Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
1.
Gut ; 67(2): 237-243, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28053054

RESUMEN

OBJECTIVE: Ciclosporin and infliximab have demonstrated short-term similar efficacy as second-line therapies in patients with acute severe UC (ASUC) refractory to intravenous steroids. The aim of this study was to assess long-term outcome of patients included in a randomised trial comparing ciclosporin and infliximab. DESIGN: Between 2007 and 2010, 115 patients with steroid-refractory ASUC were randomised in 29 European centres to receive ciclosporin or infliximab in association with azathioprine. Patients were followed until death or last news up to January 2015. Colectomy-free survival rates at 1 and 5 years and changes in therapy were estimated through Kaplan-Meier method and compared between initial treatment groups through log-rank test. RESULTS: After a median follow-up of 5.4 years, colectomy-free survival rates (95% CI) at 1 and 5 years were, respectively, 70.9% (59.2% to 82.6%) and 61.5% (48.7% to 74.2%) in patients who received ciclosporin and 69.1% (56.9% to 81.3%) and 65.1% (52.4% to 77.8%) in those who received infliximab (p=0.97). Cumulative incidence of first infliximab use at 1 and 5 years in patients initially treated with ciclosporin was, respectively, 45.7% (32.6% to 57.9%) and 57.1% (43.0% to 69.0%). Only four patients from the infliximab group were subsequently switched to ciclosporin. Three patients died during the follow-up, none directly related to UC or its treatment. CONCLUSIONS: In this cohort of patients with steroid-refractory ASUC initially treated by ciclosporin or infliximab, long-term colectomy-free survival was independent from initial treatment. These long-term results further confirm a similar efficacy and good safety profiles of both drugs and do not favour one drug over the other. TRIAL REGISTRATION NUMBER: EudraCT: 2006-005299-42; ClinicalTrials.gouv number: NCT00542152; post-results.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Ciclosporina/uso terapéutico , Fármacos Gastrointestinales/uso terapéutico , Inmunosupresores/uso terapéutico , Infliximab/uso terapéutico , Adulto , Colectomía , Colitis Ulcerosa/cirugía , Supervivencia sin Enfermedad , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esteroides/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
2.
Gut ; 65(9): 1447-55, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26353983

RESUMEN

BACKGROUND: Crohn's disease (CD) is a chronic disabling and progressive IBD. Only strategies looking beyond symptoms and based on tight monitoring of objective signs of inflammation such as mucosal lesions may have the potential for disease modification. Endoscopic evaluation is currently the gold standard to assess mucosal lesions and has become a major therapeutic endpoint in clinical trials. Several endoscopic indices have been proposed to evaluate disease activity; unvalidated and arbitrary definitions have been used in clinical trials for defining endoscopic response and endoscopic remission in CD. METHODS: In these recommendations from the International Organization for the Study of Inflammatory Bowel Disease, we first reviewed all technical aspects of available endoscopic scoring systems in the literature. Second, in order to achieve consensus on endoscopic definitions of remission and response in trials, a two-round vote based on a Delphi method was performed among 14 specialists in the field of IBDs. RESULTS: At the end of the voting process, the investigators ranked first a >50% decrease in Simple Endoscopic Score for Crohn's Disease (SES-CD) or Crohn's Disease Endoscopic Index of Severity for the definition of endoscopic response, and an SES-CD 0-2 for the definition of endoscopic remission in CD. All experts agreed on a Rutgeerts' score i0-i1 for the definition of endoscopic remission after surgery.


Asunto(s)
Enfermedad de Crohn , Endoscopía Gastrointestinal , Monitoreo Fisiológico , Proyectos de Investigación/normas , Ensayos Clínicos como Asunto , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/terapia , Endoscopía Gastrointestinal/métodos , Endoscopía Gastrointestinal/normas , Humanos , Mucosa Intestinal/diagnóstico por imagen , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/normas , Gravedad del Paciente , Inducción de Remisión , Índice de Severidad de la Enfermedad
3.
Am J Gastroenterol ; 106(4): 771-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21386832

