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Stacy Van Epps Bryan Fiamengo Jeremy Edmunds Anna Ericsson Kristine Frank Michael Friedman Dawn George Jonathan George Eric Goedken Brian Kotecki Gloria Martinez Philip Merta Michael Morytko Shashank Shekhar Barbara Skinner Kent Stewart Jeffrey Voss Grier Wallace Neil Wishart 《Bioorganic & medicinal chemistry letters》2013,23(3):693-698
Interest in therapeutic kinase inhibitors continues to grow beyond success in oncology. To date, ATP-mimetic kinase inhibitors have focused primarily on monocyclic and bicyclic heterocyclic cores. We sought to expand on the repertoire of potential cores for kinase inhibition by exploring tricyclic variants of classical bicyclic hinge binding motifs such as pyrrolopyridine and pyrrolopyrazine. Herein we describe the syntheses of eight alternative tricyclic cores as well as in vitro screening results for representative kinases of potential therapeutic interest. 相似文献
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Chandra Bhushan Mishra Dimpy Sharma Amresh Prakash Namrata Kumari Nitin Kumar Pratibha Mehta Luthra 《Bioorganic & medicinal chemistry》2013,21(19):6077-6083
Novel 2-thioxothiazole derivatives (6–19) as potential adenosine A2A receptor (A2AR) antagonists were synthesized. The strong interaction of the compounds (6–19) with A2AR in docking study was confirmed by high binding affinity with human A2AR expressed in HEK293T cells using radioligand-binding assay. The compound 19 demonstrated very high selectivity for A2AR as compared to standard A2AR antagonist SCH58261. Decrease in A2AR-coupled release of endogenous cAMP in treated HEK293T cells demonstrated in vitro A2AR antagonist potential of the compound 19. Attenuation in haloperidol-induced impairment (catalepsy) in Swiss albino male mice pre-treated with compound 19 is evocative to explore its prospective in therapy of PD. 相似文献
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Sharad Chandra Deepak Ameta Sudarshan Kumar Vijay Sudhanshu Kumar Dwivedi Ram Kirti Saran 《Indian pacing and electrophysiology journal》2013,13(2):84-87
Inferior vena caval thrombosis is an unusual complication of permanent pacemaker implantation. The clinical presentation due to thrombosis depends on the site of thrombus. We have described here a rare case of pacemaker lead associated thrombosis of inferior vena cava, its diagnostic work up and briefly reviewed the existing literature of this uncommon complication. 相似文献
125.
This paper presents an electrochemical immune sensor for label free detection of epidermal growth factor receptor (EGFR) by immobilizing anti-EGFR antibody (Anti-EGFRab) on dithiobissuccinimidyl propionate (DTSP) self-assembled monolayer (SAM) on gold (Au) electrode. Electrochemical studies show that increased surface concentration of redox moieties onto Anti-EGFRab/DTSP immuno-electrode leads to high electron transport and improved sensing performance. The antigen-antibody complex demonstrates a high association constant (5×10(12)L/mol) that results in high affinity of Anti-EGFRab to EGFR, confirming that the DTSP-SAM provides a conducive environment for anti-EGFR immobilization. The electrochemical response of EA/Anti-EGFRab/DTSP/Au electrode as a function of EGFR concentrations exhibits a linear range from 1pg/mL to 100ng/mL, a detection limit of 1pg/mL at a sensitivity of 2.02μAM(-1)at a regression coefficient of 0.99. 相似文献
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Respiratory Viruses Associated Hospitalization among Children Aged <5 Years in Bangladesh: 2010-2014
Nusrat Homaira Stephen P. Luby Kamal Hossain Kariul Islam Makhdum Ahmed Mustafizur Rahman Ziaur Rahman Repon C. Paul Mejbah Uddin Bhuiyan W. Abdullah Brooks Badrul Munir Sohel Kajal Chandra Banik Marc-Alain Widdowson Melisa Willby Mahmudur Rahman Joseph Bresee Katharine-Sturm Ramirez Eduardo Azziz-Baumgartner 《PloS one》2016,11(2)
Background
We combined hospital-based surveillance and health utilization survey data to estimate the incidence of respiratory viral infections associated hospitalization among children aged < 5 years in Bangladesh.Methods
