Differential effects of beta-adrenergic agonists and antagonists in LQT1, LQT2 and LQT3 models of the long QT syndrome

AbstractOBJECTIVESTo define the cellular mechanisms responsible for the development of life-threatening arrhythmias in response to sympathetic activity in the congenital and acquired long QT syndromes (LQTS).METHODSTransmembrane action potentials (AP) from epicardial (EPI), M and endocardial (ENDO) cells and a transmural electrocardiogram were simultaneously recorded from an arterially perfused wedge of canine left ventricle. We examined the effect of beta-adrenergic agonists and antagonists on action potential duration (APD90), transmural dispersion of repolarization (TDR) and the development of Torsade de Pointes (TdP) in models of LQT1, LQT2 and LQT3 forms of LQTS.RESULTSIKsblock with chromanol 293B (LQT1) homogeneously prolonged APD90of the three cell types without increasing TDR. Addition of isoproterenol prolonged QT and APD90of M but abbreviated that of EPI and ENDO, causing a persistent increase in TDR; Torsade de Pointes developed or could be induced only in the presence of isoproterenol. IKrblock with d-sotalol (LQT2) and augmentation of late INawith ATX-II (LQT3) prolonged APD90of M more than EPI and ENDO, causing increases in QT and TDR. TdP developed in the absence of isoproterenol. In LQT2 isoproterenol initially prolonged, then abbreviated, the APD90of M but always abbreviated EPI, thus transiently increasing TDR and the incidence of TdP. In LQT3, isoproterenol always abbreviated APD90of the three cell types, causing a persistent decrease in TDR and suppression of TdP. The arrhythmogenic as well as protective actions of isoproterenol were reversed by propranolol.CONCLUSIONSOur data suggest that beta-adrenergic stimulation induces TdP by increasing transmural dispersion of repolarization in LQT1 and LQT2 but suppresses TdP by decreasing dispersion in LQT3. The data indicate that beta-blockers are protective in LQT1 and LQT2 but may facilitate TdP in LQT3

Development of a 4.2 V aqueous hybrid electrochemical capacitor based on MnO2 positive and protected Li negative electrodes

An aqueous hybrid electrochemical capacitor consisting of a capacitive manganese oxide (MnO2) positive electrode and a water-stable, protected Li negative electrode in near-neutral aqueous electrolyte (1.0 M Li2SO4, pH = 5.5) is demonstrated. Galvanostatic charge/discharge cycling tests were conducted with pouched cells, offering a cell voltage of 4.2 V with maximum specific energy of 753 W h kg(-1) based on the positive electrode. The combination of a pseudocapacitive MnO2 positive and a Li negative electrode offers high specific charge and cell voltage, resulting in an aqueous hybrid electrochemical capacitor having exceptionally high specific energy.ArticleJOURNAL OF POWER SOURCES. 241:572-577 (2013)journal articl

2005年～2012年の広島における blaIMP-1インテグロンを含むIS26複合トランスポゾン保有緑膿菌（ST235クローン）の持続的流行伝播

広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

Development of Supreme Super High-Density Realtime Disaster Mitigation System for Gas Supply System

With the 3,700 New SI sensors installed throughout its service area (3,100 km2), Tokyo Gas has started to develop its super high-density real-time disaster mitigation system SUPREME for gas supply systems. Immediately after an earthquake, seismic data from the New SI sensors is relayed to the main system where extremely precise estimates of the damage are made on the spot. Damage estimation consists of making an estimate of the surface distribution of seismic motion that takes account of the site amplification factor, and making an estimate of damage to the pipeline network that takes account of factors such as the types of the pipes, the topography of the area, and the liquefaction conditions

4 V class aqueous hybrid electrochemical capacitor with battery-like capacity

A new aqueous hybrid electrochemical capacitor consisting of a porous positive capacitive electrode and a water-stable multilayered Li negative electrode is demonstrated. The new cell design affords cell voltages close to 4 V in a mild aqueous electrolyte. Application of a pseudocapacitive positive electrode with high specific charge results in specific energy comparable to present rechargeable batteries.ArticleRSC ADVANCES. 2(32):12144-12147 (2012)journal articl