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101.
《Acta odontologica Scandinavica》2013,71(3):219-227
AbstractObjective. This study aimed to evaluate the occurrence of chromosomal abnormalities, through micronuclei, and apoptosis by the sum of karyorrhexis, pyknosis and condensed chromatin in individuals with chronic periodontitis, gingivitis associated with biofilm and no periodontal disease. Materials and methods. This study included 72 individuals divided into three groups: gingivitis (n = 21), periodontitis (n = 24) and control (n = 27). Information on sociodemographic characteristics, health and lifestyle was obtained. Full mouth clinical examination was performed to define the periodontal condition. Exfoliated cells from gingival mucosa were collected for computation of micronuclei and nuclear changes indicative of apoptosis. The differences in the occurrence of endpoints (micronucleus, karyorrhexis, pyknosis and condensed chromatin) were evaluated using the conditional test to compare proportions in a rare events situation. Results. There was no statistically significant difference in the occurrence of micronucleus (p > 0.1) between gingivitis, periodontitis and control groups. The occurrence of apoptosis was significantly higher among individuals with periodontitis compared to individuals with gingivitis (p < 0.05) and controls (p < 0.025). Conclusions. The findings showed that the inflammatory process generated by gingivitis and periodontitis is not related to a higher occurrence of chromosomal damage. However, the higher occurrence of apoptosis in individuals with periodontitis points to genotoxic effects induced by periodontal infection. 相似文献
102.
H Donmez-Altuntas† Z Sut† A Ferahbas‡ Z Hamurcu§ H Demirtas† 《Journal of the European Academy of Dermatology and Venereology》2008,22(2):162-167
Background Vitiligo is a relatively common, acquired pigmentary disorder characterized by areas of depigmented skin resulting from loss of melanocytes in the epidermis. Although several hypotheses have been proposed for the aetiology and pathogenesis of vitiligo, the cause of vitiligo remains unclear. Objective To evaluate spontaneous micronucleus (MN) frequency using the cytokinesis block MN assay to determine damages at the DNA or chromosome level in phytohaemagglutinin (PHA)‐stimulated blood cells of patients with vitiligo and healthy control subjects. Methods Peripheral blood samples were obtained and cultured from 21 patients with vitiligo (mean age: 21.48 ± 9.78 years) and 21 age‐ and sex‐matched healthy control subjects (mean age: 21.52 ± 9.80 years). MN values were scored in binucleated cells obtained from whole‐blood cultures of patients and control subjects. Results MN frequencies (mean ± SD) in PHA‐stimulated blood cells of patients with vitiligo and control subjects were 0.94 ± 0.58 and 0.58 ± 0.32, respectively. Compared with control subjects, MN frequencies of patients with vitiligo were found significantly higher than those of the control subjects (P = 0.012). Conclusion Our results indicate unexpectedly some chromosomal/DNA damage in whole‐blood cultures of patients with vitiligo. We do not know, however, if these chromosome/DNA instabilities observed in the cells of vitiligo patients resulted from the cause or from the consequences of the disorder. 相似文献
103.
104.
采用人体外周血淋巴细胞染色体畸变和微核两项试验对沥青接触者进行细胞遗传学效应研究,结果表明,染色体畸变率和微核检出率接触者均比非接触者高,经泊松检验P<0.01,差异有非常显著意义,说明沥青可导致染色体损伤。但48例的染色体与微核检测的配对卡方检验,X~2=7.84,P<0.01,说明微核检测方法不及染色体检测灵敏。本文还对吸烟者和不吸烟者的染色体畸变分析进行了比较,结果表明,不论在接触组和非接触组中差异均无显著性意义,P>0.05。 相似文献
105.
Judith Jimnez Leticia Rivern-Negrete Fikrat Abdullaev Javier Espinosa-Aguirre Rosario Rodríguez-Arnaiz 《Experimental and toxicologic pathology》2008,60(4-5):381-389
beta-Carboline alkaloids are natural products widely distributed in plants and also found in alcoholic beverages, well-cooked foods and tobacco smoke. Various authors have reported genotoxic activities of several carboline in prokaryotic and eukaryotic cells that have been attributed to their abilities to intercalate into DNA. But studies on the genotoxic and on the cytotoxic potencies in human cells in vitro are not found in the literature. In the present study the toxicities of one full aromatic beta-carboline alkaloid (harmine) and one dihydro-beta-carboline alkaloid (harmaline) were evaluated by means of two in vitro human cell assays: the cytochalasin-B blocked micronucleus (CBMN) assay and the viability/colony formation assay with four different human cultured non-transformed (CCD18Lu) and transformed (HeLa, C33A and SW480) cells. Neither alkaloid was able to induce micronuclei levels above that of control levels in a wide range of doses tested; although, harmine at the highest concentrations assayed induced apoptotic as well as necrotic cells. Harmine produced a good viability of all cell lines assayed (control and tumor) while harmaline significantly reduced the viability of transformed and non-transformed cell lines in a dose-dependent manner. Harmine displayed a dose-dependent inhibitory effect on cell proliferation against all human carcinoma cells, but the SW480 transformed cell line showed a higher sensitivity. These results suggested that harmine was identified as a useful inhibitor of tumor development. 相似文献
106.
