Purpose: This study evaluated the clinical utility of the highest bone scan index (BSI), among other BSIs, for each bone metastatic site in patients with bone metastatic castration–resistant prostate cancer (bmCRPC). Methods: Thirty patients, diagnosed with bmCRPC by bone scintigraphy, were included. Total BSI, the number of hot spots, and regional BSI on each hot spot from bone scintigraphy at diagnosis with bmCRPC were evaluated by VSBONE BSI®. Highest regional BSI was defined as the highest value among regional BSIs on each hot spot in each patient. Related factors to overall survival and skeletal-related events (SREs) were evaluated using the Cox proportional-hazards model. Results: The median follow-up time from diagnosis with bmCRPC was 29.0 months. During this time, 24 patients died, of which 22 patients died from prostate cancer. On univariate analysis, alkaline phosphatase (ALP) [Hazard ratio (HR): 5.96, 95% confidence interval (CI): 2.05–17.3] and highest regional BSI (HR: 2.01, 95% CI: 1.17–7.05) had significant correlation with overall survival. On multivariate analysis, ALP (HR: 4.79, 95% CI: 1.61–14.2) had significant correlation with overall survival. SREs were found in eight patients. Only the highest regional BSI (HR: 9.99, 95% CI: 2.46–40.6) significantly correlated with SREs on univariate analysis. Conclusion Highest regional BSI may provide important information regarding prognosis and SREs in patients with bmCRPC.

Objective. We investigated whether the aging-related decrease in gap junction expression affects myocardial response against ischemia-reperfusion injury of the rabbit myocardium. Methods. Isolated aged (≥135 weeks) or mature (15-20 weeks) rabbit hearts were perfused with Krebs-Henseleit solution via a Langendorff apparatus, and were divided into five groups as follows: 7 mature hearts served as mature controls (Group A), 7 mature hearts underwent ischemic preconditioning (IPC) consisting of two cycles of global ischemia for 5min followed by reperfusion for 5min (Group B), 7 aged hearts served as aged control (Group C), 7 aged hearts underwent IPC (Group D) and 7 mature hearts received 1mM of gap junction uncoupler heptanol for 5min (Group E). Then, all hearts were subjected to 1h of left anterior descending coronary artery occlusion followed by 1h of reperfusion. Left ventricular pressure, ischemic zone monophasic action potential and coronary flow were measured throughout the experiment and the infarct size (IS) was determined at the end of the experiment. Gap junction expression was investigated by the electron microscopy. Results. The IS of Group A was 39.1±3.8 (%) and that of Group B was 26.9±3.8 (%)^* (^*p<0.05 vs. Group A). The IS of Group C was 19.3± 1.6(%)^*. That of Group D was 43.6±5.8 (%)^# (^#p<0.05 vs. Group C). IS of Group E was 24.3±1.6 (%)^*. Electron microscopic findings demonstrated that gap junction expression in aged hearts was less prominent than in mature ones. Conclusion. These data suggested that aged myocardium might be more tolerant of ischemic insult than that of mature heart, and that the mechanism might be related to the aging-related change of gap junction expression.