Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

In untreated patients with inoperable lung cancer, serum levels of alpha1-antitrypsin were found significantly increased in comparison to patients with non malignant diseases of the lung, alpha2-macroglobulin levels were unchanged in both groups of patients. There was also no difference in alpha2-macroglobulins in cancer patients reacting with DNCB and in non-reactors. Thus alpha2-macroglobulin levels do not seem to correlate with the immunestatus of cancer patients. Proteinase inhibitors are involved in a variety of biological processes including blood, clotting, digestion, and sperm capacitation. alpha1-antitrypsin, a alpha-globulin with a molecular weight of about 60,000 has been found to be decreased in patients' serum under several pathological conditions. A clear correlation exists between alpha1-antitrypsin deficiency and hereditary pulmonary emphysema (1, 2), respiratory distress syndrome (3), and juvenile cirrhoses of the liver (4). Elevated serum levels of alpha1-antitrypsin have also been found in some cancer cases. Thirty years ago a cancer test was developed on the basis of differences in the antiproteolytic activity in cancer patients' sera and in patients with other non-neoplastic diseases (5, 6). Several authors have tried to confirm these early data regarding specifity and sensitivity with respect to a screening test for cancer (7, 8). Methods of these authors were based mainly on enzyme substrate inhibition assays by addition of the patients' sera. Recently a commercially available test, based on immune-precipitation according to Mancini (9), has been developed (Behring-Werke, Partigen). By using this standardized method for determinating alpha1-antitrypsin, Harris et al. have recently demonstrated that patients with inoperable lung cancer have significantly elevated levels of this antiprotease in their sera (10), in comparison to patients with non malignant diseases of the lung. alpha2-macroglobulin is a serum protein with a molecular weight of 800,000 and with known antiprotease activity and can therefore bind trypsin, plasmin, elastase, and collagenase and it is known that alpha2-macroglobulin decreases with increasing of age. Changes of alpha-macroglobulin have also been observed in several pathological conditions (11). James et al. 4ave found decreases in serum of myeloma patients (12). An association between the development and function of lymphocytes and alpha2-macroglobulin has been suggested by several authors (13, 14). This alpha2-globulin has also been demonstrated on the surface of peripheral blood lymphocytes (15) and there is evidence that it is synthesized by lymphocytes (16). The purpose of the present study was to determine serum alpha1-antitrypsin levels in patients with inoperable lung cancer and to determine whether there is also an inverse correlation to alpha2-macroglobulin. It was further attempted to correlate alpha2-macroglobulin with general immunological parameters, as it is known that patients with lung cancer show a decreased general immune-reactivity (17).
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PMID:Serum levels of alpha1-antitrypsin and alpha2-macroglobulin in lung cancer. 6 86

1. Explants of dog gingiva, maintained in culture for 9 days in the absence of serum, released a collagenase (EC 3.4.24.3) into the medium. The yield of active enzyme reached a maximum after 5-8 days with concomitant release of collagen degradation products from the explants. 2. The enzyme attacked undenatured collagen in solution at 25 degrees C resulting in a 58% loss of specific viscosity and producing the two characteristic products TCA(3/4) and TCB(1/4). Electron microscopy of segment-long-spacing crystallites of these reaction products showed the cleavage locus of the collagen molecule at interband 40. 3. Optimal enzyme activity was observed over the pH range 7.5-8.5 and a molecular weight of approximately 35,000 was derived from gel filtration studies. EDTA, 1,10-phenanthroline, cysteine and dithiothreitol all inhibited collagenase activity. Proteoglycan derived from porcine and human cartilage did not inhibit the enzyme. 4. The enzyme was inhibited by the dog serum proteins alpha2-macroglobulin and a smaller component of molecular weight approximately 40,000. This small component was purified by column chromatography utilising Sephadex G-200, DEAE A-50, and G-100 (superfine grade). Agarose electrophoresis of the purified component showed it to represent a beta-serum protein. alpha1-Antitrypsin did not inhibit the enzyme. 5. The physiological importance of the natural serum inhibitors and gingival collagenase are discussed in relation to latent enzyme and periodontal disease.
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PMID:Characterization and serum inhibition of neutral collagenase from cultured dog gingival tissue. 7 61

Cells obtained by continuous perfusion with collagenase maintained their ultrastructure and their capacity for protein synthesis in contrast to mechanically isolated rat liver cells. Albumin and angiotensinogen (renin substrate) are synthesized and secreted and the synthesis of both proteins is stimulated by addition of hydrocortisone. As cell suspensions allow the simultaneous investigation of several samples under well defined conditions they can serve as an excellent model for the study of regulatory mechanisms of serum protein synthesis.
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PMID:[Blood protein synthesis in isolated liver cells]. 19 70

The attachment of rat hepatocytes to polystyrene-adsorbed serum protein is relatively insensitive to inhibitors such as dextran sulphate, cycloheximide, colchicine and cytochalasin B, and enzymes like trypsin and neuraminidase, but it is strongly dependent on divalent cations. Mg2+ supports attachment better than Ca2+, but a combination of both is required for maximal attachment. The attachment is very temperature-sensitive, with a biphasic Arrhenius plot indicating an activation energy of 123 kJ/mol above 34 degrees C and 374 kJ/mol below 34 degrees C. The adsorbed attachment-promoting serum factor is inactivated by trypsin, or by Ca2+-dependent proteases which contaminate commercial preparations of collagenase. The adsorbed factor is resistant to treatment with glutaraldehyde, neuraminidase and heating to 90 degrees C, whereas the same factor in the unadsorbed state (in serum) is destroyed by heating to 70 degrees C. The factor in serum is unable to compete with the adsorbed factor for cell binding, hence it would appear that adsorption to polystyrene induces the active, heat-resistant conformation of the factor.
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PMID:Effect of temperature and divalent cations on the substratum attachment of rat hepatocytes in vitro. 74 33

A sensitive bioassay for serum LH and hCG has been developed by utilization of the testosterone response of collagenase-dispersed rat Leydig cells to gonadotropic stimulation in vitro. Testosterone production by dispersed interstitial cells is stimulated by human, ovine, bovine, porcine, rat and rabbit LH, and by hCG and pregnant mare serum gonadotropin. The rat testis interstitial cell assay gives parallel dose-response curves for all steroidogenic gonadotropins tested, and thus permits cross-species comparison of the intrinsic biological activities of native and modified gonadotropins. The sensitivity of the rat interstitial cell bioassay is equal to or higher than that of radioimmunoassay, with detection limits of 50 muU for hMG and 20 muU for hCG. The optimum conditions for bioassay of serum gonadotropins were provided by incubation of dispersed interstitial cells in the presence of 1-methyl 3-isobutyl xanthine with the addition of gonadotropin-free serum or 5% BSA to ensure a constant proportion of serum protein in all assay samples and standards. Assays performed under these conditions gave parallel dose-response curves and identical maximum responses to both standards and serum samples containing endogenous LH or hCG. All responses to human gonadotropin standards and serum samples in the bioassay were abolished by incubation in the presence of antisera to LH or hCG. This sensitive and specific method permits bioassay of basal levels of LH in male and female serum, and of the higher gonadotropin levels in postmenopausal and pregnant subjects after appropriate dilution of the serum samples. For normal men and women, serum samples of 25-100 mul are employed, while volumes of 1-20 mul are adequate for assay of LH in postmenopausal or hypogonadal subjects. Serum LH values in hypopituitary and oral contraceptive-treated subjects were usually undetectable, while LH levels in normal subjects were always measurable with good precision. The within-assay coefficient of variation for measurement of a normal male plasma pool (30 mU/ml) was +/- 10%, and the between-assay variation was +/- 15%. The precision of the assay (lambda) was 0.035 +/- 0.015 (n = 72). In 42 normal females, the bio: immuno (B:I) ratio for serum LH was 1.20 +/- 0.40 (SD), and no consistent change in ratio was observed throughout the menstrual cycle. By contrast, significantly higher B:I ratios were observed in normal males (2.5 +/- 0.4), postmenopausal females (2.6 +/- 0.6) and patients with Turner's syndrome (2.6 +/- 0.6). These findings suggest that the LH circulating in normal female plasma is similar in biological and immunological activity to hMG, whereas the LH present in normal male plasma and in states of increased gonadotropin secretion has a relatively higher biological activity. The rat interstitial cell bioassay provides for the first time a practical and precise assay for measurement of the biologically active LH levels in serum of normal biologically active LH levels in serum of normal human subjects.
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PMID:In vitro bioassay of LH in human serum: the rat interstitial cell testosterone (RICT) assay. 127 May 85

Matrix metalloproteinases are an important group of zinc enzymes responsible for degradation of the extracellular matrix components such as collagen and proteoglycans in normal embryogenesis and remodeling and in many disease processes such as arthritis, cancer, periodontitis, and osteoporosis. A matrixin family is defined, comprising at least seven members that range in size from Mr 28,000 to 92,000 and are related in gene sequence to collagenase. All family members are secreted as zymogens that lose peptides of about 10,000 daltons upon activation. Latency is due to a conserved cysteine that binds to zinc at the active center. Latency is overcome by physical (chaotropic agents), chemical (HOCl, mercurials), and enzymatic (trypsin, plasmin) treatments that separate the cysteine residue from the zinc. Expression of the metalloproteinases is switched on by a variety of agents acting through regulatory elements of the gene, particularly the AP-1 binding site. A family of protein inhibitors of Mr 28,500 or less binds strongly and stoichiometrically in noncovalent fashion to inhibit members of the family. The serum protein alpha 2-macroglobulin and relatives are also strongly inhibitory.
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PMID:Matrix metalloproteinases and their inhibitors in connective tissue remodeling. 185 Jul 5

The periodontium, especially the periodontal ligament and alveolar bone, are tissues constantly subjected to physical stress such as occlusion and mastication. This study was designed to explore the effect of the pulsed electromagnetic fields (PEMF) on the cell attachment and the spread of human periodontal ligament fibroblasts (HPLF) and rat osteoblasts (ROB). PEMF are categorized as one type of mechanical stress. HPLF were obtained by the explantation method described by Saito et al. They were then subcultured in Dulbecco's modified Eagle's medium (D-MEM) and supplemented with 2 mg/ml dialyzed fetal calf serum protein (FCSP), 50 micrograms/ml ascorbic acid and penicillin/streptomycin after trypsinization. ROB were isolated from a two-day-old rat calvaria by the sequential bacterial collagenase digestion method described by Dziak and Brand and were subcultured in D-MEM supplemented with FCSP, ascorbic acid and penicillin/streptomycin. After the confluent HPLF were cultured with serum-free MCDB 107 medium, the quiescent HPLF were exposed with or without PEMF for 24 hr. This was followed by the collection of the control conditioned medium (C-CM) and PEMF exposed conditioned medium (PEMF-CM). The cell attachment assay was performed so that the hydrophobic 24 multiwells were coated with the whole conditioned medium or fractionated conditioned medium by a PO-60K column. After coating, heat inactivated BSA blocked nonspecific sites for cell adhesion, and 3H-TdR labeled HPLF or ROB were cultured on the precoated wells. The activity of cell attachment and spreading was determined by the radioactivity of 3H-TdR using a scintillation counter. The characters of cell attachment factors derived from HPLF were hydrophobic, heat labile and proteolytic enzyme digestible. In addition, the fractionated PEMF-CM enhanced the spreading activity of ROB. PEMF induced the 10 KDa which can enhance the HPLF and ROB spreading. Therefore, the cell attachment and spreading factors secreted by HPLF exposed with PEMF may regulate HPLF and also ROB.
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PMID:Biochemical study of human periodontal ligament: preparation of cell attachment materials induced by pulsed electromagnetic fields. 213 6

Embryospecific serum protein alpha-fetoprotein (AFP) is known to be synthesized in the adult liver only during regeneration and development of hepatocellular carcinomas. It was shown that collagenase digestion of hepatic tissue followed by monolayer cell cultivation was a powerful inducer of AFP synthesis, more potent than the liver regeneration in vivo. The treatment of hepatocytes in culture with 50-100 micrograms/ml of dextran sulphate caused a remarkable inhibition of cell proliferation, formation of cord-like multicellular structures and reduction of AFP synthesis. Mouse liver regeneration after CCL4 poisoning was accompanied by a 1000-fold increase in blood AFP levels. Blood AFP levels and the content of AFP-positive cells in the liver tissue were maximum on the 3rd-4th day after poisoning. Injections of 50 micrograms of dextran sulphate per g body weight 3-5 h after poisoning and 24 and 48 h later caused nearly tenfold reduction in AFP blood level and a decrease in the content of AFP-positive cells in the liver on the 3rd day of regeneration.
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PMID:[Inhibition of alpha-fetoprotein synthesis in hepatocytes of adult mice by dextran sulfate in vivo and in vitro]. 243 82

Hepatocytes were isolated from human fetal liver in order to analyze the direct effects of growth factors and hormones on human hepatocyte proliferation and function. Mechanical fragmentation and then dissociation of fetal liver tissue with a collagenase/dispase mixture resulted in high yield and viability of hepatocytes. Hepatocytes were selected in arginine-free, ornithine-supplemented medium and defined by morphology, albumin production and ornithine uptake into cellular protein. A screen of over twenty growth factors, hormones, mitogenic agents and crude organ and cell extracts for effect on the stimulation of hepatocyte growth revealed that EGF, insulin, dexamethasone, and factors concentrated in bovine neural extract and hepatoma cell-conditioned medium supported attachment, maintenance and growth of hepatocytes on a collagen-coated substratum. The population of cells selected and defined as differentiated hepatocytes had a proliferative potential of about 4 cumulative population doublings. EGF and insulin synergistically stimulated DNA synthesis in the absence of other hormones and growth factors. Although neural extracts enhanced hepatocyte number, no effect on DNA synthesis of neural extracts or purified heparin-binding growth factors from neural extracts could be demonstrated in the absence or presence of defined hormones, hepatoma-conditioned medium or serum. Hepatoma cell-conditioned medium had the largest impact on both hepatocyte cell number and DNA synthesis under all conditions. Dialyzed serum protein (1 mg/ml) at 10 times higher protein concentration had a similar effect to hepatoma cell-conditioned medium (100 micrograms/ml). The results suggest that hepatoma cell conditioned medium may be a concentrated and less complicated source than serum for purification and characterization of additional normal hepatocyte growth factors.
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PMID:Direct analysis of growth factor requirements for isolated human fetal hepatocytes. 244 74

Relation between processes of proliferation and synthesis of the embryonal serum protein alpha-fetoprotein (AFP), the influence on these processes of polyelectrolyte dextran sulfate (DS) and dimethyl-sulfoxide (DMSO) has been studied in the monolayer culture of mouse hepatocytes. In control cultures the correlations between the time of appearance and the level of DNA and AFP synthesis were observed. DS and DMSO were found to inhibit both processes. Cell proliferation could be reestablished by addition of epidermal growth factor. In case of the influence of DMSO, it wasn't followed by the induction of AFP synthesis. This the processes of DNA and AFP synthesis in monolayer cultures of mouse hepatocytes can be separated. The elongated incubation of hepatocytes with collagenase during their obtaining, abolished the effects of DS. This shows that surface components of hepatocytes, lost upon enzyme degradation, may be involved in the mechanism of DS effect.
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PMID:[Synthesis of DNA and alpha-fetoprotein in the monolayer culture of mouse hepatocytes]. 245 78


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