评价净化饮用水的化学毒性和遗传毒性的新方法

意大利佩鲁贾大(University of Perugia)的学者建立了一种新的评价地表饮用水中化学物的化学毒性和遗传毒性的方法．用于评价用次氯酸钠、二氧化氯和过氧乙酸进行消毒处理的地表饮用水的化学毒性和遗传毒性。他们建立一个试验厂用于连续地向3个容器中未过滤的湖水中加入消毒剂，并进行了短期整体试验(用植物、鱼、软体动物)和体外试验(用细菌、真菌和人类细胞)以评价消毒副产物(disinfection by-products，DBPs)的遗传毒性，     

有机污染物对人肝肿瘤细胞的遗传毒性

目的 用人肝肿瘤细胞HepG2／体外微核试验检测3种持久性有机污染物（POPs）Aroclor1254、毒杀芬和滴滴涕的遗传毒性。方法 人肝肿瘤细胞HepG2经Aroclor1254、毒杀芬和滴滴涕染毒24h，继续在补充细胞松弛素B（3μg/ml）的培养液中培养24h后，计数1000个双核细胞中的微核。结果 20，40μmol／L毒杀芬处理HepG2细胞的微核率与溶剂对照相比显著增加（P〈0.01，P〈0．01）；经Aroclor1254（23～184μmol／L）和滴滴涕（17．8～60μmol／L）处理的HepG2细胞的微核率与溶剂对照相比，差异无统计学意义。结论 Arodor1254和滴滴涕未显示对HepG2细胞明显的遗传毒性；毒杀芬可诱导HepG2细胞遗传损伤，有必要进一步评价其对人类健康的潜在危害。     

基于体外染色体畸变试验评价纳米银敷料遗传毒性的研究

目的:通过体外染色体畸变试验来检测纳米银敷料引起遗传毒性的可能性,为临床前安全性评价提供资料与提示。方法:根据《GB/T16886.3-2008/ISO 1099-3:2014》中推荐的方法选用中国仓鼠肺细胞(CHL)进行体外哺乳动物细胞染色体畸变试验(CAT),在代谢活化系统(+S9)与非代谢活化系统(-S9)条件下,检测纳米银敷料浸提液在+S9/6h、-S9/6h、-S9/24h三种处理条件下诱发CHL细胞的染色体畸变率。结果:纳米银敷料各处理组的染色体畸变率与阴性对照组相比无显著性差异(P>0.05)。在与CHL接触24h后,细胞出现了明显形态改变。结论:在该试验条件下,纳米银敷料浸提液对CHL细胞的染色体无明显损伤作用,在24h接触组中出现了明显的细胞毒性。     

氟化物细胞毒性和遗传毒性的研究进展

目前，研究者对氟化物的细胞毒性已达成共识，但对其遗传毒性尚未定论，争议颇多。参阅了国内外有关文献，对氟的细胞毒性及遗传毒性加以综述。     

非遗传和遗传毒性化学物致癌机理的研究进展

本文就化学物致癌性的共同特点与程序外细胞增生有关的假设做了阐述，并提出无论是具有遗传毒性，还是具有非遗传毒性的化学物，其致癌性不仅取决于细胞增生，还与ＤＮＡ的不确定改变有关这一新观点。     

乙苯遗传毒性的研究概述

乙苯在工业上通过苯与乙烷的烷化工序合成，主要用于苯乙烯的生产。乙苯还作为油漆稀释剂、发动机和航油中的防爆剂少量使用。市售的二甲苯中含有最高达25％的乙苯，并在油漆、印染油墨、农药生产等过程中广泛使用。流行病学调查发现，乙苯的人群接触主要来自于石油化工行业的职业暴露，此外，汽车尾气和香烟烟雾也含有低水平乙苯，食品等其他消费品中也可见乙苯的残留。大量研究表明，大剂量乙苯接触可引起听力下降、肝。肾实质性损伤，严重者可诱发肿瘤。     

