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Kim MS, Chung J, Kang JY, Choi JW. Transcanal endoscopic ear surgery for traumatic ossicular injury. Acta Otolaryngol 2020; 140:22-26. [PMID: 31707916 DOI: 10.1080/00016489.2019.1685682] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: Transcanal endoscopic ear surgery (TEES) for traumatic ossicular injuries (TOI) is not well studied.Objectives: To analyze the treatment outcomes of TEES for TOI.Material and methods: Retrospective case review of fifteen patients (15 ears) with TOI was performed. The patients underwent an either ossiculoplasty or stapes surgery according to status of the ossicular chain using ear endoscopes. Postoperative audiometric results and complications were analyzed.Results: All subjects demonstrated improvement in their air conduction threshold and air-bone gap (ABG). The mean preoperative air conduction threshold and ABG were 55.3 dB (SD: 12.8) and 33.0 dB (SD: 9.5), respectively. Postoperatively, the air conduction threshold and ABG significantly improved to 28.1 dB (SD: 16.0) and 8.1 dB (SD: 4.5), respectively. Separation of the incudomalleolar joint accompanied by defect of the tegmen, which was not discernible on preoperative imaging, could be identified without additional incision or mastoidectomy. No patients experienced complications or a sensorineural hearing loss. Conversion to open approach was not necessary for any of the 15 procedures performed.Conclusion and significance: TEES for TOI yielded favorable audiometric results without any complication. TEES can provide an alternative method to manage TOI with the advantage of avoidance of skin incisions and mastoidectomy.
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Gao N, Je SG, Im MY, Choi JW, Yang M, Li Q, Wang TY, Lee S, Han HS, Lee KS, Chao W, Hwang C, Li J, Qiu ZQ. Creation and annihilation of topological meron pairs in in-plane magnetized films. Nat Commun 2019; 10:5603. [PMID: 31811144 PMCID: PMC6898613 DOI: 10.1038/s41467-019-13642-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 11/18/2019] [Indexed: 11/10/2022] Open
Abstract
Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in chiral magnet Co8Zn9Mn3 raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii–Moriya interaction. A meron is one half of a skyrmion but whether a single meron pair can be created and stabilized remains a challenging question. Here, Gao et al. develop a method to create and stabilize individual pairs of merons in a continuous Py film by local vortex imprinting from Co disks.
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Lee G, Lee SG, Park HS, Kim BJ, Choi SJ, Choi JW. Clinical characteristics and associated factors of canal switch in benign paroxysmal positional vertigo. J Vestib Res 2019; 29:253-260. [DOI: 10.3233/ves-190667] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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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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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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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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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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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 HG, Lee JH, Choi JW, Han M, Gho SM, Moon Y. Multidelay Arterial Spin-Labeling MRI in Neonates and Infants: Cerebral Perfusion Changes during Brain Maturation. AJNR Am J Neuroradiol 2018; 39:1912-1918. [PMID: 30213808 DOI: 10.3174/ajnr.a5774] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/08/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Arterial spin-labeling with multiple postlabeling delays can correct transit times. We tried to evaluate CBF in neonates and infants using multidelay arterial spin-labeling. MATERIALS AND METHODS Multidelay arterial spin-labeling was applied to 13 preterm neonates (mean postmenstrual age, 34.9 weeks), 13 term-equivalent-age neonates (mean postmenstrual age, 39.2 weeks), and 6 infants (mean postmenstrual age, 57.8 weeks). Transit time-corrected CBF in the caudate, thalamus, frontal GM, occipital GM, frontal WM, and occipital WM was measured, and relative CBF compared with the whole-brain CBF was calculated. Inter- and intragroup comparisons were performed among the 3 age groups. A correlation and nonlinear regression analysis were performed between postmenstrual age and CBF. RESULTS Intergroup comparisons showed significantly higher whole-brain CBF in infants (38.3 mL/100 g/min) compared with preterm (15.5 mL/100 g/min) and term-equivalent-age (18.3 mL/100 g/min) neonates (P < .001). In the intragroup comparison, all 3 groups showed significantly higher relative CBF values in the occipital WM (63.6%-90.3%) compared with the frontal WM (46.3%-73.9%). In term-equivalent-age neonates, the occipital GM (120.8%) had significantly higher relative CBF values than the frontal GM (103.5%). There was a significant negative correlation between postmenstrual age and the relative CBF of the thalamus (r = - 0.449, P = .010). There were significant positive relationships between postmenstrual age and the relative CBF of the frontal WM (R 2 = 0.298, P = .001) and occipital WM (R 2 = 0.452, P < .001). CONCLUSIONS Multidelay arterial spin-labeling with transit time-corrected CBF showed developmental changes and regional differences of CBF in neonates and infants.
