Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of the present study was to evaluate the incidence of bone marrow-derived multipotent (CFU-GEMM), megakaryocytic (CFU-Mk), erythroid (BFU-E), and granulocyte-macrophage (CFU-GM) progenitor cells in 22 patients with myelodysplastic syndromes (MDS), and to investigate the role of hematopoietic accessory cells (T-lymphocytes and monocytes) as a possible cause of growth derangement. As compared to normal controls (n = 15), growth values in the 22 patients (mean +/- SEM) were significantly reduced for CFU-GEMM (0.4 +/- 0.1 versus 7 +/- 1, P less than 0.0005), CFU-Mk (1.4 +/- 0.5 versus 18 +/- 4, P less than 0.0005), BFU-E (2.2 +/- versus 40 +/- 6, P less than 0.0005), and CFU-GM (19 +/- 5 versus 65 +/- 10, P less than 0.0005). The growth of CFU-GEMM was abnormal at an early stage in the clinical development of MDS, sometimes even when CFU-GM formation was still normal. Colony-formation was unaffected by removal of hematopoietic accessory cells. Although no correlation was found between the incidence of lineage-restricted progenitors and the degree of peripheral cytopenia, derangement of colony growth was more pronounced in patients with worse prognosis. We conclude that: (i) the grossly defective CFU-GEMM growth supports the concept of MDS as clonal disorders of hematopoietic multipotent stem cells; (ii) a progressive impairment of in vitro hematopoiesis occurs in association with the clinical progression of the myelodysplastic syndromes.
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PMID:In vitro growth of bone marrow-derived multipotent and lineage-restricted hematopoietic progenitor cells in myelodysplastic syndromes. 250 Nov 71

Factors which may influence haematopoietic recovery after allogeneic bone marrow transplantation were analysed. Forty-six evaluable patients transplanted with lymphocyte-depleted marrow for acute lymphoblastic leukaemia, acute non-lymphoblastic leukaemia, chronic myeloid leukaemia, myelodysplastic syndrome and severe aplastic anaemia were studied. The median time for platelet recovery to greater than or equal to 20 and to greater than or equal to 50 x 10(9)/l was 21 (9-72) and 26 (11-86) days respectively. The neutrophil recovery to greater than or equal to 0.5 x 10(9)/l and the leucocyte recovery to greater than or equal to 1.0 x 10(9)/l was 19 (8-47) and 18 (6-47) days respectively. No relation was found between the number of infused granulocyte-macrophage colony-forming cells, erythroid burst-forming cells, diagnosis, graft-versus-host disease, antibiotic administration and recovery. Addition of a continuous 6-day infusion of anthracyclines to the conditioning regimen delayed the median recovery of platelets, neutrophils and leucocytes by 7-9 days. Fever during aplasia also inhibited haematopoietic recovery. It is speculated that leakage of intracellular anthracyclines after bone marrow infusion or fever secondary to anthracyclines-induced oromucositis is responsible for the delayed bone marrow recovery.
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PMID:Anthracyclines added to the conditioning regimen for allogeneic bone marrow transplantation are associated with a slower haematopoietic recovery. 265 Jul 86

The in vitro effect of recombinant human GM-CSF (rHuGM-CSF) was tested on bone marrow-derived multilineage (CFU-GEMM) as well as megakaryocytic (CFU-Mk), erythroid (BFU-E), and granulocyte-macrophage (CFU-GM) progenitors in a group (n = 16) of patients with myelodysplastic syndromes (MDS). Hematopoietic progenitor cell growth was markedly impaired in MDS patients as compared to normal controls (p less than 0.05, at least). Recombinant HuGM-CSF supported the growth of CFU-GEMM, CFU-Mk, and BFU-E at lower, equivalent, or slightly higher frequencies that those found in cultures plated with medium conditioned by peripheral blood leukocytes (PHA-LCM), but it was invariably ineffective in improving growth values. Recombinant HuGM-CSF supported the growth of granulocyte-macrophage colonies in 15 of 16 cases. The overall incidence (mean +/- SEM) of CFU-GM in cultures containing rHuGM-CSF (5 ng/ml) was significantly higher than the one found in cultures stimulated with PHA-LCM (40 +/- 15 vs. 17 +/- 7, p less than 0.05). Upon culture with rHuGM-CSF (5 ng/ml), in 5 of 15 patients de novo colony formation was observed (8 +/- 4) and in 4 of 15 patients CFU-GM growth (129 +/- 33) fell within normal range. Doses of rHuGM-CSF higher than 5 ng/ml did not result in a further increase of MDS-derived colony formation. It is concluded that rHuGM-CSF (a) does not improve the growth of CFU-GEMM, CFU-Mk, and BFU-E; (b) may completely restore the growth of CFU-GM in a subgroup of MDS patients; (c) while ineffective in improving anemia and thrombocytopenia, its in vivo in MDS may correct leukopenia through an effect at the level of granulocyte-macrophage progenitor cell compartment, at least in a subset of highly responsive patients.
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PMID:Growth of human hematopoietic colonies from patients with myelodysplastic syndromes in response to recombinant human granulocyte-macrophage colony-stimulating factor. 265 96

