Tae-Bin Won

Changes of Nasal Function After Temperature-Controlled Radiofrequency Tissue Volume Reduction for the Turbinate

Objectives Temperature‐controlled and temper‐ature‐monitored radiofrequency tissue volume reduction (RFTVR) for the turbinate is a new treatment modality for nasal obstruction secondary to turbinate hypertrophy. We compared the nasal functions after the treatment of RFTVR and laser vaporizing turbinoplasty (LVT) using subjective symptom scores and objective tests.

Treatment modalities and outcomes of olfactory neuroblastoma

To analyze the clinical features of olfactory neuroblastoma (ONB) and compare the treatment results according to various treatment modalities, and to validate various staging systems.

Induction of airway remodeling of nasal mucosa by repetitive allergen challenge in a murine model of allergic rhinitis

BACKGROUNDnAlthough many studies regarding airway remodeling in asthma have been reported, only a few studies have investigated airway remodeling in allergic rhinitis.nnnOBJECTIVESnTo determine whether repetitive allergen challenge could induce airway remodeling in the nose and evaluate the effect of steroids using a murine model of allergic rhinitis.nnnMETHODSnTo develop a mouse model of airway remodeling, ovalbumin-sensitized mice were repeatedly exposed to inhaled ovalbumin administration twice a week for 1 month and 3 months. Matched control mice were challenged with phosphate-buffered saline, and the treatment group received intraperitoneal dexamethasone injection. Trichrome, periodic acid-Schiff, hematoxylin-eosin, and immunohistochemical staining against matrix metalloproteinase 9 and tissue inhibitors of metalloproteinase 1 were performed to nasal and lung tissues, and the level of transforming growth factor beta in the nasal lavage fluid was analyzed.nnnRESULTSnRepetitive ovalbumin challenge for 3 months induced circumferential peribronchial fibrosis in the lung. In the nose, subepithelial fibrosis, increased matrix metalloproteinase 9 and tissue inhibitors of metalloproteinase 1 expression, goblet cell hyperplasia, and submucous gland hypertrophy were observed compared with the control group. Features of airway remodeling were more prominent in the lung tissue. Administration of dexamethasone significantly inhibited these histologic changes.nnnCONCLUSIONnAirway remodeling associated with long-term allergen challenge can occur in the nasal mucosa and the lung. Steroid treatment prevents airway inflammation in response to acute allergen challenge, as well as airway remodeling by long-term allergen challenge.

Effects of staphylococcal enterotoxin on ciliary activity and histology of the sinus mucosa

Conclusion. The results of our study suggest that Staphylococcus aureus enterotoxin A (SEA) may play an important role in the pathogenesis of rhinosinusitis by ciliostatic effects at high concentrations, and by a different mechanism at low concentrations. Objectives. To investigate the in vitro effects of SEA on ciliary activity and its in vivo effects on histology of the sinus mucosa. Materials and methods. The in vitro effects of SEA on ciliary activity at different concentrations and exposure time were investigated using maxillary sinus mucosa harvested from experimental rabbits. After in vivo instillation of different concentrations (high and low dose) of SEA into the maxillary sinus, ciliary beat frequency (CBF) and histologic findings of the maxillary sinus mucosa were examined. Results. After exposure to low doses of SEA (0.03 and 0.3 ng/ml), CBF did not decrease, but after exposure to high doses of SEA (1.5, 3, and 30 ng/ml), CBF decreased significantly as a function of time. At 24 h after instillation of high-dose SEA (30 ng/ml) into the sinus, CBF decreased significantly and rhinosinusitis was induced after 7 days. Although no alteration was observed in the CBF of the sinus mucosa after instillation of low-dose SEA (0.3 ng/ml), histological findings of rhinosinusitis including subepithelial edema and inflammatory cell infiltration were observed.

Histamine Induces MUC5AC Expression via a hCLCA1 Pathway

Background: Histamine is an important inflammatory mediator and associated with early phase allergic response. However, the involvement of histamine in mucin gene expression or production has not been elucidated. Objective: The aim of this study is to investigate whether histamine induces MUC5AC production in NCI-H292 cells, and to evaluate which pathway is involved in this mucin production. Methods: MUC5AC production in NCI-H292 cells was analyzed by RT-PCR, immunoassay and immunocytochemical analysis. The effect of histamine on MUC5AC production in these cells at different time courses and concentrations was assessed, and the relationship between hCLCA1 expression and histamine concentration was also evaluated. In addition, cells were pretreated with antihistamine or an hCLCA1 blocker (niflumic acid, NFA) to evaluate the mechanism underlying histamine-induced MUC5AC production. Results: Histamine upregulated MUC5AC gene expression and mucin protein production in a dose-dependent and time-related fashion. Histamine also dose-dependently increased hCLCA1 mRNA expression. Moreover, pretreatment of cells with chlorpheniramine or NFA reduced histamine-induced MUC5AC mRNA expression and protein production in these cells. The histamine-treated cells showed increased cytoplasmic staining for MUC5AC compared to cells treated with media alone, and cells pretreated with chlorpheniramine or NFA before histamine treatment. Conclusion: Our results suggest that histamine-induced MUC5AC production occurs via the upregulation of hCLCA1. It is assumed that antihistamines or hCLCA1 channel blockers can partially suppress histamine-induced MUC5AC production in allergic diseases, e.g. allergic rhinitis.

