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Donald Henderson - One of the best experts on this subject based on the ideXlab platform.
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protection from impulse noise induced Hearing Loss with novel src protein tyrosine kinase inhibitors
Neuroscience Research, 2011Co-Authors: Eric C Bielefeld, David G Hangauer, Donald HendersonAbstract:Apoptosis is a significant mechanism of cochlear hair cell Loss from noise. Molecules that inhibit apoptotic intracellular signaling reduce cochlear damage and Hearing Loss from noise. The current study is an extension of a previous study of the protective value of Src-protein tyrosine kinase inhibitors against noise (Harris et al., 2005). The current study tested three Src-inhibitors: the indole-based KX1-141, the biaryl-based KX2-329, and the ATP-competitive KX2-328. Each of the three drugs was delivered into the chinchillas’ cochleae by allowing the solutions to diffuse across the round window membrane thirty minutes prior to exposure to impulse noise. Hearing thresholds were measured using auditory evoked responses from electrodes in the inferior colliculi. Ears treated with KX2-329 showed significantly lower threshold shifts and outer hair cell Losses than the control group. The cochleae treated with KX1-141 and KX2-328 did not show statistically significant protection from the impulse noise. The finding of protection with KX2-329 demonstrates that a biaryl-based Src inhibitor has protective capacity against Noise-Induced Hearing Loss that is as good as that demonstrated by KX1-004, a Src inhibitor drug that has been studied extensively as an otoprotectant against noise, and suggests that KX2-329 could be useful for protection against noise.
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the role of oxidative stress in noise induced Hearing Loss
Ear and Hearing, 2006Co-Authors: Donald Henderson, Eric C Bielefeld, Kelly C HarrisAbstract:Modern research has provided new insights into the biological mechanisms of Noise-Induced Hearing Loss, and with these new insights comes hope for possible prevention or treatment. Underlying the classic set of cochlear pathologies that occur as a result of noise exposure are increased levels of reactive oxygen species (ROS) that play a significant role in Noise-Induced hair cell death. Both necrotic and apoptotic cell death have been identified in the cochlea. Included in the current review is a brief review of ROS, along with a description of sources of cochlear ROS generation and how ROS can damage cochlear tissue. The pathways of necrotic and apoptotic cell death are also reviewed. Interventions are discussed that target the prevention of Noise-Induced hair cell death: the use of antioxidants to scavenge and eliminate the damaging ROS, pharmacological interventions to limit the damage resulting from ROS, and new techniques aimed at interrupting the apoptotic biochemical cascade that results in the death of irreplaceable hair cells.
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prevention of impulse noise induced Hearing Loss with antioxidants
Acta Oto-laryngologica, 2005Co-Authors: Richard D Kopke, Donald Henderson, Eric C Bielefeld, Jianzhong Liu, Jiefu Zheng, Ronald L Jackson, John K M ColemanAbstract:Conclusion These findings indicate a strong protective effect of ALCAR and NAC on impulse Noise-Induced cochlear damage, and suggest the feasibility of using clinically available antioxidant compounds to protect the ear from acute acoustic injury. Objective Reactive oxygen species have been shown to play a significant role in Noise-Induced Hearing Loss. In the current study, the protective effects of two antioxidants, acetyl-L-carnitine (ALCAR) and N-L-acetylcysteine (NAC), were investigated in a chinchilla model of Hearing Loss resulting from impulse noise. It was hypothesized that pre- and post-treatment with these antioxidants would ameliorate the effects of impulse noise compared to saline-treated controls. Material and methods Eighteen animals were randomly assigned to 1 of 3 groups and exposed to impulse noise at a level of 155 dB peak SPL for 150 repetitions. ALCAR or NAC were administered twice daily (b.i.d.) for 2 days and 1 h prior to and 1 h following noise exposure, and then b.i.d. for the fol...
