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1.
Biology (Basel) ; 12(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36671746

RESUMEN

Postpartum hemorrhage (PPH) is one of the leading causes of maternal morbidity worldwide. This study aimed to develop and validate a predictive model for PPH after vaginal deliveries, based on routinely available clinical and biological data. The derivation monocentric cohort included pregnant women with vaginal delivery at Brest University Hospital (France) between April 2013 and May 2015. Immediate PPH was defined as a blood loss of ≥500 mL in the first 24 h after delivery and measured with a graduated collector bag. A logistic model, using a combination of multiple imputation and variable selection with bootstrap, was used to construct a predictive model and a score for PPH. An external validation was performed on a prospective cohort of women who delivered between 2015 and 2019 at Brest University Hospital. Among 2742 deliveries, PPH occurred in 141 (5.1%) women. Eight factors were independently associated with PPH: pre-eclampsia (aOR 6.25, 95% CI 2.35−16.65), antepartum bleeding (aOR 2.36, 95% CI 1.43−3.91), multiple pregnancy (aOR 3.24, 95% CI 1.52−6.92), labor duration ≥ 8 h (aOR 1.81, 95% CI 1.20−2.73), macrosomia (aOR 2.33, 95% CI 1.36−4.00), episiotomy (aOR 2.02, 95% CI 1.40−2.93), platelet count < 150 Giga/L (aOR 2.59, 95% CI 1.47−4.55) and aPTT ratio ≥ 1.1 (aOR 2.01, 95% CI 1.25−3.23). The derived predictive score, ranging from 0 to 10 (woman at risk if score ≥ 1), demonstrated a good discriminant power (AUROC 0.69; 95% CI 0.65−0.74) and calibration. The external validation cohort was composed of 3061 vaginal deliveries. The predictive score on this independent cohort showed an acceptable ability to discriminate (AUROC 0.66; 95% CI 0.62−0.70). We derived and validated a robust predictive model identifying women at risk for PPH using in-depth statistical methodology. This score has the potential to improve the care of pregnant women and to take preventive actions on them.

2.
Blood ; 123(9): 1372-83, 2014 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-24398328

RESUMEN

The main molecular basis of essential thrombocythemia and hereditary thrombocytosis is acquired, and germ-line-activating mutations affect the thrombopoietin signaling axis. We have identified 2 families with hereditary thrombocytosis presenting novel heterozygous germ-line mutations of JAK2. One family carries the JAK2 R867Q mutation located in the kinase domain, whereas the other presents 2 JAK2 mutations, S755R/R938Q, located in cis in both the pseudokinase and kinase domains. Expression of Janus kinase 2 (JAK2) R867Q and S755R/R938Q induced spontaneous growth of Ba/F3-thrombopoietin receptor (MPL) but not of Ba/F3-human receptor of erythropoietin cells. Interestingly, both Ba/F3-MPL cells expressing the mutants and platelets from patients displayed thrombopoietin-independent phosphorylation of signal transducer and activator of transcription 1. The JAK2 R867Q and S755R/R938Q proteins had significantly longer half-lives compared with JAK2 V617F. The longer half-lives correlated with increased binding to the heat shock protein 90 (HSP90) chaperone and with higher MPL cell-surface expression. Moreover, these mutants were less sensitive to JAK2 and HSP90 inhibitors than JAK2 V617F. Our results suggest that the mutations in the kinase domain of JAK2 may confer a weak activation of signaling specifically dependent on MPL while inducing a decreased sensitivity to clinically available JAK2 inhibitors.


Asunto(s)
Resistencia a Medicamentos/genética , Mutación de Línea Germinal , Janus Quinasa 2/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Trombocitosis/tratamiento farmacológico , Trombocitosis/genética , Adolescente , Adulto , Anciano , Animales , Células Cultivadas , Femenino , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/química , Masculino , Ratones , Persona de Mediana Edad , Linaje , Estructura Terciaria de Proteína/genética , Adulto Joven
3.
PLoS One ; 8(9): e74728, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24069336

