C-Phycocyanin Attenuates Noise-Induced Cochlear Synaptopathy via the Inhibition of Oxidative Stress and Intercellular Adhesion Molecule-1 in the Cochlea.

The synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) are the most vulnerable structures in the noise-exposed cochlea. Cochlear synaptopathy results from the disruption of these synapses following noise exposure and is considered the main cause of poor speech understanding in noisy environments, even when audiogram results are normal. Cochlear synaptopathy leads to the degeneration of SGNs if damaged IHC-SGN synapses are not promptly recovered. Oxidative stress plays a central role in the pathogenesis of cochlear synaptopathy. C-Phycocyanin (C-PC) has antioxidant and anti-inflammatory activities and is widely utilized in the food and drug industry. However, the effect of the C-PC on noise-induced cochlear damage is unknown. We first investigated the therapeutic effect of C-PC on noise-induced cochlear synaptopathy. In vitro experiments revealed that C-PC reduced the H2O2-induced generation of reactive oxygen species in HEI-OC1 auditory cells. H2O2-induced cytotoxicity in HEI-OC1 cells was reduced with C-PC treatment. After white noise exposure for 3 h at a sound pressure of 118 dB, the guinea pigs intratympanically administered 5 µg/mL C-PC exhibited greater wave I amplitudes in the auditory brainstem response, more IHC synaptic ribbons and more IHC-SGN synapses according to microscopic analysis than the saline-treated guinea pigs. Furthermore, the group treated with C-PC had less intense 4-hydroxynonenal and intercellular adhesion molecule-1 staining in the cochlea compared with the saline group. Our results suggest that C-PC improves cochlear synaptopathy by inhibiting noise-induced oxidative stress and the inflammatory response in the cochlea.

Solitary Bone Plasmacytoma of the Skull Base With an Unusual Presentation.

Solitary bone plasmacytoma (SBP) is a rare hematological malignancy that usually occurs in the spine and rarely in the skull. It rarely presents in the skull base, but presenting symptoms are associated with cranial nerve involvement depending on the site of the disease. We present the case of a 61-year-old man with an unusual presentation of hoarseness secondary to vocal fold palsy. Imaging showed a large bony lesion in the temporo-occipital region with involvement of the jugular foramen. Further detailed diagnostic procedures confirmed SBP of the skull base. Radiotherapy was given with an uneventful recovery of vocal fold function. Skull base plasmacytoma can be considered as a differential diagnosis of causes of unilateral vocal fold palsy. Early therapeutic management may improve vocal fold function.

Increased risk of psychiatric disorder in patients with hearing loss: a nationwide population-based cohort study.

BACKGROUND: Hearing loss has been shown to be a risk factor for psychiatric disorders. In addition, long-term hearing loss is associated with increased hospitalization and mortality rates; however, the increased risk and duration of effect of hearing loss in combination with other chronic diseases on each psychiatric disorder are still not clearly defined. The purpose of this article is to clarify the risk of hearing loss for each disorder over time. METHODS: This was a retrospective cohort study, and a national health insurance research database in Taiwan was utilized. All (n = 1,949,101) Taiwanese residents who had a medical visit between 2000 and 2015 were included. Patients with hearing loss and a comparative retrospective cohort were analyzed. Every subject was tracked individually from their index date to identify the subjects who later received a diagnosis of a psychiatric disorder. The Kaplan‒Meier method was used to analyze the cumulative incidence of psychiatric disorders. Cox regression analysis was performed to identify the risk of psychiatric disorders. RESULTS: A total of 13,341 (15.42%) and 31,250 (9.03%) patients with and without hearing loss, respectively, were diagnosed with psychiatric disorders (P < 0.001). Multivariate analysis indicated that hearing loss significantly elevated the risk of psychiatric disorders (adjusted HR = 2.587, 95% CI 1.723-3.346, p < 0.001). CONCLUSION: Our findings indicate that patients with hearing loss are more likely to develop psychiatric disorders. Furthermore, the various psychiatric disorders are more likely to occur at different times. Our findings have important clinical implications, including a need for clinicians to implement early intervention for hearing loss and to pay close attention to patients' psychological status. Trial registration TSGHIRB No. E202216036.

GRAIL gene knockout mice protect against aging-related and noise-induced hearing loss.

