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G Graziadei

Publications and source records attributed to G Graziadei.

11 recordsLinked to original sources
PubMed2001

Membrane-bound iron contributes to oxidative damage of beta-thalassaemia intermedia erythrocytes.

Iron-dependent oxidative reactions in beta-thalassaemic erythrocyte membranes are involved in premature cell removal and anaemia. We studied 22 beta-thalassaemia intermedia patients (i) to assess if membrane iron accumulation influences the oxidative damage to thalassaemic cells, and (ii) to see whether the mechanisms of haemoglobin destabilization described in vitro have indicators in circulating erythrocytes. Serum non-transferrin-bound iron as potentially toxic iron for erythrocytes was also evaluated. Membrane-bound free iron significantly correlated to bound haemichromes, suggesting a causal relation, but was poorly related to serum non-transferrin iron, which seems to contribute little to damage from outside the cells. The spleen played an important role in the removal of cells with more membrane iron.

Adult↗
PubMed2000

Oral isobutyramide therapy in patients with thalassemia intermedia: results of a phase II open study.

A pilot phase II open study on 12 patients with thalassemia intermedia (7 men, 5 women; age 31 +/- 2.0 years SE) treated with oral isobutyramide, a derivative of butyric acid (150 mg/kg body wt/day), was performed in order to evaluate the effect of this compound in stimulating hemoglobin F (HbF) production. No patient underwent blood transfusion in the 1-year time frame prior to the study. Nine patients were splenectomized. Safety was monitored by clinical and laboratory tests. Efficacy was assessed in terms of the non-alpha/alpha globin chain biosynthetic ratio and the percentage increase of HbF. The study design consisted of a screening phase, a treatment phase of 28 days, and a posttreatment follow-up of 28 days. All patients completed the study. Compliance to treatment was 100%. No drug-related adverse event was recorded. We observed little or no increase in the non-alpha/alpha ratio in the majority of patients. Six patients showed a percentage increase of HbF at the end of treatment and in 5 of those 6 further increases at the end of the follow-up period were observed. The change in percentage of HbF over time was close to significance both in the treatment period (P = 0. 06) and in the follow-up period (P = 0.08). These results indicate that butyrate derivatives can stimulate fetal hemoglobin in patients with intermediate thalassemia. Testing of the effects of different schedules of administration of isobutyramide will be required in order to determine the optimal use of this compound in the treatment of the beta-thalassemia syndromes.

Administration, Oral↗
PubMed1999

Metabolic indicators of oxidative stress correlate with haemichrome attachment to membrane, band 3 aggregation and erythrophagocytosis in beta-thalassaemia intermedia.

Haematological data, genotype, transfusion requirements, metabolic indicators of oxidative stress (flux via hexose-monophosphate shunt (HMPS); steady state level of GSH and GSSG, NADPH and NADP; activity of anti-oxidant enzymes), parameters of membrane damage (aggregated band 3; membrane-bound haemichromes, autologous immunoglobulins (Igs) and C3 complement fragments) and erythrophagocytosis were measured in erythrocytes (RBC) of 15 beta-thalassaemia intermedia patients (nine splenectomized) with low, if any, transfusion requirements. Patients presented increased aggregated band 3, bound haemichromes, Igs and C3 complement fragments, and increased erythrophagocytosis. Bound haemichromes strongly correlated with aggregated band 3. Anti-band 3 Igs were predominantly associated with aggregated band 3. Erythrophagocytosis positively correlated with aggregated band 3, haemichromes and Igs, suggesting the involvement of haemichrome-induced band 3 aggregation in phagocytic removal of beta-thalassaemic RBC. Splenectomized patients showed higher degrees of membrane damage and phagocytosis, significantly higher numbers of circulating RBC precursors, and tendentially higher numbers of reticulocytes. Basal flux via HMPS was increased twofold, but HMPS stimulation by methylene blue was decreased, as was the glucose flux via HMPS. GSH was remarkably decreased, whereas NADPH was increased. Except for unchanged catalase and glutathione reductase, anti-oxidant enzymes had increased activity. Negative correlation between HMPS stimulation by methylene blue and bound haemichromes indicated that the ability to enhance HMPS may counteract haemichrome precipitation and limit consequent membrane damage leading to erythrophagocytosis.

Adult↗
PubMed1998

Butyrate trials.

The aims of this study were to ascertain tolerability, safety and efficacy of oral isobutyramide (150 mg/kg bw/day) in stimulating fetal hemoglobin production in twelve thalassemia intermedia patients. Patients were treated for 28 days and followed for a further 28 days. Efficacy was monitored by non-alpha/alpha globin chain ratio and percentage of HbF. Five patients experienced increases of non-alpha/alpha ratio ranging between 5.3 and 100% at the end of treatment. Five patients show an increase of HbF ranging between 4.4 and 26%. Their HbF% continues to increase during follow-up period. The analysis of variance for HbF showed a time effect close to significance both in treatment period (p = 0.06) and in follow-up period (p = 0.08). Moreover, to evaluate a possible erythropoietic modification, serum Erythropoietin (sEpo) and serum Transferrin Receptor (sTfR) were evaluated. Serum Epo and sTfR levels were significantly increased during treatment (p < 0.05 vs baseline).

Adult↗
PubMed1998

Low-grade MALT lymphoma involving multiple mucosal sites and bone marrow.

