Apoptosis in inner ear sensory hair cells

摘要:Apoptosis, or controlled cell death, is a normal part of cellular lifespan. Cell death of cochlear hair cells causes deafness;an apoptotic process that is not well understood. Worldwide, 1.3 billion humans suffer some form of hearing loss, while 360 million suffer debilitating hearing loss as a direct result of the absence of these cochlear hair cells (Worldwide Hearing, 2014). Much is known about apoptosis in other systems and in other cell types thanks to studies done since the mid-20th century. Here we review current literature on apoptosis in general, and causes of deafness and cochlear hair cells loss as a result of apoptosis. The family of B-cell lymphoma (Bcl) proteins are among the most studied and characterized. We will review current literature on the Bcl2 and Bcl6 protein interactions in relation to apoptosis and their possible roles in vulnerability and survival of cochlear hair cells.

cochlear hair cellshearing lossprotein interactionscell deathas a result ofform of
被引:8
Intratympanic corticosteroids in Ménière's disease: A mini-review

摘要:This article reviews the effectiveness of intratympanic corticosteroids for vertigo control in Ménière's disease at 2-years follow-up according to the guidelines expressed by the American Academy of Otolaryngology-Head & Neck Surgery. Despite the increased use of intratympanic corticosteroids for vertigo control in Ménière's disease there is debate as to their effectiveness, particularly compared to gentamicin. Even so, after just a single course of injections, corticosteroids can reliably provide complete vertigo control (Class A) at 2-years in about 50% of cases as indicated in a recent double-blind randomized controlled clinical trial (Patel et al., 2016). But the effectiveness of intratympanic corticosteroids truly increases when treatment is provided 'as-needed', whereby complete vertigo control is established in up to 91% of cases. On the basis of available literature, there is good evidence to recommend the use of intratympanic steroid treatment for vertigo control in Ménière's disease, but patients must be monitored for non-response. The rationale for treating patients as-needed and the possible reasons for corticosteroid non-response are discussed.

clinical trial
被引:8
Assessment of outcomes of hearing and speech rehabilitation in children with cochlear implantation

摘要:Objectives:This study aimed to assess the effect of hearing and speech rehabilitation in patients with Nurotron(R) cochlear implants.Design:Ninety-eight paediatric patients with bilateral severe-to-profound sensorineural deafness who received cochlear implantation were divided into three groups according to age:group A (≤3 years),group B (4-7 years),and group C (8-16 years).All patients were followed up for one year for hearing and speech performance after the surgery.The comprehensive Auditory Perception Assessment,MAIS,CAP and SIR hearing and speech assessments and rating materials were used for assessment before the surgery and at 3,6,and 12 months after implant activation.Results:The scores of patients in the open-set speech assessment,Chinese Auditory Perception Assessment,MAIS,CAP and SIR significantly improved after cochlear implantation in all age groups.The younger the age at implantation,the better the results.Moreover,the hearing and speech performance of cochlear implant recipients gradually improved with the extension of rehabilitation time.Conclusions:Nurotron(R) VenusTM cochlear implantation can improve the hearing and speech performance of patients with bilateral severe-to-profound sensorineural deafness.

被引:7
Spatial learning and memory deficits in young adult mice exposed to a brief intense noise at postnatal age

摘要:Noise pollution is a major hazardous factor to human health and is likely harmful for vulnerable groups such as pre-term infants under life-support system in an intensive care unit. Previous studies have suggested that noise exposure impairs children's learning ability and cognitive performance and cognitive functions in animal models in which the effect is mainly attributed to the oxidant stress of noise on the cognitive brain. The potential role of noise induced hearing loss (NIHL), rather than the oxidant stress, has also been indicated by a depression of neurogenesis in the hippocampus long after a brief noise exposure, which produces only a tentative oxidant stress. It is not clear if noise exposure and NIHL during early development exerts a long term impact on cognitive function and neurogenesis towards adulthood. In the present study, a brief noise exposure at high sound level was performed in neonatal C57BL/6J mice (15 days after birth) to produce a significant amount of permanent hearing loss as proved 2 months after the noise. At this age, the noise-exposed animals showed deteriorated spatial learning and memory abilities and a reduction of hippocampal neurogenesis as compared with the control. The averaged hearing threshold was found to be strongly correlated with the scores for spatial learning and memory. We consider the effects observed are largely due to the loss of hearing sensitivity, rather than the oxidant stress, due to the long interval between noise exposure and the observations.

