Real-time imaging of glioblastoma using bioluminescence in a U-87 MG xenograft model mouse

Kim, Woong,Kang, Bo Ram,Kim, Hye Yun,Cho, Soo Min,Lee, Yong-Deok,Kim, Sehoon,Kim, Jung Young,Kim, Dong Jin,Kim, YoungSoo The Korean Society for Applied Biological Chemistr 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.2

Glioblastoma multiforme (GBM), the most common malignant brain tumor, is characterized by aggressive proliferation and invasive potential. Xenograft animal models of GBM have critically contributed to evaluation of novel therapeutic agents, drug delivery system, and diagnostic tools. To mimic intrinsic behavior of GBM, orthotopic transplantation of cancer cells and continuous observation of cell growth should be conducted in animal study. Here, we generated xenograft model mouse of GBM in which U-87 MG human glioblastoma cells were intracranially implanted for live imaging. Introducing luciferase gene into U-87 MG cell line enabled real-time observation and quantification of tumor survival and propagation by detecting photon emission derived from luciferase. Our GBM model mouse has potentials to bring great advantages in pharmacological and mechanistic investigation on brain tumors.

A Case Study of Korea Military Academy (KMA) Leadership Education

Sehoon, Kim(김세훈) 대한리더십학회 2014 리더십연구 Vol.5 No.1

지식은 형식에 따라 크게 두 가지로 나눌 수 있는데, 먼저 언어와 같은 상징으로 표현될 수 없는 암묵지가 있다. 이에 반해, 학교교육과 같이 교실에서 언어를 매개로 학습될 수 있는 형식지가 있다. 언어화되고, 문서화된 지식이 대표적인 형식지 의 예이다. 그런데 리더십은 단순하게 교실에서 강의를 통해서 배울 수 없는 과목이다. 오히려 학습자들은 다른 리더십 롤 모델을 관찰하거나 혹은 직접 리더로서의 경험을 해봄으로서 리더십을 학습할 수 있다. 이러한 측면에서 사람들은 리더로서 혹 은 팔로워로서 리더십을 수행하고 이를 통해 배운다고 할 수 있다. 따라서 리더십과 같은 과목의 경우 우리는 암묵지의 형식으로 학습이 될 수 있다고 할 수 있다. 마치 자전거 타는 원리를 배우기 위해 자이로스코프의 원리를 배우지 않아도, 기술을 터득하면 자전거를 쉽게 탈 수 있는 것과 마찬가지로 말이다. 이런 점에서 리더십은 직접 체득하고, 관찰함으로서 학습할 수 있다고 여겨진다. 즉, 리더십 교육은 수공 업, 상업 또는 예술 및 예능 활동에서 장인의 지도로 실습을 통해 기능을 습득하는 도제제도의 학습과 유사성을 찾을 수 있다. 도제제도에 대해 Lave & Wenger(1991) 는 ‘합법적 주변참여‘ 개념을 이용하여 이러한 학습이 일어나는 과정을 설명하고 있 다. 본 연구는 사관학교에의 리더십 학습이 이러한 도제제도와 유사한 방식으로 이루어지고 있다고 본다. 예를 들어, 육군사관학교는 실질적인 리더십 활동 및 경험을 보장해 주기 위해 ‘지휘근무제도’를 마련해 주고 있다. 본 논문은 국내 및 외국 육군 사관학교의 리더십 교육에 대해 분석하고, 이를 ’합법적 주변참여‘의 개념으로 설명하였다. 이를 통해 육군사관학교가 리더십 교육의 도장으로 기여하는 바가 적지 않음을 제시하고자 하였다. Knowledge can be divided with implicit and explicit knowledge. Explicit knowledge is also called as public or propositional knowledge, which learns in formal education settings such as schools and vocational training centers. Implicit knowledge is earned through experiences, reflections, or trial-error practices. Leadership competency is a subject to acquire through informal ways rather than formal methods as if we don't learn a theory to ride a bicycle. Leadership competency can be improved by experience, observation, and application. Lave and Wenger (1991) advocates the concept of peripheral participation to explain how learners are educated and matured while they attend a community of practice called "Self-Governed System." It is differentiated from an apprenticeship system due to legitimacy because all cadets are required to join a community of practice which is employed to develop leadership competency. This study pursues to introduce the system of a leadership education which Korea Military Academy(KMA) have been applying to develop leadership competency of military cadets. In particular, this study focus on the mechanism of how the concept of peripheral participation apples to leadership development programs.

