Cadmium (Cd), a prevalent environmental contaminant, is associated with auditory dysfunction. The cochlear blood-labyrinth barrier (BLB) protects the inner ear from toxic substances, a process in which the ATP-binding cassette subfamily C member 1 protein, ABCC1, plays a critical role in expelling toxins from its cells. To understand the specific contribution of ABCC1 to Cd-induced hearing damage, we employed both an in vivo model (ABCC1 knockout mice, Abcc1 -/- mice) and an in vitro endothelial model (ABCC1-deficient human umbilical vein endothelial cells, ABCC1 -/-HUVECs). These models were exposed to CdCl2 to assess auditory responses, histopathology, BLB integrity, and oxidative stress. We also explored the NOX2-ROS/PI3K-AKT pathway using immunofluorescence, Western blotting, and RNA-seq analyses. The results indicate that ABCC1 deficiency exacerbated Cd-induced BLB leakage, promoted spiral ganglion neurons and presynaptic ribbon puncta loss, and increased ABR thresholds. In both animal and cellular models, ABCC1 deficiency enhanced NOX2 expression, ROS accumulation, and AKT dephosphorylation. Significantly, pharmacological inhibition of NOX2 with GSK2795039 attenuated oxidative stress, preserved endothelial barrier function, and partially restored PI3K-AKT signaling. These findings identify ABCC1 as a critical protector of cochlear vascular integrity during Cd exposure, acting through the NOX2-ROS/PI3K-AKT axis, and suggest its potential as a therapeutic target for preventing Cd-induced hearing loss.

BACKGROUND:Meniere's disease (MD) is a complex inner ear disorder characterized by symptoms such as vertigo, hearing loss, tinnitus, and ear fullness, significantly impacting patients' quality of life. Current diagnostic methods lack sufficient accuracy and consistency, highlighting the need for reliable segmentation tools integrated with advanced deep learning techniques. PURPOSE:To develop and evaluate the multi-stage severity assessment system (MSAS), a novel deep learning-based framework designed for precise segmentation and accurate stratification of MD severity using 2D magnetic resonance imaging (MRI). METHODS:MSAS was developed using pixel-level manual segmentation on MRI datasets from 189 patients (development cohort) and validated using an independent external test set of 70 patients. The framework integrates sequence-level prediction and slice-level segmentation, utilizing histogram of oriented gradients (HOG), support vector machine (SVM), YOLO-V5, and gradient-weighted class activation mapping (Grad-CAM) techniques. Performance was rigorously evaluated using intersection over union (IoU), dice coefficient, accuracy, mean average precision (mAP), and area under the curve (AUC) metrics. RESULTS:MSAS demonstrated strong performance, achieving an overall accuracy of 0.971 and an AUC of 0.995. Vestibular region detection yielded mean average precision (mAP) scores of 0.887 (internal set) and 0.877 (external set). For segmentation, dice coefficients were 0.940 (internal) and 0.941 (external), with consistent IoU values of 0.889 across datasets. Enhanced interpretability was achieved through slice attention maps and Grad-CAM visualizations, effectively assisting clinical decision-making. CONCLUSION:The results demonstrate the potential of deep learning techniques to enhance MD diagnosis and severity grading, offering significant clinical utility and advancing the understanding of MD's pathophysiology.

