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Theodoro T. R. Moura J. O. V. Dias J. R. Carpegiani J. A. Godoy W. M. Aguiar L. G. 《Kinetics and Catalysis》2021,62(1):188-195
Kinetics and Catalysis - The production of sulfonated resins is of great interest to be applied in different industrial processes such as esterification, etherification, biodiesel production and... 相似文献
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John D. Krutty Andrew D. Dias Junsu Yun William L. Murphy Padma Gopalan 《Macromolecular bioscience》2019,19(2)
Mesenchymal stem cells (MSC), also called marrow stromal cells, are adult cells that have attracted interest for their potential uses in therapeutic applications. There is a pressing need for scalable culture systems due to the large number of cells needed for clinical treatments. Here, a tailorable thin polymer coating—poly(poly(ethylene glycol) methyl ether methacrylate‐ran‐vinyl dimethyl azlactone‐ran‐glycidyl methacrylate) [P(PEGMEMA‐r‐VDM‐r‐GMA); PVG]—to the surface of commercially available polystyrene and glass microcarriers to create chemically defined surfaces for large‐scale cell expansion is applied. These chemically defined microcarriers create a reproducible surface that does not rely on the adsorption of xenogenic serum proteins to mediate cell adhesion. Specifically, this coating method anchors PVG copolymer through ring opening nucleophilic attack by amine residues on poly‐l ‐lysine that is pre‐adsorbed to the surface of microcarriers. Importantly, this anchoring reaction preserves the monomer VDM reactivity for subsequent functionalization with an integrin‐specific Arg‐Gly‐Asp peptide to enable cell adhesion and expansion via a one‐step reaction in aqueous media. MSCs cultured on PVG‐coated microcarriers achieve sixfold expansion—similar to the expansion achieved on PS microcarriers—and retain their ability to differentiate after harvesting. 相似文献
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Rafael Dias do Espírito Santo Rosineide Costa Simas Alviclér Magalhães Vanessa Gonçalves dos Santos Thais Regiani Ana Cristina Isler Natiza Graziele Martins Marcos Nogueira Eberlin Eduardo René Pérez González 《Journal of Physical Organic Chemistry》2013,26(4):315-321
Molecules containing the guanidinic nuclei possess several pharmacological applications, and knowing the preferred isomers of a potential drug is important to understand the way it operates pharmacologically. Benzoylguanidines were synthesized in satisfactory to good yields and characterized by NMR, Electrospray Ionization Mass Spectrometry (ESI‐MS) and Fourrier Transform InfraRed Spectroscopy techniques (FTIR). E/Z isomerism of the guanidines was studied and confirmed by NMR analysis in solution (1H‐13C Heteronuclear Single Quantum Coherence (HSQC) and Heteronuclear Multiple‐Bond Correlation (HMBC), 1H‐15N HMBC, 1H‐1H Correlation Spectroscopy (COSY) and Nuclear Overhauser Effect Spectroscopy (NOESY) experiments) at low temperatures. Compounds with p‐Cl and p‐Br aniline moiety exist mainly as Z isomer with a small proportion of E isomer, whereas compounds with p‐NO2 moiety showed a decrease in proportion of isomer Z. The results are important for the application of these molecules as enzymatic inhibitors. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Ribeiro Sabrina Dias Meneguin Andria Bagliotti Barud Hernane da Silva Silva Jhonatan Miguel Oliveira Rafael L. Asuno Rosana Maria Nascimento de Tormin Thiago Faria Muoz Rodrigo Alejandro Abarza Filho Guimes Rodrigues Ribeiro Clovis Augusto 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7265-7275
Journal of Thermal Analysis and Calorimetry - Cellophane film production generates cellulosic residues from scraps, edges, and low-quality films. In this work, cellophane was used as a raw material... 相似文献
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Dr. Jagadeesh Yerri Dr. José Dias Dr. Mallikajurna Reddy Nimmakayala Franck Razafindrainibe Charlotte Courageux Anne-Julie Gastellier Johanne Jegoux Dr. Caroline Coisne Dr. Christophe Landry Dr. Fabien Gosselet Johan Hachani Dr. Jean-François Goossens Prof. Marie-Pierre Dehouck Dr. Florian Nachon Dr. Rachid Baati 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(65):15035-15044
Novel 6-alkyl- and 6-alkenyl-3-fluoro-2-pyridinaldoximes have been synthesised by using a mild and efficient chemoselective hydrogenation of 6-alkynyl-3-fluoro-2-pyridinaldoxime scaffolds, without altering the reducible, unprotected, sensitive oxime functionality and the C−F bond. These novel 6-alkyl-3-fluoro-2-pyridinaldoximes may find medicinal application as antidotes to organophosphate poisoning. Indeed, one low-molecular-weight compound exhibited increased affinity for sarin-inhibited acetylcholinesterase (hAChE) and greater reactivation efficiency or resurrection for sarin-inhibited hAChE, compared with those of 2-pyridinaldoxime (2-PAM) and 1-({[4-(aminocarbonyl)pyridinio]methoxy}methyl)-2-[(hydroxyimino)methyl]pyridinium chloride (HI-6), two pyridinium salts currently used as antidote by several countries. In addition, the uncharged 3-fluorinated bifunctional hybrid showed increased in vitro blood–brain barrier permeability compared with those of 2-PAM, HI-6 and obidoxime. These promising features of novel low-molecular-weight alkylfluoropyridinaldoxime open up a new era for the design, synthesis and discovery of central non-quaternary broad spectrum reactivators for organophosphate-inhibited cholinesterases. 相似文献
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J.C.S. Rocha B.V. Costa P.Z. Coura S.A. Leonel R.A. Dias 《Journal of magnetism and magnetic materials》2012
In this work we report a numerical Monte Carlo study of the behavior of a magnetic nano-disk put over an antiferromagnetic substrate. Three approaches were considered for describe the substrate: (1) A stacked antiferromagnetic configuration, (2) an Ising like arrangement and (3) Heisenberg like spins. For the Heisenberg case we still have considered an easy-plane and an easy-axis symmetry of the substrate. The hysteresis loop for the nano-disk is obtained by considering the three cases. The signature of the vortex in the nano-disk appears as small jumps in the hysteresis curve. Exchange bias effects are observed since the substrate has an easy axis symmetry. 相似文献
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