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21.
Lord Wasim Reza Srinath Satyanarayna Donald A. Enarson Ajay M. V. Kumar Karuna Sagili Sujeet Kumar Levi Anand Prabhakar N. M. Devendrappa Ashish Pandey Nevin Wilson Sarabjit Chadha Badri Thapa Kuldeep Singh Sachdeva Mohan P. Kohli 《PloS one》2013,8(10)
Background
Light-emitting diode fluorescence microscopy (LED-FM) has been shown to be more sensitive than conventional bright field microscopy using Ziehl-Neelsen (ZN) stain in detecting sputum smear positive tuberculosis in controlled laboratory conditions. In 2012, Auramine O staining based LED-FM replaced conventional ZN microscopy in 200 designated microscopy centres (DMC) of medical colleges operating in collaboration with India’s Revised National Tuberculosis Control Programme. We aimed to assess the impact of introduction of LED-FM services on sputum smear positive case detection under program conditions.Methods
This was a before and after comparison study. In 15 randomly selected medical college DMCs, all presumptive TB patients who underwent sputum smear examination in the years 2011 (before LED-FM) and 2012 (after LED-FM) were compared. An additional 15 comparable DMCs that implemented conventional ZN sputum smear microscopy were also selected for comparison between 2011 and 2012.Results
The proportion of presumptive TB patients (PTP)found sputum smear positive increased by 30%- from 13.6% (3432/25159) in 2011 to 17.8% (4706/26426) in 2012 (P value <0.01) in the sites that implemented LED-FM microscopy, whereas in DMCs where the ZN staining procedure is followed the proportion of sputum smear positive had remained unchanged (13.0%versus 12.6%;P value0.31).Conclusion
Use of LED-FM significantly increased the proportion of smear positive cases among presumptive TB patients under routine program conditions in high workload laboratories. The study provides operational evidence needed to scale-up the use of LED-FM in similar settings in India and beyond. 相似文献22.
Kuppan Saravanan Chad W. Mason Ashish Rudola Kim Hai Wong Palani Balaya 《Liver Transplantation》2013,3(4):444-450
Sodium ion batteries are attractive for the rapidly emerging large‐scale energy storage market for intermittent renewable resources. Currently a viable cathode material does not exist for practical non‐aqueous sodium ion battery applications. Here we disclose a high performance, durable electrode material based on the 3D NASICON framework. Porous Na3V2(PO4)3/C was synthesized using a novel solution‐based approach. This material, as a cathode, is capable of delivering an energy storage capacity of ~400 mWh/g vs. sodium metal. Furthermore, at high current rates (10, 20 and 40 C), it displayed remarkable capacity retention. Equally impressive is the long term cycle life. Nearly 50% of the initial capacity was retained after 30,000 charge/discharge cycles at 40 C (4.7 A/g). Notably, coulombic efficiency was 99.68% (average) over the course of cycling. To the best of our knowledge, the combination of high energy density, high power density and ultra long cycle life demonstrated here has never been reported before for sodium ion batteries. We believe our findings will have profound implications for developing large‐scale energy storage systems for renewable energy sources. 相似文献
23.
Singh Ashish Tripathi Pratibha Yadawa Arun Kumar Singh Sarika 《Neurochemical research》2020,45(8):1731-1745
Neurochemical Research - Parkinson’s disease (PD) is a slow progressive, second most common neurodegenerative disease characterized by the loss of dopaminergic neurons from the nigrostriatal... 相似文献
24.
Neurochemical Research - The present study demonstrates the epigenetic mechanisms underlying the effect of Bacoside rich extract of Bacopa monniera—a nootropic herb, on scopolamine treated... 相似文献
25.
