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Biomedical subjects

A Pagliuca

Publications and source records attributed to A Pagliuca.

At least 37 records · Page 2Linked to original sources
PubMed2000

The role of apoptosis, proliferation, and the Bcl-2-related proteins in the myelodysplastic syndromes and acute myeloid leukemia secondary to MDS.

Bone marrow CD34(+) cell apoptosis (annexin V), proliferation (Ki-67), and Bcl-2-related protein expression was evaluated by flow cytometry in 102 patients with myelodysplastic syndrome (MDS) and acute myeloid leukemia secondary to MDS (MDS-AML) and in 30 normal donors (NBM). Apoptosis was significantly increased in refractory anemia (RA)/RA with ringed sideroblasts (RARS) (56.9% [20.4%-93.6%]) and refractory anemia with excess blasts (RAEB) (51.2% [25.2%-76. 6%]) compared with NBM (16.7% [3.4%-35.3%], P <.0001). In RA/RARS, apoptosis always exceeded proliferation (Ki-67-positivity, 26.1% [9.5%-47.8%]; apoptosis:proliferation ratio 2.08 [1.15-3.63]); whereas in RAEB, this ratio equalized (1.14 [0.93-2.08]) due to increased proliferation (40.4% [22%-69.5%]). Progression to RAEB in transformation (RAEB-t)/MDS-AML was associated with a significant reduction in apoptosis (22.3% [2.1%-53.2%]; P <.0001) and proliferation (16.8% [1.9%-75.8%); P =.04; ratio 1.69 [0.16-12.21]). Pro-apoptotic (Bax/Bad) versus anti-apoptotic (Bcl-2/Bcl-X) Bcl-2-related protein ratios were increased in RA/RARS compared with NBM (2.57 [1.93-9.42] versus 1.89 [0.65-4.1]; P =.06), whereas disease progression was associated with significantly reduced ratios (1.16 [0.06-3.32]; P <.0001) due primarily to increased Bcl-2 expression. Apoptosis and Bax/Bad:Bcl-2/Bcl-X ratio were inversely correlated with both International Prognostic Scoring System score and cytogenetic risk group; highest levels observed in patients with low score and/or good risk cytogenetics. There was a trend toward an association between Bcl-2-related protein expression and apoptosis (P =.07). This study indicates that MDS progression arises through multiple hits that alter levels of CD34(+) cell apoptosis and proliferation. Early disease is associated with excessive apoptosis and elevated ratio of apoptosis to proliferation. Increased proliferative rates are observed in RAEB, whereas leukemic transformation arises through inhibition of apoptosis rather than excessive cell growth. Although disease progression is accompanied by a fall in pro-apoptotic versus anti-apoptotic Bcl-2-related protein ratios, heterogeneity in patterns of protein expression indicates that factors additional to Bcl-2 family members play a role in the deregulated apoptosis in MDS. (Blood. 2000;96:3932-3938)

Acute Disease↗
PubMed2000

Nonmyeloablative stem cell transplantation for congenital immunodeficiencies.

The optimal approach for stem cell transplantation in children with immunodeficiency has yet to be determined. Conditioning therapy is necessary for reliable engraftment and full immune reconstitution; however, the beneficial effect of cytoreductive conditioning is counterbalanced by increased short- and long-term treatment-related toxicity. Whether bone marrow transplantation with a nonmyeloablative preparative regimen was sufficient for the establishment of donor immune reconstitution, with the resultant correction of disease phenotype, was investigated. Eight patients with severe immunodeficiency states underwent T-cell replete bone marrow transplantation from a human leukocyte antigen-matched unrelated (n = 6) or sibling (n = 2) donor with nonmyeloablative conditioning using a fludarabine-melphalan-anti-lymphocyte globulin-based regimen. All patients had severe organ dysfunction that precluded transplantation with conventional conditioning. All patients were engrafted with predominantly donor hematopoiesis, and the duration of neutropenia was brief. Significant acute graft-versus-host disease (GVHD) did not develop, but one patient had limited chronic GVHD. One patient died of disease recurrence, and 3 have stable, mixed chimerism. At a median follow-up of 1 year, all patients have had good recovery of CD3(+) T-cell numbers, and 6 of 7 evaluable patients have normal phytohemagglutinin stimulation indices. The rate of immune reconstitution is comparable with that of historical controls undergoing standard myeloablative protocols. Two patients with CD40 ligand deficiency now show significant expression, and a patient with adenosine deaminase deficiency has improved deoxy adenosine triphosphate metabolites. In summary, it has been demonstrated that nonmyeloablative stem cell transplantation permits rapid engraftment from both sibling and unrelated donors with minimal toxicity even in the presence of severe organ dysfunction. If long-term immune reconstitution of patients treated with this protocol is demonstrated, it is believed this approach might offer significant advantages compared with standard protocols by combining adequate immune reconstitution with reduced short- and long-term toxicity. (Blood. 2000;96:1239-1246)

