그라비올라로부터 분리된 Kaempferol 및 Nicotiflorin의 ¹O₂으로 유도된 세포손상에 대한 보호 효과와 그 메커니즘

박소현 ( So Hyun Park ),신혁수 ( Hyuk Soo Shin ),이난희 ( Nan Hee Lee ),홍인기 ( In Kee Hong ),박수남 ( Soo Nam Park ) 한국공업화학회 2018 공업화학 Vol.29 No.1

본 연구에서는 그라비올라의 주성분인 nicotiflorin을 분리하고 그 아글리콘 성분인 kaempferol을 얻어 세포 보호 효과 및 그 보호 메커니즘을 규명하였다. L-Ascorbic acid 및 (+)-α-tocopherol을 대조군으로 하여, ¹O₂로 유도된 세포 손상에 대해 nicotiflorin 및 kaempferol의 보호 효과를 측정한 결과 nicotiflorin < (+)-α-tocopherol < kaempferol 순으로 보호 효과가 증가하였다. L-Ascorbic acid는 세포 보호 효과를 보이지 않았다. 이들의 세포 보호 효과 메커니즘을 밝히기 위해 singlet oxygen 소광 속도 상수, 자유라디칼 소거 활성, ROS 소거 활성 및 적혈구 세포 침투율을 측정하였다. 실험 결과, kaempferol과 그 배당체인 nicotiflorin의 세포 보호 효과에 있어서 큰 차이는 세포막에의 침투가 가장 큰 요인으로 확인되었다. 대조군 L-ascorbic acid가 항산화능은 크지만 실험 조건에서 세포막에 침투가 잘 안되어 세포 보호 효과가 나타나지 않은 것으로 확인되었다. Kaempferol과 (+)-α-tocopherol의 비교를 통해 세포 침투뿐만 아니라 라디칼 소거활성 및 ROS 소거 활성도 세포 보호 효과에 기여하는 것으로 나타났다. 결론적으로, 광증감 반응으로 유도된 세포막 파괴에 대한 보호작용은 항산화제들의 세포 침투, 자유라디칼 및 ROS 소거 활성이 큰 영향을 미치는 것으로 확인되었다. In this study, we investigated the cellular protective effects and mechanisms of nicotiflorin and its aglycone kaempferol isolated from Annona muricata. The protective effect of these components against ¹O₂-induced cell damage was also studied by using L-ascorbic acid and (+)-α-tocopherol as controls. Kaempferol exhibited the most potent protective effect, followed by (+)-α- tocopherol and nicotiflorin. L-Ascorbic acid did not exhibit any cellular protective effects. To elucidate the mechanism underlying protective effects, the quenching rate constant of the singlet oxygen, free radical-scavenging activity, ROS-scavenging activity, and uptake ratio of the erythrocyte membrane were measured. The results showed that the cell membrane penetration is a key factor determining the cellular protective effect of kaempferol and its glycoside nicotiflorin. The result from L-ascorbic acid demonstrated that the cellular protective effect of a compound depends on its ability to penetrate the cell membrane and is independent of its antioxidant capacity. In addition, it is suggested that cellular protective effects of kaempferol and (+)-α- tocopherol depend not only on the cell permeability, but also on free radical- and ROS-scavenging activities. These results indicate that the cell permeability and free radical- and ROS- scavenging activities of antioxidants are major factors affecting the protection of cell membranes against the oxidative damage induced by photosensitization reaction.