BACKGROUND: Hearing loss is a global health issue and its etiopathologies involve complex molecular pathways. The ubiquitin-proteasome system has been reported to be associated with cochlear development and hearing loss. The gene related to anergy in lymphocytes ( GRAIL ), as an E3 ubiquitin ligase, has not, as yet, been examined in aging-related and noise-induced hearing loss mice models. METHODS: This study used wild-type (WT) and GRAIL knockout (KO) mice to examine cochlear hair cells and synaptic ribbons using immunofluorescence staining. The hearing in WT and KO mice was detected using auditory brainstem response. Gene expression patterns were compared using RNA-sequencing to identify potential targets during the pathogenesis of noise-induced hearing loss in WT and KO mice. RESULTS: At the 12-month follow-up, GRAIL KO mice had significantly less elevation in threshold level and immunofluorescence staining showed less loss of outer hair cells and synaptic ribbons in the hook region compared with GRAIL WT mice. At days 1, 14, and 28 after noise exposure, GRAIL KO mice had significantly less elevation in threshold level than WT mice. After noise exposure, GRAIL KO mice showed less loss of outer hair cells in the cochlear hook and basal regions compared with WT mice. Moreover, immunofluorescence staining showed less loss of synaptic ribbons in the hook regions of GRAIL KO mice than of WT mice. RNA-seq analysis results showed significant differences in C-C motif chemokine ligand 19 ( CCL19 ), C-C motif chemokine ligand 21 ( CCL21 ), interleukin 25 ( IL25 ), glutathione peroxidase 6 ( GPX6 ), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 1 ( NOX1 ) genes after noise exposure. CONCLUSION: The present data demonstrated that GRAIL deficiency protects against aging-related and noise-induced hearing loss. The mechanism involved needs to be further clarified from the potential association with synaptic modulation, inflammation, and oxidative stress.

The association between hormone therapy and the risk of lung cancer in postmenopausal women: a 16-year nationwide population-based study.

OBJECTIVE: Although an association between hormone therapy (HT) and the risk of developing lung cancer has been reported, the results on the topic are inconsistent. Our study objective was to investigate whether postmenopausal women who undergo HT exhibit a risk of developing lung cancer. METHODS: In this matched cohort study, we obtained the data of 38,104 postmenopausal women older than 45 years who were treated using HT between 2000 and 2015 from Taiwan's National Health Insurance Research Database, and 152,416 matched participants who were not treated using HT were enrolled as controls at a 1:4 ratio. RESULTS: We used a Cox proportional hazards regression model to identify the risk of developing lung cancer during 16 years of follow-up, and the results indicate no significant difference in the proportion of postmenopausal women treated using HT ( P = 0.129) who developed lung cancer and that of those not treated using HT (0.866% [330 of 38,104] vs 0.950% [1,449 of 152,416]). After adjustment for age and other variables, the adjusted hazard ratio was 0.886 (95% CI, 0.666-1.305, P = 0.433), indicating no association between HT and lung cancer development in postmenopausal women. In a subgroup analysis, the risk of lung cancer was significantly lower in the women who were treated using HT when the HT cumulative dosage was ≥401 mg or when the therapy duration was ≥5 years compared with in those not treated using HT; the adjusted hazard ratios were 0.633 (95% CI, 0.475-0.930; P < 0.001) and 0.532 (95% CI, 0.330-0.934; P < 0.001), respectively, after adjustment. CONCLUSIONS: Our results indicate that HT is not associated with the risk of lung cancer development in postmenopausal women; furthermore, a higher cumulative dosage and the long-term effects of HT reduce the risk of developing lung cancer.

Inflammatory Pseudotumour of Temporal Bone in a Multiple-Comorbidity Patient.

Inflammatory pseudotumour (IPT) of the temporal bone is relatively rare in the head and neck, but it is important for clinicians to be aware of this emerging entity. A 39-year man presented with a protruding reddish mass over the left external ear. High-resolution Computed Tomography and Magnetic Resonance Imaging of temporal bone showed soft tissue collection in the left external ear, middle ear, and mastoid cavity with bony erosion. The patient first received modified radical mastoidectomy. Several surgeries were required for recurrences with eventual intracranial invasion within 2 years. The pathology showed chronic inflammation without malignancy, autoimmune or infectious pathologies. Based on the clinical manifestations, IPT was diagnosed. Finally, radiation therapy (RT) with 30 Gy was given. There was no recurrence following the RT course. Early recognition of IPT presenting as a recurrent and locally aggressive inflammatory lesion in the temporal bone is necessary to achieve favorable outcomes. Key Words: Inflammatory pseudotumour, Temporal bone, Radiation therapy.

The Association Between Dextromethorphan Use and the Risk of Dementia.

Dementia is one of neurodegenerative disease without preventive medicine currently. Dextromethorphan (DXM) has been reported to reduce neuronal damage and neurodegeneration in animal and human models. The effect of DXM on the dementia has not been fully examined. We examined the medical records over 40 years old in Taiwan's National Health Insurance Research Database between 2000 and 2015 to establish matched cohorts. We used a Cox regression hazard model to identify risk factors of dementia during 16 years of follow-up, and the results indicate that a significantly lower percentage of subjects with DXM use (P < .001) developed dementia compared with those without DXM use (11.38%, 4541/39 895 vs 18.66%, 29 785/159 580). After adjustment for age and other variables [adjusted hazard ratio: .567 (95% confidence interval: .413-.678, P < .001)], this study also demonstrated that DXM use appeared to reduce the risk of developing dementia. DXM use may potentially provide a protective effect against dementia.

