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1.
Eur Spine J ; 27(4): 835-840, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28012079

RESUMEN

PURPOSE: To determine the significance of each parameter of the revised Tokuhashi score and identify which is associated with survival. BACKGROUND: Spinal metastases are common and can be a challenging medical issue. Treatment options depend on patients' prognosis. Many scoring systems in the literature help estimate prognosis, such as the Tokuhashi, revised Tokuhashi, and Tomita scoring systems. METHODS: A retrospective review of all patients from 2003 to 2012 treated for spinal metastases in one center was conducted. Imaging, pathology, and charts were reviewed to determine the modified Tokuhashi scores. Scores were then compared to the actual documented survival. Univariate and multiple regression analyses were used to assess the importance of each individual parameter and survival time. Linear regression was used to determine the relationship between the Tokuhashi score and weighted Tokuhashi score with survival time. RESULTS: A total of 126 patients were reviewed. All parameters in the revised Tokuhashi score were significantly associated with survival time except for primary site using univariate analysis. Only the number of spinal metastases and metastasis to major organs showed statistical significance when multiple variable analysis was used. CONCLUSION: A number of spinal metastases and metastasis to major organs were the most important predictors of actual survival. Modification to the score based on population characteristics would help better identify patients with spinal metastases that can benefit from surgery.


Asunto(s)
Índice de Severidad de la Enfermedad , Neoplasias de la Columna Vertebral/diagnóstico , Columna Vertebral/patología , Adulto , Anciano , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/mortalidad , Neoplasias de la Columna Vertebral/secundario , Tasa de Supervivencia
2.
Clin Exp Immunol ; 152(1): 50-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18241225

RESUMEN

Haematopoietic stem cell transplantation is often complicated by the life-threatening graft-versus-host disease (GVHD) which consists of an allogeneic reaction of the graft cells against the host organs. The aim of this study was to investigate the putative involvement of soluble human leucocyte antigen (sHLA) class I molecules, and particularly sHLA-G molecules, in the occurrence and/or prevention of acute GVHD (aGVHD) in allogeneic peripheral blood stem cell (PSC) transplantation. Whole sHLA class I molecules seem to be involved in aGVHD pathogenesis because detection of a high concentration of these molecules in the first month post allograft is correlated with aGVHD occurrence. Conversely, a high level of sHLA-G molecules before and after allograft could indicate good prognosis in PSC allograft transplantation. sHLA-G molecules seem to be involved in aGVHD prevention, not only because they are enriched in plasma of patients without aGVHD, but also because: (i) a positive correlation has been found between sHLA-G level and CD4+ CD25+ CD152+ natural regulatory T cell (T(reg)) frequency in the blood of transplanted patients; and (ii) the presence of CD4+ CD25+ CD152+ natural T(reg) is correlated with increased sHLA-G expression in in vitro mixed leucocyte reaction cultures. Altogether, these results support the immunomodulatory function of sHLA-G molecules that might create a regulatory network together with the natural T(reg) to foster the induction of a tolerogenic environment and improve PSC transplantation favourable outcome.


Asunto(s)
Enfermedad Injerto contra Huésped/inmunología , Antígenos HLA/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Linfocitos T Reguladores/inmunología , Biomarcadores/sangre , Estudios de Cohortes , Antígenos HLA/sangre , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/sangre , Humanos , Tolerancia Inmunológica/inmunología , Prueba de Cultivo Mixto de Linfocitos , Pronóstico , Solubilidad
3.
Leuk Res ; 32(1): 45-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17544120

RESUMEN

We report on the clinico-biological characteristics of 20 cases of gammadelta T cell large granular lymphocyte (LGL) leukemia. All the data were compared to that of 196 cases with alphabeta T cell subtype, which represents the majority of T cell LGL leukemias. Clinical findings were quite similar in the two groups regarding age, sex ratio, recurrent infections, and association with auto-immune diseases especially rheumatoid arthritis. Gammadelta LGL predominantly expressed a CD3+/CD4-/CD8+/CD16+/CD57+ phenotype, in 50% of cases. Clinical outcome was favorable for these patients with overall survival of 85% at 3 years. Fifty percent of gammadelta patients required treatment and the response to therapy was estimated at 55%. gammadelta and alphabeta T cell LGL leukemia harbor a very similar clinico-biological behavior and represent part of an antigen-driven T cell lymphoproliferation.