RESUMEN

OBJECTIVES: Rescue therapy with either cyclosporine (CYS) or infliximab (IFX) is an effective option in patients with intravenous steroid-refractory attacks of ulcerative colitis (UC). In patients who fail, colectomy is usually recommended, but a second-line rescue therapy with IFX or CYS is an alternative. The aims of this study were to investigate the efficacy and tolerance of IFX and CYS as a second-line rescue therapy in steroid-refractory UC or indeterminate colitis (IC) unsuccessfully treated with CYS or IFX. METHODS: This was a retrospective survey of patients seen during the period 2000-2008 in the GETAID centers. Inclusion criteria included a delay of <1 month between CYS withdrawal (when used first) and IFX, or a delay of <2 months between IFX (when used first) and CYS, and a follow-up of at least 3 months after inclusion. Time-to-colectomy, clinical response, and occurrence of serious adverse events were analyzed. RESULTS: A total of 86 patients (median age 34 years; 49 males; 71 UC and 15 IC) were successively treated with CYS and IFX. The median (± s.e.) follow-up time was 22.6 (7.0) months. During the study period, 49 patients failed to respond to the second-line rescue therapy and underwent a colectomy. The probability of colectomy-free survival (± s.e.) was 61.3 ± 5.3% at 3 months and 41.3 ± 5.6 % at 12 months. A case of fatal pulmonary embolism occurred at 1 day after surgery in a 45-year-old man. Also, nine infectious complications were observed during the second-line rescue therapy. CONCLUSIONS: In patients with intravenous steroid-refractory UC and who fail to respond to CYS or IFX, a second-line rescue therapy may be effective in carefully selected patients, avoiding colectomy within 2 months in two-thirds of them. The risk/benefit ratio should still be considered individually.


Asunto(s)
Antiinflamatorios/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Colitis Ulcerosa/tratamiento farmacológico , Ciclosporina/administración & dosificación , Resistencia a Medicamentos , Terapia Recuperativa/métodos , Esteroides/administración & dosificación , Administración Oral , Adolescente , Adulto , Antiinflamatorios/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Niño , Colectomía , Colitis Ulcerosa/cirugía , Ciclosporina/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Infecciones/inducido químicamente , Infliximab , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Embolia Pulmonar/inducido químicamente , Embolia Pulmonar/mortalidad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
4.
J Crohns Colitis ; 15(6): 1000-1008, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-33313808

RESUMEN

BACKGROUND AND AIMS: Defining and assessing the reproducibility of Crohn's disease [CD] endoscopic lesions is essential in assessing endoscopic healing. METHODS: Twelve endoscopic CD experts from the GETAID defined aphthoid erosions [AE], superficial ulcerations [SU], deep ulcerations [DU], stenosis, and fistulas according to a Delphi-like method. Thirty different GETAID physicians declared if they found acceptable each definition. Intra- and inter-observer agreements were investigated using 100 videos with one tagged specific lesion [AE, SU, DU, or sham lesion] read by 15 independent endoscopists at baseline and 1 month later in a randomised order. Video quality was determined by an external reader. According to kappa estimate [κ ±standard error], intra or inter-observer agreement was qualified as 'moderate' [0.4-0.6], 'substantial' [0.6-0.8], or 'almost perfect' [0.8-1.0]. RESULTS: Among 30 different experts, 83% to 97% found acceptable the definitions retrieved from the Delphi-like method. Intra-observer κ was 0.717 [±0.019] for SU, 0.681 [±0.027] for AE, 0.856 [±0.014] for DU, showing 'substantial' agreement. It was 0.801 [±0.016] for any ulceration [DU or SU]. There was a high variability across readers from 'moderate' to 'almost perfect' agreement. Inter-observer κ was 0.548 [±0.042] for SU, 0.554 [±0.028] for AE 0.694 [±0.041] for DU, and 0.705 [±0.042] for any ulceration. Inter-observer agreement increased when reading the 53 high-quality videos: 0.787 [±0.064] [p = 0.001], 0.607 [±0.043] [p = 0.001], and 0.782 [±0.064][p = 0.001] for DU, AE, and any ulceration, respectively. CONCLUSIONS: Despite variable intra-agreement level across readers, the GETAID definitions for CD endoscopic lesions provided 'substantial' inter-observer agreements, especially in case of high-quality videos.


