39 research outputs found
์๋์ ํ๊ธ ํด๋ ์์ค์ ๋ฐ๋ฅธ ๋น๊ต
ํ์๋
ผ๋ฌธ(์์ฌ) -- ์์ธ๋ํ๊ต๋ํ์ : ์ฌ๋ฒ๋ํ ํ๋๊ณผ์ ์ ์๊ต์ก์ ๊ณต, 2023. 2. ์ต๋์ผ.The aim of this study is to investigate the Hangeul acquisition levels of 5-year-old children and children in the first grade of the Korean education system, and to compare how the teachers of the aforementioned children and their parents differ in their opinions toward literacy guidance and Intensive Hangeul Education Policy (IHEP), a policy sponsored by the Korean ministry of education. In order to complete such tasks, the study examined whether or not the Hangeul acquisition level of children who are in the transitional period between kindergarten and elementary school showed any correlation with the way in which teachers and parents view literacy guidance and IHEP, and the differences between the four groups were compared based on their attitudes toward literacy guidance and the IHEP.
Samples were collected from the Seoul metropolitan area in Korea and included the following: 156 5-year-old class kindergarten teachers, 177 parents of the 5-year-old children, 155 grade 1 elementary school teachers, and 184 parents of the 1st graders, which amounts to 4 distinct groups and 672 samples total. The participants were asked to record their responses on an online questionnaire, answering questions about the childrens Hangeul acquisition levels, literacy guidance (emergent and conventional), and IHEP (awareness, understanding of the program and its benefits, and openness).
Regarding the Hangeul acquisition level, the teachers recorded their responses based on the mean level of Hangeul acquisition amongst their students, and parents responded in accordance with the level of Hangeul acquisition of their children. The collected data were analyzed using the SPSS Statistics 26.0 package, and descriptive statistics, independent sample t-test, one-way analysis of variance, and Scheffรฉs test.
The major finding of the study are as follows:
First, according to the data collected from the teachers and the parents, the Hangeul acquisition level of first graders was statistically higher than that of 5 year olds. However, the 5 year olds also scored high on the Hangeul acquisition level, and there were first graders who scored low on the level.
Second, depending on the level (highยทmiddleยทlow) of a childs Hangeul acquisition level, there was a difference in how each of the aforementioned sample groups perceived literacy guidance and IHEP. As for the parents of 5 year olds and first graders, both groups showed that when a child belongs to the high level group, they gave more literacyโboth emergent and conventionalโguidance to the child. The kindergarten teachers, on the other hand, did not show any significant differences in emergent literacy guidance. They, however, did give more conventional literacy guidance to the high level children. The elementary school teachers exhibited the opposite result from the kindergarten teachers. There was no significant difference in the frequency of conventional literacy guidance depending on the childs Hangeul acquisition level, but for high level children, the elementary school teachers gave more guidance regarding emergent literacy. In addition, when a child belonged to the high level group, the parents of both 5 year olds and first graders and the elementary school teachers all showed positive attitudes toward IHEP, whereas if the child belonged to the middle or low group, they showed dissatisfaction with the policy.
Third, the chosen method utilized by each sample group regarding literacy guidance was different. In terms of emergent literacy guidance, and the frequency at which it happens, kindergarten teachers scored the highest and the parents of 5 year olds scored the lowest. For conventional literacy guidance and its frequency, the elementary school teachers and the parents of first graders scored the highest, followed by the parents of 5 year olds, with the kindergarten teachers scoring the lowest.
Fourth, there was a big distinction between the four sample groups in the way they perceived IHEP. With regard to awareness (of the policy), the elementary school teachers scored the highest, and the kindergarten teachers did the lowest. Understanding of the policy itself was shown to be the most present in the elementary school teacher group, compared to the rest. Understanding of the benefits of the policy was best done by the parents of the first graders, as opposed to the elementary school teachers, who showed low scores on this particular subcategory. Concerning the openness(toward the policy), the elementary school teachers demonstrated the highest levels of openness, compared to the parents of 5 year olds.
In sum, this study has discovered that first graders score higher than 5 year olds on the level of Hangeul acquisition, that many 5 year olds have already acquired Hangeul, and that there are large individual differences within the same age group. The study also emphasizes the importance of preventing children from studying way too ahead of their levels, and the need for intervention programs for students who are slow learners. This study has also shown that there is a difference in the way in which the four sample groupsโkindergarten teachers, parents of 5 year olds, elementary school teachers, and parents of first gradersโperceive and understand literacy guidance and IHEP, depending on the level of Hangeul Acquisition(highยทmiddleยทlow) of the children. Such a discordance was corroborated by the results of the analyses, which showed that each group gave children literacy guidance in unalike ways and had different views and attitudes toward IHEP. In conclusion, this study compared the objective status of the Hangeul acquisition level of children who are in the transitional period between kindergarten and elementary school, and provided educational implications for children's literacy development, the basis for establishing appropriate literacy guidance methods for kindergarten and elementary teachers, parents, and policymakers, and proposed a possible future direction for IHEP.๋ณธ ์ฐ๊ตฌ๋ 5์ธ ์ ์์ 1ํ๋
์๋์ ํ๊ธ ํด๋ ์์ค์ ์์๋ณด๊ณ , ์ ์น์๊ณผ ์ด๋ฑํ๊ต ๊ต์ฌ์ ๋ถ๋ชจ์ ๋ฌธํด์ง๋์ ๊ต์ก๋ถ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์ ๋น๊ตํ๊ณ ์ ํ์๋ค. ์ด๋ฅผ ํตํด ์ ยท์ด ์ ์ด๊ธฐ ์๋์ ํ๊ธ ํด๋ ์์ค์ด ์ ยท์ด๋ฑ ๊ต์ฌ ๋ฐ ๋ถ๋ชจ์ ๋ฌธํด์ง๋์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์๊ณผ ๊ด๋ จ์ด ์๋์ง ์ดํด๋ณด๊ณ , ๋ฌธํด์ง๋์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์ ๋ํด ๋ค ์ง๋จ ๊ฐ์ ์ฐจ์ด๋ฅผ ๋น๊ตํ์๋ค.
