Cardiorespiratory function as assessed by exercise testing in patients with non-insulin-dependent diabetes mellitus.

Exercise testing was used to examine 19 cardiorespiratory diabetes mellitus patients, aged 32-68 years (body mass index, 27.8 +/- 4.8 kg/m2), and 16 healthy volunteers, aged 23-57 years (body mass index, 22.7 +/- kg/m2). A graded cycling exercise test was done, monitoring gas exchange, ventilation and heart rate. Values were significantly higher in the non-insulin-dependent diabetes mellitus (NIDDM) patients than in the controls for fasting blood glucose (P < 0.01), glycosylated haemoglobin (P < 0.01), body weight (P < 0.05) and body mass index (P < 0.05). The exercise testing produced values that were significantly lower in the patients with NIDDM than in the controls for percentage oxygen uptake (P < 0.05), maximum load (P < 0.05), maximum metabolic equivalent (P < 0.01) and maximum oxygen uptake per unit body weight (P < 0.01). Ventilatory capacity and forced expiratory volume at 1 sec did not differ significantly in the two groups. These results suggest that general fitness is diminished due to reduced cardiorespiratory function in patients with NIDDM.

Cardiorespiratory effects of weight reduction by exercise in middle-aged women with obesity.

The cardiorespiratory responses to weight reduction due to physical exercise were examined in fourteen women with obesity, aged 36 to 67 years (Body Mass Index, 32.4 +/- 1.5 kg/m2). The patients were instructed to exercise at approximately 60% of maximum oxygen uptake for 2 h every day for approximately 3 months. To evaluate physical strength, a graded cycling exercise test was performed both before and after the exercise period, monitoring gas exchange, ventilation, and heart rate. After the exercise period the body mass index and percentage fat both decreased by 11% and 18%, respectively (P < 0.001), although lean body mass did not change; maximum oxygen uptake and maximum heart rate did not change significantly, but peak ventilation equivalent, maximum metabolic equivalent and maximum load increased by 12%, 14% and 11%, respectively (P < 0.05, P < 0.001 and P < 0.001, respectively). Maximum oxygen uptake per unit body weight increased by 5% (P < 0.001). These results suggest that weight reduction as a result of exercise improves cardiorespiratory function in middle-aged women with obesity.

Sophisticated mesh filtration technique of a large-scale isolation of islets and their function.

A large-scale isolation of islets is required for islet transplantation. We improved our conventional method, and could obtain about three times more islets than by the conventional methods. Pancreata of adult Wistar rats were inflated by injection of buffer with (A) or without 1.3 mg/ml collagenase (B). The rats were bled from the inferior vena cava and the aorta in (A) simultaneously with the inflation. They were further digested with collagenase and filtered through two different meshes (pore size: 1190 and 590 microns) (A1) or three different meshes (pore size: 1190, 590 120 microns) (A2) in order. Insulin released from islets isolated in this manner was determined by 1-h incubation with 3.3 and 16.7 mM glucose. Besides, 600 islets each were transplanted into the liver of streptozotocin-induced diabetic Wistar rats and their fasting plasma glucose was measured at weekly intervals. (1) With these methods more numerous islets were harvested by A1 (mean: 554) and A2 (mean: 746) than B (mean: 224). (2) Insulin released at both glucose concentrations was similar among islets obtained by A1, A2 and B. (3) The plasma glucose-lowering effect was similar among the islets obtained by these methods. (4) A more selected range of islet sizes was obtained by A2 than A1. These observations indicate that the present techniques (A1 and A2) are less time-consuming and simpler for a large-scale isolation of islets.