폴리비닐실록산 치과용 인상재의 제조시 나노필러를 이용한 물성증진 효과에 관한 연구

김민강,송호준,박영준 대한치과재료학회 2006 대한치과기재학회 학술대회 Vol.2006 No.5

생체유사용액에 BSA 혼합 방법이 골유사형 아파타이트의 형성과 특성에 미치는 영향

김민강,조준영,정상헌,박영준,송호준 대한치과재료학회 2010 대한치과기재학회 학술대회 Vol.2010 No.4

The Antioxidant Effect of Small Extracellular Vesicles Derived from Aloe vera Peels for Wound Healing

김민강,Choi Young Chan,Cho Seung Hee,Choi Ji Suk,조용우 한국조직공학과 재생의학회 2021 조직공학과 재생의학 Vol.18 No.4

Background: Extracellular vesicles (EVs) derived from plants have emerged as potential candidates for cosmetic and therapeutic applications. In this study, we isolated EVs from Aloe vera peels (A-EVs) and investigated the antioxidant and wound healing potential of A-EVs. Methods: A-EVs were isolated by ultracentrifugation and tangential flow filtration and were characterized using transmission electron microscopy, nanoparticle tracking analysis. The cytotoxicity and cellular uptake of A-EVs were investigated by WST-1 assay and flow cytometry. The antioxidant effect of A-EVs was evaluated by superoxide dismutase (SOD) activity assay and cellular antioxidant activity (CAA) assay. The wound healing potential was assessed by in vitro scratch assay using human keratinocytes (HaCaT) and fibroblasts (HDF). The expression of nuclear factor erythroid 2–related factor 2 (Nrf2) and their associated genes was analyzed by quantitative RT-PCR. Results: A-EVs displayed a round shape and had diameters from 50 to 200 nm. A-EVs showed good cytocompatibility on human skin cells and were internalized into HaCaT cells via clathrin-, caveolae-mediated endocytosis, and membrane fusion. The SOD activity and CAA assays exhibited that A-EVs had antioxidant activity and reduced intracellular ROS levels in H2O2-treated HaCaT cells in a dose-dependent manner. A scratch assay showed that A-EVs enhanced the migration ability of HaCaT and HDF. Moreover, A-EVs significantly upregulated the mRNA expression of Nrf2, HO-1, CAT, and SOD genes in H2O2-treated HaCaT cells. Our findings reveal that A-EVs could activate the antioxidant defense mechanisms and wound healing process via the Nrf2 activation. Conclusion: Overall results suggest that the A-EVs are promising as a potential agent for skin regeneration. Background: Extracellular vesicles (EVs) derived from plants have emerged as potential candidates for cosmetic and therapeutic applications. In this study, we isolated EVs from Aloe vera peels (A-EVs) and investigated the antioxidant and wound healing potential of A-EVs. Methods: A-EVs were isolated by ultracentrifugation and tangential flow filtration and were characterized using transmission electron microscopy, nanoparticle tracking analysis. The cytotoxicity and cellular uptake of A-EVs were investigated by WST-1 assay and flow cytometry. The antioxidant effect of A-EVs was evaluated by superoxide dismutase (SOD) activity assay and cellular antioxidant activity (CAA) assay. The wound healing potential was assessed by in vitro scratch assay using human keratinocytes (HaCaT) and fibroblasts (HDF). The expression of nuclear factor erythroid 2–related factor 2 (Nrf2) and their associated genes was analyzed by quantitative RT-PCR. Results: A-EVs displayed a round shape and had diameters from 50 to 200 nm. A-EVs showed good cytocompatibility on human skin cells and were internalized into HaCaT cells via clathrin-, caveolae-mediated endocytosis, and membrane fusion. The SOD activity and CAA assays exhibited that A-EVs had antioxidant activity and reduced intracellular ROS levels in H2O2-treated HaCaT cells in a dose-dependent manner. A scratch assay showed that A-EVs enhanced the migration ability of HaCaT and HDF. Moreover, A-EVs significantly upregulated the mRNA expression of Nrf2, HO-1, CAT, and SOD genes in H2O2-treated HaCaT cells. Our findings reveal that A-EVs could activate the antioxidant defense mechanisms and wound healing process via the Nrf2 activation. Conclusion: Overall results suggest that the A-EVs are promising as a potential agent for skin regeneration.