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r phenylisopropyladenosine attenuates noise induced Hearing Loss in the chinchilla
Hearing Research, 1997Co-Authors: Xiang Yang Zheng, Sandra L Mcfadden, Richard D Kopke, Donald HendersonAbstract:Abstract Reactive oxygen species, which are cytotoxic to living tissues, are thought to be partly responsible for Noise-Induced Hearing Loss. In this study R-phenylisopropyladenosine (R-PIA), a stable non-hydrolyzable adenosine analogue which has been found effective in upregulating antioxidant enzyme activity levels, was topologically applied to the round window of the right ears of chinchillas. Physiological saline was applied to the round window of the left ears (control). The animals were then exposed to a 4 kHz octave band noise at 105 dB SPL for 4 h. Inferior colliculus evoked potential thresholds and distortion product otoacoustic emissions (DPOAE) were measured and hair cell damage was documented. The mean threshold shifts immediately after the noise exposure were 70–90 dB at frequencies between 2 and 16 kHz. There were no significant differences in threshold shifts at this point between the R-PIA-treated and control ears. By 4 days after noise exposure, however, the R-PIA-treated ears showed 20–30 dB more recovery than saline-treated ears at frequencies between 4 and 16 kHz. More importantly, threshold measurements made 20 days after noise exposure showed 10–15 dB less permanent threshold shifts in R-PIA-treated ears. The amplitudes of DPOAE also recovered to a greater extent and outer hair cell Losses were less severe in the R-PIA-treated ears. The results suggest that administration of R-PIA facilitates the recovery process of the outer hair cell after noise exposure.
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individual susceptibility to noise induced Hearing Loss an old topic revisited
Ear and Hearing, 1993Co-Authors: Donald Henderson, Malini Subramaniam, Flint A BoettcherAbstract:The wide range in susceptibility to Noise-Induced Hearing Loss has intrigued researchers and Hearing conservationists alike. Some of these differences in variability have been attributed to various intrinsic factors such as eye color, gender, age, etc. However, a review of controlled research shows that the influence of these intrinsic variables is relatively small and cannot explain the wide range of Hearing Loss observed in demographic studies. Furthermore, uncontrolled variables or unrecognized drug and noise interaction may obscure the relation between noise exposure and Hearing Loss. With the growing understanding of the physiology of the auditory system, new possibilities are emerging that may explain the range of susceptibility. A review of the role of acoustic reflex effectiveness, cochlear efferent function, and history of noise exposure provide a perspective for future strategies in predicting susceptibility to Noise-Induced Hearing Loss.
Baoli Zhu - One of the best experts on this subject based on the ideXlab platform.
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single nucleotide polymorphisms in jnk1 are associated with susceptibility to noise induced Hearing Loss in a chinese population
International Archives of Occupational and Environmental Health, 2021Co-Authors: Dawei Sun, Boshen Wang, Haoran Guo, Ning Wang, Dengfeng Gao, Baoli ZhuAbstract:Purpose This study intended to explore the effect of C-Jun N-terminal kinases 1 (JNK1) polymorphisms on the sensitivity of individual Hearing Loss. Methods A total of 1333 subjects, including 683 NIHL workers and 650 normal-Hearing workers from east China, were included in this cross-sectional study. Genotyping of three JNK1 single nucleotide polymorphisms (rs9284, rs8428, and rs11598320) was performed. The relationship between different genotypes and Noise-Induced Hearing Loss was analyzed. Results Results show that rs11598320 TT genotype was associated with a higher risk of NIHL (OR 1.57, 95% CI 0.91-2.70). Stratified analysis indicated that the rs11598320 AT + AA genotype was associated with a decreased risk of Hearing Loss in subjects exposed to noise ≤ 16 years or a noise level > 92 dB (OR 0.68, 95% CI 0.50-0.93 and OR 0.64, 95% CI 0.42-0.96, respectively). The rs8428 TT genotype was associated with an increased risk of Noise-Induced Hearing Loss when the noise level was > 92 dB (OR 1.73, 95% CI 1.11-2.70). Haplotype TCT (rs9284-rs8424-rs11598320) was associated with an increased risk of Noise-Induced Hearing Loss (OR 1.30, 95% CI 1.00-1.68). Conclusion Single nucleotide polymorphisms (rs11598320 and rs8424) in JNK1 can be used as new biomarkers of susceptibility for Noise-Induced Hearing Loss in Chinese workers.