Monika Chaudhary Neeraj Kumar Ashish Baldi Ramesh Chandra M. Arockia Babu 《Journal of biomolecular structure & dynamics》2020,38(1):200-218
AbstractWith an endeavor to develop novel curcumin analogs as potential anti-cancer agents, we designed and synthesized a series of Knoevenagel condensates by clubbing pyrazole carbaldehydes at the active methylene carbon atom of the curcumin backbone. Molecular docking studies were carried out to target the proposed derivatives on human kinase β (IKKβ), a potential anti-cancer target. The chloro derivative displayed five hydrogen bond interactions with a docking score of ?11.874?kcal/mol higher than curcumin (docking score =??7.434?kcal/mol). This was supported by the fact that the propellant shaped derivatives fitted aptly into the binding pocket. Molecular simulations studies were also conducted on the lead molecule and the results figured out that the stable complexes were developed as the minimal deviations per residue of protein within the range of 0.11–0.92 Å. The screened compounds were synthesized, characterized and evaluated in vitro for cytotoxicity against cervical cancer cell line, HeLa using standard cell proliferation assay. Chloro derivative and bromo analog demonstrated IC50 (half maximal inhibitory concentration) value of 14.2 and 18.6 µg/ml, respectively, significantly lower than 42.4 µg/ml of curcumin and higher than 0.008 µg/ml of paclitaxel. Induction of apoptosis was evaluated in the terms of cleavage of caspase-3 enzyme and they also exhibited 69.6 and 65.4% of apoptosis significantly higher than 19.9% induced by curcumin. In conclusion, chloro and bromo derivatives must be evaluated under a set of stringent in vitro and in vivo parameters for translating in to a clinically viable product.Communicated by Ramaswamy H. Sarma 相似文献
26.
Suman Kundu Talat Roome Ashish Bhattacharjee Kevin A. Carnevale Valentin P. Yakubenko Renliang Zhang Sung Hee Hwang Bruce D. Hammock Martha K. Cathcart 《Journal of lipid research》2013,54(2):436-447
Monocyte chemoattractant protein-1 (MCP-1)-induced monocyte chemotaxis is a major event in inflammatory disease. Our prior studies have demonstrated that MCP-1-dependent chemotaxis requires release of arachidonic acid (AA) by activated cytosolic phospholipase A2 (cPLA2). Here we investigated the involvement of AA metabolites in chemotaxis. Neither cyclooxygenase nor lipoxygenase pathways were required, whereas pharmacologic inhibitors of both the cytochrome-P450 (CYP) and the soluble epoxide hydrolase (sEH) pathways blocked monocyte chemotaxis to MCP-1. To verify specificity, we demonstrated that the CYP and sEH products epoxyeiscosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs), respectively, restored chemotaxis in the presence of the inhibitors, indicating that sEH-derived products are essential for MCP-1-driven chemotaxis. Importantly, DHETs also rescued chemotaxis in cPLA2-deficient monocytes and monocytes with blocked Erk1/2 activity, because Erk controls cPLA2 activation. The in vitro findings regarding the involvement of CYP/sEH pathways were further validated in vivo using two complementary approaches measuring MCP-1-dependent chemotaxis in mice. These observations reveal the importance of sEH in MCP-1-regulated monocyte chemotaxis and may explain the observed therapeutic value of sEH inhibitors in treatment of inflammatory diseases, cardiovascular diseases, pain, and even carcinogenesis. Their effectiveness, often attributed to increasing EET levels, is probably influenced by the impairment of DHET formation and inhibition of chemotaxis. 相似文献
27.
David F. Stowe Ashish K. Gadicherla Yifan Zhou Mohammed Aldakkak Qunli Cheng Wai-Meng Kwok Ming Tao Jiang James S. Heisner MeiYing Yang Amadou K.S. Camara 《生物化学与生物物理学报:生物膜》2013,1828(2):427-442
We tested if small conductance, Ca2 +‐sensitive K+ channels (SKCa) precondition hearts against ischemia reperfusion (IR) injury by improving mitochondrial (m) bioenergetics, if O2‐derived free radicals are required to initiate protection via SKCa channels, and, importantly, if SKCa channels are present in cardiac cell inner mitochondrial membrane (IMM). NADH and FAD, superoxide (O2?), and m[Ca2 +] were measured in guinea pig isolated hearts by fluorescence spectrophotometry. SKCa and IKCa channel opener DCEBIO (DCEB) was given for 10 min and ended 20 min before IR. Either TBAP, a dismutator of O2?, NS8593, an antagonist of SKCa isoforms, or other KCa and KATP channel antagonists, were given before DCEB and before ischemia. DCEB treatment resulted in a 2-fold increase in LV pressure on reperfusion and a 2.5 fold decrease in infarct size vs. non-treated hearts associated with reduced O2? and m[Ca2 +], and more normalized NADH and FAD during IR. Only NS8593 and TBAP antagonized protection by DCEB. Localization of SKCa channels to mitochondria and IMM was evidenced by a) identification of purified mSKCa protein by Western blotting, immuno-histochemical staining, confocal microscopy, and immuno-gold electron microscopy, b) 2-D gel electrophoresis and mass spectroscopy of IMM protein, c) [Ca2 +]‐dependence of mSKCa channels in planar lipid bilayers, and d) matrix K+ influx induced by DCEB and blocked by SKCa antagonist UCL1684. This study shows that 1) SKCa channels are located and functional in IMM, 2) mSKCa channel opening by DCEB leads to protection that is O2? dependent, and 3) protection by DCEB is evident beginning during ischemia. 相似文献
28.
