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1.
Nanomaterials (Basel) ; 14(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38921883

RESUMEN

Fungal growth on construction materials in tropical climates can degrade aesthetics and manifestations on modern and historical sick buildings, affecting the health of their inhabitants. This study synthesized ZnO nanoparticles with enhanced antifungal properties using a precipitation method. Different concentrations (25%, 50%, and 100%) of Eichhornia crassipes aqueous extract were used with Zn(NO3)2·6H2O as the precursor to evaluate their spectroscopic, morphological, textural, and antifungal properties. X-ray diffraction confirmed the hexagonal wurtzite phase of ZnO with crystallite sizes up to 20 nm. Fourier-transform infrared spectroscopy identified absorption bands at 426, 503, and 567 cm-1 for ZnO-100, ZnO-50, and ZnO-25, respectively. Nitrogen physisorption indicated a type II isotherm with macropores and a fractal dimension coefficient near 2 across all concentrations. Polydispersity index analysis showed that ZnO-50 had a higher PDI, indicating a broader size distribution, while ZnO-25 and ZnO-100 exhibited lower PDI values, reflecting uniform and monodisperse particle sizes. FESEM observations revealed semi-spherical ZnO morphologies prone to agglomeration, particularly in ZnO-25. Antifungal tests highlighted ZnO-25 as the most effective, especially against Phoma sp. with an MFC/MIC ratio of 78 µg/mL. Poisoned plate assays demonstrated over 50% inhibition at 312 µg/mL for all tested fungi, outperforming commercial antifungals. The results indicate that ZnO NPs synthesized using E. crassipes extract effectively inhibit fungal growth on construction materials. This procedure offers a practical approach to improving the durability of building aesthetics and may contribute to reducing the health risks associated with exposure to fungal compounds.

2.
Polymers (Basel) ; 13(12)2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34208138

RESUMEN

In this work, a pH-responsive drug-carrier based on chitosan-silica nanospheres was developed as a carrier for Albendazole (ABZ), a poorly water-soluble anthelmintic drug. Spherical silica nanoparticles were obtained by Stöber method and further etched to obtain mesoporous particles with sizes ranging from 350 to 400 nm. The specific BET area of nanoparticles increased from 15 m2/g to 150 m2/g for etched silica, which also exhibited a uniform pore size distribution. X-ray powder diffraction showed the presence of amorphous phase of silica and a low-intensity peak attributed to ABZ for the drug-loaded nanoparticles. A uniform layer of chitosan was obtained ranging from 10 to 15 nm in thickness due to the small concentration of chitosan used (0.45 mg of chitosan/mg of SiO2). The in vitro evaluation of hybrid nanoparticles was performed using four cervical cancer cell lines CaSki, HeLa, SiHa and C33A, showing a significant reduction in cell proliferation (>85%) after 72 h. Therefore, we confirmed the encapsulation and bioavailability of the drug, which was released in a controlled way, and the presence of chitosan delayed the release, which could be of interest for the development of prolonged release drug delivery systems.

3.
Chem Biol Drug Des ; 89(4): 529-537, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27696716

RESUMEN

Phenanthroline derivatives have been reported as potential bioactive compounds because of their ability to interact with DNA. To evaluate the antiproliferative effect of bis(acetylacetonate-k2 O,O)(1,10-phenanthroline-k2 N,N)Zn(II) or Zn(acac)2 (phen) complex, the compound was obtained in a simple manner and further characterized to determine crystal structure, thermal behavior, morphology, and spectroscopic properties. The structure of the complex was confirmed by X-ray single structure as well as by 1H and 13C nuclear magnetic resonance (NMR) in dmso-d6 (dimethyl sulfoxide) solution and in the solid state by 13C CP/MAS. Although preparation of this compound has been described previously, there are no reports on its biological activity; here, we assessed its antiproliferative effect on fibroblasts, A253, FaDu, Cal-27, RH-30, RD, U-373, C6, A-549, MDA-MB-231, and MCF-7 cancer cell lines at different doses (50-100 and 150 µg/ml). The cell viability was determined by MTT assay and high activity was observed for the most of the cell lines, and TUNEL results showed the induction of apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Fenantrolinas/química , Zinc/química , Línea Celular Tumoral , Cristalografía por Rayos X , Humanos , Etiquetado Corte-Fin in Situ , Técnicas In Vitro , Estructura Molecular , Fenantrolinas/farmacología , Difracción de Polvo , Espectrofotometría Infrarroja
4.
Medisur ; 13(4): 533-540, jul.-ago. 2015.
Artículo en Español | LILACS | ID: lil-760378

RESUMEN

En la práctica médica existen diversas situaciones que exigen inmediata permeabilización de la vía aérea en algunos pacientes, con el objetivo de garantizar una adecuada entrada y salida de gases a los pulmones y evitar la broncoaspiración. La intubación de secuencia rápida ha sido considerada como la administración de un agente hipnótico y un relajante neuromuscular de forma consecutiva (virtualmente simultánea) con el fin de facilitar la intubación orotraqueal en el paciente en estado crítico y minimizar el riesgo de aspiración. Este artículo pretende recopilar elementos que favorezcan una conducta médica acertada que obedezca a la situación presentada, pues no existe un patrón único de actuación ante la necesidad de intubación de secuencia rápida. Entre los elementos a tener en cuenta se destacan: contar con conocimientos anatómicos de las vías respiratorias superiores, disponer de un grupo de fármacos para elegir, tener entrenamiento adecuado y un plan alternativo ante la posibilidad de dificultades.


In medical practice there are several situations that require immediate intervention of the airway in some patients, in order to ensure proper entrance and exit of gases into and out of the lungs and prevent aspiration. Rapid-sequence intubation has been considered as the administration of a hypnotic agent and a neuromuscular relaxant consecutively (virtually simultaneously) to facilitate orotracheal intubation in critically ill patients and minimize the risk of aspiration. This paper aims to collect elements that promote a successful medical management according to the situation presented, since there is no single way of proceeding in case of rapid-sequence intubation. The elements to consider include: knowing the anatomy of the upper respiratory tract, having a group of drugs to choose from, receiving adequate training and having an alternative plan for the difficulties that may arise.

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