Changes in Otitis Media During COVID-19.

OBJECTIVES: During the COVID-19 pandemic, various non-pharmaceutical interventions such as individual hygiene practices like hand washing, social distancing, and mandates for the use of masks in public spaces were implemented to reduce the spread of the disease. Otitis media (OM) is a common infectious disease. How the changed environment due to the COVID-19 pandemic has influenced the prevalence of infectious diseases like OM is not known. This study aimed to investigate how OM prevalence and trends changed during COVID-19 in Korea. METHODS: OM patient data from 2017 to 2021 were extracted from the Health Insurance Review and Assessment Service database. Patients diagnosed with disease code H66 (suppurative and unspecified otitis media) were selected for analysis. Data on OM prevalence, gender, region, medical institution, and number of ventilating-tube prescriptions were analyzed. All age groups were included, and ages were categorized into 5-year ranges. RESULTS: The number of patients diagnosed with the OM disease code decreased continuously from 2017 to 2021 (1 598 205, 1 560 178, 1 520 948, 983 701, and 734 901). The average OM prevalence per 1000 persons decreased by 45.0% from 30.2 in 2017 to 2019 to 16.6 in 2020 to 2021. The change of OM prevalence was greater for the 0 to 5 age group than other age groups. The decrease in average prevalence per 1000 persons was greatest in the 0 to 5 age group (48.6% decrease from 358.2 in 2017-2019 to 184.1 in 2020-2021). The impact of environmental changes on ventilation-tube insertion was smaller than on OM prevalence. The average number of ventilating-tube insertions decreased by 28.1% from 27 311 in 2017 to 2019 to 19 650 in 2020 to 2021. CONCLUSIONS: OM prevalence decreased by 45.0%, and the number of ventilating-tube insertions decreased by 28.1% in Korea during COVID-19.

Mucosa-associated Lymphoid Tissue Misdiagnosis as Glomus Tympanicum.

Middle ear tumors are diverse, but relatively uncommon. The most frequent tumor in the middle ear is glomus tumor, followed by others such as schwannoma and cholesteatoma. We experienced a case of Mucosa-associated lymphoid tissue hyperplasia as a middle ear tumor. The mass behind tympanic membrane appeared a hypervascular tumor, mimicking a glomus tumor, but the form of multiple separate masses in middle ear and mastoid cavity was the distinguishing feature that set it apart from a glomus tumor. Additionally, another characteristic was its tendency to easily shrink under pressure. This characteristic should be considered when encounter a hypervascular looking middle ear mass. Laryngoscope, 134:1894-1896, 2024.

Hydrophilic and lipophilic statin use and risk of hearing loss in hyperlipidemia using a Common Data Model: multicenter cohort study.

Hearing impairment, the third largest health burden worldwide, currently lacks definitive treatments or preventive drugs. This study compared the effects of hydrophilic and lipophilic statin on hearing loss using a common database model. This retrospective multicenter study was conducted in three hospitals in South Korea (Anam, Guro, Ansan). We enrolled patients with hyperlipidemia with an initial hearing loss diagnosis. Data were collected during January 1, 2022-December 31, 2021 using the Observational Health Data Science and Informatics open-source software and Common Data Model database. The primary outcome was the occurrence of first-time hearing loss following a hyperlipidemia diagnosis, as documented in the Common Data Model cohort database. The measures of interest were hearing loss risk between hydrophilic and lipophilic statin use. Variables were compared using propensity score matching, Cox proportional regression, and meta-analysis. Among 37,322 patients with hyperlipidemia, 13,751 (7669 men and 6082 women) and 23,631 (11,390 men and 12,241 women) were treated with hydrophilic and lipophilic statins, respectively. After propensity score matching, according to the Kaplan-Meier curve, hearing loss risk did not significantly differ among the hospitals. The hazard ratio (HR) of the male patients from Anam (0.29, [95% confidence interval (CI), 0.05-1.51]), Guro (HR, 0.56, [95% CI 0.18-1.71]), and Ansan (hazard ratio, 0.29, [95% CI 0.05-1.51]) hospitals were analyzed using Cox proportional regression. Overall effect size (HR, 0.40, [95% CI 0.18-0.91]) was estimated using meta-analysis, which indicated that hearing loss risk among hydrophilic statin users was less than that among lipophilic statin users and was statistically significant. Men in the hydrophilic statin group had a lower risk of hearing impairment than those in the lipophilic statin group.

