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Research gaps in understanding flood changes at the catchment scale caused by changes in forest management, agricultural practices, artificial drainage, and terracing are identified. Potential strategies in addressing these gaps are proposed, such as complex systems approaches to link processes across time scales, long-term experiments on physical-chemical-biological process interactions, and a focus on connectivity and patterns across spatial scales. It is suggested that these strategies will stimulate new research that coherently addresses the issues across hydrology, soil and agricultural sciences, forest engineering, forest ecology, and geomorphology.
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BACKGROUND: To investigate the correlation of TargetPrint with local and central immunohistochemistry/fluorescence in situ hybridization assessment of estrogen (ER), progesterone (PgR), and human epidermal growth factor receptor 2 (HER2) in the first 800 patients enrolled in the MINDACT trial. PATIENTS AND METHODS: Data from local (N = 800) and central (N = 626) assessments of receptor status were collected and compared with TargetPrint results. RESULTS: For ER, the positive agreement (the percentage of central pathology positive assessments that were also TargetPrint/local laboratory positive) for TargetPrint in comparison to centralized assessment was 98% with a negative agreement (the percentage of central pathology negative assessments that were also TargetPrint/local laboratory negative) of 96%. For PgR, the positive agreement was 83% with a negative agreement of 92%. For HER2, the positive agreement was 75% with a negative agreement of 99%. Even though the local assessment showed higher positive agreement for PgR (89%) and higher positive agreement for HER2 (85%), the range of discordant local versus central assessments were as high as 6.7% for ER, 12.9% for PgR, and 4.3% for HER2. CONCLUSION: TargetPrint and local assessment of ER, PgR, and HER2 show high concordance with central assessment in the first 800 MINDACT patients. However, there are concerns about the higher discordance rates for some local sites. TargetPrint can improve the reliability of hormone receptor and HER2 testing for those centers with a lower rate of concordance with the reference laboratory, with the limitation of a positive agreement of 75% for HER2. TargetPrint consequently has important implications for treatment decisions in clinical practice and is a reliable alternative to local assessment for ER. CLINICAL TRIALS NUMBER: NCT00433589.
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Neoplasias de la Mama/genética , Biosíntesis de Proteínas/genética , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Adulto , Anciano , Biomarcadores de Tumor/biosíntesis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Humanos , Hibridación Fluorescente in Situ , Análisis por Micromatrices , Persona de Mediana Edad , Pronóstico , ARN Mensajero/biosíntesis , Receptor ErbB-2/biosíntesis , Receptores de Estrógenos/biosíntesis , Estadística como AsuntoRESUMEN
PURPOSE: Pulmonary emboli (PE) contribute substantially to coronavirus disease 2019 (COVID-19) related mortality and morbidity. Immune cell-mediated hyperinflammation drives the procoagulant state in COVID-19 patients, resulting in immunothrombosis. To study the role of peripheral blood mononuclear cells (PBMC) in the procoagulant state of COVID-19 patients, we performed a functional bioassay and related outcomes to the occurrence of PE. Secondary aims were to relate this functional assay to plasma D-dimer levels, ventilation perfusion mismatch and TF expression on monocyte subsets. METHODS: PBMC from an ICU biobank were obtained from 20 patients with a computed tomography angiograph (CTA) proven PE and compared to 15 COVID-19 controls without a proven PE. Functional procoagulant properties of PBMC were measured using a modified fibrin generation time (MC-FGT) assay. Tissue factor (TF) expression on monocyte subsets were measured by flow cytometry. Additional clinical data were obtained from patient records including end-tidal to arterial carbon dioxide gradient. RESULTS: MC-FGT levels were highest in the samples taken closest to the PE detection, similar to the end-tidal to arterial carbon dioxide gradient (ETCO2 - PaCO2), a measurement to quantify ventilation-perfusion mismatch. In patients without proven PE, peak MC-FGT relates to an increase in end-tidal to arterial carbon dioxide gradient. We identified non-classical, CD16 positive monocytes as the subset with increased TF expression. CONCLUSION: We show that the procoagulant state of PBMC could aid in early detection of PE in COVID-19 ICU patients. Combined with end-tidal to ETCO2 - PaCO2 gradient, these tests could improve early detection of PE on the ICU.