์ด๋ฅผ ์ํด, ์๋๊ถ์ ์ ์น์ 5์ธ๋ฐ ๋ด์๊ต์ฌ 156๋ช
, 5์ธ์ ๋ถ๋ชจ 177๋ช
, ์ด๋ฑํ๊ต 1ํ๋
๋ด์๊ต์ฌ 155๋ช
, 1ํ๋
๋ถ๋ชจ 184๋ช
, ์ด 672๋ช
์ ์๋ฃ๋ฅผ ์์งํ์๋ค. ๊ต์ฌ์ ๋ถ๋ชจ๋ ์จ๋ผ์ธ ์ค๋ฌธ์กฐ์ฌ์ ์ฐธ์ฌํ์ฌ ์๋์ ํ๊ธ ํด๋ ์์ค, ๋ฌธํด์ง๋(๋ฐํ์ ๋ฌธํด์ง๋, ๊ด์ต์ ๋ฌธํด์ง๋), ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์(์ ์ฑ
์ธ์ง๋, ์ ์ฑ
์ดํด๋, ์ ์ฑ
์ด์ ์ธ์, ์ ์ฑ
์์ฉ๋)์ ์ธก์ ํ๋ ์ง๋ฌธ์ ์๋ตํ์๋ค. ์ด ์ค ์๋์ ํ๊ธ ํด๋ ์์ค์ ๋ํ์ฌ ๊ต์ฌ๋ ํ๊ธ ์๋๋ค์ ํ๊ท ์์ค์ผ๋ก ๋ณด๊ณ ํ๊ณ , ๋ถ๋ชจ๋ ์์ ์ ์๋
๋ฅผ ๊ธฐ์ค์ผ๋ก ํ๊ฐํ์๋ค. ์์งํ ์๋ฃ๋ SPSS Statistics 26.0์ ์ด์ฉํ์ฌ ๊ธฐ์ ํต๊ณ๋ถ์, ๋
๋ฆฝํ๋ณธ t-๊ฒ์ , ์ผ์๋ถ์ฐ๋ถ์, Scheffรฉ ์ฌํ๊ฒ์ ์ผ๋ก ๋ถ์ํ์๋ค. ๋ณธ ์ฐ๊ตฌ์ ์ฃผ์ ๊ฒฐ๊ณผ๋ ๋ค์๊ณผ ๊ฐ๋ค.
์ฒซ์งธ, ๊ต์ฌ์ ๋ถ๋ชจ์ ํ๊ฐ์ ์ํ๋ฉด 5์ธ ์ ์๋ค๋ณด๋ค 1ํ๋
์๋์ ํ๊ธ ํด๋ ์์ค์ด ์ ์ํ๊ฒ ๋์๋ค. ๊ทธ๋ฌ๋ 5์ธ ์ ์์ ํ๊ธ ํด๋ ์์ค๋ ์๋นํ ๋์ ๊ฒฝํฅ์ ๋ณด์ธ ๋ฐ๋ฉด, 1ํ๋
์๋ ์ค์๋ ๋ฎ์ ๊ฒฝ์ฐ๊ฐ ์๋ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค.
๋์งธ, ์๋์ ํ๊ธ ํด๋ ์์ค(์ยท์คยทํ)์ ๋ฐ๋ผ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ๋ฌธํด์ง๋์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์ ๊ฐ๊ฐ ์ฐจ์ด๊ฐ ์์๋ค. ๋จผ์ ์ ยท์ด๋ฑ ๋ถ๋ชจ๋ค์ ์๋
๊ฐ ํ๊ธ ํด๋ ์์ค ์์ง๋จ์ผ ๋ ๋ฐํ์ ยท๊ด์ต์ ๋ฌธํด์ง๋๋ฅผ ๋์์ ๋ ๋ง์ด ํ๋ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค. ๋ฐ๋ฉด ์ ์น์ ๊ต์ฌ๋ ํ๊ธ ํด๋ ์์ค์ ๋ฐ๋ผ ๋ฐํ์ ๋ฌธํด์ง๋์๋ ์ฐจ์ด๊ฐ ์์์ง๋ง, ํ๊ธ ํด๋ ์์ค ์์ง๋จ์ ๋ํด ๊ด์ต์ ๋ฌธํด์ง๋๋ฅผ ์ ์ํ๊ฒ ๋ ๋ง์ด ํ๋ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค. ์ด์ ๋ฐ๋๋ก 1ํ๋
๊ต์ฌ๋ ์๋์ ํ๊ธ ํด๋ ์์ค์ ๋ฐ๋ผ ๊ด์ต์ ๋ฌธํด์ง๋์๋ ์ฐจ์ด๊ฐ ์์์ง๋ง, ์์ง๋จ์ ๋ํด ๋ฐํ์ ๋ฌธํด์ง๋๋ฅผ ๋ ๋ง์ด ํ๋ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค. ๋ค์์ผ๋ก ์๋์ ํ๊ธ ํด๋ ์์ค์ด ์์ง๋จ์ผ ๋ 5์ธ์ ๋ถ๋ชจ, 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์ ๊ธ์ ์ ์ธ ๋ฐ๋ฉด, ์ค์ง๋จ ๋๋ ํ์ง๋จ์ธ ๊ฒฝ์ฐ ์ด ์ ์ฑ
์ ๋ง์กฑํ์ง ๋ชปํ๋ ๊ฒฝํฅ์ ๋ณด์๋ค.
