• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.606-610
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• 2010

Aminoacyl-tRNA synthetases (aaRSs) play vital roles in protein biosynthesis of living organisms and are interesting antibacterial drug targets. In order to find out new inhibitor candidate molecules as antibacterial agent, the binding modes of the candidate molecules were investigated at the active sites of aaRSs by molecular docking study. The docking simulations were performed with 48 compounds from four different scaffolds into the eight different aaRSs. The results show that scaffolds 3 and 4 compounds have consistently better binding capabilities, specifically for HisRS (E. coli) and IleRS (S. aureus). The binding modes of the best compounds with the proteins were well compatible with those of two ligands in crystal structures. Therefore, we expect that the final compounds we present may have reasonable aaRS inhibitory activity.

• Journal of Life Science
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• v.25 no.8
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• pp.849-860
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• 2015

The anti-cancer activities of Rhus verniciflua Stokes (GC), Ulmus davidiana var. japonica Nakai (UGP) and arsenium sublimatum (SS) extracts, which have been used Oriental medicine therapy for various diseases, were investigated. The treatment of GC, UGP and SS alone, and combined treatment with GC, UGP and SS did not affect the cell viability in the mouse normal cell lines (RAW 264.7 macrophages and C2C12 myoblasts). However, co-treatment with GC, UGP and SS markedly induces apoptosis in human gastric cancer AGS cells, but not in other various cancer cell lines (human lung cancer A549, colon cancer HCT116, liver cancer Hep3B and bladder T24 cells) as evidenced by formation of apoptotic bodies, chromatin condensation, and accumulation of annexin-V positive cells. Co-treatment with GC, UGP and SS effectively induced the expression levels of Fas and Fas ligand, and inhibited the levels IAP family proteins such as XIAP, cIAP-1 and survivin, and anti-apoptotic Bcl-xL proteins compared with treatment with either agent alone. Combined treatment also significantly induced the loss of mitochondrial membrane potential, which was associated with the activation of caspases (-3, -8, and -9) and degradation of poly (ADP-ribose) polymerase. However, the cytotoxic effects induced by co-treatment with GC, UGP and SS were significantly attenuated by pan-caspases inhibitor, z-VAD-fmk, indicating an important role for caspases. These results indicated that the caspases were key regulators of apoptosis in response to co-treatment of GC, UGP and SS in human gastric cancer AGS cells and further studies will be needed to identify the active compounds.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2421-2427
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• 2013

Background: To study the response rate, toxicity profiles, and survival of refractory or recurrent epithelial ovarian cancer (EOC) patients treated with paclitaxel. Materials and Methods: Patients with refractory or recurrent EOC who were treated with paclitaxel between January 2002 and December 2011 at the Department of Obstetrics and Gynecology, Faculty of Medicine, Vajira Hospital were identified. Clinicopathological features of the patients including detailed data of paclitaxel treatment were collected. Results: During the study period, a total of 44 patients were identified, with a mean age of $52.9{\pm}8.2$ years. Some 13.6% (six patients) had refractory cancer to first-line chemotherapy while 86.4% (38 patients) had recurrent cancer. Among these, 35 (79.6%) and 9 (20.4%) patients were considered as platinum-sensitive and platinum-resistant, respectively. Three patients (6.8%) received fewer than 2 cycles of paclitaxel due to loss to follow-up, leaving 41 patients evaluable for response. The overall response rate observed in all 41 patients was 41.5% (17 patients; 12 complete and five partial responses): 12.5% or 1/8 patients with refractory or platinum-resistant cancer and 48.5% or 16/33 patients with platinum-sensitive disease. Stable disease was demonstrated in 17.0% (seven patients) while progressive disease was apparent in 41.5% (17 patients). Median time to progress was 4.5 months (range, 0.67-58.6 months). Median progression-free survival was not reached while median overall survival was 16.3 months (95% confidence interval, 11.0 months -21.6 months). Common toxicities were neutropenia, neuropathy, and alopecia. Conclusions: Paclitaxel is an active agent for refractory or recurrent EOC. Neutropenia, neuropathy and alopecia are common side effects.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.279-284
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• 2013

