95 results on '"Jae-Hoon Kim"'
Search Results
2. Gapless superconductivity in Nb thin films probed by terahertz spectroscopy
- Author
-
Ji Eun Lee, Joonyoung Choi, Taek Sun Jung, Jong Hyuk Kim, Young Jai Choi, Kyung Ik Sim, Younjung Jo, and Jae Hoon Kim
- Subjects
Multidisciplinary ,General Physics and Astronomy ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Time reversal symmetry (TRS) breaking often generates exotic quantum phases in condensed matter. In superconductors, TRS breaking by an external magnetic field not only suppresses superconductivity but also leads to a novel quantum state called the gapless superconducting state. Here we show that magneto-terahertz spectroscopy provides us with a rare opportunity to access and explore the gapless superconducting state of Nb thin films. We present the complete functional form of the superconducting order parameter for an arbitrary magnetic field, for which a fully self-consistent theory is, surprisingly, yet unavailable. We observe a Lifshitz topological phase transition with a vanishing quasiparticle gap everywhere on the Fermi surface, whereas the superconducting order parameter smoothly crosses over from the gapped to the gapless regime. Our observation of the magnetic pair-breaking effects in Nb challenges traditional perturbative theories and opens a pathway to further exploring and manipulating the exotic state of gapless superconductivity.
- Published
- 2023
3. TRPV1 inhibition overcomes cisplatin resistance by blocking autophagy-mediated hyperactivation of EGFR signaling pathway
- Author
-
Se Jin Oh, Ji Yeon Lim, Min Kyu Son, Jun Hyeok Ahn, Kwon-Ho Song, Hyo-Jung Lee, Suyeon Kim, Eun Ho Cho, Joon-Yong Chung, Hanbyoul Cho, Hyosun Kim, Jae-Hoon Kim, Jooyoung Park, Jungmin Choi, Sun Wook Hwang, and Tae Woo Kim
- Subjects
Multidisciplinary ,General Physics and Astronomy ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Cisplatin resistance along with chemotherapy-induced neuropathic pain is an important cause of treatment failure for many cancer types and represents an unmet clinical need. Therefore, future studies should provide evidence regarding the mechanisms of potential targets that can overcome the resistance as well as alleviate pain. Here, we show that the emergence of cisplatin resistance is highly associated with EGFR hyperactivation, and that EGFR hyperactivation is arisen by a transcriptional increase in the pain-generating channel, TRPV1, via NANOG. Furthermore, TRPV1 promotes autophagy-mediated EGF secretion via Ca2+ influx, which activates the EGFR-AKT signaling and, consequentially, the acquisition of cisplatin resistance. Importantly, TRPV1 inhibition renders tumors susceptible to cisplatin. Thus, our findings indicate a link among cisplatin resistance, EGFR hyperactivation, and TRPV1-mediated autophagic secretion, and implicate that TRPV1 could be a crucial drug target that could not only overcome cisplatin resistance but also alleviate pain in NANOG+ cisplatin-resistant cancer.
- Published
- 2023
4. Soluble TGFBI aggravates the malignancy of cholangiocarcinoma through activation of the ITGB1 dependent PPARγ signalling pathway
- Author
-
Jungwhoi Lee, Jungsul Lee, Woogwang Sim, and Jae-Hoon Kim
- Subjects
Extracellular Matrix Proteins ,Cancer Research ,Integrin beta1 ,General Medicine ,Cholangiocarcinoma ,PPAR gamma ,Bile Ducts, Intrahepatic ,Bile Duct Neoplasms ,Oncology ,Transforming Growth Factor beta ,Biomarkers, Tumor ,Humans ,Molecular Medicine ,RNA, Messenger - Abstract
Cholangiocarcinoma is a devastating cancer with a poor prognosis. Previous reports have presented conflicting results on the role of transforming growth factor-β-induced protein (TGFBI) in malignant cancers. Currently, our understanding of the role of TGFBI in cholangiocarcinoma is ambiguous. The aim of the present study was to investigate the role of TGFBI in human cholangiocarcinoma.Iterative patient partitioning (IPP) scoring and consecutive elimination methods were used to select prognostic biomarkers. mRNA and protein expression levels were determined using Gene Expression Omnibus (GEO), Western blot and ELISA analyses. Biological activities of selected biomarkers were examined using both in vitro and in vivo assays. Prognostic values were assessed using Kaplan-Meier and Liptak's z score analyses.TGFBI was selected as a candidate cholangiocarcinoma biomarker. GEO database analysis revealed significantly higher TGFBI mRNA expression levels in cholangiocarcinoma tissues compared to matched normal tissues. TGFBI protein was specifically detected in a soluble form in vitro and in vivo. TGFBI silencing evoked significant anti-cancer effects in vitro. Soluble TGFBI treatment aggravated the malignancy of cholangiocarcinoma cells both in vitro and in vivo through activation of the integrin beta-1 (ITGB1) dependent PPARγ signalling pathway. High TGFBI expression was associated with a poor prognosis in patients with cholangiocarcinoma.Our data suggest that TGFBI may serve as a promising prognostic biomarker and therapeutic target for cholangiocarcinoma.
- Published
- 2022
5. Design optimization of smartphone camera housing fabricated by laser powder bed fusion using thermal analysis
- Author
-
Kyung-Tae Yang, Min-Kyeom Kim, Taehwan Kim, Jae-Hoon Kim, and Jonghwan Suhr
- Subjects
Mechanics of Materials ,Mechanical Engineering - Published
- 2022
6. Regulated in Development and DNA Damage Response 1 Protects Hepatocytes Against Palmitate-induced Lipotoxicity
- Author
-
Jae Hoon Kim, Kyu Min Kim, Ji Hye Yang, Sam Seok Cho, Ji Hyun Lee, and Sung Hwan Ki
- Subjects
Biomedical Engineering ,Bioengineering ,Applied Microbiology and Biotechnology ,Biotechnology - Published
- 2022
7. Effects of Cudrania tricuspidata and Sargassum fusiforme extracts on hair growth in C57BL/6 mice
- Author
-
Priyanka Rajan, Premkumar Natraj, Nak Hyoung Kim, Jae-Hoon Kim, Hyuk Joon Choi, and Chang-Hoon Han
- Subjects
General Medicine - Abstract
Background Cudrania tricuspidata is a perennial plant, and Sargassum fusiforme is a brown seaweed with numerous potential benefits, including anticancer, anti-inflammatory, and antioxidant activities. However, the efficacies of C. tricuspidata and S. fusiforme on hair growth have not yet been elucidated. Therefore, the present study examined the effects of C. tricuspidata and S. fusiforme extracts on hair growth in C57BL/6 mice. Results ImageJ demonstrated that drinking and skin application of C. tricuspidata and/or S. fusiforme extracts significantly increased the hair growth rate in the dorsal skin of C57BL/6 mice compared to the control group. Histological analysis confirmed that drinking and skin application of C. tricuspidata and/or S. fusiforme extracts for 21 days significantly increased the length of hair follicles on the dorsal skin of treated C57BL/6 mice compared to that in the control mice. RNA sequencing analysis revealed that hair growth cycle-related factors (anagen factors) such as Catenin Beta 1 (Ctnnb1) and platelet-derived growth factor (Pdgf) were upregulated (> twofold) only by C. tricuspidate extracts, whereas vascular endothelial growth factor (Vegf) and Wnts were upregulated by both C. tricuspidata or S. fusiforme applications in treated mice (compared to the control mice). In addition, oncostatin M (Osm, a catagen-telogen factor) was downregulated (C. tricuspidata when administered via both skin and drinking mode in treated mice compared to that in control mice. Conclusions Our results suggest that C. tricuspidata and/or S. fusiforme extracts show potential hair growth efficacy by upregulating anagen factor genes, including β-catenin, Pdgf, Vegf, and Wnts, and downregulating catagen-telogen factor genes, including Osm, in C57BL/6 mice. The findings suggest that C. tricuspidata and/or S. fusiforme extracts are potential drug candidates to treat alopecia.
- Published
- 2023
8. Extract of Styrax japonica attenuates glutamate-induced apoptosis via regulating MAPK signaling pathway in HT22 hippocampal cells
- Author
-
Da Hye Jeong, Song-I Han, and Jae-Hoon Kim
- Subjects
Plant Science ,Biotechnology - Abstract
Two-thirds of people with dementia suffer from Alzheimer’s disease, and there is a need to develop treatments with fewer side effects. Cholinergic and glutamate-induced brain damage occurs in the early stages of Alzheimer’s disease, so substances that suppress these symptoms may be potential candidates for the treatment. Ethanol extracts of 40 kinds of oriental medicine plants were examined whether they have acetylcholine esterase (Ache) inhibitory properties. We next investigated whether the ethanol extracts of six oriental medicine plants showing Ache inhibitory activity could inhibit glutamate-induced HT22 cell death. The ethanol extract of Styrax japonica (EESJ) was found to be relatively superior in both inhibitory activities. MTT and annexin V/PI staining assays confirmed that EESJ inhibited glutamate-induced apoptosis in the HT22 mouse hippocampal cells. EESJ also suppressed glutamate-mediated ROS production and attenuated the phosphorylation levels of MAPK members including ERK, JNK, and p38 kinases. Therefore, EESJ is a suitable candidate for developing a substance of Alzheimer’s disease treatment.
- Published
- 2023
9. Colossal angular magnetoresistance in ferrimagnetic nodal-line semiconductors
- Author
-
Bohm-Jung Yang, Jae Hoon Kim, Junho Seo, Ji Eun Lee, Bongjae Kim, Jun Sung Kim, Joonbum Park, Sang-Wook Cheong, Hyunsoo Ha, Eun Sang Choi, Gil Young Cho, Chandan De, S. Park, Yurii Skourski, Kyoo Kim, and Han Woong Yeom
- Subjects
Physics ,Condensed Matter::Materials Science ,Magnetization ,Multidisciplinary ,Condensed matter physics ,Spintronics ,Magnetoresistance ,Ferrimagnetism ,Magnet ,Condensed Matter::Strongly Correlated Electrons ,Magnetic semiconductor ,Degeneracy (mathematics) ,Spin (physics) - Abstract
Efficient magnetic control of electronic conduction is at the heart of spintronic functionality for memory and logic applications1,2. Magnets with topological band crossings serve as a good material platform for such control, because their topological band degeneracy can be readily tuned by spin configurations, dramatically modulating electronic conduction3–10. Here we propose that the topological nodal-line degeneracy of spin-polarized bands in magnetic semiconductors induces an extremely large angular response of magnetotransport. Taking a layered ferrimagnet, Mn3Si2Te6, and its derived compounds as a model system, we show that the topological band degeneracy, driven by chiral molecular orbital states, is lifted depending on spin orientation, which leads to a metal–insulator transition in the same ferrimagnetic phase. The resulting variation of angular magnetoresistance with rotating magnetization exceeds a trillion per cent per radian, which we call colossal angular magnetoresistance. Our findings demonstrate that magnetic nodal-line semiconductors are a promising platform for realizing extremely sensitive spin- and orbital-dependent functionalities. A study reports a colossal angular magnetoresistance in the topological magnet Mn3Si2Te6, resulting from a metal-to-insulator transition caused by controlled lifting of a topological band degeneracy, and discusses the key parameters involved.
