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๊ฐํ ์ถ์ถ๋ฌผ์ด ์ฌ๋ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ์ ๊ณจ๋ถํ์ ๋ฏธ์น๋ ์ํฅ
ํ์๋
ผ๋ฌธ (๋ฐ์ฌ) -- ์์ธ๋ํ๊ต ๋ํ์ : ์น์ํ๋ํ์ ์น์ํ๊ณผ, 2020. 8. ์ ํํ.Introduction: In the field of tissue engineering, dental stem cells isolated from human teeth have been differentiated into various cells in order to promote regeneration of tooth structures and periodontal tissue. Furthermore, many researches have been conducted to discover materials, especially natural products with fewer adverse side-effects or toxicity, that promote stem cell differentiation and periodontal tissue regeneration. Recently, implementation of naturally occurring bioactive compounds from seaweeds has been carried out for stimulating proliferation and differentiation of stem cells. In this study, Ecklonia cava, an edible brown alga species found along the southern coast of Korea, was investigated as a possible osteogenic product. Various biological activities of Ecklonia cava have been reported including antioxidation, anti-inflammatory, anticancer, antihypertensive, and antidiabetic effects. However, no previous study has investigated the effects of Ecklonia cava on the differentiation of human periodontal ligament stem cells (hPDLSCs). Thus, the aim of this study was to investigate the effects of Ecklonia cava on the osteogenic differentiation of hPDLSCs.
Materials and Methods: hPDLSCs were isolated and cultured from human third molars. To characterize the cultured hPDLSC, flow cytometric analysis was performed using mesenchymal stem cell (MSC) markers. Then, the multilineage differentiation capacity of hPDLSC was confirmed with Alizarin Red S stain, Oil Red O dye and Alcian Blue stain as indicators of osteogenic, adipogenic, and chondrogenic differentiation, respectively. To examine the effects of Ecklonia cava extract (ECE) on hPDLSC viability, hPDLSCs were incubated with various concentrations of ECE for 1, 3, and 7 days. Then, to investigate the effects of ECE on the osteogenic differentiation of hPDLSCs, gene expression levels of the osteoblastic marker genes, Col1, ALP, OPN, OCN, and Runx2, were examined by real-time PCR, and protein expression levels of OCN, OPN, Col1, and Runx2 were detected by Western blot. In addition, possible mechanism underlying the osteogenic differentiation process after ECE treatment was explored by measuring the expression levels of Smad4, p-Smad2/3, p-p38, p38, p-ERK1/2 and ERK1/2 using Western blot.
To evaluate the capacity of hPDLSCs for bone formation in response to ECE, hPDLSCs were mixed with HA/TCP without or with ECE and then subcutaneously transplanted into the dorsal surface of immunocompromised mice. For histological analysis, samples were acquired 10 weeks after transplantation, and hematoxylin and eosin (H&E) staining and immunohistochemical analysis were used to evaluate the differentiated bone-like tissue.
Results: Characterization of hPDLSCs as mesenchymal stem cells (MSCs) and multilineage differentiation potential of hPDLSCs were confirmed. For the effects of ECE on hPDLSC proliferation, ECE increased proliferation of hPDLSCs without any cytotoxicity after 1 and 3 days of culture. After 7 days of culture, cell proliferation declined below the control value starting at 100 ยตg/ml of ECE. Real-time PCR showed that expressions of ALP, Col1, OCN, OPN, and Runx2 increased in ECE-treated group compared to untreated group, and protein expression levels of OCN, OPN, Col1, and Runx2 increased as well. In addition, Western blot analysis demonstrated that ECE may stimulate osteogenesis by activation of p38 and ERK1/2 signaling pathways.
For in vivo study, histological analysis with H&E staining showed increased area of bone-like tissue layer in the ECE-treated group, and immunohistochemical analysis confirmed the generation of bone-like tissue with increased OSX, OPN, and OCN expressions.