Asunto(s)
Enfermedad de Crohn/diagnóstico , Endoscopía Gastrointestinal , Intestinos , Técnica Delphi , Endoscopía Gastrointestinal/métodos , Endoscopía Gastrointestinal/normas , Endoscopía Gastrointestinal/estadística & datos numéricos , Humanos , Intestinos/diagnóstico por imagen , Intestinos/patología , Microscopía por Video/métodos , Variaciones Dependientes del Observador , Mejoramiento de la Calidad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Terminología como Asunto
5.
Br J Dermatol ; 161(1): 153-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19416243

RESUMEN

BACKGROUND: Photographic severity scales depicting facial wrinkling are used extensively to assess the severity of skin ageing features, but they have been poorly investigated for their reproducibility. OBJECTIVES: To investigate the reproducibility of ordinal scales depicting four skin ageing features illustrated by reference photographs. METHODS: A set of 253 images of caucasian women's faces was evaluated independently by four dermatologists using four different skin ageing severity scales: Larnier's overall photodamage, expression lines, glabellar frown lines, and wrinkles under the eyes. For each pair of dermatologists, degree of agreement was estimated using the weighted kappa statistic and degrees of distinguishability between adjacent categories along these scales were estimated using a recently developed log-linear method. RESULTS: The kappa statistic highlighted substantial degrees of agreement between dermatologists for the glabellar frown lines scale, and the log-linear method did not evidence any scale defect. For the three other scales, only fair to moderate degrees of agreement were observed between dermatologists. In addition, difficulties in distinguishing between some adjacent categories were evidenced. CONCLUSIONS: The glabellar frown lines scale is a reproducible tool for assessment of the severity of facial wrinkling. The other scales should be redefined to improve their reproducibility, and therefore their quality, in future studies.


Asunto(s)
Dermatología/métodos , Fotograbar/normas , Envejecimiento de la Piel/fisiología , Adulto , Anciano , Cara/fisiología , Femenino , Humanos , Persona de Mediana Edad , Estándares de Referencia , Reproducibilidad de los Resultados
6.
Gastroenterol Clin Biol ; 33(1 Pt 1): 31-40, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19118966

RESUMEN

AIM: This study aimed to test the efficacy of mesalazine in maintaining remission in pediatric Crohn's disease (CD) following successful flare-up treatment. METHODS: In this double-blind, randomized, placebo-controlled trial, 122 patients received either mesalazine 50mg/kg per day (n=60) or placebo (n=62) for one year. Treatment allocation was stratified according to flare-up treatment (nutrition or medication alone). Recruitment was carried out over two periods, as the first period's results showed a trend favoring mesalazine. Relapse was defined as a Harvey-Bradshaw score more than or equal to 5. Time to relapse was analyzed using the Cox model. RESULTS: The one-year relapse rate was 57% (n=29) and 63% (n=35) in the mesalazine and placebo groups, respectively. We demonstrated a twofold lower relapse risk (P<0.02) in patients taking mesalazine in the medication stratum (first recruitment period), and a twofold higher risk in patients taking mesalazine in the nutrition stratum (second recruitment period), compared with the other groups. None of the children's characteristics, which differed across the two recruitment periods, accounted for the between-period variation in mesalazine efficacy. One serious adverse event was reported in each treatment group. CONCLUSION: Overall, mesalazine does not appear to be an effective maintenance treatment in pediatric CD.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Enfermedad de Crohn/tratamiento farmacológico , Mesalamina/uso terapéutico , Niño , Método Doble Ciego , Femenino , Humanos , Masculino , Prevención Secundaria , Resultado del Tratamiento
7.
Rev Epidemiol Sante Publique ; 57(5): 361-72, 2009 Oct.
Artículo en Francés | MEDLINE | ID: mdl-19674855

RESUMEN

BACKGROUND: Statistical analysis of a data set with missing data is a frequent problem to deal with in epidemiology. Methods are available to manage incomplete observations, avoiding biased estimates and improving their precision, compared to more traditional methods, such as the analysis of the sub-sample of complete observations. METHODS: One of these approaches is multiple imputation, which consists in imputing successively several values for each missing data item. Several completed data sets having the same distribution characteristics as the observed data (variability and correlations) are thus generated. Standard analyses are done separately on each completed dataset then combined to obtain a global result. In this paper, we discuss the various assumptions made on the origin of missing data (at random or not), and we present in a pragmatic way the process of multiple imputation. A recent method, Multiple Imputation by Chained Equations (MICE), based on a Monte-Carlo Markov Chain algorithm under missing at random data (MAR) hypothesis, is described. An illustrative example of the MICE method is detailed for the analysis of the relation between a dichotomous variable and two covariates presenting MAR data with no particular structure, through multivariate logistic regression. RESULTS: Compared with the original dataset without missing data, the results show a substantial improvement of the regression coefficient estimates with the MICE method, relatively to those obtained on the dataset with complete observations. CONCLUSION: This method does not require any direct assumption on joint distribution of the variables and it is presently implemented in standard statistical software (Splus, Stata). It can be used for multiple imputation of missing data of several variables with no particular structure.


