Understanding the effect of oxide components on proton mobility in phosphate glasses using a statical analysis approach.

The models to describe the proton mobility ( ) together with the glass transition temperature ( ) of proton conducting phosphate glasses employing the glass composition as descriptors have been developed using a statical analysis approach. According to the models, the effects of additional HO, MgO, BaO, LaO, WO, NbO, BO and GeO as alternative to PO were found as following. at is determined first by concentrations of HO and PO, and at increases with increasing HO concentration and decreasing PO.

Proton transport properties of proton-conducting phosphate glasses at their glass transition temperatures.

The proton transport properties of 32 kinds of proton-conducting phosphate glasses with broad ranges of glass transition temperature, proton conductivity, and the proton carrier concentration were studied. Almost constant proton mobility of around 2 × 10 cm V s at the glass transition temperature, corresponding to a diffusion coefficient of approximately 4 × 10 cm s, was found for the glasses. The reason why the diffusion coefficient of protons is almost constant in various proton-conducting phosphate glasses was discussed based on the role of the protons as a cross-linker within the phosphate framework via hydrogen bonding.

Chromosome 4q25 Variant rs6817105 Bring Sinus Node Dysfunction and Left Atrial Enlargement.

Genome-wide association studies have reported a strong association of the single nucleotide polymorphism (SNP) rs6817105 (T > C) on chromosome 4q25 with atrial fibrillation (AF), but phenotype alterations conferred by this SNP have not been described. We genotyped SNP rs6817105 and examined the relationships among rs6817105 genotype, clinical characteristics, echocardiographic parameters, and electrophysiological parameters in 574 AF patients and 1,554 non-AF controls. Further, multiple microRNAs (miRNAs) are reported to be involved in atrial remodeling and AF pathogenesis, so we investigated relationships between rs6817105 genotype and serum concentrations of 2555 miRNAs.

Maintenance of low inflammation level by the ZFHX3 SNP rs2106261 minor allele contributes to reduced atrial fibrillation recurrence after pulmonary vein isolation.

Introduction: The single nucleotide polymorphism (SNP) rs2106261 in the transcription factor gene ZFHX3 (16q22), a major regulator of inflammation, has been reported linking to atrial fibrillation (AF) by genome-wide association studies. Inflammation is known to be a strong predictor of atrial fibrillation recurrence after ablation, so we examined the association of the ZFHX3 SNP rs2106261 to inflammation marker expression and recurrence after AF ablation.

Methods: We genotyped ZFHX3 SNP rs2106261 and compared the minor (T) allele frequency between 362 paroxysmal AF (PAF) patients underwent pulmonary vein isolation (PVI) and 627 non-AF controls.

The mobility of proton carriers in phosphate glasses depends on polymerization of the phosphate framework.

Proton conducting phosphate glasses were prepared by electrochemical substitution of sodium ions with protons applied to glasses with the compositions xNaO-1WO-8NbO-5LaO-(86 - x)PO (x = 28, 32, 35, 38, and 40). The mobilities of proton carriers in the glasses were studied in terms of the polymerization degree of the phosphate framework. The proton mobility at 200 °C increased as the depolymerization of the phosphate framework developed up to x = 38, and decreased at x = 40.

Formation of Amorphous HZrSiPO by Electrochemical Substitution of Sodium Ions in NaZrSiPO with Protons.

The sodium ions in NaZrSiPO (NASICON) were substituted with protons using an electrochemical alkali-proton substitution (APS) technique at 400 °C under a 5% H/95% N atmosphere. The sodium ions in NASICON were successfully substituted with protons to a depth of <400 μm from the anode. Completely protonated NASICON, i.

Radiofrequency catheter ablation is effective for atrial fibrillation patients with hypertrophic cardiomyopathy by decreasing left atrial pressure.

Background: Radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) refractory to medical therapy remains controversial in patients with hypertrophic cardiomyopathy (HCM); the acute effects on the direct left atrial (LA) pressure are not completely understood.

