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Biomedical subjects

G Leone

Publications and source records attributed to G Leone.

At least 199 records · Page 11Linked to original sources
PubMed1997

Evaluation of a new protocol for peripheral blood stem cell collection with the Fresenius AS 104 cell separator.

In this report we analyzed sixty leukapheresis procedures on 35 patients with a new protocol for the Fresenius AS 104. Yields and efficiencies for MNC, CD 34+ cells, and CFU-GM indicate that the new protocol is able to collect large quantities of hemopoietic progenitors. Procedures were performed processing 8.69 +/- 2.8 liters of whole blood per apheresis and modifying 3 parameters: spillover-volume 7 ml, buffy-coat volume 11.5 ml, centrifuge speed 1,500 rpm; blood flow rate was 50 ml/min and the anticoagulant ratio was 1:12. No side effects were observed during apheresis procedures except for transient paresthesia episodes promptly resolved with the administration of calcium gluconate. Yields show a high capacity of the new program to collect on average MNC 17.28 +/- 10.85 x 10(9), CD 34+ 471 +/- 553.5 x 10(6) and CFU-GM 1278.7 +/- 1346.3 x 10(4) per procedure. Separator collection efficiency on average was 49.91 +/- 23.28% for MNC, 55.1 +/- 35.66% for CFU-GM, and 62.97 +/- 23.09% for CD 34+ cells. Particularly interesting are results for MNC yields and CD 34+ efficiency; these results make the new program advantageous or similar to the most progressive blood cell separators and capable to collect a sufficient number of progenitor cells for a graft with a mean of 1.80 +/- 0.98 procedures per patient.

Adolescent↗
PubMed1997

Comparative analysis of prognostic indicators of aspergillosis in haematological malignancies and HIV infection.

The objective of this study was to identify the prognostic factors influencing the outcome of aspergillosis in two models of immunodeficiency, namely haematological malignancies and HIV infection. The study is based on a 5 year prospective logistic regression analysis of risk factors, clinical features, radiological findings and therapy affecting the prognosis of aspergillosis in 43 patients, i.e. 27 haematological neoplastic patients (group A) and 16 HIV infected patients (group B). Univariate analysis indicated that neutropenia (P = 0.02), haemoptysis (P = 0.03) and concomitant AIDS (P = 0.02), negatively influenced the prognosis of aspergillosis. Comparing the two groups of patients, significant differences emerged in the prognostic indicators. In particular respiratory failure (P = 0.02) and radiological bilateral involvement of the lungs were associated with a poor prognosis in group A (P = 0.04) and low (2100/mm3) T CD4+ cell count in group B (P = 0.02). At variance, a better prognosis was documented in patients treated with sequential therapy (amphotericin B and itraconazole) only within the group of haematological patients (P = 0.003). On multivariate analysis sequential therapy (P = 0.01) and AIDS (P = 0.03) were independent prognostic indicators of aspergillosis. In conclusion, our prospective study indicates that aspergillosis, although an uncommon event in patients with HIV infection, has a more severe prognosis in comparison to haematological patients. Future prospective clinical trials are necessary to confirm the real importance of the sequential therapy, with amphotericin B and itraconazole, in patients with aspergillosis.

Adult↗
PubMed1997

Direct detection of potato leafroll virus in potato tubers by immunocapture and the isothermal nucleic acid amplification method NASBA.

NASBA, an isothermal amplification method for nucleic acids, was applied to the detection of RNA of potato leafroll virus (PLRV) in a single enzymatic reaction at 41 degrees C. A set of primers was selected from the coat protein open reading frame sequence of PLRV to allow amplification of viral RNA. The NASBA reaction products were visualized after electrophoresis by ethidium bromide or acridine orange staining. The specificity of the amplification products was validated by Northern blot analysis with a PLRV-specific 32P-labelled oligonucleotide probe. The procedure was coupled to immunocapture of PLRV virions from tuber extracts by immobilized antibodies in microtubes. It was possible to discriminate readily by this method between uninfected and primarily PLRV-infected potato tubers. NASBA is suitable for the direct detection of PLRV in potato tubers from primarily infected plants, offering the potential to considerably simplify the inspection of seed-potatoes for virus infection.

Animals↗
PubMed1997

High-dose carboplatin, etoposide and melphalan (CEM) with peripheral blood progenitor cell support as late intensification for high-risk cancer: non-haematological, haematological toxicities and role of growth factor administration.

The present report describes the non-haematological toxicity and the influence of growth factor administration on haematological toxicity and haematopoietic recovery observed after high-dose carboplatin (1200 mg m(-2)), etoposide (900 mg m(-2)) and melphalan (100 mg m(-2)) (CEM) followed by peripheral blood progenitor cell transplantation (PBPCT) in 40 patients with high-risk cancer during their first-line treatment. PBPCs were collected during the previous outpatient induction chemotherapy programme by leukaphereses. CEM administration with PBPCT was associated with low non-haematological toxicity and the only significant toxicity consisted of a reversible grade III/IV increase in liver enzymes in 32% of the patients. Haematopoietic recovery was very fast in all patients and the administration of granulocyte colony-stimulating factor (G-CSF) plus erythropoietin (EPO) or granulocyte-macrophage colony-stimulating factor (GM-CSF) plus EPO after PBPCT significantly reduced haematological toxicity, abrogated antibiotic administration during neutropenia and significantly reduced hospital stay and patient's hospital charge compared with patients treated with PBPCT only. None of the patients died early of CEM plus PBPCT-related complications. Low non-haematological toxicity and accelerated haematopoietic recovery renders CEM with PBPC/growth factor support an acceptable therapeutic approach in an adjuvant or neoadjuvant setting.

Adult↗
PubMed1997

Inhibition of lymphocyte blastogenic response in healthy donors treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF): possible role of lactoferrin and interleukin-1 receptor antagonist.

The effects of rhG-CSF on lymphocyte blastogenesis were evaluated in six healthy donors, submitted to progenitor cell mobilization for allogeneic transplantation. Neutrophil, monocyte and lymphocyte count increased 6.7-fold, 5.3-fold and 2.0-fold on day +4 of rhG-CSF as compared with baseline. The DNA stimulation index (DNA SI) of 72 h phytohemagglutinin (PHA)-treated cultures decreased from 20% (15-35.5) prior to rhG-CSF to 6.7% (1.5-11.9; P = 0.0026), 8% (4-12; P = 0.0091) and 15% (9-22; P = 0.0091) on days +2, +4 and +6; similarly, reactivity to concanavalin A decreased from 18% (12-20) to 1.8% (0.5-7; P < 0.01), 3% (2-8; P < 0.01) and 5% (2-11; P = 0.009). No changes of lymphocyte response to pokeweed mitogen were observed. DNA SI of PHA-treated cultures inversely correlated with neutrophil and monocyte count. IL-1 receptor antagonist (IL-1ra) and lactoferrin (Lf) plasma levels sharply increased and correlated with neutrophil and monocyte count. IL-10 increased five-fold on day +2, returned to pretreatment values thereafter and did not show any correlation with DNA SI, suggesting that it was not responsible for the observed phenomena. Interestingly, DNA SI of PHA-treated cultures inversely correlated with IL-1ra and Lf levels. CD3+ and CD19+ lymphocyte activation status, ie CD23, CD25, CD30 and HLA-DR coexpression, was not affected by rhG-CSF administration. Pharmacological doses of rhG-CSF in healthy donors inhibit lymphocyte blastogenesis via an increased production and/or release of immunoregulatory soluble mediators, ie IL-1ra and Lf, by primed neutrophils and monocytes.

Adult↗
PubMed1997

Generation of multinuclear tartrate-resistant acid phosphatase positive osteoclasts in liquid culture of purified human peripheral blood CD34+ progenitors.

Circulating CD34+ cells were isolated from leukapheresis products collected from patients with ovarian cancer. CD34 contaminating cells, identified immediately after immunoselection, ranged from 5% to 25% in five different experiments and were predominantly CD3+ T-lymphocytes (range 2-12%), CD3+/CD16+/CD56+ natural killer cells (range 2-11%) and rare mature CD15+/ CD11b+ granulocytes (range 1-2%). CD34+ cells were cultured in liquid medium in the presence of interleukin-3, granulocyte-macrophage colony stimulating factor. stem cell factor, granulocyte colony stimulating factor and a powerful proliferation with prevalent differentiation along the granulocytic/monocytic lineage was obtained. After 10 d of culture a small but consistent number of early multinucleated osteoclasts were identified with a frequency of one cell per 700 granulocytic/monocytic cells, as revealed by cytologic examination. This observation was confirmed by staining for tartrate-resistant acid phosphatase activity which revealed red multinucleated elements with a frequency comparable to that reported above. Conversely, no osteoclasts were observed in those cultures in which macrophage overgrowth was obtained by culturing CD34+ cells until day 35. These observations suggest that circulating progenitors have a multilineage potential in vitro and contribute to the clarification of osteoclast development in humans: additionally, they provide the basis for the future development of optimized osteoclast culture techniques in liquid medium and the basic culture system, to test the distinct activity of 1,25(OH)2D3. parathyroid hormone interleukin-11 and of other cytokines on osteoclast development in humans.

Acid Phosphatase↗
PubMed1997

Purified unfractionated G-CSF/chemotherapy mobilized CD34+ peripheral blood progenitors and not bone marrow CD34+ progenitors undergo selective erythroid differentiation in liquid culture in the presence of erythropoietin and stem cell factor.

A combination of erythropoietin (EPO) plus stem cell factor (SCF) drove purified unfractionated granulocyte colony stimulating factor (G-CSF)/chemotherapy mobilized peripheral blood CD34+ cells to selective erythroid differentiation in liquid culture with an average 28-fold increase in the total cell number after 21 d. From day 6 of culture cytologic and cytofluorimetric characterization revealed that cultured cells belonged to the erythroid lineage with a gradual wave of maturation along the erythroid pathway to terminal cells. A similar pattern of erythroid differentiation was observed when the same peripheral blood CD34+ cells were culture with EPO plus SCF in serum-free medium. This cytokine combination produced selective erythroid differentiation with the complete exhaustion of the clonogenic potential on day 21. In parallel experiments the same circulating CD34+ cells underwent granulocytic/ monocytic differentiation in liquid culture in response to granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-3 (IL-3) and SCF, demonstrating that these CD34+ progenitors had intact pluripotent differentiating potential. Conversely, bone marrow CD34+ cells isolated from bone marrow allografts were unable to selectively differentiate along the erythroid pathway when they were exposed to EPO plus SCF combination. However, these cells maintained a greater number of colony forming cells on day 21 of culture compared to mobilized peripheral blood CD34+ cells. This model is a simple and reliable way to obtain selective erythroid differentiation of peripheral blood G-CSF/ chemotherapy mobilized CD34+ progenitor cells in liquid culture. The absence of cytokines such as GM-CSF and IL-3 in the culture medium permits studies on in vitro erythropoiesis without disturbance of prevalent myelopoiesis.

Antigens, CD34↗
PubMed1997

Autologous stem cell transplantation: evaluation of erythropoietic reconstitution by highly fluorescent reticulocyte counts, erythropoietin, soluble transferrin receptors, ferritin, TIBC and iron dosages.

The plasma concentrations of erythropoietin (Ep), soluble transferrin receptors (sTfRs), iron, total iron binding capacity (TIBC) and ferritin were monitored in five leukaemia patients undergoing autologous bone marrow stem cell transplantation (BMSCT) and in 10 lymphoma and 21 ovarian cancer patients undergoing autologous peripheral blood SCT (PBSCT); 9/21 ovarian cancer patients received recombinant human G-CSF and Ep and six recombinant human GM-CSF and Ep following SCT. All parameters were evaluated in relation to the kinetics of erythroid reconstitution as evaluated by haemoglobin (Hb) and reticulocyte levels [including the fraction of immature reticulocytes, also called highly fluorescent reticulocytes (HFR)]. Leukaemia patients undergoing BMSCT showed only a delayed (occurring at days 35-50 after SCT) and partial RBC, neutrophil and platelet recovery, whereas all patients undergoing PBSCT exhibited a rapid (occurring at days 10-15 after SCT) and sustained haemopoietic recovery. The various levels of erythroid rescue observed among these patients markedly influenced the kinetics of the different parameters investigated: (i) in leukaemia BMSCT patients sTfRs declined following SCT and remained at low levels thereafter, whereas Ep, iron. TIBC and ferritin showed a progressive and significant increase; (ii) in the different groups of patients undergoing PBSCT: (a) sTfR levels first declined following SCT and then returned to pre-therapy values at days 12-16, this response preceded erythropoietic recovery; (b) Ep, total iron, TIBC and ferritin showed an initial increase in the first days following SCT and then returned to pre-therapy values. Altogether, these observations indicate that: (i) both sTfR levels and reticulocyte counts are predictive parameters of erythropoietic recovery; (ii) coordinated changes of biochemical parameters underlying iron metabolism (iron, TIBC and ferritin) accompany erythroid rescue following SCT.

Adolescent↗
PubMed1997

Evaluation of two different protocols for peripheral blood stem cell collection with the Fresenius AS 104 blood cell separator.

OBJECTIVES: Reconstitution of hematopoiesis by means of peripheral blood stem cells is a valid alternative to autologous bone marrow transplantation. The aim of this investigation was to increase the efficiency of collection of circulating blood progenitor cells and to obtain a purer product for transplant. METHODS: We carried out leukapheresis procedures with the Fresenius AS 104 blood cell separator, using two different protocols, the previously used PBSC-LYM and a new mononuclear cell collection program. RESULTS: Both programs were highly effective in collecting mononuclear cells (MNC) and CD34+ cells. Some differences were found, especially regarding MNC yield and efficiencies. There are remarkable differences in the efficiency of collection of CD34+ cells (62.38% with the new program as opposed to 31.69% with the older one). Linear regression analysis showed a negative correlation between blood volume processed and MNC efficiency only for the PBSC-LYM program. Differences were also observed in the degree of inverse correlation existing in both programs between patients' white blood cell precount and MNC collection efficiency. The inverse correlation was stronger for the PBSC-LYM program. Seven patients with solid tumors and hematologic malignancies received high dose chemotherapy and were subsequently transplanted with peripheral blood stem cells collected using the new protocol. All patients obtained a complete and stable engraftment with the reinfusion product collected with one or two leukapheresis procedures. CONCLUSIONS: High efficiencies and yields were observed in the new protocol for MNC and CD34+ cells. These were able to effect rapid and complete bone marrow recovery after myeloablative chemotherapy.

Adolescent↗
PubMed1997

Spontaneous erythroid colony formation as the clue to an underlying myeloproliferative disorder in patients with Budd-Chiari syndrome or portal vein thrombosis.

Budd-Chiari syndrome is a severe disease characterized by occlusion of large hepatic veins leading to death if untreated. Using the classical criteria for the diagnosis of polycythemia vera (PV), essential thrombocythemia (ET), and idiopathic myelofibrosis (IMF), overt PV was the underlying cause in about 10% of the cases and ET or IMF in only a very few. Using spontaneous endogenous erythroid colony (EEC) formation in vitro and/or bone marrow biopsies, a primary myeloproliferative disorder (PMD) was present in 78% of the patients with apparently idiopathic Budd-Chiari syndrome and in about half of the patients with portal, splenic, and/or mesenteric vein thrombosis. The diagnoses in 40 reported cases with hepatic vein thrombosis and spontaneous EEC were overt PV in 25 and latent unclassified PMD in 15 patients. The diagnoses of 40 reported cases with splanchnic vein thrombosis and spontaneous EEC were overt PV in 12, ET in 2, IMF in 2, and latent unclassified PMD with the presence of EEC in 24 patients. Thrombocytosis as a manifestation of myeloproliferative disease was recorded in 34 of 80 (42.5%) patients with spontaneous EEC and Budd-Chiari syndrome or portal vein thrombosis. Thrombocythemia was present in 15 of 41 patients with a proven and in 19 of 39 patients with a latent myeloproliferative disorder. Patients with hepatic vein or splanchnic vein thrombosis associated with a PMD are predominantly females younger than 45. It is concluded that both spontaneous EEC and histopathology from bone marrow biopsy provide specific information as sensitive clues to the diagnosis of all variants of overt and latent myeloproliferative disorders. The association of hepatic and splanchnic vein thrombosis and PMD is not fully understood. Therapeutic options of Budd-Chiari syndrome include anticoagulation with heparin, fibrinolysis followed by oral anticoagulation, and appropriate treatment of the underlying PMD. In case of failure, invasive options include local procedures such as angioplasty or stenting, venous decompression by portal-systemic shunts, or liver transplantation.

Biomarkers↗
PubMed1997

The role of bronchoalveolar lavage in the microbiological diagnosis of pneumonia in patients with haematological malignancies.

In the aetiological diagnosis of pulmonary infections in patients affected by haematological malignancies we evaluated the utility of bronchoalveolar lavage (BAL). One hundred and twenty-seven BAL were performed in 119 patients. In our series, we identified the agent of pneumonia in 53.5% of episodes with the best results in aspergillosis, very common in these patients. The previous empirical anti-infective treatment was modified in 14 episodes (11%). The procedure was generally well tolerated and only one patient bled. We maintain that BAL is a useful diagnostic tool for detecting the agents of pulmonary infections in patients with haematological malignancies, especially when the routine microbiological procedures fail, and it also represents a good alternative to more invasive procedures.

Adolescent↗
PubMed1997

Growth factor administration following autologous peripheral blood progenitor cell transplantation.

Hematopoietic growth factor (HGF) administration following autologous peripheral blood progenitor cell transplantation (APBPCT) is a current approach for shortening the duration of high-dose chemotherapy-induced transient peripheral pancytopenia. Several published clinical experiences and a retrospective study reported here show that recombinant human granulocyte colony stimulating factor (rhG-CSF) or recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) administration potentiates polymorphonuclear leukocyte (PMN) and white blood cell (WBC) recovery with some clinical benefits mainly related to the reduction of infectious complications during the shortened period of neutropenia. However, this therapeutic strategy does not produce any enhancement of platelet (PLT) recovery or potentiation of red cell production. Conversely, a recent phase I/II study carried out in our institution showed that the combined administration of rhG-CSF and recombinant human erythropoietin (rhEPO) is able to potentiate trilineage hematopoietic recovery with a reduction of PLT transfusions and to considerably simplify the clinical management of patients as compared to patients treated with APBPCT alone. The post-APBPCT administration of rhEPO with rhGM-CSF decreased the number of days with WBC < 1 x 10(9)/L but failed to produce any appreciable effect on PLT recovery. Both combined treatments significantly reduced the patients' hospital stay and allowed the abrogation of systemic antibiotic administration following APBPCT. A further group of patients were treated with the combined administration of rhEPO, rhG-CSF and rhGM-CSF; they did not show a faster hematopoietic recovery than rhG-CSF plus EPO treated patients and a consistent hyperthermia was observed in most patients as a prominent side effect. Future prospective randomized studies will clarify the efficacy of HGF administration following APBPCT. Moreover, further improvements in the hematopoietic support of transplanted patients may be obtained when stem cell factor, flt3/flk2 tyrosine kinase ligands or megakaryocyte growth and development factor will become clinically available.

Erythropoietin↗
PubMed1997

RhG-CSF-mobilized CD34+ peripheral blood progenitors are myeloperoxidase-negative and noncycling irrespective of CD33 or CD13 coexpression.

Cycling status, myeloperoxidase expression, informative surface markers, and proliferative potential of peripheral blood hemopoietic progenitors (PBHP) were evaluated by flow cytometry in 10 patients affected by resistant lymphoma, and submitted to stem cell mobilization with combination chemotherapy (MiCMA) followed by recombinant human granulocyte colony-stimulating factor (rhG-CSF, 5 micrograms/kg/day). CD34+ PBHP coexpressed myeloid-associated and activation antigens, i.e., CD33 (96%, range 85-99), CD13 (99.5%, range 99.4-99.8), HLA-DR (99%, range 96.5-99.8), and CD38 (98%, range 90-100), lacked intracytoplasmic myeloperoxidase (MPO, < 3%), and resided in the Gzero/G1 phase of the cell cycle (96.5%, range 81-99.5, compared with 70%, range 49-78 bone marrow HP; p = 0.0007), independently of surface membrane phenotype; S-phase percentages of sorted CD34+ CD33(+)/-, CD34+CD38(+)/-, CD34+HLA-DR(+)/-, CD34+CD45RA(+)/-, CD34+CD45RO(+)/-, and CD34+CD41a(+)/- subpopulations were always negligible. In colony assays, 5-week-old long-term cultures seeded with CD34+CD33- cells yielded as many colonies as did CD34+CD33+ cells. In conclusion, rhG-CSF-mobilized CD34+ PBHPs contain noncycling, highly immature progenitors in which the expression of myeloid-associated antigens, i.e., CD33 or CD13, might not be indicative of myeloid commitment.

Antigens, CD↗