Background Temporal bone computed tomography (CT) helps diagnose chronic otitis media (COM). However, its interpretation requires training and expertise. Artificial intelligence (AI) can help clinicians evaluate COM through CT scans, but existing models lack transparency and may not fully leverage multidimensional diagnostic information. Objective We aimed to develop an explainable AI system based on 3D convolutional neural networks (CNNs) for automatic CT-based evaluation of COM. Methods Temporal bone CT scans were retrospectively obtained from patients operated for COM between December 2015 and July 2021 at 2 independent institutes. A region of interest encompassing the middle ear was automatically segmented, and 3D CNNs were subsequently trained to identify pathological ears and cholesteatoma. An ablation study was performed to refine model architecture. Benchmark tests were conducted against a baseline 2D model and 7 clinical experts. Model performance was measured through cross-validation and external validation. Heat maps, generated using Gradient-Weighted Class Activation Mapping, were used to highlight critical decision-making regions. Finally, the AI system was assessed with a prospective cohort to aid clinicians in preoperative COM assessment. Results Internal and external data sets contained 1661 and 108 patients (3153 and 211 eligible ears), respectively. The 3D model exhibited decent performance with mean areas under the receiver operating characteristic curves of 0.96 (SD 0.01) and 0.93 (SD 0.01), and mean accuracies of 0.878 (SD 0.017) and 0.843 (SD 0.015), respectively, for detecting pathological ears on the 2 data sets. Similar outcomes were observed for cholesteatoma identification (mean area under the receiver operating characteristic curve 0.85, SD 0.03 and 0.83, SD 0.05; mean accuracies 0.783, SD 0.04 and 0.813, SD 0.033, respectively). The proposed 3D model achieved a commendable balance between performance and network size relative to alternative models. It significantly outperformed the 2D approach in detecting COM (P≤.05) and exhibited a substantial gain in identifying cholesteatoma (P<.001). The model also demonstrated superior diagnostic capabilities over resident fellows and the attending otologist (P<.05), rivaling all senior clinicians in both tasks. The generated heat maps properly highlighted the middle ear and mastoid regions, aligning with human knowledge in interpreting temporal bone CT. The resulting AI system achieved an accuracy of 81.8% in generating preoperative diagnoses for 121 patients and contributed to clinical decision-making in 90.1% cases. Conclusions We present a 3D CNN model trained to detect pathological changes and identify cholesteatoma via temporal bone CT scans. In both tasks, this model significantly outperforms the baseline 2D approach, achieving levels comparable with or surpassing those of human experts. The model also exhibits decent generalizability and enhanced comprehensibility. This AI system facilitates automatic COM assessment and shows promising viability in real-world clinical settings. These findings underscore AI’s potential as a valuable aid for clinicians in COM evaluation. Trial Registration Chinese Clinical Trial Registry ChiCTR2000036300; https://www.chictr.org.cn/showprojEN.html?proj=58685

Background Treacher Collins syndrome (TCS; OMIM 154500) is a craniofacial developmental disorder. Methods To investigate the genetic features of a four-generation Chinese family with TCS, clinical examinations, hearing tests, computed tomography, whole-exome sequencing (WES), Sanger sequencing, reverse transcription (RT)-PCR, and the Minigene assay were performed. Results The probands, an 11-year-old male and his cousin exhibited typical clinical manifestations of TCS including conductive hearing loss, downward slanting palpebral fissures, and mandibular hypoplasia. Computed tomography revealed bilateral fusion of the anterior and posterior stapedial crura and malformation of the long crura of the incus. WES of both patients revealed a novel heterozygous intronic variant, i.e., c.4342 + 5_4342 + 8delGTGA (NM_001371623.1) in TCOF1 . Minigene expression analysis revealed that the c.4342 + 5_4342 + 8delGTGA variant in TCOF1 caused a partial deletion of exon 24 (c.4115_4342del: p.Gly1373_Arg1448del), which was predicted to yield a truncated protein. The deletion was further confirmed via RT-PCR and sequencing of DNA from proband blood cells. A heterozygous variant in the POLR1C gene (NM_203290; exon6; c.525delG) was found almost co-segregated with the TCOF1 pathogenic variant. Conclusions In conclusion, we identified a heterozygous TCOF1 splicing variant c.4342 + 5_4342 + 8delGTGA (splicing) in a Chinese TSC family with ossicular chain malformations and facial anomalies. Our findings broadened the spectrum of TCS variants and will facilitate diagnostics and prognostic predictions.