Asunto(s)
Métodos Epidemiológicos , Método de Montecarlo , Humanos
8.
Aliment Pharmacol Ther ; 45(6): 801-813, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28112419

RESUMEN

BACKGROUND: Recently, endpoints for clinical trials have been changing from measuring clinical response to mucosal healing in ulcerative colitis. Endoscopic evaluation is the current gold standard to assess mucosal lesions and has become a major measure of therapeutic efficacy in addition to patients reported outcomes. AIM: To achieve consensus on endoscopic definitions of remission and response for clinical trials in patients with ulcerative colitis. METHODS: In reaching the current international recommendations on an International Organization For the Study of Inflammatory Bowel Disease (IOIBD) initiative, we first performed a systematic review of technical aspects of endoscopic scoring systems. Then, to achieve consensus on endoscopic definitions of remission and response for clinical trials, we conducted a two-round vote using a Delphi-style process among fifteen specialists in the field of inflammatory bowel diseases. RESULTS: The literature review showed that many endoscopic indices have been proposed to evaluate disease activity in ulcerative colitis; most are unvalidated and arbitrary definitions have been used in clinical trials for defining endoscopic response or remission. At the end of the voting process, the investigators ranked initially the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) 0 for the definition of endoscopic remission, and a decrease in Mayo endoscopic score ≥1 grade or a decrease in UCEIS ≥2 points for the definition of endoscopic response in ulcerative colitis. CONCLUSIONS: These international recommendations represent the first consensus on measurement indices for endoscopic outcomes in ulcerative colitis. They should be subject to prospective testing in clinical trials of ulcerative colitis.


Asunto(s)
Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/terapia , Consenso , Endoscopía/normas , Internacionalidad , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/normas , Endoscopía/métodos , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/terapia , Estudios Prospectivos , Inducción de Remisión , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
9.
Placenta ; 27(9-10): 989-95, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16359728

RESUMEN

Mechanisms of HIV-1 in utero mother-to-child transmission (MTCT) protection provided by AZT are not completely understood. The placental cytokine network is involved in the control of HIV-1 in utero transmission but the effect of AZT on this network is unknown. To evaluate the effects of AZT on placental cytokine expression, the chorionic villi from HIV-1 uninfected women term placentae were cultured with 0, 100, and 2,000 ng/ml AZT. Tissue fragments were harvested at days 1, 4, and 7 to determine the level of cytokine mRNA by real-time RT-PCR. The viability and morphology of the placental histocultures were monitored by the expression of beta-human chorionic gonadotropin (beta-hCG) gene, lipopolysaccharide (LPS) activation, and microscopic examination. AZT at 2,000 ng/ml significantly down-regulated TNF-alpha mRNA expression at day 1 and day 4, but had no effect on beta-hCG, stromal cell-derived factor 1 (SDF-1), and IL-10 gene expression. AZT did not induce any deleterious impact on placental tissue structure. Furthermore, activation of chorionic villi by LPS for 24 h up-regulated IL-10 and TNF-alpha mRNA expression. Down-regulation of TNF-alpha mRNA could represent a mechanism through which AZT can decrease the risk of HIV-1 MTCT, in addition to its direct effect on HIV-1 replication.


Asunto(s)
Fármacos Anti-VIH/farmacología , Expresión Génica/efectos de los fármacos , Placenta/efectos de los fármacos , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Zidovudina/farmacología , Vellosidades Coriónicas/efectos de los fármacos , Regulación hacia Abajo , Femenino , Infecciones por VIH/prevención & control , VIH-1/efectos de los fármacos , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Lipopolisacáridos , Embarazo , ARN Mensajero/metabolismo , Técnicas de Cultivo de Tejidos
10.
Int J Gynaecol Obstet ; 92(2): 176-80, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16309684

