Moo Kyun Park

Repair of large traumatic tympanic membrane perforation with a Steri-Strips patch.

Objective. To investigate the effects of the Steri-Strips patch (3M) on the treatment of large traumatic tympanic membrane perforations (TMP). Study Design. Prospective, randomized, controlled. Setting. Tertiary university hospital. Subjects and Methods. A randomized prospective analysis was performed between February 2009 and January 2011 for the treatment of traumatic TMP larger than 50% of the entire tympanic membrane. The results of closure rate, closure time, hearing gain, and rate of otorrhea between conservative observation, paper patching, and Steri-Strips patching groups were compared. Results. In total, 87 patients were analyzed in this study. The closure rates of the perforations in the Steri-Strips patching, paper patching, and observation groups were 93.3%, 84.2%, and 78.9%, respectively. There was no statistically significant difference in tympanic membrane closure rate between the 3 groups. The Steri-Strips technique decreased the need for repeat procedures. Overall, the Steri-Strips and paper patching groups showed shorter healing times compared with the observation group. However, there was an increased rate of otorrhea in the Steri-Strips group compared with the observation group. Conclusion. Steri-Strips patching reduced the healing time and need for repeat procedures in patients with large traumatic TMPs. However, the occurrence of otorrhea was significantly more common in patients treated with the Steri-Strips technique.

Abnormality of cervical vestibular-evoked myogenic potentials and ocular vestibular-evoked myogenic potentials in patients with recurrent benign paroxysmal postitional vertigo.

Abstract Conclusion: Our results show that cervical vestibular-evoked myogenic potential (cVEMP) or ocular VEMP (oVEMP) abnormalities in the recurrent benign paroxysmal positional vertigo (BPPV) group were significantly higher than those in the non-recurrent BPPV group. Therefore, we can infer that VEMP abnormality is one of risk factors for BPPV recurrence. Objective: This prospective study aimed to test the hypothesis that otolith dysfunction using the VEMP test is a cause of recurrence of BPPV. Methods: cVEMP and oVEMP tests using 500 Hz tone-burst stimuli were performed on 16 patients with recurrent BPPV between March 2010 and December 2011. Both VEMP tests were performed in 20 patients with non-recurrent BPPV. Results: The differences in age, sex, and involved canal between the recurrent and non-recurrent BPPV groups were not significant. Abnormal cVEMP responses were detected in 5 of 16 (31.3%) subjects in the recurrent BPPV group and abnormal oVMEP responses were detected in 4 of 16 (25%) subjects in the recurrent BPPV group. When we defined VEMP abnormality as an abnormal cVEMP or abnormal oVEMP, VEMP abnormalities were detected in eight (50%) subjects in the recurrent BPPV group and in three (15%) subjects in the non-recurrent BPPV group; the difference between groups was significant.

Simultaneous versus Subsequent Intratympanic Dexamethasone for Idiopathic Sudden Sensorineural Hearing Loss

Objective. The authors compared the efficacy of simultaneous and subsequent intratympanic dexamethasone injections for the treatment of idiopathic sudden sensorineural hearing loss. Study Design. Prospective randomized controlled multicenter study. Setting. Three tertiary university hospitals. Subjects and Methods. In the simultaneous intratympanic dexamethasone group, intratympanic dexamethasone was given initially with systemic steroids. In the subsequent intratympanic dexamethasone group, intratympanic dexamethasone was given 7 days after systemic treatment. The authors compared hearing outcomes between the groups according to Siegel’s criteria and frequency (0.25, 0.5, 1, 2, 3, 4, 6, and 8 kHz). Results. A total of 88 patients were analyzed in this study. There was no difference between the groups in hearing recovery according to Siegel’s criteria or frequencies. Neither recovery time nor early recovery differed between the groups. In the subsequent intratympanic dexamethasone group, 15 patients showed hearing recovery within 7 days and did not need intratympanic dexamethasone treatment. After intratympanic dexamethasone treatment, >28% (25/88) of the patients complained of otalgia, transient dizziness, ear fullness, and headache. Five percent of the patients showed small, transient perforations and otorrhea during intratympanic dexamethasone treatment. Conclusions. Simultaneous intratympanic dexamethasone did not confer an additional hearing gain or earlier recovery rate compared with subsequent intratympanic dexamethasone. A considerable number of patients did not need intratympanic dexamethasone for idiopathic sudden sensorineural hearing loss, and some patients experienced unnecessary side effects due to intratympanic dexamethasone. Therefore, the use of intratympanic dexamethasone is recommended only for subsequent or salvage treatment of idiopathic sudden sensorineural hearing loss after systemic steroid treatment.

Prevalence and risk factors of chronic otitis media: the Korean National Health and Nutrition Examination Survey 2010-2012.

Background The performance of nationwide studies of chronic otitis media (COM) in adults has been insufficient in Korea. We evaluated the prevalence and risk factors of COM in Korea. Methods This study was conducted using data from the fifth Korean National Health and Nutrition Examination Survey (n = 23,621). After excluding the subjects under 20 year old and suffered from cancers, 16,063 patients were evaluated for COM. Participants underwent a medical interview, physical examination, endoscopic examination, and blood and urine test. COM was diagnosed by trained residents in the Department of Otorhinolaryngology using an ear, nose, and throat questionnaire and otoendoscopy findings. Data on the presence and absence of COM were collected. Multivariate logistic regression analyses were performed to identify its risk factors. Results Of the 16,063 participants aged above 20 year old, the weighted prevalence of COM was 3.8%. In the multivariate analyses, the following factors showed high odds ratios (ORs) for COM: pulmonary tuberculosis (adjusted OR, 1.78; 95% confidence interval [CI], 1.06-3.01), chronic rhinosinusitis (adjusted OR, 1.87; 95% CI, 1.17-2.98), mild hearing impairment (adjusted OR, 1.95; 95% CI, 1.34-2.85), moderate hearing impairment (adjusted OR, 4.00; 95% CI, 2.21-7.22), tinnitus (adjusted OR, 1.82; 95% CI, 1.34-2.49), increased hearing thresholds in pure tone audiometry in the right ear (adjusted OR, 1.02; 95% CI, 1.01-1.03), and left ear (adjusted OR, 1.03; 95% CI, 1.02-1.04). The following factors showed low odds ratios for COM: hepatitis B (adjusted OR, 0.28; 95% CI, 0.08-0.94) and rhinitis (adjusted OR, 0.60; 95% CI, 0.42-0.88). In addition, high levels of vitamin D, lead, and cadmium, EQ-5D index; and low red blood cell counts were associated with development of COM (Student’s t-test, P < 0.01). Conclusions Our population-based study showed that COM is not rare in Korea, and its development may be associated with various host and environmental factors. Further research on its relationships and the pathogenesis are needed.

Protective effects of caffeic acid phenethyl ester (CAPE) against neomycin-induced hair cell damage in zebrafish

OBJECTIVEnCaffeic acid phenethyl ester (CAPE) is known to reduce the generation of oxygen-derived free radicals, which is a major mechanism of aminoglycoside-induced ototoxicity. The objective of the present study was to evaluate the effects of CAPE on neomycin-induced ototoxicity in zebrafish (Brn3c: EGFP).nnnMETHODSnFive-day post-fertilization zebrafish larvae (n=10) were exposed to 125 μM neomycin and one of the following CAPE concentrations for 1h: 50, 100, 250, 500, or 1000 μM. Ultrastructural changes were evaluated using scanning electron microscopy (SEM). The terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) assay and 2-[4-(dimethylamino)styryl]-N-ethylpyridiniumiodide (DASPEI) assay were performed for evaluation of apoptosis and mitochondrial damage.nnnRESULTSnCAPE decreased neomycin-induced hair cell loss in the neuromasts (500 μM CAPE: 12.7 ± 1.1 cells, 125 μM neomycin only: 6.3 ± 1.1 cells; n = 10, P < 0.05). In the ultrastructural analysis, structures of mitochondria and hair cells were preserved when exposed to 125 μM neomycin and 500 μM CAPE. CAPE decreased apoptosis and mitochondrial damage.nnnCONCLUSIONnIn the present study, CAPE attenuated neomycin-induced hair cell damage in zebrafish. The results of the current study suggest that neomycin induces apoptosis, and the apoptotic cell death can be prevented by treatment with CAPE in zebrafish.

