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Ono M, Ito T. Hearing loss-related altered neuronal activity in the inferior colliculus. Hear Res 2024; 449:109033. [PMID: 38797036 DOI: 10.1016/j.heares.2024.109033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 05/01/2024] [Accepted: 05/13/2024] [Indexed: 05/29/2024]
Abstract
Hearing loss is well known to cause plastic changes in the central auditory system and pathological changes such as tinnitus and hyperacusis. Impairment of inner ear functions is the main cause of hearing loss. In aged individuals, not only inner ear dysfunction but also senescence of the central nervous system is the cause of malfunction of the auditory system. In most cases of hearing loss, the activity of the auditory nerve is reduced, but that of the successive auditory centers is increased in a compensatory way. It has been reported that activity changes occur in the inferior colliculus (IC), a critical nexus of the auditory pathway. The IC integrates the inputs from the brainstem and drives the higher auditory centers. Since abnormal activity in the IC is likely to affect auditory perception, it is crucial to elucidate the neuronal mechanism to induce the activity changes of IC neurons with hearing loss. This review outlines recent findings on hearing-loss-induced plastic changes in the IC and brainstem auditory neuronal circuits and discusses what neuronal mechanisms underlie hearing-loss-induced changes in the activity of IC neurons. Considering the different causes of hearing loss, we discuss age-related hearing loss separately from other forms of hearing loss (non-age-related hearing loss). In general, the main plastic change of IC neurons caused by both age-related and non-age-related hearing loss is increased central gain. However, plastic changes in the IC caused by age-related hearing loss seem to be more complex than those caused by non-age-related hearing loss.
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Affiliation(s)
- Munenori Ono
- Department of Physiology, School of Medicine, Kanazawa Medical University, Uchinada, Ishikawa 920-0293, Japan.
| | - Tetsufumi Ito
- Systems Function and Morphology, University of Toyama, Toyama 930-0194, Japan.
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Orikpete OF, Dennis NM, Kikanme KN, Ewim DRE. Advancing noise management in aviation: Strategic approaches for preventing noise-induced hearing loss. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 363:121413. [PMID: 38850921 DOI: 10.1016/j.jenvman.2024.121413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 06/10/2024]
Abstract
As urbanization and population growth escalate, the challenge of noise pollution intensifies, particularly within the aviation industry. This review examines current insights into noise-induced hearing loss (NIHL) in aviation, highlighting the risks to pilots, cabin crew, aircraft maintenance engineers, and ground staff from continuous exposure to high-level noise. It evaluates existing noise management and hearing conservation strategies, identifying key obstacles and exploring new technological solutions. While progress in developing protective devices and noise control technologies is evident, gaps in their widespread implementation persist. The study underscores the need for an integrated strategy combining regulatory compliance, technological advances, and targeted educational efforts. It advocates for global collaboration and policy development to safeguard the auditory health of aviation workers and proposes a strategic framework to enhance hearing conservation practices within the unique challenges of the aviation sector.
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Affiliation(s)
- Ochuko Felix Orikpete
- Centre for Occupational Health, Safety and Environment (COHSE), University of Port Harcourt, Choba, Rivers State, Nigeria
| | - Nicole M Dennis
- Department of Environmental and Global Health, University of Florida, USA
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Zhi W, Li Y, Wang Y, Zou Y, Wang H, Xu X, Ma L, Ren Y, Qiu Y, Hu X, Wang L. Effects of 90 dB pure tone exposure on auditory and cardio-cerebral system functions in macaque monkeys. ENVIRONMENTAL RESEARCH 2024; 249:118236. [PMID: 38266893 DOI: 10.1016/j.envres.2024.118236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/13/2024] [Accepted: 01/16/2024] [Indexed: 01/26/2024]
Abstract
Excessive noise exposure presents significant health risks to humans, affecting not just the auditory system but also the cardiovascular and central nervous systems. This study focused on three male macaque monkeys as subjects. 90 dB sound pressure level (SPL) pure tone exposure (frequency: 500Hz, repetition rate: 40Hz, 1 min per day, continuously exposed for 5 days) was administered. Assessments were performed before exposure, during exposure, immediately after exposure, and at 7-, 14-, and 28-days post-exposure, employing auditory brainstem response (ABR) tests, electrocardiograms (ECG), and electroencephalograms (EEG). The study found that the average threshold for the Ⅴ wave in the right ear increased by around 30 dB SPL right after exposure (P < 0.01) compared to pre-exposure. This elevation returned to normal within 7 days. The ECG results indicated that one of the macaque monkeys exhibited an RS-type QRS wave, and inverted T waves from immediately after exposure to 14 days, which normalized at 28 days. The other two monkeys showed no significant changes in their ECG parameters. Changes in EEG parameters demonstrated that main brain regions exhibited significant activation at 40Hz during noise exposure. After noise exposure, the power spectral density (PSD) in main brain regions, particularly those represented by the temporal lobe, exhibited a decreasing trend across all frequency bands, with no clear recovery over time. In summary, exposure to 90 dB SPL noise results in impaired auditory systems, aberrant brain functionality, and abnormal electrocardiographic indicators, albeit with individual variations. It has implications for establishing noise protection standards, although the precise mechanisms require further exploration by integrating pathological and behavioral indicators.
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Affiliation(s)
- Weijia Zhi
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Ying Li
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Yuchen Wang
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Yong Zou
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Haoyu Wang
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Xinping Xu
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Lizhen Ma
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Yanling Ren
- Animal Center of the Academy of Military Medical Sciences, Beijing, China.
| | - Yefeng Qiu
- Animal Center of the Academy of Military Medical Sciences, Beijing, China.
| | - Xiangjun Hu
- Beijing Institute of Radiation Medicine, Beijing, China.
| | - Lifeng Wang
- Beijing Institute of Radiation Medicine, Beijing, China.
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C Ong KM, Chiong CM, Reyes-Quintos MRT, Urgel RGVM, Estrella EP, Sison OT, Baja ES. Association between occupational noise exposure level and pure-tone audiometry abnormalities among Metropolitan Manila Development Authority employees: A cross-sectional study. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2024; 21:342-352. [PMID: 38489754 DOI: 10.1080/15459624.2024.2315164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
Traffic enforcers are exposed to various occupational health and safety hazards, including noise pollution, which may lead to occupational hearing loss. This cross-sectional study aimed to estimate the prevalence of hearing loss and to assess the relationship between occupational noise exposure level (ONEL) and abnormalities in air conduction thresholds among Metropolitan Manila Development Authority (MMDA) employees along Epifanio delos Santos Avenue, Philippines. Eight-hour ONELs were measured among 108 participants working with greater than 5 years of service. Participants had hearing evaluations using pure tone audiometry (PTA) to calculate the prevalence of hearing loss. Generalized linear models with a Poisson distribution were fitted to estimate the association between ONEL and audiologic abnormalities, controlling for confounding factors. Approximately 16% of employees had hearing loss. The prevalence of hearing loss was higher with ONEL exposures greater than 85 A-weighted decibels (dBA), with traffic enforcers exposed to higher ONELs than office workers. ONELs greater than 85 dBA were related to audiologic abnormalities at different frequencies in PTA. The prevalence of audiologic abnormalities at 4000 Hz and 6000 Hz was 48% higher (adjusted prevalence ratio [aPR], 1.48; 95% CI, 1.12-1.96) and 25% higher (aPR, 1.25; 95% CI, 1.00-1.55), respectively, among participants with ONELs greater than 85 dBA than with ONELs less than or equal to 85 dBA. Participants exposed to ONELs greater than 85 dBA, more likely traffic enforcers, may have increased risk of audiologic abnormalities. Regular ONEL monitoring is warranted for occupational risk assessment of traffic enforcers. A hearing conservation program may need to be considered for this population. Additional studies are needed to determine trends in hearing deterioration among traffic enforcers.
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Affiliation(s)
- Kimberly Mae C Ong
- National Institutes of Health, Philippine National Ear Institute, University of the Philippines, Manila, Philippines
- University of the Philippines-Philippine General Hospital, Manila, Philippines
| | - Charlotte M Chiong
- National Institutes of Health, Philippine National Ear Institute, University of the Philippines, Manila, Philippines
- University of the Philippines-Philippine General Hospital, Manila, Philippines
- College of Medicine, Department of Otolaryngology-Head and Neck Surgery, University of the Philippines, Manila, Philippines
| | - Maria Rina T Reyes-Quintos
- National Institutes of Health, Philippine National Ear Institute, University of the Philippines, Manila, Philippines
- University of the Philippines-Philippine General Hospital, Manila, Philippines
- College of Medicine, Department of Otolaryngology-Head and Neck Surgery, University of the Philippines, Manila, Philippines
| | | | - Emmanuel P Estrella
- University of the Philippines-Philippine General Hospital, Manila, Philippines
- National Institutes of Health, Institute of Clinical Epidemiology, University of the Philippines, Manila, Philippines
- College of Medicine, Department of Clinical Epidemiology, University of the Philippines, Manila, Philippines
| | - Olivia T Sison
- National Institutes of Health, Institute of Clinical Epidemiology, University of the Philippines, Manila, Philippines
- College of Medicine, Department of Clinical Epidemiology, University of the Philippines, Manila, Philippines
| | - Emmanuel S Baja
- National Institutes of Health, Institute of Clinical Epidemiology, University of the Philippines, Manila, Philippines
- College of Medicine, Department of Clinical Epidemiology, University of the Philippines, Manila, Philippines
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Tank ND, Rupani MP, Shah IA, Dhatrak SV. Prevalence and predictors of high-frequency hearing loss among mine workers in Gujarat, western India: a cross-sectional study on the need to implement a comprehensive hearing conservation program. Int Arch Occup Environ Health 2024; 97:365-375. [PMID: 38421415 DOI: 10.1007/s00420-024-02050-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 01/22/2024] [Indexed: 03/02/2024]
Abstract
BACKGROUND High-frequency hearing loss (HFHL) stands as a prevalent occupational morbidity globally, with numerous associated risk factors, some of which are modifiable. In the context of a comprehensive hearing conservation program, the initial steps involve early screening and identification of workers with these modifiable risk factors, aiming to reduce the prevalence of hearing loss. Our objective was to estimate the prevalence of HFHL and determine its predictors among mine workers. METHODS We conducted a cross-sectional study among 226 mine workers in ten open-cast mines in Gujarat state, the western part of India, in November 2020. We collected data on socio-demography, addiction, occupation history and comorbidities, along with anthropometric, blood pressure, and blood sugar measurements. Audiometric evaluations using a portable diagnostic audiometer were employed to assess HFHL, defined as a hearing threshold exceeding 25 decibels (dB) at high frequencies (3000, 4000, 6000, and 8000 Hz). A generalized linear model (GLM) with a binomial family was performed to determine the predictors significantly predicting HFHL after adjusting for confounding variables. RESULTS The prevalence of HFHL was 35% (95% CI: 29-42%) in our study setting. Office workers demonstrated a prevalence of 19%, whereas other job categories displayed a higher prevalence of 42%, resulting in a significant prevalence difference of 23% and a prevalence ratio of 2.2. The GLM analysis revealed that variables, such as noise exposure during work [adjusted prevalence ratio (aPR) 2.3 (95% CI: 1.2-4.7, p = 0.018)] and noise exposure duration [aPR 1.1 (95% CI: 1.0-1.1, p = 0.042)], were significant predictors of HFHL. CONCLUSIONS In our study setting, mine workers exhibited a high prevalence of HFHL, with exposure to workplace noise and duration being modifiable predictors. Because HFHL advances slowly and is generally undetected by the individual, we recommend periodic testing using audiometry to identify it among mine workers and, if possible, shifting them from mining activities to office. Furthermore, we advocate for the implementation of a comprehensive hearing conservation program to the extent possible.
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Affiliation(s)
- Nitishkumar D Tank
- Poison Information Center, Division of Health Sciences, ICMR - National Institute of Occupational Health (NIOH), Meghani Nagar, Near Raksha Shakti Circle, Ahmedabad, Gujarat, 380016, India
| | - Mihir P Rupani
- Clinical Epidemiology, Division of Health Sciences, ICMR - National Institute of Occupational Health (NIOH), Meghani Nagar, Ahmedabad, Gujarat, 380016, India
| | - Immad A Shah
- Clinical Epidemiology, Division of Health Sciences, ICMR - National Institute of Occupational Health (NIOH), Meghani Nagar, Ahmedabad, Gujarat, 380016, India
| | - Sarang V Dhatrak
- Poison Information Center, Division of Health Sciences, ICMR - National Institute of Occupational Health (NIOH), Meghani Nagar, Near Raksha Shakti Circle, Ahmedabad, Gujarat, 380016, India.
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Tran Y, Tang D, Lo C, Macken O, Newall J, Bierbaum M, Gopinath B. Establishing multifactorial risk factors for adult-onset hearing loss: A systematic review with topic modelling and synthesis of epidemiological evidence. Prev Med 2024; 180:107882. [PMID: 38296002 DOI: 10.1016/j.ypmed.2024.107882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/24/2024] [Accepted: 01/27/2024] [Indexed: 02/25/2024]
Abstract
BACKGROUND This systematic review explores the multifaceted nature of risk factors contributing to adult-onset HL. The objective was to synthesise the most recent epidemiological evidence to generate pooled proportional incidences for the identified risk factors. METHODS We conducted an extensive search of electronic databases (MEDLINE, EMBASE, and psychINFO) for studies providing epidemiological evidence of risk factors associated with hearing loss. Topic modelling using Latent Dirichlet Allocation (LDA) was first conducted to determine how many risk factor themes were available from the papers. Data were analysed by calculating the pooled proportional incidence using a meta-analysis of proportions. RESULTS From the 72 studies reviewed, six key risk factor themes emerged through LDA topic modelling. The review identified ototoxicity, primarily caused by cancer treatments and antibiotics, infectious diseases like COVID-19, occupational noise exposure, lifestyle factors, health conditions, biological responses, and age progression as significant risk factors for HL. The highest proportional incidence was found with cancer-related ototoxicity at 55.4% (95%CI: 39.0-70.7), followed closely by ototoxicity from infectious diseases at 50.0% (95%CI: 28.5-71.5). This high proportional incidence suggests the need to explore less destructive therapies and proactively monitor hearing function during treatments. CONCLUSIONS The findings of this review, combined with the synthesis of epidemiological evidence, enhance our understanding of hearing loss (HL) pathogenesis and highlight potential areas for intervention, thereby paving the way for more effective prevention and management of adult-onset hearing loss in our ageing global population.
