Publications by authors named "Young-Seo Kim"

67 Publications

Pure-Sensory Stroke in Pons Presented Isolated Perioral Sensory Symptoms.

Ann Indian Acad Neurol 2021 Jan-Feb;24(1):84. Epub 2020 Sep 2.

Department of Neurology and Institute of Wonkwang Medical Science, Wonkwang University School of Medicine, Iksan, Korea.

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http://dx.doi.org/10.4103/aian.AIAN_595_20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8061529PMC
September 2020

Chemotherapy confers a conserved secondary tolerance to EGFR inhibition via AXL-mediated signaling bypass.

Sci Rep 2021 Apr 13;11(1):8016. Epub 2021 Apr 13.

Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.

Drug resistance remains the major culprit of therapy failure in disseminated cancers. Simultaneous resistance to multiple, chemically different drugs feeds this failure resulting in cancer relapse. Here, we investigate co-resistance signatures shared between antimitotic drugs (AMDs) and inhibitors of receptor tyrosine kinases (RTKs) to probe mechanisms of secondary resistance. We map co-resistance ranks in multiple drug pairs and identified a more widespread occurrence of co-resistance to the EGFR-tyrosine kinase inhibitor (TKI) gefitinib in hundreds of cancer cell lines resistant to at least 11 AMDs. By surveying different parameters of genomic alterations, we find that the two RTKs EGFR and AXL displayed similar alteration and expression signatures. Using acquired paclitaxel and epothilone B resistance as first-line AMD failure models, we show that a stable collateral resistance to gefitinib can be relayed by entering a dynamic, drug-tolerant persister state where AXL acts as bypass signal. Delayed AXL degradation rendered this persistence to become stably resistant. We probed this degradation process using a new EGFR-TKI candidate YD and demonstrated that AXL bypass-driven collateral resistance can be suppressed pharmacologically. The findings emphasize that AXL bypass track is employed by chemoresistant cancer cells upon EGFR inhibition to enter a persister state and evolve resistance to EGFR-TKIs.
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http://dx.doi.org/10.1038/s41598-021-87599-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8044124PMC
April 2021

DeepRegularizer: Rapid Resolution Enhancement of Tomographic Imaging Using Deep Learning.

IEEE Trans Med Imaging 2021 May 30;40(5):1508-1518. Epub 2021 Apr 30.

Optical diffraction tomography measures the three-dimensional refractive index map of a specimen and visualizes biochemical phenomena at the nanoscale in a non-destructive manner. One major drawback of optical diffraction tomography is poor axial resolution due to limited access to the three-dimensional optical transfer function. This missing cone problem has been addressed through regularization algorithms that use a priori information, such as non-negativity and sample smoothness. However, the iterative nature of these algorithms and their parameter dependency make real-time visualization impossible. In this article, we propose and experimentally demonstrate a deep neural network, which we term DeepRegularizer, that rapidly improves the resolution of a three-dimensional refractive index map. Trained with pairs of datasets (a raw refractive index tomogram and a resolution-enhanced refractive index tomogram via the iterative total variation algorithm), the three-dimensional U-net-based convolutional neural network learns a transformation between the two tomogram domains. The feasibility and generalizability of our network are demonstrated using bacterial cells and a human leukaemic cell line, and by validating the model across different samples. DeepRegularizer offers more than an order of magnitude faster regularization performance compared to the conventional iterative method. We envision that the proposed data-driven approach can bypass the high time complexity of various image reconstructions in other imaging modalities.
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http://dx.doi.org/10.1109/TMI.2021.3058373DOI Listing
May 2021

Comparison of patients with transient and sustained increments of antiphospholipid antibodies after acute ischemic stroke.

J Neurol 2021 Feb 6. Epub 2021 Feb 6.

Department of Neurology, College of Medicine, Kyung-Hee University, Seoul, Republic of Korea.

Background And Purpose: Antiphospholipid syndrome (APS) is one of the uncommon causes of ischemic stroke, and is associated with young and female patients. However, the significance of antiphospholipid antibody (aPL) in older ischemic stroke patients is uncertain. We aimed to examine the significance of aPLs in ischemic stroke in these older patients.

Materials And Methods: A total of 739 patients with acute ischemic stroke within 7 days of initial symptoms were collected consecutively. Clinical and laboratory data were obtained from medical records. aPLs (lupus anticoagulant, anti-cardiolipin antibody, anti-β2glycoprotein-I antibody) were measured the day after admission and the presence of at least one antibody was regarded as positive aPL. Patients with positive aPL were rechecked after at least 12 weeks for confirmation of APS.

Result: Of the 739 patients, 103 (13.9%) had at least one aPL initially. These patients were older, had more atrial fibrillation and higher levels of inflammatory markers. Among the 103 aPL positive patients, 41 remained positive at 3 months, 23 showed negative conversion, and 39 were not available for follow-up. Patients diagnosed with APS had higher numbers of aPL and had specifically anti-β2glycoprotein-I IgG antibody. The patients with aPLs did not differ significantly from the others in terms of stroke subtype.

Conclusion: aPL was rather common in ischemic stroke patients regardless of age. Although the influence of transient positive aPL on ischemic stroke remains uncertain, two or more aPLs and the presence of anti-β2glycoprotein-I IgG may predict a diagnosis of APS.
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http://dx.doi.org/10.1007/s00415-021-10432-wDOI Listing
February 2021

Causes, Risk Factors, and Clinical Outcomes of Stroke in Korean Young Adults: Systemic Lupus Erythematosus is Associated with Unfavorable Outcomes.

J Clin Neurol 2020 Oct;16(4):605-611

Department of Neurology, Kyung Hee University College of Medicine, Seoul, Korea.

Background And Purpose: The incidence of ischemic stroke (IS) in young adults is increasing, and the associated large socioeconomic impact makes understanding IS in young adults important. We investigated the causes of and risk factors for IS in young adults, and their impact on outcomes.

Methods: The Stroke in Korean Young Adults (SKY) study is a standardized multicenter prospective study involving eight medical centers of the Republic of Korea. First-ever IS patients aged 18 years to 44 years were prospectively included in this study within 7 days of stroke onset. Their outcomes at 3 months were analyzed.

