• BMB Reports
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• v.28 no.4
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• pp.293-300
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• 1995

The radical centers detected in the reaction of metmyoglobin (MetMb) with hydrogen peroxide ($H_2O_2$) have been studied by using a spin trapping technique. A broad 5-line asymmetric electron spin resonance (ESR) spectrum, with $2A_{max}=4.07\;mT$ and $2A_{min}=2.97\;mT$, obtained after incubation of MetMb with $H_2O_2$ in the presence of a spin trap, 5,5-dimethyl pyrroline-N-oxide (DMPO) was gradually weakened with time and disappeared completely by 6 min after addition of guanidine-HCl (14 M). When a higher concentration (6 M) of the agent was added, the signal disappeared within 40 see and the DMPO/OH signal appeared immediately. Then, a new 8-line signal with similar intensities grew gradually and was fixed by 45 min, coexisting with the DMPO/OH signal. This new signal was found to be composite, consisting of two different radical species. One of the 6-line signals, with $a_N$ 1.49 mT and $a_H$ 0.988 mT, was assigned to the DMPO/phenoxyl radical adduct. The second 6-line signal with $a_N$ 1.55 mT and $a_H$ 2.22 mT was assigned to carbon-centered radical adduct. When 3,3,5,5-tetramethylpyrrolin-N-oxide (TMPO), was employed in the place of DMPO, another broad asymmetric 5-line signal was detected with $2A_{max}=3.99\;mT$ and $2A_{min}=3.04\;mT$, which is virtually identical to that obtained from the DMPO system The shape of the spectrum of the TMPO adduct changed drastically, with lapse of time resulting in a broad singlet after 40 min. The broad singlet was assigned to the porphyrin radical adduct. Incubation of globin with Fenton reagent in the presence of DMPO initially gave a DMPO/OH signal. Then, a new 12-line signal began to grow after one minute and fixed after 15 min. coexisting with the DMPO/OH signal, This 12-line signal was assigned to DMPO/phenoxyl with $a_N$ 1.47 mT, $a_{{\beta}H}$ 0.99 mT and $a_{{\gamma}H}$ 0.13 mT. A minor concentration of carbon-centered radical adduct was also detected. This radical composition is identical to that of guanidine HCl treated MetMb/DMPO/$H_2O_2$ system, indicating that the radical producing conditions are somehow common in both systems. Heme iron can be released by excess $H_2O_2$ in the MetMb/$H_2O_2$ system, providing for Fenton reagent. When MetMb was pretreated with tyrosine blocking agent, $KI_3$ the broad 5.line MetMb-derived signal was not detected in the MetMb/DMPO/$H_2O_2$ system, whereas no such effect was detected on such system of Hb in which the radical center was assigned to cysteine residue not tyrosine, indicating that tyrosine residue is a main radical center produced in the MetMb/$H_2O_2$ system Thus, the present data strongly support the previous indication that the apomyoglobin-derived radical center formed in the reaction of MetMb with $H_2O_2$ is a tyrosine residue.

• Journal of the Korean Electrochemical Society
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• v.10 no.3
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• pp.184-189
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• 2007

The importance of secondary battery industry is getting excited according to the development of battery industry as a high efficiency energy supplier of electronic machine of mobile information such as mobile phone, lap-top computer, PDA. It is rasing the interest about security of safety and high efficiency of cathode material for main part of secondary lithium battery. The cathode material which has been used like $LiCoO_2,\;LiMn_2O_4,\;LiNi_xCo_yMn_zO_2,\;LiNi_xCo_yM_zO_2$ (M=Al, Zr, Mg etc.,) the most typical material is $LiCoO_2$. But it is studying the development of substitute such as efficiency amelioration of $LiCoO_2$, thetiary element, olivine element because of the capacity of $LiCoO_2$, the matter of security; especially the betterment of efficiency, security research of safety has been actively processed in domestic and overseas about surface coating treatment of active cathode which is using oxide ($M_xO_3$). This study analyses side effect of battery according to increase of surface treatment, formation of precipitation for reagent condensation, non-reagent residue of oxide ($M_xO_3$) which is remains during the surface treatment of $LiCoO_2$; conducts study of new process, the consideration of the electrochemical property to improve oxide solution of mixing rate, mixture of surface treatment, dryness, calcinations conditionetc.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.159-164
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• 2015

