• Title/Summary/Keyword: Development factor

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The Investigation of Cell Culture Conditions to Maintain Chicken Embryonic Stem Cells as Totipotent Cells

  • Du, Lixin;An, Jing
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.8
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    • pp.1102-1107
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    • 2003
  • The ES cell can provide a useful system for studying differentiation and development in vitro and a powerful tool for producing transgenic animalds. To investigate the culture condition of chicken embryonic stem (CES) cells which can retain their multipotentiality or totipotency, three kinds of feeder layer cells, SNL cells, primary mice embryonic fibroblasts (PMEF) cells and primary chicken embryonic fibroblasts (PCEF) cells, were used as the feeder cells in media of DMEM supplemented with leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and stem cell factor (SCF) for co-culture with blastoderm cells from stage X embryos of chicken. The alkaline phosphatase (AKP) test, differentiation experiment in vitro and chimeric chicken production were carried out. The results showed that culture on feeder layer of PMEF yielded high quality CES cell colonies. The typical CES cells clone shape revealed as follows: nested aggregation (clone) with clear edge and round surface as well as close arrangement within the clone. Strong alkaline phosphatase (AKP) reactive cells were observed in the fourth passage cells. On the other hand, the fourth passage CES cells could differentiate into various cells in the absence of feeder layer cells and LIF in vitro. The third and fourth passage cells were injected into the subgerminal cavity of recipient embryos at stage X. Of 269 Hailan embryos injected with CES cells of Shouguang Chickens, 8.2% (22/269) survived to hatching, 5 feather chimeras had been produced. This suggests that an effective culture system established in this study can promote the growth of CES cells and maintain them in the state of undifferentiated and development, which lays a solid foundation for the application of CES cells and may provide an alternative tool for genetic modification of chickens.

Differences of Appearance Management Behaviors among Appearance Management Motives (외모관리동기에 따른 외모관리행동의 차이에 관한 연구)

  • Kim, Insuk
    • Fashion & Textile Research Journal
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    • v.19 no.4
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    • pp.468-478
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    • 2017
  • The purpose of this study is to examine the differences in appearance management behaviors and demographic variables among groups classified by the appearance management motives. The questionaries are administerd to 493 female and male adults above 20 years old in Seoul, Kyeonggi-do, Daegu and Kyungpook regions. For analysis of data from 478 respondents, descriptive statistics, factor analysis, cluster analysis, Cronbach's ${\alpha}$, ANOVA, Duncan test and ${\chi}^2$ test were applied. We show the following results: First, factor analysis for appearance management motives extracted three factors such as self-development, emphasis on the trendy appearance, and sexual appealing motive. Factor analysis for appearance management behaviors extracted four factors such as weight training, surgery/skin care, hair care and clothing selection. Second, three groups of the appearance management motives were classified into such as the social self-management type, the sexual appealing self-management type, the passive appearance management type. The social self-management groups are more interested in self-development, emphasis on the trendy appearance, and sexual appealing motive. And they are also more involved in appearance management behaviors: clothing selection is the most pursuing appearance management behavior. Third, among the demographic variables, the single and female in 20s and 30s with higher level of education belonged to the social self-management group. In this contribution, we find significant differences in the appearance management behavior and demographic variables classified by the appearance management motives.

Relationship self-perceived halitosis and related factor among adults (성인의 구취 자각도 실태와 관련요인)