대학생들의 스마트폰을 통한 음란물유통 행위의 설명 : 위험요인과 보호요인의 상호작용효과와 성별 차이를 중심으로

이지선,이성식 대한범죄학회 2019 한국범죄학 Vol.13 No.3

This study constructs a model for university students’ distribution of sexually explicit material on smart phone usage and tests interaction effects between risk and protective factors. Risk factors include low self-control, differential association with peers, and peer’s pushing and protective factors include negative attitude toward distribution of sexually explicit material and informal social control. Then, this study investigates the interaction effects between them in explaining distribution of sexually explicit material. Furthermore, this study analyses gender differences in their interaction effects. Using data from 608 male and female university students in Seoul, this study found that low self-control has a significant effect on distribution of sexually explicit material in male but not in female. Result also show that association with peers has a not a significant effect but peer’s pushing has a significant effect on distribution of sexually explicit material in male, while both peer factors have significant effects on it in female. In testing the interaction effects between risk and protective factors, it is shown that the moderating effect of individual attitude is larger in female than in male, even though its effect is significant in both groups. However, it is shown that the moderating effect of informal control is low in male, even though the interaction effect between peer’s pushing and informal control is little significant. However, it is found that the interaction effects between peer factors and informal control are positively significant in female. 본 연구는 대학생을 대상으로 스마트폰을 통한 음란물유통 행위를 설명하기 위해 위험요인과 보호요인을 포함하는 연구모델을 제시하였고 남녀에 따라 차이가 있는지를 살펴보았다. 본 연구에서는 위험요인으로 낮은 자기통제력, 음란물유통 친구와의 접촉, 친구강요를 설정하였고, 보호요인으로는 음란물유통에 대한 부정적 도덕태도와 외적 통제로서 구성원들에 의한 비공식통제를 설정했으며 위험요인과보호요인이 상호작용효과를 가질 것인지 그리고 그 작용이 남녀에 따라 상이할 것인지의 연구문제를제시했다. 서울시 열 개 대학 608명을 대상으로 조사한 자료의 분석결과에서 남성의 음란물유통 행위에서는 낮은 자기통제력이 유의미한 영향을 가졌지만 여성의 경우 낮은 자기통제력이 영향을 미치지 못해 차이를 보였다. 다음으로 음란물유통에 대한 친구요인을 보면 남성의 경우 친구와의 접촉은 유의미한 영향을 미치지 못했으나 친구강요는 유의미한 영향을 미쳤고 여성의 경우는 음란물유통 친구접촉과 친구강요 모두가 음란물유통 행위에 유의미한 영향을 미쳤다. 이처럼 남성은 낮은 자기통제력이, 여성에 게는 친구요인이 상대적으로 더 중요했고 남녀 모두 친구강요가 중요했다. 위험요인과 보호요인과의 상호작용효과를 살펴보면 남성의 경우 낮은 자기통제력과 도덕태도와의 상호작용효과가 나타난 반면, 여성은 친구접촉 및 친구강요와 태도와의 상호작용효과가 높은 수준에서 나타났다. 이는 남녀 모두에서 도덕태도가 조절변인으로 작용하지만 여성에게 더 중요한 보호요인이라는 것을 제시해 본 예측과 일치했다. 그 대신 또 다른 보호요인으로 구성원들의 비공식통제는 남성에서 더 중요할 것이라고 예상했지만 친구강요와 비공식통제가 약한 수준에서만 상호작용효과를 나타내 크게 지지하지는 못했다. 그리고 오히려 여성에서는 친구접촉, 친구강요와 비공식통제가 정(+)적으로 상호작용효과가 나타났다.

정보보호 통제활동이 조직유효성에 미치는 영향

정구헌(Gu Heon Jeong),정승렬(Seung Ryul Jeong) 한국지능정보시스템학회 2011 지능정보연구 Vol.17 No.1

This study was designed to empirically analyze the effect of control activities(physical, managerial and technical securities) of information protection on organizational effectiveness and the mediating effects of information application. The result was summarized as follows. First, the effect of control activities(physical, technical and managerial securities) of information protection on organizational effectiveness showed that the physical, technical and managerial security factors have a significant positive effect on the organizational effectiveness(p < .01). Second, the effect of control activities(physical, technical and managerial securities) of information protection on information application showed that the technical and managerial security factors have a significant positive effect on the information application(p < .01). Third, the explanatory power of models, which additionally put the information protection control activities(physical, technical and managerial securities) and the interaction variables of information application to verify how the information protection control activities( physical, technical and managerial security controls) affecting the organizational effectiveness are mediated by the information application, was 50.6%~4.1% additional increase. And the interaction factor(β = .148, p < .01) of physical security and information application, and interaction factor(β = .196, p < .01) of physical security and information application among additionally-put interaction variables, were statistically significant(p < .01), indicating the information application has mediated the relationship between physical security and managerial security factors of control activities, and organizational effectiveness. As for results stated above, it was proven that physical, technical and managerial factors as internal control activities for information protection are main mechanisms affecting the organizational effectiveness very significantly by information application. In information protection control activities, the more all physical, technical and managerial security factors were efficiently well performed, the higher information application, and the more information application was efficiently controlled and mediated, which it was proven that all these three factors are variables for useful information application. It suggested that they have acted as promotion mechanisms showing a very significant result on the internal customer satisfaction of employees, the efficiency of information management and the reduction of risk in the organizational effectiveness for information protection by the mediating or difficulty of proved information application.

