• Molecules and Cells
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• v.20 no.2
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• pp.263-270
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• 2005

Transactivation of EGF-receptor (EGFR) by G-protein coupled receptors (GPCRs) is emerging as an important pathway in cell proliferation, which plays a crucial role in the development of atherosclerotic lesion. Angiotensin II (Ang II) has been identified to have a major role in the formation of atherosclerotic lesions, although the underlying mechanisms remain largely unclear. We hypothesize that Ang II promotes the proliferation and migration of smooth muscle cells through the release of heparin-binding epidermal growth factor like growth factor (HB-EGF), transactivation of EGFR and activation of Akt and Erk 1/2, with matrix metalloproteases (MMPs) playing a dispensable role. Primary rat aortic smooth muscle cells were used in this study. Smooth muscle cells rendered quiescent by serum deprivation for 12 h were treated with Ang II (100 nM) in the presence of either GM6001 ($20{\mu}M$), a specific inhibitor of MMPs or AG1478 ($10{\mu}M$), an inhibitor of EGFR. The levels of phosphorylation of EGFR, Akt and Erk 1/2 were assessed in the cell lysates. Inhibition of MMPs by GM6001 significantly attenuated Ang II-stimulated phosphorylation of EGFR, suggesting that MMPs may be involved in the transactivation of EGFR by Ang II receptor. Furthermore Ang II-stimulated proliferation and migration of smooth muscle cells were significantly blunted by inhibiting MMPs and EGFR and applying HB-EGF neutralization antibody, indicating that MMPs, HB-EGF and EGFR activation is necessary for Ang-II stimulated migration and proliferation of smooth muscle cells. Our results suggest that inhibition of MMPs may represent one of the strategies to counter the mitogenic and motogenic effects of Ang II on smooth muscle cells and thereby prevent the formation and development of atherosclerotic lesions.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.42
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• pp.309-335
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• 2009

Over the last several years, regarding to the strategic items, the international community has seen governments make more formal commitments to adopt and implement effective export controls to counter the proliferation of weapons of mass destruction(WMD). United Nations Security Council Resolution 1540(that is "S/RES/1540") stands as the most important of these commitments. Many UN members already have export control laws and regulations in place to prevent the proliferation of weapons of mass destruction. Many members also participate in a variety of formal and informal international arrangements to coordinate their export control efforts. Nonetheless, each of these countries has its own unique legal framework for export controls. This generates considerable diversity in the construction of the specific national legal authorities. Over the last few years, however, a consensus over what constitutes the key elements of effective legal authorities for export controls has begun to emerge. Evidence for this development comes in the identification of best legal authorities or principles at several multilateral conferences on export controls.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.683-688
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• 2003

Caffeine (1,3,7-trimethylxanthine), a central nervous system stimulant, is contained in various foods, beverages and over-the-counter medications. Sulfadimethoxine (SDM) is one of the anti-thyroid agents and induces proliferation of thyroid capsule in two stage thyroid carcinogenesis model using N-bis(2-hydroxypropyl)nitrosamine (DHPN). In this study, we examined the effect of caffeine on fibrous proliferation of thyroid capsule in DHPN and SDM-treated rats. Five-week-old male F344 rats were given a single subcutaneous injection of DHPN (2,800 mg/kg, body weight). Starting one week thereafter, SDM (1,000 ppm in drinking water) with or without caffeine (1,500 ppm in diet) was administered for 12 weeks. All animals were autopsied and histopathological examination of the thyroid glands was performed. Thyroid follicular proliferative changes were induced in all rats treated with DHPN+SDM. In addition, the proliferation of perithyroidal fibrous tissue and pleomorphic thyroid follicular cells within the capsule were observed in DHPN+SDM treated group. Caffeine would not be related to these lesions in this experimental condition. although pentoxifylline, a methyl xanthine derivative, has an anti fibrotic effects.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.39-52
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• 2000

