Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.16.3.1 (ceruloplasmin)
 5,074 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vitro binding, internalization and release of the plasma protein ceruloplasmin was investigated using primary cultures of human placental trophoblast cells. Binding of 125I-labelled ceruloplasmin at 4 degrees C reached equilibrium by 5-6 h; binding was linear throughout all concentrations tested (1 nM-3.3 microM). Addition of greater than 5-10 microM unlabelled ceruloplasmin or a variety of other proteins (albumin, transferrin, IgG) were equally effective in displacing bound ceruloplasmin in a concentration-dependent manner. When cells were incubated at 37 degrees C, the majority of surface-bound 125I-labelled ceruloplasmin was released directly to the extracellular medium. Trypsin-resistant radioactivity increased to 18 per cent of initially bound ceruloplasmin within 1 min, declining to 5 per cent by 2 h. The acquisition of trypsin-resistant radioactivity was unaffected by the addition of a variety of metabolic inhibitors and no evidence of intracellular degradation of ceruloplasmin was found. In summary, our results suggest that the majority of ceruloplasmin binding to trophoblast cells is nonspecific, of low affinity, and easily dissociable at 4 degrees C. Only a small amount of ceruloplasmin appeared to be internalized, by an as yet unknown mechanism.
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PMID:Interaction of 125I-labelled ceruloplasmin with human trophoblast cells in vitro. 229 Aug 3

Monitoring of plasma proteinases, proteinase inhibitors and other selective plasma proteins was evaluated in patients undergoing Y-graft aortofemoral bypass operation. Fast-reacting acute-phase proteins (C-reactive protein, antichymotrypsin, alpha 1-acid glycoprotein) and slow-reacting proteins (haptoglobin, alpha 1-antitrypsin) increased significantly 48-120 h after operation. By contrast, no significant increase was found between plasma ceruloplasmin levels before clamping and after declamping. Activity and concentration of alpha 2-macroglobulin decreased postoperatively and remained significantly lowered throughout the observation period. Plasma levels of granulocyte elastase were elevated significantly 1 h after declamping, whereas trypsin-binding capacity decreased immediately after the release of the clamp. Aprotinin pretreatment caused higher trypsin-binding capacity of the plasma, significantly lower 'unspecific' proteolytic (azocasein-hydrolyzing) activity and significantly lower non-TCA precipitable low molecular weight plasma protein concentration. Our results confirm the data of several authors that monitoring of plasma proteinases, proteinase inhibitors and other selective plasma proteins may be helpful in evaluating surgical patients postoperatively.
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PMID:Plasma proteinases, proteinase inhibitors and other selective plasma proteins following aortofemoral bypass operation. 242 35

Synovial fluids of patients suffering from rheumatoid arthritis and osteoarthritis with effusions of the knees were examined. Different parameters were evaluated out of the synovial fluid (immunglobulins, Complement-1Q,-3,-4, haptoglobins, alpha-1-anti-trypsin, alpha-2-macroglobulin, transferrin, ceruloplasmin, rheumatoid factors, total count of cells, and ragocytes) and out of the plasma (blood sedimentation rate). The proteins were analysed by a nephelometricturbidimetric automatic centrifugal analyser. All parameters have been tested by valuable statistical methods and correlated to each other. The results worked out proved the reliability of the used test kits and apparative systems. Correlations within groups of parameters according to their formations (intra-and/or extraarticular) could not have been worked out in a way as it may be supposed. In contrast some parameters themselves are statistically different comparing rheumatoid arthritis and osteoarthritis. In general the results are on a higher level in the rheumatoid arthritis group. Using all parameters mentioned above the statistical differential diagnostic level is based on about 94%. If only blood sedimentation rate, total cell count and ragocytes are evaluated the level is based on 68%.
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PMID:[Differential diagnostic value of nephelometrically determined protein fractions in the synovial fluid]. 244 12

The sensitive and reliable dinitrophenyl (DNP) hapten sandwich staining (DHSS) procedure (B. Jasani et al., Virchows Arch (Pathol. Anat.), 406 (1985) 441-448) was used to study the distribution of immunoperoxidase staining seen with antibodies to seven protein markers in post-mortem heart tissue. This was obtained from 12 cases with macroscopic myocardial infarction and 17 cases without myocardial infarction (10 with and 7 without significant coronary artery atherosclerosis). The immunostaining patterns were compared with the appearances seen in adjacent sections stained by the routine haematoxylin and eosin (H & E) and phosphotungstic acid haematoxylin (PTAH) methods and a method previously recommended for the detection of early myocardial infarction, the haematoxylin basic fuchsin picric acid (HBFP) stain. Loss of immunostaining with an antibody to myoglobin was found to be a reliable and more objective marker of both early and established myocardial infarction compared with the histological stains. Antibodies to myosin, caeruloplasmin, C-reactive protein and pre-albumin gave similar but less reliable results, whilst those to complement factor C3b and alpha-1 anti-trypsin gave the least reliable results for early myocardial ischaemic/hypoxic damage. The immunocytochemical results are considered sufficiently encouraging to extend the work to a large number of sudden death cases in order to establish a new, more reliable approach to the detection of histologically latent ischaemic/hypoxic damage in the myocardium.
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PMID:Immunocytochemical diagnosis of early myocardial ischaemic/hypoxic damage. 264 26

The structural fragments of the human ceruloplasmin (CP) molecule and of erythrocyte receptors which provide for the specific interaction of CP with erythrocytes were identified, and their properties were investigated. The interaction of CP with erythrocytes, both intact and treated with neuroaminidase and proteolytic enzymes (trypsin, chymotrypsin, papaine, pronase E) is described. Experiments with CP reception were performed at 4 degrees C, using [125I]CP and [125I]asialo-CP. The parameters of binding were determined in Scatchard plots. It was demonstrated that the specific binding of CP to erythrocyte receptors is determined by its interaction with two structural sites of the carbohydrate moiety of the CP molecule, i.e., the terminal residues of sialic acids and a site, (formula; see text) located at a large distance from the chain terminus.
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PMID:[Ceruloplasmin receptor on human erythrocytes]. 284 18

Interleukin 6 (IL6) is the new definition of a group of cytokines previously named according to their biological activity, e.g. B cell stimulatory factor 2 (BSF-2), hybridoma plasmocytoma-growth factor (HGF), interferon-beta 2 (IFN-beta 2), hepatocyte stimulating factor (HSF). It has recently been suggested that IL6 may represent the major mediator of acute-phase protein response whereas IL1 beta and TNF-alpha could play a minor role. We compared the effect of the three cytokines on hepatic protein synthesis by performing in vitro as well as in vivo experiments. Human hepatoma cells (PLC/PRF5) were exposed to each cytokine separately for 20 h, and the effect was then studied at the protein and RNA level. All three cytokines reduced albumin and increased C3 and ceruloplasmin biosynthesis. The cytokines induced the same effect at the RNA level indicating that the modulation was pretranslational. The effect of the cytokines was specific since actin gene expression was not changed; furthermore the effect was blocked by specific antibodies against the cytokines. The effect of the single cytokines was dose and time dependent, and quantitatively comparable. None of the cytokines was able to alter alpha 1-anti-trypsin synthesis. In vivo experiments with mice showed that IL1 beta and TNF-alpha both induce serum amyloid A (SAA) mRNA in the mouse liver and increase factor B (Bf) gene expression. Human recombinant IL6 induced SAA gene expression and it also had a weak positive effect on Bf gene expression after i.p. injection. These data demonstrate that the three cytokines studied are quantitatively and qualitatively comparable, and that all three are probably involved in acute-phase protein response.
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PMID:Interleukin 6, the third mediator of acute-phase reaction, modulates hepatic protein synthesis in human and mouse. Comparison with interleukin 1 beta and tumor necrosis factor-alpha. 313 37

Oxidant injury and release of proteolytic enzymes in prematures with respiratory distress syndrome (RDS), who are treated with ventilators and oxygen, have been postulated as possible causes of bronchopulmonary dysplasia (BPD). The premature may be at particular risk due to low levels of antiproteases, such as alpha-1-proteinase inhibitor (alpha 1PI), and antioxidants, such as ceruloplasmin (CER). Both alpha 1PI and CER deficiencies have been correlated with the severity of RDS. We studied serial alpha 1PI activity as measured by trypsin inhibitory capacity (TIC) and CER in the serum 27 prematures who required ventilator therapy for RDS. Serum TIC values for day 1 were significantly lower (0.34 vs. 0.92 mg inhibited/ml of sample) in the 13 patients who developed BPD compared to the 14 who did not. No significant differences were seen on succeeding days. No significant differences in CER were seen, although both groups had levels 33-50% of adult normals (11.3 vs 9.3 mg/dl). Other significant variables included birthweight (p less than 0.005), severity of RDS (p less than 0.03), and gestational age (p less than 0.03). One way analysis of variances demonstrated day 1 TIC to be the most significant variable (p less than 0.0001), followed by weight (p less than 0.007), severity RDS (p less than 0.04), and gestational age (p less than 0.03). CER levels were not a significant variable. A formula utilizing unstandardized canonical discriminant function including day 1 TIC, birthweight, severity of RDS, and gestational age was 100% sensitive and 85% specific in the prediction of BPD for the original study group. In an additional 25 consecutive admissions with severe RDS of whom 18 survived, the formula was 100% sensitive (6/6) and 75% specific (9/12).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serial trypsin inhibitory capacity and ceruloplasmin levels in prematures at risk for bronchopulmonary dysplasia. 349 55

