Janus 3D Printed Dynamic Scaffolds for Nanovibration-Driven Bone Regeneration

The application of physical stimuli to cell cultures has shown potential to modulate multiple cellular functions including migration, differentiation and survival. However, the relevance of these invitro models to future potential extrapolation invivo depends on whether stimuli can be applied "externally", without invasive procedures. Here, we report on the fabrication and exploitation of dynamic additive-manufactured Janus scaffolds that are activated on-command via external application of ultrasounds, resulting in a mechanical nanovibration that is transmitted to the surrounding cells. Janus scaffolds were spontaneously formed via phase-segregation of biodegradable polycaprolactone (PCL) and polylactide (PLA) blends during the manufacturing process and behave as ultrasound transducers (acoustic to mechanical) where the PLA and PCL phases represent the active and backing materials, respectively. Remote stimulation of Janus scaffolds led to enhanced cell proliferation, matrix deposition and osteogenic differentiation of seeded human bone marrow derived stromal cells (hBMSCs) via formation and activation of voltage-gated calcium ion channelsThe authors acknowledge the Texas A&M Health Science Center College of Medicine Institute for Regenerative Medicine at Scott & White who isolated and provided the cells through a grant from NCRR of the NIH (Grant #P40RR017447). The authors acknowledge the financial support from the European Commission under the ERC starting grant “Cell Hybridge” of the Horizon2020 framework program (Grant # 637308)

Stimuli responsive nanocomposites based on cellulose nanocrystals

Cellulose nanocrystals (CNCs) are high-aspect ratio, mechanically stiff fibers which can serve as both a bio-renewable reinforcing agent in nanocomposites, as well as a handle for adding stimuli responsiveness. CNCs can be extracted from a wide range of natural cellulosic materials, with characteristics such as crystal structure, crystallinity and aspect ratio fluctuate widely between sources. Here, we report small molecule functionalized cellulose prepared for sustained delivery in a variety of environments. Moieties attached to the surface of cellulose nanocrystals show that both irreversible and reversible changes can be induced by application of an external stimuli. Moreover, we present the case of articular cartilage, which serves as a low-friction cushion in synovial joints and is vital for mam­malian skeletal movements. Due to its avascular nature and the low cell density, the tissue has a limited ability to regenerate, and damage due to injury, wear and tear, or disease usually requires surgical intervention. While articular cartilage had been predicted to be one of the first tissues to be successfully engineered, it proved to be challenging to reproduce the complex architecture and biomechanical properties of the native tissue. Here we report the fabrication of multi-layer polymer nanocomposite scaffolds that mimic the structural design, chemical cues, and mechanical characteristics of mature articular cartilage. These scaffolds guide the morphology, orientation, and phenotypic state of cultured chondrocytes in a spatially controlled manner, support the growth of tissue with features that are reminiscent of the natural analogue, and promote localized hydroxyapatite formation to permit integration with the subchondral bone

Mejora de masas panarias integrales bajas en sodio

[ES] En el presente trabajo se ha planteado el uso de Salvia hispánica (Chía) para la mejora del procesado de masas panarias integrales bajas en sodio. Para ello se evaluó la mejor combinación de salvado (harina integral) y chía que mejore el rendimiento productivo del pan, así como la incidencia del uso de 2 sustitutos comerciales de la sal. El análisis de imagen 3D de la fermentación, así como los fisicoquímicos realizados a los panes una vez elaborados, mostraron que la formulación realizada con un 13% de salvado y un 4% de Chía es la que presenta el mejor resultado, llegando a igualar el obtenido por panes donde se utiliza harina refinada. Los resultados obtenidos para los sustitutivos comerciales empleados si bien no influyeron en las variables de procesado evaluadas, sí que influyeron negativamente sobre la apreciación global de los panes como consecuencia de los atributos evaluados ligados al sabor (intensidad de salado, sabor residual y aceptación del sabor salado).[EN] In this study Salvia hispánica (Chia) has been used for the improvement of wholemeal low sodium doughs yield. It was evaluated the best combination of bran (wholemeal flour) and Chia for the improvement of dough yield, and the incidence of two salt commercial substitutes. With 3D image analysis and other psycochemical analysis made to breads once elaborated, it showed that the formulation with 13% of bran and 4% of Chia is the best which has the best results. It equalizes the refined flour doughs results. The results obtained with the use of salt substitutes did not influence the process variables studied, but they have a little negative influence in sensorial aspects, like salty taste intensity, aftertaste and salty taste acceptance.Camarero Pavía, S. (2014). Mejora de masas panarias integrales bajas en sodio. http://hdl.handle.net/10251/40121.Archivo delegad

