Morphology, Crystallinity, and Molecular Weight of Poly(E-caprolactone)/Graphene Oxide Hybrids

[EN] A study was carried out to determine the effects of graphene oxide (GO) filler on the properties of poly(epsilon-caprolactone) (PCL) films. A series of nanocomposites were prepared, incorporating different graphene oxide filler contents (0.1, 0.2, and 0.5 wt%) by the solution mixing method, and an in-depth study was made of the morphological changes, crystallization, infrared absorbance, molecular weight, thermal properties, and biocompatibility as a function of GO content to determine their suitability for use in biomedical applications. The infrared absorbance showed the existence of intermolecular hydrogen bonds between the PCL's carbonyl groups and the GO's hydrogen-donating groups, which is in line with the apparent reduction in molecular weight at higher GO contents, indicated by the results of the gel permeation chromatography (GPC), and the thermal property analysis. Polarized optical microscopy (POM) showed that GO acts as a nucleating point for PCL crystals, increasing crystallinity and crystallization temperature. The biological properties of the composites studied indicate that adding only 0.1 wt% of GO can improve cellular viability and that the composite shows promise for use in biomedical applications.This work was supported by Projects GV/2016/067 of the Generalitat Valenciana and MAT2016-76039-C4-3-R of the Spanish Ministry of Economy and Competitiveness (MINECO). The authors are grateful to M. Monleon-Pradas for his helpful comments and G. Vilarino-Feltrer for his valuable advice on the cell culture experiments. A. Vidaurre would also like to express her gratitude for the support received from CIBER-BBN, an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. SEM, TEM and AFM were conducted by the authors at the Microscopy Service of the Universitat Politecnica de Valencia, whose advice is greatly appreciated.Castilla Cortázar, MIC.; Vidaurre, A.; Marí, B.; Campillo Fernandez, AJ. (2019). Morphology, Crystallinity, and Molecular Weight of Poly(E-caprolactone)/Graphene Oxide Hybrids. Polymers. 11(7):1-19. https://doi.org/10.3390/polym11071099S119117Hummers, W. S., & Offeman, R. E. (1958). Preparation of Graphitic Oxide. Journal of the American Chemical Society, 80(6), 1339-1339. doi:10.1021/ja01539a017Stankovich, S., Piner, R. D., Nguyen, S. T., & Ruoff, R. S. (2006). Synthesis and exfoliation of isocyanate-treated graphene oxide nanoplatelets. Carbon, 44(15), 3342-3347. doi:10.1016/j.carbon.2006.06.004Dreyer, D. R., Park, S., Bielawski, C. W., & Ruoff, R. S. (2010). The chemistry of graphene oxide. Chem. Soc. Rev., 39(1), 228-240. doi:10.1039/b917103gKonios, D., Stylianakis, M. M., Stratakis, E., & Kymakis, E. (2014). 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Analysis of the 'Endoworm' prototype's ability to grip the bowel in in vitro and ex vivo models

[EN] Access to the small bowel by means of an enteroscope is difficult, even using current devices such as single-balloon or double-balloon enteroscopes. Exploration time and patient discomfort are the main drawbacks. The prototype 'Endoworm' analysed in this paper is based on a pneumatic translation system that, gripping the bowel, enables the endoscope to move forward while the bowel slides back over its most proximal part. The grip capacity is related to the pressure inside the balloon, which depends on the insufflate volume of air. Different materials were used as in vitro and ex vivo models: rigid polymethyl methacrylate, flexible silicone, polyester urethane and ex vivo pig small bowel. On measuring the pressure-volume relationship, we found that it depended on the elastic properties of the lumen and that the frictional force depended on the air pressure inside the balloons and the lumen's elastic properties. In the presence of a lubricant, the grip on the simulated intestinal lumens was drastically reduced, as was the influence of the lumen's properties. This paper focuses on the Endoworm's ability to grip the bowel, which is crucial to achieving effective endoscope forward advance and bowel foldingThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The study was funded by the Spanish Ministry of Economy and Competitiveness through Project (PI18/01365) and by the UPV/IIS LA Fe through the (Endoworm 3.0) Project. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with the assistance of the European Regional Development FundTobella, J.; Pons-Beltrán, V.; Santonja, A.; Sánchez-Diaz, C.; Campillo Fernandez, AJ.; Vidaurre, A. (2020). 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Materials Science Toolkit for Carbon Footprint Assessment: A Case Study for Endoscopic Accessories of Common Use

