Otitis media with effusion (OME) is a prevalent pediatric condition, yet its molecular mechanisms remain incompletely understood. The NLRP3 inflammasome is known to regulate inflammation in various diseases, but its role in OME remains unclear. This study aimed to investigate NLRP3 activation in OME using both a murine model and clinical samples. Experimental OME was induced in mice via intratympanic injection of lipopolysaccharide (LPS). On day 3 postinduction, middle ear tissues and lavage fluid were collected. Nlrp3 mRNA expression was assessed by qPCR, while cleaved caspase-1 and mature IL-1β protein levels were evaluated by western blotting. IL-1β levels in lavage fluid and serum were measured via ELISA. Human middle ear effusions (MEE) and matched serum samples were collected from pediatric OME patients, and concentrations of IL-1β and IL-18 were measured and normalized to total protein. To assess the functional role of NLRP3, OME was induced in Nlrp3 knockout ( Nlrp3-/- ) and wild-type (WT) mice, followed by otoscopic and histologic evaluation. LPS-induced OME mice exhibited increased expression of NLRP3, cleaved caspase-1, and IL-1β. ELISA confirmed elevated IL-1β in middle ear lavage fluid. In human samples, IL-1β and IL-18 were significantly higher in MEE than in serum. Nlrp3-/- mice showed reduced IL-1β production but no significant differences in histopathology or effusion resolution compared with WT. NLRP3 inflammasome contributes to local inflammation in OME but does not significantly alter disease progression, suggesting involvement of additional inflammatory pathways.

Introduction Otic organoids differentiated from human pluripotent stem cells are three-dimensional in vitro cultures that broadly mimic the complexity and functionality of the human inner ear. They provide a valuable model for developmental and disease-related studies. However, current protocols differ substantially in efficiency and reproducibility. In this study, we investigated whether different stem cell maintenance media influence the differentiation of keratinocyte-derived induced pluripotent stem cells (kiPSCs) into the otic lineage. Methods Keratinocyte-derived iPSCs were cultured in either a self-made FTDA medium or the commercially available PeproGrow™ hESC medium and subsequently subjected to an established otic differentiation protocol. Early developmental stages, including the pre-placodal region, the otic placode, and pro-neural sensory regions, were analysed using immunofluorescence and gene expression profiling. Results While no significant differences were observed in iPSC maintenance or pluripotency between the two media, distinct differences emerged during otic differentiation. Media composition influenced the expression of placodal, otic, and pro-sensory markers at multiple stages, indicating differential responsiveness to otic induction cues. Conclusion Our findings demonstrate that stem cell maintenance media composition is a critical determinant of subsequent otic lineage differentiation. These results provide guidance for optimizing stem cell culture conditions and improving the reproducibility of otic organoid differentiation protocols.

Abstract: In today’s Digital world efficiency of audio is important, In this Project we get reduced file size while maintaining the quality preceived by the human ear. we implemented audio compression using Algorithm in Python which decreases file sizes, maintaining preceived sound quality. Our method uses perceptual coding, transform coding, entropy coding and deep learning. this results in practical, efficient, and scalable audio compression.

Establishment of a human inner ear model reveals that gentamicin C2b is substantially less ototoxic than clinical gentamicin.

Whole-ear finite element analysis of superior semicircular canal dehiscence and its impact on inner-ear responses.

The sound of silence: Sex and individual differences in rat ultrasonic vocalisation.

Since human inner ear hair cells do not regenerate, the current treatments of hereditary deafness depend on hearing aids or cochlear implant. However, uncovering the functions of genes responsible for hereditary hearing loss is not only useful for their diagnosis but also for developing therapies. The pathogenetic mechanism of human non-syndromic deafness DFNB77 without morphological defects in the inner year caused by LOXHD1 mutations is not fully understood. We introduced zebrafish because the lateral line hair cells are structurally and physiologically similar to the human inner ear hair cells and mutations involved in non-symptomatic hearing loss can be assessed by their swimming behavior. The knock-out (KO) of LOXHD1b gene which is expressed in the lateral line hair cells was generated using the CRISPR-Cas9 system in zebrafish, and its morphological and functional changes were evaluated. As with human patients the LOXHD1b KO zebrafish larvae did not exhibit detectable morphological defects, but showed prolonged water flow sensing time. These results suggest that LOXHD1b plays pivotal roles for the hair cell neural activity and its KO zebrafish mutant serves as a useful model for revealing the molecular mechanisms linking LOXHD with hair cell function and for a drug screening to rescue the swimming phenotype.