Conclusion: In this study, the effect of ECE on osteogenic differentiation of hPDLSCs was investigated in vitro and in vivo. The results of the experiments confirmed that ECE-treated group had greater ability to promote osteogenic differentiation of hPDLSCs compared to the control group. Therefore, ECE is suggested to be a potential natural compound with therapeutic properties against bone-related complications and diseases that urge further studies to elucidate its detailed mechanism of action and bioavailability.์น์์ ์ฌ๋ฌ ๋ถ์์์ ์ค๊ธฐ์ธํฌ๋ฅผ ์ถ์ถํ์ฌ ๋ค์ํ ์ธํฌ๋ก ๋ถํ์ํค๊ณ ์ด๋ฅผ ์ด์ฉํ ์น์ ๋ฐ ์น์ฃผ์กฐ์ง์ ์ฌ์์ ๋ํ ์ฐ๊ตฌ๊ฐ ๋ง์ด ์งํ๋์ด ์๋ค. ๋ ๋์๊ฐ ์ค๊ธฐ์ธํฌ์ ๋ถํ ๋ฐ ์น์ฃผ์กฐ์ง์ ์ฌ์์ ์ด์งํ๋ ์ธ์๋ค, ํนํ ๋ถ์์ฉ์ด๋ ๋
์ฑ์ด ์ ์ ์ฒ์ฐ๋ฌผ์ ๋ํ ์ฐ๊ตฌ๋ ํ๋ฐํ๊ฒ ์ด๋ฃจ์ด์ง๊ณ ์๋ค. ๋ณธ ์ฐ๊ตฌ์์ ์ฌ์ฉํ ๊ฐํ๋ ๋ค์๋ง๋ชฉ ๋ฏธ์ญ๊ณผ์ ๊ฐ์กฐ๋ฅ๋ก ์ฐ๋ฆฌ๋๋ผ ๋ํด์๊ณผ ์ ์ฃผ๋ ๊ทผํด์ ๋๋ฆฌ ์์ํ๊ณ ์๋ค. ํ์ฌ๊น์ง ๋ณด๊ณ ๋ ๊ฐํ์ ๋ํ ์ฐ๊ตฌ๋ก๋ ํญ์ฐํ, ํญ์ผ์ฆ, ํญ์, ํญ๊ณ ํ์ ๋ฐ ํญ๋น๋จ ํจ๋ฅ ๋ฑ์ด ๋ณด๊ณ ๋์ด์์ง๋ง ์ฌ๋์น์์ค๊ธฐ์ธํฌ์ ๋ฏธ์น๋ ์ํฅ์ ๋ํ ์ฐ๊ตฌ๋ ์ด๋ฃจ์ด์ง ๋ฐ๊ฐ ์์ด ๋ณธ ์ฐ๊ตฌ์์๋ ๊ฐํ ์ถ์ถ๋ฌผ์ด ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ์ ์ด๋ ํ ์ํฅ์ ์ฃผ๋์ง ์์๋ณด๊ณ ์ ํ๋ค.
์ฑ์ธ ๋ฏธ์ฑ์ ์ 3๋๊ตฌ์น๋ก๋ถํฐ ์ถ์ถํ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ๋ฅผ ๋ฐฐ์ํ ๋ค ์ค๊ฐ์ฝ ์ค๊ธฐ์ธํฌ์ ํ์ง์ ํ์ธ์ ์ํด ์ ์ธํฌ๋ถ์๋ฒ์ ์ํํ์๋ค. ์ถ์ถ๋ ์ธํฌ๋ฅผ ๊ณจ์์ธํฌ, ์ง๋ฐฉ์ธํฌ, ์ฐ๊ณจ์ธํฌ๋ก ๋ถํ์ํจ ํ ๊ฐ๊ฐ์ ์ผ์์ ์ํํ์ฌ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ์ ๋ค๋ถํ๋ฅ๋ ฅ์ ํ์ธํ์๋ค. ์ธํฌ ์ฆ์ ๋ฐ ๋