[EN] Ironically, healthcare systems are key agents in respiratory-related diseases and estimated deaths because of the high impact of their greenhouse gas emissions, along with industry, transportation, and housing. Based on safety requirements, hospitals and related services use an extensive number of consumables, most of which end up incinerated at the end of their life cycle. A thorough assessment of the carbon footprint of such devices typically requires knowing precise information about the manufacturing process, rarely available in detail because of the many materials, pieces and steps involved during the fabrication. And yet, tools most often used for determining the environmental impact of consumer goods just require a bunch of parameters, mainly based on the material composition of the device. Here we report a basic set of analytical methods that provide the information required by the software OpenLCA to calculate the main outcome related to environmental impact, the greenhouse gas emissions. Through thermogravimetry, calorimetry, infrared spectroscopy and elemental analysis we proved that obtaining relevant data for the calculator in the exemplifying case of endoscopy tooling or accessories is possible. This routine procedure opens the door to a broader, more accurate analysis of the environmental impact of everyday work at hospital services, offering potential alternatives to minimize it.This study has been funded by Instituto de Salud Carlos III (ISCIII) through the project PI21/00193 and cofunded by the European Union. Funding: Instituto de Salud Carlos III (ISCIII), PI21/00193, cofunded by the European Union. And through the project PI2023-6 from UPV-LaFe innovation projects.Martín-Cabezuelo, R.; Vilariño-Feltrer, G.; Campillo Fernandez, AJ.; Lorenzo-Zúñiga, V.; Pons, V.; López-Muñoz, P.; Tort-Ausina, I. (2023). Materials Science Toolkit for Carbon Footprint Assessment: A Case Study for Endoscopic Accessories of Common Use. ACS Environmental Au. https://doi.org/10.1021/acsenvironau.3c0004

Functionalization of 3D scaffolds with protein-releasing biomaterials for intracellular delivery

[EN] Appropriate combinations of mechanical and biological stimuli are required to promote proper colonization of substrate materials in regenerative medicine. In this context, 3D scaffolds formed by compatible and biodegradable materials are under continuous development in an attempt to mimic the extracellular environment of mammalian cells. We have here explored how novel 3D porous scaffolds constructed by polylactic acid, polycaprolactone or chitosan can be decorated with bacterial inclusion bodies, submicron protein particles formed by releasable functional proteins. A simple dipping-based decoration method tested here specifically favors the penetration of the functional particles deeper than 300 μm from the materials' surface. The functionalized surfaces support the intracellular delivery of biologically active proteins to up to more than 80% of the colonizing cells, a process that is slightly influenced by the chemical nature of the scaffold. The combination of 3D soft scaffolds and protein-based sustained release systems (Bioscaffolds) offers promise in the fabrication of bio-inspired hybrid matrices for multifactorial control of cell proliferation in tissue engineering under complex architectonic setting-ups.We are indebted to MINECO (BFU2010-17450), AGAUR (2009SGR-0108 and SGR2009-516), DGI (CTQ2010-19501) and CIBER de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN, Spain) for funding our research on Inclusion bodies. CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, and Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. EGF is supported by the Programa Personal de Tecnico de Apoyo (Modalidad Infraestructuras cientifico-tecnologicas, MICINN). We also thank technical assistance from the Servei de Cultius Celulars, Produccio d'Anticossos i Citometria (SCAC) Laboratori de Luminescencia i Espectroscopia de Biomolecules (LLEB) and Servei de Microscopia, all at the Universitat Autonoma de Barcelona (UAB). We are also indebted to the Protein Production Platform (CIBER-BBN) for helpful technical assistance and for protein production and purification services (http://bbn.ciber-bbn.es/programas/plataformas/equipamiento). AV received an ICREA ACADEMIA award.Seras-Franzoso, J.; Steurer, C.; Roldan, M.; Vendrell, M.; Vidaurre-Agut, C.; Tarruella, A.; Saldana, L.... (2013). Functionalization of 3D scaffolds with protein-releasing biomaterials for intracellular delivery. Journal of Controlled Release. 171(1):63-72. https://doi.org/10.1016/j.jconrel.2013.06.034S6372171

