Flipped classroom evaluation using kahott and moodle in the undergraduate teaching lab

Comunicación presentada en EDULEARN 2018, 10th International Conference on Education and New Learning Technologies (July 2-4, 2018, Palma, Mallorca, Spain).This article analyzes the implementation of a flipped classroom methodology in the undergraduate teaching labs of engineering degrees. The methodology is focused on providing the students, before the lab session, with audio-visual resources that cover the theoretical background and explanations needed to follow the session. At the beginning of each lab session, the preparatory work performed by the students is evaluated with an on-line test, which was performed using Kahoot and Moodle resources and has an impact on the mark of the session. This methodology is helpful in the sense that eliminates the frequently required theoretical introduction, allowing devoting more time to the experimental part. On the other hand, it provides an immediate information of the degree of prior knowledge gained by the students, so the weaker aspects can be reinforced during the lab session. An analysis of the advantages and disadvantages found for the two on-line resources employed, in conjunction with the impact produced on the students by the methodology is presented. Moodle was found to show greater seriousness and more versatility to introduce the test questions. However, the use of Kahoot was preferred by the students, since it creates a more relaxed lab atmosphere, which was also very useful to increase the participation of some students who were unmotivated. The students recognized that the methodology helped to better follow the lab sessions and improved the quality of their lab reports, which are the items used for their evaluation

Design of nanostructured siloxane-gelatin coatings: Immobilization strategies and dissolution properties

Owing to the outstanding service life of metallic prostheses, a substantial effort has been put into their surface modification to improve biocompatibility and reduce metallic ion diffusion. To satisfy these requirements, the coating materials obtained using the sol-gel method, with its wide range of tuning properties, have been extensively explored. The well-known biocompatibility of these materials makes them good candidates for different biomedical applications. We designed a series of siloxane-gelatin hybrids to be used as coatings for metallic implants or in controlled delivery systems. Two different matrixes were designed based on methyltrimethoxysilane (MTMOS), tetraethoxysilane (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) alkoxysilane precursors. In one hybrid coating gelatin was physically entrapped and in the other it was linked to the siloxane network by covalent bonds. Synthesis parameters were established by studying the sol-gel reaction using 29Si nuclear magnetic resonance (29Si NMR), which also allowed quantification of the network connectivity. Dissolution and degradation studies showed the effectiveness of GPTMS as a covalent coupling agent between the silica and gelatin phases; it increased the stability of the coatings in aqueous media. The aim of this study was to design a set of hybrid materials with highly tailorable properties, suitable for their potential biomedical application

Breast cancer cell line MCF7 escapes from G1/S arrest induced by proteasome inhibition through a GSK-3β dependent mechanism

Targeting the ubiquitin proteasome pathway has emerged as a rational approach in the treatment of human cancers. Autophagy has been described as a cytoprotective mechanism to increase tumor cell survival under stress conditions. Here, we have focused on the role of proteasome inhibition in cell cycle progression and the role of autophagy in the proliferation recovery. The study was performed in the breast cancer cell line MCF7 compared to the normal mammary cell line MCF10A. We found that the proteasome inhibitor MG132 induced G1/S arrest in MCF10A, but G2/M arrest in MCF7 cells. The effect of MG132 on MCF7 was reproduced on MCF10A cells in the presence of the glycogen synthase kinase 3β (GSK-3β) inhibitor VII. Similarly, MCF7 cells overexpressing constitutively active GSK-3β behaved like MCF10A cells. On the other hand, MCF10A cells remained arrested after MG132 removal while MCF7 recovered the proliferative capacity. Importantly, this recovery was abolished in the presence of the autophagy inhibitor 3-methyladenine (3-MA). Thus, our results support the relevance of GSK-3β and autophagy as two targets for controlling cell cycle progression and proliferative capacity in MCF7, highlighting the co-treatment of breast cancer cells with 3-MA to synergize the effect of the proteasome inhibition

Control of the degradation of silica sol-gel hybrid coatings for metal implants prepared by the triple combination of alkoxysilanes