- Published
- 2021
10. Functional data analysis for assessing the fatigue life of construction equipment attachments
- Author
-
Sung Hyun Kim, Jong-Won Park, and Jae Hoon Kim
- Subjects
Computer science ,business.industry ,Mechanical Engineering ,Bracket ,Functional data analysis ,Rigidity (psychology) ,Structural engineering ,law.invention ,Integrity management ,Vibration ,Mechanics of Materials ,law ,Prognostics ,Hammer ,business ,Reliability (statistics) - Abstract
In construction machinery, attachments, such as buckets and breakers, that are mounted on the equipment convert the fluid energy of the construction machine into impact energy, vibration energy, etc., depending on the purpose. To ensure the reliability of such attachments under repeated or excessive stress, the fatigue life of the structure must be evaluated in terms of strength and rigidity. The present study focused on symmetric structures. A functional analysis was performed on the field data obtained from the construction machine with an attached vibration hammer, and the fatigue life of the symmetric bracket was assessed. The results were used to develop an accelerated fatigue-life test algorithm for the prediction and health management. Residual-useful-life prognostics of basic data in the prediction of life and failure of attachments used in construction machinery as well as the integrity management of their symmetric structures.
- Published
- 2021
11. NANOG confers resistance to complement-dependent cytotoxicity in immune-edited tumor cells through up-regulating CD59
- Author
-
Sung Wook Son, Eunho Cho, Hanbyoul Cho, Seon Rang Woo, Hyo-Jung Lee, Se Jin Oh, Suyeon Kim, Jae-Hoon Kim, Eun Joo Chung, Joon-Yong Chung, Min Gyu Kim, Kwon-Ho Song, and Tae Woo Kim
- Subjects
Multidisciplinary ,Neoplasms ,Tumor Microenvironment ,Humans ,Apoptosis ,CD59 Antigens ,Complement System Proteins ,Nanog Homeobox Protein ,Trastuzumab - Abstract
Cancer immunoediting drives the adaptation of tumor cells to host immune surveillance. Previously, we have demonstrated that immunoediting driven by cytotoxic T lymphocytes (CTLs) enriches NANOG+ tumor cells with immune-refractory properties. Here, we found that CTL-mediated immune pressure triggered cross-resistance of tumor cells to the complement system, a part of the innate immune system. In this process, NANOG upregulated the membrane-bound complement regulatory protein (mCRP) CD59 through promoter occupancy, thereby contributing to the resistance of tumor cells against complement-dependent cytotoxicity (CDC). Notably, targeting of NANOG sensitized the immune-refractory tumor cells to trastuzumab-mediated CDC. Collectively, our results revealed a possible mechanism through which selection imposed by T-cell based immunotherapy triggered complement-resistant phenotypes in the tumor microenvironment (TME), by establishing a firm molecular link between NANOG and CD59 in immune-edited tumor cells. We believe these results hold important implications for the clinical application of CDC-mediated therapeutic antibody.
- Published
- 2022
12. Epigenetic modification and a role for the E3 ligase RNF40 in cancer development and metastasis
- Author
-
Jae-Hoon Kim, Kyathegowdanadoddi Srinivasa Balaji, Li Liao, Jiangzhou Peng, Junjiang Fu, and Chunli Wei
- Subjects
0301 basic medicine ,Cancer Research ,Ubiquitin-Protein Ligases ,Review Article ,Computational biology ,Gene Expression Regulation, Enzymologic ,Epigenesis, Genetic ,law.invention ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,law ,Neoplasms ,Genetics ,medicine ,Ring finger ,Histone H2B ,Humans ,Epigenetics ,Neoplasm Metastasis ,Cancer genetics ,Molecular Biology ,Gene ,Oncogene ,biology ,medicine.disease ,Neoplasm Proteins ,Ubiquitin ligase ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,biology.protein ,Suppressor - Abstract
RNF40 (OMIM: 607700) is a really interesting new gene (RING) finger E3 ubiquitin ligase containing multiple coiled-coil domains and a C-terminal RING finger motif, which engage in protein–DNA and protein–protein interactions. RNF40 encodes a polypeptide of 1001 amino acids with a predicted molecular mass of 113,678 Da. RNF40 and its paralog RNF20 form a stable heterodimer complex that can monoubiquitylate histone H2B at lysine 120 as well as other nonhistone proteins. Cancer is a major public health problem and the second leading cause of death. Through its protein ubiquitylation activity, RNF40 acts as a tumor suppressor or oncogene to play major epigenetic roles in cancer development, progression, and metastasis, highlighting the essential function of RNF40 and the importance of studying it. In this review, we summarize current knowledge about RNF40 gene structure and the role of RNF40 in histone H2B monoubiquitylation, DNA damage repair, apoptosis, cancer development, and metastasis. We also underscore challenges in applying this information to cancer prognosis and prevention and highlight the urgent need for additional investigations of RNF40 as a potential target for cancer therapeutics.
- Published
- 2020
13. Using Dermofat Grafting in Revision Rhinoplasty
- Author
-
Hyo Sun Ko, Jae Hoon Kim, and Sung Wan Park
- Subjects
Reoperation ,medicine.medical_specialty ,Esthetics ,Grafting (decision trees) ,medicine.medical_treatment ,030230 surgery ,Surgical Flaps ,Rhinoplasty ,Surgical methods ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Retrospective Studies ,Wound dehiscence ,business.industry ,medicine.disease ,Surgery ,Plastic surgery ,Otorhinolaryngology ,Wedge shape ,business ,Revision rhinoplasty - Abstract
For revision surgeries due to complications associated with alloplastic materials, autologous tissues including dermofat are considered. However, graft absorption, shaping, and donor site morbidity remain crucial challenges. This study aimed to present several surgical techniques of dermofat grafting for rhinoplasty to overcome these challenges. Patients who underwent autologous dermofat grafting from January 2015 to October 2019 were retrospectively studied, and those who underwent primary rhinoplasty were excluded. The mid-sacral dermis (with the thickest dermal layer) was selected as the main donor site. During dermal harvesting, fat was resected into a wedge shape, to minimize flap tension and dead space risk. A molding technique was applied to improve graft shape and height and minimize graft absorption. Patient records were reviewed for assessing preoperative evaluations, surgical methods, and complications. For evaluating aesthetic outcomes, three rhinoplasty surgeons, blinded to the study purpose, compared preoperative and postoperative photographs. Among 331 cases undergoing dermofat grafting for revision rhinoplasty, 25 underwent revisions; of these, five, one, and nine cases experienced over-absorption, over-correction, and deviation, respectively. One and eight cases underwent revision due to a widening scar at the dermofat donor site and wound dehiscence, respectively. Notably, one case had inflamed sinus formation. The advanced dermofat graft technique provided favorable results with selection of appropriate donor site and a dermofat graft with subdermal fat. The application of this molding technique and proper management of donor site ameliorated critical disadvantages, thereby providing a safe and effective alternative for revision rhinoplasty. Rhinoplasty
- Published
- 2020
14. Coherent many-body exciton in van der Waals antiferromagnet NiPS3
- Author
-
Abhishek Nag, Young-Woo Son, Laurent Chapon, Soonmin Kang, Jonghyeon Kim, Hyeonsik Cheong, Sungmin Lee, Beom Hyun Kim, M. Garcia-Fernandez, Ke-Jin Zhou, Taehun Kim, Kyung Ik Sim, Seokhwan Yun, Jae Hoon Kim, Jae-Ung Lee, Jiemin Li, Kisoo Park, Kangwon Kim, Je-Geun Park, and A. C. Walters
- Subjects
Condensed Matter::Quantum Gases ,Physics ,Multidisciplinary ,Photoluminescence ,Condensed matter physics ,Condensed Matter::Other ,Exciton ,02 engineering and technology ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,021001 nanoscience & nanotechnology ,01 natural sciences ,symbols.namesake ,0103 physical sciences ,Bound state ,Quasiparticle ,symbols ,Coherent states ,Condensed Matter::Strongly Correlated Electrons ,Singlet state ,van der Waals force ,010306 general physics ,0210 nano-technology ,Néel temperature - Abstract
An exciton is the bosonic quasiparticle of electron–hole pairs bound by the Coulomb interaction1. Bose–Einstein condensation of this exciton state has long been the subject of speculation in various model systems2,3, and examples have been found more recently in optical lattices and two-dimensional materials4–9. Unlike these conventional excitons formed from extended Bloch states4–9, excitonic bound states from intrinsically many-body localized states are rare. Here we show that a spin–orbit-entangled exciton state appears below the Neel temperature of 150 kelvin in NiPS3, an antiferromagnetic van der Waals material. It arises intrinsically from the archetypal many-body states of the Zhang–Rice singlet10,11, and reaches a coherent state assisted by the antiferromagnetic order. Using configuration-interaction theory, we determine the origin of the coherent excitonic excitation to be a transition from a Zhang–Rice triplet to a Zhang–Rice singlet. We combine three spectroscopic tools—resonant inelastic X-ray scattering, photoluminescence and optical absorption—to characterize the exciton and to demonstrate an extremely narrow excitonic linewidth below 50 kelvin. The discovery of the spin–orbit-entangled exciton in antiferromagnetic NiPS3 introduces van der Waals magnets as a platform to study coherent many-body excitons. A spin–orbit-entangled exciton state in the van der Waals material NiPS3 is observed, and found to arise from many-body states of a Zhang–Rice singlet.
- Published
- 2020
15. Association of Jagged1 expression with malignancy and prognosis in human pancreatic cancer
- Author
-
Jungwhoi Lee, Jae-Hoon Kim, and Jungsul Lee
- Subjects
0301 basic medicine ,Cancer Research ,JAG1 ,Notch signaling pathway ,Mice, Nude ,Antineoplastic Agents ,Deoxycytidine ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,Cell Line, Tumor ,Pancreatic cancer ,Animals ,Humans ,Medicine ,Gene silencing ,Gene Silencing ,RNA, Messenger ,Notch 1 ,Mice, Inbred BALB C ,business.industry ,Kinase ,General Medicine ,Prognosis ,medicine.disease ,Gemcitabine ,Gene Expression Regulation, Neoplastic ,Pancreatic Neoplasms ,030104 developmental biology ,Oncology ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,Cancer research ,Molecular Medicine ,business ,Jagged-1 Protein ,Signal Transduction ,medicine.drug - Abstract
Pancreatic cancer is one of the most aggressive cancers. Preclinical and clinical data indicate that Notch 1 ligand jagged1 (JAG1) plays a pro-oncogenic role in several malignant cancers. As yet, however, the role of JAG1 in pancreatic cancer is poorly understood. The objective of the present study was to investigate JAG1 as a therapeutic target in human pancreatic cancer. Expression levels of Notch signaling molecules were assessed using GEO datasets and Western blot analysis, respectively. Anti-tumor effects following JAG1 silencing were evaluated using in vitro and in vivo assays. Prognostic implications were assessed using GEO datasets. Using GEO datasets and Western blot analysis we detected significantly higher JAG1 mRNA and protein expression levels in pancreatic cancer compared to normal pancreatic tissues. JAG1 silencing significantly restrained the growth, migration and invasion of pancreatic cancer cells through the induction of apoptosis and blockade of various kinases independent of the Notch1 pathway. Combined JAG1 silencing and gemcitabine treatment showed synergistic anti-viability effects in human pancreatic cancer cells. JAG1 silencing also resulted in significant anti-cancer effects in vivo and high JAG1 expression was found to be associated with an adverse prognosis in pancreatic cancer patients. From our data we conclude that JAG1 may be a promising therapeutic target in pancreatic cancer.
