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1.
Environ Pollut ; 231(Pt 1): 237-251, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28802993

RESUMO

Gentle remediation options (GRO) are based on the combined use of plants, associated microorganisms and soil amendments, which can potentially restore soil functions and quality. We studied the effects of three GRO (aided-phytostabilisation, in situ stabilisation and phytoexclusion, and aided-phytoextraction) on the soil microbial biomass and respiration, the activities of hydrolase enzymes involved in the biogeochemical cycles of C, N, P, and S, and bacterial community structure of trace element contaminated soils (TECS) from six field trials across Europe. Community structure was studied using denaturing gradient gel electrophoresis (DGGE) fingerprinting of Bacteria, α- and ß-Proteobacteria, Actinobacteria and Streptomycetaceae, and sequencing of DGGE bands characteristic of specific treatments. The number of copies of genes involved in ammonia oxidation and denitrification were determined by qPCR. Phytomanagement increased soil microbial biomass at three sites and respiration at the Biogeco site (France). Enzyme activities were consistently higher in treated soils compared to untreated soils at the Biogeco site. At this site, microbial biomass increased from 696 to 2352 mg ATP kg-1 soil, respiration increased from 7.4 to 40.1 mg C-CO2 kg-1 soil d-1, and enzyme activities were 2-11-fold higher in treated soils compared to untreated soil. Phytomanagement induced shifts in the bacterial community structure at both, the total community and functional group levels, and generally increased the number of copies of genes involved in the N cycle (nirK, nirS, nosZ, and amoA). The influence of the main soil physico-chemical properties and trace element availability were assessed and eventual site-specific effects elucidated. Overall, our results demonstrate that phytomanagement of TECS influences soil biological activity in the long term.


Assuntos
Biodegradação Ambiental , Microbiologia do Solo , Poluentes do Solo/análise , Oligoelementos/análise , Bactérias/efeitos dos fármacos , Betaproteobacteria , Biomassa , Eletroforese em Gel de Gradiente Desnaturante , Europa (Continente) , França , Plantas , Solo/química , Poluentes do Solo/toxicidade , Oligoelementos/toxicidade
2.
J Environ Manage ; 129: 283-91, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23973957

RESUMO

Gentle Remediation Options (GRO) are risk management strategies or techniques for contaminated sites that result in no gross reduction in soil functionality (or a net gain) as well as risk management. Intelligently applied GROs can provide: (a) rapid risk management via pathway control, through containment and stabilisation, coupled with a longer term removal or immobilisation/isolation of the contaminant source term; and (b) a range of additional economic (e.g. biomass generation), social (e.g. leisure and recreation) and environmental (e.g. CO2 sequestration) benefits. In order for these benefits to be optimised or indeed realised, effective stakeholder engagement is required. This paper reviews current sector practice in stakeholder engagement and its importance when implementing GRO and other remediation options. From this, knowledge gaps are identified, and strategies to promote more effective stakeholder engagement during GRO application are outlined. Further work is required on integrating stakeholder engagement strategies into decision support systems and tools for GRO (to raise the profile of the benefits of effective stakeholder engagement and participation, particularly with sector professionals), and developing criteria for the identification of different stakeholder profiles/categories. Demonstrator sites can make a significant contribution to stakeholder engagement via providing evidence on the effectiveness of GRO under varying site contexts and conditions. Effective and sustained engagement strategies however will be required to ensure that site risk is effectively managed over the longer-term, and that full potential benefits of GRO (e.g. CO2 sequestration, economic returns from biomass generation and "leverage" of marginal land, amenity and educational value, ecosystem services) are realised and communicated to stakeholders.


Assuntos
Conservação dos Recursos Naturais/métodos , Tomada de Decisões , Recuperação e Remediação Ambiental/métodos , Biodegradação Ambiental , União Europeia , Medição de Risco , Solo
3.
Bone Marrow Transplant ; 27(8): 777-83, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11477433