Predictive and Prognostic Biomarkers of Respiratory Diseases due to Particulate Matter Exposure

Air pollution is getting severe and concerns about its toxicity effects on airway and lung disease are also increasing. Particulate matter (PM) is major component of air pollutant. It causes respiratory diseases, such as asthma, chronic obstructive pulmonary disease, lung cancer, and so on. PM particles enter the airway and lung by inhalation, causing damages to them. Especially, PM2.5 can penetrate into the alveolus and pass to the systemic circulation. It can affect the cardiopulmonary system and cause cardiopulmonary disorders. In this review, we focused on PM-inducing toxicity mechanisms in the framework of oxidative stress, inflammation, and epigenetic changes. We also reviewed its correlation with respiratory diseases. In addition, we reviewed biomarkers related to PM-induced respiratory diseases. These biomarkers might be used for disease prediction and early diagnosis. With recent trend of using genomic analysis tools in the field of toxicogenomics, respiratory disease biomarkers associated with PM will be continuously investigated. Effective biomarkers derived from earlier studies and further studies might be utilized to reduce respiratory diseases.

Effect of TiO2 Nanoparticles on Inflammasome-Mediated Airway Inflammation and Responsiveness

Purpose Nanoparticles (NPs) may cause cell and tissue damage, leading to local and systemic inflammatory responses and adverse effects on health due to the inhalation of particulate matter. The inflammasome is a major regulator of inflammation through its activation of pro-caspase-1, which cleaves pro-interleukin-1β (pro-IL-1β) into its mature form and may induce acute and chronic immune responses to NPs. However, little is known about the response of the inflammasome to NP exposure via the airways in asthma. The aim of this study was to identify the impact of titanium dioxide (TiO2) NPs on inflammasome in a mouse model of allergic asthma. Methods Mice were treated with ovalbumin (OVA) or TiO2 NPs. IL-1β, IL-18, NAIP, CIITA, HET-E, TP-2 (NACHT), leucine-rich repeat (LRR), pyrin domain-containing protein 3 (NLRP3), and caspase-1 were assessed by Western blotting. Caspase-1 was assessed by immunohistochemistry (IHC). Levels of reactive oxygen species (ROS)—as markers of oxidative damage—and the mediators 8-isoprostane and carbonyl were measured by enzyme-linked immunosorbent assay (ELISA). Results Airway hyperresponsiveness (AHR) and inflammation were increased in OVA-sensitized/challenged mice, and these responses were exacerbated by exposure to TiO2 NPs. NP treatment increased IL-1β and IL-18 expression in OVA-sensitized/challenged mice. NPs augmented the expression of NLRP3 and caspase-1, leading to production of active caspase-1 in the lung. Caspase-1 expression was increased and exacerbated by TiO2 NP exposure in OVA-sensitized/challenged mice. ROS levels tended to be increased in OVA-sensitized/challenged and OVA-sensitized/challenged-plus-TiO2 NP-exposed mice. Conclusions Our data demonstrated that inflammasome activation occured in asthmatic lungs following NP exposure, suggesting that targeting the inflammasome may assist in controling NP-induced airway inflammation and hyperresponsiveness.

