Efficacy of Vitamin C Supplements in Prevention of Cancer: A Meta-Analysis of Randomized Controlled Trials

Bobae Lee,Seung-Won Oh,Seung-Kwon Myung 대한가정의학회 2015 Korean Journal of Family Medicine Vol.36 No.6

Background: Previous randomized controlled trials (RCTs) have reported inconsistent findings regarding the association between vitamin C supplementation and the risk of cancer. Methods: We performed a meta-analysis of RCTs to investigate the efficacy of vitamin C supplements for prevention of cancer. We searched the PubMed, EMBASE, and Cochrane Library databases in November 2014 using common keywords related to vitamin C supplements and cancer. Results: Among 785 articles, a total of seven trials were identified, which included 62,619 participants; 31,326 and 31,293 were randomized to vitamin C supplementation and control or placebo groups, respectively, which were included in the final analysis. A fixed-effects meta-analysis of all seven RCTs revealed no significant association between vitamin C supplementation and cancer (relative risk, 1.00; 95% confidence intervals, 0.95–1.05). Similarly, subgroup meta-analysis by dose of vitamin C administered singly or in combination with other supplements, follow- up period, methodological quality, cancer mortality, gender, smoking status, country, and type of cancer also showed no efficacy of vitamin C supplementation for cancer prevention. Conclusion: This meta-analysis shows that there is no evidence to support the use of vitamin C supplements for prevention of cancer.

Roles of His101 in DNA-Binding Domain of Human Heat Shock Factor 1 under Acid pH Environment

Ming Lu,Bobae Kwon,Ziwei Chang,Hyeon-Gyeong Park,박장수 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

평창 발견 석조보살좌상의 보존처리와 3차원 디지털기술을 활용한 복원

조성연,권윤미,최보배 국립중앙박물관 2018 박물관보존과학 Vol.20 No.-

석조보살좌상(신수5971)은 1974년 강원도 평창군에서 발견되었다. 2002년 국립춘천박물관이 개관하면서 옮겨진 보살상은 파손 부위가 넓어 복원이 쉽지 않았다. 본 논문에서는 3D스캐닝과 3D프린팅 기술을 활용하여 전체적인 형태와 손상정도를 파악하여 정확한 형태 복원이 불가능한 결실부를 복원하였다. 표면 장식에 사용된 안료의 종류를 파악하기 위하여 광학 현미경으로 관찰하고 이동형 X-선 형광분석기(p-XRF, Potable X-ray Fluorescence Analyzer)로 주성분을 분석한 후 보존처리하였다. 보존처리는 천연 접착제인 아교를 사용하여 열화된 옻칠을 안정시키고 석재강화제(OH-100)를 사용하여 강화하였다. 조사 결과 불석[(沸石), 제올라이트(Zeolite)] 표면 위에 옻칠을 바르고 그 위에 금을 올리는 도금 기법과 흰색의 안료는 연백(鉛白), 적색의 안료는 연단(鉛丹)과 주사(朱砂)로 확인되었다. 3D 기술을 이용한 역설계 방법으로 복원된 결실부는 잔존 편을 대칭시켜 만들었기 때문에 남아있는 보살상의 형태와 유사하게 제작할 수 있었다. 그러나 출력물은 보살상 파손 부위가 굴곡져 있어 이격 없이 삽입하기 어려우며 출력물의 접합부 수정·보완 작업이 필요하였다. 또한 현재까지 3D 프린팅 재료의 물성연구가 부족하여 자료 수집에 어려움이 있었다. 이러한 문제점들은 향후 좀 더 연구해야할 과제이다. A stone seated bodhisattva (Sinsu5971) was discovered in Pyeongchang-gun, Gangwon-do in 1974 and was transferred to the Chuncheon National Museum upon its opening in 2002. The statue had damage to wide areas and was thus difficult to restore. This study utilized 3D scanning and 3D printing technologies to identify the overall form of the statue and the degree of damage, which allowed the restoration of lost portions that otherwise could not have been accurately restored to their original shape. Prior to the conservation treatment, the pigments used to decorate the surface were investigated using an optical microscope, and their main components were analyzed with a p-XRF (Potable X-ray Fluorescence Analyzer). The deteriorated lacquered surface was stabilized using animal glue and consolidated with stone strengthener (OH-100). The investigation found that the surface of the statue was made of zeolite that was lacquered and then gilded. As for pigments, white lead was used for the white color and red lead and cinnabar were used for red. The lost portions were redesigned by mirroring the remaining parts with 3D technologies. However, it was difficult to affix the 3D printing outputs to the statue without visible gaps since the damaged parts suffered flection. The portions of the outputs to be connected to the statue were thus modified and supplemented. It was also difficult to collect data on the properties of 3D printing materials due to the lack of previous in-depth study. These obstacles are subjects for further study.

Roles of His₁₀₁ in DNA-Binding Domain of Human Heat Shock Factor 1 Under Acid pH Environment

Lu, Ming,Kwon, Bobae,Chang, Ziwei,Park, Hyeon-Gyeong,Park, Jang-Su Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

최소 비용할당 기반 온라인 지게차 운영 알고리즘

권보배,손정열,하병현,kwon, BoBae,Son, Jung-Ryoul,Ha, Byung-Hyun 한국시뮬레이션학회 2018 한국시뮬레이션학회 논문지 Vol.27 No.2

조선소의 지게차는 작업 특성상 무거운 물건을 상/하차하거나 이송하는 작업이 빈번하다. 작업은 동적이며 시간대별로 생성 비율이 다르다. 특히 오전과 오후 업무시간 직후에 작업 발생 비율이 높은 경향을 보인다. 이러한 상/하차 작업과 이송작업의 무게는 매번 다르며, 활용되는 지게차 역시 작업 가능한 허용무게의 제약이 있다. 본 연구에서는 지게차의 원활한 운영을 위해 최소 비용할당을 사용한 최근린 배차 규칙 알고리즘을 제안한다. 제시된 알고리즘은 다양한 종류의 지게차와 다수의 작업을 동시에 고려하여 배차를 결정하며, 지게차 종류에 따른 작업 불가능을 고려하기 위해 가상 지게차와 가상 작업을 생성하는 방법을 제안한다. 그리고 차량의 상태를 고려하여 체계적으로 지게차를 선택하는 방법도 함께 제시한다. 성능지표는 평균 공차이동거리와 평균 작업대기시간으로 한다. 성능비교를 위해 조선소의 지게차 운영방식을 모델링한 우선순위 규칙을 비교 대상으로 한다. 시뮬레이션을 통해 제시한 알고리즘의 우수성을 확인한다. Forklifts in a shipyard lift and transport heavy objects. Tasks occur dynamically and the rate of the task occurrence changes over time. Especially, the rate of the task occurrence is high immediately after morning and afternoon business hours. The weight of objects varies according to task characteristic, and a forklift also has the workable or allowable weight limit. In this study, we propose an online forklift dispatching algorithm based on nearest-neighbor dispatching rule using minimal cost assignment approach in order to attain the efficient operations. The proposed algorithm considers various types of forklift and multiple jobs at the same time to determine the dispatch plan. We generate dummy forklifts and dummy tasks to handle unbalance in the numbers of forklifts and tasks by taking their capacity limits and weights. In addition, a method of systematic forklift selection is also devised considering the condition of the forklift. The performance indicator is the total travel distance and the average task waiting time. We validate our approach against the priority rule-based method of the previous study by discrete-event simulation.

Tumor size measured by preoperative ultrasonography and postoperative pathologic examination in papillary thyroid carcinoma: relative differences according to size, calcification and coexisting thyroiditis

Yoon, Young Hoon,Kwon, Ki Ryun,Kwak, Seo Young,Ryu, Kyeung A.,Choi, Bobae,Kim, Jin-Man,Koo, Bon Seok Springer-Verlag 2014 European archives of oto-rhino-laryngology Vol.271 No.5

Characterization of the Effects of Silver Nanoparticles on Liver Cell Using HR-MAS NMR Spectroscopy

Siwon Kim,현진원,Jinhee Choi,Bobae Kwon,Sangmi Lee,Sosun Kim,김석만 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.6

AgNPs (silver nanoparticles) has been widely used for the commercial products, which have antimicrobial agent, medical devices, food industry and cosmetics. Despite, AgNPs have been reported as toxic to the mammalian cell, lung, liver, brain and other organs and many researchers have investigated the toxicity of AgNPs. In this study, we investigated toxicity of the AgNPs to the liver cell using metabolomics based on HRMAS NMR (High Resolution Magic Angle Spinning Nuclear Magnetic Resonance) technics, which could apply to the intact tissues or cells, to avoid the sample destruction. Target profiling and multivariative statistical analysis were performed to analyze the 1D ^1H spectrum. The results show that the concentrations of many metabolites were affected by the AgNPs in the liver cell. The concentrations of glutathione (GSH), lactate,taurine, and glycine were decreased and most of amino acids, choline analogues, and pyruvate were increased by the AgNPs. Moreover, the levels of the metabolites were recovered upto similar level of metabolites in the normal cell by the pre-treatment of NAC, external antioxidant. The results suggest that the depletion of the GSH by the AgNPs might induce the conversion of lactate and taurine to the pyruvate.

Intraoperative abortion of adult living donor liver transplantation

Jungchan Park,Gyu-Seong Choi,Mi Sook Gwak,Justin Sangwook Ko,Sangbin Han,Bobae Han,Jae Won Joh,Sung Joo Kim,Suk-Koo Lee,Choonhyuck David Kwon,Jongman Kim,Chan Woo Cho,Gaab Soo Kim 대한외과학회 2018 Annals of Surgical Treatment and Research(ASRT) Vol.95 No.4

Purpose: This study aimed to report intraoperative abortion of adult living donor liver transplantation (LDLT). Methods: From June 1997 to December 2016, 1,179 adult LDLT cases were performed. 15 cases (1.3%) of intraoperative abortions in LDLT were described. Results: Among 15 cases, 5 intraoperative abortions were donor-related, and remaining 10 cases were recipient-related. All donor-related abortions were due to unexpected steatohepatitis. Among remaining 10 recipient-related intraoperative abortions, unexpected extension of hepatocellular carcinoma was related in 5 cases. Two cases of intraoperative abortions were related to bowel inflammation, and 2 cases were associated with severe adhesion related to previous treatment. One recipient with severe pulmonary hypertension was also aborted. Conclusion: Complete prevention of aborted LDLT is still not feasible. In this regard, further efforts to minimize intraoperative abortion are required.