大同盆地砷、氟中毒地方病生态地球化学研究

山西大同盆地属干冷荒漠景观条件的半封闭型断陷盆地。区内有害元素的聚集导致氟中毒等多种地方病肆虐,20世纪90年代因开发和饮用深层地下水爆发了水砷中毒病。经地球化学调查发现:地下潜水高含F,超标1.3～12倍;深层承压地下水富As,砷含量超标2～20倍。砷中毒发病率与饮水中As3+/∑As比值呈正相关关系。盆地周边分布多层富含As和F的地层和火成岩体,处于富As、F的区域地球化学省内。由于大同盆地的不均匀沉降,在其边缘部分形成深凹陷带,含砷下渗地下水经有机碳质层的还原作用,使砷还原为三价,提高了地下水的毒性并滞留聚集。探讨了F、As富集和中毒的机理和生态地球化学危害评价,提出了治理和外围调查预测建议。     

尼罗罗非鱼淋巴毒素α基因克隆与表达分析

【目的】克隆尼罗罗非鱼(Oreochromis niloticus)淋巴毒素α基因(lymphotoxin alpha, LTα),分析该基因的组织分布,探讨该基因在抗菌抗病毒免疫过程中的重要作用。【方法】通过RACE技术获得尼罗罗非鱼淋巴毒素α基因(On-LTα)的cDNA全长,通过生物信息学分析其序列结构特征;利用实时荧光定量PCR检测基因的组织分布特征,以及健康尼罗罗非鱼感染无乳链球菌后该基因的表达变化,并进一步分离出尼罗罗非鱼非特异性毒性细胞(NCC),检测脂多糖(LPS)和聚肌胞苷酸(Poly I:C)刺激后,On-LTα在NCC中的表达变化。【结果】On-LTα基因序列全长为2699 bp,包含705 bp开放阅读框(ORF),编码234个氨基酸(GenBank登录号:MK770358)。该蛋白属于跨膜蛋白,具有肿瘤坏死因子(TNF)家族保守结构域。实时荧光定量结果表明,On-LTα在健康尼罗罗非鱼11种组织中均有表达,在脾脏中的表达量最高;无乳链球菌刺激后,该基因在脾脏中的表达量显著升高;LPS与PolyI:C刺激后,On-LTα在NCC中表达量也显著上调。【结论】On-LTα参与了尼罗罗非鱼抗菌抗病毒的免疫应答过程。     

尼罗罗非鱼非特异性细胞毒性细胞(NCC)分离条件的优化

破碎尼罗罗非鱼(Oreochromis niloticus)头肾组织,用RPMI-1640培养基制成细胞悬液,添加至两层不同浓度的Percoll分离液液面,离心,得非特异性细胞毒性细胞(Non-specific cytotoxic cell,NCC),优化下层Percoll浓度、离心力、离心时间。结果表明,当下层Percoll体积分数为43%,上层Percoll体积分数为34%,离心力为500 g,离心时间为30 min时,尼罗罗非鱼NCC得率最高,为71.28%。     

The toxic mechanism of high lethality of herbicide butachlor in marine flatfish flounder, <Emphasis Type="Italic">Paralichthys olivaceus</Emphasis>

The toxic mechanism of herbicide butachlor to induce extremely high lethality in marine flatfish flounder, Paralichthys Olivaceus, was analyzed by histopathological examination, antioxidant enzymes activities and ATP content assay. Histopathological examination of gill, liver and kidney of exposed fishes showed that gill was a target organ of butachlor. The butachlor seriously impaired the respiration of gills by a series of lesions such as edema, lifting and detachment of lamellar epithelium, breakdown of pillar cells, and blood congestion. The dysfunction of gill respiration caused suffocation to the exposed flounder with extremely high acute lethality. Antioxidant enzyme activity assay of the in vitro cultured flounder gill(FG)cells exposed to butachlor indicated that butachlor markedly inhibited the antioxidant enzyme activities of Superoxide dismutase(SOD), catalase(CAT)and glutathione peroxidase(GPX). Furthermore, along with the decline of antioxidant enzyme activities, ATP content in the exposed FG cells decreased, too. This infers that the oxidative stress induced by butachlor can inhibit the production of cellular ATP. Similar decrease of ATP content was also observed in the exposed flounder gill tissues. Taken together, as in FG cells, butachlor possibly induced a short supply of ATP in pillar cells by inhibiting the antioxidant enzyme activities and then affecting the contractibility of the pillar cells, which in turn resulted in the blood congestion and suffocation of exposed flounder.     

土壤中铬的毒性阈值(ECx)及其预测模型

毒物学资料的缺乏成为制约我国污染土壤中Cr生态风险评价及土壤环境质量标准修订的主要瓶颈。本研究选取了我国7种不同性质土壤,分别以蚯蚓生物量、小白菜生物量和微生物基质诱导呼吸(SIR)为毒性测试终点,基于Log-logistic剂量-效应关系及低剂量刺激效应函数模型对不同土壤中铬的毒性阈值(EC_x)进行了测定,在此基础上,对不同性质土壤中Cr的毒性阈值进行了预测。研究结果表明：不同性质土壤中Cr对蚯蚓、小白菜、土壤微生物毒性均随着土壤Cr含量的增加而表现出明显抑制效应,剂量-效应关系呈现明显的S型曲线;不同性质土壤中,基于微生物(SIR)、蚯蚓、小白菜毒性测试的EC₁₀分别为22.1～53.7、65.0～137.2和82.1～220.2 mg/kg, EC₅₀分别为50.3～103.7、103.9～369.0和159.9～441.9 mg/kg;不同物种Cr毒性阈值由大到小顺序为小白菜>蚯蚓>土壤微生物,土壤微生物对Cr毒性最为敏感;在土壤Cr低含量(<112 mg/kg)条件下,3种测试物种对Cr毒性表...     

Toxic Effects of Phthalates on Ocean Algae

This article discusses the interaction of phthalates and ocean algae based on the standard appraisal method of chemical medicine for algae toxicity. Through the experiments on the toxic effects of dimethyl （o-） phthalate （DMP）, diethyl （o-） phthalate （DEP）, dibutyl （o-） phthalate （DBP） on ocean algae, the 50 % lethal concentration of the three substances in 48 h and 96 h for plaeodectylum tricornutum, platymonas sp, isochrysis galbana, and skeletonema costatum is obtained. Tolerance limits of the above ocean algae of DMP, DEP, and DBP are discussed.     

海洋微生物对甲胺磷农药的降解作用

作者从沿岸海域分离了38株有机磷农药的耐药菌,用分批培养法进行富集培养,得到有机磷农药的降解菌,并着重研究了其中两株菌对甲胺磷农药的降解情况,其结果表明,在10d内,降解菌株1对甲胺磷的降解率为59．1％,降解菌株2的降解率为53．3％,在各自的安磷培养液中,降解菌株1的数量大于降解菌株2;在甲胺降解过程中,其毒性逐渐减弱,降解菌株1所引起的毒性下降幅度大于降解菌株2。     

鄱阳湖水体沉积物中Zn、Cd对底栖生物的毒性效应及基准验证

以泥鳅（Misgurnus anguillicaudatus）、铜锈环棱螺（Bellamya aeruginosa）、河蚬（Corbicula fluminea）为受试生物,以死亡率、渗血率、体质量变化、行动迟钝率、挖洞率为测试指标,探究沉积物中Zn和Cd对底栖生物的21 d慢性毒性效应,并对鄱阳湖Zn和Cd的沉积物基准值进行了验证.结果表明,沉积物中Cd对底栖生物的毒性效应强于Zn,沉积物中Zn、Cd对泥鳅、铜锈环棱螺、河蚬的LC₅₀（半数致死浓度）分别为644和61 mg/kg、751和54 mg/kg、652和81 mg/kg,EC₅₀（半数效应浓度）值分别为526和49 mg/kg、589和35 mg/kg、474和45 mg/kg.经验证,沉积物Zn和Cd的TEL（临界效应浓度）、PEL（必然效应浓度）值比较合理,具有一定适用性,即当Zn、Cd的加标含量低于TEL值时,Q_TEL<1,不具有毒性;当加标含量高于PEL值时,Q_PEL>1,毒性明显.     

An In Vitro Investigation of Pulmonary Alveolar Macrophage Cytotoxicity Introduced by Fibrous and Grainy Mineral Dusts

In order to study the damage mechanism of mineral dusts on the pulmonary alveolar macrophage （AM）, the changes in their death ratio, malandialdthyde （MDA） content and activities of lactate dehydrogenase （LDH） and superoxide dismutase （SOD） were measured, and the technique of cell culture in vitro was used to investigate the cytotoxicity of six mineral dusts （twelve crystal habits） from twelve mineral deposits. The results show that woUastonite and clinoptilolite have no AM cytotoxicity, while other fibrous and grainy mineral dusts damage pulmonary AM in various degrees. The cytotoxicity of fibrous mineral dusts was greater than that of the grainy ones, and the cytotoxicity of dusts was positively correlated with the active OH- content in dusts, but not necessarily so with its SiO2 content. The high pH values produced by dust was unfavorable for the survival of cells and the dusts with low bio-resistance were safe for cells. The content of variable valence elements in dusts might influence their cytotoxicity and the surface charge of dusts was not a stable factor for their toxicity. It is demonstrated that the shape of mineral dusts was one of the factors affecting cytotoxicity, and that the cytotoxicity of mineral dusts depends mainly on their properties.