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Choi JW, Nahm H, Shin JE, Kim CH. Temporomandibular joint herniation into the middle ear: A rare cause of mastication-induced tinnitus. Radiol Case Rep 2019; 15:125-127. [PMID: 31798759 PMCID: PMC6881616 DOI: 10.1016/j.radcr.2019.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 10/25/2019] [Accepted: 10/26/2019] [Indexed: 11/20/2022] Open
Abstract
A 75-year-old patient complained of mastication-induced clicking tinnitus on the left side, and otoendoscopic examination revealed that the left tympanic membraneTM was outwardly bulged by clenching her teeth. Temporal bone computed tomography demonstrated that the posteromedial bony wall of the glenoid was partially dehiscent, allowing herniation of soft tissue contents of temporomandibular joint into the middle ear. Increased middle ear pressure due to soft tissue herniation can induce left tympanic membrane bulging and accompanying clicking tinnitus. Herniation of temporomandibular joint soft tissue into the middle ear should be considered as a differential diagnosis when clicking tinnitus is evoked by mastication.
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Kwon HY, Kim NJ, Lee CK, Yoon HG, Choi JW, Won C. An innovative magnetic state generator using machine learning techniques. Sci Rep 2019; 9:16706. [PMID: 31723230 PMCID: PMC6853879 DOI: 10.1038/s41598-019-53411-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 10/28/2019] [Indexed: 12/02/2022] Open
Abstract
We propose a new efficient algorithm to simulate magnetic structures numerically. It contains a generative model using a complex-valued neural network to generate k-space information. The output information is hermitized and transformed into real-space spin configurations through an inverse fast Fourier transform. The Adam version of stochastic gradient descent is used to minimize the magnetic energy, which is the cost of our algorithm. The algorithm provides the proper ground spin configurations with outstanding performance. In model cases, the algorithm was successfully applied to solve the spin configurations of magnetic chiral structures. The results also showed that a magnetic long-range order could be obtained regardless of the total simulation system size.
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Lee SH, Hosseindoust A, Laxman Ingale S, Rathi PC, Yoon SY, Choi JW, Kim JS. Thermostable xylanase derived from Trichoderma citrinoviride increases growth performance and non-starch polysaccharide degradation in broiler chickens. Br Poult Sci 2019; 61:57-62. [PMID: 31559842 DOI: 10.1080/00071668.2019.1673316] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
1. The aim of this trial was to determine the optimal supplementation level of a xylanase enzyme from Trichoderma citrinoviride on growth performance, apparent ileal and total tract nutrient retention, intestinal morphology, and intestinal concentration of volatile fatty acids in broiler chickens.2. A total of 600 broiler chickens (Ross 308) of mixed sex were randomly allotted to four treatments, on the basis of similar body weight. The dietary treatments were made from a corn-wheat-soy based diet supplemented with either 0, 3750, 7500, or 11 250 XU/kg xylanase and were fed to 32 d of age.3. A linear response to increasing dietary xylanase was demonstrated for overall weight gain (P < 0.05) and feed conversion ratio (P < 0.05). The apparent total tract digestibility of dry matter and gross energy, and the coefficient of apparent ileal digestibility (CIAD) of N and soluble non-starch polysaccharides were linearly improved when xylanase was added to the diet (P < 0.05). Moreover, a linear increase (P < 0.05) was observed in the CIAD of Arg, Lys, and Try with increasing dietary levels of xylanase.4. The viscosity of digesta in ileum was linearly decreased when dietary xylanase level increased (P < 0.05).5. An increase in villus height of the duodenum and jejunum were observed with increasing dietary levels of xylanase (linear, P < 0.05).6. Overall, the results showed that the effects of dietary xylanase supplementation on broiler performance was determined through effects on nutrient availability and intestinal morphology.