Intense noise poses a threat to spiral ganglion neurons (SGNs) in the inner ear, often resulting in limited axonal regeneration during noise injury and leading to noise-induced hearing loss (NIHL). Here, we propose an ultrasound-triggered nitric oxide (NO) release to enhance the sprouting and regeneration of injured axons in SGNs. We developed hollow silicon nanoparticles to load nitrosylated N-acetylcysteine, producing HMSN-SNO, which effectively protects NO from external interferences. Utilizing low-intensity ultrasound stimulation with bone penetration, we achieve the controlled release of NO from HMSN-SNO within the cochlea. In mice with NIHL, a rapid and extensive loss of synaptic connections between hair cells and SGNs is observed within 24 h after exposure to excessive noise. However, this loss could be reversed with the combined treatment, resulting in a hearing functional recovery from 83.57 to 65.00 dB SPL. This positive outcome is attributed to the multifunctional effects of HMSN-SNO, wherein they scavenge reactive oxygen species (ROS) to reverse the pathological microenvironment and simultaneously upregulate the CREB/BDNF/EGR1 signaling pathway, thereby enhancing neuroplasticity and promoting the regeneration of neuronal axons. These findings underscore the potential of nanomedicine for neuroplasticity modulation, which holds promise for advancing both basic research and the further treatment of neurological diseases.

A large-scale outbreak of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) occurred in Shanghai, China, in early December 2022. To study the incidence and characteristics of otitis media with effusion (OME) complicating SARS-CoV-2, we collected 267 middle ear effusion (MEE) samples and 172 nasopharyngeal (NP) swabs from patients. The SARS-CoV-2 virus was detected by RT-PCR targeting. The SARS-CoV-2 virus, angiotensin-converting enzyme 2 (ACE2), and transmembrane serine protease 2 (TMPRSS2) expression in human samples was examined via immunofluorescence. During the COVID-19 epidemic in 2022, the incidence of OME (3%) significantly increased compared to the same period from 2020 to 2022. Ear symptoms in patients with SARS-CoV-2 complicated by OME generally appeared late, even after a negative NP swab, an average of 9.33 +/- 6.272 days after COVID-19 infection. The SARS-CoV-2 virus was detected in MEE, which had a higher viral load than NP swabs. The insertion rate of tympanostomy tubes was not significantly higher than in OME patients in 2019-2022. Virus migration led to high viral loads in MEE despite negative NP swabs, indicating that OME lagged behind respiratory infections but had a favorable prognosis. Furthermore, middle ear tissue from adult humans coexpressed the ACE2 receptor for the SARS-CoV-2 virus and the TMPRSS2 cofactors required for virus entry.

Purpose: Glomus tympanicum tumors are benign primary tumors of the middle ear that can be completely removed using modern surgery. We compared endoscopic ear surgery (EES) to traditional microscopic ear surgery (MES) in terms of the removal of early-stage glomus tympanicum tumors. Methods: We retrospectively reviewed 25 cases treated from 2003 to 2021 that were of Grade I or II based on the Glasscock–Jackson classification system. Overall, 18 cases underwent MES: 8 via trans-tympanic bone and 10 via canal-wall-down or canal-wall-up tympanomastoidectomy (CWDT or CWUT) and 7 underwent EES. We compared surgery durations, the lengths and costs of hospitalization, postoperative complications, and relapse rates between the two groups and among the three specific operation ways. Results: The postoperative follow-up period ranged from 1 to 19 years. There was no between-group difference in operative time or the length or cost of hospitalization. Operative time and cost of hospitalization did not show a statistically significant correlation to the three surgical procedures, whereas it was found that the group of MES via the trans-tympanic bone had shorter length of hospitalization when compared with CWUT or CWDT group. All tumors were completely resected; pulsatile tinnitus improved in all patients, and there was no major complication. Two patients who underwent CWUT or CWDT (one each) relapsed; no patient relapsed in the EES group. Conclusion: MES via the trans-tympanic bone and EES via the ear canal safely and reliably remove early-stage tumors without excessive patient discomfort.

