• Toxicological Research
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• 제26권4호
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• pp.245-252
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• 2010

Epithelial-mesenchymal transition (EMT) is a complex process in which epithelial cells acquire the characteristics of invasive mesenchymal cells. EMT has been implicated in cancer progression and metastasis as well as the formation of many tissues and organs during development. Epithelial cells undergoing EMT lose cell-cell adhesion structures and polarity, and rearrange their cytoskeletons. Several oncogenic pathways such as transforming growth factor (TGF)-$\beta$, Wnt, and Notch signaling pathways, have been shown to induce EMT. These pathways have activated transcription factors including Snail, Slug, and the ZEB family which work as transcriptional repressors of E-cadherin, thereby making epithelial cells motile and resistant to apoptosis. Mounting evidence shows that EMT is associated with cell invasion and tumor progression. In this review, we summarize the characteristic features of EMT, pathways leading to EMT, and the role of EMT in cell invasion. Three topics are addressed in this review: (1) Definition of EMT, (2) Signaling pathways leading to EMT, (3) Role of EMT in cell invasion. Understanding the role of EMT in cell invasion will provide valuable information for establishing strategies to develop anti-metastatic therapeutics which modulate malignant cellular processes mediated by EMT.

• 한국응급구조학회지
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• 제4권1호
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• pp.31-34
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• 2000

The real Emergency Medical Service (EMS) was introduced into Korea in the 1990s, but the role of the EMT in hospital has not been establish. This report is based on our experience for the purpose of introducing the role of the EMT in hospital. 1) EMT assisted a doctor in emergency department. 2) EMT served as a member of CPCR team in hospital during last 3 years. The survival rate of CPCR in hospital was higher than other result in Korea. 3) EMT performed his duties as a keeper of hemodynamically unstable or severely injured patients very well. 4) EMT transferred patients with safety. 5) EMT ran with rapid triage. We think that EMT will play an important role in hospital from now on.

• 생명과학회지
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• 제23권8호
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• pp.970-977
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• 2013

Epithelial-to-mesenchymal transition (EMT)는 embryogenesis에서 중요한 역할을 하며 tumor metastasis, invasion에도 관여함으로써 tumor progression 및 aggressiveness에 기여한다. EMT는 EMT hallmark인 epithelial E-cadherin의 발현 감소와 mesenchymal-like cell morphology를 획득함으로써 epithelial cell polarity를 잃어버리는 특징을 가지고 있다. $O_2{^-}$, $H_2O_2$, $OH^-$와 같은 활성산소가 EMT를 유도하는 것으로 알려져 있다. Snail이 E-cadherin의 발현을 억제함으로써 ROS에 의한 EMT에 관여하는 것으로 알려져 있으나, 그 기작은 완전히 밝혀져 있지 않다. 본 연구에서는, noninvasive breast tumor cell line인 MCF-7 세포에 Egr-1을 과발현시킨 후 그 영향을 조사하였다. Egr-1이 과발현되면, MCF-7 세포는 epithelial cell polarity를 잃고 spindle-shaped로 변화되므로, Egr-1이 EMT를 유도할 가능성이 대두되었다. 또한 Snail이 Egr-1에 의한 EMT에 관여함을 확인하였다. 나아가, 본 연구진은 Egr-1-Snail axis가 ROS에 의해 활성화 되고, ROS에 의한 EMT에서 중요한 역할을 함을 발견하였다.

• 동의생리병리학회지
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• 제34권2호
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• pp.61-66
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• 2020

Epithelial-mesenchymal transition (EMT) is the process by which epithelial cells lose their characters and acquire the properties of mesenchymal cells. EMT has been reported to exert an essential role in embryonic development. Recently, EMT has emerged as a pivotal mechanism in the metastasis of cancer and the fibrosis of chronic diseases. In particular, EMT is drawing attention as a mechanism of renal fibrosis in chronic kidney diseases such as diabetic nephropathy. In this study, we developed an EMT model by treating TGF-β1 on the podocytes, which play a key role in the renal glomerular filtration. This study explored the effects of Hwanggeum-tang (HGT) recorded in Dongeuibogam as being able to be used for the treatment of Sogal whose concept had been applied to Diabetes Mellitus (DM), on the TGF-β1-induced podocyte EMT. HGT suppressed the expression of vimentin and α-SMA, the EMT marker, in the human podocytes stimulated by TGF-β1. However, HGT increased the expression of ZO-1 and nephrin. Interestingly, HGT selectively inhibited the mTOR pathway rather than the classical Smad pathway. HGT also activated the AMPK signaling. HGT's inhibitory effect on the podocyte EMT through regulation of the mTOR pathway was achieved through the activation of AMPK, which was confirmed by comparison with cells treated with compound C (CC), an inhibitor of AMPK signaling. In conclusion, HGT can be applied to the renal fibrosis by preventing TGF-β1-induced EMT of podocytes through AMPK activation and mTOR inhibition.

