Middle Ear Mucosa Research Articles

Immunohistochemical and qPCR Detection of SARS-CoV-2 in the Human Middle Ear Versus the Nasal Cavity: Case Series

Viral infections have already been implicated with otitis media and sudden sensorineural hearing loss. However, the pathophysiology of COVID-19 as it relates to otologic disorders is not well-defined. With the spread of SARS-CoV-2, it is important to evaluate its colonization of middle ear mucosa. Middle ear and nasal tissue samples for quantitative RT-PCR and histologic evaluations were obtained from post-mortem COVID-19 patients and non-diseased control patients. Here we present evidence that SARS-CoV-2 colonizes the middle ear epithelium and co-localizes with the primary viral receptor, angiotensin-converting enzyme 2 (ACE2). Both middle ear and nasal epithelial cells show relatively high expression of ACE2, required for SARS-CoV-2 entry. The epithelial cell adhesion molecule (EpCAM) was use as a biomarker of epithelia. Furthermore, we found that the viral load in the middle ear is lower than that present in the nasal cavity.

A child’s mysterious ear

<p>Foreign body in ear is an emergency encountered by an otolaryngologist and if not removed it can lead to serious complications. Most commonly foreign body in ear is lodged in external auditory canal while it’s rare to find it in middle ear. We report a case of foreign body in the middle ear in a 3-year-old child who presented to us with chronic discharging ear who was then suspected to be unsafe ear and so was taken up for exploration under microscope. A pink polypoidal mass arising from middle ear mucosa was found and following its removal- to our surprise; a blackish rubbery debris filling the middle ear cavity and attic area along with embedded foreign body was extracted. We conclude that pediatric patients with chronic ear discharge not responding to antibiotics should raise a suspicion of FB in the middle ear and explored timely.</p>

A retrospective study on middle ear risk indices in analysing the post-operative outcome following tympanoplasty

<p class="abstract"><strong>Background:</strong> Chronic otitis media is a highly prevalent disease of middle ear. As tympanoplasty plays an important role in management of otitis media it is important to predict the outcome of surgery and give proper counselling to the patient. The objective of this study was to evaluate the effectiveness of Middle ear risk index (MERI) in determining postoperative graft uptake and postoperative air bone gap closure following tympanoplasty.</p><p class="abstract"><strong>Methods:</strong> This was a retrospective study conducted to find the correlation between MERI and the result of tympanoplasty outcome and post-operative hearing gain. Ninety-six subjects who underwent tympanoplasty for chronic otitis media were included in the study. MERI score was calculated and was compared with postoperative graft uptake and audiogram. </p><p class="abstract"><strong>Results:</strong> In this study there was no statistical difference in graft uptake between the MERI categories. There was statistically significant decrease in postoperative air bone gap closure in both mild and moderate categories. Other prognostic factors associated with a favourable outcome were healthy middle ear mucosa and absence of smoking.</p><p class="abstract"><strong>Conclusions:</strong> MERI did not have a direct impact on the outcome of surgery in terms of graft uptake and hearing results. However certain factors like Belluci’s criteria and smoking had an impact on the outcome. Hence MERI can be used for pre-operative counselling of the patients.</p>

Toll-Like Receptors: Expression and Roles in Otitis Media.

Otitis media is mainly caused by upper respiratory tract infection and eustachian tube dysfunction. If external upper respiratory tract infection is not detected early in the middle ear, or an appropriate immune response does not occur, otitis media can become a chronic state or complications may occur. Therefore, given the important role of Toll-like receptors (TLRs) in the early response to external antigens, we surveyed the role of TLRs in otitis media. To summarize the role of TLR in otitis media, we reviewed articles on the expression of TLRs in acute otitis media (AOM), otitis media with effusion (OME), chronic otitis media (COM) with cholesteatoma, and COM without cholesteatoma. Many studies showed that TLRs 1–10 are expressed in AOM, OME, COM with cholesteatoma, and COM without cholesteatoma. TLR expression in the normal middle ear mucosa is absent or weak, but is increased in inflammatory fluid of AOM, effusion of OME, and granulation tissue and cholesteatoma of COM. In addition, TLRs show increased or decreased expression depending on the presence or absence of bacteria, recurrence of disease, tissue type, and repeated surgery. In conclusion, expression of TLRs is associated with otitis media. Inappropriate TLR expression, or delayed or absent induction, are associated with the occurrence, recurrence, chronicization, and complications of otitis media. Therefore, TLRs are very important in otitis media and closely related to its etiology.