  • Cho, Hye-Eun
    • Journal of Korean society of Dental Hygiene
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    • v.17 no.6
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    • pp.1121-1134
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    • 2017
  • Objectives: The purpose of this study is to analyze the factors affecting the self-perceived halitosis of adults and to utilize them as basic data for the development of prevention and management program to reduce of self-perceived halitosis. Methods: A questionnaire survey of 301 adults in their 20s and 50s living in Gwangju and Jeonnam selected by convenience sampling from July 1, 2017 to August 31, 2017 was conducted to investigate oral health status and behavior, fatigue and perceived stress. Statistical analysis was performed using frequency analysis, independent t-test, one way ANOVA, Pearson's correlation analysis, and multiple regression analysis. Results: The degree of self-perceived halitosis was higher in married (2.51) and unemployed (2.71), with tongue brushing (2.68), intention to participate in halitosis education (2.57), taking medication (2.73), coated tongue (2.82) and there was both otolaryngology and gastrointestinal disease (2.72) and periodontal disease (2.89) (p<0.05). Fatigue (${\beta}=0.237$), periodontal disease (${\beta}=0.196$), and coated tongue (${\beta}=0.237$) affect the self-perceived halitosis (p<0.001). Conclusions: The self-perceived halitosis in adults was correlated with fatigue and perceived stress. Also fatigue, periodontal disease, coated tongue factors were analyzed as factors influencing self-perceived halitosis. Additional studies such as prevention and management of periodontal disease and coated tongue, which is a factor of self-perceived halitosis in adults, and development of programs to reduce self-perceived halitosis for fatigue management, which is an external factor, are necessary.

Determination of Priority in Installing Road in Farming and Fishing Communities by Using GIS & Statistical Analysis Techniques (농어촌도로 개발 우선순위 결정을 위한 GIS와 통계분석기법의 활용)

  • Kim, Dong-Moon;Lee, Sang-Yeun;Park, Byung-Soo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.4
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    • pp.351-358
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    • 2006
  • The farming and fishing village roads is located in a mountainous geographical feature, a resident's movement zone is followed by many restrictions in economic activities or social activities. Establishment of general planning gets into guide of long-term development direction for road in farming and fishing villages area. This study examined and analyzed a regional characteristics such as a regional environment and traffic condition, etc. and an actual condition of farming and fishing village roads, selected a factor affecting a priority to open a road, calculated a weight per each factor by AHP & Statistical analysis techniques, converted it into GIS database, and determined a priority for paying forming and fishing village roads. It is that development precedence and estimation calculation are decided applying result of research, GIS and AHP and statistical processing techniques.

A Study on Rotary Weeding Blade Installation Angle for Reduction of Hand Vibration in Working Type Cultivator

  • Kwon, Tae Hyeong;Kim, Joonyong;Lee, Chungu;Kang, Tae Gyoung;Lee, Byeong-Mo;Rhee, Joong-Yong
    • Journal of Biosystems Engineering
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    • v.39 no.1
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    • pp.11-20
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    • 2014
  • Purpose: Walking type cultivator used for weeding generated excessive handle vibration as well as bouncing motion depending on the weeding speed. This research was conducted to define a design factor of the rotary weeding blades for reducing soil reaction forces as well as hand vibration. Methods: The motion and forces acting on the rotary blades were reviewed to find out the most influencing parameter on hand vibration. The installation angle (IA) of the blade was selected and analyzed to determine the condition of no reaction force less. For removing the unnecessary upward soil reaction, the design factor theory of weeding blade was suggested based on geometrics and dynamics. For evaluation of design factor theory, the experiment in situ was performed base on ISO 5349:1. The vibration $a_{hv}$ and theoretical value $X_{MF}$ were compared with two groups that one was positive group ($X_{MF}$ > 0) and the other was negative group ($X_{MF}$ < 0). Results: $X_{MF}$ was derived from rotational velocity, forward velocity, disk diameter, weeding depth, blade's width and IA of blade. Two groups had significant difference (p < 0.05). In aspect of the group mean total exposure duration, positive group was 17.53% bigger than negative group. When disk radius 100, 150 and 200 mm, minimum IAs were $4{\sim}27^{\circ}$, $3{\sim}15^{\circ}$ and $2{\sim}10^{\circ}$, respectively. A spread sheet program which calculated XMF was developed by Excel 2013. Conclusions: According to this result, minimum IA of weeding blade for soil reaction reduction could be obtained. For reduction hand-arm vibration and power consumption, minimum IA is needed.

