Female beagle dogs were treadmill trained 40 km/day at 5.5-6.8 km/h, 15% upgrade, 5 days/wk for 55 wk. With training, hepatic and red gastrocnemius (RG) total glutathione increased, glutathione peroxidase (GPX) and glutathione reductase (GRD) increased in all the leg muscles studied, and hepatic glutathione S-transferase (GST) activity increased. Joint immobilization (11 wk) did not affect GPX, GRD, and GST of RG, but total glutathione decreased. Male Han Wistar rats were treadmill trained 2 h/day at 2.1 km/h, 5 days/wk for 8 wk. With training, hepatic total glutathione and leg muscle GPX increased but GRD of RG decreased, perhaps because of an increased muscle flavo-protein breakdown during exhaustive training. gamma-Glutamyl transpeptidase was higher in the trained leg muscles. Exhaustive exercise decreased muscle gamma-glutamyl transpeptidase of only control leg muscle, depleted muscle (lesser extent in trained rats) and liver total glutathione of both groups, decreased GRD only in untrained RG, and increased hepatic GST. Endurance training elevated the antioxidant and detoxicant status of muscle and liver, respectively.

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In trained (long-distance runners) and untrained volunteers aged 22 to 57 years, basal plasma glutathione (GSH) concentration decreased significantly with increasing age. In most age groups basal GSH concentration of oxidized glutathione (GSSG) and lipid peroxides (LPO) was not influenced either by age or by training. Following acute physical exercise (bicycle ergometric test), which was maximal for each person and thus different in trained and untrained persons, plasma GSH, GSSG, and LPO concentrations were not changed at all in untrained volunteers. In trained persons, however, GSH concentration was significantly decreased by about 30%. Surprisingly, we observed a decrease in plasma LPO content by about 40%. GSSG content was not altered. The comparison with some physical-physiological parameters indicates that the changes in GSH and LPO concentrations depend on the extent of acute physical exercise rather than on previous training. Alterations of GSH and LPO in plasma could be of physiologic significance.

The effect of heat on lactoperoxidase activity in bovine milk was studied over a range of 68 to 76 °C. Values of residual enzymatic activity after different treatments were studied by kinetic analysis, obtaining D-values and the Z-value (3.1 °C). Denaturation of lactoperoxidase, measured by loss in activity, can be described as a 1st-order reaction. Rate constants were calculated, as was the energy of activation, which was 737.69 kJ/mol. Thermodynamic parameters were also calculated. The high value obtained for the variation in enthalpy of activation indicates that a high amount of energy is required to initiate denaturation, probably due to the molecular conformation of lactoperoxidase.

Decreasing the disparity between cervical cancer screening services provided and those recommended requires addressing the barriers, identified by local experts, which prevent uninsured women from accessing care. These challenges are being addressed through ongoing programs and collaborations.