Perfusion Decellularization of Extrahepatic Bile Duct Allows Tissue-Engineered Scaffold Generation by Preserving Matrix Architecture and Cytocompatibility

Reconstruction of bile ducts damaged remains a vexing medical problem. Surgeons have few options when it comes to a long segment reconstruction of the bile duct. Biological scaffolds of decellularized biliary origin may offer an approach to support the replace of bile ducts. Our objective was to obtain an extracellular matrix scaffold derived from porcine extrahepatic bile ducts (dECM-BD) and to analyze its biological and biochemical properties. The efficiency of the tailored perfusion decellularization process was assessed through histology stainings. Results from 4’-6-diamidino-2-phenylindole (DAPI), Hematoxylin and Eosin (H&E) stainings, and deoxyribonucleic acid (DNA) quantification showed proper extracellular matrix (ECM) decellularization with an effectiveness of 98%. Immunohistochemistry results indicate an effective decrease in immunogenic marker as human leukocyte antigens (HLA-A) and Cytokeratin 7 (CK7) proteins. The ECM of the bile duct was preserved according to Masson and Herovici stainings. Data derived from scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) showed the preservation of the dECM-BD hierarchical structures. Cytotoxicity of dECM-BD was null, with cells able to infiltrate the scaffold. In this work, we standardized a decellularization method that allows one to obtain a natural bile duct scaffold with hierarchical ultrastructure preservation and adequate cytocompatibility

Online clinical simulation session with human avatars: Teaching innovation in medical students

La pandemia COVID-19, ha obligado a las instituciones académicas a implantar diferentes metodologías hibridas (presencial y a distancia), la educación basada en simulación no es la excepción, esta se ha adaptado a la formación a distancia (telesimulación). Se presenta un procedimiento de simulación en línea, con avatares humanos presentes en el escenario de simulación, que se identifican con cada uno de los estudiantes en remoto, desarrollan la acción que estos indican en tiempo real, recibiendo los alumnos retroalimentación inmediata; lo que favorece el aprendizaje significativo. Se analizan las ventajas de distintas modalidades de telesimulación, se propugna que la simulación con avatares humanos facilita el aprendizaje cognitivo, afectivo y psicomotor en los estudiantes, favorece el trabajo en equipo, la interacción social; y es capaz de crear una comunidad de investigación con presencia cognitiva, social y docente. La simulación clínica con avatares humanos constituye un nuevo procedimiento en simulación en línea, que podría contribuir a mejorar la formación médica. Se propone continuar con la evidencia empírica y la investigación científica sobre este nuevo modelo de telesimulación.The COVID-19 pandemic has forced academic institutions to implement different hybrid methodologies (face-to-face and distance), simulation-based education is no exception, it has been adapted to distance training, such as telesimulation. An online simulation procedure is presented, with human avatars present in the simulation scenario, who identify with each of the students remotely, develop the action that they indicate in real time, receiving immediate feedback from the students; which promotes meaningful learning. The advantages of different telesimulation modalities are analyzed, it is advocated that simulation with human avatars facilitates cognitive, affective and psychomotor learning in students, favors teamwork, social interaction; and is capable of creating a research community with a cognitive, social and teaching presence. Clinical simulation with human avatars constitutes a new procedure in online simulation, which could contribute to improving medical training. It is proposed to continue with the empirical evidence and scientific research on this new telesimulation model