RESUMO

We performed HLA-mismatched stem cell transplantation with megadoses of purified positively selected mobilized peripheral blood CD34(+) progenitor cells (PBPC) from related adult donors in 39 children lacking an otherwise suitable donor. The patients received a mean number of 20.7 +/- 9.8 x 10(6)/kg purified CD34(+) and a mean number of 15.5 +/- 20.4 x 10(3)/kg CD3(+) T lymphocytes. The first seven patients received short term (<4 weeks) GVHD prophylaxis with cyclosporin A, whereas in all the following 32 patients no GVHD prophylaxis was used. In 38 evaluable patients, five patients experienced primary acute GVHD grade I and one patient grade II. In 32 patients, no signs of primary GVHD were seen and GVHD only occurred after T cell add backs. T cell reconstitution was more rapid if the number of transplanted CD34(+) cells exceeded 20 x 10(6)/kg. Of the 39 patients, 15 are alive and well, 13 died due to relapse and 10 transplant-related deaths occurred. We conclude that the HLA barrier can be overcome by transplantation of megadoses of highly purified mismatched CD34(+) stem cells. GVHD can be prevented without pharmacological immunosuppression by the efficient T cell depletion associated with the CD34(+) positive selection procedure. This approach offers a promising therapeutic option for every child without an otherwise suitable donor.


Assuntos
Antígenos CD34/sangue , Transplante de Células-Tronco Hematopoéticas/métodos , Histocompatibilidade , Adolescente , Doadores de Sangue , Criança , Pré-Escolar , Feminino , Doença Enxerto-Hospedeiro/prevenção & controle , Hematopoese , Teste de Histocompatibilidade , Humanos , Lactente , Depleção Linfocítica , Masculino , Pais , Análise de Sobrevida , Linfócitos T/imunologia , Transplante Homólogo/imunologia , Transplante Homólogo/métodos , Resultado do Tratamento
4.
Biol Neonate ; 77(3): 168-73, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10729720

RESUMO

Granulocyte colony-stimulating factor (G-CSF) promotes neutrophil production and enhances neutrophil function. The effects of G-CSF are mediated by binding to its receptor. Since neutrophils are an essential part of the neonatal host defense system, we studied G-CSF receptor expression in neonatal neutrophils. We determined protein and mRNA expression of G-CSF receptor in freshly isolated neutrophils from cord blood of healthy term newborns (n = 16) and of adults (n = 6) as well as the in vitro effect of supplemented recombinant human G-CSF (rhG-CSF) and tumor necrosis factor-alpha (TNF-alpha) on G-CSF receptor expression of neutrophils. Expression of G-CSF receptor on the surface of neutrophils of cord blood was significantly lower compared to adults (61 +/- 6 vs. 89 +/- 2%). G-CSF receptor mRNA transcripts of neutrophils from newborns compared to adults was lower, too (77 +/- 14 vs. 152 +/- 33%). Neutrophils isolated from cord blood showed a decrease of G-CSF receptor expression within 24 h of culture. Moreover, we were able to show that supplemented rhG-CSF is necessary for maintenance of G-CSF receptor expression. TNF-alpha, however, down-regulated G-CSF receptor expression. We conclude that low protein and mRNA expression of G-CSF receptor in neutrophils of neonates compared to adults may adversely affect granulopoiesis and neutrophil functions by decreased responsiveness to G-CSF. Furthermore, G-CSF receptor expression on neutrophils was modified not only by G-CSF itself, but also by TNF-alpha.


Assuntos
Sangue Fetal/citologia , Neutrófilos/metabolismo , RNA Mensageiro/sangue , Receptores de Fator Estimulador de Colônias de Granulócitos/genética , Adulto , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Recém-Nascido , Neutrófilos/efeitos dos fármacos , Receptores de Fator Estimulador de Colônias de Granulócitos/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
5.
Acta Anaesthesiol Sin ; 37(3): 147-50, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10609348

RESUMO

Injury of the cervical spine may cause serious complications and neurological sequelae. Recently, a patient with C1-2 spinal cord compression developed pulmonary edema postoperatively associated with unstable hemodynamics, which might result from overzealous fluid administration in order to correct neurogenic shock during anesthesia. Therefore, early recognition and timely use of vasoconstrictors, together with judicious fluid replacement are important in the anesthetic management of patients with cervical spine injury undergoing surgery. In addition, the placement of pulmonary artery catheter is crucial for assessing the cardiac function and fluid status.


