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

Hemin allows maximal protein synthesis in intact rabbit reticulocytes and their cell-free lysate preparations by retarding the formation of a translational repressor (HCR) found in the postribosomal supernate. In order to evaluate the role of HCR in the pathogenesis of hypochromic anemias, HCR was isolated and partially purified from intact rabbit reticulocytes incubated in vitro with either 0.1 mM alpha,alpha-dipyridyl (an iron-chelating agent) or 0.1 M ethanol. Both of these agents inhibit reticulocyte protein synthesis. Hemin (50 muM) protects against the inhibition by both agents. A ferrous iron-transferrin mixture, however, protects only against alpha,alpha-dipyridyl. Both alpha,alpha-dipyridyl and ethanol inhibit heme synthesis before the time that protein synthesis is affected, while neither lowers either ATP or GSH levels. These results indicate that while both agents inhibit heme synthesis, alpha,alpha-dipyridyl does so by inducing iron deficiency while ethanol works at a non-iron-requiring step. When HCR was isolated from intact cells and assayed in the reticulocyte cell-free systems, plus and minus hemin, premature appearance of HCR was found in cells incubated in vitro with alpha,alpha-dipyridyl or ethanol. When hemin was present in the intact cell incubation, the appearance of HCR was retarded. The HCR from alpha,alpha-dipyridyl ethanol-treated cells was partially purified and eluted at the same location on a Sephadex G-200 column (molecular weight approximately 3 x 10(5)) as that from postribosomal supernates incubated minus hemin. In addition rabbits with phenylhydrazine-induced hemolytic anemia were given intravenous ethanol in vivo at a dose of 0.4 ml/kg. This concentration of alcohol resulted in an inhibition of the rate of heme synthesis and protein synthesis as well as an acceleration of HCR formation in reticulocytes. The HCR from these in vivo treated rabbits was isolated, partially purified, and assayed in an identical fashion as the in vitro experiments. These in vivo experiments further support the physiological and pathophysiological role of HCR in reticulocytes. On the basis of these results a model for a role of HCR in some of the hypochromic anemias is proposed. In iron deficiency or chronic disease (where iron is not available to the erythroblast for heme synthesis) HCR appears prematurely and inhibits protein synthesis. When heme synthesis is inhibited by ethanol but there is sufficient intracellular iron, HCR appears prematurely and inhibits protein synthesis, iron accumulates in the erythroblast, and the end result is sideroblastic anemia.
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PMID:A rabbit reticulocyte model for the role of hemin-controlled repressor in hypochromic anemias. 0 17

The amount and effectiveness of erythropoiesis was measured using 59Fe in 10 patients with the anaemia of chronic disease and in 10 iron deficient patients with a comparable degree of anaemia. In both conditions the anaemia was the result of the failure of the marrow to compensate for a modest degree of peripheral haemolysis but ineffective erythropoiesis was significantly greater in iron deficiency than in chronic disease. The results suggest that although the peripheral blood picture is similar in both conditions the anaemia of chronic disease cannot be attributed simply to iron deficient erythropoiesis.
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PMID:Erythropoiesis in the anaemia of chronic disease. 30 42

Iron should not be prescribed to middle-aged men or older women with anaemia unless the possibility that the iron deficiency is caused by a gastrointestinal tumour has been considered. Thus the prescribing of iron to elderly people was investigated by studying four different prescription statistics and by reviewing records. Over one in 10 women aged over 65 were prescribed iron tablets. Men and women in the oldest age groups were prescribed iron most frequently. The reasons for prescribing iron were examined at a rural health centre. Out of 327 records of patients who were prescribed iron during 1975, 157 were randomly selected and reviewed. Only 18 out of 48 (38%) patients aged 45-75 (men) and 55-75 (women) and 29 out of 109 (27%) aged over 75 years had probable or possible iron-deficiency anaemia as established from the records. Only nine (19%) of the younger patients had a plausible reason for the anaemia other than a bleeding tumour. Ten (9%) of the older patients were considered to be inoperable cases. Thus, according to the records, only 18 (17%) of the patients over 75 years and nine (19%) of those in the younger age group have been prescribed iron. About 70% of all the patients were considered not to have iron deficiency; 7% had had iron deficiency previously, and 20% probably had anaemia as a result of chronic disease; for 43% no real reason for the iron prescription could be found in the record. Thus it is concluded that iron is overprescribed in Sweden, particularly for elderly people. It should not be prescribed until the possibility of a bleeding gastrointestinal tumour has been excluded.
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PMID:Overprescribing iron tablets to elderly people in Sweden. 31 8

(1) Brief introduction to iron metabolism and the biochemistry of ferritin. (2) Early studies of circulating ferritin. (3) Methods for measuring serum ferritin concentrations -- immunoradiometric, radioimmuno- and enzyme-linked immuno assays based on liver or spleen ferritin -- an evaluation of these techniques. (4) Serum ferritin concentrations in normal subjects -- definition of normality -- relationship between storage iron and serum ferritin concentrations -- changes during development from birth to old age -- iron deficiency -- variability of serum ferritin concentration -- evaluation of use of ferritin assay for assessment of storage iron levels. (5) Serum ferritin concentrations in disease -- hemochromatosis -- secondary iron overload -- liver damage -- infection and chronic disease -- cancer. (6) Assay of serum ferritin with antibodies to ferritins other than liver or spleen -- ferritinemia and cancer. (7) Properties of serum ferritin -- molecular weight -- iron content -- isoelectric focusing patterns -- carbohydrate content -- immunological properties. (8) Physiology of circulating ferritin -- release of ferritin from tissues -- origin of circulating ferritin -- clearance from the plasma -- iron and protein turnover. (9) Summary -- factors influencing serum ferritin concentrations and clinical use of ferritin estimations.
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PMID:Serum ferritin. 37 39

When the mean corpuscular volume is normal in an anemic patient, examination of a blood smear becomes of paramount importance. When the RBCs are normochronic, normocytic, and nonpoikilocytic, the reticulocyte count determines the line of investigation. When the count is increased, either hemorrhage or hemolysis is present. When the count is not increased (ie, normal or low), the differential diagnosis includes anemias due to iron deficiency, chronic disease, renal disease, hemodilution, marrow infiltration, and marrow failure (aplastic anemia). Some morphologic clues to cause other than those pertaining to RBC morphology are discussed and illustrated. A working approach to the investigation of nonpoikilocytic normochromic normocytic anemia is suggested.
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PMID:Investigation of nonpoikilocytic normochromic normocytic anemia. 41 35

A total of 4939 apparently healthy Fijian and Indian subjects living in Fiji were tested for anaemia by determination of the microhaematocrit of a sample of capillary blood. The prevalence of anaemia during childhood varied with age but was similar for Fijians and Indians of either sex. The overall prevalences were: 0-4 years, 20.3%; 5-9 years, 3.7%; 10-14 years, 23.5%. The prevalence of anaemia among Indian women (33.3%) was substantially higher than that for Indian men (6.9%), Fijian women (8.1%) or Fijian men (6.8%). Iron deficiency was the most common cause of anaemia and was established by laboratory studies in 203 (68%) of 298 anaemic subjects who were followed up. Iron deficiency was an important aetiological factor in 91 (93%) of 98 subjects with moderate or severe anaemia. Folate deficiency was found, usually in combination with iron deficiency, in 44 or 141 anaemic indian adults were followed up. Folate deficiency was uncommon in Fijian adults and among children of either race. Two cases of nutritional vitamin B12 deficiency, one case of pernicious anaemia, 6 cases of heterozygous thalassaemia and one case of heterozygous haemoglobin E were found among the anaemic Indian subjects. No cases of vitamin B12 deficiency anaemia, thalassaemia or haemoglobinopathy were detected among the Fijians. In 5 Indians and 7 Fijians the anaemia was associated with an underlying chronic disorder. This study emphasizes that in Fiji, as in other developing countries, nutritional anaemia is prevalent among asymptomatic subjects. Iron deficiency is by far the most common cause.
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PMID:The prevalence and nature of anemia among apparently normal subjects in Fiji. 52 78

Patients with juvenile rheumatoid arthritis may have an anemia attributable to the chronic disease, to iron deficiency, or to a combination of the two. The contribution of iron deficiency is often difficult to determine by routine laboratory studies. We studied 51 patients with pauciarticular and polyarticular juvenile rheumatoid arthritis with red blood cell counts, indices, free erythrocyte protoporphyrin, and serum ferritin. Fifteen of the 18 who were anemic were restudied after a 3 to 6-month period of iron therapy. Thirteen of the 15 responded by these criteria: a rise in hemoglobin of 1.0 gm/dl or more and an increase in mean corpuscular volume of 3 fl or more; in 11 of these 13, hemoglobin values returned to the normal range for age. These findings indicate that iron deficiency can be a major component of the anemia that is commonly found in patients with active juvenile rheumatoid arthritis.
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PMID:Anemia in patients with juvenile rheumatoid arthritis. 66 Mar 58

This article on microcytic anemia is the first of several on laboratory investigation of anemia. Microcytic anemia, characterized by a mean corpuscular volume of less than 80 cu mu, is usually due to iron deficiency or chronic disease but may signify thalassemia minor. Exact identification of the cause is important, since inappropriate iron therapy may be useless or even dangerous.
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PMID:Investigation of microcytic anemia. 76 90

Haemoglobin concentration was determined in all patients (530) over 70 years of age in a general practice in Oslo during an eight month period. 72 had anaemia and were investigated further. Iron deficiency was found in 13 patients and was most often caused by gastrointestinal blood loss. Chronic diseases, particularly chronic infections and rheumatoid arthritis, were responsible for anaemia in 34 patients. Renal failure caused anaemia in 14 patients. In 10 patients we found no explanation for the anaemia. Nine patients with a previously undiscovered disease were found, six of whom could be offered some kind of treatment. We conclude that anaemia in elderly patients in general practice is often caused by chronic diseases. The main cause of iron deficiency is blood loss, and routine prescription of iron is not justified in this age group. The therapeutic benefit from routine measurement of haemoglobin concentration is small and the test should be used selectively.
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PMID:Anaemia in elderly patients. Incidence and causes of low haemoglobin concentration in a city general practice. 175 48

A total of 128 leprosy patients were investigated for the morphological type of anaemia, the underlying disturbances in iron metabolism and patterns of erythropoiesis and other cytomorphological changes in the bone marrow. The anaemia was a mild to moderate degree in paucibacillary (PB) leprosy, while in multibacillary (MB) leprosy it was of a severe degree. Iron deficiency was observed in only a few patients. Impaired iron utilization as observed in a anaemia of a chronic disorder was a common finding in MB leprosy (41.7%) and more so in new cases (50%). Megaloblastic erythropoiesis was also more frequent in MB leprosy (45.2%) as compared to PB leprosy (16%), accounting for the severe degree of anaemia in the former type. In 17.2% of the total patients (MB, 21.4%; PB, 9%) both megaloblastic erythropoiesis and features of impaired iron utilization were observed in bone marrow. Disturbances in iron metabolism and erythropoiesis were also observed but to a lesser degree in patients receiving specific antileprosy treatment. Irrespective of the type of disease and duration of treatment, increasing frequency of acid-fast bacillia (AFB) positivity and granulomas was observed in the bone marrow with an increasing severity of anaemia.
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PMID:Patterns of erythropoiesis and anaemia in leprosy. 187 Mar 78


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