Evaluation of genotoxic effects of lead in pottery-glaze workers using micronucleus assay, alkaline comet assay and DNA diffusion assay.

PURPOSE: We investigated genotoxic effects of occupational exposure to lead acetate in pottery-glaze ceramic workers. METHODS: The study was carried out in 30 exposed workers and 30 matched controls, to whom several biochemical parameters-the blood lead (B-Pb; range: exposed, 41.68-404.77; controls, 12-52) and cadmium (B-Cd) level, the activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), the level of vitamin B(12) and folate in serum-were measured. The genotoxic effects were evaluated by the alkaline comet assay, the DNA diffusion assay and micronucleus test in peripheral blood lymphocytes. RESULTS: Subjects exposed to lead had significantly higher B-Pb level and, consequently, increased values of tail intensity (TI), frequency of apoptotic and necrotic cells, and frequency of micronuclei (MN). In contrast, their activity of ALAD, the level of vitamin B(12) and folate in serum were significantly lower compared to controls. Poisson regression analysis showed a significant correlation of profession, duration of exposure, smoking, level of cadmium in blood, ALAD and EP with primary DNA damage. A majority of primary damage repairs in a short period after exposure to a genotoxic agent. In addition, the influence of gender and level of vitamin B(12) and folate in serum MN frequency in exposed group was observed. CONCLUSIONS: In this study, DNA diffusion and micronucleus test showed higher influence of tested parameters to DNA damage. The results indicate a need for concomitant use of at least two different biomarkers of exposure when estimating a genetic risk of lead exposure.

Tissue extract from Eisenia foetida as a wound-healing agent.

BACKGROUND AND OBJECTIVES: This study was aimed at demonstrating the influence of Eisenia foetida earthworm extract (G-90) on wound healing in an animal model. Medicinal properties of earthworms have been long known, especially in Eastern countries. MATERIALS AND METHODS: Four groups of Wister rats (36 in each group) were wounded under anaesthesia; the skin was surgically incised in a circular manner (the circular incision in reference measuring 2 cm in diameter) and afterwards daily treated for 24 days in a following manner: Group 0--the control group deprived from any treatment whatsoever; Group 1--treated with physiological saline solution; Group 2--treated with Panthenol D and serving as a positive control, and Group 3--treated with G-90 (10 ng/ml). The animals were sacrificed on days 3, 6, 9, 12, 18 and 24 post wounding and the diameter of wound was measured by virtue of photometric method. The excised wounds were routinely fixed and embedded into paraffin section and dully stained for histopathological analysis. The presence of microorganisms on the wounds was assessed as well. RESULTS: The best antibacterial wound shielding was achieved with G-90 treatment. Besides antibacterial shielding, the wounds treated with G-90 were also protected from inflammation. G-90 was shown to shorten the inflammatory, and accelerate the proliferative and the maturation phase, stimulating thereby the regeneration of an injured epidermis. Statistical analysis revealed G-90 (p=0.018) to be superior over other treatments. CONCLUSIONS: Thus, Eisenia foetida earthworm extract (G90) might be considered as a new wound-healing agent suitable for use in both veterinary and human medicine practice.

Cytogenetic changes in subjects occupationally exposed to benzene.

Humans are exposed to benzene from various occupational and environmental sources. The genotoxic effects of benzene were assessed in peripheral blood lymphocytes of 36 workers employed in the shoe industry for a period extending from seven months to over 30 years. Chromosomal aberrations and sister chromatide exchanges were used as indicators of genotoxic effects. The incidence of dicentric chromosomes in the exposed group was significantly higher than in the control group (P < 0.05). No significant increase was detected between the working period in the exposed group and chromosomal aberrations. Sister chromatide exchange (SCE) frequency was not significantly increased in the exposed group.

Analysis of sister chromatid exchange and micronuclei in peripheral blood lymphocytes of nurses handling cytostatic drugs.

The genotoxic effect of occupational exposure of 20 nurses who handled cytostatic drugs in medical oncology and haematology units was evaluated by micronucleus and sister chromatid exchange test. The duration of employment in the units and of exposure to cytostatics ranged from 1 to 31 years. The exposed nurses manifested an increase in cells with micronuclei as compared to the control group (P < 0.05). Nurses exposed to cytostatic drugs for 20-31 years showed a higher frequency of micronuclei (P < 0.05), whereas there was no difference in frequencies between the control group and the group exposed for 1-14 years (P > 0.05). The influence of the exposure period proved to be a significant parameter for the micronucleus test. No statistically significant differences were observed in sister chromatid exchange (P > 0.05).

Chromosome aberrations in operating room personnel.

BACKGROUND: Long-term occupational exposure to volatile anesthetic agents may result in various adverse health effects. Additionally, certain surgical procedures involve exposure to the other agents such as X rays. Identification of chromosome damages in peripheral blood lymphocytes serves as a useful indicator of exposure to mutagenic agents. METHODS: The frequency of chromosomal aberrations was assayed in peripheral lymphocytes obtained from 129 subjects working in operating theatres and 41 control subjects. RESULTS: The results show an increased rate of chromosome aberrations in the exposed subjects. The differences in frequency of chromosome aberrations between particular job tasks were not distinct. Acentric fragments in anesthesiologists and dicentrics in surgeons seem to stand out. CONCLUSIONS: As the findings do not differ significantly between the exposed groups, one can hardly distinguish radiation and anesthetics effects from one another.

Radiation-induced chromosomal aberrations and haematological alterations in hospital workers.

Long-term exposure to low doses of ionizing radiation may affect cells and tissues and result in various adverse health effects. The purpose of this study was to investigate whether chromosome aberrations and haematological alterations could be used as biomarkers of possible radiation injury in workers exposed to ionizing radiation. Groups totalling 323 medical professionals handling X-ray equipment and 160 control subjects were examined for incidence of chromosome aberrations and changes in leukocyte, lymphocyte and thrombocyte counts. The incidence of all types of chromosome aberrations was higher in the exposed groups than in controls, yet no significant difference was found between the exposed groups. A many-fold increase in chromosome aberration frequency in all exposed groups was not followed by a corresponding haematological depression. This suggests that chromosome aberrations are a significantly more sensitive indicator of changes caused by low doses of ionizing radiation than haematological alterations.

[Biological effects of the iodine 131 radionuclide]. / Bioloski ucinci radionuklida joda-131.

Radionuclides released into the biosphere by local sources are added to artificial radionuclides introduced by atmospheric nuclear weapon tests or nuclear accidents. The main polluters are nuclear industry reprocessing plants and nuclear power stations. Other sources are hospitals using radionuclides for diagnostics and therapy. This article presents the effects of radioisotope iodine-131 on a living organism, on the cell and on the genetic material within the cell. Beside the accident iodine-131 contamination, its wide diagnostic and therapeutic application attributes to the total radiation dose. The biological distribution of this radiopharmaceutical in the body depends on the way of use and on the and physical and chemical shape of this radiopharmaceutical. A few minutes after the administration, all iodine ingested or inhaled is rapidly absorbed by blood. The irradiation dose in blood depends on the administered amount of 131I and the fraction passing into the plasma as protein-bound 131I. After entering the organism, iodine mostly accumulates in the thyroid gland. The effect of ionized radiation on living cells are proportional to the dosage of 131I. Intracellular radioactive decay occurs in cytoplasm, in karyoplasm, and in the DNA molecule incorporated fraction. Beside the damage resulting from the deposition of radiation energy, 131I causes biological damage when it decays while the isotope is incorporated into the DNA of human cells. Certain beta/gamma-emitting isotopes such as 131I may be particularly hazardous when incorporated into DNA. Incorporation of radioactively labeled compounds into the DNA leads to highly selective irradiation of the nucleus of the proliferating cells. This produces pronounced biological damage as the genetic material in the cell nucleus constitutes the most radiosensitive target within the cell.

Chromosome aberrations in peripheral blood lymphocytes from control individuals.

This study emphasizes the problems encountered in obtaining suitable control levels for comparison with occupational studies of exposure to clastogens. Blood samples taken from 135 individuals (69 females and 66 males) were examined for chromosome aberrations. The data include 15,368 cells scored for chromosome aberrations. The frequencies of chromatid and chromosome breaks, acentric fragments and dicentrics were determined. The frequency of the most common chromosome aberration, chromosome breaks, was 1.1 x 10(-2) and for dicentrics 0.26 x 10(-3). The values obtained were investigated in relation to sex, cigarette smoking habits, diagnostic X-ray exposure and use of antibiotics. In all the parameters, no significant differences were found.

A new source of biologically active compounds--earthworm tissue (Eisenia foetida, Lumbricus rubelus).

1. Earthworms possess immunological recognition and memory as well as high regenerative abilities. Coelomic fluid was used as a source of biologically active compounds. 2. A biologically active glycolipoprotein extract from a whole earthworm tissue homogenate was isolated and named G-90. 3. G-90 forms precipitation arcs in gel with different animal and human sera. 4. It alters murine cell growth rate in vitro in serum in a dose-dependent manner and slows murine tumor growth in vivo. 5. G-90 does not contain mutagens or carcinogens.