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Itatiana F. Rodart Madalena M. Pares Aline Mendes Camila M. Accardo Joo R. M. Martins Cleidenice B. Silva Fabrício O. Carvalho Jos A. Barreto Mitermayer G. Reis Ivarne L. S. Tersariol Helena B. Nader 《Molecules (Basel, Switzerland)》2021,26(13)
Background: The disease caused by hepatitis C virus (HCV) is asymptomatic, silent, and progressive liver disease. In HCV-infected patients the increase in serum HA is associated with the development of hepatic fibrosis and disease progression. Methods: HCV-RNA detection was performed in all serological samples of blood donors that tested positive using HCV Ultra ELISA. Determination of hyaluronan (HA) was performed in positive HCV samples using ELISA-like fluorometric method. The HA content was compared to HCV viral load, genotype of the virus, liver fibrosis as well as ALT and GGT liver biomarkers. Results: Persistently normal ALT (<40 U/L) and GGT (<50 U/L) serum levels were detected in 75% and 69% of the HCV-Infected blood donors, respectively. Based on ROC analysis, the HA value < 34.2 ng/mL is an optimal cut-off point to exclude HCV viremia (specificity = 91%, NPV = 99%). Applying HA value ≥34.2 ng/mL significant liver fibrosis (≥F2) can be estimated in 46% of the HCV-infected blood donors. HA serum level (≥34.2 ng/mL) associated with a high ALT level (>40 U/mL) can correctly identify HCV infection and probable liver fibrosis (sensitivity = 96% and specificity = 90%) in asymptomatic blood donors. Conclusions: A high level of HA (≥34.2 ng/mL) in association with ALT (≥40 U/L) in serum can provide a good clinical opportunity to detect HCV-infected asymptomatic persons that potentially require a liver biopsy confirmation and antiviral treatment to prevent the development of advanced liver fibrosis or cirrhosis. 相似文献
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225.
Thioetherification of Chloroheteroarenes: A Binuclear Catalyst Promotes Wide Scope and High Functional‐Group Tolerance
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Dr. Mélanie Platon Novi Wijaya Vincent Rampazzi Luchao Cui Dr. Yoann Rousselin Prof. Dr. Mark Saeys Prof. Dr. Jean‐Cyrille Hierso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12584-12594
A constrained binuclear palladium catalyst system affords selective thioetherification of a wide range of functionalized arenethiols with chloroheteroaromatic partners with the highest turnover numbers (TONs) reported to date and tolerates a large variety of reactive functions. The scope of this system includes the coupling of thiophenols with six‐ and five‐membered 2‐chloroheteroarenes (i.e., functionalized pyridine, pyrazine, quinoline, pyrimidine, furane, and thiazole) and 3‐bromoheteroarenes (i.e., pyridine and furane). Electron‐rich congested thiophenols and fluorinated thiophenols are also suitable partners. The coupling of unprotected amino‐2‐chloropyridines with thiophenol and the successful employment of synthetically valuable chlorothiophenols are described with the same catalyst system. DFT studies attribute the high performance of this binuclear palladium catalyst to the decreased stability of thiolate‐containing resting states. Palladium loading was as low as 0.2 mol %, which is important for industrial application and is a step forward in solving catalyst activation/deactivation problems. 相似文献
226.
《Journal of Coordination Chemistry》2012,65(21):3410-3419
Unsymmetrical and symmetrical mononuclear and insoluble polynuclear oxo-vanadium(IV) Schiff-base complexes were prepared and characterized. The complexes [VO(5-x-6-y-Sal)(5-x′-6-y′-Sal)en)] (where x, x′ = H, Br and y, y′ = H, OMe) were obtained in monomeric form while for x or x′ = NO2 polymers were produced. In the case of [VO(5-x-6-y-Sal)(5-x′-6-y′-Sal)pn)] with a six-member N–N chelating ring, oxo-vanadium(IV) complexes were polynuclear. The tetradentate N2O2-Schiff-base ligands are coordinated in the equatorial plane of oxo-vanadium(IV). Electrochemical and spectroscopic data (UV–Vis and IR) suggest importance of coordination geometry and the substiuents on phenyl rings and the bridge group. Electron density of the vanadium center decreases by the electron-withdrawing groups on the ligand while electron density on vanadium increases via σ-donation of phenolic oxygen. 相似文献
227.
