Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It was shown by Pincus and Klebanoff that a correlation existed between leukocytic iodination measured in vivo and microbicidal leukocytic activity. We have analyzed the results of this test in relation to time and in the presence of variable quantities of polymorphonuclear leukocytes (PMN). The values observed per time and PMN unit proved to be equivalent in the presence of 2.5 X 105 PMN or 5.0 x 105 PMN per 0.5 ml of incubation medium, measured after 10, 20 and 30 minutes or in the presence of 1.0 x 106 PMN, measured after 10 minutes. That is to say iodination is proportional to leukocyte concentration and incubation time. Increase of either the quantity of cells or the incubation time, beyond the area we defined, reduced iodination per cell and per unit of time. Concerning the patients with an insufficient iodination, we have studied 2 parameters in the presence of 5.0 x 105 PMN: 1) initial iodination measured after 10 and 20 minutes and 2) stability of iodination measured after 60 minutes. These two parameters were equally affected in two cases with myelofi-rosis, 3 patients with acquired refractory anaemia, one with chronic lymphoid leukaemia, one with erythroleukaemia, one with hairy cell leukaemia, one with systemic mastocytosis and almost complete myeloperoxidase dificiency, one with sickle cell disease, two with liver diseases and two with chronic myeloid leukaemia. The iodination at the 60th minute was more affected than at the 10th minute with a patient with myelofibrosis and 4 other patients with acquired refractory anaemias. The significance of these differences is not well understood; however the meaning of the decrease in the iodination of whatever type is that a PMN anomaly exists directly related to the myeloperoxidase H2O2 halogenation system, or to one of the stages of engulfment and/or metabolic events preceeding it and leading to the production of H2O2. This test, with the alterations we introduced, is suggested as a test for detection of functional PMN abnormalities.
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PMID:Quantitative iodination of human blood polymorphonuclear leukocytes. 16 86

The functional capacities of granulocytes in patients with chronic granulocytic leukemia are still a subject of controversy, probably due to the heterogeneity of the abnormalities observed from patient to patient. For a better definition of these abnormalities, 14 patients with untreated chronic granulocytic leukemia were studied. The patients were divided into three groups on the basis of the functional activities of their phagocytosing granulocytes. In four patients (group I), the granulocytes were normal in respect to particle ingestion, nitroblue tetrazolium (NBT)-stimulated reduction, cyanide-insensitive oxygen (O2) consumption, superoxide anion (O2-)-stimulated production, hydrogen peroxide (H2O2) production, and iodination. They also had a normal myeloperoxidase (MPO) content. In four patients (group III), the granulocytes were significantly defective in all of these activities. In the six remaining patients (group II), all the initial metabolic steps of the phagocytosing granulocytes (ingestion, NBT reduction, O2 consumption, O2-production, H2O2 production) were normal, as were the MPO content of the granulocytes, while iodination was strikingly decreased. These metabolic features suggested a degranulation defect which was observed ultrastructurally in the only patient studied among these six. The phagocytosing granulocytes of this patient did not degranulate and no deposits of MPO activity were seen in the phagosomes.
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PMID:Metabolic activity of phagocytosing granulocytes in chronic granulocytic leukemia: ultrastructural observation of a degranulation defect. 19 42

Unique fusiform or spindle-shaped particles (Phi bodies) and rods with hydroperoxidase (catalase and/or peroxidase) activity are present in human granulocyte precursors only in acute myelogenous leukemia (AML). These newly recognized particles are much more numerous and prominent than Auer rods. They may be rapidly and readily identified using the microscope in marrow or peripheral blood films when the procedures recommended in this paper for fixation, incubation for hydroperoxidase demonstration in 3,3'-diaminobenzidine (DAB)/H2O2 medium, copper salt treatment and counterstaining (optional) with the Papanicolaou method are employed. Films prepared in the same manner but treated with benzidine/H2O2 medium for myeloperoxidase did not reveal these particles. We believe that Phi bodies are pathognomonic of AML since they are almost invariably present in AML patients with active disease. Their presence serves to distinguish AML from acute lymphocytic leukemia and from chronic granulocytic leukemia in blast crisis. Since the particles disappear in disease remission and reappear upon relapse, the recommended procedure is not only useful in diagnosis but in guiding therapy. When a very rapid diagnosis is needed, it is not necessary to counterstain the preparations, but the nuclei, cytoplasm and plasmalemma can readily be observed in the granulocyte precursors when they are counterstained by the Papanicolaou method. This treatment does not diminish the clarity of the Phi bodies and rods which stain by virtue of their peroxidatic activity. This cytochemical diagnostic procedure should be considered for adoption by hematology laboratories.
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PMID:The light microscopic demonstration of hydroperoxidase-positive Phi bodies and rods in leukocytes in acute myeloid leukemia. 21 54