RESUMEN

Inherited thrombocytopenia is a heterogeneous group of disorders characterized by a reduced number of blood platelets. Despite the identification of nearly 20 causative genes in the past decade, approximately half of all subjects with inherited thrombocytopenia still remain unexplained in terms of the underlying pathogenic mechanisms. Here we report a six-generation French pedigree with an autosomal dominant mode of inheritance and the identification of its genetic basis. Of the 55 subjects available for analysis, 26 were diagnosed with isolated macrothrombocytopenia. Genome-wide linkage analysis mapped a 10.9 Mb locus to chromosome 14 (14q22) with a LOD score of 7.6. Candidate gene analysis complemented by targeted next-generation sequencing identified a missense mutation (c.137GA; p.Arg46Gln) in the alpha-actinin 1 gene (ACTN1) that segregated with macrothrombocytopenia in this large pedigree. The missense mutation occurred within actin-binding domain of alpha-actinin 1, a functionally critical domain that crosslinks actin filaments into bundles. The evaluation of cultured mutation-harboring megakaryocytes by electron microscopy and the immunofluorescence examination of transfected COS-7 cells suggested that the mutation causes disorganization of the cellular cytoplasm. Our study concurred with a recently published whole-exome sequence analysis of six small Japanese families with congenital macrothrombocytopenia, adding ACTN1 to the growing list of thrombocytopenia genes.


Asunto(s)
Actinina/genética , Plaquetas/patología , Genes Dominantes , Mutación Missense , Trombocitopenia/genética , Trombocitopenia/patología , Actinina/metabolismo , Adolescente , Adulto , Anciano , Animales , Plaquetas/ultraestructura , Médula Ósea/patología , Células COS , Chlorocebus aethiops , Familia , Femenino , Francia , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Linaje , Agregación Plaquetaria , Recuento de Plaquetas , Análisis de Secuencia de ADN , Trombocitopenia/metabolismo , Adulto Joven
4.
Br J Haematol ; 162(6): 783-91, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23848933

RESUMEN

Myeloproliferative neoplasm-related myelofibrosis is associated with cytopenic or proliferative phases, splenomegaly and constitutional symptoms. Few effective treatments are available and small series suggested that interferon could be an option for myelofibrosis therapy. We performed a retrospective study of pegylated-interferon α-2a (Peg-IFNα-2a) therapy in myelofibrosis. Sixty-two patients treated with Peg-IFNα-2a at 17 French and Belgian centres were included. Responses were determined based on the criteria established by the International Working Group for Myelofibrosis Research and Treatment. Mean follow-up was 26 months. Sixteen of 25 anaemic patients (64%) (eight concomitantly receiving recombinant erythropoietin) achieved a complete response and transfusion-independence was obtained in 5/13 patients (38·5%). Constitutional symptoms resolved in 82% of patients. All five leucopenic patients normalized their leucocyte counts, whereas a normal platelet count was obtained in 5/8 thrombocytopenic patients. Splenomegaly was reduced in 46·5% of patients, and complete resolution of thrombocytosis and leucocytosis were observed in 82·8% and 68·8% of patients, respectively. Side effects (mostly haematological) were mainly of grade 1-2. The only factor independently associated with treatment failure was a spleen enlargement of more than 6 cm below the costal margin. In conclusion, Peg-IFNα-2a induced high response rates with acceptable toxicity in a large proportion of patients with primary and secondary myelofibrosis, especially in early phases.


Asunto(s)
Interferón-alfa/efectos adversos , Interferón-alfa/uso terapéutico , Polietilenglicoles/efectos adversos , Polietilenglicoles/uso terapéutico , Mielofibrosis Primaria/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Mielofibrosis Primaria/patología , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
5.
Haematologica ; 98(6): 881-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23445876

RESUMEN

Romiplostim and eltrombopag, the first thrombopoietic receptor-agonists with demonstrated efficacy against immune thrombocytopenia in prospective controlled studies, were recently authorized in most countries for adults with chronic immune thrombocytopenia. So far, no data are available about the potential contribution of switching from romiplostim to eltrombopag or vice versa in terms of efficacy or tolerance. Efficacies and tolerance profiles were evaluated for 46 patients who sequentially received both drugs, switching from one to the other. The reasons for switching were: lack of efficacy for 23 patients, platelet-count fluctuations for 11, side effects for 4, and 8 patients' preferences. For 50-80% of the patients, switching from romiplostim to eltrombopag or eltrombopag to romiplostim effectively impacted the platelet count, with fluctuations disappearing in 54% and side effects resolved in 100%. In 80% of the patients, the 2 thrombopoietic receptor-agonists achieved similar response patterns. Our results confirmed that switching from one thrombopoietic receptor-agonist to the other could be beneficial in clinical practice for patients with severe chronic immune thrombopenia who failed to respond or experienced adverse events to the first. (Clinical Trials.gov identifier: NCT01618734).


