Analysis of Polymorphisms in the MATN3 and DOT1L Genes and CTX-II Urinary Levels in Patients with Knee Osteoarthritis in a Northeast Mexican-Mestizo Population.

Aims: To investigate the possible roles of the single nucleotide polymorphisms (SNPs) MATN3 (rs77245812) and DOT1L (rs12982744) with susceptibility to knee osteoarthritis (KOA) among mestizos from the northeast region of Mexico. In addition, we analyzed the relationship of their urinary levels of carboxy terminal telopeptide of collagen type II (CTX-II) and the radiological grade of disease. Materials and Methods: A total of 223 individuals from a Northeast Mexico Mestizo population were included in this study: 110 patients with primary KOA and 113 healthy controls. Genotyping of the MATN3 (rs77245812) and DOT1L (rs12982744) SNPs was performed by real-time polymerase chain reaction. Results: No association was found between the polymorphisms MATN3 (rs77245812), DOT1L (rs12982744), and the risk of developing KOA (odds ratio [OR] = 1.33, 95% confidence interval [CI] = 0.42-6.48, p = 0.621) (OR = 2.03, 95% CI = 0.35-11.5, p = 0.422). However, urinary CTX-II levels were considerably higher by radiographic grade. Conclusions: An increase in CTX-II per radiographic grade was observed in the case group, but no association was found between MATN3 and DOT1L genes and the risk of KOA in Mexican mestizos.

Calcium-calmodulin-dependent protein kinase mediates the intracellular signalling pathways of cardiac apoptosis in mice with impaired glucose tolerance.

KEY POINTS: Spontaneous sarcoplasmic reticulum (SR) Ca2+ release events increased in fructose-rich diet mouse (FRD) myocytes vs. control diet (CD) mice, in the absence of significant changes in SR Ca2+ load. In HEK293 cells, hyperglycaemia significantly enhanced [3 H]ryanodine binding and Ca2+ /calmodulin-dependent protein kinase II (CaMKII) phosphorylation of RyR2-S2814 residue vs. normoglycaemia. These increases were prevented by CaMKII inhibition. FRD significantly augmented cardiac apoptosis in WT vs. CD-WT mice, which was prevented by co-treatment with the reactive oxygen species scavenger Tempol. Oxidative stress was also increased in FRD-SR-autocamide inhibitory peptide (AIP) mice, expressing the SR-targeted CaMKII inhibitor AIP, without any significant enhancement of apoptosis vs. CD-SR-AIP mice. FRD produced mitochondrial swelling and membrane depolarization in FRD-WT mice but not in FRD-S2814A mice, in which the CaMKII site on ryanodine receptor 2 was ablated. FRD decreased mitochondrial area, mean Feret diameter and the mean distance between SR and the outer mitochondrial membrane vs. CD hearts. This remodelling was prevented in AC3I mice, with cardiac-targeted CaMKII inhibition. ABSTRACT: The impact of cardiac apoptosis in pre-diabetic stages of diabetic cardiomyopathy is unknown. We show that myocytes from fructose-rich diet (FRD) animals exhibit arrhythmias produced by exacerbated Ca2+ /calmodulin-protein kinase (CaMKII) activity, ryanodine receptor 2 (RyR2) phosphorylation and sarcoplasmic reticulum (SR) Ca2+ leak. We tested the hypothesis that this mechanism also underlies cardiac apoptosis in pre-diabetes. We generated a pre-diabetic model in FRD mice. FRD mice showed an increase in oxidative stress, hypertrophy and systolic dysfunction. FRD myocytes exhibited enhanced SR Ca2+ spontaneous events in the absence of SR Ca2+ load alterations vs. control-diet (CD) myocytes. In HEK293 cells, hyperglycaemia significantly enhanced [3 H]ryanodine binding and CaMKII phosphorylation of RyR2-S2814 residue vs. normoglycaemia. CaMKII inhibition prevented hyperglycaemia-induced alterations. FRD also evoked cardiac apoptosis in WT mice vs. CD-WT mice. Co-treatment with the reactive oxygen species scavenger Tempol prevented FRD-induced apoptosis in WT mice. In contrast, FRD enhanced oxidative stress but not apoptosis in FRD-SR-AIP mice, in which a CaMKII inhibitor is targeted to the SR. FRD produced mitochondrial membrane depolarization in WT mice but not in S2814A mice, in which the CaMKII phosphorylation site on RyR2 was ablated. Furthermore, FRD decreased mitochondrial area, mean Feret diameter and mean SR-mitochondrial distance vs. CD-WT hearts. This remodelling was prevented in AC3I mice, with cardiac-targeted CaMKII inhibition. CaMKII phosphorylation of RyR2, SR Ca2+ leak and mitochondrial membrane depolarization are critically involved in the apoptotic pathway of the pre-diabetic heart. The FRD-induced decrease in SR-mitochondrial distance is likely to additionally favour Ca2+ transit between the two organelles.

Efecto bactericida de la cal hidratada en solución acuosa / Bactericidal effect of hydrated lime in aqueous solution

Se determinó el efecto bactericida de los sebrenadantes de las soluciones saturadas de cal común y de hidróxido de calcio (Ca(OH)2) micronizado (1500 mg/L), que se usó a manera de testigo, comparándolo con el de los desinfectantes constituídos por soluciones de plata coloidal al 0,33 por ciento (0,0016mg/L), sulfacloramina de tolueno (41 mg/L) con bicarbonato de sodio (9 mg/L) e hipoclorito de sodio (5 mg/L). Para ello se emplearon cuatro cepas de Vibrio cholerae No. 01, V. parahaemolyticus, Escherichia coli, salmonella typhimurium, shigella flexneri, Sh. sonnei y Sa. enteritidis. Estas bacterias se usaron para inocular las sustancias bactericidas ya citadas y, después de distintos tiempos de incubación, las bacterias sobrevivientes se cuantificaron in vitro por medio de la técnica de vaciado en placa. El resultado se expresó en unidades formadoras de colonias (UFC). Se estimó in situ la carga de V. cholerae soltada por 35 fresas y 35 rábanos (con un peso aproximado de 10 g por unidad) al lavarlos bajo un chorro de agua potable, sumergirlos en el sobrenadantes de una solución saturada de cal (1,5 g/L), y ambas cosas. El mayor efecto bactericida se obtuvo con V. cholerae O1 y se observó a los 3 minutos. Otras enterobacterias resistieron el efecto bactericida hasta 30 minutos (AU)