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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

3H-thymidine incorporation into normoblasts, proliferation rate of erythroid precursors and degree of intramarrow hemolysis have been studied in vitro on the bone marrow. The normal proliferation rate of normoblasts is 26 +/- 2% i.e. during 24 hours about a quarter of dividable elements of erythropoiesis is renewed. Acute blood loss increases the proliferation rate up to 57 +/- 9% but the value of 3H-thymidine incorporation into cells is not changed as compared to normal. In chronic blood loss both 3H-thymidine incorporation into dividing erythroid precursors at different stages of maturity and the rate of erythroid production are 2 to 3 times lower than normal. In healthy persons the degree of intramarrow hemolysis is 7 +/- 2% of erythroid precursors incubated for 24 hours. In iron deficiency anemia intramarrow destruction sharply increases, presenting at an average 30% of incubated nucleated elements of erythropoiesis. A type of chronic iron deficiency, which is not associated with blood loss, is described. In this type of anemia the proliferation rate of normoblasts and the degree of intramarrow hemolysis do not differ from normal values.
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PMID:Proliferative activity of erythrone and intramarrow hemolysis in iron deficiency anemias. 5 Sep 70

Congenital dyserythropoiesis with dyskeratosis is a slow, progressive, and often fatal disease in Polled Hereford calves. Affected calves have a macrocytic normochromic anemia with a mild reticulocytosis. Studies indicate that calves are hyperferremic with increased saturation of serum total iron binding capacity, which rules out iron deficiency as a cause. Other secondary causes of dyserythropoiesis, including cobalamin and folate deficiencies, are unlikely because serum cobalamin and folate levels of affected calves were normal. Virus isolation was negative, and failure to identify bovine retroviral antigens or antibodies from several calves suggested that viral agents were not involved. Bone marrow cytologic findings were similar to those in congenital hereditary dyserythropoiesis in humans and included occasional multinucleate cells, internuclear chromatin bridging between nuclei of partially divided cells, and, more frequently, irregular nuclear shapes and chromatin patterns. DNA content and cell cycle distribution of erythroid cells appeared normal, and no electrophoretic abnormalities were detected in erythrocyte membrane proteins. The Polled Hereford syndrome is similar in many ways to type I congenital dyserythropoiesis in humans and may be an appropriate biomedical model for studying erythroid proliferation during dyserythropoiesis.
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PMID:Congenital dyserythropoiesis and progressive alopecia in Polled Hereford calves: hematologic, biochemical, bone marrow cytologic, electrophoretic, and flow cytometric findings. 134 89

Chronic renal failure is almost invariably accompanied by symptomatic anemia. It has been demonstrated that the primary cause of this anemia is inadequate production of erythropoietin by the diseased kidneys. The isolation of erythropoietin, followed by the cloning and expression of the human erythropoietin gene, made possible clinical trials of rHuEPO in uremic patients. rHuEPO produced dramatic increases in the hematocrit in almost all patients treated and also ameliorated many symptoms, such as lethargy, dizziness, and poor appetite, that had long been attributed to the effect of uremic toxins. Adverse effects of treatment with rHuEPO noted in the early clinical trials included hypertension, seizures, arteriovenous fistula or shunt thrombosis, and hyperkalemia. Further study of rHuEPO has shown that many of these side effects may be no more frequent in patients receiving rHuEPO than in other uremic patients not receiving rHuEPO. Reduction of the rHuEPO dosage and subcutaneous administration produce less rapid increases in the hematocrit and may lessen the incidence and severity of these side effects. rHuEPO therapy places great demands on both the body's iron stores and the capacity to rapidly transfer iron from storage sites to the erythroid progenitor cells. Thus, almost all patients treated with rHuEPO become iron deficient and require oral or parenteral iron replacement. Response to rHuEPO in uremic patients is diminished if the anemia is complicated by iron deficiency, inflammatory disorders, aluminum overload, or deficiency of folate or vitamin B12. rHuEPO therapy is safe and effective in the treatment of the anemia of chronic renal failure. The use of rHuEPO leads to enhanced quality of life and eliminates the need for red cell transfusions. In addition to hemodialysis patients, predialysis patients and those on CAPD benefit from and are candidates for rHuEPO therapy.
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PMID:Anemia of renal failure. Use of erythropoietin. 157 66