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Kang JY, Chung JH, Park HS, Park YH, Choi JW. Radiological parameters related to success of the round window approach in cochlear implantation: A retrospective study. Clin Otolaryngol 2018; 43:1535-1540. [DOI: 10.1111/coa.13207] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 07/03/2018] [Accepted: 08/02/2018] [Indexed: 12/01/2022]
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Lim YH, Choi YW, Park JY, Lee YG, Choi JW, Park HK, Cho SH, Cho SH. P4423Non-contact heart beat monitoring using impulse-radio ultra-wide band radar technology. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p4423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Song K, Park KW, Heo JH, Song IC, Park YH, Choi JW. Clinical Characteristics of Temporal Bone Metastases. Clin Exp Otorhinolaryngol 2018; 12:27-32. [PMID: 29909612 PMCID: PMC6315217 DOI: 10.21053/ceo.2018.00171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 05/04/2018] [Indexed: 12/02/2022] Open
Abstract
Objectives The purposes of this study were to evaluate the clinical characteristics of temporal bone metastasis (TBM) and to determine whether the characteristics differed according to primary malignancy. Methods We retrospectively analyzed data on 20 patients diagnosed with TBM between January 2000 and January 2017. Demographics, the period from diagnosis of primary malignancy to TBM diagnosis, the period from TBM diagnosis to death, the type and staging of primary malignancy, otologic manifestations, and TBM sites were assessed. After the primary malignancies were divided into solid cancers and hematologic malignancies, each parameter was compared between the two groups. Results The most common primary malignancy with TBM was lung cancer (45%). The most common otologic symptoms and signs were facial palsy (30.5%) and hearing loss (30.5%). The temporal squama (23%) and the facial nerve (20%) were the most commonly involved. Most TBMs occurred late in the disease process after the primary malignancy first metastasized to other organs. Hematologic malignancies metastasized significantly more frequently to the external auditory canal and the middle ear/mastoid compared to solid cancers (P=0.001 and P=0.004, respectively). Conclusion If otologic manifestations such as facial palsy and hearing loss are presented in patients at advanced stages of malignancy, TBM of primary malignancy should be suspected. In addition, hematologic malignancies tend to metastasize to the external auditory canal and the middle ear cleft more commonly than solid cancers do.
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Huiting LN, Samaha Y, Zhang GL, Roderick JE, Li B, Anderson NM, Wang YW, Wang L, Laroche F, Choi JW, Liu CT, Kelliher MA, Feng H. UFD1 contributes to MYC-mediated leukemia aggressiveness through suppression of the proapoptotic unfolded protein response. Leukemia 2018; 32:2339-2351. [PMID: 29743725 PMCID: PMC6202254 DOI: 10.1038/s41375-018-0141-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 03/11/2018] [Accepted: 03/15/2018] [Indexed: 02/07/2023]
Abstract
Despite the pivotal role of MYC in tumorigenesis, the mechanisms by which it promotes cancer aggressiveness remain incompletely understood. Here we show that MYC transcriptionally upregulates the ubiquitin fusion degradation 1 (UFD1) gene in T-cell acute lymphoblastic leukemia (T-ALL). Allelic loss of ufd1 in zebrafish induces tumor-cell apoptosis and impairs MYC-driven T-ALL progression but does not affect general health. As the E2 component of an endoplasmic reticulum (ER)-associated degradation (ERAD) complex, UFD1 facilitates the elimination of misfolded/unfolded proteins from the ER. We found that UFD1 inactivation in human T-ALL cells impairs ERAD, exacerbates ER stress, and induces apoptosis. Moreover, we show that UFD1 inactivation promotes the proapoptotic unfolded protein response (UPR) mediated by protein kinase RNA-like ER kinase (PERK). This effect is demonstrated by an upregulation of PERK and its downstream effector C/EBP homologous protein (CHOP), as well as a downregulation of BCL2 and BCLxL. Indeed, CHOP inactivation or BCL2 overexpression is sufficient to rescue tumor-cell apoptosis induced by UFD1 knockdown. Together, our studies identify UFD1 as a critical regulator of the ER stress response and a novel contributor to MYC-mediated leukemia aggressiveness, with implications for targeted therapy in T-ALL and likely other MYC-driven cancers.