Asunto(s)
Benzoatos/uso terapéutico , Hidrazinas/uso terapéutico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Pirazoles/uso terapéutico , Receptores Fc/uso terapéutico , Receptores de Trombopoyetina/agonistas , Proteínas Recombinantes de Fusión/uso terapéutico , Trombopoyetina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Benzoatos/administración & dosificación , Benzoatos/efectos adversos , Sustitución de Medicamentos , Femenino , Humanos , Hidrazinas/administración & dosificación , Hidrazinas/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Recuento de Plaquetas , Pirazoles/administración & dosificación , Pirazoles/efectos adversos , Receptores Fc/administración & dosificación , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/efectos adversos , Estudios Retrospectivos , Trombopoyetina/administración & dosificación , Trombopoyetina/efectos adversos , Resultado del Tratamiento
6.
Thromb Haemost ; 107(1): 44-50, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22159456

RESUMEN

Constitutional deficiency in factor XI (FXI) is a rare bleeding disorder in the general population, with the exception of Ashkenazi Jews. During the last decade, the detection of FXI-deficient patients has shifted from clinical screening identifying mostly severe bleeders to biological screening combining findings of prolonged activated partial thromboplastin time and FXI coagulation activity (FXI:C) below 50 U/dl. The goal of this study was to determine the molecular basis of FXI deficiency in western Brittany, France. Over the course of four years, we detected 98 FXI-deficient patients through biological screening, and 44 patients agreed to participate in this study corresponding to 25 index cases. We developed an efficient mutation detection strategy (combining direct sequencing and QFM-PCR to search for heterozygous rearrangements in a routine setting) that detected F11 mutations in 24 out of the 25 index cases. An unexpected allelic heterogeneity was found, with 14 different single point mutations being detected, among which nine are new. Moreover, a large heterozygous deletion of the entire F11 gene was detected, and was then further defined using a CGH array as a 4q34.2 telomeric deletion of 7 Mb containing 77 genes. We propose that the observed recurrent mutations may be considered as genetic tags of a population. This study highlights the importance of screening for large deletions in molecular studies of F11 .


Asunto(s)
Deficiencia del Factor XI/epidemiología , Deficiencia del Factor XI/genética , Mutación , Adolescente , Adulto , Anciano , Alelos , Coagulación Sanguínea , Deleción Cromosómica , Cromosomas Humanos Par 4/genética , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Exones , Femenino , Francia , Reordenamiento Génico , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Epidemiología Molecular/métodos , Telómero/ultraestructura
7.
Br J Haematol ; 156(2): 245-51, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22098495

RESUMEN

Bleeding risk is not predictable in patients with factor XI (FXI; F11) deficiency. In this prospective study, our objectives were to determine the biological determinants for bleeding risk in patients with heterozygous FXI deficiency. Patients were classified as either bleeding patients or non-bleeding patients by calculating the bleeding score (BS) described for von Willebrand disease. Primary haemostasis, thrombin generation, thromboelastometry, procoagulant proteins, inhibitors, fibrinolysis, and F11 gene mutations were compared between bleeding and non-bleeding patients. Thirty-nine patients were included. BS significantly correlated with clinical assessment (P=0·001), and a score over 3 discriminated between bleeding (n=15) and non-bleeding (n=24) patients (P=0·034). Despite normal values, von Willebrand factor (VWF) and thrombomodulin (TM) plasma levels were significantly lower in bleeding patients than non-bleeding patients [ristocetin cofactor activity (VWF:RCo)=80·6±29·7 iu/dl and 101·8±29·5iu/dl respectively, P=0·043; and VWF antigen (VWF:Ag)=84·0±28·0 iu/dl and 106·3±36·1 iu/dl respectively, P=0·035; and TM=17·7±11·7ng/ml and 23·6±9·7ng/ml respectively, P=0·043]. When considering BS as a continuous variable, only VWF:RCo remained significant (P=0·042), which accounted for 11% of the variability in BS.