A Study on the Development of User Experience Indicators for The Knowledge and Information Resource System (지식정보자원시스템 이용자 경험 지표개발에 관한 연구)

  • Chun, Jung Hyun;Lee, Jee Yeon
    • Journal of the Korean Society for Library and Information Science
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    • v.54 no.3
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    • pp.209-236
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    • 2020
  • This study describes a set of user experience indicators developed for the evaluation of knowledge and information resource systems. The user experience perspectives had emerged as a new analysis standard in the field of information media and information service research. The study included a survey conducted to verify the derived experience factors and developed them as indicators. The survey data was gathered from 158 participants in the preliminary and 480 participants in the main study. The applied analysis techniques were descriptive statistics, the exploratory factor analysis, the confirmatory factor analysis, the correlation analysis, and the path analysis. The results introduced seven user experience factors, 37 detailed user experience factors, and 105 system perception factors as the final user experience indicators. The developed and verified indicators should measure the degree of user experience perceived by users of the knowledge and information resource system and conduct effective evaluations that reflect correlation rather than a simple comparison of each experience factor.

Angiotensin II Promotes Smooth Muscle Cell Proliferation and Migration through Release of Heparin-binding Epidermal Growth Factor and Activation of EGF-Receptor Pathway

  • Yang, Xiaoping;Zhu, Mei J.;Sreejayan, N.;Ren, J.;Du, Min
    • Molecules and Cells
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    • v.20 no.2
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    • pp.263-270
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    • 2005
  • Transactivation of EGF-receptor (EGFR) by G-protein coupled receptors (GPCRs) is emerging as an important pathway in cell proliferation, which plays a crucial role in the development of atherosclerotic lesion. Angiotensin II (Ang II) has been identified to have a major role in the formation of atherosclerotic lesions, although the underlying mechanisms remain largely unclear. We hypothesize that Ang II promotes the proliferation and migration of smooth muscle cells through the release of heparin-binding epidermal growth factor like growth factor (HB-EGF), transactivation of EGFR and activation of Akt and Erk 1/2, with matrix metalloproteases (MMPs) playing a dispensable role. Primary rat aortic smooth muscle cells were used in this study. Smooth muscle cells rendered quiescent by serum deprivation for 12 h were treated with Ang II (100 nM) in the presence of either GM6001 ($20{\mu}M$), a specific inhibitor of MMPs or AG1478 ($10{\mu}M$), an inhibitor of EGFR. The levels of phosphorylation of EGFR, Akt and Erk 1/2 were assessed in the cell lysates. Inhibition of MMPs by GM6001 significantly attenuated Ang II-stimulated phosphorylation of EGFR, suggesting that MMPs may be involved in the transactivation of EGFR by Ang II receptor. Furthermore Ang II-stimulated proliferation and migration of smooth muscle cells were significantly blunted by inhibiting MMPs and EGFR and applying HB-EGF neutralization antibody, indicating that MMPs, HB-EGF and EGFR activation is necessary for Ang-II stimulated migration and proliferation of smooth muscle cells. Our results suggest that inhibition of MMPs may represent one of the strategies to counter the mitogenic and motogenic effects of Ang II on smooth muscle cells and thereby prevent the formation and development of atherosclerotic lesions.

Interpretation of Animal Dose and Human Equivalent Dose for Drug Development

  • Shin, Jang-Woo;Seol, In-Chan;Son, Chang-Gue
    • The Journal of Korean Medicine
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    • v.31 no.3
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    • pp.1-7
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    • 2010
  • Objectives: To introduce to TKM scientific dose conversion methods of human to animal or animal to human for new drug investigations. Methods: We searched guidelines of the FDA and KFDA, and compared them with references for drug-dose conversion from various databases such as PubMed and Google. Then, we analyzed the potential issues and problems related to dose conversion in safety documentation of new herbal drugs based on our experiences during Investigational New Drug (IND) applications of TKM. Results: Dose conversion from human to animal or animal to human must be appropriately translated during new drug development. From time to time, investigators have some difficulty in determining the appropriate dose, because of misunderstandings of dose conversion, especially when they estimate starting dose in clinical or animal studies to investigate efficacy, toxicology and mechanisms. Therefore, education of appropriate dose calculation is crucial for investigators. The animal dose should not be extrapolated to humans by a simple conversion method based only on body weight, because many studies suggest the normalization method is based mainly on body surface area (BSA). In general, the body surface area seems to have good correlation among species with several parameters including oxygen utilization, caloric expenditure, basal metabolism, blood volume and circulating plasma protein. Likewise, a safety factor should be taken into consideration when deciding high dose in animal toxicology study. Conclusion: Herein, we explain the significance of dose conversion based on body surface area and starting dose estimation for clinical trials with safety factor.

