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371.
Ramovatar Meena Kajal Kumari Jitendra Kumar Paulraj Rajamani H. N. Verma 《Electromagnetic biology and medicine》2014,33(2):81-91
Microwave (MW) radiation produced by wireless telecommunications and a number of electrical devices used in household or in healthcare institutions may adversely affects the reproductive pattern. Present study aimed to investigate the protective effects of melatonin (is well known antioxidant that protects DNA, lipids and proteins from free radical damage) against oxidative stress-mediated testicular impairment due to long-term exposure of MWs. For this, 70-day-old male Wistar rats were divided into four groups (n?=?6/group): Sham exposed, Melatonin (Mel) treated (2?mg/kg), 2.45?GHz MWs exposed and MWs?+?Mel treated. Exposure took place in Plexiglas cages for 2?h a day for 45 days where, power density (0.21?mW/cm2) and specific absorption rate (SAR 0.14?W/Kg) were estimated. After the completion of exposure period, rats were sacrificed and various stress related parameters, that is LDH-X (lactate dehydrogenase isoenzyme) activity, xanthine oxidase (XO), ROS (reactive oxygen species), protein carbonyl content, DNA damage and MDA (malondialdehyde) were performed. Result shows that melatonin prevent oxidative damage biochemically by significant increase (p?0.001) in the levels of testicular LDH-X, decreased (p?0.001) levels of MDA and ROS in testis (p?0.01). Meanwhile, it reversed the effects of MWs on XO, protein carbonyl content, sperm count, testosterone level and DNA fragmentation in testicular cells. These results concluded that the melatonin has strong antioxidative potential against MW induced oxidative stress mediated DNA damage in testicular cells. 相似文献
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374.
Terrestrial contribution of dissolved organic carbon (DOC) to riverine carbon transport remains relatively uncertain despite recent research highlighting its importance. Here we present data on changing state of atmosphere–land–water transfer and associated shift in DOC build-up in Ganga River (India) for a period of 6 years (March, 2007–February, 2013). Although the N:P stoichiometry of atmospheric deposition (AD) showed a declining trend, there was over 1.4 to 1.6-fold increase in AD-NO3 ?, 1.5 to 1.8-fold increase in AD-OC and, over 1.5 to 2.2-fold increase in AD-NH4 + and AD-PO4 3? input over time. Water soluble organic carbon and microbial activity in sub-catchments and, DOC and nutrient concentrations in runoff increased consistently over time along the gradient of AD-input. We found a variable but strong linkage between atmospheric deposition and hydrological control of terrestrial carbon and nutrient input to the river. The results showed that the increasing input of AD-nutrients enhance primary production whereas, such input in sub-catchment enhance DOC in runoff and, the coupled effect of these favor DOC build-up in Ganga River at Varanasi. The study that forms the first report establishing trans-boundary drivers of DOC in Ganga River suggests that future climate model should consider large scale inter-regional time series data on changing atmosphere–land–water transfer and associated shift in carbon balance of major rivers for more accurately predicting cross-domain carbon linkages and planning for integrated river basin management. 相似文献
375.
Sundar Srinivasan Brandon J. Ausk Jitendra Prasad Dewayne Threet Steven D. Bain Thomas S. Richardson Ted S. Gross 《PLoS computational biology》2010,6(9)
The increasing incidence of osteoporosis worldwide requires anabolic treatments that are safe, effective, and, critically, inexpensive given the prevailing overburdened health care systems. While vigorous skeletal loading is anabolic and holds promise, deficits in mechanotransduction accrued with age markedly diminish the efficacy of readily complied, exercise-based strategies to combat osteoporosis in the elderly. Our approach to explore and counteract these age-related deficits was guided by cellular signaling patterns across hierarchical scales and by the insight that cell responses initiated during transient, rare events hold potential to exert high-fidelity control over temporally and spatially distant tissue adaptation. Here, we present an agent-based model of real-time Ca2+/NFAT signaling amongst bone cells that fully described periosteal bone formation induced by a wide variety of loading stimuli in young and aged animals. The model predicted age-related pathway alterations underlying the diminished bone formation at senescence, and hence identified critical deficits that were promising targets for therapy. Based upon model predictions, we implemented an in vivo intervention and show for the first time that supplementing mechanical stimuli with low-dose Cyclosporin A can completely rescue loading induced bone formation in the senescent skeleton. These pre-clinical data provide the rationale to consider this approved pharmaceutical alongside mild physical exercise as an inexpensive, yet potent therapy to augment bone mass in the elderly. Our analyses suggested that real-time cellular signaling strongly influences downstream bone adaptation to mechanical stimuli, and quantification of these otherwise inaccessible, transient events in silico yielded a novel intervention with clinical potential. 相似文献
376.
