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硒对铅暴露致神经损伤的拮抗作用研究 总被引:1,自引:0,他引:1
目的:研究铅暴露诱导的神经毒性损伤作用,明确铅暴露引发神经毒性损伤的部分机制以及硒的保护作用。方法:通过哺乳期染铅及补充硒建立铅暴露动物模型;通过TUNEL实验确定铅暴露引发的神经损伤;通过Western blot实验检测Bax、Bcl-2、Caspase-3水平确定铅暴露对凋亡途径的启动;并确证补硒在铅神经毒性作用下对机体的保护作用。结果:1.哺乳期铅暴露能够引起仔鼠海马神经细胞凋亡的发生;2.铅暴露能够诱导Bax/Bcl-2水平改变,激活Caspase-3。3.同时给予硒干预后,机体抗铅神经毒性能力显著增加。结论:1.铅暴露能够诱导海马部位神经毒性损伤,损伤可能通过启动凋亡途径而发生,2.补硒能够通过拮抗凋亡发生从而拮抗铅的神经毒性,产生保护作用。 相似文献
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从铅对睾丸与附睾形态、精子生成和发育以及生殖内分泌功能等三方面的影响综述了铅对雄性生殖毒性的研究进展;并从铅对睾丸的脂质过氧化损伤,对睾丸标志酶活性的影响,对染色体、DNA及基因的影响以及对CaM、Ca2 -ATP酶活性的影响等方面探讨了铅对雄性生殖毒性作用机理。同时,提出了铅对雄性生殖毒性的研究中存在的若干问题和发展方向。 相似文献
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单一与复合污染条件下两种敏感性植物对Cd、Zn、Pb的吸收 总被引:7,自引:0,他引:7
为了进一步研究镉、锌、铅3种重金属元素间的相互作用以及对植物吸收重金属能力的影响,在模拟单一重金属污染试验研究的基础上,采用正交回归设计方案.研究了Cd、Zn、Pb复合污染情况下紫花苜蓿和披碱草两种敏感性植物对3种重金属的吸收效应。结果表明,在单一污染条件下.银元素对紫花苜蓿生长的影响大于锌、镉、铅元素对披碱草生长的影响大于锌、镉,紫花苜蓿对于镉的吸收累积显著高于:披碱草,植物内银元素浓度最高达到1088.5mg/kg。而披碱草对于铅元素的吸收则高于紫花苜蓿。植物内铅元素浓度最高达到1345.5mg/kg。在复合污染条件下.两种植物对铅、锌和铅、镉的吸收在不同浓度范围内分别存在存在着协同效应和桔抗效应;同时两种植物对锌、银元素在实验涉及浓度范围内都存在着拮抗效应。这对于深入研究复合污染条件下重金属的土壤环境化学行为,对植物的综合毒性以及不同植物对重金属的吸收累积效应等,具有一定的参考意义。 相似文献
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目的:探讨染料木素对铅诱导的细胞毒性的影响。方法:PC12细胞分为对照组、染铅组、染料木素组以及铅加染料木素组;MTT实验检测细胞活力的改变,流式细胞仪检测细胞凋亡水平的变化,荧光探针检测线粒体形态的改变,Western blot方法检测线粒体融合分裂相关蛋白表达水平的变化。结果:铅可诱导PC12细胞活力的下降以及细胞凋亡率的显著增高,染料木素可抑制铅的这些毒性效应。与此同时,铅可诱导线粒体形态的损伤性改变,线粒体融合减少,分裂增多;而加入染料木素之后,线粒体损伤程度显著下降,线粒体分裂减少,融合增多。此外,线粒体融合相关蛋白Mfn2的水平在铅暴露后显著下降,而线粒体分裂相关蛋白Drp1的水平在铅暴露后显著升高,染料木素干预后均有所恢复。结论:染料木素可抑制铅诱导的PC12细胞毒性,其作用可能与其对线粒体融合分裂过程的干预有关。 相似文献
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目的:探讨染料木素对铅诱导的细胞毒性的影响。方法:PC12细胞分为对照组、染铅组、染料木素组以及铅加染料木素组;MTT实验检测细胞活力的改变,流式细胞仪检测细胞凋亡水平的变化,荧光探针检测线粒体形态的改变,Western blot方法检测线粒体融合分裂相关蛋白表达水平的变化。结果:铅可诱导PC12细胞活力的下降以及细胞凋亡率的显著增高,染料木素可抑制铅的这些毒性效应。与此同时,铅可诱导线粒体形态的损伤性改变,线粒体融合减少,分裂增多;而加入染料木素之后,线粒体损伤程度显著下降,线粒体分裂减少,融合增多。此外,线粒体融合相关蛋白Mfn2的水平在铅暴露后显著下降,而线粒体分裂相关蛋白Drp1的水平在铅暴露后显著升高,染料木素干预后均有所恢复。结论:染料木素可抑制铅诱导的PC12细胞毒性,其作用可能与其对线粒体融合分裂过程的干预有关。 相似文献
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重金属土壤微生物的生态效应 总被引:22,自引:8,他引:14
通过分析重金属对土壤微生物生化过程与数量、种群及群落的影响、影响重金属对土壤微生物毒性的因素、重对土壤微生物毒性的评价指标、微生物对重金属的耐性与适应性以及重金属毒性的差异,综合评述了重金属对土壤微生物生态效应。 相似文献
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海洋微塑料污染的生态效应研究进展 总被引:9,自引:0,他引:9
海洋微塑料污染已成为全球性环境问题。微塑料粒径小,易与海洋生物发生相互作用,可通过多种途径进入海洋生物体内,并在其组织和器官中蓄积和转移,对机体产生毒害。微塑料可沿食物链进行传递,威胁海洋生态系统的健康与稳定。因此,海洋生物与微塑料的相互作用以及海洋微塑料污染的生态效应成为当前研究的热点。综述微塑料的生物附着、生物摄入、对海洋生物的毒性效应及其与化学污染物的复合毒性效应研究的基础上,提出未来微塑料生态效应研究应重点关注我国海洋环境中微塑料的污染现状及生物摄入状况、微塑料的生物效应及其毒理学机制研究、微塑料与其他污染物的复合效应、以及微塑料在海洋生态系统中的作用及其生物地球化学行为等。 相似文献
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Sulfur dioxide (SO2) is a common air pollutant and is detrimental to many organs. Its toxic effects including oxidative damage, deoxyribonucleic acid (DNA) damage and inflammation have been extensively studied. However, recent studies showed that SO2 can be generated endogenously in mammals. In contrast to the toxic effects of SO2, protective effects have also been found in mammals. Endogenous SO2 has antioxidant, anti-inflammatory, anti-hypertension, and anti-atherogenic effects and regulates vascular tone and cardiac function in mammals. SO2 may have a dual role in regulating physiological and pathophysiological effects in mammals. The biological effects of SO2 in mammals are reviewed in this study. 相似文献
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Safety assessment of genetically modified organisms of plant origin in the Russian Federation 总被引:1,自引:0,他引:1
The beginning of the 21st century is characterized by growing interest in the problems of biosafety, which are determined, on the one hand, by the wide use of novel biotechnologies and the necessity to develop the adequate precautionary measures, and, on the other hand, by the objective threat of bioterrorism. Therefore, improvement of the estimation system for genetically modified (GM) sources of food and strengthening the control of their circulation are the urgent problems of modern biology and medicine. Russia is one of the countries where the estimation system of food products obtained from the GM sources is rather efficient. The key features of this system are the complex toxicological and epidemiological examinations. One of the main parts of GM food safety assessment is based upon detection of their potentially toxic properties, which could provoke unintended effects of the genetic modification. 相似文献