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Ahn YH, Seok PR, Oh SJ, Choi JW, Shin JH. A Study on the Protective Effect of Antioxidants on Damage Induced by Liver Ischemia/Repefusion in a Rat Model. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2019. [DOI: 10.15324/kjcls.2019.51.3.370] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Byun MR, Kim CH, Lee HS, Choi JW, Lee SK. Repurposing of ginseng extract as topoisomerase I inhibitor based on the comparative analysis of gene expression patterns. PHYTOCHEMISTRY 2019; 164:223-227. [PMID: 31181353 DOI: 10.1016/j.phytochem.2019.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 03/25/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Repositioning of plant extracts and chemical drugs can accelerate drug development. However, its success rate may depend on what the clue is for the repositioning. Recently, repositioning based on correction of unwarranted gene expression pattern has suggested the possibility of new drug development. Here, we designed a similar method for the repositioning of nutraceutical ginseng (Panax ginseng C.A.Mey.), which is one of the most validated natural therapeutic products for various diseases. We analyzed ginseng-induced gene expression profiles using the connectivity map algorithm, which is a database that connects diseases, chemical drugs, and gene expression. Ginseng was predicted to show the same effects as those of topoisomerase I inhibitors. In a subsequent in vitro assay, ginseng extract unwound coiled or supercoiled DNA, an effect comparable to that of the topoisomerase I inhibitor, camptothecin. Furthermore, ginseng extract induced synthetic lethality with suppression of the Werner syndrome gene. The collected data implicate ginseng as a candidate antitumor agent owing to its topoisomerase I inhibitory activity and further validate the usefulness of differentially expressed gene similarity-based repurposing of other natural products.
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Kim DY, Jung WS, Choi JW, Choung J, Kim HG. Evaluating Tissue Contrast and Detecting White Matter Injury in the Infant Brain: A Comparison Study of Synthetic Phase-Sensitive Inversion Recovery. AJNR Am J Neuroradiol 2019; 40:1406-1412. [PMID: 31345940 DOI: 10.3174/ajnr.a6135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Accepted: 06/17/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Synthetic MR imaging enables the acquisition of phase-sensitive inversion recovery images. The aim of this study was to compare the image quality of synthetic phase-sensitive inversion recovery with that of other sequences in infants. MATERIALS AND METHODS Brain MR imaging with 3D T1-weighted fast-spoiled gradient recalled, synthetic T1WI, and synthetic phase-sensitive inversion recovery of 91 infants was compared. Contrast between unmyelinated WM and myelinated WM and between unmyelinated WM and cortical GM was calculated. Qualitative evaluation of image quality and myelination degree was performed. In infants with punctate white matter injuries, the number of lesions was compared. RESULTS The contrast between unmyelinated WM and myelinated WM was higher in synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled or synthetic T1WI (P < .001). Compared with synthetic T1WI, synthetic phase-sensitive inversion recovery showed higher gray-white matter differentiation (P < .001) and myelination degree in the cerebellar peduncle (P < .001). The number of detected punctate white matter injuries decreased with synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled sequences (1.2 ± 3.2 versus 3.4 ± 3.6, P = .001). CONCLUSIONS Synthetic phase-sensitive inversion recovery has the potential to improve tissue contrast and image quality in the brain MR imaging of infants. However, we have to be aware that synthetic phase-sensitive inversion recovery has limited value when assessing punctate white matter injuries compared with 3D fast-spoiled gradient recalled imaging.
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Woo HC, Choi JW, Lee JS, Lee CL. Determination of complex dielectric function of CH 3NH 3PbBr 3 perovskite cubic colloidal quantum dots by modified iterative matrix inversion method. OPTICS EXPRESS 2019; 27:20098-20106. [PMID: 31510110 DOI: 10.1364/oe.27.020098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/24/2019] [Indexed: 06/10/2023]
Abstract
Recent advances in lead halide perovskite quantum dots appeal with their potential in various optoelectronic devices such as photovoltaics, photodetectors, light-emitting diodes (LEDs) and lasers. However, lack of information on the intrinsic optical properties of lead halide perovskite quantum dots (QDs) lags the progress in device performances and further development in various applications. In this letter, the complex dielectric function of CH3NH3PbBr3 perovskite cubic colloidal QDs was determined from the UV-Vis absorption by using a modified iterative matrix inversion (IMI) method. The modified IMI method takes into account the dilute solution with cubic inclusions, while the conventional method only considers spherical or elliptical inclusions by Maxwell-Garnett (MG) effective medium theory. In addition, singly subtractive Kramer Kronig (SSKK) relations have also been considered to compensate for possible errors arising from the finite wavelength range of the experimental absorption data.
