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1.
J Acoust Soc Am ; 151(5): 3369, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35649936

RESUMEN

Lexical bias is the tendency to perceive an ambiguous speech sound as a phoneme completing a word; more ambiguity typically causes greater reliance on lexical knowledge. A speech sound ambiguous between /g/ and /k/ is more likely to be perceived as /g/ before /ɪft/ and as /k/ before /ɪs/. The magnitude of this difference-the Ganong shift-increases when high cognitive load limits available processing resources. The effects of stimulus naturalness and informational masking on Ganong shifts and reaction times were explored. Tokens between /gɪ/ and /kɪ/ were generated using morphing software, from which two continua were created ("giss"-"kiss" and "gift"-"kift"). In experiment 1, Ganong shifts were considerably larger for sine- than noise-vocoded versions of these continua, presumably because the spectral sparsity and unnatural timbre of the former increased cognitive load. In experiment 2, noise-vocoded stimuli were presented alone or accompanied by contralateral interferers with constant within-band amplitude envelope, or within-band envelope variation that was the same or different across bands. The latter, with its implied spectro-temporal variation, was predicted to cause the greatest cognitive load. Reaction-time measures matched this prediction; Ganong shifts showed some evidence of greater lexical bias for frequency-varying interferers, but were influenced by context effects and diminished over time.


Asunto(s)
Percepción del Habla , Sesgo , Ruido/efectos adversos , Fonética , Tiempo de Reacción
2.
Nature ; 521(7553): 489-94, 2015 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-26017449

RESUMEN

Patients with high-grade serous ovarian cancer (HGSC) have experienced little improvement in overall survival, and standard treatment has not advanced beyond platinum-based combination chemotherapy, during the past 30 years. To understand the drivers of clinical phenotypes better, here we use whole-genome sequencing of tumour and germline DNA samples from 92 patients with primary refractory, resistant, sensitive and matched acquired resistant disease. We show that gene breakage commonly inactivates the tumour suppressors RB1, NF1, RAD51B and PTEN in HGSC, and contributes to acquired chemotherapy resistance. CCNE1 amplification was common in primary resistant and refractory disease. We observed several molecular events associated with acquired resistance, including multiple independent reversions of germline BRCA1 or BRCA2 mutations in individual patients, loss of BRCA1 promoter methylation, an alteration in molecular subtype, and recurrent promoter fusion associated with overexpression of the drug efflux pump MDR1.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Genoma Humano/genética , Neoplasias Ováricas/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Estudios de Cohortes , Ciclina E/genética , Cistadenocarcinoma Seroso/tratamiento farmacológico , Cistadenocarcinoma Seroso/genética , Metilación de ADN , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Femenino , Genes BRCA1 , Genes BRCA2 , Genes de Neurofibromatosis 1 , Mutación de Línea Germinal/genética , Humanos , Mutagénesis/genética , Proteínas Oncogénicas/genética , Neoplasias Ováricas/tratamiento farmacológico , Fosfohidrolasa PTEN/genética , Regiones Promotoras Genéticas/genética , Proteína de Retinoblastoma/genética
3.
J Acoust Soc Am ; 150(5): 3693, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34852626

RESUMEN

Speech-on-speech informational masking arises because the interferer disrupts target processing (e.g., capacity limitations) or corrupts it (e.g., intrusions into the target percept); the latter should produce predictable errors. Listeners identified the consonant in monaural buzz-excited three-formant analogues of approximant-vowel syllables, forming a place of articulation series (/w/-/l/-/j/). There were two 11-member series; the vowel was either high-front or low-back. Series members shared formant-amplitude contours, fundamental frequency, and F1+F3 frequency contours; they were distinguished solely by the F2 frequency contour before the steady portion. Targets were always presented in the left ear. For each series, F2 frequency and amplitude contours were also used to generate interferers with altered source properties-sine-wave analogues of F2 (sine bleats) matched to their buzz-excited counterparts. Accompanying each series member with a fixed mismatched sine bleat in the contralateral ear produced systematic and predictable effects on category judgments; these effects were usually largest for bleats involving the fastest rate or greatest extent of frequency change. Judgments of isolated sine bleats using the three place labels were often unsystematic or arbitrary. These results indicate that informational masking by interferers involved corruption of target processing as a result of mandatory dichotic integration of F2 information, despite the grouping cues disfavoring this integration.


Asunto(s)
Inteligibilidad del Habla , Percepción del Habla , Estimulación Acústica , Juicio , Fonética , Acústica del Lenguaje
4.
Ann Surg ; 272(2): 366-376, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32675551

RESUMEN

OBJECTIVE: We aimed to define preoperative clinical and molecular characteristics that would allow better patient selection for operative resection. BACKGROUND: Although we use molecular selection methods for systemic targeted therapies, these principles are not applied to surgical oncology. Improving patient selection is of vital importance for the operative treatment of pancreatic cancer (pancreatic ductal adenocarcinoma). Although surgery is the only chance of long-term survival, 80% still succumb to the disease and approximately 30% die within 1 year, often sooner than those that have unresected local disease. METHOD: In 3 independent pancreatic ductal adenocarcinoma cohorts (total participants = 1184) the relationship between aberrant expression of prometastatic proteins S100A2 and S100A4 and survival was assessed. A preoperative nomogram based on clinical variables available before surgery and expression of these proteins was constructed and compared to traditional measures, and a postoperative nomogram. RESULTS: High expression of either S100A2 or S100A4 was independent poor prognostic factors in a training cohort of 518 participants. These results were validated in 2 independent patient cohorts (Glasgow, n = 198; Germany, n = 468). Aberrant biomarker expression stratified the cohorts into 3 distinct prognostic groups. A preoperative nomogram incorporating S100A2 and S100A4 expression predicted survival and nomograms derived using postoperative clinicopathological variables. CONCLUSIONS: Of those patients with a poor preoperative nomogram score, approximately 50% of patients died within a year of resection. Nomograms have the potential to improve selection for surgery and neoadjuvant therapy, avoiding surgery in aggressive disease, and justifying more extensive resections in biologically favorable disease.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidad , Factores Quimiotácticos/genética , Pancreatectomía/métodos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidad , Proteínas S100/genética , Anciano , Carcinoma Ductal Pancreático/cirugía , Causas de Muerte , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Nomogramas , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/cirugía , Selección de Paciente , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia
5.
Hum Mol Genet ; 25(15): 3269-3283, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27378691

RESUMEN

Predicting response to endocrine therapy and survival in oestrogen receptor positive breast cancer is a significant clinical challenge and novel prognostic biomarkers are needed. Long-range regulators of gene expression are emerging as promising biomarkers and therapeutic targets for human diseases, so we have explored the potential of distal enhancer elements of non-coding RNAs in the prognostication of breast cancer survival. HOTAIR is a long non-coding RNA that is overexpressed, promotes metastasis and is predictive of decreased survival. Here, we describe a long-range transcriptional enhancer of the HOTAIR gene that binds several hormone receptors and associated transcription factors, interacts with the HOTAIR promoter and augments transcription. This enhancer is dependent on Forkhead-Box transcription factors and functionally interacts with a novel alternate HOTAIR promoter. HOTAIR expression is negatively regulated by oestrogen, positively regulated by FOXA1 and FOXM1, and is inversely correlated with oestrogen receptor and directly correlated with FOXM1 in breast tumours. The combination of HOTAIR and FOXM1 enables greater discrimination of endocrine therapy responders and non-responders in patients with oestrogen receptor positive breast cancer. Consistent with this, HOTAIR expression is increased in cell-line models of endocrine resistance. Analysis of breast cancer gene expression data indicates that HOTAIR is co-expressed with FOXA1 and FOXM1 in HER2-enriched tumours, and these factors enhance the prognostic power of HOTAIR in aggressive HER2+ breast tumours. Our study elucidates the transcriptional regulation of HOTAIR, identifies HOTAIR and its regulators as novel biomarkers of patient response to endocrine therapy and corroborates the importance of transcriptional enhancers in cancer.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/biosíntesis , ARN Neoplásico/biosíntesis , Transcripción Genética , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Proteína Forkhead Box M1/biosíntesis , Proteína Forkhead Box M1/genética , Factor Nuclear 3-alfa del Hepatocito/biosíntesis , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Células MCF-7 , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , ARN Largo no Codificante/genética , ARN Neoplásico/genética
6.
Gastroenterology ; 152(1): 68-74.e2, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27856273

RESUMEN

Pancreatic cancer is molecularly diverse, with few effective therapies. Increased mutation burden and defective DNA repair are associated with response to immune checkpoint inhibitors in several other cancer types. We interrogated 385 pancreatic cancer genomes to define hypermutation and its causes. Mutational signatures inferring defects in DNA repair were enriched in those with the highest mutation burdens. Mismatch repair deficiency was identified in 1% of tumors harboring different mechanisms of somatic inactivation of MLH1 and MSH2. Defining mutation load in individual pancreatic cancers and the optimal assay for patient selection may inform clinical trial design for immunotherapy in pancreatic cancer.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Reparación de la Incompatibilidad de ADN/genética , Mutación , Neoplasias Pancreáticas/genética , Transcriptoma , Adulto , Anciano , Anciano de 80 o más Años , Análisis Mutacional de ADN , Femenino , Genoma , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , Proteínas Proto-Oncogénicas p21(ras)/genética
7.
Am J Hum Genet ; 92(4): 489-503, 2013 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-23540573

RESUMEN

Analysis of 4,405 variants in 89,050 European subjects from 41 case-control studies identified three independent association signals for estrogen-receptor-positive tumors at 11q13. The strongest signal maps to a transcriptional enhancer element in which the G allele of the best candidate causative variant rs554219 increases risk of breast cancer, reduces both binding of ELK4 transcription factor and luciferase activity in reporter assays, and may be associated with low cyclin D1 protein levels in tumors. Another candidate variant, rs78540526, lies in the same enhancer element. Risk association signal 2, rs75915166, creates a GATA3 binding site within a silencer element. Chromatin conformation studies demonstrate that these enhancer and silencer elements interact with each other and with their likely target gene, CCND1.


Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 11/genética , Ciclina D1/genética , Elementos de Facilitación Genéticos/genética , Polimorfismo de Nucleótido Simple/genética , Sitios de Unión , Estudios de Casos y Controles , Línea Celular Tumoral , Cromatina/química , Cromatina/genética , Inmunoprecipitación de Cromatina , Ciclina D1/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Femenino , Factor de Transcripción GATA3/antagonistas & inhibidores , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Luciferasas/metabolismo , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Elementos Silenciadores Transcripcionales/genética , Proteína Elk-4 del Dominio ets/antagonistas & inhibidores , Proteína Elk-4 del Dominio ets/genética , Proteína Elk-4 del Dominio ets/metabolismo
8.
J Pathol ; 237(3): 363-78, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26172396

RESUMEN

Treatment options for patients with brain metastases (BMs) have limited efficacy and the mortality rate is virtually 100%. Targeted therapy is critically under-utilized, and our understanding of mechanisms underpinning metastatic outgrowth in the brain is limited. To address these deficiencies, we investigated the genomic and transcriptomic landscapes of 36 BMs from breast, lung, melanoma and oesophageal cancers, using DNA copy-number analysis and exome- and RNA-sequencing. The key findings were as follows. (a) Identification of novel candidates with possible roles in BM development, including the significantly mutated genes DSC2, ST7, PIK3R1 and SMC5, and the DNA repair, ERBB-HER signalling, axon guidance and protein kinase-A signalling pathways. (b) Mutational signature analysis was applied to successfully identify the primary cancer type for two BMs with unknown origins. (c) Actionable genomic alterations were identified in 31/36 BMs (86%); in one case we retrospectively identified ERBB2 amplification representing apparent HER2 status conversion, then confirmed progressive enrichment for HER2-positivity across four consecutive metastatic deposits by IHC and SISH, resulting in the deployment of HER2-targeted therapy for the patient. (d) In the ERBB/HER pathway, ERBB2 expression correlated with ERBB3 (r(2) = 0.496; p < 0.0001) and HER3 and HER4 were frequently activated in an independent cohort of 167 archival BM from seven primary cancer types: 57.6% and 52.6% of cases were phospho-HER3(Y1222) or phospho-HER4(Y1162) membrane-positive, respectively. The HER3 ligands NRG1/2 were barely detectable by RNAseq, with NRG1 (8p12) genomic loss in 63.6% breast cancer-BMs, suggesting a microenvironmental source of ligand. In summary, this is the first study to characterize the genomic landscapes of BM. The data revealed novel candidates, potential clinical applications for genomic profiling of resectable BMs, and highlighted the possibility of therapeutically targeting HER3, which is broadly over-expressed and activated in BMs, independent of primary site and systemic therapy.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Perfilación de la Expresión Génica/métodos , Genómica/métodos , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/enzimología , Análisis Mutacional de ADN , Activación Enzimática , Amplificación de Genes , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Ligandos , Terapia Molecular Dirigida , Mutación , Fenotipo , Fosforilación , Medicina de Precisión , Valor Predictivo de las Pruebas , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo , Microambiente Tumoral
10.
J Acoust Soc Am ; 140(2): 1227, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27586751

RESUMEN

The role of source properties in across-formant integration was explored using three-formant (F1+F2+F3) analogues of natural sentences (targets). In experiment 1, F1+F3 were harmonic analogues (H1+H3) generated using a monotonous buzz source and second-order resonators; in experiment 2, F1+F3 were tonal analogues (T1+T3). F2 could take either form (H2 or T2). Target formants were always presented monaurally; the receiving ear was assigned randomly on each trial. In some conditions, only the target was present; in others, a competitor for F2 (F2C) was presented contralaterally. Buzz-excited or tonal competitors were created using the time-reversed frequency and amplitude contours of F2. Listeners must reject F2C to optimize keyword recognition. Whether or not a competitor was present, there was no effect of source mismatch between F1+F3 and F2. The impact of adding F2C was modest when it was tonal but large when it was harmonic, irrespective of whether F2C matched F1+F3. This pattern was maintained when harmonic and tonal counterparts were loudness-matched (experiment 3). Source type and competition, rather than acoustic similarity, governed the phonetic contribution of a formant. Contrary to earlier research using dichotic targets, requiring across-ear integration to optimize intelligibility, H2C was an equally effective informational masker for H2 as for T2.


Asunto(s)
Acústica del Lenguaje , Inteligibilidad del Habla/fisiología , Estimulación Acústica , Humanos , Fonética , Distribución Aleatoria , Percepción del Habla
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