Thyroid Hormone-Induced Cytosol-to-Nuclear Translocation of Rat Liver Nrf2 Is Dependent on Kupffer Cell Functioning

L-3,3′,5-triiodothyronine (T3) administration upregulates nuclear factor-E2-related factor 2 (Nrf2) in rat liver, which is redox-sensitive transcription factor mediating cytoprotection. In this work, we studied the role of Kupffer cell respiratory burst activity, a process related to reactive oxygen species generation and liver homeostasis, in Nrf2 activation using the macrophage inactivator gadolinium chloride (GdCl3; 10 mg/kg i.v. 72 h before T3 [0.1 mg/kg i.p.]) or NADPH oxidase inhibitor apocynin (1.5 mmol/L added to the drinking water for 7 days before T3), and determinations were performed 2 h after T3. T3 increased nuclear/cytosolic Nrf2 content ratio and levels of heme oxygenase 1 (HO-1), catalytic subunit of glutamate cysteine ligase, and thioredoxin (Western blot) over control values, proteins whose gene transcription is induced by Nrf2. These changes were suppressed by GdCl3 treatment prior to T3, an agent-eliciting Kupffer-cell depletion, inhibition of colloidal carbon phagocytosis, and the associated respiratory burst activity, with enhancement in nuclear inhibitor of Nrf2 kelch-like ECH-associated protein 1 (Keap1)/Nrf2 content ratios suggesting Nrf2 degradation. Under these conditions, T3-induced tumor necrosis factor-α (TNF-α) response was eliminated by previous GdCl3 administration. Similar to GdCl3, apocynin given before T3 significantly reduced liver Nrf2 activation and HO-1 expression, a NADPH oxidase inhibitor eliciting abolishment of colloidal carbon-induced respiratory burst activity without altering carbon phagocytosis. It is concluded that Kupffer cell functioning is essential for upregulation of liver Nrf2-signaling pathway by T3. This contention is supported by suppression of the respiratory burst activity of Kupffer cells and the associated reactive oxygen species production by GdCl3 or apocynin given prior to T3, thus hindering Nrf2 activation

Ortodoncia preventiva e interceptiva: Manejo de mordida abierta anterior y pérdida dental prematura

Antecedentes: El enfoque actual del tratamiento odontopediátrico, implica una visión holística con un manejo integral y multidisciplinario. Considera múltiples factores, bajo un enfoque de riesgo cariogénico con seguimiento del crecimiento y desarrollo craneofacial. Cuando hay compromiso funcional y estético se debe considerar un tratamiento preventivo, rehabilitador y con ortodoncia preventiva e interceptiva.Presentación clínica: Niña de 9 años atendida en la Facultad de Odontología - Universidad de Chile. Al examen clínico presenta dentición mixta, en actividad de caries con alto riesgo cariogénico, Clase I de Angle con mordida abierta anterior dentoalveolar por hábito de succión no nutritiva, dedo e interposición lingual en reposo y deglución. El tratamiento implicó la exodoncia prematura de un segundo molar primario, para conservar el espacio se colocó un mantenedor fijo de arco lingual como ortodoncia preventiva. Con el objetivo de evitar la interposición, reeducar la lengua y recuperar la pérdida de crecimiento transversal del maxilar se realizó ortodoncia interceptiva con un expansor maxilar con rejilla palatina.Relevancia clínica: El manejo terapeútico de las anomalías dentoalveolares es una competencia a ser realizada por el odontólogo general. Para el éxito es fundamental el diagnóstico precoz y una planificación clínica oportuna. Son tratamientos de resolución rápida y un factor clave es el control periódico.Conclusión: En este caso clínico, el manejo del espacio dentario y mordida abierta anterior dentoalveolar, evitó una subsecuente alteración secundaria esqueletal mejorando el pronóstico de la anomalia dentoalveolar

First Record of Testate Amoebae on Glaciers and Description of a New Species Puytoracia jenswendti nov. sp. (Rhizaria, Euglyphida)

This study documents for the first time the presence of testate amoebae on glaciers. Three shallow firn cores of 10 m depth were obtained from the Mocho-Choshuenco and Osorno volcanoes, Southern Andes, Chile, in October and November, 2005. Euglyphid testate amoebae were detected in 28 samples that correspond to the spring-summer layers of the firn cores. Inspection of 454 collected individuals reveals the presence of four different taxa. Three of these taxa, Trinema lineare, Trinema enchelys and Puytoracia bergeri have previously been reported in ice-free environments. The fourth taxon corresponds to a new species Puytoracia jenswendti nov. sp. The observation of food content and reproductive activities in a significant fraction of specimens evidence that testate amoebae are competent to inhabit glaciers. The testate amoebae found in the firn cores display clear seasonal variations in abundance indicating that these records can provide a new and novel proxy as paleoindicator for firn/ice core dating and for estimation of past glacier mass balance

