• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.1050-1054
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• 2005

Recently, arsenic compounds were considered as novel agents for treatment of acute promyelocytic leukemia and malignant tumors. However, it showed severe toxicity effect on normal tissue at the same time. In this study, to investigate the possible molecular mechanism (s) of arsenic compounds as candidate of anti-cancer drugs, we compared the abilities of two arsenic compounds, tetraarsenic oxide $(AS_4O_6)$ and arsenic trioxide (diarsenic oxide, $As_2O_3$), to induce cell growth inhibition as well as apoptosis induction in A549 human non-small cell lung cancer cells. Both $As_4O_6\;and\;As_2O_3$ treatment declined the cell growth and viability of A549 cells in a concentration-dependent manner, which was associated with induction of G1 arrest of the cell cycle and apoptotic cell death. However, $As_4O_6$ induced growth inhibition and apoptosis in A549 cells at much lower concentrations than $As_2O_3.\;As_4O_6$ down-regulated the levels of anti-apoptotic Bcl-2 protein, however, the levels of Bax, a pro-apoptotic protein, were up-regulated in a dose-dependent manner. In conclusion, $As_4O_6$ might be a new arsenic compound which may induce apoptosis in A549 cells by modulation the Bcl-2 family and deserves further evaluation.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.494-502
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• 2018

Breast cancer is currently the most prevalent cancer in women, and its incidence increases every year. Azole antifungal drugs were recently found to have antitumor efficacy in several cancer types. They contain an imidazole (clotrimazole and ketoconazole) or a triazole (fluconazole and itraconazole) ring. Using human breast adenocarcinoma cells (MCF-7 and MDA-MB-231), we evaluated the effects of azole drugs on cell proliferation, apoptosis, cell cycle, migration, and invasion, and investigated the underlying mechanisms. Clotrimazole and ketoconazole inhibited the proliferation of both cell lines while fluconazole and itraconazole did not. In addition, clotrimazole and ketoconazole inhibited the motility of MDA-MB-231 cells and induced $G_1$-phase arrest in MCF-7 and MDA-MB-231 cells, as determined by cell cycle analysis and immunoblot data. Moreover, Transwell invasion and gelatin zymography assays revealed that clotrimazole and ketoconazole suppressed invasiveness through the inhibition of matrix metalloproteinase 9 in MDA-MB-231 cells, although no significant changes in invasiveness were observed in MCF-7 cells. There were no significant changes in any of the observed parameters with fluconazole or itraconazole treatment in either breast cancer cell line. Taken together, imidazole antifungal drugs showed strong antitumor activity in breast cancer cells through induction of apoptosis and $G_1$ arrest in both MCF-7 and MDA-MB-231 cells and suppression of invasiveness via matrix metalloproteinase 9 inhibition in MDA-MB-231 cells. Imidazole drugs have well-established pharmacokinetic profiles and known toxicity, which can make these generic drugs strong candidates for repositioning as antitumor therapies.

• Molecular & Cellular Toxicology
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• v.2 no.3
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• pp.202-211
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• 2006

Our objective is to identify molecular factors which contribute to the increased risk of smoke in human. About 677 workers who had control and experimental groups according to their urinary Naphthol levels were enrolled in our study. In the present study, we investigated the effects of smoking on gene expression profiles in human. We determined differential gene expression patterns in smoker versus non-smoker using cDNA microarray. Specific genes were up-or down-regulated according to smoking and age. Inflammatory related genes such as cytokine, interleukin, and tumor necrosis factor were up-regulated, DNA repair related genes such as high-mobility group (nonhistone chromosomal) protein 1, and protein 2 were down-regulated, apoptosis related genes such as myeloperoxidase and Bcl-2-associated athanogene were down-regulated, and cell cycle related genes were down-regulated. In our epidemiological study, notably, inflammatory, DNA repair, apoptosis, signal transduction, metabolism, cell cycle, cell proliferation, transcription related genes were regulated.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.177-186
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• 1998

