Identification of quantitative trait loci for cardiac hypertrophy in two different strains of the spontaneously hypertensive rat.

Cardiac hypertrophy and left ventricular hypertrophy are known to be substantially controlled by genetic factors. As an experimental model, we undertook genome-wide screens for cardiac mass in F2 populations bred from the stroke-prone spontaneously hypertensive rats (SHRSP) and normal spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) of a Japanese colony. Two F2 cohorts were independently produced: F2(SHRSP x WKY) (110 male and 110 female rats) and F2(SHR x WKY) (151 male rats). The ratio of heart weight to body weight (Hw/Bw) was evaluated at 12 months of age in F2(SHRSP x WKY) after salt-loading for 7 months, and at around 15 weeks of age in F2(SHR x WKY) who had been fed a normal rat chow diet. Subsequent to an initial screen with 251 markers in F2(SHRSP x WKY) male progeny, 170 and 161 markers were selected and characterized in F2(SHRSP x WKY) female progeny and F2(SHR x WKY) male progeny, respectively. Markers from four chromosomal regions showed suggestive or significant linkage to Hw/Bw. The strongest and the most consistent linkage was found in the vicinity of D3Mgh16 on rat chromosome (RNO) 3 (a maximal log of the odds score reached 4.0 to 6.6 across the F2 populations studied). In the other three regions on RNO6, RNO10 and RNO13, the degree of linkage was more prominent in either males or females. These data provide solid evidence for a "principal" RNO3 quantitative trait loci regulating Hw/Bw in SHRSP and SHR, and also suggest the possible presence of sexual dimorphism in regard to genetic susceptibility for cardiac hypertrophy.     

Clinical significance of left atrial geometry in dilated cardiomyopathy patients: A cardiovascular magnetic resonance study

BackgroundClinical significance of left atrial (LA) function and geometry in patients with dilated cardiomyopathy (DCM) remains uncertain.HypothesisLA geometric parameters assessed by cardiac magnetic resonance (CMR) predict the prognosis in patients with DCM.MethodsThe present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA sphericity index was computed as the ratio of the measured maximum LA volume by the volume of a sphere with maximum LA length diameter.ResultsWe included 255 patients in this study. During the mean follow‐up of 3.92 years, hospitalization for HF occurred in 37 patients. The LA sphericity index was significantly higher in patients with hospitalization for HF than in those without (0.78 ± 0.35 vs. 0.58 ± 0.18, p < .001). Multivariable Cox regression analysis identified a higher LA sphericity index as an independent predictor of hospitalization for HF. Patients were categorized based on the median of LA sphericity index. The Kaplan–Meier curve showed that patients with a high LA sphericity index (≥0.57) had a significantly higher risk of hospitalization for HF than those with a low LA sphericity index (<0.57).ConclusionLA sphericity index was an independent predictor of hospitalization for HF. Assessment of LA geometric parameters might be useful for risk stratification in patients with DCM.     

Role of electrophysiologic study (EPS)-guided preventive therapy for the management of ventricular tachyarrhythmias in patients with heart failure.

BACKGROUND: Ventricular tachyarrhythmias (VT/VF) are 1 of the most important factors determining the prognosis of patients with heart failure (HF). Although priority is given to implantable cardioverter defibrillator (ICD) therapy for the prevention of sudden cardiac death, electrophysiologic-study (EPS)-guided preventive therapy could be important for reducing the number of cardiac events. METHODS AND RESULTS: Of 864 patients with a history of HF, an EPS was performed in 168 and 121 had inducible VT/VF. Under the basic therapy of an ICD, additional catheter ablation was attempted for 95 of 124 monomorphic VT foci in 74 patients, and 78 of the VT were successfully ablated. The prognoses were compared among 5 patient groups with different results for the EPS and catheter ablation: (1) success group (n=43), (2) failure group (n=15), (3) not attempted group (n=16), (4) VF group (n=47), and (5) no inducible VT/VF group. During a follow-up period of 31+/-22 months, the incidence of VT/VF was lower in the success and no inducible VT/VF groups than in the other groups (p=0.0018), although a significant difference was not observed for the total deaths. CONCLUSION: EPS-guided preventive therapy using an ICD and catheter ablation can be useful, at least for the reduction of arrhythmic events in patients with HF.     

An Irreversible Worsening Cardiac Function after Withdrawing Medical Treatments in a Patient with Dilated Cardiomyopathy: A Pathological Analysis

A 44-year-old man diagnosed with idiopathic dilated cardiomyopathy was admitted to our hospital with acute decompensated heart failure. Seven years before this admission, the first introduction of medication resulted in left ventricular (LV) recovery, which was sustained for several years. However, the patient stopped taking his medication, resulting in worsening of the LV function. Despite the second introduction of medication, the LV function did not improve. We performed cardiac magnetic resonance imaging and an endomyocardial biopsy, which revealed the significant development of cardiac fibrosis that had not been present at the time of the initial diagnosis.     

Allograft liver failure awaiting liver transplantation in Japan

Journal of Gastroenterology - Following liver transplantation (LT), allograft liver failure can be developed by various causes and requires re-LT. Hence, this study aimed to clarify the...     

Paroxysmal atrial fibrillation coincident with cardiac decompensation is a predictor of poor prognosis in chronic heart failure.

BACKGROUND: The prognostic significance of atrial fibrillation (AF) in chronic heart failure (CHF) remains poorly understood. METHODS AND RESULTS: Death and rehospitalizaion for CHF exacerbation for 427 consecutive patients hospitalized from 1996 to 2002 were retrospectively analyzed in relation to cardiac rhythm: sinus rhythm (SR; n=239) or AF (n=188). The AF group was classified according to an Intervention (n=57) or Non-Intervention (n=131) group for defibrillating AF. During the follow-up of 34+/-23 months, there was no significant difference of mortality or morbidity between the SR and AF groups, or between the Intervention and Non-Intervention groups, respectively. However, the Non-Intervention group consisted of 28 patients with paroxysmal AF (PAF), which spontaneously converted to SR during hospitalization, and 103 with chronic AF (CAF). The rehospitalization for CHF exacerbation was significantly higher in PAF than that in CAF and SR (p=0.00005 and 0.002, respectively). Multivariate Cox analysis demonstrated that, PAF, but not CAF, was a predictor of readmission (relative risk 2.30, p=0.004, 95% confidence interval 1.30 to 4.05). CONCLUSIONS: The present data implied that PAF coincident with cardiac decompensation could be a new predictor of prognosis for CHF. The management strategies of AF in CHF should be discussed according to the phenotype of AF.     

Effects of dextran sulfates on the acute infection and growth stages of Toxoplasma gondii

Toxoplasma gondii is one of the most prevalent parasites, causing toxoplasmosis in various warm-blooded animals, including humans. Because of the broad range of hosts susceptible to T. gondii, it had been postulated that a universal component of the host cell surface, such as glycosaminoglycans (GAGs), may act as a receptor for T. gondii infection. Carruthers et al. (Infect Immun 68:4005–4011, 2000) showed that soluble GAGs have also been shown to disrupt parasite binding to human fibroblasts. Therefore, we investigated the inhibitory effect of GAGs and their analogue dextran sulfate (DS) on T. gondii infection. For up to 24 h of incubation after inoculation of T. gondii, the inhibitory effect of GAGs on T. gondii infection and growth inside the host cell was weak. In contrast, DS markedly inhibited T. gondii infection. Moreover, low molecular weight DS particularly slowed the growth of T. gondii inside host cells. DS10 (dextran sulfate MW 10 kDa) was the most effective agent in these in vitro experiments and was therefore tested for its inhibitory effects in animal experiments; infection inhibition by DS10 was confirmed under these in vivo conditions. In this report, we showed that DSs, especially DS10, have the potential of a new type of drug for toxoplasmosis.     

Induction of secondary metabolite production by fungal co-culture of Talaromyces pinophilus and Paraphaeosphaeria sp.

Fungal co-culture is a strategy to induce the production of secondary metabolites by activating cryptic genes. We discovered the production of a new compound, talarodone A (1), along with five known compounds 2–6 in co-culture of Talaromyces pinophilus and Paraphaeosphaeria sp. isolated from soil collected in Miyazaki Prefecture, Japan. Among them, the productions of penicidones C (2) and D (3) were enhanced 27- and sixfold, respectively, by the co-culture. The structure of 3 should be represented as a γ-pyridol form with the reported chemical shifts, but not as a γ-pyridone form, based on DFT calculation.     

The relationship between age and minimum alveolar concentration of sevoflurane for maintaining bispectral index below 50 in children

We evaluated the minimum alveolar concentration of sevoflurane required to maintain the bispectral index below 50 in children. We studied 55 children, divided into 1‐year‐old, 2‐ to 4‐year‐old and 5‐ to 9‐year‐old groups and used Dixon's up‐and‐down method and probit analysis. In the 1‐year‐old group, the bispectral index values remained above 50, with the end‐tidal sevoflurane concentration reaching 4.0% or higher. The minimum alveolar concentration of sevoflurane for maintaining the bispectral index below 50 was significantly higher in the 2‐ to 4‐year‐old group (2.33%, 95% CI 2.25–2.57) than in the 5‐ to 9‐year‐old group (2.10%, 95% CI 1.94–2.25; p = 0.005). We conclude that assessing the depth of anaesthesia using bispectral index is unreliable in children aged < 2 years anaesthetised with sevoflurane.