RESUMEN

OBJECTIVE: To compare different methods of gestational age (GA) measurement for ensuring effective zidovudine (ZDV) prophylaxis to prevent mother-to-child transmission of HIV. METHODS: For 1398 HIV-infected women enrolled in a perinatal prevention trial, gestation durations were calculated based on GA estimated using ultrasound (US), date of last menstruation period (LMP), first fundal height (FH(1)), and a specific algorithm was developed to provide a "reference" GA. The performance of each GA estimate was evaluated by the percentage of women who would have received > or =8 weeks ZDV, if prophylaxis was initiated at 28 weeks. RESULTS: The performances of the algorithm, US, LMP, and FH(1) were 95.5%, 94.8%, 88.4%, and 83.7%, respectively. US and FH(1) were significantly better when estimated before and after 24 weeks, respectively. CONCLUSION: In situations where no US is available and LMP is not or imprecisely known, FH(1) can be used after 24 weeks to schedule ZDV initiation date.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Edad Gestacional , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Zidovudina/uso terapéutico , Fármacos Anti-VIH/administración & dosificación , Femenino , Humanos , Embarazo , Resultado del Embarazo , Tailandia , Factores de Tiempo , Zidovudina/administración & dosificación
11.
Cancer Res ; 42(2): 638-41, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7055808

RESUMEN

The aim of this work was to study whether an inhibitor of pluripotent stem cell (CFU-S) recruitment, which we have shown previously to be able to increase the number of CFU-S after a fractionated treatment with 1-beta-D-arabinofuranosylcytosine, could increase the survival of mice given injections of lethal doses of the same drug. Two protocols of 1-beta-D-arabinofuranosylcytosine treatment were used in two different mouse strains, which both killed the mice within a week. An inhibitor of CFU-S was prepared by dialysis from fetal calf marrow, and a first step of purification was made by chromatography on Sephadex G-10. When given injections 2 hr before the drug, the number of surviving mice was increased significantly with the dialysate; fractions separated by chromatography appeared to be more effective to increase the animal survival. These preliminary results indicate that a factor of low molecular weight (below M.W. 3500) extracted from fetal calf marrow is able to protect animals during 1-beta-D-arabinofuranosylcytosine treatment. The inhibitor seems to be specific for CFU-S, without any inhibiting effect on tumor cell kinetics in vitro. If the absence of species specificity found for higher to lower species is confirmed for the lower to the higher species, then this inhibitor could be an effective tool during cancer chemotherapy.


Asunto(s)
Citarabina/antagonistas & inhibidores , Células Madre Hematopoyéticas/fisiología , Animales , Médula Ósea/análisis , Médula Ósea/metabolismo , Bovinos , Cromatografía en Gel , Citarabina/toxicidad , Diálisis , Femenino , Ratones , Ratones Endogámicos C3H , Peso Molecular , Especificidad de la Especie
12.
Cancer Res ; 44(2): 493-7, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6141003

RESUMEN

Butoxamine, a beta 2-adrenergic blocking agent, which temporarily blocks the G1-S transition of human bone marrow granulocyte precursors in vitro, was used in vivo together with 1-beta-D-arabinofuranosylcytosine (ara-C) in mice. Butoxamine alone depressed the granulocyte labeling index and granulocyte-monocyte colony-forming Cell (GM-CFC) suicide rate at a dose of 3 micrograms/g body weight. A maximum effect was produced 6 to 12 hr after injection. Butoxamine administered 8 hr before an injection of ara-C modified the proportion of GM-CFC in S phase as compared with the number found after ara-C alone. After a series of five ara-C injections, administered at intervals of 16 hr, 70% of the treated mice died within 2 weeks, whereas only 42% of mice pretreated with butoxamine 7 to 9 hr before each ara-C injection died. This difference was due to the more rapid return to normal of GM-CFC numbers and an increase in the proportion of GM-CFC and granulocyte precursors in S phase in the butoxamine-pretreated animals. These findings suggest that butoxamine may have a potential use in protecting hematopoiesis during intensive chemotherapy for cancer.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Butoxamina/farmacología , Hematopoyesis/efectos de los fármacos , Interfase/efectos de los fármacos , Propanolaminas/farmacología , Animales , Citarabina/farmacología , Interacciones Farmacológicas , Granulocitos/efectos de los fármacos , Ratones , Factores de Tiempo
13.
Comput Methods Programs Biomed ; 77(2): 165-73, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15652638

RESUMEN

Comparing the reproducibility level of two devices with continuous outcome on a unique sample of subjects (each subject being assessed several times with both devices) comes down to compare two dependent intraclass correlation coefficients (ICCs). When planning such a reproducibility study, one has to specify both the number of subjects to be included and the number of replicates per subject associated to each device. We propose SAS and S-plus macros, which allow power calculations by implementing a simulation study where dependent ICCs are compared by means of a likelihood ratio-test.


