48 research outputs found

    A standardised approach to the biomechanical evaluation of tracheal grafts

    Full text link
    [EN] The ideal tracheal substitute must have biomechanical properties comparable to the native trachea, but currently there is no standardised approach to evaluating these properties. Here we propose a novel method for evaluating and comparing the properties of tracheal substitutes, thus systematising both measurement and data curation. This system was tested by comparing native rabbit tracheas to frozen and decellularised specimens and determining the histological characteristics of those specimens. We performed radial compression tests on the anteroposterior tracheal axis and longitudinal axial tensile tests with the specimens anastomosed to the jaw connected to a measuring system. All calculations and results were adjusted according to tracheal size, always using variables relative to the tracheal dimensions, thus permitting comparison of different sized organs. The biomechanical properties of the decellularised specimens were only slightly reduced compared to controls and significant in regard to the maximum stress withstood in the longitudinal axis (-0.246 MPa CI [-0.248, -0.145] MPa) and the energy stored per volume unit (-0.124 mJ & BULL;mm(-3) CI [-0.195, -0.055] mJ & BULL;mm(-3)). The proposed method is suitable for the systematic characterisation of the biomechanical properties of different tracheal substitutes, regardless of the size or nature of the substitute, thus allowing for direct comparisons.This research was funded by the 2018 Spanish Society of Thoracic Surgery grant to National Multicentric Study [Number 180101 to N.J.M.-H.] and [PI16-01315 to M.M.-R.] from the Instituto de Salud Carlos III. CIBERER is funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and the Instituto de Salud Carlos III, with assistance from the European Regional Development Fund.Martínez-Hernández, NJ.; Más Estellés, J.; Milián-Medina, L.; Martínez-Ramos, C.; Cerón-Navarro, J.; Galbis-Caravajal, J.; Roig-Bataller, A.... (2021). A standardised approach to the biomechanical evaluation of tracheal grafts. Biomolecules. 11(10):1-12. https://doi.org/10.3390/biom11101461S112111

    Optimization of a decellularized protocol of porcine tracheas. Long-term effects of cryopreservation. A histological study

    Full text link
    [EN] Objective: The aim of this study was to optimize a decellularization protocol in the trachea of Sus scrofa domestica (pig) as well as to study the effects of long-term cryopreservation on the extracellular matrix of decellularized tracheas. Methods: Porcine tracheas were decellularized using Triton X-100, SDC, and SDS alone or in combination. The effect of these detergents on the extracellular matrix characteristics of decellularized porcine tracheas was evaluated at the histological, biomechanical, and biocompatibility level. Morphometric approaches were used to estimate the effect of detergents on the collagen and elastic fibers content as well as on the removal of chondrocytes from decellularized organs. Moreover, the long-term structural, ultrastructural, and biomechanical effect of cryopreservation of decellularized tracheas were also estimated. Results: Two percent SDS was the most effective detergent tested concerning cell removal and preservation of the histological and biomechanical properties of the tracheal wall. However, long-term cryopreservation had no an appreciable effect on the structure, ultrastructure, and biomechanics of decellularized tracheal rings. Conclusion: The results presented here reinforce the use of SDS as a valuable decellularizing agent for porcine tracheas. Furthermore, a cryogenic preservation protocol is described, which has minimal impact on the histological and biomechanical properties of decellularized porcine tracheas.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by grants MAT2016-76039-C4-2-R (MST) and PID2019-106099RB-C42 (MM) from the Ministry of Economy and Competitiveness of the Spanish Government, by grant PI16-01315 from the ISCIII (Ministerio de Ciencia, Innovacion y Universidades, Spain), and by grant PROMETEO/2020/069 (CC) from the local government of the Comunitat Valenciana (Spain), CIBER-BBN and CIBERER are funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions, and the Instituto de Salud Carlos III, with assistance from the European Regional Development Fund.Milián, L.; Sancho-Tello, M.; Roig-Soriano, J.; Foschini, G.; Martínez-Hernández, NJ.; Más Estellés, J.; Ruiz-Sauri, A.... (2021). Optimization of a decellularized protocol of porcine tracheas. Long-term effects of cryopreservation. A histological study. The International Journal of Artificial Organs. 44(12):998-1012. https://doi.org/10.1177/03913988211008912S9981012441