Regenerative capacity of trophoblast stem cell-derived extracellular vesicles on mesenchymal stem cells.

BACKGROUND: Human mesenchymal stem cells (MSCs) are therapeutic for clinical applications because of their excellent immunomodulatory and multiple lineage differentiation abilities at tissue injury sites. However, insufficient number of cells and lack of regenerative properties during in vitro expansion still limit the clinical applicability of MSC therapies. Here, we demonstrated a preconditioning strategy with trophoblast stem cell-derived extracellular vesicles (TSC-EVs) to boost the proliferation and regenerative capacity of MSCs. METHODS: We employed cell proliferation analyses such as CCK8 and BrdU assays to determine the proliferation-promoting role of TSC-EVs on MSCs. Osteogenic effects of TSC-EVs on MSCs were assessed by alkaline phosphatase (ALP) activity, calcium assays, and calvarial bone defect animal models. For skin regenerative effects, skin wound mice model was exploited to analyze wound-healing rate in this study, as well as immunofluorescence and histological staining evaluates. We also performed the small RNA profiling and RNA-sequencing analyzes to understand the cellular mechanism of TSC-EVs on MSCs. RESULTS: TSC-EVs significantly promoted MSC proliferation under xeno-free conditions and facilitated the therapeutic effects of MSCs, including osteogenesis, anti-senescence, and wound healing. Transcriptomic analysis also provided evidence that specific microRNAs in TSC-EVs and differentially expressed genes (DEGs) in TSC-EV-treated MSCs showed the possibility of TSC-EVs triggering the regenerative abilities of MSCs with cytokine interaction. Hence, we found that NGF/Akt signaling mediated the regenerative effects of TSC-EVs on MSCs as a particular cellular signaling pathway. CONCLUSION: The results of this study demonstrated the functional properties of TSC-EVs on MSCs for MSC-based therapeutic applications, suggesting that TSC-EVs may serve as a potential preconditioning source for MSC therapy in the clinical field of regenerative medicine.

Osteogenic Efficacy of Human Trophoblasts-Derived Conditioned Medium on Mesenchymal Stem Cells.

Trophoblasts play an important role in the regulation of the development and function of the placenta. Our recent study demonstrated the skin regeneration capacity of trophoblast-derived extracellular vesicles (EV). Here, we aimed to determine the potential of trophoblast-derived conditioned medium (TB-CM) in enhancing the osteogenic differentiation of bone marrow mesenchymal stem cells (MSCs). We found that TB-CM promoted the osteogenic differentiation of MSCs in a dose-dependent manner. Furthermore, it inhibited adipogenesis of MSCs. We also found that the primary trophoblast-derived conditioned medium (PTB-CM) significantly enhanced the proliferation and osteogenic differentiation of human MSCs. Our study demonstrated the regulatory mechanisms underlying the TB-CM-induced osteogenesis in MSCs. An upregulation of genes associated with cytokines/chemokines was observed. The treatment of MSCs with TB-CM stimulated osteogenesis by activating several biological processes, such as mitogen-activated protein kinase (MAPK) and bone morphogenetic protein 2 (BMP2) signaling. This study demonstrated the proliferative and osteogenic efficacies of the trophoblast-derived secretomes, suggesting their potential for use in clinical interventions for bone regeneration and treatment.

Complications of Nasopharyngeal Swabs and Safe Procedures for COVID-19 Testing Based on Anatomical Knowledge.

