• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.103-114
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• 1995

Platinum coordination complexes are currently one of the most compounds used in the treatment of solid tumors. However, its use is limited by severe side effects such as renal toxicity. Our platinum-based drug discovery program is aimed at developing drugs capable of diminishing toxicity and improving antitumor activity. We synthesized new Pt (Ⅱ) complex analogue containing 1,2-diaminocyclohexane (dach) as carrier ligand and 1,2-bis(diphenylphosphino) ethane (DPPE) as a leaving group. Furthermore, nitrate was added to improve the solubility. A new series of [Pt(trans-ddach)(DPPE).$2NO_3(PC)$ was synthesized and characterized by their elemental analysis and by various spectroscopic techniques [infrared (IR), $^{13}carbon$ nuclear magnetic resonance (NMR)]. PC demonstrated acceptable antitumor activity aganist P388, L-1210 lymphocytic leukemia cells and SK=OV3 human ovarian adenocarcinoma cells, and significant. activity as compared with that. cisplatin. The toxicity of PC was found quite less than thar of cisplatin using MTT, $[^3H]$ thymidine uptake and glucose consumption tests in rabbit proximal tubule cells, human kidney cortical cells and human renal cortical tissues. Based on these results, this novel platinum compound represent a valuable lead in the development of a new anticancer chemotherapeutic agent capable of improving antitumor activity and low toxicity.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.171-180
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• 2006

Peroxisome proliferatorr-activated receptor-gamma $(PPAR{\gamma})$ must form a heterodimer with the retinoid-X receptor (RXR) to bind DNA, and its transcriptional activity is thought to be maximized by ligands specific for either receptor. Activated $(PPAR{\gamma})$ and $(PPAR{\gamma})$ ligands may influence tumor growth through regulation of the tumor suppressor PTEN. Our aim in this study was to determine whether co-stimulation with the $(PPAR{\gamma})$ ligand, ciglitazone, and RXR ligand can synergistically upregulate PTEN in human acute promyelocytic leukemia (APL) cells and consequently potentate the inhibition of cell growth and cell cycle progression of these cells. Human leukemia cell line, HL-60 cells were exposed to all-trans-retinol and ciglutazone. The PTEN expression was measured as the level of PTEN mRNA expression by RT-PCR and as the level of PTEN expression by western blot analysis. Cell cycle analysis was carried out by a propidium iodide (PI) staining method and analyzed with a FACScan. The $(PPAR{\gamma})$ ligand, ciglitazone, and the RXR ligand, retinoic acid, upregulated PTEN expression by HL-60 cells in time- and dose-dependent manners, respectively. This was significantly enhanced by a combination of both ciglitazone and retinoic acid. Moreover, these compounds synergistically induced arrests of both cell growth and the $G_l$ phase of the cell cycle. Thus, the activation of the $(PPAR{\gamma})$:RXR heterodimer may represent a regulatory pathway for human leukemia cells and there may be important roles for $(PPAR{\gamma})$ and RXR ligands in prophylactic and therapeutic approaches fur controlling leukemia through the upregulation of PTEN.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.743-750
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• 1999

Human and bovine dopamine transporters (DAT) demonstrate discrete functional differences in the dopamine (DA) transport and cocaine binding. The functional analyses on the chimeras of human and bovine DAT have revealed that the region from the $133^{rd}{\;}to{\;}186^{th}$ residue(encompassing the $3^{rd}$ trans-membrane domain (TM) is responsible for the substrate transport and cocaine binding. The present studies have been done to find out the specific amino acid(s) which is essential for the binding of cocaine to DAT by interchanging the amino acids in that region between human and bovine DAT. When isoleucine, the $152^{nd}$ residue of chimera B3 (bovine DAT sequence) was transformed back to valine, the human DAT residue at the identical position, the cocaine binding was remarkably recovered to 98% of the human DAT values. In addition, the cocaine binding of the human DAT was decreased by 57% by substituting isoleucine for valine at position 152. When isoleucine at position 152 of the chimera B3 was converted to the other amino acids to provide an possible molecular basis for the functional role of the $152^{nd}$ residue, only the conversion to alanine among acids tested significantly the cocaine by 34%, but these effect were not as much as those by the conversion to valine. In conclusion, valine at position 152 is a crucial amino acid for the interaction of cocaine to the DAT.

• Journal of the Korean Professional Engineers Association
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• v.22 no.2
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• pp.19-25
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• 1989

Utilizing a cosine transform in image compression has several recognized performance benefits, resulting in the ability to attain large compression ratio with small quality loss. Also, various models incorporating Human Visual System (HVS) to Discrete Cosine Trans-form (DCT) scheme are considered. Using the exact frequency components of DCT basis function, the optimum modulation transfer function (MTF) is obtained analytically. The errors at a block boundary which is important factor in transform coder are criteria for error measurement. The HVS weight coding results in perceptually higher quality images compared with the unweighted scheme.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.166.3-167
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• 2003

Helenalin, a cell-permeable pseudoguainolide sesquiterpene lactone, is a potent anti-inflammatory agent that inhibits $NF-{\kappa}B$ DNA binding activity by selectively alkylating the p65 subunit of $NF-{\kappa}B$. Transcription factors such as $NF-{\kappa}B$ provide powerful target of drugs to use in the treatment of cancer. Human promyelocytic leukemia HL-60 cells are differentiated into monocytic or granulocytic lineage when treated with 1,25-dihydroxyvitamin $D_3{\;}[1,25-(OH)_2D_3]$ or all-trans-retinoic acid (ATRA), respectively. (omitted)

• Biomolecules & Therapeutics
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• v.11 no.2
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• pp.91-98
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• 2003

A new series of highly water soluble platinum(II) complexes[Pt(II)(DL-2-hydroxy-3-methylbutyrate)(trans-l-1,2-dimninocyc1ohexane)] (PC-1) and [Pt(II)DL-2-hydroxy-3-methylbutyrate](cis-1,2-diaminocyclohexane)](PC-2) were synthesized and characterized by their elemental analysis and by various spectroscopic techniques [infrared(IR), $^{13}C$-nuclear magnetic resonance (NMR)]. In vitro antitumor activity of new Pt(II)complexes was tested against MKN-45, MKN/ADM and MKN/CDDP human gastric adenocarcinoma cell lines using colorimetric MTT[3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazoliumbromide] assay for cell survival and proliferation. PC-1 and PC-2 showed active against MKN-45/P, MKN/ADM and MKN/CDDP human gastric cancer cell lines, and the antitumor activity of these compounds were comparable or superior to that of cisplatin. The nephrotoxicities of PC-1 and PC-2 were found quite less then that of cisplatin using MTT and [$^3H$] thymidine uptake tests in rabbit proximal tubule cells, human kidney cortical cells human renal cortical tissues. Based on these results, these novel platinum(II) complex compounds(PC-1 ＆ PC-2) represent a valuable lead in the development of the new anticancer chemotherapeutic agents capable of improving antitumor activity and low nephrotoxicity.

• Archives of Pharmacal Research
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• v.28 no.5
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• pp.557-560
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• 2005

Resveratrol, a phenolic antioxidant found in grapes, has been known to mediate various biological activities on the human body. In the present study, we tested the antifungal a ctivity of resveratrol against human pathogenic fungi before carrying out further studies to elucidate the antifungal mechanism(s) of resveratrol. Resveratrol displayed potent antifungal activity against human pathogenic fungi at concentration levels of 10-20 ${\mu}g$/mL. Furthermore, time-kill curve exhibited fungicidal effect of resveratrol on C. albicans, but the compound had no hemolytic activity against human erythrocytes. The destruction of C. albicans cells by resveratrol was confirmed by scanning electron microscopy. These results suggest that resveratrol could be employed as a therapeutic agent to treat fungal infections of humans.

