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    ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์— ์˜ํ•œ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์˜ ์„ฑ์žฅ๊ณผ ๋ฐ”์ด์˜คํ•„๋ฆ„ ์ €ํ•ด ํšจ๊ณผ

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    ํ•™์œ„๋…ผ๋ฌธ(์„์‚ฌ) -- ์„œ์šธ๋Œ€ํ•™๊ต๋Œ€ํ•™์› : ์น˜์˜ํ•™๋Œ€ํ•™์› ์น˜์˜ํ•™๊ณผ, 2021.8. ๋ฐ•ํƒœํ™˜.1. ๋ชฉ์  ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์€ ๊ทธ๋žŒ์–‘์„ฑ์„ธ๊ท ์œผ๋กœ ๋†’์€ ๋ถ€์ฐฉ๋Šฅ๋ ฅ๊ณผ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ ๋Šฅ๋ ฅ์œผ๋กœ ๊ตฌ๊ฐ• ๋‚ด ์งˆํ™˜์ธ ์ถฉ์น˜, ์น˜์ฃผ ์งˆํ™˜ ๋ณ‘์†Œ์—์„œ ์ฃผ๋กœ ๋ฐœ๊ฒฌ๋˜๋Š” ๋ฐ•ํ…Œ๋ฆฌ์•„์ด๋‹ค. ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ๋Š” ํ˜ธ๊ธฐ, ํ˜๊ธฐ ํ™˜๊ฒฝ ๋ชจ๋‘์—์„œ ์ƒ์กดํ•˜๋ฉฐ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์ด ๊ฐ€๋Šฅํ•˜๋‹ค. ๊ทธ๋Ÿฌ๋‚˜, ํ˜„์žฌ์˜ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์„ ๋น„๋กฏํ•œ ๊ตฌ๊ฐ• ๋‚ด ๋ฏธ์ƒ๋ฌผ์˜ ์ œ์–ด ๋ฐฉ๋ฒ•์€ ์น˜์•„์˜ ๊ฐ•๋„ ๊ฐ์†Œ, ๋ฏธ๊ฐ์˜ ๋ณ€ํ™” ๋“ฑ์˜ ๋ถ€์ž‘์šฉ์„ ๋‚ด์žฌํ•˜๊ณ  ์žˆ์–ด ์ฐจ์„ธ๋Œ€ ๋ฏธ์ƒ๋ฌผ ์ œ์–ด ๋ฐฉ๋ฒ•์ด ํ•„์š”ํ•˜๋‹ค. ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์€ ๋ฏธ์ƒ๋ฌผ์˜ ๋ฐœํšจ์ž‘์šฉ์œผ๋กœ ์ƒ์„ฑ๋˜๋Š” ๋Œ€์‚ฌ์‚ฐ๋ฌผ๋กœ ์ตœ๊ทผ์˜ ์—ฐ๊ตฌ์—์„œ๋Š” ์žฅ๋‚ด ๋ณ‘์›๊ท ์˜ ์„ฑ์žฅ์„ ์–ต์ œํ•˜๊ณ  ๋ฉด์—ญ๋ฐ˜์‘ ์กฐ์ ˆ์„ ์กฐ์ ˆํ•  ์ˆ˜ ์žˆ๋‹ค๋Š” ๊ฒƒ์ด ๋ฐํ˜€์ ธ ์žˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜, ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ธ acetate, propionate, ํ˜น์€ butyrate๊ฐ€ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์— ๋Œ€ํ•œ ์˜ํ–ฅ์€ ์•Œ๋ ค์ ธ ์žˆ์ง€ ์•Š๋‹ค. ์ด์— ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋‹ค์–‘ํ•œ ํ™˜๊ฒฝ์—์„œ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์ด ์„ฑ์žฅํ•  ๋•Œ์™€ ์ƒ๋ฌผ๋ง‰ํ˜•์„ฑ์— ๋Œ€ํ•œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์˜ ์˜ํ–ฅ์„ ์•Œ์•„๋ณด์•˜๋‹ค. 2. ๋ฐฉ๋ฒ• ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ด ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท  ์ค‘ Streptococcus gordonii์˜ ์„ฑ์žฅ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์„ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด ์—ฌ๋Ÿฌ ๋†๋„์˜ acetate, propionate, ํ˜น์€ butyrate๋ฅผ ์ฒ˜๋ฆฌํ•œ ํ›„ ์ •์  ํ˜ธ๊ธฐ์„ฑ ํ™˜๊ฒฝ์—์„œ ์„ฑ์žฅ์‹œํ‚จ ํ›„ ๋ถ„๊ด‘๊ด‘๋„๊ณ„๋กœ ํก๊ด‘๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. S. gordonii๊ฐ€ ๋‹ค์–‘ํ•œ ํ™˜๊ฒฝ์—์„œ ์„ฑ์žฅํ•  ๋•Œ์˜ ์„ฑ์žฅ์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์„ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด ํ˜๊ธฐ์™€ ํ˜ธ๊ธฐ ๊ทธ๋ฆฌ๊ณ  ๋™์  ๋˜๋Š” ์ •์  ์ƒํƒœ์—์„œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์„ ์ฒ˜๋ฆฌ ํ•œ ํ›„ ํก๊ด‘๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ๋˜ํ•œ, S. gordonii ์ž„์ƒ ๋ถ„๋ฆฌ ๊ท ์— ๋Œ€ํ•œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์˜ ์˜ํ–ฅ์„ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์„ ์ฒ˜๋ฆฌ ํ›„ ๋‹ค์–‘ํ•œ ์„ฑ์žฅํ™˜๊ฒฝ์—์„œ ์„ฑ์žฅ์‹œํ‚จ ํ›„ ํก๊ด‘๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ๋‹ค๋ฅธ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ๋“ค์˜ ๋‹ค์–‘ํ•œ ์„ฑ์žฅํ™˜๊ฒฝ์—์„œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์— ๋Œ€ํ•ด ์–ด๋– ํ•œ ์˜ํ–ฅ์„ ๋ฐ›๋Š”์ง€ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด Streptococcus sanguinis, Streptococcus oralis, Streptococcus mitis, Streptococcus salivarius, Streptococcus sobrinus, ์™€ Streptococcus mutans๋ฅผ ํ˜๊ธฐ์™€ ํ˜ธ๊ธฐ ๊ทธ๋ฆฌ๊ณ  ๋™์  ๋˜๋Š” ์ •์  ์ƒํƒœ์—์„œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์„ ์ฒ˜๋ฆฌํ•œ ํ›„ ์„ฑ์žฅ์‹œํ‚จ ํ›„ ํก๊ด‘๋„๋ฅผ ์ธก์ •ํ•˜์˜€๋‹ค. ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ด ์ •๊ท ์  ํ˜น์€ ์‚ด๊ท ์  ์ž‘์šฉ์„ ํ•˜๋Š”์ง€ ๋ณด๊ธฐ ์œ„ํ•ด S. gordonii์—์„œ minimum inhibitory concentration (MIC)/minimum bacteriacidal concentration (MBC) ํ…Œ์ŠคํŠธ๋ฅผ ์ง„ํ–‰ํ•˜์˜€๋‹ค. ์ด์— ๋”ํ•ด ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์— ๋Œ€ํ•œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์˜ ์˜ํ–ฅ์„ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด ๊ฒฝ๊ตฌ ์—ฐ์‡„์ƒ๊ตฌ๊ท ์„ ์—ฌ๋Ÿฌ ๋†๋„์˜ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ๊ณผ ํ•จ๊ป˜ ์ƒ๋ฌผ๋ง‰ํ˜•์„ฑ์„ ์ง„ํ–‰ํ•˜์˜€๋‹ค. ๊ทธ ์ค‘ S. gordonii๋ฅผ ๋Œ€ํ‘œ๋กœ ํ•˜์—ฌ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ด S. gordonii์— ์ดˆ๊ธฐ ๋ถ€์ฐฉ, ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ ํ˜น์€ ํ˜•์„ฑ๋œ ์ƒ๋ฌผ๋ง‰์— ๋Œ€ํ•œ ์˜ํ–ฅ์„ ํ™•์ธํ•˜๊ธฐ ์œ„ํ•ด ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ด ์ฒ˜๋ฆฌ๋œ S. gordonii์— ์ƒ๋ฌผ๋ง‰์„ ๊ฐ ์‹œ๊ฐ„๋ณ„๋กœ ์ •๋Ÿ‰ ํ•˜์˜€๊ณ  ์ƒ๋ฌผ๋ง‰์„ ํ˜•์„ฑํ•œ ๋’ค ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์„ ์ฒ˜๋ฆฌํ•˜์—ฌ ์ƒ๋ฌผ๋ง‰์„ ์ •๋Ÿ‰ ํ•˜์˜€๋‹ค. ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ด S. gordonii์˜ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ ์ €ํ•ด ๊ธฐ์ „์„ ์•Œ๊ธฐ ์œ„ํ•ด, ์ฟผ๋Ÿผ์„ผ์‹ฑ ์ธ์ž์ธ AI-2 ์–ต์ œ์ œ๋ฅผ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ๊ณผ ๋™์‹œ ์ฒ˜๋ฆฌํ•˜์˜€๊ณ , ์ฟผ๋Ÿผ์„ผ์‹ฑ์— ๊ด€๋ จ๋œ ์œ ์ „์ž์— ๋Œ€ํ•œ ์‹ค์‹œ๊ฐ„ ์—ฐ์‡„์ค‘ํ•ฉ๋ฐ˜์‘์„ ์‹ค์‹œํ•˜์˜€๋‹ค. 3. ๊ฒฐ๊ณผ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ธ acetate, propionate, ํ˜น์€ butyrate๋Š” ๋ชจ๋‘ S. gordonii์˜ ์„ฑ์žฅ์„ ์–ต์ œํ•˜์˜€์ง€๋งŒ, propionate๊ฐ€ S. gordonii์˜ ์„ฑ์žฅ์„ ๊ฐ€์žฅ ํšจ๊ณผ์ ์œผ๋กœ ์–ต์ œํ•˜์˜€๋‹ค. ๋‹ค์–‘ํ•œ ์„ฑ์žฅ ํ™˜๊ฒฝ ์ค‘ ์ •์  ํ˜๊ธฐ ์ƒํƒœ์ผ๋•Œ์˜ ์–ต์ œํšจ๊ณผ๊ฐ€ ๊ฐ€์žฅ ์ปธ๋‹ค. ๋˜ํ•œ, propionate์˜ ํ˜๊ธฐํ™˜๊ฒฝ์—์„œ์˜ ์–ต์ œํšจ๊ณผ๋Š” S. gordonii์˜ ์ž„์ƒ ๋ถ„๋ฆฌ ๊ท  5์ข…์—์„œ๋„ ๋™์ผํ•œ ํšจ๊ณผ๋ฅผ ๋ณด์˜€๋‹ค. ๋‹ค๋ฅธ ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์— ๋Œ€ํ•œ propionate์˜ ์„ฑ์žฅ ์–ต์ œ ํšจ๊ณผ๋Š” ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์˜ ์„ฑ์žฅ ํ™˜๊ฒฝ์— ๋”ฐ๋ผ ๋‹ฌ๋ผ ์กŒ๋‹ค. S. gordonii, S. sanguinis, ์™€ S. oralis๋Š” ํ˜๊ธฐ ํ™˜๊ฒฝ์—์„œ ๊ฐ€์žฅ ํฌ๊ฒŒ ์„ฑ์žฅ์ด ์–ต์ œ๋˜์—ˆ๋‹ค. S. salivarius์˜ ๊ฒฝ์šฐ์—๋Š” ํ˜๊ธฐ์™€ ํ˜ธ๊ธฐ ์ •์  ๋˜๋Š” ๋™์  ์ƒํƒœ ๋ชจ๋‘ ๊ท ์ผํ•œ ์„ฑ์žฅ ๊ฐ์†Œ๋ฅผ ๋ณด์˜€์œผ๋ฉฐ S. mitis ๋Š” ๋™์  ์ƒํƒœ์ผ ๋•Œ ์„ฑ์žฅ์ด ์–ต์ œ๋˜์—ˆ๋‹ค. S. sobrinus์™€ S. mutans๋Š” ํ˜ธ๊ธฐ์„ฑ ํ™˜๊ฒฝ์—์„œ ์„ฑ์žฅ์ด ์–ต์ œ๋˜์—ˆ๋‹ค. ๋˜ํ•œ, MIC/MBC ํ…Œ์ŠคํŠธ ๊ฒฐ๊ณผ propionate๋Š” ์‚ด๊ท ์  ์ž‘์šฉ์„ ํ•˜์ง€ ์•Š๊ณ  ์ •๊ท ์  ์ž‘์šฉ์„ ํ†ตํ•ด ์„ฑ์žฅ์„ ์–ต์ œํ•จ์„ ๋‚˜ํƒ€๋ƒˆ๋‹ค. ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์˜ ์˜ํ•œ ๊ฒฝ๊ตฌ ์—ฐ์‡„์ƒ๊ตฌ๊ท ์˜ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์— ๋Œ€ํ•œ ์˜ํ–ฅ์€ ๋‹ค์–‘ํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. S. gordonii์˜ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์˜ ๊ฒฝ์šฐ์—๋Š” acetate, propionate, butyrate ๋ชจ๋‘์—๊ฒŒ์„œ ์–ต์ œ ๋˜์—ˆ์œผ๋‚˜ ์„ฑ์žฅ์— ์˜ํ–ฅ์„ ์ฃผ์ง€ ์•Š๊ณ  ์ƒ๋ฌผ๋ง‰์„ ์–ต์ œ ์‹œํ‚ค๋Š” ๊ฒƒ์€ acetate์˜€๋‹ค. Acetate, propionate, butyrate๋Š” S. gordonii์˜ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์„ ์ดˆ๊ธฐ๋‹จ๊ณ„์—์„œ๋ถ€ํ„ฐ ์–ต์ œํ•˜์˜€๊ณ , ์ด๋ฏธ ํ˜•์„ฑ๋œ ์ƒ๋ฌผ๋ง‰์—์„œ๋Š” ์•„๋ฌด๋Ÿฐ ํšจ๊ณผ๋ฅผ ๋ผ์น˜์ง€ ์•Š์•˜๋‹ค. ๋˜ ํ•œ, acetate์˜ S. gordonii ์ƒ๋ฌผ๋ง‰ ์–ต์ œ ๊ธฐ์ „์€ ์ฟผ๋Ÿผ์„ผ์‹ฑ ์ธ์ž์ธ CSP๋ฅผ ์–ต์ œํ•˜๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. 4. ๊ฒฐ๋ก  ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์ธ acetate, propionate, butyrate๊ฐ€ ๊ฒฝ๊ตฌ ์—ฐ์‡„์ƒ๊ตฌ๊ท ์ธ S. gordonii์˜ ์„ฑ์žฅ์„ ์–ต์ œํ•  ์ˆ˜ ์žˆ์Œ์„ ๋ณด์—ฌ์ฃผ์—ˆ๋‹ค. ๊ทธ ์ค‘ propionate๊ฐ€ ๊ฐ€์žฅ ๊ฐ•ํ•˜๊ฒŒ S. gordonii์˜ ์„ฑ์žฅ์„ ์–ต์ œํ•˜์˜€๋‹ค. Propionate๋Š” S. gordonii๋ฟ๋งŒ ์•„๋‹ˆ๋ผ ๋‹ค๋ฅธ ๊ตฌ๊ฐ•์—ฐ์‡„์ƒ๊ตฌ๊ท ์˜ ์„ฑ์žฅ์„ ์–ต์ œํ•  ์ˆ˜ ์žˆ๊ณ  ์ด๋Ÿฌํ•œ ์–ต์ œ ํšจ๊ณผ๊ฐ€ ๋‹ค์–‘ํ•œ ์„ฑ์žฅ ์ƒํƒœ์— ๋”ฐ๋ผ ๋‹ฌ๋ผ ์งˆ ์ˆ˜ ์žˆ์Œ์„ ๋ณด์—ฌ์ฃผ์—ˆ๋‹ค. ๋˜ ์ด๋Ÿฌํ•œ ํŠน์ง•์€ ์‹ค์ œ ํ™˜์ž์—์„œ ๋ถ„๋ฆฌ๋œ ๊ท ์ฃผ์—์„œ๋„ ๋™์ผํ•˜๊ฒŒ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ๊ตฌ๊ฐ• ์—ฐ์‡„์ƒ๊ตฌ๊ท ์˜ ์ƒ๋ฌผ๋ง‰ ํ˜•์„ฑ์— ์žˆ์–ด์„œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์€ ๋‹ค์–‘ํ•œ ํšจ๊ณผ๋ฅผ ๋ณด์˜€๋‹ค. S. gordonii ์ƒ๋ฌผ๋ง‰ ์–ต์ œ์—์„œ๋Š” ์ฟผ๋Ÿผ์„ผ์‹ฑ ์ธ์ž๋ฅผ ์–ต์ œํ•˜์˜€๋‹ค. ๋”ฐ๋ผ์„œ ๋‹จ์‡„์ง€๋ฐฉ์‚ฐ์€ ๊ฒฝ๊ตฌ ์—ฐ์‡„์ƒ๊ตฌ๊ท ์— ์„ฑ์žฅ๊ณผ ์ƒ๋ฌผ๋ง‰ํ˜•์„ฑ์˜ ์ €ํ•ด์ œ๋กœ์„œ ์‚ฌ์šฉ๋  ์ˆ˜ ์žˆ์„ ๊ฒƒ์ด๋ผ๊ณ  ์˜ˆ์ƒ๋œ๋‹ค.Objectives Oral streptococci are facultative anaerobic and gram-positive bacteria that contribute to oral diseases such as tooth decay and periodontal disease through their adhesion and biofilm-forming ability to the teeth and gum. The currently-available methods to remove bacteria or biofilm often accompany various adverse effects including increased antibiotic resistance, soft tissue damage, reduced tooth strength, and taste alterations implicating the need for an alternative, safe microbial control