Effect of γ-secretase inhibitor on middle ear ultrastructures in ovalbumin-mediated otitis media with effusion in rats

Objective: To study the effect of the inhibitor of Notch signaling pathway-γ-secretase inhibitor DAPT on the ultrastructures of middle ear in the ovalbumin (OVA)-mediated allergic OME in vivo. Methods: Male Sprague-Dawley (SD) rats, weighing 250-300 g, were completely and randomly divided into three groups (5 rats, 10 ears in each group):(1)Control group(2)OME group(3)OME+DAPT group. Rats in the OME group underwent systemic and local sensitization by intraperitoneal and intratympanic injection of ovalbumin to make the model of OVA-induced OME. Rats in the control group were sensitized with PBS. On the basis of establishing the OME model, OME+DAPT group were intraperitoneal injected with DAPT (10 mg/kg) for seven consecutive days and were administered before intratympanic injection of ovalbumin. After the model was successfully established, endoscopy,H&E staining and scanning electron microscopy were used to study the histology and mucous-ciliary ultrastructures of the non-ciliated and ciliated mucosa in the middle ear of each group. One-way ANOVA and Tukey methods were used for statistical analysis. Results: H&E staining showed that the three groups had statistically significant differences in submucosal thickness both in non-ciliated and ciliated regions (non-ciliated area:(6.83±1.47)μm, (38.58±9.57)μm, (32.17±11.89)μm, respectively. F=107.9;cilia area:(26.69±3.22)μm, (30.41±6.75)μm, (26.76±4.06)μm, respectively. F=5.62,both P<0.01). The thickness of the submucosa in the non-ciliated area and the cilia area of the OME group were significantly thicker than that of control group (F=42.08 and 4.40,both P<0.05); the thickness of the non-ciliated area and the ciliated area in OME+DAPT group were reduced compared to OME group(F=1.55 and 2.77,both P<0.05). Scanning electron microscopy showed that the array of cilia on the middle ear mucosa was disorderly arranged and inversed, this phenomenon was relieved in the OME+DAPT group. The number of goblet cells in the control group, OME group, and OME+DAPT group were 9.87±1.92; 15.67±5.77; 10.33±1.99 respectively and the difference between them was statistically significant (F=11.43, P<0.01). The number of goblet cells in the OME group were significantly higher than those in the control group (F=9.00,P<0.01) and the number of goblet cells in the OME+DAPT group were decreased compared to those of OME group (F=8.41, P<0.01). Conclusions: The study demonstrates the pathological changes of the ultrastructure in middle ear in OVA-induced OME and the effect of the γ-secretase inhibitor on it. In OME group, the cilia are disorderly arranged and inversed, the number of goblet cell is increased and they are swelled which suggest the hypersecretion of the mucus. DAPT can regulate OVA-induced allergic inflammation and relieve pathological changes of ultrastructure in middle ear mucociliary transport system through alleviating submucosal inflammation, reducing the hypersecretion of goblet cell and the morphological damage of cilia through the Notch signaling pathway.

Middle Ear "Adenoma": a Neuroendocrine Tumor with Predominant L Cell Differentiation.

This morphological and immunohistochemical study demonstrates that tumors currently known as "middle ear adenomas" are truly well-differentiated epithelial neuroendocrine tumors (NETs) composed of cells comparable to normal intestinal L cells, and therefore, these tumors resemble hindgut NETs. These tumors show consistent expression of glucagon, pancreatic polypeptide, PYY, and the transcription factor SATB2, as well as generic neuroendocrine markers and keratins. The same L cell markers are expressed by cells within the normal middle ear epithelium. These markers define a valuable immunohistochemical profile that can be used for differential diagnosis of middle ear neoplasms, particularly in distinguishing epithelial NETs from paragangliomas. The discovery of neuroendocrine cells expressing the same markers in non-neoplastic middle ear mucosa opens new areas of investigation into the physiology of the normal middle ear and the pathophysiology of middle ear disorders.

