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V Rizzoli

Publications and source records attributed to V Rizzoli.

At least 55 records · Page 3Linked to original sources
PubMed1995

Arachidonic acid induces c-jun gene expression in stromal cells stimulated by interleukin-1 and tumor necrosis factor-alpha: evidence for a tyrosine-kinase-dependent process.

We have previously shown that granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression induced by interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) in the murine stromal cell line +/+.1-LDA 11 involves activation of phospholipase A2 (PLA2). Furthermore, induction of GM-CSF gene expression due to release of arachidonic acid as a result of PLA2 activation was mediated by the transcriptional factor c-jun. In the present study, we have investigated the potential mechanism involved in the induction of c-jun gene expression by arachidonic acid. Arachidonic acid induced transcription of c-jun mRNA. Downregulation of protein kinase C (PKC) by chronic exposure of stromal cells to the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA; 400 nmol/L) did not effect c-jun expression induced by arachidonate. Moreover, pretreatment of cells with the PKC inhibitor, calphostin C (1 mumol/L), caused a marked decrease of c-jun expression induced by TPA, but had no influence on c-jun expression induced by arachidonate. To explore the hypothesis that a tyrosine kinase signalling pathway, independent of PKC activation, was involved in arachidonate-induced c-jun expression, stromal cells were pretreated with the protein tyrosine kinase inhibitor, genistein, before challenge with arachidonic acid. Arachidonate 50 mumol/L)-induced c-jun expression was inhibited, in a dose- and time-dependent manner, by genistein. Genistein similarly inhibited c-jun expression in stromal cells exposed to IL-1 (500 U/mL) plus TNF-alpha (500 U/mL). The potential role of a tyrosine kinase pathway in arachidonate-mediated c-jun expression was further investigated by assaying the tyrosine kinase activity of cells challenged with arachidonic acid, IL-1, and TNF-alpha. Exposure of stromal cells to arachidonic acid induced a 2.1-fold increase in intracellular tyrosine kinase activity determined by phosphorylation of the synthetic peptide, raytide, in the presence of [gamma-32P]-ATP. Similarly, IL-1 and TNF-alpha induced 1.7- and 2.4-fold increases in tyrosine protein kinase activity, respectively. The effect of arachidonic acid on tyrosine kinase activity was inhibited by genistein and was enhanced by sodium vanadate. The increase of protein tyrosine kinase activity detected in arachidonate-stimulated cells was associated, in a dose- and time-dependent fashion, with tyrosine phosphorylation of 240-, 40-, and 29-kD substrates. These results are consistent with the hypothesis that a tyrosine phosphorylation process is triggered by arachidonate as an early event in the signalling pathway that leads to increased expression of c-jun.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

Density separation of umbilical cord blood and recovery of hemopoietic progenitor cells: implications for cord blood banking.

Umbilical cord blood (CB) has been evaluated as a potential source of hematopoietic stem cells suitable for clinical use in the transplantation setting. Previous reports have documented a significant loss of progenitor cells by any manipulation other than cryopreservation. We have evaluated the feasibility of fractionating and cryopreserving CB samples with minimal loss of progenitor cells. We have compared various separation procedures based on different density gradients in the attempt to obtain the highest depletion of red blood cells (RBC) while maintaining the highest recovery of progenitor cells. We compared three different densities of Percoll (1.069 g/ml, 1.077 g/ml, 1.084 g/ml), sedimentation over poligeline (Emagel ) and sedimentation over poligeline followed by separation over Ficoll/Hypaque (F/H). Separated samples (n = 25) were analyzed for recovery of CD34+ cells and progenitor cells (CFU-GEMM, BFU-E, CFU-GM). Separation by sedimentation over poligeline followed by F/H allowed the highest depletion of RBC (hematocrit of the final cellular suspension 0.4 +/- 0.1%) while maintaining high recovery of CD34+ cells (85.3 +/- 5.6%) and total recovery for CFU-GEMM, BFU-E and CFU-GM. After cryopreservation, recovery of clonogenic progenitors was 82% for CFU-GEMM, 94% for BFU-E, 82% for CFU-GM and 90% for colony-forming units (CFUs) after five weeks of long-term culture (LTC). We further evaluated the effect of stem cell factor (SCF) on the in vitro growth of hemopoietic progenitors and on replating efficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗
PubMed1995

Techniques for detection of minimal residual disease.

