• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.234-240
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• 2016

The effect of initial electrolyte loading (IEL) on cell performance in a coin-type molten carbonate fuel cell (MCFC) was investigated in this work. Since the material of MCFC depends on the manufacturer, optimisation requires experimental investigation. In total, four IEL values, 1.5, 2.0, 3.0, and 4.0 g, were used, corresponding to a pore filling ratio (PFR) of 38, 51, 77, and 102%, respectively. The cell performance with respect to the PFR was analysed via steady-state polarisation, step-chronopotentiomtery, and impedance methods. The electrochemical analyses revealed that internal resistance and overpotential of the cell decreased with increasing PFR, and a large overpotential was observed when the PFR was 102%, probably due to the flooding phenomenon. After operation, cross-section of the cell was analysed via surface analysis of SEM and EDS methods, and the remaining electrolyte was estimated by dissolution of the cell in 10 wt% acetic acid. A linear relationship between IEL and the weight reduction ratio by dissolution was obtained. Thus, the remaining amount of electrolyte could be measured after operation. The results of SEM and EDS showed that a PFR of 38 and 102% showed a lack and flooding of electrolytes at the cell, respectively, which led to a large overpotential. This work reports that MCFC performance is allowed only in the narrow range of PFR.

• International Journal of Oral Biology
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• v.36 no.3
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• pp.129-134
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• 2011

Eugenol is an essential oil found in cloves and cinnamon that is used widely in perfumes. However, the significant anesthetic and sedative effects of this compound have led to its use also in dental procedures. Recently, it was reported that eugenol induces apoptosis in several cancer cell types but the mechanism underlying this effect has remained unknown. In our current study, we examined whether the cytotoxic effects of eugenol upon human melanoma G361 cells are associated with cell cycle arrest and apoptosis using a range of methods including an XTT assay, Hoechst staining, immunocyto-chemistry, western blotting and flow cytometry. Eugenol treatment was found to decrease the viability of the G361 cells in both a time- and dose-dependent manner. The induction of apoptosis in eugenol-treated G361 cells was confirmed by the appearance of nuclear condensation, the release of both cytochrome c and AIF into the cytosol, the cleavage of PARP and DFF45, and the downregulation of procaspase-3 and -9. With regard to cell cycle arrest, a time-dependent decrease in cyclin A, cyclin D3, cyclin E, cdk2, cdk4, and cdc2 expression was observed in the cells after eugenol treatment. Flow cytometry using a FACScan further demonstrated that eugenol induces a cell cycle arrest at S phase. Our results thus suggest that the inhibition of G361 cell proliferation by eugenol is the result of an apoptotic response and an S phase arrest that is linked to the decreased expression of key cell cycle-related molecules.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8503-8512
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• 2016

The purpose of this study was to provide a detailed explanation of the mechanism of bisanthracycline, WP 631 in comparison to doxorubicin (DOX), a first generation anthracycline, currently the most widely used pharmaceutical in clinical oncology. Experiments were performed in SKOV-3 ovarian cancer cells which are otherwise resistant to standard drugs such as cis-platinum and adriamycin. As attention was focused on the ability of WP 631 to induce apoptosis, this was examined using a double staining method with Annexin V and propidium iodide probes, with measurement of the level of intracellular calcium ions and cytosolic cytochrome c. The western blotting technique was performed to confirm PARP cleavage. We also investigated the involvement of caspase activation and DNA degradation (comet assay and immunocytochemical detection of phosphorylated H2AX histones) in the development of apoptotic events. WP 631 demonstrated significantly higher effectiveness as a pro-apoptotic drug than DOX. This was evident in the higher levels of markers of apoptosis, such as the externalization of phosphatidylserine and the elevated level of cytochrome c. An extension of incubation time led to an increase in intracellular calcium levels after treatment with DOX. Lower changes in the calcium content were associated with the influence of WP 631. DOX led to the activation of all tested caspases, 8, 9 and 3, whereas WP 631 only induced an increase in caspase 8 activity after 24h of treatment and consequently led to the cleavage of PARP. The lack of active caspase 3 had no outcome on the single and double-stranded DNA breaks. The obtained results show that WP 631 was considerably more genotoxic towards the investigated cell line than DOX. This effect was especially visible after longer times of incubation. The above detailed studies indicate that WP 631 generates early apoptosis and cell death independent of caspase-3, detected at relatively late time points. The observed differences in the mechanisms of the action of WP631 and DOX suggest that this bisanthracycline can be an effective alternative in ovarian cancer treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3419-3424
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• 2014

