• Journal of Life Science
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• v.16 no.6
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• pp.1052-1059
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• 2006

The heat shock response is induced by environmental stress, pathophysiological state and non-stress conditions and wide spread from bacteria to human. Although translations of most proteins are stopped under a heat shock response, heat shock proteins (HSPs) are produced to protect cell from stress. When heat shock response is induced, conformation of HSF1 was changed from monomer to trimer and HSF1 specifically binds to DNA, which was called a heat shock element(HSE) within the promoter of the heat shock genes. Human HSF1(hHSFl) contains five cysteine(Cys) residues. A thiol group(R-SH) of Cys is a strong nucleophile, the most readily oxidized and nitrosylated in amino acid chain. This consideration suggests that Cys residues may regulate the change of conformation and the activity of hHSF1 through a redox-dependent thiol/disulfide exchange reaction. We want to construct role of five Cys residues of hHSF by redox reagents. According to two studies, Cys residues are related to trimer formation of hHSF1. In this study, we want to demonstrate the correlation between structural change and DNA-binding activity of HSF1 through forming disulfide bond and trimerization. In this results, we could deduce that DNA binding activity of DNA binding domain wasn't affected by redox for always expose outside to easily bind to DNA. DNA binding activity of wild-type HSF's DNA binding domain was affected by conformational change, as conformational structure change (trimerization) caused DNA binding domain.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.652-663
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• 1999

Craniosynostosis, the premature fusion of cranial sutures, presumably involves disturbance of the interactions between different tissues within the cranial sutures. Interestingly, point mutaions in the genes encoding for the fibroblast growth factor receptors(FGFRs), especially FGFR2, cause various types of human craniosynostosis syndromes. To elucidate the function of these genes in the early morphogenesis of mouse cranial sutures, we first analyzed by in situ hybridization the expression of FGFR2(BEK) and osteopontin, an early marker of osteogenic differentiation, in the sagittal suture of calvaria during embryonic(E15-E18) and postnatal stage(P1-P3). FGFR2(BEK) was intensely expressed in the osteogenic fronts, whose cells undergo differentiation into osteoprogenitor cells that ultimately lay down the bone matrix. Osteopontin was expressed throughout the parietal bones excluding the osteogenic fronts, the periphery of the parietal bones. To further examine the role of FGF-mediated FGFR signaling in cranial suture, we did in vitro experiments in E15.5 mouse calvarial explants. Interestingly, implantation of FGF2 soaked beads onto both the osteogenic fronts and mid-mesenchyme of sagittal suture after 36 hours organ culture resulted in the increase of the tissue thickness and cell number around FGF2 beads, moreover FGF4-soaked beads implanted onto the osteogenic fronts stimulated suture closure due to an accelerated bone growth, compared to FGF4 beads placed onto mid-mesenchyme of sagittal suture and BSA control beads. In addition FGF2 induced the ectopic expression of osteopontin and Msx1 genes. Taken together, these data indicate that FGF-mediated FGFR signaling has a important role in regulating the cranial bone growth and maintenance of cranial suture, and suggest that FGF-mediated FGFR signaling is involved in regulating the balance between the cell proliferation and differentiation through inducing the expression of osteopontin and Msx1 genes.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.105-138
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• 2009

Although the decline in fertility rate is generally observed along the history of economic development throughout the world, the continuing decline hitting below the replacement level in Korea over the recent years gathered serious social concerns on the ground that it accelerates the process of population aging. The total fertility rate in Koreareached 2.08 in 1983, and gradually fell to the levels of 1.08 in 2005 and 1.26 in 2007. The policy debate over the role of the government has been focused mainly on the level of theoretical discussion without substantial basis on firm empirical evidence and the determinants of fertility. The objective of the paper is to empirically investigate the fertility effect of the female wage, which is understood as one of the most important determinants of fertility in Koreasince 1980 focusing on one aspect of fertility, namely birth spacing. Using the Korean National Fertility Survey conducted in 2006, I estimate a duration model of first and second births taking into account individual heterogeneity, which turned out to be an important factor to control for. Compared with previous studies in the literature on the Korean fertility, the study has an advantage of using the complete pregnancy history of women in a more representative sample. Unlike the previous studies, the analysis also deals with the endogeneity of marriage by treating a certain age, rather than age at marriage, as the time in which a woman becomes exposed to the risk of pregnancy. The study shares the common problem in the literature on birth spacing of lacking relevant wage information for respondents in a retrospective survey. I estimate the wage series as a function of the basic characteristics using the annual Wage Structure Survey from 1980 to 2005, which is considered as a nationally representative sample for wage information of employees. The results suggest that the increase in female wage by 10 percent leads to a decrease in second birth hazard by 0.56~0.92 percentage points and that the increase in spouse's wage by the equal amount is accompanied by the increase in second birth hazard by 0.36~1.13 percentage points. These estimates are more precisely estimated and of smaller magnitude than those presented by the previous studies. The results are robust to the different specifications of the wage equation. The simulation analysis based on the predicted values shows that about 17% of the change in the second birth hazard over the period 1980 to 2005 was due to the change in the female wage. Although there is some limitation in data, the results can be viewed as one estimate of the role of female wage on the recent fertility decline in Korea. The question raised by the paper is not a normative one of whether a government should promote childbearing but a positive one thatexplains fertility decline. Therefore, if there is a wide consensus on promoting childbearing, the finding suggests that the policies designed to reduce the opportunity cost of women in the labor market would be effective. The recent movement of implementing a wide range of family-friendly policies including child care support, maternity leave, parental leave and tax benefit in developed countries should be understood in this context.

