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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lateral X-ray pictures of the skull in certain several and chronic disorders of the blood as thalassaemia, congenital haemolytic anaemia, sickle cell anaemia and iron deficiency disease show frequently changes of the outlines of the cranial bones. They consist of a double contour of the outer cranial border and on the interior side below the sagittal sutura of a band-like shadow or of multiple stripes and lines running parallel to the carnial vault. They concern the parietal bones and may extend from the bregma till to the lamda or occupy only a part of this distance. The roentgenological features are due to the enlargement of the crainal bones, the bulging out of both parietal bondes, the sometimes enlarged and deepened borders of the sulcus sagittalis superior and particularly to the furrow and depression on the skull above the sagittal suture caused by the protruding parietal bones on both sides. As these different abnormal structures must be passed by the picturing X-ray, effects of superposition and interference are produced. Longitudinal ridges or bony edges which could explain the roentgenological findings could not be established. Since the peculiar alterations of the cranial bones are mainly found in the mentioned blood disorders, where they are caused by the overgrowing red marrow, they also display the same roentgenological features. These features are, therefore, a characteristic sign of these diseases.
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PMID:[Double contours and companion shadows in the skull associated with anaemias (author's transl)]. 15 80

A subject of this investigation is the results of the subtotal examination of 4 villages for the detection of heterozygous beta-thalassemic carriers. 848 persons (55.5% of the registered population) have been examined. The mean frequency of the beta-Th gene was 0.0159, FST-Wahlund--0.00975. Statistically significant differences in the gene frequencies between villages have been revealed (p less than 0.01). The study of genetic distances (by Edwards) has revealed no intertribe differences in gene frequencies. The comparison of findings of the present study with other similar investigations enabled to account for the detected differences in the frequencies of beta-thalassemia as a result of the genetic drift. The importance of choosing populations for the study and methods for detection heterozygous beta-thalassemia are discussed.
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PMID:[Medical genetic study of the population of Uzbekistan. V. The frequency of heterozygous beta-thalassemia in 4 kishlaks of Urgut District, Samarkand Province]. 15 29

The inhabitants of 7 isolated villages (of different nationalities) and of 5 panmictic populations were studied. Populational and segregation analyses of Hb A2 in 3036 normal and 150 heterozygous individuals for beta- and delta beta-thalassemia were carried out. The Hb A2 levels in some populations are established to deviate from the normal distribution. Bimodal dependency of the levels of Hb A2 distribution is demonstrated, which suggests the existance of heterogenous subpopulations by the Hb A2 level. The segregation analysis has revealed distinct genetic determination of Hb A2 levels. There was a good correlation between Hb A2 and Hb F values (r=-0.82).
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PMID:[Population analysis of minor hemoglobin fractions. I. Hemoglobin A2]. 16 Mar 56

Left ventricular performance was studied in 23 young patients with severe chronic anemia due to beta-thalassemia major and intermedia. The patients were divided into three groups according to the number of blood transfusions they had received. The left ventricle (LV) was enlarged in patients who had not received blood and larger still in patients who had received multiple transfusions. Echocardiography and systolic time interval measurements showed that systolic function of the LV was good in all the patients and that there was no statistical difference in systolic function in patients who had and those who had not received multiple transfusions. Heart rate was increased in the latter group. Stroke index and cardiac index were high, especially in patients in Group 3. The diastolic closure rate (EF slope) of the anterior mitral leaflet and its amplitude of movement were increased, but less so in Group 3; this may reflect an alteration in diastolic LV distensibility. The results indicate that despite the presence of cardiomegaly and severe clinical congestive heart failure, LV performance is well preserved in patients with beta-thalassemia, even in those who have received repeated blood transfusions. Clinical cardiac failure is the consequence of volume overload and abnormal chamber compliance. There was no evidence in this of a congestive cardiomyopathy.
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PMID:Left ventricular function in beta-thalassemia and the effect of multiple transfusions. 16 23

A high percentage of Greek children with homozygous b-thalassemia were short and had a lag in growth, though some severely affected attained normal height. Bone age lagged significantly behind the chronologic age, even in those with normal height for their age. A longitudinal study demonstrated an initial normal growth velocity which decreased after the age of six for males and eight for females. No patient had a spurt of growth at adolescence. Height gain continued up to the age of 21 and then ceased. Statistical analysis with a multiple regression equation showed a significant relationship between the age and height of the patients. Low hemoglobin levels and severity of the disease seemed to hinder normal growth, but neither relationship was statistically significant.
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PMID:Stature and longitudinal growth in thalassemia major. A study of 229 Greek patients. 16 11

Interaction of acetylphenylhydrazine with oxyhemoglobin A in a hemolysate or in intact red cells resulted in the formation of ferrihemochromes as shown by a characteristic optical spectrum. The same optical spectrum was observed in a suspension of red cell ghosts containing numerous Heinz bodies. Electron paramagnetic resonance of actylphenylhydrazine-incubated red cells disclosed the presence of previously identified reversible ferrihemochromes, which can be reduced to functional hemoglobin, and irreversible ferrihemochromes, which cannot be reduced to functional hemoglobin. (Ferrihemochromes are defined as low spin forms of ferric hemoglobin having heme ligands endogenous to the protein structure). In contrast, only irreversible ferrihemochromes could be observed in ghosts containing Heinz bodies. In addition both optical and magnetic features of sulfhemoglobin were observed in an acetylphenylhydrazine-treated red cell hemolysate. Similar optical features are produced by the interaction of aromatic nitrogen-containg reductants with purified oxyhemoglobin in the presence of (NH4)2S. This reaction is not effected by the presence of catalase, suggesting that H2O2 is not an intermediate of the reaction. It is concluded that the mechanism of action of acetylphenylhydrazine with oxyhemoglobin is two-fold, ultimate reduction to high spin ferric hemoglobin followed by ferrihemochrome formation. Thus it appears that the pathway of denaturation of hemolytic anemias and thalassemia or induced by chemical reagents, entails a common route involving the formation of ferric hemoglobin by a reductive mechanism, followed by reversible ferrihemochromes, irreversible ferrihemochromes, and ultimately, precipitation.
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PMID:The demonstration of ferrihemochrome intermediates in heinz body formation following the reduction of oxyhemoglobin A by acetylphenylhydrazone. 16 36

Pituitary, adrenal, and pancreatic functions were investigated in 9 patients with thalassaemia major. 9 a.m. plasma ACTH values were 148-480 pg/ml (normal range 15-70 pg/ml). Cortisol and growth hormone response to insulin-induced hypoglycaemia was normal in all. 24-hour urinary excretions of 17-ketosteroids and 17-hydroxycorticosteroids were normal. There was normal cortisol response to intramuscular injection of ACTH. In a physiological adrenal stimulation test there was a significantly smaller response to each physiological dose of tetracosactrin. 4 patients had diabetic glucose tolerance tests--none are clinically diabetic. The mean plasma glucose utilization constant (Kgl=2-02) is significantly smaller than normal. Plasma insulin response both in the oral and the intravenous glucose tolerance test was significantly smaller than normal. The data were consistent with severe and widespread impairment of endocrine function and a plausible explanation would be iron deposition in endocrine organs. It is suggested that pituitary hyperfunction of ACTH secretion is due to target organ unresponsiveness which can be shown in its early stages only by a physiological test of the adrenal cortex. Skin pigmentation in thalassaemia seems to be due to the melanophore-stimulating effect of this raised plasma ACTH.
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PMID:Endocrinopathy in thalassaemia major. 18 88

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

The existence of frequent hemoglobin abnormalities raises a Public Health problem in Algeria. The presence of genes for hemoglobin S, hemoglobin C and thalassemia in various regions of the country causes severe congenital hemolytic anemias: thalassemia, sickle-cell anemia, S thalassemia, association of HbS and HbC. These diseases are often invaliding requiring frequent admissions to hospital and have a high social cost. We have also observed certain rare hemoglobins, of which some, hemoglobin Setif, hemoglobin D Ouled Rabah were described for the first time in Algerians. They are not pathogenic in the heterozygous state.
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PMID:[Abnormal hemoglobins in Algeria]. 19 6

These first cases of hemoglobinosis H show that alpha-thalassemia is not a simple curiosity in this part of the Western Mediterranean. They are not localised to a single part of Algeria as the areas from which the patients came were more than 150 km apart. They suggest that the enquiry should be continued by other means to determine the prevalence and pathological incidence.
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PMID:[1st cases of alpha-thalassemia in Algeria: 12 cases of hemoglobinosis H]. 19 7


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