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Wattanasatesiri T, Kim HC, Choi JW, Lee JH, Joo I, Hur S, Lee M, Jae HJ, Chung JW. Cone-Beam CT-Guided Chemoembolization in Patients with Complete Response after Previous Chemoembolization but Subsequent Elevated α-Fetoprotein without Overt Hepatocellular Carcinoma. J Vasc Interv Radiol 2019; 30:1273-1280. [PMID: 31235410 DOI: 10.1016/j.jvir.2019.03.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 03/10/2019] [Accepted: 03/17/2019] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To evaluate the performance of C-arm computed tomography (CT)-guided chemoembolization in patients with hepatocellular carcinoma (HCC) with serum α-fetoprotein (AFP) level > 20 ng/mL but with no overt tumor on CT and/or magnetic resonance imaging. MATERIALS AND METHODS From May 2010 to May 2017, 34 patients with HCC (25 men and 9 women; mean age, 59.7 y) who had elevated serum AFP levels (> 20 ng/mL) but no overt tumor on 6-mo imaging studies and had shown complete response (CR) after previous chemoembolization underwent C-arm CT-guided conventional chemoembolization. Three radiologists retrospectively reviewed the imaging studies (preprocedural images, C-arm CT scans, and follow-up images) in consensus, and clinical data including AFP levels were retrospectively obtained. Tumor detection by C-arm CT and treatment response after chemoembolization were assessed. RESULTS HCC was imaged at the time of chemoembolization in 24 of 34 patients (70.6%). C-arm CT detected tumors in 25 patients (73.5%); 23 detections were true positives, 2 were false positives, and 1 was a false negative (diaphragm metastasis). Among the 23 patients with true-positive results, the first follow-up enhanced imaging studies showed CR (n = 17), partial response (n = 1), progressive disease (n = 4), and indeterminate status (n = 1; treated by percutaneous ethanol injection). CONCLUSIONS C-arm CT-guided chemoembolization may help to detect and treat recurrent tumors in patients who have shown CR after previous chemoembolization but subsequently, during follow-up surveillance, had serum AFP levels > 20 ng/mL without an overt tumor evident on imaging studies.
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Park HS, Choi JW. Combined surgical approach to intralabyrinthine schwannoma. Eur Ann Otorhinolaryngol Head Neck Dis 2019; 137:223-226. [PMID: 31208878 DOI: 10.1016/j.anorl.2018.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 09/11/2018] [Accepted: 09/27/2018] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Intralabyrinthine schwannoma (ILS) is a tumor originating from the Schwann cells in the inner ear. Various surgical approaches can be used for the resection of ILS. The aim of this report is to describe a case involving a 60-year-old man who was treated successfully with a combined surgical approach. CASE REPORT The patient underwent a combined microscopic (transmastoid labyrinthectomy) and endoscopic procedure for surgical excision of ILS involving the vestibule and the lower half of the cochlear basal turn. The combined surgical technique enabled a complete removal of the ILS without removal of the unaffected cochlea as well as the external auditory canal. Besides additional exclusion of the middle ear, blind-sac closure of the external auditory canal and cavity obliteration were avoided. No postoperative complications were observed. DISCUSSION A combined microscopic and endoscopic approach to surgery enables removal of the ILS involving the vestibule and the lower half of the cochlear basal turn while helping to reduce surgical radicality.
