Motivos de elección de una asignatura por parte de los alumnos / Some reasons which could induce to the students to choose an academic subject

El motivo de elección de una determinada asignatura por parte de los alumnos, ha sidofrecuentemente interpretado bajo diferentes puntos de vista. En esta comunicación nuestro objetivo hasido analizar los motivos de elección en distintos tipos de asignaturas con características peculiarescada una de ellas, concretamente dos de ellas son de libre configuración, siendo una de impartición enel campus andaluz virtual –Fotoprotección- y la otra en el campus virtual de la Universidad deGranada –Aplicación de la Tecnología Farmacéutica en el tratamiento del cáncer y del dolor-. Latercera asignatura seleccionada es una optativa -Farmacia Práctica- que se imparte actualmente en laLicenciatura en Farmacia. Se ha realizado un análisis de los diferentes motivos que impulsan a unalumno a la elección de una disciplina frente a otra, para ello se ha utilizado una de las herramientas demayor uso, la encuesta anónima a todos aquellos que estaban matriculados. Las conclusiones de esteestudio son diversas pero ante todo cabe señalar en el caso de las virtuales la facilidad de acceso yrealización de las asignaturas virtuales, y destacar también que un título atractivo es fundamental en suelección. En el caso de la optativa el motivo fundamental ha sido aprender algo nuevo relacionado consu licenciatura y seguido muy de cerca por la facilidad de horario. Por tanto como conclusióndefinitiva es interesante destacar que tanto en un caso como en otro el alumno desea aprender algoatractivo y que se acomode fácilmente a su horario de estudio(AU)

The reason why a specific subject is chosen by the students has been frequently interpretedfrom several points of view. The aim of this study is to analyze the reasons why different types ofsubjects with particular characteristics are chosen. Specifically, two of these subjects are freeelectives: one of them –Fotoprotección- is imparted through the Andalusian Virtual Campus, and theother one –Aplicación de la Tecnología Farmacéutica en el tratamiento del cáncer y del dolorthroughthe virtual campus of the University of Granada. The third subject chosen is optional -Farmacia Práctica- and it is at present imparted within the Degree in Pharmacy. The different reasonswhy a student chooses one subject against other have been analyzed using one of the most used tools:an anonymous survey to all the students enrolled. The conclusions of this study are diverse, but it ismainly to be remarked in the case of the virtual subjects their accessibility and easy implementation aswell as the importance of an attractive title for the selection of a subject. The main reason in the caseof the optional subject is to learn something new in relation to their Degree, followed very closely byits timetable. Therefore, as final conclusion, it is interesting to remark that the students want in bothcases to learn something attractive that can be easily adapted to their study schedule(AU)

Organoclay particles as reinforcing agents in polysaccharide films.

In this work an investigation is described on the use of organically modified montmorillonite clay particles as stabilizers of bioplastic films based on xylan. With the aim of facilitating the incorporation of the nanoparticles to the films, the former were treated with a non-ionic surfactant, inulin. In order to evaluate the possible role of electrostatic interactions in the formation of montmorillonite/xylan complexes, an exhaustive electrokinetic characterization of the modified montmorillonite was carried out. Because montmorillonite has been modified by adsorption of the cationic surfactant DSDMAC, the electrophoretic mobility of montmorillonite in the absence of inulin is positive in a wide range of concentration of NaCl and CaCl(2). On the contrary, addition of KBr provokes a charge inversion when the salt concentration is around 0.05 M, suggesting adsorption of Br(-) ions. In the presence of inulin, the positive electrophoretic mobility decreases with the concentration of this surfactant, and this can be explained by assuming that inulin adsorption is accompanied by simultaneous DSDMAC desorption, eventually producing charge inversion, particularly in the presence of bromide ions. A thorough characterization of the wettability of the xylan films demonstrated that it is dominated by acid-base interactions and that incorporation of inulin-coated montmorillonite leads to a considerable reduction of the hydrophilic character of the films.

Preparation, characterization, and in vitro release of new transdermal methimazole as alternative to oral delivery.

Our objective has been the development and study of the stability of transdermal methimazole formulae as alternative to oral administration. Preparation of F-127 and PLO Pluronic gel (Pluronic lecitin organogel) are described, as well as their characteristics from transmission electron microscopy. The possible structural and rheological changes to both transdermal forms were studied in terms of composition, temperature and time. The trial period was from 24 hr to 3 months after preparation. Furthermore, identical tests were carried out on formulae conserved for 1 year after production to check their integrity. Studies of release in vitro were carried out showing that the selected excipients do not pose an obstacle to the cession of methimazole, even though the PLO samples were made more slowly.

Spectrophotometric and chromatographic determination of omeprazole in pharmaceutical formulations.

The purpose of this study was to determine the stability of the pH sensitive drug, omeprazole, within different solid oral pharmaceutical formulations and to determine whether the addition of antacid and surfactant agents, at varying concentrations, influenced drug stability and release. Spectrophotometric and chromatographic techniques were used for evaluation purposes, giving good results concerning linearity, precision and specificity within the range of concentrations used in this study. However, the results show that the degradation products of omeprazole interfere with spectrophotometric evaluation, making this technique insufficiently selective for omeprazole. On the other hand, liquid chromotography proved to be more sensitive, accurate and precise. Additionally, in an attempt to improve the administration form of the drug, an extemporaneous suspension was designed, which after evaluation proved to be a satisfactory administration vehicle. The best formulation of omeprazole studied is: omeprazole: 0.5%; corn starch 34.2%; aluminum hydroxide 26%; magnesium hydroxide 13%; simple syrup 24.8%; SDS 1%.