The phenolic beads in macrosize range were obtained by suspension polymerization at $98^{\circ}C$ from phenol and formaldehyde in the presence of basic catalyst with a phenol to formaldehyde (P/F) range of 1:1~1:4, and they were carbonized to spherical carbon beads under nitrogen at $700^{\circ}C$. Thermal analysis on spherical phenolic beads obtained by suspension polymerization showed that the postcuring process is essential. In order to optimize the suspension polymerization, the effects of the P/F molar ratio, the pH of catalyst, and the molecular weight of stabilizer on the size distribution and yield of spherical phenol beads were examined separatively. The particle size was increased whereas the yield was decreased with P/F molar ratio. The increasing basicity of catalyst made the particle size to increase, while the molecular weight of stabilizer had more effect on the yield rather than on the particle size distribution. The thermal stability of the spherical phenolic beads obtained through postcure was also examined by TGA. The phenol beads of high P/F ratio still showed the weight loss at $220^{\circ}C$ even after postcure due to the high possibility of dibenzyl ether, while those of low P/F ratio showed the steady decrease in weight during $220^{\circ}C$ to $400^{\circ}C$, which showed that the optimal P/F ratio was 1:2.

• Journal of dental hygiene science
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• v.6 no.3
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• pp.153-158
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• 2006

Bleaching of vital and nonvital teeth is becoming a more commonly used treatment in the dental office and at home. To improve appearance and remove discoloration, the teeth of specific patients are treated with a variety of bleaching agents. The typical bleaching agents contains carbamide or hydrogen peroxide as the active component. The purpose of the review article was to summarize and discuss the available information concerning the effect of peroxide releasing bleaching agent on dental restorative materials and restorations. Information from all original scientific full papers or reviews listed in PubMed or ISI Web Science were included in the review. Bleaching may exert a negative influence on restorations and restorative materials. Advice is provided based on the current literature to minimize the impact of bleaching treatment on restorative materials and restorations.

• Journal of Life Science
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• v.28 no.2
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• pp.216-222
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• 2018

Desmodium heterocarpon is one of vines belongs to Fabaceae family, mainly distributed in Asian countries such as Korea and Japan. This study was conducted to explore new nutraceutical resources from the plant kingdom possessing biological activities. To fulfill this purpose, the anti-oxidative and anti-inflammatory activities of D. heterocarpon ethanol extract (DHEE) were evaluated by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity assay, reactive oxygen species (ROS) scavenging activity assay, nitric oxide (NO) inhibitory activity assay, and the analysis of related protein expressions by Western blot hybridization. DHEE exhibited potent anti-oxidative activity as confirmed by DPPH radical scavenging capacity against DPPH similar with ascorbic acid, a well-known anti-oxidative agent, used as a positive control. DHEE also effectively suppressed hydrogen peroxide ($H_2O_2$)-induced ROS on RAW 264.7 murine macrophage cells. Furthermore, DHEE induced the expression of the anti-oxidative enzyme heme oxygenase 1 (HO-1), and its upstream transcription factor, nuclear factor-E2-related factor 2 (Nrf2) as a dose dependent manner. DHEE inhibited lipopolysaccharide (LPS) induced nitric oxide (NO) formation as a consequence of inducible NO synthase (iNOS) down regulation. Taken together, these results suggest that DHEE has anti-oxidative and anti-inflammatory activities and thus appears to be useful sources as potential anti-oxidant and anti-inflammatory agents. The identification of active compounds that confer biological activities of DHEE might be needed.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1323-1334
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• 2010

The effect of nitric oxide (NO) on antioxidant system and protective mechanism against oxidative stress under UV-B radiation was investigated in leaves of maize (Zea mays L.) seedlings during 3 days growth period. UV-B irradiation caused a decrease of leaf biomass including leaf length, width and weight during growth. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated UV-B stress induced growth suppression. NO donor permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under UV-B stress, suggesting that NO has protective effect on chloroplast membrane in maize leaves. Flavonoids and anthocyanin, UV-B absorbing compounds, were significantly accumulated in the maize leaves upon UV-B exposure. Moreover, the increase of these compounds was intensified in the NO treated seedlings. UV-B treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in maize leaves, while NO donor prevented UV-B induced increase in the contents of malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that NO serves as antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, catalase (CAT) and ascorbate peroxidase (APX) in maize leaves in the presence of NO donor under UV-B stress were higher than those under UV-B stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3- oxide (PTIO), a specific NO scavenger, to the maize leaves arrested NO donor mediated protective effect on leaf growth, photosynthetic pigment and free radical scavenging activity. However, PTIO had little effect on maize leaves under UV-B stress compared with that of UV-B stress alone. $N^{\omega}$-nitro-L-arginine (LNNA), an inhibitor of nitric oxide synthase (NOS), significantly increased $H_2O_2$ and MDA accumulation and decreased antioxidant enzyme activities in maize leaves under UV-B stress. This demonstrates that NOS inhibitor LNNA has opposite effects on oxidative resistance. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative stress induced by UV-B radiation and thus confer UV-B tolerance.

• Korean Journal of Social Welfare
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• v.64 no.2
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• pp.85-109
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• 2012

This qualitative study explored a middle-aged lesbian's life and her identities by the oral life history approach in feminist epistemology, where the participant is not the object but the subject of knowledge. The participant kept her own perspective that her homosexuality was not intrinsic but constructed. In her life's history, she was a "docile body" accepting socially constructed historical meaning of homosexuality, as well as a "resistant body" protesting against social discrimination and oppression for homosexual population. She overcame an embedded negative recognition of her scaled injured body and her sexuality as "deficient". Finally, she showed an amazing resilience and an indomitable spirit for reconstructing the meaning of her body as "blessed." Beyond the deficient body, as an active agent not the pathologic sexual minority, she could cultivate compassion and empathy for others. From the results, it is important how to place gender and sexuality in the context of social work theory and practice. Sexuality, not sexual orientation, is 'our' collective agenda to address the social problems which were associated with social hierarchy, inequality, and injustice.

• KSBB Journal
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• v.16 no.5
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• pp.486-492
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• 2001

The antimutagenic mechanism of the fraction III(RG III)separated from the water extract of Rehmannia glutionosa was investigated by Escherichia. coli GW and B/r strains. RG-III treatment did not affect the ${\beta}$-galactosidase activity E. coli GW-1060, 1106, 1107 and 1105. These results indicated that RG-III did not induce RecA protein amplification and did not also prevent the proteolytic cleavage of LexA. The bio-antimutagenicity and survival effect of RG-III on 4-nitroquinoline 1-oxide(4NQO), N-methyl-N-nitor-N\`-nitrosoguanidine(MNING) were investigate by E. coli B/r strains with have different pathway of DNA repai. RG-III slightly increased the survival of 4NQO-treated WP2, WP2s, WP67, CM561, CM611 cells, but the reactivation of survival cannot ve explained by the repair mode. RG-III caused the decrease of mutagenicity and lethality treated with MNNG in ZA159 despite of the increase in WP2, WP2s, WP67, CW561, CM611. Compared with bio-antimutagenic effects of RG-III on 4NQO, greatly increased antimutagenic effects of RG-III were observed with all the E. coli B/r strains tested, but less active in ZA159. These results suggest that RG-III was identified as a blocking agent for preventing the 4NQO induced mutagenesis, and may act as chl-products.

• BMB Reports
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• v.51 no.11
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• pp.572-577
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• 2018

Recent studies showed that the PD-1/PD-L1 checkpoint blockade is a dramatic therapy for melanoma by enhancing antitumor immune activity. Currently, major strategies for the PD-1/PD-L1 blockade have mainly focused on the use of antibodies and compounds. Seeking an alternative approach, others employ endogenous proteins as blocking agents. The extracellular domain of PD-1 (ePD1) includes the binding site with PD-L1. Accordingly, we constructed a PD-1-based recombinantly tailored fusion protein (dFv-ePD1) that consists of bivalent variable fragments (dFv) of an MMP-2/9-targeted antibody and ePD1. The melanoma-binding intensity and antitumor activity were also investigated. We found the intense and selective binding capability of the protein dFv-ePD1 to human melanoma specimens was confirmed by a tissue microarray. In addition, dFv-ePD1 significantly suppressed the migration and invasion of mouse melanoma B16-F1 cells, and displayed cytotoxicity to cancer cells in vitro. Notably, dFv-ePD1 significantly inhibited the growth of mouse melanoma B16-F1 tumor cells in mice and in vivo fluorescence imaging showed that dFv-ePD was gradually accumulated into the B16-F1 tumor. Also the B16-F1 tumor fluorescence intensity at the tumor site was stronger than that of dFv. This study indicates that the recombinant protein dFv-ePD1 has an intensive melanoma-binding capability and exerts potent therapeutic efficacy against melanoma. The novel format of the PD-L1-blocked agent may play an active role in antitumor immunotherapy.