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Park D, Choi EJ, Weon KY, Lee W, Lee SH, Choi JS, Park GH, Lee B, Byun MR, Baek K, Choi JW. Non-Invasive Photodynamic Therapy against -Periodontitis-causing Bacteria. Sci Rep 2019; 9:8248. [PMID: 31160615 PMCID: PMC6546788 DOI: 10.1038/s41598-019-44498-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 05/17/2019] [Indexed: 12/04/2022] Open
Abstract
Periodontitis is initiated by causative bacteria in the gingival sulcus. However, as the lesion is often deep and out of circulation system and biofilm is frequently formed on the bacteria cluster, use of antibacterial agents has been limited and the invasive method such as curettage is thought as an only treatment. Here we designed non-invasive photodynamic therapy (PDT), with the ointment which leads a photosensitizer deliverable into gingival sulcus. We assessed whether 650 nm light-emitting-diode (LED) penetrates the 3-mm soft tissue and effectively activates a photosensitizer toluidine-blue-O (TBO) through the thickness to remove Porphyromonas gingivalis and Fusobacterium nucleatum species. The oral ointment formulation was optimized to efficiently deliver the photosensitizer into gingival sulcus and its efficacy of PDT was evaluated in in vitro and in vivo models. Four weeks of TBO-formulation mediated-PDT treatment significantly attenuated periodontitis-induced alveolar bone loss and inflammatory cytokines production in rats. These results confirm that a 650 nm LED indeed penetrates the gingiva and activates our TBO formulation which is sufficiently delivered to, and retained within, the gingival sulcus; thus, it effectively kills the bacteria that reside around the gingival sulcus. Collectively, TBO-mediated PDT using LED irradiation has potential as a safe adjunctive procedure for periodontitis treatment.
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Byun MR, Lee DH, Jang YP, Lee HS, Choi JW, Lee SK. Repurposing natural products as novel HDAC inhibitors by comparative analysis of gene expression profiles. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 59:152900. [PMID: 30974310 DOI: 10.1016/j.phymed.2019.152900] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 03/13/2019] [Accepted: 03/21/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Extracts derived from natural products have been used to produce health supplements or therapeutic agents in oriental medicine. Although these extracts contain various bioactive compounds, their applications are generally limited to a few previously known diseases. To effectively expand their use for the treatment of other conditions, systematic analysis should be conducted for repurposing. PURPOSE The purpose of the present study was to investigate the new therapeutic efficacies of the Platycodon grandiflorum and ginseng extract using the CMAP-based gene expression analysis. METHODS In the present study, we analyzed the expression patterns of differentially expressed genes (DEGs) from extracts as the basis for drug repurposing. Cells were treated with extracts or single compounds derived from nine natural products. DEG analysis indicated that the gene expression patterns of cells treated with P. grandiflorum and ginseng extracts were highly similar to those of cells treated with different types of Histone deacetylase (HDAC) inhibitors. To identify the new mechanism of these extracts, we carried out cell viability assay, TUNEL assay, HDAC enzyme activity assay and immunoblot analysis. RESULTS In vitro experiments at the dose of 50 µg/ml of each extract did not affect cell death rate but significantly inhibited HDAC activity. Each extract was found to inhibit HDAC enzymatic activity and induce the expression of the p21. Furthermore, our results revealed that each extract stimulated cell death and inhibited cell proliferation. CONCLUSION These findings demonstrate the HDAC-inhibiting activity of P. grandiflorum and ginseng extracts and further validate the effectiveness of DEG similarity-based repurposing of natural products.
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Roh HG, Kim EY, Kim IS, Lee HJ, Park JJ, Lee SB, Choi JW, Jeon YS, Park M, Kim SU, Kim HJ. A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study. AJNR Am J Neuroradiol 2019; 40:946-953. [PMID: 31097431 DOI: 10.3174/ajnr.a6068] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/12/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion. MATERIALS AND METHODS From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested. RESULTS Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949). CONCLUSIONS We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.