Microbiological investigation of samples collected from healthy middle ears during cochlear implant surgery

This study aimed to investigate the bacteriome in microscopically healthy middle ear mucosa using Next-generation sequencing (NGS) technology. A total of 60 middle ear washing fluids of pediatric and adult were obtained from 47 patients (35 children and 12 adults). Both children and adults with normal middle ears harbored diverse bacteriome. Seventeen different genera with a mean relative abundance of more than 1% were detected in all samples. Both in adult and children, the most abundant genus was Propionibacterium followed by Streptococcus, Staphylococcus, and Ralstonia. The species Propionibacterium acnes and Corynebacterium tuberculostearicum were significantly more abundant in the adult group. Although there were differences in the prevalence and relative abundance of some bacteria observed from adult and child groups, no specific genus or species was detected only in children or adults.

Type I Tympanoplasty: surgical success and prognostic factors

ObjectivesTo evaluate success rate of type I tympanoplasty in adults and to investigate the importance of selected prognostic factors on graft uptake. Material and methodsRetrospective medical chart review of 155 patients who underwent Type I Tympanoplasty, in our department, from January 2013 to December 2017. Graft uptake rate was evaluated and the effects of prognostic factors on surgical outcome such as sex, smoking and otological surgery history, status of the contralateral ear, size and location of the perforation, middle ear mucosa status, surgical approach and graft material. Preoperative and postoperative audiometric data were collected, and the functional success was determined. ResultsThe overall surgical anatomical success rate was 75%. Analysis of the selected variables, identified as independent prognostic factors of anatomical unsuccess (95% CI): smoking (OR=3.29, p<.01), middle ear tympanosclerosis (OR=2.96; p=.04). Perforations above 50% of the tympanic membrane area had a borderline effect on graft uptake (p=.05). There was a significative improvement in the average air conduction thresholds of 7.44dB and an ABG closure rate at 10dB and 20dB was achieved in 47% and 84.5%, respectively. Patients who received temporalis fascia graft had similar hearing gain compared to patients who underwent cartilage tympanoplasty (7.7 vs. 7.3dB, p=.79). ConclusionType I tympanoplasty is an effective and safe procedure with a high anatomical success rate in the treatment of mucosal COM. Poorer outcomes were found in patients with smoking habits, in those with tympanosclerosis of middle ear mucosa and in larger perforations. These prognostic factors should be considered in surgical planning and patients should be advised to quit smoking. Tympanoplasty with cartilage graft had a hearing outcome comparable to temporalis fascia graft and should be considered in high-risk patients.

Application of artificial intelligence using a convolutional neural network for detecting cholesteatoma in endoscopic enhanced images

ObjectiveWe examined whether artificial intelligence (AI) used with the novel digital image enhancement system modalities (CLARA+CHROMA, SPECTRA A, and SPECTRA B) could distinguish the cholesteatoma matrix, cholesteatoma debris, and normal middle ear mucosa, and observe the middle ear cavity during middle ear cholesteatoma surgery. MethodsA convolutional neural network (CNN) was trained with a set of images chosen by an otologist. To evaluate the diagnostic accuracy of the constructed CNN, an independent test data set of middle ear images was collected from 14 consecutive patients with 26 cholesteatoma matrix lesions, who underwent transcanal endoscopic ear surgery at a single hospital from August 2018 to September 2019. The final test data set included 58 total images, with 1‒5 images from each modality for each case. ResultsThe CNN required only 10 s to analyze more than 58 test images. Using SPECTRA A and SPECTRA B, the CNN correctly diagnosed 15 and 15 of 26 cholesteatoma matrix lesions, with a sensitivity of 34.6% and 42.3%, and with a specificity of 81.3% and 87.5%, respectively. ConclusionOur preliminary study revealed that AI and novel imaging modalities are potentially useful tools for identifying and visualizing the cholesteatoma matrix during endoscopic ear surgery. The diagnostic ability of the CNN is not yet appropriate for implementation in daily clinical practice, based on our study findings. However, in the future, these techniques and AI tools could help to reduce the burden on surgeons and will facilitate telemedicine in remote and rural areas, as well as in developing countries where the number of surgeons is limited.

