• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.762-767
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• 2009

In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.823-831
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• 1995

The composition of rumen volatile fatty acids(VFA) and the blood chemistry were investigated in 5 clinically health dairy cows(Group I) reared on dairy farms and in 5 cows with post-parturition(POP) primary ketosis(Group II). The determinations were performed on days 5 to 7 pre-parturition(PRP), immediately POP, and on days 5, 10, 15, 20 and 25 POP. In both groups, the total VFA levels gradually increased starting from day 5 POP, but the levels were lower in Group II than in Group I. With regard to POP. changes in the composition of VFA, Group II occasionally showed lower levels of acetic acid and caproic acid than did Group I. Blood glucose levels decreased POP in both groups. In contrast, blood levels of ketone bodies and 3-hydroxybutyric acid were increased POP, but there was no statistically by significant difference between the groups. The aspartate aminotransferase level was transiently increased immediately POP in both groups, and the increase was more marked in Group II than in Group I. Both groups showed a tendency for total cholesterol, free cholesterol, ester cholesterol, phospholipid, and total bile acid to be increased POP, but there was no statistically significant difference between the groups. Clinically healthy dairy cows also showed POP changes in the composition of VFA and blood similar to those in dairy cows with ketosis, suggesting that even apparently healthy cows are at risk of subclinical ketosis POP.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.345-355
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• 2010

Background: Extracellular and intracellular pH ($pH_o$ and $pH_i$), which can be changed in various pathological conditions such as hypoxia, affects vascular contractility. To elucidate the mechanism to alter vascular contractility by pH, the effects of pH on reactivity to vasocontracting agents, intracellular $Ca^{2+}$ influx, and $Ca^{2+}$ sensitivity in vascular smooth muscle were examined. Material and Method: Isometric contractions in rat superior mesenteric arteries (SMA) were observed. Intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) was recorded by microfluorometer using Fura-2/acetoxylmethyl ester in muscle cells. $pH_o$ was increased from 7.4 to 7.8 or decreased to 6.9 or 6.4. $pH_i$ was decreased by applying $NH_4^+$ or propionic acid or modulated by changing $pH_o$ after increasing membrane permeability using $\beta$-escin. Result: Decreases in $pH_o$ from 7.4 to 6.9 or 6.4 shifted concentration-response curve by norepinephrine (NE) or serotonin (SE) to the right and significantly increased half maximal effective concentration (EC50) to NE or SE. Increase in $pH_o$ from 7.4 to 7.8 shifted concentration-response curve by norepinephrine (NE) or serotonin (SE) to the left and significantly reduced EC50 to NE or SE. NE increased $[Ca^{2+}]_i$ in cultured smooth muscle cells from SMA and the increased $[Ca^{2+}]_i$ was reduced by decreases in $pH_o$. NE-induced contraction was inhibited by $NH_4^+$, whereas the resting tension was increased by $NH_4^+$ or propionic acid. When the cell membrane of SMA was permeabilized using ${\beta}$-escin, SMA was contracted by increasing extracellular $Ca^{2+}$ concentration from 0 to $10{\mu}M$ and the magnitude of contraction was decreased by a decrease in $pH_o$ and vice versa. Conclusion: From these results, it can be concluded that a decrease in $pH_o$ might inhibit vascular contraction by reducing the reactivity of vascular smooth muscle to vasoactive agents, $Ca^{2+}$ influx and the sensitivity of vascular smooth muscle to $Ca^{2+}$.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.4
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• pp.295-305
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• 2001

Protein kinase C (PKC) is known to play a pivotal role in neoplastic transformation cells and its high expression is often found in a variety of types of tumors including oral cancer. While PKC is associated with the altered signal transduction pathway of the tumor cells, it is still unclear which isoform is involved in the carcinogenesis process. Since the cellular distributions and the roles of PKC are isoform-specific, it is very important to identify the specific target molecules to improve our understanding of the carcinogenesis processes. Thus, the present study attempted to perform chemical carcinogen-induced neoplastic transformation of human epithelial cells and analyze the specific isoform of PKCs involved in the cellular transformation. The study analyzed overall PKC responses upon MNNG(N-Methyl-N'-nitro-N-nitroso guanidine) exposure with [$^3H$] PDBu binding assay. PKC translocation was observed at high doses of MNNG treatment in the presence of extracellular calcium. Such effects were not observed in the absence of extracellular calcium. Translocational effects with exposure of MNNG was further enhanced in the presence of hydrocortisone. The result suggests that the type of PKC involved may be $Ca^{2+}$-dependent classical isoform and steroid hormone enhances PKC activation. Among cPKC isoforms examined, only $PKC-{\alpha}$ and r showed significant translocation of protein levels from cytosolic fraction to membrane fraction, as analyzed by immunoblot. $PKC-{\varepsilon}$ in nPKC class showed an inch·eased translocation, but other forms in this class did not show the effect. None of isoforms in aPKC class was affected by MNNG treatment. The study demonstrated that there was a certain specificity in the patterns of isoform induction follwong chemical carcinogen exposure and helped identify all the types of PKC isoforms expressed in human epithelial cells. It was revealed that PKC isoforms were activated in an early resonse to chemical carcinogen, suggesting that PKC be associated with carcinogenesis process from an early stage in this particular cell system. The study will contribute to improving our understanding of chemical-induced carcinogenesis in human cells and may provide a scientific basis to introduce the specific PKC inhibitors as an anticancer drug of epithelial cell-origin cancers including oral cancer.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.172-183
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• 1999

Background: Nitric oxide is a short-lived effector molecule derived from L-arginine by the nitric oxide synthase(NOS). Nitric oxide plays a role in a number of physiologic and pathophysiologic functions including host defense, edema formation, and regulation of smooth muscle tone. Some kinds of cells including macrophage are known to produce large quantities of nitric oxide in response to inflammatory stimuli such as interleukin-$1\beta$(IL-$1\beta$), tumor necrosis factor-$\alpha$(TNF-$\alpha$), interferon-$\gamma$(IFN-$\gamma$) and lipopolysaccharide(LPS). Reactive oxygen species are also known to be important in the pathogenesis of acute cell and tissue injury such as acute lung injury model Methods: Using the RA W264.7 cells, we have examined the ability of oxidant hydrogen peroxide($H_2O_2$) to stimulate nitric oxide production and inducible NOS mRNA expression. Also, we have examined the effects of NOS inhibitors and antioxidants on $H_2O_2$ induced nitric oxide production. Results: Stimulation of RAW264.7 cells with combinations of 100 ng/ml IL-$1\beta$, 100 ng/ml TNF-$\alpha$, and 100 U/ml IFN-$\gamma$ or 100 U/ml IFN-$\gamma$ and $1{\mu}g/ml$ LPS induced the synthesis of nitric oxide as measured by the oxidation products nitrite($NO_2^-$) and nitrate($NO_3^-$). Addition of $250 {\mu}M-2$ mM $H_2O_2$ to the cytokines significantly augmented the synthesis of $NO_2^-$ and $NO_3^-$(p<0.05). When cells were incubated with increasing concentrations of $H_2O_2$ in the presence of IL-$1\beta$, TNF-$\alpha$ and IFN-$\gamma$ at constant level, the synthesis of $NO_2^-$ and $NO_3^-$ was dose-dependently increased(p<0.05). $N^G$-nitro-L-arginine methyl ester(L-NAME), dose dependently, significantly inhibited the formation of $NO_2^-$ and $NO_3^-$ in cells stimulated with LPS, IFN-$\gamma$ and $H_2O_2$ at constant level(p<0.05). Catalase significantly inhibited the $H_2O_2$-induced augmentation of cytokine-induced $NO_2^-$ and $NO_3^-$ formation(p<0.05). But, boiled catalase did not produce a significant inhibition in comparison with the native enzyme. Another antioxidant 2-mercaptoethanol and orthophenanthroline dose-dependently suppressed $NO_2^-$ and $NO_3^-$ synthesis(p<0.05). Northern blotting demonstrated that H:02 synergistically stimulated the cytokine-induced iNOS mRNA expression in RA W264.7. Conclusion: These results suggest that $H_2O_2$ contributes to inflammatory process by augmenting the iNOS expression and nitric oxide synthesis induced by cytokines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.175-181
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• 2013

This study investigated the ability of extracts from Lentinus edodes (LE) and rice with Lentinus edodes mycelium (LEM) to inhibit diabetes and obesity. Lipid accumulation significantly decreased by 78% and 74% upon treatment with 300 ${\mu}g/mL$ of LE and LEM, respectively (p<0.01). Cholesteryl ester transfer protein (CETP) inhibition activity increased by 94% and 99% upon treatment with 300 ${\mu}g/mL$ of LE and LEM, respectively. In order to investigate the effect of LE and LEM on diabetes, the inhibition of protein tyrosine phosphate 1B (PTP1B) activity from the LE and LEM extracts at various concentrations (1, 3, 10, 30, 100, 300 ${\mu}g/mL$) was assessed. PTP1B activity by treatment with 10, 30, and 100 ${\mu}g/mL$ of LE, was inhibited at a rate of 7, 9, and 7% respectively. Also, PTP1B activity from treatment with increasing concentration of LEM led to a significant concentration-dependent inhibition of PTP1B activity (p<0.01). LE and LEM were orally administered for 28 days after a high fat diet (HFD). LE and LEM significantly reduced triglyceride, cholesterol, HDL-cholesterol and LDL-cholesterol levels. GOT and GPT were not significantly effected. These results indicate that extracts of LE and rice with LEM have potent activities useful in the treatment of obesity and diabetes mellitus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.986-992
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• 1996

This study was designed to observe the effects of the feeding Platycodon grandiflorum(6 or 22 years) extract on the improvement of the blood glucose, lipids in the serum and liver of alloxaninduced hyperglycemic rats(S.D. strain, ♂), alloxan monohydrate 15mg/kg B.W./day I.P. injection) for 3 weeks. Concentrations of blood glucose were significantly higher in the alloxan administration(I.P.) groups(groups 2, 3 and 4) than those in the control group(group 1, basal diet). Blood glucose concentrations were remarkably lower in the group 3(basa1+alloxan+6years Platycodon grandiflorum) and 4(basa1+alloxan+22years Platycodon grandiflorum) than those in the group 2(basal+alloxan), and particularly, lower in the group 4. Concentrations of total cholesterol and LDL-cholesterol in serum were significantly lower in the groups 3, 4 than those in the group 2, and remarkably, lower in the group 4 than those in the group 3. Concentrations of HDL-cholesterol in serum were tile highest in the group 1. Those in the groups 3 and 4 were higher than those in the group 2. Atherosclerotic index were lower in the group 3, 4 than those in the group 2. In the alloxan-induced diabetic groups(groups 2, 3, 4), the serum free cholesterol, cholesterol ester, triglyceride and phospholipid concentrations were significantly lower in the group 3, 4 than those in the group 2. Contents of total cholesterol, triglyceride and phospholipid in liver were remarkably lower in the all experimental groups than those in the group 2. The activities of aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase In serum were the highest in the group 2, but the other groups were rather lower. From the above research, the Platycodon grandiflorum(6 or 22 years) extracts were effective on the improvement of the blood glucose, lipid compositions in serum and liver. And particularly, Platycodon grandiflorum(22 years) was more effective than those in the Platycodon grandiflorum(6 years).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1029-1035
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• 2013

The objective of this study was to examine the ability of extracts from Phellinus linteus (PL) and rice with Phellinus linteus mycelium (PLM) to inhibit obesity and diabetes. The efficacy of PL and PLM were evaluated using Oil Red O staining, cholesteryl ester transfer protein (CETP) levels, protein tyrosine phosphate 1B (PTP1B) levels, organ weight, and serum lipid levels. Lipid accumulation significantly decreased by 76% and 59% upon treatment with $300{\mu}g/mL$ of PL and PLM, respectively (P<0.01). The inhibition of CETP activity increased 99% upon treatment with $300{\mu}g/mL$ of PL or PLM. Treatment with 3, 10, 30, 100, and $300{\mu}g/mL$ of PL, changed PTP1B activity by 10, 11, 14, 12, and 18% respectively. Also, treatment with increasing concentrations of PLM led to a significant concentration-dependent inhibition of PTP1B activity (P<0.01). PL and PLM were orally administered for 28 days after a high fat diet (HFD). PL significantly (P<0.05) reduced triglyceride and cholesterol levels. In addition, PLM significantly (P<0.05) reduced triglyceride, cholesterol, and HDL-cholesterol levels. GOT and GPT were not significantly affected. These results indicate that PL and PLM extracts have potent and useful activities for the treatment of obesity and diabetes mellitus.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.116-126
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• 2013

Glycol ethers are a group of solvents based on alkyl ethers of ethylene glycol commonly used in paints. These solvents typically have a higher boiling point, together with the favorable solvent properties of lower-molecular weight ethers and alcohols. The word "Glycol ethers" was registered as a United States trademark by Union Carbide Corp. Typically, glycol ethers are found in pharmaceuticals, sunscreens, cosmetics, inks, dyes and water based paints. On the other hand, glycol ethers are used in degreasers, cleaners, aerosol paints and adhesives. Most glycol ethers are relatively water soluble, biodegradable and only a few are considered toxic. Therefore, they are unlikely to pose an adverse risk to the environment. Recent study suggests that occupational exposure to glycol ethers is related to low motile sperm count in men, but the finding has been disputed by others. In this study, skin permeation of 3 types glycol ethers were studied in vitro using matrix such as solvent and detergent. The absorption of glycol ethers[methyl glycol ethers(MC), ethyl glycol ethers(EC) and butyl glycol ethers(BC)] has been measured in vitro through rat skin. Epidermal membranes were set up in Franz diffusion cells and their permeability to PBS measured to establish the integrity of the skin before the glycol ethers were applied to the epidermal surface. Absorption rates for each glycol ethers were determined and permeability assessment made to quantify any irreversible alterations in barrier function due to contact with the esters. Types of glycol ethers in vitro experimental results on MC> EC> BC quickly appeared in the following order: skin permeation was beneficial to the skin permeation small molecular weight, the difference in chemical structure, such as hydrophilic, because with the partition coefficient and solubility mechanisms and passive diffusion to increase the speed at which transmission is considered.

• Journal of the Mineralogical Society of Korea
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• v.31 no.1
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• pp.1-12
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• 2018

A gravity core (RS14-C2) was collected at site RS14-C2 in the continental slope to the east of Pennell-Isellin Bank of the Ross Sea (Antarctica) during PNRA XXIX (Rosslope II Project) Expedition. In order to trace the sediment source, magnetic susceptibility (MS), sand fraction, and clay mineral compositions were analyzed, and AMS $^{14}C$ ages were dated. Core sediments consist mostly of hemipelagic sandy clay or silty clay including ice-rafted debris (IRD). AMS $^{14}C$ age of core-top indicates the modern and Holocene sediments. Based on AMS $^{14}C$ dating, sediment color, MS and sand fraction, core sediments are divided into interglacial and glacial intervals. The interglacial brown sediments are characterized by low MS and sand fraction, whereas the glacial gray sediments are characterized by high MS and sand fraction. Among clay mineral compositions of core sediments, illite is highest (61.8~76.7%), and chlorite (15.7~21.3%), kaolinite (3.6~15.4%), and smectite (0.9~5.1%) are in decreasing order, and these compositions are also divided into the interglacial and glacial/deglacial intervals. During the glacial period, the high content of illite and chlorite indicate sediment supply from the bedrocks of Transantarctic Mountains under the Ross Ice Sheet. In contrast, because of decreasing supply of illite and chlorite by the glacial retreat, smectite and kaolinite contents increased relatively during the interglacial period. During the interglacial period, smectite may be transported additionally by the northeastward flowing surface current from the coast of Victoria Land in the western Ross Sea. Kaolinite may be also supplied to the continental slope by the Antarctic Slope Current from the kaolin-rich metasedimentary rock outcropped on the Edward VII Peninsula.