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291.
Microbial diseases in fish, plant, animal and human are rising constantly; thus, discovery of their antidote is imperative. The use of antibiotic in aquaculture further compounds the problem by development of resistance and consequent consumer health risk by bio-magnification. Antimicrobial peptides (AMPs) have been highly promising as natural alternative to chemical antibiotics. Though AMPs are molecules of innate immune defense of all advance eukaryotic organisms, fish being heavily dependent on their innate immune defense has been a good source of AMPs with much wider applicability. Machine learning-based prediction method using wet laboratory-validated fish AMP can accelerate the AMP discovery using available fish genomic and proteomic data. Earlier AMP prediction servers are based on multi-phyla/species data, and we report here the world’s first AMP prediction server in fishes. It is freely accessible at http://webapp.cabgrid.res.in/fishamp/. A total of 151 AMPs related to fish collected from various databases and published literature were taken for this study. For model development and prediction, N-terminus residues, C-terminus residues and full sequences were considered. Best models were with kernels polynomial-2, linear and radial basis function with accuracy of 97, 99 and 97 %, respectively. We found that performance of support vector machine-based models is superior to artificial neural network. This in silico approach can drastically reduce the time and cost of AMP discovery. This accelerated discovery of lead AMP molecules having potential wider applications in diverse area like fish and human health as substitute of antibiotics, immunomodulator, antitumor, vaccine adjuvant and inactivator, and also for packaged food can be of much importance for industries.  相似文献   
292.
Green and blue mold postharvest diseases are the most vital negative components influencing the local market of citrus fruits. Citrus fruits were collected, and fungi were isolated. Among the fungal isolates identified, Penicillium digitatum and Penicillium italicum recorded the highest occurrence of 39.5 and 25.6%, respectively. In this work, we extracted chitosan from Aspergillum niger ATCC 9642. Fourier transform infrared spectroscopy was utilized to confirm the functional groups of the obtained compound, which exhibited the main characteristic bands of O–H stretching at 3302 cm-1, and C–O–C band at 1125 cm-1. A. niger ATCC 9642 chitosan had the degree of deacetylation of 88.5%, a molecular weight of 1.8 × 105 Da, and viscosity of 7.3 centipoises; these values were comparable to those for standard shrimp chitosan. Ultraviolet-visible light spectra revealed the presence of A. niger ATCC 9642 chitosan-AgNPs composite. Using antifungal and spore germination assays, it was found that this composite exhibited effective antifungal action against P. digitatum and P. italicum compared with a chitosan standard. In a comet assay, the percentage of tail DNA was considered as a parameter that indicated DNA damage. The comet parameter increased significantly (P < 0.05) with A. niger ATCC 9642 chitosan–AgNPs composite, and the increase was dose-dependent. The increase in the DNA damage positively correlated with the inhibition performance of the A. niger ATCC 9642 chitosan–AgNPs composite.  相似文献   
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The appearance and disappearance of 15-keto-13,14-dihydro-PGF and 11-ketotetranor PGF metabolites have been measured in the blood and urine of the mare following i.v. injection of prostaglandin F (PGF). The basal plasma concentration of the 11-ketotetranor PGF metabolites was 10-fold greater than 15-keto-13,14-dihydro PGF; after injection of PGF, however, 15-keto-13,14-dihydro PGF increased rapidly to concentrations exceeding those of the 11-ketotetranor PGF metabolites, which also increased but to a much lesser extent. The half-life for the disappearance of 15-keto-13,14-dihydro PGF was about 30-fold shorter than that of the 11-ketotetranor PGF metabolites. Similar profiles were seen in the urine, except that the concentration of the 11-ketotetranor PGF metabolites was always greater than that of the 15-keto-13,14-dihydro PGF. In the mare, the main plasma metabolite of PGF appears to be 15-keto-13,14-dihydro PGF, whereas the 11-ketotetranor PGF metabolites predominate in the urine.Similar patterns were seen for both types of metabolite in the plasma during luteolysis and early pregnancy. Because of the differences in rates of appearance and disappearance of these metabolites, measurement of both allows the detection of peaks of PGF release in samples taken less frequently than is necessary when either type is measured alone.  相似文献   
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Catechol derived siderophores are the most powerful currently known iron chelators. We have intended tripodal ligands built with o,o′ dihydroxy biaryl subunits (A, B, and C). We described antioxidant properties of this new family of iron chelators. Superoxidedependent hydroxyl radical system was used. Peroxidation of different lipid-containing systems (liposomes, erythrocyte membrane ghosts, tissue homogenates) were also investigated. The antioxidant properties of these new chelators have been related to that of desferrioxamine, as a reference compound. In general manner, the results depended mainly on the model used in the assay. However, C presents an antioxidant effect close to that of desferrioxamine.  相似文献   
297.
Parkinson's disease is the most common movement disorder characterized by dopaminergic dysfunction and degeneration. Loss-of-function mutations in the DJ-1 gene have been linked to autosomal recessive forms of early-onset familial Parkinson's disease. DJ-1 is thought to play roles in protection of cells against oxidative stress and in maintenance of the normal dopaminergic function in the nigrostriatal pathway. Here we investigate the consequence of both DJ-1 inactivation and aging in mice. We found that DJ-1-/- mice at the age of 24–27 months have normal numbers of dopaminergic neurons in the substantia nigra and normal levels of dopamine and its major metabolites in the striatum. The number of noradrenergic neurons in the locus coeruleus is also unchanged in DJ-1-/- mice. Moreover, there is no accumulation of oxidative damage or inclusion bodies in aged DJ-1-/- brains. Together, these results indicate that loss of DJ-1 function alone is insufficient to cause nigral degeneration and oxidative damage in the life span of mice.  相似文献   
298.
There is increasing evidence that multivalency plays an important role in protein-lipid recognition and membrane targeting in biological systems. We describe here the preparation and characterization of multivalent analogues of the signaling lipid phosphatidylinositol-4,5-bisphosphate (PIP2). Tetherable analogues of the PIP2 headgroup were appended to polyamidoamine dendrimers via a squarate linker to afford polymers displaying four or eight headgroup moieties. This class of molecules should provide a powerful tool for the study of protein-lipid interactions.  相似文献   
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Chiral stationary phases are conveniently used for enantiomeric separation of drugs by liquid chromatography. Consumption of large volumes of hazardous solvents is considered as a common challenge for the sustainability of this technique. To this end, a columnar chromatography has been adopted using 50‐mm‐length stationary phases. The study comprised five Phenomenex Lux cellulose‐ and amylose‐based columns for the separation of guaifenesin (GUA) enantiomers. In addition, an experimental design was used to optimize the gradient profile for the separation of racemic GUA and ambroxol HCl (AMB) binary mixture. The chromatographic method was achieved using Lux Cellulose‐1 (50 × 4.6 mm) as a chiral stationary phase and ethanol/water as a mobile phase with linear gradient elution of 20% to 70% ethanol in 6 minutes at a flow rate of 1.0 mL min?1 and UV detection at 270 nm. Linearity ranges were found to be 50 to 1000 μg mL?1 and 15 to 450 μg mL?1 for each GUA enantiomer and AMB, respectively. Environmental, health and safety tool was used to assess and compare greenness of the proposed and reported methods. Short column indeed reduces the environmental impact by decreasing waste by about 60% and utilizing only 1‐mL ethanol in the mobile phase. The proposed method is a safer alternative for the simultaneous determination of drugs in their combined pharmaceutical formulation. The method has been validated and compared favorably with a reported one.  相似文献   
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