Exosome-Based Delivery of miR-124 in a Huntington’s Disease Model

Lee, Soon-Tae,Im, Wooseok,Ban, Jae-Jun,Lee, Mijung,Jung, Keun-Hwa,Lee, Sang Kun,Chu, Kon,Kim, Manho The Korean Movement Disorder Society 2017 Journal of movement disorders: official journal of Vol.10 No.1

<P><B>Objective </B></P><P>Huntington’s disease (HD) is a genetic neurodegenerative disease that is caused by abnormal CAG expansion. Altered microRNA (miRNA) expression also causes abnormal gene regulation in this neurodegenerative disease. The delivery of abnormally downregulated miRNAs might restore normal gene regulation and have a therapeutic effect. </P><P><B>Methods </B></P><P>We developed an exosome-based delivery method to treat this neurodegenerative disease. miR-124, one of the key miRNAs that is repressed in HD, was stably overexpressed in a stable cell line. Exosomes were then harvested from these cells using an optimized protocol. The exosomes (Exo-124) exhibited a high level of miR-124 expression and were taken up by recipient cells. </P><P><B>Results </B></P><P>When Exo-124 was injected into the striatum of R6/2 transgenic HD mice, expression of the target gene, RE1-Silencing Transcription Factor, was reduced. However, Exo-124 treatment did not produce significant behavioral improvement. </P><P><B>Conclusion </B></P><P>This study serves as a proof of concept for exosome-based delivery of miRNA in neurodegenerative diseases.</P>

The Effects of Proprioceptor Training and Vestibular Organ Training on Balance Ability of Adults

Sang Bin Lee,Ok Kon Moon,Jung Hyun Choi,Ho Jung An,Hee Joon Shin,Nyeon Jun Kim,Si Eun Park,Young Hwa Song,Kyung Ok Min 국제물리치료학회 2014 Journal of International Academy of Physical Ther Vol.5 No.1

The purpose of this study was to analysis of the effect of proprioceptor training and vestibular organ training for balance ability. The subjects was consist of two different subjects group, proprioceptor training group and vestibular organ training group. Proprioceptor training group consisted of 10 subjects and vestibular organ training group consisted of 10 subjects. Training was performed 3 times per week, 30 minutes per day, for 3 weeks. Balance ability analysis was performed using Romberg's one leg standing test and BT4 when opened eyes and closed eyes. The analysis results were as follows. There was no significant differences in balance after the training in both groups when they opened their eyes(p<.05). But there was significant differences in balance after the training in both groups when they closed their eyes(p<.05). And there was no significant difference in balance after the training between the proprioceptor training group and the vestibular organ training group when they closed their eyes(p<.05). Given the above results, proprioceptor training and vestibular organ training enhanced balance but there was no significant difference between the two methods.

What Kind of Job Characteristics are Important for Improving Students' Competencies in Co-op Education : KoreaTech IPP Case

Lee, Ji-young,Lee, Sang-kon,Lee, Ji-yeon Korean Institute for Pratical Engineering Educatio 2019 실천공학교육논문지 Vol.11 No.2

The purpose of this study was to examine the effect of on-site training environments and goals on learning outcomes of trainees. For this purpose, the study analyzed survey data collected from 752 students who participated in KOREATECH's Industry Professional Practice (IPP) on-site training program from 2017 to 2018. The following summarizes some important findings from the study results: First, on examining whether the effect of job characteristics on the academic competencies differs according to the characteristics of the group, it was found that the factors that affect the whole group were job content, coaching, and welfare benefits, but the effect of job scope was statistically significant. Second, on examining whether the effect of job characteristics on job competencies differs according to the characteristics of the group, it was found that the factors that affect the whole group were job content, coaching, and job scope, but the effect of welfare was statistically significant. Analyzing by training goals, it was found that the major influencers were job content in the Recruitment-intended group; and job content, coaching and job scope in the Training-intended group. Based on the results, the implications of the study and follow-up studies are suggested.