Results: This study enrolled 270 patients from April 2014 to December 2018, most (67.8%) of whom were male. About 41.5% of the patients had one or more vascular risk factors from among hypertension, diabetes mellitus, and dyslipidemia. However, only half of them had received regular treatment. Arterial dissection was more common in males, and systemic lupus erythematosus (SLE) and Moyamoya disease were more common in females. The outcome was favorable (modified Rankin Scale score of 0 or 1) in 81.9% of the patients at 3 months after stroke onset. More severe initial symptoms, higher initial glucose level, and SLE as a comorbidity were associated with unfavorable outcomes.

Conclusions: Young adult IS patients in Korea exhibit low awareness and poor management of their risk factors. Although the short-term outcome was relatively favorable in those patients, having SLE was associated with unfavorable outcomes. More attention needs to be paid for improving awareness and controlling risk factors in this population.
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http://dx.doi.org/10.3988/jcn.2020.16.4.605DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7541989PMC
October 2020

Homocysteinemia is Associated with the Presence of Microbleeds in Cognitively Impaired Patients.

J Stroke Cerebrovasc Dis 2020 Dec 18;29(12):105302. Epub 2020 Sep 18.

Department of Neurology, College of Medicine, Hanyang University, Seoul, Republic of Korea.

Background & Objective: Homocysteine is possibly associated with cerebral small vessel diseases such as leukoaraiosis, silent brain infarction and cerebral microbleeds, which are in turn associated with cognitive dysfunction. We aimed to examine the relationships between cerebral microbleeds (CMBs) and plasma total homocysteine (tHcy) level, methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and cognitive function.

Methods: A total of 819 patients with memory disturbance who visited a dementia clinic consecutively were included in this study. We retrospectively collected demographic, clinical and laboratory data including tHcy level, MTHFR C677T polymorphism and Mini-Mental State Examination (MMSE). All patients underwent brain MRI including fluid attenuated inversion recovery (FLAIR) image and T2*-weighed gradient-echo (GRE) image. Logistic regression analysis was performed to test the association between risk factors and the presence of microbleeds.

Results: One hundred and sixty-one (19.7%) patients had CMBs, of whom 88 (54.7%) had CMBs in the lobar region. CMBs were more common in older hypertensive male patients with hyperhomocysteinemia. In multivariable analysis, plasma tHcy remained an independent predictor of the presence of CMBs after adjusting other confounders (OR: 1.035, 95% CI: 1.009-1.062, p = 0.009). Higher plasma tHcy level was also associated with number of CMBs, TT MTHFR genotype, and lower MMSE scores.

Conclusions: Elevated plasma tHcy level is related to high prevalence of CMBs and cognitive dysfunction. Lowering plasma tHcy could be helpful in cognitively impaired patients who have CMBs or the MTHFR TT genotype.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2020.105302DOI Listing
December 2020

Variation in Knowledge of Stroke Warning Signs by Age and Presence of Conventional Risk Factors: A Community Health Survey in Korea.

J Cardiovasc Nurs 2020 Jul 29. Epub 2020 Jul 29.

Juyeon Oh, RN, PhD Assistant Professor, College of Nursing, Dankook University, Cheonan, South Korea. Hyun Young Kim, MD, PhD Professor, Department of Neurology, College of Medicine, Hanyang University, Seoul, South Korea. Young Seo Kim, MD, PhD Assistant Professor, Department of Neurology, College of Medicine, Hanyang University, Seoul, South Korea. Sun Hwa Kim, RN, PhD Registered Nurse, Stroke Unit, Department of Nursing, Hanyang University Medical Center, Seoul, South Korea.

Background: It is important to recognize stroke in the general public.

Objectives: The purpose of this study was to investigate factors affecting knowledge of stroke warning signs (SWSs) according to age group in the Korean population.

Methods: This study is a cross-sectional study. Using data from the Korean Community Health Survey conducted in Korea in 2017, 198 403 subjects were analyzed. Knowledge about SWSs was assessed by face-to-face interviews using structured close-ended questionnaires with 5 items about stroke symptoms (sudden unilateral weakness of face, arm or leg; sudden difficulty in speaking, or trouble understanding speech; sudden visual impairment in 1 eye, or double vision; sudden dizziness or loss of balance; and sudden severe headache).

Results: The overall percentage of subjects with good knowledge of SWSs (>4 correct answers to the SWS questionnaire) was 66.5%. It was highest in the middle-aged subjects (72.6%), followed by the young subjects (63.5%) and the older subjects (61.5%). The youngest of the young subjects and the oldest of the older subjects had the least knowledge. Subjects with conventional risk factors generally had more knowledge about SWSs, except for those with diabetes mellitus. However, in the young subjects, knowledge about SWSs was not increased by the presence of conventional risk factors such as hypertension and dyslipidemia.

Conclusion: Stoke risk factors are increasing among young people; they still have poor knowledge about SWSs. More education is needed to increase appropriate treatment, especially in young people with stroke-related risk factors.
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http://dx.doi.org/10.1097/JCN.0000000000000736DOI Listing
July 2020

Computed tomography-negative symptomatic intracerebral hemorrhage in a patient with cerebral small vessel disease: A case report.

Medicine (Baltimore) 2020 Jul;99(29):e21382

Department of Neurology, College of Medicine, Hanyang University, Seoul, Republic of Korea.

Rationale: Computed tomography plays a key role in the initial evaluation of suspected acute stroke by ruling out the possibility of hemorrhage before thrombolysis. Recently, many reports have described cases of symptomatic microbleeds, and there may also have been a case of computed tomography- negative intracerebral hemorrhage.

Patient Concerns: A 70-year-old female patient who had a history of lacunar infarction and severe small vessel disease developed dysarthria. On brain non-contrast computed tomography there was no evidence of intracerebral hemorrhage. However, brain magnetic resonance imaging performed at 3 hours after the initial computed tomography showed cerebral hemorrhage.

Diagnoses: The diagnosis was computed tomography-negative intracerebral hemorrhage.

Interventions: The patient was treated with cilostazole 100 mg twice a day with blood pressure management.

Outcomes: The dysarthria was fully recovered within 5 days and the patient did not suffer recurrent stroke symptoms over the following 2 years.