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COVID-19 , Embolia Pulmonar , Humanos , Leucocitos Mononucleares , Dióxido de Carbono , Estudios Prospectivos , Embolia Pulmonar/diagnóstico , PerfusiónRESUMEN
Invasive meningococcal disease is associated with significant mortality. Classic presentation consists of high fever, headache and neck stiffness. Neisseria meningitidis serogroup W may present with atypical symptoms, which complicates recognition. Furthermore, it is associated with a high case fatality rate.
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Diarrea/microbiología , Infecciones Meningocócicas/complicaciones , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo W-135 , Sepsis/microbiología , Diagnóstico Diferencial , Diarrea/diagnóstico , Femenino , Humanos , Infecciones Meningocócicas/diagnóstico , Sepsis/diagnóstico , Adulto JovenRESUMEN
Recently, we and others described a new chromosomal rearrangement, that is, inv(7)(p15q34) and t(7;7)(p15;q34) involving the T-cell receptor beta (TCRbeta) (7q34) and the HOXA gene locus (7p15) in 5% of T-cell acute lymphoblastic leukemia (T-ALL) patients leading to transcriptional activation of especially HOXA10. To further address the clinical, immunophenotypical and molecular genetic findings of this chromosomal aberration, we studied 330 additional T-ALLs. This revealed TCRbeta-HOXA rearrangements in five additional patients, which brings the total to 14 cases in 424 patients (3.3%). Real-time quantitative PCR analysis for HOXA10 gene expression was performed in 170 T-ALL patients and detected HOXA10 overexpression in 25.2% of cases including all the cases with a TCRbeta-HOXA rearrangement (8.2%). In contrast, expression of the short HOXA10 transcript, HOXA10b, was almost exclusively found in the TCRbeta-HOXA rearranged cases, suggesting a specific role for the HOXA10b short transcript in TCRbeta-HOXA-mediated oncogenesis. Other molecular and/or cytogenetic aberrations frequently found in subtypes of T-ALL (SIL-TAL1, CALM-AF10, HOX11, HOX11L2) were not detected in the TCRbeta-HOXA rearranged cases except for deletion 9p21 and NOTCH1 activating mutations, which were present in 64 and 67%, respectively. In conclusion, this study defines TCRbeta-HOXA rearranged T-ALLs as a distinct cytogenetic subgroup by clinical, immunophenotypical and molecular genetic characteristics.
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Proteínas de Homeodominio/genética , Leucemia-Linfoma de Células T del Adulto/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Adolescente , Adulto , Niño , Deleción Cromosómica , Inversión Cromosómica , Femenino , Reordenamiento Génico de Linfocito T , Proteínas Homeobox A10 , Humanos , Inmunofenotipificación , Leucemia-Linfoma de Células T del Adulto/patología , Leucemia-Linfoma de Células T del Adulto/fisiopatología , Masculino , Persona de Mediana Edad , Receptor Notch1/genética , Activación Transcripcional , Translocación GenéticaRESUMEN
A retrospective cytogenetic study of acute myeloid leukemias (AML) and myelodysplastic syndromes (MDS) was conducted by the Groupe Francophone de Cytogénétique Hématologique (GFCH) to evaluate the structural abnormalities of chromosome 5 associated with other chromosomal abnormalities, in particular of chromosome 7, in these pathologies. In all, 110 cases of AML/MDS were recruited based on the presence of chromosome 5 abnormalities under conventional cytogenetics and supplemented by a systematic fluorescence in situ hybridization study of chromosomes 5 and 7. The abnormalities of the long arm of chromosome 5 (5q) were deletions of various sizes and sometimes cryptic. The 5q abnormalities were associated with translocations in 54% of cases and were simple deletions in 46%. In 68% of cases, 5q deletions were associated with chromosome 7 abnormalities, and 90% of these presented a complex karyotype. Of the 110 patients, 28 had a hematopoietic disorder secondary to chemotherapy, radiotherapy, or both. Among 82 patients with de novo AML/MDS, 63 were older than 60 years. Chromosomal abnormalities often associated hypodiploidy and chromosome 5 and 7 abnormalities in complex karyotypes, features resembling those of secondary hemopathies. Systematic investigation of the exposure to mutagens and oncogenes is thus essential to specify the factors potentially involved in MDS/AML with 5q abnormalities.