Hybrid materials obtained by sol-gel process are able to degrade and release Si compounds that are useful in regenerative medicine due to their osteoinductive properties. The present work studies the behavior of new organic-inorganic sol-gel coatings based on triple mixtures of alkoxysilanes in different molar ratios. The precursors employed are methyl-trimethoxysilane (MTMOS), 3-glycidoxypropyl-trimethoxysilane (GPTMS) and tetraethyl-orthosilicate (TEOS). After optimization of the synthesis conditions, the coatings were characterized using 29Si nuclear magnetic resonance (29Si-MNR), Fourier transform infrared spectrometry (FT-IR), contact angle measurements, hydrolytic degradation assays, electrochemical impedance spectroscopy (EIS) and mechanical profilometry. The degradation and EIS results show that by controlling the amount of TEOS precursor in the coating it is possible to tune its degradation by hydrolysis, while keeping properties such as wettability at their optimum values for biomaterials application. The corrosion properties of the new coatings were also evaluated when applied to stainless steel substrate. The coatings showed an improvement of the anticorrosive properties of the steel which is important to protect the metal implants at the early stages of the regeneration process.The financial support of MAT2014-51918-C2-2-R, P11B2014-19 and Plan de Promoción de la Investigación from the Universitat Jaume I (Predoc/2014/25) is gratefully acknowledged. J. García-Cañadas acknowledge financial support from Ramón y Cajal programme (RYC-2013-13970). The experimental support of Raquel Oliver Valls and José Ortega Herreros is also acknowledged

Proteomic Analysis of Mesenchymal Stem Cells and Monocyte Co-Cultures Exposed to a Bioactive Silica-Based Sol–Gel Coating

New methodologies capable of extensively analyzing the cell-material interactions are necessary to improve current in vitro characterization methods, and proteomics is a viable alternative. Also, many studies are focused on monocultures, even though co-cultures model better the natural tissue. For instance, human mesenchymal stem cells (MSCs) modulate immune responses and promote bone repair through interaction with other cell types. Here, label-free liquid chromatography tandem mass spectroscopy proteomic methods were applied for the first time to characterize HUCPV (MSC) and CD14+ monocytes co-cultures exposed to a bioactive sol–gel coating (MT). PANTHER, DAVID, and STRING were employed for data integration. Fluorescence microscopy, enzyme-linked immunosorbent assay, and ALP activity were measured for further characterization. Regarding the HUCPV response, MT mainly affected cell adhesion by decreasing integrins, RHOC, and CAD13 expression. In contrast, MT augmented CD14+ cell areas and integrins, Rho family GTPases, actins, myosins, and 14-3-3 expression. Also, anti-inflammatory (APOE, LEG9, LEG3, and LEG1) and antioxidant (peroxiredoxins, GSTO1, GPX1, GSHR, CATA, and SODM) proteins were overexpressed. On co-cultures, collagens (CO5A1, CO3A1, CO6A1, CO6A2, CO1A2, CO1A1, and CO6A3), cell adhesion, and pro-inflammatory proteins were downregulated. Thus, cell adhesion appears to be mainly regulated by the material, while inflammation is impacted by both cellular cross-talk and the material. Altogether, we conclude that applied proteomic approaches show its potential in biomaterial characterization, even in complex systems.This work was supported by MINECO [MAT2017-86043-R; RTC-2017-6147-1], Generalitat Valenciana [GRISOLIAP/2018/091, BEFPI/2021/043, PROMETEO/2020/069], Universitat Jaume I [UJI-B2017-37], and the University of the Basque Country [GIU18/189]. Andreia Cerqueira was supported by the Margarita Salas postdoctoral contract MGS/2022/10 (UP2022-024) financed by the European Union-NextGenerationEU. The University Medical Centre Hamburg-Eppendorf (Hamburg, Germany) and the Clinics for Gynecology AGAPLESION BETHESDA Hospital provided the blood and tissue for cell isolation. The authors would like to thank Raquel Oliver, Jose Ortega, Iraide Escobés, and Anke Borkam-Schuster for their valuable technical assistance and Antonio Coso (GMI-Ilerimplant) for producing the titanium discs

