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      • Impacts and Countermeasures of Climate Change on Food Supply

        Kim Chang-gil,Jeong Hak-kyun,Han Suk-ho,Kim Jeong-seung,Moon Dong-hyun 한국농촌경제연구원 2013 한국농촌경제연구원 기본연구보고서 Vol.- No.-

        Climate change has become a megatrend that will lead to significant changes in future society. Korean and overseas agencies specializing in climate forecasts predict that average global temperatures will continue to rise. While climate change may potentially have certain positive impacts for crop yields, the overall impact is predicted to be negative for environment and food security. In this context, our study aims to suggest a plan for systematically establishing a stable food supply system in Korea in respose to climate change. Various analytical models were employed, including: a response analysis based on questionnaire for farmers, panel-based analysis of the causes of pests and diseases in rice production, a random-effects model for panel data of extreme weather impact, and an analysis of food supply effects using the Simulation Model for Climate-Agriculture Relations (SIMCAR) integrated model in conjunction with the Crop Estimation through Resource and Environment Synthesis (CERES) model of the Korea Agricultural Simulation Model (KASMO). An analysis was made of major grain yields by means of the KREI-KASMO. This revealed reduced yields and area in comparison with the baseline in 2050, resulting in a reduction of rice production by 17.8%p in the RCP8.5 scenario, and reduction of soybean by 21.2%p and reduction of barley by 13.7%p in the A2 scenario. Self-sufficiency ratio of major grains in 2050 drawn from the SIMCAR revealed that the climate change scenario for rice showed 55.0% to be reduced by 18.3% in comparison with the baseline. It is predicted that selfsufficiency ratio in rice will drop to 50% which means a half of consumed rice should be imported. Key tasks for building a stable food supply system to cope with climate change were developed based on the domestic production capacity, the buffering capacity to climate change, import capacity from other countries, and policy performance capacity with reference to the empirical analysis. First, the suggested key tasks for improving the domestic production capacity include developing and disseminating adaptation technology, conserving farmland and expanding arable land, practicing climate-smart agriculture by using fusion technology, and modernizing infrastructure for agriculture. Second, key tasks for improving buffering capacity to climate change are improving resilience and biodiversity, building a risk management system, and further improving storage of food in Korea and other countries. Third, major tasks for improving the import capacity from other countries are constructing overseas food bases, effectively using the international grain market, and enhancing international cooperation with relevant countries. Finally, key tasks for improving policy performance capacity are refining and applying the climate change impact analysis model with respect to policies, expanding investments in research and development, building a vulnerability assessment system, enhancing education and training, and installing Climate Change Response Center for Agriculture (tentative). In this study, several key challenges were presented in the four different areas related to building a stable food supply system which can help overcome the challenges of climate change. It is expected that the nature of the policies that need to be prioritized and promoted, given the constraints of budget, organization and information will be addressed in future research. Also, in order for the solutions for key challenges to work properly in the field such that policy outcomes will be maximized, a consortium of research bodies in the related fields of agriculture, agricultural meteorology and agricultural economics should be created. As preparation for specific action programs. Furthermore, follow-up studies should be conducted to verify the expenses required for developing reliable climate change impact assessment models and the effectiveness of the enforced policies. Such fie

      • KCI등재

        현대(現代) 한국사회(韓國社會)에 적합한 한의학(韓醫學) "치미병(治未病)"방법(方法)에 대한 모색(摸索)

        류정아 ( Jeong Ah Lyu ),장우창 ( Woo Chang Jang ),백유상 ( You Sang Baik ),정창현 ( Chang Hyun Jeong ) 대한한의학원전학회(구 대한원전의사학회) 2011 대한한의학원전학회지 Vol.24 No.4

        In present-day Korea, a climatic change is causing various changes to the life of people and their body. The climate is more and more warm, so the internal environment of people`s body is exchanging to warm. The climatic change`s range is big and the speed is fast. So the harmony of human body is being destroyed and the human body`s adaptation ability is becoming low. At this condition, diseases more frequently occur. So doctor must expect the occur of diseases and practice early treatment. And in present-day Korea, a life environmental change is being advanced. The life environmental change is causing big changes to the people`s body and having influences to the occur of diseases. To this problem, doctor must expect and practice early treatment. This thesis would like to interpret about present-day Korea`s climatic changes and life environmental changes in Korean Medicine point of view, and try to present the method of Korean Medicine early treatment. And comment on present-day Korea`s early treatment method especially on health supplement or functional food and vaccination.