Assuntos
Vértebras Cervicais/cirurgia , Complicações Pós-Operatórias/etiologia , Edema Pulmonar/etiologia , Compressão da Medula Espinal/complicações , Adulto , Humanos , Masculino
6.
Bone Marrow Transplant ; 24(6): 583-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10490722

RESUMO

We present our experience with three clinical scale isolation methods for positive selection of CD34+ progenitors from peripheral blood for autologous and allogeneic transplantation in children. A combination of the CellPro device and the Magnetic Activated Cell Sorting system (MACS), as well as two different combinations of MACS systems were used (VarioMACS-SuperMACS and SuperMACS-SuperMACS). With the CellPro-MACS combination (16 separations), a median purity of 96.2% and a median recovery of 42% CD34+ cells could be achieved, whereas the two step MACS systems (55 and 29 separations) showed a median purity of 97.6% and 98.0% and a median recovery of 96.5% and 97%, respectively. Depletion of T cells was profound (4-5 log). A total of 34 patients in the autologous and 18 patients in the allogeneic setting have been transplanted with highly enriched CD34+ cells, obtained by these methods. Only one patient failed to engraft, all other patients showed a rapid and sustained hematological engraftment with the longest follow-up of 3 years. In summary, especially the two step MACS systems have proven to be appropriate tools for enrichment of CD34+ cells, yielding both high purity and good recovery, and can thus be used for tumor cell purging in the autologous setting and for effective T cell depletion in the allogeneic setting.


Assuntos
Antígenos CD34/análise , Transplante de Células-Tronco Hematopoéticas , Separação Imunomagnética , Adolescente , Adulto , Sobrevivência Celular , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade , Transplante Autólogo , Transplante Homólogo
7.
Eur J Pediatr ; 158(6): 497-500, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10378400

RESUMO

UNLABELLED: Neutrophils are an essential component of the human host defence system against infection. Recombinant human granulocyte colony-stimulating factor induces neutrophilia and enhances effector functions of mature neutrophils. Since the biological effects of granulocyte colony-stimulating factor (G-CSF) are mediated by its receptor, we investigated the expression of G-CSF receptor on the surface of neutrophils of term and preterm neonates (n = 22) with and without signs of infection and of healthy adults (n = 13) by flow cytometry. In healthy adults, the percentage of neutrophils expressing G-CSF receptor was higher compared to cord blood of term and preterm neonates (87% vs 53%, P < 0.05). Between 2 and 32 h of life, neonates with signs of infection showed lower values of G-CSF receptor expression compared to neonates without signs of infection (32% vs 54%, P < 0.05). No correlation was detectable between expression of G-CSF receptor and gestational age. CONCLUSION: Expression of granulocyte colony-stimulating factor receptor on neutrophils is lower than in adults. This may adversely affect granulopoiesis and neutrophil function during the neonatal period. Moreover, granulocyte colony-stimulating factor receptor expression seems to be down-regulated during neonatal infection.


Assuntos
Recém-Nascido/imunologia , Doenças do Prematuro/imunologia , Recém-Nascido Prematuro/imunologia , Infecções/imunologia , Neutrófilos/metabolismo , Receptores de Fator Estimulador de Colônias de Granulócitos/biossíntese , Adulto , Sangue Fetal/imunologia , Citometria de Fluxo , Humanos
8.
Horm Res ; 52(4): 192-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10725785

RESUMO

The debate about a direct or indirect effect of GH and IGF-I on the recurrence of malignancy, especially in the case of rhGH therapy in patients with leukemia, is still going on. Recent studies suggested that IGF-I plays a role in drug resistance during anticancer therapy. This resistance to diverse cytotoxic drugs, named multidrug-resistance (MDR), is mainly due to high levels of P-glycoprotein (P-gp). The gene encoding this membrane-associated transporter protein was named MDR1, and increased levels of P-gp are linked to enhanced MDR1 mRNA expression. Our aim was to investigate a possible effect of rhIGF-I on MDR1 gene expression in vitro. We cultured the T-lymphoblastoid cell line CCRF-CEM with different rhIGF-I concentrations (0, 5, 20 and 50 ng/ml) in serum-free medium for 3 days. CCRF-CEM cells are drug-sensitive and express MDR1 at low levels. MDR1 mRNA expression was measured by semiquantitative RT-PCR using a competitive assay with a heterologous DNA construct. In addition, GAPDH mRNA was amplified as an internal control for RNA integrity. P-gp activity was determined by a flow cytometric assay measuring rhodamine 123 accumulation. Furthermore, cell proliferation was monitored in all experiments. Our data do not support an effect of rhIGF-I on MDR1 mRNA expression, P-gp activity or cell proliferation in the CCRF-CEM cell line. MDR1 mRNA levels were inversely correlated to cell density with high significance (p < 0.0001). In conclusion, multidrug resistance linked to P-gp is not induced by IGF-I in CCRF-CEM cells. At high density, CCRF-CEM cells downregulate MDR1 gene expression. Our experimental model provides a very useful tool for monitoring the influence of growth factors on multidrug resistance in vitro.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Contagem de Células , Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Leucemia-Linfoma de Células T do Adulto/metabolismo , Humanos , RNA Mensageiro/análise , Receptor IGF Tipo 1/genética , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
9.
Acta Anaesthesiol Sin ; 37(4): 215-20, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10670121

RESUMO

Perioperative pulmonary thromboembolism can proceed rapidly with grave prognosis, in which immediate or accurate diagnosis and management is not easy. According to the literatures, patients receiving spinal surgery are at relatively lower risk of developing thromboembolism. We would like to present a case of postoperative pulmonary thromboembolism which developed after a prolonged lumbar spinal surgery. Tachycardia and unstable hemodynamics were noted postoperatively. Pulmonary and right atrial thrombi were disclosed by transesophageal echocardiography. Although cardiotomy and thrombectomy were immediately performed, the patient finally died 3 days after the operation. The pathogenesis of venous thromboembolism (VTE) in the surgical patients, the risk factors which predispose a patient to VTE, diagnosis, and treatment as well as the prophylactic measures of VTE are herein reviewed and discussed.


Assuntos
Trombose Coronária/etiologia , Complicações Pós-Operatórias/etiologia , Embolia Pulmonar/etiologia , Coluna Vertebral/cirurgia , Trombose Venosa/etiologia , Idoso , Feminino , Humanos
10.
Leuk Res ; 22(4): 355-63, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9669840

RESUMO

In this report we evaluated the exact expression pattern of c-Kit on mobilized peripheral blood (PB) CD34+ cells. Using a monoclonal antibody against CD117 antigen (95C3), flow cytometric analysis revealed that approximately 25% of the mobilized PB CD34+ cells coexpress c-Kit. This cell fraction showed a considerable heterogeneity with respect to c-Kit expression, consisting of a small fraction with high levels of c-Kit (4.2%) (CD34+/CD117high fraction) and a larger proportion of cells expressing low levels of this antigen (21.0%) (CD34+/CD117low fraction). Clonogenic assays showed that CD34+/CD117high cell fraction consisted almost exclusively of erythroid progenitors, in contrast to CD34+/CD117low cell subset which gave rise mostly to granulocyte-monocyte colonies. The majority of CFU-GEMM and the most primitive week 6 cobblestone area forming cells (CAFCs) segregated in the CD34+/CD117low cell subset, suggesting the highest content of multipotential progenitors within this cell fraction. None of the sorted cell subsets was able to produce reactive oxygen intermediates (ROI). However, ex vivo expansion of the sorted subsets with interleukin 3, stem cell factor and FLT3 ligand for 2 weeks resulted in a significant production of O2- and H2O2/HOCl by CD34+/CD117low cell fraction, compared to the same sorted but not expanded counterparts. According to the major content of multipotential hematopoietic progenitors and highest capacity to generate sufficient amounts of ROI after ex vivo expansion, we suggest that CD34+/CD117low cell subset would be one of the most potential candidates for transplantation in patients with acute lymphoblastic leukemia, which lack c-Kit antigen expression.


Assuntos
Antígenos CD34/análise , Mobilização de Células-Tronco Hematopoéticas , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/fisiologia , Proteínas Proto-Oncogênicas c-kit/biossíntese , Antígenos CD7/análise , Antígenos CD2/análise , Separação Celular , Ensaio de Unidades Formadoras de Colônias , Citometria de Fluxo , Humanos , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
11.
Pediatr Res ; 44(1): 32-6, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9667367