Recombinant tumor necrosis factor (rTNF) and rIFN-gamma induce in the human leukemia cell lines HL-60, ML3, and U937 the accumulation of transcripts of the X chromosome-linked chronic granulomatous disease (X-CGD) gene, encoding the 91-kD heavy chain of cytochrome b-245, a component of the NADPH oxidase of phagocytic cells. The gene is induced within 6 h by either cytokine, and its accumulation is observed upon induction with rIFN-gamma up to 5 d. The combined effect of the two cytokines is more than additive. rIFN-gamma also induces accumulation of X-CGD mRNA in immature myeloid cells from peripheral blood of chronic myeloid leukemia (CML) patients, whereas rTNF has almost no effect. The cells from CML patients constitutively express TNF mRNA, suggesting that endogenously produced TNF may play a role in the effect of rIFN-gamma on these cells. rTNF induces X-CGD gene expression in the myeloid cell lines acting, at least in part, at the transcriptional level, as shown in nuclear run-on experiments. The gene encoding the 22-kD light chain of cytochrome b-245 is constitutively expressed in the human myeloid cell lines and the accumulation of its transcripts is affected by neither rTNF nor rIFN-gamma, rTNF and rIFN-gamma synergistically to induce the cell lines to express the cytochrome b-245 heterodimer (as evaluated by its visible spectrum), and to produce NADPH oxidase activity and H2O2 upon stimulation with phorbol diesters.
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PMID:Tumor necrosis factor and immune interferon synergistically induce cytochrome b-245 heavy-chain gene expression and nicotinamide-adenine dinucleotide phosphate hydrogenase oxidase in human leukemic myeloid cells. 249 43

Granulocyte functions, viz. endocytosis, NADPH oxidase activity and iodination by leukocytes, were studied in granulocytes isolated from 17 chronic myeloid leukemia (CML) patients at initial diagnosis (stage I), from 10 patients in relapse (stage II), and 10 patients in acute blastic crisis (stage III). The mean phagocytic index of granulocytes from CML patients was similar to the normal value. NADPH activity decreased as the disease progressed. Thus, the amount of formazan produced was lower in granulocytes from patients in stage II (P less than 0.05) and stage III (P less than 0.01) than that produced by normal granulocytes. H2O2-Myeloperoxidase-dependent iodination was found to be significantly reduced in granulocytes from all stages of the disease compared to that of normal, stage I (P less than 0.01), stage II (P less than 0.05) and stage III (P less than 0.01). It thus seems that granulocyte function becomes less efficient as the disease progresses towards acute blastic crisis. Immature cells from the same patients carried out these functions at a more reduced level than did their mature counterparts.
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PMID:Studies on granulocyte functions in patients with chronic myeloid leukemia. 386 54

We have tried to improve existing methods for demonstration of platelet peroxidase (PPO) in human platelets and megakaryocytes by introducing a fixation of 0.1% glutaraldehyde prior to incubation in the DAB medium. This prefixation with low concentration of glutaraldehyde preserves excellent morphological detail and does not inhibit PPO activity. All 23 platelet-rich plasma samples show PPO reaction product in the dense tubular system after incubation in DAB medium with 0.003% H2O2. When 0.01% H2O2 is used in excessive DAB medium, PPO activity can also be demonstrated in platelets and megakaryocytes of bone-marrow cell suspensions. This method can be used for the identification of megakaryoblasts in acute non-lymphocytic leukemia, myelodysplastic syndromes and in blastic crisis of chronic myeloid leukemia. PPO cytochemistry can be combined with postfixation in a OsO4-ruthenium red mixture. This method reveals alpha-granules, dense bodies, microtubuli, glycogen, mitochondria, dense tubular system and invaginated membrane system in the same platelet and is useful for investigation of platelet ultrastructure.
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PMID:A reliable method with good cell preservation for the demonstration of peroxidase activity in human platelets and megakaryocytes. 619 33