Asunto(s)
Coagulación Sanguínea/genética , Deficiencia del Factor XI/sangre , Hemorragia/sangre , Adolescente , Adulto , Anciano , Niño , Factor VIII/genética , Deficiencia del Factor XI/genética , Femenino , Predisposición Genética a la Enfermedad , Hemorragia/genética , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
8.
Haematologica ; 96(8): 1226-30, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21459789

RESUMEN

Analyses of site-directed fibrinogen mutants expressed in several recombinant models have previously shown that both inter- and intra-chain disulfide bonds are critical for fibrinogen assembly and secretion. Four naturally occurring mutations on AαCys36 and AαCys45 residues are reported here to be associated with decreased fibrinogen levels. This confirms the main role of the AαCys36-BßCys65 and AαCys45-γCys23 disulfide bonds in reaching a normal fibrinogen plasma level. Decreased coagulant/antigen ratios indicate abnormal species secretion in heterozygous subjects which varies between individuals. However, in contrast to overexpression in experimental models, disruption of the AαCys36-BßCys65 disulfide bond did not result in the appearance of Aα-Bß-γ moieties in vivo. A 188 kDa molecule reacting only with anti Aα and anti Bß chains was found in the plasma of the AαCys45Tyr variant. Heterozygous carriers of Aα chain mutations usually have normal fibrinogen levels, in contrast to the AαCys36Gly, AαCys36Arg and AαCys45Tyr variants that are shown here to cause hypofibrinogenemia.


Asunto(s)
Disulfuros/química , Fibrinógeno/química , Adulto , Sustitución de Aminoácidos , Disulfuros/metabolismo , Femenino , Fibrinógeno/genética , Fibrinógeno/metabolismo , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación/genética , Polimorfismo Genético , Conformación Proteica
9.
Thromb Res ; 126(3): 238-42, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20656333

RESUMEN

Microparticles (MPs) are membrane fragments ranging in size from 0.1 to 1 microm, and are considered as biomarkers reflecting prothrombotic state in many clinical diseases. The clinical course of myeloproliferative neoplasms (MPN) being frequently complicated by thrombotic events, we determined the MPs activity, i.e. circulating procoagulant activity (CPA), in polycythemia vera (PV) and essential thrombocythemia (ET) patients. To evaluate the influence of MPs on the coagulation, a thrombin generation test was realized in the absence and presence of thrombomodulin (TM). Compared with controls, patients had a higher CPA (24.0+/-9.0 vs 10.6+/-4.4 nM, p<0.001), which was associated with a lower inhibition of the thrombin generation in the presence of TM (20.1+/-9.5% vs 28.4+/-11.8%, p<0.001), compatible with a low sensitivity to TM. This sensitivity was influenced by the JAK2V617F mutational status, homozygous patients presenting the lowest inhibition rate of the thrombin generation. Filtration through a 0.22 microm membrane increased the sensitivity to TM in plasma, suggesting an influence of MPs in the "TM-resistance" observed in patients. Moreover, MPN patients receiving antiplatelet and/or cytoreductive therapies, our study suggests that CPA might be influenced by cytoreductive therapy. In conclusion, our data evidence in MPN patients the occurrence of an acquired "TM-resistance" partly determined by circulating microparticles. This TM-resistance might contribute to the hypercoagulable state observed in MPN patients, but the predictive value of the "TM-resistance" for thrombosis had not been evaluated.


Asunto(s)
Coagulación Sanguínea , Micropartículas Derivadas de Células/metabolismo , Policitemia Vera/complicaciones , Trombina/metabolismo , Trombocitemia Esencial/complicaciones , Trombosis/etiología , Adulto , Anciano , Anciano de 80 o más Años , Pruebas de Coagulación Sanguínea , Estudios de Casos y Controles , Femenino , Francia , Predisposición Genética a la Enfermedad , Humanos , Janus Quinasa 2/genética , Masculino , Persona de Mediana Edad , Mutación , Fenotipo , Inhibidores de Agregación Plaquetaria/uso terapéutico , Policitemia Vera/sangre , Policitemia Vera/tratamiento farmacológico , Policitemia Vera/genética , Medición de Riesgo , Factores de Riesgo , Trombocitemia Esencial/sangre , Trombocitemia Esencial/tratamiento farmacológico , Trombocitemia Esencial/genética , Trombomodulina/metabolismo , Trombosis/sangre , Trombosis/genética , Trombosis/prevención & control , Regulación hacia Arriba
11.
Thromb Haemost ; 99(4): 767-73, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18392335

