• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.366-370
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• 1989

A new macrocyclic ligand 1,15,18-triaza-3,4;12,13-dibenzo-5,8,11-cycloeicosane (NdienOdien$H_4$ = $N_3O_3$) has been synthesized and identified by element analysis, NMR and IR spectrophotometry. Stepwise protonation constants of ligand are determined by potentiometry in 95% methanol solution(I = 0.1 mol $dm^{-3}$, $Me_4$NCl). log $K_1$;log $K_2$;log $K_3$ = 9.1;8.1;3.6.The kinetics of the acid-promoted dissociation reactions of complex cations of nickel(II) and copper(III) with NdienOdien and NdienOen macrocyclic ligands having, respectively, 17 and 20 ring members, have been studied spectrophotometrically in HCl$O_4$ NaCl$O_4$ aqueous solutions. From the temperature effect on kinetic constant ($k_{obs}$), the parameters of activation(${\Delta}H^{\neq}$, ${\Delta}S^{\neq}$) of dissociation reaction for $ML^{2+}$ with $H^+$ ion have been determined. We have proposed the possible mechanism of the reaction from the data obtained.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1478-1484
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• 2009

The antioxidant, antiproliferation, and nitrate synthesis inhibitory effects of Magnolia denudata extracts (ME) were evaluated. The ME was extracted with 70% (v/v) ethanol and fractionated with solvents of hexane, chloroform, ethyl acetate, n-buthanol and aqueous. The ethyl acetate fraction contained the highest phenolic and flavonoid contents of 427.10 mg garlic acid eq/g and 356.05 mg catechin eq/g, respectively. The ethyl acetate fraction showed strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity with a 50% inhibition concentration ($IC_{50}$) of 0.20 mg/mL and total antioxidant activity was 0.90 mg AA eq/100 mg. From the results of cytotoxic effects of HCT116, NCL-H460, and HepG2 human cancer cells by MTT assay on the ME and its solvent fraction, chloroform fraction showed the highest cytotoxic effect ($IC_{50}$ value: 0.14, 0.37, and 0.41 mg/mL, respectively). Nitrate synthesis inhibitory effect of ME and its solvent fractions on nitric oxide synthase activity in LPS stimulated RAW 264.7 cells were decreased in dose-dependent manners, and $IC_{50}$ value of hexane and chloroform fractions were 0.39 and 0.49 mg/mL, respectively.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.463-474
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• 2002

Background : This study was designed to examine how glutathione, one of the nucleophilic sulfur compounds, effects the cisplatin cellular toxicity in the non-small cell lung cancer cell lines and normal lung epithelial cell line. Materials and Methods : Three cultured cell lines, the lung adenocarcinoma cell(NCL-H23), the lung squamous carcinoma cell(SK-MES-1) and the normal lung epithelial cell(L-132) line were exposed to various concentrations of cisplatin with or without glutathione. The relative viability was estimated as a means of measuring the cisplatin cellular toxicity using the MTT method. Results : In NCI-23, the response to cisplatin was sensitive but glutathione markedly increased the relative survival of the tumor cells by removing the antitumor effect of cisplatin. In both SK-MES-1 and L-132, the responses to cisplatin were less sensitive, and the chemoprotective effect of glutathione compared to and equal cisplatin dose was significantly higher in L-132 than in SK-MES-1(p<0.05). Conclusion : The protective effectes of of glutathione on cisplatin-induced cellular toxicity is more significant in normal lung epithelial cells than in squamous carcinoma cells.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.275-284
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• 2002

Background : Gemcitabine is a new anti-cancer agent for treating non-small cell lung cancer. Functioning as an antimetabolite, it induces anti-cancer effects by suppressing DNA synthesis after being incorporated into the DNA as a cytosine arabinoside analogue. When Gemcitabine is incorporated into the DNA, the p53 gene may be activated by induction of the DNA defect. However, there are a few studies on the molecular mechanisms of Gemcitabine-induced cell death. This study examined the role of p53 in Gemcitabine-induced cell death. Methods : A549 and NCl-H358 lung cancer cells were used in this study. The cell viability test was done using a MTT assay at Gemcitabine concentrations of 10nM, 100nM, 1uM, 10uM and 100uM. A FACScan analysis with propium iodide staining was used for the cell cycle analysis. Western blot analysis was done to investigate the extent of p53 activation. For the functional knock-out of p53, stable A549-E6 cells and H358-E6 cells were transfected pLXSN-16E6SD which is over expresses the human papilloma virus E6 protein that constantly degrades p53 protein. The functional knock out of p53 was confirmed by Western blot analysis after treatment with a DNA damaging agent, doxorubicine. Results : Gemcitabine exhibited cell toxicity in dose-dependent fashion. The cell cycle analysis resulted in an S phase arrest. Western blot analysis significant p53 activation in time-dependent manner. Gemcitabine-induced cytotoxicity was reduced by 20-30% in the A549-E6 cells and the 30-40% in H358-E6 cells when compared with the A549-neo and H358-neo control cells. Conclusion : Gemcitabine induces an S phase arrest, as expected for the anti-metabolite, and activates the p53 gene, Furthermore, p53 might play an important role in Gemcitabine-induced cell death. Further investigation into the molecular mechanisms on how Gemcitabine activates the p53 gene and its signaling pathway are recommended.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.659-668
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• 1993

Background: p53 is currently considered as a tumor suppressive gene product, and its alterations are suggested to be involved in several human malignancies, including non-small cell lung cancers. p53 expression rates are variable in many reports and among cell types. Also, whether the phase of p53 expression is early or late during carcinogenesis is not certain. Thus, We have investigated to evaluate p53 expression rates of the various cell types and tissues and identify expression phase (early or late). Method: We obtained 71 tissue from 50 non-small cell lung cancer patients and performed the simple immunohistochemical staining using nonspecific monoclonal antibody(NCL-p53DO7). Results: 1) In non-small cell lung cancer patients. the expression rate of lungs(46.5%) is higher than that(25.0%) of lymph nodes. But, there is no significant difference between two groups. 2) Among the various cell types, p53 expression rates in squamous cell carcinoma and adenocarcinoma are 58.3% and 50.0% respectively without significant difference. 3) p53 expression rates in various stages are 33.3%, 60.0%, 40.0%, 60.0% and 66.7% in stage I, II, IIIa, IIIb and IV, respectively with no significant difference. 4) p53 expression rates in the various T parameters are 33.3%, 50.0%, 16.7% and 100% in T1, T2, T3 and T4, respectively and p53 expression rates in the various N parameters are 27.3%, 22.2% and 25.0% in N1, N2 and N3, respectively. There are no significant differences in the expression rates among varous T & N parameters. 5) p53 expression rates of lymph nodes in patients who have positive stains in lungs are 12.5% and 50.0% in N1 and N2. 6) p53 expression rates of all lymph nodes in patients who have negative stains in lungs are 0.0%. Conclusion: The above results show that p53 expression rate in non-small cell lung cancers is not correlated with cell type and progression of stage and it is thought to need further investigations about at what phase p53 expression influences the development and progression of lung cancers.