Analysis of leukemia-specific and leukemia-associated markers following standard or high-dose treatments is crucial in order to evaluate the efficacy of therapeutic strategies. During the last decade, several techniques have been proposed and used for detecting minimal residual disease (MRD). Each approach is characterized by advantages and limitations, mainly related to its sensitivity and specificity. The general limitations of such tests originates from the size of the sample which can be analysed and the heterogeneous distribution of leukemia after treatment. Clinically useful methods for detecting residual leukemia require not only sensitivity but also speed and reproducibility. The rate of false negative tests is low with polymerase chain reaction as well as flow cytometric analysis. Usually, patients without persistent cells carrying leukemia-associated markers have a lower risk of relapse. However, the detection of a persistent marker at one time point in complete remission cannot be considered a reliable indicator of MRD, whereas increase of positive signals or reappearance of leukemic markers usually precedes relapse. It is likely that one single approach will not allow the monitoring of the majority of patients and that a combination of techniques will be needed. Definitive results will be obtained only through prospective studies in patients receiving standardised therapy. Studies in which therapeutic strategies are designed according to the results provided by techniques for detecting MRD will be necessary to assess the relevance of their contribution to the treatment of leukemia.

Bone Marrow↗
PubMed1995

[Laparoscopic splenectomy: comments on the surgical technic].

The authors describe the technique applied in their first case of laparoscopic splenectomy, in a patient with idiopathic thrombocytopenic purpura. Different technical approaches adopted by other surgeons are referred and discussed. The laparoscopic approach to splenectomy seems safe and allows the patients to re return to normal activity sooner than the "open" technique. Laparoscopy should be considered in patients who require splenectomy for benign disease.

Adult↗
PubMed1995

Natural killer cell regeneration after transplantation with mafosfamide purged autologous bone marrow.

Autologous bone marrow transplantation (ABMT) is used increasingly for the treatment of acute leukemias, lymphomas and solid tumors. Since ABMT is burdened by high risk of relapse, mafosfamide or 4-hydroperoxycyclophosphamide chemical marrow purging is employed. Mafosfamide acts by exerting a potent cytotoxic effect and by promoting apoptosis of leukemic cells. A third proposed mechanism of action involves an effect on immune regeneration in vivo. It was the aim of this study to investigate natural killer (NK) cell regeneration in a group of patients undergoing mafosfamide-purged ABMT. Fifteen patients (8 acute myelogenous leukemia, AML; 4 acute lymphoblastic leukemia, ALL; 3 non-Hodgkin's lymphoma, NHL) were treated with high-dose chemotherapy followed by transplantation with marrow purged with mafosfamide. Prior to ABMT and at different intervals thereafter, NK cell number and function were studied by evaluating the percentage of circulating CD16 positive cells and cytotoxic activity against the leukemic cell line, K562. In comparison to pre-ABMT values, AML patients showed a significant increase in cytotoxic activity, expressed as percentage of chromium release (42.5 +/- 3 vs 32.5 +/- 6, P < or = 0.025 at 4 months) which still persisted at 12 months post-ABMT (54 +/- 6, P < or = 0.05). The behavior of NK functional activity was paralleled by an increase of the percentage of CD16-positive cells (8.4 +/- 2.2 vs 5 +/- 1.3, P < or = 0.05 at 4 months; 12.8 +/- 2.4, P < or = 0.005 at 12 months post-ABMT). Similar significant and long-lasting increments in NK cells were also found in NHL patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Stem cell purging: an intriguing dilemma.