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Selection of cryoprotectants based on their toxic effects on oyster gametes and embryos 总被引:1,自引:0,他引:1
Nascimento IA Leite MB Sampaio de Araújo MM Sansone G Pereira SA do Espírito Santo EM 《Cryobiology》2005,51(1):113-117
Cryopreservation is a valuable tool for aquaculture by providing continuous seed production, regardless of the spawning seasons. This study aimed to select the least toxic among the cryoprotectants dimethyl sulfoxide (Me2SO), propylene glycol (PG), and methanol (MET) based on their toxicological effects on Crassostrea rhizophorae gametes and trochophores. They were exposed for 10, 20, and 30 min to a range of concentrations of those cryoprotectants. The endpoint was EC15-24 h (effective concentration which causes abnormalities in 15% of the population exposed to the cryoprotectants for 24 h), recently determined as the chronic value (the concentration at which chronic effects are first observed) for C. rhizophorae embryonic phases. There were no significant differences (p>0.05) among the exposure times in Me2SO toxic effects to either gametes or trochophores. For MET, the increase in exposure time resulted in higher toxicity for gametes, but not for trochophores, while for PG there was a significant (p>0.05) increase in toxicity with the increase of exposure for trochophores and spermatozoa, but not for oocytes. For gametes, MET was the most toxic among the cryoprotectants, while PG was the most toxic for trochophores. 相似文献
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Germinario RJ Colby-Germinario SP 《In vitro cellular & developmental biology. Animal》2003,39(7):275-279
Protease inhibitors in combination with other antiretroviral drugs have been shown to be efficacious in treating human immunodeficiency virus-1 (HIV-1) infection. The side effects of such a treatment usually involve perturbations of fat metabolism and insulin responsiveness. This has led to a number of studies on the adverse effects of these drugs in vitro. The concentrations of various protease inhibitors used in many of these studies were >20 microM. Although some investigators did address the toxicity of protease inhibitors, no overall effort was made to examine this effect during differentiation of fat or muscle. In this study, we assessed the toxicity of HIV-1 protease inhibitors over a range of concentrations (i.e., 0 to 100 microM) in nondifferentiating (e.g., human fibroblasts, 3T3-L1 preadipocytes, and L6 myoblasts) and differentiated cells (e.g., L6 myotubes). The most toxic protease inhibitor in all cell types was Saquinavir (sqv), whereas the least toxic protease inhibitor was Indinavir (idv). Ritonavir (rtv) and Amprenavir (apv) were more toxic than idv but not quite as toxic as sqv. In 3T3-L1 preadipocytes, treatment with sqv, rtv, and apv resulted in toxicity, whereas idv was not toxic even at the highest concentration used. Indinavir was not toxic to L6 myoblasts or L6 myotubes; however, sqv, rtv, and apv caused toxicity in L6 myoblasts. Saquinavir decreased L6 myotube viability in a dose-dependent manner. Human immunodeficiency virus-1 protease inhibitors were shown to be toxic in a variety of cell types. These effects on human fibroblasts and muscle cells have not been reported previously. 相似文献
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W. -Y. Xu-van Opstal C. Billardon T. Caillaud S. Carvajal-Gonzalez G. Colliot J. -C. Bisconte W. Rostene 《Cell biology and toxicology》1994,10(5-6):387-392
