Tracheal fluid

The surface tension of the tracheal wall in the normal rat, guinea pig, sheep, and horse is approximately 32-33 mN/m, substantially more than the plateau surface tension (23-25 mN/m) of alveolar surfactant extracts from mammalian lungs. These data are consistent with recent studies in the pig, using relatively pure extracts of tracheal fluid, that have shown that the surface tension properties of tracheal fluid are considerably less than those of BAL fluid (44). 

The reason(s) for the difference in equilibrium surface tensions of airway and alveolus are unknown, but they may reflect differences in the composition, concentration, or both, of the surfactant of the two compartments. As the rate of adsorption of lipids to the film interface depends on both the composition and concentration of the surfactant phospholipids and the associated surfactant proteins (23,65), the low SP-A and absent SP-B and SP-C in the pig tracheal fluid in the foregoing experiments (44) may account for the higher static adsorptions observed in the tracheal fluids from this species. 

Cigarette smoke induced tracheal hypersecretion. Prot. Biol. Fluids 32, 387-390. 

Johnson, H.G., McNee, M.L., Johnson, M.A. and Miller, M.D. (1983). Leukotriene C4 and dimethylphenylpiperazinium-induced responses in canine airway tracheal muscle contraction and fluid secretion. Int. Arch. Allergy Appl. Immun. 71 214-218. 

Siloxane-containing devices have also been used as contact lenses, tracheostomy vents, tracheal stents, antireflux cuffs, extracorporeal dialysis, ureteral stents, tibial cups, synovial fluids, toe joints, testes penile prosthesis, gluteal pads, hip implants, pacemakers, intra-aortic balloon pumps, heart valves, eustachian tubes, wrist joints, ear frames, finger joints, and in the construction of brain membranes. Almost all the siloxane polymers are based on various polydimethylsiloxanes. 

Lung/tracheal congestion, fluid in the pleural cavity, atelectasis, emphysema, and/or pulmonary edema and lung hemorrhaging were observed in rats... 

The chest radiograph may reveal a dilated esophagus with an air fluid level, changes of chronic aspiration and tracheal displacement (Fig. 2.21). The stomach... 

Much information concerning the assimilatory activity of roots comes from analyses of the sap collected from a bleeding root system or of the tracheal sap recovered by perfusion or vacuum extraction of shoot segments. The former system is utilized for herbaceous species, the latter for wood material. The fluid obtained is considered to be a xylem exudate although there is always a danger that the sample may be contaminated with phloem and the contents of living cells. 

Welsh, M.J., J.H. Widdiscombe, and J.A. Nadel, 1980. Fluid transport across canine tracheal epithelium. 

Trachea TE has been one of the most promising approaches to providing a potential clinical application for the treatment of long-segment tracheal stenosis. The sources of the cells are particularly important as the primary factor for TE. Besides autologous mature cells, various stem cells, including bone marrow-derived mesenchymal stem cells (MSCs), adipose tissue—derived stem cells, umbilical cord blood—derived mesenchymal stem cells, amniotic fluid stem cells, embryonic stem cells, and induced pluripotent stem cells, have received extensive attention in trachea TE [118]. 

Previous research has suggested that VA deficiency is associated with a reduction in the production of IgA such a decrease may be related to the often-increased severity of infections observed in VA-deficient children and the poor recovery of mucosal epithelia following infection in animal models (see chapter in this book by R. Semba). The IgA response to influenza A in VA-deficient mice was reduced in lung tissue, yet influenza A-specific IgG titers in tracheal and lung lavage fluids did not differ between VA-deficient and control mice [25]. 

Thus, this experiment demonstrates that, for particle immersion, the aqueous substrate on the trachea may be mimicked in vitro by a viscous newtonian fluid the density of which is higher than that of the particle, provided the surface tension of the surfactant film in the balance is the same as that at the tracheal wall-air surface. 

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