• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.17-24
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• 2005

Local treatment for tumors has developed from extended radical surgery to function preserving surgery on the basis of modern biology. With the development of minimally invasive technique, it changed to be minimal-invasive surgery. And nowadays technical revolution made non-invasive surgery possible with appearance of several kinds of non-surgical knives such as gamma knife, cyber knife, and HIFU (high intensity focused ultrasound) knife. In this article, history, HIFU machine and treatment procedure, histological change and its mechanism, clinical applications, advantage, disadvantage, and future prospect of extracorporeal high intensity focused ultrasound therapy using HIFU knife will be reviewed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.3
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• pp.185-189
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• 2001

In this paper, since the research on the etching of SrBi$_2$Ta$_2$$O_{9}$(SBT) thin film was few (specially Cl$_2$-base) we had studied the surface reaction of SBT thin films. We have used the OES(optical emission spectroscopy) in high density plasma etching as a function of RF power, dc bias voltage, and Cl$_2$/(Cl$_2$+Ar) gas mixing ratio. It had been found that the etch rate of SBT thin films appeared to be more affected by the physical sputtering between Ar ions and surface of the SBT compared to the chemical reaction. The change of Cl radical density that was measured by the OES as a function of gas combination showed the change of the etch rate of SBT thin films. Therefore, the chemical reactions between Cl radical in plasma and components of the SBT enhanced to increase the etch rates SBT thin films. These results were confirmed by XPS(x-ray photoelectron spectroscopy) analysis.s.

• Journal of Oriental Neuropsychiatry
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• v.21 no.1
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• pp.1-11
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• 2010

Objectives: This study was perfomed to investigate the antioxidant activity and serotonin activity of Gami-guibi-tang on P815 Mast Cell. Methods: The effects of Gami-guibi-tang on activation of TPH-1 mRNA and AAADC mRNA in P815 mast cell were investigated. The effect of Gami-guibi-tang on content of serotonin in P815 mast cell was investigated. The effects of Gami-guibi-tang on activation of DPPH radical scavenging and SOD in P815 mast cell were investigated. Results: 1. The Gami-guibi-tang increased SOD activity and DPPH radical scavenging activity. 2. The Gami-guibi-tang increased the intracellular concentration of serotoninin 60 ${\mu}g/ml$, 80 ${\mu}g/ml$ experiment group. 3. The Gami-guibi-tang increased menaingful the manifestation TPH mRNA. 4. The manifestation of AAADC and MAO mRNA have not made menaingful changes on Gami-guibi-tang. Conclusions: This experiment shows that Gami-guibi-tang had significant anti-oxidative effect. And Gami-guibi-tang increased the intracellular concentration of serotonin. Therefore, Gami-guibi-tang can be used by the medication of major depression disorder. But Study on mechanism of increased serotonin and clinical research of Gami-guibi-tang is suggested for future research.

• Korean Journal of Pharmacognosy
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• v.36 no.1 s.140
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• pp.38-43
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• 2005

This study was undertaken to evaluate the gastrotherapeutic effects of the extract of Rosa rugosa. It can be regarded that the antigastric and anti-ulcerative effect of Rosa rugosa is originated from the reduction of total acid output identified by gastric secretion test. To clarify the protective mechanism of the Rosa rugosa extract, the gastropathy was induced in rats with alcohol-salicylate and the activities of the free radical scavenging enzymes were examined. The acitivity of superoxide dismutase and glutathione peroxide were significantly increased and the total content of glutathione was recovered. We concluded that the protective effect of the extract of Rosa rugosa on gastropathy in rats is its ability increased the activities of the free radical scavenging enzymes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.236-241
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• 2010

The purpose of this study was to investigate the mechanism of ethanol extract of Agrimonia pilosa Ledeb. (EAP)-reduced melanogenesis and diphenyl-picryl-hydrazyl (DPPH) radical scavenging activity. Agrimonia pilosa Ledeb., a perennial herbaceous plant, has been used as an antihemorrhagic, anthelminntic, and antiinflammatory agents in Chinese herbal medicine. In the present study, we observed that melanin synthesis and tyrosinase activity of B16F10 cells were significantly decreased by EAP. However, EAP could not suppress tyrosinase activity in the cell-free system, whereas kojic acid directly inhibited tyrosinase activity. Furthermore, EAP decreased the protein expression of tyrosinase, tyrosinase-related prootein 1 (TRP-1), and tyrosinase-related prootein 2 (TRP-2). EAP scavenged DPPH radical up to 41% with 100 ${\mu}g/m{\ell}$ concentration. These results suggest that the hypopigmentary effect of EPA was due to regulation of tyrosinase protein.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.953-958
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• 2013

