Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to elucidate the question of whether the maturation defect in vivo in acute leukemia is due to environmental or cellular factors, we have cultured human leukemic cells in a nonleukemic milieu, i.e., diffusion chambers implanted into the abdominal cavity of normal and irradiated mice. For each harvest, the cell count was measured and differential counts and the number of peroxidase-positive cells determined. The cell number decreased with time, without significant difference between culture in irradiated (500 rads) and normal mice. The blast cells succeeded only in developing distorted promyelocytes and myelocytes. There was a general pattern of increase in the number of peroxidase-positive cells. The study supports the concept that acute myeloid leukemia (AML) is a disturbance of cellular maturation due to cellular rather than environmental defects.
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PMID:Cultivation of leukemic human bone marrow cells in diffusion chambers implanted into normal and irradiated mice. 4 61

A transplantable myelogenous leukemia of an inbred Wistar/Furth rat has been established in tissue culture and cloned. The resulting transplantable leukemia line demonstrates in vitro doubling time of 20 hr, colony-forming efficiency of 5% in liquid and methylcellulos-containing medium, and a saturation density of 3.0 x 106 cells/sq cm in liquid medium. Following intraperitoneal inoculation, newborn rats developed solid tumors, ascities, and leukemia with ld50 of5 x 103 cells and mean latency of 60 days. The tumor cell morphology was consistent with that of acute myelogenous leukemia. Histochemical staining for myeloid enzymes revealed no evidence of myeloperoxidase, esterase, or leukocyte alkaline phosphatase; however, fluorescent antibody staining for lysozyme was markedly positive. Serum, urine, and ascitic fluid from rats with transplanted leukemia also contained elevated levels of lysozyme. There was no detectable type-CRNA virus production by this cell line after as long as 100 days in vitro. This inbred rat myelogenous leukemia should provide a useful model for studies of chemotherapy and immunoltherapy of human acute myelogenous leukemia.
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PMID:Acute myelogenous leukemia of the Wistar/Furth rat: establishment of a continuous tissue culture line producing lysozyme in vitro and in vivo. 4 87

Granule formation was investigated in differentiating neutrophils of a patient with acute myelogenous leukemia (AML) by means of the combined techniques of electron microscopy and peroxidase cytochemistry. Two important pathologic features were observed: first, an abnormal concentration and packaging of peroxidase into Auer rods in leukemic promyelocytes, and second, the presence of Auer rods surrounded by single-unit membranes in some mature polymorphonuclear leukocytes (PMN). An additional unexpected finding was the discovery of two distinct populations of PMN circulating concurrently; a minor (less than 5%) normal one that contained both peroxidase-positive azurophilic and peroxidase-negative specific granules and a major abnormal one characterized by the absence of specific granules. None of these abnormalities was observed during the two remissions of this patient's disease. During relapse a "hiatus leukemicus" occurred, which also revealed two populations of cells, a majority population of leukemic blasts, and a minority population of a few normal PMN. These findings documented several developmental abnormalities in the differentiating cells of myelogenous leukemia and also suggested that concurrent normal and abnormal populations of PMN may be a helpful diagnostic feature of a leukemic process.
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PMID:Abnormalities in granule formation in acute myelogenous leukemia. 6 55

Peripheral blood myeloblasts from five patients with acute myeloblastic leukemia and peripheral remission leukocytes from two of these patients were radiolabeled by the lactoperoxidase-catalyzed surface radioiodination technique and incubated in a nutrient medium at 37 degrees. Radioactive materials shed from viable cells into the supernatant at 24 hr were purified by gel filtration and by DEAE-cellulose chromatography. The radiolabeled leukemic cells shed relatively few molecular species into the culture medium. The DEAE-cellulose eluate usually contained one major peak in which radioactivity and protein levels were coincident; the molecular weight of this compound was 350,000 to 400,000, and it contained carbohydrate as well as protein. Glycoprotein shed from leukemic cells was specifically reactive in a coprecipitation assay with defined antimyeloblast alloantisera obtained from leukemic patients receiving immunotherapy. No reaction was seen with antisera directed against HLA or B-cell antigens. Material shed from remission cells did not coprecipitate with antileukemic antisera. The isolation of radioactively labeled antigen derived from myeloblasts may ultimately allow the monitoring of human antigen levels in leukemic blood by radioimmunoassay.
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PMID:Isolation and partial characterization of radioiodinated myeloblastic leukemia-associated cell surface glycoprotein antigen. 8 80