Objectives: To explore the risk factors of early postoperative taste disturbance (EPTD) after type I endoscopic tympanoplasty and operative modification strategies to improve taste disturbance. Methods: This was a controlled study. One hundred and twenty-four patients who underwent type I endoscopic tympanoplasty with tragal cartilage graft were separated evenly into control and modified groups. The full-thickness tragus cartilage graft was placed close to the bony annulus to ensure drum integrity in the control group, and in the modified group, the cartilage graft was not in contact with the posterior-superior bony annulus, and the inferior-posterior of the scutum. Univariate and multivariate models were used to analyze the possible factors affecting EPTD and the prognosis of taste recovery. Results: The incidence of EPTD was significantly lower in the modification group (24.19%) than in the control group (56.45%) (OR: 4.24, 95% CI: 1.93-9.33, P < .001). Surgical manipulation of the chorda tympani nerve resulted in a higher incidence of EPTD (OR: 2.43; 95% CI: 1.06-5.57, P = .035). The size of the graft did not affect taste disturbance. No difference in the taste recovery rate was observed between the control and test groups (Z = -1.57, P = .116) after 3 months. The recovery rate of patients with manipulated chorda tympani nerves was still lower than that of patients without at 3 months (Z = -2.74, P = .006). Conclusion: Modified surgery and reduced manipulation of the chorda tympani nerve effectively reduce EPTD. Manipulated chorda tympani nerves may have a persistent effect on taste recovery.

The cochlea hair cells transform mechanic sounds to neural signals with a remarkable sensitivity and resolution. This is achieved via the precisely sculpted mechanotransduction apparatus of the hair cells and the supporting structure of the cochlea. The shaping of the mechanotransduction apparatus, the staircased stereocilia bundles on the apical surface of the hair cells, requires an intricate regulatory network including planar cell polarity (PCP) and primary cilia genes in orienting stereocilia bundles and building molecular machinery of the apical protrusions. The mechanism linking these regulatory components is unknown. Here, we show that a small GTPase known for its role in protein trafficking, Rab11a, is required for ciliogenesis in hair cells during development in mice. In addition, in the absence of Rab11a, stereocilia bundles lost their cohesion and integrity, and mice are deaf. These data indicate an essential role of protein trafficking in the formation of hair cell mechanotransduction apparatus, implicating a role of Rab11a or protein trafficking in linking the cilia and polarity regulatory components with the molecular machinery in building the cohesive and precisely shaped stereocilia bundles.

Dentin matrix protein 1 (Dmp1) is a highly phosphorylated, extracellular matrix protein that is extensively expressed in bone and teeth but also found in soft tissues, including brain and muscle. However, the functions of Dmp1 in the mice cochlea are unknown. Our study showed that Dmp1 was expressed in auditory hair cells (HCs), with the role of Dmp1 in those cells identified using Dmp1 cKD mice. Immunostaining and scanning electron microscopy of the cochlea at P1 revealed that Dmp1 deficiency in mice resulted in an abnormal stereociliary bundle morphology and the mispositioning of the kinocilium. The following experiments further demonstrated that the cell-intrinsic polarity of HCs was affected without apparent effect on the tissue planer polarity, based on the observation that the asymmetric distribution of Vangl2 was unchanged whereas the Gαi3 expression domain was enlarged and Par6b expression was slightly altered. Then, the possible molecular mechanisms of Dmp1 involvement in inner ear development were explored via RNA-seq analysis. The study suggested that the Fgf23-Klotho endocrine axis may play a novel role in the inner ear and Dmp1 may regulate the kinocilium-stereocilia interaction via Fgf23-Klotho signaling. Together, our results proved the critical role of Dmp1 in the precise regulation of hair bundle morphogenesis in the early development of HCs.