Asunto(s)
Funciones de Verosimilitud , Reproducibilidad de los Resultados , Muestreo , Interpretación Estadística de Datos , Francia , Modelos Estadísticos
14.
Exp Hematol ; 17(2): 203-7, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2912743

RESUMEN

The purpose of this work was to investigate the long-term effects of high doses of cytosine arabinoside (Ara-C) on the pluripotent stem cell (spleen colony-forming units; CFU-S) compartment in mice. Studies were carried out on mice that survived the administration of repeated high doses of Ara-C (HDAra-C) with or without the injection of a partially purified CFU-S inhibitor or a bone marrow graft. The following features were examined 1, 1.5, and 5-7 months after treatment: CFU-S number, proliferative ability, and differentiation into different lineages. The results indicate that these parameters, which were severely disturbed soon after drug administration, returned to control levels within a month and remained unchanged as compared to age-matched controls for the following 6 months. Therefore, HDAra-C, given alone or with a CFU-S inhibitor or prior to bone marrow grafting, did not seem to induce long-lasting damage of the CFU-S compartment. However, our studies cannot eliminate the possibility of some residual stromal damage or some impairment of other properties of stem cells. It would be of importance to further clarify these points because HDAra-C are now used in the treatment of leukemias and prior to bone marrow transplantation.


Asunto(s)
Citarabina/toxicidad , Células Madre Hematopoyéticas/efectos de los fármacos , Bazo/efectos de los fármacos , Animales , Recuento de Células/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Citarabina/administración & dosificación , Esquema de Medicación , Femenino , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos CBA , Bazo/patología , Factores de Tiempo
15.
Exp Hematol ; 21(2): 311-8, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8425567

RESUMEN

Very long-lasting leukopenias and thrombocytopenias have been observed in patients submitted to transplantation of autologous bone marrow incubated in vitro with cyclophosphamide derivatives. With the aim of evaluating the contribution of in vitro exposure of bone marrow to mafosfamide (Asta-Z) and of in vivo chemotherapy given before bone marrow collection in these cytopenias, we designed a murine model of syngeneic bone marrow transplantation including treatment of donor and recipient mice with high doses of cyclophosphamide and in vitro exposure of the bone marrow transplant to Asta-Z. Blood platelets and leukocytes, medullary splenic colony forming unit (CFU-S), committed megacaryocytic (CFU-Meg) and granulomacrophagic (CFU-GM) precursor cell recovery was followed up to 56 days posttransplant. The data indicate that in vitro exposure of bone marrow to Asta-Z before reinfusion increases the delay in platelet recovery already induced by the chemotherapy given to donor mice and is specifically responsible for the prolongation of leukopenia. In recipient bone marrow, a synergy between the ablative effect of the in vitro treatment of bone marrow graft and the chemotherapy given to donors and recipients on CFU-S, CFU-Meg and CFU-GM was found.


Asunto(s)
Antineoplásicos/farmacología , Células de la Médula Ósea , Purgación de la Médula Ósea , Trasplante de Médula Ósea/métodos , Ciclofosfamida/análogos & derivados , Ciclofosfamida/farmacología , Hematopoyesis/fisiología , Animales , Plaquetas/citología , Médula Ósea/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Hematopoyesis/efectos de los fármacos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Leucocitos/citología , Masculino , Ratones , Ratones Endogámicos CBA , Modelos Biológicos , Trasplante Autólogo
16.
Exp Hematol ; 15(6): 631-5, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3297759

RESUMEN

We investigated the in vitro effect of ASTA-Z 7557 on the qualitative aspects of murine CFU-S differentiation, as assessed by the histological nature of day-9 colonies generated in the spleen of irradiated mice by bone marrow exposed to the drug at concentrations ranging from 0 to 150 micrograms/ml. The proportion of erythrocytic colonies declined linearly with the logarithm of the dose (a 22% decrease per log), whereas the granulocytic and megakaryocytic colony proportions increased linearly (a 10% increase per log for both cell lineages). This suggests a preferential channeling of CFU-S differentiation toward granulopoietic and megakaryocytic cell lineages as a consequence of the in vitro chemotherapy, and supports the hypothesis that some alteration of the qualitative potential of CFU-S to differentiate after in vitro purging of bone marrow with ASTA-Z 7557 takes place prior to autologous bone marrow transplantation.


