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101.
Amarjit Mishra 《Journal of biomedical science》2013,20(1):26
Purinergic P2X7 receptor (P2X7R), an ATP-gated cation channel, is unique among all other family members because of its ability to respond to various stimuli and to modulate pro-inflammatory signaling. The activation of P2X7R in immune cells is absolutely required for mature interleukin -1beta (IL-1beta) and IL-18 production and release. Lung alveoli are lined by the structural alveolar epithelial type I (AEC I) and alveolar epithelial type II cells (AEC II). AEC I plays important roles in alveolar barrier protection and fluid homeostasis whereas AEC II synthesizes and secrete surfactant and prevents alveoli from collapse. Earlier studies indicated that purinergic P2X7 receptors were specifically expressed in AEC I. However, their implication in alveolar functions has not been explored. This paper reviews two important signaling pathways of P2X7 receptors in surfactant homeostatsis and Acute Lung Injury (ALI). Thus, P2X7R resides at the critical nexus of alveolar pathophysiology. 相似文献
102.
Prabhat Kumar Thakur Anil Kumar Mathur Shashi Bala Gautam Chandrajit Balomajumder Rahul 《Bioremediation Journal》2013,17(1):61-70
ABSTRACT A laboratory-scale biofilter unit packed with a mixture of compost, sugarcane bagasse, and granulated activated carbon (GAC) in the ratio of 55:30:15 by weight was used for a biofiltration study of air stream containing benzene, toluene, ethylbenzene, and o-xylene (BTEX). The effect of superficial velocity on mass transfer coefficient for the packing was studied by maintaining gas flow rates of 3, 4, 5, 6, and 8 L min?1 for inlet concentrations of 0.1, 0.4, and 0.8 g m?3 for each of benzene, toluene, ethylbenzene, and o-xylene. The maximum elimination capacity was found to be 20.92, 22.72, 20.73, and 18.94 g m?3 h?1 for BTEX, respectively, for stated flow rates. Removal efficiency of BTEX decreased from 99% to 71% for increasing inlet concentration from 0.1 to 0.8 g m?3. Gas film mass transfer coefficient predicted by modified Onda's equation was within ±10% of the experimental values. 相似文献
103.
Pradyumna K. Mishra Gorantla V. Raghuram Hariom Panwar Deepika Jain Hemant Pandey Kewal K. Maudar 《Free radical research》2013,47(8):718-728
The role of oxidative stress is often attributed in environmental renal diseases. Isocyanates, a ubiquitous chemical group with diverse industrial applications, are known to undergo bio-transformation reactions upon accidental and occupational exposure. This study delineates the role of isocyanate-mediated mitochondrial oxidative stress in eliciting chromosomal instability in cultured human kidney epithelial cells. Cells treated with 0.005 µM concentration of methyl isocyanate displayed morphological transformation and stress-induced senescence. Along the time course, an increase in DCF fluorescence indicative of oxidative stress, depletion of superoxide dismutase (SOD) and glutathione reductase (GR) and consistent accumulation of 8-oxo-dG were noticed. Thus, endogenous oxidative stress resulted in aberrant expression of p53, p21, cyclin E and CDK2 proteins, suggestive of deregulated cell cycle, chromosomal aberrations, centromeric amplification, aneuploidy and genomic instability. 相似文献
104.
Harun Patel Rahul Pawara Iqrar Ansari Harsha Jadhav Sanjay Surana 《Journal of receptor and signal transduction research》2013,33(5-6):393-412
AbstractCardiotoxicity is one amongst the adverse effect of Osimertinib delineate in clinical trials and related to escalating doses. To triumph over the drawbacks of Osimertinib, in this study, we tend to delineate the design, synthesis, in vitro biological analysis of a series of novel reversible selective T790M inhibitors with minimal cardiotoxicity. Amongst the virtually sorted compounds; compound 18 and 74 have been located to be the foremost active compounds of the series with IC50 value of 0.88, 0.92?μM in cellular assay and 0.56, 0.62?μM in enzymatic assay, against double mutant L858R/T790M EGFR. Additionally, they showed much less affinity toward wild-type (WT)-EGFR with minimal cardiotoxicity. 相似文献
105.
