室内常见气传真菌代谢提取物的遗传毒性研究

目的 探讨室内常见气传真菌代谢提取物的致突变性。方法 分别采用以基因突变为测试终点的Ames试验、以DNA损伤为UDS试验及染色体损伤为终点的体外细胞微核试验,对其进行了系统研究。结果 Ames试验结果显示部分室内气传真菌代谢提取物是一种间接致突变物质,UDS试验结果表明其具有DNA损伤作用,体外细胞微核试验显示其具有染色体损失作用。结论 部分室内常见气传真菌代谢提取物具有一定的遗传毒性。     

SQA鳌合盐的急性毒性和致突变性研究

目的 检测稀土壳糖胺(SQA)鳌合盐的急性毒性和致突变性。方法 采用霍恩氏法进行急性经口毒性试验，采用小鼠骨髓嗜多染红细胞微核试验、小鼠精子畸形试验和Ames试验对受试物进行致突变性研究。结果 SQA鳌合盐的经口LD50＞10000mg／kg体重；小鼠骨髓嗜多染红细胞微核试验显示无诱发微核作用，小鼠精子畸形试验未见精于畸形率增高，Ames试验在加和不加S9条件下均无致突变性。结论 SQA鳌合盐属实际无毒级物质，在该实验条件下，无致突变作用。     

盐酸关附乙素致突变作用的研究

采用小鼠精子畸变试验、小鼠骨髓细胞染色体畸变试验、小鼠骨髓嗜多染红细胞微核试验和Ames试验,检测盐酸关附乙素的致突变性.实验结果:该药物未引起小鼠骨髓嗜多染红细胞微核率、小鼠精子畸变率和小鼠骨髓细胞染色体畸变率的增加.与阴性对照组差异无显著性;Ames试验为阴性.提示该药物无致突变性.     

宣威县肺癌高发区室内空气不同粒径颗粒物的致突变性与致癌性

我们采用Ames试验和中国地鼠卵巢细胞(CHO细胞)姐妹染色单体交换(SCE)测试系统对宜威县肺癌高发区室内空气中不同粒径颗粒物进行了致突性研究。采用二阶段皮肤致癌试验测定其致癌性。结果表明:各粒径颗粒物均有致突变性和致癌性,颗粒物粒径越小其致突变性和致癌性越强。     

饮用水中二溴乙酸遗传毒性研究

二溴乙酸 (DBA)是饮用水氯化消毒副产物中的一种 ,属于氯乙酸类 ,臭氧消毒也可产生。本次试验采用Ames试验、程序外DNA合成 (UDS)试验、小鼠体内微核试验、NIH3T3细胞微核试验对其遗传毒性进行了研究。在Ames试验中 ,TA10 0菌株在加与不加S9的情况下均表现出致突变性。在大鼠肝细胞UDS试验中 ,DBA表现出明显的DNA损伤作用 ,导致程序外合成增加。在小鼠体内微核试验中 ,DBA在一定剂量范围内可引起染色体损伤。在NIH3T3细胞微核试验中 ,DBA可诱导细胞微核数增加。上述结果表示 ,DBA具有明确的DNA损伤作用。     

用3种方法检测Q流域地面水致突变活性

目的 为了调查Q流域地面水致突变性。方法 用Ames试验、胞质阻断微核试验(CBMN)及彗星试验(comet assay)检验Q流域地面水14个地面水样品的致突变作用。结果 Ames试验结果表明9个样品对TA98(±S9)有致突变作用。4个样品对 TA100(-S9)有致突变作用,2个样品对TA100(+S9)有致突变作用。选择5个对TA98有致突变作用的样品及1个无致突变作用的样品,用胞质阻断微核试验及彗星试验进行检测,结果表明5个典型的对TA98有致突变作用的样品有5个可引起微核细胞率增加和细胞DNA迁移增高。而无致突变作用的样品后2项试验均为阴性。在3项短期试验中,Ames试验比另2个试验更为灵敏。结论 3个不同遗传终点的诱变试验均发现Q流域地面水部分样品具有致突变性。     

β-1，3-D-葡聚糖的遗传毒性研究

目的 检测β-1，3-D-葡聚糖的遗传毒性。方法 采用Ames试验、小鼠骨髓嗜多染红细胞微核试验和小鼠精子畸形试验对受试物进行遗传毒性研究。结果 β-1，3-D-葡聚糖Ames试验在加和不加S9条件下均无致突变性，对小鼠骨髓嗜多染红细胞微核试验无诱发微核作用，小鼠精子畸形试验未见精子畸形率增高。结论 β-1，3-D-葡聚糖在本实验条件下，无致突变作用。     

