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1.
采用腹腔注射方式(每周1次,共5次)将生活于淡水或海水中的日本鳗鲡(Anguilla japonica)暴露于三丁基锡氯化物(TBTCl)和菲(Phe),以研究这两种污染物对鳗鲡的毒性效应以及该效应与鱼体所处环境盐度的关系.鳗鲡暴露于TBTCl或Phe1w后,其肝脏和脾脏的组织结构就已发生明显病变,且病变程度随着暴露时间的延长而加剧,其中海水鳗鲡比淡水鳗鲡表现更为严重;但肝体指数(HSI)和性腺组织结构均无明显变化.暴露于TBTCl4~5w后,海水鳗鲡肝脏的谷胱甘肽-S-转移酶(GST)活性比对照组显著升高,而淡水鳗鲡组无明显变化;暴露于TBTCl或Phe3w后,淡水鳗鲡的血浆皮质醇水平显著升高,但海水鳗鲡组无明显变化.TBTCl和Phe对淡水或海水鳗鲡的血浆雌二醇(E2)水平均无明显影响.以上结果表明:有机锡和菲对鳗鲡的肝脏、脾脏有毒性作用,对皮质醇分泌具有内分泌干扰作用,且该效应与暴露时间和鱼体所处环境盐度有关.  相似文献   

2.
林丹短期暴露下的斑马鱼(Brachydanio rerio)组织学变化   总被引:2,自引:0,他引:2  
以斑马鱼(Brachydaniorerio)为受试生物,初步探讨了林丹对斑马鱼的急性毒性以及不同浓度(0.01μg·L-1、1.0μg·L-1、100.0μg·L-1)的林丹暴露36d后对斑马鱼鳃和肝组织结构变化的影响.结果表明,林丹对斑马鱼96h-LC50为97.98μg·L-1,95%可信限为94.38 ̄101.72μg·L-1.当林丹浓度为0.01μg·L-1时,斑马鱼的鳃和肝组织结构未发生明显变化,而暴露在1.0μg·L-1和100.0μg·L-1林丹溶液中的斑马鱼的鳃和肝组织结构变化显著.斑马鱼鳃组织变化为:上皮细胞残损、脱落,鳃小片上皮细胞水肿,柱细胞变形.斑马鱼肝组织变化为:部分肝细胞肿大,细胞核萎缩变形或偏离细胞中心,胞质疏松,空泡明显增加,细胞质中可见脂沉积.与1.0μg·L-1林丹暴露相比,暴露在100μg·L-1林丹溶液中的斑马鱼鳃和肝组织结构受到的损害更为严重.  相似文献   

3.
This review will focus primarily on ohe effects of the inorganic arsenicals (arsenate and arsenite forms) that are present in drinking water. They are acutely toxic to both humans and animals, an effect that may be related to their bioavailibility. In humans, arsenicals have been reported to cause dermatitis and mucous membrane irritation upon exposure. They have also been reported to cause skin lesions and peripheral neurotoxicity in smelter workers and in patients treated with Fowler's Solution. When humans are exposed to arsenic in drinking water, effects such as hyperkeratosis, electromyographic abnormalities and vascular effects have been reported. In experimental animals, arsenic has been demonstrated to affect the liver and kidneys. In mice, arsenic has also been reported to decrease the animal's resistance to certain viral infections. The arsenite (+3) and arsenate (+5) forms have different modes of action. Arsenite binds to sulphhydryl groups and has been reported to inhibit over 100 different enzymes, while the arsenate can substitute for phosphate in various high energy intermediates, resulting in arsenolysis. In addition, when arsenate is reduced to arsenite in the body, it can also cause toxicity as that species.  相似文献   

