The present study was aimed to evaluate the effect of licofelone, a dual inhibitor of cycloxygenase1/2-5-lipoxygenase against indomethacin-induced gastric damage in rats and mice in order to assess the role of leukotrienes if any, in non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastrointestinal inflammation. Acute pretreatment with licofelone reversed the indomethacin-induced gastric ulceration, neutrophil adhesion in mesentery venules, neutrophil count in blood, lipid peroxides and vascularity in the stomachs of mice and rats. Further, chronic pretreatment of licofelone also prevented indomethacin-induced gastric morphological changes and cellular infiltration in mesentery venules. Moreover, acute administration of indomethacin elevated leukotriene B4 levels in gastric mucosa, which was reversed by pretreatment with licofelone The results suggest that licofelone offered gastroprotection against NSAIDs-induced gastropathy through its effect on leukotrienes and by inhibiting extravasation of neutrophils.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Ritika Sachdeva, Prabhjot Kaur, V. P. Singh, G. S. S. Saini; Density functional theory studies of etoricoxib. AIP Conf. Proc. 6 May 2016; 1728 (1): 020530. https://doi.org/10.1063/1.4946581 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioAIP Conference Proceedings Search Advanced Search |Citation Search
The synthesis of a variety of aromatic amines carrying an ortho-alkyltelluro group is described. The new antioxidants quenched lipidperoxyl radicals much more efficiently than α-tocopherol and were regenerable by aqueous-phase N-acetylcysteine in a two-phase peroxidation system. The inhibition time for diaryl amine 9 b was four-fold longer than recorded with α-tocopherol. Thiol consumption in the aqueous phase was found to correlate inversely to the inhibition time and the availability of thiol is the limiting factor for the duration of antioxidant protection. The proposed mechanism for quenching of peroxyl radicals involves O-atom transfer from peroxyl to Te followed by H-atom transfer from amine to alkoxyl radical in a solvent cage.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
<abstract><title><italic>Abstract.</italic></title> The flow duration curve (FDC) is employed for addressing a multitude of problems in water resources engineering, such as prediction of the distribution of future flows, forecasting of future recurrence frequencies, comparison of watersheds, construction of load duration curves, and determination of low flow thresholds. Usually, the FDC is constructed empirically for a given set of flow data, and the FDC so constructed is found to vary from one year to another and from one gauging station to another within the same watershed. This article attempts to analytically derive the FDC by maximizing the Tsallis entropy based on the knowledge that the mean discharge is known, thus obviating the need for any fitting. The mean discharge is found to be strongly related to the drainage area. The Tsallis entropy-based FDC is tested using field data and is found to be in agreement with the observed curve. The entropy method permits a probabilistic characterization of the FDC and hence a quantitative assessment of its uncertainty. With this method, the flow duration curve can also be forecasted for different recurrence intervals. The entropy is found to monotonically increase with the increase in time interval, indicating that the flow system becomes more complex but the degree of complexity decreases with increasing time interval after a certain time, eventually reaching a constant value, reflecting a reduced influence of land use change and other human influences on the flow regime.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ABSTRACT The present study is aimed at investigating the hydroperoxide scavenging activity and chemical mechanisms of the selected organoselenium compounds (diphenyl selenoxide, diphenyl selenide, and diphenyl diselenide) in reaction with model lipid hydroperoxide—cumene hydroperoxide. The reaction products were identified using GC–MS, HPLC, FT‐IR, and 1 H NMR techniques. The yield of free radicals was determined by the spin‐trap ESR study and inhibitors' method and evaluated to be less than 10 −5 within the accuracy of the used methods. It was established that the main products of the conversion of cumene hydroperoxide in the reaction with selected organoselenium compounds are dimethyl phenyl carbinol, acetophenone, and α ‐methylstyrene. The chemical mechanism of the antihydroperoxide action of selenium compounds has been suggested. The key lies in their ability to engage in multiple chemical pathways simultaneously. Notably, two‐electron transfer reactions take center stage, effectively neutralizing the hydroperoxides without generating strong reactive oxygen species—free radicals.