Objective:This study aimed to evaluate the diagnostic efficacy, clinical feasibility, and performance of PCR-coupled Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry（PCR-MALDI-TOF MS） in screening 20 common mutations across four deafness-associated genes in patients with non-syndromic hearing loss（NSHL）. Furthermore, it investigated the correlation between specific gene mutation types and the severity of hearing loss（genotype-phenotype correlation） was investigated. Methods:A total of 298 patients with NSHL（141 males and 157 females; age range: 3 months to 72 years） presenting to the Department of Otolaryngology Head and Neck Surgery at Xiangya Hospital, Central South University, between July, 2022, and July, 2024, were enrolled. The PCR-MALDI-TOF MS assay was employed to detect 20 hotspot mutations in four major deafness genes（GJB2 , SLC26A4 , GJB3 , and mtDNA 12S rRNA）. Sanger sequencing was used as the "gold standard" for bidirectional validation of all samples to assess performance metrics, including sensitivity, specificity, overall concordance rate, and the Kappa coefficient. Additionally, the audiometric phenotypes of patients carrying different pathogenic mutations were statistically analyzed. Results:Among the 298 subjects, pathogenic mutations were identified in 84 cases by PCR-MALDI-TOF MS, yielding a total detection rate of 28.19%. The mutation spectrum included 13 cases with homozygous variants, 42 with heterozygous variants, 16 with compound heterozygous variants, and 13 with homoplasmic mitochondrial DNA variants. The assay showed complete concordance with Sanger sequencing, with overall sensitivity, specificity, and concordance all reaching 100%. Among the 84 positive carriers, the distribution of hearing loss severity was as follows: mild（n=11）, moderate（n=20）, moderately severe（n=15）, severe（n=13）, and profound（n=25）. Notably, patients with profound hearing loss predominantly carried SLC26A4 mutations（13/25） and GJB2 mutations（8/25）, while those with severe hearing loss were primarily associated with SLC26A4 mutations（7/13）. Conclusion:The PCR-MALDI-TOF MS technology demonstrates high accuracy, sensitivity, and specificity, making it an ideal tool for rapid first-line screening of common deafness gene hotspots in the Chinese population. This study reveals a significant association between GJB2 truncating mutations and SLC26A4 splice site mutations with severe-to-profound hearing loss phenotypes. These findings suggest that early genetic diagnosis is crucial for predicting auditory prognosis and guiding timely clinical intervention for patients with these specific genotypes.

Objectives This study aimed to determine whether there are differences of cerebrospinal fluid pressure (CSF-P) on patients with Ménière’s disease (MD) during different phases. Methods Noninvasive CSF-P measurement was performed using MRI with a fat-suppressed fast recovery fast spin echo T2-weighted sequence, with the optic nerve subarachnoid space width (ONSASW) posterior to the globe serving as an indicator. Endolymphatic hydrops (EH) grades and hearing thresholds were analysed to investigate the potential correlations with CSF-P. Results A total of 66 participants were included. At the location of 3 mm behind the globe, the ONSASW and CSF-P were significantly smaller in the acute phase of MD group compared to both the remission phase of MD group (p < 0.001, p = 0.005, respectively) and control group (p < 0.001, p = 0.043, respectively). No statistically significant differences were found between the remission phase of MD group and the control group (both p > 0.05). Statistically significant correlation between CSF-P and hearing threshold was exclusively observed during the acute phase, with a correlation coefficient of 0.479 (p = 0.024). No significant associations between CSF-P and EH grades in both the two MD groups (all p > 0.05). Conclusion The study suggests that patients with MD experience a reduction in intracranial pressure during acute episodes, and these fluctuations may indicate hearing threshold variations in early-stage of patients.

Objectives Branchio-oto syndrome (BOS) is an autosomal dominant disorder characterized by multiple system anomalies, typically sparing the kidneys. BOS exhibits considerable clinical heterogeneity and ethnic variability; most studies have been conducted in European populations rather than in Asian populations, and its prevalence is approximately 1 in 40,000. EYA1 is the most commonly implicated gene in BOS, with mutations ranging from missense to frameshift, splicing, and nonsense variants. Although splicing mutations are important contributors to the disease, previous research has paid less attention to novel mutations that cause aberrant RNA splicing and their pathogenic mechanisms. Furthermore, reproductive interventions aimed at preventing disease transmission have not been reported. Methods We collected samples from a three-generation Chinese family affected by BOS. Whole exome sequencing was used to screen for candidate causative genes. A minigene assay was performed to identify aberrant splicing products, and additional molecular biology techniques were employed to analyze the pathogenicity of the resulting mistranslated proteins. Preimplantation genetic testing (PGT), based on single-nucleotide polymorphism analysis, was utilized to prevent hearing loss in this family. Results Whole-exome sequencing identified a novel mutation, EYA1:c.1598-2AG>TA, which was classified as pathogenic according to American College of Medical Genetics and Genomics criteria. The minigene assay verified aberrant RNA splicing that is predicted to result in premature termination of EYA1 protein translation. Cytological experiments demonstrated that the truncated EYA1 protein is unstable, exhibits impaired nuclear translocation, and fails to interact properly with SIX1. PGT enabled the proband to give birth to a healthy boy. Conclusion We identified a novel splicing variant in the EYA1 gene and elucidated its potential molecular pathogenic mechanism through several functional experiments. Based on these findings, we successfully implemented PGT to ensure the birth of a healthy offspring free from BOS.

