• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.89-94
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• 2013

Layered $Li_{1+x}(Mn_{0.4}Ni_{0.4}Fe_{0.2})_{1-x}O_2$ (0 < x < 0.3) solid solutions were synthesized using solgel method with adipic acid as chelating agent. Structural and electrochemical properties of the prepared powders were examined by means of X-ray diffraction, Scanning electron microscopy and galvanostatic charge/discharge cycling. All powders had a phase-pure layered structure with $R\bar{3}m$ space group. The morphological studies confirmed that the size of the particles increased at higher x content. The charge-discharge profiles of the solid solution against lithium using 1 M $LiPF_6$ in EC/DMC as electrolyte revealed that the discharge capacity increases with increasing lithium content at the 3a sites. Among the cells, $Li_{1.2}(Mn_{0.32}Ni_{0.32}Fe_{0.16})O_2$ (x = 0.2)/$Li^+$ exhibits a good electrochemical property with maximum initial capacity of 160 $mAhg^{-1}$ between 2-4.5 V at 0.1 $mAcm^{-2}$ current density and the capacity retention after 25 cycles was 92%. Whereas, the cell fabricated with x = 0.3 sample showed continuous capacity fading due to the formation of spinel like structure during the subsequent cycling. The preparation of solid solutions based on $LiNiO_2-LiFeO_2-Li_2MnO_3$ has improved the properties of its end members.

• The Journal of Advanced Prosthodontics
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• v.7 no.2
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• pp.172-177
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• 2015

PURPOSE. The purpose of this study was to evaluate cell toxicity due to ion release caused by galvanic corrosion as a result of contact between base metal and titanium. MATERIALS AND METHODS. It was hypothesized that Nickel (Ni)-Chromium (Cr) alloys with different compositions possess different corrosion resistances when contacted with titanium abutment, and therefore in this study, specimens ($10{\times}10{\times}1.5mm$) were fabricated using commercial pure titanium and 3 different types of Ni-Cr alloys (T3, Tilite, Bella bond plus) commonly used for metal ceramic restorations. The specimens were divided into 6 groups according to the composition of Ni-Cr alloy and contact with titanium. The experimental groups were in direct contact with titanium and the control groups were not. After the samples were immersed in the culture medium - Dulbecco's modified Eagle's medium[DMEM] for 48 hours, the released metal ions were detected using inductively coupled plasma mass spectrometer (ICP-MS) and analyzed by the Kruskal-Wallis and Mann-Whitney test (P<.05). Mouse L-929 fibroblast cells were used for cell toxicity evaluation. The cell toxicity of specimens was measured by the 3-{4,5-dimethylthiazol-2yl}-2,5-diphenyltetrazolium bromide (MTT) test. Results of MTT assay were statistically analyzed by the two-way ANOVA test (P<.05). Post-hoc multiple comparisons were conducted using Tukey's tests. RESULTS. The amount of metal ions released by galvanic corrosion due to contact between the base metal alloy and titanium was increased in all of the specimens. In the cytotoxicity test, the two-way ANOVA showed a significant effect of the alloy type and galvanic corrosion for cytotoxicity (P<.001). The relative cell growth rate (RGR) was decreased further on the groups in contact with titanium (P<.05). CONCLUSION. The release of metal ions was increased by galvanic corrosion due to contact between base metal and titanium, and it can cause adverse effects on the tissue around the implant by inducing cytotoxicity.

• Journal of Life Science
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• v.25 no.4
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• pp.406-415
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• 2015

In this study, we investigated the antioxidant activities and compared other physiological properties including anti-cancer and antimicrobial effects of several traditional Korean herb-combined remedies such as Gilgyung-tang (GGT), Daihwangmokdan-tang (DHMDT), Sagan-tang (SGT), Socheonryongtang (SCRT), Sihocheonggan-tang (SHCGT), Sipyukmiyuki-eum (SYMYKE) and Hwangheuk-san (HHS), which were recorded in “Dong-eui-bo-gam” for “Ongjeo”. Total phenolic contents of the herb medicines were in a rich order of GGT ＜ SYMYKE ＜ SCRT ＜ SHCGT ＜ DHMDT ＜ SGT ＜ HHS. Among them, HHS appeared highest in superoxide dismutase-like activity, ferric reducing antioxidant power, scavenging of 2,2’-diphenyl-1-picrylhydrazyl, and 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical activity. Interestingly, there was a positive relationship between their total phenolic contents and their antioxidant activities. Although all of them showed anti-proliferative activities in human colon cancer HCT-116 cells, HHS was seven times higher than GGT. Antimicrobial activities against Escherichia coli and Helicobacter pylori were revealed only on SGT, SCRT, SYMYKE and HHS. Taken together, these findings reveal the potential use of traditional Korean herbal formulas as functional ingredients in antioxidant and physiological materials.

• Journal of Life Science
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• v.17 no.11
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• pp.1497-1504
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• 2007

To investigate the function and secretion of human thrombopoietin (TPO) in mammalian cells, hTPO cDNA was cloned using human liver cDNA, and recombinant hTPO (rec-hTPO) was produced in CHO cell lines. In addition, six N-linked glycosylation sites were substituted for Ala to elucidate the role of each carbohydrate chain. To analyze the biological activity, rec-hTPO protein was injected subcutaneously. Blood was withdrawn for platelet determination. The metabolic clearance rate (MCR) was also analyzed at the 1, 4, 10 and 24 hr after tail vein injection. Wild-type TPO (WT) was efficiently secreted into the medium. However, a hTPO mutant with 116 deleted nucleotides detected by PCR cloning was not secreted. The N-linked glycosylation sites had nearly the same expression quantity as rec-hTPO WT apart from mutants 3 and 4. The glycosylation site of mutant 4 appeared to be an indispensable site for hTPO secretion. Also characterized was the biological activity through an injection with rec-hTPO (10 ng) to ICR mice (7 weeks). The result of the blood analysis showed a considerable increase in the platelet number six days after He injection. To analyze the pharmacokinetics, rec-hTPO was injected into the tail vein (5 ng). The result was 200 pg/ml 1hr after this injection. Following this, it dramatically decreased and virtually disappeared 10 hours after the injection. Thus, rec-hTPO may be a treatment for thrombopenia by the production of the high active rec-hTPO. In addition, hTPO can permit the development of potent new analogues that stimulate the platelet value.

• Journal of Life Science
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• v.21 no.9
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• pp.1219-1225
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• 2011

Phytochemicals, non-nutrient chemicals derived from plants, have been shown to have anti-inflammation, anti-oxidation, and chemopreventive effects. In the current study, we investigated whether five different phytochemicals (resveratrol, genistein, epicatechin gallate, diallyl disulfide, and caffeic acid phenethyl ester) alter cell growth and gene expression in human colorectal cancer HCT116 cells. Using a cell viability assay, we found that each of the phytochemicals tested inhibited HCT116 cell growth in a dose-dependent manner. Additionally, using human oligo DNA microarray analysis, we found that only six genes were commonly up-regulated and seven genes were commonly down-regulated in response to each phytochemical treatment. For the commonly up-regulated genes, the microarray analysis was confirmed by reverse transcription.PCR using gene-specific primers. In addition, NAG-1 protein was up-regulated by all treated phytochemcials. The results of this study may help to enhance our understanding of the general molecular mechanisms of chemoprevention that are mediated by phytochemicals in human colorectal cancer.

• Journal of Life Science
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• v.22 no.10
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• pp.1399-1406
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• 2012

The present study was conducted to evaluate the effects of various extracts of Hizikia fusiforme on the anti-obesity effects in 3T3-L1 preadipocytes. We used H. fusiforme extracts from ethanol (EEHF), dichloromethane (CFHF), ethyl acetate (EAFHF), butanol (BFHF), and water (WFHF). Treatment with these extracts significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet content through Oil Red O staining; this effect was higher in WFHF than in other extracts. The concentrations of cellular triglyceride were also reduced in 3T3-L1 cells by exposure with these extracts, especially when compared with the controls. Treatment with 200 ${\mu}g/ml$ of WFHF and CFHF caused approximately 42.6% and 23.7% reduction, respectively. In addition, the extracts of H. fusiforme significantly reduced the expression levels of key pro-adipogenic transcription factors, including peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer binding proteins ${\alpha}$ (C/$EBP{\alpha}$) and C/$EBP{\beta}$ as compared with controls. Accordingly, our data indicated that WFHF has a preeminent effect on inhibition of adipocyte differentiation among various extracts, and H. fusiforme extracts may be an ideal candidate for obesity relief.

