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1.
Gynecol Obstet Fertil ; 38(9): 515-20, 2010 Sep.
Artículo en Francés | MEDLINE | ID: mdl-20724205

RESUMEN

Assisted Reproductive Techniques (ART) separating oocytes in sibling oocytes treated either by conventional IVF or ICSI is called mid-IVF/ICSI. We sum up here 487 attempts of this kind from six French ART centers. The mid-IVF/ICSI technique was performed in 5.6% of cases. The fertilization rate by micro-injected oocytes was significantly higher (P<0.01) than oocytes inseminated conventionally, 72.6% versus 53.4%. A failure of fertilization was observed only in mid-IVF in 21.6% of cases, which prevented a complete fertilization failure when we decided to propose to the couples concerned the mid-IVF/ICSI technique. Conversely, in 75.2% of cases, fertilization was found for the two batches of oocytes. The overall pregnancy rate has improved since the use of the mid-IVF/ICSI technique (33.1% versus 28.9%, P=0.013) and the fertilization failures decreased (10.4% versus 14.3%, P=0. 019). The pregnancy rate in only mid-IVF/ICSI cases is very high at 39.8% but for a selected population. The indications for mid-IVF/ICSI remain to be clarified especially with regard to male and idiopathic indications.


Asunto(s)
Fertilización In Vitro , Oocitos/fisiología , Inyecciones de Esperma Intracitoplasmáticas , Femenino , Francia , Humanos , Masculino , Embarazo , Índice de Embarazo
2.
Rev Med Liege ; 57(7): 443-8, 2002 Jul.
Artículo en Francés | MEDLINE | ID: mdl-12233219

RESUMEN

A 12-year old female, suffering from recurring episodes of icterus and abdominal pain, is hospitalized in emergency. She is not anemic but her hemogram reveals a high level of hyperdense red blood cells (32%; controls 0-2.5%) and an abnormal reticulocyte count (201 x 10(3)/microL; controls 29-84 x 10(3)/microL), indicating a 3.5 fold increase in RBC production. The same abnormalities are found in the patient's mother. The blood smear shows few spherocytes. RBC osmotic fragility is increased only after incubation. Hereditary spherocytosis is diagnosed following electrophoresis of membrane proteins which reveals a deficiency in band 3, a protein which links the lipid bilayer to the cytoskeleton. This case of hemolytic anemia-illustrates the physiopathologic and diagnostic significance of hyperdense RBC, which reflect the cell dehydration associated with the membrane disorder.


Asunto(s)
Eritrocitos/patología , Esferocitosis Hereditaria/diagnóstico , Esferocitosis Hereditaria/fisiopatología , Dolor Abdominal/etiología , Niño , Diagnóstico Diferencial , Femenino , Humanos , Ictericia/etiología , Proteínas de la Membrana/química , Linaje
3.
Haematologica ; 86(11): 1209-18, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11694408

RESUMEN

BACKGROUND AND OBJECTIVES: It may be useful to reduce the exposure of transplant recipients to homologous blood. This may be achieved by procuring donor-derived red blood cell (RBC) units, collecting more peripheral blood progenitor cells (PBPC) with a combination of granulocyte colony-stimulating factor (G-CSF) + recombinant human erythropoietin (rHuEpo) and by administering rHuEpo post-transplantation. DESIGN AND METHODS: Eight ABO-compatible donors were treated with rHuEpo and intravenous iron to collect 12 RBC units for use in their recipients. PBPC were collected after mobilization with rHuEpo and G-CSF in the same donors. The recipients received G-CSF and rHuEpo post-transplantation. A control group of 10 donor/recipient pairs received G-CSF alone for PBPC mobilization and after the transplantation. RESULTS: Eighty-six out of 91 planned RBC units were collected in the donors without significant decrease in hematocrit because of a 4-fold increase in RBC production despite functional iron deficiency. After 2 leukaphereses, the cumulative yields of NC and CFU-GM were lower in the study group while those of BFU-E, CFU-Mix and CD34+ cells were similar. However, erythroid recovery was significantly accelerated in the study group. INTERPRETATION AND CONCLUSIONS: Collection of 12 RBC units within 6 weeks is feasible with rHuEpo and intravenous iron; this strategy allows a dramatic reduction in recipient exposure to homologous blood; rHuEpo has no synergistic effect with G-CSF for mobilization of PBPC in normal donors and may even be deleterious; and rHuEpo in the recipient may enhance erythroid engraftment.


