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Cholesteatoma is an epidermal cyst with still unknown pathomechanism. The aim of the current study was to investigate molecular differences in the background of the hyperproliferative property and aggressive behavior typical of the cholesteatoma epithelium. The expression of three cytokeratin genes (KRT1, KRT10 and KRT19), the matrix metalloproteinase 9 gene (MMP9) and the tumor suppressor TP53 gene was measured by qRT-PCR in surgical samples of pediatric and adult cholesteatoma cases and their expression level was compared to that of normal skin samples from the retroauricular region of control individuals. Cholesteatoma samples were stratified according to the age of onset and recurrence for more detailed analysis. Our results showed identical expression pattern for KRT1 and KRT10, their expression was higher in pediatric cases than in adults, especially in pediatric recurrent samples. The expression level of KRT19 was inversely proportional to that of KRT1/KRT10, it was lower in the more invasive recurrent cases both in our pediatric and adult groups. As it was expected from the bone destructive behavior of cholesteatoma, a significantly elevated expression of MMP9 was measured in cholesteatoma samples, the highest level was found in adult recurrent cases. Low expression levels characterize the TP53 gene without significant differences in our samples. These findings demonstrate that cytokeratin expression distinguishes between pediatric/adult, nonrecurrent/recurrent cases, suggesting that distinct differentiation state and cell division potential characterize these cholesteatoma cases. KRT19 with a tumor suppressor potential might restrict the recurrence of cholesteatoma. The differences observed in gene expression profiles between cholesteatoma and control samples support the notion that cholesteatoma is a cystic lesion with tumor-like behavior because it is characterized by invasive, destructive growth and high tendency for recurrence.

This prospective case review was performed with the aim to compare and asses the diagnostic values of cone-beam computed tomography (CBCT) and high-resolution computed tomography (HRCT) in the preoperative evaluation of otosclerosis. A total of 43 patients with histologically confirmed stapedial otosclerosis, who underwent unilateral stapedectomies were analyzed. Preoperative temporal bone CBCT and HRCT scans were performed in all cases. Both CBCT and HRCT imaging were characterized by a slice thickness of 0.4-0.625 mm and multiplanar image reconstruction. Histopathologic examination of the removed stapes footplates was performed in all cases. Findings of CBCT and HRCT were categorized according to the modified Marshall's grading system (fenestral or retrofenestral lesions). Histopathologic results were correlated with multiplanar reconstructed CBCT and HRCT scans, respectively. Negative control groups for CBCT (n = 36) and HRCT (n = 27) examinations consisted of patients, who underwent CBCT imaging due to various dental disorders or HRCT analysis due to idiopathic sudden sensorineural hearing loss. Histologically active foci of otosclerosis (n = 31, 72 %) were identified by both CBCT and HRCT in all cases with a sensitivity of 100 %. However, CBCT could not detect histologically inactive otosclerosis (n = 12, 23 %; sensitivity 0 %). In contrast, HRCT showed inactive otosclerosis with a sensitivity of 59.3 %. According to CBCT results, no retrofenestral lesions were found and the overall sensitivity for hypodense lesions was 61.37 %. In conclusion, CBCT is a robust imaging method in the detection of histologically active fenestral hypodense foci of otosclerosis with high sensitivity and radiologic specificity. In the light of these results, HRCT still remains the basic imaging method in the preoperative diagnosis of otosclerosis, since it has much greater sensitivity and specificity in the detection of retrofenestral hypodense lesions and histologically inactive otosclerotic foci in the oval window niche.

OBJECTIVES To establish a mathematical model of middle ear gas pressure regulation and to discuss potential implications for pathophysiology-oriented theoretical approach to middle ear surgery, with particular attention to mastoid obliteration. BACKGROUND Numerous studies support that small mastoid volume is associated with cholesteatoma. Latest studies show that mastoid obliteration is an effective technique to lower the recurrence rate in these ears. METHODS A mathematical model was used to predict the development of gas pressure balance in the function of different middle ear volumes (VME), considering normal and dysfunctional Eustachian tube. Published data as gas pressure input values and our 3D CT reconstruction data in healthy and pathologic middle ears of children were applied. RESULTS The model predicted ≤6.66 daPa pressure fluctuations in VME ≥3 ml, compared to ≥16 daPa of a VME ≤1 ml at perfect ET function, because of the different pressure change rate and pressure buffer effect of the MEs. Substantially larger fluctuations can be expected in a VME

Cholesteatoma is an epidermoid cyst, which is most frequently found in the middle ear. The matrix of cholesteatoma is histologically similar to the matrix of the epidermoid cyst of the skin (atheroma); their epithelium is characterized by hyperproliferation. The c-MYC protooncogene located on chromosome 8q24 encodes a transcription factor involved in the regulation of cell proliferation and differentiation. Previous studies have found aneuploidy of chromosome 8, copy number variation of c-MYC gene, and the presence of elevated level c-MYC protein in cholesteatoma. In this study we have compared the expression of c-MYC gene in samples taken from the matrix of 26 acquired cholesteatomas (15 children and 11 adults), 15 epidermoid cysts of the skin (atheromas; head and neck region) and 5 normal skin samples (retroauricular region) using RT-qPCR, providing the first precise measurement of the expression of c-MYC gene in cholesteatoma. We have found significantly elevated c-MYC gene expression in cholesteatoma compared to atheroma and to normal skin samples. There was no significant difference, however, in c-MYC gene expression between cholesteatoma samples of children and adults. The significant difference in c-MYC gene expression level in cholesteatoma compared to that of atheroma implies a more prominent hyperproliferative phenotype which may explain the clinical behavior typical of cholesteatoma.

Microbial biofilms have been implicated in the pathogenesis of chronic rhinosinusitis with nasal polyposis (CRSwNP). Intranasal application of corticosteroids (INCS) is a reliable option in the management of CRSwNP. INCS medication has been suspected to influence the presence and thickness of microbial biofilms and inflammatory cell patterns in CRSwNP. Two series of identical nasal polyps obtained from non-allergic patients with CRSwNP (n = 56), who underwent endoscopic sinus surgery (ESS), were processed to hematoxylin–eosin (H.E.) and Gram staining, respectively. Patients were recruited into three groups. Group A (n = 21) consisted of patients with continuous preoperative INCS treatment. In group B (n = 17), patients were never treated by INCS, while in group C (n = 18) INCS medication was stopped at least 6 months before ESS. Biofilm positivity varied from 76.4 to 88.8 % in different subject groups. These values and average thickness of biofilms did not reach statistically significant levels (Mann–Whitney’s U probe, p > 0.05) in different patient groups. In contrast, microscopic pattern and numbers of predominant inflammatory cell populations displayed obvious differences according to INCS treatment (Mann–Whitney’s U probe, p < 0.001). According to these observations, INCS treatment does not affect the presence and thickness of microbial biofilms in CRSwNP. In contrast, it has significant effects on the pattern of inflammatory cells infiltrating the subepithelial layer, which might result in beneficially altered extracellular matrix production and cytokine release.

INTRODUCTION Recent studies have reported genetic associations between with single nucleotide polymorphism (SNP) of the several genes of the renin-angiotensin-aldosterone (RAA) system in otosclerosis without the confirmation of RAA system expression in human stapes footplates. There are conflicting results. These results are conflicting because RAA system expression has been attributed exclusively to neural, vascular, and renal tissues, exclusively. MATERIALS AND METHODS Ankylotic stapes footplates (n = 20), cortical bone fragments (n = 10), and human kidney tissue specimens (n = 10) were processed to hematoxylin-eosin (HE) staining and RAA system-specific immunofluorescent assay (IFA), respectively. RESULTS Histologic diagnosis of otosclerosis was established in all ankylotic stapes footplates. Histologically active- (n = 13) and inactive (n = 7) foci of otosclerosis were consequently characterized by negative immunoreactions for renin, angiotensin converting enzyme (ACE), angiotensin-II (AT-II), and angiotensin-II receptor (AT-IIR), consequently. In cortical bones, a considerable RAA system expression was observed confirmed in the perivascular bone marrow progenitor cells. Kidney specimens, applied as positive controls, showed intense RAA system-specific immunoreactions. CONCLUSION Concerning current observations, the 4 studied members of RAA system that did not display active expression were not expressed at protein level in otosclerotic stapes footplates. This phenomenon was independent from the histologic activity of otosclerosis. Between these conditions, the etiologic role of RAA system is questionable in the pathogenesis of otosclerosis.

Otosclerosis is a unique osseous remodeling disorder of the human temporal bone, which is also considered as a disease of measles virus-associated inflammatory-autoimmune reaction against the middle layer of the otic capsule: globuli interossei. Its preoperative diagnosis is rather difficult, and there is no consensus-based diagnostic protocol with enough high sensitivity and specificity for the clinical confirmation of the disease. On the other hand, the preoperative diagnosis or clinical diagnosis of otosclerosis was potentially important considering several differential diagnostic-, prognostic-, and legal-ethical factors and problems. At this time, combination of various well-defined and new preoperative diagnostic methods might serve a strong clinical suspicion for otosclerosis. This fact might provide the basis of diagnosis and helps to avoid unnecessary stapes surgeries, serious intraoperative complications, and “blinded surgeries”: explorative tympanostomies that are unacceptable for most of the patients with conductive hearing loss. In this chapter, an overview is provided about the potential preoperative diagnostic tools and their specificity and sensitivity levels in case of otosclerosis or non-otosclerotic stapes fixations. Finally, authors recommend a considerable preoperative diagnostic protocol for the confirmation or exclusion of otosclerosis.

The main goal of this report is to review our current knowledge about the etiopathogenesis of otosclerotic bone remodeling disorder focusing on measles virus infection. Otosclerosis is a disease of pathologically increased bone turnover of the human otic capsule; however, the etiopathogenesis remained unclear. Persisting measles virus infection, genetic predisposition, disturbed bone metabolism, inflammatory processes, autoimmunity, and hormonal and environmental factors also may play contributing roles in the pathogenesis of otosclerosis. In the future, prospective studies based on comprehensive histopathologic, molecular biologic, and genetic analysis are necessary to get further information about the background of disease in order to clarify the role of measles in the etiopathogenesis and to find the most promising treatment option.

To estimate the correlations between high-resolution computed tomography (HRCT) scans, preoperative audiometric findings and histopathologic results in stapes ankylosis.Retrospective case review.Tertiary referral center.A total of 57 patients with stapes ankylosis, who underwent unilateral stapedectomies were analyzed.Diagnostic and therapeutic.Preoperative HRCT examinations were performed in all cases. Findings of HRCT were categorized according to Marshall's grading system. Preoperative air-bone gaps (ABGs) and bone conduction (BC) thresholds were determined. Stapes footplates removed surgically were processed using hematoxylin and eosin staining.Active otosclerosis (n = 29) was demonstrated by HRCT with a sensitivity of 76.31%, whereas its sensitivity to establish inactive otosclerosis (n = 13, 61.9%) and nonotosclerotic stapes fixations (n = 15, 51.7%) was much lower. Nonotosclerotic stapes fixations were characterized by pure conductive hearing loss that was not associated with HRCT findings. HRCT grades showed statistically significant association with BC levels at the averages of 0.5-1-2 kHz frequencies in the group of ears with inactive otosclerosis, exclusively (p0.05).HRCT is a reliable imaging method in the preoperative diagnosis of different types of stapes fixations. Imaging findings should be evaluated together with clinical history and audiometric data for obtaining as precise diagnosis for stapes fixation as possible.

This study is the first to establish that bone morphogenetic protein 5 (BMP5) plays a role in the pathogenesis of otosclerosis. These results confirm that elevated expression levels of BMPs, members of the transforming growth factor (TGF)-β superfamily, contribute to the pathologically increased bone turnover in early, active stages of otosclerosis.Otosclerosis is a complex bone remodeling disorder of the otic capsule, which might be characterized by increased expression of different types of BMPs. TGF-β and BMP are both members of the TGF-β superfamily and play a critical role in bone resorption and new bone formation. It has been suggested that BMP and its receptors may be involved in the pathologically increased bone turnover observed in otosclerosis.Fifty-one otosclerotic and 16 non-otosclerotic ankylotic stapes footplates were histologically analyzed: conventional hematoxylin-eosin staining and BMP2, 4, 5, and 7specific immunofluorescent assays were performed. Cortical bone fragments (n = 35) and incus specimens (n = 6) were used as negative controls.Active otosclerosis (n = 39) was characterized by increased expression of BMP2, 4, 5, and 7. Inactive cases of otosclerosis (n = 12) were characterized by negative immunoreaction for BMPs. Non-otosclerotic stapes specimens (n = 16) and negative controls (n = 41) showed negligible BMP expression. The BMP expression pattern showed a strong correlation with the histological activity of otosclerosis.

Objectives/Hypothesis: Biofilms might play a potential role in the pathogenesis and high recurrence rate of chronic rhinosinusitis with nasal polyposis (CRSwNP). Biofilm persistence has been thought to correlate with epithelial damage, subepithelial inflammatory cell infiltration, and tumor necrosis factor-α receptor (TNFR) expression in CRSwNP. Study Design: Case-control experimental study. Methods: A total of 36 patients with CRSwNP undergoing endoscopic sinus surgery were analyzed. The negative control group consisted of eight patients undergoing septoplasty for nasal obstruction without CRSwNP. The nasal polyps and inferior turbinate mucosa samples applied as negative controls were processed by hematoxylin-eosin (HE) and Gram staining and TNFR-I and TNFR-II–specific immunofluorescent assay. Results: Biofilm was detected in 29 of 36 patients with CRSwNP and in none of the eight negative controls. Staining by HE showed strong correlation with the results of Gram staining protocol. In the biofilm-positive cases, TNFR-I and TNFR-II displayed homogeneous pattern of significantly increased epithelial expression compared to the biofilm-negative nasal polyps. In cases of biofilm absence, the expression pattern of TNF-α receptors was characterized by increased TNFR-II–specific immunoreaction. It was found that biofilm detectability corresponded to the integrity of nasal epithelium and to the dominant inflammatory cell type of the subepithelial layer. Conclusions: Persisting biofilms might increase the epithelial sensitivity against TNF-α that result in epithelium destruction. Coexistence of biofilms and increased TNFR expression might explain the inflammatory mucosal changes, functional disorders, and therapy resistance featuring CRSwNP. Laryngoscope,, 2012

The outer hair cells of organ of Corti are innervated by the efferent neurons of medial olivocochlear neurons (MOC) of the brainstem which modify the cochlear auditory processing and sensitivity. Most of the MOC neurons are excited by a dominant ear and only a small portion of them is excited by both ears resulting in a binaural facilitation. The functional role of the feedback system between the organ of Corti and the cochlear efferent neurons is the protection of the ear from acoustic injury. The rapid impulse propagation in the bilateral olivocochlear system is suggestive of an electrotonic interaction between the bilateral olivocochlear neurons. The morphological background of the MOC pathway is not yet completely characterized. Therefore, we have labeled the bilateral cochlear nerves with different neuronal tracers in guinea pigs. In the anesthetized animals the cochlear nerves were exposed in the basal part of the modiolus and labeled simultaneously with different retrograde fluorescent tracers. By using confocal laser scanning microscope we could detect close appositions between the dendrites of the neurons of bilateral MOC. The distance between the neighboring profiles suggested close membrane appositions without interposing glial elements. These connections might serve as one of the underlying mechanisms of the binaural facilitation mediated by the olivocochlear system.

Several studies have reported a potential genetic association between disease-specific single nucleotide polymorphism (SNPs) of RELN and otosclerosis and confirmed RELN expression in human stapes footplates. These are conflicting results, since RELN expression has been attributed exclusively to neural tissues and to odontoblasts. Otosclerosis is a disease of complex bone remodeling disorder, which is limited to the human otic capsule. Genetic predisposition has long been suspected, however, the pathogenesis remained unclear. Ankylotic stapes footplates (n = 85), cortical bone fragments (n = 4), hearing ossicles (n = 2) and human brain tissue specimens (n = 4) were processed to RELN-specific RT-PCR and reelin-specific immunofluorescent assay (IFA). The first group of ankylotic stapes footplates (n = 22) showed a consistent positive reaction against reelin by IFA; however, RELN-specific mRNA could not be detected in the second, RT-PCR group (n = 63). Brain specimens were characterized by robust expression of reelin (n = 2) and RELN-specific mRNA (n = 2). In case of bone-specific controls (n = 6), reelin/RELN expression was excluded obviously. Concerning current observations, RELN gene does not show active expression in adult stapes footplates. Since, the otic capsule surrounds a special neural structure (membranous labyrinth), reelin might play a coordinative role in the early embryonic stage of development. As being a part of the otic capsule, stapes footplate might be characterized by persisting reelin detectability without mRNA expression. Between these conditions, the etiologic role of RELN is questionable in the pathogenesis of otosclerosis.

Objectives/Hypothesis: Since the concept of tinnitus dopaminergic pathway emerged, studies have been proposed to investigate if dopaminergic agents influence tinnitus. We hypothesized that pramipexole, an agonist on D2/D3 receptors, may antagonize tinnitus in the presbycusis patients (in the frequency range of 250 to 8,000 Hz) in a dose schedule accepted for the treatment of Parkinson's disease in elderly people. Study Design: We designed a randomized, prospective, placebo-controlled and double-blind trial. Methods: Forty presbycusis patients aged 50 years or older with subjective tinnitus were randomized to two groups (20 patients in both). Patients in the drug group took pramipexole over a period of 4 weeks according to a treatment schedule as follows: week 1, 0.088 mg t.i.d.; week 2, 0.18 mg t.i.d.; week 3, 0.7 mg t.i.d.; week 4, 0.18 mg t.i.d. over 3 days and 0.088 mg t.i.d. the rest of the week. Patients in the second group received placebo. Determination of subjective grading of tinnitus perception, the tinnitus handicap inventory (THI) questionnaire and electrocochleography (ECOG) examinations served as the end points. Subjective audiometry was used to produce secondary data. A significant improvement in tinnitus annoyance is found in the group treated with pramipexole versus placebo with respect to inhibition of tinnitus and a decrease of tinnitus loudness greater than 30 dB. However, neither ECOG nor subjective pure-tone threshold audiometry revealed any change in hearing threshold in response to either pramipexole or placebo. Conclusions: Pramipexole is an effective agent against subjective tinnitus associated with presbycusis at a dose schedule used for the treatment of Parkinson's disease. The drug did not change hearing threshold. Laryngoscope, 2011

There is no significant difference in speech recognition scores obtained with the Vibrant Soundbridge and the open-fit hearing aid. However, the Vibrant Soundbridge may be superior to open-fit hearing aids in improving hearing at high frequencies (4-8 kHz).To assess whether an improvement in speech recognition conferred by Vibrant Soundbridge is more marked than that afforded by open-fit hearing aids in patients with sloping high frequency sensorineural hearing loss (SNHL).This study had a self-control prospective design. Seven patients aged 21-62 years with sloping high frequency SNHL were recruited into the study. Each patient received a Vibrant Soundbridge middle ear implant (Vibrant MED-EL) and wore an open-fit hearing aid (Danavox, DOT 10). Speech recognition tests were performed according to protocols suggested by árpád Götze's speech definition test in Hungarian language. In the first session, conventional hearing thresholds (unaided pure tone thresholds) were measured. In the second session, the aided sound-field threshold, speech understanding score and functional gain obtained using middle ear implants and open-fit hearing aids were determined after programming of the devices.Regarding speech recognition scores, there were no significant differences between data obtained with the middle ear implant and those with the open-fit hearing aid.

OBJECTIVE To characterize the pneumatization of the temporal bone in age-matched healthy children and in children with otitis media with effusion (OME). STUDY DESIGN Prospective case-control study. SETTING Tertiary hospital center. PATIENTS This study included 40 healthy children and 56 children with OME, with age ranging from 2 to 18 years. INTERVENTION Mastoid volume and surface determination by 3-dimensional reconstruction of axial temporal bone computed tomographic images. MAIN OUTCOME MEASURE Mastoid volume and surface area comparison of healthy children and children with OME. RESULTS The mastoid cell system (MCS) grows continuously up to the age of 18 years, with different intensities. The mean ± SD MCS volume and surface of children with OME are significantly lower (2.82 ± 1.51 ml and 40.45 ± 18.14 cm, respectively) than those of healthy children (10.05 ± 5.3 ml and 84.47 ± 37.95 cm, respectively). The mastoid volume and surface area of the left and right ears correlate well in healthy children. In children with bilateral OME, the ipsilateral and contralateral ears can be largely different. The ratio of surface and volume is constant in age groups. CONCLUSION In children with OME, the functional volume of MCS acting as a pressure buffer and the surface area serving for gas exchange are small. In case of OME, 1 ear could be more seriously affected by the disease. Otitis media with effusion presumably has a negative effect on the mastoid pneumatization process. The surface-to-volume ratio is constant through chronological age and is a good indicator of a normal middle ear function.

Objectives To review our current knowledge of the etiopathogenesis of otosclerotic bone remodeling including genetics, viral infection, autoimmunity and inflammation and to discuss disease pathogenesis with relevance for pharmacotherapy. Systematic review methodology Relevant publications on the etiopathogenesis, molecular biology, genetics and histopathology of otosclerosis from 1984 to 2009 were analyzed. Results and conclusions Otosclerosis is a bone remodeling disorder of the human otic capsule, however, the etiopathogenesis remains unclear. Genetic predisposition, disturbed bone metabolism, persistent measles virus infection, autoimmunity, hormonal and environmental factors also may play contributing roles in the pathogenesis of otosclerosis. Since, diagnosis of otosclerosis is still based on histopathological examination of the removed stapes footplate, systemic prospective studies based on comprehensive histopathological and molecular biological analysis are necessary to get further information about the background of disease.

Hereditary hearing loss (HL) is a very heterogeneous trait, with 46 gene identifications for non-syndromic HL. Mutations in GJB2 cause up to half of all cases of severe-to-profound congenital autosomal recessive non-syndromic HL, with 35delG being the most frequent mutation in Caucasians. Although a genotype-phenotype correlation has been established for most GJB2 genotypes, the HL of 35delG homozygous patients is mild to profound. We hypothesise that this phenotypic variability is at least partly caused by the influence of modifier genes. By performing a whole-genome association (WGA) study on 35delG homozygotes, we sought to identify modifier genes. The association study was performed by comparing the genotypes of mild/moderate cases and profound cases. The first analysis included a pooling-based WGA study of a first set of 255 samples by using both the Illumina 550K and Affymetrix 500K chips. This analysis resulted in a ranking of all analysed single-nucleotide polymorphisms (SNPs) according to their P-values. The top 250 most significantly associated SNPs were genotyped individually in the same sample set. All 192 SNPs that still had significant P-values were genotyped in a second independent set of 297 samples for replication. The significant P-values were replicated in nine SNPs, with combined P-values between 3 x 10(-3) and 1 x 10(-4). This study suggests that the phenotypic variability in 35delG homozygous patients cannot be explained by the effect of one major modifier gene. Significantly associated SNPs may reflect a small modifying effect on the phenotype. Increasing the power of the study will be of greatest importance to confirm these results.

To characterize the groups of middle ear effusions (MEE) defined on the basis of the ratio of albumin and immunoglobulin G concentrations (A/G) in the effusion and to identify the correlation between these groups of MEE and the clinical features of otitis media with effusion (OME).A laboratory analysis of 88 samples of MEE and a retrospective analysis of the medical history of all patients was performed.Tertiary referral center.Thirty-three girls and 23 boys with OME were included in the study.The concentrations of albumin, immunoglobulins (IgG, IgA, and IgM), complement factors (C3, C4), and C-reactive protein were determined by means of nephelometry. Enzyme-linked immunosorbent assay was used to measure cytokines interferon-gamma, tumor necrosis factor alpha, interleukin (IL)-4, and IL-10 concentrations. Groups were defined according to A/G ratio in the effusions. Thirty-five children underwent allergy testing.Two groups of MEE could be recognized on the basis of A/G ratio; the ratio was lower than 0.7 in group A and was higher than 0.7 in group B.Increased levels of interferon-gamma and tumor necrosis factor alpha were observed in group A, whereas IL-4 and IL-10 were dominating in group B. No association was found between the MEE groups and the clinical features of the disease or the atopic status of the patient.These results suggest that various groups of OME can be categorized according to the differences in A/G ratio in the effusions. These differences can reflect the variances in the pathomechanism of the development of the effusion, the stage of the disease, or the clinical background of the patients.

A 25-year-old woman who developed transient neurological abnormalities after scuba diving is reported. The subsequent day she experienced transient left-side monocular blindness. Arterial ocular occlusion in apparently healthy young women is unusual, and a search for the cause of this devastating vascular event is mandatory. Occlusion of the left branch retinal artery, total occlusion of the left internal carotid artery, and a petrous apex epidermoid were found, together with a shortened prothrombin time (INR: 0.73), a slightly elevated serum cholesterol level (6.1 mmol/l) and combined thrombophilia (elevated FVIIIC plus type 2 sticky platelet syndrome). This case underlines the complex mechanism of thromboembolic diseases, and the importance of the acquired trigger (in the present case scuba diving) in addition to the long-term anatomical and biochemical risk factors.

Hypothesis: Persistent measles virus infection of the otic capsule is suggested to be an etiologic factor in otosclerosis. Otosclerosis is a disease of complex unknown etiology causing progressive conductive and/or sensorineural hearing loss (HL). Background: Diagnostic methods of otosclerosis are sensitive to ossicular chain fixation with low specificity for otosclerotic stapes ankylosis. Methods: Nucleic acid was extracted from stapes footplates of clinically stapes fixation patients (N = 213). Measles virus nucleoprotein RNA was amplified by reverse-transcriptase polymerase chain reaction. Amplification results were correlated to histologic findings in 49 cases. Antimeasles IgG levels of all clinically stapes fixation as well as control sera specimens were measured by enzyme-linked immunosorbent assay. Results: Among clinically stapes fixation patients, 141 stapes footplates contained measles virus RNA. Among 49 histologic specimens, viral RNA was detectable only in histologically otosclerotic stapes footplates (n = 35). Histology for virus-negative footplates (n = 14) excluded otosclerosis. Antimeasles IgG levels were significantly lower in the sera of patients with virus-positive stapes than in control sera. Conclusions: Combination of decreased antimeasles IgG serum level and conductive HL has a great specificity and sensitivity as a diagnostic method in the preoperative evaluation of ossicular chain fixations otosclerosis. Low antimeasles IgG level indicates otosclerosis, whereas high level suggests nonotosclerotic ossicular chain fixations. Preoperative elucidation of the cause of a conductive HL may suggest optional medical treatment in preference to surgical methods.

The aim of the present work was to study whether neurotoxicity produced by cisplatin modified tissue insulin sensitivity in guinea-pigs. One week after selective sensory denervation of the anterior hepatic plexus by means of perineurial 2% capsaicin treatment, hyperinsulinaemic euglycaemic glucose clamp were performed to estimate insulin sensitivity in male guinea-pigs. The guinea-pigs underwent regional sensory denervation of the anterior hepatic plexus exhibited insulin resistance, whereas systemic capsaicin desensitization increased insulin sensitivity. Intraportal administration of l -nitro-arginine methyl esther (L-NAME decreased, whereas capsaicin increased insulin sensitivity. Neither atropine nor acetylcholine produced any significant effect. In animals with preceding regional capsaicin desensitization, none of the pharmacological maneuvers modified the resulting insulin resistant state. Cisplatin pretreatment induced sensory neuropathy and decreased insulin sensitivity. Insulin sensitivity did not change after either regional or systemic capsaicin desensitization in the cisplatin-treated animals. CGRP8–37, a nonselective calcitonin gene-related peptide (CGRP) antagonist (50 μg/kg i.v.), significantly increased insulin sensitivity in normal animals but only a tendency to insulin sensitization was seen after cisplatin treatment. Cisplatin treatment, similar to regional capsaicin desensitization of the anterior hepatic plexus, produced a significant decrease in insulin-stimulated uptake of 2-deoxy- d [ l- 14C] glucose in cardiac and gastrocnemius muscle with no effect on percentage suppression of endogenous glucose production by hyperinsulinaemia. We conclude that the majority of cisplatin-induced insulin resistance is related to functional deterioration of the hepatic insulin sensitizing substance (HISS) mechanism.

Hypothesis Persistent measles virus infection of the otic capsule is presumed to be one of the etiologic factors in otosclerosis. The viral pathogenesis of otosclerosis could be established only by correlative analysis: histologic examination of the stapes footplates and reverse-transcriptase polymerase chain reaction amplification of the viral RNA. At present, histologic analysis of the removed stapes footplates is the only appropriate method of distinguishing otosclerotic and nonotosclerotic stapes fixations. Background The presence of measles virus was shown in otosclerotic patients by reverse-transcriptase polymerase chain reaction amplification of the viral RNA and detecting the viral proteins by immunohistochemistry. Methods Nucleic acids (mRNA, vRNA, and DNA) were extracted from ankylotic stapes footplates of stapes fixation patients (n = 44). Measles virus genomic nucleoprotein RNA was amplified by seminested reverse-transcriptase polymerase chain reaction. Amplification results were correlated to postoperative histologic findings. Results Measles virus RNA was detectable only in histologically otosclerotic stapes footplates (n = 32). Histology for virus-negative footplates (n = 12) excluded otosclerosis. Virus-negative stapes footplates showed annular calcification (n = 8), bone resorption with increased numbers of hemosiderophages (n = 2), and mononuclear cell infiltration with osteolysis (n = 2). Conclusion Stapes ankylosis is a heterogenous disease causing conductive hearing loss with different causes. Nonotosclerotic stapes fixations may belong to degenerative disorders with variable histopathology. Otosclerosis is an inflammatory disease resulting from persisting measles virus infection of the otic capsule.

Slow motile length changes of isolated, apical turn outer hair cells (OHCs) (n=36) were induced by perfusion of saline (flow rate: 0.6 microl/min) as a mechanical challenge or by perfusion of 12.5 mM KCl solution for 90 s as a chemical and mechanical challenge with and without ocadaic acid (OA), a serine/threonine protein phosphatase inhibitor. Electromotility was evoked by square pulses from +/-35 mV to +/-240 mV during the slow shortening and recovery period (n=36). Stiffness of the lateral wall was measured by the micropipette aspiration technique (n=20). Saline perfusion caused a reversible shortening of 774+/-87 nm (n=9) as well as K+ of 1465+/-159 nm (n=9). Slow shortening increased lateral wall stiffness (1.25+/-0.02 to 1.52+/-0.03 nN/microm) (n=5-5). Simultaneously, electromotility magnitude decreased (n=9). Ocadaic acid blocked slow shortening, increased lateral wall stiffness, and decreased the magnitude of electromotility. Mechanical or mechanical+chemical stimulation of ocadaic acid treated OHCs do not further change stiffness or electromotility. Isolated OHCs respond with slow shortening and consutive cell stiffness increase to mechanical insult. This phenomenon seems operating with calcium-, and phosphorylation-dependent modifications of the cytoskeletal proteins. The subsequent electromotility gain decrease suggests a slow OHC shortening driven regulation of the cochlear amplifier with simultaneous safety control of the auditory periphery against overstimulation.

Hypothesis: Otosclerosis is a disease of unknown etiology causing conductive or sensorineural hearing loss. Persistent measles virus infection of the otic capsule is considered to be one of the etiologic factors in otosclerosis. Background: Determinants of measles virus infection and reactive inflammation were studied in otosclerosis. The presence of measles virus was shown in otosclerotic patients by reverse-transcription polymerase chain reaction (RT-PCR) amplification of the viral RNA. No report is available, however, on the types and features of paracrine cytokines in otosclerosis. Methods: Nucleic acid was extracted from stapes footplate samples of clinically otosclerotic patients. Measles virus nucleoprotein RNA was amplified by seminested RT-PCR. Tumor necrosis factor (TNF)-alpha mRNA expression was detected by RT-PCR in otosclerotic bone and was correlated with preoperative audiologic findings and measles virus positivity. Results: Among 154 clinically otosclerotic patients, 99 stapes footplate specimens contained measles virus RNA. TNF-alpha mRNA was detectable in 88 virus-positive and in 6 virus-negative stapes footplates. There was no detectable TNF-alpha mRNA expression in virus negative cases. Conclusion: The etiologic role of measles virus in the pathogenesis of otosclerosis should be considered. Detection of TNF-alpha mRNA demonstrates activated osteoclast functions and inflammatory pathways in otosclerotic stapes footplates associated with measles virus presence. Virus-associated and virus-negative pathomechanisms of otosclerosis should be distinguished.

Objective To test the application of the nerve-muscle pedicle (NMP) technique for selective reinnervation of previously denervated posterior cricoarytenoid (PCA) muscle. Methods The left recurrent laryngeal nerve (RLN) was severed in 5 mongrel dogs, and an ansa cervicalis-sternohyoid muscle pedicle was sutured to the left PCA muscle. Three dogs underwent a sham operation. Videolaryngoscopy was performed, and electromyographic data were collected after 1 year on average. Finally, histologic analysis of the NMP was performed. Results The video records showed the return of mobility of the PCA muscle reinnervated by the NMP. EMG data as to show evoked polyphasic potentials showed also evidence of reinnervation of the PCA muscle. With immunohistochemical reaction (antineurofilament antibody+biotin) we could show neurofilaments and motor endplates in both sides in all 5 animals. Conclusions The NMP technique could eliminate the need for arytenoidectomy and laterofixation in patients with unilateral or bilateral vocal fold paralysis. The quality of life and voice may be improved.

The electromotile performance of isolated OHCs does not seem to be dependent on slow motile shortening alone; other mechanisms, such as phosphorylation, are also involved.To elucidate the relationship between the magnitude of electromotile displacements and magnitude of slow motile shortening of outer hair cells (OHCs) induced by mechanical or chemical stimulation over a reversible range.Isolated guinea pig OHCs were mechanically (0.6 microl/min perfusion of saline; n =4) or chemically and mechanically (0.6 microl/min perfusion of 12.5 mM KCl; n =4) stimulated in a glass microchamber to evoke slow motile shortening.Combined mechanical and chemical stimulation evoked greater OHC shortening than mechanical stimulation alone. Both forms of stimulation resulted in reversible shortening. Electromotility was measured using low voltage (+/- 35 mV) and higher voltage (up to +/- 240 mV) electrical pulses mimicking the receptor potential at different stages of cell shortening. The magnitude of electromotility decreased simultaneously with slow motile shortenings of OHCs. Irrespective of the character of the stimulus (mechanical or mechanical + chemical), the decrease in the magnitude of electromotility was dependent on the degree of cell shortening. Ocadaic acid, a protein phosphatase inhibitor, blocked slow motility and decreased the magnitude of electromotility.

ATP acts as a neuro-modulator through purinoceptors in many different tissues. Many subtypes of these receptors have been identified in the inner ear, but so far only two types have been shown to be present in the membrane of the isolated outer hair cells (OHCs). The aim of this study was to detect and visualize the existence and distribution of purinoceptor subtypes as well as to study the [Ca(2+)](i) response of these cells in response to stimulation with ATP. Four P2X and three P2Y receptor subtypes were identified with different expression pattern in the membrane of guinea pig outer hair cells. Whereas intense labeling was observed for P2X1, P2X2, P2X4, P2Y1, P2Y2, and P2Y4, the labeling for the subtype P2X7 was weak. There was a marked difference in the distribution of the receptors along the surface of the cells with a homogenous distribution in cases of P2X1, P2X4, and P2Y1. In contrast, P2X2 and P2Y2 receptor density was high mainly at the apical, while P2X7 and P2Y4 at the basal pole of the cells. Similarly a heterogeneity was observed in the ATP-induced transient elevation in [Ca(2+)](i), which had either fast kinetics without desensitization or slow rise with desensitization.

Hereditare Schwerhorigkeit ist eine extrem heterogene sensorische Erkrankung, wobei die nichtsyndromalen Formen einen Anteil von ungefahr 70% einnehmen. Bisher konnten lediglich 2 Loci (DFNA1, DFNA6/14/38) identifiziert werden, die mit einer sensorineuralen Tieftonschwerhorigkeit assoziiert sind. Der Lokus fur DFNA6 konnte auf Chromosom 4p16 kartiert werden. Das hier lokalisierte Gen, WFS1 (Wolframin), wurde bereits mit dem rezessiv vererbten Wolfram-Syndrom in Verbindung gebracht. Des Weiteren konnen Mutationen in diesem Gen eine autosomal-dominante sensorineurale Tieftonschwerhorigkeit verursachen. In unserer Studie analysierten wir den Phanotyp einer grosen ungarischen Familie mit Tieftonschwerhorigkeit, bei der wir in vorangegangenen Analysen eine Kosegregation zu der DFNA6-Region nachweisen konnten. 14 Mitglieder dieser Familie zeigen einen postlingualen, sensorineuralen, bilateralen, symmetrischen, nichtsyndromalen Horverlust im Tieftonbereich mit langsamer Progression. Keiner der Probanden zeigte Gleichgewichtsstorungen oder Sehstorungen.

The stiffness of the outer hair cell (OHC) lateral wall, measured by the micropipette aspiration technique, is non-linear, decreasing from the ciliary pole (stiffness parameter S p 1.83±0.13 nN/µm n=10) towards the cell base (S p 1.14±0.16 nN/µm, n=10) irrespective of the cochleoapical or cochleobasal origin of the cells. The length of the aspirated lateral wall segment was related exponentially to the duration of the applied negative pressure (6 cm H2O) in the synaptic region of the OHCs whereas an active, sigmoid component was observed between 30 and 60 s in the supranuclear regions. A significant increase of the midlateral wall stiffness (to 1.91±0.23 nN/µm; n=10) was observed in calcium-free medium and the sigmoid component of the response of the lateral wall was abolished. Salicylate (5 mM) had no significant effect on the active sigmoid behaviour of the lateral wall (n=10). Gadolinium (5 mM), a non-specific cation channel blocker, increased the stiffness of the lateral wall and attenuated the active component (n=10). The motor protein prestin thus does not seem to be involved in the active stiffness regulation seen in this study. A role for the cortical cytoskeleton in the regulation of stiffness seems reasonable according to our model. The mechanism may involve calcium-dependent metabolic modification of cytoskeletal or membrane proteins.

To determine whether chronic suppurative otitis media may cause sensorineural hearing loss.The files of 121 patients with unilateral chronic suppurative otitis media were reviewed in a retrospective study. Air conduction and bone conduction threshold averages were calculated over the speech frequencies (500 Hz, 1,000 Hz, and 2,000 Hz). Thresholds at 4 kHz were examined separately but in a similar way. Multiple linear regression models were used to clarify the relationships between sensorineural hearing loss and chronic otitis media.Chronic suppurative otitis media was seen to be associated with sensorineural hearing loss. When age and normal side were corrected for, pure-tone threshold and bone conduction threshold at either the speech frequencies or at 4 kHz increased gradually according to the duration of the chronic suppurative otitis media. The threshold shift was more accentuated as age increased. The sensorineural hearing loss at 4 kHz seemed to be higher than that at the speech frequencies.The inner ear is vulnerable against chronic suppurative otitis media. Older age increases this vulnerability. The proximity of the sensory cells to the potential source of harm (inflamed middle ear) may mean higher exposure, as reflected by the fact that sensory cells processing higher frequencies are more seriously damaged.

Enzymatically isolated type I spiral ganglion neurons of the guinea pig have been investigated in the present study. The identity of the cells was confirmed by using anti-neuron-specific enolase immunostaining. The presence and shredding of the myelin sheath was also documented by employing anti-S100 immunoreaction. The membrane characteristics of the cells were studied by using the whole-cell patch-clamp technique. The whole-cell capacitance of the cells was 9 +/- 2 pF (n = 51), while the resting membrane potential of the cells was -62 +/- 9 mV (n = 19). When suprathreshold depolarizing stimuli were applied, the neurons fired a single action potential at the beginning of the stimulation. It was confirmed in this study that type I spiral ganglion cells possess a hyperpolarization-activated nonspecific cationic current (Ih). The major characteristics of this current component were unaffected by the enzyme treatment. Type I spiral ganglion cells also expressed various depolarization-activated K+ current components. A high-threshold outward current was sensitive to 1-10 mm TEA+ application. The ganglion cells also expressed a relatively small, but nevertheless present, transient outward current component which was less sensitive to TEA+ but could be inhibited by 100 micro m 4-aminopyridine. A DTX-I-sensitive current was responsible for some 30% of the total outward current (at 0 mV), showed rapid activation at membrane potentials positive to -50 mV and demonstrated very little inactivation. However, inhibition of the highly 4-AP- or DTX-I-sensitive component did not alter the rapidly inactivating nature of the firing pattern of the cells.

Hereditary hearing impairment (HHI) is a heterogeneous class of disorders that shows various patterns of inheritance and involves a multitude of different genes. Mutations in the EYA4 gene are responsible for postlingual, progressive, autosomal dominant hearing loss at the DFNA10 locus. EYA4 is orthologous to the Drosophila gene eya (“eyes absent”), a key regulator of eye formation. EYA4 plays an important role in several developmental processes. Here we report a Hungarian family displaying sensorineural, progressive hearing impairment. The family comprising four generations with 11 affected and 8 unaffected members was subjected to genome-wide linkage analysis and candidate gene sequencing. By linkage analysis, the chromosomal region 6q22.3 was shown to segregate with the disease. Mutation analysis of the EYA4 gene, which maps to 6q22.3, revealed an insertion of 4 bp (1558insTTTG) in all affected family members. This insertion creates a frameshift and results in a stop codon at position 379. Hence, nearly the complete “eya homologous region” (eyaHR), which is essential for the protein function, would be deleted in the mutant EYA4 protein if the transcription were found to be stable. This family is the third one linked to DFNA10 and revealing a mutation in the EYA4 gene. In all three families, the mutations are localized in different regions of the eyaHR, suggesting that this protein contains several functional subregions with different tissue-specific importance.

