• Journal of Korea Foundry Society
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• v.16 no.6
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• pp.565-575
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• 1996

In this study, to gain the semi-solid alloy we employed the electromagnetic rotation by a induction motor of 3-phases and 2-poles for Al-7wt%Si alloy and observed the size of primary solid particle, distribution state of primary solid particle, the degree of sphericity, and fraction of primary solid for the evaluation of its results. The size of primary solid particle increases from $98{\mu}m$ to $118{\mu}m$ as solid fraction increases from 0.2 to 0.5. The degree of sphericity increased as the solid fraction increased. Solid particles obtained from the microstructures of isothermally held sample were coarsened and the degree of sphericity was enhanced as isothermal holding time increased. However, when the sample was stirred for more than 40min, solid particles merged together and liquid phase was entrapped within the cluster of solid particles. The size of primary solid particle was not changed significantly with the variation of input voltages by 160V over which solid particles began to merge together to be a large cluster of about $170{\mu}m$ at 180V. The standard deviation and the degree of sphericity were not changed significantly with the variation of input voltage.

• Journal of Photoscience
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• v.8 no.3_4
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• pp.105-112
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• 2001

Susceptibility to low temperature photoinhibition in photosynthetic apparatus was compared among three cucumber cultivars, Gahachungjang (GH), Banbaekjijeo (BB) and Gaeryangsymji (GR). By chilling in the light for 6 h, a sustained decrease in the potential quantum yield (Fv/Fm) and the oxidizable P700 contents was observed, and the decrease was less in GH than in BB and GR. Although the difference was small, some $\Phi_{PSII}$ remained in GH after light-chilling for 6 h indicating that a few electrons can flow around photosystem II(PSII). As a consequence, the primary electron acceptor of PSII, $Q_{A}$, was reduced slowly and was not fully reduced after light-chilling for 6 h in GH. Although the amplitude was small, the development of NPQ was also faster in GH, indicating a higher capacity for non-photochemical energy dissipation. The relative fraction of a fast relaxing component of NPQ (qf) was higher in GH. After light-chilling for 5 h, the values of qf in BB and GR became much smaller than that in GH, indicating BB and GR suffered more significant uncoupling of ATPase and/or irreversible damages in PSII. When fluorescence induction transients were recorded after chilling, significant differences in quenching coefficients (qQ and qN) were observed among the three cultivars.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4267-4271
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• 2013

Background: As natural medicines in Asia, curcumin and triptolide extracted from different drug plants have proven to possess anticancer potential and widely used for anti-cancer research. The present study attempted to clarify that curcumin and triptolide synergistically suppress ovarian cancer cell growth in vitro. Methods: To test synergic effects, cell viability and apoptosis were analyzed after curcumin and triptolide combination treatment on ovarian cancer cell lines. Synergistic effects on apoptosis induction were determined by lactate dehydrogenase (LDH) leakage assay, intracellular reactive oxygen species (ROS) assay, mitochondrial membrane potential (MMP) loss assay and flow cytometry analysis. Critical regulators of cell proliferation and apoptosis related were analyzed by qRT-PCR and Western blotting. Results: We showed that the combination of curcumin and triptolide could synergistically inhibit ovarian cancer cell growth, and induce apoptosis, which is accompanied by HSP27 and HSP70, indicating that HSP27 and HSP70 play the important role in the synergic effect. Conclusions: From the result present here, curcumin and triptolide combination with lower concentration have a synergistic anti-tumor effect on ovarian cancer and which will have a good potential in clinical applications.

• The Journal of Korean Obstetrics and Gynecology
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• v.28 no.2
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• pp.15-25
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• 2015

Objectives : In this study, we investigated the anti-proliferative and apoptosis inducing effect of water extract of Chelidonium majus (CM) on human breast cancer cell MDA-MB-231. Methods : The MTT assay was used to assess cell proliferation. The expression of apoptosis related gene was assessed by quantitative Real-time PCR. Cell apoptosis detected by flow cytometry using Annexin-V/PI staining. Results : Our data revealed that CM inhibited the cell growth in a dose dependent manner (0, 62.5, 125, 250, 500 μg/ml). CM increased mRNA expression of pro-apoptotic genes Bax, caspase-3, and caspase-9. Annexin-V/PI staining assays revealed that apoptosis-induced cell death increased in a dose-dependent manner in cells. Conclusions : CM induces cell death in MDA-MB-231 human breast cancer cell and shows potentials for use in cancer therapy as apoptosis-inducing agent.

• Journal of the Korean Ceramic Society
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• v.30 no.1
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• pp.46-54
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• 1993

$\beta$-SiC was chemically vapor deposited by pyrolysis of MTS＋H2 gas mixture. The experiments were conducted in the temperature range of 1100~150$0^{\circ}C$ with a r.f. induction furnace under atmospheric pressure. The IR, XRD, EDS and AES analysis revealed that the free Si was always codeposited with SiC below 140$0^{\circ}C$, regardless of the total flow rate and MTS concentration, whereas $\beta$-SiC single phase was deposited at 150$0^{\circ}C$. C3H8 or CH2Cl2 as an excess C sources, was supplied with MTS in order to obtain stoichiometric SiC at low temperature. With the addition of C3H8 or CH2Cl2, the deposition rate was increased and $\beta$-SiC single phase could be deposited even at temperature as low as 110$0^{\circ}C$. In the absence of C3H8 or CH2Cl2, the microhardness of the layer was quite low (

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5507-5513
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• 2015