์
์งธ, 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ๋ฌธํด์ง๋๋ ๋ค๋ฅธ ๋ฐฉ์์ผ๋ก ์ด๋ฃจ์ด์ง๋ค. ์ฐ์ ๋ฐํ์ ๋ฌธํด์ง๋๋ 5์ธ๋ฐ ๊ต์ฌ๊ฐ ๊ฐ์ฅ ๋ง์ด ํ๊ณ , 5์ธ์ ๋ถ๋ชจ๊ฐ ๊ฐ์ฅ ์ ๊ฒ ํ๋ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค. ๊ด์ต์ ๋ฌธํด์ง๋๋ 1ํ๋
๊ต์ฌ์ 1ํ๋
๋ถ๋ชจ๊ฐ ๊ฐ์ฅ ๋ง์ด ํ๊ณ , ๊ทธ๋ค์์ผ๋ก 5์ธ์ ๋ถ๋ชจ์ ์์ด๋ฉฐ, 5์ธ๋ฐ ๊ต์ฌ๋ ๋น๊ต์ ์ ๊ฒ ํ๋ ๊ฒ์ผ๋ก ํ์ธ๋์๋ค.
๋ท์งธ, ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ์ธ์์ ํฐ ์ฐจ์ด๊ฐ ๋ฐ๊ฒฌ๋์๋ค. ์ ์ฑ
์ธ์ง๋๋ 1ํ๋
๊ต์ฌ๊ฐ ๊ฐ์ฅ ๋์๊ณ , 5์ธ๋ฐ ๊ต์ฌ๊ฐ ๊ฐ์ฅ ๋ฎ์๋ค. ์ ์ฑ
์ดํด๋๋ 1ํ๋
๊ต์ฌ๋ค์ด ๋ค๋ฅธ ์ธ ์ง๋จ์ ๋นํด ์ ์ํ๊ฒ ๋์ ์์ค์ด์๋ค. ์ ์ฑ
์ด์ ์ธ์์ 1ํ๋
๋ถ๋ชจ ์ง๋จ์ด ๊ฐ์ฅ ๋์ ์์ค์, 1ํ๋
๊ต์ฌ ์ง๋จ์ด ๊ฐ์ฅ ๋ฎ์ ์์ค์ ๋ณด์๋ค. ์ ์ฑ
์์ฉ๋๋ 1ํ๋
๊ต์ฌ์ง๋จ์ด 5์ธ์ ๋ถ๋ชจ ์ง๋จ์ ๋นํด ์ ์ํ๊ฒ ๋์ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค.
๋ณธ ์ฐ๊ตฌ์ ๊ฒฐ๊ณผ๋ ํ๊ธ ํด๋ ์์ค์์ 5์ธ ์ ์๋ณด๋ค ์ด๋ฑ 1ํ๋
์๋ค์ด ๋ ๋์ ์์ค์ธ ๋์์, 5์ธ์๋ค์ ์๋น์๊ฐ ์ด๋ฏธ ํ๊ธ์ ํด๋ํ๊ณ , ๋์ผ์ฐ๋ น์ง๋จ ๋ด์์ ๊ฐ์ธ์ฐจ๊ฐ ํผ์ ์ฆ๋ช
ํ์ฌ, ๋๋ฆฌ๊ณผ์ ์ ๋ง๊ฒ ์ทจํ ์ ์ ๋ฌด๋ฆฌํ ํ๊ธ ์ ํ๊ต์ก์ ๋ฐฉ์งํ๋ ๋์์, ๋๋ฆฐ ํ์ต์๋ค์ ์ํ ๋น ๋ฅธ ๊ฐ์
์ด ์๊ตฌ๋จ์ ์ญ์คํ์๋ค. ๋ํ ์๋์ ํ๊ธ ํด๋ ์์ค(์ยท์คยทํ)์ ๋ฐ๋ผ ๋ถ๋ชจ์ ๊ต์ฌ ๋ค ์ง๋จ์ ๋ฌธํด์ง๋์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์๋ ์ฐจ์ด๊ฐ ์์์ด ๋ํ๋ฌ๋ค. ์ด์ ํจ๊ป ๋ค ์ง๋จ์ ๋ฌธํด์ง๋๊ฐ ๊ฐ๊ธฐ ๋ค๋ฅธ ๋ฐฉ์์ผ๋ก ์ด๋ฃจ์ด์ง๊ณผ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์ ํ์์์ธ๋ณ๋ก ์ฐจ๋ณ์ฑ์ ํ์ธํ์ฌ, ๋ค ์ง๋จ ๊ฐ์ ๋์์ด๋ชฝ์ ๋ถ๋ช
ํ๊ฒ ๋ณด์ฌ์ค๋ค. ๊ฒฐ๋ก ์ ์ผ๋ก ๋ณธ ์ฐ๊ตฌ๋ ์ทจํ ์ ํ ์๋์ ํ๊ธ ํด๋ ์์ค์ ๋ํ ๊ฐ๊ด์ ์ธ ์คํ๋ฅผ ๋น๊ตํ์ฌ ํจ๊ป ํ์
ํ๋ฉฐ ์๋์ ๋ฌธํด๋ฐ๋ฌ์ ๋๋ฌ์ผ ๊ต์ก์ ํจ์๋ฅผ ์ ๊ณตํ๊ณ , ์ ยท์ด๋ฑ ๊ต์ฌ-๋ถ๋ชจ-์ ์ฑ
์
์์๋ค์ด ์ ์ ํ ๋ฌธํด์ง๋ ๋ฐฉ์์ ์ ๋ฆฝํด์ผ ํ ๊ทผ๊ฑฐ๋ฅผ ์ ์ํ๋ฉฐ, ํ๊ธ์ฑ
์๊ต์ก์ ๊ฐ ๋์๊ฐ ์ฌ๋ฐ๋ฅธ ๋ฐฉํฅ์ ๋ํด ์ ์ํ์๋ค.โ
. ๋ฌธ์ ์ ๊ธฐ 1
โ
ก. ์ด๋ก ์ ๋ฐฐ๊ฒฝ ๋ฐ ์ ํ์ฐ๊ตฌ ๊ณ ์ฐฐ 5
1. ์๋์ ํ๊ธ ํด๋ 5
1) ํ๊ธ ํด๋์ ๊ฐ๋
5
2) ์๋์ ๋ฌธํด ๋ฐ๋ฌ๊ณผ ํ๊ธ ํด๋ 8
3) ์ ยท์ด๋ฑ ํ๊ธ ํด๋์ ํํฉ 10
2. ์๋ ๋ฌธํด์ง๋ 11
1) ๋ฌธํด์ง๋์ ๊ฐ๋
11
2) ๋ฌธํด์ง๋์ ์ ํ 14
3) ๋ถ๋ชจยท๊ต์ฌ ํํธ๋์ญ๊ณผ ๋ฌธํด์ง๋ 16
3. ํ๊ธ์ฑ
์๊ต์ก์ 19
1) ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ด์ฉ๊ณผ ์ํ 19
2) ์ ยท์ด์ฐ๊ณ์ ํ๊ธ์ฑ
์๊ต์ก์ 21
3) ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ๋ถ๋ชจ์ ๊ต์ฌ์ ์ธ์ 23
โ
ข. ์ฐ๊ตฌ๋ฌธ์ ์ ์ฉ์ด ์ ์ 26
1. ์ฐ๊ตฌ๋ฌธ์ 26
2. ์ฉ์ด์ ์ ์ 27
1) ์๋์ ํ๊ธ ํด๋ ์์ค 27
2) ๋ฌธํด์ง๋ 28
3) ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์ 28
โ
ฃ. ์ฐ๊ตฌ ๋ฐฉ๋ฒ ๋ฐ ์ ์ฐจ 29
1. ์ฐ๊ตฌ ๋์ 29
2. ์ฐ๊ตฌ ๋๊ตฌ 32
1) ์๋์ ํ๊ธ ํด๋ ์์ค 32
2) ๋ฌธํด์ง๋ 32
3) ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์ 33
3. ์ฐ๊ตฌ ์ ์ฐจ 34
1) ์๋น์กฐ์ฌ 34
2) ๋ณธ์กฐ์ฌ 35
4. ์๋ฃ ๋ถ์ 36
โ
ค. ์ฐ๊ตฌ ๊ฒฐ๊ณผ ๋ฐ ํด์ 37
1. 5์ธ ์ ์์ 1ํ๋
์๋์ ํ๊ธ ํด๋ ์์ค ๋น๊ต 37
1) ๊ต์ฌ๊ฐ ํ๊ฐํ 5์ธ ์ ์์ 1ํ๋
