Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.570
Filtrar
1.
J Neurosci ; 44(28)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38830759

RESUMEN

Congenital single-sided deafness (SSD) leads to an aural preference syndrome that is characterized by overrepresentation of the hearing ear in the auditory system. Cochlear implantation (CI) of the deaf ear is an effective treatment for SSD. However, the newly introduced auditory input in congenital SSD often does not reach expectations in late-implanted CI recipients with respect to binaural hearing and speech perception. In a previous study, a reduction of the interaural time difference (ITD) sensitivity has been shown in unilaterally congenitally deaf cats (uCDCs). In the present study, we focused on the interaural level difference (ILD) processing in the primary auditory cortex. The uCDC group was compared with hearing cats (HCs) and bilaterally congenitally deaf cats (CDCs). The ILD representation was reorganized, replacing the preference for the contralateral ear with a preference for the hearing ear, regardless of the cortical hemisphere. In accordance with the previous study, uCDCs were less sensitive to interaural time differences than HCs, resulting in unmodulated ITD responses, thus lacking directional information. Such incongruent ITDs and ILDs cannot be integrated for binaural sound source localization. In normal hearing, the predominant effect of each ear is excitation of the auditory cortex in the contralateral cortical hemisphere and inhibition in the ipsilateral hemisphere. In SSD, however, auditory pathways reorganized such that the hearing ear produced greater excitation in both cortical hemispheres and the deaf ear produced weaker excitation and preserved inhibition in both cortical hemispheres.


Asunto(s)
Corteza Auditiva , Implantación Coclear , Señales (Psicología) , Pérdida Auditiva Unilateral , Localización de Sonidos , Gatos , Animales , Localización de Sonidos/fisiología , Pérdida Auditiva Unilateral/fisiopatología , Implantación Coclear/métodos , Corteza Auditiva/fisiopatología , Femenino , Masculino , Estimulación Acústica/métodos , Lateralidad Funcional/fisiología , Sordera/fisiopatología , Sordera/congénito , Sordera/cirugía
2.
Hear Res ; 449: 109032, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38797035

RESUMEN

Neurons within a neuronal network can be grouped by bottom-up and top-down influences using synchrony in neuronal oscillations. This creates the representation of perceptual objects from sensory features. Oscillatory activity can be differentiated into stimulus-phase-locked (evoked) and non-phase-locked (induced). The former is mainly determined by sensory input, the latter by higher-level (cortical) processing. Effects of auditory deprivation on cortical oscillations have been studied in congenitally deaf cats (CDCs) using cochlear implant (CI) stimulation. CI-induced alpha, beta, and gamma activity were compromised in the auditory cortex of CDCs. Furthermore, top-down information flow between secondary and primary auditory areas in hearing cats, conveyed by induced alpha oscillations, was lost in CDCs. Here we used the matching pursuit algorithm to assess components of such oscillatory activity in local field potentials recorded in primary field A1. Additionally to the loss of induced alpha oscillations, we also found a loss of evoked theta activity in CDCs. The loss of theta and alpha activity in CDCs can be directly related to reduced high-frequency (gamma-band) activity due to cross-frequency coupling. Here we quantified such cross-frequency coupling in adult 1) hearing-experienced, acoustically stimulated cats (aHCs), 2) hearing-experienced cats following acute pharmacological deafening and subsequent CIs, thus in electrically stimulated cats (eHCs), and 3) electrically stimulated CDCs. We found significant cross-frequency coupling in all animal groups in > 70% of auditory-responsive sites. The predominant coupling in aHCs and eHCs was between theta/alpha phase and gamma power. In CDCs such coupling was lost and replaced by alpha oscillations coupling to delta/theta phase. Thus, alpha/theta oscillations synchronize high-frequency gamma activity only in hearing-experienced cats. The absence of induced alpha and theta oscillations contributes to the loss of induced gamma power in CDCs, thereby signifying impaired local network activity.


