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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
104.
Vasandra Devi Karthigesu Maimuna Mendy Marijke Fortuin Hilton C. Whittle Colin R. Howard Lisa M.C. Allison 《FEMS microbiology letters》1995,131(2):127-132
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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Poonam Piplani Ankit Jain Dhiksha Devi Anuradha Sharma Pragati Silakari 《Bioorganic & medicinal chemistry》2018,26(1):215-224
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 54–64 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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The world’s increasing population and shortage of food and feed is creating an urgently for us to look for new protein sources from waste products like keratinous waste. Poor management of these wastes has made them one of the major recalcitrant pollutants in nature. Microbial keratinases offers an economic and eco-friendly alternative for degrading and recycling keratinous waste into valuable byproducts. Diverse groups of microorganisms viz., bacteria, fungi and actinomycetes have the ability to degrade recalcitrant keratin by producing keratinase enzyme. Microbial keratinases exhibits great diversity in its biochemical properties with respect to activity and stability in various pH and temperature ranges as well as in the range of recalcitrant proteins it degrades like those present in feathers, hairs, nails, hooves etc. Owing to diverse properties and multifarious biotechnological implications, keratinases can be considered as promising biocatalysts for preparation of animal nutrients, protein supplements, leather processing, fiber modification, detergent formulation, feather meal processing for feed and fertilizer, the pharmaceutical, cosmetic and biomedical industries, and waste management. This review article presents an overview of keratin structure and composition, mechanism of microbial keratinolysis, diversity of keratinolytic microorganisms, and their potential applications in various fields. 相似文献
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Seyed Fazel Nabavi Antoni Sureda Ahmad Reza Dehpour Samira Shirooie Ana Sanches Silva Kasi Pandima Devi Touqeer Ahmed Nafeesa Ishaq Rabia Hashim Eduardo Sobarzo-Sánchez Maria Daglia Nady Braidy Mariateresa Volpicella Rosa Anna Vacca Seyed Mohammad Nabavi 《Biotechnology advances》2018,36(6):1768-1778
In the present paper, we will discuss on the importance of autophagy in the central nervous system, and outline the relation between autophagic pathways and the pathogenesis of neurodegenerative disorders. The potential therapeutic benefits of naturally occurring phytochemicals as pharmacological modulators of autophagy will also be addressed. Our findings provide renewed insight on the molecular modes of protection by polyphenols, which is likely to be at least in part mediated not only by their potent antioxidant and anti-inflammatory effects, but also through modulation of autophagic processes to remove the aberrant protein aggregates. 相似文献
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Singh Rajendra Pandey Deepak Devi Neena Chand Duni 《Bioprocess and biosystems engineering》2018,41(8):1225-1232
Bioprocess and Biosystems Engineering - Butyramide is a commodity chemical having wide range of applications from material science to biological sciences including synthesis of therapeutic drugs,... 相似文献
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Suman Keerthi Uma Devi Koduru Subrahmanya Sarma Nittala Narasimha Reddy Parine 《Saudi Journal of Biological Sciences》2018,25(7):1411-1419
Halophilic microbes are studied to understand the metabolic pathways adopted by organisms in such extreme environment and for their biotechnological exploitation. In thallosohaline environments worldwide, the autotrophic alga Dunaliella salina Teodoresco is omnipresent, but it is being recently realised that the heterotrophic components vary in different regions. The unexplored eastern coastline of India abutted by Bay of Bengal was investigated for the heterotrophic halophilic microbes in this region. The waters in the salterns – replicas of natural hyper-saline water bodies of that region, were collected at four sites along 650 km of the coastal belt. In cultures set up from these waters, green and pink colonies were observed. The green colonies were found to be those of D. salina while the pink colonies were of heterotrophs. To identify the heterotrophic microbes, light microscopy, 16S rRNA typing and pigment profiling through spectrophotometry and HPLC were done. The cells in pink colonies were rod shaped. 16S rRNA typing of cells in these colonies detected the presence of Halomonas sp. – a eubacterium. The pigment profile of cells in pink cultures matched that of the archaea – Halobacterium; bacterioruberin derivatives were found. Thus, it was concluded that Halomonas and Halobacterium spp. are among the co-inhabitant heterotrophs of D. salina. Cultures of D. salina established from these salterns showed the typical three colours seen in the ponds of different sub-plots of salterns. They were green until 30 days, turning dark orange by 60 days and pink when 90 day old. In the 90 day old cultures, innumerable rod shaped cells were found. These cells were similar to the cells of the waters from the ponds of pink sub-plots of salterns and the pink colonies established from saltern waters in the laboratory. In the old (90 days) laboratory cultures of D. salina, the glycerol and proteins released from degenerating cells and the increase in salt concentration to super saturation levels due to evaporation of water in the medium led to the gregarious appearance of the heterotrophs – the co-inhabitants in natural environment. 相似文献