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81.
Time‐lapse microscopy of oxidative stress demonstrates metabolic sensitivity of retinal pericytes under high glucose condition 下载免费PDF全文
Hyperglycemia affects retinal vascular cell function, promotes the development and progression of diabetic retinopathy and ultimately causes vision loss. Oxidative stress, reactive oxygen species (ROS) in excess, is a key biomarker for diabetic retinopathy. Using time‐lapse fluorescence microscopy, ROS dynamics was monitored and the metabolic resistivity of retinal endothelial cells (REC) and pericytes (RPC) was compared under metabolic stress conditions including high glucose (HG). In the presence of a mitochondrial stressor, REC exhibited a significant increase in the rate of ROS production compared with RPC. Thus, under normal glucose (NG), REC may utilize oxidative metabolism as the bioenergetic source, while RPC metabolic activity is independent of mitochondrial respiration. In HG condition, the rate of ROS production in RPC was significantly higher, whereas this rate remained unchanged in REC. Thus, under HG condition RPC may preferentially utilize oxidative metabolism, which results in increased rate of ROS production. In contrast, REC use glycolysis as their major bioenergetic source for ATP production, and consequently HG minimally affects their ROS levels. These observations are consistent with our previous studies where we showed HG condition has minimal effect on apoptosis of REC, but results in increased rate of apoptosis in RPC. Collectively, our results suggest that REC and RPC exhibit different metabolic activity preferences under different glucose conditions. Thus, protection of RPC from oxidative stress may provide an early point of intervention in development and progression of diabetic retinopathy. 相似文献
82.
好氧反硝化微生物学机理与应用研究进展 总被引:3,自引:0,他引:3
近年来,关于好氧反硝化过程的研究主要集中在三个方面:分别是好氧反硝化菌株的分离和脱氮性能表征,好氧反硝化微生物的应用潜力分析,以及好氧反硝化过程的机理研究。好氧反硝化菌株分布范围广泛,可从多种环境中分离得到,种属以Pseudomonas sp.、Alcaligenes sp.和Paracoccus sp.为主。好氧反硝化菌株及菌群在实验室条件下表现出优良的耐冷、耐盐特性,并具有可降解毒性有机物及N_2O减排的潜力。关于好氧反硝化过程的机理研究表明,虽然硝酸盐作为电子受体的竞争力比氧气弱,但反硝化作为辅助电子传递途径,可提高产能效率,防止NAD(P)H的过量积累。因此,硝酸盐可与氧气同时参与微生物的新陈代谢,即发生好氧反硝化现象。未来除了继续分离更新更好的好氧反硝化菌株外,应加强对好氧反硝化机理及实际生物强化方面的研究。 相似文献
83.
84.
Rita D.G. Franca Helena M. Pinheiro Mark C.M. van Loosdrecht Nídia D. Lourenço 《Biotechnology advances》2018,36(1):228-246
Aerobic granular sludge technology has been extensively studied over the past 20 years and is regarded as the upcoming new standard for biological treatment of domestic and industrial wastewaters. Aerobic granules (AG) are dense, compact, self-immobilized microbial aggregates that allow better sludge-water separation and thereby higher biomass concentrations in the bioreactor than conventional activated sludge aggregates. This brings potential practical advantages in terms of investment cost, energy consumption and footprint. Yet, despite the relevant advances regarding the process of AG formation, instability of AG during long-term operation is still seen as a major barrier for a broad practical application of this technology. This paper presents an up-to-date review of the literature focusing on AG stability, aiming to contribute to the identification of key factors for promoting long-term stability of AG and to a better understanding of the underlying mechanisms. Operational conditions leading to AG disintegration are described, including high organic loads, particulate substrates in the influent, toxic feed components, aerobic feeding and too short famine periods. These operational and influent wastewater composition conditions were shown to influence the micro-environment of AG, consequently affecting their stability. Granule stability is generally favored by the presence of a dense core, with microbial growth throughout the AG depth being a crucial intrinsic factor determining its structural integrity. Accordingly, possible practical solutions to improve granule long-term stability are described, namely through the promotion of minimal substrate concentration gradients and control of microbial growth rates within AG, including anaerobic, plug-flow feeding and specific sludge removal strategies. 相似文献
85.