Proteomic analysis of silica hybrid sol-gel coatings: a potential tool for predicting the biocompatibility of implants in vivo

The interactions of implanted biomaterials with the host organism determine the success or failure of an implantation. Normally, their biocompatibility is assessed using in vitro tests. Unfortunately, in vitro and in vivo results are not always concordant; new, effective methods of biomaterial characterisation are urgently needed to predict the in vivo outcome. As the first layer of proteins adsorbed onto the biomaterial surfaces might condition the host response, mass spectrometry analysis was performed to characterise these proteins. Four distinct hybrid sol-gel biomaterials were tested. The in vitro results were similar for all the materials examined here. However, in vivo, the materials behaved differently. Six of the 171 adsorbed proteins were significantly more abundant on the materials with weak biocompatibility; these proteins are associated with the complement pathway. Thus, protein analysis might be a suitable tool to predict the in vivo outcomes of implantations using newly formulated biomaterials

Development and characterisation of strontium-doped sol-gel coatings to optimise the initial bone regeneration processes

Strontium plays an important role in bone regeneration; it promotes the differentiation and maturation of osteoblasts and inhibits the activity of osteoclasts. Our principal objective in this study was to formulate new organic-inorganic hybrid sol-gel coatings applied to titanium discs. These coatings were functionalised with different amounts of SrCl2 and examined using in vitro tests and proteomics. The chemical and morphological characteristics of obtained coatings were scrutinised. The in vitro evaluation using the MC3T3-E1 osteoblasts and RAW264.7 macrophages showed the osteogenic and anti-inflammatory effects of strontium doping. The proteomic assay identified 111 different proteins adhering to the coatings. Six of these proteins reduced their adhesion affinity as a result of Sr-doping, whereas 40 showed increased affinity. Moreover, the proteomic analysis revealed osteogenic and anti-inflammatory properties of these biomaterials. The analysis also showed increased adhesion of proteins related to the coagulation system. We can conclude that proteomic methods are invaluable in developing new biomaterials and represent an important tool for predicting the biocompatibility of dental implants

Osteointegración de implantes de titanio con superficies activas. Un estudio proteómico

Titanium is a biomaterial largely used on dental implant manufacturing. However, as a consequence of its intrinsically low bioactivity, the development of distinct superficial treatments in order to enhance its osseointegration properties is being studied. In this sense, the use of titanium implants with a higher level of roughness has been broadened, recurring to the application of sand-blasted acid-etched surface treatments. In this article, a study of two distinct titanium surface treatments has been carried out, regarding the physico-chemical properties (roughness, hydrophilicity and chemical composition) of each, as well as the pattern of adhered proteins onto each surface (proteomic study). Hence, mass spectrometry analysis allowed the detection of 2 18 d istinct a dsorbed p roteins, being 37 of those related to bone regenerative processes and dental implant integration. Moreover, using differential quantification between associated proteins, comparing surfaces, it was observable a greater affinity of APOE, ANT3 and PROC proteins to the treated surface, directly linked to the bone regenerative process. On the other hand, the treated surface displays lower affinity of CO3 protein. The variations between the adsorbed protein profiles could be an explanation for distinct in vivo outcomes.El titanio es un biomaterial ampliamente empleado en la fabricación de implantes dentales, sin embargo, como consecuencia de su baja bioactividad se han desarrollado distintos tratamientos superficiales buscando una mejora en su capacidad de osteintegración. De esta forma, se ha extendido el uso de implantes de titanio con un mayor grado de rugosidad gracias a la aplicación de un tratamiento de granallado, al que le sigue un tratamiento de ataque ácido. En este artículo se ha llevado a cabo un estudio de discos de titanio con dos tipos de superficie: sin tratamiento alguno y con tratamiento de granallado más ataque ácido. El estudio reveló diferencias físico-químicas (rugosidad, hidrofilia y composición química) tras la aplicación del tratamiento superficial, pero también en cuanto al perfil de proteínas adheridas a cada superficie (estudio proteómico). Así, la espectrometría de masas permitió la caracterización de las proteínas adsorbidas en ambos tipos de superficies. El análisis permitió la identificación de 218 proteínas distintas, pudiendo relacionar 37 de ellas con el proceso de regeneración ósea y en consecuencia con la osteointegración de un implante dental. Además, tras la cuantificación diferencial entre proteínas asociadas, antes y después de aplicar el tratamiento superficial mencionado, se observó que tras su aplicación se producía un aumento en la afinidad de las proteínas APOE, ANT3 y PROC, directamente relacionadas con el proceso de regeneración ósea. Por el contrario, la proteína CO3 se adhería a esta superficie en menor proporción. Estas variaciones de los perfiles de proteínas podrían explicar la diferencia encontrada en la respuesta de las distintas superficies al ser caracterizadas en cuanto a su comportamiento in vivo

