• Journal of Korea Game Society
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• v.16 no.4
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• pp.79-86
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• 2016

Monte-Carlo Tree Search(MCTS) is a best-first tree search algorithm and has been successfully applied to various games, especially to the game of Go. We evaluate the performance of MCTS playing against each other in the game of Tic-Tac-Toe. It reveals that the first player always has an overwhelming advantage to the second player; and we try to find out the reason why the first player is superior to the second player in spite of the fact that the best game result should be a draw. Since MCTS is a statistical algorithm based on the repeated random sampling, it cannot adequately tackle an urgent problem that needs a strategy, especially for the second player. For this, we propose a strategic MCTS(S-MCTS) and show that the S-MCTS player never loses a Tic-Tac-Toe game.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.49 no.2
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• pp.115-122
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• 2012

We present here a new class of activation functions for neural networks, which herein will be called CosGauss function. This function is a cosine-modulated gaussian function. In contrast to the sigmoidal-, hyperbolic tangent- and gaussian activation functions, more ridges can be obtained by the CosGauss function. It will be proven that this function can be used to aproximate polynomials and step functions. The CosGauss function was tested with a Cascade-Correlation-Network of the multilayer structure on the Tic-Tac-Toe game and iris plants problems, and results are compared with those obtained with other activation functions.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.246-256
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• 2017

Purpose: This study aimed to investigate the association of total dietary antioxidant capacity (TAC) with oxidative stress and metabolic markers among patients with metabolic syndrome according to gender. Methods: A total of 346 subjects aged 30~59 years with two or more risk factors of metabolic syndrome were recruited from a general hospital near Seoul in South Korea between 2010 and 2012 based on data from the medical checkup. Biochemical indices for oxidative stress and metabolic markers were measured. Food consumption data from 3-day food records were linked with the antioxidant capacity database for commonly consumed Korean foods to estimate individual's TAC. Results: Average dietary TAC of the study subjects was 132.0 mg VCE/d/1,000 kcal in men and 196.4 mg VCE/d/1,000 kcal in women. Levels of ${\gamma}$-glutamyltransferase (GGT), systolic blood pressure, diastolic blood pressure, and blood triglycerides were reduced significantly according to increasing TAC in men, but there was no significant trend in women. Intakes of total flavonoids and carotenoids were significantly negatively correlated with GGT (p < 0.05) and d-ROMs (p < 0.01) in men, whereas those of ${\alpha}$-tocopherol (p < 0.05) and ${\gamma}$-tocopherol (p < 0.05) were positively correlated with biological antioxidant potential (BAP) in women. The odds ratio of high oxidative stress indices and abnormal metabolic markers according to TAC level were not significant in either men or women. Conclusion: The results show that dietary TAC was partially associated with oxidative stress and metabolic markers among patients with metabolic syndrome. Further research is required for elucidating the association between dietary TAC and incidence of metabolic syndrome and chronic diseases within a large population in prospective studies.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.4
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• pp.235-240
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• 2010

Toll-like receptors (TLRs) functionally expressed in salivary epithelial cells, but their roles remain elusive. Among TLRs family, TLR3 is activated by dsRNA, a byproduct of viral infection. The aim of this study was to investigate the role of TLR3 in the inflammatory immune responses using HSG cells. Reverse transcriptase-polymerase chain reaction (RT-PCR), real-time PCR and ELISA were performed to identify expression of TLRs and TLR3-mediated chemokine inductions. The chemotaxis assay of activated T lymphocytes was also performed. Treatment of HSG cells with polyinosinic: polycytidylic acid (poly(I:C)) significantly increased interferon-$\gamma$-inducible protein 10 (IP-10), interferoninducible T-cell $\alpha$ chemoattractant (I-TAC), and regulated on activation, normal T-cells expressed and secreted (RANTES) gene expressions in a concentration-dependent manner. Anti-TLR3 antibody blocked the increases of IP-10 and I-TAC genes. Poly(I:C)-induced increases of IP-10 and I-TAC were also confirmed at protein levels from cell lysates, but their release into extracellular medium was detected only in IP-10. We found that the culture media from HSG cells stimulated with poly(I:C) significantly increases T lymphocyte migration. Our results suggest that TLR3 plays an important role in chemokine induction, particularly IP-10, in salivary epithelial cells.