Determinación de la estabilidad de Kollicoat MAE 30D mediante medidas de calorimetría diferencial de barrido / Determination of the stability of Kollicoat MAE 30D by means of differential scanning calorimetry

Se estudia la estabilidad de Kollicoat MAE 30D mediante determinaciones calorimétricas y microscópicas. Se estudian los efectos que producen pH, temperatura y agitación sobre las propiedades fisicoquímicas de las partículas de este látex comercial. Se comprueba que el factor que más influencia ejerce es el pH, siendo máxima la estabilidad a pH ácidos, y modificándose con un decrecimiento de la misma, a partir de pH 6. Se determina la forma y tamaño de partícula mediante medidas microfotográficas de SEM, realizando el recuento de 200 partículas de una muestra del látex previamente desecado. Se comprueba que la dispersión acuosa de Kollicoat MAE 30 D a su pH natural(2.5), da lugar a una población de partículas con un diámetro medio de 1.56 nm (AU)

The stability of Kollico at MAE 30 D was studied with differential scanning calorimetric, and scanning electron microscopy. We investigated the effects of pH, temperature and shaking on physicochemical properties of the latex particles. Stability of the polymer as most strongly affected by pH; hence, we conclude that the stability of this latex reaches a maximum at acid pH values, whereas stability is lost to pH 6.The particle shape and the mean diameter were determined by means of SEM microphotographs on 200 particles in a sample of dry latex. The aqueous Kollico at MAE 30 D dispersion, at its natural pH (2.5), presented one population of particles with a mean diameter of 1.56 nm (AU)

Partículas superparamagnéticas ultrapequeñas de óxido de hierro para aplicaciones biomédicas / Ultrasmall superparamagnetic iron oxide particles for biomedical applications

Las partículas superparamagnéticas ultrapequeñas de óxido de hierro (USPIO) tienen una enorme utilidad enBiomedicina como agentes de contraste en resonancia magnética de imagen o como sistemas transportadores defármacos, entre otras aplicaciones. La naturaleza del recubrimiento de los núcleos inorgánicos de las partículasUSPIO determina su estabilidad in vitro y su comportamiento in vivo, siendo especialmente importantes sus propiedadesfi sicoquímicas, en concreto el tamaño, la carga superfi cial y la densidad del recubrimiento. Las pequeñasdimensiones de las partículas USPIO hace difícil una caracterización fi sicoquímica completa, la cuál es de sumaimportancia para poder mejorar su estabilidad y comportamiento in vivo. Esta revisión se centra en las técnicasinstrumentales utilizadas en el análisis de los núcleos magnéticos y de sus recubrimientos orgánicos

Ultrasmall superparamagnetic iron oxide (USPIO) particles are iron oxide nanoparticles currently used for Biomedicalapplications: contrast agents in magnetic resonance imaging, drug delivery systems, etc. The coatings surrounding theUSPIO inorganic core may control the in vitro stability and the in vivo fate. Different physicochemical properties suchas the fi nal size, the surface charge and the density of coverage are key factors in this respect. A complete physicochemicalcharacterization of USPIOs particles is diffi cult due to their small dimensions. However, such a characterizationis necessary to improve the stability of the particles and their in vivo behaviour. This review is focused on thetechniques which can be applied to have a better insight in the magnetic core structure of these particles and theirorganic surface

Development of carbonyl iron/ethylcellulose core/shell nanoparticles for biomedical applications.

A reproducible method for the preparation of mixed colloidal nanoparticles, consisting of a magnetic carbonyl iron nucleus and a biocompatible ethylcellulose latex shell, is described in this article. The heterogeneous structure of the particles can confer them both the possibility of being used as drug delivery systems and the responsiveness to external magnetic fields, allowing a selective guidance of drug molecules to specific target tissues without a concurrent increase in its level in healthy tissues. The preparation method is based on an emulsion solvent evaporation process. A complete physicochemical characterization of the composite particles was carried out, and this preliminary investigation showed that the surface behavior of the core/shell particles is similar to that of bare ethylcellulose particles. This was confirmed, in particular, by zeta potential determinations as a function of pH and ionic strength. This fact points to the ethylcellulose shell efficiently coating carbonyl iron, and leading to composite particles which, from the electrokinetic point of view, are almost indistinguishable from latex. The thermodynamic analysis agrees with the electrokinetic one in suggesting that the coverage has been complete, since the components of the surface free energy of mixed particles coincide almost exactly with those corresponding to the cellulose-based pseudolatex. Moreover, the hydrophilic nature of carbonyl iron is modified and the particles become hydrophobic, just like the latex, when they are covered by ethylcellulose. The magnetic behaviors of the carbonyl iron and composite particles were also checked, and the similarities between both types of particles were demonstrated, except that the polymeric shell reduces the magnetization of the sample.