20 results on '"Jun-Hee Park"'
Search Results
2. The downregulation of IGFBP3 by TGF-β signaling in oral cancer contributes to the osteoclast differentiation
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Jun-Hee Park, Won Yoon Chung, and Min Ju Jung
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Male ,0301 basic medicine ,Osteolysis ,medicine.medical_treatment ,Biophysics ,Down-Regulation ,Osteoclasts ,Biochemistry ,Small hairpin RNA ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Osteogenesis ,Transforming Growth Factor beta ,Osteoclast ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Insulin-Like Growth Factor I ,Molecular Biology ,Mice, Inbred ICR ,Squamous Cell Carcinoma of Head and Neck ,Chemistry ,Macrophages ,Growth factor ,RANK Ligand ,Osteoprotegerin ,Receptor, Transforming Growth Factor-beta Type II ,Cancer ,Cell Differentiation ,Cell Biology ,medicine.disease ,Insulin-Like Growth Factor Binding Protein 3 ,030104 developmental biology ,Cytokine ,medicine.anatomical_structure ,Matrix Metalloproteinase 9 ,Gene Knockdown Techniques ,030220 oncology & carcinogenesis ,Cancer cell ,Cancer research ,Mouth Neoplasms ,Bone marrow ,Signal Transduction - Abstract
Oral squamous cell carcinoma (OSCC) frequently invades nearby bone and bone involvement determines the prognosis of patients. Growth factors, stored in the bone matrix and released during bone destruction, are known as key components in the bone-tumor interaction. However, the coordination of growth factor signals and the precise mechanism of bone destruction in oral cancer are still unclear. In the study, we investigated the differential cytokine expression profile of oral cancer cells by TGF-β treatment and the function of altered expression of cytokines on the osteoclast differentiation. We established TGFBR2-knockdown cells using small hairpin RNA. TGF-β was treated to both TGFBR2 expressing and knockdown cells and the culture supernatants were analyzed using a cytokine array kit. We found that the TGF-β inhibited IGFBP3 level and enhanced MMP9 level. We confirmed this regulation of IGFBP3 and MMP9 by TGF-β using ELISA and zymography, respectively. IGFBP3 is known as to modulate the bioavailability of IGF1, which is abundant in the bone microenvironment and regulates osteoclast differentiation. Therefore, we further analyzed the function of IGFBP3 on osteoclastogenesis. Although IGFBP3 increased the viability of murine bone marrow macrophages, the osteoclast differentiation of these cells was blocked by IGFBP3 in a dose-dependent manner. These results revealed a novel pathway for the regulation of osteoclastogenesis by oral cancer cells, which may be a new therapeutic target for osteolysis induced by oral cancer infiltrating into the bone.
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- 2021
3. Material enhancements of newly developed stiff type polyurea for retrofitting of concrete structures
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Tae-Hee Lee, Jun-Hee Park, Dal-Hun Yang, Jang-Ho Jay Kim, and Norhazilan Bin Md. Noor
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Materials Science (miscellaneous) - Published
- 2022
4. Hypersensitive electrochemical immunoassays based on highly N-doped silicon carbide (SiC) electrode
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Ga Yeon Lee, Seong Min Jeong, Jun Hee Park, Zhiquan Song, Jae Chul Pyun, and Min Jung Kang
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Carbon Compounds, Inorganic ,Analytical chemistry ,Biosensing Techniques ,02 engineering and technology ,Electrochemistry ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,law.invention ,Luminol ,chemistry.chemical_compound ,stomatognathic system ,law ,Silicon carbide ,medicine ,Humans ,Environmental Chemistry ,Electrodes ,Spectroscopy ,Chemiluminescence ,Immunoassay ,Hepatitis B Surface Antigens ,medicine.diagnostic_test ,Benzidines ,Silicon Compounds ,010401 analytical chemistry ,HIV ,Electrochemical Techniques ,Chronoamperometry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Electrode ,0210 nano-technology ,Electrochemical window - Abstract
Highly N-doped SiC was presented as an optimal electrode for electrochemical immunoassays with a far higher sensitivity than chemiluminescence detection. As the first step, the electrochemical properties of highly N-doped SiC, such as the double-layer capacitance (Cdl), rate constant for electron transfer (kapp) and ideal polarizable potential range (electrochemical window) were analyzed and compared with those of Au, Pt, and graphite electrodes. The highly N-doped SiC electrode was used for the quantification of oxidized 3,3′,5,5′-tetramethylbenzidine (TMB) which was widely used as chromogenic substrate for commercialized immunoassay kits. In order to enhance the sensitivity for the quantification of the oxidized TMB the chronoamperometry was applied to avoid the background current of i-V measurement. Finally, the chronoamperometry based on the highly N-doped SiC electrode was applied to commercial immunoassay kits for the medical diagnosis of the human immunodeficiency virus (HIV) and the human hepatitis B surface antigen (hHBsAg). The chronoamperometric measurement based on the highly N-doped SiC electrode was proved to detect at far lower limits in comparison with the conventional optical density measurement as well as the chemiluminescence assay based on luminol as a chemiluminescent probe.
- Published
- 2019
5. Capacitive biosensor based on vertically paired electrodes for the detection of SARS-CoV-2
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Jun-Hee Park, Ga-Yeon Lee, Zhiquan Song, Ji-Hong Bong, Young Wook Chang, Sungbo Cho, Min-Jung Kang, and Jae-Chul Pyun
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Immunoassay ,Capacitive biosensor ,SARS-CoV-2 ,viruses ,Biomedical Engineering ,Biophysics ,COVID-19 ,Biosensing Techniques ,General Medicine ,Nucleoprotein (NP) ,Sensitivity and Specificity ,Article ,Electrochemistry ,Humans ,PEDOT:PSS ,Computer Simulation ,Electrodes ,Vertically paired electrode ,Biotechnology - Abstract
Vertically paired electrodes (VPEs) with multiple electrode pairs were developed for the enhancement of capacitive measurements by optimizing the electrode gap and number of electrode pairs. The electrode was fabricated using a conductive polymer layer of PEDOT:PSS instead of Ag and Pt metal electrodes to increase the VPE fabrication yield because the PEDOT:PSS layer could be effectively etched using a reactive dry etching process. In this study, sensitivity enhancement was realized by decreasing the electrode gap and increasing the number of VPE electrode pairs. Such an increase in sensitivity according to the electrode gap and the number of electrode pairs was estimated using a model analyte for an immunoassay. Additionally, a computer simulation was performed using VPEs with different electrode gaps and numbers of VPE electrode pairs. Finally, VPEs with multiple electrode pairs were applied for SARS-CoV-2 nucleoprotein (NP) detection. The capacitive biosensor based on the VPE with immobilized anti-SARS-CoV-2 NP was applied for the specific detection of SARS-CoV-2 in viral cultures. Using viral cultures of SARS-CoV-2, SARS-CoV, MERS-CoV, and CoV-strain 229E, the limit of detection (LOD) was estimated to satisfy the cutoff value (dilution factor of 1/800) for the medical diagnosis of COVID-19, and the assay results from the capacitive biosensor were compared with commercial rapid kit based on a lateral flow immunoassay.
- Published
- 2022
6. Capacitive biosensor based on vertically paired electrode with controlled parasitic capacitance
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Jae Chul Pyun, Min Jung Kang, Jun Hee Park, Sungbo Cho, Young Wook Chang, and Ga Yeon Lee
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Materials science ,Capacitive measurement ,02 engineering and technology ,01 natural sciences ,chemistry.chemical_compound ,Parylene ,Parasitic capacitance ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,Electrical impedance ,business.industry ,010401 analytical chemistry ,Metals and Alloys ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Electrode ,Optoelectronics ,Capacitive biosensor ,Nanometre ,0210 nano-technology ,business ,Sensitivity (electronics) - Abstract
A capacitive biosensor based on vertically paired electrodes with controlled parasitic capacitance is presented to improve the sensitivity of capacitive measurement. The vertically paired electrodes were fabricated with a parylene film as a dielectric layer, with the distance between the electrodes less than hundreds of nanometer. The problem of parasitic capacitance owing to the electrode configuration was analyzed according to the superposed area of the electrode. In this work, two kinds of vertically paired electrodes were fabricated to control the parasitic capacitance—square-type and circular-type electrodes with different superimposed areas of 21.8 (100%) and 9.3 (42%) mm2 and the same electrode area of 9.4 × 10−5 mm2, respectively. The effect of superimposed area of the vertically paired electrodes on capacitive measurement was analyzed using the electrodes. The sensitivity of capacitive measurement was observed to increase with a decrease in superimposed electrode area and frequency. Further, the effect of parasitic capacitance was estimated by computer simulation of the sensitivity of impedance and capacitive measurement when 10% change in RS or CS occurred. The results showed that adsorption of proteins could be sensitively measured when the parasitic capacitance decreased. Finally, the effect of superimposed area of the vertically paired electrodes was measured from the interaction between antigens (human serum albumin, HSA) and immobilized antibodies (anti-HSA antibodies).
- Published
- 2018
7. Scalable long-term extraction of photosynthetic electrons by simple sandwiching of nanoelectrode array with densely-packed algal cell film
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Yong Jae Kim, Jae Chul Pyun, Seon Il Kim, Jae Hyoung Yun, Jun Hee Park, Hyeonaug Hong, and WonHyoung Ryu
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Materials science ,Biomedical Engineering ,Biophysics ,Oxide ,Electrons ,Biosensing Techniques ,02 engineering and technology ,010402 general chemistry ,Photosynthesis ,01 natural sciences ,chemistry.chemical_compound ,Chlorophyta ,Etching (microfabrication) ,Monolayer ,Electrochemistry ,Electrodes ,Photosystem ,fungi ,food and beverages ,General Medicine ,021001 nanoscience & nanotechnology ,Plant cell ,Isotropic etching ,0104 chemical sciences ,Chemical engineering ,chemistry ,Thylakoid ,0210 nano-technology ,Biotechnology - Abstract
Direct extraction of photosynthetic electrons from the whole photosynthetic cells such as plant cells or algal cells can be highly efficient and sustainable compared to other approaches based on isolated photosynthetic apparatus such as photosystems I, II, and thylakoid membranes. However, insertion of nanoelectrodes (NEs) into individual cells are time-consuming and unsuitable for scale-up processes. We propose simple and efficient insertion of massively-populated NEs into cell films in which algal cells are densely packed in a monolayer. After stacking the cell film over an NE array, gentle pressing of the stack allows a large number of NEs to be inserted into the cells in the cell film. The NE array was fabricated by metal-assisted chemical etching (MAC-etching) followed by additional steps of wet oxidation and oxide etching. The cell film was prepared by mixing highly concentrated algal cells with alginate hydrogel. Photosynthetic currents of up to 106 nA/cm2 was achieved without aid of mediators, and the photosynthetic function was maintained for 6 days after NE array insertion into algal cells.
- Published
- 2018
8. Proteome Expression in Human Periodontal Ligament after Delayed Hypothermic Preservation
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Sin Yeon Cho, Won Yoon Chung, Jun-Hee Park, Seung-Jong Lee, Il-Young Jung, Seong-Ho Choi, Euiseong Kim, and Kwang Kyun Park
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Materials science ,Proteome ,Periodontal Ligament ,medicine.medical_treatment ,Vimentin ,Proteomics ,Cryopreservation ,Tooth Replantation ,Andrology ,Extracellular matrix ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Periodontal fiber ,Electrophoresis, Gel, Two-Dimensional ,General Dentistry ,Tissue Survival ,biology ,030206 dentistry ,030104 developmental biology ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Replantation ,biology.protein ,Collagen - Abstract
Introduction Previous occasional successes after delayed replantation suggest that the presence of viable cells may not be the only factor for successful periodontal regeneration in delayed replantation. Various other factors such as proteins or the extracellular matrix (ECM) may play a role in this process. The purpose of this study was to characterize changes in the proteome components of periodontal ligament (PDL) tissue after hypothermic preservation of the tooth. Methods Extracted teeth were divided into 4 groups: immediate sampling, sampling after 1 week of preservation at 4°C, sampling after 2 weeks of preservation at 4°C, and sampling after 1 week of dry storage at room temperature as a negative control. PDL tissues were collected from the root and stored immediately in liquid nitrogen. The tissues were subjected to 2-dimensional gel electrophoresis, and spot selection was executed. Selected spots that maintained the protein volume were then processed with matrix-assisted laser desorption and ionization time-of-flight mass spectrometry to identify the nature of the proteins. Results Thirty-five selected spots were analyzed. Sixteen spots were identified as vimentin, and 3 spots were type VI collagen. The size of the 16 vimentin spots decreased gradually with increasing storage time, from 0 to 2 weeks, and decreased rapidly after dry storage. However, only the dry storage group differed significantly from the immediately sampled group. Conclusions Vimentin was the most prominent protein followed by type VI collagen in volumetrically maintained protein spots. Although these proteins are known to be closely related with ECM integrity, the role of these proteins in delayed replantation is beyond the scope of this study. Further studies are needed to elucidate the possible role of these proteins for periodontal healing of delayed replantation.
- Published
- 2017
9. Plasma deposition of parylene-C film
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Moo Hwan Kim, Jae Chul Pyun, Ga Yeon Lee, Zhiquan Song, Jun Hee Park, Min Jung Kang, Ju Hee Im, and Hyuk Wan Ko
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Materials science ,Analytical chemistry ,02 engineering and technology ,Plasma ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Evaporation (deposition) ,0104 chemical sciences ,Contact angle ,Crystallinity ,Mechanics of Materials ,Materials Chemistry ,Surface roughness ,Deposition (phase transition) ,General Materials Science ,0210 nano-technology ,Absorption (electromagnetic radiation) ,Visible spectrum - Abstract
A new method that uses plasma energy for the deposition of parylene-C films is presented. The equipment and instrumentation for the plasma deposition of parylene-C films were developed and constructed by combining evaporation and plasma-generating units. The plasma deposition of parylene-C films consists of three steps: evaporation, decomposition of the parylene-C dimers using plasma, and deposition of the film. The entire deposition process from evaporation to deposition was designed to be completed within 20 min for a parylene-C film with a thickness of less than 200 nm. The thickness of the parylene-C film was controlled in the range of 100–200 nm by adjusting the amount of parylene-C dimer as well as the plasma energy. The parylene-C films prepared by plasma deposition were characterized and compared with those obtained using the conventional pyrolysis method. The comparison included the chemical properties (chemical functional groups, atomic compositions) and their physical properties (density, crystallinity, absorption in the visible wavelength range, surface roughness and contact angle).
- Published
- 2021
10. Role of autophagy in cisplatin-induced ototoxicity
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Nam Yong Do, Cha Kyung Youn, Sung Il Cho, Jun Kim, and Jun Hee Park
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Programmed cell death ,Cell Survival ,Blotting, Western ,Fluorescent Antibody Technique ,Antineoplastic Agents ,Apoptosis ,Cell Line ,Phosphatidylinositol 3-Kinases ,Downregulation and upregulation ,Ototoxicity ,Autophagy ,Humans ,Medicine ,Viability assay ,Hearing Loss ,PI3K/AKT/mTOR pathway ,Cisplatin ,business.industry ,TOR Serine-Threonine Kinases ,General Medicine ,Flow Cytometry ,medicine.disease ,Cell biology ,Otorhinolaryngology ,Pediatrics, Perinatology and Child Health ,business ,Microtubule-Associated Proteins ,medicine.drug - Abstract
Objective Hearing loss is a major side effect of cisplatin chemotherapy. Although cell death in cisplatin-induced ototoxicity is primarily caused by apoptosis, the exact mechanism behind the ototoxic effects of cisplatin is not fully understood. Autophagy is generally known as a pro-survival mechanism that protects cells under starvation or stress conditions. However, recent research has reported that autophagy plays a functional role in cell death also. This study aimed to investigate the role of autophagy in cisplatin-induced ototoxicity in an auditory cell line. Methods Cultured HEI-OC1 cells were exposed to 30 μM cisplatin for 48 h, and cell viability was tested using MTT assays. To evaluate whether autophagy serves to cell death after cisplatin exposure, western blotting and immunofluorescence staining for LC3-II were performed. Markers of two autophagy-related pathways, mTOR and class III PI3K, were also investigated. Results The formation of the autophagic protein LC3-II in response to 30 μM cisplatin increased with time. The early upregulation of autophagy exerted cytoprotective activity via the class III PI3K pathway. But later increase in autophagy induced cell death by suppressing the mTOR pathway. Conclusion Our results prove that autophagy could induce cell death during cisplatin-induced ototoxicity, and modulating the autophagic pathway might be another strategy against cisplatin-induced ototoxicity.
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- 2015
11. ROS-mediated bidirectional regulation of miRNA results in distinct pathologic heart conditions
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Seahyoung Lee, Chang Yeon Lee, Se-Yeon Lee, Jiyun Lee, Min-Ji Cha, Eunhyun Choi, Ina Yun, Ki-Chul Hwang, Hyang-Hee Seo, Onju Ham, Jun-Hee Park, Sun M. Han, and Soyeon Lim
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Biophysics ,Ischemia ,Apoptosis ,Cardiomegaly ,Biology ,Biochemistry ,Rats, Sprague-Dawley ,microRNA ,medicine ,Animals ,Molecular Biology ,Pathological ,Cells, Cultured ,Heart Failure ,Regulation of gene expression ,Myocardium ,Nuclear Proteins ,Cell Biology ,medicine.disease ,Phenotype ,Rats ,Cell biology ,MicroRNAs ,Gene Expression Regulation ,Myocardin ,Heart failure ,Immunology ,Trans-Activators ,cardiovascular system ,Reactive Oxygen Species - Abstract
Under distinct pathological heart conditions, the expression of a single miRNA can display completely opposite patterns. However, the mechanism underlying the bidirectional regulation of a single miRNA and the clinical implications of this regulation remain largely unknown. To address this issue, we examined the regulation of miR-1, one of the most abundant miRNAs in the heart, during cardiac hypertrophy and ischemia/reperfusion (I/R). Our data indicated that different magnitudes and chronicities of ROS levels in cardiomyocytes resulted in differential expression of miR-1, subsequently altering the expression of myocardin. In animal models, the administration of a miR-1 mimic attenuated cardiac hypertrophy by suppressing the transverse aortic constriction-induced increase in myocardin expression, whereas the administration of anti-miR-1 ameliorated I/R-induced cardiac apoptosis and deterioration of heart function. Our findings indicated that a pathologic stimulus such as ROS can bidirectionally alter the expression of miRNA to contribute to the development of pathological conditions exhibiting distinct phenotypes and that the meticulous adjustment of the pathological miRNA levels is required to improve clinical outcomes.
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- 2015
12. PLCδ1 Protein Rescues Ischemia-reperfused Heart by the Regulation of Calcium Homeostasis
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Se-Yeon Lee, Ki-Chul Hwang, Woochul Chang, Onju Ham, Jun-Hee Park, Byeong-Wook Song, Yangsoo Jang, Soyeon Lim, Min Ji Cha, Chang Youn Lee, and Sang Kyou Lee
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medicine.medical_specialty ,Recombinant Fusion Proteins ,Ischemia ,Apoptosis ,Myocardial Reperfusion Injury ,Biology ,Mitochondrial Membrane Transport Proteins ,Injections ,Rats, Sprague-Dawley ,Mitochondrial membrane transport protein ,Internal medicine ,Drug Discovery ,medicine ,Genetics ,Myocyte ,Animals ,Myocytes, Cardiac ,Molecular Biology ,Calcium metabolism ,chemistry.chemical_classification ,Membrane Potential, Mitochondrial ,Polycomb Repressive Complex 1 ,Pharmacology ,Reactive oxygen species ,Phospholipase C ,Mitochondrial Permeability Transition Pore ,Phospholipase C gamma ,medicine.disease ,Cell Hypoxia ,Rats ,Endocrinology ,Mitochondrial permeability transition pore ,chemistry ,Animals, Newborn ,biology.protein ,Molecular Medicine ,Calcium ,Original Article ,Reactive Oxygen Species ,Homeostasis - Abstract
Myocardial Ca(2+) overload induced by ischemia/reperfusion (I/R) is a major element of myocardial dysfunction in heart failure. Phospholipase C (PLC) plays important roles in the regulation of the phosphoinositol pathway and Ca(2+) homeostasis in various types of cells. Here, we investigated the protective role of PLCδ1 against myocardial I/R injury through the regulation of Ca(2+) homeostasis. To investigate its role, PLCδ1 was fused to Hph1, a cell-permeable protein transduction domain (PTD), and treated into rat neonatal cardiomyocytes and rat hearts under respective hypoxia-reoxygenation (H/R) and ischemia-reperfusion conditions. Treatment with Hph1-PLCδ1 significantly inhibited intracellular Ca(2+) overload, reactive oxygen species generation, mitochondrial permeability transition pore opening, and mitochondrial membrane potential elevation in H/R neonatal cardiomyocytes, resulting in the inhibition of apoptosis. Intravenous injections of Hph1-PLCδ1 in rats with I/R-injured myocardium caused significant reductions in infarct size and apoptosis and also improved systolic and diastolic cardiac functioning. Furthermore, a small ions profile obtained using time-of-flight secondary ion mass spectrometry showed that treatment with Hph1-PLCδ1 leads to significant recovery of calcium-related ions toward normal levels in I/R-injured myocardium. These results suggest that Hph1-PLCδ1 may manifest as a promising cardioprotective drug due to its inhibition of the mitochondrial apoptotic pathway in cells suffering from I/R injury.
- Published
- 2014
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13. Demonstration of Q-factor enhancement in a mode splitting-based microdisk-coupled asymmetric Mach–Zehnder interferometer
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Eudum Kim, Tae-Kyeong Lee, Dohyun Kim, Jun-Hee Park, Su-Jin Jeon, Young-Wan Choi, Hong-Seung Kim, Tae-Ryong Kim, and Sun-Ho Kim
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Physics ,Waveguide (electromagnetism) ,Extinction ratio ,business.industry ,Resonance ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Mach–Zehnder interferometer ,01 natural sciences ,Signal ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,010309 optics ,Interferometry ,Planar ,Q factor ,0103 physical sciences ,Optoelectronics ,Electrical and Electronic Engineering ,0210 nano-technology ,business - Abstract
We demonstrate significant enhancement of an effective Q-factor in a silica planar waveguide-based asymmetric Mach–Zehnder interferometer (AMZI) coupled with a microdisk. To enhance the Q-factor, which is required to more effectively measure the signal changes occurring during biochemical events, the structure utilizes resonance mode splitting. This phenomenon is observed through power cancellation at the same amplitude and a 180° phase difference of each path in the AMZI. In this study, we experimentally showed the effective Q-factor enhancement by comparing resonance characteristics of a fabricated microdisk, AMZI, and the proposed structure at equal fabrication conditions. We measured an effective Q-factor of 9.15 × 104 with a 22 dB extinction ratio.
- Published
- 2019
14. A colorimetric sandwich-type assay for sensitive thrombin detection based on enzyme-linked aptamer assay
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Jun Hee Park, Gwan-Ho Lee, Eun Jeong Lee, Sungmuk Kang, Yea Seul Cho, and Sang Soo Hah
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chemistry.chemical_classification ,Analyte ,Chromatography ,biology ,Aptamer ,Thrombin ,Biophysics ,Enzyme-Linked Immunosorbent Assay ,Cell Biology ,Aptamers, Nucleotide ,Biochemistry ,Horseradish peroxidase ,Molecular biology ,Sandwich type ,Enzyme ,chemistry ,biology.protein ,medicine ,Animals ,Cattle ,Colorimetry ,Molecular Biology ,Signal amplification ,medicine.drug - Abstract
A colorimetric sandwich-type assay based on enzyme-linked aptamer assay has been developed for the fast and sensitive detection of as low as 25 fM of thrombin with high linearity. Aptamer-immobilized glass was used to capture the target analyte, whereas a second aptamer, functionalized with horseradish peroxidase (HRP), was employed for the conventional 3,5,3′,5′-tetramethylbenzidine (TMB)-based colorimetric detection. Without the troublesome antibody requirement of the conventional enzyme-linked immunosorbent assay (ELISA), as low as 25 fM of thrombin could be rapidly and reproducibly detected. This assay has superior, or at least equal, recovery and accuracy to that of conventional antibody-based ELISA.
- Published
- 2014
15. MicroRNA-145 suppresses ROS-induced Ca2+ overload of cardiomyocytes by targeting CaMKIIδ
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Jiyun Lee, Chang Yeon Lee, Se-Yeon Lee, Eunhyun Choi, Jin-Kyung Jang, Onju Ham, Min-Ji Cha, Hyun-Taek Shin, Eunmi Choi, Jun-Hee Park, Byeong-Wook Song, Woo-min Jeon, Ki-Chul Hwang, Hye Jin Hwang, and Hyang-Hee Seo
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Calmodulin ,Biophysics ,chemistry.chemical_element ,Calcium ,Biochemistry ,Rats, Sprague-Dawley ,Ca2+/calmodulin-dependent protein kinase ,microRNA ,Animals ,Myocytes, Cardiac ,Luciferase ,Molecular Biology ,Cells, Cultured ,Regulation of gene expression ,biology ,Hydrogen Peroxide ,Cell Biology ,Rats ,Cell biology ,MicroRNAs ,Animals, Newborn ,chemistry ,Apoptosis ,biology.protein ,Signal transduction ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 ,Reactive Oxygen Species - Abstract
Highlights: •CaMKIIδ mediates H{sub 2}O{sub 2}-induced Ca{sup 2+} overload in cardiomyocytes. •miR-145 can inhibit Ca{sup 2+} overload. •A luciferase assay confirms that miR-145 functions as a CaMKIIδ-targeting miRNA. •Overexpression of miR-145 regulates CaMKIIδ-related genes and ameliorates apoptosis. -- Abstract: A change in intracellular free calcium (Ca{sup 2+}) is a common signaling mechanism of reperfusion-induced cardiomyocyte death. Calcium/calmodulin dependent protein kinase II (CaMKII) is a critical regulator of Ca{sup 2+} signaling and mediates signaling pathways responsible for functions in the heart including hypertrophy, apoptosis, arrhythmia, and heart disease. MicroRNAs (miRNA) are involved in the regulation of cell response, including survival, proliferation, apoptosis, and development. However, the roles of miRNAs in Ca{sup 2+}-mediated apoptosis of cardiomyocytes are uncertain. Here, we determined the potential role of miRNA in the regulation of CaMKII dependent apoptosis and explored its underlying mechanism. To determine the potential roles of miRNAs in H{sub 2}O{sub 2}-mediated Ca{sup 2+} overload, we selected and tested 6 putative miRNAs that targeted CaMKIIδ, and showed that miR-145 represses CaMKIIδ protein expression and Ca{sup 2+} overload. We confirmed CaMKIIδ as a direct downstream target of miR-145. Furthermore, miR-145 regulates Ca{sup 2+}-related signals and ameliorates apoptosis. This study demonstrates that miR-145 regulates reactive oxygen speciesmore » (ROS)-induced Ca{sup 2+} overload in cardiomyocytes. Thus, miR-145 affects ROS-mediated gene regulation and cellular injury responses.« less
- Published
- 2013
16. Up-regulation of miR-26a promotes apoptosis of hypoxic rat neonatal cardiomyocytes by repressing GSK-3β protein expression
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Chang Yeon Lee, Se-Yeon Lee, Jun-Hee Park, Eunmi Choi, Jong Hui Suh, Min-Ji Cha, Byeong-Wook Song, Cheesoon Yoon, Ki-Chul Hwang, Sun Hee Lee, and Onju Ham
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Population ,Biophysics ,Apoptosis ,Biology ,Biochemistry ,Gene Expression Regulation, Enzymologic ,Rats, Sprague-Dawley ,Glycogen Synthase Kinase 3 ,Downregulation and upregulation ,Annexin ,microRNA ,Animals ,Myocytes, Cardiac ,education ,Molecular Biology ,GSK3B ,Cells, Cultured ,chemistry.chemical_classification ,Regulation of gene expression ,education.field_of_study ,Reactive oxygen species ,Glycogen Synthase Kinase 3 beta ,Cell Biology ,Cell Hypoxia ,Rats ,Up-Regulation ,Cell biology ,MicroRNAs ,chemistry ,Reactive Oxygen Species ,Signal Transduction - Abstract
Myocardial ischemia is the major cause of morbidity and mortality due to cardiovascular diseases. This disease is a severe stress condition that causes extensive biochemical changes which trigger cardiac cell death. Stress conditions such as deprivation of glucose and oxygen activate the endoplasmic reticulum in the cytoplasm of cells, including cardiomyocytes, to generate and propagate apoptotic signals in response to these conditions. microRNAs (miRNAs) are a class of small non-coding RNAs that mediate posttranscriptional gene silencing. The miRNAs play important roles in regulating cardiac physiological and pathological events such as hypertrophy, apoptosis, and heart failure. However, the roles of miRNAs in reactive oxygen species (ROS)-mediated injury on cardiomyocytes are uncertain. In this study, we identified at the apoptotic concentration of H2O2, miR-26a expression was increased. To determine the potential roles of miR-26a in H2O2-mediated cardiac apoptosis, miR-26a expression was regulated by a miR-26a or an anti-miR-26a. Overexpression of miR-26a increased apoptosis as determined by upregulation of Annexin V/PI positive cell population, caspase-3 activity and expression of pro-apoptotic signal molecules, whereas inhibition of miR-26a reduced apoptosis. We identified GSK3B as a direct downstream target of miR-26a. Furthermore, miR-26a attenuated viability and increased caspase-3 activity in normal cardiomyocytes. This study demonstrates that miR-26a promotes ROS-induced apoptosis in cardiomyocytes. Thus, miR-26a affects ROS-mediated gene regulation and cellular injury response.
- Published
- 2012
17. The role of microRNA-23b in the differentiation of MSC into chondrocyte by targeting protein kinase A signaling
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Ki-Chul Hwang, Eunmi Choi, Chang Youn Lee, Yangsoo Jang, Soyeon Lim, Se-Yeon Lee, Chang Hyun Lee, Il-Kwon Kim, Onju Ham, Woochul Chang, Byeong-Wook Song, Jun-Hee Park, Min Ji Cha, and Soonhag Kim
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Cellular differentiation ,Blotting, Western ,Biophysics ,Bioengineering ,Real-Time Polymerase Chain Reaction ,Chondrocyte ,Biomaterials ,Chondrocytes ,medicine ,Humans ,Protein kinase A signaling ,Protein kinase A ,Cells, Cultured ,Aggrecan ,Sulfonamides ,Reverse Transcriptase Polymerase Chain Reaction ,Chemistry ,Mesenchymal stem cell ,Cell Differentiation ,Transfection ,Isoquinolines ,Chondrogenesis ,Cyclic AMP-Dependent Protein Kinases ,Immunohistochemistry ,Molecular biology ,Cell biology ,MicroRNAs ,medicine.anatomical_structure ,Mechanics of Materials ,Ceramics and Composites ,Signal Transduction - Abstract
Chondrogenic differentiation of mesenchymal stem cells (MSCs) is critical for successful cartilage regeneration. Several methods have been developed to attempt to chondrogenic differentiation, because chondrogenic differentiated cells can form stable cartilage and induce expression of a cartilage-specific phenotype. In this study, we found that both H-89 and microRNA-23b induced differentiation into chondrocyte of hMSCs through down-regulation of protein kinase A (PKA) signaling. The small molecule, H-89, was identified by PCA analysis as a potential mediator of chondrogenic differentiation. H-89 induced the expression of the chondrocyte marker, aggrecan, as well as miR-23b. We searched that miR-23b regulates protein level of PKA. When miR-23b was transfected into hMSCs, chondrogenic differentiation was induced. We confirmed the target of miR-23b using a reporter gene assay. Furthermore, not only H-89 or miR-23b-treated cells, but also cell co-treated with H-89 and miR-23b differentiated into chondrocytes. Our results indicate that H-89 induces the expression of endogenous miR-23b, thereby inducing chondrogenic differentiation by negatively inhibition of PKA signaling.
- Published
- 2012
18. Interleukin 10 polymorphisms differentially influence the risk of gastric cancer in East Asians and Caucasians
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Seonwoo Kim, Jong-Won Kim, Min-Ji Kim, Kyung A. Lee, Jun Hee Park, and Hong-Hee Won
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Immunology ,Population ,India ,Single-nucleotide polymorphism ,Biology ,Polymorphism, Single Nucleotide ,Biochemistry ,White People ,Asian People ,Gene Frequency ,Risk Factors ,Stomach Neoplasms ,Polymorphism (computer science) ,Republic of Korea ,Genotype ,Humans ,Immunology and Allergy ,Genetic Predisposition to Disease ,Allele ,education ,Molecular Biology ,Allele frequency ,Alleles ,Genetic association ,Genetics ,education.field_of_study ,Polymorphism, Genetic ,Hematology ,Odds ratio ,Interleukin-10 - Abstract
Background: Although a number of association studies of gastric cancer (GC) risk have been conducted worldwide, their results have been inconsistent among different populations. The association between GC incidence and Helicobacter pylori ( H. pylori ) infection is somewhat of an enigma that has yet to be clearly explained. Geographically-restricted positive selection due to unique environmental pressures often result in large allele frequency differences between populations. Thus, population differences need to be investigated when attempting to identify genes that contribute to phenotypes that differ greatly between populations. Methods: We analyzed population differences in 18 polymorphisms of 12 GC-associated or immune response-related genes from 3 ethnic groups comprising 50 Koreans, 46 Indians, and 60 Caucasians; these groups differed in H. pylori seropositivity and susceptibility to GC. Results: An interleukin 10 ( IL10 ) polymorphism demonstrated a significantly different genotype distribution ( F ST = 0.306, P = 0.014), indicating a large difference between the Korean and Caucasian populations. The odds ratio of IL10 polymorphism allele between the populations was 38.32 (95% confidence interval, 11.49–127.83). Conclusion: This finding, taken together with previous evidence, provides a possible explanation for previous discrepant association results and supports the idea that IL10 gene polymorphisms can differentially affect GC development among populations.
- Published
- 2010
19. Lipoblastoma arising from the submandibular region
- Author
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Jun Hee Park, Nam-Yong Do, Ji Yun Choi, and Sung Il Cho
- Subjects
Male ,Chin ,Pathology ,medicine.medical_specialty ,Soft mass ,business.industry ,Remission Induction ,Infant ,General Medicine ,Anatomy ,medicine.disease ,Trunk ,Benign tumor ,Diagnosis, Differential ,Head and Neck Neoplasms ,Pediatrics, Perinatology and Child Health ,medicine ,Humans ,Submandibular area ,Surgery ,Lipoblastoma ,Lipoma ,Tomography, X-Ray Computed ,business - Abstract
A lipoblastoma is a rare, benign tumor arising from embryonic white fat. The tumors occur primarily in infancy and early childhood and commonly arise from the limbs and the trunk, but neck involvement is extremely rare. Our case arose in a 22-month-old male presenting with a rapidly enlarging soft mass in the right submandibular area. Lipoblastoma was diagnosed by histologic evaluation, the mass was completely removed, and there was no recurrence at 1-year follow-up.
- Published
- 2008
20. Microrna-365 inhibits the proliferation of vascular smooth muscle cells by targeting cyclin d1
- Author
-
Ki-Chul Hwang, Jiyun Lee, Chang Yeon Lee, Se-Yeon Lee, Minji Seung, Eunhyun Choi, Jun-Hee Park, Pil-Ki Min, Hyuck Moon Kwon, Hyang-Hee Seo, Onju Ham, Eunmi Choi, and Myung-Hyun Kim
- Subjects
Cyclin D1 ,Vascular smooth muscle ,business.industry ,Chemistry ,microRNA ,Cancer research ,Medicine ,business ,Cardiology and Cardiovascular Medicine ,Cell biology - Published
- 2014
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