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851.
Bassam Felipe Mogharbel Marco Andr Cardoso Ana Carolina Irioda Priscila Elias Ferreira Stricker Robson Camilotti Slompo Julia Maurer Appel Nathalia Barth de Oliveira Maiara Carolina Perussolo Claudia Sayuri Saaki Nadia Nascimento da Rosa Dilcele Silva Moreira Dziedzic Christophe Travelet Sami Halila Redouane Borsali Katherine Athayde Teixeira de Carvalho 《Molecules (Basel, Switzerland)》2022,27(9)
Background: Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the gold-standard drug available for treating PD. Curcumin has many pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, and antitumor properties. Copolymers composed of Poly (ethylene oxide) (PEO) and biodegradable polyesters such as Poly (ε-caprolactone) (PCL) can self-assemble into nanoparticles (NPs). This study describes the development of NH2–PEO–PCL diblock copolymer positively charged and modified by adding glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA curcumin that would be able to pass the blood–brain barrier. Methods: The NH2–PEO–PCL NPs suspensions were prepared by using a nanoprecipitation and solvent displacement method and coated with GSH. NPs were submitted to characterization assays. In order to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NPs to observe cytotoxicity. Results: NPs have successfully loaded L-DOPA and curcumin and were stable after freeze-drying, indicating advancing into in vitro toxicity testing. Vero and PC12 cells that were treated up to 72 h with various concentrations of L-DOPA and curcumin-loaded NP maintained high viability percentage, indicating that the NPs are biocompatible. Conclusions: NPs consisting of NH2–PEO–PCL were characterized as potential formulations for brain delivery of L-DOPA and curcumin. The results also indicate that the developed biodegradable nanomicelles that were blood compatible presented low cytotoxicity. 相似文献
852.
Flvia A. R. dos Santos Jadriane A. Xavier Felipe C. da Silva J. P. Jose Merlin Marília O. F. Goulart H. P. Vasantha Rupasinghe 《Molecules (Basel, Switzerland)》2022,27(13)
The objective of this work was to investigate the antidiabetic, antiglycation, and antioxidant potentials of ethanolic extract of seeds of Brazilian Passiflora edulis fruits (PESE), a major by-product of the juice industry, and piceatannol (PIC), one of the main phytochemicals of PESE. PESE, PIC, and acarbose (ACB) exhibited IC50 for alpha-amylase, 32.1 ± 2.7, 85.4 ± 0.7, and 0.4 ± 0.1 µg/mL, respectively, and IC50 for alpha-glucosidase, 76.2 ± 1.9, 20.4 ± 7.6, and 252 ± 4.5 µg/mL, respectively. The IC50 of PESE, PIC, and sitagliptin (STG) for dipeptidyl-peptidase-4 (DPP-4) was 71.1 ± 2.6, 1137 ± 120, and 0.005 ± 0.001 µg/mL, respectively. PESE and PIC inhibited the formation of advanced glycation end-products (AGE) with IC50 of 366 ± 1.9 and 360 ± 9.1 µg/mL for the initial stage and 51.5 ± 1.4 and 67.4 ± 4.6 µg/mL for the intermediate stage of glycation, respectively. Additionally, PESE and PIC inhibited the formation of β-amyloid fibrils in vitro up to 100%. IC50 values for 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging activity of PESE and PIC were 20.4 ± 2.1, and 6.3 ± 1.3 µg/mL, respectively. IC50 values for scavenging hypochlorous acid (HOCl) were similar in PESE, PIC, and quercetin (QCT) with values of 1.7 ± 0.3, 1.2 ± 0.5, and 1.9 ± 0.3 µg/mL, respectively. PESE had no cytotoxicity to the human normal bronchial epithelial (BEAS-2B), and alpha mouse liver (AML-12) cells up to 100 and 50 µg/mL, respectively. However, 10 µg/mL of the extract was cytotoxic to non-malignant breast epithelial cells (MCF-10A). PESE and PIC were found to be capable of protecting cultured human cells from the oxidative stress caused by the carcinogen NNKOAc at 100 µM. The in vitro evidence of the inhibition of alpha-amylase, alpha-glucosidase, and DPP-4 enzymes as well as antioxidant and antiglycation activities, warrants further investigation of the antidiabetic potential of P. edulis seeds and PIC. 相似文献
853.
