간섬유화스캔을 이용한 선천성 담도 폐쇄증의 최적 수술시기 시험적 제안

이화영,박영아,한석주,고홍,Lee, Hwa-Young,Park, Young-A,Han, Seok-Joo,Koh, Hong 대한소아소화기영양학회 2011 Pediatric gastroenterology, hepatology & nutrition Vol.14 No.1

목 적: 선천성 담도폐쇄증의 일차적 치료로 알려진 Kasai 수술에서의 가장 중요한 예후 인자로 수술 시기가 중요하다는 것은 기존의 연구 결과들을 통해 잘 알려져 있다. 본 연구에서는 선천성 담도 폐쇄증 환아들을 수술 시기별로 분류하고 간섬유화 스캔을 수술 전후에 시행하여 얻어진 간탄성률값을 이용하여 수술 전후의 간 섬유화 변화를 비교함으로서 본 연구에서 도출된 최적의 수술시기가 기존의 연구와 일치하는지 재확인 하고자 한다. 방 법: 2007년 10월부터 2010년 7월까지 단일 기관에서 Kasai 수술을 시행 받은 환자 중, 수술 전후로 간섬유화 스캔을 시행한 환자 34명을 대상으로 수술 시기별 간탄성률 결과값을 비교하였다. 결 과: 환자군의 수술 시기가 빠를수록 수술 전과 후 모두에서 간탄성률 결과값은 좋았고, 특히 8주 이전에 수술을 시행 받은 경우 그 이상에서 수술을 받은 환자군보다 수술 후의 간섬유화가 적게 진행되었고 일부에서는 회복되었다. 또한 8주 수술 전후의 각 탄성률 간의 차이값 또한 통계적으로 유의하였다. 결 론: Kasai 수술의 시기가 이를수록 수술 전 간 섬유화가 적고, 적어도 8주 이전에서 Kasai 수술을 시행하였을 때 수술 이후의 간섬유화가 양호하였으며 수술전후의 간섬유화 진행 정도가 크지 않았다. 따라서 본 연구에서는 간섬유화스캔을 바탕으로 적어도 8주 미만의 연령이 Kasai 수술을 시행 받기에 최적의 시기임을 재확인하였다. Purpose: Based on previous research findings, it is well-known that the timing of surgery is generally considered the most important prognostic factor for a Kasai portoenterostomy, the primary treatment for biliary atresia. This research aimed to identify the optimal timing of a Kasai portoenterostomy and to verify if the proposed optimal timing corresponds to previous studies. All patients were classified by the timing of surgery, and pre- and post-operative fibrotic changes of the liver were measured with the elasticity value from fibroscans. Methods: The stiffness scores of the pre- and post-operative fibroscans in 34 patients who were treated by Kasai portoenterostomy from October 2007 to September 2010 in Severance children's hospital were reviewed. Results: The earlier the patients were treated by Kasai portoenterostomy, the lower the fibroscan scores. When the patients were treated prior to the 8th week, the post-operative scores of the fibroscans were significantly better than those patients who were treated after the 8th week, and some even recovered partially. Moreover, when operated before the 8th week, the differences between each pre- and postoperative fibroscan score also showed statistical relevance (p=0.0002). Conclusion: The earlier the patient was treated by Kasai portoenterostomy, the less liver fibrosis that developed, the lower the level of post-operative fibrosis, and the less the degree of fibrotic progress before and after the operation. Thus, this research proposal reconfirms once more that the 8th week is the optimal timing for a Kasai portoenterostomy.

