Relative impact of amyloid-β, lacunes, and downstream imaging markers on cognitive trajectories

Kim, Hee Jin,Yang, Jin Ju,Kwon, Hunki,Kim, Changsoo,Lee, Jong Min,Chun, Phillip,Kim, Yeo Jin,Jung, Na-Yeon,Chin, Juhee,Kim, Seonwoo,Woo, Sook-young,Choe, Yearn Seong,Lee, Kyung-Han,Kim, Sung Tae,Kim, Oxford University Press 2016 Brain Vol.139 No.9

<P>Amyloid-beta deposition and cerebral small vessel disease are major contributors to age-related cognitive decline. In a longitudinal study of mild cognitive impairment, Kim et al. show that amyloid-beta and lacunes have differing effects on cognitive trajectories. Amyloid-beta has a greater impact on memory, and lacune number on frontal-executive function.Amyloid-beta and cerebral small vessel disease are the two major causes of cognitive impairment in the elderly. However, the underlying mechanisms responsible for precisely how amyloid-beta and cerebral small vessel disease affect cognitive impairment remain unclear. We investigated the effects of amyloid-beta and lacunes on downstream imaging markers including structural network and cortical thickness, further analysing their relative impact on cognitive trajectories. We prospectively recruited a pool of 117 mild cognitive impairment patients (45 amnestic type and 72 subcortical vascular type), from which 83 patients received annual follow-up with neuropsychological tests and brain magnetic resonance imaging for 3 years, and 87 patients received a second Pittsburgh compound B positron emission tomography analysis. Structural networks based on diffusion tensor imaging and cortical thickness were analysed. We used linear mixed effect regression models to evaluate the effects of imaging markers on cognitive decline. Time-varying Pittsburgh compound B uptake was associated with temporoparietal thinning, which correlated with memory decline (verbal memory test, unstandardized beta = -0.79, P < 0.001; visual memory test, unstandardized beta = -2.84, P = 0.009). Time-varying lacune number was associated with the degree of frontoparietal network disruption or thinning, which further affected frontal-executive function decline (Digit span backward test, unstandardized beta = -0.05, P = 0.002; Stroop colour test, unstandardized beta = -0.94, P = 0.008). Of the multiple imaging markers analysed, Pittsburgh compound B uptake and the number of lacunes had the greatest association with memory decline and frontal-executive function decline, respectively: Time-varying Pittsburgh compound B uptake (standardized beta = -0.25, P = 0.010) showed the strongest effect on visual memory test, followed by time-varying temporoparietal thickness (standardized beta = 0.21, P = 0.010) and time-varying nodal efficiency (standardized beta = 0.17, P = 0.024). Time-varying lacune number (standardized beta = -0.25, P = 0.014) showed the strongest effect on time-varying digit span backward test followed by time-varying nodal efficiency (standardized beta = 0.17, P = 0.021). Finally, time-varying lacune number (beta = -0.22, P = 0.034) showed the strongest effect on time-varying Stroop colour test followed by time-varying frontal thickness (standardized beta = 0.19, P = 0.026). Our multimodal imaging analyses suggest that cognitive trajectories related to amyloid-beta and lacunes have distinct paths, and that amyloid-beta or lacunes have greatest impact on cognitive decline. Our results provide rationale for the targeting of amyloid-beta and lacunes in therapeutic strategies aimed at ameliorating cognitive decline.</P>

Cost-Effectiveness of Rivaroxaban Compared to Warfarin for Stroke Prevention in Atrial Fibrillation

Kim, Hyunmee,Kim, Hyeongsoo,Cho, Seong-Kyung,Kim, Jin-Bae,Joung, Boyoung,Kim, Changsoo The Korean Society of Cardiology 2019 Korean Circulation Journal Vol.49 No.3