Mucosa-associated lymphoid tissue (MALT) lymphomas are indolent neoplasms which tend to remain localized for a long time before spreading. We describe here the case of a 36-year-old woman with a low-grade MALT lymphoma involving the lung, stomach, lingual tonsil, and bone marrow at the time of diagnosis. The clonal origin of the pulmonary and bone marrow neoplastic infiltrates was assessed by means of gene rearrangement analysis. All of the involved sites were infiltrated by centrocyte- and monocytoid-like cells expressing the B-cell-associated antigens CD19 and CD20 and showed IgM lambda chain restriction; no CD5, CD10, or CD43 expression was detectable. As the patient had a history of recurrent bronchitis, and computed tomography performed 3 years before the lymphoma diagnosis had already revealed a lesion of the left lung, we conclude that the present case probably represents a pulmonary low-grade MALT lymphoma characterized by an early and unusual involvement of different mucosal sites and bone marrow.

Adult↗
PubMed1998

Plasmablastic lymphoma of the stomach. A case report.

We report the case of a 53 year-old woman with a gastric tumor showing morphological, phenotypical and molecular features of a plasmablastic lymphoma, a recently recognized subtype of diffuse large B-cell lymphoma. The tumor was composed of plasmablast-like cells, lacked CD45 and B-cell associated antigens, expressed the plasma cell-associated antigen CD38, and showed clonally rearranged IgH genes in the absence of bcl-2 and bcl-6 genes rearrangement.

Female↗
PubMed1998

The effect of dietary magnesium supplementation on the cellular abnormalities of erythrocytes in patients with beta thalassemia intermedia.

BACKGROUND AND OBJECTIVE: Reduced serum or erythrocyte Mg have been reported in human beta thalassemia. These deficiencies may play a role in the cellular abnormalities characteristic of this disorder. We have therefore studied the effect of dietary Mg supplementation in patients with beta thalassemia intermedia in order to establish whether it improves the abnormalities of thalassemic erythrocytes. DESIGN AND METHODS: Plasma and erythrocyte Mg were determined in 11 patients with b thalassemia intermedia, not requiring chronic transfusion therapy, and in 17 normal controls. Inclusion criteria included normal renal and liver function and performance status of 70% or greater. Seven patients were enrolled for the Mg supplementation study, after the appropriate informed consent was obtained. They were given a starting dose of 0.6 mEq/kg/day of magnesium pidolate, divided into two oral daily doses, for four weeks. In a 70-kg subject, a daily Mg dose of 42 mEq corresponds to 504 mg of Mg, with the daily Mg intake of normal subjects being 418 +/- 120 mg for males and 343 +/- 94 mg for females. After 28 days of treatment, five of the patients continued the protocol with a daily dosage increased to 1.2 mEq magnesium pidolate/kg/day, divided into two oral administrations, for an additional four weeks. RESULTS: In patients with untransfused beta thalassemia intermedia we found reduced erythrocyte Mg (in mmol/kg Hb, 6.12 +/- 1.5, n = 11 vs. 8.69 +/- 0.89, n = 17, respectively, p < 0.0001) and normal serum Mg. In the seven patients given oral Mg supplements, at Mg dosages of 0.6 mEq/kg/day we observed significant increases in erythrocyte Mg, and significant improvement in some of the characteristic abnormalities of beta that erythrocytes (increased Na-K pump, KCl cotransport, cell dehydration, increased osmotic resistance). These changes were maintained in the 5 patients who were treated with 1.2 mEq of Mg/kg/day. Follow-up studies showed a return to baseline conditions. There were no signs of Mg toxicity, with the only side effect being diarrhea, which was generally mild, but led to discontinuation for one patient after the first four weeks. INTERPRETATION AND CONCLUSIONS: These data indicate that dietary Mg supplementation improves some of the characteristic cellular function abnormalities of b thalassemia intermedia. The possible therapeutic value of this strategy should be further tested in these patients.

Biological Transport, Active↗
PubMedDate not supplied

Serum erythropoietin and circulating transferrin receptor in thalassemia intermedia patients with heterogeneous genotypes.

BACKGROUND: Thalassemia intermedia patients usually do not require blood transfusions; however, all show variable degrees of erythropoietic marrow expansion to compensate for more or less marked anemia, and this represents the major cause of complications in untransfused individuals. MATERIALS AND METHODS: To assess the degree of erythropoietic expansion in thalassemia intermedia, serum erythropoietin (sEpo) and serum transferrin receptor (sTfr) were determined in thirty Italian patient's characterized by their beta-globin genotype. RESULTS: Six patients showed inappropriately low sEpo levels (O/P ratio < 0.85). Even excluding these cases, no clear relationship was observed between Hb levels and sEpo or sTfr. Two groups of patients were compared: the first with low HbF (< 40%) that included the majority of beta(+) genotypes, and the second with high HbF (> 40%) that contained a prevalence of beta(0) genotypes. Hb levels were similar in the two groups: 8.09 +/- 1.15 g/dL in low HbF and 8.82 +/- 1.28 g/dL in high HbF patients. Mean sEpo was 112 +/- 78.02 mU/mL (O/P ratio = 0.98 +/- 0.22) in the first and 246.62 +/- 184.30 mU/mL (O/P ratio = 1.25 +/- 0.30) in the second group, with a statistically significant difference, as expected, because of HbF oxygen hyperaffinity. No significant difference in sTfr levels was observed, indicating a comparable erythropoietic response in the two groups. CONCLUSIONS: The relationships between anemia, HbF and total erythropoiesis in thalassemia are more complex than expected. Further studies of subjects with high HbF and benign conditions, such as HPFH, could be of help in clarifying this point, to the aim of safely increasing HbF in thalassemia intermedia.

Adult↗