Nasopharyngeal swabs have been widely to prevent the spread of coronavirus disease 2019 (COVID-19). Nasopharyngeal COVID-19 testing is a generally safe and well-tolerated procedure, but numerous complications have been reported in the media. Therefore, the present study aimed to review and document adverse events and suggest procedural references to minimize preventable but often underestimated risks. A total of 27 articles were selected for the review of 842 related documents in PubMed, Embase, and KoreaMed. The complications related to nasopharyngeal COVID-19 testing were reported to be rarely happened, ranging from 0.0012 to 0.026%. Frequently documented adverse events were retained swabs, epistaxis, and cerebrospinal fluid leakage, often associated with high-risk factors, including severe septal deviations, pre-existing skull base defects, and previous sinus or transsphenoidal pituitary surgery. Appropriate techniques based on sufficient anatomical knowledge are mandatory for clinicians to perform nasopharyngeal COVID-19 testing. The nasal floor can be predicted by the line between the nostril and external ear canal. For safe testing, the angle of swab insertion in the nasal passage should remain within 30° of the nasal floor. The swab was gently inserted along the nasal septum just above the nasal floor to the nasopharynx and remained on the nasopharynx for several seconds before removal. Forceful insertion should be attempted, and alternative examinations should be considered, especially in vulnerable patients. In conclusion, patients and clinicians should be aware of rare but possible complications and associated high-risk factors. The suggested procedural pearls enable more comfortable and safe nasopharyngeal COVID-19 testing for both clinicians and patients.

Different Transcutaneous Auricular Vagus Nerve Stimulation Parameters Modulate the Anti-Inflammatory Effects on Lipopolysaccharide-Induced Acute Inflammation in Mice.

Vagus nerve stimulation (VNS) is considered a potential method for anti-inflammation due to the involvement of the VN in the cholinergic anti-inflammatory pathway (CAP) formation of a connection between the central nervous system and peripheral immune cells that help relieve inflammation. However, whether a non-invasive transcutaneous auricular VNS (taVNS) modulates the inflammation levels via altering the parameter of taVNS is poorly understood. This study aimed to determine the differential inhibitory effects of taVNS on lipopolysaccharide (LPS)-induced systemic inflammation using electrical stimulation parameters such as pulse frequency and time. The taVNS-promoted CAP activity significantly recovered LPS-induced tissue injuries (lung, spleen, and intestine) and decreased inflammatory cytokine levels and tissue-infiltrated immune cells. Interestingly, the anti-inflammatory capacity of taVNS with 15 Hz was much higher than that of taVNS with 25 Hz. When a cytokine array was used to investigate the changes of inflammation and immune response-related cytokines/chemokines expression in taVNS with 15 Hz or 25 Hz treatment in LPS-induced endotoxemia in mice, most of the expression of cytokines/chemokines associated with pro-inflammation was severely decreased in taVNS with 15 Hz compared to 25 Hz. This study demonstrated that the taVNS parameter could differentially modulate the inflammation levels of animals, suggesting the importance of taVNS parameter selection for use in feasible interventions for acute inflammation treatment.

Comprehensive analysis of human chorionic membrane extracts regulating mesenchymal stem cells during osteogenesis.

OBJECTIVE: Human chorionic membrane extracts (CMEs) from placenta are known to be a natural biomaterial for bone regeneration, with their excellent osteogenic efficacy on osteoblasts. However, little is known about the regulatory mechanism involved. METHODS AND RESULTS: We have shown the in vitro and in vivo bone-forming ability of CME using human osteoblasts and bone defect animal models, suggesting that CME greatly enhances osteogenesis by providing an osteoconductive environment for the osteogenesis of osteoblasts. Proteomic analysis revealed that CME contained several osteogenesis-related stimulators such as osteopontin, osteomodulin, Thy-1, netrin 4, retinol-binding protein and DJ-1. Additionally, 23 growth factors/growth factor-related proteins were found in CME, which may trigger mitogen-activated protein kinase (MAPK) signalling as a specific cellular signalling pathway for osteogenic differentiation. Microarray analysis showed four interaction networks (chemokine, Wnt signalling, angiogenesis and ossification), indicating the possibility that CME can promote osteogenic differentiation through a non-canonical Wnt-mediated CXCL signalling-dependent pathway. CONCLUSIONS: The results of this study showed the function and mechanism of action of CME during the osteogenesis of osteoblasts and highlighted a novel strategy for the use of CME as a biocompatible therapeutic material for bone regeneration.

