Epithelial cells and

Basic (pH) proteins directed against pathogens. Examples are the major basic protein from mast cells, the eosinophilic cationic proteins from eosinophils, and defensins from epithelial cells and neutrophilic granulocytes. 

Sites of endothelin-receptor expression. ETA receptors are expressed in the smooth muscle cells of the vascular medial layer and the airways, in cardiac myocytes, lung parenchyma, bronchiolar epithelial cells and prostate epithelial cells. ETB receptors are expressed in endothelial cells, in bronchiolar smooth muscle cells, vascular smooth muscle cells of certain vessels (e.g. saphenous vein, internal mammary artety), in the renal proximal and distal tubule, the renal collecting duct and in the cells of the atrioventricular conducting system. 

Non-neuronal cells (including astrocytes, mechan-osensory hair cells, macrophages, keratinocytes, endothelial cells of the vascular system, muscle cells, lymphocytes, intestinal epithelial cells and various cell-types of the lungs)... 

The ability of these peptidomimetic collagen-structures to adopt triple helices portends the development of highly stable biocompatible materials with collagenlike properties. For instance, it has been found that surface-immobilized (Gly-Pro-Meu)io-Gly-Pro-NH2 in its triple-helix conformation stimulated attachment and growth of epithelial cells and fibroblasts in vitro [77]. As a result, one can easily foresee future implementations of biostable collagen mimics such as these, in tissue engineering and for the fabrication of biomedical devices. 

Both influx and efflux transporters are located in intestinal epithelial cells and can either increase or decrease oral absorption. Influx transporters such as human peptide transporter 1 (hPEPTl), apical sodium bile acid transporter (ASBT), and nucleoside transporters actively transport drugs that mimic their native substrates across the epithelial cell, whereas efflux transporters such as P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), and breast cancer resistance protein (BCRP) actively pump absorbed drugs back into the intestinal lumen. 

Resistance to phagocytosis is sometimes associated with specific components of the cell wall and/or with the presence of capsules surrounding the cell wall. Classic examples of these are the M-proteins of the streptococci and the polysaccharide capsules of pneumococci. The acidic polysaccharide K-antigens of Escherichia coli and Sal typhi behave similarly, in that (i) they can mediate attachment to the intestinal epithelial cells, and (ii) they render phagocytosis more difficult. Generally, possession of an extracellular capsule will reduce the likelihood of phagocytosis. 

Particular strains of salmonellae (section 4.2) such as Sal. typhi, Sal. paratyphi and Sal. typhimurium are able not only to penetrate into intestinal epithelial cells and produce exotoxins but also to penetrate beyond into subepithelial tissues. These organisms therefore produce, in addition to the usual symptoms of salmonellosis, a characteristic systemic disease (typhoid and enteric fever). Following recovery frxm such infection the organism is commonly found associated with the gall bladder, hi this state, the recovered person will excrete the organism and form a reservoir for the infection of others. 

GERWIN B J, SPILLARE E, FORRESTER K, LEHMAN T A, KISPERT J, WELSH J A, PFEIFER A M, LECHNER J F, BAKER s J, VOGELSTEIN B et al. (1992) Mutant p53 can induce tumorigenic conversion of human bronchial epithelial cells and reduce their responsiveness to a negative growth factor, transforming growth factor beta 1 , Proc Natl Acad Sci USA, 89, 2759-63. 

Vitamin A is essential throughout life, including foetal development, but perhaps its most well researched role is that in vision where 11 -cis retinaldehyde is the initial part of the photoreceptor complex in rods and cones. Retinoic acid induces differentiation in epithelial cells and deficiency leads to... 

KLEIN R D and FISCHER s M (2002) Black tea polyphenols inhibit IGF-I-induced signaling through Akt in normal prostate epithelial cells and Dul45 prostate carcinoma cells , Carcinogenesis, 23 (1), 217-21. 

CP-channels with even smaller conductance have been described for the lacrimal and other exocrine glands [76,77]. These channels have a conductance of 1-2 pS. Unlike the ICOR-channel they appear to be blocked by millimolar concentrations of furosemide [77]. Most recent and only partially published data from my own laboratory obtained with the above modified nystatin technique [50,133,134] indicate that the respiratory epithelial cells and colonic carcinoma cells possess these types of small CP channels, and that these channels are involved in hormonal regulation of CP-conductance (cf. section 5). These CP-channels are regulated by cytosolic Ca. Hormonally induced increases in cytosolic Ca lead to an abrupt increase in the probability of these small CP-channels being open, yet they have no effect on the ICOR-channel. Data of this kind reinforce that the physiological importance of these small CP-channels may have been grossly underestimated. 

Estrogen enhances Candida adherence to vaginal epithelial cells and yeast-mycelial transformation this is supported by the fact that infection rates are lower before menarche and after menopause (except in women taking hormone replacement therapy), while rates are higher during pregnancy... 

Cholesteatoma A mass of keratinized epithelial cells and cholesterol resembling a tumor that forms in the middle ear or mastoid region. 

Wurbel MA, Philippe JM, Nguyen C, et al. The chemokine TECK is expressed by thymic and intestinal epithelial cells and attracts double- and single-positive thymocytes expressing the TECK receptor CCR9. Eur J Immunol 2000 30 262-271. 

Chantry D, Romagnani P, Raport CJ, et al. Macrophage-derived chemokine is localized to thymic medullary epithelial cells and is a chemoattractant for CD3(+), CD4(+), CD8(low) thymocytes. Blood 1999 94(6) 1890-1898. 

Aist JR, Liang H, Berns MW 1993 Astral and spindle forces in PtK2 cells during anaphase B a laser microbeam study. J Cell Sci 104 1207-1216 Bohm H, Brinkmann V, Drab M, Henske A, Kurzchalia TV 1997 Mammalian homologues of C. elegant PAR-1 are asymmetrically localized in epithelial cells and may influence their polarity. Curr Biol 7 603-606... 

Renal Effects. The characteristics of early or acute lead-induced nephropathy in humans include nuclear inclusion bodies, mitochondrial changes, and cytomegaly of the proximal tubular epithelial cells dysfunction of the proximal tubules (Fanconi s syndrome) manifested as aminoaciduria, glucosuria, and phosphaturia with hypophosphatemia and increased sodium and decreased uric acid excretion. These effects appear to be reversible. Characteristics of chronic lead nephropathy include progressive interstitial fibrosis, dilation of tubules and atrophy or hyperplasia of the tubular epithelial cells, and few or no nuclear inclusion bodies, reduction in glomerular filtration rate, and azotemia. These effects are irreversible. The acute form is reported in lead-intoxicated children, whose primary exposure is via the oral route, and sometimes in lead workers. The chronic form is reported mainly in lead workers, whose primary exposure is via inhalation. Animal studies provide evidence of nephropathy similar to that which occurs in humans, particularly the acute form (see Section 2.2.3.2). 

Ahir, A, Guo, L, Hussain, AA, and Marshall, J, 2002. Expression of metalloproteinases from human retinal pigment epithelial cells and their effects on the hydraulic conductivity of Bruch s membrane. Invest Ophthalmol Vis Sci 43, 458-465. 

Aukunuru, JV, Sunkara, G, Bandi, N, Thoreson, WB, and Kompella, UB, 2001. Expression of multidrug resistance-associated protein (MRP) in human retinal pigment epithelial cells and its interaction with BAPSG, a novel aldose reductase inhibitor. Pharm Res 18, 565-572. 

Lian, E, K. Q. Hu, R. M. Russell, and X. D. Wang. 2006. Beta-cryptoxanthin suppresses the growth of immortalized human bronchial epithelial cells and non-small-cell lung cancer cells and up-regulates retinoic acid receptor beta expression. Int J Cancer 119(9) 2084—2089. 

Coupled with CP reabsorption by way of transcellular (through the epithelial cell) and paracellular (in between the epithelial cells) pathways second half of the proximal tubule... 

Symons, L.E.A. (1965) Kinetics of epithelial cells and morphology of villi and crypts in the jejunum of the rat infected with Nippostrongylus brasiliensis. Gastroenterology49, 158-168. 

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