The Effect of All-Trans Retinoic Acid on Culture of Aural Cholesteatoma Keratinocytes / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Retinoids have recently become an interest to clinicians because of their ability to inhibit migration and proliferation of the premalignant squamous cells, while enhancing growth and proliferation of normal cells. Aural cholesteatoma is defined as the state of hyperproliferative keratinocytes in the middle ear cavity. An in vitro investigation was undertaken to determine whether all-trans retinoic acid (t-RA) exhibits an inhibitory effect on cholesteatoma cell proliferation. METHODS: Cholesteatoma tissue was obtained during a middle ear operation, and the explant was cultured on six well-plates in a culture medium of Medium M-154 (Cascade Biologics Inc., USA) for one week. T-RA was then treated with 10M, 10M, 10M, 10M concentrations, respectively. The cholesteatoma explant cultures were observed daily, and topographic maps were constructed weekly to quantify the proliferation area. The explant culture area was estimated by Multiscan. RESULTS: In the absence of t-RA, the cholesteatoma explant culture area reached 401.5mm in four weeks. But with the administration of t-RA, the cultured area decreased proportionally to t-RA concentrations which reduced to 224.0 mm, 94.4 mm respectively in four weeks with 10M, 10M concentration of t-RA (p<0.05). CONCLUSIONS: This investigation showed that t-RA has a significant inhibitory effect on cholesteatoma proliferation. These results suggest that retionoids may have a role in controlling cholesteatoma disease.

The Prevalence of Otitis Media with Effusion among Kindergarten and Elementary School Children in Song Buk, Seoul, Korea and Risk Factors / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Otitis media with effusion (OME) is the most common bacterial infection and the most frequent otologic indication for antimicrobial or surgical therapy in young children. It is also the leading cause of hearing disturbance in children. There have been few reports about the prevalence rate of OME in preschool children in Seoul. So, we investigated the prevalence of OME among kindergarten and elementary children in Song Buk Gu, Seoul, Korea. MATERIAL AND METHODS: Tympanometry and pneumatic otoscopic examination were performed on 3,364 children aged 3-7 years, from March to June of 1999. RESULTS: A total of 11.74% of the subjects had unilateral or bilateral OME. The prevalence rate of OME in 3 year-old children was 30.0% and that of 7 year-old children was decreased to 8.9%. The prevalence rate in March was 18.5% and that in June decreased to 6.5%. The majority of the cases were free of subjective symptoms, but some of significant symptoms were ear fullness, otalgia, tendency to increase the TV volume and autophonia. CONCLUSION: Significant risk factors are seasonal variation, age and the history of OME. There should be more attention paid to OME in children aged 7 years and younger, because its high prevalence and less symptoms.

Allergic Rhinitis to Japanese Cedar in Cheju Island / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Abundance of Japanese cedars (JC) in Cheju Island has caused some of the island's residents to suffer from severe allergic symptom in the spring time. This study was carried out to verify the presence of JC allergic rhinitis (AR) in the island. Materials and Method: We performed a history survey, skin testing and nasal provocation test to JC and other common allergens for 170 residents who have symptom of AR. We also performed the same tests in 18 Japanese who had history of AR to JC and have lived in Korea more than 3 years. And as a control, skin tests were performed for 581 patients who live in Seoul. RESULTS: Positive reactions to JC were seen in 22.4% of the resident group. The prevalence rate was remarkable in the state capital of Cheju. These reactions were associated with conjunctivitis, dermatitis, asthma and food allergy. All the 18 Japanese patients were sensitive to JC. However, the allergic symptoms disappeared within 1 year after the move to Korea. And there were no patients sensitive to JC in the control subjects. Conclusions: We confirmed the presence of AR of JC in Cheju island. The distribution is comparatively coincided with JC and/or air pollution and this result indicate that environmental factors can be involved in the manifestation of the disease.