RESUMO

We have previously shown that Curosurf, a natural porcine surfactant, and its phospholipids effectively suppressed secretion of tumor necrosis factor (TNF-alpha) by resting and through lipopolysaccharide (LPS)-stimulated human monocytes. In this study the effect of Curosurf on monocyte mRNA for TNF-alpha and TNF-alpha type II-receptor (TNF-alpha-RII) were analyzed to evaluate the cellular mechanisms involved in the modulation of TNF-alpha expression. LPS-stimulated monocytes simultaneously exposed to Curosurf (500 microg/mL for 24 h) expressed approximately 70% less TNF-alpha mRNA when compared with control subjects (p < 0.05). In addition, 86% less TNF-alpha RII mRNA was found in monocytes exposed to Curosurf (p < 0.001). Decreased mRNA expression was clearly associated with significantly reduced secretion of TNF-alpha protein (Curosurf-exposed LPS-stimulated monocytes 3628 +/- 1873 pg/mL TNF, LPS-stimulated monocytes 31,376 +/- 2524 pg/mL TNF; mean +/- SEM, p < 0.001). The activation of the transcription factor nuclear factor-kappaB upon LPS stimulation is not affected by Curosurf incubation. This excludes that the decrease in mRNA and protein levels of TNF-alpha and TNF-alpha-RII is due to an inhibition of nuclear factor-kappaB activation by Curosurf. We conclude that Curosurf affects TNF-alpha release of LPS-stimulated monocytes at a pretranslational site by down-regulating both mRNA for TNF-alpha and TNF-alpha-RII, therefore acting as an anti-inflammatory agent within alveolar space.


Assuntos
Produtos Biológicos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Monócitos/imunologia , Fosfolipídeos , Surfactantes Pulmonares/farmacologia , Receptores do Fator de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Animais , Núcleo Celular/fisiologia , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Humanos , Monócitos/efeitos dos fármacos , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Receptores do Fator de Necrose Tumoral/biossíntese , Suínos , Fator de Necrose Tumoral alfa/biossíntese
12.
Bone Marrow Transplant ; 21(10): 987-93, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9632271

RESUMO

Peripheral stem cells were mobilized and collected in 26 pediatric patients with malignant diseases. A total of 47 leukaphereses were performed in the 26 patients. The mean number of nucleated cells collected was 4.5 +/- 2.6 x 10(8)/kg and the number of CD34+ progenitors collected was 6.7 +/- 6.8 x 10(6)/kg. CD34-positive selection was performed using a two-step method of magnetic-activated cell sorting (MACS) in 24 patients or a combination of an immunoaffinity column and MACS in two patients. The purity of the positively selected CD34+ progenitors was 98.8 +/- 0.7% and the number of isolated CD34+ cells was 6.5 +/- 5.9 x 10(6)/kg. Thus, the mean recovery of CD34+ cells was 93 +/- 10%. In 22 of the 26 patients, high-dose chemotherapy was performed with subsequent reinfusion of the highly purified CD34+ cells. In all 22 patients, a normal hematopoietic reconstitution was seen with a mean time of 12.4 +/- 2.7 days to reach >0.5 x 10(9)/l neutrophils (range 8-19 days). The time to reach independence from platelet transfusion was 31.6 +/- 17.0 days (range 16-78 days). There were no transplant-related deaths. In summary, we have shown that mobilized peripheral CD34+ progenitors can be highly purified with a good recovery, and that reinfusion of these cells after high-dose chemotherapy results in a rapid, complete and sustained engraftment. We conclude that this method can be used for purging in any CD34-negative malignancies and for autologous T and B cell depletion in the treatment of autoimmune diseases with high-dose immunoablative therapy.


Assuntos
Antígenos CD34/análise , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Separação Imunomagnética , Adolescente , Contagem de Células , Criança , Pré-Escolar , Citometria de Fluxo , Hematopoese , Humanos , Lactente
13.
Leuk Res ; 21(10): 933-40, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9403004

