When exposed to different types of bacteria in the oral cavity, denture based resins are prone to bacteria attachment. The purpose of this study was to investigate the physical, biological, and antimicrobial properties of denture base resins coated with Peony extract (200, 400, and 600 μg/mL). Specifically, the surface properties (microhardness, contact angle, and color change of the coated specimens), cell cytotoxicity (measured using MTT assay), and antimicrobial activity (against S. mutans (Streptococcus mutans) and C. albicans (Candida albicans) using a growth inhibition assay) were evaluated. The polyphenol content was measured using ultraviolet-visible (UV-vis) spectrometry. The experimental groups (specimens coated with Peony extract) and a control group (specimens coated without Peony extract) were statistically compared using a one-way analysis of variance and Tukey’s post-hoc tests. No statistically significant differences in surface properties or cell cytotoxicity were observed, which demonstrated their biocompatibility. Conversely, a statistically significant difference in antimicrobial activity was observed between the experimental and control groups after 48 h. This confirms the antimicrobial activity of the denture base resin coated with Peony extract and demonstrates that it is a promising dental material for preventing stomatitis.

본 연구의 목적은 국제기업가정신의 속성을 글로벌 차원에서 도출하고 국제화 기회를 유형화하여, 국제기업가 정신과 기회의 적합성을 제안하기 위한 것이다. 따라서 첫째, SSCI급 경영 전문 국제학술지 일곱 종에 2000~2015 년 사이에 게재된 연구 논문을 탐색하고, 기업가의 국제경영 활동을 반영하여 국제기업가정신의 8개 속성을 도출 하였다. 둘째, 국제화 동기를 주제어로 하는 연구를 분석하여 자원을 탐색하거나 활용하는 경제 행위에 따라 4개의 국제화 기회 유형으로 분류하고 그 특성을 정의하였다. 셋째, 이를 바탕으로 개념적 모델을 개발하여 국제기업가 정신과 기회의 적합성을 밝히고 국제기업가정신, 국제화 기회, 그리고 국제화 성과와의 영향 관계에 대해 명제를 제시하였다. 이상의 분석을 통해, 국제화 기회가 발생했을 때 이를 인지하고 분석․대응하기 위하여 어떠한 국제 기업가정신이 필요한지 적합성이 밝혀진다면 기업의 국제화 성과에 이론적․실무적 시사점을 줄 것으로 기대한다.

The aim of this study was to enhance the proliferation efficiency of spermatogonial stem cells (SSCs). In order to improve the proliferation efficiency, we investigated new factors that promote the proliferation of SSCs using in vitro culture method with natural plant extracts. Germ cell populations containing SSCs were collected 6- to 8-days-old from C57BL/6-TG-EGFP (C57GFP) mice and SSCs were isolated from the collected cells via magnetic-activated cell sorting (MACS). Since then, SSCs were cultured for a week with culture medium containing natural plant extracts at concentration of 0.1, 1, and 10 μg/mL. After a week of culture, we looked for an increase, especially a dose-dependent increase, in the number of cells compared to that of the control group. A dose-dependent increase, in the number of cells was observed in the Petasides japonicus-treated groups. Furthermore, we carried out repeated experiment that is process consisting of selection and additional segmentation to explore new factors for activating SSCs at the molecular level. As a results, Petasides japonicus butanol fraction significantly increased the proliferation rate of SSCs in a dose-dependent manner among Petasides japonicus fraction samples. We identified normal expression level of PLZF in SSCs cultured with plant extracts using immunocytochemistry method. Furthermore, we also carried out qRT-PCR and identified normal expression level of Lhx1 and GFRα1. The finding of this study could contribute to improvement of proliferation and activation for SSCs, using culture method with natural plant extracts.