• Journal of Music and Human Behavior
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• v.2 no.2
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• pp.1-14
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• 2005

This research was to study the behavior of listening music, music preference, meaning and role of music. The interviewees were 158 male/female students of high school in second level. This research had a interview which is composed with 7 multiple choice-questions and 1 short answer-question. In result, in the question of 'The average time of listening music', the most students(64, 41.8%) answered '1~2hours', the secondary, '2~3hours' which was 32.(20.9%) In the next question, 'The preference of music genre', 87students(56.8%) answered 'Korean pop and rock', 'American pop' was 11.1% each. Regarding 'The favorite mood of music', 50.3% of students answered 'Mellow songs, 24.8% of students answered 'Jaunty songs'. Regarding 'The social factor of listening music', more than half students(56.7%) agreed that friends or something like that may affect their music preference. Likewise, 51.6% agreed that their temper or character may affect their music preference. They answered that they enjoy the music usually when they take a rest(30.1%), when in moving(24.3%). Lastly, it said 'The meaning of music' is mostly 'Getting rid of stress and Refresh'(25.1%). And 'Calmness', 'Comfort' was 21.8%. The music especially to students means 'Emotional exit'. The music which can enable them to express their feelings is related with feeling and emotion deeply. And emotional factors like stress, depression, anxiety becomes the main reason of accepting the music meaningfully. In conclusion, This research says that they experience positive feelings and express emotions through music which enables them to understand fully their feelings and emotions.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.887-897
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• 2000

Background : Since the exact pathogenesis of sepsis-induced ARDS has not been elucidated, the mechanisms of enhanced neutrophilic respiratory burst were probed in endotoxin primed neutrophils associated with the roles of phospholipase A2(PLA2), platelet activating factor(PAF) and apoptosis. Methods : In isolated fresh human neutrophils, effects of the inhibition of PLA2 and PAF on the apoptosis were examined by the method of Annexin-FITC/dual PIflow cytometry. The roles of PLA2 and PAF on the neutrophilic respiratory burst were also examined by measuring oxidant generation in cytochrome-c reduction assay. Activities of the PLA2 and lysoPAF acetyltransferase (lysoPAF AT) of the neutrophils were determined to understand the effect of endotoxin on these enzymatic activities which may be related to the neutrophilic respiratory burst and apoptosis. In addition, the role roles of PLA2 and PAF in neutrophilic adhesion to bovine endothelial cells were examined in vitro by neutrophil adhesion assay. To investigate the effect of oxidants on pulmonary surfactant, cytochemical ultrastructural microscopy was performed. To inhibit PLA2 and PAF, non-specific PLA2 inhibitor mepacrine (100 nM) and WEB 2086 (100 nM) or ketotifen fumarate (10 ${\mu}g$/ml) were used respectively in all in vitro experimental sets. WEB 2086 is PAF receptor antagonist, and ketotifen fumarate is a lyso PAF AT inhibitor. Results: The mapacrine treatment, provided and the endotoxin (ETX) treatment, resulted in increased apoptosis of neutrophils (p<0.001) while treatments of WEB 2086 and ketotifen did not. The inhibition of PLA2 and PAF decreased (p<0.001) production of oxidants from PMA-stimulated neutrophils. While endotoxin increased the PLA2 activity of neutrophils (p<0.01), mepacrine supressed (p<0.001) the activity, provided after treatment of ETX. The lyso PAF actyltransferase activity (lyso PAF AT) increased (p<0.01) after treatment of ETX. In contrast, mepacrine, WEB 2086 and ketotifen showed a tendency of decreasing the activity after treatment of ETX. The treatment of ETX incresed (p<0.001) neutrophil adhesion to endothelial cells, which was reversed by inhibition of PLA2 and PAF (p<0.01). The binding of oxidants to pu1monary surfactant was identified histologically. Conclusions : The enhanced neutrophilic respiratory burst by ETX plays a pivotal role in the pathogenesis of ARDS in terms of oxidayive oxidative stress. Increased production of oxidants from neutrophils is mediated by the activations of PLA2 and lyso PAF AT.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.835-845
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• 1998

