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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A child with homozygous sickle cell disease and transposition of the great vessels had erythrocytosis associated with markedly increased plasma erythropoietin activity. Her clinical course was complicated by neurologic manifestations but not by recurrent sickle cell vasooculsive episodes. The fetal hemoglobin level which had been greater than 25% during the first two years of life gradually decreased to less than 10%. She died at 3 years of age of congestive heart failure and severe anemia. The only sickle cell painful crisis occurred during her terminal illness. It is likely that the high levels of fetal hemorglobin decreased sickling and thus allowed erythrocytosis to develop. Fetal hemoglobin may also have prevented frequent vaso-occlusive events despite the high hematocrit level.
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PMID:Sickle cell anemia and transposition of the great vessels. 62 79

The disturbed balance of globin chain synthesis is a major factor in the pathophysiology of the thalassaemic disorders; this concept is strongly supported by the study of a patient displaying an extreme but symmetrical deficit of both major types of chains alpha and beta. The patient had a mild clinical picture but presented a striking hypochromia (MCH 10 pg) with compensatory erythrocytosis (RBC 10(12)/l.). Study of the propositus and his family by haematological, biochemical and biosynthetic techniques indicates that the patient carries two alpha- and two beta-thalassaemia genes resulting in balanced globin chain synthesis; in addition, several members of the family carry two or three abnormal genes. During observation a change in the haematological pattern occurred with a shift towards more intensive beta-chain and away from gamma-chaim synthesis; this appeared with be associated with improvement of his anaemia through more effective erythropoiesis.
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PMID:A unique thalassaemic syndrome: homozygous alpha-thalassaemia + homozygous beta-thalassaemia. 69 15

30 patients with tetralogy of Fallot were examined before and after correction. 10 of whom had previous procedures including 13 Blalock-Taussig shunts, 1 Cooley anastomosis and 6 pulmonary valvulotomies (Brock) with a dilator. Hemoglobin and blood gases were measured in 22 patients pre- and postoperatively on the 7th respectively 14th day and finally after 12 months. In 8 children the concentration of 2,3-DPG was accessed (pre-, postoperatively, immediately in ICU, on the 1st, 7th, 14th day and after 21 months). Hypoxia of various degrees was found at any time of the investigation, verified by a low venous oxygen saturation, high 2,3-DPG concentration and an erythrocytosis. The 2,3-DPG concentration was always elevated (preoperatively 18.2 +/- 1.8 muMol/g Hb; postoperatively 1st till 14th day 19.0 +/- 2.2; after 21 months 16.3 +/- 1.2 muMol/g Hb). Preoperatively hypoxia was correlated to the degree of the heart disease expressed by the hight of the Hb-concentration. In contrary after the correction signs of hypoxia (decreased venous oxygen saturation, increased 2,3 DPG-concentration) appeared with a low Hb as found in patients with anemia. The long term check-ups are indicative for slight cardiac residual disorders as there are hypoxic myocardial damage, residual gradients over the right ventricular outlet, reopened VSD's, and ventriculotomy scar tissue. Though the elevated 2,3-DPG-concentration and the consecutive rightward shift of the oxygen saturation curve obviously compensate these cardiac handi-caps as the excellent physical condition of the children shows.
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PMID:[Correction of tetralogy of Fallot and its influence to oxygen transport and lung changes. Part I. Oxygen transport (author's transl)]. 84 77

Using a methylcellulose clonal cell culture technique, we examined serial changes in erythropoietic precursors in the femur, spleen, and blood of mice prepared with bleeding, erythropoietin injections, or hypertransfusion with packed red blood cells. Significant changes were observed for all hemopoietic organs in the number of erythropoietic burst-forming units (BFU-E) and erythrocytic colony-forming units (CFU-E). In mice prepared with bleeding or erythropoietin injections, the serial changes of BFU-E and CFU-E were similar to but less striking than those seen in mice with phenylhydrazine-induced anemia. The transient decline in the femoral BFU-E coincided with the temporary increase in the splenic and blood BFU-E. A more pronounced increase in CFU-E was noted in the femur and spleen of these mice. In hypertransfused mice, the direction of the changers in the erythropoietic precursors was opposite. While femoral BFU-E increased mildly, a significant drop was noted in the splenic and blood BFU-E. Both femoral and splenic CFU-E declined and remained low while erythrocytosis presisted. Next, we examined the proliferative state of the erythropoietic precursors in the marrow and spleen using short-term incubation with high specific tritiated thymidine. In the marrow and spleen of normal mice, the BFU-E and CFU-E in the DNA synthetic phase was about 36 and 74%, respectively. Neither induction of anemia with phenylhydrazine hydrochloride nor polycythemia with hypertransfusion caused changes in the proliferative state of the precursors. These results indicate that the serial changes in the number of BFU-E represent migration of BFU-E from marrow to spleen rather than BFU-E proliferation. Marrow CFU-E increased in anemic mice and decreased in polycythemic mice without changes in their proliferative state. It is possible that the target of erythropoietic stimulation in mice may be cells at maturational stages intermediate between BFU-E and CFU-E.
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PMID:Erythropoietic precursors in mice under erythropoietic stimulation and suppression. 84 18

The clinical hematologic change in 2 groups of progeny from mice carrying radiation-induced strain SEC alpha-chain deficiencies was found to be similar to the hematologic alterations in persons with alpha-thalassemia. The heterozygous deletion or inactivation of the alpha-chain gene in mice caused an anemia similar to alpha-thalassemina minor in persons. The alpha-chain deficiency in mice created an erythrocytosis, reticulocytosis, and microcytic, hypochromic anemia comparable with the changes in human alpha-thalassemia minor resulting from deletion of the alpha-chain gene. These mouse mutants are the only known animal models of human thalassemia. A comparison of hematologic values obtained from progeny possessing an alpha-chain gene deficiency and from progeny possessing a beta-chain duplication suggested that the deficiency of alpha-chain synthesis, rather than a simple imbalance between the amounts of alpha- and beta-chains produced, was primarily responsible for the altered hematologic characteristics in these alpha-thalassemic mice.
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PMID:Radiation-induced alpha-thalassemia in mice. 87 56

In a study of 30 patients with hypernephromas, 23 patients manifested systemic effects of the tumor, and in 5 of these, the systemic effects were the presenting feature that led to the diagnosis. In contrast to this, only 17 patients had urologic complaints, and no single patient in this study had the classic triad of hematurial, loin pain, and mass. Weight loss (52 per cent), pyrexia, and elevated sedimentation rate (36 per cent) were seen most frequently. Anemia was seen in 25 per cent of patients. Other features seen in this group wer abnormalities in liver function, elevated alkaline phosphatase, hypertension, erythrocytosis, and hypercalcemia. In the majority of instances, removal of tumor was associated with remission of these effects. The effects were classified as those of a general toxic nature, those due to normal or abnormal production of hormones, and those due to production of abnormal substances by tumor cells. The evaluation of these effects was useful in making an early diagnosis and in follow-up care.
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PMID:Systemic effects of hypernephroma. 89 63

Qualitative and quantitative studies of erythropoiesis in 23 patients with hypothyroidism and 21 patients with hyperthryoidism included routine hematologic evaluation, bone marrow morphology, status of serum iron, B12 and folate red blood cell mass and plasma volume by radioisotope methods, erythrokinetics and radiobioassay of plasma erythropoietin. A majority of patients with the hypothyroid state had significant reduction in red blood cell mas per kg of body weight. The presence of anemia in many of these patients was not evident from hemoglobin and hematocrit values due to concomitant reduction of plasma volume. The erythrokinetic data in hypothyroid patients provided evidence of significant decline of the erythropoietic activity of the bone marrow. Erythroid cells in the marrow were depleted and also showed reduced proliferative activity as indicated by lower 3H-thymidine labeling index. Plasma erythropoietin levels were reduced, often being immeasurable by the polycythemic mouse bioassay technique. These changes in erythropoiesis in the hypothyroid state appear to be a part of physiological adjustment to the reduced oxygen requirement of the tissues due to diminished basal metabolic rate. Similar investigations revealed mild erythrocytosis in a significant proportion of patients with hyperthyroidism. Failure of erythrocytosis to occur in other patients of this group was associated with impaired erythropoiesis due to a deficiency of hemopoietic nutrients such as iron, vitamin B12 and folate. The mean plasma erythropoietin level of these patients was significantly elevated; in 4 patients the levels were in the upper normal range whereas in the rest, the values were above the normal range. The bone marrow showed erythyroid hyperplasia in all patients with hyperthyroidism. The mean 3H-thymidine labeling index of the erythroblasts was also significantly higher than normal in hyperthyroidism; in 8 patients the index was within the normal range whereas in the remaining 13 it was above the normal range. Erythrokinetic studies also provided evidences of increased erythropoietic activity in the bone marrow. It is postulated that thyroid hormones stimulate erythropoiesis, sometimes leading to erythrocytosis provided there is no deficiency of hemopoietic nutrients. Stimulation of erythropoiesis by thryoid hormones appears to be mediated through erythropoietin.
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PMID:Erythropoiesis and erythropoietin in hypo- and hyperthyroidism. 111 76

Hemoglobinopathies in the strict sense most often involve single amino acid substitutions. The clinical consequences, if any, are anemia, erythrocytosis and met-hemoglobinemia. In the thalassemias, which are characterized by microcytosis, unbalanced synthesis of normal globin chains exists and disease severity is primarily determined by the amount of relative overproduction of the unaffected chain: thus, the unstable chain tetramers precipitate and lead to ineffective erythropoiesis and hemolysis. The sideroblastic anemias are a heterogeneous group of pathological conditions, both clinically and pathogenetically. Heme synthesis appears to be regularly disturbed, but this is probably not the sole defect. Other alterations of globin and heme synthesis are listed and briefly discussed.
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PMID:[Disorders of hemoglobin synthesis (exclusive of iron deficiency)]. 118 39

Erythrocytosis, a known response to chronic hypoxemia, is considered infrequent in interstitial lung diseases. We studied the prevalence of high hematocrit (Hct) values and the relationship between Hct and SaO2 in 79 patients with chronic pigeon breeder's lung (PBL) and 34 with idiopathic pulmonary fibrosis (IPF), all of whom lived in the Mexico City metropolitan area (2,240 m above sea level). Lung biopsy was performed in 31 patients with IPF and 71 with PBL. We analyzed only one simultaneous measurement of Hct and SaO2 per patient (usually the initial measurement) before treatment. No additional cause for anemia or erythrocytosis was detected. Forty-eight percent of the patients with PBL (38/79) and 62 percent of those with IPF (21/34) had high Hct values (greater than 2 SD above mean values for Mexico City); in 14 (12.3 percent) of the 113 patients (nine with PBL and five with IPF), the Hct was above 60 percent. The Hct and SaO2 values displayed a poor correlation for the whole group: Hct = 65.7-0.16(SaO2), r = 0.24, p = 0.012. The correlation between Hct and SaO2 was nonsignificant if patients were separated by diagnosis. For an SaO2 of less than 80 percent, the slope of SaO2 vs Hct was zero. Half of our patients with PBL and IPF had Hct values that were high for the altitude. In most cases, Hct responses fell within the confidence limits reported as normal at high altitudes. We found a poor relationship between Hct and awake SaO2.
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PMID:Prevalence of high hematocrits in patients with interstitial lung disease in Mexico City. 160 Jul 93

Erythropoietin is a glycoprotein hormone that plays a vital role in erythropoiesis. It is mainly produced in the fetal liver till the third trimester of pregnancy. At that point, the kidney interstitium takes over this function and becomes the main source of erythropoietin. Hypoxia stimulates erythropoietin production by a mechanism that may require a heme protein as a second messenger. Erythropoietin stimulates the maturation of erythroid precursors (colony-forming unit-erythroid and burst-forming unit-erythroid) via at least two types of cell surface receptors. The higher-affinity receptors appear to be more important in modulating the effects of erythropoietin in vivo. Changes in intracellular calcium may ultimately mediate the action of erythropoietin on erythroid precursors. A specific and sensitive radioimmunoassay is now available for accurately measuring erythropoietin levels. All forms of erythrocytosis except polycythemia vera are associated with elevated erythropoietin levels. Levels are also high in cord blood obtained following fetal asphyxia. Reduced levels are seen in patients with anemia due to renal diseases. The response of erythropoietin to the degree of anemia appears to be attenuated in patients with cancer, chronic diseases, and human immunodeficiency virus (HIV) infection. Erythropoietin has been successfully used for treating patients with anemia due to renal failure. Its use has also been approved for the treatment of anemia patients receiving zidovudine for HIV infection. Encouraging results have been observed when erythropoietin was used to treat anemia due to rheumatoid arthritis, hematological malignancies, and prematurity. It has also been used to increase the yield of autologous blood collected prior to an elective surgical procedure. However, it has not proved to be useful in sickle cell anemia and myelodysplastic syndromes.
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PMID:Erythropoietin. Biology and clinical applications. 178 66


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