Production and enzymatic degradation of poly (epsilon-caprolactone)/graphene oxide composites

[EN] Poly(epsilon-caprolactone) (PCL) based composites containing different graphene oxide (GO) contents (0.1, 0.2 and 0.5 wt%) were produced by the solution mixing method followed by compression molding and enzymatically degraded in a pH 7.4 phosphate buffer solution containing Pseudomonas lipase at 37 degrees C. Morphological changes, molecular weight, calorimetric and mechanical properties were analyzed according to graphene oxide content. The study of tensile properties showed that the composites increased their Young's modulus, while tensile strength and elongation at break decreased to significantly less than that of neat PCL. PCL composite crystallinity was evaluated by differential scanning calorimetry (DSC). It was found that incorporating GO can reduce nucleation activity as well as crystallization rates, from 67.6% for neat PCL to 50.6% for a composite with 0.5 wt% GO content. For enzymatic degradation, the weight loss data showed that incorporating GO into the PCL significantly altered enzymatic degradation. The presence of GO did not alter PCL's hydrolysis mechanism, but did slow down composite enzymatic degradation in proportion to the percentage of filler content.I. Castilla-Cortazar and A. J. Campillo-Fernandez are grateful for the support of the Spanish Ministry of Science, Innovation and Universities, through RTE2018-095872-13-C22/ERDF. A. Vidaurre would like to express her gratitude for the support of the Spanish Ministry of Science and Education, through the MAT2016-76039-C4-1-R Project, and also the support from CIBER-BBN, an initiative funded by the Sixth National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions financed by the Institute de Salud Carlos III with assistance from the European Regional Development Fund. The FESEM, TEM and mechanical tests were conducted by the authors at the Microscopy Service of the Universitat Politecnica de Valencia, whose advice is greatly appreciated,Martínez-Ramón, V.; Castilla Cortázar, MIC.; Vidaurre, A.; Campillo Fernandez, AJ. (2020). Production and enzymatic degradation of poly (epsilon-caprolactone)/graphene oxide composites. Materials Express. 10(6):866-876. https://doi.org/10.1166/mex.2020.1702S86687610

Poly(epsilon-caprolactone)/Graphene oxide composite systems: a comparative study on hydrolytic degradation at extreme pH values

[EN] Polycaprolactone/Graphene oxide (PCL/GO) composites are shown to be promising substrates for tissue engineering as their degradation behavior is a key aspect in this type of application. The present paper studies the effect of different GO contents (0.1, 0.2 and 0.5 wt%) of PCL/GO composites on accelerated hydrolytic degradation at pH 13 and pH 1. Degradation kinetics at pH 13 is strongly affected by GO content, and speed up at higher percentages. The composite with 0.5 wt% of GO was completely degraded in 72 hours, while degradation at pH 1 presents a different profile and seems to have an induction period that lasts more than 1500 hours. Morphological changes, molecular weight distribution, weight loss, degree of swelling and calorimetric properties were obtained as a function of degradation time. According to the results obtained, the addition of small percentages of GO significantly influences the degradation behavior of the composites acting as degradation modulators.Isabel Castilla-Cortazar and Alberto J. Campillo-Fernandez are grateful for the support of the Spanish Ministry of Science, Innovation and Universities, through RTI2018-095872-B-C22/ERDE Ana Vidaurre would like to express her gratitude for the support of the Spanish Ministry of Science and Education, through the MAT2016-76039-C4-1-R Project, and also the support from CIBER-BBN, an initiative funded by the Sixth National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CII3ER Actions financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Campillo Fernandez, AJ.; González-Reed, P.; Vidaurre, A.; Castilla Cortázar, MIC. (2020). Poly(epsilon-caprolactone)/Graphene oxide composite systems: a comparative study on hydrolytic degradation at extreme pH values. Materials Express. 10(6):892-902. https://doi.org/10.1166/mex.2020.1728S89290210

