• Korean Chemical Engineering Research
• /
• v.53 no.3
• /
• pp.276-281
• /
• 2015

Nanostructured $TiO_2-SiO_2$ materials have widely been used as anti-reflecting coating, optical-chemical sensors and catalysts because of their superior optical and thermal properties as well as chemical durability. Web type $SiO_2$ microfibers with nano-crystalline $TiO_2$ were prepared by electrospinning of Ti-PCS mixed solution and oxidation controlled heat-treatment, rather simple than sol-gel process. Nano-crystalline anatase phase were formed for the heat-treatment up to $1200^{\circ}C$ and they were finely dispersed in the amorphous $SiO_2$ matrix.

• BMB Reports
• /
• v.37 no.2
• /
• pp.239-245
• /
• 2004

We have previously demonstrated that the redox reactant pyruvate prevents apoptosis in the oxidant model of bovine pulmonary artery endothelial cells (BPAEC), and that the anti-apoptotic mechanism of pyruvate is mediated in part via the mitochondrial matrix compartment. However, cytosolic mechanisms for the cytoprotective feature of pyruvate remain to be elucidated. This study investigated the pyruvate protection against endothelial cytotoxicity when the glycolysis inhibitor 2-deoxy-D-glucose (2DG) was applied to BPAEC. Millimolar 2DG blocked the cellular glucose uptake in a concentration- and time-dependent manner with >85% inhibition at $\geq$5 mM within 24 h. The addition of 2DG evoked BPAEC cytotoxicity with a substantial increase in lipid peroxidation and a marked decrease in intracellular total glutathione. Exogenous pyruvate partially prevented the 2DG-induced cell damage with increasing viability of BPAEC by 25-30%, and the total glutathione was also modestly increased. In contrast, 10 mM L-lactate, as a cytosolic reductant, had no effect on the cytotoxicity and lipid peroxidation that are evoked by 2DG. These results suggest that 2DG toxicity may be a consequence of the diminished potential of glutathione antioxidant, which was partially restored by exogenous pyruvate but not L-lactate. Therefore, pyruvate qualifies as a cytoprotective agent for strategies that attenuate the metabolic dysfunction of the endothelium, and cellular glucose oxidation is required for the functioning of the cytosolic glutathione/NADPH redox system.

• The Korean Journal of Community Living Science
• /
• v.20 no.4
• /
• pp.549-558
• /
• 2009

This study examined the basic information on the native pear c.v. 'Baekwoon' grown in Mt. Baekwoonsan, Gwangyang, to develop as a local specialty product. the sensory characteristics, chemical compositions, and physiological activities of 'Baekwoon' pear were examined and compared with those of 'Niitaka' pear. Hardness of 'Baekwoon' pear was 19.30N, which was higher than 'Niitaka'. The sugar content of 'Baekwoon' was 11.5 $^{\circ}Brix$, which was lower than 'Niitaka'. The total amino acid contents of the fruit skin and flesh of 'Baekwoon' were 222 mg/100g dry weight (DW) and 130 mg/100g DW, respectively, which were much higher than those of 'Niitaka'. Especially, serine contents in fruit skin and flesh of 'Baekwoon' were 75.4 mg/100g DW and 40.2 mg/100g DW, respectively, which were significantly (p<0.05) higher than those of 'Niitaka'. However, physiological activities, such as total phenol content, DPPH radical scavenging activity, total flavonoid content and nitrite scavenging activity, of 'Baekwoon' were lower than or similar to those of 'Niitaka'. Consequently, vitamin and amino acid contents of 'Baekwoon' were better than those of 'Niitaka'. It is suggested to use fruit skin because of its good composition and physiological activities so that it helps to improve the quality and the biological activity.

• Proceedings of the SCSK Conference
• /
• 2003.09b
• /
• pp.12-25
• /
• 2003

L-camitine ($\beta$ -hydroxy-${\gamma}$ -trimethyl-ammoniumbutyric acid) is a small water-soluble molecule important in mammalian fat metabolism. It is essential for the normal oxidation of fatty acids by the mitochondria, and is involved in the trans-esterification and excretion of acyl-CoA esters. In this paper, to investigate the relationship between aging and L-camitine, we investigated the effects of in vitro MMP inhibition and activity and expression of UVA-induced MMP 1 in human skin fibroblasts. Fluorometric assays of the proteolytic activities of MMP-l were performed using fluorescent collagen substrates. ELISA (enzyme linked immuno sorbent assay), gelatin-substrate zymography, and RT-PCR ELISA techniques were used for the effects of L-camitine on MMP expression and activity, MMP mRNA expression in UVA irradiated fibroblast. L-camitine inhibited the activities of MMP-l in a dose-dependent manner and the $IC_{50}$/ values calculated from semi-log plots were 2.45mM, and L-carnitine showed strong inhibition on MMP-2 (gelatinase) activity in UVA irradiated fibroblast by zymography. Also, UVA induced MMP expression was reduced 40% by treated with L-carnitine, and MMP-l mRNA expression was reduced dose-dependent manner. Therefore L-carnitine was able to significantly inhibition the MMP activity, regulation of MMP expression in protein and mRNA level. All these results suggest that L-carnitine may be useful as new anti-aging cofactor for protection against UVA induced MMP expression and activity.

• Journal of IKEEE
• /
• v.21 no.1
• /
• pp.24-29
• /
• 2017

In this paper, we have developed the nano carbon tile and chip which is based on a reducing process of oxidation and the viscous fluid control, after hardening to the stylene monomer and methylol acrylamide monomer using an acrylic emulsion junction material. Then we can obtain the sphere form structure of diagonal 1~3 mm, they have mixture the acrylic emulsion junction material(45%) and the coconut carbon powder(55%) of size 300~500 mesh for 25~30 min. Finally, if we have dry for the formated carbon including 30~90 minute at $90{\sim}300^{\circ}C$, then be obtained for pure carbon formation of 95%. In order to identify the safety of the friendly circumstance carbon formation, we have tested the far-infrared ratio, energy analysis, gas density and anti-disease germs experiment.

• Journal of Life Science
• /
• v.21 no.9
• /
• pp.1266-1273
• /
• 2011

Saponin is a main component of ginseng widely known as an oriental traditional medicinal ingredient. A variety of biological effects of saponin has been reported, but its action related to skin regeneration has remained unclear so far. In this study, the effect of saponin on matrix metalloproteinase as well as its antioxidant effect in cell free system was examined in human dermal fibroblasts. First of all, as a result of investigating the effect of saponin on cell viability using MTT assay, it was shown to increase cell viability below 10 ${\mu}g$/ml, but it also showed cytotoxicity above 25 ${\mu}g$/ml. The antioxidant effect of saponin was exerted by inhibition of $H_2O_2$ in addition to reducing power above 1 ${\mu}g$/ml. In particular, saponin showed a protective effect on DNA oxidation. Furthermore, it was observed that saponin activates MMP-2 and increases MMP-1 activity in gelatin and casein zymography analyses, respectively, indicating that saponin could have potential a therapeutic agent for anti-aging and skin regeneration.

• Journal of the Korea Convergence Society
• /
• v.8 no.4
• /
• pp.123-129
• /
• 2017

This study has been conducted to see influence of fibroid hepatic tissue on alpha-tocopherol and its histologic changes. Experimental groups were divided into 3 groups, one where fibrosis was caused by carbon tetrachloride and the other where alpha-tocopherol and carbon tetrachloride were administered together and another normal group. Results of test showed fibrosis reaction is weak compared to the group administered with carbon tetrachloride in the group administered with alpha-tocopherol. In conclusion, we could observe proliferation of collagen fibers through Hematoxylin&Eosin and Massom trichrom dye and increase in ALT, AST, ALP in fibroid hepatic tissues, indicating convergence anti-oxidation reaction by changes of alpha-tocopherol intake. Thus, it is considered that we can expect to utilize alpha-tocopherol as secondary treatment and find clinical meanings of diagnosis on hepatic diseases through results of this study.

• Biomolecules & Therapeutics
• /
• v.11 no.4
• /
• pp.224-231
• /
• 2003

The aim of this study was to investigate the effect of resveratrol on the oxidative stress-induced inhibition of gap junctional intercellular communication in HaCaT keratinocytes. Anti-oxidative activity of resveratrol was measured by $\alpha,\alpha$-diphenyl-$\beta$-picrylhydrazyl assay and dichlorodihydrofluorescein diacetate oxidation assay. Gap junctional intercellular communication in HaCaT keratinocytes was assessed using the scrape loading/dye transfer technique. Western blots and reverse transcription-polymerase chain reaction were also analyzed for connexin 43 protein and mRNA expression, respectively. Resveratrol scavenged directly the stable $\alpha,\alpha$-diphenyl-$\beta$-picrylhydrazyl radical over a concentration range of 4 mg/ml ($78.2{\pm}2.7$% of control) to 500 mg/ml ($29.9{\pm}4.2$% of control) and decreased the intracellular reactive oxygen species induced by ultraviolet A (UVA) irradiation ($89.3{\pm}1.1$% of UVA group), ultraviolet B (UVB) irradiation ($70.9{\pm}1.7$% of UVB group) and 12-0-tet-radecanoylphorbol-13-acetate (TPA, $48.3{\pm}1.1$% of TPA group), respectively. UVA irradiation and TPA markedly reduced gap junctional intercellular communication, which was restored by resveratrol. There were no significant differences in the level of connexin 43 protein and mRNA expression among any of the experimental groups. Our data suggests that resveratrol has the protective effect on the oxidative stress-induced inhibition of gap junctional intercellular communication in HaCaT keratinocytes, and this protection is likely due to the scavenging of reactive oxygen species.

• Archives of Pharmacal Research
• /
• v.28 no.12
• /
• pp.1358-1364
• /
• 2005

In this study, we investigated whether a novel anti-ischemic $K_{ATP}$ opener KR-31378 [(2S,3S,4R)­N'-cyano-N-(6-amino-3,4-dihydro-3-hydroxy-2 -methly-2-dimethoxymethly-2H-benzopyran-4-yl)­N'-benzylguanidine] has protective effect against oxidative stress-induced death in heart-derived H9c2 cells. Cell death was induced by BSO, butionine sulfoximine, which inhibits GSH synthesis and subsequently increases reactive oxygen species (ROS) level. Cell death was quantitatively determined by measuring lactate dehydrogenase (LDH) activity and stained by Hoechst 33258. BSO-induced ROS production and mitochondrial membrane potential (MMP) were measured using 2',7'-dichlorofluorescein diacetate oxidation and rhodamine 123, respectively. Both the LDH release and the ROS elevation induced by treatment of H9c2 cells with 10 mM BSO, were significantly decreased by KR-31378. These protective effect and antioxidant effect of KR-31378 appeared to be independent on $K_{ATP}$ channel opening. Cells exposed to BSO showed an early reduction in MMP, and this reduction in MMP was significantly reversed by treatment with KR-31378. Caspase-3 activity in BSO treated H9c2 cells was remarkably increased, and this increased caspase-3 activity was significantly reversed by KR-31378. In conclusion, our results suggest that KR-31378 can produce cardioprotective effect against oxidative stress-induced cell death through antioxidant mechanism.

• Journal of the Microelectronics and Packaging Society
• /
• v.26 no.3
• /
• pp.51-57
• /
• 2019

To protect the Cu surface from oxidation in air, a two-step plasma process using Ar and $N_2$ gases was studied to form a copper nitride passivation as an anti-oxidant layer. The Ar plasma removes contaminants on the Cu surface and it activates the surface to facilitate the reaction of copper and nitrogen atoms in the next $N_2$ plasma process. This study investigated the effect of Ar plasma on the formation of copper nitride passivation on Cu surface during the two-step plasma process through the full factorial design of experiment (DOE) method. According to XPS analysis, when using low RF power and pressure in the Ar plasma process, the peak area of copper oxides decreased while the peak area of copper nitrides increased. The main effect of copper nitride formation in Ar plasma process was RF power, and there was little interaction between plasma process parameters.