      • KCI등재

        奇恒之腑(기항지부)와 奇經八脈(기경팔맥)의 관련성 고찰

        류정아 ( Jeong Ah Lyu ),정창현 ( Jeong Chang Hyun ) 대한한의학원전학회(구 대한원전의사학회) 2014 대한한의학원전학회지 Vol.27 No.2

        Subject : The Association between Extraordinary Organs(奇恒之腑) and Eight Extra Meridians(奇經 八脈). Objectives : This study research some special aspects of Extraordinary Organs and Eight Extra Meridians which differentiated from ordinary Organs and Meridians, and the association between Extraordinary Organs and Eight Extra Meridians. Methods : First, researched classification standard and physiological characteristics of Extraordinary Organs through studying various chapters of HuangdiNeijing. Second, researched The Association between Extraordinary Organs and Eight Extra Meridians through studying on the origin of Eight Extra Meridians in HuangdiNeijing. Third, from accompanying researching the subject of Cheon-gye(天癸) and human body shape, draw synthetic hypothesis on the relationship among ordinary Meridians and Organs, muscles and skins of body shape, Extraordinary Organs and Eight Extra Meridians. Results & Conclusions : The following conclusions could be drawn. 1. Extraordinary Organs afford background for shaping human body. This is same as the properties of the earth which afford background for shaping all creations. The physiological characteristics of Extraordinary Organs is intermediation and regulation between Ki(氣) of Five Viscera & six Bowels and shape of muscles & skins in human body. 2. The origin of Eight Extra Meridians could be found in HuangdiNeijing. The collateral Meridians of the Uterus and Epiglottis Meridian are specifically formulated to supplying for the Uterus or Epiglottis. From this we can draw The Association between Extraordinary Organs and Eight Extra Meridians, that is Eight Extra Meridians are specifically formulated to supplying for Extraordinary Organs. 3. The Cheon-gye(天癸) is doing significant function in Eight Extra Meridians supplying for Extraordinary Organs. Cheon-gye concerned to growth, secondary sexual characters, generative function, aging process. Theses are all concerned with the changing of human body shape. Cheon-gye urge to change the body shape with following the human life cycle. 4. Human body has vertical symmetry because preserve its shape from the gravitational force. Eight Extra Meridians place at the middle or flank axis of human body, thus do physiological function that assistant human body have vertical symmetry shape. The purpose of shaping vertical symmetry is securing space what the inner Twelve Regular Meridians and Five Viscera & six Bowels create there own physical changes. On the other hand the inner changes need deviation between left and right because of mobility and circulation of force. But human body change the shape in the process of growth, reproduction, aging. Eight Extra Meridians play role at time of these processing, thus they deeply concerned to human’s life cycle and reproduction. 5. Eight Extra Meridians and Extraordinary Organs were named ‘Extra’ because of some special aspects which differentiated from ordinary Meridians and Organs. All they play role to have vertical symmetry shape of human body and maintain the shape, thus they deeply concerned to the change of human life cycle. These shaping maintaining and the change of human life cycle are very special aspects of human body. So they needed to differently cognize separate to the ordinary changes of Five Viscera & six Bowels and Twelve Meridians at inner space.

      • SCOPUSSCIEKCI등재

        Systematic Review of Reciprocal Changes after Spinal Reconstruction Surgery : Do Not Miss the Forest for the Trees

        Kim, Chang-Wook,Hyun, Seung-Jae,Kim, Ki-Jeong The Korean Neurosurgical Society 2021 Journal of Korean neurosurgical society Vol.64 No.6

        The purpose of this review was to synthesize the research on global spinal alignment and reciprocal changes following cervical or thoracolumbar reconstruction surgery. We carried out a search of PubMed, EMBASE, and Cochrane Library for studies through May 2020, and ultimately included 11 articles. The optimal goal of a truly balanced spine is to maintain the head over the femoral heads. When spinal imbalance occurs, the human body reacts through various compensatory mechanisms to maintain the head over the pelvis and to retain a horizontal gaze. Historically, deformity correction has focused on correcting scoliosis and preventing scoliotic curve progression. Following substantial correction of a spinal deformity, reciprocal changes take place in the flexible segments proximal and distal to the area of correction. Restoration of lumbar lordosis following surgery to correct a thoracolumbar deformity induces reciprocal changes in T1 slope, cervical lordosis, pelvic shift, and lower extremity parameters. Patients with cervical kyphosis exhibit different patterns of reciprocal changes depending on whether they have head-balanced or trunk-balanced kyphosis. These reciprocal changes should be considered to in order to prevent secondary spine disorders. We emphasize the importance of evaluating the global spinal alignment to assess postoperative changes.

