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Aquest estudi s'enfoca a millorar les propietats del titani pur de grau 2 per al seu ús en implants ossis. Es va utilitzar la tècnica d'impressió 3D Direct Ink Writing (DIW) per a fabricar mostres, les quals van ser tractades amb plata i calci per a estimular l'osteointegració i millorar la resistència antibacteriana. Posteriorment, es van esterilitzar mitjançant autoclau, radiació gamma i òxid etilè i es van comparar amb mostres que no van ser esterilitzades, per a avaluar l'efecte del procés d'esterilització en les propietats del material. Per a estudiar l'efecte de l'esterilització, es va realitzar una caracterització superficial mitjançant microscòpia electrònica de rastreig (SEM) i espectroscopía de fotoelectrons de raigs X (XPS), assegurant així que es genera l'estructura esperada. Es van realitzar assajos d'alliberament d'ions, proves microbiològiques i assajos d'adhesió cel·lular amb la finalitat d'avaluar la capacitat antimicrobiana i biocompatibilitat de les provetes. Addicionalment s'analitzen i s'estudien les diferents propietats mecàniques del titani, per a així justificar la selecció d'aquest material i del patró Honeycomb (HC). Els resultats van destacar una certa influència de la tècnica d'impressió 3D, però els tractaments termoquímics van ser els que van repercutir més en les propietats de les mostres. Encara que es va observar un cert impacte del mètode d'esterilització, les diferències principals entre les mostres esterilitzades i no esterilitzades estaven relacionades amb processos previs. Se suggereix millorar la precisió de la impressió 3D i realitzar controls mitjançant la tècnica SEM, en diferents etapes dels tractaments termoquímics. Això ajudaria a determinar les diferents propietats i milloraria la qualitat dels empelts ossis., Este estudio se enfoca en mejorar las propiedades del titanio puro de grado 2 para su uso en implantes óseos. Se utilizó la técnica de impresión 3D “Direct Ink Writing” (DIW) para fabricar muestras, las cuales fueron tratadas con plata y calcio para estimular la osteointegración y mejorar la resistencia antibacteriana. Posteriormente, se esterilizaron mediante autoclave, radiación gamma y óxido etileno y se compararon con muestras que no fueron esterilizadas, para evaluar el efecto del proceso de esterilización en las propiedades del material. Para estudiar el efecto de la esterilización, se realizó una caracterización superficial mediante microscopía electrónica de barrido (SEM) y espectroscopía de fotoelectrones de rayos X (XPS), asegurando así que se genera la estructura esperada. Se realizaron ensayos de liberación de iones, pruebas microbiológicas y ensayos de adhesión celular con el fin de evaluar la capacidad antimicrobiana y biocompatibilidad de las probetas. Adicionalmente se analizan y se estudian las distintas propiedades mecánicas del titanio, para así justificar la selección de este material y del patrón Honeycomb (HC). Los resultados destacaron cierta influencia de la técnica de impresión 3D, pero los tratamientos termoquímicos fueron los que repercutieron más en las propiedades de las muestras. Aunque se observó cierto impacto del método de esterilización, las diferencias principales entre las muestras esterilizadas y no esterilizadas estaban relacionadas con procesos previos. Se sugiere mejorar la precisión de la impresión 3D y realizar controles mediante la técnica SEM, en distintas etapas de los