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91.
Joana Gonalves ngelo Luís Eugenia Gallardo Ana Paula Duarte 《Molecules (Basel, Switzerland)》2022,27(18)
Ayahuasca is an Amazonian drink, which contains β-carboline alkaloids and N,N-dimethyltryptamine. The aim of this study was to evaluate the healing potential of decoctions of a commercial mixture, four individual plants and four mixtures of two plants used in the ayahuasca preparation. Thus, the cytotoxic potential of the samples was evaluated and a wound-healing assay was performed with a NHDF cell line. Subsequently, a parallel artificial membrane permeability assay was also performed, to verify if any psychoactive compound could be absorbed by skin fibroblasts. The integrity and permeability of the cell layer were also evaluated, using the transepithelial electrical resistance assay and Lucifer yellow permeability assay, respectively. The compounds absorbed by the cell layer were quantified by high-performance liquid chromatography coupled to a diode array detector. The results showed that only one sample showed cytotoxicity and all the others promoted the migration of skin fibroblasts. Additionally, it was also verified that β-carbolynic alkaloids and N,N-dimethyltriptamine were not absorbed by the cell layer, and in general, did not interfere with its permeability and integrity. To the best of our knowledge, this is the first study where ayahuasca’s wound-healing potential was evaluated. 相似文献
92.
Graphene Oxide Nanosheets Modified with Single‐Domain Antibodies for Rapid and Efficient Capture of Cells 下载免费PDF全文
Dr. Christopher S. Theile Neelkanth M. Bardhan Dr. Priyank V. Kumar Joao N. Duarte Dr. Takeshi Maruyama Ali Rashidfarrokh Dr. Angela M. Belcher Dr. Hidde L. Ploegh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17178-17183
Peripheral blood can provide valuable information on an individual’s immune status. Cell‐based assays typically target leukocytes and their products. Characterization of leukocytes from whole blood requires their separation from the far more numerous red blood cells. 1 Current methods to classify leukocytes, such as recovery on antibody‐coated beads or fluorescence‐activated cell sorting require long sample preparation times and relatively large sample volumes. 2 A simple method that enables the characterization of cells from a small peripheral whole blood sample could overcome limitations of current analytical techniques. We describe the development of a simple graphene oxide surface coated with single‐domain antibody fragments. This format allows quick and efficient capture of distinct WBC subpopulations from small samples (~30 μL) of whole blood in a geometry that does not require any specialized equipment such as cell sorters or microfluidic devices. 相似文献
93.
Quaternary Stereogenic Centers through Enantioselective Heck Arylation of Acyclic Olefins with Aryldiazonium Salts: Application in a Concise Synthesis of (R)‐Verapamil 下载免费PDF全文
Dr. Caio C. Oliveira Prof. Dr. Andreas Pfaltz Prof. Dr. Carlos Roque Duarte Correia 《Angewandte Chemie (International ed. in English)》2015,54(47):14036-14039
We describe herein a highly regio‐ and enantioselective Pd‐catalyzed Heck arylation of unactivated trisubstituted acyclic olefins to provide all‐carbon quaternary stereogenic centers. Chiral N,N ligands of the pyrimidine‐ and pyrazino‐oxazoline class were developed for that purpose, providing the desired products in good to high yields with enantiomeric ratios up to >99:1. Both linear and branched substituents on the olefins were well‐tolerated. The potential of this new method is demonstrated by the straightforward synthesis of several O‐methyl lactols and lactones containing quaternary stereocenters, together with a concise enantioselective total synthesis of the calcium channel blocker verapamil. 相似文献
94.
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96.
