Numerical verification of random phase-and-amplitude formalism of weak turbulence

The Random Phase and Amplitude Formalism (RPA) has significantly extended the scope of weak turbulence studies. Because RPA does not assume any proximity to the Gaussianity in the wavenumber space, it can predict, for example, how the fluctuation of the complex amplitude of each wave mode grows through nonlinear interactions with other modes, and how it approaches the Gaussianity. Thus, RPA has a great potential capability, but its validity has been assessed neither numerically nor experimentally. We compare the theoretical predictions given by RPA with the results of direct numerical simulation (DNS) for a three-wave Hamiltonian system, thereby assess the validity of RPA. The predictions of RPA agree quite well with the results of DNS in all the aspects of statistical characteristics of mode amplitudes studied here

Onset heart rate of microvolt-level T-wave alternans provides clinical and prognostic value in nonischemic dilated cardiomyopathy

AbstractObjectivesThis study was designed to determine the prognostic value of onset heart rate (OHR) in T-wave alternans (TWA) in patients with nonischemic dilated cardiomyopathy (DCM).BackgroundOne of the current major issues in DCM is to prevent sudden cardiac death (SCD). However, the value of the OHR of TWA as a prognostic indicator in DCM remains to be elucidated.MethodsWe prospectively investigated 104 patients with DCM undergoing TWA testing. The end point of this study was defined as SCD, documented sustained ventricular tachycardia/ventricular fibrillation. Relations between clinical parameters and subsequent outcome were evaluated.ResultsForty-six patients presenting with TWA were assigned to one of the following two subgroups according to OHR for TWA of ≤100 beats/min: group A (n = 24) with OHR ≤100 beats/min and group B (n = 22) with 100 < OHR ≤ 110 beats/min. T-wave alternans was negative in 37 patients (group C) and indeterminate in 21 patients. The follow-up result comprised 83 patients with determined TWA. During a follow-up duration of 21 ± 14 months, there was a total of 12 arrhythmic events, nine of which included three SCDs in group A, two in group B and one in group C. The forward stepwise multivariate Cox hazard analysis revealed that TWA with an OHR ≤100 beats/min and left ventricular ejection fraction were independent predictors of these arrhythmic events (p = 0.0001 and p = 0.0152, respectively).ConclusionsThe OHR of TWA is of additional prognostic value in DCM

Prevalence of gastroesophageal reflux disorder in arrhythmic patients and adjunctive effects of proton pump inhibitors on comorbid atrial fibrillation

Background: Although the coexistence of atrial fibrillation (AF) and gastroesophageal reflux disorder (GERD) has been reported, the prevalence of GERD in arrhythmic patients remains unknown. This study aimed to investigate the relationship between GERD and several kinds of arrhythmia, and the therapeutic effects of proton pump inhibitors (PPI) on AF.Methods: In Study 1, patients with various kinds of arrhythmia (n=147) including AF (n=98) were administered a GERD-specific questionnaire (F-scale). In Study 2, patients with AF and GERD (n=27) responded to an AF-specific questionnaire (AFQLQ) before and after the additive PPI therapy to explore the effects of PPI on comorbid AF. In Study 3, device memory was assessed as it is related to PPI administration in pacemaker patients with GERD and AF (n=5) to study the effects of PPI on device-documented AF.Results: Left atrial (LA) size and F-scale scores in AF patients were the largest among the arrhythmic patients in Study 1. Logistic regression analysis showed no independent determinants of GERD. F-scale scores and AFQLQ scores showed temporal and partial correlations and significant improvement after starting PPI in Study 2. However, device interrogation confirmed limited AF improvement by starting PPI in Study 3.Conclusions: GERD is prevalent in AF patients. LA size is not an independent determinant of GERD. Symptoms of AF were improved, whereas device-documented paroxysms of AF were not ameliorated by PPI administration. A large-scale prospective study is required to conclude the efficacy of PPI on the comorbid AF

Advances in apheresis therapy for glomerular diseases

This article is an overview of the immunomodulatory effects of apheresis in renal diseases, especially primary and secondary glomerulonephritis, and the clinical evidence for the efficacy of apheresis therapy. Permeability factor(s) derived from circulating T cells are speculated to have a crucial role in the proteinuria of nephrotic syndrome (NS). Plasma exchange (PE); immunoadsorption plasmapheresis (IAPP), using protein A sepharose cartridges; low-density lipoprotein apheresis; and lymphocytapheresis (LCAP) have been used to remove such factors or pathogenic T cells. Other glomerular diseases induced by specific antibodies such as anti-glomerular basement membrane antibodies, anti-neutrophil cytoplasmic antibodies, and immune-complexes have also been treated with PE, double-filtration plasmapheresis, IAPP, and LCAP. Recommendations, based on the evidence from recent randomized controlled studies, have been established in apheresis therapy for various glomerular diseases. © 2007 Japanese Society of Nephrology

Predictive importance of left ventricular myocardial stiffness for the prognosis of patients with congestive heart failure

SummaryObjectivesThis study was designed to determine the prognostic importance of left ventricular (LV) myocardial stiffness, a hemodynamic index which is closely related to B-type natriuretic peptide (BNP) concentration in patients with congestive heart failure (CHF).BackgroundWhile elevated BNP, an abnormality of cardiac neurohormones, is known to be an independent marker of death or re-admission, it remains to be clarified whether there is also a strong predictor directly related to cardiac dysfunction.MethodsLV performance variables and stress–strain analyses including diastolic myocardial stiffness constant (Km) were obtained from 37 patients with initial CHF by the combined simultaneous measurement of echocardiographic and hemodynamic data. Survivors were monitored for a mean of 23 months, with the main endpoint being combined death or first re-admission for CHF.ResultsTen patients (27%) were primary endpoint cases. Both Km and plasma BNP levels were higher in the event than in the event-free group. By Cox proportional hazards analysis, Km≥4.0 was identified as the only variable with significant and independently incremental predictive power to affect the primary endpoint (adjusted hazard ratio=7.354, 95% confidence interval 1.379–39.232, p=0.02).ConclusionsIn patients with CHF, increased myocardial stiffness may have greater prognostic significance compared to other conventional predictors. Increased myocardial stiffness may be considered to be an important prognostic factor independent of the loading conditions