Lessons: In patients with underlying severe small vessel disease and microbleeds, there could be computed tomography-negative hemorrhage and susceptibility weighted magnetic resonance image could be needed. More attention is required before applying thrombolysis therapy because there is a possibility of cerebral hemorrhage in those patients.
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http://dx.doi.org/10.1097/MD.0000000000021382DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7373521PMC
July 2020

Chronic Gastritis Is Associated with a Decreased High-Density Lipid Level: Histological Features of Gastritis Based on the Updated Sydney System.

J Clin Med 2020 Jun 14;9(6). Epub 2020 Jun 14.

Department of Neurology, Hanyang University College of Medicine, Seoul 04763, Korea.

Chronic gastritis could activate a systemic inflammatory response that could result in adverse lipid profiles. To determine the severity of chronic gastritis, (HP), mononuclear cell (lymphocytes and plasma cells), and neutrophil scores were assessed on the basis of the updated Sydney system (USS), which is widely used for histological grading. The aim of this study was to assess the relationships between gastric histological features and lipid profile levels. This study included 15,322 males and 5929 females who underwent a health checkup and gastric biopsy at the Kangbuk Samsung Medical Center (KBSMC). We analyzed whether the HP, mononuclear cell, and neutrophil grades according to the USS were related to serum leukocyte count, unhealthy behaviors, and lipid profile levels. Gastritis with HP, neutrophils, or moderate to severe mononuclear cells was associated with an elevated serum leukocyte count. A high leukocyte count was related to increased low-density lipoproteins (LDL) and triglycerides/very-low-density lipoprotein (VLDL) and decreased high-density lipoproteins (HDL). In multivariate analyses, chronic gastritis with HP or moderate to severe mononuclear cells was significantly associated with decreased HDL in males, while mononuclear cells were significantly related to decreased HDL in females. Chronic gastritis was associated with an increased systemic inflammatory response, which was associated with unfavorable lipid profiles, especially low HDL levels.
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http://dx.doi.org/10.3390/jcm9061856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7355915PMC
June 2020

Use of methotrexate in the management of recurrent Tolosa-Hunt syndrome: Two case reports.

Medicine (Baltimore) 2020 Apr;99(17):e19882

Department of Neurology.

Rationale: Tolosa-Hunt syndrome (THS) is rare condition characterized by painful ophthalmoplegia that usually responds well to corticosteroid. About a half of THS patients experience recurrence within intervals of months to years from initial presentation. Recurrence is more common in younger patients, and can be ipsilateral, contralateral, or bilateral. Cyclosporine, azathioprine, methotrexate, mycophenolate mofetil, infliximab, and radiotherapy can be considered as second-line treatment. However, there is insufficient evidence for treatments preventing recurrence of THS.

Patient Concerns: We experienced two patients with THS that recurred twice while tapering or after ceasing corticosteroid administration.

Diagnosis: Both patients were diagnosed as recurrent THS.

Interventions: Methotrexate was treated with a combination of corticosteroid after THS recurred twice with corticosteroid therapy alone.

Outcomes: After adding methotrexate to the steroid regimen, their symptoms were successfully regulated and ceased to recur LESSONS:: These cases add to the evidence for the use of methotrexate as a second-line therapeutic agent for those patients with recurrent THS attacks. Further studies are in need to prove the risk and benefits of second-line treatments in THS.
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http://dx.doi.org/10.1097/MD.0000000000019882DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7220784PMC
April 2020

The Different Relationship between Homocysteine and Uric Acid Levels with Respect to the MTHFR C677T Polymorphism According to Gender in Patients with Cognitive Impairment.

Nutrients 2020 Apr 19;12(4). Epub 2020 Apr 19.

Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, 222-1, Wansimni-ro, Seondong-gu, Seoul 04763, Korea.

In an elderly population with cognitive impairment, we investigated the association between serum uric acid (sUA) and serum homocysteine (sHcy), known risk factors for cerebrovascular disease. We also investigated the potential effect of the C677T polymorphism in the gene encoding methylenetetrahydrofolate reductase (MTHFR) to the sUA level in different dementia types. Participants underwent a battery of tests including measurements of sUA, sHcy, folic acid, and vitamin B12 as well as genotyping of the MTHFR locus. Data from 861 subjects (597 females to 264 males) were retrospectively analyzed. Subjects with hyperhomocysteinemia had lower serum folic acid and vitamin B12 and higher sUA than those with normal sHcy. sUA was significantly associated with serum creatinine, HbA1c, and sHcy regardless of gender. The TT genotype was found to be associated with hyperhomocysteinemia in both genders ( = 0.001). The levels of hyperlipidemia, sHcy, and sUA differed according to dementia subtypes. High sUA were associated with hyperhomocystenemia in TT genotype only in dementia with vascular lesion. This study reveals that sUA is positively associated with sHcy. We speculate that the two markers synergistically increase cerebrovascular burden and suggested that dietary intervention for sUA and sHcy would be helpful for cognitive decline with vascular lesion.
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http://dx.doi.org/10.3390/nu12041147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230180PMC
April 2020

Early increment of soluble triggering receptor expressed on myeloid cells 2 in plasma might be a predictor of poor outcome after ischemic stroke.

J Clin Neurosci 2020 Mar 14;73:215-218. Epub 2020 Feb 14.

Department of Neurology, Hanyang University College of Medicine, Seoul, Republic of Korea; Department of Translational Medicine, Hanyang University Graduate School of Biomedical Science & Engineering, Seoul, Republic of Korea. Electronic address:

Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) is derived from cleavage of TREM2, which is expressed on the cell surface of microlgia and other tissue-specific macrophages. In the present study, the changes in the sTREM2 levels after ischemic stroke (IS) and their association with clinical outcomes were evaluated. A total of 43 patients diagnosed with non-cardioembolic IS between June 2011 and May 2014 were consecutively included in this study. Patients treated with intravenous thrombolysis or intra-arterial thrombectomy were excluded. Plasma samples were collected three times (days 1, 7, and 90) after ictus. The sTREM2 level was measured in the samples using the highly sensitive solid-phase proximity ligation assay (SP-PLA). Among the 43 subjects, higher initial NIH stroke scale (NIHSS) score (P = 0.005), early increment of sTREM2 (P < 0.001), and late decrement of sTREM2 (P = 0.002), were more common in patients with poor outcome. Based on multivariate analysis, initial NIHSS score (P = 0.015) and early increment of sTREM2 (P = 0.032) were independently associated with poor outcome. The results from the present study indicate that increment of sTREM2 level at the early phase was a predictor of poor outcome. Serial follow-up of sTREM2 may aid prognosis after stroke.
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http://dx.doi.org/10.1016/j.jocn.2020.02.016DOI Listing
March 2020

Global Outcome Assessment Life-long after stroke in young adults initiative-the GOAL initiative: study protocol and rationale of a multicentre retrospective individual patient data meta-analysis.