Sol-gel coatings for metallic prosthesis from methyl-modified alkoxysilanes: balance between protection and bioactivation

The reported osteogenic properties of the hybrid silica sol-gel materials make these compositions perfect candidates for bone tissue engineering applications. The aim of this study was the synthesis and characterisation of hybrid silica coatings, obtained using mixtures of tetraethyl orthosilicate (TEOS) and three different methyl-modified alkoxysilanes: trimethoxymethylsilane (MTMS), dimethyldiethoxysilane (DMDES) or polydimethylsiloxane (PDMS). A comparison of the properties of these materials can reveal the best candidate for the coatings on metallic prostheses. After optimising the synthesis parameters, the developed coatings were characterised using Fourier transform infrared spectrometry (FT-IR), 1H and 29Si solid-state nuclear magnetic resonance (1H-NMR and 29Si-MNR), cross-cut tests, scanning electron microscopy (SEM), contact angle measurements, optical profilometry, hydrolytic degradation tests and electrochemical corrosion analysis. Homogeneous and well-adhering coatings were obtained using the three methyl-modified reagents. However, different degrees of protection against corrosion, different hydrophilicity and varying degradation kinetics were observed for different precursors. The MTMS-based coating showed the highest hydrophilicity and degradation kinetics; these properties can be associated with increased bioactivity (Si release). In contrast, the PDMS and DMDES-based coatings showed augmented resistance to corrosion and lower permeability to water and, consequently, improved protection of metallic surfaces. From the physicochemical point of view, all these materials displayed interesting characteristics, relevant for coatings to be used in biomedical applications

Characterization of serum proteins attached to distinct sol–gel hybrid surfaces

The success of a dental implant depends on its osseointegration, an important feature of the implant biocompatibility. In this study, two distinct sol–gel hybrid coating formulations [50% methyltrimethoxysilane: 50% 3-glycidoxypropyl-trimethoxysilane (50M50G) and 70% methyltrimethoxysilane with 30% tetraethyl orthosilicate (70M30T)] were applied onto titanium implants. To evaluate their osseointegration, in vitro and in vivo assays were performed. Cell proliferation and differentiation in vitro did not show any differences between the coatings. However, four and eight weeks after in vivo implantation, the fibrous capsule area surrounding 50M50G-implant was 10 and 4 times, respectively, bigger than the area of connective tissue surrounding the 70M30T treated implant. Thus, the in vitro results gave no prediction or explanation for the 50M50G-implant failure in vivo. We hypothesized that the first protein layer adhered to the surface may have direct implication in implant osseointegration, and perhaps correlate with the in vivo outcome. Human serum was used for adsorption analysis on the biomaterials, the first layer of serum proteins adhered to the implant surface was analyzed by proteomic analysis, using mass spectrometry (LC-MS/MS). From the 171 proteins identified; 30 proteins were significantly enriched on the 50M50G implant surface. This group comprised numerous proteins of the immune complement system, including several subcomponents of the C1 complement, complement factor H, C4b-binding protein alpha chain, complement C5 and C-reactive protein. This result suggests that these proteins enriched in 50M50G surface might trigger the cascade leading to the formation of the fibrous capsule observed. The implications of these results could open up future possibilities to predict the biocompatibility problems in vivo