Toxic effect of nickel on hemoglobin concentration of Limnodrilus hoffmeisteri in spiked sediments of trout farms

Toxicity and uptake data for Limnodrilus hoffmeisteri generated by nickel in systems using three natural sediments (trout farms: El Oyamel, El Truchón, and El Potrero), are presented. Nickel uptake and hemoglobin concentration were studied in L. hoffmeisteri exposed to spiked sediments. Nickel concentration and its toxic effect on hemoglobin were used as indicators of exposure. Sediment texture was also considered. Hemoglobin concentration decreased after treatment with nickel. The hemoglobin concentration test indicated a response to the bioavailability of nickel. This investigation clearly documents that sediments of El Truchón, El Oyamel, and El Potrero exhibit a toxicity potential. These results suggest the usefulness of diversity of bioassays for evaluating the toxicity of sediments polluted with heavy metals.     

Pyrene bioaccumulation, effects of pyrene exposure on particle-size selection, and fecal pyrene content in the oligochaete Limnodrilus hoffmeisteri (Tubificidae, Oligochaeta)

The oligochaete Limnodrilus hoffmeisteri Cleparéde was exposed to sediment-amended pyrene (0-1,196 nmol/g dry wt) for 2, 5, and 10 d to investigate sediment particle-size preference, tissue pyrene bioaccumulation (using biota-sediment accumulation factor, BSAF), fecal pyrene concentrations (using fecal-sediment accumulation factor, FSAF), and pyrene biotransformation. In non-pyrene-amended sediment, L. hoffmeisteri preferentially ingested finer sediment particles (< 3.5 microns). However, pyrene concentrations > 199 nmol/g dry weight resulted in a decreased preference for finer particles, presumably reducing pyrene exposure. Particle selectivity also changed with time such that after 10 d, worms showed an increased preference for finer particles. At high pyrene exposure, tissue pyrene concentrations rapidly attained equilibrium (maximum body residue 4.4 mumol/g wet wt, close to values cited for hydrocarbon critical body residues). Levels of biotransformation were low (mean 14%) and independent of time or pyrene concentration. Biota-sediment accumulation factor showed a negative relationship with sediment pyrene concentration; this trend may be due to reduced availability at high sediment pyrene concentrations or due to reductions in both ingestion rate and selectivity for fine, pyrene-rich particles. Fecal pyrene concentrations were depleted compared to sediment levels, suggesting removal of pyrene during gut passage by absorption. Fecal-sediment accumulation factor showed a negative relationship with increasing sediment pyrene levels.     

还原型谷胱甘肽对六价铬诱导的L-02肝细胞毒性的保护作用

目的探讨还原型谷胱甘肽(GSH)对六价铬[Cr(Ⅵ)]诱导的L-02肝细胞毒性的影响。方法分别设Cr(Ⅵ)、GSH单独作用组、联合作用组和空白对照组,采用MTT法检测细胞生存率的变化。结果在2、4、8、16、32和64μmol/LCr(Ⅵ)处理浓度,Cr(Ⅵ)对L-02肝细胞具有明显细胞毒性,细胞存活率与Cr(Ⅵ)处理浓度呈负相关(r=-0·910)。仅浓度为20μmol/L的GSH对Cr(Ⅵ)诱导的细胞毒性具有拮抗作用,Cr(Ⅵ)+GSH联合组的生存率与Cr(Ⅵ)不同浓度单独处理组比较差异均具有显著性(P<0·05)。结论适宜浓度的GSH可能对Cr(Ⅵ)诱导的L-02肝细胞毒性具有保护作用。     