삼두해정탕가미방이 $CCl_4$ 및 d-Galactosamine에 依하여 誘發된 흰쥐의 肝損傷에 미치는 影響

강재춘,이상민,Kang, Jae-Chun,Lee, Sang-Min 대한한방내과학회 1999 大韓韓方內科學會誌 Vol.20 No.1

In order to investigate the protective effect of Samduhaejungtang-gamibang on the liver injury of rats induced by $CCl_4$ and d-galactosamine, the serum transaminase(GOT& GPT) alkaline phosphatase(ALP), lactic dehydrogenase(LDH) for enzyme activities and triglyceride, total bilirubin amounts for serum component were measured. All animals were divided into 4 groups, those were normal group(untreated), control group(treated with vehicle 0.9% Saline solution), sample Ⅰ group(1500mg/kg administrated), sample Ⅱ group(3000mg/kg administrated). The results were as follows: 1. The inhibitory effects of the serum GOT activities in rats induced by $CCl_4$ were noted in sample Ⅱ group(p<0.01). In serum GPT activities, sample Ⅱ group(p<0.05) only showed the inhibitory effects. 2. The inhibitory effects of the serum ALP activities in rats induced by $CCl_4$ were noted in sample Ⅱ group(p<0.01) 3. The inhibitory effects of the serum LPH activities in rats induced by $CCl_4$ were noted in sample Ⅱ group, but it is not recognized statistically. 4. The increases effects of the serum triglyceride content level in rats induced by $CCl_4$ were inhibited in both sample Ⅰ group(p<0.05) and sample Ⅱ group(p<0.01) 5. The increases effects of the serum total bilirubin content level in rats induced by $CCl_4$ were inhibited in sample Ⅱ group(p<0.05) 6. The inhibitory effects of the serum GOT, GPT activities in rats induced by d-galactosamine were noted in sample Ⅱ group (p<0.001), but sample Ⅰ group was not recognized. 7. The signiticantly inhibitory effects of in the serum LDH activities in rats induced by d-galactosamine were noted in both sample Ⅰ group(p<0.05) and sample Ⅱ group (p<0.001) 8. The increases of the serum ALP content level in rats induced by d-galactosamine were inhibited in sample Ⅱ group(p<0.05) 9. The increases of the serum total bilirubin content level in rats induced d-galactosamine were inhibited in sample Ⅱgroup(p<0.05) According to the above results, it is considered that Samduhaejungtang-gamibang has protective effect against liver injury in rats induced by $CCl_4$ and d-galactosamine. So it is required to study about the actions of mutual relation of medicines and patho-mechanism by experiment.

Estimating the Protection Effects of Antidumping Dutiesa

이홍구 한국무역학회 2009 Journal of Korea trade Vol.13 No.3

It is estimated in this paper that AD duties provide import protection. AD duties installed by the United States during the period of 1990-1996 have caused a fall in the amount of imports from the targeted countries in industries concerned. At the same time, AD duties have brought about the import diversion effect. Yet import diversion falls short of import reduction on average, so that import protection took place following the imposition of AD duties. Comparing the result of this paper with those of Staiger and Wolak (1994) leads to the conjecture that the import protection effect of U.S. AD measures does not change much from the period 1980-1985 to the period 1990-1996. When it comes to sectoral or country-wise protection, the protection effect is not homogeneous. It is unevenly felt by different local producers depending on which industries from which countries are targeted when AD duties are imposed. Keywords: Antidumping Duties, Import Reduction, Import Diversion, Protection Effect 8 I. Introduction A decrease in the importance of tariffs as a trade policy tool has induced antidumping (AD) measures to be used intensively by a growing number of countries. AD measures have been preferred to any other protection instruments as a means of protecting particular industries from external competition. It is estimated in this paper that AD duties provide import protection. AD duties installed by the United States during the period of 1990-1996 have caused a fall in the amount of imports from the targeted countries in industries concerned. At the same time, AD duties have brought about the import diversion effect. Yet import diversion falls short of import reduction on average, so that import protection took place following the imposition of AD duties. Comparing the result of this paper with those of Staiger and Wolak (1994) leads to the conjecture that the import protection effect of U.S. AD measures does not change much from the period 1980-1985 to the period 1990-1996. When it comes to sectoral or country-wise protection, the protection effect is not homogeneous. It is unevenly felt by different local producers depending on which industries from which countries are targeted when AD duties are imposed. Keywords: Antidumping Duties, Import Reduction, Import Diversion, Protection Effect 8 I. Introduction A decrease in the importance of tariffs as a trade policy tool has induced antidumping (AD) measures to be used intensively by a growing number of countries. AD measures have been preferred to any other protection instruments as a means of protecting particular industries from external competition.