Suppression of oxidative phosphorylation confers resistance against bevacizumab in experimental glioma 下载免费PDF全文
Jule A. Eriksson Christina Wanka Michael C. Burger Hans Urban Ines Hartel Janusz von Renesse Patrick N. Harter Michel Mittelbronn Joachim P. Steinbach Johannes Rieger 《Journal of neurochemistry》2018,144(4):421-430
86.
Raju Pusapati 《Cell cycle (Georgetown, Tex.)》2016,15(18):2387-2388
87.
Katarzyna Paradowska Beata Polak Adam Chomicki Grażyna Ginalska 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1712-1717
A bioautographic assay based on thin layer chromatography was developed for phosphoenolpyruvate (PEP) detecting as a known but rarely studied inhibitor of phosphoglucose isomerase (PGI). The protocol with NADP+/NBT/PMS (β-nicotinamide adenine dinucleotide phosphate/nitrotetrazolium blue chloride/phenazine methosulfate) staining was capable of detecting Mycobacterium tuberculosis H37Ra PGI inhibition using PEP. According to this method, visibly brighter spots (zones) against purple background are observed in the area of inhibition of the above-mentioned enzyme activity. The detection limit for PEP as an inhibitor of Mycobacterium tuberculosis H37Ra PGI was 226?μg per spot/zone. Noteworthy is that we are the first authors to have successfully used a bioautographic assay to detect Mycobacterium tuberculosis H37Ra PGI inhibition by PEP. 相似文献
88.
目的:探讨有氧康复运动联合中药口服对脑瘫患儿血清NSE、EF-1、1,25-二羟维生素D3水平变化的影响及临床意义。方法:选取我院收治的脑瘫患儿80例,根据治疗方案不同分为对照组及实验组,对照组予以常规内科治疗及康复锻炼,实验组予以有氧康复联合中药口服治疗。比较各组患儿治疗前后糖化分解烯醇酶NSE、内皮素EF-1、1,25-二羟维生素D3、食欲、排便、面色、体质、淀粉酶等水平变换情况。结果:实验组NSE及EF-1水平低于对照组(P0.05),实验组1,25-二羟维生素D3及微量元素、淀粉酶、体质体征水平高于对照组,其结果均有统计学意义(P0.05)。结论:有氧康复运动联合健脾益气的中药汤药口服可降低脑瘫患儿血清NSE及EF-1间接促进神经系统恢复,且加速1.25-二羟Vit D3合成效率,促进患儿对营养物质的吸收及代谢,治疗小儿脑瘫临床疗效理想。 相似文献
89.
- 1.
- The study evaluated the effects of exposure to cold air (10 °C) on thermal responses, muscle performance and dexterity of muscular subjects and their matched lean counterparts. 相似文献
90.
Isolation and characterization of thermotolerant bacterium utilizing ammonium and nitrate ions under aerobic conditions 总被引:1,自引:0,他引:1
Takenaka S Zhou Q Kuntiya A Seesuriyachan P Murakami S Aoki K 《Biotechnology letters》2007,29(3):385-390
A thermotolerant bacterium, identified as Bacillus licheniformis, completely utilized 0.1% (w/v) NH4NO3 at 30 and 50°C under aerobic condition. The addition of 0.5 mM Fe2+ to the NH4NO3 medium markedly promoted the utilization of NH4+ and NO3−. At 50°C, of total nitrogen originally provided, 24% was taken up into the cells and 20% remained in the culture supernatant.
Residual nitrogen (56%) was probably removed into the atmosphere. The cell extracts contained enzymes involved in denitrification.
GC-MS demonstrated that NH4 15NO3 had been converted to 15N2O. These results indicate that the strain has denitrification ability under aerobic condition. 相似文献