Prótesis mitral mecánica disfuncionante evaluada mediante distintas técnicas de imagen

A 78-year-old woman with mechanical aortic and mitral prostheses presents a mitral prosthetic dysfunction in the context of a transient ischemic attack. This dysfunction consisted of a block in the opening of one of its leaflets due to the presence of intra-prosthetic thrombus. The definitive diagnosis was revealed by surgical intervention after an exhaustive study. We present the different imaging techniques that were used, for the etiological study, prior to the surgery. They include transthoracic and transoesophageal echocardiography, cine-fluoroscopic evaluation and cardiac-CT.Se presenta una mujer de 78 años portadora de doble prótesis mecánica aórtica y mitral en la que, en el contexto de un accidente isquémico transitorio, se descubre una disfunción de la prótesis mitral. Dicha disfunción consistía en falta de apertura de uno de sus discos por la presencia de un trombo intraprotésico. El diagnóstico definitivo lo proporcionó la intervención quirúrgica después de un estudio exhaustivo. Se presentan las distintas técnicas de imagen que se emplearon para el estudio etiológico previo a la cirugía, y que incluyen ecocardiografía transtorácica y transesofágica, escopia con fluoroscopia y cardio-TC

Expression and Function of GABA Receptors in Myelinating Cells

Myelin facilitates the fast transmission of nerve impulses and provides metabolic support to axons. Differentiation of oligodendrocyte progenitor cells (OPCs) and Schwann cell (SC) precursors is critical for myelination during development and myelin repair in demyelinating disorders. Myelination is tightly controlled by neuron-glia communication and requires the participation of a wide repertoire of signals, including neurotransmitters such as glutamate, ATP, adenosine, or gamma-aminobutyric acid (GABA). GABA is the main inhibitory neurotransmitter in the central nervous system (CNS) and it is also present in the peripheral nervous system (PNS). The composition and function of GABA receptors (GABARs) are well studied in neurons, while their nature and role in glial cells are still incipient. Recent studies demonstrate that GABA-mediated signaling mechanisms play relevant roles in OPC and SC precursor development and function, and stand out the implication of GABARs in oligodendrocyte (OL) and SC maturation and myelination. In this review, we highlight the evidence supporting the novel role of GABA with an emphasis on the molecular identity of the receptors expressed in these glial cells and the possible signaling pathways involved in their actions. GABAergic signaling in myelinating cells may have potential implications for developing novel reparative therapies in demyelinating diseases.This work was supported by CIBERNED (CB06/05/0076; CM) and by grants from the Ministry of Economy and Competitiveness, Government of Spain (SAF2016-75292-R and PID2019-109724RB-I00; CM), Basque Government (IT1203-19; CM), CONACYT-Mexico (No. 252121; RA), PAPIIT-UNAM-Mexico (IN203519; RA) and NIH (R21AG053740 and R21MH113177; AL). MS-R was hired thanks to the Gangoiti Foundation (Bilbao). LB-C and RO hold fellowships from Basque Government and CONACYT-Mexico, respectively

Structure démographique et génétique de quatre populations provençales de Pamassius mnemosyne (L.) (Lepidoptera Papilionidae) : isolement et polymorphisme dans des populations « menacées »

This study contributes to the knowledge of macroalgae associated to four habitats at Tuxpan Reef, Veracruz, México. We carried out, 20 sampling in four habitats: grass beds, coral rubble, coralline rock-coral and coralline rock-sea urchin, from April to June 2005. We identified 39 algae species included in 32 genera and 18 families. Among these species, nine were new records for the Tuxpan Reef. The highest richness in terms of the species number was recorded in coral rubble and coralline rock-coral habitats. The differences in the composition and species can beattributedto thetype of substrate and the associated benthos.El presente estudio contribuye al conocimiento de las macroalgas asociadas a cuatro ambientes del arrecife Tuxpan, Veracruz, México. Se efectuaron 20 muestreos en los siguientes hábitats: pastos marinos, restos de coral, roca coralina-corales y roca coralina-erizos, durante el periodo de abril a junio de 2005. Se determinaron 39 especies de macroalgas pertenecientes a 32 géneros y 18 familias. Entre éstas, se citan nueve registros nuevos para el arrecife Tuxpan. La riqueza específica fue más alta en los ambientes de roca coralina-corales y restos de coral. Las diferencias en la composición y el número de especies de macroalgas, se explican por las características del sustrato y el bentos asociado

Near Real-Time Automated Early Mapping of the Perimeter of Large Forest Fires from the Aggregation of VIIRS and MODIS Active Fires in Mexico

