Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antiprotozoal drug pentamidine can be toxic to islet cells in vivo and in vitro. Rat islets were exposed to pentamidine (mesylate and isethionate salts) and six other structurally related diamidines. The beta-cell response to arginine + theophylline was suppressed by pentamidine (10(-2) mmol/l) while the glucagon and somatostatin secretions persisted. All diamidines tested suppressed the beta-cell function, with a log-dose-response proportionality, the mesylate compound being more potent than pentamidine isethionate, and the lipophilic analogs more than the hydrosoluble diamidines. Electron microscopy revealed distinct morphological alterations in islets exposed to pentamidine, the intensity of these changes being dose-and time-dependent, and the beta cells more severely damaged than the non-beta cells. 51Cr-labelled islet cells and RIN 5 F cells consistently appeared more sensitive to pentamidine cytotoxicity than rat fibroblasts, myeloma cells and hepatocytes. The pentamidine-induced suppression of beta-cell function was not, in conditions tested, affected by the presence of nicotinamide and the hexose concentration in the medium. The kinetics of islet damage were slower than those of streptozotocin and alloxan-induced islet damage. The present study confirms that pentamidine is selectively toxic to islet beta cells, with some features distinct from the alloxan and streptozotocin toxicities to these cells. The mechanism of this process and its precipitating factors in vivo need clarification.
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PMID:Functional and morphological modifications induced in rat islets by pentamidine and other diamidines in vitro. 389 20

Plasma cells obtained from the peripheral blood of a patient with multiple myeloma was incubated in serum and Krebs-Ringer bicarbonate buffer with (14)C-labeled glucose, acetate, and propionate. Glucose utilization by these cells amounted to 0.5 mumole per hr per 10(8) cells and was mainly via the Embden-Meyerhof pathway, and only 6% or less traversed the hexose monophosphate shunt. The presence of Krebs cycle activity was demonstrated by direct isolation of several labeled intermediates after incubation with either (14)C-acetate or (14)C-propionate. The distribution of (14)C in lactate, succinate, fumarate, malate, aspartate, and glutamate indicate a complete Krebs cycle. Acetate was metabolized via the Krebs cycle to the extent of 0.15 mumoles per hr per 10(8) cells, and the rate of propionate utilization was 0.17 mumoles per hr per 10(8) cells.
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PMID:Carbohydrate metabolism in leukocytes. VII. Metabolism of glucose, acetate, and propionate by human plasma cells. 602 50

The denaturation of IgE immunoglobulin induced by heating at 56 degrees C or by treatment at low pH is inhibited in the presence of high concentrations of salts or hexoses. Between 50 and 100% of the IgE anaphylactic activity (PCA) of rat and mouse antisera is recovered after heating at 56 degrees C for 1,5 or 5 h, respectively, in 1 M MgSO4 or 2 M glucose, mannose or fructose. Anaphylactic activity of IgE monoclonal anti-DNP mouse antibody is equally preserved. The specific antigenic determinants of human and rat IgE myeloma proteins are also thermostable in these conditions. The addition of MgSO4 or glucose protects IgE anaphylactic antibodies against denaturation at pH 2. It is suggested that IgE denaturation is the consequence of interactions between molecules of immunoglobulin and that such interactions are diminished by steric hindrance in a medium containing high concentrations of ions or hexose molecules.
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PMID:Influence of the medium on the heat and acid denaturation of IgE. 665 41

This study assessed the changes in the isoprenoid pathway and its metabolites digoxin, dolichol and ubiquinone in multiple myeloma. The following parameters were assessed: isoprenoid pathway metabolites, tyrosine and tryptophan catabolites, glycoconjugate metabolism, RBC membrane composition and free radical metabolism. There was elevation in plasma HMG CoA reductase activity, serum digoxin and dolichol and a reduction in RBC membrane Na+ - K+ ATPase activity, and serum ubiquinone levels. Serum tryptophan, serotonin, nicotine, strychnine and quinolinic acid were elevated while tyrosine, dopamine, noradrenaline and morphine were decreased. The total serum glycosaminoglycans and glycosaminoglycan fractions, the activity of GAG degrading enzymes and glycohydrolases, carbohydrate residues of glycoproteins and serum glycolipids were elevated. The RBC membrane glycosaminoglycans, hexose and fucose residues of glycoproteins, cholesterol and phospholipids were reduced. The activity of all free radical scavenging enzymes, concentration of glutathione, iron binding capacity and ceruloplasmin decreased significantly while the concentration of lipid peroxidation products and NO increased. Hyperdigoxinemia related altered intracellular Ca++ mediated oncogene activation, dolichol induced altered glycoconjugate metabolism and ubiquinone deficiency related mitochondrial dysfunction can contribute to the pathogenesis of multiple myeloma. The biochemical findings reported could be the cause or the consequence of multiple myeloma.
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PMID:Isoprenoid pathway related cascade in multiple myeloma. 1285 16

Various preparations of gamma-globulin homogeneous in the ultracentrifuge showed a similar content of hexose, hexosamine, fucose, and sialic acid. Subfractionation of Fr. II gamma-globulin by zone electrophoresis revealed multiple components of different mean mobilities but containing similar amounts of carbohydrate. Gamma globulin isolated directly from normal serum by zone electrophoresis showed a heavy component in addition to the usual 7 S material. The heavy component (s(20, w) = 19 S) concentrated by preparative ultracentrifugation was found to be considerably richer in carbohydrate than the rest of the gamma-globulin and accounted for small differences in carbohydrate content between different preparations of gamma-globulin. Pathological sera with marked elevation in gamma-globulin showed a carbohydrate-protein ratio for the gamma-globulin similar to that found for the corresponding 7 S fraction in normal serum. This was only partially true of the myeloma proteins with a mobility in the gamma-globulin region. Certain of these proteins showed slight but significant differences. The myeloma proteins of faster mobility (beta-myelomas) contained considerably more carbohydrate. The possible role of these carbohydrates in accounting for some of the mobility and immunological differences in the myeloma proteins is discussed. The pathological proteins found in two cases of macroglobulinemia showed a high carbohydrate content similar to but slightly lower than the normal 19 S component of gamma-globulin.
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PMID:The carbohydrate of gamma-globulin and myeloma proteins. 1334 70

Physicochemical characterization of mouse myeloma proteins revealed the individuality of each myeloma protein. When the myeloma proteins are considered collectively a wide range of individual properties were represented, including electrophoretic mobilities varying from the gamma to alpha region, hexose contents from 1 to 4 per cent, and ultracentrifugal components from 6.5 to 13 S. The 20 myeloma proteins could be divided into groups, the gamma type and the beta type myeloma globulins, on the basis of physicochemical, as well as immunoelectrophoretic, studies. Two gamma type myeloma proteins (5563, MPC-11) resembled normal gamma globulins, sedimenting as a single 6.5 S peak in the ultracentrifuge, and having a relatively low hexose content (1 per cent). Eighteen beta type mouse myeloma proteins differed from gamma myeloma proteins and, typically, were found on ultracentrifugal analysis to have multiple components with sedimentation coefficients of 6.5, 9, 11, and 13 S, having a higher hexose content (2 to 4 per cent) as well as distinctive chromatographic and starch gel electrophoretic properties. All of the mouse myeloma proteins were heterogeneous and heterogeneity of two types was observed. Polymer formation was responsible for the 9, 11, and/or 13 S components seen on ultracentrifugation of the beta type myeloma proteins. Starch gel electrophoresis revealed this type of heterogeneity as relatively widely separated myeloma protein components, presumably owing to the retardation effect of starch gel on the electrophoretic migration of the larger polymers. Starch gel electrophoresis revealed a different type of heterogeneity for the two gamma type myeloma proteins, each of these being shown to contain 5 or more components differing only in electrophoretic properties. The physicochemical characteristics of the gamma-type and beta-type myeloma proteins in the mouse indicated the close similarity of these proteins to the gamma- and beta-(2A)-myeloma proteins in man.
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PMID:Physiocochemical characterization of mouse myeloma proteins: demonstration of heterogeneity for each myeloma globulin. 1369 3

This study assessed the changes in the isoprenoid pathway and its metabolites digoxin, dolichol, and ubiquinone in multiple myeloma. The isoprenoid pathway and digoxin status were also studied for comparison in individuals of differing hemispheric dominance to find out the rote of cerebral dominance in the genesis of multiple myeloma and neoplasms. The following parameters were assessed: isoprenoid pathway metabolites, tyrosine and tryptophan catabolites, glycoconjugate metabolism, RBC membrane composition, and free radical metabolism--in multiple myeloma, as well as in individuals of differing hemispheric dominance. There was elevation in plasma HMG CoA reductase activity, serum digoxin, and dolichol, and a reduction in RBC membrane Na(+)-K+ ATPase activity, serum ubiquinone, and magnesium levels. Serum tryptophan, serotonin, nicotine, strychnine, and quinolinic acid were elevated, while tyrosine, dopamine, noradrenaline, and morphine were decreased. The total serum glycosaminoglycans and glycosaminoglycan fractions, the activity of GAG degrading enzymes and glycohydrolases, carbohydrate residues of glycoproteins, and serum glycolipids were elevated. The RBC membrane glycosaminoglycans, hexose, and fucose residues of glycoproteins, cholesterol, and phospholipids were reduced. The activity of all free-radical scavenging enzymes, concentration of glutathione, iron binding capacity, and ceruloplasmin decreased significantly, while the concentration of lipid peroxidation products and nitric oxide increased. Hyperdigoxinemia-related altered intracellular Ca++/Mg++ ratios mediated oncogene activation, dolichol-induced altered glycoconjugate metabolism, and ubiquinone deficiency-related mitochondrial dysfunction can contribute to the pathogenesis of multiple myeloma. The biochemical patterns obtained in multiple myeloma are similar to those obtained in left-handed/right hemispheric chemically dominant individuals by the dichotic listening test. But all the patients with multiple myeloma were right-handed/left hemispheric dominant by the dichotic listening test. Hemispheric chemical dominance has no correlation with handedness or the dichotic listening test. Multiple myeloma occurs in right hemispheric chemically dominant individuals and is a reflection of altered brain function.
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PMID:Hypothalamic digoxin, hemispheric chemical dominance, and oncogenesis: evidence from multiple myeloma. 1460 44

The antigenic properties of normal 19S gamma-globulin, pathologic macroglobulins, beta(2A)-myeloma proteins, and Bence Jones proteins have been compared with 7S gamma-globulin and the small 3.5S units derived from it by gel diffusion precipitin techniques. These studies demonstrate that the determinant groups on the 7S gamma-globulin molecule responsible for the cross-reaction with each of the other proteins are associated with the two fragments of 7S gamma-globulin which have the antibody-combining sites. The antigenic specificity of the 7S gamma-globulin which distinguishes it from each of these proteins is associated primarily with the fragment that is richest in hexose and can not combine with antigen. However when compared with certain of the paraproteins additional antigenic specificity was also found to reside in the fragments with antibody-combining activity. The finding of similar antigenic relationships in rabbit gamma-globulins suggests that some of the biological properties associated only with the 7S gamma-globulins and not with the other immune globulins may reside in the fragment which also carries the antigenic specificity of the protein.
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PMID:ANTIGENIC RELATIONSHIPS BETWEEN IMMUNE GLOBULINS AND CERTAIN RELATED PARAPROTEINS IN MAN. 1986