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Silkworm hemolymph contains unique proteins that exhibit anti-apoptotic activity in mammalian cells. Among them, 30 K protein, which is one of the major anti-apoptotic molecules in silkworm hemolymph, has been well investigated. However, little is known about the biological functions of storage protein 1 (SP1), another main protein in silkworm hemolymph. In this study, the anti-apoptotic and anti-oxidative activities of SP1 were analyzed. A stable cell line expressing SP1 was constructed, which showed strong anti-apoptotic effect induced by staurosporine treatment. In addition, the cell line exhibited resistance to oxidative stress caused by hydrogen peroxide. For practical applications of SP1, recombinant SP1 was produced in Escherichia coli, and the supplementation of recombinant SP1 into culture medium exhibited anti-apoptotic and anti-oxidative activities. In addition, SP1 was found to be a cell-penetrating protein and localized in the cytosol as well as on the plasma membrane. The findings showed that SP1 itself is not an anti-oxidant; rather, it mediates intracellular anti-oxidative activity. In conclusion, the cellular resistance of SP1 to apoptosis and oxidative stress will provide a new strategy that could be utilized in the bio-industry for the production of biologics as well as for the development of anti-aging cosmetics.  相似文献   
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TRPM蛋白家族是一类表达于多种哺乳动物细胞中广泛存在的离子通道。近年来发现它们在维持某些特定生理功能中起关 键作用且与人类疾病密切相关。研究显示氧化应激可使TRPM离子通道功能异常导致疾病发生、发展。TRPM亚家族的三个成 员,TRPM2,TRPM4 和TRPM7 均受氧化应激的调控,其功能改变、增加或缺失与炎症及免疫系统的激活、神经退行性疾病和神经 系统疾病、心血管疾病、癌症及糖尿病,代谢紊乱和骨疾病等疾病紧密联系。本文就近年来氧化应激调控的TRPM离子通道与人 类疾病的关系做简要综述。此外,文章也将探讨它们作为药物设计靶点和工具的应用前景。  相似文献   
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目的:探讨左卡尼汀联合蔗糖铁对血透患者肾性贫血及氧化应激的影响。方法:抽选我院2010年3月-2013年5月行维持血透治疗的肾性贫血患者79例,采用数字表法分为对照组(39例)和观察组(40例),对照组采用促红细胞生成素(EPO)、单用蔗糖铁及常规对症治疗,观察组在对照组基础上联用左卡尼汀治疗。比较两组患者治疗前、治疗6个月后血红蛋白(Hb)、血细胞比容(Hct)、血浆铁蛋白(SF)、转铁蛋白饱和度(TSAT)、晚期蛋白质氧化产物(AOPP)及血丙二醛(MDA)水平,并对两组治疗开始时、治疗3、6个月时EPO使用剂量进行比较。结果:治疗6个月后,观察组患者Hb、Hct、SF、TSAT明显高于对照组(P0.05),AOPP、MDA明显低于对照组(P0.05);对照组从治疗开始到治疗6个月时一直维持较高的EPO使用剂量,而观察组EPO用量依次递减,至治疗6个月时EPO用量显著低于对照组(P0.05)。结论:左卡尼汀能联合蔗糖铁治疗肾性贫血的疗效显著,能有效缓解氧化应激反应,降低EPO用量,值得临床推广。  相似文献   
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The usefulness of benthic multi-metric indices when assessing seafloor integrity across broad environmental gradients should be deliberated, as their lack of transparency might hide important sources of variation and fail to identify environmental change. This study compares the performance of two multi-metric indices; the Benthic Quality Index (BQI) and the Brackish water Benthic Index (BBI) between three sub-basins in the Baltic Sea. Both indices reflect the salinity-driven gradient in macroinvertebrate diversity and composition as well as changes in bottom water oxygen concentrations. The relative contribution of predictor variables for explaining index variation does, however, differ between sub-basins, resulting in the indices representing different aspects of the benthic community along the environmental gradient. This context-dependency is caused by inherent differences in benthic community characteristics between the sub-basins of the Baltic Sea, and how the communities are portrayed by the indices. An increased transparency of the importance of the different predictors for directing index values is needed for coherent classifications over broad environmental gradients, such as those occurring in large estuarine water bodies. Use of a weight of evidence table to combine multiple indicators would preserve transparency and be more likely to provide a robust assessment method that would detect seafloor degradation at an early stage.  相似文献   
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Facilitation is an important driver of community assembly, and often overwhelms the effect of competition in stressed habitats. Thus, net effect of biotic interactions is often positive in stressed grasslands, where dominant species and litter can protect the subordinate species. Besides facilitation, niche partitioning can also support species coexistence leading to limiting similarity between subordinate species. Our aim was to provide a detailed analysis of fine-scale biotic interactions in stressed alkali grasslands. We supposed, that there are positive relationships between the main biomass fractions and species richness. We expected the expansion of trait ranges and the increase of trait dissimilarity with increasing biomass scores (total litter, green biomass of dominant species) and species richness. We studied the relationships between main biomass fractions, species richness, functional diversity and functional trait indices (ranges, weighted means and Rao indices). We used fine-scale biomass sampling in nine stands of dry alkali grasslands dominated by Festuca pseudovina. The detected relationships were always positive between the main biomass fractions (green biomass of dominant species, total litter and green biomass of subordinate species) and species richness. We found that the green biomass of dominant species and total litter increased ranges and dissimilarity of functional traits. Our results suggest that in dry alkali grasslands facilitation is crucial in shaping vegetation composition. The green biomass of dominant species and total litter increased the biomass production of subordinate species leading to overyielding. We found that mechanisms of facilitation and limiting similarity were jointly shaping the species coexistence in stressed grasslands, such as alkali grasslands.  相似文献   
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Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson’s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population.  相似文献   
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