Momordica cochinchinensis Spreng (MC) has been used in traditional medicine due to its high carotenoid content. The objective of this study was to investigate mechanisms underlying apoptotic effects of MC on human MCF-7 breast cancer cells. A lycopene-enriched aril extract of MC (AE) showed cytotoxicity and antiestrogenicity to MCF-7 cells. On DAPI staining, AE induced cell shrinkage and chromatin condensation were evident. With flow cytometric analysis, AE increased the percentage of cells in an early apoptosis stage when compared with the control group. RT-PCR analysis showed AE to significantly increase the expression of the proapoptotic bax gene without effect on expression of the anti-apoptotic bcl-2 gene. Moreover, AE enhanced caspase 6, 8 and 9 activity. Taken together, we conclude that AE of MC fruit has anticancer effects on human MCF-7 breast cancer cells by induction of cell apoptosis via both intrinsic and extrinsic pathways of signaling.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5863-5868
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• 2015

Nicotine-derived nitrosamine ketone (NNK) is considered a key tobacco smoke carcinogen inducing lung tumors. Physalis peruviana L (harankash) is considered one plant with marked health benefits. This study aimed to evaluate Physalis peruviana L effect on the toxic effect of NNK induced lung cancer in the rats by using pulmonary histopathological, immunohistochemical and DNA flow cytometric analyses. Sixty adult male rats were divided into four groups, each consisting of fifteen animals. The first group received saline, the second received two successive toxic doses of NNK only while the third received two successive toxic doses of NNK with a single daily dose of Physalis peruviana L. The fourth group received a single daily dose of Physalis peruviana L only. Toxic doses of NNK induced hyperplasia and adenocarcinoma in the lung and positive immunoreactivity for Ki-67 and p53 staining with disturbance of the lung DNA content. Administration of Physalis peruviana L with NNK led to a mild pulmonary hyperplasia and weak expression of Ki-67 and p53 with an improvement in the lung DNA content. Physalis peruviana L may protect against NNK induced lung carcinogenesis due to its antioxidant and anti-proliferative effects.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3073-3076
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• 2012

Terpinen-4-ol is a terpene found in the rhizome of Plai (Zingiber montanum (Koenig) Link ex Dietr.). In this study apoptogenic activity and mechanisms of cell death induced by terpinen-4-ol were investigated in the human leukemic MOLT-4 cell line. Terpinen-4-ol exhibited cytotoxicity in MOLT-4 cells, with characteristic morphological features of apoptosis by Wright's staining. The mode of cell death was confirmed to be apoptosis by flow cytometric analysis after staining with annexin V-FITC and propidium iodide. A sub-G1 peak in DNA histograms of cell cycle assays was observed. Terpinen-4-ol induced-MOLT-4 cell apoptosis mediated through an intrinsic pathway involving the loss of mitochondrial transmembrane potential (MTP) and release of cytochrome c into the cytosol. In addition, terpinen-4-ol also induced apoptosis via an extrinsic pathway by caspase-8 activation resulting in the cleavage of cytosolic Bid. Truncated-Bid (tBid) translocated to mitochondria and activated the mitochondrial pathway in conjunction with down-regulation of Bcl-2 protein expression. Caspase-3 activity also increased. In conclusion, terpinen-4-ol can induce human leukemic MOLT-4 cell apoptosis via both intrinsic and extrinsic pathways.

• BMB Reports
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• v.46 no.2
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• pp.73-79
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• 2013

Polycystic kidney disease (PKD) is a common hereditary disorder which is characterized by fluid-filled cysts in the kidney. Mutation in either PKD1, encoding polycystin-1 (PC1), or PKD2, encoding polycystin-2 (PC2), are causative genes of PKD. Recent studies indicate that renal cilia, known as mechanosensors, detecting flow stimulation through renal tubules, have a critical function in maintaining homeostasis of renal epithelial cells. Because most proteins related to PKD are localized to renal cilia or have a function in ciliogenesis. PC1/PC2 heterodimer is localized to the cilia, playing a role in calcium channels. Also, disruptions of ciliary proteins, except for PC1 and PC2, could be involved in the induction of polycystic kidney disease. Based on these findings, various PKD mice models were produced to understand the roles of primary cilia defects in renal cyst formation. In this review, we will describe the general role of cilia in renal epithelial cells, and the relationship between ciliary defects and PKD. We also discuss mouse models of PKD related to ciliary defects based on recent studies.

• The Journal of Korean Medicine
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• v.22 no.4
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• pp.37-44
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• 2001

Objectives : Cellular death by apoptosis is an active process, depending on gene transcription and protein synthesis. It was reported that nitric oxide can induce apoptosis in several cancer cell-lines. We have previously observed that proliferation of Ll210 cells was inhibited by the administration of Gleditsiae Spina water extract (GE). In this present study, the mechanism of inhibitory action on the proliferation of L l210 cells was examined. Methods : The cell proliferation was determined by MTT assay and DNA fragmentation was determined by a flow cytometry. Results : The administration of GE decreased proliferation of L1210 cells and enhanced DNA fragmentation in vivo system. DNA fragmentation of L1210 cells was enhanced by co-culture of peritoneal macrophages obtained from GE-administered mice in vitro and it was partly inhibited by L-NMMA, nitric oxide synthetase inhibitor. In addition, GE increased nitric oxide production from peritoneal macrophages of L1210-transplanted mice. Conclusions : These results suggest that the inhibitory action of GE on proliferation of transplanted-L1210 cells is partly caused by an induction of apoptosis via production of nitric oxide in macrophages.