The antiviral drug ribavirin (RBV) is widely used in combination with interferon (IFN) in the treatment of chronic hepatitis C virus (HCV) infection. A major side effect of RBV is a reversible hemolytic anemia. We have evaluated the in vitro effects of RBV on erythrocyte adenosine triphosphate (ATP) content and on hexosemonophosphate shunt (HMS). The ATP levels were significantly decreased in the presence of RBV and the HMS was increased, suggesting the presence of red cell susceptibility to oxidation. In vivo, we have studied the hematologic effects of treatment with RBV alone or in combination with IFN in 11 patients with chronic hepatitis C: 6 were treated with RBV (1,000-1,200 mg/d) and 5 were treated with a combination of RBV and IFN (5 million U thrice weekly). Patients were studied at semi-monthly intervals from 0 to day 60 of therapy. Both treatments were associated with a significant reduction in hemoglobin levels (steady state level at day 45) and a marked increase in absolute reticulocyte counts. Erythrocyte Na-K pump activity was significantly diminished, whereas K-Cl cotransport and its dithiotreitol-sensitive fraction, malondialdehyde and methemoglobin levels were significantly increased. RBV-treated patients showed an increase in aggregated band 3, which was associated with a significantly increased binding of autologous antibodies and complement C3 fragments indicating an erithrophagocytic removal by reticuloendothelial system. (HEPATOLOGY 2000;31:997-1004.)Hepatitis C virus (HCV) infection is a major cause of chronic liver disease, leading to cirrhosis, end-stage liver disease, and hepatocellular carcinoma worldwide. 1,2 A major therapeutic goal in HCV-infected patients is to achieve early eradication of the virus, and to prevent severe long-term clinical complications. Interferon alfa (IFN-␣) is currently the only therapy that has been shown to have beneficial effects in chronic hepatitis type C. However, with a standard regimen of 3 million U administered 3 times per week for 6 to 12 months, only a small fraction of approximately 15% to 20% of the patients showed a sustained response with normalization of serum alanine transferase levels and serum HCV-RNA clearance. 3 Ribavirin (1-␤-D-ribofuranosyl-1H-1, 2,4-triazole-3-carboxamide) (RBV) is a water soluble synthetic guanosine analog that exerts antiviral activity against DNA and RNA viruses after intracellular phosphorylation. 4 Current studies indicate that combination therapy with RBV and IFN is associated with higher rates of sustained virological, biochemical, and histological response compared to IFN monotherapy. [5][6][7][8][9][10] The major side effect of RBV treatment is the occurrence of a reversible hemolytic anemia in a substantial proportion of treated patients. 11 The underlying mechanism is unknown. Studies on steady-state pharmacokinetics of RBV have shown that erythrocyte concentration of RBV greatly exceeds plasma concentrations 12 and that RBV is a transported permeant for the (es) nucleoside transporter in human erythrocytes...

Background: Basophils are circulating cells involved in hypersensitivity reactions and allergy but many aspects of their activation, including the sensitivity to external triggering factors and the molecular aspects of cell responses, are still to be focused. In this context, polychromatic flow cytometry (PFC) is a proper tool to investigate basophil function, as it allows to distinguish the expression of several membrane markers upon activation in multiple experimental conditions.

Summary. The membrane complex a IIb b 3 is the major receptor for fibrinogen and is involved in platelet adhesion and aggregation. Evidence has been presented that the Pl A2 allele of the b 3 Pl A1/A2 gene polymorphism might be an independent risk factor for coronary thrombosis, but the matter is still controversial. We investigated the relationship between this polymorphism and possible alterations of platelet functions in vitro. The platelet adhesion to fibrinogen-coated microplate wells and the aggregation induced by several different agonists were tested in 63 healthy volunteers, among them, 49 subjects with Pl A1/A1 polymorphism, 12 subjects with Pl A1/A2 polymorphism and two subjects with Pl A2/A2 polymorphism. Subjects with Pl A1/A2polymorphism or with Pl A2/A2 polymorphism showed significantly lower platelet responses as compared with Pl A1/A1 subjects when either arachidonic acid or the thromboxane A 2 analogue, U46619, were used as agonists.In resting condition and after thrombin or ADP stimulation, platelet function was normal in all the subjects. An increased sensitivity to the anti-aggregatory effect of acetylsalicylic acid was observed in platelets from subjects with the Pl A2 allele. Finally, using a flow-cytometric evaluation and determining the b-thromboglobulin plasma levels, we did not find any evidence of a Pl A2 platelet hyperreactivity ex vivo. Our findings are not consistent with the hypothesis that the purported increase of cardiovascular risk in these subjects may be as a result of platelet hyperactivation. On the contrary, the Pl A2 allele is associated with a platelet functional deficiency, specifically linked to the activation of the fibrinogen receptor by thromboxane A 2 .

On the basis of a previous experience suggesting that daunorubicin dose in induction was an independent prognostic factor in adult ALL, we designed a chemotherapeutic regimen (ALLVR589) characterized by high doses of daunorubicin (270 mg/m2) in induction and by high-dose Ara-C in post-remission. The protocol was otherwise conventional: induction and post-remission therapy were followed by chemo-radio prophylaxis of the central nervous system (CNS) and periodical reinductions over a 3-year maintenance period. Sixty consecutive patients (male 42, female 18, median age 34 years, range 14-71; B-lineage, 35; T-lineage, 25; Ph' and bcr/abl positive, 7) recruited between 1989 and 1996, were evaluated for treatment outcome. Complete remissions were 56 (93%), one patient had refractory disease, early deaths were five (8%); 19/56 (34%) patients relapsed, five of whom were Ph'+. Median time to relapse was 11 months (range 3-47); 68% of relapses occurred within 12 months from CR. No CNS relapses were observed. After a median follow-up of 44 months (1-100), 33/60 (55%) patients remain event-free; 23/60 (38%) are off-therapy in continuous CR (median follow-up from diagnosis: 63 months; range 38-100). These results suggest that increasing DNM dosage in induction is one of the possible approaches to improve the outcome of adult ALL by decreasing the relapse occurrence.

Many authors have recently found a positive correlation between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP), the most common autoimmune hematological disorder. In order to clarify the pathogenic mechanism of H. pylori-associated ITP, we have investigated 52 consecutive ITP adult patients for Helicobacter pylori infection, B- and T-cell clonality and HLA class II alleles. Thirty-four ITP patients (65.4%) were infected by H. pylori and bacterium eradication was accompanied by a long-term platelet response in 17 (53.1%) of them. A B-cell clonality was found in three patients (5.8%, two patients H. pylori-negative and one patient H. pylori-positive). The ITP patients with H. pylori infection showed a HLA-DRB1*11, *14 and -DQB1*03 frequencies significantly higher and a -DRB1*03 frequency significantly lower than in H. pylori-negative patients. Moreover, an HLA-DQB1*03 pattern was associated with a higher probability of platelet response to eradication treatment. If our study documents the efficacy of eradication treatment in H. pylori-infected ITP patients, it may also help to identify different subgroups of ITP patients with probably different pathogeneses of thrombocytopenia and, finally, different responses to eradication treatment.

Our study shows that phlebotomies are a safe and effective method for reducing iron over-load in multiply transfused long-term AL survivors with secondary hemochromatosis.

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A literature review reports increased erythrocyte indices [hemoglobin concentration, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin (MCH), MCH concentration] in subjects with hereditary hemochromatosis (HH). We, therefore, screened 52 consecutive patients with polycythemia vera for 12 HH gene mutations, comparing iron status and red cell parameters between patients positive or negative for HH gene mutations. Our results support the evidence that there is no association between these two conditions.