Tests of muscle power output: the role of body size.

The effect of body size on the output of the tests of directly assessed muscle power has been mainly ignored in the applied research. We hypothesized that the muscle power output would reveal a positive relationship with body size closely in line with the theoretical predictions, as well as that the strength of the studied relationship could justify standardized normalization procedures applied in routine testing. Male physical education students (n = 111) were evaluated in 10 standard tests of direct assessment of muscle power output. A standard allometric relationship P = A SB was applied to assess the relationship between the tested power output P and selected indices of body size S ( B = allometric exponent; A = parameter). The correlation coefficients obtained between the tested power output and body size ranged within 0.21 - 0.56 for body mass and 0.10 - 0.49 for body height. The mean (SD) values of the allometric exponents B obtained with respect to body mass and body height were 0.55 (0.15) and 1.15 (0.62), respectively. This relationship proved to be strong enough to merit applying a standard normalization. The normalization method should be based on body mass as a preferred index of body size, while the allometric exponent could correspond to the theoretically predicted one (i.e., B = 0.67).

Bovine haematological values during fattening with possible implications for muscle growth.

Haemoglobin concentration (Hb), haematocrit (PCV) and mean corpuscular haemoglobin concentration (MCHC) were determined as indicators of oxygen-carrying capacity in 25 Simmental bulls during intensive fattening. Their possible relations to muscle growth were also investigated. The animals were the progeny of two sires. Blood samples were taken at 6, 9, 12 and 15 months of age. After slaughter, the right thoracic rib cut (7-9) was dissected into the longissimus dorsi muscle (LD), other muscles (OM) and total muscles (TM) (LD+OM). There was a significant increase in the mean PCV and Hb values during fattening. The PCV and Hb values were significantly correlated with the tissue share of OM or TM only at 12 and 15 months of age. LD muscle share was not significantly correlated with any of the parameters at any fattening time. It would appear from these results that muscle growth proceeds in two phases. The first is until the age of 12 months and the other from then to maturity.

Micronization of drugs using supercritical carbon dioxide.

Particles from gas saturated solutions, a novel method for high pressure material processing, has been used for micronization of practically insoluble calcium-channel blockers nifedipine and felodipine and the hypolipidemic agent fenofibrate with the aim of increasing their dissolution rate and hence their bioavailability. Dependent on the pre-expansion conditions, a mean particle size of between 15 and 30 microm was achieved for micronized nifedipine and 42 microm for micronized felodipine. The particle size of processed fenofibrate, on the other hand, increased due to agglomeration. The highest dissolution rate was achieved by preparation of drug coprecipitates with PEG 4000.

Glutathione and related enzyme activities in the blood of Simmental bulls.

Blood glutathione (GSH) concentration and the activities of enzymes associated with glutathione metabolism, namely glucose-6-phosphate dehydrogenase (G6PD) and gamma-glutamyltransferase (gamma GT) were determined in thirteen intensively-fed Simmental young bulls at seven, 10, 12.5 and 15 months of age. When G6PD activity was highest, the GSH concentration had its lowest value and inversely. This suggests that NADPH is not completely spent on glutathione reduction. gamma GT activity increased significantly during fattening.