Search PubMed⌕ Search

Biomedical subjects

B Dufaux

Publications and source records attributed to B Dufaux.

9 recordsLinked to original sources
PubMed1991

Effect of a short maximal physical exercise on coagulation, fibrinolysis, and complement system.

In 11 healthy young subjects, the plasma concentrations of the thrombin-antithrombin III complex, fibrinopeptide A, tissue-plasminogen activator, complement fragments C3a and C4a, and histamine were measured before and after a graded maximal bicycle exercise test. The analyses were carried out 30 min before and immediately before exercise, immediately after exercise, and 30 and 60 min later. All post-exercise values were corrected for plasma volume changes, which were calculated from hematocrit and hemoglobin values. Immediately post-exercise, thrombin-antithrombin III, tissue-plasminogen activator, complement fragments C3a and C4a, and histamine were all significantly elevated (p less than 0.01), compared with the pre-exercise values; 30 and 60 min later the values normalized and significant differences from the pre-exercise values could no longer be measured. Fibrinopeptide A did not change significantly after exercise. The present results provide evidence for a simultaneous activation of coagulation, fibrinolysis, and complement system as well as for a release of histamine after a short maximal exercise.

Adult↗
PubMed1990

Lymphocyte subsets during the first hours and days after a 2.5 h running test.

After a 2.5 h running test on eight healthy young males the lymphocyte subsets in peripheral blood were analyzed by flow cytometry. The analysis was carried out immediately post-exercise, after a 1 h and 3 h interval as well as a one day, a two day and five day interval. Lymphocyte subpopulations were also measured in five control subjects who did not exercise. Compared with the pre-exercise level the total lymphocyte and T-cell count was decreased 1 h and 3 h after the run and one and two days after exercise (p less than 0.01). The absolute number of monocytes and B-lymphocytes fell significantly (p less than 0.01) on the first and second day after exercise. No consistent change of helper-/suppressor-inducer T-lymphocytes (CD4+) and cytotoxic-suppressor T-cells (CD8+) cells was observed immediately after exercise. One and 3 h later, however, the absolute number of both cell types dropped below pre-exercise values (p less than 0.01). The decrease of the CD8+ cells was more pronounced, causing an increase of the CD4+ to CD8+ ratio (p less than 0.01). Among the CD4+ cells only the Leu 8+ subpopulation showed a relative increase 1 h after the exercise (p less than 0.01) while the Leu 8- population remained unaffected. 1 h and 3 h after the end of the run there was a significant fall of the absolute number and percentage of natural killer cells (Leu 7+) and cytotoxic T-cells (CD8+ Leu 7+) (p less than 0.01). These cells remained low during the first and second day after the exercise (p less than 0.01). In the control subjects the changes of cell counts for all cells examined were much smaller than in the runners. The results indicate that strenuous and prolonged exercise causes a delayed redistribution of lymphocyte subpopulations with a reduction of lymphocytes and particularly of natural killer and cytotoxic cells beginning 1 h after the exercise followed by a reduction of monocytes 24 h later. The percentage increase of CD4+ cells 1 h after the exercise could be explained by an increase of the CD4+ Leu 8+ subpopulation.

Adult↗
PubMed1989

Complement activation after prolonged exercise.

The effects of a 2.5-h running test on the concentrations of the complement cleavage products C3a, C4a and C5a in plasma were examined in eight healthy young males. In all participants the C3a and C4a values were raised during (1 h after the start) and immediately after exercise. C4a was also raised 1 and 3 h after the race. These results provide evidence for complement activation after prolonged exercise.

Adult↗
PubMed1989

Plasma elastase-alpha 1-antitrypsin, neopterin, tumor necrosis factor, and soluble interleukin-2 receptor after prolonged exercise.