Polypeptide growth factor belong to a class of potent biologic mediator which regulate cell differentiation, proliferation, migration and metabolism. 1,25-dihydroxyvitamin $D_3$ decrease cell proliferation, and stimulate alkaline phosphatase activity which express in osteoblast during cell differentiation period. IGF-I is known to stimulate cell proliferation and differentiation too. 1,25-dihydroxyvitamin $D_3$ is known to increase IGF-I binding sites and IGF binding protein which inhibite the effect of IGF. The purpose of this study is to evaluate potential role of IGF-I as mediator that control the action of 1,25-dihydroxyvitamin $D_3$. MC3T3-E1 cell were seeded $5{\times}10^5/ml$ at 100mm culture plate in ${\alpha}-MEM$ containing 10% fetal bovine serum. After 48 hour incubation period, medium were changed ${\alpha}-MEM$ containing 5% fetal bovine serum. After 24 hours, $10^{-9}M$ 1,25-dihydroxyvitamin $D_3$ added. Total mRNA was extracted at 0, 6, 24, 48, 72 hour. PRPCR method was programed for the detection of IGF-I mRNA. In the both groups of 1,25-dihydroxy vitamin $D_3$ treated and control, alternative splicing form of IGF-I, IGF-IA and IGF-IB were expressed. In the 1,25-dihydroxyvitamin $D_3$ treated group, IGF-I mRNA expression was matained until 24 hour, there after expression was decresed. MC3T3-E1 cell were seeded $2.5{\times}10^4/ml$ at 24well plate in ${\alpha}-MEM$ containing 10% fetal bovine serum. After 48 hour incubation period, medium were changed ${\alpha}-MEM$ containing 3% fetal bovine serum. After 24 hours, $10^{-9}M$ 1,25-dihydroxyvitamin $D_3$ and 10 ng/ml IGF-I were added separately or together. Cell were cultured for 1 and 3 days, $2{\mu}Ci/ml\;[^3H]$ -thymidine was added for the last 24h of culture of each days. ${[^3H]}$-thymidine incorporation in to DNA was measured and expressed counter per minute(CPM). DNA synthetic activity was significantly decreased by 1,25-dihydroxyvitamin $D_3$ both at 1 day and 3 day, and in the combination group of 1,25-dihydroxyvitamin $D_3$ and IGF-I, DNA synthetic activity was also decreased both at 1 day and 3 days. IGF-I did not affect the DNA synthetic activity compared to control group both at 1 day and 3 day. From the above results, 1,25-dihydroxyvitamin $D_3$ was potent inhibitor of cell proliferaton in MC3T3-E1 cells. It assumed that the effect of 1,25-dihydroxyvitamin $D_3$ on osteoblast proliferation may be mediated in part by decreased level of IGF-I.

• The Journal of Korean Medicine
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• v.25 no.2
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• pp.51-66
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• 2004

Objectives : To evaluate experimentally the clinical effect of Bojeongjeongcheon-tang, we observed the cytokines ($IL-1{\beta}$/TEX>, IL-4, IL-5, IL-6, IL-10, TNF-{\alpha},{\;}TGF-{\beta},{\;}IFN-{\gamma}$) and what effect they have on IgE in B cells of a rat. Methods : First of all, we extracted the spleens of healthy Balb/c mice and separated B cells from them. These B cells were cultured with anti-CD40 mAb (500 ng/ml), rmIL-4 (500 U/ml), Bojeongjeongcheon-tang (100 ug/ml, 10 ug/ml, 1 ug/ml). We used rmiL-10 (50 ng/ml) as a control group. Furthermore, we analyzed the expression of IgE, CD23, CD69 and the coherence of HRF in B cells using a flow cytometer. We also analyzed the cytokine gene expression in B cells by reverse transcriptase-PCR. We also measured B cells proliferation using the Liquid Scintillation Counter. Results : In this study, the Bojeongjeongcheon-tang treated group showed a tendency to decrease depending on the density compared with the control group in the expression of IgE+, CD23+, CD69, HRF. All of the Bojeongjeongcheon-tang treated group showed inhibitory effects with $IL-1{\beta}$, IL-4, IL-5 and proliferating effects with IL-6, IL-10, and $IFN-{\gamma}$ on cytokines transcript expression depending on the density. Meanwhile, $TNF-{\alpha}$ increased in all density. In IgE production, there was inhibitory effect on Bojeongjeongcheon-tang (both 100 ug/ml and 10 ug/ml) of significance (p < 0.01, p < 0.05). Also in B cell proliferation, the result revealed an inhibitory effect of Bojeongjeongcheon-tang (both 100 ug/ml and 10 ug/ml), of significance (p < 0.001, p < 0.01). Conclusions : This study shows that Bojeongjeongcheon-tang has an inhibitory effect on the production and activity of B cells. Also it inhibited CD23, IL-4 activity and IgE production and activation. It is obvious that Bojeongjeongcheon-tang treats asthma by inhibiting the production of histamine and HRF, IL-5 and proliferating IL-10. Also Bojeongjeongcheon-tang has some preventive effects on bronchial change by inhibiting $TGF-{\beta}$, which stimulates the bronchial transformation.

• The Journal of Internal Korean Medicine
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• v.36 no.1
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• pp.1-12
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• 2015

Objectives : This study was performed to investigate the anti-cancer effects of Rhus verniciflua Stokes (RVS) extracted with sterile distilled water on cholangiocarcinoma cell lines. Materials and Methods : Two cholangiocarcinoma cell lines, SNU-1079 and SNU-1196, were used in this study. Cells were treated with different concentrations of RVS for 24, 48, and 72 hours. Cell count, viability, apoptosis, and mRNA expression of Bax, Bcl-2, Mcl-1, survivin, caspase-3, and cyclin D1 and P21 were determined with an automatic cell counter (ADAM-MC), MTT assay, apoptosis assay (Annexin-V/PI staining), and RT-PCR. Results : All cells treated with RVS showed decreased cell counts in a dose-dependent manner. RVS inhibited proliferation of SNU-1196 in a dose-dependent manner, but SNU-1079 proliferation was inhibited in the long-time culture group in a dose-dependent manner. The proportion of early and late-stage apoptotic cells was increased by RVS in a dose-dependent manner in SNU-1196. In contrast, it was increased significantly in SNU-1079 treated with high-dose RVS. After treatment with RVS, the mRNA expression of Bcl-2 was decreased while Bax was increased in SNU-1079. Cyclin D1 mRNA levels were decreased in SNU-1196 in a dose-dependent manner. P21 expression was increased in all cells after the treatment with RVS. Conclusions : RVS appears to have potential as a therapeutic agent for cholangiocarcinoma.

• Journal of Contemporary Eastern Asia
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• v.21 no.1
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• pp.53-71
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• 2022

The overall purposes of this study are to identify actions taken to counter predatory publishing practices as well as to propose an ICT-based model to detect such practices. The need to raise quantitative performance metrics to support career goals has created immense pressure on researchers to publish in the literature as frequently as possible. This "publish or perish" syndrome appears to be fueling a rise in scholarly journals and conferences that provide quicker and easier routes to publication. However, such avenues sometimes involve questionable academic practices with important ethical ramifications. One notable example is the proliferation of predatory publishing, including predatory journals and fake conferences. The widening impact of such activities is beginning to prompt academic societies, publishers, and institutions to take measures. This paper discusses the issues on predatory publishing practices, and some of the actions taken by various stakeholders to address these practices. In order to build a transparent and sustainable scholarly publishing ecosystem, this study highlights multi-dimensional and specific solutions, including reforms to research ethics codes, research management rules, and legal protection from exploitative practices. This paper proposes an ICT-based cooperative model for monitoring of predatory publishers as a potential solution to create a sustainable and transparent infrastructure for a scholarly publication system guarding against misconduct in publishing practices.

• Journal of Microbiology and Biotechnology
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• v.32 no.11
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• pp.1447-1453
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• 2022

Prohibitin 1 (Phb1) is a pleiotropic protein, located mainly in the mitochondrial inner membrane and involved in the regulation of cell proliferation and the stabilization of mitochondrial protein. Acetaminophen (APAP) is one of the most commonly used over-the-counter analgesics worldwide. However, at high dose, the accumulation of N-acetyl-p-benzoquinone imine (NAPQI) can lead to APAP-induced hepatotoxicity. In this study, we sought to understand the regulation of mRNA expression in relation to APAP and GSH metabolism by Phb1 in normal mouse AML12 hepatocytes. We used two different Phb1 silencing levels: high-efficiency (HE, >90%) and low-efficiency (LE, 50-60%). In addition, the siRNA-transfected cells were further pretreated with 0.5 mM of Sadenosylmethionine (SAMe) for 24 h before treatment with APAP at different doses (1-2 mM) for 24 h. The expression of APAP metabolism-related and antioxidant genes such as Cyp2e1 and Ugt1a1 were increased during SAMe pretreatment. Moreover, SAMe increased intracellular GSH concentration and it was maintained after APAP treatment. To sum up, Phb1 silencing and APAP treatment impaired the metabolism of APAP in hepatocytes, and SAMe exerted a protective effect against hepatotoxicity by upregulating antioxidant genes.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.2
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• pp.219-246
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• 2017

Nuclear issue is a good example showing globalization of the international regime. The history showed nuclear weapons may cause the extinction of human races when the first nuclear bombs fell down to Japan in August, 1945 and people became increasingly eager to achieve peace. Military buildup for national security is a matter of existence in the international society. However, disarmament or arms control to secure international peace and safety which is also the purpose of the Charter of the United Nations may be the most important task for us to realize peace of the mankind. Today, disarmament, together with amicable settlement of international conflicts and collective security system, is an important means to maintain and promote international peace and safety. It might be our permanent task to realize complete disarmament but, as the Preamble of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) expressed general and complete disarmament, the international society has clarified its effort for complete disarmament. Thus, taking a look into the international regime on the nuclear issue and progress related to the nuclear issue in North Korea, the study was intended to introduce the globalization of the nuclear issue, review the international effort for nuclear disarmament based on the concept of the 'common heritage of the mankind' and with respect to the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and controls over nuclear weapons, and then evaluate the North Korean nuclear issue, which is in direct relation with South Korea and international laws, in terms of the space law and disarmament acts. The collective security system along with policies to prevent dissemination of nuclear weapons should also be emphasized and implemented to cope with the North Korean nuclear issue.