Statistical analysis of solid lipid nanoparticles produced by high-pressure homogenization : a practical prediction approach

Lipid nanoparticles (LNPs) are a promising carrier for all administration routes due to their safety, small size, and high loading of lipophilic compounds. Among the LNP production techniques, the easy scale-up, lack of organic solvents, and short production times of the high-pressure homogenization technique (HPH) make this method stand out. In this study, a statistical analysis was applied to the production of LNP by HPH. Spherical LNPs with mean size ranging from 65 nm to 11.623 lm, negative zeta potential under –30 mV, and smooth surface were produced. Manageable equations based on commonly used parameters in the pharmaceutical field were obtained. The lipid to emulsifier ratio (RL/S) was proved to statistically explain the influence of oil phase and surfactant concentration on final nanoparticles size. Besides, the homogenization pressure was found to ultimately determine LNP size for a given RL/S, while the number of passes applied mainly determined polydispersion. a-Tocopherol was used as a model drug to illustrate release properties of LNP as a function of particle size, which was optimized by the regression models. This study is intended as a first step to optimize production conditions prior to LNP production at both laboratory and industrial scale from an eminently practical approach, based on parameters extensively used in formulation

Receptor-targeted nanoparticles modulate cannabinoid anticancer activity through delayed cell internalization

Δ9-tetrahydrocannabinol (Δ9-THC) is known for its antitumor activity and palliative effects. However, its unfavorable physicochemical and biopharmaceutical properties, including low bioavailability, psychotropic side effects and resistance mechanisms associated to dosing make mandatory the development of successful drug delivery systems. In this work, transferring (Tf) surface-modified Δ9-THC-loaded poly(lactide-co-glycolic) nanoparticles (Tf-THC-PLGA NPs) were proposed and evaluated as novel THC-based anticancer therapy. Furthermore, in order to assess the interaction of both the nanocarrier and the loaded drug with cancer cells, a double-fluorescent strategy was applied, including the chemical conjugation of a dye to the nanoparticle polymer along with the encapsulation of either a lipophilic or a hydrophilic dye. Tf-THC PLGA NPs exerted a cell viability decreased down to 17% vs. 88% of plain nanoparticles, while their internalization was significantly slower than plain nanoparticles. Uptake studies in the presence of inhibitors indicated that the nanoparticles were internalized through cholesterol-associated and clathrin-mediated mechanisms. Overall, Tf-modification of PLGA NPs showed to be a highly promising approach for Δ9-THC-based antitumor therapies, potentially maximizing the amount of drug released in a sustained manner at the surface of cells bearing cannabinoid receptors.España Junta Andalucía Project Nr. P09- CTS502

The Importance of Sustainability in the Loyalty to a Tourist Destination through the Management of Expectations and Experiences

Sustainability has become one of the key factors for the development of tourism both nowadays and in the future. The need to integrate environmental, socio-cultural and economic factors is a consequence of the evolution of society itself, the introduction of new information and communication technologies (ICTs) and a new way of understanding tourism and the world in general. Tourists increasingly seek a unique quality in their travels and are better informed before deciding on a tourist destination to spend their holidays or leisure time. They want to have unique, memorable experiences, and because of that, they are willing to look for those destinations that can o er them something di erent. The generation of expectations is no longer the sole responsibility of companies and public and private organizations in destinations, since information may be in the hands of the individuals themselves who can share it in social networks, blogs, or on platforms such as Booking or TripAdvisor, among others. This forces companies and public and private organizations to rethink the way in which and when they relate to tourists in general. With all these considerations, one of the objectives of this study was to analyse the way in which sustainability interrelates with the generation of expectations, experiences and perceptions and the e ect on the possibilities of returning to a tourist destination and even recommending it in social networks to friends and acquaintances. For this reason, the destination of Acapulco, Guerrero, Mexico, was chosen, a mature destination of sun and beach that, in recent years, has been immersed in a process of change where one of the axes is sustainability. This study used a convenience survey with 310 valid questionnaires with tourists who stayed more than three days in Acapulco during the months of December 2016 to February 2017. The questionnaires were completed at di erent points of the destination and by participants over 18 years of age. We used SEM (Structural Equations Modeling) and EQS (Structural Equation Modeling Software) for statistical analysis. The results of the study showed how expectations influenced experiences and the intention to return to the destination and recommend it (WOM), thus, we proposed a series of recommendations for public and private agents that manage this tourist destination

Interés terapéutico de cannabinoides: análisis bibliométrico en Pubmed, Scopus y web of Science