4.
Traw MB  Feeny P 《Ecology》2008,89(3):763-772
Glucosinolates, trichomes, nitrogen, and carbon are not distributed uniformly through the canopies of mustards. In this study, we asked whether glucosinolate concentrations and trichome densities in two sympatric mustards, Brassica kaber and B. nigra, are highest in tissues of greatest value to the plant. We also asked whether nitrogen or carbon content is the stronger predictor of tissue value, and what fraction of each resource is incorporated in glucosinolates. To quantify tissue values, we removed three equal-area fractions (lower, middle, and upper) from the canopies of B. kaber and B. nigra in the greenhouse, as well as whole canopies of naturally growing B. nigra in the field, at two times during growth and measured reductions in their performance relative to controls. We also measured trichome density in both experiments, as well as glucosinolate, nitrogen, and carbon concentrations for the equal-area fractions in the greenhouse. We found that upper leaves had the highest glucosinolate concentrations, trichome densities, and tissue values. Furthermore, young plants in the field had higher trichome densities and tissue values than did older plants. Collectively, these data provide strong support for optimal defense theory and are among the first such evidence for glucosinolates and for physical defenses. The positive relationship between trichome density and tissue value was strong even after we accounted for the effects of leaf expansion. While nitrogen and carbon have both received attention as currencies for trade-offs, our data suggest that nitrogen concentration is a significantly better predictor of tissue value in these two mustard species. Interestingly, <1% of the nitrogen or carbon in leaves was incorporated in glucosinolates, which may explain why glucosinolates lack a consistent response to nitrogen fertilization.  相似文献   

5.
Five week-old mice were divided into a vehicle control group, and groups exposed to ZnO nanoparticles at low (0.5 g/kg), middle (1 g/kg), high (3 g/kg), and exceptionally high-dose (5 g/kg). After the first, second, third, and fourth weeks’ of exposure, blood biochemistry, histopathology, and electron microscopic ultrastructural changes in liver, kidney and spleen were investigated. Increased alkaline phosphatase activities were observed in all treated mice being statistically significant at higher dose. No changes were observed in the serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, creatinine, blood urea nitrogen, and lipid levels. During the first and second weeks of the treatment, effects on the cytoarchitecture of liver, kidney, and spleen were not perceived while during the third and fouth weeks of treatment sporadic mild effects were seen. Ultrastructural electron microscopic changes in liver, kidney, and spleen were not observed for the low-dose group on the first, second, third, and fourth weeks, suggesting that exposure to ZnO nanoparticles at low dose is safe. Long-term (i.e., more than 28 days) exposure to the exceptionally high-dose resulted in sporadic changes in nuclear chromatin condensation, irregular nuclear membrane, polymorphic mitochondria, mitochondrial swelling, and vacuolation. ZnO nanoparticles could be well tolerated and no death occurred in any group of treated mice.  相似文献   

6.
环境中的镉污染对动植物及人类都带来了极大的危害。目前,多数镉毒理研究关注其无机状态,而来源于稻米的有机态镉的毒害作用报道较少。为评估稻米来源镉对生长期猪的毒性作用,选用初始体重为30 kg左右的健康生长猪28头,随机分为体重无明显差异的2组,即对照组与稻米来源镉组(试验组),研究稻米来源镉对生长期猪(生长及育肥全阶段)的生长特性及不同脏器组织镉蓄积的影响。结果表明,在生长及育肥阶段,试验组与对照组相比:1)生长特性无显著差异(P0.05);2)育肥期组织游离氨基酸含量,除肌肉中的赖氨酸显著降低外(P0.05),血浆、肝脏、肾脏及肌肉中其他游离氨基酸水平均无显著差异(P0.05);3)心脏、肝脏、脾脏、肾脏、肺脏、胃、小肠、大肠、骨骼中镉蓄积量显著增高(P0.05),而肌肉、血液中无显著差异(P0.05),脂肪、皮中未检出镉。日粮使用大比例镉超标稻米后镉在各脏器和组织中的蓄积规律为肾脏肝脏小肠脾肺大肠胃血液骨头心腿肌背肌脂肪、皮。由此可见,镉超标稻米对生长期猪的生长特性未产生显著的影响,稻米来源镉主要蓄积于肝脏和肾脏,而主流食用组织肌肉和血液中镉的蓄积量较少。  相似文献   