noise exposureoxidant stresslearning and memoryinduced hearing lossintensive care unitcognitive functionearly developmentlearning abilityloss of hearinganimal modelshuman healthsound level
被引:7下载:1
Inner ear barriers to nanomedicine-augmented drug delivery and imaging

摘要:There are several challenges to inner ear drug delivery and imaging due to the existence of tight biological barriers to the target structure and the dense bone surrounding it. Advances in imaging and nanomedicine may provide knowledge for overcoming the existing limitations to both the diagnosis and treatment of inner ear diseases. Novel techniques have improved the efficacy of drug delivery and targeting to the inner ear, as well as the quality and accuracy of imaging this structure. In this review, we will describe the pathways and biological barriers of the inner ear regarding drug delivery, the beneficial applications and limitations of the imaging techniques available for inner ear research, the behavior of engineered nanomaterials in inner ear applications, and future perspectives for nanomedicine-based inner ear imaging.

inner eardrug deliverydiagnosis and treatment
被引:7
Deep Brain Stimulation——A new treatment for tinnitus

摘要:Intractable tinnitus can lead to serious consequences. Study evidence indicates that the central nervous system is involved in generation and maintenance of chronic tinnitus and that tinnitus and other neurologic symptoms such as chronic pain may share similar mechanisms. Brain ablation and stimulation are used to treat chronic pain with success. Recent studies showed that ablation and stimulation in non-auditory areas resulted in tinnitus improvement. Deep brain stimulation (DBS) may be an alternative treatment for intractable tinnitus and deserves further study.

chronic paincentral nervous system
被引:7
Mitochondrial DNA A1555G mutation screening using a testing kit method and its significance in preventing aminoglycoside-related hearing loss

摘要:To report a new screening method for mitochondrial DNA 1555A→G mutation and the results of genotype analysis in 19 maternal inherited deafness pedigrees. Method Five hundred and forty-six non-syndromic neuro-sensory hearing loss patients were tested for 1555A→G mutation using a new compact testing kit, which allows clear distinction between wild type and 1555 A→G mutated mtDNAs. Results Nineteen subjects among the 546 patients (3.48%) were found to carry mtDNA A1555G mutation. The results were confirmed by sequencing in an ABI 3100 Avant sequencer. Conclusions Maternal inherited deafness families are a frequently seen in outpatient group. The detection ofmtDNA 1555 A→G mutation with a low cost, ready to use detection kit is needed and suitable in China for large scale screening and preventive testing before usage of aminoglycoside antibiotics.

aminoglycoside antibioticsmitochondrial DNAscreening methodhearing losswild typelow cost
被引:7
OTOTOXIC MODEL OF OXALIPLATIN AND PROTECTION FROM NICOTINAMIDE ADENINE DINUCLEOTIDE