枸杞对铬（VI）损伤的修复研究

目的：了解铬（VI）对小鼠体质量和脏器系数的影响,探讨枸杞对由铬（VI）损害的修复作用。方法选择昆明种小鼠60只,随机分为对照组、重铬酸钾组、重铬酸钾＋枸杞组,共3组,分别给予正常进食,7．5 g／L重铬酸钾水溶液和7．5g／L重铬酸钾＋50mg／L枸杞溶液,采用经口灌胃染毒,每日一次,连续7d。末次染毒24h后,测定小鼠体质量和主要脏器质量,计算脏器系数,统计分析。结果①雌性小鼠体质量、各主要脏器质量及脏器系数在3组间比较结果,体质量、心、肝、脾、肺、肾的质量及脾的脏器系数均有统计学意义（P＜0．05）,其余指标间无统计学意义（P＞0．05）。②雄性小鼠体质量、各主要脏器质量及脏器系数在3组间比较结果,脾、睾丸的质量及脏器系数均有统计学意义（P＜0．05）,其余指标间无统计学意义（P＞0．05）。③同组别内,不同性别小鼠体质量、各主要脏器质量及脏器系数比较结果,对照组内,雌雄小鼠体质量、脾脏质量及脏器系数、肺脏脏器系数、肾脏质量及脏器系数均有统计学差异（P＜0．05）,其余指标间无统计学差异（P＞0．05）;重铬酸钾组内,雌雄小鼠体质量、心、肝、脾、肾脏质量均有统计学差异（P＜0．05）,其余指标间无统计学差异（P＞0．05）;重铬酸钾＋枸杞组内,雌雄小鼠体质量、脾脏质量及脏器系数、肺脏脏器系数、肾脏质量均有统计学差异（P＜0．05）,其余指标间无统计学差异（P＞0．05）。结论 Cr（VI）引起小鼠的脾脏损伤,对雄性小鼠的睾丸也具有损伤作用,枸杞可拮抗铬所致的小鼠损伤。     

不同糖化血红蛋白水平对糖尿病患者颈动脉内皮细胞功能的影响

目的研究糖尿病患者不同糖化血红蛋白（HbA1c）水平对颈动脉内皮细胞功能的影响。方法选取2型糖尿病患者120例,根据HbA1c水平分组,6％≤HbA,C〈7％为第1组（30例）,7％≤HbA1c〈8％为第2组（31例）,8％≤HbA1c〈9％为第3组（29例）,HbA1c≥9％为第4组（30例）。分别进行血管内皮功能指标的检测以及颈动脉彩色多普勒超声检查并记录。结果四组血管内皮功能指标内皮素1（ET-1）与一氧化氮（NO）比较差异有统计学意义（P〈0．01）,两两比较,第4组ET-1与NO最高[（89．34±19．2）ng／L、（59．5±9．3）μmol／L],其次为第3组[（85．9±16．4）ng／L、（56．44±8．9）μmol／L]和第2组[（83．44±17．3）ng／L、（52．3±8．3）μmol／L],差异有计学意义（P〈0．05）。四组颈动脉内膜-中层厚度（IMT）比较差异有统计学意义（P〈0．01）,两两比较,第4组颈动脉IMT最大[（2．90±0．62）mm],其次为第3组[（2．40±0．73）mm]和第2组[（1．90±0．42）mm],差异有统计学意义（P〈0．05）;四组颈动脉斑块总检出率比较差异有统计学意义（JP〈0．01）,两两比较,第4组颈动脉斑块总检出率最高[93．3％（28／30）],其次为第3组[79．3％（23／29）]和第2组[61．3％（19／31）],差异有统计学意义（P〈0．05）。四组颈动脉斑块分型比较差异有统计学意义（X^2=51．10,P〈0．01）,HbA1c与颈动脉斑块分型之间存在一定的相关性（r=0．56,P〈0．01）。结论2型糖尿病患者HbA1e水平和颈动脉内皮细胞功能与斑块之间存在较强的联系。     

Combined effects of algal (Chlorella vulgaris) density and ammonia concentration on the population dynamics of Ceriodaphnia dubia and Moina macrocopa (Cladocera)

