Objective:The aims of this study were to investigate the clinical applicability of 3D segmentation in measuring cochlear anatomical parameters,explore factors that influence the insertion angle of cochlear implant ele...Objective:The aims of this study were to investigate the clinical applicability of 3D segmentation in measuring cochlear anatomical parameters,explore factors that influence the insertion angle of cochlear implant electrodes in patients with inner ear malformations,and determine the value of 3D segmentation in predicting cochlear implant electrode insertion depth by simulating electrode implantation in a reconstructed 3D model.Methods:Data from 208 temporal bone CT scans of patients with a variety of inner ear malformations(including the CH,IP-Ⅰ,IP-Ⅱ,and IP-Ⅲtypes)who underwent cochlear implantation at our center were retrospectively analyzed.Preoperative temporal bone CT data were subjected to three-dimensional(3D)segmentation of the cochlea with a 3D slicer.Results:Cochlear malformation types,including IP typesⅠ(42 ears),Ⅱ(278ears),Ⅲ(20 ears),and CH(65 ears),were diagnosed and measured in 208 preoperative CT datasets.Cochlear anatomical parameters and electrode length were correlated,which partially explained the variations in electrode insertion angle.The mean angle of implantation among the enrolled patients was 564.33°,and the mean implantation angle prediction error in the 3D segmentation was|23.74|°.Conclusion:Three-dimensional segmentation from temporal bone CT is valuable for surgeons,especially in treating patients with inner ear malformation.Such insights will help surgeons understand overall anatomical variations,predict electrode implantation depth,and complete preoperative imaging assessments for cochlear implant insertion depth in patients with inner ear malformations.展开更多
ObjectiveTo develop a sustained-release codelivery system for intratympanic administration of dexamethasone(DEX)and lipoic acid(LA).MethodsDEX microcrystals(MCs)were prepared via precipitation,while LA-loaded porous P...ObjectiveTo develop a sustained-release codelivery system for intratympanic administration of dexamethasone(DEX)and lipoic acid(LA).MethodsDEX microcrystals(MCs)were prepared via precipitation,while LA-loaded porous PLGA microspheres(LPMPs)were fabricated using a double emulsion–solvent evaporation method.DEX MCs were physically perfused into LPMPs via negative pressure to form a combined system(DEX MCs+LPMPs).Physicochemical properties,in vitro drug release,pharmacokinetics,and biocompatibility were evaluated.Guinea pigs were used for intratympanic injections of DEX MCs,LPMPs,or DEX MCs+LPMPs.ResultsThe DEX MCs+LPMPs system enabled simultaneous release of both drugs,with DEX exhibiting superior pharmacokinetics(sustained perilymph concentrations up to 7 days)compared to DEX MCs alone.LA release from LPMPs demonstrated prolonged kinetics without burst release.SEM confirmed DEX MCs were localized within/on LPMPs and adhered to the round window membrane(RWM).Histological analysis revealed normal cochlear morphology and no inflammatory response,confirming biocompatibility.ConclusionsThis novel codelivery system combining microcrystals and porous microspheres achieves sustained dual-drug release,enhances therapeutic efficacy,and offers a promising strategy for managing hearing loss via intratympanic administration.展开更多
Background:Sudden sensorineural hearing loss(SSNHL),often associated with tinnitus,significantly impacts individuals'quality of life.Current treatments,such as free drugs via intravenous or intratympanic(IT)admini...Background:Sudden sensorineural hearing loss(SSNHL),often associated with tinnitus,significantly impacts individuals'quality of life.Current treatments,such as free drugs via intravenous or intratympanic(IT)administration of dexamethasone(DEX)and lidocaine,face limitations like low bioavailability and rapid drug clearance.To address these challenges,we developed a local co-delivery system combining DEX microcrystals(DEX MCs)and lidocaine-loaded poly(lactic-co-glycolic acid)(PLGA)non-spherical microparticles(LPNMs)for sustained drug release in the inner ear.Methods:DEX MCs and LPNMs were prepared using the traditional precipitation technique and double emulsion-solvent evaporation,respectively.After characterizing physicochemical properties and drug release kinetics,they were dispersed in sodium hyaluronate solution for IT injection,then in vivo pharmacokinetics and biocompatibility in guinea pigs were studied.Results:DEX MCs exhibited stable dissolution,while LPNMs provided sustained lidocaine release,reducing potential side effects.In vivo studies in guinea pigs demonstrated prolonged drug retention in the perilymph and improved pharmacokinetics.Histological evaluation confirmed the good biocompatibility of this combined delivery system,with no significant inner ear damage observed.Conclusion:This co-delivery system can be used as a depot for delivering both DEX and lidocaine to the inner ear and offers a promising approach for the synergistic treatment of SSNHL associated with tinnitus.展开更多
Objective:To evaluate the plasma levels of the otoconial proteins,otoconin-90 and otolin-1,in individuals diagnosed with vestibular neuritis(VN)and determine the feasibility of using these proteins as biomarkers for V...Objective:To evaluate the plasma levels of the otoconial proteins,otoconin-90 and otolin-1,in individuals diagnosed with vestibular neuritis(VN)and determine the feasibility of using these proteins as biomarkers for VN.Methods:In this preliminary study,30 patients diagnosed with VN and 70 healthy individuals were recruited and followed to confirm whether they had benign paroxysmal positional vertigo(BPPV)during the following time.The recorded data included measurements of height,weight,and history of diabetes mellitus or hypertension.Additionally,levels of plasma otoconin-90,and otolin-1 were measured and compared.Results:The plasma concentrations of otoconin-90 and otolin-1 may not be significantly different between patients with VN and healthy controls,nor among patients with BPPV secondary to VN and patients with VN without BPPV.Conclusions:Plasma otoconin-90 and otolin-1 levels may not serve as biomarkers of acute VN episodes or predict BPPV occurrence secondary to VN.展开更多
BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a...BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a common site for MS plaques,and the medial olivocochlear(MOC)system is located in the superior olivary complex(SOC)of the brainstem.The cochlear nuclei are also involved in the MOC reflex arc.Additionally,the temporal cortex can modulate the SOC and cochlear nucleus,so lesions in the brainstem or temporal cortex may affect the MOC reflex in MS.AIM To investigate efferent auditory system activity in patients with multiple sclerosis via the MOC reflex.METHODS The study included 50 patients with MS and 50 healthy controls.Patients with MS were divided into three subgroups according to cranial magnetic resonance imaging findings:Patients with brainstem lesions(Group 1,n=20);patients with temporal cortex lesions without brainstem involvement(Group 2,n=20);and patients without any lesions in the brainstem or temporal cortex(Group 3,n=10).Tympanometry,acoustic stapedial reflex thresholds,pure-tone audiometry,and transientevoked otoacoustic emission(TEOAE)tests(with and without contralateral noise)were performed for all participants.RESULTS There was no significant difference in pure-tone hearing thresholds or baseline TEOAE amplitudes between the MS and control groups,indicating normal cochlear function in patients with MS;however,MOC reflex suppression was significantly reduced in patients with MS compared to controls(P=0.021).In particular,Group 1(MS with brainstem lesions)showed the lowest mean suppression values,which was significantly lower than that of Group 2 and the control group(P=0.002).By contrast,Group 2 and Group 3 did not significantly differ from controls.Additionally,patients with MS exhibited a sex difference in MOC function:Male patients had significantly lower suppression compared to female patients both within Group 1 and in the MS group as a whole.CONCLUSION The findings indicate that the efferent auditory system(specifically the MOC reflex)is affected by MS.MOC reflex activity was most significantly decreased in patients with MS with brainstem lesions,while temporal cortex lesions alone did not appear to notably impair the MOC reflex.Diminished MOC activity may underlie various auditory difficulties in patients with MS(e.g.,hearing in noise),and loss of efferent suppression could contribute to symptoms such as hyperacusis or tinnitus in this population.Further studies are needed to better understand the relationship between MOC dysfunction and auditory symptoms in MS,as well as the potential diagnostic value of MOC testing in MS.展开更多
The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells.Unlike the regenerative capacity found in various other cells throughout the body,cochlear sensory ce...The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells.Unlike the regenerative capacity found in various other cells throughout the body,cochlear sensory cells lack the ability to regenerate once damaged.Furthermore,a decline in the quantity of these cells results in a deterioration of auditory function.Piezoelectric materials can generate electric charge in response to sound wave vibration,making them theoretically suitable for replacing hair cell function.This study explores an innovative approach using piezoelectric nanocomposite filaments,namely poly(vinylidene fluoride),poly(vinylidene fluoride)/barium titanate,and poly(vinylidene fluoride)/reduced graphene oxide,as self-powered acoustic sensors designed to function in place of cochlear hair cells.These flexible filaments demonstrate a unique ability to generate electricity in response to frequency sounds from 50 up to 1000 Hz at moderate sound pressure levels(60–95 dB),approaching the audible range with an overall acoustoelectric energy conversion efficiency of 3.25%.Serving as self-powered acoustic sensors,these flexible filaments hold promise for potential applications in cochlear implants,with a high sensitivity of 117.5 mV(Pa-cm^(2))^(-1).The cytocompatibility of these filaments was assessed through in vitro viability tests conducted on three cell lines,serving as a model for inner ear cells.展开更多
Objective:To describe the characteristics of the clinical presentation,diagnosis,surgical methods,and outcomes of patients with otogenic cerebrospinal fluid(CSF)leakage secondary to congenital inner ear dysplasia.Meth...Objective:To describe the characteristics of the clinical presentation,diagnosis,surgical methods,and outcomes of patients with otogenic cerebrospinal fluid(CSF)leakage secondary to congenital inner ear dysplasia.Methods:A retrospective review was performed of 18 patients with otogenic CSF leakage secondary to inner ear dysplasia who underwent surgery in our group from 2007 to 2017 and had a follow-up of at least 4 months.The average length of follow-up was three years.The characteristics of the clinical presentations of all patients,such as self-reported symptoms,radiographic findings,surgical approaches and methods of repair,position of the leakage during surgery,and postoperative course,including the success rate of surgery,are presented.Results:The patients presented mostly with typical symptoms of meningitis,severe hearing impairment,and CSF otorrhea or rhinorrhea.All 18 patients had at least one previous episode of meningitis accompanied by a severe hearing impairment.The preoperative audiograms of 17 patients showed profound sensorineural hearing loss,and one patient had conductive hearing loss.Twelve patients presented with an initial onset of otorrhea,and two had accompanying rhinorrhea.Six patients complained of rhinorrhea,two of whom were misdiagnosed with CSF rhinorrhea and underwent transnasal endoscopy at another hospital.High-resolution computed tomography(HRCT)images can reveal developments in the inner ear,such as expansion of a vestibular cyst,unclear structure of the semicircular canal or cochlea,or signs of effusion in the middle ear or mastoid,which strongly suggest the possibility of CSF otorrhea.The children in the study suffered more severe dysplasia than adults.All 18 patients had CSF leakage identified during surgery.The most common defect sites were in the stapes footplates(55.6%),and 38.9%of patients had a leak around the oval window.One patient had a return of CSF otorrhea during the postoperative period,which did not re-occur following a second repair.Conclusions:CSF otorrhea due to congenital inner ear dysplasia is more severe in children than in adults.The most common symptoms were meningitis,hearing impairment,and CSF otorrhea or rhinorrhea.HRCT has high diagnostic accuracy for this disease.The most common fistula site was around the oval window,including the stapes footplates and the annular ligament.展开更多
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...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.展开更多