Effects of Dexamethasone on the Expression of Transforming Growth Factor-β in the Mouse Model of Allergic Rhinitis

Objectives/Hypothesis: This study aimed to evaluate the effect of dexamethasone on the expression of transforming growth factor (TGF)‐β in the mouse model of allergic rhinitis.

Acoustic characteristics of snoring according to obstruction site determined by sleep videofluoroscopy

Abstract Conclusion: Acoustic characteristics of snoring sound, such as pitch and formant, differed according to the site of upper airway obstruction determined by sleep videofluoroscopy (SVF). Snoring sound analysis can complement determination of the site of obstruction in snoring and sleep apnea patients. Objectives: The aim of this study was to evaluate the acoustic characteristics of snoring according to obstruction site determined by SVF. Methods: Ninety patients who underwent simultaneous snoring sound recording during SVF were included in this study. Acoustic parameters of snoring such as pitch (min, mean, max) and formant (1,2) were analyzed. Site of obstruction was determined by SVF and classified according to anatomic structure and level of obstruction. Results: Mean value of peak frequency showed significant difference between soft palate and isolated tongue base or epiglottis obstruction and combined obstruction involving soft palate and tongue base or epiglottis. Peak frequency of velopharyngeal obstruction showed difference only with hypopharyngeal obstruction. First formant showed similar results in the structure classification whereas velopharyngeal obstruction showed significant difference compared with other levels of obstruction. Other parameters (intensity, jitter, shimmer) did not show significance according to site of obstruction.

Functional recovery of rabbit maxillary sinus mucosa in two different experimental injury models.

Objective/Hypothesis: Ciliary wave disorder (CWD) is essential for effective mucociliary transport. The purpose of this study was to investigate morphologic and functional restoration in recovered sinus mucosa after 12 weeks of experimentally induced rhinosinusitis and regenerated sinus mucosa after mechanical injury.

Duox2 is required for the transcription of pattern recognition receptors in acute viral lung infection: An interferon-independent regulatory mechanism.

The innate immune response, which constitutes the first line of defense against influenza A virus (IAV) infection, is activated by pattern recognition receptors (PRRs) that recognize viral structures. We found that the PRRs, retinoic acid-inducible gene 1 (RIG-I) and melanoma differentiation-associated protein 5 (MDA5), which have been implicated as interferon (IFN)-stimulated genes, were dominantly responsible for the recognition of IAV in lungs of mice at 3 and 7 days post infection (dpi). Intranasal administration of IFNs enhanced RIG-I and MDA5 gene expression after IAV infection and mRNA levels of RIG-I and MDA5 were significantly reduced at 7 dpi in mice with neutralization of secreted IFNs. However, blockade of IFNs did not alter the transcription of RIG-I and MDA5 at 3 dpi. We studied the antiviral effect of Duox2 inxa0vivo lung to elucidate the role of Duox2 in respiratory mucosa. RIG-I and MDA5 mRNA levels were induced to a lower extent in lungs of mice that were inoculated with Duox2 small hairpin RNA regardless of secreted IFNs at 3 dpi. We propose that Duox2 is responsible for IFN-independent signaling for induction of PRRs transcription and can control acute IAV lung infection at the beginning of infection.

Intranasal delivery of Duox2 DNA using cationic polymer can prevent acute influenza A viral infection in vivo lung

We studied the contribution of Duox2 in mucosal host defense against influenza A virus (IAV) infection in in vivo lung. We found that Duox2 was required for the induction of type I and III interferon (IFN)s and transient Duox2 overexpression using cationic polymer polyethyleneimine (PEI) leads to suppression of IAV infection in in vivo lung. Twenty mice (C57BL/6J) were anesthetized and challenged by intranasal administration of 213xa0pfu/30xa0μl of IAV (WS/33/H1N1), and IAV-infected mice were euthanized at 1, 3, 5, 7, 10, 14xa0days post infection (dpi). Duox2 small hairpin RNA (shRNA) and pCMV-Duox2 formulated with PEI were inoculated to mice to assess the regulatory mechanism between Duox2 and IFN secretion. Following intranasal IAV inoculation, viral infection was significantly aggravated from 3xa0dpi in in vivo lung and viral titer was highest at 7xa0dpi. Consistent with this, Duox2 messenger RNA (mRNA) and protein expressions were significantly induced from 3xa0dpi in the lung tissue of IAV-infected mice. Viral titer was much higher in IAV-infected mice that were inoculated with Duox2 shRNA accompanied with lower survival rate and extensive lung pathologies. Interestingly, severe lung pathologies in IAV-infected mice were not observed and viral titer was significantly reduced in mice with pulmonary administration of pCMV-Duox2 formulated with PEI before IAV inoculation. Both mRNA and secreted protein levels of IFN-β and IFN-λ2/3 were highly elevated in IAV-infected mice with pCMV-Duox2 formulated with PEI. Duox2 is necessary for the regulation of IFN secretion in in vivo lung, and pulmonary administration of Duox2 DNA using cationic polymer triggers the induction of type I and III IFNs resulting in more complete suppression of IAV infection.