BMJ Open 2019 11 14;9(11):e031144. Epub 2019 Nov 14.

Neurology Department, University of Maryland School of Medicine, Baltimore, Maryland, USA.

Introduction: Worldwide, 2 million patients aged 18-50 years suffer a stroke each year, and this number is increasing. Knowledge about global distribution of risk factors and aetiologies, and information about prognosis and optimal secondary prevention in young stroke patients are limited. This limits evidence-based treatment and hampers the provision of appropriate information regarding the causes of stroke, risk factors and prognosis of young stroke patients.

Methods And Analysis: The Global Outcome Assessment Life-long after stroke in young adults (GOAL) initiative aims to perform a global individual patient data meta-analysis with existing data from young stroke cohorts worldwide. All patients aged 18-50 years with ischaemic stroke or intracerebral haemorrhage will be included. Outcomes will be the distribution of stroke aetiology and (vascular) risk factors, functional outcome after stroke, risk of recurrent vascular events and death and finally the use of secondary prevention. Subgroup analyses will be made based on age, gender, aetiology, ethnicity and climate of residence.

Ethics And Dissemination: Ethical approval for the GOAL study has already been obtained from the Medical Review Ethics Committee region Arnhem-Nijmegen. Additionally and when necessary, approval will also be obtained from national or local institutional review boards in the participating centres. When needed, a standardised data transfer agreement will be provided for participating centres. We plan dissemination of our results in peer-reviewed international scientific journals and through conference presentations. We expect that the results of this unique study will lead to better understanding of worldwide differences in risk factors, causes and outcome of young stroke patients.
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http://dx.doi.org/10.1136/bmjopen-2019-031144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6887075PMC
November 2019

Deep learning-based optical field screening for robust optical diffraction tomography.

Sci Rep 2019 10 23;9(1):15239. Epub 2019 Oct 23.

Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), 34141, Daejeon, Republic of Korea.

In tomographic reconstruction, the image quality of the reconstructed images can be significantly degraded by defects in the measured two-dimensional (2D) raw image data. Despite the importance of screening defective 2D images for robust tomographic reconstruction, manual inspection and rule-based automation suffer from low-throughput and insufficient accuracy, respectively. Here, we present deep learning-enabled quality control for holographic data to produce robust and high-throughput optical diffraction tomography (ODT). The key idea is to distil the knowledge of an expert into a deep convolutional neural network. We built an extensive database of optical field images with clean/noisy annotations, and then trained a binary-classification network based upon the data. The trained network outperformed visual inspection by non-expert users and a widely used rule-based algorithm, with >90% test accuracy. Subsequently, we confirmed that the superior screening performance significantly improved the tomogram quality. To further confirm the trained model's performance and generalisability, we evaluated it on unseen biological cell data obtained with a setup that was not used to generate the training dataset. Lastly, we interpreted the trained model using various visualisation techniques that provided the saliency map underlying each model inference. We envision the proposed network would a powerful lightweight module in the tomographic reconstruction pipeline.
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http://dx.doi.org/10.1038/s41598-019-51363-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6811526PMC
October 2019

Distal versus Proximal Middle Cerebral Artery Occlusion: Different Mechanisms.

Cerebrovasc Dis 2019 18;47(5-6):238-244. Epub 2019 Jun 18.

Department of Neurology, Kyung Hee University Hospital, Seoul, Republic of Korea.

Background: Clinical and radiological characteristics of middle cerebral artery (MCA) infarction may differ according to the location of occlusion.

Objectives: We investigated the difference between proximal and distal symptomatic MCA occlusion (MCAO) in patients with ischemic stroke. The factors associated with the imaging characteristics were also analyzed.

Methods: Patients with ischemic stroke due to MCAO were consecutively enrolled. The location of MCAO was determined by the ratio of the length of the ipsilesional MCA to that of the contralateral MCA and dichotomized to proximal and distal MCAO. Clinical and radiological characteristics were compared between patients with proximal and distal MCAO. Factors associated with the basal ganglia (BG) involvement, hemorrhagic transformation (HT), and neurological change during admission were investigated.

Results: Among 181 included patients, MCAO location showed a bimodal peak (at the proximal [n = 99] and distal MCA [n = 82]). Proximal MCAO was more frequently associated with hyperlipidemia and large artery atherosclerosis, whereas distal MCAO was more frequently associated with hypertension, atrial fibrillation, and cardioembolic stroke. BG involvement was similar between the 2 groups (48 vs. 39%; p = 0.21), whereas HT was more frequent in distal MCAO (10 vs. 23%; p = 0.02). Among patients with proximal MCAO, hyperintense vessel sign was less frequently observed in those with a BG involvement than those without (38 vs. 60%; p = 0.03). Among those without BG involvement, the presence of HT was very low and similar between patients with proximal and distal MCAOs (1.9 vs. 2.0%). However, in patients with BG involvement, HT was more frequently observed in those with distal MCAO than in those with proximal MCAO (54.8 vs. 15.7%; p < 0.001). The presence of hyperintense vessel sign (OR 0.172, 95% CI 0.051-0.586; p = 0.005) and distal MCAO (OR 0.200, 95% CI 0.059-0.683; p = 0.011) was independently associated with improvement during admission.

Conclusion: Proximal MCAO is more frequently associated with atherosclerosis, whereas distal MCAO is more frequently associated with cardioembolism. In proximal MCAO, the status of collateral flow presented by hyperintense vessel sign may affect the involvement of BG. In distal MCAO, distal migration of the embolus, which first impacted at the proximal MCA causing BG ischemia, may explain the high rate of HT by reperfusion injury. Hyperintense vessel sign and distal MCAO were independently associated with neurological improvement during admission.
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http://dx.doi.org/10.1159/000500947DOI Listing
May 2020

Asymptomatic Basilar Artery Plaque Distribution and Vascular Geometry.

