Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A dentin biopsy technique was employed to compare the morphological features of hypersensitive and non-sensitive human radicular dentin. Specimens sampled from different areas in the same root surface displaying hypersensitivity or non-sensitivity were prepared for examination in the scanning electron microscope (SEM). Before analysis some specimens were exposed to surface demineralization and digestion of collagen to allow observation of subsurface portions of the dentinal tubules. In another set of observations the potential of a light-curing resin liner to penetrate root dentin in vitro and to maintain tubular occlusion over time following treatment of hypersensitive radicular dentin were examined. Orifices of many dentinal tubules were open in hypersensitive regions while non-sensitive areas generally displayed tubules occluded with mineralized material. SEM-images of HCl-collagenase treated specimens demonstrated the frequent presence of membrane-like structures in tubules of hypersensitive dentin. In non-sensitive dentin these structures were sparse. Topical application of a light-curing resin liner to wedge shaped defects prepared in radicular dentin of extracted human teeth resulted in a surface coating with a resin thickness of 20-50 microns. Resin penetrated dentinal tubules to a depth of more than 5 microns. Dentin biopsies examined 6 months after treatment with the liner showed presence of resin-like material in a majority of the tubules in dentin where hypersensitivity was no longer perceived. In none of the specimens did the liner remain as a surface coating. In areas of recurrent hypersensitivity more than half of the tubules presented with open orifices.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Morphological characterization of hypersensitive human radicular dentin and the effect of a light-curing resin liner on tubular occlusion. 138 27

To determine whether immune complex-like material is incorporated into the extracellular matrix (ECM) of proliferated RA synovium, cell-free matrices were isolated from pannus removed at joint replacement surgery, and were subjected to differential extraction. When the IgG and albumin concentrations in the ECM extracts were compared to those in simultaneously obtained synovial fluids, the IgG was found to be enriched 8.8-fold. Approximately 95% of the IgG was extractable with 6M Guanidine-HCl and 8 M Urea-B-ME. Further extraction with collagenase and low-pH buffers did not result in any additional recovery of IgG. Matrix-associated IgG demonstrated a restricted mobility on IEF with a pI of 4.8. The extracellular matrix of RA pannus is enriched in an acidic IgG species. Incorporation of IgG appears to be secondary to non-covalent interactions and may represent an additional reservoir of immune complex material in the rheumatoid joint.
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PMID:Synovial extracellular matrix II. Specific incorporation of immunoglobulin into the cell-free matrix of pannus. 139 21

Samples from the ascending aortae from two calves affected by bovine Marfan syndrome were subjected to biochemical analyses of the connective tissue and were compared to age-matched controls. Elastin was extracted from the aortic samples with 5 M guanidine-HCl, bacterial collagenase digestion, and dithiothreitol reduction. Amino acid analysis revealed that desmosine and isodesmosine levels were the same in Marfan calves as in control animals. Gravimetric measurements of elastin, amino acid composition, soluble protein, and uronic acid values also showed no significant difference between Marfan and control tissue. In contrast to elastin, collagen in aortae of Marfan calves was significantly higher than the mean of several controls. These findings, along with other observations of this animal model, support the conclusion that the microscopic and biochemical lesions of aortic elastin in bovine Marfan syndrome likely result from defective microfibrillar metabolism. Absence of cystic medial necrosis in bovine Marfan aortae may explain normal elastin content in the animal model.
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PMID:Normal elastin content of aorta in bovine Marfan syndrome. 142 58

Transamidases are a class of calcium-dependent mammalian enzymes which cross-link proteins by catalyzing the formation of (gamma-glutamyl)-epsilon-lysine bonds. It is possible that these enzymes play an important anabolic role in tissue healing. This study was to quantitate transamidase activity in human gingival tissue and examine the relation between transmidase activity and degree of inflammation. Forty-four out of a total 120 collected human gingival specimens from healthy and diseased patients were selected based on histometric and microbiologic criteria. Specimens were minced and homogenized in 10 mM CaCl2 and then extracted for 30 min, in 50 mM tris-HCl buffer (pH 7.5) containing 100 mM CaCl2. Following low speed centrifugation at 4 degrees C, the supernatant solution was assayed for both transamidase and collagenase activities by radioactive amine incorporation, and digestion of tritiated collagen, respectively. Appreciable levels of transamidase and collagenase activities in healthy gingivae were found. These enzyme activities were significantly elevated in the diseased and healing tissues. Unlike other transamidases, calcium was required in the enzyme extraction process.
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PMID:Transamidase and collagenase activity in healthy and diseased human gingival tissues. 146 May 85

Mature (average patient age = 29.5 yr, closed apical foramen) and immature (average patient age = 17.5 yr, open apical foramen) root shards were placed in dialysis tubing and demineralized to completion using either 10% disodium EDTA plus protease inhibitors or 0.6 N HCl. The demineralized shards were re-extracted (five times) with 0.05 M tris-HCl, 1.0 M NaCl and then collagenase digested. No major differences were observed in chromatograms of extracts, re-extracts or collagenase digests from root shards demineralized in either way. In contrast, chromatograms of immature and mature roots showed qualitative differences. Chromatograms of mature roots demineralized in either way showed broader protein peaks and less organic phosphorus than those from immature tooth roots. A distinct band amid degraded phosphoprotein (150 K) was found in SDS-PAGE gels (7.5%) from EDTA-extracted immature tooth roots but not from mature tooth roots. Electroelution of this band revealed a typical phosphoprotein amino-acid profile containing increased aspartic acid and serine residues. Comparison of the total phosphoprotein and amino acid composition of extracts, re-extracts and collagenase digests revealed that phosphoprotein, serine and to a lesser extent aspartic acid were recovered in greater quantities from immature roots than mature tooth roots. These data suggest that the degree of maturation is crucial to the isolation of an intact phosphoprotein and provides additional evidence that human dentine phosphoprotein undergoes amino acid compositional changes during maturation.
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PMID:Comparison of phosphoprotein isolated from mature and immature human tooth roots. 147 54

The finding that osteoblasts synthesize collagenase has led to the hypothesis that bone cells play a major role in bone resorption by degrading the surface osteoid layer, thereby preparing the underlying mineralized bone for osteoclastic action. To further understand the mechanisms regulating osteoid removal, mouse calvarial osteoblasts were cultured on 14C-labelled type I collagen films and the abilities of (i) bovine bone matrix extracts and (ii) purified or recombinant human growth factors, to modify their collagenolytic behaviour were investigated. EDTA/Tris-HCl extracts of bone matrix containing growth factor activity, exerted a dose-dependent inhibition of type I collagenolysis by osteoblasts stimulated with 1,25-dihydroxyvitamin D3 (1,25(OH)2D3, 10 ng/ml). Inhibition was accompanied by a reduction in collagenase activity and an increase in free TIMP (tissue inhibitor of metalloproteinases) in the culture medium. Transforming growth factor-beta, epidermal growth factor, platelet-derived growth factor and the acidic and basic fibroblast growth factors all mimicked these effects. In contrast, insulin-like growth factors-I and -II did not inhibit type I collagenolysis, only partially inhibited collagenase activity, and did not stimulate TIMP production by either 1,25(OH)2D3-treated or untreated cells. These findings provide additional evidence for the tight control exerted on the proteolytic activity of osteoblasts and the importance of TIMP in its regulation. They suggest strongly that the conversion (coupling) of the initial resorptive phase of the bone remodelling cycle to one of deposition, may be mediated by polypeptide growth factors either produced locally by osteoblasts, or released by proteolysis from the bone matrix.
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PMID:Bone-derived growth factors modulate collagenase and TIMP (tissue inhibitor of metalloproteinases) activity and type I collagen degradation by mouse calvarial osteoblasts. 184 30

This experimental study assessed the use of a collagen-coated vicryl mesh tube to reconstruct the esophagus in growing piglets. Initial experiments, in which a segment of thoracic esophagus was excised and replaced by this prosthetic tube, resulted in all the animals succumbing to mediastinitis within the first 3-4 days. This was shown, at post-mortem, to be due to leakage of the prosthesis, secondary to acid reflux, resulting in dissolution of the prosthesis. The collagen-coated vicryl mesh was thereafter treated with glutaraldehyde and in-vitro studies showed that the glutaraldehyde-treated material exhibited a higher resistance to 0.01 M HCl at pH 2.0, when compared with untreated material. In addition, the glutaraldehyde-treated material also showed an increased resistance to digestion by bacterial collagenase. Further experiments to reconstruct the cervical esophagus in growing piglets were performed using the revised glutaraldehyde cross-linked collagen coated vicryl mesh tube. All the animals survived the procedure and the prosthesis were leakproof immediately post-operatively. The animals, however, developed severe stenosis at a mean of 11 days post-operatively. Attempts at neo-epithelialization of the graft were seen histologically. There was considerable granulation tissue and scar tissue formation on the mediastinal aspect of the graft. It is suggested that collagen coated vicryl mesh tube may find applications in the treatment of esophageal atresia only if the problem of stenosis of the prosthesis can be solved.
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PMID:Use of a collagen coated vicryl tube in reconstruction of the porcine esophagus. 185 14

Natural materials containing tannin were examined to determine whether they possessed any inhibitory activity against collagenase obtained from the culture supernatant of Bacteroides gingivalis. The collagenolytic activity was determined with Collagenokit CLN-100 (Collagen Technological Co., Tokyo) using FITC-conjugated collagen type 1. Among the test samples, only an aqueous extract of cacao (Theobroma cacao) bean husk strongly inhibited the bacterial collagenase. This inhibitory potency was at the same level as that of tetracycline-HCl.
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PMID:Inhibitory effects of aqueous extract of cacao bean husk on collagenase of Bacteroides gingivalis. 196 77

Thirty human aortas with varying degrees of atheroma graded macroscopically according to the WHO classification were taken at autopsy from subjects of different ages (24-86 years). Study by light microscopy showed aortas with an intact wall (4 subjects, 25-46 years) with a thin intima and regular elastic layers, and aortas with varying degrees of modification of the wall, where the intima was of varying thickness and the elastic fibers showed varying degrees of damage (moderate lesions: 5 subjects, 35-52 yrs; severe lesions: 21 subjects, 26-86 yrs). From each aorta, a 4-cm segment from the tunica media, free of atheromatous lesions, was defatted and subjected to successive treatment with EDTA-Tris, 6 M guanidine-HCl-Tris, 6 M guanidine-HCl-Tris-DTE and collagenase. The residues (EP residues) were subjected to amino acid (AA) analysis and transmission electron microscopy (TEM) study. In the young subject, the AA composition was similar to that of elastin and the TEM images were characteristic of this substance. In the aging subject, an increase in polar AA and a parallel decrease in apolar AA and crosslinks was noted. By TEM, the elastin was seen to be associated with abundant fibrillar material. Trypsin treatment of EP residues gave E residues, whose composition and TEM appearance were similar in all samples, corresponding to the standard composition of elastin and its classic appearance by electron microscopy. We suggest that the fibrillar material removed by trypsin is the morphological reflection of the chemical variations observed in the EP residues. These correspond to contamination of the elastin by a polar protein fraction. This contamination is closely correlated with age but not with the degree of atheroma. Thus the age-related chemical changes in elastin appear to be independent of the onset and evolution of atheromatous lesions. The 10-15 nm diameter of the contaminating fibrillar material suggests that may be the microfibrillar fraction of elastic tissue.
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PMID:Age-related changes in the elastic tissue of the human thoracic aorta. 217 15

We have developed a procedure which allows the isolation of secretion granules from fresh parathyroid glands. Following collagenase digestion of the tissue, the cells were broken with osmotic shock and a crude granule/mitochondrial pellet was obtained by differential centrifugation. Before loading this fraction onto a metrizamide density gradient it was subjected to brief sonication to disrupt the mitochondria. This procedure was necessary in order to achieve separation of the granules from the mitochondria during ultracentrifugation of the gradient. When the fractionated gradient was analysed for PTH by radioimmunoassay, three bands containing parathyroid hormone were found, at densities of 1.0, 1.05 and 1.18. Upon electron microscopic examination of the gradient fractions, granules were found only in those fractions containing hormone. A typical granule appearance was observed for two of the populations, but the third population (density 1.18), consisted of granules without membranes and which appeared less electron dense than those of populations 1 (density of 1.0) and 2 (density of 1.05). Moreover, the lack of a limiting membrane imparted a fuzzy appearance to the population 3 granules. When fresh tissue sections were examined as control samples, granules with and without membranes were also observed. Standard marker enzyme assays further confirmed that populations 2 and 3 were relatively free of other cellular contaminants, but population 1 contained endoplasmic reticulum and lysosomal material. Because the number of granules contained in this population is very small, we have not been successful in achieving further purification of population 1. Based on radioimmunoassay of extracts of each granule population, PTH was concentrated in population 3, while the other two contained lesser amounts. Interestingly, results obtained with a radioimmunoassay for SP-1 revealed a striking difference in the distribution of SP-1 in the three granule populations. This protein, which is also secreted by the parathyroid gland, was concentrated in population 1 and 2. Only very low levels were found in population 3. Thus, the two major secretory products are localized in different granule populations. The isolated granules were stable to pH changes, cycles of freeze/thaw and sonication. The yields of PTH extracted from each of the granule populations by freezing and thawing in buffer or by Triton containing solutions were low. PTH was completely extracted from each population only by using 8 M urea in HCl. Lower concentrations of urea were less effective. These results indicate that the molecular architecture of the granules is highly resistant to disruption.
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PMID:The isolation and partial characterization of bovine parathyroid secretory granules. 233 91


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