Surface epithelial cells

Four major tissue layers, from the lumen outward, form the large intestine the mucosa, submucosa, muscularis externa, and serosa (Fig. 88-2). Complete replacement of surface epithelial cells occurs approximately weekly, with the total number of epithelial cells remaining constant in normal colonic tissue. As patients age, abnormal cells accumulate on the surface epithelium and protrude into the stream of fecal matter their contact with fecal mutagens can lead to further cell mutations and eventual adenoma formation.4... 

The surface epithelial cells of the small intestine are renewed rapidly and regularly. It takes about two days for the cells of the duodenum to be renewed completely. As a result of its rapid renewal rate, the intestinal epithelium is susceptible to various factors that may influence proliferation. Exposure of the intestine to ionizing radiation and cytotoxic drugs (such as folic acid antagonists and colchicine) reduces the cell renewal rate. 

Mucus is produced by the mucus neck cells and by the surface epithelial cells of the stomach wall. A thick layer of mucus adheres to the wall of the stomach, forming the gastric mucosal barrier. The function of this barrier is to protect the gastric mucosa from injury — specifically, from the corrosive actions of HCl and pepsin. Together with bicarbonate ion released into the lumen of the stomach, mucus neutralizes the acid and maintains the mucosal surface at a nearly neutral pH. 

Gregoire, L., Munkarah, A., Rabah, R., Morris, R. T., Lancaster, W. D. (1998). Organotypic culture of human ovarian surface epithelial cells a potential model for ovarian carcinogenesis. In vitro Cell Dev-An 34(8), 636-639. 

Walsh RJ, Reinot T, Hayes JM et al (2002) Nonphotochemical hole burning spectroscopy of a mitochondrial selective rhodamine dye molecule in normal and cancerous ovarian surface epithelial cells. J Lumin 98 115-121... 

Jeffery PK (1983) Morphologic features of airway surface epithelial cells and glands. Am Rev Respir Dis 128(2 Pt 2) S14—S20. 

Frank, G., Gorfien, J., Mendel, S., D Auria, P., Brodsky, L., and Noble, B., 1999. Comparison of staining methods to detect interleukin-1 beta an antigen presenting cells and surface epithelial cells in the tonsil. J. Histotechnol. 22 97-102. 

The surface epithelial cells, which secrete mucus and bicarbonate... 

He QY, Zhou Y, Wong E, Ehlen TG, Auersperg N, Chiu JF, et al. Proteomic analysis of a preneoplastic phenotype in ovarian surface epithelial cells derived from prophylactic oophorectomies. Gynecol Oncol 2005 98(l) 68-76. 

Ovarian cancer is believed to develop primarily from the surface epithelial cells, which proliferate to cover the exposed surface following ovulation. As a result, factors which prevent ovulation (i.e., increasing numbers of live births, incomplete pregnancies, use of oral contraceptives) are protective against ovarian carcinoma. 

Figure 1.5. Histological changes in liver and stomach (Reprinted from Ito et al. 2003, with permission from Elsevier), (a) The liver 2 hour after p.o. gambierol at 140 pg kg , showing prominent congestions of sinusoidal capillaries at the periphery. P = portal veins. C = central vein, (b) Stomach alterations in the same conditions. Mucosa showed ulceration and erosion sporadically. E surface epithelial cells, G gastric glands, L lamina propria.

Visible mucus forms the external layer of Hollander s so-called protective gastric mucous barrier (H28-H30). According to him, the internal layer of this barrier consists of the preformed mucosubstances contained within the juxtaluminal portion of the surface epithelial cells themselves. 

About 100 years ago Harley, followed by Pavlov, stated that mucus protects the stomach from the chemical action of its own gastric juice (see H28). The nature of the protective effect of this mucous layer has then been analyzed, studied, and discussed by many authors, pointing out the possible mechanisms of this protective action. The fact that over 13,000,000 surface epithelial cells secrete mucus, according to Fontaine (F7), and more than 3,000,000 glands are present in the pyloric area of the stomach, according to Policard, led to the acceptance of the protective role of mucus. 

Gastric juice contains a mixture of secretions from surface epithelial cells and gastric glands. Salts, water, pepsins, intrinsic factor, and mucus are main... 

Quirk, S.M., R.G. Cowan and S.J. Huber. Fas antigen-mediated apoptosis of ovarian surface epithelial cells. 

CYTOKERATIN 20 In the small intestine, CK20 stains only the highly differentiated small bowel villous entero-cytes (cytokeratin 18 stains the more immature basilar, proliferative zone cells). In the colon, CK20 stains only the surface epithelial cell layer. CK20 staining is more extensive and stronger in small bowel neoplasms than colonic carcinomas." ... 

Final digestion occnrs in the small intestine, whereby aminopeptidase activity is courtesy of the surface epithelial cells. The end product amino acids enter the portal bloodstream going from the intestine to the liver, for subsequent utilization. 

XIII CollSAl Transmembrane collagen Cell surfaces, epithelial cells... 

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