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I A Zamulaeva

Publications and source records attributed to I A Zamulaeva.

15 recordsLinked to original sources
PubMed2000

Determination of somatic mutant frequencies at glycophorin A and T-cell receptor loci for biodosimetry of acute and prolonged irradiation.

Somatic mutant frequencies at glycophorin A (GPA) and T-cell receptor (TCR) loci were assessed. The dependence of the GPA mutant frequency on doses of acute and prolonged irradiation was shown. In the case of acute irradiation the GPA mutant frequency displayed a three-fold greater dose-related increase as compared to prolonged irradiation. A dose-dependent increase in the TCR variant frequency was found only in a group of subjects with recent exposures. In Chernobyl clean-up workers the TCR mutant frequency was significantly higher than in control non-irradiated individuals.

Case-Control Studies↗
PubMed2000

[Investigation of fetal cells isolated from maternal blood by different methods].

This paper presents the results of investigation of the isolated from maternal blood by 4 different methods according to the optimized protocols. All women had male fetuses. The mononuclear cells with fetal erythroblasts were preisolated by using density-gradient centrifugation of the maternal blood in the Ficoll solution. Fetal cells were detected by FISH for Y-chromosomal sequences. The fetal cells were 2.1% by fluorescence activated cell sorting (FACS); 3.8% by magnetic field sorting, and 2.6% by two-stage density gradient precipitation. The fetal lymphocytes were investigated through air-cultivation of peripheral maternal lymphocytes. Their proportion was 3.9% in the culture samples. The findings lead to the conclusion that the new non-invasive approach is useful for prenatal diagnosis of chromosomal aneuploidies.

Aneuploidy↗
PubMed1999

Histones evoke thymocyte death in vitro; histone-binding immunoglobulins decrease their cytotoxicity.

Effects of various histones, poly-L-lysine, spermine, and the synthetic peptide Arg-Lys-Asn-Val-Tyr-Arg (thymohexine) on intact rat thymocytes were studied. Histones and poly-L-lysine displayed cytotoxicity, causing disorders in the membrane permeability of thymocytes and their death. The dose and time dependences of the effects of histones on thymocytes were determined. Preparations of normal human immunoglobulins bound histones but displayed neither cytotoxicity nor interaction with intact thymocytes. The immunoglobulins significantly decreased the number of dead thymocytes in the presence of total histones. However, the number of cells with detectable immunoglobulin molecules was increased in the presence of histone in the incubation medium. It is suggested that cytotoxicity depends on the number of epitopes on the cell membrane available for interaction with positively charged protein molecules.

Animals↗
PubMed1999

[A noninvasive approach to studying fetal cells for prenatal diagnosis of chromosomal aneuploidies].

Fetal cells isolated from maternal peripheral blood during the second trimester of pregnancy were analyzed. Blood samples were centrifuged in a Ficoll-Paque gradient, the mononuclear cell fraction was isolated and stained with fluorescent monoclonal antibodies against glycophorine A (GPA + PE), transferrin (CD71 + FITC), and Hoechst 33342. Fluorescence-activated cell sorting (FACS) was conducted on a Vantage flow cytofluorimeter (Becton Dickinson). Fluorescence in situ hybridization (FISH) with Y chromosome-specific DNA probe revealed fetal cells that exhibited Y signal in all 20 blood samples obtained from women pregnant with healthy male fetuses. The concentration of these fetal cells averaged about 1.34% and ranged from 0.1 to 4.2% in different blood samples. In six cases, blood samples were obtained from pregnant women, in which prenatal cytogenetic analysis revealed various fetal aneuploidies. Using FISH with DNA probes specific for chromosomes X, 18, and 13/21, Fetal cells with chromosomal aberrations were detected in these six maternal blood samples at a concentration from 1.5 to 5.6% (on average 3.7%). These results indicate the possibility of a new noninvasive approach, which is safe for both mother and fetus when used for isolation of fetal cells from pregnant women's blood samples and prenatal diagnosis of a broad spectrum of fetal cell chromosomal aberrations.

Aneuploidy↗
PubMed1998

Determination of somatic mutant frequencies at glycophorin A and T-cell receptor loci for biodosimetry of prolonged irradiation.

PURPOSE: To determine the variant frequencies (VF) at glycophorin A (GPA) and T-cell receptor (TCR) loci in persons exposed to prolonged ionizing radiation at different doses and to assess the significance of the GPA and TCR assays for biodosimetry of prolonged irradiation. MATERIALS AND METHODS: The VF values were determined by means of flow cytometry in 120 persons exposed between 1968-1996. Most exposures were in Chernobyl clean-up workers in 1986-1987. RESULTS: A significant correlation was shown between the NO GPA variant cell frequency and dose (r = 0.61, p < 0.0001). The slope of the linear regression was 6.3 x 10(-6) NO mutant cells/Gy. Dose-dependent increase in the TCR VF was found in the group with recent exposures (slope 2.1 x 10(-4) variant cells/Gy, r = 0.75, p = 0.0002). In the Chernobyl clean up workers who received doses less than 0.25 Gy the TCR VF unlike the GPA VF was significantly higher than in the control non-irradiated individuals (p < 0.01 and p > 0.05 respectively). CONCLUSIONS: The GPA assay has limited potential to be used as a biodosimeter of prolonged irradiation, at least in dose interval up to 2.0 Gy. The TCR assay is likely to have greater potential in estimation of recent radiation exposure than the GPA assay.