Association of Cardiac Hemodynamic Factors With Severity of White Matter Hyperintensities in Chronic Valvular Heart Disease

Lee, Woo-Jin,Jung, Keun-Hwa,Ryu, Young Jin,Kim, Jeong-Min,Lee, Soon-Tae,Chu, Kon,Kim, Manho,Lee, Sang Kun,Roh, Jae-Kyu American Medical Association 2018 JAMA neurology Vol.75 No.1

<P>CONCLUSIONS AND RELEVANCE Mean RA pressure was independently associated with the WMH volume in chronic valvular heart disease. Chronically altered RA hemodynamics might have a distinct influence on the pathomechanism underlying the development of WMH.</P>

Cerebral mapping of glutamate using chemical exchange saturation transfer imaging in a rat model of stress‐induced sleep disturbance at 7.0T

Lee, Dong‐,Hoon,Woo, Chul‐,Woong,Kwon, Jae‐,Im,Chae, Yeon Ji,Ham, Su Jung,Suh, Ji‐,Yeon,Kim, Sang‐,Tae,Kim, Jeong Kon,Kim, Kyung Won,Woo, Dong‐,Cheol,Lee, Do‐ John WileySons, Inc. 2019 Journal of magnetic resonance imaging Vol.50 No.6

<P><B>Background</B></P><P>Glutamate chemical exchange saturation transfer (GluCEST) imaging has been widely used in brain psychiatric disorders. Glutamate signal changes may help to evaluate the sleep‐related disorders, and could be useful in diagnosis.</P><P><B>Purpose</B></P><P>To evaluate signal changes in the hippocampus and cortex of a rat model of stress‐induced sleep disturbance using GluCEST.</P><P><B>Study Type</B></P><P>Prospective animal study.</P><P><B>Animal Model</B></P><P>Fourteen male Sprague–Dawley rats.</P><P><B>Field Strength/Sequence</B></P><P>7.0T small bore MRI / fat‐suppressed, turbo‐rapid acquisition with relaxation enhancement (RARE) for CEST, and spin‐echo, point‐resolved proton MR spectroscopy (<SUP>1</SUP>H MRS).</P><P><B>Assessment</B></P><P>Rats were divided into two groups: the stress‐induced sleep‐disturbance group (SSD, <I>n</I> = 7) and the control group (CTRL, <I>n</I> = 7), to evaluate and compare the cerebral glutamate signal changes. GluCEST data were quantified using a conventional magnetization transfer ratio asymmetry in the left‐ and right‐side hippocampus and cortex. The correlation between GluCEST signal and glutamate concentrations, derived from <SUP>1</SUP>H MRS, was evaluated.</P><P><B>Statistical Analysis</B></P><P>Wilcoxon rank‐sum test between CEST signals and multiparametric MR signals, Wilcoxon signed‐rank test between CEST signals on the left and right hemispheres, and a correlation test between CEST signals and glutamate concentrations derived from <SUP>1</SUP>H MRS.</P><P><B>Results</B></P><P>Measured GluCEST signals showed significant differences between the two groups (left hippocampus; 4.23 ± 0.27% / 5.27 ± 0.42% [SSD / CTRL, <I>P</I> = 0.002], right hippocampus; 4.50 ± 0.44% / 5.04 ± 0.34% [<I>P</I> = 0.035], left cortex; 2.81 ± 0.38% / 3.56 ± 0.41% [<I>P</I> = 0.004], and right cortex; 2.95 ± 0.47% / 3.82 ± 0.26% [<I>P</I> = 0.003]). GluCEST signals showed positive correlation with glutamate concentrations (R<SUP>2</SUP> = 0.312; <I>P</I> = 0.038).</P><P><B>Data Conclusion</B></P><P>GluCEST allowed the visualization of cerebral glutamate changes in rats subjected to sleep disturbance, and may yield valuable insights for interpreting alterations in cerebral biochemical information.</P><P><B>Level of Evidence:</B> 2</P><P><B>Technical Efficacy:</B> Stage 2</P><P>J. Magn. Reson. Imaging 2019;50:1866–1872.</P>

Physicochemical changes caused by reactive MgO in alkali-activated fly ash/slag blends under accelerated carbonation

Lee, Nam Kon,Koh, Kyung Taek,Kim, Min Ook,An, Gi Hong,Ryu, Gum Sung Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.15

<P><B>Abstract</B></P> <P>This study characterizes alkali-activated fly ash/slag (AFS) blends with reactive MgO under an accelerated carbonation condition. XRD, DTG, FT-IR, solid-state <SUP>29</SUP>Si, and <SUP>27</SUP>Al MAS NMR analyses were conducted to investigate the microstructural and gel phase changes caused by the addition of MgO under a high CO<SUB>2</SUB> condition. The addition of reactive MgO to the AFS blends confirmed the formation of a hydrotalcite-like phase with a higher Al uptake level rather than Al substitution for Si in C-S-H gel. The incorporated MgO reacted with CO<SUB>2</SUB> to precipitate as magnesium carbonate and an amorphous hydrotalcite-like phase, which mitigated the carbonation of the C-S-H gel by retarding the penetration of CO<SUB>2</SUB>. The carbonated samples showed the presence of aluminosilicate gel with Q<SUP>3</SUP> and Q<SUP>4</SUP> sites stemming from the decalcification of C-(A-)S-H gel and highly cross-linked C-(N-)A-S-H gel.</P>