<P><B>Background and Objectives</B></P><P>Rivaroxaban is noninferior to warfarin for preventing stroke or systemic embolism in patients with high-risk atrial fibrillation (AF) and is associated with a lower rate of intracranial hemorrhage (ICH). We assessed the cost-effectiveness of rivaroxaban compared to adjusted-dose warfarin for the prevention of stroke in patients with nonvalvular AF.</P><P><B>Methods</B></P><P>We built a Markov model using the Korean Health Insurance Review & Assessment Service database. The base-case analysis assumed a cohort of patients with prevalent AF who were aged 18 years or older without contraindications to anticoagulation.</P><P><B>Results</B></P><P>Number of patients with CHA<SUB>2</SUB>DS<SUB>2</SUB>-VASc scores 0, 1 and ≥2 were 56 (0.2%), 1,944 (6.3%) and 28,650 (93.5%), respectively. In patients with CHA<SUB>2</SUB>DS<SUB>2</SUB>-VASc scores ≥2, the incidence rate of ischemic stroke was 3.11% and 3.76% in warfarin and rivaroxaban groups, respectively. The incidence rates of ICH were 0.42% and 0.15%, and those of gastrointestinal bleeding were 0.32% and 0.15% in warfarin and rivaroxaban, respectively. Patients with AF treated with rivaroxaban lived an average of 11.8 quality-adjusted life years (QALYs) at a lifetime treatment cost of $20,886. Those receiving warfarin lived an average of 11.4 QALYs and incurred costs of $17,151. Patients with rivaroxaban gained an additional 0.4 QALYs over a lifetime with an additional cost of $3,735, resulting in an incremental cost-effectiveness ratio of $9,707 per QALY.</P><P><B>Conclusions</B></P><P>Patients who had been treated with rivaroxaban may be a cost-effective alternative to warfarin for stroke prevention in Korean patients with AF.</P>

Electrochemical Partial Reduction of Ni(OH)₂ to Ni(OH)₂/Ni via Coupled Oxidation of an Interfacing NiAl Intermetallic Compound for Hydrogen Evolution

Changsoo Lee,Younghwa Yun,Kwangsoo Kim,Byung-Seon An,Ji Hee Kwon,Sechan Lee,Jae Hun Lee,MinJoong Kim,Sang-Kyung Kim,Jong Hyeok Park,Byung-Hyun Kim,Hyun-Seok Cho 한국신재생에너지학회 2022 AFORE Vol.2022 No.9

Practical deployment of pipelines for the CCS network in critical conditions using MINLP modelling and optimization: A case study of South Korea

Kim, Changsoo,Kim, Kyeongsu,Kim, Jeongnam,Ahmed, Usama,Han, Chonghun Elsevier 2018 INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL Vol.73 No.-

<P><B>Abstract</B></P> <P>In applying Carbon Capture and Storage (CCS) technology, pipelines are an economic choice for transporting CO<SUB>2</SUB>. However, it is difficult to plan the pipeline network in detail since various factors, such as mountain regions and high population density increase the cost of pipeline installation. Also, uncertainty of the reservoir capacity and national policies is important factors in practical pipeline deployment, especially in critical conditions mentioned above.</P> <P>In this study, the development of an optimal CCS pipeline network in critical conditions, and the effect of practical design conditions on the network, are studied using mixed-integer nonlinear programming (MINLP) modeling and optimization. South Korea is selected as a case study and optimal CCS networks are obtained according to four scenarios developed with regard to reservoir capacity and policy options. A rigorous cost model was developed, and subdivided penalty factors were applied to consider the drastic change in geographical conditions. The four scenarios were evaluated and the effect of the considered factors on the timely development of the CCS network was analyzed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Framework for CCS network design in critical conditions is proposed. </LI> <LI> Effect of reservoir uncertainty and CCS policy options is analyzed. </LI> <LI> Policy options affect the network design more than reservoir uncertainty. </LI> </UL> </P>

Surface spin wave mode and reversal of gyromagnetic ratio in ferrimagnetic thin film

Changsoo Kim,Soogil Lee,Kyoung-Woong Moon,Byong-Guk Park,Se Kwon Kim,Kab-Jin Kim,Chanyong Hwang 한국자기학회 2019 한국자기학회 학술연구발표회 논문개요집 Vol.29 No.2

Clinical effect of white matter network disruption related to amyloid and small vessel disease

Kim, Hee Jin,Im, Kiho,Kwon, Hunki,Lee, Jong-Min,Kim, Changsoo,Kim, Yeo Jin,Jung, Na-Yeon,Cho, Hanna,Ye, Byoung Seok,Noh, Young,Kim, Geon Ha,Ko, En-Da,Kim, Jae Seung,Choe, Yearn Seong,Lee, Kyung Han,Ki Ovid Technologies (Wolters Kluwer) - American Acad 2015 Neurology Vol.85 No.1