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Affiliation(s)
- Yvonne Tran
- Macquarie University Hearing Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
| | - Diana Tang
- Macquarie University Hearing Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
| | - Charles Lo
- Australian College of Applied Professions, Sydney, NSW 2000, Australia.
| | - Oonagh Macken
- Department of Linguistics, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
| | - John Newall
- Department of Linguistics, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
| | - Mia Bierbaum
- Australian Institute of Health Innovation, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
| | - Bamini Gopinath
- Macquarie University Hearing Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University, NSW 2109, Australia.
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Gu X, Jiang K, Chen R, Chen Z, Wu X, Xiang H, Huang X, Nan B. Identification of common stria vascularis cellular alteration in sensorineural hearing loss based on ScRNA-seq. BMC Genomics 2024; 25:213. [PMID: 38413848 PMCID: PMC10897997 DOI: 10.1186/s12864-024-10122-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 02/14/2024] [Indexed: 02/29/2024] Open
Abstract
BACKGROUND The stria vascularis (SV), located in the lateral wall of the cochlea, maintains cochlear fluid homeostasis and mechanoelectrical transduction (MET) activity required for sound wave conduction. The pathogenesis of a number of human inheritable deafness syndromes, age related hearing loss, drug-induced ototoxicity and noise-induced hearing loss results from the morphological changes and functional impairments in the development of the SV. In this study, we investigate the implications of intercellular communication within the SV in the pathogenesis of sensorineural hearing loss (SNHL). We aim to identify commonly regulated signaling pathways using publicly available single-cell transcriptomic sequencing (scRNA-seq) datasets. METHODS We analyzed scRNA-seq data, which was derived from studying the cochlear SV in mice with SNHL compared to normal adult mice. After quality control and filtering, we obtained the major cellular components of the mouse cochlear SV and integrated the data. Using Seurat's FindAllMarkers and FindMarkers packages, we searched for novel conservative genes and differential genes. We employed KEGG and GSEA to identify molecular pathways that are commonly altered among different types of SNHL. We utilized pySCENIC to discover new specific regulatory factors in SV subpopulation cells. With the help of CellChat, we identified changes in subpopulation cells showing similar trends across different SNHL types and their alterations in intercellular communication pathways. RESULTS Through the analysis of the integrated data, we discovered new conserved genes to SV specific cells and identified common downregulated pathways in three types of SNHL. The enriched genes for these pathways showing similar trends are primarily associated with the Electron Transport Chain, related to mitochondrial energy metabolism. Using the CellChat package, we further found that there are shared pathways in the incoming signaling of specific intermediate cells in SNHL, and these pathways have common upstream regulatory transcription factor of Nfe2l2. Combining the results from pySCENIC and CellChat, we predicted the transcription factor Nfe2l2 as an upstream regulatory factor for multiple shared cellular pathways in IC. Additionally, it serves as an upstream factor for several genes within the Electron Transport Chain. CONCLUSION Our bioinformatics analysis has revealed that downregulation of the mitochondrial electron transport chain have been observed in various conditions of SNHL. E2f1, Esrrb, Runx1, Yy1, and Gata2 could serve as novel important common TFs regulating the electron transport chain. Adm has emerged as a potential new marker gene for intermediate cells, while Itgb5 and Tesc show promise as potential new marker genes for marginal cells in the SV. These findings offer a new perspective on SV lesions in SNHL and provide additional theoretical evidence for the same drug treatment and prevention of different pathologies of SNHL.
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Affiliation(s)
- Xi Gu
- Department of Otorhinolaryngology, Head and Neck Surgery, the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Institute of Otolaryngology, the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Otorhinolaryngology, Head and Neck Surgery, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Kanglun Jiang
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongshan Hospital, Fudan University, Fenglin Road 180, Xuhui District, Shanghai, 200030, People's Republic of China
| | - Ruru Chen
- Department of Otorhinolaryngology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Zhifeng Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Institute of Otolaryngology, the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Otorhinolaryngology, Head and Neck Surgery, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Xianmin Wu
- Department of Otolaryngology-Head and Neck Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Haijie Xiang
- Department of Otorhinolaryngology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xinsheng Huang
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongshan Hospital, Fudan University, Fenglin Road 180, Xuhui District, Shanghai, 200030, People's Republic of China.
| | - Benyu Nan
- Department of Otorhinolaryngology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
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Lachaux J, Giéré PA, Vuillemin Q, Colléony T, Crambert A, Siegrist S, Parietti-Winkler C, Schwartzbrod PÉ, Andéol G. Long-Term Hearing Loss after Acute Acoustic Trauma in the French Military: A Retrospective Study. Mil Med 2024; 189:e698-e704. [PMID: 37651596 DOI: 10.1093/milmed/usad337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/25/2023] [Accepted: 08/18/2023] [Indexed: 09/02/2023] Open
Abstract
INTRODUCTION Acute acoustic trauma (AAT) is characterized by cochlea-vestibular signs following intense noise exposure, often caused by impulse noise. French military faces a high risk of AAT because of the use of weapons with peak sound levels exceeding 150 dB. Hearing loss (HL) resulting from AAT can have a significant impact on quality of life and operational capacity. The aim of this study was to assess the prevalence of long-term hearing impairment after AAT. MATERIALS AND METHODS The study involved a retrospective review of computer-based patient records from four military medical centers in Northeast France between January 2016 and December 2021. The inclusion criteria required the presence of cochlea-vestibular signs following impulse acoustic exposure and the absence of other causes. Sociodemographic and clinical data were collected, including audiometric data before and after exposure. The primary end point was the presence of a threshold elevation greater than 10 dB between reference and late audiograms. RESULTS A total of 419 patients were included in the analysis, with a majority of males (n = 419; 84.7%) and a mean age of 23.6 yrs. The most common causative agent was the 5.56-mm assault rifle (n = 327; 78.0%). Tinnitus was the most frequent symptom (n = 366; 87.4%), followed by hypoacusis (n = 147; 35.1%) and earache (n = 89; 21.2%). The initial audiograms showed no HL in 31.0% of cases, while the mean deficit across all frequencies was 15.4 dB. All patients received corticosteroid therapy, with a mean duration of 6.0 d. Late audiograms conducted at an average interval of 448.0 d after AAT revealed a prevalence of long-term HL exceeding 20%. Higher doses of corticosteroid therapy (>1 mg/kg) were associated with a reduced frequency of long-term HL. CONCLUSIONS This study highlights the prevalence of long-term hearing impairment after AAT in the French military. The findings emphasize the importance of preventive measures, including proper use of hearing protection devices, and the need for timely diagnosis and treatment. Further research is warranted to explore gender susceptibility to AAT and evaluate the impact of different weapons on AAT characteristics. The study also underscores the potential benefits of higher doses of corticosteroid therapy in reducing the risk of long-term hearing impairment. Overall, the findings contribute to a better understanding of AAT and can inform strategies for its prevention and management in military settings.
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Affiliation(s)
| | | | | | | | - Anna Crambert
- ORL Department, Percy Army Training Hospital, Clamart 92140, France
| | - Sophie Siegrist
- Medical school, University of Lorraine, Vandoeuvre-lès-Nancy 54505, France
| | | | | | - Guillaume Andéol
- French Armed Forces Biomedical Research Institute, Brétigny-sur-Orge 91220, France
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Herb M. NADPH Oxidase 3: Beyond the Inner Ear. Antioxidants (Basel) 2024; 13:219. [PMID: 38397817 PMCID: PMC10886416 DOI: 10.3390/antiox13020219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
Reactive oxygen species (ROS) were formerly known as mere byproducts of metabolism with damaging effects on cellular structures. The discovery and description of NADPH oxidases (Nox) as a whole enzyme family that only produce this harmful group of molecules was surprising. After intensive research, seven Nox isoforms were discovered, described and extensively studied. Among them, the NADPH oxidase 3 is the perhaps most underrated Nox isoform, since it was firstly discovered in the inner ear. This stigma of Nox3 as "being only expressed in the inner ear" was also used by me several times. Therefore, the question arose whether this sentence is still valid or even usable. To this end, this review solely focuses on Nox3 and summarizes its discovery, the structural components, the activating and regulating factors, the expression in cells, tissues and organs, as well as the beneficial and detrimental effects of Nox3-mediated ROS production on body functions. Furthermore, the involvement of Nox3-derived ROS in diseases progression and, accordingly, as a potential target for disease treatment, will be discussed.
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Affiliation(s)
- Marc Herb
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine, University Hospital Cologne, University of Cologne, 50935 Cologne, Germany;
- German Centre for Infection Research, Partner Site Bonn-Cologne, 50931 Cologne, Germany
- Cologne Cluster of Excellence on Cellular Stress Responses in Aging-Associated Diseases (CECAD), 50931 Cologne, Germany
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Wu Y, Zhang J, Liu Q, Miao Z, Chai R, Chen W. Development of Chinese herbal medicine for sensorineural hearing loss. Acta Pharm Sin B 2024; 14:455-467. [PMID: 38322328 PMCID: PMC10840432 DOI: 10.1016/j.apsb.2023.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/16/2023] [Accepted: 10/24/2023] [Indexed: 02/08/2024] Open
Abstract
According to the World Health Organization's world report on hearing, nearly 2.5 billion people worldwide will suffer from hearing loss by 2050, which may contribute to a severe impact on individual life quality and national economies. Sensorineural hearing loss (SNHL) occurs commonly as a result of noise exposure, aging, and ototoxic drugs, and is pathologically characterized by the impairment of mechanosensory hair cells of the inner ear, which is mainly triggered by reactive oxygen species accumulation, inflammation, and mitochondrial dysfunction. Though recent advances have been made in understanding the ability of cochlear repair and regeneration, there are still no effective therapeutic drugs for SNHL. Chinese herbal medicine which is widely distributed and easily accessible in China has demonstrated a unique curative effect against SNHL with higher safety and lower cost compared with Western medicine. Herein we present trends in research for Chinese herbal medicine for the treatment of SNHL, and elucidate their molecular mechanisms of action, to pave the way for further research and development of novel effective drugs in this field.
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Affiliation(s)
- Yunhao Wu
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
| | - Jingwen Zhang
- Department of Otolaryngology-Head and Neck, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Qiuping Liu
- Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Jiangnan University, Wuxi 214000, China
| | - Zhuang Miao
- Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Jiangnan University, Wuxi 214000, China
| | - Renjie Chai
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing 210096, China
- Department of Otolaryngology Head and Neck Surgery, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610000, China
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Science, Beijing 100085, China
- Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing 100069, China
| | - Wenyong Chen
- Department of Otolaryngology-Head and Neck, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
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Perez-Carpena P, Lopez-Escamez JA, Gallego-Martinez Á. A Systematic Review on the Genetic Contribution to Tinnitus. J Assoc Res Otolaryngol 2024; 25:13-33. [PMID: 38334885 PMCID: PMC10907330 DOI: 10.1007/s10162-024-00925-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 12/31/2023] [Indexed: 02/10/2024] Open
Abstract
PURPOSE To assess the available evidence to support a genetic contribution and define the role of common and rare variants in tinnitus. METHODS After a systematic search and quality assessment, 31 records including 383,063 patients were selected (14 epidemiological studies and 17 genetic association studies). General information on the sample size, age, sex, tinnitus prevalence, severe tinnitus distribution, and sensorineural hearing loss was retrieved. Studies that did not include data on hearing assessment were excluded. Relative frequencies were used for qualitative variables to compare different studies and to obtain average values. Genetic variants and genes were listed and clustered according to their potential role in tinnitus development. RESULTS The average prevalence of tinnitus estimated from population-based studies was 26.3% for any tinnitus, and 20% of patients with tinnitus reported it as an annoying symptom. One study has reported population-specific differences in the prevalence of tinnitus, the white ancestry being the population with a higher prevalence. Genome-wide association studies have identified and replicated two common variants in the Chinese population (rs2846071; rs4149577) in the intron of TNFRSF1A, associated with noise-induced tinnitus. Moreover, gene burden analyses in sequencing data from Spanish and Swede patients with severe tinnitus have identified and replicated ANK2, AKAP9, and TSC2 genes. CONCLUSIONS The genetic contribution to tinnitus is starting to be revealed and it shows population-specific effects in European and Asian populations. The common allelic variants associated with tinnitus that showed replication are associated with noise-induced tinnitus. Although severe tinnitus has been associated with rare variants with large effect, their role on hearing or hyperacusis has not been established.
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Affiliation(s)
- Patricia Perez-Carpena
- Otology and Neurotology Group CTS495, Division of Otolaryngology, Department of Surgery, Instituto de Investigación Biosanitaria, Ibs.GRANADA, Universidad de Granada, Granada, Spain.
- Sensorineural Pathology Programme, Centro de Investigación Biomédica en Red en Enfermedades Raras, CIBERER, Madrid, Spain.
- Department of Otolaryngology, Instituto de Investigación Biosanitaria Ibs.GRANADA, Hospital Universitario Virgen de Las Nieves, Granada, Spain.
| | - Jose A Lopez-Escamez
- Otology and Neurotology Group CTS495, Division of Otolaryngology, Department of Surgery, Instituto de Investigación Biosanitaria, Ibs.GRANADA, Universidad de Granada, Granada, Spain.
- Sensorineural Pathology Programme, Centro de Investigación Biomédica en Red en Enfermedades Raras, CIBERER, Madrid, Spain.
- Meniere's Disease Neuroscience Research Program, Faculty of Medicine & Health, School of Medical Sciences, The Kolling Institute, University of Sydney, Sydney, NSW, Australia.
| | - Álvaro Gallego-Martinez
- Otology and Neurotology Group CTS495, Division of Otolaryngology, Department of Surgery, Instituto de Investigación Biosanitaria, Ibs.GRANADA, Universidad de Granada, Granada, Spain
- Sensorineural Pathology Programme, Centro de Investigación Biomédica en Red en Enfermedades Raras, CIBERER, Madrid, Spain
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12
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McGovern MM, Hosamani IV, Niu Y, Nguyen KY, Zong C, Groves AK. Expression of Atoh1, Gfi1, and Pou4f3 in the mature cochlea reprograms nonsensory cells into hair cells. Proc Natl Acad Sci U S A 2024; 121:e2304680121. [PMID: 38266052 PMCID: PMC10835112 DOI: 10.1073/pnas.2304680121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 12/08/2023] [Indexed: 01/26/2024] Open
Abstract
Mechanosensory hair cells of the mature mammalian organ of Corti do not regenerate; consequently, loss of hair cells leads to permanent hearing loss. Although nonmammalian vertebrates can regenerate hair cells from neighboring supporting cells, many humans with severe hearing loss lack both hair cells and supporting cells, with the organ of Corti being replaced by a flat epithelium of nonsensory cells. To determine whether the mature cochlea can produce hair cells in vivo, we reprogrammed nonsensory cells adjacent to the organ of Corti with three hair cell transcription factors: Gfi1, Atoh1, and Pou4f3. We generated numerous hair cell-like cells in nonsensory regions of the cochlea and new hair cells continued to be added over a period of 9 wk. Significantly, cells adjacent to reprogrammed hair cells expressed markers of supporting cells, suggesting that transcription factor reprogramming of nonsensory cochlear cells in adult animals can generate mosaics of sensory cells like those seen in the organ of Corti. Generating such sensory mosaics by reprogramming may represent a potential strategy for hearing restoration in humans.
