Novel potential pyrazolopyrimidine based translocator protein ligands for the evaluation of neuroinflammation with PET

Kwon, Young-Do,Kang, Shinwoo,Park, Hyunjun,Cheong, Il-koo,Chang, Keun-A,Lee, Sang-Yoon,Jung, Jae Ho,Lee, Byung Chul,Lim, Seok Tae,Kim, Hee-Kwon Elsevier 2018 European journal of medicinal chemistry Vol.159 No.-

<P><B>Abstract</B></P> <P>Translocator protein (TSPO) is an interesting biological target because TSPO overexpression is associated with microglial activation caused by neuronal damage or neuroinflammation, and these activated microglia are involved in several central nervous system diseases. Herein, novel fluorinated ligands (<B>14a–c</B> and <B>16a–c</B>) based on a 2-phenylpyrazolo[1,5-<I>a</I>]pyrimidin-3-yl acetamide scaffold were synthesized, and <I>in vitro</I> characterization of each of the novel ligands was performed to elucidate structure activity relationships. All of the newly synthesized ligands displayed nano-molar affinity for TSPO. Particularly, an <I>in vitro</I> affinity study suggests that 2-(5,7-diethyl-2-(4-(3-fluoro-2-methylpropoxy)phenyl)pyrazolo[1,5-<I>a</I>]pyrimidin-3-yl)-<I>N,N</I>-diethylacetamide (<B>14a</B>), which exhibited high nano-molar affinity for TSPO and proper lipophilicity, was suitable for <I>in vivo</I> brain studies. Thus, radiosynthesis from tosylate precursor <B>13a</B> using fluorine-18 was performed, and [<SUP>18</SUP>F]<B>14a</B> was obtained in a 31% radiochemical yield (decay-corrected). Dynamic positron emission tomography (PET) imaging studies were performed in a lipopolysaccharide (LPS)-induced neuroinflammation rat model using [<SUP>18</SUP>F]<B>14a</B> to identify the location of inflammation in the brain with a high target-to-background signal ratio. In addition, we validated that the locations of inflammatory lesions found by PET imaging were consistent with the locations observed by histological examination of dissected brains using antibodies. These results suggest that [<SUP>18</SUP>F]<B>14a</B> is a novel promising PET imaging agent for diagnosing neuroinflammation, and it may also prove to be applicable for diagnosing other diseases, including cancers associated with altered TSPO expression, using PET techniques.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New TSPO ligands with pyrazolopyrimidine core were synthesized. </LI> <LI> <I>K</I> <SUB>i</SUB> value of <B>14a</B> was 3.12 nM. </LI> <LI> <I>In vivo</I> PET imaging of [<SUP>18</SUP>F]<B>14a</B> showed its high uptake in neuroinflammatory region. </LI> <LI> Immunohistochemical study confirmed selective binding of [<SUP>18</SUP>F]<B>14a.</B> </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

우산 빗물 제거용 Air Jet Dryer 장치

권용휘(Yong-Whee Kwon),김선조(Sun-Jo Kim),권용찬(Yong-Chan Kwon),김인환(In-Hwan Kim),임현준(HyunJune Yim) 대한기계학회 2019 대한기계학회 논문집. Transactions of the KSME. C, 산업기술과 혁신 Vol.7 No.3

우산 빗물 받이용 일회용 비닐봉투를 실질적으로 대체할 수 있도록 Air Jet를 이용한 우산의 빗물을 제거 장치를 설계하였다. 우산의 크기와 다양한 모양을 모두 사용 가능하도록 Open형 거치대에 우산의 지지대를 올려놓으면 작동되는 Touch형 스위치를 통해 작동이 용이하도록 설계하였다. 이를 위해 Water Droplet이나 Water Film에 작용하는 외력을 분석하였다. 유동장의 특성은 기본 CFD tool인 Discovery Live를 이용하여 공기 유동장 해석을 수행하였다. Air Jet Reflector는 사용자에게 물방울이 튀기지 않고 반사시키도록 설계하였으며, 그 밖에 배수구, 이동용 바퀴 등을 기본 설계안으로부터 수정하여 보완하였다. 이를 통해 친환경적 Air Jet 우산 빗물 제거기를 구현하였다. 공공 기관이 다수가 사용하는 상업 시설의 입구에 설치하면 1회용 우산 빗물 받이용 비닐의 사용을 획기적으로 감소시킬 수 있다. To practically replace disposable plastic bags for receiving rainwater from umbrellas, a rainwater removal system was designed by using an air jet blower. It was designed to be easy to operate through the touch type switch which was operated by placing the support of the umbrella on the open type holder so that the size and various shapes of the umbrella can be used. For this purpose, the external force acting on the water droplet or water film was analyzed. The flow field was analyzed using the Discovery Live, a basic CFD tool. Air Jet Reflector was designed to reflect water droplets to users, and drainage, wheels, etc. have been modified from the basic design. Through this, an eco-friendly air jet umbrella rain water removal system was developed. When installed at the entrance of commercial facilities used by many public institutions, the use of disposable umbrella rain gowns can be significantly reduced.