An automated system, TRAKCELL, was developed for the quantitation of cells in culture. It enabled cell counting, classification according to morphological cell characteristics and measurement of cell proliferation and differentiation. The system was tested on the toxic effect of ascorbic acid on rat brain catecholaminergic neurons in primary culture. In parallel, the effects of nerve growth factor, dexamethasone and forskolin on cell differentiation were studied using rat pheochromocytoma PC12 cells. The results show that the system permits rapid and reproducible measurements of cell density and of the morphological changes observed following various drug treatments.Abbreviations DEX
dexamethasone
- FSK
forskolin
- NGF
nerve growth factor
- TH
tyrosine hydroxylase 相似文献
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Many toxic substances have been distributed to the environment, some of which have properties that promote accumulation and biomagnification in living organisms. Approximately 1.2 million metric tons of polychlorinated biphenyls (PCBs) have been produced and about 30% have been discharged to the environment. Approximately 200 000 metric tons of brominated flame retardants (BFRs) are produced annually, of which considerable amounts have been spread globally, even to the Polar Regions. Behavioral testing of animals has shown that these compounds may affect learning, memory and fine motor functions. Animals are most sensitive during early development. Several epidemiological studies have shown that PCBs and BFRs may be responsible for similar effects in humans. Of especially concern are possible effects of PCBs and BFRs in mixtures containing the highly neurotoxic methyl mercury. The compounds affect several targets in the nervous system that seem to be interconnected, and may be responsible for the observed behavioral deficits. It was shown early that PCBs affect dopamine and serotonin levels in the brain. Later studies showed that transport mechanisms of these neurotransmitters appear to be particularly sensitive to PCBs. Furthermore, PCBs affect intracellular calcium levels and induce formation of reactive oxygen species both in vivo and in vitro, and reduce cell viability in vitro. Neuroendocrine functions, particularly the thyroid hormone system, are also sensitive to disruption by PCBs and BFRs. Their metabolites, such as hydroxy‐metabolites, appear to be particularly potent. We conclude that PCBs are particularly toxic during early development and that the toxic effects are a combination of several factors, including disturbance of calcium homeostasis, oxidative stress, and influence on neurotransmitter transport. Monoaminergic cells appear to be particularly vulnerable. 相似文献
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Bonner WM 《Mutation research》2004,568(1):33-39
For several decades, the prevailing paradigm for modeling the effects of ionizing radiation (IR) on living systems was the target model with its inherent assumptions--that only those cells in the radiation path whose molecules sustained collisions with high energy particles and rays were damaged, that the damage was proportional to the energy absorbed by each cell and to the number of cells absorbing energy, and that all cells had identical sensitivities to radiation. However, evidence has accumulated that cells exhibit phenomena at low radiation exposures that appear to contradict at least one of these assumptions. Some of these phenomena currently under active study include low-dose hypersensitivity (HRS), increased radiation radioresistance (IRR), the adaptive response (AR), the bystander effect (BE), and death-inducing factor (DIE). These effects may interact to give rise to other phenomena such as hormesis, in which small amounts of otherwise toxic agent appear to be beneficial. Elucidating the cellular and molecular bases for these phenomena will lead to greater understanding of the relationships of these processes, including hormesis, to human health. 相似文献