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121.
A series of novel N-acyl-2-arylethylamines and N-acyl-3-coumarylamines were synthesized and evaluated for their antihyperglycemic activity. Compounds 3g and 6d exhibited lowering of postprandial plasma glucose by 30.7%, 23.3% in SLM and 25.6%, 25.4% in STZ models respectively which is significant compared to metformin and glybenclamide. Other compounds exhibited moderate to good activity ranging from 19.5% to 32.8% in SLM and 3.26% to 25.4% in STZ models.  相似文献   
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The effect of isoproterenol on the levels of serum lipoprotein profile were studied in rats. Rats were treated with isoproterenol (200 mg/100 g body weight, sc twice at an interval of 24 hr) for 2 days. Aspirin was administered orally 1.2 mg/100 g body weight, daily for 60 days. Isoproterenol treated rats showed decrease in the activities of hepatic and extrahepatic lipoprotein lipase. HDL cholesterol level was found to be decreased, significantly with increase in LDL cholesterol in isoproterenol treated rats. Aspirin treated rats showed marked reversal of these metabolic changes. The lipoprotein changes were minimum in rats treated with both aspirin and isoproterenol.  相似文献   
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Abstract The functional significance of charged amino acids of the anion-selective porin Omp34 from Acidovorax delafieldii was investigated by means of conductance measurements. Chemical modification of Lys and Arg as well as titration of charges by adjusting the pH value revealed that positively charged amino acid residues determine the major functional properties of the porin. Positive charges are involved in creating the protein surface potential, the selectivity filter inside the channels, and the voltage-sensing and/or gating mechanisms.  相似文献   
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A spontaneous methyl viologen (MV)-resistant mutant of the nitrogen-fixing cyanobacterium Nostoc punctiforme ATCC 29133 was isolated and the major enzymatic antioxidants involved in combating MV-induced oxidative stress were evaluated. The mutant displayed a high constitutive catalase activity as a consequence of which, the intracellular level of reactive oxygen species in the mutant was lower than the wild type (N. punctiforme) in the presence of MV. The superoxide dismutase (SOD) activity that consisted of a SodA (manganese-SOD) and a SodB (iron-SOD) was not suppressed in the mutant following MV treatment. The mutant was, however, characterised by a lower peroxidase activity compared with its wild type, and its improved tolerance to externally added H2O2 could only be attributed to enhanced catalase activity. Furthermore, MV-induced toxic effects on the wild type such as (1) loss of photosynthetic performance assessed as maximal quantum yield of photosystem II, (2) nitrogenase inactivation, and (3) filament fragmentation and cell lysis were not observed in the mutant. These findings highlight the importance of catalase in preventing MV-promoted oxidative damage and cell death in the cyanobacterium N. punctiforme. Such oxidative stress resistant mutants of cyanobacteria are likely to be a better source of biofertilisers, as they can grow and fix nitrogen in an unhindered manner in agricultural fields that are often contaminated with the herbicide MV, also commonly known as paraquat.  相似文献   
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The present study reports the effect of indanone derivatives on scopolamine induced deficit cholinergic neurotransmission serving as promising leads for the therapeutics of cognitive dysfunction. Eleven compounds 5464 have been designed, synthesised and evaluated against behavioural alterations using step down passive avoidance protocol at a dose of 0.5?mg/kg with Donepezil (1) as the reference standard. All the synthesised compounds were evaluated for their in vitro acetylcholinesterase (AChE) inhibition at five different concentrations using mice brain homogenate as the source of the enzyme. Compounds 54, 56, 59 and 64 displayed appreciable activity with an IC50 value of 14.06?µM, 12.30?µM, 14.06?µM and 12.01?µM, respectively towards acetylcholinesterase inhibition. The molecular docking study performed to predict the binding mode of the compounds suggested that these compounds could bind appreciably to the amino acids present at the active site of recombinant human acetylcholinesterase (rhAChE). The behavioural, biochemical and in silico pharmacokinetic studies were in concordance with each other.  相似文献   
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