Revista de Vertebrados de la Estación Biológica de Doñana

Tiempo y orden de aparición de las escamas en el salmón del Atlántico (Salmo salar)Estudios sobre el sapo corredor (Bufo calamita) en el sur de España.III. ReproducciónInfluencia de las carecterísticas del medio acuático sobre las poblaciones de larvas de anfibios en lala Reserva Biológica de Doñana(Huelva, EspañaDieta de la cigüeñuela (Himantopus himantopus) en las salinas del estuario del GuadianaOrientación y selección del lugar del nido en el gorrión moruno (Passer hispaniolensis)la avifauna de las Vegas Bajas del Guadianala reproducción de la malvasía (Oxyura leucocephala) en el sur de la provincia de Córdoba, España.La alimentación de la curruca cabecinegra (Sylvia melanocephala, Gmelin 1788) en olivares de la provincia de Jaén (otoño-invierno)Consideraciones sobre el efecto de los conejos y los grandes herbívoros en los pastizales de la Vera de DoñanaAnálisis factorial de las expresiones faciales del babuino sagrado (Papio hamadryas)Contaminación xenobiótica del Parque Nacionalde Doñana. II. Residuos de insecticidas organoclorados, bifenilos policlorados, (PGBs) y metales pesados en Falconiformes y StrigiformesTransferencia total y del y bioacumulación de mercurio y metilmercurio en ecosistemas del Parque Nacional de DoñanaNota sobre la alimentación de larvas de anfibios: I. Pleurodeles waltl en charcas temporaleNota sobre nuevas especies parasitada por el críalo (Clamator glandarius) en EspañaEstructura de la jerarquización en la predación de huevos y pichones en Spheniscus magellanicusPasser domesticus, nueva specie para Bolivia¿Están realmente subalimentados los cernícalos primilla en el valle del Guadalquivir durante el periodo no reproductor?.Nidificación del paiño común (Hydrobates pelagicus) en las Islas Canarias.Nuevos datos sobre la presencia del visón europeo (Mustela lutreola L.) en NavarraLa población de gamos del Parque Nacional de Doñana en 1979Puntualización a la nota "predacción de Falco peregrino y Falco subbuteo sobre quirópteros" de Aymerich y García de Castro aparecida en el vol. 9 de esta revista.Peer reviewe

Orthogonal cameras system for tracking of laparoscopic instruments in training environments

Introducción: El análisis del movimiento es una valiosa herramienta para la evaluación de las habilidades psicomotrices en la laparoscopia. Sin embargo, requiere tecnologías para el seguimiento de la actividad de los instrumentos laparoscópicos durante el entrenamiento. En este artículo presentamos una técnica sin sensores para realizar el seguimiento de los movimientos de los instrumentos laparoscópicos basado en un sistema de cámara ortogonal y procesamiento de imágenes de video. Método: Los movimientos de los instrumentos laparoscópicos son capturados con dos cámaras web colocadas en configuración ortogonal. La posición y la orientación en el espacio de trabajo tridimensional se obtienen utilizando marcadores de color colocados en la punta de los instrumentos. Resultados: Las pruebas de precisión mostraron una resolución de 0.14 mm para el desplazamiento, con 1694 cm3 de espacio de trabajo total y 0.54° en los movimientos angulares. Los errores relativos medios del sistema de seguimiento fueron <1%. Las cámaras ortogonales demostraron alta precisión, linealidad y repetibilidad de la captura de movimiento de los instrumentos laparoscópicos. Conclusiones: El sistema propuesto ofrece una manipulación sin restricciones de los instrumentos laparoscópicos y una alternativa de bajo costo para las tecnologías tradicionales de captura de movimiento. ----------ABSTRACT---------- Introduction: Motion analysis is a valuable tool for assessment of psychomotor skills in laparoscopy. Nonetheless, it requires technologies for tracking the activity of the laparoscopic instruments during training. This paper presents a sensor-free system to track the movements of laparoscopic instruments based on an orthogonal camera system and video image processing. Methods: The movements of the laparoscopic instruments are tracked with two webcams placed in an orthogonal configuration. The position and orientation in the three-dimensional workspace are obtained using color markers placed on the tip of the instruments. Results: Accuracy tests show a resolution of 0.14 mm for displacement, with 1694 cm3 of total workspace, and 0.54° in the angular movements. Mean relative errors of the tracking system were <1%. The orthogonal cameras show high precision, linearity, and repeatability of motion recording of the laparoscopic instruments. Conclusion: The proposed system offers unconstrained manipulation of the instruments and a low-cost alternative for traditional tracking technologies