There are a number of well-known stimulation methods for the investigation of the central projection of the vestibular system. In addition to optokinetic, galvanic and neck vibration tests, the most widespread method is caloric stimulation. These listed methods cause not only vestibular, but also other effects on the central nervous system (CNS) (acoustic, tactile and nociceptive). In this paper, positron emission tomography (PET) was used to investigate whether caloric stimulation contains a non-vestibular (extravestibular) component, which would cause a distortion in the cortical activity and therefore in the vestibular effect on the CNS. Caloric stimulation was carried out in six patients who had been operated on due to cerebello-pontine angle tumour. These patients suffered post-operatively from a complete lesion of the vestibular system and anacusis on the operated side. Ipsilaterally activated areas were the inferior pole of the post-central gyrus and temporoparietal junction, caudal part of the post-central gyrus (SI, SII), inferior parietal lobule and medial frontal gyrus. Contralaterally activated areas were the anterior cingulate gyrus, medial frontal gyrus, posterior part of the insula, post-central gyrus and temporoparietal junction (SII). Ipsilaterally deactivated areas were the caudal and cranial part of the medial occipital gyrus (V2, V3, V4, V5). Contralaterally deactivated areas were the lingual gyrus, inferior occipital gyrus (V2, V3) and fusiform gyrus. On the basis of these data, it was postulated that, during caloric stimulation, extravestibular reaction also occurs, which corresponds to the subjective feeling of heat and pain. The deactivation of the occipital cortex due to an extravestibular effect was demonstrated. This is the first observation to suggest the possibility of nociceptivevisual interaction.

Evaluation of voice quality parameters of esophageal speech in different neoglottis forms after total laryngectomy.Presentation of voice analysis of 20 patients, who underwent total laryngectomy. The success of acquiring this technique was estimated by means of a voice analyzing program (pitch, sound-holding, loudness, spectrogram),and by the intelligibility via the telephone. Shape of the different types of neoglottis that developed and its functioning during vocalization and continuous speech were observed by nasal endoscopy. Data obtained from the voice analysis were compared among the observed three different neoglottis forms.The average dysphonia index of the 20 patients was 1.67 ± 0.38 (mean ± SD). Nasal fiberoscopic examination revealed three different types of neoglottis forms – a small mucosal button, two mucosal battens, and a mucosal lip. Voice quality of the esophageal speech of the patients with the mucosal button was found to be the closest to normal by subjective and objective acoustical evaluation.These findings emphasize the importance of the proper wound closure technique which can facilitate the development of a special button shape neoglottis form and help to acquire esophageal speech with the best quality parameters shortly after total laryngectomy.

Twenty temporal bones (TBs) were removed from autopsy cases and prepared for immunohistochemical examination. Ten TBs were free of ear disease whereas the other ten TBs showed the signs of chronic otitis media. Expression of markers for monocyte-macrophages (25F9, 27E10) and natural killer cells (anti-Leu-11) was examined immunohistochemically. There were no specific positive stainings with 25F9 or anti-Leu-11 antibodies in any of the specimens. Staining for 27E10 was found to be negative in each section obtained from normal cochlea. However, 27E10 positivity was detected in three of ten TBs with signs of chronic ear inflammation. This positivity can be explained by two theories: (1) activated monocytes can enter the inner ear from the systemic circulation as a consequence of chronic antigen challenge; (2) mesothelial cells could become activated as a result of a cross-reaction, with resultant positivity. Development of sensorineural hearing loss in some cases of chronic otitis media may be due to these immunological reactions.

Hintergrund und Fragestellung. Die Verbreitung der funktionellen bildgebenden Verfahren eroffnete neue Moglichkeiten bei den vestibularen Forschungen. Obwohl die zerebrale Projektion des Systems von mehreren Verfassern untersucht wurde, werfen die aus den Beschreibungen sich ergebenden Unterschiede weitere Fragen auf. In unserer Publikation stellen wir unsere mittels Positronen-Emissions-Tomographie (PET) erhaltenen Ergebnisse bei gesunden, rechtshandigen Personen dar. Patienten und Methodik. Bei allen Personen wurden rechts- und linksseitige kalorische Prufungen durchgefuhrt (n=6). Die ausgearbeitete Methode kann als eine Standardmethodik angesehen werden, die eine Moglichkeit schafft, aus verschiedenen Forschungsinstituten stammende Untersuchungsergebnisse zu vergleichen. Wir publizieren detaillierte Karten uber die infolge der angewendeten vestibularen Stimulation auftretenden Veranderungen (Gehirnaktivierung: Zunahme der regionalen Blutdurchstromung, bzw. Gehirndeaktivierung: Abnahme der regionalen Blutdurchstromung). Ergebnisse. Die aktivierten Hirnareale stimmen z. T. mit Daten von anderen Forschern uberein. Wir heben aber die Aktivitatszunahme in der Region Brodmann 6 hervor, als eine kortikale Offenbarung der unwillkurlichen isometrischen Skelettmuskulaturspannung. Hinsichtlich der Abnahme der Blutdurchstromung haben wir zahlreiche, bisher nicht beschriebene Regionen gefunden. Schlussfolgerungen. Unter den beschriebenen Regionen mit verminderter Durchblutung mochten wir auf die funktionelle Beziehung von Hippocampus und vestibularem System aufmerksam machen, indem wir als erste eine Deaktivierung ausgewiesen haben.

Isolated guinea-pig outer hair cells (OHCs) (n = 52) were inserted into a partitioning microchamber and electromotility was measured by a calibrated optoelectronic apparatus. Acetylcholine (ACh), and ACh together with different protein kinase inhibitors, were applied to OHCs through a puffer pipette. ACh produced a magnitude increase of electromotility. This magnitude increase was inhibited by co-application of KN-62, a calcium/calmodulin-dependent protein kinase II (CAMKII) inhibitor. Simultaneous application of ACh and H-89, a selective protein kinase A (PKA) inhibitor, did not antagonize the ACh response. Further support for the CAMKII-mediated ACh influence on electromotility is that the magnitude increase is also inhibited by the calmodulin antagonist trifluoperazine (TFP) and by the sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) inhibitor thapsigargin. The results suggest an essential role of calcium in the ACh-mediated increase of the magnitude of electromotility. Elevation of the intracellular calcium concentration apparently activates CAMKII which, in turn, phosphorylates membrane or cytoskeletal substrate(s). This molecular modification probably leads to reduced axial cell stiffness and subsequent increase of the electromotile response.