Objective: To investigate the technique and efficacy of fully endoscope resection of intralabyrinthine schwannomas (ILS) by transcanal transpromontorial endoscopic approach (TTEA). Study Design: Retrospective case review. Setting: Hospital. Patients: All patients who were affected by ILS, without extension to the internal auditory canal and underwent surgery with TTEA in our hospital in 2020. Intervention(s): Therapeutic. Main Outcome Measure(s): Recovery status, postoperative complications and remaining symptoms after surgery. Results: Three patients were included, all of which underwent gross total resections. The follow-up period was from 10 months to 2 years. No intraoperative and postoperative major complications were observed. There was no facial paralysis or cerebrospinal fluid leakage postoperatively. The hospitalization time of TTEA was 5 days. Three patients' vertigo was relieved after 1 week without receiving vestibular therapy. Only 1 patient complained of transient episodes of vertigo when climbing or holding heavy objects. Conclusions: TTEA has the advantages of clear vision to identify the anatomical structure, enabling complete tumor resection, reduced operation time, and faster postoperative recovery.Level of Evidence: IV

耳内镜外科是通过外耳道进行中耳和颞骨疾病的诊断和治疗,因其微创性和较好的听力重建效果受到了越来越多医师的肯定.本文结合国内外耳内镜外科研究的最新文献以及笔者使用耳内镜技术处理耳部罕见病例的心得,探讨耳内镜外科的临床应用适应证以及今后的发展方向.

Objective Papillomas originating from the Schneiderian epithelium within the middle ear are extremely rare and may be associated with a high rate of recurrence and malignant transformation. Oncocytic papillomas represent the rarest pathological subtype of such tumors. The current investigation aimed to determine whether there exists a distinct mechanism underlying the incidence of oncocytic papillomas arising primarily within the middle ear, and to explore potential treatment strategies to ensure complete removal and prevent recurrence. Study Design Search of the English literature for cases of middle ear papilloma and RNA sequencing analysis of three samples from one new case presenting at the Eye and ENT Hospital, Fudan University (Shanghai, China), with recurrent middle ear oncocytic papilloma, along with two normal mucosal samples. Setting Academic, tertiary referral hospital. Patient and interventions The patient underwent open mastoidectomy and endoscopic tympanoplasty twice in 6 years. Histopathology confirmed oncocytic papilloma in middle ear. The patient has been free of the disease at 18 months of follow-up without radiation, whereas the RNA-seq analysis of the samples in endoscopic operations remained nonmalignant. Results Only four cases of primary middle ear oncocytic papillomas have been reported. Recurrent masses usually originate from around the eustachian tube, which may explain the pathogenesis of this lesion. RNA-seq analysis was used to identify 1,317 (UP, 239; DOWN, 1078) differentially expressed genes between papillomas and normal mucosa. The involvement of some hub proteins (e.g., FN1, CXCL8, L10, JUN, and FOS) in the pathogenesis of primary middle ear papillomas was found to align with the observed clinical features. Conclusion The middle ear oncocytic papillomas were extremely rare and remained incompletely understood. The findings of this first RNA-seq analysis of this rare tumor may serve to enhance comprehension of and aid in the management of middle ear papillomas.

COPYRIGHT © 2022 Sun, Chen, Sun, Li and Ren. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Editorial: The mechanism on development and regeneration of inner ear hair cells

Rack1 features seven WD40 repeats that fold into a multifaceted scaffold used to build signaling complexes in a context-dependent manner. Previous in vitro studies have revealed associations between Rack1 and many other proteins. Rack 1 is required for establishing planar cell polarity (PCP) in zebrafish and Xenopus. However, any molecular role of Rack1 in protein complexes or polarity regulation remains unclear. Here, we show that Rack1 is an essential gene in mice. Conditional knockout of Rack1 shortened the cochlear duct and induced cellular patterning defects characteristic of defective convergent extension (this PCP process is mediated by cellular junctional remodeling in the developing cochlear epithelium). Also, cochlear hair cells were no longer uniformly oriented in Rack1 conditional knockout mutants. Rack1 was enriched in the cellular cortices of sensory hair cells. In Rack1-deficient cochleae, E-cadherin expression at the cellular boundaries was greatly reduced. Together, the findings reveal a molecular role of Rack1 in PCP signaling that likely involves modulation of E-cadherin levels at the adherens junctions of the plasma membrane.

