Hyaluronic acid concentration in the middle ear fluid as an indicator of severity of the secretory otitis in newborns with cleft palate.

The aim of the study was to investigate the hyaluronic acid concentration in middle ear fluid of patients with cleft palate as an indicator of the severity of the disease. Hyaluronic acid was examined in the middle ear fluid of 65 children (48 boys and 17 girls) subjected to cleft lip surgery in neonatal period up to 10 days of age. Patients were divided into 3 groups according to the course of the disease. First group consists of 15 patients with favorable course, second group consist of 25 patients with moderate course, third group included 25 patients with an adverse course. Hyaluronic acid levels were determined by commercially available immunoassay. The concentrations of hyaluronic acid in the middle ear fluid were as follows (mean+SEM): favorable course: 14253+2393 µg/l, moderate course: 7503+1345 µg/l, adverse course: 5905+2393 µg/l. Patients with adverse course and moderate course had significantly decreased hyaluronic acid levels in middle ear fluid compared to the patients with favorable course (P=0.02 and P=0.0018). Hyaluronic acid concentration is related to the course of the disease and the lowest values are most frequent in patients with an adverse course.

Effects of reactive oxygen species generation induced by Wonju City particulate matter on mitochondrial dysfunction in human middle ear cell.

Atmospheric particulate matter (PM) contains different components that can elicit varying adverse health effects in humans and animals. Studies on PM toxicity and its underlying mechanisms in the middle ear are limited, and they generally use a PM standard. However, as PM composition varies temporally and geographically, it is crucial to identify the toxic PM constituents according to season and region and investigate their associated health effects. Thus, we sought to determine whether PM induces cytotoxicity and inflammatory factor and reactive oxygen species (ROS) generation in human middle ear epithelial cells obtained from patients with otitis media. The cells were treated with both standard urban PM and PM directly captured from the atmosphere in Wonju City. The association between mitochondrial dysfunction and PM was investigated. PM exposure significantly increased COX-2 and TNF-α mRNA expression, increased ROS generation, induced inflammatory responses, and caused abnormalities in mitochondrial motility and function. Furthermore, PM induced cell apoptosis, which consequently reduced cell survival, particularly at the concentration of 100 µg/mL. Overall, our study provides new insights into the toxic effects of standard and atmospheric PM on middle ear cell line.

Correlation of pathogenic effects of laryngopharyngeal reflux and bacterial infection in COME of children.

BACKGROUND: Bacteria infection and laryngopharyngeal reflux (LPR) were believed the important pathogenesis of chronic otitis media with effusion (COME). But no study researched the relationship between them on COME. AIMS: To confirm bacterial could arrive middle ear through LPR and produced acid metabolites to activate the pepsinogen of LPR causing COME. MATERIAL AND METHODS: Children (65) diagnosed COME with 122 middle ear effusions were included in COME group. Children (22) with congenital/acquired profound deafness with 22 middle ear lavage were included in CI group. Pepsin A concentration in the effusion and lavage fluid were measured. The DNA of the bacteria, IL-8 and TNF-α in the effusion were detected. RESULTS: The average concentration of pepsin A in the effusions and lavage were 176.65 ± 242.09 and 19 ng/ml. Bacterial infection rates were 75.76% and 24.24% in the pepsin A(+) and pepsin A(-) patients. In the bacterial (+), the patients of pepsin A(+) was 4.33 times higher than those of pepsin A(-). TNF-α in pepsin A(+) was higher than that in pepsin A(-). TNF-α and IL-8 were higher in bacteria(+) than those of bacteria(-). CONCLUSIONS: Bacterial infection and LPR might act in synergy in the pathogenesis of COME. SIGNIFICANCE: First time to propose LPR and bacterial infection might work synergistically to cause COME.

Correlation Between Adenoid Hypertrophy, Tympanometry Findings, and Viscosity of Middle Ear Fluid in Chronic Otitis Media With Effusion, Southern Oman.

