Browsing by Author "Rojas, Marcelo"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Publication
    Characterization of microbial communities from gut microbiota of hypercholesterolemic and control subjects
    (2022) Morales, Cristian; Rojas, Gabriel; Rebolledo, Camilo; Rojas, Marcelo; Arias, Raúl; Cuadros, Sara; Maracaja, Vinicius; Saavedra, Kathleen; Leal, Pamela; Lanas, Fernando; Salazar, Luis; Saavedra, Nicolas
    Introduction: In recent years, several studies have evidenced the importance of the microbiome to host physiology as metabolism regulator, along with its potential role in triggering various diseases. In this study, we analyzed the gut microbiota in hypercholesterolemic (cases) and normocholesterolemic (controls) individuals to identify characteristic microbial signature for each condition. Methods: Stool samples were obtained from 57 adult volunteers (27 hypercholesterolemic and 30 controls). The taxonomic profiling of microbial communities was performed using high-throughput sequencing of 16S rRNA V3-V4 amplicons, followed by data analysis using Quantitative Insights Into Microbial Ecology 2 (QIIME2) and linear discriminant analysis (LDA) effect size (LEfSe). Results: Significant differences were observed in weight, height, body mass index (BMI) and serum levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol (LDL-C) between the groups (p<0.05). LEfSe showed differentially abundant prokaryotic taxa (α=0.05, LDA score > 2.0) in the group of hypercholesterolemic individuals (Methanosphaera, Rothia, Chromatiales, Clostridiales, Bacillaceae and Coriobacteriaceae) and controls (Faecalibacterium, Victivallis and Selenomonas) at various taxonomic levels. In addition, through the application of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUSt2), the predominance of pathways related to biosynthesis in hypercholesterolemic patients was established, compared to controls in which degradation pathways were predominant. Finally, in the analysis of co-occurrence networks, it was possible to identify associations between the microorganisms present in both studied groups. Conclusion: Our results point out to unique microbial signatures, which likely play a role on the cholesterol metabolism in the studied population.
  • Thumbnail Image
    Item
    Exome Sequencing Identifies Genetic Variants Associated with Extreme Manifestations of the Cardiovascular Phenotype in Marfan Syndrome
    (2022) Jimenez, Yanireth; Paulsen, Cesar; Turner, Eduardo; Iturra, Sebastian; Cuevas, Oscar; Lay-Son, Guillermo; Repetto, Gabriela; Rojas, Marcelo; Calderon, Juan
    Marfan Syndrome (MFS) is an autosomal dominant condition caused by variants in the fibrillin-1 (FBN1) gene. Cardinal features of MFS include ectopia lentis (EL), musculoskeletal features and aortic root aneurysm and dissection. Although dissection of the ascending aorta is the main cause of mortality in MFS, the clinical course differs considerably in age of onset and severity, even among individuals who share the same causative variant, suggesting the existence of additional genetic variants that modify the severity of the cardiovascular phenotype in MFS. We recruited MFS patients and classified them into severe (n = 8) or mild aortic phenotype (n = 14) according to age of presentation of the first aorta-related incident. We used Exome Sequencing to identify the genetic variants associated with the severity of aortic manifestations and we performed linkage analysis where suitable. We found five genes associated with severe aortic phenotype and three genes that could be protective for this phenotype in MFS. These genes regulate components of the extracellular matrix, TGFβ pathway and other signaling pathways that are involved in the maintenance of the ECM or angiogenesis. Further studies will be required to understand the functional effect of these variants and explore novel, personalized risk management and, potentially, therapies for these patients.
  • Thumbnail Image
    Item
    Reticencia vacunal ante el SARS-COV2 y redes sociales
    (2022) Soto, Macarena; Rojas, Marcelo; Valdés, Danitza; Valdebenito, Sebastián
    Introducción: Las vacunas son consideradas el “salvavidas” para acabar con la actual pandemia del Covid 19, sin embargo, existe un grupo de personas que incurren en la denominada reticencia vacunal, fenómeno que puede verse influenciado por muchos factores y uno de ellos es la variedad de información fraudulenta, desinformación y poco interés de informarse de fuentes confiables. Objetivo: Conocer la influencia de las redes sociales en la toma de decisión ante el proceso de vacunación por el virus SARS-COV-2. Metodología: Se hizo un análisis bibliográfico en Scholar Google, UptoDate, Pubmed y Scielo, con la palabra clave “vaccination refusal”. Resultado: El rechazo a la vacunación es la causa de varios procesos de tomas de decisiones, los cuales están influenciados por determinantes como la falsa creencia acerca de que la vacuna puede provocar la infección activa de COVID, razones de índole religioso, ideológico o de conciencia basados en las consecuencias de la vacunación, y el riesgo que conlleva el procedimiento. Conclusión: La reticencia vacunal es un problema complejo. Las medidas para afrontar esta problemática deben incluir un aumento de los recursos con que cuentan los profesionales para aclarar dudas y promover la vacunación entre sus usuarios, pero, además, es necesario trabajar en estrategias que mejoren la comprensión de la importancia de la vacunación en la población general yla mejora de la confianza en las instituciones responsables de las estrategias de vacunación, tanto a nivel local como global.

Implementado por OpenGeek Services