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91.
Altenhöfer S Kleikers PW Radermacher KA Scheurer P Rob Hermans JJ Schiffers P Ho H Wingler K Schmidt HH 《Cellular and molecular life sciences : CMLS》2012,69(14):2327-2343
Reactive oxygen species (ROS) are cellular signals but also disease triggers; their relative excess (oxidative stress) or shortage (reductive stress) compared to reducing equivalents are potentially deleterious. This may explain why antioxidants fail to combat diseases that correlate with oxidative stress. Instead, targeting of disease-relevant enzymatic ROS sources that leaves physiological ROS signaling unaffected may be more beneficial. NADPH oxidases are the only known enzyme family with the sole function to produce ROS. Of the catalytic NADPH oxidase subunits (NOX), NOX4 is the most widely distributed isoform. We provide here a critical review of the currently available experimental tools to assess the role of NOX and especially NOX4, i.e. knock-out mice, siRNAs, antibodies, and pharmacological inhibitors. We then focus on the characterization of the small molecule NADPH oxidase inhibitor, VAS2870, in vitro and in vivo, its specificity, selectivity, and possible mechanism of action. Finally, we discuss the validation of NOX4 as a potential therapeutic target for indications including stroke, heart failure, and fibrosis. 相似文献
92.
Bis JC DeCarli C Smith AV van der Lijn F Crivello F Fornage M Debette S Shulman JM Schmidt H Srikanth V Schuur M Yu L Choi SH Sigurdsson S Verhaaren BF DeStefano AL Lambert JC Jack CR Struchalin M Stankovich J Ibrahim-Verbaas CA Fleischman D Zijdenbos A den Heijer T Mazoyer B Coker LH Enzinger C Danoy P Amin N Arfanakis K van Buchem MA de Bruijn RF Beiser A Dufouil C Huang J Cavalieri M Thomson R Niessen WJ Chibnik LB Gislason GK Hofman A Pikula A Amouyel P Freeman KB Phan TG Oostra BA Stein JL 《Nature genetics》2012,44(5):545-551
Aging is associated with reductions in hippocampal volume that are accelerated by Alzheimer's disease and vascular risk factors. Our genome-wide association study (GWAS) of dementia-free persons (n = 9,232) identified 46 SNPs at four loci with P values of <4.0 × 10(-7). In two additional samples (n = 2,318), associations were replicated at 12q14 within MSRB3-WIF1 (discovery and replication; rs17178006; P = 5.3 × 10(-11)) and at 12q24 near HRK-FBXW8 (rs7294919; P = 2.9 × 10(-11)). Remaining associations included one SNP at 2q24 within DPP4 (rs6741949; P = 2.9 × 10(-7)) and nine SNPs at 9p33 within ASTN2 (rs7852872; P = 1.0 × 10(-7)); along with the chromosome 12 associations, these loci were also associated with hippocampal volume (P < 0.05) in a third younger, more heterogeneous sample (n = 7,794). The SNP in ASTN2 also showed suggestive association with decline in cognition in a largely independent sample (n = 1,563). These associations implicate genes related to apoptosis (HRK), development (WIF1), oxidative stress (MSR3B), ubiquitination (FBXW8) and neuronal migration (ASTN2), as well as enzymes targeted by new diabetes medications (DPP4), indicating new genetic influences on hippocampal size and possibly the risk of cognitive decline and dementia. 相似文献
93.
Biegel E Schmidt S González JM Müller V 《Cellular and molecular life sciences : CMLS》2011,68(4):613-634
Microbes have a fascinating repertoire of bioenergetic enzymes and a huge variety of electron transport chains to cope with
very different environmental conditions, such as different oxygen concentrations, different electron acceptors, pH and salinity.
However, all these electron transport chains cover the redox span from NADH + H+ as the most negative donor to oxygen/H2O as the most positive acceptor or increments thereof. The redox range more negative than −320 mV has been largely ignored.
Here, we have summarized the recent data that unraveled a novel ion-motive electron transport chain, the Rnf complex, that
energetically couples the cellular ferredoxin to the pyridine nucleotide pool. The energetics of the complex and its biochemistry,
as well as its evolution and cellular function in different microbes, is discussed. 相似文献
94.
95.
超支化不饱和聚(酰胺-酯)的改性及热分解动力学 总被引:3,自引:0,他引:3
采用不同链长的十四酰氯和十八酰氯对超支化不饱和聚(酰胺-酯)(MHBP)的端羟基进行原位端基改性,制备出2种改性超支化聚合物,用傅立叶红外光谱(FTIR)、热重分析(TGA)、黏度法等对其结构及性能进行表征,并研究了它们的热分解行为及其热分解动力学.结果表明,其热分解反应不是一级反应,改性超支化聚合物的热稳定性与末端烷烃链的长度有关,用Ozawa法求出了热分解表观活化能. 相似文献
96.
加筋土技术的理论研究与工程应用 总被引:5,自引:0,他引:5
概述了加筋技术的概念、应用领域、特点和发展。介绍了国内外加筋机理的理论研究和设计方法,以及在工程中大量采用的加筋挡墙、加筋土坡、加筋土垫层的设计方法和应用特点。 相似文献
97.
Spontaneous mutation rate 总被引:2,自引:0,他引:2
98.
Brigitte Ziegler Barbara Wilke M. Ziegler S. Schmidt H. Zühlke 《Cellular and molecular life sciences : CMLS》1980,36(4):467-468
Summary Isolated islets from C57B1/6J mice exposed to 10 mmoles/1 glucose supplemented with 5 g/ml glibenclamide for 48 h released significantly less insulin in the subsequent short-time incubation thanuntreated controls (without glibenclamide), whereas insulin biosynthesis was not suppressed by glibenclamide treatment.Investigations were carried out as a part of the ForschungsprojektDiabetes mellitus und Fettstoffwechselstörungen, supported by the Ministry of Health of the GDR. 相似文献
99.
100.
中频反应磁控溅射制备具有光致亲水性TiO2薄膜 总被引:1,自引:0,他引:1
采用中频反应磁控溅射方法在玻璃表面制备了TiO2薄膜,为使薄膜获得理想的化学配比和较高的沉积速率,使用了等离子体发射光谱监控法(Plasma Emission Monitor,PEM)对溅射过程进行控制。对部分样品进行了退火处理。利用台阶仪测膜厚,X射线衍射(XRD)对薄膜的沉积速率及结构进行测试分析,并对部分沉积态和经过热处理的薄膜样品进行了透光性测试和光照实验。研究了温度,PEM工作点等不同工艺条件对薄膜光致亲水性等性能的影响。部分薄膜经过1h左右的紫外光照射,得到了很好的亲水性效果,其表面的水接触角达到了小于1°的水平。 相似文献