A Reconfiguration Method for Preserving Network Bandwidth and Nodes Energy of Wireless Sensor Networks

( Hyunjun Jung ),( Dongwon Jeong ),( Byung-won On ),( Doo-kwon Baik ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.5

In Wireless Sensor Networks (WSNs) and even in the Internet of Things (IoT) ecosystem, the reconfiguration of sensor variables is an important problem when the role of a system (or application) program`s sensor nodes needs to be adjusted in a particular situation. For example, the outdoor temperature in a volcanic zone, which is usually updated in a system every 10 s, should be updated every 1 s during an emergency situation. To solve this problem, this paper proposes a novel approach based on changing only a set of sensor variables in a part of a program, rather thanmodifying the entire program, in order to reduce both network congestion and the sensor nodes` battery consumption. To validate our approach, we demonstrate an implementation of a proof-of-concept prototype system and also present results of comparative studies showing the performance and effectiveness of our proposed method.

Flexible Hybrid Tranparent Conducting Films for Werable Thermal Sensor and Heaters Based on Metallized Fibers and Nanowires

Hyunjun Seok,Hyuk-Jin Kwon,Hong Seok Jo,Sam S. Yoon 한국신재생에너지학회 2019 AFORE Vol.2019 No.11

Development of Portable Water Barrier for the Flood Damage Mitigation

Jae Hyouk LEE,Philshik Kim,Hyunjun Park,Hyungjoong Kwon,Bumjun Choi 한국방재학회 2014 한국방재학회 학술발표대회논문집 Vol.2014 No.-

Although flood and drought have ceaselessly taken place, recently the scale of disasters by them has become incomparably bigger than that of the past, and frequency of flood has rapidly on the increase (Harim et al, 2013). According to National Emergency Management, the frequency of torrential downpours over 30mm per hour was average 3.8 times for last 30 years and average 5.2 times for recent 5 years. Number of days with localized torrential downpour over 80mm per day has increased by 1.5 times for the same period. In addition, recently with the change of climate in Korea, the severity of drought has intensified in 6- to 7-year cycle and, with such reasons as excessive intake of stream water, streams are drying up, especially during spell of dry weather (Maeng, Seung Jin et al, 2013). Even though the government, as countermeasures for these problems, has made efforts to prevent disasters by establishing Water Resources Integrated Development 10-year Plan and Water Resources Long-term Integrated Development Plan, implementing Stream & River Improvement Projects and constructing multi-purpose dams, there are difficulties to promptly cope with rapidly changing weather conditions, requiring urgently measures to minimize damages from droughts and floods. This study developed Portable Multi-purpose Water Barrier (Pocket Dam) which can promptly cope with floods and localized torrential downpour, secure agricultural water by temporarily blocking irrigational channel and drainage during drought and has wide applicability to various areas. To develop Portable Multi-purpose Water Barrier, this study i) selected ultra-light materials for easy mobility ii) chose optimum standards applying MIDAS program iii) verified safety features through field applications. For the maximization of blocking effect as well as the lightening of product, Sol Tarpaulin (PVC-coated polyester) was selected that has endurance against water pressure and excellent gripping force on irregular ground bottom. In addition, by using 3-dimensional structural program MIDAS, the barrier was designed in such a structure that it will not be destroyed or pushed behind by water pressure. As the result of the application of developed barrier on Dorim stream in Gwanak-gu and underground parking lot in Kwangjin-gu, Seoul, the barrier was not destroyed or pushed behind, and, instead, it maintained constant standing position and blocked water, proving that it has diverse applicability in addition to safety features in structure and material.

네트워크 커버리지를 이용한 센서 레지스트리 시스템 확장

정현준 ( Hyunjun Jung ),정동원 ( Dongwon Jeong ),이석훈 ( Sukhoon Lee ),백두권 ( Doo-kwon Baik ) 한국정보처리학회 2015 한국정보처리학회 학술대회논문집 Vol.22 No.1

센서 레지스트리 시스템(Sensor Registry System, SRS)은 이기종 센서 네트워크 환경에서 센서 데이터의 즉각적 활용 및 끊김 없는 해석을 위해 사용자에게 센서 정보를 제공한다. 불안정한 네트워크 상황에서 지속적인 서비스 제공을 위해서 이동 경로 예측기반 SRS 가 연구되었다. 하지만 네트워크가 지원되지 않거나 신호가 약한 지역에서는 여전히 센서 정보의 끊임 없는 제공이 어렵다. 이 논문에서는 이러한 문제를 해결하기 위해, 네트워크 커버리지의 정보를 이용한 센서 레지스트리 시스템 확장 방법을 제안한다. 제안 방법은 예측한 경로와 네트워크 커버리지에 대한 오픈 데이터(지역 통신사 정보, 통신 대역폭, 신호 강도, 통신 타입)를 이용하여 사용자가 불안정한 네트워크 지역에 도착하기 전에 해당 지역의 센서 정보를 추가로 송신한다. 기존의 경로 예측기반 SRS 의 센서 정보 송신보다 추가 오버헤드가 발생하지만, 사용자는 끊김 없는 센서 정보를 수신하여 이용 센서 응용 서비스의 품질을 높일 수 있다.

위상최적화를 적용한 철도차량 전두부 충돌 성능 향상에 관한 연구

김현준(Hyunjun Kim),배철호(Chulho Bae),김세훈(Sehoon Kim),정현승(Hyunseung Jung),권태수(Taesoo Kwon),서명원(Myungwon Suh) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2007 No.11

마찰력현미경을 이용한 나노스케일 마멸시험 시 다이아몬드 탐침으로의 MoS₂ 마멸입자 전이현상

송현준(Hyunjun Song),임형우(Hyeongwoo Lim),성권일(Kwon Il Seong),안효석(Hyo Sok Ahn) 한국트라이볼로지학회 2019 한국윤활학회지(윤활학회지) Vol.35 No.5

In friction and wear tests that use friction force microscopy (FFM), the wear debris transfer to the tip apex that changes tip radius is a crucial issue that influences the friction and wear performances of films and coatings with nanoscale thicknesses. In this study, FFM tests are performed for bilayer MoS₂ film to obtain a better understanding of how geometrical and chemical changes of tip apex influence the friction and wear properties of nanoscale molecular layers. The critical load can be estimated from the test results based on the clear distinction of the failure area. Scanning electron microscopy and energy-dispersive spectroscopy are employed to measure and observe the geometrical and chemical changes of the tip apex. Under normal loads lower than 1000 nN, the reuse of tips enhances the friction and wear performance at the tip-sample interface as the contact pair changes with the increase of tip radius. Therefore, the reduction of contact pressure due to the increase of tip radius by the transfer of MoS₂ or Mo-dominant wear debris and the change of contact pairs from diamond/MoS₂ to partial MoS₂ or Mo/MoS₂ can explain the critical load increase that results from tip reuse. We suggest that the wear debris transfer to the tip apex should be considered when used tips are repeatedly employed to identify the tribological properties of ultra-thin films using FFM.

NIST 암호 표준화 공모전 동향

김현준(Hyunjun Kim),박재훈(Jaehoon Park),권혁동(Hyeokdong Kwon),서화정(Hwajeong Seo) 한국정보보호학회 2020 情報保護學會誌 Vol.30 No.6

NIST에서는 앞으로 다가올 사물인터넷 환경과 양자 컴퓨터 시대를 대비하기 위해 2019년부터 경량암호 표준화 공모전을 그리고 2017년부터 양자내성암호 표준화 공모전을 각각 진행해 오고 있다. 경량암호 표준화 공모전은 경량 블록암호 운영모드를 통해 저전력 사물인터넷 환경 상에서 높은 가용성을 만족하는 암호 개발을 그리고 양자내성암호 표준화 공모전은 양자컴퓨터 상에서의 양자알고리즘으로부터 안전한 공개키 암호 개발을 각각 목표로 하고 있다. 본 고에서는 차세대 암호의 표준화에 큰 영향을 미치게 될 NIST 경량암호 그리고 양자내성암호 표준화 공모전 동향을 상세히 확인해 보도록 한다.

실시간 연필 렌더링

이현준(Hyunjun Lee),권성태(Sungtae Kwon),이승용(Seongyong Lee) 한국컴퓨터그래픽스학회 2005 컴퓨터그래픽스학회논문지 Vol.11 No.4