Anaemia in rheumatoid arthritis (RA) is a common and debilitating complication. The most common causes of this anaemia are iron deficiency and anaemia of chronic disease. Investigations have suggested that interleukin 1 (IL-1) or tumour necrosis factor (TNF), or both, from monocytes associated with chronic inflammation are responsible for the anaemia of chronic disease. On bone marrow examination anaemia of chronic disease is characterised by the diversion of iron from the erythropoietic compartment into marrow macrophages. This phenomenon is termed failure of iron utilisation. In this study, CFU-E (colony forming unit erythroid; late red cell precursors) and BFU-E (burst forming unit erythroid; early red cell precursors) stem cells were cultured from 10 normal marrow samples and 12 marrow samples from patients with RA with iron deficiency anaemia and 10 samples from patients with RA with failure of iron utilisation. All patients with RA were anaemic (haemoglobin less than 100 g/l), Potential accessory or inhibitory cells of erythropoiesis (CD4, CD8, or CD14 positive cells) were removed before culture. Control marrow samples were studied in a similar manner. Normal marrow samples yielded 377 (17) CFU-E and 133 (6) BFU-E (mean (SD)) colonies for each 2 x 10(5) light density cells plated. CD4 ablation caused reductions of 62 and 100% in CFU-E and BFU-E colonies respectively. CD14 removal resulted in considerable but lesser reductions of 46% for CFU-E and 25% for BFU-E. In both groups of patients with RA, CFU-E colony numbers were significantly lower than those seen in normal control subjects, 293 (17) for patients with iron deficiency anaemia and 242 (35) for patients with failure of iron utilisation. BFU-E colony numbers were 102 (13) and 108 (20) respectively. In patients with RA, CD4 removal caused a significantly greater loss of CFU-E colonies compared with normal control subjects. Cytolysis of CD14 positive cells caused a reduction in CFU-E colonies in the two RA groups which was similar to that seen in normal subjects. In conclusion, patients with RA seem to have fewer CFU-E progenitors but essentially normal numbers of BFU-E stem cells. Our data suggest a stimulatory role for marrow CD4 and CD14 cells in erythropoiesis in patients with RA. Monocytes-macrophages (CD14 positive) are known to be producers of IL-1 or TNF, or both, however, the predicted increase in the CFU-E colonies on removal of CD14 cells is not seen. Therefore, if IL-1 or TNF, or both, are responsible for the impairment of erythropoiesis in patients with RA, marrow macrophages are unlikely to be the source. Moreover, these results indicate the probability of erythropoietin resistance on the basis of diminished CFU-E colony formation in patients with RA.
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PMID:Anaemia of chronic disease in rheumatoid arthritis: effect of the blunted response to erythropoietin and of interleukin 1 production by marrow macrophages. 161 58

In 4 years (1984-1987), 183 bone marrow examinations were performed on 155 human immunodeficiency virus (HIV) antibody positive patients. One hundred and fifty three had category IV AIDS. One-third of the marrows yielded specific information. This included opportunistic infection, in particular Mycobacterium Avium Intracellulare Complex (MAI) (24%), malignancy (4%), consistent with ITP (9%) and iron deficiency (1%). In the remaining two thirds of the bone marrows the most frequent non-specific abnormalities were dyserythropoiesis, erythroid hypoplasia, reticuloendothelial iron block, granulomas, lymphoid aggregates, plasmacytosis and histiocytosis. Common peripheral blood findings were anemia, lymphopenia, anisocytosis, rouleaux and atypical lymphocytes. Peripheral blood and bone marrow examinations on 16 patients on AZT are included. These patients have more pronounced blood and bone marrow abnormalities. The causes of these abnormalities are multifactorial and include low T4 levels, severe viral and other infections and therapy with marrow toxic drugs.
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PMID:Peripheral blood and bone marrow findings in patients with acquired immune deficiency syndrome. 209 Oct 4

Principal concepts concerning the anemia of RA are summarized in Tables 7 and 8. These concepts have been validated by our analysis of 93 anemic RA patients and by our review of the literature. The fact that anemia in RA may have one or more etiologies, occasionally in the same patient, mandates a reasoned approach to the analysis of anemia in every RA patient in whom it may occur. In particular, iron deficiency is common and determination of bone marrow iron content via an aspirate may be required for a definitive diagnosis. In those RA patients with anemia of chronic disease, the best therapy remains control of the underlying disease, most commonly with second line drugs and/or corticosteroids. The place for recombinant erythropoietin in the therapy of this anemia has not been defined; one specific role for erythropoietin may be in the preparation of RA patients for elective surgery, particularly hip arthroplasty, where correction of the anemia may either obviate the need for transfusion or may allow for donation of blood for purposes of autologous transfusion perioperatively. The pathogenesis of the anemia of chronic disease, as seen in RA anemia, is not completely understood. Inflammatory mediators, particularly the cytokines, appear to be important factors in the impairment of erythropoiesis. The mechanism by which these cytokines impair erythroid progenitor growth and hemoglobin production in developing erythrocytes is an important area for future study.
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PMID:The pathogenesis of anemia in rheumatoid arthritis: a clinical and laboratory analysis. 218 69

In order to clarify possible factors responsible for varying responses in uremic patients treated with recombinant human erythropoietin (rHuEPO), we determined the inhibitory effects of ten uremic sera on the erythroid progenitors (CFU-E) and erythroid bursts (BFU-E). We also measured plasma EPO titers, Fe, UIBC, ferritin, PTH-C, beta 2-microglobulin, and aluminum in all ten patients. The inhibitor of CFU-E but not BFU-E, was present in the serum of the single anemic patient whose recovery took longer after the administration of rHuEPO. He did not have such conditions as iron deficiency, excess of aluminum, or chronic inflammation. The remaining patients, who had no CFU-E or BFU-E inhibitors, were good responders to rHuEPO. In none of ten patients were there inhibitors of granulocyte-macrophage progenitors (CFU-GM) or any differences in the other parameters. Although the inhibitory factor of CFU-E can be overcome with a larger dose, its prior determination may be useful to set out minimal effective dose of EPO treatment.
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PMID:The inhibitory factors of hematopoiesis in chronic hemodialysis patients treated with recombinant human erythropoietin. 224 92

We have used the monoclonal antibodies 2A4 (specific for the H subunit of human ferritin) and LO3 (specific for the L subunit) for immunocytochemical detection of ferritin in bone marrow and peripheral blood cells from normal subjects and patients with various haematological disorders. Formalin-fixed slides were stained by the immunoalkaline phosphatase procedure (APAAP). In normal subjects, ferritin could be found only in bone marrow smears and appeared to be largely confined to erythroid precursors and reticuloendothelial cells. The more immature erythroid precursors contained higher concentrations of cellular ferritin. Although evaluation could be only semiquantitative, erythroblast ferritin appeared to be more reactive with the monoclonal 2A4 (15 +/- 7% positive erythroblasts) than with the monoclonal LO3 (6 +/- 5% positive erythroblasts), indicating that H-type ferritin was predominant, particularly in proerythroblasts and basophilic erythroblasts. By contrast, the ferritin present in reticuloendothelial cells appeared to be predominantly of L-type. Patients with iron deficiency showed low levels of positive erythroblast, whereas the reverse was true in patients with transfusional iron overload. Intense positivity for reticuloendothelial cell ferritin was found in patients with anaemia of chronic disease. In myelodysplastic syndromes and acute myeloid leukaemia (AML), ferritin positivity was generally very strong at any stage of erythroblast development, particularly with the monoclonal antibody 2A4. Perls-positive perinuclear granules of ring sideroblasts were not stained, confirming that mitochondrial iron deposition is not in the form of ferritin. In AML and myelodysplastic syndromes with excess of blasts, ferritin could be detected also in immature myeloid cells. These data indicate that: (a) in normal conditions ferritin is mainly expressed in red cell precursors and reticuloendothelial cells, and this is in keeping with the peculiar role of these cells in iron metabolism; (b) abnormal cell ferritin contents can be observed in both iron overload and malignancy.
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PMID:Immunocytochemical detection of ferritin in human bone marrow and peripheral blood cells using monoclonal antibodies specific for the H and L subunit. 226 53

Erythroid colony growth in the presence and absence of erythropoietin was compared in 23 patients with primary proliferative polycythaemia (PPP), nine with idiopathic erythrocytosis, 10 with secondary polycythaemia, 15 with pseudopolycythaemia and in 76 normal subjects. Erythroid colonies growing without erythropoietin stimulation (endogenous erythroid colonies) from peripheral blood (BFU-E) were found in 20 of 22 patients with PPP and in two of seven with idiopathic erythrocytosis. None was found in secondary polycythaemia, pseudopolycythaemia, or in normal subjects. Small numbers of endogenous colony forming units-erythroid (CFU-E) (though not BFU-E) were cultured from the bone marrow of three of 24 normal subjects, suggesting that peripheral blood cultures provide a more specific indicator of clonal erythropoiesis. Peripheral blood endogenous erythroid colony growth is an effective and convenient means of distinguishing patients with clonal erythrocytosis and may be of particular value when iron deficiency obscures the diagnosis of PPP on conventional criteria.
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PMID:Erythroid colony growth from peripheral blood and bone marrow in polycythaemia. 226 65

Intact transferrin receptor molecules complexed with transferrin were found in human plasma. The concentration of receptors was determined by an enzyme-linked immunosorbent assay that uses polyclonal antibodies. The mean concentration of 8,279 micrograms/L in 56 normal adults appears to be unrelated to age or sex. Additional receptor measurements were performed on plasmas from 260 subjects with erythropoietic disorders. Decreased concentration of plasma receptors was found in patients with erythroid hypoplasia and increased numbers in those with erythroid hyperplasia. Ferrokinetic measurements of erythropoiesis were compared with numbers of receptors in 148 subjects, and a close correlation was found (r = .86). Both sets of values, measured in different conditions and expressed in relation to normal, were consistent with expected values. Receptor values were unproportionally increased only in conditions of iron deficiency. It is concluded that plasma receptors have a constant relationship to tissue receptors, and their number in most instances reflects the rate of erythropoiesis.
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PMID:Intact transferrin receptors in human plasma and their relation to erythropoiesis. 229 84


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