• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.841-845
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• 2003

In order for engineered tissues to find clinical utility, the engineered tissues must function appropriately. However, smooth muscle (SM) tissues engineered in vitro with a conventional tissue engineering technique may not exhibit contractile functions, because smooth muscle cells (SMCs) cultured in vitro typically revert from a contractile, differentiated phenotype to a synthetic, nondifferentiated phenotype and lose their ability to contract. SMCs in vivo typically reside in mechanically dynamic environments. We hypothesized that cyclic mechanical stretch induces the features of SMCs in in vitro engineered tissues to be similar to those of SMCs in native tissues. To test the hypothesis, aortic SMCs were seeded onto elastic, three-dimensional scaffolds and cultured in vitro under a cyclic mechanical stretching condition for 4 weeks. A significant cell alignment in a direction parallel to the cyclic stretching direction was found in the SM tissues exposed to cyclic stretching. The cellular alignment and alignment direction were consistent with those of native vascular SM tissues, in which SMCs in vivo align in the radial direction (parallel to stretching direction). In control tissues (SM tissues engineered without stretching), cells randomly aligned. The expression of SM ${\alpha}-actin$ and SM myosin heavy chain, phenotypic markers of SMCs in a contractile state, was upregulated in the stretched tissues by 2.5- and 2.0-fold, respectively, compared to SMCs in the control tissues. The cellular features of alignment and contractile phenotype of SMCs in the SM tissues engineered under a mechanically dynamic environment could allow the engineered SM tissues to exhibit contractile functions.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.405-406
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• 2008

To maintain reliable and stable power grid the Power Dispatch Center consists of two sections, primary and backup centers. It is necessary that the Backup Dispatch Center stay away from the primary center in case of emergency like terror and natural disaster. The Backup Dispatch Center operates transmission lines outside of Seoul metropolitan area and could perform main center's role when primary center lose control Without building a duplex Power IT system, it would be doubtful to operate both centers efficiently. This paper deals with primary and backup Power IT systems which run two Dispatch Centers and focuses on expectation effects of its duplex system and transferring the Backup system.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.143-144
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• 2001

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.244.1-244.1
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• 2003

Advances in understanding of pain and analgesia have been made. Over the past few years, we have designed and synthesized a series of VR agonists, based on the structures of 12-HPETE and capsaicin. the natural VR agonist. But for the development of analgesic drugs, these synthetic VR agonists had problems like burning sensation. hypothermia. etc. So our recent studoes have focused on designs and syntheses of VR antagonists based on the structure of capsaicin(natural VR agonist), and capsazepine(synthetic VR antagonist). (omitted)

• BMB Reports
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• v.54 no.11
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• pp.575-580
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• 2021

Cisplatin is widely known as an anti-cancer drug. However, the effects of cisplatin on mitochondrial function and autophagy-related proteins levels in the skeletal muscle are unclear. The purpose of this study was to investigate the effect of different doses of cisplatin on mitochondrial function and autophagy-related protein levels in the skeletal muscle of rats. Eight-week-old male Wistar rats (n = 24) were assigned to one of three groups; the first group was administered a saline placebo (CON, n = 10), and the second and third groups were given 0.1 mg/kg body weight (BW) (n = 6), and 0.5 mg/kg BW (n = 8) of cisplatin, respectively. The group that had been administered 0.5 mg cisplatin exhibited a reduced BW, skeletal muscle tissue weight, and mitochondrial function and upregulated levels of autophagy-related proteins, including LC3II, Beclin 1, and BNIP3. Moreover, this group had a high LC3 II/I ratio in the skeletal muscle; i.e., the administration of a high dose of cisplatin decreased the muscle mass and mitochondrial function and increased the levels of autophagy-related proteins. These results, thus, suggest that reducing mitochondrial dysfunction and autophagy pathways may be important for preventing skeletal muscle atrophy following cisplatin administration.

• Journal of Engineering Education Research
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• v.18 no.5
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• pp.51-58
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• 2015

This research was conducted to assess the effects of an engineering education accreditation program devised by the University of Seoul on higher education outcomes by comparing and analyzing the evaluation results of engineering accredited students (31) and those who are not accredited (47) with the OECD AHELO (Assessment of Higher Education Learning Outcomes) in 2013. The AHELO assessment tool consisted of 25 multiple-choice questions which evaluated generic skill-learning outcomes, also using contextual surveys to establish the students' backgrounds. The results were evaluated statistically. In the results from the multiple-choice exam for generic skill learning outcomes, accredited students scored 1.35 points higher than non-accredited students. Secondly, according to the contextual survey related to students' university education experience, such as lectures, seminars, group projects, and online tutoring, it was found that accredited students were provided more activities in seminars and group projects. Moreover, for class activities, more of these were provided to accredited students, especially in the areas of assortment-structuralization and teamwork-based activities. Thirdly, according to the contextual survey results related to participation in class, specifically regarding asking questions and participating in discussions, interacting with the professor, and opportunities for study time, there were no recognizable differences between accredited and non-accredited students, However, while accredited students at least had opportunities to gain experience in most areas, there were some areas for which education resources were not provided to non-accredited students. Therefore, for the University of Seoul, our results imply that accredited students may show better performance in the areas of academic accomplishment and in their educational environment as compared to non-accredited students. These results demonstrate that the engineering education accreditation program positively contributes to employment competitiveness while also improving the necessary global standards of higher education outcomes.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.2
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• pp.153-160
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• 2017