임신중기 임산부의 산화스트레스와 영아의 출생 후 1년까지의 성장과의 연관성평가를 위한 예비조사

박혜숙(Byesook Park),김영주(Young Ju Kun),이화영(Hwa Young Lee),박은애(Eun Ae Park),장남수(Nam Soo Chang),하은희(Eun Hee Ha),박보현(Bo Hyun Park),이보은(Bo Eun Lee),홍주희(Ju Hee Hong) 한국역학회 2004 Epidemiology and Health Vol.26 No.1

Objectives: We aims to construct Infant Growth Cohort for evaluating whether oxidative stress in midterm pregnancy has an adverse effect on postnatal growth Methods and materials: From September 2001 to April 2004, we constructed an Ewha Infant Growth Cohort connected with the Ewha Pregnant Women Cohort We excluded mother-and-child pans in which the mother had experienced hypertension or diabetes during pregnancy and had multiple births for this study, which gave us 233 mother-and-child pairs for analysis We measured maternal serum homocysteine and urinary 8-hydroxyguanosine (8-OHdG) and malondialdehyde (MDA) at 24~28 weeks of pregnancy, and infant weights at birth and at 6 and 12 months postnatally We applied repeated-measures ANOVA with PROC MIXED to assess the significance of differences Results: We followed 64 and 85 infants at 6 and 12 months respectively The mean body weights were 3146 4 g at birth, 8229.7 g at 6 months, and 1006.47 g at 12 months The mean birth weight of Infants was lower in mothers with higher homocysteine levels (third and fourth quartiles), but body weights from the first-and fourth-quartile groups of maternal homocysteine levels lower than the others even though It was not statistically significant Body weights at birth and at 6 months in third- and fourth-quartile groups of 8-OHdG levels were lower than the others The body weights In the fourthquartile MDA group were significantly lower than the others at all time points. Conclusions: Maternal Oxidative stress In midterm pregnancy may cause postnatal growth retardation But, there were high late of follow up loss and various measurement errors Therefore, we need to have efforts for compete follow up and valid and reliable measurements.

임산부의 Myeloperoxidase 유전자다형성과 혈중 비타민 C 수준에 따른 모체의 산화 스트레스와 출생체중

박보현(Bohyun Park),김영주(Young-Ju Kim),박은애(Eun Ae Park),이화영(Hwayoung Lee),하은희(Eun-Hee Ha),박종순(Jongsoon Park),김정연(Jeongyoun Kim),홍윤철(Yun-Chul Hong),박혜숙(Hyesook Park) 한국독성학회 2004 Toxicological Research Vol.20 No.3

This study aimed to determine the association of maternal oxidative stress and<br/> adverse pregnancy outcome with serum vitamin C concentration and a myeloperoxidase (MPO)<br/> genetic polymorphism during pregnancy. We investigated 450 pregnant women who visited Ewha<br/> Womans University Hospital for prenatal care during gestational weeks 24~28. During the second trimester,<br/> we measured serum vitamin C levels and urinary 8-hydroxyde-2'-deoxyguanosine (8-OHdG)<br/> and malondialdehyde (MDA) as an oxidative stress biomarker. We determined the presence of a<br/> maternal MPO polymorphism (G-to-A substitution at nucleotide 463) using a PCR-RFLP assay. We<br/> compared the level of oxidative stress and birth weight with the vitamin C concentration and the<br/> presence of the MPO polymorphism. The mean level of maternal oxidative stress tended to be<br/> higher and the birth weight lower for MPO type A/A than for types A/G and G/G. Vitamin C levels<br/> above the 75 percentiles were associated with reduced concentrations of urinary MDA and 8-OHdG<br/> but increased birth weight. Our data demonstrate that oxidative stress and neonatal birth weight are<br/> associated with the MPO genetic polymorphism, with the association modified by the maternal vitamin<br/> C levels.

임산부의 혈중 엽산과 호모시스틴 수준이 태반세포의 DNA 메틸화에 미치는 영향

박보현,김영주,이화영,하은희,민정원,박종순,박혜숙,Park, Bo-Hyun,Kim, Young-Ju,Lee, Hwa-Young,Ha, Eun-Hee,Min, Jung-Won,Park, Jong-Soon,Park, Hye-Sook 대한예방의학회 2005 예방의학회지 Vol.38 No.4

Objectives : DNA methylation is one of the best characterized epigenetic mechanisms that play a regulatory role in genome programming and imprinting during embryogenesis. In this present study, we investigated the association between DNA methylation in the human placenta and the maternal folate and homocysteine concentrations on the Methylenetetrahydrofolatereductase (MTHFR) genetic polymorphism during pregnancy. Methods : We investigated 107 pregnant women who visited Ewha Woman's University Hospital for prenatal care during their $24{\sim}28$ weeks-period of gestation. During the second trimester, we measured the serum homocysteine and folate concentrations . The MTHFR 677 genetic polymorphism was determine by performing PCR-RFLP assay. The expression of DNA methylation in the human placentas was estimated by using immunohistochemistry method. Results : Serum folate was negatively correlated with the serum homocysteine concentration for all the MTHFR genotypes. We found positive correlation between the folate concentrations and the DNA methylation in the human placenta (p<0.05). An increasing concentration of homocysteine was associated with reduced DNA methylation in the human placenta. The coefficient value was -2.03 (-3.77, -0.29) on the regression model (p<0.05). Conclusion : These findings suggest that the maternal folate and homocysteine levels along with the MTHFR 677 genetic polymorphism during pregnancy affect the DNA methylation in the human placenta.

학생의 정의적 성취 신장을 위한 수학교육 개선 방향 탐색

이화영 ( Lee Hwayoung ),고호경 ( Ko Ho Kyoung ),박지현 ( Park Ji Hyun ),오세준 ( Oh Se Jun ),임미인 ( Lim Miin ) 한국수학교육학회 2022 수학교육 Vol.61 No.4

It has been alerted that Korean students' mathematical affective achievement is very low. In order to solve this problem, various policies related to mathematical affective domains have been promoted, but it is necessary to examine various existing policies and explore the direction for improving them in more essential aspects. Based on previous studies that the growth mindset helps to increase students' affective achievement, this study focused on improving students’ math-related growth mindset and ultimately exploring policies that can increase mathematical affective achievement. Therefore, the current status of mathematical affective achievement of Korean students was examined, and the policies and related cases in the mathematical affective domain were investigated. Based on the results, some keywords were derived and then the directions of policy for improving the math-related growth mindset and the affective achievement of students were suggested.

유압식 하이브리드 파워트레인 시뮬레이터 및 제어 로직개발을 통한 연비 성능 분석

이화영(HWAYOUNG LEE),김예림(YERIM KIM),박지예(JIYE PARK),민현지(HYEONJI MIN),홍유진(HONGYOU JIN),최희성(HEESUNG CHOI),황성호(SUNG-HO HWANG),신외경(WAE GYEONG SHIN) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11

Hydraulic Hybrid Vehicle(HHV) is a hybrid vehicle using hydraulic motor/pump and accumulators to save regenerative energy instead of electric motors and Li-ion batteries. This system is known that it has up to 35% fuel saving effect and 90% increased driving distance, but has not been commercialized because of cost uncertainty issue compared to Hybrid electric vehicles(HEVs). Therefore, a HHV powertrain simulation model was developed using a software platform for hydraulic system analysis in this paper, and it used for comparing the fuel saving effect according to driving strategies. And down-scaled bench test model of a HHV powertrain was built up to be run by driving strategies and powersplit control for verifying the fuel saving effect.

단일 3축 가속도센서를 사용한 보행 시 대사에너지 예측

이화영 ( Hee Young Lee ),김승현 ( Seung Hyeon Kim ),이동엽 ( Dong Yeop Lee ),박선우 ( Sun Woo Park ),김영호 ( Young Ho Kim ) 한국운동역학회 2011 한국운동역학회지 Vol.21 No.2

The purpose of this study was to compare metabolic energy expenditure with the computed kinetic energy for different speeds of walking and running over the treadmill and to find the relevance for individual and group equation by performing a statistical analysis, Bland-Altman plot. Seven male subjects participated, and they were required to walk and run on the treadmill with the gas analyzer and triaxial accelerometer. Walking speeds were 3.0, 4.0, 5.0 and 6.0 km/h and running speeds were 7.0, 8.0 and 9.0 km/h respectively. Kinetic energy was calculated by the integration of acceleration data and compared with the metabolic energy measured by a gas analyzer. Correlation coefficients showed relatively good between the measured metabolic energy and the calculated kinetic energy. In addition, a dramatic increase in kinetic energy was also observed at the transition speed of walking and running, and two standard deviations in Bland-Altman plot, derived from the difference between measured and predicted values, were 1.14, 2.53, 2.93, 1.80, 2.80, 0.60 and 2.48 respectively. It was showed that there is no difference for methods of how to predict the kinetic energy expenditure for individual and group even though people had each different physical characteristic.

Lack of Acceptance of Digital Healthcare in the Medical Market: Addressing Old Problems Raised by Various Clinical Professionals and Developing Possible Solutions

Park Jong Il,이화영,Kim Hyunah,이지산,Shinn Jiwon,김헌성 대한의학회 2021 Journal of Korean medical science Vol.36 No.37

Various digital healthcare devices and apps, such as blood glucose meters, blood pressure monitors, and step-trackers are commonly used by patients; however, digital healthcare devices have not been widely accepted in the medical market as of yet. Despite the various legal and privacy issues involved in their use, the main reason for its poor acceptance is that users do not use such devices voluntarily and continuously. Digital healthcare devices generally do not provide valuable information to users except for tracking self-checked glucose or walking. To increase the use of these devices, users must first understand the health data produced in the context of their personal health, and the devices must be easy to use and integrated into everyday life. Thus, users need to know how to manage their own data. Medical staff must teach and encourage users to analyze and manage their patient-generated healthcare data, and users should be able to find medical values from these digital devices. Eventually, a single customized service that can comprehensively analyze various medical data to provide valuable customized services to users, and which can be linked to various heterogeneous digital healthcare devices based on the integration of various health data should be developed. Digital healthcare professionals should have detailed knowledge about a variety of digital healthcare devices and fully understand the advantages and disadvantages of digital healthcare to help patients understand and embrace the use of such devices.

신재생에너지를 위한 원격 모니터링 시스템

이화영(H. Y. Lee),박중제(J. J. Park),김남호(N. H. Kim) 한국기계가공학회 2022 한국기계가공학회 춘추계학술대회 논문집 Vol.2022 No.4

금속 결함 검사를 위한 와전류 탐상 기반의 비파괴 검사 시스템

이화영(H. Y. Lee),박중제(J. J. Park),김남호(N. H. Kim) Korean Society for Precision Engineering 2021 한국정밀공학회 학술발표대회 논문집 Vol.2021 No.11월

최근 생산라인뿐 아니라 발전소와 같은 산업기반시설이나 대형 플랜트, 초고층 빌딩, 초대형 다리, 대형 경기장의 구조물과 같은 시설물 및 고압 송유관, 석유화학공장의 고압 파이프 등 많은 시설물의 안전 진단이 중요 시 되고 있다. 이에 따라, 빠른 처리속도, 다채널, 고감도의 인-라인용 실시간 비파괴 검사에 대한 요구가 증가하고 있다. 비파괴 검사는 구조물, 제품 등 검사 대상체를 분해하거나 파괴하지 않고 원형 그대로의 형태에서 결함, 안전도, 수명 등을 진단하여 하자를 보수하거나 품질을 관리할 수 있는 검사 방법이다. 와전류 탐상 방식은 비파괴 검사의 대표적인 방법으로 표면상 또는 표면 바로 아래의 미세균열, 홀, 이물질 등을 검출하는데 효과적이며, 매질 없이 비접촉으로 검사를 진행하는 장점이 있다. 와전류 검사는 검체의 형태나 표면 특징에 따라 다양한 검출 성능을 지니며 미세한 결함 검출과 자동화를 실현하기 위해 다양한 연구가 진행되고 있다. 본 논문에서는 금속 매질에 존재하는 결함의 상태에 따른 와전류 검사의 출력을 비교, 분석하기 위하여 폭과 깊이가 다른 크랙이 존재하는 금속 시편을 사용하고, 프로브에 인가되는 신호의 주파수와 센싱 속도 등을 조절하였다. 와전류 검사의 출력을 비교, 분석한 결과 결함의 폭과 깊이에 따른 검출 특성이 우수하였다.