method. Short-chain fatty acids (SCFAs) such as acetate, propionate, or butyrate are metabolites produced by carbohydrate fermentation of commensal bacteria in the gut, and recent studies have shown that they can inhibit the growth of intestinal pathogens and modulate immune responses. However, the effects of SCFAs on oral streptococci are poorly understood. The purpose of this study was to investigate the effects of SCFAs, acetate, propionate, and butyrate, on biofilm formation and growth of oral streptococci under various conditions mimicking oral environment. Methods Streptococcus gordonii was incubated in the presence or absence of various concentrations of SCFAs (acetate, propionate, and butyrate) under aerobic versus anaerobic and static versus shaking culture conditions. The bacterial growth was determined by measuring the optical density at 600 nm. The minimum inhibitory concentration/minimum bactericidal concentration test was performed under various conditions to investigate if propionate had bactericidal or bacteriostatic effects. The inhibitory effect of propionate on other oral streptococci was also investigated. On the other hand, the effect of SCFAs on the biofilm formation of various oral streptococci was examined by culturing in the presence of various concentration of SCFAs under aerobic static condition for 24 h. The biofilm formation was examined by a crystal violet assay. To determine the underlying mechanism of SCFAs on biofilm formation, S. gordonii was incubated with SCFAs in the presence of absence of AI-2 inhibitor which blocks its quorum sensing, and its mRNA expression was determined using real-time PCR. Results Of the SCFAs tested in this study, propionate most potently inhibited the growth of S. gordonii under anaerobic conditions. Propionate inhibited the growth of S. gordonii with bacteriostatic effect. The growth of five S. gordonii clinical isolates was potently inhibited by propionate under anaerobic conditions. The inhibitory effect of propionate on oral streptococci was dependent on the growth conditions. S. sanguinis and S. oralis were inhibited by propionate under anaerobic conditions, whereas S. sobrinus and S. mutans were inhibited under aerobic conditions. S. salivarius was inhibited by propionate equally in all conditions described above. Propionate most strongly affected S. mitis growth in shaking conditions. SCFAs regulated oral streptococci biofilm formation. In particular, SCFAs inhibited S. gordonii biofilm formation even at early time points, but did not affect pre-formed biofilms. SCFAs also inhibited S. gordonii competence-stimulating peptide (CSP) gene expression level. Conclusions Propionate potently inhibited the growth of S. gordonii under anaerobic conditions. In addition, propionate inhibited the growth of all oral streptococci and the degree of inhibition was dependent on growth conditions. Among the oral streptococci, SCFAs most potently inhibited S. gordonii biofilm. Moreover, acetate inhibited S. gordonii biofilm through inhibition of CSP. Collectively, SCFAs may have the potential as a biocompatible anti-bacterial or anti-biofilm agent for the control of oral streptococci.Chapter I. Introduction 1 Chapter II. Materials and Methods 5 2.1 Reagent and chemicals 5 2.2 Bacteria strains and culture conditions 5 2.3 Bacterial growth and biofilm formation 6 2.4 Minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) test 8 2.5 Real-time PCR 8 2.6 Statistical analysis 11 Chapter III. Results 12 3.1 The growth of S. gordonii is inhibited by SCFAs under anaerobic condition 12 3.2 Propionate most potently inhibits the growth of S. gordonii clinical isolates under anaerobic condition18 3.3 Growth condition determines the growth inhibition by propionate on oral streptococci 21 3.4 SCFAs inhibit S. gordonii biofilm formation 24 3.5 SCFAs inhibit S. gordonii biofilm formation at early time point and do not affect the disruption of biofilm 28 3.6 Acetate inhibits S. gordonii biofilm formation via inhibition of CSP 31 Chapter IV. Discussion 35 Chapter V. References 38 ๊ตญ๋ฌธ์ดˆ๋ก 43์„

