Necrotizing sarcoid granulomatosis in a family of patients with sarcoidosis reinforces the association between both entities

Necrotizing sarcoid granulomatosis (NSG) is a rare entity mainly characterized by a prominent granulomatous vasculitis affecting middle-aged or old individuals and with a favorable prognosis. Although many believe it is a variant of sarcoidosis, the proper classification is still a matter of debate as some of its features are found in sarcoidosis but also in Churg-Strauss syndrome, Wegener's disease and hypersensitivity pneumonitis. In this paper, we described for the first time a case of NSG in a family with several cases of sarcoidosis, reinforcing the relationship between NSG and sarcoidosis. Additional interesting findings were the young age of the patient (15 years old), the symptoms limited to the respiratory tract (uncommon when NSG affects youngsters) and the increase in serologic markers of autoimmune disease. Though complete criteria for autoimmune disease were not present, systemic lupus erythematosus and Sjogren's syndrome are possible candidates. As sarcoidosis is described to be associated with several autoimmune diseases, this finding is an additional suggestion of the relationship between both entities.     

Circadian dynamics of heart rate and physical activity in patients with heart failure

The present study was designed to develop a method to continuously measure Holter electrocardiogram (ECG) and physical activity in terms of metabolic costs to examine circadian dynamics of RR intervals and physical activity in patients with heart failure. A total of 7 healthy subjects and 3 heart failure patients performed cardiopulmonary exercise test using four-stage graded treadmill walking at 0% grade to examine whether the acceleration signals in the vertical direction could reflect actual body energy expenditure during physical activity. Then, using this new method, 24-hr monitorings of ECG and physical activity were performed in 24 inpatients with heart failure while they were allowed to walk around freely. Our results showed the integral of rectified acceleration signals was closely correlated with actual metabolic cost in all subjects. Instantaneous changes in heart rate were quite concordant with physical activity. As compared with the asymptomatic patients (n = 12), the symptomatic patients (n = 12) had lower energy expenditure during 8-hr daytime periods but higher mean heart rate. Furthermore, a more prominent ultradian rhythm of circadian changes in heart rate and physical activity was found in 50% of all subjects studied. The simultaneous analysis of Holter ECG and physical activity as the same time series revealed that in patients with heart failure, sympathovagal balance shifted toward sympathotonic conditions and their physical activity could become subject to intrinsic ultradian dynamics of body's homeostasis.     

Interaction between ACE and ADD1 gene polymorphisms in the progression of IgA nephropathy in Japanese patients

An interaction effect between the angiotensin-converting enzyme insertion/deletion (ACE I/D) and alpha-adducin (ADD1) Gly460Trp polymorphisms (G460W) on blood pressure regulation has recently been suggested, although its significance in the prognosis of renal function in IgA nephropathy (IgAN) has not been fully investigated. Therefore, we evaluated the clinical manifestations and renal prognosis in 276 Japanese patients with histologically proven IgAN with respect to their ACE I/D and ADD1 G460W polymorphisms. The prognosis of renal function was analyzed by Kaplan-Meier survival curves and multivariate Cox proportional-hazards regression models. Baseline data, including blood pressures, proteinuria, renal function, and incidence of hypertension, were similar for the different genotypes of ACE and ADD1. The individual genotypes taken alone were not associated with the progression of renal dysfunction. However, renal survival of patients with the 460WW polymorphism of ADD1 was significantly worse within the group with the II genotype of ACE (Kaplan-Meier, log rank test; chi2=6.062, P=0.0138) but not for those with other ACE genotypes. In the Cox proportional-hazards regression model with adjustment for clinical risk factors, including hypertension, proteinuria, and no administration of an angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, the 460WW variant of ADD1 was a highly significant and independent risk factor only for patients with the ACE II genotype, with a hazard ratio of 3.65 (P=0.0016), but not for those with other ACE genotypes (hazard ratio=0.65, P=0.2902). These findings suggest an interaction between ACE and ADD1 polymorphisms not only on blood pressure regulation but also on the progression of renal dysfunction in patients with IgAN.     

Effect of verapamil on regional coronary and myocardial perfusion during acute coronary occlusion

To elucidate the mechanism of action of the calcium antagonist verapamil, S-T segment mapping, retrograde coronary flow and regional coronary resistance were studied in 28 dogs subjected to acute coronary occlusion. Retrograde coronary flow was measured directly through catheterization of the distal occluded coronary artery. Regional coronary resistance was calculated by dividing mean distal coronary pressure by coronary flow. Verapamil (0.8 mg/kg) administered intravenously to eight dogs 30 minutes before coronary occlusion significantly reduced S-T segment elevation as compared with occlusion alone (p < 0.025); heart rate and diastolic pressure were also reduced (p < 0.05) but systolic pressure remained essentially unchanged. When verapamil was given to seven dogs within 30 minutes after coronary occlusion, there was a significant increase in retrograde coronary flow (p < 0.05) and a decrease in regional coronary resistance (p < 0.05). Simultaneously, heart rate and heart rate-blood pressure product declined significantly (p < 0.05), suggesting a reduction in myocardial oxygen consumption. Systolic blood pressure was unaltered, and diastolic pressure decreased only transiently. In 13 control dogs there was no significant change in any of these variables during the observation period. Thus, verapamil during acute coronary occlusion protects the ischemic myocardium by both increasing perfusion and reducing myocardial oxygen consumption.     

Inhibitory effect of ceramide on insulin-induced protein kinase Czeta translocation in rat adipocytes

Ceramide has been confirmed to be a signal mediator of apoptosis that is induced by tumor necrosis factor-alpha (TNF-alpha). It has also been reported that ceramide may induce insulin resistance as well as TNF-alpha. We investigated the effect of ceramide on insulin signaling pathways, such as insulin receptor (IR) beta-subunit, insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and protein kinase Czeta (PKCzeta) in rat adipocytes. We examined insulin-stimulated [(3)H]2-deoxyglucose (2-DOG) uptake in rat adipocytes pretreated with N-hexanoylsphingosine (C(6)-ceramide, 10 to 30 micromol/L). Insulin-induced 2-DOG uptake was significantly reduced by C(6)-ceramide pretreatment. We also examined the effect of various concentrations of C(6)-ceramide pretreatment on insulin-induced autophosphorylation of the IR beta-subunit, tyrosine phosphorylation of IRS-1, enzyme activity of PI3K, and membrane-associated PKCzeta immunoreactivity. Pretreatment with C(6)-ceramide significantly reduced autophosphorylation of the IR beta-subunit, tyrosine phosphorylation of IRS-1, and enzyme activity of PI3K. Moreover, membrane-associated PKCzeta immunoreactivity and immunoprecipitable PKCzeta enzyme activity, downstream of PI3K, were significantly suppressed by C(6)-ceramide pretreatment. These results suggest that ceramide may induce insulin resistance via the suppression of IRS-1-PI3K signaling, and subsequent activation of PKCzeta.     

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.