      • KCI등재

        임플란트의 collar design이 변연골과 연조직에 미치는 영향

        유현상,강선녀,정창모,윤미정,허중보,전영찬 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.1

        연구 목적: 임플란트 경부가 잘 설계된 경우 양호한 연조직 반응을 통해 변연골을 보존하는데 도움이 된다. 본 실험에서는 연, 경조직 경계부에 가장 가까이 위치하는 임플란트의 collar design이 변연골 변화와 연조직 반응에 미치는 영향을 동물실험을 통해 알아보고자 하였다. 연구 재료 및 방법: 2마리의 건강한 Beagle dog에 임플란트 collar design만 다른 두 종류의 임플란트(Neobiotech Co. Seoul, Korea)를 식립하였다. Collar에 bevel 을 부여한 군(Bevel 군)과 "S"자 형태를 부여한 군(Bioseal 군)으로 나누어 마리 당 7개, 군당 7개, 총 14개의 임플란트를 무작위로 식립한 후 Healing abutment를 즉시 체결하였다. 디지털 표준구내 방사선사진을 이용해 4주 간격으로 총 12주간 근원심 변연골 변화를 관찰하였고, 12주에 희생하여 조직학적 분석을 통해 협설 변연골 흡수 및 임플란트 주변 연조직 반응을 평가하였다. Mann-Whitney test를 통해 동일한 방사선 사진 촬영 시점에서 근원심 변연골 변화량 및 조직계측치를 군 간 비교하였고, Kruskal-Wallis test를 통해 방사선 사진상 근원심 변연골 변화량이 시간에 따른 차이가 있는지 군 내 분석 한 후 Duncan test를 통해 사후 검증하였다(α=.05). 결과: 방사선학적 분석 결과 각 촬영 시점에서 두 군간 근원심 변연골 변화량의 차이를 보이지 않았다(P>.05). 군 내에서 시간에 따른 근원심 변연골의 흡수량을 분석한 결과 Bevel 군에서는 시간에 따른 차이를 보이지 않았으나 (P>.05), Bioseal 군에서는 시간에 따른 차이를 보였으며, 4주및8주와 비교했을 때 12주에서 변연골의 증가를 보였다(P<.05). 조직학적 분석 결과 협설측 변연골 흡수량에서 두 군간 차이를 보이지 않았으나 (P>.05), Bevel 군에 비해 Bioseal 군에서 더 견고한 결합조직부착을 관찰할 수 있었으며, 생물학적 폭경의 값은 두 집단 간 차이를 보이지 않은 반면에 (P>.05), 접합상피부착은 Bevel 군에서 유의하게 길었고, 결합조직부착은 Bioseal 군에서 더 길게 나타났다(P<.05). 결론: Bevel 군에 비해 Bioseal 군에서 결합조직부착은 길게 형성된 반면에 접합상피부착은 더 짧게 나타났으며, 생물학적 폭경과 초기 변연골 흡수에는 차이가 없음을 알 수 있었다. 연조직 반응의 차이가 실제 기능하중 하에서 변연골 변화에 미치는 영향에 대해서 향후 연구가 필요할 것으로 생각된다. PURPOSE. The purpose of this study was to investigate the effects of implant collar design on marginal bone change and soft tissue response by an animal test. MATERIALS AND METHODS. Two types of Implant (Neobiotech Co. Seoul, Korea) that only differs in collar design were planted on two healthy Beagle dogs. The implants were divided into two groups, the first group with a beveled collar (Bevel Group) and the second group with "S" shaped collar (Bioseal group). Standardized intraoral radiographs were used to investigate the mesio-distal change of the marginal bone. Histological analysis was done to evaluate the bucco-lingual marginal bone resorption and the soft tissue response adjacent to the implant. Mann-Whitney test was done to compare the mesio-distal marginal bone change at equivalent time for taking the radiographs and the tissue measurements between the groups. RESULTS. Radiographic and histological analysis showed that there was no difference in marginal bone change between the two groups (P>.05). Histological analysis showed Bioseal group had more rigid connective tissue attachment than the Bevel group. There was no difference in biological width (P>.05). Bevel group showed significantly longer junctional epithelium attachment and Bioseal group showed longer connective tissue attachment (P<.05). CONCLUSION. For three months there were no differences in marginal bone change between the Bevel group and the Bioseal group. As for the soft tissue adjacent to the implant, Bioseal group showed longer connective tissue attachment while showing shorter junctional epithelium attachment. There were no differences in biologic width.