Ammonia is a natural variable in ponds and lakes. Although an important source of nitrogen for microalgae, at high concentrations ammonia can affect the density and diversity of cladocerans. Using the cladocerans Ceriodaphnia dubia, and Moina macrocopa, the effect of nominal concentrations of ammonium chloride under acute and chronic exposures at different levels of algal food was tested. Regardless of food level, C. dubia was more sensitive than M. macrocopa to ammonia. In the absence of food, the median lethal concentration of ammonia (LC(50) 24 h) for C. dubia was (112 mg L(-1)) less than half that of M. macrocopa (232 mg L(-1)). When algal food (0.5 x 10(6) and 1.5 x 10(6) cells ml(-1) of Chlorella) was used, the LC(50) values were much higher for both cladoceran species. Based on the population growth studies, it was found that in controls of M. macrocopa an increase in the availability of Chlorella from 0.5 to 1.5 x 10(6) cells mL(-1) led to an increase in the maximum density from 4.7 +/- 0.2 to 16.4 +/- 1.2 ind.mL(-1), while in C. dubia the peak population density decreased from 7.9 +/- 0.6 to 5.0 +/- l.0 ind.mL(-1). An increase in ammonia concentration (10 to 40 mg L(-1) for C. dubia and 20 to 120 mg L(-1) for M. macrocopa) resulted in a corresponding decrease in peak population densities of the tested cladocerans. The rate of population increase (r) values for M. macrocopa in the controls ranged from 0.21 +/- 0.001 and 0.25 +/- 0.02 at 0.5 and 1.5 x 10(6) cells mL(-1) of Chlorella, respectively. The corresponding values of C. dubia in controls were 0.21 +/- 0.004 and 0.18 +/- 0.01. At 0.5 x 10(6) cells mL(-1) of algal food, the r values became negative under 40 and 120 mg L(-1) of ammonia for C. dubia and M. macrocopa, respectively. The role of algal food in ammonia toxicity to cladocerans was discussed. (c) 2002 Elsevier Science (USA).     

无机铬复合物对实验性糖尿病小鼠血糖和肝糖原水平的影响

采用葡萄糖氧化酶法观察口服无机铬复合物 (Cr3 +10 μg/kg体重每日 )对实验性糖尿病小鼠血糖水平的影响。与实验前相比血糖有明显下降 ,差异显著 (P <0 0 5 ) ,与糖尿病对照组相比差异极为显著 (P <0 0 1)。无机铬溶液 (Cr3 +10 μg/kg体重每日 )喂养组与实验前相比血糖有明显下降 ,差异显著 (P <0 0 5 ) ,与糖尿病对照组比较差异显著 (P <0 0 5 )。无机铬复合物实验组肝糖原含量与糖尿病对照组相比明显增高 (P<0 0 5 )。     

富铬酵母对实验性糖尿病小鼠胰岛影响的免疫组织化学观察

目的 :采用 HRP- SPA法研究了富铬酵母对实验性糖尿病小鼠胰岛及 B细胞形态结构的影响。方法 :将糖尿病小鼠随机分为 3组 :糖尿病对照组、实验 组 (富铬酵母 2 5 0 μg/kg·d)、实验 组 (富铬酵母 1 2 5 μg/kg·d) ,另设正常对照组 ,实验周期为 4周。结果 :实验动物胰岛内空虚部分明显缩小 ,B细胞及其颗粒增多 ,界限较清。结论 :富铬酵母对实验性糖尿病小鼠受损胰岛及 B细胞形态结构具有明显的改善作用     

锰 铬对体外培养小鼠卵母细胞减数分裂的影响

采用卵母细胞体外培养的方法 ,研究了硫酸锰、氯化铬对小鼠卵母细胞的成熟和减数分裂的影响。结果表明 ,二者均能抑制体外培养卵母细胞的第一极体释放 ,降低体外培养卵母细胞的存活率 ,在培养 8h时都能够抑制卵母细胞的生发泡破裂。实验结果还显示 ,氯化铬比硫酸锰对卵母细胞的损伤作用更大。提示 ,硫酸锰和氯化铬都可以破坏卵母细胞的成熟和减数分裂 ,有明显的生殖毒性。     