Covid-19 and Ear Surgery: Treatment Strategies and Triage during the Post-lockdown Period

The accumulated disease burden during lockdown period, due to postponement of regular surgeries, is expected to put additional pressure on surgeons during the post-lockdown period. Due to the contagious nature of SARS-CoV-2 and its suspected presence in middle ear mucosa and mastoid, Ear surgeons are bound to face a challenging situation in present times as well as in times to come. Through this article we aim to streamline fresh management strategies particularly for the post-lockdown period keeping in mind that immunity after vaccination may take a few months to develop due to various factors discussed in the article. The ENT Cochrane, Pubmed and Web of Science databases were searched extensively using the terms ‘Covid-19 and SARS-CoV-2 in conjunction with Ear surgery and Otology. Data collected from these, put together with our experience helped us in putting forward fresh management strategies to deal with the current situation being experienced worldwide. To reduce the risk of infection to the healthcare staff, we have suggested a new triage strategy for ear surgeries to reduce the accumulated disease burden in the post-lockdown period until immunity by vaccination develops amongst a good number of Ear surgeons. Also we have put forward certain operating guidelines that might prove helpful for the Ear surgeon during these times. Fresh Triage guidelines mentioned in this article are particularly meant to help ear surgeons reduce the accumulated disease burden in the post lockdown-period with ease and efficacy. Since ear surgery poses a risk of infection to the healthcare workers, specific guidelines pertaining to ear surgery during the pandemic are mentioned in detail which in our opinion can be of immense help to all the healthcare professionals involved in ear procedures till the time the vaccine is administered on a large scale.

The role of Helicobacter pylori and gastroesophageal reflux disease in otitis media with effusion and evaluation of MUC4, MUC5B mucin genes and inflammatory cytokines in guinea pig middle ears

Objectives: This study aims to investigate the role of Helicobacter pylori (H. pylori) and gastroesophageal reflux disease (GERD) in otitis media with effusion (OME) and to examine the MUC4, MUC5B mucin genes in the guinea pig middle ears to analyze the inflammatory cytokines including tumor necrosis factor-alpha (TNF-a), interleukin (IL)-1beta (IL-1b), and IL-8. Patients and Methods: This study was conducted using eight guinea pigs. In the experimental group, H. pylori ATCC strain culture was injected transtympanically with microscopic guidance. The animals in the control group were injected with phosphate buffered saline (PBS) solution transtympanically. At 12, 24, 48, and 168 h after the injection, transtympanic PBS solution injection and aspiration of the middle ear were applied to all animals. After decapitation, the samples were taken. Results: In the histopathological examination, grading according to the degree of inflammation showed no statistically significant difference between the two groups (p&gt;0.05). No statistically significant difference was determined in the analysis results of MUC4 and MUC5B genes in the middle ears of the two groups (p&gt;0.05), the right and left ear values of IL-8, IL-1b, and TNF-a (p=0.999, p=0.610, and p=0.691, respectively). Conclusion: Based on our study results, there was no relationship between H. pylori injection in the middle ear and the histopathological changes of the middle ear mucosa. The results of the analysis of MU

IgG4 Expression in Patients with Eosinophilic Otitis Media

Objective: Eosinophilic otitis media (EOM) is an intractable middle ear disease recognized by an eosinophil enriched middle ear effusion and mucosa. Although precise pathogenesis of EOM remains unclear, it is characterized by type 2 inflammation. Since IgG4 is an IgG subclass induced by type 2 cytokines such as IL-4 and IL-13, we sought to characterize and compare local IgG4 expression in patients with and without EOM. Methods: Twelve patients with bilateral profound hearing loss, 9 of which underwent a cochlear implant surgery, were enrolled in this study (6 with EOM and 6 without EOM). The surgical specimens were harvested during surgery and were subjected to IgG4 immunostaining. Result: The middle ear mucosa showed the presence of a large number of IgG4-positive cells in patients with EOM, which was significantly higher than that in patients without EOM. Conclusion: Local IgG4 expression was observed in patients with EOM in comparison to those without EOM, suggesting that IgG4 contributes to EOM pathogenesis.

