Biomedical subjects

E V Fedorova

Publications and source records attributed to E V Fedorova.

At least 19 recordsLinked to original sources

PubMed1997

[The possibility of performing artificial selection in vivo for a change in the mutability level in populations of mouse bone marrow stem cells].

Bone marrow cells of CBA males were transplanted to irradiated syngeneic females and after 13 days the mean frequency of blood erythrocytes with micronuclei, cloning efficiency of haemopoietic stem cells (HSC), and variability range of frequency of cells with micronuclei in spleen colonies were studied in 44 primary recipients. A wide range of variability has been shown for the indicators of mutability and cloning efficiency (0.1-1.8% for frequency of erythrocytes with micronuclei, 200-300-1500 for cloning efficiency, 0.1-0.5% for frequency of cells with micronuclei in spleen colonies of individual transplants). A weak negative correlation between the frequency of erythrocytes with micronuclei and the cloning efficiency was observed. We conclude that the difference in frequency of erythrocytes with micronuclei between HSC subpopulations is sufficiently high to carry out an artificial selection for high and low mutability in the course of transplantations. The cloning efficiency can be increased when spleen colonies are studied by micronuclear analysis. Data on the importance of such a selection in studying the behavior of "mutability" and "cloning efficiency" characters, immortalization, "aging", and death of HSC populations of CBA mice have been reported.

Animals↗

PubMed1992

Molecular organization and evolution of the D17Leh80-like loci in the mouse t complex.

We determined the sequence of Tu80, one of the molecular clones derived from microdissected fragments of Chromosome (Chr) 17. The sequence data demonstrated that Tu80 contains an open reading frame (ORF) of 204 bp. Two sequences within the ORF, one homologous to the LINE1 element and the other to the first intron of the C epsilon gene of mouse immunoglobulin, were observed. A separate sequence, homologous to Tu80, designated as NOV1, was isolated from a genomic library of mouse Chr 17. NOV1 was found to contain an inserted B2 repeat, making it structurally different from Tu80. The sequences of Tu80 and NOV1 were compared with those of LINE1 and the first intron of the C epsilon gene. The results suggest that the ancestor of the Tu80-like sequence might have arisen through recombination between a LINE1 element and the C epsilon gene. It is concluded that Tu80 and NOV1 might have resulted from duplication of an ancestral sequence followed by divergence. The comparative analysis also demonstrated a high degree of conservation of the LINE1-like sequence in Tu80 and NOV1. Based on the structure of human, rat, rabbit, and mouse LINE1 fragments, as well as those of NOV1 and Tu80, a phylogenetic tree was constructed. The available data tend to support the assumption that the ancestor for the Tu80-like sequence might have arisen not later than 27-33 million years ago.

Alleles↗

PubMed1992

[Interclonal and interpopulational differences in the frequency of spontaneous karyotypic changes in cell populations of transplantable rat rhabdomyosarcoma RA-2].

Rat organospecific transplantable RA-2 rhabdomyosarcoma substrains RA-2H (high metastatic potential), RA-2L (low metastatic potential) and RA-2T (thermal resistance) were investigated using single cell cloning technique for frequency of micronucleated cells (FMC). Significant interclonal and interpopulational differences were established. Average FMC for RA-2H was 2.96 +/- 0.13%; 5.94 +/- 0.24% for RA-2L and 1.89 +/- 0.12% for RA-2T. Clones showed 5-10 times differences in FMC in each substrain. FMC versus growth time and clone size was studied in RA-2H: average FMC dropped from 2.7% on day 9 to 0.5% on day 20 after administration and the lowest values were recorded in larger clones at each stage. Perspectives of FMC studies in tumor cell populations are discussed.

Animals↗

PubMed1992

[Structure and evolution of the D17LeH80-like locus in the murine t-complex].

The t complex in the proximal part of chromosome 17 is one of the most thoroughly studied regions of the mouse genome. We determined the sequence of Tu80, a molecular clone derived from microdissected fragments of chromosome 17. The sequence data demonstrated that the total length being 324 bp, Tu80 contains an open-reading frame (ORF) of 204 bp. Two fragments were detected within the ORF, one homologous to the LINE1-element, the other to the first intron of the C epsilon gene of mouse immunoglobin. A sequence designated NOV1 was isolated from the genomic library of mouse chromosome 17. NOV1 was found to contain a B2 insert, making in structurally different from Tu80. The sequences of Tu80 and NOV1 were compared with those of LINE1 and the first intron of the C epsilon gene. The results suggested that the ancestor of the Tu80-like sequence might have arisen through illegitimate recombination between the fragments of LINE1 and the C epsilon gene. It is concluded that Tu80 and NOV1 might have resulted from duplication of the ancestral sequence and following divergence. The comparative analysis also demonstrated high degree of conservation of the LINE1 fragments in Tu80 and NOV1, as well as in the LINE1 in a number of mammalian species. Based on the structure of human, rat, rabbit and mouse LINE1 fragments, and also on that of NOV1 and Tu80, phylogenetic tree has been constructed. Its topology is consistent with the accepted phylogenetic relationships among the species studied. The data available tend to support the assumption that the ancestor for the Tu80-like sequence might have arisen not later than 27-33 million years ago.

Amino Acid Sequence↗

PubMed1991

[Selection for decreased and increased spontaneous karyotype instability in SP2/0 murine myeloma cell populations].

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Animals↗

PubMed1987

[Cell populations of transplantable murine tumors of various degrees of histogenesis during their proliferation in the anterior chamber].

Six transplantable murine tumors of different histogenesis were investigated after transplantation to subcutaneous connective tissue (SCT) and the eye anterior chamber (EAC). Cell morphology was studied using light microscopy. DNA contents in the nuclei of tumor cells were investigated with flow cytometry technique. LDH isoenzymes were studied using electrophoresis in polyacrylamide gel. In the case of tumors with near diploid modal class, a redistribution of LDH isoenzyme activity and an increase in morphological differentiation level were obtained. In the case of tumors with modal class differing from the diploid one, a morphological structure changes were revealed, but there were no differences in LDH isoenzyme activity. The data obtained show that the capability of increasing morphological and biochemical differentiation level after cultivation in the EAC of murine transplantable tumors remains even on the late stages of progression in tumors of different histogenesis with near diploid value of modal class.

Animals↗

PubMed1985

[Isozymes of NADP-dependent isocitrate dehydrogenase in normal and tumor tissues of various mouse strains and their hybrids].

Normal tissues of DBA, CBA, CC57W, C3H, Balb/c, SHR mice and F1 hybrids CC57W/DBA appeared to differ in the ratios of mitochondrial and supernatant NADP-dependent isocitrate dehydrogenase (IDH). Tested inbred mice strains CC57W, C3H, SHR, Balb/c contain allelic form Idh-1a of supernatant IDH gene Idh-1, whereas allelic form Idh-1b is characteristic of mice strains DBA and CBA. In tumors IDH isozymes have the same mobility as do isozymes of homologous normal tissues; but their activity is lower. A high variability of each isozyme activity in the isozyme spectrum is revealed in various tissues of F1 hybrids CC57W/DBA. Allelic forms of gene Idh-1 were used as markers of normal and tumor cells for the experimental model: transplantation of sarcoma 37 (Idh-1a/Idh-1a) to subcutaneous tissue of the mouse strain DBA (Idh-1b/Idh-1b). It enables us to reveal isozymes of stromal cell in tumor IDH isozyme spectrum. The results indicate that the relation of normal and tumor isozymes vary in different tumors.

Alleles↗

PubMed1984