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)

Globin chain synthesis has been investigated for the first time in 2 patients homozygous for haemoglobin Lepore, although the 2 brothers have the same haemoglobin genotype the severity of the diseases is very different. The purpose of this study was to try and find out the reason for the different severity in the clinical manifestations. In the 2 patients a different excess of alpha-chain synthesis was observed, the higher excess being present in the subject carrying the more severe anaemia. This result strongly suggests that in homozygous haemoglobin Lepore disease, as in beta-thalassaemia, the degree of globin chain imbalance is responsible for the clinical manifestations.
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PMID:Synthesis of alpha, delta-beta and gamma chains by reticulocytes from two brothers homozygous for haemoglobin Lepore. 10 2

The sickle-cell gene contributes substantially to the presentation of anaemia in certain areas of the Arabian Peninsula. However, the clinical presentation of the homozygous state of Hb S is less severe than that observed in other ethnic groups, such as American negroes. In the present paper, biosynthesis studies performed on reticulocytes from heterozygotes and homozygotes for the Hb S give further indications of the mild nature of sickle-cell disease in Arabia. Comparison of two affected families, from Saudi Arabia and Jordan, showed that clinical manifestation of the disease is mirrored by the biochemical and haematological findings in affected individuals. The results are discussed in terms of the effect of co-existing thalassaemia and/or iron deficiency with Hb S. It is suggested that both genetic and acquired conditions play a role in the clinical features of the disease. The mechanisms responsible for regulation of alpha-chain synthesis by iron (haem) deficiency are discussed.
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PMID:On the nature of sickle-cell disease in the Arabian Peninsula. 53 90

Three patients with a relatively mild form of beta O-thalassemia who did not require regular blood transfusions are described. Globin synthesis was studied by gel filtration and urea-carboxymethylcellulose chromatography of stroma-free hemolysates prepared from peripheral blood and bone marrow cells labeled in vitro with 14C-leucine. gamma/alpha Synthetic ratios in peripheral blood were in the same range as in patients with the severe clinical form of beta O-thalassemia, while gamma/alpha synthetic ratios in bone marrow cells were higher than in that group of patients. The size of the free alpha-chain pool measured in one case was smaller than in other patients with "classical" Cooley anemia. It is concluded that the severity of the clinical course in beta O-thalassemia does not correlate with the imbalance in alpha verus gamma chain synthesis in peripheral blood and is determined by the synthetic ratio in bone marrow cells, where the bulk of hemoglobin synthesis takes place.
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PMID:Beta O-thalassemia intermedia. 66 61

Three siblings of a Kurdish Jewish family with clinical and hematologic findings compatible with congenital dyserythropoietic anemia (CDA) are described. All patients presented with mild anemia, marked hyperbilirubinemia and splenomegaly. The bone marrow morphology and ultrastructure of the normoblasts was typical of CDA type II and there was strong agglutination of the patients' red blood cells by anti-i serum. These patients displayed two features that were not characteristic of CDA type II, namely, the acidified serum lysis test was negative on more than 10 occasions, and high levels of Hb A2 were observed in two siblings. In one of the siblings, abnormal globin-chain synthesis was found and alpha-chain production exceeded beta-chain production, as in beta-thalassemia minor. In the light of the above findings, our patients are perhaps best classified as having aberrant CDA with features of thalassemia.
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PMID:Aberrant congenital dyserythropoietic anemia with negative acidified serum tests and features of thalassemia in a Kurdish family. 75 May 40

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

Erythrocyte survival, fecal stercobilinogen, and the alpha/beta-chain synthesis ratio in recticulocytes and bone marrow (six cases only) were determined and related to the hemoglobin levels in ten heterozygous carriers of beta-thalassemia with different degrees of anemia. Erythrocyte survival values were low, though not related to the degree of anemia, whereas stercobilinogen values and changes in the peripheral blood alpha/beta-chain ratios were so correlated. In the case of bone marrow, on the other hand, the ratio between alpha-chain and beta-chain synthesis was virtually 1, irrespective of the degree of anemia. It is suggested that the severity of anemia in heterozygous carriers is independent of peripheral hemolysis and entirely attributable to destruction of erythroblasts within the marrow.
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PMID:The relationship between anemia, fecal stercobilinogen, erythrocyte survival, and globin synthesis in heterozygotes for beta-thalassemia. 117 4

Haemoglobin M is a rare cause of congenital cyanosis and is usually misdiagnosed as being due to congenital heart disease. This was also the case in a family on whom this report is based. In five members of three generations the characteristic grey-blue cyanosis was due to a haemoglobin M anomaly. In all of them cardiopulmonary disease, anaemia and haemolysis had been excluded. The amino-acid substitution was in the alpha-chain of the globin molecule. Consequently the carriers of the trait have an abnormal haemoglobin content of 20-25%. Despite marked cyanosis they feel well.
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PMID:[Haemoglobin M-Homburg (author's transl)]. 125 2

alpha-Thalassaemia is a disturbance of the alpha-chain synthesis of the haemoglobin, which occurs mostly in the Far East. On account of the total absence of alpha-chains, the homozygous form is considered to be fatal. However, beta and lambda chains exist abundantly. Abortion, intrauterine or perinatal death are the results of the extreme anaemia (Hb-Bart's syndrome), despite modern intensive medical care. The prenatal diagnosis is possible by: 1. DNA analysis of material obtained by chorion villi sampling or culture of fibroblasts, when a risk of re-occurrence is known to the physician. 2. Hb-electrophoresis from foetal blood in cases of hydrops of uncertain origin. When the diagnosis of this fatal disease is established, there is no foetal indication for delivery by Caesarian section.
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PMID:[Alpha-thalassemia as a rare differential diagnosis of hydrops fetalis et placentae]. 228 18

Synthetic alphaT1 and betaT1, the N-terminal tryptic peptides of alpha-chain and beta-chain of hemoglobin, and MetalphaT1 and MetbetaT1, peptides in which N-terminal methionyl residues are peptide-bonded to alphaT1 and betaT1, were prepared by the solid-state method of Merrifield. These synthetic peptides were used to establish conditions for chromatographic purification and analysis. When tryptic digests of nascent globin chains from rabbit and sickle-cell anemia reticulocytes incubated with (35)S- and (3)H-labeled amino acids were analyzed, radioactivity not present in tryptic digests of labeled hemoglobin appeared at the elution positions of MetalphaT1 and MetbetaT1. The fraction of nascent chains with N-terminal methionine was higher in sickle-cell anemia reticulocytes than in rabbit reticulocytes. If rate of peptide-chain elongation in polysomes is uniform, nascent human chains must attain a greater length before removal of the initial methionyl residue. Length of nascent chain at time of removal was calculated from two independent sets of data, one obtained from [(35)S]methionine incorporation into MetalphaT1, MetbetaT1, alphaT5, and betaT5, and the other obtained from [(3)H]lysine and [(3)H]valine incorporation into MetbetaT1 and betaT1.
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PMID:Delayed removal of N-terminal methionine from nascent globin chains in sickle-cell anemia reticulocytes. 451 5

In five patients with sickle beta-thalassemia there was balanced alpha- and beta-globin synthesis in the bone marrow and decreased total beta-chain synthesis relative to that of alpha-chain in the peripheral blood. These findings are similar to those in patients with simple beta-thalassemia trait. Despite a range of hemoglobin concentrations from 6.8 to 12.5 g/100 ml in the patients with sickle thalassemia, there was no evidence of a significant excess of alpha-chains in the red cells of the bone marrow which could contribute to the hemolysis and anemia. In patients heterozygous for beta-thalassemia the capacity to synthesize beta-chain decreases more rapidly than that for alpha-chain. In nonthalassemic subjects the rates of beta- and alpha-chain synthesis decrease equally as the red cell matures. The beta(S)- and beta(A)-chains serve as convenient markers for globin synthesis due to the nonthalassemic and thalassemic alleles in patients with sickle beta-thalassemia. The unbalanced globin synthesis in the peripheral blood of these patients is explained by the decrease in relative synthesis of beta(S)-chain, in comparison with that of alpha-chain. This instability is not present in sickle cell trait. The beta(A)-chain synthesis was only unstable in the two patients who had the most marked anemia. The major mechanism for achieving balanced globin production in the bone marrow in the presence of one thalassemic gene appears to be increased synthesis of beta-chain due to the nonthalassemic allele. In addition, there may be a decrease of total alpha-chain synthesis in some patients.
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PMID:Synthesis of globin chains in sickle -thalassemia. 468 90


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