溴硝醇的致突变作用

目的研究常用化学添加抗菌剂溴硝醇的致突变性。方法通过CHL细胞染色体畸变试验、CHO细胞正向基因突变试验、Ames试验及小鼠骨髓微核试验等4个致突变生物学试验对溴硝醇进行致突变性研究。细胞染色体畸变试验,选用CHL细胞,设暴露浓度为30、10、5、2.5mg/L(-S9)和50、20、10、3mg/L(+S9)。正向基因突变试验,选用CHO细胞,设暴露浓度为20、10、5、2.5mg/L。Ames试验,选用TA97、TA98、TA100、TA102、TA1535菌株,暴露浓度为50、25、12.5、6.25、3.125μg/皿(+S9),30、15、7.5、3.75、1.875μg/皿(-S9)。小鼠骨髓微核试验,60只小鼠随机分成6组,雌雄各半,雄性小鼠染毒剂量为20、40、80mg/kg;雌性小鼠为25、50、100mg/kg。结果 CHL细胞染色体畸变试验结果显示,各剂量组溴硝醇诱发的染色体畸变率均≤4.5%,与阴性对照组比较差异无统计学意义(P0.05)。正向基因突变试验结果显示,各剂量组溴硝醇对CHO细胞突变频率,与阴性对照比较差异无统计学意义(P0.05)。Ames试验结果显示,各剂量组溴硝醇的回变菌落数均阴性对照组的自发回变菌落数的2倍,亦无剂量反应关系。小鼠骨髓微核试验结果显示,溴硝醇3个剂量组均未引起微核出现率增加。结论本研究条件下,溴硝醇无明显致突变作用。     

氟化钠对果蝇伴性隐性致死试验研究

氟(Fluoride)是人体必需的微量原素,但摄入过量又可引起中毒。人体摄入氟的主要来源是饮水和食物,尤以饮水更重要,氟中毒与饮用水中氟的含量有着密切关系,目前对饮水中加氟的争论很大,氟最高允许浓度问题世界末有统一标准,仍是研究的重要课题。近年来本实验室对氟化钠进行微核试验,SCE,Ames 致突变试验和大白鼠致畸胎研究没有显示出诱变性和致畸性。多年来,国内外许多学者对氟在致突变方面的研究有了许多报道。但用果蝇伴性隐性致死(SLRL)试验对氟进行致突变研究报道尚少。为此     

二氯甲烷的致突变性研究

本文采用Ames试验,姊妹染色单体互换试验,小鼠微核试验,小鼠精子畸形试验对二氯甲烷(CH_2Cl_2)的致突变性进行研究。实验结果表明、其在空气中浓度为48000-120000mg/M~3时对试验菌株TA98,TA100具有诱变作用,在培养液中二氯甲烷的浓度为0.4258—42.58mg/ml时能诱发人体外周血淋巴细胞SCE频率明显增加(P<0.001),但未见二氯甲烷对小鼠骨髓嗜多染红细胞微核率,小鼠精子畸形率有明显影响。本研究结果在体外试验为阳性,体内试验为阴性可能由于体内外酶系统,和/或测试遗传学终点差异所致。     

用Ames试验和小鼠原代细胞彗星试验检测A市生活饮用水遗传毒性

目的　用Ames试验和小鼠原代肝细胞彗星试验检测A市生活饮用水遗传毒性并比较两种方法的敏感性。方法　采用Ames试验和彗星试验分别对A市南郊水厂的水源水、出厂水、自来水的有机浓集物的诱变性进行检测。结果　出厂水和自来水的Ames试验于试样浓度为 3 0L/皿时才表现为阳性结果 ,而肝细胞的彗星试验在水样量为0 1L时就出现明显的阳性结果 (与阴性对照比P <0 0 1) ,后者的浓度比前者低 3 0倍。水源水的Ames试验于试样浓度为 6 0L/皿时仍表现为阴性结果 ,而原代肝细胞的彗星试验在水样量为 0 5L时就出现明确的阳性结果。结论　Ames试验只能检测出氯化消毒后饮用水的致突变阳性 ,而彗星试验能同时检测出水源水和氯化消毒后饮用水的致突变性 ,后者的敏感性远远高于前者。     

Single-cell gel electrophoresis (SCG)-A review and discussion

Single-cell gel electrophoresis (SCG) is a simple, sensitive and effective technique. Being able to reflect quantitatively the genotoxicity of many hazardous agents, it is promising for application in environmental genotoxic monitoring and the study of carcinogenesis. In clinics, it can be used to evaluate the DNA repair ability and monitor DNA breaks during cancer therapy. As a biomarker, it has its own merits and limitations, being different from other biomarkers such as sister chromatid exchange (SCE) test and micronuclei (MN) assay. In many studies, it is more sensitive than SCE or MN. Combination studies with other biomarkers like SCE, MN, chromosomal aberration, bcl-2 and genetic polymorphisms have begun to demonstrate its great importance for the understanding of carcinogenesis and the genotoxicities of environmental factors.     