摘要:Oxaliplatin, an anticancer drug commonly used to treat colorectal cancer and other tumors, has a number of serious side effects, most notably neuropathy and ototoxicity. To gain insights into its ototoxic profile, oxaliplatin was applied to rat cochlear organ cultures. Consistent with it neurotoxic propensity, oxaliplatin selectively damaged nerve fibers at a very low dose 1 μM. In contrast, the dose required to damage hair cells and spiral ganglion neurons was 50 fold higher (50 μM). Oxailiplatin-induced cochlear lesions initial-ly increased with dose, but unexpectedly decreased at very high doses. This non-linear dose response could be related to depressed oxaliplatin uptake via active transport mechanisms. Previous studies have demon-strated that axonal degeneration involves biologically active processes which can be greatly attenuated by nicotinamide adenine dinucleotide (NAD+). To determine if NAD+would protect spiral ganglion axons and the hair cells from oxaliplatin damage, cochlear cultures were treated with oxaliplatin alone at doses of 10 μM or 50 μM respectively as controls or combined with 20 mM NAD+. Treatment with 10 μM oxaliplatin for 48 hours resulted in minor damage to auditory nerve fibers, but spared cochlear hair cells. However, when cochlear cultures were treated with 10 μM oxaliplatin plus 20 mM NAD+, most auditory nerve fibers were intact. 50 μM oxaliplatin destroyed most of spiral ganglion neurons and cochlear hair cells with apop-totic characteristics of cell fragmentations. However, 50 μM oxaliplatin plus 20 mM NAD+treatment great-ly reduced neuronal degenerations and hair cell missing. The results suggested that NAD+provides signifi-cant protection against oxaliplatin-induced neurotoxicity and ototoxicity, which may be due to its actions of antioxidant, antiapoptosis, and energy supply.

spiral ganglion neuronscochlear hair cellsnerve fibersprotection againstcolorectal canceractive transportanticancer drugenergy supplyside effects
被引:7
Case of Waardenburg Shah syndrome in a family with review of literature

摘要:Waardenburg syndrome is a rare disease characterized by sensorineural deafness in association with pigmentary defects. Depending on additional symptoms, WS have been classified into four types. Waardenburg syndrome type 4, also called as Waardenburg Shah Syndrome is a very rare congenital disorder with astounding variable clinical expression, characterized by pigmentary abnormalities of the hair (A white forelock of hair, premature graying) and pigmentary changes of the iris such as heterochromia or homochromia irides, sensorineural deafness and Hirschsprung disease. Three genes have been bestowed so far in consociation with EDNRB, EDN3, and SOX10 genes. The pattern of inheritance is multifarious with the SOX10 mutation affiliation with autosomal dominant inheritance whereas the EDNRB and EDN3 genes are passed down in an autosomally recessive pattern.

被引:6
Adenoviral-mediated Hath1-EGFP gene transfer into guinea pig cochlea through intact round window membrane

摘要:Objective To study expression of adenovira1-mediated Hathl-EGFP gene in the guinea pig cochlea after transfer through intact round window membrane (RWM), and to assess its effects on hearing. Methods Twenty adult guinea pigs were used, of which: 12 were surgically inoculated with AdHath1-EGFP in the bony groove of round window niche, and 8 with artificial perilymph. Auditory brainstem response(ABR) thresholds were determined in all animals before and 5 days after surgery. On post-surgery day 5 and day 14, animals were sacrificed and whole mounts of cochlea and fro zensections were examined. Results ABR tests showed no significant change of hearing after the surgery.Strong fluorescence staining in the cochleae was seen in Ad-Hathl-EGFP groups. The highest levels of gene expression were seen in the post-surgery day 5 group with tittle decrease on post-surgery day 14.The contralateral cochlea and those in the control groups were free of fluorescence staining. Conclusion The transgenic Hath1-EGFP can be effectively delivered into the inner ear through intact RWM, in an atraumatic manner.

guinea pigsgene expressioninner ear
被引:6
NOISE INDUCED HEARING LOSS IN CHINA:A POTENTIALLY COSTLY PUB-LIC HEALTH LSSUE

摘要:Hearing loss and tinnitus are among the most common consequences of long term noise exposure and re-main an under-addressed heath issue in most developing nations including China. The rapid industrializa-tion and life style changes in China increase the concern over noise exposure and noise induced hearing loss (NIHL). Research on NIHL in China is limited. The current paper reviews studies published in English and Chinese language literatures regarding noise exposure and NIHL in China. Their implication on the Chi-nese population is discussed. The possible utility of a research model such as the Dangerous Decibels? as a means to increase understanding of the scope of NIHL among the Chinese population, to educate the gener-al public in China (especially the young) about NIHL and its prevention, and to study effects of language and cultural factors on international information dissemination and behavioral interventions is proposed.

