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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Published data on Japanese leukemia patients with a preleukemic hematological disorder were assessed. The reexamined cases were from the "Japona Centra Revuo Medicina" reported during the period from 1952 to 1971. Among preleukemic hematological disorders, hypoplastic anemia was the most frequently reported (41 of 62 cases). These "hypoplastic preleukemia" patients were rather elderly and terminated mostly in atypical myelocytic leukemia. The chief hematological feature of the hypoplastic preleukemia cases was the coexistence of a relative erythroid hyperplasia and a slight increase of myeloblasts in the bone marrow that was unusual in hypoplastic anemia. The presence of pancytopenia and hypocellular marrow with a relative erythroid hyperplasia combined with a slight increase of myeloblasts probably indicates hypoplastic preleukemia that terminates later in acute leukemia.
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PMID:Preleukemia: hematological disorders prior to onset of leukemia. 13 44

A 53-year-old male developed acute erythroleukemia three years after renal transplantation. He had received three years of immunosuppressive therapy with azathioprine. A preleukemia phase associated with chromosome abnormalities was recognized. Azathioprine has been associated with chromosome abnormalities. The chronic stimulation of an abnormal erythroid clone by transplantation may have hastened the development of erythroleukemia.
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PMID:Erythroleukemia in a renal transplant recipient. 37 1

The clinical, hematologic and histologic characteristics of six patients with refractory anemia with deletion of the long arm of chromosome No. 5 are described. These patients had a distinct hematologic picture with macrocytic anemia of mild to moderate severity, normal to low leukocyte count and increased platelet count. The long arm of chromosome No. 5 was deleted in the majority of bone marrow metaphases. The main cause of anemia was underproduction with decreased erythroid precursors in the bone marrow and no increase in peripheral blood reticulocytes. Two of five patients responded transiently to the administration of androgens. In vitro evaluation of the bone marrow growth pattern in semisolid agar culture system was performed in three patients and was found to be normal and distinct from that in patients with preleukemia. In a follow up of up to five years, no patient had changed hematologically and in none had leukemia developed. The 5q-syndrome is a distinct hematologic entity and probably more common than hitherto realized. This diagnosis may have therapeutic and prognostic implications.
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PMID:Macrocytic anemia, thrombocytosis and nonlobulated megakaryocytes: the 5q-syndrome, a distinct entity. 45 27

Hemopoietic cell proliferation was studied in a patient suffering from preleukemia characterized by peripheral pancytopenia and hypercellular bone marrow with ineffective erythropoiesis. Two years later when overt acute myelogenous leukemia had developed the study was repeated. The kinetics of proliferation were investigated by a new method which allows evaluation of the rate and time of DNA synthesis in individual morphologically defined cells. Erythropoiesis was found ineffective to the same degree in both stages of disease. The rate of erythroid cell proliferation, however, was reduced in overt leukemia only. The myeloid system showed a grossly reduced production rate of myeloblasts in preleukemia whilst the same parameter was strongly increased in leukemia. This high production rate of myeloblasts in overt leukemia was interpreted as indication of a far-reaching self-maintenance of the myeloblast pool in this stage of disease. The proliferative activity of the individual myeloblasts was reduced already in preleukemia, and even more so in leukemia. In order to explain the amplification of the myeloblast pool with the onset of overt leukemia a change in the mode of myeloblast divisions is assumed. For this a transition from steady state to some degree of exponential growth gives the most plausible explanation.
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PMID:Proliferative behavior of hemopoietic cells in preleukemia and overt leukemia observed in one patient. 107 Apr 63

