Environmental factors affecting Edwardsiella ictaluri-induced mortality of riverine ayu, Plecoglossus altivelis (Temminck & Schlegel)

We analysed the predisposing factors for Edwardsiella ictaluri infection in the riverine ayu Plecoglossus altivelis on the basis of environmental and epidemiological data obtained in a tributary to and the lower reaches of the Tama River, Japan, in July and August 2011-2015. Mortality of ayu due to E. ictaluri infection was observed only in the tributary in August 2012 and 2013; both periods were unusually hot. During these mortality events, daily average water temperatures rose approximately 3-4°C over 4-8 days, reaching the optimum temperature for E. ictaluri infection (>25°C) and approaching the upper tolerable limit for ayu (30°C). Diurnal water temperature ranges (DWTRs) in the tributary during the mortality events exceeded 6°C, which was 1-2°C greater than in the lower reaches. Experimental infection of ayu with E. ictaluri resulted in higher mortality when exposed to 6°C DWTR than to 4°C DWTR. Furthermore, water levels in the tributary were generally low in August 2012 and 2013 because of low rainfall. From these results, we conclude that unusually high-water temperatures combined with high DWTRs and low water levels drove riverine ayu mortality from E. ictaluri infection.

Doppler velocity histogram analysis of hepatocellular carcinoma

To study the characteristics of tumor blood flow, flow profiles from hepatocellular carcinomas (39 profiles) and normal hepatic arteries (23 profiles) were evaluated using velocity histograms obtained with Doppler ultrasound. The histograms were classified into three types: (1) high-peak, (2) flat, and (3) low-peak. Characteristically, the low-peak types and the flat types, with flows in opposing directions, were seen only in the tumor vessels. The turbulence in a phantom flow model was of the low-peak type. Spectral analysis revealed that the velocity profile of tumor blood flow was different from that of noncancerous flow and that tumor blood flow was characterized by turbulence.

[Non-surgical biliary drainage for cholelithiasis]

Non-operative methods to treat obstructive jaundice and cholangitis caused by cholelithiasis are endoscopic and percutaneous biliary drainage. Usually, endoscopic papillotomy and stone removal by basket catheter is available for treating choledocholithiasis. It is necessary to place a drainage catheter into the bile duct in patients who have severe cholangitis or remaining stones. On the other hand, percutaneous biliary drainage is useful in case of emergency and in patients reconstructed by the Billroth II method. Biliary drainage is necessary to treat severe cholangitis as soon as possible, for it sometimes causes endotoxin shock, disseminated intravascular coagulation (DIC) and multiple organ failure (MOF).

Changes in oxygen uptake-work rate relationship as a compensatory mechanism in patients with heart failure

To assess the compensatory change in oxygen uptake (VO2) kinetics during exercise in patients with heart failure, we performed cardiopulmonary exercise testing using a cycle ergometer in 29 cardiac patients and 18 normal subjects. The work rate increased linearly (1w/6sec) after a 4 min, 20w warm-up. The ratio of increase in VO2 to increase in work rate (delta VO2/delta WR) was determined by linear regression of VO2 plots. Cardiac output by dye dilution method and plasma norepinephrine concentration (NE) were measured at rest and 20w warm-up. VO2 at rest and at 20w warm-up and delta VO2/delta WR decreased significantly with increasing severity in NYHA functional classification. delta VO2/delta WR showed significant negative correlation to the difference in NE levels at rest and at 20w (r = -0.69, p less than 0.001). The delta values of arteriovenous O2 content difference, calculated using Fick's principle, and cardiac index from rest to 20w warm-up failed to show significant relationship to delta VO2/delta WR. These results suggest that the decrease in VO2 requirement in heart failure patients is due probably to blood redistribution during exercise as a compensatory mechanism for exercise intolerance.

The efficacy of aerobic exercise therapy on hypertensive patients with mild cardiac complications

To investigate the antihypertensive efficacy of aerobic exercise therapy in essential hypertensives, 20 patients underwent eight weeks of cycle ergometer training at anaerobic threshold (AT) point. Cardiopulmonary exercise testings with ramp protocol were performed before and at two/four/eight weeks during the training period in order to determine AT and to evaluate the changes in blood pressure (BP), heart rate (HR), oxygen uptake (VO2; ml/min/kg), and O2 pulse (ml/min/beat) during exercise. 75g glucose tolerance test (OGTT) was measured before and after exercise therapy. The mean values of systolic blood pressure, oxygen uptake, O2 pulse, before and after exercise therapy were as follows: systolic blood pressure at rest = 160 +/- 19 mmHg and 135 +/- 11 mmHg, systolic blood pressure at AT = 195 +/- 13 mmHg and 180 +/- 10 mmHg, oxygen uptake AT = 12.0 +/- 0.9 ml/min/kg and 14.4 +/- 1.0 ml/min/kg, O2 pulse at AT = 6.8 +/- 1.5 ml/min/beat and 7.6 +/- 1.88 ml/min/beat. After exercise therapy, systolic blood pressure decreased (p less than 0.01), while O2 pulse and VO2 increased (p less than 0.01). Hyperresponse of serum insulin to glucose also improved. These results show that aerobic exercise therapy at AT level has beneficial effects on high blood pressure and improves exercise tolerance and hyperresponse of serum insulin to glucose without any complications.