• Title/Summary/Keyword: 3′-End formation

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Identification of a Regulatory Element Required for 3’-End Formation in Transcripts of rhp51$^+$, a recA Homolog of the Fission Yeast Schizosaccharomyces pombe

  • Yeun Kyu Jang
    • Animal cells and systems
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    • v.3 no.4
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    • pp.413-415
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    • 1999
  • Our previous report demonstrated that the rhp51$^+$, a recA and RAD51 homolog of the fission yeast, encodes three transcripts of 1.9, 1.6 and 1.3 kb which have at least six polyadenylation sites. The 3'-end of the gene alone can direct the formation of multiple, discrete 3'ends of the transcripts. To identify the regulatory element required for the 3'-end formation of -rhp51$^+$ deletion mapping analysis was performed. Northern blot analysis revealed that the 254-bp DNA fragment including 4 distinct poly (A) sites downstream from the Hindlll site, is crucial for normal 3'-end formation. Deletion of the 3'-terminal AU rich region caused appearance of read-through RNA, leading to enhancement of survival rate of the rhp51 deletion mutant in response to DNA damaging agent, methylmethane sulfonate (MMS). The results imply that the rhp51$^+$ system may be useful for molecular analysis of the 3'-end formation of RNA in the fission yeast.

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An Instance of Selecting Retention Chemicals Based on Simultaneous Analysis of Retention, Drainage and Formation of RDA (Retention and Drainage Analyzer) Sheets (보류, 탈수, 지합을 종합적으로 고려한 Retention and Drainage Analyzer (RDA) 활용 보류향상제의 선정사례)

  • Jeon, Chang-Hoon;Ryu, Jeong-Yong;Song, Bong-Keun;Seo, Young-Bum;Chung, Sung-Hyun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.3
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    • pp.7-13
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    • 2010
  • KOptimization and control of wet-end process provide a key solution to improve paper quality and production efficiency at the same time. Wet-end of paper machine is to determine three important influencing factors of papermaking i.e., retention, drainage and formation. Good formation of paper could be made at the cost of deteriorated retention or drainage. In the same manner increase of retention aid could cause the bad formation of paper. It is very important to find a proper retention chemical which may satisfy one of three factors without the sacrifice of other two. Laboratory scale analyzing or screening chemical additives of wet-end was reported in this study based on RDA sheet molding. Different from the conventional test method, simultaneous consideration of three important wet-end properties could be made by RDA and consequently more reliable prediction of actual paper machine wet-end could be expected.

Puerarol from the Roots of Pueraria lobata Inhibits the Formation of Advanced Glycation End Products (AGEs) in vitro

  • Kim, Jong-Min;Jang, Dae-Sik;Lee, Yun-Mi;Kim, Young-Sook;Kim, Jin-Sook
    • Natural Product Sciences
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    • v.14 no.3
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    • pp.192-195
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    • 2008
  • Three known compounds, puerarol (1), pueroside B (2), and ononin (3), were isolated from an EtOAc-soluble fraction of the roots of Pueraria lobata. The isolates (1 - 3) were subjected to an in vitro bioassay to evaluate their inhibitory activity on the formation of advanced glycation end products (AGEs). Puerarol (1) exhibited a remarkable inhibitory activity on AGEs formation with $IC_{50}$ value of $2.05{\pm}0.32{\mu}M$ as compared with positive control, aminoguanidine ($IC_{50}$ value : $905.32{\pm}7.58{\mu}M$).

The Formation of Rope- and Pebbles-Type Aggregation from the Micro-End-to-End and -Side-by-Side Aggregates in Poly(L-proline) Solutions

