41 research outputs found
Whole Genome Expression Array Profiling Highlights Differences in Mucosal Defense Genes in Barrett's Esophagus and Esophageal Adenocarcinoma
Esophageal adenocarcinoma (EAC) has become a major concern in Western countries due to rapid rises in incidence coupled with very poor survival rates. One of the key risk factors for the development of this cancer is the presence of Barrett's esophagus (BE), which is believed to form in response to repeated gastro-esophageal reflux. In this study we performed comparative, genome-wide expression profiling (using Illumina whole-genome Beadarrays) on total RNA extracted from esophageal biopsy tissues from individuals with EAC, BE (in the absence of EAC) and those with normal squamous epithelium. We combined these data with publically accessible raw data from three similar studies to investigate key gene and ontology differences between these three tissue states. The results support the deduction that BE is a tissue with enhanced glycoprotein synthesis machinery (DPP4, ATP2A3, AGR2) designed to provide strong mucosal defenses aimed at resisting gastro-esophageal reflux. EAC exhibits the enhanced extracellular matrix remodeling (collagens, IGFBP7, PLAU) effects expected in an aggressive form of cancer, as well as evidence of reduced expression of genes associated with mucosal (MUC6, CA2, TFF1) and xenobiotic (AKR1C2, AKR1B10) defenses. When our results are compared to previous whole-genome expression profiling studies keratin, mucin, annexin and trefoil factor gene groups are the most frequently represented differentially expressed gene families. Eleven genes identified here are also represented in at least 3 other profiling studies. We used these genes to discriminate between squamous epithelium, BE and EAC within the two largest cohorts using a support vector machine leave one out cross validation (LOOCV) analysis. While this method was satisfactory for discriminating squamous epithelium and BE, it demonstrates the need for more detailed investigations into profiling changes between BE and EAC
Language development after cochlear implantation: an epigenetic model
Growing evidence supports the notion that dynamic gene expression, subject to epigenetic control, organizes multiple influences to enable a child to learn to listen and to talk. Here, we review neurobiological and genetic influences on spoken language development in the context of results of a longitudinal trial of cochlear implantation of young children with severe to profound sensorineural hearing loss in the Childhood Development after Cochlear Implantation study. We specifically examine the results of cochlear implantation in participants who were congenitally deaf (N = 116). Prior to intervention, these participants were subject to naturally imposed constraints in sensory (acoustic–phonologic) inputs during critical phases of development when spoken language skills are typically achieved rapidly. Their candidacy for a cochlear implant was prompted by delays (n = 20) or an essential absence of spoken language acquisition (n = 96). Observations thus present an opportunity to evaluate the impact of factors that influence the emergence of spoken language, particularly in the context of hearing restoration in sensitive periods for language acquisition. Outcomes demonstrate considerable variation in spoken language learning, although significant advantages exist for the congenitally deaf children implanted prior to 18 months of age. While age at implantation carries high predictive value in forecasting performance on measures of spoken language, several factors show significant association, particularly those related to parent–child interactions. Importantly, the significance of environmental variables in their predictive value for language development varies with age at implantation. These observations are considered in the context of an epigenetic model in which dynamic genomic expression can modulate aspects of auditory learning, offering insights into factors that can influence a child’s acquisition of spoken language after cochlear implantation. Increased understanding of these interactions could lead to targeted interventions that interact with the epigenome to influence language outcomes with intervention, particularly in periods in which development is subject to time-sensitive experience
Indices for the determination of the degree of communication skills improvement in prelingual children with cochlear implantation
En Abstract Introduction Monitoring and documenting the progress in communication skills of cochlear implanted (CI) children is important for intervention planning, conduction of evidence-based studies, and reporting parents about their children’s progress. Aim The aim of the present study was to provide reliable indices that may be used to monitor a child’s communication skills progress after CI and to grade his or her performance. Patients The study was carried out on 53 prelingual CI children (28 boys and 25 girls). Their ages ranged from 2.5 to 6 years. They were all of average intelligence and showed no associated disorders. They were all enrolled for verbal auditory training at the Unit of Phoniatrics. Methodology The CI children were evaluated postoperatively using the quasi-objective description of communicative ability, following scaling by transformation from the lower stages to the higher stages in communicative performance. This entailed the determination of the levels for auditory performance, receptive and expressive language, speech intelligibility, mode of communication, approximate language age, vocabulary size, and speech sounds perception. After 1 year of implantation, the children were re-evaluated and the levels achieved in each item and on the therapy program were recorded. The subjective impression of improvement was marked as poor, fair, or good, which was determined by the phoniatrician, therapist, and the parents for each child. Conclusion Expressive language development and speech intelligibility in the presence of marked speech perception are significant indicators for communication skills progress. The indices provided for various degrees of improvement are helpful to conduct evidence-based research, especially in the absence of reliable formal testing