Output voltage modulation in triboelectric nanogenerator by printed ion gel capacitors

Lee, Ju Hyun,Park, Yun Sung,Cho, Sunghwan,Kang, In Seok,Kim, Jin Kon,Jeong, Unyong Elsevier 2018 Nano energy Vol.54 No.-

<P><B>Abstract</B></P> <P>The triboelectric nanogenerator (TENG) has been investigated intensively during the last decade in terms of power improvement and application as sensors, however, its voltage is usually too high and spike-like to be used directly as a power source for electronic devices. Although there was an effort to adjust the voltage through the circuit design, the complexity and the bulkiness of the circuit board make it difficult. Here, we propose a simple approach to change the spike-like voltage profiles to square-like profiles and adjust the output voltage to be suitable range for electronics. We used printed ion gel electrolyte patterns as capacitors and investigated the effects of dimension of the capacitor, connection types (serial, parallel) of multiple capacitors, and electrochemical conditions. The voltage profile of the TENG-ion gel system was modulated by the contact frequency applied to the TENG, the contact area of the ion gel with the electrode, the type of ions in the electrolyte, reduction/oxidation reaction in the gel, and the connection type (parallel, series) between ion gel patterns. We successfully demonstrated the light emission of a large number of printed electrochemiluminescence patterns.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Triboelectric voltage profile is modulated by printed ion gel electrolyte patterns. </LI> <LI> Dimension and connection type of the ion gel capacitors determine voltage profiles. </LI> <LI> Self-powered lighting of printed electrochemiluminescence patterns is demonstrated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of occlusal load on the cervical stress distribution : A three-dimensional finite element study

Lee, Hyeong-Mo,Hur, Bock,Kim, Hyeon-Cheol,Woo, Sung-Gwan,Kim, Kwang-Hoon,Son, Kon,Park, Jeong- Kil 대한치과보존학회 2006 Restorative Dentistry & Endodontics Vol.31 No.6

본 연구의 목적은 3차원유한요소분석법을 이용하여 정상 상악 제2소구치의 협측부의 응력분포에 다양한 교합응력이 미치는 영향을 평가하고자 하였다. 상악 제2소구치의 3차원유한요소모델을 형성한 후 형성된 모델에 3종류의 정적인 500N 점하중의 응력조건을 부여하였다. ANSYS 프로그램 (Swanson Analysis Systems, Inc., Houston, USA)으로 최대주응력과 최소주응력을 4개의 수평면 상(CEJ 상방 1mm, CEJ 상방 0.5 mm, CEJ, CEJ 하방 0.5 mm)에서 분석하여 다음 결과를 얻었다. 1. peak stress가 협측 백악법랑경계를 따라 비대칭적인 모습으로 나타났다. 2.압축응력 값은 법랑질의 압축파괴응력 범위 내에 있었지만 인장응력은 법랑질의 인장파괴응력 범위를 넘어섰다. 3. 비우식성치경부병소를 발생시키는 주요인은 설측교두의 협측경사면에 가해지는 교합압에 의한 인장응력이라고 보여진다. The objective of this study was to investigate the effects of various occlusal loads on the stress distribu-tion of the buccal cervical region of a normal maxillary second premolar, using a three dimensional finite element analysis (3D FEA). After 3D FE modeling of maxillary second premolar, a static load of 500N of three load cases was applied. Stress analysis was performed using ANSYS (Swanson Analysis Systems, Inc., Houston, USA). The maxi-mum principal stresses and minimum principal stresses were sampled at thirteen nodal points in the buc-cal cervical enamel for each four horizontal planes 1.0㎜ above CEJ, 0.5 ㎜ above CEJ, CEJ, 0.5 ㎜ under CEJ. The results were as follows 1. The peak stress was seen at the cervical enamel surface of the mesiobuccal line angle area, asymmetri-cally. 2. The values of compressive stresses were within the range of the failure stress of enamel. But the val-ues of tensile stresses exceeded the range of the failure stress of enamel. 3. The tensile stresses from the perpendicular load at the buccal incline of palatal cusp may be shown to be the primary etiological factors of the NCCLs.