Asunto(s)
Estimulación Acústica , Corteza Auditiva , Sordera , Ritmo Gamma , Animales , Gatos , Corteza Auditiva/fisiopatología , Sordera/fisiopatología , Sordera/congénito , Implantes Cocleares , Ritmo alfa , Potenciales Evocados Auditivos , Algoritmos , Vías Auditivas/fisiopatología , Modelos Animales de Enfermedad , Ritmo Teta
3.
Acta Otolaryngol ; 144(2): 130-135, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38634540

RESUMEN

BACKGROUND: Deaf children with cochlear nerve canal stenosis (CNCs) are always considered poor candidates for cochlear implantation. OBJECTIVES: To investigate the function of the peripheral auditory pathway in deaf children with CNCs, as revealed by the electrically evoked auditory brainstem response (EABR), and postoperative cochlear implants (CIs) outcomes. MATERIALS AND METHODS: Thirteen children with CNCs and 13 children with no inner ear malformations (IEMs) who received CIs were recruited. The EABR evoked by electrical stimulation from the CI electrode was recorded. Postoperative CI outcomes were assessed using Categories of Auditory Performance (CAP) and Speech Intelligibility Rate (SIR). RESULTS: Compared with children with no IEMs, children with CNCs showed lower EABR extraction rates, higher thresholds, a longer wave V (eV) latency and lower CAP and SIR scores. The auditory and speech performance was positively correlated with the diameter of the cochlear nerve canal and the number of channels showing wave III (eIII) and eV in children with CNCs. CONCLUSIONS AND SIGNIFICANCE: The physiological function of the peripheral auditory pathway in children with CNCs is poorer than that in children with no IEMs. Postoperative auditory and speech abilities may depend on the severity of cochlear nerve malformation and auditory conduction function.


Asunto(s)
Nervio Coclear , Sordera , Potenciales Evocados Auditivos del Tronco Encefálico , Humanos , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Masculino , Femenino , Preescolar , Nervio Coclear/fisiopatología , Nervio Coclear/anomalías , Sordera/fisiopatología , Sordera/congénito , Sordera/cirugía , Niño , Constricción Patológica , Implantación Coclear/métodos
4.
Artículo en Inglés | MEDLINE | ID: mdl-38220046

RESUMEN

Universal hearing screening offers unique possibilities for detection of congenital deafness as a consequence of congenital cytomegalovirus (CMVc) infection, so its selective study in the case of a failed test could be a non-negligible screening opportunity while other guidelines covering the possibility of universal screening are adopted. The aim of this study is to analyse the possibility of selective screening for CMVc after an altered hearing test in a regional hospital. During the period studied, the results obtained were unsatisfactory, especially in children born outside the hospital of residence, showing an excessive delay in hearing screening in many cases and in the few cases where CMVc screening could be performed, only 30% had the test ordered in a timely manner. The reasons for this are varied and the solution is to include selective screening for CMVc in the hearing screening programme. This implies shortening the timing of the hearing screening protocol to allow CMVc testing in saliva or urine (preferably) before 21 days of age and providing screening programmes with the necessary staff and time to perform it properly.


Asunto(s)
Infecciones por Citomegalovirus , Pruebas Auditivas , Tamizaje Neonatal , Humanos , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/diagnóstico , Recién Nacido , Tamizaje Neonatal/métodos , Centros de Atención Secundaria , Femenino , Sordera/congénito , Sordera/diagnóstico , Masculino
5.
Aging Cell ; 22(11): e13973, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37681746

RESUMEN

The GJB2 gene, encoding Connexin26 (Cx26), is one of the most common causes of inherited deafness. Clinically, mutations in GJB2 cause congenital deafness or late-onset progressive hearing loss. Recently, it has been reported that Cx26 haploid deficiency accelerates the development of age-related hearing loss (ARHL). However, the roles of cochlear Cx26 in the hearing function of aged animals remain unclear. In this study, we revealed that the Cx26 expression was significantly reduced in the cochleae of aged mice, and further explored the underlying molecular mechanism for Cx26 degradation. Immunofluorescence co-localization results showed that Cx26 was internalized and degraded by lysosomes, which might be one of the important ways for Cx26 degradation in the cochlea of aged mice. Currently, whether the degradation of Cx26 in the cochlea leads directly to ARHL, as well as the mechanism of Cx26 degradation-related hearing loss are still unclear. To address these questions, we generated mice with Cx26 knockout in the adult cochlea as a model for the natural degradation of Cx26. Auditory brainstem response (ABR) results showed that Cx26 knockout mice exhibited high-frequency hearing loss, which gradually progressed over time. Pathological examination also revealed the degeneration of hair cells and spiral ganglions, which is similar to the phenotype of ARHL. In summary, our findings suggest that degradation of Cx26 in the cochlea accelerates the occurrence of ARHL, which may be a novel mechanism of ARHL.


