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

This study investigated the hematologic abnormalities of an infant with propionic acidemia and reversible pancytopenia. Light and electron microscopy of her bone marrow revealed severely disturbed cellular morphology with trilineage dysmyelopoiesis, hemophagocytosis, and numerous multinucleated histiocytes and megakaryocytes. The effects of her serum and of organic acids associated with propionic acidemia were studied on hematopoiesis in vitro. Mouse erythroid (CFU-E) and granulocyte-monocyte colonies (CFU-GM) were assayed by fibrin clot technique; human CFU-GM were grown in agar culture. The infant's serum reduced mouse CFU-E and CFU-GM by 43 and 32%, respectively, compared with normal human sera, but had no effect on human CFU-GM in our culture system. Buffered propionic acid caused concentration-dependent inhibition of mouse CFU-E and human CFU-GM over a range reported in sera of acutely ill infants with propionic acidemia. Neither cell viability nor subsequent colony formation was diminished by preincubation of bone marrow cells with propionic acid for 48 h. The three other organic acids studied, tiglic acid, 3-OH propionate, and glycine, did not inhibit growth of mouse CFU-E, CFU-GM, or human CFU-GM, and glycine significantly enhanced formation of the latter. Evaluation of the infant's hematologic abnormalities suggests that inhibition of bone marrow proliferation and maturation and, perhaps, shortened red blood cell survival were responsible for her pancytopenia. The studies performed in vitro implicate propionic acid in this hematopoietic dysfunction.
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PMID:Pancytopenia in propionic acidemia: hematologic evaluation and studies of hematopoiesis in vitro. 373 92

Bone marrow biopsies of patients with a myelodysplastic syndrome (MDS) may, in the absence of an increased number of blasts in the bone marrow smears, contain small clusters of immature precursors. The presence of these cell nests, previously described as "abnormal localized immature precursors" or ALIP, bears a strong prognostic value predisposing patients to early death with an increased risk to develop myeloid leukaemia. In order to describe and delineate this histological characteristic more precisely, we compared bone biopsies of patients with MDS, used in these previous studies, with bone marrow biopsies performed for staging procedures in patients with Hodgkin's disease, non-Hodgkin's lymphoma and carcinoma. From this comparison we conclude that immature precursors are readily differentiated from proerythroblasts, myeloblasts and small-sized megakaryocytes, and that they most probably represent precursors of the myelo-monocytic-erythroid series. A clearcut increase in their number, mostly resulting in the formation of small clusters, is only found in biopsies from patients with MDS.
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PMID:The histological characterization of ALIP in the myelodysplastic syndromes. 376 79

Eighteen patients with myelodysplastic syndrome received 13-cis-retinoic acid (1.0-mg/kg/day starting dose with 0.5-mg/kg increment escalations) in a phase I-II trial. Two partial responses involving the erythroid series were observed in four patients with primary refractory anemia with ring sideroblasts. One of two patients with chronic myelomonocytic leukemia also achieved a partial response. No other responses were found in the remaining patients, which included eight with refractory anemia with excess blasts. In six patients drug toxicity necessitated termination of the trial. Four patients had unexpected drug-induced thrombocytopenia; three of these had low platelet counts before treatment. Two of the six patients had other toxic effects. Further studies are warranted to evaluate the effectiveness of 13-cis-retinoic acid in patients with refractory anemia with ring sideroblasts and chronic myelomonocytic leukemia. At moderate doses significant toxic effects, including thrombocytopenia, are not uncommon.
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PMID:Phase I-II study of 13-cis-retinoic acid in myelodysplastic syndrome. 386 1

A detailed study of 43 newly diagnosed cases of myelodysplastic syndrome (MDS) shows that many of the morphological features of blood and bone marrow are common to the different FAB groups. In addition, there is no clear distinction between the groups with regard to CFU-E, BFU-E or CFU-GM colony growth in vitro or ferrokinetic assessment of erythropoiesis in vivo. The interrelationships between all the parameters we have studied have been examined and there is little correlation between erythroid colony formation in vitro, the percentage erythroblasts in the bone marrow, erythroid output measured by ferrokinetics and the peripheral blood reticulocyte count, all of which appear to measure different aspects of erythropoiesis. Reduced erythroid colony growth and a high degree of ineffective erythropoiesis in vivo are common in all groups and appear to be an early manifestation of abnormal function. Decreasing marrow iron turnover is more closely related to increasing numbers of marrow blast cells than any other index of erythropoiesis.
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PMID:The myelodysplastic syndrome: analysis of laboratory characteristics in relation to the FAB classification. 397 Aug 59

Certain new hematologic findings in eight homosexual or bisexual patients with the acquired immune deficiency syndrome (AIDS) are presented. All eight patients manifested a normochromic, normocytic anemia, and six of eight had granulocytopenia during their hospitalization. The other two had low-normal granulocyte counts. Bone marrow examination showed normocellular or hypercellular marrows with increased myeloid: erythroid ratios and increased numbers of megakaryocytes. All patients had abnormalities in maturation of all cell lines, most prominent in the granulocytic series. This constellation of features is similar to the findings in the myelodysplastic syndromes (preleukemia). The authors suggest that myelodysplasia in patients with AIDS results in ineffective hematopoiesis and contributes to the peripheral blood cytopenias found in these patients. Myelodysplasia could be a direct or indirect effect of human T-lymphotropic retrovirus-III (HTLV-III).
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PMID:Myelodysplasia in the acquired immune deficiency syndrome. 402 20