Asunto(s)
Médula Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Ciclofosfamida/análogos & derivados , Células Madre/efectos de los fármacos , Animales , Médula Ósea/efectos de la radiación , Trasplante de Médula Ósea , Ciclofosfamida/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Granulocitos/citología , Hematopoyesis/efectos de los fármacos , Masculino , Megacariocitos/citología , Ratones , Ratones Endogámicos CBA , Ratones Endogámicos , Bazo/citología , Células Madre/citología
17.
Exp Hematol ; 11(4): 284-97, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6341077

RESUMEN

The aim of this work was to analyze quantitatively experimental data, which suggest that CFUS determination can be manipulated by external fibers. This hypothesis was based on the comparison of the ratio of erythroid to granulocytic spleen colonies generated by normal bone marrow exposed to factors released by either untreated or arabinoside cytosine treated mouse bone marrow. To investigate mechanisms able to produce this modification of spleen colony histology, statistical analysis was performed by testing three different schemes of evolution of the number of splenic colonies according to this histology from normal to treated groups. The total number of colonies per spleen is similar in both groups, but a significant increase of the number of erythroid colonies per spleen and a significant decrease of the number of granulocytic colonies are observed in the treated group as compared to control. Bias due to the used experimental technique are investigated but could not explain the observed differences. A unique mechanism acting on only one committed stem cell population does not fit the experimental data. Although other possible mechanisms are suggested, the experimental observations can be interpreted as the consequence of a shift of CFUS differentiation toward the erythroid pathway at the expense of at least the granulocytic lineage due to some humoral factors, secreted by treated mouse bone marrow.


Asunto(s)
Células de la Médula Ósea , Células Madre Hematopoyéticas/citología , Bazo/citología , Animales , Médula Ósea/efectos de los fármacos , Trasplante de Médula Ósea , Recuento de Células , Diferenciación Celular , Citarabina/farmacología , Eritrocitos/citología , Granulocitos/citología , Megacariocitos/citología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos CBA , Modelos Biológicos
18.
Exp Hematol ; 18(10): 1112-5, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2209766

RESUMEN

The purpose of this work was to study the effects of a tetrapeptide, acetyl-N-Ser-Asp-Lys-Pro (AcSDKP), an inhibitor of spleen colony-forming unit (CFU-S) entry into DNA synthesis, on human progenitor cells. Normal human mononuclear cells were incubated with concentrations of the synthetic tetrapeptide ranging from 10(-12) to 10(-7) M for 1.5 and 24 h and then plated in methylcellulose in the presence of human placenta-conditioned medium and recombinant human erythropoietin. The proportion of progenitors in DNA synthesis was determined by the thymidine suicide assay. Incubation with AcSDKP for 24 h leads to a significant inhibition of granulocyte-macrophage colony-forming unit (CFU-GM) and erythroid burst-forming unit (BFU-E) growth and in some cases of erythroid colony-forming unit (CFU-E) growth. The inhibition, which was never greater than 50%, was obtained with 10(-10)-10(-9) M AcSDKP, whereas no effect was seen at higher concentrations. The percentage of CFU-GM, BFU-E, and CFU-E in DNA synthesis was significantly reduced in five consecutive patients after incubation of cells for 24 h with inhibitory doses of the peptide, indicating that it is active on cycling cells. Therefore, these studies provide the first evidence that the tetrapeptide AcSDKP, originally obtained from bovine marrow and now chemically synthesized, is able to inhibit the in vitro growth of human progenitors and to decrease their proportion in cell cycle.


Asunto(s)
Células de la Médula Ósea , Células Precursoras Eritroides/citología , Células Madre Hematopoyéticas/citología , Oligopéptidos/farmacología , Secuencia de Aminoácidos , División Celular/efectos de los fármacos , Células Cultivadas , ADN/biosíntesis , Células Precursoras Eritroides/efectos de los fármacos , Células Precursoras Eritroides/metabolismo , Granulocitos/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Macrófagos/citología , Datos de Secuencia Molecular
19.
Exp Hematol ; 17(5): 429-32, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2653856