신자유주의적 인사혁신의 맥락에서 인사공정성과 조직시민행동

김민강,박통희 한국행정학회 2008 韓國行政學報 Vol.42 No.3

It is argued that the fairness of personnel administration is critical to the success of the new liberal personnel reforms by the Seoul Metropolitan Government, which are adopted to decrease the dysfunctions of the strong job security that is generally found in the Korean public sector. This paper empirically examines the direct and indirect effect of personnel fairness, job threats, and organizational trust on organizational citizenship behavior. Different from the social argument that low personnel fairness exacerbates the perception of job threats and destructs organizational citizenship behaviors, the study cannot find that personnel administrative fairness weakens job threat perception. Unexpectedly, the distributive fairness of personnel administration decreases organizational citizenship behavior contrary to theoretical prediction. Further, job threats increase organizational citizenship behavior differently from social concerns in that it destructs the informal behavior. However, similar to the existing studies, the interactional fairness of personnel administration promotes organizational trust that promotes organizational citizenship behavior. 정부의 경쟁력은 공식적 역할행동과 함께 역할 외의 조직시민행동이 활성화됨으로써 증진될 수 있다. 신자유주의자들은 경쟁과 평가를 강화하는 인사혁신을 통해 공식적인 역할행동의 효율성 제고에 진력하 고 있다. 본 연구에서는 공직의 강력한 신분보장의 역효과를 타개하기 위한 최근의 신자유주의적 인사혁 신을 맥락으로 조직시민행동에 대한 인사공정성, 직위위협, 그리고 조직신뢰의 영향을 살펴보았다. 분석 결과 낮은 인사공정성이 직위위협을 심화시키며 조직시민행동을 파괴한다는 사회적 담론과는 달리, 인사 공정성은 직위위협에 통계적으로 유의미한 영향을 미치지 않았다. 더구나 분배공정성을 높게 인식하는 공무원들이 오히려 조직시민행동에 소극적인 것으로 나타났다. 또한 직위위협도 조직시민행동을 파괴할 것이라는 사회적 우려와는 달리 오히려 증진시키는 것으로 밝혀졌다. 그러나 조직에 대한 신뢰는 기존연 구와 마찬가지로 조직시민행동을 제고하는 것으로 확인되었다.

마이크로아크산화 처리된 티타늄 금속 상에 열수처리에 의하여 형성된 나노 결정의 특성 연구

김민강,송호준,정영화,문원진,박영준 대한치과재료학회 2010 대한치과기재학회 학술대회 Vol.2010 No.11

치과대학생이 지각하는 스트레스의 원인: 평가척도 개발

김민강,한수부 한국의학교육학회 2005 Korean journal of medical education Vol.17 No.3

Purpose: The purpose of this study was to investigate the perceived sources of stress among dental students. The relationships of these stresses to the year of study and gender were also examined. Methods: The responses from the first to fourth year dental students to 30 items adapted from Dental Environment Stress(DES) questionnaire were subjected to confirmatory factor analysis. The Likert scale, ranging from 0(not applicable) to 4(very stressful), was applied to these items. A total of 341 students(male=196, female=145) participated, their average age being 24.7. Multivariate analysis of variance(MANOVA) was conducted to analyze the effects of the year of study and gender on stressors. Results: Confirmatory factor analysis established a five-factor model including 1) clinical practice, 2) academic load and pressure, 3) personal problems, 4) low self-esteem, and 5) school administration or climate. Subscales for each factor show good internal consistency with Cronbach's alpha ranging from .71 to .88. Mean score for factor II(academic load and pressure) was the highest among all factors for all of 4 years, which meant that primary stressors were amount of classwork, shortage of time, and competition among classmates regardless of the year of study. MANOVA result showed that the amount of stress from clinical practice and school climate generally increased through the years(p<.01), and that female students were more stressed than male students(p<.01). Conclusion: Students' stress is related to the features of the curricula and the learning environment. In reducing this stress, it would be helpful to modify the curriculum as well as to introduce mentor or counselor programs.

