Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Blood Cells Mol Dis ; 35(3): 389-97, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16112591

RESUMO

Umbilical cord blood (UCB) is a source of hematopoietic progenitor cells and is used as an alternative to the bone marrow or peripheral blood for treatment of several onco-hematological diseases. Because of the limited number of CD34+ hematopoietic stem cells present in UCB units and of the elevated costs of cryopreservation, it is of paramount importance to select the UCB units that are clinically useful before storage and optimize banking efficiency by designing reliable procedures to process and freeze the selected units. Among the different parameters characterizing UCB, nucleated cell (NC) and CD34+ cell content provides useful criteria to select UCB units since clinical data documented that the infused cell load (both NC and CD34+ cells) plays an important role in the successful outcome of transplants. By evaluating volume, CD34+ cell content, NC total amount, and NC density of 117 UCB units, we found a significant association between CD34+ cell content and NC density and total amount, indicating these parameters as useful to decide UCB clinical utility. Furthermore, we set up a fast procedure to process UCB units for storage. A system for NC separation and volume reduction of UCB samples in a dedicated, germ-free, closed circuit was developed, where plasma and red blood cells (RBC) depletion was obtained by sedimentation in the presence of a 3.5% Polygeline solution. By this separation system, both RBC depletion and high NC and CD34+ cell recoveries were achieved in 60 min, and the yield was comparable to the one obtained by other separation methods. Since Polygeline has been clinically used as a plasma expander and no toxic effects on patients were reported, the protocol can be applied in the large-scale banking of UCB.


Assuntos
Bancos de Sangue , Sangue Fetal/citologia , Antígenos CD34/análise , Preservação de Sangue , Separação Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Criopreservação , Citometria de Fluxo , Células-Tronco Hematopoéticas/citologia , Humanos , Contagem de Leucócitos , Poligelina/química , Manejo de Espécimes
3.
Blood Cells Mol Dis ; 27(4): 715-24; discussion 725-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11778655

RESUMO

To obtain long-term engraftment and hematopoiesis in myeloablated patients, the cell population used for hematopoietic reconstitution should include a sufficient number of early pluripotent hematopoietic stem cells (HSCs), along with committed cells from the various lineages. For this purpose, the small subset of CD34+ cells purified from different sources must be expanded ex vivo. Since cytokines may induce both proliferation and differentiation, expansion would provide a cell population comprising committed as well as uncommitted cells. Optimization of HSC expansion methods could be obtained by a combination of cytokines able to sustain renewal of pluripotent cells yet endowed with poor differentiation potential. We used variations of the combinations of cytokines described by Brugger et al. [W. Brugger, S. Heimfels, R. J. Berenson, R. Mertelsmann, and L. Kanz (1995) N. Engl. J. Med. 333, 283-287] and Piacibello et al. [W. Piacibello, F. Sanavio, L. Garetto, A. Severino, D. Bergandi, J. Ferrario, F. Fagioli, M. Berger, and M. Aglietta (1997) Blood 89, 2644-2653] to expand UCB CD34+ cells and monitored proliferation rate and phenotype after 14 days of culture. Several hematopoietic lineage-associated surface antigens were evaluated. Our data show that flt3L and thrombopoietin in combination with IL-3, while sustaining a high CD34+ proliferation rate, provide a relatively low enrichment in very early uncommitted CD34+/CD38- cells. Conversely, in the absence of IL-3, they are less effective in inducing proliferation yet significantly increase the number of CD34+/CD38- cells. A combination of the above protocols, applied simultaneously to aliquots of the same sample, would allow expansion of both committed and pluripotent HSC. This strategy may represent a significant improvement for clinical applications.