Aplicación de la técnica de imagen hiperespectral para la inspección de mezclas de carnes de diferentes animales

[ES] En el presente trabajo se pretende evaluar la eficacia de la técnica de imagen hiperespectral en la detección de posibles adulteraciones en materia prima cárnica, más concretamente presencia de carne de potro en cerdo o en ternera. Para ello se realizaron mezclas binarias de las carnes a diferentes proporciones (1% a 100%) las cuales fueron evaluadas mediante la técnica de imagen y caracterizadas mediante análisis fisicoquímicos. El análisis de los resultados ha mostrado como la técnica de imagen hiperespectral es válida para la detección de la presencia de carne de potro en cerdo o en ternera, con un umbral de detección del 1%. Así los espectros que caracterizan cada muestra han presentado picos característicos que se relacionan directamente con las características fisicoquímicas evaluadas.[EN] This work aims to evaluate the efficacy of imaging hyperspectral technique in the detection of possible adulterants in raw meat, mainly foal meat in pork and veal meat. Meat mixtures will be done (1% to 100%) in order to evaluate the detection limit. Results show that the hyperspectral image technique is able to cluster samples with a minimum of 1% of foal in pork and veal meat. In addition spectrum which characterizes each sample has an interesting picks which are related with the physicochemical properties of the evaluated samples.[CA] En el present treball es pretén avaluar l'eficàcia de la tècnica d'imatge hiperespectal en la detecció de possibles adulteracions en matèria primera cárnica, en concret presencia de carn de poltre en carn de porc i vedella. Per a açò es realitzaran mescles de carns en diferents proporcions (1% a 100%), que foren avaluades mitjançant la tècnica d’imatge i anàlisis fisicoquímics. L’anàlisi de resultats ha mostrat com la tècnica d’imatge es capaç de detectar la presencia de poltre en un 1% en carn de porc y vedella. Així els espectres que caracteritzen cada mostra han presentat pics que han segut relacionats directament amb les característiques fisicoquímiques avaluades.Camarero Pavía, S. (2015). Aplicación de la técnica de imagen hiperespectral para la inspección de mezclas de carnes de diferentes animales. http://hdl.handle.net/10251/60420.TFG

Low molecular weight poly((d,l)-lactide-co-caprolactone) liquid inks for diluent-free DLP printing of cell culture platforms

Digital light processing (DLP) printing offers the possibility of fabricating complex objects in a fast and reproducible manner. A main requirement for DLP printing is the use of inks with low viscosities that can flow under the printing platform in a short period of time. Its exploitation in tissue engineering applications has been centered on the use of hydrogel forming materials diluted in aqueous solutions or the use of polyesters in combination with diluents and heating platforms that aid in the reduction of their viscosity. The use of diluents, however, modifies the mechanical properties and reduces the shape fidelity of the printed objects and, the use of heating platforms results in vats with heterogeneous temperatures and ink viscosities. Here, we report on the synthesis of a library of methacrylated low molecular weight (<3000 g mol−1) homopolymers ((P(D,L)LA and PCL) and copolymers (P((D,L)LA-co-CL)) of 2- and 3-arms based on (D,L)-lactide and ε-caprolactone. The resulting inks possessed low viscosity that made them printable in the absence of diluents and heating elements. DLP printing of cubical and cylindrical patterns resulted in objects with a higher shape fidelity than their counterparts fabricated using diluents and with printed features on the order of 300 μm. The printed materials were biocompatible and supported the growth of human mesenchymal stem cells (hMSCs). Moreover, the variations in the composition resulted in polymers that enabled the attachment of hMSCs to different extents, leading to the formation of well-adhered cell monolayers or loosely adhered cell aggregates.The authors acknowledge the funding bodies and support through the EMAKIKER grant. S. C.-E. acknowledges the Spanish Ministry of Science and Innovation (MICINN) – State Investigation Agency (AEI) (PID2020-114901RA-I00). S. C.-E. and S. R.-D. acknowledge the Basque Government (PIBA_2022_1_0006). G. L.-J. acknowledges the Basque Government Predoctoral grant PRE_2021_1_0403. S. C.-E. and L. I. acknowledge the Provincial Council of Guipuzcoa. The project that gave rise to these results received the support of a fellowship from the “laCaixa” Foundation (ID100010434). The fellowship code is 117145. S. C.-E. acknowledges funding from the University of the Basque Country UPV/EHU within the framework of Grupos de Investigación (GIU21/033). A. A. acknowledges funding from PID2021-127191OB-I00 and RTI2018-101708-A-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. Grant RYC2018-025502-I funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”

