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1.
Nat Med ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830994

RESUMEN

CD38-targeting immunotherapy is approved in combination with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma (NDMM) that are transplant ineligible (TI) and is considered the best standard of care (SOC). To improve current SOC, we evaluated the added value of weekly bortezomib (V) to isatuximab plus lenalidomide and dexamethasone (IsaRd versus Isa-VRd). This Intergroupe Francophone of Myeloma phase 3 study randomized 270 patients with NDMM that were TI, aged 65-79 years, to IsaRd versus Isa-VRd arms. The primary endpoint was a minimal residual disease (MRD) negativity rate at 10-5 by next-generation sequencing at 18 months from randomization. Key secondary endpoints included response rates, MRD assessment rates, survival and safety. The 18-month MRD negativity rates at 10-5 were reported in 35 patients (26%, 95% confidence interval (CI) 19-34) in IsaRd versus 71 (53%, 95% CI 44-61) in Isa-VRd (odds ratio for MRD negativity 3.16, 95% CI 1.89-5.28, P < 0.0001). The MRD benefit was consistent across subgroups at 10-5 and 10-6, and was already observed at month 12. The proportion of patients with complete response or better at 18 months was higher with Isa-VRd (58% versus 33%; P < 0.0001), as was the proportion of MRD negativity and complete response or better (37% versus 17%; P = 0.0003). At a median follow-up of 23.5 months, no difference was observed for survival times (immature data). The addition of weekly bortezomib did not significantly affect the relative dose intensity of IsaRd. Isa-VRd significantly increased MRD endpoints, including the 18-month negativity rate at 10-5, the primary endpoint, compared with IsaRd. This study proposes Isa-VRd as a new SOC for patients with NDMM that are TI. ClinicalTrials.gov identifier: NCT04751877 .

2.
Hemoglobin ; 34(4): 389-93, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20642337

RESUMEN

A 37-year-old man presented a slight debility. The hemogram showed a phenotype of beta-thalassemia minor: Hb (13.1 g/dL), mean corpuscular volume (MCV) (62 fL) with low mean corpuscular hemoglobin (MCH) (20.8 pg), associated with a high level of Hb A(2) of 5.3%. The serum ferritin level was 1,072 ng/mL. The sequencing of the mutated fragment revealed a duplication of four bases of codons 7/8 involving a shift in the open reading frame starting from codon 9 with a TGA stop codon at codon 23: codons 7/8/9 (+AGAA); GAG.AAG.TCT(Gly-Lys-Ser)>GAG.AAAGAAG. The human hemoglobin (Hb) instability tests were negative. The patient did not present the high iron Fe (HFE) mutation (C282Y, H63D). The same mutation was found in five other unrelated families (representing a total of 23 patients). All of their ancestors came from the north of France. This mutation has not been described before and could have its origins in the native populations of Northern France.


Asunto(s)
Codón/genética , Mutación , Globinas beta/genética , Talasemia beta/genética , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Hermanos , Talasemia beta/patología
3.
Mol Genet Genomics ; 282(6): 633-52, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19856189

