Biomedical subjects
Publications and source records attributed to M L Devalon.
Management of premenstrual syndrome (PMS) includes psychosocial as well as medical therapy. Nonmedical treatment involves patient education, physician and family support, stress reduction, and dietary changes. If these methods do not alleviate symptoms, drug therapy may be necessary. Because the exact cause of PMS is unknown, treatment is largely empirical. More research is imperative to improve therapy for patients with PMS.
Plasma dihydroxyphenylalanine (dopa) has been shown to originate in sympathetic neurons, and it has been suggested that plasma level reflects activity of tyrosine hydroxylase, the rate-limiting enzyme in the synthesis of catecholamines. In this study, we measured the effects of acute exercise and exercise training on the levels of dopa and catecholamines in the plasma of healthy, older individuals. Venous blood was drawn from 19 men, from 52 to 75 years of age, at rest, at a standard submaximal work load, at peak exercise, and 3 minutes after exercise on a cycle ergometer. Ten of 12 men then completed 12 to 16 weeks of supervised training, and seven continued normal activity. All 17 men were then retested. The seven control subjects subsequently underwent exercise training as above and were retested again. Levels of dopa and catecholamines in plasma samples were measured by high-performance liquid chromatography with electrochemical detection. Dopa levels at rest were considerably higher than free dopamine, epinephrine, and norepinephrine. During short-term exercise, levels of dopa and catecholamines increased. The absolute increase in dopa was greater than the increase in epinephrine or dopamine but was not greater than that in norepinephrine. After the training period, basal dopa levels increased significantly and correlated with the increase in peak oxygen uptake. There was no change in basal conjugated norepinephrine or dopamine levels with exercise or training, but the level of conjugated epinephrine decreased slightly. No changes occurred in levels of dopa or catecholamines in the untrained group. Free dopamine, norepinephrine, and epinephrine levels at peak exercise were increased after exercise training.(ABSTRACT TRUNCATED AT 250 WORDS)
In contrast to results with bacterial suspensions, phagocytosis of unopsonized bacteria readily occurs when bacteria are adhered to glass or plastic surfaces. However, in contrast to neutrophils, alveolar macrophages produced much less DNA denaturation as measured by acridine orange metachromasia of phagocytized Staphylococcus aureus. We have studied the phagocytosis of unopsonized surface-adherent S. aureus and the subsequent production of reactive oxygen species by peripheral blood neutrophils, monocytes, and alveolar macrophages. Phagocyte-free systems were then used to show the relationship of the reactive oxygen species produced by neutrophils and alveolar macrophages and the denaturation of unopsonized S. aureus DNA with acridine orange. Peripheral blood neutrophils, monocytes, and alveolar macrophages from normal human volunteers were added to vials with adherent S. aureus without opsonin. Bacterial uptake and luminol- and lucigenin-dependent chemiluminescence were measured. Neutrophils developed much greater luminol-dependent chemiluminescence than monocytes or alveolar macrophages. Compared with neutrophils and monocytes, alveolar macrophages developed significantly greater concentrations of superoxide, as measured by lucigenin-dependent chemiluminescence and ferricytochrome c reduction. These findings suggested that products of the myeloperoxidase-hydrogen peroxide-halide pathway were generated when peripheral blood neutrophils were stimulated and that alveolar macrophages primarily produced superoxide. When these reactive oxygen species were generated in phagocyte-free systems containing S. aureus, products of the myeloperoxidase-hydrogen peroxide-halide pathway produced denaturation of S. aureus DNA, whereas superoxide did not. Thus, differences in reactive oxygen species produced during phagocytosis may be related to the different capacities of neutrophils and alveolar macrophages to denature unopsonized adherent S. aureus DNA.