To identify new anti-inflammatory and whitening material, this study investigated the whitening and anti-inflammatory effects of the lyophilized powder from 6 oriental plant extracts (OPE; Citrus junos Tanaka, Mori cortex Radicis, Schisandra chinensis Baillon, Coix lachrymajobi var. mayuen, Angelica gigas NAKAI, and Sophora japonica L.) fermented with Streptococcus thermophilus by assessment of cytotoxicity on human dermal fibroblast, inhibitory effect of nitric oxide (NO) prodction, tyrosinase activity and melanin formation. The OPE was fermented with Streptococcus thermophilus at $37^{\circ}C$ for 2 days and the lyophilized powder was manufactured by freezing-dryer. OPE didn't show cytotoxicity at concentration of $500{\mu}g/mL$ using a cytopathic effect reduction method. OPE also exhibited inhibitory effect on nitric oxide (NO) prodction by Griess reagent system. Furthermore, OPE showed inhibitory effect on tyrosinase activity with dose dependent manner, and exhibited significant inhibition of melanin formation by measurement of melanin from culture media (p < 0.05). From these results, 6 OPE extracts showed anti-inflammatory and whitening effect and may be used as an active ingredient for cosmetics.

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.23-28
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• 2015

Objectives : The aim of this study is to investigate cell viability, anti-inflammatory, antioxidant, immunoenhancing activity using various extracts of Yeonsan Ogye.Methods : In order to evaluate cytotoxicity, MTT assay was performed. We investigated production levels of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-αand interleukin (IL)-6, and nitric oxide(NO) in LPS-induced RAW 264.7 cells. NO production in RAW 264.7 cells was measured by using Griess reagent. Cytokines including IL-6 and TNF-αwere measured by Luminex and ROS was measured by Flow cytometry.Results : No cytotoxicity of various extracts of Yeonsan Ogye was observed in RAW 264.7 cells. Productions of ROS in RAW 264.7 cells were increased from extraction of bones and decreased from extraction of skin. Also, productions of NO in RAW 264.7 cells were increased to bone extract and decreased at skin extract. In addition, productions of pro-inflammatory cytokines (IL-6 and TNF-α) in LPS-induced RAW 264.7 cells were decreased at skin, meat extracts, respectively. Finally, the levels of immune-related cytokines (IL-6 and TNF-α) were increased compared to those of the normal group.Conclusions : It is concluded that Yeonsan Ogye extracts seem to have significant biological activities likes anti-inflammatory, antioxidant, immuno-enhancing etc. These results may be developed as a raw material for new health food and new therapeutics to ease the symptoms related with inflammatory and oxidative stress. In terms of oriental traditional medicine, we expect that it contribute to building of EBM (Evidence-Based Medicine) from the this result.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.139-146
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• 2020

Kastle-Meyer (KM) test is one of presumptive tests used to detect latent blood in crime scenes. While this method is more sensitive than others, false positive reaction can be shown where blood does not exist. In this study, we tried to suggest a new application method to solve this problem. Reaction time and aspect of reaction of this new method was compared with two conventional methods in order to identify the effectiveness and identifiability. As a result, there was no statistically significant difference in sensitivity between the methods. In addition, in case of blood with a dilution ratio of 5000:1 or less, positive reaction showed immediately, making it easy to distinguish the reaction from false positive reaction. However, it became difficult to distinguish them with the reaction time as the dilution ratio increased, and this phenomenon could be supplemented observing aspect of the reaction when using the new method. Therefore, this study suggested a new method for KM test that can be used more accurately in the field.

• Analytical Science and Technology
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• v.14 no.6
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• pp.499-503
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• 2001

A new simple, rapid and sensitive gas chromatographic technique for the determination of bisphenol-A in can materials, which is the major material of epoxy resin and polycarbonate polymer, is proposed. This method is characterised by derivatization of the bisphenol-A with a acylating reagent forming the acetate derivative to optimize the chromatographic property. The detection of bisphenol-A is performed based on GC/MS (gas chromatography/mass spectrometry). Several beverages were analyzed by the proposed method for the determination of bisphenol-A Bisphenol-A was assayed the range of $0.11{\sim}11.40{\mu}g/can$ from the can materials.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1018-1023
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• 2001

Oleamide (cis-9-octadecenamide) is endogenous primary amide of fatty acid that is produced in small amounts in animal brains. It is known to induce sleep and to lower temperature by destroying the lipid plasma membrane structure of cells, thereby disclosing gap junction channels. To develop a new biological production method for oleamide, a screening program was conducted to isolate a microorganism producing oleamide. Among 1,500 soil microorganisms tested, KK90378 exhibited a potent positive reaction with Dragendoff`s reagent, used to detect the primary amide of oleamide. KK90378 was identified as a Streptomyces species based on cultural and morpohological characteristics, the presence of diaminopimelic acid in the cell wall, and the sugar patterns for the whole-cell extrat. Streptomyces sp. KK90378 produced oleamide 3 days after culture at $28^{\circ}C$, pH 7.2 A series of purification steps, including hexane extraction, silica gel column, and preparative thin layer chromatographies, were performed for the purification of oleamide. A spectrophotometric analysis using $^1H$, $^13C$-NMR, and GC-MS confirmed that the chemical structure of the purified oleamide was identical to that of authentic oleamide.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2569-2574
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• 2015

