Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hemoglobin Crete, beta129 (h7)ala leads to pro, is a new mutant hemoglobin (Hb) with high oxygen affinity that was discovered in a Greek family in various combinations with beta- and deltabeta-thalassemia. The propositus, who presented an unusual clinical picture of an "overcompensated" hemolytic state, with erythrocytosis, splenomegaly, abnormal red cell morphology, and marked erythroid hyperplasia, appeared doubly heterozygous for Hb Crete and deltabeta-thalassemia. His red cells contained 67% Hb Crete and 30% Hb F, and the combination of these two hemoglobins resulted in a blood P50O2 of 11.2 mm Hg. A brother with Hb Crete trait (38% Hb Crete, 56% Hb A, blood P50O2 23.0 mm Hg) did not have significant erythrocytosis. Purified Hb Crete was heat-unstable and exhibited a high oxygen affinity, and a normal Bohr effect. We postulate that the beta 129 proline substitution disrupts the H helix, perturbing nearby residues involved in alpha 1 beta 1 contact sites of the Hb tetramer.
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PMID:Hemoglobin Crete (beta 129 ala leads to pro): a new high-affinity variant interacting with beta o -and delta beta o -thalassemia. 3 84

Mass screening in the Geok-chai region of Azerbaijan covered 264 persons. 2 families with abnormal hemoglbin were detected. Electrophoresis in PAG and on cellulose acetate films as well as sickling test showed that in 3 out of 9 members of one of the families HbS was detected. 6 out of 8 members of the others family appeared to be HbD-carriers. In 4 members of this family abnormal hemoglobin was found out in combination with G-6-PDH deficiency. No clinical manifestations were found. A number of beta-thalassemia cases were detected in screened children as well as in adults. Hemoglobin oxygen equilibrium curves were studied in patients with heterozygous beta-thalassemia. In case of G-6-PDH deficiency when it is not possible to obtain active enzyme zones on the columns with PAG these zones can be detected when CoCl2 (2 mM) is added into the incubation medium.
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PMID:Hemoglobinopathies and glucose-6-phosphate dehydrogenase deficiency in one of the regions of Azerbaijan: mass screening and laboratory investigations. 14 87

Because their blood may "unload" oxygen more readily than normal, people with hemoglobin of low oxygen affinity might be expected to be anemic. We have studied a woman with hemoglobin Hope/beta+ thalassemia, whose hemoglobin level was 10.4 to 12.3 gm/dl (normal 14 +/- 2) despite a P50 of 41 mm Hg (normal 26). Her cardiac index was normal, yielding a calculated mixed venous PO2 of 51 mm Hg (normal 34 to 49). Oxygen transport in patients with low oxygen affinity can be maintained by a variety of homeostatic responses, only one of which is altered erythropoiesis.
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PMID:Oxygen transport in a woman with hemoglobin Hope/beta+ thalassemia. 42 43

Polarographic titration in a closed cell of blood samples and concentrated Hb solutions was used to study the regulation of the release of oxygen by the red cell. The effect of temperature, polyethylenglycol and metabolites normally found in the erythrocyte was determined by spectrophotometric and polarographic methods. Some pecularities of O2-transport and release in beta-thalassemia, functional hypoxia and Cooley-disease are described.
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PMID:[Functional characteristics of normal and pathologic erythrocytes]. 60 82

The applicability to red blood cells of two widely used methods for spectrophotometric assay of superoxide dismutase activity has been tested, in view of the demand for routine screening of the level of this enzyme in various circumstances of hematological interest. The nitro blue tetrazolium reduction method was found to be inapplicable, even after removal of hemoglobin by chloroform-ethanol extraction. On the other hand, the epinephrine oxidation method gave reliable values after chloroform-ethanol extraction. The enzyme content in normal adults was found to be 6.2 +/- 1.4 X 10(15) gr. per red blood cell. No significant change in the enzyme content was found in 19 patients with beta-thalassemia major and 5 patients with beta-thalassemia intermedia, indicating no influence on the level of this enzyme by the increased flux of oxygen radicals which is to be expected in thalassemic red blood cells.
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PMID:Superoxide dismutase in red blood cells: method of assay and enzyme content in normal subjects and in patients with beta-thalassemia (major and intermedia). 93 20

Further studies have been carried out on blood of the 15-year-old Negro male from Baltimore who was the first reported case of the homozygous state for hereditary persistence of fetal haemoglobin. His red cells contain only Hb F; Hbs A and A2 have never been detected. Over a 15-year period of follow up the red cells of this individual have shown persistent microcytosis with reduced MCH and MCV values. His whole-blood p50 value is decreased, probably because of lack of interaction between Hb F and 2,3-diphosphoglycerate. However, his haemoglobin level at the age of 15 years is lower than would be predicted from the degree of increased oxygen affinity. Globin-chain synthesis studies suggest that this is because he has a mild thalassaemia disorder with an alpha/gamma-chain production ratio of about 1.5, similar to that found in beta-thalassemia heterozygotes. Thus Negro HPFH appears to be a well-compensated form of delta beta thalassaemia.
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PMID:The Negro variety of hereditary persistence of fetal haemoglobin is a mild form of thalassaemia. 99 Jan 87