B103 세포에서 베타아밀로이드(25-35) 독성에 대한 Ginsenoside Rb_l과 Rg_l의 보호효과

이은아,주인수,허균,묵인희 대한신경과학회 1999 대한신경과학회지 Vol.17 No.5

플라보노이드 luteolin이 세포자멸사 관련 단백질 활성 억제를 통해 6-hydroxydopamine 세포독성에 미치는 억제효과

이선화,강진호,한정호,김두응,이정수 대한신경과학회 2012 대한신경과학회지 Vol.30 No.4

Background: Flavonoid luteolin has been shown to exhibit cell protective effect. However, it is still uncertain whether the effect of luteolin on cellular toxicity of the parkinsonian toxin 6-hydroxydopamine is mediated by apoptosis-related protein activation. Methods: In differentiated PC12 cells exposed to 6-hydroxydopamine in combination with luteolin, we observed the apoptosis-related protein activation, nuclear damage, formation of reactive oxygen species and cell death. Results: 6-Hydroxydopamine caused apoptosis by inducing a decrease in Bid, Bcl-2, Bcl-xL and survivin levels, increase in Bax levels, cytochrome c release and activation of caspases. Treatment with luteolin reduced changes in the apoptosis-related protein levels, formation of reactive oxygen species, nuclear damage and cell death. Conclusions: Luteolin may reduce the 6-hydroxydopamine-induced apoptosis in differentiated PC12 cells by suppressing the activation of the caspase-8- and Bid-dependent pathways and the mitochondria-mediated apoptotic pathway, leading to caspase activation. The preventive effect of luteolin may be associated with its inhibitory effect on the production of reactive oxygen species. Luteolin may attenuate the oxidative stress and mitochondrial dysfunction-induced neuronal cell death take place in Parkinson’s disease. Background: Flavonoid luteolin has been shown to exhibit cell protective effect. However, it is still uncertain whether the effect of luteolin on cellular toxicity of the parkinsonian toxin 6-hydroxydopamine is mediated by apoptosis-related protein activation. Methods: In differentiated PC12 cells exposed to 6-hydroxydopamine in combination with luteolin, we observed the apoptosis-related protein activation, nuclear damage, formation of reactive oxygen species and cell death. Results: 6-Hydroxydopamine caused apoptosis by inducing a decrease in Bid, Bcl-2, Bcl-xL and survivin levels, increase in Bax levels, cytochrome c release and activation of caspases. Treatment with luteolin reduced changes in the apoptosis-related protein levels, formation of reactive oxygen species, nuclear damage and cell death. Conclusions: Luteolin may reduce the 6-hydroxydopamine-induced apoptosis in differentiated PC12 cells by suppressing the activation of the caspase-8- and Bid-dependent pathways and the mitochondria-mediated apoptotic pathway, leading to caspase activation. The preventive effect of luteolin may be associated with its inhibitory effect on the production of reactive oxygen species. Luteolin may attenuate the oxidative stress and mitochondrial dysfunction-induced neuronal cell death take place in Parkinson’s disease.

청소년의 위험행동과 위험요인간의 관계에서 보호요인의 매개효과

전종국 한국소년정책학회 2011 少年保護硏究 Vol.17 No.-

The purpose of this study was to verify the mediating effects of protective factors between adolescent's risk behavior and risk factors. In total, 510 high school students participated in the survey. For this study the correlation analysis, the multiple regression, the structural equation model analysis were conducted. SPSS WIN 12.0 and AMOS 5.0 were used. The results are summed up as follows. First, the stepwise regression was conducted to examine what is the factor that explains the risk behavior of adolescents among risk factors, and as a result, four variables such as peers' negative pressure, risk factors of school, sensation seeking tendency and risk factors of family were statistically significant, and the total explanation variable about the risk behavior was 26.8%. The variables had powerful explanation in the order of peers' negative pressure, risk factors of school, sensation seeking tendency and risk factors of family. However psychological and emotional factors were not included in the regression model. Second, as a result of the examination of which factor explains the risk behavior of adolescents among protective factors, two variables such as management and supervision of parents and positive experiences in school were statistically significant, and the total explanation variable about the risk behavior was 12.1%. The variables had powerful explanation in the order of management and supervision of parents and positive experiences in school. However, self-esteem, peers' support and active measure strategy were not included in the regression model. At last, the mediation effect of protective factors was verified in the relationship between risk factors and protective factors. For this the structural equation model analysis was used. As a result, there was a direct effect of risk factors on the risk behavior of adolescents, but, the partial mediation effect model in which protective factors mediate risk factors and the risk behavior of adolescents had more powerful explanation about the risk behavior of adolescents than the model with only the direct effect.

