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Introducción: La anemia es frecuente en pacientes con enfermedad renal crónica (ERC) y está relacionada con mayor mortalidad y menor calidad de vida. La introducción de la eritropoyetina recombinante representó un avance en el manejo de la anemia; no obstante, se evidenció un aumento en la tasa de enfermedades cardiovasculares y accidentes cerebrovasculares. Usualmente, la anemia se corrige parcialmente, encontrándose casos de hiporrespuesta al tratamiento. Métodos: Estudio observacional, analítico de casos y controles multicéntrico. Resultados: De 784 pacientes incluidos, 123 presentaron hiporrespuesta (15.69%). Los factores de riesgo identificados fueron: el sexo femenino (OR=2.188), la edad menor a 50 años (OR=3.846), índice de masa corporal menor a 23 kg/m² (OR=1.598), uso de bloqueadores del sistema renina angiotensina (OR=1.915), albúmina menor a 4.0 (OR=5.286), ferritina mayor o igual a 800 ng/ml (OR=4.775), saturación de transferrina menor de 20% (OR=5.803) y parathormona mayor o igual 500 μg/ml (OR=2.183). En el modelo multivariado, estas variables fueron significativas (P 0.05). Conclusión: El sexo femenino, la edad menor a 50 años, un índice de masa corporal menor a 23 kg/m², el uso de BRA, la albúmina baja, ferritina elevada, saturación de transferrina baja y parathormona elevada son factores de riesgo asociados a hiporrespuesta a eritropoyetina.

Soil ecosystems are important reservoirs of biodiversity, as they are the most diverse habitat on Earth. Microbial biodiversity plays key roles in many ecosystem services, including the support to biogeochemical cycles. However, despite great advances in the understanding of the role of soil microbiota in providing benefits to nature and humankind, there is still much knowledge to be gained from understudied areas across the globe. Indeed, underrepresentation of the Global South in ecological studies has been suggested as an important gap that could compromise global solutions to conservation and the current biodiversity and climate crisis. In the Southern hemisphere, the southwest of South America, which includes Chile, runs behind the rest of the continent on studies related to soil microbial diversity and ecosystem functions. Therefore, to gain a better understanding of the global biodiversity and environment crisis, essential perspectives and knowledge from underrepresented regions need to be acknowledged to avoid biases in the scientific community. The main objective of this work is to understand how soil microbial diversity has been studied in Chile and the Antarctic Peninsula since 1975 to identify main knowledge gaps and funding opportunities for future research. Our survey consists of 343 articles representing 1,335 sampling points from Continental Chile to the Antarctic Peninsula. It revealed a better representation of articles studying bacterial and fungal diversity in the extreme regions of Chile funded by both international funds and the National Agency for Research and Development (ANID). To study microbial diversity, cultivation-based methods are still the most commonly used, whereas molecular studies are increasing but insufficiently applied. We have identified and argued the need to enhance collaborative multi- and interdisciplinary efforts, fundings for sequencing effort, and long-term studies to provide robust and informative knowledge about soil microbial communities.

ObjectiveLow HDL-C (high-density lipoprotein cholesterol) is the most frequent dyslipidemia in Mexicans, but few studies have examined the underlying genetic basis. Our purpose was to identify genetic variants associated with HDL-C levels and cardiovascular risk in the Mexican population.Approach and resultsA genome-wide association studies for HDL-C levels in 2335 Mexicans, identified four loci associated with genome-wide significance: CETP, ABCA1, LIPC, and SIDT2. The SIDT2 missense Val636Ile variant was associated with HDL-C levels and was replicated in 3 independent cohorts (P=5.9×10−18 in the conjoint analysis). The SIDT2/Val636Ile variant is more frequent in Native American and derived populations than in other ethnic groups. This variant was also associated with increased ApoA1 and glycerophospholipid serum levels, decreased LDL-C (low-density lipoprotein cholesterol) and ApoB levels, and a lower risk of premature CAD. Because SIDT2 was previously identified as a protein involved in sterol transport, we tested whether the SIDT2/Ile636 protein affected this function using an in vitro site-directed mutagenesis approach. The SIDT2/Ile636 protein showed increased uptake of the cholesterol analog dehydroergosterol, suggesting this variant affects function. Finally, liver transcriptome data from humans and the Hybrid Mouse Diversity Panel are consistent with the involvement of SIDT2 in lipid and lipoprotein metabolism.ConclusionsThis is the first genome-wide association study for HDL-C levels seeking associations with coronary artery disease in the Mexican population. Our findings provide new insight into the genetic architecture of HDL-C and highlight SIDT2 as a new player in cholesterol and lipoprotein metabolism in humans.