의과대학과 의학전문대학원 학생들의 진로선택동기 및 도덕판단력 비교

김민강,강진오 한국의학교육학회 2007 Korean journal of medical education Vol.19 No.2

Purpose: This study was performed to investigate the differences in career choice motives and moral reasoning ability between students in baccalaureate and graduate-entry medical programs. Methods: Forty-five students from a baccalaureate program and thirty-eight students from a graduate-entry program participated in this study. The students were required to fill out both the Career Choice Motivation Inventory and Defining Issues Test(DIT). The Career Choice Motivation Inventory is a 20-item questionnaire, which investigates five dimensions: effect of others, job security, interest in science, service and working with people, and working condition. Independent t-test was performed to compare the two groups. Pearson correlation coefficients were calculated to investigate the relationship among variables. Results: There were significant differences in career choice motivations between the two groups. Students in the graduate-entry program were more likely to be motivated by scientific interest and opportunities to care for people. Status and job security were stronger factors in the baccalaureate students. For the students in this program, there were positive associations among their motives- interest in medical science, serving people, and working condition. There was no significant difference in moral reasoning ability between the two groups. Conclusion: Students in the graduate-entry medical program seem to have more professional and altruistic motivations for entering medicine. Although there is nostatistical significance, graduate students have numerically higher moral reasoning abilities compared to their counterparts. These results validate that a graduate-entry program provides an important alternative for student selection.

알레르기 ; 단일기관에서 전산을 통해 수집된 자발적 약물유해반응 보고사례들의 분석

김민강 ( Min Gang Kim ),강혜련 ( Hye Ryun Kang ),김주희 ( Joo Hee Kim ),주영수 ( Young Soo Ju ),박성훈 ( Sung Hoon Park ),황용일 ( Yong Il Hwang ),장승훈 ( Seung Hun Jang ),김동규 ( Dong Gyu Kim ),정기석 ( Ki Suck Jung ) 대한내과학회 2009 대한내과학회지 Vol.77 No.5

저자는 2007년 9월부터 2008년 10월까지 한림대 성심병원에서 보고된 약물유해반응 사례들의 원인약물과 임상양상을 분석하였다. 전산화 시스템을 도입한 이래 보다 효율적으로 약물유해반응을 수집할 수 있었으며, 병동별 약물유해반응 담당자를 정함으로써 안정적인 약물감시체계를 정착시킬 수 있었다. 보고된 1,112건 중 인과성이 있다고 평가된 사례는 980건이었으며, 이 중 원인 약물로 의심되는 약제는 항생제, tramadol, 조영제, 아편계 진통제 순이었다. 보고사례들 나이가 많을수록 증상이 심한 사례의 비율이 높았으며, 성별에 따라서는 여자들의 평균 연령이 남자들보다 높았다. Tramadol, NSAIDs로 인한 약물 유해반응 보고사례에서는 여자가 차지하는 비율이 높았다. 가장 흔한 임상양상은 피부 발진과 두드러기 등의 피부 이상반응이었고, 오심, 구토 등의 소화기계반응이 그 뒤를 이었다. Background/Aims: The recent introduction of computerized surveillance systems has promoted the monitoring of adverse drug reactions (ADRs), a feature that facilitates voluntary reports and enables prompt feedback. To investigate the causative agents and severity of ADRs that occurred in a single hospital, we analyzed the features of 980 ADRs that occurred over 14 months after developing a computerized ADR reporting system in Hallym Sacred Heart Hospital. Methods: ADR data collected prospectively from September 2007 to October 2008 by a computerized reporting system were analyzed. The World Health Organization-Uppsala Monitoring Center (WHO-UMC) criteria were used to determinate causality for each ADR. Results: The number of ADR cases reported voluntarily increased rapidly since the introduction of the computerized ADR reporting system. Of the 980 cases, antibiotics (34.5%) were the most common causative drugs, followed by analgesics such as tramadol and its compound (15.2%), radiocontrast media (7.0%), narcotics (5.9%), and nonsteroidal anti-inflammatory drugs (NSAIDs) (5.5%). Fifty-nine (6.0%) and 206 (21.0%) cases were classified as severe and moderate reactions, respectively. The mean age was older in patients with severe ADRs than in patients with non-severe ADRs. The most common clinical features were skin manifestations, such as pruritus, skin eruptions, and urticaria. Gastrointestinal symptoms including nausea, vomiting, and diarrhea were the second most frequently reported ADRs. Among antibiotics, first-generation cephalosporins were the most frequently reported causative drugs, followed by second-generation cephalosporins, penicillin/β-lactamase inhibitors, and third-generation cephalosporins. While 11.6% of ADRs related to penicillin/β-lactamase inhibitors were classified as severe, there was only one severe ADR (1.1%) for first-generation cephalosporins. Most ADRs were reported equally in men and women, although female cases constituted about two thirds of ADRs associated with tramadol and NSAIDs. Conclusions: We believe that a computerized reporting and replying system promoted the monitoring of ADRs. Antibiotics were reported most frequently as the causative agent of ADRs. Elderly patients seemed to be more susceptible to severe ADRs. With the voluntary reporting system, skin manifestations and gastrointestinal symptoms were detected successfully, while laboratory abnormalities without prominent symptoms seemed to be overlooked. Further efforts to screen for automated ADR signals are required. (Korean J Med 77:601-609, 2009)

