tight junctions


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tight junctions

Junctions between cells the extracellular surface of whose cell membranes are joined. Tight junctions restrict molecular movement between cells.
References in periodicals archive ?
Tight junctions provide structural integrity to tissues and create highly polarized barriers with selective paracellular permeability to water, solutes, and larger molecules.
The intestinal mucosal barrier mainly consists of epithelial cells and intracellular junctions, of which tight junctions play the most important role.
Furuse, "The structure and function of claudins, cell adhesion molecules at tight junctions," Annals of the New York Academy of Sciences, vol.
Lipidsoluble molecules and gases readily diffuse across the BBB while larger, hydrophilic molecules are impeded by endothelial tight junctions [1].
Epithelial cells in fresh water, but not marine sponges, can be joined by tight junctions, conferring high transepithelial resistence (Adams et al., 2010), while cells in cnidarians are joined by septate junctions that impede movements of proteins between cells (Tucker and Adams, 2014).
Second oral NaB may improve the intestinal barrier function by nourishing the colonocytes (Meijer et al., 2010), increasing the expression of epithelial tight junctions (Ma et al., 2012; Peng et al., 2009) and mucins (Gaudier et al., 2004) in the colon.
Conversely, the paracellular transport mediating tight junctions, such as claudins, occludins and zonula occludens, have been described as fundamental for absorption of electrolytes and water in the small intestine, and are modulated by undernutrition as well (12,13,17-19).
Stability can be altered due to lactation stage (TSIOULPAS et al., 2007a), ionic calcium content in milk (TSIOULPAS et al., 2007b), alterations in the permeability of mammary gland cells tight junctions (STUMPF et al., 2013), among others.
There are some evidences indicating positive role of [Na.sup.+]/[K.sup.+]/ATPase during blastocyst formation in mouse including: (a) polarized dissemination of [Na.sup.+]/[K.sup.+]/ ATPase just before beginning of cavitation, (b) increased [Na.sup.+]/[K.sup.+]/ATPase subunits expression during morula to blastocyst conversion, (c) inhibitory effect of ouabain (as a [Na.sup.+]/[K.sup.+]/ATPase inhibitor) on blastocyst development in some mammalians, and (d) positive role of [Na.sup.+]/[K.sup.+]/ATPase in function of trophectoderm tight junctions (17).
Researchers identified at least seven common food additives that weaken "tight junctions" in the intestine.
In addition, the tight junctions that hold taste cells together form a nearly impenetrable barrier that restricts the movement of larger ions, making it difficult to directly compare how different-sized ions affect taste cell function.
Under the patent, the applications and rights cover self-assembling compositions and methods of making and using compositions for preventing bleeding; preventing the movement of bodily fluids, contaminants; preventing adhesions; treatment of leaky or damaged tight junctions; and reinforcement of weak or damaged vessels.