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1.
Plant Cell ; 24(9): 3838-52, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23023168

RESUMEN

Cytokinin regulates many aspects of plant development, and in legume crops, this phytohormone is necessary and sufficient for symbiotic nodule organogenesis, allowing them to fix atmospheric nitrogen. To identify direct links between cytokinins and nodule organogenesis, we determined a consensus sequence bound in vitro by a transcription factor (TF) acting in cytokinin signaling, the nodule-enhanced Medicago truncatula Mt RR1 response regulator (RR). Among genes rapidly regulated by cytokinins and containing this so-called RR binding site (RRBS) in their promoters, we found the nodulation-related Type-A RR Mt RR4 and the Nodulation Signaling Pathway 2 (NSP2) TF. Site-directed mutagenesis revealed that RRBS cis-elements in the RR4 and NSP2 promoters are essential for expression during nodule development and for cytokinin induction. Furthermore, a microRNA targeting NSP2 (miR171 h) is also rapidly induced by cytokinins and then shows an expression pattern anticorrelated with NSP2. Other primary targets regulated by cytokinins depending on the Cytokinin Response1 (CRE1) receptor were a cytokinin oxidase/dehydrogenase (CKX1) and a basic Helix-Loop-Helix TF (bHLH476). RNA interference constructs as well as insertion of a Tnt1 retrotransposon in the bHLH gene led to reduced nodulation. Hence, we identified two TFs, NSP2 and bHLH476, as direct cytokinin targets acting at the convergence of phytohormonal and symbiotic cues.


Asunto(s)
Citocininas/farmacología , Medicago truncatula/fisiología , Reguladores del Crecimiento de las Plantas/farmacología , Nodulación de la Raíz de la Planta/genética , Sinorhizobium meliloti/fisiología , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Secuencia de Consenso , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Medicago truncatula/efectos de los fármacos , Medicago truncatula/genética , Medicago truncatula/microbiología , MicroARNs/genética , Datos de Secuencia Molecular , Mutagénesis Insercional , Mutagénesis Sitio-Dirigida , Fijación del Nitrógeno , Análisis de Secuencia por Matrices de Oligonucleótidos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas/genética , Nódulos de las Raíces de las Plantas/efectos de los fármacos , Nódulos de las Raíces de las Plantas/genética , Nódulos de las Raíces de las Plantas/microbiología , Nódulos de las Raíces de las Plantas/fisiología , Plantones/efectos de los fármacos , Plantones/genética , Plantones/microbiología , Plantones/fisiología , Alineación de Secuencia , Transducción de Señal , Simbiosis , Factores de Transcripción/genética , Transcriptoma
2.
Front Microbiol ; 13: 1098133, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36909845

RESUMEN

Introduction: We compared the performance of real-time PCR with culture-based methods for identifying bacteria in sputum samples from patients with chronic obstructive pulmonary disease (COPD) in three studies. Methods: This was an exploratory analysis of sputum samples collected during an observational study of 127 patients (AERIS; NCT01360398), phase 2 study of 145 patients (NTHI-004; NCT02075541), and phase 2b study of 606 patients (NTHI-MCAT-002; NCT03281876). Bacteria were identified by culture-based microbiological methods in local laboratories using fresh samples or by real-time PCR in a central laboratory using frozen samples. Haemophilus influenzae positivity with culture was differentiated from H. haemolyticus positivity by microarray analysis or PCR. The feasibility of bacterial detection by culture-based methods on previously frozen samples was also examined in the NTHI-004 study. Results: Bacterial detection results from both culture-based and PCR assays were available from 2,293 samples from AERIS, 974 from the NTHI-004 study, and 1736 from the NTHI-MCAT-002 study. Quantitative real-time PCR (qPCR) showed higher positivity rates than culture for H. influenzae (percentages for each study: 43.4% versus 26.2%, 47.1% versus 23.6%, 32.7% versus 10.4%) and Moraxella catarrhalis (12.9% versus 6.3%, 19.0% versus 6.0%, 15.5% versus 4.1%). In the NTHI-004 and NTHI-MCAT-002 studies, positivity rates were higher with qPCR for Streptococcus pneumoniae (15.6% versus 6.1%, 15.5% versus 3.8%); in AERIS, a lower rate with qPCR than with culture (11.0% versus 17.4%) was explained by misidentification of S. pseudopneumoniae/mitis isolates via conventional microbiological methods. Concordance analysis showed lowest overall agreement for H. influenzae (82.0%, 75.6%, 77.6%), due mainly to culture-negative/qPCR-positive samples, indicating lower sensitivity of the culture-based methods. The lowest positive agreement (culture-positive/qPCR-positive samples) was observed for S. pneumoniae (35.1%, 71.2%, 71.2%). Bacterial load values for each species showed a proportion of culture-negative samples with a load detected by qPCR; for some samples, the loads were in line with those observed in culture-positive samples. In the NTHI-004 study, of fresh samples that tested culture-positive, less than 50% remained culture-positive when tested from freeze/thawed samples. In the NTHI-004 study, of fresh samples that tested culture-positive, less than 50% remained culture-positive when tested from freeze/thawed samples. Discussion: Real-time PCR on frozen sputum samples has enhanced sensitivity and specificity over culture-based methods, supporting its use for the identification of common respiratory bacterial species in patients with COPD.

