Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The myeloproliferative disorders, including polycythaemia rubra vera, arise as a result of a single-cell mutation. A characteristic of the abnormal haemopoietic clone is that it can form erythroid colonies in vitro in the absence of added erythropoietin. Such endogenous erythroid clones were consistently found in two of seven patients with peripheral vascular disease. These two patients had mean platelet counts of 600 X 10(9)/l and 630 X 10(9)/l. Culture of blood and bone-marrow cells from patients with raised platelet counts secondary to a variety of other disorders failed to yield such colonies. The presence of endogenous erythroid clones provides early evidence of a myeloproliferative disorder.
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PMID:Formes frustes in myeloproliferative disorders. Identification by the growth of an endogenous erythroid clone in vitro in patients with arterial vascular disease. 611 13

The bone marrow biopsy specimens of 35 patients with benign and malignant erythroid hyperplasias were examined for the presence of hemoglobin A, hemoglobin F, muramidase (lysozyme), and transferrin, using an indirect immunoperoxidase method (PAP) on Zenker's-fixed paraffin-embedded bone marrow biopsy specimens and particles. Five cases of each of the following entities were studied: erythroleukemia and erythremic myelosis, acute granulocytic leukemia with maturation (FAB M2), polycythemia rubra vera, myeloproliferative syndrome in childhood, megaloblastic anemia (B12 and folate deficiency), erythroid hyperplasia (regenerating bone marrow and hemolytic anemia), and Ph' chromosome positive chronic granulocytic leukemia. Hemoglobin A was present in both the early and late erythroid precursors in all conditions. Hemoglobin F was the predominant hemoglobin in early erythroblasts of pernicious anemia and in both early and late erythroid elements in erythroleukemia and erythremic myelosis. Small quantities of hemoglobin F were present in a few isolated clusters in other conditions. Staining for hemoglobin F may be useful in identifying immature erythroid precursors and in distinguishing some cases of dysplastic erythroid hyperplasia from neoplasia. Additionally, these findings suggest that the maturational switch in hemoglobin synthesis operates with distinct pathways under different conditions.
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PMID:An immunohistochemical study of hemoglobin A, hemoglobin F, muramidase, and transferrin in erythroid hyperplasia and neoplasia. 619 99

Four adolescents with polycythaemia are described where symptoms typical of the disease had already existed in childhood. Three patients fulfilled the criteria of a polycythaemia vera. In one female patient the possibility of familial erythrocytosis is discussed. Polycythaemia vera mononuclear cells formed erythroid colonies in cultures in the absence of erythropoietin. The patients were phlebotomized to maintain haematocrit readings of 40 to 45%. No case has yet progressed to myeloid metaplasia or acute leukaemia.
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PMID:Primary polycythaemia in childhood and adolescence. 620 Apr 7

Mononuclear cells from peripheral blood of six patients with polycythemia after kidney transplantation were studied in methyl cellulose cultures using fetal calf serum with and without adding erythropoietin. Parallel tests were run with "synthetic medium". The data obtained were compared to those of patients with polycythemia vera and normal subjects. The erythropoietin independent proliferation in synthetic medium typical for polycythemia vera could not be found in patients with renal grafts. However, in the preparations with fetal calf serum without erythropoietin, a formation of erythroid colonies could be detected suggesting an increased sensitivity or proliferation of erythropoietically determined stem cells in patients with transplanted kidneys.
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PMID:Studies in polycythemia after kidney transplantation. 635 9

Basic ferritin content of red cells has been evaluated with a simplified assay in subjects with various erythroid disorders. In 39 patients with iron deficiency anemia, red cell ferritin was significantly reduced compared with that of normal individuals. Thirty percent of these patients had low normal red cell ferritin content and the MCV for this group was significantly higher than that of patients with reduced red cell ferritin. The mean red cell ferritin of 30 subjects with the anemia of chronic disease was significantly reduced and patients in this group with normal red cell ferritin had higher plasma ferritin levels. In 14 patients with polycythemia vera, the mean red cell ferritin was significantly reduced and showed a positive correlation with the hemoglobin level and percent transferrin saturation. The red cell ferritin content of 9 individuals with acquired immune hemolytic anemia and 10 with acquired sideroblastic anemia was significantly elevated and, in subjects with immune hemolysis, showed a positive correlation with the reticulocyte count. These findings suggest a lack of discriminatory function for red cell ferritin in iron deficiency anemia and anemia of chronic disease. Evaluation of this parameter in the individual patient should take into account the presence of reticulocytosis.
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PMID:Basic ferritin content of red cells of patients with anemia and polycythemia vera. 652 7

We have studied the behavior in culture of circulating restricted hemopoietic progenitor cells from patients with idiopathic myelofibrosis (IMF), polycythemia vera (PV), and essential thrombocytopenia (ET). We have found differences in circulating granulocyte-macrophage, erythroid, and megakaryocytic progenitors that appear to be specific for these chronic myeloproliferative disorders. In IMF, most affected were granulocyte-macrophage progenitor cells (CFU-C), which circulated in increased numbers and were heterogeneous in their sensitivity to the regulatory factor(s) present in phytohemagglutinin (PHA) stimulated T-lymphocyte conditioned medium (CM). Most CFU-C were either highly sensitive to, or independent from, stimulatory factors, while others showed normal sensitivity. In some IMF patients, circulating megakaryocytic progenitors (CFU-M) were present that were capable of giving rise to colonies in the absence of added CM or erythropoietin (EPO). In PV, we confirmed the presence of circulating erythroid progenitor cells that give rise to colonies in culture without the addition of EPO. The number of circulating CFU-C was normal and they responded normally to CM. In ET, failure to detect 7-day circulating restricted progenitor cells was a common observation; the level of other circulating restricted progenitors was in the low normal range. Thus, despite certain common features, including a primary lesion at the level of the pluripotential hemopoietic stem cell, the myeloproliferative disorders differ with respect to the behavior in culture of their circulating restricted progenitor cells. These results have led us to postulate a second regulatory lesion in the pluripotential stem cell that differs in these disorders and is expressed at the level of the respective restricted progenitor cells.
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PMID:Differences among myeloproliferative disorders in the behavior of their restricted progenitor cells in culture. 660 77

Peripheral blood burst forming units-erythroid (BFU-E) were measured by the plasma clot cell culture technique in patients with the various subtypes of polycythaemia and compared to normal. 10 patients with active polycythaemia rubra vera (PRV) were found to have a mean BFU-E level of 48 +/- 15.8 (SEM) per 5 X 10(5) cultured cells which was significantly different from normals (4 +/- 1.1, P less than 0.02), patients with controlled PRV (7 +/- 1.6, P less than 0.025), secondary polycythaemia (1 +/- 0.3, P less than 0.015) and relative polycythaemia (0, P less than 0.015). Burst forming units were found to fall to normal levels in patients with PRV with appropriate disease control and then to rise again in patients untreated for more than 18 months. Clinical aspects. Measurement of BFU-E levels from the peripheral blood could provide a useful adjunct from an accessible source in the differential diagnosis of polycythaemia as well as being of use in serial monitoring of patients with PRV.
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PMID:An analysis of peripheral blood burst forming units-erythroid in the polycythaemic states. 662 75

Erythroid colony formation from the bone marrow and blood of 30 patients with erythrocytosis has been studied. Seventeen patients formed spontaneous erythroid colonies. They included patients with polycythaemia vera (PV) and 4 patients who did not quite fulfil the Polycythemia Vera Study Group criteria for PV, but had suggestive evidence of a myeloproliferative disorder. Thirteen patients did not form spontaneous colonies. They included patients with secondary polycythaemia, patients with normal total red cell volume and patients with absolute pure erythrocytosis of unknown origin. All patients with PV, and none with secondary polycythaemias, had spontaneous erythroid colony formation. Three of 4 untreated and 2 of 9 treated PV patients had increased number of CFU-E colonies in bone marrow. From these results it can be concluded that erythroid progenitor cell culture is a useful differential diagnostic method in erythrocytosis patients who cannot be classified clinically under PV or secondary polycythaemias.
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PMID:Spontaneous erythroid colony formation in erythrocytosis. 662 46

Erythropoietic progenitors from peripheral blood of normal individuals or patients with polycythemia vera (PV) were cultured in methylcellulose medium containing 2.5 U/ml of erythropoietin (Ep). After 7-9 days, colonies considered to be early stage large bursts were individually removed, resuspended in a small volume of fresh methylcellulose medium, and then divided between 2 dishes. To one of these secondary cultures, sufficient Ep was added to bring the concentration of Ep up to approximately 3 U/ml. To the other was added an equal volume of medium but no Ep. The final concentration of Ep in these cultures was determined to be less than 0.01 U/ml. Nine days later, both types of secondary cultures were scored for the presence of colonies containing 8 or more hemoglobinized erythroblasts. Of 90 primary colonies from 3 normal individuals assessed in this way, 59 gave secondary erythroid colonies in the high Ep cultures, while none gave secondary erythroid colonies in the low Ep cultures. Additional control experiments in which primary colonies from normal individuals were divided into duplicate high Ep cultures showed that on average, the procedure used divided primary colonies equally. Of 109 primary colonies from 5 PV patients that yielded secondary erythroid colonies in the high Ep cultures, 21 yielded no secondary erythroid colonies in the low Ep cultures. The other 88 yielded erythroid colonies in both, but the secondary colonies in the low Ep cultures were consistently smaller in size and significantly fewer in number. Similar results were obtained when primary colonies were generated in cultures to which no Ep was added. These findings indicate that primitive BFU-E in patients with PV can be subdivided into 2 populations: a minor population restricted to the production of erythroid colony-forming cells (Ep-dependent progenitors) that require Ep for their detection, and a major population that is not restricted in this way. In addition, these experiments show that most of the primitive BFU-E that generate Ep-independent progenitors also produce significant numbers of cells that are Ep-dependent.
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PMID:Individual BFU-E in polycythemia vera produce both erythropoietin dependent and independent progeny. 683 Oct 48

Peripheral blood mononuclear cells from five patients with polycythemia vera (P. vera) and three with other polycythemias were cultured in a methylcellulose system. Colony-forming unit-erythroid (CFU-E) colonies appeared after seven days in the absence of added erythropoietin (Ep) in all P. vera cultures. A pattern of growth similar to the one seen for P. vera patients occurred in the culture from a patient in whom that disease was suspected. In the cultures from two of the patients with other polycythemias, erythroid colonies did not appear even in the presence of Ep. These findings emphasize the potential value of culturing peripheral blood for CFU-E colonies in diagnosing polycythemia vera.
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PMID:Diagnostic use of CFU-E formation from peripheral blood in polycythemia vera. 683 14


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