• Radiation Oncology Journal
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• v.15 no.2
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• pp.79-95
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• 1997

Purpose : Phospholipase C(PLC) isozymes play significant roles in signal transduction mechanism. $PLC-\gamma$ 1 is one of the key regulatory enzymes in signal transduction for cellular proliferation and differentiation. Ras oncoprotein, EGFR, and PKC are also known to be involved in cell growth. The exact mechanisms of these signal transduction following irradiation, however, were not clearly documented Thus, this study was Planned to determine the biological significance of PLC, ras oncoprotein, EGFR, and PKC in damage and regeneration of rat intestinal mucosa following irradiation. Material and Method : Sixty Sprague-Dawley rats were irradiated to entire body with a single dose of 8Gy. The rats were divided into S groups according to the sacrifice days after irradiation. The expression of PLC, ras oncoprotein, EGFR and PKC in each group were examined by the immunoblotting and immunohistochemistry. The histopathologic findings were observed using H&I stain, and the mitoses for the evidence of regeneration were counted using the light microscopy & PCNA kit. The Phosphoinositide(PI) hydrolyzing activity assay was also done for the indirect evaluation of $PLC-\gamma$ 1 activity. Results: In the immunohistochemistry , the expression of $PLC-{\beta}$ was negative for all grøups. The expression of $PLC-{\gamma}1$ was highest in the group III followed by group II in the proliferative zone of mucosa. The expression of $PKC-{\delta}1$ was strongly positive in group 1 followed by group II in the damaged surface epithelium. The above findings were also confirttled in the immunoblotting study. In the immunoblotting study, the expressions of $PLC-{\beta}$, $PLC-{\gamma}1$, and $PKC-{\delta}1$ were the same as the results of immunohis-tochemistry. The expression of ras oncoprctein was weakly positive in groups II, III and IV. The of EGFR was the highest in the group II, III, follwed by group IV and the expression of PKC was weakly positive in the group II and III. Conclusion: $PLC-{\gamma}1$ mediated signal transduction including ras oncoprotein, EGFR, and PKC play a significant role in mucosal regeneration after irradiation. $PLC-{\delta}1$ mediated signal transduction might have an important role in mucosal damage after irradiation. Further studies will be necessary to confirm the signal transduction mediating the $PKC-{\delta}1$.

• Journal of the Korean Geographical Society
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• v.31 no.2
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• pp.160-197
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• 1996

The purpose of this study is to review research trends and issues of economic geography in Korea for the last fifty years by sub-fields of agricultural geography, industrial geography, commercial and service geography, and transportation geography. Research in Korean economic geography has progressed significantly in terms of the scope and the number of papers published during the last a half a century. Agricultural geography was a leading field of economic geography in Korea before mid-1970s. Since the mid-1970s, however, agricultural geography has turned over the leading role in economic geography to industrial geography. Classification and structure of agricultural region has been the most popular research theme in Korea, even though diverse topics has been dealt in the research of agricultulal geography in Korea during the last fifty years. In recent years, emphasis is given to study on the dynamics of agricultural region and regional differentiation of part-time farming. It is suggested that the future issues of research in agricultural geography in Korea are agricultural restructuring and changes in agricultural space under the WTO system, changes in rural area and agricultural region with the progress of informatization, changes in agricultural structures and rural society by the increase of part-time farming, governments agricultulal policy and its impacts, competitive advantages of Korean agricultulal products, and environmental impacts of agricultural restructuring. Research in industrial geography has remarkably progressed since the 1980s. Locational changes, regional industrial structure and formation of industrial region were the major topics of interest in the research of industrial geography in Korea before 1980. Since the early 1980s, in addition to the topics which were interested in before 1980, changes of industrial organization and industrial location, changes of production systems and industrial space development of high technology industries and science parks, industrial restructuring and regional economy, foreign direct investments, industrial linkages and industrial districts, and industrial policy and regional development have been the major research themes of industrial geography in Korea. Considerable number of papers has been published both in Korean journals and in foreign journals during this period. Considering global changes in the organization of industrial space, future research should be more focused on firms strategy for regaining competitive advantages, local and global perspectives of industry, industry and environmental changes, in addition to the topics which have been dealt in recent years. Research in commercial and service geography and transportation geography was negligible in Korea before the late 1970s. These two sub-fields in economic geography have begun to develop since 1980s. Periodic markets, structure of commercial area, and distribution of products were the major topics of interest in the 1980s in the commercial and service geography in Korea. In the 1990s, however reserch in producer services has been active with growth of producer services in Korean economy. It is suggested that regional changes with progress of informatization and technology, changes of international trade and regional changes, development of efficient distribution system, role of producer services in regional development, and network of producer services are the major issues to be studied in the future in the field of commercial and service geography in Korea. Commuting, distribution of products, and transportation networks have been the major topics of research in transportation geography in Korea. Diverse quantitative techniques have been applied in the most of the researches in transportation geography. It is required that future studies in transportation geography should also focus on societal and behavioral issues, policy issues regional impacts of new transportation facilities, an analysis of transportation system at the global or international level. Since the 1980s economic geography in Korea has considerably progressed with publication of papers and books. The progress can be regarded as successful in quantitative aspect, but not in quantitative aspects. For the development of Korean economic geography in both quantitative and qualitative aspects, it is necessary to promote international collaborative researches and interdisciplinary cooperations. Attention should also be given to the research on changes in competitive advantages and economic restructuring, changes of economic space with the development of high technology and the progress of informatization. economic development and culture. and foreign regional studies.