Reduced risk for chronic kidney disease after recovery from metabolic syndrome: A nationwide populationbased study

( Sehoon Park ),( Soojin Lee ),( Yaerim Kim ),( Yeonhee Lee ),( Min Woo Kang ),( Kyungdo Han ),( Hajeong Lee ),( Jung Pyo Lee ),( Kwon Wook Joo ),( Chun Soo Lim ),( Yon Su Kim ),( Dong Ki Kim ) 대한신장학회 2020 Kidney Research and Clinical Practice Vol.39 No.2

Background: Metabolic syndrome (MetS) is linked to various chronic comorbidities, including chronic kidney disease (CKD). However, few large studies have addressed whether recovery from MetS is associated with reduction in the risks of such comorbidities. Methods: This nationwide population-based study in Korea screened 10,664,268 people who received national health screening ≥ 3 times between 2012 and 2016. Those with a history of major cardiovascular events or preexisting CKD were excluded. We classified study groups into four, according to the course of MetS state, as defined by the harmonizing criteria. The main study outcome was incidental CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m² which was persistent until the last health exams). The study outcomes were investigated using multivariable logistic regression analysis, which was adjusted for clinical variables and the previous severity of MetS. Results: Four study groups included 6,315,301 subjects: 4,537,869 people without MetS, 1,034,605 with chronic MetS, 438,287 who developed MetS, and 304,540 who recovered from preexisting MetS. Those who developed MetS demonstrated higher risk of CKD (adjusted odds ratio [OR], 1.26 [1.23-1.29]) than did those who did not develop MetS. In contrast, MetSrecovery was associated with decreased risk of CKD (adjusted OR, 0.84 [0.82-0.86]) than that in people with chronic MetS. Among the MetS components, change in hypertension was associated with the largest difference in CKD risk. Conclusion: Reducing or preventing MetS may reduce the burden of CKD on a population-scale. Clinicians should consider the clinical importance of altering MetS status for risk of CKD.

Measurement of the Thermally Induced Bit Error Rate in a Single Flux Quantum Switch

Sehoon Kim,Jinyoung Kim,Joonhee Kang 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.46 No.4

The measurement of the bit error rate (BER) is very important in digital electronics devices. If a credible superconductive arithmetic logic unit (ALU) is to be made, a rapid single flux quantum (RSFQ) switch should have a very low error rate. In this experiment, we prepared two circuits placed in parallel. Each circuit had 10 Josephson transmission lines (JTLs) connected in series with an RSFQ switch placed in the middle of the 10 JTLs. We used a splitter to feed the same input signal to both circuits. The outputs of the two circuits were compared with an RSFQ XOR (exclusive OR gate) to measure the BER of the RSFQ switch. Since the JTLs had very wide margins, we assumed the error rates of the JTLs to be much lower than those of the switches. We observed no bit error during a 4-hour operation at a 500 kHz data rate and calculated the BER of the RSFQ switch to be less than 1.38 × 10−10. We also observed no bit errors during 2 hours of operation at a 5 MHz data rate and calculated the BER to be less than 2.78 × 10−11.

