• Polymer(Korea)
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• v.31 no.1
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• pp.68-73
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• 2007

This study is on the synthesis of reactive polymer modifiers by emulsion polymerization to improve properties of asphalt for paving. Styrene, methyl methacrylate (MMA), isoprene and glycidyl methacrylate (GMA) which has epoxy ring to react with carboxyl group of asphaltene were used to synthesize polymer modifiers. Modifiers with various composition were tested miscibility with asphalt. Modifiers which showed good miscibility with asphalt were investigated by DSC for $T_g$. Existence of epoxy rings and their reaction with asphaltene wore investigated by FTIR. Molecular structures of synthesized modifiers were confirmed by $^1H-NMR$. The synthesized modifiers which showed good miscibility had their $Tg's$ in the range of $37.5{\sim}56.5^{\circ}C$ and had isoprene contents of 30 wt%. They showed good miscibility in the 1 and 2 wt% concentrations, but not in the 3 wt% concentration.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.2
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• pp.58-66
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• 1991

This paper measured the characteristic of the thermal expansion, dielectric and conductivity to use $Sb_2O_3$ Filler in epoxy resin.The results are summarized as follow : 1 ) In the [$155^{\circ}C$] 1, The coefficient of thermal expansion increasing temperature obtained 8.19 in the case of pure epoxy resin and $4.5{\times}10^{-5}$ in the case of the mixing 7[%].2) The peak point of $\varepsilon\iota, \varepsilon\rho$ increasing $Sb_2O_3$ mixing ratio moved on the part of the high temperature. 3) The conductivity value increasing temperature shows the corner on the part of the Tg and it's Value became low the sample material with mixing I[%] than in case of pure epoxy resin.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.2
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• pp.134-140
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• 2018

Chylomicron retention disease, also known as Anderson's disease, is a rare hereditary hypocholesterolemic disorder, recessive inherited, characterized by nonspecific symptoms as abdominal distension, steatorrhea, and vomiting associated with failure to thrive. We describe a patient with failure to thrive, chronic diarrhea and steatorrhea who the diagnosis of chylomicron retention disease was established after several months of disease progression. The genetic study confirmed a homozygosity mutation in SAR1B gene, identifying a mutation never previous described [c.83_84delTG(p.Leu28Argfs*7)]. With this case report the authors aim to highlight for this very rare cause of failure to thrive and for the importance of an attempting diagnosis, in order to start adequate management with low fat diet supplemented with fat-soluble vitamins, reverting the state of malnutrition and avoiding possible irreversible and desvantating complications.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.98-106
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• 2018

In this study, graphene oxide(GO) was synthesized by using Hummer's method. Then, GO was used as a additive for epoxy resin nanocomposites that were prepared by mixing Tetraglycidyl diamino diphenyl methane(TGDDM) and hardner(MDEA+M-MIPA). Thermal and mechanical properties of epoxy resin nanocomposites were confirmed by analytical methods such as TG-DTA, DMA, fracture toughness, tensile strength, and flexural strength. The fracture surfaces of epoxy resin nanocomposites with different content of the GO were observed by a Scanning Electron Microscope(SEM). The mechanism for mechanical properties of epoxy resin nanocomposites was analyzed by modeling of nanocomposites with different GO weight. Due to the GO, both the heat resistance and the glass transition temperature of the epoxy resin nanocomposites were improved. Interestingly, when 0.1wt.% of GO was added to the epoxy resin/hardner mixture, the properties of mechanical increased compared with the neat epoxy resin. This results were caused by an aggregation between the GO.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.279-286
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• 2017

The root bark extract of Aralia taibaiensis is used traditionally for the treatment of diabetes mellitus in China. The total saponin extracted from Aralia Taibaiensis (sAT) has effective combined antihyperglycemic and hypolipidemic activities in experimental type 2 diabetic rats. However, the active compounds have not yet been fully investigated. In the present study, we examined effects of twelve triterpenoid saponins on AMP-activated protein kinase (AMPK) activation, and found that compound 28-O-${\beta}$-D-glucopyranosyl ester (AT12) significantly increased phosphorylation of AMPK and Acetyl-CoA carboxylase (ACC). AT12 effectively decreased blood glucose, triglyceride (TG), free fatty acid (FFA) and low density lipoprotein-cholesterol (LDL-C) levels in the rat model of type 2 diabetes mellitus (T2DM). The mechanism by which AT12 activated AMPK was subsequently investigated. Intracellular ATP level and oxygen consumption were significantly reduced by AT12 treatment. The findings suggested AT12 was a novel AMPK activator, and could be useful for the treatment of metabolic diseases.

• Journal of Nutrition and Health
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• v.40 no.5
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• pp.403-412
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• 2007

This study was designed to examine the effects of Salicornia herbacea L. (glasswort: GW) on the lipid peroxidation and mineral levels in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats weighing 200-220 g by an injection of streptozotocin (STZ) dissolved in a citrate buffer into the tail vein at a dose of 45 mg/kg of body weight. Sprague-Dawley rats were fed an AIN-93 recommended diet and the experimental groups were fed a modified diet containing 10% and 20% of glasswort powder for 4 weeks. The experimental groups were divided into 6 groups which consisted of normal (N)-control group, N-GW 10% and N-GW 20% treated groups, STZ-control, STZ-GW 10% and STZ-GW 20% treated groups. The rats' liver and muscle glycogen, liver and kidney protein, cholesterol and triglyceride (TG) in liver, malondialdehyde (MDA) in liver and kidney values were measured, along with the hepatic of chromium (Cr), iron (Fe), and zinc (Zn) content. The liver glycogen levels was significantly affected in N-GW 20% group among all the experimental groups. The liver MDA levels of the STZ-GW 10% and STZ-GW 20% groups were significantly lower than for the STZ-control group. There were significant differences between the N-control group and the STZ-control group in the hepatic of Zn levels. The hepatic of Cr levels in the N-GW 20% and STZ-GW 10% and STZ-GW 20% groups were significanly higher than for the each control groups. These results exhibited dose related effect of glasswort and it may have favorable influence on lipid peroxidation in the liver.

• Journal of the Korean Applied Science and Technology
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• v.15 no.4
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• pp.35-44
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• 1998

All the triacylglycerols including the molecular species having ${\Delta}^5$-unsaturated fatty acids from the seeds of Pinus Koraiensis, were split into a mixture of diacylglycerols by a Grignard reagent prepared with allyl bromide without arousing acyl chains of a glycerol moiety to migration, and were also easily partially hydrolyzed to diacylglycerols by pancreatic lipase. (S)-(+)-(1-naphthyl)ethyl urethane(NEU) derivatives of the diacylglycerol mixture derived from the triacylglycerols were fractionated into sn-1, 3-, sn-1, 2- and sn-2, 3-DG-NEU by silica-HPLC and the fatty acid composition of these fractions was analysed. $C_{18:1{\omega}9}$ is distributed evenly in the three positions of TG with $C_{18:2{\omega}6}$ mainly located in sn-2 position, while ${\Delta}^5$-unsaturated fatty acids such as ${\Delta}^{5.9}-C_{18:2}$, ${\Delta}^{5.9.12}-C_{18:3}$ and ${\Delta}^{5.11.14}-C_{20:3}$ are exclusively present in the sn-3 position. These results could be confirmed by $^{13}C$-NMR spectroscopy : the signals at $^{\delta}$173.231 ppm and $^{\delta}$172.811 ppm of the carbonyl carbon of acyl moieties indicate the presence of saturated acids and/or $C_{18:1{\omega}9}$ (oleic acid) in the ${\alpha}({\alpha}')$- or ${\beta}$- positions, and $C_{18:2{\omega}6}$ including $C_{18:1{\omega}9}$ in the ${\beta}$-position, respectively. In addition, the resonance at $^{\delta}$173.044 ppm suggested a location of ${\Delta}^5$-unsaturated fatty acid moiety in the ${\alpha}({\alpha}')$-position.

• Nutritional Sciences
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• v.6 no.2
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• pp.85-93
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• 2003

The purpose of this study was to investigate the effects of a butanol fraction of fraction of Alisma canaliculatum All. Braun et Bouche (Ac), and of selenium (Se), on plasma gllucose and lipid levee in streptozotocin (STD-induced diabetic rats. Male Sprague-Dawley rats, fed the AIN-93 recommended diet, were divided into five groups: a non-diabetic control group (no STZ treatment), and four 572-induced diabetic groups which consisted of a diabetic-control group, an Ac-treated group, an Ac-Se treated group, and a Se-treated group. Diabetes was induced in the rats by an injection of STZ into the tail vein at a dose of 45 mg/kg body weight. The butanol (BuOH) fraction of Ac was orally administered at a rate of 400 mg/kg body weight for 21 days to both the Ac and Ac-Se groups. The supplementation of selenium in the Se and Ac-Se groups was achieved by adding (freshly, every day) 2 mg of Se as Na$_2$SeO$_3$ per kg of feed. The rats'body weights and hematocrit (Hct) levels were measured, along with plasma levels of glucose, insulin, cholesterol, HDL-cholesterol, triglyceride (TG), and free fatty acids (FFA). Aminotransferase activities were also analyzed. The non-diabetic rats gained weight, while the diabetic rats lost weight - except in the Ac-Se group, which maintained their initial weight. The blood glucose levels of the Ac group and the Se group were significantly lower than for the diabetic-control group. The plasma triglyceride levels were lowered when both Ac and Se were administered to diabetic rats. The concentrations of plasma FFA in the Ac-Se group were significantly lower compared with the diabetic-control group. Plasma cholesterol levels and alanine aminotransferase activity in the Ac, Ac-Se, and Se groups were significantly lower when compared with the diabetic-control group. Aspartate aminotransferase activity was significantly lower in the Se group compared to the other diabetic groups. These data show that treatment with a butanol fraction of Ac in combination with Se has no synergistic effect. Plasma glucose levels tended to be low when Se was administered to diabetic rats. Supplementation of Se in diabetic rats did not elicit a significant increase in plasma insulin levels or result in hypolipemic effects.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.441-447
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• 2009

This paper presents a detailed experimental study on the sulfate resistance of specimens made with portland cement exposed to sulfate attack. The mortar specimens were immersed in a 5% sodium sulfate solution for 360 days and regularly monitored for visual damage, compressive strength loss and expansion. In addition, at the end of 360 days, the products of sulfate attack and the mechanism of attack were investigated through X-ray diffraction, TG&DSC and scanning electron microscopy. The test results indicated that the sulfate deterioration data was ordinary portland cement > sulfate resistance portland cement > low heat portland cement. The microstructural studies indicated that the main reaction product of deterioration of the mortar specimens was the formation of ettringite, gypsum and thaumasite due to sulfate attack. For portland cement matrices, a low heat cement matrix containing the lowest C3A and silicate ratio (C/S) was beneficient against the sulfate attack.

• Molecules and Cells
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• v.27 no.3
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• pp.291-297
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• 2009

Apolipoprotein (apo) C-III is a marker protein of triacylglycerol (TG)-rich lipoproteins and high-density lipoproteins (HDL), and has been proposed as a risk factor of coronary heart disease. To compare the physiologic role of reconstituted HDL (rHDL) with or without apoC-III, we synthesized rHDL with molar ratios of apoA-I:apoC-III of 1:0, 1:0.5, 1:1, and 1:2. Increasing the apoC-III content in rHDL produced smaller rHDL particles with a lower number of apoA-I molecules. Furthermore, increasing the molar ratio of apoC-III in rHDL enhanced the surfactant-like properties and the ability to lyse dimyristoyl phosphatidylcholine. Furthermore, rHDL containing apoC-III was found to be more resistant to particle rearrangement in the presence of low-density lipoprotein (LDL) than rHDL that contained apoA-I alone. In addition, the lecithin:cholesterol acyltransferase (LCAT) activation ability was reduced as the apoC-III content of the rHDL increased; however, the CE transfer ability was not decreased by the increase of apoC-III. Finally, rHDL containing apoC-III aggravated the production of MDA in cell culture media, which led to increased cellular uptake of LDL. Thus, the addition of apoC-III to rHDL induced changes in the structural and functional properties of the rHDL, especially in particle size and rearrangement and LCAT activation. These alterations may lead to beneficial functions of HDL, which is involved in anti-atherogenic properties in the circulation.