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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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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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Lakshmipyari Devi Moirangthem Sudeshna Bhattacharya Karin Stensjö Peter Lindblad Jyotirmoy Bhattacharya 《Applied microbiology and biotechnology》2014,98(8):3809-3818
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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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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Abraham Verghese Suresh Devi Thangam Senthil Kumar Radhakrishnan Nallur Kothandaraman Krishna Kumar Gopalakrishna Pommaiah Shetty 《Biocontrol Science and Technology》2018,28(10):961-969
ABSTRACTConservation biological control is an approach to enhance the efficacy of natural enemies by ensuring their availability in an agro-ecosystem on a long temporal scale. An increased survival often leads to better fecundity and improved behaviour of the natural enemies, which in turn ensures sustainable pest management. This paper, apart from being a concise review of conservation biological control, deals with selected India-specific case studies and field experiences on habitat manipulation and refugia. Results from a Bengaluru-based study during 2012–2015 on conservation biological control in an organic mango ecosystem are also presented. It also dwells briefly on conservation of insectivorous birds and touches upon conservation biocontrol with respect to entomopathogenic microorganisms and plant disease antagonists. 相似文献
130.
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