RESUMEN

The thrombin generation test is used to study coagulation in patients with haemorrhagic diseases or with high thrombotic risk. To our knowledge, this is the first study investigating the relative influence of coagulation factors on thrombin generation in plasma. The aim was to investigate the influence of coagulant factors, anticoagulant factors, and tissue factor (TF) on three parameters: endogenous thrombin potential (ETP), peak thrombin concentration, and lag time for the appearance of thrombin. At a low TF concentration, all factors except factor XI influenced thrombin generation. At a high TF concentration, only the factors of the extrinsic pathway exerted an influence. ETP and peak thrombin were linearly correlated to factor II concentration. Factor V and factor VII effects increased hyperbolically with factor concentration. The influence of factor X on thrombin generation depended on TF concentration. In the absence of factor VIII and factor IX, ETP fell to 60-70% of the normal when peak thrombin fell to 25-30% of the normal. Fibrinogen concentration influenced ETP and peak thrombin and decreasing fibrinogen levels shortened the lag time. As expected, decreasing antithrombin concentration caused dramatic increases in thrombin generation. Protein S prolonged the lag time, especially at a low TF concentration. No effect of protein C was observed, likely due to the absence of thrombomodulin. The thrombin generation test was more sensitive to factor deficiencies at low than at high TF concentration. ETP was not the most critical parameter for studying coagulation factor deficiencies. Instead, peak thrombin was the most sensitive parameter.


Asunto(s)
Factores de Coagulación Sanguínea/metabolismo , Pruebas de Coagulación Sanguínea/métodos , Trombina/biosíntesis , Tromboplastina/metabolismo , Pruebas de Coagulación Sanguínea/estadística & datos numéricos , Trastornos de las Proteínas de Coagulación/sangre , Hemorragia/sangre , Humanos , Sensibilidad y Especificidad , Tromboplastina/deficiencia , Trombosis/sangre
12.
J Am Coll Cardiol ; 51(3): 256-60, 2008 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-18206732

RESUMEN

OBJECTIVES: This trial sought to assess the influence of omeprazole on clopidogrel efficacy. BACKGROUND: Clopidogrel has proved its benefit in the treatment of atherothrombotic diseases. In a previous observational study, we found clopidogrel activity on platelets, tested by vasodilator-stimulated phosphoprotein (VASP) phosphorylation, to be diminished in patients receiving proton pump inhibitor (PPI) treatment. METHODS: In this double-blind placebo-controlled trial, all consecutive patients undergoing coronary artery stent implantation received aspirin (75 mg/day) and clopidogrel (loading dose, followed by 75 mg/day) and were randomized to receive either associated omeprazole (20 mg/day) or placebo for 7 days. Clopidogrel effect was tested on days 1 and 7 in both groups by measuring platelet phosphorylated-VASP expressed as a platelet reactivity index (PRI). Our main end point compared PRI value at the 7-day treatment period in the 2 groups. RESULTS: Data for 124 patients were analyzed. On day 1, mean PRI was 83.2% (standard deviation [SD] 5.6) and 83.9% (SD 4.6), respectively, in the placebo and omeprazole groups (p = NS), and on day 7, 39.8% (SD 15.4) and 51.4% (SD 16.4), respectively (p < 0.0001). RESULTS: Omeprazole significantly decreased clopidogrel inhibitory effect on platelet P2Y12 as assessed by VASP phosphorylation test. Aspirin-clopidogrel antiplatelet dual therapy is widely prescribed worldwide, with PPIs frequently associated to prevent gastrointestinal bleeding. The clinical impact of these results remains uncertain but merits further investigation.


Asunto(s)
Omeprazol/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Inhibidores de la Bomba de Protones/farmacología , Ticlopidina/análogos & derivados , Anciano , Angioplastia Coronaria con Balón , Moléculas de Adhesión Celular/metabolismo , Clopidogrel , Método Doble Ciego , Antagonismo de Drogas , Quimioterapia Combinada , Femenino , Humanos , Masculino , Proteínas de Microfilamentos/metabolismo , Persona de Mediana Edad , Infarto del Miocardio/terapia , Omeprazol/uso terapéutico , Fosfoproteínas/metabolismo , Fosforilación , Agregación Plaquetaria/efectos de los fármacos , Estudios Prospectivos , Inhibidores de la Bomba de Protones/uso terapéutico , Stents , Ticlopidina/antagonistas & inhibidores , Ticlopidina/uso terapéutico
13.
Thromb Haemost ; 99(1): 223-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18217158

RESUMEN

The thrombin generation test appears to be a highly sensitive and specific test in the detection of thrombophilia in patients with venous thromboembolism. We aimed to determine the accuracy of the thrombin generation test to detect factor V Leiden and/or other prothrombotic states in first-degree relatives of patients with venous thromboembolism and factor V Leiden. Sixty-two first-degree relatives of 21 index cases were tested for factor V Leiden, the G20210A prothrombin gene mutation and thrombin generation. Information about oestrogen therapy and previous VTE was also collected. The normalized Thrombomodulin sensitivity ratio (n-TMsr) was defined as the ratio of endogenous thrombin potential determined in the presence and absence of thrombomodulin which was normalized against the same ratio determined in normal control plasma. The mean n-TMsr was 1.37 (+/- 0.33) in the 45 relatives with one or more prothrombotic state (factor V Leiden, G20210A prothrombin mutation, oestrogen therapy or hormonal therapy) and 1.02 (+/- 0.34) in the 17 relatives without prothrombotic state (p = 0.001). The positive predictive value was 90.3 (95%CI, 73.1-97.4). In relatives with an abnormal n-TMsr, the adjusted odds ratio for having a prothrombotic state was 8.3 (95%CI, 1.9-36.9) and the adjusted odds ratio for having the factor V Leiden was 14.3 (95%CI, 2.9-71.2). An abnormal thrombin generation test appears highly predictive for having factor V Leiden and/or other prothrombotic states in first-degree relatives of patients with venous thromboembolism and factor V Leiden.


Asunto(s)
Pruebas de Coagulación Sanguínea/métodos , Factor V/genética , Mutación , Trombina/metabolismo , Trombofilia/diagnóstico , Tromboembolia Venosa/etiología , Adulto , Anciano , Anticonceptivos Hormonales Orales/efectos adversos , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Linaje , Proyectos Piloto , Valor Predictivo de las Pruebas , Protrombina/genética , Medición de Riesgo , Factores de Riesgo , Trombomodulina/metabolismo , Trombofilia/sangre , Trombofilia/inducido químicamente , Trombofilia/complicaciones , Trombofilia/genética , Tromboembolia Venosa/sangre , Tromboembolia Venosa/inducido químicamente , Tromboembolia Venosa/genética
14.
Cancer Genet Cytogenet ; 175(2): 125-31, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17556068

RESUMEN

Dicentric chromosomes have often been observed in complex karyotypes in previously reported studies of therapy-related myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Fluorescence in situ hybridization (FISH) has now made the characterization of these rearrangements much easier. Dicentric and tricentric chromosomes were identified in 21 patients (9 MDS and 12 AML) among the 133 consecutive MDS/AML patients (17%) who had a structural or numerical aberration of chromosome 5 using conventional cytogenetic analysis. One third (7/21) of the patients had received alkylating drugs for a previously diagnosed cancer or chronic myeloproliferative disease. Loss of 5q material was identified in all 21 patients. One copy of the EGR1 (5q31) or the CSF1R (5q33 approximately q34) genes was lost in 20 of the 21 patients. Dicentric and tricentric chromosomes involving chromosome 5 are frequently observed in complex karyotypes among patients with de novo or therapy-related MDS/AML. They lead to deletions of various parts of the long arm of chromosome 5.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 5/genética , Leucemia Mieloide/genética , Síndromes Mielodisplásicos/genética , Adulto , Anciano , Anciano de 80 o más Años , Deleción Cromosómica , Femenino , Humanos , Cariotipificación , Leucemia Mieloide Aguda/genética , Masculino , Persona de Mediana Edad
15.
Thromb Haemost ; 96(6): 744-9, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17139368

RESUMEN

The factor V Leiden (FVL) mutation, a genetic abnormality with an autosomal mode of inheritance, is associated with an increased risk of venous thromboembolism (VTE). We aimed to determine the annual incidence of VTE in first-degree relatives of patients with VTE and FVL and to identify factors in patients and the relatives that influence this incidence. In this retrospective and prospective cohort study, the incidence of objectively diagnosed first episodes of VTE was assessed in 553 first-degree relatives of 161 patients with acute VTE and FVL. The annual incidence of VTE was 0.43% (95% CI, 0.3 to 0.56) with FVL and 0.17% (95% CI, 0.07 to 0.27) without FVL (relative risk of 2.5,95% CI, 1.3 to 4.7). A majority (70%) of episodes of VTE were provoked, and this proportion was similar with and without FVL. A larger proportion of VTE was provoked in women (83%) that in men (33%), with the difference accounted for by pregnancy and use of oral contraceptives. The proportion of pregnancies complicated by VTE was 3.9% (95% CI, 2.0-5.8) with FVL and 1.4% (95% CI, 0.04-2.7) without FVL. FVL is associated with a two- to threefold increase in VTE in first-degree relatives of patients with VTE. No subgroup of relatives was identified who require more than routine prophylaxis because of a particularly high risk of VTE.


Asunto(s)
Factor V/genética , Predisposición Genética a la Enfermedad , Complicaciones Cardiovasculares del Embarazo/epidemiología , Embolia Pulmonar/epidemiología , Trombosis de la Vena/epidemiología , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Anciano , Envejecimiento , Estudios de Cohortes , Anticonceptivos Orales/efectos adversos , Femenino , Francia/epidemiología , Genotipo , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Linaje , Embarazo , Complicaciones Cardiovasculares del Embarazo/genética , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Embolia Pulmonar/etiología , Embolia Pulmonar/genética , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Caracteres Sexuales , Distribución por Sexo , Factores Sexuales , Trombosis de la Vena/etiología , Trombosis de la Vena/genética
16.
Haematologica ; 91(10): 1418-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16963399

RESUMEN

Beta-thalassemia mutations were determined in ten Breton probands using a reverse-hybridization method or denaturing gradient gel electrophoresis and sequencing. Six different mutations were found: three from the Mediterranean area and three rare. Mutations responsible for beta-thalassemia in Brittany are quite heterogeneous. The mutation in the initiation codon ATG-->ACG was found in four families and may result from an ancient founder effect, as suggested by the haplotype analysis.


Asunto(s)
Mutación , Grupos de Población/genética , Talasemia beta/genética , Femenino , Francia , Haplotipos/genética , Humanos , Masculino , Región Mediterránea/epidemiología , Talasemia beta/epidemiología
17.
Haematologica ; 91(8): 1027-32, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16885042

RESUMEN

BACKGROUND AND OBJECTIVES: In non-randomized studies, thalidomide appeared to be effective in myeloid metaplasia with myelofibrosis (MMM). We compared thalidomide to placebo for treatment of anemia in MMM. DESIGN AND METHODS: A prospective phase II B, randomized double-blind multicenter trial comparing thalidomide 400 mg/d with placebo for 180 days was conducted in 52 anemic patients (hemoglobin pounds Sterling 9 g/dL or transfused). The main outcome measure was a 2 g/L increase in hemoglobin or 20% reduction in transfusions. RESULTS: In the thalidomide group only 10 patients completed 6 months of treatment. At 180 days, in an intention-to-treat analysis, no difference was observed between the thalidomide and placebo groups as regards improvement of hemoglobin levels (one patient in each group) or reduction of red blood cell transfusions (three vs five patients, respectively). The spleen size, determined by ultrasonography, increased significantly less in the thalidomide group than in the placebo group (p < 0.05). Thalidomide had no apparent benefit on the Dupriez score, the severity score, survival, death, or any other clinical or biological parameter. Somnolence, gastro-intestinal signs, weight gain, and edema were significantly more frequent in the thalidomide group. Outpatient discontinuation of thalidomide was significantly correlated with a high severity score > 4 (odds ratio, OR = 16; p < 0.01), and g-glutamyl transferase levels > 40 IU/L (OR = 12; p < 0.05). INTERPRETATION AND CONCLUSIONS: Thalidomide (200-400 mg/d) does not demonstrate substantial efficacy in anemic MMM patients. The natural history of disease in the placebo group revealed spontaneous periods of remission of anemia. Tolerance of thalidomide was significantly correlated wih the severity and liver involvement of the disease.


