Induction of micronuclei in human lymphocytes after occupational exposure to ultrasound

Micronucleus assay combined with Giemsa and DAPI staining was performed on blood samples of subjects occupationally exposed to ultrasound. Lymphocytes were cultivated in vitro for 72 h. At 44h cytochalasin-B was added in cultures. Frequencies of micronuclei in exposed subjects statistically significant increased compared to control. The frequency of micronucleated cells and micronuclei in exposed subjects shows interindividual variability. Using DAPI staining we observed signal-positive and signal-negative micronuclei. Percentage of signal-positive micronuclei varies between 0 and 66.7% and signal-negative micronuclei between 33.3% and 100%. This study indicate harmful effects of ultrasound on human genome, but further investigations are necessary.     

亚硒酸盐对蚕豆根尖细胞的遗传损伤效应

采用蚕豆根尖微核实验和姊妹染色单体交换实验，研究亚硒酸盐的遗传损伤效应．结果表明：0．1～50．0μg／g的亚硒酸氢钠(NaHSeO3)处理12h可诱发蚕豆根尖细胞遗传损伤，导致根尖细胞有丝分裂指数下降，间期具有微核的细胞数显著增多，姐妹染色单体交换(SCE)频率明显增高；且根尖微核细胞率与处理浓度间具有正相关，分裂指数与处理浓度间呈负线性相关，分裂指数与微核率之间表现负相关．研究结果提示：硒能破坏生物的遗传稳定性，职业接触或饮食补硒时应避免其毒害作用．图1表4参17     

Evaluation of the clastogenicity of isoprothiolane and pyroquilon using the mouse micronuclei test

We estimated the clastogenicity of isoprothiolan (diisopropyl 1,3-dithiolan-2-ylidenemalonate) and pyroquilon (1,2,5,6-tetrahydropyrrolo [3.2.1-ij] quinolin-4-one), using an in vivo mouse peripheral blood micronuclei assay to measure their effects on gene toxicities. The present data showed that purified samples of isoprothiolane and pyroquilon were not clastogenic data in this assay, whereas the commercial compounds we purchased had demonstrated clastogenic reactions. Our study showed that we must evaluate the pesticides that have been purified in parallel with that of commercial products containing impurities that are used in the field.     

Bioconcentration and Phytotoxicity of Cd in Eichhornia crassipes

Plants of Eichhornia crassipes grown at various levels of cadmium ranging from 0.1 to 100 μg ml⁻¹ accumulated Cd in a concentration and duration dependent manner. At all levels, Cd accumulation by various plant tissues followed the order roots shoot leaves. Approximately 80% of total Cd was accumulated by plant at highest concentration (100 μg ml⁻¹) used in the experiment. Cadmium induced phytotoxicity appears at 25.0 μg ml⁻¹ resulting into reduced levels of chlorophyll, protein and in vivo nitrate reductase activity of the plant. However, a slight induction of these physiological variables was obtained at lowest Cd (0.1 μg ml⁻¹) concentration. In contrast, carotenoid content increased at highest Cd concentration i.e., 100 μg ml⁻¹. Similar effects at low and high levels of Cd was obtained with respect to mitotic index and micronuclei in root meristem of the plant. It could be inferred that Cd toxicity in plant is differential depending upon the low and high concentration of Cd in the medium.     

低浓度溴氰菊酯连续暴露对罗非鱼DNA的影响

运用RAPD技术和外周血嗜多染红细胞微核试验来分析和评价低浓度溴氰菊酯连续暴露对罗非鱼DNA的影响.RAPD试验结果表明,在12个能扩增出罗非鱼基因组DNA的引物中,引物S326能检测出3 μg/L以上浓度溴氰菊酯暴露前后罗非鱼基因组DNA的差异,而小于2.0 μg/L的低浓度溴氰菊酯对罗非鱼基因组DNA没有影响.外周血嗜多染红细胞微核试验结果表明,在一定浓度的溴氰菊酯连续暴露后,2.0 μg/L以下浓度组罗非鱼外周血红细胞微核率与对照组相比没有显著差异(P＞0.05),而3 μg/L以上浓度组可诱导罗非鱼外周血红细胞产生微核.微核率与对照组相比差异显著(P＜0.05),且表现出明显的剂量-效应和时间-效应关系.研究表明,溴氰菊酯在一定条件下可对鱼类DNA产生影响.     