Ivana Lula Maria F. Gomes Dorila Piló-Veloso Antonio L.O. de Noronha Hélio A. Duarte Robson A.S. Santos Rubén D. Sinisterra 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(3-4):293-302
In the present work, inclusion complexes of spironolactone (SP) with β-cyclodextrin (β-CD) in solid phase and aqueous solution were studied by solubility methods, NMR spectroscopy and thermal analysis. The results
showed different kinds of complexations when freeze-drying and kneading methods were used. The freeze-drying product (1:1,
SP:β-CD) showed lower degree of complexation and stability than the (1:2, SP:β-CD) compound obtained by kneading method. The spironolactone molecule was also studied by NMR spectroscopy at 400 MHz. The
chemical shifts of all spironolactone atoms and their inclusion compounds were assigned. Extensive use of 1D and 2D NMR techniques,
including ROESY experiment, allowed verifying the position of the spironolactone molecule inside the cyclodextrin cavity in
both situations. In addition, DFTB-SCC quantum mechanical calculations of the inclusion compounds were performed. The predicted
structural properties are in good agreement with ROESY NMR results. 相似文献
97.
An analytical method, based on separation with gas chromatography (GC) and detection with optical fiber (OF), was used for the separation, detection and quantification of benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene. The use of OF as a detector is based on the variations of the reflected optical power detected when the aromatic compounds eluted from the GC column are sorbed in a thin polymeric film on a single-mode OF. General figures of merit, such as the analytical time, analytical error and analytical performance of GC-OF were similar to those of the classical analytical methods, such as a gas chromatography-flame ionization detector (GC-FID). However, the developed GC-OF method constitutes a much less expensive alternative for the speciation of aromatic hydrocarbons compounds, with high accuracy, and being most suitable for actual monitoring work on confined environments. 相似文献
98.
We use the system-plus-reservoir approach to study the dynamics of a system composed of two independent Brownian particles. We present an extension of the well-known model of a bath of oscillators which is capable of inducing an effective coupling between the two particles depending on the choice made for the spectral function of the bath oscillators. The coupling is nonlinear in the variables of interest, and an exponential dependence on these variables is imposed in order to guarantee the translational invariance of the model if the two particles are not subject to any external potential. The effective equations of motion for the particles are obtained by the Laplace transform method, and, besides recovering all the local dynamical properties for each particle, we end up with an effective interaction potential between them. We explicitly analyze one of its possible forms. 相似文献
99.
A J M Barros J C O Santos S Prasad V D Leite A G Souza L E B Soledade M S B Duarte V D dos Santos 《Journal of Thermal Analysis and Calorimetry》2006,83(2):291-295
The conventional treatments
of effluents containing heavy metals produce significant quantities of byproducts
with recalcitrant characteristics, making necessary looking after alternative
techniques in order to avoid the production of new contaminated residues.
Sorption process of chromium and zinc in vertical columns loaded with sewage
sludge and organic solid waste has been studied in this work. The data from
the TG curves of the two sorbents presented significant differences when they
were submitted to the metal uptake, being noticed the displacement of the
thermal events towards lower temperatures for both types of sorbents studied.
As it was expected, for both sorbents, an increase in the mass of samples
has been observed at the completion of the thermal tests upon metal uptake.
Therefore, these facts demonstrate that during the biosorption process a physico-chemical
interaction took place between sorbents and metals, as it was evidenced by
the more than 100 K increase in the decomposition temperatures as well as
the variation of the ΔH values of the
samples. 相似文献
100.
Teixeira FC Ramos H Antunes IF Curto MJ Duarte MT Bento I 《Molecules (Basel, Switzerland)》2006,11(11):867-889
A series of indazoles substituted at the N-1 and N-2 positions with ester-containing side chains -(CH2)(n)CO2R of different lengths (n = 0-6, 9, 10) are described.Nucleophilic substitution reactions on halo esters (X(CH2)(n)CO2R) by 1H-indazole inalkaline solution lead to mixtures of N-1 and N-2 isomers, in which the N-1 isomer predominates. Basic hydrolysis of the ester derivatives allowed the synthesis of the corresponding indazole carboxylic acids. All compounds were fully characterised by multinuclear NMR and IR spectroscopies, MS spectrometry and elemental analysis; the NMR spectroscopic data were used for structural assignment of the N-1 and N-2 isomers.The molecular structure of indazol-2-yl-acetic acid (5b) was determined by X-ray diffraction, which shows a supramolecular architecture involving O2-H...N1 intermolecular hydrogen bonds. 相似文献