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Paolo Rebulla

Publications and source records attributed to Paolo Rebulla.

At least 19 recordsLinked to original sources
PubMed2006

The risk of bleeding in thrombocytopenic patients with acute myeloid leukemia.

BACKGROUND AND OBJECTIVES: Patients with acute myeloid leukemia are at risk of bleeding. The risk factors for different severities of bleeding are poorly studied. DESIGN AND METHODS: Data from Rebulla et al. were analyzed in an exploratory analysis using multivariate Cox regression analyses for time-to-first bleed with time-depend- ent covariates reflecting measures of clinical and laboratory variables on the previous day. The relationships of the variables with three bleeding categories were studied: mild bleeding (WHO grades 1 and 2) clinically significant (bleeding grades 2, 3 and 4) and severe (bleeding grades 3 and 4). RESULTS: Bleeding of any severity occurred in 149 (58.4%) of 255 patients. There were 743 days of bleeding over 7335 patient-days of observation. Risk factors for mild bleeding included increased body temperature and decreased platelet count; the risk was decreased with administration of antifungal medication or platelet transfusion on the previous day. Risk factors for clinically significant bleeding included grade 1 bleeding on the previous day, decreased platelet count and elevated body temperature. Decreased platelet count and mild bleeding on the previous day were risk factors for severe bleeding. Higher hemoglobin values were associated with a delay in the time-to-first clinically significant bleed. INTERPRETATION AND CONCLUSIONS: These results support clinical guidelines for increasing the platelet transfusion threshold in the presence of fever and support the use of milder bleeding symptoms as an outcome in clinical trials. The suggestion that hemo- globin concentration maybe predictive of bleeding risk supports the hypothesis that this maybe a valuable intervention in anemic thrombocytopenic patients at high risk of bleeding.

Adolescent↗
PubMed2006

Development of a mock hemopoietic stem cell component suitable for the validation of cryopreservation procedures.

We developed a laboratory model of a unit of hemopoietic progenitor cells (mock-HPC unit) suitable for the validation of HPC cryopreservation procedures. The project was prompted by the practical and ethical difficulty of using real HPC units collected from healthy donors and patients for validation purposes. Mock-HPC units of different volumes ranging from about 120 to about 540mL were prepared by pooling a routinely discarded by product of our procedure to prepare platelet concentrates from buffy-coats, a standard procedure in most blood centers in Europe. Five ABO/Rh identical buffy coats each of 50mL volume, obtained from 450mL whole blood units by hard spin, were pooled with 300mL of a commercial platelet additive solution. After soft spin, the supernatant platelet concentrate pool was removed. The bottom fraction of this procedure, which contains RBC, WBC, HPC and platelets, constitutes a mock-HPC unit of about 120mL volume. Several bottom fractions may be pooled to obtain a mock-HPC unit of the desired volume. We used 20 mock-HPC units to validate an automatic procedure of HPC cryopreservation with a controlled rate freezer. In particular, we documented the standardization of critical points of the cooling profile, such as the correspondence of the crystallization phase with the theoretical freezing temperature of the product, the temperature peak rise above the theoretical freezing temperature of -5.7 degrees C and the automatic achievement in the chamber of a constant minimum temperature during supercooling (about -37 degrees C) with mean chamber loading volumes ranging from 231.8 to 1027.2mL.

Blood Preservation↗
PubMed2006

Serial transplantations in nonobese diabetic/severe combined immunodeficiency mice of transduced human CD34+ cord blood cells: efficient oncoretroviral gene transfer and ex vivo expansion under serum-free conditions.

Stable oncoretroviral gene transfer into hematopoietic stem cells (HSCs) provides permanent genetic disease correction. It is crucial to transplant enough transduced HSCs to compete with and replace the defective host hemopoiesis. To increase the number of transduced cells, the role of ex vivo expansion was investigated. For a possible clinical application, all experiments were carried out in serum-free media. A low-affinity nerve growth factor receptor (LNGFR) pseudotyped murine retroviral vector was used to transduce cord blood CD34(+) cells, which were then expanded ex vivo. These cells engrafted up to three generations of serially transplanted nonobese diabetic/severe combined immunodeficiency mice: 54.26% +/- 5.59%, 19.05% +/- 2.01%, and 6.15% +/- 5.16% CD45(+) cells from primary, secondary, and tertiary recipient bone marrow, respectively, were LNGFR(+). Repopulation in secondary and tertiary recipients indicates stability of transgene expression and long-term self-renewal potential of transduced HSCs, suggesting that retroviral gene transfer into HSCs, followed by ex vivo expansion, could facilitate long-term engraftment of genetically modified HSCs.

