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11.
In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells. 相似文献
12.
目的:观察地尔硫对冠心病病人的抗脂质过氧化及抗氧自由基作用。方法:冠心病病人30例为治疗组(男性21例,女性9例,年龄58±s6a),给予地尔硫30mg,po,tid,共4wk。健康人组30例(男性18例,女性12例,年龄58±9a)。结果:治疗组在给药前较健康人组的血清oxLDL,LPO,SCL,LCL值显著升高,P<0.01,GSH-Px显著降低,P<0.01,SOD活力两者无明显差异,P>0.05。治疗组用药后与用药前相比oxLDL,LPO,SCL,LCL值显著下降,P<0.01或<0.05,GSH-Px显著升高,P<0.01,治疗组治疗后与健康人组相比,除LCL外,其他指标皆无明显差异,P>0.05。结论:地尔硫是一良好的抗氧化剂。 相似文献
13.
Kaneo Yoshiharu Fujihara Yumie Tanaka Tetsuro Kozawa Yoko Mori Hideki Iguchi Sadao 《Pharmaceutical research》1989,6(12):1025-1031
Glutathione was covalently attached to dextran (T-40) by the CNBr activation method. The compound obtained was a water-soluble powder containing 10 (w/w%) glutathione, which was gradually released from the conjugate in aqueous media. Mice depleted of glutathione by treatment with buthionine sulfoximine, a potent inhibitor of -glutamylcysteine synthetase, exhibited a significant increase in hepatic glutathione level after intravenous injection of the conjugate. In mice given a lethal dose of acetaminophen, the survival rate increased progressively with coadministration of the conjugate, whereas little improvement was found when free glutathione was given. The conjugate maintained the serum transaminase activities at lower level after acetaminophen administration. These findings suggest that the dextran conjugate of glutathione is transported into hepatic cells and is intracellulary hydrolyzed to free form, which protects mice from hepatotoxicity due to acetaminophen. 相似文献
14.
15.
Liu CS Chen HW Lii CK Tsai CS Kuo CL Wei YH 《Environmental and molecular mutagenesis》2002,40(3):168-174
The effects of long-term smoking on mitochondrial DNA (mtDNA) deletions in hair follicles were investigated in subjects with different antioxidant capacity. Twenty-two male smokers with a smoking index of greater than 5 pack-years and without any known systemic diseases were recruited for this study. Forty healthy nonsmoking males were included as controls. We found that the concentrations of ascorbate and alpha-tocopherol and the activities of glutathione S-transferase (GST) and glutathione peroxidase in blood plasma were significantly decreased in smokers. The levels of glutathione and protein thiols in whole blood and the incidence of a 4,977 bp deletion of mtDNA (dmtDNA) in hair follicles were significantly increased in smokers. A significantly higher incidence of the 4,977 bp dmtDNA was found in smokers with plasma GST activity less than 5.66 U/l (OR = 7.2, P = 0.020). Using multiple covariate ANOVA and logistic regression, we found that age and low plasma GST activity were the only two risk factors for the 4,977 bp dmtDNA. These results suggest that smoking depletes antioxidants and causes mtDNA deletions and that plasma GST may play an important role in the preservation of the mitochondrial genome in tissue cells of smokers. 相似文献
16.
F. V. Donenko S. M. Sitdikova A. O. Kabieva B. E. Polotskii Z. O. Machaladze M. I. Davydov L. V. Moroz 《Bulletin of experimental biology and medicine》1995,119(2):206-208
Preincubation of cells of BDF1 hybrid mice with P388 leukemia with doxorubicin and buthionine sulfoximine leads to the manifestation
of a therapeutic effect of the antibiotic. Injection of buthionine sulfoximine and ethacrinic acid to mice with leukemia does
not alter the therapeutic effect of the antibiotic.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N
o
2, pp. 212–214, February, 1995
Presented by N. N. Trapeznikov, Member of the Russian Academy of Medical Sciences 相似文献
17.
P糖蛋白和谷胱甘肽—S—转移酶在肾细胞癌中的表达 总被引:2,自引:1,他引:2
探讨肾细胞癌与多药耐药的关系,方法:应用免疫组化方法,检测4例术前未进行化疗的肾细胞癌和16例正常肾组织中的P糖蛋白和谷胱甘肽-2转移-π表达。结果:P-ag和GST-π外地16例正常肾组织中的表达率均匀100%,在44例肾细胞癌组织中分别为63.65和54.5%Pg,P-gp和/或GST-π阳性表达率为79.5%。 相似文献
18.
Physical training and fasting erythrocyte activities of free radical scavenging enzyme systems in sedentary men 总被引:3,自引:0,他引:3
H. Ohno T. Yahata Y. Sato K. Yamamura N. Taniguchi 《European journal of applied physiology》1988,57(2):173-176
Summary Effects of 10 weeks of physical training on free radical scavenging enzyme systems in erythrocytes were investigated in 7 sedentary healthy male students. The training consisted of running over 5 km, 6 times/week. Their maximum oxygen uptake and 12 min walk-run performance increased significantly after training. Of the antioxidant enzyme systems examined in the erythrocytes, both catalase activity and concentration and total glutathione reductase (GR) activity also showed significant increases following the training. The erythrocyte GR activity coefficient also increased significantly. These results suggest that chronic aerobic exercise increases riboflavin requirements and has some positive effects on antioxidative processes. 相似文献
19.
20.
P. V. Sergeev S. A. Chukaev Yu. A. Korovkina 《Bulletin of experimental biology and medicine》1997,124(2):786-788
Effects of estradiol and testosterone and of the antiandrogens cyproterone acetate, niftolide, and antiestrogen tamoxifen
on the activities of human erythrocyte glutathione peroxidase and glutathione reductase were studiedin vitro. In contrast to hormone preperations, antihormones in high concentrations (10−4−5×10−4 M) modified the enzyme activities. Cyproterone acetate and tamoxifen increased the activity of glutathione reductase, while
tamoxifen stimulated glutathione reductase and inhibited glutathione peroxidase. Niftolide inhibited both enzymes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 185–187, August, 1997 相似文献