Effects of Ebselen on Ozone-Induced Nasal Mucosal Inflammation in Mice / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Although the mechanism of ozone-induced airway inflammation and hyperresponsiveness is largely unknown, NO and peroxynitrite has been suggested to be associated with it. Ebselen, a seleno-organic compound, is known to inhibit the production of superoxide, iNOS-related NO, and their combined product, peroxynitrite. The purpose of this study is to investigate whether ebselen suppress ozone-induced nasal inflammation and whether ebselen inhibit the production of NO and peroxynitrite in nasal mucosa. SUBJECTS AND METHOD: Thirty-six BALB/c mice were divided into three groups: control group, ozone exposure group, and ozone+ebselen treated group. In the ozone exposure group, mice were exposed to 1 ppm ozone for 8 hours a day for 3 consecutive days. In the ebselen treated group, the ebselen (32.5 mg/kg) solution was injected intraperitoneally 1 hour before and 3 hours after the ozone exposure. At 18 hours of the last ozone exposure, Evans blue was infused via tail vein in 6 animals of each group. Mice were sacrificed five minutes later and nasal mucosa was obtained to measure the amount of extravasated Evans blue dye. From the remaining 6 animals in each group, nasal lavage fluid (NLF) was obtained to measure the concentration of albumin and the number of neutrophils. After lavage fluid was obtained, nasal mucosa was taken for immunohistochemical staining against iNOS and nitrotyrosine usng the ABC method. RESULTS: Extravasation of Evans blue was significantly increased in the ozone exposure group, but it was significantly decreased in the ebselen treated group. Albumin concentration in NLF showed a tendency to increase in the ozone exposure group and a tendency to decrease in the ebselen treated group when compared with the ozone exposure group. The number of neutrophils was significantly increased in the ozone exposure group and was decreased more in the ebselen treated group than in the ozone exposure group. Immunoreactivity to iNOS and nitrotyrosine was strongly expressed in nasal mucosa of the ozone exposure group. However, it was nearly abolished by the treatment with ebselen. CONCLUSIONS: These results may suggest that ebselen can be applied as a useful therapeutic agent for airway diseases by modulating the oxidant-related inflammatory process.

Inverted Papilloma of the Nose and Paranasal Sinuses: An Analysis of 102 Cases / 대한이비인후과학회지

OBJECTIVES: Inverted papilloma is characterized by a high rate of recurrence, local aggressiveness and association with malignancy. We reviewed the 16-year experience of our institution in clinical presentation, history and the recurrence rate according to the tumor stage and surgical modalities. MATERIALS AND METHOD: A retrospective study was conducted on 102 patients diagnosed as inverted papilloma between January, 1986 through August, 2002. Demographic data, clinical presentations, and association with malignancy were analyzed. All patients with inverted papilloma were staged according to the Krouse's staging system. Sixty eight patients followed up at least 6 months were divided into endoscopic and conventional surgery groups. We compared the recurrence rate between the two groups according to the tumor stage. RESULT AND CONCLUSION: Patients were aged 19 to 81 years, and 73.5% were male. The most frequent presenting complaint was nasal obstruction. The most common site of involvement was the lateral nasal wall in the region of the middle meatus. The overall malignancy rate was 8.8% (9 cases), with synchronous tumors accounting for 7 cases and metachronous tumors accounting for 2 cases. When patients were first diagnosed, the most common stage was T2 (52.7%). The recurrence rates of T1, T2 and T3 were 10%, 11.1% and 4.8%, respectively, with no significant difference. Also the recurrence rates in endoscopic and conventional surgery group according to the stage had no significant difference.

Effect of Saponin, Allopurinol and Nimodipine on Noise Induced Treshold Changes of ABRs in Guinea Pigs / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Several studies have demonstrated that noise exposure may result in cochlear damage. The purpose of this study was to evaluate the effect of red Korean ginseng saponin (Krg-saponin), allopurinol and nimodipine on the auditory brainstem response (ABR) threshold changes after noise exposure. MATERIALS AND METHOD: Twenty-two healthy guinea pigs (44 ears) were divided into 4 groups; control, Krg-saponin (100 mg/kg, intraperitoneal), allopurinol (50 mg/kg, intraperitoneal) and nimodipine (2 mg/kg, subcutaneous) treated groups. Guinea pigs were exposed to 115 dB, 1500 Hz narrow band noise for 12 hours. ABR threshold shifts were observed for 24 hours after the noise exposure. RESULTS: Threshold shift after noise exposure was significantly reduced in Krg-saponin, allopurinol and nimodipine-treated groups, and allopurinol showed significantly greater effect on reducing threshold shift than nimodipine. Krg-saponin was less effective than allopurinol but more effective than nimodipine on reducing the threshold shift after noise exposure. CONCLUSION: The result suggests that the drug could block the formation of free oxygen radicals (FORs) and that scavenge FORs can be most effectively used to attenuate the noise-induced cochlear damage.