Desarrollo de andamios de matrices de biopolímeros estructuradas con aplicación en Ingeniería Tisular

La Ingeniería de Tejidos es un campo multidisciplinario donde interactúan diferentes ramas de la ciencia, como la química, la física, la medicina, la biología y la ingeniería. En los últimos años, el elemento más investigado de TE ha sido el andamio, que es una estructura que actúa como una plataforma de anclaje y adhesión para las células. De esta manera, estos andamios deben tener propiedades mecánicas y morfológicas bien diseñadas para promover el crecimiento óptimo de las células y su integración dentro del tejido. Las propiedades de los andamios dependen en gran medida del tipo de polímero utilizado y el método de procesamiento seguido para desarrollar estas estructuras. Por tanto, se debe hacer una caracterización previa de la materia prima para comprobar sus propiedades. Por tanto, el objetivo principal de este estudio ha consistido en el desarrollo de andamios con características adecuadas de porosidad, resistencia mecánica y biodegradabilidad, que sean viables para el desarrollo de tejidos musculares y biocompatibles, a partir de combinaciones de colágeno y gelatina con polímeros naturales (quitosano) o polímeros sintéticos. (PCL) La propuesta implica el uso de técnicas clásicas de procesamiento de polímeros, como el secado por liofilización, combinadas con técnicas novedosas destinadas a optimizar las propiedades de las matrices, como las técnicas de electrohilado o bioimpresión molecular. De los andamios, se han caracterizado tanto sus propiedades mecánicas como microestructurales. Además, se han seleccionado los más prometedores y se les ha realizado una evaluación biológica para comprobar su potencial para el desarrollo de tejido muscular

La enseñanza de biomateriales en el Grado de Ingeniería de los materiales

Se realizó un ciclo de mejora en la asignatura obligatoria Biomateriales que se imparte en los siguientes grados: Doble Grado en Química e Ingeniería de Materiales, Doble Grado en Física e Ingeniería de Materiales y Grado en Ingeniería de Materiales. La metodología llevada a cabo consiste en el análisis de un problema que se utiliza como punto de partida para el desarrollo de las distintas actividades. Los resultados reflejan un desarrollo en el aprendizaje de los alumnos, así como una valoración bastante positiva de ellos sobre esta metodología innovadora que se ha llevado a cabo, con una valoración media de 4.6 (sobre 5)

Participatory Methods in Discussion Forums: From press to classroom

El aprendizaje participativo es aquel en el que la persona que aprende juega un papel activo al intervenir propositivamente en la planeación, realización y evaluación del proceso de aprendizaje. En este aprendizaje, el alumno se convierte en un sujeto activo donde escucha activamente, opina, pregunta, sugiere, propone, decide, actúa, busca, expresa sus ideas y sus inquietudes. En este contexto el profesor actúa como dinamizador del proceso. Desde este punto de partida, se presenta esta experiencia donde, partiendo de situaciones y hechos de la vida cotidiana, se implica al alumno a involucrarse personalmente, pensar, sentir y actuar. Este trabajo expone la experiencia de un grupo de alumnos de la asignatura de Biomateriales del Grado Ingeniería de Materiales. El campo de los Biomateriales se encuentra en continua evolución y aparecen notas de prensa diariamente de los nuevos avances y logros obtenidos en ese campo. Aprovechando este contexto, se creó un foro donde los alumnos aportan semanalmente noticias encontradas en prensa relacionadas con el campo y, a su vez, pueden comentar las noticias de los compañeros. El profesor actúa como dinamizador comentando y abriendo debates con los alumnos a través del foro así como potenciando y fomentando su uso en las clases presenciales Finalmente, las noticias seleccionadas por parte de los alumnos se analizaron, se presentaron y debatieron con el resto de la clase. Todo este proceso permitió desarrollar la competencia general de “razonamiento crítico” ya que, los alumnos mostraron un carácter crítico frente al lenguaje utilizado frente al científico. Por otro lado, gracias a los conocimientos y actitudes adquiridos en la asignatura (competencias específicas) los alumnos usaron un lenguaje más adecuado, valoraron los logros presentados en las noticias, expusieron limitaciones de los mismos así como propusieron posibilidades de mejora. Al final de la experiencia, los alumnos valoraron muy positiva esta actividad mediante una encuesta pasada, sobre todo el hecho de considerarse motivados y protagonistas del proceso de aprendizaje.The participative learning is one that the learner plays an active role controlling the planning, performance and evaluation of the learning process. In this type of learning, the students are active persons who listen attentively, give opinions, ask, suggest, decide and they also explain their own ideas. In this context, the teacher acts like a process moderator. From this starting point, this experience is presented in which, taking into consideration day-to-day life facts, students involucrate themselves thinking, feeling and participating. In this work is exposed the experience of a group of students from the subject „Biomaterials‟ of the Materials Engineering degree. The Biomaterial field is continuously growing and there are daily news talking about the progress and success achieved in this field. In this context, a forum was created in order the students to include news every week, related with the Biomaterials field, and also leave a comment in other colleagues‟ news at the same time. The teacher acts as a moderator starting discussions with the students through the forum as well as enhancing its use during the class. Finally, the selected news are analysed, presented and discussed with the rest of the class. All this process could allow the development of the general competence „critical thinking‟ because the students showed a critical nature with the scientific language. Furthermore, the students used a more adequate language because of the knowledge and skills acquired in the subject (specific competences), and even, they assessed the achievements showed by the media and they exposed their opinions about the limitations and possible improvements of these scientific experiences. At the end of the activity, the students evaluate it as a very positive activity (with a survey), highlighting the facts of being motivates and important during the learning process