Autologous stem cell transplantation (ASCT) is a therapeutic approach that permits the administration of high-dose chemoradiotherapy followed by the infusion of the patient's own hemotopoietic cells, previously collected during remission and cryopreserved [1-4]. The long-term outcome of ASCT is mainly affected by relapse of the underlying disease that represents the major cause of failure of ASCT. The contribution of reinfused tumor cells to relapse is suggested by several clinical studies and has been recently demonstrated by autografting genetically marked cells. In this minireview, advantages and limitations of currently available purging techniques will be analyzed. In addition, the potential clinical implications of new technological approaches for purging will be discussed.

Bone Marrow Purging↗
PubMed1994

Identification of Philadelphia-negative granulocyte-macrophage colony-forming units generated by stroma-adherent cells from chronic myelogenous leukemia patients.

Chronic myelogenous leukemia (CML) is a clonal disorder of the hematopoietic stem cell characterized by the coexistence of Philadelphia-negative (Ph-) with Ph+ progenitors. CML progenitor cells have been shown to be defective in adherence to marrow stroma. The present study investigated at the cytogenetic level marrow-derived CML clonogenic cells generated from the stroma-adherent cell fraction. On direct cytogenetic analysis, the overall mean (+/- SEM) percentage of Ph- metaphases was 3% +/- 1%. Mononuclear marrow cells from CML patients (n = 18) were incubated with mafosfamide (100 micrograms/mL) or control medium, seeded onto marrow stromal layers and allowed to adhere (2 hours, 37 degrees C). After a short-term (3-day) liquid culture, the cells were harvested, incorporated in methyl-cellulose, and individual colonies were analyzed by single colony karyotyping. The mean (+/- SEM) percentage of Ph- colonies generated from the stroma-adherent fraction was 35% +/- 6%. As compared with marrow colony-forming unit granulocyte-macrophage plated before any manipulation, the mean (+/- SEM) percentage of Ph- clones was significantly increased by stroma adherence (35% +/- 6% v 15% +/- 4%, P < or = .005) and mafosfamide (100 micrograms/mL) incubation of marrow cells before stroma adherence (58% +/- 9% v 35% +/- 6%, P < or = .005). An additive effect was observed by combining mafosfamide treatment and stroma adherence. Single-colony transfer experiments showed that 50% +/- 4% stroma-adherent and 70% +/- 4% stroma-adherent mafosfamide-treated progenitors gave rise to secondary colonies. To further characterize the stroma-adherent fraction, experiments were performed in which CD34+ marrow cells were used. The mean (+/- SEM) output of progenitors generated by 10,000 CD34+, stroma-adherent cells was 888 +/- 188 and 570 +/- 258 for untreated and mafosfamide-treated cells, respectively. Individual colonies were analyzed by single-colony karyotyping and fluorescent in situ hybridization using a biotinylated cosmid DNA probe that hybridize to abl oncogene. The CD34+, stroma-adherent fraction contained 38% +/- 14% (untreated) and 56% +/- 18% (mafosfamide-treated) (P < or = .025) Ph- progenitors. In conclusion, the present data show the possibility to select Ph- clones that (1) have a maintained capability of stroma adherence, (2) are mafosfamide resistant, (3) are derived from the CD34+ fraction, and (4) have high-replating potential.

Adult↗
PubMed1994

Impact of interferon at induction chemotherapy and maintenance treatment for multiple myeloma. Preliminary results of a multicenter study by the Italian non-Hodgkin's Lymphoma Cooperative Study Group (NHLCSG).