硫酸厂工人外周血淋巴细胞微核率的研究

SO₂是硫酸厂、冶炼厂和火力发电厂等厂矿及其周围环境最常见的大气污染物之一。虽然有的研究者曾设想SO₂可能引起细胞染色体改变甚至诱发癌症,但有关SO₂引起细胞染色体损伤效应的研究甚少。近年来,Nordenson等曾报道,接触SO₂的工人其外周血淋巴细胞染色体畸变率增高。目前多数学者认为染色体断裂后遗留下来的无着丝粒断片可在细胞分裂后期仍留在细胞质中而形成微核,加之微核测定又是比染色体畸变分析较为简单、快速的细胞遗传学方法,故国际致突物和致癌物防护委员会(ICPEMC)将此项技术列为致突致癌研究的必测项目之一。     

硫酸厂工人外周血淋巴细胞微核率的研究

SO_2是硫酸厂、冶炼厂和火力发电厂等厂矿及其周围环境最常见的大气污染物之一。虽然有的研究者曾设想SO_2可能引起细胞染色体改变甚至诱发癌症,但有关SO_2引起细胞染色体损伤效应的研究甚少。近年来,Nordenson等曾报道,接触SO_2的工人其外周血淋巴细胞染色体畸变率增高。目前多数学者认为染色体断裂后遗留下来的无着丝粒断片可在细胞分裂后期仍留在细胞质中而形成微核,加之微核测定又是比染色体畸变分析较为简单、快速的细胞遗传学方法,故国际致突物和致癌物防护委员会(ICPEMC)将此项技术列为致突致癌研究的必测项目之一。     

SO2衍生物对大蒜根尖细胞遗传损伤作用的研究

研究SO2体内衍生物--亚硫酸钠和亚硫酸氢钠混合液(31,mol.L-1/mol.L-1)对大蒜幼根细胞的遗传损伤效应.结果表明SO2衍生物处理可导致根尖细胞分裂异常,中期染色体粘连、间期细胞微核和双核频率明显增高;此外还可引起根尖部分细胞核碎解及核固缩.SO2体内衍生物的上述效应具有明显的时间-效应和剂量-效应关系.     

垃圾填埋场渗滤液诱发小鼠骨髓细胞微核效应

研究了垃圾填埋场渗滤液诱发小鼠骨髓嗜多染红细胞(PCE)微核(MN)效应.结果表明,渗滤液可诱发微核的形成,且呈明确的浓度(渗滤液COD_Cr)-效应关系.在亚急性染毒条件下,渗滤液COD_Cr为10mg/L时,可诱发微核率和微核细胞率显著高于阴性对照(n=16,P<0.001);在亚慢性染毒条件下,渗滤液COD_Cr为5mg/L时,即可诱发微核率和微核细胞率显著高于阴性对照(n=16,P<0.001).这一结果从整体水平上证明了垃圾填埋场渗滤液对哺乳动物具有遗传损伤效应,同时提示可以以小鼠骨髓嗜多染红细胞微核试验结果作为渗滤液生物监测指标.渗滤液处理时间越长,引起细胞遗传损伤所需的最低浓度越低,意味着长期接触环境低浓度渗滤液污染有引起体内细胞遗传物质损伤的潜在危险.     

铝对蚕豆根尖细胞的遗传损伤

铝作为土壤主要元素之一,是酸性条件下影响植物生长发育的一个主要原因。为进一步探讨酸性条件下铝对植物细胞的毒性作用机理,文章以蚕豆(ViciafabaL.)为材料,研究了不同酸度(pH4.5和pH5.8)的三氯化铝对根尖细胞的遗传损伤作用。结果表明,pH5.8和pH4.5的铝处理(0.03~50mmol·L-1)组中根尖细胞分裂指数呈浓度依赖性降低,微核细胞数显著增加。相同铝浓度时,pH4.5组的分裂指数低于pH5.8组,微核率高于后者。此外,铝处理能诱发根尖细胞核固缩,固缩率随酸度增强和铝浓度增大而增高。研究结果表明,三氯化铝对蚕豆根尖细胞具有遗传损伤作用,酸性增强时铝的毒性作用增强。