  • 김현돈
    • Bulletin of the Korean Chemical Society
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    • v.18 no.9
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    • pp.929-933
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    • 1997
  • Morphological studies in the micro-end-to-end (m-E-E) and micro-side-by-side (m-S-S) aggregations were conducted by using of scanning electron microscope (SEM) for the samples precipitated by heating of the end-products of the transition of FormⅡ (left-handed helix, three peptides per turn, 31) Form Ⅰ (right-handed helix, 3.3 peptides per turn, 103) in poly(L-proline) (PLP) in acetic acid(water)-propanol (1:9 v/v) solvent. The observed morphology for the solide state shows a rope (or super helical) type and pebbles type aggregate for the (m-E-E) and (m-S-S) aggregate respectively. The viscosities were also measured during the heat-precipitation in order to elucidate the process of formation of the rope- and pebbles-type aggregates. The result for the (m-E-E) aggregations exhibit two steps, i.e., at first, the viscosity increases with time (step 1), thereafter it decrease until attain the last value (step 2). But the (m-S-S) aggregations show only one step in the decreases in viscosity. On the bases of all experimental results it is possible to propose a reasonable mechanism for the formation of the two types of aggregates of the (m-E-E) and (m-S-S).

Phenolic Compounds from the Leaves of Homonoia riparia and their Inhibitory Effects on Advanced Glycation End Product Formation

  • Lee, Ik-Soo;Jung, Seung-Hyun;Kim, Chan-Sik;Kim, Jin Sook
    • Natural Product Sciences
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    • v.23 no.4
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    • pp.274-280
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    • 2017
  • In a search for novel treatments for diabetic complications from natural resources, we found that the ethyl acetate-soluble fraction from the 80% ethanol extract of the leaves of Homonoia riparia has a considerable inhibitory effect on advanced glycation end product (AGE) formation. Bioassay-guided isolation of this fraction resulted in identification of 15 phenolic compounds (1 - 15). These compounds were evaluated in vitro for inhibitory activity against the formation of AGE. The majority of tested compounds, excluding ethyl gallate (15), markedly inhibited AGE formation, with $IC_{50}$ values of $2.2-89.9{\mu}M$, compared with that of the positive control, aminoguanidine ($IC_{50}=962.3{\mu}M$). In addition, the effects of active isolates on the dilation of hyaloid-retinal vessels induced by high glucose (HG) in larval zebrafish was investigated; (-)-epigallocatechin-3-O-gallate (6), corilagin (7), and desmanthine-2 (11) significantly decreased HG-induced dilation of hyaloid-retinal vessels compared with the HG-treated control group.

Constituents of the Roots of Pueraria Iobata Inhibit Formation of Advanced Glycation End Products (AGEs)

  • Kim, Jong-Min;Lee, Yun-Mi;Lee, Ga-Young;Jang, Dae-Sik;Bae, Ki-Hwan;Kim, Jin-Sook
    • Archives of Pharmacal Research
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    • v.29 no.10
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    • pp.821-825
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    • 2006
  • Two isoflavone C-glucosides, puerarin (1) and PG-3 (2), a but-2-enolide, $({\pm})-puerol$ B (3), two isoflavone O-glucosides, daidzin (4) and genistin (5), and three pterocarpans, (-)-medicarpin (6), (-)-glycinol (7) and (-)-tuberosin (8), were isolated from a MeOH extract of the roots of Pueraria Iobata, using an in vitro bioassay based on the inhibition of the formation of advanced glycation end products (AGEs) to monitor chromatographic fractionation. The structures of 1-8 were determined by spectroscopic data interpretation, particularly by 1D- and 2D-NMR studies, and by comparison of these data with values in the literature. All of the isolates (1-8) were evaluated for their inhibitory activity on AGEs formation in vitro. Of these, puerarin (1), PG-3 (2), and $({\pm})-puerol$ B (3) exhibited more potent inhibitory activity than the positive control aminoguanidine.

Effect of Milling Medium Materials on Mechanical Alloying of Mo-25.0at%Si Powder Mixture (Mo-25.0at%Si 혼합분말의 기계적 합금화에 미치는 밀링매체 재료의 영향)

  • 박상보
    • Journal of Powder Materials
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    • v.5 no.1
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    • pp.64-70
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    • 1998
  • Milling media of steel and partially stabilized zirconia(PSZ) were used to produce $Mo_3$Si by mechanical alloying(MA) of Mo-25.0at%Si elemental powder mixture. The effect of milling medium materials on MA of the powder mixture have been investigated by XRD and DTA. The reaction rate and the end-product noticeably depended upon the milling medium material. The formation of $Mo_3$Si and $Mo_5Si_3$phases by PSZ ball-milling took place after 15 hr of MA and was characterized by a slow reaction rate as Mo, Si, $Mo_5Si_3$ and $Mo_3$Si coexisted for a long period of milling time. The formation of a new phase by steel ball-milling, however, did not take Place even after 96 hr of MA. DTA and annealing results showed that $Mo_5Si_3$ and $Mo_3$Si were formed after heating the ball-milled powder specimens to different temperatures. At low temperatures, Mo and Si were transformed into $Mo_5Si_3$. At high temperatures, the formation of $Mo_3$Si can be partially attributed to the reaction, 7Mo+Si+$Mo_5Si_3$-.4$Mo_3$Si . The formation of $Mo_3$Si and Mo5Si3 phases by mechanical alloying of the powder mixture and the relevant reaction rate appeared to depend upon the milling medium material as well as the thermodynamic properties of the end-products.

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Application of the Novel Test Machine, Retention Drainage Analyzer(RDA), for Wet-End Analysis of Papermaking Process (I) (제지공정의 WET-END 분석을 위한 새로운 감압 탈수 초지설비(RDA)의 활용(제1보) - RDA를 활용한 종이 균일성 예측 -)

  • 우이균;류정용;김용환;송봉근;조남석
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.4
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    • pp.1-6
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    • 2002
  • In order to simulate the actual wet-end process in papermachine, RDA, a novel handsheet former, was used and following results were obtained. While the addition of polyelectrolytes gives significant effect on fiber flocculation, increase of stock consistency influenced on the formation of RDA sheets greatly. In particular, the consistency increase from 0.3 % to 0.4% abruptly increased floe size of RDA sheet and it results in severe deterioration of paper strength. Stock consistency, therefore, should be regarded as the most important factor in the formation simulation with RDA and should be controlled as the first sequence of tuning the operating conditions of RDA to simulate correctly the target machine paper's formation.

Naphthopyrone Glucosides from the Seeds of Cassia tora with Inhibitory Activity on Advanced Glycation End Products (AGEs) Formation

  • Lee, Ga-Young;Jang, Dae-Sik;Lee, Yun-Mi;Kim, Jong-Min;Kim, Jin-Sook
    • Archives of Pharmacal Research
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    • v.29 no.7
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    • pp.587-590
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    • 2006
  • Three naphthopyrone glucosides, cassiaside (1), $rubrofusarin-6-O-{\beta}-D-gentiobioside$ (2), and $toralactone-9-O-{\beta}-D-gentiobioside$ (3), were isolated from the BuOH-soluble extract of the seeds of Cassia tora as active constituents, using an in vitro bioassay based on the inhibition of advanced glycation end products (AGEs) to monitor chromatographic fractionation. The structures of 1-3 were determined by spectroscopic data interpretation, particularly by extensive 1D and 2D NMR studies. All the isolates (1-3) were evaluated for the inhibitory activity on AGEs formation in vitro.

Screening of Korean Herbal Medicines with Inhibitory Activity on Advanced Glycation End Products Formation (IX) (한국약용식물의 최종당화산물 생성저해활성 검색 (IX))

  • Lee, Yun Mi;Kim, Young Sook;Kim, Joo Hwan;Kim, Jin Sook
    • Korean Journal of Pharmacognosy
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    • v.44 no.3
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    • pp.298-304
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    • 2013
  • In this study, 64 Korean herbal medicines have been investigated with an in vitro evaluation systems using glycation end products (AGEs) formation inhibitory activity. Of these, 30 herbal medicines ($IC_{50}<50{\mu}g/ml$) were found to have significant AGEs formation inhibitory activity. Of these, four herbal medicines ($IC_{50}<5{\mu}g/ml$) were found to have significant AGEs formation inhibitory activity. Particularly, Cornus controversa (branches and leaves), Acer ginnala (stems and leaves), Platycarya strobilacea (flowers) and Picrasma quassioides (stems), showed more potent inhibitory activity (approximately 17-27 fold) than the positive control aminoguanidine ($IC_{50}=77.04{\mu}g/ml$).