Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A panel of monoclonal antibodies recognizing myeloid cell surface differentiation-associated antigens was used to study the peripheral blood myeloid population of 23 patients with myelodysplastic syndromes (MDS) and 23 controls. A marker for immaturity, defined by the presence of the antigen recognized by the My9 antibody, was found to persist on the surface of mature neutrophils in a subgroup of MDS patients. Abnormal My9 positivity was concentrated primarily, but not exclusively, in previously described morphologically defined subgroups of MDS patients considered to be at highest risk for leukemic conversion. Longitudinal study of a larger number of patients will be required to test the hypothesis that abnormal persistence of My9 may have prognostic significance.
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PMID:Myeloid cell surface phenotype in myelodysplasia: evidence for abnormal persistence of an early myeloid differentiation antigen. 371 45

The myelodysplastic syndromes represent a prognostically diverse group of disorders. Their study has recently been facilitated by the classification proposed by the French-American-British (FAB) Cooperative Group. Using this scheme it is now possible to define more precisely their natural history and clinical relationship to acute leukaemia. Using the longitudinal case control technique, we reviewed the clinical data and morphology of 69 patients (all elderly males) with chronic irreversible haematological cytopenia and dysplasia. Applying FAB criteria we found: refractory anaemia (RA) in 43%; sideroblastic anaemia (RA-S) in 33%; refractory anaemia with excess blasts (RAEB) in 13%; RAEB in transformation (RAEB-T) in 9% and chronic myelomonocytic leukaemia (CMML) in 1%. The median survival for the entire group was 27 months (RA, 52; RA-S, 29; RAEB, 12; RAEB-T 11; and CMML, 2 months). Short survival was predicted by transfusion requirement and other manifestations of severe cytopenia, as well as by myeloid immaturity. The presence or absence of sideroblastosis did not correlate with survival. Acute leukaemia developed in only eight patients (12%), six of whom initially had RA. Leukaemic transformation was not predicted by progressive cytological immaturity. This study demonstrates that even in the absence of leukaemic transformation, chronic myelodysplasia is a lethal haematological disorder.
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PMID:Chronic myelodysplastic syndrome: short survival with or without evolution to acute leukaemia. 660 68

Cytogenetic analysis of bone marrow cells of a 63-year-old male Caucasian patient with polycythemia vera (PV) who developed anemia, thrombocytopenia, and increased granulocytic immaturity revealed a 47, X,der(Y) t(Y;1)(q12;q12),+9 karyotype. The breakpoint in chromosome 1 appeared to map to q12 and not to q21, as has been described in previous reports without FISH confirmation. In the 4 years before this transition the patient was polycythemic and, accordingly, treated with phlebotomy and three short courses of busulfan. The cytogenetic picture observed has been described before in seven patients: three with PV, three with myelodysplasia, and one with Fanconi anemia. In 5/7 cases, like in our patient, the abnormality was observed during transition of the disease into either myelodysplasia or AML.
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PMID:Derivative (y)t(Y;1)(q12;q12),+9 in a patient with polycythemia vera during transition into myelodysplasia. 863 Sep 87

The Fgr protein-tyrosine kinase, p55(c-fgr), is specifically expressed and functions in cells of myelomonocytic lineages. We examined levels of expression and enzymatic activity of p55(c-fgr) peripheral blood neutrophils of patients with myelodysplastic syndromes (MDS) and chronic myelogenous leukemia (CML) by comparison with those of normal individuals. While neutrophils of eight normal subjects gave uniform results, the specific enzymatic activity of p55(c-fgr), a ratio of the total kinase activity versus the protein level was reduced in seven out of eight patients with MDS and all of five patients with CML. The specific kinase activity of p55(c-fgr) correlated significantly with the activity of neutrophil alkaline phosphatase (NAP) which has been considered to be a marker of neutrophil maturity (r=0.568, P<0.01). The reduced activity of this tyrosine kinase was considered to be a biological parameter for immaturity and to reflect dysfunction of neutrophils of patients with MDS and with CML.
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PMID:Activity of Fgr protein-tyrosine kinase is reduced in neutrophils of patients with myelodysplastic syndromes and chronic myelogenous leukemia. 863 16

A 16-year-old boy developed bronchiolitis obliterans (BO) 10 years after BMT for myelodysplastic syndrome. Although the patient complained of almost no dyspnea on exertion, he had mild hypercapnea with a markedly reduced forced expiratory volume of 0.32 l. Chest X-rays showed occasional bilateral minimal pneumothoraces, which is in accordance with the existence of multiple small bullae found on the pleural surface at video-assisted thoracic surgery. Histologic examination of the biopsied lung revealed BO. This case indicates that BO in adolescence following BMT and possible chronic GVHD may be masked because of lung immaturity at BMT, and BO after BMT may be associated with multiple pleural bullae.
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PMID:Bilateral pneumothoraces with multiple bullae in a patient with asymptomatic bronchiolitis obliterans 10 years after bone marrow transplantation. 1023 Nov 47

A case of a 66-year-old Japanese man developed therapy-related megakaryoblastic leukemia with pituitary involvement after chemotherapy for non-Hodgkin's lymphoma. Alkylating agents had been administered for the treatment of non-Hodgkin's lymphoma and 6 years later, megakaryoblastic leukemia with myelofibrosis and myelodysplasia developed. The blast cells expressed CD41, and immature antigens also. These findings were compatible with therapy-related megakaryoblastic leukemia. An autopsy revealed blast-cell infiltration into multiple organs including the posterior pituitary lobe. Therapy-related megakaryoblastic leukemia is very rare, and pituitary involvement may be associated with immaturity of blast cells.
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PMID:Therapy-related megakaryoblastic leukemia with pituitary involvement following treatment for non-Hodgkin's lymphoma. 1056 55

A dog with myelodysplastic syndrome had microcytic hypochromic anemia, with siderocytes, poikilocytosis, hypersegmented neutrophils and giant platelets in peripheral blood. In bone marrow, the erythroid series showed immaturity, asynchronous maturation and sideroblasts. Dysgranulopoiesis and dysthrombopoiesis also were present, and hemosiderin was increased. Serum iron concentration was high, and both iron deficiency and lead toxicity were excluded as the cause of dyscrasia. This case represents a unique variant of myelodysplastic syndrome, best described as sideroblastic myelodysplasia. We propose the terms dyserythropoiesis, sideroblastic dyserythropoiesis, dyserythropoiesis with excess blasts, myelodysplasia and sideroblastic myelodysplasia to describe and categorize myelodysplastic syndromes in dogs.
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PMID:Myelodysplastic syndrome with sideroblastic differentiation in a dog. 1207 26

Knowledge of the blast phenotype in myelodysplastic syndrome (MDS) would be valuable, as in other malignancies, but remains sparse. This is mainly because MDS blasts are a minor population in clinical samples, making analysis difficult. Thus, for this blast phenotype study, we prepared blast-rich specimens (using a new density centrifugation reagent for harvesting blasts) from blood and marrow samples of 95 patients with various MDS subtypes and 21 patients with acute leukemia transformed from MDS (AL-MDS). Flow cytometry revealed that a high proportion of the enriched blast cells (EBCs) from almost all patients showed an immunophenotype of committed myeloid precursors (CD34(+)CD38(+)HLA-DR(+)CD13(+)CD33(+)), regardless of the disease subtype. The cytochemical reaction for myeloperoxidase was negative in 58% of the cases. Thus, the EBC phenotype is more immature in MDS than in de novo acute myeloid leukemia. MDS EBCs often coexpressed stem cell antigens and late-stage myeloid antigens asynchronously, but rarely expressed T- and B-lymphoid cell-specific antigens. Markers for myeloid cell maturation (CD10 and CD15) were more prevalent on EBCs from low-risk MDS (refractory anemia [RA] and RA with ringed sideroblasts), whereas markers for myeloid cell immaturity (CD7 and CD117) were more prevalent on EBCs from high-risk MDS (chronic myelomonocytic leukemia, RA with excess blasts [RAEB], and RAEB in transformation) and AL-MDS. A shift to a more immature phenotype of EBCs, accompanying disease progression, was also documented by sequential phenotyping of the same patients. Further, CD7 positivity of EBCs was an independent variable for a poor prognosis in MDS. These data represent new, valuable information regarding MDS.
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PMID:Clinical significance of phenotypic features of blasts in patients with myelodysplastic syndrome. 1239 41

AML1 (RUNX1) encodes a DNA-binding subunit of the CBF transcription factor family and is required for the establishment of definitive hematopoiesis. AML1 is one of the most frequently mutated genes associated with human acute leukemia, suggesting that genetic alterations of the gene contribute to leukemogenesis. Here, we report the analysis of mice carrying conditional AML1 knockout alleles that were inactivated using the Cre/loxP system. AML1 was deleted in adult mice by inducing Cre activity to replicate AML1 deletions found in human MDS, familial platelet disorder and rare de novo human AML. At a latency of 2 months after induction, the thymus was reduced in size and frequently populated by immature double negative thymocytes, indicating defective T-lymphocyte maturation, resulting in lymphatic diseases with 50% penetrance, including atypical hyperplasia and thymic lymphoma. Metastatic lymphomas to the liver and the meninges were observed. Mice also developed splenomegaly with an expansion of the myeloid compartment. Increased Howell-Jolly body counts indicated splenic hypofunction. Thrombocytopenia occurred due to immaturity of mini-megakaryocytes in the bone marrow. Together with mild lymphocytopenia in the peripheral blood and increased fractions of immature cells in the bone marrow, AML1 deficient mice display features of a myelodysplastic syndrome, suggesting a preleukemic state.
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PMID:AML1 deletion in adult mice causes splenomegaly and lymphomas. 1624 65

This study was aimed at exploring the immunophenotypic features of blasts in patients with myelodysplastic syndromes (MDS). Four-color flow cytometry using conventional and secondary gating strategies was used to immunophenotype blasts and the CD34 positive cells in bone marrow nucleated cells of 29 patients with MDS. The results showed: (1) with progression of MDS from RA/RAS, RAEB to RAEB-T, the proportion of CD34(+) cells were gradually increased from 8.0%, 46.4% to 76.8% (P < 0.05); (2) using CD45 vs SSC gating strategy, with the transformation of RA/RAS, RAEB to RAEB-T, the expression of HLA-DR, CD13, CD33, CD117 were also gradually increased (P < 0.05), and the expression of CD15 was gradually decreased (P < 0.05); (3) using CD45 vs CD34 gating strategy, the expression of HLA-DR, CD13, CD33, CD117 on blasts were higher by secondary gating method than those by conventional gating (P < 0.05). However, there were no significant difference (P > 0.05) in the expression of above-mentioned antigens on CD34(+) cells among different MDS subtypes. It is concluded that conventional gating method can reflect MDS progression from RA/RAS, RAEB to RAEB-T, and secondary gating strategy may accurately reflect the biological features of blasts in MDS. Abnormal expression of CD34 is related to the immaturity level and heterogeneity of blast cells, which is beneficial to the diagnosis of clinically suspected MDS incapable of diagnosing with morphology and cytogenetics.
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PMID:[Four-color flow cytometric immunophenotypic features of blasts in myelodysplastic syndromes]. 1658 91


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