Contrast Induced Nephropathy after Outpatient Computed Tomography Examinations

( Sehoon Park ),( Eunjeong Kang ),( Hajeong Lee ),( Kwon Wook Joo ),( Yon Su Kim ),( Dong Ki Kim ) 대한내과학회 2015 대한내과학회 추계학술대회 Vol.2015 No.1

Background: Most studies regarding contrast induced nephropathy (CIN) were done in angiography era. However computed tomography (CT) is more common cause of contrast exposure in general populaton. There were few prognosis data concerning CIN after outpatient CT. Methods: Chronic kidney disease (CKD) patients with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 underwent outpatient CIN prophylaxis program for contrast CT from 2008 to 2014 in Seoul National University Hospital. Patients received intravenous isotonic saline and oral N-acetylcysteine (NAC). Baseline blood sample was done within 2 weeks before CT. Basic data was colleted retrospectively by medical chart review. Prognosis was surveyed from death registry of National Statics Korea and dialysis registry of The Korean Society of Nephrology. CIN was defined by ≥0.5 mg/dl or ≥25% increase of serum creatinine (sCr) from baseline within 48-96 hours after CT. Primary outcome was event of renal replacement therapy (RRT), duration from CT to RRT and survival period after CT. Results: 12,179 cases of CT were performed with CIN prophylaxis protocol and 2816 cases of CT had baseline eGFR <60 without RRT history and follow up sCr 48-96 hours after CT. 84 (3%) cases of CIN were found and 99 (3.5%) cases went RRT, 551 death reported after CT. Prognosis was analyzed after adjustment with age, sex, baseline eGFR, history of diabetes and hypertension. No statisticalsignificant relationship between death, RRT incidence, doubling of sCr and CIN was shown. However, we found shorter period from CT to RRT in CIN cases. This relationship disappeared when analysis was done excluding RRT start within 6 months. Conclusions: Incidence of CIN was low after outpatient CT with appropriate prophylaxis measures. CIN was not a significant risk factor of long term mortality or renal function aggravation. CIN was only a risk factor for acute period start of RRT.

Characteristics of kidney transplantation recipients over time in South Korea

Sehoon Park,김명석,Ji Eun Kim,Kwangsoo Kim,Minsu Park,Yong Chul Kim,Kwon Wook Joo,Yon Su Kim,Hajeong Lee 대한내과학회 2020 The Korean Journal of Internal Medicine Vol.35 No.6

Background/Aims: Detailed nationwide information regarding the recent status and time trends of kidney transplantation (KT) in South Korea is limited. Methods: We performed a nationwide, population-based cohort study using the national claims database of Korea. We included KT recipients from 2008 to 2016, and their demographic and clinical characteristics were collected. The prognostic outcome was graft failure consisted of patient death and death-censored graft failure (DCGF). Results: We studied 14,601 KT recipients with median follow-up duration of 3.96 years. The median age at the time of transplantation consistently increased from the past, and proportion of underlying diabetes mellitus prominently increased, reaching 35.6% in 2016. The preemptive KT accounted for approximately 30% of the total transplantation cases. The recipients showed a 10-year cumulative graft survival rate of 71.8%, consisting of 10-year DCGF free survival of 77.6% and patient survival of 92.8%. Age ≥ 20 and < 30 years, age ≥ 70 years, underlying history of diabetes, non-preemptive transplantation, and poor compliance on tacrolimus and mycophenolic acid were the significant risk factors associated with worse DCGF outcome. The economic cost of KT showed prominently increasing trends, reaching a total insured fee of > 60,000,000$ in 2016. However, the expansion was mainly burdened by the national insurance service but not by the patients. Conclusions: In South Korea, the number of kidney transplantation in elderly or in patients with comorbidities has been increasing. Complex clinical factors were associated with medication compliance and patient prognosis.

Risk of cancer in pre-dialysis chronic kidney disease: A nationwide population-based study with a matched control group

( Sehoon Park ),( Soojin Lee ),( Yaerim Kim ),( Yeonhee Lee ),( Min Woo Kang ),( Kyungdo Han ),( Seoung Seok Han ),( Hajeong Lee ),( Jung Pyo Lee ),( Kwon Wook Joo ),( Chun Soo Lim ),( Yon Su Kim ),( 대한신장학회 2019 Kidney Research and Clinical Practice Vol.38 No.1

