Evaluation of platelet turnover by flow cytometry.

The number of circulating newly produced platelets depends on the thrombopoietic capacity of bone marrow as well as platelet removal from the bloodstream. Flow cytometric analysis with thiazole orange (TO), a fluorescent dye that crosses platelet membranes and binds intracellular RNA, has been used to measure circulating reticulated platelets (RPs) with high RNA content as an index of platelet turnover. We first assessed the specificity of TO flow cytometry and then applied this method in the diagnosis of thrombocytopenia caused by impaired platelet production or increased destruction.

Analysis of B- and T-cell clonality and HLA class II alleles in patients with idiopathic thrombocytopenic purpura: correlation with Helicobacter pylori infection and response to eradication treatment.

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.

VEPEMB in elderly Hodgkin's lymphoma patients. Results from an Intergruppo Italiano Linfomi (IIL) study.

Background: In advanced age the prognosis of Hodgkin's lymphoma (HL) is poor, but, as a consequence of the low incidence of HL in the elderly, prospective studies are lacking and the best treatment strategy is difficult to define.

Patients And Methods: One-hundred and five HL patients over 65 years of age were treated homogeneously with an original reduced-intensity regimen designed for HL in the elderly containing vinblastine, cyclophosphamide, procarbazine, etoposide, mitoxantrone and bleomycin (VEPEMB). Forty-eight early stage (IA-IIA) patients received three courses of VEPEMB followed by involved field irradiation.

Serum levels of soluble CD30 improve International Prognostic Score in predicting the outcome of advanced Hodgkin's lymphoma.

Background: The International Prognostic Score (IPS) and circulating levels of the soluble form of CD30 molecule (sCD30) have both been associated with poor outcome in patients with advanced Hodgkin's lymphoma (HL). The aim of this study was to assess the prognostic power of the combined evaluation of sCD30 and IPS in these patients.

Patients And Methods: We included 101 patients with advanced HL, treated with ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) or MOPP (mechlorethamine, vincristine, procarbazine and prednisone)/ABVD chemotherapy with or without radiotherapy.

Effects of sodium selenite on in vitro interactions between platelets and endothelial cells.

Selenium is an essential component of glutathione peroxidase enzymes, which protect cells against peroxidation and control concentrations of intracellular proxides. Since selenium deficiency is associated with an increased incidence of arterial thrombosis, we studied the effect of selenium on in vitro interactions between platelets and endothelial cells. Platelets from normal volunteers on a diet with (PLTSe+) or without (PLTSe-) selenium supplementation and human umbilical vein endothelial cells cultured in medium alone (ECSe-) or supplemented with Se (ECSe+) were used.

Improved prognosis of Pseudomonas aeruginosa bacteremia in 127 consecutive neutropenic patients with hematologic malignancies.

Objectives: Although decreasing in frequency, Pseudomonas aeruginosa bacteremia is still a major challenge for neutropenic cancer patients. In patients with hematologic malignancies, the prognosis of P. aeruginosa bacteremia is particularly poor due to the prolonged and severe neutropenia, mucosal damage, and other defects in immunity related both to the underlying disease and to the cytotoxic therapy.

The Italian Consensus Conference on Diagnostic Criteria for Myelofibrosis with Myeloid Metaplasia.

The purpose of this work was to develop a definition of myelofibrosis with myeloid metaplasia (MMM) using diagnostic criteria that would remain valid within the set of patients with chronic myeloproliferative disorders or myelodysplastic syndromes. A list of 12 names for the disease and 37 diagnostic criteria were proposed to a Consensus Panel of 12 Italian experts who ranked them in order so as to identify a core set of criteria. The Panel was then asked to score the diagnosis of 46 patient profiles as appropriate or not appropriate for MMM.

Serum levels of p55 and p75 soluble TNF receptors in adult acute leukaemia at diagnosis: correlation with clinical and biological features and outcome.

The tumour necrosis factor (TNF)/TNF-receptor (TNFR) complex plays a role in the growth of leukaemic cells. We retrospectively investigated the relationship between pretreatment serum concentration of soluble TNFR (p55- and p75-sTNFRs) and outcome in adult acute myeloid (AML 82 cases) and lymphoid (ALL 44 cases) leukaemia. Both sTNFRs were significantly higher in AML (p55-sTNFR 4.

Estimated 6-year event-free survival of 55% in 60 consecutive adult acute lymphoblastic leukemia patients treated with an intensive phase II protocol based on high induction dose of daunorubicin.

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.

Eighty-one percent event-free survival in advanced Burkitt's lymphoma/leukemia: no differences in outcome between pediatric and adult patients treated with the same intensive pediatric protocol.

Background: Advanced Burkitt's lymphoma (BL) has an extremely poor prognosis in adults. With a previous protocol including CNS prophylaxis, 40% of our adult patients achieved CR and only 13% became long survivors. In 1988, following this poor experience, we adopted a very intensive pediatric-derived protocol.

Preferential release of high amounts of interleukin-8 by myeloid blasts showing monocytic differentiation.

Background: In myeloid blasts, the expression and release of the multifunctional chemokine IL-8 could be expected to be differentiation-associated.

Methods: We investigated the profile of interleukin-8 (IL-8) expression and release by leukemic cells obtained at diagnosis from 42 untreated adult patients with acute myeloid leukemia of various FAB subtypes (2 M0, 7 M1, 6 M2, 6 M3, 10 M4 and 11 M5). IL-8 transcripts were evaluated by Northern blot and densitometric analysis.

Selenium enhances glutathione peroxidase activity and prostacyclin release in cultured human endothelial cells. Concurrent effects on mRNA levels.

Selenium (Se) is an essential component of glutathione peroxidase (GSH-Px), an enzyme that protects cells by reducing intracellular peroxides. Impaired Se status and GSH-Px activity seem associated with increased risk of atherosclerotic vascular diseases. This study reports the effects of Se supplementation on GSH-Px activity, on prostacyclin (PGI2) production, on 12-hydroxy-eicosatetraenoic acid (12-HETE) levels, and on GSH-Px mRNA expression in cultured human umbilical vein endothelial cells (HUVEC).

Serum levels of soluble CD30 are elevated in the majority of untreated patients with Hodgkin's disease and correlate with clinical features and prognosis.

Purpose: To evaluate the serum levels of the soluble form of the CD30 molecule (sCD30) in patients with Hodgkin's disease (HD) to establish whether there is a correlation with clinical features at presentation and prognosis.

Patients And Methods: The sCD30 serum levels of 117 patients were measured at diagnosis with a commercial sandwich enzyme-linked immunoadsorbent assay (ELISA) test kit, and in 78 of these patients the sCD30 levels were also recorded during the follow-up period.

Results: sCD30 levels at diagnosis were increased (> 20 U/mL) in a high proportion of patients (87.

IL-8 mRNA expression and IL-8 production by acute myeloid leukemia cells.

Purified leukemic cells from 30 acute myeloid leukemia (AML) cases at diagnosis were investigated for the presence of interleukin 8 (IL-8) mRNA by Northern blot analysis. IL-8 specific transcripts were detected in uncultured blasts in 14/30 cases, 10/14 from patients with M4-M5 and 4/14 from cases with M0-M3 morphology. The transcript expression was associated with the detection of IL-8 molecule in blast cells by immunostaining performed on cytospin preparations.

ICAM-1 tissue overexpression associated with increased serum levels of its soluble form in Hodgkin's disease.

We investigated ICAM-1/CD54 tissue immunoreactivity and serum levels of its soluble form (sICAM-1) in patients with Hodgkin's disease (HD) at diagnosis. ICAM-1 was strongly expressed in involved tissues, and sICAM-1 serum levels were higher in HD (79 patients) than in controls (P < 0.01), and in patients with more advanced or more active disease (stages III + IV vI + II: P = 0.