诺和龙对糖尿病患者餐后血糖、血脂及对糖化血红蛋白的影响

目的探讨诺和龙对糖尿病患者餐后血糖、血脂及对糖化血红蛋白的影响。方法分析该院187例初诊2型糖尿病患者,随机分为治疗组96例给予诺和龙,对照组91例给予二甲双胍。比较两组餐后2h血糖(hPG)、糖化血红蛋白(HbA1c)、TC(血清总胆固醇),TG(血清甘油三酯)变化情况。结果治疗前两组2hPG、HbA1c、TC,TG水平变化无显著性意义(P>0.05)。治疗后两组2hPG、HbA1c、TC,TG水平变化具有显著性意义(P<0.05)。结论诺和龙治疗糖尿病疗效确切,值得临床推广使用。     

The effect of hexavalent chromium on the critical thermal maximum and body burden ofClioperla clio (Plecoptera:Perlodidae)

Clioperla clio (Plecoptera:Perlodidae) nymphs exposed to eight levels of hexavalent chromium experienced 0.03% (control) to 76.0% lethality after 96 hr at 9.0°C and had an LC50 of 101.3 mg/L (95% C.I.=88.9 – 118.1 mg/L). Nymphs exposed to sublethal levels of Cr⁺⁶ in EPA hardwater at 9.0°C had statistically significant reduction in upper temperature tolerance measured as critical thermal maximum (CTM_CONTROL > > , range 31.46–29.49°C). The ecological death endpoint criterion resulted in low variability for controls (C.V.=2.4%). Exposed nymphs digested with nitric acid had mean body burdens ranging from 1.37 (g total Cr/g dry weight) for those exposed to 5.25 mg/L, to 26.71 for the 143.25 mg/L exposure group. As Cr⁺⁶ exposure increased, body burden of nymphs increased linearly, and CTM significantly decreased. Since the 96-hr LC50 greatly exceeds Cr⁺⁶ measured in the field and the critical thermal maxima are at least 10°C greater than the adult emergence temperature, it is unlikely that environmentally realistic combinations of Cr⁺⁶ and temperatures will have adverse impacts on mature nymphs ofClioperla clio in nature if adverse conditions are of short duration.     

葡萄糖酸铬对体外高糖培养乳鼠心肌细胞保护作用

目的:探讨葡萄糖酸铬对体外高糖培养乳鼠心肌细胞的保护作用及其机制。方法:Wistar乳鼠原代细胞随机分为空白对照组、高糖组及葡萄糖酸铬高、低剂量组。用荧光显微镜测定各组细胞凋亡情况。结果:经葡萄糖酸铬干预后,心肌细胞存活率明显增高,凋亡细胞明显减少,bcl-2表达增加,caspase-3表达减少。结论:葡萄糖酸铬抑制体外高糖培养的心肌细胞凋亡,增高细胞存活率,其机制可能与抑制caspase-3、激活bcl-2表达有关。     

Effects of low levels of lead on growth and reproduction of the Asian earthworm Perionyx excavatus (Oligochaeta)

The effects of sublethal concentrations of lead nitrate on growth and reproduction of the Asian composting earthworm species Perionyx excavatus was studied experimentally by exposing worms in an organic substrate to lead nitrate-contaminated food over a period of 76 days. The results revealed that growth was affected negatively by the presence of lead while maturation rate and cocoon production was not affected. In agreement with other studies on Eisenia fetida, cocoon viability was affected negatively by lead, making this a sensitive toxicity endpoint. Lead accumulation was of the same order of magnitude as for other previously studied species.     