Background: Silica-induced lung diseases is characterized by the accumulation of inflammatory cells at early stage and fibrosis in pulmonary parenchyma and interstitium at late stage. As a consequence of inflammation, silicosis is accompanied with the expansion of interstitial collagen and the formation of fibrotic nodule. In this process, several kinds of lung cells produce cytokines which can amplify and modulate pulmonary fibrosis. The alveolar macrophage is a potent source of proflammatory cytokines and growth factor. But in the process of silicotic inflammation and fibrosis, there are many changes of the kinetics in cytokine network. And the sources of cytokines in each phase are not well known. Method: 2.5 mg of silica was instillated into the lung of C57BL/6J mice. After intratracheal instillation of silica, the lungs were removed for imunohistochemical stain at 1, 2, 7 day, 2, 4, 8, 12 week, respectively. We investigated the expression of IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ in lung tissue. Results: 1) The expression of IL-6 increased from 1 day after exposure to 8 weeks in vascular endothelium. Also peribronchial area were stained for IL-6 from 7 days and reached the peak level for 4 weeks. 2) The IL-1 $\beta$ was expressed weakly at the alveolar and peribronchial area through 12 weeks. 3) The TNF-$\alpha$ expressed strongly at alveolar and bronchial epithelia during early stage and maintained for 12 weeks. 4) TGF-$\beta$ was expressed strongly at bronchial epithelia and peribronchial area after 1 week and the strongest at 8 weeks. Conclusion: The results above suggests IL-6, TNF-$\alpha$ appear to be a early inflammatory response in silica induced lung fibrosis and TGF-$\beta$ play a major role in the maintenance and modulation of fibrosis in lung tissue. And the regulation of TNF-$\alpha$ production will be a key role in modultion of silica-induced fibrosis.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.403-409
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• 2010

The purpose of this study was to examine the teaching efficiency of clinical training for dental hygiene students in Gyeonggi Province. The subjects in this study were 371 dental hygiene juniors in seven different colleges in Gyeonggi Province, on whom a self-administered survey was conducted. The collected data were analyzed with a SPSS WIN 12.0 program, and the findings of the study were as follows: 1. The teaching efficiency of clinical training that the dental hygiene students undergone was on the average. As for evaluation of the factors of teaching efficiency, they gave the highest marks to the role model factor(3.40). 2. The size of the institutions where they received clinical training made no statistically significant differences to the teaching efficiency of their clinical training. The university hospitals ranked first in professional knowledge, one of the sub-directory of teaching efficiency, and the gap between them and the others was statistically significant(p=.005). 3. Concerning links between satisfaction level with the major and view of teaching efficiency, stronger satisfaction with the major led to better perception of teaching efficiency(p=.001). Among the subdirectory of teaching efficiency, that made statistically significant differences to view of interpersonal skills, performance as a supporter, fair evaluation, academic organization skills(p=.005), encouragement and support, teaching methods, professional academic knowledge(p=.001), communicative competency, performance as a role model and cooperation with the staff of dental clinics(p=.000). 4. There were no statistically significant gaps in teaching efficiency according to teaching styles. Among the sub-directory of teaching efficiency, statistically significant differences were found only in encouragement and support(p=.005). The above-mentioned findings suggest that the teaching efficacy of the clinical training was approximately on the average, and that a better satisfaction with the major led to a higher teaching efficacy. Therefore a wide variety of teaching methods and systematic training programs should be developed to boost the quality of clinical training to improve its teaching efficacy.

• Journal of Korean Elementary Science Education
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• v.24 no.4
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• pp.391-398
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• 2005

Recent studies say that informal learning is influential to students as much as formal teaming. Nowadays we can see various informal teaming inside and outside of the country. In 2004, it was the first attempt in Korea that engineer had gone to the elementary school fur activity that included scientific experiment and engineering work with students. National Academy of Engineering of Korea (NAEK) progressed activity with companies and elementary schools for students' making sense of engineer and what they are doing. To do that, NAEK had developed the network that company could support its local school's science education circumstance by engineers' visiting program. In 2004, seventeen companies including both large and small ones took part in the program called' Korea Junior Engineering Achievement (KJEA)'. In this program, engineers played the role of teacher (we call them company teacher), elementary school teachers played the role of organizing classes as a mediator. Elementary school teachers and company teachers' recognition is very important to make students' activity meaningful. The aim of this study was to give implication for informal science education activity for which engineers visit their local school. We got the result by survey and interview of company teachers and elementary school teachers. This study's result shows that almost company teachers and school teachers were in favor of purpose of this informal science education activity and satisfied with their participation. But some company teachers were not satisfied with worksheets, materials provided and relationship between school and company). Elementary school teachers and company teachers, both of them believed students' program as the key factor of success of informal science education activity. To make informal science education grow, school administrator and teacher need to have a will to utilize the activities more actively.

• Journal of Korea Technology Innovation Society
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• v.20 no.4
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• pp.1089-1121
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• 2017

'Technological convergence' is the recent innovation trend which facilitates to solve social crux as well as to generate new industries. Korean government research institutes (GRIs) have taken a pivotal role for economic growth which capitalized on technology-oriented strategies. Recently, the policy interests on the transition of their role and mission towards multidisciplinary research organization is increasingly shed lights. This study regards the collaborative activities as one of the key success factors in the multidisciplinary research. In this sense, this study sets research purposes as follows: First, we intend to define a concept and to confine a scope of multidisciplinary research from the view point of R&D purposes and problem-solving process. Second, we categorize the collaboration and the relevant performances which reflect the characteristics of the multidisciplinary research. Third, we analyze the characteristics of collaborative activities and the effects of strength on the research performances. To this end, this study conducted a survey of 104 research project directors, which have experienced at least one of two types of multidisciplinary research projects through National R&D project or NST (National Research Council of Science & Technology) convergence research project. Then, we conducted regression analysis by utilizing the survey results in order to verify the relation between the collaborative activities and the performances. As results of analyses, first, the diversification of collaboration partners was a salient factor in the process of knowledge creation. Second, collective works among the researchers in similar area and domain enhanced mission-oriented technology development projects such as patent creation or technology transfer. Third, we verified that the diversity of created knowledge and the degree of relation continuity between researchers increased in the condition of guaranteeing individual researcher's independence and autonomy as well as sharing various technological capabilities. These results provide the future policy directions related to the methods to measure the collaboration and performance analysis for multidisciplinary research.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.469-475
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• 1998

Purpose : To determine the role of Pelvic irradiation in stage I or IIA cervical carcinoma with pelvic nodal metastasis after hysterectomy and bilateral pelvic lymphadenectomy. Materials and Methods : This is a retrospective study of 68 cervical carcinoma patients who were found to have pelvic nodal metastasis at hysterectomy and received pelvic irradiation from 1983 to 1996 at Inje University Seoul Paik Hospital. External beam radiation therapy to pelvis was delivered using 4 MeV Linac and intracavitary irradiation was given via vaginal ovoids or cylinders. Five-year survival and disease-free survival were estimated by Kaplan-Meier Method and prognostic factors related to survival were analysed by log-rank test and Cox proportional hazards regression model. Results : Median length of follow-up was 52months. Five-year overall survival and disease-free survival (DFS) were 81.8$\%$ and 81.7$\%$ respectively. Patients with endometrial invasion had a 57.1$\%$ 5-year DFS compared to 87.5$\%$ for those without endometrial invasion (p=0.0074). Multivariate analysis revealed endometrial invasion as an only statistically significant prognostic factor for 5-year DFS. Among total 15 (22$\%$) recurrences. pelvic recurrences occurred in 4 cases and distant metastases occurred in 13 cases. Conclusion : We have been able to confirm previous results demonstrating marked decrease in local recurrence after pelvic irradiation. In view of the high proportion of distant metastasis found in this study, a trial of aggressive adjuvant systemic therapy and irradiation in early stage cervical carcinoma patients with pelvic nodal metastasis, especially with endometrial invasion, appears to be warranted.