Bone morphogenetic proteins(BMPs)are the largest subfamily of the transforming growth factor-βsuperfamily,and they play important roles in the development of numerous organs,including the inner ear.The inner ear is a...Bone morphogenetic proteins(BMPs)are the largest subfamily of the transforming growth factor-βsuperfamily,and they play important roles in the development of numerous organs,including the inner ear.The inner ear is a relatively small organ but has a highly complex structure and is involved in both hearing and balance.Here,we discuss BMPs and BMP signaling pathways and then focus on the role of BMP signal pathway regulation in the development of the inner ear and the implications this has for the treatment of human hearing loss and balance dysfunction.展开更多
Auditory function in vertebrates depends on the transduction of sound vibrations into electrical signals by inner ear hair cells.In general,hearing loss resulting from hair cell damage is irreversible because the huma...Auditory function in vertebrates depends on the transduction of sound vibrations into electrical signals by inner ear hair cells.In general,hearing loss resulting from hair cell damage is irreversible because the human ear has been considered to be incapable of regenerating or repairing these sensory elements following severe injury.Therefore,regeneration and protection of inner ear hair cells have become an exciting,rapidly evolving field of research during the last decade.However,mammalian auditory hair cells are few in number,experimentally inaccessible,and barely proliferate postnatally in vitro.Various in vitro primary culture systems of inner ear hair cells have been established by different groups,although many challenges remain unresolved.Here,we briefly explain the structure of the inner ear,summarize the published methods of in vitro hair cell cultures,and propose a feasible protocol for culturing these cells,which gave satisfactory results in our study.A better understanding of in vitro hair cell cultures will substantially facilitate research involving auditory functions,drug development,and the isolation of critical molecules involved in hair cell biology.展开更多
In this study,I focused on finding a mean of protecting against hearing loss.By infusing the cochlea with the neurotrophin factor,NT-3 alone or combined treatment with MK 801,a NMDA receptor antagonist I found hearing...In this study,I focused on finding a mean of protecting against hearing loss.By infusing the cochlea with the neurotrophin factor,NT-3 alone or combined treatment with MK 801,a NMDA receptor antagonist I found hearing loss was attenuated and spiral ganglion neuron loss was nearly totally protected indicating that the importance of the combined treatment of NT-3 and NMDA receptor antagonists in the treatment of hearing disorders.展开更多
K^(+)cycling in the cochlea is critical to maintain hearing.Many sodium-potassium pumps are proved to participate in K^(+)cycling,such as Na/K-ATPase.Theα2-Na/K-ATPase is an important isoform of Na/K-ATPase.The expre...K^(+)cycling in the cochlea is critical to maintain hearing.Many sodium-potassium pumps are proved to participate in K^(+)cycling,such as Na/K-ATPase.Theα2-Na/K-ATPase is an important isoform of Na/K-ATPase.The expression ofα2-Na/K-ATPase in the cochlea is not clear.In this study,we used C57BL/6 mice as a model of presbycusis and implemented immunohistochemistry staining and quantitative real time-PCR,and theα2-Na/K-ATPase expression pattern was confirmed in the inner ear.It was foundα2-Na/K-ATPase was expressed widely in cochlea and its mRNA and protein expression was gradually reduced with aging(4-,14-,26-and 48-weeks old mice).We suspected that,the down-regulation ofα2-Na/K-ATPase expression might be associated with the remodeling of K^(+)cycling,degeneration of morphological structure and decrease of hearing function in aging C57 mice.In conclusion,we speculated that the reduction ofα2-Na/K-ATPase might play an important role in the pathogenesis of age-related hearing loss.展开更多
Congenital hearing loss is a common disorder worldwide.Heterogeneous gene variation accounts for approximately 20-25%of such patients.We investigated a five-generation Chinese family with autosomaldominant nonsyndromi...Congenital hearing loss is a common disorder worldwide.Heterogeneous gene variation accounts for approximately 20-25%of such patients.We investigated a five-generation Chinese family with autosomaldominant nonsyndromic sensorineural hearing loss(SNHL).No wave was detected in the pure-tone audiometry,and the auditory brainstem response was absent in all patients.Computed tomography of the patients,as well as of two sporadic SNHL cases,showed bilateral inner ear anomaly,cochlear maldevelopment,absence of the osseous spiral lamina,and an enlarged vestibular aqueduct.Such findings were absent in nonaffected persons.We used linkage analysis and exome sequencing and uncovered a heterozygous missense mutation in the PI4 KB gene(p.Gln121 Arg)encoding phosphatidylinositol 4-kinaseβ(PI4 KB)from the patients in this family.In addition,3 missense PI4 KB(p.Val434 Gly,p.Glu667 Lys,and p.Met739 Arg)mutations were identified in five patients with nonsyndromic SNHL from 57 sporadic cases.No such mutations were present within 600 Chinese controls,the 1000 genome project,gnom AD,or similar databases.Depleting pi4 kb m RNA expression in zebrafish caused inner ear abnormalities and audiosensory impairment,mimicking the patient phenotypes.Moreover,overexpression of 4 human missense PI4 KB mutant m RNAs in zebrafish embryos resulted in impaired hearing function,suggesting dominant-negative effects.Taken together,our results reveal that PI4 KB mutations can cause SNHL and inner ear malformation.PI4 KB should be included in neonatal deafness screening.展开更多
