Finite element stress analysis of indirect restorations prepared in cavity bases

The objective of this study was to analyze the distribution of tensile stresses in indirect restorations prepared in several composite cavity bases. Elastic moduli of 20 materials were measured by nanoindentation technique for finite element analysis. Axisymmetric models of posterior onlays were constructed using combinations of two onlay materials and three cavity base materials. Thickness of resin cement was 50 um. A vertical load of 95.5 N was applied on the cusp tip. Maximum stress of 18.1 MPa was found in the model consisting of a ceramic onlay and a flowable resin composite base. It was also found that tensile stress increased as the area of the base having a lower elastic modulus became wider. Base materials having higher elastic moduli were determined to be suitable as cavity base materials for posterior restorations.     

Role of diacylglycerol kinase in cellular regulatory processes: a new regulator for cardiomyocyte hypertrophy

Diacylglycerol (DAG) kinase (DGK) phosphorylates and converts DAG to phosphatidic acid. DGK regulates cellular DAG levels and attenuates DAG signaling. The 10 mammalian DGK isoforms have been identified to date. In cardiac myocytes, DGKalpha, epsilon, and zeta are expressed, and DGKzeta is the predominant isoform. DGKzeta inhibits protein kinase C (PKC) activation and subsequent hypertrophic programs in response to endothelin-1 (ET-1) in neonatal rat cardiomyocytes. DGKzeta blocks cardiac hypertrophy induced by G protein-coupled receptor agonists and pressure overload in vivo. DGKzeta attenuates ventricular remodeling and improves survival after myocardial infarction. These data provide a novel insight for subcellular mechanisms of cardiac hypertrophy and heart failure, and DGKzeta may be a new therapeutic target to prevent cardiac hypertrophy and progression to heart failure.     

Elevated serum fibrin-monomer levels are associated with high long-term cerebrovascular event rates in acute ischemic stroke patients.

BACKGROUND: Serum fibrin-monomer (FM) is a precursor of stable fibrin, and is a sensitive marker of a systemic hypercoagulable state. It has been reported that, in patients with acute ischemic stroke, higher levels of serum FM reflect intracardiac thrombus formation. METHODS AND RESULTS: Serum coagulation and fibrinolytic activity were measured in 113 patients with acute ischemic stroke within 7 (6+/-1) days after onset. The patients were followed for a mean of 354 (range 36-585) days. The primary endpoints were ischemic stroke recurrence with/without death. FM was markedly higher in the 19 cases with stroke recurrence (49.6+/-53.6 microg/ml) than in the 94 patients without stroke recurrence (14.6+/-30.5 microg/ml; p=0.008). The cerebrovascular event rates were markedly higher in the 12 cases with FM > or =16.5 microg/ml (37.5%) than in the 7 cases with FM <16.5 microg/ml (8.6%; p<0.001). Cox proportional hazards multivariate analysis showed that the FM level was an independent predictor of ischemic stroke recurrence with/without death (hazard ratio, 1.516 per + 1 standard deviation increase; 95% confidence interval, 1.042-2.180; p=0.036). CONCLUSIONS: Elevated serum FM levels in hospitalized ischemic stroke patients may be associated with a persistent systemic hypercoagulable state and high long-term rates of cerebrovascular events.     

Low T3 Syndrome Is Associated With High Mortality in Hospitalized Patients With Heart Failure

Background

We aimed to clarify the prognosis and pathophysiological parameters of low T3 syndrome in patients with heart failure (HF).

Subclinical Hypothyroidism Is Associated With Adverse Prognosis in Heart Failure Patients

Background

It is widely recognized that overt hyper- as well as hypothyroidism are potential causes of heart failure (HF). Additionally it has been recently reported that subclinical hypothyroidism (sub-hypo) is associated with atherosclerosis, development of HF, and cardiovascular death. We aimed to clarify the effect of sub-hypo on prognosis of HF, and underlying hemodynamics and exercise capacity.

Hemodialysis improves myocardial interstitial edema and left ventricular diastolic function in patients with end-stage renal disease: noninvasive assessment by ultrasonic tissue characterization

Congestive heart failure is the most common cause of mortality in patients with end-stage renal disease (ESRD). Ultrasonic tissue characterization with integrated backscatter offers a promising method for the noninvasive assessment of regional myocardial contractile performance and fibrosis. The aim of this study was to investigate the effect of hemodialysis (HD) on myocardial tissue characterization and left ventricular function in ESRD patients. We examined 26 patients with ESRD undergoing routine HD (age 63 ± 12 years, duration of HD 9.2 ± 3.2 years) and 30 patients with essential hypertension (HT; 60 ± 10 years). Routine echocardiographic parameters and the cyclic variation of ultrasonic integrated backscatter of the ventricular septum (CV-IBS) were measured. Left ventricular mass index was significantly larger in patients with ESRD than in those with HT (217 ± 56 vs 146 ± 45 g/m², P < 0.05). The indices for left ventricular diastolic function (E/A, the ratio of left ventricular peak early to late diastolic filling velocity; DT, the deceleration time of the early diastolic filling) and CV-IBS had deteriorated significantly in patients with ESRD before HD compared with those with HT (E/A, 0.6 ± 0.2 vs 0.9 ± 0.3, P < 0.05; DT, 228 ± 23 vs 184 ± 19 ms, P < 0.05; CV-IBS, 9.0 ± 1.3 vs 12.4 ± 0.9 dB, P < 0.05), possibly reflecting interstitial fibrosis. In patients with ESRD, HD reduced calculated left ventricular mass index by 19% (before HD, 217 ± 56 vs immediately after HD, 176 ± 45 g/m², P < 0.05) and CV-IBS by 19% (9.0 ± 1.3 vs 7.3 ± 1.1 dB, P < 0.05), that possibly reflected improvement of interstitial edema. HD also significantly improved indices for left ventricular diastolic function (E/A, 0.6 ± 0.2 vs 0.9 ± 0.2, P < 0.05; DT, 228 ± 23 vs 188 ± 21 ms, P < 0.05). HD improves myocardial interstitial edema and left ventricular diastolic function in patients with ESRD. Noninvasive assessment of ultrasonic tissue characterization is useful in defining the pathophysiological changes of ventricular myocardium in patients with ESRD. Received: December 17, 2001 / Accepted: April 19, 2002 Correspondence to O. Hirono