T. G. Tsvetkova

Learn More
An X isochromosome for the long arm was studied in 3 patients with Turner's syndrome using the BrdUrd-Hoechst 33258-Giemsa method and C-staining. In all 3 patients studied, the long arms of the i(Xq) were asymmetrical with respect to chronology of DNA synthesis. The most striking asynchrony of DNA replication was observed in large early replicating segments(More)
Blood samples were taken from 8 volunteers (21 to 26 years of age) for 7-day immersion 7 days prior to, on days 3 and 7 of the experiment and on days 1 and 8 of recovery. Serum was analyzed for 38 biochemical markers of the functional state of the myocardium, skeletal muscles, hepatobiliary system, kidney, pancreas, GI tract, prostate, and protein-nucleic,(More)
Most human somatic cells have no telomerase activity. This leads to terminal underreplication of chromosomes and, hence, proliferative ageing of cells. We studied the consequences of introduction of the gene of the catalytic component of human telomerase hTERT in the normal fibroblasts of adult human skin. The expression of this gene led to the appearance(More)
A study was done regarding the effect of the oxidizing agent potassium chromate (K2CrO4, PC) on cultured dermal fibroblasts of a healthy donor and three patients with rheumatoid arthritis (RA). Characteristics of the rRNA gene (RG) complex—RG copy number, active RG (ARG) dosage, and 18S rRNA content—were determined for each cell line. In cells of the(More)
In this work a molecular-cytogenetic characteristic has been given to the alpha-satellite DNA of chromosome 6. Using different restrictases made it possible to evaluate structural heterogeneity of the obtained subgroup of the alphoid DNA. Polymorphic restriction fragments of DNA have been found which can be used in determining linkage groups.
Cytogenetic characters of the nucleolus organizer regions (NORs) located on the short arms of five acrocentric chromosomes were studied in chromosome preparations obtained from cultured blood cells of 17 donors. In situ hybridization to a 3H-labeled probe was used to estimate the relative copy number of ribosomal genes (RGs) in all NORs of chromosomes(More)
Human rRNA genes contain variable regions, one of which is located in nontranscribed spacers (NTSs) closely downstream from the 3′-end of the transcribed region. This polymorphism may be detected by means of blot hybridization analysis as a set of distinct restriction fragments corresponding to this part of the rRNA genes. We have analyzed DNA of 51(More)
Morphology of the fibroblasts X-chromosomes obtained from the female field vole Microtus agrestis and cultured for 4--5 hr before fixation in 5-bromodeoxyuridine, was studied. A clear differential condensation along the lenght of the whole X-chromosome was observed. A difference between homologues in the degree of uneven condensation was noted both in the(More)