Phase Behavior of Poly(2-vinylpyridine)-<i>block</i>-Poly(4-vinylpyridine) Copolymers Containing Gold Nanoparticles

Lee, Jaeyong,Kwak, Jongheon,Choi, Chungryong,Han, Sung Hyun,Kim, Jin Kon American Chemical Society 2017 Macromolecules Vol.50 No.23

<P>We studied the phase behavior of the poly(2-vinylpyridine)-block-poly(4-vinylpyridine) copolymer (P24VP) containing gold nanoparticles, by rheometry, small-angle X-ray scattering, transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). Although both blocks of P24VP exhibited attractive interaction to gold precursors, unusual phase behavior was observed depending on the amount of gold nanoparticles. As the amount of gold nanoparticles increased, the order-to-disorder transition temperature (T-ODT) of P24VP with gold nanoparticles decreased first, then increased, and finally decreased again. To explain this phenomenon, We prepared two block copolymers: polystyrene-block-poly(2-vinylpyridine) copolymer (PS2VP) and polystyrene-block-poly(4-vinylpyridine) copolymer (PS4VP) containing gold nanoparticles. With increasing the amount of gold particles, the T-oDT of PS2VP increased continuously, whereas that of PS4VP gradually decreased. For PS4VP containing gold nanoparticles, because P4VP chains can interact with the gold nanoparticle surface, density fluctuations exist near the gold nanoparticle surfaces, which causes the T-oDT to decrease. On the other hand, although the pyridine ring in P2VP could be associated with the gold surface, P2VP chains become stretched due to steric hindrance arising from the ortho position of nitrogen in P2VP. The chain stretching increases the T-ODT. Thus, the decrease of T-oDT for P24VP originates from P4VP microdomains containing gold nanoparticles, while the increase of T-ODT is attributed to the P2VP microdomains containing, gold nanoparticles. With increasing the amounts of gold nanoparticles, the contribution of P4VP microdomains containing gold nanoparticles on the T-ODT becomes dominant, causing the T-oDT to redecrease. To verify the gold nanoparticle position in both P2VP and P4VP microdomains, we performed TEM and scanning transmission electron microscopy (STEM) experiments. At lower amounts of gold nanoparticles, they are mainly located inside P4VP microdomains. With increasing the amount of the gold nanoparticles, they are distributed in both P2VP and P4VP microdomains, though the amount of gold nanoparticles in P4VP microdomains is larger than that in P2VP microdomains.</P>

Proximity-Directed Labeling Reveals a New Rapamycin-Induced Heterodimer of FKBP25 and FRB in Live Cells

Lee, Song-Yi,Lee, Hakbong,Lee, Hye-Kyeong,Lee, Seung-Won,Ha, Sung Chul,Kwon, Taejoon,Seo, Jeong Kon,Lee, Changwook,Rhee, Hyun-Woo American Chemical Society 2016 ACS central science Vol.2 No.8

<▼1><P/><P>Mammalian target of rapamycin (mTOR) signaling is a core pathway in cellular metabolism, and control of the mTOR pathway by rapamycin shows potential for the treatment of metabolic diseases. In this study, we employed a new proximity biotin-labeling method using promiscuous biotin ligase (pBirA) to identify unknown elements in the rapamycin-induced interactome on the FK506-rapamycin binding (FRB) domain in living cells. FKBP25 showed the strongest biotin labeling by FRB–pBirA in the presence of rapamycin. Immunoprecipitation and immunofluorescence experiments confirmed that endogenous FKBP25 has a rapamycin-induced physical interaction with the FRB domain. Furthermore, the crystal structure of the ternary complex of FRB–rapamycin–FKBP25 was determined at 1.67-Å resolution. In this crystal structure we found that the conformational changes of FRB generate a hole where there is a methionine-rich space, and covalent metalloid coordination was observed at C2085 of FRB located at the bottom of the hole. Our results imply that FKBP25 might have a unique physiological role related to metallomics in mTOR signaling.</P></▼1><▼2><P>A proximity biotin-labeling method revealed that FKBP25 is a strong rapamycin-induced interaction partner of FK506-rapamycin binding (FRB). This interaction was supported by the crystal structure of the ternary complex of FKBP25−rapamycin−FRB.</P></▼2>