3.
Oncologist ; 16(9): 1250-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21765195

RESUMEN

BACKGROUND: Prophylactic bilateral salpingo-oophorectomy (PBSO) might alter several components of well-being, such as sexual functioning and endocrine symptoms, in women at high risk for hereditary breast and/or ovarian cancer, compared with the general population. We searched for factors associated with altered long-term well-being in this population (lower quality of life [QOL], altered sexual functioning, greater anxiety, more endocrine symptoms). METHODS: All high-risk women who had undergone PBSO during the past 15 years in a single cancer center were contacted by mail. Upon acceptance, they were sent five questionnaires: (a) general social questions, (b) the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30, (c) Sexual Activity Questionnaire, (d) Functional Assessment of Cancer Therapy - Endocrine Symptom, and (5) State-Trait Anxiety Inventory. Logistic analyses were used to identify factors associated with altered results. Because of multiple testing, only p-values ≤ .01 were considered significant. RESULTS: One hundred twelve of 175 women (64%) returned the completed questionnaires at a mean duration (standard deviation) of 6.0 (5.1) years after PBSO. QOL was positively influenced by two baseline factors: a high educational level and occupying an executive position. However, younger age at PBSO was associated with lower social functioning and greater anxiety. At the time of the study, practicing a sport and the avoidance of weight gain (≥10%) were highly related to QOL, sexual pleasure, endocrine symptoms, and anxiety in the univariate analysis and predictive of better QOL and lower anxiety in the multivariate analysis. CONCLUSIONS: Younger women and women with a low educational level and no occupation appear to be at higher risk for altered long-term well-being. After surgery, practicing a sport and stable weight may help maintain overall well-being.


Asunto(s)
Neoplasias de la Mama/prevención & control , Trompas Uterinas/cirugía , Neoplasias Ováricas/prevención & control , Ovariectomía/métodos , Adulto , Anciano , Neoplasias de la Mama/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Análisis Multivariante , Neoplasias Ováricas/genética , Calidad de Vida , Medición de Riesgo , Factores de Riesgo
4.
Bioinformatics ; 23(17): 2339-41, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17586547

RESUMEN

UNLABELLED: MAnGO (Microarray Analysis at the Gif/Orsay platform) is an interactive R-based tool for the analysis of two-colour microarray experiments. It is a compilation of various methods, which allows the user (1) to control data quality by detecting biases with a large number of visual representations, (2) to pre-process data (filtering and normalization) and (3) to carry out differential analyses. MAnGO is not only a 'turn-key' tool, oriented towards biologists but also a flexible and adaptable R script oriented towards bioinformaticians. AVAILABILITY: http://bioinfome.cgm.cnrs-gif.fr/.


Asunto(s)
Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Programas Informáticos , Interfaz Usuario-Computador , Algoritmos , Hibridación Fluorescente in Situ/métodos , Lenguajes de Programación
5.
Physiol Genomics ; 29(2): 128-38, 2007 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-17179208

RESUMEN

We determined a transcriptional profile specific for clonal stromal mesenchymal stem cells from adult and fetal hematopoietic sites. To identify mesenchymal stem cell-like stromal cell lines, we evaluated the adipocytic, osteoblastic, chondrocytic, and vascular smooth muscle differentiation potential and also the hematopoietic supportive (stromal) capacity of six mouse stromal cell lines from adult bone marrow and day 14.5 fetal liver. We found that two lines were quadripotent and also supported hematopoiesis, BMC9 from bone marrow and AFT024 from fetal liver. We then ascertained the set of genes differentially expressed in the intersection set of AFT024 and BMC9 compared with those expressed in the union set of two negative control lines, 2018 and BFC012 (both from fetal liver); 346 genes were upregulated and 299 downregulated. Using Ingenuity software, we found two major gene networks with highly significant scores. One network contained downregulated genes that are known to be implicated in osteoblastic differentiation, proliferation, or transformation. The other network contained upregulated genes that belonged to two categories, cytoskeletal genes and genes implicated in the transcriptional machinery. The data extend the concept of stromal mesenchymal stem cells to clonal cell populations derived not only from bone marrow but also from fetal liver. The gene networks described should discriminate this cell type from other types of stem cells and help define the stem cell state.


Asunto(s)
Células de la Médula Ósea/metabolismo , Diferenciación Celular , Perfilación de la Expresión Génica , Redes Reguladoras de Genes/genética , Células Madre Mesenquimatosas/metabolismo , Células del Estroma/metabolismo , Animales , Western Blotting , Células de la Médula Ósea/fisiología , Línea Celular , Cartilla de ADN , Técnica del Anticuerpo Fluorescente , Hígado/citología , Células Madre Mesenquimatosas/fisiología , Ratones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células del Estroma/fisiología
6.
Mol Plant ; 5(5): 1068-81, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22419822

RESUMEN

Evolutionary diversity can be driven by the interaction of plants with different environments. Molecular bases involved in ecological adaptations to abiotic constraints can be explored using genomic tools. Legumes are major crops worldwide and soil salinity is a main stress affecting yield in these plants. We analyzed in the Medicago truncatula legume the root transcriptome of two genotypes having contrasting responses to salt stress: TN1.11, sampled in a salty Tunisian soil, and the reference Jemalong A17 genotype. TN1.11 plants show increased root growth under salt stress as well as a differential accumulation of sodium ions when compared to A17. Transcriptomic analysis revealed specific gene clusters preferentially regulated by salt in root apices of TN1.11, notably those related to the auxin pathway and to changes in histone variant isoforms. Many genes encoding transcription factors (TFs) were also differentially regulated between the two genotypes in response to salt. Among those selected for functional studies, overexpression in roots of the A17 genotype of the bHLH-type TF most differentially regulated between genotypes improved significantly root growth under salt stress. Despite the global complexity of the differential transcriptional responses, we propose that an increase in this bHLH TF expression may be linked to the adaptation of M. truncatula to saline soil environments.


Asunto(s)
Perfilación de la Expresión Génica , Medicago truncatula/genética , Raíces de Plantas/metabolismo , Cloruro de Sodio/metabolismo , Adaptación Fisiológica , Regulación de la Expresión Génica de las Plantas , Genotipo , Medicago truncatula/crecimiento & desarrollo , Medicago truncatula/metabolismo , Datos de Secuencia Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo
7.
Eur J Cancer ; 48(15): 2409-16, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22633624

RESUMEN

AIM: This phase II study evaluated efficacy, safety and pharmacokinetics (PK) profile of combination intravenous vinorelbine (VNL) and continuous low doses oral cyclophosphamide (CPM) combination in children and young adults with a recurrent or refractory solid tumour. METHODS: A total of 117 patients (median age, 12 years) within six disease strata received intravenous VNL 25mg/m(2) on days 1, 8 and 15 of each 28-day cycle combined with continuous daily oral CPM 25mg/m(2). Tumour response was assessed every two cycles according to WHO (World Health Organisation) criteria. PK of VNL was investigated in a subset of 18 patients aged 4-15 years. RESULTS: In rhabdomyosarcoma (RMS) (n=50), the best overall response rate (ORR) was 36% with four complete (8%) and 14 partial responses (28%). The best ORR was 13% in Ewing's sarcoma (n=15), 6% in non-RMS soft tissue sarcoma (n=16) and 6% in neuroblastoma (n=16). No response was observed in osteosarcoma (n=10) and medulloblastoma (n=7). The main grade 3/4 toxicity was neutropenia (38%). Other severe toxicities were limited with 3% of peripheral neuropathy and no haemorrhagic cystitis. The PK analysis revealed equivalent blood exposure to VNL between children >4 years and adult series when the VNL dose was based on the body surface area-based dosing. CONCLUDING STATEMENT: In heavily pre-treated children, VNL combined with CPM showed an interesting response rate in RMS and an acceptable toxicity profile supporting further evaluation of these agents in phase III trials.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Rabdomiosarcoma/tratamiento farmacológico , Sarcoma/tratamiento farmacológico , Adolescente , Adulto , Neoplasias Óseas/metabolismo , Niño , Preescolar , Ciclofosfamida/administración & dosificación , Ciclofosfamida/farmacocinética , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Lactante , Masculino , Recurrencia , Rabdomiosarcoma/metabolismo , Sarcoma/metabolismo , Vinblastina/administración & dosificación , Vinblastina/análogos & derivados , Vinblastina/farmacocinética , Vinorelbina , Adulto Joven
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