• Korean Journal of Medicinal Crop Science
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• v.17 no.6
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• pp.397-406
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• 2009

The low quality fresh ginseng was extracted by water at $80^{\circ}C$ and 240 bar for 20 min (HPE, High pressure extraction process). The cytotoxicity on human normal kidney cell (HEK293) and human normal lung cell (HEL299) of the extracts from HPE showed 28.43% and 21.78% lower than that from conventional water extraction at $100^{\circ}C$ in adding the maximum concentration of $1.0\;mg/m{\ell}$. The human breast carcinoma cell and lung adenocarcinoma cell growth were inhibited up to about 86%, in adding $1.0\;mg/m{\ell}$ of extracts from HPE. This values were 9-12% higher than those from conventional water extraction. On in vivo experiment using ICR mice, the variation of body weight of mice group treated fresh ginseng extracts from HPE of 100 mg/kg/day concentration was very lower than control and other group. The extracts from HPE was showed longer survival times as 35.65% than that of the control group, and showed the highest tumor inhibition activities compared with other group, which were 70.64% on Sarcoma-180 solid tumor cells. On the high performance liquid chromatogram (HPLC), amount of ginsenoside-$Rg_2$, $Rg_3$, $Rh_1$ and $Rh_2$ on fresh ginseng were increased up to 43-183% by HPE, compared with conventional water extracts. These data indicate that HPE definitely plays an important role in effectively extracting ginsenoside, which could result in improving anticancer activities. It can be concluded that low quality fresh ginseng associated with this process has more biologically compound and better anticancer activities than that from normal extraction process.

• Tuberculosis and Respiratory Diseases
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• v.54 no.6
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• pp.628-634
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• 2003

Bronchiectasis is defined as an abnormal, irreversible dilatation of the bronchi, which may result from a number of possible causes, and the recognition of these causes may lead to a specific management strategy. Immunodeficiency is known as one of the conditions associated with bronchiectasis. X-linked agammaglobulinemia is a rare inheritable immunodeficiency disorder, caused by a differentiation block, leading almost to the complete absence of B lymphocytes and plasma cells. The affected protein is a cytoplasmic protein tyrosine kinase, Bruton's tyrosine kinase. The early detection and treatment with immunoglobulin replacement are most important for the management of recurrent infections and for reducing severe complications. We report a 20-year-old male patient, with X-linked agammaglobulinemia associated with bilateral bronchiectasis, carrying a missense mutation(R520P) in the BTK gene.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.489-496
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• 2004

Insertion of cannulae into vessels may disturb the blood flow doing non-physiological load and stress on blood cells such that ADP may increase and result in hemolysis. Authors used the computational method to simulate the 3-dimensional blood flow inside of the cannula using numerical method. We limited the research to within the drainage cannulae with side holes inserted through the human vein. In this paper, 9 different cannulae with side holes categorized by the number of side holes of 4, 12, and 20, and also categorized by the array type of side holes of staggered array, in-line array, and alternative in-line array were studied and compared to the cannula with no side holes by using CFD analysis. We evaluated the flow rate, the wall shear stress, and the shear rate and compared them with one another to estimate the effect of the side holes. The flow rate is not proportional to the number of the side holes. However, larger number of side holes can reduce the mean shear rate. Both the number and the array type of side holes play an important role on the fluid dynamics of the blood flow in cannulae.

• Journal of Pharmaceutical Investigation
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• v.29 no.3
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• pp.217-225
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• 1999

These studies were designed to determine the effect of hydroalcoholic gel system (lower alkanol concentration: 40-60%) compared to general hydrogel system (lower alkanol concentration: 10-35%) on transdermal delivery of piroxicam and its anti-inflammatory activity. Piroxicam was incorporated into a hydroalcoholic gel and a hydrogel containing polymers, solvents, and cosolvents. The pH of gel was about 6.3-7.3 and the solvent mixtures were composed of water and various concentrations of ethanol (35, 40, 50, and 60%). For the in vitro study, the skin permeation of piroxicam from the gel formulations was investigated using Franz modified diffusion cells fitted with hairless mouse skin. For the in vivo study, the anti-inflammatory activity of hydroalcoholic gel was compared to other commercial products (piroxicam hydrogel and ketoprofen hydrogel) in rat and human. The anti-inflammatory activity was determined using carrageenan induced foot edema model in rat. For the clinical study, it was evaluated from determining efficacy and acceptability with 98 patients suffering from musculoskeletal pain. A novel piroxicam hydroalcoholic gel was successfully formulated in the range of 40-50% of ethanol as solvent, more than 10% of propylene glycol, 5% of $Transcutol^{\circledR}$ and 1 % of benzyl alcohol. The skin permeation of piroxicam using hydroalcoholic gel system was greater than that of general hydrogel system $(flux\;:\;139.1-148.2\;{\mu}g/cm^2/hr\;vs.43.0-84.5 {\mu}g/cm^2/hr)$ in vitro. In carrageenan-induced edema model, the anti-inflammatory activity of hydroalcoholic gel was better than that of piroxicam hydrogel for edema inhibition (75.1 % vs. 62.9%, p