• BMB Reports
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• v.29 no.2
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• pp.175-179
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• 1996

Viral surface proteins are known to play an essential role in attachment of the virus particle to the host cell membrane. In case of the hepatitis B virus (HBV) several reports have described potential receptors on the target cell side, but no definite receptor protein has been isolated yet. As for the viral side, it has been suggested that the preS region of the envelope protein, especially the preS1 region, is involved in binding of HBV to the host cell. In this study, preS1 region was recombinantly expressed in the form of a maltose binding protein (MBP) fusion protein and used to identify and visualize the expression of putative HBV receptor(s) on the host cell. Using laser scanned confocal microscopy and by FACS analysis, MBP-preS1 proteins were shown to bind to the human hepatoma cell line HepG2 in a receptor-ligand specific manner. The binding kinetic of MBP-preS1 to its cellular receptor was shown to be temperature and time dependent. In cells permeabilized with Triton X-100 and treated with the fusion protein, a specific staining of the nuclear membrane could be observed. To determine the precise location of the receptor binding site within the preS1 region, several short overlapping peptides from this region were synthesized and used in a competition assay. In this way the receptor binding epitope in preS1 was revealed to be amino acid residues 27 to 51, which is in agreement with previous reports. These results confirm the significance of the preS1 region in virus attachment in general, and suggest an internalization pathway mediated by direct attachment of the viral particle to the target cell membrane.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.552-557
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• 2009

Objective : Interferon-$\beta$, (IFN-$\beta$) has been used in the treatment of cancers. Inhibition of the enzyme cyclooxygenase (COX) with celecoxib had a significantly suppressive effect on tumor growth, angiogenesis, and metastasis in a variety of tumors. The aim of this study was to elucidate the antiglioma effect of combined treatment with IFN-$\beta$ and celecoxib in U87 glioma model. Methods : The in vitro effects of IFN-$\beta$ (50-1,000 IU/mL) and celecoxib ($50-250\;{\mu}M$) alone or combination of both on the proliferation and apoptosis of U87 cells were tested using MTT assay, FACS analysis and DNA condensation. To determine the in vivo effect, nude mice bearing intracerebral U87 xenograft inoculation were treated with IFN-$\beta$ intraperitoneally ($2{\times}10^5\;IU/day$ for 15 days), celecoxib orally (5, 10 mg/kg) or their combination. Results : IFN-$\beta$ or celecoxib showed an inhibitory effect on the proliferation of U87 cells. When U87 cells were treated with IFN-$\beta$ and celecoxib combination, it seemed that IFN-$\beta$ interrupted the antiproliferative and apoptotic activity of celecoxib. No additive effect was observed on the survival of the tumor bearing mice by the combination of IFN-$\beta$ and celecoxib. Conclusion : These results suggest that IFN-$\beta$ seems to inhibit the antiglioma effect of celecoxib, therefore combination of IFN-$\beta$ and celecoxib may be undesirable in the treatment of glioma.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.764-770
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• 2013

Stevia rebaudiana is a traditional herb used as a sweetener in Brazil and Paraguay as well as Korea and China. This study investigated the efficacy of Stevia rebaudiana methanol extract (SRE) to protect cells against the mitochondrial dysfunction and apoptosis in hepatocyte. To determine the effects of SRE on oxidative stress, we used the human derived hepatocyte cell line, HepG2 cell. Treatment of arachidonic acid (AA)+iron in HepG2 cells synergistically amplified cytotoxicity, as indicated by the excess reactive oxygen species (ROS) and mitochondrial permeability transition by fluorescence activated cell sorter (FACS) and immunoblot analysis. Treatment with SRE protected hepatocytes from AA+iron-induced cellular toxicity, as shown by alterations in the protein levels related with cell viability such as procaspase-3. SRE also prevented the mitochondrial dysfunction induced by AA+iron, and showed anti-oxidant effects as inhibition of $H_2O_2$ production and GSH depletion. Moreover, we measured the effects of SRE on AMP-activated protein kinase (AMPK), a key regulator in determining cell survival or death. Acetyl-CoA Carboxylase (ACC), a direct downstream target of AMPK. SRE increased phosphorylation of ACC, and prevented the inhibition of ACC phosphorylation by AA+iron. These results indicated that SRE has the ability to protect cells against AA+iron-induced $H_2O_2$ production and mitochondrial impairment, which may be mediated with AMPK-ACC pathway.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.349-360
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• 2011