- Published
- 2020
16. Hepatocyte CREBH deficiency aggravates inflammatory liver injury following chemokine-dependent neutrophil infiltration through upregulation of NF-κB p65 in mice
- Author
-
Soon-Young Na, Jung-Ran Noh, Yong-Hoon Kim, Chul-Ho Lee, Lee In-Bok, Hueng-Sik Choi, Tae Geol Lee, Young-Won Seo, Choi Jung Hyeon, Yun Jeong Seo, and Jae-Hoon Kim
- Subjects
Male ,0301 basic medicine ,Chemokine ,Health, Toxicology and Mutagenesis ,Inflammation ,010501 environmental sciences ,Toxicology ,01 natural sciences ,03 medical and health sciences ,Transactivation ,chemistry.chemical_compound ,Downregulation and upregulation ,Concanavalin A ,medicine ,Animals ,Humans ,Cyclic AMP Response Element-Binding Protein ,0105 earth and related environmental sciences ,Mice, Knockout ,Liver injury ,biology ,Transcription Factor RelA ,NF-κB ,General Medicine ,medicine.disease ,Up-Regulation ,Mice, Inbred C57BL ,HEK293 Cells ,030104 developmental biology ,medicine.anatomical_structure ,Neutrophil Infiltration ,chemistry ,Hepatocyte ,biology.protein ,Cancer research ,Cytokines ,Chemical and Drug Induced Liver Injury ,Chemokines ,medicine.symptom ,Massive Hepatic Necrosis - Abstract
Fulminant hepatitis is a serious inflammatory condition of the liver characterized by massive necrosis of liver parenchyma following excessive immune cell infiltration into the liver, and possibly causing sudden hepatic failure and medical emergency. However, the underlying mechanisms are not fully understood. Here, we investigated the role of cyclic AMP-responsive element-binding protein, hepatocyte specific (CREBH) in concanavalin A (ConA)-driven hepatitis-evoked liver injury. C57BL/6J (WT) and Crebh knockout (KO) mice injected with ConA (7.5 or 25 mg/kg) and bone marrow (BM) chimeric mice, generated by injection of BM cells into sub-lethally irradiated recipients followed by ConA injection (22.5 or 27.5 mg/kg) 8 weeks later, were used for in vivo study. Primary mouse hepatocytes and HEK293T cells were used for a comparative in vitro study. Crebh KO mice are highly susceptible to ConA-induced liver injury and prone to death due to increased neutrophil infiltration driven by enhanced hepatic expression of neutrophil-attracting chemokines. Notably, BM chimera experiment demonstrated that Crebh-deficient hepatocytes have an enhanced ability of recruiting neutrophils to the liver, thereby promoting hepatotoxicity by ConA. Intriguingly, in vitro assays showed that p65, a subunit of NF-κB and common transcription factor for various chemokines, dependent transactivation was inhibited by CREBH. Furthermore, p65 expression was inversely correlated with CREBH level in ConA-treated mice liver and TNFα-stimulated primary mouse hepatocytes. This is the first demonstration that CREBH deficiency aggravates inflammatory liver injury following chemokine-dependent neutrophil infiltration via NF-κB p65 upregulation. CREBH is suggested to be a novel therapeutic target for treatment of fulminant hepatitis.
- Published
- 2019
17. Hold Time-Low Cycle Fatigue Behavior of Nickel Based Hastelloy X at Elevated Temperatures
- Author
-
Dong Hyun Yoon, Sungho Chang, Jae-Hoon Kim, Sungyong Chang, and Inkang Heo
- Subjects
0209 industrial biotechnology ,Materials science ,Hold time ,Scanning electron microscope ,Mechanical Engineering ,Nuclear engineering ,Fractography ,02 engineering and technology ,Nickel based ,Industrial and Manufacturing Engineering ,Total strain ,020303 mechanical engineering & transports ,020901 industrial engineering & automation ,0203 mechanical engineering ,Creep ,Waveform ,Low-cycle fatigue ,Electrical and Electronic Engineering - Abstract
Hastelloy X, a material used in gas turbines, is subject to complex damage because of creep and fatigue in a high temperature environment during the operation of gas turbines. Although the low cycle behavior of Hastelloy X has been widely investigated, the number of studies focusing on the actual operating conditions of the gas turbine is limited. In this study, the total strain range of the gas turbine at 760 °C and 870 °C was considered as a parameter of the actual gas turbine operation. In addition, tests were performed with a trapezoidal waveform of the total strain to reflect the operation—stop status of the gas turbine with frequent shutdown times. The results of the fatigue test were studied with the Coffin-Manson method and the lifetime prediction equation was derived based on the data. Fractography was performed using scanning electron microscopy (SEM) observation.
- Published
- 2019
18. Visualization for internet of things: power system and financial network cases
- Author
-
Jae-Hoon Kim, Myungjong Kim, Wooyeon Jo, and Taeshik Shon
- Subjects
Finance ,Network forensics ,Interconnection ,Service (systems architecture) ,Computer Networks and Communications ,Computer science ,business.industry ,Network packet ,020207 software engineering ,Cloud computing ,02 engineering and technology ,Industrial control system ,Critical infrastructure ,DNP3 ,Hardware and Architecture ,0202 electrical engineering, electronic engineering, information engineering ,Media Technology ,business ,Software ,Information exchange - Abstract
National critical infrastructure networks, such as banks and industrial control systems (ICSs), can be serious damaged in the event of a security incident. Therefore, in all these major infrastructures, closed networks are constructed to cut off the attack path. However, owing to the emergence of cloud, Internet of Things (IoT), and artificial intelligence (AI) services, network interconnection is rapidly increasing; thus, many major infrastructure networks can no longer be called closed networks. The ICS, which was previously a strictly closed network, is now usually called Industrial Internet of Things (IIoT) and exhibits many changes, such as smart factories and remote control. Many payment modules use the financial network through IoT or AI-assisted services. In this massive connected environment, the existing closed network defense system may cause difficulties in providing the service. Therefore, there is a need for technology that can continuously monitor the possibility of advanced attacks. In this paper, we define the normal-behavior-based rules from the perspective of network forensics and conduct visualization studies to detect all possible attacks against the control protocol DNP3 (Distributed Network Protocol) and the financial protocol called FIX (Finance Information Exchange). Thus, we detected suspicious network packets on the ICS network and the financial network and identified abnormal behavior that could be the basis of serious attacks.
- Published
- 2018
19. Simultaneous emission of orthogonal handedness in circular polarization from a single luminophore
- Author
-
Kyungmin Baek, Jeong-Dae Seo, Jae-Hoon Kim, Dong-Myung Lee, Yu-Jin Lee, Hyun-Chul Choi, In-Byeong Kang, and Chang-Jae Yu
- Subjects
lcsh:Applied optics. Photonics ,Materials science ,Polymers ,02 engineering and technology ,Electroluminescence ,010402 general chemistry ,01 natural sciences ,Article ,chemistry.chemical_compound ,lcsh:QC350-467 ,Circular polarization ,Diode ,Birefringence ,Dopant ,Photonic devices ,business.industry ,lcsh:TA1501-1820 ,Dichroism ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry ,Luminophore ,Optoelectronics ,0210 nano-technology ,business ,Luminescence ,lcsh:Optics. Light - Abstract
The direct emission of circularly polarized (CP) light improves the efficiency of an organic light-emitting diode and characterizes the secondary structure of proteins. In most cases, CP light is generated from a luminescent layer containing chiral characteristics, thereby generating only one kind of CP light in an entire device. Here, we propose direct CP light emissions using a twisted achiral conjugate polymer without any chiral dopant as an emitting layer (EML). The twisted structure is induced in the mesogenic conjugate polymer due to its elasticity by applying different alignment directions to its upper and lower interfaces. Furthermore, we demonstrate the simultaneous emission of orthogonal CP light in a single luminescent device by patterning different alignment directions on the surfaces of the EML. The light source with multipolarization including the orthogonal CP states is applicable to many applications in biosensors and optical devices., Simultaneous right and left circular polarization from single device Both right- and left-handed circularly polarized light were generated from a single device, paving the way for novel applications in biosensors and organic LEDs. Chang-Jae Yu of Hanyang University in Korea and colleagues fabricated the device by using the liquid crystal phase of a polymer, called F8BT, which is commonly used in organic light-emitting diodes. They controlled the alignment of the molecules inside the polymer by rubbing its upper and lower surfaces in specific directions. The rubbing caused the molecules inside the polymer to align and twist. Light passing through the polymer simultaneously emerges as right- and left-handed circularly moving electromagnetic waves. The study demonstrates the feasibility of a light source with multiple polarizations, which could have applications in a variety of optical devices.
- Published
- 2019
20. Influence of the Carrier Pinhole Position Errors on the Load Sharing of a Planetary Gear Train
- Author
-
Joo-Young Oh, Geun-Ho Lee, Young-Jun Park, Jae-Hoon Kim, Sang-Dae Lee, and Jeong-Gil Kim
- Subjects
0209 industrial biotechnology ,Bearing (mechanical) ,Computer science ,Mechanical Engineering ,Load sharing ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,02 engineering and technology ,GeneralLiterature_MISCELLANEOUS ,Industrial and Manufacturing Engineering ,Automotive engineering ,law.invention ,Laboratory test ,Gear train ,020303 mechanical engineering & transports ,020901 industrial engineering & automation ,0203 mechanical engineering ,law ,Position (vector) ,Service life ,Pinhole (optics) ,Electrical and Electronic Engineering ,Floating system - Abstract
Load sharing among planetary gears, one of the design variables, has a significant influence on the performance and service life of a gearbox. This study involved simulating and testing the design parameters related to load sharing among planetary gears. In this regard, the influence of errors in the carrier pinhole position on the load sharing among the planetary gears was analyzed. The results showed that the difference between the simulation results using the model and the laboratory test results was less than 10%. Furthermore, similar tendencies were observed according to the magnitude of the load applied to the planetary gears. As for the design parameters affecting load sharing, the service life of a gearbox containing planetary gears can be extended by using a floating system as opposed to a non-floating system. In addition, reduced planetary pin diameter and increased planetary bearing clearance leads to appropriate load sharing among the planetary gears and increases the service life and floating effect of the gearbox.
- Published
- 2018
21. An adaptive importance sampling method with a Kriging metamodel to calculate failure probability
- Author
-
Seunggyu Lee and Jae-Hoon Kim
- Subjects
Statistical distance ,Basis (linear algebra) ,Markov chain ,Mechanical Engineering ,Kernel density estimation ,020101 civil engineering ,02 engineering and technology ,0201 civil engineering ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Mechanics of Materials ,Kernel (statistics) ,Applied mathematics ,Limit state design ,Completeness (statistics) ,Importance sampling ,Mathematics - Abstract
A Markov chain simulation was performed to extract points in a failure region. A Kriging metamodel was constructed to approximate a limit state based on the points extracted by the Markov chain simulation. A kernel sampling density was constructed to approximate the optimal importance sampling density. The points extracted in the failure region by the Markov chain simulation were assumed as a mean of each kernel. An importance sampling method was applied to calculate the failure probability. In the importance sampling method, points are extracted from the kernel in the vicinity of a limit state. Considering the statistical distance as well as the learning function, additional experimental points were selected for the kriging metamodel. A stable numerical calculation method was applied to find the parameters of the kernel sampling density. The completeness of the Kriging metamodel was evaluated on the basis of possible changes in failure probability.