Patients with rheumatoid arthritis have altered protein patterns in their serum and synovial fluid which influences the antioxidant activity of these fluids. Rheumatoid serum has a higher antioxidant activity than control serum when ferrous and ferric ions stimulate membrane damage. The raised levels of caeruloplasmin and the lower iron saturation of transferrin contribute to these differences. When membrane damage is stimulated by a copper salt, rheumatoid serum does not show an increased antioxidant protection and has probably a lower protective activity than control serum. Attempts to damage caeruloplasmin and transferrin with oxygen radicals were unsuccessful. However, prolonged incubations with trypsin reduced the iron-binding capacity of transferrin and decreased the ferroxidase and antioxidant properties of caeruloplasmin. Copper was released from caeruloplasmin under these conditions.
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PMID:Antioxidant properties of the proteins caeruloplasmin, albumin and transferrin. A study of their activity in serum and synovial fluid from patients with rheumatoid arthritis. 394 55

Membrane fragments from aortic and heart tissues of immature chicks were observed to bind highly purified, 125I-labeled chick ceruloplasmin. The binding reaction exhibited a linear Scatchard plot for both tissues and showed for each an apparent dissociation constant (Kd) of about 10(-8) M. On the basis of Scatchard analyses, aorta contained 1.5 pmol of receptors/mg of membrane protein, whereas receptors in the membranes from heart tissue were at least 5 times more dense. The binding of chick ceruloplasmin to aorta membranes was trypsin sensitive and neuraminidase insensitive, and showed both saturation and reversibility. Various sialoglycoproteins in 500 molar excess had very little effect on the binding. The asialo derivatives of these proteins likewise did not inhibit the binding. Human ceruloplasmin was found to bind very weakly to the chick membranes. Asialo chick ceruloplasmin bound with the same efficacy as native chick ceruloplasmin. Heat-denatured chick ceruloplasmin, however, was very ineffectual in displacing native 125I-ceruloplasmin from the membranes. These studies provide the first evidence for a homologous membrane receptor for native ceruloplasmin in the plasma membranes of animal cells.
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PMID:Specific receptor for ceruloplasmin in membrane fragments from aortic and heart tissues. 632 Aug 63

Assays of serum benzylamine oxidase (BzAO) have led some workers to postulate a relationship between elevated BzAO activity and diseases characterized by proliferating connective tissue. The present study was designed to determine whether BzAO activity of a cellular tissue is also affected. BzAO was assayed in homogenates of normal and atherosclerotic human aortae. Characterization done in normal aortae showed that BzAO is not a classical monoamine, diamine, polyamine, or lysyl oxidase, nor is it a ceruloplasmin. The enzyme is heat stable at 60 degrees C and is associated primarily with the microsomal fraction on density centrifugation. Compared with phenylethylamines and indoleamines, benzylamine is the best substrate. BzAO is sensitive to inhibition by hydrazines and chymotrypsin but not trypsin, and is insensitive to Triton X-100 and sulfhydryl-group blockade. BzAO activity of atherosclerotic plaque (expressed per gram wet weight or per milligram protein) was decreased markedly compared to that in adjacent, nonplaque regions and in normal aortae. However, on a per milligram DNA basis, the BzAO activity of plaque did not differ from that of nonplaque tissue. We conclude that there is a decreased cell population density in plaque, a contention supported by kinetic analysis. Plaque BzAO showed a decreased Vmax with no change in the Km of benzylamine compared with nonplaque tissue. Thus, if a relationship exists between BzAO activity and proliferating connective tissue, it is not apparent at the level of the cellular enzyme in atherosclerotic aortae of man.
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PMID:Benzylamine oxidase in normal and atherosclerotic human aortae. 683 47


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