Based on the traditional 77 Se NMR spectroscopy investigation, a catalytic cycle for the formation of N -thiophenyl ebselenamine 12 involving diselenide 9 , selenenyl sulfide 10 and ebselenamine 7a was reported by the reaction of azo-bis-ebselen 8 with PhSH and H 2 O 2 . The signals detected in the 77 Se NMR spectrum corresponding to 7a , 10 and 12 were directly isolated from the NMR mixture. Mechanistic investigation for the formation of N -thiophenyl ebselenamine 12 was confirmed from an independent reaction of diselenide 9 and PhSSPh in the presence of H 2 O 2 . This was further supported by another diselenide 19 containing p -tolyl group with equimolar amount of H 2 O 2 and PhSH in an independent experiment followed by the 77 Se NMR spectroscopy, yielding similar observations. These results, which illustrated diselenide has been observed as the main precursor in the formation of all intermediates. The new novel selenium antioxidants quenched lipidperoxyl radicals much more efficiently than α-tocopherol and were regenerable by the aqueous ascorbic acid in a two-phase (chlorobenzene/water) azo-initiated peroxidation system. The notable benefit of the organoselenium biology, the novel ebselenamine analogues and their corresponding selenenyl sulfides were found to mimic the activity of the glutathione peroxidase enzymes better than ebselen in the coupled reductase assay.
Tramadol, a weak opioid agonist with effects on adrenergic and serotonergic neurotransmission, is used to treat conditions varying from postoperative to chronic malignant pain. Additionally, selective serotonin reuptake inhibitors (SSRIs) are used as adjuvants or prophylactics for the associated residual pain component. The present work evaluates, by isobolographic analysis, the interaction between a combination of racemic (±) tramadol, an opioid agonist, and fluoxetine, an SSRI, using a chemical analgesiometric test (abdominal writhing). Intraperitoneal administration of both tramadol (0.5–20 mg/kg) and fluoxetine (5–40 mg/kg) produced dose‐dependent antinociception. Co‐administration of fixed ratios of ED 50 fractions of fluoxetine and tramadol resulted in an additive effect. However, the least dose of fluoxetine (2.1 mg/kg) and tramadol (0.21 mg/kg) used in fixed ratios for antinociceptive effect individually showed antidepressant activity in a modified Porsolt forced swim test. The interaction studies in the writhing test suggested that such combinations might be devoid of any additional advantage over the individual drug regimen in acute cases of pain with co‐morbidity of depression. Further, the nature of interaction for such combinations in chronic pain models needs further assessment. Drug Dev. Res. 61:79‐85, 2004. © 2004 Wiley‐Liss, Inc.
Novel azo-bis-ebselen compounds 7 were prepared by reduction of 7-nitro-2-aryl-1,2-benzisoselenazol-3(2H)-ones 3 and 6 with sodium benzenetellurolate, NaTeC6H5, and by reaction of 2-bromo-3-nitrobenzamides with Na2Se2. The X-ray structure of 7b showed that the molecule, due to strong intramolecular secondary Se···N interactions, is completely planar. Azo-compounds 7 upon further reaction with NaTeC6H5 were reductively cleaved to provide 2 equiv of the corresponding aromatic amine. The weak Se-N bond was not stable enough to survive the reaction conditions, and diselenides 8 were isolated after workup. Whereas azo-bis-ebselens 7 were poor mimics of the glutathione peroxidase (GPx)-enzymes, nitroebselens 3, 6, and 11b and diselenides 8 were 3-6-fold more active than ebselen. Based on 77Se NMR spectroscopy, a catalytic cycle for diselenide 8b, involving aminoebselen 14, was proposed. As assessed by chemiluminescence measurements, the good GPx-mimics could reduce production of reactive oxygen species (ROS) in stimulated human mononuclear cells more efficiently than Trolox. No toxic effects of the compounds were seen in MC3T3-cells at 25 μM.
Article SULFUR BONDED UNSYMMETRICAL BOROLE COMPLEXES: SYNTHETIC, SPECTROSCOPIC AND BIOCIDAL ASPECTS was published on April 1, 1998 in the journal Main Group Metal Chemistry (volume 21, issue 4).
No abstract is provided for this article.