tratamientos termoquímicos. Esto ayudaría a determinar las distintas propiedades y mejoraría la calidad de los injertos óseos., This study focuses on improving the properties of pure grade 2 titanium for use in bone implants. The Direct Ink Writing (DIW) 3D printing technique was used to produce samples treated with silver and calcium, to promote osseointegration and improve antibacterial resistance. The samples were then sterilised by autoclaving, gamma irradiation and ethylene oxide and compared with unsterilised samples to evaluate the effect of the sterilisation process on material properties. To investigate the effect of sterilisation, surface characterisation was carried out using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) to ensure that the expected structure was produced. Ion release test, microbiological tests and cell adhesion tests were performed to evaluate the antimicrobial capacity and biocompatibility of the samples. In addition, the different mechanical properties of titanium were analysed and studied to justify the choice of this material and the Honeycomb (HC) pattern. The results showed some influence of the 3D printing technique, but it was the thermochemical treatments that had the biggest effect on the properties of the samples. Although some effect of the sterilisation method was observed, the main differences between sterilised and non-sterilised samples were related to the previous processes. It is suggested that the accuracy of 3D printing be improved, and SEM controls be carried out at different stages of the thermochemical treatments. This would help to determine the different properties and improve the quality of the bone grafts., Aquest estudi s'enfoca a millorar les propietats del titani pur de grau 2 per al seu ús en implants ossis. Es va utilitzar la tècnica d'impressió 3D Direct Ink Writing (DIW) per a fabricar mostres, les quals van ser tractades amb plata i calci per a estimular l'osteointegració i millorar la resistència antibacteriana. Posteriorment, es van esterilitzar mitjançant autoclau, radiació gamma i òxid etilè i es van comparar amb mostres que no van ser esterilitzades, per a avaluar l'efecte del procés d'esterilització en les propietats del material. Per a estudiar l'efecte de l'esterilització, es va realitzar una caracterització superficial mitjançant microscòpia electrònica de rastreig (SEM) i espectroscopía de fotoelectrons de raigs X (XPS), assegurant així que es genera l'estructura esperada. Es van realitzar assajos d'alliberament d'ions, proves microbiològiques i assajos d'adhesió cel·lular amb la finalitat d'avaluar la capacitat antimicrobiana i biocompatibilitat de les provetes. Addicionalment s'analitzen i s'estudien les diferents propietats mecàniques del titani, per a així justificar la selecció d'aquest material i del patró Honeycomb (HC). Els resultats van destacar una certa influència de la tècnica d'impressió 3D, però els tractaments termoquímics van ser els que van repercutir més en les propietats de les mostres. Encara que es va observar un cert impacte del mètode d'esterilització, les diferències principals entre les mostres esterilitzades i no esterilitzades estaven relacionades amb processos previs. Se suggereix millorar la precisió de la impressió 3D i realitzar controls mitjançant la tècnica SEM, en diferents etapes dels tractaments termoquímics. Això ajudaria a determinar les diferents propietats i milloraria la qualitat dels empelts ossis.