Animals↗
PubMed2006

Molecular and phenotypic characterization of human amniotic fluid cells and their differentiation potential.

The main goal of the study was to identify a novel source of human multipotent cells, overcoming ethical issues involved in embryonic stem cell research and the limited availability of most adult stem cells. Amniotic fluid cells (AFCs) are routinely obtained for prenatal diagnosis and can be expanded in vitro; nevertheless current knowledge about their origin and properties is limited. Twenty samples of AFCs were exposed in culture to adipogenic, osteogenic, neurogenic and myogenic media. Differentiation was evaluated using immunocytochemistry, RT-PCR and Western blotting. Before treatments, AFCs showed heterogeneous morphologies. They were negative for MyoD, Myf-5, MRF4, Myogenin and Desmin but positive for osteocalcin, PPARgamma2, GAP43, NSE, Nestin, MAP2, GFAP and beta tubulin III by RT-PCR. The cells expressed Oct-4, Rex-1 and Runx-1, which characterize the undifferentiated stem cell state. By immunocytochemistry they expressed neural-glial proteins, mesenchymal and epithelial markers. After culture, AFCs differentiated into adipocytes and osteoblasts when the predominant cellular component was fibroblastic. Early and late neuronal antigens were still present after 2 week culture in neural specific media even if no neuronal morphologies were detectable. Our results provide evidence that human amniotic fluid contains progenitor cells with multi-lineage potential showing stem and tissue-specific gene/protein presence for several lineages.

Adipogenesis↗
PubMed2006

A descriptive analysis of international transfusion practice and bleeding outcomes in patients with acute leukemia.

BACKGROUND: Recently, bleeding has been used in platelet (PLT) trials rather than surrogate outcomes. The purpose of this study was to provide a descriptive summary of data from PLT studies conducted in four countries and exploratory analyses to determine the relationship between bleeding and PLT count. STUDY DESIGN AND METHODS: A descriptive analysis was performed on original data from the Italian trigger study, the US TRAP study, the Canadian febrile reaction study, and a clinical chart review from one hospital site in the United Kingdom. The relationship between bleeding and PLT count was explored with the Italian data. RESULTS: A total of 897 patients with acute leukemia received 10,506 PLT transfusions. Grade 3 or Grade 4 WHO bleeding frequency was 28.1 percent (252/897) but varied by country: Italy, 10.8 percent (27/250); United States, 36.4 percent (217/598); Canada, 18.9 percent (7/37); and the United Kingdom, 8.3 percent (1/12). Grade 1 or Grade 2 bleeding was reported only in the Italian study (46.4%[116/250] and 11.6%[29/250], respectively). The relative rates of WHO Grade 2, 3, or 4 bleeding for PLT counts in the ranges of 0 to 4, 5 to 9, 10 to 14, and 15 to 19 (x10(9)/L) were 8.8, 1.9, 1.8, and 1.2, respectively, compared to those counts within the range of 20 to 29 (x10(9)/L). CONCLUSION: The study provides descriptive data on PLT use and frequency of bleeding. When PLT counts were 0x10(9) to 4x10(9) per L there was an eightfold increase in bleeding and a twofold risk increase when counts were 5x10(9) to 14x10(9) per L compared to the 20x10(9) to 29x10(9) per L reference range. The increased rate of bleeding at low counts occurred despite PLT therapy.

Acute Disease↗
PubMed2006

Endothelial colony forming capacity is related to C-reactive protein levels in healthy subjects.