Otitis media with effusion is a common cause of diminished hearing in children younger than 12 years. Hypertrophy of adenoids is one of the commonest etiologies of this condition. It has been mentioned that with increased size of the adenoid tissue, the more likely the incidence of fluid in the middle ear. The aim of this study was to find whether there is a correlation between adenoid size, tympanometric findings, and type of fluid in the middle ear irrespective of disease duration. This is a prospective study done on 100 pediatric patients (12 years and less) presented with chronic otitis media with effusion (COME) and adenoid hypertrophy from July 2015 till July 2017. Cases with tympanometry evidence of COME (B, Cs) and adenoid hypertrophy seen by nasal endoscopy were included. Adenoid size was graded and correlated with the type of tympanometry and type of fluid in the middle ear. Sixty male children and 40 female children were involved. Age ranged from 3 to 12 years with a mean of 7.19 ± 2.489 years. Highly significant relation existed between grade 4 adenoid hypertrophy and mucoid nature of middle ear fluid (P value = .000). There is a highly significant relation between adenoid hypertrophy grade Ⅳ and type B tympanometry. There is a highly significant relation between adenoid size and nature of middle ear fluid irrespective of the duration of complaints, where grade Ⅳ adenoid hypertrophy showed more increase in middle ear effusion viscosity making adenoid size a very important predictor for the tympanometry type and the nature of the fluid in the middle ear.

Mixed epithelial and stromal tumor of the middle ear: The first case report.

We report a tumor arising in the middle ear of a 65-year-old female patient that was composed of an ovarian-type stroma (OS) and an epithelial component. The tumor consisted of irregular, polypoid masses containing multiple variably sized cystic spaces, which were invariably surrounded by the OS. The cystic spaces were lined by flat, cuboidal, or columnar epithelial cells, in most parts showing mucinous differentiation. The epithelial lining of the cysts strongly expressed cytokeratins AE1-3, CK7, CK8, CK18, CK19, EMA, and S100 protein. The stroma expressed CD34 and smooth muscle actin. No cytological atypia or mitoses were present, and the proliferative activity was less than 1% in both components. The clonality analysis proved the clonal nature of the neoplasm. We believe that this tumor is a new member in the family of neoplasms containing the OS, and therefore we propose the term mixed epithelial and stromal tumor of the middle ear.

Optical detection of middle ear infection using spectroscopic techniques: phantom experiments.

A noninvasive optical technique, which is based on a combination of reflectance spectroscopy and gas in scattering media absorption spectroscopy, is demonstrated. It has the potential to improve diagnostics of middle ear infections. An ear phantom prepared with a tissue cavity, which was covered with scattering material, was used for spectroscopic measurements. Diffuse reflectance spectra of the phantom eardrum were measured with a reflectance probe. The presence of oxygen and water vapor as well as gas exchange in the phantom cavity were studied with a specially designed fiber-optic probe for backscattering detection geometry. The results suggest that this method can be developed for improved clinical detection of middle ear infection.

Restoring susceptibility induced MRI signal loss in rat brain at 9.4 T: A step towards whole brain functional connectivity imaging.

The aural cavity magnetic susceptibility artifact leads to significant echo planar imaging (EPI) signal dropout in rat deep brain that limits acquisition of functional connectivity fcMRI data. In this study, we provide a method that recovers much of the EPI signal in deep brain. Needle puncture introduction of a liquid-phase fluorocarbon into the middle ear allows acquisition of rat fcMRI data without signal dropout. We demonstrate that with seeds chosen from previously unavailable areas, including the amygdala and the insular cortex, we are able to acquire large scale networks, including the limbic system. This tool allows EPI-based neuroscience and pharmaceutical research in rat brain using fcMRI that was previously not feasible.

Carcinoid tumor of the middle ear: a case report and review of literature.

Carcinoid tumors of the middle ear are very rare. Here we describe a 37-year-old man with multiple recurrent carcinoid tumor of the right middle ear. The CT demonstrated the recurrent mass that filled the tympanum and mastoid with osteolytic invasion, and the tumor was removed by surgery. The pathological findings showed the tumor cells, without necrosis and mitotic activity, had round, oval, or slightly irregular nuclei and finely-dispersed chromatin, arranged in cords, nests, and glandular structures. They were strongly positive for synaptophysin and CD56, but were negative for S-100 and chromogranin A. Ki-67 proliferation activity was low (<2%). With a review of the literature, the clinical, pathological characteristics and treatment modalities of this rare tumor are discussed.

