A study was designed to examine the effects of exercise intensity on renal clearance parameters. Five healthy male subjects underwent exercise tests on an bicycle ergometer at 4 different work loads for 15 min. The indicators of exercise intensity employed were the percentage of maximal oxygen uptake (%VO₂max), heart rate (HR) and blood lactate level (La) . As parameters of renal clearance, para-aminohippurate clearance (CPAH), thiosulfate clearance (C_thio) and creatinine clearance (C_cr) were measured by the continuous infusion technique during the exercise.
1) The renal clearance parameters during exercise decreased linearly as the exercise intensity increased. The percentage of maximal oxygen uptake at the onset of the decreases in %C_PAH, %C_chiu and %C_cr were 36, 45 and 47%VO₂max, respectively.
2) Among the indicators of exercise intensity, the decrease in La showed the closest correlation with renal clearance during the exercise.
3) The renal plasma flow, which was measured as C_PAH, began to decrease linearly at a significantly lower exercise intensity than the glomerular filtration rate, which was measured as both C_thio and C_cr.
The above results suggest that renal clearance parameters begin to decrease at the threshold as exercise intensity increases.

To promote habitual participation in physical activity, a 3-month program for lifestyle physical activity intervention (L group) and structured exercise intervention (E group) was carried out in a community in Okayama Prefecture. One year later, we compared the two intervention groups in terms of cost-effectiveness and behavioral change in habitual physical activity. A total of 250 subjects voluntarily participated in the lifestyle physical activity intervention ; and a total of 42 subjects participated in the structured exercise intervention. The number of participants decreased to 115 (46%) and 21 (50%), respectively, one year later. However, the proportion of subjects who practice endurance exercise increased significantly in both L and E groups ; and an additional 35 subjects (30%) started to practice endurance exercise in L group and 5 (24%) in E group after the interventions. The cost-effectiveness for a person newly starting the endurance exercise practice in the L group intervention was 29,206 yen ; and the E group intervention was 124,731 yen, a ratio of 1/4.3. The study suggests that the cost-effectiveness for the lifestyle physical activity intervention was 4 times better than the structured exercise intervention.

We report on a rare case of Marfan syndrome with giant dissecting descending thoracic and abdominal aortic aneurysms associated with poor left ventricular function and severe mitral regurgitation. Before the anesthetic induction, a partial extra-corporeal circulation was established to prevent a collapse of the circulation. Descending aortic graft replacement and following abdominal aortic graft replacement were performed safely using the partial extra-corporeal circulation to relief the afterload for the severely deteriorated left ventricle with severe mitral regurgitation. Intra-aortic balloon pumping was also promptly used to assist the poor circulation in the postoperative period. Despite the admission to a specialized institute, he died from irreversible heart failure with a developing renal failure. Even for a difficult patient with Marfan syndrome with severe left ventricular dysfunction and mitral regurgitation, graft replacement was feasible with meticulous perioperative circulatory management using partial extra-corporeal circulation and intra-aortic balloon pumping. However, a prompt registration for heart transplantation and an aortic surgery concomitant with implantation of left ventricular assisted device should have been considered to save the patient.