Metformin (Met), a highly hydrophilic drug, exhibits anti-inflammatory and regenerative effects beyond its antidiabetic role. However, its extreme polarity limits passive diffusion through the stratum corneum, necessitating optimized formulations for effective transdermal delivery. This study compared Met permeability through human and porcine ear skin using three lotion formulations containing different permeation enhancers: (1) 6% Met + glycerol (Gly); (2) 6% Met + Gly and propylene glycol (PG); and (3) 10% Met + PG and Transcutol® (PG + T). In human skin, Gly and PG formulations showed minimal permeation, whereas PG + T markedly increased cumulative permeation and flux, confirming the critical role of Transcutol®. Porcine skin displayed consistently higher permeability across all formulations (Gly < PG < PG + T), indicating that it may overestimate human permeability to hydrophilic drugs. Despite limited transdermal flux, Gly- and PG-based lotions produced measurable Met accumulation within the epidermis and dermis, suggesting potential for topical use. Overall, these results emphasize the importance of enhancer selection—particularly Transcutol®—in improving dermal delivery of hydrophilic compounds and caution against relying solely on porcine skin as a human surrogate.

Introduction: Anthropometric measurements of the external ear provide valuable normative data for applications in clinical practice, reconstructive surgery, forensics, and ergonomics. As ear morphology varies by population, sex, and age, population-specific reference data are essential. This study aimed to determine the normal dimensions of the outer ear among adult patients. Methods: A cross-sectional study was conducted from 8th to 28th September 2025 among 157 adult patients (82 males and 75 females) visiting the hospital with normal external ears. Standardized auricular measurements, including auricular height, auricular width, lobular height, and lobular width, were obtained bilaterally using a digital vernier caliper following established anthropometriclandmarks. Data were analyzed using descriptive statistics to calculate the mean and standard deviation. Results: The mean right and left auricular heights were 63.38 ± 6.19 mm and 63.13 ± 6.49 mm, respectively, while auricular widths were 33.81 ± 6.26 mm (right) and 33.82 ± 6.23 mm (left). Minimal bilateral asymmetry was observed. Males exhibited greater auricular height and width, whereas females showed marginally larger lobular dimensions. Lobular height demonstrated greater variability than width across both sexes. Conclusions: The study revealed strong bilateral symmetry in external ear measurements, with clear sexual dimorphism—males having larger auricular dimensions and females slightly larger lobules. These findings provide baseline data for Nepalese adults and hold relevance in forensic identification, prosthetic design, and reconstructive surgery. Further large-scale, multiethnic studies are recommended to validate and expand upon these findings.

This study introduces a real-time shaping noise control approach for kitchen hoods using the filtered-E least mean square (FELMS) algorithm-based active noise control (ANC) system. The goal is to not only lower the noise effectively but also make the remaining sound more pleasant to human ears. Two existing noise control methods, including the filtered-X LMS (FxLMS) based, and the output-error filtered-U recursive LMS (OE-FURLMS) based ANC systems were compared. Both the amount of noise reduction and the sound quality measurement using five key factors: loudness, sharpness, roughness, tonality, and overall pleasantness were measured to evaluate performance. The test results show that the proposed system reduces kitchen hood noise effectively, spreads the noise reduction more evenly across different frequencies, and creates a sound that people find more pleasant compared to the traditional methods.

Rolling bearings are crucial in rotating machinery, and combining natural and characteristic frequencies improves fault detection. However, natural frequencies face challenges like feature extraction difficulties and drift, necessitating resonance peak information supplementation. Existing methods for extracting resonance peaks often struggle with low quality, false peaks, and merging issues. This paper introduces a novel resonance peak extraction method based on auditory saliency (RESAS), inspired by the human auditory system. RESAS combines Gammatone filtering, multi-scale Gaussian filtering, and lateral inhibition to simulate auditory attention and efficiently extract resonance peaks. A resonance peak saliency map(RPSP) is generated, from which features are extracted and used as input to an improved random forest model(TF-RF) for fault classification. Tests on the QPZZ-II Fault Simulation Test Bench and KWCU data show that the method effectively identifies bearing faults at various speeds and loads, demonstrating its strong potential for application. Furthermore, due to its broadband characteristics and capacity to excite the system's natural frequencies, this method has potential for scalability to other impact-type fault systems.

