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111.
Agnes?Lincy?Arokiyanathan Senthilkumar?LakshmipathiEmail authorView authors OrcID profile 《Journal of molecular modeling》2017,23(12):345
A computational study of metal difluorides (MF2; M = Ca to Zn) and their interactions with carbon dioxide and water molecules was performed. The structural parameter values obtained and the results of AIM analysis and energy decomposition analysis indicated that the Ca–F bond is weaker and less ionic than the bonds in the transition metal difluorides. A deformation density plot revealed the stablizing influence of the Jahn–Teller effect in nonlinear MF2 molecules (e.g., where M= Sc, Ti, Cr). An anaysis of the metal K-edge peaks of the difluorides showed that shifts in the edge energy were due to the combined effects of the ionicity, effective nuclear charge, and the spin state of the metal. The interactions of CO2 with ScF2 (Scc3 geometry) and TiF2 (Tic2 geometry) caused CO2 to shift from its usual linear geometry to a bent geometry (η2(C=O) binding mode), while it retained its linear geometry (η1(O) binding mode) when it interacted with the other metal difluorides. Energy decomposition analysis showed that, among the various geometries considered, the Scc3 and Tic2 geometries possessed the highest interaction energies and orbital interaction energies. Heavier transition metal difluorides showed stronger affinities for H2O, whereas the lighter transition metal (Sc and Ti) difluorides preferred CO2. Overall, the results of this study suggest that fluorides of lighter transition metals with partially filled d orbitals (e.g., Sc and Ti) could be used for CO2 capture under moist conditions. 相似文献
112.
Indole butyric acid (IBA) initiates roots in the hypocotyl tissue of Phaseolus vulgaris (French bean). The response is dependent on the concentration of IBA and the duration of exposure to the hormone. IBA enhances the rate of total protein synthesis in ca 30 min after exposure of the hypocotyl segments to the hormone. There is no detectable change in total or poly(A)-containing RNA synthesis in this period although significant increases are seen 2 hr after hormone pre-treatment. The early IBA-mediated increase in protein synthesis (30 min) is not sensitive to Actinomycin D but the antibiotic blocks the increase manifested 2 hr after hormone pre-treatment. Inhibition of early protein synthesis by cycloheximide depresses and delays root initiation. Cytosol prepared from IBA-treated hypocotyl tissue stimulates protein synthesis in vitro to a greater extent than that of the control. 相似文献
113.
114.
V J Dwarki V N Francis G J Bhat G Padmanaban 《The Journal of biological chemistry》1987,262(35):16958-16962
115.
Erin?E.?Congdon Yan?Lin Hameetha?B.?Rajamohamedsait Dov?B.?Shamir Senthilkumar?Krishnaswamy Wajitha?J.?Rajamohamedsait Suhail?Rasool Veronica?Gonzalez Josien?Levenga Jiaping?Gu Charles?Hoeffer Einar?M.?SigurdssonEmail author 《Molecular neurodegeneration》2016,11(1):62
Background
A few tau immunotherapies are now in clinical trials with several more likely to be initiated in the near future. A priori, it can be anticipated that an antibody which broadly recognizes various pathological tau aggregates with high affinity would have the ideal therapeutic properties. Tau antibodies 4E6 and 6B2, raised against the same epitope region but of varying specificity and affinity, were tested for acutely improving cognition and reducing tau pathology in transgenic tauopathy mice and neuronal cultures.Results
Surprisingly, we here show that one antibody, 4E6, which has low affinity for most forms of tau acutely improved cognition and reduced soluble phospho-tau, whereas another antibody, 6B2, which has high affinity for various tau species was ineffective. Concurrently, we confirmed and clarified these efficacy differences in an ex vivo model of tauopathy. Alzheimer’s paired helical filaments (PHF) were toxic to the neurons and increased tau levels in remaining neurons. Both toxicity and tau seeding were prevented by 4E6 but not by 6B2. Furthermore, 4E6 reduced PHF spreading between neurons. Interestingly, 4E6’s efficacy relates to its high affinity binding to solubilized PHF, whereas the ineffective 6B2 binds mainly to aggregated PHF. Blocking 4E6's uptake into neurons prevented its protective effects if the antibody was administered after PHF had been internalized. When 4E6 and PHF were administered at the same time, the antibody was protective extracellularly.Conclusions
Overall, these findings indicate that high antibody affinity for solubilized PHF predicts efficacy, and that acute antibody-mediated improvement in cognition relates to clearance of soluble phospho-tau. Importantly, both intra- and extracellular clearance pathways are in play. Together, these results have major implications for understanding the pathogenesis of tauopathies and for development of immunotherapies.116.
Gene and MicroRNA Expression Are Predictive of Tumor Response in Rectal Adenocarcinoma Patients Treated With Preoperative Chemoradiotherapy 下载免费PDF全文
Caterina Millino Isacco Maretto Beniamina Pacchioni Maura Digito Antonino De Paoli Vincenzo Canzonieri Edoardo D'Angelo Marco Agostini Flavio Rizzolio Antonio Giordano Andrea Barina Senthilkumar Rajendran Giovanni Esposito Gerolamo Lanfranchi Donato Nitti Salvatore Pucciarelli 《Journal of cellular physiology》2017,232(2):426-435
117.
Identification of proteins by mass spectrometry (MS) is an essential step in proteomic studies and is typically accomplished by either peptide mass fingerprinting (PMF) or amino acid sequencing of the peptide. Although sequence information from MS/MS analysis can be used to validate PMF-based protein identification, it may not be practical when analyzing a large number of proteins and when high- throughput MS/MS instrumentation is not readily available. At present, a vast majority of proteomic studies employ PMF. However, there are huge disparities in criteria used to identify proteins using PMF. Therefore, to reduce incorrect protein identification using PMF, and also to increase confidence in PMF-based protein identification without accompanying MS/MS analysis, definitive guiding principles are essential. To this end, we propose a value-based scoring system that provides guidance on evaluating when PMF-based protein identification can be deemed sufficient without accompanying amino acid sequence data from MS/MS analysis. 相似文献
118.
119.
3D Hierarchical Core–Shell Nanostructured Arrays on Carbon Fibers as Catalysts for Direct Urea Fuel Cells 下载免费PDF全文
Bifunctional cobalt oxide (Co3O4) nanowire catalysts grown on carbon cloth (CC) fibers and their modification with nickel oxide (NiO) and manganese dioxide (MnO2) to produce core–shell nanoarchitectures are explored as catalysts for urea oxidation reaction and oxygen reduction reaction in direct urea fuel cells (DUFC). Based on a systematic electrochemical characterization of the catalyst, the as‐developed core–shell nanoarchitectures are optimized toward DUFC performance. Under alkaline conditions with an anion exchange membrane, the DUFC with a cell configuration of Co3O4@NiO(1:2)/CC(a|c)Co3O4@MnO2(1:2)/CC exhibits a maximum power density of 33.8 mW cm?2 with excellent durability for 120 h without any performance loss. Furthermore, the DUFC exhibits a maximum power density of 23.2 mW cm?2 with human urine as a fuel. These findings offer an approach to convert human waste into treasure. 相似文献
120.
Abstract— β- N -Oxalyl- l -α,β-diaminopropionic acid (ODAP), the toxin isolated from the seeds of Luthyrus sativus produces head retraction, tremors and convulsions when injected into a variety of experimental animals. In 12-day-old rats, it has been found that the convulsive behaviour is accompanied by profound biochemical changes in the brain. The brain homogenates prepared from ODAP injected animals show a higher rate of respiration. There is a decrease in the brain glucose, glycogen, ATP, phosphocreatine and acetylcholine levels of the convulsing animals. The inorganic phosphate, lactic acid and acetylcholineesterase levels increase. These results establish that ODAP is a typical convulsant. 相似文献