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Aberraciones Cromosómicas , Cromosomas Humanos Par 5 , Cromosomas Humanos Par 7 , Leucemia Mieloide/genética , Síndromes Mielodisplásicos/genética , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Deleción Cromosómica , Femenino , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación , Translocación GenéticaRESUMEN
A 31-year-old patient developed chronic myelogenous leukemia (CML) in November, 1983. In November 1984, following a diagnosis of acceleration, he received an autologous hemopoietic transplant after conditioning with cyclophosphamide and total body irradiation. The autologous marrow was purged with mafosfamide. Over 20 years, the patient remained in chronic phase of CML. Multiple nonrecurrent clonal chromosomal abnormalities appeared leading to a very complex karyotype, including among others involvement of chromosomes 1, 7, 9, 13, 19, and X. Fluorescent in situ hybridization showed that the two chromosomes 9 were involved. Acute myeloid crisis was diagnosed in February, 2004. Treatment with imatinib mesylate resulted within 6 months in a total disappearance of all chromosomal abnormalities with a complete cytogenetic and molecular response, which persists 3 years later. We question whether the ex vivo purging procedure with mafosfamide has favored the occurrence of these particular cytogenetic abnormalities (with no independent oncogenic potential) within the original leukemic stem cell pool. It remains unclear whether the autologous transplantation has indeed resulted into some prolongation of the duration of the chronic phase, which lasted for 20 years. At time of acute crisis, the dramatic response to imatinib mesylate leading to a complete cytogenetic and molecular response is noteworthy.
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Antineoplásicos/uso terapéutico , Trasplante de Médula Ósea , Aberraciones Cromosómicas , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Cromosoma Filadelfia , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Adulto , Benzamidas , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Masculino , Trasplante Autólogo , Irradiación Corporal TotalRESUMEN
The NUP98 gene is fused with 19 different partner genes in various human hematopoietic malignancies. In order to gain additional clinico-hematological data and to identify new partners of NUP98, the Groupe Francophone de Cytogénétique Hématologique (GFCH) collected cases of hematological malignancies where a 11p15 rearrangement was detected. Fluorescence in situ hybridization (FISH) analysis showed that 35% of these patients (23/66) carried a rearrangement of the NUP98 locus. Genes of the HOXA cluster and the nuclear-receptor set domain (NSD) genes were frequently fused to NUP98, mainly in de novo myeloid malignancies whereas the DDX10 and TOP1 genes were equally rearranged in de novo and in therapy-related myeloid proliferations. Involvement of ADD3 and C6ORF80 genes were detected, respectively, in myeloid disorders and in T-cell acute lymphoblastic leukemia (T-ALL), whereas the RAP1GDS1 gene was fused to NUP98 in T-ALL. Three new chromosomal breakpoints: 3q22.1, 7p15 (in a localization distinct from the HOXA locus) and Xq28 were detected in rearrangements with the NUP98 gene locus. The present study as well as a review of the 73 cases previously reported in the literature allowed us to delineate some chromosomal, clinical and molecular features of patients carrying a NUP98 gene rearrangements.