Splenectomy for patients with myelofibrosis with myeloid metaplasia: pretreatment variables and outcome prediction.

Since according to the early studies, the outcome after splenectomy in the individual patient with myelofibrosis with myeloid metaplasia (MMM) is unpredictable, we assessed retrospectively the pre-intervention characteristics that best predicted adverse events, hematological consequences, and survival in 71 splenectomized MMM patients. The findings indicate that the operative risk of splenectomy for both mortality (8.4%) and morbidity (39.

Soluble interleukin-2 receptor in hairy-cell leukemia: a reliable marker of disease.

The CD25 molecule, which corresponds to the p55 alpha chain of the interleukin-2 receptor, is strongly expressed by neoplastic cells in hairy-cell leukemia and is released in large amounts in the soluble form which is detectable in serum. In order to assess the reliability of the soluble interleukin-2 receptor as a disease marker in the management of patients with hairy-cell leukemia, we investigated serum levels in 35 untreated patients and in 2 patients with the hairy-cell leukemia variant. In 21 of 35 patients soluble receptor levels were also monitored during and after recombinant interferon-alpha therapy.

Mechanisms of platelet activation by cultured human cancer cells and cells freshly isolated from tumor tissues.

We studied the effects on platelet function of cells isolated from freshly dissociated human tumor tissues (11 breast carcinomas, 9 colon carcinomas and 1 lymph node metastasis from melanoma) obtained at surgery as compared with cultured human tumor cells: namely, human melanoma 1402 cell line derived from a primary tumor and two lines derived from lymph node metastases (ME 7110/2 and Me 665/1) as well as a human hepatoma cell line (Hep G2). The three melanoma cell lines activated platelets by producing ADP, as evidenced by the inhibitory effect of apyrase and by the direct measurement of the agonist in the supernatants of tumor cell suspensions; this production was much greater by the cells derived from metastases than by the cells derived from the primary tumor. On the other hand, aggregation induced by Hep G2 hepatoma cells was unaffected by apyrase and was inhibited by hirudin or concanavalin A, suggesting that the cells aggregate platelets by producing thrombin, probably through tissue factor activity of the cells themselves.

Nicotine alters fibronectin and factor VIII/vWF in human vascular endothelial cells.

Primary cultured human endothelial cells derived from umbilical cord vein were exposed during the growth of the culture to medium containing nicotine at various concentrations (0.5-200 micrograms/ml). Patterns of cellular fibronectin and factor VIII/vWF were compared to control by immunofluorescence technique.

Role of tumor proteinases in tumor cell-induced platelet aggregation.

In a previous work we found a correlation between in vivo metastatic potential of cancer cells and their platelet aggregating activity in sublines of the mFS6 murine fibrosarcoma. In the present study the effects of different proteinase inhibitors on platelet aggregation induced by these cells were investigated. When the platelets were incubated with the inhibitors, only those effective against cysteine proteinases strongly reduced platelet aggregation by cancer cells; serine protease inhibitors, including hirudin, had no effect on platelet response.

Extracellular matrices produced in the presence of dexamethasone: a natural "growth agent" for human cultured endothelium.

Cultured endothelium synthesizes an extracellular matrix that resembles the basement membrane of the vessels. We studied the aspect of extracellular matrices produced in presence or absence of dexamethasone by immunofluorescent technique for fibronectin; the glycoprotein is more abundant in matrices produced in the presence of dexamethasone than controls and forms a very dense meshwork. When endothelial cells resuspended in medium without FCS were seeded on these preformed matrices they adhered and replicated.

The effect of ticlopidine on human endothelial cells in culture.

The effect of ticlopidine at various concentrations (150, 30, 6 microM), has been studied on cultured endothelial cells derived from human umbilical cord vein. Ticlopidine affects the initial attachment of endothelial cells to artificial substrata and has an inhibitory effect on endothelial cell growth rate which correlates to the concentration of the chemical in the culture medium. These effects are related to a marked reduction of intra- and extracellular fibronectin as evidentiated by immunofluorescence.