Polysaccharides are among the most abundant bioresources on earth and consequently need to play a pivotal role when addressing existential scientific challenges like climate change and the shift from fossil-based to sustainable biobased materials. The Research Roadmap 2040 of the European Polysaccharide Network of Excellence (EPNOE) provides an expert's view on how future research and development strategies need to evolve to fully exploit the vast potential of polysaccharides as renewable bioresources. It is addressed to academic researchers, companies, as well as policymakers and covers five strategic areas that are of great importance in the context of polysaccharide related research: (I) Materials & Engineering, (II) Food & Nutrition, (III) Biomedical Applications, (IV) Chemistry, Biology & Physics, and (V) Skills & Education. Each section summarizes the state of research, identifies challenges that are currently faced, project achievements and developments that are expected in the upcoming 20 years, and finally provides outlines on how future research activities need to evolve.

Bacterial cellulose (BC) is an emerging biopolymer with ever-widening uses in the biomedical field due to its purity, mechanical stability, conformability, moisture control, and biocompatibility. In the wet form, its highly porous nanofibrillar structure and abundant surface hydroxyl groups enable the functionalisation of BC with inorganic nanoparticles (NPs), granting the material additional purposive capabilities. As oxidative stress caused by reactive oxygen species (ROS) negatively affects various cellular structures, the functionalisation of BC with CeO2 NPs, known antioxidants, is pursued in this work to achieve composites capable of minimising inflammation and tissue damage. We report on low-temperature in situ syntheses of CeO2 NPs in BC enabling the formation of BC-CeO2 composites that exhibit self-regenerating antioxidant properties, as verified by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays and studies of the evolution in the CeO2 absorption edge (indicative of the Ce3+ and Ce4+ fractions). X-Ray photoelectron spectroscopy (XPS) further reveals that incorporation of zirconium into the CeO2 lattice leads to a four-fold increase in the Ce3+: Ce4+ ratio, thereby enhancing the composite antioxidant performance as exemplified by BC-Ce0.6Zr0.4O2 recording the highest %DPPH scavenging per unit mass of NPs among the BC-Ce1-xZrxO2 studied systems.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been increasingly used as nanomedicine platforms due to their exceptional magnetic properties, which emerged from their nanoscopic sizes. Recently, SPIONs with a riboflavin (Rf)-citrate ligand were developed and showed increased internalization in breast cancer cells, with exceptional properties as T2 contrast agents for magnetic resonance imaging (MRI). The interactions of the Rf-coated SPIONs with proteins from fetal bovine serum (FBS) were previously characterized to understand how the nanoparticles will interact with biomolecules. To closer mimic the human biological environments, human serum (HS) has been suggested as a better model. Therefore, in this work, protein coronas of bare, citrate-coated, and Rf-coated SPIONs formed with HS were studied by proteomic analysis to identify and quantify the nanoparticle-protein interaction. The results were compared with the FBS-derived coronas to understand the differences in the protein corona formation from different serum origins. Furthermore, the interactions of the SPIONs with riboflavin carrier protein (RCP), which is a target protein for the Rf-SPIONs, were also studied. The overall physical properties of the corona proteins were similar between the FBS and HS groups, but some specific homologous proteins interacted differently. The RCP was found to bind more to the citrate-coated SPIONs than the Rf-coated one. The outcome could be explained by molecular dynamics simulation, where the orientation of the Rf ligand did not favor the binding with RCP. The simulation results also showed the influence of surface hydrophilicity of the SPIONs on the RCP interaction. The combined data from proteomic and simulation analyses suggested a way to improve the Rf ligand to enhance the interaction with RCP and reduce the interactions with the serum proteins, which could enhance the specific cellular interactions and improve the Rf-SPIONs as MRI contrast agents for breast ca

Sepsis is a syndromic response to infection and is frequently a final common pathway to death from many infectious diseases worldwide. The complexity and high heterogeneity of sepsis hinder the possibility to treat all patients with the same protocol, requiring personalized management. The versatility of extracellular vesicles (EVs) and their contribution to sepsis progression bring along promises for one-to-one tailoring sepsis treatment and diagnosis. In this article, we critically review the endogenous role of EVs in sepsis progression and how current advancements have improved EVs-based therapies toward their translational future clinical application, with innovative strategies to enhance EVs effect. More complex approaches, including hybrid and fully synthetic nanocarriers that mimic EVs, are also discussed. Several pre-clinical and clinical studies are examined through the review to offer a general outlook of the current and future perspectives of EV-based sepsis diagnosis and treatment.

There is a growing interest in developing natural hydrogel-based scaffolds to culture cells in a three-dimensional (3D) millieu that better mimics the in vivo cells' microenvironment. A promising approach is to use hydrogels from animal tissues, such as decellularized extracellular matrices; however, they usually exhibit suboptimal mechanical properties compared to native tissue and their composition with hundreds of different protein complicates to elucidate which stimulus triggers cell's responses. As simpler scaffolds, type I collagen hydrogels are used to study cell behavior in mechanobiology even though they are also softer than native tissues. In this work, type I collagen is mixed with bacterial nanocellulose fibers (BCf) to develop reinforced scaffolds with mechanical properties suitable for 3D cell culture. BCf were produced from blended pellicles biosynthesized from Komagataeibacter xylinus. Then, BCf were mixed with concentrated collagen from rat-tail tendons to form composite hydrogels. Confocal laser scanning microscopy and scanning electron microscopy images confirmed the homogeneous macro- and microdistribution of both natural polymers. Porosity analysis confirmed that BCf do not disrupt the scaffold structure. Tensile strength and rheology measurements demonstrated the reinforcement action of BCf (43% increased stiffness) compared to the collagen hydrogel while maintaining the same viscoelastic response. Additionally, this reinforcement of collagen hydrogels with BCf offers the possibility to mix cells before gelation and then proceed to the culture of the 3D cell scaffolds. We obtained scaffolds with human bone marrow-derived mesenchymal stromal cells or human fibroblasts within the composite hydrogels, allowing a homogeneous 3D viable culture for at least 7 days. A smaller surface shrinkage in the reinforced hydrogels compared to type I collagen hydrogels confirmed the strengthening of the composite hydrogels. These collagen hydrogels reinforced wi

