Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Belgrade rats have an autosomal recessive anemia with hypochromia and microcytosis. Iron uptake into reticulocytes is approximately 20% of normal, but transferrin uptake is unimpaired. We have systematically compared the transferrin cycle in Belgrade versus normal reticulocytes to locate the defect more precisely. Belgrade transferrin was functionally normal as purified transferrin or whole plasma. Transferrin affinity of Belgrade receptors was indistinguishable from normal, but Belgrade reticulocytes had twice as many receptors. Belgrade transferrin endocytosis was 1.5 times faster than normal, whereas exocytosis is about twice as fast. Initially Belgrade reticulocytes internalize iron at an unimpaired rate, but they lag behind normal by 5 min. During reincubation, they release 25-33% of iron taken up during a 30-min preincubation, whereas normal cells do not lose a detectable fraction. Unexpectedly, transferrin cycle time was unchanged. Hence another kinetic step of the cycle is slower, compensating for increases in Belgrade endocytosis and exocytosis. After one cycle, Belgrade reticulocytes retain only half of the iron that entered, but over 90% of iron entering normal cells remains within. Iron unloading is ineffective inside the Belgrade vesicle; 85% of iron that entered on transferrin returned to the medium after exocytosis, whereas only 45% of iron entering normal reticulocytes exits. Ineffective utilization of iron in or near Belgrade endosomes accounts for the Belgrade defect.
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PMID:Transferrin and the transferrin cycle in Belgrade rat reticulocytes. 832 65

Using an in vitro technique the ability of the Fe/Transferrin complex in the serum of calories and proteins in chronically deprived adult males was investigated. The study included the behavior of the same function in the sera of other types of anemias. A significant reduction of the Fe donating capacity was found in the sera of patients suffering from nutritional anemia (NA), whereas this change was absent in the sera of other type of anemias. A deterioration of the iron donating function of the Fe/Transferrin complex caused by malnutrition, is postulated. The participation of this alteration in the production of NA is considered.
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PMID:[Ability of the Fe-transferring complex to transfer Fe to reticulocytes in nutritional anemia]. 837 85

To determine the etiology of hypoferremia in recently sedentary hunter-gatherers, a community located in the Kalahari Desert of Botswana was studied. Iron profiles of 106 Basarwa (Bushmen, San) volunteers were examined. Hematocrits were measured in the field. The remaining blood was processed for transportation to a research medical laboratory for further studies. Subnormal serum iron values were present, depending on the subpopulation, in 50-52% of the volunteers. Transferrin saturation was subnormal in 35-49% of those tested. The absence of subnormal serum ferritin levels indicates that dietary iron deficiency is not the cause of the hypoferremia. Instead, serum ferritin was greater than 50 micrograms/l (a level indicative of anemia of chronic disease/inflammation) in 92% of the hypoferremic adult Basarwa. We suggest that by depriving microbes of needed iron, the frequency of the anemia of infections and chronic disease in this population might be a response to, and defense against, a chronically high pathogen load in a community that has not yet incorporated sanitation practices appropriate for sedentary aggregations.
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PMID:Etiology of hypoferremia in a recently sedentary Kalahari village. 848 Aug 65

Recombinant human erythropoietin (rHuEpo) seems to be more efficient when given subcutaneously (SC) instead of intravenously (IV) for therapy of anaemia in haemodialysis patients. This was a cross-over study designed to assess the efficiency of rHuEpo when given SC rather than IV in a 1 year follow-up. Sixteen patients received IV rHuEpo for 6 months, then SC rHuEpo for 6 months. They were four males and 12 females with a mean age of 56 years (range 15-82). Haemoglobin concentration ([Hb]) was kept at 10 g/dl and transferrin saturation (TS) at more than 25%. Mean [Hb] was 9.7 +/- 1.0 g/dl with IV rHuEpo and 9.9 +/- 0.9 g/dl with SC rHuEpo (NS). Transferrin saturation was 27% before rHuEpo, 31% with IV rHuEpo and 34% with SC rHuEpo (NS vs IV rHuEpo). Serum ferritin was 691 +/- 113 ng/ml before rHuEpo, 652 +/- 94 ng/ml with IV rHuEpo and 997 +/- 132 ng/ml with SC rHuEpo (P < 0.05 vs IV rHuEpo). Intact parathyroid hormone was 354 +/- 83 pg/ml before rHuEpo, 201 +/- 63 pg/ml with IV rHuEpo and 122 +/- 33 pg/ml with SC rHuEpo (NS vs IV rHuEpo). Doses of IV rHuEpo were 156 +/- 24 U/kg/week and SC rHuEpo 74 +/- 13 U/kg/week (i.e. a saving of 53%; P < 0.001). We conclude that subcutaneous administration of rHuEpo is twice as efficient as IV rHuEpo in patients with good functional iron reserve.
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PMID:Subcutaneous versus intravenous administration of erythropoietin improves its efficiency for the treatment of anaemia in haemodialysis patients. 852 93

We studied serum transferrin and ferritin concentrations in relation to individual body growth, stage of puberty, blood hemoglobin, and red blood cell iron (RBCI) in 60 prepubertal or early pubertal boys at 3-mo intervals for 18 mo. One-third of the boys had increased serum transferrin concentrations and almost all had decreased ferritin concentrations during the followup. No change in mean transferrin was observed but the individual 18-mo increments in transferrin correlated positively with the increments in hemoglobin (r = 0.55, P < 0.001) and in estimated RBCI (r = 0.31, P = 0.02). Serum transferrin remained stable at different genital stages, but ferritin was lower in the pubertal than in the prepubertal boys. Transferrin concentrations at 18 mo correlated positively with the preceding weight velocities. The rise in transferrin did not lead to an increase in iron-deficiency anemia. In contrast, transferrin rose in boys whose hemoglobin increased. In pubertal boys with relatively ample iron status, serum transferrin may be an indicator of increased availability of iron for erythropoiesis. The declining ferritin concentration indicates that part of the extra iron is mobilized through redistribution from stores to red blood cell mass and is generally associated with greatly increasing absorption. Thus, the pubertal changes in transferrin and ferritin are not necessarily indications of iron deficiency.
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PMID:Serum transferrin and ferritin in pubertal boys: relations to body growth, pubertal stage, erythropoiesis, and iron deficiency. 856 Oct 58

Anemia of chronic renal failure (CRF) prior to initiation of dialysis is an important cause of morbidity and requires early therapeutic intervention. The current study was designed to investigate the efficacy and tolerability of a therapeutic algorithm for anemia of CRF in pre-dialysis patients which is based on low dose once-a-week subcutaneous (s.c.) administration of recombinant human erythropoietin (r-HuEPO). Thirty-one patients participated in a prospective open-label multicenter study. At baseline, hemoglobin was 8.8+/-0.1 g/dl, transferrin saturation 27+/-2%, ferritin 207+/-28 ng/ml and serum creatinine 4.7+/-0.2 mg/dl. Treatment with r-HuEPO was started at a fixed s.c. dose of 4,000 units once weekly, irrespective of body weight, and titrated upwards or downwards according to a predetermined algorithm. Hemoglobin rose to levels >10 g/dl within 8 weeks and remained stable throughout the remaining period of the study. By week 24, most patients required <or =4,000 units/week as maintenance dose. Transferrin saturation and ferritin concentration tended to fall during the course of r-HuEPO treatment, despite iron supplementation. There was no change in white blood cell or platelet count. Eight patients required an increase in antihypertensive therapy, but blood pressure remained well-controlled. Twelve patients failed to complete the full length of the study, 7 of them because dialysis had to be initiated. The rate of decline in kidney function, however, was not altered by r-HuEPO. We conclude that the proposed therapeutic algorithm is practical, efficacious, safe, and cost-effective.
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PMID:Proposed therapeutic algorithm for the treatment of anemia of chronic renal failure in pre-dialysis patients with low dose once weekly subcutaneous r-HuEPO. Multicenter Study Group, Israel. 920 16

About 220 children (110 boys and 110 girls) aged 18 months to 10 years, 65.9% have been selected from anamnesis, clinical, and biological criteria to produce reference values on specific proteins dependent inflammatory, anemia and hemolysis (C-reactive protein = CRP; Transferrin = TRF and Haptoglobin: HPT). Specimens have been analysed by Nephelometric immuno-chemical method. For the two groups, A1 [18 months-5 years] and A2 [5-10 years], the reference values of the whole study population are reported: CRP (A1 3.35 +/- 3 mg/l: A2 2.40 +/- 2.30 g/l, with a significant difference at Student Fisher "t" test p < 0.03); TRF (A1 4.05 +/- 1.5 g/l; A2 4.50 +/- 1.4 g/l; NS, p > 0.05) HPT (A1 2.55 +/- 2.0 g/l: A2 1.20 +/- 1.10 g/l; S(r) p < 10(-5)). Furthermore, for TRF, HPT we must consider the sex in the results meaning because of significant difference into boys and girls.
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PMID:[Selection criteria for the establishment of reference values in tropical zones. Application to specific proteins: C-reactive protein, haptoglobin, transferrin in gabonese children]. 926 48

Early detection of iron sufficiency at the level of the erythropoietic cell is necessary to optimize management of uremic anemia with recombinant human erythropoietin (rHuEPO). "Absolute" and "functional" iron deficiency are the most important factors causing resistance to administered rHuEPO. Transferrin saturation and serum ferritin measurements have been noted to be insensitive and inaccurate measures to detect functional iron deficiency. Recently, the reticulocyte hemoglobin content (CHr) has been shown to be a sensitive and specific indicator of functional iron deficiency in nondialysis patients treated with rHuEPO. The purpose of this study is to compare CHr with currently used indices of iron sufficiency in rHuEPO-treated hemodialysis (HD) patients. In study 1, 364 stable HD patients were studied at two outpatient dialysis centers. CHr was normally distributed, with a mean value of 28.3 pg, and was consistent over two consecutive monthly samples in each center. CHr was weakly but consistently correlated with transferrin saturation and serum ferritin. CHr and reticulocyte number were inversely correlated with red blood cell (RBC) number, suggesting that the erythropoietic stimulus of routinely administered rHuEPO may have resulted in functional iron deficiency. Month-to-month changes in CHr correlated weakly with changes in serum iron and percent transferrin saturation, but not at all with changes in serum ferritin. When we analyzed those patients with baseline CHr less than 26 pg, a level strongly suggestive of functional iron deficiency, these correlations strengthened, and in addition, month-to-month changes in CHr correlated strongly and directly with concomitant changes in RBC count, hemoglobin, and hematocrit, suggesting that rising CHr was indicative of an erythropoietic response. In study 2, 79 patients received a single-dose infusion of 500 mg iron dextran. After intravenous iron, CHr rose within 48 hours, peaked at 96 hours, and then fell toward baseline. Patients who were iron deficient by standard measures (serum ferritin < 100 ng/mL or transferrin saturation less than 20%) had a greater and a sustained CHr response to intravenous iron dextran. A CHr less than 28 pg at baseline predicted functional iron deficiency, defined as a corrected reticulocyte increase of greater than 1% to iron dextran, more accurately than transferrin saturation, ferritin, or their combination. Eighty-two percent of individuals who were iron deficient at baseline responded to intravenous iron with an increase in CHr of greater than 2 pg. Sixty percent of patients who were iron sufficient by usual iron indices also responded to intravenous iron with a CHr rise of greater than 2 pg, suggesting that they were, in fact, functionally iron deficient despite "normal" conventional iron parameters. We conclude that CHr may be a more sensitive marker of functional iron deficiency in rHuEPO-treated hemodialysis patients than percent transferrin saturation and ferritin, particularly in those with "normal" conventional iron parameters.
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PMID:Reticulocyte hemoglobin content predicts functional iron deficiency in hemodialysis patients receiving rHuEPO. 939 41

We examined the value of transferrin concentrations in estimating nutritional status as determined by the subjective global assessment (SGA) score. Fifty-nine hemodialysis patients (37 men and 22 women, aged 59+/-16 years, dialyzed for 3.6+/-3.9 years) were selected by predetermined criteria. All received erythropoietin (EPO) and oral iron therapy. SGA evaluation was conducted twice by both a dietitian and a physician. Serum iron, total iron-binding capacity (TIBC; which is linearly correlated with transferrin), transferrin saturation ratio, ferritin, albumin, total protein, and cholesterol were measured. Twenty-seven (46%) patients were well nourished (group A), 20 (34%) were moderately nourished (group B), and 12 (20%) were poorly nourished (group C) according to the SGA. TIBC values were 276+/-47 mg/dL, 217+/-54 mg/dL, and 176+/-41 mg/dL, respectively (P < 0.00001), and thus directly correlated with the state of nutrition. The relationship between TIBC and nutritional status was independent of age and number of years on hemodialysis. Serum ferritin values were 104+/-93 ng/mL, 161+/-154 ng/mL, and 363+/-305 ng/mL, respectively (P < 0.0003), and thus inversely correlated with the state of nutrition. Transferrin saturation ratios were slightly higher in the severely malnourished patients. The number of years on dialysis were a determinant of nutritional status. These values were 2.4+/-2.4 years for group A, 3.9+/-4.0 years for group B, and 5.7+/-3.9 years for group C (P < 0.05). The average age of the poorly nourished patients was 10 years older than the well-nourished patients. Serum iron values were lower but transferrin saturation ratios were higher in the severely malnourished patients. The required EPO doses were higher in the poorly nourished patients. We suggest that transferrin values are superior to other laboratory tests in assessing nutrition and will supplement SGA criteria. Serum ferritin may be useful as a predictor of illness. Older patients who have been on dialysis longer warrant special concern. Malnutrition may be an indicator of EPO resistance in dialysis patients. Finally, since a decreased TIBC level in poorly nourished patients may erroneously increase the transferrin saturation ratio, our findings may have implications in making the diagnosis and treatment of anemia and iron deficiency in malnourished dialysis patients.
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PMID:Total iron-binding capacity-estimated transferrin correlates with the nutritional subjective global assessment in hemodialysis patients. 946 97

A 72-year-old patient presented himself with typical symptoms of coronary heart disease and was scheduled for invasive diagnostic procedures. Cardiac risk factors were smoking and arterial hypertension. The physical examination was inconspicious. In the laborchemistry a hemoglobin of 79 g/l with a mean corpuscular volume of 63 fl and a mean corpuscular hemoglobin of 20 pg was conspicuous. The serum iron was with 42 micrograms/dl in the lower norm. Transferrin, bili-rubin and lactate dehydrogenase were normal. Then in the gastrointestinal investigations he was diagnosed with a leiomyoma of the intestine that led to chronic anaemia and additionally to chest pain characteristic for angina pectoris. After the removal of the tumor and normalization of hemoglobin this patient was free from symptoms of the disease. The coronary angiography revealed a complex stenosis of the right coronary artery with collaterales and not significant stenosis both of the left coronary arteries. In patients with angina pectoris anaemia as the possible and only cause of angina ought to be verified. It is therefore necessary after normalization of hemoglobin and clarification of the cause for the anaemia to apply a test for coronary ischemia.
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PMID:[Angina pectoris in leiomyoma]. 975 77


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