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1.
Acute lung injury (ALI) is a serious disease with unacceptably high mortality and morbidity rates. Up to now, no effective therapeutic strategy for ALI has been established. Rutin, quercetin-3-rhamnosyl glucoside, expresses a wide range of biological activities and pharmacological effects, such as anti-inflammatory, antihypertensive, anticarcinogenic, vasoprotective, and cardioprotective activities. Pretreatment with rutin inhibited not only histopathological changes in lung tissues but also infiltration of polymorphonuclear granulocytes into bronchoalveolar lavage fluid in lipopolysaccharide (LPS)-induced ALI. In addition, LPS-induced inflammatory responses, including increased secretion of proinflammatory cytokines and lipid peroxidation, were inhibited by rutin in a concentration-dependent manner. Furthermore, rutin suppressed phosphorylation of NF-κB and MAPK and degradation of IκB, an NF-κB inhibitor. Decreased activities of antioxidative enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and heme oxygenase-1 caused by LPS were reversed by rutin. At the same time, we found that ALI amelioration by chelation of extracellular metal ions with rutin is more efficacious than with deferoxamine. These results indicate that the protective mechanism of rutin is through inhibition of MAPK–NF-κB activation and upregulation of antioxidative enzymes.  相似文献   
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Hylotelephium spectabile with high tolerance to cadmium (Cd) might be a potential candidate for phytoremediation. However, the mechanisms for Cd accumulation and tolerance in H. spectabile are poorly understood. Four H. spectabile populations, namely HB1, HB2, JS, and LN, were selected to investigate their Cd extraction potential and the underlying mechanism of Cd accumulation, focusing on subcellular distribution and antioxidant enzymes. The Cd concentration, bioconcentration factor and transfer factor of the LN was significantly higher than other populations, particularly with increasing Cd exposure, and no obvious growth inhibition observed. Segregation of excessive Cd to Cd-rich granule in LN was much higher than other populations which reveal one possible mechanism of Cd accumulation. A significant increase in superoxide dismutase (SOD) and catalase (CAT) activities with increasing Cd stress suggested SOD and CAT contribute to the Cd tolerance of H. spectabile. LN displayed significantly higher and constant peroxidase (POD) activities than other populations, which indicated that an effective mechanism existed in the LN to cope with Cd stress. Therefore, the subcellular distribution and antioxidant enzymes might play important roles in Cd accumulation and tolerance of H. spectabile. LN possessed high Cd extraction potential, and further studies under field conditions are warranted.  相似文献   
4.
Cultural attraction theory (CAT) describes a general evolutionary process, cultural attraction, by which the spread and stability of cultural items (beliefs, practices, artifacts, etc.) result not just from differential reproduction, but also from transformations that systematically favor the reconstruction of cultural items of specific types. In this way, CAT aims to provide a general framework for the study of cultural evolution. In a thoughtful critical analysis, Buskell questions the ability of CAT to provide methodological guidance for research in cultural evolution. Can CAT be used to develop the sort of mid‐range theories and models that often drive empirical work? Here we argue that CAT can indeed be used in this way, and we outline the methodological practices that students of cultural attraction have used and are currently developing.  相似文献   
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The enzymes involved in the protection of plant metabolism in presence of azo dye was characterized by studying activities of the role of antioxidant enzymes in the hairy roots (HRs) of Physalis minima L. during degradation of an azo dye, Reactive Black 8 (RB8). When the HRs were exposed to RB8 (30 mg L?1), a nine fold increase in SOD activity was observed after 24 h, while 22 and 50 fold increase in activity was observed for POX and APX respectively after 72 h, whereas there was no significant change in activity of CAT. The activation of different antioxidant enzymes at different time intervals under dye stress suggests the synchronized functioning of antioxidant machinery to protect the HRs from oxidative damage. FTIR analysis confirmed the degradation of dye and the non-toxic nature of metabolites formed after dye degradation was confirmed by phytotoxicity study.  相似文献   
6.
通过测定在不同pH值饲料上桃蚜Myzus persicae(Sulzer)的存活率、繁殖率及其抗氧化酶活性的变化,评价饲料pH值对桃蚜生态和生理指标的影响,筛选扩繁桃蚜饲料最适pH值。结果显示:不同pH值人工饲料饲喂桃蚜,其存活率3d后即呈现显著差异,在试验调查时间内,饲料pH值为7.0处理的存活率、单雌产蚜量和内禀增长率均为最高;不同处理桃蚜体内的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性与对照处理相比均存在显著性差异,在24h左右达到最大值,而后有所下降;饲料pH值为7.0和7.2两处理的酶活性变化幅度较小,在48h后接近正常水平。试验结果表明,扩繁桃蚜较适合的人工饲料pH值为7.0左右。  相似文献   
7.
Catalase is a key enzyme in seed recovery from ageing during priming   总被引:3,自引:0,他引:3  
Ageing induces seed deterioration expressed as the loss of seed vigour and/or viability. Priming treatment, which consists in soaking of seeds in a solution of low water potential, has been shown to reinvigorate aged seeds. We investigate the importance of catalase in oxidation protection during accelerated ageing and repair during subsequent priming treatment of sunflower (Helianthus annuus L.) seeds. Seeds equilibrated to 0.29 g H2O g−1 dry matter (DM) were aged at 35 °C for different durations and then primed by incubation for 7 days at 15 °C in a solution of polyethylene glycol 8000 at −2 MPa. Accelerated ageing affected seed germination and priming treatment reversed partially the ageing effect. The inhibition of catalase by the addition of aminotriazol during priming treatment reduced seed repair indicating that catalase plays a key role in protection and repair systems during ageing. Ageing was associated with H2O2 accumulation as showed by biochemical quantification and CeCl3 staining. Catalase was reduced at the level of gene expression, protein content and affinity. Interestingly, priming induced catalase synthesis by activating expression and translation of the enzyme. Immunocytolocalization of catalase showed that the enzyme co-localized with H2O2 in the cytosol. These results clearly indicate that priming induce the synthesis of catalase which is involved in seed recovery during priming.  相似文献   
8.
麻黄素对仔鼠肾组织结构和SOD、CAT活力及MDA含量的影响   总被引:1,自引:0,他引:1  
为了探讨麻黄素对仔鼠( Mus musculus)肾的毒性影响,对48只仔鼠分别用递增剂量腹腔连续注射麻黄素溶液(2.0、3.0、4.0 g/L)和等量的生理盐水,分别于注射5d、10d和15 d称量仔鼠体重和肾重,用比色法检测肾SOD、CAT活性及MDA含量的变化,用光学显微镜观察仔鼠肾组织结构的变化.结果表明,注射...  相似文献   
9.
Thermal stability of antioxidant defense enzymes superoxide dismutase (SOD, EC 1.15.1.1) and ascorbate peroxidase (APX, EC 1.11.1.11) was studied in chloroplasts and mitochondria of leaf and inflorescence in heat adaptive weed Chenopodium album. Leaf samples were taken in March (31 °C/14 °C) and young inflorescence (INF) was sampled at flowering in April (40 °C/21 °C). Leaf and INF chloroplast and mitochondrial fractions were subjected to elevated temperatures in vitro (5–100 °C) for 30′. SOD and APX showed activity even after boiling treatment in both chloroplast and mitochondria of leaf and INF. SOD was more heat stable than APX in both chloroplasts and mitochondria in both the tissues. Chloroplast contained more heat stable SOD and APX isozymes than mitochondria in both leaf and INF. To the best of our knowledge this is the first report showing presence of thermostable APX isozymes (100 °C for 30′) in chloroplasts and mitochondria in C. album. Heat stable isozymes of SOD and APX in chloroplasts and mitochondria in leaves and inflorescence may contribute to heat tolerance in C. album.  相似文献   
10.
盐胁迫下盐桦生理响应的变化分析   总被引:3,自引:0,他引:3  
对组织培养获得的盐桦(Belula halophila)苗在盐胁迫下的生理指标和解剖结构进行了分析,结果显示,随着盐浓度的增加,植物叶片相对含水量逐渐降低;脯氨酸(Pro)含量逐渐增加;叶片丙二醛(MDA)含量和过氧化氢酶(CAT)活性大小存在相关性,在50~200mmol/L盐胁迫下,植物的CAT活性是递增的,200mmol/LNaCl处理时达到最高,同时叶片MDA含量在50~200mmol/L盐处理时变化不明显;CAT活性在300mmol/LNaCl处理时突然降低,此时叶片MDA含量大;植物叶片和根的离子含量测定表明,在盐胁迫下K^+/Na^+比值逐渐降低,叶片中K^+含量始终高于Na^+含量;石蜡切片和扫描电镜发现盐桦茎、叶中有晶体状物质存在,通过X-ray分析表明这种晶体含有C,O,Ca元素,相关的细胞成分化学实验进一步确定其结晶体的成分。  相似文献   
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