• The Journal of Korean Medicine
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• v.32 no.6
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• pp.41-53
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• 2011

Objectives: This study was performed to investigate the effect of Jaeumgeonbigagamtang (JGT) onrestraint-induced oxidative stress in the mouse brain. Methods: After treatment with JGT, CBC, ROS, MDA, TAC, SOD, activity of catalase, and total GSH content were analyzed. Results: JGT had a strong antioxidant activity by in vitro assay as presented GEAC. JGT treatment significantly ameliorated decrease of blood WBC and increase of platelet count. JGT (50mg/kg) treatment significantly ameliorated increase of MDA and GSH content level in brain tissue. JGT (100mg/kg) treatment significantly ameliorated increase of MDA and activity of TAC level in brain tissue. JGT (200mg/kg) treatment significantly ameliorated increase of ROS, MDA, activity of TAC level and depletion of catalase level in brain tissue. Conclusion: The present study demonstrated antioxidant activity in brain tissue. This result would be consistent with the long clinical efficacy of JGT, and this finding may provide a strong possibility of JGT as a drug candidate for brain-specific multiple disorders and symptoms.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5343-5348
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• 2015

Promoter hypermethylation of the runt-related transcription factor 3 (RUNX3) gene is associated with increased risk of hepatocellular carcinoma (HCC). Oxidative stress plays a vital role in both carcinogenesis and progression of HCC. However, whether oxidative stress and RUNX3 hypermethylation in HCC have a cause-and-effect relationship is not known. In this study, plasma protein carbonyl and total antioxidant capacity (TAC) in patients with hepatitis B virus (HBV)-associated HCC (n=60) and age-matched healthy subjects (n=80) was determined. RUNX3 methylation in peripheral blood mononuclear cells (PBMC) of subjects was measured by methylation-specific PCR. Effect of reactive oxygen species (ROS) on induction of RUNX3 hypermethylation in HCC cells was investigated. Plasma protein carbonyl content was significantly higher, whereas plasma TAC was significantly lower, in HCC patients than healthy controls. Based on logistic regression, increased plasma protein carbonyl and decreased plasma TAC were independently associated with increased risk for HCC. PBMC RUNX3 methylation in the patient group was significantly greater than in the healthy group. RUNX3 methylation in hydrogen peroxide ($H_2O_2$)-treated HepG2 cells was significantly higher than in untreated control cells. In conclusion, increase in oxidative stress in Thai patients with HBV-associated HCC was demonstrated. This oxidative increment was independently associated with an increased risk for HCC development. RUNX3 in PBMC was found to be hypermethylated in the HCC patients. In vitro, RUNX3 hypermethylation was experimentally induced by $H_2O_2$. Our findings suggest that oxidative stress is a cause of RUNX3 promoter hypermethylation in HCC cells.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.334-337
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• 2008

A tightly regulated gene expression system composed of a single-copy target gene under the control of a lac promoter derivative and lacI gene in a multicopy plasmid is proposed, and its ability to control the flux of a metabolic pathway is demonstrated. A model system to control the flux of acetyl-CoA to acetyl phosphate was constructed by integrating pta, a gene encoding phosphotransacetylase, under a tac promoter into the chromosome of E. coli with a pta-negative background and transforming a multicopy plasmid containing the $lacI^Q$ gene into the strain. The production rate of acetate was shown to be tightly controlled when varying the concentration of the inducer (IPTG) in he model system.

• The Korean Journal of Nuclear Medicine
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• v.20 no.2
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• pp.53-59
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• 1986

Radionuclide angiography of the liver and spleen with rapid bolus injection of 5 mCi of $^{99m}Tc-Sn-phytate$ was performed for evaluation of dynamic flow change of the liver in 5 normal subjects and 11 patients with diffuse hepatocellular diseases. And quantification of hepatic arterial index (HAI) was generated from those TACs of the liver and compared with HAI generated from hepatic TAC with injection of $^{99m}Tc-TcO_4^-$ as previously reported method by former investigators, 67 patients with diffuse hepatocellular diseases undergoing hepatic scintigraphy were also evaluated by 2 minutes-hepatosplenic scintiangiography with 5 mCi of $^{99m}Tc-phytate$ and followed injection of 7 mCi of $^{99m}Tc-TcO_4^-$. Those heaptic and splenic TACs were analysed and compared with HAIs of 99m Tc-phytate for evaluation of relative change (%) of count at 30 seconds and 1 minuite after peaks of rapid influx phase to the peaks (100%) in T ACs of $^{99m}Tc-phytate$ and at 1 minuite and 3 minuites after in 5 minuite-TAC of $^{99m}Tc-TcO_4^-$. Correlation between HAIs with $^{99m}Tc-phytate$ and $^{99m}Tc-TcO_4^-$ was highly significant (R=0,984, P=0), and there was most significant and useful correlation (R=0,708, p<0.0001) between HAI and splenic TAC generated by $^{99m}Tc-phytate$.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.61-72
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• 1995

The author performed radionuclide esophageal transit studies(RETS) with liquid and solid boluses using the same day protocol in 90 normal controls and 164 patients with various primary esophageal motility disorders who were diagnosed by manometric criteria and clinical courses. The authors calculated mean esophageal transit time(MTT) and mean residual retention(MRR) in each of the liquid and solid studies, and classified time-activity curve(TAC) patterns. The normal criteria of RETS with liquid bolus were MTT<24 sec, MRR<9%, and the TAC pattern that showed rapid declining slope and flat low residual(Type 1). The normal criteria of RETS with solid bolus were MTT<35 sec, MRR<9% and TAC of type 1. With these normal criteria, the sensitivity and the specificity of the liquid study were 62.2 % and 97.8%, respectively. The sensitivity increased to 75.4% with the solid study. The author also found that the RETS was highly reproducible. The achalasia typically showed no effective emptying of both liquid and solid boluses during the whole study period, and was well differentiated by its extremely long transit time and high retention from the other motility disorders. The diffuse esophageal spasm (DES) and nonspecific esophageal motility disorder(NEMD) showed intermediate delay in transit time and increased retention. In the groups of hypertensive lower esophageal sphincter(LES), hypotensive LES and nutcracker, there noted no significant difference with the normal control group in terms of MTT and MRR. The DES and NEMD could be more easily identified by solid studies that showed more marked delay in MTT and increased MRR as compared with the liquid study. In conclusion, esophageal scintigraphy is a safe, noninvasive and physiologic method for the evaluation of esophageal emptying.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.1
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• pp.54-60
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• 2020

Objective: Oxidative stress plays a key role in the pathogenesis of male infertility. But, the adverse effects of oxidative biomarkers on sperm quality remain unclear. This study aimed to investigate the levels of nitric oxide (NO), 8-hydroxydesoxyguanosine (8-OHdG), and total antioxidant capacity (TAC) oxidative biomarkers in seminal plasma and their relationship with sperm parameters. Methods: A total of 77 volunteers participated in the study, including fertile (n = 40) and infertile men (n = 37). NO, 8-OHdG, and TAC levels were measured using the ferric reducing ability of plasma, Griess reagent method and an enzyme-linked immunosorbent assay kit, respectively. Results: The mean values of sperm parameters in the infertile group were significantly lower than those in the fertile group (p< 0.001). The mean 8-OHdG in the seminal plasma of infertile men was significantly higher (p= 0.013) than those of controls, while the mean TAC was significantly lower (p= 0.046). There was no significant difference in NO level between the two groups. The elevated seminal 8-OHdG levels were negatively correlated with semen volume, total sperm counts and morphology (p< 0.001, p= 0.001 and p= 0.052, respectively). NO levels were negatively correlated with semen volume, total sperm counts and morphology (p= 0.014, p= 0.020 and p= 0.060, respectively). Positive correlations between TAC and both sperm count and morphology (p= 0.043 and p= 0.025, respectively) were also found. Conclusion: These results suggested that increased levels of NO and 8-OHdG in seminal plasma could have a negative effect on sperm function by inducing damage to the sperm DNA hence their fertility potentials. Therefore, these biomarkers can be useful in the diagnosis and treatment of male infertility.