Over-Underlay technique of myringoplasty.

Objective: To observe the success rate of Over-underlay technique of myringoplasty in patients with inactive tubo-tympanic type of CSOM. Study Design: Descriptive, Observational study. Setting: ENT Department Fauji Foundation Hospital Rawalpindi. Period: December 2018 to December 2019. Material &amp; Methods: A total of 80 patients with inactive tubo-tympanic type of CSOM, from both genders, within age range of 15-45 years, having pure conductive hearing loss with an Air-Bone gap of not less than 15 dB were selected by convenient sampling technique. Patients having an active ear disease or previous history of ear surgery, an active sinus or URT disease, or any comorbidity were excluded from the study. Complete general and head-neck examination was done after taking history. Patients’ affected ears were examined under surgical microscope to see the drum perforation, condition of middle ear mucosa and the status of the ossicles. Hearing assessment was done by Pure Tone Audiometry through both air and bone conduction. Temporalis fascia graft myringoplasty was done in all these patients by over-underlay technique, and they were discharged on 5th post-operative day, and were followed up in ENT OPD after 3 weeks. Status of graft was seen under surgical microscope after removing the BIPP. After three months the patients were reviewed for graft status and hearing assessment. Successful outcome was taken as those patients in whom graft uptake was successful with complete closure of perforation, and secondly, closure of the Air-Bone gap by at least 10 dB. Data was analyzed by SPSS 19. Results: Mean age of the patients (n = 80) was found to be 30.8 Years. Gender distribution showed 57 (71.25%) Males and 23 (28.75%) Females with a M:F ratio of 2.5:1. Success rate was found significantly better among younger aged males. Graft uptake was successful in 74 (92.5%) of the patients. With respect to closure of A-B gap, post-operative mean difference in Air-Bone gap was found to be 9.6 dB ± 3.9 SD as compared to preoperative mean A-B gap of 28.5 dB ± 4.2 SD, thus a closure of A-B gap by 18.9 dB ± 2.4 SD. Conclusion: Over-underlay technique is found to be a successful technique for myringoplasty in terms of graft uptake and improvement in hearing thresholds in the patients with inactive tubo-tympanic type of CSOM.

The expression of VEGF and VEGFR in endotoxin induced otitis media with effusion in rats

ObjectiveTo investigate the expression and correlation of vascular endothelial growth factor (VEGF) and its receptor with hypoxia-inducible factor-1 α (HIF-1 α) in otitis media with effusion (OME). MethodsA rat model of OME was induced by injection of lipopolysaccharide (LPS) into the middle ear. Hematoxylin and eosin (HE) staining was used to observe the pathomorphological changes of the tympanic cavity in the middle ear of rats. Immunohistochemistry (IHC), western blotting and RT-qPCR were used to determine the mRNA and protein expression of VEGF, VEGFR-1, VEGFR-2 and HIF-1α in mucosa of tympanic cavity mucosa, respectively. ResultsIn the OME group, the epithelial space of the middle ear mucosa was significantly thickened and infiltration of a large number of inflammatory cells was found on postoperative day (POD), and the otitis media basically subsided 2 weeks after operation. VEGF mRNA expression was significantly increased on POD 1, and its protein expression peaked on POD 3. HIF-1α mRNA expression was significantly increased and peaked on POD 1, while its protein expression began to increase on POD 3 and was significantly expressed in the middle ear mucosal epithelium. HIF-1α mRNA showed a positive correlation with VEGF mRNA and VEGFR-1 mRNA expression. ConclusionVEGF mainly plays a role in the acute phase of OME, and it is abundantly expressed mediated by HIF-1α. And then it play a role in vasodilatation and increase of vascular permeability, thus promoting the generation of middle ear effusion.

Comparison of Medial Underlay and Lateral Underlay Endoscopic Type I Tympanoplasty for Anterior Perforations of the Tympanic Membrane.