Asunto(s)
Citaféresis/métodos , Eritropoyetina/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Movilización de Célula Madre Hematopoyética/métodos , Adolescente , Adulto , Donantes de Sangre , Transfusión de Eritrocitos , Estudios de Factibilidad , Femenino , Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucaféresis , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Recombinantes , Trasplante Homólogo
4.
Exp Hematol ; 29(11): 1256-69, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11698121

RESUMEN

OBJECTIVE: We previously showed that the distributions of the numbers of doublings (NbD) undergone by individual megakaryocyte progenitors before commitment to polyploidization are markedly skewed and can consistently be fitted to straight lines when plotted on semilogarithmic coordinates. The slope of such lines, which yields the probability of polyploidization per doubling, is made less steep by stimulators of megakaryocyte colony formation and is less steep in mixed erythroid-megakaryocyte than in pure megakaryocyte colonies. Therefore, megakaryocytopoiesis provides a unique model for the study of clonal heterogeneity in a hemopoietic lineage, which is the subject of this review. DATA SOURCES: Articles relevant to the interpretation of these data were selected from the authors' and public databases. DATA SYNTHESIS: Exponential NbD distributions were first explained by postulating that following the assembly of thrombopoiesis-specific regulators, megakaryocyte progenitors require only a single random event to arrest proliferation and commit to polyploidization. However, this stochastic model was refuted by data indicating that intrinsic properties of individual progenitors affect the NbD they achieve. We suggest that the unequal repartition of critical compounds (including receptors, signaling molecules, and gene regulators) inherent in the stem cell-progenitor transition causes a heritable heterogeneity in megakaryocyte progenitor responsiveness to polyploidization inducers. This model would be compatible with 1) the evidence for intraclonal synchronization in megakaryocyte and other hemopoietic clones generated by committed progenitors; 2) the low probability of polyploidization of the relatively insensitive bipotent megakaryocyte progenitors; and 3) the thesis that stimulators act in part by recruiting megakaryocyte progenitor cells endowed with lesser responsiveness to polyploidization inducers and higher proliferative potential. CONCLUSION: The responsiveness of individual megakaryocyte progenitors to polyploidization inducers may be a major determinant of the exponential shape of NbD distributions.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas/citología , Megacariocitos/citología , Animales , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Senescencia Celular , Células Clonales/citología , Células Clonales/efectos de los fármacos , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/efectos de los fármacos , Variación Genética , Hematopoyesis/efectos de los fármacos , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Megacariocitos/efectos de los fármacos , Ratones , Mitógenos/farmacología , Poliploidía , Ratas , Procesos Estocásticos
5.
Acta Haematol ; 104(1): 10-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11111115

RESUMEN

A group of 100 totally or subtotally myeloperoxidase (MPO)-deficient individuals was compared to a reference population of 118 probands selected at random. Data for a protective effect of the deficiency against cardiovascular damage are presented. On the other hand, a significantly higher occurrence of severe infections and chronic inflammatory processes was noted among the deficient patients. An increased incidence of cancer among the MPO-deficient individuals was not demonstrated.