์๋์ ํ๊ธ ํด๋ ์์ค ๋น๊ต 37
2) ๋ถ๋ชจ๊ฐ ํ๊ฐํ 5์ธ ์ ์์ 1ํ๋
์๋์ ํ๊ธ ํด๋ ์์ค ๋น๊ต 40
3) ์๋์ ํ๊ธ ํด๋ ์์ค(์ยท์คยทํ) ๊ตฌ๋ถ 43
2. ์ ์น์ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, ์ด๋ฑ 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ๋ฌธํด์ง๋ ๋น๊ต 45
1) ์ ยท์ด๋ฑ ๊ต์ฌ์ ๋ถ๋ชจ์ ๋ฌธํด์ง๋์์ ์๋์ ํ๊ธ ํด๋ ์์ค(์ยท์คยทํ)์ ๋ฐ๋ฅธ ์ฐจ์ด ๋น๊ต 45
2) ์ ์น์ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, ์ด๋ฑ 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ ๊ฐ์ ๋ฌธํด์ง๋ ๋น๊ต 49
3. ์ ์น์ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, ์ด๋ฑ 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์ ๋น๊ต 52
1) ์ ยท์ด๋ฑ ๊ต์ฌ์ ๋ถ๋ชจ์ ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ธ์์์ ์๋์ ํ๊ธ ํด๋ ์์ค(์ยท์คยทํ)์ ๋ฐ๋ฅธ ์ฐจ์ด ๋น๊ต 52
2) ํ๊ธ์ฑ
์๊ต์ก์ ์ ๋ํ ์ ์น์ 5์ธ๋ฐ ๊ต์ฌ, 5์ธ์ ๋ถ๋ชจ, ์ด๋ฑ 1ํ๋
๊ต์ฌ, 1ํ๋
๋ถ๋ชจ ๊ฐ์ ์ธ์ ๋น๊ต 57
โ
ฅ. ๊ฒฐ๋ก ๋ฐ ๋
ผ์ 62
์ฐธ๊ณ ๋ฌธํ 71
๋ถ๋ก 87
Abstract 94์
Calcium chloride enhances the delivery of exosomes
Exosomes might have an unimproved potential to serve as effective delivery vehicles. However, when exosomes are developed for therapeutic applications, a method to enhance their delivery is important. This study aimed to evaluate wheather calcium chloride (CaCl2) or other chloride compounds could enhance exosome delivery to various cells without causing toxicity. Exosomes were purified from human serum by using the ExoQuick exosome precipitation kit. Isolated exosomes were mixed with CaCl2 at concentrations ranging from 100 ฮผM to 1 mM, and then washed using Amicon filter for treating the cells. The delivery efficiency of exosomes and the viability of the cells [HEK 293 (human kidney cells) and H9C2 (rat cardiomyocytes)] were evaluated. Cellular uptake of exosomes was observed using a confocal microscope based on PKH26 labeling of exosomes. CaCl2 increased the delivery of exosomes in a dose- and treatment time-dependent manner. In HEK 293 cells, a CaCl2 concentration of 400 ฮผM and exposure time of 12 h increased the delivery of exosomes by >20 times compared with controls. In H9C2 cells, a CaCl2 concentration of 400 ฮผM and exposure time of >24 h increased the delivery of exosomes by >400 times compared with controls. The viability of both cell lines was maintained up to a CaCl2 concentration of 1 mM. However, cobalt chloride, cupric chloride, and magnesium chloride did not change the delivery of exosomes in both cell lines. These results suggest that the use of CaCl2 treatment might be a useful method for enhancing the delivery of exosomes.ope
ํญ๋ ํธ๋ก๋ฐ์ด๋ฌ์ค ๊ฐ์ผ ์ญํ์ ๊ดํ ๋ชจ๋ธ๋ง์ฐ๊ตฌ.