We analyzed active oxygen (hydroperoxide; H2O2) production by peripheral neutrophils in various hematological diseases by flow cytometry. One hundred microliters of heparinized fresh blood was sequentially incubated at 37 degrees C with 2',7'-dichlorofluorescein diacetate and with or without phorbol myristate acetate (PMA). After hemolysis, the pelleted white blood cells were subjected to flow cytometry, and the neutrophil fraction was gated on the cytogram. Production of H2O2 by the fraction was estimated by determining the increase in the relative intensity of fluorescence emitted from the fraction in response to stimulation by PMA. In controlled chronic myelogenous leukemia (CML) (WBC < 1 x 10(10)/1), H2O2 production was normal, while in uncontrolled CML (WBC > or = 1 x 10(10)/1), it was reduced. In myelodysplastic syndrome (MDS), H2O2 production was also reduced, but no significant difference was observed among FAB classification disease types in MDS patients. In untreated acute non-lymphocytic leukemia (ANLL), H2O2 production was reduced, while in the complete remission stage of ANLL, its level was normal, suggesting recovery from normal clones. In aplastic anemia, the H2O2 production level was normal. Steroid therapy might be responsible for the reduction of H2O2 production in non-Hodgkin's lymphoma and multiple myeloma. The production of H2O2 is closely related to the oxygen-dependent bactericidal activity of neutrophils, and, hence, can be utilized as an index to indicate susceptibility to infection. This neutrophil function can be determined easily in ordinary clinical facilities by using flow cytometry, and care should be taken to prevent infection when H2O2 production is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Flow cytometric determination of active oxygen (hydroperoxide) produced by peripheral blood neutrophils in patients with hematological disorders. 836 85

The Maillard reaction has been implicated in cross-linking and fluorescence formation of collagen exposed to high glucose in vitro. However, several pharmacologic agents, whose action seems unrelated to pathways of nonenzymatic glycation, have been demonstrated to prevent cross-linking in diabetes. To clarify this discrepancy, kinetic changes in glycation, glycoxidation (carboxymethyllysine, CML), and cross-linking (measured as tendon breaking time, TBT) were evaluated in rat tail tendons incubated in 5 and 30 mM glucose in vitro and in tendons implanted in vivo into diabetic rat peritoneal cavity. In vitro, rates were found to be both O2- and glucose-dependent. Tendon preglycation and presence of added 2 mM glycosylamine and Amadori compounds (Amadori product of glucose and propylamine) catalyzed these changes in a primarily O2-dependent manner. In the presence of Amadori compounds, kinetic changes were dramatically increased and were preventable by addition of catalase to the medium. Tendons implanted into diabetic rat peritoneum became more rapidly glycoxidized and cross-linked when implanted at day 30 from diabetes onset (high tissue glycation) compared to day 3 (low tissue glycation) in spite of similar glycation kinetics, suggesting a mechanistic dissociation between glycation, glycoxidation, and cross-linking in diabetes. Indeed, intraperitoneal injection of catalase and other antioxidants dramatically suppressed cross-linking, fluorescence formation, and, to some extent, glycoxidation, without affecting glycation. This study confirms the role of oxidative stress in protein cross-linking by the Maillard reaction in vitro and provides the first evidence for a role of H2O2 in cross-linking in diabetes. Whereas Amadori products are a potent source of H2O2 formation in vitro, their precise contribution to H2O2 generation and the actual role of Maillard reaction products in collagen cross-linking in diabetes requires further investigation.
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PMID:Involvement of hydrogen peroxide in collagen cross-linking by high glucose in vitro and in vivo. 866 99