Asunto(s)
Conexina 26 , Sordera , Presbiacusia , Animales , Ratones , Cóclea/metabolismo , Conexinas/genética , Conexinas/metabolismo , Sordera/congénito , Sordera/genética , Sordera/patología , Ratones Noqueados , Presbiacusia/genética , Presbiacusia/metabolismo , Conexina 26/metabolismo
6.
Audiol Neurootol ; 28(1): 6-11, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36273454

RESUMEN

INTRODUCTION: The aim of this study was to investigate whether radiological marker(s) of the inner ear can be detected in congenital cytomegalovirus (cCMV) patients with severe-profound sensorineural hearing loss. METHODS: A retrospective imaging review of confirmed cCMV paediatric patients that had undergone consecutive cochlear implantation was performed at a tertiary hospital. Available pre- and postoperative imaging was examined, and abnormalities of the labyrinth were catalogued by a consultant neuroradiologist in the study group and control group. RESULTS: Twenty-eight paediatric patients with cCMV having undergone cochlear implantation were identified between the ages of 1-15 years (mean 4.7 years) at the time of implantation. Increased density of the vestibule on computed tomography (CT) or filling defects of the vestibule on magnetic resonance imaging (MRI) were identified in 11 and 4 patients, respectively, of the 24 in the case series. No filling defects were identified in any of the 48 CT and MRI control group. CONCLUSION: This study demonstrates a potential novel radiological finding of the inner ear of patients with cCMV. With more research, greater onus placed on MRI and CT for inner ear assessment may facilitate early detection and treatment for patients at risk of significant hearing loss. Further prospective studies in this area will help to validate radiological markers in order to establish a comprehensive inner ear classification system for neuroradiological features in cCMV.


Asunto(s)
Infecciones por Citomegalovirus , Sordera , Pérdida Auditiva Sensorineural , Vestíbulo del Laberinto , Humanos , Niño , Lactante , Preescolar , Adolescente , Citomegalovirus , Estudios Retrospectivos , Estudios Prospectivos , Sordera/congénito , Infecciones por Citomegalovirus/diagnóstico por imagen , Infecciones por Citomegalovirus/congénito , Imagen por Resonancia Magnética , Pérdida Auditiva Sensorineural/diagnóstico por imagen
7.
Int J Pediatr Otorhinolaryngol ; 155: 111086, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35219037

RESUMEN

OBJECTIVES: Age of cochlear implantation (CI) is an important predictor of language development in those with congenital sensorineural hearing loss. Despite universal newborn hearing screening initiatives and the known benefits of early CI, a subset of congenitally deaf children continue to be evaluated for cochlear implants later in childhood. This study aims to identify the barriers to early cochlear implantation in these children. METHODS: A retrospective review was conducted for all pediatric cochlear implants aged 3 years or older performed at a single academic institution between 2013 and 2017. Children implanted before the age three, those with a prior unilateral cochlear implant, and those with progressive or sudden hearing loss were excluded. Variables included newborn hearing screen results, age at hearing loss diagnosis, time of initiation and documented benefit of hearing aids, age of implantation, pre/post-implantation evaluation scores, and reason for delayed referral for cochlear implantation. RESULTS: Thirty-one patients were identified meeting these inclusion criteria. Twenty-one children were subject to UNBS in the U.S. Fourteen of those children failed their newborn hearing screening. Average age at implantation was 6.2 years. Four reasons were identified for increased age at cochlear implantation. Two categories represent delays related to (1) Amplification continually prescribed even though the range of hearing loss and speech development assessment suggests CI may have been more appropriate well before referral (N = 13) (2) Patients were not subject to newborn hearing screening and/or timely diagnosis of their hearing loss (N = 8). In other cases, patients were appropriately fit with hearing aids until evidence that they derived limited benefit and then referred for CI (N = 8). Lastly, in a few cases, records were indeterminate with regards to the timing and appropriate diagnosis of their hearing loss (N = 2). CONCLUSION: Understanding the reasons for delayed cochlear implantation in congenitally deaf children might allow the development of targeted interventions to improve outcomes. Specifically, those children who were not referred before age 3 despite use of amplification with limited benefit offer one potential target population for earlier CI.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Sordera , Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Percepción del Habla , Niño , Preescolar , Implantación Coclear/métodos , Sordera/complicaciones , Sordera/congénito , Sordera/cirugía , Pérdida Auditiva Sensorineural/complicaciones , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/cirugía , Humanos , Lactante , Recién Nacido
8.
Eur J Neurosci ; 55(6): 1629-1644, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35193156

