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

Despite ingenious concepts, there are no unequivocal clues as to what, when, and how some undefined biochemical factor(s) or constituent(s) that localizes in the arterial wall can precipitate a thromboatheromatous lesion or arterial disease. The present study focused on the extraction, partial purification, and characterization of a collagen-active platelet stimulator from the aortas of aged burros. The aggregator moiety in the aorta extracts invariably had a higher affinity for platelets in citrated platelet-rich plasma of human beings than for platelets of homologous burros. The platelet-aggregating factor(s) in the aorta extract was retained by incubation with alpha-chymotrypsin. Platelet-aggregating activity was rapidldy abolished after incubation with collagenase, as determined by plateletaggregometry tests. Evidence based on light microscope and polysaccharide histochemical reactions indicates a probability that the intracellular amorphous matrix (PAS-positive) and filamentous components (PTAH-positive) expelled from smooth muscle cells disrupted during homogenization of the aorta may be a principle source of a precursor collagen species which is a potent inducer of platelet aggregation.
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PMID:Platelet affinity for burro aorta collagen. 20 Nov 88

A case report on a 6-year-old boy suffering from the extremely rare Hutchinson-Gilford syndrome (progeria) is presented. The results of histopathological and immunohistological examination of the scar-like skin lesions are reported. Subcutaneous amorphous nodules were eosinophilic, PAS- und elastica-negative und remained unstained with antibodies against collagen type IV, vimentin, and collagenase. The dense perivascular infiltration consisted of CD4+, CD8-, alpha-1-antichymotrypsin-, MAC 387-, and some vimentin-positive cells. Perinodular blood vessels were more abundant and had a thickened wall. Collagen bundles were swollen. The epidermis appeared atrophic with focal basal cell degeneration.
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PMID:[Hutchinson-Gilford syndrome]. 150 7

A new method for the primary monolayer cultures of adult rabbit gastric mucous cells has been developed. Rabbit gastric mucosal cells were isolated with etylenediaminetetraacetic acid and collagenase. Cells were cultured in Coon's modified Ham's F-12 medium supplemented with 10% fetal bovine serum, 15mM HEPES buffer, antibiotics, and antimycotic. The cells reached confluency on days 3-4. Histochemically 92% of the cells contained PAS positive gramules (mucous cells), 3% of cells showed a strong reaction for succinic dehydrogenase activity (parietal cells), 2% of the cells showed positive granules by Bowie staining (chief cells), and G6PDH staining was positive in 5% of the cells (surface mucous cells). Fibroblasts were rarely seen until day 7 (less than 1%). Thus rabbit cultured gastric cells were considered to be mainly comosed of mucous neck cells. These cells produced prostaglandin (PG) E2 and PGI2. Quantitatively cultured cells synthesized 1.475 +/- 0.039 ng/mg protein/hour of PGE2 and 0.244 +/- 0.042 pg/mg protein/hour of PGI2. This relatively simple and convenient technique provides a useful model for the study of cellular functions of gastric mucosa.
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PMID:A monolayer culture of gastric mucous cells from adult rabbits. 210 63

Enzyme treatment and mechanical tearing were used to separate syncytiotrophoblast from human placentae in this study. The normal fresh placentae were digested in a collagenase solution and then forced through a stainless steel mesh (mesh no. 60 = 0.301 mm). Smears of syncytiotrophoblast suspensions were stained with Wright's as well as PAS-hemotoxylin. It has given an isolation of 90-95% pure syncytiotrophoblast as obtained by our technique. The viability of the syncytiotrophoblast in the culture at onset and at harvesting was over 90%. The supernatants from short-term cultures of pure syncytiotrophoblast suppressed remarkably the maternal and fetal lymphocyte transformation to phytohemagglutinin and the one-way mixed lymphocyte culture. This effect is not antigen-specific, non-MHC restricted, and not due to non-specific toxic effects of dying cells. Our preliminary results, similar to that reported in the literatures indicate that the direct suppression by syncytiotrophoblasts and their products might play an important role in the protection of the fetus from rejection by the maternal immune system.
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PMID:[The immunosuppressive activity of human syncytiotrophoblast]. 263 60

Epithelial cells of the rat's epididymal caput were cultivated according to own modification of the Kierszenbaum's method [1981]. The said modification consisted in developing primary cultures of the epithelial cells in the epididymal duct by making use of small tubular segments instead of deisolated cells of the whole epididymal duct wall. Such small segments of the tubules were procured by resorting to mechanical isolation and a 4-grade enzymatic isolation with trypsin and collagenase, whereupon the produced suspension of cells and tubules was filtered through a grid, the meshes of which being 40 X 50 microns in diameter. The cultures were made up exclusively of the tubular segments that had remained on the grid. The utilized technique of isolation gets rid of tubules from the external layer of muscle cells and fibroblasts as well as spermatozoa still prior to the inception of the culture, and provides the possibility to obtain a pure population of epithelial cells. The latter cells have the capacity to migrate from tubular fragments, and to form monolayer cultures. In the conducted cultures the epithelial cells commence secreting PAS-positive substance which was evidenced by means of histochemical and microscope-electron examinations.
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PMID:Modified procedure for isolation of epithelial cells of rat epididymal caput. 280 90

A procedure for the isolation of epithelial cells from rat and human large bowel is described; the minced tissue was carefully washed with saline and incubated for 45 min in a collagenase-jaluronidase solution; the dispersion of the epithelial cells was achieved by a subsequent treatment with the calcium chelator EDTA. The isolated cells were characterized by cytological and histochemical (PAS, alkaline phosphatase, N-acetyl-D-glucosaminidase) procedures; viability index was assessed by the trypan blue exclusion test; the ability to grow in culture on both liquid and semisolid media was also tested. This method can be successfully applied either to normal or neoplastic colonic mucosa, the resulting cell suspension being suitable for further characterization.
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PMID:[Isolation and characterization of epithelial cells of colon mucosa: preliminary results]. 629 58

The snake venom of Echis coloratus was found to abolish the hemagglutinating activity, hemolytic activity and in vivo infectivity of Sendai virus. The active factor (Echinhibin-1) was purified by gel filtration on Sephadex G-50, followed by chromatography on DEAE-Sepharose and CM-Sepharose. Echinhibin-1 is a protease with a molecular weight of about 25 kDa, an isoelectric point of 7 and is stained by PAS, indicating that it is a glycoprotein. It showed a strong azocollase activity that was stable up to 68 degrees C and at pH values of 4.5-10.5. Ten micrograms/ml were sufficient to abolish the hemolytic effect of the virus on human erythrocytes when incubation was at 37 degrees C for 2 h, while 20 micrograms/ml abolished the hemagglutinating activity. Addition of Echinhibin-1 after the adsorption of Sendai virions onto washed erythrocytes at 4 degrees C did not inhibit the subsequently hemolytic activity at 37 degrees C, indicating that Echinhibin-1 interferes with virus adsorption to the cells. Of various protease inhibitors, only Na2 EDTA and o-phenanthroline inhibited the antiviral activity of the purified factor, indicating that it is a metalloproteinase. In vivo, mice inoculated intranasally with the virus pretreated with Echinhibin-1 developed well and gained weight, whereas untreated virus-infected mice lost weight and died within 1 week. Intravenous administrations of the purified factor up to 80 micrograms/mouse produced no signs of toxicity and subcutaneous injections caused no hemorrhagic activity, while the whole venom is very hemorrhagic with an LD50 of 250 micrograms/kg for mice.
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PMID:Echinhibin-1--an inhibitor of Sendai virus isolated from the venom of the snake Echis coloratus. 814 82