Adult↗
PubMed1997

Natural hidden antibodies reacting with DNA or cardiolipin bind to thymocytes and evoke their death.

Both free and hidden natural antibodies to DNA or cardiolipin were obtained from immunoglobulins of a normal donor. The free antibodies reacting with DNA or cardiolipin were isolated by means of affinity chromatography. Antibodies occurring in an hidden state were disengaged from the depleted immunoglobulins by ion-exchange chromatography and were then affinity-isolated on DNA or cardiolipin sorbents. We used flow cytometry to study the ability of free and hidden antibodies to bind to rat thymocytes. Simultaneously, plasma membrane integrity was tested by propidium iodide (PI) exclusion. The hidden antibodies reacted with 65.2 +/- 10.9% of the thymocytes and caused a fast plasma membrane disruption. Cells (28.7 +/- 7.1%) were stained with PI after incubation with the hidden antibodies for 1 h. The free antibodies bound to a very small fraction of the thymocytes and did not evoke death as compared to control without antibodies. The possible reason for the observed effects is difference in reactivity of the free and hidden antibodies to phospholipids. While free antibodies reacted preferentially with phosphotidylcholine, hidden antibodies reacted with cardiolipin and phosphotidylserine.

Animals↗
PubMed1996

Prognostic significance of S-phase fraction detected by antithymidine antibodies in epidermoid cervix carcinomas.

PURPOSE: To assess the predictive value of pretreatment proliferative activity of epidermoid cervix carcinoma cells with respect to short- and long-term results of radiotherapy. METHODS AND MATERIALS: The proliferative activity of 25 epidermoid cervix carcinomas was evaluated as the immunofluorescent labeling index (LI) by rabbit antithymidine antibodies reacting specifically with single-stranded DNA of replication forks in S-phase cells. The short-term clinical outcome was estimated at 3-6 months after treatment by visual and palpatory examination. Three-year follow-up data were obtained through hospital charts and correspondence with referring physicians for only 19 patients. RESULTS: There was no statistically significant association between LI and such conventional prognostic factors as clinical stage. The LI value of cervix carcinomas was significantly associated with complete regression at 3-6 months after radiotherapy and 3-year disease-free survival. Complete regression at 3-6 months was observed in 87.5% patients with fast proliferating tumors (LI > 7.0%), and only in 41.2% patients with slowly proliferating tumors (p = 0.03). Probability of 3-year disease-free survival was 85.7% in patients with fast proliferating tumors and 50.0% in those with slowly proliferating tumors (p = 0.05). CONCLUSIONS: The immunofluorescent LI of epidermoid cervix carcinoma is able to provide prognostic information on short-term tumor response to radiotherapy and disease-free survival.

Adult↗
PubMed1991

[DNA replication in mammalian cells after the action of physical, chemical or biological factors. VI. The recovery of DNA synthesis in a culture of irradiated cells].

The kinetics of DNA synthesis restoration in cultured HeLa cells and in L-929 mouse fibroblasts irradiated by gamma-rays of 60Co with a dose of 10 Gy was studied. Early after irradiation the rate of DNA synthesis in HeLa cells measured with 3H-thymidine incorporation was seen to decrease. Two hours later the incorporation starts to increase to reach the control level 4 hours after irradiation and then becomes even higher than this level. The distribution of cells among phases of the cell cycle measured with flow cytometry undergoes changes. 4-6 hours after irradiation part of S-phase cells increased contributing presumably to the elevating of 3H-thymidine incorporation observed at this time. The restoration of the incorporation was suppressed by inhibitors of protein and RNA synthesis--cycloheximide and actinomycin D. It is suggested that the processes of restoration of DNA synthesis in irradiated cells can be of inducible nature. In irradiated HeLa and L-929 cells the restoration of DNA synthesis is resistant to novobiocin, an inhibitor of DNA replication.

Animals↗
PubMed1986

[Concentration and distribution of insulin and insulin-like protein in the organs of normal and diabetic mice].

Presence of insulin or insulin-like protein has been studied in mouse liver, kidneys, lungs, duodenum, jejunum, submandibular and parotid salivary glands, in femoral, diaphragmal and abdominal wall muscles by means of the immunofluorescent method. In order to understand the role of the extrapancreatic insulin for compensation of the insular insufficiency, corresponding organs have been examined in mice with alloxan diabetes. The immunoreactive insulin is proved to be present only in cells of the granular parts of the salivary tubules of the submandibular and striated ducts of the parotid glands. As demonstrates microfluorometry, a relative amount of insulin in the submandibular gland cells is 1.5 times and in the parotid gland cells--2 times as small as in beta-cells of the pancreatic glands. Under alloxan diabetes insulin content in the salivary gland cells decreases by 1.3-1.9 times (in the beta-cells--by 2.7 times). This may designate that the extrapancreatic insulin (or insulin-like protein) participates in compensation of hypoinsulinemia. In mice with alloxan diabetes, immunoreactivity of insulin is also revealed in hepatocytes.