Tuberculosis remains one of the most challenging infectious diseases, which rarely manifests in the middle ear cleft exclusively. Typical symptoms of tuberculosis have become more and more confusing due to the genetic evolution of different Mycobacterium species. In the diagnosis of tuberculous otitis media (TOM), clinical suspicion plays a fundamental role, when topical and/or systemic antibiotic treatment cannot lead to improvement in ear discharge and inflammation. If there is no other reason of persisting otorrhea, microbiological sampling and culturing are the subsequent steps of diagnosis. These investigations, however, have low sensitivity; therefore a canal wall-up mastoidectomy is recommended, which includes the removal of necrotic bone and multiple histological sampling from various locations. Currently, histopathological analysis is the most robust and reliable method in the diagnosis of TOM. Tuberculin skin test, Mycobacterium-specific PCR and interferon-gamma release assay cannot distinguish between active, inactive or post-infective conditions. According to these considerations, these methods may serve as supplementary assays for the final diagnosis. Having the appropriate diagnosis after surgical intervention and laboratory analysis, medical management should be continued by anti-tuberculosis chemotherapy. Hereby, we demonstrate two cases with primary TOM and provide an overview of the literature in the light of diagnostic and therapeutic guidelines in the management of TOM.

Two groups of isolated, surviving outer hair cells (OHCs) of guinea pig cochleas (n = 20, for each group) were treated with 10 microM acetylcholine or acetylcholine plus strichnine (an alpha9 nAChR antagonist), respectively, under short-term tissue culture conditions. The protein content of the cell homogenates was separated by SDS-polyacrylamide gel electrophoresis, Western blotted and labelled with an antibody against phosphoserine residues. Signals were detected using the ECL system. Acetylcholine challenge of the OHCs resulted in a difference in the pattern of phosphorylated proteins from those of strichnine pretreated cells. A 220 kDa and a 120 kDa protein expressed a more intense phosphorylated state in the ACh group compared with the ACh plus strichnine group. The 220 kDa phosphoprotein is in the range of the cytoskeletal protein beta-fodrin, whereas the 120 kDa fraction is similar to alpha-fodrin or an ankyrin isoform. Phosphorylation of proteins due to activation of the AChR by agonist can play a role in the signalling mechanism between receptor activation and increase in the electromotile capability of isolated OHCs.

The dominant efferent innervation of the cochlea terminates on outer hair cells (OHCs), with acetylcholine (ACh) being its principal neurotransmitter. OHCs respond with a somatic shape change to alterations in their membrane potential, and this electromotile response is believed to provide mechanical feedback to the basilar membrane. We examine the effects of ACh on electromotile responses in isolated OHCs and attempt to deduce the mechanism of ACh action. Axial electromotile amplitude and cell compliance increase in the presence of the ligand. This response occurs with a significantly greater latency than membrane current and potential changes attributable to ACh and is contemporaneous with Ca2+release from intracellular stores. It is likely that increased axial compliance largely accounts for the increase in motility. The mechanical responses are probably related to a recently demonstrated slow efferent effect. The implications of the present findings related to commonly assumed efferent behaviorin vivoare considered.

OHCs were inserted into a partitioning microchamber. Reversible swelling was induced by hyposmotic incubation medium (270 mosm.kg H2O-1). The transfer curve of electromotility was measured by stimulating the OHCs with a series of brief (2.5 ms) square-pulses with both polarities and graded magnitudes. Response magnitude and gain of electromotility were increased in swollen OHCs. On the basis of their electromotile performance-characteristics, swelling appeared to depolarize the OHCs. Transition from contraction dominated asymmetry of motility was observed towards a symmetric response. Depolarization, by itself, cannot explain the gain and magnitude increase. Acetylcholine (ACh) responsiveness of swollen OHCs preserves the pre-challenged pattern: ACh further increases gain and magnitude.

Previous experiments suggested the possibility of a short-term sound stimulus-evoked and transient increase in DPOAE amplitudes. This phenomenon is possibly due to the complexity of the outer hair cells and their efferent control system and the different time scales of regulatory processes. A total of 100 healthy subjects ranging from 18 to 40 years of age with normal hearing and normal DPOAE values in the range of 781–4000 Hz were recruited in the study. Diagnostic DPOAE measurements were performed after short-term sound exposure. We proposed a 10 sec, 50 dB sound impulse as the most effective stimulus for clinical practice between 40 and 60 sec poststimulus time to detect the aforementioned transient DPOAE increase. We developed a procedure for detection of this transient increase in DPOAE by the application of a short-term sound exposure. The phenomenon was consistent and well detectable. Based on our findings, a new aspect of cochlear adaptation can be established that might be introduced as a routine clinical diagnostic tool. A mathematical model was provided that summarizes various factors that determine electromotility of OHCs and serves as a possible clinical application using this phenomenon for the prediction of individual noise susceptibility.

This retrospective case review was performed with the aim to asses the value of cone-beam computed tomography (CBCT) in the preoperative diagnosis of otosclerosis. A total of 32 patients with histologically confirmed stapedial otosclerosis, who underwent unilateral stapedectomies were analyzed. Preoperative temporal bone CBCT scans were performed in all cases. CBCT imaging was characterized by a slice thickness of 0.3 mm and multiplanar image reconstruction. Histopathologic examination of the removed stapes footplates was performed in all cases. Findings of CBCT were categorized according to Marshall's grading system (from grade 0 to grade 3). Histopathologic results were correlated to multiplanar reconstructed CBCT scans, respectively. Histologically active foci of otosclerosis (n = 21) were identified by CBCT in all cases with a sensitivity of 100 %. However, CBCT was unable to detect histologically inactive otosclerosis (n = 11, sensitivity = 0 %). According to CBCT scans, no retrofenestral lesions were found and all positive cases were recruited into the grade 1 group indicating solely fenestral lesions at the anterior pole of stapes footplates. In conclusion, CBCT is a reliable imaging method with considerably lower radiation dose than high-resolution CT (HRCT) in the preoperative diagnosis of otosclerosis. These results indicate that CBCT has high sensitivity and specificity in the detection of hypodense lesions due to histologically active otosclerosis.

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is a multifactorial disease that seems to be associated with the presence of microbial biofilms and corresponding subepithelial inflammatory reactions. Optical coherence tomography (OCT) might be applied to detect bacterial and fungal biofilms in patients with CRSwNP. A total of 27 patients with CRSwNP undergoing endoscopic sinus surgery (ESS) were analyzed. The negative control group consisted of six patients undergoing septoplasty for nasal obstruction without CRSwNP. The nasal polyps and inferior turbinate mucosa specimens applied as negative controls were processed to OCT analysis and H.E. and Gram staining. Biofilm was detected in 22 of 27 patients (81.5 %) with CRSwNP and in none of six negative controls. In our series, OCT scan showed an obvious association with the findings of H.E. and Gram staining and was allocated to be a good predictor of biofilm existence. On OCT images, biofilms were displayed as distinct superficial layers with high optical density. It was found that microscopic architecture of biofilms was strongly associated with the integrity of nasal mucosa and to the cellular pattern of subepithelial inflammatory reaction. This study confirmed the presence of microbial biofilms in patients with CRSwNP according to OCT scans and histological analysis. Since biofilms may affect the severity and recurrence rate of CRS treated by ESS they should be detected preoperatively. In conclusion, single application of OCT analysis or combination with conventional histological protocols provides a robust and reliable method for the detection of bacterial and fungal biofilms in CRSwNP. Level of evidence 3b, individual case–control study.