RESUMEN

Retrotransposons are mobile genetic elements, ubiquitous in Eukaryotic genomes, which have proven to be major genetic tools in determining phylogeny and structuring genetic diversity, notably in plants. We investigate here the diversity of the Ty1-copia retrotransposon Tos17 in the cultivated rice of Asian origin (Oryza sativa L.) and related AA genome species of the Oryza genus, to contribute understanding of the complex evolutionary history in this group of species through that of the element in the lineages. In that aim, we used a combination of Southern hybridization with a reverse transcriptase (RT) probe and an adapter-PCR mediated amplification, which allowed the sequencing of the genomic regions flanking Tos17 insertions. This analysis was carried out in a collection of 47 A-genome Oryza species accessions and 202 accessions of a core collection of Oryza sativa L. representative of the diversity of the species. Our Southern hybridization results show that Tos17 is present in all the accessions of the A-genome Oryza species, except for the South American species O. glumaepatula and the African species O. glaberrima and O. breviligulata. In O. sativa, the number of putative copies of Tos17 per accession ranged from 1 to 11 and multivariate analysis based on presence/absence of putative copies yielded a varietal clustering which is consistent with the isozyme classification of rice. Adapter PCR amplification and sequencing of flanking regions of Tos17 insertions in A-genome species other than O. sativa, followed by anchoring on the Nipponbare genome sequence, revealed 13 insertion sites of Tos17 in the surveyed O. rufipogon and O. longistaminata accessions, including one shared by both species. In O. sativa, the same approach revealed 25 insertions in the 6 varietal groups. Four insertion sites located on chromosomes 1, 2, 10, and 11 were found orthologous in O. rufipogon and O. sativa. The chromosome 1 insertion was also shared between O. rufipogon and O. longistaminata. The presence of Tos17 at three insertion sites was confirmed by retrotransposon-based insertion polymorphism (RBIP) in a sample of O. sativa accessions. The first insertion, located on chromosome 3 was only found in two japonica accessions from the Bhutan region while the second insertion, located on chromosome 10 was specific to the varietal groups 1, 2, and 5. The third insertion located on chromosome 7 corresponds to the only insertion shown active in rice so far, notably in cv. Nipponbare, where it has been extensively used for insertion mutagenesis. This copy was only found in a few varieties of the japonica group 6 and in one group 5 accession. Taken together, these results confirm that Tos17 was probably present in the ancestor of A-genome species and that some copies of the element remained active in some Oryza lineages--notably in O. rufipogon and O. longistaminata--as well as in the indica and japonica O. sativa L. lineages.


Asunto(s)
Variación Genética , Genoma de Planta , Oryza/genética , Retroelementos , Filogenia , Especificidad por Sustrato
4.
Blood ; 112(4): 999-1004, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18463354

RESUMEN

Whether rituximab could effectively and safely avoid splenectomy for adults with chronic immune thrombocytopenic purpura (ITP) remains unresolved. A multicenter, prospective, open-label, single-arm, phase 2 trial was conducted to assess rituximab safety and efficacy in adult splenectomy candidates with chronic ITP. Sixty patients with chronic (>or= 6 months) ITP and platelet counts less than 30 x 10(9)/L received a weekly intravenous infusion of rituximab (375 mg/m(2)) for 4 weeks. All other ITP treatments were stopped. A good response was defined as a platelet count 50 x 10(9)/L or more, with at least a doubling of the initial value at 1 and 2 years after the first rituximab infusion. Patients who required another treatment during follow up were considered nonresponders. Sixteen patients experienced transient side effects that necessitated treatment discontinuation for only 1. Good 1-year responses were obtained in 40% of the patients (24/60 [95% confidence interval: 28%-52%]). At 2 years, 33.3% (20/60 patients) had good responses and 6.7% (4/60) had sustained platelet counts of 30 x 10(9)/L or more without treatment. Thirty-six (60%) patients failed to respond; 25 underwent splenectomy. Based on these results, rituximab was an apparently safe and effective splenectomy-avoiding option in some adults with chronic ITP. This trial is registered at http://clinicaltrials.gov as NCT00225875.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Esplenectomía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/toxicidad , Anticuerpos Monoclonales de Origen Murino , Enfermedad Crónica , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Inducción de Remisión , Rituximab , Resultado del Tratamiento
5.
Lancet ; 371(9610): 395-403, 2008 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-18242413