Desarrollo de geles bioactivos basados en residuos de la industria del arroz

La industria arrocera produce aproximadamente unos 100 millones de toneladas de residuos cada año. Aunque estos residuos tengan un alto contenido proteico, habitualmente se incineran debido a su alto poder calorífico. Sin embargo, existe una continua y creciente demanda de fuentes de proteína con el fin de poder satisfacer las necesidades de alimentación de la creciente población mundial. Una alternativa interesante sería el uso de concentrados proteicos provenientes de estos residuos para desarrollar productos alimentarios. En este sentido, se ha comprobado que la obtención de hidrolizados proteicos a partir de los concentrados proteicos puede ser una vía altamente interesante, aumentando la funcionalidad de estos sistemas. Por otra parte, en el caso de los productos alimentarios, las propiedades mecánicas no son las únicas que importan. De especial relevancia son las propiedades antioxidantes de estos productos. La evaluación de la capacidad antioxidante de estos sistemas puede llevarse a cabo mediante el empleo de diferentes técnicas. La presente contribución hace uso de un concentrado proteico de arroz (RPC) y dos hidrolizados (RPHA and RPHB) para el desarrollo de geles alimentarios. La caracterización llevada a cabo comprende tanto a la estructura de los sistemas, como a las de las propiedades antioxidantes de los mismos.Rice industry produces around 100 million tons of wastes every year. Although, these wastes generally exhibits a high protein content, they are burned due to its high calorific value. However, scientific community claims continuously for new protein sources in order to satisfy worldwide food requirements. In this sense, one alternative could be the use of protein concentrates from protein surpluses and wastes to develop new food products. Additionally, the use of protein hydrolysates could be very relevant since the functionality of protein may increase. Otherwise, not only the functionality of proteins is relevant in food products, but also the bioactive properties of them is a key factor. Among these bioactive properties, the evaluation of antioxidant properties of food products could involve the increase in value of these by-products. This work deals with the evaluation of a protein concentrate (RPC) and two different protein hydrolysates (RPHA and RPHB) in order to develop food-grade gels. The characterisation carried out include mechanical properties and antioxidant activity of the final gels.Plan Propio de la Universidad de Sevilla Proyecto: 2017/0000096

Fabrication and Characterization of Hydrogels Based on Gelatinised Collagen with Potential Application in Tissue Engineering

Regenerative medicine is increasingly focused on the development of biomaterials that facilitate cell adhesion and proliferation through the use of natural polymers, which have better biocompatibility and biodegradability. In this way, the use of hydrogels has been considered as a potential option for tissue engineering due to their physical and chemical characteristics. However, few studies associate the raw materials properties and processing conditions with the final characteristics of hydrogels, which could condition their use as scaffolds for tissue engineering. In this context, the main objective of this work was the evaluation of type I collagen as raw material for the elaboration of hydrogels. In addition, gelation time, pH and temperature were evaluated as the most influential variables in the hydrogel processing method by rheological (time, strain and frequency sweep tests) and microstructural (Cryo-SEM) measurements. The results indicate that it is possible to obtain collagen hydrogels with adequate rheological and microstructural characteristics by selecting optimal processing conditions. However, further studies are necessary to assess their suitability for cell accommodation and growth.Ministerio de Economía y Competitividad RTI2018-097100-B-C2

Micronutrient-controlled-release protein-based systems for horticulture: Micro vs. nanoparticles

