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N Vianelli

Publications and source records attributed to N Vianelli.

At least 37 records · Page 2Linked to original sources
PubMed1995

Brain MRI and SPET in thrombotic thrombocytopenic purpura.

We describe 5 cases of thrombotic thrombocytopenic purpura (TTP) with neurological manifestations. All of the patients underwent brain magnetic resonance imaging (MRI) following recovery; two underwent single photon emission tomography (SPET) during the acute phase of the disease. SPET showed reduced cerebral blood flow, whereas the results of brain MRI were normal in all patients. Plasma exchange (PE) treatment was promptly instituted in all cases. Our findings show that prompt treatment with PE may avoid permanent brain damage even when the neurological signs and symptoms are relate to brain ischemia.

Adult↗
PubMed1994

Vincristine sulfate for the treatment of thrombotic thrombocytopenic purpura refractory to plasma-exchange. The Italian Cooperative Group for TTP.

Among all the patients treated by the Italian Cooperative Group for TTP, we retrospectively reviewed the results obtained using vincristine (VCR) in 8 TTP patients (4 men and 4 women, average age: 39.25 years, range: 23-48) who did not respond to combined apheretic and pharmacologic treatment. All patients, after failing to respond to treatment, were started on VCR at the dose of 2 mg, i.v., once a week. Despite this treatment, 4 patients (50%) died 1, 7, 12 and 25 days after the first VCR dose, respectively. The other 4 patients who received VCR achieved complete remission 24, 30, 40 and 50 days from the beginning of the treatment. Total doses of VCR ranged from 2 to 6 mg in the decreased group, and from 6 to 14 mg in the cured patients. In our experience, VCR is a promising agent to treat TTP patients resistant to conventional plasma-exchange and pharmacologic therapy.

Adult↗
PubMed1993

Relief of intractable pruritus in polycythemia vera with recombinant interferon alfa.

Following reports that recombinant interferon alfa (rIFN alpha), besides inducing clinical and hematologic remission in polycythemia vera (PV), can also resolve intractable pruritus, we used rIFN alpha to treat 13 PV patients complaining of severe pruritus refractory to conventional treatment (venesection and/or cytostatics). rIFN alpha was administered intramuscularly three times a week at a dosage of 3.0 x 10(6) U. Eight patients (61.5%) reported a > or = 50% reduction of pruritus, which occurred within 2-8 weeks from the start of rIFN alpha treatment, leading to a substantial improvement in their quality of life. Three patients had to stop rIFN alpha within the first month of therapy because of unacceptable side effects. Thus rIFN alpha seems to be capable of providing considerable relief of otherwise intractable pruritus in a good proportion of PV patients.

Aged↗
PubMed1993

Recombinant alpha-interferon 2b in the treatment of HIV-related thrombocytopenia.

OBJECTIVE: To assess the efficacy and the mechanism of action of alpha-interferon (alpha-IFN) in the treatment of HIV-related thrombocytopenia. METHODS: Thirteen HIV-positive subjects [nine men and four women with severe thrombocytopenia (platelets, < or = 30 x 10(9)/l)] were treated with alpha-IFN 2b alone at a dose of 3 x 10(6) U three times a week for 5 weeks. Haematological parameters, platelet kinetic and bone-marrow myeloid progenitor cultures [megakaryocyte colony-forming units (CFU-MK); granulocyte macrophage CFU (CFU-GM) and erythroid burst-forming units (BFU-E)] were evaluated before and after treatment in responsive subjects. RESULTS: Seven out of 13 subjects showed a partial response (platelets, 50-149 x 10(9)/l) after alpha-IFN 2b therapy. Platelet survival as evaluated by 111In-oxine significantly increased, while platelet turnover showed a slight but not statistically significant increase after treatment. The growth of bone-marrow myeloid progenitor cells decreased after alpha-IFN 2b therapy, again without statistical significance. CONCLUSION: alpha-IFN 2b may increase the platelet count in HIV-positive subjects with severe symptomatic thrombocytopenia by prolonging platelet survival. The immunomodulatory and antiviral action of this drug may be responsible for prolonged platelet survival.

AIDS-Related Complex↗
PubMed1993

Increased serum levels of transforming growth factor beta-1 in patients affected by thrombotic thrombocytopenic purpura (TTP): its implications on bone marrow haematopoiesis.

In this study we evaluated the effect of serum collected from seven thrombotic thrombocytopenic purpura (TTP) patients, either in the acute phase of the disease or in clinical remission, on the in vitro growth of bone marrow haematopoietic progenitor cells, obtained from the same TTP patients in clinical remission and from normal donors. The addition to the cultures of autologous sera collected from TTP patients in acute phase of the disease showed a clear-cut dose-dependent inhibition of immature haematopoietic progenitor cells (BFU-E, CFU-meg and 14th day CFU-GM). On the other hand, no inhibitory effects were observed on more mature 7th day CFU-GM. Interestingly, also sera collected from TTP patients in clinical remission still maintained some inhibitory activity on the growth of immature progenitor cells. A similar inhibitory activity was noticed when TTP sera were tested on normal bone marrow haematopoietic progenitor cells. Such inhibitory activity was significantly reduced in blocking experiments by the addition of a polyclonal neutralizing anti-TGF-beta 1 antibody and the presence of increased levels of both bioactive and latent TGF-beta 1 in TTP sera was confirmed in a bioassay on CCL64 cells. These data contribute to explain the lack of a clear compensatory haematopoiesis observed in some patients with active TTP and add further evidence to the notion of the existence of a state of latent platelet activation in TTP patients in clinical remission.