The majority of clinical studies on endothelial progenitor cells (EPCs) focuses on the role of these cells in cardiovascular diseases and no systematic studies exist regarding their variations in healthy subjects. In order to define the burden of angiogenesis in physiological conditions we assessed the frequency of peripheral blood endothelial colonies (PB-ECs) and their relation with other factors possibly involved in their function such as high-sensitivity C-reactive protein (hs-CRP), endothelial cell-specific mitogen factor (VEGF) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in a highly selected healthy population. A PB sample was obtained from 37/47 healthy subjects (age 40.2+/-15.0yrs; M/F 15/22) without known cardiovascular risk factors. The serum level of hs-CRP, VEGF, TIMP-1, the frequency of PB-ECs by clonogenic assay, and the number of early EPCs and late EPCs by flow cytometry analysis were evaluated. PB-ECs were formed by 40.5% of studied subjects with a mean of 0.40+/-0.82 colonies/10(6) cells. The differences in the frequency of colony formation between genders were not statistically significant. The subjects with PB-ECs were characterized by higher values of hs-CRP, when compared with those not forming colonies, 0.276+/-0.230 vs 0.095+/-0.077 mg/l (p=0.003) respectively, and of VEGF, 328.3+/-162.9 vs 202.68+/-118.53 pg/ml (p=0.02). No significant differences were found in TIMP-1 values. The EPC clonogenic potential seems to be related to hs-CRP and VEGF levels even in healthy population supporting the concept that these mediators are involved in physiological ECs function.

Adult↗
PubMed2005

A mini-review on platelet refractoriness.

BACKGROUND: Lack of adequate post-transfusion platelet count increments - platelet refractoriness - is a complication of chronic platelet support shown by 5-15% of chronic platelet recipients. INFORMATION SOURCES. To review the frequency, diagnosis, management and cost of platelet refractoriness, particularly as described in English literature published during 2000-2004 and searched with Pubmed. RESULTS: Refractoriness is usually defined as the occurrence of 2-3 post-transfusion platelet count increments, corrected for the patient's size and number of administered platelets, at 10-60 minutes and at 18-24 hours post-transfusion below 4,500-5,000 and 2,500 platelets per microliter respectively. In most cases refractoriness is associated with clinical and pharmacological causes. In those cases in which refractoriness is due to immune factors, anti-HLA antibodies are most frequently implicated. Validated strategies to select effective platelets for alloimmunized refractory patients include the selection of HLA-matched platelet donors from HLA-typed donor registries and the use of manual or automated platelet cross-matching. Both strategies, which require significant organizational and financial resources, can provide successful platelet support in about 2/3 of transfusions. INTERPRETATION AND CONCLUSIONS: Unlike the less frequent cause of platelet refractoriness (anti-HLA alloimmunization) whose detrimental effect can be overcome by using HLA compatible platelets, the main causes of platelet refractoriness (patient's poor clinical condition and the use of drugs affecting platelet survival and function) remain largely unresolved.

Blood Platelets↗
PubMed2004

Identification of preleukemic precursors of hyperdiploid acute lymphoblastic leukemia in cord blood.

Previous studies involving identical twins with concordant leukemia and retrospective scrutiny of archived neonatal blood spots have shown that common chromosome translocations of pediatric leukemia frequently arise before birth. The IGH/TCR clonotypic sequences used as surrogate molecular markers suggest this is also likely to be true for hyperdiploid acute lymphoblastic leukemia (ALL). Yet evidence that hyperdiploidy itself is an early or initiating event occurring prenatally has been limited. Now, however, we can provide direct evidence of this from our identification of CD34+/CD19+ B-lineage progenitor cells with triploid chromosomes in the stored cord blood of an individual who subsequently developed hyperdiploid ALL.

Antigens, CD19↗
PubMed2004

Factors associated with outcomes of unrelated cord blood transplant: guidelines for donor choice.

OBJECTIVE: Optimizing cord blood donor selection based mainly on cell dose and human leukocyte antigen (HLA) disparities may further improve results of unrelated cord blood transplants (UCBT). MATERIALS AND RESULTS: We analyzed 550 UCBTs for hematologic malignancies reported to the Eurocord Registry. Main outcomes and prognostic factors were analyzed in univariable and multivariable analyses incorporating center and period effects and using death and relapse as competitive risks for nonfatal endpoints. Nucleated cell (NC) dose before freezing and number of HLA disparities had a significant influence on outcome. Cumulative incidence (CI) of neutrophil and platelet recovery was associated with the number of HLA mismatches, number of NC before freezing, and use of granulocyte colony-stimulating factor. Coexistence of HLA class I and II disparities and high CD34 cell dose in the graft were associated with graft-vs-host disease grades III-IV. CI of disease relapse was higher in matched transplants showing a graft-vs-leukemia effect increased in HLA-mismatched transplants. Overall 3-year survival was 34.4%. Prognostic factors for survival were recipient age, gender, and disease status. CONCLUSION: Our results provide indications for a better choice of cord blood units according to cord blood cell content and HLA.