While tubal pregnancy is frequently observed in human, it has been reported to rarely occur in other mammals. To investigate the reason of the absence of tubal pregnancy in other mammals, the ability of bovine tubal(oviductal) fluid to su, pp.rt the outgrowth of mouse embryos waw examined by using an in vitro model system wherein the trophoblast cells of hatched mouse blastocysts attach to and outgrow on tissue culture plates coated with FBS. When mouse blastocysts grwon in vitro from 2-cell embryos were cultrued in the dishes coated with FBS, human follicular fluid(hFF) and bovine follicular fluid(bFF), respectively, underwent outgrowth by spreading onto the plastic dishes during 48 hr. In contrast, none of the embryos cultured in the dishes coated with BSA or bovine obiductal fluid(bOF) did outgrow but remained as late blastocysts. Since addition of bOF at 5mg/ml or higher conc. to the culture medium resulted in degeneration of all embryos during 48 hr culture, 10mM conc. of glutathione(GSH) was added to the bOF-containing medium to circumvent the toxicity of bOF. In addition, bOF was heated $65^{\circ}C$ for 30 min(hbOF) to get rid of its precipitating properties and then added to the culture medium. When blastocysts were cultured in the presence of both hbOF and GSH 45.4% of embryos attached to the culture dishes. However, none of these embryos underwent outgrowth. Fially embryos were cultured in the presence of both hbOF and GSH but in the dishes coated with FBS. When they were examined after 48 hr, all of the blastocysts exhibited well-developed outgrwoth. Based upon these results, it is concluded that bovine oviductal fluid is capable of su, pp.rting the attchment of mouse blastocysts onto the culture plaste whereas it cannot promote the outgrwoth of mouse blastocysts in vitro, probably due to the lack of outgrwoth factor.

• Journal of Pharmaceutical Investigation
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• v.22 no.3
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• pp.185-196
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• 1992

To assess its suitability as a prodrug of 5-fluorouracil (5-FU), 1-glycyloxymethyl-5-FU HCl (GFU), a 5-fluorouracil derivative having a glycyloxymethyl group at the N-l position was synthetized. Its physicochemical properties and hydrolysis kinetics, in aqueous solution of pH $1{\sim}10$ and in the presence of human plasma or rat liver homogenate were studied. Its acute toxicity and antitumor activity against sarcoma 180 were also examined, GFU showed higher lipid/water partition coefficient than 5-FU. The calculated $pK_{\alpha}$ values of 5-FU and GFU were 8.02 and 7,20, respectively. The decomposition rates of GFU in aqueous solution showed a pH-dependence over the pH range used, which could be ascribed to solvent catalysed hydrolysis reaction at pH lower than 4,16 and to specific hydroxide ion hydrolysis reaction at pH higher than 4,16, The half-life of GFU was 6,9 min in 80% human plasma solution and less than 3 min in rat liver homogenate at $37^{\circ}C$, The $LD_{50}$ value of 5-FU was 240 mg/kg while that of GFU was 440.6 mg/kg (226 mg as 5-FU). Both of 5FU and GFU showed a strong antitumor activity, Therapeutic ratios of 5-FU and GFU were 3.07 and 3.55, respectively.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.123-126
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• 2002

Pollutants that are persistent, bioaccurnulative, and toxic have been linked to numerous adverse effects in human and animals, PBTs include heavy metals, polychlorinated biphenyls (PCBs), dioxins, polycyclic aromatic compounds (PACs) in addition to pesticides. This study focuses on toxic effects of the PBTs except pesticides on insects. Eight PBTs were selected from subgroups: three heavy metals (Pb, Hg, and Cd), two PCB mixtures (Aroclor mixtures 1 and 2), 2,3,7,8-tetrachlorodibenzo-p-dioxin, two monophenols (4-octylphenol and 4-nonylphenol), and tetrabutyltin, Beet armyworm, Spodoptera exigua, was used as test target insect species. Three physiological markers (metamorphosis, immune reaction, and follicle patency) were assessed in each exposure to different doses of the PCBs. Heat-shock proteins as molecular markers were also analyzed in response to the PCBs. All tested PBTs were toxic to metamorphosis from larvae to pupae when they were applied with diet. Two PCB mixtures were the most toxic compounds in this assay by giving significant toxicity at 0.005 ppm, while others had from 10 to 1000 ppm. Dioxin (0.1 ppb), tetrabutyltin (0.1 ppb), Pb (10 ppb), and Hg (0,01 ppb) were potent to inhibit immune reactions analyzed by inducing phenoloxidase activity and blocked phospholipase $A_2$ enzyme, Tetrabutyltin and dioxin significantly induced follicle cell patency, but their effects were lower than that of endogenous juvenile hormone, Dioxin, Pb, Hg, and Cd could induce the expression of heat shock proteins that were detected by immunoblotting against human HSP70 monoclonal antibody. HSP78 and HSP80 were upregulated in response to the PBTs. This expression was detected from the fat body and epidermis at as fast as 4h after injection. All these results clearly suggest that PBTs give significant ecotoxicity to insects that are valuable organisms in our environment.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.330-336
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• 2005