Surveillance physicians collected respiratory specimens from children aged <5 years hospitalized with respiratory illness and residing in the primary hospital catchment areas. We tested respiratory specimens for respiratory syncytial virus, parainfluenza viruses, human metapneumovirus, influenza, adenovirus and rhinoviruses using rRT-PCR. During 2013, we conducted a health utilization survey in the primary catchment areas of the hospitals to determine the proportion of all hospitalizations for respiratory illness among children aged <5 years at the surveillance hospitals during the preceding 12 months. We estimated the respiratory virus-specific incidence of hospitalization by dividing the estimated number of hospitalized children with a laboratory confirmed infection with a respiratory virus by the population aged <5 years of the catchment areas and adjusted for the proportion of children who were hospitalized at the surveillance hospitals.Results
We estimated that the annual incidence per 1000 children (95% CI) of all cause associated respiratory hospitalization was 11.5 (10–12). The incidences per 1000 children (95% CI) per year for respiratory syncytial virus, parainfluenza, adenovirus, human metapneumovirus and influenza infections were 3(2–3), 0.5(0.4–0.8), 0.4 (0.3–0.6), 0.4 (0.3–0.6), and 0.4 (0.3–0.6) respectively. The incidences per 1000 children (95%CI) of rhinovirus-associated infections among hospitalized children were 5 (3–7), 2 (1–3), 1 (0.6–2), and 3 (2–4) in 2010, 2011, 2012 and 2013, respectively.Conclusion
Our data suggest that respiratory viruses are associated with a substantial burden of hospitalization in children aged <5 years in Bangladesh. 相似文献127.
An amperometric lactate biosensor based on lactate dehydrogenase immobilized onto graphene oxide nanoparticles‐modified pencil graphite electrode 下载免费PDF全文
A novel amperometric lactate biosensor was developed based on immobilization of lactate dehydrogenase onto graphene oxide nanoparticles‐decorated pencil graphite electrode. The enzyme electrode was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and cyclic voltammetry at different stages of its construction. The biosensor showed optimum response within 5 s at pH 7.3 (0.1 M sodium phosphate buffer) and 35°C, when operated at 0.7 V. The biosensor exhibited excellent sensitivity (detection limit as low as 0.1 μM), fast response time (5 s), and wider linear range (5–50 mM). Analytical recovery of added lactic acid in serum was between 95.81–97.87% and within‐batch and between‐batch coefficients of variation were 5.04 and 5.40%, respectively. There was a good correlation between serum lactate values obtained by standard colorimetric method and the present biosensor (r = 0.99). The biosensor measured lactate levels in sera of apparently healthy subjects and persons suffering from lactate acidosis and other biological materials (milk, curd, yogurt, beer, white wine, and red wine). The enzyme electrode lost 25% of its initial activity after 60 days of its regular uses, when stored dry at 4°C. 相似文献
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Deriving C4 photosynthetic parameters from combined gas exchange and chlorophyll fluorescence using an Excel tool: theory and practice 下载免费PDF全文
The higher photosynthetic potential of C4 plants has led to extensive research over the past 50 years, including C4‐dominated natural biomes, crops such as maize, or for evaluating the transfer of C4 traits into C3 lineages. Photosynthetic gas exchange can be measured in air or in a 2% Oxygen mixture using readily available commercial gas exchange and modulated PSII fluorescence systems. Interpretation of these data, however, requires an understanding (or the development) of various modelling approaches, which limit the use by non‐specialists. In this paper we present an accessible summary of the theory behind the analysis and derivation of C4 photosynthetic parameters, and provide a freely available Excel Fitting Tool (EFT), making rigorous C4 data analysis accessible to a broader audience. Outputs include those defining C4 photochemical and biochemical efficiency, the rate of photorespiration, bundle sheath conductance to CO2 diffusion and the in vivo biochemical constants for PEP carboxylase. The EFT compares several methodological variants proposed by different investigators, allowing users to choose the level of complexity required to interpret data. We provide a complete analysis of gas exchange data on maize (as a model C4 organism and key global crop) to illustrate the approaches, their analysis and interpretation. © 2015 John Wiley & Sons Ltd 相似文献