Search results for "PreP"
showing 10 items of 1334 documents
Mucoadhesive polymers for oral transmucosal drug delivery: a review.
2012
The oral mucosa offers an interesting site for the application of dosage forms that release drugs within/throughout the oral mucosa, by assuring a high drug bioavailability for topic and systemic effects. However, the relative permeability of the oral mucosa and the washing effect related to the oral fluids and mechanical stresses must be considered in the formulation of oral dosage forms. Since a sustained drug release can be guaranteed only if dosage forms remain in contact with the oral site of absorption/application for a prolonged time, the development of mucoadhesive dosage forms is mandatory. The mucoadhesion is a complex phenomenon and the mucoadhesive bond consists of two different…
Statistical Analysis of a Method to Predict Drug–Polymer Miscibility
2015
In this study, a method proposed to predict drug-polymer miscibility from differential scanning calorimetry measurements was subjected to statistical analysis. The method is relatively fast and inexpensive and has gained popularity as a result of the increasing interest in the formulation of drugs as amorphous solid dispersions. However, it does not include a standard statistical assessment of the experimental uncertainty by means of a confidence interval. In addition, it applies a routine mathematical operation known as "transformation to linearity," which previously has been shown to be subject to a substantial bias. The statistical analysis performed in this present study revealed that t…
Poly(lactic acid)/carvacrol-based materials: preparation, physicochemical properties, and antimicrobial activity
2020
The current demand for new antimicrobial systems has stimulated research for the development of poly(lactic acid)/carvacrol (PLA/CAR)-based materials able to hinder the growth and spread of microorganisms. The eco-friendly characteristics of PLA and cytocompatibility make it very promising in the perspective of green chemistry applications as material for food and biomedical employments. The broad-spectrum biological and pharmacological properties of CAR, including antimicrobial activity, make it an interesting bioactive molecule that can be easily compounded with PLA by adopting the same techniques as those commonly used for PLA manufacturing. This review critically discusses the most comm…
Resveratrol, a polyphenolic phytoalexin present in red wine, enhances expression and activity of endothelial nitric oxide synthase.
2002
Background— Estrogens can upregulate endothelial nitric oxide synthase (eNOS) in human endothelial cells by increasing eNOS promoter activity and enhancing the binding activity of the transcription factor Sp1. Resveratrol, a polyphenolic phytoalexin found in grapes and wine, has been reported to act as an agonist at the estrogen receptor. Therefore, we tested the effect of this putative phytoestrogen on eNOS expression in human endothelial cells. Methods and Results— Incubation of human umbilical vein endothelial cells (HUVEC) and HUVEC-derived EA.hy 926 cells with resveratrol for 24 to 72 hours upregulated eNOS mRNA expression in a time- and concentration-dependent manner (up to 2.8-fold)…
Risk perception, knowledge, prevention, information sources and efficacy beliefs related to Covid-19
2020
Abstract Background Sars-Cov-2 is one of the latest examples of an emerging infectious disease challenging the world and it is the third case, in just two decades, of “spillover”. In light of the recent outbreak (Italy is in 2nd position), it is important to evaluate people risk perception and to support the Health Authority with effective communicative actions to avoid the spread of “infodemia”/alarmism. The aim of this study is a) to study levels of perceived threat, risk perception, severity and comparative vulnerability b) to compare risk perception with other communicable/not communicable diseases; c) provide information to increase awareness/ knowledge of the disease. Methods We perfo…
La formación inicial del profesorado de Educación Secundaria: una mirada comparativa en la Unión Europea
2011
El artículo comienza exponiendo los modelos que se han utilizado en la formación del profesorado de Secundaria y sus características, para adentrarse en el modelo de formación español y analizarlo a la luz de esos paradigmas formativos. Posteriormente se describe el cambio realizado en España con la introducción del Máster de Formación del Profesorado de Secundaria, estudiando el efecto de los cambios y las dificultades habidas en su introducción. En la segunda parte se analiza la formación de los docentes europeos desde variables como el modelo formativo, los salarios, el tiempo de trabajo o la jubilación, y se establece una serie de conclusiones finales sobre la realidad y la prospectiva …
Prebióticos y nucleótidos en alimentación infantil: revisión de la evidencia
2012
Introducción: Una gran mayoría de preparados infantiles de inicio y continuación comercializados en España presentan en su formulación prebióticos y/o nucleótidos, con objeto de lograr efectos beneficiosos en la prevención de diferentes patologías y protección inmunológica, similares a los de la leche materna. No obstante, atendiendo a la reglamentación vigente, su adición es opcional, ya que no existe suficiente evidencia científica que certifique la obligatoriedad de su inclusión. Objetivo: Revisar sistemáticamente la evidencia científica proveniente de estudios clínicos aleatorizados con grupo control que permita determinar el papel beneficioso para la salud de los lactantes derivada de …
Analysis of toxic elements in plastic components for toys. Multi-elemental determination by x-ray fluorescence
1993
Abstract An x-ray fluorescence method is proposed for the multi-elemental determination of toxic elements in plastic articles for children, viz., Sb(III), Ba, Cd, Cr(III), Hg, Pb and As(III). Mineralization is achieved by using molten sodium hydroxide to decompose the organic matrix, with sodium nitrate as auxiliary oxidant. Stable solutions containing the chemical species for analysis are obtained. The species are separated from the solution by (co)precipitation, in a medium of NH+4-NH3 buffer (pH 8.5) with sodium diethyldithiocarbamate, sodium rhodizonate and Fe3+, which acts as a carrier. The precipitates deposited on filter-paper are placed in the x-ray spectrometer in fine layer morpho…
Caracterización de esteroles, lípidos polares, ácido siálico y gangliósidos en la alimentación del lactante
2017
La leche humana (LH) es el alimento idóneo para los lactantes durante los primeros 6 meses de vida y en su defecto, se recurre a preparados para lactantes (PL). A estos PL, con el propósito de asemejarlos a la LH, se le añaden ingredientes como aceites vegetales, membrana del glóbulo graso de la leche (MFGM), grasa láctea, etc., que aportan compuestos bioactivos (esteroles, fosfolípidos y esfingolípidos (lípidos polares –LP), ácido siálico (Sia) y gangliósidos (GG)), presentes de forma natural en la LH, con grandes efectos en los lactantes. El objetivo de este trabajo es, conocida la importancia del colesterol, LP, Sia y GG en la alimentación infantil, evaluar las posibles diferencias entre…
Sensitivity of whole wood stable carbon and oxygen isotope values to milling procedures
2014
RATIONALE Milling of wood samples is a widely applied preparation method for pooling tree-rings from different trees or periods of several years for determination of δ13C and δ18O values. In this study, whole wood samples were milled using different procedures in order to evaluate potential effects of this preparation method on δ13C and δ18O values. METHODS Subsamples of a 5 cm3 wood piece of a single tree-ring from a lowland white fir were used. The samples were milled with different setups: (i) two and three stainless-steel balls, (ii) 3, 5 and 8 min milling time, and (iii) discontinuous and continuous milling. The δ13C values were measured using an elemental analyser connected to an IsoP…