ํ์๋
ผ๋ฌธ (๋ฐ์ฌ)-- ์์ธ๋ํ๊ต ๋ํ์ : ์์ฐ๊ณผํ๋ํ ํ๋๊ณผ์ ๊ณ์ฐ๊ณผํ์ ๊ณต, 2018. 2. ์ ๋์ฐ.A focus of this thesis is to develop a mathematical modeling approach to analyze the clinical data of Human immunodeficiency virus(HIV) acute infection. From the several studies, a remarkable stability of the HIV latent reservoir is detected despite the long-term treatment and advances in antiโretroviral therapy, and it has been recognized as a major barrier to HIV cure. We analyze several nonlinear mathematical models including the one that contains latent reservoir effect which provides consecutive viral replication and derive reproductive number (R0) which is a key index on HIV dynamics. For a quantitative analysis, we estimated parameters best describe time-series viral load measurements, obtained from published clinical study. We implement an efficient estimation method for the relevant parameters and numerical algorithm to solve the HIV infection dynamics. By using a nonlinear least square method for parameter estimation, analysis on the sensitivity parameters are performed for each model. In addition, we can obtain the total contribution of the reservoir processes to the productively infected T lymphocyte cells is also examined.
We also propose a new model for HIV infection dynamics. There has been some researches that some influencing fractions on the dynamics of blood flow have been associated with the severity of HIV infection. In order to explain the rheological behavior of HIV infection in T lymphocyte populations we attempt to modify Latent cell model with fractional order differentiation of order ฮฑ โ (0, 1]. The hemorheological parameters and fractional-order derivative in HIV system embody essential features of influencing fractions on the dynamics of blood flow associated with the severity of HIV infection. We show that the modified model has non-negative, bounded solutions and stable equilibrium points. Optimal fractional order and kinetic parameters are estimated by using the nonlinear weighted least-square method, the Levenberg-Marquardt algorithm, and Adams-type predictor-corrector method is employed for the numerical solution. The numerical results confirm that a value of fractional order (ฮฑ) representing the rheological behavior in plasma is significantly related with a density of lymphocyte population.Chapter 1 Introduction 1
1.1 Infection mechanism of HIV and Antiretroviral treatment 2
1.2 Latent reservoir and drug-resistant mutant in HIV infection 6
1.3 Modeling HIV infection dynamics in lymphocyte 9
1.4 Thesis overview 12
Chapter 2 Mathematical models for HIV infection dynamics 14
2.1 Models and their analysis 14
2.1.1 Three-component model 16
2.1.2 Chronical infection model 39
2.1.3 Latent infection model 46
2.2 Parameter estimation 52
2.2.1 Description of measurement data and their clinical result 53
2.2.2 An algorithm for parameter estimation 56
2.2.3 Initial guess for initial state density and model parameters 60
2.2.4 Analysis of parameter sensitivity 61
2.3 Numerical result 64
2.3.1 Sensitivity equations 64
2.3.2 Numerical simulation 66
2.4 Conclusion 70
Chapter 3 A fractional-order model for HIV infection 77
3.1 The fractional calculus 78
3.2 Motivation 80
3.3 Model derivation 83
3.4 Numerical methods 93
3.4.1 The fractional Adams method 94
3.4.2 Sensitivity equations 99
3.4.3 Initial guess for paramters and the fractional order 102
3.5 Numerical results: model fits and sample predictions 102
3.6 Conclusion 107Docto
Human peripheral bloodโderived exosomes for microRNA delivery
Exosomes serve important functions in cellโtoโcell communication and biological functions by serving as a delivery cargo shuttle for various molecules. The application of an improved delivery method for microRNAs (miRNAs/miRs) may enhance their potential as a therapeutic tool in cardiac diseases. Thus, the present study investigated whether human peripheral bloodโderived exosomes may be used as a delivery cargo system for miRNAs, and whether the delivery of miRโ21 using a human peripheral blood derivedโexosome may influence the degree of remodeling following myocardial infarction (MI). In H9C2 and HLโ1 cells, miRโ21 expression was successfully regulated by treatment with human peripheral blood derivedโexosomes loaded with an miRโ21 mimic or inhibitor compared with untreated cells. In addition, the mRNA and protein expression levels of SMAD family member 7 (Smad7), phosphatase and tensin homolog (PTEN) and matrix metalloproteinase 2 (MMP2), which are involved in cardiac fibrosis, were associated with the uptake of miRโ21 mimicโ or inhibitorโloaded exosomes. Similarly, the in vivo mRNA and protein expression of Smad7, PTEN and MMP2 were altered following treatment with miRโ21 mimicโ or inhibitorโloaded exosomes. Furthermore, miRโ21 mimicโloaded exosomes enhanced fibrosis, whereas miRโ21 inhibitorโloaded exosomes reduced fibrosis in a mouse MI model. These results suggested that miRNAโloaded human peripheral blood derivedโexosomes may be used as a therapeutic tool for cardiac diseases.ope
Long-term Clinical Outcomes and Prognostic Factors After Endovascular Treatment in Patients With Chronic Limb Threatening Ischemia
Background and objectives: Endovascular therapy (EVT) first strategy has been widely adopted for the treatment of chronic limb threatening ischemia (CLTI) patients in real-world practice. This study aimed to investigate long-term outcomes of CLTI patients who underwent EVT and identify prognostic factors.
Methods: From the retrospective cohorts of a Korean multicenter endovascular therapy registry, 1,036 patients with CLTI (792 men, 68.8 ยฑ 9.5 years) were included. The primary endpoint was amputation-free survival (AFS) defined as the absence of major amputation or death. Secondary endpoints were major adverse limb events (MALE; a composite of major amputation, minor amputation, and reintervention).