Hematopoietic growth factors were found as factors stimulating hematopoietic colony formation in in vitro culture system using bone marrow cells as a source of hematopoietic progenitor cells. Erythropoietin, a growth factor stimulating erythroid lineage has now been clinically used as an therapeutic agent for anemia of chronic renal failure. Macrophage colony-stimulating factor (M-CSF), a growth factor stimulating the production of leukocytes including monocytes and neutrophils has been clinically used as an agent for leukopenic patients after anti-cancer therapy. M-CSF improves a survival rate after bone marrow transplantation (BMT) through the reduction of mortality rate associated with BMT such as bleeding, engraftment failure and GVHD. M-CSF accelerated platelet production when injected to thrombopenic patients with solid tumor after anticancer therapy. Granulocyte CSF (G-CSF) is a most powerful agent for various kinds of neutropenia such as neutropenia after anti cancer therapy, neutropenia after BMT, aplastic anemia, chronic neutropenia of children and myelodysplastic syndrome. However, since G-CSF stimulates growth of leukemic cells in vitro, careful observations should be required when clinically used on leukemic patients. Clinical studies of granulocyte-macrophage CSF (GM-CSF) and interleukin 3 (IL-3) are now in progress, in which a promoting activity of leukocyte production of these factors is evaluated.
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PMID:[Clinical application of hematopoietic growth factor (IL-3, G-CSF, GM-CSF, and EPO)]. 127 40

The in vitro growth of circulating erythroid progenitors (BFU-E) populations and the production of burst-promoting activity (BPA) by T lymphocytes have been studied in 17 patients with myelodysplastic syndromes. Based on the in vitro growth patterns of BFU-E, four groups of patients have been identified: i) normal BFU-E growth; ii) low spontaneous BFU-E growth, but normal response to LCM; iii) impaired BFU-E response to LCM; iv) no BFU-E growth. The pattern of BFU-E growth seems to be related to the clinical stage of the disease rather than to the FAB subgroup to which the patients belong. The ability of T lymphocytes to stimulate BFU-E growth was significantly reduced in all patients. The possible mechanisms inducing the impaired production of BPA by T lymphocytes are discussed. The in vitro evaluation of circulating erythroid precursors can supply useful prognostic information and possibly indications concerning the responsiveness of erythropoietic stem cells to recombinant human erythropoietin in vivo.
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PMID:In vitro growth of erythroid progenitor cells (BFU-E) and production of burst-promoting activity (BPA) by T lymphocytes in patients with myelodysplastic syndromes. 129 50

Red cell adenosine deaminase (ADA-RBC) activity in patients with myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria is significantly increased compared to that observed in normal controls. ADA-RBC activity is not related to fetal hemoglobin concentration, but it is significantly correlated with hemoglobin concentration at diagnosis and with the degree of morphologic dysplasia in the erythroid lineage. The results of our study suggest that the observed enzymatic abnormality may constitute a non-specific manifestation of the stem cell alteration that determines these disorders.
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PMID:Biologic relevance of elevated red cell adenosine deaminase activity in myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria. 129 30

We have investigated proliferation in bone marrow trephine biopsies from 32 patients with normal or abnormal haemopoiesis, using the monoclonal antibody PC10, which detects proliferating cell nuclear antigen (PCNA), together with immunohistochemical markers of haemopoietic cell lineage. PCNA immunostaining revealed the pattern of proliferation within individual haemopoietic lineages in normal marrow. Two unexpected observations were made: of erythroid cells, only pro-erythroblasts and occasional early normoblasts reacted, and positivity of megakaryocytes was unrelated to nuclear lobulation or CD61 expression. The pathological cases represented conditions in which haemopoiesis is increased (reactive hyperplasia, chronic granulocytic leukaemia, myeloproliferative and myelodysplastic syndromes, megaloblastic anaemia). Increases in the number, and disturbances of the spatial organization, of PCNA-expressing cells were present to a variable extent in all cases. Sheets of PCNA-positive megaloblastoid erythrocytes were frequently found in myelodysplastic and myeloproliferative tissue, associated with marked disturbances in the spatial organization of all haemopoietic lineages. Cases of megaloblastic anaemia due to vitamin B12/folate deficiency also demonstrated greatly increased erythroid PCNA expression, with positivity in some giant metamyelocytes. In addition to reflecting increased proliferation, elevated PCNA expression in some bone marrow pathologies may be due to altered kinetics of the protein induced by disturbances in growth factor production.
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PMID:A study of cell proliferation in formalin-fixed, wax-embedded bone marrow trephine biopsies using the monoclonal antibody PC10, reactive with proliferating cell nuclear antigen (PCNA). 134 81