The effect of different contraceptive treatments on the serum concentration of dehydroepiandrosterone sulfate

Twenty-six healthy, non-hirsute women had antecubital venous blood obtained before and during treatment with various contraceptive steroids for the measurement of dehydroepiandrosterone sulfate (DHEA-S). Six of the women were randomized to receive Ortho Novum 1/35 (O/N), 7 were assigned to Ovcon 35 (OV), and another five received Nordette (N). The 6 women ingesting O/N as well as the 7 receiving OV had significant decreases in serum concentrations of DHEA-S (p < 0.05). The percentage of decrease in DHEA-S in the O/N group (39 ± 6%) and in the OV group (30 ± 5%) was not statistically different. The group receiving N showed no changes from baseline measurements. Serum samples from another 8 women who had received subcutaneous implants of levonorgestrel (1-Ng) were obtained. No significant changes occurred in serum DHEA-S between baseline and six-month samples.The data that 1-Ng alone and the combination of 1-Ng and ethinylestradiol did not change DHEA-S levels suggest that 1-Ng does not affect adrenal androgen secretion. Because N, O/N and OV contain similar quantities of ethinylestradiol, these results indicate that norethindrone, but not 1-Ng, has a major suppressive effect upon adrenal androgen secretion.     

The relationship between lysosomal biomarker and organismal responses in an acute toxicity test with Eisenia Fetida (Oligochaeta) exposed to the fungicide copper oxychloride

The LC50 of copper oxychloride for Eisenia fetida was determined, and its effects on biomass change and lysosomal damage using neutral red retention times (NRRT) of coelomocytes were measured. The aim was to establish whether a lysosomal subcellular response, measured as NRRT, could be linked to the LC50 and biomass changes. Further, we attempted to establish the ecological relevance of the LC50 by comparing it to studies previously carried out on the effects of copper oxychloride on field earthworm populations. The experiment was conducted over a period of 28 days, during which the earthworms were exposed to different concentrations of copper oxychloride in artificial soil. The calculated LC50 was 883 microg g(-1) for copper oxychloride and 519 microg g(-1) for copper. Results indicated that changes in coelomocyte membrane stability manifested earlier than effects on biomass. Since the NRRT assay was very sensitive and generated an early response before changes in biomass or mortality could be measured, it may have predictive value and may contribute information during acute toxicity tests, which could be of greater ecological relevance than mortality data alone.     

The influence of exposure history to lead on the lysosomal response in Eisenia fetida (Oligochaeta)

In this study groups of the epigeic earthworm species Eisenia fetida were exposed experimentally for different periods to sublethal concentrations of Pb(NO3)2. The lysosomal membrane fragility response of coelomocytes was used as a biomarker to explore the cytotoxity of Pb by determining the neutral red retention times (NRRTs) and correlating them with different body loads of Pb. Previously unexposed worms exposed to different low concentrations of Pb(NO3)2 for 4 weeks demonstrated a clear dose-response relationship between NRRTs and body burdens of Pb. The NRRTs of growing worms with a previous (ancestral) exposure history, exposed to an elevated concentration of Pb and measured over time, fluctuated around a mean of 41 min and no dose-related relationship could be demonstrated. Worms with a long-term history of exposure to Pb of more than 36 months had a mean body burden of 177.5 +/- 61.5 mg/kg Pb and a mean NRRT of 57.8 +/- 3.1 min, which was significantly lower than that of uncontaminated, control worms with a mean time of 61.9 +/- 3.4 min and a mean body burden of 86.3 +/- 47.2 mg/kg. No significant differences were found between weight changes of "clean" and preexposed worms when they were experimentally exposed to sublethal concentrations of Pb. This study provided evidence that the lysosomal biomarker response for Pb may not persist at the same level in worms with a previous history of Pb exposure, possibly making it less sensitive as a tool for comparing responses to Pb in field populations of earthworms.     

三氯异氰尿酸对大鼠的亚慢性毒性

将SD大鼠按性别、体重随机分为高剂量组(1/8LD50)、中剂量组(1/16 LD50)、低剂量组(1/64LD50)和阴性对照组,分别喂饲相应的受试物饲料90 d,观察大鼠体重、血常规、尿常规、血清生化、脏体系数和组织病理学变化。结果与对照组相比,高剂量组雌性大鼠在染毒第70 d后生长明显减缓并持续到实验结束,AST、ALT活性明显升高;雄性大鼠睾丸脏体系数明显增大,AST、BUN显著升高。中剂量组雄性大鼠AST、BUN也明显增高。低剂量组各指标变化不明显。各剂量组脏器组织未见明显异常改变。提示三氯异氰尿酸原药对动物体重增长有抑制作用,对肝、肾功能有不良影响。经口染毒的亚慢性毒性阈剂量雌雄大鼠分别为99.25、49.62 mg/kg,最大无作用剂量雌雄大鼠分别为49.62、12.41 mg/kg。     