Postaurical injection of therapeutics was recently applied in clinical practice to treat inner ear diseases based on supposed existence of a direct channel from the postaurical area to the inner ear. Doubting on the a...Postaurical injection of therapeutics was recently applied in clinical practice to treat inner ear diseases based on supposed existence of a direct channel from the postaurical area to the inner ear. Doubting on the associated reports and aiming to provide evidence on the inner ear uptake mechanism, the present study tracked the dynamic distribution of gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (Gd-DOTA) in rat inner ears after postaurical injection using MRI. A targeted tympanic medial wall delivery was utilized as control. The results showed that, at the early time points after postaurical injection, Gd-DOTA distributed mainly in tissues surrounding the bulla, temporal bone and skull and neck space. In the inner ear, there was gradual uptake of Gd-DOTA on both the ipsilateral and contralateral sides with equal signal intensities. There was no sign of direct channel carrying the agent from the postaurical area to the inner ear. Targeted tympanic medial wall delivery induced significantly greater uptake of Gd-DOTA in the inner ear than did postaurical injection. At 30 min post-administration, targeted tympanic medial wall delivery yielded 4.6-folds higher signal intensity than did postaurical injection. The total dose of Gd-DOTA delivered by the targeted tympanic medial wall approach was only 0.1% of that delivered by postaurical injection. In conclusion, postaurical injection is a systemic administration, which is similar to hypodermic injection, rather than a focal delivery method. By contraries, targeted tympanic medial wall delivery induces fast and abundant uptake of Gd-DOTA in the ipsilateral inner ear without significant distribution in unwanted areas.展开更多
Columnar outer hair cells of the inner ear form V-shaped bundles, which are arranged in three rows in the cochlea. If the formation of these V-shaped bundles is disturbed, sensorineural hearing loss occurs. To quantif...Columnar outer hair cells of the inner ear form V-shaped bundles, which are arranged in three rows in the cochlea. If the formation of these V-shaped bundles is disturbed, sensorineural hearing loss occurs. To quantify the distribution of V-shaped bundles, the use of a Turing-type reaction-diffusion (RD) system, including anisotropic diffusion, should be considered. We found that a periodic triangle pattern appears based on the anisotropy in the RD system. Then, using the proposed RD system, the image of the V-shaped bundle was examined. The results showed that the correlation between the RD pattern and V-shape bundles not only classifies the experimental result but also significantly differs in the number of directional changes in a set of V-shape bundle. Therefore, this process can help quantify the images of V-shaped bundles.展开更多
Hair cells in the mammalian inner ear are very fragile and are often injured as a result of acoustic trauma or exposure to ototoxic drugs (cisplatin, aminoglycosides, etc) [1]. In amphibians and birds, spontaneous
Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and e...Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.展开更多
Hearing loss and deafness,as a worldwide disability disease,have been troubling human beings.However,the auditory organ of the inner ear is highly heterogeneous and has a very limited number of cells,which are largely...Hearing loss and deafness,as a worldwide disability disease,have been troubling human beings.However,the auditory organ of the inner ear is highly heterogeneous and has a very limited number of cells,which are largely uncharacterized in depth.Recently,with the development and utilization of single-cell RNA sequencing(scRNA-seq),researchers have been able to unveil the complex and sophisticated biological mechanisms of various types of cells in the auditory organ at the single-cell level and address the challenges of cellular heterogeneity that are not resolved through by conventional bulk RNA sequencing(bulk RNAseq).Herein,we reviewed the application of scRNA-seq technology in auditory research,with the aim of providing a reference for the development of auditory organs,the pathogenesis of hearing loss,and regenerative therapy.Prospects about spatial transcriptomic scRNA-seq,single-cell based genome,and Live-seq technology will also be discussed.展开更多
Hair cells in the mammalian cochlea are highly vulnerable to damage from drug toxicity,noise exposure,aging,and genetic mutations,with no capacity for regeneration.Progress in hair cell protection research has been li...Hair cells in the mammalian cochlea are highly vulnerable to damage from drug toxicity,noise exposure,aging,and genetic mutations,with no capacity for regeneration.Progress in hair cell protection research has been limited by the scarcity of cochlear tissue and suitable in vitro models.Here,we present a novel one-step,self-organizing inner ear organoid system optimized with small molecules,which bypasses the need for multi-step expansion and forced differentiation protocols.This approach efficiently generates hair cells and supporting cells that recapitulate the molecular,cellular,and structural characteristics of the inner ear.Single-cell RNA sequencing revealed the diversity and fidelity of cell populations within the organoids.Utilizing this platform,we validated the protective effects of candidate compounds against hair cell damage,highlighting its potential as a powerful tool for drug discovery and mechanistic studies of hair cell protection.展开更多
基金supported by the National Key Research and Development Program of China(grant no.2022YFC2402705)National Municipal Natural Science Foundation(grant no.82471161)Beijing Municipal Natural Science Foundation(grant no.7244308)。
文摘Objective:The aims of this study were to investigate the clinical applicability of 3D segmentation in measuring cochlear anatomical parameters,explore factors that influence the insertion angle of cochlear implant electrodes in patients with inner ear malformations,and determine the value of 3D segmentation in predicting cochlear implant electrode insertion depth by simulating electrode implantation in a reconstructed 3D model.Methods:Data from 208 temporal bone CT scans of patients with a variety of inner ear malformations(including the CH,IP-Ⅰ,IP-Ⅱ,and IP-Ⅲtypes)who underwent cochlear implantation at our center were retrospectively analyzed.Preoperative temporal bone CT data were subjected to three-dimensional(3D)segmentation of the cochlea with a 3D slicer.Results:Cochlear malformation types,including IP typesⅠ(42 ears),Ⅱ(278ears),Ⅲ(20 ears),and CH(65 ears),were diagnosed and measured in 208 preoperative CT datasets.Cochlear anatomical parameters and electrode length were correlated,which partially explained the variations in electrode insertion angle.The mean angle of implantation among the enrolled patients was 564.33°,and the mean implantation angle prediction error in the 3D segmentation was|23.74|°.Conclusion:Three-dimensional segmentation from temporal bone CT is valuable for surgeons,especially in treating patients with inner ear malformation.Such insights will help surgeons understand overall anatomical variations,predict electrode implantation depth,and complete preoperative imaging assessments for cochlear implant insertion depth in patients with inner ear malformations.
