• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.854-860
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• 2004

"Research and Development of Melt-Growth Composite (MGC) Ultra High Efficiency Gas Turbine System Technology" program has been started in JFY2001. The main objective of the program is to establish basic component technologies to apply MGC material to an efficient gas turbine system successfully. It is known that MGC material maintains its mechanical strength at room temperature up to about 2000 K, which is ideal for the high temperature gas turbine. The purposes of the present study are to develop the cooling structure of the gas turbine combustor liner where MGC material is applied as the heat shield panel, also to develop the low NOx combustion system for a 1970 K (1700 deg.C) class gas turbine combustor. To start with, basic heat transfer characteristics were investigated by one-dimensional calculation and heat transfer experiment for the cooling structure. Axially staged configuration and fuel preparation were investigated by CFD calculation and experiments for the low NOx combustor.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5433-5438
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• 2015

Background: Systemic chemotherapy for patients with metastatic gastric cancer (MGC) is generally palliative, although some patients experience long-term survival after treatment. Thus, we identified clinical characteristics that are associated with long-term survival of patients with MGC after palliative chemotherapy. Materials and Methods: We retrospectively reviewed 514 MGC patients who received systemic chemotherapy at our institution from 2001 to 2008. To identify clinical predictors of survival beyond 2 years, multivariate logistic regression analyses were performed, and 5-year survival rates were estimated among MGC patients following chemotherapy. Results: Among 514 patients, 96 (19%) and 16 (3%) survived beyond 2 and 5 years, respectively, and performance status of 0 or 1 (odds ratio [OR]=3.39; p=0.01), previous gastrectomy (OR=1.86; p=0.01), single metastatic site (OR=1.80; p=0.03), and normal alkaline phosphatase levels (OR=2.81; p<0.01) were identified as independent predictors of long-term survival. Of the 16 5-year survivors, six were alive at the end of the study and showed no evidence of disease despite cessation of chemotherapy. Conclusions: The present data demonstrate distinct clinical characteristics that are associated with long-term survival of MGC patients, and indicated that palliative chemotherapy can be curative in highly selected patients.

• Molecules and Cells
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• v.39 no.10
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• pp.742-749
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• 2016

The cancer chemo-preventive effects of equol have been demonstrated for a wide variety of experimental tumours. In a previous study, we found that equol inhibited proliferation and induced apoptotic death of human gastric cancer MGC-803 cells. However, the mechanisms underlying equol-mediated apoptosis have not been well understood. In the present study, the dual AO (acridine orange)/EB (ethidium bromide) fluorescent assay, the comet assay, MTS, western blotting and flow cytometric assays were performed to further investigate the pro-apoptotic effect of equol and its associated mechanisms in MGC-803 cells. The results demonstrated that equol induced an apoptotic nuclear morphology revealed by AO/EB staining, the presence of a comet tail, the cleavage of caspase-3 and PARP and the depletion of cIAP1, indicating its pro-apoptotic effect. In addition, equol-induced apoptosis involves the mitochondria-dependent cell-death pathway, evidenced by the depolarization of the mitochondrial membrane potential, the cleavage of caspase-9 and the depletion of Bcl-xL and full-length Bid. Moreover, treating MGC-803 cells with equol induced the sustained activation of extracellular signal-regulated kinase (ERK), and inhibiting ERK by U0126, a MEK/ERK pathway inhibitor, significantly attenuated the equol-induced cell apoptosis. These results suggest that equol induces mitochondria-dependent apoptosis in human gastric cancer MGC-803 cells via the sustained activation of the ERK1/2 pathway. Therefore, equol may be a novel candidate for the chemoprevention and therapy of gastric cancer.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.103-107
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• 2009

Three traditional Chinese medicines, Agrimonia pilosa Ledeb, Grifola umbellata (pers.) Pilat, and Gambogia, are combined to form a compound extract, AGC. In this study, the in vitro and in vivo inhibitory effects of AGC on human gastric carcinoma MGC-803 cells were demonstrated, and the molecular mechanisms underlying these effects are investigated. Our results indicate that AGC inhibited MGC-803 cell growth in a dose-dependent manner as measured by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, with an $IC_{50}$ of about $6.045{\pm}0.69{\mu}g/mL$. In vivo, AGC inhibited growth of human gastric carcinoma in xenograft tumors in nude mice, and the inhibitory rate reached 55.2% at 300 mg/kg. The pro-apoptotic activity of AGC was attributed to its ability to decrease the expression of Bcl-2 and Pro-caspase3 and increase the expression of Bax. These results demonstrate that AGC can effectively induce programmed cell death and may be a promising anti-tumor drug in human gastric carcinoma.