Selaginella tamariscina is a traditional herb used in medicine. Phytochemical amentoflavone, a biflavonoid class of flavonoids, was isolated from the plant of Selaginella tamariscina. In this study, the antibacterial effects and combination effects of amentoflavone and conventional antibiotics such as ampicillin, cefotaxime, and chloramphenicol were investigated. These results showed that amentoflavone had a considerable antibacterial effect and synergistic interaction with antibiotics against various bacterial strains (fractional inhibitory concentration index ${\leq}$ 0.5), except for Streptococcus mutans. To study the mechanism(s) involved in the synergistic activities between amentoflavone and antibiotics, we detected hydroxyl radical formation using 3'-(p-hydroxyphenyl) fluorescein and measured the $NAD^+/NADH$ ratio by $NAD^+$ cycling assay. The results indicated that the formation of hydroxyl radical would be a cause of the synergistic effect and that this oxidative stress originated from a transient NADH depletion. This study suggests that amentoflavone synergizes with antibiotics and has potential as a therapeutic agent for antimicrobial chemotherapy.

• International Journal of Oral Biology
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• v.34 no.1
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• pp.15-20
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• 2009

In our present study, total methanol extracts prepared from B. platyphylla var. japonica showed a significant increase in cell proliferation upon the induction of oxidative stress by hydrogen peroxide or $\gamma$-ray irradiation. Total methanol extracts were fractionated into five separate preparations i.e. n-hexane, dichloromethane, ethylacetate, n-butanol and water fractions. Among these, the ethylacetate and butanol fractions of B. platyphylla var. japonica showed the highest protective effects against oxidative stress induced by hydrogen peroxide. These fractions also showed strong protective effects against $\gamma$-ray irradiation. When we evaluated the cytotoxicity of these fractions, the butanol fraction showed no effects in a colony formation assay. In addition, the butanol fraction showed a cell proliferation activation effect evidenced by significant increase in the colony formation of $\gamma$-ray irradiated cells. Both a radical scavenging activity and clonogenic activity assay suggested that the mechanism behind this protective effect against reactive oxygen species may be due to the radical scavenging and cell proliferation activity of B. platyphylla var. japonica extracts.

• KSBB Journal
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• v.28 no.1
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• pp.36-41
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• 2013

Carotenoids are fat-soluble red-orange colored pigments found in plants and seafood-derived products, including algae, seaweeds, and fish muscle. In this study, we have demonstrated the molecular mechanism underlying the antioxidants and anti-inflammatory properties of ascidian tunic carotenoids using mouse macrophage cell line (RAW 264.7). Cell viability was not affected by treatment of carotenoids < 10 ${\mu}g/mL$. This treatment also showed negative inhibition on lipopolysaccharide (LPS)-stimulated nitric oxide (NO) and cyclooxygenase-2 (COX-2). The DPPH radical scavenging activity of carotenoids was 47.2% at 100 mg/mL. It also has a potential reducing power (1.025) comparable with ascorbic acid (1.584). The ascidian tunic carotenoids would make a candidate for the commercially interesting biologically active cosmetic pigments.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2973-2978
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• 2009

The decomposition reaction mechanism of $CH_3CF_2O$ radical formed from hydroflurocarbon, $CH_3CHF_2$ (HFC-152a) in the atmosphere has been investigated using ab-initio quantum mechanical methods. The geometries of the reactant, products and transition states involved in the decomposition pathways have been optimized and characterized at DFT-B3LYP and MP2 levels of theories using 6-311++G(d,p) basis set. Calculations have been carried out to observe the effect of basis sets on the optimized geometries of species involved. Single point energy calculations have been performed at QCISD(T) and CCSD(T) level of theories. Out of the two prominent decomposition channels considered viz., C-C bond scission and F-elimination, C-C bond scission is found to be the dominant path involving a barrier height of 12.3 kcal/mol whereas the F-elimination path involves that of a 28.0 kcal/mol. Using transition-state theory, rate constant for the most dominant decomposition pathway viz., C-C bond scission is calculated at 298 K and found to be 1.3 ${\times}$ 10$^4s{-1}$. Transition states are searched on the potential energy surfaces involving both decomposition channels and each of the transition states are characterized. The existence of transition states on the corresponding potential energy surface are ascertained by performing Intrinsic Reaction Coordinate (IRC) calculation.

• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.91-97
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• 1990

Copolymers (PSAA) of styrene-acrylic acid were prepared through a free radical mechanism using azobisisobutyronitrile as an initiator. The fluorescence emission spectra of PSAA and the styrene-acrylic acid copolymers complexed with $Eu^{3+}$ (PSAA-Eu) were studied. The excimer fluorescence, centered at 330 nm, increases when the styrene mole fraction increases. Since the excimer fluorescence intensities of PSAA-EU, PSAA-Tb and PSAA-Eu-Tb were almost same, it appears that the kind of metal ion does not affect the excimer fluorescence. An interpretation of the results which takes into account the statistical composition of the copolymers, indicates that energy migration can occur from isolated to non-isolated styrene units.