Background: Cancer risk and epidemiology in pre-dialysis chronic kidney disease (CKD) warrant further investigation in a large-scale cohort. Methods: We performed a nationwide population-based study using the national health insurance database of Korea. We screened records from 18,936,885 individuals who received a national health examination ≥ 2 times from 2009 to 2016. Pre-dialysis CKD was identified based on serum creatinine and dipstick albuminuria results. Individuals with preexisting cancer history, renal replacement therapy, or transient CKD were excluded. A control group without evidence of kidney function impairment and matched for age, sex, low-income status, and smoking history was included. Risk of cancers, as identified in the claims database, was investigated using a multivariable Cox regression model including matched variables and other unmatched clinical characteristics as covariates. Results: A total of 471,758 people with pre-dialysis CKD and the same number of matched controls were included. Urinary (adjusted hazard ratio [HR], 1.97; 95% confidence interval [95% CI], 1.82-2.13) and hematopoietic (adjusted HR, 1.53; 95% CI, 1.38-1.68) malignancy risk was increased in pre-dialysis CKD and all CKD stages. However, the risk of digestive cancer was lower in the pre-dialysis CKD group (adjusted HR, 0.89; 95% CI, 0.87-0.92). The risk of digestive, respiratory, thyroid, and prostate malignancy demonstrated a non-linear association with CKD stage, with stage 1 or stage 4/5 CKD without dialysis demonstrating relatively lower risk. Conclusion: Cancer risk varied in pre-dialysis CKD compared to controls, and the association between cancer risk and CKD stage varied depending on the cancer type.

The Recent Trend of FCEV Market and the Development of Composite Overwrapped Pressure Vessels

Sehoon Kim(김세훈) 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.2

Fuel cell electric vehicle is one of the important transportation system when we can choose environmental friendly mobility. Recently, many developed countries are focused on carbon neutral society, the electric vehicle has been taking main role of green mobility. The EV has been greatly improved on the efficiency of battery system and competitive cost with the government subsides. Additionally, the FCEV is also valuable options we can use for eco-friendly mobility because the power sources are oxygen and hydrogen and the emission of FCEV is just water. Although the limited automakers can produce commercial scale FCEV, many global OEMs have announced their FCEV plan in the near future. The main system of FCEV is fuel cell and hydrogen storage system which can endure high operating pressure at about 700 bar. We have been developing new manufacturing process of composite overwrapped pressure vessel for mass production and briefly introduce the recent development status.

Surveillance of hard ticks (Acarina: Ixodidae) as Severe Fever with Thrombocytopenia Syndrome (SFTS) virus vectors in the Republic of Korea, 2022

Sehoon Cho,SoEun Shin,Hyunwoo Kim,Byung-Eon Noh,Tae-Kyu Kim,Wook-Gyo Lee,Hee Il Lee 한국응용곤충학회 2023 한국응용곤충학회 학술대회논문집 Vol.2023 No.04

ESG Lending

Sehoon Kim,Nitish Kumar,Jongsub Lee,Junho Oh 한국재무학회 2021 한국재무학회 학술대회 Vol.2021 No.11

The \ESG lending" market, where loan contract terms are contingent on borrower ESG performance (i.e., ESG-linked loans), or where loans are issued for specic green projects (i.e., Green loans), has grown exponentially from $6 billion in 2016 to $173 billion in 2019. Much of this growth is driven by ESG-linked loans which are widespread across various industries and well developed capital markets, especially in civil law countries. ESG-linked loans are issued in sizeable amounts by large and publicly listed borrowers, and are often structured through revolving credit facilities by large groups of syndicates led by reputable \ESG specialist" global banks, who keep tight relationships with borrowers. Green loans are smaller project nance vehicles, similar in format to green bonds, yet issued to mostly privately held borrowers. They do not tend to attract large cross-border syndicates. We nd that ESG loans tend to be written by borrowers and lenders with superior ESG proles ex-ante, and nd no evidence that their ESG performances deteriorate ex-post after ESG loan issuance. Overall, our results indicate that borrowers capable of maintaining high ESG standards and lenders capable of coordinating and monitoring ESG loan contracts drive the emergence of ESG banking activities around the globe.