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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 120980, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35168033

RESUMEN

Using the proper size of nanoparticles as an active substrate, Surface-enhanced Raman scattering (SERS) can provide a reliable technique for detecting and identifying fungi, including Alternaria alternata, Aspergillus flavus, Fusarium verticilliodes, and Aspergillus parasiticus that have been associated to biodeterioration and biodegradation of cultural heritage materials. In this research spherical silver nanoparticles (AgNPs) of average size of 10, 30 and 60 nm were synthesized using the wet chemical method with good yield and their size and shape distributions were examined using small-angle X-ray scattering (SAXS). The protocol for fungi sample preparation proved to be critical for producing high-quality and reproducible SERS spectra. We found that the effect of AgNPs on SERS signal enhancement is size dependent under the same experimental conditions; the SERS intensity of fungal strains using 60 nm achieved up to 2.3x105 enhancement, about twice as intense as those produced with 30 nm, and 10 nm produced a minor broad weak peak barely discernible around 1400 cm-1, similar to the NR spectra profile in the 550-1700 cm-1 spectral region, and the SERS signals using 60 nm showed high reproducibility, with less than 20% variance. Furthermore, we used principal component analysis (PCA) to statistically classify the SERS spectrum into four separate clusters with 99 percent variability so that the four fungal strains could be clearly detected and identified. The SERS technique, in combination with the PCA developed in this study, provides a simple, rapid, accurate, and cost-effective analytical tool for detecting and identifying filamentous fungal strains.


Asunto(s)
Nanopartículas del Metal , Plata , Hongos , Reproducibilidad de los Resultados , Dispersión del Ángulo Pequeño , Espectrometría Raman/métodos , Difracción de Rayos X
2.
ERJ Open Res ; 7(3)2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34262972

RESUMEN

Each type of vaping device (vape pen, box Mod and JUUL), as well as nicotine and flavourings, induces a disparate metabolite profile or signature, such that each device and liquid is likely to lead to its own set of health effects https://bit.ly/3eExKzi.

3.
Am J Physiol Regul Integr Comp Physiol ; 314(6): R834-R847, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29384700

RESUMEN

Electronic (e)-cigarettes theoretically may be safer than conventional tobacco. However, our prior studies demonstrated direct adverse effects of e-cigarette vapor (EV) on airway cells, including decreased viability and function. We hypothesize that repetitive, chronic inhalation of EV will diminish airway barrier function, leading to inflammatory protein release into circulation, creating a systemic inflammatory state, ultimately leading to distant organ injury and dysfunction. C57BL/6 and CD-1 mice underwent nose only EV exposure daily for 3-6 mo, followed by cardiorenal physiological testing. Primary human bronchial epithelial cells were grown at an air-liquid interface and exposed to EV for 15 min daily for 3-5 days before functional testing. Daily inhalation of EV increased circulating proinflammatory and profibrotic proteins in both C57BL/6 and CD-1 mice: the greatest increases observed were in angiopoietin-1 (31-fold) and EGF (25-fold). Proinflammatory responses were recapitulated by daily EV exposures in vitro of human airway epithelium, with EV epithelium secreting higher IL-8 in response to infection (227 vs. 37 pg/ml, respectively; P < 0.05). Chronic EV inhalation in vivo reduced renal filtration by 20% ( P = 0.017). Fibrosis, assessed by Masson's trichrome and Picrosirius red staining, was increased in EV kidneys (1.86-fold, C57BL/6; 3.2-fold, CD-1; P < 0.05), heart (2.75-fold, C57BL/6 mice; P < 0.05), and liver (1.77-fold in CD-1; P < 0.0001). Gene expression changes demonstrated profibrotic pathway activation. EV inhalation altered cardiovascular function, with decreased heart rate ( P < 0.01), and elevated blood pressure ( P = 0.016). These data demonstrate that chronic inhalation of EV may lead to increased inflammation, organ damage, and cardiorenal and hepatic disease.


Asunto(s)
Barrera Alveolocapilar/efectos de los fármacos , Sistemas Electrónicos de Liberación de Nicotina , Inflamación/inducido químicamente , Nicotina/administración & dosificación , Nicotina/efectos adversos , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/efectos adversos , Animales , Citocinas/sangre , Femenino , Fibrosis/inducido químicamente , Expresión Génica/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Cultivo Primario de Células , Mucosa Respiratoria/citología , Mucosa Respiratoria/efectos de los fármacos , Sistema Respiratorio/efectos de los fármacos
4.
La Paz; 1991. 157 p. ilus.
Tesis en Español | LIBOCS, LIBOSP | ID: biblio-1310996

RESUMEN

Se ha formulado matematico para el proceso simultaneo de difusion y adsorcion de soluciones aurociarnuradas mediante carbon activado, a nivel de los granulos de carbon, asumiendo una geometria esferica y una isoteras lineal, este transformado en parametros adimensionales ha sido resuelto analiticamente. el modelo es aplicable, tanto para caracterizar el proceso fenomenologico de la cinetica de transferencia intragranular del aurocianuro desde la solucion hasta los sitios activos de adsorcion en el interior del carbon activado, asi como para la determinacion de difusividades efectivas, mediante correlacion de datos experimentales en el mismo. Se ha demostrado fenomenologicamente que la transferencia de adsorbato en el interior del adsorbente esta limitado por un mecanismo de difusion intraganular.

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