巢湖源水和饮用水的诱变性研究

采用组合致突变性试验对以巢湖水为水源的合肥市四水厂的水源水、沉淀池出水和出厂水有机浓集物的诱变性进行了研究。结果表明巢湖源水及其氯化饮用水，在细菌，真核细胞以至整体动物试验中都呈现一定诱变性。混凝沉淀 工艺可除去部分诱变物。出厂水浓集物的致突变能力最强，其次为水源水，沉淀地出水最弱，多种方法联合应用，提高了饮水中诱变物检测的敏感性。研究还表明四种试验对饮水致突变性的检出敏感性顺序依次为ＳＣＥ＞微核     

Genotoxic properties of municipal wastewaters in Ohio

Wastewaters from six municipal wastewater treatment plants in Ohio were tested at different stages of treatment for mutagenicity in the Ames/Salmonella assay. The chlorinated secondary effluents were also evaluated for induction of sister chromatid exchanges in Chinese hamster ovary cells. Direct-acting microbial mutagenicity was observed for extracts of the effluents from all six plants for both an initial and a repeat sampling series. In some cases, the mutagenicity was greatly enhanced by S9 metabolic activation (MA). In general, the specific mutagenicity of the extracts increased following activated sludge treatment. Chlorination resulted in substantial increases in mutagenic activity for some of the Wastewaters but had no effect on others. SCE inducing activity was detected in five out of six extracts for the first sample series, and for two out of five extracts for the second sample series. There was no obvious correlation in the ability of the extracts from the chlorinated secondary effluents to induce SCE in CHO cells and to induce mutations in Salmonella.     

异佛尔酮二异氰酸酯毒理学研究

经ＧＰＭＴ法检测，２５％异佛尔酮二异氰酸酯（ＩＰＤＩ）对豚鼠的致敏率为５０％，属中等致敏物。ＩＰＤＩ对小鼠脾脏抗体生成细胞有抑制作用，但可刺激豚鼠Ｔ淋巴细胞及淋巴细胞转化功能。Ａｍｅｓ试验阴性，１６６ｍｇ／ｋｇＩＰＤＩ可诱导大鼠骨髓染色体畸变、小鼠骨髓嗜多染红细胞微核率增高、小鼠骨髓细胞ＳＣＥ增加及ＵＤＳ试验阳性。ＩＰＤＩ５３～４２４ｍｇ／Ｌ对小鼠骨髓细胞ＤＮＡ合成有明显抑制作用，表明ＩＰＤＩ对体细胞具有断裂剂活性和损伤ＤＮＡ作用。小鼠精子畸形试验和睾丸染色体畸变试验表明对生殖细胞无明显损伤作用。大鼠致畸试验说明ＩＰＤＩ为不致畸物。职业接触ＩＰＤＩ人群调查表明，接触者有明显的粘膜和呼吸道刺激症状，高浓度接触者肺功能（ＦＶＣ、ＦＥＶ１．０）较对照组有下降趋势，其他心、肝、肾功能、外周血淋巴细胞亚群检查、染色体畸变分析、内科、神经系统检查均与对照组无显著性差异。     

Assessing the genotoxicity of imidacloprid and RH-5849 in human peripheral blood lymphocytes in vitro with comet assay and cytogenetic tests

A combined approach employing comet assay and micronucleus (MN) and sister chromatid exchanges (SCE) tests was utilized to assess the genotoxicity of two pesticides, imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitro-imidazolidin-2-ylideneamine] and RH-5849 [2'-benzoyl-1'-tert-butylbenzoylhydrazine], on human peripheral blood lymphocytes in vitro. No significant difference in the frequencies of MN and SCE from the negative groups (P>0.05) was observed at low dose levels (i.e., 0.05 mg/L for imidacloprid and 5mg/L for RH-5849). As the concentrations of imidacloprid and RH-5849 were increased to 0.1 and 25 mg/L, respectively, significant effects to the frequencies of MN and SCE (P<0.05) were achieved relative to those of the negative controls. MN and SCE frequencies increased similarly in a dose-related manner with both pesticides. With the comet assay, however, the distribution of DNA damage grades in all the pesticide-treated groups was significantly different from those in the control (P<0.01). DNA damage scores increased with the exposure levels of both pesticides, and linear dose-effect relationships were observed for both imidacloprid (r2=0.98) and RH-5849 (r2=0.92). The cytogenetic techniques and comet assay revealed potential adverse effects of both imidacloprid and RH-5849 in human peripheral blood lymphocytes in vitro. Combination of the comet assay and cytogenetic tests appears commendable to assess the potential risks of human exposure to the pesticides.     