    Tisanópteros asociados al limón mexicano (Citrus x aurantifolia (Christm) Swingle) en Apatzingán, Michoacán, México

    Get PDF
    Objetive. to determine taxonomically the species of Thysanoptera in Mexican lime (Citrus xaurantifolia (Christm) Swingle), to understand their fluctuation and population density, andto calculate their interaction with rainfall.Design/methodology/approach. a simple random sample was used. The collections andsamples were carried out every 15 days, in 10 trees, and in 10 vegetative shoots. Thevegetative parts were washed with soap solution, to separate the thrips that were placed inentomologic containers with alcohol at 70 %. In total, 375 pieces of micromounting wereprepared. The taxonomic determination was by comparison. To understand the interaction ofThysanoptera with rainfall, the information was analyzed through a square polynomial, withthe RS REG. SAS method. 2 Results. the number of Thysanoptera collected was 4968. The species Scolothripssexmaculatus was dominant, followed by Scirtothrips citri, Frankliniella cephalica, and F.bispinosa. Four predator species of mites and thrips were identified: Scolothripssexmaculatus, Leptothrips mcconelli, Stomatothrips brunneus and Scolothrips palidus. Anadult specimen of the genus Microcephalothrips sp. 1 was found, two individuals of thegenera Liothrips and Microcephalothrips sp. 2, and seven of the genus Karnyothrips, whosespecies were not identified. A peak in the fluctuation and population density was detected,which corresponded to the months of January to April. The effect of rainfall was determinant.Limitations on study/implications. Civil unsafety and decapitalization of the lime productsystem.Findings/conclusions. Five dominating species were present in the three localities:Scolothrips sexmaculatus, Scirtothrips citri, Frankliniella bispinosa, F. cephacila and F.curticornis.Objetivo: determinar taxonómicamente las especies de tisanópteros en limón mexicano (Citrus x aurantifolia (Christm) Swingle), conocer su fluctuación y densidad poblacional, y calcular la interacción con la precipitación pluvial.Diseño/metodología/aproximación: Se utilizó un muestreo aleatorio simple. Las recolectasy muestreos fueron realizados cada 15 d, en diez árboles, y en diez brotes vegetativos. Las partes vegetativas fueron lavadas con una solución jabonosa, para separar a los trips, que fueron depositados en frascos entomológicos con alcohol a 70%. En total, se prepararon 375 micromontajes. La determinación taxonómica fue por comparación. Para conocer la 3 interacción de los tisanópteros con la precipitación pluvial, la información se analizó mediante un polinomio cuadrado, con el método RS REG. SAS.Resultados: Se obtuvieron 4968 tisanópteros. La especie Scolothrips sexmaculatus fuedominante, seguida de Scirtothrips citri, Frankliniella cephalica, y F. bispinosa. Seidentificaron cuatro especies depredadoras de ácaros y trips: Scolothrips sexmaculatus,Leptothrips mcconelli, Stomatothrips brunneus y Scolothrips palidus. Se encontró un ejemplaradulto del género Microcephalothrips sp. 1, dos individuos de los géneros Liothrips yMicrocephalothrips sp. 2 y siete del género Karnyothrips cuyas especies no se identificaron.Se detectó un pico en la fluctuación y densidad poblacional, que correspondió a los meses deenero a abril. El efecto de la precipitación pluvial fue determinante.Limitaciones del estudio/implicaciones: Inseguridad civil, y descapitalización del sistema producto limón.Hallazgos/conclusiones: En las tres localidades, se presentaron cinco especies dominantes: Scolothrips sexmaculatus, Scirtothrips citri, Frankliniella bispinosa, F. cephacilay F. curticornis

    Riesgo quirúrgico tras resección pulmonar anatómica en cirugía torácica. Modelo predictivo a partir de una base de datos nacional multicéntrica

    Get PDF
    Introduction: the aim of this study was to develop a surgical risk prediction model in patients undergoing anatomic lung resections from the registry of the Spanish Video-Assisted Thoracic Surgery Group (GEVATS). Methods: data were collected from 3,533 patients undergoing anatomic lung resection for any diagnosis between December 20, 2016 and March 20, 2018. We defined a combined outcome variable: death or Clavien Dindo grade IV complication at 90 days after surgery. Univariate and multivariate analyses were performed by logistic regression. Internal validation of the model was performed using resampling techniques. Results: the incidence of the outcome variable was 4.29% (95% CI 3.6-4.9). The variables remaining in the final logistic model were: age, sex, previous lung cancer resection, dyspnea (mMRC), right pneumonectomy, and ppo DLCO. The performance parameters of the model adjusted by resampling were: C-statistic 0.712 (95% CI 0.648-0.750), Brier score 0.042 and bootstrap shrinkage 0.854. Conclusions: the risk prediction model obtained from the GEVATS database is a simple, valid, and reliable model that is a useful tool for establishing the risk of a patient undergoing anatomic lung resection

    Manual de simulación clínica en especialidades médicas

    Get PDF
    Manual sobre técnicas y modos de simulación clínica en diversas especialidades médicas.La enseñanza y formación en medicina necesita el uso de la simulación. Existen evidencias de su uso desde hace cientos de años, pero, en los últimos años se ha incrementado y diseminado. La simulación clínica está validada científicamente en múltiples contextos médicos y de otras áreas profesionales de la salud. Y es considerada de gran importancia como proceso de entrenamiento y de mejora de las competencias y adquisición de habilidades médicas en campos que incluye desde la historia clínica, comunicación con el paciente, exploración, diagnóstico terapéutica médica-farmacológica y quirúrgica y seguridad al tratar al paciente. Hoy en día, para muchas técnicas y situaciones clínicas es inaceptable llegar junto a los pacientes sin un dominio adquirido en simulación. La simulación puede ocurrir sin el uso de recursos adicionales, solo las personas, o utilizando pocos o muchos recursos de baja hasta alta tecnología y se puede adaptar a los recursos disponibles, abarcando todas las áreas de conocimiento, y dentro de ellas competencias técnicas o actitudes, solas o en conjunto. El uso racional y basado en evidencia de la simulación es de la mayor importancia por la necesidad de una mayor efectividad y eficiencia en la transformación de los profesionales de la salud para que puedan mejorar su capacidad de atender a los pacientes. La simulación es también una buena herramienta de evaluación de competencias y habilidades en Medicina y otras disciplinas de las Ciencias de la Salud Este manual incluye técnicas y modos de simulación clínica en diversas especialidades médicas, útiles, para quien busque un manual práctico y actualizado.Cátedra de Mecenazgo de la Universidad de Málaga. Cátedra de Terapias Avanzadas en Patología Cardiovascular Cátedra de Mecenazgo de la Universidad de Málaga. Cátedra de Investigación Biomédica Quirón Salu

    Changes in the levels of free sialic acid during ex vivo lung perfusion do not correlate with pulmonary function. Experimental model

    No full text
    Abstract Background Ex vivo lung perfusion (EVLP) constitutes a tool with great research potential due to its advantages over in vivo and in vitro models. Despite its important contribution to lung reconditioning, this technique has the disadvantage of incurring high costs and can induce pulmonary endothelial injury through perfusion and ventilation. The pulmonary endothelium is made up of endothelial glycocalyx (EG), a coating of proteoglycans (PG) on the luminal surface. PGs are glycoproteins linked to terminal sialic acids (Sia) that can affect homeostasis with responses leading to edema formation. This study evaluated the effect of two ex vivo perfusion solutions on lung function and endothelial injury. Methods We divided ten landrace swine into two groups and subjected them to EVLP for 120 min: Group I (n = 5) was perfused with Steen® solution, and Group II (n = 5) was perfused with low-potassium dextran-albumin solution. Ventilatory mechanics, histology, gravimetry, and sialic acid concentrations were evaluated. Results Both groups showed changes in pulmonary vascular resistance and ventilatory mechanics (p < 0.05, Student’s t-test). In addition, the lung injury severity score was better in Group I than in Group II (p < 0.05, Mann–Whitney U); and both groups exhibited a significant increase in Sia concentrations in the perfusate (p < 0.05 t-Student) and Sia immunohistochemical expression. Conclusions Sia, as a product of EG disruption during EVLP, was found in all samples obtained in the system; however, the changes in its concentration showed no apparent correlation with lung function
    corecore