Background: Our aim was to conduct a meta-analysis to compare the efficacy and safety of pemetrexed and docetaxel for non-small cell lung cancer (NSCLC). Materials and Methods: We systematically searched the Cochrane Library, PubMed, Embase, China Biology Medicine Database for randomized controlled trials (RCTs) comparing the efficacy and toxicities of pemetrexed versus docetaxel as a treatment for advanced NSCLC. We limited the languages to English and Chinese. Two reviewers independently screened articles to identify eligible trials according to the inclusion and exclusion criteria and assessed the methodological quality of included trials, and then extracted data. The meta-analysis was performed using STATA12.0. Results: Six RCTs involving 1,414 patients were identified. We found that there was no statistically significant differences in overall response rate, survival time, progression-free survival, disease control rate, and 1-2yr survival rate (p>0.050) but it is worthy of mention that patients in the pemetrexed arms had significantly higher 3-yr survival rate (P=0.002). With regard to the grade 3 or 4 hematological toxicity, compared with docetaxel, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, and leukocyts toxicity (p<0.001). There was no significant difference in anemia between the two arms (p=0.08). In addition, pemetrexed led to higher rate of grade 3-4 thrombocytopenia toxicity (p=0.03). As for the non-hematological toxicities, compared with docetaxel, pemetrexed group had lower rate of grade 3-4 diarrhea and alopecia. Conclusions: Pemetrexed was almost as effective as docetaxel in patients with advanced NSCLC. At the same time, pemetrexed might increase the 3-yr survival rate. As for safety, pemetrexed led to lower rate of grade 3-4 febrile neutropenia, neutropenia, leukocytes, diarrhea and alopecia toxicity. However, it was associated with a higher rate of grade 3-4 thrombocytopenia.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.883-888
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• 2012

Anode electrode is one of the most important factors in microbial fuel cell (MFC). This study was conducted to investigate the effects of mediator as methylene blue (MB) and electrode surface area on the power density of MFC with sponge and carbon nano tube (CNT) electrode (SC). The SC electrode with MB (MC) showed the maximum power density increased from 74.0 $mW/m^2$ to 143.1 $mW/m^2$. The grid shaped sponge and CNT (GSC) electrode showed the maximum power density of 209.2 $mW/m^2$ due to the increase of surface area from 88.0 to 152.0 $cm^2$. The GSC electrode with MB (GMC) revealed the maximum power density of 384.9 $mW/m^2$ which was 5.2 times higher than that obtained from the MFC with SC. Therefore MB and increase of surface area led to enhance the performance of microbial fuel cell such as power density.

• Korean Journal of Pharmacognosy
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• v.48 no.3
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• pp.213-218
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• 2017

In order to search for anticancer agent as therapy of oral squamous cell carcinoma (OSCC) and malignant pleural mesothelioma (MPM) from Korean traditional prescriptions, we selected 58 traditional prescriptions based on a review of the Korean traditional medicine books. Among the selected traditional prescriptions, only water extracts of paedoksan (敗毒散) showed relatively good cytotoxicity at the concentration of $50{\mu}g/ml$. Additionally, we evaluated cytotoxicity for various paedoksans and each herbal ingredient in paedoksans. The root of Anthriscus sylvestris exhibited more cytotoxic effect than any other ingredients in paedoksans. Bioactivity-guided fractionation of the MC layer of Anthriscus sylvestris led to the isolation of deoxypodophyllotoxin (DPT). DPT exhibited dose-dependently significant cytotoxicity against OSCC and MPM cell with nM range. Therefore, DPT from A. sylvestris might be a potential candidate as an effective anticancer therapeutic agent for OSCC and MPM.