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Seok PR, Oh SJ, Choi JW, Lim CR, Choi JR, Kim JH, Shin JH. The protective effects of Gastrodia elata Blume extracts on middle cerebral artery occlusion in rats. Food Sci Biotechnol 2019; 28:857-864. [PMID: 31093444 DOI: 10.1007/s10068-018-0516-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 10/27/2018] [Accepted: 11/14/2018] [Indexed: 11/27/2022] Open
Abstract
To investigate the effects of Gastrodia elata Blume (GEB) and 4-hydroxybenzyl alcohol (HBA) on brain damage, GEB or HBA was administered orally for 14 days before middle cerebral artery occlusion (MCAO). After 24 h reperfusion, the proportion of circling was significantly reduced in the GEB (79%) or HBA (69%) group compared to the MCAO group (100%) in the corner test, and the removal time in the adhesive removal test was significantly decreased in the GEB (117 ± 21.0 s) and HBA (101 ± 20.9 s) groups compared to the MCAO group (161 ± 12.6 s). GEB treatment significantly reduced infarct volume compared to the MCAO group. In the GEB and HBA group, necrosis of nerve cells in hippocampus and cortex, expressions of TNF-α and TUNEL positive cells were significantly reduced compared to the MCAO group. These results suggest that GEB and HBA prevents brain damage by anti-inflammatory and anti-apoptotic effects.
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Youn S, Choi JW, Lee JS, Kim J, Yang IH, Chang JH, Kim HC, Hwang JY. Acoustic Trapping Technique for Studying Calcium Response of a Suspended Breast Cancer Cell: Determination of Its Invasion Potentials. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2019; 66:737-746. [PMID: 30676954 DOI: 10.1109/tuffc.2019.2894662] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A noncontact single-beam acoustic trapping technique has proven to be a promising tool for cell manipulation and characterization that provide essential knowledge for a variety of biomedical applications. Here, we investigated cell characteristics as to whether the calcium responses of suspended breast cancer cells to different acoustic trapping forces are related to their invasiveness. For this, we combined a single-beam acoustic trapping system with a 30-MHz press-focused lithium niobate ultrasound transducer and an epifluorescence microscope. Using the system, intracellular calcium changes of suspended MDA-MB-231 (highly invasive) and MCF-7 (weakly invasive) cells were monitored while trapping the cells at different acoustic pressures. The results showed that a single suspended breast cancer cell isolated by the acoustic microbeam behaved differently on the calcium elevation in response to changes in acoustic trapping force, depending on its invasiveness. In particular, the MDA-MB-231 cells exhibited higher calcium elevation than MCF-7 cells when each cell was trapped at low acoustic pressure. Based on these results, we believe that the single-beam acoustic trapping technique has high potential as an alternative tool for determining the degree of invasiveness of suspended breast cancer cells.
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Chin SH, Choi JW, Woo HC, Kim JH, Lee HS, Lee CL. Realizing a highly luminescent perovskite thin film by controlling the grain size and crystallinity through solvent vapour annealing. NANOSCALE 2019; 11:5861-5867. [PMID: 30656325 DOI: 10.1039/c8nr09947b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Organometallic halide perovskite films were treated with novel facile solvent vapour annealing to control crystal grain size as well as the crystallinity of perovskite. As both polarity and vapour pressure of the treatment solvent for perovskite increase, luminance increases and the wavelength of the photoluminescence emission peak decreases due to enhanced crystallinity and reduced grain size.
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Choi JW, Cho N, Woo HC, Oh BM, Almutlaq J, Bakr OM, Kim SH, Lee CL, Kim JH. Correction: Investigation of high contrast and reversible luminescence thermochromism of the quantum confined Cs 4PbBr 6 perovskite solid. NANOSCALE 2019; 11:5770. [PMID: 30865201 DOI: 10.1039/c9nr90060h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Correction for 'Investigation of high contrast and reversible luminescence thermochromism of the quantum confined Cs4PbBr6 perovskite solid' by Jong H. Kim et al., Nanoscale, 2019, DOI: 10.1039/c8nr10223f.