Objective: To identify the typical pattern of changes of vestibular-evoked myogenic potentials (VEMPs) and explore the relationship between VEMPs and the anthropometry factors in patients with obstructive sleep apnea (OSA).Methods: Patients diagnosed as OSA after overnight polysomnography (PSG) tests were enrolled as the study group. Healthy volunteers were recruited as the control group. Anthropometry data of the body shape and VEMPs results were collected completely. The correlation analysis was conducted among those parameters.Results: Forty-nine patients with OSA who were diagnosed in the Therapy Center of Sleep-disordered Breathing in our hospital and sex-and age-matched healthy controls as well. Significant changes in ocular and cervical VEMPs (oVEMP and cVEMP) in the study group were observed, which were reduced response rates, elevated thresholds, decreased amplitudes, and prolonged first wave latencies. In oVEMP, the first wave (n1) latency was significantly correlated with weight, body mass index (BMI), neck circumference, waist circumference, hip circumference, and apnea hypopnea index (AHI). In a tentative application, combined use of BMI and oVEMP n1 latency increased the detection rate during OSA screening prior to PSG.Conclusion: OSA can negatively affect function of otolithic organs and their pathways. The first wave latency of the VEMPs waveform may be another important parameter to define peripheral nervous system lesions caused by systemic diseases as OSA.(c) 2022 Elsevier B.V. All rights reserved.

Hair cells in cochlea and vestibular organs depend on the coordinated cell polarity to perform the normal auditory or balance function. The mouse inner ear is one of the ideal model to study planar cell polarity. In this chapter, we introduce a series of general experimental methods for studying planar cell polarity in the inner ear. The approaches presented here are also applicable to other organs with particular polarity phenotypes.

ObjectiveThis study aimed to explore how obstructive sleep apnea (OSA) affects the function of each vestibular organ and to identify the correlations among them.MethodsA prospective study was conducted involving 32 healthy controls and 64 patients with OSA. The objective detection methods of the utricle and saccule are vestibular-evoked myogenic potentials (VEMPs). A combination of the caloric test and video head impulse test (vHIT) was used to comprehensively evaluate the objective function of semicircular canals.ResultsElevated thresholds (p < 0.001), decreased waveform amplitudes (p < 0.001), prolonged first wave latencies (p < 0.001), and shortened first interpeak latencies (p < 0.001) were observed in both ocular VEMP (oVEMP) and cervical VEMP (cVEMP). A significant difference was found in the caloric test comparison (χ2 = 4.030, p = 0.045) but not in the vHIT. The intergroup comparison of normal rates among the VEMPs, caloric test, and vHIT groups showed a significant difference (p < 0.001).ConclusionThe impairment of vestibular function in patients with OSA was uneven and biased. More attention should be given to vestibular dysfunction in the diagnosis and treatment of OSA.

