Electrophoretic mobility of individual molecules of alkaline phosphatase.

The electrophoretic mobilities and catalytic rates of individual molecules of bovine intestinal alkaline phosphatase were determined in CHES and borate buffers of identical pH using a capillary electrophoresis based method. Both properties were found to be heterogeneous. In the presence of CHES, the mobility and rate were found to be -1.9 ± 0.2 × 10-9 m2 V-1 s-1 and 9.8 ± 7.4 × 104 min-1 (N = 38), respectively. In the presence of borate, the mobility and rate were found to be -6.9 ± 0.5 × 10-9 m2 V-1 s-1 and 2.0 ± 1.3 × 104 min-1 (N = 41), respectively. The means and variances for both properties were found to differ significantly between the two buffers. The difference in average mobility was attributed to an increase in negative charge caused by borate complexing with the carbohydrate moieties attached to the enzyme. The difference in variance was attributed to heterogeneous complexation with borate due to heterogeneity in the glycosylation. The differences in mean values for the catalytic rate were attributed to the inhibitory effect of borate and the difference in variance may suggest that the KI of this binding may also be heterogeneous.

Influence of endurance training and marathon running on red cell deformability in HIV patients.

PURPOSE: This investigation assessed whether endurance training altered the red cell deformability (RCD) of male HIV patients. METHODS: Eight subjects (38 ± 9 years, BMI 23 ± 3.6 kg/m², highly active antiretroviral therapy) trained for a marathon run for the duration of one year. Each subject underwent an acute exercise test on a treadmill at the beginning of this study (baseline) and after four months of training. Blood samples were taken at rest (T0) and at the end (T1) of each exercise test, as well as before (T0) and after the marathon run (T1). RCD was measured using the Laser Assisted Optical Rotational Cell Analyzer (LORCA), the maximal elongation index (EImax) and shear stress at half maximal deformation (SS ½ were determined using the Lineweaver Burke model. RESULTS: No changes were observed in RCD and SS ½ between T0 and T1 in all measurements. EImax significantly increased between T0 baseline and T0 after four months of training (P < 0.05). Measurements prior to the marathon run revealed significantly decreased EImax and SS ½ values (P < 0.05). CONCLUSIONS: The intensity of training in pathophysiological diseases like HIV is dependent for the alterations in RCD and possible improvements in microcirculation.

Influence of a moderate physical activity intervention on red cell deformability in patients suffering from chronic obstructive pulmonary disease (COPD).

The present study investigates whether a moderate physical activity intervention may alter red cell deformability (RCD) of patients suffering from chronic obstructive pulmonary disease (COPD). Subjects (n = 10; age: 62 ± 4; body-mass index (BMI): 25.8 ± 7.5) performed a training regimen for 10 weeks. In the beginning of the study and after the training period, COPD patients underwent a WHO cycle ergometry test. Venous blood samples were taken before (T0), immediately after (T1) and 30 min after (T2) the intervention. RCD was measured with the laser-assisted optical rotational cell analyzer (LORCA). Significant improvements of the RCD were detected. The semi-maximal shear stress increased significantly. Acute exhaustion had no effect on RCD. Thus, the training period of 10 weeks influenced RCD.