Search PubMed⌕ Search

Biomedical subjects

G Forteleoni

Publications and source records attributed to G Forteleoni.

At least 37 records · Page 2Linked to original sources
PubMed1987

A case of ataxia telangiectasia with unbalanced glucose 6-phosphate dehydrogenase mosaicism in the granulocytic/monocytic lineages.

Ataxia telangiectasia is a genetically determined disease with multi-system abnormalities and a high incidence of neoplasia. In order to define the nature of the association between ataxia telangiectasia and malignancy, we investigated a patient with the disease and heterozygote for the Mediterranean variant of the X-linked marker glucose 6-phosphate dehydrogenase. Enzymatic mosaicism in hemopoietic and nonhemopoietic cells was evaluated with the 2-deoxy glucose 6-phosphate technique. While erythrocytes, platelets, and lymphocytes expressed the same double-enzyme phenotype as tissues of nonhemopoietic origin, granulocytes and monocytes expressed almost exclusively the Mediterranean-type enzyme. We suggest that, as the result of genetic instability at the hemopoietic stem-cell level, the granulocytic/monocytic progeny enjoyed a proliferative advantage and became the predominant clone.

Ataxia Telangiectasia↗
PubMed1985

Clonal development from a progenitor with restricted differentiative expression in acute lymphoblastic leukemia.

Three patients with acute lymphoblastic leukemia (ALL) and heterozygous for the Mediterranean variant of glucose-6-phosphate dehydrogenase (G6PD) have been investigated with the 2-deoxyglucose-6-phosphate (2dG6P) method to determine the number and type of progenitor cells in which the disease arose. A monoclonal origin was established for the lymphoblasts, while the other hemopoietic cell lines were not involved in the leukemic process.

Child↗
PubMed1985

Frequency and types of deletional alpha+-thalassemia in northern Sardinia.

We determined by restriction mapping the frequency of the -alpha 3.7 determinant in a random sample of 48 adults in Northern Sardinia. We found a frequency of 0.18 +/- 0.04 and demonstrated that only type I crossover as determined by Apa I digestion (Higgs et al. 1984) is present. Moreover, we showed that this haplotype is not associated with an Rsa I polymorphism 5' to the alpha 2-globin gene. These data support the hypothesis of a unique origin of this deletion in Sardinia.

Adult↗
PubMed1985

Impairment of the calcium pump of human erythrocytes by divicine.

Divicine (2,6-diamino-4,5-dihydroxypyrimidine), an aglycone implicated in the pathogenesis of favism, produces a remarkable and consistent inactivation of the Ca2+-ATPase activity of the erythrocyte calcium pump. The patterns of inactivation are similar in normal and glucose-6-phosphate dehydrogenase (G6PD)-deficient erythrocytes. Inactivation of Ca2+-ATPase is apparently unrelated to the cellular GSH system, to the proteolytic machinery of mature erythrocytes, and to calmodulin, and also occurs in hemoglobin-free, unsealed erythrocytes membranes at 50-100 microM concentrations of divicine. Analysis of erythrocytes that have escaped destruction during the acute hemolytic crisis of a number of favic patients revealed a dramatic elevation of erythrocyte calcium and a significant decrease of Ca2+-ATPase activity. These results support the view that divicine plays a toxic role in the pathogenesis of favism and suggest that acute electrolyte imbalances, mostly affecting calcium homeostasis, are involved in the mechanisms of erythrocyte damage and destruction in this hemolytic disease.

Calcium↗
PubMed1985

Favism: disordered erythrocyte calcium homeostasis.

The biochemical events that take place during acute hemolysis of G6PD-deficient subjects in favism are far from being elucidated. Evidence is here reported for a constantly and heavily disordered calcium homeostasis in the erythrocytes from seven favic patients. The abnormality, ie, a significantly impaired calcium ATPase activity and a parallel marked increase of intracellular calcium levels, was characteristic of the acute hemolytic crisis although unrelated to the attendant reticulocytosis. Concomitantly, a remarkable decrease of intracellular potassium was also observed. The mean +/- SD Ca2+-ATPase activity in the favic patients was 20.8 +/- 7.8 mumol Pi/g Hb/h compared with 37.2 +/- 8.5 in the matched controls represented by 12 healthy G6PD-deficient subjects (P less than .001). The mean +/- SD intraerythrocytic calcium content was 288 +/- 158 mumol/L of erythrocytes in the favic patients as compared with 22.0 +/- 8.2 in the G6PD-deficient controls (P less than .001). The intraerythrocytic potassium content was 76.6 +/- 19.3 mmol/L of erythrocytes in the favic patients and 106.6 +/- 8.2 in the G6PD-deficient controls (P less than .001). In vitro incubation of normal and G6PD-deficient erythrocytes with divicine, a pyrimidine aglycone present in fava beans and strongly implicated in the pathogenesis of favism, reproduces most of these events, including drop of calcium ATPase, increased intracellular calcium, and leakage of erythrocyte potassium.

Acute Disease↗
PubMed1984

Favism: a hemolytic disease associated with increased superoxide dismutase and decreased glutathione peroxidase activities in red blood cells.

Red blood cells of favism patients with acute hemolytic crisis have markedly more superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) and less glutathione peroxidase (glutathione:hydrogenperoxide oxidoreductase, EC 1.11.1.9) than either normal controls, glucose-6-phosphate dehydrogenase-deficient subjects or favism patients outside hemolytic crisis. This altered value of the two enzyme activities is not due to increased reticulocyte content of blood. The electrophoretic triplet pattern of superoxide dismutase is also changed, with significant increase of the most positively charged band. Similar modifications of the two enzyme activities are observed after treatment of normal red blood cells with high concentrations of divicine and ascorbate, which are redox compounds that are contained in fava seeds. This treatment produces no hemolysis, but leads to hemolysis if the treated cells are resuspended in the homologous plasma. These results suggest a possible role of active oxygen species in the development of favism.

Ascorbic Acid↗
PubMed1984

Favism: looking for an autosomal gene associated with glucose-6-phosphate dehydrogenase deficiency.

Favism is a severe, acute haemolytic anaemia which occurs in about 20% of G6PD deficient subjects after ingestion of fava beans. Since not all G6PD deficient subjects are sensitive to fava beans, the possibility has been suggested that extra erythrocytic factors may play an important role in the susceptibility to haemolytic favism. To test the hypothesis that an autosomal enzyme is involved in the pathogenesis of favism, we carried out a beta-glucosidase assay in small intestine biopsies from normal subjects and G6PD deficient subjects with or without favism. Beta-glucosidase might be involved in the absorption and metabolism of fava beans and a quantitative polymorphism could explain the different susceptibility to fava beans of G6PD deficient subjects. Our observation showed no consistent quantitative polymorphism of beta-glucosidase in the subjects examined.

Favism↗
PubMed1983

Neonatal hyperbilirubinaemia in heterozygous glucose-6-phosphate dehydrogenase deficient females.

Glucose-6-phosphate dehydrogenase (G6PD, D-glucose 6-phosphate: NADP oxidoreductase, E.C. 1.1.1.49) activity and the percentage of G6PD deficient erythrocytes was determined in 50 girls heterozygous for G6PD deficiency, 25 of whom had had hyperbilirubinaemia at birth and 25 who had normal bilirubin levels. The enzymatic activity was 2.32 +/- 0.87 I.U./g Hb in the first group and 3.31 +/- 0.92 I.U./g Hb in the second group. The percentage of G6PD deficient erythrocytes was 54.1 +/- 15.3 and 65.3 +/- 14.0, respectively. The level of enzymatic activity exceeded 4 I.U./g Hb and the percentage of G6PD deficient cells fell below 40% in only one of the subjects who had developed hyperbilirubinaemia. Levels of enzymatic activity below 4 I.U./g Hb, or percentages of G6PD deficient erythrocytes higher than 40% can therefore be considered to be associated with a high risk of developing neonatal hyperbilirubinaemia. In our opinion, these babies should receive prophylactic treatment with phenobarbital, as do G6PD deficient Mediterranean males.

Bilirubin↗
PubMed1983

Favism and hemolytic anemia in glucose-6-phosphate dehydrogenase-deficient subjects in North Sardinia.

The present paper reports the incidence from 1965 to 1979 of acute hemolytic anemia for a total of 948 cases in G-6-PD-deficient subjects due to the ingestion of fresh or dried fava beans or certain drugs and to viral infections. The highest percentage of hemolytic crises was due to fresh fava beans (94.4%). No cases of favism were observed in breast-fed babies whose mothers had eaten fava beans or from pollen inhalation. The male sex proved to be the hardest hit. Hemoglobin values were lower than or equal to 7 g/dl in about 75% of males and 50% of females. Total bilirubin values were lower than 103 mumol/l (6 mg/dl) in about 75% of males and 85% of females. Both the hemoglobin and bilirubin values were statistically significant. Mean transaminase values (SGPT) were significantly higher than those of normal controls. No correlation between favism and blood groups was found.

Anemia, Hemolytic↗
PubMed1983

Hemoglobin A1 in subjects with G-6-PD deficiency during and after hemolytic crises due to favism.

HbA1 was determined in 15 G-6-PD-deficient subjects during a hemolytic crisis with hemoglobinuria due to ingestion of fresh fava beans. The same G-6-PD-deficient subjects were studied again 4 months after the crisis, when they were asymptomatic. 15 normal healthy children served as controls. A statistically significant decrease in HbA1 was observed in the favic subjects during hemolytic crises compared with their values 4 months later and those of the control group.

Adolescent↗
PubMed1983

Reexpression of normal stem cells in erythroleukemia during remission.

A patient with erythroleukemia and heterozygous for the Mediterranean variant of the X-linked enzyme glucose-6-phosphate dehydrogenase (G6PD) was studied to determine the number and type of progenitor cells in which the disease arose. G6PD mosaicism was assessed by the different rate of utilization of 2-deoxy-glucose-6-phosphate (2dG6P) by normal and Mediterranean variants of G6PD. Erythroleukemia is established as a clonal disease involving a precursor cell common to the erythroid and myeloid lines. After intensive chemotherapy, restoration of nonmonoclonal hemopoiesis is achieved, as indicated by the reappearance of the mosaic phenotype in hemopoietic cell populations.

Aged↗