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Application of Patient-operated Otoscope in Diagnosing Patulous Eustachian Tube Dysfunction

Wed, 01 Apr 2026 00:00:00 GMT

Title: Application of Patient-operated Otoscope in Diagnosing Patulous Eustachian Tube Dysfunction Authors: Yun, Ji Min; Cheon, Tae Uk; Park, Soobin; Bae, Seong Hoon Abstract: Objective: A patulous Eustachian tube (PET) is characterized by persistent Eustachian tube patency, leading to symptoms, such as aural fullness, autophony, and audible breathing. The diagnostic criteria include both characteristic symptoms and objective findings; however, intermittent symptom presentation often prevents confirmation during clinic visits, leading to underdiagnosis. We aimed to evaluate the clinical utility of a patient-operated portable digital otoscope for confirming the diagnosis of PET. Study design: Prospective observational study. Setting: The study was conducted between January 2024 and July 2025 in a tertiary referral center. Patients: Patients with possible PET, defined by characteristic symptoms and positional improvement, but without observed tympanic membrane (TM) fluctuations during in-clinic evaluation. Intervention: Patient-operated portable digital otoscope for confirming the diagnosis of PET. Main outcome measure: Clinical utility of a patient-operated portable digital otoscope for confirming the diagnosis of PET. Results: Among 62 ears from 48 patients with possible or definite PET, 31 (50%) were initially diagnosed with definite PET. Of 24 patients (31 ears) with possible PET findings, 15 (18 ears) participated in the study. TM fluttering was detected in 8 ears in patient-operated recordings, increasing the definite PET rate from 50.0% to 62.9% (P <0.001). Conclusion: Patient-operated portable digital otoscopy significantly increased the objective confirmation of PET and addressed the diagnostic gap due to intermittent symptoms. This approach enables timely symptom-triggered TM visualization beyond clinical settings, potentially reducing diagnostic delays and unnecessary repeat visits.

A 62-aa core of the cochlin LCCL domain induces macrophage M1 polarization in vitro

Sun, 01 Mar 2026 00:00:00 GMT

Title: A 62-aa core of the cochlin LCCL domain induces macrophage M1 polarization in vitro Authors: Kim, Hyoyeol; Bae, Seong Hoon; Jang, Seung Hyun; Yoon, Soljee; Kim, Kyeonghwan; Jang, Seung Hyeon; Gee, Heon Yung; Kim, Youngsoo; Jung, Jinsei; 장승현 Abstract: BackgroundCochlin, encoded by the COCH gene, mediates innate immunity against bacterial infections by segregating pathogens and recruiting immune cells through its N-terminal LCCL domain. This domain is cleaved and secreted to attract macrophages and neutrophils, but its core motif has remained unclear.MethodsWe designed and synthesized a shortened core peptide of the LCCL domain (cLCCL; 62 amino acids) preserving the conserved structural motif. Structural stability was predicted by in silico modeling. The immunomodulatory effects of LCCL and cLCCL were evaluated in RAW264.7 macrophage cells using bulk RNA sequencing, quantitative PCR, Western blotting, flow cytometry, and immunocytochemistry.ResultsRNA sequencing in RAW264.7 cells showed that both LCCL and synthetic cLCCL peptides induced M1 polarization, with upregulation of TICAM2, CD40, and CD86. Flow cytometry demonstrated a significant increase in CD40(+)/CD86(+) M1-polarized macrophages following LCCL or cLCCL treatment, with comparable effects between the full-length and core peptides.ConclusionThe identified cLCCL appears to promote pro-inflammatory macrophage polarization, activate pro-inflammatory innate immune pathways, and warrants further evaluation in mechanistic and in vivo studies.

HAP1 interaction with KCNQ4 attenuates channel surface expression and function

Sun, 01 Mar 2026 00:00:00 GMT

Title: HAP1 interaction with KCNQ4 attenuates channel surface expression and function Authors: Kim, Jung Ah; Oh, Kyung Seok; Roh, Jae Won; Koh, Young Ik; Lin, Haiyue; Jung, Jinsei; Gee, Heon Yung Abstract: The voltage-gated channel subfamily Q member 4 (KCNQ4), a K+ channel, is one of the most frequently mutated genes in autosomal dominant nonsyndromic hearing loss. KCNQ4, which contains 6 transmembrane domains and a long cytoplasmic C-terminal tail, plays a crucial role in K+ recycling in the inner ear. Although KCNQ4 binds to various interactors, specific binding sites of the interactors remain elusive, and the biological significance of these interactions remains unknown. Therefore, this study aimed to discover a novel interactor of KCNQ4 and delineate its functional role in KCNQ4 regulation. We discovered a novel interactor of KCNQ4, huntingtin-associated protein 1 (HAP1), in addition to calmodulin, which interacts with the C-terminus of KCNQ4 using a yeast 2-hybrid assay. This interaction requires the B-segment of KCNQ4 as demonstrated by protein domain analysis. A thorough investigation of the biochemical and physiological consequences of this association revealed that HAP1 overexpression reduced surface expression and attenuated the potassium current mediated by KCNQ4. This suggests that HAP1 acts as a negative regulator of KCNQ4, potentially through the disruption of normal endocytic trafficking. These findings enhance the understanding of KCNQ4 regulation at the molecular level and highlight the potential of the HAP1-KCNQ4 axis as a target for interventions aimed at maintaining channel surface stability. (c) 2026 The Author(s). Published by Elsevier Inc. on behalf of Korean Society for Molecular and Cellular Biology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Unique characteristics of pediatric sporadic vestibular schwannoma

Sun, 01 Mar 2026 00:00:00 GMT

Title: Unique characteristics of pediatric sporadic vestibular schwannoma Authors: Shapira, Udi; Halim, Riana Kipiani Abdul; Lee, Jeong Geum; Moon, In Seok Abstract: Objective: To investigate characteristics of pediatric sporadic (non-NF2) vestibular schwannoma (VS), we compare outcomes of sporadic adult-type vestibular schwannoma which were size- and location-matched cohort. Study design: Single-institution retrospective matched case-control study. Methods: Pediatric patients (<= 21 years) with sporadic unilateral VS and >= 15 months of follow-up were identified and each matched 1:2 to adult patients (>21 years) by tumor size and location. The primary outcome was tumor control (stable vs recurrence/regrowth requiring treatment). Outcomes within the pediatric cohort were further analyzed for age-related differences. Results: Nine pediatric patients were matched to 18 adult controls. Baseline characteristics and presenting symptoms were similar. Gross total resection was achieved in 44% of children and 22% of adults (P = 0.071). Tumor control differed significantly: recurrence/regrowth occurred in 44% of children versus 6% of adults (P = 0.005). Within the pediatric group, patients with recurrence were younger (13.8 +/- 2.8 vs 17.6 +/- 2.6 years; P = 0.043). Using a 14-year cutoff, three of four recurrences (75%) occurred in children <14 years versus none in older children (P = 0.048). Conclusions: Children, particularly those under 14 years, experienced significantly poorer tumor control after surgery for sporadic VS compared with adults, despite similar tumor size and location. The higher recurrence and regrowth rates observed in the pediatric cohort suggest that a more aggressive treatment and surveillance approach may be warranted.