noise exposureinformation disseminationinduced hearing lossChinese populationcultural factorsChinese languagelife style
被引:6
One-stage coclear implantation via a facial recess approach in children with otitis media with effusion

摘要:Objective:To investigate surgical indications, operative techniques, complications and auditory and speech rehabilitation for cochlear implant (CI) in children with otitis media with effusion (OME). <br> Material and methods:This is a retrospective review of records of 24children with bilateral profound sensorineural hearing loss and OME who were implanted during January 2011 to November 2014 in the Department of Otorhinolaryngology and Head and Neck Surgery at the PLA Hospital, using one-stage implantation via the facial recess approach and round window insertion. The incus was removed in 8 cases during the implantation procedure. Local infiltration of dexamethasone and adrenaline in the middle ear was also performed. Postoperative complications were examined. Preoperative and postoperative questionnaires including Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR), and the Meaningful Auditory Integration Scale (MAIS) were collected. <br> Results: All electrodes were implanted successfully without any immediate or delayed complications. Inflammatory changes of middle ear mucosa with effusion were noted in all implanted ears. The scores of post-implant CAP and SIR increased significantly in all 24 cases (t ? ?25.95 and ?14.09, respectively for CAP and SIR, p<0.05). <br> Conclusions:One-stage CI via the facial recess approach with round window insertion is safe and effective in cochlear implant candidates with OME, as seen in the 24 children in our study who achieved improved auditory performance and speech intelligibility after CI. <br> Copyright ? 2015, PLA General Hospital Department of Otolaryngology Head and Neck Surgery. Production and hosting by Elsevier (Singapore) Pte Ltd. This is an open access article under the CC BY-NC-ND license (

speech intelligibilitysensorineural hearing lossotitis media with effusionmiddle earopen access
被引:6
Optimizing CT for the evaluation of vestibular aqueduct enlargement:Inter-rater reproducibility and predictive value of reformatted CT measurements

摘要:Enlarged vestibular aqueduct (EVA), the most frequent identifiable cause of congenital hearing loss, is evaluated with high-definition multi-detector CT in the axial plane. Our purpose was to determine which reformatted CT measurements are most reproducible. Seven multiplanar reformatted images were created for each of the 64 temporal bones in patients with EVA. Intraclass correlation coefficients (ICC) were used to assess inter-observer variability, and both linear regression and ROC analyses were used to compare the measurements with severity of hearing loss, as assessed by pure tone audiometry. All seven measurements had excellent inter-observer variability, with average-measure ICC ranging from 0.92 to 0.98. There was no statistically significant correlation between the radiologic degree of aqueduct enlargement and severity of hearing loss using any of the seven measurements;ROC analyses revealed areas under the curves ranging from 0.57 to 0.73. Optimal accuracy was obtained with a threshold of 1.75 mm as measured at the aqueductal aperture in the P€oschl plane, with sensitivity of 0.75 and specificity of 0.63. Although the radiologic measurement may not serve as a reliable tool for assessing severity of EVA, P€oschl plane reformatting has proven to be better than conventional axial acquisition plane for identifying patients with clinically significant hearing loss.

hearing losslinear regression
被引:6
Association of asymptomatic otitis media with effusion in patients with adenoid hypertrophy