Change of gait after unilateral vestibular neuritis: a prospective longitudinal observation study.

Although symptoms of unilateral vestibular neuritis (uVN) resolve spontaneously within several weeks, recovery of gait function has unclearness in gait parameter changes and mediolateral stability improvements. In addition, prospective longitudinal studies on gait parameters after uVN are lacking. This study was conducted to reveal longitudinal change of gait function after acute uVN and to help the precise rehabilitation planning. Twenty three participants with uVN and 20 controls were included. 3D gait analyses were conducted three times after uVN onset at monthly intervals. From the gait analysis data, spatio-temporal parameters, inclination angle (IA) representing the relationship between center of mass (CoM) and center of pressure (CoP) in the frontal plane, and IA variability were obtained. Time effects on gait metrics were tested. Walking speed of participants with uVN improved significantly between the 1st and 3rd tests, but they were not significantly different to that of control, even in the 1st test. The step width of participants with uVN was significantly larger than that of control in the 1st test and improved significantly in the 2nd test. Variability of IA in affected side was significantly larger than that in controls in the 1st test and improved significantly in the 3rd test compared to the 1st test. Improvement of overall gait function and mediolateral stability during gait continued after acute stage of uVN (two months from onset in this study). Rehabilitation intervention should be continued after the acute stage of uVN to enhance appropriate adaptation in gait.

Exploratory fall risk and preventive intervention in acute vestibular neuritis.

OBJECTIVE: To analyze recovery from dizziness in patients with acute vestibular neuritis (AVN) after applying the "Dizziness & Fall Risk Assessment and Intervention (DFRAI)". METHODS: This prospective study involved patients with AVN who underwent a survey of dizziness and fall risk. The patients received medical treatment and customized vestibular rehabilitation, and vestibular function was evaluated at the initial attack and 3 months later. RESULTS: Forty-one patients underwent subjective questionnaire assessments, which showed significant improvement in visual analog scale-dizziness handicap inventory-fear of falling (VAS-DHI-FOF) results from the initial vertigo attack to 3 months later. In the sensory organization test (SOT), the initial composite score was 63 ± 13.1, which improved to 77.5 ± 4.9 3 months later. In caloric testing, the canal paresis (CP) score was 42.9 ± 35.2, which improved to 29.9 ± 23.5 3 months later. CONCLUSIONS: Subjective improvement in dizziness and objective recovery of vestibular function were confirmed. DFRAI is a comprehensive solution for dizziness, and appropriate application of the DFRAI is expected to have a positive effect on recovery from dizziness and fall prevention in patients with AVN.

Extracellular Vesicles (Secretomes) from Human Trophoblasts Promote the Regeneration of Skin Fibroblasts.

To date, placental trophoblasts have been of interest in the fields of obstetrics and gynecology, mainly due to their involvement in the formation of a connection between the mother and fetus that aids in placental development and fetal survival. However, the regenerative capacities of trophoblasts for application in regenerative medicine and tissue engineering are poorly understood. Here, we aim to determine the skin regeneration and anti-aging capacities of trophoblast-derived conditioned medium (TB-CM) and exosomes (TB-Exos) using human normal dermal fibroblasts (HNDFs). TB-CM and TB-Exos treatments significantly elevated the migration and proliferation potencies of HNDF cells in a dose- and time-dependent manner. When RNA sequencing (RNA-seq) was used to investigate the mechanism underlying TB-CM-induced cell migration on scratch-wounded HNDFs, the increased expression of genes associated with C-X-C motif ligand (CXCL) chemokines, toll-like receptors, and nuclear factor-kappa B (NF-κB) signaling was observed. Furthermore, treatment of intrinsically/extrinsically senescent HNDFs with TB-CM resulted in an enhanced rejuvenation of HNDFs via both protection and restoration processes. Gene expression of extracellular matrix components in the skin dermis significantly increased in TB-CM- and TB-Exos-treated HNDFs. These components are involved in the TB-CM and Exo-mediated regeneration and anti-aging of HNDFs. Thus, this study demonstrated the regenerative and anti-aging efficacies of trophoblast-derived secretomes, suggesting their potential for use in interventions for skin protection and treatment.