Gastrointestinal Endoscopy Performed by Gastroenterologists: Opportunistic Screening Strategy for Newly Diagnosed Head and Neck Cancers.

Aim: Approximately 66% of head and neck cancers are diagnosed at an advanced stage. This prospective study aimed to detect newly diagnosed head and neck cancers using regular upper gastrointestinal (UGI) endoscopy with oral-pharynx-larynx examination. Methods: A total of 2,849 patients underwent UGI endoscopy with an additional oral-pharynx-larynx examination. Patients aged < 20 years, those who were pregnant, had a history of head and neck cancers, were undergoing emergency endoscopy, and had a poor laryngopharyngeal view were excluded. The symptoms, incidence, location, pathology, and stage of malignant neoplasms were investigated. Results: A total of 2,720 patients were enrolled. Endoscopically observable 23 abnormal findings (0.85%) included 18 (0.66%) benign lesions and 5 (0.18%) newly diagnosed malignant neoplasms. Notably, 4 (80%) of 5 patients with malignant neoplasms were diagnosed at an early stage (Stage 0, I, and II). Conclusions: UGI endoscopy with oral-pharynx-larynx examination can achieve opportunistic head neck cancer screening and is recommended for every patient in endoscopy units.

Solitary neurofibroma in the external auditory canal.

Significance Statement: Neurofibromas, derived from perineural cells, are usually benign in the nervous system. Although neurofibromas are common in the head and neck, they rarely affect the external auditory canal (EAC), and few cases have been reported. We describe a case of a solitary EAC neurofibroma with otoscopy, radiological imaging, a surgical approach, and an uneventful outcome.

Bilateral sudden sensorineural hearing loss in patient with Behçet disease.

Bacckground: Approximately 80% to 85% of sudden sensorineural hearing loss (SSNHL) is idiopathic, but immune-mediated mechanisms are thought to be involved. Behçet disease is an autoinflammatory vasculitis that may involve vessels of the inner ear. It can cause sensorineural hearing loss (SNHL) and an increased risk of SSNHL. Study Sample: We report a 21-year-old man who was diagnosed with Behçet disease in childhood and presented to our clinic with a 10-day history of abrupt hearing deterioration in both ears. Pure-tone audiometry showed severe to profound bilateral SNHL. Results: Oral prednisolone was prescribed for 3 weeks. Concurrent intratympanic steroid injections (ITSIs) were administered in each ear every 2 days for 5 days. A total of 15 daily sessions of hyperbaric oxygen therapy (HBOT) were completed. Acupuncture was performed every 2 days for 1 month. After these combined therapies, the patient's hearing threshold by 20 dB and his speech recognition threshold were improved. Conclusions: Some patients with SSNHL recover no hearing improvement after routine treatment, and alternative treatments including ITSI, HBOT, and acupuncture can be considered as optional. We used an aggressive multimodal approach to treat severe bilateral SSNHL in patient with Behçet disease.

Ultrasound Microbubble-Facilitated Inner Ear Delivery of Gold Nanoparticles Involves Transient Disruption of the Tight Junction Barrier in the Round Window Membrane.

The application of ultrasound microbubbles (USMBs) enhances the permeability of the round window membrane (RWM) and improves drug delivery to the inner ear. In this study, we investigated the efficiency of USMB-aided delivery of chitosan-coated gold nanoparticles (CS-AuNPs) and the mechanism of USMB-mediated enhancement of RMW permeability. We exposed mouse inner ears to USMBs at an intensity of 2 W/cm2 and then filled the tympanic bulla with CS-AuNPs or fluorescein isothiocyanate-decorated CS-AuNPs (FITC-CS-AuNPs). The membrane uptake of FITC-CS-AuNPs and their depth of permeation into the three-layer structure of the RWM, with or without prior USMB treatment, were visualized by z-stack confocal laser scanning microscopy. Ultrastructural changes in the RWM due to USMB-mediated cavitation appeared as sunburn-like peeling and various degrees of depression in the RWM surface, with pore-like openings forming in the outer epithelium. This disruption of the outer epithelium was paralleled by a transient reduction in tight junction (TJ)-associated protein levels in the RWM and an enhanced delivery of FITC-CS-AuNPs into the RWM. Without prior USMB exposure, the treatment with CS-AuNPs also caused a noticeable reduction in TJ proteins of the RWM. Our findings indicated that the combined treatment with USMBs and CS-AuNPs represents a promising and efficient drug and gene delivery vehicle for a trans-RWM approach for inner ear therapy. The outer epithelial layer of the RWM plays a decisive role in controlling the transmembrane transport of substances such as CS-AuNPs following the administration of USMBs. Most importantly, the enhanced permeation of AuNPs involved the transient disruption of the TJ-created paracellular barrier in the outer epithelium of the RWM.