• BMB Reports
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• 제55권8호
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• pp.370-379
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• 2022

Human pregnancy is a delicate and complex process where multiorgan interactions between two independent systems, the mother, and her fetus, maintain pregnancy. Intercellular interactions that can define homeostasis at the various cellular level between the two systems allow uninterrupted fetal growth and development until delivery. Interactions are needed for tissue remodeling during pregnancy at both fetal and maternal tissue layers. One of the mechanisms that help tissue remodeling is via cellular transitions where epithelial cells undergo a cyclic transition from epithelial to mesenchymal (EMT) and back from mesenchymal to epithelial (MET). Two major pregnancy-associated tissue systems that use EMT, and MET are the fetal membrane (amniochorion) amnion epithelial layer and cervical epithelial cells and will be reviewed here. EMT is often associated with localized inflammation, and it is a well-balanced process to facilitate tissue remodeling. Cyclic transition processes are important because a terminal state or the static state of EMT can cause accumulation of proinflammatory mesenchymal cells in the matrix regions of these tissues and increase localized inflammation that can cause tissue damage. Interactions that determine homeostasis are often controlled by both endocrine and paracrine mediators. Pregnancy maintenance hormone progesterone and its receptors are critical for maintaining the balance between EMT and MET. Increased intrauterine oxidative stress at term can force a static (terminal) EMT and increase inflammation that are physiologic processes that destabilize homeostasis that maintain pregnancy to promote labor and delivery of the fetus. However, conditions that can produce an untimely increase in EMT and inflammation can be pathologic. These tissue damages are often associated with adverse pregnancy complications such as preterm prelabor rupture of the membranes (pPROM) and spontaneous preterm birth (PTB). Therefore, an understanding of the biomolecular processes that maintain cyclic EMT-MET is critical to reducing the risk of pPROM and PTB. Extracellular vesicles (exosomes of 40-160 nm) that can carry various cargo are involved in cellular transitions as paracrine mediators. Exosomes can carry a variety of biomolecules as cargo. Studies specifically using exosomes from cells undergone EMT can carry a pro-inflammatory cargo and in a paracrine fashion can modify the neighboring tissue environment to cause enhancement of uterine inflammation.

• 한국응급구조학회지
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• 제10권2호
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• pp.35-42
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• 2006

Purpose: We studied that EMT took care in prehospital care of cardiac arrest patients by "the chain of survial", we need the data about treatment of EMT in prehospital care of cardiac arrest patients. and then we want to educate EMT for their emergency skill and knowledge of prehospital care of cardiac arrest patients. Method: We studied 162 cardiac arrest patients were transported by EMT in Jecheon province, Chingbuk. Results: 1. Stage of Early Access 96.9% of people who related the cardiac arrest patients used the Jecheon 119 Rescue at their emergency situation. 2 Stage of Early CPR The EMT supported keeping of airway to 148 of 162 cardiac arrest patients. Artificial respiration was 120 of 162 cardiac arrest patients and chest compression was 119 of 162 cardiac arrest patients. 3. Stage of Early AED There were shocked 6 cardiac arrest patients but weren't shocked 156 victims of 162 cardiac arrest patients by AED. 4. Stage of Early ACLS There were reported 3 of 162 cardiac arrest patients. to Doctor or Hospital Emergency Center for medical direction to EMT in prehospital area. There is no advanced airway, IV insertion and medication to the prehospital cardiac arrest patients.

• 한국컴퓨터정보학회논문지
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• 제23권10호
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• pp.151-156
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• 2018

The purpose of this study was to find more effective method through comparison of manual chest compression and chest compression using $AutoPulse^{TM}$ device in pre-hospital simulation cardiac arrest. In order to achieve the purpose of the study, ambulance workers did two different style CPR in pre-hospital simulation cardiac arrest. Data analyzed by T test and ANOVA. Findings of this study are as follows. Firstly, manual chest compression is more effective than chest compression using $AutoPulse^{TM}$ device on scene. Secondly, chest compression using $AutoPulse^{TM}$ device is more effective manual chest compression in ambulance and in elevator. In conclusion, these findings provide strong evidence for the importance of hands off time and stable CPR before hospital arrival in explaining patient's prognosis. Therefore, strategies to conduct precise hands off time and stable CPR are needed to improve patient's prognosis.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2006년도 추계학술대회
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• pp.43-50
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• 2006