Osteogenic effects of exosomes derived from human chorion membrane extracts.

OBJECTIVE: Human chorion membrane extracts (CME) are known to exhibit osteogenic effects when used for treating human osteoblast-like cells (MG63 cells), but the active compound in CME remains unknown. The aim of this study was to identify the presence of exosomes in CME and to determine the osteogenic effect of CME exosomes on MG63 cells. METHODS: Exosomes were isolated from human placenta CME using the ExoQuick-TC solution and were characterized. The activity and deposition of alkaline phosphatase (ALP) on MG63 cells cultured with or without exosomes in osteogenic induction medium (OIM) were determined. Human amniotic membrane extracts (AME) were used as controls as they had not affected the osteogenic differentiation of MG63 cells in our previous study. RESULTS: Transmission electron microscopy (TEM) revealed that exosomes isolated from CME and AME (CME-Exo and AME-Exo, respectively) had a cup-shaped structure. NanoSight™ particle tracking analysis (NTA) confirmed that the size of these exosomes was 100-150 nm. In vitro osteogenic experiments demonstrated that the exosomes from CME, but not those from AME, presented increased alkaline phosphatase (ALP) activity and resulted in the mineralization of MG63 cells in a dose-dependent manner. CONCLUSION: Exosomes were identified in CME and AME from the human placenta. Further, the exosomes from CME were found to be capable of promoting osteogenic differentiation, suggesting that exosomes are a key component of CME that stimulate the osteogenesis of human osteoblast-like cells. CME exosomes can be developed as promising therapeutic candidates for bone regeneration.

Auditory brainstem response test results in normal hearing adolescents with subjective tinnitus.

OBJECTIVES: The objective of the study was to analyze the auditory brainstem response (ABR) test results of adolescents with normal hearing threshold who have subjective tinnitus in an effort to determine the probable site of origin of tinnitus. METHODS: Among the patients who visited the outpatient clinic of the Department of Otolaryngology at our tertiary hospital from January 2016 to December 2019, adolescents aged 13-18 years with the chief complaint of unilateral subjective tinnitus and pure tone audiometry (PTA) within 25 dB HL were enrolled and retrospectively reviewed. The ABR test parameters (amplitudes and latencies of waves I, III, and V and interpeak latencies [IPLs] of waves I-III, III-V, and I-V) were analyzed and compared between tinnitus ears and contralateral ears without tinnitus. Study participants were divided into the chronic tinnitus (tinnitus duration ≥6 months) and non-chronic tinnitus (tinnitus duration <6 months) groups, and the difference between the two groups was analyzed. RESULTS: Ten adolescents were included in the study, and their ABR test results were reviewed. IPL III-V was significantly prolonged in tinnitus ears compared to non-tinnitus ears (p = 0.035). Although other parameters were found to be statistically non-significant, there was preponderance in ABR wave I amplitude; it was smaller in tinnitus ears of chronic tinnitus adolescents than in those of non-chronic tinnitus adolescents (p = 0.114). CONCLUSION: The probable site of origin of tinnitus in adolescents with normal hearing might be in the upper brainstem of the auditory pathway. Further analysis of ABR test results in adolescents with tinnitus and normal hearing can help clarify the pathophysiology of tinnitus in adolescents.

Cannabidiol enhances cytotoxicity of anti-cancer drugs in human head and neck squamous cell carcinoma.

