Association of Substantia Nigra Degeneration with Poor Neurological Recovery in Basal Ganglia Infarctions

Kijeong Lee,HyungWoo Lee,Young Dae Kim,Hyo Suk Nam,Hye Sun Lee,Joonsang Yoo,Sunghee Cho,Ji Hoe Heo 대한뇌졸중학회 2023 Journal of stroke Vol.25 No.1

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The aniline-to-azobenzene oxidation reaction on monolayer graphene or graphene oxide surfaces fabricated by benzoic acid

Lee, Myungjin,Kim, Kijeong,Lee, Hangil Springer 2013 NANOSCALE RESEARCH LETTERS Vol.8 No.1

<P>The oxidation of aniline to azobenzene was conducted in the presence of either monolayer graphene (EG) or graphene-oxide-like surface, such as GOx, under ultra-high vacuum conditions maintaining a 365-nm UV light exposure to enhance the oxidation reaction. The surface-bound products were investigated using micro Raman spectroscopy, high-resolution photoemission spectroscopy, and work function measurements. The oxygen carriers present on the GOx surfaces, but not on the EG surfaces, acted as reaction reagents to facilitate the oxidation reaction from aniline to azobenzene. Increasing the aniline concentration at 300 K confirmed that the exchange ratio from the aniline to the azobenzene was enhanced, as determined by the intensity ratio between the aniline- and azobenzene-induced N 1 <I>s</I> core-level spectra. The work function changed dramatically as the aniline concentration increased, indicating that the aniline on the GOx surface conveyed <I>n</I>-type doping characteristics at a low coverage level. A higher aniline concentration increased the <I>p</I>-type doping character by increasing the azobenzene concentration on the GOx surface. A comparison of the oxidation reactivity of aniline molecules on the EG or GOx surfaces revealed the role of the oxygen carriers on the GOx surfaces in the context of catalytic oxidation.</P>

Which one to do first?: a case report of simultaneous acute ischemic stroke and myocardial infarction

Lee Kijeong,Park Woohyun,Seo Kwon-Duk,Kim Hyeongsoo 대한신경집중치료학회 2021 대한신경집중치료학회지 Vol.14 No.2

Background: Although there are common risk factors for acute ischemic stroke and myocardial infarction, simultaneous onset of both diseases is uncommon. Here, we present a case of acute cerebral infarction with concurrent fatal myocardial infarction. Case Report: A 54-year-old man presented with left hemiparesis, gaze preponderance to the right side, and visual and tactile extinction. Computed tomography angiography showed occlusion of the right middle cerebral artery. ST-elevation myocardial infarction was suspected on electrocardiography. After the injection of intravenous tissue plasminogen activator, thrombectomy was attempted first, and the coronary angiogram was planned after recanalization of the cerebral artery. However, thrombectomy was discontinued because of cardiac arrest. Despite extracorporeal membrane oxygenation and emergency percutaneous coronary intervention, the patient died of multiorgan failure.Conclusion: Double primary acute ischemic stroke and myocardial infarction are rare but may be fatal due to the narrow therapeutic time window for both diseases. Careful consideration of the urgency of cardiac status is essential.

Lenticulostriate Artery Involvement is Predictive of Poor Outcomes in Superficial Middle Cerebral Artery Territory Infarction

Lee, Kijeong,Kim, Eun Hye,Song, Dongbeom,Kim, Young Dae,Nam, Hyo Suk,Lee, Hye Sun,Heo, Ji Hoe Yonsei University, College of Medicine 2017 Yonsei medical journal Vol.58 No.1

<P><B>Purpose</B></P><P>Patients with superficial middle cerebral artery (MCA) territory infarction may have concomitant lenticulostriate artery (LSA) territory infarction. We investigated the mechanisms thereof and the outcomes of patients with superficial MCA territory infarction according to the presence or absence of LSA involvement.</P><P><B>Materials and Methods</B></P><P>Consecutive patients with first-ever infarction in the unilateral superficial MCA territory were included in this study. They were divided into the superficial MCA only (SM) group and the superficial MCA plus LSA (SM+L) group.</P><P><B>Results</B></P><P>Of the 398 patients, 84 patients (21.1%) had LSA involvement (SM+L group). The SM+L group more frequently had significant stenosis of the proximal MCA or carotid artery and high-risk cardioembolic sources. Stroke severity and outcomes were remarkably different between the groups. The SM+L group showed more severe neurologic deficits (National Institute of Health Stroke Scale score 10.8±7.1 vs. 4.0±5.0, <I>p</I><0.001) and larger infarct in the superficial MCA territory (40.8±62.6 cm<SUP>3</SUP> vs. 10.8±21.8 cm<SUP>3</SUP>, <I>p</I><0.001) than the SM group. A poor functional outcome (mRS >2) at 3 months was more common in the SM+L group (64.3% vs. 15.9%, <I>p</I><0.001). During a mean follow-up of 26 months, 67 patients died. All-cause (hazard ratio, 2.246) and stroke (hazard ratio, 9.193) mortalities were higher in the SM+L group than the SM group. In multivariate analyses, LSA involvement was an independent predictor of poor functional outcomes and stroke mortality.</P><P><B>Conclusion</B></P><P>LSA territory involvement is predictive of poor long-term outcomes in patients with superficial MCA territory infarction.</P>