Extratympanic observation of middle ear structure using a refractive index matching material (glycerol) and an infrared camera.

High-resolution computed tomography has been used mainly in the diagnosis of middle ear disease, such as high-jugular bulb, congenital cholesteatoma, and ossicular disruption. However, certain diagnoses are confirmed through exploratory tympanotomy. There are few noninvasive methods available to observe the middle ear. The purpose of this study was to investigate the effect of glycerol as a refractive index matching material and an infrared (IR) camera system for extratympanic observation. 30% glycerol was used as a refractive index matching material in five fresh cadavers. Each material was divided into four subgroups; GN (glycerol no) group, GO (glycerol out) group, GI (glycerol in) group, and GB (glycerol both) group. A printed letter and middle ear structures on the inside tympanic membrane were observed using a visible and IR ray camera system. In the GB group, there were marked a transilluminated letter or an ossicle on the inside tympanic membrane. In particular, a footplate of stapes was even transilluminated using the IR camera system in the GB group. This method can be useful in the diagnosis of diseases of the middle ear if it is clinically applied through further studies.

Activation of the IL-6/JAK/STAT3 signaling pathway in human middle ear cholesteatoma epithelium.

Interleukin-6 (IL-6) is one of the most important cytokines which has been shown to play a critical role in the pathogenesis of cholesteatoma. In this study, we aimed to investigate the expression of interleukin-6 (IL-6) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in middle ear cholesteatoma epithelium in an effort to determine the role of IL-6/JAK/STAT3 signaling pathway in the pathogenesis of cholesteatoma. Immunohistochemistry was used to examine the expression of IL-6 and p-STAT3 in 25 human middle ear cholesteatoma samples and 15 normal external auditory canal (EAC) epithelium specimens. We also analyzed the relation of IL-6 and p-STAT3 expression levels to the degree of bone destruction in cholesteatoma. We found that the expression of IL-6 and p-STAT3 were significantly higher in cholesteatoma epithelium than in normal EAC epithelium (p<0.05). In cholesteatoma epithelium, a significant positive association was observed between IL-6 and p-STAT3 expression (p<0.05). However, no significant relationships were observed between the degree of bone destruction and the levels of IL-6 and p-STAT3 expression (p>0.05). To conclude, our results support the concept that IL-6/JAK/STAT3 signaling pathway is active and may play an important role in the mechanisms of epithelial hyper-proliferation responsible for cholesteatoma.

In situ tissue engineering with synthetic self-assembling peptide nanofiber scaffolds, PuraMatrix, for mucosal regeneration in the rat middle-ear.

Middle-ear mucosa maintains middle-ear pressure. However, the majority of surgical cases exhibit inadequate middle-ear mucosal regeneration, and mucosal transplantation is necessary in such cases. The aim of the present study was to assess the feasibility of transplantation of isolated mucosal cells encapsulated within synthetic self-assembling peptide nanofiber scaffolds using PuraMatrix, which has been successfully used as scaffolding in tissue engineering, for the repair of damaged middle-ear. Middle-ear bullae with mucosa were removed from Sprague Dawley (SD) transgenic rats, transfected with enhanced green fluorescent protein (EGFP) transgene and excised into small pieces, then cultured up to the third passage. After surgical elimination of middle-ear mucosa in SD recipient rats, donor cells were encapsulated within PuraMatrix and transplanted into these immunosuppressed rats. Primary cultured cells were positive for pancytokeratin but not for vimentin, and retained the character of middle-ear epithelial cells. A high proportion of EGFP-expressing cells were found in the recipient middle-ear after transplantation with PuraMatrix, but not without PuraMatrix. These cells retained normal morphology and function, as confirmed by histological examination, immunohistochemistry, and electron microscopy, and multiplied to form new epithelial and subepithelial layers together with basement membrane. The present study demonstrated the feasibility of transplantation of cultured middle-ear mucosal epithelial cells encapsulated within PuraMatrix for regeneration of surgically eliminated mucosa of the middle-ear in SD rats.