Meniere’s disease (MD), a degenerative inner ear disorder, is characterized by debilitating episodic vertigo and hearing fluctuations, progressing to permanent sensory impairment. The prevailing dogma attributes these symptoms to abnormal inner ear fluid buildup—endolymphatic hydrops (EH)—with pressure rise and repetitive microtrauma to sensory epithelia. However, this pressure-based mechanism lacks direct experimental evidence and fails to explain key clinical aspects. To revisit EH, we performed 3D reconstructive, machine-learning-enhanced histological analyses and immunohistochemistry on postmortem human inner ear specimens. Contrary to the classic pressure-based theory, EH-affected epithelia showed neither increased spacing between neighboring cells nor morphological evidence of ruptures; instead, they exhibited a 4–7-fold increase in epithelial cell number (hyperplasia) in Reissner’s and saccular membranes, present in both early and advanced EH. Quantification of hyperplastic epithelial surface area and immunolocalization of fluid homeostasis-associated proteins suggest this hyperplasia may compensate for cell loss in the endolymphatic sac, a key MD site. These findings challenge the view of EH as purely a pressure phenomenon, revealing epithelial expansion consistent with a coordinated compensatory response to preserve fluid homeostasis and function. This paradigm shift introduces dual beneficial and detrimental roles for EH, suggesting new therapies that promote tissue repair while preventing maladaptive remodeling.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-24549-9.

Recent single-cell transcriptomic approaches are uncovering the breadth and depth of cell diversity within the mammalian inner ear. Macrophages, detected from fetal week 5 in the human inner ear, persist into adulthood and yet remain poorly understood in terms of their origin and function. Using self-generated and public scRNA-seq data, we identified seven distinct macrophage subtypes spanning fetal weeks 7.5 to 16.4 and adulthood. Each macrophage subtype is linked to specific developmental stages and displays a unique gene expression profile. These findings corroborate earlier histological evidence of resident and non-resident macrophages in both the developing and adult human cochlea. We also showed that the human inner ear is seeded by macrophages from both embryonic and more definitive sources, corroborating studies in mice. By analyzing ligand–receptor interactions, we highlight potential macrophage contributions to inner ear organogenesis. This research provides new insights into the diverse roles of human inner ear macrophages.

Ear infections are the most common bacterial infection among young children and the leading cause of healthcare visits and antibiotic prescriptions. This study explores the connection between the microbiome of the nose-the community of microorganisms that live in different areas of the human body-and recurrent ear infections in young children. An analysis of nasal swabs collected from 58 children over a year showed that as children age, they tend to have fewer bacterial pathogens and more species that are associated with a healthy state in their microbiomes. These more mature microbiomes were associated with fewer ear infections. In contrast, recent use of antibiotics was associated with microbiomes that had more bacterial pathogens and that were associated with greater ear infection incidence. Overall, these findings indicate that the microbiome may be a key factor in reduced ear infections as children age.

The objective of this research is to determine how hydroxyapatite (HA) coating affects the functioning of middle ear prostheses when they are exposed to normal sound levels. We applied 90 dB of sound pressure to a finite element model of the human ear at frequencies ranging from 250 to 8000 Hz. We looked stress and displacement changed in the Z direction for three materials: Ti25Nb25Zr, Bonecement and PLA, both with and without HA coating. Ti25Nb25Zr had the most stable mechanical behavior, with low stress in the range of 2E-09 MPa and micro-motion approximately. The coating made it even better with comparison of materials cited. The results show that HA coating enhances the mechanical stability of the material, particularly in Ti25Nb25Zr, making it the most suitable material for rebuilding the middle ear.

Augmented reality in the operating room enhances surgical precision. Merging information from preoperative 3D imaging into the real-time video during surgery allows for better visualization of critical structures. Displaying an augmented real-time video on a screen requires a 2D/3D to 2D image registration as a preliminary step. An accurate error estimation is crucial for evaluating the system's performance. A reprojection error estimation has been commonly calculated based on a pinhole camera model, which does not accurately represent the optical properties of an endoscope or an operative microscope. In our work, a system for registering a CT-scan to a 2D-otoendoscopic video was evaluated. This system was designed for use in an augmented reality setup for ear surgery. Evaluation was performed using the target registration reprojection error measurement. A comparison between the pinhole camera model and the thin-lens model was conducted. Additionally, a quantification formula for the target registration reprojection error was established and the parameters affecting it were analyzed. Specifically, the target's distance from the camera lens and its angle of alignment with the optical axis were assessed. Five human ear resin models bearing spherical Markers with their corresponding CT-scans were used. The estimated error with the thin-lens model was 0.65 ± 0.52 mm versus 0.79 ± 0.60 mm with the pinhole model (18% of difference). Target registration reprojection error tended to be correlated to the distance from the camera lens. In conclusion, both the target-lens distance and the target alignment influence the target registration reprojection error measurement. The choice of the optical model affects significantly the error estimation, and the thin-lens model should be preferred in endoscopic applications. Based on the results, the tested augmented reality system is compatible with ear surgery.