Necroptosis, also known as "programmed necrosis", has emerged as a critical factor in a variety of pathological and physiological processes and is considered a cell type-specific tightly regulated process with mechanisms that may vary rather greatly due to the change of cell line. Here we used HT-29, a human colon cancer cell line, to establish a necroptosis model and elucidate associated mechanisms. We discovered that cobalt chloride, a reagent that could induce hypoxia-inducible $factor-1{\alpha}(HIF1{\alpha})$ expression and therefore mimic the hypoxic microenvironment of tumor tissue in some aspects induces necroptosis in HT-29 cells when caspase activity is compromised. On the other hand, apoptosis appears to be the predominant death form when caspases are functioning normally. HT-29 cells demonstrated significantly increased RIPK1, RIPK3 and MLKL expression in response to cobalt chloride plus z-VAD treatment, which was accompanied by drastically increased $IL1{\alpha}$ and IL6 expression, substantiating the notion that necrosis can induce profound immune reactions. The RIPK1 kinase inhibitor necrostatin-1 and the ROS scavenger NAC each could prevent necrosis in HT-29 cells and the efficiency was enhanced by combined treatment. Thus by building up a necroptosis model in human colon cancer cells, we uncovered that mechanically RIP kinases collaborate with ROS during necrosis promoted by cobalt chloride plus z-VAD, which leads to inflammation. Necroptosis may present a new target for therapeutic intervention in cancer cells that are resistant to apoptotic cell death.

• Advances in aircraft and spacecraft science
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• v.4 no.6
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• pp.729-744
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• 2017

This investigation highlights rationale of electrically conductive nano adhesives for its essential application for Electromagnetic Interference (EMI) Shielding in satellites and Lightning Strike Protection in aircrafts. Carbon Nano Fibres (CNF) were functionalized by electroless process using Tollen's reagent and by Plasma Enhanced Chemical Vapour Deposition (PECVD) process by depositing silver on CNF. Different weight percentage of CNF and silver coated CNF were reinforced into the epoxy resin hardener system. Scanning Electron Microscopy (SEM) micrographs clearly show the presence of CNF in the epoxy matrix, thus giving enough evidence to show that dispersion is uniform. Transmission Electron Microscopy (TEM) studies reveal that there is uniform deposition of silver on CNF resulting in significant improvement in interfacial adhesion with epoxy matrix. There is a considerable increase in thermal stability of the conductive nano adhesive demonstrated by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Four probe conductivity meters clearly shows a substantial increase in the electrical conductivity of silver coated CNF-epoxy composite compared to non-coated CNF-epoxy composite. Tensile test results clearly show that there is a significant increase in the tensile strength of silver coated CNF-composites compared to non-coated CNF-epoxy composites. Consequently, this technology is highly desirable for satellites and EMI Shielding and will open a new dimension in space research.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.583-593
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• 1995

The present study was conducted to develop a toxoplasma latex agglutination test antigen(Test-MT) and evaluate the toxoplasma latex agglutination(LA) test using a newly-made "Test-MT kit" by comparing with the Toxo-MT kit(Eiken chemical co, Tokyo). Also, the specifity and sensitivity test were made by comparing with IFA test and IgG-ELISA. Tachyzoite suspensions of Toxoplasma gondii(RH strain) were ultracentrifuged for 30min at $60,000{\times}g(4^{\circ}C)$ and the supernatant was used as a water-lysate antigen. Polystyrene latex particles of $1.0{\mu}m$ in diameter(Polyscience co) were used for the preparation of sensitized latex-antigen supension(Test-MT). The frequency distribution of LA titers in Test-MT showed two peaks at <1:32 and 1:128. The borderline titer for positive test in Test-MT was determined to be 1:64. But the frequency distribution of LA tites in Toxo-MT showed two peaks at <1:16 and 1:64. The positive borderline was determined to be 1:32. Agreement of reactions between Test-MT and Toxo-MT kit by LA test was shown 92.5% in bovine sera and 97.0% in swine sera, respectively. From the results obtained here it was determined that the sensitized latex-antigen, Test-MT kit, for the microtiter agglutination test prepared as same as by the procedure described in the previous paper(Suh and Lee, 1993) was useful as a highly specific, sensitive and stable immunotiteration reagent for serodiagnosis of toxoplasma infection in animal sera.