During a large clinicopathologic study of acute nonlymphocytic leukemia (ANLL), ten patients were identified in whom the leukemic blasts demonstrated striking morphologic and cytochemical similarities and who seemed to form a specific subgroup of ANLL. The patients' leukemic blasts were studied in routine blood and bone marrow preparations and by cytochemical and ultrastructural techniques. In routine smears, the blasts showed no clear evidence of differentiation. Cytochemically, the blasts exhibited strongly positive nonspecific esterase activity, which was completely inhibited by incubation with sodium fluoride, and were myeloperoxidase and sudan black B negative. Ultrastructural features of the blasts were similar to those described for monocytic leukemias. Striking clinical features included the occurrence primarily in young patients, the high frequency of lymphadenopathy at presentation, and the high incidence of post-treatment disseminated intravascular coagulation. Complete remissions were frequently initially obtained with duanorubicin in combination with various other agents and later in the disease with VP16-213. Based on the cytochemical and ultrastructural features, we concluded that this form of ANLL was a variety of acute monocytic leukemia. Recognition of the entity is important for optimal therapy.
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PMID:Acute monoblastic leukemia: diagnosis and treatment of ten cases. 16 29

Untreated patients with acute granulocytic leukemia showed impairment of microbicidal activity and,, in one, this was associated with myeloperoxidase deficiency and staphylococcal infection. In chronic granulocytic leukemia, there was no significant impairment of microbial killing. However, reduction in the capacity to reduce nitro-blue tetrazolium indicated some disturbance of neutrophil function in this disorder.
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PMID:Granulocyte function in untreated acute and chronic granulocytic leukemia. 18 36

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

Ten cases of acute granulocytic leukemia with blast cells containing Auer bodies (ABs) have been studied by electron microscopy after cytochemical demonstration of myeloperoxidase. The cytochemical dense reaction product has been used as a dark field to visualize unreactive protein of ABs which may then be easily identified by its negative contrast. This method has allowed us to identify three types of ABs which differ in their substructure. In type I, (five patients with promyelocytic leukemia), our study confirmed that all of the ABs consisted of a hexagonal arrangement of hollow tubes. Cells from four cases of acute myeloblastic leukemia displayed type II ABs, in which a unique pattern of protein associated in a regular linear arrangement with well defined periodicity was identified. Type III appeared characteristic of a subclass of acute myeloblastic leukemia in which large inclusions with Chediak-Higashi-like granules containing numerous micro-ABs were seen. The configuration, size, and organization of the protein in the crystal were distinct from those seen in the two other types of ABs. These features suggest that the nature of the protein in ABs may be heterogeneous.
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PMID:Three types of Auer bodies in acute leukemia. Visualization of their protein by negative contrast after peroxidase cytochemistry. 22 15

A simple cytochemical and cytobacterial method for the simultaneous demonstration of peroxidase and lysozyme (muramidase) activities in individual cells was devised. In characterization of myeloid and monocyte series, the combination of these myeloid- and monocyte-specific enzymes not only was more informative than a single enzyme but made it easier to differentiate acute myelomonocytic leukemia, with higher lysozyme activity, from acute myeloid leukemia, with higher peroxidase activity. Acute lymphocytic leukemia had no lysozyme or peroxidase activity.
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PMID:Simultaneous demonstration of peroxidase and lysozyme activities in leukemic cells. 26 61

Cytogenetic studies were performed in 546 patients with acute leukemia between 1968 and 1975. Two hundred thirty-four patients were aneuploid (42.9%), and 312 patients were diploid (57.1%). Among these, 32 patients were found to exhibit similar chromosomal alterations that appeared to involve specifically chromosomes 8 and 21. Banding studies in at least 15 of these patients confirmed the presence of a translocation between these two chromosomes. The cytogenetic findings were correlated with the hematologic and clinical data. It was found that each of these individuals had a typical picture of acute granulocytic leukemia with Auer rod-positive and peroxidase-positive cells. Ultrastructurally, the patients in this group also consistently demonstrated the presence of a nuclear bleb that has been positively associated with aneuploidy in acute leukemia. Clinically, they seemed to respond better to therapy than other adult patients with acute granulocytic leukemia. It is proposed that the 8/21 translocation acute leukemia represents a definite subgroup within the general category of acute granulocytic leukemia, with an incidence of approximately 7.3%.
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PMID:Hematologic and cytologic characterization of 8/21 translocation acute granulocytic leukemia. 28 82


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