The effects of a 2.5-h running test on the plasma concentrations of elastase-alpha 1-antitrypsin, neopterin, tumor necrosis factor, and soluble interleukin-2 receptor were evaluated in eight healthy young male subjects. Neopterin was measured by radioimmunoassay, elastase-alpha 1-antitrypsin, tumor necrosis factor, and soluble interleukin-2 receptor by enzyme immunoassay. The post-exercise values were corrected for plasma volume changes which were calculated from hematocrit and hemoglobin values. Compared with the concentrations before exercise, elastase-alpha 1-antitrypsin values were significantly increased during the run (1 h after the start) (P less than 0.01) as well as during the first few hours after the end of the running test (P less than 0.01). A significant increase of tumor necrosis factor and neopterin was observed 1 h after the end and 1,3, and 24 h after the end of the running test, respectively, (P less than 0.01), and soluble interleukin-2 receptor concentrations were significantly elevated 1 and 2 days after exercise (P less than 0.01). The increase of elastase-alpha 1-antitrypsin, neopterin, tumor necrosis factor, and soluble interleukin-2 receptor supports the concept of a functional involvement of polymorphonuclear neutrophils and an activation of macrophages and T-lymphocytes after prolonged exercise.

Adult↗
PubMed1986

Delayed effects of prolonged exercise on serum lipoproteins.

The delayed lipoprotein changes after a 3-hour running test were examined in 14 moderately trained young male subjects. Fasting blood samples were obtained one day before, immediately before, and one, two, and four days after the race. Nonfasting samples were collected immediately after, one, and three hours after exercise. Three hours after the race, the ratio of unesterified cholesterol to cholesteryl esters was significantly increased, and one and two days after the race it was significantly decreased compared to the preexercise value. The HDL2/HDL3 ratio, measured by density-gradient ultracentrifugation was one and three hours after the running significantly elevated. However, no redistribution of the HDL2/HDL3 cholesterol ratio determined by a precipitation method with polyanions was found at this time. One day postexercise HDL cholesterol rose significantly above the preexercise value, and this was associated with an elevation of the HDL3 subfraction. On the following day a significant increase of HDL2 cholesterol and the HDL2/HDL3 cholesterol ratio was found. The apolipoproteins A-I, A-II, and B, measured by radial immunodiffusion, did not change during the first hours and the first two days after the race. On the second postexercise day the Lp(a) lipoprotein rose significantly above the preexercise value. Compared with the preexercise level the LCAT activity was significantly elevated three hours after the race and significantly decreased two days later. The present study suggests that during the first few days after prolonged exercise a number of plasma lipoprotein changes take place that are similar to those observed after a period of physical training.

Adult↗
PubMed1985

Assessment of circulating immune complexes by a solid-phase C1q-binding assay during the first hours and days after prolonged exercise.

A sensitive and specific solid-phase C1q-binding assay using porcine C1q and microtitre plates as a solid phase, served to assess the immune complexes in serum during the first hours and days after a 3-h running test. Fourteen moderately trained male subjects participated in the race and covered 36.3 +/- 3.7 (mean +/- SD) km in 3 h. Blood samples were drawn 1 day before, immediately before, immediately after, 1 and 3 h after and 1, 2 and 4 days after the race. When corrected for the changes of serum total protein, the apparent immune complex concentrations were 1 and 3 h after the race significantly higher (p less than 0.001 and p less than 0.05 respectively) than the pre-exercise values. Two days after the race the values were significantly lower (p less than 0.05) than before the race. These findings provide evidence for the formation of immune complexes after severe physical exercise.

Adult↗
PubMed1977

Modifications of serum glycoproteins the days following a prolonged physical exercise and the influence of physical training.

Eight male subjects (mean age 24.1 +/- 2.6 years) performed at intervals of 2 weeks successively a 3 h and two 2 h runs of different running speed. The days following the running there were moderate elevations of C-reactive protein, haptoglobin, alpha-1-acid glycoprotein, coeruloplasmin, transferrin, alpha-1-antitrypsin and plasminogen. There were small or no changes of albumin, alpha-2-macroglobulin and hemopexin. The elevations of the "acute phase reactants" were examined in three male subjects following a 2 h run before and after an endurance training period of 9 weeks. This demonstrated a decreased acute phase response after training as illustrated by the changes of C-reactive protein, haptoglobin and alpha-1-acid glycoprotein in spite of higher posttraining running speeds. Well-trained athletes have elevated levels of the serum protease inhibitors alpha-1-antitrypsin, alpha-2-macroglobulin and C1-inhibitor. These antiproteolytic glycoproteins might limit exercise-induced inflammatory reactions.

Adult↗