    A Study on the profit improvement against the business of container terminal operation

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    Supply excess caused by opening the New Port in Busan has brought the fierce competition between container terminal operators to keep the more volume, which resulted container terminal operators to be faced with serious financial difficulties through competitively lowering the prices especially for terminal operators in the north port. The competitiveness for the north port has been getting worse due to the deteriorated facilities as well as the lower depth of water below 16 meters, therefore the volume has been also continuously moving out to the new port. The container volume in Busan port has ranked 5th in the world until 2013, however Busan port dropped to 6th placer behind Ningbo-Zhoushan port in China in 2014. Now the serious consideration to protect the port industry as a national industry is desperately in need. The purpose of this paper is to review the status of the serious deficit that north port is currently facing, and to suggest 5 alternatives to overcome the financial troubles in north port as below. First is the port concentration by container terminal operatorsโ€™ integration. The grand integration with many small sized terminal operators is expected to improve the competitiveness and profitability through the economy of scale. Actually there have been already 2 integrations in the north port, one is the newly consolidated company of BIT(Busan International Terminal) in December 2013, and the other is KBCT merging with UTC in January 2014. Second is the functional change in Busan port. New port is specialized for mega container ships by the most modern facilities together with the sufficient depth of water over 16 meters while the north port is focused on the small & medium sized ships as feeder vessels for intra Asia. North port is also to be developed as a hub port for transshipment by well connecting new port and north port. Third is the reintroduction of tariff approval system. The tariff in the north port has been seriously dropped due to the fierce competition between container terminal operators to keep the more volume. The price at about krw100K/TEU in 2004 has been decreased into around krw45K/TEU in 2014. The price in Singapore, Shanghai and Ningbo is currently over krw100K/TEU, and it is even at krw178K/TEU in Yokohama Japan which are all much above the price in Korea. Therefore, to minimize the price gap, tariff approval system is urgently necessary by setting the legal basis forcing container terminal operators to keep the approved price strictly without a price cutting competition, and then the tariff is to be gradually stabilizing. Forth is change the fixed rental system into volume based rental. This may mitigate the excessive competition, and then eventually stop the container terminal operatorsโ€™ competitively lowering the prices. Lastly, flexibility in port manpower structure. The strong competition for container terminal operators comes from the competitive cost structure as well as the qualified service which are all brought under the circumstance of good allocation of manpower by the flexibility of manpower structure.์ œ1์žฅ ์„œ ๋ก  1 ์ œ1์ ˆ ์—ฐ๊ตฌ์˜ ๋ฐฐ๊ฒฝ๊ณผ ๋ชฉ์  1 1. ์—ฐ๊ตฌ์˜ ๋ฐฐ๊ฒฝ 1 2. ์—ฐ๊ตฌ์˜ ๋ชฉ์  2 ์ œ2์ ˆ ์—ฐ๊ตฌ์˜ ๋ฐฉ๋ฒ•๊ณผ ๊ตฌ์„ฑ 3 1. ์—ฐ๊ตฌ์˜ ๋ฐฉ๋ฒ• 3 2. ์—ฐ๊ตฌ์˜ ๊ตฌ์„ฑ 3 ์ œ2์žฅ ์ปจํ…Œ์ด๋„ˆ ํ„ฐ๋ฏธ๋„ ํ˜„ํ™ฉ ๋ถ„์„ 4 ์ œ1์ ˆ ๊ตญ๋‚ด ์ปจํ…Œ์ด๋„ˆ ํ„ฐ๋ฏธ๋„์˜ ์šด์˜ ํ˜„ํ™ฉ 4 1. ๊ตญ๋‚ด ์ฃผ์š” ๊ตญ๋‚ด ์ปจํ…Œ์ด๋„ˆ ํ„ฐ๋ฏธ๋„ ํ˜„ํ™ฉ 4 2. ๊ตญ๋‚ด ์ฃผ์š” ํ•ญ๋งŒ์˜ ๋ฌผ๋™๋Ÿ‰ ์ถ”์ด 11 3. ๋ถ€์‚ฐ ์‹ ํ•ญ ๋ฐ ๋ถํ•ญ์˜ ๋ฌผ๋™๋Ÿ‰๊ณผ ์‹œ์žฅ ์ ์œ ์œจ ์ถ”์ด 12 ์ œ2์ ˆ ๋ถ€์‚ฐํ•ญ ์ปจํ…Œ์ด๋„ˆ ํ„ฐ๋ฏธ๋„์˜ ์žฌ๋ฌด์ž๋ฃŒ ๋ถ„์„ 14 1. ๋ถ€์‚ฐํ•ญ ์ „์ฒด (์‹ ํ•ญ ๋ฐ ๋ถํ•ญ) 17 2. ๋ถํ•ญ ์ปจํ…Œ์ด๋„ˆํ„ฐ๋ฏธ๋„ ์šด์˜์‚ฌ 37 3. ์‹ ํ•ญ ์ปจํ…Œ์ด๋„ˆํ„ฐ๋ฏธ๋„ ์šด์˜์‚ฌ 56 ์ œ3์žฅ ์ปจํ…Œ์ด๋„ˆ ํ„ฐ๋ฏธ๋„์˜ ์ˆ˜์ต์„ฑ ๊ฐœ์„  ๋ฐฉ์•ˆ 82 ์ œ1์ ˆ ์ปจํ…Œ์ด๋„ˆํ„ฐ๋ฏธ๋„ ํ†ตํ•ฉ ์šด์˜(Consolidation) 82 ์ œ2์ ˆ ๋ถ€์‚ฐ ํ•ญ๋งŒ์˜ ๊ธฐ๋Šฅ ์ „ํ™˜ 84 ์ œ3์ ˆ ์š”์œจ์ธ๊ฐ€์ œ (Tariff approval system) 85 ์ œ4์ ˆ ๊ณ ์ • ์ž„๋Œ€๋ฃŒ์ œ์˜ ๋ฌผ๋Ÿ‰ ์—ฐ๋™์ œ ์ „ํ™˜ 88 ์ œ5์ ˆ ํ•ญ๋งŒ์ธ๋ ฅ๊ตฌ์กฐ ์œ ์—ฐ์„ฑ ํ™•๋ณด 90 ์ œ4์žฅ ๊ฒฐ๋ก  91 ์ œ1์ ˆ ์—ฐ๊ตฌ๊ฒฐ๊ณผ์˜ ์š”์•ฝ 91 ์ œ2์ ˆ ์—ฐ๊ตฌ์˜ ํ•œ๊ณ„์  ๋ฐ ํ–ฅํ›„ ๊ณผ์ œ 92 ์ฐธ๊ณ ๋ฌธํ—Œ 9