Methods: We consecutively studied patients with HCM (=15) and without HCM (NHCM, =106) who underwent extensive encircling pulmonary vein isolation for drug-refractory AF. We compared clinical parameters, echocardiographic parameters, electrophysiological parameters, LA pressures using hemodynamic catheterization and recurrence rate in both groups.

Dexmedetomidine Depresses Sinoatrial and Atrioventricular Nodal Function Without Any Change in Atrial Fibrillation Inducibility.

It has been reported that dexmedetomidine (dex) has an impact on the cardiac conduction system and even has potential antiarrhythmic actions. We examined the influence of dex on the cardiac electrophysiological properties and atrial fibrillation (AF) inducibility. Adult paroxysmal AF patients were randomly assigned to receive (N = 107) or not receive (N = 108) dex during cardiac electrophysiological studies.

Electrical Remodeling of the Atrioventricular Node Caused by Persistent Atrial Fibrillation in Humans.

Background: An animal experiment showed that long-term atrial pacing or persistent atrial fibrillation (AF) caused electrical remodeling of the atrioventricular (AV) node. We aimed to test the hypothesis that persistent AF decreases the AV conductivity in human hearts.

Methods And Results: We retrospectively compared the cardiac electrophysiological properties between patients with paroxysmal AF who underwent catheter ablation (PXAF, N = 254) and those with persistent or longstanding persistent AF (PSAF, N = 213).

Increased left atrial pressure in non-heart failure patients with subclinical hypothyroidism and atrial fibrillation.

Background: The impact of subclinical hypothyroidism on the cardiovascular risk is still debated. We aimed to measure the relationship between subclinical hypothyroidism and the left atrial (LA) pressure.

Methods: The LA pressures and thyroid function were measured in consecutive patients undergoing atrial fibrillation (AF) ablation, who did not have any known heart failure, structural heart disease, or overt thyroid disease.

Common Variant Near HEY2 Has a Protective Effect on Ventricular Fibrillation Occurrence in Brugada Syndrome by Regulating the Repolarization Current.

Background: Risk stratification of Brugada syndrome (BrS) remains controversial and the majority of patients with BrS have no genetic explanation. We investigated relationships between genotypes of 3 single-nucleotide polymorphisms reported in a recent genome-wide association study and BrS phenotypes.

Methods And Results: SCN10A (rs10428132), SCN5A (rs11708996), and downstream from HEY2 (rs9388451) single-nucleotide polymorphisms were genotyped and compared between 95 Japanese patients with BrS and 1978 controls.

Phase separation and crystallization in sodium lanthanum phosphate glasses induced by electrochemical substitution of sodium ions with protons.

Electrochemical substitution of sodium ions with protons (alkali-proton substitution; APS), and the injection of proton carriers was applied to sodium lanthanum phosphate glasses. A clear and homogeneous material was obtained for a glass of composition 25NaO1/2-8LaO3/2-66PO5/2-1GeO2 following APS, with a resulting proton conductivity of 4 × 10(-6) S cm(-1) at 250 °C. The glass underwent phase separation and crystallization at temperatures >255 °C, forming a highly hygroscopic and proton conducting H3PO4 phase in addition to LaP5O14 and other unidentified phases.

Structural change of NaO1/2-WO3-NbO5/2-LaO3/2-PO5/2 glass induced by electrochemical substitution of sodium ions with protons.

Structural changes of 35NaO1/2-1WO3-8NbO5/2-5LaO3/2-51PO5/2 glass (1W-glass) before and after the electrochemical substitution of sodium ions with protons by alkali-proton substitution (APS) are studied by Raman and (31)P magic-angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopies. The glass before APS consists of (PO3(-))8.6(P2O7(4-)) chains on average and the terminal Q(1) units (-O-PO3(3-)) are bound to MO6 octahedra (M denotes niobium or tungsten) through P-O-M bonds.

Mechanical and substrate abnormalities of the left atrium assessed by 3-dimensional speckle-tracking echocardiography and electroanatomic mapping system in patients with paroxysmal atrial fibrillation.

Background: Left atrial (LA) remodeling progresses to electrical remodeling, contractile remodeling, and subsequently structural remodeling. Little is known about the relationship between LA electrical and anatomical remodeling and LA mechanical function.

Objectives: We aimed to clarify the relationship between LA mechanical function using 3-dimensional speckle-tracking echocardiography (3D-STE) and LA electrical remodeling using an electroanatomic mapping system (CARTO 3) and to estimate atrial fibrillation (AF) substrate in patients with paroxysmal AF (PAF).

Incomplete cure of tachycardia-induced cardiomyopathy secondary to rapid atrial fibrillation by heart rate control without sinus conversion.

Background: It is uncertain whether rate or rhythm control is more favorable for patients experiencing tachycardia-induced cardiomyopathy (TIC) secondary to rapid atrial fibrillation (AF).

Methods And Results: We compared the electrophysiological and hemodynamic properties and outcome after AF ablation in 20 patients with a history of decompensated TIC who maintained sinus rhythm or had paroxysmal AF (group 1), 32 with a history of decompensated TIC who had persistent or longstanding persistent AF (group 2), 377 without TIC who had paroxysmal AF (group 3), and 225 without TIC who had persistent or longstanding persistent AF (group 4). The corrected sinus node recovery time was more prolonged in group 2 than in groups 1, 3, or 4 (1,066 ± 946 vs.

Time-domain T-wave alternans is strongly associated with a history of ventricular fibrillation in patients with Brugada syndrome.

Aims: T-wave alternans (TWA) is an indicator of vulnerability to ventricular arrhythmias and is useful for predicting sudden cardiac death (SCD) in patients with various structural heart diseases. We evaluated whether high levels of time-domain TWA on ambulatory ECG (AECG) are associated with a history of ventricular fibrillation (VF) in Brugada syndrome (BrS) patients.

Methods And Results: We examined the associations among VF history, family history of SCD, spontaneous type 1 electrocardiogram (ECG), late potentials, VF induction by programmed electrical stimulation, and TWA in 45 BrS patients (44 males; mean age, 45 ± 15 years).

Spontaneous disappearance of coronary pseudoaneurysm due to coronary artery perforation following percutaneous coronary intervention.

In recent years, while therapeutic outcome after percutaneous coronary intervention is improving due to the introduction of drug-eluting stent and device development, procedure-related complications including coronary perforation may ineluctably occur though at low-frequency, even if careful manipulations are performed under IVUS guidance. Meanwhile, coronary pseudoaneurysm subsequent to coronary perforation is one of the complications at chronic phase infrequently experienced following percutaneous coronary intervention. To date, the incidence and natural history of pseudoaneurysm following coronary artery perforation remain unclear.

A case of idiopathic ventricular fibrillation in which implanted loop recorder was useful in application decision for implantation of implantable cardioverter-defibrillator.

Establishing a symptom-rhythm correlation in patients with unexplained syncope is complicated because of its sporadic, infrequent, and unpredictable nature. Recently, an implantable loop recorder (ILR) has become available to evaluate undiagnosed recurrent arrhythmic episodes particularly in unexplained syncopes, and its usefulness has been reported in patients with recurrent syncopes that remain unexplained after conventional work-up. A 65-year-old man was referred to our hospital for loss of consciousness with nocturnal paroxysmal seizures.

Cavity volume of ruptured plaque is an independent predictor for angiographic no-reflow phenomenon during primary angioplasty in patients with ST-segment elevation myocardial infarction.

Background: Plaque rupture plays a critical role for the development of acute myocardial infarction. However, whether quantitative parameters with regard to the cavity size of ruptured plaque are associated with no-reflow (NR) phenomenon following primary angioplasty remains to be elucidated.

Methods And Results: A total of 53 patients with de novo ST-elevation myocardial infarction (STEMI) who had plaque rupture at the culprit lesion defined by pre-intervention virtual histology intravascular ultrasound (VH-IVUS) were enrolled.

Ultra-slim laminated capillary array for high-speed DNA separation.

We developed a new kind of capillary array for electrophoresis by using the numerical-control (NC) wiring technique conventionally used to produce printed-circuit boards. Laminating two polyimide sheets after laying cylindrical capillaries between them according to designed geometries, we fabricated a 16-lane laminated capillary array (LCA) 9.9 cm long, 7.