RESUMO

Multi drug resistance (MDR) is often due to an increased efflux of anti cancer drugs out of leukemic blast cells. Efflux assays are used to get an impression of functional resistance in those cells. Dyes like rhodamine 123 or 3'3'-diethyloxocarbocyanine iodide are commonly used for this purpose. A major known disadvantage is that dyes do not behave like cytotoxic drugs in efflux experiments. Assays using the self fluorescence of drugs like anthracyclines can not reveal a real impression of intracellular or effluxed drug due to quenching of the drug fluorescence in the nuclei of the cells. We have developed a reproducible and sensitive assay for direct and quantitative determination of drug efflux out of blast cells. This was done by a novel double radioactive labelling using a 3H-labelled drug and 14C-labelled sucrose as extracellular marker. So this assay can be applied to every drug of interest. Quenching of fluorescence is also by-passed with this technique as well as protracting washing or silicon oil procedures. As a model system we used the T-lymphoblastoid cell line CCRF CEM and its resistant sublines vincristine 100 and adriamycin 5000. The results were also transferable to clinical specimens of leukemic patients. In conclusion our assay may be used for precise and direct efflux measurement of a broad range of anti-cancer drugs in clinical MDR evaluation.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Fluorescência , Leucemia Mieloide/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistência a Múltiplos Medicamentos , Feminino , Citometria de Fluxo , Corantes Fluorescentes , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mielomonocítica Aguda/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , RNA Mensageiro/análise , Rodamina 123 , Rodaminas , Células Tumorais Cultivadas
14.
Bone Marrow Transplant ; 20(7): 593-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9337062

RESUMO

CD34-positive cells were isolated from cord blood (n = 8), bone marrow (n = 4) and leukapheresed material (n = 7), using an immunomagnetic isolation technique, MACS (Miltenyi Biotec, Bergisch Gladbach, Germany). In flow cytometric analysis, cell populations after enrichment revealed a fraction of 96.1% (cord blood), 96.2% (bone marrow) and 98.6% (leukapheresis material) CD34-positive cells. Cells were further stained with antibodies specific for CD44 isoforms: CD44s (SFF-2), CD44v5 (VFF-8) and CD44v6 (VFF-18). CD44-positive cells were detected by directly (FITC, fluorescein isothiocyanate) or indirectly (streptavidin-PE, phycoerythrin)-conjugated fluorochromes in flow cytometric analysis. Analysis was restricted to CD34-positive cells. A high expression of CD44s was noted in all kinds of material under investigation with mean values in the range of 98.6-100%. There was little expression of CD44v6 (mean values in the range of 1.5-3.6%) and very slight expression of CD44v5 (mean values in the range of 0.6-1.4%). The finding that CD34-positive hematopoietic stem cells express CD44v5 and CD44v6 to a very small extent offers the possibility of using antibodies specific to CD44v5 and CD44v6 in immunopurging in the course of autologous stem cell transplantation.


Assuntos
Células da Medula Óssea/imunologia , Sangue Fetal/imunologia , Receptores de Hialuronatos/biossíntese , Leucaférese , Adulto , Antígenos CD34/imunologia , Células da Medula Óssea/citologia , Feminino , Sangue Fetal/citologia , Citometria de Fluxo , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Humanos , Receptores de Hialuronatos/imunologia , Imunofenotipagem , Gravidez
15.
Blood ; 90(1): 111-25, 1997 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9207445