Cannabidiol (CBD) has anti-tumorigenic activity. However, the anti-cancer effect of CBD on head and neck squamous cell carcinoma (HNSCC) remains unclear. The cytotoxicity of CBD on HNSCC was analyzed using cell survival and colony-forming assays in vitro. RNA-seq was used for determining the mechanism underlying CBD-induced cell death. Xenograft mouse models were used to determine CBD's effects in vivo. CBD treatment significantly reduced migration/invasion and viability of HNSCC cells in a dose- and time-dependent manner. HNSCC mouse xenograft models revealed anti-tumor effects of CBD. Furthermore, combinational treatment with CBD enhanced the efficacy of chemotherapy drugs. Apoptosis and autophagy processes were involved in CBD-induced cytotoxicity of HNSCCs. RNA-seq identified decreased expression of genes associated with DNA repair, cell division, and cell proliferation, which were involved in CBD-mediated cytotoxicity toward HNSCCs. We identified CBD as a new potential anti-cancer compound for single or combination therapy of HNSCC.

Is postural dysfunction related to sarcopenia? A population-based study.

Postural dysfunction is one of the most common community health symptoms and frequent chief complaints in hospitals. Sarcopenia is a syndrome characterized by degenerative loss of skeletal muscle mass, muscle quality, and muscle strength, and is the main contributor to musculoskeletal impairment in the elderly. Previous studies reported that loss of muscle mass is associated with a loss of diverse functional abilities. Meanwhile, there have been limited studies concerning postural dysfunction among older adults with sarcopenia. Although sarcopenia is primarily a disease of the elderly, its development may be associated with conditions that are not exclusively seen in older persons. Also, recent studies recognize that sarcopenia may begin to develop earlier in life. The objective of this paper was to investigate the association between the prevalence of sarcopenia and postural dysfunction in a wide age range of adults using data from a nationally representative cohort study in Korea. Korean National Health & Nutrition Exhibition Survey V (KNHANES V, 2010-2012) data from the fifth cross-sectional survey of the South Korean population performed by the Korean Ministry of Health and Welfare were used. Appendicular skeletal muscle mass (ASM)/height (ht)2 was used to define sarcopenia, and the Modified Romberg test using a foam pad ("foam balance test") was performed to evaluate postural dysfunction. ASM/ht2 was lower in women and significantly decreased with age in men. Subjects with sarcopenia were significantly more likely to fail the foam balance test, regardless of sex and age. Regression analysis showed a significant relationship between sarcopenia and postural dysfunction (OR: 2.544, 95% CI: 1.683-3.846, p<0.001). Multivariate regression analysis revealed that sarcopenia (OR: 1.747, 95% CI: 1.120-2.720, p = 0.014) and age (OR: 1.131, 95% CI: 1.105-1.158, p<0.001) are independent risk factors for postural instability. In middle age subjects, the adjusted OR for sarcopenia was 3.344 (95% CI: 1.350-8.285) (p = 0.009). The prevalence of postural dysfunction is higher in sarcopenia patients, independent of sex and age.

Asian Sand Dust Particles Increased Pneumococcal Biofilm Formation in vitro and Colonization in Human Middle Ear Epithelial Cells and Rat Middle Ear Mucosa.