RESUMEN

To date, the extent to which early experience shapes the functional characteristics of neural circuits is still a matter of debate. In the present study, we tested whether congenital deafness and/or the acquisition of a sign language alter the temporal processing characteristics of the visual system. Moreover, we investigated whether, assuming cross-modal plasticity in deaf individuals, the temporal processing characteristics of possibly reorganised auditory areas resemble those of the visual cortex. Steady-state visual evoked potentials (SSVEPs) were recorded in congenitally deaf native signers, hearing native signers, and hearing nonsigners. The luminance of the visual stimuli was periodically modulated at 12, 21, and 40 Hz. For hearing nonsigners, the optimal driving rate was 12 Hz. By contrast, for the group of hearing signers, the optimal driving rate was 12 and 21 Hz, whereas for the group of deaf signers, the optimal driving rate was 21 Hz. We did not observe evidence for cross-modal recruitment of auditory cortex in the group of deaf signers. These results suggest a higher preferred neural processing rate as a consequence of the acquisition of a sign language.


Asunto(s)
Sordera , Percepción del Tiempo , Corteza Visual , Sordera/congénito , Potenciales Evocados Visuales , Audición/fisiología , Humanos , Lengua de Signos
9.
Stem Cell Res ; 60: 102706, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35168097

RESUMEN

Keipert syndrome(KS, OMIM:301026) is a rare X-linked recessive inherited disorder characterized by distinctive facial appearance and digital abnormalities, and the disease is caused by hemizygous mutations in the GPC4 gene encoding the heparan sulfate proteoglycan glypican 4. We first established an induced pluripotent stem cell line (ATCi002-A) from PBMCs collected from a two-year-old boy patient with c.877 + 1G > A variant in the GPC4 gene, via reprogramming with KLF4, SOX2, OCT3/4, and c-MYC. Through identification examination, the iPSCs (ATCi002-A) stably expressed pluripotency-associated stem cell markers, and maintained a normal karyotype, and showed proliferative potential for differentiation of the three-germ layer.


Asunto(s)
Enfermedades Genéticas Ligadas al Cromosoma X , Células Madre Pluripotentes Inducidas , Deformidades Congénitas de las Extremidades Inferiores , Diferenciación Celular , Reprogramación Celular , Preescolar , China , Sordera/congénito , Enfermedades Genéticas Ligadas al Cromosoma X/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Deformidades Congénitas de las Extremidades Inferiores/metabolismo , Masculino , Mutación
10.
Clin Genet ; 101(2): 255-259, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34713892

RESUMEN

The developmental disorder Burn-McKeown Syndrome (BMKS) is characterised by choanal atresia and specific craniofacial features. BMKS is caused by biallelic variants in the pre-messenger RNA splicing factor TXNL4A. Most patients have a loss-of-function variant in trans with a 34-base pair (bp) deletion (type 1 Δ34) in the promoter region. Here, we identified two patients with BMKS. One individual has a TXNL4A c.93_94delCC, p.His32Argfs *21 variant combined with a type 1 Δ34 promoter deletion. The other has an intronic TXNL4A splice site variant (c.258-3C>G) and a type 1 Δ34 promoter deletion. We show the c.258-3C>G variant and a previously reported c.258-2A>G variant, cause skipping of the final exon of TXNL4A in a minigene splicing assay. Furthermore, we identify putative transcription factor binding sites within the 56 bp of the TXNL4A promoter affected by the type 1 and type 2 Δ34 and use dual luciferase assays to identify a 22 bp repeated motif essential for TXNL4A expression within this promoter region. We propose that additional variants affecting critical transcription factor binding nucleotides within the 22 bp repeated motif could be relevant to BMKS aetiology. Finally, our data emphasises the need to analyse the non-coding sequence in individuals where a single likely pathogenic coding variant is identified in an autosomal recessive disorder consistent with the clinical presentation.


