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)

The effects of various experimental conditions during the isolation of monkey islets by the collagenase method on the insulinogenic response of the isolated islets to glucose have been studied and compared with rat islets isolated under similar conditions. The monkey islets gave a normal response for at least 120 min. The results are compared with available studies on primate islets.
Diabetes 1979 Sep
PMID:Studies on insulin secreted by isolated islets of the monkey, Macaca radiata radiata. 11 84

The influence of the mode of preparation upon some of the characteristics of white adipose tissue plasma membranes and microsomes has been reported. Plasma membrane fractions prepared from mitochondrial pellet were shown to have higher specific activities of (Mg2+ + Na+ + K+)-ATPase than plasma membranes originating in crude microsomes. Isolation of fat cells by collagenase treatment was found to result in a decrease in specific activity of the plasma membrane enzymes; in plasma membranes prepared from isolated fat cells, the specific activity values obtained for (Mg2+ + Na+ +k+)-ATPase and 5'-nucleotidase were only 42% and 6.3% respectively of those obtained in plasma membranes prepared from whole adipose tissue. Purification of whole adipose tissue crude microsomes by hypotonic treatment caused extensive solubilization of the endoplasmic reticulum marker enzymes, NADH oxidase and NADPH cytochrome c reductase. The lability of endoplasmic reticulum marker enzymes, however, was found to be greatly diminished in the preparations from isolated fat cells. The possibility that NADH oxidase and NADPH cytochrome c reductase activities found in the plasma membranes are microsomal enzymes adsorbed by the plasma membranes is discussed. The peptide patterns as well as the NADH oxidase and NADPH cytochrome c reductase activity patterns of plasma membranes and purified microsomes were compared by means of sodium dodecyl sulfate or Triton X-100 polyacrylamide gel electrophoresis.
Biochim Biophys Acta 1975 Sep 16
PMID:Comparison of plasma membranes and endoplasmic reticulum fractions obtained from whole white adipose tissue and isolated adipocytes. 12 89

We have developed an enzymatic technique for isolating human intestinal mucosal lymphoid cells. This method was found to be superior to mechanical methods in regard to cell yield and survival. It is based on treating mucosa with serum-free solutions containing collagenase and deoxyribonuclease, followed by isolating the lymphoid cells through centrifugation steps involving fetal calf serum and ficoll-hypaque. Exposure of peripheral blood lymphocytes to the components of the enzymatic solution did not appreciably alter their uptake of tritiated thymidine in the presence or absence of mitogens. Application of the method to derive lymphoid cells from Crohn's disease, ulcerative colitis, and normal intestinal mucosa has shown that gut mucosal lymphocytes from inflammatory bowel disease (1) exceed the number of those from normal mucosa by a factor of 3 to 5; (2) show different degrees of tritiated thymidine uptake, spontaneously and in response to mitogens, depending upon the time they are harvested during the dissociation process; (3) are better stimulators than responders in the allogeneic mixed lymphocyte reaction; (4) generate suppressor cell activity comparable to that of peripheral blood lymphocytes; (5) cannot, in contrast to peripheral blood lymphocytes, generate antibody-dependent cell mediated cytotoxicity; and (6) produce an average of 5 times more IgM than equal numbers of peripheral blood lymphocytes.
Dig Dis Sci 1979 Sep
PMID:Gut mucosal lymphocytes in inflammatory bowel disease: isolation and preliminary functional characterization. 15 97

Lymphocytes infiltrating synovial membranes were characterized in eight patients with proliferative rheumatoid synovitis. Surface immunoglobulins were studied with use of immunofluorescence, and the C3 receptor was detected by adherence of red cells coated with antibody and complement - both are B-cell markers. Spontaneous rosette formation with sheep erythrocytes was used as a T-cell marker. To obtain viable lymphocytes in suspension, the villous synovium of five of these patients was digested with collagenase and deoxyribonuclease. Populations enriched in lymphocytes could be obtained by velocity sedimentation. Whereas only 9 to 35 per cent of lymphocytes bore surface immunoglobulins, the majority (70 to 85 per cent) formed sheep-erythrocyte rosettes. Cells bearing the C3 receptor constituted a distinct minority of synovial lymphocytes in frozen-tissue sections, and were found in follicle-like accumulations. These data indicate that the predominant infiltrating lymphocyte in proliferative rheumatoid synovitis is a T cell.
N Engl J Med 1975 Sep 11
PMID:Predominantly T-cell infiltrate in rheumatoid synovial membranes. 16 88

1. Enzymes that may contribute to liquefaction of the cornea in retinol-deficient animals and in man have been studied using rat cornea. The established technique of culturing tissue fragments and determining the activity of collagenase (EC 3-4-24-3) and other enzymes in the medium after different periods of culture was used. 2. A collagenolytic system was detected in the media from cultures of rat corneas. This system probably consists of at least two enzymes, a collagenase and a neutral proteinase. 3. Both proteolytic and specific collagenolytic activity were greater in media from retinol-deficient rat corneas. The hydroxyproline level increased in parallel with the increase in enzyme activity. 4. In the final stages of retinol deficiency the cornea is invaded by granulocytes and other cells of the blood and we suggest that destruction of cornea collagen may be due largely to the activity of the enzymes from these cells.
Br J Nutr 1975 Sep
PMID:Collagenase and other proteinases in the cornea of the retinol-deficient rat. 16 77

The ultrastructure of human umbilical cord vein endothelium in situ, after isolation by collagenase treatment, and in primary culture is described. The cultured cells formed a monolayer with typical "butt" and interdigitated junctions with specialized areas, and contained Weibel-Palade bodies, rod-shaped tubular organelles considered specific of endothelial cells. These morphological features were not present in cultures of human skin fibroblasts and fibroblast-like cells derived from umbilical cords. It is thus concluded that endothelial cells retain their characteristic fine structure in primary culture. Simple ultrastructural studies can thus be used to identify endothelial cells in culture.
Cell Tissue Res 1975 Sep 16
PMID:Ultrastructural identification of umbilical cord vein endothelium in situ and in culture. 16 99

Embryonic chick RNA was translated in a cell-free system derived from wheat germ. One of the products synthesized in vitro under the direction of this RNA could be identified as collagen on the basis of collagenase digestion experiments and sodium dodecylsulfate-acrylamide gel electrophoresis. By submitting the RNA to chromatography on oligo(dT)-cellulose, a 26-30-fold enrichment of the mRNA coding for collagen was achieved.
Hoppe Seylers Z Physiol Chem 1975 Sep
PMID:Stimulation of collagen synthesis in a cell-free system by mRNA from chick embryos. 17 Jan 82

A new method for the preparation of cell suspensions from human newborn kidneys is described. It involves the use of a mixture of trypsin-ethylenediaminetetraacetic acid and collagenase. The cell yields obtained after tissue dispersion by this method were significantly greater than those obtained after dispersion with either trypsin or ethylenediaminetetraacetic acid alone or in combination. When kidneys were removed 12 h or more postmortem from refrigerated cadavers, higher cell yields were obtained from renal tissue stored overnight at 4 to 6 C in CMRL ATM (Healy and Parker, 1966), as compared to cell yields obtained from kidneys processed immediately upon removal. This observation was confirmed by controlled experiments performed with rabbit kidneys.
J Clin Microbiol 1975 Sep
PMID:Dispersion and cultivation of renal cells after short-term storage of kidneys. 17 Mar 18

Latent collagenase, subject to activation by trypsin, was found in culture fluids of cells and tissues from several mammalian sources. The activation requires exposure to enzymatically active trypsin and cannot be achieved by inhibited or by heat-inactivated trypsin.
Scand J Dent Res 1975 Sep
PMID:Trypsin activation of latent collagenase from several mammalian sources. 17 Jun 66

The molecule of type I collagen from skin consists of two alpha1(I)-chains and one alpha2-chain. The sequence of the entire alpha1-chain comprising 1052 residues is summarily presented and discussed. Apart from the 279 residues of alpha1(I)-CB8 whose sequence has been established for rat skin collagen, all sequences have been determined for calf skin collagen. In order to facilitate sequence analysis, the alpha1-chain was cleaved into defined fragments by cyanogen bromide or hydroxylamine or limited collagenase digestion. Most of the sequence was established by automated stepwise Edman degradation. The alpha1-chain contains two basically different types of sequences: the triple helical region of 1011 amino acid residues in which every third position is occupied by glycine and the N- and C-terminal regions not displaying this type of regularity. Both of these non-triple helical regions carry oxidizable lysine or hydroxylysine residues as functional sites for the intermolecular crosslink formation. Implications of the amino acid sequence for the stability of the triple helix and the fibril as well as for formation of crosslinks are discussed. Evaluation of the sequence in connection with electron microscopical investigations yielded the parameters of the axial arrangement of the molecules within the fibrils. Axial stagger of the molecules by a distance D = 670 angstrom = 233 amino acid residues results in maximal interaction of polar sequence regions of adjacent molecules and similarly of regions of hydrophobic residues. Ordered aggregation of molecules into fibrils is, therefore, regulated by electrostatic and electrophobic forces. Possible loci of intermolecular crosslinks between the alpha1-chains of adjacent molecules may be deduced from the dimensions of the axial aggregation of molecules.
Mol Cell Biochem 1975 Sep 30
PMID:Information contained in the amino acid sequence of the alpha1(I)-chain of collagen and its consequences upon the formation of the triple helix, of fibrils and crosslinks. 17 54


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