์ฑ์ ๋ํ ์ํฅ์ ์กฐ์ฌํ๊ธฐ ์ํ์ฌ ๊ฐํ ์ถ์ถ๋ฌผ์ ๋๋๋ณ๋ก ์ฒ๋ฆฌํ์ฌ 1์ผ, 3์ผ ๋ฐ 7์ผ ๋์ ๋ฐฐ์ํ ํ ์ธํฌ ์์กด๋ฅ ๋ถ์์ ์ํํ์๋ค. ์ ์ ๊ฐํ ์ถ์ถ๋ฌผ์ ๋๋๋ฅผ ํ์ธํ ํ ๊ณจ๋ถํ๊ฐ ์ ๋๋ ์ธํฌ๋ฅผ ๋์์ผ๋ก quantitative RT-PCR์ ํตํด ์กฐ๊ณจ์ธํฌ ๋ถํ ์ ์ ์์ธ Col1, ALP, OPN, OCN ๋ฐ Runx2์ ๋ฐํ ์ ๋ ๋ฐ Western blot์ผ๋ก OCN, OPN, Col1 ๋ฐ Runx2 ๋จ๋ฐฑ์ง ๋ฐํ ์ ๋๋ฅผ ํ์ธํ์๋ค. ๋ํ Western blot์ผ๋ก Smad4, p-Smad2/3, p-38, p38, p-ERK1/2 ๋ฐ ERK1/2์ ๋ฐํ ์ ๋๋ฅผ ์ธก์ ํจ์ผ๋ก์จ ๊ฐํ ์ถ์ถ๋ฌผ ์ฒ๋ฆฌ ํ ๊ณจํ์ฑ ๋ถํ ๊ณผ์ ์ ๊ธฐ๋ณธ์ด ๋๋ ๋ฉ์ปค๋์ฆ์ ์กฐ์ฌํ์๋ค. ์ฒด๋ด์์์ ๋ถํ๋ฅผ ํ์ธํ๊ธฐ ์ํด ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ๋ฅผ HA/TCP์ ํผํฉํ์ฌ ๋ฉด์ญ ์ต์ ๋ ์ฅ์ ๋ฑ์ 10์ฃผ ๋์ ์ด์ํ์๋ค. ๊ฐํ ์ถ์ถ๋ฌผ์ ์ํ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ์ ๊ณจ๋ถํ๋ฅผ ์กฐ์ฌํ๊ธฐ ์ํด ์กฐ์งํ์ ๋ถ์๊ณผ ๋ฉด์ญ์กฐ์งํํ๋ฒ์ ์ด์ฉํ ๋ถ์์ ์ํํ์๋ค.
์ ์ธํฌ๋ถ์๋ฒ์ ํตํด ์ฑ์ธ ๋ฏธ์ฑ์ ์ 3๋๊ตฌ์น๋ก๋ถํฐ ์ถ์ถํ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ๊ฐ ์ค๊ฐ์ฝ ์ ๋ ์ค๊ธฐ์ธํฌ์ ํน์ง์ ๊ฐ๊ณ ์๊ณ ๋ํ Alizarin Red S ์ผ์, Alcian Blue ์ผ์, Oil Red O ์ผ์์ ํตํด ๊ณจ์กฐ์ง, ์ฐ๊ณจ์กฐ์ง, ์ง๋ฐฉ์กฐ์ง์ผ๋ก ๋ถํ๊ฐ ๊ฐ๋ฅํ ๊ฒ์ ํ์ธํ์๋ค. ๊ฐํ ์ถ์ถ๋ฌผ์ ๋๋๋ณ๋ก ์ฒ๋ฆฌํ์์ ๋ ๋ฐฐ์ 1์ผ ๋ฐ 3์ผ ํ์๋ ์ธํฌ ๋
์ฑ์ด ๋ํ๋์ง ์์์ผ๋ฉฐ ๋ฐฐ์ 7์ผ์์๋ 100 ฮผg/ml ๋๋๋ถํฐ ์ธํฌ ๋
์ฑ์ด ๋ํ๋๋ ๊ฒ์ผ๋ก ๊ด์ฐฐ๋์๋ค. Quantitative RT-PCR์ ํตํด ๊ฐํ ์ถ์ถ๋ฌผ ์ฒ๋ฆฌ๊ตฐ์์ ALP, Col1, OCN, OPN ๋ฐ Runx2์ ๋ฐํ์ด ์ฒ๋ฆฌ๋์ง ์์ ๊ตฐ์ ๋นํด ์ฆ๊ฐํ๊ณ , OCN, OPN, Col1 ๋ฐ Runx2์ ๋จ๋ฐฑ์ง ๋ฐํ๋ ์ฆ๊ฐํจ์ ๋ณด์ฌ ์ฃผ์๋ค. ๋ํ, Western blot ๋ถ์์ ๊ฐํ ์ถ์ถ๋ฌผ์ด p38 ๋ฐ ERK1/2 ์ ํธ ๊ฒฝ๋ก์ ํ์ฑํ์ ์ํด ๊ณจํ์ฑ์ ์ ๋ ํ ์ ์์์ ์
์ฆ ํ์๋ค.๋ฉด์ญ ์ต์ ๋ ์ฅ๋ฅผ ์ด์ฉํ ์์ฒด๋ด ์คํ์์ H&E ์ผ์์ ์ฌ์ฉํ ์กฐ์งํ์ ๋ถ์์ ๊ฐํ ์ถ์ถ๋ฌผ ์ฒ๋ฆฌ ๊ตฐ์์ ๋ผ-์ ์ฌ ์กฐ์ง์ธต์ ๋ฉด์ ์ด ์ฆ๊ฐํ ๊ฒ์ผ๋ก ๋ํ๋ฌ๊ณ , ๋ฉด์ญ์กฐ์งํํ ๋ถ์์ OSX, OPN ๋ฐ OCN ๋ฐํ์ ์ฆ๊ฐ๋ก ๋ผ-์ ์ฌ ์กฐ์ง์ ์์ฑ์ ํ์ธํ์๋ค.