In order to maintain adequate circulating numbers of blood cells, the bone marrow must produce billions of cells each day and must be able to rapidly increase production by 10-20-fold in response to infection and hemorrhage. The existence of circulating factors that regulate this process has been suspected for over 100 years. Recently, the genes encoding these growth factors were cloned and their functions are now identified. Interleukin-3 (IL-3) acts on the most primitive hematopoietic stem cell, driving this self-renewing cell to produce progeny of all hematopoietic lineages. Granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates the granulocyte-macrophage progenitor cell, as well as cells committed to the erythroid lineage, to differentiate. G-CSF and M-CSF stimulate the most differentiated myeloid progenitors to produce granulocytes and monocytes/macrophages, respectively. Erythropoietin stimulates the differentiation of late erythroid progenitors. In the lymphoid progenitor lineage, IL-2 stimulates T cell differentiation; IL-4 and IL-6 stimulate differentiation of B cells. The colony-stimulating factors also enhance function and cause activation of the mature cells whose production they induce. In clinical trials, these hormones have successfully ameliorated anemia in renal failure, chronic disease, and in prematurity. They have improved pancytopenias in aplastic anemia, myelodysplastic syndromes, and congenital cytopenias, and they have hastened recovery from chemotherapy and bone marrow transplantation.
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PMID:Hematopoietic hormones: from cloning to clinic. 267 59

A complete hematologic remission was achieved in a patient with therapy-related preleukemia and transfusion-dependent pancytopenia after treatment with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). The patient remained in remission for nearly 1 year despite the discontinuation of GM-CSF treatment. Several lines of evidence suggest that normal hematopoiesis was restored after GM-CSF treatment. First, the cytogenetic anomaly, which was present before GM-CSF, completely disappeared after three cycles of treatment. Cytogenetic conversion was documented by conventional karyotypic evaluation of mitotic bone marrow cell preparations as well as by premature chromosome condensation analysis of the nonmitotic cells of bone marrow and peripheral blood. Second, the growth pattern and cycle status of bone marrow granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) progenitor cells were found to be normal during remission. Third, X chromosome-linked restriction fragment length polymorphism-methylation analysis of DNA from mononuclear cells (greater than 80% lymphocytes) and mature myeloid elements showed a polyclonal pattern. These findings suggest that restoration of hematopoiesis in this patient after GM-CSF treatment may have resulted from suppression of the abnormal clone and a selective growth advantage of normal elements.
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PMID:Stimulation of nonclonal hematopoiesis and suppression of the neoplastic clone after treatment with recombinant human granulocyte-macrophage colony-stimulating factor in a patient with therapy-related myelodysplastic syndrome. 267 13

In vitro megakaryocytic colony formation by progenitors from the bone marrow was studied in 40 myelodysplastic syndrome patients. Megakaryocytic colonies were decreased in number or absent in 30 patients; only 10 showed normal colony growth. The growth correlated to some extent with the FAB-class. Patients with normal colony formation had either RA or RARS, but also in these two FAB-types half of the patients showed reduced megakaryocytic colony formation. Only 1 out of 15 patients with RAEB or RAEBt had normal megakaryocyte growth. The patients with CMML did not show any megakaryocytic colonies. The growth of erythroid colonies was normal in 3 patients and reduced or absent in the others. All 3 with normal erythroid colony formation also showed normal megakaryocyte growth, and all patients with normal megakaryocyte colony formation also had normal granulocyte-macrophage colony growth. Granulocyte-macrophage colony and cluster formation was normal in 17 patients. Defective formation of megakaryocytic, erythroid, and granulocyte-macrophage colonies was seen in 22 patients, compatible with a defect in a pluripotent stem cell. Megakaryocytic colony formation had no obvious correlation with any specific chromosome abnormality, and the distribution of the growth patterns was almost similar in patients with a normal and those with an abnormal karyotype.
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PMID:Colony formation by megakaryocyte progenitors in myelodysplatic syndromes. 227 Oct 49