Aziridinylbenzoquinones are a group of antitumor agents that elicit cytotoxicity by generating either alkylating intermediates or reactive oxygen species. The mechanism of toxicity may not always, however, involve profound damage of cellular constituents, but may involve a cytostatic effect through interference with the cell cycle. In this context, we have examined the induction of the cell cycle inhibitor p21 (WAF1, CIP1, or sdi1), whose overexpression suppresses the growth of various tumor cells, in human tumor cells metabolizing 3,6-diaziridinyl-1,4-benzoquinone (DZQ) and its C2,C5-substituted derivatives: 2,5-bis-(carboethoxyamino) (AZQ) and 2, 5-bis-2(-hydroxyethylamino) (BZQ). Both DZQ and AZQ were effectively activated by HCT116 human colonic carcinoma cells; the activation of the former involved largely a dicoumarol-sensitive activity, whereas that of the latter appeared to be accomplished primarily by one-electron transfer reductases. BZQ was not a substrate for the dicoumarol-sensitive enzyme in HCT116 cells. Cellular activation of the first two quinones was associated with formation of oxygen-centered radicals as detected by EPR in conjunction with the spin trap 5,5'-dimethyl-1-pyrroline-N-oxide. The redox transitions of DZQ involved hydroxyl radical formation and were strongly inhibited by catalase, whereas those of AZQ showed a strong superoxide anion component sensitive to superoxide dismutase. These signals were suppressed by N-acetylcysteine with concomitant production of a thiyl radical adduct. This suggests an effective electron transfer between the thiol and free radicals formed during the activation of these quinones. DZQ and AZQ induced significantly the expression of p21 in HCT116 cells, but a 10-fold higher concentration of AZQ was required to achieve the level of induction elicited by DZQ. BZQ had little effect on p21 expression. p21 induction at both mRNA and protein levels correlated with the inhibition of either cyclin-dependent kinase activity or cell proliferation. p21 induction elicited by the above quinones was inhibited by N-acetylcysteine, whereas the non-sulfur analog, N-acetylalanine, was without effect. Catalase and superoxide dismutase did not effect p21 induction by aziridinylbenzoquinones in HCT116 cells, thus suggesting that extracellular sources of oxygen radicals generated by plasma membrane reductases have no influence in the expression of this gene. Hydrogen peroxide, a product of quinone redox cycling, elicited an increase of p21 mRNA levels in HCT116 and K562 human chronic myelogenous leukemia cells. The latter lacks p53, one of the activators of p21 transcription, thus suggesting that p21 expression can be accomplished in a p53-independent manner in these cells. This study suggests that p21 induction is mediated by an increase in the cellular steady-state concentration of oxygen radicals and that the greater effectiveness in p21 induction by DZQ may be related to its efficient metabolism by NAD(P)H:quinone oxidoreductase activity in HCT116 cells.
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PMID:Induction of p21 mediated by reactive oxygen species formed during the metabolism of aziridinylbenzoquinones by HCT116 cells. 894 36

Recent studies demonstrated N epsilon-(carboxymethyl)lysine (CML) in several tissue proteins. Incubation of proteins with glucose leads through a Schiff base to Amadori products. Oxidative cleavage of Amadori products is considered as a major route to CML formation in vivo, whereas it is not known which reactive oxygen species (ROS) is involved. The present study is undertaken to identify such a ROS. We prepared heavily glycated human serum albumin (HSA) which contained a high level of Amadori products, but an undetectable level of CML. Incubation of glycated HSA with FeCl2, but not with H2O2, led to CML formation which was enhanced by H2O2, but inhibited by catalase or mannitol, whereas superoxide dismutase had no effect. Similar data were obtained by experiments using Boc-fructose-lysine as a model Amadori compound. These data indicate that hydroxyl radical generated by the reaction of Fe2+ with H2O2 mediates CML formation from Amadori compounds.
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PMID:Hydroxyl radical mediates N epsilon-(carboxymethyl)lysine formation from Amadori product. 916 83


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