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Kang SP, Kim NJ, Kwon HY, Choi JW, Min BC, Won C. The spin structures of interlayer coupled magnetic films with opposite chirality. Sci Rep 2018; 8:2361. [PMID: 29402938 PMCID: PMC5799310 DOI: 10.1038/s41598-018-20800-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/22/2018] [Indexed: 11/21/2022] Open
Abstract
Using Monte-Carlo simulations and micromagnetic simulations, we reveal how the spin structural correlation and the skyrmion dynamics are affected by the interlayer coupling in a chiral magnetic bilayer system, in which the two layers have opposite chirality. The interaction through interlayer coupling between chiral magnetic structures influences the static and dynamics properties profoundly. The competition between the Dzyaloshinskii-Moriya interaction and the interlayer interaction allows multiple magnetic structures to be energetically stable, which includes sole skyrmion states (skyrmion appears in only one of the layers) and skyrmion pair states (coupled skyrmions in top and bottom layers). When current driven spin transfer torques are applied to each state, the sole skyrmion state is mainly propelled by a spin transfer torque causing the skyrmion hall effect, but the skyrmion pair state is propelled by a torque from skyrmion-skyrmion interaction and not influenced by the skyrmion hall effect. Also upon application of an external magnetic field, we found the skyrmions in a skyrmion pair state extinguish in an exclusive way, as the annihilation of a skyrmion in one of the layers stabilizes the once paired skyrmion in the other layer, i.e. the skyrmion lattice sites have only one skyrmion in either layer.
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Kim YK, Choi JW, Kim HJ, Kim HY, Park GM, Ko YH, Cha J, Kim ST. Melanoma of the Sinonasal Tract: Value of a Septate Pattern on Precontrast T1-Weighted MR Imaging. AJNR Am J Neuroradiol 2018; 39:762-767. [PMID: 29371259 DOI: 10.3174/ajnr.a5539] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 11/20/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND PURPOSE Various tumors of the sinonasal tract can exhibit high signal intensity on T1WI. The purpose of this study was to determine the value of a septate pattern on precontrast T1WI for diagnosing sinonasal melanoma. MATERIALS AND METHODS Retrospectively, 3 observers independently reviewed MR images of 31 histologically proved sinonasal melanomas with special attention to the presence or absence of a septate pattern on precontrast T1WI, defined as alternating hyperintense and hypointense striations on precontrast T1WI. For comparison, we evaluated the prevalence of a septate pattern on precontrast T1WI in 106 nonmelanomatous sinonasal malignant tumors with 16 different histologic types. We also tried to identify the histopathologic features responsible for the septate pattern on precontrast T1WI. RESULTS Twenty-seven (87.1%) of 31 sinonasal melanomas showed hyperintense foci on T1WI, among which a septate pattern on precontrast T1WI was seen in 23 (74.2%), while 22 (20.8%) of 106 nonmelanomatous malignant tumors demonstrated hyperintense foci on T1WI, among which only 3 (2.8%) showed a septate pattern on precontrast T1WI. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of a septate pattern on precontrast T1WI for the diagnosis of sinonasal melanoma were 74%, 97%, 88%, 93%, and 92%, respectively. Although limited due to the retrospective nature, 4 of 23 histologically reviewed sinonasal melanomas revealed an uneven distribution of melanin with alternating melanin and fibrous bands within the tumors. CONCLUSIONS A septate pattern on precontrast T1WI might be an adjunctive imaging finding for the diagnosis of sinonasal melanoma. This might be attributed histologically to an uneven distribution of melanin and hemorrhage within the tumors.