๋ณธ ์ฐ๊ตฌ์์๋ ์์ฒด์ธ ๋ฐ ์์ฒด๋ด ์คํ์ ํตํ์ฌ ๊ฐํ ์ถ์ถ๋ฌผ์ด ์ฌ๋ ์น์ฃผ์ธ๋ ์ค๊ธฐ์ธํฌ์ ๊ณจ๋ถํ๋ฅผ ์ด์งํ๋ ๊ฒ์ ํ์ธํ์๋ค. ๊ฒฐ๋ก ์ ์ผ๋ก ์ด ์คํ์ ์์์ ์๋ฏธ๋ ๊ฐํ ์ถ์ถ๋ฌผ์ ์น์กฐ๊ณจ ์ฌ์์ ํจ๊ณผ์ ์ธ ์ํฅ์ ๋ฏธ์น ๊ฒ์ผ๋ก ์ฌ๋ฃ๋๋ฉฐ ํฅํ ๊ฐํ ์ถ์ถ๋ฌผ์ ์ ํํ ์์ฉ๊ธฐ์ ๋ฐ ์์ฒด ์ด์ฉ๋ฅ ์ ๋ฐํ๊ธฐ ์ํ ์ถ๊ฐ ์ฐ๊ตฌ๊ฐ ํ์ํ ๊ฒ์ผ๋ก ์๊ฐ๋๋ค.I. Introduction 1
II. Materials and Methods 5
III. Results 14
IV. Discussion 18
V. Conclusion 25
References 26
Table 34
Figures 35
Abstract in Korean 45Docto
Effects of Divergent Thinking Training/Instructions on Torrance Tests of Creative Thinking and Creative Performance
Using a quasi-experimental design, with pretest and posttest measures with multiple probes, the effects of divergent thinking training (with explicit instruction) on creative worksheets, the Torrance Tests of Creative Thinking (TTCT; Torrance, 1990) and story-based problem solving tasks (Realistic Story Telling Problems Activity) were investigated. Explicit instructions for originality enhanced the originality scores on figural creative worksheets and explicit instructions for fluency enhanced the fluency scores on both figural and verbal creative worksheets for experimental group members (n = 15). In addition, experimental group members made significant gains on originality scores on the TTCT (p. \u3c .05), Problem Solving (p. \u3c .05) tasks from the Realistic Story Telling Problems, fluency scores on the TTCT (p. \u3c .001), and Problem Identification (p. \u3c .05) and Problem Solving (p. \u3c .05) tasks from Realistic Story Telling Problems; control group members (n = 15) did not. Implications of the findings of this study are discussed
The effect of computer-mediated communication (CMC) interaction on L2 vocabulary acquisition: A comparison study of CMC interaction and face-to-face interaction
This study investigates the differential effects of CMC interaction (both text-chat and voice-chat) and face-to-face interactions on university level of ESL students\u27 vocabulary acquisition. More specifically, this study examines (a) whether learners engage in negotiated interaction when they encounter new lexical items, (b) whether CMC interaction help learners acquire new lexical items productively, (c) whether there are any special features related to negotiation routines in the most acquired words and the least acquired words, and (d) whether ESL students find CMC interaction helpful for their English learning. The participants consisted of 12 (6 male, 6 female) international students and visiting scholars at Iowa State University. The research design included a pre-test, a treatment activity, an immediate post-test, and a 1 week delayed post-test. The pre-test containing 24 vocabulary whose referents were auto parts items was given to choose the target lexical items. The type of treatment activity used in this study was an information-gap activity in which the students were required to request and obtain information from each other to complete the task. Two post-tests (immediate and delayed) were administered to assess the acquisition of new lexical items. The immediate and delayed post-tests were offered to students on the treatment day and 1 week after the initial treatment. Finally, a follow-up survey from each participant in CMC interaction group was also used to determine the strengths and weaknesses of computer-assisted language learning (CALL) task and the drawbacks or advantages of using such activities for language learning. The results showed that all ESL learners in both CMC and face-to-face interaction negotiated to complete their tasks, and all of the twelve target lexical items prompted negotiation for all of the dyads. Moreover, the results revealed that the students in all three groups recalled more than half of the previously unknown target lexical items in the immediate post-test and delayed post-test. For both productive oral and written