In this study, we aim to determine the in vivo effect of human umbilical cord blood-derived multipotent stem cells (hUCB-MSCs) on neuropathic pain, using three, principal peripheral neuropathic pain models. Four weeks after hUCB-MSC transplantation, we observed significant antinociceptive effect in hUCB-MSC-transplanted rats compared to that in the vehicle-treated control. Spinal cord cells positive for c-fos, CGRP, p-ERK, p-p 38, MMP-9 and MMP 2 were significantly decreased in only CCI model of hUCB-MSCs-grafted rats, while spinal cord cells positive for CGRP, p-ERK and MMP-2 significantly decreased in SNL model of hUCB-MSCs-grafted rats and spinal cord cells positive for CGRP and MMP-2 significantly decreased in SNI model of hUCB-MSCs-grafted rats, compared to the control 4 weeks or 8weeks after transplantation (p<0.05). However, cells positive for TIMP-2, an endogenous tissue inhibitor of MMP-2, were significantly increased in SNL and SNI models of hUCB-MSCs-grafted rats. Taken together, subcutaneous injection of hUCB-MSCs may have an antinociceptive effect via modulation of pain signaling during pain signal processing within the nervous system, especially for CCI model. Thus, subcutaneous administration of hUCB-MSCs might be beneficial for improving those patients suffering from neuropathic pain by decreasing neuropathic pain activation factors, while increasing neuropathic pain inhibition factor.

• Journal of Preventive Medicine and Public Health
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• v.40 no.3
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• pp.239-248
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• 2007

Objectives : This study was conducted to investigate the systematic error, such as seasonal change or inadequate food items, in a food frequency questionnaire administered to workers in a Nuclear Power Plant, Korea. Methods : We performed three repeat-tests with 28 subjects on May 13, July 8 and Dec 16, 1992. Our food frequency questionnaire (FFQ) comprised 84 foods organized into 7 food-groups, and was composed of the items of usual intake frequency (8 categories) and the amount per intake (3 or 4 categories) over the previous year. We compared the means of intake frequency and the frequency of the portion-size according to each season using Repeated Measures ANOVA and Pearson's chisquare test with Fisher's exact test. Results : We found the significant seasonal changes of several food items in intake frequency measurement. These items were typical seasonal foods such as mandarin orange, plum and green vegetables, while the single questions consisted of inadequate food items such as thick beef or similar soup and various kimchi products. Significant seasonal changes in portion-size were found in only two items: cooked rice-brown and fresh frozen fishes. Conclusions : The systematic errors observed could caused loss of validity in the FFQ. Consideration should be given for seasonal variation in FFQ survey and methodological concerns are needed to improve the quality for measuring usual diet pattern.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.2
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• pp.135-139
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• 2020

Objective: In the present study, we aimed to retrospectively evaluate the cumulative live birth rate (LBR) after up to three consecutive embryo transfer (ET) cycles, either fresh or frozen, in women with expected poor ovarian response (ePOR). Methods: We selected 115 women who entered the first in vitro fertilization (IVF) cycle between August 2013 and July 2016. The women were divided into an ePOR group (37 women) and a non-ePOR group (78 women). All women in the ePOR group were ≥ 40 years old or had serum anti-Müllerian hormone levels of less than 1.1 ng/mL at the time of the first IVF cycle. Live birth outcomes were monitored until December 2017. The cumulative LBR (with both conservative and optimistic estimates) was calculated according to the serial number of ET cycles. Results: After up to three ET cycles, the overall cumulative LBR was significantly lower in the ePOR group than in the non-ePOR group (conservative estimate, 10.8% vs. 44.9%, respectively; optimistic estimate, 14.7% vs. 56.1%, respectively; log-rank test, p= 0.003). Conclusion: Women with ePOR exhibited a lower cumulative LBR than women in the non-ePOR group, and this information should be provided to ePOR women during counseling before starting IVF.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.339.3-340
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• 2002

Capsaicin is hot taste ingredient of chili pepper and was isolated in 1876 and in 1919 its structure is sympathized compound. induces pain and when persistently dosed. the fact will bring insensible condition to other chemical and mechanical thermal stimulation by incapacitating sensory neuron is known. The analgesic effect by desensitization of such capsaicin is differ from the mechanism by analgesic action by opiate receptor of the existing analgesia or by prostaglandin mediation and the efficacy was known as similar with morphine. (omitted)