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Affiliation(s)
- Melissa M McGovern
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - Ishwar V Hosamani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Yichi Niu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Ken Y Nguyen
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - Chenghang Zong
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Andrew K Groves
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
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13
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Roth S, Müller FU, Angermeier J, Hemmert W, Zirn S. Effect of a processing delay between direct and delayed sound in simulated open fit hearing aids on speech intelligibility in noise. Front Neurosci 2024; 17:1257720. [PMID: 38264492 PMCID: PMC10805375 DOI: 10.3389/fnins.2023.1257720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 11/28/2023] [Indexed: 01/25/2024] Open
Abstract
Introduction Subjects with mild to moderate hearing loss today often receive hearing aids (HA) with open-fitting (OF). In OF, direct sound reaches the eardrums with minimal damping. Due to the required processing delay in digital HA, the amplified HA sound follows some milliseconds later. This process occurs in both ears symmetrically in bilateral HA provision and is likely to have no or minor detrimental effect on binaural hearing. However, the delayed and amplified sound are only present in one ear in cases of unilateral hearing loss provided with one HA. This processing alters interaural timing differences in the resulting ear signals. Methods In the present study, an experiment with normal-hearing subjects to investigate speech intelligibility in noise with direct and delayed sound was performed to mimic unilateral and bilateral HA provision with OF. Results The outcomes reveal that these delays affect speech reception thresholds (SRT) in the unilateral OF simulation when presenting speech and noise from different spatial directions. A significant decrease in the median SRT from -18.1 to -14.7 dB SNR is observed when typical HA processing delays are applied. On the other hand, SRT was independent of the delay between direct and delayed sound in the bilateral OF simulation. Discussion The significant effect emphasizes the development of rapid processing algorithms for unilateral HA provision.
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Affiliation(s)
- Sebastian Roth
- Department of Electrical Engineering, Medical Engineering and Computer Science, Peter Osypka Institute of Medical Engineering, Offenburg University of Applied Sciences, Offenburg, Germany
- Department of Electrical and Computer Engineering, Munich Institute of Biomedical Engineering, Technical University of Munich, Munich, Germany
| | - Franz-Ullrich Müller
- Department of Electrical Engineering, Medical Engineering and Computer Science, Peter Osypka Institute of Medical Engineering, Offenburg University of Applied Sciences, Offenburg, Germany
- Department of Electrical and Computer Engineering, Munich Institute of Biomedical Engineering, Technical University of Munich, Munich, Germany
| | - Julian Angermeier
- Department of Electrical Engineering, Medical Engineering and Computer Science, Peter Osypka Institute of Medical Engineering, Offenburg University of Applied Sciences, Offenburg, Germany
| | - Werner Hemmert
- Department of Electrical and Computer Engineering, Munich Institute of Biomedical Engineering, Technical University of Munich, Munich, Germany
| | - Stefan Zirn
- Department of Electrical Engineering, Medical Engineering and Computer Science, Peter Osypka Institute of Medical Engineering, Offenburg University of Applied Sciences, Offenburg, Germany
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14
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Shin S, Nam HY. Characteristics of brain glucose metabolism and metabolic connectivity in noise-induced hearing loss. Sci Rep 2023; 13:21889. [PMID: 38081979 PMCID: PMC10713681 DOI: 10.1038/s41598-023-48911-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 12/01/2023] [Indexed: 12/18/2023] Open
Abstract
The purpose of this study was to evaluate the differences in cerebral glucose metabolism and metabolic connectivity between noise-induced hearing loss (NIHL) subjects and normal subjects. Eighty-nine subjects who needed close observation for NIHL or were diagnosed with NIHL and 89 normal subjects were enrolled. After pre-processing of positron emission tomography images including co-registration, spatial normalization, and smoothing, a two-sample t-test was conducted to compare cerebral glucose metabolism between the two groups. To evaluate metabolic connectivity between two groups, BRAPH-BRain Analysis using graPH theory, a software package to perform graph theory analysis of the brain connectome was used. NIHL subjects showed hypometabolism compared to normal subjects in both insulae (x - 38, y - 18, z 4; × 42, y - 12, z 4) and right superior temporal gyrus (× 44, y 16, z - 20). No brain regions showed hypermetabolism in the NIHL subjects. In metabolic connectivity analysis, NIHL subjects showed decreased average strength, global efficiency, local efficiency, and mean clustering coefficient when compared with normal subjects. Decreased glucose metabolism and metabolic connectivity in NIHL subject might reflect decreased auditory function. It might be characteristic of sensorineural hearing loss.
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Affiliation(s)
- Seunghyeon Shin
- Department of Nuclear Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Hyun-Yeol Nam
- Department of Nuclear Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
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15
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Suzuki J, Hemmi T, Maekawa M, Watanabe M, Inada H, Ikushima H, Oishi T, Ikeda R, Honkura Y, Kagawa Y, Kawase T, Mano N, Owada Y, Osumi N, Katori Y. Fatty acid binding protein type 7 deficiency preserves auditory function in noise-exposed mice. Sci Rep 2023; 13:21494. [PMID: 38057582 PMCID: PMC10700610 DOI: 10.1038/s41598-023-48702-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023] Open
Abstract
Fatty acid-binding protein 7 (FABP7) is vital for uptake and trafficking of fatty acids in the nervous system. To investigate the involvement of FABP7 in noise-induced hearing loss (NIHL) pathogenesis, we used Fabp7 knockout (KO) mice generated via CRISPR/Cas9 in the C57BL/6 background. Initial auditory brainstem response (ABR) measurements were conducted at 9 weeks, followed by noise exposure at 10 weeks. Subsequent ABRs were performed 24 h later, with final measurements at 12 weeks. Inner ears were harvested 24 h after noise exposure for RNA sequencing and metabolic analyses. We found no significant differences in initial ABR measurements, but Fabp7 KO mice showed significantly lower thresholds in the final ABR measurements. Hair cell survival was also enhanced in Fabp7 KO mice. RNA sequencing revealed that genes associated with the electron transport chain were upregulated or less impaired in Fabp7 KO mice. Metabolomic analysis revealed various alterations, including decreased glutamate and aspartate in Fabp7 KO mice. In conclusion, FABP7 deficiency mitigates cochlear damage following noise exposure. This protective effect was supported by the changes in gene expression of the electron transport chain, and in several metabolites, including excitotoxic neurotransmitters. Our study highlights the potential therapeutic significance of targeting FABP7 in NIHL.
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Affiliation(s)
- Jun Suzuki
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan.
| | - Tomotaka Hemmi
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Masamitsu Maekawa
- Department of Pharmaceutical Sciences, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Masahiro Watanabe
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Hitoshi Inada
- Department of Developmental Neuroscience, Centers for Neuroscience, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Hiroyuki Ikushima
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Tetsuya Oishi
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Ryoukichi Ikeda
- Department of Otolaryngology, Head and Neck Surgery, Iwate Medical University School of Medicine, 19-1 Odori, Yahaba, Shiwa, 020-8505, Japan
| | - Yohei Honkura
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Yoshiteru Kagawa
- Department of Organ Anatomy, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Tetsuaki Kawase
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Nariyasu Mano
- Department of Pharmaceutical Sciences, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
- Graduate School of Pharmaceutical Sciences, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Yuji Owada
- Department of Organ Anatomy, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, Centers for Neuroscience, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Yukio Katori
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
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16
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Grinn SK, Trevino M, Lobarinas E. Noise-Induced Hearing Threshold Shift Correlated with Body Weight and External-Ear Amplification in Chinchilla: a Preliminary Analysis. J Assoc Res Otolaryngol 2023; 24:563-574. [PMID: 38010580 PMCID: PMC10752858 DOI: 10.1007/s10162-023-00913-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 10/11/2023] [Indexed: 11/29/2023] Open
Abstract
BACKGROUND External-ear amplification (EEA) has been shown to vary from 5-19 dB-A in large datasets of pediatric, adolescent, and adult human participants. However, variable EEA is an overlooked characteristic that likely plays a role in individual noise-induced hearing loss (NIHL) susceptibility. A noise exposure varying 5-19 dB-A translates to high-EEA individuals theoretically experiencing 3-4 times greater NIHL risk than low-EEA individuals. OBJECTIVE The purpose of this preliminary analysis was to test the hypothesis that higher EEA is correlated with increased noise-induced threshold shift susceptibility. DESIGN Nine chinchillas were exposed to 4-kHz octave-band noise at 89 dB-SPL for 24 h. Auditory brainstem response thresholds were obtained pre-exposure, 24-h post-exposure, and 4-week post-exposure. Relationships between EEA and threshold shift were analyzed. RESULTS Open-ear EEA ranged 11-19 dB-SPL, and occluded-ear EEA ranged 10-21 dB-SPL. Higher occluded-ear EEA was correlated with increased NIHL susceptibility (p = 0.04), as was lower body weight (p = 0.01). Male animals exhibited more threshold shift than female animals (p = 0.02), lower body weight than female animals (p = 0.02), and higher occluded-ear EEA (male mean = 18 dB; female mean = 15 dB). CONCLUSIONS Taken together, increased threshold shift susceptibility was observed in the smallest animals, animals with the highest occluded-ear EEA, and in male animals (which tended to have higher occluded-ear EEA). Given the established relationship between smaller body size and higher occluded-ear EEA, these preliminary results suggest that body size (and occluded-ear EEA; a function of body size) could be a potential, underlying driver of NIHL susceptibility differences, rather than true sex differences.
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Affiliation(s)
- Sarah K Grinn
- College of Health Professions, Central Michigan University, Mount Pleasant, MI, USA.
| | - Monica Trevino
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, TX, USA
| | - Edward Lobarinas
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Dallas, TX, USA
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17
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Sahin Ceylan D, Sacli Y, Gultekin G, Avsar B, Ozver AG. Do Flights Affect Hearing in Hot Air Balloon Pilots? Am J Audiol 2023:1-10. [PMID: 37992408 DOI: 10.1044/2023_aja-23-00126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2023] Open
Abstract
PURPOSE This study aimed to reveal occupational effects on the hearing of hot air balloon (HAB) pilots and examine the relationship between the duration of experience and these effects. METHOD This study included 31 male HAB pilots and a control group of 32 male participants. Tympanometry, eustachian tube function (ETF) test, pure-tone audiometry, and transient evoked otoacoustic emission (TEOAE) tests were performed. RESULTS Pure-tone audiometry results were significantly worse at 125, 500, and 6000 Hz in the right ear and 125, 500, 4000, and 6000 Hz in the left ear in the HAB group than the control group. Although tympanometry evaluation parameters did not differ between the HAB and control groups, ETF test was significantly worse in the HAB group than the controls bilaterally. TEOAE results were significantly worse at 1000, 2000, and 4000 Hz in the right ear and 4000 Hz in the left ear in the HAB group than the controls. There was a significant positive correlation for 125, 4000, 6000, and 8000 Hz between the duration of experience and right ear hearing thresholds. For the left ear, the duration of experience showed a significant positive correlation at 3000, 4000, 6000, and 8000 Hz. When the relationship between the duration of experience and TEOAE results was evaluated, a significant negative correlation was found at 4000 Hz in the left ear. CONCLUSION In HAB pilots, in whom eustachian tube dysfunction is quite common, noise and high altitude affected hearing, especially low and high frequencies, and the duration of experience was found to be associated with hearing thresholds.
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Affiliation(s)
- Didem Sahin Ceylan
- Faculty of Health Sciences, Department of Audiology, Üsküdar University, Istanbul, Turkey
| | - Yeter Sacli
- Faculty of Health Sciences, Department of Audiology, Üsküdar University, Istanbul, Turkey
- Department of Audiology and Speech Disorders, Institute of Health Sciences, Marmara University, Istanbul, Turkey
| | - Gokce Gultekin
- Faculty of Health Sciences, Department of Audiology, Üsküdar University, Istanbul, Turkey
- Department of Audiology, Language and Speech Disorders, Institute of Graduate Studies, Istanbul University-Cerrahpasa, Turkey
| | - Busemnaz Avsar
- Faculty of Health Sciences, Department of Audiology, Üsküdar University, Istanbul, Turkey
| | - Aleyna Goncu Ozver
- Faculty of Health Sciences, Department of Audiology, Üsküdar University, Istanbul, Turkey
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18
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Themann CL, Masterson EA, Peterson JS, Murphy WJ. Preventing Occupational Hearing Loss: 50 Years of Research and Recommendations from the National Institute for Occupational Safety and Health. Semin Hear 2023; 44:351-393. [PMID: 37818146 PMCID: PMC10562059 DOI: 10.1055/s-0043-1769499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023] Open
Abstract
For more than 50 years, the National Institute for Occupational Safety and Health (NIOSH), part of the United States (U.S.) Centers for Disease Control and Prevention (CDC), has been actively working to reduce the effects of noise and ototoxic chemicals on worker hearing. NIOSH has pioneered basic and applied research on occupational hearing risks and preventive measures. The Institute has issued recommendations and promoted effective interventions through mechanisms ranging from formal criteria documents to blogs and social media. NIOSH has conducted surveillance and published statistics to guide policy and target prevention efforts. Over the past five decades, substantial progress has been made in raising awareness of noise as a hazard, reducing the risk of occupational hearing loss, improving the use of hearing protection, and advancing measurement and control technologies. Nevertheless, noise remains a prevalent workplace hazard and occupational hearing loss is still one of the most common work-related conditions. NIOSH continues to work toward preventing the effects of noise and ototoxicants at work and has many resources to assist audiologists in their hearing loss prevention efforts.