To investigate the diagnostic performance of dual-layer spectral detector CT (DLCT) in differentiating middle ear cholesteatoma and chronic suppurative otitis media (CSOM). This prospective, institutional review board-approved study consecutively enrolled patients with suspected middle ear cholesteatoma or CSOM from January to July 2024. All participants underwent DLCT scanning before surgery. Clinical average hearing threshold (AHT) was collected. Four blinded readers, with 2, 3, 11, and 13 years of experience, independently provided diagnoses, based on high-resolution CT (HRCT) or HRCT combined spectral images (integrated mode). Virtual mono-energetic images (VMIs) at 40 keV, spectral attenuation slope (λHU), and effective atomic number (Zeff) were measured. Intraoperative or pathological findings served as reference standards. Receiver operating characteristic (ROC) curve analysis was used. Sixty-six participants (median age, 47.0 [33.0–55.0] years; 23 men, 33 with cholesteatoma) were included. The sensitivity of the integrated mode was 87.9

Hearing loss is the most prevalent disabling disease. Cochlear implantation（CI） serves as the primary intervention for severe to profound hearing loss. This consensus systematically explores the value of genetic diagnosis in the pre-operative assessment and efficacy prognosis for CI. Drawing upon domestic and international research and clinical experience, it proposes an evidence-based medicine three-tiered prognostic classification system（Favorable, Marginal, Poor）. The consensus focuses on common hereditary non-syndromic hearing loss（such as that caused by mutations in genes like GJB2, SLC26A4, OTOF, LOXHD1） and syndromic hereditary hearing loss（such as Jervell & Lange-Nielsen syndrome and Waardenburg syndrome）, which are closely associated with congenital hearing loss, analyzing the impact of their pathological mechanisms on CI outcomes. The consensus provides recommendations based on multiple round of expert discussion and voting. It emphasizes that genetic diagnosis can optimize patient selection, predict prognosis, guide post-operative rehabilitation, offer stratified management strategies for patients with different genotypes, and advance the application of precision medicine in the field of CI.

BACKGROUND:The γ-actin protein, encoded by the ACTG1 gene, is a critical cytoskeletal component in non-muscle cells. Mutations in ACTG1 are associated with autosomal dominant, progressive sensorineural hearing loss (HL), but clinical heterogeneity remains poorly understood. METHODS:We identified a novel missense variant, c.981C>G (p.Ile327Met; I327M), in a Chinese family with hereditary HL through whole exome sequencing. Functional analyses were performed to assess ACTG1 mRNA and protein expression, F-actin organisation and subcellular localisation. Structural modelling and electrostatic analysis were used to predict the impact of the I327M substitution. Additionally, we reviewed 35 published ACTG1-related families involving 82 patients to explore genotype-phenotype correlations. RESULTS:The I327M variant resulted in significantly reduced ACTG1 transcript and protein levels, accompanied by disrupted F-actin integrity in patient-derived peripheral blood mononuclear cells. Structural modelling suggested that the variant alters the electrostatic environment near the tropomyosin-binding interface, potentially compromising filament stability. Literature review and comparative analysis revealed that variants located within actin-binding protein (ABP) interaction sites were associated with an earlier onset and more severe progression of HL compared with those located outside ABP-binding domains. CONCLUSION:The c.981C>G (p.Ile327Met) variant contributes to HL pathogenesis through dual mechanisms involving impaired gene expression and filament destabilisation. This study highlights the clinical relevance of variant location relative to ABP binding regions and provides new insights into genotype-phenotype relationships in ACTG1-associated HL.