Journal of Cellular PhysiologyVolume 236, Issue 7 p. i-i COVER Cover Image, Volume 236, Number 7, July 2021 Xiaoqing Qian, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorZiyu He, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorYanmei Wang, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorBinjun Chen, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorAlisa Hetrick, Research Service, VA Loma Linda Healthcare System, Loma Linda, California, USASearch for more papers by this authorChunfu Dai, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorFanglu Chi, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorHongzhe Li, Corresponding Author Hongzhe.Li@va.gov orcid.org/0000-0003-0207-5367 Research Service, VA Loma Linda Healthcare System, Loma Linda, California, USA Department of Otolaryngology—Head and Neck Surgery, Loma Linda University School of Medicine, Loma Linda, California, USA Correspondence Hongzhe Li, Research Service, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA. Email: Hongzhe.Li@va.gov Dongdong Ren, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, No. 83, Fenyang Rd, Xuhui, Shanghai 200031, China. Email: Dongdongren@fudan.edu.cnSearch for more papers by this authorDongdong Ren, Corresponding Author Dongdongren@fudan.edu.cn orcid.org/0000-0002-2889-9375 ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, China Correspondence Hongzhe Li, Research Service, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA. Email: Hongzhe.Li@va.gov Dongdong Ren, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, No. 83, Fenyang Rd, Xuhui, Shanghai 200031, China. Email: Dongdongren@fudan.edu.cnSearch for more papers by this author Xiaoqing Qian, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorZiyu He, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorYanmei Wang, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorBinjun Chen, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorAlisa Hetrick, Research Service, VA Loma Linda Healthcare System, Loma Linda, California, USASearch for more papers by this authorChunfu Dai, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorFanglu Chi, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, ChinaSearch for more papers by this authorHongzhe Li, Corresponding Author Hongzhe.Li@va.gov orcid.org/0000-0003-0207-5367 Research Service, VA Loma Linda Healthcare System, Loma Linda, California, USA Department of Otolaryngology—Head and Neck Surgery, Loma Linda University School of Medicine, Loma Linda, California, USA Correspondence Hongzhe Li, Research Service, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA. Email: Hongzhe.Li@va.gov Dongdong Ren, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, No. 83, Fenyang Rd, Xuhui, Shanghai 200031, China. Email: Dongdongren@fudan.edu.cnSearch for more papers by this authorDongdong Ren, Corresponding Author Dongdongren@fudan.edu.cn orcid.org/0000-0002-2889-9375 ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China NHC Key Laboratory of Hearing Medicine (Fudan University), Shanghai, China Correspondence Hongzhe Li, Research Service, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA. Email: Hongzhe.Li@va.gov Dongdong Ren, ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, No. 83, Fenyang Rd, Xuhui, Shanghai 200031, China. Email: Dongdongren@fudan.edu.cnSearch for more papers by this author First published: 12 April 2021 https://doi.org/10.1002/jcp.30395AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Abstract Front Cover: The cover image is based on the Original Research Article Hair cell uptake of gentamicin in the developing mouse utricle by Xiaoqing Qian et al., https://doi.org/10.1002/jcp.30228. Volume236, Issue7July 2021Pages i-i RelatedInformation

Intratympanic injection of gentamicin has proven to be an effective therapy for intractable vestibular dysfunction. However, most studies to date have focused on the cochlea, so little is known about the distribution and uptake of gentamicin by the counterpart of the auditory system, specifically vestibular hair cells (HCs). Here, with a combination of in vivo and in vitro approaches, we used a gentamicin-Texas Red (GTTR) conjugate to investigate the mechanisms of gentamicin vestibulotoxicity in the developing mammalian utricular HCs. In vivo, GTTR fluorescence was concentrated in the apical cytoplasm and the cellular membrane of neonatal utricular HCs, but scarce in the nucleus of HCs and supporting cells. Quantitative analysis showed the GTTR uptake by striolar HCs was significantly higher than that in the extrastriola. In addition, the GTTR fluorescence intensity in the striola was increased gradually from 1 to 8 days, peaking at 8-9 days postnatally. In vitro, utricle explants were incubated with GTTR and candidate uptake conduits, including mechanotransduction (MET) channels and endocytosis in the HC, were inhibited separately. GTTR uptake by HCs could be inhibited by quinine, a blocker of MET channels, under both normal and stressed conditions. Meanwhile, endocytic inhibition only reduced GTTR uptake in the CoCl2 hypoxia model. In sum, the maturation of MET channels mediated uptake of GTTR into vestibular HCs. Under stressed conditions, MET channels play a pronounced role, manifested by channel-dependent stress enhanced GTTR permeation, while endocytosis participates in GTTR entry in a more selective manner.