INTRODUCTION: Air pollutants such as Asian sand dust (ASD) and Streptococcus pneumoniae are risk factors for otitis media (OM). In this study, we evaluate the role of ASD in pneumococcal in vitro biofilm growth and colonization on human middle ear epithelium cells (HMEECs) and rat middle ear using the rat OM model. METHODS: S. pneumoniae D39 in vitro biofilm growth in the presence of ASD (50-300 µg/ml) was evaluated in metal ion-free BHI medium using CV-microplate assay, colony-forming unit (cfu) counts, resazurin staining, scanning electron microscopy (SEM), and confocal microscopy (CF). Biofilm gene expression analysis was performed using real-time RT-PCR. The effects of ASD or S. pneumoniae individually or on co-treatment on HMEECs were evaluated by detecting HMEEC viability, apoptosis, and reactive oxygen species (ROS) production. In vivo colonization of S. pneumoniae in the presence of ASD was evaluated using the rat OM model, and RNA-Seq was used to evaluate the alterations in gene expression in rat middle ear mucosa. RESULTS: S. pneumoniae biofilm growth was significantly (P < 0.05) elevated in the presence of ASD. SEM and CF analysis revealed thick and organized pneumococcal biofilms in the presence of ASD (300 µg/ml). However, in the absence of ASD, bacteria were unable to form organized biofilms, the cell size was smaller than normal, and long chain-like structures were formed. Biofilms grown in the presence of ASD showed elevated expression levels of genes involved in biofilm formation (luxS), competence (comA, comB, ciaR), and toxin production (lytA and ply). Prior exposure of HMEECs to ASD, followed by treatment for pneumococci, significantly (P < 0.05) decreased cell viability and increased apoptosis, and ROS production. In vivo experiment results showed significantly (P < 0.05) more than 65% increased bacteria colonization in rat middle ear mucosa in the presence of ASD. The apoptosis, cell death, DNA repair, inflammation and immune response were differentially regulated in three treatments; however, number of genes expressed in co-treatments was higher than single treatment. In co-treatment, antimicrobial protein/peptide-related genes (S100A family, Np4, DEFB family, and RATNP-3B) and OM-related genes (CYLD, SMAD, FBXO11, and CD14) were down regulated, and inflammatory cytokines and interleukins, such as IL1ß, and TNF-related gene expression were elevated. CONCLUSION: ASD presence increased the generation of pneumococcal biofilms and colonization.

Association Between Hearing Loss and Postural Instability in Older Korean Adults.

Importance: Hearing loss is one of the most frequently occurring sensory disabilities worldwide. The association between hearing loss and postural instability in an older population remains to be studied. Objective: To determine whether the odds of postural instability increase with the degree of hearing loss and to suggest criteria for hearing rehabilitation for postural instability. Design, Setting, and Participants: This cross-sectional population-based study of 3864 participants 40 years and older with hearing loss used data from 2010 through 2012 in the fifth edition of the Korea National Health and Nutrition Examination Survey, a nationwide survey of South Korea. Pure tone audiometry was performed on both the left and right sides and each hearing grade of each side was classified into 1 of 3 subcategories: normal hearing, mild hearing loss, or moderate hearing loss (moderate hearing loss or worse). Postural instability was defined as the failure to remain standing on a foam pad surface with feet 10 cm apart with arms folded and hands cupping the elbows and eyes closed. A binomial logistic regression model was used to assess the association between hearing loss and postural instability. Data were analyzed from August 18, 2019, to September 2, 2019. Exposures: Age-related hearing loss defined as a threshold of 26 dB or more. Main Outcomes and Measures: The degree of hearing loss and postural instability. Results: Of the 3864 participants included in the study, the mean (SD) age was 57.8 (11.3) years and 2135 (55.2%) were women. Female sex was associated with higher odds of postural instability compared with male sex (odds ratio [OR], 1.65; 95% CI, 1.12-2.42, adjusted for age and hearing status), and the odds of postural instability increased with every 1 year increase in age (OR, 1.13; 95% CI, 1.10-1.16, adjusted for sex and hearing status). Unilateral or bilateral mild hearing loss was not associated with an increase in the odds of postural instability, but moderate hearing loss present on at least 1 side was associated with an increase in the odds of postural instability: unilateral moderate hearing loss group (OR, 2.71; 95% CI, 1.12-6.10, adjusted for age and sex), one mild and the other moderate hearing loss group (OR, 2.18; 95% CI, 1.16-4.09, adjusted for age and sex), and bilateral moderate hearing loss group (OR, 2.34; 95% CI, 1.27-4.33, adjusted for age and sex). Conclusions and Relevance: Aging, female sex, and having hearing loss were associated with postural instability in this analysis. Moderate or worse hearing loss present on at least 1 side was associated with increased odds of postural instability. Future research in this area is warranted to identify more precise interrelationships and preventive measures.

The change of prevalence and recurrence of acute otitis media in Korea.