- Published
- 2017
22. Fatigue analysis of spot-welded automobile components considering fatigue damage-induced stiffness degradation in time and frequency domains
- Author
-
Young-Sam Ham, Dong-Chul Lee, Jae-Hoon Kim, Ki-Weon Kang, and Jang-Ho Lee
- Subjects
Materials science ,Fatigue damage ,02 engineering and technology ,Welding ,Industrial and Manufacturing Engineering ,law.invention ,0203 mechanical engineering ,law ,medicine ,Electrical and Electronic Engineering ,Composite material ,business.industry ,Mechanical Engineering ,Outrigger ,technology, industry, and agriculture ,Stiffness ,Structural engineering ,respiratory system ,021001 nanoscience & nanotechnology ,Finite element method ,020303 mechanical engineering & transports ,Stiffness degradation ,Frequency domain ,medicine.symptom ,0210 nano-technology ,business ,Vibration fatigue - Abstract
In this study, fatigue analysis was performed on a multi-point spot-welded outrigger structure utilized in an automobile engine room, where stiffness degradation from accumulated fatigue damage were considered. The S-N curve was obtained through a fatigue test on a single-point tensile-shear spot-welded specimen under constant amplitude load and finite element analysis based on the Rupp/LBF model. Fatigue analyses were performed in the time and frequency domains on the spot-welded outrigger structure, where changes in the local stress distribution and transfer function due to accumulated fatigue damage to the welding points were considered. Based on these results, it can be stated that the fatigue life of multi-point spot-welded structure under random loading should be evaluated considering the stiffness changes due to accumulated fatigue damage under the frequency domain.
- Published
- 2017
23. Influence of a clutch control current profile to improve shift quality for a wheel loader automatic transmission
- Author
-
Joo-Young Oh, Jeong-Gil Kim, Jin-Young Park, Jae-Hoon Kim, Jung-Woo Cho, and Geun-Ho Lee
- Subjects
0209 industrial biotechnology ,Engineering ,Automatic transmission ,Powertrain ,Pressure control ,business.industry ,Mechanical Engineering ,02 engineering and technology ,Clutch control ,Industrial and Manufacturing Engineering ,law.invention ,Loader ,Jerk ,Piston ,020303 mechanical engineering & transports ,020901 industrial engineering & automation ,0203 mechanical engineering ,law ,Clutch ,Electrical and Electronic Engineering ,business ,Simulation - Abstract
A loader is a construction machine to upload soil into trucks or to transport those materials. As a kind of loaders, a wheel-loader, which is driven by wheels, has been widely used. Since a wheel-loader with an automatic transmission operates in the adverse environments such as constructions sites, the shift quality has not been addressed as a main research topic. However, the necessary for researches to improve the shift quality of automatic transmission raised to develop control technology for operator’s convenience. In this study, a wheel-loader’s power train with an automatic transmission was analytically modeled and then the shift quality was analyzed based on power train modeling. An analytical model of wheel-loader’s power train is verified by comparing experimental and simulated results under the same operational conditions. Since the shift performance is affected by the pressure in clutch piston, current profile of a proportional pressure control valve to control the automatic transmission was varied for the simulation verification. In the simulations, it was analyzed in terms of shift performance in each stage of fast filling, take-over and clutch slippage, and clutch slippage time. Finally, relative amplitude of jerk is used in order to decide the regular shift performance.
- Published
- 2017
24. Molecular cloning and characterization of a flavonoid glucosyltransferase from Byungkyool (Citrus platymamma hort. ex Tanaka)
- Author
-
Myeung Seung Kim, Jae-Hoon Kim, Song-I Han, Sung Jin Chung, and Jungwhoi Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,chemistry.chemical_classification ,Naringenin ,biology ,Organic Chemistry ,Flavonoid ,food and beverages ,Eriodictyol ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Flavonols ,Biochemistry ,chemistry ,biology.protein ,heterocyclic compounds ,Glucosyltransferase ,Quercetin ,Kaempferol ,Luteolin ,010606 plant biology & botany - Abstract
Uridine diphosphate glucosyltransferase (UGT) attaches glucoside to proteins, various flavonoids, and phenolic compounds. The modification of flavonoid affects its water solubility, stability, and bioavailability of flavonoids. In this study, citrus genomic sequence database was searched for UGTs of citrus, and a UDP-glucosyltransferase (bGT173) was isolated from Byungkyool (Citrus platymamma hort. ex Tanaka). The cloned cDNA gene was 1365 bp in length and encoded 456 amino acids. Phylogenetic analysis suggested that bGT173 was a member of the flavonoid 3-O-glucosyltransferase group. mRNA expression of bGT173 was higher in leaves compared to flowers, stems, and fruits. The recombinant protein of bGT173 was expressed in Escherichia coli, and tested for its activity on seven flavonoids (apigenin, eriodictyol, hesperetin, kaempferol, luteolin, naringenin, and quercetin). Both kaempferol and quercetin were good substrates for bGT173, demonstrating that bGT173 preferentially glucosylated the 3-hydroxyl group of flavonols. Furthermore, quercetin 3-O-glucoside produced in E. coli showed the same anti-migration activity on pancreatic cancer cells similar to the standard chemical, suggesting that bGT173 is a good candidate for bioconversion of quercetin to quercetin 3-O-glucoside.
- Published
- 2017
25. Directed self-assembly of a helical nanofilament liquid crystal phase for use as structural color reflectors
- Author
-
Ewa Gorecka, Dong Ki Yoon, Taewoo Ha, Wongi Park, Teun-Teun Kim, Damian Pociecha, Taek Sun Jung, Hyungju Ahn, Jae Hoon Kim, Tae Joo Shin, Anna Zep, and Kyung Ik Sim
- Subjects
Molecular switch ,Fabrication ,Nanostructure ,Materials science ,business.industry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Azobenzene ,chemistry ,Liquid crystal ,law ,Modeling and Simulation ,Optoelectronics ,General Materials Science ,Photolithography ,0210 nano-technology ,business ,Structural coloration ,Visible spectrum - Abstract
The fabrication of molecular structures with a desired morphology, e.g., nanotubes, nanoribbons, nanosprings, and sponges, is essential for the advancement of nanotechnology. Unfortunately, realization of this objective is expensive and complicated. Here, we report that irradiating a film comprising azobenzene derivatives with UV light produces oriented arrays of helical nanofilaments via the photoisomerization-induced Weigert effect. As a result, structural colors are observed due to the extrinsic chiral reflection in the visible wavelength range, and the reflected color can be tuned by adjusting the molecular length of the azobenzene derivative. This simple fabrication method can be used for fabricating large, reversible, and patternable color reflectors, providing a new platform for interference-based structural coloration as it exists in nature, such as morpho butterflies, green-winged teal, and various beetles. A thin film that produces colors more vibrant and durable than typical pigments has been created with the help of a light-sensitive molecular switch. The rich hues seen in butterfly wings do not arise from light-absorbing pigments. Instead, they are due to complex nanostructures reflecting light, generating fade-free ‘structural’ colors. Dong Ki Yoon from KAIST in Daejeon, South Korea, and co-workers now report that helical nanofilament liquid crystals containing azobenzene, a molecule that changes shape when exposed to strong light, can self-assemble into structural color reflectors. The team used ultraviolet radiation to orient the helical structures into ordered arrays of nanofilaments on a solid surface. Structural colors emitted by these nanofilament films could be tuned by adjusting the length of the azobenzene unit or erased by applying heat. We demonstrate an aligned array of helical nanostructures via the Weigert effect, which can be used in patternable and reversible structural color reflectors. To the best of our knowledge, this is the first demonstration of a photolithography technique applied to a perfectly orientationally ordered medium, here liquid crystal material, itself; the mechanism is connected to the chiral optics.
- Published
- 2019
26. Blockade of integrin α3 attenuates human pancreatic cancer via inhibition of EGFR signalling
- Author
-
Jungsul Lee, Jae Hoon Kim, Chulhee Choi, and Jungwhoi Lee
- Subjects
0301 basic medicine ,Cell Survival ,Integrin alpha3 ,Integrin ,lcsh:Medicine ,Mice, Nude ,Kaplan-Meier Estimate ,Article ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Western blot ,Cell Movement ,Cell Line, Tumor ,Pancreatic cancer ,Databases, Genetic ,Animals ,Humans ,Gene silencing ,Medicine ,Epidermal growth factor receptor ,RNA, Small Interfering ,lcsh:Science ,Receptor ,Membrane Glycoproteins ,Multidisciplinary ,medicine.diagnostic_test ,biology ,business.industry ,lcsh:R ,Transfection ,Prognosis ,medicine.disease ,Up-Regulation ,Blockade ,ErbB Receptors ,Pancreatic Neoplasms ,030104 developmental biology ,Cancer research ,biology.protein ,lcsh:Q ,RNA Interference ,business ,030217 neurology & neurosurgery ,Signal Transduction - Abstract
The prognosis of pancreatic cancer remains dismal despite continuous and considerable efforts. Integrins (ITGs) are highly expressed in various malignant cancers. However, very few studies investigated the role of integrin α3 (ITGα3) in malignant cancers. Here, we determined the functional role of ITGα3 in pancreatic cancer. Analysis of public microarray databases and Western blot analysis indicated a unique expression of ITGα3 in human pancreatic cancer. Silencing ITGα3 expression significantly inhibited the viability and migration of human pancreatic cancer cells. Notably, ablation of ITGα3 expression resulted in a significant decrease of epidermal growth factor receptor (EGFR) expression compared with transfection of control-siRNA through an increased number of leucine-rich repeats and immunoglobulin-like domain protein 1 (LRIG1) expression. In addition, ablating ITGα3 inhibited tumour growth via blockade of EGFR signalling in vivo. Furthermore, the highly expressed ITGα3 led to a poor prognosis of pancreatic cancer patients. Our results provide novel insights into ITGα3-induced aggressive pancreatic cancer.