基金supported by Capital’s Funds for Health Improvement and Research(CFH:2022-2-5072)the Tianjin Natural Science Foundation for Jingjinji Collaboration(23JCZXJC00240)+1 种基金Beijing Natural Science Foundation(J230006)the CAMS Innovation Fund for Medical Science(2021-I2M-1-052).
文摘ObjectiveTo develop a sustained-release codelivery system for intratympanic administration of dexamethasone(DEX)and lipoic acid(LA).MethodsDEX microcrystals(MCs)were prepared via precipitation,while LA-loaded porous PLGA microspheres(LPMPs)were fabricated using a double emulsion–solvent evaporation method.DEX MCs were physically perfused into LPMPs via negative pressure to form a combined system(DEX MCs+LPMPs).Physicochemical properties,in vitro drug release,pharmacokinetics,and biocompatibility were evaluated.Guinea pigs were used for intratympanic injections of DEX MCs,LPMPs,or DEX MCs+LPMPs.ResultsThe DEX MCs+LPMPs system enabled simultaneous release of both drugs,with DEX exhibiting superior pharmacokinetics(sustained perilymph concentrations up to 7 days)compared to DEX MCs alone.LA release from LPMPs demonstrated prolonged kinetics without burst release.SEM confirmed DEX MCs were localized within/on LPMPs and adhered to the round window membrane(RWM).Histological analysis revealed normal cochlear morphology and no inflammatory response,confirming biocompatibility.ConclusionsThis novel codelivery system combining microcrystals and porous microspheres achieves sustained dual-drug release,enhances therapeutic efficacy,and offers a promising strategy for managing hearing loss via intratympanic administration.
基金Tianjin Natural Science Foundation for Jingjinji Collaboration,Grant/Award Number:23JCZXJC00240Hebei Natural Science Foundation,Grant/Award Number:H2023201903+2 种基金Beijing Natural Science Foundation,Grant/Award Number:J230006Capital's Funds for Health Improvement and Research,Grant/Award Number:CFH:2022-2-5072CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2021-I2M-1-052。
文摘Background:Sudden sensorineural hearing loss(SSNHL),often associated with tinnitus,significantly impacts individuals'quality of life.Current treatments,such as free drugs via intravenous or intratympanic(IT)administration of dexamethasone(DEX)and lidocaine,face limitations like low bioavailability and rapid drug clearance.To address these challenges,we developed a local co-delivery system combining DEX microcrystals(DEX MCs)and lidocaine-loaded poly(lactic-co-glycolic acid)(PLGA)non-spherical microparticles(LPNMs)for sustained drug release in the inner ear.Methods:DEX MCs and LPNMs were prepared using the traditional precipitation technique and double emulsion-solvent evaporation,respectively.After characterizing physicochemical properties and drug release kinetics,they were dispersed in sodium hyaluronate solution for IT injection,then in vivo pharmacokinetics and biocompatibility in guinea pigs were studied.Results:DEX MCs exhibited stable dissolution,while LPNMs provided sustained lidocaine release,reducing potential side effects.In vivo studies in guinea pigs demonstrated prolonged drug retention in the perilymph and improved pharmacokinetics.Histological evaluation confirmed the good biocompatibility of this combined delivery system,with no significant inner ear damage observed.Conclusion:This co-delivery system can be used as a depot for delivering both DEX and lidocaine to the inner ear and offers a promising approach for the synergistic treatment of SSNHL associated with tinnitus.
基金supported by the Ningbo Leading Medical&Health Discipline(Grant No.2022-B12)Ningbo Natural Science Foundation(Grant No.202003N4240)+1 种基金Hwa Mei Foundation(Grant No.2021HMZY102,Grant No.2022HMKY45)Medical Scientific Research Foundation of Zhejiang Province(Grant No.2023KY1085).
文摘Objective:To evaluate the plasma levels of the otoconial proteins,otoconin-90 and otolin-1,in individuals diagnosed with vestibular neuritis(VN)and determine the feasibility of using these proteins as biomarkers for VN.Methods:In this preliminary study,30 patients diagnosed with VN and 70 healthy individuals were recruited and followed to confirm whether they had benign paroxysmal positional vertigo(BPPV)during the following time.The recorded data included measurements of height,weight,and history of diabetes mellitus or hypertension.Additionally,levels of plasma otoconin-90,and otolin-1 were measured and compared.Results:The plasma concentrations of otoconin-90 and otolin-1 may not be significantly different between patients with VN and healthy controls,nor among patients with BPPV secondary to VN and patients with VN without BPPV.Conclusions:Plasma otoconin-90 and otolin-1 levels may not serve as biomarkers of acute VN episodes or predict BPPV occurrence secondary to VN.
