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L Lazzari

Publications and source records attributed to L Lazzari.

29 records · Page 2Linked to original sources
PubMed1995

Comparative study of different procedures for the collection and banking of umbilical cord blood.

Different procedures for umbilical cord blood (CB) collection, separation, and cryopreservation were compared to evaluate the feasibility of large-scale CB banking for unrelated transplant. CB collection using an open system was associated with a 12.5% rate of bacterial contamination, whereas this rate fell to 3.3% using a closed collection system. When the umbilical cord was clamped within 30 s after delivery, on 378 occasions it was possible to collect 77 +/- 23 ml of CB without risk to mother or infant. Considering that engraftment can be obtained in recipients of 20 x 10(3) CFU-GM/kg, 86% and 28% of CB samples with a volume larger than 50 ml were found to contain a sufficient number of CFU-GM to engraft patients of 20 and 70 kg, respectively. Both Ficoll and gelatin purification procedures were associated with a recovery of 86-92% of CFU-GM, BFU-E, CFU-GEMM, and HPP-CFC, but the gelatin method appears to be more suitable for large-scale CB banking in vials. After cryopreservation, the recovery of clonogenic progenitors was similar for both CB samples stored as whole blood or as mononuclear cells separated using Ficoll or gelatin. In conclusion, large-scale CB banking seems feasible, and CB cell separation could allow storage of a large number of CB samples in a limited liquid nitrogen space.

Blood Banks↗
PubMed1995

The effect of interleukin-12 in ex-vivo expansion of human haemopoietic progenitors.

We evaluated progenitor cell proliferation in cultures supplemented by different cytokine combinations in the presence or absence of IL-12. In cultures of low density cells, cytokine combinations including IL-12 were associated to a greater proliferation (up to 6.7 +/- 2.5 CFU-GM fold expansion). However, in cultures of purified CD34+ cells the more efficient cytokine combination (147 +/- 49 CFU-GM fold expansion) was SCF, IL-3, IL-11 and MIP-1 alpha, and the addition of IL-12 did not further enhance expansion of progenitors. These results indicate that accessory cells, lost in CD34+ cell purification, could be in part responsible for IL-12 effect on progenitor cell proliferation. In CD34+ cell cultures the addition of IL-12 led to CD19 mRNA generation, suggesting that IL-12 acts on haemopoietic cells with both myeloid and lymphoid potential.

Antigens, CD↗
PubMed1994

Retrovirus-mediated transfer of the multidrug resistance gene into human haemopoietic progenitor cells.

We report the utilization of cord blood (CB) or bone marrow (BM) derived low density or purified CD34+ cells as a target for human multidrug resistance (MDR1) gene transfer. Cells were cocultivated for 48 h with an irradiated MDR1 retroviral producer line. Since some degree of MDR1 gene expression has been reported to occur in haemopoietic progenitor cells and in peripheral blood cells, efficiency of MDR1 gene transfer was assessed by: (1) Drug selection and culture in presence of 50 ng/ml doxorubicin, 10 ng/ml colchicine and 0.85 micrograms/ml taxol. In uninfected control, 1-2% of CFU-GM and CFU-GEMM were found to be drug-resistant, while 14-31% of original clonogenic activity was found after 2 weeks of culture of transduced cells. Efficiency of MDR1 transfer was significantly enhanced by prestimulation with cytokines, and found to be significantly superior in CB-derived compared to BM-derived progenitors. (2) Analysis of MDR1 gene expression by evaluating MDR1 mRNA through polymerase chain reaction. MDR1 expression was very low in cultures of uninfected controls, whereas, after drug selection, MDR1 mRNA levels in transduced cells was as high as in the MDR1 retroviral producer line (positive controls). (3) Flow cytometric analysis of the expression of CD34 and P-glycoprotein, the product of the MDR1 gene. After MDR1 transduction and 2 weeks of culture, membrane expression of P-glycoprotein was found on 17-25% of viable CD34+ cells. (4) Cytochemical localization by APAAP staining of P-glycoprotein. No specific localization was found in untransduced controls, whereas transduced and cultured CB-cells expressed P-glycoprotein on plasma and nuclei membrane. In conclusion, MDR1 gene transfer into CB- and BM-derived progenitor cells seems a feasible and attractive approach to generate a drug-resistant haemopoiesis.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Cord blood plasma-mediated ex vivo expansion of hematopoietic progenitor cells.