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Lim JM, Choi JH, Choi JW, Yun JW, Park TJ, Park JP. Cloning, Expression, and Production of Xylo-Oligosaccharides by Using a Newly Screened Xylanase Isolated from Bovine Rumen. Appl Biochem Biotechnol 2017; 184:1347-1357. [PMID: 29027104 DOI: 10.1007/s12010-017-2623-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 10/02/2017] [Indexed: 10/18/2022]
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Jeong WS, Choi JW, Kim DY, Lee JY, Kwon SM. Corrigendum to "Can a surgery-first orthognathic approach reduce the total treatment time?" [Int. J. Oral Maxillofac. Surg. 46 (2017) 473-482]. Int J Oral Maxillofac Surg 2017. [PMID: 28623044 DOI: 10.1016/j.ijom.2017.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Bak SH, Roh HG, Moon WJ, Choi JW, An HS. Appropriate Minimal Dose of Gadobutrol for 3D Time-Resolved MRA of the Supra-Aortic Arteries: Comparison with Conventional Single-Phase High-Resolution 3D Contrast-Enhanced MRA. AJNR Am J Neuroradiol 2017; 38:1383-1390. [PMID: 28473338 DOI: 10.3174/ajnr.a5176] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/13/2017] [Indexed: 01/25/2023]
Abstract
BACKGROUND AND PURPOSE The development of nephrogenic systemic fibrosis and neural tissue deposition is gadolinium dose-dependent. The purpose of this study was to determine the appropriate minimal dose of gadobutrol with time-resolved MRA to assess supra-aortic arterial stenosis with contrast-enhanced MRA as a reference standard. MATERIALS AND METHODS Four hundred sixty-two consecutive patients underwent both standard-dose contrast-enhanced MRA and low-dose time-resolved MRA and were classified into 3 groups; group A (a constant dose of 1 mL for time-resolved MRA), group B (2 mL), or group C (3 mL). All studies were independently evaluated by 2 radiologists for image quality by using a 5-point scale (from 0 = failure to 4 = excellent), grading of arterial stenosis (0 = normal, 1 = mild [<30%], 2 = moderate [30%-69%], 3 = severe to occlusion [≥70%]), and signal-to-noise ratio. RESULTS The image quality of time-resolved MRA was similar to that of contrast-enhanced MRA in groups B and C, but it was inferior to contrast-enhanced MRA in group A. For the grading of arterial stenosis, there was an excellent correlation between contrast-enhanced MRA and time-resolved MRA (R = 0.957 for group A, R = 0.988 for group B, R = 0.991 for group C). The SNR of time-resolved MRA tended to be lower than that of contrast-enhanced MRA in groups A and B. However, SNR was higher for time-resolved MRA compared with contrast-enhanced MRA in group C. CONCLUSIONS Low-dose time-resolved MRA is feasible in the evaluation of supra-aortic stenosis and could be used as an alternative to contrast-enhanced MRA for a diagnostic technique in high-risk populations.
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Seo K, Choi JW, Kim DW, Han D, Noh SJ, Jung HS. Aminophylline Effect on Renal Ischemia-Reperfusion Injury in Mice. Transplant Proc 2017; 49:358-365. [PMID: 28219599 DOI: 10.1016/j.transproceed.2016.11.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 10/01/2016] [Accepted: 11/16/2016] [Indexed: 01/25/2023]
Abstract
BACKGROUND Aminophylline increases the intracellular concentration of cAMP and exerts an anti-inflammatory effect. The aim of this study was to investigate the effect of aminophylline on renal ischemia-reperfusion (I/R) injury in mice. METHODS Thirty C57BL/6 mice were divided into 3 groups. In the sham group (group S, n = 10), only right nephrectomy was performed. In the control group (group C, n = 10), after right nephrectomy, the mice were subjected to 30 minutes of left renal ischemia. In the aminophylline group (group A, n = 10), an intraperitoneal injection of aminophylline (5 mg/kg) was performed before renal ischemia. Twenty-four hours after reperfusion, the mice were euthanized, and plasma and kidney samples were obtained to analyze the serum creatinine, renal histology, and expression levels of nuclear factor-kappa B (NF-kB) and pro-inflammatory cytokines. RESULTS The serum creatinine concentration in group C was markedly elevated at 24 hours after reperfusion. Aminophylline treatment significantly reduced serum creatinine, compared with group C. Aminophylline also reduced the histological evidence of renal damage. The expression levels of NF-kB, tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-2 (MIP-2), and intercellular adhesion molecule-1 (ICAM-1) mRNA were significantly increased in group C (P < .001). Group A showed lower expression of NF-kB, TNF-α, MCP-1, MIP-2, and ICAM-1 mRNA than group C (P < .01). CONCLUSIONS Aminophylline treatment improved the renal function and indexes of renal inflammation, which suggests that it provided reno-protection against renal I/R injury.