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Neoplasias Hematológicas/genética , Proteínas de Complejo Poro Nuclear/genética , Translocación Genética/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Análisis Citogenético , Femenino , Francia , Proteínas de Homeodominio/genética , Humanos , Hibridación Fluorescente in Situ , Lactante , Masculino , Persona de Mediana Edad , Receptores Citoplasmáticos y Nucleares/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Sociedades MédicasRESUMEN
BACKGROUND: The introduction of sirolimus has provided the opportunity to develop an immunosuppressive regimen without the nephrotoxic calcineurin inhibitors. METHODS: We conducted a first trial in 30 renal allograft recipients. Ten patients were followed prospectively and received sirolimus, to achieve a target blood level of 10 to 15 ng/ml, induction therapy with one dose of daclizumab, low-dose steroids and mycophenolate mofetil. We compared this group with a historical control group of 20 patients who received our standard treatment consisting of tacrolimus, low-dose steroids, and mycophenolate mofetil. RESULTS: After a mean follow-up of 15 weeks, seven patients developed an acute rejection in the sirolimus group (70%) compared with three patients in the tacrolimus group (15%) (p.<0.01). Because of this unacceptable high rate of acute rejections we conducted a second prospective pilot study in nine patients. These patients received sirolimus in combination with two doses of daclizumab, high-dose steroids and mycophenolate mofetil. No rejections occurred under this immunosuppressive regimen; however, many immunosuppression-related adverse events were seen. CONCLUSION: The present study demonstrates an unacceptably high rate of acute rejections (70%) in patients treated with sirolimus, daclizumab, mycophenolate mofetil and low-dose prednisolone. No rejections but many adverse events were seen when sirolimus was given in combination with high-dose steroids.
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Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Trasplante de Riñón , Sirolimus/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Daclizumab , Femenino , Glucocorticoides/uso terapéutico , Humanos , Inmunoglobulina G/uso terapéutico , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapéutico , Prednisolona/uso terapéutico , Sirolimus/efectos adversos , Tacrolimus/uso terapéuticoRESUMEN
Cytogenetic follow-up studies such as those reported after allogeneic bone marrow transplantation are not available in patients submitted to an autologous bone marrow transplantation (ABMT). Of 114 patients with acute leukemia (69 acute myelocytic AML, 43 acute lymphocytic ALL, 2 undifferentiated) who underwent an ABMT in our institution in the period from February 1983 to December 1989, 66 had evaluable cytogenetic data post-transplant. They all received a pretransplant regimen consisting of cyclophosphamide (CY) and total body irradiation (TBI) followed by reinfusion of marrow purged with mafosfamide. Twenty patients showed chromosomal damage at some time; of these, six relapsed early post-ABMT, one died while in persisting remission at 81 months post-ABMT from overwhelming pneumococcal sepsis related to a previous splenectomy, and 13 are still alive and well at 13 to 88 months post-transplant. The bone marrow cytogenetic abnormalities were complex: they included various numbers of clonal aberrations or variations or combination of those; they affected all but the Y chromosome, with a predominance however for chromosomes 1, 3, 6, and 7; they were often transitory and in some instances became modified with time. None of these chromosomal abnormalities was connected with the initial leukemia, even in the 6 patients who relapsed early. In the other 14 patients, these abnormalities have so far had no detectable unfavourable implication. The origin of these abnormalities is unknown: both the pretransplant regimen (CY and/or TBI) and/or marrow purging with mafosfamide can be incriminated. Additional studies in patients autografted with pretransplant regimen not containing TBI and/or with unpurged marrow are necessary to discriminate between these two possibilities.
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Antineoplásicos , Purgación de la Médula Ósea , Aberraciones Cromosómicas , Ciclofosfamida/análogos & derivados , Leucemia/genética , Femenino , Humanos , Leucemia/cirugía , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/cirugía , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirugía , Factores de Tiempo , Trasplante Autólogo , Resultado del TratamientoRESUMEN
To accurately estimate the incidence of HOX11L2 expression, and determine the associated cytogenetic features, in T-cell acute lymphoblastic leukemia (T-ALL), the Groupe Français de Cytogénétique Hématologique (GFCH) carried out a retrospective study of both childhood and adult patients. In total, 364 patients were included (211 children =15 years and 153 adults), and 67 (18.5%) [47 children (22.4%) and 20 adults (13.1%)] were shown to either harbor the t(5;14)q35;q32) translocation or express the HOX11L2 gene or both. Most of the common hematological parameters did not show significant differences within positive and negative populations, whereas the incidence of CD1a+/CD10+ and cytoplasmic CD3+ patients was significantly higher in positive than in negative children. Out of the 63 positive patients investigated by conventional cytogenetics, 32 exhibited normal karyotype, whereas the others 31 showed clonal chromosome abnormalities, which did not include classical T-ALL specific translocations. Involvement of the RANBP17/HOX11L2 locus was ascertained by fluorescence in situ hybridization in six variant or alternative (three-way translocation or cytogenetic partner other than 14q32) translocations out of the 223 patients. Our results also show that HOX11L2 expression essentially occurs as a result of a 5q35 rearrangement, but is not associated with another identified T-ALL specific recurrent genetic abnormality, such as SIL-TAL fusion or HOX11 expression.