Asunto(s)
Peroxidasa/deficiencia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis/enzimología , Artritis/etiología , Enfermedades Cardiovasculares/enzimología , Enfermedades Cardiovasculares/prevención & control , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Niño , Preescolar , Enfermedad Crónica , Femenino , Humanos , Infecciones/enzimología , Infecciones/etiología , Masculino , Persona de Mediana Edad , Infarto del Miocardio/enzimología , Infarto del Miocardio/prevención & control , Neoplasias/enzimología , Neoplasias/etiología , Peroxidasa/sangre , Peroxidasa/farmacología , Factores de Riesgo
6.
Leuk Lymphoma ; 36(5-6): 485-96, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10784393

RESUMEN

Marrow dysplasia is a major characteristic of patients with myelodysplastic syndrome (MDS), along with marrow blastosis, cytopenia and cytogenetic anomalies. However, the impact of the degree of marrow dysplasia on survival has not been fully assessed. In this retrospective analysis of 111 patients selected according to the IPSS criteria of MDS diagnosis, the presence or absence of 21 dysplasia characteristics recognizable in bone marrow smears stained by the May-Grünwald-Giemsa method was correlated with patient survival. Using Cox proportional hazards regression analysis, megaloblastosis (MEGALO), neutrophil agranularity (AGRAN) and hypogranularity (HYPOGRAN) were highly significant predictors (p < 0.005), and Pelger-Huët anomaly (PELGHUET) a significant predictor (p = 0.05), of patient survival. The regression analysis yielded a dysplasia-based risk index (DI) where DI = 1.26 MEGALO + 0.82 AGRAN - 1.08 HYPOGRAN + 0.45 PELGHUET. The two subgroups of 60 and 47 patients with DI < or = 0 and > 0 showed highly significant differences in median survivals (2.6 vs 1.1 yrs; p <0.0001). Multivariate analysis further showed that DI offered additional predictive power that was independent of that provided by the IPSS (p=0.002 and 0.001 respectively). Analysis of survival curves stratified for IPSS and DI showed that the additional predictive power offered by inclusion of the DI essentially concerned the IPSS low/INT-1 risk categories. Further stratification for age did not improve survival prediction. The data indicate that a set of 4 dysplasia parameters can offer some prediction for survival of MDS patients in addition to that provided by the IPSS. Further multicenter studies should aim at including some form of evaluation of the degree of dysplasia in prognostic systems.


Asunto(s)
Médula Ósea/patología , Síndromes Mielodisplásicos/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/fisiopatología , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Supervivencia
7.
Kidney Int ; 56(3): 1113-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10469381

RESUMEN

UNLABELLED: Factors determining the percentage of hypochromic red blood cells determines iron status in hemodialysis patients. BACKGROUND: Determination of the percentage of hypochromic red blood cells (RBC; %HYPO) has been advocated as a sensitive index of functional iron deficiency during erythropoietin (EPO) therapy in hemodialyzed patients. METHODS: The significance of %HYPO in chronic renal failure was evaluated in 64 chronically hemodialyzed patients. The linear correlation was determined between %HYPO and 13 variables, including age, sex, weight, C-reactive protein (CRP), ferritin, transferrin (Tf), Tf saturation, soluble Tf receptor (sTfR), serum iron (SI), urea, parathormone, dialysis dose (Kt/V), dose of EPO administered (EPO), and absolute reticulocyte count. Multiple regression analyses were then performed to select the parameters that jointly provide the best prediction of %HYPO. RESULTS: Univariate analysis showed significant correlations between %HYPO and iron parameters (sTfR, Tf saturation, SI, and ferritin, in decreasing order), EPO, reticulocyte count, and CRP. Multivariate analysis yielded an equation showing that the variation of %HYPO is essentially associated with the combined changes in sTfR, CRP, and EPO dosage. CONCLUSIONS: %HYPO is a meaningful and inexpensive parameter that reflects the integrated effects of iron stores, inflammation, and erythropoietic stimulation on iron availability in hemodialyzed patients. Among iron exchange parameters, sTfR is the best predictor of %HYPO, followed by Tf saturation, SI, and ferritin.


Asunto(s)
Eritrocitos/metabolismo , Deficiencias de Hierro , Diálisis Renal , Adulto , Anciano , Estudios de Casos y Controles , Índices de Eritrocitos , Eritropoyetina/uso terapéutico , Femenino , Ferritinas/sangre , Hemoglobinas/metabolismo , Humanos , Hierro/administración & dosificación , Hierro/sangre , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Recuento de Reticulocitos
8.
Haematologica ; 84(4): 342-9, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10190949

RESUMEN

BACKGROUND AND OBJECTIVE: Peripheral blood progenitor cells (PBPC) are now widely used to restore hematopoiesis following high dose chemotherapy in patients with malignancies. We sought to identify parameters that could predict the yield of PBPC after mobilization with chemotherapy (CT) with or without granulocyte colony-stimulating factor (G-CSF) in cancer patients. DESIGN AND METHODS: One hundred and fifty patients underwent 627 PBPC collections during the recovery phase following CT with (n = 469) or without (n = 142) G-CSF. Hemogram, CFC-assays and CD34+ cell count were performed on peripheral blood and leukaphereses products. After log transformation of the data, differences between groups were assessed with the unpaired t-test or one-way analysis of variance. RESULTS: Seventeen and two patients required 2 and 3 mobilization cycles respectively to reach our target of 15x10(4) CFU-GM/kg. In patients with lymphoma but not in those with leukemia, the yields of both CFU-GM and CD34+ cells/kg were dramatically increased when G-CSF was added to CT for mobilization. In collections primed with CT and G-CSF, better yields were obtained in patients with breast cancer or small-cell lung carcinoma (SCLC) as opposed to other solid tumors and leukemia. Among potential predictive factors of CT- and G-CSF-primed harvests, we found that the CD34+ cell count in peripheral blood (PB) was strongly correlated with both the CFU-GM and CD34+ cell yields. Except in leukemia patients, more than 1x10(6) CD34+ cells/kg were harvested when the CD34+ cell count in blood was above 20x10(6)/L. Similarly, better results were obtained in collections performed when the percentage of myeloid progenitors in blood on the day of apheresis was above 5 % or when the leukocyte count in blood was above 5x10(9)/L. INTERPRETATION AND CONCLUSIONS: A diagnosis of breast cancer or SCLC, a leukocyte count in PB of more than 5x10(9)/L, more than 5% myeloid progenitors or more than 20x10(6) CD34+ cells/L in PB were associated with higher yields of PBPC in collections mobilized with CT+G-CSF.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Hematológicas/terapia , Movilización de Célula Madre Hematopoyética , Células Madre Hematopoyéticas/patología , Adolescente , Adulto , Anciano , Antígenos CD34 , Recuento de Células Sanguíneas , Niño , Preescolar , Terapia Combinada , Femenino , Factor Estimulante de Colonias de Granulocitos/farmacología , Neoplasias Hematológicas/patología , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucaféresis , Masculino , Persona de Mediana Edad , Neoplasias/patología , Neoplasias/terapia , Valor Predictivo de las Pruebas , Trasplante Autólogo
9.
Rev Med Liege ; 53(6): 357-62, 1998 Jun.
Artículo en Francés | MEDLINE | ID: mdl-9713217

RESUMEN

The myelodysplastic syndromes (MDS) are a heterogeneous group of disorders characterized by peripheral blood cytopenias with a hypercellular bone marrow exhibiting dyspoiesis. The predominant in elderly patients are associated with a high risk of progression to acute myelogenous leukemia. The etiology of MDS is unknown in most cases. About 10% of MDSs are secondary. MDS are classified by the French American British (FAB) classification into five subgroups. The incidence of the disorders is difficult to estimate but it seems to be increasing. Clonal cytogenetic aberrations are found in 30 to 50% of de novo MDS. The only currative treatment for MDS is allogeneic bone marrow transplantation.


Asunto(s)
Síndromes Mielodisplásicos/fisiopatología , Preleucemia/fisiopatología , Anciano , Células Sanguíneas/patología , Médula Ósea/patología , Trasplante de Médula Ósea , Aberraciones Cromosómicas/genética , Células Clonales/patología , Progresión de la Enfermedad , Humanos , Incidencia , Leucemia Mieloide Aguda/patología , Síndromes Mielodisplásicos/clasificación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/inmunología , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/terapia , Preleucemia/clasificación , Preleucemia/genética , Preleucemia/inmunología , Preleucemia/patología , Preleucemia/terapia , Pronóstico , Factores de Riesgo
10.
Bone Marrow Transplant ; 22 Suppl 1: S12, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9715872

RESUMEN

Cord blood hematopoietic progenitors undergo circadian and seasonal variations. The lowest values are obtained between 4:00 and 12:00, as well as between May and August. This represents the first observation of such rhythms before birth.


Asunto(s)
Ritmo Circadiano , Sangre Fetal , Hematopoyesis , Estaciones del Año , Bancos de Sangre , Ensayo de Unidades Formadoras de Colonias , Células Madre Hematopoyéticas/fisiología , Humanos
11.
Transfusion ; 38(2): 199-208, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9531955

RESUMEN

BACKGROUND: A study of CD34+ cell selection and transplantation was carried out with particular emphasis on characteristics of short- and long-term hematopoietic recovery. STUDY DESIGN AND METHODS: Peripheral blood stem and progenitor cells (PBPCs) were collected from 32 patients, and 17 CD34+ cell-selection procedures were carried out in 15 of the 32. One patient in whom two procedures failed to provide 1 x 10(6) CD34+ cells per kg was excluded from further analysis. After conditioning, patients received CD34+ cells (n = 10, CD34 group) or unmanipulated (n = 17, PBPC group) PBPCs containing equivalent amounts of CD34+ cells or progenitors. RESULTS: The yield of CD34+ cells was 53 percent (18-100) with a purity of 63 percent (49-82). The CD34+ fraction contained 66 percent of colony-forming units--granulocyte-macrophage (CFU-GM) and 58 percent of CFU of mixed lineages, but only 33 percent of burst-forming units-erythroid (BFU-E) (p < 0.05). Early recovery of neutrophils and reticulocytes was identical in the two groups, although a slight delay in platelet recovery may be seen with CD34+ cell selection. Late hematopoietic reconstitution, up to 1.5 years after transplant, was also similar. The two groups were thus combined for analyses of dose effects. A dose of 40 x 10(4) CFU-GM per kg ensured recovery of neutrophils to a level of 1 x 10(9) per L within 11 days, 15 x 10(4) CFU of mixed lineages per kg was associated with platelet independence within 11 days, and 100 x 10(4) BFU-E per kg predicted red cell independence within 13 days. However, a continuous effect of cell dose well beyond these thresholds was apparent, at least for neutrophil recovery. CONCLUSION: CD34+ cell selection, despite lower efficiency in collecting BFU-E, provides a suitable graft with hematopoietic capacity comparable to that of unmanipulated PBPCs. In both groups, all patients will eventually show hematopoietic recovery of all three lineages with 1 x 10(6) CD34+ cells per kg or 5 x 10(4) CFU-GM per kg, but a dose of 5 x 10(6) CD34+ cells or 40 x 10(4) CFU-GM per kg is critical to ensure rapid recovery.


Asunto(s)
Hematopoyesis , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/patología , Neoplasias/terapia , Antígenos CD34 , Diferenciación Celular , División Celular , Humanos , Trasplante Autólogo
12.
Cytometry ; 24(3): 214-25, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8800554

RESUMEN

Multiple immunophenotyping is aimed at identifying several cell populations in a single labeling procedure by their ability to bind combinations of specific labeled antibodies. The present work demonstrates the simultaneous discrimination by using image cytometry of aminomethylcoumarin acetate (AMCA), Lucifer yellow (LY), fluorescein isothiocyanate (FITC), R-phycoerythrin (PE), PE-Texas red tandem (Red613), peridinin-chlorophyll protein (PerCP), and allophycocyanin (APC), which were all bound to latex beads as streptavidin-conjugated fluorochromes. This has been the result of a step-by-step optimization of the several factors affecting the sensitivity and specificity of multiple immunofluorescence analysis. First, 14 streptavidin-conjugated fluorochromes were evaluated by using spectrofluorometry. A primary selection was then made of ten spectrally separable dyes that could be evaluated by using image cytometry. These dyes were bound to latex particles, and specific filter combinations were assembled to minimize crosstalk between fluorophores while preserving sufficient fluorescence intensity and counting statistics. Potential probe associations were then assessed by measuring the emissions of all fluorochromes that were detected by each filter combination. The resulting crosstalk matrix served as the basic tool both for final selection of the optimal filter combination and for dye set (composed, in this case, of the seven fluorochromes described above) and for mathematical correction of residual spectral overlap. Next, an image cytometry system was adapted to collect seven images of matched brightness with the selected combination of excitation/emission filters and dichroic mirrors. Finally, seven-parameter synthetic images were generated by digital image processing.


Asunto(s)
Proteínas Bacterianas/química , Colorantes Fluorescentes/química , Citometría de Imagen/métodos , Automatización , Procesamiento de Señales Asistido por Computador , Estreptavidina
13.
C R Acad Sci III ; 318(7): 779-84, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7583765

RESUMEN

Recognizable megakaryocytes are polyploid cells generated by a clonogenic, diploid progenitor, termed CFU-MKC (colony forming unit, megakaryocyte). In order to quantify polyploidization, ploidy histograms of megakaryocytes determined by microphotometric or flow cytometric measurements of megakaryocyte DNA have generally been used. However these techniques provide no information on the rate of commitment of CFU-MKC to polyploidy. Using a technique of clonal analysis determining the distributions of the number of doublings (NbD) undergone by CFU-MKC before committing to polyploidization, the polyploidization probability of CFU-MKC could be derived. This probability was found to be a constant independent from CFU-MKC mitotic history, since NbD distributions are exponential functions characterized by a constant rate of decay per doubling. By studying the effects of growth factors on polyploidization probability, it was also shown that: (1) this parameter is negatively regulated by growth factors contained in poke-weed or WEHI conditioned media, as well as by erythropoietin; (2) commitment to polyploidization does not require prior CFU-MKC division; (3) bipotent erythroid-megakaryocyte progenitors have a lower polyploidization probability than CFU-MKC; (4) determination of polyploidization probability reflects the activity of growth factors with greater accuracy than megakaryocyte colony count.


Asunto(s)
Células Madre Hematopoyéticas/citología , Megacariocitos/citología , Poliploidía , Acetilcolinesterasa/metabolismo , Animales , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Eritropoyetina/farmacología , Células Madre Hematopoyéticas/enzimología , Megacariocitos/enzimología , Ratones , Ratones Endogámicos C57BL , Probabilidad
14.
C R Acad Sci III ; 318(3): 381-6, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7788507

RESUMEN

Recognizable megakaryocytes are polyploid cells generated by a clonogenic, diploid progenitor, termed CFU-MKC (colony forming unit, megakaryocyte). In order to quantify polyploidization, ploidy histograms of megakaryocytes determined by microphotometric or flow cytometric measurements of megakaryocyte DNA have generally been used. However these techniques provide no information on the rate of commitment of CFU-MKC to polyploidy. Using a technique of clonal analysis determining the distributions of the number of doublings (NbD) undergone by CFU-MKC before committing to polyploidization, the polyploidization probability of CFU-MKC could be derived. This probability was found to be a constant independent from CFU-MKC mitotic history, since NbD distributions are exponential functions characterized by a constant rate of decay per doubling. By studying the effects of growth factors on polyploidization probability, it was also shown that: (1) this parameter is negatively regulated by growth factors contained in poke-weed or WEHI conditioned media, as well as by erythropoietin; (2) commitment to polyploidization does not require prior CFU-MKC division; (3) bipotent erythroid-megakaryocyte progenitors have a lower polyploidization probability than CFU-MKC; (4) determination of polyploidization probability reflects the activity of growth factors with greater accuracy than megakaryocyte colony count.


Asunto(s)
Células Madre Hematopoyéticas/citología , Megacariocitos/citología , Poliploidía , Acetilcolinesterasa/metabolismo , Animales , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Eritropoyetina/farmacología , Células Madre Hematopoyéticas/enzimología , Megacariocitos/enzimología , Ratones , Ratones Endogámicos C57BL , Probabilidad
15.
Invasion Metastasis ; 13(4): 201-11, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8034442

RESUMEN

A recently described personal method based on image analysis of histological sections was used in order to quantify lung colony formation by B16 melanoma cells injected intravenously into the mouse. These tumor cells were preincubated in vitro either with fibronectin (FN), laminin (LN) or fibroblasts (FB), which are implicated in the process of invasion and metastasis. Thanks to this method, a more accurate analysis of lung colonies (section area and number) formed by tumor cells was realized. By image analysis, we show that when FB were mixed with B16 cells, a drastic increase of tumor sections number and area was induced. LN increased the tumor sections area, but not their number. No effect of FN on B16 cells was observed. LN and FN promoted tumor anchorage in the depth of the lungs while FB reduced the latter. These facts could explain the contradictory results obtained by simply counting macroscopically superficial lung colonies. When cultured in vitro, these B16 melanoma cells did not produce any type of IV collagenase, either alone or in the presence of LN or FN, but in cocultures (B16 with 3T3) and in fibroblasts cultures, this enzyme was present. This could explain, among other factors, why the rate of invasiveness exerted by B16 cells is higher when the latter are coinjected with FB.


Asunto(s)
Fibronectinas/farmacología , Laminina/farmacología , Neoplasias Pulmonares/secundario , Melanoma Experimental/patología , Células 3T3 , Animales , Fibroblastos/fisiología , Gelatinasas/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias
16.
J Hematother ; 2(2): 259-61, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7921986

RESUMEN

CD34-positive cells were isolated from a total of 23 cords using CellPro Ceprate columns. AIS MicroCellector flasks, and panning. The cells were (1) expanded in serum-free culture supplemented with a variety of combinations of cytokines and (2) immunophenotyped using multiple fluorochrome labeling. The results indicated that the avidin column produced the highest purity of CD34-positive cells, and that immature blast cells could be expanded in serum-free culture. Preliminary results suggested that the four fluorochrome labeling technique may provide useful information on the lineage commitment of cord blood precursor and blast cells.


Asunto(s)
Sangre Fetal/citología , Células Madre Hematopoyéticas , Avidina , Biotina , Diferenciación Celular , División Celular/efectos de los fármacos , Separación Celular/instrumentación , Medio de Cultivo Libre de Suero , Citocinas/farmacología , Colorantes Fluorescentes , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Técnicas de Inmunoadsorción , Recién Nacido
17.
In Vivo ; 6(2): 119-24, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1381967

RESUMEN

By microscopical observation and using an original morphometric method, we analyzed on histological sections the rate of lung colony formation after the intravenous injection into the mouse of B16 melanoma cells previously cultivated in vitro as aggregates. After the injection of B16 pure spheroids, superficial lung colonies were more numerous than internal lung colonies. After the injection of mixed spheroids (B16 + 3T3 fibroblasts), the size of colony sections was increased. Addition of laminin to pure or mixed spheroids decreased the size of colony sections but increased the number of internal lung colonies.


Asunto(s)
Células 3T3/fisiología , Laminina/farmacología , Neoplasias Pulmonares/secundario , Melanoma Experimental/secundario , Animales , Comunicación Celular , División Celular , Técnicas de Cultivo/métodos , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/patología , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/patología , Ratones , Invasividad Neoplásica , Trasplante de Neoplasias , Neovascularización Patológica , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/patología , Células Tumorales Cultivadas/trasplante
18.
J Thorac Cardiovasc Surg ; 102(2): 309-17, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1650868