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Choi JW, Lee D, Hyun SH, Han M, Kim JH, Lee SJ. Intratumoural heterogeneity measured using FDG PET and MRI is associated with tumour-stroma ratio and clinical outcome in head and neck squamous cell carcinoma. Clin Radiol 2017; 72:482-489. [PMID: 28285707 DOI: 10.1016/j.crad.2017.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/02/2017] [Accepted: 01/31/2017] [Indexed: 11/28/2022]
Abstract
AIM To evaluate the association between the tumour-stroma ratio and intratumoural heterogeneity measured using 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) and magnetic resonance imaging (MRI), and further investigate the prognostic significance of imaging biomarkers in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS Textural-based imaging parameters of the primary tumour were extracted in 44 patients. In addition, the difference between the minimum and maximum apparent diffusion coefficient (ADC) values (ADCdiff) was calculated on MRI. The relationships between the tumour-stroma ratio and imaging parameters were evaluated. The associations between imaging parameters and recurrence-free survival (RFS) were assessed using Cox proportional hazard regression models. RESULTS Coarseness (r=-0.382) on PET and ADCdiff (r=0.534) on MRI were significantly correlated with the proportion of stroma. The best imaging biomarkers for the 2-year RFS prediction were coarseness (AUC=0.741) and ADCdiff (AUC=0.779). Multivariate analysis showed that coarseness (hazard ratio=10.549, 95% confidence interval=2.544-43.748, p=0.001) was an independent prognostic factor for RFS. CONCLUSION Heterogeneity imaging parameters are significantly associated with the tumour-stroma ratio. These imaging biomarkers may help to facilitate the risk stratification for tumour recurrence in HNSCC.
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Kim SS, Han GS, Kim GN, Koo DS, Kim IG, Choi JW. Advanced remediation of uranium-contaminated soil. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 164:239-244. [PMID: 27522327 DOI: 10.1016/j.jenvrad.2016.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 06/06/2023]
Abstract
The existing decontamination method using electrokinetic equipment after acidic washing for uranium-contaminated soil requires a long decontamination time and a significant amount of electric power. However, after soil washing, with a sulfuric acid solution and an oxidant at 65 °C, the removal of the muddy solution using a 100 mesh sieve can decrease the radioactivity of the remaining coarse soil to the clearance level. Therefore, only a small amount of fine soil collected from the muddy solution requires the electrokinetic process for its decontamination. Furthermore, it is found that the selective removal of uranium from the sulfuric washing solution is not obtained using an anion exchanger but rather using a cation exchanger, unexpectedly. More than 90% of the uranium in the soil washing solutions is adsorbed on the S-950 resin, and 87% of the uranium adsorbed on S-950 is desorbed by washing with a 0.5 M Na2CO3 solution at 60 °C.
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Kim KH, Tandi TE, Choi JW, Moon JM, Kim MS. Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak in South Korea, 2015: epidemiology, characteristics and public health implications. J Hosp Infect 2016; 95:207-213. [PMID: 28153558 PMCID: PMC7114867 DOI: 10.1016/j.jhin.2016.10.008] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 10/07/2016] [Indexed: 12/31/2022]
Abstract
Background Since the first case of Middle East respiratory syndrome coronavirus (MERS-CoV) in South Korea was reported on 20th May 2015, there have been 186 confirmed cases, 38 deaths and 16,752 suspected cases. Previously published research on South Korea's MERS outbreak was limited to the early stages, when few data were available. Now that the outbreak has ended, albeit unofficially, a more comprehensive review is appropriate. Methods Data were obtained through the MERS portal by the Ministry for Health and Welfare (MOHW) and Korea Centres for Disease Control and Prevention, press releases by MOHW, and reports by the MERS Policy Committee of the Korean Medical Association. Cases were analysed for general characteristics, exposure source, timeline and infection generation. Sex, age and underlying diseases were analysed for the 38 deaths. Findings Beginning with the index case that infected 28 others, an in-depth analysis was conducted. The average age was 55 years, which was a little higher than the global average of 50 years. As in most other countries, more men than women were affected. The case fatality rate was 19.9%, which was lower than the global rate of 38.7% and the rate in Saudi Arabia (36.5%). In total, 184 patients were infected nosocomially and there were no community-acquired infections. The main underlying diseases were respiratory diseases, cancer and hypertension. The main contributors to the outbreak were late diagnosis, quarantine failure of ‘super spreaders’, familial care-giving and visiting, non-disclosure by patients, poor communication by the South Korean Government, inadequate hospital infection management, and ‘doctor shopping’. The outbreak was entirely nosocomial, and was largely attributable to infection management and policy failures, rather than biomedical factors.