Acute Disease↗
PubMed1993

Reduced responsiveness of bone marrow megakaryocyte progenitors to platelet-derived transforming growth factor beta 1, produced in normal amount, in patients with essential thrombocythaemia.

In this study we evaluated the amount of transforming growth factor-beta 1 (TGF-beta 1) in platelet lysates obtained from 12 patients affected by essential thrombocythaemia (ET) in comparison with five patients affected by myelofibrosis with myeloid metaplasia (MMM) and 15 healthy donors. The levels of both bioactive and latent TGF-beta 1, evaluated in a bioassay on CCL64 cells, before and after transient acidification, were similar in platelet lysates from ET patients and normal donors and significantly (P < 0.01) elevated in platelet lysates from MMM patients. Moreover, platelet lysates from ET patients and normal controls, showed a similar degree of colony suppression when tested on haematopoietic progenitor (CD34+) cells, purified from normal bone marrows, whereas platelet lysates from MMM patients showed a higher (P < 0.01) inhibitory activity on normal CFU-meg and BFU-E growth. In parallel, platelet lysates form ET patients and normal controls were tested on CD34+ cells, purified from ET bone marrows. ET bone marrow BFU-E, similarly to normal bone marrow BFU-E, were markedly inhibited by platelet lysates, whereas ET bone marrow CFU-meg were significantly (P < 0.05) less responsive to the inhibitory activity of platelet lysates than normal bone marrow CFU-meg. The main factor responsible for the inhibitory activity contained in platelet lysates was transforming growth factor-beta 1 (TGF-beta 1), as demonstrated by the ability of a polyclonal neutralizing anti-TGF-beta 1 antibody to almost completely reverse the suppressive effect of platelet lysates on CFU-meg and BFU-E growth. Our data demonstrate that the amount of intraplatelet TGF-beta 1 is similar in ET patients and normal controls, whereas it is increased in platelets from MMM patients. Moreover, megakaryocyte progenitors in ET show a reduced sensitivity to platelet-derived inhibitors and, in particular, to TGF-beta 1.

Blood Platelets↗
PubMed1993

Hypercoagulability in patients undergoing autologous or allogeneic BMT for hematological malignancies.

Severe thrombotic alterations, such as veno-occlusive disease of the liver, may occur in the early phase following high-dose chemoradiotherapy and BMT. In this study, performed in patients with hematological malignancies subjected to allogeneic (10 cases) and autologous (20 cases) BMT, we have monitored laboratory hemostatic parameters to better understand the pathogenetic mechanism of thrombosis and particularly of veno-occlusive disease. Prothrombin time, activated partial thromboplastin time, plasma fibrinogen, markers of hypercoagulability (thrombin-antithrombin complex and prothrombin fragment F1+2); natural anticoagulants (protein C, protein S and antithrombin) together with fibrinolytic parameters (plasminogen, alpha 2-antiplasmin, tissue-plasminogen activator, plasminogen activator inhibitor and D-dimer) were assessed before transplant, on day 0 and weekly for 1 month thereafter. A hypercoagulability state, not related to an impairment of the anticoagulant and fibrinolytic systems, was documented before and after autologous and allogeneic transplant. Two patients developed veno-occlusive disease: they did not show any difference from the other patients before transplant while they presented a decrease of the natural anticoagulants along with altered fibrinolytic parameters only at the clinical onset of veno-occlusive disease. In conclusion, in this study a state of marked hypercoagulability was documented in BMT patients and the hemostatic laboratory parameters evaluated were not able to predict the occurrence of the thrombotic complications.

Antithrombin III↗
PubMed1992

Recombinant interleukin-2 (rIL-2) in acquired immune deficiency syndrome (AIDS): preliminary report in patients with lymphoma associated with HIV infection.

In an ongoing phase II study, 12 patients with lymphoma and HIV infection were treated with zidovudine (ZDV) and recombinant interleukin-2 (rIL-2) to evaluate if this association may produce beneficial effect on the immunologic status and the outcome of lymphoma. The protocol included daily doses of rIL-2 at 6 MIU/m2 over 5 days in c.i. per week for a total 4 courses; ZDV was associated at 600 mg/d in the period under study. An improved CD4 count, exceeding 2- to 4-fold the basal count, was obtained in patients with a basal CD4 number greater than 100/microliters accompanied by a significant increase of NK and LAK activity (p less than 0.001). From the clinical point of view the reduction of tumor manifestation was proportional to CD4 basal number; 2 patients from those with CD4 greater than 100/microliters obtained a complete remission after rIL-2 and ZVD. The p24 antigen, taken as parameter of viral replication, remained invariably negative after rIL-2 and ZDV in patients already negative and became negative in 1 patient previously positive. Our conclusion is that the association of rIL-2 and AZT is safe and useful in patients with lymphoma and HIV infection.

