(n.) The chemical basis of ordinary connective tissue, as of tendons or sinews and of bone. On being boiled in water it becomes gelatin or glue.
Example Sentences:
(1) Collagen production of rapidly thawed ligaments was studied by proline incubation at 1 day, 9 days, or 6 weeks after freezing and was compared with that of contralateral fresh controls.
(2) The rate of accumulation of degraded LDL products was lower in collagen gel cultures, but the final levels achieved were the same in the two substrata.
(3) In the present study, the expression of type IV collagen associated with the basal membrane (BM) was studied histochemically (indirect immunoperoxidase-antiperoxidase) in cervical human papillomavirus (HPV) lesions (diagnosed using in situ DNA hybridization) of different grades.
(4) Both Types I and II collagen are important constituents of the affected tissues, and thus defective collagens are reasonable candidates for the primary abnormality in adolescent idiopathic scoliosis (AIS).
(5) Furthermore, overlap syndromes between the different autoimmune liver diseases as well as with other disorders including collagen disorders can be observed.
(6) When cultures were pulse labeled for 15 min and then incubated under chase conditions for 105 min, the amount of degraded collagen attained a value equal to approximately 20% of the amount synthesized during the labeling period; the data were fit with a simple exponential function that had a 40-min rise time and a 12-min lag time.
(7) At concentrations several hundredfold higher than the equivalents present in the minimum concentration of rat skin soluble collagen required for platelet aggregation, neither Hyl-Gal (at 29 muM) nor Hyl-Gal-Glc (at 18 muM) caused platelet aggregation or inhibited platelet aggregation by native collagen.
(8) However, cimetidine did not show any effect on the proliferation of collagenous fibers in the interstitial space of the mucosa.
(9) Electron microscopic observations of the masseter nerve in the aged cats revealed a disruption of the myelin sheaths and a pronounced increase in collagen fibers in the endoneurium and perineurium.
(10) The kinetic parameters for the hydrolysis of type I, II and III collagens have been measured and are similar in magnitude to those for the tissue collagenases.
(11) Increased amounts of laminin in the basal epithelium of the cornea and of collagen type III in the stroma and subepithelial components of the stroma were observed.
(12) The formation of auto-antibodies directed against laminin and type IV collagen is probably caused by restricted polyclonal B cell stimulation, a well known feature of trypanosomiasis.
(13) We found that when neutrophils were allowed to settle into protein-coated surfaces the amount of O2- they generated varied with the nature of the protein: IgG greater than bovine serum albumin greater than plastic greater than gelatin greater than serum greater than collagen.
(14) Pathologic examination demonstrates calcifications in the dead collagen that makes up catgut suture.
(15) Human Caco-2 enterocytes were cultured on matrix proteins (collagen I, laminin, fibronectin) with growth factors (epidermal growth factor [EGF] and transforming growth factor-beta 1 [TGF-beta 1]) and the tyrosine kinase and prostaglandin inhibitors genistein and indomethacin.
(16) In other experiments, the cells incorporated [3H]lysine into hydroxylysine residues of cell-associated collagen and then 32P into phosphohydroxylysine residues.
(17) On the other hand, ultraviolet (320-nm) light, absorbed by 3-hydroxy-pyridinium cross-links which were rapidly photolyzed, partially dissociated polymeric collagen aggregates from bovine Achilles tendon after subsequent heating.
(18) The drug was found to exhibit an ulcerostatic effect, to change the levels of collagen, noncollagen proteins, glycosaminoglycan fractions, DNA and RNA.
(19) Both enzymes are capable of catalyzing the refolding of thermally denatured type III collagen.
(20) Dissociated cerebral hemisphere cells from 4- to 7-day-old chick embryos were cultured either on a collagen or a polylysine substrate in a serum-containing medium.
Elastin
Definition:
(n.) A nitrogenous substance, somewhat resembling albumin, which forms the chemical basis of elastic tissue. It is very insoluble in most fluids, but is gradually dissolved when digested with either pepsin or trypsin.
Example Sentences:
(1) The contents of esterified cholesterol and elastin in the aorta were higher in the control group than in the milk-fed group by 28 an 94 per cent, respectively.
(2) After 6 weeks irradiation, the insoluble collagen and elastin were both substantially elevated, as were the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD).
(3) Similarities between the LIF spectra of atherosclerotic plaque and collagen and normal aorta and elastin were noted.
(4) The data supports the concept of the role of fibrin as the bonding factor in Phase I adherence and implies that collagen, rather than elastin, is primarily responsible for early graft adherence.
(5) Cells obtained from 12-day tissue remained monolayers for 4 to 8 days, after which time portions of the culture contracted into matrix containing chemically definable insoluble elastin and forming desmosine cross-links.
(6) Elastic fibers have been shown to contain two proteins, insoluble elastin and the elastic fiber microfibril, a glycoprotein.
(7) Dermal collagen, elastin, and glycosaminoglycans are altered.
(8) All large arteries contain elastin, collagen, and muscle which can be seen with light microscopy and transmission electron microscopy.
(9) The intracellular biosynthesis of elastin by connective tissue cells, such as smooth muscle cells, involves assembly of the polypeptide chains on the membrane-bound ribosomes, hydroxylation of some prolyl residues to hydroxyproline, and secretion of the polypeptides packaged in Golgi vacuoles.
(10) About 25% of elastin-bound elastase was found to be resistant to the inhibitory effect of alpha 1-proteinase inhibitor.
(11) Its antagonism to calcium is speculated to play a protective role in maintaining the extensibility of elastin.
(12) This accumulated matrix then served as the "substrate" for the exogenously added precursor elastin molecules.
(13) Our examination focused on the organization of elastin and collagen which are the major components of this tunic.
(14) These characteristics demonstrate that arterial smooth muscle cells are capable of synthesizing both soluble and cross-lined elastin in culture.
(15) The activity of lysyl oxidase which catalyzes the initial step of cross-linking of collagen and elastin polypeptides was measured in blood vessels of the hypertensive rat.
(16) Although the diet resulted in significant increases in levels of cholesterol, 25-OH vitamin D3 and calcium in plasma, increased levels of cholesterol and calcium in aortic tissue, and histological evidence of aortic lipid deposition, there were no detectable differences between experimental and control animals in either the rate or the time course of accumulation of total insoluble elastin in the thoracic aorta, or in the rate and time course of synthesis of soluble and insoluble elastin.
(17) Alkali hydrolysates of elastins contained a radioactive peak that was eluted between proline and leucine.
(18) Immunological co-localization of the carboxyl-terminal antibody with insoluble elastin in lung vasculature and parenchyma suggests that intact tropoelastin and not a processed form is incorporated into the elastin fiber.
(19) Adsorbed elastin has been found to be available as a substrate for purified enzymes, as well as for living melanoma cells (A2058 and B16-BL6), c-Ha-ras transformed rat embryo fibroblasts, and human pulmonary macrophages, as demonstrated by the release into the culture medium of lower molecular weight digestion products.
(20) This apparent increase in order occurs at the same temperature as an increase in order in aqueous solution and as a change in the volume expansion coefficient of fibrous elastin.