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Choi JW, Lyu AR, Ryu KA, Kim D, Park YH. Detection of pneumolabyrinth after temporal bone trauma using computed tomography. Acta Otolaryngol 2016; 136:682-6. [PMID: 27007704 DOI: 10.3109/00016489.2016.1157266] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSION Pneumolabyrinth is a very rare condition, even in otic capsule disrupting (OCD) fracture. Hearing was not always impaired, even in cases with OCD fracture. The co-existence of pneumocochlea, regarded as a risk factor for total hearing loss, was extremely rare in cases of pneumolabyrinth. OBJECTIVES The purposes of this study were to analyze the radiological and clinical features in patients with pneumolabyrinth and to overcome the diagnostic pitfalls encountered during pneumocochlea detection. MATERIALS AND METHODS The temporal bone computed tomographies (TBCT) of 402 patients diagnosed with temporal bone fracture along with their clinical records were retrospectively reviewed. RESULTS Only six patients (7% of those with OCD fractures or 1.5% of those with temporal bone fracture) were found to have pneumolabyrinth. Locations of the pneumolabyrinth were in the vestibule in all six cases and three of them showed air densities both in the cochlea and semicircular canal. The size of the air density in the vestibule was 5.38 ± 4.56 mm(2) at the axial view and 6.57 ± 5.67 mm(2) at the coronal view. The mean minimal Hounsfield unit (HU) of air density area in the vestibule was -968.1 ± 22.94 at the axial view and -941 ± 16.88 at the coronal view. Patients with pneumocochlea eventually developed total hearing loss.
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Kim YW, Hong JM, Park DG, Choi JW, Kang DH, Kim YS, Zaidat OO, Demchuk AM, Hwang YH, Lee JS. Effect of Intracranial Atherosclerotic Disease on Endovascular Treatment for Patients with Acute Vertebrobasilar Occlusion. AJNR Am J Neuroradiol 2016; 37:2072-2078. [PMID: 27313131 DOI: 10.3174/ajnr.a4844] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 04/24/2016] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND PURPOSE Although intracranial atherosclerotic disease is often encountered during endovascular treatment for acute vertebrobasilar occlusions, its clinical implication is not well-known. We aimed to evaluate whether intracranial atherosclerotic disease influences the clinical outcomes following endovascular treatment of acute vertebrobasilar occlusive stroke. MATERIALS AND METHODS Fifty-one patients with acute vertebrobasilar occlusive stroke were included. The onset-to-groin puncture time was ≤12 hours, and aspiration- or stent-based thrombectomy was used as the primary treatment method. Following primary endovascular treatment, intracranial atherosclerotic disease (IAD group) was angiographically diagnosed when a fixed focal stenosis was observed at the occlusion site, whereas embolism (embolic group) was diagnosed if no stenosis was observed. Clinical and treatment variables were compared in both groups, and IAD was evaluated as a prognostic factor for clinical outcomes. RESULTS The baseline NIHSS score tended to be lower (14 versus 22, P = .097) in the IAD group (n = 19) than in the embolic group (n = 32). The procedural time was longer in the IAD group (96 versus 61 minutes, P = .002), despite similar rates of TICI 2b-3 (89.5% versus 87.5%, P = 1.000). The NIHSS score at 7 days was higher (21 versus 8, P = .060) and poor outcomes (mRS 4-6 at 3 months) were more frequent in the IAD group (73.7% versus 43.8%, P = .038). IAD (odds ratio, 5.469; 95% CI, 1.09-27.58; P = .040) was independently associated with poor outcomes. CONCLUSIONS An arterial occlusion related to IAD was associated with a longer procedural time and poorer clinical outcome. Further studies are warranted to elucidate the appropriate endovascular strategy.
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