acquisition, the results revealed that all three conditions seem to facilitate the acquisition of L2 words, as well as to ensure a good level of retention. However, there were no statistically significant differences between groups and posttests. Thus, meaning negotiation during computer-mediated and face-to-face interaction seems to promote both oral and written acquisition of L2 vocabulary. In addition, the results indicated that students tended to acquire new lexical items when they had some background knowledge about the target words or they were negotiating both form and meaning with their partners. A follow-up survey data showed that most of the students in both text-chat and voice-chat CMC interaction group had a positive attitude towards this type of activity in online, and they found synchronous chat as an interesting and helpful way of English learning
On the linear convergence of additive Schwarz methods for the -Laplacian
We consider additive Schwarz methods for boundary value problems involving
the -Laplacian. While the existing theoretical estimates for the convergence
rate of additive Schwarz methods for the -Laplacian are sublinear, the
actual convergence rate observed by numerical experiments is linear. In this
paper, we bridge the gap between these theoretical and numerical results by
analyzing the linear convergence rate of additive Schwarz methods for the
-Laplacian. In order to estimate the linear convergence rate of the methods,
we present two essential components. Firstly, we present a new abstract
convergence theory of additive Schwarz methods written in terms of a
quasi-norm. This quasi-norm exhibits behavior similar to the Bregman distance
of the convex energy functional associated to the problem. Secondly, we provide
a quasi-norm version of the Poincar'{e}--Friedrichs inequality, which is
essential for deriving a quasi-norm stable decomposition for a two-level domain
decomposition setting.Comment: 23 pages, 2 figure
Numerical analysis of high-index nanocomposite encapsulant for light-emitting diodes
We used two-dimensional Finte-Difference-Time-Domain (FDTD) software to study
the transition behavior of nano-particles from scatterers to an optically
uniform medium. We measured the transmission efficiency of the dipole source,
which is located in the high refractive index medium(index=2.00) and
encapsulated by low index resin(index=1.41). In an effort to compose
index-matched resin and to reduce internal reflection, high-index
nano-particles are added to low-index resin in simulations of various sizes and
densities. As the size of the nano-particles and the average spacing between
particles are reduced to 0.02 lambda and 0.07 lambda respectively, the
transmission efficiency improves two-fold compared to that without
nanoparticles. The numerical results can be used to understand the optical
behavior of nano-particles and to improve the extraction efficiency of high
brightness light-emitting-diodes(LEDs), through the use of nano-composite
encapsulant.Comment: 9 pages, 5 jpg figure
Optimisation of pipeline route in the presence of obstacles based on a least cost path algorithm and laplacian smoothing
Subsea pipeline route design is a crucial task for the offshore oil and gas industry, and the route selected can significantly affect the success or failure of an offshore project. Thus, it is essential to design pipeline routes to be eco-friendly, economical and safe. Obstacle avoidance is one of the main problems that affect pipeline route selection. In this study, we propose a technique for designing an automatic obstacle avoidance. The Laplacian smoothing algorithm was used to make automatically generated pipeline routes fairer. The algorithms were fast and the method was shown to be effective and easy to use in a simple set of case studies
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