文摘BACKGROUND Multiple sclerosis(MS)is known to affect many sensory systems,yet most auditory research in MS has focused on the afferent pathways,with relatively few studies examining efferent function.The brainstem is a common site for MS plaques,and the medial olivocochlear(MOC)system is located in the superior olivary complex(SOC)of the brainstem.The cochlear nuclei are also involved in the MOC reflex arc.Additionally,the temporal cortex can modulate the SOC and cochlear nucleus,so lesions in the brainstem or temporal cortex may affect the MOC reflex in MS.AIM To investigate efferent auditory system activity in patients with multiple sclerosis via the MOC reflex.METHODS The study included 50 patients with MS and 50 healthy controls.Patients with MS were divided into three subgroups according to cranial magnetic resonance imaging findings:Patients with brainstem lesions(Group 1,n=20);patients with temporal cortex lesions without brainstem involvement(Group 2,n=20);and patients without any lesions in the brainstem or temporal cortex(Group 3,n=10).Tympanometry,acoustic stapedial reflex thresholds,pure-tone audiometry,and transientevoked otoacoustic emission(TEOAE)tests(with and without contralateral noise)were performed for all participants.RESULTS There was no significant difference in pure-tone hearing thresholds or baseline TEOAE amplitudes between the MS and control groups,indicating normal cochlear function in patients with MS;however,MOC reflex suppression was significantly reduced in patients with MS compared to controls(P=0.021).In particular,Group 1(MS with brainstem lesions)showed the lowest mean suppression values,which was significantly lower than that of Group 2 and the control group(P=0.002).By contrast,Group 2 and Group 3 did not significantly differ from controls.Additionally,patients with MS exhibited a sex difference in MOC function:Male patients had significantly lower suppression compared to female patients both within Group 1 and in the MS group as a whole.CONCLUSION The findings indicate that the efferent auditory system(specifically the MOC reflex)is affected by MS.MOC reflex activity was most significantly decreased in patients with MS with brainstem lesions,while temporal cortex lesions alone did not appear to notably impair the MOC reflex.Diminished MOC activity may underlie various auditory difficulties in patients with MS(e.g.,hearing in noise),and loss of efferent suppression could contribute to symptoms such as hyperacusis or tinnitus in this population.Further studies are needed to better understand the relationship between MOC dysfunction and auditory symptoms in MS,as well as the potential diagnostic value of MOC testing in MS.
基金financial support received from Deakin University through the Alfred Deakin Postdoctoral Research Fellowship(2022)partially funded by the European Union–Next-Generation EU via the Italian Ministry of University and Research(MUR),PRIN 2022 Program(PROMISE project,CUP 153D23004700006)+1 种基金support from the Australian National Fabrication Facility(ANFF)the ARC Research Hub for Future Fibres.
文摘The conversion of sound vibration into electrical potential is a critical function performed by cochlear hair cells.Unlike the regenerative capacity found in various other cells throughout the body,cochlear sensory cells lack the ability to regenerate once damaged.Furthermore,a decline in the quantity of these cells results in a deterioration of auditory function.Piezoelectric materials can generate electric charge in response to sound wave vibration,making them theoretically suitable for replacing hair cell function.This study explores an innovative approach using piezoelectric nanocomposite filaments,namely poly(vinylidene fluoride),poly(vinylidene fluoride)/barium titanate,and poly(vinylidene fluoride)/reduced graphene oxide,as self-powered acoustic sensors designed to function in place of cochlear hair cells.These flexible filaments demonstrate a unique ability to generate electricity in response to frequency sounds from 50 up to 1000 Hz at moderate sound pressure levels(60–95 dB),approaching the audible range with an overall acoustoelectric energy conversion efficiency of 3.25%.Serving as self-powered acoustic sensors,these flexible filaments hold promise for potential applications in cochlear implants,with a high sensitivity of 117.5 mV(Pa-cm^(2))^(-1).The cytocompatibility of these filaments was assessed through in vitro viability tests conducted on three cell lines,serving as a model for inner ear cells.
基金Project supported by the National Natural Science Foundation of China(Nos.81570914 and 81700925)
文摘Objective:To describe the characteristics of the clinical presentation,diagnosis,surgical methods,and outcomes of patients with otogenic cerebrospinal fluid(CSF)leakage secondary to congenital inner ear dysplasia.Methods:A retrospective review was performed of 18 patients with otogenic CSF leakage secondary to inner ear dysplasia who underwent surgery in our group from 2007 to 2017 and had a follow-up of at least 4 months.The average length of follow-up was three years.The characteristics of the clinical presentations of all patients,such as self-reported symptoms,radiographic findings,surgical approaches and methods of repair,position of the leakage during surgery,and postoperative course,including the success rate of surgery,are presented.Results:The patients presented mostly with typical symptoms of meningitis,severe hearing impairment,and CSF otorrhea or rhinorrhea.All 18 patients had at least one previous episode of meningitis accompanied by a severe hearing impairment.The preoperative audiograms of 17 patients showed profound sensorineural hearing loss,and one patient had conductive hearing loss.Twelve patients presented with an initial onset of otorrhea,and two had accompanying rhinorrhea.Six patients complained of rhinorrhea,two of whom were misdiagnosed with CSF rhinorrhea and underwent transnasal endoscopy at another hospital.High-resolution computed tomography(HRCT)images can reveal developments in the inner ear,such as expansion of a vestibular cyst,unclear structure of the semicircular canal or cochlea,or signs of effusion in the middle ear or mastoid,which strongly suggest the possibility of CSF otorrhea.The children in the study suffered more severe dysplasia than adults.All 18 patients had CSF leakage identified during surgery.The most common defect sites were in the stapes footplates(55.6%),and 38.9%of patients had a leak around the oval window.One patient had a return of CSF otorrhea during the postoperative period,which did not re-occur following a second repair.Conclusions:CSF otorrhea due to congenital inner ear dysplasia is more severe in children than in adults.The most common symptoms were meningitis,hearing impairment,and CSF otorrhea or rhinorrhea.HRCT has high diagnostic accuracy for this disease.The most common fistula site was around the oval window,including the stapes footplates and the annular ligament.
