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)

Superoxide ions (O2-) oxidized oxyhaemoglobin to methaemoglobin and reduced methaemoglobin to oxyhaemoglobin. The reactions of superoxide and H2O2 with oxyhaemoglobin or methaemoglobin and their inhibition by superoxide dismutase or catalase were used to detect the formation of superoxide or H2O2 on autoxidation of oxyhaemoglobin. The rate of autoxidation was decreased at about 35% in the presence of both enzymes. The copper-catalysed autoxidation of Hb (haemoglobin) was also shown to involve superoxide production. Superoxide was released on autoxidation of three unstable haemoglobins and isolated alpha and beta chains, at rates faster than with Hb A. Reactions of superoxide with Hb Christchurch and Hb Belfast were identical with those with Hb A, and occurred at the same rate. Hb Koln contrasted with the other haemoglobins in that the thiol groups of residue beta-93 as well as the haem groups reacted with superoxide. Haemichrome formation from methaemoglobin occurred very rapidly with Hb Christchurch and Hb Belfast, as well as the isolated chains, compared with Hb A. The process did not involve superoxide production or utilization. The relative importance of autoxidation and superoxide production compared with haemichrome formation in the haemolytic process associated with these abnormal haemoglobins and thalassaemia is considered.
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PMID:Reactions involving superoxide and normal and unstable haemoglobins. 18 28

We have determined serum Zn, Fe, Cu and Mg in 42 patients aging from 3 months to 22 years with homozygous beta-thalassemia and thalassemia intermedia and in 36 control subjects of the same ages. Serum zinc was significantly decreased. Serum copper and iron were increased, but magnesium was found to be at normal levels.
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PMID:Changes of trace minerals (serum iron, zinc, copper and magnesium) in thalassemia. 80 39

Zinc, copper, and magnesium concentrations in hair were measured in groups of children varying in one condition--protein-energy malnutrition, ricketts, thalassemia, malignancy, cardiac failure, or after prolonged infection and in healthy controls. As compared with controls, copper and magnesium concentrations were low in all groups, whereas higher values were obtained for hair zinc. These results showed that a generalized copper and magnesium deficiency were observed in the southeastern part of Turkey. However, zinc deficiency couldn't be detected as far as the hair zinc values were concerned, although all of the subjects fell within the 50 percentile limits for their age-appropriate weights and heights.
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PMID:Zinc, copper, and magnesium concentrations in hair of children from southeastern Turkey. 170 58

Beta-thalassemia/Hb E is a genetic disease prevalent in Thailand. This study has used atomic absorption spectroscopy to evaluate red cell and plasma calcium, copper and zinc in patients with beta-thalassemia/Hb E, both splenectomized and non-splenectomized. The levels of these trace elements in both red cells and plasma were different between the non-thalassemic controls and the disease patients. The most prominent result was that calcium concentration in red cells increased significantly in thalassemia subjects, particularly in splenectomized cases. These results might reflect the abnormal trace element metabolism and defects in the calcium transport system of the red cell membrane in thalassemia.
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PMID:Red cell and plasma calcium, copper and zinc in beta-thalassemia/hemoglobin E. 194 75

Three patients with rheumatoid disease were given the 'iron chelating' drug desferrioxamine (DFX), which also has an appreciable affinity for copper. The drug was injected cautiously, in lower doses than in patients with thalassaemia, and intramuscularly to evaluate its anti-inflammatory effects. Two of the three patients developed ocular abnormalities. One patient, who also received methyldopa, developed severe but reversible visual failure associated with an abnormal electro-oculogram (EOG); another showed reversible depression of the EOG. Analysis of the cerebrospinal fluid (CSF) of this patient showed an increase in phenanthroline detectable (non-caeruloplasmin-bound) copper. Analysis of the CSF of the third patient, who did not develop any clinical or electrophysiological ocular abnormalities, was normal. Haematological assessments indicated that all three patients probably had reduced iron stores. With in-vitro systems DFX was shown to mobilise copper from albumin and to facilitate copper movement across a cell membrane model, a property that was enhanced by methyldopa. Our observations are consistent with the concept that in rheumatoid patients low iron stores may result in binding of copper by DFX and that this may be of central importance in causing the ocular toxicity of DFX.
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PMID:Ocular toxicity of desferrioxamine--an example of copper promoted auto-oxidative damage? 278 62

The role of trace metals in the generation of free radical mediated oxidative stress in normal human red cells was studied. Ascorbate and either soluble complexes of Cu(II) or Fe(III) provoked changes in red cell morphology, alteration in the polypeptide pattern of membrane proteins, and significant increases in methemoglobin. Neither ascorbate nor the metal complexes alone caused significant changes to the cells. The rate of methemoglobin formation was a function of ascorbate and metal concentrations, and the chemical nature of the chelate. Cu(II) was about 10-times more effective than Fe(III) in the formation of methemoglobin. Several metals were tested for their ability to compete with Cu(II) and Fe(III). Only zinc caused a significant inhibition of methemoglobin formation by Fe(III)-fructose. These observations suggest that site-specific as well as general free radical damage is induced by redox metals when the metals are either bound to membrane proteins or to macromolecules in the cytoplasm. The Cu(II) and Fe(III) function in two catalytic capacities: (1) oxidation of ascorbate by O2 to yield H2O2, and (2) generation of hydroxyl radicals from H2O2 in a Fenton reaction. These mechanisms are different from the known damage to red cells caused by the binding of Fe(III) or Cu(II) to the thiol groups of glucose-6-phosphate dehydrogenase. Our system may be a useful model for understanding the mechanisms for oxidative damage associated with thalassemia and other congenital hemolytic anemias.
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PMID:Oxidative damage to human red cells induced by copper and iron complexes in the presence of ascorbate. 280 91

The plasma zinc and copper and urinary zinc levels were determined by an atomic absorption spectrophotometer technic in 14 patients with hemoglobin (Hb) H disease, 34 patients with beta-thalassemia/Hb E disease and 30 control subjects. Plasma zinc levels were lower and the plasma copper levels were higher in the patients than in controls. The plasma Cu:Zn ratios, a more valuable indicator of body zinc status, increased in the diseased subjects, indicating zinc deficiency. Higher urinary zinc levels in the both Hb H disease and 30 control subjects. Plasma zinc levels were lower and the plasma copper levels were higher in the patients than in controls. The plasma Cu:Zn ratios, a more valuable indicator of body zinc status, increased in the diseased subjects, indicating zinc deficiency. Higher urinary zinc levels in the both Hb H disease and 30 control subjects. Plasma zinc levels were lower and the plasma copper levels were higher in the patients than in controls. The plasma Cu:Zn ratios, a more valuable indicator of body zinc status, increased in the diseased subjects, indicating zinc deficiency. Higher urinary zinc levels in the both Hb H disease and beta-thalassemia/Hb E disease suggest that chronic hemolysis is responsible for hyperzincuria leading to zinc deficiency. The thalassemic patients with undergrowth had higher plasma Cu:Zn ratios than the patients with normal development, indicating a more severe zinc deficiency in the former.
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PMID:Zinc and copper status in hemoglobin H disease and beta-thalassemia/hemoglobin E disease. 681 76

Laser microprobe mass analysis (LAMMA) is an investigational method which is a powerful tool for the identification and quantitation of various elements present in small volumes of tissue. LAMMA is highly sensitive and capable of rapidly detecting concentrations of 1-3 p.p.m. of most metallic elements, in precisely localized cellular compartments. In order to further assess its value, cultured skin fibroblasts and biopsy tissues from human subjects and experimental animals were probed by LAMMA, and the results were correlated with ultrastructural findings. Biopsy samples were obtained from patients suffering from Gaucher disease, and from patients and animals with pathologic iron or copper metabolism. No significant abnormalities were detected in the cultured fibroblasts from patients with Gaucher disease, in contrast to the iron content of tissue biopsy Gaucher cells, which was markedly increased, apparently as a consequence of erythrophagocytosis. Particularly intense iron-related peaks were found in liver cytosiderosis due to neonatal or genetic haemochromatosis, thalassaemia major and in animal models of iron overload. An additional finding was the presence of aluminium accumulation in siderosomes of different cells. In liver biopsy samples from human Wilson's disease and from rats with an inherited disorder causing copper toxicosis, copper-containing compounds were identified and localized, and their relative concentration was estimated by LAMMA. The present study showed that LAMMA is a valuable technique for the localization and estimation of relative abundance of trace elements in various tissues containing excessive amounts of metals.
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PMID:The application of laser microprobe mass analysis to the study of biological material. 857 93

Serum zinc and copper levels were determined in 28 beta-thalassaemia and 15 sickle cell anaemia (SCA) patients of 3-10 years of age using atomic absorption spectrophotometry. The results were compared with 25 age-matched controls. Copper levels were significantly increased in beta-thalassaemia and sickle cell anaemia. Zinc levels were significantly increased in beta-thalassaemia but significantly decreased in SCA. The data suggest the occurrence of impaired kidney function and disturbance in the metabolism of zinc and copper in these patients.
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PMID:Serum zinc and copper levels in sickle cell anaemia and beta-thalassaemia in North Jordan. 868 4

Abnormal growth is a common feature of thalassaemia major in children. In an attempt to determine whether it has a nutritional cause, 12 children aged 1 to 3 years with thalassaemia major were studied under metabolic ward conditions. Nutritional status was assessed by anthropometry and biochemistry before and after an intensive nutrition regimen. Five children had wasting or stunting on admission. As a result of the nutrition intervention, mean weight for height improved significantly. The mean height increase of 0.4 cm after one month was not significant. Plasma zinc, depressed in half the children on admission, improved, as did alpha tocopherol, while copper decreased. Plasma insulin-like growth factor-I also increased commensurate with improved growth. Fat absorption was normal in all children. Undernutrition is an important cause of associated growth disturbances in children with thalassaemia major. Malnutrition was primarily caused by inadequate nutrient intake, as indicated by the capacity to gain weight appropriately when provided with nutrition support, and by the absence of intestinal malabsorption. While long term studies are required to determine if nutritional support will prevent stunting, these results underscore its central role in preventing nutritional deficiencies and in promoting normal growth in thalassaemic children.
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PMID:Nutritional factors and thalassaemia major. 878 27


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