    Discovery of novel acetylcholinesterase inhibitors through integration of machine learning with genetic algorithm based in silico screening approaches

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    Introduction: Alzheimer's disease (AD) is the most studied progressive eurodegenerative disorder, affecting 40-50 million of the global population. This progressive neurodegenerative disease is marked by gradual and irreversible declines in cognitive functions. The unavailability of therapeutic drug candidates restricting/reversing the progression of this dementia has severed the existing challenge. The development of acetylcholinesterase (AChE) inhibitors retains a great research focus for the discovery of an anti-Alzheimer drug. Materials and methods: This study focused on finding AChE inhibitors by applying the machine learning (ML) predictive modeling approach, which is an integral part of the current drug discovery process. In this study, we have extensively utilized ML and other in silico approaches to search for an effective lead molecule against AChE. Result and discussion: The output of this study helped us to identify some promising AChE inhibitors. The selected compounds performed well at different levels of analysis and may provide a possible pathway for the future design of potent AChE inhibitors.ope

    Functional Unit Allocation for Low Power Design

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    Maste

    ็ดซๅค–็ทš้Ž้…ธๅŒ–ๆฐด็ด ่™•็†๋ฅผ ์ด์šฉํ•œ Parathion์˜ ้™คๅŽป์— ๊ด€ํ•œ ๅฏฆ้ฉ—็š„ ็ก็ฉถ

