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This lecture series explores the defense mechanisms of the lungs against atmospheric pollutants, including carbon monoxide, sulfur oxides, nitrogen oxides, hydrocarbons, and particulates. It also discusses the insidious effects of tobacco advertising, the damaging effects of cigarette smoke, and the mechanisms of aerosol deposition and clearance in the lung.
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Defense Systems of the Lung Lectures on respiratory physiology
Atmospheric Pollutants • Carbon monoxide • Sulfur oxides • Nitrogen oxides • Hydrocarbons • Particulates • Photochemical oxidants
Types and sources of pollutants Perfect Lung
Photochemical Oxidants hydrocarbons ozone, peroxyacyl nitrate, sunlight nitrogen oxides aldehydes, acrolein, etc.
Perfect Lung Examples of smog
Insidious effects of tobacco advertising Effects of cigarette smoke Carbon monoxide causes up to 10% hemoglobin “Tars” cause bronchial carcinoma Smoking causes chronic bronchitis, emphysema, bronchial carcinoma and coronary heart disease
Behavior of Aerosols in the Lung • Deposition • Clearance
Mechanisms of deposition of aerosol Perfect Lung
Sites of aerosol deposition Perfect Lung
Mechanisms of deposition of aerosol Perfect Lung
Mechanisms of deposition of aerosol Perfect Lung
Clearance of Deposited Particles • Mucociliary system • Alveolar macrophages
Impairment of Normal Mucociliary Function • Mucus: too much, or change in composition, e.g. chronic bronchitis, cystic fibrosis, asthma • Cilia: paralysis by toxic gases • bronchial epithelium destroyed • congenital defect of ciliary motion
Impairment of Normal Macrophage Function • Inhaled gases such as ozone, cigarette smoke • Toxic particles such as silica • Alveolar hypoxia, radiation, corticosteroids, alcohol ingestion