CD4-Positive T-Lymphocytes↗
PubMed1991

Lack of compensatory megakaryocytopoiesis in HIV-1-seropositive thrombocytopenic individuals compared with immune thrombocytopenic purpura patients.

In this study we demonstrate that HIV-1-seropositive thrombocytopenic individuals, in contrast with immune thrombocytopenic purpura (ITP) patients, fail to have a compensatory increase of megakaryocytopoiesis. The in vitro growth of bone-marrow megakaryocyte progenitors (CFU-MK) and the production of granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-1 and IL-6 by bone-marrow mononuclear adherent cells and peripheral blood (PB) light-density mononuclear cells were studied in 12 HIV-1-seropositive thrombocytopenic individuals with respect to 12 ITP patients and 15 normal controls. In HIV-1-seropositive thrombocytopenic individuals, CFU-MK size (number of megakaryocytes per colony) was similar to normal controls but significantly lower (P less than 0.05) than in ITP patients. IL-1 and IL-6 production was similar in the three groups of subjects. On the other hand, GM-CSF production by bone-marrow mononuclear adherent cells in HIV-1-seropositive thrombocytopenic individuals was similar to normal controls but significantly (P less than 0.05) lower than in ITP patients, whereas GM-CSF production by PB light-density mononuclear cells was markedly (P less than 0.05) defective compared with both normal controls and ITP patients. The positive correlation between number and size of CFU-MK and production of GM-CSF by bone-marrow mononuclear adherent cells, observed in all three groups of subjects, demonstrates the central role of GM-CSF in the control of megakaryocytopoiesis.

Adult↗
PubMed1991

Platelet function and interferon alpha-2a treatment in essential thrombocythaemia.

The effects of interferon (IFN) alpha-2a treatment on platelet function were evaluated in 20 patients affected by essential thrombocythaemia (ET). Baseline data documented the well-known abnormalities of in vitro platelet aggregation and the constant presence of a delta-storage pool deficiency. The therapy in all patients reduced the platelet count, and in the majority of them caused a partial improvement of in vitro platelet aggregation. Although the mean intraplatelet ADP level improved during treatment, it always remained below the normal range documenting persistence of the delta-storage pool deficiency. The plasma beta-TG levels, which initially were high, significantly decreased during treatment, but the beta-TG ratio and the platelet beta-TG values always remained within the normal range--this suggests an absence of platelet activation either before or during therapy. Our results demonstrate that, despite significantly reducing the platelet count, IFN alpha-2a treatment only partially corrects the qualitative platelet abnormalities in ET.

Adenosine Diphosphate↗
PubMed1991

Ticlopidine lowers plasma fibrinogen in patients with polycythaemia rubra vera and additional thrombotic risk factors. A double-blind controlled study.

Thirty-seven patients affected by polycythaemia rubra vera (PRV) and with at least one additional thrombotic risk factor (overt vascular disease, diabetes mellitus, treated hypertension, smoking habit, plasma hyperviscosity, hyperfibrinogenemia) were enrolled in a double-blind randomized placebo-controlled study, and 18 were given ticlopidine 250 mg, b.i.d., for 60 days. All the patients had previously been submitted to cytoreduction, and PRV was under control in all cases at the start of the study. During the study, the haematological parameters were controlled every 15 days, and venesection was performed if haematocrit was greater than 46%. Whole blood viscosity, at low and high shear rates, plasma viscosity, and fibrinogen were measured on days 0 and 60. In the ticlopidine group, we recorded a significant 13.14% reduction of the mean fibrinogen level after treatment (390 +/- 63 vs. 449 +/- 97 mg/dl, p less than 0.01). All the other haemorheological parameters were not significantly modified by ticlopidine treatment, nor were there significant modifications recorded in the placebo group. Our study shows that ticlopidine may reduce a probable thrombotic risk factor (hyperfibrinogenemia) in PRV patients.

Aged↗
PubMed1990

Myelofibrosis with myeloid metaplasia: clinical and haematological parameters predicting survival in a series of 133 patients.

The prognostic value of 12 clinical and haematological parameters, recorded at diagnosis, in myelofibrosis with myeloid metaplasia (MMM) was retrospectively analysed in a consecutive series of 133 patients followed for a minimum of 60 months. Multivariate analysis showed that the following features were associated with a significantly shorter survival: (1) short period of time (less than 13 months) between first symptoms and diagnosis; (2) anaemia (haemoglobin less than 10 g/dl); (3) leucocyte count greater than 12 x 10(9)/l; (4) peripheral blood granulocyte precursors greater than 10%. Age, splenectomy and percentage of peripheral blood metamyelocytes were found significantly to affect survival only from univariate analysis, whereas sex, size of spleen, thrombocytopenia and thrombocytosis were of no prognostic significance. These data suggest that a more intensive chemotherapy might be useful for younger patients with bad prognostic factors at diagnosis.

Adult↗