基金supported by the National Natural Science Foundation of China(grant number:81170914/H1304)
文摘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.
基金Project Project supported by the National Key Technologies R&D Program of China(Nos.2017YFA0103900 and 2016YFC0905200)the National Natural Science Foundation of China(Nos.81620108005,8177040802,and 81622013)the Shanghaigng Talents Plan(No.18PJ1401700),China
文摘Bone morphogenetic proteins(BMPs)are the largest subfamily of the transforming growth factor-βsuperfamily,and they play important roles in the development of numerous organs,including the inner ear.The inner ear is a relatively small organ but has a highly complex structure and is involved in both hearing and balance.Here,we discuss BMPs and BMP signaling pathways and then focus on the role of BMP signal pathway regulation in the development of the inner ear and the implications this has for the treatment of human hearing loss and balance dysfunction.
基金Project supported by the National Basic Research Priorities Program of China(Nos.2014CB541702 and 2014CB541704)the National Natural Science Foundation of China(No.31671305)
文摘Auditory function in vertebrates depends on the transduction of sound vibrations into electrical signals by inner ear hair cells.In general,hearing loss resulting from hair cell damage is irreversible because the human ear has been considered to be incapable of regenerating or repairing these sensory elements following severe injury.Therefore,regeneration and protection of inner ear hair cells have become an exciting,rapidly evolving field of research during the last decade.However,mammalian auditory hair cells are few in number,experimentally inaccessible,and barely proliferate postnatally in vitro.Various in vitro primary culture systems of inner ear hair cells have been established by different groups,although many challenges remain unresolved.Here,we briefly explain the structure of the inner ear,summarize the published methods of in vitro hair cell cultures,and propose a feasible protocol for culturing these cells,which gave satisfactory results in our study.A better understanding of in vitro hair cell cultures will substantially facilitate research involving auditory functions,drug development,and the isolation of critical molecules involved in hair cell biology.
文摘In this study,I focused on finding a mean of protecting against hearing loss.By infusing the cochlea with the neurotrophin factor,NT-3 alone or combined treatment with MK 801,a NMDA receptor antagonist I found hearing loss was attenuated and spiral ganglion neuron loss was nearly totally protected indicating that the importance of the combined treatment of NT-3 and NMDA receptor antagonists in the treatment of hearing disorders.
基金National Natural Science Foundation of China(Nos.81771004,81271078,81500791,81500794 and 81300827).
文摘K^(+)cycling in the cochlea is critical to maintain hearing.Many sodium-potassium pumps are proved to participate in K^(+)cycling,such as Na/K-ATPase.Theα2-Na/K-ATPase is an important isoform of Na/K-ATPase.The expression ofα2-Na/K-ATPase in the cochlea is not clear.In this study,we used C57BL/6 mice as a model of presbycusis and implemented immunohistochemistry staining and quantitative real time-PCR,and theα2-Na/K-ATPase expression pattern was confirmed in the inner ear.It was foundα2-Na/K-ATPase was expressed widely in cochlea and its mRNA and protein expression was gradually reduced with aging(4-,14-,26-and 48-weeks old mice).We suspected that,the down-regulation ofα2-Na/K-ATPase expression might be associated with the remodeling of K^(+)cycling,degeneration of morphological structure and decrease of hearing function in aging C57 mice.In conclusion,we speculated that the reduction ofα2-Na/K-ATPase might play an important role in the pathogenesis of age-related hearing loss.
基金supported by the grants from the National Key R&D Program of China(2018YFA0801200)the National Natural Science Foundation of China(31970777,31771628,and 31601165)+1 种基金Guangdong Natural Science Fund for Distinguished Young Scholars(2017A030306024)to J.Z.the Deutsche Forschungsgemeinschaft(DFG:GO 1990/1-1)to M.G
文摘Congenital hearing loss is a common disorder worldwide.Heterogeneous gene variation accounts for approximately 20-25%of such patients.We investigated a five-generation Chinese family with autosomaldominant nonsyndromic sensorineural hearing loss(SNHL).No wave was detected in the pure-tone audiometry,and the auditory brainstem response was absent in all patients.Computed tomography of the patients,as well as of two sporadic SNHL cases,showed bilateral inner ear anomaly,cochlear maldevelopment,absence of the osseous spiral lamina,and an enlarged vestibular aqueduct.Such findings were absent in nonaffected persons.We used linkage analysis and exome sequencing and uncovered a heterozygous missense mutation in the PI4 KB gene(p.Gln121 Arg)encoding phosphatidylinositol 4-kinaseβ(PI4 KB)from the patients in this family.In addition,3 missense PI4 KB(p.Val434 Gly,p.Glu667 Lys,and p.Met739 Arg)mutations were identified in five patients with nonsyndromic SNHL from 57 sporadic cases.No such mutations were present within 600 Chinese controls,the 1000 genome project,gnom AD,or similar databases.Depleting pi4 kb m RNA expression in zebrafish caused inner ear abnormalities and audiosensory impairment,mimicking the patient phenotypes.Moreover,overexpression of 4 human missense PI4 KB mutant m RNAs in zebrafish embryos resulted in impaired hearing function,suggesting dominant-negative effects.Taken together,our results reveal that PI4 KB mutations can cause SNHL and inner ear malformation.PI4 KB should be included in neonatal deafness screening.