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    ํ•™์œ„๋…ผ๋ฌธ(์„์‚ฌ)--์„œ์šธๅคงๅญธๆ ก ๅคงๅญธ้™ข :ๅœŸๆœจๅทฅๅญธ็ง‘ ้ƒฝๅธ‚ๅทฅๅญธๅฐˆๆ”ป,1997.Maste

    ็—”็–พ ๆฒป็™‚๋ฅผ ็›ฎ็š„์œผ๋กœ ํ•œ ็ฒ˜่†œ ้™„็€ๆ€ง ๋ฐ ๆบซๅบฆ ๆ„Ÿๆ‡‰ๆ€ง ์ ค ่ฃฝๅŠ‘์˜ ้–‹็™ผ๊ณผ in vitro ์—์„œ์˜ ็‰นๆ€ง ่ฉ•ๅƒน

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    Thesis(master`s)--์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› :์ œ์•ฝํ•™๊ณผ ๋ฌผ๋ฆฌ์•ฝํ•™์ „๊ณต,2005.Maste

    ๋ฐฑ์„œ์˜ ํšก๋ณต์ง๊ทผ ํ”ผํŒ ์ƒ์กด์— ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ A๊ฐ€ ๋ฏธ์น˜๋Š” ์˜ํ–ฅ

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    Dept. of Medicine/๋ฐ•์‚ฌThe transverse rectus abdominis musculocutaneous (TRAM) flap is widely used in various reconstructive surgeries. Recent evidence suggests a positive effect of botulinum toxin A (BoTA) on flap survival. In this study, we hypothesized that pretreatment with BoTA augments axial-pattern TRAM flap survival in the presence of a vertical midline scar. We further hypothesized that this was due to increased angiogenesis resulting from enhanced activity of the hypoxia-inducible factor (HIF)-1ฮฑ/vascular endothelial growth factor (VEGF) pathway. Twenty-four Sprague-Dawley rats were randomly divided into 2 groups. Five days after creating vertical midline incisions, the BoTA group was pretreated with BoTA; the control group was similarly pretreated with normal saline. Ten days after the initial incision, the TRAM flaps were harvested. The final flap survival percentage, overall histologic changes, pedicle lumen areas, and microvessel densities were assessed on postoperative day 5. Quantitative reverse-transcription polymerase chain reaction and Western blotting were performed to evaluate angiogenesis-related factors, including cluster of differentiation 34 (CD34), HIF-1ฮฑ, and VEGF expression. Flap survival was significantly higher in the BoTA group than in the control group on both the ipsilateral (91.27 ยฑ 10.1% vs 67.91 ยฑ 20.2%; p = 0.002) and contralateral (53.16 ยฑ 19.2% vs 14.54 ยฑ 8.1%; p < 0.001) sides. In the BoTA group, a significant increase in the pedicle lumen area was observed, relative to that in the control group (p < 0.001). In the control group, mild to moderate epidermal necrosis was seen, and the microvessels were relatively small, compared with those in the BoTA group. Immunohistochemically, the numbers of CD31-positive vessels were significantly higher on the contralateral sides in the control group than in the BoTA group (p < 0.001). The relative expression of CD34 and VEGF mRNA was higher in the BoTA group than in the control group, in every zone; the relative expression of HIF-1ฮฑ mRNA was significantly higher in the BoTA group than in zone IV. The relative expression of CD34, VEGF, and HIF-1ฮฑ proteins was higher in the BoTA group than in the control group, in every zone. In conclusion, we showed that presurgical BoTA treatment might increase inferior-based TRAM flap survival due to increased HIF-1ฮฑ/VEGF-dependent angiogenesis. ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ๋ฐฑ์„œ์˜ ํšก๋ณต์ง๊ทผ ํ”ผํŒ ๋ชจ๋ธ์— ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ A๋ฅผ ๊ตญ์†Œ ์ ์šฉํ•˜์˜€์„ ๋•Œ ํ˜ˆ๊ด€ ํ™•์žฅ ๋ฐ ํ˜ˆ๊ด€ ์‹ ์ƒ ๊ด€๋ จ ์„ฑ์žฅ์ธ์ž์˜ ๊ณผ๋ฐœํ˜„์„ ํ†ตํ•ด ํšก๋ณต์ง๊ทผ ํ”ผํŒ ์ƒ์กด์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์„ ๊ทœ๋ช…ํ•˜๊ณ ์ž ํ•˜์˜€๋‹ค. 24๋งˆ๋ฆฌ์˜ ๋ฐฑ์„œ๋ฅผ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ๊ตญ์†Œ ํˆฌ์—ฌ๊ตฐ๊ณผ ์ƒ๋ฆฌ์‹์—ผ์ˆ˜๋ฅผ ํˆฌ์—ฌํ•  ๋Œ€์กฐ๊ตฐ์œผ๋กœ ๋‚˜๋ˆ„์—ˆ๋‹ค. ๋จผ์ € ๋ณต๋ถ€์˜ ์นผ๋Œ๊ธฐ ์งํ•˜๋ฐฉ์—์„œ 5cm๊ธธ์ด์˜ ์ง์„  ์ ˆ๊ฐœ์„ ์„ ๊ฐ€ํ•˜๊ณ  ๋ด‰ํ•ฉ ์‹œํ–‰ 5์ผ ํ›„์— ์‹คํ—˜๊ตฐ์€ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ A๋ฅผ ๊ตญ์†Œ ํˆฌ์—ฌํ•˜๊ณ  ๋Œ€์กฐ๊ตฐ์—์„œ๋Š” ๊ฐ™์€ ์–‘์˜ ์ƒ๋ฆฌ ์‹์—ผ์ˆ˜๋ฅผ ํˆฌ์—ฌํ•˜์˜€๋‹ค. ์ฃผ์‚ฌ 5์ผ ํ›„์— ํšก๋ณต์ง๊ทผ ํ”ผํŒ์„ ๊ฑฐ์ƒํ•˜์˜€๋‹ค. ํ”ผํŒ์„ ๊ฑฐ์ƒํ•œ ํ›„ ํ•˜๋ฐฉ์— ์‹ค๋ฆฌ์ฝ˜ ์‹œํŠธ๋ฅผ ์ ์šฉํ•œ ํ›„ ํ”ผํŒ์„ ์›๋ž˜ ์œ„์น˜๋กœ ๋‹ค์‹œ ์œ„์น˜์‹œํ‚ค๊ณ  ํ”ผํŒ์˜ ์ƒ์กด๋ฉด์ ์„ ์ˆ  ํ›„ ์ œ1์ผ, ์ œ3์ผ, ์ œ5์ผ์งธ ์ธก์ •ํ•˜์˜€๊ณ  ์ตœ์ข… ํ”ผํŒ ์ƒ์กด๋ฉด์ ์€ ์ˆ  ํ›„ 5์ผ์งธ ์ธก์ •ํ•˜์˜€๋‹ค. ํ—ค๋งˆํ†ก์‹ค๋ฆฐ-์—์˜ค์‹ ์—ผ์ƒ‰์„ ํ†ตํ•ด ํšก๋ณต์ง๊ทผ ํ”ผํŒ์˜ ํ˜ˆ๊ด€๊ฒฝ ๋ฉด์ ์˜ ๋ณ€ํ™” ๋ฐ ์ „์ฒด์ ์ธ ์กฐ์งํ•™์  ๋ณ€ํ™”์˜ ์–‘์ƒ, CD31 ๋ฉด์—ญ ํ™”ํ•™ ์—ผ์ƒ‰๋ฒ•์„ ํ†ตํ•ด ํ”ผํŒ ๋‚ด ๋ฏธ์„ธํ˜ˆ๊ด€๋†๋„๋ฅผ ๊ฐ๊ฐ ์ˆ  ํ›„ 5์ผ์งธ ํ‰๊ฐ€ํ•˜์˜€๋‹ค. ๊ทธ๋ฆฌ๊ณ  ๊ฐ™์€ ์‹œ๊ธฐ์— ํ˜ˆ๊ด€์‹ ์ƒ์— ๊ด€์—ฌํ•˜๋Š” ์ธ์ž์ธ CD34, HIF-1ฮฑ, VEGF์˜ ์œ ์ „์ž ๋ฐ ๋‹จ๋ฐฑ์งˆ์„ ์ •๋Ÿ‰์ ์œผ๋กœ ์ธก์ •ํ•˜์˜€๋‹ค. ์ƒ์กดํ”ผํŒ ๋ฉด์  ๋ถ„์„์—์„œ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์ด ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•˜์—ฌ ํ†ต๊ณ„์ ์œผ๋กœ ์œ ์˜ํ•˜๊ฒŒ ๋†’์€ ํ”ผํŒ ์ƒ์กด๋ฅ ์„ ๋‚˜ํƒ€๋‚ด์—ˆ๋‹ค. ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์—์„œ ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•ด ํ˜ˆ๊ด€๊ฒฝ ๋ฉด์ ์ด ์œ ์˜ํ•˜๊ฒŒ ํ™•์žฅ๋˜์–ด ์žˆ๋Š” ์†Œ๊ฒฌ์ด ๊ด€์ฐฐ๋˜์—ˆ์œผ๋ฉฐ, ๋Œ€์กฐ๊ตฐ์—์„œ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์— ๋น„ํ•ด ๊ฒฝ๋„์—์„œ ์ค‘์ฆ๋„์˜ ํ‘œํ”ผ๊ดด์‚ฌ๊ฐ€ ๊ด€์ฐฐ๋˜์—ˆ์œผ๋ฉฐ, ๋ฏธ์„ธํ˜ˆ๊ด€๋„ ์œ„์ถ•๋˜์–ด ์žˆ๋Š” ์†Œ๊ฒฌ์„ ๋ณด์˜€๋‹ค. ๋ฏธ์„ธํ˜ˆ๊ด€๋ฐ€๋„ ์ธก์ •์—์„œ๋Š” ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์ด ๋™์ธก ๋ถ€์œ„์—์„œ๋Š” ๋†’๊ฒŒ ๋‚˜ํƒ€๋‚ฌ์ง€๋งŒ ๋‘ ๊ตฐ๊ฐ„์˜ ์œ ์˜ํ•œ ์ฐจ์ด๊ฐ€ ๋‚˜ํƒ€๋‚˜์ง€ ์•Š์•˜๋‹ค. ๋ฐ˜๋Œ€์ธก ๋ถ€์œ„์—์„œ๋Š” ์˜คํžˆ๋ ค ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์—์„œ ์œ ์˜ํ•˜๊ฒŒ ๋‚ฎ๊ฒŒ ์ธก์ •๋˜์—ˆ๋‹ค. CD34์™€ VEGF ์œ ์ „์ž ๋ฐœํ˜„์€ ๋ณดํŠค๋ฆฌ๋ˆ”ํ†ก์‹  ํˆฌ์—ฌ๊ตฐ์—์„œ ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•ด์„œ ๋Œ€๋ถ€๋ถ„ ํ†ต๊ณ„์ ์œผ๋กœ ์œ ์˜ํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•œ ์†Œ๊ฒฌ์ด ๊ด€์ฐฐ๋˜์—ˆ๋‹ค. HIF-1ฮฑ๋Š” ํ—ˆํ˜ˆ์ด ์ง„ํ–‰๋œ ์˜์—ญ IV์—์„œ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์—์„œ ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•˜์—ฌ ๋ฐœํ˜„์ด ์ฆ๊ฐ€๋˜๋Š” ๊ฒƒ์„ ๊ด€์ฐฐํ•˜์˜€๋‹ค. CD34, VEGF, HIF-1ฮฑ์˜ ๋‹จ๋ฐฑ์งˆ ๋ฐœํ˜„์€ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ ํˆฌ์—ฌ๊ตฐ์—์„œ ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•ด์„œ ํ†ต๊ณ„์ ์œผ๋กœ ์œ ์˜ํ•˜๊ฒŒ ์ฆ๊ฐ€๋˜์–ด ์žˆ๋Š” ์†Œ๊ฒฌ์„ ๋ณด์˜€๋‹ค. ๋ณธ ์—ฐ๊ตฌ๋ฅผ ํ†ตํ•ด์„œ ์ˆ ์ „ ๋ณดํˆด๋ฆฌ๋ˆ” ๋…์†Œ A๋ฅผ ๋ฐฑ์„œ์˜ ํšก๋ณต์ง๊ทผ ํ”ผํŒ ๋ชจ๋ธ์— ๊ตญ์†Œ ์ ์šฉํ•˜์˜€์„ ๋•Œ ํšก๋ณต์ง๊ทผํ”ผํŒ์˜ ํ˜ˆ๊ด€๊ฒฝ์„ ํ™•์žฅ์‹œํ‚ค๊ณ , ํ”ผํŒ๋‚ด ๋ฐ ํšก๋ณต์ง๊ทผ์˜ ํ˜ˆ๊ด€์‹ ์ƒ์ธ์ž๋ฅผ ๋Œ€์กฐ๊ตฐ์— ๋น„ํ•ด ์ฆ๊ฐ€์‹œ์ผฐ์œผ๋ฉฐ ์ด๋ฅผ ํ†ตํ•ด ์ƒ์กด๋ฉด์ ์„ ์ฆ๊ฐ€์‹œํ‚ด์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค.ope

    2013 ์ถฉ๋‚จ๊ฒฝ์ œ๊ต์œก์„ผํ„ฐ ์ „ํ†ต์‹œ์žฅ ๊ฒฝ์ œ ์•„์นด๋ฐ๋ฏธ (๋ฐ•ํƒœํ™˜)

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    - ํ™์„ฑ์ „ํ†ต์‹œ์žฅ ํ™œ์„ฑํ™” ๋ฐฉ์•ˆ ๋…ผ์˜ - ๊ฐ•์˜ ์ž๋ฃŒ๋Š” ์™ธ๋ถ€๋ฌธ๊ฑด์œผ๋กœ ๊ณต๊ฐœ๋ฅผ ์ œ์•ˆํ•ฉ๋‹ˆ๋‹ค.(๋น„๊ณต๊ฐœ) 1. ๊ฐœ์ตœ ๋ชฉ์  โ—‹ ํ™์„ฑ ์ „ํ†ต์‹œ์žฅ ์ƒ์ธ, ์ „๋ฌธ๊ฐ€, ์ถ”์ง„์œ„์›ํšŒ ๋“ฑ์ด ํ•œ ์ž๋ฆฌ์— ๋ชจ์—ฌ ํ™์„ฑ ์ „ํ†ต์‹œ์žฅ ํ™œ์„ฑํ™”๋ฅผ ์œ„ํ•œ ๋…ผ์˜์˜ ์žฅ ๋งˆ๋ จ โ—‹ ์ผ๋ฐฉ์ ์ธ ๊ฐ•์˜๋ฅผ ํ†ตํ•œ ์›Œํฌ์ˆ์ด ์•„๋‹Œ ์ฐธ์—ฌ์ž๋“ค์ด ๋ฌธ์ œ์ธ์‹ ๋‹จ๊ณ„๋ถ€ํ„ฐ ํ™œ์„ฑํ™” ๋ฐฉ์•ˆ ๋„์ถœ์˜ ๋‹จ๊ณ„๊นŒ์ง€์˜ ์‹ฌ์ธต ๋…ผ์˜ ์ง„ํ–‰ - ์ดํ›„ ์ƒ๋žต1. ํผ์‹ค๋ฆฌํ…Œ์ด์…˜(facilitation)๊ธฐ๋ฒ•์„ ์ ์šฉํ•œ ํ™์„ฑ์ „ํ†ต์‹œ์žฅ ํ™œ์„ฑํ™” ๋ฐฉ์•ˆ ๋…ผ์˜ I 2. ํผ์‹ค๋ฆฌํ…Œ์ด์…˜(facilitation)๊ธฐ๋ฒ•์„ ์ ์šฉํ•œ ํ™์„ฑ์ „ํ†ต์‹œ์žฅ ํ™œ์„ฑํ™” ๋ฐฉ์•ˆ ๋…ผ์˜ II (๋ฐ•ํƒœํ™˜ ํŒ€์žฅ ์ฟ ํผ์‹ค๋ฆฌํ…Œ์ด์…˜ ๊ทธ๋ฃน CF

    A STUDY ON THE CALCULATION METHOD OF MASS POLAR INERTIA MOMENT OF CRANKSHAFT AND RUNNING GEAR FOR RECIPROCATION ENGINES

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    The Effect of Red Ginseng Extract Intake on Ischemic Flaps

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    Red ginseng is well known for its angiogenic effects and its effect of increasing expression of vascular endothelial growth factors (VEGFs), but little experimental evidence has been published. In this study, we examined the effect of red ginseng using an ischemic flap model. Twenty male Sprague-Dawley rats were divided into two groups of 10. One group drank red ginseng solution from 7 days prior to surgery to 7 days after, whereas the other group drank distilled water. We created a local flap on the back of each rat. We analyzed the surviving area of the flap for 10 days after surgery and measured the blood flow of the flap. Ten days after the operation, CD31-positive vessels and VEGF expression were examined by immunohistochemistry. The percentages of surviving areas of the flap were 76 ยฑ 3% for the experimental group and 39 ยฑ 5% for the control group (P = 0.0002). Blood flow in the experimental group increased for 10 days after the surgery. The number of newly generated capillaries in the experimental group was 14.0 ยฑ 3.5, which was significantly higher than 5.7 ยฑ 1.9 in the control group. The expression of VEGF in the experimental group was significantly higher than in the control group (p = 0.0003). Administration of red ginseng extract increases the survival of ischemic flaps via angiogenesis and elevated blood flow. Further clinical studies are warranted to apply the effect shown in this current investigation to various ischemic conditions.restrictio
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