Acid alpha naphthyl acetate esterase (ANAE) and combined ANAE-chloroacetate esterase cytochemistry was performed on 121 bone marrow aspirates from primary myelodysplastic syndromes (MDS) and a secondary dysplasia-megaloblastic anaemia (MA). The investigation demonstrated the presence of abnormal ANAE positive granulocyte populations in a significant proportion of cases. These cells, in which the staining patterns were characterized by atypical granular ANAE positivity and double ANAE-chloroacetate reactions, were shown immunologically to lack the receptor and antigenic characteristics of monocytes and morphologically to be granulocytes. Isoelectric focusing, however, indicated that the atypical esterase cytochemistry of these granulocytes was due to the presence of markedly increased concentrations of ANAE isoenzymes usually found in monocytes. Atypical ANAE-staining granulocytes were particularly evident in MDS marrows showing sideroblastic erythroid changes, whilst in MA they were mainly seen in cases of intermediate severity. It is suggested that these cells are associated with dysmyelopoietic changes in both malignant and non-malignant conditions.
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PMID:Esterase cytochemistry in primary myelodysplastic syndromes and megaloblastic anaemias: demonstration of abnormal staining patterns associated with dysmyelopoiesis. 658 35

The haematological features of 118 cases of primary myelodysplastic syndromes (PMDS) were reviewed to see how these could be related and classified according to the recent FAB proposals. A majority of the cases were elderly who presented with a macrocytic or normocytic anaemia and reticulocytopenia. Cases of acquired idiopathic sideroblastic anaemia (AISA) usually had normal leucocyte and platelet counts, erythroid hyperplasia, marked dyserythropoiesis and more than 20% ringed sideroblasts. Cases of refractory anaemia with excess of blasts (RAEB) had frequent neutropenia and thrombopenia usually with prominent dysgranulopoiesis and dysthrombopoiesis. Refractory anaemia or refractory cytopenia appeared morphologically to be a heterogeneous group. Leukaemic transformation did not occur in any of these 16 cases of AISA whereas six of the 34 cases of RAEB transformed into acute leukaemia. It appears that the cases of PMDS present with well defined haematological features which permit recognition of different groups; these latter groups appear to be morphologically and prognostically distinct.
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PMID:Haematological features of primary myelodysplastic syndromes (PMDS) at initial presentation: a study of 118 cases. 661 10

Hematopoiesis was investigated in a 14-yr-old girl who had a 2-yr history of stable asymptomatic pancytopenia and who was also heterozygous at the structural locus for glucose-6-phosphate dehydrogenase (G-6-PD). There was no morphologic or cytogenetic evidence for preleukemia and no suggestion of Fanconi anemia. In the skin and sheep erythrocytes-rosetted T lymphocytes, the ratio of G-6-PD A/B activities was 1:1. However, only type B activity was found in peripheral blood erythrocytes, granulocytes, and platelets. Most erythroid bursts and all granulocyte/macrophage colonies formed in methylcellulose culture were derived from the abnormal clone. These findings demonstrate that (a) some cases of pancytopenia are stem cell diseases that apparently develop clonally; (b) circulating differentiated cells originate from this clone; (c) despite a hypoproliferative anemia, the in vivo expression of presumably normal (nonclonal) progenitors is suppressed. In this patient, the relationship between clonal dominance and possible malignancy may be assessed prospectively.
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PMID:Pancytopenia as a clonal disorder of a multipotent hematopoietic stem cell. 669 Apr 81

Colony formation by haematopoietic progenitors from the bone marrow was studied in 44 patients with a myelodysplastic syndrome. Erythroid progenitors BFU-E and CFU-E were cultured in methyl cellulose, and granulocyte-macrophage precursors CFU-GM in agar. 3 of 32 patients showed normal numbers of BFU-E colonies; in all the other cases the number of these colonies was below the normal range. CFU-E colony formation was subnormal in all cases. 23 of 44 patients grew normal numbers of colonies and clusters in CFU-GM cultures. These patients had refractory anaemia with ring sideroblasts (FAB-classification) or 5q-karyotype anomaly in the marrow. Patients lacking both of these findings exhibited reduced colony formation or excessive growth of colonies and/or clusters, with few exceptions. In conclusion, we found that erythroid colony formation was defective in all cases. Normal granulocyte-macrophage colony formation was associated with refractory anaemia with ring sideroblasts or the presence of 5q- karyotype anomaly.
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PMID:Erythroid and granulocyte-macrophage colony formation in myelodysplastic syndromes. 671 44

A patient with severe anemia, reticulocytopenia, and erythroid hyperplasia of the bone marrow developed fatal acute nonlymphocytic leukemia after 3 yr. A Philadelphia chromosome with the typical 9/22 translocation t(9q +;22q-) was identified by banding techniques in a small number of bone marrow cells throughout the preleukemic phase of the illness (14%--38% of metaphases) and during the acute transformation (50%). Granulocytic colony formation in vitro was abnormal in the preleukemic phase. The diagnosis of chronic granulocytic leukemia was excluded on the basis of clinical and laboratory findings. The identification of the Ph1 chromosome in this form of chronic myelodysplastic syndrome (preleukemia) provides a new example of a hematologic disorder predisposing to acute leukemia in which this chromosomal abnormality occurs.
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PMID:Chronic myelodysplastic syndrome (preleukemia) with the Philadelphia chromosome. 693 Sep 80


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