Effects of Physical Characteristics on a Nutrient-Chlorophyll Relationship in Korean Reservoirs

  • Hwang, Soon-Jin;Jeon, Ji-Hong;Ham, Jong-Hwa;Kim, Ho-Sub
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.7
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    • pp.64-73
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    • 2002
  • This study was performed to evaluate effects of physical characteristics of both watershed and reservoir on nutrient-chlorophyll relationship in Korean reservoirs. Simple linear models were developed with published data in Korea including 415 reservoirs and 11 multi-purpose dams, and physico-chemical parameters of reservoirs and characteristics relationship of models were analyzed. Theoretical residence time in Korean reservoirs was strongly correlated with the ratio of TA/ST (drainage area + surface area / storage volume) in the logarithmic function. As a result of monthly nutrients-chlorophyll-a regression analysis, significant Chl-a-TP relationship appeared during May~July. The high Chl-a yields per total phosphorus appeared during this time (R$\^$2/=0.51, p<0.001, N= 1088). Chlorophyll-a demonstrated much stronger relationship with TP. than TN. Seasonal algal-nutrient coupling were closely related with N:P ratio in the reservoir water, and it was, in turn, dependent on the monsoon climatic condition (precipitation). Based on the results of regression analysis and high N:P ratio, a major limiting factor of algal growth appeared to be phosphorus during this time. Unlikely TA/ST ratio, DA/SA ratio (drainage area f surface area) was likely to influence directly on the nutrient-Chl-a relationship, indicating that if storage volume and inflowing water volume were the same, algal biomass could be developed more in reservoirs with large surface area. Thus, DA/SA ratio seemed to be an important factor to affect the development of algal biomass in Korean reservoirs. With low determination coefficient of TP-Chl-a relationship, our findings indicated not only nutrient (phosphorus) but also other physical factors, such as DA/SA ratio, may affect algal biomass development in Korean reservoirs, where actual residence time appears to be more closely related to reservoir surface area rather than storage volume.

Murrayafoline A Induces a G0/G1-Phase Arrest in Platelet-Derived Growth Factor-Stimulated Vascular Smooth Muscle Cells

  • Han, Joo-Hui;Kim, Yohan;Jung, Sang-Hyuk;Lee, Jung-Jin;Park, Hyun-Soo;Song, Gyu-Yong;Nguyen, Manh Cuong;Kim, Young Ho;Myung, Chang-Seon
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.5
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    • pp.421-426
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    • 2015
  • The increased potential for vascular smooth muscle cell (VSMC) growth is a key abnormality in the development of atherosclerosis and post-angioplasty restenosis. Abnormally high activity of platelet-derived growth factor (PDGF) is believed to play a central role in the etiology of these pathophysiological situations. Here, we investigated the anti-proliferative effects and possible mechanism(s) of murrayafoline A, a carbazole alkaloid isolated from Glycosmis stenocarpa Guillamin (Rutaceae), on PDGF-BB-stimulated VSMCs. Murrayafoline A inhibited the PDGF-BB-stimulated proliferation of VSMCs in a concentration-dependent manner, as measured using a non-radioactive colorimetric WST-1 assay and direct cell counting. Furthermore, murrayafoline A suppressed the PDGF-BB-stimulated progression through $G_0/G_1$ to S phase of the cell cycle, as measured by [$^3H$]-thymidine incorporation assay and cell cycle progression analysis. This anti-proliferative action of murrayafoline A, arresting cell cycle progression at $G_0/G_1$ phase in PDGF-BB-stimulated VSMCs, was mediated via down-regulation of the expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, and proliferating cell nuclear antigen (PCNA), and the phosphorylation of retinoblastoma protein (pRb). These results indicate that murrayafoline A may be useful in preventing the progression of vascular complications such as restenosis after percutaneous transluminal coronary angioplasty and atherosclerosis.