• Trans-
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• v.12
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• pp.1-19
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• 2022

This study predicts and raises the changes that AI will bring to dance art when machine-based choreography began, and finds questions we can ask as human artists. Research suggests that one of the crises of dance in the era of machine creative arts is that artificial intelligence does not stay in the tool of human choreography but becomes the subject of choreography. It is based on the political discourse of choreography that artificial intelligence has the power to control and restrict human dancers. This comes from a sense of crisis that the AI takes over the area of choreography and the human choreographer remains an incompetent coordinator, and as a result, the dancer's dancing body can be reduced to a mechanical body controlled by AI. In order for these concerns not to become a reality, this study proposes three measures. First, choreographer and dancer should develop digital literacy to live in the age of AI art. Secondly, choreographer should acquire the ability to accurately distinguish the roles of human choreographer, dancer, and AI in creative work. Thirdly, various levels of discourse on AI dance should be formed by actively conducting mutual media research of dance and technology. Through these efforts, the human dancer will exist as a subject of art, not a passive agent in the new dance ecosystem brought by the innovation of artificial intelligence technology and will be able to face an era coexistence with artificial intelligence creativily and productively.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.237-245
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• 2013

Canthaxanthin (cx) is a potent antioxidant that is chemically synthesized at the industrial scale and has imperative applications in the cosmetic and feed industries. An orange pigmented mesophilic bacterium, designated as K44, was isolated from soil samples of Kargil, India. Biochemical tests, 16S rRNA gene sequencing, and FAME analysis of the bacterium indicated it to belong in the genus Dietzia and is distinct from human isolates. The strain showed 98% 16S rRNA gene sequence homology with Dietzia maris DSM 43102. High-performance liquid chromatography profile of the pigments isolated from K44 showed two major peaks absorbing at 465.3 and 475 nm. The liquid chromatography-mass spectrometry (LC-MS) analysis of both these peaks revealed their m/z to be 564. The molecular weights, LC-MS/MS fragmentation patterns, and ${\lambda}_{max}$ of these fractions corresponded to all-trans- (475 nm) and 9-cis-(465.3 nm) cx isomers. The antioxidant activities of cis- and trans-cx isomers isolated from this bacterium were found to differ, where the cis-isomer showed higher free radical, superoxide radical, and reactive oxygen species scavenging activities than the alltrans- isomer, suggesting that 9-cis-cx is more effective as an antioxidant than the all-trans-cx.

• Korean Journal of Radiology
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• v.22 no.8
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• pp.1352-1368
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• 2021

Objective: For an accurate dynamic contrast-enhanced (DCE) MRI analysis, exact baseline T1 mapping is critical. The purpose of this study was to compare the pharmacokinetic parameters of DCE MRI using synthetic MRI with those using fixed baseline T1 values. Materials and Methods: This retrospective study included 102 patients who underwent both DCE and synthetic brain MRI. Two methods were set for the baseline T1: one using the fixed value and the other using the T1 map from synthetic MRI. The volume transfer constant (K^trans), volume of the vascular plasma space (v_p), and the volume of the extravascular extracellular space (v_e) were compared between the two methods. The interclass correlation coefficients and the Bland-Altman method were used to assess the reliability. Results: In normal-appearing frontal white matter (WM), the mean values of K^trans, v_e, and v_p were significantly higher in the fixed value method than in the T1 map method. In the normal-appearing occipital WM, the mean values of v_e and v_p were significantly higher in the fixed value method. In the putamen and head of the caudate nucleus, the mean values of K^trans, v_e, and v_p were significantly lower in the fixed value method. In addition, the T1 map method showed comparable interobserver agreements with the fixed baseline T1 value method. Conclusion: The T1 map method using synthetic MRI may be useful for reflecting individual differences and reliable measurements in clinical applications of DCE MRI.