Ashish Sharma Babita Patni Deepti Shankhdhar S. C. Shankhdhar 《Physiology and Molecular Biology of Plants》2013,19(1):11-20
Availability of Zn to plant is hampered by its immobile nature and adverse soil conditions. Thus, Zn deficiency is observed even though high amount is available in soil. Root-shoot barrier, a major controller of zinc transport in plant is highly affected by changes in the anatomical structure of conducting tissue and adverse soil conditions like pH, clay content, calcium carbonate content, etc. Zn deficiency results in severe yield losses and in acute cases plant death. Zn deficiency in edible plant parts results in micronutrient malnutrition leading to stunted growth and improper sexual development in humans. To overcome this problem several strategies have been used to enrich Zn availability in edible plant parts, including nutrient management, biotechnological tools, and classical and molecular breeding approaches. 相似文献
29.
P Sharma SK Tuteja V Bhalla G Shekhawat VP Dravid CR Suri 《Biosensors & bioelectronics》2013,39(1):99-105
We report a novel in-situ electrochemical synthesis approach for the formation of functionalized graphene-graphene oxide (fG-GO) nanocomposite on screen-printed electrodes (SPE). Electrochemically controlled nanocomposite film formation was studied by transmission electron microscopy (TEM) and Raman spectroscopy. Further insight into the nanocomposite has been accomplished by the Fourier transformed infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD) spectroscopy. Configured as a highly responsive screen-printed immunosensor, the fG-GO nanocomposite on SPE exhibits electrical and chemical synergies of the nano-hybrid functional construct by combining good electronic properties of functionalized graphene (fG) and the facile chemical functionality of graphene oxide (GO) for compatible bio-interface development using specific anti-diuron antibody. The enhanced electrical properties of nanocomposite biofilm demonstrated a significant increase in electrochemical signal response in a competitive inhibition immunoassay format for diuron detection, promising its potential applicability for ultra-sensitive detection of range of target analytes. 相似文献
30.
Ashish K. Rehni Thakur Gurjeet Singh 《Journal of trace elements in medicine and biology》2013,27(1):31-39
ProjectSelenium deficiency has been associated with enhanced propensity of seizures in man and laboratory animals. Therefore, the present study has been designed to investigate the anti-convulsant effect of sodium selenite and seleno-dl-methionine on pentylenetetrazole induced seizures in mice and the role of prostaglandin receptor activation in the proposed anticonvulsant effect of sodium selenite.ProcedureSodium selenite (1, 3 and 10 mg kg?1, i.p.) and seleno-dl-methionine (0.3, 1 and 3 mg kg?1, i.p.) was used to evaluate the potential effect on pentylenetetrazole induced seizures in mice. Pentylenetetrazole induced seizures were assessed in terms of onset time of straub's tail phenomenon, jerky movements of the whole body and convulsions. Additionally, an isobolographic study design was used to examine the interaction between sodium selenite and celecoxib (a cyclooxygenase-2 inhibitor). Sodium selenite and seleno-dl-methionine significantly attenuated pentylenetetrazole induced seizures in mice.ResultsPrior administration of misoprostol (a selective agonist of prostaglandin E1 receptors) markedly attenuated the anticonvulsant effect of sodium selenite as well as seleno-dl-methionine in mice. However, the administration of misoprostol per se did not produce any behavioral changes. Further, sodium selenite was observed to exert a synergistic interaction with celecoxib.ConclusionsSelenium induced reduction in seizure like behavior might be ascribed to the activation of a prostaglandin E1 receptor activation linked mechanism. It is further proposed that sodium selenite exerts a synergistic anti-convulsant effect with celecoxib indicating the therapeutic usefulness of combining the two agents to treat epilepsy. 相似文献