摘要:Objective:Clinical symptoms of otitis media with effusion are rarely brought forward to the guardians of young children who the disease is most prevalent in.This often leads to poor scholastic performances and difficult social interactions.The objective of this study was to identify asymptomatic cases of otitis media with effusion present in individuals with adenoid hypertrophy.Material and Methods:In a cross sectional study advocated in Justice K.S.Hegde Hospital,Karnataka India we evaluated one hundred patients above the age of three from August 2016 to December 2017.Candidates who presented with an adenoid nasopharyngeal ratio of more than 0.5 were selected for the study.Individuals who complained of otological symptoms were not considered for the study.Patients cleared of other pathological otological conditions were underwent audiological evaluation with pure tone audiometry and tympanometry for evaluating the middle ear status and hearing loss.Results:The study showed a total of 36% of patients evaluated presented with asymptomatic otitis media with effusion.In candidates who presented with a bilateral B tympanogram,40% had significant conductive hearing loss of more than 25dB.Conclusion:An objective test such as impedance audiometry in all patients with adenoid hypertrophy would aid in the diagnosis of fluid in the middle ear,so that timely intervention can be done and possible complications be averted.

被引:6
Probable benign paroxysmal positional vertigo, spontaneously resolved: Incidence in medical practice, patients' characteristics and the natural course

摘要:Background:Probable benign paroxysmal positional vertigo,spontaneously resolved (pBPPVsr),is a variant of benign paroxysmal positional vertigo (BPPV) in which there is no observable nystagmus and no vertigo with any positional maneuver.Objectives:To calculate the incidence pBPPVsr,compare the characteristics of the patients with pBPPVsr and BPPV not spontaneously resolved and describe the spontaneous resolution in the natural course of BPPV.Methods:Multicenter prospective descriptive study.During a one-year period,all patients with suspected BPPV that presented to the Neurotology Units of five participating centers were recruited.The incidence of pBPPVsr was calculated as a percentage of the total number of patients with BPPV.The prevalence of several variables was compared between pBPPVsr and BPPV not spontaneously resolved.The timing of spontaneous resolution was estimated using Kaplan-Meier curves.Results:457 patients met the inclusion criteria.The incidence of pBPPVsr was 33.5%.It was significantly higher in males,in patients with normal bone mass and in patients who were not taking sulpiride,A rate of 18% of spontaneous resolution after the first month and 51% after the first year was found.This percentage did not change in a significant way after this moment.The curves for males,patients under 50 and patients with normal blood pressure decreased significantly faster.Conclusions:In our serie,BPPV spontaneously resolved in half of the patients with BPPV during the first year.This seemed to occur more commonly in males and could have been hindered by sulpiride intake,osteoporosis,advanced age and high blood pressure.

被引:5
MUSIC AND COCHLEAR IMPLANTS

摘要:Currently, most people with modern multichannel cochlear implant systems can understand speech in qui-et environment very well. However, studies in recent decades reported a lack of satisfaction in music percep-tion with cochlear implants. This article reviews the literature on music ability of cochlear implant users by presenting a systematic outline of the capabilities and limitations of cochlear implant recipients with regard to their music perception as well as production. The review also evaluates the similarities and differences be-tween electric hearing and acoustic hearing regarding music perception. We summarize the research results in terms of the individual components of music (e.g., rhythm, pitch, and timbre). Finally, we briefly intro-duce the vocal singing of prelingually-deafened children with cochlear implants as evaluated by acoustic measures.

cochlear implantsresearch results
被引:5
Aging and the peripheral vestibular system

摘要:Whereas much has been learned about age-related auditory changes in the inner ear, relatively little is known about the aging effects on the vestibular part of the inner ear-the peripheral vestibular system. Here we review relevant literature with regard to the prevalence of vestibular dysfunction, vestibular functional and structural changes in the elderly. The prevalence of vestibular dysfunction increases with age. Functionally, as age in-creases, VEMP amplitudes decrease, VEMP thresholds increase, VOR gain of HIT decreases. Due to the com-plexity of the vestibular system, variations in subject age and measurement techniques, findings in VEMP latency and caloric tests are conflicting. To address this, a direct measure of the peripheral vestibular system should be applied. Structurally, age-related loss in vestibular ganglion and otoconia have been noted; hair cell changes are not well defined; while subcellular changes remain to be explored. Defining how the onset of vestibular dys-function correlates with structural degeneration will offer insights into the mechanisms underlying vestibular aging.

被引:5下载:1