7.
Histopathological alterations in Nile tilapia, Oreochromis niloticus, aged 3 months and subjected to acute and subchronic alachlor exposure were studied by light microscopy LC50 values of alachlor for 24 hr 48 hr, 72 hr and 96 hr were 963.6, 563, 448, and 381.9 microg l(-1), respectively and the maximum acceptable toxicant concentration (MATC) was 350 microg l(-1). Fish were exposed to 381.9 (acute) and 35 microg l(-1) (sub-chronic) of alachlor for 24, 48, 72 and 96 hr and 90 days, respectively Gill lamellae and kidney tubules were the primary target organs for the acute toxic effect of alachlor while in the subchronic exposure, the toxic effect on the gills was less marked than that of the kidneys and liver Gill alterations included edema of the epithelial cell system, aneurisms with some ruptures, hypertrophy and hyperplasia of epithelial cells. The liver showed hydropic swelling of hepatocytes and vacuolation. Lipid vacuoles were observed in hepatocytes in the second and third month of subchronic exposure. The kidney showed hydropic swelling of tubular cells, lipid vacuole accumulation in many tubules, and nuclear pyknosis. The findings of this study could be used as a guideline forbiomonitoring programs on populations of Nile tilapia cultured near alachlor contaminated areas.  相似文献   

8.
A flue gas desulphurization product based on the absorption of sulphur dioxide by an ammoniacal solution (Am-FGD) was evaluated as a nitrogenous fertilizer. Evaluation was by field trial using barley and rye-grass as test crops. The Am-FGD solution was added to the soil either one week before sowing the barley, at sowing, or one week after. In the grass experiment, the Am-FGD solution was added to the soil surface or sprayed on the plants shortly after the first and after the second cut.The results indicate that nitrogen in the Am-FGD solution had the same fertilizer value as nitrogen in calcium-ammonium-nitrate (CAN). The toxic effect of sulphite is avoided or reduced to insignificant levels when direct contact of the Am-FGD solution with the plants is avoided. When added in combination with CAN there might even be a slight positive effect. The plant content of inorganic elements was unchanged by the experimental treatments.  相似文献   

9.
Prior surveys conducted have found higher proportion of arsenic-contaminated wells in villages along river Indus in Pakistan. This study aims to determine the prevalence of arsenicosis skin lesions among population exposed to higher exposure in taluka Gambat district Khairpur in Sindh. The cross-sectional survey was conducted from August 2008 to January 2009 among 610 households. A total of 707 water sources (hand pumps/wells) were tested from the villages of union councils of Agra and Jado Wahan for arsenic levels with Quick rapid arsenic field test kits. A total of 110 households exposed to arsenic levels >50 ppb were identified. Case screening for arsenic skin lesions was performed for 610 individuals residing in these 110 high-risk households. Information regarding household and socio-demographic characteristics, height and weight measurements and arsenic exposure assessment were collected. Physical examinations by trained physicians were carried out to diagnose the arsenic skin lesions. After data cleaning, 534 individuals from all age groups were included in the final analysis which had complete exposure and outcome information. Overall prevalence of arsenicosis skin lesions was 13.5 % (72 cases). Of the 534 individuals, 490 (91.8 %) were exposed to arsenic levels of ≥100 ppb in drinking water (8.2 % to >50–99 ppb, 58.6 % to 100–299 ppb, 14.6 % to 300–399 ppb and 18 % to ≥400 ppb). Prevalence rate (per 100 population) of arsenicosis was highest at arsenic levels of 100–199 ppb (15.2 cases) followed by ≥400 ppb (13.5 cases) and 300–399 (12.8 cases). Prevalence rate was higher among females (15.2) compared to males (11.3). Our study reports arsenicosis burden due to exposure to higher arsenic levels in drinking water in Pakistan. Exposure to very high levels of arsenic in drinking water calls for urgent action along river Indus. Prevalence of skin lesions increases with increasing arsenic levels in drinking groundwater. Provision of arsenic-free drinking water is essential to avoid current and future burden of arsenicosis in Pakistan.  相似文献   

10.
Comparative hepatic and renal toxicity of cadmium in male and female rats   总被引:3,自引:0,他引:3  
Rats (male and female) were exposed to 0.5 mg/kg and 1 mg/kg cadmium as cadmium chloride for 3 days and subsequently sacrificed for cadmium concentration and other biochemical variables indicative of hepatic and renal damage. The absorption of cadmium was supported by biochemical changes, which were significantly higher in females than in males. This could be due to higher rate of intestinal absorption of cadmium in females than males. Male and female rats both showed relatively higher cadmium concentration in kidneys than in liver. Female rats also showed the similar trend in tissue metal levels as compared to male rats. However, hepatic and renal histopathological observations showed that female rats suffered from severe hepatic injury like hydropic degeneration of hepatocytes, granulation, bile duct proliferation etc. In comparison to female rats, male rats did not show much remarkable changes. Renal damage was more prominent in female than male in the form of renal tubular damage; most of the tubular nuclei were pyknotic, congestion of the boundary of cortex and medulla etc. The results suggested that females were comparatively more vulnerable to the toxic effects of cadmium than males.  相似文献   

11.
The objective of this study was to examine the toxicological effect of two major heavy metal pollutants, lead chloride (PbCl2) and cadmium chloride (CdCl2), in the freshwater climbing perch, Anabas testudineus. Fish were exposed to 1.0 and 2.0 mg/L both metals and histopathological changes in gill, kidney and liver tissues were studied. Major changes observed in gill tissue were epithelial lifting, proliferation of epithelial cells, fusion of secondary lamellae, hyperplasia and hypertrophy of mucous cells, and necrosis of epithelial cells. Cell necrosis, degenerated kidney tubules, congestion, lymphocytic infiltration and vacuolation were the major abnormalities observed in kidney tissue. The most conspicuous changes in liver were darker nucleoli, irregularly shaped hepatocytes with dilated blood capillaries, and focal as well as single necrosis. Fish specimens exposed to PbCl2 exhibited pronounced changes in all tissues examined compared with those exposed to CdCl2. It is evident from this study that heavy metals can cause significant histopathological changes in fish tissue.  相似文献   

12.
Zinc oxide nanoparticles (ZnO2), a common ingredient of cosmetics has a huge variety of applications. Previous studies reported oxidative stress mediated toxicity of ZnO2 nanoparticles on various mammalian cell lines. Although zinc (Zn) is an essential mineral at higher concentrations this metal is toxic. The present study focused on size determination by monitoring changes in activities of antioxidant defense mechanism in response to oxidative stress induced by ZnO2 nanoparticles using mouse liver tissue homogenates. The study also investigated effects of oxidative stress induced DNA damage by determining formation of 8-OHdG in mouse liver homogenate. A cytotoxicity assay was also carried out in L929 cells to determine cell viability. The results of the study indicated that 50μg/ml of ZnO2 nanoparticles induced 50% cell death. Alterations in antioxidant parameters and 8-OHdG were also noted. Data showed that there was a concentration-dependent fall in cell viability, decrease antioxidant enzyme levels and increase formation of DNA adduct (8-OHdG) when mouse liver tissue homogenate were exposed to ZnO2 nanoparticles.  相似文献   

13.
Nodularin (NODLN) is a cyclic pentapeptide hepatotoxin produced by the cyanobacterium Nodularia spumigena, which forms extensive blooms during the summer in the Baltic Sea. Nodularin was detected in liver, muscle and/or feather samples of several common eiders (Somateria mollissima) from the Gulf of Finland (northern Baltic Sea) in 2002–2005. Published information on the adverse effects of NODLN in marine birds is scarce. The aim of this study was to evaluate the toxicity of NODLN, and determine the concentrations of NODLN in liver and muscle tissue in mallards (Anas platyrhynchos) exposed to N. spumigena. Mallards received a single or multiple exposure via oral gavage with an aqueous slurry containing toxic N. spumigena. Dosages ranged from 200 to 600 µg NODLN per kg body weight (bw). There were minimal histopathological changes in liver tissue, and brain cholinesterase activity did not differ among treatment groups. Concentrations of NODLN measured by LC-MS in liver varied between approximately 3–120 µg kg?1 dry weight (dw) and ducks receiving multiple exposures had significantly greater liver toxin levels than ducks receiving the two lowest single exposures. In muscle, NODLN concentrations were approximately 2–6 µg kg?1 dw, but did not differ significantly among exposure groups. This is the first in vivo lab study examining the effects and bioaccumulation of NODLN from N. spumigena in birds. The mallards in this study were resistant to adverse effects and did not bioaccumulate substantial levels of NODLN at the doses given.  相似文献   

14.
Narwhals (Monodon monoceros) from North West Greenland are known to bioaccumulate mercury (Hg) in tissues and internal organs. This is postulated to be a health concern and therefore studies were undertaken to conduct a screening study of Hg concentrations and histopathology of liver and renal tissues in a total of 12 specimens. The sample consisted of two sub-adults (one male, one female) and 10 adult (six males, four females) collected in Qaanaaq (Thule) 2010. In liver, Hg mean ± SD was 11.88 ± 10.47 μg/g ww (range: 0.39?31.8 μg/g ww) while the concentrations in kidneys were 1.85 ± 1.20 μg/g ww (range: 0.41?4.03 μg/g ww). There was no marked difference in Hg concentrations between males and females while sub-adults had significantly lower concentrations. The histological examinations of renal tissue showed glomerular capillary dilatation and basement membrane thickening, dilatation, and hyalinization of Bowman's space/capsule and tubular lesions with hyaline casts accompanied by interstitial fibrosis in the kidneys. In liver tissue, portal cell infiltrates and fibrosis, bile duct proliferation, lipid-filled Ito cells, and steatosis were found. There was no marked difference in histological prevalence between males and females and in Hg concentrations in individuals with or without lesions. Four of seven renal lesions and one liver lesion were found in the two sub-adult whales. Based upon these findings, as well as the nature of the lesions, evidence suggests that histopathological alterations were a result of age but that Hg might be an aggravating co-factor in development of renal lesions in particular.  相似文献   

15.
In this study, the effects of fungicide benomyl and the protective effects of α-lipoic acid (LA) and chondroitin-4-sulfate (C4S) used as antioxidants on liver and kidney of rats were investigated. Benomyl (200 mg kg?1), LA (200 mg kg?1), and C4S (25 mg kg?1) were administered intraperitoneally by injection once a week for a period of five weeks. The results of this study are as follows: benomyl given subchronically showed toxic effects in the form of lipid peroxidation (LPO) on liver and kidney, and LA and C4S had antioxidant effects on liver and kidney. When LA and C4S were applied together, they were more effective than individually. Furthermore, it was observed that LA and C4S had partial protective effects against the histopathological effects caused by benomyl.  相似文献   

16.
为探讨甲醛、苯、甲苯及二甲苯混合气体急性暴露对小鼠肺脏的氧化损伤作用,选用雄性健康昆明种小鼠50只,随机分为对照组和4个染毒组。染毒组1到4中甲醛、苯、甲苯和二甲苯浓度依次为:1.0+1.1+2.0+2.0μg·L-1、3.0+3.3+6.0+6.0μg·L-1、5.0+5.5+10.0+10.0μg·L-1、10.0+11.0+20.0+20.0μg·L-1,各染毒组混合气体的浓度分别是我国室内空气质量标准(GB/T18883-2002)的10、30、50和100倍。用静式吸入染毒方式,每天染毒2h,共染毒10d,实验结束后,测定小鼠肺脏中的氧化损伤指标。结果表明:染毒组小鼠的体重增加幅度均低于对照组,肝脏和脾脏系数显著低于对照组,肺脏ROS、MDA含量随染毒剂量的增加而增加,T-AOC、GSH、CAT、GSH-Px及SOD活力随染毒剂量的增加而降低,并且ROS、MDA含量与混合气体的浓度呈显著的正相关关系,GSH含量与混合气体的浓度呈显著的负相关关系。研究结果显示,甲醛、苯、甲苯及二甲苯混合气体急性暴露对小鼠肺脏具有氧化损伤作用,混合气体的联合毒性效应强于单一组分,ROS、MDA和GSH可以作为评价VOCs急性暴露对机体氧化损伤作用的敏感生物学标志。  相似文献   