Results: Five-year AFS and freedom from MALE were 69.8% and 61%, respectively. After multivariate analysis, age (hazard ratio [HR], 1.476; p<0.001), end-stage renal disease (ESRD; HR, 2.340; p<0.001), Rutherford category (RC) 6 (HR, 1.456; p=0.036), and suboptimal EVT (HR, 1.798; p=0.005) were identified as predictors of major amputation or death, whereas smoking (HR, 0.594; p=0.007) was protective. Low body mass index (HR, 1.505; p=0.046), ESRD (HR, 1.648; p=0.001), femoropopliteal lesion (HR, 1.877; p=0.004), RC-6 (HR, 1.471; p=0.008), and suboptimal EVT (HR, 1.847; p=0.001) were predictors of MALE. The highest hazard rates were observed during the first 6 months for both major amputation or death and MALE. After that, the hazard rate decreased and rose again after 3-4 years.
Conclusions: In CLTI patients, long-term outcomes of EVT were acceptable. ESRD, RC-6, and suboptimal EVT were common predictors for poor clinical outcomes.
Trial registration: ClinicalTrials.gov Identifier: NCT02748226.ope
Associates and Prognosis of Giant Left Atrium; Single Center Experience
Background: Left atrial (LA) remodeling develops as a result of longstanding pressure overload. However, determinants and clinical outcome of excessive remodeling, so called giant left atrium (GLA), are not clear.
Methods: Clinical characteristics of patients with GLA (antero-posterior diameter higher than 65 mm), including echo-Doppler parameters, and follow-up clinical outcomes from a tertiary referral hospital were investigated.
Results: Among 68519 consecutive primary patients who underwent echocardiography over a period of 10 years, data from 163 GLA cases (0.24%) were analyzed. Main causes were significant rheumatic mitral stenosis (n = 58, 36%); other causes comprised significant rheumatic mitral regurgitation (MR; n = 10, 6%), mitral valve (MV) prolapse or congenital mitral valvular disease (MVD) (n = 20, 12%), and functional MR (n = 25, 15%). However, mild rheumatic MV disease (n = 4, 3%) or left ventricular (LV) systolic or diastolic dysfunction without significant MR (n = 46, 28%) were also causes of GLA. During median follow-up of 22 months, 42 cases (26%) underwent composite events. MV surgery was related to lower rate of composite events. In multivariate analysis, MV surgery, elevated pulmonary arterial systolic pressure, and increased LA volume index were independent predictors of future events (p < 0.05) regardless of underlying diseases or history of MV surgery.
Conclusion: Although rheumatic MVD with atrial fibrillation is the main contributor to GLA, longstanding atrial fibrillation with LV dysfunction but without MVD also could be related to GLA. Even in GLA state, accurate measurement of LA volume is crucial for risk stratification for future events, regardless of underlying disease.ope
Coronary Artery Aneurysm after Second-Generation Drug-Eluting Stent Implantation
PURPOSE: We evaluated the incidence, predictors, and prognosis of coronary artery aneurysm (CAA) after second-generation drug-eluting stent (DES) implantation.
MATERIALS AND METHODS: A total of 976 consecutive patients (1245 lesions) who underwent follow-up angiography after second-generation DES implantation were analyzed. Incidence and predictors of CAA were assessed, and clinical prognosis was compared with 34 cases of CAA after first-generation DES implantation using previous CAA registry data.
RESULTS: All 10 cases of CAA (0.80% per lesion) in 10 patients (1.02% per patient) were detected at follow up. Compared to lesions without CAA, those with CAA had greater involvement of the proximal segment (90% vs. 51%, p=0.014), a higher proportion of pre-intervention, a Thrombolysis in Myocardial Infarction score of 0 or 1 flow (80% vs. 16%, p<0.001), more chronic total occlusions (40% vs. 10%, p<0.001), and longer implanted stents (41.9ยฑ23.2 mm vs. 28.8ยฑ14.8 mm, p=0.006). As for CAA morphology, instances of CAA after second-generation DES were predominantly the single fusiform type (90%), whereas instances of CAA after first-generation DES were multiple saccular (47%) and single saccular (35%) types (p<0.001). Myocardial infarction with stent thrombosis occurred in 5 patients with CAA after first-generation DES (15%), and no adverse events were observed in patients with CAA after second-generation DES over a median follow-up duration of 4.3 years (p=0.047, log-rank).
CONCLUSION: Although CAAs after second-generation DES implantation were detected at a similar incidence to that for CAAs after first-generation DES implantation, second-generation DES-related CAAs had different morphologies and more benign clinical outcomes versus first-generation DES-related CAAs.ope
Clinical evidence of initiating a very low dose of sacubitril/valsartan: a prospective observational analysis
Sacubitril/valsartan is superior to enalapril in reducing the risks of cardiovascular death and preventing hospitalization in patients with heart failure and reduced ejection fraction (HFrEF). However, patients often do not receive sacubitril/valsartan because of concerns about hypotension. We examined the feasibility of initiating sacubitril/valsartan at a very low dose (VLD) in potentially intolerant patients with HFrEF and subsequent dose up-titration, treatment persistence and outcomes. We analyzed 206 patients with HFrEF grouped according to starting sacubitril/valsartan dose. The VLD group (n = 106) commenced 25 mg twice daily, and the standard-dose (SD) group (n = 100) started on โฅ 50 mg twice daily. Baseline systolic blood pressure was 103 ยฑ 12 mmHg vs. 119 ยฑ 14 mmHg in the SD group (P < 0.001). The maximal target dose achievement rate was higher in the SD group (27.0% vs 9.4%, p = 0.001) and the VLD group experienced more dose up-titrations and fewer down-titrations than the SD group. The VLD group had a decrease in N-terminal prohormone of brain natriuretic peptide (NT-proBNP) similar to the SD group and a similar increase in left ventricular ejection fraction. There were no significant differences in symptomatic hypotension, worsening renal function, hyperkalemia, cardiovascular mortality, and rehospitalization due to HF between the two groups during follow-up period. In patients considered by the treating physician likely to be intolerant of sacubitril/valsartan, initiation with 25 mg twice daily was generally possible and patients remained in therapy, with similar decreases in NT-proBNP and increases in left ventricular ejection fraction to those observed in patients receiving SD sacubitril/valsartan.ope
์น์ฃผ์งํ์์ Toll-like receptor ์ญํ ์ ๋ํ ๊ณ ์ฐฐ
ํ์๋
ผ๋ฌธ (์์ฌ)-- ์์ธ๋ํ๊ต ๋ํ์ : ์น์ํ๊ณผ, 2012. 2. ์ด์ฑ์ค.Inflammation is an excessive immune response that destroys host tissues and periodontitis is caused by inflammation. The development of the disease can be classified into the initial, early, established and advanced lesions.