En este trabajo se ha analizado la actividad científica mundial sobre la aplicación terapéutica de cannabinoides en diferentes patologías, así como la posible aplicación de la nanotecnología en el desarrollo de nuevos sistemas de administración para este tipo de fármacos. Para ello, se han utilizado tres bases de datos habituales en Ciencias de la Salud: PubMed, Scopus y Web of Science (WoS). Los resultados del análisis muestran claramente un interés creciente en estas moléculas y sus posibles aplicaciones terapéuticas. El análisis se ha hecho comparando los resultados para el ítem cannabinoids en las tres bases de datos y su asociación con therapeutic. Como se muestra en el trabajo, para Scopus y WoS se obtienen tendencias similares aunque el número de documentos recogidos en Scopus entre 2007-2012 es menor que en WOS. Por el contrario, PubMed muestra una tendencia totalmente discordante. Respecto a la aplicación de la nanotecnología en el desarrollo de nuevos sistemas de administración de estos fármacos, Scopus no diferencia los resultados para los ítems nanotechnology y microspheres. Para la asociación nanoparticles + cannabinoids, Scopus y WoS es la que vuelca más resultados, con un total de 10 artículos de investigación, siendo el 40 % de ellos españole

Magnetic Anomalies in Extensional Detachments: The Xistral Tectonic Window of the Lugo Dome (NW Spain)

[EN]Magnetic anomalies in the Lugo gneiss dome of the NW Iberian Massif are related with outcropping late Variscan extensional detachments The sources of magnetic anomalies are high‐grade metamorphic rocks, including migmatites and inhomogeneous granites The Lugo Dome is one of a series that coincides with a broad, curved magnetic anomaly that delineates an orocline in NW Iberi

Characterization of the Eastern Galicia Magnetic Anomaly. A warning regarding the interpretation of aeromagnetic data

[EN]Caution should be applied to the interpretation of aeromagnetic data since often they use unknown geological bodies of unknown characteristics to explain the anomalies. A case study in the Lugo Sanabria Extensional Dome (NW Spain) shows that what was interpreted as an anomaly sourced by a basic/ultrabasic magnetic body from the lower crust/mantle, seems to be related to magnetization along extensional detachments in relation to the orogenic evolution of a thickenend Variscan crust

Cannabinoid derivate-loaded PLGA nanocarriers for oral administration: formulation, characterization, and cytotoxicity studies

CB13 (1-Naphthalenyl[4-(pentyloxy)-1-naphthalenyl]methanone)-loaded poly(lactic-co-glycolic acid) nanoparticles (NPs) were produced by nanoprecipitation and tested for their in vitro release behavior and in vitro cytotoxicity assays. The effects of several formulation parameters such as polymer type, surfactant concentration, and initial drug amount were studied. NPs had a particle size 90–300 nm in diameter. Results obtained show that the main influence on particle size was the type of polymer employed during the particle production: the greater the hydrophobicity, the smaller the particle size. In terms of encapsulation efficiency (%), high values were achieved (∼68%–90%) for all formulations prepared due to the poor solubility of CB13 in the external aqueous phase. Moreover, an inverse relationship between release rate and NP size was found. On the other hand, low molecular weight and low lactide content resulted in a less hydrophobic polymer with increased rates of water absorption, hydrolysis, and erosion. NPs showed no cytotoxicity and may be considered to be appropriate for drug-delivery purposes

Magnetic anomalies associated to extensional detachments? An example at Xistral TectonicWindow of the Lugo Dome (NW Spain)

[EN]Magnetic anomalies in the Lugo gneiss dome of the NW Iberian Massif are related with outcropping late Variscan extensional detachments The sources of magnetic anomalies are high‐grade metamorphic rocks, including migmatites and inhomogeneous granites The Lugo Dome is one of a series that coincides with a broad, curved magnetic anomaly that delineates an orocline in NW Iberi

Aportes para la enseñanza de la escritura

Se organiza en cinco secciones. La primera presenta el enfoque de la enseñanza de la escritura en la región, a partir de la revisión del análisis curricular que sirve como marco de evaluación de las pruebas, especificando los propósitos, objetivos, características y orientación de la enseñanza de esta disciplina. La segunda describe la prueba TERCE, relevando los aprendizajes que evalúa a partir de las dimensiones e indicadores que componen las rúbricas con que se corrigieron los textos producidos por los estudiantes. La tercera sección analiza los resultados de los estudiantes en los indicadores evaluados en las pruebas de tercer y sexto grados. En la cuarta sección se muestran ejemplos de respuestas que representan distintos niveles de logro y, en la quinta, se entregan sugerencias o propuestas de prácticas pedagógicas para promover que los estudiantes alcancen los niveles más avanzados

Modelling electro-scrubbers for removal of VOCs

This work focuses on the development and testing of simple phenomenological models for understanding the behaviour of processes happening at the same time in the electro-scrubbers during the electrochemically assisted absorption of two relevant volatile organic compounds: perchloroethylene and toluene. Formulation of the model considers physical absorption of the organics into the electrolyte and reactivity according to experimental observations. Different experimental case studies have been used to validate the model obtaining regression coefficients higher than 0.9 and 0.85 for perchloroethylene and toluene, respectively. The model points out the high relevance of the absorption technology and of the presence of cobalt. In the case of perchloroethylene, the model also highlighted the important contribution of the wet decomposition of this chlorinated hydrocarbon. Results obtained clearly evidence the industrial application of the electro-scrubbers technologies