빈곤청소년의 학교적응유연성에 대한 보호요인의 조절효과

김순규 한국청소년학회 2009 청소년학연구 Vol.16 No.10

This study investigates the moderating effect of protective factors on school resilience of poor adolescents. For this, the study divided poverty, poverty-related risk factors as risk factors, and use protective factors to contain individual, family, school level. The data for this study came from Korean Youth Panel Survey(KYPS), a prospective longitudinal survey was administered annually by the Korea Institute for Youthe Development(KIYD). The sample used in the research consists of 1st and 2nd year survey for 3,209 junior high 2nd grader. In addition, I used the Mplus program as analysis method. The results are as follows: First, poverty, poverty-related risk factots, protective factors effect on school resilience of poor adolescents. Second, protective factors act as buffers against the negative effects of poverty on school resilience by moderating effect. In conclusion, various theoretical and practical implications of these results were discussed. 청소년에게 있어 빈곤은 경제적 어려움 이상으로 발달에 심각한 영향을 주는 요인이다. 이에 빈곤과 관련한 청소년 연구가 지속적으로 이루어지고 있으며, 특히 빈곤이라는 위험상황에서도 성공적으로 적응하는 특성 및 과정으로써 빈곤청소년의 적응유연성 연구가 활발히 이루어지고 있다. 그러나 이러한 연구들은 빈곤청소년의 다양한 적응유연성 메커니즘을 설명하지 못함으로써, 실천적 한계를 가지고 있다. 이에 본 연구는 청소년의 발달단계를 고려하여 학교에 초점을 두고, 빈곤에 처한 청소년의 학교적응유연성에 대한 보호요인의 조절효과를 살펴보고자 하였다. 구체적으로 본 연구는 위험요인을 빈곤과 빈곤관련 위험요인으로 분류하였으며, 개인, 가족, 학교차원에서 측정된 보호요인의 조절효과를 살펴보았다. 이를 위해 2003년~2004년도의 한국청소년패널조사(KYPS) 자료(중학생 대상)를 사용하였으며, 분석방법으로 구조방정식 프로그램인 Mplus를 사용하였다. 분석결과, 빈곤, 빈곤관련 위험요인, 보호요인 모두 학교적응유연성에 유의미한 영향을 미치는 것으로 나타났으며, 보호요인의 조절효과를 확인할 수 있었다. 마지막으로 이러한 연구결과를 통해 결론에서 이론적, 실천적 함의를 살펴보았다.

Matrix Enhancement Effect: A Blessing or a Curse for Gas Chromatography?

심재한 ( Jae Han Shim ) 한국환경농학회 2013 한국환경농학회 학술대회집 Vol.2013 No.-

The matrix enhancement effect in gas chromatography (GC) has been a problem for the last decade as it results in unexpected high recovery. Most of the efforts, including the use of different types of injectors/matrix simplification procedure, and further clean-up associated with removing this effect was focused on equalizing the response of the standard in the solvent and matrix. However, after eliminating the matrix enhancement effect, the sensitivity of GC remained unchanged. But, GC sensitivity can be increased by utilizing this matrix effect originating from a matrix matched standard. Very few studies have highlighted utilizing the matrix effect but have rather advocated eliminating it. Analyte protectants (3-ethoxy-1, 2-propanediol, gulonolactone and sorbitol) have been introduced as an alternative for GC-mass spectroscopy (GC-MS) (not examined for other GC detectors), as they equalize the response without removing the matrix effect, and, hence, increase sensitivity. Versatile applications of analyte protectants are not observed in practice. The European guidelines recommend use of matrix matched standard calibration for residue measurements. As a result, numerous applications are available for matrix matched standards that compensate for the matrix effect. Moreover, the matrices (among them pepper leaf matrix) can act as a protectant for thermolabileanalytes in some cases. A lower detection limit should be achieved from the GC detector to comply with the maximum residue limits. Therefore, the matrix enhancement effect, which is considered a problem, can play an important role in lowering the detection limit by increasing the transfer of analyte from the injection port to the detector.