In 1990 the Italian Non-Hodgkin's Lymphoma Cooperative Study Group (NHLSG) started a multicenter study on the role of interferon (IFN) in multiple myeloma (MM). The schedule of treatment was based on the assumption that melphalan plus prednisone (MP) would be better for good-prognosis patients, whereas poor-prognosis patients would benefit from polychemotherapy. Accordingly, IFN was included randomly for the induction treatment of good-prognosis patients and randomly as maintenance of the response achieved in both groups. Up to now 78 patients of the 124 enrolled have completed the induction treatment and are evaluable for response and response duration. The overall response rate was 59%. Sixty-two percent of good-prognosis patients obtained objective response, 9/14 (64%) with MP and 9/15 (60%) with MP+IFN. Up to now, with a median follow-up of 9 months from the evaluation of response, no difference has been recorded between the maintenance and no maintenance groups on relapse rate, neither in good- nor in poor-prognosis patients.

Aged↗
PubMed1994

Autologous transplant for chronic myelogenous leukemia using marrow treated ex vivo with mafosfamide.

Ten adult patients with Ph-positive chronic myelogenous leukemia (CML) received autologous transplantation using marrow treated ex vivo with mafosfamide. At transplant, 7 patients were in chronic phase (5 in first, 2 in second) and 3 in accelerated phase. The median time to achieve 500 x 10(6)/l neutrophils was 32 days (range 17-72 days). A platelet count of 20 x 10(9)/l was achieved at a median of 40 days (range 24-151 days). After transplant, cytogenetic analysis revealed 100% Ph-negative marrow metaphases in 6 of 9 analyzable patients with a median duration of Ph-negative hematopoiesis of 6.5 months. After a median follow-up of 16 months (range 3-31 months), five patients evolved into blast crisis, two died of non-hematological causes, one is Ph-negative in chronic phase at +4 and one is in chronic phase, but Ph-positive, at +22. In conclusion, this pilot study demonstrates that: (1) engraftment can occur from Ph-negative stem cells selected by mafosfamide, (2) mafosfamide purging may induce a transient period of Ph-negative hematopoiesis, and (3) modifications of the purging procedure and post-transplant manipulations of the immune-hematopoietic system are required to prolong cytogenetic remission.

Adult↗
PubMed1993

Effect of recombinant human stem cell factor on mafosfamide-treated bone marrow clonogenic cells.

The availability of early-acting cytokines could allow the establishment of new approaches to chemical marrow purging. It was the aim of the present study to investigate the capability of recombinant human stem cell factor (SCF) in combination with other growth factors to support the in vitro growth of mafosfamide-treated progenitor cells such as mixed colony forming units (CFU-GEMM), erythroid burst forming units (BFU-E) and granulocyte-macrophage CFU (CFU-GM). When marrow cells were incubated (30 min, 37 degrees C) with increasing doses of mafosfamide (30-120 micrograms/ml) a statistically significant (p < or = .05), dose-dependent suppression of colony growth was observed. Addition of SCF (50 ng/ml) to marrow cultures stimulated with the standard mixture of growth factors (interleukin 3 or IL-3, granulocyte-macrophage colony stimulating factor or GM-CSF, and erythropoietin or Epo) significantly increased the mean (+/- SD) concentration of mafosfamide inducing 95% inhibition of CFU-GM (106 +/- 17 versus 130 +/- 29, p < or = .0005), but not granulocyte/erythroid/macrophage/megakaryocyte CFU (CFU-GEMM) (85 +/- 4 versus 90 +/- 1, p < or = .1) and BFU-E (90 +/- 5 versus 92 +/- 5, p < or = .1). SCF induces a dose-dependent, statistically significant enhancement of colony formation by CD34+, mafosfamide-treated cells. As shown by single colony transfer experiments, mafosfamide-resistant clones promoted by SCF have a significantly higher replating capacity as compared with mafosfamide-resistant clones grown without SCF.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗
PubMed1993

Autologous transplantation for chronic myelogenous leukemia with mafosfamide-treated marrow.

Ten adult patients with Ph-positive chronic myelogenous leukemia (CML) received autologous bone marrow transplantation (ABMT) using marrow treated ex vivo with mafosfamide. At the time of ABMT, six patients were in chronic phase and four in accelerated phase. Seven of ten patients reported herein were selected on the basis of a previous laboratory assessment of the numbers of normal and leukemic stroma-adherent progenitor cells within mafosfamide-treated marrow. Only patients showing > or = 50% Ph-negative stroma-adherent progenitor cells within mafosfamide-treated marrow were considered eligible for autografting. In nine out of ten evaluable patients, the median time to achieve 500 neutrophils/microliters was 32 days (range: 25-72). A platelet count of 2 x 10(4)/microliters was achieved at a median of 40 days (range: 27-97). Six out of nine analyzable patients engrafted Ph-negative. The median duration of the Ph-negative hematopoiesis, confirmed also by Southern blot analysis, was 6.5 months (range: 4-30). A good correlation was evident between the results of the in vitro preharvest screening test and the in vivo occurrence of normal hematopoiesis post-transplant. Two patients who showed 75% and 89% Ph-negative stroma-adherent progenitors engrafted Ph-positive, whereas four out of five evaluable patients who had 100% Ph-negative stroma-adherent progenitors engrafted Ph-negative. After a median follow-up of 16 months (range: 3-31), five patients evolved into blast crisis, three are alive in hematologic and cytogenetic relapse, and one died without evolving into blast crisis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Biological and chemical selection of Ph-negative clones.

Chronic myelogenous leukemia (CML) is a clonal disorder of the hematopoietic stem cell characterized by the co-existence of Philadelphia-negative with Ph-positive progenitors. CML progenitor cells have been shown to be defective in adherence to marrow stroma. The present study investigated at the cytogenetic level marrow-derived CML clonogenic cells generated from the stroma-adherent cell fraction. Mononuclear marrow cells from CML patients (n = 20) were incubated with mafosfamide (100 micrograms/ml) or control medium, seeded onto marrow stromal layers, and allowed to adhere (2 h, 37 degrees C). Following a short-term (3 days) liquid culture, the cells were harvested, incorporated in methylcellulose, and individual colonies were analyzed by single colony karyotyping. On direct cytogenetic analysis, the overall mean (+/- SD) percentage of Ph-negative metaphases was 9 +/- 20%. The mean (+/- SD) percentages of Ph-negative colonies grown from the stroma-adherent and the stroma-adherent mafosfamide-treated fraction were 41 +/- 32% and 62 +/- 40% (p < or = .005), respectively. Single colony transfer experiments revealed that 50 +/- 13% stroma-adherent and 70 +/- 24% stroma-adherent mafosfamide-treated progenitors gave rise to secondary colonies. In conclusion, the present data demonstrate the possibility to select Ph-negative clones that: 1) have a maintained capability of stroma adherence; 2) are mafosfamide resistant; and 3) have high-replating potential.

Cell Adhesion↗
PubMed1993

Fractionation of chronic myelogenous leukemia marrow cells by stroma adherence: implications for marrow purging.

Chronic myelogenous leukemia (CML) progenitor cells have been shown to be defective in their ability to adhere to marrow stroma. It was the aim of the present study to investigate at the cytogenetic level marrow-derived CML clonogenic cells fractionated on the basis of their ability to adhere to preformed, allogeneic, normal marrow-derived stromal layers. Mononuclear marrow cells from CML patients (n = 15) were incubated with mafosfamide (100 micrograms/ml) or control medium, seeded onto marrow stromal layers and allowed to adhere (3 hrs, 37 degrees C). Following a short-term liquid culture, the different cell fractions were harvested and incorporated in methylcellulose cultures. CFU-GM grown from these cultures were analyzed by single colony karyotyping. On direct cytogenetic analysis, the overall mean (+/- SD) percentage of Ph-negative metaphases was 7 +/- 20%. Following stroma adherence and shortterm suspension culture, the mean (+/- SD) percentages of Ph-negative clones were as follows: 33 +/- 25% for adherent CFU-GM, 59 +/- 40% for adherent, mafosfamide-treated CFU-GM, 12 +/- 16% for non-adherent CFU-GM, and 32 +/- 26% for non-adherent-mafosfamide-treated CFU-GM. If only the patients showing a percentage of Ph-negative clones > or = 20% were included in this analysis, the mean (+/- SD) percentages of Ph-negative clones were 47 +/- 19% for adherent CFU-GM, and 81 +/- 21% for adherent-Mafosfamide-treated CFU-GM. In contrast, the majority of pH-positive CFU-GM were detected within the stroma non-adherent cell fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Marrow Cells↗
PubMed1993