RESUMEN

To assess leukocyte activation during cardiopulmonary bypass, we measured white blood cell and neutrophil counts and lysosomal enzyme release, especially myeloperoxidase and elastase, throughout the operation and for 5 days postoperatively. A newly developed double antibody radioimmunoassay of myeloperoxidase and an enzyme-linked immunosorbent assay for detection of the polymorphonuclear elastase-alpha 1-proteinase inhibitor complex were used to determine their plasma levels in 15 patients undergoing elective aorta-coronary bypass grafting. Preoperatively white blood cell counts and plasmatic levels of myeloperoxidase and elastase-alpha 1-proteinase inhibitor were normal. Because no correlation has yet been established between levels of myeloperoxidase and elastase-alpha 1-proteinase inhibitor, the aim of this prospective study was to evaluate the use of these enzyme levels as markers for leukocyte activation in vivo. We addressed the clinical situation of cardiopulmonary bypass because it offered the possibility of monitoring the comparative evolution of blood levels of these enzymes in parallel to white blood cell counts through well-defined steps corresponding to known events. We document the advantages of myeloperoxidase blood levels over elastase measurement as reflecting more rapidly the in vivo activation of leukocytes. The time course kinetics of these three measurements were not parallel. White blood cell counts remained stable at the beginning of bypass, whereas myeloperoxidase levels increased sharply and continuously as soon as bypass was instituted until the end of bypass. Elastase levels also increased, but later than myeloperoxidase, beginning when the patients was rewarmed. High elastase plasma levels persisted later than myeloperoxidase after bypass, in parallel with white blood cell counts. It thus clearly appears that changes in myeloperoxidase levels more rapidly reflect the activation state of leukocytes induced by cardiopulmonary bypass and surgery, whereas peak levels of elastase were delayed and parallel to white blood cell counts. From this model, in which the evolution of leukocyte numbers could be followed in relation with known steps of stimulation, it appears that myeloperoxidase is a sensitive marker for monitoring in vivo activation of white blood cells.


Asunto(s)
Puente Cardiopulmonar , Neutrófilos/fisiología , Elastasa Pancreática/sangre , Peroxidasa/sangre , Adulto , Anciano , Biomarcadores/sangre , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neutrófilos/enzimología , Elastasa Pancreática/antagonistas & inhibidores , Estudios Prospectivos , Radioinmunoensayo , alfa 1-Antitripsina/análisis
19.
Int J Cell Cloning ; 8(4): 227-35, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1698207

RESUMEN

Methods which have been used to determine megakaryocyte ploidy in animals and humans are reviewed. Although the number of megakaryocyte nuclear units counted in bone marrow squashes is roughly proportional to ploidy, accurate determinations of DNA content require the use of microphotometry or flow cytometry. New techniques should make it possible to distinguish polyploidizing megakaryoblasts from promegakaryocytes and mature megakaryocytes which have arrested polyploidization. Only the latter should be included in histograms of the number of endoduplications, since only those have expressed their full polyploidization potential. Statistical techniques are available for analysis and comparison of both raw ploidy distributions or histograms of endoduplication numbers.


Asunto(s)
Citogenética/métodos , Megacariocitos/citología , Ploidias , Animales , Núcleo Celular , Interpretación Estadística de Datos , Citometría de Flujo , Humanos , Megacariocitos/ultraestructura , Coloración y Etiquetado
20.
Leuk Res ; 11(9): 781-7, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2823008

RESUMEN

The myeloproliferative sarcoma virus (MPSV) induces a murine myeloproliferative syndrome characterized by an erythromyelemia, an anemia, a thrombocytopenia associated with a myeloproliferation in the spleen and a splenic and medullar fibrosis. We have used the in-vitro plasma clot technique to measure megakaryocytic precursors in the spleen and bone-marrow of MPSV-infected mice. We report that megakaryocytic colonies are increased, in number (X75), in concentration (X9) and in size, in the spleen but not in the bone-marrow of neoplastic mice. Furthermore, these splenic precursors are hypersensitive to growth factors present in the anemic mouse serum used in the culture system. These data show that the thrombocytopenia observed in the MPSV-induced neoplasia does not result from a lack of megakaryocyte precursors, but rather from an excess of megakaryocyte destruction. This ineffective splenic megakaryopoiesis associated with the presence of a massive splenic fibrosis make the MPS-induced neoplasia a suitable model for studying the perturbation of megakaryopoiesis in myeloproliferative syndrome associated with fibrosis.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas/patología , Megacariocitos/fisiología , Trastornos Mieloproliferativos/patología , Bazo/patología , Animales , Médula Ósea/patología , División Celular , Ratones , Ratones Endogámicos DBA , Virus del Sarcoma Murino
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