Sarahi Pacheco-Espinoza Alejandro I. Cuesta-Balderas Jorge Vázquez-Lujano Abril Rosiles-Aguilera María A. Hernández-Pérez Felipe Cervantes-Sodi Fei Chen Qiang Shen Rong Tu Jorge R. Vargas-García Lian-Meng Zhang 《Particle & Particle Systems Characterization》2023,40(4):2200167
The development of new strategies for synthesizing 1D cerium oxide (CeO2) hollow nanostructures has attracted much attention in recent years due to the importance of their superior properties and highly anisotropic geometry. This study reports an unpublished route of fabricating novel multiwalled CeO2-δ nanotubes (CeO2-δ NTs) in which the entire volume of functionalized multiwalled carbon nanotubes (f-MWCNTs) is converted into the CeO2-δ pseudomorph through oxidation and dehydration topotactic reactions. The stable CeO2-δ (111) planes are topotactically grown on the curved C (002) planes, preferentially exposed along the nanotube axis. In their initial condition, the novel nanotubes consist of Ce oxyhydroxide (CeO2-x(OH)x) with residual carbon. When heating the air up to 500 °C, CeO2-x(OH)x transforms gradually by dehydration into CeO2-δ, while the residual carbon is oxidized. Despite compositional changes, nanotubes maintain their multiwalled structural integrity up to ≈550 °C. The CeO2-δ NTs exhibit an unusually high presence of Ce3+ ions and surface O vacancies, contributing to a low direct band gap ranging from 2.67 to 2.32 eV compared to their NPs counterparts (3.2 eV). 相似文献
854.
José Felipe dos Santos Jonatas de Oliveira S. Silva José Fernando Macedo José Carlos S. Júnior Wandson S. Almeida Eliana Midori Sussuchi 《Electroanalysis》2023,35(9):e202200563
Estrone (E1) is associated with various health and environmental issues, necessitating the development of analytical methods for monitoring E1 in different matrices. In this context, the present study reports the development of a graphene quantum dot-based electrode (GQD/E) to detect estrone in water and urine samples. Voltammetric measurements under optimized conditions demonstrated the feasibility of using GQD/E to detect estrone at trace levels in aqueous samples. Two linear dynamic ranges were obtained at concentrations from 0.05 to 10.00 μmol L−1, with limit of detection (LOD) and quantification (LOQ) of 28.0 and 96.0 nmol L−1, respectively. Furthermore, the LOD value obtained in this study is one of the lowest ever reported in the literature for the electrochemical determination of E1. The method response showed no significant variation in the current intensity of E1 in the presence of the 16 interferents. The recovery values obtained by using GQD/E to quantify estrone in fortified samples of seawater, tap water, wastewater and synthetic urine ranged from 95.9 to 108.1 %, indicating that the method presents highly sensitive for detecting estrone in aqueous matrices. 相似文献
855.
Anna Broto-Ribas Sara Ruiz-Relaño Dr. Jorge Albalad Yunhui Yang Dr. Felipe Gándara Dr. Judith Juanhuix Dr. Inhar Imaz Prof. Dr. Daniel Maspoch 《Angewandte Chemie (International ed. in English)》2023,62(48):e202310354
Clip-off Chemistry is a synthetic strategy that our group previously developed to obtain new molecules and materials through selective cleavage of bonds. Herein, we report recent work to expand Clip-off Chemistry by introducing into it a retrosynthetic analysis step that, based on virtual extension of the products through cleavable bonds, enables one to define the required precursor materials. As proof-of-concept, we have validated our new approach by synthesising and characterising four aldehyde-functionalised Rh(II)-based complexes: a homoleptic cluster; a cis-disubstituted paddlewheel cluster; a macrocycle; and a crown. 相似文献
856.
Elgueta Elizabeth Becerra Yerko Martínez Ana Pereira Miguel Carrillo-Varela Isabel Sanhueza Felipe Nuñez Dariela Rivas Bernabé L. 《高分子科学》2023,41(6):874-886
Chinese Journal of Polymer Science - The adsorption capacity of hydrogels derived from modified xylan hemicellulose has been tested in order to develop new bio-based adsorbent materials useful for... 相似文献
857.
Airton Natanael Coelho Dias Carlos Alberto Tello Saenz Carlos Jos Leopoldo Constantino Cleber Jos Soares Felipe Ponciano Novaes Ana Maria Osrio Araya Balan 《Journal of Raman spectroscopy : JRS》2009,40(1):101-106
The zircon mineral is widely studied in geochronology. In the case of the fission track method (FTM), the age is determined by the density of fission tracks at the zircon surface, which can be observed with an optical microscope after an appropriate chemical treatment (etching). The etching must be isotropic at the zircon grain surface to be used in the FTM, which leads those zircon grains whose etching is anisotropic to be discarded. The only reason for this discarding is the nonuniform morphology of the surface grain seen by optical microscopy, that is, no further physicochemical analysis is performed. In this work, combining micro‐Raman and scanning electron microscopy (SEM) to study the etching anisotropy, it was shown that zircon grains that present at least one area at the surface where the density of fission track is uniform can be used in the FTM. The micro‐Raman showed characteristic spectra of the standard zircon sample either from the areas where there are tracks or from where there are not. The only difference found was in the Raman bandwidths, which were broader for the areas with higher density of fission tracks. This suggests simply a decrease in the relative percentage of the crystalline/amorphous phases at these areas. The SEM/energy dispersive spectrometry (EDX) showed that there were no significant differences in the principal chemical composition at the areas with and without fission tracks. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献