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Choi JW, Cho N, Woo HC, Oh BM, Almutlaq J, Bakr OM, Kim SH, Lee CL, Kim JH. Investigation of high contrast and reversible luminescence thermochromism of the quantum confined Cs 4PbBr 6 perovskite solid. NANOSCALE 2019; 11:5754-5759. [PMID: 30834913 DOI: 10.1039/c8nr10223f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Thermochromism of organic/inorganic halide perovskites has attracted particular interest due to their potential applications as photoluminescence (PL)-based temperature sensors. However, despite the outstanding PL characteristics, their use as a thermochromic material in practical temperature ranges has been limited because of their poor thermal stability. In this study, we used the quantum confinement effect and exceptional PL quantum efficiency of the Cs4PbBr6 perovskite to demonstrate their high on/off ratio (20) and reversible PL thermochromism in the solid state in practical temperature ranges including room temperature (RT). Systematic photophysical and optical characterization studies, including exciton-phonon scattering, exciton binding energy, exciton decay dynamics, and crystal structure change, were performed to investigate the origin of this unique thermochromic PL property. The results showed that the efficient and highly reversible thermochromic PL emission of the Cs4PbBr6 perovskite is due to its desirable optical properties such as highly luminescent emission, efficient PL quenching at high temperatures, and thermally reversible structural changes.
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Yang HS, Kim J, Kim S, Eom NSA, Kang S, Han CS, Kim SH, Lim D, Lee JH, Park SH, Choi JW, Lee CL, Yoo B, Lim JH. Kerf-Less Exfoliated Thin Silicon Wafer Prepared by Nickel Electrodeposition for Solar Cells. Front Chem 2019; 6:600. [PMID: 30693277 PMCID: PMC6339913 DOI: 10.3389/fchem.2018.00600] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 11/20/2018] [Indexed: 11/13/2022] Open
Abstract
Ultra-thin and large-area silicon wafers with a thickness in the range of 20-70 μm, were produced by spalling using a nickel stressor layer. A new equation for predicting the thickness of the spalled silicon was derived from the Suo-Hutchinson mechanical model and the kinking mechanism. To confirm the reliability of the new equation, the proportional factor of stress induced by the nickel on the silicon wafer, was calculated. The calculated proportional factor of λ = 0.99 indicates that the thickness of the spalled silicon wafer is proportional to that of the nickel layer. A similar relationship was observed in the experimental data obtained in this study. In addition, the thickness of the stressor layer was converted to a value of stress as a guide when using other deposition conditions and materials. A silicon wafer with a predicted thickness of 50 μm was exfoliated for further analysis. In order to spall a large-area (150 × 150 mm2 or 6 × 6 in2) silicon wafer without kerf loss, initial cracks were formed by a laser pretreatment at a proper depth (50 μm) inside the exfoliated silicon wafer, which reduced the area of edge slope (kerf loss) from 33 to 3 mm2. The variations in thickness of the spalled wafer remained under 4%. Moreover, we checked the probability of degradation of the spalled wafers by using them to fabricate solar cells; the efficiency and ideality factor of the spalled silicon wafers were found to be 14.23%and 1.35, respectively.
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Kim YS, Kim Y, Choi JW, Oh HE, Lee JH. Genetic variants and risk of prostate cancer using pathway analysis of a genome-wide association study. Neoplasma 2019; 63:629-34. [PMID: 27268928 DOI: 10.4149/neo_2016_418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study explored candidate causal single nucleotide polymorphisms (SNPs) to clarify the biological mechanism of prostate cancer (PCa). Identify candidate Causal SNPs and Pathways (ICSNPathway) analysis was applied using a PCa genome-wide association study (GWAS) dataset that included 473,736 SNPs in 1151 cases of PCa and 1156 controls of European ancestry. Five candidate causal SNPs, three candidate causal genes, and two candidate causal pathways were identified using integrating linkage disequilibrium analysis, functional SNP annotation, and pathway-based analysis. The ICSNPathway analysis suggested three hypothetical mechanisms of PCa. The first was rs13112390, rs13112358, rs2048074 to nei-like DNA glycosylase 3 (NEIL3) gene to damaged DNA binding. The second was rs3087386 to REV1, DNA directed polymerase (REV1) gene to damaged DNA binding. The third was rs1063134 to potassium channel, inwardly rectifying subfamily J, member 4 (KCNJ4) gene to inward rectifier potassium channel activity.
