Mucus salivary

MaePherson, L. M. D., and Dawes, C. (1991). Urea concentration in minor mucus gland secretions and the effect of salivary film velocity on urea metabolism by streptococcus vestibularis in an artificial plaque./Periodont. Res. 26, 395- 01. 

Table 3.1 for the putative carriers in saliva, urine and nasal mucus the N-terminal sequences are highlighted against the pig salivary protein. All lipocalins or similar uncharacterised ( 20kDa) fractions with biological activity are extracellular, often found in quantity, 5 g/ml protein in male mouse urine and with a relatively high negative charge. 

Figure 12.9 Salivary gland fixed in a glyoxal solution (Prefer, Anatech Ltd.). Membranes around mucus cells are unusually clear and nuclear chromatin is sharply defined. 

In addition to the intercellular lipids of the buccal mucosa, there appear to be other barriers which may reduce the ability of an exogenous compound to permeate the buccal mucosa. These include the salivary film and mucus layer, the basement membrane, and a metabolic barrier. 

The function of the mucosal pellicle is to serve as a barrier between the oral epithelial surface and the external environment, and so it may also act as a barrier to drug delivery. However, there are limited studies assessing the role of the mucus layer in buccal permeability. In one study, treatment of the oral mucosa with anticholinergic agents resulted in an increased permeability of certain compounds, and it was suggested that the reduced salivary flow may have been responsible for the reduced barrier properties of the tissue [113]. In... 

Stimulation of saliva production is under sympathetic and parasympathetic control. Parasympathetic stimulation produces a serous watery secretion, whereas sympathetic stimulation produces much thicker saliva. Drug delivery systems, therefore, should not be placed over a duct or adjacent to a salivary duct, as this may dislodge the retentive system or may result in excessive wash-out of the drug or rapid dissolution/erosion of the delivery system making it difficult to achieve high local drug concentrations. If a retentive system is placed over salivary ducts, the reduced salivary flow rate may produce less or no mucus which is required for the proper attachment of a mucoadhesive delivery device. 

Food is taken into the buccal cavity, where it is masticated by the teeth and mixed with saliva from three pairs of salivary glands. It moistens the food and dissolves some molecules enabling them to interact with the taste receptors on the tongue. Saliva contains Na% Cl and HCOs ions and a protein, mucin, which is a component of mucus that lubricates the chewed food on its way down the oesophagus. The pH of saliva is about 7.8, which neutralises acid formed by bacteria in the mouth this protects tooth enamel... 

Submucosa. The submucosa is a relatively dense connective tissue with a few accessory salivary glands (mucus acinus).102 The saliva is secreted primarily by parotid, submandibular, and sublingual glands at a rate of 0.5 to 2 L/day.94 Apart from water, saliva is composed of electrolytes, mucin (forms mucus with water), amylase, lysozyme (a bacteriostatic enzyme), IgA antibodies, and metabolic wastes such as urea and uric acid.18 The pH of saliva varies between 6.8 and 7.2.96... 

Raynal B.D., Hardingham T.E., Sheehan J.K. and Thornton D.J. (2003). Calcium-dependent protein interactions in MUC5B provide reversible cross-links in salivary mucus. J Biol Chem. 278, 28703-28710... 

The watery component of saliva moistens and lubricates the masticatory process. Salivary mucus helps to bind the food bolus ready for swallowing. The surface coating of mucus also serves to protect the epithelium from potentially harmful substances. Enzymes present in the saliva initiate the digestive process. 

Mucus and salivary clearance reduces the retention time of drags within the oral cavity and thus the opportunity for absorption. This may be overcome by the use of mucoadhesive systems. 

G26. Glass, G. B. J., and Boyd, L. J., Studies on dissolved mucin of the gastric juice. IV. Relationship of the mucoid of the visible gastric mucus, its split products, and the salivary mucin to the dissolved gastric mucoproteose and mucoprotein of the gastric juice. Bull. N. Y. Med. Coll. Flower Fifth Ave. Hosp. 12, 1-33 (1949). 

On a vitamin A-deficient diet, mucus-secreting tissues become keratinized. This condition tends to occur in the trachea, the skin, the salivary glands, the cornea, and the testes. When this occurs in the cornea, it can be followed by blindness. Vitamin A deficiency is the principal cause of blindness in the very young. This problem is particularly acute in the third world (8). 

Some glycoproteins, particularly those with numerous, generally distributed, oligosaccharide side-chains, are able to form dispersions with stringy characteristics, as in nasal mucus or salivary discharges. The rheological implications of interactions between mucus and dmgs have been studied. As yet there is no coherent view as to what the ideal mucolytic... 

Most tooth problems are directly related to dental plaque. This is a whitish substance that collects on teeth and gums, which is removed by brushing. About 70% of plaque is made up of millions of bacteria, which lodge in a mass of insoluble carbohydrate. Plaque starts with a deposit of salivary mucus on the teeth containing aerobic bacteria that need oxygen to develop. With time, anaerobic bacteria appear they are the principal cause of problems related to plaque. 

From the time of Langley s early experiments, physiologists knew that pilocarpine stimulates secretion of saliva rich in mucus. Stimulation of the parasympathetic nerves to the salivary glands does so as well, and to that extent pilocarpine is a parasympathomimetic drug. When Franklin Hollander reviewed the effect of pilocarpine upon secretion of mucus by the stomach in 1947, he found that reported experiments on human subjects had given rampantly inconsistent results. The same. 

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