J Atheroscler Thromb 2019 Nov 27;26(11):1007-1014. Epub 2019 Mar 27.

Department of Radiology, Hanyang University Hospital.

Aim: Development of atherosclerotic plaques is affected by vascular geometry and hemodynamics. Hemodynamics in the basilar artery (BA) is unique as the flow converges from vertebral arteries (VAs). Here, we investigated the characteristics of BA plaque based on VA and BA geometry.

Methods: Consecutive patients evaluated using high-resolution magnetic resonance imaging (MRI) at a general health center were screened. Geometric characteristics of VA (VA dominancy and VA-BA angles) and BA (BA convexity and BA angles) were assessed. The burden of BA plaques was investigated in each wall (anterior, posterior, left, and right lateral). The characteristics of BA plaques were compared according to VA dominancy (right vs. left), BA angle of lateral view (lateral mid-BA angle; dichotomized), and total plaque burden (divided by tertiles).

Results: Of the 1029 subjects, BA plaques were observed in 98 (9.5%) patients, and were more frequently located at the anterior wall (32.4%) and posterior wall (35.0%) than the right wall (15.3%) and left lateral wall (17.6%). Right and left lateral plaques were more frequent in the left and right convex BA, respectively (p=0.009 and p=0.024, respectively). Anterior plaques were more frequently observed in low lateral mid-BA angle (p= 0.043). BA plaques were predominant in anterior and posterior walls in patients with lower plaque burden, whereas they were predominant in right and left lateral walls in patients with higher plaque burden (p=0.001 and p=0.025, respectively).

Conclusions: Asymptomatic BA plaque location was associated with BA convexity and lateral mid-BA angle. The anteriorly and posteriorly located BA plaques may extend to the lateral walls as the plaque burden increases.
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http://dx.doi.org/10.5551/jat.47365DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6845693PMC
November 2019

Cycle-consistent deep learning approach to coherent noise reduction in optical diffraction tomography.

Opt Express 2019 Feb;27(4):4927-4943

We present a deep neural network to reduce coherent noise in three-dimensional quantitative phase imaging. Inspired by the cycle generative adversarial network, the denoising network was trained to learn a transform between two image domains: clean and noisy refractive index tomograms. The unique feature of this network, distinct from previous machine learning approaches employed in the optical imaging problem, is that it uses unpaired images. The learned network quantitatively demonstrated its performance and generalization capability through denoising experiments of various samples. We concluded by applying our technique to reduce the temporally changing noise emerging from focal drift in time-lapse imaging of biological cells. This reduction cannot be performed using other optical methods for denoising.
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http://dx.doi.org/10.1364/OE.27.004927DOI Listing
February 2019

Label-Free Identification of Lymphocyte Subtypes Using Three-Dimensional Quantitative Phase Imaging and Machine Learning.

J Vis Exp 2018 11 19(141). Epub 2018 Nov 19.

Department of Physics, Korea Advanced Institute of Science and Technology; KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology; Tomocube, Inc.;

We describe here a protocol for the label-free identification of lymphocyte subtypes using quantitative phase imaging and machine learning. Identification of lymphocyte subtypes is important for the study of immunology as well as diagnosis and treatment of various diseases. Currently, standard methods for classifying lymphocyte types rely on labeling specific membrane proteins via antigen-antibody reactions. However, these labeling techniques carry the potential risks of altering cellular functions. The protocol described here overcomes these challenges by exploiting intrinsic optical contrasts measured by 3D quantitative phase imaging and a machine learning algorithm. Measurement of 3D refractive index (RI) tomograms of lymphocytes provides quantitative information about 3D morphology and phenotypes of individual cells. The biophysical parameters extracted from the measured 3D RI tomograms are then quantitatively analyzed with a machine learning algorithm, enabling label-free identification of lymphocyte types at a single-cell level. We measure the 3D RI tomograms of B, CD4+ T, and CD8+ T lymphocytes and identified their cell types with over 80% accuracy. In this protocol, we describe the detailed steps for lymphocyte isolation, 3D quantitative phase imaging, and machine learning for identifying lymphocyte types.
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http://dx.doi.org/10.3791/58305DOI Listing
November 2018

Relationship between cerebral microbleeds and white matter MR hyperintensities in systemic lupus erythematosus: a retrospective observational study.

Neuroradiology 2019 Mar 10;61(3):265-274. Epub 2018 Nov 10.

Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.

Purpose: White matter hyperintensities (WMH) and cerebral microbleeds (CMBs) are known to be associated with small vessel diseases (SVD) and neuroinflammation. The purpose was to investigate the relationship between CMBs and WMH in patients with systemic lupus erythematosus (SLE).

Methods: Thirty-one SLE patients with WMH and 27 SLE patients with normal brain MRI were compared. The presence, location, and grading of CMBs were assessed using susceptibility-weighted images. WMH volume was quantitatively measured. Clinical characteristics and serologic markers were compared. We also performed two separate subgroup analyses after (1) dividing WMH into inflammatory lesion vs. SVD subgroups and (2) dividing WMH into those with vs. without CMB subgroups.

Results: The WMH group showed more frequent CMBs than the normal MR group (p < 0.001). The WMH group showed higher SLE disease activity index, longer disease duration, and a higher incidence of antiphospholipid syndrome than the normal MR group (p = 0.02, 0.04, and 0.04, respectively). There was a moderate correlation between WMH volume and CMB grading (r = 0.49, p = 0.006). Within the WMH group, the inflammatory lesion subgroup showed more frequent CMBs and larger WMH volume than the SVD subgroup (p < 0.001 and 0.02, respectively). The WMH with CMB subgroup had larger WMH volume than the WMH without CMB subgroup (p = 0.004).

Conclusion: In patients with SLE, CMBs could be related to large-volume WMH and inflammatory lesions. CMBs along with severe WMH could be used as an imaging biomarker of vasculitis in patients with SLE.
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http://dx.doi.org/10.1007/s00234-018-2130-1DOI Listing
March 2019

Combining Three-Dimensional Quantitative Phase Imaging and Fluorescence Microscopy for the Study of Cell Pathophysiology.

