8 research outputs found

    (An) Experimental study on the effects of cis-platinum on the buccal pouch and the salivary gland in the hamster with

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    ์น˜์˜ํ•™๊ณผ/์„์‚ฌ[ํ•œ๊ธ€] ์ €์ž๋Š” 0.5% DMBA๋ฅผ ์ฃผ 3ํšŒ ํ˜‘๋‚ญ์— 12์ฃผ๊ฐ„ ๋„ํฌํ•˜์—ฌ ์ƒํ”ผ์•”์ด ์œ ๋ฐœํ•œ 18๋งˆ๋ฆฌ๋ฅผ ์‹คํ—˜๊ตฐ์œผ๋กœ, ์ •์ƒ์ธ 18๋งˆ๋ฆฌ๋ฅผ ๋Œ€์กฐ๊ตฐ์œผ๋กœ ํ•˜์—ฌ ์‹คํ—˜๊ตฐ๊ณผ ๋Œ€์กฐ๊ตฐ ๊ณตํžˆ ABIPLATIN์„ ์ฒดํ‘œ๋ฉดใŽก ๋‹น50ใŽŽ์”ฉ ๋ณต๊ฐ•๋‚ด ์ฃผ์‚ฌํ•˜์—ฌ ABIPLATIN ํˆฌ์—ฌ์ „ ๋ฐ ํˆฌ์—ฌํ›„ 1,2,3,4,5์ฃผ์งธ ์•”์กฐ์ง ๋ฐ ํ˜‘๋‚ญ์ ๋ง‰๊ณผ ์ดํ•˜์„ ์„ ์ ์ถœํ•˜์—ฌ ํ†ต๋ฒ•์— ๋”ฐ๋ผ Hematoxylin-Eosin ์ค‘์—ผ์ƒ‰๊ณผ Periodic acid Schiff ์—ผ์ƒ‰ํ•˜์—ฌ ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ฒฐ๋ก ์„ ์–ป์—ˆ๋‹ค. 1. ๋Œ€์กฐ๊ตฐ์˜ ํ˜‘๋‚ญ์ ๋ง‰๊ณผ ์ดํ•˜์„ ์€ ๊ฒฝ์‹œ์  ๋ณ€ํ™”์—†์ด ์ •์ƒ์ ์ธ ์กฐ์ง์ƒ์„ ๋ณด์˜€๋‹ค. 2. ์‹คํ—˜๊ตฐ์˜ 1์ฃผ์งธ ํ˜‘๋‚ญ์ ๋ง‰์˜ ์•”์กฐ์ง ๋ถ€์œ„๋Š” ์•ฝ์ œ ํˆฌ์—ฌ์ „ ๋ณด๋‹ค ๊ฐํ‡ด๋œ ์ข…์–‘์˜ ์ฆ์‹์ƒ์„ ๋ณด์˜€์œผ๋‚˜ 2์ฃผ์งธ ๋ถ€ํ„ฐ๋Š” ์ ์ฐจ ์ƒํ”ผ์˜ ์ดํ˜•์„ฑ์ด ์‹ฌํ•ด์ง€๋ฉฐ ์‹ฌํ•œ ์ฆ์‹์ƒ์„ ๋ณด์ธ๋‹ค. 3. ์‹คํ—˜๊ตฐ์˜ ์•ฝ์ œ ํˆฌ์—ฌ์ „ ์ดํ•˜์„ ์˜ ์†์ƒ์€ ์•”์กฐ์ง์˜ ์ฆ์‹์ƒ์— ๋”ฐ๋ฅธ ์กฐ์ง์˜ ๋ณ€์„ฑ๊ณผ ์—ผ์ฆ์˜ ํŒŒ๊ธ‰์— ๊ธฐ์ธํ•˜๋Š” ๊ฒƒ์œผ๋กœ ์‚ฌ๋ฃŒ๋œ๋‹ค. 4. ์‹คํ—˜๊ตฐ์˜ ์ดํ•˜์„ ์€ ์•ฝ์ œ ํˆฌ์—ฌ 1์ฃผ์งธ ํšŒ๋ณต์ƒ์„ ๋ณด์—ฌ 2์ฃผ์งธ ๋ถ€ํ„ฐ๋Š” ์ •์ƒ ์†Œ๊ฒฌ์ด์—ˆ์œผ๋‚˜ 5์ฃผ์งธ ๊นŒ์ง€๋„ ๋ถ€๋ถ„์ ์ธ ์„ ์„ธํฌ์˜ ์ฆ์‹์ƒ์„ ๋ณด์˜€๋‹ค. 5. PAS๋ฐ˜์‘์—์„œ ๋Œ€์กฐ๊ตฐ์˜ ํ˜‘๋‚ญ์ ๋ง‰๊ณผ ์ดํ•˜์„ ์€ ์ •์ƒ์ ์ธ ๋ฐ˜์‘์„ ๋ณด์˜€๋‹ค. 6. PAS๋ฐ˜์‘์—์„œ ์‹คํ—˜๊ตฐ์˜ ์ ๋ง‰์—์„œ ์ƒํ”ผ์ธต์€ ๋ถˆ๊ทœ์น™ํ•˜๋‚˜ ์•…์„ฑ๋„๊ฐ€ ์‹ฌํ•ด์งˆ์ˆ˜๋ก ๋น„๋ก€ํ•˜์—ฌ ์Œ์„ฑ๋ฐ˜์‘์„ ๋ณด์˜€์œผ๋ฉฐ ๊ฐ„์งˆ์กฐ์ง์—์„œ ์„ฌ์œ ํ™” ๋ถ€๋ถ„์€ ๊ฐ•์–‘์„ฑ์„ ๋ณด์˜€๋‹ค. 7. PAS๋ฐ˜์‘์—์„œ ์‹คํ—˜๊ตฐ์˜ ์•ฝ์ œ ํˆฌ์—ฌ ์ „ ์ดํ•˜์„ ์˜ ์„ ํฌ๋Š” ๋ถˆ๊ทœ์น™ํ•œ ๋ฐ˜์‘์„ ๋ณด์ด๋‚˜ ๊ธฐ์ €๋ง‰๊ณผ ๋„๊ด€์ƒํ”ผ๋Š” ๋Œ€์กฐ๊ตฐ๊ณผ ์ฐจ์ด ์—†์—ˆ์œผ๋ฉฐ ํˆฌ์—ฌํ›„ 1์ฃผ์งธ ๋ถ€ํ„ฐ ์„ ํฌ๋„ ํšŒ๋ณต์ƒ์„ ๋ณด์ด๊ธฐ ์‹œ์ž‘ํ•˜์—ฌ 3์ฃผ์งธ ๋ถ€ํ„ฐ ์ •์ƒ์†Œ๊ฒฌ๊ณผ ๋ณ„์ฐจ ์—†์—ˆ๋‹ค. [์˜๋ฌธ] This study was undertaken to observe the effects of sis-Platinum on the buccal pouch and parotid gland in the hamster with DMBA-induced oral carcinoma. 