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Affiliation(s)
- Christa L. Themann
- Noise and Bioacoustics Team, National Institute for Occupational Safety and Health, Cincinnati, Ohio
| | - Elizabeth A. Masterson
- Division of Field Studies and Engineering, National Institute for Occupational Safety and Health, Cincinnati, Ohio
| | - Jeffrey Shawn Peterson
- Pittsburgh Mining Research Division, National Institute for Occupational Safety and Health, Pittsburgh, Pennsylvania
| | - William J. Murphy
- Noise and Bioacoustics Team, National Institute for Occupational Safety and Health, Cincinnati, Ohio
- Stephenson and Stephenson Research and Consulting, LLC, Batavia, Ohio
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19
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Zhuang H, Li Q, Sun C, Xu D, Gan G, Zhang C, Chen C, Yuan Y, Liu L, Xiao Y, Yao X, Wang C, Kang X, Yang C, Zhao J, Chen W, Wang J, Li J, Luo C, Wang J, Jia X, Yu Z, Liu L. Voluntary wheel exercise ameliorates cognitive impairment, hippocampal neurodegeneration and microglial abnormalities preceded by demyelination in a male mouse model of noise-induced hearing loss. Brain Behav Immun 2023; 114:325-348. [PMID: 37683962 DOI: 10.1016/j.bbi.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/23/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023] Open
Abstract
Acquired peripheral hearing loss (APHL) in midlife has been identified as the greatest modifiable risk factor for dementia; however, the pathophysiological neural mechanisms linking APHL with an increased risk of dementia remain to be elucidated. Here, in an adult male mouse model of noise-induced hearing loss (NIHL), one of the most common forms of APHL, we demonstrated accelerated age-related cognitive decline and hippocampal neurodegeneration during a 6-month follow-up period, accompanied by progressive hippocampal microglial aberrations preceded by immediate-onset transient elevation in serum glucocorticoids and delayed-onset sustained myelin disruption in the hippocampus. Pretreatment with the glucocorticoid receptor antagonist RU486 before stressful noise exposure partially mitigated the early activation of hippocampal microglia, which were present at 7 days post noise exposure (7DPN), but had no impact on later microglial aberrations, hippocampal neurodegeneration, or cognitive decline exhibited at 1 month post noise exposure (1MPN). One month of voluntary wheel exercise following noise exposure barely affected either the hearing threshold shift or hippocampal myelin changes but effectively countered cognitive impairment and the decline in hippocampal neurogenesis in NIHL mice at 1MPN, paralleled by the normalization of microglial morphology, which coincided with a reduction in microglial myelin inclusions and a restoration of microglial hypoxia-inducible factor-1α (HIF1α) expression. Our results indicated that accelerated cognitive deterioration and hippocampal neuroplastic decline following NIHL are most likely driven by the maladaptive response of hippocampal microglia to myelin damage secondary to hearing loss, and we also demonstrated the potential of voluntary physical exercise as a promising and cost-effective strategy to alleviate the detrimental impact of APHL on cognitive function and thus curtail the high and continuously increasing global burden of dementia. Furthermore, the findings of the present study highlight the contribution of myelin debris overload to microglial malfunction and identify the microglial HIF1α-related pathway as an attractive candidate for future comprehensive investigation to obtain a more definitive picture of the underlying mechanisms linking APHL and dementia.
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Affiliation(s)
- Hong Zhuang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Qian Li
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Congli Sun
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Dan Xu
- School of Public Health, Southeast University, Nanjing 210009, China
| | - Guangming Gan
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chenchen Zhang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chen Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Yang Yuan
- Department of Endocrinology, Zhongda Hospital, Medical School, Southeast University, Nanjing 210009, China
| | - Linchen Liu
- Department of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China
| | - Yu Xiao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiuting Yao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Conghui Wang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiaoming Kang
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Chenxi Yang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Jingyi Zhao
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Wenhao Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jiatang Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jinyu Li
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Caichen Luo
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jie Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Xirui Jia
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Zhehao Yu
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Lijie Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China.
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20
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Delaney DS, Liew LJ, Lye J, Atlas MD, Wong EYM. Overcoming barriers: a review on innovations in drug delivery to the middle and inner ear. Front Pharmacol 2023; 14:1207141. [PMID: 37927600 PMCID: PMC10620978 DOI: 10.3389/fphar.2023.1207141] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 10/02/2023] [Indexed: 11/07/2023] Open
Abstract
Despite significant advances in the development of therapeutics for hearing loss, drug delivery to the middle and inner ear remains a challenge. As conventional oral or intravascular administration are ineffective due to poor bioavailability and impermeability of the blood-labyrinth-barrier, localized delivery is becoming a preferable approach for certain drugs. Even then, localized delivery to the ear precludes continual drug delivery due to the invasive and potentially traumatic procedures required to access the middle and inner ear. To address this, the preclinical development of controlled release therapeutics and drug delivery devices have greatly advanced, with some now showing promise clinically. This review will discuss the existing challenges in drug development for treating the most prevalent and damaging hearing disorders, in particular otitis media, perforation of the tympanic membrane, cholesteatoma and sensorineural hearing loss. We will then address novel developments in drug delivery that address these including novel controlled release therapeutics such as hydrogel and nanotechnology and finally, novel device delivery approaches such as microfluidic systems and cochlear prosthesis-mediated delivery. The aim of this review is to investigate how drugs can reach the middle and inner ear more efficiently and how recent innovations could be applied in aiding drug delivery in certain pathologic contexts.
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Affiliation(s)
- Derek S. Delaney
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA, Australia
- Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, WA, Australia
| | - Lawrence J. Liew
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA, Australia
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA, Australia
| | - Joey Lye
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA, Australia
| | - Marcus D. Atlas
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA, Australia
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA, Australia
- Faculty of Health Sciences, Curtin Medical School, Curtin University, Bentley, WA, Australia
| | - Elaine Y. M. Wong
- Hearing Therapeutics, Ear Science Institute Australia, Nedlands, WA, Australia
- Centre for Ear Sciences, Medical School, The University of Western Australia, Nedlands, WA, Australia
- Faculty of Health Sciences, Curtin Medical School, Curtin University, Bentley, WA, Australia
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Snapp HA, Vanlooy L, Kuzbyt B, Kolberg C, Laffitte-Lopez D, Rajguru S. Peripheral vestibular loss in noise-exposed firefighters. Front Integr Neurosci 2023; 17:1236661. [PMID: 37849955 PMCID: PMC10577377 DOI: 10.3389/fnint.2023.1236661] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 08/25/2023] [Indexed: 10/19/2023] Open
Abstract
Introduction Occupational workers are increasingly aware of the risk of noise overexposure to the auditory system but lack awareness about potential risks to the vestibular system. The purpose of this study was to investigate changes in vestibular end organ function in a known at-risk noise-exposed population, firefighters compared to age- and sex-matched controls using electrophysiologic measures of cervical vestibular evoked myogenic potentials (cVEMP). Methods A cross-sectional observational study compared cVEMP response characteristics in 38 noise-exposed firefighters. Firefighters were grouped by years of exposure in the fire service. The cVEMP responses were compared within firefighter groups and between firefighters and age- and sex-matched controls. Dependent variables included the response characteristics of amplitude, latency and threshold. Results cVEMP response amplitudes were significantly decreased in firefighters compared to their age- and sex-matched controls. Threshold of the cVEMP responses were significantly higher in firefighters compared to controls and firefighters had a higher incidence of absent cVEMP responses compared to controls. Response amplitudes decreased with increasing years in the fire-service at an increased rate compared to their age- and sex-matched controls. Latency of the cVEMP response was not significantly different in firefighters compared to controls. These findings are consistent with both animal and human studies suggesting noise-induced changes in the sacculocollic pathway. Discussion In the absence of any reported vestibular symptoms or auditory indicators of noise-induced hearing loss, these early effects on the vestibular system point to a potential hidden vestibular loss.
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Affiliation(s)
- Hillary Anne Snapp
- Department of Otolaryngology, University of Miami, Miami, FL, United States
| | - Lindsey Vanlooy
- Department of Otolaryngology, University of Miami, Miami, FL, United States
| | - Brianna Kuzbyt
- Department of Otolaryngology, University of Miami, Miami, FL, United States
| | - Courtney Kolberg
- Department of Otolaryngology, University of Miami, Miami, FL, United States
| | | | - Suhrud Rajguru
- Department of Otolaryngology, University of Miami, Miami, FL, United States
- Department of Biomedical Engineering, University of Miami, Miami, FL, United States
- Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, FL, United States
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Rasidi WNA, Seluakumaran K, Jamaluddin SA. Simplified cochlear frequency selectivity measure for sensorineural hearing loss screening: comparison with digit triplet test (DTT) and shortened speech, spatial and qualities of hearing scale (SSQ) questionnaire. Eur Arch Otorhinolaryngol 2023; 280:4391-4400. [PMID: 36988687 DOI: 10.1007/s00405-023-07929-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023]
Abstract
PURPOSE Pure-tone audiometry (PTA) is the gold standard for screening and diagnosis of hearing loss but is not always accessible. This study evaluated a simplified cochlear frequency selectivity (FS) measure as an alternative option to screen for early frequency-specific sensorineural hearing loss (SNHL). METHODS FS measures at 1 and 4 kHz center frequencies were obtained using a custom-made software in normal-hearing (NH), slight SNHL and mild-to-moderate SNHL subjects. For comparison, subjects were also assessed with the Malay Digit Triplet Test (DTT) and the shortened Malay Speech, Spatial and Qualities of Hearing Scale (SSQ) questionnaire. RESULTS Compared to DTT and SSQ, the FS measure at 4 kHz was able to distinguish NH from slight and mild-to-moderate SNHL subjects, and was strongly correlated with their thresholds in quiet determined separately in 1-dB step sizes at the similar test frequency. Further analysis with receiver operating characteristic (ROC) curves indicated area under the curve (AUC) of 0.77 and 0.83 for the FS measure at 4 kHz when PTA thresholds of NH subjects were taken as ≤ 15 dB HL and ≤ 20 dB HL, respectively. At the optimal FS cut-off point for 4 kHz, the FS measure had 77.8% sensitivity and 86.7% specificity to detect 20 dB HL hearing loss. CONCLUSION FS measure was superior to DTT and SSQ questionnaire in detecting early frequency-specific threshold shifts in SNHL subjects, particularly at 4 kHz. This method could be used for screening subjects at risk of noise-induced hearing loss.
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Affiliation(s)
- Wan Nur Asyiqin Rasidi
- Auditory Lab, Department of Physiology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Kumar Seluakumaran
- Auditory Lab, Department of Physiology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Saiful Adli Jamaluddin
- Kulliyyah of Allied Health Sciences, International Islamic University of Malaysia, Kuantan, Pahang, Malaysia
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Vaddamanu SK, Alhamoudi FH, Binduhayyim RIH, AlJameel AH, Alwadi MAM, Di Blasio M, Cicciù M, Minervini G. Assessment of hearing performance of dental technicians due to the professional noise exposure. BMC Oral Health 2023; 23:685. [PMID: 37737170 PMCID: PMC10515415 DOI: 10.1186/s12903-023-03392-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/06/2023] [Indexed: 09/23/2023] Open
Abstract
BACKGROUND Some of the noise-intensive processes in dental laboratories include the finishing of crowns, bridges, and removable partial dentures; blowing out workpieces with steam and compressed air; and deflating casting rings. High sound pressure levels are also present in dental vibrators, polishing equipment, and sandblasters. The aim of this study was to Evaluation of the effect of noise production in dental technology laboratory on dental technician hearing capacity. METHODS For this cross-sectional study, a total of 120 dental technicians were chosen. Otoscopic evaluation and the Weber test were used to establish if they had sensorineural or transmission hearing loss at 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz, respectively. Then an OAER (objective auditory evoked response) and PTA (clinical aurimeter) test were administered (Neurosoft, Russia). The whole procedure was carried out by an audiologist and an ENT specialist. RESULTS The PTA results showed that the patient had mild hearing impairment overall, with the loss being more severe in the left ear than in the right. The OAE test results revealed that in-ear of the left side, 84.5% of subjects passed and 15.5% of subjects struggled and were referred to an ear specialist, whereas in the right ear, 82.7% of subjects passed and 17.3% struggled and were referred to an ear specialist. According to this study, in a right-handed study participant, the ear on the left side is more vulnerable than the right side. Differences in the mean hearing threshold at 4000 and 6000 Hz in the left ear were statistically significant in the groups of workers with eleven to fifteen years of practical experience and twenty-one to twenty-five years of practical experience, respectively (Minervini, et al. J Clin Med 12:2652, 2023). CONCLUSIONS A statistically meaningful threshold shift from 4000 to 6000 Hz is observed as the working experience grows, and this is suggestive of sensorineural hearing impairment brought on by the noisy dental environment.
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Affiliation(s)
- Sunil Kumar Vaddamanu
- Department of Dental Technology, College of Applied Medical Sciences, King Khalid University, 61421, Abha, Saudi Arabia.
| | - Fahad Hussain Alhamoudi
- Department of Dental Technology, College of Applied Medical Sciences, King Khalid University, 61421, Abha, Saudi Arabia
| | - Rayan Ibrahim H Binduhayyim
- Department of Dental Technology, College of Applied Medical Sciences, King Khalid University, 61421, Abha, Saudi Arabia
| | - AlBandary Hassan AlJameel
- Department of Periodontics and Community Dentistry, College of Dentistry, King Saud University, 11451, Riyadh, Saudi Arabia
| | - Maram Ali M Alwadi
- Dental Health Department, College of Applied Medical Sciences, King Saud University, 11451, Riyadh, Saudi Arabia
| | - Marco Di Blasio
- Department of Medicine and Surgery, University Center of Dentistry,, University of Parma, 43126, Parma, Italy.
| | - Marco Cicciù
- Department of Biomedical and Surgical and Biomedical Sciences, Catania University, 95123, Catania, Italy
| | - Giuseppe Minervini
- Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania, Luigi Vanvitelli, 80138, Naples, Italy.
- Saveetha Dental College & Hospitals Saveetha Institute of Medical & Technical Sciences, Saveetha University, Chennai, India.