Colombian surgical outcomes study insights on perioperative mortality rate, a main indicator of the lancet commission on global surgery – a prospective cohort studyResearch in context

Summary: Background: Surgical care holds significant importance in healthcare, especially in low and middle-income countries, as at least 50% of the 4.2 million deaths within the initial 30 days following surgery take place in these countries. The Lancet Commission on Global Surgery proposed six indicators to enhance surgical care. In Colombia, studies have been made using secondary data. However, strategies to reduce perioperative mortality have not been implemented. This study aims to describe the fourth indicator, perioperative mortality rate (POMR), with primary data in Colombia. Methods: A multicentre prospective cohort study was conducted across 54 centres (hospitals) in Colombia. Each centre selected a 7-day recruitment period between 05/2022 and 01/2023. Inclusion criteria involved patients over 18 years of age undergoing surgical procedures in operating rooms. Data quality was ensured through a verification guideline and statistical analysis using mixed-effects multilevel modelling with a case mix analysis of mortality by procedure-related, patient-related, and hospital-related conditions. Findings: 3807 patients were included with a median age of 48 (IQR 32–64), 80.3% were classified as ASA I or II, and 27% of the procedures had a low-surgical complexity. Leading procedures were Orthopedics (19.2%) and Gynaecology/Obstetrics (17.7%). According to the Clavien–Dindo scale, postoperative complications were distributed in major complications (11.7%, 10.68–12.76) and any complication (31.6%, 30.09–33.07). POMR stood at 1.9% (1.48–2.37), with elective and emergency surgery mortalities at 0.7% (0.40–1.23) and 3% (2.3–3.89) respectively. Interpretation: The POMR was higher than the ratio reported in previous national studies, even when patients had a low–risk profile and low-complexity procedures. The present research represents significant public health progress with valuable insights for national decision-makers to improve the quality of surgical care. Funding: This work was supported by Universidad del Rosario and Fundación Cardioinfantil-Instituto de Cardiología grant number CTO-057-2021, project-ID IV-FGV017

Human immunodeficiency virus continuum of care in 11 european union countries at the end of 2016 overall and by key population: Have we made progress?

Background. High uptake of antiretroviral treatment (ART) is essential to reduce human immunodeficiency virus (HIV) transmission and related mortality; however, gaps in care exist. We aimed to construct the continuum of HIV care (CoC) in 2016 in 11 European Union (EU) countries, overall and by key population and sex. To estimate progress toward the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 target, we compared 2016 to 2013 estimates for the same countries, representing 73% of the population in the region. Methods. A CoC with the following 4 stages was constructed: number of people living with HIV (PLHIV); proportion of PLHIV diagnosed; proportion of those diagnosed who ever initiated ART; and proportion of those ever treated who achieved viral suppression at their last visit. Results. We estimated that 87% of PLHIV were diagnosed; 92% of those diagnosed had ever initiated ART; and 91% of those ever on ART, or 73% of all PLHIV, were virally suppressed. Corresponding figures for men having sex with men were: 86%, 93%, 93%, 74%; for people who inject drugs: 94%, 88%, 85%, 70%; and for heterosexuals: 86%, 92%, 91%, 72%. The proportion suppressed of all PLHIV ranged from 59% to 86% across countries. Conclusions. The EU is close to the 90-90-90 target and achieved the UNAIDS target of 73% of all PLHIV virally suppressed, significant progress since 2013 when 60% of all PLHIV were virally suppressed. Strengthening of testing programs and treatment support, along with prevention interventions, are needed to achieve HIV epidemic control