The enzyme digestion technique using collagenase is used in most studies that describe hepatocyte isolation, including those in which hepatocytes are isolated for transplantation. The use of collagenase, however, has several drawbacks. We describe the use of a highly concentrated ethylenediaminetetraacetate solution for isolation of hepatocytes followed by purification using a Percoll gradient in the rabbit model. Isolated hepatocytes were then preserved at 4 degrees C for up to three days in either University of Wisconsin solution or Dulbecco's modified eagle's medium. Morphological studies of hepatocytes at 24 hr and 72 hr in either medium were performed using Papanicolaou and PAS stains of cytopreparations for the presence of glycogen. Similarly, functional studies of the preserved hepatocytes included LDH release, total tissue water content, and amount of 99m-technetium mebrofenin uptake. The use of EDTA perfusion for hepatocyte isolation was highly reproducible in this model. The cell yield was comparable to that achieved previously using collagenase. The morphologic studies demonstrated pure hepatocytes with well-preserved architecture when preserved for up to three days in UW solution. Functional studies showed a statistically significant lower LDH release and total tissue water content and a higher technetium-99m mebrofenin uptake for hepatocytes preserved in UW solution. We conclude that a pure and viable hepatocyte suspension can be obtained from rabbit livers using concentrated EDTA solutions. These hepatocytes can be well preserved at 4 degrees C for up to 72 hr in UW solution, based on morphologic and functional criteria.
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PMID:The morphology and function of rabbit hepatocytes isolated using ethylenediaminetetraacetate. 843 84

Heterotopic hepatocyte transplantation (HcTx) in polymeric matrices may become an alternative to liver transplantation for metabolic disorders. Hepatotrophic stimulation by means of a portocaval shunt operation is an established, but invasive, procedure used to optimize hepatocyte engraftment in matrices. We evaluated hepatocyte and pancreatic islet cotransplantation (ICT) as an alternative noninvasive approach to hepatotrophic stimulation. Lewis rats served as donors and recipients. Hepatocytes and islets were isolated using collagenase digestion and seeded into polyvinylalcohol matrices. HcTx and ICT were compared with HcTx plus portocaval shunt and HcTx without stimulation. Matrices were investigated at 1, 3, and 6 months after implantation: the test methods applied were trichrome staining, PAS, immunohistochemistry for insulin, glucagon and incorporated BrdU, and in situ hybridization for albumin RNA. Hepatocytes expressed albumin RNA and formed conglomerates without atypias in all animals. ICT and portocaval shunting increased the number of hepatocytes and BrdU uptake. Alpha cells migrated into the islet-surrounding hepatocytes, whereas beta cells remained immobile. It is concluded that ICT and portocaval shunting supported engraftment of hepatocytes in polymeric matrices equally well. ICT did not interfere with recipient glucose metabolism and did not induce hyperproliferative premalignant foci within the transplanted hepatocytes. The technique is an attractive approach to hepatotrophic stimulation of bioartificial liver equivalents.
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PMID:Interaction of hepatocytes and pancreatic islets cotransplanted in polymeric matrices. 1059 11

The implantation of fragmented rat intestinal epithelium into the omentum of syngeneic animals results in the formation of a cyst containing neointestine. The purpose of our project was to study the evolution of this neointestine-containing cyst over time. Harvested jejunum and ileum of neonatal DA rats (6 to 8 days old) was digested with collagenase type XI and dispase at room temperature. The resulting organoid units, containing clusters of intestinal epithelium with stem cells were seeded onto a polyglactin polymer mesh (100000 units per mesh). The absorbable mesh was implanted in the omentum or peritoneal wall of an adult syngeneic animal. Animals were sacrificed at weekly intervals to harvest the neointestinal cysts. The lumen of the neointestine cysts was full of mucous while the wall of the cyst was covered by intestinal mucosa. H&E staining of the cyst demonstrated the morphology of intestinal epithelium; PAS staining identified goblet cells. The size of the cyst was maximal between 4 and 8 weeks postimplantation tending to regress thereafter. Neointestinal cysts are a consistent finding after implantation of intestinal epithelium organoids into the omentum or peritoneal wall in the rat model. The cysts reach a maximal size at 4 to 8 weeks postimplantation, tending to regress thereafter.
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PMID:Study of the development and evolution of neointestine in a rat model. 1505 Jan 64


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