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Joseph AR, MacGregor AJ, Dougherty AL. Pre-Existing Audiometric Hearing Loss is a Predictor of Significant Threshold Shift Following Injury During Combat Deployment. Ear Hear 2023; 44:1173-1181. [PMID: 37018078 DOI: 10.1097/aud.0000000000001359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023]
Abstract
OBJECTIVES Military personnel are exposed to multiple risk factors for hearing loss, particularly on the battlefield. The objective of this study was to determine whether pre-existing hearing loss predicted hearing threshold shift in male U.S. military personnel following injury during combat deployment. DESIGN This was a retrospective cohort study with 1573 male military personnel physically injured in Operations Enduring and Iraqi Freedom between 2004 and 2012. Audiograms before and after injury were analyzed and used to calculate significant threshold shift (STS), defined as a 30 dB or greater change in the sum of hearing thresholds at 2000, 3000, and 4000 Hz in either ear on the postinjury audiogram, relative to the same frequencies on the preinjury audiogram. RESULTS Twenty-five percent (n = 388) of the sample had preinjury hearing loss, which mostly occurred in the higher frequencies (i.e., 4000 and 6000 Hz). The prevalence of postinjury STS ranged from 11.7% to 33.3% as preinjury hearing level moved from better to worse. In multivariable logistic regression, preinjury hearing loss was a predictor of STS, and there was a dose-response relationship between severity of preinjury hearing threshold and postinjury STS, specifically for preinjury hearing levels of 40 to 45 dBHL (odds ratio [OR] = 1.99; 95% confidence interval [CI] = 1.03 to 3.88), 50 to 55 dBHL (OR = 2.33; 95% CI = 1.17 to 4.64), and >55 dBHL (OR = 3.77; 95% CI = 2.25 to 6.34). CONCLUSIONS These findings suggest that better preinjury hearing provides increased resistance to threshold shift than impaired preinjury hearing. Although STS is calculated using 2000 to 4000 Hz, clinicians must closely attend to the pure-tone response at 6000 Hz and use this test frequency to identify service members at-risk for STS prior to combat deployment.
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Affiliation(s)
- Antony R Joseph
- Hearing Loss Prevention Laboratory, Communication Sciences and Disorders Department, Illinois State University, Normal, Illinois, USA
- Leidos, Inc., San Diego, California, USA
| | - Andrew J MacGregor
- Medical Modeling, Simulation, and Mission Support Department, Naval Health Research Center, San Diego, California, USA
| | - Amber L Dougherty
- Leidos, Inc., San Diego, California, USA
- Medical Modeling, Simulation, and Mission Support Department, Naval Health Research Center, San Diego, California, USA
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Jin HR, Kim D, Rim HS, Yeo SG. Acoustic differences in tinnitus between noise-induced and non-noise-induced hearing loss. Acta Otolaryngol 2023; 143:766-771. [PMID: 37897331 DOI: 10.1080/00016489.2023.2266471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 09/26/2023] [Indexed: 10/30/2023]
Abstract
BACKGROUND Tinnitus, the perception of sound without external stimuli, varies across hearing loss types. The present study compared the acoustic characteristics of tinnitus in patients with noise-induced hearing loss (NIHL) and in those with hearing loss unrelated to noise exposure. OBJECTIVE This study compared the acoustic characteristics of tinnitus in patients with noise-induced and non-noise-induced hearing loss. METHODS A total of 403 patients with tinnitus were divided into those with noise-induced and non-noise-induced hearing loss. Patients were evaluated by pure tone audiometry (PTA), tinnitogram, transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and auditory brainstem evoked response (ABR) tests. RESULTS Patients with NIHL exhibited significantly higher hearing thresholds across all frequencies (125-8000 Hz) (p < .05) and reported significantly higher tinnitus intensity (p < .05). Otoacoustic emission tests showed that response rates were significantly lower (p < .05), and ABR tests found that latency periods were significantly more prolonged (p < .05), in patients with NIHL. CONCLUSIONS Tinnitus differs acoustically between patients with NIHL and those with non-noise-induced hearing loss, with specific patterns of intensity and auditory responses. These findings emphasize the need for tailoring the management of tinnitus according to the underlying type of hearing loss.
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Affiliation(s)
- Hye Rim Jin
- Department of Otorhinolaryngology Head & Neck Surgery, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Republic of Korea
| | - Dokyoung Kim
- Department of Anatomy and Neurobiology, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Hwa Sung Rim
- Department of Otorhinolaryngology Head & Neck Surgery, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Republic of Korea
| | - Seung Geun Yeo
- Department of Otorhinolaryngology Head & Neck Surgery, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Republic of Korea
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DeJonckere PH, Lebacq J. Asymmetry of Occupational Noise Induced Hearing Loss: An Electrophysiological Approach. Int Arch Otorhinolaryngol 2023; 27:e499-e510. [PMID: 37564477 PMCID: PMC10411239 DOI: 10.1055/s-0042-1750766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 05/15/2022] [Indexed: 03/31/2023] Open
Abstract
Introduction The question as to whether occupational noise exposure causes symmetrical or asymmetrical hearing loss is still controversial and incompletely understood. Objective Two electrophysiological methods (cortical evoked response audiometry: CERA and auditory steady state responses: ASSR) were used to address this issue. Method 156 subjects with a well-documented history of noise exposure, a wide range of noise induced hearing loss (NIHL) and without middle ear pathology underwent both a CERA and an ASSR examination in the context of an exhaustive medicolegal expert assessment intended for possible compensation. Results Whatever the method (CERA or ASSR), the average electrophysiological hearing thresholds (1-2-3 kHz) are significantly worse in the left ear. The right - left differences in CERA and ASSR thresholds are strongly correlated with each other. No significant effect of frequency is found. No correlation is observed between right - left differences in hearing thresholds and either age or degree of hearing loss. Conclusion In NIHL, there is an actual average right - left difference of about 2.23 dB, i.e., 3.2%, the left ear being more impaired.
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Affiliation(s)
| | - Jean Lebacq
- University of Louvain, Neurosciences, Brussels, Belgium
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27
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Liu S, Zou H, Lei S, Xin J, Qian P, Liu Y, Chen Y, Yu K, Zhang M. The role of kurtosis and kurtosis-adjusted energy metric in occupational noise-induced hearing loss among metal manufacturing workers. Front Public Health 2023; 11:1159348. [PMID: 37457253 PMCID: PMC10344449 DOI: 10.3389/fpubh.2023.1159348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 06/08/2023] [Indexed: 07/18/2023] Open
Abstract
Background Noise energy has been well-established to increase the risk of occupational noise-induced hearing loss (NIHL). However, the role of noise temporal structure (expressed by kurtosis) or its combination with energy metrics (e.g., kurtosis-adjusted cumulative noise exposure, adj-CNE) in occupational NIHL was still unclear. Methods A cross-sectional survey of 867 Chinese workers, including 678 metal manufacturing workers and 189 workers exposed to Gaussian noise, was conducted. Noise energy metrics, including LAeq,8h and CNE, kurtosis (β), and adj-CNE were used to quantify noise exposure levels. Noise-induced permanent threshold shift at frequencies 3, 4, and 6 kHz (NIPTS346) and the prevalence of high-frequency NIHL (HFNIHL%) were calculated for each participant. The dose-response relationship between kurtosis or adj-CNE and occupational NIHL was observed. Results Among 867 workers, different types of work had specific and independent noise energy and kurtosis values (p > 0.05). HFNIHL% increased with an increase in exposure duration (ED), LAeq,8h, CNE, or kurtosis (p < 0.01), and there were strong linear relationships between HFNIHL% and ED (coefficient of determination [R2] = 0.963), CNE (R2 = 0.976), or kurtosis (R2 = 0.938, when CNE < 100 dB(A)∙year). The "V" shape notching extent in NIPTS became deeper with increasing kurtosis when CNE < 100 dB(A)∙year and reached the notching bottom at the frequency of 4 or 6 kHz. The workers exposed to complex noise (β ≥ 10) had a higher risk of NIHL than those exposed to Gaussian noise (β < 10) at the frequencies of 3, 4, 6, and 8 kHz (OR > 2, p < 0.01). Moreover, HFNIHL% increased with adj-CNE (p < 0.001). There were strong linear relationships between NIHL and adj-CNE or CNE when β ≥ 10 (R2adj-CNE > R2CNE). After CNE was adjusted by kurtosis, average differences in NIPTS346 or HFNIHL% between the complex and Gaussian noise group were significantly reduced (p < 0.05). Conclusion Kurtosis was a key factor influencing occupational NIHL among metal manufacturing workers, and its combination with energy metrics could assess the risk of NIHL more effectively than CNE alone.
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Affiliation(s)
- Shuangyan Liu
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hua Zou
- Institute of Occupational Health and Radiation Protection, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, China
| | - Song Lei
- Ningbo Center for Disease Control and Prevention, Ningbo, Zhejiang, China
| | - Jiarui Xin
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Peiyi Qian
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Yun Liu
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Yingqi Chen
- School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Kuai Yu
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Meibian Zhang
- Chinese Center for Disease Control and Prevention, Beijing, China
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Smith-Cortinez N, Tan AK, Stokroos RJ, Versnel H, Straatman LV. Regeneration of Hair Cells from Endogenous Otic Progenitors in the Adult Mammalian Cochlea: Understanding Its Origins and Future Directions. Int J Mol Sci 2023; 24:ijms24097840. [PMID: 37175547 PMCID: PMC10177935 DOI: 10.3390/ijms24097840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Sensorineural hearing loss is caused by damage to sensory hair cells and/or spiral ganglion neurons. In non-mammalian species, hair cell regeneration after damage is observed, even in adulthood. Although the neonatal mammalian cochlea carries regenerative potential, the adult cochlea cannot regenerate lost hair cells. The survival of supporting cells with regenerative potential after cochlear trauma in adults is promising for promoting hair cell regeneration through therapeutic approaches. Targeting these cells by manipulating key signaling pathways that control mammalian cochlear development and non-mammalian hair cell regeneration could lead to regeneration of hair cells in the mammalian cochlea. This review discusses the pathways involved in the development of the cochlea and the impact that trauma has on the regenerative capacity of the endogenous progenitor cells. Furthermore, it discusses the effects of manipulating key signaling pathways targeting supporting cells with progenitor potential to promote hair cell regeneration and translates these findings to the human situation. To improve hearing recovery after hearing loss in adults, we propose a combined approach targeting (1) the endogenous progenitor cells by manipulating signaling pathways (Wnt, Notch, Shh, FGF and BMP/TGFβ signaling pathways), (2) by manipulating epigenetic control, and (3) by applying neurotrophic treatments to promote reinnervation.
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Affiliation(s)
- Natalia Smith-Cortinez
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - A Katherine Tan
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Robert J Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Huib Versnel
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
| | - Louise V Straatman
- Department of Otorhinolaryngology and Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
- UMC Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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Kirk JR, Smyth D, Dueck WF. A new paradigm of hearing loss and preservation with cochlear implants: Learnings from fundamental studies and clinical research. Hear Res 2023; 433:108769. [PMID: 37120894 DOI: 10.1016/j.heares.2023.108769] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 02/18/2023] [Accepted: 04/15/2023] [Indexed: 05/02/2023]
Abstract
In 2010 Cochlear initiated a coordinated preclinical research program to identify the factors and underlying mechanisms of acoustic hearing loss following cochlear implantation and device use. At its inception the program was structured around several major hypotheses implicated in the loss of acoustic hearing. The understanding of causes evolved over the course of the program, leading to an increased appreciation of the role of the biological response in post-implant hearing loss. A systematic approach was developed which mapped the cochlear implant journey along a timeline that considers all events in an individual's hearing history. By evaluating the available data in this context, rather than by discrete hypothesis testing, causative and associated factors may be more readily detected. This approach presents opportunities for more effective research management and may aid in identifying new prospects for intervention. Many of the outcomes of the research program apply beyond preservation of acoustic hearing to factors important to overall cochlear health and considerations for future therapies.
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Affiliation(s)
- Jonathon R Kirk
- Cochlear Limited, 1 University Avenue, Macquarie University, NSW 2109, Australia.
| | - Daniel Smyth
- Cochlear Limited, 1 University Avenue, Macquarie University, NSW 2109, Australia
| | - Wolfram F Dueck
- Cochlear Limited, 1 University Avenue, Macquarie University, NSW 2109, Australia
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Manickam V, Gawande DY, Stothert AR, Clayman AC, Batalkina L, Warchol ME, Ohlemiller KK, Kaur T. Macrophages Promote Repair of Inner Hair Cell Ribbon Synapses following Noise-Induced Cochlear Synaptopathy. J Neurosci 2023; 43:2075-2089. [PMID: 36810227 PMCID: PMC10039750 DOI: 10.1523/jneurosci.1273-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 02/23/2023] Open
Abstract
Resident cochlear macrophages rapidly migrate into the inner hair cell synaptic region and directly contact the damaged synaptic connections after noise-induced synaptopathy. Eventually, such damaged synapses are spontaneously repaired, but the precise role of macrophages in synaptic degeneration and repair remains unknown. To address this, cochlear macrophages were eliminated using colony stimulating factor 1 receptor (CSF1R) inhibitor, PLX5622. Sustained treatment with PLX5622 in CX3CR1 GFP/+ mice of both sexes led to robust elimination of resident macrophages (∼94%) without significant adverse effects on peripheral leukocytes, cochlear function, and structure. At 1 day (d) post noise exposure of 93 or 90 dB SPL for 2 hours, the degree of hearing loss and synapse loss were comparable in the presence and absence of macrophages. At 30 d after exposure, damaged synapses appeared repaired in the presence of macrophages. However, in the absence of macrophages, such synaptic repair was significantly reduced. Remarkably, on cessation of PLX5622 treatment, macrophages repopulated the cochlea, leading to enhanced synaptic repair. Elevated auditory brainstem response thresholds and reduced auditory brainstem response Peak 1 amplitudes showed limited recovery in the absence of macrophages but recovered similarly with resident and repopulated macrophages. Cochlear neuron loss was augmented in the absence of macrophages but showed preservation with resident and repopulated macrophages after noise exposure. While the central auditory effects of PLX5622 treatment and microglia depletion remain to be investigated, these data demonstrate that macrophages do not affect synaptic degeneration but are necessary and sufficient to restore cochlear synapses and function after noise-induced synaptopathy.SIGNIFICANCE STATEMENT The synaptic connections between cochlear inner hair cells and spiral ganglion neurons can be lost because of noise over exposure or biological aging. This loss may represent the most common causes of sensorineural hearing loss also known as hidden hearing loss. Synaptic loss results in degradation of auditory information, leading to difficulty in listening in noisy environments and other auditory perceptual disorders. We demonstrate that resident macrophages of the cochlea are necessary and sufficient to restore synapses and function following synaptopathic noise exposure. Our work reveals a novel role for innate-immune cells, such as macrophages in synaptic repair, that could be harnessed to regenerate lost ribbon synapses in noise- or age-linked cochlear synaptopathy, hidden hearing loss, and associated perceptual anomalies.