Identification of Novel A2/C2 Inter-Genotype Recombinants of Hepatitis B Virus from a Korean Chronic Patient Co-Infected with Both Genotype A2 and C2

Lee, So-Young,Lee, Seung-Hee,Kim, Ji-Eun,Kim, Hong,Kim, Kijeong,Kook, Yoon-Hoh,Kim, Bum-Joon MDPI AG 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.4

<P>Nearly all cases of Hepatitis B virus (HBV) infections in South Korea have the C2 genotype. Here, we have identified a chronically infected patient who was co-infected with HBV of both the A2 and C2 genotypes by screening 135 Korean chronically infected patients using direct sequencing protocols targeting the 1032-bp polymerase reverse transcriptase (RT) region. Further polymerase chain reaction (PCR)-cloning analysis (22 clones) of the RT showed that this patient had genotype C2 (12 clones), genotype A2 (six clones) and A2/C2 inter-genotype HBV recombinants (four clones). BootScan analysis showed that three of the four recombinants have different types of recombination breakpoints in both the RT and overlapping hepatitis B surface antigen (HBsAg) region. Given the significance of HBsAg as a diagnostic or vaccination target against HBV infection, clinical implications of these identified recombinants should be studied in the future. To our knowledge, this is the first report on A2/C2 inter-genotype HBV recombinants.</P>

건강보험 청구자료를 이용한 한국인 염증성 관절염 환자의 뇌졸중 발생 분석

Kijeong Lee,Jung-Kyu Choi,Jin-su Park,Jung Yoon Pyo,Minkyung Han,Jun Hong Lee 대한임상노인의학회 2022 대한임상노인의학회지 Vol.23 No.2

Background: Inflammation is an important mechanism in stroke. To a considerable extent, the pathophysiology of inflammatory arthritis is influenced by inflammatory cells and cytokines. We compared the risk of stroke between patients with inflammatory arthritis and matched controls, using data from the National Health Insurance Service. Methods: Using a combination of primary diagnosis and V codes for rare incurable diseases, we defined the patients with ankylosing spondylitis, seropositive rheumatoid arthritis, and psoriatic arthritis and enteropathic spondyloarthropathy. The control group was defined by 1:5 propensity score-matching for each disease. Newly developed stroke was identified in the patients with the primary diagnosis of (I60-64) and 1) brain imaging or 2) a prescription of stroke medication or related intervention. Results: The occurrence of stroke was more frequently associated with seropositive rheumatoid arthritis in both the patient population and the seropositive rheumatoid arthritis control group (hazard ratio 1:11, 95% CI 1.02-1.20, P=0.012). In this study, the frequency of stroke occurrence was not associated with the diagnosis of ankylosing spondylitis nor psoriatic arthritis or enteropathic spondyloarthropathy. Furthermore, the use of biologic agents was not associated with the occurrence of stroke, using multivariable analyses in the three different types of inflammatory arthritis and their respective control groups. Conclusion: Seropositive rheumatoid arthritis was a predictor of frequent stroke occurrences. The patients with seropositive rheumatoid arthritis must be cautious with regard to the occurrence of a comorbid stroke. Further studies with long-term follow-ups of clinical outcomes are warranted to explain the underlying correlation between inflammatory arthritis and the risk of stroke.

Effects of treadmill exercise-intensity on short-term memory in the rats born of the lipopolysaccharide-exposed maternal rats

Kim, Kijeong,Sung, Yun-Hee,Seo, Jin-Hee,Lee, Sang-Won,Lim, Baek-Vin,Lee, Choong-Yeol,Chung, Yong-Rak 한국운동재활학회 2015 JER Vol.11 No.6

