Improved infrared-sensing running wheel systems with an effective exercise activity indicator.

This paper describes an infrared-sensing running wheel (ISRW) system for the quantitative measurement of effective exercise activity in rats. The ISRW system provides superior exercise training compared with commercially available traditional animal running platforms. Four infrared (IR) light-emitting diode/detector pairs embedded around the rim of the wheel detect the rat's real-time position; the acrylic wheel has a diameter of 55 cm and a thickness of 15 cm, that is, it is larger and thicker than traditional exercise wheels, and it is equipped with a rubber track. The acrylic wheel hangs virtually frictionless, and a DC motor with an axially mounted rubber wheel, which has a diameter of 10 cm, drives the acrylic wheel from the outer edge. The system can automatically train rats to run persistently. The proposed system can determine effective exercise activity (EEA), with the IR sensors (which are connected to a conventional PC) recording the rat exercise behavior. A prototype of the system was verified by a hospital research group performing ischemic stroke experiments on rats by considering middle cerebral artery occlusion. The experimental data demonstrated that the proposed system provides greater neuroprotection in an animal stroke model compared with a conventional treadmill and a motorized running wheel for a given exercise intensity. The quantitative exercise effectiveness indicator showed a 92% correlation between an increase in the EEA and a decrease in the infarct volume. This indicator can be used as a noninvasive and objective reference in clinical animal exercise experiments.

Prevalence of hyperuricemia and its association with antihypertensive treatment in hypertensive patients in Taiwan.

BACKGROUND: Hyperuricemia is thought to be associated with an increased risk of hypertension, impaired renal function and cardiovascular disease. Our aim is to study the prevalence of hyperuricemia and its association with antihypertensive treatment in Taiwanese hypertensive subjects. METHODS: We recruited 2145 hypertensive subjects from 19 hospitals in four areas of Taiwan. We assessed the prevalence of hyperuricemia and determined the independent risk factors for raised serum uric acid level by multiple logistic regression analyses. RESULTS: Compared to the general population, hypertensive subjects in Taiwan had a higher prevalence (mean 35% in males, 43% in females) of hyperuricemia; this prevalence being 1.5- and 1.7-fold higher in males and females respectively. Uric acid levels; gout and prevalence of hyperuricemia were found to be highest in the younger age group (20-39 years) and no regional differences were noted. The most important risk factors for hyperuricemia were impaired renal function and diuretic use. Serum uric acid values correlated significantly with four quintiles of serum creatinine (p<0.0001) independent of diuretic use. Diuretic users had a significantly elevated serum uric acid and serum creatinine values than non-users. Among the patients given diuretics, hyperuricemia occurred in 44% of those given thiazides, in 56% of those given loop diuretics, and in 57% of those given aldosterone receptor blockers. CONCLUSIONS: Diuretic usage and renal function status have a strong impact on the prevalence of hyperuricemia in Taiwanese hypertensive subjects. It is still unclear, however, whether diuretics induce renal failure through elevating serum uric acid levels.