Breast cancer accounts for up to 10% of the newly diagnosed cancer cases worldwide, making it the most common cancer found in women. The use of superparamagnetic iron oxide nanoparticles (SPIONs) has been beneficial in the advancement of contrast agents and magnetic hyperthermia (MH) for the diagnosis and treatment of cancers. To achieve delivery of SPIONs to cancer cells, surface functionalization with specific ligands are required. Riboflavin carrier protein (RCP) has been identified as an alternative target for breast cancer cells. Here, we report a novel riboflavin (Rf)-based ligand that provides SPIONs with enhanced colloidal stability and high uptake potential in breast cancer cells. This is achieved by synthesizing an Rf-citrate ligand. The ligand was tested in a multicore SPION system, and affinity to RCP was assessed by isothermal titration calorimetry which showed a specific, entropy-driven binding. MRI and MH responses of the coated Rf-SPIONs were tested to evaluate the suitability of this system as a theranostic platform. Finally, interaction of the Rf-SPIONs with breast cancer cells was evaluated by in vitro cellular uptake in MCF-7 breast cancer cells. The overall characterization of the Rf-SPIONs highlighted the excellent performance of this platform for theranostic applications in breast cancer.

Nearly four million yearly deaths can be attributed to respiratory diseases, prompting a huge worldwide health emergency. Additionally, the COVID-19 pandemic’s death toll has surpassed six million, significantly increasing respiratory disease morbidity and mortality rates. Despite recent advances, it is still challenging for many drugs to be homogeneously distributed throughout the lungs, and specifically to reach the lower respiratory tract with an accurate sustained dose and minimal systemic side effects. Engineered nanocarriers can provide increased therapeutic efficacy while lessening potential biochemical adverse reactions. Poly(lactic-co-glycolic acid) (PLGA), a biodegradable polymer, has attracted significant interest as an inhalable drug delivery system. However, the influence of the nanocarrier surface charge and its intratracheal instillation has not been addressed so far. In this study, we fabricated red fluorescent PLGA nanocapsules (NCs)—Cy5/PLGA—with either positive (Cy5/PLGA+) or negative surface charge (Cy5/PLGA-). We report here on their excellent colloidal stability in culture and biological media, and after cryo-storage. Their lack of cytotoxicity in two relevant lung cell types, even for concentrations as high as 10 mg/mL, is also reported. More importantly, differences in the NCs’ cell uptake rates and internalization capacity were identified. The uptake of the anionic system was faster and in much higher amounts—10-fold and 2.5-fold in macrophages and epithelial alveolar cells, respectively. The in vivo study demonstrated that anionic PLGA NCs were retained in all lung lobules after 1 h of being intratracheally instilled, and were found to accumulate in lung macrophages after 24 h, making those nanocarriers especially suitable as a pulmonary immunomodulatory delivery system with a marked translational character.

Noble metal decoration of wideband gap semiconductors enables the excitation of surface plasmons in the visible range that upon relaxation generate hot carriers used for catalysis. However, this strategy leads to photocatalytic conversion efficiencies that are still low. Here, a light-trapping scheme is used to amplify the light-harvesting efficiency of the TiO2 semiconductor beyond the UV region by coupling a 2D-photonic crystal to Au decorated titania. This approach is easily scalable using soft nanoimprinting lithography to prepare Au/TiO2 2D-photonic photocatalysts. In a first process, gold nanoparticles (Au NPs) are in situ infiltrated in the superficial 50 nm of a mesoporous titania (mTiO2) scaffold patterned with the photonic structure, while in a second one 2D-photonic crystals with a homogeneous volume distribution of the Au colloids are achieved. The dependence of the optical properties of the photonic crystals on the lattice parameter, geometry, and metal loading is presented through extinction measurements and analyzed through simulations. The improved photocatalytic performance of the substrates is tested for hydrogen production where a maximum of 8.5 mmol gcat−1 h−1 of H2 is recorded and attributed to photonic–plasmonic effects. These results may open new avenues in solar harvesting for hydrogen production using photonic crystals as photocatalysts.