Child↗
PubMed2000

Class A helix-loop-helix proteins are positive regulators of several cyclin-dependent kinase inhibitors' promoter activity and negatively affect cell growth.

The class A of basic helix-loop-helix (bHLH) proteins are ubiquitously expressed transcription factors playing a pivotal role in the regulation of cell growth and differentiation. We determined that enforced expression of all four different mammalian members of this family, E12, E47, E2-2, and HEB, suppresses the cell colony-forming efficiency of several cell lines. To gain insights into the mechanisms by which class A bHLH factors affect cell growth, we have investigated their role in the transcriptional regulation of cyclin-dependent kinase inhibitors. We found that p21CIP1/ WAF1, p15INK4B, and p16INK4B promoter sequences contain E-boxes that render these genes competent for class A bHLH-mediated transcriptional activation and Id-mediated repression. The mechanism underlying the class A bHLH-mediated inhibition of cell growth does not involve an arrest of G1 progression in 293T cells. In fact, contrary to what has been found in 3T3 NIH fibroblasts, we found that enhanced expression of class A bHLH proteins led to a decreased proliferation rate by promoting cell death associated with the induction of apoptosis. These findings highlight the role of the class A bHLH proteins as general negative regulators of cell proliferation through a mechanism(s) that involves both enhancement of several cyclin-dependent kinase inhibitor genes expression and promotion of cell death.

Animals↗
PubMed2000

Differential role for Sp1/Sp3 transcription factors in the regulation of the promoter activity of multiple cyclin-dependent kinase inhibitor genes.

Cyclin-dependent kinase inhibitors play a significant role in cell cycle progression and in cellular differentiation and their expression is regulated in different cellular settings. GC-rich regions in the promoter sequences of the cyclin-dependent kinase inhibitor genes p15INK4B and p21CIP1/WAF1 mediate the transcriptional response of these genes to extracellular stimuli. Similar GC-rich sequences in the promoter of the p15INK4A and p16INK4B gene can be targeted for transcriptional inactivation by methylation of cytosine residues. GC-rich regions represent putative target sites for binding of the ubiquitously expressed Sp1 and Sp3 transcription factors. Using a combination of functional and biochemical studies, we analyzed the potential role of the Sp1 and Sp3 factors in the regulation of CDKI p15, p16, and p21 promoter activities. Using transient reporter gene assays, we determined that Sp1 is a strong activator of these promoters, whereas Sp3 functions as a weak transactivator. We have identified multiple protein-binding sites in the proximal promoter sequences of these genes by footprinting analysis. Some of these sites are bound by Sp1 and Sp3, as demonstrated by gel-shift experiments using Sp1/Sp3-specific antibodies, permitting the demonstration that a differential role exists for Sp1 and Sp3 in the regulation of the activity of these promoters.

Animals↗
PubMed2000

An analysis of the effect of chronic GvHD on relapse and survival following allogeneic PBSC transplantation.