Asunto(s)
Atresia de las Coanas/diagnóstico , Atresia de las Coanas/genética , Sordera/congénito , Genotipo , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/genética , Mutación , Ribonucleoproteína Nuclear Pequeña U5/genética , Alelos , Sitios de Unión , Sordera/diagnóstico , Sordera/genética , Facies , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Linaje , Fenotipo , Regiones Promotoras Genéticas , Unión Proteica , Empalme del ARN , Ribonucleoproteína Nuclear Pequeña U5/metabolismo , Factores de Transcripción/metabolismo
11.
Ear Hear ; 43(3): 972-983, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34772837

RESUMEN

OBJECTIVES: Hearing loss is one of the most prevalent congenital disorders among children. Many countries have implemented universal newborn hearing screening (UNHS) for the early diagnosis and treatment of hearing loss. Despite widespread implementation, the value for money of UNHS is unclear due to lack of cost and outcomes data from rigorous study designs. The objective of this research is to conduct a within-study cost-effectiveness analysis of UNHS compared with targeted screening (targeting children with risk factors of hearing loss) from the Australian healthcare system perspective. This evaluation is the first economic evaluation to assess the cost-effectiveness of UNHS compared to targeted screening using real-world data from a natural experiment. DESIGN: The evaluation assumed the Australian healthcare system perspective and considered a time horizon of 5 years. Utilities were estimated using responses to the Health Utilities Index Mark III. Screening costs were estimated based on the Victorian Infant Hearing Screening Program. Ongoing costs were estimated based on administrative data, while external data sources were used to estimate costs related to hearing services. Missing data were handled using the multiple imputation method. Outcome measures included quality-adjusted life years (QALYs) and four language and communication-related outcomes: Peabody Picture Vocabulary Test, Wechsler Nonverbal Scale of Ability, Progressive Achievement Test, and comprehensive, expressive, and total language scores based on the Preschool Language Scale. RESULTS: On average, the UNHS cost an extra Australian dollar (A$)22,000 per diagnosed child and was associated with 0.45 more QALYs per diagnosed child compared with targeted screening to 5 years, resulting in an incremental cost-effectiveness ratio (ICER) of A$48,000 per QALY gained. The ICERs for language outcomes lay between A$3,900 (for expressive language score) and A$83,500 per one-point improvement in language score (for Wechsler Nonverbal Scale of Ability). UNHS had a 69% probability of being more cost-effective compared to targeted screening at a willingness to pay threshold of A$60,000 per QALY gained. ICERs were most sensitive to the screening costs. CONCLUSIONS: The evaluation demonstrated the usefulness of a within-study economic evaluation to understand the value for money of the UNHS program in the Australian context. Findings from this evaluation suggested that screening costs were the key driver of cost-effectiveness results. Most outcomes were not significantly different between UNHS and targeted screening groups. The ICER may be overestimated due to the short follow-up period. Further research is warranted to include long-term resource use and outcome data, late diagnosis, transition and remission between severity levels, and timing of diagnosis and treatment.


Asunto(s)
Sordera , Pérdida Auditiva , Australia , Niño , Análisis Costo-Beneficio , Sordera/congénito , Audición , Pérdida Auditiva/diagnóstico , Pruebas Auditivas , Humanos , Lactante , Recién Nacido , Años de Vida Ajustados por Calidad de Vida
12.
Neural Plast ; 2021: 9957712, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34093702

RESUMEN

Congenital deafness is one of the most common causes of disability in humans, and more than half of cases are caused by genetic factors. Mutations of the MYO15A gene are the third most common cause of hereditary hearing loss. Using next-generation sequencing combined with auditory tests, two novel compound heterozygous variants c.2802_2812del/c.5681T>C and c.5681T>C/c.6340G>A in the MYO15A gene were identified in probands from two irrelevant Chinese families. Auditory phenotypes of the probands are consistent with the previously reported for recessive variants in the MYO15A gene. The two novel variants, c.2802_2812del and c.5681T>C, were identified as deleterious mutations by bioinformatics analysis. Our findings extend the MYO15A gene mutation spectrum and provide more information for rapid and precise molecular diagnosis of congenital deafness.


