Mucus, viscous

Mucus Viscous glycoprotein, proteoglycan secretion of goblet cells and... 

Asthma is an extremely complex condition characterized by variable and reversible airways obstmction combiaed with nonspecific bronchial hypersensitivity (1 3). The cause of asthma, which is not always readily diagnosed (4), remains unknown. Days, if not weeks, ate needed to document the spontaneous reversal of the airways obstmction ia some patients. Asthmatics experience both an immediate hypersensitivity response and a delayed late-phase reaction, each mediated by a different pathway. Chronic asthma has come to be viewed as an inflammatory disease (5). The late-phase reaction plays a key role ia iaduciag and maintaining the inflammatory state which ia turn is thought to iaduce the bronchial hyperresponsiveness (6). The airways obstmction results from both contraction of airways smooth muscle and excessive bronchial edema. Edema, a characteristic of inflammatory states, is accompanied, ia this case, by the formation of a viscous mucus which can completely block the small airways. 

Schleim-bildung, /. slime (or mucilage or mucus) formation, -driise, /. mucous gland, gdrung, /. viscous fermentation. 

As under most circumstances progesterone action will hold primacy over estrogenic effects, the cervical mucus, endometrium, and probably the fallopian tubes reflect progestational stimulation. The cervical mucus becomes thick and viscous and thus impervious to spermatozoa. The endometrium is in a state that is not receptive for implantation of a fertilized egg. Probably, the progestational impact on the secretory activity and peristalsis in the fallopian tubes also assists the general contraceptive effect. It is difficult, however, to assess the relative contribution of the various effects to the... 

A number of clinical symptoms characterize cystic fibrosis. Predominant among these is the presence of excess sodium chloride in cystic fibrosis patient sweat. Indeed, measurement of chloride levels in sweat remains the major diagnostic indicator of this disease. Another characteristic is the production of an extremely viscous, custard-like mucus in various body glands/organs that severely compromises their function. Particularly affected are ... 

Oral mucosae are covered with mucus which serves as a link between the adhesive and the membrane. Mucus is a glycoprotein consisting of a large peptide backbone with pendant oligosaccharide side chains. The side chains terminate in sialic or sulfonic acids, L-fucose, sulfated galactose, or A -acetylglucosamine. The glycoprotein component imparts the viscous or gel-like (non-Newtonian) nature due to its capacity... 

Because the mucus layer or the underlying cells may serve as either final accumulation sites of toxic gases or layers through which the gases diffuse en route to the blood, we need simplified models of these layers. Altshuler et al. have developed for these layers the only available model that can be used in a comprehensive system for calculating tissue doses of inhaled irritants. It assumes that the basement membrane of the tracheobronchial region is covered with three discrete layers an inner layer of variable thickness that contains the basal, goblet, and ciliated cells a 7-Mm middle layer composed of waterlike or serous fluid and a 7-Mm outer layer of viscous mucus. Recent work by E. S. Boatman and D. Luchtel (personal communication) in rabbits supports the concept of a continuous fluid layer however, airways smaller than 1 mm in diameter do not show separate mucus and serous-fluid layers. 

The spermatozoa must swim through a viscous fluid (mucus) so that the drag will be significant. 

Mechanism of Action An expectorant that stimulates respiratory tract secretions by decreasing adhesiveness and viscosity of phlegm. Therapeutic Effect Promotes removal of viscous mucus. 

The viscous mucus layer provides a physical protective barrier for the mucosa trapping, binding, and clearing inspired particles. Approximately 1.5-2 L of mucus is secreted daily and the resultant gel layer varies between 5 and 10 pm in thickness. Mucus is composed of 95% water plus mucin glycoproteins (0.5%-5%), lipids in low proportions, mineral salts (1%), and... 

Chronic diseases include cystic fibrosis in which nasal mucus is thick and viscous as a result of abnormal chloride transport across the membrane of the epithelial cells, leading to reduced water secretion. Similarly, chronic sinusitis also reduces nasal mucociliary clearance due to an increase in the rheological properties of mucus. 

Mucus exists in the form of a viscous solution or a gel and is a sticky viscoelastic substance with water as its major constituent, accounting for 95 to 99.5 percent.101 Mucins are large (MW range 1000 to 40,000... 

Physical barrier. Following oral administration of macromolecular drugs, their potential absorption pathways from the intestinal lumen to the bloodstream can be classified into transcellular transport associated with adsorptive or receptor-mediated endocytosis and paracellu-lar transport (Fig. 10.1). The GI tract surface consists of a tightly bound single layer of epithelial cells covered with thick and viscous mucus, which serves as a defensive deterrent against permeation of xenobi-otics and harmful pathogens. The epithelial cells in the GI tract are... 

Mucus possesses both solid-like (elastic) and liquid-like (viscous) attributes simultaneously and is therefore termed a viscoelastic gel. The viscoelastic properties arise from the non-covalent interactions (entanglements) between the predominantly anionic mucin molecules, although weak hydrogen-bonding and ligand-like attractions between protein regions of adjacent molecules may also play a role. Gel properties are affected by ... 

Q5 Since a major problem in cystic fibrosis is production of very viscous mucus which is frequently infected, the cough reflex should not be completely suppressed. Failure to cough and at least partially clear the airways would cause secretions to be retained, forming obstruction and a focus for further infection. 

Patients with cystic fibrosis secrete very viscous mucus in the lung and suffer repeated lung infections. The pancreas is also affected and patients are deficient in pancreatic enzymes this reduces digestion and absorption of nutrients, so affecting growth. 

The viscous mucus in cystic fibrosis is difficult to clear from the lung patients need physical therapy and postural drainage to clear the airways. 

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