Importancia de la maestría y el doctorado en cirugía general

ResumenAntecedentesEl doctorado es el mayor grado académico que se puede conseguir en las universidades. El programa educativo de posgrado de medicina en México se divide en 2 grandes rubros: la especialidad médica y los estudios de maestría/doctorado.El objetivo de este estudio fue demostrar la importancia de la maestría o doctorado en la especialidad de cirugía general.Material y métodosBúsqueda bibliográfica en la base de datos PubMed, Medline, entre otros, entre los años 1970 y 2015, con posterior análisis de las revisiones bibliográficas encontradas.DiscusiónLos médicos que realizaron estudios de doctorado se destacan por ser líderes en investigación, docencia y actividades académicas. El entrenamiento dual de la especialidad médica con doctorado es un factor significativo que predice una participación activa en proyectos de investigación en las mejores instituciones educativas.ResultadosDe suma importancia es el estudio de un doctorado en la formación integral de médicos especialistas en cirugía, los cuales demuestran mayor capacitación en docencia, investigación y desarrollo de actividades académicas. Actualmente, aunque es poca la proporción de alumnos que concluyen el programa de doctorado, se espera que desempeñen un papel importante en el futuro del personal médico-científico. Se ha demostrado que la mayoría de los médicos con doctorado tienen amplia variedad de opciones profesionales.ConclusiónLa importancia de los estudios de doctorado en la formación de cirugía general estriba en diversas razones, entre las cuales la principal es formar de manera integral a médicos científicos que puedan desarrollarse en clínica, docencia e investigación.AbstractBackgroundThe Doctor of Philosophy is the highest academic degree that can be obtained in universities. Graduate Education Program in Medicine in Mexico is divided into 2 major categories: Medical Specialty and Master studies/Doctor of Philosophy.The objective of this study was to demonstrate the importance of master's degrees and Doctor of Philosophy in general surgery.Material and methodsA literature search in PubMed and Medline among others, from 1970 to 2015 with subsequent analysis of the literature reviews found.DiscussionThe physicians who conducted doctoral studies stand out as leaders in research, teaching and academic activities. Dual training with a doctorate medical specialty is a significant predictor for active participation in research projects within the best educational institutions.ResultsIt is important to study a PhD in the education of doctors specialising in surgery, who show more training in teaching, research and development of academic activities. Currently, although there is a little proportion of students who do not finish the doctoral program, the ones who do are expected to play an important role in the future of medical scientific staff. It has been shown that most doctors with Doctor of Philosophy have wide range of career options.ConclusionThe importance of doctoral studies in the formation of general surgery is due to various reasons; the main one being comprehensively training physician scientists who can develop in clinical, teaching and research

Sesión de simulación clínica en línea con avatares humanos

introducción La pandemia COVID-19, ha obligado a las instituciones académicas a implantar diferentes metodologías hibridas (presencial y a distancia), la educación basada en simulación no es la excepción, esta se ha adaptado al modelo a distancia, como es la telesimulación. Desarrollo de la experiencia de innovación Se presenta un procedimiento de simulación en línea, con avatares humanos presentes en el escenario de simulación, que se identifican con cada uno de los alumnos en remoto, desarrollan la acción que estos indican en tiempo real, recibiendo los alumnos retroalimentación inmediata; lo que favorece&nbsp; el aprendizaje significativo. Discusión de la innovación docente Se analizan las ventajas de distintas modalidades de telesimulación, se propugna que la simulación con avatares humanos facilita el desarrollo cognitivo, afectivo y psicomotor en los alumnos, favorece el trabajo en equipo, la interacción social; y es capaz de crear una comunidad de investigación con presencia cognitiva, social y docente. Conclusiones La simulación clínica con avatares humanos constituye un nuevo procedimiento en simulación en línea, que podría contribuir a mejorar la formación médica. Se propone continuar con la evidencia empírica y la investigación científica sobre este nuevo modelo de telesimulación. Palabras clave: Telesimulación, sesión clínica, simulación avatar, habilidades

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0-4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2-6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society