The objectives of present study were to characterize the peptides which were isolated from Korean fermented soybean paste, chungkukjang, and to determine their antioxidant activities. Four fractions were collected from the methanol extract of chungkukjang by using a recycling preparative HPLC. Among fractions, Fr-2 was identified to be highly potent free radical scavenging activity in the assay of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and nitroblue tetrazolium(NBT)-reduction inhibition. Base on antioxidant effects, fraction Fr-2 was employed for the refraction with a prep-column and separated into five fractions of which two fractions were identified to have higher antioxidant activity. To confirm the amino acid constituents of antioxidant fractions Fr-2-2 and Fr-2-3 were analyzed, and eight kinds of amino acids such as aspartic acid, threonine, serine, glutamic acid, glycine, lysine, histidine, and arginine were identified as the constituent amino acids. Antioxidant activities of the separated peptides were further assessed cell viability with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl terazolium bromide (MTT), and fluorescence-activated cell sorting (FACS) analysis of H4IIE cells treated with hydrogen peroxide (H2O2). Chungkukjang peptides have shown their ability to protect H4IIE rat hepatoma cells against H2O2- induced oxidative stress by concentration and time-dependent manner. Therefore, These results indicated that fermented soybean paste chungkukjang will be promoted the antioxidant and radical scavenging activities, and beneficial for health. The antioxidant peptide fractions Fr-2-2 and Fr-2-3 were denominated as P-NICS-1 and P-NICS-2, respectively. However, further studies were required to clarify their amino acid sequences and molecular properties, and physiological significances.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.616-623
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• 2017

Ginsenoside Rg3, a saponin extracted from ginseng, has various pharmacological and biological activities; however, its effects against Brucella infection are still unclear. Herein, the inhibitory effects of ginsenoside Rg3 against intracellular parasitic Brucella infection were evaluated through bacterial infection, adherence assays, and LAMP-1 colocalization, as well as immunoblotting and FACS for detecting MAPK signaling proteins and F-actin polymerization, respectively. The internalization, intracellular growth, and adherence of Brucella abortus in Rg3-treated RAW 264.7 cells were significantly decreased compared with the Rg3-untreated control. Furthermore, an apparent reduction of F-actin content and intensity of F-actin fluorescence in Rg3-treated cells was observed compared with B. abortus-infected cells without treatment by flow cytometry analysis and confocal microscopy, respectively. In addition, treating cells with Rg3 decreased the phosphorylation of MAPK signaling proteins such as ERK 1/2 and p38 compared with untreated cells. Moreover, the colocalization of B. abortus-containing phagosomes with LAMP-1 was markedly increased in Rg3-treated cells. These findings suggest that ginsenoside Rg3 inhibits B. abortus infection in mammalian cells and can be used as an alternative approach in the treatment of brucellosis.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.383-391
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• 2008

The glycans linked to the insect cell-derived glycoproteins are known to differ from those expressed in mammalian cells, partly because of the low level or lack of glycosyltransferase activities. GnT II, GnT IV, GnT V, and ST3Gal IV, which play important roles in the synthesis of tetraantennarytype complex glycan structures in mammalian cells, were overexpressed in Trichoplusia ni cells by using a baculovirus expression vector. The glycosyltransferases, expressed as a fusion form with the IgG-binding domain, were secreted into the culture media and purified using IgG sepharose resin. The enzyme assay, performed using a pyridylaminated-sugar chain as an acceptor, indicated that the purified glycosyltransferases retained their enzyme activities. Human erythropoietin expressed in T. ni cells (rhEPO) was subjected to in vitro glycosylation by using recombinant glycosyltransferases and was converted into complex-type glycan with terminal sialic acid. The presence of Nacetylglucosamine, galactose, and sialic acid on the rhEPO moiety was detected by a lectin blot analysis, and the addition of galactose and sialic acid to rhEPO was confirmed by autoradiography using $UDP-^{14}C-Gal\;and\;CMP-^{14}C-Sia$ as donors. The in vitro glycosylated rhEPO was injected into mice, and the number of reticulocytes among the ed blood cells was counted using FACS. A significant increase in the number of reticulocytes was not observed in the mice injected with in vitro glycosylated rhEPO as compared with those injected with rhEPO.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.24 no.3
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• pp.151-156
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• 2013

Objectives : It has been reported that higher percentage of B cells react with monoclonal D8/17 antibody in patients with rheumatic fever, childhood onset obsessive-compulsive disorder, Tourette's disorder, or prepubertal anorexia nervosa. The purpose of this study is to replicate the previous studies in a Korean young population with tic disorder and to identify any relationship between D8/17 and clinical symptoms. Methods : The binding of D8/17 to B cells was determined in patients with tic disorder (N=21) and healthy controls (N=9) by Fluorescence-Activated Cell Sorter analysis. Results : In the sample examined by this study, the average percentage of B cells expressing D8/17 in tic disorder was 2.05%; healthy controls was 3.15%. No statistically significant differences were found in the mean percentages of D8/17 between the two groups. Conclusion : The expression of D8/17 in B cells was very low in this study. No subjects with tic disorder or healthy controls was above 12% in D8/17 positive proportion. Further studies, including higher number of patients and control group members, should be performed.