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Kim YR, Yoo JK, Jeong CW, Choi JW. Correction to: Selective killing of circulating tumor cells prevents metastasis and extends survival. J Hematol Oncol 2019; 12:5. [PMID: 30626405 PMCID: PMC6327478 DOI: 10.1186/s13045-018-0688-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 11/25/2022] Open
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Byun MR, Lee SW, Paulson B, Lee S, Lee W, Lee KK, Kim YR, Kim JK, Choi JW. Micro-endoscopic In Vivo Monitoring in the Blood and Lymphatic Vessels of the Oral Cavity after Radiation Therapy. Int J Med Sci 2019; 16:1525-1533. [PMID: 31673245 PMCID: PMC6818205 DOI: 10.7150/ijms.36470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/23/2019] [Indexed: 11/30/2022] Open
Abstract
Radiotherapy, although used worldwide for the treatment of head, neck, and oral cancers, causes acute complications, including effects on vasculature and immune response due to cellular stress. Thus, the ability to diagnose side-effects and monitor vascular response in real-time during radiotherapy would be highly beneficial for clinical and research applications. In this study, recently-developed fluorescence micro-endoscopic technology provides non-invasive, high-resolution, real-time imaging at the cellular level. Moreover, with the application of high-resolution imaging technologies and micro-endoscopy, which enable improved monitoring of adverse effects in GFP-expressing mouse models, changes in the oral vasculature and lymphatic vessels are quantified in real time for 10 days following a mild localized single fractionation, 10 Gy radiotherapy treatments. Fluorescence micro-endoscopy enables quantification of the cardiovascular recovery and immune response, which shows short-term reduction in mean blood flow velocity, in lymph flow, and in transient immune infiltration even after this mild radiation dose, in addition to long-term reduction in blood vessel capacity. The data provided may serve as a reference for the expected cellular-level physiological, cardiovascular, and immune changes in animal disease models after radiotherapy.
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Park J, Choi JW, Kim W, Lee R, Woo HC, Shin J, Kim H, Son YJ, Jo JY, Lee H, Kwon S, Lee CL, Jung GY. Improvement of perovskite crystallinity by omnidirectional heat transfer via radiative thermal annealing. RSC Adv 2019; 9:14868-14875. [PMID: 35516303 PMCID: PMC9064265 DOI: 10.1039/c9ra01309a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/27/2019] [Indexed: 11/21/2022] Open
Abstract
As promising photo-absorbing materials for photovoltaics, organic–inorganic hybrid perovskite materials such as methylammonium lead iodide and formamidinium lead iodide, have attracted lots of attention from many researchers. Among the various factors to be considered for high power conversion efficiency (PCE) in perovskite solar cells (PSCs), increasing the grain size of perovskite is most important. However, it is difficult to obtain a highly crystalline perovskite film with large grain size by using the conventional hot-plate annealing method because heat is transferred unidirectionally from the bottom to the top. In this work, we presented radiative thermal annealing (RTA) to improve the structural and electrical properties of perovskite films. Owing to the omnidirectional heat transfer, swift and uniform nuclei formation was possible within the perovskite film. An average grain size of 500 nm was obtained, which is 5 times larger than that of the perovskite film annealed on a hot-plate. This perovskite film led to an enhancement of photovoltaic performance of PSCs. Both short-circuit current density and PCE of the PSCs prepared by RTA were improved by 10%, compared to those of PSCs prepared by hot-plate annealing. Perovskite solar cells produced by RTA demonstrate superior photovoltaic (PV) performances than those annealed on a hot plate.![]()
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98
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Choi JW, Moon WJ. Gadolinium Deposition in the Brain: Current Updates. Korean J Radiol 2018; 20:134-147. [PMID: 30627029 PMCID: PMC6315073 DOI: 10.3348/kjr.2018.0356] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 09/21/2018] [Indexed: 12/21/2022] Open
Abstract
Gadolinium-based contrast agents (GBCAs) are commonly used for enhancement in MR imaging and have long been considered safe when administered at recommended doses. However, since the report that nephrogenic systemic fibrosis is linked to the use of GBCAs in subjects with severe renal diseases, accumulating evidence has suggested that GBCAs are not cleared entirely from our bodies; some GBCAs are deposited in our tissues, including the brain. GBCA deposition in the brain is mostly linked to the specific chelate structure of the GBCA: linear GBCAs were responsible for brain deposition in almost all reported studies. This review aimed to summarize the current knowledge about GBCA brain deposition and discuss its clinical implications.