We report an autopsy case of myelodysplastic syndrome (MDS) in a 35-year-old male, who presented with pancytopenia and bleedings. Bone marrow specimens disclosed myelofibrosis and hypercellular marrow with more than 60% atypical erythroblasts in the bone marrow cells. Type I or type II blasts were less than 10% of the peripheral blood and bone marrow cells during the clinical course. At autopsy, infiltration by myeloid and erythroid cells and megakaryocytes was noted in the liver, spleen and lymph nodes. According to the FAB classification, this case might be classified into refractory anemia with excess of blasts (RAEB) or RAEB in transformation. However, the remarkable neoplastic proliferation of three haematopoietic cell lines also indicates acute myeloproliferative disorder such as acute myelofibrosis or acute panmyelosis.
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PMID:An autopsy case of myelodysplastic syndrome (MDS): diagnostic problems between MDS and the other haematopoietic disorders including acute myelofibrosis. 274 51

Splenic erythropoiesis was demonstrated by surface counting of 59Fe in 129 of 1,350 ferrokinetic studies performed over a 15 year period. These 129 studies were carried out in 108 patients, including 40 with chronic myelogenous leukemia (CML), 24 with agnogenic myeloid metaplasia (AMM), 18 with polycythemia vera (PV), six with a myelodysplastic syndrome, five with acute leukemia, three with prostate or breast carcinoma, two each with aplastic anemia or Hodgkin's disease, and one each with idiopathic thrombocythemia, multiple myeloma, chronic renal failure, or treated hypopituitarism. Splenomegaly was present in 83% of the studies and hepatomegaly in 72%. Grade II-III myelofibrosis was demonstrated in 62% of the cases. Hepatic erythropoiesis was present in 77% of the studies (only 38% in PV), and marrow erythropoiesis was undetectable in 33%. Total erythropoiesis was about twice normal (range 0.2 to 8 times normal) but was ineffective to varying degrees in 86% of the studies. Relationships between organomegaly, myelofibrosis, and extramedullary erythropoiesis, as well as differences among clinical disorders, are discussed. Differences observed between CML in chronic or blastic phase suggested that the erythroid cell line was involved in the proliferative process. It is concluded that splenic erythropoiesis 1) is encountered in a variety of clinical conditions; 2) is not necessarily associated with splenomegaly or myelofibrosis, even in the myeloproliferative disorders; 3) is part of a predominantly extramedullary (in the liver as well as in the spleen), expanded, and largely inefficient total erythropoiesis; and 4) can be evaluated in a semiquantitative manner by surface counting.
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PMID:Ferrokinetic study of splenic erythropoiesis: relationships among clinical diagnosis, myelofibrosis, splenomegaly, and extramedullary erythropoiesis. 275 9

Serum concentration of erythropoietin (Epo) has been measured by radioimmunoassay in 46 patients with myelodysplastic syndromes. There is an overall inverse relationship between the level of Epo and the degree of anaemia but a wide range of Epo response between patients with similar haemoglobin concentrations. No differences were found between the different FAB groups, but the highest Epo levels were found in those patients with erythroid hypoplasia in the bone marrow. It is suggested that the intensity of erythroid activity in the marrow, as well as the degree of anaemia, may be a factor determining serum Epo concentration.
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PMID:Circulating erythropoietin in patients with myelodysplastic syndromes. 280 75

The authors studied 35 marrow biopsies from 32 patients with rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disease, polymyositis, and psoriatic arthritis. Reasons for biopsy included cytopenia, fever of unknown origin, and malignancy. Cellularity was abnormal in 71%. Plasma cells were increased in 60% and associated with lymphoid aggregates. Immunoperoxidase stains showed polyclonal perivascular plasma cells and increased T-cells forming lymphoid aggregates. Two patients had granulomas without documented infection. Anemic patients had findings consistent with anemia of chronic disease, erythroid aplasia, hemolysis, and iron deficiency. Iron stores were variable. Platelet and granulocyte precursors were variably altered and did not predictably correlate with the presence, absence, or cause of thrombocytopenia and neutropenia. Myelodysplastic syndromes were present in two patients with rheumatoid arthritis. Osteomalacia and osteoporosis were seen, resulting from renal failure and steroids. Marrow findings are unpredictable and reflect the diverse causes of cytopenias in patients with connective tissue disorders.
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PMID:Bone marrow findings in connective tissue disease. 281 17


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