36 golden Syrian hamsters-7 week of age, about 100 gram of body weight-were used in this study. Eighteen hamsters, induced epidermoid carcinoma in the buccal pouch by painting 0.5% DMBA 3 times a week for 12 weeks served as experimental group and another eighteen sound hamsters as control group. Both the fifteen experimental & control group were injected intraperitoneally 50mg of cisplatinum per ใŽก of body surface with single dose respectively. The hamsters were sacrificed before administration and 1st, 2nd, 3rd, 4th, 5th week after administration of cis-platinum. The buccal pouch and parotid gland were excised and processed in a routine manner for Hematoxylin-Eosin and periodic acid Shiff stain. After microscopic observation following results were obtained 1. The buccal pouches & carotid glands of control group revealed normal histologic findings without periodic changes. 2. In experimental group, the neoplastic region on buccal pouch in first week showed microscopically more reduced proliferative findings than before administration of cis-Platinum, but epithelial dysplasia and proliferation were gradually developed from the 2nd week. 3. Damage on the parotid gland tissues of experimental group before administration of cia-platinum may be construed due to application on the excessive area with DMBA, diffusion of the inflammation and degeneration of tissue by tumor. 4. In the experimental group, the carotid glands began to recover from 1st week after administration of cis-Platinum and showed normal histological findings in the 2nd week, but remained partial acidic cell proliferation until the 5th week. 5. In PAS reaction, the buccal pouches and parotid glands of control group showed normal reaction without periodic change. 6. In PAS reaction, epithelial layer of the buccal pouch associated with car7in7ma in the experimental group revealed irregular reaction ; more malignant, distinct negative. Fibrosis region in the stromal tissue showed strong positive reaction. 7. In PAS reaction, the acini of the parotid glands in the experimental group before administration of cis-Platinum showed irregular reaction, but began to recover from 1st week and returned to normal reaction from 3rd week after the administration, whereas the basement membrane of acini and ductal epithelium showed normal reaction without periodic change.restrictio

    ํ‰ํŒ์˜ ์ขŒ๊ตด์— ๋Œ€ํ•œ ์„ค๊ณ„๋ฏผ๊ฐ๋„ ํ•ด์„ ๋ฐ ์ตœ์ ์„ค๊ณ„

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    ํ•™์œ„๋…ผ๋ฌธ(์„์‚ฌ)--์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› :์กฐ์„ ํ•ด์–‘๊ณตํ•™๊ณผ,2004.Maste

    Studies on the alternation of influenza viral pathogenicity by co-varying NP and NA protein pair.

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    Doctor์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค๋Š” ์ž์‹ ์˜ ์œ ์ „์ฒด์˜ ํ•ญ์›๋Œ€๋ณ€์ด (antigenic shift)์™€ ํ•ญ์›์†Œ๋ณ€์ด (antigenic drift)๋ฅผ ํ†ตํ•ด ์ž์‹ ์˜ ๋ณต์ œ ๋ฐ ํ•ญ๋ฐ”์ด๋Ÿฌ์Šค ๋ฐ˜์‘์— ๋Œ€ํ•œ ์ €ํ•ญ์„ฑ์„ ๋ณ€ํ™”์‹œํ‚จ๋‹ค. ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค์˜ ์œ ์ „์  ๋ณ€์ด์— ์˜ํ•ด 1918๋…„, 1968๋…„, ๊ทธ๋ฆฌ๊ณ  2009๋…„์— ๋Œ€์œ ํ–‰ ์ธํ”Œ๋ฃจ์—”์ž๋ฅผ ์œ ๋ฐœํ•˜์˜€์œผ๋ฉฐ, ๋งŽ์€ ์—ฐ๊ตฌ๋“ค์€ ์ด๋Ÿฌํ•œ ๋Œ€์œ ํ–‰ ์ธํ”Œ๋ฃจ์—”์ž์˜ ๊ฐ•ํ•œ ๋ณ‘์›์„ฑ์˜ ์›์ธ์„ ๋ฐ”์ด๋Ÿฌ์Šค ๋‹จ๋ฐฑ์งˆ ๋ถ„์„์„ ํ†ตํ•ด ์ฐพ๊ณ ์ž ํ•˜์˜€๋‹ค. ๋‹ค์ˆ˜์˜ ์—ฐ๊ตฌ๋Š” ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค ๋‹จ์ผ ๋‹จ๋ฐฑ์งˆ์˜ ํŠน์ • ์ž”๊ธฐ ๋Œ์—ฐ๋ณ€์ด๊ฐ€ ๋ฐ”์ด๋Ÿฌ์Šค์˜ ๋ณต์ œ ๋˜๋Š” ์ˆ™์ฃผ์˜ ๋ฉด์—ญ ๋ฐ˜์‘์„ ์กฐ์ ˆ ํ•˜๋Š” ๊ฒƒ์ด ์—ฐ๊ตฌ ๋˜์–ด ์™”๋‹ค. ํ•˜์ง€๋งŒ, ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค๋Š” 11๊ฐœ์˜ ๋ฐ”์ด๋Ÿฌ์Šค ๋‹จ๋ฐฑ์งˆ๋กœ ์ด๋ฃจ์–ด์ ธ์žˆ์œผ๋ฉฐ, ๋ฐ”์ด๋Ÿฌ์Šค ๋ณต์ œ๋ฅผ ์œ„ํ•ด ๋‹ค์ˆ˜ ๋‹จ๋ฐฑ์งˆ ๊ฐ„์˜ ๋„คํŠธ์›Œํฌ๊ฐ€ ํ˜•์„ฑ๋˜์–ด ๋‹ค์œ ์ „์ (multigenic)์˜ ํŠน์ง•์„ ๋ณด์—ฌ์ค€๋‹ค. ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค์˜ ๋ณ‘์›์„ฑ์— ๋Œ€ํ•œ ๋‹ค์œ ์ „์ ์ธ ํšจ๊ณผ๋ฅผ ์•Œ์•„๋ณด๊ธฐ ์œ„ํ•ด, ๊ธฐ๋Šฅ์ ์œผ๋กœ ์—ฐ๊ด€๋œ ๋ฌผ์งˆ๋“ค์€ ํ•˜๋‚˜์˜ ๋ฌผ์งˆ ๋ณ€ํ™”์— ์˜ํ•ด ๋‹ค๋ฅธ ๋ฌผ์งˆ๋„ ๋ณ€ํ™”ํ•œ๋‹ค๋Š” ๊ณต๋ณ€ํ™” ์ปจ์…‰์„ ์ด์šฉํ•˜์˜€๋‹ค. 2009๋…„ H1N1 ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค์˜ ๋ณ‘์›์„ฑ์— ๊ด€์—ฌํ•˜๋Š” ์œ ์ „์ ์ธ ํŠน์ง•์„ ์ฐพ๊ธฐ ์œ„ํ•ด, 417๊ฐœ์˜ 2009๋…„ H1N1 ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค ์ŠคํŠธ๋ ˆ์ธ์˜ ์œ ์ „์ •๋ณด๋ฅผ ์ด์šฉํ•˜์—ฌ, 10๊ฐœ์˜ ๋ฐ”์ด๋Ÿฌ์Šค ๋‹จ๋ฐฑ์งˆ ๊ฐ„์˜ ๊ณต๋ณ€ํ™”์œจ์„ ํ—ˆ๊ณ„์—ฐ ๋ฐ•์‚ฌ์˜ ๋„์›€์œผ๋กœ ์ธก์ •ํ•˜์˜€๋‹ค. 45๊ฐœ์˜ ์กฐํ•ฉ ์ค‘ NP์™€ NA ๋‹จ๋ฐฑ์งˆ ์กฐํ•ฉ์ด ๊ฐ€์žฅ ๋†’์€ ๊ณต๋ณ€ํ™” ๊ฐ’์„ ์ธก์ • ๋˜์—ˆ์œผ๋ฉฐ, ๊ฐ๊ฐ NP์™€ NA์— ํŠน์ด์ ์ธ ์•„๋ฏธ๋…ธ์‚ฐ ์น˜ํ™˜์ด ์ด๋ฃจ์–ด์ ธ ์žˆ์—ˆ๋‹ค. NP์™€ NA ๋‹จ๋ฐฑ์งˆ์— ํŠน์ด์  ์•„๋ฏธ๋…ธ์‚ฐ ์ž”๊ธฐ(NPV100I, NAD248N)๋ฅผ ๊ฐ–๊ฒŒ๋” ์žฌ์กฐํ•ฉ ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค๋ฅผ ์ œ์ž‘์„ ํ•˜์—ฌ, ์„ธํฌ๋…์„ฑ ๋ฐ ๋ณ‘์›์„ฑ์„ ํ™•์ธํ•˜์˜€๋‹ค. ๊ทธ ๊ฒฐ๊ณผ ๋น„๊ต๊ตฐ์œผ๋กœ ์‚ฌ์šฉํ•œ ๊ฐ NP์™€ NA ๋‹จ์ผ ๋‹จ๋ฐฑ์งˆ์— ๋Œ€ํ•œ ํŠน์ด์  ์•„๋ฏธ๋…ธ์‚ฐ ์ž”๊ธฐ๋ฅผ ๊ฐ–๋Š” ์žฌ์กฐํ•ฉ ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค์— ๋น„ํ•ด ๊ฐ•ํ•œ ์„ธํฌ ์‚ฌ๋ฉธ ๋Šฅ๋ ฅ ๋ฐ ์‹ธ์ดํ† ์นด์ธ ์ƒ์‚ฐ ๋Šฅ๋ ฅ์„ ๋ณด์—ฌ์ฃผ์—ˆ์œผ๋ฉฐ, ๋™๋ฌผ๋ชจ๋ธ์—์„œ ๋™๋ฌผ์˜ ์ƒ์กด๋ฅ ์„ ๊ธ‰๊ฒฉํžˆ ๊ฐ์†Œ์‹œํ‚ค๋Š” ๊ฒƒ์„ ํ™•์ธํ•จ์œผ๋กœ์จ, NP์™€ NA ์กฐํ•ฉ์„ ๊ฐ–๋Š” ์žฌ์กฐํ•ฉ ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค๋Š” ๊ฐ•ํ•œ ๋ณ‘์›์„ฑ์„ ์ฐพ๋Š” ๊ฒƒ์„ ํ™•์ธํ•˜์˜€๋‹ค. NPV100I์™€ NAD248N ์กฐํ•ฉ์„ ๊ฐ–๋Š” ์žฌ์กฐํ•ฉ ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค์˜ ๊ฐ•ํ•œ ๋ณ‘์›์„ฑ์— ๋Œ€ํ•œ ๋ฉ”์ปค๋‹ˆ์ฆ˜์„ ํ™•์ธํ•˜๊ธฐ ์œ„ํ•ด, ๋‹จ๋ฐฑ์งˆ ๊ฐ„์ด ๊ฒฐํ•ฉ๊ณผ ๊ฐ ๋‹จ๋ฐฑ์งˆ์˜ ๊ธฐ๋Šฅ ๋ณ€ํ™”๋ฅผ ํ™•์ธํ•˜์˜€๋‹ค. NP์™€ NA์˜ ๋‹จ๋ฐฑ์งˆ ๊ฐ„ ๊ฒฐํ•ฉ์€ ์—†์—ˆ์ง€๋งŒ, NP์˜ RNA ๊ฒฐํ•ฉ ๋Šฅ๋ ฅ์€ V00I ๋Œ์—ฐ๋ณ€์ด์— ์˜ํ•ด ์ฆ๊ฐ€ํ•˜์˜€์œผ๋ฉฐ, NAD248N์ด ๊ฐ™์ด ์กด์žฌํ•˜๋Š” ์กฐ๊ฑด์—์„œ๋Š” ๋”์šฑ๋” ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ํ•œํŽธ NA๋Š” ์„ธํฌ๋ง‰์— ์กด์žฌํ•˜๋Š” ์ง€์งˆ ๋—๋ชฉ (lipid raft)๋กœ์˜ ์ด๋™์ด D248N ๋Œ์—ฐ๋ณ€์ด์— ์˜ํ•ด ์ฆ๊ฐ€ํ•˜์˜€์œผ๋ฉฐ, NPV100I ์กด์žฌ์— ์˜ํ•ด ์ง€์งˆ ๋—๋ชฉ์œผ๋กœ ์ด๋™ํ•˜๋Š” NA์–‘์€ ๋”์šฑ ๋” ์ฆ๊ฐ€ํ•˜์˜€๋‹ค. ์ง€์งˆ ๋—๋ชฉ์œผ๋กœ ๊ฐ€๋Š” NA์˜ ์–‘์„ ์กฐ์ ˆ์— ์˜ํ•ด, NP์˜ RNA ๊ฒฐํ•ฉ ๋Šฅ๋ ฅ์ด ๋ณ€ํ™” ํ•˜์˜€๋‹ค. ์ด๋Š” ์ƒˆ๋กญ๊ฒŒ ๋งŒ๋“ค์–ด์ง€๋Š” ์ธํ”Œ๋ฃจ์—”์ž A ๋ฐ”์ด๋Ÿฌ์Šค์˜ Budding์œ„ํ•ด ๊ฐ„์ ‘์ ์œผ๋กœ NP์˜ RNA ๊ฒฐํ•ฉ ๋Šฅ๋ ฅ์ด ์˜ํ–ฅ์„ ์ฃผ๊ณ  ์žˆ๋‹ค. ์ด๋ฅผ ํ†ตํ•ด, ๋ณธ ์—ฐ๊ตฌ๋Š” ๊ฐ•ํ•œ ๋ณ‘์›์„ฑ์„ ๋ณด์˜€๋˜ 2009 H1N1 ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค์˜ ์œ ์ „์ •๋ณด ๋ถ„์„์„ ํ†ตํ•ด ํš๋“ํ•œ ๊ณต๋ณ€ํ™”ํ•˜๋Š” NPV100I ์™€ NAD248N ๋‹จ๋ฐฑ์งˆ ์กฐํ•ฉ์ด ์ธํ”Œ๋ฃจ์—”์ž ๋ฐ”์ด๋Ÿฌ์Šค์˜ ์กฐ๋ฆฝ๊ณผ ๋ถ„๋น„ (assembly and release) ์ฆ๋Œ€๋ฅผ ์œ ๋ฐœํ•ด ๋ฐ”์ด๋Ÿฌ์Šค ๋ณ‘์›์„ฑ ์ฆ๊ฐ€ ์‹œํ‚จ๋‹ค๋Š” ๋ชจ๋ธ์„ ์ œ์‹œํ•˜๊ณ  ์žˆ๋‹ค.The influenza A virus changed the ability of their replication and anti-host defense system by alteration of their genomes through antigenic shift and antigenic drift. In 1918, 1968 and 2009, the influenza viral genetic variation caused a strong influenza viral pathogenicity also known as pandemic outbreak. Many studies have tried to explain where strong viral pathogenicity comes from. Based on the analysis of single viral protein mutation, scientists found the specific residues at viral proteins which regulated viral replication or host immune response. However, the influenza A viruses have 11 viral proteins, and multiple viral proteins work together for their viral replication. Therefore, it was hard to explain the viral pathogenicity through single viral protein mutation. To approach the new insight about multi-genic effect on viral pathogenicity, co-variation (co-evolution) concepts that the change in a biological object triggered by the change of a functionally related object, was adopted. To identify pairs of genetic traits that contributed to the pathogenicity of the 2009 H1N1 influenza A virus that genome sequences are available, the covariations of 10 viral proteins using sequence information obtained from 417 isolates during the 2009 pandemic were measured. Among 45 combinations, the NP and NA pair showed an exceptionally high covariance value. Specific amino acid substitutions that frequently co-occurred in the NP and NA pairs were mapped, and recombinant WSN influenza A viruses with the corresponding substitutions at each NP and NA position were generated. In contrast to individual NP or NA recombinant viruses (NPV100I NAWSN or NPWSN NAD248N), NPV100I NAD248N WSN viruses with co-varying substitutions were highly pathogenic. The recombinant NPV100I NAD248N WSN virus was lethal for BALB/c mice and was accompanied by increased viral production, cytokine and chemokine expression, and cell death. Physical interaction between NPV100I and NAD248N was not observed, and the viral RdRP activity was not altered by these substitutions. In contrast, the RNA-binding ability of the NP protein was increased by the V to I substitution at 100th residue, which was further strengthened by co-expression with the NAD248N protein. The NAD248N protein, meanwhile, was recruited more frequently within the lipid raft compartment, which indirectly affected the RNA-binding ability of the NP protein as well as viral release. Together, these data indicate that the co-varying NPV100I and NAD248N pair functions together to synergistically augment viral assembly and release, which may explain the pathogenicity of the 2009 pandemic H1N1 influenza A viru
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