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Lee SY, Choi JW, Lee JY, Kim DD, Kim HC, Cho HJ. Hyaluronic acid/doxorubicin nanoassembly-releasing microspheres for the transarterial chemoembolization of a liver tumor. Drug Deliv 2018; 25:1472-1483. [PMID: 29909706 PMCID: PMC6058484 DOI: 10.1080/10717544.2018.1480673] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 05/19/2018] [Accepted: 05/21/2018] [Indexed: 02/07/2023] Open
Abstract
Doxorubicin (DOX)-loaded, hyaluronic acid-ceramide (HACE) nanoassembly-releasing poly(lactic-co-glycolic acid) (PLGA) microspheres (MSs) were developed for transarterial chemoembolization (TACE) therapy of liver cancer. DOX/HACE MSs with a mean diameter of 27 μm and a spherical shape were prepared based on the modified emulsification method. Their in vitro biodegradability in artificial biological fluids was observed. A more sustained drug release pattern was observed from DOX/HACE MS than from DOX MS at pH 7.4. The cellular internalization efficiency of DOX of the DOX/HACE MS group was higher than that of the DOX MS group in liver cancer cells (HepG2 and McA-RH7777 cells), mainly due to CD44 receptor-mediated endocytosis of the released DOX/HACE nanoassembly. In both HepG2 and McA-RH7777 cells, the antiproliferation and apoptotic potentials of the DOX/HACE MS were significantly higher than those of the DOX MS (p < .05). Notably, in the McA-RH7777 tumor-implanted rat models, a better tumor growth suppression, a lower tumor viable portion, and a higher incidence of apoptosis were presented in the DOX/HACE MS group than in the DOX MS group after intra-arterial (IA) administration. DOX/HACE-based nanoassembly release from the DOX/HACE MS seems to elevate the cellular accumulation of DOX and its anticancer activities. The developed DOX/HACE MS can be used as a drug-loaded HA nanoassembly-releasing MS system for TACE therapy of liver cancer.
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Kim YR, Byun MR, Choi JW. Integrin α6 as an invasiveness marker for hepatitis B viral X-driven hepatocellular carcinoma. Cancer Biomark 2018; 23:135-144. [PMID: 30010110 DOI: 10.3233/cbm-181498] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Hepatitis B virus (HBV) accounts for more than 60% of hepatocellular carcinoma (HCC) cases. However, there is limited information about the features of HBV-driven HCC that differentiate it from other types of HCC. OBJECTIVE The aim of this study is to find a gene specific to HBV-driven HCC and understand its role during tumorigenesis. METHODS The differences in gene expression patterns were analyzed among patients with hepatitis virus-unrelated liver cirrhosis, and hepatitis C virus- and HBV-driven HCC. Genes expressed only in HBV patients were compared to genes of transgenic mice expressing hepatitis B viral X gene. RESULTS Integrin α6 was commonly overexpressed in both HBV-driven HCC patients and transgenic mice expressing viral X. This gene's activation induced overexpression of integrin α6, as well as formation of integrins α6β1 and α6β4, without changing the expression of non-integrin laminin receptors. Suppression of integrin α6 caused significant inhibition of tumor migration in vitro. CONCLUSIONS This study found a significant association between HBV and integrin α6, which may be responsible for early migration and invasion of HCC. Thus, integrin α6 is a predictive marker for tumor recurrence and invasiveness of HBV-driven HCC.
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