17.
The study investigated the effect of calcium (Ca) supplementation on lead-induced toxicity in suckling male Wistar rats. The sucklings were exposed to lead acetate (5 mg/kg b wt./week) orally for a period of six weeks. The unexposed group of sucklings was the negative control. Out of the lead-exposed groups, two groups were supplemented with Ca at 3% and 6% as CaHPO4 × 2H2O in suspension in cow's milk. The artificial feeding regimen was followed for 7 h each day for 6 weeks. Sucklings exposed to lead with Ca supplementation recorded a significantly higher increase in body weight and a significant reduction of lead concentration in all tissues. The lead-induced histopathological alterations in the liver and kidney were also reversed with Ca supplementation. Sodium rhodizonate staining of liver sections showed distinct presence of lead granules in the group exposed to lead while the Ca-supplemented groups were comparable to the control. Lead exposure reduced the expression of rad 51 in the testis and liver which was markedly enhanced with Ca supplementation and was restored to the level in the control. Thus, Ca supplementation during the suckling period was effective in ameliorating the lead-induced toxicity.  相似文献   

18.
为探讨纳米二氧化硅(Nano-SiO2)、纳米四氧化三铁(Nano-Fe3O4)和单壁碳纳米管(SWCNTs)对大鼠肝、肾的毒性效应,将49只雄性Wistar大鼠随机分为7组,包括生理盐水对照组,以及3种纳米材料的低剂量组(2mg·mL-1)和高剂量组(10mg·mL-1),采用非暴露式气管滴注法染毒,每2d染毒1次,每次每只0.2mL,共染毒5周,眼眶取血后处死大鼠,称肝、肾重量计算脏器系数,测定大鼠血清中反映肝、肾功能的生化指标,并对肝、肾进行病理学观察.结果表明,1)3种纳米材料均可导致大鼠体重明显降低,但对肝、肾脏器系数无明显影响;2)病理学观察发现,3种纳米材料均可导致大鼠肝细胞轻度脂肪变性,肾脏则无明显改变;3)3种纳米材料均可导致大鼠肝功能异常,部分肝功能指标如谷草转氨酶(AST)、碱性磷酸酶(ALP)、谷丙转氨酶(ALT)等出现显著降低;4)3种纳米材料均可导致大鼠肾功能异常,部分肾功能指标如尿酸(UA)、肌酐(CREA)、尿素氮(BUN)等出现显著升高或降低.以上结果提示,经呼吸道染毒的Nano-SiO2、Nano-Fe3O4和SWCNTs均可对大鼠肝、肾产生一定的毒性效应.  相似文献   

19.
硫酸锰废渣浸出液对斑马鱼的毒性及抗氧化酶活性的影响   总被引:1,自引:0,他引:1  
已有研究表明,堆积在湘西花垣河河岸的硫酸锰废渣含有多种重金属,可能是导致花垣河河水和沉积物重金属污染的主要原因.为了评价硫酸锰废渣的潜在生态风险和对水生动物的毒性,本研究分析了硫酸锰废渣浸出液中的主要重金属成分,用漫出液对斑马鱼进行了急性毒性实验,观察在急性胁迫下斑马鱼的体征变化,测定了斑马鱼在亚致死浓度下的生化指标的...  相似文献   

20.
为研究铅、镉联合暴露对公鸡生长早期的生殖毒性,150只1日龄雄性AA(爱拨益加)肉鸡被随机分成5组:C、T1、T2、T3和T4,每组6个重复,每重复5只,分别饲喂基础日粮及基础上添加10 mg·kg-1铅+2 mg·kg-1镉、10 mg·kg-1铅+50mg·kg-1镉、100 mg·kg-1铅+2 mg·kg-1镉...  相似文献   

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