Additive manufacturing of an elastic poly(ester)urethane for cartilage tissue engineering

Although a growing knowledge on the field of tissue engineering of articular cartilage exists, reconstruction or in-vitro growth of functional hyaline tissue still represents an unmet challenge. Despite the simplicity of the tissue in terms of cell population and absence of innervation and vascularization, the outstanding mechanical properties of articular cartilage, which are the result of the specificity of its extra cellular matrix (ECM), are difficult to mimic. Most importantly, controlling the differentiation state or phenotype of chondrocytes, which are responsible of the deposition of this specialized ECM. represents a milestone in the regeneration of native articular cartilage. In this study, we fabricated fused deposition modelled (FDM) scaffolds with different pore sizes and architectures from an elastic and biodegradable poly(ester)urethane (PEU) with mechanical properties that can be modulated by design, and that ranged the elasticity of articular cartilage. Cell culture in additive manufactured 3D scaffolds exceeded the chondrogenic potential of the gold-standard pellet culture. In-vitro cell culture studies demonstrated the intrinsic potential of elastic (PEU) to drive the re-differentiation of de-differentiated chondrocytes when cultured in-vitro, in differentiation or basal media, better than pellet cultures. The formation of neo-tissue was assessed as a high deposition of GAGs and fibrillar collagen II, and a high expression of typical chondrogenic markers. Moreover, the collagen II / collagen I ratio commonly used to evaluate the differentiation state of chondrocytes (ratio > 1 being chondrocytes and, ratio <0 being de-differentiated chondrocytes) was higher than 5. Statement of significance Tissue engineering of articular cartilage requires material scaffolds capable of driving the deposition of a coherent and specific ECM representative of articular cartilage. Materials explored so far account for low mechanical properties (hydrogels), or are too stiff to mimic the elasticity of the native tissue (traditional polyesters). Here, we fabricated 3D fibrous scaffolds via FDM with a biodegradable poly(ester)urethane. The compressive Young's modulus and elastic limit of the scaffolds can be tuned by designed, mimicking those of the native tissue. The designed scaffolds showed an intrinsic potential to drive the formation of a GAG and collagen II rich ECM, and to drive a stable chondrogenic cell phenotype. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved

Bioprinting:From Tissue and Organ Development to <i>in Vitro</i> Models

Bioprinting techniques have been flourishing in the field of biofabrication with pronounced and exponential developments in the past years. Novel biomaterial inks used for the formation of bioinks have been developed, allowing the manufacturing of in vitro models and implants tested preclinically with a certain degree of success. Furthermore, incredible advances in cell biology, namely, in pluripotent stem cells, have also contributed to the latest milestones where more relevant tissues or organ-like constructs with a certain degree of functionality can already be obtained. These incredible strides have been possible with a multitude of multidisciplinary teams around the world, working to make bioprinted tissues and organs more relevant and functional. Yet, there is still a long way to go until these biofabricated constructs will be able to reach the clinics. In this review, we summarize the main bioprinting activities linking them to tissue and organ development and physiology. Most bioprinting approaches focus on mimicking fully matured tissues. Future bioprinting strategies might pursue earlier developmental stages of tissues and organs. The continuous convergence of the experts in the fields of material sciences, cell biology, engineering, and many other disciplines will gradually allow us to overcome the barriers identified on the demanding path toward manufacturing and adoption of tissue and organ replacements.</p

