Nasal lining

Ciliated cells have small membranous projections (cilia) that contain interior contractile proteins cilia beat in synchrony and serve to sweep away foreign particles on the surface of the respiratory tract, i.e., in the lungs and the nasal lining. 

Try not to blow the nose for 20 minutes after the application to allow maximum contact of the drops with the nasal lining. 

Nasal sprays may be used to treat the nasal lining directly. Examples include ... 

If a steroid spray is to be used for inflammation and the nasal passages are blocked, the use of a decongestant nasal spray prior to the first uses of the steroid spray can clear the nostrils, ensuring that the steroid spray is delivered to the nasal lining. 

Symptoms are diminished by blocking the ability of the virus to bind with the nasal lining. 

Local host defenses of both the upper and lower respiratory tract, along with the anatomy of the airways, are important in preventing infection. Upper respiratory defenses include the mucodliary apparatus of the nasopharynx, nasal hair, normal bacterial flora, IgA antibodies, and complement. Local host defenses of the lower respiratory tract include cough, mucodliary apparatus of the trachea and bronchi, antibodies (IgA, IgM, and IgG), complement, and alveolar macrophages. Mucus lines the cells of the respiratory tract, forming a protective barrier for the cells. This minimizes the ability of organisms to attach to the cells and initiate the infectious process. The squamous epithelial cells of the upper respiratory tract are not ciliated, but those of the columnar epithelium of the lower tract are. The cilia beat in a uniform fashion upward, moving particles up and out of the lower respiratory tract. 

Clinical improvement should be evident by 72 hours of therapy, as demonstrated by defervescence, reduction in nasal congestion and discharge, and improvements in facial pain or pressure and other symptoms. Patients should be monitored for common adverse events and referred to a specialist if clinical response is not obtained with first- or second-line therapy. Referral is also important for recurrent or chronic sinusitis or acute disease in immunocompromised patients. Surgery may be indicated in complicated cases. 

Radon daughters are deposited on the surface of mucus lining the bronchi. It is generally assumed that the daughter nuclides, i.e. polonium-218 (RaA), lead-214 (RaB) and bismuth-214 (RaC), remain in the mucus and are transported towards the head. However, one dosimetric model assumes that unattached radon daughters are rapidly absorbed into the blood (Jacobi and Eisfeld, 1980). This has the effect of reducing dose by about a factor of two. Experiments in which lead-212 was instilled as free ions onto nasal epithelium in rats have shown that only a minor fraction is absorbed rapidly into the blood (Greenhalgh et al., 1982). Most of the lead remained in the mucus but about 30% was not cleared in mucus and probably transferred to the epithelium. 

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