To compare the outcomes of medial and lateral underlay endoscopic type I tympanoplasty for anterior tympanic membrane (TM) perforations. Retrospective chart review. Tertiary care academic referral center. Patients who were diagnosed with either chronic otitis media with dry and stable anterior TM perforations or traumatic anterior TM perforations and underwent endoscopic type I tympanoplasty between 2017 and 2019. Medial or lateral underlay type I endoscopic tympanoplasty. Patient demographics, size, and location of TM perforation, graft success rate, and hearing outcome. Of the 170 patients, 68 and 102 patients underwent the medial and lateral underlay techniques, respectively. Patient demographics were not significantly different between groups, except the middle ear mucosa status. Graft success rates were significantly different between groups regardless of the perforation size (85.3 and 95.1%, p < 0.001). The lateral underlay group had a significantly better outcome (p < 0.001) when anterior superior quadrant TM perforation was included than the medial underlay group (p = 0.552). Hearing outcomes did not significantly differ between groups, but a significant audiological improvement was observed in both groups (p < 0.05). Lateral underlay type I endoscopic tympanoplasty can be challenging as it requires dissection of the malleus. However, the lateral underlay group had a high graft success rate without sensorineural hearing loss in the repair of anterior TM perforations. Thus, lateral underlay type I endoscopic tympanoplasty should be considered for repairing anterior TM perforations, especially when the anterior superior quadrant is involved.

Descriptive study of various bacterial flora in chronic otitis media

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Chronic otitis media (COM) is the inflammation of the middle ear, which is characterised by ear discharge due to tympanic membrane perforation, at least for over a month. The inflammation is due to the underlying infection, due to which the middle ear mucosa gets inflamed, leading to discharge and eventual perforation of the tympanic membrane. The aim of the study was to study the microbial flora and its culture and sensitivity from ear discharge in chronic otitis media.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; Total of 100 ears with either mucosal COM or squamosal COM were included in this study. Patients coming to the outpatient department (OPD) with discharging ear were subjected to aural suctioning/cleaning with the use of bulls eye lamp. After cleaning the external auditory canal, sterile aural speculum were introduced into the EAC, creating a sterile conduit. Following this, middle ear discharge or the discharge around the tympanic membrane was collected using sterile cotton swabs and sent for laboratory within half an hour for mycological and bacteriological study.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results: &lt;/strong&gt;Majority of patients were in an age group of 10-20 years, followed by age group of 21-30 years. The male to female ratio was 4.7:5.3. Out of the 100 swabs sent for culture and sensitivity, 6 swabs had no growth whereas &lt;em&gt;Pseudomonas aeroginosa &lt;/em&gt;was the highest isolated organism (36 swabs), followed by &lt;em&gt;Proteus mirabilis &lt;/em&gt;(23 swabs). Aerobic infection was the commonest, isolated in 47.9% of culture positive swabs. Polymyxin B was the most sensitive antibiotic, whereas cefotaxime was the most resistant antibiotic.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; &lt;em&gt;Pseudomonas aeruginosa &lt;/em&gt;and &lt;em&gt;Proteus mirabilis &lt;/em&gt;are the main bacteria isolated in mucosal COM. There is development of drug resistance in the majority of bacteria in chronic otitis media, due to excessive usage of antibiotics, making the treatment much difficult.&lt;/p&gt;

The Possible Role of Sclerostin in the Pathogenesis of Tympanosclerosis

Objective: The aim of this study was to investigate sclerostin (SOST) expression in a rat model of experimental tympanosclerosis (TS) and its possible role in the formation of TS. Materials and Methods: Thirty-four SD rats were randomly divided into 2 groups: experimental group (n = 17) and normal group (n = 17). The left tympanic cavities in the experimental group were inoculated with methicillin-resistant Staphylococcus aureus. The changes of tympanic membranes were examined and recorded under otoendoscope. Haematoxylin-eosin staining was adopted to detect the morphological changes in the tympanic membrane and middle ear mucosa. Immunohistochemistry and Western blot analysis were used to observe the expression of SOST, Wnt3a, β-catenin, and P-ERK1/2. Results: In the experimental group, sclerotic lesions were observed in 54.5% ears in the end of 6 weeks. Morphological changes such as mucosa incrassation, inflammatory cells infiltration, fibrous tissue proliferation, and interstitial tissue incrassation prominently appeared in the tympanic membrane and middle ear mucosa. SOST protein was mainly distributed in the cytoplasm of epithelial cells and gland cells, the expression of which increased significantly in the calcified experimental ears. In addition, expression levels of Wnt3a, β-catenin, and P-ERK1/2 increased significantly in the calcified group too. Conclusion: The upregulated expression level of SOST may be involved in the formation of TS, first, through the pro-phosphorylation of ERK1/2 in the inflammatory stage, and then through the enhancement of Wnt3a in the osteogenic stage.

