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MN Frequency (mn + frequency)
Selected AbstractsEvaluation of river water genotoxicity using the piscine micronucleus testENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 6 2007Serap Ergene Abstract The Berdan River, which empties into the Mediterranean Sea on the east coast of Turkey, receives discharges of industrial and municipal waste. In the present study, the in vivo piscine micronucleus (MN) test was used to evaluate the genotoxicity of water samples collected from different locations along the Berdan River. Nile tilapia (Oreochromis niloticus) were exposed in the laboratory for 2, 4, and 6 days, and micronuclei were evaluated in peripheral blood erythrocytes, gill cells, and caudal fin epithelial cells. A single dose of 5 mg/L cyclophosphamide was used as a positive control. In addition to micronuclei, nuclear abnormalities (NAs), such as binucleated cells and blebbed, notched, and lobed nuclei, were assessed in the erythrocytes, and chemical analyses were carried out to determine the amount of heavy metals in the water samples. MN and NA frequencies were significantly elevated (up to 2- to 3-fold) in fish exposed to river water samples taken downstream of potential discharges, and the elevated responses in gill and fin cells were related to the concentration of heavy metals in the water. MN frequencies (expressed as micronucleated cells/1,000 cells), in both treated and untreated fish, were greatest in gill cells (range: 0.80,3.70), and generally lower in erythrocytes (range: 0.50,2.80), and fin cells (range: 0.45,1.70). The results of this study indicate that the Berdan River is contaminated with genotoxic pollutants and that the genotoxicity is related to the discharge of wastes into the river water. Environ. Mol. Mutagen., 2007. © 2007 Wiley-Liss, Inc. [source] Effects of dietary boron on cervical cytopathology and on micronucleus frequency in exfoliated buccal cellsENVIRONMENTAL TOXICOLOGY, Issue 1 2007Mehmet Korkmaz Abstract Recent evidence indicates that boron and borates may have anticarcinogenic properties. In this study, we have investigated the incidence of adverse cytological findings in cervical smears and the micronucleus (MN) frequency in women living in boron-rich and boron-poor regions. Cervical smears were prepared from 1059 women with low socioeconomic status; 472 of the women lived in relatively boron-rich rural areas, while 587 lived in relatively boron-poor regions. The average and standard deviation values for the age of the women screened with the cervical Pap smear test were 41.55 ± 8.38. The mean dietary intake of boron was 8.41 mg/day for women from the boron-rich regions, and 1.26 mg/day for women living in the boron-poor regions (P < 0.0001). Women from the boron-rich regions had no cytopathological indications of cervical cancer, while there were cytopathological findings for 15 women from the boron-poor areas (,2 = 10.473, P < 0.05). Sixty women, 30 from each region, were chosen for evaluating MN frequencies in exfoliated buccal cells. MN frequencies for women from the boron-rich and boron-poor regions were not significantly different (t = ,0.294, P > 0.05). Also, there were no significant correlations between age and MN frequency for women from both the boron-rich (r = 0.133, P = 0.48, P > 0.05) and boron-poor (r = ,0.033, P = 0.861, P > 0.05) regions. The results suggest that ingestion of boron in the drinking water decreases the incidence of cervical cancer-related histopathological findings. There was no correlation between the pathological findings from the cervical smears and buccal cell MN frequency suggesting that the two study populations were exposed equally to gentotoxic agents. Nonetheless, cervical cancer-related histopathological findings should be validated by other researchers. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 17,25, 2007. [source] Analysis of micronuclei in blue mussels and fish from the Baltic and North SeasENVIRONMENTAL TOXICOLOGY, Issue 4 2004Janina Bar Abstract Micronuclei (MN) were analyzed in erythrocytes of flounder (Platichthys flesus) and wrasse (Symphodus melops) and in gill cells of blue mussels (Mytilus edulis). The organisms were collected from three study stations in the Baltic Sea and from seven stations in the North Sea (Karmsund area, Norway) 4 times. The statistically significant differences obtained were related to the season, sex of the fish, and sampling locality. Higher MN frequencies were found in fish and mussels collected from the most polluted study stations in the North Sea. The same tendency could be described in the Baltic Sea; however, it was masked by the recent oil spill from the Butinge oil terminal. Our results showing higher MN frequencies in presumably what were the most polluted study locations suggest that MN tests in fish and mussels may be used for the detection of genotoxic effects in a marine environment. The endpoint is well characterized and can be easily recognized, and the technique is convenient to use in field samplings following standard procedures and protocols. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 365,371, 2004. [source] Sister chromatid exchange and micronucleus studies in patients with Behçet's diseaseJOURNAL OF CUTANEOUS PATHOLOGY, Issue 8 2009Ali Karaman Background:, Genetic factors that predispose individuals to Behçet's disease (BD) are considered to play important roles in the development of the disease. The aim of this study was to determine, by counting sister chromatid exchange (SCE) and micronucleus (MN) frequencies, whether DNA damage have an effect on the pathogenesis of BD. Furthermore, our aim was to show if there is an association between oxidative stress and chromosome instability in BD. Methods:, We analyzed lymphocytes from patients with BD (16 in active and 14 in inactive periods) and 20 healthy controls for SCE and MN frequencies. In addition, malondialdehyde (MDA) level, superoxide dismutase (SOD) level, glutathione peroxidase (GSH-Px) activity, erythrocyte sedimentation rate (ESR) and polymorphonuclear leukocyte (PMNL) count were determined in the all subjects. Results:, The SCE and MN frequencies were significantly higher in both the active and inactive period patients than in the controls (p < 0.00001, p < 0.0001, p < 0.01 and p < 0.05, respectively), and the MDA level was significantly higher in both the active and inactive period patients than in the controls (p < 0.01 and p < 0.05, respectively). In contrast, the SOD and GSH-Px levels were significantly lower in both the active and inactive period patients than in the controls (p < 0.01, p < 0.05, p < 0.01 and p < 0.05, respectively). Conclusions:, Our results suggest that increased plasma MDA level and decreased plasma GSH-Px and SOD levels reflect the increased levels of oxidative stress in BD patients, and this situation may impair genetic stability in BD patients. [source] Cytogenetic damage in female Chilean agricultural workers exposed to mixtures of pesticidesENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2005Carolina Márquez Abstract The VIII Region of Bío-Bío is a major fruit-growing area of Chile that makes intensive use of agricultural pesticides. The cytogenetic damage associated with exposure to mixtures of pesticides was evaluated by comparing peripheral blood lymphocyte micronucleus (MN) frequencies in a group of 64 female agricultural workers and 30 female controls. The exposed subjects worked during the spring and summer in thinning and pruning fruit trees and in harvesting and packing different fruits, such as raspberries, grapes, apples, and kiwis. They did not use any protective measures during their work activities. A significant increase in the frequency of binucleated cells with micronuclei (BNMN) was found in the exposed women as compared with the controls (36.94 ± 14.47 vs. 9.93 ± 6.17 BNMN/1000 BN cells; P < 0.001). The frequency of BNMN varied as a function of age in both the exposed and control groups, but no correlation was found between BNMN frequency and the duration of exposure. Also, smoking and other habits had no effect on MN frequency. Our study confirms that occupational exposure to pesticide mixtures results in cytogenetic damage. Environ. Mol. Mutagen., 2005. © 2004 Wiley-Liss, Inc. [source] Effects of dietary boron on cervical cytopathology and on micronucleus frequency in exfoliated buccal cellsENVIRONMENTAL TOXICOLOGY, Issue 1 2007Mehmet Korkmaz Abstract Recent evidence indicates that boron and borates may have anticarcinogenic properties. In this study, we have investigated the incidence of adverse cytological findings in cervical smears and the micronucleus (MN) frequency in women living in boron-rich and boron-poor regions. Cervical smears were prepared from 1059 women with low socioeconomic status; 472 of the women lived in relatively boron-rich rural areas, while 587 lived in relatively boron-poor regions. The average and standard deviation values for the age of the women screened with the cervical Pap smear test were 41.55 ± 8.38. The mean dietary intake of boron was 8.41 mg/day for women from the boron-rich regions, and 1.26 mg/day for women living in the boron-poor regions (P < 0.0001). Women from the boron-rich regions had no cytopathological indications of cervical cancer, while there were cytopathological findings for 15 women from the boron-poor areas (,2 = 10.473, P < 0.05). Sixty women, 30 from each region, were chosen for evaluating MN frequencies in exfoliated buccal cells. MN frequencies for women from the boron-rich and boron-poor regions were not significantly different (t = ,0.294, P > 0.05). Also, there were no significant correlations between age and MN frequency for women from both the boron-rich (r = 0.133, P = 0.48, P > 0.05) and boron-poor (r = ,0.033, P = 0.861, P > 0.05) regions. The results suggest that ingestion of boron in the drinking water decreases the incidence of cervical cancer-related histopathological findings. There was no correlation between the pathological findings from the cervical smears and buccal cell MN frequency suggesting that the two study populations were exposed equally to gentotoxic agents. Nonetheless, cervical cancer-related histopathological findings should be validated by other researchers. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 17,25, 2007. [source] Investigation of histopathological and cytogenetic effects on Lepomis gibbosus (Pisces: Perciformes) in the Çine stream (Ayd,n/Turkey) with determination of water pollutionENVIRONMENTAL TOXICOLOGY, Issue 6 2005Yücel Ba, lu Koca Abstract Water quality and the distribution of some heavy metals in three different organs of Lepomis gibbosus from the Çine Stream were studied. Also, histopathological changes in gill, liver, and muscle tissue were examined at light microscopical level. Micronucleus (MN) formation in fish erytrocytes, as an indicator of chromosomal damage, has been increasingly used to detect the genotoxic potential of environmental contaminants. The frequency of MN was examined from samples of fish from the Çine Stream and a control group. MN frequency was higher in fish samples caught from the Çine Stream than that in the control group. The chemicals ammonia, nitrite, nitrate, orthophosphate, and sulphate were determined as parameters that possibly affect the gill, liver, and muscle morphology. Zn was the most accumulated metal in tissues as well as in water. Maximum metal accumulation occured in both liver and gills. For histopathological examinations, samples of gills, liver, and muscle tissues of L. gibbosus were studied by using light microscopy. In this study, a significant decrease in mean length of primary and secondary lamellae were observed. Moreover, cellular proliferation developed with secondary lamellae fusion, ballooning degenerations or club deformation of secondary lamellae, as well as distribution of necrotic, hyperplastic and clavate secondary lamellae. In the liver, altered staining, swollen and ruptured parenchymal cells, loss of cord structure, reduce of glycogen in hepatocytes, and vacuolar structure filled with cellular debris and many dark particles were seen. In muscle tissue, focal necrosis, cellular dissolution, and a decline or loss of striatation in muscle fibres were found. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 560,571, 2005. [source] Subchronic exposure of BALB/c and C57BL/6 strains of Mus musculus to the radioactive environment of the Chornobyl, Ukraine exclusion zoneENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2001Brenda E. Rodgers Abstract Environmental contamination resulting from the Chornobyl, Ukraine, disaster offers a unique opportunity to examine the in vivo biological effects of chronic, low-dose exposure to radiation. Laboratory studies of acute exposure to ionizing radiation have been used to estimate risk and potential human health effects by the extrapolation of laboratory data to situations of low-dose environmental radiation exposure. Few studies, however, have explored the biological consequences of low-dose exposure via in situ environmental radiation in a sentinel species. In the present study, laboratory strains of Mus musculus (BALB/c and 57BL/ 6) were placed in environmental enclosures in the Red Forest region of the Chornobyl exclusion zone. Blood samples were obtained every 10 d, and the micronucleus (MN) test was employed to assess the potential for cytogenetic damage from exposure to Chornobyl radiation. Radionuclide uptake was monitored throughout the study, and dose was estimated for each individual as well as for their offspring. Total dose for the mice experimentally exposed to this environment averaged 1162 mGy for BALB/c (30 d) and 1629 mGy for C57BL/6 (40 d). A higher MN frequency for both strains was observed at day 10, although this change was only statistically significant in the C57BL/6 mice (,23 = 13.41, p = 0.003). Subsequent samples from C57BL/6 resulted in values at or less than the initial frequencies. In BALB/c mice, an increase in MN was also evident at day 30 (,22 = 10.38, p = 0.006). The experimental design employed here allows for the incorporation of traditional laboratory strains, as well as transgenic strains of Mus, as sentinels of environmental radiation contamination. [source] Cytotoxicity and genotoxicity of sodium percarbonate: a comparison with bleaching agents commonly used in discoloured pulpless teethINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2010M. R. Fernández Fernández MR, Carvalho RV, Ogliari FA, Beira FA, Etges A, Bueno M. Cytotoxicity and genotoxicity of sodium percarbonate: a comparison with bleaching agents commonly used in discoloured pulpless teeth. International Endodontic Journal, 43, 102,108, 2010. Abstract Aim, To evaluate the cytotoxicity and genotoxicity of sodium percarbonate (SPC) in comparison with bleaching agents used on discoloured pulpless teeth. Methodology, The cytotoxicity and genotoxicity of bleaching agents were evaluated both in their pure form as well as at concentrations commonly used in clinical practice. Hydrogen peroxide (HP), carbamide peroxide (CP), sodium perborate (SP) and SPC were diluted in Dulbecco's modified Eagle's medium (DMEM) in series. To evaluate the cytotoxicity, the survival of 3T3/NIH mouse fibroblasts was measured photometrically using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after a 24 h-exposure period. Genotoxicity was indicated by micronuclei (MN) formation, and modification of the normal cell was analysed by light microscopy (400×). Statistical analysis was performed by one-way anova, followed by a multiple-comparison Tukey post hoc test (P < 0.05). Results, All groups exhibited a dose-dependent cytotoxicity. However, CP showed a similar cytotoxic effect when compared with DMEM-untreated control (UC) group. HP and SPC were significantly more cytotoxic than SP. The genotoxicity test showed that SPC and SP had an intermediate rate of MN frequency when compared with the UC group. The mean rate of MN frequency for HP was higher and statistically more significant than for the other groups tested. No difference was observed when CP and UC groups were compared. Conclusions, Sodium percarbonate showed cytotoxicity and genotoxicity similar to those of the other products tested. However, before SPC is used clinically, studies should be conducted to confirm its safety in vivo. [source] Genotoxicity study in lymphocytes of offset printing workersJOURNAL OF APPLIED TOXICOLOGY, Issue 1 2006Hüseyin Aksoy Abstract The potential cytogenetic damage in offset printing workers was evaluated using sister chromatid exchanges (SCEs), chromosome aberrations (CAs) and micronuclei (MN) as biomarkers in peripheral lymphocytes of 26 volunteers (14 workers, 12 controls). The CA, SCE and MN frequency of offset printing workers was significantly higher than in their controls. The replication index (RI) was not affected while the mitotic index (MI) was affected most in the workers. It can be concluded from this study that chronic occupational exposure to printing dyes and thinner may lead to a slightly increased risk of genetic damage among offset printing workers. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||