Tailoring biomaterial scaffolds for osteochondral repair

Articular cartilage is a mechanically and structurally complex, lubricious tissue that permits load-bearing and frictionless movement of our joints upon articulation. Unfortunately, cartilage is unable to properly self-heal as a result of acute trauma or damage, resulting in many cases in significant pain, reduction in physical activity and quality of life for the patient. Due to the inability of resident cells to repair damaged osteochondral tissue, researchers have focused on utilizing endogenously or exogenously sourced cells (chondrocytes or tissue-derived mesenchymal stem cells), with or without scaffolds, to encourage the secretion of extracellular matrix (ECM) that replicates this highly anisotropic osteochondral tissue, in which the phenotype of the cells and the composition and orientation of the ECM varies along its depth. Important advances have been achieved towards the development of scaffolds with macroscopically relevant structures, however, articular cartilage and bone tissue contain complex, hierarchical structures that provide cells with biophysical and biochemical cues spanning multiple length scales, presenting researchers with some substantial challenges. This review summarizes the latest advances in mechanical, biochemical and topographical engineering of biomaterials to drive requisite biological responses, such as cell differentiation and matrix deposition, in an effort to achieve functional repair of osteochondral defects

Recent advances and future perspectives on porous materials for biomedical applications

Unformatted postprint version of the accepted articleThe authors gratefully acknowledge financial support from MCIN/AEI/10.13039/501100011033 and FEDER (RTI2018-098951- B-I00, RTI2018-096294-B-C32), IKERBASQUE-Basque Foundation for Science, Basque Government (Elkartek projects KK- 2019/00086 and KK-2020/00010; proyectos de investigacio´ n ba´ sica/aplicada PIBA 2020 1 0056, IT1069-16), Gipuzkoa Provincial Council (2019-CIEN-000075-01). MSO and S.C-E acknowledge support by the Marie-Slodowska-Curie Action under the H2020 framework program, with the projects ‘THERMUCNA’ [896775] and ‘PRIUS-TE’ [845488], respectively. A.B. thanks to the Spanish Research Agency (AEI) for the financial support (PID2019-110239RB-I00 from I+D call and RYC2018-025923-I from RyC program), including FEDER funds; and BBVA foundation (Leonardo Fellowships, IN [21] CBB QUI 0086). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed

Initial teacher training on coordination, leadership and networking with the community

Competencias de coordinación, liderazgo compartido y trabajo en red con la comunidad para el desarrollo de la profesión docente y la mejora escolar. Convocatoria ARMIF-AGAUR (REF. 2015 ARMIF 00041)Las competencias de coordinación, liderazgo compartido y trabajo en red con la comunidad en la formación inicial de los maestros parecen necesarias porque la acción docente en las aulas se tiene que aliar con el liderazgo y la organización óptima del centro educativo. Estamos investigando, a partir de cuestionarios ad hoc, la construcción de estas competencias por parte de los estudiantes del Grado de Educación Infantil de la URV con la colaboración de profesorado y responsables académicos universitarios, y maestros y directores de escuelas donde hacen prácticas. Los resultados muestran que los maestros y directores perciben que, del conjunto de las funciones docentes, la coordinación es la más deficitaria aunque es la más importante, por encima del liderazgo y la relación con el entorno. Sobre la formación inicial de los estudiantes, los maestros y los directores valoran como mejorables las competencias en la resolución de conflictos, análisis de situaciones complejas, gestión del aula y, por último, relación con familias y entidades del entornoSome competences like coordination, distributed leadership and networking with the community seem necessary for initial teacher training because the teaching action in classrooms must be allied with leadership and the optimal organization of schools. We are researching, from questionnaires ad hoc, the building of these competences by university students in the specialty of early childhood education at the URV, with the collaboration of lecturers and academic leaders of the university, and teachers and school principals where university students do their practicum stage. The results show that teachers and principals perceive that, from all the teaching functions, coordination is the less developed although it is the most important, above leadership and the relationship with the socioeducational environment. With regard to the initial training of teachers, in-service teachers and principals consider susceptible to improvement the following competences: conflict resolution, complex situation analysis, classroom management and, finally, relationships with families and entities in the educational contex