Bone marrow transplantation in patients with acute leukemia.

At least three factors may be responsible for leukemic relapse in patients receiving ABMT: (a) minimal residual disease; (b) leukemic cells reinfused with the graft; and (c) the lack of a graft-versus leukemia effect. Techniques for pharmacological marrow decontamination, clinical result obtained with ABMT and the efficacy of ABMT with mafosfamide purged marrow in patients with acute myelogenous leukemia are reviewed.

Adjuvants, Immunologic↗
PubMed1993

Biology and clinical applications of long-term bone marrow cultures.

A number of clonogenic assays for short-term bone marrow culture is now available for the quantitative analysis of the various hematopoietic progenitor cell classes. The short-term assays are not suitable to analyse either stem cell self-renewal or interactions of hematopoietic progenitors with stromal cells, especially those requiring direct cell-to-cell or cell-to-matrix contact. The technique of long-term bone marrow culture (LTBMC) allows a sustained production of myeloid cells when marrow is placed in liquid culture at relatively high cell concentration, with appropriate supplements, temperature and feeding conditions. A peculiar feature of LTBMC is that the stromal cells promote self-renewal as well as differentiation of the stem cells, without the need to add exogenous growth factors. The LTBMC system offers an approach able to investigate not only the proliferative and differentiative events but also sustained cell production and self-renewal of any clonogenic cell types. In the last years, the technique of LTBMC has been increasingly used by several groups to investigate hematopoietic regulation, stromal cell function and the interactions among stromal and hematopoietic cells. In the present report, the biology of LTBMC and their possible clinical applications will be reviewed.

Bone Marrow Cells↗
PubMed1993

Contralateral spontaneous pneumothorax after single lung transplantation for fibrosis.

The authors report the treatment of a case of contralateral spontaneous pneumothorax during single lung transplantation. This is a unusual complication that must be treated to avoid life-threatening problems. There is no consensus of opinion on therapeutic procedures. This work underline the success obtained with a simple thoracostomic drainage.

Adult↗
PubMed1993

Adherence of human monocytes to haemodialysis membranes.

In the present study we evaluated spontaneous and stimulated adherence of human monocytes to regenerated cellulose and polyacrylonitrile (AN69) membranes. Spontaneous adherence at 60 min was significantly higher for regenerated cellulose (28 +/- 2%, P < 0.001) than for AN69 (11 +/- 2) membranes. Stimuli such as bacterial lipopolysaccharide, TNF alpha, interleukin-1 and -6 as well as platelet-activating factor, but not IL-4, significantly enhanced adherence at 60 min to AN69 (28 to 30%). In contrast, adherence was not further inducible in the presence of regenerated cellulose. Both spontaneous and cytokine/bacterial lipopolysaccharide-stimulated adherence were significantly reduced by SDZ-63072, a specific platelet-activating factor receptor antagonist. This difference in sensitivity of monocyte adherence reflects probably the intrinsic ability of regenerated cellulose to provide maximal spontaneous monocyte adhesion. These data suggest that PAF may act as an adherence mediator. This is in line with the ability of regenerated cellulose to directly stimulate monocytes to synthesize platelet-activating factor and with the ability of cytokines and bacterial lipopolysaccharide to stimulate its synthesis. Although AN69 has a low adherence potential, bacterial lipopolysaccharide or cytokines may blunt the biocompatibility of this membrane.

Cell Adhesion↗