Objective:To summarize the initial experience and evaluate the technical feasibility of the endo-scopic transcanal transpromontorial approach(TTA)for vestibular schwannoma resection by analyzing long-term follow-up outcomes.Methods:A retrospective analysis was conducted on the perioperative and long-term follow-up data(mean follow-up time:5 years)of patients who underwent endoscopic TTA for vestibular schwannoma re-section in the Department of Otorhinolaryngology Head and Neck Surgery at Xiangya Hospital,Central South University,between January 2020 and December 2020.Long-term outcomes were systematically evaluated.Re-sults:This study included two patients(one 41-year-old male and one 51-year-old female).According to the AAO-HNS hearing classification system,preoperative hearing was Class C in one patient and Class D in the other.Pre-operative imaging confirmed Koos stage Ⅰ tumors in both cases.Postoperative transient facial nerve paralysis(House-Brackmann Grade Ⅲ)recovered to Grade Ⅰ within 4 months.No complications such as cerebrospinal flu-id leakage,intracranial infection,or intracranial hemorrhage occurred.No tumor recurrence was observed during the 5-year follow-up period.Conclusion:The endoscopic transcanal transpromontorial approach is minimally inva-sive,facilitates rapid recovery,and demonstrates satisfactory technical feasibility and safety when strict patient se-lection criteria(Koos stage Ⅰ tumors with non-serviceable hearing)are applied.

自2015年以来,中国逐步引入并实施现代耳内镜手术.在过去10年中,耳内镜手术现已成为耳科领域的重要治疗手段.随着技术的不断进步,耳内镜手术的应用范畴持续拓展,优势逐渐获得广泛认可,手术器械的革新与手术方法的创新交相辉映,使得耳内镜手术的效率大幅提高,安全性也得到了显著增强.本期圆桌会议我们邀请了国内耳内镜外科领域卓有建树的中青年专家,共同回溯耳内镜手术在中国的发展历程,分享宝贵的实际应用经验,并深入探讨其未来的发展方向.

Meniere's disease (MD) is an inner ear disease characterized by endolymphatic hydrops (EH). Maintaining a regular daily routine is crucial for MD patients. However, the relationship between circadian rhythms and MD remains unclear. Therefore, we investigated the effect of circadian rhythm on endolymphatic hydrops and its underlying mechanisms. Mice with endolymphatic hydrops were subjected to chronic jet lag (CJL) conditions to simulate the MD patients under circadian rhythm disruptions. We assessed whether this disruption would exacerbate inner ear damage with endolymphatic hydrops. RNA-seq of the inner ear and bioinformatic analysis were performed. Then, the expression of PER2, AQP2, AQP4, AQP5, and BDNF were assessed, and the morphological changes were evaluated in the inner ear. Our findings showed circadian rhythm disruption affected the cochlear internal clock genes in the inner ear, particularly in mice with EH. EH mice under CJL conditions exhibited exacerbated hearing impairment and an increased severity of EH. GO enrichment analysis revealed that the regulation of fluid homeostasis and neurotransmitter release at synapses were significantly enriched. Disruption of circadian rhythms disturbed the expression pattern of PER2, reduced BDNF levels, and affected the expression of aquaporins in the cochlea. Moreover, the disruption of circadian rhythm compromised inner hair cell synapses and auditory nerve fibers. This study indicated that disruption of circadian rhythms may exacerbate inner ear damage in endolymphatic hydrops mice by affecting the aquaporins and compromising synapses and auditory nerves in the inner ear. BDNF and PER2 may play a central role in these pathophysiological processes.

OBJECTIVE:This study reports a novel heterozygous, likely truncating mutation in the diaphanous homolog 1 (DIAPH1) gene associated with non-syndromic hearing loss. METHODS:Family members underwent audiological and imaging assessments, whole-exome sequencing (WES), and Sanger sequencing. RESULTS:Sensorineural hearing loss was observed in all five individuals, with severity ranging from mild to severe. None of the affected patients reported vestibular complaints, and routine blood tests showed normal platelet counts. Whole-exome sequencing (WES) revealed a novel frameshift variation, c.3555delA (p.Gln1185Hisfs*3), in exon 26 of the DIAPH1 gene. This variation co-segregated with the hearing-impaired phenotype in the family. The data collected support the classification of c.3555delA as a genetic etiology of hereditary hearing loss according to the American College of Medical Genetics and Genomics guidelines. CONCLUSION:We identified a novel pathogenic mutation in the DIAPH1 gene, thereby expanding the mutation spectrum associated with hearing loss.