<P>We tested our hypothesis that the white matter network might mediate the effect of amyloid and small vessel disease (SVD) on cortical thickness and/or cognition.</P>

Association between body mass index and cortical thickness: among elderly cognitively normal men and women

Kim, Hojeong,Kim, Changsoo,Seo, Sang Won,Na, Duk L.,Kim, Hee Jin,Kang, Mira,Shin, Hee-Young,Cho, Seong Kyung,Park, Sang eon,Lee, Jeongmin,Hwang, Jung Won,Jeon, Seun,Lee, Jong-Min,Kim, Geon Ha,Cho, Han Cambridge University Press 2015 INTERNATIONAL PSYCHOGERIATRICS - Vol.27 No.1

<B>ABSTRACT</B><B>Background:</B><P>There is increasing evidence of a relationship between underweight or obesity and dementia risk. Several studies have investigated the relationship between body weight and brain atrophy, a pathological change preceding dementia, but their results are inconsistent. Therefore, we aimed to evaluate the relationship between body mass index (BMI) and cortical atrophy among cognitively normal participants.</P><B>Methods:</B><P>We recruited cognitively normal participants (<I>n</I> = 1,111) who underwent medical checkups and detailed neurologic screening, including magnetic resonance imaging (MRI) in the health screening visits between September 2008 and December 2011. The main outcome was cortical thickness measured using MRI. The number of subjects with five BMI groups in men/women was 9/9, 148/258, 185/128, 149/111, and 64/50 in underweight, normal, overweight, mild obesity, and moderate to severe obesity, respectively. Linear and non-linear relationships between BMI and cortical thickness were examined using multiple linear regression analysis and generalized additive models after adjustment for potential confounders.</P><B>Results:</B><P>Among men, underweight participants showed significant cortical thinning in the frontal and temporal regions compared to normal weight participants, while overweight and mildly obese participants had greater cortical thicknesses in the frontal region and the frontal, temporal, and occipital regions, respectively. However, cortical thickness in each brain region was not significantly different in normal weight and moderate to severe obesity groups. Among women, the association between BMI and cortical thickness was not statistically significant.</P><B>Conclusions:</B><P>Our findings suggested that underweight might be an important risk factor for pathological changes in the brain, while overweight or mild obesity may be inversely associated with cortical atrophy in cognitively normal elderly males.</P>

컴퓨터단층영상에서 TIA를 이용한 간경화의 컴퓨터보조진단

김창수(Changsoo Kim),고성진(Seong-Jin Ko),강세식(Se-Sik Kang),김정훈(Jung-Hoon Kim),김동현(Donghyun Kim),최석윤(Seokyoon Choi) 한국콘텐츠학회 2012 한국콘텐츠학회논문지 Vol.12 No.4

간경화(liver cirrhosis)는 섬유조직의 증식과 재생성 결절 형성의 형태학적인 변화로 2차적으로 간내혈관의 변형 및 간기능의 저하가 나타나는 질병이며, 정맥류, 복수와 부종, 간성뇌증, 간암 등의 합병증 동반을 미연에 방지하는 것이 간경변증 진단 및 치료에 핵심이다. 일반적으로 간 컴퓨터단층영상이 간경변의 진단 및 병기를 결정하는 방법으로 사용한다. 그러므로 본 연구에서는 간경화의 자동 인식을 위하여 PCA와 TIA 알고리즘을 이용한 특징추출을 통하여 간경변의 자동 검출능력을 알아보고, 각 알고리즘간의 성능을 비교하였다. 실험은 학습영상과 테스트영상으로 구분한다. 고유영상을 생성시키기 위한 학습영상으로 정상영상이 사용되고, 테스트영상으로는 간경화영상이 사용된다. 간 CT 영상에서 간의 질병 부위를 균등하게 ROI 설정하고, 50×50 픽셀 크기로 영상을 저장하여 실험하였다. 실험결과로 PCA는 간경화 검출율이 35%로 질병 인식으로 부적합하며, TIA 알고리즘의 AGL, TM. MU, EN는 100% 질병 인식력을 나타내어 간경화 자동 진단 인식으로 가능했다. 또한 결과를 임상에 적용하여 간경변의 컴퓨터보조진단으로 활용한다면 영상의학과 의사에게 업무 부담을 줄이고, 일차적 간경변의 스크리닝 도구로서 활용이 가능할 것이다. 그리고 TIA 알고리즘을 활용한 자동진단은 질병 진단의 전단계로서 예비판독의 정보를 제공하며 간경변의 조기 진단 및 예방이 가능다고 판단된다. Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules leading to loss of liver function. Liver Cirrhosis is most commonly caused by alcoholism, hepatitis B and C, and fatty liver disease, but has many other possible causes. Some cases are idiopathic disease from unknown cause. Abdomen of liver Computed tomography(CT) is one of the primary imaging procedures for evaluating liver disease such as liver cirrhosis, Alcoholic liver disease(ALD), cancer, and interval changes because it is economical and easy to use. The purpose of this study is to detect technique for computer-aided diagnosis(CAD) to identify liver cirrhosis in abdomen CT. We experimented on the principal components analysis(PCA) algorithm in the other method and suggested texture information analysis(TIA). Forty clinical cases involving a total of 634 CT sectional images were used in this study. Liver cirrhosis was detected by PCA method(detection rate of 35%), and by TIA methods(detection rate of 100%-AGI, TM, MU, EN). Our present results show that our method can be regarded as a technique for CAD systems to detect liver cirrhosis in CT liver images.

