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101.
柠檬醛损伤黄曲霉线粒体生化机理的研究 总被引:18,自引:2,他引:18
应用生物化学方法并结合扫描电镜,研究柠檬醛掺入黄曲霉细胞,并通过损伤线粒体(Mt),导致抑制其生长的机理。结果表明,在药物致敏浓度时,菌丝体经该醛作用后,胞内Mt呈不规则增多,氧化还原反应系统受到破坏,与对照组相比,柠檬醛组的琥珀酸脱氢酶(Succinate Dehydrogenase,SDH)、苹果酸脱氢酶(Malate Dehydrogenase,MDH)活性分别呈不可逆下降271%和242%,随着药物浓度的升高,SDH、MDH的活性直至消失;以琥珀酸、α酮戊二酸和丙酮酸为底物时,线粒体呼吸速率分别下降24.1%、14.3%和36.1%,提示柠檬醛能使菌丝体DNA、RNA、脂类和蛋白质等生物合成受到抑制,促进细胞死亡。 相似文献
102.
Anla Hu Li Li Chuanlai Hu Daoming Zhang Chen Wang Yan Jiang Meng Zhang Chunmei Liang Wenjun Chen Qingli Bo Qihong Zhao 《Biological trace element research》2018,182(1):21-28
Data on the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress among women with polycystic ovary syndrome (PCOS) are scarce. The objective of this study was to assess the effects of magnesium-zinc-calcium-vitamin D co-supplementation on hormonal profiles, biomarkers of inflammation, and oxidative stress in women with PCOS. Sixty PCOS women were randomized into two groups and treated with 100 mg magnesium, 4 mg zinc, 400 mg calcium plus 200 IU vitamin D supplements (n = 30), or placebo (n = 30) twice a day for 12 weeks. Hormonal profiles, biomarkers of inflammation, and oxidative stress were assessed at baseline and at end-of-treatment. After the 12-week intervention, compared with the placebo, magnesium-zinc-calcium-vitamin D co-supplementation resulted in significant reductions in hirsutism (?2.4 ± 1.2 vs. ?0.1 ± 0.4, P < 0.001), serum high sensitivity C-reactive protein (?0.7 ± 0.8 vs. +0.2 ± 1.8 mg/L, P < 0.001), and plasma malondialdehyde (?0.4 ± 0.3 vs. +0.2 ± 1.0 μmol/L, P = 0.01), and a significant increase in plasma total antioxidant capacity concentrations (+46.6 ± 66.5 vs. ?7.7 ± 130.1 mmol/L, P = 0.04). We failed to find any significant effect of magnesium-zinc-calcium-vitamin D co-supplementation on free androgen index, and other biomarkers of inflammation and oxidative stress. Overall, magnesium-zinc-calcium-vitamin D co-supplementation for 12 weeks among PCOS women had beneficial effects on hormonal profiles, biomarkers of inflammation, and oxidative stress. 相似文献
103.
104.
K Y Jiang O Pitiot M Anissimova H Adenier M A Vijayalakshmi 《Biochimica et biophysica acta》1999,1433(1-2):198-209
Chemical glycosylation of bovine alpha-chymotrypsin, by a glucosamine adduct on the carboxyl group, results in the modification of its catalytic activity. The structural alterations of alpha-chymotrypsin resulting from its glycosylation are studied by immobilized metal-ion affinity chromatography (IMAC) and immobilized metal-ion affinity capillary electrophoresis (IMACE). The chemical glycosylation of alpha-chymotrypsin generates two distinct subpopulations of the protein: one which totally loses the initial affinity for IDA-Cu(II) and another which exhibits an increased affinity for the metal chelate ligand. 相似文献
105.
Zhenwei Qiu Yongbing Zhang Dorothea Bedigian Xiao Li Changsui Wang Hongen Jiang 《Economic botany》2012,66(3):255-263
Sesame Utilization in China: New Archaeobotanical Evidence from Xinjiang. A cache of sesame (Sesamum indicum L.) seeds, discovered in the Thousand Buddha Grottoes at Boziklik, Turpan, China, dating to ca. 700 years before present (BP), is hard evidence of their use in China since that time. Morphological and anatomical features suggest a white sesame cultivar. The sizeable quantity unearthed implies that sesame was a valued commodity that could provision the monks and enrich the diet of ancient inhabitants as an oil source. 相似文献
106.
107.
William K. K. Wu Minyi He Liang Zhao Xuegang Sun Hui Li Yong Jiang Yungao Yang Kang Peng 《Cell biochemistry and function》2012,30(4):271-278
Triptolide is a diterpenoid triepoxide derived from the traditional Chinese medical herb Tripterygium wilfordii. In the present study, we demonstrated that this phytochemical attenuated colon cancer growth in vitro and in vivo. Using a proteomic approach, we found that 14‐3‐3 epsilon, a cell cycle‐ and apoptosis‐related protein, was altered in colon cancer cells treated with triptolide. In this regard, triptolide induced cleavage and perinuclear translocation of 14‐3‐3 epsilon. Taken together, our findings suggest that triptolide may merit investigation as a potential therapeutic agent for colon cancer, and its anticancer action may be associated with alteration of 14‐3‐3 epsilon. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
108.
109.
Ying?Wu Rui?Wu Bangjiao?Zhang Tingting?Jiang Ning?Li Kai?Qian Bao?LiuEmail author Jian?ZhangEmail author 《Plant Growth Regulation》2012,66(2):137-143
Gardenia jasminoides Ellis is an evergreen tropical plant and favorite to gardeners throughout the world. Several studies have documented that
in vitro micropropagation can be used for clonal propagation of G. jasminoides Ellis, the efficiency remained low. In addition, no information is available on the genetic and epigenetic fidelity of the
micropropagated plants. Here, we report on a simplified protocol for high efficient micropropagation of G. jasminoides Ellis cv. “Kinberly” based on enhanced branching of shoot-tips as explants. The protocol consisted of sequential use of three
media, namely, bud-induction, elongation and root-induction. By using two molecular markers, amplified fragment length polymorphism
(AFLP) and methylation sensitive amplified polymorphism (MSAP), we analyzed the genetic and DNA methylation pattern stability
of 23 morphologically normal plants randomly taken from a sub-population (>100) of micropropagated plants originated from
a single shoot-tip. We found that of >1,000 scored AFLP bands across the 23 micropropagated plants, no incident of genetic
variation was detected. In contrast, of 750 scored MSAP bands, moderate but clear alteration in several DNA methylation patterns
occurred in the majority of the 23 micropropagated plants. The changed methylation patterns involved both CG and CHG sites
representing either hyper- or hypo-methylation, which occurred without altering the total methylation levels partly due to
concomitant hyper- and hypo-methylation alterations. Our results indicated that epigenetic instability in the form of DNA
methylation patterns can be susceptible to the in vitro micropropagation process for G. jasminoides Ellis, and needs to be taken into account in the process of large-scale commercial propagation of this plant. 相似文献
110.