Assuntos
Antígenos CD , Técnicas de Cultura de Células/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos CD34/análise , Antígenos de Diferenciação/análise , Diferenciação Celular , Divisão Celular/efeitos dos fármacos , Sinergismo Farmacológico , Eritropoetina/farmacologia , Sangue Fetal/citologia , Citometria de Fluxo , Células-Tronco Hematopoéticas/classificação , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Separação Imunomagnética , Imunofenotipagem , Recém-Nascido , Interleucina-3/farmacologia , Interleucina-6/farmacologia , Glicoproteínas de Membrana , Proteínas de Membrana/farmacologia , NAD+ Nucleosidase/análise , Fator de Células-Tronco/farmacologia , Trombopoetina/farmacologia
4.
Blood Cells Mol Dis ; 25(3-4): 141-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10575539

RESUMO

This study describes the multilineage differentiation pattern of purified CD34+ stem cells obtained from human umbilical cord blood. CD34+ cells were collected from 49 umbilical cord blood samples. Following immunomagnetic purification, cells were double stained with anti CD34 and CD71, CD61, CD7, CD19, CD33, CD36 and triple stained with anti CD34, CD38 and HLA-DR. Analysis were performed using a FACScan flow cytometer. After purification, the mean CD34+ cells' purity was 85.49 +/- 7.08%. Several subpopulations of umbilical cord blood CD34+ cells were identified indicating different lineage commitment. The majority of CD34+ cells expressed both CD38 and HLA-DR (91.74 +/- 3.76%), while those lacking CD38 were 3.43 +/- 2.12% (CD38-DR+) and 1.81 +/- 1.54% (CD38-DR-). These data were compared to the expression of lineage commitment markers on purified CD34+ cells from 5 mobilized peripheral blood samples. The percentage of peripheral blood CD34+CD38-DR+) and CD34+CD38-DR- cells was significantly lower than umbilical cord blood, 0.24 +/- 0.18% and 0.04 +/- 0.03% respectively. The knowledge and standardized of umbilical cord blood CD34+ cells phenotype is critical since umbilical cord blood volume is limited. The homogeneity of CD34+ subpopulation phenotype suggests that monitoring of lineage differentiation antigens may not be relevant for clinical use of umbilical cord blood samples. However, the observed higher percentage of pluripotent CD34+38- stem cells in umbilical cord blood compared to peripheral blood, that might explain the successful clinical use of umbilical cord blood even when low number of cells are used, candidates these antigens as the predictive parameter for clinical use of umbilical cord blood samples.


Assuntos
Antígenos CD34/sangue , Sangue Fetal/citologia , Antígenos CD/sangue , Antígenos CD34/imunologia , Separação Celular , Sangue Fetal/imunologia , Citometria de Fluxo , Humanos , Separação Imunomagnética/métodos , Leucaférese , Leucócitos Mononucleares/imunologia , Fenótipo , Células-Tronco/citologia , Células-Tronco/imunologia
5.
Minerva Ginecol ; 51(7-8): 277-81, 1999.
Artigo em Italiano | MEDLINE | ID: mdl-10536422

RESUMO

BACKGROUND: Hysterectomy performed totally by laparoscopy is still one of the most advanced procedure in endoscopic gynecological surgery. The aim of this study has been to evaluate the cost and the hospital charges of total laparoscopic hysterectomy as compared with those for total abdominal and vaginal hysterectomy. METHODS: In particular, as far as laparoscopic technique is concerned, the cost of linear staplers have been analyzed as compared to disposable and non-disposable instruments for bipolar coagulation. RESULTS: After analysing the data, it has been found that the use of linear staplers involves very high median costs of Lire 2,932,304 ($ 1,650) versus the use of non-disposable instruments of Lire 936,488 ($ 526). The median total hospital charges was of Lire 6,014,448 ($ 3,380) for abdominal hysterectomy, of Lire 4,449,617 ($ 2,500) for vaginal hysterectomy and of Lire 4,078,000 ($ 2,291) for laparoscopic technique with non-disposable supplies. CONCLUSIONS: The results confirm, on the one hand, that bipolar coagulation is a reliable method of hemostasis, and on the other hand that laparoscopic surgery is a technique that can be recommended as an alternative to laparotomy for hysterectomy with unquestionable benefits both for patients and hospital.


Assuntos
Histerectomia/métodos , Laparoscopia/economia , Custos e Análise de Custo , Feminino , Humanos , Histerectomia/economia , Histerectomia Vaginal , Itália
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...