Cytome analysis (micronuclei and nuclear anomalies) in bioindication of environmental pollution in animals with nuclear erythrocytes.

Assessment of cytogenetic homeostasis of indicator animals is of great importance in ecological monitoring. The simplest method of its study is micronucleus analysis. Animals with nuclear erythrocytes are often used as indicator animals.

IMPACT OF SMOKING HABITS ON THE STATE OF CHROMATIN AND MORPHOLOGY OF BUCCAL EPITHELIAL CELLS AMONG MEDICAL STUDENTS.

The cells of buccal epithelium were investigated in groups of smoking and non-smoking students. Cell samples were collected by scraping with blunt sterile spatula, stained with orcein and photographed. The smoking of cigarettes and hookah induces significant decrease in nuclear and cell perimeter and cell area in cells of buccal epithelium.

Very early effect of DMBA and MNU on microRNA expression.

Background: microRNA expression profile analysis provides evaluation of the early stages of carcinogenesis. This study focuses on early alteration of miRNA expression after treatment with different carcinogens.

Materials And Methods: Mice were intraperitoneally injected with one dose of 7,12-dimethylbenz(α)anthracene (DMBA) and N-methyl-N-nitrosourea (MNU).

DMBA induces deregulation of miRNA expression of let-7, miR-21 and miR-146a in CBA/CA mice.

Background: 7,12-Dimethylbenz(α)anthracene (DMBA) is a carcinogen capable of inducing various types of tumors.

Materials And Methods: We investigated the effect of DMBA on micro-RNA expression in CBA/CA H2(k) inbred mice after 24 hours and one week from exposure.

Results: Expression levels of miR-21, miR-146a and let-7a were significantly higher in the vital organs of the mice 24 hours after DMBA exposure compared to those of the controls.

[Impact of microRNAs on molecular epidemiology].

Cancer research concerning short non-coding RNA sequences and functionally linked to RNA interference (RNAi) have reached explosive breakthrough in the past decade. Molecular technology applies microRNA in extremely wide spectrum from molecular tumor prediction, diagnostics, progression monitoring and prevention. Functional analysis of tissue miRNA and cell-free serum miRNA in posttranscription and translation regulation innovated and restructured the knowledge on the field.

Association between allelic polymorphisms of metabolizing enzymes (CYP 1A1, CYP 1A2, CYP 2E1, mEH) and occurrence of colorectal cancer in Hungary.

Background: Genetic polymorphisms of metabolizing enzymes may affect the risk of cancer formation in humans. Since the diet can contain polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HAs), the relationship between polymorphisms of enzymes involved in PAH and HA metabolism and the occurrence of sporadic colorectal cancer was studied.

Patients And Methods: Five hundred colorectal cancer patients and 500 controls were genotyped for cytochrome P450 enzymes (CYP) 1A1 Ile/Val, CYP 1A2*1F, CYP 2E1 c1/c2, microsomal epoxy hydrolase (mEH) exon 3 Tyr113His and exon 4 His139Arg polymorphisms by allele-specific polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism (RFLP).

[A comparative study of the ectophosphatase activity in different subpopulations of tumor cells].

Activities of ectophosphatases (alkaline phosphatase, 5'-nucleotidase and ecto-ATPase) from different subpopulation of lymphoma NKLy and ovary tumor of rats were investigated. A strong positive correlation has been shown between these activities in different subpopulations. A negative correlation between proliferative activity and activities of ectophosphatases was determined.

[Osmotic homeostasis and radiosensitivity of NKLy lymphosarcoma cells].

In experiments with cells of ascites NKLy lymphoma differing in ploidy and position in the cell cycle, a study was made of the radiosensitivity, osmotic homeostasis peculiarities and thermoradiation changes in potassium content. It was shown that the resistance of osmotic homeostasis of NKLy cells to thermoradiation correlated with their radioresistance and was maximally displayed in cells at the stage of DNA synthesis.

[The surface charge of NKLy ascitic tumor cells differing in their proliferative activity, in their place in the cell cycle and in their ploidy].

The NKLy ascitic tumor cells in the stationary phase of growth were fractionated by velocity sedimentation method. Cells from the obtained fractions were characterized by measurements of DNA contents and 3H-thymidine incorporation. The surface properties of the cells from five fractions, differing in proliferative capacity, stage of the cell cycle and ploidy were considered using cell electrophoresis, two polymer aqueous phase system and Alcian blue sorption.

[Effect of irradiation on the cellular sensitivity of separate NKLy tumor subpopulations to the membrane-toxic action of natural killers].

A study was made of sensitivity of NKLy tumor fractions, differing in the proliferative activity, position in the cell cycle, and ploidy, to membrane-toxic action of natural killer cells from mouse spleen. The membrane toxicity index for cells of three out of five fractions under study was shown to decrease after exposure to 4 Gy radiation. It is concluded that there is no correlation between NKLy cell sensitivity to membrane-toxic effect of natural killer cells and their radiosensitivity as well as their ability to repair potentially lethal damages.

[Effect of x-rays on the sensitivity of cells of the murine NKLy tumor to the membrane toxic effect of natural killers].

A study of membrane toxicity of allogenic splenocytes with regard to irradiated mouse NKLy lymphosarcoma cells (tested by the release of 3H-uridine label from target cells in the presence of exogenous RNAses) has displayed an insignificant increase, as compared with the control, in the membrane toxicity with radiation doses of 1-2 Gy and its decrease at higher doses.

[Clonogenic capacity, radiosensitivity and recovery from potentially lethal damage in individual subpopulations of the murine NKLy ascitic tumor].

Effectiveness of the diffusion chamber cloning of subpopulations of cells isolated by the sedimentation method from intact and exposed (5 Gy) mouse tumors NKLy was determined. It was shown that cells at the G2-M stages were highly radiosensitive. The recovery from potentially lethal damages was maximum at the G0-G1 stages of the cell cycle.