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Biomedical subjects

G d'Onofrio

Publications and source records attributed to G d'Onofrio.

At least 19 recordsLinked to original sources
PubMed2006

Slight association between type 1 diabetes and "ff" VDR FokI genotype in patients from the Italian Lazio Region. Lack of association with diabetes complications.

BACKGROUND: Vitamin D receptor (VDR) mediates the effects of vitamin D. Our paper evaluates the FokI and BsmI VDR genotypes in 246 Caucasian (Italian from Lazio Region) T1DM patients compared with 246 Caucasian healthy controls, sharing age and gender and regional provenience with the patients. In addition, T1DM patients without complications were compared with those carrying three complications. METHODS: Genotyping has been obtained by RFLP-PCR technique. RESULTS: A slight significant association of T1DM with FokI homozygous "f" genotype was observed. No association was observed with the presence of multiple complications by a multivariate analysis. CONCLUSION: T1DM patients showed slightly increased prevalence of "ff" VDR genotype.

Adult↗
PubMed2006

Aetiological factors related to a positive direct antiglobulin test result in human immunodeficiency virus-infected patients.

BACKGROUND AND OBJECTIVES: The aim of this study was to examine the clinical importance and causes of a positive result in the direct antiglobulin test (DAT) in human immunodeficiency virus-infected (HIV(+)) patients. We therefore studied haematological parameters in outpatient samples, and also analysed the impact of highly active anti-retroviral therapy (HAART) on the DAT results. STUDY DESIGN AND METHODS: Haematological parameters, clinical stages, chemo-antibiotic treatments and HAART treatment were studied to determine any relationships with DAT results in 115 consecutive HIV(+) patients. RESULTS: Significantly lower haemoglobin (Hb) levels were detected in patients with HIV who had a positive DAT result. Hepatitis C virus (HCV) co-infection (odds ratio 2.529) and trimethoprim-suphamethoxazfole (TMP-SMX) prophylaxis (odds ratio 3.751) had a significant association with DAT positivity. Patients receiving HAART were less likely to have a positive DAT [odds ratio (OR) 0.383; P = 0.035]. Among the patients treated with TMP-SMX, those with a positive DAT had lower Hb levels (11.9 g/dl) than those with a negative DAT (14.2 g/dl; P = 0.04). HCV antibody positivity and TMP-SMX prophylaxis showed a cumulative effect on positive DATs (OR 4.533). The surface exploratory analysis indicated the distribution of the positive DATs in relationship with the CD4(+) count and Hb levels. CONCLUSIONS: Significantly lower Hb levels were detected in DAT-positive HIV(+) patients. HCV co-infection and TMP-SMX prophylaxis appear to confer an increased risk of DAT positivity. The presence of red blood cell autoantibodies may be associated with anaemia in HIV disease in the absence of overt haemolysis.

Anemia↗
PubMed2003

International Council for Standardization in Haematology (ICSH) recommendations for "surrogate reference" method for the packed cell volume.

The spun packed cell volume (PCV, hematocrit) is a key measurement on which are based hematology instrument calibration, reference range determination, and assignment of values to calibrators/controls. In 2001, the International Council for Standardization in Haematology (ICSH) recommended a Reference PCV method, which is fully traceable to the ICSH reference hemoglobin method. Because of its complexity, however, this method is impractical for occasional use in routine laboratories and is therefore intended primarily for use by manufacturers of capillary microhematocrit tubes, liquid calibrators, and multichannel analyzers. In response to the need for a simpler method--accessible to all routine laboratories--the ICSH offers this "Surrogate Reference" PCV procedure. It is traceable to the original ICSH Reference PCV method and is based on spun PCVs obtained using borosilicate capillary tubes with an already-known relationship to this reference procedure. This ICSH "Surrogate Reference" PCV method is substantially simpler, thus putting it within the reach of most routine hematology laboratories.

Blood Specimen Collection↗
PubMed2000

Enhanced susceptibility to apoptosis in T cells recovering after autologous peripheral blood progenitor cell transplantation: reversal by interleukin-15.

T-cell number and competence are profoundly impaired after transplantation of autologous cytokine-mobilized peripheral blood progenitor cells (PBPC). The objective of the present study was to evaluate the occurrence of T-cell spontaneous apoptosis (Aspont) and its modulation in vitro by the interleukin-2 receptor (IL-2R) gamma-chain (gammac)-signaling cytokine interleukin-15 (IL-15) in the peripheral blood of patients transplanted with autologous PBPC for hematological malignancies. An average 45%+/-6% of CD4+ and 55%+/-6% of CD8+ T cells cultured in the absence of exogenous cytokines underwent Aspont; of interest, IL-15 and, to a lesser extent, its structural cousin IL-2 counteracted T-cell Aspont and upregulated Bcl-2 levels. IL-15 did not rescue T cells from Aspont by promoting proliferation, but rather it acted as a genuine survival factor. Furthermore, T-cell preincubation with a gammac-blocking antibody was capable of abrogating both apoptosis inhibition and Bcl-2 induction by IL-15. These in vitro findings suggest that IL-15 might represent a promising immunomodulating agent to improve T-cell function after autologous PBPC transplantation.

Adult↗
PubMed1998

Guidelines for organisation and management of external quality assessment using proficiency testing. Expert Panel on Cytometry of the International Council for Standardization in Haematology.

This document is intended to assist towards the WHO objective that external quality assessment (EQA) schemes be established at national and/or regional levels world-wide. Quality assurance is defined as all steps taken by the director of a laboratory to ensure reliability of laboratory results and to increase accuracy, reproducibility and between-laboratory comparability. This includes the use of internal quality control procedures and participation in external quality assessment. Internal quality control provides the means for evaluation of analytic test results at the time of testing in order to decide whether they are reliable enough to be released to the requesting clinicians. EQA, on the other hand, refers to a system of retrospective and objective comparison of results from different laboratories by means of proficiency testing (PT) organised by an external agency. The main purpose is to establish between-laboratory and between-method (including between-instrument) comparability, and agreement with a reference standard where one exists. Internal quality control and EQA complement each other and must never be considered as alternatives.

Animals↗
PubMed1998

Highly fluorescent reticulocytes after CD34+ peripheral blood progenitor cell transplantation.

Highly fluorescent reticulocyte (HFR) counts were evaluated in 13 consecutive patients affected by hematological malignancies and submitted to autologous selected CD34+ peripheral blood progenitor cell (PBPC) transplantation. Results were compared with a historical group of patients comparable for age, disease and conditioning regimen submitted to unfractionated PBPC transplantation. HFR counts of the CD34+ group declined to an undetectable level from day +4 to day +10 when they became detectable and reached 5% of total reticulocyte count by day +12. In the historical group, the nadir was identical but the recovery was faster (day +9). Total reticulocyte count > 1% was achieved at days +17 and +11, respectively. The absolute neutrophil count (ANC) recovery was identical in both groups, achieving a value > 0.5 x 10(9)/l at day +13 after reinfusion. Hence, in the historical group, HFR count gave advance notice of complete and stable hemopoietic engraftment while in the CD34+ group HFR and ANC count showed almost simultaneous recovery.

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

Evaluation of the Abbott Cell Dyn 4000 automated fluorescent reticulocyte measurements: comparison with manual, FACScan and Sysmex R1000 methods.

The Abbott Cell Dyn 4000 (CD4000) is the first haematology analyser in which fully-automated reticulocyte measurements can be routinely determined by fluorescence as part of the full blood count. This communication reports the first evaluation of this method which was undertaken by three independent reference laboratories in Belgium, Germany and Italy. A total of 695 different samples was entered into the study which was designed to compare CD4000 reticulocyte information (enumeration and qualitative maturational data) with results determined in parallel with the existing manual (supravital staining) reference procedure, and two semi-automated fluorescent assays (Becton Dickinson FACScan and Sysmex R1000 instruments). These studies revealed good agreement between the CD4000 and the manual procedure, with no inter-method bias. Comparison of CD4000 and FACScan reticulocyte measurements, however, indicated a distinct tendency for the FACScan to give higher reticulocyte estimates than the CD4000. Finally, the comparison of the CD4000 with the Sysmex R1000 showed excellent agreement in the range 0-6% reticulocytes, although there was some inter-method bias in the higher range (> 15%). Analysis of agreement levels between the methods using specific 'clinical decision points' confirmed the tendency for overestimation by the FACScan, in that 58% of the samples with a reticulocytopenia of < 0.5% as defined by the CD4000 gave FACScan results within the normal range (0.5-1.8%). In contrast, there was absolute agreement between the CD4000 and the Sysmex R1000 for all reticulocytopenias. Comparison (195 samples) of instrument fluorescent reticulocyte maturation profiles demonstrated an exponential relationship (r = 0.78) between CD4000 IRF and R1000 HFR (highly fluorescent reticulocyte fraction) values. The suggestion that the CD4000 IRF values includes some of the MFR as well the HFR reticulocyte fraction was confirmed as the correlation between the CD4000 IRF and the Sysmex R1000 MFR plus HFR percentages was linear (r = 0.82). This study confirms a high performance level for the CD4000 automated fluorescent reticulocyte method.

Autoanalysis↗
PubMed1996

The combination of erythropoietin and granulocyte colony-stimulating factor increases the rate of haemopoietic recovery with clinical benefit after peripheral blood progenitor cell transplantation.

In order to investigate the effects of erythropoietin (EPO) plus granulocyte colony-stimulating factor (G-CSF) administration after peripheral blood progenitor cell transplantation (PBPCT) we performed a phase I/II study in patients with high-risk cancer. 15 consecutive patients were treated wit recombinant human G-CSF (rhG-CSF) at the dose of 5 micrograms/kg subcutaneously (s.c.) every 24 h until day + 12 and with recombinant human EPO (rhEPO) at the dose of 150 IU/kg s.c. every 48 h until day + 11 following PBPCT. Their haemopoietic recovery was compared to that obtained in eight historic and control patients who did not receive any cytokines after PBPCT. No side-effects were observed during EPO plus G-CSF treatment and the treatment was not discontinued in any of the patients before completion of the treatment plan. The administration of EPO plus G-CSF after PBPCT produced a significant increase in the rate of white blood cell (WBC) (P = 0.0005), polymorphonuclear leucocyte (PMN) (P = 0.0005) and platelet (PLT) (P = 0.0105) recovery compared to the control group. The acceleration in haemopoietic recovery observed in the EPO plus G-CSF-treated patients produced a significant reduction of the days with WBC < 1 x 10(9)/l (P = 0.0009), PMN < 0.2 x 10(9)/l (P = 0.0030) and PMN < 0.5 x 10(9)/l (P = 0.0006). EPO plus G-CSF-treated patients required a significantly lower number of single donor PLT transfusions (P = 0.0142) and did not experience neutropenic fever, but historic control patients experienced fever > 38 degrees C for a median period of 4 d (0-12) with a medial period of parenteral antibiotic administration of 7.5 d (0-17). The length of the hospital stay was significantly shorter in the study group than in the historic control group (P = 0.0264). In conclusion, we can confirm that EPO plus G-CSF treatment is feasible and potentiates the haemopoietic recovery after PBPCT, thus simplifying the clinical management of cancer patients who undergo high-dose chemotherapy.

Adult↗
PubMed1996

Reticulocytes in haematological disorders.

The increased precision of flow cytometric techniques permits the recognition of small differences even in the low or normal range of the reticulocyte count. Moreover, measurement of the RNA content of reticulocytes makes possible the identification of the youngest highly fluorescent macroreticulocytes (HFR) prematurely delivered from bone marrow in conditions of increased erythropoietic stimulation. The aim of this study was the definition, using the dedicated flow cytometers Sysmex R-1000 or R-3000 (Toa Medical Electronics Ltd, Kobe, Japan), of reticulocyte absolute number and HFR percentage in patients with haematological disorders prior to any treatment. Analysis of 54 healthy subjects and 100 untreated patients with five types of haematological disease is presented. In haemolytic anaemias (15 cases) both the reticulocyte count and HFR were greatly increased and the reticulocyte count was inversely correlated with Hb level, as in the reference population. In polycythaemia vera (20 cases) reticulocytes were moderately increased and directly correlated with Hb. In dyserythropoietic syndromes (20 cases) reticulocytes were low and HFR moderately increased; HFR showed an inverse correlation with Hb. In acute myeloid leukaemia (30 cases) reticulocytes were low and HFR increased; reticulocytes correlated with both HFR and Hb. In acute lymphoid leukaemia (15 cases), while the reticulocyte count did not differ from the reference group, the HFR was increased. These results provide reference values for the evaluation of reticulocyte counts and HFR in haematological diseases. From a physiopathological standpoint, they suggest that in anaemic patients the reticulocyte count directly reflects effective bone marrow erythrocyte production, while the proportion of circulating HFR more closely reflects the intensity of erythropoietic stimulation.

Adult↗
PubMed1996

Assessing erythropoiesis and the effect of erythropoietin therapy in renal disease by reticulocyte counting.

Renal disease is characterized by failure of erythropoietin (Epo) production and low bone marrow sensitivity to Epo. The reticulocyte count is the best laboratory marker of erythropoiesis available, but reticulocytes have not been extensively studied in renal disease. Cluster analysis suggests that in non-haemodialysed renal patients the anaemia is associated with uraemia while the reticulocyte number and immature subclasses are correlated with the ineffective erythropoietic component of the anaemia. This emphasizes the importance of treating the renal disease in patients with the anaemia of end-stage renal failure. Human recombinant Epo therapy has been demonstrated to be effective in correcting anaemia in most cases of chronic renal insufficiency. In renal patients the reticulocyte count should only be monitored by automated methods to assure reliability at low counts.

Anemia↗