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Coronavirus disease (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with systemic organ damage in the most severe forms. Long-term complications of SARS-CoV-2 appear to be restricted to severe presentations of COVID-19, but many patients with persistent symptoms have never been hospitalized. Post-acute sequelae of COVID-19 (PASC) represents a heterogeneous group of symptoms characterized by cardiovascular, general, respiratory, and neuropsychiatric sequelae. The pace of evidence acquisition with PASC has been rapid, but the mechanisms behind it are complex and not yet fully understood. In particular, exercise intolerance shares some features with other classic respiratory and cardiac disorders. However, cardiopulmonary exercise testing (CPET) provides a comprehensive assessment and can unmask the pathophysiological mechanism behind exercise intolerance in gray-zone PASC. This mini-review explores the utility of CPET and aims to provide a comprehensive assessment of PASC by summarizing the current evidence.

Aims Timing surgery in chronic aortic regurgitation (AR) relies mostly on echocardiography. However, cardiac magnetic resonance (CMR) may be more accurate for quantifying regurgitation and left ventricular (LV) remodelling. We aimed to compare the technical and clinical efficacies of echocardiography and CMR to account for the severity of the disease, the degree of LV remodelling, and predict AR-related outcomes. Methods and results We studied 263 consecutive patients with isolated AR undergoing echocardiography and CMR. After a median follow-up of 33 months, 76 out of 197 initially asymptomatic patients reached the primary endpoint of AR-related events: 6 patients (3%) were admitted for heart failure, and 70 (36%) underwent surgery. Adjusted survival models based on CMR improved the predictions of the primary endpoint based on echocardiography: R2 = 0.37 vs. 0.22, χ2 = 97 vs. 49 (P 37%) and LV end-diastolic volume (236 mL) adequately stratified patients with normal EF. The agreement between techniques for grading AR severity and assessing LV dilatation was poor, and CMR showed better reproducibility. Conclusions CMR improves the clinical efficacy of ultrasound for predicting outcomes of patients with AR. This is due to its better reproducibility and accuracy for grading the severity of the disease and its impact on the LV. Regurgitant fraction, LV ejection fraction, and end-diastolic volume obtained by CMR most adequately predict AR-related events.

Over the past 13 years bone marrow-derived mononuclear cells (BM-MNCs) have been widely investigated for clinical efficacy in patients following acute myocardial infarction (AMI). These early phase II trials have used various surrogate markers to judge efficacy and, although promising, the results have been inconsistent. The phase III BAMI trial has therefore been designed to demonstrate that intracoronary infusion of BM-MNCs is safe and will significantly reduce the time to first occurrence of all-cause death in patients with reduced left ventricular ejection fraction after successful reperfusion for ST-elevation AMI (powered with the aim of detecting a 25% reduction in all-cause mortality). This is a multinational, multicentre, randomized, open-label, controlled, parallel-group phase III study aiming to enrol approximately 3000 patients in 11 European countries with at least 17 sites. Eligible patients who have impaired left ventricular ejection (≤45%) following successful reperfusion for AMI will be randomized to treatment or control group in a 1:1 ratio. The treatment group will receive intracoronary infusion of BM-MNCs 2-8 days after successful reperfusion for AMI added on top of optimal standard of care. The control group will receive optimal standard of care. The primary endpoint is time from randomization to all-cause death. The BAMI trial is pivotal and the largest trial to date of BM-MNCs in patients with impaired left ventricular function following AMI. The aim of the trial is to provide a definitive answer as to whether BM-MNCs reduce all-cause mortality in this group of patients.

Introducción/objetivos: esta iniciativa surge de la puesta en común de experiencias docentes en las I Jornadas de Innovación Docente en Medicina y Cirugía Animal (Córdoba, 2011). Allí se presentaron algunas actividades que utilizan el éxito de metodologías basadas en concursos y competiciones, que consiguen que los alumnos las adopten fácilmente como métodos de aprendizaje.La actividad propuesta se basa en el popular juego TRIVIAL™ en el que equipos de alumnos contestan cuestiones de una batería de preguntas sobre veterinaria equina. Las preguntas están agrupadas por sistemas/especialidades.Se persigue crear un sistema de aprendizaje y autoevaluación formativa, que permita la evaluación de conocimientos adaptados al nivel de los alumnos de S~ del Grado en Veterinaria. Además de autoevaluar sus propios conocimientos sin la presión de un examen formal, el alumno practica la dinámica de grupo. La competitividad generada entre equipos estimula el trabajo individual y de grupo (...)

This work describes the influence of surface pretreatments over the nucleation and growth of an apatite layer, formed by a biomimetic process, on which a bioactive glass is used as a precursor of the calcium-phosphate (Ca-P) formation on the materials surface. SEVA-C, a corn starch-based biodegradable blend, was used as substrate. The surfaces were pretreated during various periods by: (i) physical methods, namely ultraviolet radiation (u.v.), and over exposure to ethylene oxide sterilization (EtO); and (ii) chemical methods, namely potassium hydroxide (KOH) and acetic anhydride (CH3CO)2 etchings. The surface modifications, performed before the production of the biomimetic coatings, resulted in a faster formation of Ca-P nuclei during the first stages of SBF immersion, particularly in the case of the KOH etching. In this case, it was possible to observe a decrease in the average surface roughness, as measured by laser profilometry, and an increase of the hydrophilicity of the material, which was evident from a clear increment in the water-uptake ability and quantified by contact angle measurements. With this treatment it was possible not only to reduce the induction period for the formation of a well defined and dense apatite-like layer, as observed by scanning electron microscopy (SEM), but also to improve the adhesion of the Ca-P layer to the substrate, as confirmed by the adhesion strength tests. For all the studied pre-treatments, the composition of the films, analyzed by energy dispersive spectroscopy (EDS) and identified by thin-film X-ray diffraction (TF-XRD), seems to be very similar to that of human bone apatites.

The synthesis and application as resorbable coatings of vascular grafts of a new polyacrylic derivative of Triflusal (2-acetyloxy-4-trifluoromethyl)benzoic acid, a commercial drug with antithrombogenic properties, are described. The high-molecular-weight polyacrylic system is rather stable in physiological conditions and provides a chemical support for the slow release of the pharmacologically active compound, Triflusal, or its main metabolite (2-hydroxy-4-trifluoromethyl)benzoic acid (HTB). Experiments of deposition and retention of platelets in static basal conditions using plasma-rich medium from blood of sheep, seem to indicate that the polymeric coating of the polyacrylic derivative of Triflusal improves the antiaggregating character for platelets of the surface of small-diameter vascular grafts without the application of other antithrombogenic drugs.

Background: All support and training is aimed at facilitating patient's integration in guideline development groups (GDG). There are hardly any strategies to help healthcare professionals to incorporate patients' participation in the development of Clinical Practice Guidelines (CPGs). [for full text, please go to the a.m. URL], G-I-N Conference 2012

Nasolacrimal duct obstruction is a common problem. A Song stent is a useful and simple treatment with low morbidity. However, the success rate is limited, especially in long-term follow-up. The aim of the present study is to determine the presence of biofilms in failing nasolacrimal stents.Thirty-three polyurethane nasolacrimal stents were implanted between January 2006 and December 2007 using Song's technique. Patients were followed for a mean of 21.5 months (range 11-30 months). Removed nasolacrimal stents were preserved in saline and examined using environmental scanning electron microscopy (ESEM).Eighteen nasolacrimal stents were removed because of the failure of the device (follow-up range 11-30 months). Seven stents were recovered for this study. Biofilms were identified in all the specimens studied. Five prostheses showed occlusion caused by mucus or granulation tissue.Biofilm colonisation of nasolacrimal stents could play a major role in prosthetic failure leading to stent occlusion. Mucus, granulation tissue and irregularities of the biomaterial are factors that facilitate biofilm colonisation. Non-stick material for newly developed stents or drugs capable of destroying the polysaccharide matrix should be considered as future therapeutic options.

Objetivo: El objetivo de la I Conferencia Española de Consenso sobre el Injerto Óseo Sinusal era intentar llegar a puntos de acuerdo sobre las principales controversias de esta técnica, aplicada de forma muy variada y con el empleo de materiales muy diversos, y conseguir plasmar los mismos en un documento resumen consensuado por todos los autores. Material y método: Durante los días 17 y 18 de octubre de 2008 se celebró en Oviedo la citada conferencia, auspiciada por la Sociedad Española de Cirugía Oral y Maxilofacial. En ella se dieron cita un total de 50 ponentes de reconocido prestigio nacional e internacional que repasaron en 6 mesas de trabajo las principales controversias sobre los injertos óseos sinusales. Tras las conferencias de los ponentes, los moderadores establecían las principales conclusiones de cada mesa y se abría un turno de debate donde participaban todos los asistentes. Resultado: Este documento y sus conclusiones emanan de las presentaciones realizadas por los ponentes y de las deliberaciones y acuerdos de cada mesa de trabajo. Ambos han sido aprobados tras varias correcciones por todos los autores antes de ser enviados para su publicación. Además, han obtenido el reconocimiento científico oficial de la Sociedad Española de Cirugía Oral y Maxilofacial y deben servir como base para futuros estudios y reuniones científicas. Conclusiones: El objetivo fundamental cuando se realiza un injerto óseo sinusal es la formación de hueso vital en el seno maxilar, para conseguir la supervivencia a largo plazo de los implantes tras su carga protésica. Para ello, la técnica y la secuencia de tratamiento deben orientarse a conseguir resultados predecibles y estables en el tiempo, aunque esto suponga un mayor tiempo de espera hasta la colocación de la prótesis. La estabilidad inicial del implante es el factor clave para la osteointegración y debe ser el principal criterio para indicar implantes simultáneos o diferidos en el seno maxilar. Objective: The objectives of the first Spanish Consensus Conference on Sinus Bone Graft were trying to reach agreements points on the major controversies of this technique, and translate them in a summary document. Material and method: During the 17th and 18th of October of 2008 took place in Oviedo (Spain) the Conference, sponsored by the Spanish Society of Oral and Maxillofacial Surgery. There, 50 national and international speakers reviewed in 6 workshops the major controversies of sinus bone grafts. Following the conferences, the moderators proposed the main conclusions of each workshop and opened a round of discussion where all attendees participated. Results: This document and its conclusions emanate from the presentations made by the speakers and the discussions and agreements of each workshop. Both have been approved after several corrections by all authors before being submitted for publication. They have also obtained the official scientific recognition of the Spanish Society of Oral and Maxillofacial Surgery and should serve as a basis for future scientific studies and meetings. Conclusions: The main objective when we perform a sinus bone graft is vital bone formation in the maxillary sinus, to achieve long-term survival of the implants after prosthetic loading. To do this, the technique and sequence of treatment should aim to achieve predictable and stable results over time, although this involves a longer waiting time. The initial implant stability is the key factor for osseointegration and should be the main criterion to indicate simultaneous or delayed implants in the maxillary sinus.

5.972 JCR (2008) Q1, 5/79 Cardiac & cardiovascular systems

Oligo-D-glucosamine (‘‘oligomer’’ of chitosan) seems well suited for injectable, biodegradable systems (IBS), due to their solubility in water, easier funtionalization and the possibility of working at high concentrations. Chitosan was enzymatically degraded with a commercial enzyme (Multifect Pectinase FE) at 508C and pH 5.5 during 17h, adapting a previous procedure. The oligomers were precipitated in ethanol and analysed by MALDI-TOF/MS and FTIR. They were then functionalized by reaction with methacrylic anhydride (MethA), varying ratio of amount of substance of MethA : amount of substance of -NH2 groups in the oligomer. The obtained methacrylamide- oligomers were polymerized with a potassium persulfate/ vitamin C initiation system. Both the modified oligomers and the polymerized product were analysed by FTIR and NMR. [...], info:eu-repo/semantics/publishedVersion

En: Electrophoresis. 2004, 25 (13) : 2056-2064 p.. 1522-2683

Acrylic bone cements prepared with activators of reduced toxicity have been formulated with the aim of improving the biocompatibility of the final material. The activators used were N,N-dimethylaminobenzyl alcohol (DMOH) and 4,4 -dimethylamino benzydrol (BZN). The toxicity, cytotoxicity, and antiseptic action of these activators were first studied. DMOH and BZN presented LD50 values 3–4 times higher than DMT, were less cytotoxic against polymorphonuclear leucocytes, and possessed an antimicrobial character, with a high activity against the most representative microorganisms involved in postoperative infections. The properties of the acrylic bone cements formulated with DMOH and BZN were evaluated to determine the influence of these activators on the curing process and the physicochemical characteristics of the cements. A decrease of the peak temperature was observed for the curing with DMOH or BZN with respect to that of one commercially available formulation (CMW 3). However, residual monomer content and mechanical properties in tension and compression were comparable to those of CMW 3. The biocompatibility of acrylic bone cements containing DMOH or BZN was studied and compared with CMW 3. To that end, intramuscular and intraosseous implantation procedures were carried out and the results were obtained from the histological analysis of the surrounding tissues at different periods of time. Implantation of rods of cement into the dorsal muscle of rats showed the presence of a membrane of connective tissue, which increased in collagen fibers with time of implantation, for all formulations. The intraosseous implantation of the cements in the dough state in the femur of rabbits, revealed a higher and early osseous neoformation, with the presence of osteoid material surrounding the rest of the cured material, for the cement prepared with the activator BZN in comparison with that obtained following the implantation of the cement cured with DMOH or DMT (CMW 3)

An experimental study of platelet aggregation was performed in 22 male Landrace x Large-White crossbred pigs treated with propofol at different doses, to compare the results of optical aggregometry with those of the PFA-100 (Dade Int., Miami, FL, USA), a new platelet function analyzer. Platelet aggregation was analyzed in basal blood samples by both methods, after which the pigs were divided into three groups: G1, anaesthetic induction with propofol (2 mg/kg intravenously (i.v.)); G2, anaesthetic induction with propofol (2 mg/kg i.v.), followed by a second dose of 1.5 mg/kg; and G3, anaesthetic induction with propofol (2 mg/kg i.v.), followed by 1 h of continuous i.v. infusion at 13 mg/kg/h. Four minutes after propofol injection, blood samples were again taken from each group and studied by both methods. In groups G2 and G3, both methods showed reduced platelet aggregation, while in group G1 neither evidenced an anti-aggregating effect of propofol. Under our experimental conditions: (1) the propofol effect on platelet aggregation depends on the plasma concentration; (2) the results obtained with the two methods are comparable; (3) PFA-100 may provide an alternative to optical aggregometry for detecting the effects of anaesthetic agents ex vivo.

Hydrogels based on polymeric derivatives of vitamin E for biomedical purposes have been prepared by copolymerization reaction of the alpha-tocopheryl methacrylate (V) with 2-hydroxyethyl methacrylate (H) in a range of composition between 5-20 wt % of V. The swelling behavior of the hydrogels in water, alkaline, and acidic media showed a slight decrease in the equilibrium water content with the content of V in the copolymer although in all cases it was superior to an EWC > 20%. The diffusion mechanism followed a Fickian behavior in all media. The values of the diffusion coefficients were in the range 2.5-1.6 10(-7) cm2/s. The states of water in the hydrogels were determined by DSC. A decrease in the content of freezing water was obtained with the V content for all media, and for all compositions lower values of freezing water were obtained in acidic or basic pHs than in distilled water. The copolymeric xerogels, analyzed by contact angle measurements, deviated from those expected taking into consideration those of the homopolymers and the average fraction of the monomers in the copolymer. The polar contribution dropped with the introduction of a small content (4 wt %) of the vitamin E-containing monomer, and it reached a value similar to that of poly-V for a composition of 49 wt % of V in the copolymer. This behavior is accounted for by the segregation of the macromolecular chains of both kinds of monomers, due mainly to differences in their polarity, molecular weights, and the reactivity of both monomers. Finally, thermogravimetric analysis showed a higher thermal (antioxidant) stability of the poly-V with respect to poly-H, giving rise to a residue of 18 wt %. The V-containing copolymers also showed an improved stability (antioxidant behavior), indicating the possibility of the V unit's interfering with the oxidative process, based on free-radical species, and, therefore, with the aging process at the cellular level.

A hydrogel containing vitamin E (a-tocopherol) was prepared by free radical polymerization of 2-hydroxyethyl methacrylate (HEMA) and a-tocopheryl methacrylate (VEMA), the latter being synthesized previously to its use. The hydrogel containing 20 wt% of VEMA showed equilibrium water content in the range of those of hydrogel networks, at any pH. The swelling of the hydrogel followed Fick's law, indicating that sorption of water molecules is controlled by diffusion, although the values of diffusion coef®cients for the VEMA-containing hydrogel were lower than those of poly-HEMA in any medium. Surface characterization of the VEMAcontaining hydrogel revealed a decrease in the surface energy of solid owing to a decrease of the polar component mainly. The application of ®nely powdered xerogel of HEMA±VEMA copolymer bearing 20 wt% of the vitamin E derivative gave a very fast and positive response showing an activated regeneration capacity, probably due to the stimulation of the cellular proliferation or the more plausible effect, the cellular protection associated to the antioxidant properties of the vitamin E residue., Financial support from CICYT, Mat 96-0981, and CAM, 08.4/0007/1997, are gratefully acknowledged.

Acrylic bone cements become radio-opaque by the addition of an inorganic compound, commonly BaSO4 or ZrO2. However, the use of these additives has some negative effects such as loss of mechanical properties, risk of release and bone resorption. The use of the monomer 2,5-diiodo-8-quinolyl methacrylate (IHQM), which shows adequate polymerization and radio-opacity properties, is proposed as a new X-ray opaque, methacrylate iodine-containing agent. The aim of this study is to determine the effect of this new radio-opaque agent on the mechanical properties of acrylic bone cements. The addition of the iodine-containing methacrylate provides a statistically significant increase in the tensile strength, fracture toughness and ductility, with respect to the barium sulphate-containing cement. This effect can be attributed to the fact that the use of a radio-opaque monomer eliminates the porosity associated with the barium sulfate particles, which show no adhesion to the matrix. However, some reinforcing effect must also be attributed to the iodine-containing monomer, since the tensile and fracture toughness values reached are even higher than those shown by the radiolucent cement.

This work describes the influence of surface pretreatments over the nucleation and growth of an apatite layer, formed by a biomimetic process, on which a bioactive glass is used as a precursor of the calcium-phosphate (Ca-P) formation on the materials surface. SEVA-C, a corn starch-based biodegradable blend, was used as substrate. The surfaces were pretreated during various periods by: (i) physical methods, namely ultraviolet radiation (u.v.), and over exposure to ethylene oxide sterilization (EtO); and (ii) chemical methods, namely potassium hydroxide (KOH) and acetic anhydride (CH3CO)2 etchings. The surface modifications, performed before the production of the biomimetic coatings, resulted in a faster formation of Ca-P nuclei during the first stages of SBF immersion, particularly in the case of the KOH etching. In this case, it was possible to observe a decrease in the average surface roughness, as measured by laser profilometry, and an increase of the hydrophilicity of the material, which was evident from a clear increment in the water-uptake ability and quantified by contact angle measurements. With this treatment it was possible not only to reduce the induction period for the formation of a well defined and dense apatite-like layer, as observed by scanning electron microscopy (SEM), but also to improve the adhesion of the Ca-P layer to the substrate, as confirmed by the adhesion strength tests. For all the studied pre-treatments, the composition of the films, analyzed by energy dispersive spectroscopy (EDS) and identified by thin-film X-ray diffraction (TF-XRD), seems to be very similar to that of human bone apatites., EU Leonardo da Vinci grant

Groundwater discharge from the Iberian Chain into the Ebro tertiary basin takes place through the mesozoic carbonated rocks. These rocks extend from La Rioja to the Mediterranean sea. In this work, it is shown the Jurassic aquifer equipotential levels map as well as the groundwater flow directions. The recharge and discharge areas, the aquifer-river relationship, and the hydrogeological limits of the aquifer are also shown

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This paper describes a polymer site-specific delivery system containing human growth hormone in an in vivo model of scarring in the diabetic state. Copolymer discs with the hormone were introduced into incisions made in rats previously injected with streptozotocin in order to induce diabetes. Tissue specimens for evaluation were obtained at 3, 7 or 10 days after the procedure. Study groups were healthy rats and diabetic rats untreated or treated with/without the hormone. Histological sections were prepared for light microscopy examination of wound zones. Three and 7 days after surgery, polymer remains could be observed in the subcutaneous tissue. These remnants induced a moderate foreign body reaction. The number of macrophages detected was directly related to neovessel formation and metalloelastase expression. The CD4+/CD8+ ratio was low during the initial follow up stages (3 and 7 days) in untreated diabetic rats, yet an increased ratio corresponding to areas around the polymer remains was noted in the animals treated with copolymer loaded with the growth hormone. Copolymer is biodegradable in vivo and may be used as a vehicle for the slow release of active substances. The presence of the hormone at the site of skin injury induces cell proliferation and enhances the repair process.

Graft copolymers of poly(ϵ‐caprolactone) (PCL) on poly(dimethylacrylamide) (PDMAm), poly(methylmethacrylate) (PMMA), or on copolymers of poly(DMAm‐co‐MMA) have been synthesized and characterized by 1H NMR spectroscopy, differential scanning calorimetry (DSC), and size exclusion chromatography (SEC). These partially biodegradable copolymer matrices have been proposed as drug delivery systems for the release of low‐molecular‐weight glycosides. Octyl‐N‐acetyl‐6‐O‐[2,2‐bis(hydroxymethyl)‐3‐hydroxypropyl]‐α‐D‐glucosamide, a synthetic carbohydrate able to inhibit the proliferation of human malignant glioma cells in culture and transplanted glioma in rats was selected as drug model. The in vitro aqueous behavior of four drug‐loaded and unloaded graft copolymers of different MMA: DMAm and PCL ratios has been analyzed performing swelling, degradation, and drug release experiments. An intimate dependence of the aqueous behavior with the composition has been found. The higher was the DMAm content, the higher was the hydrophilicity of the synthesized systems as well as the swelling, degradation, and drug release rate. In vivo experiments in pigs demonstrated the very good tolerance of drug‐loaded implanted polymeric discs, and that >95% of the charged drug is released after 2 months' implantation. Fil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Consejo Superior de Investigaciones Científicas; España. Instituto en Ciencia y Tecnología de Polímeros; España Fil: Gallardo, Alberto. Consejo Superior de Investigaciones Científicas; España. Instituto en Ciencia y Tecnología de Polímeros; España Fil: San Roman, Julio. Consejo Superior de Investigaciones Científicas; España. Instituto en Ciencia y Tecnología de Polímeros; España Fil: Fernández Mayoralas, Alfonso. Consejo Superior de Investigaciones Científicas; España. Instituto de Química Orgánica General; España Fil: Zurita, Mercedes. Clínica Puerta de Hierro; España Fil: Vaquero, Jesús. Clínica Puerta de Hierro; España

Fundamento. El objetivo de este artículo es determinar la prevalencia y conocer los cambios epidemiológicos más relevantes en la última década en la infección del tracto urinario (ITU) en los servicios de urgencias (SU), así como el perfil y manejo de los pacientes. Métodos. Estudio descriptivo con análisis transversal, multicéntrico en 49 SU españoles durante 12 meses. Se incluyeron todos los pacientes con el diagnóstico de ITU y de infección. Se registraron todos los pacientes atendidos en los SU. Resultados. Se incluyeron 2.517 casos diagnosticados de ITU con una edad media de 55 ± 23 años, el 64,6% mujeres. Estos representan el 22% de las infecciones y el 3,2% de todos los pacientes del SU. El 36% de las ITU se registraron en pacientes con 70 o más años. El 51,9% tenían alguna enfermedad de base (16,5% diabetes mellitus) y el 32,7% alguno de los factores de riesgo de multirresistencia para bacterias. El 8,3% cumplían criterios de sepsis. El 71,9% de los pacientes recibieron el alta desde el SU. Conclusiones. Las ITU son infecciones muy frecuentes en los SU, con importante comorbilidad asociada, elevada edad media y predominio en mujeres. Respecto a una década anterior, las ITU han aumentado su prevalencia (3,2% frente a 2,1%) y el paciente tiene más edad [55,5 (DE 23) frente a 52 (DE 22) años], mayor comorbilidad (51,9% frente a 40,6%) y gravedad clínica (8,3% frente a 6,5%).

In the present study, semi- and interpenetrated polymer network (IPN) systems based on hyaluronic acid (HA) and chitosan using ionic crosslinking of chitosan with a bioactive crosslinker, glycerylphytate (G1Phy), and UV irradiation of methacrylate were developed, characterized and evaluated as potential supports for tissue engineering. Semi- and IPN systems showed significant di erences between them regarding composition, morphology, and mechanical properties after physicochemical characterization. Dual crosslinking process of IPN systems enhanced HA retention and mechanical properties, providing also flatter and denser surfaces in comparison to semi-IPN membranes. The biological performance was evaluated on primary human mesenchymal stem cells (hMSCs) and the systems revealed no cytotoxic e ect. The excellent biocompatibility of the systems was demonstrated by large spreading areas of hMSCs on hydrogel membrane surfaces. Cell proliferation increased over time for all the systems, being significantly enhanced in the semi-IPN, which suggested that these polymeric membranes could be proposed as an e ective promoter system of tissue repair. In this sense, the developed crosslinked biomimetic and biodegradable membranes can provide a stable and amenable environment for hMSCs support and growth with potential applications in the biomedical field., La Caixa Foundation 100010434 LCF/BQ/ES16/11570018, Spanish Ministry of Economy and Competitiveness RTC-2016-5451-1, Instituto de Salud Carlos III FMM-AP17196-2019

Novel fully bio-based poly(lactic acid) copoly(ester-urethane)s have been successfully synthesized. The new system is composed of a series of A-B-A triblock copolymers, where A, hard block, is poly(lactic acid) and B, soft block, is an ad hoc designed random aliphatic copolyester, poly(butylene succinate/azelate), characterized by high flexibility. Triblock units are joined by hexamethylene diisocyanate, known chain extender that allows the obtaining of polymers with high molecular weights. The samples synthesized were subjected to a detailed molecular, thermal, structural and mechanical characterization. The results obtained, show that copolymerization leads to better mechanical response with respect to poly(lactic) acid homopolymer. Moreover, the presence of the soft block in the main polymer chain facilitates the process of biodegradability. Nanoparticles of selected copolymers fabricated by using the nanoprecipitation method showed rounded morphology and average hydrodynamic diameters around 180 nm. Cellular behavior was assessed using human fibroblasts in vitro assays and results showed absence of cytotoxicity and a good cellular adhesion and proliferation on all the copolymer surfaces.