Gwangju Regional Food and Drug Administration

Gwangju, South Korea

Gwangju Regional Food and Drug Administration

Gwangju, South Korea
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Kim N.H.,Korean University of Science and Technology | Kim M.J.,Korean University of Science and Technology | Kang Y.S.,Gwangju Regional Food and Drug Administration | Hwang I.G.,South Korea National institute of Food and Drug Safety Evaluation | Rhee M.S.,Korean University of Science and Technology
Food Quality and Preference | Year: 2015

Little is known about the eating behavior of Asian children when faced with a range of poorly nutritious foods sold around schools, and whether they appreciate the risks involved in consuming such foods. To provide adequate education regarding proper food consumption, it is essential to understand how children perceive the potential risks and to examine their actual eating behaviors. The perceptions of adults and children should also be compared. This study selected children from the most populous primary schools (n= 166) in 36 of the national capital regions of the Republic of Korea. A total of 443 children were randomly selected from each school and they, their parents (n= 425), and nutrition teachers (n= 166) were asked to complete a questionnaire (total 11 questions) designed to examine how children and adults perceived the risks associated with the consumption of cheap and poorly nutritious foods sold around schools. Most children (>70%) consumed these foods more than once per week, even though they were aware that they may be potential hazardous. Children were significantly less concerned about the risks associated with their eating behaviors than their parents and teachers (p<. 0.05), particularly regarding snacks prepared and cooked under unhygienic conditions. Although parents and teachers were very concerned about children's food consumption, they misunderstood the level of children's awareness, their preferences, and their actual eating behaviors. This study generated a database of information about children's actual eating behavior around schools, and the perception (by children, parents, and teachers) of the risks. This database may contribute to the design of suitable educational programs for children, parents, and teachers. © 2015 Elsevier Ltd.


Roh S.-H.,Chosun University | Cheong H.,Chosun University | Park J.,Chosun University | Sohn H.,Chosun University | And 2 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2014

Codehydrocoupling (using Red-Al) followed by borane/phosphine-capping (with Ph2BCl and Ph2PCl) of 1,1-dihydrotetraphenylsilole (1) and 1,1- dihydrotetraphenylgermole (2) (9:1 mole ratio) gave electroluminescent poly(silole-co-germole)s containing borane/phosphine-ends (3, 4) in high yield. The borane-terminated copolymer 3 emits at 522 nm and are electroluminescent at 521 nm. The fluorescence quantum yield of 3 in toluene is (1.60±0.30) ×10-2. The phosphine-terminated copolymer 4 emits at 520 nm and are electroluminescent at 520 nm. The fluorescence quantum yield of 4 in toluene is (1.60±0.20)×10-2. 3 and 4 were then mixed in 1:1 ratio. The emission color of 3/4 mixture is green and the maximum brightness of the device is 2,760 cd/m2 with a luminous efficiency of 0.67 lm/W. The borane/phosphine end groups in the 1:1 mixture of 3 and 4 exhibited no appreciable effect on the luminescent properties in spite of possible B P dative bonding. Ge-132 helped to increase the B P dative bonding. The electroluminescent copolymers 3 and 4 are good candidates for PLED (polymer light-emitting diode) fabrication. Copyright © 2014 American Scientific Publishers.


Cheong H.,Chosun University | Roh S.-H.,Chosun University | Cho M.-S.,Gwangju Regional Food and Drug Administration | Kim M.-H.,University of Wisconsin - Madison | And 5 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2013

Combinative one-pot Si-Si/Si-O dehydrocoupling of hydrosilanes with alcohols (1:1.5 mole ratio), mediated by a mixture of AgNO3-AuCl 3 (100/1 mole ratio) rapidly produced poly(alkoxysilane)s in reasonably high yield. The addition of small amount of gold complex to the reaction mixture effectively accelerated the coupling reaction compared to the reaction rate with AgNO3 alone. The hydrosilanes include p-X-C 6H4SiH3 (X = H, CH3, OCH 3, F), PhCH2SiH3, and (PhSiH2) 2. The alcohols include MeOH, EtOH, iPrOH, PhOH, and CF 3(CF2)2CH2OH. The weight average molecular weight and polydispersity of the poly(alkoxysilane)s were in the range of 1,600∼8,000 Dalton and 1.4∼3.5, respectively. The dehydrocoupling reactions of phenylsilane with ethanol (1:3 mole ratio) in the presence of the Ag-Au complexes gave only triethoxyphenylsilane. Copyright © 2013 American Scientific Publishers All rights reserved.


Kim M.-H.,Chonnam National University | Lee J.,Chonnam National University | Mo S.-Y.,Chonnam National University | Woo H.-G.,Chonnam National University | And 7 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2011

Si-Si/Si-O dehydrocoupling of hydrosilanes with alcohols (1:1.5 mole ratio), catalyzed by AgNO 3 which converted to Ag(0) colloidal nanoparticles, gave poly(alkoxysilane)s in one-pot in moderate to high yield. The hydrosilanes include p-X-C 6H 4SiH 3 (X = H, CH 3, OCH 3, F), PhCH 2SiH 3, and (PhSiH 22. The alcohols include MeOH, EtOH, iPrOH, PhOH, and CF 3(CF 2) 2CH 2OH. The weight average molecular weight and polydispersity of the poly(alkoxysilane)s were in the range of 1,600∼8,000 Dalton and 1.4∼3.5. The dehydrocoupling reactions of phenylsilane with ethanol (1:3 mole ratio) in the presence of the silver nanocolloid catalyst produced only triethoxyphenylsilane as product. Copyright © 2011 American Scientific Publishers All rights reserved.


Kim M.-H.,Chonnam National University | Woo H.-G.,Chonnam National University | Lee B.-G.,Chonnam National University | Cho M.-S.,Gwangju Regional Food and Drug Administration | And 3 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2010

The dry sol-gel co-polycondensation at toluene in ambient air atmosphere of p-X-C 6H 4SiH 3 (X = H, CH 3, CH 3O, F, Cl) and p-H 3Si-C 6H 4SiH 3 (9:1 mole ratio) to co-silicas (p-X-C 6H 4SiO 1.5) 9(p-O 1.5SiC 6H 4SiO 1.5) 1 in high yield, catalyzed by colloidal nickel nanoparticles in-situ generated from nickelocene(II) Is described. The co-gels (p-X-C 6H 4SiO 1.5S) 9(P-O 1.5Si-C 6H 4SiO 1.5), with higher molecular weights and TGA residue yield were obtained when compared to the homogels p-X-C 6H 4SiO 1.5. Some degree of unreacted Si-H bonds still remained in the gel matrix because of steric bulkiness. All the insoluble gels adopt an amorphous structure with a smooth surface. A plausible mechanism for the dry sol-gel reaction was provided Copyright © 2010 American Scientific Publishers All rights reserved.


Park E.-S.,Konkuk University | Kang S.-I.,Chungbuk National University | Yoo K.-D.,Gwangju Regional Food and Drug Administration | Lee M.-Y.,Korea University | And 5 more authors.
Experimental Cell Research | Year: 2013

The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5-2. μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. © 2013 Elsevier Inc.


Lee J.-A.,University of Seoul | Kim M.-K.,University of Seoul | Kim H.-M.,Yonsei University | Lee J.K.,Gwangju Regional Food and Drug Administration | And 4 more authors.
International Journal of Nanomedicine | Year: 2015

Background: Orally administered particles rapidly interact with biological fluids containing proteins, enzymes, electrolytes, and other biomolecules to eventually form particles covered by a corona, and this corona potentially affects particle uptake, fate, absorption, distribution, and elimination in vivo. This study explored relationships between the biological interactions of calcium carbonate particles and their biokinetics. Methods: We examined the effects of food grade calcium carbonates of different particle size (nano [N-Cal] and bulk [B-Cal]: specific surface areas of 15.8 and 0.83 m2/g, respectively) on biological interactions in in vitro simulated physiological fluids, ex vivo biofluids, and in vivo in gastrointestinal fluid. Moreover, absorption and tissue distribution of calcium carbonates were evaluated following a single dose oral administration to rats. Results: N-Cal interacted more with biomatrices than bulk materials in vitro and ex vivo, as evidenced by high fluorescence quenching ratios, but it did not interact more actively with biomatrices in vivo. Analysis of coronas revealed that immunoglobulin, apolipoprotein, thrombin, and fibrinogen, were the major corona proteins, regardless of particle size. A biokinetic study revealed that orally delivered N-Cal was more rapidly absorbed into the blood stream than B-Cal, but no significant differences were observed between the two in terms of absorption efficiencies or tissue distributions. Both calcium carbonates were primarily present as particulate forms in gastrointestinal fluids but enter the circulatory system in dissolved Ca2+, although both types showed partial phase transformation to dicalcium phosphate dihydrate. Relatively low dissolution (about 4%), no remarkable protein–particle interaction, and the major particulate fate of calcium carbonate in vivo gastrointestinal fluids can explain its low oral absorption (about 4%) regardless of particle size. Conclusion: We conclude that calcium carbonate nanoparticles can act more actively with biological matrices in vitro and ex vivo, but that in vivo, their biological interactions and biokinetics are not affected by particle size. © 2015 Lee et al.

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