Yale J Biol Med 2018 09 21;91(3):267-277. Epub 2018 Sep 21.

Tomocube Inc., Daejeon, Republic of Korea.

Quantitative phase imaging (QPI) has emerged as one of the powerful imaging tools for the study of live cells in a non-invasive manner. In particular, multimodal approaches combining QPI and fluorescence microscopic techniques have been recently developed for superior spatiotemporal resolution as well as high molecular specificity. In this review, we briefly summarize recent advances in three-dimensional QPI combined with fluorescence techniques for the correlative study of cell pathophysiology. Through this review, biologists and clinicians can be provided with insights on this rapidly growing field of research and may find broader applications to investigate unrevealed nature in cell physiology and related diseases.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6153632PMC
September 2018

Regulatory T cells increase after treatment with poly (ADP-ribose) polymerase-1 inhibitor in ischemic stroke patients.

Int Immunopharmacol 2018 Jul 27;60:104-110. Epub 2018 Apr 27.

Department of Neurology, College of Medicine, Hanyang University, Seoul, Republic of Korea. Electronic address:

Background: Regulatory T cells (Tregs) are thought to play a modulatory role in immune responses and to improve outcomes after ischemic stroke. Thus, various strategies for increasing Tregs in animal models of ischemic stroke have yielded successful results. The aim of this study was to examine the potential effect of poly (ADP-ribose) polymerase-1 (PARP-1) inhibitor on Treg proportion in stroke patients.

Methods: Peripheral blood samples were collected from 12 ischemic stroke patients (within 72 h of stroke onset) and 5 healthy control subjects. Flow cytometry analyses and quantitative reverse transcription polymerase chain reactions (qRT-PCR) were performed on peripheral blood mononuclear cells (PBMCs) before and after treating them with PARP-1 inhibitor (3-AB; JPI-289 1 μm, JPI-289 10 μm) for 24 h.

Results: Treg proportions were significantly higher in healthy controls (median 2.8%, IQR 2.6-5.0%) than ischemic stroke patients (median 1.6%, IQR 1.25-2.2%) (p < 0.001). In the latter, Treg proportions were positively correlated with age (r = 0.595, p = 0.041), but not with infarct volume (r = 0.367, p = 0.241). After PARP-1 inhibitor treatment, Treg proportions among PBMCs increased in response to high dose (10 μm) JPI-289 (median 2.3%, IQR 2.0-2.9%) as did Treg-associated transcription factors such as FoxP3 and CTLA-4 mRNA. PARP-1 inhibitor treatment also decreased pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-17) and increased anti-inflammatory cytokines (IL-4, IL-10, and TGF-β1).

Conclusion: Treg proportions are reduced in ischemic stroke patients and increased by treatment with high-dose PARP-1 inhibitor JPI-289. The PARP-1 inhibitor also had a possible anti-inflammatory effect on cytokine levels, and may ameliorate the outcome of ischemic stroke by up-regulating Tregs.
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http://dx.doi.org/10.1016/j.intimp.2018.04.043DOI Listing
July 2018

Differences between the Molecular Mechanisms Underlying Ruptured and Non-Ruptured Carotid Plaques, and the Significance of ABCA1.

J Stroke 2018 Jan 31;20(1):80-91. Epub 2018 Jan 31.

Department of Neurology, Kyung Hee University School of Medicine, Seoul, Korea.

Background And Purpose: Carotid plaques are a strong risk factor for ischemic stroke, and plaque rupture poses an even higher risk. Although many studies have investigated the pathogenic mechanisms of carotid plaque formation, few have studied the differences in molecular mechanisms underlying the rupture and non-rupture of carotid plaques. In addition, since early diagnosis and treatment of carotid plaque rupture are critical for the prevention of ischemic stroke, many studies have sought to identify the important target molecules involved in the rupture. However, a target molecule critical in symptomatic ruptured plaques is yet to be identified.

Methods: A total of 79 carotid plaques were consecutively collected, and microscopically divided into ruptured and non-ruptured groups. Quantitative polymerase chain reaction array, proteomics, and immunohistochemistry were performed to compare the differences in molecular mechanisms between ruptured and non-ruptured plaques. Enzyme-linked immunosorbent assay was used to measure the differences in ATP-binding cassette subfamily A member 1 (ABCA1) levels in the serum.

Results: The expression of several mRNAs and proteins, including ABCA1, was higher in ruptured plaques than non-ruptured plaques. In contrast, the expression of other proteins, including β-actin, was lower in ruptured plaques than non-ruptured plaques. The increased expression of ABCA1 was consistent across several experiments, ABCA1 was positive only in the serum of patients with symptomatic ruptured plaques.

Conclusions: This study introduces a plausible molecular mechanism underlying carotid plaque rupture, suggesting that ABCA1 plays a role in symptomatic rupture. Further study of ABCA1 is needed to confirm this hypothesis.
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http://dx.doi.org/10.5853/jos.2017.02390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5836578PMC
January 2018

Basilar Artery Plaque and Pontine Infarction Location and Vascular Geometry.

J Stroke 2018 Jan 31;20(1):92-98. Epub 2018 Jan 31.

Department of Neurology, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, Korea.

Background And Purpose: Subclinical atherosclerotic plaques are common in patients with pontine infarctions (PIs) but without basilar artery (BA) stenosis. We hypothesized that BA plaque locations may differ by PI type and vertical location as well as vertebrobasilar artery geometry.

Methods: Ninety-six patients with PI but without BA stenosis on magnetic resonance imaging (MRI) and magnetic resonance angiography were enrolled. PIs were classified by type (paramedian, deep, or lateral) and vertical location (rostral, middle, or caudal). Patients underwent high-resolution MRI to evaluate BA plaque location (anterior, posterior, or lateral). The mid-BA angle on anteroposterior view and angle between the BA and dominant vertebral artery (BA-VA angle) on lateral view were measured.

Results: The PIs were paramedian (72.9%), deep (17.7%), and lateral (9.4%) type with a rostral (32.3%), middle (42.7%), and caudal (25.0%) vertical location. The BA plaque locations differed by PI type (=0.03) and vertical location (<0.001); BA plaques were most frequent at the posterior wall in paramedian (37.1%) and caudal (58.3%) PIs and at the lateral wall in lateral (55.5%) and middle (34.1%) PIs. The BA-VA and mid-BA angles differed by BA plaque and PI vertical location; the greatest BA-VA angle was observed in patients with posterior plaques (<0.001) and caudal PIs (<0.001). Greatest mid-BA angles were observed with lateral BA plaques (=0.03) and middlelocated PIs (=0.03).