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polymorphisms in the fas gene are associated with susceptibility to noise induced Hearing Loss
Environmental Science and Pollution Research, 2021Co-Authors: Boshen Wang, Baoli Zhu, Lei Han, Juan ZhangAbstract:This study investigated the relationship between genetic polymorphisms in the FAS gene and Noise-Induced Hearing Loss (NIHL) risk among Chinese workers exposed to occupational noise, and the molecular mechanism of NIHL caused by noise. In this case-control study, 692 NIHL workers and 650 controls were selected for genotyping of four single nucleotide polymorphisms (SNPs) of the FAS gene. Logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (CI) of the association of these genetic polymorphisms and NIHL. At the same time, a noise-exposed rat model was constructed to further clarify the effect of noise exposure on fas gene expression and the pathogenic mechanism of NIHL. Two polymorphisms, rs1468063 and rs2862833, were associated with NIHL in the case-control study. Individuals with the rs1468063-TT or rs2862833-AA genotypes had decreased NIHL risk (p < 0.01, p = 0.02, respectively). Compared with the control group, the Hearing threshold of the case group of rats increased, while serum MDA, urine 8-OHdG, and fas gene expression increased, but let-7e expression decreased. Genetic polymorphisms in the FAS gene are related to the risk of NIHL in the Chinese population. Noise can cause a large amount of reactive oxygen species (ROS) in the cochlea tissue and blood, which lead to oxidative stress, lipid peroxidation, and DNA damage, further activating the FAS gene, and ultimately leading to Hearing Loss.
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association of dnmt3a s single nucleotide polymorphisms with susceptibility to noise induced Hearing Loss in chinese workers
Journal of hygiene research, 2018Co-Authors: Haoran Guo, Hengdong Zhang, Jian Cheng, Rongjian Sheng, Wenyan Cai, Yiliang Xin, Enmin Ding, Baoli ZhuAbstract:OBJECTIVE To investigate the potential association of DNMT3a's single nucleotide polymorphism with susceptibility to Noise-Induced Hearing Loss( NIHL) in Chinese noise-exposed workers. METHODS A case-control study was performed, and 998 noise-exposed workers from a chemical fibre factory and an energy company, who underwent occupational health examination in 2015, were enrolled as study subjects. Then, general information and noise exposure of the study subjects were obtained through questionnaire survey and on-site noise detection. According to the result of audiological evaluation, they were divided into case group( n = 498, high-frequency threshold shift >25 dB) and man-matched control group( n = 500, high-frequency threshold shift ≤25 dB). At last, genotyping of DNMT3a rs7590760 was conducted with TaqMan-PCR technique. RESULTS In the dominant model, the distribution of rs7590760 genotypes between the case group and the control group was statistically significant( P = 0. 001). The NIHL risk of subjects with CC/CG genotype is 1. 56 times the risk of those carrying GG genotype, with an adjusted OR = 1. 56( 95% CI 1. 22-2. 01). After the noise exposure period and noise exposure intensity were stratified, the adjusted OR values for noise exposure period ≤16 years, > 16 years and noise intensity ≤85, 86-92 and >92 dB were respectively 1. 67( 95% CI 1. 17-2. 38), 1. 52( 95% CI 1. 06-2. 17), 1. 56( 95% CI 1. 06-2. 30), 1. 67( 95% CI 0. 94-2. 99) and 1. 51( 95% CI 1. 01-2. 26). CONCLUSION The CC/CG genotype of rs7590760 in DNMT3a gene is a potential risk factor for Noise-Induced Hearing Loss in Chinese noise-exposed workers.