      • 수정진동자를 이용한 박막의 상거동 분석

        장상목,김종민,이현우,정재헌 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

        This paper shows that an AT-cut quartz crystal analyzer(Q.C.A) can be applied to the investigation of the microheological change of the polymer blend solution during solvent evaporation process casting blend on the surface of quartz crystal. he blend is made from various compositions of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate)(PVAc), and ethyl acetate as slovent. The resonant frequency and resonant admittance of the blend casting Q.C.A are measured simultaneously and the microheological behavior of the blend is analyzed during ethyl acetate evaporation. The PMMA/PVAc blend solution behaves several informative changes of resonant frequency and resonant admittance during ethyl acetate evaporation, depending on the evaporation time and the blend ratio. The PMMA/PVAc blend solution in ethyl acetate exhibited critical changes of resonant frequency and resonant admittance depending on the evaporation time and blend ratio. From this study, it is known that the quartz crystal analyzer can be successfully applicable to analyze viscoelastic changes on the microrheology and phase separation at the initial stage of the blends of PMMA and PVAc during the solvent, ethyl acetate evaporation process by maesuring the resonant freaquency and the resonant resistance in situ.

      • 神에 대한 硏究 : ≪黃帝內徑≫을 中心으로 focus on ≪Huangdineijing(黃帝內徑)≫

        丁彰炫,朴贊國 慶熙大學校韓醫科大學韓醫學硏究所 1996 慶熙韓醫大論文集 Vol.19 No.2

        This thesis was written in order to help set the groundwork of a new medicine based on Shin(神). This new medicine is an advanced system of Hyung(形) focused western medicine and Ki(氣) oriented eastern medicine. In this thesis, I examined the text, 《Huangdineijing(黃帝內經)》and analyzed the important points relating to Shin(神), such as classification, faculty, properties. Shin(神) in 《Huangdineijing(黃帝內經)》is classified according to either its hierarchy or its faculty. Hierarchically, Shin(神) in 《Huangdineijing(黃帝內經)》has two levels; "Cosmos Shin"(天神) and "Human Shin"(人神). Cosmos Shin(天神), which is the "Great Law" is the basis of creation, change, development, extinction of all things in the universe including human. "Human Shin" which represents Shin(神) at the mundane level is the "Basic Principle" of human life, speaking broadly and mental function in a narrow sense. In terms of faculty, Shin(神) in 《Huangdineijing(黃帝內經)》is divided into Shin-myung(神明), Shin-ki(神氣) and Jeong-Shin(精神). Shin-myung(神明) is not only the "Basic Law" which has control over the movements and changes of the universe, but also the "Basic Principle" of human life. Shin-ki(神氣), it can be said, forms of Shin's expression. It means that Shin(神) reveals itself by means of Ki(氣). Jeong-Shin(精神) means mental function which dwells in the body and has a control over thinking, consciousness and judgment. In other words, Shin-myung(神明) indicates Shin's property of controlling or regulating, Shin-ki(神氣) indicates Shin's activity, and Jeong-Shin(精神) indicates both the Shin(神) and body united. In conclusion, all of the aforementioned are only classifications dividing the one Shin(神). Although the Shin may be classified according to the particular situation, it is still the one Shin.