폴리비닐실록산 치과용 인상재의 구성물로서 나노필러가 물성에 미치는 영향

김민강(Min-Kang Kim),송호준(Ho-Jun Song),김지우(Ji-Woo Kim),박영준(Yeong-Joon Park) 대한치과재료학회 2009 대한치과재료학회지 Vol.36 No.2

이혼가정 아동의 학교적응유연성과 관련된 보호요인

김민강 ( Min Kang Kim ),이희영 ( Hee Yeong Lee ),최태진 ( Tae Jin Choi ) 한국아동교육학회 2012 아동교육 Vol.21 No.2

본 연구는 이혼가정 아동의 학교적응유연성과 관련이 있는 보호요인을 탐색하는 데 그 목적이 있다. 이러한 연구 목적을 달성하기 위하여 초등학교 5,6학년 아동을 대상으로 이혼가정 아동 256명과 비이혼가정 아동 275명을 대상으로 학교적응유연성 및 자기효능감, 대인관계기술, 부모양육태도 자료를 수집하였다. 수집된 자료는 연구문제에 따라 t검증, 적률상관 및 판별분석 방법으로 통계적 분석을 수행하였다. 주요 연구 결과는 다음과 같다. 첫째, 이혼가정 아동은 비이혼가정 아동에 비하여 대체로 학교적응유연성이 낮았다. 둘째, 이혼·비이혼 가정 모두에서 아동의 학교적응유연성은 자기효능감 보호변인과 가장 높은 정적상관을 나타내었다. 그러나 다수의 보호변인들은 아동이 속한 가정의 형태(비이혼 가정, 부-동거 이혼 가정, 모-동거 이혼 가정)에 따라 학교적응유연성과의 관계에서 차이를 보였다. 셋째, 8개 보호요인을 투입변인으로 설정하여 이혼가정 아동의 학교적응유연성 수준에 대한 예측력을 분석한 결과 부-동거·모-동거 아동집단에 따라 상대적으로 관련성이 보다 높은 몇 개의 보호변인들을 확인할 수 있었다. 특히 교사지지 변인의 경우, 상관분석결과에서와 마찬가지로 모-동거 아동 집단에서 아동의 학교흥미, 규범준수, 학교유연성전체 수준을 예측할 수 있도록 해주는 중요한 보호변인으로 나타났다. This study investigated the influence of protective factors on elementary school children from divorced families. The data for this study were collected from 5th and 6th grade elementary students in Busan from 265 divorced families and 275 non-divorced families. Participants completed Scales of Self-efficacy, Interpersonal relationships, Parenting Attitude, Social Support, Family Support, Teacher Support and Friend Support. Collected data were analyzed using t-test, Pearson correlation coefficient, stepwise multiple regression and discriminant analysis. Results of this study showed that significant differences in school adjustment resilience exist between children from divorced families. This study also found that children from non-divorced families and protective factors investigated in this study were mostly statistically significantly related to school adjustment resilience regardless of family type and effectively discriminated children from divorced families and non-divorced ones. This study has important implications in that it investigated the protective factors related to children from divorced families for the first time.