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tion of GP and PVCs foci may be an effective, safe treatment in patients with concomitant VVS and idiopathic PVCs.Duchenne muscular dystrophy (DMD) is a genetic neuromuscular disease characterized by progressive muscle weakness and wasting. Stimulation of AMP-activated protein kinase (AMPK) has been demonstrated to increase muscle function and protect muscle against damage in dystrophic mice. Metformin is a widely used anti-hyperglycemic drug and has been shown to be an indirect activator of AMPK. Reverse Transcriptase inhibitor Based on these findings, we sought to determine the effects of metformin on neuromuscular deficits in mdx murine model of DMD. In this study, we found metformin treatment increased muscle strength accompanied by elevated twitch and tetanic force of tibialis anterior (TA) muscle in mdx mice. Immunofluorescence and electron microscopy analysis of metformin-treated mdx muscles revealed an improvement in muscle fiber membrane integrity. Electrophysiological studies showed the amplitude of miniature endplate potentials (mEPP) was increased in treated mice, indicating metformin also improved neuromuscular transmission of the mdx mice. Analysis of mRNA and protein levels from muscles of treated mice showed an upregulation of AMPK phosphorylation and dystrophin-glycoprotein complex protein expression. In conclusion, metformin can indeed improve muscle function and diminish neuromuscular deficits in mdx mice, suggesting its potential use as a therapeutic drug in DMD patients.

Pulmonary arterial (PA) stiffness has an essential contribution to the right ventricular (RV) failure pathogenesis. A comprehensive and multiparameter risk assessment allows predicting mortality and guiding treatment decisions in PA hypertension (PAH). We characterize PA remodeling with intravascular ultrasound (IVUS) in prevalent and stable patients with PAH according to the ESC/ERS risk table and analyze the RV-PA coupling consequences.

Ten control subjects and 20 prevalent PAH adult patients underwent right heart catheterization (RHC) with simultaneous IVUS study. We estimated cardiac index (CI), pulmonary vascular resistance, and compliance (PVR, PAC) by standard formulas. From IVUS and RHC data, PA diameter, wall thickness/luminal diameter ratio, and indexes of stiffness (pulsatility, compliance, distensibility, incremental elastic modulus – Einc-, and the stiffness index β) were measured. We evaluated RV-PA coupling by the ratio of tricuspid annular plane systolic excursion to systolic pulmonary artth PAC and RV-PA coupling impairment beyond the indirect effect of the mean PA pressure. The concomitant assessment of IVUS and hemodynamic parameters at diagnosis and follow-up of PAH patients could be a feasible and safe tool for risk stratification and treatment response of the PA vasculopathy during serial hemodynamic measurements.

In prevalent PAH patients, the severity of proximal PA remodeling is related to the risk stratification and associated with PAC and RV-PA coupling impairment beyond the indirect effect of the mean PA pressure. The concomitant assessment of IVUS and hemodynamic parameters at diagnosis and follow-up of PAH patients could be a feasible and safe tool for risk stratification and treatment response of the PA vasculopathy during serial hemodynamic measurements.Computational fluid dynamic-based modeling is commonly used in stenosed and stented coronary artery to characterize blood flow and identify hemodynamics factors that could lead to coronary stenosis. One such factor is the residence time (RT), which is important for investigating stenosis and restenosis progression. The current method to calculate RT, known as the relative residence time (RRT) method, does not provide the original scale of RT and only provides a relative value. We recently introduced a novel method, designated as RT method, based on developing the advection-diffusion equation with a scalar to calculate the absolute residence time. The goal of this study was to compare both methods. Our results show that both could detect regions with a high risk of stenosis and restenosis, but the RT method is also able to show the recirculation zone using pathlines in the lumen and quantify actual RT. Moreover, RT method also provided blood flow pathlines, and is correlated to wall shear stress (WSS), oscillatory shear index (OSI), RRT, and Localized Normalized Helicity (LNH) which are other critical factors to gauge stenosis severity and assess stenting in bifurcations coronary.Many reptiles are able to continuously replace their teeth through life, an ability attributed to the existence of epithelial stem cells. Tooth replacement occurs in a spatially and temporally regulated manner, suggesting the involvement of diffusible factors, potentially over long distances. Here, we locally disrupted tooth replacement in the leopard gecko (Eublepharis macularius) and followed the recovery of the dentition. We looked at the effects on local patterning and functionally tested whether putative epithelial stem cells can give rise to multiple cell types in the enamel organs of new teeth. Second generation teeth with enamel and dentine were removed from adult geckos. The dental lamina was either left intact or disrupted in order to interfere with local patterning cues. The dentition began to reform by 1 month and was nearly recovered by 2-3 months as shown in μCT scans and eruption of teeth labeled with fluorescent markers. Microscopic analysis showed that the dental lamina was fully healed by 1 month. The deepest parts of the dental lamina retained odontogenic identity as shown by PITX2 staining. A pulse-chase was carried out to label cells that were stimulated to enter the cell cycle and then would carry BrdU forward into subsequent tooth generations. Initially we labeled 70-78% of PCNA cells with BrdU. After a 1-month chase, the percentage of BrdU + PCNA labeled cells in the dental lamina had dropped to 10%, consistent with the dilution of the label. There was also a population of single, BrdU-labeled cells present up to 2 months post surgery. These BrdU-labeled cells were almost entirely located in the dental lamina and were the likely progenitor/stem cells because they had not entered the cell cycle. In contrast fragmented BrdU was seen in the PCNA-positive, proliferating enamel organs. Homeostasis and recovery of the gecko dentition was therefore mediated by a stable population of epithelial stem cells in the dental lamina.