- Published
- 2019
27. Inhibitory effects of bee venom and its components against viruses in vitro and in vivo
- Author
-
Tae-Hwan Kim, Byeong-Hoon Lee, Chamilani Nikapitiya, Jong-Soo Lee, Jae-Hoon Kim, Chul-Joong Kim, Hyun-Cheol Lee, Choul Goo Kim, and Bashir Uddin
- Subjects
0301 basic medicine ,Simplexvirus ,food.ingredient ,viruses ,anti-viral activity ,Biology ,Virus Replication ,medicine.disease_cause ,Antiviral Agents ,Applied Microbiology and Biotechnology ,Microbiology ,Virus ,Cell Line ,Mice ,03 medical and health sciences ,Influenza A Virus, H1N1 Subtype ,food ,Orthomyxoviridae Infections ,Viral envelope ,Virology ,Influenza A virus ,medicine ,Animals ,Enterovirus ,030102 biochemistry & molecular biology ,virucidal effect ,General Medicine ,biology.organism_classification ,Melitten ,bee venom ,Bee Venoms ,030104 developmental biology ,Herpes simplex virus ,Apamin ,melittin ,Viral replication ,Vesicular stomatitis virus ,Viruses ,Erratum - Abstract
Bee venom (BV) from honey bee (Apis Melifera L.) contains at least 18 pharmacologically active components including melittin (MLT), phospholipase A2 (PLA2), and apamin etc. BV is safe for human treatments dose dependently and proven to possess different healing properties including antibacterial and antiparasitidal properties. Nevertheless, antiviral properties of BV have not well investigated. Hence, we identified the potential antiviral properties of BV and its component against a broad panel of viruses. Co-incubation of non-cytotoxic amounts of BV and MLT, the main component of BV, significantly inhibited the replication of enveloped viruses such as Influenza A virus (PR8), Vesicular Stomatitis Virus (VSV), Respiratory Syncytial Virus (RSV), and Herpes Simplex Virus (HSV). Additionally, BV and MLT also inhibited the replication of non-enveloped viruses such as Enterovirus-71 (EV-71) and Coxsackie Virus (H3). Such antiviral properties were mainly explained by virucidal mechanism. Moreover, MLT protected mice which were challenged with lethal doses of pathogenic influenza A H1N1 viruses. Therefore, these results provides the evidence that BV and MLT could be a potential source as a promising antiviral agent, especially to develop as a broad spectrum antiviral agent.
- Published
- 2016
28. An experimental study on the effect of carrier pinhole position errors on planet gear load sharing
- Author
-
Geun-Ho Lee, Jeong-Gil Kim, Young-Jun Park, and Jae-Hoon Kim
- Subjects
0209 industrial biotechnology ,Engineering ,business.industry ,Tension (physics) ,Mechanical Engineering ,02 engineering and technology ,Structural engineering ,Compression (physics) ,Turbine ,Industrial and Manufacturing Engineering ,020303 mechanical engineering & transports ,020901 industrial engineering & automation ,0203 mechanical engineering ,Planet ,Position (vector) ,Torque ,Pinhole (optics) ,Electrical and Electronic Engineering ,business ,Simulation ,Strain gauge - Abstract
In this study, the test was conducted to verify the effect of carrier pinhole position errors on planetary gearbox load sharing. A 3D measurement was conducted to check the pinhole position errors of a carrier that was produced at an actual industrial site. A strain gauge was attached to the planet pin. The effect of planet pin manufacturing errors and the difference in errors according to the installation position of the strain gauge were examined. The effect of carrier pinhole position errors on planetary gearbox load sharing was examined for different input torques. As the input torque increased, load sharing was improved. When the test torque rate was 100%, the load sharing factor was 1.42 for the strain gauge under compression and 1.34 for the strain gauge under tension. These results were similar to the load sharing factor indicated in the design standards for wind turbine gearbox designs.
- Published
- 2016
29. Infection-specific phosphorylation of glutamyl-prolyl tRNA synthetase induces antiviral immunity
- Author
-
Myung Hee Kim, Jungwon Hwang, Jae U. Jung, Hyun Kwan Kim, Tae-Hwan Kim, Chul-Ho Lee, Jong-Hwan Kim, Jong-Soo Lee, Abul Arif, Seong Jun Park, Eun-Young Lee, Yong-Hoon Kim, Hyun-Cheol Lee, Sunghoon Kim, Seon-Young Kim, Young Ki Choi, Paul L. Fox, Cheolju Lee, Song Yee Jang, and Jae-Hoon Kim
- Subjects
0301 basic medicine ,Knockout ,Immunology ,Regulator ,Biology ,Virus Replication ,Antiviral Agents ,Article ,Amino Acyl-tRNA Synthetases ,Mice ,03 medical and health sciences ,RNA Virus Infections ,Immune system ,Ubiquitin ,Animals ,RNA Viruses ,Innate ,Immunology and Allergy ,Phosphorylation ,Disease Resistance ,Mitochondrial antiviral-signaling protein ,Mice, Knockout ,Animal ,Ubiquitination ,Immunity ,RNA-Binding Proteins ,EPRS ,Virology ,Immunity, Innate ,Cell biology ,Disease Models, Animal ,Infectious Diseases ,Good Health and Well Being ,030104 developmental biology ,Viral replication ,Virus Diseases ,Disease Models ,Host-Pathogen Interactions ,biology.protein ,Signal transduction ,Peptides ,Infection ,Signal Transduction ,Protein Binding - Abstract
The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/−) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.
- Published
- 2016
30. High efficiency n-Si/p-Cu2O core-shell nanowires photodiode prepared by atomic layer deposition of Cu2O on well-ordered Si nanowires array
- Author
-
Soo-Hyun Kim, Kyung Yong Ko, Jihun Oh, Hyungjun Kim, Hangil Kim, Han-Bo-Ram Lee, and Jae-Hoon Kim
- Subjects
010302 applied physics ,Photocurrent ,Materials science ,Silicon ,Nanowire ,Analytical chemistry ,chemistry.chemical_element ,Biasing ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Electronic, Optical and Magnetic Materials ,Photodiode ,law.invention ,Atomic layer deposition ,chemistry ,law ,Etching (microfabrication) ,0103 physical sciences ,Thin film ,0210 nano-technology - Abstract
A highly efficient n-Si/p-Cu2O core-shell (C-S) nanowire (NW) photodiode was fabricated using Cu2O grown by atomic layer deposition (ALD) on a well-ordered Si NW array. Ordered Si nanowires arrays were fabricated by nano-sphere lithography to pattern metal catalysts for the metal-assisted etching of silicon, resulting in a Si NW arrays with a good arrangement, smooth surface and small diameter distribution. The ALD-Cu2O thin films were grown using a new non-fluorinated Cu precursor, bis(1-dimethylamino-2-methyl-2-butoxy)copper (C14H32N2O2Cu), and water vapor (H2O) at 140°C. Transmission electron microscopy equipped with an energy dispersive spectrometer confirmed that p-Cu2O thin films had been coated over arrayed Si NWs with a diameter of 150 nm (aspect ratio of ∼7.6). The C-S NW photodiode exhibited more sensitive photodetection performance under ultraviolet illumination as well as an enhanced photocurrent density in the forward biasing region than the planar structure diode. The superior performance of C-S NWs photodiode was explained by the lower reflectance of light and the effective carrier separation and collection originating from the C-S NWs structure.
- Published
- 2016
31. Clinical significance of fibroblast growth factor receptor 2 expression in patients with residual rectal cancer after preoperative chemoradiotherapy: relationship with KRAS or BRAF mutations and MSI status
- Author
-
Ghilsuk Yoon, Hwa Young Lee, Keun Hur, An Na Seo, and Jae Hoon Kim
- Subjects
Male ,0301 basic medicine ,Oncology ,Neoplasm, Residual ,Colorectal cancer ,medicine.medical_treatment ,DNA Mutational Analysis ,Perineural invasion ,Kaplan-Meier Estimate ,medicine.disease_cause ,Polymerase Chain Reaction ,0302 clinical medicine ,Neoadjuvant therapy ,Aged, 80 and over ,Univariate analysis ,General Medicine ,Middle Aged ,Prognosis ,Immunohistochemistry ,Neoadjuvant Therapy ,030220 oncology & carcinogenesis ,Adenocarcinoma ,Female ,Microsatellite Instability ,KRAS ,Adult ,Proto-Oncogene Proteins B-raf ,musculoskeletal diseases ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Disease-Free Survival ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,Internal medicine ,Biomarkers, Tumor ,medicine ,Humans ,Clinical significance ,Receptor, Fibroblast Growth Factor, Type 2 ,Aged ,Proportional Hazards Models ,Rectal Neoplasms ,business.industry ,Microsatellite instability ,Chemoradiotherapy, Adjuvant ,medicine.disease ,stomatognathic diseases ,030104 developmental biology ,Mutation ,business - Abstract
This study was designed to determine the prognostic impact and clinical significance of FGFR2 in residual disease after preoperative chemoradiotherapy (CRT) in patients with rectal cancer. The surgical specimens of 145 patients with residual rectal cancer after preoperative CRT were analyzed. To evaluate FGFR2 expression, immunohistochemistry was performed on whole section tissues. KRAS exon 2 (codon 12 and 13), BRAF V600E mutational status, and microsatellite instability (MSI) were determined using polymerase chain reactions. Of the eligible 141 patients, FGFR2 over-expression was observed in 75.9 % (n = 107) and was correlated with perineural invasion (P = 0.005) and inferior tumor regression grading (TRG) (P = 0.009). However, FGFR2 expression had no relationship with KRAS and BRAF mutation results or with MSI results. On univariate analysis, FGFR2 over-expression was significantly associated with worse rectal cancer-specific survival (RCSS) (P = 0.005) and disease-free survival (DFS) (P = 0.035). However, multivariate analysis revealed that FGFR2 over-expression was not independently associated with RCSS and DFS (all P > 0.05). Although FGFR2 over-expression did not independently influence patient outcome, FGFR2 over-expression was associated with worse prognosis and inferior TRG. Our data may aid in understanding the therapeutic approaches targeting FGFR2 in patients with residual rectal cancer after preoperative CRT.
- Published
- 2016
32. Quercetin 3-O-glucoside suppresses epidermal growth factor–induced migration by inhibiting EGFR signaling in pancreatic cancer cells
- Author
-
Jae-Hoon Kim, Jungwhoi Lee, Jeong Hun Yun, and Song-I Han
- Subjects
medicine.medical_specialty ,MAP Kinase Signaling System ,Apoptosis ,chemistry.chemical_compound ,Glucosides ,Cell Movement ,Epidermal growth factor ,Cell Line, Tumor ,Internal medicine ,Pancreatic cancer ,medicine ,Humans ,heterocyclic compounds ,Phosphorylation ,Receptor ,Protein kinase B ,Flavonoids ,Epidermal Growth Factor ,Cell migration ,General Medicine ,medicine.disease ,Gemcitabine ,ErbB Receptors ,Pancreatic Neoplasms ,Endocrinology ,chemistry ,Cancer research ,Quercetin ,Signal transduction ,medicine.drug - Abstract
Pancreatic cancer is one of the most dangerous cancers and is associated with a grave prognosis. Despite increased knowledge of the complex signaling networks responsible for progression of pancreatic cancer, many challenging therapies have fallen short of expectations. In this study, we examined the anti-migratory effect of quercetin 3-O-glucoside in epidermal growth factor-induced cell migration by inhibiting EGF receptor (EGFR) signaling in several human pancreatic cancer cell lines. Treatment with quercetin, quercetin 3-O-glucoside, and quercetin 7-O-glucoside differentially suppressed epidermal growth factor-induced migration activity of human pancreatic cancer cells. In particular, quercetin 3-O-glucoside strongly inhibited the infiltration activity of pancreatic cancer cells in a dose-dependent manner. Furthermore, quercetin 3-O-glucoside exerted the anti-migratory effect even at a relatively low dose compared with other forms of quercetin. The anti-tumor effects of quercetin 3-O-glucoside were mediated by selectively inhibiting the EGFR-mediated FAK, AKT, MEK1/2, and ERK1/2 signaling pathway. Combinatorial treatment with quercetin 3-O-glucoside plus gemcitabine showed the synergistic anti-migratory effect on epidermal growth factor-induced cell migration in human pancreatic cancer cell lines. These results suggest that quercetin 3-O-glucoside has potential for anti-metastatic therapy in human pancreatic cancer.