Adolescent↗
PubMed2004

Review of the quality monitoring methods used by countries using or implementing universal leukoreduction.

Several countries are implementing or have implemented universal leukoreduction (ULR). Specifications, leukocyte counting, and monitoring methods were essential elements in achieving process confidence and conformance. A review of these protocols is presented. A questionnaire was prepared, agreed, and circulated, and responses were collated. Different specifications have been adopted as well as disparate approaches to leukocyte counting and residual leukocyte monitoring. Parametric, nonparametric, and pass-rate methods of analysis were used. Despite these differences, users were satisfied that the methodologies were providing assurance of component quality.

Cell Separation↗
PubMed2004

Immune hemolytic anemia associated with teicoplanin.

BACKGROUND: Several drugs can cause immune hemolytic anemia. Here a patient who developed hemolytic anemia after treatment with teicoplanin is described. CASE REPORT: Owing to a two-vessel disease, a 68-year-old white man underwent coronary artery bypass grafting. He was readmitted for superficial sternal wound infection and sternal instability. Rewiring was required and worsening anemia characterized the course after the reoperation. Drugs used in the second admission were gentamycin, teicoplanin, paracetamol, and codeine. They were considered as a possible cause of drug-induced hemolytic anemia. RESULTS: The DAT was positive for complement and IgG. Autoanti-e was identified in the patient's undiluted serum sample. The eluate was reactive with all RBCs tested only after adding teicoplanin; when diluted 1:4, anti-e specificity was observed in the presence of teicoplanin. CONCLUSION: To our knowledge, this is the first report of immune hemolytic anemia owing to teicoplanin.

Aged↗
PubMed2004

Outcomes of an automated procedure for the selection of effective platelets for patients refractory to random donors based on cross-matching locally available platelet products.

In 1999, we implemented an automated platelet cross-matching (XM) programme to select compatible platelets from the local inventory for patients refractory to random donor platelets. In this study, we evaluated platelet count increments in 40 consecutive refractory patients (8.3% of 480 consecutive platelet recipients) given 569 cross-match-negative platelets between April 1999 and December 2001. XM was performed automatically with a commercially available immunoadherence assay. Pre-, 1- and 24-h post-transfusion platelet counts (mean +/- SD) for the 569 XM-negative platelet transfusions containing 302 +/- 71 x 109 platelets were 7.7 +/- 5.5, 32.0 +/- 21.0 and 16.8 +/- 15.5 x 109/l respectively. Increments were significantly higher (P < 0.05, t-test) than those observed in the same patients given 303 random platelet pools (dose = 318 +/- 52 x 109 platelets) during the month before refractoriness was detected, when pre-, 1- and 24-h post-transfusion counts were 7.0 +/- 8.6, 15.9 +/- 16.1 and 9.6 +/- 12.8 x 109/l respectively. The cost of the platelet XM disposable kit per transfusion to produce 1-h post-transfusion platelet count increments >10 x 109/l was euro 447. This programme enabled the rapid selection of effective platelets for refractory patients, from the local inventory.

Adolescent↗
PubMed2004

The translocation of marrow MNCs after experimental myocardial cryoinjury is proportional to the infarcted area.

BACKGROUND: The selective homing of peripherally injected marrow MNCs (MMNCs) has recently been demonstrated in a model of cryodamaged heart. However, the mechanism underlying this phenomenon is still unknown. In the hypothesis that this process is related to the necrotic area extension, the infarcted area was correlated with the number of homed MMNCs in a model of experimental cryodamaged heart. STUDY DESIGN AND METHODS: A total of 12 donor and 12 recipient inbred isogenic adult (4 weeks old) Fisher rats were used to mimic autologous transplantation. Myocardial damage was obtained in recipient rats by cryoinjury. MMNCs were purified, labeled with PKH26 (a red fluorescent cell dye), and infused 7 days after the injury through the femoral vein of recipient rats. One week after peripheral administration, the number of homed MMNCs was assessed and the infarct size was correlated with the number of cells present in the target. RESULTS: Labeled cells were found only in the injured myocardium of the treated animals (n = 6), where a mean of 12 +/- 3 PKH26+ cells per section examined were found; a significant correlation was found between the infarct size and the estimated number of cells (p = 0.008) CONCLUSION: These data indicate that the homing of MMNCs is related to the extent of the myocardial injury, suggesting that cellular therapy for regeneration of damaged myocardium should be individualized by taking into consideration the extension of the area to repair.

Animals↗
PubMed2004

Flow-cytometric approach to the prompt laboratory diagnosis of TRALI: a case report.

OBJECTIVES: Transfusion-related acute lung injury (TRALI) is a rare but serious complication which can occur after transfusion of blood components. In this report we describe our flow-cytometry approach to the laboratory diagnosis of a case of TRALI in a recipient of fresh frozen plasma containing human leukocyte antigen (HLA) class II antibodies. METHODS: The post-transfusion reaction work-up included the direct and indirect Granulocyte Immunofluorescence Test (GIFT) on the recipient's neutrophils collected before and after the reaction and on the serum from the recipient and from all implicated donors; flow-cytometry bead-based screening and identification assay for HLA class I and II antibodies in donor sera and flow cytometry cross-matching on T and B patient's lymphocytes. Finally, we investigated the reactivity of one donor serum, containing HLA class II antibodies, with the patient's neutrophils activated in vitro to induce expression of HLA class II. RESULTS: We found an increased level of IgG bound on patient's granulocytes collected after TRALI, in the absence of detectable granulocyte and HLA class I antibodies in the five implicated donors. One of them showed HLA-DR 1 and -DR 51 antibodies, which determined a positive cross-match with patient's B lymphocytes and in vitro activated granulocytes. Both HLA class II antigens were present in the recipient and absent in the donor. CONCLUSIONS: In some pathological conditions, HLA class II antibodies can react with activated granulocytes expressing HLA-DR antigens, and activate TRALI reaction. HLA class II antibodies screening and flow cytometry cross-matching techniques should be added to the current diagnostic algorithm of TRALI.

Aged↗
PubMed2004

Clinical and histological characterization of liver disease in patients with transfusion-dependent beta-thalassemia. A multicenter study of 117 cases.

BACKGROUND AND OBJECTIVES: Updated information on liver disease in transfusion-dependent beta-thalassemia is lacking. We conducted a multicenter study within the Cooleycare Group to describe the clinical and histopathological features of liver disease in currently treated thalassemics. DESIGN AND METHODS: Two-hundred and three thalassemics with laboratory signs of liver disease were eligible. Liver biopsy was performed in the 129 (63.5%) who consented (age 26+/-7 years). Biological samples were sent to the central laboratory. RESULTS: Anti-hepatitis C virus (HCV) antibodies were found in 118 patients (91%), 85 (72%) of whom were viremic. Ninety-one patients (70%) had abnormal aminotransferase concentrations. In the 117 liver biopsies that met the criteria for evaluation (88%), the median Ishak's necroinflammatory and fibrosis scores were 4 (range, 0-9) and 2 (range, 0-6), respectively. Significant fibrosis (score >or=3) was found in 53 (45%); 9 (8%) had cirrhosis. At multivariate analysis, necroinflammation was related to HCV viremia, and fibrosis to increased serum aminotransferases, higher iron stores (including serum ferritin, Deugnier's total iron score, and liver iron content) and male gender (p<0.05). In HCV-RNA negative subjects, the median total iron score was 27 (range, 0-52). Iron accumulated in both mesenchymal cells and hepatocytes, and the presence of a lobular gradient was interpreted to indicate intestinal hyperabsorption. INTERPRETATION AND CONCLUSIONS: Transfusion-dependent thalassemics have mild liver necroinflammation, mainly attributable to HCV infection. Significant fibrosis is frequent, and its progression is mostly influenced by iron overload which, with current therapy regimens, may be attributable to both erythrocyte catabolism and iron hyperabsorption.

Adult↗