Biogeochemistry and microbial diversity in the marine cavity beneath the McMurdo Ice Shelf, Antarctica:Biogeochemistry under the MCM ice shelf

Ice shelves surround ~ 75% of Antarctica's coastline and are highly sensitive to climate change; several have recently collapsed and others are predicted to in the near future. Marine waters beneath ice shelves harbor active ecosystems, while adjacent seas can be important areas of bottom water formation. Despite their oceanographic significance, logistical constraints have resulted in few opportunities to directly sample sub-ice shelf cavities. Here, we present the first data on microbial diversity and biogeochemistry beneath the McMurdo Ice Shelf (MIS) near Ross Island, Antarctica. Physicochemical profiles obtained via a 56 m deep borehole through the MIS revealed three vertically layered water masses (Antarctic Surface Water [AASW], Ice Shelf Water [ISW], and modified High Salinity Shelf Water [mHSSW]). Metabolically active, moderately diverse (Shannon diversity from 2.06 to 5.74) microbial communities were detected in the AASW and mHSSW. Heterotrophic bacterial production and dissolved organic matter concentrations were higher (12-37% and 24%, respectively) in mHSSW relative to AASW. Chemoautotrophic production was 5.3 nmol C L-1 d-1 and 6.0 nmol C L-1 d-1 in the AASW and mHSSW, respectively. Phytoplankton cells were more abundant and larger in the mHSSW sample relative to the AASW, which indicates sinking of phytoplankton produced in surface waters and, together with southerly flowing currents (0.09-0.16 m s-1), horizontal advection of phytoplankton from McMurdo Sound. Advected phytoplankton carbon together with in situ chemoautotrophic production provide important sources of organic matter and other reduced compounds to support ecosystem processes in the dark waters in the ice shelf cavity

Co-optimización del recurso agua y de los sistemas eléctricos: análisis en el contexto de la integración regional

Tesis para optar al grado de Magíster en Ciencias de la Ingeniería, Mención EléctricaMemoria para optar al título de Ingeniera Civil EléctricaProyecciones del Banco Mundial y la Agencia Internacional de Energía estiman un aumento de la población, de la demanda de energía y del consumo de agua hacia el año 2040. El impacto del cambio climático modificará la disponibilidad de recursos hídricos en América Latina. Esto último repercute directamente en la hidroelectricidad, que representó el 56% de la producción total de energía de América Latina en el año 2015, y en la agricultura, la cual es una actividad económica clave en la región y un usuario intensivo de la tierra, agua y energía. La relevancia del nexo Agua-Energía es ampliamente reconocida, pero de los modelos y análisis disponibles no existe ninguno que optimice la operación y planificación del nexo e incluya a su vez todas las dimensiones de esta interdependencia. Tampoco se han considerado sistemas transfronterizos, siendo lo más extenso territorialmente la aplicación a nivel país. Por medio de una adaptación de la función objetivo y restricciones, e incorporación de nuevas restricciones al modelo de optimización, se estima e integra el costo de riego no suministrado, a un modelo de coordinación hidrotérmica, dada la importancia del uso del agua en la agricultura. A partir de la validación del modelo para un caso base, se presenta el estudio de América Latina continental a través de un sistema interconectado regional. Se analizan 13 escenarios con el fin de capturar las dinámicas y acoplamientos entre los sistemas eléctricos de potencia y el uso del recurso agua en el año 2040. Los escenarios considerados reflejan los impactos proyectados del cambio climático según las trayectorias de concentración representativas, el uso de sistemas de almacenamiento, la gestión de la demanda eléctrica y un mayor desarrollo de energía solar. Los escenarios de planificación al año 2040 son construídos con el apoyo de una herramienta de planificación centralizada. Así, los resultados obtenidos muestran que la consideración de una matriz con mayor penetración solar aumenta el costo de operación total del sistema, lo que no implica una disminución del riego abastecido, en un contexto sin rivalidad entre hidroelectricidad y riego. Bajo un escenario de rivalidad entre ambos usos y alta penetración de energía solar, se disminuye drásticamente el abastecimiento de riego, producto del uso del agua embalsada como sistema de flexibilidad a bajo costo, para gestionar la variabilidad del recurso solar. El modelo de co-optimización propuesto y el análisis del caso de estudio, proporcionan una herramienta de apoyo al momento de querer conocer el efecto que tendrían las decisiones tomadas hacia el año 2040 por los diferentes actores del sistema, tanto en el sistema eléctrico como en los recursos hídricos. Todo esto, bajo el supuesto de una operación centralizada e integrada a nivel continental, y en un contexto donde se afirma que operar y planificar de manera independiente no es coherente en el futuro que se proyecta. Se propone como trabajo futuro estudiar nuevos escenarios, complejizar el modelo en otros aspectos como restricciones de pre-despacho y/o alteración hidrológica, expandir esta herramienta a la planificación y que se implemente este modelo con diferentes combinaciones de ubicación de bocatomas de riego, dada la importancia que tiene en el cumplimiento de los requerimientos de riego.CONICYT N°2217080

Heredar mi encierro

Tesis para optar al título de periodistaEl proyecto consiste en la realización de un material audiovisual de carácter documental que logre relatar, mediante testimonios centrales y conductores, la situación de mujeres que se encuentran embarazadas o viviendo con hijos lactantes dentro de la cárcel. Se abordará la cotidianeidad de las mujeres y sus hijos, así como también se planteará una opción para revertir esta medida, la cual propone el proyecto de Ley Sayén. Duración: 21 minutos

Sporotrichosis Outbreak Due to Sporothrix brasiliensis in Domestic Cats at Magallanes, Chile: A One-Health-Approach Study

Sporotrichosis is an implantation mycosis with subcutaneo-lymphatic or, more rarely, a viscerally disseminated affection; it can be acquired through traumatic percutaneous inoculation of the fungus present in soil or plant matter, or by feline scratching. Among the causative agents, Sporothrix brasiliensis is considered the most virulent species with a high prevalence in Brazil and recently in Argentina. Objective: Describe a S. brasiliensis outbreak in domestic and feral cats detected in the Magallanes region of southern Chile. Materials and Methods: Between the months of July and September 2022, three cats presented with suppurative subcutaneous lesions located mainly on the head and thoracic limbs. The cytology revealed the presence of yeasts with morphological characteristics suggestive of Sporothrix spp. The histopathology confirmed pyogranulomatous subcutaneous lesions associated with the presence of the same yeasts. The fungal culture followed by the partial gene sequence and analysis of the ITS region confirmed the diagnosis of the S. brasiliensis as the causative agent. The cats were treated with itraconazole associated in one case with potassium iodide. The evolution of the patients was favorable in all cases. Conclusions: An outbreak caused by S. brasiliensis was detected in domestic and feral felines in austral Chile. The correct identification of this fungus and antifungigram is essential for treatment decisions and for designing dissemination control and prevention programs under a one health approach that consider the health of people, animals, and the environment

Assessment of Changes in the Oral Microbiome That Occur in Dogs with Periodontal Disease

The oral microbiome in dogs is a complex community. Under some circumstances, it contributes to periodontal disease, a prevalent inflammatory disease characterized by a complex interaction between oral microbes and the immune system. Porphyromonas and Tannerella spp. are usually dominant in this disease. How the oral microbiome community is altered in periodontal disease, especially sub-dominant microbial populations is unclear. Moreover, how microbiome functions are altered in this disease has not been studied. In this study, we compared the composition and the predicted functions of the microbiome of the cavity of healthy dogs to those with from periodontal disease. The microbiome of both groups clustered separately, indicating important differences. Periodontal disease resulted in a significant increase in Bacteroidetes and reductions in Actinobacteria and Proteobacteria. Porphyromonas abundance increased 2.7 times in periodontal disease, accompanied by increases in Bacteroides and Fusobacterium. It was predicted that aerobic respiratory processes are decreased in periodontal disease. Enrichment in fermentative processes and anaerobic glycolysis were suggestive of an anaerobic environment, also characterized by higher lipopolysaccharide biosynthesis. This study contributes to a better understanding of how periodontal disease modifies the oral microbiome and makes a prediction of the metabolic pathways that contribute to the inflammatory process observed in periodontal disease

Ocular Microbiome in a Group of Clinically Healthy Horses

The ocular microbiome in horses is poorly described compared to other species, and most of the information available in the literature is based on traditional techniques, which has limited the depth of the knowledge on the subject. The objective of this study was to characterize and predict the metabolic pathways of the ocular microbiome of a group of healthy horses. Conjunctival swabs were obtained from both eyes of 14 horses, and DNA extraction was performed from the swabs, followed by next generation sequencing and bioinformatics analyses employing DADA2 and PICRUSt2. A total of 17 phyla were identified, of which Pseudomonadota (Proteobacteria) was the most abundant (59.88%), followed by Actinomycetota (Actinobacteria) (22.44%) and Bacteroidota (Bacteroidetes) (16.39%), totaling an average of 98.72% of the communities. Similarly, of the 278 genera identified, Massilia, Pedobacter, Pseudomonas, Sphingomonas, Suttonella and Verticia were present in more than 5% of the samples analyzed. Both Actinobacteria and Bacteroides showed great heterogeneity within the samples. The most abundant inferred metabolic functions were related to vital functions for bacteria such as aerobic respiration, amino acid, and lipid biosynthesis