BACKGROUND: PBSC are increasingly being used as the source of stem cells in allogeneic transplantation. An increased incidence of chronic GvHD has been suggested following unmanipulated allogeneic PBSC transplantation (PBSCT), however, how this affects overall survival is not yet clear. Our aim was to study the impact of chronic GvHD on survival and relapse following allogeneic PBSCT. METHODS: We have analyzed data from 73 patients undergoing HLA-matched allogeneic PBSCT. GvHD prophylaxis was with CYA and MTX in 97% of patients. We have studied the incidence of chronic GvHD and its affect on relapse and survival in these patients. All patients were at least 100 days post-transplant at the time of analysis. RESULTS: Seventy-three patients were evaluable for analysis of chronic GvHD. The overall incidence of chronic GvHD was 55% (limited in 18% and extensive in 37%). Overall median survival was 991 days, with a 4 year survival rate of 48%. Twelve patients relapsed. Patients with chronic GvHD had a significantly lower incidence of disease relapse (p = 0.005) with a relapse probability of 8% at 3 years, compared with 40% in patients with no chronic GvHD. In addition, the extent of chronic GvHD had a marked effect on survival, patients with limited chronic GvHD had a 4 year survival rate of 83%, compared with 45% in patients with extensive chronic GvHD and 38% in patients with no chronic GvHD. This difference was primarily due to the low incidence of relapse and low mortality seen in patients with limited chronic GvHD. DISCUSSION: The presence and extent of chronic GvHD is an important predictor of outcome following allogeneic PBSCT, in that patients who developed either limited or extensive chronic GvHD had a low risk of disease relapse.

Adolescent↗
PubMed2000

Colchicine: an effective treatment for refractory malignant pericardial effusion.

We report a patient with AL amyloidosis and chemo-resistant light-chain multiple myeloma who developed a progressive malignant pericardial effusion leading to cardiac tamponade. Despite pericardiocentesis and surgical intervention, the pericardial effusion failed to resolve. The administration of oral colchicine produced symptomatic relief within 5 days, with the resolution of pericardial effusion after 14 days of treatment. As the administration of colchicine is simple and the side-effect is usually minimal, further studies are warranted to establish the feasibility of using colchicine to treat malignant pericardial effusion.

Adult↗
PubMed2000

Non-caseating granulomata associated with hypocellular myelodysplastic syndrome.

Non-caseating granuloma (NCG) remains a histopathological hallmark for sarcoidosis. Although the exact mechanism for NCG formation is unknown, the pathogenesis may involve a disordered antigen presentation in the monocyte/macrophage system, functional abnormalities in activated T-lymphocytes and uncontrolled cytokine production. Similar immunological dysfunction has been described in myelodysplastic syndrome (MDS). However, the association of NCG and MDS is rarely documented. We report a case of hypocellular MDS associated with generalized NCG. Despite treatment for both sarcoidosis and tuberculosis, the patient failed to respond. A clonal myeloid disorder which was initially suppressed by T-cell immunosurveillance evolved after treatment with anti-thymocyte globulin. Although the coexistence of sarcoidosis remains a possibility, the lack of supportive clinical evidence of sarcoidosis, the abnormal appearances of the bone marrow, together with the failure to improve on high-dose steroid favour the clonal myeloid disorder as the sole pathology.

Adult↗
PubMed1999

The "G-CSF test": the response to a single dose of granulocyte colony-stimulating factor predicts mobilization of hemopoietic progenitors in patients with hematologic malignancies.