Asunto(s)
Sordera/genética , Miosinas/genética , Adolescente , Pueblo Asiatico , Niño , Preescolar , Biología Computacional , Sordera/congénito , Sordera/diagnóstico por imagen , Femenino , Genes Recesivos , Pruebas Genéticas , Pruebas Auditivas , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Mutación/genética , Linaje , Fenotipo , Tomografía Computarizada por Rayos X
13.
J Otolaryngol Head Neck Surg ; 50(1): 25, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33858521

RESUMEN

BACKGROUND: Salivary gland choristoma (SGCh) is a rare benign tumor reported in several unusual sites, such as the gastrointestinal tract, the optic nerve, and the internal auditory canal, but never reported in the inner ear. CASE PRESENTATION: An 8-year-old girl with a history of left profound congenital hearing loss presented to us with ipsilateral progressive severe facial nerve palsy (House-Brackmann Grade VI). The left tympanic membrane was swollen with a pulsatile tumor. Radiological investigations revealed a multilocular tumor in the inner ear extending into the middle ear and internal auditory canal (IAC). We performed a partial resection of the tumor by transmastoid approach to preserve the anatomical structure of the facial nerve. The tumor was pathologically diagnosed as SGCh. Two years after surgery, her facial function recovered to House-Brackmann Grade II and the residual tumor did not show regrowth on MRI. CONCLUSIONS: Although the natural course of this rare tumor is unknown, a partial resection is an acceptable treatment procedure when functional recovery of the facial nerve is anticipated.


Asunto(s)
Coristoma/complicaciones , Sordera/congénito , Parálisis Facial/etiología , Enfermedades del Laberinto/complicaciones , Enfermedades de las Glándulas Salivales/complicaciones , Niño , Colesteatoma del Oído Medio/complicaciones , Colesteatoma del Oído Medio/diagnóstico por imagen , Colesteatoma del Oído Medio/cirugía , Coristoma/diagnóstico por imagen , Coristoma/patología , Coristoma/cirugía , Sordera/complicaciones , Oído/diagnóstico por imagen , Femenino , Humanos , Enfermedades del Laberinto/diagnóstico por imagen , Enfermedades del Laberinto/patología , Enfermedades de las Glándulas Salivales/diagnóstico por imagen , Enfermedades de las Glándulas Salivales/patología
14.
PLoS One ; 16(4): e0249909, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33848312

RESUMEN

Congenital hearing loss affects 1 in every 1000 births, with genetic mutations contributing to more than 50% of all cases. X-linked nonsyndromic hereditary hearing loss is associated with six loci (DFNX1-6) and five genes. Recently, the missense mutation (c.1771G>A, p.Gly591Ser) in COL4A6, encoding the basement membrane (BM) collagen α6(IV) chain, was shown to be associated with X-linked congenital nonsyndromic hearing loss with cochlear malformation. However, the mechanism by which the COL4A6 mutation impacts hereditary hearing loss has not yet been elucidated. Herein, we investigated Col4a6 knockout (KO) effects on hearing function and cochlear formation in mice. Immunohistochemistry showed that the collagen α6(IV) chain was distributed throughout the mouse cochlea within subepithelial BMs underlying the interdental cells, inner sulcus cells, basilar membrane, outer sulcus cells, root cells, Reissner's membrane, and perivascular BMs in the spiral limbus, spiral ligament, and stria vascularis. However, the click-evoked auditory brainstem response analysis did not show significant changes in the hearing threshold of Col4a6 KO mice compared with wild-type (WT) mice with the same genetic background. In addition, the cochlear structures of Col4a6 KO mice did not exhibit morphological alterations, according to the results of high-resolution micro-computed tomography and histology. Hence, loss of Col4a6 gene expression in mice showed normal click ABR thresholds and normal cochlear formation, which differs from humans with the COL4A6 missense mutation c.1771G>A, p.Gly591Ser. Therefore, the deleterious effects in the auditory system caused by the missense mutation in COL4A6 are likely due to the dominant-negative effects of the α6(IV) chain and/or α5α6α5(IV) heterotrimer with an aberrant structure that would not occur in cases with loss of gene expression.


Asunto(s)
Cóclea/metabolismo , Colágeno Tipo IV/genética , Sordera/patología , Animales , Umbral Auditivo , Cóclea/química , Cóclea/diagnóstico por imagen , Cóclea/patología , Colágeno Tipo IV/deficiencia , Sordera/congénito , Sordera/genética , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación Missense , Fenotipo , Multimerización de Proteína , Microtomografía por Rayos X
16.
J Neurosci ; 41(16): 3651-3664, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33687960