Toll-like receptors(TLRs) are pattern-recognition receptors that recognize specific pathogen-associated molecular patterns and initiate appropriate immune responses against them. TLRs facilitate expression of pro-inflammatory mediators such as cytokines by MyD88-dependent pathway and MyD88-independent pathway. TLRs are mainly expressed on the immune cells such as macrophage, neutrophil and monocyte, but it turns out that the cells in periodontal tissue also express TLRs and the interaction between TLR and their specific ligand has an important role in progression of periodontal disease. It seems that TLRs on epithelial cells make a protective barrier and become tolerized during sustained exposure to bacterial structures such as LPS. But once pathogens or opportunists invade and destroy the epithelial barriers, it is possible that TLRs on the cells in underlying connective tissues directly contact with bacterial products. It causes hyper-inflammatory responses because these TLRs are not tolerized unlike TLRs on gingival epithelial cells.
There are lots of attempts to target TLRs as treatment of inflammatory diseases. It could be helpful to study the role of TLRs in periodontal disease to make use of TLRs in therapies of periodontal disease.์ผ์ฆ๋ฐ์์ host์ ๋ฉด์ญ๋ฐ์์ ํ๋๋ก์จ ์ด๊ฒ์ด ๊ณผ๋ํ์ฌ ๋ฐ์์ด ์ผ์ด๋๋ ์ฃผ๋ณ์ host tissue๋ฅผ ํ๊ดดํ๋ ํ์์ด๋ฉฐ ์น์ฃผ์ผ์ ์ด๋ฌํ ์ผ์ฆ๋ฐ์์ ์ํ ์งํ์ด๋ผ๊ณ ํ๊ฒ ๋ค. ์น์ฃผ์งํ์ ์งํ์ ์ด๊ธฐ, ์กฐ๊ธฐ, ํ๋ฆฝ๊ธฐ, ์งํ๊ธฐ๋ก ๋๋์ด์ง ์ ์๋ค. Toll-like receptor๋ ๋ฏธ์๋ฌผ์ pathogen-associated molecular patterns์ด๋ผ๊ณ ํ๋ ๊ตฌ์กฐ๋ฅผ ์ธ์ํ๋ฏ๋ก์จ ๋ฉด์ญ๋ฐ์์ ๊ฐ์์์ ์ค์ํ ์ญํ ์ ํ๋ค๊ณ ์๋ ค์ ธ ์๋ค. Toll-like receptor๋ MyD88-dependent pathway, MyD88-independent pathway๋ฅผ ํตํด์ pro-inflammatory mediators์ ๋ฐํ์ ์ด์งํ๋ ๊ฒ์ผ๋ก ์๋ ค์ ธ ์๋ค. ์ด๋ฌํ Toll-like receptor๋ macrophage, neutrophil, monocyte์ ๊ฐ์ immune cell์ ์ฃผ๋ก ๋ฐํ๋์ง๋ง ์น์ฃผ์กฐ์ง์์ epithelial cell, gingival fibroblast, periodontal fibroblast, cementoblast, osteoblast, osteoclast ๋ฑ์์๋ Toll-like receptor๊ฐ ๋ฐํ๋จ์ด ํ์ธ๋์์ผ๋ฉฐ ์ด๋ฌํ ์ธํฌ๋ค์ ์กด์ฌํ๋ Toll-like receptor์ ligand์ ์ํธ์์ฉ์ด ์น์ฃผ์งํ์ ์งํ์ ์ค์ํ ์ญํ ์ ํ๋ค. steady state์์๋ ์น์์ ์ํผ์์ ๋ฐํ๋๋ Toll-like receptor๊ฐ ์์ฉํ์ฌ barrier๋ฅผ ๋จผ์ ํ์ฑํ๊ณ ๊ทธ ์ดํ์ ์ง์์ ์ธ ์๊ทน์ ๋ํด์๋ tolerance๋ฅผ ๋ํ๋ด์ด ๋ ์ด์์ inflammation์ด ์งํ๋์ง ์๊ฒ ์ ํํ์ฌ protection ์์ฉ์ ํ์ง๋ง virulence factor๋ฅผ ๊ฐ์ง๋ pathogen์ด๋ ๊ธฐํ๊ฐ์ผ๊ท ๋ฑ์ด ์ด๋ฌํ ์ํผ์ฅ๋ฒฝ์ ํ๊ดด์์ผ ์น์ฃผ์กฐ์ง์ ๋ ๊น์ ์ธต์ผ๋ก ์นจํฌํ๊ฒ ๋๋ฉด tolerance๋ฅผ ๋ํ๋ด์ง ์์ Toll-like receptor์ ์ง์ ์ ์ผ๋ก ์ ์ดํ๊ฒ ๋์ด pro-inflammatory cytokine์ ๋ถ๋น๊ฐ ์ฆ๊ฐ๋์ด ์น์ฃผ์งํ์ด ์งํ๋๋ ๊ฒ์ผ๋ก ์๊ฐ๋๋ค.