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Cromosomas Humanos Par 14/genética , Cromosomas Humanos Par 5/genética , Proteínas de Homeodominio/genética , Leucemia-Linfoma de Células T del Adulto/genética , Proteínas Oncogénicas/genética , Translocación Genética , Adolescente , Adulto , Niño , Preescolar , Aberraciones Cromosómicas , Células Clonales , Femenino , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Ploidias , Proteínas Proto-Oncogénicas , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de SupervivenciaRESUMEN
Imatinib mesylate (Gleevec), an inhibitor of the BCR-ABL tyrosine kinase, was introduced recently into the therapy of chronic myeloid leukemia (CML). Several cases of emergence of clonal chromosomal abnormalities after therapy with imatinib have been reported, but their incidence, etiology and prognosis remain to be clarified. We report here a large series of 34 CML patients treated with imatinib who developed Philadelphia (Ph)-negative clones. Among 1001 patients with Ph-positive CML treated with imatinib, 34 (3.4%) developed clonal chromosomal abnormalities in Ph-negative cells. Three patients were treated with imatinib up-front. The most common cytogenetic abnormalities were trisomy 8 and monosomy 7 in twelve and seven patients, respectively. In 15 patients, fluorescent in situ hybridization with specific probes was performed in materials archived before the initiation of imatinib. The Ph-negative clone was related to previous therapy in three patients, and represented a minor pre-existing clone that expanded after the eradication of Ph-positive cells with imatinib in two others. However, in 11 patients, the new clonal chromosomal abnormalities were not detected and imatinib may have had a direct effect. No myelodysplasia was found in our cohort. With a median follow-up of 24 months, one patient showed CML acceleration and two relapsed.
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Aberraciones Cromosómicas , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mieloide Crónica Atípica BCR-ABL Negativa/genética , Leucemia Mieloide Crónica Atípica BCR-ABL Negativa/patología , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Adulto , Anciano , Aneuploidia , Benzamidas , Cromosomas Humanos Par 7 , Cromosomas Humanos Par 8 , Células Clonales/patología , Femenino , Humanos , Mesilato de Imatinib , Incidencia , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios RetrospectivosRESUMEN
Between June 1979 and October 1983, 14 autografts were performed in 13 patients with CML (ten blast crisis, four accelerated phase). Results were disappointing: four patients died during aplasia; seven returned to chronic phase, but three died of hemorrhage, four relapsed, and three did not reverse. The main problem was the very low rate of successful engraftment. Both the collection of bone marrow after treatment with busulfan and a particular sensitivity of CFU-GM to cryoinjury were responsible for the infusion of very low doses of CFU-GM. However, we observed some promising results: In one patient in acute blast crisis, the Ph 1 chromosome disappeared, as well as the cytogenetic marker of transformation; in another patient with acute pure cytogenetic acceleration, the abnormal clone disappeared for 27 months; a third patient was maintained in a second chronic phase for 20 months. Thus we suggest that the results of autografting in chronic myeloid leukemia would be improved by infusing the largest possible dose of stem cells collected before or long after treatment by busulfan, and freezing them following a careful program.