Lactococcus lactis A164 is a nisin Z-producing strain isolated from kimchi. Its antimicrobial spectrum has been found to be active against most Gram-positive bacteria tested, yet inactive against Gram-negative bacteria [3]. Accordingly, to overcome this drawback, the current study attempted to express human $\beta$-defensin-l (hBD-l), which kills both Gram-positive and Gram-negative bacteria in L. lactis AI64. When the hBD-l cDNA was introduced using a nisin Z-controlled expression cassette, the L. lactis A164 transformants grew very poorly, due to the bactericidal effect of the expressed hBD-l against the transformants. Therefore, a gene fusion system was designed to reduce the toxicity of the expressed heterologous protein against the host cells. As such, the hBD-l gene was fused to the DsbC- Tag of pET -40b(+), then introduced to L. lactis A 164. The transformants expressed an intracellular 35.6-kDa DsbC-hBD-l fusion protein that exhibited slight activity against the host cells, yet not enough to strongly inhibit the cell growth. To obtain the recombinant hBD-l, the DsbC-hBD-l fusion protein was purified by nickel-affinity column chromatography, and the DsbC-Tag removed by cleaving with enterokinase. The cleaved mature hBD-l exhibited strong bactericidal activity against E. coli JM109, indicating that the recombinant L. lactis A 164 produced a biologically active hBD-I. In addition, the recombinant L. lactis A 164 was also found to produce the same level of nisin Z as the wild-type.

• Analytical Science and Technology
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• v.18 no.3
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• pp.188-193
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• 2005

Three different oriental natural plants (Angelicae Dahuricae Radix, Sanguisorba Officinalis L, Euonymus alatus) were extracted with 70% methanol under refluxing for 4 hr in order to investigate their inhibitory effect on Matrix Metalloproteinase-9 (MMP-9) by a modified gelatin zymography, where only euonymus alatus showed the inhibitory effect on the activity of Matrix MMP-9. The fraction was collected by using the mixture of ethyl acetate and hexane on silica gel column. Seven portions were obtained and three fractions of them (first, third and forth) showed inhibitory effect on the zymography. To verify the effect of these substances on cells, human hepatoma, Hep3B cells as a cancer model, and Chang liver cells as a normal model were selected. In order to examine the cell viability, $1{\mu}g/mL$ of each extract was treated on cells. Most of the methanol soluble fractions showed negligible toxicity on human liver cell line.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.560-568
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• 2007

The aim of this study is to investigate the terminology of chemically unclear ‘heavy metals' which were expressed in the Korean secondary science textbook in terms of the definition, the type and the meaning. Initial results showed that six of ‘Chemistry I' textbooks among these texts defined a heavy metal with the density and described it as a metal which is hazardous and continuously accumulated in the human body. Specifically, cadmium, lead and mercury were presented as examples of the hazardous metal in all of the eight textbooks but non-metals such as arsenic and absolutely essential metals including chrome, manganese, iron, cobalt, nickel and copper were also given in the texts. Most of the texts described the hazardousness and toxicity of the metal too simple to understand the mechanism of its intoxication despite considering all of the factors including its oxidation state, residual amount and reactivity with biomolecules of the human body. Such an ambiguous definition and explanation may excluded in the textbook because the chemically undefined chemical vocabulary leads students to cause an alternative conception of the heavy metal, which means that the metal could be identical with toxins.

• The Journal of Pediatrics of Korean Medicine
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• v.29 no.2
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• pp.26-36
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• 2015

Objectives In this study, effect of Geumsuyukgunjeon (GYJ) on the increase in airway epithelial mucosubstances of rats with acute bronchitis and EGF-induced MUC5AC mucin production from human airway epithelial cells were investigated. Materials and Methods Hypersecretion of airway mucus was induced by exposure of rats to SO2 during 3 weeks. Effect of orally-administered GYJ during 2 weeks on increase in airway epithelial mucosubstances from tracheal goblet cells of rats was assesed using histopathological analysis after staining the epithelial tissue with PAS-alcian blue. Possible cytotoxicity of GYJ was assessed by examining the potential damage of kidney and liver functions by measuring serum GOT/GPT activities and serum BUN and creatinine concentrations of rats and the body weight gain during experiment, after administering GYJ orally. Effect of GYJ on EGF-induced MUC5AC mucin production from human airway epithelial cells (A549) was investigated. Confluent A549 cells were pretreated for 30 min in the presence of GYJ and treated with EGF (25 ng/ml) for 24 hrs, to assess the effect of GYJ on EGF-induced MUC5AC mucin production using enzyme-linked immunosorbent assay (ELISA). Results (1) GYJ decreased the amount of intraepithelial mucosubstances of trachea of rats. (2) GYJ did not show kidney and liver toxicities and did not affect body weight gain of rats during experiment. (3) GYJ significantly inhibited EGF-induced MUC5AC mucin production from A549 cells. Conclusions The result from the present study suggests that GYJ might control both the mucus hypersecretion in vivo and do not show in vivo toxicity to liver and kidney functions after oral administration and the production of pulmonary mucin.