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镉锌交互作用对玉米幼苗生理生化特性的影响 总被引：6，自引：0，他引：6
以不同浓度的镉(Cd2 )、锌(Zn2 )处理玉米，研究CA、Zn单一及复合污染对幼苗生长及生理生化特性的影响．结果表明，随着Cd2 、Zn2 浓度的增加，CA、Zn单一及复合处理的根长，株高、根和地上部干重减少；根内丙二醛(MDA)积累增加，根系活力和叶片硝酸还原酶活性下降，叶绿素含量降低，Cd、Zn交互作用显示出协同作用的趋势。 相似文献
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耐力运动对非酒精性脂肪肝小鼠肝脏NO 水平、NOS 活性及表达的影响 总被引：1，自引：0，他引：1
目的:研究耐力运动对非酒精性脂肪肝小鼠肝脏NO水平、NOS活性及表达的影响。研究方法:雄性8周龄ApoE基因敲除小鼠24只,西方膳食14周后,随机分为2组,非酒精性脂肪肝模型组(H,n=12,14周),跑台运动组(E,n=12,14 12周)。跑台运动12周,坡度为0°,跑速13m/min,60min/time,每周5次。在造模与训练结束后,测定肝脏总NOS、cNOS、iNOS酶活性、NO水平及eNOS和iNOSmRNA的表达,光镜观察脂肪肝病变程度。结果:E组肝脏总NOS、iNOS酶活性和NO水平显著高于H组,cNOS未见显著性改变;E组eNOS和iNOSmRNA表达显著高于H组;E组肝脏实质细胞脂肪滴明显减少。结论:耐力训练在显著降低非酒精性脂肪肝肝脏脂肪滴的同时,伴随着肝脏NO含量、总NOS活性和iNOS活性的显著增加以及eNOS和iNOSmRNA的表达上调,提示运动导致NO、NOS活性和表达的升高在非酒精性脂肪肝发病过程中可能具有重要的生理意义。 相似文献
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Wang LR Zhang GB Chen J Li J Li MW Xu N Wang Y Shen Tu JZ 《Journal of Zhejiang University. Science. B》2011,12(3):174-179
Objective
To evaluate the predictive values of gene expressions of ribonucleotide reductase M1 (RRM1) and breast cancer susceptibility gene 1 (BRCA1) in peripheral blood from Chinese patients with non-small-cell lung cancer (NSCLC) treated with gemcitabine plus platinum. 相似文献5.
四川边茶提取物对脂肪酸合酶的抑制作用 总被引：2，自引：0，他引：2
四川边茶（康砖）是黑茶的一个主要品种，所含茶多酚与绿茶和红茶不同。本研究利用酶动力学方法测定了边茶萃取物对脂肪酸合酶（Fatty Acid Synthase, FAS, E.C. 2.3.1.85）的抑制作用，近几年研究报道该酶是减肥和抑癌的双重潜在靶点。结果表明，边茶萃取物对FAS有可逆和不可逆抑制双重作用，最佳萃取溶剂为50％的乙醇，在常温下5 h即可达到最佳萃取效果。用开水泡茶的方法经两次浸取可提取出近60％的抑制FAS有效物，比绿茶的浸出效率约高1倍，但需较长的浸泡时间。边茶的新茶对脂肪酸合酶的抑制能力并不强，存放数年的边茶抑制能力最好，其后有所下降，但大部分抑制活性可保持20年以上，而30年以上保存期可能会使抑制能力明显下降。边茶提取物与底物乙酰辅酶A和丙二酸单酰辅酶A的竞争性质都是竞争性与非竞争性的混合型；对FAS中的酮酰还原反应的抑制不明显，这说明酮酰还原酶结构域并不是其主要作用位点；这些和绿茶及红茶都有不同。由实验结果分析边茶中的抑制剂不同于红茶和绿茶，可能是茶多酚中的茶褐素，其抑制能力高于儿茶素而接近茶黄素。这些结果表明边茶在减肥、抑癌等方面可能具有良好的应用前景。 相似文献
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Munzir M. E. Ahmed J. A. S. Al-Obosi H. M. Osman M. E. Shayoub 《Indian journal of clinical biochemistry : IJCB》2016,31(2):162-170
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH. 相似文献
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Nitric oxide (NO) a free radical having both cytoprotective as well as tumor promoting agent is formed from l-arginine by converting it to l-citrulline via nitric oxide synthase enzymes. The reaction product of nitric oxide with superoxide generates potent oxidizing
agent, peroxynitrite which is the main mediator of tissue and cellular injury. Peroxynitrite is reactive towards many biomolecules
which includes amino acids, nucleic acid bases; metal containing compounds, etc. NO metabolites may play a key role in mediating
many of the genotoxic/carcinogenic effects as DNA damage, protein or lipid modification, etc. The basic reactions of nitric
oxide can be divided as direct effect of the radical where it alone plays a role in either damaging or protecting the cell
milieu and an indirect effect in which the byproducts of nitric oxide formed by convergence of two independent radical generating
pathways play the role in biological reactions which mainly involve oxidative and nitrosative stress. Nitric oxide is also
capable of directly interacting with mitochondria through inhibition of respiration or by permeability transition. Reaction
of nitric oxide with metal ions include its direct interaction with the metals or with oxo complexes thereby reducing them
to lower valent state. Excessive production of nitric oxide can be studied by inhibiting the synthetic pathway of nitric oxide
using both selective or specific nitric oxide synthase inhibitor or non-selective nitric oxide synthase inhibitor with respect
to isoforms of nitric oxide. 相似文献
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Upendra Yadav Pradeep Kumar Vandana Rai 《Indian journal of clinical biochemistry : IJCB》2021,36(1):23
Methionine synthase reductase (MTRR) is an important enzyme of the folate/homocysteine pathway. It is responsible for regulation of methionine enzyme by reductive methylation. A common variant A66G is reported in the FMN-binding domain of the MTRR gene, which leads to substitution of isoleucine by methionine (I22M) in MTRR enzyme with reduced activity. Reduced catalytic activity of enzyme leads to high homocysteine concentration in blood and increases risk for numerous diseases. The frequency of A66G polymorphism varies in different ethnic groups. The present study has been designed to evaluate the frequency of MTRR A66G gene polymorphism in the Eastern UP population by PCR–RFLP method. Along with this we also performed a meta-analysis to evaluate the global prevalence of this polymorphism. Databases were screened to identified the eligible studies. The prevalence of the G allele and GG genotype was determined by the use of prevalence proportion with 95% CI. Open meta-analyst software was used for the meta-analysis. Total 1000 blood samples were analyzed, the frequencies of A and G alleles were 0.35 and 0.65 respectively. Meta-analysis results revealed that the prevalence of G allele and GG genotype were 49.4% (95% CI 40.6–58.1, p ≤ 0.001) and 24.3% (95% CI 17.8–30.9, p ≤ 0.001) respectively. In sub-group meta-analysis, the lowest frequency of G allele was found in South America (32.7%; 95% CI 14.1–51.3, p ≤ 0.001), and highest in Asia (56.4%; 95% CI 39.5–73.3, p ≤ 0.001). The results of the meta-analysis showed that the Asian population has the highest frequency of G allele and highest frequency of the GG genotype was found in the European population. 相似文献
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常压模拟高住低练和低住高练对大鼠肝脏谷胱甘肽抗氧化系统影响的比较 总被引：6，自引：0，他引：6
目的:探讨常压模拟高住低练和低住高练两种低氧训练方法对SD大鼠肝脏谷胱甘肽抗氧化系统的影响。方法:将成年雄性SD大鼠40只随机分为平原安静组(A)、平原运动组(B)、常压低住高练组(C)和常压高住低练组(D),每组10只,4周后测定大鼠肝脏谷胱甘肽抗氧化系统及相关指标。结果:低住高练组和高住低练组大鼠肝脏GSH、GSH-PX、T-AOC最高,MDA含量最低,两组低氧训练组间没有显著性差异,但与其它组相比较,差异显著(P<0.05)。结论:低住高练和高住低练此两种训练方法均能提高机体谷胱甘肽抗氧化系统能力。 相似文献
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