      • Effect of Extreme Heatwaves on the Mortality and Cellular Immune Responses of Purplish Bifurcate Mussel Mytilisepta virgata (Wiegmann, 1837) (=Septifer virgatus) in Indoor Mesocosm Experiments

        Hyun-Ki Hong,Chang Wan Kim,Jeong-Hwa Kim,Nobuhisa Kajino,Kwang-Sik Choi 제주대학교 해양과학연구소 2021 해양과환경연구소 연구논문집 Vol.45 No.-

        In the rocky intertidal environment, the frequency and duration of heatwaves have increased over the last decade, possibly due to global climate change. Heatwaves often result in lethal or sub-lethal disturbances in benthic animals by changing their metabolic activities. In this study, we investigated the impacts of extreme heatwave stress on the hemocyte functions of Mytilisepta virgata and subsequent mortality to gain a better understanding of the potential causes and consequences of mass mortality events in this mussel during summer. We discriminated three types of hemocytes in the hemolymph, granulocytes, hyalinocytes, and blast-like cells, using flow cytometry and revealed that granulocytes were the major hemocyte involved in cellular defensive activities, such as phagocytosis and reactive oxygen species (ROS) production. For the experiment, mussels were exposed to a 40◦C air temperature for 12 h per day over 5 days under laboratory conditions as a simulated semi-diurnal tidal cycle. Mortality began to occur within 3 days after beginning the experiment, and all mussels had died by the end of the experiment. Flow cytometry indicated that the mussels exposed to high air temperatures produced significantly more ROS than did the control mussels within 2 days after the onset of the experiment, which may have caused oxidative stress. Such high levels of ROS in the hemolymph increased DNA damage in hemocytes after 3 days of exposure and decreased the phagocytosis of hemocytes 4 days after the experiment began. The observed mortality and decline in immune capacity suggested that an extreme heat event occurring in the rocky intertidal ecosystem during summer could exert sublethal to lethal impacts on macrobenthic animals.

      • KCI등재

        2 ㎓ 선형 위상 천이 특성을 갖는 소형 아날로그 위상천이기

        오현석(Hyun-Seok Oh),최재홍(Jae-Hong Choi),정해창(Hae-Chang Jeong),허윤성(Yun-Seong Heo),염경환(Kyung-Whan Yeom) 한국전자파학회 2011 한국전자파학회논문지 Vol.22 No.1

        본 논문에서는 2 ㎓ 선형 위상 천이 특성을 갖는 위상천이기를 설계 및 제작하여 보였다. 소형의 위상 천이기 구현을 위해 집중소자로 구성된 전통과 회로망(all pass network)을 기반으로 위상천이기를 구성하고, 박막 세라믹 공정을 이용하여 제작하였다. 또한, 선형의 위상 천이 특성을 얻기 위해 버랙터(varactor) 다이오드에 직렬 커패시터를 연결하여, 전압에 대한 커패시턴스를 선형화함으로써 비선형성을 개선하였다. 전통과 회로망에 나타나는 인덕터는 스파이럴 인덕터로 구현하고, 이를 다이오드 바이어스 회로에 활용하여 4 ㎜×4 ㎜ 면적을 가지는 소형 위상천이기를 구성할 수 있었다. 또한, 온-웨이퍼(on wafer)로 측정을 위해 입출력은 CPW(Coplanar Waveguide) 형상으로 구현하였으며, 제작된 위상천이기는 버랙터 조정 전압 0~5 V에 대하여, 2 ㎓에서 삽입 손실은 약 4.2~4.7 ㏈, 위상 변화량은 약 79°였으며, 예상한대로 선형 위상 천이 특성을 보였다. In this paper, we present a 2 ㎓ compact analog phase shifter with linear phase-tune characteristic. The compact phase shifter was designed base on a lumped all pass network and implemented using a ceramic substrate fabricated with thin-film technique. For a linear phase-tune characteristic, a capacitance of the varactor diode for a tuning voltage was linearized by connecting series capacitor and subsequently produced an almost linear capacitance change. The inductor and bias circuit in the all pass network was implemented using a spiral inductors for small size, which results in the size reduction to 4 ㎜×4 ㎜. In order to measure the phase shifter using the probe station, two CPW pads are included at the input and output. The fabricated phase shifter showed an insertion loss of about 4.2~4.7 ㏈ at 2 ㎓ band and a total 79° phase change for DC control voltage from 0 to 5 V, and showed linear phase-tune characteristic as expected in the design.