Fertilization is an increasingly common practice in horticulture. Nevertheless, the conventionally used fertilization method is ineffective, and it generates contamination problems due to excess nutrients. Therefore, new technologies, such as nanofertilization or controlled-release systems of fertilizers, are currently being tested. Thus, the main objective of this work was to develop controlled-release systems for micronutrients, using soy protein as raw material. Different micronutrients (zinc, copper, iron, and manganese) were evaluated, as well as their incorporation in the form of micro and nanoparticles. The mechanical and functional properties (water uptake capacity, biodegradability, and micronutrient release) of the systems, as well as their use in crops, were studied to assess their viability. The results showed the great potential of these systems to incorporate micronutrients into crops, especially when combined with nanotechnology, improving the benefits of conventional fertilization. Download : Download high-res image (146KB) Download : Download full-size imageMEFP from Spanish Government for the predoctoral grant of Mercedes Jiménez Rosado FPU2017/01718Junta de Andalucía and Universidad de Sevilla for the postdoctoral grant of Victor Perez-Puyana (Talento Doctores, Junta de Andalucía con Fondo Social Europeo, Convocatoria 2019–20 DOC_0058

Polymer-based scaffolds for soft-tissue engineering

Biomaterials have been used since ancient times. However, it was not until the late 1960s when their development prospered, increasing the research on them. In recent years, the study of biomaterials has focused mainly on tissue regeneration, requiring a biomaterial that can support cells during their growth and fulfill the function of the replaced tissue until its regeneration. These materials, called scaffolds, have been developed with a wide variety of materials and processes, with the polymer ones being the most advanced. For this reason, the need arises for a review that compiles the techniques most used in the development of polymer-based scaffolds. This review has focused on three of the most used techniques: freeze-drying, electrospinning and 3D printing, focusing on current and future trends. In addition, the advantages and disadvantages of each of them have been compared.Ministerio de Economía y Competitividad RTI2018-097100-B-C2

Influences of the solid load on the microstructure and compressive behavior of Fe2O3 scaffolds manufactured by freeze-casting using stearic acid as dispersant agent

Porous materials manufactured by freeze-casting are demonstrating potential application as oxygen carriers for the production and purification of hydrogen, or anode material for lithium-ion batteries. However, to obtain the required pore morphology and sufficient mechanical strength, the suspension processing parameters must be controlled. Fe2O3 nanoparticles/camphene suspensions were fabricated using stearic acid as the dispersant agent showing a low-viscosity (130 mPa⋅s) with a high solid volume fraction (0.3). Suspensions show a shear-thinning behavior according to the Sisko model and a maximum packing fraction of 0.569 estimated from a zero porosity sample. A modified Krieger and Dougherty model was introduced to incorporate the influence of the particleaspect ratio. The Fe2O3 scaffolds manufactured by freeze-casting shown a gradient pore size along the freezing direction, which was diminished with the solid volume fraction, the compression strength was improved with the pore size reduction and fitted according to the minimum solid area model.Universidad de Sevilla PIF II.2AAgencia Estatal de Investigación (AEI) MAT2016-76713-

An analysis of different resources and programmes supporting at-risk families in Spain

The purpose of this research was to present an overview of the existing family support resources in Spain for at-risk families. We analysed 64 family support services from 16 agencies belong to 11 regions of Spain. In a second phase, 20 positive parenting programmes were analysed in depth to ascertain the extent to which they met evidence-based programme quality criteria. Our results suggest that services for at-risk families are delivered by public, local and social agencies. Most interventions were psycho-educational and aimed at parental training. The analysis of the positive parenting programmes ’ quality showed both strengths and weaknesses. Most programmes relied on a previous needs analysis and interventions were, to some extent, outlined in a manual. Nevertheless, few programmes have been evaluated according to evidence-based programme criteria. In light of these results, we discuss several practical implications for services and family support policies aimed at at-risk families.Ministerio de Economía y Competitividad de España EDU2013-41441-

Biodegradable soy protein-based tablets for the controlled release of zinc

[EN] Controlled-release systems are gaining interest in the horticultural industry to supply fertilizers to crops. However, their manufacturing process increases their cost, making its industrialization difficult. In this context, compaction of powders could be a low-cost and easily industrializable alternative. Thus, the main objective of this work was the manufacture of soy protein-based tablets with zinc (micronutrient) incorporated using different compaction parameters (pressure: 333, 416 and 777 MPa; post-manufacture heat treatment: 4 and 24 h). Thus, the mechanical (dynamic compression tests) and microstructural properties (SEM and grain number) of the different tablets were evaluated to study the effect of pressure and temperature on them. In addition, water uptake capacity and micronutrient release were studied. The latter has been analyzed with the use of two theoretical models (Higuchi and Korsmeyer-Peppas) to evaluate which model is the most accurate for predicting the zinc release of the different tablets. The results presented in this work demonstrate the great utility of soy protein-based tablets for the controlled release of zinc. Thus, this process allows the incorporation of 116 g of Zn in a kg product that can be released under control (9–10 h in water). These products have great industrial potential due to their ease of processing and properties, making them economically competitive.SIPublicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL