• Journal of the KSME
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• v.42 no.7
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• pp.30-34
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• 2002

• Kyungpook Mathematical Journal
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• v.19 no.1
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• pp.39-42
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• 1979

• Digital Contents
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• no.5 s.108
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• pp.42-44
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• 2002

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.587-596
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• 2019

This study aimed to determine the antimalarial effect of the Strychnos ligustrina (SLW) wood extracts and to analyze its phytochemicals. The SLW powder samples were macerated with 100% ethanol (E100), 75% ethanol (E75), 50% ethanol (E50), 25% ethanol (E25), and aqueous (A100). The extracts were analyzed by LCMS/MS, and its in-vitro antimalarial activity was tested with Plasmodium falciparum. The results showed that the extract yields of E100, E75, E50, E25, and A100 were 4.3, 5.2, 5.3, 4.7, and 3.6%, respectively. The antimalarial activities of the A100, E25, E50, and E75 extracts were classified as active with $IC_{50}$ values of 38.6, 42.6, 42.9, and $43.7{\mu}g/mL$, respectively. But, the antimalarial activity of the E100 extract was classified as slightly active with $IC_{50}$ values of $87.4{\mu}g/mL$. The dominant compounds contained in the extracts of A100, E25, E50, E75, and E100 was the alkaloid compound, namely brucine with relative concentrations of 24.96, 24.55, 21.33, 11.79, and 11.62%, respectively.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.67-70
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• 1965

Polarographic studies of reduction of Ni(Ⅱ)-CN complex on Hg-electrode have indicated that $Ni(CN)_4^{2-}$ is reduced by two paths, via one electron process Ni(CN)42- + e [1]↔[2] Ni(CN)43- =(eq) Ni(CN)2- + 2CN- and via two electron process Ni(CN)42- + 2e [3]→ 1/2[Ni(CN)33-]2 + CN- of which reduction [1] must be faster than reduction [3]. At very dilute cyanide concentration (0.004 to 0.01 M) cathodic wave is practically responsible for reaction [1] and two cyanide ions appear to contribute to the reaction. As increasing cyanide ion concentration the rate of oxidation reaction [2] catalysed by Hg increases and reaction [1] and [2] approach to equilibrium. Therefore, reaction [3] represents the cathodic wave at high concentration of cyanide (above 0.2 M). This mechanism can also explain the fact that limiting current at $[CN^-]$ = 8 M is approximately twice of that at 0.004 M CN.

• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.267-274
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• 2012

To understand morphological and genetic differentiation between Euphorbia esula and E. maackii we examined 12 morphological characters and 11 isozyme loci from 14 populations of two species. Species of E. esula complex (A = 1.63, P = 44.83, $H_e$ = 0.198) in Korea maintain nearly as high as the genetic diversity reported in East Asian E. jolkinii and E. fauriei while lower than those of E. ebracteolata and E. pekinensis in Korea. Although the ranges of most morphological character variation of the two species overlap, E. esula and E. maackii were well recognized by the combination of the morphological traits, and the result of UPGMA phenogram supports the two distinct species inhibited in Korea. However, isozyme data do not support the recognition of E. esula and E. maackii. The discordance between morphological and allozyme data should be explained by the recent divergence or gene flow via introgressive hybridization between two species.

• BMB Reports
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• v.42 no.11
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• pp.719-724
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• 2009

Recent studies have revealed that endoplasmic reticulum (ER) disturbance is involved in the pathophysiology of neurodegenerative disorders, contributing to the activation of the ER stress-mediated apoptotic pathway. Therefore, we investigated here the molecular mechanisms underlying the ER-mitochondria axis, focusing on calcium as a potential mediator of cell death signals. Using NT2 cells treated with brefeldin A or tunicamycin, we observed that ER stress induces changes in the mitochondrial function, impairing mitochondrial membrane potential and distressing mitochondrial respiratory chain complex Moreover, stress stimuli at ER level evoked calcium fluxes between ER and mitochondria. Under these conditions, ER stress activated the unfolded protein response by an overexpression of GRP78, and also caspase-4 and-2, both involved upstream of caspase-9. Our findings show that ER and mitochondria interconnection plays a prominent role in the induction of neuronal cell death under particular stress circumstances.

• BMB Reports
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• v.42 no.3
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• pp.172-177
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• 2009

Phosphoglucose isomerase (PGI) is involved in synthesizing extracellular polysaccharide (EPS). The gene encoding PGI in Sphingomonas chungbukensis DJ77 was cloned and expressed in E. coli, and the protein was characterized. The pgi gene from DJ77 is 1,503 nucleotides long with 62% GC content and the deduced amino acid sequence shows strong homology with PGIs from other sources. The molecular masses of PGI subunit and native form were estimated to be 50 kDa and 97 kDa, respectively. Four potentially important residues (H361, R245, E330 and K472) were identified by homology modeling. The mutations, H361A, R245A, E330A, R245K and E330D resulted in decrease in Vmax by hundreds fold, however no significant change in Km was observed. These data suggest that the three residues (H361, R245Aand E330) are likely located in the active site and the size as well as the spatial position of side chains of R245 and E330 are crucial for catalysis.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.3
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• pp.198-208
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• 2016

A well-established e-health strategy at the national level is necessary to successfully achieve the trust-and-consensus-based e-health goals by linking strategic information planning and the execution of an implementation plan. This paper provides a methodology of how to establish a national e-health strategy and the case of e-Health Information Strategic Planning (ISP) of the Ministry of Health and Welfare of Korea. The ISP is to improve the quality of care and contribute to the economic growth by integrating a variety of policies and providing affordable and competitive services.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.52-57
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• 1987

To know the effects of weeding periods (weeding from 12 days, 28 days and 42 days after seeding to harvest, and weeding from seeding to 14 days, 28 days and 42 days after seeding) and growing conditions such as transparent polyethylene film mulch (P.E. mulch) and bare soil on growth and yield of peanuts, "Yeongho-Tangkong" was planted on May 10, 1984. Under P.E. mulch, the number of weeds was higher, but the weed dry weight was lower than in bare soil by the middle of July. Sixty days after seedings, the length of main stems in weedy check plots was longer, but shoot dry weight was lower compared to weed free plot. In the correlation coefficients between weed dry weight and the shoot dry weight of peanut on July 14, the growth retardation of peanuts due to weeds was showed earlier under P.E. mulch than in bare soil. Shoot dry weight, shelling ratio, number of seeds per pod, 100 pod weight, and seed yield were higher under P.E, mulch compared to bare soil. But weed dry weight, length of branches, number of pod bearing branches, number of pods per square meters, and pod yield were similar between P.E. mulch and bare soil. Shoot dry weight of peanuts, length of branches, number of pod bearing branches, number of pods per square meters, pod yield, 100 pod weight, 100 seed weight, and seed yield in weed free plots from 28 days after seeding to harvest (28 DAS-Harvest) were higher compared to weed free plots from 42 DAS-Harvest. However, in the weed free plot from seeding to 42 days after seeding seed yield was lower than that of the continuous weeding plot due to lower number of pod bearing branches and number of pods per square meters. When weed was not controlled at the later growth stages of peanuts, reduction in seed yield due to weeds was greater in bare soil than that under P.E. mulch.