Magma Plumbing System at Izu-Oshima Volcano, Japan: Constraints From Petrological and Geochemical Analyses

The Izu-Oshima volcano is one of the most active volcanoes in Japan, and has generated relatively large-scale eruptions every 30–40 years for the past 200 years. As more than 30 years have passed since the last eruptions in 1986–87, volcanic activity is expected to resume in the near future. To help elucidate the current and future state of the volcano’s magma system, the temporal evolution of the recent magma plumbing system was investigated through a petrological and geochemical analysis of its basaltic lavas and pyroclastics (&lt;∼53 wt.% of SiO2) that were erupted during the last ∼1.5 kyr. The basaltic products have variable phenocryst contents, ranging from ∼0 to ∼20 vol.%, and phenocryst-bearing samples commonly contain plagioclase, orthopyroxene, and clinopyroxene phenocrysts. The whole-rock compositions are significantly scattered in the Harker variation diagrams, suggesting that the compositional diversity was established by at least two independent magmatic processes. The application of principal component analysis on the whole-rock major element data suggests that one magmatic process was crystal fractionation of crystal-poor magmas, and the other process was either plagioclase accumulation or mixing of plagioclase-rich magmas. Based on this observation, and combined with the petrological analysis and previous geophysical studies, we propose that aphyric magmas, stored in an 8–10 km-deep magma chamber, progressively differentiated over time from the 7th to 20th century. Furthermore, the compositional variations in basalts resulted from the mixing of the differentiating aphyric magmas with variable proportions of porphyritic magmas derived from a 13–18 km-deep magma chamber. Because recent eruptions have been triggered by the ascent of porphyritic magma from the 13–18 km-deep magma chamber, and its injection into the 8–10 km-deep magma chamber, it is important to monitor the deeper magma chamber to predict future volcanic activity

Intra-cardiac echocardiography guided catheter ablation of a right posterior accessory pathway in a patient with Ebstein׳s anomaly

AbstractWe report a case of Ebstein׳s anomaly in which radiofrequency catheter ablation of an accessory pathway was successfully performed under intra-cardiac echocardiography. A 50-year-old woman was referred to our hospital for radiofrequency catheter ablation of a paroxysmal supraventricular tachycardia. A 12-lead surface electrocardiogram revealed ventricular pre-excitation associated with type B Wolff–Parkinson–White syndrome. In the baseline electrophysiological study, an orthodromic atrioventricular reciprocating tachycardia with a right posterior accessory pathway was induced. A phased-array intra-cardiac echo probe was positioned in the right atrium to visualize the atrioventricular junction. The key structures for catheter ablation, such as the atrialized right ventricle, atrioventricular junction, and tricuspid valve, were clearly visualized on intra-cardiac echocardiography. Radiofrequency current was successfully delivered at the atrioventricular junction, where a Kent potential was recorded. During a 6-month follow-up period, the patient was free from arrhythmias. The findings in this case suggest that phased-array intra-cardiac echocardiography is useful for ablation of right-sided accessory pathways in patients with Ebstein׳s anomaly

Effects of 6-month eicosapentaenoic acid treatment on postprandial hyperglycemia, hyperlipidemia, insulin secretion ability, and concomitant endothelial dysfunction among newly-diagnosed impaired glucose metabolism patients with coronary artery disease. An open label, single blinded, prospective randomized controlled trial

Additional file 2: Table S2. Comparison of cookie meal test data between baseline and 6 months, and comparison of absolute change from baseline among patients with baseline plasma glucose <110 mg/dL

Conditioned medium from stem cells derived from human exfoliated deciduous teeth ameliorates NASH via the Gut-Liver axis

Non-alcoholic steatohepatitis (NASH) occurrence has been increasing and is becoming a major cause of liver cirrhosis and liver cancer. However, effective treatments for NASH are still lacking. We examined the benefits of serum-free conditioned medium from stem cells derived from human exfoliated deciduous teeth (SHED-CM) on a murine non-alcoholic steatohepatitis (NASH) model induced by a combination of Western diet (WD) and repeated administration of low doses of carbon tetrachloride intraperitoneally, focusing on the gut-liver axis. We showed that repeated intravenous administration of SHED-CM significantly ameliorated histological liver fibrosis and inflammation in a murine NASH model. SHED-CM inhibited parenchymal cell apoptosis and reduced the activation of inflammatory macrophages. Gene expression of pro-inflammatory and pro-fibrotic mediators (such as Tnf-α, Tgf-β, and Ccl-2) in the liver was reduced in mice treated with SHED-CM. Furthermore, SHED-CM protected intestinal tight junctions and maintained intestinal barrier function, while suppressing gene expression of the receptor for endotoxin, Toll-like receptor 4, in the liver. SHED-CM promoted the recovery of Caco-2 monolayer dysfunction induced by IFN-γ and TNF-α in vitro. Our findings suggest that SHED-CM may inhibit NASH fibrosis via the gut-liver axis, in addition to its protective effect on hepatocytes and the induction of macrophages with unique anti-inflammatory phenotypes