• Toxicological Research
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• v.26 no.4
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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.

• The Korean Journal of Emergency Medical Services
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• v.4 no.1
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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.

• Journal of Life Science
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• v.23 no.8
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• pp.970-977
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• 2013

The epithelial-to-mesenchymal transition (EMT) plays an essential role in embryogenesis and is involved in tumor metastasis and invasion; it significantly contributes to tumor progression and aggressiveness. The EMT is characterized by a loss of epithelial cell polarity as a result of the reduced expression of epithelial E-cadherin, a hallmark of the EMT, and the acquisition of mesenchymal-like cell morphology. Reactive oxygen species (ROS) such as $O_2{^-}$, $H_2O_2$, and $OH^-$ have been demonstrated to induce the EMT; although Snail is involved in ROS-induced EMT by transcriptionally repressing E-cadherin, its mechanism is not fully understood. In this study, we examined the effects of early growth response 1 (Egr-1) overexpression in noninvasive breast tumor cell line MCF-7 cells. Upon Egr-1 overexpression, MCF-7 cells lost epithelial cell polarity and became more spindle-shaped, indicating that Egr-1 may induce EMT. We found that Snail is implicated in Egr-1 induced EMT. We further demonstrate that the Egr-1-Snail axis is activated by ROS and plays a critical role(s) in ROS-induced EMT.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.2
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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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• v.55 no.8
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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.

• The Korean Journal of Emergency Medical Services
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• v.10 no.2
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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.

• Journal of the Korea Society of Computer and Information
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• v.23 no.10
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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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• 2006.12a
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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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• v.30 no.2 s.57
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• pp.369-380
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• 1997

The effects of treatment with mercury chloride on the nitrite and nitrate syntheses were observed in peritoneal macrophages from Balb/c mice and EMT-6 cells in vitro. The cells were cultured in Dulbecco's modified Eagle's medium(DMEM) with cytokines. Amounts of nitrite and nitrate in the culture media after 24 and 36 hours of culture were about 2-fold, and 3-fold of those measured after 12 hours respectively. There were very close associations Between the amounts of nitrite and nitrate measured in the culture media according to culture time. The survival rate of peritoneal macrophages was significantly decreased by mercury chloride added into the media in dose-dependent manner, however the survivals of EMT-6 cells were not influenced by mercury chloride concentration in media. Nitrite and nitrate syntheses were dose-dependently decreased by mercury chloride added in culture media. ATP synthesis also decreased in EMT-6 cells by mercury chloride. These results reported here suggest that the disorder of cell mediated immunity by mercurials could be related to the inhibition of nitric oxide synthesis which seems to be caused by the inhibition of ATP synthesis.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.105-110
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• 2018

Melittin is the main component of apitoxin (bee venom) that has been reported to have anti-inflammatory and anti-cancer effects. Herein, we demonstrated that inhibition of epithelial-mesenchymal transition (EMT) by melittin causes suppression of cancer cell migration and invasion. Melittin significantly suppressed the epidermal growth factor (EGF)-induced cell migration and invasion in lung cancer cells. Moreover, melittin up-regulated the expression of epithelial marker protein, E-cadherin, and down-regulated the expression of EMT related proteins, vimentin and fibronectin. Mechanistic studies revealed that melittin markedly suppressed the expression of EMT mediated transcription factors, ZEB2, Slug, and Snail. The EGF-induced phosphorylation of AKT, mTOR, P70S6K, and 4EBP1 was also inhibited by melittin, but not that of ERK and JNK. Therefore, the inhibitory effect of melittin on migration and invasion of lung cancer cells may be associated with the inhibition of EMT via blocking of the AKT-mTOR-P70S6K-4EBP1 pathway.