후쿠시마 원전 사고 후 방사선 및 원전에 대한 인식 분석

김창수(Changsoo Kim),김동현(Dong-Hyun Kim),김정훈(Jung-Hoon Kim) 한국콘텐츠학회 2013 한국콘텐츠학회논문지 Vol.13 No.9

본 연구는 부산광역시 거주민을 대상으로 배경 변인에 따라 방사선에 대한 지식, 지식수준의 지각, 방사선의 편익과 원자력 위험에 대한 인식, 그리고 후쿠시마 원전 사고 관련 정보수집과 인식 등은 어떻게 다른지를 알아보기 위한 목적으로 진행되었다. 분석을 위한 연구 대상은 414명의 거주민이다. 그 결과, 조사대상자들은 방사선의 필요성은 원칙적으로 인정하나 안전성에 대해서는 부정적인 인식을 가지고 있는 것으로 분석되었다. 이러한 부정적 인식은 방사선에 대한 지식을 기반으로 한 것이 아니라 과거 원전 사고 등에 기인한 것으로 판단되며, 향후 올바른 인식 전환을 위해서는 미디어를 통한 방사선과 원자력에 대한 교육과 홍보 그리고 방사선지식의 폭을 넓히고 나아가 보다 다양한 측면에서 시민들의 인식 변화를 위한 노력이 필요하다고 사료된다. Based on surveys of Busan residents, this study aimed to analyze general perception: radiation knowledge, recognition of the standard of knowledge, radiation benefits, recognition of the risks of nuclear power, collection of information on the Fukushima nuclear accident, recognition of changes before and after the Fukushima nuclear accident, and the path of collecting information about nuclear power and radiation. This analysis was based on 414 people who reside in Busan metropolitan city. It has been found that the Busan metropolitan city residents acknowledged the necessity of radiation in principle, however, most have negative awareness relating to safety. It is assumed that this negative awareness is a result from past nuclear power plant accidents, rather than being based on their own knowledge of radiation. Therefore, it is considered that efforts to change people’s awareness necessitate education of the public. This can be done via media, widening the range of people’s knowledge, and furthermore, promoting changes within people’s awareness and perspectives.

Steer-by-Wire 시스템을 위한 조향감 향상

김창준(Changjun Kim),김현수(Hyunsoo Kim),김기헌(Kiheon Kim),한창수(Changsoo Kim) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper is about steering system of Steer-by-Wire(SBW). As a SBW system is applied in order to improve steering feel and maneuverability, the controller should have two purposes. One is controlling steering wheel for the driver's steering feel and the other is controlling the front wheel system for vehicle stability. This study focuses on steering wheel system. The column is reduced in the SBW steering wheel system. Therefore it need artificial steering feel. This is the study for an objective evaluation method with steering angle, steering torque to quantify steering feel of SBW system. Based on this method, the affect two different torque map performance was simulated and compared each other.