The increment of micronucleus frequency in cervical carcinoma during irradiation in vivo and its prognostic value for tumour radiocurability. 总被引:6,自引:0,他引:6
M Widel S J?dru? S Owczarek M Konopacka B Lubecka Z Ko?osza 《British journal of cancer》1999,80(10):1599-1607
A potential usefulness of micronucleus assay for prediction of tumour radiosensitivity has been tested in 64 patients with advanced stage (II B-IV B) cervical carcinoma treated by radiotherapy. The study of cellular radiosensitivity in vitro was conducted in parallel with the study of cellular damage after tumour irradiation in vivo. Radiosensitivity of in vitro cultured primary cells isolated from tumour biopsies taken before radiotherapy was evaluated using cytokinesis-block micronucleus assay. Frequency of micronuclei per binucleated cell (MN/BNC) at 2 Gy was used as a measure of radiosensitivity. Radiation sensitivity in vivo was expressed as per cent increment of micronucleus frequency in cells isolated from biopsy taken after 20 Gy (external irradiation, 10 x 2 Gy) over the pre-treatment spontaneous micronucleus level and was called MN20. Very low correlation (r = 0.324) was observed between micronucleus frequency in vitro and in vivo. Although micronucleus frequency at 2 Gy differed widely between tumours evaluated (mean MN/BNC was 0.224; range 0.08-0.416), no significant correlation was observed between this parameter and clinical outcome. The average increment of micronucleus frequency after 20 Gy amounted to 193% of spontaneous level (range 60-610%) and was independent of spontaneous micronucleation before radiotherapy. In contrast to in vitro results, these from in vivo assay seem to have a predictive value for radiotherapy of cervix cancer. The micronucleus increment in vivo that reached at least 117.5% of pretreatment value (first quartile for MN20 data set) correlated significantly with better tumour local control (P < 0.008) and overall survival (P < 0.045). Our results suggest that evaluation of increment of micronucleus frequency during radiotherapy (after fixed tested dose of 20 Gy) offers a potentially valuable approach to predicting individual radioresponsiveness and may be helpful for individualization of treatment strategy in advanced stage cervical cancer. 相似文献
107.
本文应用医用直线加速器6MV X 线照射5例健康成人离体血研究淋巴细胞微核与剂量间的关系,发现微核率及微核细胞率可各配以回归方程 Y=6.6896×10~(-3)+1.2959×10~(-2)D~2及 Y=7.3906×10~(-3)+1.0824×10~(-2)D~2,其 R~2值分别为O.9948及0.9976,有较好的拟合度,可作为预测受照剂量的模型。 相似文献
108.
细胞微核形成机理探讨 总被引:12,自引:0,他引:12
微核试验是反映染色体损伤,进行遗传毒性评估的重要试验,该文对微核的相关信息进行了分析,并结合自己的研究工作,对微核的形成机理进行了深入探讨。 相似文献
109.
微核试验和彗星试验检测朱砂的遗传毒性 总被引:1,自引:1,他引:0
目的:研究朱砂对大小鼠染色体的损伤作用,比较短期给药与长期给药对遗传毒性检出的影响,探讨结合生殖毒性Ⅰ段试验进行遗传毒性研究的可行性。方法:18只小鼠分3组灌胃给药10,5.02,.5 g.kg-1(分别相当于人临床最高等效剂量约100,50,25倍)朱砂悬浊液,2 d后处死;结合生殖毒性Ⅰ段大鼠(每组6只)连续灌胃给药1.0,0.3,0.1 g.kg-1(分别相当于人临床最高等效剂量的20,6.4,2.0倍),雄性42 d以上,交配成功后处死;雌性20 d以上,妊娠第15天处死,取骨髓细胞做微核试验和彗星试验。结果:小鼠各剂量组灌胃给药的微核率分别为0.175%,0.108%,0.092%,与阴性对照组比较差异有显著意义,但彗星试验结果阴性。结合生殖毒性Ⅰ段试验的微核试验中雄性和雌性大鼠的微核率与阴性对照组比较,差异无显著意义,但有随剂量增高而增高的趋势;而彗星试验结果显示雄性的中、高剂量和雌性的高剂量的拖尾阳性率为27.6%,42.8%,22.3%,与阴性对照组比较,差异有显著和极显著意义。结论:①朱砂短期内大剂量灌胃给药或长期小剂量给药可能引起染色体损伤;②利用生殖毒性Ⅰ段试验多次给药后取材做微核试验和彗星试验在方法上是可行的,在剂量设计上更符合中药长期低剂量给药方式;③微核试验和彗星试验的组合在评价药物的体内遗传毒性中具有互补性。 相似文献
110.
Pículo F Guiraldeli Macedo C de Andrade SF Luis Maistro E 《Journal of applied toxicology : JAT》2011,31(7):633-639
Nerolidol is a sesquiterpenoid component of essential oil used as a flavor and aroma enhancer. It has also been studied as a topical skin penetration enhancer, and has inhibitory activities against S. aureus and E. coli, among other activities. The objective of this study was to evaluate the ability of a single nerolidol treatment to induce DNA damage in peripheral blood and liver cells of mice and micronuclei in polychromatic erythrocytes of bone marrow cells of the same animals. In the dose range‐finding assays, the maximum tolerated dose was higher than 2000 mg kg?1. The doses used in the experiments were 250, 500 and 2000 mg kg?1, administered by gavage in a single dose. Peripheral blood cells were collected 4 and 24 h after the treatments and liver cells 24 h after. At least 100 nucleoids per cell type/animal were analyzed to determine the DNA damage scores and 2000 PCEs per animal for micronuclei in PCEs. The positive control was N‐nitroso‐N‐ethylurea 50 mg kg?1. Cytotoxicity was assessed by scoring 200 consecutive total polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE:NCE ratio). The results showed that nerolidol induced weak levels of dose‐related DNA damage in both types of cells analyzed, and enhanced the average number of micronucleated cells in the two high doses tested. The PCE:NCE ratio showed no cytotoxicity for the three doses of the compound. The data obtained support the view that nerolidol induces clastogenicity and very weak genotoxicity in the mouse cells tested. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献