基金supported by the 1255 project of Changhai HospitalSecond Military Medical University,Shanghai,China
文摘Postaurical injection of therapeutics was recently applied in clinical practice to treat inner ear diseases based on supposed existence of a direct channel from the postaurical area to the inner ear. Doubting on the associated reports and aiming to provide evidence on the inner ear uptake mechanism, the present study tracked the dynamic distribution of gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (Gd-DOTA) in rat inner ears after postaurical injection using MRI. A targeted tympanic medial wall delivery was utilized as control. The results showed that, at the early time points after postaurical injection, Gd-DOTA distributed mainly in tissues surrounding the bulla, temporal bone and skull and neck space. In the inner ear, there was gradual uptake of Gd-DOTA on both the ipsilateral and contralateral sides with equal signal intensities. There was no sign of direct channel carrying the agent from the postaurical area to the inner ear. Targeted tympanic medial wall delivery induced significantly greater uptake of Gd-DOTA in the inner ear than did postaurical injection. At 30 min post-administration, targeted tympanic medial wall delivery yielded 4.6-folds higher signal intensity than did postaurical injection. The total dose of Gd-DOTA delivered by the targeted tympanic medial wall approach was only 0.1% of that delivered by postaurical injection. In conclusion, postaurical injection is a systemic administration, which is similar to hypodermic injection, rather than a focal delivery method. By contraries, targeted tympanic medial wall delivery induces fast and abundant uptake of Gd-DOTA in the ipsilateral inner ear without significant distribution in unwanted areas.
文摘Columnar outer hair cells of the inner ear form V-shaped bundles, which are arranged in three rows in the cochlea. If the formation of these V-shaped bundles is disturbed, sensorineural hearing loss occurs. To quantify the distribution of V-shaped bundles, the use of a Turing-type reaction-diffusion (RD) system, including anisotropic diffusion, should be considered. We found that a periodic triangle pattern appears based on the anisotropy in the RD system. Then, using the proposed RD system, the image of the V-shaped bundle was examined. The results showed that the correlation between the RD pattern and V-shape bundles not only classifies the experimental result but also significantly differs in the number of directional changes in a set of V-shape bundle. Therefore, this process can help quantify the images of V-shaped bundles.
基金supported by the follow grants:1. The StateKey Program of National Natural Science of China (Grant No. 30730040)2. The National High Technology Research and Development Program of China (Grant No.2007AA02Z150)+2 种基金3. The National Natural Science Foundation of China (30871398)Key Projects in the National Science & Technology Supporting Program during the Eleventh Five-Year Plan Period (2008BAI50B08 2007 BAI18B12, 2007BAI18B14)
文摘Hair cells in the mammalian inner ear are very fragile and are often injured as a result of acoustic trauma or exposure to ototoxic drugs (cisplatin, aminoglycosides, etc) [1]. In amphibians and birds, spontaneous
基金supported by the National Key Research and Development Program of China (2021YFA0805902,2022YFF0710703)National Natural Science Foundation of China (32201257)+1 种基金Science and Technology Innovation Project of Xiongan New Area (2022XAGG0121)Young Elite Scientists Sponsorship Program by the China Association for Science and Technology (2019QNRC001)。
文摘Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.
基金supported by grants from National Key R&D Program of China(2021YFA1101300,2021YFA1101800,2020YFA0112503)Strategic Priority Research Program of the Chinese Academy of Science(XDA16010303)+3 种基金National Natural Science Foundation of China(82030029,81970882,and 92149304)Science and Technology Department of Sichuan Province(2021YFS0371)Shenzhen Fundamental Research Program(JCYJ20190814093401920,JCYJ20210324125608022)Open Research Fund of State Key Laboratory of Genetic Engineering,Fudan University(SKLGE-2104).
文摘Hearing loss and deafness,as a worldwide disability disease,have been troubling human beings.However,the auditory organ of the inner ear is highly heterogeneous and has a very limited number of cells,which are largely uncharacterized in depth.Recently,with the development and utilization of single-cell RNA sequencing(scRNA-seq),researchers have been able to unveil the complex and sophisticated biological mechanisms of various types of cells in the auditory organ at the single-cell level and address the challenges of cellular heterogeneity that are not resolved through by conventional bulk RNA sequencing(bulk RNAseq).Herein,we reviewed the application of scRNA-seq technology in auditory research,with the aim of providing a reference for the development of auditory organs,the pathogenesis of hearing loss,and regenerative therapy.Prospects about spatial transcriptomic scRNA-seq,single-cell based genome,and Live-seq technology will also be discussed.
基金supported by the National Key R&D Program of China (2020YFA0112500, 2019YFA0110000)the National Natural Science Foundation of China (31970820)+2 种基金the Key Project of the Science and Technology of Shanghai Municipality (19JC1415300)the Fundamental Research Funds for the Central Universities (22120240435)Peak Disciplines (Type Ⅳ) of Institutions of Higher Learning in Shanghai
文摘Hair cells in the mammalian cochlea are highly vulnerable to damage from drug toxicity,noise exposure,aging,and genetic mutations,with no capacity for regeneration.Progress in hair cell protection research has been limited by the scarcity of cochlear tissue and suitable in vitro models.Here,we present a novel one-step,self-organizing inner ear organoid system optimized with small molecules,which bypasses the need for multi-step expansion and forced differentiation protocols.This approach efficiently generates hair cells and supporting cells that recapitulate the molecular,cellular,and structural characteristics of the inner ear.Single-cell RNA sequencing revealed the diversity and fidelity of cell populations within the organoids.Utilizing this platform,we validated the protective effects of candidate compounds against hair cell damage,highlighting its potential as a powerful tool for drug discovery and mechanistic studies of hair cell protection.