• The Journal of Internal Korean Medicine
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• v.25 no.3
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• pp.451-460
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• 2004

Objective : 황금의 유방암세포주에 대한 항암효과 및 기전에 대한 연구는 아직 미흡하며, 특히 에스트로젠리셉터를 가지지않은 유방암세포주인 MDA-MB-231에 대한 효과 및 기전에 대한 연구는 아직 발표된바 없어, 이에 대한 연구가 진행되었다. Methods : 인간 유방암세포주 MDA-MB-231 MTT assay를 이용 성장방해비율을 조사하였으며. FACS analysis를 이용 cell cycle analysis를 시행하였고, Western Blot Analysis 및 Annexin V analysis를 시행하였다. Results : MDA-MB-231에 대한 황금의 IC50는 180 ug/ml 이었으며 최대 세포성장억제효과는 $500{\mu}g/ml$로 한약재중 비교적 강한 세포독성을 보여 주었다. 유세포분석 에서 황금 $500{\mu}g/ml$의 농도를 72시간 투여한 경우 세포사멸(Sub Gl) 분율이 대조군의 1.7%에 비해 21%로 높아 현저한 용량의존적인 세포사멸현상을 보여주었으며, 세포사멸을 보다 명확히 규명할 수 있는 Annexin V analysis에서도 황금 $200{\mu}g/ml$농도일때 48시간에서 17%의 뚜렷한 세포사멸효과를 나타내었다. 한편 세포사멸촉진인자인 Bax, 세포사멸실행단백질인자인 caspase 3의 활성과 PARP의 분할은 세포사멸이 세포주기정지와 더불어 세포사멸의 과정에 p53이 관여함을 알 수 있다. 앞으로의 연구는 p53발현이 다른 세포주와 각 단백질의 억제제를 통해 인과적인 관련성을 즘 더 명확히 할 필요가 있어야 할 것으로 생각되어진다. Conclusion : 유방암의 예후에 있어 호르몬치료에 부적절함으로 인해 예후가 나쁜 에스트로젠리셉터 발현이 없는 유방암에 대해서도 황금이 탁월한 항암효과를 보여주고 있으며, 임상적으로 황금단독, 다른 항암약재와의 배합, 그리고 기존의 항암화학요법이나 방사선요법과의 병용투여를 통한 초기 및 진행된 유방암의 치료에 대한 새로운 접근의 실마리를 제공할 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6463-6468
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• 2012

Purpose: To evaluated the effect of the gambogic acid (GA), one of the effective components of Garcinia, in combination with a new multi-targeted oral medication, sunitinib (SU) on renal cancer cell proliferation in vitro and on tumor growth in vivo. Methods: After treatment with GA or SU, either alone or in combination, MTT and FACS analysis were used to examine cell viability and cycle distribution of the renal carcinoma cell lines 786-0 and Caki-1. Western blotting was employed to examine the expression of proteins related to the cell cycle and vascular formation. Furthermore, a xenograft model was applied to study the antitumor efficacy of SU or GA alone or in combination, with immunohistochemistry to detect expression of proteins related to xenograft growth and angiogenesis. Western blotting was used to examine NF-${\kappa}B$ signaling pathway elements in xenografts. Results: Treatment of 786-0 and Caki-1 cells with GA or SU resulted in decreased tumor cell proliferation, especially with joint use. Cells accumulated more strongly in the sub-G1 phase after joint treatment with GA and SU than treatment of GA and SU alone. Western blotting arrays showed 1 protein significantly upregulated, 2 proteins downregulated, and 2 proteins unchanged. Moreover, combined use of GA and SU inhibited the growth and angiogenesis of xenografts generated from Caki-1 significantly. Immunohistochemistry arrays showed downregulation of the expression of proteins promoting xenograft growth and angiogenesis, and Western blotting showed inhibition of the NF-${\kappa}B$ signaling pathway after treatment by GA alone and in combination with SU in xenografts. Conclusions: Our results show that the joint use of GA and SU can provide greater antitumor efficacy compared to either drug alone and thus may offer a new treatment strategy for renal cell carcinoma.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.2
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• pp.38-48
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• 2008

Purpose: This study was conducted to investigate the effects of Hominis Placenta (紫河車) on the growth of human uterine myoma cells and cell apoptosis. Methods: Human uterine leiomyoma cells were cultured and treated with Hominis Placenta extract for 48 hours. Cell proliferation and activity was analyzed by MTT assay. We analyzed the cell cycle of human uterine myoma cells treated Hominis Placenta extract by FACS. Expression of proteins related to cell apoptosis (Bax, Bcl-2), cyclin-D1 and VEGF were evaluated by Western blotting method. Results: The human uterine myoma cells treated by Hominis Placenta extract didn't proliferate below the concentration of $10mg/m{\ell}$. And there was no remarkable difference on cell cycle analysis below the concentration of $10mg/m{\ell}$. The expression of Bax was decreased and the expression of Bcl-2 was increased after the treatment of Hominis Placenta extract. But the expressions of cyclin-D1 and VEGF were increased after the treatment of Hominis Placenta extract. Conclusion: This study suggests that Hominis Placenta induce uterine myoma cell apoptosis and have effect on the myoma cell proliferation in the concentraion below $10mg/m{\ell}$.