RESUMEN

BACKGROUND: Chronic immune thrombocytopenic purpura (ITP) is characterised by accelerated platelet destruction and decreased platelet production. Short-term administration of the thrombopoiesis-stimulating protein, romiplostim, has been shown to increase platelet counts in most patients with chronic ITP. We assessed the long-term administration of romiplostim in splenectomised and non-splenectomised patients with ITP. METHODS: In two parallel trials, 63 splenectomised and 62 non-splenectomised patients with ITP and a mean of three platelet counts 30x10(9)/L or less were randomly assigned 2:1 to subcutaneous injections of romiplostim (n=42 in splenectomised study and n=41 in non-splenectomised study) or placebo (n=21 in both studies) every week for 24 weeks. Doses of study drug were adjusted to maintain platelet counts of 50x10(9)/L to 200x10(9)/L. The primary objectives were to assess the efficacy of romiplostim as measured by a durable platelet response (platelet count > or =50x10(9)/L during 6 or more of the last 8 weeks of treatment) and treatment safety. Analysis was per protocol. These studies are registered with ClinicalTrials.gov, numbers NCT00102323 and NCT00102336. FINDINGS: A durable platelet response was achieved by 16 of 42 splenectomised patients given romplostim versus none of 21 given placebo (difference in proportion of patients responding 38% [95% CI 23.4-52.8], p=0.0013), and by 25 of 41 non-splenectomised patients given romplostim versus one of 21 given placebo (56% [38.7-73.7], p<0.0001). The overall platelet response rate (either durable or transient platelet response) was noted in 88% (36/41) of non-splenectomised and 79% (33/42) of splenectomised patients given romiplostim compared with 14% (three of 21) of non-splenectomised and no splenectomised patients given placebo (p<0.0001). Patients given romiplostim achieved platelet counts of 50x10(9)/L or more on a mean of 13.8 (SE 0.9) weeks (mean 12.3 [1.2] weeks in splenectomised group vs 15.2 [1.2] weeks in non-splenectomised group) compared with 0.8 (0.4) weeks for those given placebo (0.2 [0.1] weeks vs 1.3 [0.8] weeks). 87% (20/23) of patients given romiplostim (12/12 splenectomised and eight of 11 non-splenectomised patients) reduced or discontinued concurrent therapy compared with 38% (six of 16) of those given placebo (one of six splenectomised and five of ten non-splenectomised patients). Adverse events were much the same in patients given romiplostim and placebo. No antibodies against romiplostim or thrombopoietin were detected. INTERPRETATION: Romiplostim was well tolerated, and increased and maintained platelet counts in splenectomised and non-splenectomised patients with ITP. Many patients were able to reduce or discontinue other ITP medications. Stimulation of platelet production by romiplostim may provide a new therapeutic option for patients with ITP.


Asunto(s)
Proteínas Portadoras/uso terapéutico , Púrpura Trombocitopénica Trombótica/tratamiento farmacológico , Receptores Fc/uso terapéutico , Adulto , Anciano , Proteínas Portadoras/administración & dosificación , Proteínas Portadoras/efectos adversos , Enfermedad Crónica/tratamiento farmacológico , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Púrpura Trombocitopénica Trombótica/sangre , Púrpura Trombocitopénica Trombótica/inmunología , Receptores Fc/administración & dosificación , Proteínas Recombinantes de Fusión , Esplenectomía , Trombopoyetina , Resultado del Tratamiento
6.
Plant Mol Biol ; 65(5): 587-601, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17874225

RESUMEN

We characterized the insertion sites of newly transposed copies of the tissue-culture-induced ty1-copia retrotransposon Tos17 in the Oryza Tag Line (OTL) T-DNA mutant library of rice cv. Nipponbare. While Nipponbare contains two native copies of Tos17 the number of additional copies, deduced from Southern blot analyses in a subset of 384 T-DNA lines and using a reverse transcriptase probe specific to the element, ranged from 1 to 8 and averaged 3.37. These copies were shown to be stably inherited and to segregate independently in the progenies of insertion lines. We took advantage of the absence of EcoRV restriction sites in the immediate vicinity of the 3' LTR of the native copies of Tos17 in the genome sequence of cv. Nipponbare, thereby preventing amplification of corresponding PCR fragments, to efficiently and selectively amplify and sequence flanking regions of newly transposed Tos17 inserts. From 25,286 T-DNA plants, we recovered 19,252 PCR products (76.1%), which were sequenced yielding 14,513 FSTs anchored on the rice pseudomolecules. Following elimination of redundant sequences due to the presence of T-DNA plants deriving from the same cell lineage, these FSTs corresponded to 11,689 unique insertion sites. These unique insertions exhibited higher densities in subtelomeric regions of the chromosomes and hot spots for integration, following a distribution that remarkably paralleled that of Tos17 sites in the National Institute for Agrobiological Sciences (NIAS) library. The insertion sites were mostly found in genic regions (77.5%) and preferably in coding sequences (68.8%) compared to unique T-DNA insertion sites in the same materials (49.1% and 28.3%, respectively). Predicted non- transposable element (TE) genes prone to a high frequency of Tos17 integration (i.e. from 5 to 121 inserts) in the OTL T-DNA collection were generally found to be also hot spots for integration in the NIAS library. The 9,060 Tos17 inserts inserted into non TE genes were found to disrupt a total of 2,773 genes with an average of 3.27 inserts per gene, similar to that in the NIAS library (3.28 inserts per gene on average) whereas the 4,472 T-DNA inserted into genes in the same materials disrupted a total of 3,911 genes (1.14 inserts per gene on average). Interestingly, genes disrupted by both Tos17 and T-DNA inserts in the library represented only 14.9% and 10.6% of the complement of genes interrupted by Tos17 and T-DNA inserts respectively while 52.1% of the genes tagged by Tos17 inserts in the OTL library were found to be tagged also in the NIAS Tos17 library. We concluded that the first advantage in characterizing Tos17 inserts in a rice T-DNA collection lies in a complementary tagging of novel genes and secondarily in finding other alleles in a same genetic background, thereby greatly enhancing the library genome coverage and its overall value for implementing forward and reverse genetics strategies.


Asunto(s)
ADN Bacteriano , Oryza/genética , Retroelementos , Southern Blotting , Cromosomas de las Plantas , ADN de Plantas/química , Mutagénesis Insercional , Mutación , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Lugares Marcados de Secuencia
7.
Eur J Haematol ; 77(2): 145-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16608501

RESUMEN

BACKGROUND: Liver iron content (LIC) assessment by magnetic resonance imaging (MRI) is validated but not standardized. In a single center, we tried to assess the accuracy of a specific, simple MRI procedure adapted to high LIC from a well-established simple and routine procedure known to quantify LIC. METHODS: In 27 cases of monthly transfused patients, we compared biochemical values of LIC assessed on liver biopsy specimens and results obtained by two signal intensity ratio of gradient echo imaging (R2*) MRI protocols. The first was Gandon's routine procedure previously validated in liver disease and the second, our own method, was an addition of a gradient echo sequence specifically adapted to high LIC encountered in hematology practice. RESULTS: Twenty-seven liver biopsies were performed in 18 adult patients (myelodysplastic syndrome = 5, beta-thalassemia = 13). LIC by biopsy ranged from 1.4 to 54 mg/g liver dry weight (mg/g dw) (median 9.4 mg/g dw). Correlation between LIC by biopsy and by MRI with Gandon's procedure was good (R = 0.80) in patients with LIC falling within the range reported by Gandon. By contrast, a weak correlation was demonstrated (R = 0.52) in patients with high LIC (above 11.2 mg/g dw). With our sequences, the correlation was good both in the entire group of patients (R = 0.83) and in patients with LIC above 11.2 mg/g dw (R = 0.85). CONCLUSION: Our results suggest that the addition of a specific shorter-gradient echo sequence to a very simple, fast technique produces an accurate estimation of LIC in post-transfusional iron overload.


Asunto(s)
Sobrecarga de Hierro/diagnóstico , Hierro/análisis , Hígado/química , Imagen por Resonancia Magnética/métodos , Reacción a la Transfusión , Adolescente , Adulto , Anciano , Biopsia , Femenino , Humanos , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/terapia , Talasemia beta/patología , Talasemia beta/terapia
8.
Plant J ; 39(3): 450-64, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15255873

RESUMEN

A library of 29,482 T-DNA enhancer trap lines has been generated in rice cv. Nipponbare. The regions flanking the T-DNA left border from the first 12,707 primary transformants were systematically isolated by adapter anchor PCR and sequenced. A survey of the 7480 genomic sequences larger than 30 bp (average length 250 bp), representing 56.4% of the total readable sequences and matching the rice bacterial artificial chromosome/phage artificial chromosome (BAC/PAC) sequences assembled in pseudomolecules allowed the assigning of 6645 (88.8%) T-DNA insertion sites to at least one position in the rice genome of cv. Nipponbare. T-DNA insertions appear to be rather randomly distributed over the 12 rice chromosomes, with a slightly higher insertion frequency in chromosomes 1, 2, 3 and 6. The distribution of 723 independent T-DNA insertions along the chromosome 1 pseudomolecule did not differ significantly from that of the predicted coding sequences in exhibiting a lower insertion density around the centromere region and a higher density in the subtelomeric regions where the gene density is higher. Further establishment of density graphs of T-DNA inserts along the recently released 12 rice pseudomolecules confirmed this non-uniform chromosome distribution. T-DNA appeared less prone to hot spots and cold spots of integration when compared with those revealed by a concurrent assignment of the Tos17 retrotransposon flanking sequences deposited in the National Center for Biotechnology Information (NCBI). T-DNA inserts rarely integrated into repetitive sequences. Based on the predicted gene annotation of chromosome 1, preferential insertion within the first 250 bp from the putative ATG start codon has been observed. Using 4 kb of sequences surrounding the insertion points, 62% of the sequences showed significant similarity to gene encoding known proteins (E-value < 1.00 e(-05)). To illustrate the in silico reverse genetic approach, identification of 83 T-DNA insertions within genes coding for transcription factors (TF) is presented. Based both on the estimated number of members of several large TF gene families (e.g. Myb, WRKY, HD-ZIP, Zinc-finger) and on the frequency of insertions in chromosome 1 predicted genes, we could extrapolate that 7-10% of the rice gene complement is already tagged by T-DNA insertion in the 6116 independent transformant population. This large resource is of high significance while assisting studies unravelling gene function in rice and cereals, notably through in silico reverse genetics.


Asunto(s)
ADN Bacteriano/genética , Mutagénesis Insercional/métodos , Oryza/genética , Secuencia de Bases , Cromosomas de las Plantas/genética , ADN de Plantas/genética , Elementos de Facilitación Genéticos , Vectores Genéticos , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Secuencias Repetitivas de Ácidos Nucleicos , Rhizobium/genética
9.
Br J Haematol ; 120(6): 1079-88, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12648082

RESUMEN

Splenectomy remains the most effective treatment of chronic autoimmune idiopathic thrombocytopenia (ITP) (i.e. of > 6 months duration). Treatment of patients refractory to splenectomy (with absence of response or relapse after initial response) is difficult, and their long-term outcome is not well known. Over a 10-year period, 183 patients with chronic ITP were splenectomized including 158 adults and 25 children ( 100 x 10(9)/l, nine of them without treatment and 27 of them with low-dose steroids or azathioprine; six (13%) remained moderately thrombocytopenic (35 x 10(9)/l to 100 x 10(9)/l platelets); the last five patients, without response to any treatment (up to six regimens), remained severely thrombocytopenic (platelets < 20 x 10(9)/l), and three of them died from bleeding. Twenty-seven (57%) of the 47 refractory cases required at least one hospitalization, in the majority of cases for intravenous immunoglobulin (IVIg) infusions. Seven of the refractory cases occurred in children. Six of them subsequently reached platelet counts > 100 x 10(9)/l, but one died from bleeding. Our findings confirm the overall favourable long-term prognosis of chronic ITP refractory to splenectomy.


Asunto(s)
Púrpura Trombocitopénica Idiopática/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/sangre , Recurrencia , Esplenectomía , Insuficiencia del Tratamiento
10.
New Phytol ; 140(3): 451-460, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33862875

RESUMEN

Swards of cocksfoot (cvs KM2, Lutetia) and perennial ryegrass (cvs Aurora, Vigor) were grown under full irrigation or severe (80 d) drought in a field experiment in the South of France. Responses of the bases of immature leaves plus enclosed tissues were made during the drought period and after rewatering. By the end of the drought, water content had fallen from 3·0 to 0·8 gwater g-1 dm , and osmotic potential from -1·0 to -4·5 MPa in all cvs. Measured minerals and water-soluble carbohydrates contributed, respectively, c 19 and 44% to osmotic potential in droughted leaf bases. The drought-sensitive cocksfoot cv. Lutetia was characterized by a large proportion of fructans having a low degree of polymerization (DP=3, 4). As drought progressed, accumulation of dehydrin transcripts and ABA were higher in leaf bases of the sensitive cv. Lutetia than in the resistant cv. KM2. After rewatering, the water status of immature leaf bases returned to control levels in 1-2 d, and then increased further as leaves began to grow and new tissue was produced. High-DP-fructans remained unchanged in leaf bases of 'Lutetia' but were depleted by over 55%, and therefore remobilized, in leaf bases of other cvs after 8 d. It is concluded that enclosed immature leaf bases survive drought by tolerating a low water status and that changes conventionally associated with desiccation tolerance are expressed most strongly in susceptible plants least able to maintain their water supply.

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