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Trasplante de Médula Ósea , Leucemia Mieloide/terapia , Transfusión de Plaquetas , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Terapia Combinada , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Femenino , Humanos , Cariotipificación , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/radioterapia , Lomustina/administración & dosificación , Masculino , Persona de Mediana Edad , Tioguanina/administración & dosificación , Trasplante AutólogoRESUMEN
Several prospective randomized trials in acute myelocytic leukemia (AML) documented a lower relapse rate with autologous bone marrow transplantation (ABMT) than with conventional chemotherapy. However, they also identified some transplant difficulties, such as failure to collect sufficient numbers of stem cells, slow kinetics of engraftment, and a high transplant-related mortality that diminished or negated positive impact on overall survival. Data for ABMT are inconclusive in acute lymphocytic leukemia (ALL) in adults. We retrospectively analyzed patients with acute leukemia autografted with marrow purged with mafosfamide after January 1983 in our institution. The population comprised 229 consecutive patients; 165 with AML [123 in first remission (CR1), 32 in second remission (CR2)]; 61 with ALL (46 in CR1, 4 in CR2); and 3 with undifferentiated acute leukemia. All patients were autografted with marrow purged with mafosfamide. Mafosfamide was given at a constant dose of 50 microg/mL in 103 and adjusted individually to produce a CFU-GM LD 95 (5% residual CFU-GM post purging) in 126. The outcome was analyzed for correlation with patient characteristics, the disease including cytogenetics, and the graft itself. Prognostic factors identified by multivariate analysis were used to derive a prognostic classification. Patients receiving higher doses of marrow submitted to purging (>5.46 x 10(4) CFU-GM/kg) experienced a lower treatment-related mortality (RR = 0.11, p = 0.005) and a higher leukemia-free (RR = 0.5, p = 0.005) and overall survival (RR = 0.4, p = 0.001). Patients receiving <0.004% CFU-GM of marrow actually infused post purging had a lower relapse rate (RR = 0.51, p = 0.003). Modeling of prognostic groups identified good-, intermediate-, and poor-risk categories. Patients receiving a stem cell dose evaluated before purging of >5.46 x 10(4) CFU-GM/kg and doses actually infused post purging of < or =0.02 x 10(4)/kg had a treatment-related mortality of only 2+/-2%, a leukemia-free survival of 70%, and an overall survival of 77+/-7% at 10 years. In this study of autotransplantation for acute leukemia using mafosfamide-purged marrow, the stem cell dose used for purging and the intensity of purging were the most important factors predicting outcome.
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Antineoplásicos/farmacología , Purgación de la Médula Ósea , Trasplante de Médula Ósea , Ciclofosfamida/análogos & derivados , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Anciano , Antineoplásicos/uso terapéutico , Recuento de Células , Niño , Ciclofosfamida/farmacología , Ciclofosfamida/uso terapéutico , Femenino , Supervivencia de Injerto , Humanos , Leucemia Mieloide Aguda/fisiopatología , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Trasplante Homólogo , Resultado del TratamientoRESUMEN
1. To investigate the role of long-term stimulation of nicotinic acetylcholine receptors (AChRs) on the regulation of membrane potential, non-contracting C2C12 myotubes were stimulated for 1-4 days with carbachol (10 microM) and membrane potentials were measured by the intracellular microelectrode technique after washing out of the drug. 2. The membrane potential (-45.7 mV) gradually increased by 10.1 mV to -55.8 mV during 4 days treatment, which was caused by enhanced electrogenic Na+/K(+)-pumping. 3. The concentration-dependent enhancement of Na+/K(+)-ATPase activity in long-term carbachol-treated myotubes (4 days, EC50 = 5.3 microM) was prevented by co-treatment with the competitive nicotinic AChR antagonist, pancuronium but not by the muscarinic antagonist, atropine. 4. Enhanced Na+/K(+)-ATPase activity still developed in carbachol-stimulated myotubes during co-treatment (4 days) with the nicotinic AChR-channel blocker, chlorpromazine (1 microM). Membrane depolarization as such, obtained by incubation in high K+ medium (40 mM, 4 days) did not enhance Na+/K(+)-ATPase activity. 5. Non-treated myotubes possessed a high-affinity ouabain binding site (Kd = 119 nM) in association with the low Na+/K(+)-pumping activity. Long-term stimulation of myotubes (4 days) with carbachol or with a combination of carbachol and chlorpromazine was accompanied by the development of an additional low-affinity ouabain binding site (Kd = 13 microM). 6. Binding of monoclonal antibodies directed against either alpha 1- or alpha 2-subunit of Na+/K(+)-ATPase were both increased in myotubes treated with carbachol (4 days). 7. These results support the concept that nicotinic AChRs regulate Na+/K(+)-ATPase activity, independent of the functionality of the receptor-operated ion-channel.
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Microtúbulos/enzimología , Músculos/enzimología , Receptores Colinérgicos/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/biosíntesis , Animales , Anticuerpos Monoclonales , Carbacol/farmacología , Línea Celular , Antagonistas Colinérgicos , Electrofisiología , Inducción Enzimática/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Ratones , Microtúbulos/efectos de los fármacos , Músculos/efectos de los fármacos , Músculos/ultraestructura , Ouabaína/farmacocinética , Receptores Colinérgicos/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/inmunología , Regulación hacia Arriba/efectos de los fármacosRESUMEN
1. The response of C2C12 mouse myotubes to stimulation with adenosine triphosphate (ATP) and other nucleotides was studied by measuring changes in membrane potential. 2. A transient hyperpolarization followed by a slowly declining depolarization of the cells was observed in the presence of ATP (10 microM-1 mM). 3. The hyperpolarization was not observed in the absence of external calcium, and was abolished in the presence of tetraethylammonium (20 mM) or the bee toxin, apamin (0.1 microM). The depolarization was reduced under low sodium conditions. 4. A biphasic change in membrane potential was also recorded in the presence of adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S) and the pyrimidine uridine triphosphate (UTP), while the ATP derivatives and analogues, adenosine diphosphate, adenosine, alpha,beta-methylene ATP and 2-methylthio ATP and the nucleotides, guanosine triphosphate and cytidine triphosphate, did not affect the membrane potential of the myotubes. 5. The hyperpolarization elicited by ATP gamma S or UTP was also blocked by apamin and abolished under Ca(2+)-free conditions. 6. In contrast to ATP and ATP gamma S, the depolarization evoked by UTP was unaffected under low Na+ and less sensitive to the antagonistic action of suramin. 7. The ATP and UTP responses at maximal concentration were not additive after simultaneous application. ATP elicited a depolarization if applied after UTP, while UTP did not change membrane potential following the application of ATP. 8. The concentration-response curves of the effective nucleotides were shifted to the right in the presence of suramin, suggesting competitive antagonism.9. These results can be explained by the presence of 'nucleotide receptors' mediating the ATP/UTPinduced hyperpolarization and depolarization in C2C12 myotubes. Furthermore, an increase in Na+-conductivity can be exclusively activated by ATP.
Asunto(s)
Músculos/química , Receptores Purinérgicos/análisis , Adenosina Trifosfato/farmacología , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Potenciales de la Membrana/efectos de los fármacos , Ratones , Músculos/efectos de los fármacos , Nucleótidos/farmacología , Receptores Purinérgicos/efectos de los fármacosRESUMEN
1. The effects of the specific protein kinase C (PKC) inhibitor, GF109203X, were measured on the cytoplasmic Ca2+ concentration ([Ca2+]i), and on histamine H1 receptor- and thapsigargin-mediated increases in [Ca2+]i in DDT1 MF-2 smooth muscle cells. 2. After pretreatment of cells with GF109203X (5 microM, 45 min), the histamine (100 microM)-induced initial rise in [Ca2+]i, representing Ca2+ mobilization from internal stores, was inhibited (by 59 +/- 7%). The slowly declining phase of the histamine induced Ca2+ response, reflecting Ca2+ entry, was enhanced (83 +/- 26%) in the presence of the PKC inhibitor. 3. The histamine induced release of Ca2+ from internal stores, measured after blocking Ca2+ entry with LaCl3 was inhibited by GF109203X in a concentration-dependent manner (IC50: 3.1 +/- 1.1 microM). 4. Histamine-induced formation of inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) was not changed in the presence of GF109203X. 5. The PKC activating phorbol ester, phorbol 12-myristate 13-acetate (PMA, 1 microM), strongly reduced histamine-induced Ins(1,4,5)P3 formation (58 +/- 16%). This effect was reversed by GF109203X (5 microM). Furthermore, PMA diminished histamine evoked Ca2+ release (50 +/- 6%) and blocked Ca2+ entry completely. 