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    Contribuição ao estudo das técnicas de análise do muco relativo à máquina simuladora de tosse, armazenamento e ângulo de adesão
    (Universidade Federal de São Paulo (UNIFESP), 1997) Gastaldi, Ada Clarice [UNIFESP]; Jardim, José Roberto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The normal thin mucous layer that covers the tracheobronchial epithelium may have its properties altered whenever the epithelium is submitted to aggressions or disease states. In these cases the greater amount of mucus production and/or the changes in its physicalchemical conditions may impair its transportation. Approximately 20 years ago, methods for in-vitro studies of the physical properties and transportation of bronchial secretions have been developed with the objective to better understand its pathological alterations and to establish therapeutic measures. But despite the several studies published there is no uniformity concerning some basic technical procedures what make some studies to be no comparable. In the first experiment, the influence of variables tube diameters (4,6,8,10 and 12 mm) and lengths (13.4; 20; 26 and 30 cm), driving pressure (4.2 and 2.1 Kgf/cm2) and lenght of the time of gas release (0.25; 0.5 and 1 second) on viscoelastic gel displacement in a simulated cough machine model was analyzed. Each variable was tested 12 times, in a total of 1440 tests. It was shown that a larger displacement of the gel was associated with increased reduction of the tube diameter and increases in time of gas release and driving pressure. Displacement decreased with increase in tube lenght but without following a established pattern. The greatest displacements, varying from 16.1 to 19.4 cm, with the smallest variability, were obtained in the tube with 4 mm diameter and 30 cm lenght with a driving pressure of 4.2 Kgf/cm2 and time of gas release of 1 second, with resultant air flow of 7.85 L/sec. In the second experiment, the influence of the size of the sample on the mucus displacement was studied using the previously standardized model of simulated cough machine. Gel displacements with samples of 0.002, 0.004 and 0.008 gram were measured. Average displacement of 20 samples in each group was higher with increased weight; there was statistical significance between 0.008 g in relation to 0.002 g, with a 72% greater displacement in the first group. In the third experiment, the influence of temperature and lenght of time of storage on transportability and cellularity of frog mucus samples, were evaluated. Samples of frog mucus, each being divided into 10 portions, were frozen at - 20 and - 80 Celsius degrees and analyzed on day zero, 2, 10, 30 and 90 of storage. There was no significant difference in the results, regarding ciliary transportability on frog palate, displacement in the simulated cough machine and adhesion angle measurements concerning both temperature and lenght of time of storage. Also, cytological analysis did not show alterations compatible with cell degeneration, showing that all types of storage tested were satisfatory. In the fourth experiment, the measurement of the adhesion angle during 20 minutes, in nine samples of frog mucus were assessed at time zero and after 1,2,3,4,5,10,15 and 20 minutes. The 24 degrees average measured at zero moment is considered to be ideal for transportation on frog palate; there was a progressive decrease in the angle, with a mean of nine degrees at the end of 20 minutes. Measurements at zero, 2 and 3 minutes were not different among them but they were greater than the ones measured at 15 and 20 minutes (p < 0.05), which were not statistically different from each other. There was a significant negative correlation between the displacement measurements in the simulated cough machine and the adhesion angle assessed at 15 minutes (r - 0.7) (p < 0.05).