• Journal of Ecology and Environment
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• v.35 no.4
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• pp.301-306
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• 2012

Determination of the minimum population size is an important component for the ex situ conservation of an endangered species. Here, we present the identification of collection strategies that most efficiently captured the genetic diversity of Brasenia schreberi J.F. Gmelin (water-shield) in natural populations from the mainland (MGC) and Jeju Island (JNS) of South Korea, using amplified fragment length polymorphism (AFLP) markers. A total of 313 and 383 polymorphic bands were detected in the MGC and JNS populations, respectively. All of the 140 sampled ramets were distinguishable by the presence of distinct AFLP phenotypes. According to the simulation of the individual sampling by maximization sampling, 25 and 28 individuals captured all of the genetic diversity in the MGC population (mainland of South Korea) and the JNS population (Jeju Island), respectively. The level of genetic diversity of the core collections was similar to the entire collection, indicating that the core collections very well represent the diversity of the entire collection. We therefore suggest a management unit of B. schreberi based on the genetic information for assessing the minimum population size for its ex situ conservation.

• The Journal of Internal Korean Medicine
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• v.40 no.1
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• pp.136-144
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• 2019

Objective: The purpose of this study was to report on the alleviation of symptoms of a myasthenia gravis (MG) patient after Korean medicine treatment. Methods: A 39 year-old male patient who suffered from MG was examined. The patient was treated with herbal medicine, acupuncture, and pharmacopuncture. The Myasthenia Gravis Composite (MGC) scale and Myasthenia Gravis Activities of Daily Living (MG-ADL) profile were used to assess the change of MG symptoms after Korean medicine treatment. Results: The MGC and MG-ADL scores indicated significant improvement after 14 days of treatment. In addition, the degrees of fatigue, dyspepsia, vomiting, sweating, and dizziness were decreased. Conclusion: This study may suggest that Korean medicine treatment could be effective in treating the symptoms of MG.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1377-1382
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• 2012

Morphine is not only an analgesic treating pain for patients with cancer but also a potential anticancer drug inhibiting tumor growth and proliferation. To gain better insight into the involvement of morphine in the biological characteristics of gastric cancer, we investigated effects on progression of gastric carcinoma cells and the expression of some apoptosis-related genes including caspase-9, caspase-3, survivin and NF-${\kappa}B$ using the MGC-803 human gastric cancer cell line. The viability of cells was assessed by MTT assay, proliferation by colony formation assay, cell cycle progression and apoptosis by flow cytometry and ultrastructural alteration by transmission electron microscopy. The influences of morphine on caspase-9, caspase-3, survivin and NF-${\kappa}B$ were evaluated by semi-quantitative RT-PCR and Western blot. Our data showed that morphine could significantly inhibit cell growth and proliferation and cause cell cycle arrest in the G2/M phase. MGC-803 cells which were incubated with morphine also had a higher apoptotic rate than control cells. Morphine also led to morphological changes of gastric cancer cells. The mechanism of morphine inhibiting gastric cancer progression in vitro might be associated with activation of caspase-9 and caspase-3 and inhibition of survivin and NF-${\kappa}B$.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.5 no.1
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• pp.65-75
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• 2005

Purpose: To understand genetic differences and similarities between mucolipidosis and control. Methods: Using the fibroblast of the mucolipidosis II and control, forward and reverse subtracted libraries were constructed. Among these clones, we investigated mutations in the GNPTA (MGC4170) gene, which codes for the ${\alpha}/{\beta}$ subunits of phosphotransferase, and in the GNPTAG gene, which codes for the ${\gamma}$ subunits in 5 Korean patients with mucolipidosis type II or IIIA. Result: Several differentially expressed cDNAs were cloned and their sequences were determined. Mutation analysis of the interested gene, GNPTA was performed and we identified 7 mutations in the GNPTA gene, but none in the GNPTAG gene. The mutations in type II patients included p.Q104X(c.310C>T), p.R1189X(c.3565C>T), p.S1058X(c.3173C>G), p.W894X(c.2681G>A) and p.H1158fsX15(c.3474_3475delTA), all of which are non-sense or frame shift mutations. However, a splicing site mutation, IVS13+1G>A (c.2715+1G>A) was detected along with a non-sense or a frame shift mutation (p.R1189X or p.E858fsX3(c.2574_2575delGA)) in two mucolipidosis type IIIA patients. Conclusion: This report shows that mutations in the GNPTA gene coding for the ${\alpha}{\beta}$subunits of phosphotransferase, and not mutations in the GNPTAG gene, account for most of mutations found in Korean patients with mucolipidosis type II or IIIA.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.141.2-142
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• 2002

• Journal of radiological science and technology
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• v.11 no.2
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• pp.99-105
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• 1988