High density culturing of porcine hepatocytes immobilized on nonwoven polyurethane-based biomatrices

Objective: Hepatocytes are increasingly used as functional units in bioartificial liver devices. The objective of the present study was to investigate the feasibility of culturing porcine hepatocytes in high density on a novel polyurethane-based nonwoven three-dimensional matrix. We investigated (1) the optimal cell density within this culture configuration, (2) the maintenance of liver-specific morphology and cell functions over long-term periods and (3) the necessity to apply an additional extracellular matrix component (collagen gel). Methods: Nonwoven polyurethane matrices were manufactured by a specially developed fiber extrusion technology. Pig hepatocytes were cultured at various cell densities of 0.1, 0.25, 0.5, 0.75, 1 and 2 x 10(6) cells/cm(2) on three-dimensional networks of nonwoven polyurethane matrices and cell adhesion as well as functional parameters (DNA of nonattached/attached cells, lactate dehydrogenase release and cytochrome P450 activity) were determined. To assess the performance of cells within this configuration albumin and urea excretion was measured over 8 days. The potentially beneficial effect of an additional extracellular matrix configuration was evaluated by comparing the average albumin synthesis in groups of identical cell numbers. Results: The optimal cell density in this three-dimensional culture configuration was 1 x 10(6) cells/cm(2). The functional capacity of hepatocytes was stable for 8 days at an average level of 53.7 +/- 5.6 ng/h/mug DNA and of 1.8 +/- 0.14 mug/h/mug DNA for albumin and urea excretion, respectively. The supplementation of an extracellular matrix configuration did not improve functional activity of cells. Average albumin synthesis was 35.6 ng/h/mug DNA (28.7, 42.8) and 32.7 ng/h/mug DNA (23.4, 49.2) for collagen-immobilized and control cultures, respectively, Conclusion: The results of the study indicate that nonwoven polyurethane sheets supply a biocompatible support structure for functionally active high density cultures. Thus, nonwoven polyurethane matrices should be further investigated on with respect to their role in the development, optimization and design of bioartificial liver systems. Copyright (C) 2001 S.Karger AG, Basel

Aplicación web para fortalecer la simulación de exámenes de ingreso a la educación superior del ecuador de la academia “Megapro S.A.”, haciendo uso de un modelo bass (Backend As A Service)

Desarrollar una aplicación web educativa para la simulación de exámenes de ingreso a la Educación Superior en la academia “Megapro S.A.”, haciendo uso de un modelo BaaS (Backend as a Service).El presente proyecto tiene como finalidad detallar la construcción de una aplicación web enfocada en la simulación de exámenes para el ingreso a la educación superior en el Ecuador, aplicado en la academia Megapro de la ciudad de Guayaquil, con el fin de centralizar información, realizar seguimientos a estudiantes y optimizar el tiempo que conlleva realizar estas tareas. En la introducción se define los principales aspectos de este proyecto como son: planteamiento del problema, objetivos, alcances, tecnologías, metodologías y otros temas importantes que se extienden en los 3 capítulos que tiene este proyecto. En el primer capítulo se presenta un marco teórico referente a los temas que envuelve este proyecto tales como son: la Educación Superior y netamente temas tecnológicos con respecto al Backend as a Service y Firebase, que son las herramientas principales para el desarrollo de la aplicación. En el segundo capítulo se detalla todo el proceso de análisis, desarrollo y puesta en producción de la aplicación utilizando la metodología Scrum, para cada iteración del proyecto se presenta un análisis y las restricciones que se presentaron al implementar las funcionalidades de las historias de usuario levantadas, esto debido a que no se hace uso de un backend personalizado. En el tercer capítulo se realiza la validación de resultados aplicando un cuestionario SUS para obtener indicadores de usabilidad de la aplicación enfocada en la ISO/IEC 25010, para el correcto análisis de los resultados también se usa el alfa de Cronbach que mide la fiabilidad del cuestionario aplicado.Ingenierí

Characterization of a functional C3A liver spheroid model

More predictive in vitro liver models are a critical requirement for preclinical screening of compounds demonstrating hepatotoxic liability. 3D liver spheroids have been shown to have an enhanced functional lifespan compared to 2D monocultures; however a detailed characterisation of spatiotemporal function and structure of spheroids still needs further attention before widespread use in industry. We have developed and characterized the structure and function of a 3D liver spheroid model formed from C3A hepatoma cells. Spheroids were viable and maintained a compact in vivo-like structure with zonation features for up to 32 days. MRP2 and Pgp transporters had polarised expression on the canalicular membrane of cells in the spheroids and were able to functionally transport CMFDA substrate into these canalicular structures. Spheroids expressed CYP2E1 and were able to synthesise and secrete albumin and urea to a higher degree than monolayer C3A cultures. Penetration of doxorubicin throughout the spheroid core was demonstrated. Spheroids showed increased susceptibility to hepatotoxins when compared to 2D cultures, with acetaminophen having an IC50 of 7.2 mM in spheroids compared to 33.8 mM in monolayer culture. To conclude, we developed an alternative method for creating C3A liver spheroids and demonstrated cellular polarisation and zonation, as well as superior liver-specific functionality and more sensitive toxicological response compared to standard 2D liver models, confirming a more in vivo-like liver model

A Bail Out Solution for an Urgent Situation: Endovascular Exclusion and Embolization of an Infected Femoral Pseudoaneurysm

Purpose: The aim of this study is to show the utility of the combination of thrombin and endograft to solve an urgent situation related to femoral infections. Case: We present the case of a 91-year-old female patient who underwent a femoral endarterectomy and superficial femoral artery angioplasty and developed a surgical site infection. She was readmitted to the hospital because of bleeding and was operated to suture the femoral patch and to do a plasty of sartorius muscle. Six days after the last intervention a femoral pulsatile mass was noted, and the computed tomography showed a big femoral pseudoaneurysm. Taken again to the theater and via a contralateral puncture a viabahn covered endograft was deployed from the external iliac artery to the yet diseased but patent femoral superficial femoral artery and the pseudoaneurysm was punctured, emptied, and filled with thrombin. The patient was discharged 2 weeks after the last procedure and lived for 10 months (she died because of a nonvascular related cause) with a patent graft and with healed lesions. Conclusions: In this case the endovascular solution was a definitive solution in a very old patient with several comorbidities

De la agricultura familiar campesina a las microempresas de monocultivo. Reestructura socio-territorial en la Sierra norte del Ecuador.

In the rural communities of the Parish of González Suárez and Ayora of the Province of Imbabura and Pichincha, respectively, a large number of employees who managed to accumulate capital have decided to become micro-entrepreneurs of strawberry monocultures. This change in the use of the land has caused a socio-territorial restructuring provoking in the communities; environmental, sociocultural and economic impacts, thus generating a set of tensions on the vision of the land, territory and natural resources. This has opened reflections on productivity and profit, on the practice of community values ​​and the sense of peasant family agriculture for indigenous communities. And, considering that the monoculture has irreversible effects on the land, they put into the debate the urgent need to incorporate in the agenda of the organizations and the indigenous movement the demand for the construction of sustainable rural territories, together with the State and the authorities local.En las comunidades rurales de las Parroquia González Suárez y Ayora de las Provincia de Imbabura y Pichincha, respectivamente, gran cantidad de asalariados que lograron acumular capital han decidido convertirse en microempresarios de monocultivos de frutillas. Este cambio en el uso de la tierra ha ocasionado una reestructuración socioterritorial provocando en las comunidades; impactos ambientales, socioculturales y económicos, generado así, un conjunto de tensiones sobre la visión de la tierra, el territorio y los recursos naturales. Esto ha abierto reflexiones sobre la productividad y la ganancia, sobre la práctica de valores comunitarios y el sentido de la agricultura familiar campesina para las comunidades indígenas. Y, considerando que el monocultivo tiene afectaciones irreversibles en la tierra, ponen en el debate la necesidad apremiante de incorporar en la agenda de las organizaciones y del movimiento indígena la exigencia de la construcción de territorios rurales sostenibles, en conjunto con el Estado y las autoridades locales

Optimización de la confiabilidad mediante la reconfiguración de circuitos primarios en la subestación Quevedo de CNEL EP. Unidad de negocio Santo Domingo.

This research work deals with the reliability analysis in the feeders belonging to the Quevedo substation of CNEL EP, in order to establish the circuits with the highest number of electrical power interruptions to submit them to a reconfiguration analysis, using historical data from the last three years, where Pareto analysis is used to determine the percentage of interruptions that most affect each feeder. As a starting point, the information is classified by type of failure and duration, to determine the rate of failure and repair, availability (A) and unavailability (U) of the feeders, data with which it is possible to calculate the failure rates. reliability. From these results, the reconfiguration of circuit 6 is analyzed, since it presents the lowest indices. Using the Monte Carlo simulation in the MATLAB software package, it will be possible to determine the failure times and repair times in each section of the feeder. Applying the theory of graphs, the section with failure (disconnected) and the possible reconnection from neighboring nodes are determined, considering as a restriction the chargeability of the lines, that the repair time is less than the maneuvering time for a possible reconnection. This will allow new reliability indices to be calculated before and after reconfiguration during a prudent analysis time, allowing the optimal path to be identified.El presente trabajo de investigación trata sobre el análisis de confiabilidad en los alimentadores pertenecientes a la subestación Quevedo de CNEL EP, con el fin de establecer los circuitos con mayor número de interrupciones de energía eléctrica para someterlos a un análisis de reconfiguración, utilizando datos históricos de los tres últimos años, donde se utiliza el análisis de Pareto para determinar el porcentaje de interrupciones que más inciden en cada alimentador. Como punto de partida se clasifica la información por tipo de falla y duración, para determinar la tasa de falla y reparación, disponibilidad (A) e indisponibilidad (U) de los alimentadores, datos con los cuales es posible realizar el cálculo de los índices de confiabilidad. De estos resultados se analiza la reconfiguración del circuito 6, ya que presenta los índices más bajos. Mediante la simulación de Monte Carlo en el paquete informático de MATLAB, se podrá determinar los tiempos de falla y tiempos de reparación en cada tramo del alimentador. Aplicando la teoría de grafos se determina el tramo con falla (desconectado) y la posible reconexión desde los nodos vecinos, considerando como restricción la cargabilidad de las líneas, que el tiempo de reparación sea menor al tiempo de maniobra para una posible reconexión. Esto permitirá calcular nuevos índices de confiabilidad antes y después de la reconfiguración durante un tiempo prudente de análisis, permitiendo identificar la ruta óptima

Desarrollo de un dispositivo IoT para el invernadero de la Asociación de Mujeres Productoras Agroecológicas de Cangahua

El desconocimiento de factores como la humedad relativa del suelo y la temperatura ambiente ha sido una problemática al momento de cultivar en el invernadero AMPAC, ya que estos son factores que inciden directamente en su producción, por lo cual se propuso el desarrollo de un dispositivo IoT para el mejoramiento de la producción de brócoli, cebolla, pepino, pimiento y tomate, este dispositivo posee un módulo ESP32 y sensores que permiten la adquisición y visualización de datos como; temperatura ambiente y humedad relativa del suelo tiempo real, estos datos son enviados al servidor de Adafruit IO en la nube y se almacenan en su base de datos, también el dispositivo permite tener el control de electroválvulas, focos y un ventilador, además con el uso de Android Studio se desarrolló una aplicación que posibilita a la persona a cargo el monitoreo de los parámetros de forma remota, de esta manera se pueden reducir los traslados del personal encargado al invernadero AMPAC, finalmente con la vinculación del servicio IFTTT se envían mensajes de alerta cuando los parámetros de humedad y temperatura hayan salido de su rango, de manera que el encargado del invernadero AMPAC pueda usar esta información y tomar las acciones necesarias en bienestar del cultivo.The lack of knowledge of factors such as relative soil humidity and ambient temperature has been a problem when growing in the AMPAC greenhouse, since these are factors that directly affect their production, so it was proposed the development of an IoT device for the improvement of the production of broccoli, onion, cucumber, bell pepper and tomato, this device has an ESP32 module and sensors that allow the acquisition and visualization of data such as; These data are sent to the Adafruit IO server in the cloud and stored in its database. The device also allows the control of solenoid valves, spotlights and a fan, and with the use of Android Studio an application was developed that enables the person in charge to monitor the parameters remotely, Finally, with the linking of the IFTTT service, alert messages are sent when the humidity and temperature parameters have gone out of range, so that the person in charge of the AMPAC greenhouse can use this information and take the necessary actions for the welfare of the crop

Nitric oxide overproduction by cue1 mutants differs on developmental stages and growth conditions

The cue1 nitric oxide (NO) overproducer mutants are impaired in a plastid phosphoenolpyruvate/phosphate translocator, mainly expressed in Arabidopsis thaliana roots. cue1 mutants present an increased content of arginine, a precursor of NO in oxidative synthesis processes. However, the pathways of plant NO biosynthesis and signaling have not yet been fully characterized, and the role of CUE1 in these processes is not clear. Here, in an attempt to advance our knowledge regarding NO homeostasis, we performed a deep characterization of the NO production of four different cue1 alleles (cue1-1, cue1-5, cue1-6 and nox1) during seed germination, primary root elongation, and salt stress resistance. Furthermore, we analyzed the production of NO in different carbon sources to improve our understanding of the interplay between carbon metabolism and NO homeostasis. After in vivo NO imaging and spectrofluorometric quantification of the endogenous NO levels of cue1 mutants, we demonstrate that CUE1 does not directly contribute to the rapid NO synthesis during seed imbibition. Although cue1 mutants do not overproduce NO during germination and early plant development, they are able to accumulate NO after the seedling is completely established. Thus, CUE1 regulates NO homeostasis during post-germinative growth to modulate root development in response to carbon metabolism, as different sugars modify root elongation and meristem organization in cue1 mutants. Therefore, cue1 mutants are a useful tool to study the physiological effects of NO in post-germinative growth

Modeling human liver biology using stem cell-derived hepatocytes

Stem cell-derived hepatocytes represent promising models to study human liver biology and disease. This concise review discusses the recent progresses in the field, with a focus on human liver disease, drug metabolism and virus infection