and protein syntheses. VI. Molecular mechanisms underlying the phenomena of imbalance death and metabolic mutagenesis].

In this report the results of further studies of the molecular mechanisms of the disbalance death and metabolic (disbalance) mutagenesis are presented. As reported previously, the relationship of viability and mutability of Escherichia coli cells from the extent disturbance of DNA-protein synthesis balance is determined by the processes of stabilization and repair of metabolic disbalance gaps in DNA strands. It is established that polB, recB, SSB gene products are involved in the processes of stabilization and repair of metabolic disbalance gaps.

Bacterial Proteins↗
PubMed1982

[Effect of polB mutation on the nature of the thymineless death of thy- cells of Escherichia coli K-12].

Cell survival, the rates of DNA and protein synthesis, stabilization and repair of single-stranded DNA breaks were measured for Escherichia coli K-12 pol+, polA1, polB1, polC(ts) cells during thymine deprivation. The results indicate that single-stranded breaks in DNA induced by thymine deprivation play no major role in thymineless death of thy- polB- cells, which is similar to thy recB mutant lacking exonuclease V. Probably, the dependence of exonuclease V activity on the presence of DNA polymerase II (the polB gene product) exists which determines molecular mechanisms of thymineless death of thy- polB- cells.

DNA Repair↗
PubMed1980

[Relation between Escherichia coli K-12 viability and mutability and the balance between DNA and protein synthesis. III. Relation between disruptions in the balance between DNA and protein synthesis and mutagenesis and viability during thymidine deprivation of thy- cells defective with respect to recB and polA genes].

The phenomenon of metabolic mutagenesis is found to be determined by stabilization of metabolic breaks in DNA chains, being linked with disbalance of intracellular synthesis of DNA and protein. The rate of metabolic mutagenesis observed in case of the DNA-protein synthesis disbalance due to thymine starvation is influenced by cell genotype. The lack of exonuclease V in recB-thy- cells decreases (reduces) the rate of metabolic mutagenesis and does not effect the viability. The lack of DNA polymerase I activity in polA-thy- cells causes a sharp increase in the metabolic mutagenesis rate and a parallel sharp drop in the survival under thymine starvation, as compared to cells with polA+thy- genotype.

Bacterial Proteins↗