Introduction: Case-Based Learning (CBL) teaching methodology is an active learning methodology that generates a higher level of student participation and significant learning. The aim of this study was to analyse and compare a CBL activity using deductive reasoning (analyse and extract theoretical concepts in a case provided for this purpose) and a CBL activity using inductive reasoning (create a case by implicitly introducing theoretical concepts) in terms of academic performance and student satisfaction, as well as to analyse the relationship of the latter with the perception of self-efficacy. Methodology: A descriptive cross-sectional study was developed. 111 students performed both CBL activities (deductive and inductive). Each learning activity dealt with theoretical contents of group psychology. The variables collected were: activity grade, satisfaction with each activity, theoretical exam grade and perception of self-efficacy. A descriptive, correlational, and comparative analysis was conducted using T-Student of related samples. Results: The gradesfor the inductive CBL activity were significantly higher than those for the deductive CBL activity (p=0.042). The students ́ level of satisfaction in the item “helps to think critically” was evaluated more favourably for the deductive CBL activity (p=0.029). The relationship between the grade of the inductive CBL activity and that obtained in the theoretical exam was significant. There was no correlation between any of the activities and the perceived self-efficacy of the students. Conclusions: The CBL activity with inductive reasoning is more effective to achieve academic performance and the satisfaction with the activities evaluated by the students is high.

Nanostructured scaffolds based on cellulose with advanced performances and personalized morphologies for bone tissue engineering are under technological development. 3D-printing and supercritical carbon dioxide (scCO2) technologies are innovative processing strategies that, when combined, allow the precise fabrication of highly porous aerogel scaffolds. Novel sterile cellulose-in-cellulose aerogels decorated with superparamagnetic iron oxide nanoparticles (SPIONs) are synthesized in this work by an integrated technological platform based on 3D-printing and scCO2. Methylcellulose (MC) and bacterial nanocellulose (BC) are two versatile cellulosic polysaccharides with remarkable physicochemical and biological performances, whereas SPIONs are commonly used to functionalize biomaterials aimed at tissue engineering. Aerogels with hierarchical porosity and high structural resolution were obtained according to nitrogen adsorption–desorption analysis, confocal, scanning and transmission microscopies (SEM and TEM). The magnetic properties of SPIONs-doped aerogels confirmed the correct functionalization of the nanostructures. Finally, NIH/3T3 fibroblast cell viability, hemocompatibility with human blood and safety tests (in ovo with HET-CAM and in vivo with Artemia salina) indicate the biocompatibility of the cellulose-in-cellulose aerogels. Graphical abstract: [Figure not available: see fulltext.].

Actuated structures are becoming relevant in medical fields; however, they call for flexible/soft-base materials that comply with biological tissues and can be synthesized in simple fabrication steps. In this work, we extend the palette of techniques to afford soft, actuable spherical structures taking advantage of the biosynthesis process of bacterial cellulose. Bacterial cellulose spheres (BCS) with localized magnetic nanoparticles (NPs) have been biosynthesized using two different one-pot processes: in agitation and on hydrophobic surface-supported static culture, achieving core-shell or hollow spheres, respectively. Magnetic actuability is conferred by superparamagnetic iron oxide NPs (SPIONs), and their location within the structure was finely tuned with high precision. The size, structure, flexibility and magnetic response of the spheres have been characterized. In addition, the versatility of the methodology allows us to produce actuated spherical structures adding other NPs (Au and Pt) in specific locations, creating Janus structures. The combination of Pt NPs and SPIONs provides moving composite structures driven both by a magnetic field and a H2O2 oxidation reaction. Janus Pt/SPIONs increased by five times the directionality and movement of these structures in comparison to the controls.