In contrast with current operational products of burned area, which are generally available one month after the fire, active fires are readily available, with potential application for early evaluation of approximate fire perimeters to support fire management decision making in near real time. While previous coarse-scale studies have focused on relating the number of active fires to a burned area, some local-scale studies have proposed the spatial aggregation of active fires to directly obtain early estimate perimeters from active fires. Nevertheless, further analysis of this latter technique, including the definition of aggregation distance and large-scale testing, is still required. There is a need for studies that evaluate the potential of active fire aggregation for rapid initial fire perimeter delineation, particularly taking advantage of the improved spatial resolution of the Visible Infrared Imaging Radiometer (VIIRS) 375 m, over large areas and long periods of study. The current study tested the use of convex hull algorithms for deriving coarse-scale perimeters from Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) active fire detections, compared against the mapped perimeter of the MODIS collection 6 (MCD64A1) burned area. We analyzed the effect of aggregation distance (750, 1000, 1125 and 1500 m) on the relationships of active fire perimeters with MCD64A1, for both individual fire perimeter prediction and total burned area estimation, for the period 2012–2108 in Mexico. The aggregation of active fire detections from MODIS and VIIRS demonstrated a potential to offer coarse-scale early estimates of the perimeters of large fires, which can be available to support fire monitoring and management in near real time. Total burned area predicted from aggregated active fires followed the same temporal behavior as the standard MCD64A1 burned area, with potential to also account for the role of smaller fires detected by the thermal anomalies. The proposed methodology, based on easily available algorithms of point aggregation, is susceptible to be utilized both for near real-time and historical fire perimeter evaluation elsewhere. Future studies might test active fires aggregation between regions or biomes with contrasting fuel characteristics and human activity patterns against medium resolution (e.g., Landsat and Sentinel) fire perimeters. Furthermore, coarse-scale active fire perimeters might be utilized to locate areas where such higher-resolution imagery can be downloaded to improve the evaluation of fire extent and impactFunding for this study was provided by CONAFOR/CONACYT Projects “CO2-2014-3-252620” and “CO-2018-2-A3-S-131553” for the development and enhancement of a Forest Fire Danger Prediction System for Mexico, funded by the Sectorial Fund for forest research, development and technological innovation “Fondo Sectorial para la investigación, el desarrollo y la innovación tecnológica forestal”S

Temporal patterns of active fire density and its relationship with a satellite fuel greenness index by vegetation type and region in Mexico during 2003-2014

Background: Understanding the temporal patterns of fire occurrence and their relationships with fuel dryness is key to sound fire management, especially under increasing global warming. At present, no system for prediction of fire occurrence risk based on fuel dryness conditions is available in Mexico. As part of an ongoing national-scale project, we developed an operational fire risk mapping tool based on satellite and weather information. Results: We demonstrated how differing monthly temporal trends in a fuel greenness index, dead ratio (DR), and fire density (FDI) can be clearly differentiated by vegetation type and region for the whole country, using MODIS satellite observations for the period 2003 to 2014. We tested linear and non-linear models, including temporal autocorrelation terms, for prediction of FDI from DR for a total of 28 combinations of vegetation types and regions. In addition, we developed seasonal autoregressive integrated moving average (ARIMA) models for forecasting DR values based on the last observed values. Most ARIMA models showed values of the adjusted coefficient of determination (R2 adj) above 0.7 to 0.8, suggesting potential to forecast fuel dryness and fire occurrence risk conditions. The best fitted models explained more than 70% of the observed FDI variation in the relation between monthly DR and fire density. Conclusion: These results suggest that there is potential for the DR index to be incorporated in future fire risk operational tools. However, some vegetation types and regions show lower correlations between DR and observed fire density, suggesting that other variables, such as distance and timing of agricultural burn, deserve attention in future studiesAntecedentes: Una adecuada planificación del manejo del fuego requiere de la comprensión de los patrones temporales de humedad del combustible y su influencia en el riesgo de incendio, particularmente bajo un escenario de calentamiento global. En la actualidad en México no existe ningún sistema operacional para la predicción del riesgo de incendio en base al grado de estrés hídrico de los combustibles. Un proyecto de investigación nacional actualmente en funcionamiento, tiene como objetivo el desarrollo de un sistema operacional de riesgo y peligro de incendio en base a información meteorológica y de satélite para México. Este estudio pertenece al citado proyecto Resultados: Se observaron en el país distintas tendencias temporales en un índice de estrés hídrico de los combustibles basado en imágenes MODIS, el índice “dead ratio” (DR), y en las tendencias temporales de un ìndice de densidad de incendios (FDI), en distintos tipos de vegetación y regiones del país. Se evaluaron varios modelos lineales y potenciales, incluyendo términos para la consideración de la autocorrelación temporal, para la predicción de la densidad de incendios a partir del índice DR para un total de 28 tipos de vegetación y regiones. Se desarrollaron además modelos estacionales autoregresivos de media móvil (ARIMA en inglés) para el pronóstico del índice DR a partir de los últimos valores observados. La mayoría de los modelos ARIMA desarrollados mostraron valores del coeficiente de determinación ajustado (R2 adj) por encima de 0.7 to 0.8, sugiriendo potencial para ser empleados para un pronóstico del estrés hídrico de los combustibles y las condiciones de riesgo de ocurrencia de incendio. Con respecto a los modelos que relacionan los valores mensuales de DR con FDI, la mayoría de ellos explicaron más del 70% de la variabilidad observada en FDI. Conclusiones: Los resultados sugirieron potencial del índice DR para ser incluido en futuras herramientas operacionales para determinar el riesgo de incendio. En algunos tipos de vegetación y regiones se obtuvieron correlaciones más reducidas entre el índice DR y los valores observados de densidad de incendios, sugiriendo que el papel de otras variables tales como la distancia y el patrón temporal de quemas agrícolas debería ser explorado en futuros estudiosFunding for this work was provided by CONAFOR-CONACYT Project 252620 “Development of a Fire Danger System for Mexico.” This work was also cofinanced by the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria and European Social Fund (Dr. E. Jiménez grant)S