      • KCI등재후보

        상피성 암세포주에 대한 녹차 Catechin의 효과

        박정현(Jeong Hyun Park),김대중(Dae Joong Kim),한장희(Jang Hee Hahn),김홍태(Hong Tae Kim),정용욱(Yong Wook Jung),성훈기(Hoon Ki Sung),김주영(Joo Young Kim),송인환(In Hwan Song),성언기(Eon Gi Sung),이융창(Yung Chang Lee) 대한해부학회 2001 Anatomy & Cell Biology Vol.34 No.5

        Catechin은 녹차에서 추출되는 폴리페놀의 주요성분으로 고혈압 및 동맥경화의 예방효과, 당뇨억제효과, 항산화작용, 항암작용 등에 직접 관여하는 물질이다. 본 연구에서는 태평양에서 제공받은 녹차 catechin을 이용하여 상피성 암세포주인 A549 (폐암)와 EATC (복수암)세포에 투여한 후 처리농도와 시간에 따른 변화를 비교, 관찰함으로써 녹차의 효과와 작용기전을 밝혀내는데 목적이 있었다. 본실험은 A549 세포와 EATC 세포를 배양한 후 녹차 catechin을 1, 10, 100, 500 μg/ml의 농도로 48시간 동안 처리하였고, 광학현미경, 공초점현미경, 전자현미경 등을 이용하여 세포의 구조적 변화를 확인하였으며 MTT분석, 전기영동, 유세포분석기 등을 사용하여 세포 손상정도를 파악하였다. A549 세포에서는 catechin 1 μg/ml와 10 μg/ml 농도에서는 대조군에 비하여 큰 변화를 관찰할 수 없었다. 100 μg/ml catechin을 처리하였을 때 세포내의 검은 과립들의 수가 증가하였고 층판소체의 손상이 나타났다. 세포주기의 장애가 나타나 DNA 합성전기에 있는 세포들의 수가 급격히 증가하였다. 500 μg/ml 농도에서는 층판소체와 사립체의 파괴가 심하게 나타났으며 세포생존율이 감소하였고 세포주기의 장애도 관찰되었다. EATC 세포에서는 catechin의 농도가 A549 세포의 경우보다 낮은 농도에서도 세포증식 억제 및 세포손상 효과가 나타났다. 10 μg/ml 농도에서도 세포의 위축과 생존율의 감소가 일어났으며 전기영동상에 괴사되는 세포들이 파악되었다. 100μg/ml catechin을 처리하였을 때 자연사의 형태학적 관찰, 전기영동, 유세포분석 등에서 자연사 과정에 있는 세포들이 많이 나타났다. 결과적으로 녹차 catechin을 배양한 상피성 암세포에 투여함으로서 세포의 생존율과 증식이 억제되었고 그 과정에서 괴사, 자연사, 세포주기의 장애 등이 관여하는 것으로 생각된다. 그러나 일련의 세포손상과정을 유도하는 데 있어 세포의 종류, 처리 시간, 농도에 따라 다소 차이가 있음을 확인하였다. Catechin is main component of polyphenol extracts from green tea, it is associated with prevention of hypertension and atherosclerosis, anti-diabetic effect, antioxidant, antitumor. The purpose of this research is to investigate the effect and its mechanism of green tea catechin on epithelial cancer cell lines in various concentrations and durations. For this study, epithelial cancer cell lines, A549 (lung cancer), EATC (Ehrlich-Lettre ascites tumor cell) were used. Inverted, light, confocal and electron microscopes were applied to find morphological changes. MTT assay, flowcytometric analysis, gel electrophoresis were used to compare severity of cellular damages to control after exposure to 1, 10, 100 and 500 μg/ml catechin for 48 hours. In the A549 cells, after 1 μg/ml and 10 μg/ml catechin treatments, there was no notable changes. However, exposure to 100 μg/ml catechin induced increase of cytoplasmic granules, destruction of lamellar body, inhibition of cell cycle, especially G0/G1. In the early phase of 500 μg/ml catechin administration, decrease of cell population, severe destruction of lamellar bodies and mitochondria, derangement of cell cycle were shown. In the EATC, such as those effects occurred after exposure to lower concentration of catechin than in that of A549 cells. After exposure of 10 μg/ml catechin, rounded-up cells and necrotic cells were found. Whereas, most of cells were under apoptotic changes-cytoplasmic condensation, nuclear fragmentation, cellular shrinkage, ladder pattern in the electrophoresis, when administrated 100 μg/ml catechin. These results suggested that exposure of catechin induced severe cellular damage and growth inhibition in dose- and time-dependent manner. And we confirmed that these effects of catechin were involved with apoptosis, necrosis and cell cycle arrest and were quite different according to cancer type. Therefore, much more research would be demanded before clinical application of catechin to human cancer therapy and this study would be the basic source for further study of green tea.

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