• Animal cells and systems
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• 제3권4호
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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.

• 펄프종이기술
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• 제42권3호
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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.

• Natural Product Sciences
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• 제14권3호
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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 : $905.32{\pm}7.58{\mu}M$).

• Bulletin of the Korean Chemical Society
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• 제18권9호
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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).

• Natural Product Sciences
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• 제23권4호
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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.

• Archives of Pharmacal Research
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• 제29권10호
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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.

• 한국분말재료학회지
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• 제5권1호
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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.

• 펄프종이기술
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• 제34권4호
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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.

• Archives of Pharmacal Research
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• 제29권7호
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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.

• 생약학회지
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• 제44권3호
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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 ($IC_{50}=77.04{\mu}g/ml$).