31 visiones actuales de la transparencia

Treinta y una aportaciones de autores nacionales y extranjeros sobre la transparencia de las instituciones públicas y de los sujetos obligados por la Ley 19/2013 de 9 de diciembre y el derecho de acceso a la información pública

Estudios culturales : prácticas diversas, enfoques pluralistas

1 archivo PDF (294 páginas) : incluye ilustracionesDesde el ámbito de los estudios culturales plantea un acercamiento teórico y metodológico multidisciplinar en el que a partir de la reflexión y el estudio de casos se analizan problemáticas reales de la historia de la cultura mexicana. Ciencia y humanismo, empirismo y reflexión son las caras de la moneda de una tendencia epistemológica que en las últimas décadas se ha planteado en el ámbito de la investigación sociológica y antropológica bajo el marbete de estudios culturales, con el objetivo de aprehender el complejo funcionamiento de los procesos culturales en las sociedades modernas. Recoge colaboraciones que abordan aspectos esenciales en el debate sobre los estudios culturales como el estado de las instituciones y la acción política, los exilios, desexilios y los movimientos migratorios entre México y Estados Unidos y sus influencias en la adaptación de los migrantes a ambos lados de la frontera, la problemática de la sexualidad y las formas de violencia, el tratamiento de la enfermedad y de la muerte, la crisis socioeconómica, el incipiente debate sobre las culturas digitales o la conciencia ecológica y medioambiental en el México de hoy. En primer lugar encontramos cuatro textos que analizan la problemática de la migración en México desde cuatro perspectivas distintas. Ana Ochoa O’Leary analiza las nuevas perspectivas de la movilización política en el sur de Estados Unidos ante los graves problemas de adaptación de los migrantes derivados de las decisiones legislativas de los últimos gobiernos nacionales y federales estadounidenses. Adriana María Eugenia Cabrera destaca la influencia de los movimientos migratorios en el patrimonio cultural de las zonas afectadas a través del estudio del proceso de identidad social del migrante y su intensa relación con los edificios históricos. También en el culto a las imágenes hay una influencia evidente del fenómeno de la migración, como muestran Pablo Martínez y María del Refugio Piña en el caso de los exvotos donados al Niño de Atocha. Política, arquitectura, antropología y también la literatura como paradigma de la migración en el trabajo de Teresita Quiroz sobre los movimientos migratorios hacia la ciudad de México en la narrativa de Mariano Azuela. El segundo apartado recoge colaboraciones bajo el epígrafe “Narratividad, discursos e identidades” en el que se mezclan perspectivas de configuración de identidades en el periodo virreinal en el estudio de Beatriz Aracil sobre el viaje de Cortés a la Mar del Sur y la transformación del sujeto colonial y reflexiones sobre lo hispano en pleno proceso de Independencia durante las primeras décadas del siglo XIX a través de artículos y monografías de Anselmo Portilla y Niceto Zamaçois planteadas por Alfredo Moreno Flores. El viaje continúa con el trabajo de Blanca Estela López y José Silvestre Revueltas sobre la narratividad para juegos y rituales, que antecede a las reflexiones literarias de Daniel Santillán sobre la identidad nacional en Margarita de Niebla, de Jaime Torres Bodet y el acercamiento a la mujer mexicana del xix a través de las referencias literarias a la lencería en cuatro autores de la época que plantea Margarita Alegría. El apartado concluye con análisis del viaje de escritores diplomáticos del XIX en China propuesto por María Fernanda García de los Arcos. “Justicia, ciudadanos y luchas sociales” propone una reflexión histórica sobre el sistema judicial y el estado de las cárceles mexicanas a partir del estudio de María Elvira Buelna y Antonio Salcedo Flores y dos ejemplos de articulación ciudadana y lucha social en los estudios de Marta Ochman y Reyna Sánchez Estévez. “Imágenes, redes y fotoperiodismo” refleja la importancia de la imagen en la sociología contemporánea y su revalorización en el estudio de textos histórico-literarios como el Diario de guerra de Simone de Beauvoir que plantea Ma. Eugenia Rabadán Villalpando y en el contexto musical hardcorero del trabajo de José A. Trejo Sánchez, que destaca la importancia de la conexión en red como emblema de pertenencia a un grupo social entre los jóvenes artistas del Valle de Toluca. “Discapacidad y muerte” enfrenta un problema crucial entre los jóvenes indígenas en Chiapas: el suicidio, a propuesta de Jorge Magaña Ochoa y debate la asistencia a niños con Síndrome de Down en el México contemporáneo en el estudio de Janeth Rojas Contreras. José Carlos Vizuete Mendoza reflexiona en el apartado “Iglesias” sobre la evolución centralizadora y descentralizadora de la estructura de gobierno, los rituales de culto, el calendario festivo y la lengua de la liturgia cristiana. Para concluir, Judith Catalina Navarro Gómez presenta en “Energía y Medio Ambiente” la problemática energética en el mundo contemporáneo y unas pautas para mejorar el medio ambiente a partir de una nueva cultura de la energía y Martha Eugenia Rodríguez y Jimena Pérez plantean un estudio de la conciencia ambiental en la ciudad de México en tres momentos históricos: siglo XVIII, siglo XIX y siglo XX y su repercusión en la salud pública

Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI : Results of the ISACS-STEMI COVID-19 Registry

Background: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March–June 2019 and 2020. Patients were divided according to age (< or ≥75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825–0.861, p < 0.0001). We found a significant agerelated reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24–1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05–1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic

Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry

Background: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March-June 2019 and 2020. Patients were divided according to age (= 75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825-0.861, p < 0.0001). We found a significant age-related reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24-1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05-1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic

Gender Difference in the Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry

Background. Several reports have demonstrated the impact of the COVID-19 pandemic on the management and outcome of patients with ST-segment elevation myocardial infarction (STEMI). The aim of the current analysis is to investigate the potential gender difference in the effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI patients within the ISACS-STEMI COVID-19 Registry. Methods. This retrospective multicenter registry was performed in high-volume primary percutaneous coronary intervention (PPCI) centers on four continents and included STEMI patients undergoing PPCIs in March–June 2019 and 2020. Patients were divided according to gender. The main outcomes were the incidence and timing of the PPCI, (ischemia time ≥ 12 h and door-to-balloon ≥ 30 min) and in-hospital or 30-day mortality. Results. We included 16683 STEMI patients undergoing PPCIs in 109 centers. In 2020 during the pandemic, there was a significant reduction in PPCIs compared to 2019 (IRR 0.843 (95% CI: 0.825–0.861, p < 0.0001). We did not find a significant gender difference in the effects of the COVID-19 pandemic on the numbers of STEMI patients, which were similarly reduced from 2019 to 2020 in both groups, or in the mortality rates. Compared to prepandemia, 30-day mortality was significantly higher during the pandemic period among female (12.1% vs. 8.7%; adjusted HR [95% CI] = 1.66 [1.31–2.11], p < 0.001) but not male patients (5.8% vs. 6.7%; adjusted HR [95% CI] = 1.14 [0.96–1.34], p = 0.12). Conclusions. The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures similarly observed in both genders. Furthermore, we observed significantly increased in-hospital and 30-day mortality rates during the pandemic only among females. Trial registration number: NCT 04412655