• Tuberculosis and Respiratory Diseases
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• v.59 no.2
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• pp.142-150
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• 2005

Background : Continuous growth stimulation by various factors, as well as chronic oxidative stress, may co-exist in many solid tumors, such as lung cancer. A new family of antioxidant proteins, the peroxiredoxins (Prxs), have been implicated in the regulation of many cellular processes, including cell proliferation, differentiation and apoptosis. However, a real pathophysiological significance of Prx proteins, especially in lung disease, has not been sufficiently defined. Therefore, this study was conducted to investigate the distribution and expression of various Prx isoforms in lung cancer and other pulmonary conditions. Method : Patients diagnosed with lung cancer, and who underwent surgery at the Ajou Medical Center, were enrolled. The expressions of Prxs, Thioredoxin (Trx) and Thioredoxin reductase (TR) were analyzed using proteomic techniques and the subcellular localization of Prx proteins was studied using immunohistochemistry on normal mouse lung tissue. Result : Immunohistochemical staining has shown the isoforms of Prx I, II, III and V are predominantly expressed in bronchial and alveolar lining epithelia, as well as in the alveolar macrophages of the normal mouse lung. The isoforms of Prx I and III, and thioredoxin were also found to be over-expressed in the lung cancer tissues compared to their paired normal lung controls. There was also an increased amount of the oxidized form of Prx I, as well as a putative truncated form of Prx III, in the lung cancer samples when analyzed using 2-dimensional electrophoresis. In addition, a 43 kDa intermediate molecular weight protein band, and other high molecular weight bands of over 20 kDa, recognized by the anti-Prx I antibody, were present in the tissue extracts of lung cancer patients on 1-Dimensional electrophoresis, which require further investigation. Conclusion : The over-expressions of Prx I and III, and Trx in human lung cancer tissue, as well as their possible chaperoning function, may represent an attempt by tumor cells to adjust to their microenvironment in a manner advantageous to their survival and proliferation, while maintaining their malignant potential.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.271-284
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• 1994

Purpose : Phospholipase C(PLC) isozymes play significant roles in transmembrane signal transduction. PLC-${\gamma}1$ acts as the intracellular effector in signal transduction for cellular proliferation and differentiation. Ras oncoprotein is also involved in cell growth. We determined the biological significance of PLC and ras oncoprotein in regeneration following radiation and the effect of different modes of administration of 5-FU. Materials and Methods : To determine the effect of the administration mode of 5-FU on the regeneration of intestinal mucosa of rats following radiation, we compared the expression of PLC and ras oncoprotein in six groups. Group I had no treatment. Group II received radiation(8 Gy) only. Group III received radiation(8 Gy) and 5-FU(150mg/kg) continuous intravenous (iv) infusion for 12 hours. Group IV received radiation(8 Gy) and 5-FU(750mg/kg) iv bolus injection. Group V received only 5-FU(150mg/kg) continuous iv infusion for 12 hours, Group VI received only 5-FU (150mg/kg) iv bolus injection. Through immunoblotting and immunohistochemistry, we examined the expression of PLC and ras oncoprotein in rat jejunum at 96 hours after radiation or 5-FU administration and at 120 hours after radiation and 5-FU adminstration. We also investigated the histological findings using hematoxylin and eosin stain. Results : In the immunohistochemistry study, PLC-${\gamma}1$ expression was the highest in group III followed by groups II and VI in that order and was weakly positive in groups V and VI. PLC-${\gamma}1$ was hardly detected in the control group. The expression of ras oncoprotein was the same as the PLC-${\gamma}1$ expression for all groups. These results were confirmed by the histological findings regarding the mucosal regeneration. In the immunoblotting analysis, PLC-${\gamma}1$ expression was the highest in group III followed by group IV and II in that order. This difference between the immunoblotting and immunohistochemistry study was due to the high expression of PLC-${\gamma}1$ on the damaged surface epithelium rather than to its expression in the regeneration region as observed in the immunohistochemistry study for group IV. The expression of PLC-${\delta}1$ was positive only in group V and VI, which received both radiation and 5-FU, and the expression of PLC-${\beta}1$ was negligible for all groups. Conclusion : These results suggest that PLC-${\gamma}1$ mediated signal transduetion and ras oncoprotein may have a significant role in mucosal regeneration after radiation, and that continuous iv infusion of 5-FU may induce active regeneration in intestinal mucosa following radiation. In addition, the expression of PLC-${\delta}1$ in combined group of radiation and 5-FU implies that PLC-${\delta}1$ may be involved in signal transduction mediated by concerted action between radiation and 5-FU.