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Affiliation(s)
- Vijayprakash Manickam
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Dinesh Y Gawande
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Andrew R Stothert
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Anna C Clayman
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Lyudmila Batalkina
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
| | - Mark E Warchol
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Kevin K Ohlemiller
- Department of Otolaryngology, School of Medicine, Washington University, St. Louis, Missouri 63110
| | - Tejbeer Kaur
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, Nebraska 68178
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Natarajan N, Batts S, Stankovic KM. Noise-Induced Hearing Loss. J Clin Med 2023; 12:2347. [PMID: 36983347 PMCID: PMC10059082 DOI: 10.3390/jcm12062347] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/10/2023] [Accepted: 03/14/2023] [Indexed: 03/22/2023] Open
Abstract
Noise-induced hearing loss (NIHL) is the second most common cause of sensorineural hearing loss, after age-related hearing loss, and affects approximately 5% of the world's population. NIHL is associated with substantial physical, mental, social, and economic impacts at the patient and societal levels. Stress and social isolation in patients' workplace and personal lives contribute to quality-of-life decrements which may often go undetected. The pathophysiology of NIHL is multifactorial and complex, encompassing genetic and environmental factors with substantial occupational contributions. The diagnosis and screening of NIHL are conducted by reviewing a patient's history of noise exposure, audiograms, speech-in-noise test results, and measurements of distortion product otoacoustic emissions and auditory brainstem response. Essential aspects of decreasing the burden of NIHL are prevention and early detection, such as implementation of educational and screening programs in routine primary care and specialty clinics. Additionally, current research on the pharmacological treatment of NIHL includes anti-inflammatory, antioxidant, anti-excitatory, and anti-apoptotic agents. Although there have been substantial advances in understanding the pathophysiology of NIHL, there remain low levels of evidence for effective pharmacotherapeutic interventions. Future directions should include personalized prevention and targeted treatment strategies based on a holistic view of an individual's occupation, genetics, and pathology.
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Affiliation(s)
- Nirvikalpa Natarajan
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Shelley Batts
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Konstantina M. Stankovic
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
- Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
- Wu Tsai Neuroscience Institute, Stanford University, Stanford, CA 94305, USA
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Reynolds A, Bielefeld EC. Music as a unique source of noise-induced hearing loss. Hear Res 2023; 430:108706. [PMID: 36736160 DOI: 10.1016/j.heares.2023.108706] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 01/06/2023] [Accepted: 01/22/2023] [Indexed: 01/25/2023]
Abstract
Music is among the most important artistic, cultural, and entertainment modalities in any society. With the proliferation of music genres and the technological advances that allow people to consume music in any location and at any time, music over-exposure has become a significant public health issue. Music-induced hearing loss has a great deal in common with noise-induced hearing loss. However, there are important differences that make music a unique insult to the auditory system and a unique threat to public health. Its unique properties also make it a potentially valuable asset in sound conditioning paradigms. This review discusses hearing loss from noise and music, comparing and contrasting the two. Recent research on music-induced hearing loss is reviewed, followed by discussion of the differences in music-induced hearing loss between performers and consumers. The review concludes with a discussion of the potential of music as a sound conditioning stimulus to protect against acquired hearing loss.
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Affiliation(s)
- Alison Reynolds
- Department of Speech and Hearing Science, The Ohio State University, 110 Pressey Hall, 1070 Carmack Road, Columbus, OH 43210, USA
| | - Eric C Bielefeld
- Department of Speech and Hearing Science, The Ohio State University, 110 Pressey Hall, 1070 Carmack Road, Columbus, OH 43210, USA.
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Association of Clinical Aspects and Genetic Variants with the Severity of Cisplatin-Induced Ototoxicity in Head and Neck Squamous Cell Carcinoma: A Prospective Cohort Study. Cancers (Basel) 2023; 15:cancers15061759. [PMID: 36980643 PMCID: PMC10046479 DOI: 10.3390/cancers15061759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/01/2023] [Accepted: 03/07/2023] [Indexed: 03/16/2023] Open
Abstract
Background: Cisplatin (CDDP) is a major ototoxic chemotherapy agent for head and neck squamous cell carcinoma (HNSCC) treatment. Clinicopathological features and genotypes encode different stages of CDDP metabolism, as their coexistence may influence the prevalence and severity of hearing loss. Methods: HNSCC patients under CDDP chemoradiation were prospectively provided with baseline and post-treatment audiometry. Clinicopathological features and genetic variants encoding glutathione S-transferases (GSTT1, GSTM1, GSTP1), nucleotide excision repair (XPC, XPD, XPF, ERCC1), mismatch repair (MLH1, MSH2, MSH3, EXO1), and apoptosis (P53, CASP8, CASP9, CASP3, FAS, FASL)-related proteins were analyzed regarding ototoxicity. Results: Eighty-nine patients were included, with a cumulative CDDP dose of 260 mg/m2. Moderate/severe ototoxicity occurred in 26 (29%) patients, particularly related to hearing loss at frequencies over 3000 Hertz. Race, body-mass index, and cumulative CDDP were independent risk factors. Patients with specific isolated and combined genotypes of GSTM1, GSTP1 c.313A>G, XPC c.2815A>C, XPD c.934G>A, EXO1 c.1762G>A, MSH3 c.3133A>G, FASL c.-844A>T, and P53 c.215G>C SNVs had up to 32.22 higher odds of presenting moderate/severe ototoxicity. Conclusions: Our data present, for the first time, the association of combined inherited nucleotide variants involved in CDDP efflux, DNA repair, and apoptosis with ototoxicity, which could be potential predictors in future clinical and genomic models.
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Adegboye O. The Echoes of Noise: Residential Exposure to Traffic and Risk of Tinnitus. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:34001. [PMID: 36917477 PMCID: PMC10013688 DOI: 10.1289/ehp12762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
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Yeşiltepe A, Karadağ G. The effect of occupational training provided to workers in a glass factory on their use of ear protectors. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2023; 29:236-242. [PMID: 35098896 DOI: 10.1080/10803548.2022.2035989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Objectives. This study aimed to determine the effect of occupational training applied to workers working in noisy parts of a glass factory on the use of ear protectors. Methods. The study was a semi-experimental pre-test and post-test design. It was carried out with 45 workers determined by purposeful sampling and working in a glass production factory who accepted to participate in the study. The data were collected with an information form and noise-related symptom chart, hearing health information questionnaire and observation. In the analysis of the study data, the number/percentage, χ2 test, Cohen κ test and analysis of variance were used. Results. It was determined that workers pre training did not use ear protectors (100%) and there were some noise-related health complaints. There was an increase in using ear protectors (57.8%) and a decrease in their health complaints post training. It was also found that the workers' pre-training hearing health information questionnaire mean score was 11.46 ± 3.20, and post training was 13.77 ± 3.42 in the first month and 15.77 ± 2.88 in the fourth month. Conclusions. Occupational training provided to the workers increased the workers' awareness level and their rate of wearing ear protectors, and health problems caused by work-related noise started to recover.
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Affiliation(s)
| | - Gülendam Karadağ
- Department of Public Health Nursing, Dokuz Eylül University, Turkey
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Chen SM, Fan YT, Martinez RM, Chen C. Noise-induced hearing loss profile among Taiwan Airforce on duty pilots. Am J Otolaryngol 2023; 44:103802. [PMID: 36871421 DOI: 10.1016/j.amjoto.2023.103802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 02/01/2023] [Accepted: 02/19/2023] [Indexed: 03/02/2023]
Abstract
PURPOSE Noise-induced hearing loss (NIHL) often results in impaired functional hearing and accidental injuries; thus, reducing military performance and endangering flight safety. While a few studies addressing laterality (left-right ear differences) and NIHL incidence between fixed-winged (jet-fighter) and rotary-wing (helicopter) aircrafts yielded inconsistent results, little is known about the NIHL profile among different types of jet-fighter pilots. This study aims to conduct a fine-grained examination of NIHL among Airforce jet pilots, with planned comparisons of laterality and aircraft type, along with the goal to compare the sensitivity of different hearing indices in predicting military pilot NIHL. MATERIALS AND METHODS This cross-sectional study utilizes the health and hearing data of 1025 Taiwanese Air Force Military pilots from the 2019 Taiwanese physical examination database to assess the changes in their hearing thresholds, and evaluate their risk for NIHL. RESULTS Our results showed that, among available military aircraft types, the trainer aircraft and M2000-5 jet-fighter had the highest risk of NIHL, in addition to a left ear inferiority found in the overall population of military pilots. Among the three hearing indices used in this study -the International Organization for Standardization (ISO) three-point hearing index, the Occupational Safety and Health Administration (OSHA) three-point hearing index, and the American Academy of Otolaryngology-Head and Neck Surgery's (AAO-HNS) high-frequency three-point hearing index-, the OSHA the AAO-HNS were the most sensitive. CONCLUSION Our results suggest a better noise protection for trainer and M2000-5 pilots, especially for the left ear, is warranted.
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Affiliation(s)
- Shih-Ming Chen
- Department of Otolaryngology, Tri-Serive General Hospital Songshan Branch, National Defense Medical Center, Taipei 114, Taiwan; Graduate Institute of Injury Prevention and Control, College of Public Health, Taipei Medical University, Taipei 110, Taiwan; Department of Otolaryngology, Taoyuan Armed Forces General Hospital, Taoyuan 325, Taiwan; Department of Biomedical Sciences and Engineering, National Central University, Taoyuan 320, Taiwan
| | - Yang-Teng Fan
- Graduate Institute of Medicine, Yuan Ze University, Taoyuan 320, Taiwan
| | - Róger Marcelo Martinez
- Graduate Institute of Injury Prevention and Control, College of Public Health, Taipei Medical University, Taipei 110, Taiwan; School of Psychological Sciences, National Autonomous University of Honduras, Tegucigalpa, Honduras.
| | - Chenyi Chen
- Graduate Institute of Injury Prevention and Control, College of Public Health, Taipei Medical University, Taipei 110, Taiwan; Brain and Consciousness Research Center, Shuang-Ho Hospital, Taipei Medical University, New Taipei City 234, Taiwan; Graduate Institute of Mind, Brain and Consciousness, College of Humanities and Social Sciences, Taipei Medical University, Taipei 110, Taiwan; Psychiatric Research Center, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan.
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Nyarubeli IP, Tungu AM, Pallesen S, Moen BE, Mamuya SHD. Development and initial validation of questionnaire on predictors for the use of hearing protection devices among noise exposed manufacturing workers in Tanzania: A methodological study. Front Public Health 2023; 11:1102343. [PMID: 36844814 PMCID: PMC9947289 DOI: 10.3389/fpubh.2023.1102343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/23/2023] [Indexed: 02/11/2023] Open
Abstract
Introduction The use of hearing protection devices (HPDs) has been an intervention of choice in many workplaces such as in the construction industry for quite some time due to impractical effects of engineering and administrative interventions. Questionnaires for assessment for HPDs use among construction workers have been developed and validated in developed countries. However, there is limited knowledge of the same, among manufacturing workers in developing countries that are assumed to have a different culture, work organizations and production processes. Methods We conducted a stepwise methodological study to develop a questionnaire to predict the use of HPDs among noise exposed workers in manufacturing factories in Tanzania. The questionnaire included 24 items and was developed through rigorous and systematic procedures involving three steps; (i) item formulation that involved two experts, (ii) expert content review and item rating that involving eight experts with vast experience in the field, and (iii) a field pre-test that involved 30 randomly selected workers from a factory with similar characteristics as a planned study site. A modified Pender's Health Promotion Model was adopted in the questionnaire development. We analyzed the questionnaire in terms of content validity and item reliability. Results The 24 items were categorized into seven domains i.e., perceived self-efficacy, perceived susceptibility, perceived benefits, perceived barriers, interpersonal influences, situational influences and safety climate. The score for content validity for each item was satisfactory as the content validity index ranged between 0.75 to 1.00 for clarity, relevance, and essentiality criteria. Similarly, the scores for the content validity ratio (for all items) were 0.93, 0.88 and 0.93 for clarity, relevance, and essentiality, respectively. In addition, the overall value for Cronbach's alpha was 0.92 with domain coefficients: perceived self-efficacy 0.75; perceived susceptibility 0.74; perceived benefits 0.86; perceived barriers 0.82; interpersonal influences 0.79; situational influences; 0.70; and safety climate 0.79. The mean inter-item correlation was 0.49 suggesting good internal consistency. Discussion and conclusion The developed and preliminary validated questionnaire can be used to predict the HPDs use among noise exposed manufacturing factory workers. Future surveys using this questionnaires warranted for further validation of the scale developed.
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Affiliation(s)
- Israel Paul Nyarubeli
- Department of Environmental and Occupational Health, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania,Research Group for Occupational and Environmental Medicine, Department of Global Public and Primary Care, University of Bergen, Bergen, Norway
| | - Alexander Mtemi Tungu
- Research Group for Occupational and Environmental Medicine, Department of Global Public and Primary Care, University of Bergen, Bergen, Norway,Department of Physiology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Ståle Pallesen
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Bente Elisabeth Moen
- Centre for International Health, Department of Global Public and Primary Care, University of Bergen, Bergen, Norway,*Correspondence: Bente Elisabeth Moen ✉
| | - Simon Henry David Mamuya
- Department of Environmental and Occupational Health, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
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Shrestha S, Baral B, Dawadi A, Sherpa P, Regmi D. Noise-induced Hearing Loss among Patients Requiring Pure Tone Audiometry Evaluation in a Tertiary Care Centre: A Descriptive Cross-sectional Study. JNMA J Nepal Med Assoc 2023; 61:98-101. [PMID: 37203985 PMCID: PMC10088996 DOI: 10.31729/jnma.8008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Indexed: 08/17/2023] Open
Abstract
INTRODUCTION Noise-induced hearing loss is a type of sensorineural hearing loss caused by long-term exposure to loud noise. This study provides insight into hearing loss problems the general population faces. The study aimed to find out the prevalence of noise-induced hearing loss among patients needing pure tone audiometry evaluation in a tertiary care centre. METHODS A descriptive cross-sectional study was conducted from 1 January 2021 to 30 July 2021 among patients requiring pure tone audiometry evaluation in the outpatient Department of Otorhinolaryngology in a tertiary care centre. The study was conducted after ethical approval from Institutional Review Committee (Reference number: 2812202001). Pure tone audiometry was used to diagnose noise-induced hearing loss. Convenience sampling was done. Point estimate and 95% Confidence Interval were calculated. RESULTS Out of 690 patients, 14 (2.02%) (0.97-3.06, 95% Confidence Interval) were diagnosed with noise-induced hearing loss. CONCLUSIONS The prevalence of noise-induced hearing loss among patients requiring pure tone audiometry evaluation was similar to other studies conducted in similar settings. KEYWORDS audiometry; noise-induced hearing loss; tinnitus.
