Endosulfan acute toxicity and histomorphological alterations in Jenynsia multidentata (Anablepidae,Cyprinodontiformes)

Toxicity tests using adult specimens of Jenynsia multidentata were carried out during 96 hours in order to determine the lethal concentration (LC50) of endosulfan. Histological alterations were determined in gills and liver. Gill damage was quantified as secondary lamellae thickness. The 96 hr LC50 values were significantly different between males (0.719 μ g.L^{? 1}) and females (1.317 μg.L^{? 1}). The sex difference was attributed to the dimorphism in the lipid content in females (2.16%) and males (1.79%). Histological alterations in gills included hypertrophy and lifting of the epithelium of the secondary lamellae and aneurisms. These alterations caused a significant increase of the secondary lamellae thickness in treatment versus control fish. Finally, reversible histological alterations (such as hydropic degeneration and dilation of sinusoids) were observed in the liver of exposed fish as well as an irreversible change such as necrosis at the highest concentrations.     

Effect and mechanism of action of methomyl and cypermethrin insecticides on kynurenine metabolizing enzymes of mouse liver

Abstract

The effect of methomyl and cypermethrin insecticides on the B₆‐dependent kynurenine hydrolase(KH) and kynurenine aminotransferase (KATE) was studied. These insecticides induced pronounced inhibition on the (KH) and (KATE) enzymes after single dose treatment. Repeated doses of methomyl induced inhibition on the (KH) and (KATE) activities, whereas repeated treatment with cypermethrin had no effect on the activities of these enzymes. In vitro methomyl inhibited (KH) and (KATE) enzymes at 10 M up to 10^‐3 M, through a competitive mechanism. Methomyl and cypermethrin are capable of causing alterations in the kynurenine metabolizing enzymes of mouse liver.     

烧烤场景中基于PBPK模型的人群PAHs暴露评估

为探究烧烤场景中人群多环芳烃(PAHs)的暴露特征与健康风险,使用美国环保署推荐的计算模型和基于生理的药代动力学模型(PBPK)模拟了我国人群的PAHs外暴露剂量和健康风险以及内暴露剂量变化情况。结果表明:1)普通居民和职业人群的日均苯并[a]芘等效摄入剂量为(50±3)ng·d~(-1)和(179±98)ng·d~(-1),其终生致癌风险为7.57×10~(-7)~1.28×10~(-5),均在可接受范围内;2)普通居民暴露后体内组织中PAHs内暴露标志物芘的最大浓度范围依次为肝(6.52~8.67 ng·L~(-1))肾(0.97~1.12 ng·L~(-1))静脉血(0.71~0.94 ng·L~(-1))皮肤(0.64~0.75 ng·L~(-1))脂肪(0.36~0.56 ng·L~(-1)),职业人群暴露后体内组织芘最大浓度为脂肪(2.97ng·L~(-1))皮肤(1.14 ng·L~(-1))≥肾(1.14 ng·L~(-1))肝(0.57 ng·L~(-1))静脉血(0.17 ng·L~(-1));3)膳食是普通人群的主导暴露途经,会导致肝组织浓度最大;呼吸和皮肤接触是职业人群的主导暴露途经,会导致脂肪组织浓度最大;4)暴露标志物芘的组织总富集量关系为职业人群(48 ng·d~(-1))大于普通人群(6~11 ng·d~(-1))。     

三(1,3-二氯-2-丙基)磷酸酯诱发肝脏损害及病理改变研究

本研究观测有机磷酯阻燃剂(OPFRs)污染是否可以诱发肝脏损害,考察其发生及发展程度,并探讨其发生机理,为有机磷阻燃剂污染的防治和相关疾病的有效治疗提供基础数据和科学依据。实验以大鼠为动物模型,将60只SPF级SD雄性大鼠分为5组,每组12只,选取典型的氯代有机磷阻燃剂三(1,3-二氯-2-丙基)磷酸酯(TDCPP)对大鼠进行染毒,空白对照组不做任何处理,溶剂对照组以相同体积的橄榄油灌胃,染毒组以不同剂量的TDCPP进行灌胃(125 mg·kg~(-1)·d~(-1)、250 mg·kg~(-1)·d~(-1)和500 mg·kg~(-1)·d~(-1)),每周测量体重,于第4周和第8周取血检测肝功及其他生化指标,在第8周每组抽取3只大鼠取肝脏组织做HE染色,并用透射电镜观察分析肝组织病理学改变。TDCPP对大鼠染毒8周后,结果表明:(1)体重指标在灌胃1周后开始发生差异,TDCPP处理组大鼠的体重有下降的趋势,染毒组与空白对照组和溶剂对照组相比较,差异显著(*P0.05,**P0.01),其中高剂量灌胃组的体重下降最为明显(**P0.01);(2)血清肝功指标表现出显著变化,血清谷丙转氨酶、谷草转氨酶、胆固醇和甘油三脂水平在第8周呈现明显下降趋势,染毒组与空白对照组和溶剂对照组比较,差异明显(*P0.05,**P0.01);(3) TDCPP暴露组生理生化指标变化明显,血清乙酰胆碱酯酶活性显著降低,MDA含量显著升高,SOD活力显著性降低,造成氧化损伤,与空白对照组和溶剂对照组比较,差异显著(*P0.05,**P0.01);(4)病理切片结果显示染毒组与对照组比较,细胞坏死现象明显,且高剂量组坏死更为严重。研究结果显示:TDCPP可引起大鼠体重明显下降,大鼠肝脏细胞损伤、合成功能下降,造成肝脏代谢功能紊乱,造成较为严重的肝损伤。     

羟基多溴联苯醚(OH-PBDEs)小鼠肝脏微粒体体外代谢及对雌激素代谢的影响研究

羟基化多溴联苯醚(OH-PBDEs)是一类具有内分泌干扰效应的酚类化合物,以小鼠肝脏微粒体作为研究对象,考察了OH-PBDEs的体外代谢行为及对雌激素代谢的影响。研究结果发现,4种OH-PBDE均能够代谢,其代谢率大小为6-OH-BDE-996’-OH-BDE-996-OH-BDE-1375’-OH-BDE-99,表明羟基官能团(-OH)与醚键及溴原子处于邻位时,表现出较高的代谢率; 4种OH-PBDE对3种天然雌激素包括雌酮(E1)、17β-雌二醇(E2)、雌三醇(E3)的代谢表现出不同作用,整体来说,对E1和E2代谢随着OH-PBDE浓度的增加抑制作用逐渐增强,对E3代谢则表现出促进作用,但是对人工合成的雌激素17α-炔雌醇(EE2)无明显影响;对E2代谢产物2-羟基雌二醇(2-OH-E2)的生成量定量表征表明,除6-OH-BDE-99促进了2-OH-E2的生成量,其余3种OH-PBDE随实验添加浓度的增加,抑制了2-OH-E2的生成量,这可能与酶介导的不同代谢机制有关。     

孕期低剂量镉暴露对不同性别胎鼠肝脏发育的影响及其分子调控机制的研究

为探究镉对胎儿肝脏发育的毒性作用.拟选用15只性成熟的8周龄的雌性C57BL/6小鼠,与雄鼠交配见栓后,于妊娠第7.5 d(Embryonic 7.5,E7.5)时,随机分为3组(每组5只),分别通过饮用水暴露法饲喂0、20和40 mg·L^-1的氯化镉溶液,并于E14.5 d时收集各组小鼠的胎儿肝脏等组织.通过Ki67和TUNEL染色方法探究镉对不同性别胎鼠肝脏的增殖功能和凋亡功能的影响,并通过PCR芯片筛查和实时定量PCR方法检测镉处理组的雌性和雄性胎鼠肝脏中与细胞增殖和凋亡功能相关基因的表达变化.此外,我们还将通过石墨炉火焰原子吸收技术对镉处理组的雌性和雄性胎鼠的镉含量进行检测.结果显示:孕期低剂量镉暴露对胎儿体重、胎肝重量和肝脏指数均无显著性影响.在本实验条件下,镉对胎鼠肝脏的凋亡功能无显著性影响,但对增殖功能具有抑制作用,且该抑制作用具有雌性依赖性的特征.镉特异性诱导雌性胎鼠肝脏中NF1等多个细胞增殖功能相关基因以及TGF-β1信号通路分子的表达失衡;但对雄性胎鼠肝脏中相关基因的表达水平无显著性影响.镉在雌性胎儿组织中的积累量显著高于雄性胎儿组织.综上所述,孕期低剂量镉暴露特异性抑制雌性胎儿肝脏的细胞增殖功能,并诱导雌性胎儿肝脏中NF1等多个增殖功能相关基因以及TGF-β1信号通路分子的表达失衡,该性别依赖性的抑制作用可能与镉在雌性胎儿中相对较高的积累量相关.     

BIOLOGICAL INDICATORS AND BIOLOGICAL EFFECTS OF ESTUARINE/COASTAL POLLUTION1

ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.     

江西省肝癌与岩石类型

利用岩石类型资料１０９２个数据，肝癌死亡调查资料１５４４例，研究了肝癌死亡率与人群生存区的岩石类型（岩浆岩、变质岩、碳酸盐岩、碎屑岩、红色碎屑岩、第四系松散岩）的相关性。在此基础上，综合评价了与肝癌有相关性的岩石类型对肝癌的产生和发展的影响。     

Determination of cytotoxic,genotoxic, and oxidative damage from deltamethrin on primary hepatocyte culture of Lake Van fish,Alburnus tarichi

ABSTRACT

Deltamethrin is a widely used pyrethroits worldwide. Although the chemical is used to combat insects, it has effects on other non-target organisms. Deltamethrin is extensively used in agriculture, animal husbandry, and domestic areas in the Lake Van basin. The aim of this study was to determine the cytotoxic, genotoxic, and oxidative damage from deltamethrin on the primary hepatocyte culture of Lake Van fish (Alburnus tarichi). In this study, the toxic effects of different concentrations (0.01, 0.1, 1, and 10?µM) of deltamethrin in the primary hepatocyte culture of Lake Van fish were investigated via liver enzymes aspartase aminotransferase (AST) and alanine aminotransferase (ALT), and the total antioxidant status (TAS), total oxidant status (TOS), lipid peroxidation (MDA), and DNA damage (8-OHdG).

Deltamethrin caused an increase in the AST and ALT levels dependent on the dosage and time. The TAS and TOS levels increased at the end of 24?h and there was no difference at the end of 48?h. Deltamethrin did not affect the MDA level, but increased the 8-OHdG (P?<?0.05). In conclusion, it can be said that high doses of deltamethrin (1 and 10?µM) have a toxic effect on the primary hepatocyte culture of Lake Van fish.