Lung airways

Yeh, H.C. and G.M. Schum, Models of Human Lung Airways and Their Application to Inhaled Particle Deposition, Bull. Math. Biol. 42 461-480 (1980). 

Seaton, M.J., Plopper, C.G. Bond, J.A. (1996) 1,3-Butadiene metabolism by lung airways isolated from mice and rats. Toxicology, 113, 314-317... 

Bronchitis—inflammation of the bronchi (lung airways) resulting in persistent cough that produces considerable quantities of sputum (phlegm). Bronchitis is more common in smokers and in the areas with high atmospheric pollution. 

The main permeability barrier in the airways to blood pathway lies with the epithelium of the lung airway rather than the intersitium or endothelial lining of the capillaries. The epithelial permeability towards hydrophilic solutes is at least 10-fold lower than that of the endothelium. The epithelium of the lung is much more permeable than that of other mucosal routes. For example, less than 3% of an oral dose of sodium cromoglycate reaches the circulation whereas more than 70% is absorbed from the lung into the bloodstream after inhalation. 

There are some indications that mammals possess at least two H2O2 sensors. One is located in cells of the lung neuroepithelial bodies, being responsible for constriction of the lung airways when the H2O2 level rises [6,7]. The other performs the same function in the blood vessels, being found in cells of the carotid body [8-10]. 

K -channel>l AT on plasma membranei -> serotonint -> opening of lung airways... 

Five mechanisms govern particle deposition in lung airways, namely, inertial impaction, gravitational sedimentation, diffusion, interception, and electrostatic attraction.f Electrostatic charges enhance deposition by increasing attractive forces to airway surfaces. Melandri et found that the deposition of... 

Rawlins EL, Okubo T, Xue Y et al (2009) The role of Scgblal+ Clara cells in the longterm maintenance and repair of lung airway, but not alveolar, epithelium. Cell stem cell... 

Lungs - airway epithelium and maxillary sinus Human AAV2 [117-120, 121-124]... 

Hoover MD, Harkema JR, Muggenburg BA, et al. 1993. A microspray nozzle for local administration of liquids or suspensions to lung airways via bronchoscopy. J Aerosol Med 6 67-72. 

Fang, C. R, Wilson, J. E., Spektor, D. M., and Lippmann, M. (1993). Effect of lung airway branching pattern and gas composition on particle deposition in bronchial airways. III. Experimental studies with radioactively tagged aerosol in human and canine lungs. Exp Lung Res 19(3), 377-396. 

Three of the cell types in the epithelium have secretory functions. These cells are the mucous (goblet) cells, serous cells, and Clara cells. These cells contribute to the secretion of airway mucus, a complex mixture of water, glycoproteins, immunoglobulins, lipids, and salts. The secretion of mucus is a defense function that contributes to the removal of foreign objects from lung airways via the mucociliary transport process, as described in later sections of this chapter. Excess mucus secretion can be detrimental, however, since it can obstruct the movement of air through the airways and is a component of certain pulmonary diseases such as asthma, emphysema, chronic bronchitis, and cystic fibrosis. A hypertrophy of secretory cells in the epithelial layer of the airways is often characteristic of these diseases. 

Intensive care aims at the replacement or support of deficient central functions. Important functions are respiration and a sufficient cardiac and circulation function. Monitoring the gas exchange in intensive care especially of ventilated patients requires, in addition to gas analysis at several measuring sites in the body, information on the heart function, eg, heart rate, on the pressure of the circulation system, eg, arterial pressure, and on the actual utilization of the available amount of oxygen. With regard to the methods required to achieve information that is as complete as possible, the clinical task consists in the determination of gas concentrations or partial pressures in the gas phase of the lung, airways, and equipment hoses, in the transportation system of the blood, and in the tissue. In recent years there has been an increasing importance of non-invasive methods, as invasive procedures are combined with risk and additional stress for the patient. 

Johnson, R. P., Gold, A. J., and Freeman, G, (1958), Comparative lung-airway resistance and cardiovascular effects in dogs and monkey.s following parathioii and sarin intoxication. Am. J. Physiol. 192, 581-584,... 

The flow-resistive properties of the airways are of major relevance to aerosol therapy in that they directly influence the pattern of distribution and deposition of inhaled particles within the lungs. Airway resistance increases, and hence aerosol delivery will be reduced, if the airways become partially blocked or narrowed by factors such as bronchospasm, inflammation, or secretions. Small changes in airway caliber can have dramatic effects on airway resistance. In a healthy adult, airway resistance is approximately 0.2 kPa/L/s (2 cmHp/L/s)... 

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