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Neha?Singh Avinash?C.?Tripathi Aseem?Tewari Ravi?Kumar Shailendra?K.?SarafEmail author 《Medicinal chemistry research》2015,24(5):1927-1941
A series of new 5-aryliden-2-imino-4-thiazolidinones (5a–e and 6a–e) were synthesized via a three-step reaction and characterized by physicochemical and spectral data. The uniqueness of the derivatives lies in the fact that none of them had an acidic group, like conventional NSAIDS, but exhibited significant in vivo activity in acute inflammation models. In particular, 5-(3-chlorobenzyliden)-2-(pyridin-2-yl-imino)-4-thiazolidinone(5a) and 5-(3-chlorobenzyliden)-2-(5-methylisoxazol-3-yl-imino)-4-thiazolidinone (6a) showed remarkable paw oedema inhibition (67.76 and 74.47 % oedema inhibition, respectively, after 3 h) comparable to that of Ibuprofen (74.56 % oedema inhibition, after 3 h) at half of the dose of the standard drug. Also, compounds 5a (72.86 %) and 6a (80.20 %) were found to possess significant inhibition of albumin denaturation when screened for in vitro anti-inflammatory activity. In addition, these compounds were docked into the known active site of COX-2 protein using Glide XP and QPLD algorithms, and the binding-free energy was calculated using Prime MM/GBSA simulation methods. The combined use of molecular docking and MM/GBSA methods gave a good correlation between the predicted binding-free energy and experimentally determined biological activities. It was also evident from the docking results that 2-methylisoxazolylimino or 2-(pyridin-2-yl-imino substitution and 3-chloro moiety on 5-benzylidin nucleus of these 4-thiazolidinone derivatives can easily occupy the COX-2 binding pocket, considered as the critical interaction for COX-2 inhibition. Moreover, pharmacokinetic properties of all the synthesized compounds were predicted, with good results. Further, the synthesized derivatives showed neither acute toxicity nor symptoms of gastric ulceration, at extended doses, owing to the absence of an acidic group. 相似文献
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Chloride–bromide halogen exchange was realized when a mixture of an alkyl chloride and an alkyl bromide were reacted over a supported molten alkyl phosphonium catalyst. Conversion was found to be near equilibrium in a tubular flow reactor at 150 °C and 1500 GHSV. The catalyst was prepared by impregnation of alumina or silica support and found to be highly stable for relatively long periods of time. A pathway for the catalytic cycle is proposed.Chloride–bromide halogen exchange was realized when a mixture of an alkyl chloride and an alkyl bromide were reacted over a supported molten alkyl phosphonium catalyst. 相似文献
34.
Priti Bijpuria Laxmi Parsa Alexander Schlachterman Asyia Ahmad 《Hospital practice (1995)》2015,43(1):31-35
Background: Gastrointestinal specialists depend on internal medicine (IM) teams to accurately identify acute gastrointestinal bleeding (GIB). We evaluated whether IM residents’ assessment of GIB correlated with the impressions of GI specialists during consultations at an inner-city university teaching hospital. Methods: A questionnaire was distributed to house staff requesting GIB consultations and to the GI fellows performing the consults between August 2011 and April 2012. Residents and fellows were asked to assess GIB, specifically melena, using a stool color card and digital rectal examination (DRE) findings. Fellow DRE findings served as controls for stool color identification. Results: Eighty-seven GI consults were eligible for the study. Residents and fellows completed 81 and 86 questionnaires, respectively. A total of 76 questionnaires were included for analysis. A DRE was performed by medical staff before calling a consult in 65% of cases compared with fellows (97% of cases, P = 0.0001). Residents more frequently labeled stool as melena (42%) in patients as compared with fellows (12%, P = 0.0001). Residents inaccurately identified melenic stools in 22 patients (11 based on stool color and 11 based on DRE findings). Residents were more likely to label a consult as emergent than fellows (13.5% vs 4%, P < 0.05). Conclusion: Residents are less likely to perform DRE during an evaluation for GIB and to accurately identify melena based on stool color or DRE findings. There appears to be a need to educate residents on the appropriate terminology for stool color and the importance of DRE to accurately triage patients with acute GIBs. 相似文献
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Deepanker Tewari Fabio Del Piero Stephen Cieply Willard Feria Helen Acland 《Journal of virological methods》2013
Equine herpesvirus-1 (EHV-1) strains with a single point mutation at the 2254 nucleotide position with a G2254 constitution within the DNA polymerase gene are associated strongly with equine myeloencephalopathies. Infections with non-neuropathogenic EHV-1 strains without the G2254 nucleotide but with an A2254 nucleotide are associated less frequently with equine neurologic disease. A retrospective study utilizing DNA extracted from formalin fixed paraffin embedded tissues was conducted with real time PCR and pyrosequencing, to determine the infecting EHV-1 strains. Infection with EHV-1 A2254 and or G2254 strain was detected with real time PCR, and was confirmed with a rapid pyrosequencing technique. Pyrosequencing was useful in at least 2 cases where real time PCR was equivocal in determining the infecting EHV-1 strain type. The strain with G2254 mutation was detected in 9.4% of 21 studied abortion cases, and in 86.6% of 15 neurologic cases. 相似文献
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Zhanyong Bing Priti Lal Song Lu Amy Ziober John E. Tomaszewski 《Annals of diagnostic pathology》2013,17(1):58-62
Kidney tumors of various types may behave differently and have different prognosis. Because of some overlapping morphological features and immunohistochemical staining pattern, they may pose diagnostic challenge. Therefore, it is necessary to explore additional immunohistochemical stains to help classifying these epithelial neoplasms. Tissue microarrays of 20 cases each of renal cell carcinomas of clear cell, chromophobe, and papillary variants and oncocytoma were constructed and used to test a panel of immunohistochemical markers including carbonic anhydrase IX, galectin-3, cytokeratin 7 (CK7), and α-methylacyl coenzyme a racemase. Carbonic anhydrase IX was highly sensitive for clear cell renal cell carcinoma (90% positivity) and was negative in all other renal epithelial tumors except for 1 chromophobe renal cell carcinoma (chRCC). Expression of galectin-3 was found mostly in renal tumors with oncocytic features, including oncocytomas (100%) and chRCCs (89%). α-Methylacyl coenzyme a racemase was positive in papillary renal cell carcinoma (100%). CK7 was positive in papillary renal cell carcinoma (90%), chRCC (89%), and oncocytoma (90%). Although both chRCC and oncocytoma were positive for CK7, but with a different patterns, CK7 staining in chRCC was diffuse, whereas it was sporadic in oncocytoma. Panel of carbonic anhydrase IX, galectin-3, CK7, and α-methylacyl coenzyme a racemase is sensitive and specific for the differential diagnosis of the renal epithelial tumors. 相似文献
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Jerina Tewari Pravash Ranjan Mishra Sujit Kumar Tripathy 《Indian Journal of Orthopaedics》2015,49(5):549-553