RESUMO

The class III receptor tyrosine kinase FLT3/FLK2 (FLT3; CD135) represents an important molecule involved in early steps of hematopoiesis. Here we compare cell-surface expression of FLT3 on bone marrow (BM) and cord blood (CB) cells using monoclonal antibodies (MoAbs) specific for the extracellular domain of human FLT3. Flow cytometric analysis of MACS-purified BM and CB cells showed that 63% to 82% of BM CD34+ and 88% to 95% of the CB CD34+ cells coexpress FLT3. Clonogenic assays and morphological characterization of FACS-sorted BM CD34+ cells demonstrate that colony-forming unit-granulocyte-macrophage (CFU-GM) and immature myelo-monocytic precursor cells are enriched in the subpopulation staining most brightly with the FLT3 MoAb whereas the majority of the burst-forming units-erythroid (BTU-E) and small cells with lymphoid morphology are found in the FLT3- population. In contrast, statistically indistinguishable proportions of CFU-granulocyte-erythrocyte-megakaryocyte-macrophage (CFU-GEMM) and more primitive cobblestone area forming cells (CAFC) were detected in both fractions, albeit the FLT3+ fraction consistently showed more CAFC activity than the FLT3- fraction. Although in both, BM and CB the majority of CD34+CD117+ (KIT+), CD34+CD90+ (Thy-1+), and CD34+CD109+ cells coexpress FLT3, three-color phenotypic analyses are consistent with the functional findings and suggest that the most primitive cells defined as CD34+CD38-, CD34+CD71low, CD34+HLA-DR-, CD34+CD117low, CD34+CD90+, and CD34+CD109+ express low levels of cell-surface FLT3 and were therefore not enriched to a statistically significant extent with the bright versus negative sorting scheme. Thus, clear segregation of the most primitive progenitors from BM CD34+ cells was confounded by low apparent levels of FLT3 cell-surface expression on these cells, whereas myeloid progenitors unambiguously segregated with the FLT3 brightest cells and erythroid progenitors with the FLT3 dimmest. Additional phenotypic analyses using MoAbs against progenitor/stem cell markers including the mucinlike molecule MGC-24v (CD164), the receptor tyrosine kinases TIE, FMS (CD115), and KIT (CD117) further illustrate the differences in surface antigen expression profiles of BM and CB CD34+ cells. Notably, CD115 is rarely detected on CB CD34+ cells, whereas 20% to 25% of the BM CD34+FLT3+ cells are CD115+. Furthermore, 80% to 95% of the CB CD34+CD117+ but only 60% to 75% of the BM CD34+CD117+ cells coexpress FLT3. Only a negligible amount of CD34+CD19+ are detected in CB, while in BM 20% to 30% of CD34+CD19+ presumed pro/pre-B cells coexpress FLT3. In contrast, the majority of the CD34+CD164+ and CD34+TIE+ subsets in both CB and BM coexpress FLT3. Analysis of unseparated cells showed that FLT3 expression is not restricted to CD34+ subsets. About 65% to 70% of lymphocyte-gated BM CD34-FLT3+ cells are positive for the monocytic marker CD115 whereas 25% to 30% of these cells consist of CD10 expressing B-cell precursors. Finally, CD34- monocytes in BM, CB, and PB express FLT3 whereas granulocytes are FLT3-. Our data show that detectable FLT3 appears first at low levels on the surface of primitive multilineage progenitor cells and disappears during defined stages of B-cell development, but is upregulated and maintained during monocytic maturation.


Assuntos
Células da Medula Óssea , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Proteínas Proto-Oncogênicas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Medula Óssea/metabolismo , Diferenciação Celular , Feminino , Sangue Fetal/metabolismo , Citometria de Fluxo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunofenotipagem , Recém-Nascido , Gravidez , Receptores de Superfície Celular , Tirosina Quinase 3 Semelhante a fms
16.
J Nutr ; 127(4): 630-6, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9109615

RESUMO

The aggravation of acid-induced gastric damage and its prevention by glucose, ascorbate or glutathione precursors was studied in fed and food-deprived rats. The stomachs of fed rats and those starved for 1, 3 or 5 d were vagotomized just before irrigating for 3 h with solutions containing 0-150 mmol HCI/L. Mucosal glutathione, mucus, lipid peroxides and acid back-diffusion were measured. Stomach ulcers were evaluated by morphological and histological examination. The preventive effects of glucose, ascorbate and a mixture of L-glutamine, L-glycine and L-cysteine were evaluated in the stomachs of rats that were starved for 5 d, vagotomized, then perfused for 3 h with 100 mmol HCI/L. Greater acid back-diffusion and ulcer formation, and lower glutathione and mucus levels in starved rats were dependent on the duration of starvation and luminal acidity. Increased acid back-diffusion and decreased glutathione and mucus production were negatively correlated (r < -0.80, P < 0.05) with ulcer formation. A significant enhancement in mucosal lipid peroxide concentration and serious damage of forestomach and corpus mucosal cells were observed in starved rats exposed to 100 mmol HCI/L. These ulcerogenic factors were effectively inhibited in acid-perfused stomachs of food-deprived rats by daily intraperitoneal injection of the amino acid mixture (150 mg/kg) or by an average daily consumption via drinking water of glucose (10 g) or ascorbate (1.2 g). Starvation aggravated acid-induced gastric damage and was associated with greater acid back-diffusion and oxygen radical generation, and lower mucosal glutathione and mucus production.


Assuntos
Aminoácidos/uso terapêutico , Ácido Ascórbico/uso terapêutico , Glucose/uso terapêutico , Ácido Clorídrico/efeitos adversos , Inanição , Úlcera Gástrica/etiologia , Aminoácidos/administração & dosagem , Animais , Ácido Ascórbico/administração & dosagem , Ácido Gástrico/fisiologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Glucose/administração & dosagem , Glutationa/biossíntese , Glutationa/fisiologia , Ácido Clorídrico/antagonistas & inibidores , Peróxidos Lipídicos/biossíntese , Masculino , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/prevenção & controle , Vagotomia
17.
Leuk Res ; 20(11-12): 963-71, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9009255

RESUMO

Mononuclear cells derived from cord blood were stained using the CD1 17-specific, fluorochrome-labeled monoclonal mouse antibody 95C3. Additional staining was performed using an isotype-specific rat-anti-mouse antibody, labeled with supermagnetic microparticles. Target cells were enriched by the technique of magnetic cell separation, MACS. The resulting cell population contained 96.5% (+/-1.7% S.D.) CD1 17-expressing cells (n = 12) with different levels of CD117 antigen expression. Using flow cytometry, two cell populations differing in size were found. A majority (93%) of cells with high forward scatter revealed a phenotype positive for CD117 and CD34. Isolated cells revealed a high fraction of hematopoietic progenitors (16%). The technique presented allows for an alternative approach of stem cell enrichment and might be useful in autologous transplantation of cells with hematopoietic properties.


Assuntos
Separação Celular/métodos , Citometria de Fluxo , Células-Tronco Hematopoéticas/classificação , Separação Imunomagnética , Proteínas Proto-Oncogênicas c-kit/análise , Antígenos CD34 , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/química , Humanos , Imunofenotipagem , Recém-Nascido , Coloração e Rotulagem
18.
Nat Immun ; 15(5): 227-33, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9390271

RESUMO

A new method for the isolation of CD56+ lymphocytes from peripheral mononuclear blood cells is described. Magnetic microbeads conjugated to goat antimouse antiserum in combination with a murine monoclonal anti-CD56 antibody were coated to the CD56+ target cells. CD56+ cells were then isolated with the use of a magnetic cell sorter. The purity of the CD56+ cells was 98.4 +/- 1% (n = 12) with a recovery of the CD56+ lymphocytes of 57.2 +/- 9% (range 48-77%). The natural killer, activity of the CD56+ lymphocytes as well as the interleukin-2-induced proliferative response were not affected by the isolation procedure or the presence of the magnetic microbeads on the CD56+ cells. The described method might be a useful tool for the further characterization of CD56+ cells and their subsets and can easily be upgraded for clinical use in adoptive immunotherapy with CD56+ lymphocytes.


Assuntos
Antígeno CD56/análise , Separação Imunomagnética/métodos , Subpopulações de Linfócitos/química , Adulto , Animais , Anticorpos Monoclonais/imunologia , Antígeno CD56/imunologia , Divisão Celular , Citotoxicidade Imunológica , Cabras , Humanos , Ativação Linfocitária , Camundongos
19.
Chin J Physiol ; 38(4): 211-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8925673

RESUMO

The aim is to study the protective effects of topical sucralfate and geraniin on acidified ethanol (EtOH dissolved in 100 mM HCI plus 54 mM NaCl)-induced gastric acid back-diffusion, mucus production and mucosal ulcerations in the rat. After irrigation the stomach with acidified EtOH (10-40% v/v) for 3 hrs, a concentration-dependent increase in acid back-diffusion and in mucosal lesions, and -dependent reduction in mucus production was found. These ulcerogenic effects of EtOH were dose-relatedly inhibited by pretreatment of intragastric sucralfate (10-200 mg/kg). A high correlation (r = -0.9572) between sucralfate-induced inhibition in acid back-diffusion and -induced reduction in mucosal ulceration provoked by 30% EtOH was observed. Geraniin (10-100 mg/kg), given 30 min prior to EtOH perfusion, produced potent inhibitory effects on those ulcerogenic parameters provoked by EtOH in a dose-dependent manner. The correlation (r = -0.8638) between geraniin-induced inhibitions in acid back-diffusion and in mucosal ulceration produced by EtOH was achieved. These cytoprotective effects of sucralfate and geraniin were further confirmed by morphological and histological studies. The results suggested that the protective effects of sucralfate and geraniin on gastric mucosa against acidified EtOH-induced damage are at least partly through the inhibition in acid back-diffusion and the elevation of gastric mucus production.


Assuntos
Etanol/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Glucosídeos/farmacologia , Taninos Hidrolisáveis , Sucralfato/farmacologia , Taninos , Animais , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley
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