Does the kyphotic change decrease the risk of fall

Objectives Falls are a major problem in the elderly. Age-related degeneration of the human balance system increases the risk of falls. Kyphosis is a common condition of curvature of the upper spine in the elderly and its development occurs through degenerative change. However, relatively little is known about the effect of kyphotic changes on balance in the elderly. The aim of this study is to investigate the influence of kyphosis on the balance strategy through use of the motor control test (MCT) in computerized dynamic posturography. Methods Fifty healthy subjects who were not affected by other medical disorders that could affect gait or balance were enrolled in the study. By simulation of kyphotic condition through change of the angles of the line connecting the shoulder to the hip and the ankle axis by approximately 30°, the latency and amplitude of the MCT were measured in upright and kyphotic condition. Results In the kyphotic condition, latency was shortened in backward movement. In forward movement, latency was shortened only in large stimulation. The amplitude in forward movement was decreased in kyphotic condition. However, the change of amplitude was not significant in large intensity backward movement in the same condition. Conclusion Kyphotic condition decreases the latency of MCT, especially in backward movement. These findings imply that kyphotic condition may serve as a protective factor against falls.

Middle ear inflammation of rat induced by urban particles.

OBJECTIVEnThe aim of this study was to evaluate the histologic change of middle ear mucosa and the expression levels of epithelial sodium channel (ENaC) subunits and mucin production genes, after the injection of urban particulate matter (UPM) into the middle ear cavity of rats.nnnMETHODSnFifty pathogen-free, male Sprague Dawley rats were assigned to the study. Transtympanic injection of UPM solution (300μg/ml, 50μl) was made into the middle ear cavity of rats. Rats were sacrificed at day 1 (group1); day 3 (group2); day 5 (group3); and day 14 (group4) after the procedure. The expression levels of ENaC subunits (α, β and γ) and mucin producing genes (MUC5AC and MUC5B) were analyzed using semi-quantitative real-time reverse transcriptase-polymerase chain reaction. Thickness of middle ear mucosa was measured and analyzed.nnnRESULTnAfter transtympanic injection, the thickness of middle ear mucosa increased significantly on day 1, 3 and 5 (p<0.05) and was normalized on day 14, compared to the control group. Inflammatory changes observed in the middle ear mucosa were subepithelial widening, inflammatory cell infiltration and vascular space widening on day 1, 3 and 5. These changes had reverted to normal on day 14. The level of ENaC-α expression decreased 0.60 fold on day 1 (p<0.05), but was normalized thereafter. The level of ENaC-β and γ decreased 0.39 and 0.27 fold, respectively, on day 1, was normalized on days 3 and 5, and increased 2.30 and 2.47 fold on day 14, respectively (p<0.05). The level of MUC5AC expression increased 1.97-fold on day 1 (p<0.05) and 2.58-fold on day 5 (p<0.05), but was normalized on day 14. The level of MUC5B expression increased 5.4-fold on day 1, 3.14-fold on day 3, 3.85-fold on day 5, and 2.46-fold on day 14, respectively (p<0.05).nnnCONCLUSIONnTranstympanic injection of UPM solution into the middle ear cavity of rat induced a characteristic inflammatory response and altered gene expression related with inflammation and mucin production. These findings provide a useful clue for the understanding of how air pollutants, particularly UPM, contribute to the development of otitis media.

Effect of cadmium on human middle ear epithelial cells

OBJECTIVEnCadmium (Cd(2+)) exposure can occur through passive smoking, ambient air pollution, and food. Even low exposure can affect hearing and cause lung disease. Here we investigated whether cadmium causes cytotoxicity, induces inflammation, or increases mucin gene expression in immortalized human middle ear epithelial cells (HMEECs).nnnMATERIALS AND METHODSnCell viability was investigated using the MTT assay following Cd(2+) treatment. Increases in apoptosis and necrosis were determined, and the production of reactive oxygen species (ROS) was measured. We analyzed the expression of an inflammatory cytokine (COX-2) gene and a mucin gene (MUC5AC) using RT-PCR.nnnRESULTSnExposure to >20 µM Cd(2+) caused a significant decrease in cell viability. Hoechst 33258 staining showed apoptotic morphology of heterogeneous intensity, condensation, and fragmentation after Cd(2+) exposure. Cd(2+) was shown to increase cell death by apoptosis and necrosis by annexin V-FITC/PI double staining. Cd(2+) exposure increased ROS production and COX-2 and MUC5AC expressions.nnnCONCLUSIONnOur findings suggest that environmental cadmium exposure is related to the development of otitis media.