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《Pesticide biochemistry and physiology》2004,79(2):58-63
The effects of exposure of human erythrocytes to different concentrations of Roundup Ultra 360 SL and its active compound glyphosate were studied. We studied hemolysis after 1, 5, and 24 h incubation; lipid peroxidation, hemoglobin oxidation, the level of reduced glutathione, and the activity of catalase after 1 h. Human erythrocytes were incubated with 100-1500 ppm (100 μg/ml erythrocytes at 5% hematocrite) Roundup Ultra 360 SL and glyphosate. We have found that after 1 h of incubation only Roundup Ultra 360 SL increased the level of methemoglobin, products of lipid peroxidation at 500 ppm and hemolysis at 1500 ppm [Curr. Top. Biophys. 26 (2002) 245], while its active compound glyphosate increased the level of methemoglobin and the level of lipid peroxidation at much higher dose—1000 ppm. At the same time hemolysis was observed to only at the highest dose of glyphosate (1500 ppm) and the longest time of incubation (24 h). Both Roundup Ultra 360 SL and glyphosate did not cause statistically significant changes in the level of GSH, but increased the activity of catalase. Roundup Ultra 360 SL provokes more changes in the function of erythrocytes than its active substance glyphosate, which is probably a result of the properties of additives. Taking into account the limited accumulation of Roundup Ultra 360 SL and glyphosate in the organism as well as the fact that the threshold doses which caused changes in erythrocytes for Roundup Ultra 360 SL were only 500 and 1000 ppm for glyphosate, one may conclude that this pesticide is safe towards human erythrocytes. 相似文献
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The objective of this study was to assess the influence of an asymptomatic experimental infection by Babesia bigemina on cholinesterase’s as markers of the inflammatory process and biomarkers of oxidative imbalance. For this purpose, eight naive animals were used, as follows: four as controls or uninfected; and four infected with an attenuated strain of B. bigemina. Blood samples were collected on days 0, 7 and 11 post-inoculation (PI). Parasitemia was determined by blood smear evaluation, showing that the infection by B. bigemina resulted in mean 0.725 and 0.025% on day 7 and 11 PI, respectively, as well as mild anemia. The activities of acetylcholinesterase, butyrylcholinesterase and catalase were lower, while levels of thiobarbituric acid reactive substances and superoxide dismutase activity were higher in infected animals, when compared with the control group. This attenuated strain of B. bigemina induced an oxidative stress condition, as well as it reduces the cholinesterasés activity in infected and asymptomatic cattle. Therefore, this decrease of cholinesterase in infection by B. bigemina purpose is to inhibit inflammation, for thereby increasing acetylcholine levels, potent anti-inflammatory molecules. 相似文献
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AIM:To study the effect of VEGF on extracellular H2O2 production in HUVECs and the role of H2O2 in the VEGF-induced proliferation. METHODS:HUVECs was stimulated with 500 μg/L VEGF. Products of extracellular H2O2 was detected by H2DCFDA staining. MTT method was used to value the influences of 3×106 U/L catalase and 5-20 mmol/L H2O2 to VEGF function. RESULTS:After treatment for 15 min with VEGF, HUVECs appeared fluorescence, and continued to become stronger, peaked at 45 min then decreased. HUVECs, which was treated simultaneity with VEGF and 3×106 U/L catalase, only appeared very faint fluorescence. The proliferation of HUVECs by VEGF was restrained when treated with 3×106 U/L catalase. The extrinsic H2O2 at concentration of 5-10 mmol/L promoted the proliferation of HUVECs but inhibited the proliferation effect of VEGF on HUVECs (P<0.01). CONCLUSION:These findings indicate that VEGF induces HUVECs to produce extracellular H2O2 and plays role in proliferation, but extrinsic H2O2 restrains VEGF function. 相似文献
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有机肥对水分胁迫下大豆几种生理指标和茎叶组织超微结构的影响 总被引:4,自引:2,他引:2
1993-1994年在碳酸盐黑钙土上进行了有机肥,化肥和有机无机配合施用的盆栽试验。在大豆生育期间人工模拟旱境条件下测定了与大豆抗旱性有关的大豆叶片细胞膜透性,过氧化氢酶活性,内源激素脱落酸含量和茎叶组织超微结构等项目。 相似文献
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The aim of this greenhouse experiment was the assessment of the influence of H2SeO3 at soil concentrations of 0.05, 0.15 and 0.45 mmol kg−1, on the activity of selected oxidoreductive enzymes in wheat (Triticum aestivum). The wheat plants were grown in 2 dm3 pots filled with dust-silt black soil of pH 7.7. Applied H2SeO3 caused activation of plant nitrate reductase at all concentrations, but activation of plant polyphenol oxidase at only two lower concentrations. The highest concentration caused inhibition of polyphenol oxidase and peroxidase. Plant catalase activity decreased under the influence of 0.15 and 0.45 mmol kg−1 concentration. After the final analysis Se was quantified in plants and soil. The amounts in plants were: control (unamended soil) 1.95 mg kg−1; I dose (0.05 mmol kg−1) 18.27 mg kg−1; II dose (0.15 mmol kg−1) 33.20 mg kg−1 and III dose (0.45 mmol kg−1) 38.37 mg kg−1, in soil: 0.265 mg kg−1; 3.61 mg kg−1; 10.53 mg kg−1; 30.53 mg kg−1; respectively. Simultaneously, a laboratory experiment was performed, where the activity of soil catalase and peroxidase were tested after 1, 3, 7, 14, 28, 56, and 112 days after Se treatment. Peroxidase activity in soil decreased with increasing Se content, over the whole experiment. The lowest dose of Se caused activation a significant 10% increase in catalase activity, but the influence of others doses was unclear. 相似文献
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镉对小麦苗期生长及生理指标的影响 总被引:2,自引:0,他引:2
[目的]了解镉对小麦生长的毒害作用。[方法]采用溶液培养的方法,研究不同浓度的金属镉对淮麦18生长及生理特性的影响。[结果]低浓度镉(≤0.10 mmol/L)对小麦生长有一定的促进作用,高浓度镉(>0.10 mmol/L)则有抑制作用。采用低浓度镉处理的小麦根系活力、叶片叶绿素含量高于对照,当镉浓度上升到0.20和0.30 mmol/L时其活力和含量明显下降。当小麦受到镉轻度胁迫(0.05 mmol/L)时,小麦CAT活性大幅升高,当镉浓度提高到0.10 mmol/L时,CAT活性有所下降,此后CAT活性随浓度的变化趋向平缓。细胞膜透性、MDA含量随着镉浓度的加大和毒害时间的延长逐渐变大。[结论]该研究可为实现对镉污染的预测与评价,防止镉的危害,保证农产品产量、品质提供参考依据。 相似文献
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