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241.
The bioconversion potential of two epigeic species (Eisenia foetida Sav. and Eudrilus eugeniae Kinberg) of earthworms was assessed in terms of efficiency and sustainability of vermicomposting of Taro (Colocasia esculenta (Linn) Schott in Schott and Endl). In different vermireactors, each run in triplicates with one of the two species of earthworms, and 60 g of 6:1 Colocasia:cowdung as feed, vermicasts were produced with steadily increasing output in all the reactors. E. eugeniae was found to be more efficient producer of vermicasts than E. foetida. In all reactors, the earthworms grew well, increasing their weights and number. 相似文献
242.
Abdullah M Chai PS Chong MY Tohit ER Ramasamy R Pei CP Vidyadaran S 《Cellular immunology》2012,272(2):214-219
Differences in gender immune response have resulted in differences in immune protection and susceptibility to inflammatory diseases. Cultured peripheral blood mononuclear cells (PBMC) are widely used in immunomodulation studies, yet the influence of gender is usually not considered. We examined the effect of in vitro culture and phytohaemagglutinin (PHA) stimulation on PBMC lymphocyte subsets using flowcytometry. Full blood counts of whole blood showed higher levels of lymphocyte in male subjects. Lymphocyte subsets enumeration revealed higher NK cell counts in males and higher B cells in females. Cultured PBMC resulted in significant increases in B and total T cell percentages among females and NK cells among males. PHA stimulated significantly increased percentages of NK and total T cells in males and total activated T cells (CD69+) in females. Our results showed significant gender differences in lymphocyte subsets in cultured conditions. This may affect experimental outcome. 相似文献
243.
Saminathan R Bai J Sadrolodabaee L Karthik GM Singh O Subramaniyan K Ching CB Chen WN Chowbay B 《PloS one》2010,5(12):e15064
BACKGROUND: Recognizing specific protein changes in response to drug administration in humans has the potential for the development of personalized medicine. Such changes can be identified by pharmacoproteomics approach based on proteomic technologies. It can also be helpful in matching a particular target-based therapy to a particular marker in a subgroup of patients, in addition to the profile of genetic polymorphism. Warfarin is a commonly prescribed oral anticoagulant in patients with prosthetic valve disease, venous thromboembolism and stroke. METHODS AND FINDING: We used a combined pharmacogenetics and iTRAQ-coupled LC-MS/MS pharmacoproteomics approach to analyze plasma protein profiles of 53 patients, and identified significantly upregulated level of transthyretin precursor in patients receiving low dose of warfarin but not in those on high dose of warfarin. In addition, real-time RT-PCR, western blotting, human IL-6 ELISA assay were done for the results validation. CONCLUSION: This combined pharmacogenomics and pharmacoproteomics approach may be applied for other target-based therapies, in matching a particular marker in a subgroup of patients, in addition to the profile of genetic polymorphism. 相似文献
244.
Masakazu Hirasawa Jatindra N. Tripathy Frederik Sommer Ramasamy Somasundaram Jung-Sung Chung Matthew Nestander Mahima Kruthiventi Masoud Zabet-Moghaddam Michael K. Johnson Sabeeha S. Merchant James P. Allen David B. Knaff 《Photosynthesis research》2010,103(2):67-77
The ferredoxin-dependent nitrite reductase from the green alga Chlamydomonas reinhardtii has been cloned, expressed in Escherichia coli as a His-tagged recombinant protein, and purified to homogeneity. The spectra, kinetic properties and substrate-binding parameters of the C. reinhardtii enzyme are quite similar to those of the ferredoxin-dependent spinach chloroplast nitrite reductase. Computer modeling, based on the published structure of spinach nitrite reductase, predicts that the structure of C. reinhardtii nitrite reductase will be similar to that of the spinach enzyme. Chemical modification studies and the ionic-strength dependence of the enzyme’s ability to interact with ferredoxin are consistent with the involvement of arginine and lysine residues on C. reinhardtii nitrite reductase in electrostatically-stabilized binding to ferredoxin. The C. reinhardtii enzyme has been used to demonstrate that hydroxylamine can serve as an electron-accepting substrate for the enzyme and that the product of hydroxylamine reduction is ammonia, providing the first experimental evidence for the hypothesis that hydroxylamine, bound to the enzyme, can serve as a late intermediate during the reduction of nitrite to ammonia catalyzed by the enzyme. 相似文献
245.
The potential of two epigeic species (Eudrilus eugeniae Kinberg, and Perionyx excavatus Perrier) and two anecic species (Lampito mauritii Kinberg and Drawida willsi Michaelson) of earthworms was assessed in terms of efficiency and sustainability of vermicomposting water hyacinth (Eichhornia crassipes, Mart. Solm.). In different vermireactors, each run in duplicate with one of the four species of earthworms, and 75 g of 6:1 water hyacinth:cowdung as feed, vermicasts were produced with steadily increasing output in all the reactors. E. eugeniae was by far the most efficient producer of vermicasts, followed by the other epigeic P. excavatus. The two anecics came next, with D. willsi being the least effective which could generate only about half the quantity of vermicasts achieved in a corresponding time by E. eugeniae. In all the reactors, the earthworms grew well, increasing their weights by more than 250%. The maximum net gain of weight (average 30.7 g) was by E. eugeniae, followed by P. excavatus, L. mauritii and D. willsi. This trend, which followed the efficiency of vermicast production, was also shown in terms of reproductive ability as measured by the number of offspring produced by the four species. 相似文献
246.
Simran K. Jandu Alanah K. Webb Alina Pak Baris Sevinc Daniel Nyhan Alexey M. Belkin Nicholas A. Flavahan Dan E. Berkowitz Lakshmi Santhanam 《Amino acids》2013,44(1):261-269
The multifunctional enzyme tissue transglutaminase (TG2) contributes to the development and progression of several cardiovascular diseases. Extracellular rather than intracellular TG2 is enzymatically active, however, the mechanism by which it is exported out of the cell remains unknown. Nitric oxide (NO) is shown to constrain TG2 externalization in endothelial and fibroblast cells. Here, we examined the role of both exogenous and endogenous (endothelial cell-derived) NO in regulating TG2 localization in vascular cells and tissue. NO synthase inhibition in endothelial cells (ECs) using N-nitro l-arginine methyl ester (l-NAME) led to a time-dependent decrease in S-nitrosation and increase in externalization of TG2. Laminar shear stress led to decreased extracellular TG2 in ECs. S-nitrosoglutathione treatment led to decreased activity and externalization of TG2 in human aortic smooth muscle and fibroblast (IMR90) cells. Co-culture of these cells with ECs resulted in increased S-nitrosation and decreased externalization and activity of TG2, which was reversed by l-NAME. Aged Fischer 344 rats had higher tissue scaffold-associated TG2 compared to young. NO regulates intracellular versus extracellular TG2 localization in vascular cells and tissue, likely via S-nitrosation. This in part, explains increased TG2 externalization and activity in aging aorta. 相似文献
247.
Sivakumar U. Kalaichelvan G. Ramasamy K. 《World journal of microbiology & biotechnology》2004,20(6):563-568
Biodegradation of lignin by Streptomyces spp. results in the production of value-added chemicals such as Acid Precipitable Polymeric Lignins (APPLs), low molecular
weight phenols, etc. To hasten the conversion metabolism through genetic manipulation, a preliminary attempt was made to standardize
the methodology for isolation and regeneration of protoplasts. Protoplast fusion recombinants were developed and assayed for
their ligninolytic activity, production of ligninolytic enzymes viz., peroxidase, laccase, polyphenol oxidase and crude protein. In comparison with the mutants and wild strain, fusion recombinant
F4 showed higher laccase activity and lower peroxidase activity. This attribute can be positively used for polymerization of
free phenolics to polycondensates related to humic acids in soil or composting environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
248.
Mahawar Lovely Pandey Aparna Ramasamy Kesava Priyan Pandey Sakshi Prasad Sheo Mohan 《Journal of applied phycology》2022,34(5):2355-2369
Journal of Applied Phycology - γ-aminobutyric acid (GABA) is a ubiquitous non-protein amino acid widely distributed in prokaryotes and eukaryotes. Recently, it is gaining momentum to treat... 相似文献
249.
Mridul K Kalita Gowthaman Ramasamy Sekhar Duraisamy Virander S Chauhan Dinesh Gupta 《BMC bioinformatics》2006,7(1):336
Background
Genome wide and cross species comparisons of amino acid repeats is an intriguing problem in biology mainly due to the highly polymorphic nature and diverse functions of amino acid repeats. Innate protein repeats constitute vital functional and structural regions in proteins. Repeats are of great consequence in evolution of proteins, as evident from analysis of repeats in different organisms. In the post genomic era, availability of protein sequences encoded in different genomes provides a unique opportunity to perform large scale comparative studies of amino acid repeats. ProtRepeatsDB is a relational database of perfect and mismatch repeats, access to which is designed as a resource and collection of tools for detection and cross species comparisons of different types of amino acid repeats. 相似文献250.
High plasma levels of linoleic acid (18:2) may injure endothelial cells, resulting in decreased barrier function of the vascular endothelium. The effects of linoleic acid on endothelial barrier function (transendothelial movement of albumin), membrane-bound enzyme activities, and possible autooxidation of linoleic acid under experimental conditions were studied. The exposure of endothelial monolayers to 18:2 for 24 hr at 60, 90, and 120 microM fatty acid concentrations caused a significant increase in transendothelial movement of albumin, with maximum albumin transfer at 90 microM. Fatty acid treatment resulted in the increased appearance of cytosolic lipid droplets. Activities of the membrane-bound enzymes, angiotensin-converting enzyme (ACE), and Ca(2+)-ATPase increased steadily with increasing time of cell exposure to 90 microM 18:2, reaching significance at 24 hr. Treatment of endothelial cultures with up to 120 microM 18:2 did not cause cytotoxicity, as evidenced by a nonsignificant change in cellular release of [3H]-adenine. Incubation of 18:2-supplemented serum-containing culture media with 1000 microM 18:2 at 37 degrees C for up to 48 hr did not result in formation of autooxidation products. These results suggest that 18:2 itself, and not its oxidation products, plays a major role in disrupting endothelial barrier function. 相似文献