Material from 63 cases with primary myelodysplastic syndromes (P-MDS) (French-American-British [FAB] types: refractory anemia [RA] = 21; RA with ring sideroblasts [RARS] = 8; RA with excess of blasts (RAEB) = 10; RAEB in transformation (RAEBt) = 6; chronic myelomonocytic leukemia [CMML] = 10 and unclassifiable = 8, ie, bone marrow aspiration was inadequate and stringent FAB criteria were not applicable) was analyzed for bone marrow histologic and immunohistochemical patterns. Standard Giemsa, hematoxylin and eosin (H&E) and reticulin stains were used for morphologic assessment. To identify the cell lineage precisely, chloroacetate esterase staining and an indirect immunoperoxidase technique using mouse monoclonal antibodies CD15, CD68, HLA-DR, and rabbit polyclonal CD3 and UEA-1 (lectin) was developed on formalin-fixed paraffin embedded bone marrow biopsies (BMB). The immunohistochemical assessment permitted accurate identification of dysplastic features such as mononuclear and binuclear megakaryocytes, Pelger-Huet neutrophils, and binuclear erythroblasts. Additional bone marrow histologic and immunohistochemical features observed were heterogeneity of immunohistochemical staining in various cell lineages, megakaryocytic emperipolesis, alteration of bone marrow microarchitecture, intravascular clusters of hematopoietic cells, and the types of benign lymphoid aggregates. The nature of abnormally localized immature precursors (ALIP) was discerned. Three types of clusters of immature cells were found that were difficult to distinguish on Giemsa and H&E morphology, these were erythroid aggregates (n = 18); megakaryocytic aggregates (n = 4), and immature granulocytic and monocytic aggregates (n = 32). The bone marrow histologic and immunohistologic patterns permitted the identification of four groups of clinical relevance: Group 1, cases with predominant erythroid hyperplasia and without ALIP (n = 15); group 2, cases with prominent myeloid hyperplasia and presence of ALIP (n = 32); group 3, cases with hypoplastic MDS (n = 10); and group 4, cases with hyperfibrotic MDS (n = 6). Statistical analysis showed a significant difference in survival and leukemic transformation between groups 1, 2, 3, and 4, with cases in group 2 showing the worst prognosis with early death due to increased propensity to leukemic transformation and cytopenia-related complications (P less than .0001). We conclude that immunohistochemistry is feasible on routinely processed BMB and the information obtained is of diagnostic and prognostic importance in P-MDS. The phenotype of ALIP varies with the morphologic and histologic subtypes of MDS and the term should be reserved for cases in whom the clusters in the intertrabecular region are of myeloid (granulocytic and monocytic) lineage on immunohistochemistry.
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PMID:Primary myelodysplastic syndromes: diagnostic and prognostic significance of immunohistochemical assessment of bone marrow biopsies. 137 Feb 3

Erythropoiesis in response to erythropoietin (Epo) in myelodysplastic syndrome (MDS) in vitro and in vivo is severely impaired. We investigated the stimulative effect of c-kit ligand (KL) on the erythroid colony-forming abilities of bone marrow cells from 17 patients with MDS. The effects of normal donor-derived marrow were examined in comparison. Suppression of erythroid colony formation in MDS in response to Epo could not be restored by the addition of interleukin-3 (IL-3) to culture. In cultures dishes supplemented with KL, erythroid colony formation was dramatically enhanced, regarding both colony number and size. Colony-forming abilities by MDS progenitors were improved following costimulation with KL, particularly in refractory anemia (RA) and refractory anemia with ring sideroblasts (RARS); however, little enhancement was apparent following KL stimulation of marrow from patients with refractory anemia with excess of blasts (RAEB), refractory anemia with excess of blasts in transformation (RAEB-t), and chronic myelomonocytic leukemia (CMML). These results suggest that KL responsiveness of patients with low-risk MDS may still be intact, and that with progression to high-risk MDS, erythroid progenitors lose proliferative reactivity to both KL and Epo stimulation. KL may have a therapeutic role in restoring erythropoiesis in a subset of patients with MDS.
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PMID:Kit ligand improves in vitro erythropoiesis in myelodysplastic syndrome. 138 Dec 39


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