Rupesh Kumar Mishra Brajesh Kumar Pandey Vijai Singh Amita John Mathew Neelam Pathak Mohammad Zeeshan 《Journal of microbiology (Seoul, Korea)》2013,51(4):405-412
Twenty one isolates of Fusarium oxysporum f. sp. psidii (Fop), causing a vascular wilt in guava (Psidium guajava L.), were collected from different agro-ecological regions of India. The pathogenicity test was performed in guava seedlings, where the Fop isolates were found to be highly pathogenic. All 21 isolates were confirmed as F. oxysporum f. sp. psidii by a newly developed, species-specific primer against the conserved regions of 28S rDNA and the intergenic spacer region. RAPD and PCR-RFLP were used for genotyping the isolates to determine their genetic relationships. Fifteen RAPD primers were tested, of which five primers produced prominent, polymorphic, and reproducible bands. RAPD yielded an average of 6.5 polymorphic bands per primer, with the amplified DNA fragments ranging from 200–2,000 bp in size. A dendrogram constructed from these data indicated a 22–74% level of homology. In RFLP analysis, two major bands (350 and 220 bp) were commonly present in all isolates of F. oxysporum. These findings provide new insight for rapid, specific, and sensitive disease diagnosis. However, genotyping could be useful in strain-level discrimination of isolates from different agro-ecological regions of India. 相似文献
106.
Nisha Saxena Nimisha Singh Mridul Mishra G. B. Shiva Keshava Praveen Kumar Shukla Rama Pati Tripathi 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):476-482
A series of azatricyclodiones and octahydro-benzo[f]isoindoles have been synthesized by (4+2) Diels-Alder cycloaddition of maleimides with furfuryl amine. Reaction of azatricyclodiones with isocyanates led to the respective ureides. All of the compounds were screened against a number of bacteria and fungi. One of the compounds (2) displayed moderate antitubercular activity while two compounds (2) and (4) inhibited the fungal growth at 25 μg/mL. 相似文献
107.
The present study was designed to investigate the existence of slow and fast developing individuals and to evaluate their effect on reproductive attributes of Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae); a biocontrol agent of Parthenium weed. Significantly different rates of development were found in a cohort of the beetle. Under constant rearing conditions, the emergence ratio of slow and fast developers was determined to be 0.47 and 0.53, respectively. Males developed faster than females, and significant differences in development were found among all immature stages and total developmental period. Slow developing females laid higher numbers of eggs with a higher percentage egg viability than fast developing females. This is the first attempt of such a study for the Parthenium beetle, and provides great insight into Parthenium beetle development for evolutionary biologists, improving our understanding of their ecological thresholds. The information could help in the selection of fast developing lines and thus in the mass multiplication of this bioagent. 相似文献
108.
Ajay Kumar Mishra Perrine Hugon Jean-Christophe Lagier Thi-Tien Nguyen Carine Couderc Didier Raoult Pierre-Edouard Fournier 《Standards in genomic sciences》2013,8(2):290-305
Enorma massiliensis strain phIT is the type strain of E. massiliensis gen. nov., sp. nov., the type species of a new genus within the family Coriobacteriaceae, Enorma gen. nov. This strain, whose genome is described here, was isolated from the fecal flora of a 26-year-old woman suffering from morbid obesity. E. massiliensis strain phIT is a Gram-positive, obligately anaerobic bacillus. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 2,280,571 bp long genome (1 chromosome but no plasmid) exhibits a G+C content of 62.0% and contains 1,901 protein-coding and 51 RNA genes, including 3 rRNA genes. 相似文献
109.
Modeling the activity of glutathione as a hydroxyl radical scavenger considering its neutral non-zwitterionic form 总被引:1,自引:0,他引:1
Glutathione is an immensely important antioxidant, particularly in the central nervous system. The scavenging mechanism of glutathione towards the OH radical was studied theoretically, considering its neutral, non-zwitterionic form relevant to acidic media. Gibbs free barrier and released energies involved in hydrogen abstraction from the different sites of glutathione by an OH radical were studied at the B3LYP/6-31G(d,p), B3LYP/AUG-cc-pVDZ, M06/AUG-cc-pVDZ, M06-2X/AUG-cc-pVDZ levels of density functional theory. Solvation in bulk aqueous media was also studied at all these levels of theory employing the polarizable continuum model. Our study shows that a hydroxyl radical can abstract a hydrogen atom easily from glutathione. Thus, glutathione is shown to be an efficient scavenger of OH radicals, which is in agreement with the results of previous studies. Figure
Hydrogen abstraction (H10) from the most stable conformer of GSH I by a hydroxyl radical 相似文献
110.