Conclusions: Greater mid-BA angulation may enhance lateral plaque formation, causing lateral and middle PIs, whereas greater BA-VA angulation may enhance posterior plaque formation, causing paramedian or caudal PIs.
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http://dx.doi.org/10.5853/jos.2017.00829DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5836573PMC
January 2018

Early Treatment with Poly(ADP-Ribose) Polymerase-1 Inhibitor (JPI-289) Reduces Infarct Volume and Improves Long-Term Behavior in an Animal Model of Ischemic Stroke.

Mol Neurobiol 2018 Sep 30;55(9):7153-7163. Epub 2018 Jan 30.

Department of Neurology, College of Medicine, Hanyang University, 222-1 Wangsimniro, Seongdong-gu, Seoul, 04763, Republic of Korea.

In patients with stroke and neurodegenerative diseases, overactivation of poly(ADP-ribose) polymerase-1 (PARP-1) causes harmful effects by inducing apoptosis, necrosis, neuroinflammation, and immune dysregulation. The current study investigated the neuroprotective effect of a novel PARP-1 inhibitor, JPI-289, in an animal model of ischemic stroke. A transient middle cerebral artery occlusion (tMCAO, 2 h) model was used to determine the therapeutic effect and the most effective dose and time window of administration of JPI-289. We also investigated the long-term outcomes of treatment with JPI-289 by diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) MRI and by measuring neurological function at 24 h, 7 days, and 28 days after MCAO. The most effective dose and time window of administration of JPI-289 was 10 mg/kg administered 2 h after MCAO with reperfusion. Twenty-four hours after MCAO, infarct volume was reduced by 53% and the number of apoptotic cells was reduced by 56% compared with control. JPI-289 also reduced infarct volume by 16% in the permanent MCAO model. In an MRI-based study, initial infarct volume, as measured using DWI, was similar in the control and JPI-289-treated groups. However, infarct volume and brain swelling were significantly reduced in the group treated with JPI-289 (2 h) at 24 h and 7 days after MCAO. Neurological functions also improved in the group treated with JPI-289 (2 h) until 28 days after MCAO. Inhibition of PARP-1 has neuroprotective effects (reduction of infarct volume and brain swelling) in both tMCAO and pMCAO models of ischemic stroke.
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http://dx.doi.org/10.1007/s12035-018-0910-6DOI Listing
September 2018

Quantitative susceptibility mapping of the motor cortex: a comparison of susceptibility among patients with amyotrophic lateral sclerosis, cerebrovascular disease, and healthy controls.

Neuroradiology 2017 Dec 11;59(12):1213-1222. Epub 2017 Oct 11.

Department of Neurology, Hanyang University Hospital, Hanyang University College of Medicine, Seoul, Korea.

Purpose: The purpose of this study was to investigate the differences in motor cortex susceptibility among patients with amyotrophic lateral sclerosis (ALS), cerebrovascular disease (CVD), and healthy controls using quantitative susceptibility mapping (QSM).

Methods: We retrospectively reviewed 78 QSM images from 26 patients with ALS, 26 age- and sex-matched patients with CVD, and 26 healthy controls. A region of interest was drawn in the hand lobule of both the motor cortexes and subcortical white matter. The relative susceptibility (RS) of the motor cortex was obtained by subtracting the susceptibility of the subcortical white matter from that of the motor cortex. We compared the cortex, cortex, subcortical white matter, RS, and RS values among the three groups using analysis of variance and Tukey's post hoc test. Receiver operating characteristic (ROC) curve analysis was also performed.

Results: There were significant differences in the cortex, cortex, RS, and RS among the three groups, with higher values in patients with ALS (p = 0.01, p = 0.004, p < 0.001, and p < 0.001, respectively). Subcortical white matter was significantly lower in patients with ALS compared with patients with CVD and healthy controls (p = 0.04). ROC curve analysis showed that the area under the curve of RS was 0.70, the highest among the measured parameters.

Conclusion: Quantitative measurements of susceptibility of the motor cortex with QSM demonstrate its potential as an imaging biomarker in ALS patients.
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http://dx.doi.org/10.1007/s00234-017-1933-9DOI Listing
December 2017

Range of glucose as a glycemic variability and 3-month outcome in diabetic patients with acute ischemic stroke.

PLoS One 2017 7;12(9):e0183894. Epub 2017 Sep 7.

Department of Neurology, Seoul National University Hospital, Seoul, Republic of Korea.

Glycemic variability (GV) is reportedly a predictor for poor outcome in various clinical conditions. We aimed to assess whether GV during hospital admission is associated with poor outcomes in patients with acute ischemic stroke (AIS) and diabetes. We prospectively enrolled consecutive patients with AIS from the registry of 6 tertiary hospitals between January 2013 and December 2014. For the GV index, we used a glucose level range that was divided into 4 quartiles. Multivariable binary and ordinal logistic regression analyses were performed to determine the association between GV and the modified Rankin Scale score (3-6) at 3 months. We enrolled 1,504 patients with AIS and diabetes (mean age, 68.1 years; male, 57.2%), of which 35.1% had poor outcomes at 3 months. An increasing glucose range quartile was positively associated with initial neurologic severity and development of hypoglycemia during hospital admission. Multivariable analysis showed that the glucose level range quartile was associated with poor outcomes, even after adjusting for the number of glucose measurement and hypoglycemia (odds ratio [OR] Q2 vs. Q1: 1.50, 95% confidence interval [CI]: 1.02-2.18; OR Q3 vs. Q1: 2.01, 95% CI: 1.34-3.01; OR Q4 vs. Q1: 1.98, 95% CI: 1.22-3.23). These associations remained significant after dichotomization according to glycated hemoglobin levels at admission. An increasing glucose level range as a GV index during hospital admission was associated with poor functional outcomes at 3 months in patients with AIS and diabetes.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0183894PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5589173PMC
October 2017

Association between nocturnal blood pressure variation and wake-up ischemic stroke.