Cord blood (CB) plasma has previously been found to augment the replating capacity of CB-derived hematopoietic progenitors. In the present study, we observed a 2.8 +/- 0.3 and a 1.8 +/- 0.2-fold expansion of CFU-GM in cultures of CB cells without growth factors but supplemented by CB plasma or maternal blood (MB) plasma, respectively. In the absence of growth factors, CFU-GM expansion did not occur in CB cell cultures supplemented with fetal calf serum (FCS), peripheral blood (PB) plasma, PB plasma plus concentrations of IL-6 similar to those previously reported in CB plasma and in bone marrow (BM) cell cultures supplemented with FCS, CB, MB or PB plasma. In the presence of stem cell factor (SCF), IL-3 and IL-11, an expansion of CFU-GM was observed in CB and BM cell cultures supplemented by either CB, MB or PB plasma or FCS. Nevertheless, progenitor expansion was significantly superior in CB cell cultures supplemented by CB plasma (8.7 +/- 0.7, 2.4 +/- 0.3 and 2.6 +/- 0.3-fold expansions for CFU-GM, BFU-E and CFU-Mix, respectively). In conclusion, an unknown factor(s) present in CB plasma, probably capable of crossing the placenta, has an effect alone and in the presence of growth factors in supporting ex vivo expansion of CB progenitors.

Adult↗
PubMed1993

Cord blood banking for stem cell transplant.

Umbilical cord blood has been recently used as a source of hematopoietic progenitor cells for transplantation of pediatric patients. This study was performed to evaluate the feasibility of a cord blood bank for unrelated transplant. When the umbilical cord was clamped within 20 seconds after delivery, it was possible to collect 86 +/- 25 ml of cord recipients with more than 2000 CFU-GM/kg; 53% of cord blood samples were found to contain enough CFU-GM for engraftment in 50-70 kg adult patients.

Adult↗
PubMed1976

[Evaluation of the relations between serum proteins electrophoresis and other laboratory tests in monoclonal gammopathies (author's transl)].

We have considered interesting to determine monoclonal gammopathies incidence, in 2191 serum proteins electrophoresis performed in our laboratory from January to December 1974. We have found 15 cases of monoclonal gammopathies, some cases combined with Mieloma (3 cases), some other with other with non specific diseases. We have considered the relations between type of gammopathy and other laboratory tests useful for any other diagnose: they are: immunochemical analysis, E.S.R., red and white count, total proteins, Bence Jones protein.

Bence Jones Protein↗
PubMedDate not supplied

Sentinel node biopsy in breast cancer: the experience of Brescia Civic Hospital.

The accuracy of the sentinel node technique in the evaluation of axillary node involvement in breast cancer was evaluated in 83 consecutive patients with monofocal T1-2 carcinoma, who were clinically N0 and who underwent lymphoscintigraphy with 99mTc-colloid integrated with intraoperative sentinel node detection by a portable probe. Lymphoscintigraphy revealed at least one sentinel node in 75 patients (90.4%), always identified by the probe. In eight patients (9.6%) the sentinel node was detected neither by lymphoscintigraphy nor by the probe. All removed lymph nodes were analyzed by hematoxylin-eosin histology and the sentinel node by immunostaining. In 28/75 patients (37.3%) at least one metastatic axillary lymph node was detected; in 16 of the 28 N+ subjects (57%) only the sentinel node was positive. The false negative rate (sentinel node negative/other axillary lymph nodes positive) was 17.85% (5/28 patients). In 9/23 patients (39%) micrometastases were found in the sentinel node only. In conclusion, specific sentinel node positivity in 57% of cases supports the validity of the sentinel node concept. Moreover, nine patients would have been considered N0 by standard hematoxylin-eosin histology without sentinel node-aided immunostaining. A 17.8% false negative rate calls for caution in patients with negative sentinel nodes.

Adult↗
PubMedDate not supplied

[The role of intraoperative parathyroid hormone assay in the surgical management of hyperparathyroidism].

Surgical management of primary hyperparathyroidism has undergone several chances in recent years and historically has required bilateral neck exploration with identification of the parathyroid adenoma together with three normal glands. The intraoperative hormone assay allows a more limited procedure by confirming complete removal of hypersecreting tissue. The Authors report surgical treatment of 24 consecutive hyperparathyroidism and conclude that evaluation of intraoperative hormone assay accurately predicts the determination of adequacy of resection and the correct outcome of surgery in patients with parathyroid adenomas.

Adenoma↗