To determine whether patients at risk for paroxysmal atrial fibrillation could be detected while in sinus rhythm, the signal-averaged electrocardiogram triggered by P waves was recorded in 42 patients with paroxysmal atrial fibrillation (Paf group) and in 50 control patients. The root mean square voltages (LP10, LP20, and LP30) for the last 10, 20, and 30 msec and the duration (Ad) of filtered (40-300 Hz) P wave of the spatial magnitude were measured. LP10 and LP20 were significantly lower in the Paf than in the control group (LP10, 1.92 +/- 0.58 versus 2.49 +/- 0.78 microV, p less than 0.001; LP20, 2.47 +/- 0.78 versus 3.46 +/- 1.20 microV, p less than 0.0001), although no significant difference in LP30 was found between groups. Ad was also significantly longer in the Paf than in the control group (137.0 +/- 14.3 versus 118.6 +/- 11.3 msec, p less than 0.001). These differences between the Paf and control groups remained significant even after dividing by the presence or absence of organic heart diseases. The criteria of "LP20 = 3.5 microV or less" and "Ad greater than 120 msec" as defining "atrial late potential" gave a sensitivity of 91% and a specificity of 76%. These findings suggest that patients at risk for paroxysmal atrial fibrillation could be detected while in sinus rhythm by using the P wave-triggered signal-averaged electrocardiogram.

In this study, we detected several cytokines in GCF using a cytokine antibody array system, including both inflammatory cytokines and various growth factors. Therefore, periodontal disease may participate in the wound healing process and in tissue destruction via the inflammatory process. Our results suggest that the quantification of these cytokines in GCF provides useful information for the diagnosis of periodontal disease status.

Hepatocyte growth factor (HGF) acts as a mitogen, motogen, morphogen, anti-apoptotic factor, and scatter factor for various kinds of epithelial cells. It is a protein secreted by mesenchymal cells such as fibroblasts, and promotes motility and matrix invasion of epithelial cells. To clarify whether HGF is involved in periodontal disease, this study was conducted to determine whether HGF is present in gingival crevicular fluid (GCF) and to investigate the relationship between levels of HGF and the clinical parameters of periodontal disease, probing depth (PD), gingival index (GI) and bleeding on probing (BOP). We examined and collected GCF samples from 80 sites in 38 subjects with periodontal or other oral diseases. The concentrations of HGF, IL-1beta and PGE2 were determined by ELISA, and active collagenase activity was determined by functional assay. The HGF level correlated positively with PD and GI, and was significantly higher in specimens from BOP-positive sites and those where PD exceeded 4 mm compared with those from sites that were BOP-negative or with a PD less than 3 mm. There was a significant positive correlation between the concentrations of HGF and IL-1beta. These results indicate that the HGF level in GCF correlates well with clinical parameters of periodontal disease, and suggest that HGF may be involved in epithelial invasion through its role as a scatter factor.

Collateral channels that develop after a myocardial infarction do not reduce the infarct size or prevent left ventricular dilation within 1 month of infarction. In contrast, such collateral channels prevent subsequent ventricular dilation and the deterioration of left ventricular function over 2 years. However, our results may have been biased because of the small number of patients.

Recent studies have shown that the behavior of calcium in the epidermis is closely related to the conditions of the skin, especially the differentiation of the epidermal keratinocytes and the permeability barrier function, and therefore a correct understanding of the calcium dynamics is important in explaining epidermal homeostasis. Here we report on experimental observations of in vitro calcium waves in keratinocytes induced by mechanical stimulation, and present a mathematical model that can describe the experimentally observed wave behavior that includes finite-range wave propagation and a ring-shaped pattern. A mechanism of the ring formation hypothesized by our model may be related to similar calcium propagation patterns observed during the wound healing process in the epidermis. We discuss a possible extension of our model that may serve as a tool for investigating the mechanisms of various skin diseases.