Vestibular organs have unique planar cell polarity (Figure 1A), and their normal development and function are dependent on the regular polarity of cilia (Figure 1B) requires. Rab11a is a small G protein that participates in the transportation of intracellular and extracellular materials required for polarity formation; however, our understanding of the mechanisms of the actions of Rab11a in vestibular organs is limited. Here, we showed that the general shape of the utricle was abnormal in Rab11aCKO/CKO mice. These mice also showed abnormal morphology of the stereocilia bundles, which were reduced in both length and number, as well as disturbed tissue-level polarity. Rab11a affected the distribution of polarity proteins in the vestibular organs, indicating that the normal development of cilia requires Rab11a and intraflagellar transportation. Furthermore, small G protein migration works together with intraflagellar transportation in the normal development of cilia. FIGURE 1 Morphological changes of stereocilia in the extrastriolar hair cells from Rab11a single or Rab11a/IFT88 double-mutant utricles. (A) Medial view of a mouse left inner ear with its five vestibular sensory organs (gray). Enlarged are the utricle showing their subdivisions, LPR (yellow line), and striola (blue). LES, lateral extrastriola; MES, medial extrastriola; LPR, line of polarity reversal. (B) Schematic view of vestibular hair cell. Kinocilium is marked with ace-tubulin. Basal body is marked with γ-tubulin. (C,C1,D,D1) Normal appearance of the stereocilia of extrastriolar hair cells of wild-type controls. (E,E1,F,F1) Altered morphology in Rab11aCKO/CKO animals. (G,G1,H,H1) The changes in the stereocilia morphology were more severe in Rab11aCKO/CKO/IFT 88CKO/+ mice. (I–L) Higher magnification of confocal images of hair cells. (M–P) Scanning electron microscopy images of hair cells from wild-type controls and Rab11a mutants. (I,M) Morphology of normal. hair cells of wild-type controls. (J,N) The number of stereocilia on a single hair cell was deceased in the Rab11a mutant. (K,O) Stereocilia were shorter in mutants compared to the wild-type controls. (L,P) The staircase-like hair bundle architecture of hair cells was lost in Rab11a mutant mice. (Q) The percentage of hair cells with abnormal development of static cilia bundles in the extrastriola region was counted as a percentage of the total (n = 5). The percentage of abnormal hair cells was higher in Rab11aCKO/CKO, IFT88CKO/+ mice compared to Rab11aCKO/CKO. The abnormal ratios of single and double knockout hair cells were 42.1 ± 5.7 and 71.5 ± 10.4, respectively. In (A–J), for all primary panels, hair cell stereociliary bundles were marked with phalloidin (green), the actin-rich cuticular plate of hair cells was labeled with β-spectrin (red), while the basal body of the hair cell was labeled with γ-tubulin (blue). Scale bars: 10 μm (C–H1), 5 μm (J–N). *P < 0.05.

OBJECTIVES:To identify genes that are related to delayed endolymphatic hydrops (DEH) in patients by RNA-Seq analysis.DESIGN:Observational study.SETTING:Eye & ENT Hospital, Fudan University (Shanghai, China).PARTICIPANTS:We collected the entire vestibular system from four patients with DEH who underwent labyrinthectomy. Three control samples were collected from patients with acoustic neuroma or facial neuroma treated via the translabyrinthine approach. High-throughput RNA-Seq analysis was performed to investigate gene expression in the pathological vestibular system.MAIN OUTCOME MEASURES:Our bioinformatic analysis identified 17 genes that were upregulated and eight genes that were downregulated in patients with DEH compared with the controls.RESULTS:The altered gene expression profile suggested that DEH is closely related to neuropathy and autoimmune disease. In addition, many of the differentially regulated genes were involved in cell adhesion, suggesting a role of cell adhesion in DEH. Immunofluorescence analysis confirmed the expression of PMP2 and CLDN19 in the cytoplasm of hair cells and scattered expression of MPZ at cell junctions. The protein expression levels were higher in specimens from patients with Ménière's disease and DEH compared with controls.CONCLUSIONS:The protein expression profile of vestibular organs in patients with endolymphatic hydrops exhibited a degree of similarity to that of Ménière's disease. Endolymphatic hydrops is characterised by autoimmune abnormalities. DEH and Ménière's disease are likely to be different manifestations of the same disease, with disparate clinical symptoms. RNA-Seq is a useful analytical tool to characterise the vestibular pathology based on its transcriptome.