• Journal of Nutrition and Health
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• v.32 no.7
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• pp.838-843
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• 1999

Antitumor effects of various teas have been studied for a long time. Among them, green tea is one of the most popular test and very close to our lives in Korea. However, precise effect and mechanism about antitumor effects of green tea were not estabilished. The present study investigated the antitumor effect of catechin, which is main component of green tea, which was produced in Korea, was used. In each group, morphological changes were observed induced severe cell damage and growth inhibition gradually until 24hours. Then catechin effect was found to be concentration-and time-dependent. EATC was injured abruptly at 100ug/ml catechin treatment for 6 hours and the effect lasted constantly until 24 hours. But in both of cell lines, cell damage and inhibition of proliferation did not show up apparently at concentration of 10 and 1ug/ml. In contrast, catechin led to little or no effect against HepG2 in all of concentrations and periods. These results suggest that catechin extracted from green tea had different effect on cancer cells as cell type, concentration and period. Therefore green tea would be helpful to cancer treatment as well as cancer prevention and this study would be the basic source for further research of green tea.

• Archives of Pharmacal Research
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• v.20 no.4
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• pp.379-383
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• 1997

Cyclosporin A, an potent immunosuppressant, has been known to be one of the modulators of drug resistance as well as a cytostatic drug. Despite many attempts to basic or clinical application of cyclosporin A, there are few reports on the inhibition of brain tumor cells. In the present experiment, the possibility of cyclosporin A as synergic adjuvant was investigated by MTT assay, $[^{3}H]$ thymidine uptake and through flowcytometric anaysis. Sole treatment of cyclosporin A on the CRT and CH235-MG glioma cell line revealed dose dependent cytotoxicity within a range of tested dose. Combined treatment of cyclosporin A with ACNU, BCNU and hydroxyurea on various glioma cancer cell line led to a significant synergistic cytotoxicity as well as inhibition of DNA synthesis with dose-dependency. In addition, cyclosporin A alone or combined treatment caused discernible changes of cell cycle in the tested cells. These data provide that cyclosporin A could potentiate the effect of nitrosourea compounds in vitro on human glioma cells.

• Journal of Environmental Health Sciences
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• v.38 no.1
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• pp.1-7
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• 2012

Carbon nanotubes (CNTs) stand at the frontier of nanotechnology and are destined to stimulate the next industrial revolution. Rapid increase in their production and use in the technology industry have led to concerns over the effects of CNT on human health and the environment. The prominent use of CNTs in biomedical applications also increases the possibility of human exposure, while properties such as their high aspect ratio (fiber-like shape) and large surface area raise safety concerns for human health if exposure does occur. It is crucial to develop viable alternatives to in vivo tests in order to evaluate the toxicity of engineered CNTs and develop validated experimental models capable of identifying CNTs' toxic effects and predicting their level of toxicity in the human respiratory system. Human lung epithelial cells serve as a barrier at the interface between the surrounding air and lung tissues in response to exogenous particles such as air-pollutants, including CNTs. Monolayer culture of the key individual cell types has provided abundant fundamental information on the response of these cells to external perturbations. However, such systems are limited by the absence of cell-cell interactions and their dynamic nature, which are both present in vivo. In this review, we suggested two viable alternatives to in vivo tests to evaluate the health risk of human exposure to CNTs.

• Journal of the Korean Electrochemical Society
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• v.2 no.3
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• pp.163-170
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• 1999

The effects of the operating conditions in AFC single cells have not been studied in detail. In this study, by using a one-dimensional isothermal model a computational simulation was conducted to investigate the effects of the initial electrolyte concentration and the operating gas pressure. According to the result, the optimum electrolyte concentration at the base-case was found to be within $3.0\~3.5$ M. The variation of the cell performance according to the electrolyte concentration was found to be caused mainly by the charge transfer resistances of both electrodes, Henry's constant and the liquid phase diffusivity of the dissolved gases. It was also found that an increase in operating pressure increased the reaction rates and the solubilities of the gases, which led to a considerable enhancement of the cell performance.