RESUMEN

Cochlear implant (CI) users with a prelingual onset of hearing loss show poor sensitivity to interaural time differences (ITDs), an important cue for sound localization and speech reception in noise. Similarly, neural ITD sensitivity in the inferior colliculus (IC) of neonatally-deafened animals is degraded compared with animals deafened as adults. Here, we show that chronic bilateral CI stimulation during development can partly reverse the effect of early-onset deafness on ITD sensitivity. The prevalence of ITD sensitive neurons was restored to the level of adult-deaf (AD) rabbits in the early-deaf rabbits of both sexes that received chronic stimulation and behavioral training with wearable bilateral sound processors during development. We also found a partial improvement in neural ITD sensitivity in the early-deaf and stimulated rabbits compared with unstimulated rabbits. In contrast, chronic CI stimulation did not improve temporal coding in early-deaf rabbits. The present study is the first report showing functional restoration of ITD sensitivity with CI stimulation in single neurons and highlights the importance of auditory experience during development on the maturation of binaural circuitry.SIGNIFICANCE STATEMENT Although cochlear implants (CI) are highly successful in providing speech reception in quiet for many profoundly deaf people, CI users still face difficulty in noisy everyday environment. This is partly because of their poor sensitivity to differences in the timing of sounds arriving at the two ears [interaural time differences (ITDs)], which help to identify where the sound is coming from. This problem is especially acute in those who lost hearing early in life. Here, we present the first report that sensitivity of auditory neurons to ITDs is restored by CI stimulation during development in an animal model of neonatal deafness. These findings highlight the importance of providing early binaural auditory experience with CIs in deaf children.


Asunto(s)
Implantes Cocleares , Sordera/congénito , Sordera/terapia , Lateralidad Funcional/fisiología , Estimulación Acústica , Animales , Animales Recién Nacidos , Vías Auditivas , Fenómenos Electrofisiológicos , Femenino , Masculino , Desempeño Psicomotor , Conejos , Recuperación de la Función , Localización de Sonidos , Hueso Temporal/fisiología
17.
Acta Otolaryngol ; 141(5): 454-458, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33734006

RESUMEN

BACKGROUND: Bacteria infection and laryngopharyngeal reflux (LPR) were believed the important pathogenesis of chronic otitis media with effusion (COME). But no study researched the relationship between them on COME. AIMS: To confirm bacterial could arrive middle ear through LPR and produced acid metabolites to activate the pepsinogen of LPR causing COME. MATERIAL AND METHODS: Children (65) diagnosed COME with 122 middle ear effusions were included in COME group. Children (22) with congenital/acquired profound deafness with 22 middle ear lavage were included in CI group. Pepsin A concentration in the effusion and lavage fluid were measured. The DNA of the bacteria, IL-8 and TNF-α in the effusion were detected. RESULTS: The average concentration of pepsin A in the effusions and lavage were 176.65 ± 242.09 and 19 ng/ml. Bacterial infection rates were 75.76% and 24.24% in the pepsin A(+) and pepsin A(-) patients. In the bacterial (+), the patients of pepsin A(+) was 4.33 times higher than those of pepsin A(-). TNF-α in pepsin A(+) was higher than that in pepsin A(-). TNF-α and IL-8 were higher in bacteria(+) than those of bacteria(-). CONCLUSIONS: Bacterial infection and LPR might act in synergy in the pathogenesis of COME. SIGNIFICANCE: First time to propose LPR and bacterial infection might work synergistically to cause COME.


Asunto(s)
Infecciones Bacterianas/complicaciones , Interleucina-8/análisis , Reflujo Laringofaríngeo/complicaciones , Otitis Media con Derrame/etiología , Pepsina A/análisis , Factor de Necrosis Tumoral alfa/análisis , Adolescente , Niño , Preescolar , Enfermedad Crónica , Implantes Cocleares , Sordera/complicaciones , Sordera/congénito , Oído Medio/química , Femenino , Humanos , Masculino , Ventilación del Oído Medio , Otitis Media con Derrame/cirugía , Estudios Prospectivos
18.
Rheumatology (Oxford) ; 60(10): 4801-4810, 2021 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-33537769

