Micronucleus Assay Of Buccal Mucosal Cells In Smokers And Non–Smokers

The micronuclei assay (MA) in exfoliated buccal cells is an innovative technique which holds promise for the screening of epithelial carcinogens/mutagens. Micronucleus is the small nucleus that forms whenever a chromosome or a fragment of a chromosome is not incorporated into one of the daughter nuclei during cell division. The micronucleus is thought to be an indicator of DNA damage consequent to possible carcinogen exposure. The objectives of our study were to evaluate the frequency of micronuclei in exfoliated buccal mucosal cells of smokers and non–smokers and to correlate the mean micronuclei with period of smoking. Buccal smears obtained from 68 age matched male subjects (40 smokers, 28 non–smokers) were included in the study. Papanicoloau stained smears were screened for micronuclei as per Tolbert et al criteria, with 1000 cells being examined in both categories. Results showed a statistically significant difference in the mean micronuclei count in buccal cells of smokers as compared to non smokers. Micronucleus assay can be used as a simple bio–marker for screening of pre–malignant changes in cells.

The Chromosomal DNA Damage in Buccal Mucosa Cells among Schools Children in The Vicinity Of Mobile Base Stations in Selangor

Abstract@#Introduction: The increased use of mobile phones has increased the mobile base stations (MBS) deployment. While understanding of radiation protection is growing among the public, questions regarding early-life exposure to radiofrequency radiation (RFR) from MBS in children are of importance as to whether it will raise the chances of developing chronic diseases during adulthood. Taking into account the sitting location of MBS, the purpose of this study is to evaluate the chromosomal DNA damage in buccal mucosal cells between school children exposed to RFR emitted from base station antennas. Method: This is a comparative cross-sectional study in which two group of school children were sampled i.e. exposed groups are children whose school located near MBS (≤200 meters); unexposed groups are children whose school located distant far from the MBS (>200 meters). Digital RF Analyzer was used to measure RFR at the school surrounding. Buccal mucosa cells from the oral cavity were sampled to examine the level of micronuclei (MN) frequencies. Results: This study found that the densities of the RFR energy differed in range. Although all measurements showed the RFR reading below the acceptable exposure level, there were still significant variations at each location assessed. Statistically, the MN frequency is significantly different when compared to the exposed and non-exposed group. Conclusion: To understand the mechanism of health effects from exposure to low-level RFR emited from MBS, further study should consider environmental factors influencing MBS sitting on RFR emission, as well as examining the health effects into molecular levels.

Nuclear abnormalities in cells from nasal epithelium: a promising assay to evaluate DNA damage related to air pollution in infants / Anormalidades nucleares em células do epitélio nasal: uma técnica promissora para avaliar dano no DNA relacionado à poluição atmosférica em neonatos

OBJECTIVES: This study intends to provide a quick, easy, and inexpensive way to assess nuclear abnormalities such as micronuclei and bud frequencies; binucleated, karyorrhectic, karyolytic, pycnotic, and condensed chromatin cells in nasal scrapings of infants, which are particularly important for conducting genotoxic studies related to the inhaled atmosphere in pediatric populations. METHODS: Nasal swab samples were collected from 40 infants under 12 months of age using a small cytobrush. 2,000 cells from each infant sample were analyzed and classified according to the frequency of nuclear abnormalities. RESULTS: Rates of nuclear abnormalities found agree with values reported in other studies of neonates and children. This study found 0.13% of cells with micronuclei; 1.20% karyorrhexis; 0.03% pyknosis; 10.85% karyolysis; 1.11% condensed chromatin; 0.54 binucleated cells; and 0.02% nuclear bud. Differences were not observed between genders or environmental passive smoking, nor was any age correlation found. CONCLUSION: The assay proposed here is suitable for assessing the frequency of nuclear abnormalities from nasal cells in infants. .

OBJETIVOS: Este estudo pretendeu fornecer uma forma rápida, fácil e barata de avaliar anormalidades nucleares, como frequências de micronúcleos e gêmea, células binucleadas, cariorréticas, cariolíticas, picnóticas e com cromatina condensada, em esfregados nasais de neonatos, o que é particularmente importante para a realização de estudos genotóxicos relacionados ao ar inalado nas populações pediátricas. MÉTODOS: Foram coletadas amostras de esfregaço nasal de 40 neonatos com menos de 12 meses de idade, utilizando uma pequena escova citológica. Foram analisadas 2.000 células da amostra de cada neonato e classificadas de acordo com a frequência de anormalidades nucleares. RESULTADOS: As taxas de anormalidades nucleares encontradas neste estudo são compatíveis com os valores relatados em outros estudos de neonatos e crianças. Encontramos 0,13% de células com micronúcleos, 1,20% com cariorrexe, 0,03% com picnose, 10,85% com cariólise, 1,11% com cromatina condensada, 0,54 com células binucleadas e 0,02% com células nucleares gêmeas. Não observamos diferenças entre os gêneros, tabagismo passivo e nenhuma correlação entre idades. CONCLUSÃO: O ensaio proposto neste estudo é adequado para avaliar a frequência de anormalidades nucleares de células nasais em neonatos. .

Studies of micronuclei and other nuclear abnormalities in red blood cells of Colossoma macropomum exposed to methylmercury

The frequencies of micronuclei (MN) and morphological nuclear abnormalities (NA) in erythrocytes in the peripheral blood of tambaqui (Colossoma macropomum), treated with 2 mg.L-1 methylmercury (MeHg), were analyzed. Two groups (nine specimens in each) were exposed to MeHg for different periods (group A - 24 h; group B - 120 h). A third group served as negative control (group C, untreated; n = 9). Although, when compared to the control group there were no significant differences in MN frequency in the treated groups, for NA, the differences between the frequencies of group B (treated for 120 h) and the control group were extremely significant (p < 0.02), thus demonstrating the potentially adverse effects of MeHg on C. macropomum erythrocytes after prolonged exposure.

Protective effect of lycopene against mercury-induced cytotoxicity in albino mice : Pathological evaluation.

The present study was carried out to evaluate the protective role of lycopene on cytotoxicity induced by mercury in albino mice. The animals were randomly divided into seven groups. Group I (control) were treated with tap water, Group II (positive control) were treated with 20 mg kg-1 d-1 lycopene, Group III were treated with 10 mg kg-1 body weight mercury, Group IV were treated with 10 mg kg-1 body weight mercury + 5 mg kg-1 d-1 lycopene, Group V were treated with 10 mg kg-1 body weight mercury + 10 mg kg-1 d-1 lycopene, Group VI were treated with 10 mg kg-1 body weight mercury + 15 mg kg-1 d-1 lycopene, Group VII were treated with 10 mg kg-1 body weight mercury + 20 mg kg-1 d-1 lycopene once a day for 20 consecutive days by oral gavage. The initial and final weights of all mice were measured by sensitive balance in order to investigate the effect of mercury and lycopene on the body weight of mice. Then, MN slides were prepared using the standard MN assay technique with Giemsa staining from erythrocyte cells of each mouse and were scored using binocular light microscope (Japan, Olympus BX 51). The results indicated that, all lycopene-supplemented lymphocytes showed a lower MN frequency than lymphocytes in only mercury-treated group. It was seen that lycopene had protective effect on MN particularly at 20 mg kg-1 d-1 dose when compared with the other doses. Besides, weight gain increased depending on dose of applied lycopene when compared with only mercury-treated group. In histopathological examinations, although it has been observed severe changes such as hemorrhage, hepatocyte degeneration and tubular degeneration of kidney in only mercury-treated group, there was an observable regression on the severity and account of these lesions in tissues of mice supplemented with different doses of lycopene. In vivo results showed that the lycopene supplementation decreases cytotoxicity induced by mercury and its protective role is dose-dependent.

Development of a Noble Dosimetry Using Metaphase Analysis and Micronuclei Assay of Bone Marrow Cells in Mice / 대한핵의학회잡지

PURPOSE: The purpose of this study was to develop in vivo dosimetries using both chromosomal aberrations and micronuclei in mice to assess biological effects of radiations. MATERIALS AND METHODS: Five each mice were irradiated with 0, 1, 2, 3, 4, 5, 10 Gy of Cs-137 gamma-rays. We scored numbers of chromosomal aberrations in metaphase spreads and numbers of micronuclei in bone marrow smears under light microscope, and obtained the dose-response relationships. We also examined the relationship between the two dose-response curves. RESULTS: The frequency of both chromosomal aberrations and micronuclei increased with dose, in a linear-quadratic manner. The delta, beta, and alpha coefficients were 0.0176, 0.0324, and 0.0567 for metaphase analysis (r=1.0, p<0.001) and 0.0019, 0.0073, and 0.0506 for micronuclei assay (r=1.0, p<0.001). The frequency of chromosomal aberrations and micronuclei in diffirent radiation doses was significantly correlated (r=0.99, p<0.01). CONCLUSION: In vivo dosimetry using either metaphase analysis or micronucleus assay was feasible in mice. These methods could be useful to evaluate biological effects of radiation.