Role of the alternative and classical complement activation pathway in complement mediated killing against Streptococcus pneumoniae colony opacity variants during acute pneumococcal otitis media in mice.

There is considerable evidence that phase variation among transparent and opaque colony phenotypes of Streptococcus pneumoniae (Spn) plays an important role in the pneumococcal adherence and invasion. The current study was designed to investigate the interactions of the opacity phenotype variants of Spn with specific complement pathway activation in a mouse model of acute otitis media (AOM). Although the opaque colony phenotype was expected to be more resistant to complement mediated killing compared to the transparent Spn variant, we discovered that C3b deposition on the transparent Spn is, in large part, dependent on the alternative pathway activation. There were no significant differences in resistance to complement mediated opsonophagocytosis between the two variants in factor B deficient mice. In addition, an in vitro study demonstrated that significantly more C4b-binding protein (C4BP) (the classical pathway inhibitor) and factor H (FH) (the alternative pathway inhibitor) bound to the transparent strain compared with the opaque one. Our data suggest that the difference in the relative virulence of Spn opacity phenotypes is associated with its ability to evade complement-mediated opsonophagocytosis in a mouse model of pneumococcal AOM.

Aggressive low grade middle ear adenocarcinoma with multiple recurrences: a case report.

BACKGROUND: Primary tumours of the middle ear are much less commonly encountered in clinical practice than non neoplastic lesions. Middle ear adenocarcinoma is a very rare, locally invasive neoplasm assumed to arise from the middle ear mucosa. Because the natural course and clinical behavior of this neoplasm are far from established, the sporadic reports of such cases continue to provide basis for better understanding. CASE DESCRIPTION: A case of low grade adenocarcinoma of the middle ear is described in details with regard to its clinical presentation, radiological findings, histopathological, immunohistochemical and ultrastructural findings. The tumour recurred four times.

Altered expression of middle and inner ear cytokines in mouse otitis media.

OBJECTIVES/HYPOTHESIS: The inner ear is at risk for sensorineural hearing loss in both acute and chronic otitis media (OM), but the mechanisms underlying sensorineural hearing loss are unknown. Previous gene expression array studies have shown that cytokine genes might be upregulated in the cochleas of mice with acute and chronic OM. This finding implies that the inner ear could manifest a direct inflammatory response to OM that may cause sensorineural damage. Therefore, to better understand inner ear cytokine gene expression during OM, quantitative real-time polymerase chain reaction and immunohistochemistry were used in mouse models to evaluate middle and inner ear inflammatory and remodeling cytokines. STUDY DESIGN: Basic science experiment. METHODS: An acute OM model was created in Balb/c mice by a transtympanic injection of Streptococcus pneumoniae in one ear; the other ear was used as a control. C3H/HeJ mice were screened for unilateral chronic OM, with the noninfected ear serving as a control. RESULTS: Both acute and chronic OM caused both the middle ear and inner tissues in these two mouse models to overexpress numerous cytokine genes related to tissue remodeling (tumor necrosis factor-α, bone morphogenetic proteins, fibroblast growth factors) and angiogenesis (vascular endothelial growth factor), as well as inflammatory cell proliferation (interleukin [IL]-1α,ß, IL-2, IL-6). Immunohistochemistry confirmed that both the middle ear and inner ear tissues expressed these cytokines. CONCLUSIONS: Cochlear tissues are capable of expressing cytokine mRNA that contributes to the inflammation and remodeling that occur in association with middle ear disease. This provides a potential molecular basis for the transient and permanent sensorineural hearing loss often reported with acute and chronic OM.

Partial characterization of normal and Haemophilus influenzae-infected mucosal complementary DNA libraries in chinchilla middle ear mucosa.

