• The Korean Journal of Applied Statistics
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• v.35 no.2
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• pp.177-188
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• 2022

The support vector machine (SVM) has been successfully applied to various classification areas with a high level of classification accuracy. However, it is infeasible to use the SVM in analyzing massive data because of its significant computational problems. When analyzing imbalanced data with different class sizes, furthermore, the classification accuracy of SVM in minority class may drop significantly because its classifier could be biased toward the majority class. To overcome such a problem, we propose the DOC-SVM method, which uses divide-oversampling and conquers techniques. The proposed DOC-SVM divides the majority class into a few subsets and applies an oversampling technique to the minority class in order to produce the balanced subsets. And then the DOC-SVM obtains the final classifier by aggregating all SVM classifiers obtained from the balanced subsets. Simulation studies are presented to demonstrate the satisfactory performance of the proposed method.

• The Korea Journal of Herbology
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• v.33 no.1
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• pp.93-93
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• 2018

• Journal of agriculture & life science
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• v.50 no.2
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• pp.139-150
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• 2016

Few studies have been reported that horse-bone extract(HBE) can prevent and treatment of bone diseases. However, HBE' therapeutic activities are still not fully understood. This study determined whether HBE up-regulates hemeoxygenase 1(HO-1) and this mediates its anti-inflammatory effect in murine macrophages.Nitric oxide(NO) assay, MTT assay and DPPH assay were performed. In addition, Western blotting and real time PCR were used to determine protein expression, and gene expression, respectively. HBE significantly inhibited NO production without observable cytotoxicity. In addition, HBE attenuated inducible nitric oxide synthase (iNOS), cyclooxygenase-2(COX-2) and phospho (p)-ERK protein expressions in LPS(0.1㎍/ml) stimulated RAW264.7 cells. On the other hand, HBE alone up-regulated HO-1 and Nrf-2 expressions, which mediated HBE's anti-inflammatory effect in RAW264.7 cells. Finally, HBE up-regulated HO-1 and impaired ERK1/2 signaling pathways, and thus it may provide protection against cellular oxidation and inflammation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.34 no.1
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• pp.136-136
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• 2021

• The Journal of Pediatrics of Korean Medicine
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• v.35 no.4
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• pp.167-167
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• 2021

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.544-552
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• 2021

This study investigated the anti-fibrotic and antioxidant effects of Paeonia Radix Alba water extract (PR) on thioacetamide (TAA)-induced liver fibrosis in a mouse model and its underlying mechanisms. Liver fibrosis was induced by intraperitoneal injection of TAA (three times a week) for 8 weeks. Furthermore, silymarin (50 mg/kg body weight) and PR (200 mg/kg body weight) were administered for 8 weeks. PR treatment downregulated aspartate aminotransferase (AST), alanine aminotransferase (ALT), ammonia, and myeloperoxidase levels. Moreover, PR treatment downregulated NOX2 and p47phox and upregulated antioxidant enzymes by activating the Nrf2/Keap1 signaling pathway. Furthermore, PR inhibited the factors associated with fibrosis, such as α-SMA and collagen I. AMPK/SIRT1 was upregulated by PR treatment. Overall, these results suggest that PR attenuates liver fibrosis by regulating the Nrf2/Keap1 and AMPK/SIRT1/NF-κB signaling pathways through the inhibition of oxidative stress. Hence, PR has potential as a remedy for preventing and treating liver fibrosis.

• Journal of Nutrition and Health
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• v.54 no.4
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• pp.412-421
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• 2021

Purpose: Thioacetamide (TAA) produces reactive oxygen species (ROS) in the liver, and the generated ROS induces liver injury through inflammatory reactions. The current study was undertaken to investigate the hepatoprotective effect of Artemisiae Capillaris Herba water extract (AC), imparted via its antioxidant activity, in an animal model of TAA-induced liver injury. Methods: Animal experiments were conducted in 5 groups: normal, control (TAA 200 mg/kg), SM (TAA 200 mg/kg + silymarin 100 mg/kg), ACL (TAA 200 mg/kg + AC 100 mg/kg), ACH (TAA 200 mg/kg + AC 200mg/kg). TAA (intraperitoneal) and treatment compounds (per oral) were administered for 3 days. Serum levels of ammonia concentration and myeloperoxidase (MPO) activity were subsequently measured. Liver tissues were subjected to western blot analysis for measuring the oxidative stress (NADPH oxidase), anti-oxidative activity (Nrf2, heme oxygenase-1 [HO-1], superoxide dismutase [SOD], catalase, and GPx-1/2), tissue inhibitors of metalloproteinase (TIMP)-1, and matrix metalloproteinases (MMPs) protein expressions. Results: Serum ammonia levels and MPO activity were significantly increased in the TAA-induced control group, whereas groups administered AC treatment showed markedly reduced levels. Western blot analysis revealed significantly increased NOX2 and p22^phox expressions, (oxidative stress-related factors) in the TAA-induced control group. These levels were determined to be significantly decreased after AC exposure. Moreover, antioxidant-related factors including Nrf2, HO-1, SOD, catalase, and GPx-1/2 were significantly decreased in the control group and increased in the AC treated groups. In addition, MMP expressions were significantly suppressed in the AC treatment group due to increased levels of TIMP-1. Conclusion: Taken together, these data indicate that exposure to AC reduces the oxidative stress by inhibiting the expression of NADPH oxidase (NOX2 and p22^phox) through the Nrf2 signaling pathway. We therefore propose the potential of AC for the prevention and treatment of TAA-induced liver injury.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.477-484
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• 2011

When an event of target variable is rare, a widespread strategy is to build a model on the sample that disproportionally over-represents the events, that is over-sampled. Using the data over-sampled from the original data set, the predicted values would be biased; however, it can be easily corrected to represent the population. In this study, we investigate into the relationship between the proportion of rare event on a data-mart and the model performance using real world data of a Korean credit card company. Also, we use the methods for adjusting of posterior probability for over-sampled data of the offset method and the weighted method. Finally, we compare the performance of the methods using real data sets.

• Journal of Life Science
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• v.31 no.10
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• pp.885-897
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• 2021

Schisandrae Fructus (SF) and Corni Fructus (CF) have been used for a long time for the prevention and treatment of various diseases. Although reports have highlighted the possibility of inhibiting the onset and progression of benign prostatic hyperplasia (BPH), studies on related mechanisms are still lacking. In this study, we investigated the potential of SF and CF in improving BPH by using a dihydrotestosterone (DHT)-induced in vitro BPH model using LNCaP prostate carcinoma cells. According to our results, water and ethanol extracts of SF and CF significantly inhibited the proliferation of LNCaP cells by DHT treatment and markedly downregulated the expression of DHT-induced BPH biomarkers and growth factors. They also regulated the expression of apoptosis regulatory factors and significantly reduced DHT-mediated oxidative stress. In addition, the protective effect on major factors involved in the pathogenesis of BPH was more effective in the ethanol extract treatment group than in the water extract group. Furthermore, the improvement effect on BPH was higher in the 1:1 combined treatment group than in the ethanol extract alone treatment group of SF and CF, and 60% ethanol extracts showed a better effect than 40% ethanol extracts. Therefore, our findings demonstrate that SF and CF can protect against BPH by preventing the hyperproliferation of prostate cells through the inhibition of the androgen signaling pathway, which was correlated with their antioxidant activities. Therefore, SF and CF extracts may be useful in the clinical treatment of BPH, and the combination of these two extracts can be synergistic.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.83-83
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• 2020

염증은 물리화학적 자극이나 세균 감염과 같은 외부 자극에 대응하기 위한 생체조직의 방어 반응의 하 나이며 조직이나 장기의 손상을 회복시키는 기전으로서 매우 중요한 역할을 하지만 염증반응이 과도해 질 경우 궤양성 대장염, 기관지염, 천식, 대장암 등을 유발하는 원인으로 작용하기 때문에 염증반응을 조 절하는 항염증제 개발은 매우 중요시되고 있다. 국내 염증개선 관련 시장은 현재 약 3조원 규모이며 지속 적인 성장세에 있지만 천연소재의 기능성 중심으로 출시된 제품 중 다수의 제품에서 주로 수입 원료를 사용하고 있어 국내 자생 및 재배하는 천연 소재들의 효능에 대한 검증을 통해 수입 원료 의존도를 낮추 기 위한 연구가 요구되고 있다. 따라서 본 연구에서는 순창에서 재배되는 참두릅 (Aralia elata Seem)과 도라지 (Platycodon grandiflorum)를 이용하여 천연 염증개선 소재화를 목적으로 기능성 증진을 위한 추 출조건 선정과정과 대식세포에 대한 세포독성 및 항염증 효능을 확인하여 천연소재를 이용한 염증개선 소재화를 시도하고자 한다. 본 연구는 전북 순창에서 재배되는 참두릅과 도라지의 추출조건을 선정하기 위해 용매, 온도 및 시간별 추출물의 total polyphenol 함량 평가를 통하여 최적 추출조건 선정을 진행하 였으며, 선정된 추출조건에서 추출된 추출물의 항산화 활성을 측정하기 위하여 DPPH & ABTS radical scavenging activity 및 total flavonoids 함량을 확인하여 항산화 효능을 평가하였다. 또한 대식세포인 Raw 264.7을 사용하여 MTT assay, Nitric oxide (NO) 생성 억제 효능을 확인하여 세포독성 및 항염증 활 성을 평가하였다. 실험결과, Total polyphenol 함량 분석을 통해 최적 추출조건이 선정된 두릅 (주정 40%, 25℃, 3 h), 도라지 (주정 60%, 25℃, 1 h)의 추출물을 이용하여 DPPH & ABTS radical scavenging activity 및 total flavonoids 함량을 분석한 결과, 도라지보다 두릅에서 더 높은 항산화 활성을 나타내었다. 대식세포를 활용한 두릅과 도라지의 세포독성을 측정한 결과, 100 ug/mL 이내의 농도에서 독성활성이 나타내지 않음을 확인되었으며, 항염증 활성을 측정한 결과 100 ug/mL에서 두릅 추출물이 도라지 추출 물보다 약 33% 이상 NO 생성억제 활성이 높게 나타내었다.