Epithelial cells removed in advanced surface ablation (ASA) surgery can be used as a source of corneal samples to perform in vitro studies

Producción CientíficaHuman corneal epithelial cells are needed to study corneal pathophysiology in vitro. Due to the limitations of cell lines, the use of primary cells is highly desirable, but the scarcity of human tissues, along with ethical issues, make it difficult to accomplish all required experiments. In advanced surface ablation (ASA), the central corneal epithelium is removed and discarded. We hypothesized that ASA samples could be used to perform in vitro assays. In this study, 29 samples from patients undergoing ASA were recovered in supplemented DMEM/F12 culture medium, RIPA buffer, or RLT lysis buffer. The first aim was to determine whether cells could be maintained in culture. Although with the explant technique, tissue pieces did not attach to the culture surface, after disaggregation, cells showed high viability (90.0 ± 6.0%), attached to plates, and remained viable for up to 14 days. The second aim was to elucidate if ASA samples could be used to study protein or gene expression. Cytokeratin-3, ZO-1, Ki67, and E-cadherin protein expression were confirmed by immunofluorescence. Total protein (485.8 ± 115.8 μg) was isolated from cells in RIPA buffer, and GAPDH was detected by Western blotting, indicating that samples are adequate for protein studies. RNA (9.0 ± 3.6 μg) was isolated from samples in RLT lysis buffer, and GAPDH gene expression was studied by PCR, confirming that samples were also suitable for gene expression studies. These results suggest that samples obtained from corneal surface ablation procedures may constitute a valuable source of human cells to accomplish in vitro studies.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project FEDER-CICYT MAT2013-47501-C02-R)Ministerio de Ciencia, Innovación y Universidades - Fondo Europeo de Desarrollo Regional (project RTI2018-094071-B-C21

Simulador para la enseñanza de la planificación dinámica de instrucciones

El presente trabajo ilustra el desarrollo y utilización de un simulador para la enseñanza de la gestión dinámica de instrucciones en un procesador segmentado a alumnos de cuarto curso de Ingeniería Informática. El objetivo de dicho simulador es facilitar la comprensión del algoritmo de Tomasulo y del hardware necesario para su implementación y funcionamiento, así como proporcionar la posibilidad de visualizar el estado del procesador (instrucción en cada etapa, bancos de registros de enteros y de coma flotante, estaciones de reserva, memoria, etc.) al final de cada uno de los ciclos de reloj necesarios para la ejecución de un determinado conjunto de instrucciones. Este simulador se utiliza en las prácticas de la asignatura de Arquitectura de Computadores II de la titulación de Ingeniero de Informática de la UPV

High-power UV-LED degradation: Continuous and cycled working condition influence

High-power (HP) UV-LEDs can replace UV lamps for real-time fluoro-sensing applications by allowing portable and autonomous systems. However, HP UV-LEDs are not a mature technology, and there are still open issues regarding their performance evolution over time. This paper presents a reliability study of 3W UV-LEDs, with special focus on LED degradation for two working conditions: continuous and cycled (30 s ON and 30 s OFF). Accelerated life tests are developed to evaluate the influence of temperature and electrical working conditions in high-power LEDs degradation, being the predominant failure mechanism the degradation of the package. An analysis that includes dynamic thermal and optical HP UV-LED measurements has been performed. Static thermal and stress simulation analysis with the finite element method (FEM) identifies the causes of package degradation. Accelerated life test results prove that HP UV-LEDs working in cycled condition have a better performance than those working in continuous condition

Enseñanza de Mecanismos Hardware de Ejecución Especulativa de Instrucciones

El presente trabajo describe la metodología empleada en las prácticas de cuarto curso de la Facultad de Informática para la enseñanza y aplicación de mecanismos hardware de especulación de instrucciones basados en el algoritmo de Sohi. Debido a la complejidad de dichos mecanismos y a la imposibilidad de trabajar directamente con ellos, se ha desarrollado un sistema que permite al alumno realizar su propia implementación del algoritmo de Sohi, simular su funcionamiento en la ejecución de programas y, además, detectar de forma automática los posibles errores de ejecución debidos a una implementación incorrecta. El objetivo del sistema es facilitar la comprensión del algoritmo de ejecución especulativa. Para ello, gracias a la detección automática de fallos, al alumno se le proporciona de forma precisa dónde y cuándo está fallando su desarrollo, lo cual le permite rectificarlo. Esta realimentación es la principal ventaja del sistema utilizado pues implica llegar a entender bien el algoritmo de Sohi para así conseguir su correcto funcionamiento

Immunomodulatory properties of the protein fraction from Phorphyra columbina

The phycobiliproteins from Rhodophyta, R-phycoerythrin (R-PE) and C-phycocyanin (C-PC), have been shown to exert immunomodulatory effects. This study evaluated the effects of a Phorphyra columbina protein fraction (PF) and R-PE and C-PC on rat primary splenocytes, macrophages, and T-lymphocytes in vitro. PF featured various protein species, including R-PE and C-PC. PF showed mitogenic effects on rat splenocytes and was nontoxic to cells except at 1 g L-1 protein. IL-10 secretion was enhanced by PF in rat splenocytes, macrophages, and especially T-lymphocytes, whereas it was markedly diminished by R-PE and C-PC. The production of pro-inflammatory cytokines by macrophages was inhibited. The effect of PF on IL-10 was evoked by JNK/p38 MAPK and NF-κB-dependent pathways in macrophages and T-lymphocytes. It was concluded that PF has immunomodulatory effects on macrophages and lymphocytes that appear to be predominantly anti-inflammatory via up-regulated IL-10 production and cannot be accounted for by R-PE and C-PC.Fil: Cian, Raúl Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López Posadas, Rocío. Universidad de Granada; EspañaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sánchez De Medina, Fermín. Universidad de Granada; EspañaFil: Martínez Augustin, Olga. Universidad de Granada; Españ