不同致癌能力镍化合物的致突变效应

Ni_3S_2,NiSA,NiSC,NiSO_4与NiCl_2等五种镍合物是具有不同致癌能力的化合物。在V_(79)细胞株基因突变试验系统中,这五类化合物能诱发HGPGT 与Na/k ATP ase 酶位点突变,其强弱程度与在动物致癌试验结果所见是一致的。提示这些镍化合物可能是通过致突变机制作用的致癌物。亦可以利用基因突变试验来预测其致癌性。这五种镍化合物可在V_(79)细胞株和SHE 细胞诱发SCE 与微核形成,但其作用强弱与其致癌能力不相一致。表明利用这类试验预测镍化合物的致癌性是不适宜的。     

Assessment of occupational genotoxic risk in the production of rubber tyres

A broad spectrum of substances is used in the rubber industry, many of them being genotoxic and/or carcinogenic. Convincing evidence of an excess of certain forms of cancer among rubber workers has been provided. The objective of this study was to determine the genotoxic effects in a group of individuals engaged in the production of rubber tyres from a Portuguese factory. Peripheral blood samples were collected from 32 exposed workers and 32 controls, and micronucleus (MN) test, sister chromatid exchanges (SCE) and comet assay were performed. Urinary thioethers were measured as a general biomarker of exposure to electrophilic compounds, and genetic polymorphisms in metabolizing enzymes (CYP2E1 Dra I, EPHX1 codons 113 and 139, GSTP1 codon 105, and GSTM1 and GSTT1 deletion polymorphisms) were analysed as susceptibility biomarkers. Excretion of thioethers was found significantly higher in rubber workers. Also, a non-significant increase in MN frequency related to time of exposure and no effect in SCE were observed in the exposed. Comet assay data showed decreased TL values in the exposed population with respect to the control group, this might indicate the induction of crosslinks by the substances present in the workplace environment. Significant increase in MN frequency was obtained for GSTT1 null exposed individuals with respect to positive ones, and interaction with GSTP1 polymorphism was found. Higher levels of cytogenetic test frequencies were observed in epoxide hydrolase expected low activity donors with respect to medium and high activity individuals. No effect of CYP2E1 or GSTM1 variants was obtained in the biomarkers analysed.     

Long-term monitoring of sister chromatid exchanges and micronucleus frequencies in pharmacy personnel occupationally exposed to cytostatic drugs

Objectives: Many antineoplastic drugs were found to have carcinogenic, mutagenic and teratogenic potential. The aim of this study was to carry out cytogenetic and internal dose monitoring of hospital pharmacy personnel regularly involved in the preparation of cytostatic agents, in order to test possible cytostatics-induced genotoxic effects due to occupational exposure under routine working conditions, and in cases of accidental contamination. Methods: Platinum in whole blood and anthracyclines in plasma were measured to assess internal exposure to cytostatics. The level of cytogenetic damage was determined in peripheral blood lymphocytes with the micronucleus test and the sister chromatid exchange assay. Five series of monitoring were performed over a period of 2 years. Results: No significant differences in the mean frequencies of sister chromatid exchanges (SCE) and micronuclei (MN) were found between occupationally exposed probands and controls (9.9 ± 1.4 vs 10.1 ± 1.2 SCEs/cell and 21.2 ± 7.2 vs 23.3 ± 7.5 MN/2000 binucleated (BN) cells, n=16). Significant elevations of SCE or MN were detected in seven out of 12 cases of accidental contamination at the workplace, whereas no increase in platinum in blood and anthracyclines in plasma was observed in these probands. Two cases of non-reported contamination were identified by measurement of epirubicin in plasma. Smoking was found to increase the SCE significantly. No correlation between individual SCE scores and MN scores was observed. Conclusions: Our findings support a transient increase in SCE or MN after relevant exposure to cytostatic drugs in cases of accidental contamination. The lack of significant differences in SCE and MN between hospital pharmacy personnel and unexposed controls, points to high standards of safety at the corresponding workplaces. Received: 11 October 1999 / Accepted: 25 April 2000     

Absence of mutagenic response to radiation from a video display terminal

The standard Ames Salmonella test (TA 100) was used to detect the mutagenicity of radiation from a video display terminal. The Ames test is a sensitive assay that detects the ability of a chemical to damage deoxyribonucleic acid. It has also been employed to detect the mutagenicity of electromagnetic radiation. An extremely short distance (62 mm) from a video display terminal and an extremely high electrostatic field strength (250 kv/m) was employed. No mutagenic response was found in this test system.