OBJECTIVES: We sought to construct and partially characterize complementary DNA (cDNA) libraries prepared from the middle ear mucosa (MEM) of chinchillas to better understand pathogenic aspects of infection and inflammation, particularly with respect to leukotriene biogenesis and response. METHODS: Chinchilla MEM was harvested from controls and after middle ear inoculation with nontypeable Haemophilus influenzae. RNA was extracted to generate cDNA libraries. Randomly selected clones were subjected to sequence analysis to characterize the libraries and to provide DNA sequence for phylogenetic analyses. Reverse transcription-polymerase chain reaction of the RNA pools was used to generate cDNA sequences corresponding to genes associated with leukotriene biosynthesis and metabolism. RESULTS: Sequence analysis of 921 randomly selected clones from the uninfected MEM cDNA library produced approximately 250,000 nucleotides of almost entirely novel sequence data. Searches of the GenBank database with the Basic Local Alignment Search Tool provided for identification of 515 unique genes expressed in the MEM and not previously described in chinchillas. In almost all cases, the chinchilla cDNA sequences displayed much greater homology to human or other primate genes than with rodent species. Genes associated with leukotriene metabolism were present in both normal and infected MEM. CONCLUSIONS: Based on both phylogenetic comparisons and gene expression similarities with humans, chinchilla MEM appears to be an excellent model for the study of middle ear inflammation and infection. The higher degree of sequence similarity between chinchillas and humans compared to chinchillas and rodents was unexpected. The cDNA libraries from normal and infected chinchilla MEM will serve as useful molecular tools in the study of otitis media and should yield important information with respect to middle ear pathogenesis.

The incidence of Streptococcus pneumoniae otitis media is affected by the polymicrobial environment particularly Moraxella catarrhalis in a mouse nasal colonisation model.

Otitis media (OM) is a highly prevalent paediatric disease with both bacterial and viral triggers of infection. This study has investigated how combinations of bacteria associated with nasal colonisation and the occurrence and absence of viral infection (Sendai virus) induce OM in a mouse nasal colonisation model. The respiratory virus significantly contributed to bacterial OM for all bacterial combinations (p<0.001). Streptococcus pneumoniae consistently dominated as the causative bacterium of OM and when co-infected with S. pneumoniae, Moraxella catarrhalis more significantly affected pneumococcal OM than did non-typeable Haemophilus influenzae (p<0.001) by increasing the incidence rate, infection bacterial load and duration of infection. Nitric oxide levels in the middle ear, an indicator of inflammation, peaked at day 3 in single bacterium groups, but at day 1 in mixed bacterial groups and was produced in all bacteria inoculated groups even in the absence of viable bacterial recovery. Phagocytic cells were recruited rapidly to the ear following nasal inoculation but over time their numbers did not correlate with persistence of bacterial infection. The study has shown that the composition of bacteria in the nasal cavity and respiratory viral infection significantly affected the OM incidence rate, duration of infection and bacterial load (severity).

Prediction of gastroesophageal reflux in otitis media with effusion in adults.

CONCLUSIONS: The measurement of pepsinogen I (PGI) in middle-ear effusions (MEEs) and a questionnaire on the frequency symptoms of gastroesophageal reflux (GER) disease are tools that can be used to screen for the existence of GER. OBJECTIVE: To seek methods that would be beneficial as a screen for the presence of GER among adult patients with OME. MATERIALS AND METHODS: Fifty-eight adult outpatients with OME were asked to answer a questionnaire of the frequency scale for symptoms of GER disease. Samples of MEEs were obtained from each subject and were measured for concentrations of PGI and PGII. Some patients were followed up after being treated with a proton pump inhibitor. RESULTS: The percentage of patients with high PGI concentrations in their MEEs was higher in those with GER-related symptoms than in those without GER-related symptoms. Moreover, OME was present bilaterally in a higher percentage of patients with GER-related symptoms. There were patients in whom PGI levels decreased after receiving treatment for GER.

Spontaneous development of otitis media in plasminogen-deficient mice.