OBJECTIVES: Acute otitis media (AOM) is the most common infectious disease in infants and children. However, there have been few studies on the recent prevalence and trends of pediatric AOM in Korea. This study aimed to evaluate the prevalence and trends of pediatric AOM in Korea. METHODS: The data for patients with AOM in 2012, 2015, and 2017 were extracted from the Health Insurance Review and Assessment Service's Big Database. The prevalence rate, recurrence rate, and data on gender, region, month, and medical facilities of AOM were evaluated. RESULTS: The prevalence rate (per 1000 persons) decreased from 152.7 in 2012 to 137.4 in 2017. The recurrence rate declined from 34.0% in 2012 to 28.2% in 2015. In 2015, the recurrence rate of 0-2 years group decreased significantly. In 2017, the prevalence of AOM of 3-6 years group decreased the most. The prevalence is higher in urban areas and recurrence rate is higher in rural areas. But those are no significant difference. AOM is more common in male, mainly in winter and spring. CONCLUSIONS AND SIGNIFICANCE: The prevalence and recurrence rate of pediatric AOM in Korea are gradually decreasing. The decrease of prevalence resulted from declination in AOM recurrence of 0-2 years group in 2015 and AOM occurrence of 3-6 years group in 2017.

Urban Particles Elevated Streptococcus pneumoniae Biofilms, Colonization of the Human Middle Ear Epithelial Cells, Mouse Nasopharynx and Transit to the Middle Ear and Lungs.

Air-pollutants containing toxic particulate matters (PM) deposit in the respiratory tract and increases microbial infections. However, the mechanism by which this occurs is not well understood. This study evaluated the effect of urban particles (UP) on Streptococcus pneumoniae (pneumococcus) in vitro biofilm formation, colonization of human middle ear epithelium cells (HMEECs) as well as mouse nasal cavity and its transition to the middle ear and lungs. The in vitro biofilms and planktonic growth of S. pneumoniae were evaluated in metal ion free medium in the presence of UP. Biofilms were quantified by crystal violet (CV) microplate assay, colony forming unit (cfu) counts and resazurin staining. Biofilm structures were analyzed using a scanning electron microscope (SEM) and confocal microscopy (CM). Gene expressions of biofilms were evaluated using real time RT-PCR. Effects of UP exposure on S. pneumoniae colonization to HMEECs were evaluated using fluorescent in-situ hybridization (FISH), cell viability was detected using the Ezcyto kit, apoptosis in HMEECs were evaluated using Annexin-V/PI based cytometry analysis and reactive oxygen species (ROS) production were evaluated using the Oxiselect kit. Alteration of HMEECs gene expressions on UP exposure or pneumococci colonization was evaluated using microarray. In vivo colonization of pneumococci in the presence of UP and transition to middle ear and lungs were evaluated using an intranasal mice colonization model. The UP exposure significantly increased (*p < 0.05) pneumococcal in vitro biofilms and planktonic growth. In the presence of UP, pneumococci formed organized biofilms with a matrix, while in absence of UP bacteria were unable to form biofilms. The luxS, ply, lytA, comA, comB and ciaR genes involved in bacterial pathogenesis, biofilm formation and quorum sensing were up-regulated in pneumococci biofilms grown in the presence of UP. The HMEECs viability was significantly decreased (p < 0.05) and bacteria colonization was significantly elevated (p < 0.05) in co-treatment (UP + S. pneumoniae) when compared to single treatment. Similarly, increased apoptosis and ROS production were detected in HMEECs treated with UP + pneumococci. The microarray analysis of HMEECs revealed that the genes involve in apoptosis and cell death, inflammation, and immune response, were up-regulated in co-treatment and were unchanged or expressed in less fold in single treatments of UP or S. pneumoniae. The in vivo study showed an increased pneumococcal colonization of the nasopharynx in the presence of UP and a higher transition of bacteria to the middle ear and lungs in the presence of UP. The UP exposure elevated S. pneumoniae in vitro biofilm and colonization of HMEECs, and in vivo mouse nasopharyngeal colonization, and increased dissemination to mouse middle ear and lungs.