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pon2 and atp2b2 gene polymorphisms with noise induced Hearing Loss
Journal of Thoracic Disease, 2016Co-Authors: Jinglian Cao, Jun Wang, Haiyan Song, Qiu Dong, Chunlong Wei, Ying Cao, Boshen Wang, Baoli Zhu, Hang XiaoAbstract:Background: Noise-Induced Hearing Loss (NIHL) is a complex disease induced by a combination of genetic and environmental factors. Paraoxonase2 ( PON2 ) gene involved in the regulation of reactive oxygen species, and affecting the vulnerability of cochlea to NIHL, and ATPase, calcium-transporting, plasma membrane 2 ( ATP2B2 ) gene which encodes plasma membrane calcium-transporting ATPase isoform 2 (PMCA2) are the candidate genes relating to the attack of NIHL. In this study, we investigated whether ATP2B2 and PON2 polymorphisms were associated with NIHL in Chinese of Han nationality population. Methods: We performed a case-control study between six single nucleotide polymorphisms (SNPs) (rs1719571, rs3209637 and rs4327369 within ATP2B2 , rs12026, rs7785846 and rs12704796 within PON2 ) and NIHL in 454 subjects. All the SNPs were genotypes, using the TaqMan MGB probe assay. Odds ratios (ORs) were calculated with 95% confidence intervals (95% CIs) with logistic regression analysis to test the level of association for SNPs. Results: In our study, 221 subjects with Hearing Loss and 233 subjects without Hearing Loss were recruited. The frequencies of the CG and CG + GG genotype of rs12026 ( PON2 ) conferred risk factors for NIHL with adjusted OR values of 2.62 (95% CI, 1.69–4.06) and 2.48 (95% CI, 1.63–3.78), respectively. This kind of significance was also found at locus rs7785846, where genotypes CT and CT + TT were the risk types, with adjusted ORs of 2.52 (95% CI, 1.62–3.93) and 2.35 (95% CI, 1.54–3.58), respectively. We performed stratified analysis per noise exposure level, when it came to rs7785846 and rs12026 in the >92 dB(A) noise exposure group, the subjects who carried heterozygote were of significantly (P ATP2B2 (P>0.05), which may suggest that these SNPs did not have significant effects on noise susceptibility across noise exposure. Conclusions: Our research suggested that PON2 might play a role in the etiology of NIHL in Chinese of Han nationality population.
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genetic variation in gstm1 is associated with susceptibility to noise induced Hearing Loss in a chinese population
Journal of Occupational and Environmental Medicine, 2012Co-Authors: Huanxi Shen, Xinying Huo, Kai Liu, Wei Gong, Hengdong Zhang, Meilin Wang, Jing Zhang, Zhengdong Zhang, Baoli ZhuAbstract:Objectives:To investigate whether glutathione S-transferases (GST) genetic polymorphisms (GSTT1 rs1049055, GSTM1 rs10712361, and GSTP1 rs1695) are associated with susceptibility to Noise-Induced Hearing Loss (NIHL).Methods:These polymorphisms were analyzed in 444 NIHL and 445 normal Hearing workers.
Michael G Heinz - One of the best experts on this subject based on the ideXlab platform.
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the chinchilla animal model for Hearing science and noise induced Hearing Loss
Journal of the Acoustical Society of America, 2019Co-Authors: Monica Trevino, Edward Lobarinas, Amanda C Maulden, Michael G HeinzAbstract:The chinchilla animal model for Noise-Induced Hearing Loss has an extensive history spanning more than 50 years. Many behavioral, anatomical, and physiological characteristics of the chinchilla make it a valuable animal model for Hearing science. These include similarities with human Hearing frequency and intensity sensitivity, the ability to be trained behaviorally with acoustic stimuli relevant to human Hearing, a docile nature that allows many physiological measures to be made in an awake state, physiological robustness that allows for data to be collected from all levels of the auditory system, and the ability to model various types of conductive and sensorineural Hearing Losses that mimic pathologies observed in humans. Given these attributes, chinchillas have been used repeatedly to study anatomical, physiological, and behavioral effects of continuous and impulse noise exposures that produce either temporary or permanent threshold shifts. Based on the mechanistic insights from noise-exposure studies, chinchillas have also been used in pre-clinical drug studies for the prevention and rescue of Noise-Induced Hearing Loss. This review paper highlights the role of the chinchilla model in Hearing science, its important contributions, and its advantages and limitations.The chinchilla animal model for Noise-Induced Hearing Loss has an extensive history spanning more than 50 years. Many behavioral, anatomical, and physiological characteristics of the chinchilla make it a valuable animal model for Hearing science. These include similarities with human Hearing frequency and intensity sensitivity, the ability to be trained behaviorally with acoustic stimuli relevant to human Hearing, a docile nature that allows many physiological measures to be made in an awake state, physiological robustness that allows for data to be collected from all levels of the auditory system, and the ability to model various types of conductive and sensorineural Hearing Losses that mimic pathologies observed in humans. Given these attributes, chinchillas have been used repeatedly to study anatomical, physiological, and behavioral effects of continuous and impulse noise exposures that produce either temporary or permanent threshold shifts. Based on the mechanistic insights from noise-exposure studies...
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the chinchilla animal model for Hearing science and noise induced Hearing Loss
Journal of the Acoustical Society of America, 2019Co-Authors: Monica Trevino, Edward Lobarinas, Amanda C Maulden, Michael G HeinzAbstract:The chinchilla animal model for Noise-Induced Hearing Loss has an extensive history spanning more than 50 years. Many behavioral, anatomical, and physiological characteristics of the chinchilla make it a valuable animal model for Hearing science. These include similarities with human Hearing frequency and intensity sensitivity, the ability to be trained behaviorally with acoustic stimuli relevant to human Hearing, a docile nature that allows many physiological measures to be made in an awake state, physiological robustness that allows for data to be collected from all levels of the auditory system, and the ability to model various types of conductive and sensorineural Hearing Losses that mimic pathologies observed in humans. Given these attributes, chinchillas have been used repeatedly to study anatomical, physiological, and behavioral effects of continuous and impulse noise exposures that produce either temporary or permanent threshold shifts. Based on the mechanistic insights from noise-exposure studies, chinchillas have also been used in pre-clinical drug studies for the prevention and rescue of Noise-Induced Hearing Loss. This review paper highlights the role of the chinchilla model in Hearing science, its important contributions, and its advantages and limitations.
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envelope coding in auditory nerve fibers following noise induced Hearing Loss
Jaro-journal of The Association for Research in Otolaryngology, 2010Co-Authors: Sushrut Kale, Michael G HeinzAbstract:Recent perceptual studies suggest that listeners with sensorineural Hearing Loss (SNHL) have a reduced ability to use temporal fine-structure cues, whereas the effects of SNHL on temporal envelope cues are generally thought to be minimal. Several perceptual studies suggest that envelope coding may actually be enhanced following SNHL and that this effect may actually degrade listening in modulated maskers (e.g., competing talkers). The present study examined physiological effects of SNHL on envelope coding in auditory nerve (AN) fibers in relation to fine-structure coding. Responses were compared between anesthetized chinchillas with normal Hearing and those with a mild–moderate Noise-Induced Hearing Loss. Temporal envelope coding of narrowband-modulated stimuli (sinusoidally amplitude-modulated tones and single-formant stimuli) was quantified with several neural metrics. The relative strength of envelope and fine-structure coding was compared using shuffled correlogram analyses. On average, the strength of envelope coding was enhanced in noise-exposed AN fibers. A high degree of enhanced envelope coding was observed in AN fibers with high thresholds and very steep rate-level functions, which were likely associated with severe outer and inner hair cell damage. Degradation in fine-structure coding was observed in that the transition between AN fibers coding primarily fine structure or envelope occurred at lower characteristic frequencies following SNHL. This relative fine-structure degradation occurred despite no degradation in the fundamental ability of AN fibers to encode fine structure and did not depend on reduced frequency selectivity. Overall, these data suggest the need to consider the relative effects of SNHL on envelope and fine-structure coding in evaluating perceptual deficits in temporal processing of complex stimuli.
Richard D Kopke - One of the best experts on this subject based on the ideXlab platform.
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prevention of impulse noise induced Hearing Loss with antioxidants
Acta Oto-laryngologica, 2005Co-Authors: Richard D Kopke, Donald Henderson, Eric C Bielefeld, Jianzhong Liu, Jiefu Zheng, Ronald L Jackson, John K M ColemanAbstract:Conclusion These findings indicate a strong protective effect of ALCAR and NAC on impulse Noise-Induced cochlear damage, and suggest the feasibility of using clinically available antioxidant compounds to protect the ear from acute acoustic injury. Objective Reactive oxygen species have been shown to play a significant role in Noise-Induced Hearing Loss. In the current study, the protective effects of two antioxidants, acetyl-L-carnitine (ALCAR) and N-L-acetylcysteine (NAC), were investigated in a chinchilla model of Hearing Loss resulting from impulse noise. It was hypothesized that pre- and post-treatment with these antioxidants would ameliorate the effects of impulse noise compared to saline-treated controls. Material and methods Eighteen animals were randomly assigned to 1 of 3 groups and exposed to impulse noise at a level of 155 dB peak SPL for 150 repetitions. ALCAR or NAC were administered twice daily (b.i.d.) for 2 days and 1 h prior to and 1 h following noise exposure, and then b.i.d. for the fol...
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reduction of noise induced Hearing Loss using l nac and salicylate in the chinchilla
Hearing Research, 2000Co-Authors: Richard D Kopke, Ronald L Jackson, Peter Weisskopf, John L Boone, Derin Wester, Michael E Hoffer, David LambertAbstract:The effects of a combination of two antioxidant compounds were studied in a chinchilla model of Noise-Induced Hearing Loss. After obtaining baseline Hearing thresholds using inferior colliculus evoked potentials, chinchillas were exposed for 6 h to octave band noise centered at 4 kHz (105 dB SPL). Post-noise thresholds were obtained 1 h after the noise exposure, and then animals received either saline or salicylate and N-L-acetylcysteine combination. Another group received antioxidant treatment 1 h prior to noise. Hearing was tested at 1, 2 and 3 weeks post-noise. Subsequently, the cochleae were harvested, and cytocochleograms were prepared. There was a 20–40 dB SPL threshold shift at 3 weeks for tested controls. Permanent threshold shifts (PTS) were significantly reduced (P<0.05) to approximately 10 dB for the pre-treatment group at week 3. The PTS for the post-treatment group at week 3 was similar to the pre-treatment group at 1 and 2 kHz (0–10 dB) but was intermediate between the control and pre-treatment groups at 4 and 8 kHz (23 dB). Animals pre-treated with antioxidant had a significant reduction in hair cell Loss but those post-treated with antioxidant had no protection from hair cell Loss. These findings demonstrate the feasibility of reduction of Noise-Induced Hearing Loss using clinically available antioxidant compounds.
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r phenylisopropyladenosine attenuates noise induced Hearing Loss in the chinchilla
Hearing Research, 1997Co-Authors: Xiang Yang Zheng, Sandra L Mcfadden, Richard D Kopke, Donald HendersonAbstract:Abstract Reactive oxygen species, which are cytotoxic to living tissues, are thought to be partly responsible for Noise-Induced Hearing Loss. In this study R-phenylisopropyladenosine (R-PIA), a stable non-hydrolyzable adenosine analogue which has been found effective in upregulating antioxidant enzyme activity levels, was topologically applied to the round window of the right ears of chinchillas. Physiological saline was applied to the round window of the left ears (control). The animals were then exposed to a 4 kHz octave band noise at 105 dB SPL for 4 h. Inferior colliculus evoked potential thresholds and distortion product otoacoustic emissions (DPOAE) were measured and hair cell damage was documented. The mean threshold shifts immediately after the noise exposure were 70–90 dB at frequencies between 2 and 16 kHz. There were no significant differences in threshold shifts at this point between the R-PIA-treated and control ears. By 4 days after noise exposure, however, the R-PIA-treated ears showed 20–30 dB more recovery than saline-treated ears at frequencies between 4 and 16 kHz. More importantly, threshold measurements made 20 days after noise exposure showed 10–15 dB less permanent threshold shifts in R-PIA-treated ears. The amplitudes of DPOAE also recovered to a greater extent and outer hair cell Losses were less severe in the R-PIA-treated ears. The results suggest that administration of R-PIA facilitates the recovery process of the outer hair cell after noise exposure.
K K Deepak - One of the best experts on this subject based on the ideXlab platform.
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occupational noise induced Hearing Loss in indian steel industry workers an exploratory study
Human Factors, 2013Co-Authors: Lakhwinder Pal Singh, Arvind Bhardwaj, K K DeepakAbstract:Objective:The present study focused on exploring the current level of Hearing protection and subsequently determined the prevalence of occupational Noise-Induced Hearing Loss among casting and forging industry workers.Background:The casting and forging industry provides employment to a significant portion of the population.Method:The level of Hearing protection was assessed through questionnaire survey of 572 workers. Out of these workers, 165 and another control group of 57 participants were assessed by formal audiometry. Audiometric tests were conducted at frequencies of 1.0 KHz to 8.0 KHz. The occurrence of Hearing Loss was determined on the basis of a Hearing threshold level with a low fence of 25 dB. Student’s test and ANOVA were used to compare the various groups; a p value <.05 was considered statistically significant.Results:More than 90% of the workers sampled showed significant Hearing Loss at medium and high frequencies. The analyses revealed a higher prevalence of significant Hearing Loss amon...