Inflammatory conditions of the ear, otitis media, are one of the most common disease entities in children. In this study, the role of the plasminogen (plg)/plasmin system for the spontaneous development of chronic otitis media was investigated by the analysis of plg-deficient mice. Whereas essentially all of the wild-type control mice kept a healthy status of the middle ear, all the plg-deficient mice gradually developed chronic otitis media with various degrees of inflammatory changes during an 18-week observation period. Five bacterial strains were identified in materials obtained from the middle ear cavities of six plg-deficient mice. Morphological studies revealed the formation of an amorphous mass tissue and inflammatory changes in the middle ears of plg-deficient mice. Immunohistochemical studies further indicate a mass infiltration of neutrophils and macrophages as well as the presence of T and B cells in the middle ear mucosa of these mice. Extensive fibrin deposition and an abnormal keratin formation were also observed in the tympanic membrane, the middle ear cavity and external ear canal in these mice. These results suggest that plg plays an essential role in protecting against the spontaneous development of chronic otitis media. Our findings also suggest the possibility of using plg for clinical therapy of certain types of otitis media.

Eosinophil chemoattractants in the middle ear of patients with eosinophilic otitis media.

BACKGROUND: Patients with intractable otitis media associated with bronchial asthma have an extensive accumulation of eosinophils in the effusion and mucosa of the middle ear; this condition is called eosinophilic otitis media (EOM). It remained to be determined how eosinophils accumulate in the middle ear. OBJECTIVES: To clarify the pathogenesis of middle ear diseases, we measured the concentration of eosinophil chemoattractants in middle ear effusion (MEE), and carried out immunohistochemical studies of middle ear mucosa specimens to demonstrate the expression of eosinophil chemoattractants. METHODS: Middle ear effusion samples were obtained from 15 EOM patients with bronchial asthma and from six controls for the measurement of eosinophil cationic protein (ECP), IL-5, eotaxin and regulated on activation, normal T expressed and secreted concentrations. Middle ear mucosa samples were also taken from 14 EOM patients and 16 controls for immunohistochemical study. In 10 EOM patients, the numbers of immunoreactive cells as well as apoptotic cells were determined before and after the topical application of triamcinolone acetonide into the middle ear. RESULTS: In EOM, significantly higher ECP and IL-5 concentrations were detected in MEE than in serum, and ECP, IL-5 and eotaxin concentrations in MEE were higher in the EOM patients than in the controls. ECP concentration positively correlated with that of IL-5. Immunohistochemically, the numbers of cells positive for EG2 and ecalectin were significantly higher in the EOM patients than in the controls. After the topical application of triamcinolone acetonide, the numbers of infiltrating cells and immunoreactive cells distinctly decreased, whereas the number of apoptotic cells significantly increased. CONCLUSION: In EOM, locally produced IL-5 may play a crucial role in the accumulation of eosinophils in the middle ear. Chemokines such as ecalectin and eotaxin are also produced in the middle ear, and help activate and enhance the survival of eosinophils to induce the intractable condition in the middle ear. The topical application of triamcinolone acetonide induces the apoptosis of not only eosinophils but also eosinophil chemoattractant-producing cells, thereby improving the middle ear condition.

On morphometric measurement of oxygen diffusing capacity in middle ear gas exchange.

An accurate mathematical model of transmucosal gas exchange is prerequisite to understanding middle ear (ME) physiology. Current models require experimentally measured gas species time constants for all extant conditions as input parameters. However, studies on pulmonary gas exchange have shown that a morphometric model that incorporates more fundamental physiochemical and anatomic parameters accurately simulates transport from which the species time constants can be derived for all extant conditions. Here, we implemented a variant of that model for ME gas exchange that requires the measurement of diffusional length (tau) for the ME mucosa. That measure contributes to the mucosal diffusing capacity and reflects the resistance to gas flow between air space and capillary. Two methods for measuring tau have been proposed: linear distance between the air-mucosal boundary and capillary and the harmonic mean of all contributing pathway lengths. Oxygen diffusing capacity was calculated for different ME mucosal geometries by using the two tau measures, and the results were compared with those predicted by a detailed, two-dimensional finite element analysis. Predictive accuracy was improved by incorporating the harmonic tau measure, which captures important information regarding variations in capillary shape and distribution. However, compared with the oxygen diffusing capacity derived from the finite element analysis, both measures yielded nonlinear, positively biased estimates. The morphometric techniques underestimate diffusion length by failing to account for the curvilinear gas flow pathways predicted by the finite element model.