Asunto(s)
Leucemia de Células T/diagnóstico , Receptores de Antígenos de Linfocitos T gamma-delta , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades Autoinmunes/complicaciones , Células Clonales , Femenino , Reordenamiento Génico de la Cadena gamma de los Receptores de Antígenos de los Linfocitos T , Humanos , Inmunofenotipificación , Leucemia de Células T/inmunología , Leucopenia/diagnóstico , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T alfa-beta , Esplenomegalia/diagnóstico
4.
Leukemia ; 9(9): 1549-55, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7658724

RESUMEN

We prospectively analyzed MDR functional activity by the Rh123 efflux assay in 84 de novo acute leukemias. Thirty of the 60 AML cases (50%) showed a positive dye efflux (in more than 10% of blast cells). In 19 cases, the dye efflux was superior to 30%. Twenty-four of the 30 efflux positive cases were CD34+ and could be studied in double staining. The mean percentage of effluxing CD34+ blast cells was 54%. There was a high correlation between CD34 expression and MDR activity (P < 10(-4)), MDR activity and PgP expression (P < 10(-6)). All the efflux negative samples were PgP negative. Nine efflux positive cases were PgP negative. Five of the 24 ALL were efflux positive. MDR activity did not correlate with FAB subtype (with the exception of AML3: 1/6 was efflux positive), age, white blood cell count or LDH level. Forty-seven AML patients were treated with conventional chemotherapy including cytarabine and an anthracycline. Thirty-one (66%) entered complete remission (CR). CR rate was statistically lower for efflux positive as compared to efflux negative patients, 46 vs 87% (P = 0.003), for PgP+ as compared to PgP- patients, 40 vs 78% (P = 0.01), for CD34+ as compared to CD34- patients, 45 vs 84% (P = 0.005). There was no correlation between P110 expression (32 AML cases studied) and FAB subtype, MDR status and clinical outcome. Two years survival was 20% for efflux positive patients as compared to 54% for efflux negative patients (P < 0.07), 15% for PgP+ vs 54% for PgP- patients (P < 0.04). The finding of efflux+/PgP- cases suggests the existence of other membrane efflux pumps. Rh123 efflux assay is straightforward in routine and could be included in MDR screening because of its potential interest in clinical outcome in AML.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Resistencia a Múltiples Medicamentos , Colorantes Fluorescentes/metabolismo , Leucemia Mieloide/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Rodaminas/metabolismo , Enfermedad Aguda , Adolescente , Adulto , Anciano , Femenino , Humanos , Leucemia Mieloide/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Fenotipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Estudios Prospectivos , Inducción de Remisión , Rodamina 123
5.
Am J Med ; 102(1): 14-20, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9209196

RESUMEN

PURPOSE: The Polycythemia Vera Study Group (PVSG) has established useful criteria for the diagnosis of polycythemia vera. In some circumstances, an increase of plasma volume (PV) masks that of red cell mass (RCM), with hemoglobin (Hb) and hematocrit (Ht) remaining normal. This defines the concept of inapparent polycythemia. PATIENTS AND METHODS: One hundred and three patients seen in the hematology unit with the diagnosis of polycythemia vera were studied. There were 55 males and 48 females with a median age of 59 years. Ninety-five patients fulfilled the PVSG criteria. Spontaneous erythroid colonies and low serum erythropoietin level confirmed the diagnosis in the 8 other cases. Patients were classified according to Hb and Ht level. RESULTS: Group A consisted of 85 patients with increased Hb and Ht defined, respectively, by Hb > 18 g/dl, Ht > 0.52 in males and Hb > 16 g/dL, Ht>0.47 in females. Group B included 18 patients (17%) with inapparent polycythemia vera (IPV) defined by a normal Hb and Ht value at diagnosis. In this group, the reasons to perform RCM were as follows: splenomegaly associated with increased platelets and/or leucocytes counts (n = 8), portal vein thrombosis (n = 5), increased platelets or leucocytes counts without splenomegaly (n = 3), and isolated splenomegaly (n = 2). The two groups were balanced in terms of age, sex, leucocyte, serum iron, and platelet level. Hemoglobin and Ht levels were significantly different between the two groups. The difference between the PV was indeed highly significant. The mean PV increase was + 9.5% (nL < +20%) in group A versus + 36.3% in group B (P < 0.00005). Red cell mass was not different between the two groups. CONCLUSIONS: Increased Hb or Ht should constitute the sole criteria for RCM determination. In the context of portal vein thrombosis, isolated hyperleucocytosis, thrombocytosis, or splenomegaly, a RCM should be performed. The frequency of IPV remains to be specified but the diagnosis of polycythemia vera is probably underestimated.


Asunto(s)
Policitemia Vera/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Recuento de Eritrocitos , Femenino , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad
6.
Hum Immunol ; 59(8): 524-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9712358

RESUMEN

The class Ib HLA-G gene encodes for a molecule which is selectively expressed in fetal placental cells. Fetomaternal tolerance could be partially explained by the interactions between HLA-G molecules and KIR receptors of decidual NK cells. To determine whether the presence of HLA-G antigens might constitute a factor of immune tolerance during the tumoral process, we compared the expression of the HLA-G gene in normal and malignant hematopoietic cells. Despite a HLA-G transcriptional activity in several lymphocytes and monocytes, no antigens are found at the cell surface or in the cytosol using the specific HLA-G mAb, 87G. This lack of expression does not appear modified in malignant hematopoietic cells. However, treatment of the monohistiocytic cell line U937 with different cytokines enabled the expression of HLA-G antigens to be induced. We suggest that the potential induction of HLA-G molecules in monocytic malignant cells following secretion of cytokines may constitute a factor of immune tolerance in patients.


Asunto(s)
Expresión Génica , Genes MHC Clase I/genética , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase I/genética , Leucemia/genética , Linfoma de Células B/genética , Línea Celular Transformada/efectos de los fármacos , Citocinas/farmacología , Cartilla de ADN/química , Citometría de Flujo , Antígenos HLA/metabolismo , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Técnicas para Inmunoenzimas , Leucemia/metabolismo , Leucocitos/metabolismo , Linfoma de Células B/metabolismo
7.
Hum Immunol ; 60(7): 591-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10426276

RESUMEN

Blood monocyte derived antigen presenting cells (APC) such as dendritic cells and macrophages are considered as major promising tools for antitumoral immunotherapy. In order to contribute to their phenotype characterization, we have precisely investigated their levels of expression of MHC class Ia, Ib (HLA-G) and II molecules using mainly flow cytometry quantification assays. APC were generated from monocytes cultured for 7 days in the presence of GM-CSF and IL-4 or M-CSF. These cells, which exhibited known morphological and immunological features of dendritic cells and macrophages respectively, were evidenced to display high expression of MHC class Ia and class II antigens in comparison to that found in monocytes. Dendritic cells and macrophages thus expressed 2-fold more and 4-fold more MHC class Ia molecules and 5-fold and 3-fold more MHC class II DR molecules than parental monocytes. In addition, expression of MHC class II DP and DQ molecules, not or only barely detected in monocytes, was clearly demonstrated in the two kinds of APC. In contrast, monocytes, dendritic cells and macrophages failed to express MHC class Ib HLA-G antigen. The up-regulation in monocyte-derived APC of MHC class Ia and II molecules mediating the presentation of antigen peptides to lymphocytes fully supports the interest of such APC in antitumoral immunotherapy.


Asunto(s)
Células Dendríticas/inmunología , Antígenos de Histocompatibilidad Clase II/biosíntesis , Antígenos de Histocompatibilidad Clase I/biosíntesis , Macrófagos/inmunología , Monocitos/inmunología , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Antígenos HLA/biosíntesis , Antígenos HLA-G , Humanos , Inmunofenotipificación , Interleucina-4/inmunología , Interleucina-4/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Monocitos/citología , Monocitos/efectos de los fármacos , Células U937
8.
Hum Immunol ; 62(10): 1073-80, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11600213

RESUMEN

P-glycoprotein (P-gp), an ATP-binding cassette (ABC) drug efflux pump, has been recently shown to play an important role in the physiology of Langherans cells, a subtype of dendritic cells (DC) found in the skin. The present study was designed to investigate expression and activity of P-gp and of multidrug resistance-associated protein (MRP), another ABC efflux pump sharing numerous substrates with P-gp, in human monocyte-derived DC. Immunolabeling experiments and dye efflux assays indicated that such cells displayed elevated levels of MRP activity and expression when compared to those present in parental monocytes. Generation of DC from monocytes in the presence of the MRP inhibitor indomethacin did not, however, alter the capacity of DC to stimulate allogeneic T cells proliferation in mixed lymphocyte reaction. In addition, indomethacin did not inhibit the up-regulation of the CD1a, a marker occurring during the differentiation of monocytes into DC. In contrast to that of MRP, functional expression of P-gp was not detected in monocyte-derived DC. Such antigen presenting cells that constitute a promising tool for antitumor vaccinal therapy therefore display differential expression of the efflux pumps P-gp and MRP.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Células Dendríticas/metabolismo , Resistencia a Múltiples Medicamentos/inmunología , Monocitos/metabolismo , Transporte Biológico/efectos de los fármacos , Transporte Biológico/inmunología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/inmunología , Células Cultivadas , Técnicas de Cocultivo , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Fluoresceínas/metabolismo , Técnica del Anticuerpo Fluorescente Indirecta , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Células HL-60 , Humanos , Inmunofenotipificación , Interleucina-4/farmacología , Células K562 , Prueba de Cultivo Mixto de Linfocitos , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Probenecid/farmacología
9.
Hum Immunol ; 61(11): 1086-94, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11137211

RESUMEN

As trophoblast cells and macrophages share cellular characteristics, we investigated the expression of HLA-G antigens during the myelomonocytic differentiation. Analyses with the 87G and 16G1 monoclonal antibodies demonstrated that HLA-G was not expressed in peripheral blood monocytes, in in vitro differentiated dendritic cells and macrophages, and in resident mononuclear phagocytes infiltrating healthy tissues. Conversely, activated macrophages and dendritic cells localized in tumoral biopsies of some lung carcinomas expressed HLA-G antigens. Induction of HLA-G expression at the cell surface of the monohistiocytic cell line U 937 with different cytokines strongly suggests that cytokines secreted during inflammation may be involved in this specific upregulation. Bronchoalveolar macrophages collected from patients suffering from acute HCMV pneumonitis also expressed HLA-G molecules. In vitro, we thus demonstrated that HLA-G antigens are produced during viral reactivation in the macrophages generated after allogeneic stimulation of HCMV latently infected monocytes. Our data suggest that inflammatory processes in lung tissues, like tumoral transformation and HCMV acute infection, are likely to induce HLA-G molecules in infiltrating macrophages and dendritic cells. The expression of molecules capable of downregulating both the innate and adoptive immunity could be a mechanism that helps tumoral and HCMV infected cells to escape immune response.


Asunto(s)
Células Dendríticas/inmunología , Antígenos HLA/biosíntesis , Antígenos de Histocompatibilidad Clase I/biosíntesis , Macrófagos/inmunología , Monocitos/inmunología , Enfermedad Aguda , Biopsia , Carcinoma/inmunología , Carcinoma/patología , Línea Celular , Citocinas/farmacología , Citometría de Flujo , Antígenos HLA/inmunología , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Pulmón/inmunología , Pulmón/patología , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Activación de Macrófagos , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Monocitos/virología , Neumonía Viral/inmunología , Células U937
10.
Hum Immunol ; 41(1): 79-86, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7836069

RESUMEN

Recently, HLA-G transgenic mice were shown to exhibit transgene transcription in several extraembryonic tissues. To determine whether HLA-G mRNAs are also expressed in other human tissues, we have undertaken Northern blot and RT-PCR assays using HLA-G locus-specific probe and primers. These studies demonstrate that the HLA-G gene is transcribed in a variety of cells and adult tissues obtained from different individuals (peripheral blood leukocytes, placenta, skin, spleen, thymus, prostate, testicle, ovary, small intestine, colon, heart, brain, lung, liver, and kidney), as well as in fetal tissues (heart, lung, liver, and kidney). The HLA-G mRNA level observed in most tissues is orders of magnitude lower than the level of classic class I genes in the same tissues. RT-PCR studies have demonstrated that alternative splicing of the HLA-G primary transcript is different from tissue to tissue and could be regulated in a tissue-specific fashion. Sequencing of keratinocyte transcripts has confirmed previous observations: (a) three different alternative splicing transcripts are produced (a full-length transcript, an mRNA lacking exon 3, and a transcript devoid of exon 3 and 4) and (b) HLA-G polymorphism is limited in the coding regions. In view of this wide HLA-G tissue distribution, a new hypothesis dealing with possible HLA-G function is proposed.


Asunto(s)
Antígenos HLA/biosíntesis , Antígenos de Histocompatibilidad Clase I/biosíntesis , Empalme Alternativo/genética , Secuencia de Bases , Northern Blotting , Línea Celular , Antígenos HLA/genética , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Queratinocitos/inmunología , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , Transcripción Genética
11.
Hum Immunol ; 60(10): 944-54, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10566594

RESUMEN

Hematopoietic progenitors express HLA-DR molecules. However the significance of HLA-class II molecules on CD34+ cells remains unknown. The primary role of HLA-class-II molecules is antigen presentation although a second role, that of signal transduction, has been established in B cells. The role of HLA-DR in hematopoiesis was examined by determining the ability of CD34+ progenitor cells to differentiate to "Colony Forming Unit Granulocyte-Macrophage" (CFU-GM) and "Burst Forming Unit Erythrocyte" (BFU-E) in the presence of anti-HLA-DR monoclonal antibody. We observed a reduction in the number of CFU-GM which was due in part to down regulation of granulocyte rather than monocyte differentiation. These observations suggest that HLA-DR signals can regulate myelopoiesis. We point out especially the role of the HLA-DR molecule in the switch of CFU-GM between granulocyte or monocyte lineages. Although HLA-DR mediated apoptosis has been described in mature B lymphocytes apoptosis of CD34+ cells was excluded as a mechanism.


Asunto(s)
Antígenos CD34/aislamiento & purificación , Apoptosis , Granulocitos/citología , Antígenos HLA-DR/metabolismo , Células Madre Hematopoyéticas/citología , Anticuerpos Monoclonales/farmacología , Diferenciación Celular , Ensayo de Unidades Formadoras de Colonias , Proteína Ligando Fas , Hematopoyesis , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/inmunología , Humanos , Antígeno Lewis X/aislamiento & purificación , Receptores de Lipopolisacáridos/aislamiento & purificación , Macrófagos/citología , Glicoproteínas de Membrana/inmunología , Glicoproteínas de Membrana/metabolismo , Monocitos/citología , Receptor fas/inmunología , Receptor fas/metabolismo
12.
Hum Immunol ; 63(2): 83-90, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11821155

RESUMEN

HLA-G is selectively expressed in extravillous trophoblast of human placenta, which does not express classical HLA-A and -B molecules. Several studies report the role of HLA-G as a molecule involved in immune tolerance. By interacting with NK and T cells inhibitory receptors, HLA-G may downregulate their cytotoxicity functions. To appreciate the biologic and clinical relevance of HLA-G expression in lung diseases, HLA class I and HLA-G expression were analyzed in a panel of 36 ex vivo neoplastic tissues and 8 non-neoplastic lung tissues. Immunohistochemical analysis was performed using a pan-HLA class I antibody (W6/32) and three different specific anti-HLA-G antibodies (87G, MEMG/9 and 4H84). These findings demonstrated that HLA-G products were not expressed in pulmonary structural cells. However, HLA-G molecules were detected in activated macrophages and dendritic cells infiltrating lung carcinomas (33%) and nontumoral pulmonary diseases (25%). HLA-G expression was not correlated with classical HLA alterations. No statistical correlation was found between HLA-G expression and clinical or biologic parameters except high tumor size. The expression of HLA-G in myelo-monocytic cells infiltrating lung pathologic tissues could alter antigenic presentation and contribute to decrease immune response efficiency, subsequently favoring the progression of tumoral or inflammatory processes.


Asunto(s)
Células Dendríticas/metabolismo , Enfermedades Pulmonares/metabolismo , Pulmón/metabolismo , Macrófagos/metabolismo , Femenino , Antígenos HLA/metabolismo , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Pulmón/citología , Neoplasias Pulmonares/metabolismo , Masculino
13.
Leuk Res ; 17(12): 1031-5, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7504150

RESUMEN

Rhodamine 123 is transported by the transmembrane efflux pump P glycoprotein (Pgp). We used this fluorescent dye to study multidrug resistance (MDR) activity in normal and leukemic CD34+ cells. These immature cells had a high degree of MDR activity. Among leukemic cells, CD34+ leukemias had significantly higher MDR activity as compared to CD34- leukemias. Heterogeneous results in cell subpopulations, however, indicate that prognosis should be interpreted in the light of MDR analysis.


Asunto(s)
Antígenos CD/análisis , Médula Ósea/patología , Proteínas Portadoras/análisis , Leucemia/patología , Glicoproteínas de Membrana/análisis , Monocitos/patología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Enfermedad Aguda , Antígenos CD34 , Células de la Médula Ósea , Citometría de Flujo , Colorantes Fluorescentes , Estudios de Seguimiento , Humanos , Inmunofenotipificación , Monocitos/citología , Leucemia-Linfoma Linfoblástico de Células Precursoras/clasificación , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Valores de Referencia , Rodamina 123 , Rodaminas , Factores de Tiempo
14.
Int J Oncol ; 15(3): 571-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10427142

RESUMEN

Multidrug resistance-associated protein (MRP) and P-glycoprotein are drug efflux pumps conferring multidrug resistance to tumor cells and sharing numerous substrates. In order to determine a flow cytometric assay allowing to analyse MRP activity in cancerous cells in a sensitive and specific manner, cellular accumulation and efflux of the anionic fluorescent dye carboxy-2',7'-dichlorofluorescein (CDF) were studied by flow cytometry using mainly MRP-overexpressing lung GLC4/Sb30 cells and parental GLC4 cells. GLC4/Sb30 cells were found to display reduced accumulation and enhanced efflux of the dye when compared to their parental counterparts. Probenecid, a well known blocker of MRP, strongly enhanced CDF accumulation in GLC4/Sb30 cells through inhibiting efflux of the dye; it also increased CDF levels in GLC4 cells, although to a lesser extent, which may likely be linked to the low, but detectable, expression of MRP in these cells. Comparison of CDF retention with that of calcein demonstrated that the former dye was the most efficiently effluxed by GLC4/Sb30 cells. In contrast to MRP overexpression, that of P-glycoprotein was not found to alter cellular CDF labelling whereas it strongly impaired calcein staining. These results indicate that CDF is a substrate for MRP, but not for P-gp, which may likely be useful for sensitive and specific flow cytometric determination of MRP activity in clinical samples.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/fisiología , Transportadoras de Casetes de Unión a ATP/fisiología , Colorantes , Resistencia a Múltiples Medicamentos , Fluoresceínas , Proteínas de Neoplasias/fisiología , Aniones , Citometría de Flujo , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Sensibilidad y Especificidad , Células Tumorales Cultivadas
15.
Leuk Lymphoma ; 30(3-4): 381-7, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9713968

RESUMEN

The measurement of rhodamine 123 (Rho123) efflux in hematological malignancies, using flow-cytometry, provides an accurate assessment of multidrug resistance (MDR) of both P-glycoprotein and MRP. While their normal counterparts display high levels of PgP and Rho123 efflux, we investigated the MDR status of marked T/NK proliferations. When diagnosed according to natural killer (NK) markers (CD16, CD56, CD57) 8 of nine NK lymphoproliferative disorders (LPD) were markedly positive (3 NK non Hodgkin's lymphomas (NHL), 1 NK lymphoproliferative disease of large granular lymphocytes (LGL), and 5 T/NK LGL). These results are in accordance with the observed response to chemotherapy in the treated cases. Mature T LPD (prolymphocytic leukemia (PLL), and NHL) cells gave varying results, as did cells from Sezary syndromes. Marked Rho123 efflux was detected in the two cases of T-PLL suggesting the expression of MRP as previously described. Immature T-lymphomas or leukemias (6 cases) were all negative. These data should be considered in relation to NK proliferations which clearly display an MDR phenotype and therefore raise the question, of the relevance of this phenotype in normal cells, and secondly of the negativity of immature T-LPD. The latter could indicate that MDR inhibitors may be superfluous in the initial treatment of acute lymphoblastic leukemia (ALL). Finally the resistance to treatment of T-ALL or mature T cells LPD invokes the importance of exploring other mechanisms of drug resistance such as the lung resistance related protein (LRP).


Asunto(s)
Resistencia a Múltiples Medicamentos , Células Asesinas Naturales/inmunología , Trastornos Linfoproliferativos/tratamiento farmacológico , Linfocitos T/inmunología , Antígenos CD/metabolismo , Colorantes Fluorescentes , Humanos , Inmunofenotipificación , Células Asesinas Naturales/metabolismo , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/inmunología , Trastornos Linfoproliferativos/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Pronóstico , Rodamina 123 , Rodaminas
16.
Life Sci ; 68(11): 1323-31, 2001 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-11233999

RESUMEN

Multidrug resistance proteins (MRPs) such as MRP1, MRP2 and MRP3 are membrane efflux pumps involved in multidrug resistance and handling organic anions. In the present study, MRP activity was investigated in normal mature leucocytes and CD34-positive hematopoietic cells from peripheral blood using the flow cytometric carboxy-2',7'-dichlorofluorescein (CF) efflux assay. Basal and similar cellular exports of CF, an anionic fluorescent dye substrate for MRP1 and MRP2 transporters, were evidenced in lymphocytes whatever their subsets (CD3, CD4, CD8, CD20 and CD56 cells), in CD14 monocytes and in CD15 granulocytes whereas higher CF efflux was found in CD34 cells. Such outwardly-directed transports of CF were inhibited by known blockers of MRP function such as probenecid whereas the P-glycoprotein modulator verapamil did not alter the retention of the dye in the blood leukocytes. Peripheral mature blood leukocytes were moreover found to express MRP1 mRNAs and MRP1 protein as assessed by Northern-blot and Western-blot analyses, whereas MRP2 and MRP3 transcripts were not present or only at very low levels. Mature leukocytes therefore display basal constitutive MRP-related transport activity regardless of cell lineage and likely related to MRP1 expression whereas higher MRP-related efflux can be detected in peripheral CD34 hematopoietic cells.


Asunto(s)
Antígenos CD34/análisis , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Células Madre Hematopoyéticas/metabolismo , Leucocitos/metabolismo , Proteínas Mitocondriales , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Complejo Piruvato Deshidrogenasa , Proteínas Ribosómicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Proteínas de Unión al ADN/genética , Acetiltransferasa de Residuos Dihidrolipoil-Lisina , Citometría de Flujo , Fluoresceínas/metabolismo , Colorantes Fluorescentes/metabolismo , Proteínas Fúngicas/genética , Granulocitos/metabolismo , Células HL-60 , Humanos , Leucocitos/química , Subgrupos Linfocitarios , Linfocitos/metabolismo , Monocitos/metabolismo , Proteína 3 Homóloga de MutS , ARN Mensajero/análisis , Proteínas Ribosómicas/genética
17.
J Biomech ; 35(6): 733-7, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12020992

RESUMEN

Many computer-assisted surgery applications use electromagnetic tracking devices and several sources of interference may reduce the accuracy of this type of system in clinical situations. This study aims to quantify interference sources in an operating room (OR) and determine if their impact on the tracking system is excessive for applications requiring millimetric accuracy. Electromagnetic noise levels were measured in a controlled environment and compared with measurements in an OR. Errors generated by this noise remained below the 0.15mm RMS level. OR equipment was also brought in proximity to the electromagnetic receivers and the errors generated by the ensuing interference were measured. Ferromagnetic and electrical devices can produce large interference (translation errors up to 8.4mm RMS and rotation up to 166 degrees ). However, these devices can be identified and placed at sufficient distances to decrease the magnitude of their interference. In conclusion, in the absence of significant ferromagnetic or electromagnetic distortion caused by equipment often present in an OR, this electromagnetic tracking system provides valid relative measurements with millimetric accuracy to computer-assisted surgical applications. This distortion can be reduced by maximizing the distances to the interfering OR equipment and integrating noise-reducing algorithms in associated software.


Asunto(s)
Campos Electromagnéticos , Fenómenos Electromagnéticos/instrumentación , Movimiento , Telemetría/instrumentación , Artefactos , Calibración , Fenómenos Electromagnéticos/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Compuestos Férricos , Metales , Quirófanos , Sensibilidad y Especificidad , Telemetría/métodos
18.
Spine (Phila Pa 1976) ; 25(5): 606-14, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10749638

RESUMEN

STUDY DESIGN: A comparative study on the position of pedicle screws in patients treated surgically with and without computer assistance. OBJECTIVES: To evaluate the accuracy of computer-assisted pedicle screw installation, and to evaluate its clinical benefit as compared with conventional pedicle screw installation techniques. SUMMARY OF BACKGROUND DATA: In vitro and clinical studies have documented a significant rate of misplaced screws in the thoracolumbar area. Neurologic complications are recognized problems caused by screw misplacement. METHODS: Patients treated surgically with computer assistance were compared with a historical control group of patients treated surgically with conventional techniques in the same hospital and by the same surgical team. All screw positions were measured with a postoperative magnetic resonance tomography, and cortical effractions were categorized in 2-mm increments. Patients' charts also were reviewed to assess individual neurologic outcomes. RESULTS: The control cohort was composed of 100 patients, with 544 screws from T5 to S1. The computer-assisted cohort was composed of 50 patients, with 294 screws from T2 to S1. In the control cohort, 461 of 544 screws (85%) were found completely within their pedicles as compared with 278 of 294 screws (95%) correctly placed in the computer-assisted group (P < 0.0001). All 16 screws incorrectly placed with computer assistance were found 0.1 mm to 2 mm from the pedicle cortex. In the control cohort, 68 screws were found 0.1 mm to 2 mm, 10 screws 2.1 mm to 4 mm, and 5 screws more than 4 mm from the pedicle cortex. Seven patients in the control cohort were surgically retreated because of postoperative neurologic deficits, whereas no patients in the computer-assisted group were surgically retreated. CONCLUSIONS: Computer assistance can decrease the incidence of incorrectly positioned pedicle screws.


Asunto(s)
Tornillos Óseos , Enfermedades de la Columna Vertebral/cirugía , Fusión Vertebral/métodos , Columna Vertebral/cirugía , Terapia Asistida por Computador/métodos , Estudios de Cohortes , Humanos , Vértebras Lumbares/cirugía , Imagen por Resonancia Magnética , Reoperación , Reproducibilidad de los Resultados , Sacro/cirugía , Enfermedades de la Columna Vertebral/diagnóstico , Fusión Vertebral/normas , Terapia Asistida por Computador/normas , Vértebras Torácicas/cirugía , Titanio
19.
Spine (Phila Pa 1976) ; 20(10): 1208-12, 1995 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-7638668

RESUMEN

STUDY DESIGN: We evaluated a computer-assisted surgical tool for inserting pedicle screws. OBJECTIVES: This study reviewed the feasibility, usefulness, and accuracy of the proposed tool. SUMMARY OF BACKGROUND DATA: Reviews documented neurovascular damage caused by screw misplacement. Currently, screw hole position is assessed by radiologic means and curette palpation. METHODS: Three sheep vertebrae and one artificial object were reconstructed three-dimensionally from computed tomography scan slices. At surgery, the surgeon's movements were displayed relative to the three-dimensional vertebrae on a computer screen. The tool was used to detect pedicles and to verify the position of drilled holes. In our laboratory, we calculated the system's accuracy by taking measurements on the artificial object. RESULTS: All pedicles were identified with the computer. Five of the six drilled hole positions were correctly represented. An accuracy of 4.5 mm +/- 1.1 mm RMS (root of the mean squared) and 1.6 degrees +/- 1.2 degrees were calculated. CONCLUSIONS: Results suggested the proposed system could be useful for pedicle detection and assessing the intravertebral location of a drilled hole. The proposed system could be used for many different orthopedic procedures where structures are hidden from the surgeon's view.


Asunto(s)
Tornillos Óseos , Procesamiento de Imagen Asistido por Computador , Vértebras Lumbares/cirugía , Columna Vertebral/cirugía , Animales , Gráficos por Computador , Estudios de Factibilidad , Vértebras Lumbares/diagnóstico por imagen , Ovinos , Programas Informáticos , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X
20.
Ann Biol Clin (Paris) ; 60(6): 663-72, 2002.
Artículo en Francés | MEDLINE | ID: mdl-12446230

RESUMEN

Diagnosis of haematological malignancies is based on multiparametric analysis such as morphology, phenotype and genotype studies. Some entities are only defined by one of these approach. Flow-cytometry (FCM) is useful to determined the normal counterpart of the tumoral process and its differentiation status within the involved lineage. Furthermore, FCM is able to detect clonality in B or T proliferations and criteria for malignancies such as abnormal phenotype. Finally it also specifies prognosis criterias. Among the different haematological malignancies, acute lymphoblastic leukaemia (ALL) can be diagnosed using FCM, whereas acute myeloblastic leukaemia diagnosis is only confirmed by this methodology, which could moreover determine prognosis factors. A scoring system (EGIL) determine the normal counterpart of tumoral cells using a panel of different markers. Immunophenotyping is also useful in chronic lymphoproliferative disorders, such as chronic lymphocytic leukaemia (CLL) by using a similar scoring system (so-called Matutes scoring). Since FCM is able to detect simultaneously numerous cell markers it could be more accurate than immunohistochemistry for the diagnosis of follicular lymphoma, mantle cell lymphoma or hairy cell leukaemia. Finally, during treatment follow-up, minimal residual disease characterised by the detection of rare specific events, may be examined using FCM, in some situations.


Asunto(s)
Citometría de Flujo/métodos , Neoplasias Hematológicas/diagnóstico , Anticuerpos Monoclonales , Biomarcadores de Tumor/análisis , Genotipo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Humanos
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