A significant proportion of patients with hematologic malignancies fail to mobilize sufficient hemopoietic progenitor cells (HPC), thereby restricting wider application of autologous transplantation. It would be of considerable use to develop a test that could be used prospectively to assess an individual patient's capacity to mobilize HPC. Twenty-two patients with lymphoma, myeloma, and chronic lymphocytic leukemia were given a single dose of 12 microg/kg SC of granulocyte colony-stimulating factor (G-CSF). Blood colony-forming unit granulocyte-macrophage (CFU-GM) and CD34+ cells were scored prior to the test dose, and 72, 96, and 120 hours later. The patients were then mobilized with a standard cyclophosphamide and G-CSF regimen and had blood stem cells harvested. Patients were categorized as good, poor, or intermediate mobilizers on the basis of the CFU-GM/CD34+ cell harvest content and the number of aphereses required to reach established threshold counts. The outcome of cyclophosphamide/G-CSF mobilization was correlated with the response to the test dose of G-CSF. Good mobilizers had significantly higher peak CFU-GM values and CFU-GM increment in response to the test dose of G-CSF compared to intermediate and poor mobilizers. A peak CFU-GM count of > or = 250/mL identified the good mobilizers; conversely, all poor mobilizers had a peak CFU-GM count of <102/mL. An increment in CD34+ cells counts of > or = 2.5/microL was only observed in good mobilizers. The "G-CSF" test is a reliable test that can be used successfully for the assessment of mobilizable HPC in patients with hematologic malignancies. It can also be used to stratify patients enrolled in trials of mobilizing agents.

Adult↗
PubMed1999

[Urinary calcium excretion in a population of children living in Southern Italy].

BACKGROUND: Very few studies have evaluated the role of urinary calcium excretion as marker of bone metabolism in children. Normative data are lacking in these age groups. METHODS: In a group of 122 children (66 females e 56 males), mean age 108.13 +/- 18.73 months, attending a primary school in Nocera Superiore (Southern Italy) the following parameters were evaluated: sex, age, weight, height, BMI (weight/height2), urinary calcium excretion which was measured as the urinary calcium/creatinine concentration ratio (Uca/cr) in extemporaneous sample of the second urine in the morning. The Uca/cr ratio was not normally distributed in this childhood population. Natural logarithmic transformation was used to analyze the data. RESULTS: The mean value of Uca/cr was 0.125 +/- 0.102 mg/mg. A significant correlation was found between the Uca/cr ratio and sex. The Uca/cr ratio values were higher in girls than in boys. Mean Uca/cr was 0.144 +/- 0.113 mg/mg in females while it was 0.102 +/- 0.083 mg/mg in males ("t"-test: p < 0.05). No correlation was found between the Uca/cr ratio and other variables such as age, height, weight and BMI either in the simple or in the multiple linear regression analysis correcting both for the sex and the age. Data by age-group and sex were reported as percentile tables. CONCLUSIONS: The discussed variations of the Uca/cr in children from different areas and sex confirm the need for reference standards calculated in the different population groups.

Body Mass Index↗
PubMed1998

A role for Sp and helix-loop-helix transcription factors in the regulation of the human Id4 gene promoter activity.

Id family helix-loop-helix (HLH) proteins are involved in the regulation of proliferation and differentiation of several cell types. To identify cis- and trans-acting factors that regulate Id4 gene expression, we have analyzed the promoter regulatory sequences of the human Id4 gene in transient transfections and gel mobility shift assays. We have identified two functional elements, both located downstream from the TATA motif, that control Id4 promoter activity. One element contains a consensus E-box, and we demonstrated that the protein complex binding to the E-box contains the bHLH-zip upstream stimulatory factor (USF) transcription factor. Enforced expression of USF1 leads to E-box-mediated stimulation of promoter activity. The E-box also mediated stimulatory effects of several bHLH transcription factors, and co-expression of Id4 blocked the stimulatory effect mediated by the bHLH factors. A second element is a GA motif, located downstream from the transcriptional start sites, mutation of which resulted in a 20-fold increase in transcriptional activity. Gel-shift analysis and transfections into Drosophila Schneider SL2 cells showed that the repressor element is recognized by both Sp1 and Sp3 factors. These data suggest that Id4 transcription control is highly complex, involving both negative and positive regulatory elements, including a novel inhibitory function exerted by Sp1 and Sp3 transcription factors.

3T3 Cells↗
PubMed1998

Blast counts in blood progenitor cell (BPC) correlate with CD34+ cells and CFU-GM and are useful predictor of haemopoietic recovery after autologous BPC transplantation collections.

Assessment of the quality of blood progenitor cell (BPC) collections is based mainly on CD34+ cell enumeration by flow cytometry, or scoring of granulocyte-macrophage colony-forming cells (CFU-GM). A minimum cell dose for haemopoietic recovery can be defined by both assays; however, the CFU-GM assay can not be used for 'real-time' decisions, whereas CD34+ cell scoring requires facilities and expertise which are not universally available. We have investigated the possibility of using morphologically defined blast cells within BPC harvests as a surrogate marker of harvest haemopoietic stem/progenitor cell content, as well as their correlation with CD34+ cells and CFU-GM within the harvests. We have found that blast counts correlate strongly with both CD34+ cell counts and CFU-GM within BPC harvests, as well as with time to granulocyte and platelet recovery after autologous BPC transplantation (ABPCT). Furthermore, we have defined a threshold value of 1.3 x 10(6)/kg blasts, above which there is a high probability of rapid haemopoietic recovery after ABPCT. We conclude that blast count is a simple, rapid and reliable method of assessing BPC harvest quality.

Antigens, CD34↗
PubMed1998

Variable expression of CD3-zeta and associated protein tyrosine kinases in lymphocytes from patients with myeloid malignancies.

In myeloid malignancies, T-cell and NK function has been shown to deteriorate with transformation from pre-leukaemia to advanced disease. Immune dysfunction in solid tumours has been attributed to abnormal signal transduction, possibly through altered expression of intracellular components of the TCR/CD3 complex (e.g. CD3-zeta), receptors on NK cells and their associated protein tyrosine kinases (PTKs; p56lck, p59fyn and ZAP-70). Using a flow cytometric method to detect dual-expression of surface proteins and intracellular components of the TCR/CD3 complex, we have studied 46 patients with myeloid malignancies. CD3-zeta expression was abnormal in 64% of patients, and was more prominent in those with advanced disease. Three patients with reduced CD3-zeta were analysed both pre- and post-treatment, and recovery of CD3-zeta expression was associated with successful remission induction (expression of PTKs was variable and reduced levels were seen all disease stages). The results of this study suggest that loss of signalling proteins is not a result of direct contact of leukaemic cells with lymphocytes per se or the extent of the leukaemia burden, but to a specific property of some myeloid malignancies, which is more frequently acquired with greater malignant transformation.

Adult↗
PubMed1998

'Low-risk' myelodysplastic syndrome is associated with excessive apoptosis and an increased ratio of pro- versus anti-apoptotic bcl-2-related proteins.

We performed flow cytometric analysis of CD34+ cell apoptosis in 59 patients with myelodysplastic syndrome (MDS) or acute myeloid leukaemia (AML) secondary to MDS (MDS-AML) using annexin V-FITC, which binds to exposed phosphatidylserine on apoptotic cells. Apoptosis was significantly increased in FAB subtypes RA, RARS and RAEB (<10% blasts) (56.5% (15.1-86.5%)) compared to normal controls (18.5% (3.4-33.4%), P<0.0001) and RAEB-t/MDS-AML (16% (2.1-43.2%), P<0.0001). There was no correlation between % apoptosis, Full blood count or cytogenetics in any disease category. Two-colour cytometric analysis of permeabilized CD34+ cells stained with antibodies to Bcl-2, Bcl-X (anti-apoptotic), Bax and Bad (pro-apoptotic), demonstrated significantly higher ratios of pro- v anti-apoptotic proteins in early MDS (2.47 (1.19-9.42) compared to advanced disease (1.14 (0.06-3.32), P=0.0001). Moreover, using repeated measures of variants (ANOVA), we found that variations between individual Bcl-2-related proteins differed significantly according to disease subtype (P<0.0005). Our results confirm that CD34+ cell apoptosis was significantly increased in MDS subtypes RA and RARS and fell with disease progression. Early MDS was also associated with a significantly higher CD34+ cell pro- v anti-apoptotic Bcl-2-family-protein ratio than advanced disease. Furthermore, patterns of expression of individual Bcl-2 related proteins differed significantly between different disease categories. However, no correlation between pro- v anti-apoptotic Bcl-2-family-protein ratios and the degree of apoptosis was observed.

Acute Disease↗