管道直饮水细胞遗传毒性研究

目的 探讨管道直饮水在小鼠骨髓细胞微核和体外成纤维细胞试验中是否具有细胞遗传毒性及细胞毒性作用.方法 ①细胞微核试验昆明小鼠60只,雌雄各半,随机分为6组.分别取2家管道直饮水和自来水作4个水样试验组,用环磷酰胺作阳性对照组,蒸馏水作阴性对照组,采用灌胃的途径对小鼠进行染毒,测定骨髓嗜多染红细胞微核率.②细胞毒性试验同样用上述4个水样作试验组,用新鲜的细胞培养液作阴性对照组,采用L-929细胞株置受试培养液培养,分别于更换受试培养液后第2、4和7天在倒置显微镜下进行细胞形态学观察、计数、分级,并与阴性对照组进行比较.结果 细胞微核试验中4个试验组细胞微核率(0.40±0.52、0.40±0.52、0.71±2.22、0.40±0.52)与阴性对照组(0.50±0.71)比较差异无统计学意义(P＞0.05),而与环磷酰胺阳性对照组(33.10±5.65)比较差异有统计学意义(P＜0.01).细胞毒性试验中4个试验组细胞形态正常,贴壁生长较好,呈棱形或不规则三角形,毒性级为0～1级,与阴性对照组比较无肉眼差异.结论 本次所检水样对小鼠骨髓嗜多染红细胞无致微核作用,无细胞毒性作用.     

浸提方法对药用卤化丁基橡胶塞体外细胞毒性评价的影响

目的:研究不同浸提方法对药用卤化丁基橡胶塞体外细胞毒性评价的影响。方法:采用不同的浸提方法制备了浸提液,以MTT法评价药用卤化丁基橡胶塞浸提液对小鼠成纤维细胞L929活性与增殖的影响。结果:通过不同的浸提方法制备的浸提液,11批中的9批样品体外细胞毒性实验出现了有统计学意义的差异。结论:破坏原有样品的正常形态即改变表面积与体积比对于评价卤化丁基橡胶塞的体外细胞毒性实验(MTT)是有影响的。     

In vitro genotoxicity assessment of commercial quartz flours in comparison to standard DQ12 quartz

Crystalline silica has been classified as a human carcinogen, but there is still considerable debate on its variable fibrogenic and carcinogenic potential. We investigated genotoxicity of a panel of four quartz flours in comparison to DQ12 standard quartz with similar size and surface area, using single cell gel electrophoresis (SCGE) or comet assay. A549 human lung epithelial cells were incubated for 4 hours with different concentrations of quartz ranging from 1.6 to 200 micrograms/cm2 and cytotoxicity was assessed using leakage of lactate dehydrogenase (LDH), trypan blue exclusion and conversion of a metabolic substrate (MTT). DNA strand breakages were seen with all quartzes at an in vitro concentration of 200 micrograms/cm2. At this concentration all tests and quartz samples showed significant cytotoxicity. The most toxic quartz flour (Qz 2/1-C) but not DQ12, showed an increase in strand breaks at 40 micrograms/cm2 in cell culture. At this concentration no cytotoxicity was seen with LDH and MTT, but a significant increase in cells with trypan blue uptake was noted. No differences in tail moment percentage were observed at equal concentrations of different quartz flours. Also no correlation between DNA damage and OH-radical generation or surface radicals as measured by electron spin resonance was observed. We conclude that quartzes do not cause strand breaks without concomitant cell toxicity and a sufficient in vitro concentration of > 40 micrograms/cm2 can only be reached in vivo with instillation of massive doses (> 100 mg). Therefore, in vitro genotoxicity found here is unlikely to explain the genotoxicity observed in in vivo studies with the same and other quartzes.     

Ecotoxicity and genotoxicity assessment of cytostatic pharmaceuticals

The fate and effects of cytostatic (anticancer or antineoplastic) pharmaceuticals in the environment are largely unknown, but they can contaminate wastewater treatment effluents and consequently aquatic ecosystems. In this paper, we have focused on five cytostatic compounds used in high amounts (cyclophosphamide, cisplatin, 5-fluorouracil, doxorubicin, and etoposide), and we have investigated their ecotoxicity in bacterial Pseudomonas putida growth-inhibition test, algal Pseudokirchneriella subcapitata growth-inhibition test, and Dapnia magna acute immobilization test. Genotoxicity also was assessed with Escherichia coli SOS-chromotest (with and without metabolic activation) and the GreenScreen Assay using yeast S. cerevisiae. All tested compounds showed significant effects in most of the assays with lowest-observed-effect concentrations and concentrations causing 50% effects (EC50s) values ranging within microg/L to mg/L. The most toxic compound was 5-fluorouracil in the assays with P. putida (EC50 = 0.027 mg/L) and P. subcapitata (EC50 = 0.11 mg/L), although cisplatin and doxorubicin were the most toxic to D. magna (EC50 = 0.64 and 2.0 mg/L, respectively). These two chemicals were also the most genotoxic in the SOS-chromotest (minimum genotoxic concentrations [MGC] = 0.07-0.2 mg/L), and 5-fluorouracil was the most genotoxic in the eukaryotic yeast assay (MGC = 0.02 mg/L). Our investigation seems to indicate generally lower risks of acute effects at concentrations expected in the environment. However, some effective concentrations were relatively low and chronic toxicity of cytostatics (and/or their transformation products), as well as specific sources of human pharmaceuticals such as hospital effluents, require research attention.     

使用体内遗传毒性综合测试体系评价顺铂的遗传毒性

目的使用大鼠体内遗传毒性综合测试体系全面评价顺铂的遗传毒性,为顺铂临床应用提供重要依据。方法雄性SD大鼠(150～160 g)25只,每组5只。溶剂对照组为0.9%生理盐水,顺铂剂量组分别为0.125、0.25、0.5、1 mg/kg.bw,均按5 ml/kg.bw腹腔注射连续28 d染毒。于试验第0、14、28、42、56、84、112 d进行外周血Pig-a基因突变试验;于试验第0、4、28 d进行外周血微核试验;于试验第4、28 d给药后4 h进行外周血彗星试验。主要遗传毒性指标使用ANOVA进行假设检验,使用Dunnett-t进行剂量组和对照组之间的比较(检验水准α=0.05,双侧)。结果 Pig-a基因突变试验,0.250～1.000 mg/kg.bw组RBCs突变率和RETs突变率均有升高,与对照组比较差异有统计学意义。外周血微核试验,0.500～1.000 mg/kg.bw组RET微核率均有显著升高,与对照组比较差异有统计学意义;彗星试验,0.500～1.000mg/kg.bw组尾部DNA含量均有显著增加,与对照组比较差异有统计学意义。结论顺铂体内重复染毒具有引起DNA损...     

In vitro and in vivo micronucleus tests in genotoxicity research

Working and living environment today is an unpredictable mixture of different chemical substances. Some of these chemicals are mutagenic carcinogens and others are aneugenic carcinogens. An additional burden to the human genome is the exposure to several kinds of radiations. Among a dozen genotoxicological methods in use in vitro and in vivo, the micronucleus assay has found application in the basic research, clinical research, and pharmacological studies. The advantage of in vivo and in vitro micronuclues assays is in the fact that they provide data on both clastogenic and aneugenic action of agents. Although several years behind the in vitro technique, the in vivo micronucleus assay has swiftly developed into a significant source of data in acute and chronic genotoxic investigations, as it does not require cell culture.     

低强度2 450 MHz微波对丝裂霉素C遗传毒性作用影响的体外实验

目的研究低强度2 450 MHz微波是否增强丝裂霉素C(MMC)对人外周血淋巴细胞的遗传毒性.方法采用彗星试验和胞质分裂阻断微核试验(CBMN),在体外检测2 450 MHz微波(5.0mW/cm2)与MMC诱发的DNA单链断裂及染色体损伤的情况.结果微波辐射组外周血淋巴细胞的彗星长度[男、女分别为(29.1±8.1)、(25.9±7.5)μm]与对照组[男、女分别为(26.3±6.6)、(24.1±4.3)μm]比较,差异无显著性(P＞0.05);MMC各剂量组(0.012 5、0.025 0、0.050 0、0.100 0μg/ml)的彗星长度均长于对照组,差异有显著性(P＜0.01),而且随着MMC剂量的增加,彗星长度增长;微波联合MMC(MW+MMC)各剂量组的彗星长度也随着MMC剂量增加而增长,且明显长于对照组,差异亦有显著性(P＜0.01),当MMC≥0.025 0μg/ml时,微波与MMC可协同增加DNA单链断裂.微核试验结果表明,微波组的微核率与对照组的差异无显著性(P＞0.05).MMC组和MW+MMC组在MMC≥0.050 0μg/ml时,其微核率与对照组比较,差异有显著性(P＜0.05或P＜0.01).MW+MMC组的微核率高于相应的MMC组,但差异无显著性(P＞0.05).结论低强度2450 MHz微波辐射未能诱发人外周血淋巴细胞DNA和染色体损伤,但彗星试验显示,其可增强MMC诱发的DNA单链断裂效应.     

抗菌脂肽对体外哺乳动物细胞遗传毒性的研究

目的研究抗菌脂肽对体外哺乳动物细胞的遗传毒性。方法根据细胞毒性试验结果,在存在/不存在代谢活化系统条件下:分别设86、43、22mg/L和36、18、9mg/L 3个剂量组,以抗菌脂肽作用中国地鼠肺成纤维细胞(CHL),分析CHL染色体致畸变率;分别设7.5、15、30、60、120mg/L和2.5、5、10、20、40mg/L 5个剂量组,以抗菌脂肽作用中国仓鼠肺成纤维细胞(V79),通过HGPRT基因突变试验,计算相对集落形成率,评估抗菌脂肽对体外哺乳动物细胞的致突变性。结果在存在/不存在代谢活化系统条件下,抗菌脂肽对CHL细胞染色体畸变率为2.0%~4.0%;作用V79细胞后,MF均11.0×10-6;均低于阳性对照,差异均有统计学意义(P值均0.05)。以上指标与阴性对照组差异均无统计学意义(P值均0.05)。结论在体外试验条件下,抗菌脂肽对哺乳动物细胞无致突变性或潜在的遗传毒性。     

Health impact assessment of housing improvements: incorporating research evidence

BACKGROUND: Health impact assessment (HIA) has been widely recommended for future social policies and investment, such as housing improvement. However, concerns have been raised about the utility and predictive value of an HIA. Use of existing research data would add more weight to forecasts by an HIA. METHODS, RESULTS, and CONCLUSIONS: A recent systematic review of housing intervention studies found a lack of research. The authors recommended that a broader evidence base would be needed to support HIA. In response to consultation with policymakers and HIA practitioners this paper presents a way in which research can be used to inform HIA. Based on the systematic review, the authors have developed a table of synthesised findings indicating the expected health effects of specific housing improvements. The authors also reviewed observational data of housing associated health risks to highlight the key impacts to consider when doing a housing HIA. The findings are presented and the authors discuss how they should be used to inform evidence based housing HIA. In addition to considering the existing research, HIA must consider the local relevance of research. Consultation with local stakeholders also needs to be incorporated to the final assessment. The lack of data and the difficulties in gathering and reviewing data mean that not all HIAs will be able to be informed by research evidence. Well conducted prospective validation of HIAs would contribute to the development of healthy housing investment by informing future housing HIA.     

A critical assessment of mortality statistics in Thailand: potential for improvements

This study evaluates the collection and flow of mortality and cause-of-death (COD) data in Thailand, identifying areas of weakness and presenting potential approaches to improve these statistics. Methods include systems analysis, literature review, and the application of the Health Metrics Network (HMN) self-assessment tool by key stakeholders. We identified two weaknesses underlying incompleteness of death registration and inaccuracy of COD attribution: problems in recording events or certifying deaths, and problems in transferring information from death certificates to death registers. Deaths occurring outside health facilities, representing 65% of all deaths in Thailand, contribute to the inaccuracy of cause-of-death data because they must be certified by village heads with limited knowledge and expertise in cause-of-death attribution. However, problems also exist with in-hospital cause-of-death certification by physicians. Priority should be given to training medical personnel in death certification, review of medical records by health personnel in district hospitals, and use of verbal autopsy techniques for assessing internal consistency. This should be coupled with stronger collaboration with district registrars for the 65% of deaths that occur outside hospitals. Training of physicians and data coders and harmonization of death certificates and registries would improve COD data for the 35% of deaths that take place in hospital. Public awareness of the importance of registering all deaths and the application of registration requirements prior to funerals would also improve coverage, though enforcement would be difficult.