V.A. Shelke S.M. Jadhav V.R. Patharkar S.G. Shankarwar A.S. Munde T.K. Chondhekar 《Arabian Journal of Chemistry》2012,5(4):501-507
The solid complexes of La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) with 4-hydroxy-3-(1-{2-(2-hydroxy-benzylidene)-aminophenylimino}-thyl)-6-methy-pyran-2-one (H2L) derived from o-phenylenediamine, 3-acetyl-6-methyl-(2H)pyran,2,4(3H)-dione (dehydroacetic acid or DHA) and salicylic aldehyde have been synthesized and characterized by elemental analysis, conductometry, magnetic susceptibility, UV–visible, FTIR, 1H NMR spectra, X-ray diffraction, and thermal analysis and screened for antimicrobial activity. The FTIR spectral data suggest that the ligand behaves as a dibasic tetradentate ligand with ONNO donar atoms sequence towards central metal ion. From the microanalytical data, the stoichiometry of the complexes has been found to be 1:1 (metal:ligand). The physico-chemical data suggest distorted octahedral geometry for La(III), Ce(III), Pr(III), Nd(III), Sm(III) and Gd(III) complexes. The X-ray diffraction data suggest monoclinic crystal system for La(III) and Ce(III) and orthorhombic crystal system for Pr(III) and Nd(III) complexes. Thermal behaviour (TGA/DTA) of the complexes was studied and kinetic parameters were determined by Horowitz–Metzger and Coats–Redfern methods. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus, Escherichia coli and Bacillus sp. Fungicidal activity against Aspergillus niger, Trichoderma and Fusarium oxysporum. 相似文献
228.
《Journal of Coordination Chemistry》2012,65(4):349-357
Abstract The reaction of platinum(II) halides with stoichiometric amounts of either dimethyl sulfoxide (DMSO) or thiocarbamic ester (L) in acetone yields the complexes cis-[Pt(L)(DMSO)X2], where L α MTC (EtOSCNHMe), ETC (EtOSCNHEt) or TC (EtOSCNH2) and X α Cl or Br. The compounds have been isolated and characterized by elemental analysis and by infrared and nmr (1H and 13C) spectroscopy. Either dimethyl sulfoxide or thiocarbamic ester coordinate through the sulphur atom. In the MTC and ETC adducts the planar ligand molecule is present in the isomeric form bearing the N-alkyl group in an anti position with respect to the thiocarbonyl group. 相似文献
229.
Francisco O.N. da Silva Elis C.C. Gomes Thiago dos S. Francisco Alda K.M. Holanda Izaura C.N. Digenes Eduardo H.S. de Sousa Luiz G.F. Lopes Elisane Longhinotti 《Polyhedron》2010,29(18):251-3354
The reaction of [Ru(bpy)2Cl2] and Na2[Fe(CN)4(dmso)2] complexes with isonicotinic acid immobilized on silica spheres (Si-ATPS-ISN) followed by a NO bubbling produced Si-ATPS-ISN-[Ru(bpy)2(NO)] (system I) and Si-ATPS-ISN-[Fe(CN)4(NO)] (system II). The characterization of these systems was carried out by UV–Vis, FTIR spectroscopy and electrochemical techniques. As judged by the FTIR data, the nitric oxide ligand has an NO+ character in both systems (ν(NO+): 1938 cm−1). The NO release, which was monitored by means of FTIR, electrochemistry, and NO sensor electrode, was observed for both systems upon white light irradiation and chemical reduction by cysteine. These results indicated that the system (II) presents a higher potential for controlled NO release. The characterization (FTIR and UV–Vis) of the systems after the NO release suggested the formation of the aqua systems ATPS-ISN-[Ru(bpy)2(OH2)] and ATPS-ISN-[Ru(bpy)2(OH2)]. 相似文献
230.
Shallow donors in silicon related to nitrogen–oxygen complexes have been investigated by piezospectroscopy of their hydrogenic transitions in the far infrared. Complete stress dependences up to 0.25 GPa were obtained for the 1s→2p0 and 1s→2p± transitions of the most prominent members of the (N, O)-family, N–O-3 and N–O-5. Very unusual for shallow donors in silicon, the symmetry of the ground state wave function is T2-like. The lifting of orientational degeneracy for stress in the 〈1 0 0〉, 〈1 1 1〉, and 〈1 1 0〉 directions is compatible with a C2v defect symmetry. Data from the other species of the (N, O)-family are indicative for the same symmetry. The microscopic structure of these centers, in part contradictory to present theoretical models, is discussed. 相似文献