๋ฉด์ญ๋ฐ์์์ Toll-like receptor์ ์ญํ ์ด ๋ฐํ์ง๊ธฐ ์์ํ๋ฉด์ Toll-like receptor๋ฅผ target์ผ๋ก ํ ์ผ์ฆ์ฑ ์งํ์ ๋ํ ์น๋ฃ์ ๊ดํ ์ฐ๊ตฌ๊ฐ ํ๋ฐํ ์ด๋ฃจ์ด์ง๊ณ ์์ผ๋ฉฐ ์ด์ ๋ฐ๋ผ ์น์ฃผ์งํ์์๋ Toll-like receptor signaling pathway๋ฅผ ์ด์ฉํ ์น๋ฃ๋ฒ์ ๋ํ ๊ฐ๋ฅ์ฑ์ด ์ ์๋๊ณ ์๋คMaste
Color Experience and Reductive Explanation โA Defense of Dispositional Higher-order Theoryโ
์์์ ๊ฒฝํ์ ๊ดํ ์ฑํฅ์ ๊ณ ์ฐจ ์ด๋ก ์ ๊ฒฝ์ ์ด๋ก ์ธ ์ผ์ฐจ์ด๋ก ๊ณผ ๊ณ ์ฐจ์ ์ฌ๊ณ ์ด๋ก ์ ๋์ ์ ๊ทน๋ณตํ๋ ค๋ ์๋์์ ์ ์๋์๋ค. ์ฑํฅ์ ๊ณ ์ฐจ์ด๋ก ์ ๋จ์ํ ์ผ์ฐจ ์ด๋ก ์ ๋์ ๋ฟ๋ง ์๋๋ผ ์ผ์ฐจ ์ด๋ก ๊ณผ ๊ณ ์ฐจ ์ด๋ก ์ด ์ ์ ์ฌ๋ฌ ํํ์ ๋ฌด์์์ ์ง๊ฐ ์ํ์ ๋ํ ์ค๋ช
์ด ์ด๋ ต๋ค๋ ์ ๋ํ ๊ทน๋ณตํ ์ ์๋ค. ๋ฐ๋ฉด, ์ผ์ฐจ ์ด๋ก ์ ์ค๋ช
์ด ๋ณด์ด๋ ๊ฐ์ ์ด์๋ ์ง๊ฐ ๊ฒฝํ์ ๋ณธ๋์ฑ์ ๋ํ ์ค๋ช
์ ๋ํ์ฌ๋ ์ฑํฅ์ ๊ณ ์ฐจ ์ด๋ก ์ด ์ทจ์ฝํ ๊ฒ์ฒ๋ผ ๋ณด์ด๊ธฐ๋ ํ๋ค. ํ์ง๋ง, ํ์๋ ์ฐ๋ฆฌ ์ง๊ฐ ๊ฒฝํ์ด ๋ณธ๋์ ์ด๋ผ๋ ๋น์ฐ์ ์ฌ๊ฒจ์ก๋ ๊ฐ์ ์์ฒด๊ฐ ์คํ๋ ค ์ฐ๋ฆฌ์ ์ง๊ฐ ๊ฒฝํ์ ์์ด์ ์์๋ก ์งง๊ฒ ์์ ๋ ๊ด์ฐฐ์๊ฐ์ ๊ธฐ์ธํ๋ค๊ณ ๋ฐฉ์ดํ์๋ค. ์ด๋ฐ ์ ์์ ์ฑํฅ์ ๊ณ ์ฐจ ์ด๋ก ์ ์ง๊ฐ ๊ฒฝํ์ ๋ํด ์๋ฌด๋ฐ ๋ฐ์ฑ ์์ด ๊ฐ์ ํ๋ ์ ์ ๋ค์ ๋นํ์ ์ผ๋ก ์ฑ์ฐฐํ๊ฒ๋ํ๋ ๊ธฐํ๋ฅผ ์ ๊ณตํ๋ค. ๋ํ, ์ฑํฅ์ ๊ณ ์ฐจ ์ด๋ก ์ ์๊น์ ๋ฌผ๋ฆฌ์ ์์ฑ์ด ๋ณธ๋ ์ฑํฅ์ ์์ฑ์ ๊ฐ์ง๊ณ ์์์ ์ ์ ์ผ๋ก ๋ถ์ ํ์ง ์์ผ๋ฉด์ ์๊น์ด ์ง๊ฐ๋๋ ์ธ๊ณผ ๊ณผ์ ๋ํ ๊ณผํ์ ์ฑ๊ณผ์๋ ์ผ๊ด์ ์์ ๋ฐํ๋ฉด์ ๋ค์ํ ์ง๊ฐ ๊ฒฝํ๋ค์ ์ฐจ์ด๋ฅผ ๋ฐํ์ค๋ค๋ ์ ์์ ๋ณด๋ค ์ธ๋ จ๋ ์ค๋ช
์ด๋ผ๊ณ ํ ์ ์๋ค.
This paper argues for a form of representational theory of color and Peter Carruthers dispositionalist version of the higher-order thought theory. The dispositionalist account is a higher-order thought theory, yet overcomes the shortcomings of both the first-order theory and the higher-order thought theory. The theory I embrace explains conscious states such as color perception as available to a
higher-order of thought. The difficulty with the account lies in its non-categorical and its non-actual characteristics that become its strength in explicating the different forms of non-phenomenally conscious perceptual states. On the downside, the account seems to have difficulty in explaining the non-dispositional nature of our perceptual experience. Rosenthal criticizes that the theory has difficulty explaining our phenomenal aspects of mental states because disposition alone has no causal role in making the information actual. I argue against this criticism by raising the question of the received assumption that our perceptual experience
is intrinsic. The impression that our color experience is intrinsic might be misleading due to the short time slot in observation.
Unlike the traditional characteristic of color, our color experience can be dispositional depending on the duration of observation. In conclusion, Carruthers dispositional account of higher-order thought
theory is a more refined account that it is consistent with scientific facts of color and that it specifies different kinds of nonconscious color perception.์ด ๋
ผ๋ฌธ์ 2007๋
๋ ์ ๋ถ์ฌ์(๊ต์ก๊ณผํ๊ธฐ์ ๋ถ ์ธ๋ฌธ์ฌํ ์ฐ๊ตฌ์ญ๋๊ฐํ์ฌ์
)์ผ๋ก ํ๊ตญ์ฐ๊ตฌ์ฌ๋จ์ ์ง์์ ๋ฐ์ ์ฐ๊ตฌ๋์์. [KRF-354-2007-1-A00052