Differential cardiomyocyte transcriptomic remodeling during in vitro Trypanosoma cruzi infection using laboratory strains provides implications on pathogenic host responses.

BACKGROUND: Chagas disease can lead to life-threatening cardiac manifestations. Regional factors, including genetic characteristics of circulating Trypanosoma cruzi (T. cruzi), have attracted attention as likely determinants of Chagas disease phenotypic expression and Chagas cardiomyopathy (CCM) progression. Our objective was to elucidate the differential transcriptomic signatures of cardiomyocytes resulting from infection with genetically discrete T. cruzi strains and explore their relationships with CCM pathogenesis and progression. METHODS: HL-1 rodent cardiomyocytes were infected with T. cruzi trypomastigotes of the Colombian, Y, or Tulahuen strain. RNA was serially isolated post-infection for microarray analysis. Enrichment analyses of differentially expressed genes (fold-change ≥ 2 or ≤ 0.5) highlighted over-represented biological pathways. Intracellular levels of reactive oxygen species (ROS) were compared between T. cruzi-infected and non-infected HL-1 cardiomyocytes. RESULTS: We found that oxidative stress-related gene ontology terms (GO terms), 'Hypertrophy model', 'Apoptosis', and 'MAPK signaling' pathways (all with P < 0.01) were upregulated. 'Glutathione and one-carbon metabolism' pathway, and 'Cellular nitrogen compound metabolic process' GO term (all with P < 0.001) were upregulated exclusively in the cardiomyocytes infected with the Colombian/Y strains. Mean intracellular levels of ROS were significantly higher in the T. cruzi-infected cardiomyocytes compared to the non-infected (P < 0.0001). CONCLUSIONS: The upregulation of oxidative stress-related and hypertrophic pathways constitutes the universal hallmarks of the cardiomyocyte response elicited by T. cruzi infection. Nitrogen metabolism upregulation and glutathione metabolism imbalance may implicate a relationship between nitrosative stress and poor oxygen radicals scavenging in the unique pathophysiology of Chagas cardiomyopathy.

Contenido de fluoruro en dentífricos de venta en el mercado nacional / Fluoride content in toothpastes sold in the national market

Introducción: Actualmente, existe una gran variedad de pastas dentales que se pueden encontrar en el mercado nacional, para diferentes propósitos. Entre éstas se hallan las empleadas para la prevención de caries. Éstas contienen fluoruro en diversas concentraciones como agente terapéutico, y casi en su totalidad estipulan en sus marbetes un contenido de 1,000 a 1,450 partes por millón (ppm) de fluoruro. Algunos estudios han mostrado que las concentraciones de fluoruro especificadas en la etiqueta y lo encontrado en el dentífrico no coinciden. Objetivo: Evaluar la concentración de fluoruro total con base en la Norma Mexicana NMX-K-539-CNCP-2013, que establece que los dentífricos no deben contener más de 1,500 ppm de fluoruro. Así como determinar si lo declarado en el marbete de sus empaques corresponde al contenido real de fluoruro. Material y métodos: El estudio se realizó, por triplicado, en 37 pastas dentífricas. El método para determinar la concentración de fluoruro fue el de ion selectivo, descrito por la Farmacopea de los Estados Unidos Mexicanos. Resultados: El promedio de concentración de este elemento fue de 1,262 ppm F- (± 170.7). El 59% de los dentífricos analizados no contienen la cantidad estipulada en el marbete. Conclusiones: Las concentraciones de fluoruro de los dentífricos se encuentran dentro de la Norma. Las concentraciones no corresponden a lo estipulado en el empaque (AU)

Introduction: Currently, there is a wide variety of toothpastes, which can be found in the national market, for different purposes. Among these are those used for the prevention of dental caries. These, contain fluoride in various concentrations as a therapeutic agent, and almost in their entirety, stipulate in their labels a content of 1,000 to 1,450 ppm of fluoride. Some studies have shown that the fluoride concentrations specified on the label, and what is found in the toothpaste do not match. Objective: To evaluate the concentration of total fluoride based on the Mexican Standard NMX-K-539-CNCP-2013, which establishes that toothpastes should not contain more than 1,500 ppm of fluoride. As well as determining if what is stated on the label of their packaging corresponds to the actual content of fluoride. Material and methods: The study was carried out, in triplicate, on 37 toothpastes. The method for determining the fluoride concentration was that of selective ion, described by the Pharmacopoeia of the United Mexican States. Results: The average concentration of this element was 1,262 ppm F- (± 170.7). Fifty nine percent of the dentifrices analyzed do not contain the amount stipulated in the label. Conclusions: The fluoride concentrations of dentifrices are within the Standard. The concentrations do not correspond to what is stipulated in the package (AU)