The knee of a boy with sickle-cell thalassemia became infected with Salmonella enteritidis, sensitive to ampicillin. Doses of ampicillin that achieved anti-bacterial titers of 32 in synovial fluid failed to eradicate the organism. The synovial fluid exhibited severe hypoxia, hypercapnia, and lactic acidosis. Methods were developed to estimate the oxygen saturation of blood in regional venous capillaries, the degree of periarticular sickling, changes in the viscosity of local blood, and the articular ratio of blood flow to oxygen utilization. The results suggest that local vascular insufficiency associated with sickling may affect host response to infection and efficacy of antibiotics. The Salmonella C1 readily transformed to an L form on hypertonic medium, thus acquiring resistance to ampicillin and other cell-wall inhibitors.
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PMID:Septic arthritis in sickle-cell thalassemia. Pathophysiology of impaired response to infection. 109 70

Oxygen dissociation studies were carried out on haemoglobin E (Hb E) at both high and low haemoglobin concentrations. Oxygen affinities of fresh red cells from three people homozygous for Hb E and from one with Hb E-beta thalassaemia (Hb-E trait/beta-thal trait) were low in three out of four patients studied, while the oxygen affinity of red cells from an individual with Hb-E was normal 2,3-DPG concentration in the fresh cells from the people with homozygous Hb E or Hb-E trait/beta-thal trait which showed low oxygen affinities were elevated sufficiently to account for the shifts observed. When the cells from two of these people with homozygous Hb E were depleted of 2,3-DPG. their oxygen affinities became the same as that of similarly treated normal cells. Pure 'stripped' Hb E in dilute solution behaved identically to Hb A in respect of P50, Bohr shift, haem-haem interaction, and interaction with inorganic phosphate or 2,3-DPG. Hb E, therefore, has the same oxypgen dissociation properties as Hb A both in dilute solution and in the red cell. The low oxygen affinities found in the fresh cells and in whole blood are caused by high 2,3-DPG concentrations within the cell.
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PMID:The oxygen affinity of haemoglobin E. 120 Dec 9

The role of red cell 2,3-diphosphoglycerate (2,3-DPG) in increasing the availability of haemoglobin oxygen in neonatal jaundice and hereditary haemolytic anaemias was investigated. Measurements of 2,3-DPG were carried out on 58 normal children and six normal adults, 18 full-term newborns with neonatal jaundice and 57 cases (51 children and six adults) with hereditary haemolytic anaemias. In normal children and adults, with a mean haemoglobin of 12.69 g/dl, mean 2,3-DPG was 14.90 mumol/g Hb. In jaundiced newborns with a mean haemoglobin of 16.04 g/dl mean 2,3-DPG levels were 14.51 mumol/g Hb, i.e. normal. 2,3-DPG levels were increased in patients with beta-thalassaemia major, alpha-thalassaemia, sickle-cell disease, favism, hereditary spherocytosis and in heterozygotes for beta-thalassaemia with increased haemoglobin F. In heterozygotes for beta-thalassaemia with increased haemoglobin A2 only and in sickle cell trait 2,3-DPG levels were normal.
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PMID:Red cell 2,3-diphosphoglycerate levels in children with hereditary haemolytic anaemias. 123 8

Hematologic and globin synthesis studies were performed in a black American family in which the genes for alpha-thalassemia and hemoglobins (Hb) S and C were segregating. The following distribution of these abnormalities was found: father, sickle cell trait + alpha-thalassemia; mother, HbC trait + alpha-thalassemia, propositus, HbSC + alpha-thalassemia; older sibling, alpha-thalassemia trait; and younger sibling, hemoglobin H disease. The child with HbSC-alpha-thalassemia demonstrated more severe anemia and a more hemolytic picture than is typical of HbSC disease. Her erythrocytes exhibited decreased osmotic fragility in comparison with HbSC erythrocytes, but had an indistinguishable oxygen equilibrium curve and 2, 3-diphosphoglycerate (2, 3-DPG) level. Erythrocyte sickling in the patient, however, was significantly reduced, with less than 35% sickle forms observed at nearly complete oxygen desaturation. The sibling with hemoglobin H disease exhibited 26% Bart's (gamma4) hemoglobin at birth, a level comparable with that seen in infants with HbH disease in Far Eastern populations. At age 5 months typical findings of mild hemoglobin H disease appeared, with HbH making up 6.5% of the total hemoglobin.
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PMID:Sickle cell syndromes. I. Hemoglobin SC-alpha-thalassemia. 127 38


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