Alloxan↗
PubMedDate not supplied

[The combined action of gamma irradiation and hyperthermia on the structure of the cell population in the Chinese hamster].

A change in the structure of FAF-28 Chinese hamster cell population occurred during 24 h following gamma-irradiation or hyperthermia heating, or the effect of both factors was studied by flow cytofluorometry. With radiation delivered immediately after heating the distribution of cells among cycle phases was nearly the same as with hyperthermia alone: the share of cells at the S-phase was invariable during the first 4-6 h, then it slowly diminished; at G1 it slowly decreased and at G2 increased. When irradiation preceded heating the pattern of cell redistribution during the first hours was the same as that with radiation alone: the "wave" of transition from G1 to S phase was the same, but shorter in amplitude and longer in time; then cells were accumulated at G2+M and remained there for 24 h. Thus, of the two factors applied, the first was the major one in changing the cell population structure during the first hours after treatment. In 24 h the result was the same, that is, the considerable accumulation of cells at G2+M.

Animals↗
PubMedDate not supplied

[The effect of irradiation on the growth of human laryngeal tumors transplanted under the kidney capsule of immunocompetent mice].

A study was made of the influence of gamma-radiation on the growth of human larynx squamous cell carcinoma transplanted under the capsule of the kidney of immunocompetent mice. The transplants were shown to increase in size 6 days after transplantation. Irradiation of animals 24 h after transplantation inhibited considerably the tumor growth. However, the preirradiation (24 h before operation) inhibited the growth of nonirradiated transplants to the same extent as the exposure of mice with the transplanted tumor fragments did: the radiation dose that induced 50% inhibition of the growth was 4.5 Gy and 5.3 Gy, respectively. Preliminary data indicate that tumor fragment of patients with the unfavourable prognosis increase in size and respond to radiation to a lesser extent.

Animals↗
PubMedDate not supplied

[The combined effect of ionizing radiation and benzene on immunoreactivity indices in the spleen and lymph nodes].

Under the influence of the combined action of gamma irradiation (1 Gy, 1,15 Gy/min) and benzene the synergistic reduction of proportion and absolute content of B-cells and less expressed reduction of absolute content T-cells in spleen and lymph nodes was observed. In spleen the thymus-dependent humoral immune response was resistant to combined effect of irradiation and benzene, while in lymph nodes it was highly sensitive. The profound suppression of antibody formation in lymph nodes was characterized by synergism. It was accompanied by the block of specific recruitment of antigen sensitive cells within drained lymph nodes from migrating stream. The suppression of local immune response resulting from the combined effect of radiation and toxicants may be the cause of protective immunity disturbance.

Animals↗
PubMedDate not supplied

[Determination of mutation frequency at loci of glycophorin A and T-cell receptors: informativeness for biological dosimetry of acute and prolonged irradiation].

The frequencies of somatic mutations at loci of glycophorin A (GPA) and T-cell receptor (TCR) were determined in persons exposed professionally to ionizing radiation or a result of accidents at nuclear power plants and in control donors. Dependence of glycophorin A mutant (NO) cell frequency on doses of acute (up to 3.5 Gy) and prolonged (up to 15.0 Gy) irradiation was shown. The slope of linear regression corresponded to increase of NO-mutant frequency by 31.1 x 10(-6)/Gy (r = 0.87, p < 0.0001) for acute irradiation and by 6.3 x 10(-6)/Gy (r = 0.61, p < 0.0001) for prolonged one. The 5-fold decrease of the linear regression slope in the case of prolonged irradiation makes significantly worse permissive ability of the GPA test. Therefore its use for biological dosimetry of prolonged irradiation is not expedient in dose interval up to 1 Gy. The frequency of mutations in genes of T-cell receptor significantly correlated with dose of irradiation only in group of donors with recent radiation exposure (r = 0.75, p = 0.0002). Meanwhile, the TCR method is more sensitive and informative for biological dosimetry of recent radiation, than the GPA test.

Adolescent↗
PubMedDate not supplied

[Determination of mutation frequency at loci of glycophorin A and T-cell receptor: study of Chernobyl AES accident cleanup workers].

The frequencies of somatic mutations at loci of glycophorin A (GPA) and T-cell receptor (TCR) were determined in control unexposed donors and Chernobyl clean up workers, who received low doses of irradiation up to 0.25 Gy. High variability of mutant rates for two investigated genes was shown in the clean up workers. No significant difference in the GPA (NO) mutant frequencies was observed between the clean up workers and control donors (p > 0.05), though there is a tendency for increasing the GPA mutation rate in the clean up workers. Meanwhile, the TCR mutation rate was significantly increased the clean up workers (p < 0.01), perhaps because of acceleration of spontaneous mutagenesis and possible genome instability. Persons with elevated levels of mutations at two loci can present a group at high risk in respect to oncological diseases.

Adult↗