Computational models, particularly finite-element (FE) models, are essential for interpreting experimental data and predicting system behavior, especially when direct measurements are limited. Tuning these models is particularly challenging when a large number of parameters are involved. Traditional methods, such as sensitivity analyses, are time-consuming and often provide only a single set of parameter values, focusing on reproducing averaged trends rather than capturing experimental variability. New approaches are needed to make computational models more adaptable to patient-specific clinical applications. We applied simulation-based inference (SBI) using neural posterior estimation (NPE) to tune an FE model of the human middle ear against subject-specific data. The training dataset consisted of 10,000 FE simulations of stapes velocity, ear-canal input impedance, and absorbance, paired with seven FE parameter values sampled within plausible ranges. By using simulated data, we generated a diverse training dataset, enabling efficient learning by the neural network (NN). The NN learned the association between parameters and simulation outcomes, providing a probability distribution of parameter values, which could be used to produce subject-specific computational inferences. By accounting for noise and test–retest variability, the method provided a probability distribution of parameters, rather than a single set, fitting three experimental datasets simultaneously. Importantly, examining the inferred parameter distributions alongside prior knowledge of normal ranges enables individualized differential inference used for diagnosis. SBI offers an objective alternative to sensitivity analyses, uncovering parameter interactions, supporting personalized diagnosis and treatment, and compensating for limited clinical training data. This method is applicable to any computational model, enhancing its potential for improved patient outcomes.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-22164-2.

The human ear can detect sounds ranging from 0 to 120 dB; however, prolonged exposure to higher levels may cause severe hearing damage and affect the nervous system. Therefore, it is essential to implement preventive measures in industrial settings, where occupational diseases related to noise continue to rise due to the lack of effective corrective actions. This study aimed to evaluate auditory capacity impairment in workers exposed to occupational noise in a plastics industry during 2024. A quantitative methodology with a descriptive, correlational, and cross-sectional approach was used. The sampling was non-probabilistic and purposive. Audiometric evaluations and sound pressure level measurements were conducted on a total of 64 workers. Results showed that 85.5% of the sample were male workers exposed to noise, with a small percentage presenting mild to moderate hearing loss. In the extrusion, trimming, and production control areas, workers maintained normal hearing; however, in the printing, sealing, and grinding areas, a significant percentage exhibited mild to moderate hearing loss. The sealing and trimming areas complied with noise level regulations, whereas the printing and extrusion areas presented hazardous sound levels for auditory health. In conclusion, prolonged exposure to noise levels above permissible limits was significantly associated with hearing deterioration in workers (r = -0.266; p = 0.034), confirming noise as a cumulative occupational risk factor.

Uncomfortable ear pressure during vehicle door closure is associated with enhanced vehicle airtightness and an unreasonable reduction in cabin noise. Current computational simulation methods for ear pressure, however, suffer from low accuracy and inefficiency. In this study, we propose a porous medium model to represent the dynamic airflow resistance characteristics of the pressure relief valve, which improves both the efficiency and accuracy of precise ear pressure simulation. Additionally, an optimized sound insulation cover design is shown to effectively improve ear comfort. Using the overset mesh technique in STAR-CCM+, a transient in-vehicle flow field model was established. Model parameters were calibrated experimentally, and the optimization scheme was validated through combined simulation and experimental data. Results demonstrate that removing the silencer cover of the pressure relief valve reduces the peak ear pressure at the third-row right seat by 20%, with all simulation errors at the human ear remaining below 8%. Compared to the traditional fixed-opening model, the porous medium approach significantly improves the accuracy of simulating the actual pressure relief process. The dynamic pressure relief model and the optimized sound insulation cover effectively enhance ear pressure comfort, offering theoretical guidance for balancing door closing sound quality and vehicle sealing performance in automotive engineering.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-19758-1.

BackgroundThe external human ear is a polymorphic and polygenic structure with individual uniqueness, making it a valuable target in forensic DNA phenotyping (FDP) studies. Previous genome-wide association studies have identified multiple genetic loci associated with variation in ear characteristics. However, research focused on predicting ear morphology within the context of FDP remains limited. This study aimed to develop DNA-based predictive models for external ear morphology in the Chinese population.MethodsDigital photographs of 675 volunteers were used to score 13 ear phenotypes, each categorized into three levels. Multinomial logistic regression (MLR) was applied for genetic association analysis. Five predictive models—MLR, support vector machines, random forest, AdaBoost, and k-nearest neighbors—were developed and evaluated using 10-fold cross-validation.ResultsGenetic association analysis identified several influential single-nucleotide polymorphism (SNPs) for each ear phenotype. Among the five models, AdaBoost and MLR demonstrated superior performance, achieving area under the curve (AUC) values above 0.7 for predicting absent tragus cases (level_0). To simplify classification, binary models incorporating genetic interactions were constructed for absent tragus cases. Specifically, the AdaBoost model achieved an AUC of 0.74, while the binary logistic regression (BLR) model reached an AUC of 0.72.ConclusionsThese findings highlight the potential forensic application of genetic markers in predicting ear morphology within the Chinese population, contributing to the advancement of FDP research and practice.