• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.10a
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• pp.49-57
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• 1995

Protein kinase C (PK-C) represents a central element transducing signals generated by a broad range of pathways which produce the lipid second messenger sn-1,2-diacylglycerol (DAG) directly or indirectly. Many dominant oncogenes have proven to function, at least in part, through this pathway Likewise, this pathway is involved in expression of other aspects of the transformed phenotype, such as tumor invasion or multidrug resistance. As expected from its broad role in cell signaling, PK-C Is also important in a range of other physiological and pathophysiological processes, including inflammation, differentiation, and nerve function.

• International Journal of Quality Innovation
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• v.2 no.1
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• pp.87-105
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• 2001

More than a decade after their development and first wave of deployment, Six Sigma and Lean Manufacturing have recently returned on the corporate agendas of a larger number of corporations across industries and supply chains. In the wake of their re-surge, this commentary addresses the evolution, context, content and deployment patterns of the two distinct management concepts. It also analyses claims in the business press that a merger is taking place between Six Sigma and Lean Manufacturing. Here, it is found that there is not enough evidence to broadly support such claims, and it is only concluded that there is some evidence of an early tend towards a merger and that a possible merger would have many synergies and advantages. Finally, an example from a Scandinavian manufacturing company is provided that explains how Six Sigma and Lean Manufacturing can be used in a beneficial way for companies to reach world-class performance.

• Bulletin of the Korean Chemical Society
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• v.16 no.12
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• pp.1203-1208
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• 1995

Theoretical studies of the effect of the nonleaving group (RY) on the breakdown mechanism of the tetrahedral anionic intermediate, T-, formed by the addition of a less basic phenoxide nucleophile (X) to phenyl benzoates with a more basic phenoxide leaving group (Z) have been carried out using the PM3 MO method. The identity acyl transfer reactions (X=Z) are facilitated by an electron-withdrawing RY whereas they are inhibited by an electron-donating RY group. The results of non-identity acyl transfer reactions indicate that a more electron-donating RY group leads to a greater lowering of the higher barrier, TS2, with a greater degree of bond cleavage, and a greater negative charge development on the phenoxide oxygen atom, whereas the opposite is true for a more electron-withdrawing RY group, i.e., leads to a greater lowering of the lower barrier, TS1. The results provide theoretical basis for the signs of ρXY(>0) and ρYZ(<0) observations.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.1
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• pp.45-50
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• 2013

In this study, lumped-vortex element method and thin airfoil theory were used to analyze aerodynamic characteristics of airfoils with relative motion that had camber lines of NACA $44{\times}{\times}$ airfoil in 2-dimensional unsteady incompressible potential flow. Velocity disturbance due to airfoil was calculated by lumped-vortex element model and force distribution on airfoil by unsteady Bernoulli's equation. Variables in relative motion were considered the period p, the amplitude of flapping $A_f$ and pitching $A_p$, and the phase difference between flapping and pitching ${\phi}_p$ and the angle of attack ${\alpha}$. Due to movement of an airfoil, dag was induced in 2-dimensional unsteady incompressible potential flow. The numerical results show that the aerodynamic characteristics of the airfoil with flapping and pitching at the same time are illustrated. Especially the mean lift coefficient became smaller, but drag coefficient became larger.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.187-196
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• 2008

Two naturalized species, Carduus natans L. and Lepidium latifolium L. were newly reported from Korea. Carduus natans, "Sa-hyang-ung-gung-kwi", was found from Nanjido, Seoul, and Yangsuri and Naejangri, Gyunggi-do. It is distinguished from widely naturalized C. crispus by having large nodding heads (30-60mm in diameter) and acuminate lanceolate involucral bracts. Lepidium latifolium, "Keun-ki-da-dag-naeng-i", was found from Noeul Park, Nanjido, Seoul. It is distinguished from the related species by having tall height (about 1 m), subsessile upper leaves, pinnately lobed lower leaves, and corymbose inflorescence.

• Journal of Nutrition and Health
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• v.35 no.5
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• pp.505-511
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• 2002

The study was designed to compare the anti-carcinogenic effect of different level of conjugated linoleic acid (CLA) in 1,2-dimethylhydrazine (DMH)-treated rats by determining biomarkers (apoptosis, cell proliferation, eicosanoids, 1,2-diacylglycerol) and phospholipid fatty acid profile in colonic mucosa. Eighty male Sprague Dawley rats weighing 180-220g were randomly divided into 4 groups depending on the content of CLA, i.e. 0.0% CLA, 0.5% CLA, 1.0% CLA, 1.5% CLA. The experimental diet contained protein 21.6%, carbohydrate 54.6%, and fat 14.5% including CLA mixture at different level by weight. The experimental diet was fed for 14 weeks with the initiation of intramuscular injection of DMH, which was injected twice a week for 6 weeks to give total amount of 180 mg/kg body weight. Regardless of the amount of CLA supplemented to diet, CLA significantly increased the apoptotic index but did not have significant effect on cell proliferation in colonic mucosa. CLA was undetected in colonic mucosal phospholipid of rats fed the 0% CLA diet and increased to 5.9mg/g phospholipid in rats fed the 0.5% diet. The apoptotic index was increased by 251% and the 1,2-DAG content was decreased by 57% in rats fed 0.5% CLA. No further changes in these variables were observed when CLA in the diet was raised to 1.0% or 1.5%. However, dietary CLA decreased mucosal levels of prostaglandin (PG)E$_2$, thromboxane (TX)B$_2$, and arachidonic acid in dose-dependent manner. The present data indicate that dietary CLA can inhibit DMH-induced colon carcinogenesis by mechanism probably involving increased apoptosis.

• The Plant Pathology Journal
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• v.27 no.1
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• pp.33-36
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• 2011

The genome of a potyvirus isolate associated with chlorotic spots and vein banding symptoms on Spathiphyllum spp., in Andhra Pradesh state, India was amplified by RT-PCR using degenerate potyvirus primers, amplicons cloned, and sequence (1.6 kb) analyzed. This virus isolate shared maximum identity of 74.8% and 80.2% at coat protein (CP) gene nucleotide (906 nucleotides) and amino acid (302 amino acids) levels, respectively with Dasheen mosaic virus (DsMV)-M13 isolate reported from China. But its 3'-UTR (258 nucleotides) had maximum identity of 62.5% with DsMV-Vietnam isolate. The deduced molecular weight of CP is 33.57 kDa and it contained DAG triplet in its N-terminal region. In CP amino acid based phylogenetic analysis, this virus isolate represented a separate branch but closer to DsMV isolates cluster. Based on the molecular criteria set for the discrimination of species and genus in the Potyviridae family, the present virus isolate was identified as a distinct virus species in the genus Potyvirus and proposed the name Spathiphyllum chlorotic vein banding virus (SCVbV).

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.93-101
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• 2014

Asymmetric 1,2-distearoyl-3-oleoyl-rac-glycerol (SSO) triacylglycerol (TAG) is used as a cocoa butter replacer (CBR). In this study, it was produced by lipase-catalyzed interesterification of fully hydrogenated soybean oil (FHSBO) and oleic ethyl ester (OEE) in a batch type reactor at $75^{\circ}C$, 250 rpm. Different molar ratios (FHSBO : OEE=1:1, 1:2 and 1:3, w/w) and various reaction times (1, 2, 3, 4, and 5 hr) were also tested. The optimized condition for SSO was a FHSBO : OEE molar ratio of =1:1 at reaction times of 2, 3, 4, and 5 hr. Enzymatic synthesis generated SSO/SOS, as well as the other TAGs (e.g., PSO/POS, SOO/OSO, SSS), ethyl esters, monoacylglycerol (MAG), and diacylglycerol (DAG). After scale-up, fractionation by solvent (methanol and acetone) fractionation and column chromatography was applied. To reduce ethyl esters, high-melting TAGs (e.g., SSS), and SOO/OSO in reactants, solvent fractionation was applied. Using a silica gel column (sample : silica gel=2:1, wt%), MAG and DAG were removed at $25^{\circ}C$. The major fatty acid composition of the final products (with a high SSO/SOS content) was palmitic acid (C16:0, 10.9~12.9 area%), stearic acid (C18:0, 52.2~54.9 area%), and oleic acid (C18:1, 34.2~35.5 area%). In reversed-phase HPLC analysis, the major TAG species of the final product (FHSBO : OEE=1:1, 2 hr) were SSO/SOS (82.31 area%) and PSO/POS (14.51 area%). Based on the $[SS]^+$ : $[SO]^+$ ratio obtained by RP-HPLC/APCI-MS, the final product had a higher SSO (AAB type TAG) content than cocoa butter (CB). The solid fat index (SFI) of CB and the final product obtained were similar with a narrow melting point range around ~32 to $35^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1563-1575
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• 2023

Acyl-coenzyme A (CoA):diacylglycerol acyltransferase 2 (DGAT2) catalyzes the last stage of triacylglycerol (TAG) synthesis, a process that forms ester bonds with diacylglycerols (DAG) and fatty acyl-CoA substrates. The enzymatic role of Dgat2 has been studied in various biological species. Still, the full description of how Dgat2 channels fatty acids in skeletal myocytes and the consequence thereof in glucose uptake have yet to be well established. Therefore, this study explored the mediating role of Dgat2 in glucose uptake and fatty acid partitioning under short interfering ribonucleic acid (siRNA)-mediated Dgat2 knockdown conditions. Cells transfected with Dgat2 siRNA downregulated glucose transporter type 4 (Glut4) messenger RNA (mRNA) expression and decreased the cellular uptake of [1-¹⁴C]-labeled 2-deoxyglucose up to 24.3% (p < 0.05). Suppression of Dgat2 deteriorated insulin-induced Akt phosphorylation. Dgat2 siRNA reduced [1-¹⁴C]-labeled oleic acid incorporation into TAG, but increased the level of [1-¹⁴C]-labeled free fatty acids at 3 h after initial fatty acid loading. In an experiment of chasing radioisotope-labeled fatty acids, Dgat2 suppression augmented the level of cellular free fatty acids. It decreased the level of re-esterification of free fatty acids to TAG by 67.6% during the chase period, and the remaining pulses of phospholipids and cholesteryl esters were decreased by 34.5% and 61%, respectively. Incorporating labeled fatty acids into beta-oxidation products increased in Dgat2 siRNA transfected cells without gene expression involving fatty acid oxidation. These results indicate that Dgat2 has regulatory function in glucose uptake, possibly through the reaction of TAG with endogenously released or recycled fatty acids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1200-1205
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• 2003

Structured lipids (SL) were synthesized by transesterification of corn oil and conjugated linoleic acid (CLA) in the continuous type reactor using sn-1,3 specific Rhizomucor miehei lipase. The parameters of reaction were observed in terms of flow rate, temperature, and substrate molar ratios. The highest incorporation of CLA was obtained with 1 mL/min flow rate, 55$^{\circ}C$ and 1 : 3 (corn oil/CLA) molar ratio, showing 10.26 ㏖%. When different reaction temperatures and substrate ratios were studied, the highest incorporation was obtained at $65^{\circ}C$ (17.33 ㏖%) and 1 : 5 (corn oil/CLA) ratio (17.50 ㏖%), respectively. After pancreatic lipase analysis, most of all CLA were found at sn-1,3 position. The iodine values of obtained SLs ranged from 110 to 120. From the neutral lipid analysis by normal-phase HPLC, produced SLs composed of 99.35 ∼ 99.89% triacylglycerols, 0.11 ∼ 0.51% 1,2- and 1,3-diacylglycerols, and 0.06 ∼ 0.22% monoacylglycerols.