RESUMEN

OBJECTIVE: To identify possible differences in baseline characteristics, initial treatment and treatment response between RA patient subgroups based on age at disease onset. METHODS: Daily practice data from the worldwide METEOR registry were used. Patients (7912) were stratified into three age-groups (age at disease diagnosis <45 years, 45-65 years, >65 years). Initial treatment was compared between the different age-groups. With Cox regression analyses the effect of age-group on time-to-switch from first to second treatment was investigated, and with linear mixed models differences in response to treatment (DAS and HAQ) between the age-groups were assessed, after correction for potential confounders. RESULTS: The >65 years age-group included more men, and more seronegative RA with somewhat higher inflammatory markers. Initial treatment choices differed only slightly between the age-groups, and the time-to-switch from initial treatment to the next was similar. DAS and HAQ improvement were dependent on the age-group, reflected by a significant interaction between age-group and outcome. The stratified analysis showed a difference of -0.02 and -0.05 DAS points and, -0.01 and 0.02 HAQ points per month in the <45 and 45-65 years age-groups as compared with the >65 year age group, a difference that did not seem clinically relevant. CONCLUSION: In this international study on worldwide clinical practice, patients with RA onset >65 years include more men and seronegative arthritis, and were initially treated slightly differently than younger patients. We observed no clinically relevant differences in timing of a next treatment step, or response to treatment measured by DAS and HAQ.


Asunto(s)
Artritis Reumatoide/patología , Adulto , Factores de Edad , Edad de Inicio , Anciano , Antiinflamatorios/uso terapéutico , Artritis Reumatoide/terapia , Sordera/congénito , Oído Externo/anomalías , Femenino , Trastornos del Crecimiento , Luxación Congénita de la Cadera , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Factores Sexuales
19.
AJNR Am J Neuroradiol ; 42(2): 377-381, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33509916

RESUMEN

BACKGROUND AND PURPOSE: Imaging is fundamental to assessing the acoustic pathway in infants with congenital deafness. We describe our depiction of the membranous labyrinth in infants using the heavily T2-weighted 3D FLAIR sequence without a contrast agent. MATERIALS AND METHODS: We retrospectively reviewed 10 infants (20 ears) (median term equivalent age: 2 weeks; IQR: 1-5 weeks) who had undergone brain MR imaging including a noncontrast heavily T2-weighted 3D FLAIR scan of the temporal bone. For each ear, 3 observers analyzed, in consensus, the saccule, the utricle, and the 3 ampullae, assessing the visibility (score 0, not appreciable; score 1, visible without well-defined boundaries; score 2, visible with well-defined boundaries) and morphology ("expected" or "unexpected" compared with adults). The heavily T2-weighted 3D FLAIR sequence was scored for overall quality (score 0, inadequate; score 1, adequate but with the presence of image degradation; score 2, adequate). RESULTS: Six (60%) MR examinations were considered adequate (score 1 or 2). The saccule was visible in 10 ears (83.3%) with an expected morphology in 9 ears (90%). In 1 ear of an infant with congenital deafness, the saccule showed an unexpected morphology. The utricle was visible as expected in 12 ears (100%). The lateral ampulla was visible in 5 ears (41.6%), the superior ampulla was visible in 6 ears (50.0%), and the posterior ampulla was visible in 6 ears (50.0%), always with expected morphology (100%). CONCLUSIONS: MR imaging can depict the membranous labyrinth in infants using heavily T2-weighted 3D FLAIR without an injected contrast agent, but the sequence acquisition time reduces its feasibility in infants undergoing MR studies during natural sleep.


Asunto(s)
Sordera/diagnóstico por imagen , Oído Interno/diagnóstico por imagen , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Medios de Contraste/administración & dosificación , Sordera/congénito , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Recién Nacido , Masculino , Estudios Retrospectivos
20.
Ear Nose Throat J ; 100(1_suppl): 38S-41S, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32320299

RESUMEN

Spontaneous cerebrospinal fluid otorrhea is very rare. Because of nonspecific symptoms, it is usually diagnosed when complications such as meningitis occur. Cerebrospinal fluid leak may be caused by cochlea malformation, which permits nonphysiological communication between subarachnoid space and tympanomastoid cavity. Nearly 20% of congenital sensorineural hearing loss is connected with inner ear bone malformation. We present a case of 40-year-old man suffering since early childhood from recurrent meningitis and right ear deafness, caused by congenital internal ear malformation. For many years, patient with sensorineural hearing loss had not undergone diagnostic radiology; computed tomography scans of the temporal bone had not been performed. Developing meningitis in early childhood was regarded as the reason for deafness.


Asunto(s)
Sordera/congénito , Oído Interno/anomalías , Pérdida Auditiva Sensorineural/congénito , Meningitis/congénito , Adulto , Humanos , Masculino , Recurrencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA