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Isolation and Culture of Purified Aortic Endothelial Cells Derived from Alpha 1, 3-galactosyltransferase-deficient Pigs (이종 장기이식 및 조직 공학을 위한 Alpha gal 유전자 결손돼지(1, 3-galactosyltransferase-deficient pigs)에서 혈관내피세포(aortic endothelial cells)의 구축)

  • Ock, Sun A;Lim, Malgum;Kim, Yeongji;Ullah, Imran;Shin, Yurianna;Kim, Youngim;Oh, Keon Bong;Hwang, Seongsoo;Hur, Tai-Young;Lee, Seunghoon;Im, Gi-Sun
    • Journal of Embryo Transfer
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    • v.32 no.3
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    • pp.87-94
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    • 2017
  • Tissue engineering (TE) has been developed to create functional organs and tissue by combining 3D matrix and cells in vitro. Vascularization and angiogenesis are utmost important for supply of nutrients and oxygen in tissue engineered organs. The present study was performed to isolate and characterize primary endothelial cells (EC) from aorta of alpha 1, 3-enzyme galactosyltransferase knock out (GalT KO) pig, to minimize immune rejection and analyze body immune system for future xenotransplantation studies. Isolation of primary EC from aorta were performed by incubation with dispase for 8-10 min at $37^{\circ}C$. Primary EC were cultured in EC growth medium on different extra cellular matrix (ECM), either collagen or gelation. Primary EC exhibits morphological characteristics and showed positive expressions of EC specific marker proteins i.e. PECAM1, KDR and VWF despite of their ECM surface; however, on collagen based surface they showed increase in mRNA level analyzed by qPCR. Primary EC cultured on collagen were sorted by flow cytometer using KDR marker and cultured as KDR positive cells and KDR negative cells, respectively. KDR positive cells showed dramatically increased in PECAM1 and VWF level as compared to KDR negative cells. Based on the above results, primary EC derived from GalT KO are successfully isolated and survived continuously in culture without becoming overgrown by fibroblast. Therefore, they can be utilize for xeno organ transfer, tissue engineering, and immune rejection study in future.

An Investigation into Oral Medicine Inpatients by Systemic Disease (전신질환으로 입원한 환자의 구강내과질환 발현실태)

  • Oh, Byung-Sub;Chun, Yang-Hyun;Hong, Jung-Pyo;Auh, Q-Schick
    • Journal of Oral Medicine and Pain
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    • v.34 no.2
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    • pp.123-132
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    • 2009
  • Purpose : To investigate the actual conditions of diagnosis and treatment of oral medicine inpatient with systemic disease. Methods : A total of 54 oral medicine subjects, inpatient due to systemic disease for diagnosis and treatment of oral disease was requested to answer the medical history and dental treatment record. Results : The ratio of gender is composed of male 44% and female 56%, the distribution of age is the order of the 50-59 group 37%, the 60-69 group 26%, the 40-49 group 22%. Systemic disease is composed of Endocrine, nutritional and metabolic diseases 36%, Diseases of the circulatory system 36%, Diseases of the nervous system 10%. Chief complain of oral disease is composed of routine check for oral health 26%, craniomandibular disorders 18%, soft tissue problem 18%. Oral disease is composed of Diseases of salivary glands 32%, Gingivitis and periodontal diseases 23%, Dentofacial anomalies 16% Conclusion : These findings indicate that oral medicine inpatient due to the systemic disease is significantly correlated to the oral disease. The patients of oral disease interrelationship between inpatient and outpatient of systemic disease should be validated by future research.

An Analysis of Maritime E-commerce Transportation between Korea and China (대중국 전자상거래 해상운송 기종점 분석)

  • Shin, Sung-Ho;Jung, Hyun-Jae;Lee, Dong-Hyon
    • Journal of Korea Port Economic Association
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    • v.34 no.3
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    • pp.93-112
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    • 2018
  • The purpose of this study is to analyze the flow of e-commerce freight transported by maritime transportation for China and to identify the characteristics of cargo by region/item for finding the ways to promote e-commerce export to China. Thus, this study analyzed the e-commerce export and import data on cargo moved via maritime transportation between Korea and China from 2015 to 1Q18, using Origin-Destination(OD) analysis and visualization techniques. The results indicated that the largest number of Chinese e-commerce cargoes were imported at Incheon Port, which has a clearance facility for e-commerce cargo. In the case of Pyeongtaek Port, e-commerce cargo imported from China has transported to Incheon Customs again, causing the inefficiency through the customs clearance process. Unlike the case of e-commerce imports where the final destination is distributed nationwide, e-commerce products exported to China through maritime transportation were found to be mainly confined to Seoul and Gyeonggi provinces, where freight forwarding companies and forwarders are concentrated. In addition, unlike e-commerce import cargoes, e-commerce items exported through maritime transportation were mainly confined to clothing and cosmetics, and export volume was also less than imports. This study provides some possible strategies to increase the volume of freight and to attract export products as follows: i) to diversify products exported to China through e-commerce transshipment, ii) to diversify export items by building the cold chain in e-commerce transport with China.

A Study on Microstructure and Mechanical Properties of TiC/Steel Composites Fabricated by Powder Metallurgy Process (분말야금공정으로 제조된 TiC/steel 금속복합재료의 미세조직 및 기계적 물성 연구)

  • Lee, Jihye;Cho, Seungchan;Kwon, Hansang;Lee, Sang-Kwan;Lee, Sang-Bok;Kim, Daeha;Kim, Junghwan
    • Composites Research
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    • v.34 no.5
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    • pp.311-316
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    • 2021
  • In this study, TiC/steel metal matrix composites were fabricated by powder metallurgy process using Fealloy powders with 3 wt.% Cr and 10 wt.% Cr, respectively, as matrix material. Subsequently, the composite samples were heat treated by the annealing and quenching-tempering(Q-T), respectively, to understand the effect of heat treatment on the mechanical properties of the composites. The correlation between microstructure and structural strength depending on the chromium content and the heat treatment conditions was studied through tensile, compressive, and transverse rupture test and microstructural analysis. In the case of TiC/steel composite containing 10 wt.% Cr, the tensile strength and transverse rupture strength at room temperature were significantly lowered by the influence of coarse chromium carbide formed at the TiC/steel interface. On the other hand, both TiC/steel composites containing 3 wt.% Cr and 10 wt.% Cr showed much higher compressive strength of about 4 GP after quenching-tempering compared to the annealed specimens regardless of the presence of the chromium carbide.

Identification of ecological characteristics of Deciduous broad-leaved forest, Garasan(Mt.)·Nojasan(Mt.) at GeoJae (거제도 가라산·노자산 일대 낙엽활엽수림의 생태적 특성 규명)

  • Lee, Soo-Dong;Cho, Bong-Gyo;Lee, Gyounggyu;Yeum, Jung-Hun;Oh, Chung-Hyeon
    • Korean Journal of Environment and Ecology
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    • v.35 no.2
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    • pp.204-219
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    • 2021
  • This study was conducted to investigate and analyze the characteristics of the plant community structure of vegetation distributed on the western slope and ridge connecting Mt. Noja to Mt. Gara. This basic research was executed not only to restore and manage forest vegetation, but also to monitor the trend of change in the long term. As a result of classifying the communitise in 86 survey quadrats, the Pinus thunbergii-Platycarya strobilacea comm. and P. thunbergii-P. densiflora comm. were distributed around the lowlands. The Carpinus tschonoskii-Deciduous broad-leaved comm., Styrax japonicus-Deciduous broad-leaved comm., Acer pictum subsp. Mono-Deciduous broad-leaved comm., Deciduous broad-leaved comm., and Zelkova serrata comm. appeared in the valley and all stone areas. Quercus serrata comm., Q. serrata-S. japonicus comm., S. japonicus-Carpinus cordata comm., Euonymus oxyphyllus comm. were classified as being distributed on steep slopes with relatively high altitude. According to the succession trend of the forest, evergreen conifers will be transition to deciduous broad-leaved trees. However, deciduous broad-leaved arboreous forests, such as Carpinus tschonoskii, zelkova serrata, and Acer pictum subsp. Mono, were considered to maintain their current succession stage because not only the stratified structure was developed over about 50 years tree age, but also ecologically stabilized. As environmental factors, it was analyzed that altitude, pH, content of clay and silt, Mg++, Ca++, etc. directly or indirectly affect the distribution of plant communities.

An Empirical Study on the Characteristics of Stock Returns in Chinese Stock Market -Focusing on the period of 1995 to 2007 - (중국 주식시장의 수익률 특성에 관한 실증연구 - 1995년부터 2007년 기간을 중심으로 -)

  • Kim, Kyung Won;Choi, Joon Hwan
    • International Area Studies Review
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    • v.13 no.3
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    • pp.287-308
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    • 2009
  • This article examines the distributional characteristics of the return of Chinese stock market indices. The majority of previous empirical researches have tended to focus upon the simple stock market index. However, this study focuses on the four indices which represent the characteristics of each stock market index. The empirical findings indicate that the returns of the four chinese indices are not normally distributed at conventional levels. The Ljimg-Box -statistics indicate the returns of the index of A shares are not serially autocorrelated. However, the returns of the index of B shares are serially autocorrelated. The empirical findings also indicate returns of the four chinese indices are not serially autocorrelated. The statistics of Regression Specification Error Test and ARCH indicate the returns of all four indices are not serially linear. The findings also indicate that E- GARCH model is the most fittest model for the returns of the four chinese indices and the forecast error can be reduced by using student t distribution rather normal distribution.

Exosomal miR-181b-5p Downregulation in Ascites Serves as a Potential Diagnostic Biomarker for Gastric Cancer-associated Malignant Ascites

  • Yun, Jieun;Han, Sang-Bae;Kim, Hong Jun;Go, Se-il;Lee, Won Sup;Bae, Woo Kyun;Cho, Sang-Hee;Song, Eun-Kee;Lee, Ok-Jun;Kim, Hee Kyung;Yang, Yaewon;Kwon, Jihyun;Chae, Hee Bok;Lee, Ki Hyeong;Han, Hye Sook
    • Journal of Gastric Cancer
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    • v.19 no.3
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    • pp.301-314
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    • 2019
  • Purpose: Peritoneal carcinomatosis in gastric cancer (GC) patients results in extremely poor prognosis. Malignant ascites samples are the most appropriate biological material to use to evaluate biomarkers for peritoneal carcinomatosis. This study identified exosomal MicroRNAs (miRNAs) differently expressed between benign liver cirrhosis-associated ascites (LC-ascites) and malignant gastric cancer-associated ascites (GC-ascites), and validated their role as diagnostic biomarkers for GC-ascites. Materials and Methods: Total RNA was extracted from exosomes isolated from 165 ascites samples (73 LC-ascites and 92 GC-ascites). Initially, microarrays were used to screen the expression levels of 2,006 miRNAs in the discovery cohort (n=22). Subsequently, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses were performed to validate the expression levels of selected exosomal miRNAs in the training (n=70) and validation (n=73) cohorts. Furthermore, carcinoembryonic antigen (CEA) levels were determined in ascites samples. Results: The miR-574-3p, miR-181b-5p, miR-4481, and miR-181d were significantly downregulated in the GC-ascites samples compared to the LC-ascites samples, and miR-181b-5p showed the best diagnostic performance for GC-ascites (area under the curve [AUC]=0.798 and 0.846 for the training and validation cohorts, respectively). The diagnostic performance of CEA for GC-ascites was improved by the combined analysis of miR-181b-5p and CEA (AUC=0.981 and 0.946 for the training and validation cohorts, respectively). Conclusions: We identified exosomal miRNAs capable of distinguishing between non-malignant and GC-ascites, showing that the combined use of miR-181b-5p and CEA could improve diagnosis.

TFAP2C Promotes Cell Proliferation by Upregulating CDC20 and TRIB3 in Non-small Cell Lung Cancer Cells (비소세포폐암 발달 과정에서 TFAP2C에 의해 발현되는 CDC20과 TRIB3의 원암유전자 기능에 관한 연구)

  • Kim, Dain;Do, Hyunhee;Kang, JiHoon;Youn, BuHyun;Kim, Wanyeon
    • Journal of Life Science
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    • v.29 no.6
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    • pp.645-652
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    • 2019
  • Non-small cell lung cancer (NSCLC) has the infamous distinction of being the leading cause of global cancer-related death over the past decade, and novel molecular targets are urgently required to change this status. We previously conducted a microarray analysis to investigate the association of transcription factor activating enhancer-binding protein 2C (TFAP2C) with NSCLC and revealed its oncogenic roles in NSCLC development. In this study, to identify new biomarkers for NSCLC, we focused on several oncogenes from the microarray analysis that are transcriptionally regulated by TFAP2C. Here, the cell division cycle 20 (CDC20) and tribbles pseudokinase 3 (TRIB3) were subsequently found as potential potent oncogenes as they are positively regulated by TFAP2C. The results showed that the mRNA and protein levels of CDC20 and TRIB3 were down-regulated in two NSCLC cell lines (NCI-H292 and NCI-H838), which were treated with TFAP2C siRNA, and that the overexpression of either CDC20 or TRIB3 was responsible for promoting cell viability in both NSCLC cell lines. In addition, apoptotic levels of NCI-H292 and NCI-H838 cells treated with TFAP2C siRNA were found to be suppressed by the overexpression of either CDC20 or TRIB3. Together, these results suggest that CDC20 and TRIB3 are positively related to NSCLC tumorigenesis and that they should be considered as potential prognostic markers for developing an NSCLC therapy.

Development of embedded type antenna structure with NFC and WPC complex function (NFC 와 WPC 복합기능의 삽입형 안테나 복합체 개발)

  • Park, Rog-gook;Lee, Deok-soo;Jang, Jeong-sun
    • Journal of Platform Technology
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    • v.6 no.4
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    • pp.59-68
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    • 2018
  • The objective of this study is to develop an embedded antenna structure with NFC and WPC composite functions. By selecting stable materials, the optimal component ratio of the polymer sheet was determined. The low cost embedded winding method compared to the existing FPCB was devised. During the winding process, characterization and process technology were developed. We also fabricated a ferrite mold to process the WPC grooves and developed the process technology for optimizing the WPC antenna. The following conclusions were obtained. (1) Optimum composition ratio was derived as Fe 87.5%, Si 7%, Al 5.5% and selected as the final material. (2) Optimal sheet conditions were derived from the experimental evaluation method and the experimental design method through the combination test of the optimized sheet and the conventional mass production FPCB. (3) According to coil diameter and inner diameter, Q value fluctuation, resistance value and efficiency fluctuation are obtained. Therefore, the most suitable coil condition is selected and Rx matching is performed. (4) The EMV load modulation test and the cognitive distance test of the polymer sheet and the ferrite sheet showed that the recognition distance of the polymer sheet at 1k and 4K was 32-33 mm and the recognition distance of the ferrite sheet at the same condition was 30-31 mm.

Growth of Candida albicans Biofilm is Inhibited by Salvia miltiorrhiza (단삼에 의한 Candida albicans 바이오필름 발달의 억제)

  • Lee, Heung-Shick;Kim, Younhee
    • Microbiology and Biotechnology Letters
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    • v.47 no.3
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    • pp.465-472
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    • 2019
  • Candida albicans is an opportunistic human pathogen that causes infections. Candidiasis is often related to antifungal resistance because the pathogen has the ability to form biofilms. In a previous study, we found that the Salvia miltiorriza ethanol extract demonstrated anticandidal activity by altering membrane permeability and inhibiting the cell wall synthesis in C. albicans. Our results here demonstrate that $78{\mu}g/ml$ of the S. miltiorriza extract significantly diminished the early stage biofilms formed by 10 clinical C. albicans isolates by 51.3%; this was analyzed by 2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide salt (XTT) reduction assay. The effect of the S. miltiorrhiza extract on the adhesion of C. albicans cells to polystyrene plates and germ tube formation was examined via microscopic investigation. Although the density of the adhered cells was remarkably reduced up on incubation with $39{\mu}g/ml$ S. miltiorrhiza extract, germ tube formation by C. albicans was rarely affected. Quantitative real-time PCR analysis showed that the S. miltiorrhiza extract downregulated the expression of C. albicans hypha-specific genes, EAP1 by 34.7% (p < 0.001), ALS1 by 45.0% (p < 0.001), ALS3 by 48.1% (p < 0.001), and ECE1 by 21.3% (p = 0.006), respectively. Our data suggest that the S. miltiorrhiza ethanol extract significantly inhibited the early stage of biofilm formation by C. albicans by interfering with cell adhesion, by downregulating EAP1, ALS1 and ALS3, and presumably by modifying the cell wall and membrane structure.