In this first-person account, we describe the changes we made to align our graduate student-level community psychology class with a healing justice model. We undertook this intervention because the class started in March, at the beginning of the COVID-19 pandemic stay-at-home directive in our region. We describe the facets of a healing justice model, which promotes radical healing and collective action in a trauma-informed environment. We then discuss the changes we made to the class to better align with healing justice, including how enrolled students (i.e., co-authors) experienced the process of the course (e.g., reworking the syllabus, starting class with check-ins and an exercise to engage our parasympathetic nervous systems), as well as the content of the course (e.g., service projects to support people who are undocumented, unhoused, or minoritized in other ways; photovoice). We end with implications for teaching community psychology, including the importance of universal design, and for scholar-activist PhD programs.

AimsTrimethylamine N-oxide (TMAO), choline and betaine serum levels have been associated with metabolic diseases including type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD). These associations could be mediated by insulin resistance. However, the relationships among these metabolites, insulin resistance and NAFLD have not been thoroughly investigated. Moreover, it has recently been suggested that TMAO could play a role in NAFLD by altering bile acid metabolism. We examined the association between circulating TMAO, choline and betaine levels and NAFLD in obese subjects.MethodsSerum TMAO, choline, betaine and bile acid levels were measured in 357 Mexican obese patients with different grades of NAFLD as determined by liver histology. Associations of NAFLD with TMAO, choline and betaine levels were tested. Moreover, association of TMAO levels with non-alcoholic steatohepatitis (NASH) was tested separately in patients with and without T2D.ResultsTMAO and choline levels were significantly associated with NAFLD histologic features and NASH risk. While increased serum TMAO levels were significantly associated with NASH in patients with T2D, in non-T2D subjects this association lost significance after adjusting for sex, BMI and HOMA2-IR. Moreover, circulating secondary bile acids were associated both with increased TMAO levels and NASH.ConclusionsIn obese patients, circulating TMAO levels were associated with NASH mainly in the presence of T2D. Functional studies are required to evaluate the role of insulin resistance and T2D in this association, both highly prevalent in NASH patients.

Parque Nacional La Campana (PNLC) is recognized worldwide for its flora and fauna, rather than for its microbial richness. Our goal was to characterize the structure and composition of microbial communities (bacteria, archaea and fungi) and their relationship with the plant communities typical of PNLC, such as sclerophyllous forest, xerophytic shrubland, hygrophilous forest and dry sclerophyllous forest, distributed along topoclimatic variables, namely, exposure, elevation and slope. The plant ecosystems, the physical and chemical properties of organic matter and the soil microbial composition were characterized by massive sequencing (iTag-16S rRNA, V4 and ITS1-5F) from the DNA extracted from the soil surface (5 cm, n = 16). A contribution of environmental variables, particularly related to each location, is observed. Proteobacteria (35.43%), Actinobacteria (32.86%), Acidobacteria (10.07%), Ascomycota (76.11%) and Basidiomycota (15.62%) were the dominant phyla. The beta diversity (~80% in its axes) indicates that bacteria and archaea are linked to their plant categories, where the xerophytic shrub stands out with the most particular microbial community. More specifically, Crenarchaeote, Humicola and Mortierella were dominant in the sclerophyllous forest; Chloroflexi, Cyanobacteria and Alternaria in the xerophytic shrubland; Solicoccozyma in the dry sclerophyllous forest; and Cladophialophora in the hygrophilous forest. In conclusion, the structure and composition of the microbial consortia is characteristic of PNLC’s vegetation, related to its topoclimatic variables, which suggests a strong association within the soil microbiome.

Grid-connected power inverters are indispensable in modern electrical systems, playing a pivotal role in enhancing the integration of renewable energies into power grids. Their significance, primarily when functioning as grid-forming inverters, extends to maintaining the grid’s inertia and strength—a distinct advancement over traditional grid-following operations. As grid-forming inverters, these devices emulate the characteristics of synchronous generators and can act as robust voltage sources, providing essential ancillary services. This behavior is particularly relevant when integrating energy storage systems on the converters’ direct current side. Among the various inverter topologies, the current source inverter (CSI) has emerged as a promising yet underexplored alternative for grid-forming applications. CSIs, when paired with their AC output filters, can effectively operate as voltage sources, utilizing control strategies that facilitate the integration of renewable energies into the electrical system. Their design inherently manages output current fluctuations, reducing the need for restrictive current limitations or additional protective measures. This paper examines the operational region of CSIs, obtained through detailed modeling, to explore their advantages, challenges, and potential for enhancing grid-connected systems. Analyzing the operating region from the converter model verifies the limits of where the converter can operate in a plane of active and reactive powers. For a small prototype model operating with 7 amperes in DC and 120 V in AC, it is possible to supply or absorb active power exceeding 1000 W and manage maximum reactive power values around 500 VAr, as determined by its operating region. Simulations also confirm that small changes in the control reference, as little as 5%, towards the region’s right limits cause significant oscillations in the dynamic control responses. This research aims to deepen our understanding of CSIs’ operational capabilities and highlight their unique benefits in advancing grid-connected systems and promoting the integration of renewable energy using this technology.

El artículo que se presenta intenta responder a una de las consignas de este dosier, que trata sobre la circulación material o simbólica de bienes a través del Atlántico desde el siglo XVII hasta mediados del siglo XIX. Se focaliza la atención en el período inmediatamente posterior a la Revolución de mayo de 1810 hasta la caída del gobernador Juan Manuel de Rosas en 1852. Durante el mismo, se llevó a cabo una intensa circulación comercial que implicó la salida de libros desde diferentes puertos del mundo atlántico y la comercialización del objeto libro en Buenos Aires mediante diversos mecanismos. Se describen los mismos considerando que contribuyeron a la formación y consolidación de un mercado del libro muchas veces determinado por cuestiones completamente ajenas a la misma dinámica comercial. Nuestra fuente principal, además de la numerosa bibliografía existente, son los avisos comerciales publicados en La Gaceta Mercantil, estudiados de manera sistemática.

En memoria

Resumen Los cambios políticos sucedidos en Bolivia en los últimos 50 años llevaron a modificaciones en la participación de grupos subalternizados y en la apreciación ética de la vida. Este estudio pretende establecer las conductas bioéticas de la cosmovisión andina en aculturados, endoculturados y transculturizados en La Paz, Bolivia. Se trata de una investigación mixta, exploratoria, etnográfica, transversal, comparativa sincrónica, diacrónica y sistemática, en la cual se aplicó un cuestionario validado por expertos (alfa de Cronbach de 0,932) a 399 personas (5,3% aculturadas; 73,9%, endoculturadas y 20,8%, transculturalizadas). Los resultados contrastados por hermenéutica obtuvieron cinco categorías, de las cuales la categoría relacionalidad era independiente a la culturación (p=0,262); mientras que las categorías conciencia ecológica, complementariedad, reciprocidad, concepto de salud, modelo social y comunitario dependían entre sí (p=0,000). Se constató que los sujetos aculturados del área rural presentaban mayor conocimiento de la ética ancestral. Se recomienda la promoción de políticas educativas relacionadas a ética.

El objetivo del presente artículo es abordar la historia de los primeros años de funcionamiento del Hospital del Señor del Milagro de la ciudad de Salta (1848-1864) a fin de analizar las características que por entonces revistió esta institución, los agentes que en ella intervinieron y sus prácticas y representaciones relacionadas al cuidado de los enfermos. El estudio de estas variables nos permitirá aproximarnos a algunas de las particularidades del proceso de secularización en el espacio salteño y a las relaciones que se entablaron entre el poder civil y el eclesiástico en la configuración de una institución de ayuda social a mediados del siglo XIX. Sostenemos que los principios y los agentes religiosos desempeñaron un papel clave en la conformación del Estado provincial salteño y de que supieron articularse con los incipientes proyectos de modernización que se ciñeron sobre algunas instituciones decimonónicas.

Recent evidence shows that obesity correlates negatively with bone mass. However, traditional anthropometric measures such as body mass index could not discriminate visceral adipose tissue from subcutaneous adipose tissue. The visceral adiposity index (VAI) is a reliable sex-specified indicator of visceral adipose distribution and function. Thus, we aimed to identify metabolomic profiles associated with VAI and low bone mineral density (BMD). A total of 602 individuals from the Health Workers Cohort Study were included. Forty serum metabolites were measured using the targeted metabolomics approach, and multivariate regression models were used to test associations of metabolomic profiles with anthropometric, clinical, and biochemical parameters. The analysis showed a serum amino acid signature composed of glycine, leucine, arginine, valine, and acylcarnitines associated with high VAI and low BMD. In addition, we found a sex-dependent VAI in pathways related to primary bile acid biosynthesis, branched-chain amino acids, and the biosynthesis of pantothenate and coenzyme A (CoA). In conclusion, a metabolic profile differs by VAI and BMD status, and these changes are gender-dependent.

Background & aimsThe etiology of nonalcoholic fatty liver disease (NAFLD) is poorly understood, with males and certain populations exhibiting markedly increased susceptibility. Using a systems genetics approach involving multi-omic analysis of ∼100 diverse inbred strains of mice, we recently identified several candidate genes driving NAFLD. We investigated the role of one of these, liver pyruvate kinase (L-PK or Pklr), in NAFLD by using patient samples and mouse models.MethodsWe examined L-PK expression in mice of both sexes and in a cohort of bariatric surgery patients. We used liver-specific loss- and gain-of-function strategies in independent animal models of diet-induced steatosis and fibrosis. After treatment, we measured several metabolic phenotypes including obesity, insulin resistance, dyslipidemia, liver steatosis, and fibrosis. Liver tissues were used for gene expression and immunoblotting, and liver mitochondria bioenergetics was characterized.ResultsIn both mice and humans, L-PK expression is up-regulated in males via testosterone and is strongly associated with NAFLD severity. In a steatosis model, L-PK silencing in male mice improved glucose tolerance, insulin sensitivity, and lactate/pyruvate tolerance compared with controls. Furthermore, these animals had reduced plasma cholesterol levels and intrahepatic triglyceride accumulation. Conversely, L-PK overexpression in male mice resulted in augmented disease phenotypes. In contrast, female mice overexpressing L-PK were unaffected. Mechanistically, L-PK altered mitochondrial pyruvate flux and its incorporation into citrate, and this, in turn, increased liver triglycerides via up-regulated de novo lipogenesis and increased PNPLA3 levels accompanied by mitochondrial dysfunction. Also, L-PK increased plasma cholesterol levels via increased PCSK9 levels. On the other hand, L-PK silencing reduced de novo lipogenesis and PNPLA3 and PCSK9 levels and improved mitochondrial function. Finally, in fibrosis model, we demonstrate that L-PK silencing in male mice reduced both liver steatosis and fibrosis, accompanied by reduced de novo lipogenesis and improved mitochondrial function.ConclusionsL-PK acts in a male-specific manner in the development of liver steatosis and fibrosis. Because NAFLD/nonalcoholic steatohepatitis exhibit sexual dimorphism, our results have important implications for the development of personalized therapeutics.

Background & aimsThe etiology of nonalcoholic fatty liver disease (NAFLD) is poorly understood, with males and certain populations exhibiting markedly increased susceptibility. Using a systems genetics approach involving multi-omic analysis of ∼100 diverse inbred strains of mice, we recently identified several candidate genes driving NAFLD. We investigated the role of one of these, liver pyruvate kinase (L-PK or Pklr), in NAFLD by using patient samples and mouse models.MethodsWe examined L-PK expression in mice of both sexes and in a cohort of bariatric surgery patients. We used liver-specific loss- and gain-of-function strategies in independent animal models of diet-induced steatosis and fibrosis. After treatment, we measured several metabolic phenotypes including obesity, insulin resistance, dyslipidemia, liver steatosis, and fibrosis. Liver tissues were used for gene expression and immunoblotting, and liver mitochondria bioenergetics was characterized.ResultsIn both mice and humans, L-PK expression is up-regulated in males via testosterone and is strongly associated with NAFLD severity. In a steatosis model, L-PK silencing in male mice improved glucose tolerance, insulin sensitivity, and lactate/pyruvate tolerance compared with controls. Furthermore, these animals had reduced plasma cholesterol levels and intrahepatic triglyceride accumulation. Conversely, L-PK overexpression in male mice resulted in augmented disease phenotypes. In contrast, female mice overexpressing L-PK were unaffected. Mechanistically, L-PK altered mitochondrial pyruvate flux and its incorporation into citrate, and this, in turn, increased liver triglycerides via up-regulated de novo lipogenesis and increased PNPLA3 levels accompanied by mitochondrial dysfunction. Also, L-PK increased plasma cholesterol levels via increased PCSK9 levels. On the other hand, L-PK silencing reduced de novo lipogenesis and PNPLA3 and PCSK9 levels and improved mitochondrial function. Finally, in fibrosis model, we demonstrate that L-PK silencing in male mice reduced both liver steatosis and fibrosis, accompanied by reduced de novo lipogenesis and improved mitochondrial function.ConclusionsL-PK acts in a male-specific manner in the development of liver steatosis and fibrosis. Because NAFLD/nonalcoholic steatohepatitis exhibit sexual dimorphism, our results have important implications for the development of personalized therapeutics.

La enseñanza de las matemáticas en las escuelas de lenguaje en Chile ha sido escasamente investigada. Una de los factores que lo explican tiene relación con que no existe co-docencia con profesores de matemáticas. Por tanto, la educación especial se ha focalizado en el desarrollo del lenguaje y la educación matemática lo ha ignorado. En este contexto, esta investigación caracteriza la enseñanza de las nociones lógico-matemáticas en clases impartidas por educadoras especiales en una escuela de lenguaje. Desde un enfoque cualitativo, el diseño de esta investigación contempla la grabación de aula de dos docentes especiales y sus respectivos cursos. Mediante un análisis de contenido, los resultados obtenidos revelan mayoritariamente que las docentes focalizan sus clases en aspectos simbólicos del desarrollo de las nociones lógico-matemáticas. Concluimos que esto responde a la falta de orientaciones ministeriales claras y a la escasa formación docente en la educación especial en el área de las matemáticas

Objetivo. Determinar los factores higiénico-sanitarios asociados a la contaminación microbiológica de la carne de pollo comercializada en los mercados municipales de El Salvador. Materiales y métodos. Se realizó un estudio transversal analítico en los 33 mercados municipales de las cabeceras departamentales de El Salvador. La muestra se calculó a partir de 456 puestos de venta, obteniendo un total de 256 puestos. Por cada puesto se obtuvo una muestra de carne de pollo. El análisis microbiológico se realizó en el Laboratorio Nacional de Salud Pública. Se calcularon frecuencias, porcentajes, medidas de tendencia central y de asociación utilizando SPSS versión 21. Resultados. En el 74% de las muestras se encontró Escherichia coli, en el 24%, Staphylococcus aureus y en el 16%, Salmonela spp. La presencia de Salmonella spp, estuvo asociada con el no uso de desinfectante para las manos y no utilizar toalla para secarse las manos. La presencia de E. coli estuvo asociada al uso de accesorios personales y la inadecuada temperatura de almacenamiento. Mientras que la presencia de S. aureus, estuvo asociada a la falta de lavado de manos, no utilizar toalla para secarse las manos y no utilizar delantal. Conclusión. Las condiciones higiénico-sanitarias de los manipuladores y de los puestos de venta están asociadas a la contaminación microbiológica en la carne de pollo comercializada en El Salvador.

ABSTRACT Small colony variants are relatively common among some bacterial species and are associated with poor prognosis and recalcitrant infections. Similarly, Candida glabrata—a major intracellular fungal pathogen—produces small and slow-growing respiratory-deficient colonies, termed “petite.” Despite reports of clinical petite C. glabrata strains, our understanding of petite behavior in the host remains obscure. Moreover, controversies exist regarding in-host petite fitness and its clinical relevance. Herein, we employed whole-genome sequencing (WGS), dual-RNAseq, and extensive ex vivo and in vivo studies to fill this knowledge gap. WGS identified multiple petite-specific mutations in nuclear and mitochondrially encoded genes. Consistent with dual-RNAseq data, petite C. glabrata cells did not replicate inside host macrophages and were outcompeted by their non-petite parents in macrophages and in gut colonization and systemic infection mouse models. The intracellular petites showed hallmarks of drug tolerance and were relatively insensitive to the fungicidal activity of echinocandin drugs. Petite-infected macrophages exhibited a pro-inflammatory and type I IFN-skewed transcriptional program. Interrogation of international C. glabrata blood isolates (n = 1000) showed that petite prevalence varies by country, albeit at an overall low prevalence (0%–3.5%). Collectively, our study sheds new light on the genetic basis, drug susceptibility, clinical prevalence, and host-pathogen responses of a clinically overlooked phenotype in a major fungal pathogen. Importance Candida glabrata is a major fungal pathogen, which is able to lose mitochondria and form small and slow-growing colonies, called “petite.” This attenuated growth rate has created controversies and questioned the clinical importance of petiteness. Herein, we have employed multiple omics technologies and in vivo mouse models to critically assess the clinical importance of petite phenotype. Our WGS identifies multiple genes potentially underpinning petite phenotype. Interestingly, petite C. glabrata cells engulfed by macrophages are dormant and, therefore, are not killed by the frontline antifungal drugs. Interestingly, macrophages infected with petite cells mount distinct transcriptomic responses. Consistent with our ex vivo observations, mitochondrial-proficient parental strains outcompete petites during systemic and gut colonization. Retrospective examination of C. glabrata isolates identified petite prevalence a rare entity, which can significantly vary from country to country. Collectively, our study overcomes the existing controversies and provides novel insights regarding the clinical relevance of petite C. glabrata isolates.