RESUMEN

Bone marrow purging with cyclophosphamide derivatives (Mafosfamide) requires the establishment of a defined experimental procedure for reliable leukemic cell destruction while sparing normal hematopoietic stem cells to ensure engraftment. We previously defined the granulocyte-macrophage colony-forming unit (CFU-GM) LD95 as being the maximum tolerable dose of drug to use. We now report, in 20 patients with acute non-lymphoblastic leukemia (n = 5), acute lymphoblastic leukemia (n = 5), chronic myelogenous leukemia (n = 5), and non-Hodgkin's lymphoma (n = 5), that the nature of the cells treated (i.e., buffy coat cells or mononuclear cells) significantly influences the accuracy of the LD95 determination, whereas other parameters such as hematocrit or nucleated cell concentration do not. We subsequently define the most reliable experimental procedure for in vitro purging with Mafosfamide: incubation of 2 x 10(7) buffy coat cells/ml with a hematocrit of 5%. We show that the wide individual susceptibility to the drug is not related to any incubation procedure. In a series of 163 patients with hematological malignancies, we confirm the large variation of sensitivity to the drug according to patient susceptibility and diagnosis. These data favor the adjustment of the dose of Mafosfamide on an individual basis, prior to bone marrow purging for autologous bone marrow transplantation.


Asunto(s)
Trasplante de Médula Ósea , Ciclofosfamida/análogos & derivados , Médula Ósea/efectos de los fármacos , Células de la Médula Ósea , Ciclofosfamida/farmacología , Granulocitos/efectos de los fármacos , Humanos , Técnicas In Vitro , Macrófagos/efectos de los fármacos , Células Madre/efectos de los fármacos
20.
Exp Hematol ; 14(5): 358-65, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3519263

RESUMEN

In 18 patients with non-Hodgkin's lymphomas or solid tumors treated with intensive chemotherapy and/or total-body irradiation followed by autologous bone marrow transplantation (ABMT), we assessed the value of granulocyte-macrophage progenitor cells (CFU-GM) monitoring to predict engraftment. We studied CFU-GM in cryopreserved marrow and attempted to settle whether detection of CFU-GM in vivo after ABMT has a predictive value on engraftment. Our data showed: The absence of linear correlation linking recovery of hematopoiesis to the dose of CFU-GM/kg infused. The existence of a CFU-GM threshold in respect to engraftment. Patients receiving doses of CFU-GM greater than 10(3)/kg had significantly faster recovery kinetics for hematopoiesis than did patients receiving doses below this threshold, with median recoveries to 0.5 and 1.0 X 10(9) neutrophils/liter, respectively, on days 14 and 15 versus days 29 and 31.5 (p less than 0.05 and p less than 0.02) and median recoveries to 1.0 and 2.5 X 10(9) leukocytes/liter respectively, on days 12.5 and 16 versus days 28 and 30.5 (p less than 0.05 and p less than 0.02). Considering the entire course of events during the first four weeks, we were able to show that white blood cell recovery was significantly faster in the group of patients receiving doses of CFU-GM greater than 10(3)/kg (p less than 0.001). Sequential studies of the reappearance of CFU-GM in marrow and peripheral blood indicated that the kinetics of CFU-GM recovery in vivo after ABMT predict engraftment. By day 7 after the graft, CFU-GM were already detectable in the marrow at a level of 10% of the dose infused for patients with optimal engraftment--median time to recovery to 1.0 and 2.5 X 10(9) leukocytes/liter and 1.0 X 10(9) neutrophils/liter on days 11, 15, and 14.5 versus days 18, 23, and 23 (p less than 0.02, less than 0.05, and less than 0.05), respectively after. On day 10 after ABMT, a 15% CFU-GM level in bone marrow confirmed engraftment, with a significant correlation of all parameters studied--1.0 and 2.5 X 10(9) leukocytes/liter (p less than 0.02 and less than 0.01), 0.5 and 1.0 X 10(9) neutrophils/liter (p less than 0.05), 50.0 and 100.0 X 10(9) platelets/liter (p less than 0.05). On day 14, a 50% CFU-GM level was reached in all patients with optimal engraftment; p less than 0.01 on 1.0, and 2.5 X 10(9) leukocytes on 0.5 and 1.0 X 10(9) neutrophils/liter. The detection of circulating CFU-GM in the blood by day 10 or 14 indicated engraftment.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Trasplante de Médula Ósea , Adolescente , Adulto , Frío , Ensayo de Unidades Formadoras de Colonias , Estudios de Evaluación como Asunto , Femenino , Granulocitos/citología , Humanos , Macrófagos/citología , Masculino , Persona de Mediana Edad , Células Madre/citología , Trasplante Autólogo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA