167 results on '"Youngsoo Kim"'
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2. Adaptive affine homogenization method for Visco-hyperelastic composites with imperfect interface
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Youngsoo Kim, Jiyoung Jung, Sangryun Lee, Issam Doghri, and Seunghwa Ryu
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Applied Mathematics ,Modeling and Simulation - Published
- 2022
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3. The absence of attrition in a war of attrition under complete information
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H. Dharma Kwon, Youngsoo Kim, and George Georgiadis
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TheoryofComputation_MISCELLANEOUS ,Physics::Physics and Society ,Computer Science::Computer Science and Game Theory ,Economics and Econometrics ,Class (set theory) ,FOS: Economics and business ,Fragility ,Complete information ,Economics - Theoretical Economics ,FOS: Mathematics ,medicine ,Canonical model ,Economics ,Attrition ,Mathematics - Optimization and Control ,Randomness ,Probability (math.PR) ,ComputingMilieux_PERSONALCOMPUTING ,TheoryofComputation_GENERAL ,Contrast (statistics) ,medicine.disease ,Mathematical Finance (q-fin.MF) ,Markov perfect equilibrium ,Quantitative Finance - Mathematical Finance ,Optimization and Control (math.OC) ,Theoretical Economics (econ.TH) ,Mathematical economics ,Mathematics - Probability ,Finance - Abstract
We consider a two-player game of war of attrition under complete information. It is well-known that this class of games admits equilibria in pure, as well as mixed strategies, and much of the literature has focused on the latter. We show that if the players' payoffs whilst in "war" vary stochastically and their exit payoffs are heterogeneous, then the game admits Markov Perfect equilibria in pure strategies only. This is true irrespective of the degree of randomness and heterogeneity, thus highlighting the fragility of mixed-strategy equilibria to a natural perturbation of the canonical model. In contrast, when the players' flow payoffs are deterministic or their exit payoffs are homogeneous, the game admits equilibria in pure and mixed strategies., Comment: 36 pages
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- 2022
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4. Proteomic Discovery of Prognostic Protein Biomarkers for Persisting Problems after Mild Traumatic Brain Injury
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Min-Yong Lee, Minsoo Son, Hyun Haeng Lee, Min-Gu Kang, Seo Jung Yun, Han Gil Seo, Youngsoo Kim, and Byung-Mo Oh
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- 2023
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5. S-scheme assisted Cu2O/ZnO flower-shaped heterojunction catalyst for breakthrough hydrogen evolution by water splitting
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Seog Joon Yoon, Taeseong Kim, Misook Kang, Hyerim Park, Namgyu Son, Byung Hyun Park, and Youngsoo Kim
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Photocurrent ,Materials science ,Hydrogen ,Renewable Energy, Sustainability and the Environment ,Band gap ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Heterojunction ,Condensed Matter Physics ,Catalysis ,Fuel Technology ,chemistry ,Chemical engineering ,Photocatalysis ,Water splitting ,Hydrogen production - Abstract
Zinc and copper are considered as excellent metals for oxidation and reducibility, respectively. This study aims to obtain a redox-coupled composite semiconductor, wherein oxides of Zn and Cu were obtained and junctioned, for application as a photocatalyst in hydrogen production. To create a large number of activated sites on the catalyst's surface, the morphologies of the catalysts were controlled and several angular parts were formed. During the junction process, Cu2O and ZnO particles were controlled in cubic and starfish shapes, respectively, and the structure of the junctioned Cu2O/ZnO composite was similar to that of a chrysanthemum flower. Kubelka–Munk and Mott–Schottky plots demonstrated that ZnO and Cu2O have band gaps of 3.2 and 1.9 eV, respectively, and they are n- and p-type semiconductors, respectively. The TRPL and IMVS, as well as the photocurrent density and IMPS, confirmed that the recombination between electrons and holes in the junctioned Cu2O/ZnO particles was very slow, and effective charge separation was achieved. As a result, the amount of hydrogen generated from the junction catalyst was significantly higher than that generated from the single catalysts. In particular, the accumulated amount of evolved hydrogen after 10 h in the 2Cu2O/1ZnO junction catalyst was 2089.5 μmol. Results obtained from spin-trapping ESR experiments suggest that the charge-transfer mechanism in the redox-coupled 2Cu2O/1ZnO junction catalyst follows the S-scheme with a stronger reducing power.
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- 2021
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6. Nanotechnology and machine learning enable circulating tumor cells as a reliable biomarker for radiotherapy responses of gastrointestinal cancer patients
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Michael J. Poellmann, Jiyoon Bu, Stanley Liu, Andrew Z. Wang, Steven N. Seyedin, Chandrikha Chandrasekharan, Heejoo Hong, YoungSoo Kim, Joseph M. Caster, and Seungpyo Hong
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Electrochemistry ,Biomedical Engineering ,Biophysics ,General Medicine ,Biotechnology - Published
- 2023
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7. Continuous glucose monitoring reveals glycemic variability and hypoglycemia after vertical sleeve gastrectomy in rats
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Ki-Suk Kim, Diana M. Farris, Daniel E. Michele, Alfor G. Lewis, Youngsoo Kim, Matthew J. Sorensen, Robert T. Kennedy, Randy J. Seeley, Nadejda Bozadjieva, Steven E. Whitesall, Darleen A. Sandoval, and Simon S. Evers
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Blood Glucose ,Male ,0301 basic medicine ,endocrine system diseases ,OGTT, oral glucose tolerance test ,medicine.medical_treatment ,Exendin 9-39 ,Ex9, exendin 9-39 ,DPP-4, dipeptidyl peptidase-4 ,Gastroenterology ,0302 clinical medicine ,Medicine ,Glycemic variability ,Continuous glucose monitoring ,GIP, gastric inhibitory polypeptide ,MAG, mean absolute glucose ,PBH, post–bariatric surgery hypoglycemia ,3. Good health ,Current medication ,Original Article ,Epi, epinephrine ,Postprandial Hypoglycemia ,lcsh:Internal medicine ,medicine.medical_specialty ,Sleeve gastrectomy ,Rat model ,030209 endocrinology & metabolism ,Hypoglycemia ,Glucagon-Like Peptide-1 Receptor ,03 medical and health sciences ,VSG, vertical sleeve gastrectomy ,Gastrectomy ,Internal medicine ,PYY, peptide YY ,2DG, 2-deoxyglucose ,Animals ,CGM, continuous glucose monitoring ,lcsh:RC31-1245 ,Molecular Biology ,Glycemic ,business.industry ,RYGB, Roux-en-Y gastric bypass ,nutritional and metabolic diseases ,Cell Biology ,Glucose Tolerance Test ,medicine.disease ,Post–bariatric surgery hypoglycemia ,Rats ,Blockade ,Disease Models, Animal ,030104 developmental biology ,Vertical sleeve gastrectomy ,business ,NE, norepinephrine ,GLP-1R, glucagon-like peptide-1 receptor - Abstract
Objective Post–bariatric surgery hypoglycemia (PBH) is defined as the presence of neuroglycopenic symptoms accompanied by postprandial hypoglycemia in bariatric surgery patients. Recent clinical studies using continuous glucose monitoring (CGM) technology revealed that PBH is more frequently observed in vertical sleeve gastrectomy (VSG) patients than previously recognized. PBH cannot be alleviated by current medication. Therefore, a model system to investigate the mechanism and treatment is required. Methods We used CGM in a rat model of VSG and monitored the occurrence of glycemic variability and hypoglycemia in various meal conditions for 4 weeks after surgery. Another cohort of VSG rats with CGM was used to investigate whether the blockade of glucagon-like peptide-1 receptor (GLP-1R) signaling alleviates these symptoms. A mouse VSG model was used to investigate whether the impaired glucose counterregulatory system causes postprandial hypoglycemia. Results Like in humans, rats have increased glycemic variability and hypoglycemia after VSG. Postprandial hypoglycemia was specifically detected after liquid versus solid meals. Further, the blockade of GLP-1R signaling raises the glucose nadir but does not affect glycemic variability. Conclusions Rat bariatric surgery duplicates many features of human post–bariatric surgery hypoglycemia including postprandial hypoglycemia and glycemic variability, while blockade of GLP-1R signaling prevents hypoglycemia but not the variability., Highlights • VSG causes glycemic variability during ad lib feeding condition. • Single liquid meal ingestion causes post-VSG hypoglycemia. • Blockade of GLP-1 receptor prevents post-VSG hypoglycemia.
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- 2020
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8. Design a Well-Dispersed Ag-Based/Cofe2o4–Cnt Catalyst for Hydrogen Production Via Nabh4 Hydrolysis
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Mohamed Abdelsalam, Yoon Taeho, Youngsoo KiM, and Yasser Mostafa
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- 2022
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9. Investment in the common good: free rider effect and the stability of mixed strategy equilibria
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H. Dharma Kwon and Youngsoo Kim
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History ,Polymers and Plastics ,Management Science and Operations Research ,Business and International Management ,Industrial and Manufacturing Engineering ,Computer Science Applications - Abstract
The free rider problem is widely observed in investments in the common good. For example, if Best Buy offers corporate social responsibility (CSR) programs, such as recycling, tech training, and supplier audit, at its own expense, other firms in the industry can benefit from these programs at no cost (i.e., they become the free riders). Such a free rider effect often manifests itself as a mixed strategy equilibrium, in which potential investors unnecessarily delay their investments. The article “Investment in the common good: Free rider effect and the stability of mixed strategy equilibria” finds that recurring investment opportunities can be a major driver of delays in investment in the common good. It also shows that sufficient heterogeneity in investment cost among potential investors can alleviate the free rider effect. Therefore, the policy makers may try to facilitate investments in public goods (e.g., CSR activities) through some form of selective benefits to potential investors.
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- 2022
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10. The role of CCL2, CCL7, ICAM-1, and VCAM-1 in interaction of endothelial cells and natural killer cells
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Hye, Won Jun, Hong, Kyung Lee, Ik, Ho Na, Su, Jeong Lee, Kihyeon, Kim, Geuno, Park, Hyung, Sook Kim, Dong, Ju Son, Youngsoo, Kim, Jin, Tae Hong, and Sang-Bae, Han
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Killer Cells, Natural ,Pharmacology ,Tumor Necrosis Factor-alpha ,Immunology ,Humans ,Vascular Cell Adhesion Molecule-1 ,Endothelial Cells ,Immunology and Allergy ,Endothelium, Vascular ,Chemokine CCL7 ,Intercellular Adhesion Molecule-1 ,Cells, Cultured ,Chemokine CCL2 - Abstract
Natural killer (NK) cell-based therapy has been studied for the treatment of patients with cancers, but the inadequate infiltration of NK cells into solid tumors remains a big challenge to its clinical application. In this study, we examined the interaction between NK cells and endothelial cells, which might play a major role in NK cell homing to solid tumors. We found that endothelial cells were activated by TNF-α and IL-1β, which were produced by tumor-associated CD11b
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- 2022
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11. Chemical inhibition of TRAF6-TAK1 axis as therapeutic strategy of endotoxin-induced liver disease
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Song-Hee, Kim, Seung-Il, Baek, Jihye, Jung, Eung-Seok, Lee, Younghwa, Na, Bang Yeon, Hwang, Yoon-Seok, Roh, Jin Tae, Hong, Sang-Bae, Han, and Youngsoo, Kim
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Lipopolysaccharides ,TNF Receptor-Associated Factor 6 ,Pharmacology ,Caspase 3 ,Tumor Necrosis Factor-alpha ,Liver Diseases ,NF-kappa B ,Galactosamine ,General Medicine ,MAP Kinase Kinase Kinases ,Receptors, Tumor Necrosis Factor ,Endotoxins ,Ligases ,Mice, Inbred C57BL ,Toll-Like Receptor 4 ,Transcription Factor AP-1 ,Mice ,Animals ,Cytokines ,Protein Kinases ,Ubiquitins ,Adaptor Proteins, Signal Transducing ,Signal Transduction - Abstract
The liver is exposed to gut-derived bacterial endotoxin via portal circulation, and recognizes it through toll-like receptor 4 (TLR4). Endotoxin lipopolysaccharide (LPS) stimulates the self-ubiquitination of ubiquitin ligase TRAF6, which is linked to scaffold with protein kinase TAK1 for auto-phosphorylation and subsequent activation. TAK1 activity is a signal transducer in the activating pathways of transcription factors NF-κB and AP-1 for production of various cytokines. Here, we hypothesized that TRAF6-TAK1 axis would be implicated in endotoxin-induced liver disease. Following exposure to endotoxin LPS, TLR4-mediated phosphorylation of TAK1 and transcription of cell-death cytokine TNF-α were triggered in Kupffer cells but not in hepatocytes as well as TNF receptor-mediated and caspase-3-executed apoptosis was occurred in D-galactosamine (GalN)-sensitized hepatocytes under co-culture with Kupffer cells. Treatment with pyridinylmethylene benzothiophene (PMBT) improved endotoxin LPS-induced hepatocyte apoptosis in GalN-sensitized C57BL/6 mice via suppressing NF-κB- and AP-1-regulated expression of TNF-α in Kupffer cells, and rescued the mice from hepatic damage-associated bleeding and death. As a mechanism, PMBT directly inhibited Lys 63-linked ubiquitination of TRAF6, and mitigated scaffold assembly between TRAF6 and the TAK1-activator adaptors TAB1 and TAB2 complex in Kupffer cells. Thereby, PMBT interrupted TRAF6 ubiquitination-induced activation of TAK1 activity in the TLR4-mediated signal cascade leading to TNF-α production. However, PMBT did not directly affect the apoptotic activity of TNF-α on GalN-sensitized hepatocytes. Finally, we propose chemical inhibition of TRAF6-TAK1 axis in Kupffer cells as a strategy for treating liver disease due to gut-derived endotoxin or Gram-negative bacterial infection.
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- 2022
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12. Improved incrementally affine homogenization method for viscoelastic-viscoplastic composites based on an adaptive scheme
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Jiyoung Jung, Youngsoo Kim, Sangryun Lee, Issam Doghri, and Seunghwa Ryu
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Ceramics and Composites ,Civil and Structural Engineering - Published
- 2022
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13. Enhanced Potency of GalNAc-Conjugated Antisense Oligonucleotides in Hepatocellular Cancer Models
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A. Robert MacLeod, Youngsoo Kim, Noah Post, Thazha P. Prakash, Xiaokun Xiao, Stephanie Klein, Zhengfeng Yin, Joanna Schmidt, Tianyuan Zhou, Xiaolin Luo, and Minji Jo
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Acetylgalactosamine ,Carcinoma, Hepatocellular ,Gene Expression ,Asialoglycoprotein Receptor ,Conjugated system ,Cell Line ,ASOs ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Circulating tumor cell ,ASGR ,Drug Discovery ,Genetics ,medicine ,Animals ,Potency ,GalNAc conjugation ,HCC ,Molecular Biology ,Cells, Cultured ,030304 developmental biology ,Pharmacology ,Antitumor activity ,0303 health sciences ,Hepatocellular cancer ,Chemistry ,Liver Neoplasms ,Gene Transfer Techniques ,Oligonucleotides, Antisense ,medicine.disease ,digestive system diseases ,carbohydrates (lipids) ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Antisense oligonucleotides ,Cancer research ,Molecular Medicine ,Original Article ,Asialoglycoprotein receptor ,CTCs - Abstract
Antisense oligonucleotides (ASOs) are a novel therapeutic approach to target difficult-to-drug protein classes by targeting their corresponding mRNAs. Significantly enhanced ASO activity has been achieved by the targeted delivery of ASOs to selected tissues. One example is the targeted delivery of ASOs to hepatocytes, achieved with N-acetylgalactosamine (GalNAc) conjugation to ASO, which results in selective uptake by asialoglycoprotein receptor (ASGR). Here we have evaluated the potential of GalNAc-conjugated ASOs as a therapeutic approach to targeting difficult-to-drug pathways in hepatocellular carcinoma (HCC). The activity of GalNAc-conjugated ASOs was superior to that of the unconjugated parental ASO in ASGR (+) human HCC cells in vitro, but not in ASGR (−) cells. Both human- and mouse-derived HCC displayed reduced levels of ASGR, however, despite this, GalNAc-conjugated ASOs showed a 5- to 10-fold increase in potency in tumors. Systemically administered GalNAc-conjugated ASOs demonstrated both enhanced antisense activity and antitumor activity in the diethylnitrosamine-induced HCC tumor model. Finally, GalNAc conjugation enhanced ASO activity in human circulating tumor cells from HCC patients, demonstrating the potential of this approach in primary human HCC tumor cells. Taken together, these results provide a strong rationale for a potential therapeutic use of GalNAc-conjugated ASOs for the treatment of HCC., Kim et al. report that the activity of antisense oligonucleotides (ASOs) can be significantly enhanced in hepatocellular carcinoma (HCC) through conjugation with N-acetylgalactosamine (GalNAc), a ligand for asialoglycoprotein receptor (ASGR) expressed highly in hepatocytes, demonstrating the potential application of targeted delivery of ASOs to treat HCC.
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- 2019
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14. Synthesis of N-arylindazole-3-carboxamide and N-benzoylindazole derivatives and their evaluation against α-MSH-stimulated melanogenesis
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Jae-Kyung Jung, Youngsoo Kim, Sateesh Kumar Arepalli, Chaerim Lee, Heesoon Lee, and Kiho Lee
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Ortho position ,Indazoles ,Skin Neoplasms ,Stereochemistry ,medicine.drug_class ,Clinical Biochemistry ,Melanoma, Experimental ,Pharmaceutical Science ,Positive control ,Antineoplastic Agents ,Carboxamide ,Biochemistry ,Para position ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Cell Line, Tumor ,Drug Discovery ,medicine ,Animals ,Molecular Biology ,Dose-Response Relationship, Drug ,Molecular Structure ,Chemistry ,Organic Chemistry ,Arbutin ,alpha-MSH ,Polar effect ,Molecular Medicine - Abstract
We have designed and synthesized twenty-six N-arylindazole-3-carboxamide (3a-p) and N-benzoylindazole (6a-j) derivatives to discover with excellent inhibition activities of α-MSH-stimulated melanogenesis. In the bio evaluation studies of these compounds, we discovered eighteen compounds, out of twenty-six exhibited more potent inhibition than the positive control arbutin. From the SAR studies, we identified 3k and 6g as lead compounds which displayed almost 5 and 9 times more potent inhibition of α-MSH-stimulated melanogenesis respectively than the reference arbutin. It is also evident the presence of electron withdrawing group at para position (R3) for the compounds (3a-p) and presence of +M group at ortho position (R5) for the compounds (6a-j) were crucial for their excellent inhibition activities of α-MSH-stimulated melanogenesis.
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- 2019
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15. Influence of spear needle eccentricity on jet quality in micro Pelton turbine for power generation
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Dong Ho Shin, In Hyuk Jung, Jin Taek Chung, Youngsoo Kim, and Youhwan Shin
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Flow visualization ,Materials science ,Astrophysics::High Energy Astrophysical Phenomena ,020209 energy ,media_common.quotation_subject ,Nozzle ,02 engineering and technology ,Turbine ,Industrial and Manufacturing Engineering ,law.invention ,Physics::Fluid Dynamics ,020401 chemical engineering ,law ,0202 electrical engineering, electronic engineering, information engineering ,0204 chemical engineering ,Electrical and Electronic Engineering ,Eccentricity (behavior) ,Diffusion (business) ,Civil and Structural Engineering ,media_common ,Jet (fluid) ,Computer simulation ,Mechanical Engineering ,Building and Construction ,Injector ,Mechanics ,Pollution ,General Energy ,Physics::Accelerator Physics ,Astrophysics::Earth and Planetary Astrophysics - Abstract
The quality of the jet injected from a nozzle is one of the key factors that affects the performance of Pelton turbines. In this study, for the first time, experiments and numerical simulation were conducted to investigate the effect of the spear needle eccentricity on the jet flow in micro Pelton turbines. Results show that the eccentricity of the spear needle causes jet diffusion under low flow conditions and significantly increases the loss of the spear nozzle (injector). Furthermore, the increase in the eccentricity ratio causes extreme jet separation and jet diffusion, and the loss of the spear nozzle increases by 52% (from 453 W to 688 W) when the eccentricity ratio increases by 6%. Analysis of the results confirmed that the pressure deviation and jet velocity imbalance caused by eccentricity are the primary causes of jet diffusion. Furthermore, the results confirm that the eccentricity of the spear needle in the case of a low-capacity Pelton turbine has a significant effect on the jet quality. Thus, further studies on the eccentricity are required to improve the performance of the Pelton turbine.
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- 2019
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16. NF-κB inhibitory sesquiterpene lactones from Lebanese Laurus nobilis
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Hala Gali-Muhtasib, Hala Khalife, Bang Yeon Hwang, Jin Yong Song, Yang Hee Jo, Jong Hoon Ahn, Youngsoo Kim, Mi Kyeong Lee, and Ayman Turk
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Transcriptional activity ,Traditional medicine ,Lipopolysaccharide ,010405 organic chemistry ,Chemistry ,NF-κB ,Plant Science ,Magnolialide ,Sesquiterpene ,Inhibitory postsynaptic potential ,01 natural sciences ,Biochemistry ,food.food ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Laurus nobilis ,food ,Agronomy and Crop Science ,IC50 ,Biotechnology - Abstract
The leaves of Laurus nobilis, commonly called as bay leaves, have been traditionally used for the treatment of inflammatory symptoms. As a part of the research on the characterization of bioactive constituents from natural products, twenty one sesquiterpene lactones were isolated from the leaves of L. nobilis. Among them, laurenoperoxylides A (1) and B (2) were first reported in nature and sivosinolide (11), altissin (12), maroniolid (13) and 4α-hydroxy-guaia-10(14), 11(13)-diene-12,6α-olide (20) were first isolated from this plant. The anti-inflammatory activity of isolated compounds was evaluated by measuring their effects on the NF-κB transcriptional activity induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages cells. Among twenty one sesquiterpenes, 11-exo-methylenesantonin (9) exerted the most potent inhibition with an IC50 value of 4.0 μM. Santamarine (4), magnolialide (5) and zaluzanin D (18) also significantly inhibited NF-κB activity with IC50 values of
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- 2019
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17. Characterization of morphological changes of B16 melanoma cells under natural killer cell attack
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Gi Beom Ahn, Ji Sung Kim, Jieun Yun, Boyeong Kim, Yeo Jin Choi, Youngsoo Kim, Jin Tae Hong, Sang-Bae Han, Hyung Sook Kim, Hong Kyung Lee, and Eun Jae Park
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0301 basic medicine ,Myosin Light Chains ,medicine.medical_treatment ,Immunology ,Cell ,Melanoma, Experimental ,Natural killer cell ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Immunology and Allergy ,CD155 ,Pharmacology ,biology ,Chemistry ,Melanoma ,Immunotherapy ,medicine.disease ,Gene Expression Regulation, Neoplastic ,Killer Cells, Natural ,Mice, Inbred C57BL ,030104 developmental biology ,Cell killing ,medicine.anatomical_structure ,Granzyme ,030220 oncology & carcinogenesis ,Cancer cell ,biology.protein ,Cancer research - Abstract
Natural killer (NK) cell killing of melanoma cells involves perforin-mediated delivery of granzymes from NK cells to cancer cells; however, how melanoma cells die remains poorly characterized. Here, we examined the dying process of melanoma cells by using time-lapse imaging. Upon contact with NK cells, B16-F10 cells rounded and most of them showed membrane rupture (98 min); however, B16 parent cells showed writhing and delayed membrane rupture (235 min). This morphological difference depended on the expression levels of myosin regulatory light chain 9 (MYL9) but not activating ligands (CD112, CD155, Rae-1, and MULT-1), SPI, FasL, or PD-L1. Taken together, our data show that melanoma cells show two distinct types of morphological changes upon contact with NK cells and suggest that a strategy to decrease MYL9 expression by melanoma cells may improve the efficacy of NK cell–based immunotherapy.
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- 2019
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18. Subwavelength ultrasonic imaging via a harmonic resonant tunneling metalens
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Shin Hur, Hoyoon Jeon, Md. Anzan-Uz-Zaman, Youngsoo Kim, Muhammad A. Shah, Jinsik Kim, and Byung Chul Lee
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Condensed Matter Physics ,Civil and Structural Engineering - Published
- 2022
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19. Dimeric- and trimeric sesquiterpenes from the flower of Inula japonica
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Qinghao Jin, Youngsoo Kim, Jin Tae Hong, Hye Lim Lee, Bang Yeon Hwang, Jin Woo Lee, Mi Kyeong Lee, Jun Gu Kim, Hari Jang, Eun-Hee Kim, Wanying Wu, and Dongho Lee
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Lipopolysaccharides ,Inula japonica ,Stereochemistry ,Trimer ,Flowers ,Plant Science ,Horticulture ,Nitric Oxide ,Sesquiterpene ,01 natural sciences ,Biochemistry ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Cell Line, Tumor ,Ic50 values ,Animals ,Humans ,Molecular Biology ,Cell Proliferation ,Dose-Response Relationship, Drug ,biology ,010405 organic chemistry ,Anti-Inflammatory Agents, Non-Steroidal ,General Medicine ,Asteraceae ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,Cycloaddition ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,RAW 264.7 Cells ,chemistry ,Inula ,Drug Screening Assays, Antitumor ,Sesquiterpenes ,Two-dimensional nuclear magnetic resonance spectroscopy ,Human cancer - Abstract
An undescribed unusual sesquiterpene trimer and three sesquiterpene dimers were isolated from the flowers of Inula japonica. Their structures were elucidated by extensive analysis of 1D and 2D NMR spectroscopic data as well as HRESIMS data. Inulajaponicolide A has an undescribed carbon skeleton comprising of one xanthanolide and two guaianolide units with the linkage mode of C-11/C-3ʹ and C-11ʹ/C-1ʹʹ via a Diels-Alder cycloaddition reaction. Inulajaponicolides C and D exhibited moderate cytotoxic activity against A 549 and NCI-H460 human cancer cell lines with IC50 values ranging from 8.5 to 17.8 μM. Inulajaponicolides A-D and lineariifolianoid A possessed significant inhibitory potency against nitric oxide production in LPS-induced RAW264.7 cells with IC50 values ranging from 1.0 to 4.1 μM.
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- 2018
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20. Nitric oxide inhibitory constituents from Siegesbeckia pubescens
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Youngsoo Kim, Jun Gu Kim, Mi Kyeong Lee, Jin Tae Hong, Jin Woo Lee, Thi Phoung Linh Le, Bang Yeon Hwang, Hye Ryoung Hong, and Hari Jang
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Lipopolysaccharides ,Magnetic Resonance Spectroscopy ,Molecular Conformation ,Asteraceae ,Nitric Oxide ,Inhibitory postsynaptic potential ,01 natural sciences ,Biochemistry ,Nitric oxide ,Inhibitory Concentration 50 ,Mice ,chemistry.chemical_compound ,Drug Discovery ,Ic50 values ,Animals ,Organic chemistry ,Molecular Biology ,biology ,Plant Extracts ,010405 organic chemistry ,Chemistry ,Macrophages ,Organic Chemistry ,Siegesbeckia pubescens ,biology.organism_classification ,Terpenoid ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,RAW 264.7 Cells ,Diterpenes ,Sesquiterpenes ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Two new sesquiterpenoids (1 and 2) and a new ent-pimarane type diterpenoid (3), together with eighteen known compounds (4–21), were isolated from the whole plants of Siegesbeckia pubescens. The structures of the new compounds were determined on the basis of 1D-, 2D NMR and HRESIMS data. All compounds were evaluated for their inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages. Of these, highly oxygenated germacrane type sesquiterpenoids (1–2 and 13–14) showed significant inhibitory effects with IC50 values ranging from 3.9 to 16.8 μM.
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- 2018
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21. CXCR3-deficient natural killer cells fail to migrate to B16F10 melanoma cells
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Youngsoo Kim, Ju Young Kim, Jin Tae Hong, Ji Sung Kim, Hyung Sook Kim, Yeo Jin Choi, Eun Young Kim, Hong Kyung Lee, Jeong Eun Choi, Sang-Bae Han, Bo Ram Shin, and Eun Jae Park
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0301 basic medicine ,Chemokine ,Receptors, CXCR3 ,medicine.medical_treatment ,Immunology ,Cell ,Melanoma, Experimental ,Biology ,CCL2 ,CXCR3 ,CCL5 ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Animals ,Immunology and Allergy ,CXCL10 ,Mice, Knockout ,Pharmacology ,Immunotherapy ,Chemokine CXCL10 ,Killer Cells, Natural ,Mice, Inbred C57BL ,Chemotaxis, Leukocyte ,030104 developmental biology ,medicine.anatomical_structure ,Cancer cell ,Cancer research ,biology.protein ,030215 immunology - Abstract
Natural killer (NK) cells eliminate cancer cells in a contact-dependent manner. However, how NK cells find cancer cells remain unclear. Here, using time-lapse imaging, we investigated how individual NK cells migrate toward cancer cells. Although naïve B16F10 cancer cells produce low levels of chemokines, IFN-γ-treated B16F10 cells secreted high levels of CXCL10, low levels of CCL5, but did not secrete CCL2, CCL7, or CXCL12. Wild-type NK cells migrated well toward cancer cells and killed them, whereas NK cells deficient in CXCR3 did not. CXCR3-deficient NK cells also showed slower migration speed than did wild-type NK cells. Taken together, our data show that NK cells find cancer cells, at least in part, by sensing CXCL10 produced by cancer cells and suggest that a strategy to increase CXCL10 secretion by cancer cells may improve the efficacy of NK cell-based immunotherapy.
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- 2018
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22. Quantitative Proteomic Analysis Identifies AHNAK (Neuroblast Differentiation-associated Protein AHNAK) as a Novel Candidate Biomarker for Bladder Urothelial Carcinoma Diagnosis by Liquid-based Cytology
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Kyung Eun Lee, Kyung Chul Moon, Youngsoo Kim, Hyeyoon Kim, In Ae Park, Bo Bae Shim, Joonho Park, Kwangsoo Kim, Ji Young Kim, Jongmin Woo, Han Suk Ryu, Ji Hye Moon, Hyebin Lee, Hyeyeon Kim, and Dohyun Han
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Male ,Proteomics ,0301 basic medicine ,Tissue Fixation ,Proteome ,Cytological Techniques ,Human Protein Atlas ,Biology ,Biochemistry ,Workflow ,Analytical Chemistry ,03 medical and health sciences ,Formaldehyde ,Biomarkers, Tumor ,medicine ,Humans ,RNA, Messenger ,Molecular Biology ,Aged ,Urine cytology ,Aged, 80 and over ,Paraffin Embedding ,Bladder cancer ,medicine.diagnostic_test ,Proteomic Profiling ,Research ,Membrane Proteins ,Reproducibility of Results ,Middle Aged ,medicine.disease ,Neoplasm Proteins ,030104 developmental biology ,ROC Curve ,Urinary Bladder Neoplasms ,Liquid-based cytology ,Cancer research ,Biomarker (medicine) ,Female ,Urothelium ,Neuroblast differentiation - Abstract
Cytological examination of urine is the most widely used noninvasive pathologic screen for bladder urothelial carcinoma (BLCA); however, inadequate diagnostic accuracy remains a major challenge. We performed mass spectrometry-based proteomic analysis of urine samples of ten patients with BLCA and ten paired patients with benign urothelial lesion (BUL) to identify ancillary proteomic markers for use in liquid-based cytology (LBC). A total of 4,839 proteins were identified and 112 proteins were confirmed as expressed at significantly different levels between the two groups. We also performed an independent proteomic profiling of tumor tissue samples where we identified 7,916 proteins of which 758 were differentially expressed. Cross-platform comparisons of these data with comparative mRNA expression profiles from The Cancer Genome Atlas identified four putative candidate proteins, AHNAK, EPPK1, MYH14 and OLFM4. To determine their immunocytochemical expression levels in LBC, we examined protein expression data from The Human Protein Atlas and in-house FFPE samples. We further investigated the expression of the four candidate proteins in urine cytology samples from two independent validation cohorts. These analyses revealed AHNAK as a unique intracellular protein differing in immunohistochemical expression and subcellular localization between tumor and non-tumor cells. In conclusion, this study identified a new biomarker, AHNAK, applicable to discrimination between BLCA and BUL by LBC. To our knowledge, the present study provides the first identification of a clinical biomarker for LBC based on in-depth proteomics.
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- 2018
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23. Comparative proteomic analysis of human malignant ascitic fluids for the development of gastric cancer biomarkers
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Hyeyoon Kim, Youngsoo Kim, Minsoo Son, Hark Kyun Kim, Jonghwa Jin, Dohyun Han, Seong Ho Kong, and Hyeyeon Kim
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Liver Cirrhosis ,Proteomics ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Cirrhosis ,Proteome ,Clinical Biochemistry ,Neoplasm Seeding ,Peptide Mapping ,Sensitivity and Specificity ,Cohort Studies ,03 medical and health sciences ,Peritoneal Neoplasm ,0302 clinical medicine ,Stomach Neoplasms ,Ascites ,Biomarkers, Tumor ,Pepsinogen C ,medicine ,Ascitic Fluid ,Humans ,Biomarker discovery ,Peritoneal Neoplasms ,Neoplasm Staging ,Principal Component Analysis ,business.industry ,Gene Expression Profiling ,Stomach ,Cancer ,General Medicine ,medicine.disease ,Neoplasm Proteins ,Gene Expression Regulation, Neoplastic ,Gene Ontology ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer biomarkers ,medicine.symptom ,business ,Cell Adhesion Molecules - Abstract
Objectives Malignant ascites is a sign of peritoneal seeding, which is one of the most frequent forms of incurable distant metastasis . Because the development of malignant ascites is associated with an extremely poor prognosis, determining whether it resulted from peritoneal seeding has critical clinical implications in diagnosis, choice of treatment, and active surveillance. At present, the molecular characterizations of malignant ascites are especially limited in case of gastric cancer. We aimed to identify malignant ascites-specific proteins that may contribute to the development of alternative methods for diagnosis and therapeutic monitoring and also increase our understanding of the pathophysiology of peritoneal seeding. Design & methods First, comprehensive proteomic strategies were employed to construct an in-depth proteome of ascitic fluids. Label-free quantitative proteomic analysis was subsequently performed to identify candidates that can differentiate between malignant ascitic fluilds of gastric cancer patients from benign ascitic fluids. Finally, two candidate proteins were verified by ELISA in 84 samples with gastric cancer or liver cirrhosis . Results Comprehensive proteome profiling resulted in the identification of 5347 ascites proteins. Using label-free quantification , we identified 299 proteins that were differentially expressed in ascitic fluids between liver cirrhosis and stage IV gastric cancer patients. In addition, we identified 645 proteins that were significantly expressed in ascitic fluids between liver cirrhosis and gastric cancer patients with peritoneal seeding. Finally, Gastriscin and Periostin that can distinguish malignant ascites from benign ascites were verified by ELISA. Conclusions This study identified and verified protein markers that can distinguish malignant ascites with or without peritoneal seeding from benign ascites. Consequently, our results could be a significant resource for gastric cancer research and biomarker discovery in the diagnosis of malignant ascites.
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- 2018
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24. Identification of novel 2-benzyl-1-indanone analogs as interleukin-5 inhibitors
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Youngsoo Kim, Pulla Reddy Boggu, Jungsuk Cho, and Sang-Hun Jung
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0301 basic medicine ,Pharmacology ,Dose-Response Relationship, Drug ,Molecular Structure ,Stereochemistry ,Chemistry ,Organic Chemistry ,Substituent ,General Medicine ,Inhibitory postsynaptic potential ,Ring (chemistry) ,Cell Line ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Indans ,Drug Discovery ,Animals ,Interleukin-5 ,Interleukin 5 - Abstract
A novel series of 2-benzyl-1-indanone analogs were investigated as IL-5 inhibitory activity. Among the synthesized compounds, 7-(cyclohexylmethoxy)-2-(4-hydroxybenzyl)-2,3-dihydro-1H-inden-1-one (7s, 100.0% inhibition at 30 μM, IC50 = 4.0 μM), and 7-(cyclohexylmethoxy)-2-(3-hydroxybenzyl)-2,3-dihydro-1H-inden-1-one (7t, 95.0% inhibition at 30 μM, IC50 = 6.0 μM) showed the best inhibitory activity against IL-5. The 2-benzyl-1-indanone analogs showed moderate to strong IL-5 inhibitory activity. Especially, hydroxyl (HBD/HBA) substituent at position 3 or 4 on phenyl ring B showed potent IL-5 inhibition. Additionally, the bulky hydrophobic cyclohexylmethoxy group at position 7 of the 1-indanone ring is favorable for the inhibitory activity.
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- 2018
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25. Melanogenesis inhibitory pregnane glycosides from Cynanchum atratum
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Youngsoo Kim, Sang-Hun Jung, Jin Tae Hong, Cheong Yong Yun, Xiang Hua Han, Qinghao Jin, Mi Kyeong Lee, Bang Yeon Hwang, Dongho Lee, Jin Woo Lee, and Chul Lee
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0301 basic medicine ,Clinical Biochemistry ,Melanoma, Experimental ,Molecular Conformation ,Pharmaceutical Science ,Cynanchum ,Fractionation ,Plant Roots ,Biochemistry ,Melanin ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Line, Tumor ,Drug Discovery ,Humans ,Structure–activity relationship ,Glycosides ,Molecular Biology ,Cell Proliferation ,Melanins ,chemistry.chemical_classification ,Dose-Response Relationship, Drug ,biology ,Plant Extracts ,Cell growth ,Organic Chemistry ,Pregnane ,Glycoside ,Pregnanes ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,030104 developmental biology ,chemistry ,Molecular Medicine ,Drug Screening Assays, Antitumor ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Bioassay-guided fractionation of the methanolic extract from the roots of Cynanchum atratum has resulted in the isolation of three new pregnane glycosides (1-3) along with four known compounds (4-7). Their structures were identified by analysis of the spectroscopic data including extensive 2D NMR. All of the isolates were evaluated for their potential to inhibit the melanin production in α-melanocyte stimulating hormone (α-MSH)-activated B16 melanoma cells. Of these, compounds 4-7 dose-dependently inhibited the melanin production with the IC50 values ranging from 4 μM to 33 μM.
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- 2018
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26. CoS@TiO2 S-scheme heterojunction photocatalyst for hydrogen production from photoinduced water splitting
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Sang Woo Joo, Seyeon Kim, Taeseong Kim, Misook Kang, Youngsoo Kim, and Hyerim Park
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Materials science ,Renewable Energy, Sustainability and the Environment ,Strategy and Management ,Nanoparticle ,Heterojunction ,Building and Construction ,Cobalt sulfide ,Industrial and Manufacturing Engineering ,Catalysis ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Titanium dioxide ,Photocatalysis ,Water splitting ,General Environmental Science ,Hydrogen production - Abstract
To synthesize durable catalysts, cobalt sulfide (CoS) microsheet particles are woven into a polyhedral cage shape to prevent dissolution and light corrosion during photochemical reactions. Titanium dioxide (TiO2) nanoparticles with excellent stability against water and light are used to enclose the cage. The surface of the dodecahedral CoS particle is positively charged, and the surface of the spherical TiO2 particles is negatively charged, resulting in a core–shell shaped xCoS@yTiO2 heterojunction particle. The xCoS@yTiO2 heterojunction catalyst has a stronger ability to absorb visible light and greater photocatalytic hydrogen evolution activity than pure TiO2 or CoS catalysts: When lactic acid is used as an electronic sacrificial agent, the hydrogen production of 1CoS@2TiO2 reaches 1945 μmol g−1 for 10 h, and the catalytic activities are 114.4 and 13.2 times those of CoS and TiO2, respectively. Spin-trapping ESR results reveal that charge transfer in the core–shell shaped xCoS@yTiO2 heterojunction follows the S-scheme mechanism. The excellent catalytic activity of the core–shell shaped xCoS@yTiO2 heterojunction catalyst is because of its favorable bandgap location for water splitting, higher photocurrent density, lower photoluminescence, and having strong redox sites. These factors ultimately delay the recombination of photo-induced electron/hole pairs and, as a result, high catalytic efficiency is stably maintained up to the fifth recycling test.
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- 2021
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27. The antiviral enzyme viperin inhibits cholesterol biosynthesis
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E. Neil G. Marsh, Ayesha M. Patel, James Windak, Robert T. Kennedy, Youngsoo Kim, Keerthi Sajja, Alexey I. Nesvizhskii, Timothy J. Grunkemeyer, Soumi Ghosh, and Venkatesha Basrur
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0301 basic medicine ,DAVID, Database for Annotation, Visualization and Integrated Discovery ,Biochemistry ,Cell membrane ,radical SAM enzyme ,Intramolecular Transferases ,Lipid raft ,biology ,Chemistry ,ddhCTP, 3’-deoxy-3’,4’-didehydro-CTP ,Transfection ,SAINT, Significance Analysis of INTeractome ,Cell biology ,Cholesterol ,medicine.anatomical_structure ,viperin, Virus Inhibitory Protein, Endoplasmic Reticulum-associated, Interferon iNducible ,Viperin ,cholesterol regulation ,viperin ,Research Article ,FPPS, farnesyl pyrophosphate synthase ,Protein Binding ,Oxidoreductases Acting on CH-CH Group Donors ,Cytidine Triphosphate ,BIBB 515, (1-(4-chlorobenzoyl)-4-((4-(2-oxazolin-2-yl) benzylidene))piperidine) ,Antiviral Agents ,ER, endoplasmic reticulum ,03 medical and health sciences ,Downregulation and upregulation ,medicine ,Humans ,IFN, interferon ,Molecular Biology ,BHT, 2,6-di-tert-butyl-4-methylphenol ,PEI, polyethyleneimine ,HMGR, 3-hydroxy-3-methylglutaryl CoA reductase ,030102 biochemistry & molecular biology ,Endoplasmic reticulum ,HEK 293 cells ,LS, lanosterol synthase ,Proteins ,Cell Biology ,squalene monooxygenase ,HEK293T, human embryonic kidney 293T ,Biosynthetic Pathways ,TBS, Tris-buffered saline ,HEK293 Cells ,030104 developmental biology ,biology.protein ,interactome analysis ,UPLC, ultra performance LC ,RSV, respiratory syncytial virus ,SM, squalene monooxygenase ,lanosterol synthase ,TRAF6, TNF receptor–associated factor 6 ,Lanosterol synthase - Abstract
Many enveloped viruses bud from cholesterol-rich lipid rafts on the cell membrane. Depleting cellular cholesterol impedes this process and results in viral particles with reduced viability. Viperin (Virus Inhibitory Protein, Endoplasmic Reticulum-associated, Interferon iNducible) is an endoplasmic reticulum membrane-associated enzyme that exerts broad-ranging antiviral effects, including inhibiting the budding of some enveloped viruses. However, the relationship between viperin expression and the retarded budding of virus particles from lipid rafts on the cell membrane is unclear. Here, we investigated the effect of viperin expression on cholesterol biosynthesis using transiently expressed genes in the human cell line human embryonic kidney 293T (HEK293T). We found that viperin expression reduces cholesterol levels by 20% to 30% in these cells. Following this observation, a proteomic screen of the viperin interactome identified several cholesterol biosynthetic enzymes among the top hits, including lanosterol synthase (LS) and squalene monooxygenase (SM), which are enzymes that catalyze key steps in establishing the sterol carbon skeleton. Coimmunoprecipitation experiments confirmed that viperin, LS, and SM form a complex at the endoplasmic reticulum membrane. While coexpression of viperin was found to significantly inhibit the specific activity of LS in HEK293T cell lysates, coexpression of viperin had no effect on the specific activity of SM, although did reduce SM protein levels by approximately 30%. Despite these inhibitory effects, the coexpression of neither LS nor SM was able to reverse the viperin-induced depletion of cellular cholesterol levels, possibly because viperin is highly expressed in transfected HEK293T cells. Our results establish a link between viperin expression and downregulation of cholesterol biosynthesis that helps explain viperin's antiviral effects against enveloped viruses.
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- 2021
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28. Synthesis, biological evaluation, and metabolic stability of chlorogenic acid derivatives possessing thiazole as potent inhibitors of α-MSH-stimulated melanogenesis
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Mayavan Viji, Hyeju Jo, Seung-Yong Seo, Heesoon Lee, Jin Tae Hong, Jae Young Lim, Minho Choi, Kiho Lee, Jae-Kyung Jung, Jaeuk Sim, Yuanyuan Zhou, Wun Jae Kim, Jeongtae Rhee, and Youngsoo Kim
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0301 basic medicine ,Stereochemistry ,Clinical Biochemistry ,Catechols ,Pharmaceutical Science ,Inhibitory postsynaptic potential ,01 natural sciences ,Biochemistry ,Inhibitory Concentration 50 ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,Chlorogenic acid ,Cell Line, Tumor ,Drug Discovery ,Animals ,Humans ,Thiazole ,Molecular Biology ,Biological evaluation ,Melanins ,Catechol ,010405 organic chemistry ,Organic Chemistry ,Metabolic stability ,0104 chemical sciences ,Thiazoles ,030104 developmental biology ,Liver ,chemistry ,alpha-MSH ,Dioxolane ,Microsomes, Liver ,Molecular Medicine ,Chlorogenic Acid - Abstract
A series of catechol and dioxolane analogs containing thiazole CGA derivatives have been synthesized and evaluated for their inhibitory activity against α-MSH. The inhibitory activity was improved by replacing an α,β-unsaturated carbonyl of previously reported caffeamides with thiazole motif. Surprisingly, compound 7d , one of the derivatives of dioxolane analogs, displayed the most potent inhibitory activity with an IC 50 of 0.90 μM. Further studies on metabolic stability and bioactivation potential were also accomplished.
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- 2017
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29. Improvement of step-climbing capability of a new mobile robot RHyMo via kineto-static analysis
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Jongwon Kim, Seungmin Jung, Hwa Soo Kim, Dongkyu Choi, and Youngsoo Kim
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0209 industrial biotechnology ,Engineering ,business.industry ,Mechanical Engineering ,Bioengineering ,Mobile robot ,02 engineering and technology ,Kinematics ,Static analysis ,01 natural sciences ,Computer Science Applications ,Moment (mathematics) ,020901 industrial engineering & automation ,Mechanics of Materials ,Control theory ,0103 physical sciences ,Trajectory ,Climb ,Torque ,Center of mass ,business ,010301 acoustics ,Simulation - Abstract
This study presents the improvement of step-climbing capability of a new mobile robot called as RHyMo via kineto-static analysis. To this end, the kinematic analysis of the RHyMo is first performed to obtain the trajectory of its center of mass (CM) when it climbs up a step. Based on this CM trajectory, the linear/angular speeds and accelerations of its links are sequentially calculated. Different from the quasi-static analysis, the linear/angular accelerations are combined with the dynamic equations describing the force and moment equilibriums of RHyMo climbing the step, which are optimally solved by introducing the concept of the required friction coefficient in this study. This kineto-static analysis is repeatedly performed by changing the contact angle between the front track of RHyMo and the ground in order to minimize the torque required to climb the step. The simulations with different contact angles are carried out and then, the experiments using the RHyMo are performed, which can demonstrate that the trend of measured motor current is similar to that simulated by the kineto-static analysis and moreover, the step-climbing capability of the RHyMo is significantly improved by reducing the required motor currents by virtue of the kineto-static analysis.
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- 2017
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30. Novel analogs of N-acylhydroxyethylaminomethyl-4H-chromen-4-one scaffold as IL-5 inhibitors
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Pulla Reddy Boggu, Hyun-Sun Yang, Sang-Hun Jung, Youngsoo Kim, Eeda Venkateswararao, and Vinay K. Sharma
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0301 basic medicine ,Carbamate ,Stereochemistry ,medicine.medical_treatment ,Clinical Biochemistry ,Pharmaceutical Science ,Ring (chemistry) ,01 natural sciences ,Biochemistry ,Cell Line ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,chemistry.chemical_compound ,Amide ,Drug Discovery ,N-acylhydroxyethylaminomethyl-4H-chromen-4-one ,medicine ,Animals ,Structure–activity relationship ,Chromans ,Molecular Biology ,Cell Proliferation ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,0104 chemical sciences ,030104 developmental biology ,Polar effect ,Urea ,Molecular Medicine ,Interleukin-5 - Abstract
A number of N -acyl substituted hydroxyethylaminomethyl-4 H -chromen-4-ones 6a – u were prepared and evaluated for their IL-5 inhibitory activity. Among them, the compound 6r (95.0% inhibition at 30 µM, IC 50 = 10.0 µM, C log P = 4.1549) showed most potent inhibitory activity. The structure activity relationship revealed that the bulkier or hydrophobic substituents at urea, carbamate or amide group resulted in good inhibitory activity against IL-5. Moreover, electron donating group at phenyl ring ( 6g and 6s ) is much more active than electron withdrawing group ( 6f ). Finally, replacement of cyclohexylmethoxy group at 5 th position of ring A with bulky aliphatic substituents resulted in the loss of activity.
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- 2017
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31. Loss of Parkin reduces inflammatory arthritis by inhibiting p53 degradation
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Min Jong Song, Young Wan Ham, Mi Hee Park, Sang-Bae Han, Youngsoo Kim, Dae Hwan Kim, Jin Tae Hong, Dong Ju Son, Yu Yeon Jung, and Hye Lim Lee
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p53 ,Lipopolysaccharides ,Male ,0301 basic medicine ,Parkin ,Arthritis ,Ubiquitination ,Inflammatory arthritis ,Clinical Biochemistry ,Nitric Oxide Synthase Type II ,Biochemistry ,Arthritis, Rheumatoid ,Mice ,Ubiquitin ,lcsh:QH301-705.5 ,lcsh:R5-920 ,biology ,Chemistry ,NF-kappa B ,Up-Regulation ,Nitric oxide synthase ,medicine.symptom ,lcsh:Medicine (General) ,Research Paper ,Protein Binding ,medicine.medical_specialty ,Ubiquitin-Protein Ligases ,Mice, Transgenic ,Inflammation ,03 medical and health sciences ,Downregulation and upregulation ,Internal medicine ,medicine ,Animals ,Humans ,Cell Nucleus ,Organic Chemistry ,medicine.disease ,NFKB1 ,nervous system diseases ,Disease Models, Animal ,HEK293 Cells ,RAW 264.7 Cells ,030104 developmental biology ,Endocrinology ,lcsh:Biology (General) ,Cyclooxygenase 2 ,Proteolysis ,Immunology ,biology.protein ,Tumor Suppressor Protein p53 - Abstract
Parkin is associated with various inflammatory diseases, including Parkinson's disease (PD) and rheumatoid arthritis (RA). However, the precise role of Parkin in RA is unclear. The present study addressed this issue by comparing the development of RA between non-transgenic (non-Tg) mice and PARK2 knockout (KO) mice. We found that cyclooxygenase-2 and inducible nitric oxide synthase expression and nuclear factor-κB activity were reduced but p53 activation was increased in PARK2 KO as compared to non-Tg mice. These effects were associated with reduced p53 degradation. Parkin was found to interact with p53; however, this was abolished in Parkin KO mice, which prevented p53 degradation. Treatment of PARK2 KO mice with p53 inhibitor increased Parkin expression as well as inflammation and RA development while decreasing nuclear p53 translocation, demonstrating that PARK2 deficiency inhibits inflammation in RA via suppression of p53 degradation. These results suggest that RA development may be reduced in PD patients. Keywords: Parkin, Arthritis, p53, Ubiquitination
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- 2017
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32. Prediction of Response to Sorafenib in Hepatocellular Carcinoma: A Putative Marker Panel by Multiple Reaction Monitoring-Mass Spectrometry (MRM-MS)
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Eun Ju Cho, Young Youn Cho, Yoon Jun Kim, Youngsoo Kim, Sungyoung Lee, Yuri Cho, Dong Hyeon Lee, Taesung Park, Injun Yeo, Su Jong Yu, Jung Hwan Yoon, Jeong Hoon Lee, Jongsoo Jun, and Hyunsoo Kim
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Male ,Proteomics ,0301 basic medicine ,Oncology ,Biochemistry ,Mass Spectrometry ,Analytical Chemistry ,Medicine ,Precision Medicine ,Aged, 80 and over ,Receptors, Scavenger ,Standard treatment ,Liver Neoplasms ,Hazard ratio ,Technological Innovation and Resources ,Middle Aged ,Scavenger Receptors, Class B ,Sorafenib ,Treatment Outcome ,Hepatocellular carcinoma ,Female ,medicine.drug ,Adult ,Niacinamide ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Antineoplastic Agents ,Placebo ,03 medical and health sciences ,Antigens, Neoplasm ,Internal medicine ,Biomarkers, Tumor ,Carcinoma ,Humans ,Molecular Biology ,Survival analysis ,Aged ,Glycoproteins ,Retrospective Studies ,business.industry ,Phenylurea Compounds ,medicine.disease ,Survival Analysis ,Confidence interval ,030104 developmental biology ,Endocrinology ,Immunoglobulin J-Chains ,Apoptosis Regulatory Proteins ,Carrier Proteins ,business - Abstract
Sorafenib is the only standard treatment for unresectable hepatocellular carcinoma (HCC), but it provides modest survival benefits over placebo, necessitating predictive biomarkers of the response to sorafenib. Serum samples were obtained from 115 consecutive patients with HCC before sorafenib treatment and analyzed by multiple reaction monitoring-mass spectrometry (MRM-MS) and ELISA to quantify candidate biomarkers. We verified a triple-marker panel to be predictive of the response to sorafenib by MRM-MS, comprising CD5 antigen-like (CD5L), immunoglobulin J (IGJ), and galectin-3-binding protein (LGALS3BP), in HCC patients. This panel was a significant predictor (AUROC > 0.950) of the response to sorafenib treatment, having the best cut-off value (0.4) by multivariate analysis. In the training set, patients who exceeded this cut-off value had significantly better overall survival (median, 21.4 months) than those with lower values (median, 8.6 months; p = 0.001). Further, a value that was lower than this cutoff was an independent predictor of poor overall survival [hazard ratio (HR), 2.728; 95% confidence interval (CI), 1.312–5.672; p = 0.007] and remained an independent predictive factor of rapid progression (HR, 2.631; 95% CI, 1.448–4.780; p = 0.002). When applied to the independent validation set, levels of the cut-off value for triple-marker panel maintained their prognostic value for poor clinical outcomes. On the contrast, the triple-marker panel was not a prognostic factor for patients who were treated with transarterial chemoembolization (TACE). The discriminatory signature of a triple-marker panel provides new insights into targeted proteomic biomarkers for individualized sorafenib therapy.
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- 2017
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33. Pre-Opening Price Indications and Market Quality: Evidence from NYSE Rule 48
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Kee H. Chung, Chairat Chuwonganant, and Youngsoo Kim
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- 2019
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34. Equilibrium Selection in the War of Attrition Under Complete Information
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H. Dharma Kwon, Youngsoo Kim, and George Georgiadis
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TheoryofComputation_MISCELLANEOUS ,Physics::Physics and Society ,Computer Science::Computer Science and Game Theory ,History ,Class (set theory) ,Polymers and Plastics ,ComputingMilieux_PERSONALCOMPUTING ,TheoryofComputation_GENERAL ,medicine.disease ,Industrial and Manufacturing Engineering ,Fragility ,Markov perfect equilibrium ,Equilibrium selection ,Complete information ,Canonical model ,Economics ,medicine ,Attrition ,Business and International Management ,Mathematical economics ,Randomness - Abstract
We consider a two-player game of war of attrition under complete information. It is well- known that this class of games admits equilibria in pure, as well as mixed strategies, and much of the literature has focused on the latter. We show that if the players’ payoffs whilst in “war” vary stochastically and their exit payoffs are heterogeneous, then the game admits Markov Perfect equilibria in pure strategies only. This is true irrespective of the degree of randomness and heterogeneity, thus highlighting the fragility of mixed-strategy equilibria to a natural perturbation of the canonical model. In contrast, when the players’ flow payoffs are deterministic or their exit payoffs are homogeneous, the game admits equilibria in pure and mixed strategies.
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- 2019
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35. Pre-Opening Price Indications and Market Quality
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Chairat Chuwonganant, Kee H. Chung, and Youngsoo Kim
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Market quality ,Value (economics) ,Economics ,Monetary economics ,Volatility (finance) ,Price discovery ,Stock (geology) ,Market maker ,Market liquidity - Abstract
This paper explores the role of pre-opening price signals in price discovery and liquidity by analyzing the effect of Rule 48 on stock opening delay and various measures of liquidity. NYSE Rule 48 suspends the responsibility of designated market makers for disseminating pre-opening price indications in the event of extreme market-wide volatility. We show that Rule 48 speeds up the opening of stocks at the expense of lower liquidity. Specifically, the absence of pre-opening price indications results in decreases in various measures of liquidity during the first 30-minutes of the trading day that are statistically and economically significant. We interpret this finding as evidence that liquidity suppliers are less willing to provide liquidity in the absence of a reference point or benchmark regarding the value of a stock.
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- 2019
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36. Operational Risk Management: Optimal Inspection Policy
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Youngsoo Kim and Yuqian Xu
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History ,Polymers and Plastics ,Operations research ,Computer science ,business.industry ,media_common.quotation_subject ,Principal (computer security) ,Wage ,Random element ,Conventional wisdom ,Industrial and Manufacturing Engineering ,Operational risk ,Financial regulation ,Business and International Management ,business ,Operational risk management ,Financial services ,media_common - Abstract
Operational risk is one of the major risks in the financial industry; major banks around the world lost nearly $210 billion from operational risk events between 2011 and 2016 (Huber and Funaro 2018) and inspection on operational risk is required by the Basel Committee on Banking Supervision. Motivated by the importance of operational risk and its current industry regulation, we study how a financial firm can optimally design inspection policies to manage operational risk losses. Specifically, we propose a continuous-time principal-agent model framework to examine a financial firm's (principal) optimal inspection policy and their employees' (agent) effort towards lowering the risk event occurrences. We first consider two commonly used inspection policies, namely, random and periodic policies, and characterize the optimal inspection strategy under each policy. We identify conditions for two different modes of inspection (effort inducement and error correction) as well as nuanced interactions among inspection frequency, penalty charged on errors, and wage paid to employees. We then compare the performances of random and periodic policies. We find that, contrary to conventional wisdom, the random policy is not always optimal; it is dominated by the periodic policy if the inspection cost is sufficiently low. Furthermore, we construct a hybrid policy that strictly dominates random policy and weakly dominates periodic policy, which suggests that a proper reduction of the random element in the inspection policy can always improve its performance. Finally, calibrating model parameters using operational risk data from a major bank in China, we numerically show that our key insights about random, periodic, and hybrid policies are robust to various model extensions.
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- 2019
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37. Curdlan activates dendritic cells through dectin-1 and toll-like receptor 4 signaling
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Youngsoo Kim, Jae Hee Lee, Ki Hwan Park, Hyung Sook Kim, Ki Hun Kim, Sang-Bae Han, Ji Sung Kim, Bang Yeon Hwang, Yong Guk Kim, Jin Tae Hong, Jieun Yun, and Hong Kyung Lee
- Subjects
0301 basic medicine ,Skin Neoplasms ,beta-Glucans ,T-Lymphocytes ,T cell ,Immunology ,Melanoma, Experimental ,Syk ,Antineoplastic Agents ,chemical and pharmacologic phenomena ,Curdlan ,Lymphocyte Activation ,Microbiology ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Movement ,medicine ,Animals ,Immunology and Allergy ,Lectins, C-Type ,RNA, Small Interfering ,Mice, Knockout ,Pharmacology ,CD86 ,Mice, Inbred C3H ,Toll-like receptor ,CD40 ,Alcaligenes faecalis ,biology ,Cell Differentiation ,hemic and immune systems ,Dendritic Cells ,Cell biology ,Mice, Inbred C57BL ,Toll-Like Receptor 4 ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,TLR4 ,biology.protein ,Cytokines ,Inflammation Mediators ,CD80 - Abstract
Curdlan, a β-1,3-glucan isolated from Alcaligenes faecalis, is an agonist of dectin-1 in various immune cells, including dendritic cells (DCs). However, whether curdlan also activates DCs through other receptors remains unknown. In this study, we found that curdlan activates DCs through dectin-1 and toll-like receptor 4 (TLR4). Curdlan increased the expression levels of surface molecules (CD40, CD80, CD86, and MHC-I/II), the production of cytokines (IL-12, IL-1β, TNF-α, and IFN-β), migration toward MIP-3β, and allogeneic T cell stimulation activity of DCs. Curdlan increased the phosphorylation of Syk, Raf-1, Akt, MAPKs, IKK, and NF-κB p65 in DCs. However, curdlan only slightly activated DCs transfected with small interfering RNAs against dectin-1 or TLR4 and C3H/HeJ DCs, which have non-functional TLR4, in comparison with control DCs. Curdlan increased antitumor activity of DCs in a syngeneic tumor model. In summary, our data show that curdlan activates DCs through dectin-1 and TLR4 signaling and the combination of curdlan and DCs efficiently inhibit tumor growth in mice.
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- 2016
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38. Cytokine-induced killer cells interact with tumor lysate–pulsed dendritic cells via CCR5 signaling
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Boyeong Kim, Youngsoo Kim, Jong Soon Kang, Ji Sung Kim, Hong Kyung Lee, Sang-Bae Han, Yong Guk Kim, Jin Tae Hong, Eun Jae Park, and Ki Hwan Park
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Cytotoxicity, Immunologic ,Cancer Research ,Time Factors ,Genotype ,Receptors, CCR5 ,viruses ,Melanoma, Experimental ,Cell Communication ,CCR5 receptor antagonist ,Biology ,Transfection ,Time-Lapse Imaging ,CCL5 ,03 medical and health sciences ,chemistry.chemical_compound ,Cytokine-Induced Killer Cells ,0302 clinical medicine ,Cell–cell interaction ,In vivo ,Animals ,Chemokine CCL5 ,Cells, Cultured ,Maraviroc ,Mice, Knockout ,Cytokine-induced killer cell ,virus diseases ,Dendritic Cells ,Coculture Techniques ,In vitro ,Tumor Burden ,Mice, Inbred C57BL ,Chemotaxis, Leukocyte ,Phenotype ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Immunology ,Cancer research ,RNA Interference ,Cell activation ,Signal Transduction ,030215 immunology - Abstract
The antitumor activity of cytokine-induced killer (CIK) cells can be increased by co-culturing them with tumor lysate-pulsed dendritic cells (tDCs); this phenomenon has been studied mainly at the population level. Using time-lapse imaging, we examined how CIK cells gather information from tDCs at the single-cell level. tDCs highly expressed CCL5, which bound CCR5 expressed on CIK cells. tDCs strongly induced migration of Ccr5(+/+) CIK cells, but not that of Ccr5(-/-) CIK cells or Ccr5(+/+) CIK cells treated with the CCR5 antagonist Maraviroc. Individual tDCs contacted Ccr5(+/+) CIK cells more frequently and lengthily than with Ccr5(-/-) CIK cells. Consequently, tDCs increased the antitumor activity of Ccr5(+/+) CIK cells in vitro and in vivo, but did not increase that of Ccr5(-/-) CIK cells. Taken together, our data provide insight into the mechanism of CIK cell activation by tDCs at the single-cell level.
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- 2016
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39. Immunomodulatory Activities of the Benzoxathiole Derivative BOT-4-One Ameliorate Pathogenic Skin Inflammation in Mice
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Yong Nyun Kim, Ae Nim Pae, Byung Hak Kim, Sang Kyu Ye, Youngsoo Kim, Ae Jin Jeong, Yu Chen Li, Kwang-Ho Lee, Sung Ja Rhie, Jung Sook Choi, Myoung Hwan Kim, Hyun Gyu Lee, and Nam-Chul Cho
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0301 basic medicine ,Lipopolysaccharide ,Regulatory T cell ,Inflammation ,Dermatology ,IκB kinase ,Biology ,Lymphocyte Activation ,Sensitivity and Specificity ,Biochemistry ,Dermatitis, Atopic ,Immunomodulation ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Immune system ,T-Lymphocyte Subsets ,RAR-related orphan receptor gamma ,medicine ,Animals ,Molecular Biology ,Cells, Cultured ,Biopsy, Needle ,FOXP3 ,Cell Differentiation ,Cell Biology ,Bridged Bicyclo Compounds, Heterocyclic ,Immunohistochemistry ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,Dermatitis, Allergic Contact ,Immunology ,STAT protein ,medicine.symptom - Abstract
T-cell-mediated immune responses play an important role in body protection. However, aberrantly activated immune responses are responsible for inflammatory and autoimmune diseases. The regulation of pathologic immune responses may be a potential therapeutic strategy for the treatment of these diseases. Despite that multiple pharmacologic properties of benzoxathiole derivatives have been defined, the molecular mechanisms underlying these properties remain to be clarified. Here, we demonstrated the benzoxathiole derivative 2-cyclohexylimino-6-methyl-6,7-dihydro-5H-benzo[1,3]oxathiol-4-one (BOT-4-one) regulated immune responses and ameliorated experimentally induced inflammatory skin diseases both in vitro and in vivo. BOT-4-one inhibited the differentiation of CD4(+) T-cell subsets by regulating the expression and production of T-cell lineage-specific master transcription factors and cytokines and activating the signal transducer and activator of transcription proteins. In addition, BOT-4-one inhibited TCR-mediated Akt and NF-κB signaling. Topical application of BOT-4-one ameliorated experimentally induced inflammatory skin diseases in mice models such as 2,4,6-trinitrochlorobenzene-induced contact and atopic dermatitis and IL-23-induced psoriasis-like skin inflammation. Our study demonstrated that BOT-4-one ameliorates inflammatory skin diseases by suppressing the pathogenic CD4(+) T cell differentiation and overall immune responses.
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- 2016
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40. Imaging the third gasotransmitter hydrogen sulfide using a 99mTc-labeled polyhydroxy weak acid
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Jeong Chan Park, Yong Jin Lee, Youngsoo Kim, and Jae Min Jeong
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Cancer Research ,chemistry.chemical_compound ,chemistry ,Hydrogen sulfide ,Inorganic chemistry ,Molecular Medicine ,Radiology, Nuclear Medicine and imaging - Published
- 2019
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41. Energy-saving decision making framework for HVAC with usage logs
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Ji Young Kim, Seokho Kang, Seung-kyung Lee, Youngsoo Kim, Jooseoung Park, Sungzoon Cho, and Dong Seuk Choi
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Engineering ,Architectural engineering ,business.industry ,Mechanical Engineering ,Building and Construction ,Energy consumption ,Unit (housing) ,Energy conservation ,Air conditioning ,HVAC ,Management system ,Business intelligence ,Electrical and Electronic Engineering ,business ,Energy (signal processing) ,Civil and Structural Engineering - Abstract
Commercial and residential buildings account for 40% of total energy usage in the United Sates. Efforts have been made to better manage energy through the implementation of building energy management systems. In particular, heating, ventilating, and air conditioning consume 50% of energy used in buildings. The system air-conditioner, an individually as well as centrally controlled HVAC system, is widely used across Asia. As energy cost increases, building managers often take building-wide energy saving measures, such as intermittent indoor unit shut-down and setting units to uncomfortable temperatures. In this paper, we argue that a smarter approach is possible. Analyzing a large amount of data collected from indoor units, we see that these units have varying levels of energy consumption and that we can identify those that consume more energy than others, resulting in individual measures for each. We propose a business intelligence framework that allows us to see why certain rooms consume more energy than others through three variables: hours of power-on, hours of thermo-on, and a timeframe of power-on. All variables are visualized, providing building managers with an intuitive understanding of their buildings’ energy consumption. We used real-world data to validate the framework and received positive feedbacks from domain experts.
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- 2015
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42. Targeted glycoengineering extends the protein N-glycosylation pathway in the silkworm silk gland
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Youngsoo Kim, Chu-Wei Kuo, Hideaki Mabashi-Asazuma, Donald L. Jarvis, Cheryl A. Kucharski, Kay-Hooi Khoo, Malcolm J. Fraser, and Bonghee Sohn
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Male ,Glycosylation ,Transgene ,Genetic Vectors ,Silk ,Protein Engineering ,Biochemistry ,Article ,law.invention ,Animals, Genetically Modified ,chemistry.chemical_compound ,Exocrine Glands ,N-linked glycosylation ,Polysaccharides ,law ,Glycosyltransferase ,Animals ,Secretion ,Molecular Biology ,Glycoproteins ,chemistry.chemical_classification ,biology ,fungi ,Glycosyltransferases ,Bombyx ,Molecular biology ,Recombinant Proteins ,Cell biology ,SILK ,chemistry ,Larva ,Insect Science ,Recombinant DNA ,biology.protein ,Female ,Glycoprotein - Abstract
The silkworm silk glands are powerful secretory organs that can produce and secrete proteins at high levels. As such, it has been suggested that the biosynthetic and secretory power of the silk gland can be harnessed to produce and secrete recombinant proteins in tight or loose association with silk fibers. However, the utility of the silkworm platform is constrained by the fact that it has a relatively primitive protein N-glycosylation pathway, which produces relatively simple insect-type, rather than mammalian-type N-glycans. In this study, we demonstrate for the first time that the silk gland protein N-glycosylation pathway can be glycoengineered. We accomplished this by using a dual piggyBac vector encoding two distinct mammalian glycosyltransferases under the transcriptional control of a posterior silk gland (PSG)-specific promoter. Both mammalian transgenes were expressed and each mammalian N-glycan processing activity was induced in transformed silkworm PSGs. In addition, the transgenic animals produced endogenous glycoproteins containing significant proportions of mammalian-type, terminally galactosylated N-glycans, while the parental animals produced none. This demonstration of the ability to glycoengineer the silkworm extends its potential utility as a recombinant protein production platform.
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- 2015
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43. Design, synthesis, and biological evaluation of benzofuran- and 2,3-dihydrobenzofuran-2-carboxylic acid N-(substituted)phenylamide derivatives as anticancer agents and inhibitors of NF-κB
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Youngsoo Kim, Sang-Bae Han, Hyeju Jo, Jungsook Cho, Arepalli Sateesh Kumar, Minho Choi, Joonkwang Lee, Heesoon Lee, Hyun-Jung Park, Jae-Hwan Kwak, Kiho Lee, Jae-Kyung Jung, and Jieun Yun
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Lipopolysaccharides ,Cell Survival ,Stereochemistry ,Carboxylic acid ,Clinical Biochemistry ,Carboxylic Acids ,Sulforhodamine B ,Pharmaceutical Science ,Antineoplastic Agents ,Plasma protein binding ,Biochemistry ,Cell Line ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Drug Discovery ,Animals ,Humans ,Structure–activity relationship ,Benzofuran ,Molecular Biology ,Benzofurans ,chemistry.chemical_classification ,Organic Chemistry ,NF-kappa B ,NF-κB ,Amides ,chemistry ,Cell culture ,Drug Design ,Molecular Medicine ,Drug Screening Assays, Antitumor ,Lead compound ,Protein Binding ,Signal Transduction - Abstract
With the aim of developing novel scaffolds as anticancer agents and inhibitors of NF-κB activity, 60 novel benzofuran- and 2,3-dihydrobenzofuran-2-carboxylic acid N-(substituted)phenylamide derivatives (1a-s, 2a-k, 3a-s, and 4a-k) were designed and synthesized from the reference lead compound KL-1156, which is an inhibitor of NF-κB translocation to the nucleus in LPS-stimulated RAW 264.7 macrophage cells. The novel benzofuran- and 2,3-dihydrobenzofuran-2-carboxamide derivatives exhibited potent cytotoxic activities (measured by the sulforhodamine B assay) at low micromolar concentrations against six human cancer cell lines: ACHN (renal), HCT15 (colon), MM231 (breast), NUGC-3 (gastric), NCI-H23 (lung), and PC-3 (prostate). In addition, these compounds also inhibited LPS-induced NF-κB transcriptional activity. The +M effect and hydrophobic groups on the N-phenyl ring potentiated the anticancer activity and NF-κB inhibitory activity, respectively. However, according to the results of structure-activity relationship studies, only benzofuran-2-carboxylic acid N-(4'-hydroxy)phenylamide (3m) was the lead scaffold with both an outstanding anticancer activity and NF-κB inhibitory activity. This novel lead scaffold may be helpful for investigation of new anticancer agents that act through inactivation of NF-κB.
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- 2015
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44. Saucerneol D inhibits dendritic cell activation by inducing heme oxygenase-1, but not by directly inhibiting toll-like receptor 4 signaling
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Jin Tae Hong, Youngsoo Kim, Bang Yeon Hwang, Ji Sung Kim, Jieun Yun, Hong Kyung Lee, Minji Pyo, Yong Guk Kim, Hwa Sun Ryu, and Sang-Bae Han
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T-Lymphocytes ,T cell ,Anti-Inflammatory Agents ,Lymphocyte Activation ,Plant Roots ,Lignans ,Mice ,Cell Movement ,Saururaceae ,Drug Discovery ,medicine ,Animals ,Pharmacology ,CD86 ,Mice, Inbred BALB C ,Toll-like receptor ,CD40 ,biology ,Dendritic Cells ,Dendritic cell ,IRAK4 ,Cell biology ,Mice, Inbred C57BL ,Toll-Like Receptor 4 ,Heme oxygenase ,medicine.anatomical_structure ,Biochemistry ,biology.protein ,Cytokines ,Female ,Heme Oxygenase-1 ,CD80 ,Signal Transduction - Abstract
Ethnopharmacological relevance Saururus chinensis is a medicinal plant used to treat jaundice, pneumonia, edema, fever, and several inflammatory diseases. Saucerneol D (SD), a lignan constituent of this plant, has antioxidant, anti-asthmatic, and anti-inflammatory activities. SD has been previously reported to inhibit the pro-inflammatory responses of RAW264.7 cells and primary mast cells. In this study, we investigated the effect of SD on the functions of dendritic cells (DCs). Materials and methods SD was isolated from methanol extract of the roots of S. chinensis . Bone marrow-derived DCs were used as target cells. The effects of SD on the following DC functions were examined: surface molecule expression, cytokine expression, migration, allogenic T cell activation, heme oxygenase-1 expression, and Toll-like receptor 4 signaling. Results In lipopolysaccharide (LPS)-treated DCs, SD inhibited the expression of cell surface molecules (MHC I/II, CD40, CD80, and CD86), the production of inflammatory mediators (nitric oxide, IL-12, IL-1β, and TNF-α), and allogenic T cell activation capacity. SD also inhibited DC migration toward MIP-3β by down-regulating CCR7 expression. SD attenuated LPS-induced activation of NF-κB and MAPK signaling in DCs, but did not directly inhibit kinase activities of IRAK1, IRAK4, TAK1, or IKKβ in enzymatic assays. SD did not inhibit LPS binding to myeloid differentiation protein-2, co-receptor of TLR4. SD increased the production of reactive oxygen species, Nrf-2, and heme oxygenase (HO)-1, which degrades the heme to immunosuppressive carbon monoxide and biliverdin, which may underlie the anti-inflammatory effects in SD-treated DCs. Conclusions Taken together, these data suggest that SD suppresses LPS-induced activation of DCs through the induction of HO-1, but not by directly affecting Toll-like receptor 4 signaling.
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- 2015
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45. Exploration of benzamidochromenone derivatives with conformational restrictor as interleukin-5 inhibitors
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Sang-Hun Jung, Pulla Reddy Boggu, Manoj Manickam, Eeda Venkateswararao, and Youngsoo Kim
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Models, Molecular ,Stereochemistry ,Methyl acetate ,Clinical Biochemistry ,Molecular Conformation ,Gene Expression ,Pharmaceutical Science ,Ring (chemistry) ,Biochemistry ,Cell Line ,Inhibitory Concentration 50 ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Drug Discovery ,Side chain ,Animals ,Humans ,Immunologic Factors ,Moiety ,Benzopyrans ,Hydroxymethyl ,Anti-Asthmatic Agents ,Lymphocytes ,Molecular Biology ,Conformational isomerism ,IC50 ,Cell Proliferation ,Hydrogen bond ,Organic Chemistry ,Hydrogen Bonding ,chemistry ,Molecular Medicine ,Interleukin-5 ,Hydrophobic and Hydrophilic Interactions - Abstract
Novel amidochromen-4-one analogs 8a-k and 9a-f were prepared and studied for their IL-5 inhibitory activity. Among the synthesized compounds, (6-benzamido-2-cyclohexyl-4-oxo-4H-chromen-3-yl)methyl acetate (8a, 95% inhibition at 30 μM, IC50=6.1 μM) exhibited potent IL-5 inhibitory activity. The conformational restrictor at position 2 like bulky cyclohexyl group is favorable for the formation of effective conformer of side chain small ester like acetoxymethyl at position 3 of these chromenone analogs 8. In addition the hydrophobic planarity of benzamido group at position 6 should be important for the potent IL-5 inhibitory activity. Since replacing acetoxymethyl moiety with hydroxymethyl group at position 3 of chromenone decreases the activity, which indicates that the location of hydrogen bonding group should be near 4 atom distances away from chromenone ring is more optimum for the activity. Therefore, these benzamidochromen-4-one analogs 8 are novel scaffold for finding potent interleukin-5 inhibitors.
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- 2015
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46. Etiology and prognosis of non-convulsive status epilepticus
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Sang Kun Lee, Yunsook Jhang, Bong Su Kang, Kon Chu, Youngsoo Kim, Keun-Hwa Jung, Jangsup Moon, Jung-Won Shin, Kyung-Il Park, Soon-Tae Lee, and Hye Jin Moon
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Adult ,Male ,medicine.medical_specialty ,Pediatrics ,Adolescent ,Neuroimaging ,Status epilepticus ,Infections ,Young Adult ,Epilepsy ,Status Epilepticus ,Acute onset ,Physiology (medical) ,Republic of Korea ,medicine ,Humans ,Coma ,Aged ,Retrospective Studies ,Aged, 80 and over ,Brain Diseases, Metabolic ,Convulsive status epilepticus ,business.industry ,Persistent Vegetative State ,Medical record ,Brain ,Electroencephalography ,General Medicine ,Middle Aged ,Prognosis ,University hospital ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Stroke ,Neurology ,Etiology ,Consciousness Disorders ,Anticonvulsants ,Female ,Neurology (clinical) ,medicine.symptom ,business ,Neurological problems - Abstract
Although non-convulsive status epilepticus (NCSE) is an important type of epilepsy, it is not often recognized. In order to analyze the clinical characteristics and outcome in patients with NCSE, we examined the medical records of patients with NCSE admitted to the Seoul National University Hospital between June 2005 and October 2008. The clinical details and electroencephalography records of 34 adult NCSE patients (aged over 16 years) were collected. Their mean age was 47 years (standard deviation 20 years, range, 16–87 years), and 20 were female. Twenty-seven patients (79.4%) showed decreased awareness with acute onset, and seven (20.6%) were obtunded or comatose. Ten patients (29.4%) had a history of epilepsy, and four (11.8%) had a history of stroke. NCSE was etiologically attributed to acute medical or neurological problems in 25 patients (73.5%), was cryptogenic in three (8.8%), and was secondary to underlying epilepsy in six (17.7%). Acute symptomatic etiology was associated with poor recovery (p = 0.048), with all unresponsive patients in this acute symptomatic group. Eight (23.5%) of the 34 NCSE patients did not recover or died, whereas nine (26.5%) recovered. Our study shows that the presence of acute symptoms or central nervous system infection is associated with poor outcome, suggesting that a high level of vigilance is required to identify and prevent complications.
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- 2014
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47. Tussilagone inhibits dendritic cell functions via induction of heme oxygenase-1
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Sang-Bae Han, Jong Soon Kang, Ji Sung Kim, Hong Kyung Lee, Hwa Sun Ryu, Youngsoo Kim, Jieun Yun, Bang Yeon Hwang, Yunsoo Park, and Jin Tae Hong
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T-Lymphocytes ,medicine.medical_treatment ,Immunology ,IκB kinase ,Biology ,Nitric Oxide ,chemistry.chemical_compound ,medicine ,Animals ,Immunology and Allergy ,Heme ,Pharmacology ,Mice, Inbred BALB C ,Kinase ,Membrane Proteins ,NF-κB ,Dendritic Cells ,Dendritic cell ,Cell biology ,Mice, Inbred C57BL ,Toll-Like Receptor 4 ,Heme oxygenase ,Cytokine ,chemistry ,Biochemistry ,Cytokines ,Female ,Lymphocyte Culture Test, Mixed ,Reactive Oxygen Species ,Cell activation ,Protein Kinases ,Sesquiterpenes ,Heme Oxygenase-1 ,Spleen - Abstract
Sesquiterpenoid tussilagone (TUS) has a variety of pharmacological activities, such as anti-oxidant, anti-cancer, and anti-inflammatory activities. In this study, we investigated the effects of TUS on dendritic cell (DC) functions and the underlying mechanisms. TUS inhibited lipopolysaccharide (LPS)-induced activation of DCs, as shown by decrease in surface molecule expression, cytokine production, cell migration, and allo-T cell activation. In addition, TUS inhibited LPS-induced activation of NF-κB, MAPKs, and IRF-3 signalings in DCs, although it did not directly affect kinase activities of IRAK1/4, TAK1, and IKK, which suggests that TUS might indirectly inhibit TLR signaling in DCs. As a critical mechanism, we showed that TUS activated heme oxygenase-1 (HO-1), which degrades heme to immunosuppressive products, such as carbon monoxide and bilirubin. HO-1 inhibitor reversed the inhibitory activity of TUS in DCs. In conclusion, this study suggests that TUS inhibits DC function through the induction of HO-1.
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- 2014
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48. Anti-proliferative effect of chalcone derivatives through inactivation of NF-κB in human cancer cells
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Jieun Yun, Vinay K. Sharma, Youngsoo Kim, Sang-Hun Jung, and Eeda Venkateswararao
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Chalcone ,Dose-Response Relationship, Drug ,Molecular Structure ,Organic Chemistry ,Clinical Biochemistry ,NF-kappa B ,Pharmaceutical Science ,NF-κB ,Anti proliferative ,Biochemistry ,Structure-Activity Relationship ,chemistry.chemical_compound ,chemistry ,Cell culture ,Cell Line, Tumor ,Drug Discovery ,Humans ,Molecular Medicine ,Drug Screening Assays, Antitumor ,Molecular Biology ,Human cancer ,Cell Proliferation - Abstract
To investigate the anti-proliferative effect of NF-κB inhibitor, a series of analogs of ( E )-1-(2-hydroxy-6-(isopentyloxy)phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one ( 5a ) were prepared and evaluated for their NF-κB inhibition and anti-proliferative activity against various human cancer cell lines. Compounds ( E )-1-(2-(3,3-dimethylbutoxy)-6-hydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one ( 5e ) and ( E )-4-(3-(2-(3,3-dimethylbutoxy)-6-hydroxyphenyl)-3-oxoprop-1-enyl)benzenesulfonamide ( 5p ) showed good NF-κB inhibition as well as potent anti-proliferative activity. SAR studies showed that all the compounds with potent or moderate NF-κB inhibition displayed good anti-proliferative activity. All the analogs ( 5b – r ) maintained a good correlation between their NF-κB inhibition and anti-proliferative activity though the extent is not directly proportional to each other.
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- 2014
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49. Clinical manifestations and outcomes of the treatment of patients with GABAB encephalitis
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Jung Won Shin, Keon-Joo Lee, Jung Ick Byun, Jangsup Moon, Sang Kun Lee, Tae Joon Kim, Kon Chu, Youngsoo Kim, Kyung-Il Park, Soon-Tae Lee, Kunhwa Jung, Jung Ah Lim, and Yong Won Shin
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Male ,Oncology ,medicine.medical_specialty ,Pathology ,Lung Neoplasms ,Immunology ,Antineoplastic Agents ,GABAB receptor ,Autoantigens ,Autoimmune Diseases of the Nervous System ,Carcinoma, Non-Small-Cell Lung ,Limbic Encephalitis ,Internal medicine ,Brain positron emission tomography ,Humans ,Immunology and Allergy ,Medicine ,Good outcome ,Lung cancer ,Aged ,Autoantibodies ,biology ,business.industry ,Middle Aged ,Immune modulation ,medicine.disease ,Treatment Outcome ,Receptors, GABA-B ,Neurology ,biology.protein ,Female ,Neurology (clinical) ,Antibody ,business ,Encephalitis - Abstract
Encephalitis associated with anti-γ-aminobutyric acid-B (GABAB) receptor antibodies has been identified recently. However, only a few cases have been reported to date and its clinical manifestations and prognosis have not been investigated systematically. We identified five cases of GABAB encephalitis in Korea. Here we present the clinical features, treatment responses, and brain positron emission tomography findings of the cases. The patients had a clinical triad of memory changes, seizure, and association with small-cell lung cancer. Early diagnosis and comprehensive immune modulation may provide a good outcome.
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- 2014
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50. Frequency of and risk factors for oxcarbazepine-induced severe and symptomatic hyponatremia
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Dong-Wook Kim, Keun-Hwa Jung, Jung Sook Yeom, Bong Su Kang, Youngsoo Kim, Jung-Ick Byun, Kon Chu, Soon-Tae Lee, and Sang Kun Lee
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Adult ,Male ,medicine.medical_specialty ,Clinical Neurology ,Oxcarbazepine ,Asymptomatic ,Indole Alkaloids ,Epilepsy ,Young Adult ,Risk Factors ,Internal medicine ,medicine ,Humans ,Adverse effect ,Aged ,Retrospective Studies ,Analysis of Variance ,business.industry ,Sodium ,nutritional and metabolic diseases ,Retrospective cohort study ,General Medicine ,Middle Aged ,medicine.disease ,Discontinuation ,Neurology ,Anesthesia ,Concomitant ,Anticonvulsants ,Female ,Neurology (clinical) ,medicine.symptom ,Hyponatremia ,business ,Antiepileptic drug ,medicine.drug - Abstract
PurposeHyponatremia is one of the most common adverse effects in patients treated with oxcarbazepine (OXC). Most patients with OXC-induced hyponatremia are asymptomatic, so the presence of severe or symptomatic hyponatremia, which requires electrolyte correction or discontinuation of OXC therapy, has more important clinically implications. However, data for OXC-induced severe and symptomatic hyponatremia are limited.MethodsWe reviewed medical records of all patients with epilepsy who were treated with OXC at the Seoul National University Hospital. We analyzed serum sodium level results and attempted to identify correlations between various factors and the frequency of severe and symptomatic OXC-induced hyponatremia.ResultsData from a total 1009 patient were examined. The frequency of severe and symptomatic hyponatremia was 11.1% and 6.8%, respectively. Multivariate analysis revealed that age (P=0.014, OR 1.014), antiepileptic drug (AED) polytherapy (P=0.040, OR 1.540), and the concomitant use of diuretics (P
- Published
- 2014
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