Asunto(s)
Mielofibrosis Primaria/complicaciones , Mielofibrosis Primaria/tratamiento farmacológico , Talidomida/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Método Doble Ciego , Francia , Humanos , Placebos , Reproducibilidad de los Resultados , Proyectos de Investigación , Talidomida/toxicidad
18.
Anticancer Res ; 26(2A): 953-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16619492

RESUMEN

Multiple myeloma (MM) is a malignancy of the terminally-differentiated B cells and accounts for 10% of all hematological malignancies. Chromosome 1 aberrations are frequently described, the short arm being preferentially involved in deletions and the long arm in gains. The abnormalities were identified in the bone marrow of 37 MM patients by conventional cytogenetics. Fluorescence in situ hybridization (FISH) was used to confirm the presence of the abnormalities and to better characterize them. Chromosome 1 abnormalities were grouped into 4 categories: balanced translocations, deletions, amplifications and jumping translocations (JT). Breakpoints involved in balanced translocations were randomly distributed. The smallest region of overlap for deletions was 1p11 --> 1p21 (present in 27% of the patients) and for gains 1q31 --> 1qter (present in 54% of the patients). The whole long arm was found to be the donor segment for the majority of patients with JT, the most frequent recipients being chromosomes 16 and 19. Our results share some similarities with those obtained for 143 published patients studied by FISH. Band 1p21 was found to be frequently deleted, leading to the assumption that a 1p deletion could lead to hemizygosity of at least 1 tumor suppressor gene. Two regions of 1q showed preferential gains: q12 to q22 and q31 to q42; these amplifications could induce the overexpression of 1 or more oncogenes. In conclusion, our results confirm that chromosome 1 abnormalities play an important role in the pathogenesis of multiple myeloma.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 1/genética , Mieloma Múltiple/genética , Bandeo Cromosómico , Deleción Cromosómica , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Translocación Genética
20.
Anticancer Res ; 25(5): 3179-82, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16101124

RESUMEN

Rearrangements involving the IGH gene have been identified in about 50% of non-Hodgkin's B-cell lymphomas (NHL) and correlated to clinical relevant subgroups. However, the detection rate varied greatly with the technique used. The incidence of IGH rearrangements was analyzed using several fluorescence in situ hybridization (FISH) techniques on metaphases obtained from 57 patients with nodal NHL. An IGH rearrangement was identified in 42 cases (73.7%). A t(14;18)(q32;q21) was found in 17 of the 20 follicular lymphomas (85%) studied and a t(11;14)(q13;q32) in 10 of the 11 mantle cell lymphomas (91%). IGH rearrangements were identified in 12 of the 26 diffuse large B-cell lymphomas (46%), including 5 t(14;18)(q32;q21) and 2 t(3;14)(q27;q32). Conventional cytogenetics was uninformative in several cases. However, the complemented analysis using Multi-FISH and/or chromosomal whole paint enabled the characterization of complex IGH translocations in follicular lymphomas and mantle cell lymphomas and the identification of all the chromosomal partners involved in the IGH rearrangement in diffuse large B-cell lymphomas. This study shows the interest of using metaphase FISH in addition to conventional cytogenetics. Following banding techniques, FISH with the IGH dual color probe could be the first approach in NHL, after which chromosome painting and M-FISH could be used to identify the chromosomal partner involved in the IGH rearrangement.


Asunto(s)
Reordenamiento Génico , Cadenas Pesadas de Inmunoglobulina/genética , Linfoma de Células B/genética , Cromosomas Humanos Par 14/genética , Cromosomas Humanos Par 18/genética , Humanos , Hibridación Fluorescente in Situ , Linfoma de Células B/inmunología , Linfoma Folicular/genética , Linfoma Folicular/inmunología , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células del Manto/genética , Linfoma de Células del Manto/inmunología , Translocación Genética
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