<P>Maternal infection is an important factor causing neonatal brain injury and later developmental disability. In the present study, we investigated the effects of treadmill exercise intensity on short-term memory, hippocampal neurogenesis, and expression of brain-derived neurotrophic factor (BDNF), and tyrosine kinase receptor B (TrkB) in the rats born of lipopolysaccharide (LPS)-exposed maternal rats. The rats were divided into six groups: control group, mild-intensity exercise group, moderate-intensity exercise group, maternal LPS-exposed group, maternal LPS-exposed and mild-intensity exercise group, maternal LPS-exposed and moderate-intensity exercise group. The rats in the exercise groups were forced to run on a treadmill for 30 min 5 times a week for 4 weeks. The exercise load consisted of running at the speed of 8 m/min for the mild-intensity exercise groups and 14 m/min for moderate-intensity exercise groups. The latency in the step-down avoidance task was deter-mined for the short-term memory. Immunohistochemistry for 5-bro-mo-2′-deoxyuridine was performed to determine hippocampal cell proliferation and neurogenesis. Western blot analysis was performed for the detection of BDNF and TrkB expression. In the present study, tread-mill exercise improved short-term memory deteriorated by maternal LPS exposure. Treadmill exercise increased cell proliferation and neurogenesis in the hippocampal dentate gyrus of the rats born of the LPS-exposed maternal rats. Treadmill exercise increased BDNF and TrkB expression in the hippocampus of the rats born of the LPS-exposed maternal rats. These effects of treadmill exercise were similarly appeared at both mild-intensity and moderate-intensity.</P>

ATO over ETCS의 자동운전 속도프로파일 연산을 위한 ATO-ATP 인터페이스에 대한 고찰

이기정(Kijeong Lee),홍구선(Goo Sun Hong),김경식(Kyoung Shik Kim),성동일(Dong Il Sung) 한국철도학회 2020 한국철도학회 학술발표대회논문집 Vol.2020 No.7

ORF: FMIPv6 네트워크에서 핸드오버 지연 감소를 위한 최적화된 라우팅 기법 성능 분석

이기정(Kijeong Lee),박병주(Byungjoo Park),박길철(Gil-cheol Park) 한국정보기술학회 2009 Proceedings of KIIT Conference Vol.2009 No.-

IPv6에 이동성 부여를 위해 IETF(Internet Engineering Task Force)에서 제안한 MIPv6 (Mobile IPv6) 는 이동 노드(MN: Mobile Node) 가 이동 중에도 상대 노드(CN: Correspondent Node) 와의 인터넷 연결이 지속되도록 하기 위해 핸드오버 절차가 필요하다. 이때 발생되는 지연문제 해결을 위해 IETF에서는 FMIPv6 (Fast handover for MIPv6) 를 제안하였다. FMIPv6는 기존 MIPv6의 긴 핸드오버 지연시간을 단축시키고 라우터 터널링을 통해 패킷손실 문제를 보완했지만 여전히 서브넷 사이를 빈번하게 이동할 경우 발생되는 과도한 핸드오버 지연시간 문제가 남아있다. 본 논문에서는 MN이 하나의 도메인 내에서 각각의 라우터 사이를 짧은 시간 내 여러 번 이동할 경우 발생하는 긴 핸드오버 지연시간을 줄이고 이때 발생되는 패킷손실 문제 해결을 위한 라우팅 알고리즘을 제안한다. The Mobile IPv6(MIPv6) that was standardized by Internet Engineering Task Force(IETF) was designed to provide mobility in IPv6 networks but there is need of handover for maintaining connection between Mobile Node(MN) and Corresponding Node(CN) while MN is moving. The IETF standardized the Fast handover for Mobile IPv6(FMIPv6) in order to solve the problem in delay and packet loss which caused by the handover. FMIPv6 reduces handover latency of MIPv6 and makes up for packet loss. However, the handover latency is still a problem when MN moves frequently between each sub-nets. In this paper we propose an Optimized Routing Algorithm in FMIPv6 Networks for reduction of handover latency and to solve packet loss problem when MN moves frequently between each sub-nets.

ERSF: 무선 모바일 네트워크에서 향상된 QoS를 위한 고속 핸드오버 기반의 강화된 라우팅 기법

이기정(Kijeong Lee),박병주(Byungjoo Park),장병윤(Byeong-Yun Chang) 한국정보기술학회 2010 한국정보기술학회논문지 Vol.8 No.5

The Mobile IPv6 (MIPv6) that was standardized by Internet Engineering Task Force (IETF) is in need of handover for maintaining internet connection between Mobile Node (MN) and Corresponding Node (CN) while MN is moving. The IETF standardized the Fast handover for Mobile IPv6 (FMIPv6) in order to minimize the problem in delay and packet loss which caused by the handover. FMIPv6 reduces handover latency of MIPv6 and makes up for packet loss. However, the handover latency is still a problem when MN moves frequently between each subnets. In this paper we propose an optimized routing algorithm in FMIPv6 networks and analyze the performance for reduction of handover latency and to minimize packet loss problem when MN moves frequently between each subnets.