Effect of temperature and/or sweetness of beverages on body composition in rats.

Sweetened beverages are mainly consumed cold and various processes are activated in response to external temperature variations. However, the effect of internal temperature variations through the ingestion of cold beverages is far from clear. Two experiments were conducted to investigate the effect of beverage temperature on body composition. Sprague-Dawley rats (5-6-week-old males) had free access to food and beverage for 8 weeks. Energy intake, body weight and body composition were monitored. In Expt 1, two groups of rats (n 9) consumed water at room temperature (NW about 22°C) or cold (CW about 4°C). In Expt 2, rats were offered room-temperature (N) or cold (C) sweetened water (10 % sucrose CSu (n 7) and NSu (n 8); or 0·05 % acesulfame K CAk (n 6) and NAk (n 8)) for 12 h, followed by plain water. Our results show that in Expt 1, CW had higher lean body mass (P < 0·001) and lower body fat gain (P = 0·004) as compared with NW. In Expt 2, body weight (P = 0·013) and fat (P ≤ 0·001) gains were higher in the non-energetic sweetened groups, while lean body mass was not affected by the type of sweeteners or temperature. In conclusion, cold water ingestion improved lean body mass gain and decreased fat gain because of increased energy expenditure, while non-energetic sweetener (acesulfame K) increased body fat gain due to improved energy efficiency. Internal cold exposure failed to increase energy intake in contrast to that of external cold exposure.

[Renal Doppler ultrasonography in the diagnosis of acute obstructions of the upper urinary tract]. / Apport du Doppler rénal dans le diagnostic des obstructions aiguës du haut appareil urinaire.

A comparative study of the resistivity indices (RI) obtained in both kidneys has been carried out in 30 controls and 60 patients with suspected unilateral acute obstruction of the upper urinary tract. Doppler findings (difference in the mean RI of both kidneys, delta RI) in the pathologic population have been systematically correlated to the data yielded by intravenous pyelography (IVP). In the control population delta RI was always < or = 0.03 (mean delta RI = 0.01, SD = 0.01). Considering that an increase in delta RI > or = 0.05 (> mean RI + 3 SD) is significant, 93% sensitivity and 100% specificity are obtained for the diagnosis of unilateral acute obstruction. Comparison of the resistivity indices of both kidneys is more specific and more sensitive than the assessment of the index on the obstructed side only; it improves the performance of ultrasonography in the initial diagnosis of acute urinary tract obstruction.