• Tuberculosis and Respiratory Diseases
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• v.46 no.3
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• pp.327-337
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• 1999

Background: Reactive oxygen species are involved in multi-stage process of carcinogenesis. The moot of cancer cell lines and cancer cells in tumor tissue produce reactive oxygen species and on the other hand, the activities of catalase, Mn- and CuZn-superoxide dismutase in tumor cells are usually low. These persistent oxidative stress in tumor tissue facilitates tumor invasion and metastasis. 12-kDa thioredoxin, which regulates the intracellular redox potential with glutathione and glutaredoxin is involved in cell activation, proliferation, differentiation and redox-mediated apoptosis. It is also purified as 14-kDa and 10-kDa eooinophilic cytotoxic enhancing factor(ECEF) from human histiocytic cell(U937) and 10-kDa ECEF has more than 20 times eosinophilic stimulation activity than 14-kDa ECEF. It has been reported that adult T-cell leukemia, squamous cell carcinoma of uterine cervix, and hepatocellular carcinoma show increased amounts of human thioredoxin and thioredoxin mRNA is increased in lung cancer. In this study, we investigated the expression of conventional antioxidant enzymes such as catalase, CuZn-SOD, and glutathione peroxidase and thioredoxin in lung cancer tissue compared to adjacent normal lung tissue and the induction of thioredoxin in macrophage cells after treatment of oxidative stress and endotoxin Methods: We measured the amount of conventional antioxidant enzymes such as catalase, CuZn-SOD, and glutathione peroxidase and thioredoxin in lung cancer tissue compared to adjacent normal lung tissue by immunoblot analysis and the induction of thioredoxin in mouse monocyte-macrophage cells(RAW 264.7) by treatment of 5 ${\mu}M$ menadione and 1 ${\mu}g/ml$ endotoxin Results: On immunoblot analysis, the expression of 12-kDa thioredoxin was increased in lung cancer tissue compared to paired normal lung tissue. but the expression of catalase and CuZn-SOD were decreased in lung cancer tissue compared to paired normal tissue and the expression of glutathione peroxidase in lung cancer was variable. The expression of truncated thioredoxin was also increased in lung cancer. When mouse monocyte-macrophage cells were treated with 5 ${\mu}M$ menadione and 1 ${\mu}g/ml$ endotoxin, the expression of thioredoxin was peaked at 12 hrs and sustained to 48 hrs. Conclusion: In contrast with other conventional antioxidants, the expression of 12-kDa and truncated thioredoxin in lung cancer were increased and it is closely associated with persistent oxidative stress in tumor microenvironment. Considering especially the biological functions of truncated thioredoxin, the increased amount of truncated thioredoxin has significant role in tumor growth through cell proliferation.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.702-709
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• 2003

Purpose : $IFN{\gamma}$ sentitizes many tumor cells to $TNF{\alpha}$ and FASL-mediated apoptosis by enhancing the expression of TNF or FAS/CD95 receptor and modulating the activation of caspase and Bcl-2 family. It has been reported that $IFN{\gamma}$ and $TNF{\alpha}$ synergistically caused differentiation and growth inhibition of neuroblastoma cells. Even though some neuroblastoma cell express FASR/FASL on the cell surface, they could not induce apoptosis by ligation of the FAS/CD95 receptor. But the treatment of $IFN{\gamma}$ is reported to induce apoptosis in some neuroblastoma cell lines through the CD95/CD95L autocrine circuit. In this study, we examined whether $IFN{\gamma}$ could affect $TNF{\alpha}$ and agonistic FAS/CD95 antibody(CH-11)-induced apoptosis against neuroblastoma cell lines that had shown diverse drug sensitivity and resistance. Methods : CHLA-15, CHLA-90 and LA-N-2 neuroblastoma cells were cultured in IMDM and treated with recombinant $IFN{\gamma}$, $TNF{\alpha}$ and CH-11 antibody. Cell viability was measured by DIMSCAN with a fluorescent calcein-AM. Apoptosis was analyzed through flow cytometry using Annexin V-PE and 7-ADD staining and confirmed by pancaspase and caspase-8 blocking experiments. The expression of TNF RI and FAS/CD95 receptor was evaluated by flow cytometry using the corresponding antibody and PE-conjugated secondary antibody. Results : $IFN{\gamma}$ or $TNF{\alpha}$ alone had no demonstrable cytotoxic effects, whereas both cytokines in combination induced apoptosis synergistically in CHLA-15 and CHLA-90 cells. Although there was no cytotoxicity with the ligation of CH-11 alone in CHLA-90 cells, pretreatment of $IFN{\gamma}$ increased the sensitivity of CH-11-mediated apoptosis. The expression of TNFRI and FAS/CD95R were non-specifically enhanced after treatment of $IFN{\gamma}$ without relation to sensitivity to $TNF{\alpha}$ and CH-11. This finding suggest up-regulation of both receptors may contribute to sensitization of $TNF{\alpha}$ and CH-11-mediated apoptosis by $IFN{\gamma}$ in only sensitive cell lines. Conclusion : $IFN{\gamma}$ induced sensitization of $TNF{\alpha}$ and agonistic FAS/CD95 antibody-mediated apoptosis on some neuroblastoma cells through up-regulation of TNFRI and FAS/CD95 receptor.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.3 no.2
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• pp.65-88
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• 2008

To achieve the age of 30,000 dollars GNP, The business with speed will hold a more crucial point than the business with scale, and the mass consumption market will be transformed and changed into the niche market. Moreover, it will not be easy for the company without the peculiar and creative technology to survive in the severe competition. Under these circumstances, The innovative company which knows how to use this new paradigm will select the better position in the changing market. Innovation type SMEs are contributing in maintaining the international competitiveness of domestic economy by serving high-tech and the promotion of employment. Also, Innovation type SMEs have the most important economic leverage in our domestic economy. It's a source of the growth in domestic economy. Therefore, A lot of countries have been trying to support innovation type SMEs (with a small capital and high-tech). And many countries also try to protect and promote the innovation type SMEs. Especially the Korean government is also promoting innovation type SMEs in many ways, because the future of innovation type SMEs are not bright. This study explored the three innovative SEMs and studied 1) entrepreneur characteristics, 2) the industry environment, 3) competitive strategies, and 4) resources and capabilities of organization, which have been considered as the success factors for entrepreneurial firms. This study also holds that the characteristics of entrepreneurs is one of the most important factor to impact the success of innovative SMEs. Most of entrepreneurs have started their business with high education career and field experiences and have high intentions in developing new/high techonologies, challenging spirits, and clear vision and goals. The innovative SMEs with small kinds of products and services, narrow market, and small resources are more sensitively impacted by the environment especially. But the SMEs which entered into market early could have the comparative excellencies in their market to survive and grow in the future. They also have competitive advantages in the market using differentiation strategies by technology innovation. Technology innovation and differention strategies are one of the success factors in SMEs, They entered into the niche market using this weapons. The capabilities of changing organization to their changing environment, the open orgarnization culture, the continuous employment education, and the building the organic organization are also success factors of innovative SMEs. The SMEs with the simple organization structure can make fast decisions and operate with the autonomous and flexible ways. These only three cases will not shown successful factors of over 12,000 Innovation type SMEs in Korea and this study of Innovation type SMEs is insufficient from all aspects. But this study have many implications for the future research and the entrepreneurs ready for their business.

• Journal of Mushroom
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• v.19 no.4
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• pp.300-309
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• 2021

This study was conducted to develop food and medicinal products containing useful components of Lentinula edodes in Codonopsis lanceolata and Platycodon grandiflorus for use as herbal medicine. We manufactured C. lanceolata (FCLM) and P. grandiflorus (FPLM) extract fermented with L. edodes mycelium. The effect of the two fermented products on proximate composition, free sugar, organic acid, 𝛽-glucan, ergothioneine, ergosterol, and vitamin D₂ levels, and 3T3-L1 preadipocyte cell growth were studied. The proximate composition analysis results showed that the crude fiber and crude fat content in FCLM was higher than that in FPLM, and the crude protein and soluble nitrogen content in FPLM was higher than that in FCLM. Free sugar analysis detected arabinose, glucose, and sucrose in both FCLM and FPLM, and the total free sugar content was high in FPLM. The organic acid content was lower in FCLM and FPLM compared to C. lanceolata and P. grandiflorus before fermentation. The 𝛽-glucan content was higher than that of L. edodes used as a control in both fermented products, FCLM and FPLM. The content of ergothioneine, an antioxidant, was higher in FCLM than in FPLM. Ergosterol content was highest in L. edodes which was used as a control, and the two fermented products showed similar content. Vitamin D₂ was detected only in FCLM and FPLM, and FPLM (0.58±0.01 mg%) showed a higher vitamin D₂ content than FCLM (0.47±0.01). FCLM and FPLM showed a higher level of cell viability for 3T3-L1 pre-adipocytes compared to non-fermented C. lanceolata and P. grandiflorus. In addition, FCLM and FPLM inhibited 3T3-L1 preadipocyte differentiation more than C. lanceolata and P. grandiflorus before fermentation, which may exert an anti-obesity effect.

• Journal of Life Science
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• v.16 no.6
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• pp.1014-1028
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• 2006

This study attempted to investigate the developmental alterations of the cerebral cortex. The effects of EGEE on the developmental cerebral cortex in the prenatal, postnatal and adults were examined by lectin histochemical methods. To investigate the change of sugar residues of glycoconjugates, biotinylated lectins(DBA, SBA, PNA, BSL-1, RCA-1, sWGA, UEA-1, Con A and LCA) were detected with by IHC using ABC kit. In the case of injection of EGEE, the reactions to Con A and LCA were shown in binding phase in the cerebral cortex commonly, and the reactions to PNA, RCA-1 and LCA were shown partially, the number of lectins to be shown reaction were decreased, and there were no reactions to DBA, SBA, BSL-1, RCA-1 and UEA-1. The reaction to Con A was similar to control group during developmental phases. The reaction to LCA was increased in the fetal, suckling, and weanning phases compared with control group. But there were no reactions to SBA and sWGA, the reaction to PNA was decreased in the frontal and occipital cortex and no reaction to sWGA in the fetal phase. There were no reactions to sWGA and PNA in the suckling phase and, no reaction to PNA and sWGA. The reaction to Con A was decreased in the frontal, parietal and occipital cortexes and, the reaction to LCA was decreased in the frontal and occipital cortexes in adult phase. As the results, the effects of EGEE, environmental hormone on the each part of cerebral cortex have shown differences. But, It had deep effect on the differentiation and growth in the cerebral cortex pathologically. In particular, the effect was severe in suckling phase. $Galactosyl-({\beta}-1,3)-N-acetyl-D-galactosamine$,${\beta}-N-acetyl-D-galactosamine$ and ${\beta}-N-acetyl-D-glucosamine$ were decreased while ${\alpha}-D-mannose$ and ${\alpha}-D-glucose$ were increased. It affected the sugar metabloism, and it was severe in fetal and suckling phases.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.350-364
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• 1999

The distribution of mast cells and nerves were investigated in the submandibular and sublingual glands of postnatal rats, using morphometric, histochemical and immunohistochemical techniques. Mast cells were observed in the submandibular and sublingual glands of postnatal development. Number of mast cells gradually increased in both glands following development. At birth, mast cells were relatively fewer in submandibular gland than those in sublingual gland, and they were mainly distributed in parenchymal tissues. At $2{\sim}4$ weeks, most of the mast cells were observed in the connective tissues, surrounding neurovascular elements, but some mast cells were closely related with the acini of submandibular gland. PGP 9.5 immunoreactive nerve fibers were found in the submandibular and sublingual glands of all developmental age. The nerve fibers were showed in varicose shape, and mainly located in adjacent area of ducts and vascular components of both glands. The number of nerve fibers were increased rapidly until 8 weeks, but they were not increased any more until 24 weeks. Therefore, it is suggested that mast cells and nerve fibers related with each other, and that their interactions may play roles not only in maturation of secretory units but also growth and differentiation of the tubular structures of the rat submandibular and sublingual glands during postnatal development.