J Clin Neurosci 2017 Oct 19;44:210-213. Epub 2017 Jul 19.

Department of Neurology, College of Medicine, Hanyang University, Seoul, Republic of Korea. Electronic address:

Ischemic stroke during nocturnal sleep, known as wake-up stroke (WUS), has been reported to have more severe symptoms and worse outcomes than non-WUS. However, studies on risk factors for WUS are scarce and the association between nocturnal blood pressure (BP) and WUS is unclear. In this study, we used ambulatory blood pressure monitoring (ABPM) to examine the association between WUS and variation in nocturnal BP. A total of 369 patients with ischemic stroke within one week were consecutively enrolled. ABPM was applied 1-2weeks after the ictus because of possible reactive increments of BP; antihypertensive medications were delayed until ABPM. Patients were classified into two groups: WUS and non-WUS. Clinical characteristics, including ABPM parameters, were compared. Sixty-seven (18%) patients had WUS. In univariate analysis, patients with WUS had more severe stroke symptoms than patients with non-WUS. There were no differences in clinical characteristics. In addition, ABPM parameters, including nocturnal BP dipping and morning BP surge, were not associated with occurrence of WUS. Patients with WUS had more severe stroke symptoms and worse outcomes than those with non-WUS. Variation in nocturnal BP may not associated with the occurrence of WUS.
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http://dx.doi.org/10.1016/j.jocn.2017.06.066DOI Listing
October 2017

Analysis of the Expectation of Stem Cell Therapy in Patients with Alzheimer's Disease.

Dement Neurocogn Disord 2016 Dec 31;15(4):129-134. Epub 2016 Dec 31.

Department of Neurology, Hanyang University College of Medicine, Seoul, Korea.

Background And Purpose: Alzheimer's disease (AD) is the most common form of dementia which typically manifests as loss of memory and cognitive functions. Currently, available treatments for AD provide only symptomatic improvement and the benefit is minimal. Stem cell therapy (SCT) has been considered a promising treatment option for AD. We investigated the caregiver's perception about implementation of SCT in their AD patients, and determined the factors related to SCT.

Methods: A total of 100 caregivers, who cared for their AD patients, were interviewed at two hospitals. Structured open and closed questions about SCT for AD were asked by trained interviewers using the conventional in-person method. In addition, 60 dementia-related physicians were randomly interviewed via an e-mail questionnaire.

Results: Of the 100 subjects, 61 caregivers replied that they wanted their AD patients to receive SCT. Approximately 50% of the caregivers expected high improvement in cognitive function, behavioral and psychological symptoms, and activities of daily living, and physical improvements among their AD patients. However, physicians had much lower expectations of improvements in the above parameters. Multi-variate analysis revealed that female gender [odds ratio (OR): 3.747, 95% confidence interval (CI): 1.425-9.851] and familiarity with stem cells (OR: 3.873, 95% CI: 1.290-11.622) were independently associated with caregivers' desire that their AD patients should undergo SCT. The major source of information on SCT was television (76.7%), and the most reliable source of information on SCT was physicians (83.6%).

Conclusions: In this study, many caregivers of AD patients fantasized and overestimated the need for SCT in comparison with physicians' expectation. Therefore, it is necessary for physicians to develop strategies for educating caregivers about the appropriate risks and benefits of SCT.
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http://dx.doi.org/10.12779/dnd.2016.15.4.129DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6428014PMC
December 2016

Early Activation of Phosphatidylinositol 3-Kinase after Ischemic Stroke Reduces Infarct Volume and Improves Long-Term Behavior.

Mol Neurobiol 2017 09 2;54(7):5375-5384. Epub 2016 Sep 2.

Department of Neurology, Hanyang University College of Medicine, Seoul, South Korea.

Phosphatidylinositol 3-kinases (PI3Ks) have recently been implicated in apoptosis and ischemic cell death. We tested the efficacy of early intervention with a peptide PI3K activator in focal cerebral ischemia. After determining the most effective dose (24 μg/kg) and time window (2 h after MCAO) of treatment, a total of 48 rats were subjected to middle cerebral artery occlusion (MCAO). Diffusion weighted MRI (DWI) was performed 1 h after MCAO and rats with lesion sizes within a predetermined range were randomized to either PI3K activator or vehicle treatment arms. Fluid attenuated inversion recovery (FLAIR) MRI, neurological function, western blots, and immunohistochemistry were blindly assessed. Initial DWI lesion volumes were nearly identical between two groups prior to treatment. However, FLAIR showed significantly smaller infarct volumes in the PI3K activator group compared with vehicle (146 ± 81 mm and 211 ± 96 mm, p = 0.045) at 48 h. The PI3K activator group also had better neurological function for up to 2 weeks. In addition, PI3K activator decreased the number of TUNEL-positive cells in the peri-infarct region compared with the control group. Western blot and immunohistochemistry showed increased expression of phosphorylated Akt (Ser473) and GSK-3β (Ser9) and decreased expression of cleaved caspase-9 and caspase-3. Our results suggest a neuroprotective role of early activation of PI3K in ischemic stroke. The use of DWI in the randomization of experimental groups may reduce bias.
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http://dx.doi.org/10.1007/s12035-016-0063-4DOI Listing
September 2017

Non-aneurysmal subarachnoid hemorrhage in two patients with systemic lupus erythematosus: Case reports and literature review.

Int J Rheum Dis 2018 Mar 25;21(3):761-766. Epub 2016 Jul 25.

Department of Radiology, Hanyang University College of Medicine, Hanyang University Hospital, Seoul, South Korea.

We describe two cases of non-aneurysmal subarachnoid hemorrhage (SAH) and multifocal stenosis of the intracranial arteries. The patients' histories together with magnetic resonance angiography, vessel wall imaging and transcranial Doppler (TCD) indicated that the SAH was due to vasculitis or reversible cerebral vasoconstriction syndrome (RCVS). Differential diagnosis of vasculitis and RCVS is important because the treatment strategies are different: immunosuppressants in vasculitis and calcium channel blockers in RCVS. Vessel wall magnetic resonance imaging and TCD can be helpful in differentiating them.
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http://dx.doi.org/10.1111/1756-185X.12867DOI Listing
March 2018