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Busan, South Korea

Dongseo University is a major private university located in the port city of Busan, South Korea. It has approximately 12,000 undergraduate students and 500 graduate students, including 600 international students from 27 countries. It employs 350 full-time faculty members. The current president is Jekuk Chang . Wikipedia.

Lee J.,Dongseo University
Korean Journal of Physiology and Pharmacology | Year: 2013

Hepatocellular carcinoma (HCC) related to hepatitis B virus (HBV) and hepatitis C virus (HCV) infections is thought to account for more than 80% of primary liver cancers. Both HBV and HCV can establish chronic liver inflammatory infections, altering hepatocyte and liver physiology with potential liver disease progression and HCC development. Cyclophilin A (CypA) has been identified as an essential host factor for the HCV replication by physically interacting with the HCV non structural protein NS5A that in turn interacts with RNA-dependent RNA polymerase NS5B. CypA, a cytosolic binding protein of the immunosuppressive drug cyclosporine A, is overexpressed in many cancer types and often associated with malignant transformation. Therefore, CypA can be a good target for molecular cancer therapy. Because of antiviral activity, the CypA inhibitors have been tested for the treatment of chronic hepatitis C. Nonimmunosuppressive Cyp inhibitors such as NIM811, SCY-635, and Alisporivir have attracted more interests for appropriating CypA for antiviral chemotherapeutic target on HCV infection. This review describes CypA inhibitors as a potential HCC treatment tool that is contrived by their obstructing chronic HCV infection and summarizes roles of CypA in cancer development. Source

Lee J.,Dongseo University
Archives of Pharmacal Research | Year: 2010

Cyclophilins (Cyps) are ubiquitously expressed proteins that are evolutionarily conserved. CypA is the most abundant among the Cyps and is expressed in the cytosol. With its chaperone and PPIase activities, CypA contributes to the maintenance of correct conformation of nascent or denatured proteins and also provides protection against environmental insults. Also, its expression is induced in response to a wide variety of stressors including cancer. Upregulation of CypA in small cell lung cancer, pancreatic cancer, breast cancer, colorectal cancer, squamous cell carcinoma and melanoma has been reported. In some cancers a correlation between CypA overexpression and malignant transformation has been established. While molecular partners of CypA that promote cancer development are yet to be discovered, various mechanisms have been proposed to account for the cytoprotective functions of CypA during cancer development. CypA may promote the survival of cells under the stressful condition of cancer. CypA may well be essential for maintaining the conformation of oncogenic proteins, signalling proteins for cell proliferation, antiapoptotic components, transcription factors, or cell motility regulatory proteins. Antioxidant effects of CypA, which have been suggested by some researchers, may also become critical to reactive oxygen species (ROS) creating an oncogenetic environment. Developing new CypA inhibitors for therapeutics has been surmised from the cytoprotective functions of CypA and its overexpression in many cancer types. Therefore, CypA can be further investigated as a useful tool for early diagnosis, treatment and prevention of human cancers. © 2010 The Pharmaceutical Society of Korea and Springer Netherlands. Source

Shin H.J.,Dongseo University
Journal of Biotechnology | Year: 2010

NahR, a transcriptional regulator for naphthalene degradation in response to salicylate, is a central element in the microbial biosensor for detection of naphthalene and salicylate. To maximize the sensitivity of the biosensor, we have chosen a rational design of highly-sensitive microbial biosensors by introducing site directed mutagenesis to nahR gene. Eight single mutants (N169A, N169C, N169K, N169S, R248H, R248M, R248Q, and R248Y) were made at residues 169 and 248 known as the central inducer-recognition and the C-terminal multimerization domain. The effects of these mutations were examined by monitoring expression of a firefly luciferase (luc) reporter gene under the control of NahR. We found that all mutants at residues 248 and N169C show increased sensitivity (maximum ~50-fold) compared to wild type, respectively. R248M shows response even at toxic concentration, 5. mM. The results show the feasibility and potential versatility of mutational approach for the development of the highly-sensitive microbial biosensors. © 2010 Elsevier B.V. Source

Lee J.,Dongseo University
Archives of Pharmacal Research | Year: 2010

The fungal cyclic peptide cyclosporin A (CsA) and fungal macrolide compound sanglifehrin A (SFA) have been developed as immunosuppressive drugs and both bind to cyclophilin A (CypA). CypA has been reported to be upregulated in diverse human cancers including hepatocellular carcinomas (HCC). CypA overexpression induces resistance to hypoxia and chemotherapeutic agents such as cisplatin in cancer cells. In this report, it was shown that CsA or SFA can synergistically increase apoptotic cell death in HCC cells, when combined with cisplatin. The increased cytotoxicity was accompanied by enhanced oxidative stress. The effects of CsA and SFA were due to inhibition of CypA activity. It was also shown that CsA and SFA abrogate cisplatin resistance as well as protection against hypoxia that is provided by CypA overexpression. Importantly, the synergistic effect of CsA or SFA with cisplatin was shown even in p53 defective Hep3B cells. Finally, overexpression of CypA was observed in human HCC tissues. In conclusion, CsA or SFA synergistically enhances cisplatin-induced apoptosis in HCC cells including the p53-defective Hep3B. © 2010 The Pharmaceutical Society of Korea and Springer Netherlands. Source

Jang J.-Y.,Kwangwoon University | Shin D.,Dongseo University | Kim E.-S.,Kwangwoon University
Optics Express | Year: 2014

We propose a novel approach to optically refocus threedimensional (3-D) objects on their real depth from the captured elemental image array (EIA) by using a sifting property of the periodic d-function array (PDFA) in integral-imaging. By convolving the PDFAs whose spatial periods correspond to each object's depth with the sub-image array (SIA) transformed from the EIA, a set of spatially filtered-SIAs (SF-SIAs) for each object's depth can be extracted. These SF-SIAs are then inversetransformed into the corresponding versions of the EIAs, and from these, 3- D objects with their own perspectives can be reconstructed to be refocused on their depth in the space. The feasibility of the proposed method has been confirmed through optical experiments as well as ray-optical analysis. © 2014 Optical Society of America. Source

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