Kumar J Choudhary BC Metpally R Zheng Q Nonet ML Ramanathan S Klopfenstein DR Koushika SP 《PLoS genetics》2010,6(11):e1001200
UNC-104/KIF1A is a Kinesin-3 motor that transports synaptic vesicles from the cell body towards the synapse by binding to PI(4,5)P(2) through its PH domain. The fate of the motor upon reaching the synapse is not known. We found that wild-type UNC-104 is degraded at synaptic regions through the ubiquitin pathway and is not retrogradely transported back to the cell body. As a possible means to regulate the motor, we tested the effect of cargo binding on UNC-104 levels. The unc-104(e1265) allele carries a point mutation (D1497N) in the PI(4,5)P(2) binding pocket of the PH domain, resulting in greatly reduced preferential binding to PI(4,5)P(2)in vitro and presence of very few motors on pre-synaptic vesicles in vivo. unc-104(e1265) animals have poor locomotion irrespective of in vivo PI(4,5)P(2) levels due to reduced anterograde transport. Moreover, they show highly reduced levels of UNC-104 in vivo. To confirm that loss of cargo binding specificity reduces motor levels, we isolated two intragenic suppressors with compensatory mutations within the PH domain. These show partial restoration of in vitro preferential PI(4,5)P(2) binding and presence of more motors on pre-synaptic vesicles in vivo. These animals show improved locomotion dependent on in vivo PI(4,5)P(2) levels, increased anterograde transport, and partial restoration of UNC-104 protein levels in vivo. For further proof, we mutated a conserved residue in one suppressor background. The PH domain in this triple mutant lacked in vitro PI(4,5)P(2) binding specificity, and the animals again showed locomotory defects and reduced motor levels. All allelic variants show increased UNC-104 levels upon blocking the ubiquitin pathway. These data show that inability to bind cargo can target motors for degradation. In view of the observed degradation of the motor in synaptic regions, this further suggests that UNC-104 may get degraded at synapses upon release of cargo. 相似文献
377.
Gadd ME Broekemeier KM Crouser ED Kumar J Graff G Pfeiffer DR 《The Journal of biological chemistry》2006,281(11):6931-6939
The mitochondrial Ca(2+)-independent phospholipase A(2) is activated during energy-dependent Ca(2+) accumulation under conditions where there is a sustained depression of the membrane potential. This activation is not dependent on induction of the mitochondrial permeability transition. Bromoenol lactone, which inhibits the phospholipase, is effective as an inhibitor of the transition, and this action can be overcome by low levels of exogenous free fatty acids. Apparently, activation of the Ca(2+)-independent phospholipase is a factor in the mechanisms by which depolarization and Ca(2+) accumulation promote opening of the permeability transition pore. Sustained activity of the Ca(2+)-independent phospholipase A(2) promotes rupture of the outer mitochondrial membrane and spontaneous release of cytochrome c on a time scale similar to that of apoptosis occurring in cells. However, more swelling of the matrix space must occur to provoke release of a given cytochrome c fraction when the enzyme is active, compared with when it is inhibited. Through its effects on the permeability transition and release of intermembrane space proteins, the mitochondrial Ca(2+)-independent phospholipase A(2) may be an important factor governing cell death caused by necrosis or apoptosis. 相似文献
378.
379.
V. Ravi Jitendra P. Khurana Akhilesh K. Tyagi Paramjit Khurana 《Tree Genetics & Genomes》2006,3(1):49-59
The complete nucleotide sequence of mulberry (Morus indica cv. K2) chloroplast genome (158,484 bp) has been determined using a combination of long PCR and shotgun-based approaches. This is the third angiosperm tree species whose plastome sequence has been completely deciphered. The circular double-stranded molecule comprises of two identical inverted repeats (25,678 bp each) separating a large and a small single-copy region of 87,386 bp and 19,742 bp, respectively. A total of 83 protein-coding genes including five genes duplicated in the inverted repeat regions, eight ribosomal RNA genes and 37 tRNA genes (30 gene species) representing 20 amino acids, were assigned on the basis of homology to predicted genes from other chloroplast genomes. The mulberry plastome lacks the genes infA, sprA, and rpl21 and contains two pseudogenes ycf15 and ycf68. Comparative analysis, based on sequence similarity, both at the gene and genome level, indicates Morus to be closer to Cucumis and Lotus, phylogenetically. However, at genome level, inclusion of non-coding regions brings it closer to Eucalyptus, followed by Cucumis. This may reflect differential selection pressure operating on the genic and intergenic regions of the chloroplast genome.Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.Communicated by Y. Tsumura 相似文献
380.
Lalit?Kumar?Gautam Mohit?Yadav Jitendra?Singh?RathoreEmail author 《Journal of molecular modeling》2017,23(6):189
Toxin–antitoxin (TA) complexes play an important role in stress responses and programmed cell death in bacteria. The RelB-RelE toxin antitoxin system is well studied in Escherichia coli. In this study, we used combined in silico and in vitro approaches to study a novel Xn-RelT toxin from Xenorhabdus nematophila bearing its own antitoxin Xn-RelAT—a RelB homolog of E. coli. The structure for this toxin–antitoxin pair is yet unknown. We generated homology-based models of X. nematophila RelT toxin and antitoxin. The deduced models were further characterized for protein–nucleic acid, protein–protein interactions and gene ontology. A detrimental effect of recombinant Xn-RelT on host E. coli was determined through endogenous toxicity assay. When expressed from a isopropyl β-d-1-thiogalactopyranoside-regulated LacZ promoter, Xn-RelT toxin showed a toxic effect on E. coli cells. These observations imply that the conditional cooperativity governing the Xn-RelT TA operon in X. nematophila plays an important role in stress management and programmed cell death. 相似文献