Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.4 (chondroitinase)
 2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histological aspects of cervical ripening were studied on the human uterine cervix during pregnancy. Cervical specimens were taken from 25 cases of cervical laceration of primiparous women immediately after delivery, 8 primiparous women whose cervixes opened 2-3 cm, and 5 cesarean-sectioned women with unripeness of cervix. The following histochemical techniques were used: alcian blue, azure A, hyaluronidase digestion, and chondroitinase ABC digestion. The collagen bundles disintegrated into fine fibers and also underwent quantitative changes during the ripening process of the cervix. The number of connective tissue cells was increased during pregnancy, but that of mast cells was decreased. In late pregnancy, acid mucopolysaccharides in the cervical ground substance were found to increase.
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PMID:Histological aspects of cervical ripening. 13 67

The interaction between a small dermatan sulphate proteoglycan isolated from human uterine cervix and collagen type I from human and rat skin was investigated by collagen-fibrillogenesis experiments. Collagen fibrillogenesis was initiated by elevation of temperature and pH after addition of proteoglycan, chondroitinase-digested proteoglycan or isolated side chains, and monitored by turbidimetry. Collagen-associated and unbound proteoglycan was determined by enzyme-linked immunosorbent assay after aggregation was complete. (1) The binding of proteoglycan to collagen could be explained by the presence of two mutually non-interacting binding sites, with Ka1 = 1.3 x 10(8) M-1 and Ka2 = 1.3 x 10(6) M-1. The number of binding sites per tropocollagen molecule was n1 = 0.11 and n2 = 1.1. The 0.1 high-affinity binding site per tropocollagen molecule indicates that the strong interaction between proteoglycan and collagen results from a concerted action of tropocollagen molecules in fibrils. Digestion of the proteoglycan with chondroitinase ABC did not affect these binding characteristics. (2) Proteoglycan did not affect the rate of fibrillogenesis, but increased the steady-state A400 by up to 90%. This increase was directly proportional to the saturation of the high-affinity type of binding sites. Neither isolated core protein nor isolated side chains induced a similar high increase in steady-state A400. (3) Electron micrographs showed that the fibril diameter was affected only to a minor extent, if at all, by the proteoglycan, whereas bundles of laterally aligned fibrils were common in the presence of proteoglycan. (4) Results obtained with human and rat collagen were similar.
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PMID:A study of the interaction in vitro between type I collagen and a small dermatan sulphate proteoglycan. 341 38