Evaluation of the effect of implanted depleted uranium on male reproductive success, sperm concentration, and sperm velocity

Depleted uranium (DU) projectiles have been used in battle in Iraq and the Balkans and will continue to be a significant armor-penetrating munition for the US military. As demonstrated in the Persian Gulf War, battle injury from DU projectiles and shrapnel is a possibility, and removal of embedded DU fragments from the body is not always practical because of their location in the body or their small size. Previous studies in rodents have demonstrated that implanted DU mobilizes and translocates to the gonads, and natural uranium may be toxic to spermatazoa and the male reproductive tract. In this study, the effects of implanted DU pellets on sperm concentration, motility, and male reproductive success were evaluated in adult (P1) Sprague-Dawley rats implanted with 0, 12, or 20, DU pellets of 1x2 mm or 12 or 20 tantalum (Ta) steel pellets of 1x2 mm. Twenty DU pellets of 1x2 mm (760 mg) implanted in a 500-g rat are equal to approximately 0.2 pound of DU in a 154-lb (70-kg) person. Urinary analysis found that male rats implanted with DU were excreting uranium at postimplantation days 27 and 117 with the amount dependent on dose. No deaths or evidence of toxicity occurred in P1 males over the 150-day postimplantation study period. When assessed at postimplantation day 150, the concentration, motion, and velocity of sperm isolated from DU-implanted animals were not significantly different from those of sham surgery controls. Velocity and motion of sperm isolated from rats treated with the positive control compound alpha-chlorohydrin were significantly reduced compared with sham surgery controls. There was no evidence of a detrimental effect of DU implantation on mating success at 30-45 days and 120-145 days postimplantation. The results of this study suggest that implantation of up to 20 DU pellets of 1x2 mm in rats for approximately 21% of their adult lifespan does not have an adverse impact on male reproductive success, sperm concentration, or sperm velocity.     

Monitoring of chromium and nickel in biological fluids of stainless steel welders using the flux-cored-wire (FCW) welding method

Objective: This study was undertaken to investigate the exposure to chromium (Cr) and nickel (Ni) in flux-cored wire (FCW) welders welding on stainless steel (SS). Method/design: Seven FCW welders were monitored for 3 days to 1 workweek, measuring Cr and Ni in air, blood, and urine. The welders were questioned about exposure to Cr and Ni during their whole working careers, with emphasis on the week of monitoring, about the use of personal protective equipment and their smoking habits. Results: The air concentrations were mean 200 g/m³ (range 2.4–2,744) for total Cr, 11.3 g/m³ (<0.2–151.3) for Cr^VI, and 50.4 g/m³ (<2.0–416.7) for Ni during the workdays for the five welders who were monitored with air measurements. The levels of Cr and Ni in biological fluids varied between different workplaces. For Cr in whole blood, plasma, and erythrocytes, the mean levels after work were 1.25 (<0.4–8.3) and 1.68 (<0.2–8.0) and 0.9 (<0.4–7.2) g/l, respectively. For Ni most of the measurements in whole blood and plasma were below the detection limits, the mean levels after work being 0.84 (<0.8–3.3) and 0.57 g/l (<0.4–1.7), respectively. Mean levels for Cr and Ni in the urine after work were 3.96 (0.34–40.7) and 2.50 (0.56–5.0) g/g creatinine, respectively. Conclusion: Correlations between the Cr^VI levels measured in air and the levels of total Cr in the measured biological fluids were found. The results seem to support the view that monitoring of Cr in the urine may be versatile for indirect monitoring of the Cr^VI air level in FCW welders. The results seem to suggest that external and internal exposure to Cr and Ni in FCW welders welding SS is low in general.