Oral seeding and niche-adaptation of middle ear biofilms in health

The entrenched dogma of a sterile middle ear mucosa in health is incongruent with its periodic aeration and seeding with saliva aerosols. To test this, we sequenced 16S rRNA-V4 amplicons from otic secretions collected at the nasopharyngeal orifice of the tympanic tube and, as controls, oropharyngeal and buccal samples. The otic samples harbored a rich diversity of oral keystone genera and similar functional traits but were enriched in anaerobic genera in the Bacteroidetes (Prevotella and Alloprevotella), Fusobacteria (Fusobacterium and Leptotrichia) and Firmicutes (Veillonella) phyla. Facultative anaerobes in the Streptococcus genus were also abundant in the otic and oral samples but corresponded to distinct, and sometimes novel, cultivars, consistent with the ecological diversification of the oral migrants once in the middle ear microenvironment. Neutral community models also predicted a large contribution of oral dispersal to the otic communities and the positive selection of taxa better adapted to growth and reproduction under limited aeration. These results challenge the traditional view of a sterile middle ear in health and highlight hitherto unknown roles for oral dispersal and episodic ventilation in seeding and diversifying otic biofilms.

Expression of tumor necrosis factor Alpha, interleukin-1 and matrix metalloproteinase-9 and pathomorphological changes in acquired middle ear cholesteatoma

&amp;lt;p&amp;gt;Introduction. The inflammatory mediators play a central role in the pathogenesis of the inflammatory process of the middle ear and cholesteatoma from the aspect of initiating and maintaining the inflammatory response to infection and lesion. The aim of the study was to examine if the presence of acquired cholesteatoma could predict pathomorphological changes of the tympanic cavity mucosa in relation to the control tissue of the inflamed middle ear mucosa and to examine and compare the expression levels of tumor necrosis factor-alpha (TNF-a), interleukin-1 (IL-1) and matrix metalloproteinase 9 (MMP-9) with pathomorphological changes in the middle ear mucosa in chronic otitis media (COM), with and without acquired cholesteatoma (AC). Methods. The immunohistochemical study included 178 patients of both sexes, aged 5 to 75, who underwent microsurgical treatment of COM from 2015 to 2018. Patients were divided into two groups based on the presence or absence of AC of the middle ear: 97 with cholesteatoma (CCOM) and 81 without cholesteatoma (COM). Samples of the perimatrix of AC and inflamed middle ear mucosa were taken intraoperatively. The condition of the tympanic cavity mucosa was examined by otomicroscopy exploration intraoperatively. The expression levels of TNF-a, IL-1 and MMP-9 were determined by immunohistochemical analysis. Results. The difference in the percentage distribution of patients according to the condition of the tympanic cavity mucosa between both groups was statistically significant (p &amp;amp;lt;0.01) where in the COM group the highest frequency was 43.2% of patients with mucosal hypertrophy, and in the CCOM 56.7% with granulations. With highly positive expression of TNF-R2 and IL-1, a higher probability of the presence of mucosal hypertrophy and granulations can be expected, and with highly positive expression of MMP-9 the presence of granulations. Conclusion. Acquired middle ear cholesteatoma is a statistically significant predictor of the occurence of mucosal hypertrophy and granulations in the tympanic cavity in relation to the control tissue of the inflamed middle ear mucosa. The high expression of TNF-R2, IL-1 and MMP-9 shows a statistically significant association with the presence of granulations and mucosal hypertrophy in acquired middle ear cholesteatoma which may have clinical significance in the evaluation and prognosis of the disease.&amp;lt;/p&amp;gt;

Histopathological Effects of Boric Acid Solution on Middle Ear Mucosa in Guinea Pigs

Histopathological Effects of Boric Acid Solution on Middle Ear Mucosa in Guinea Pigs