Waardenburg Syndrome (WS) is a rare genetic disorder that leads to congenital hearing loss and pigmentation defects. Microphthalmia-associated transcription factor (MITF) is one of its significant pathogenic genes. Despite the comprehensive investigation in animal models, the pathogenic mechanism is still poorly described in humans due to difficulties accessing embryonic tissues. In this work, we used induced pluripotent stem cells derived from a WS patient carrying a heterozygous mutation in the MITF gene c.626A>T (p.His209Leu), and differentiated toward melanocyte lineage, which is the most affected cell type involved in WS. Compared with the wild-type cell line, the MITFmut cell line showed a reduced expression of the characteristic melanocyte-related genes and a lesser proportion of mature, fully pigmented melanosomes. The transcriptome analysis also revealed widespread gene expression changes at the melanocyte stage in the MITFmut cell line. The differentially expressed genes were enriched in melanogenesis and cell proliferation-related pathways. Interestingly, ion transport-related genes also showed a significant difference in MITFmut-induced melanocytes, indicating that the MITF mutant may lead to the dysfunction of potassium channels and transporters produced by intermediate cells in the cochlea, further causing the associated phenotype of deafness. Altogether, our study provides valuable insights into how MITF mutation affects WS patients, which might result in defective melanocyte development and the related phenotype based on the patient-derived iPSC model.

OBJECTIVES:The first purpose of this study was to ascertain the distribution of unilateral Ménière's disease (MD) clinical subgroups in China and compare with the population reported in Europe and the United States. The second purpose was to investigate the effectiveness in different clinical phenotypes. METHODS:Participants were categorised into one of five subtypes using a previously reported classification scheme based on cluster analysis. The distribution and clinical characteristics were analysed and compared with the two cohorts reported in Europe and the United States. Participants were followed up to observe the therapeutic effectiveness over a 2-year period. RESULTS:A total of 245 patients diagnosed with UMD were enrolled in the study, with 84 of these participants providing complete and detailed follow-up data. All of the unilateral MD patients were accurately classified: 58.0% were classic MD, 25.7% were delayed MD, 1.2% was familial MD, 12.7% were sporadic MD with migraine and 2.4% were autoimmune MD. Our findings revealed a significant difference in the distribution between this cohort and the European cohort. Follow-up assessments revealed worse vertigo control rate in the patients with migraine compared to the classical MD (50.0% vs. 82.6%, p = 0.034). CONCLUSION:The distribution of unilateral MD subtypes in this Chinese population differs from that in the European population, and the therapeutic effectiveness varies across subtypes in this cohort. Our study highlights the importance of the clinical heterogeneity in unilateral MD, and further studies are needed to identify the optimal interventions for specific subgroups.

The underlying mechanisms of lead exposure-induced cochlear spiral ganglion neurons (SGNs) injury are not yet clear. This study explored whether ferroptosis is involved in lead-induced SGNs injury and investigated the mechanism of lead-induced iron overload in SGNs. A primary culture cell model of lead acetate-induced SGNs damage was established. The changes in levels of iron ions, reactive oxygen species, lipid peroxides, and glutathione in SGNs were measured after lead acetate intervention and ferroptosis inhibitors pre-treatment. The morphology of mitochondria was also observed, and the expression of ferroptosis marker genes glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11), as well as iron metabolism-related proteins transferrin receptor protein 1 (TFR1), nuclear receptor coactivator 4 (NCOA4), heme oxygenase-1 (HO-1), and ferroportin (FPN) were detected. Results showed that lead acetate exposure induced SGNs injury in a time- and dose-dependent manner. Intracellular iron accumulation, increased levels of reactive oxygen species and lipid peroxide with decreased level of antioxidant capacity were occurred in SGNs after lead exposure. Meanwhile, decreased expressions of GPX4 and SLC7A11 and increased expressions of iron metabolism-related proteins (TFR1, NCOA4, and HO-1) were also found. Lead acetate intervention also caused mitochondrial shrinkage with blurred and fragmented morphology. Pre-treatment with ferroptosis inhibitors (Fer-1 and DFOM) significantly ameliorated lead-induced SGNs injury. In summary, lead exposure can induce ferroptosis in SGNs, the antioxidant defense system and iron metabolism disorder are involved in lead-induced SGNs ferroptosis. Thus, inhibiting ferroptosis may be a new strategy for preventing and treating lead exposure-related hearing loss.

