Detection of SARS-CoV-2 virus in middle ear effusions and its association with otitis media with effusion.

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.

Rack1 regulates cellular patterning and polarity in the mouse cochlea.

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.

A novel intronic TCOF1 pathogenic variant in a Chinese family with Treacher Collins syndrome.

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.

Microscopic Versus Endoscopic Ear Surgery for Early-Stage Glomus Tympanicum Tumors.

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.

Audiological Characteristics of Vestibular Schwannoma Patients With Normal Pure-Tone Audiometry.

OBJECTIVE: To investigate the audiological characteristics of vestibular schwannoma (VS) patients with normal pure-tone audiometry (PTA) results. STUDY DESIGN: A retrospective study. SETTING: Forty-two VS patients with normal PTA results from October 2016 to October 2022 were included. METHODS: Normal PTA was defined when the hearing threshold is ≤25 dB hearing loss (HL) in each test frequency and the PTA is ≤25 dB HL. Results of multiple audiological tests such as the auditory brainstem response (ABR), distortion product otoacoustic emission (DPOAE), multiple auditory steady-state responses threshold (ASSR), and speech discrimination score were retrospectively reviewed. Demographic data of these patients were also been collected. RESULTS: According to our results, the ABR and average ASSR threshold of the affected side were statistically significantly higher in VS patients with normal PTA. ABR waveforms on the affected side also showed more abnormalities. The DPOAE pass rates of the affected side were lower than the unaffected side while the amplitude and signal-to-noise ratio rate was also lower. In addition, we used magnetic resonance imaging 3-dimensional reconstruction images to measure the volume of tumors in these patients. We also found that higher ABR threshold means lager tumor size in patients with normal PTA. CONCLUSION: VS patients with normal PTA result cannot be assumed to have no impairment of hearing function. ABR, DPOAE, and ASSR results showed the characteristic changes in the affect ear. ABR threshold has the highest sensitivity for hearing abnormalities and is strong relative with tumor size in patients with normal PTA.

Comparison of Endoscopic Cartilage Myringoplasty in Dry and Wet Ears With Chronic Suppurative Otitis Media.

OBJECTIVES: This study compared the rate of graft success, as well as hearing improvement and dry ear time between dry ears and wet ears with otomycosis or without otomycosis in patients with chronic suppurative otitis media (CSOM) after endoscopic cartilage myringoplasty. METHODS: This retrospective study was conducted in a tertiary hospital in Shanghai. In total, 83 patients with CSOM (43 with dry ears and 40 with wet ears) were included. Among the 40 patients with CSOM and wet ears, 25 exhibited otomycosis. All patients underwent endoscopic myringoplasty, and perforations were repaired using tragal cartilage with a single-sided perichondrium. Patients were followed up for at least 6 months. Pure-tone hearing was examined preoperatively and at 3 months postoperatively. The graft uptake rate, hearing improvement, and dry ear time were compared between the groups. RESULTS: The graft success rate did not differ significantly between the dry-ear and wet-ear groups (95.35% and 90.00%, respectively). Furthermore, the graft success rate also did not differ significantly between patients with wet ears and otomycosis and those with wet ears without otomycosis (92.00% and 86.67%, respectively). Hearing gain did not differ significantly between the dry-ear and wet-ear groups. No significant difference in hearing gain was also found in patients with wet ears with or without otomycosis. However, the time to dry ear was significantly longer in the wet-ear group than in the dry-ear group. CONCLUSION: Patients with CSOM and wet ears required more time to achieve a completely healthy status. However, the graft success rate and hearing improvement were not affected by a wet middle ear and otomycosis. Thus, endoscopic myringoplasty using tragus cartilage is an effective treatment for refractory CSOM in patients with wet ears and otomycosis.

Key Genes and Endoscopic Radical Surgery in Primary Middle Ear Oncocytic Papillomas.

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.

Involvement of Dmp1 in the Precise Regulation of Hair Bundle Formation in the Developing Cochlea.

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.

Methods to Investigate Cell Polarity of Inner Ear.

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.

Rab11a Regulates the Development of Cilia and Establishment of Planar Cell Polarity in Mammalian Vestibular Hair Cells.

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 Rab11a CKO/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 1Morphological 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 Rab11a CKO/CKO animals. (G,G1,H,H1) The changes in the stereocilia morphology were more severe in Rab11a CKO/CKO /IFT 88 CKO/+ 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 Rab11a CKO/CKO , IFT88 CKO/+ mice compared to Rab11a CKO/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 ß-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.