- Published
- 2015
33. Inhibition of highly pathogenic avian influenza (HPAI) virus by a peptide derived from vFLIP through its direct destabilization of viruses
- Author
-
Ho-Jin Moon, Jae-Hoon Kim, Won-Kyung Cho, Chamilani Nikapitiya, Hyun-Cheol Lee, Jong-Soo Lee, Ji-Eun Yoon, Jae U. Jung, Tae-Hwan Kim, Chul-Joong Kim, Min-Eun Park, and Jin Yeul Ma
- Subjects
0301 basic medicine ,Science ,viruses ,030106 microbiology ,Peptide ,Virus Replication ,medicine.disease_cause ,Antiviral Agents ,Article ,Virus ,Madin Darby Canine Kidney Cells ,Microbiology ,Viral Proteins ,03 medical and health sciences ,Dogs ,Orthomyxoviridae Infections ,Viral envelope ,Influenza A virus ,medicine ,Animals ,Lung ,Virus Release ,chemistry.chemical_classification ,Mice, Inbred BALB C ,Multidisciplinary ,biology ,virus diseases ,Vesiculovirus ,Viral Load ,Virus Internalization ,biology.organism_classification ,Survival Analysis ,Virology ,In vitro ,Influenza A virus subtype H5N1 ,Respiratory Syncytial Viruses ,Disease Models, Animal ,Treatment Outcome ,030104 developmental biology ,chemistry ,Vesicular stomatitis virus ,Medicine ,Oligopeptides ,Viral load - Abstract
The antiviral activities of synthesized Kα2-helix peptide, which was derived from the viral FLICE-like inhibitor protein (vFLIP) of Kaposi’s sarcoma-associated herpesvirus (KSHV), against influenza A virus (IAV) were investigated in vitro and in vivo, and mechanisms of action were suggested. In addition to the robust autophagy activity of the Kα2-helix peptide, the present study showed that treatment with the Kα2 peptide fused with the TAT peptide significantly inhibited IAV replication and transmission. Moreover, TAT-Kα2 peptide protected the mice, that were challenged with lethal doses of highly pathogenic influenza A H5N1 or H1N1 viruses. Mechanistically, we found that TAT-Kα2 peptide destabilized the viral membranes, depending on their lipid composition of the viral envelop. In addition to IAV, the Kα2 peptide inhibited infections with enveloped viruses, such as Vesicular Stomatitis Virus (VSV) and Respiratory Syncytial Virus (RSV), without cytotoxicity. These results suggest that TAT-Kα2 peptide is a potential antiviral agent for controlling emerging or re-emerging enveloped viruses, particularly diverse subtypes of IAVs.
- Published
- 2017
34. Prevalence, incidence, and associated factors of avascular necrosis in Korean patients with systemic lupus erythematosus: a nationwide epidemiologic study
- Author
-
Jee-Seon Shim, Jae-Hoon Kim, Sang Cheol Bae, Hye-Soon Lee, Young Bin Joo, Yoon-Kyoung Sung, and Eui Kyung Lee
- Subjects
Adult ,Male ,medicine.medical_specialty ,Databases, Factual ,Immunology ,Comorbidity ,Cohort Studies ,Young Adult ,Rheumatology ,Adrenal Cortex Hormones ,Risk Factors ,Internal medicine ,Republic of Korea ,Epidemiology ,Odds Ratio ,Prevalence ,medicine ,Humans ,Lupus Erythematosus, Systemic ,Immunology and Allergy ,Risk factor ,Aged ,Hypolipidemic Agents ,Retrospective Studies ,Lupus erythematosus ,business.industry ,Incidence ,Incidence (epidemiology) ,Osteonecrosis ,Hydroxychloroquine ,Retrospective cohort study ,Odds ratio ,Middle Aged ,medicine.disease ,Antirheumatic Agents ,Hypertension ,Physical therapy ,Regression Analysis ,Female ,business ,Immunosuppressive Agents ,Cohort study ,medicine.drug - Abstract
Avascular necrosis (AVN) is one of the most frequent types of organ damage in systemic lupus erythematosus (SLE). However, little is currently known about the epidemiology of AVN in SLE patients. The aim of this study was to estimate the prevalence and incidence of AVN in Korean patients with SLE based on National Health Insurance (NHI) claims data and to determine the risk factors for AVN among SLE patients. This study was conducted using the 2006-2010 data of 25,358 SLE patients from the NHI program. AVN cases were defined as those with at least one diagnosis of AVN. The prevalence was calculated by dividing the number of AVN cases by the number of SLE cases in the same year. The annual incidence was calculated by dividing the number of incident AVN cases by the number of SLE-prevalent cases not previously diagnosed with AVN. Patients who developed AVN in 2008-2010 were compared with SLE patients who did not develop AVN to identify any risk factors. The prevalence of AVN among SLE patients (2006-2010) was 31.5-34.2 per 1,000 persons and was similar in all the years studied. The incidence per 1,000 persons of AVN among SLE patients was 8.6 [95 % confidence interval (95 % CI) 6.9-10.3] in 2008, 9.8 (95 % CI 8.0-11.6) in 2009, and 8.4 (95 % CI 6.8-10.0) in 2010. Regression analysis indicated that taking an oral corticosteroid [odds ratio (OR) 2.12, 95 % CI 1.39-3.23] or an intravenous corticosteroid (OR 1.5, 95 % CI 1.2-1.89) was significantly associated with AVN. In addition, AVN was associated with use of immunosuppressive agents (OR 2.12, 95 % CI 1.66-2.72), hydroxychloroquine (OR 1.4, 95 % CI 1.09-1.81), and lipid-lowering agents (OR 1.78, 95 % CI 1.24-2.57) among the prescribed medications, and with hypertension (OR 1.39, 95 % CI 1.08-1.79) among the comorbidities. The prevalence and incidence of AVN among SLE patients, which were 31.5-34.2 and 8.4-9.8 per 1,000 persons, respectively, may be representative of the entire population of symptomatic AVN patients with SLE in Korea. AVN is associated with the use of corticosteroids, immunosuppressants, hydroxychloroquine, lipid-lowering agents, and with hypertension. Studies of large, prospective cohorts are needed to confirm these results.
- Published
- 2014
35. Selective RF Fingerprint Scanning for Large-Scale Wi-Fi Positioning Systems
- Author
-
Jae-Hoon Kim and Woon-Young Yeo
- Subjects
Positioning system ,Computer Networks and Communications ,business.industry ,Computer science ,Strategy and Management ,Real-time computing ,Fingerprint (computing) ,Computer security ,computer.software_genre ,Hardware and Architecture ,Received signal strength indication ,Data integrity ,Location-based service ,Global Positioning System ,Mobile telephony ,business ,Mobile device ,computer ,Information Systems - Abstract
Rapid growth in mobile communication and the proliferation of smartphones have drawn significant attention to location-based services (LBSs). One of the most important factors in the vitalization of LBSs is the accurate position estimation of a mobile device. The traditional global positioning system method has a critical weakness in terms of its limited availability, e.g., in indoor environments. The Wi-Fi positioning system is an attractive method that measures received signal strength indication data from all Wi-Fi access points (APs) and stores them in a huge database in the form of a radio frequency (RF) fingerprint map. Because of the millions of APs in urban areas, RF fingerprints are easily contaminated and transfigured. For this reason, a frequent rescanning of fingerprints is essential for fingerprint data integrity. However, rescanning fingerprints for an entire area requires a considerable amount of cost and effort. Therefore, we present a selective fingerprint rescan method for efficient fingerprint map management. All fingerprint data used in the developed test-bed are harvested from actual radio fingerprint measurements taken throughout Seoul, Korea, to demonstrate the practical usefulness of the proposed methodology.
- Published
- 2014
36. Design optimization of slender elastic beam with initial twist using genetic algorithms and finite element analysis
- Author
-
Jun Hwan Jang and Jae-Hoon Kim
- Subjects
Coupling ,Blade (geometry) ,business.industry ,Rotor (electric) ,Mechanical Engineering ,Stiffness ,Structural engineering ,Finite element method ,law.invention ,Matrix (mathematics) ,Mechanics of Materials ,law ,Genetic algorithm ,medicine ,medicine.symptom ,business ,Beam (structure) ,Mathematics - Abstract
This paper aims to obtain the optimal composite slender beam design for a rotor blade. The cross-sectional dimensions are considered as design variables. The objective is to optimize the box beam to attain a target matrix of stiffness values and maximum elastic coupling. The optimization process is performed using a genetic algorithm (GA), associated with a variational asymptotic method for the structural analysis. The stiffness control of arbitrary, complex section under some design condition is performed in composite beam where the geometrically nonlinear characteristic of the structure is considered. The objective function is defined as the weight, strength and fatigue life. The laminate thicknesses are to be determined optimally by defining a design index comprising a weighted average of the objective functions and determining the minimum.
- Published
- 2014
37. Effect of Plasma Deposition Using Low-Power/Non-thermal Atmospheric Pressure Plasma on Promoting Adhesion of Composite Resin to Enamel
- Author
-
Chang-Keun Kim, Jae-Hoon Kim, Bae-Hyeock Chun, Byeong-Hoon Cho, Geum-Jun Han, and Sung-No Chung
- Subjects
Materials science ,Enamel paint ,Bond strength ,Scanning electron microscope ,Weibull modulus ,General Chemical Engineering ,Composite number ,Atmospheric-pressure plasma ,General Chemistry ,Adhesion ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Contact angle ,stomatognathic system ,visual_art ,visual_art.visual_art_medium ,Composite material - Abstract
This study investigated the effect of monomer deposition through a low-power, non-thermal atmospheric pressure plasma (NT-APP) on adhesion of resin composite to enamel and its durability. The adhesion of resin composite to enamel and its durability were compared using micro-shear bond strength (MSBS) tests, with or without monomer deposition and before or after thermocycling (TC). The bond strength data were interpreted using Weibull analysis. Hydrophilicities of treated ceramic surfaces were compared with contact angle measurements. Surface characterization was performed with a Fourier transform infra-red spectrophotometer and X-ray photoelectron spectroscopy. The fracture mode at the interface was evaluated using a stereomicroscope and a scanning electron microscope. The plasma polymer deposition of benzene and 1,3-butadiene using the low-power NT-APP improved the MSBS of resin composite to enamel (p
- Published
- 2014
38. Micro deformation of automobile hood in dipping process using stiffness
- Author
-
Naksoo Kim, C. Oh, Nam Hwi Hur, and Jae-Hoon Kim
- Subjects
Reverse engineering ,Engineering ,business.industry ,Process (computing) ,Stiffness ,Structural engineering ,Deformation (meteorology) ,computer.software_genre ,Automotive Engineering ,medicine ,Material constants ,medicine.symptom ,business ,Spot welding ,computer ,Analysis method ,Reliability (statistics) - Abstract
Technicians have been going through trial-and-error processes to solve very small or micro deformation on automobile hood during the painting process. In order to establish a systematic improvement procedure which can replace the time-consuming trial-and-error method to reduce defects, an accurate analysis of how micro deformation occurs during the painting process is needed. We have utilized a stiffness scanning method in automobile hood and reverse engineering to build up a reliable and accurate structural analysis and measurement procedures. We measured the load-stroke data at critical locations on automobile hood through stiffness scanning to determine material constants closest to the measurement by assuming several critical hood parts, such as sealer inside the hood, hemming part, spot weld part, and other uncertain joints, as virtual elastic materials. After setting the difference between analytical and measured load-stroke data as an objective function, we computed and minimized it by using the response surface method and partial differentiation of the object function. As a result, by obtaining the reliability was over 91%, which showed a strong correlation between analysis and measured results. By comparing the actual strain measured in real painting lines with calculated strain, we confirmed the validity of our structural analysis method. It was concluded that the proper analysis tool could be utilized in determination of optimal locations of supports during the painting process.
- Published
- 2014
39. A 2-stage hybrid position estimation framework in RF fingerprint WPS
- Author
-
Jae-Hoon Kim, Hyeong-In Choi, Doo Seok Lee, and Suk-Yon Kang
- Subjects
Positioning system ,Computer Networks and Communications ,business.industry ,Computer science ,Fingerprint (computing) ,Wi-Fi positioning system ,computer.software_genre ,Fingerprint ,Embedded system ,Location-based service ,Mobile telephony ,Pattern matching ,Data mining ,Electrical and Electronic Engineering ,business ,Mobile device ,computer ,Information Systems - Abstract
The rapid growth of mobile communication and the proliferation of smart phones have drawn significant attention to Location Based Services (LBS). One of the most important factors in the vitalization of LBS is the accurate position estimation of a mobile device. By focusing on an access points (AP) probabilistic existence, we develop an AP distribution map and a new position estimating framework. The developed approach can significantly enhance a radio fingerprint-based Wi-Fi Positioning System, especially in terms of the algorithms and data management. In comparison with existing approaches of fingerprint pattern matching algorithms, we achieve an improved performance in terms of both the average and deviation of the estimation error. All fingerprint data used in the developed test-bed are harvested from actual radio fingerprint measurements taken throughout Seoul, Korea. This demonstrates the practical usefulness of the proposed methodology.
- Published
- 2014
40. Effectiveness of papaverine cisternal irrigation for cerebral vasospasm after aneurysmal subarachnoid hemorrhage and measurement of biomarkers
- Author
-
Young Soo Kim, Jae Min Kim, Yong Ko, Dong-Won Kim, Hyeong-Joong Yi, and Jae Hoon Kim
- Subjects
Adult ,Male ,medicine.medical_specialty ,Subarachnoid hemorrhage ,Neurology ,Immunoglobulins ,Dermatology ,Aneurysm, Ruptured ,Young Adult ,Cerebral vasospasm ,Fibrinolytic Agents ,Papaverine ,medicine ,Humans ,Vasospasm, Intracranial ,Prospective Studies ,cardiovascular diseases ,Therapeutic Irrigation ,Prospective cohort study ,Aged ,Aged, 80 and over ,Biologic marker ,Urokinase ,business.industry ,Cell Adhesion Molecule-1 ,Vasospasm ,General Medicine ,Middle Aged ,Subarachnoid Hemorrhage ,Intercellular Adhesion Molecule-1 ,medicine.disease ,Urokinase-Type Plasminogen Activator ,nervous system diseases ,Psychiatry and Mental health ,Treatment Outcome ,Anesthesia ,cardiovascular system ,Female ,Neurology (clinical) ,business ,Cell Adhesion Molecules ,Biomarkers ,medicine.drug - Abstract
Cisternal irrigation with thrombolytic agents was used to prevent post-SAH vasospasm, but its role remained inconclusive. To verify effectiveness of papaverine (PPV) in preventing vasospasm, we studied relationship between inflammatory biologic markers and vasospasm. This prospective study included 121 patients with clipped anterior circulation aneurysms that had ruptured, and 372 control patients. Patients were divided into three groups according to cisternal irrigation method: simple drain, papaverine group, and urokinase (UK) group. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were determined in CSF and serum on days 3 and 7 after SAH. The PPV group showed similar incidence of vasospasm with UK group, but lower incidence than the simple drain group. The levels of ICAM-1 and VCAM-1 were significantly higher in the SAH group than in the control group. CSF and serum levels were more elevated on day 7 than day 3, and the degree of elevation were more marked when measured in the CSF than in the serum. However, there was no statistical difference between measured levels of ICAM-1 and VCAM-1, and vasospasm development. PPV cisternal irrigation was similarly effective as UK at preventing vasospasm. Although neither PPV nor UK irrigation could reduce the concentration of adhesion molecules compared with simple drain, we found levels of ICAM-1 and VCAM-1 were specifically elevated in the CSF. Therefore, further research should focus on anti-inflammation as a therapeutic target against cerebral vasospasm and on the CSF as the optimum place where such inflammatory action practically brought about.
- Published
- 2013
41. A Giant Congenital Melanocytic Nevus Associated with Neurocutaneous Melanosis
- Author
-
Soo Jung Kim, Changyoung Yoo, Byung-chul Son, and Jae Hoon Kim
- Subjects
medicine.medical_specialty ,Neurocutaneous melanosis ,business.industry ,Congenital melanocytic nevus ,Medicine ,Radiology, Nuclear Medicine and imaging ,Neurology (clinical) ,Neurosurgery ,business ,medicine.disease ,Dermatology ,Neuroradiology - Published
- 2013
42. Synthesis and characterization of photosensitive poly(imide sulfonates) for fuel cell application
- Author
-
Jae Hoon Kim, Hui Liu, Pushan Wen, Xiang-Dan Li, and Myong-Hoon Lee
- Subjects
chemistry.chemical_compound ,Chalcone ,Monomer ,Membrane ,Materials science ,chemistry ,Polymer chemistry ,Synthetic membrane ,Copolymer ,Moiety ,General Materials Science ,Imide ,Polyimide - Abstract
The novel sulfonated polyimide membranes were successfully synthesized by thermal imidization with monomers of 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 4,4′-diaminodiphenyl ether-2,2′-disulfonic acid (SODA) and 3,3′-diaminochalcone (3DAC). Photosensitive chalcone moiety was introduced to the main chain of copolymers, and the photocrosslinking of resulting copolymer in aqueous electrolyte was attempted. A series of sulfonated copolyimide precursors containing chalcone functional groups in the main chain were prepared with different sulfonation degrees by controlling the molar ratio of SODA, 6FDA and 3DAC. The polymer membranes were prepared from these sulfonated aromatic precursors by solution casting and subsequent thermal imidization. The crosslinking with UV irradiation was attempted in the presence or absence of distilled water. The characterizations of the resulting membrane such as the ion-exchange capacity, water absorption and ionic conductivity were performed with respect to the copolymer compositions and the photocrosslinking conditions.
- Published
- 2013
43. Production of recombinant miraculin protein using transgenic citrus cell suspension culture system
- Author
-
Seong Beom Jin, Song-I Han, Dong-Sun Lee, Hyeon Jin Sun, Adnan Al Bachchu, Sung Jin Chung, Jae-Hoon Kim, Jongwoo Lee, Key Zung Riu, Jeong Hun Yun, and Kyung Whan Boo
- Subjects
Signal peptide ,Somatic embryogenesis ,Miraculin ,Transgene ,fungi ,Organic Chemistry ,food and beverages ,Biology ,General Biochemistry, Genetics and Molecular Biology ,law.invention ,Transformation (genetics) ,Biochemistry ,law ,Callus ,Botany ,Recombinant DNA ,Citrus × sinensis - Abstract
Miraculin gene containing the N-terminal signal peptide was introduced into navel orange (Citrus sinensis Osb. var. brasiliensis Tanaka) callus cells by Agrobacterum-mediated transformation. Transgenic somatic embryos were screened on the shoot induction medium containing 25 mg hygromycin L−1. Citrus callus cells were reproduced from the green color somatic embryos on the callus reproduction medium. The obtained transgenic cells were cultured in Murashige and Tucker’s liquid medium containing 50 g sucrose L−1 in a shaking incubator. Similar to the native miraculin, the secreted recombinant miraculin protein formed a disulfide-linked dimer and retained taste-modifying activity. The stability of recombinant protein expression was confirmed over nine generations of callus. This production system can be an excellent alternative for producing various recombinant proteins as well as miraculin.
- Published
- 2013
44. Sequential deposition of hexamethyldisiloxane and benzene in non-thermal plasma adhesion to dental ceramic
- Author
-
Chang-Keun Kim, Sung-No Chung, Geum-Jun Han, Bae-Hyeock Chun, Byeong-Hoon Cho, and Jae-Hoon Kim
- Subjects
chemistry.chemical_classification ,Hexamethyldisiloxane ,Materials science ,Polymers and Plastics ,Double bond ,Bond strength ,General Chemical Engineering ,Organic Chemistry ,Adhesion ,Plasma polymerization ,Contact angle ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,visual_art ,Polymer chemistry ,Materials Chemistry ,visual_art.visual_art_medium ,Ceramic ,Wetting - Abstract
According to the types of dental ceramic, various surface treatment techniques have been tried for adhesive cementation, but each treatment has its shortcomings. A simple and universal surface treatment for intraoral and chair-side adhesion promotion is needed for resin cements. This study investigated whether hexamethyldisiloxane (HMDSO) and benzene, when deposited using a low-power non-thermal atmospheric pressure dielectric barrier discharge jet, were effective precursor monomers in dental ceramic adhesion. Their effect on adhesion was evaluated with shear bond strength test (SBS), contact angle measurement, X-ray photoelectron spectroscopy, and Fourier transform infra-red spectrophotometer in an attenuated total reflectance mode. The bonded interfaces and fractured surfaces were evaluated using a scanning electron microscope. Plasma polymerization of HMDSO resulted in formation of a siloxane network (Si2 peak), but its surface hydrophobicity hindered adhesive wetting. Additional deposition of benzene onto the HMDSO-coated ceramic surface increased the C1 peak, which partly corresponded to the C=C double bonds, and the hydrophilic peaks (C-O, C=O and O-C=O bonds). Benzene deposition itself improved the adhesion between the ceramic and the overlying adhesive through the chemical interaction of C=C double bonds and the increased hydrophilic groups. Additional deposition of HMDSO before benzene mediated the chemical adhesion of benzene to the ceramic surface and led to an additional increase of bond strength. Plasma polymerization of benzene and HMDSO/benzene increased the bond strength of composite resin to dental ceramic by improving wettability and adaptation with hydrophilic ether, carbonyl and ester groups, and chemical bonding with active species, such as C=C double bonds and silanol groups. Open image in new window
- Published
- 2013
45. Evaluation of the CORDEX-Africa multi-RCM hindcast: systematic model errors
- Author
-
Bruce Hewitson, Chris A. Mattmann, Christopher Lennard, Colin Jones, C. E. Goodale, Alice Favre, Andrew F. Hart, Daniel J. Crichton, Christopher Jack, Duane E. Waliser, Grigory Nikulin, Jae-Hoon Kim, and Paul Zimdars
- Subjects
Wet season ,Atmospheric Science ,Meteorology ,Cloud cover ,Climatology ,Reference data (financial markets) ,Hindcast ,Environmental science ,Climate model ,Precipitation ,Subtropics ,Forcing (mathematics) - Abstract
Monthly-mean precipitation, mean (TAVG), maximum (TMAX) and minimum (TMIN) surface air temperatures, and cloudiness from the CORDEX-Africa regional climate model (RCM) hindcast experiment are evaluated for model skill and systematic biases. All RCMs simulate basic climatological features of these variables reasonably, but systematic biases also occur across these models. All RCMs show higher fidelity in simulating precipitation for the west part of Africa than for the east part, and for the tropics than for northern Sahara. Interannual variation in the wet season rainfall is better simulated for the western Sahel than for the Ethiopian Highlands. RCM skill is higher for TAVG and TMAX than for TMIN, and regionally, for the subtropics than for the tropics. RCM skill in simulating cloudiness is generally lower than for precipitation or temperatures. For all variables, multi-model ensemble (ENS) generally outperforms individual models included in ENS. An overarching conclusion in this study is that some model biases vary systematically for regions, variables, and metrics, posing difficulties in defining a single representative index to measure model fidelity, especially for constructing ENS. This is an important concern in climate change impact assessment studies because most assessment models are run for specific regions/sectors with forcing data derived from model outputs. Thus, model evaluation and ENS construction must be performed separately for regions, variables, and metrics as required by specific analysis and/or assessments. Evaluations using multiple reference datasets reveal that cross-examination, quality control, and uncertainty estimates of reference data are crucial in model evaluations.
- Published
- 2013
46. Hydrogenated monolayer graphene with reversible and tunable wide band gap and its field-effect transistor
- Author
-
Han-Koo Lee, Sang Jin Kim, Byung Hee Hong, Jongill Hong, Sang-Hoon Kim, Byung Cheol Park, Jae Hoon Kim, Jangyup Son, and Soogil Lee
- Subjects
Multidisciplinary ,Materials science ,Graphene ,Band gap ,Science ,Transistor ,Wide-bandgap semiconductor ,General Physics and Astronomy ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,General Biochemistry, Genetics and Molecular Biology ,0104 chemical sciences ,law.invention ,law ,Monolayer ,Field-effect transistor ,0210 nano-technology ,Bilayer graphene ,Graphene nanoribbons - Abstract
Graphene is currently at the forefront of cutting-edge science and technology due to exceptional electronic, optical, mechanical, and thermal properties. However, the absence of a sizeable band gap in graphene has been a major obstacle for application. To open and control a band gap in functionalized graphene, several gapping strategies have been developed. In particular, hydrogen plasma treatment has triggered a great scientific interest, because it has been known to be an efficient way to modify the surface of single-layered graphene and to apply for standard wafer-scale fabrication. Here we show a monolayer chemical-vapour-deposited graphene hydrogenated by indirect hydrogen plasma without structural defect and we demonstrate that a band gap can be tuned as wide as 3.9 eV by varying hydrogen coverage. We also show a hydrogenated graphene field-effect transistor, showing that on/off ratio changes over three orders of magnitude at room temperature., The absence of a band gap in graphene hinders its use in electronics. Here, the authors open a band gap as large as 3.9 electronvolts in graphene grown by chemical vapour deposition by treating it in hydrogen plasma, and then use this material to create a room temperature field- effect transistor.
- Published
- 2016
47. Expression of fibroblast growth factor receptor family members is associated with prognosis in early stage cervical cancer patients
- Author
-
Jae Hoon Kim, Joon-Yong Chung, Stephen M. Hewitt, Byoung-Gie Kim, and Chel Hun Choi
- Subjects
musculoskeletal diseases ,0301 basic medicine ,Oncology ,medicine.medical_specialty ,Pathology ,Adenosquamous carcinoma ,Uterine Cervical Neoplasms ,Kaplan-Meier Estimate ,General Biochemistry, Genetics and Molecular Biology ,Image analysis ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Internal medicine ,medicine ,Humans ,Survival analysis ,Neoplasm Staging ,Medicine(all) ,Uterine cervical neoplasm ,Cervical cancer ,Biochemistry, Genetics and Molecular Biology(all) ,business.industry ,Research ,Fibroblast growth factor receptor 1 ,Cancer ,General Medicine ,Fibroblast growth factor receptor 4 ,Middle Aged ,Prognosis ,medicine.disease ,Immunohistochemistry ,Receptors, Fibroblast Growth Factor ,Fibroblast growth factor receptor ,stomatognathic diseases ,030104 developmental biology ,030220 oncology & carcinogenesis ,Multivariate Analysis ,Female ,business - Abstract
Background The oncogenic role of the fibroblast growth factor receptor (FGFR) has been recognized in a number of different cancer types. However, the prognostic significance of FGFRs has not been elucidated yet in cervical cancer. In the present study, we investigate the expression of FGFRs and their prognostic value in cervical cancer patients. Methods FGFR1, FGFR2, FGFR3, and FGFR4 expression was determined by immunohistochemistry in conjunction with quantitative digital image analysis of 336 formalin-fixed, paraffin-embedded cervical cancer tissues and 61 normal cervical tissues, as well as NCI60 cell microarray. Subsequently, the association between clinicopathological characteristics and patient survival was assessed. Results FGFRs proteins were differentially expressed in the NCI60 cell line panel and showed considerable correlation between protein and mRNA expression. The expression of FGFR1, FGFR2, and FGFR4 were higher in cancer tissues than in normal tissues, whereas the expression of FGFR3 was higher in normal tissues. FGFR1 was highly expressed in adeno-/adenosquamous carcinoma (P = 0.020), while FGFR2, FGFR3, and FGFR4 expression were more prominent in squamous cell carcinoma (P
- Published
- 2016
48. Erratum to: Population attributable risks of modifiable reproductive factors for breast and ovarian cancers in Korea
- Author
-
Keun-Young Yoo, Aesun Shin, Hai Rim Shin, Sei Hyun Ahn, Boyoung Park, Kyu-Won Jung, Dong Young Noh, Tae Jin Kim, Jae Weon Kim, Ji Yeob Choi, Sue K. Park, Sohee Park, Byoung Gie Kim, Daehee Kang, Yong Man Kim, Sokbom Kang, Yohwan Yeo, and Jae Hoon Kim
- Subjects
Adult ,0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Population ,Breast Neoplasms ,03 medical and health sciences ,0302 clinical medicine ,Pregnancy ,Risk Factors ,Internal medicine ,Republic of Korea ,Genetics ,medicine ,Humans ,education ,Reproductive History ,Ovarian Neoplasms ,education.field_of_study ,business.industry ,Reproduction ,Cancer ,Reproductive Factors ,medicine.disease ,030104 developmental biology ,030220 oncology & carcinogenesis ,Female ,Erratum ,business ,Contraceptives, Oral ,Maternal Age - Abstract
Breast and ovarian cancers are predominant female cancers with increasing prevalence. The purpose of this study was to estimate the population attributable risks (PARs) of breast and ovarian cancer occurrence based on the relative risks (RRs) of modifiable reproductive factors and population-specific exposure prevalence.The PAR was calculated by using the 1990 standardized prevalence rates, the 2010 national cancer incidence with a 20 year lag period, the meta-analyzed RRs from studies conducted in the Korean population for breast cancer, and the meta-analyzed RRs from a Korean epithelial ovarian cancer study and a prior meta-analysis, and ovarian cancer cohort results up to 2012. For oral contraceptive and hormone replacement therapy use, we did not consider lag period.The summary PARs for modifiable reproductive factors were 16.7% (95% CI 15.8-17.6) for breast cancer (2404 cases) and 81.9% (95% CI 55.0-100.0) for ovarian cancer (1579 cases). The modifiable reproductive factors included pregnancy/age at first birth (8.0%), total period of breastfeeding (3.1%), oral contraceptive use (5.3%), and hormone replacement therapy use (0.3%) for breast cancer and included breastfeeding experience (2.9%), pregnancy (1.2%), tubal ligation (24.5%), and oral contraceptive use (53.3%) for ovarian cancer.Despite inherent uncertainties in the risk factors for breast and ovarian cancers, we suggest that appropriate long-term control of modifiable reproductive factors could reduce breast and ovarian cancer incidences and their related burdens by 16.7% and 81.9%, respectively.
- Published
- 2016
49. Nonlinear modeling and coupled characteristic of composite structure with complex curvature
- Author
-
Jun Hwan Jang and Jae-Hoon Kim
- Subjects
business.industry ,Mechanical Engineering ,Composite number ,Flexural rigidity ,Structural engineering ,Curvature ,Industrial and Manufacturing Engineering ,Nonlinear system ,Deflection (engineering) ,Bending stiffness ,Electrical and Electronic Engineering ,business ,Beam (structure) ,Mathematics ,Stiffness matrix - Abstract
The paper presents an experimental verification for calculating coupled stiffness matrix in complex curvature composite structure. The results of the analytical procedure using Variational Asymptotic Beam Sectional Analysis also indicate that the calculation of 2-D, beam, cross-sectional properties can then be incorporated into and 1-D beam analysis expressed coupled stiffness matrix. This paper presents the 2-D cross-sectional analysis of active anisotropic beams. Comparison between the analytical and experimental results shows that the proposed analytical procedure can provide an accurate and efficient prediction of the both deflection and flexural stiffness of multilayer composite slender structure. Verified comparison results can be used to efficiently design accurate complex slender structure properties for preliminary design and optimization.
- Published
- 2012
50. A profile of expressed sequence tags in newly developing leaves of Aralia elata seem
- Author
-
Doseung Lee, Jin-Man Lee, Key Zung Riu, Seong Beom Jin, Kyung Hwan Boo, Jae-Hoon Kim, Seong-Cheol Kim, Somi Kim Cho, and Dong-Sun Lee
- Subjects
Genetics ,Expressed sequence tag ,Contig ,cDNA library ,food and beverages ,Plant Science ,Horticulture ,Biology ,Aralia elata ,Homology (biology) ,Protein sequencing ,Complementary DNA ,Gene ,Biotechnology - Abstract
A cDNA library was constructed from the newly developed young leaves of Aralia elata Seem, and a total of 2,755 cDNAs were partially sequenced. Sequences with high quality greater than 150 bp after trimming vector and ambiguous sequences resulted in 2,689 ESTs. These ESTs were clustered into 2,010 unigenes consisting of 376 contigs with two or more ESTs and 1,634 singletons. A homology search with BLASTX against the NCBI database identified 1,256 (63%) unigenes homologous to proteins of known or putative function, 350 (17%) genes assumed as proteins with unknown function, and 404 (20%) unigenes with no significant match to any protein sequence, including sequences with matches greater than the E value of −105 in the NCBI database. The expression level of each gene was analyzed based on the number of cDNA clones in each contig composed of at least 10 ESTs. The most abundant gene identified was acid phosphatase. The genes related to chlorophyll a-b binding protein, elongation factor 1-alpha, ribulose 1,5-bisphosphate carboxylase small subunit and cyclophilin were also plentiful. The 1,259 unigenes matched with proteins of known or putative function were classified into a functional category using the MIPS BLAST program and 616 unigenes were assigned to putative biochemical functions. Furthermore, five, sixteen and twelve unigenes in our EST set were assumed as proteins involved in squalene synthesis, cytochrome P450 and glycosyltransferase, respectively. These genes should be further explored for their involvement in the saponin biosynthesis pathway in A. elata Seem.
- Published
- 2012
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.