Elimination of scan impedance anomalies in ultra-wide band phased arrays of differentially fed tapered slot antenna elements

Scan impedance anomalies are associated to phased arrays. There are different phenomena in order to explain these scan blindnesses produced when the array scans at one frequency and one angle. The most popular technique for eliminating these scan blindnesses is based on the use of electric walls in the grid of the two dimensional array. In this paper we present a dual polarized ultra-wide band array based on “bunny ears” antennas from 0.3 GHz to 1 GHz which presents scan blindness. We analyze the cause of the anomaly and present a technique non based on electric walls in order to avoid the scan blindness with a small increase in the noise figure of the array

Impact of Epithelial Cell Shedding on Intestinal Homeostasis

The gut barrier acts as a first line of defense in the body, and plays a vital role in nutrition and immunoregulation. A layer of epithelial cells bound together via intercellular junction proteins maintains intestinal barrier integrity. Based on a tight equilibrium between cell extrusion and cell restitution, the renewal of the epithelium (epithelial turnover) permits the preservation of cell numbers. As the last step within the epithelial turnover, cell shedding occurs due to the pressure of cell division and migration from the base of the crypt. During this process, redistribution of tight junction proteins enables the sealing of the epithelial gap left by the extruded cell, and thereby maintains barrier function. Disturbance in cell shedding can create transient gaps (leaky gut) or cell accumulation in the epithelial layer. In fact, numerous studies have described the association between dysregulated cell shedding and infection, inflammation, and cancer; thus epithelial cell extrusion is considered a key defense mechanism. In the gastrointestinal tract, altered cell shedding has been observed in mouse models of intestinal inflammation and appears as a potential cause of barrier loss in human inflammatory bowel disease (IBD). Despite the relevance of this process, there are many unanswered questions regarding cell shedding. The investigation of those mechanisms controlling cell extrusion in the gut will definitely contribute to our understanding of intestinal homeostasis. In this review, we summarized the current knowledge about intestinal cell shedding under both physiological and pathological circumstances

Medidas de propiedades dieléctricas de materiales de construcción utilizando una guía rectangular

A set of measurements of electromagnetic properties of building materials is presented in this work. The method is based on an open-ended rectangular waveguide that radiates into the material under study. Measurements were done by using two waveguides with different size for obtaining the results in two ranges of frequencies. The values of the dielectric constant are deduced from the measured reflection coefficient or admittance of the waveguide radiating into the material. A relatively simple model can be used to deduce the values of the dielectric constant from the experimental data. This method can be used for other type of materials and its main advantage is the non-destructive character and the ease implementation

Reconstrucción ósea acetabular con cotilos no cementados y aporte de aloinjerto en la artroplastia total de cadera : estudio de 35 casos

Se han revisado 35 arlroplastias realizadas en 29 pacientes portadores de algún tipo de defecto óseo en el cotilo por fallo de prótesis total de cadera. En el presente estudio incluimos sólo las reconstrucciones acetabulares efectuadas con implantes no cementados. La edad media fue de 60 años (29/79), siendo 19 mujeres y 10 varones. Clasificamos los defectos óseos siguiendo a D'Antonio en segmentarios, cavitarios y mixtos, y para la reparación de dichos defectos utilizamos aloinjerto criopreservado en todos los casos excepto uno, tratado con injerto liofilizado. Valoramos los resultados desde un punto de vista clínico, subjetivo y objetivo (escala de Harris). Desde un punto de vista radiológico se analizaron las migraciones del implante acetabular, la existencia de zonas de radiolucencia, las osificaciones periarticulares y la incorporación o no del injerto óseo utilizado. Desde el punto de vista clínico obtuvimos un 60% de resultados excelentes y buenos, frente a un 40% de regulares y malos. Desde cualquier punto de vista el índice de aflojamiento del componente acetabular fue mucho mayor que el que puede obtenerse con cotilos no defectuososThirty five revision hip arthroplasties performed in 29 patients with acetabular bone defects were reviewed. In this series we only include the acetabular reconstruction performed using non cemented acetabular implants. The mean age of the patients was 60 years (29-79), 19 were female and 10 male. We classified the acetabular bone defects according to D'Antonio, in segmentary, cavitary and combined. To repair these defects, we used criopreserved allograft, except one case in which a liofilized allograft was used. The results were evaluated clinically (modified Harris hip score) and radiographically, looking for acetabular migrations, radiolucent lines, periarticular ossifications and bone graft incorporation. We obtained 60% of excellent and good results. There was 40% of poor and fair results. The acetabular loosening rate was higher than in revision hip arthroplasty without acetabular bone defects