• Environmental Analysis Health and Toxicology
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• v.21 no.3 s.54
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• pp.275-282
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• 2006

In order to get insight into the mechanism of cadmium (Cd)-induced brain injury, we investigated the effects of Cd on the induction of COX-2 in bEnd.3 mouse brain endothelial cells. Cd induced COX-2 expression and $PGE_2$ release, which were attenuated by thiol-reducing antioxidant N-acetylcysteine (NAC) indicating oxidative components might contribute to these events. Indeed, Cd increased cellular reactive oxygen species (ROS) level and DNA binding activity of nuclear factor-kB (NF-kB), an oxidative stress sensitive transcription factor. Cd-induced $PGE_2$ production and COX-2 expression were significantly attenuated by Bay 11 7082, a specific inhibitor of NF-kB and by SB203580, a specific inhibitor of p38 mitogen activated protein kinase (MAPK). These data suggest that Cd induces COX-2 expression through activation of NF-kB and p38 MAPK, the oxidative stress-sensitive signaling molecules, in brain endothelial cells.

• Genomics & Informatics
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• v.20 no.2
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• pp.23.1-23.9
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• 2022

A survival prediction model has recently been developed to evaluate the prognosis of resected nonmetastatic pancreatic ductal adenocarcinoma based on a Cox model using two nationwide databases: Surveillance, Epidemiology and End Results (SEER) and Korea Tumor Registry System-Biliary Pancreas (KOTUS-BP). In this study, we applied two machine learning methods-random survival forests (RSF) and support vector machines (SVM)-for survival analysis and compared their prediction performance using the SEER and KOTUS-BP datasets. Three schemes were used for model development and evaluation. First, we utilized data from SEER for model development and used data from KOTUS-BP for external evaluation. Second, these two datasets were swapped by taking data from KOTUS-BP for model development and data from SEER for external evaluation. Finally, we mixed these two datasets half and half and utilized the mixed datasets for model development and validation. We used 9,624 patients from SEER and 3,281 patients from KOTUS-BP to construct a prediction model with seven covariates: age, sex, histologic differentiation, adjuvant treatment, resection margin status, and the American Joint Committee on Cancer 8th edition T-stage and N-stage. Comparing the three schemes, the performance of the Cox model, RSF, and SVM was better when using the mixed datasets than when using the unmixed datasets. When using the mixed datasets, the C-index, 1-year, 2-year, and 3-year time-dependent areas under the curve for the Cox model were 0.644, 0.698, 0.680, and 0.687, respectively. The Cox model performed slightly better than RSF and SVM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1109-1113
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• 2008

The purpose of this study was to investigate the antioxidative and antiallergic effects of aronia extract. The aronia extract was tested for various antioxidative potentials (scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical) and inhibitory effect of 5-lipoxygenase (5-LO) and cyclooxygenase (COX). In aronia extract, polyphenol content was $81.6{\pm}3.3\;mg/g$ and flavonoid content was $5.15{\pm}0.16\;mg/g$. DPPH radical-scavenging activity ($SC_{50}$) of aronia extract was $6.15{\pm}0.343\;ppm$. $SC_{50}$ value of aronia extract against superoxide anion radical was $6.99{\pm}1.28\;ppm$. In addition, $IC\_{50}$ values of aronia extract against 5-LO, COX-1, and COX-2 were $42.07{\pm}0.15\;ppm$, $24{\pm}4.29\;ppm$, and $24.3{\pm}3.5\;ppm$, respectively. These results suggest that aronia extract may be useful for the prevention or treatment of allergic disease.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05b
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• pp.88.2-98
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• 2002

A wide arry of naturally occurring substances particularly those present in dietary and medicinal plants, have been reported to possess substantial cancer chemopreventive properties. Certain phytochemicals retain strong antioxidative and anti-inflammatory properties which appear to contribute to their chemopreventive or chemoprotective activities. Inducible cyclooxygenase(COX-2) and nitric oxide synthase (iNOS) are important enzymes that mediate inflammatory processes. There is some evidence that expression of both COX-2 and iNOS is co-regulated by the eukaryotic transcription factor NF-$textsc{k}$B. Increased expression of COX-2 and/or iNOS has been associated with pathophysiology of certain types of human cancers as well as inflammatory diseases. Since inflammation is closely linked to tumor promotion, substances with potent anti-inflammatory activies are anticipated to exert chemopreventive effects on carcinogenesis, particularly in the promotion stage. An example is curcumin, a yellow pigment of turmeric (Curcuma longa L., Zingiberaceae), that strongly occurring diaryl heptanoids structurally related to curcumin have substantial anti-tumor promotional activities in two-stage mouse skin carcinogenesis. Thus, yakuchinone A [1-(4'-hydroxy-3'-methoxyphenyl)-7-phenyl-3heptanone] and yakuchinone B [1-(4'-hydroxy-3'methoxyphenyl)-7-phenylhept-1-en-3-one] present in Alpinia oxyphylla Miquel (Zingiberacease) attenuate phorbol ester-induced inflammation and papilloma formation in female ICR mice. These diarylheptanoids also suppressed phorbol ester-induced activation of epdermal ornithine decarboxylase and its mRNA expression when applied onto shaven backs of mice. Yakuchinone A and B as well as curcumin inhibited phorbol ester-induced expression of COX-2 and iNOS and their mRNA in mouse skin via inactivation of NF-$textsc{k}$B. Capsaicin, a major pungent ingredient of red pepper also attenuated phorbol ester-induced NF-$textsc{k}$B activation. Similar suppression of COX-2 and iNOS and down-regulation of NF-$textsc{k}$B activation for its DNA binding were observed with the ginsenosied Rg3 and the ethanol extract of Artemisia asiatica. We have also found that certain anti-inflammatory phytochemicals exert inhibitory effects on phorbol ester-induced COX-2 expression and NF-$textsc{k}$B activation in immortalized human breast epithelial (MCF-10A) cells in culture. One of the plausible mechanisms undelying inhibition by aforementioned phytochemicals of phorbol ester-induced NF-$textsc{k}$B activation involves interference with degragation of the inhibitory unit, I$textsc{k}$Ba, which blocks subsequent nuclear translocation of the functionally active p65 subunit of NF-$textsc{k}$B. the activation of epidermal NF-$textsc{k}$B by phorbol ester and subsequent induction of COX-2 hence appear to play an important role in intracellular signaling pathwasy leading to tumor promotion and targeted inhibition of NF-$textsc{k}$B may provide a new promising cancer chemopreventive strategy.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.332-336
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• 2008

Ginger is widely used as a traditional herbal medicine. Both ginger and its extracts have been used to treat many chronic inflammatory conditions via the inhibition of nuclear factor-kappa B (NF-${\kappa}B$) activation, which results in the suppression of cyclooxygenase-2 (COX-2) expression. However, the mechanisms as to how ginger extracts mediate their health effects are largely unknown. Toll-like receptors (TLRs) trigger anti-microbial innate immune responses, recognizing conserved microbial structural molecules that are known as pathogen-associated molecular patterns. All TLR signaling pathways culminate in the activation of NF-${\kappa}B$. The activation of NF- ${\kappa}B$ leads to the induction of inflammatory gene products, including cytokines and COX-2. This study reports the biochemical evidence that 6-shogaol, an active compound in ginger, inhibits NF-${\kappa}B$ activation and COX-2 expression induced by TLR2, TLR3, and TLR4 agonists. Furthermore, 6-shogaol inhibited NF-${\kappa}B$ activation induced by the following downstream signaling components of the TLRs: MyD88, $IKK{\beta}$, and p65. These results imply that ginger can modulate immune responses that could potentially modify the risk of many chronic inflammatory diseases.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.95-103
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• 2008

In the present study, we investigated the anti-inflammatory effects by kaempferol-3-O-${\beta}$-D-sophoroside (KS) isolated from Sophora japonica (Leguminosae) on the lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin ($PGE_2$) production by RAW 264.7 cell line compared with kaempferol. KS significantly inhibited the LPS-induced NO and $PGE_2$ production. Consistent with these observations, KS reduced the LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in a concentration-dependent manner. In addition, the release and the mRNA expression levels of tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and interleukin-6 (IL-6) were also reduced by KS. Moreover, KS attenuated the LPS-induced activation of nuclear factor-kappa B ($NF{-\kappa}B$), a transcription factor necessary for pro-inflammatory mediators, iNOS, COX-2, $TNF-{\alpha}$ and IL-6 expression. These results suggest that the down regulation of iNOS, COX-2, $TNF-{\alpha}$, and IL-6 expression by KS are achieved by the downregulation of $NF{-\kappa}B$ activity, and that is also responsible for its anti-inflammatory effects.

• Journal of Chest Surgery
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• v.44 no.1
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• pp.18-24
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• 2011

Background: We evaluated the efficacy of Cox-maze IV procedure using bipolar irrigated radiofrequency ablation and cryothermy in chronic atrial fibrillation associated with valvular heart disease. Material and Methods: From November 2005 to June 2009, ninety four patients have undergone valvular heart surgery with Cox-maze IV procedure. Preoperative duration of atrial fibrillation was $7.6{\pm}6.5$ years and follow-up duration was $22.7{\pm}12.3$ months. Results: There were two (2.1%) postoperative deaths not related to maze procedure. Two cerebrovascular accidents, five low cardiac output syndromes and two permanent pacemaker implantations have occurred after surgery. Preoperative ejection fraction on echocardiography was $55.3{\pm}8.1%$ and ejection fraction of postoperative six month was $54.7{\pm}6.5%$. Left atrial size of preoperative and postoperative were $61.5{\pm}11.6\;mm$ and $53.1{\pm}8.4\;mm$ at each. Freedom from atrial fibrillation rate at postoperative six-month was 80.7% and the cases of recurrence of atrial fibrillation after six months were three (3.3%). Risk factors for failure or recurrence of maze procedure were old age (p=.010) and preoperative moderate or severe tricuspid regurgitation (p=.033). Conclusion: The Cox-maze IV procedure using RFBP2 and cryothermy is quite safe and freedom from atrial fibrillation at postoperative 6 month was 82.5%. Risk factors for failure or recurrence of atrial fibrillation after Cox-maze IV were old age and preoperative over moderate tricuspid regurgitation.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.15 no.1
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• pp.91-100
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• 2004

Objectives：The effects of repeated maternal separation on the expression of glucocorticoid receptor (GR) and cyclooxygenase-2(COX-2) in the hippocampus of rat pups at preweanling stage were evaluated. Methods：The experimental, Repeated Maternal Separation group(N=4) was separated from the mother for four hours a day over a period of ten days beginning with postnatal day 4. The Control group(N=4), on the other hand, did not separated from the mother at all. GR and COX-2 expression in the hippocampus was examined by immunohistochemistry on postnatal day 14. Results：It was determined that the number of GR-immunopositive cells in the dentate gyrus of the hippocampus was significantly increased in the Repeated Maternal Separation group. The numbers of COX-2-immunopositive cells in the CA1 and CA3 were also significantly higher in the Repeated Maternal Separation group. Conclusion：These results suggest that maternal separation may be a significant developmental stress that induces GR and COX-2 expression in the hippocampus of developing pups.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.571-576
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• 2016

In this study, the anti-inflammatory activities of the 80% ethanol extract of Dystaenia takeshimana (DT) were investigated using Raw 264.7 cells treated with lipopolysaccharide (LPS). The effect of DT extract on the production of pro-inflammatory factors (iNOS, COX-2) in LPS-stimulated Raw 264.7 macrophages was examined. The cytotoxic effect of DT extract on macrophage cells (Raw 264.7) was examined by the 3-[4, 5-dimethyl-thiazol-2-yl]-2, 5-diphenyl-tetrazoliumbromide (MTT) assay. Treatment with DT extract showed 100% or more cell viability at the concentration $1,000{\mu}g/ml$. The inhibitory effect of DT extract on protein expression of inducible NOS (iNOS) and cyclooxygenase-2 (COX-2) was measured by western blotting using the concentrations 50, 100, and $500{\mu}g/ml$, with ${\beta}-actin$ used as the positive control. Consequently, the protein expression of iNOS, and COX-2 as observed by western blotting, was decreased by 56%, 61.6%, respectively with $500{\mu}g/ml$ DT extract. Inhibition of iNOS and COX-2 mRNA expression was measured by reverse transcription- polymerase chain reaction (PCR) using DT extract concentrations 50, 100, and $500{\mu}g/ml$, with GAPDH used as a positive control. Consequently, the mRNA expression of iNOS and COX-2 as observed by reverse-transcription-PCR was decreased by 77.9% and 83.3%, respectively at $500{\mu}g/ml$ concentration of DT extract. In conclusion, DT extract may affect inflammatory factors as a potential anti-inflammatory agent.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.789-800
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• 2008

Current credit evaluation models based on financial data make use of smoothing estimated default ratios which are transformed from each financial variable. In this work, some problems of the credit evaluation models developed by financial experts are discussed and we propose improved credit evaluation models based on the stepwise variable selection method and Box-Cox transformed data whose distribution is much skewed to the right. After comparing goodness-of-fit tests of these models, the validation of the credit evaluation models using statistical methods such as the stepwise variable selection method and Box-Cox transformation function is explained.