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Affiliation(s)
- Sangita Shrestha
- Department of Otorhinolaryngology, Kathmandu Medical College and Teaching Hospital, Sinamangal, Kathmandu, Nepal
| | - Biraj Baral
- Kathmanau Medical College and Teaching Hospital, Sinamangal, Kathmandu, Nepal
| | - Aakriti Dawadi
- Maharajgunj Medical Campus, Maharajgunj, Kathmandu, Nepal
| | - Pema Sherpa
- Department of Otorhinolaryngology, Kathmandu Medical College and Teaching Hospital, Sinamangal, Kathmandu, Nepal
| | - Deepak Regmi
- Department of Otorhinolaryngology, Kathmandu Medical College and Teaching Hospital, Sinamangal, Kathmandu, Nepal
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Chen XM, Liu YH, Ji SF, Xue XM, Wang LL, Zhang M, Chang YM, Wang XC. Protective effect of ginsenoside Rd on military aviation noise-induced cochlear hair cell damage in guinea pigs. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:23965-23981. [PMID: 36331733 DOI: 10.1007/s11356-022-23504-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
Noise pollution has become one of the important social hazards that endanger the auditory system of residents, causing noise-induced hearing loss (NIHL). Oxidative stress has a significant role in the pathogenesis of NIHL, in which the silent information regulator 1(SIRT1)/proliferator-activated receptor-gamma coactivator 1α (PGC-1α) signaling pathway is closely engaged. Ginsenoside Rd (GSRd), a main monomer extract from ginseng plants, has been confirmed to suppress oxidative stress. Therefore, the hypothesis that GSRd may attenuate noise-induced cochlear hair cell loss seemed promising. Forty-eight male guinea pigs were randomly divided into four groups: control, noise exposure, GSRd treatment (30 mg/kg Rd for 10d + noise), and experimental control (30 mg/kg glycerol + noise). The experimental groups received military helicopter noise exposure at 115 dB (A) for 4 h daily for five consecutive days. Hair cell damage was evaluated by using inner ear basilar membrane preparation and scanning electron microscopy. Terminal dUTP nick end labeling (TUNEL) and immunofluorescence staining were conducted. Changes in the SIRT1/PGC-1α signaling pathway and other apoptosis-related markers in the cochleae, as well as oxidative stress parameters, were used as readouts. Loss of outer hair cells, more disordered cilia, prominent apoptosis, and elevated free radical levels were observed in the experimental groups. GSRd treatment markedly mitigated hearing threshold shifts, ameliorated outer hair cell loss and lodging or loss of cilia, and improved apoptosis through decreasing Bcl-2 associated X protein (Bax) expression and increasing Bcl-2 expression. In addition, GSRd alleviated the noise-induced cochlear redox injury by upregulating superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels, decreasing malondialdehyde (MDA) levels, and enhancing the activity of SIRT1 and PGC-1α messenger ribonucleic acid (mRNA) and protein expression. In conclusion, GSRd can improve structural and oxidative damage to the cochleae caused by noise. The underlying mechanisms may be associated with the SIRT1/PGC-1α signaling pathway.
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Affiliation(s)
- Xue-Min Chen
- Department of Aerospace Hygiene, School of Aerospace Medicine, Air Force Medical University, Xi'an, China
- Medical School of Chinese PLA, Beijing, China
- Senior Department of Otolaryngology-Head & Neck Surgery, Chinese PLA General Hospital; National Clinical Research Center for Otolaryngologic Diseases; State Key Lab of Hearing Science, Ministry of Education; Beijing Key Lab of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Yu-Hui Liu
- Center of Clinical Aerospace Medicine, School of Aerospace Medicine, Key Laboratory of Aerospace Medicine of Ministry of Education, Air Force Medical University, Xi'an, China
- Department of Aviation Medicine, The First Affiliated Hospital of Air Force Military Medical University, Xi'an, China
- Air Force Health Care Center for Special Services, Hangzhou, China
| | - Shuai-Fei Ji
- Medical School of Chinese PLA, Beijing, China
- Research Center for Tissue Repair and Regeneration Affiliated to the Medical Innovation Research Department and 4th Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Xin-Miao Xue
- Medical School of Chinese PLA, Beijing, China
- Senior Department of Otolaryngology-Head & Neck Surgery, Chinese PLA General Hospital; National Clinical Research Center for Otolaryngologic Diseases; State Key Lab of Hearing Science, Ministry of Education; Beijing Key Lab of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Lin-Lin Wang
- Senior Department of Otolaryngology-Head & Neck Surgery, Chinese PLA General Hospital; National Clinical Research Center for Otolaryngologic Diseases; State Key Lab of Hearing Science, Ministry of Education; Beijing Key Lab of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Min Zhang
- Center of Clinical Aerospace Medicine, School of Aerospace Medicine, Key Laboratory of Aerospace Medicine of Ministry of Education, Air Force Medical University, Xi'an, China
- Department of Aviation Medicine, The First Affiliated Hospital of Air Force Military Medical University, Xi'an, China
| | - Yao-Ming Chang
- Department of Aerospace Hygiene, School of Aerospace Medicine, Air Force Medical University, Xi'an, China
| | - Xiao-Cheng Wang
- Center of Clinical Aerospace Medicine, School of Aerospace Medicine, Key Laboratory of Aerospace Medicine of Ministry of Education, Air Force Medical University, Xi'an, China.
- Department of Aviation Medicine, The First Affiliated Hospital of Air Force Military Medical University, Xi'an, China.
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Yakkanti RR, Sedani AB, Syros A, Aiyer AA, D’Apuzzo MR, Hernandez VH. Prevalence and Spectrum of Occupational Injury Among Orthopaedic Surgeons: A Cross-Sectional Study. JB JS Open Access 2023; 8:JBJSOA-D-22-00083. [PMID: 36733707 PMCID: PMC9886518 DOI: 10.2106/jbjs.oa.22.00083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Orthopaedic surgeons are at increased risk for many occupational hazards, both physical and mental. The aim of this study was to evaluate a wide range of work-related injuries among orthopaedic surgeons in the United States. Methods An electronic survey was developed to assess both physical and mental occupational hazards among orthopaedic surgeons. Descriptive statistics were analyzed for all survey items and compared using chi-square and paired t tests, as appropriate. Results The 1,645 responding orthopaedic surgeons (7% response rate) reported a total of 2,702 work-related musculoskeletal injuries, 17.9% of which required surgical treatment. Of the 61 who filed a disability claim, only 66% returned to work and 34% retired early. Additionally, 17.4% of respondents reported having been diagnosed with cancer since starting practice, and 93.8% reported experiencing a finger stick at some point in their career. Over one-half (55.8%) had experienced feelings of psychological distress since beginning practice, and nearly two-thirds (64.4%) reported burnout from work. Conclusions This study captured a spectrum of occupational injuries that pose longitudinal risks to an orthopaedic surgeon's physical and mental well-being. Our hope is that this analysis of occupational hazards will help to raise awareness among the orthopaedic and medical communities and lead to efforts to reduce these risks. Level of Evidence Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Ramakanth R. Yakkanti
- Department of Orthopaedic Surgery, University of Miami/Jackson Health Systems, Miami, Florida
| | - Anil B. Sedani
- Department of Orthopaedic Surgery, University of Miami/Jackson Health Systems, Miami, Florida
| | - Alina Syros
- Miller School of Medicine, University of Miami, Miami, Florida,Email for corresponding author:
| | - Amiethab A. Aiyer
- Department of Orthopaedic Surgery, Johns Hopkins Medicine, Baltimore, Maryland
| | - Michele R. D’Apuzzo
- Department of Orthopaedic Surgery, University of Miami/Jackson Health Systems, Miami, Florida
| | - Victor H. Hernandez
- Department of Orthopaedic Surgery, University of Miami/Jackson Health Systems, Miami, Florida
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Li P, Li S, Wang L, Li H, Wang Y, Liu H, Wang X, Zhu X, Liu Z, Ye F, Zhang Y. Mitochondrial dysfunction in hearing loss: Oxidative stress, autophagy and NLRP3 inflammasome. Front Cell Dev Biol 2023; 11:1119773. [PMID: 36891515 PMCID: PMC9986271 DOI: 10.3389/fcell.2023.1119773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 02/07/2023] [Indexed: 02/22/2023] Open
Abstract
Sensorineural deafness becomes an inevitable worldwide healthy problem, yet the current curative therapy is limited. Emerging evidences demonstrate mitochondrial dysfunction plays a vital role of in the pathogenesis of deafness. Reactive oxygen species (ROS)-induced mitochondrial dysfunction combined with NLRP3 inflammasome activation is involved in cochlear damage. Autophagy not only clears up undesired proteins and damaged mitochondria (mitophagy), but also eliminate excessive ROS. Appropriate enhancement of autophagy can reduce oxidative stress, inhibit cell apoptosis, and protect auditory cells. In addition, we further discuss the interplays linking ROS generation, NLRP3 inflammasome activation, and autophagy underlying the pathogenesis of deafness, including ototoxic drugs-, noise- and aging-related hearing loss.
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Affiliation(s)
- Peipei Li
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Province Research Center for Kidney Disease, Zhengzhou, China
| | - Shen Li
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Le Wang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Hongmin Li
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yang Wang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Hongbing Liu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xin Wang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiaodan Zhu
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zhangsuo Liu
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Province Research Center for Kidney Disease, Zhengzhou, China
| | - Fanglei Ye
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yuan Zhang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Özcan E, Broekmeulen CLH, Luck ZA, van Velzen M, Stappers PJ, Edworthy JR. Acoustic Biotopes, Listeners and Sound-Induced Action: A Case Study of Operating Rooms. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:16674. [PMID: 36554556 PMCID: PMC9779544 DOI: 10.3390/ijerph192416674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
As socio-technological environments shape and direct listener behaviour, an ecological account is needed that encompasses listening in complexity (i.e., multiple listeners, multiple sounds and their sources, and multiple sound-induced actions that ensure the success of a mission). In this study, we explored sound-induced action under the framework of "acoustic biotopes" (a notion of ecological acoustics by Smolders, Aertsen, and Johanessma, 1979 and 1982) in a specific socio-technological environment, i.e., the context of an orthopaedic operating room. Our approach is based on literature research into the topics of environmental psychology and auditory perception and action and in situ observations in healthcare with field recordings, participatory observations, and interviews on the spot. The results suggest a human-centered definition of sound-induced action in acoustic biotopes: Acoustic biotope is an active and shared sound environment with entangled interactions and sound-induced actions taking place in a specific space that has a critical function. Listening in highly functional environments is an individual experience and is influenced by hearing function, physical position and role in an environment, and the task at hand. There is a range of active and passive sound listeners as a function of their attentive state and listeners as sound sources within the acoustic biotope. There are many different sound sources and sound locals in socio-technological environments and sounds have great potential to serve critical information to operators. Overall, our study provides a holistic, multi-layered and yet a listener-centric view on the organisation of complex spaces and the results can immediately be applicable for rethinking the acoustic environment for ORs for better listening and sound-induced action.
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Affiliation(s)
- Elif Özcan
- Critical Alarms Lab, Faculty of Industrial Design Engineering, Delft University of Technology, 2628 CE Delft, The Netherlands
| | - Cornelis L. H. Broekmeulen
- Critical Alarms Lab, Faculty of Industrial Design Engineering, Delft University of Technology, 2628 CE Delft, The Netherlands
| | - Zoe Alexandra Luck
- Critical Alarms Lab, Faculty of Industrial Design Engineering, Delft University of Technology, 2628 CE Delft, The Netherlands
| | - Monique van Velzen
- Department of Anaesthesiology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Pieter Jan Stappers
- Department of Human-Centered Design, Faculty of Industrial Design Engineering, Delft University of Technology, 2628 CE Delft, The Netherlands
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Ma PW, Wang WL, Chen JW, Yuan H, Lu PH, Gao W, Ding XR, Lun YQ, Liang R, He ZH, Yang Q, Lu LJ. Treatment with the Ferroptosis Inhibitor Ferrostatin-1 Attenuates Noise-Induced Hearing Loss by Suppressing Ferroptosis and Apoptosis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3373828. [PMID: 36531206 PMCID: PMC9750774 DOI: 10.1155/2022/3373828] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/29/2022] [Accepted: 11/12/2022] [Indexed: 08/17/2023]
Abstract
Hair cell death induced by excessive reactive oxygen species (ROS) has been identified as the major pathogenesis of noise-induced hearing loss (NIHL). Recent studies have demonstrated that cisplatin- and neomycin-induced ototoxicity can be alleviated by ferroptosis inhibitors. However, whether ferroptosis inhibitors have a protective effect against NIHL remains unknown. We investigated the protective effect of the ferroptosis inhibitor ferrostatin-1 (Fer-1) on NIHL in vivo in CBA/J mice and investigated the protective effect of Fer-1 on tert-butyl hydroperoxide (TBHP)-induced hair cell damage in vitro in cochlear explants and HEI-OC1 cells. We observed ROS overload and lipid peroxidation, which led to outer hair cell (OHC) apoptosis and ferroptosis, in the mouse cochlea after noise exposure. The expression level of apoptosis-inducing factor mitochondria-associated 2 (AIFM2) was substantially increased following elevation of the expression of its upstream protein P53 after noise exposure. The ferroptosis inhibitor Fer-1was demonstrated to enter the inner ear after the systemic administration. Administration of Fer-1 significantly alleviated noise-induced auditory threshold elevation and reduced the loss of OHCs, inner hair cell (IHC) ribbon synapses, and auditory nerve fibers (ANFs) caused by noise. Mechanistically, Fer-1 significantly reduced noise- and TBHP-induced lipid peroxidation and iron accumulation in hair cells, alleviating ferroptosis in cochlear cells consequently. Furthermore, Fer-1 treatment decreased the levels of TfR1, P53, and AIFM2. These results suggest that Fer-1 exerted its protective effects by scavenging of ROS and inhibition of TfR1-mediated ferroptosis and P53-AIFM2 signaling pathway-mediated apoptosis. Our findings suggest that Fer-1 is a promising drug for treating NIHL because of its ability to inhibit noise-induced hair cell apoptosis and ferroptosis, opening new avenues for the treatment of NIHL.