본 연구에서는 미 운송부 산하 고속도로교통안전국에서 규정한 EMT-I 의 미 국립표준교과과정을 알아본 뒤, 기존 피츠버그 의과대학 응급의료센터에서 제공되는 교육과정의 구성과 내용에 대하여 소개하고 미 국립 응급구조사 협회의 연차보고서를 토대로 EMT-I 자격의 미국 내 시행실태를 파악하였다 또한. 각 주별로 제공되는 교육과정의 내용과 EMT-I 구급대원의 활동범위에 대하여는 응급 의료시스템 잡지의 주 별 현황조사를 실시하였다. 끝으로 장기적인 추진과제인 Paramedic 과정 개설에 관하여 제언하였다.

• Journal of Preventive Medicine and Public Health
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• 제30권2호
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• pp.369-380
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• 1997

Balb/c 마우스의 복강대식세포와 동종 마우스의 유선암에서 기원한 EMT-6 세포를 배양하는 조건에 여러 농도의 수은을 첨가하여 nitrite와 nitrite 생성의 변화를 관찰한 결과는 다음과 같다. 복강대식세포 및 EMT-6 세포가 생성하는 nitrite와 nitrate 양은 공히 배양시작 12시간 후에 생성량에 비해 24 시간 후에는 2배, 36시간 후에는 3배의 농도로 측정되었다. 이때 nitrite와 nitrate 농도 사이에 매우 밀접한 상관관계가 관찰되었다. 수음첨가에 따라 nitrite 및 nitrate 생성량은 용량 의존적 관계로 현저한 감소를 보이며, 24 시간 또는 36시간 후의 세포생존률도 역시 수은농도에 비례하여 감소되는데, 복강대식세포의 생존률 감소가 EMT-6 세포의 것에 비해 더욱 현저하였다. 이들 세포내에서 생성되는 ATP의 양은 복강세포의 경우 그 생존률과 비례하는 경향이었으나, EMT-6세포의 경우는 비교적 높은 생존률에도 불구하교 배양액내에 수은농도를 증가시킴에 따라 ATP생산은 현저히 감소하였다. 이상의 결과는 면역세포인 복강대식세포 뿐아니라 암세포인 EMT-6 세포에서도, L-arginine으로부터 nitric oxide를 생성하는 생화학적 반응이 수은에 의해 공히 억제될 수 있음을 보여준다. 한편 수은의 세포성 면역에 미치는 독성은 수은이 면역세포의 ATP생성과 관련한 에너지 대사과정의 장애을 초래하여 nitric oxide 생성에 필요한 반응에너지의 공급을 억제시키기 때문에 나타나는 현상으로 사료된다.

• 한국식품과학회지
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• 제50권1호
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• pp.105-110
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• 2018

멜리틴은 봉독의 주요 성분 중 하나로 항염증과 항암활성 효과를 가지고 있다. 우리는 폐암세포에서 멜리틴이 EMT 억제를 통해 암세포 이동과 침투를 억제하는 사실을 확인하였다. 멜리틴은 EGF로 유도된 폐암 세포 이동과 침투를 억제하였을 뿐만 아니라 EMT와 관련된 단백질인 이카드헤린의 발현을 증가시켰으며, 바이멘틴과 피브로넥틴 발현은 감소시켰다. 또한 멜리틴에 의한 EMT조절 전사인자인 ZEB2, Slug, Snail의 발현을 확인한 결과 멜리틴 처리에 의해 농도의존적으로 발현이 감소하였다. 또한 작용 메커니즘을 확인하기 위해 mTOR와 FAK 메커니즘을 확인한 실험에서 EGF 처리에 의해 증가한 AKT, mTOR, p70S6K, 4EBP1의 인산화가 멜리틴 농도의존적으로 감소하였다. 그러나 FAK는 EGF에 의해 변화가 없었으며, EKR, JNK 메커니즘은 EGF 처리에 의해 인산화가 증가하였으나 멜리틴 처리에 의해 아무런 영향을 받지 않았다. 그러므로, 폐암세포의 세포 이동과 침투에 대한 멜리틴의 억제효과는 AKT/mTOR/P70S6K/4EBP1 기전 억제를 통해 EMT를 억제하여 세포 이동과 침투를 억제하는 것으로 보인다.