6. The rise in [Ca2+]i caused by blocking endoplasmic reticulum Ca2(+)-ATPase with thapsigargin (1 microM), was strongly reduced (57 +/- 3%) after pretreatment of cells with GF109203X. Downregulation of PKC by long-term pretreatment of cells with PMA (1 microM, 48 h) did not abolish this effect of GF109203X (48 +/- 3% inhibition). 7. In permeabilized DDT, MF-2 cells preloaded with 45Ca2+ in the presence of GF109203X, the amount of 45Ca2+ released by Ins(1,4,5)P3 (10 microM) was markedly reduced (42 +/- 9%). GF109203X did not release Ca2+ itself and did not impair Ins(1,4,5)P3 receptor function. 8. Uptake of 45Ca2+ by intact cells, representing Ca2+ entry, was enhanced by GF109203X (65 +/- 11%), by histamine (24 +/- 6%) and also by thapsigargin (121 +/- 10%). The GF109203X- and the thapsigargin-induced uptake of 45Ca2+ were not additive. 9. These data suggest that GF109203X reduces the filling-state of intracellular Ins(1,4,5)P3 sensitive Ca2+ stores by inhibiting the Ca2+ uptake into these stores, thereby promoting store-dependent (capacitive) Ca2+ entry.
Asunto(s)
Calcio/metabolismo , Inhibidores Enzimáticos/farmacología , Indoles/farmacología , Maleimidas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Animales , Línea Celular , Cricetinae , Histamina/farmacología , Mesocricetus , Fosfolipasas de Tipo C/metabolismoRESUMEN
A 41-year-old female patient with a pre-B ALL expressing 2 BCR/ABL transcripts e1/a2 and b2/a2 underwent autologous bone marrow transplantation (aBMT) with marrow grown in long-term culture (LTC) for consolidation of remission (CR). After failing to engraft on day 54 she received her back-up marrow. She engrafted by day 23 and developed a full-blown leukemic relapse 2 weeks later. She died from tumor progression 3 months after infusion of the backup marrow. Analysis of the BCR/ABL transcripts weakly positive at time of collection of the backup marrow, negative in the LTC marrow and in the patient after infusion of the LTC marrow, again positive from day 29 after infusion of the backup marrow until death, strongly suggests that infusion of residual tumor cells with the backup marrow contributed to the relapse.
Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Células Madre Neoplásicas/trasplante , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Purgación de la Médula Ósea , Criopreservación , Resultado Fatal , Femenino , Humanos , Infusiones Intravenosas , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Recurrencia , Trasplante AutólogoRESUMEN
A hundred and eight patients less than 60 years old with de novo acute myeloid leukemia were treated between 1982 and 1994 by protocols including final intensification with a transplant using autologous bone marrow purged by mafosfamide in first remission in the absence of an HLA-matched sibling donor available for allograft. From 1989, we attempted to improve tumor control by using high-dose anthracyclines in induction, by increasing from one to two the number of consolidation courses pre-transplant and by introducing intermediate doses of cytarabine in the first consolidation course. The CR rate was 77% (33/43) before 1989 and 90% (59/65) after 1989 (P = 0.06). Forty-five out of the 59 patients (76%) who achieved CR after 1989 could undergo bone marrow grafting in CR1 vs 16/33 (48%) before 1989 (P = 0.01). In spite of the higher proportion of patients above 50 years after 1989 (32%) toxicity was mild and an adequate graft was obtained more frequently after one collection. The principal factor relating to improvement in graft feasibility was the post-1989 modification of induction and consolidation regimens. This improvement in graft feasibility was associated with a better disease-free survival (DFS) (48 +/- 7% vs 32 +/- 8%, P = 0.04) and overall survival (OS) (53 +/- 6% vs 30 +/- 7%, P = 0.007) at 5 years. By multivariate analysis four factors were associated with overall survival (OS): karyotype, white blood cell count at diagnosis, treatment regimen and bone marrow grafting in CR1. This global approach should be prospectively compared with intensive chemotherapy.