With the development of the social economy, we are exposed to increasing noise in our daily lives. Our previous work found an ABCC1(NM_004996.3:c.A1769G, NP_004987.2:p.N590S) variant which cosegregated with the patients in an autosomal dominant non-syndromic hearing loss family. At present, the specific mechanism of deafness caused by ABCC1 mutation is still not clear. Using the knock-in mouse model simulating human ABCC1 mutation, we found that the occurrence of family-related phenotypes was likely attributed to the combination of the mouse genotype and low-intensity noise. GSH and GSSG are important physiological substrates of ABCC1. The destruction of GSH-GSSG balance in the cochleae of both Abcc1 N591S/+ mice and Abcc1 N591S/N591S mice during low-intensity noise exposure may result in irreversible damage to the hair cells of the cochleae, consequently leading to hearing loss in mice. The findings offered a potential novel idea for the prevention and management of hereditary hearing loss within this family.

Objective:To study the feasibility and efficacy of using a tympanic cartilage shaping device in endoscopic type Ⅰ tympanoplasty. Methods:A tympanic cartilage shaper was designed and manufactured by measuring tympanic membrane dimensions with HRCT imaging for cutting and shaping cartilage to repair the tympanic membrane. From August 2019 to October 2021, 66 patients（72 ears） with chronic suppurative otitis media in Xiangya Hospital underwent endoscopic type Ⅰ tympanoplasty with this tympanic cartilage shaping device, and were observed the tympanic membrane healing and hearing recovery effect after surgery. Postoperative follow-up ranged from 3-24 months, with an average of 9 months. The data were analyzed by the SPSS 26.0 software. Results:According to the imaging measurements, tympanic pars tensa width（8.60±0.20） mm, height（8.64±0.19） mm, design and manufacture a cylindrical cartilage shaping device with inner diameter 8.60 mm. After tympanoplasty, the healing rate of tympanic membrane was 100%; The average air-bone gap before surgery was（23.10±7.33） dB, then（14.30±6.40） dB 1 month after surgery, which were significant reduced compared with those before surgery. The average air-bone gap was（14.30±6.40） dB 3 month after surgery compared with 1 month after surgery, the difference was also statistically significant（t=6.630, P<0.05）. Conclusion:The tympanic membrane cartilage shaper shaping cartilage in endoscopic tympanoplasty is simple, stable and reliable, which can reduce the time of graft cartilage processing, improve the efficiency of surgery, and restore the tympanic membrane morphology and function in the postoperative period.

The ABCC1 gene belongs to the ATP-binding cassette membrane transporter superfamily, which plays a crucial role in the efflux of various endogenous and exogenous substances. Mutations in ABCC1 can result in autosomal dominant hearing loss. However, the specific roles of ABCC1 in auditory function are not fully understood. Through immunofluorescence, we found that ABCC1 was expressed in microvascular endothelial cells (ECs) of the stria vascularis (StV) in the murine cochlea. Then, an Abcc1 knockout mouse model was established by using CRISPR/Cas9 technology to elucidate the role of ABCC1 in the inner ear. The ABR threshold did not significantly differ between WT and Abcc1-/- mice at any age studied. After noise exposure, the ABR thresholds of the WT and Abcc1-/- mice were significantly elevated. Interestingly, after 14 days of noise exposure, ABR thresholds largely returned to pre-exposure levels in WT mice but not in Abcc1-/- mice. Our subsequent experiments showed that microvascular integrity in the StV was compromised and that the number of outer hair cells and the number of ribbons were significantly decreased in the cochleae of Abcc1-/- mice post-exposure. Besides, the production of ROS and the accumulation of 4-HNE significantly increased. Furthermore, StV microvascular ECs were cultured to elucidate the role of ABCC1 in these cells under glucose oxidase challenge. Notably, 30 U/L glucose oxidase (GO) induced severe oxidative stress damage in Abcc1-/- cells. Compared with WT cells, the ROS and 4-HNE levels and the apoptotic rate were significantly elevated in Abcc1-/- cells. In addition, the reduced GSH/GSSG ratio was significantly decreased in Abcc1-/- cells after GO treatment. Taken together, Abcc1-/- mice are more susceptible to noise-induced hearing loss, possibly because ABCC1 knockdown compromises the GSH antioxidant system of StV ECs. The exogenous antioxidant N-acetylcysteine (NAC) may protect against oxidative damage in Abcc1-/- murine cochleae and ECs.