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Affiliation(s)
- Peng-Wei Ma
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Wei-Long Wang
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Jia-Wei Chen
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Hao Yuan
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Pei-Heng Lu
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Wei Gao
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Xue-Rui Ding
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Yu-Qiang Lun
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Rui Liang
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Zu-Hong He
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qian Yang
- Department of Experimental Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
| | - Lian-Jun Lu
- Department of Otolaryngology Head and Neck Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, China
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Saraei M, Omidi R, Aminian O, Izadi N, Akbarpour S, Ebrahimi Meimand S. The Combined Effect of Noise and Solvent Exposure on Hearing Loss in the Tire Factory Workers. Indian J Otolaryngol Head Neck Surg 2022; 74:3887-3892. [PMID: 36742491 PMCID: PMC9895598 DOI: 10.1007/s12070-021-02697-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 06/20/2021] [Indexed: 02/07/2023] Open
Abstract
Noise and organic solvents are common in many industries and both of them affect hearing. In this study, we estimated the concurrent effect of them on hearing by evaluating the existence of notch in audiograms of workers. The number of 540 persons were enrolled in this study after eliminating workers who had the exclusion criteria. We divided them into 4 groups based on their exposure status; no exposure, exposure to noise, exposure to solvent, exposure to both of them. The presence of notch in left, right, or both ears were assessed through Coles model. The rates of notch presence in both ears in the groups of noise and organic solvents exposure, noise exposure only, solvents exposure only were 11.72, 4.49, 1.86 times higher than the control group and sole solvent exposure didn't affect hearing significantly. The same pattern was seen for notch presence in left or right ear and the solvent-noise exposure group had the highest rate of notch presence. This study aims to show the synergic effect of noise and organic solvents exposure on hearing loss. Hence, we recommend implementing a hearing protection program and a higher frequency of audiological assessments in the industries involved with concurrent exposure to noise and organic solvents.
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Affiliation(s)
- Maryam Saraei
- Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran, Iran
| | - Roya Omidi
- Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran, Iran
| | - Omid Aminian
- Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran, Iran
| | - Nazanin Izadi
- Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran, Iran
| | - Samaneh Akbarpour
- Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Singh K, Gude A, Kour A, Guthikonda MR, Mishra AK, Gupta A. A Prospective Study to Elucidate the Efficacy of 4 Oral Prednisolone Regimens in Acute Acoustic Trauma. Indian J Otolaryngol Head Neck Surg 2022; 74:3692-3699. [PMID: 36742739 PMCID: PMC9895518 DOI: 10.1007/s12070-021-02437-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/02/2021] [Indexed: 02/07/2023] Open
Abstract
Noise induced hearing loss affects around 5% of the population and acoustic trauma to military personnel accounts for 30% of all injuries inflicted during active service. Initial treatment for acoustic trauma involves administration of steroids, however there are no studies regarding oral steroid regimens for best outcomes. Comparing and elucidating the benefits of four oral steroid regimens on hearing gain in patients with acute acoustic trauma. A prospective study of 4 different steroid regimens was done in 200 soldiers from July 2014 - July 2020. In the first group, oral Prednisolone 60 mg was administered for 6 days, in the second group for 8 days, in the third group for 10 days and in the fourth group for 12 days. Medication was tapered over the next 5 days in all the groups. Data analysed included demographics, Pure Tone Audiograms at admission and at 4 weeks, time of reporting to hospital, onset of treatment and type of treatment given. Multivariate linear regression model was done to consider the risk factors responsible for average hearing gain at all pure tones. Box-and-whisker plot, Mann-Whitney-Wilcoxon test, Kruskal Wallis test, Reciever Operating Characteristic curve were used to analyse the independent samples. p value of < 0.05 was considered statistically significant. Age, time of onset of prednisolone therapy and acoustic trauma due to blast or gunshot injury did not show correlation (R2 = 0.01, 0.01 and 0.35 respectively and p = 0.09, 0.71, 0.80 respectively). Prednisolone therapy, average initial hearing at pure tones were considered as factors responsible for hearing gain as they showed correlation (R2 = 0.22, and 0.34 respectively and p < 0.001 and < 0.01 respectively). Significant hearing gain was found in all groups. The hearing gain was statistically better in group 3 and 4 as compared to group 1 and 2. There was no statistically significant difference in hearing gain between groups 3 and 4. So there was no additional advantage of giving 60 mg oral prednisolone for more than 10 days. The best oral prednisolone regimen recommended is 60 mg/day for 10 days which is tapered over the next 5 days.
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Affiliation(s)
- Kamalpreet Singh
- Dept of Otorhinolaryngology-Head & Neck Surgery, Armed Forces Medical College, Pune, Maharashtra India 411040
| | - Aswini Gude
- Department of Pathology, Gayatri Institute of Health Care &Medical Technology, GVP Medical College, Maridi Valley, Marikavalasa, Visakhapatnam, Andhra Pradesh 530048 India
| | - Amrindarjeet Kour
- Medical Officer, Armed Forced Medical College, Pune, Maharashtra 411040 India
| | - Mohan Raghav Guthikonda
- Dept of Otorhinolaryngology- Head & Neck Surgery, 166 Military Hospital, Satwari Cantonment, Jammu and Kashmir, Jammu, 180003 India
| | - Awadhesh Kumar Mishra
- Dept of Otorhinolaryngology-Head & Neck Surgery, Army College of Medical Sciences &Base Hospital, Delhi Cantt, New Delhi, India
| | - Arun Gupta
- Dept of PSM, AFMC, Pune, Maharashtra India
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Ertugrul S, Soylemez E, Gurel T. Effectiveness of hearing protection apparatus in preventing noise induced vestibular loss. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2022; 32:2708-2717. [PMID: 34629003 DOI: 10.1080/09603123.2021.1987395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
Hearing protection apparatus (HPAs) are frequently used to prevent the detrimental effect of noise on the hearing system. However, it is not known exactly whether wearing HPAs in workers protects the vestibular system. This study aims to investigate the effectiveness of wearing HPAs in preventing vestibular loss caused by noise. Eighty-one workers exposed to chronic noise were divided into three groups according to their HPAs wearing status. Pure-tone audiometry test was used to evaluate the hearing. Caloric test and visual analogue scale were used to evaluate their vestibular systems. The pure-tone average of the workers who constantly wore HPAs was better than that of the other groups (p< 0.05). There was no difference between the groups in the vestibular tests (p > 0.05). This study demonstrated that HPAs do not protect the vestibular system but protect the hearing system in the inner ear from the harmful effects of noise.
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Affiliation(s)
- Süha Ertugrul
- Department of Otorhinolaryngology, Faculty of Medicine, Karabuk University, Karabuk, Turkey
| | - Emre Soylemez
- Department of Audiology, Karabuk University, Vocational School of Health Services, Karabuk, Turkey
| | - Tuğçe Gurel
- Gaziosmanpaşa Training and Research Hospital, İstanbul, Turkey
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Requena T, Keder A, zur Lage P, Albert JT, Jarman AP. A Drosophila model for Meniere's disease: Dystrobrevin is required for support cell function in hearing and proprioception. Front Cell Dev Biol 2022; 10:1015651. [PMID: 36438562 PMCID: PMC9688402 DOI: 10.3389/fcell.2022.1015651] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/27/2022] [Indexed: 08/04/2023] Open
Abstract
Meniere's disease (MD) is an inner ear disorder characterised by recurrent vertigo attacks associated with sensorineural hearing loss and tinnitus. Evidence from epidemiology and Whole Exome Sequencing (WES) suggests a genetic susceptibility involving multiple genes, including α-Dystrobrevin (DTNA). Here we investigate a Drosophila model. We show that mutation, or knockdown, of the DTNA orthologue in Drosophila, Dystrobrevin (Dyb), results in defective proprioception and impaired function of Johnston's Organ (JO), the fly's equivalent of the inner ear. Dyb and another component of the dystrophin-glycoprotein complex (DGC), Dystrophin (Dys), are expressed in support cells within JO. Their specific locations suggest that they form part of support cell contacts, thereby helping to maintain the integrity of the hemolymph-neuron diffusion barrier, which is equivalent to a blood-brain barrier. These results have important implications for the human condition, and notably, we note that DTNA is expressed in equivalent cells of the mammalian inner ear.
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Affiliation(s)
- T. Requena
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
- Division of Functional Genetics and Development, The Royal Dick School of Veterinary Sciences, The Roslin Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - A. Keder
- Ear Institute, University College London, London, United Kingdom
| | - P. zur Lage
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
| | - J. T. Albert
- Ear Institute, University College London, London, United Kingdom
| | - A. P. Jarman
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
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Paik CB, Pei M, Oghalai JS. Review of blast noise and the auditory system. Hear Res 2022; 425:108459. [PMID: 35181171 PMCID: PMC9357863 DOI: 10.1016/j.heares.2022.108459] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 02/03/2022] [Accepted: 02/07/2022] [Indexed: 11/22/2022]
Abstract
The auditory system is particularly vulnerable to blast injury due to the ear's role as a highly sensitive pressure transducer. Over the past several decades, studies have used a variety of animal models and experimental procedures to recreate blast-induced acoustic trauma. Given the developing nature of this field and our incomplete understanding of molecular mechanisms underlying blast-related auditory disturbances, an updated discussion about these studies is warranted. Here, we comprehensively review well-established blast-related auditory pathology including tympanic membrane perforation and hair cell loss. In addition, we discuss important mechanistic studies that aim to bridge gaps in our current understanding of the molecular and microstructural events underlying blast-induced cochlear, auditory nerve, brainstem, and central auditory system damage. Key findings from the recent literature include the association between endolymphatic hydrops and cochlear synaptic loss, blast-induced neuroinflammatory markers in the peripheral and central auditory system, and therapeutic approaches targeting biochemical markers of blast injury. We conclude that blast is an extreme form of noise exposure. Blast waves produce cochlear damage that appears similar to, but more extreme than, the standard noise exposure protocols used in auditory research. However, experimental variations in studies of blast-induced acoustic trauma make it challenging to compare and interpret data across studies.
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Affiliation(s)
- Connie B Paik
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA USA
| | - Michelle Pei
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA USA
| | - John S Oghalai
- Caruso Department of Otolaryngology-Head and Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, CA USA.
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Grinn SK, Le Prell CG. Evaluation of hidden hearing loss in normal-hearing firearm users. Front Neurosci 2022; 16:1005148. [PMID: 36389238 PMCID: PMC9644938 DOI: 10.3389/fnins.2022.1005148] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/07/2022] [Indexed: 04/05/2024] Open
Abstract
Some noise exposures resulting in temporary threshold shift (TTS) result in cochlear synaptopathy. The purpose of this retrospective study was to evaluate a human population that might be at risk for noise-induced cochlear synaptopathy (i.e., "hidden hearing loss"). Participants were firearm users who were (1) at-risk for prior audiometric noise-induced threshold shifts, given their history of firearm use, (2) likely to have experienced complete threshold recovery if any prior TTS had occurred, based on this study's normal-hearing inclusion criteria, and (3) not at-risk for significant age-related synaptopathic loss, based on this study's young-adult inclusion criteria. 70 participants (age 18-25 yr) were enrolled, including 33 firearm users experimental (EXP), and 37 non-firearm users control (CNTRL). All participants were required to exhibit audiometric thresholds ≤20 dB HL bilaterally, from 0.25 to 8 kHz. The study was designed to test the hypothesis that EXP participants would exhibit a reduced cochlear nerve response compared to CNTRL participants, despite normal-hearing sensitivity in both groups. No statistically significant group differences in auditory performance were detected between the CNTRL and EXP participants on standard audiom to etry, extended high-frequency audiometry, Words-in-Noise performance, distortion product otoacoustic emission, middle ear muscle reflex, or auditory brainstem response. Importantly, 91% of EXP participants reported that they wore hearing protection either "all the time" or "almost all the time" while using firearms. The data suggest that consistent use of hearing protection during firearm use can effectively protect cochlear and neural measures of auditory function, including suprathreshold responses. The current results do not exclude the possibility that neural pathology may be evident in firearm users with less consistent hearing protection use. However, firearm users with less consistent hearing protection use are also more likely to exhibit threshold elevation, among other cochlear deficits, thereby confounding the isolation of any potentially selective neural deficits. Taken together, it seems most likely that firearm users who consistently and correctly use hearing protection will exhibit preserved measures of cochlear and neural function, while firearm users who inconsistently and incorrectly use hearing protection are most likely to exhibit cochlear injury, rather than evidence of selective neural injury in the absence of cochlear injury.
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Affiliation(s)
- Sarah K. Grinn
- Department of Communication Sciences and Disorders, Central Michigan University, Mount Pleasant, MI, United States
| | - Colleen G. Le Prell
- Department of Speech, Language, and Hearing, University of Texas at Dallas, Dallas, TX, United States
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Effects of pyrroloquinoline quinone on noise-induced and age-related hearing loss in mice. Sci Rep 2022; 12:15911. [PMID: 36151123 PMCID: PMC9508078 DOI: 10.1038/s41598-022-19842-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 09/05/2022] [Indexed: 11/10/2022] Open
Abstract
We investigated whether the oxidoreductase cofactor pyrroloquinoline quinone (PQQ) prevents noise-induced and age-related hearing loss (NIHL and ARHL) in mice. To assess NIHL, 8 week-old mice with and without PQQ administration were exposed to noise for 4 h. PQQ was orally administered for one week before and after noise exposure and subcutaneously once before noise exposure. For ARHL evaluation, mice were given drinking water with or without PQQ starting at 2 months of age. In the NIHL model, PQQ-treated mice had auditory brainstem response (ABR) thresholds of significantly reduced elevation at 8 kHz, a significantly increased number of hair cells at the basal turn, and significantly better maintained synapses beneath the inner hair cells compared to controls. In the ARHL model, PQQ significantly attenuated the age-related increase in ABR thresholds at 8 and 32 kHz at 10 months of age compared to controls. In addition, the hair cells, spiral ganglion cells, ribbon synapses, stria vascularis and nerve fibers were all significantly better maintained in PQQ-treated animals compared to controls at 10 months of age. These physiological and histological results demonstrate that PQQ protects the auditory system from NIHL and ARHL in mice.
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