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A Study of the Capsuloligamentous Anatomy of the Glenohumeral Joint Using Magnetic Resonance Imaging and Three-Dimensional Imaging. Dynamic In Vivo Study (자기공명 영상 및 3차원 영상을 이용한 견관절 관절낭-인대의 해부학적 연구. 역동학적 생체연구)

  • Park Tae-Soo;Choi Il-Yong;Joo Kyung-Bin;Kim Sun-Il;Kim Jun-Sic;Paik Doo-Jin
    • Journal of the Korean Arthroscopy Society
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    • v.4 no.2
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    • pp.154-158
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    • 2000
  • Purpose : The purpose of this study is to demonstrate changes in the orientation ortho glenohumeral ligaments(GHL) in different degrees of abduction and rotation of the normal healthy individuals. Materials and Methods : Saline Magnetic Resonance(MR) arthrography of nine consecutive shoulders of normal healthy adults were checked. At that time, MR images were obtained in three different positions of abduction and external rotation($0^{\circ}C\;and\;0^{\circ},\;45^{\circ}C\;and\;25^{\circ}C,\;90^{\circ}$ and maximum, respectively). From a series of consecutive MRI, three-dimensional images were reconstructed after detecting the location of the middle glenohumeral ligament(MGHL) and the inferior glenohumeral ligament(IGHL) using workstation computer. Results : The shape of the MGHL was taken in double curved, and straight, and finally curved again in three different positions of the shoulder in sequence. On the other hand, the shape of the IGHL was obliquely positioned, and curvilinear, and finally straight and extended at lower part of the anterior surface of the humeral head. Conclusions : At $45^{\circ}$ of abduction and $25^{\circ}$ of external rotation, and at $90^{\circ}$ of abduction and maximal external rotation of the shoulder, the MGHL and the IGHL had the role of the most important static stabilizer of the glenohumeral joint repectively.

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Adaptive Image Rescaling for Weakly Contrast-Enhanced Lesions in Dedicated Breast CT: A Phantom Study (약하게 조영증강된 병변의 유방 전용 CT 영상의 대조도 개선을 위한 적응적 영상 재조정 방법: 팬텀 연구)

  • Bitbyeol Kim;Ho Kyung Kim;Jinsung Kim;Yongkan Ki;Ji Hyeon Joo;Hosang Jeon;Dahl Park;Wontaek Kim;Jiho Nam;Dong Hyeon Kim
    • Journal of the Korean Society of Radiology
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    • v.82 no.6
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    • pp.1477-1492
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    • 2021
  • Purpose Dedicated breast CT is an emerging volumetric X-ray imaging modality for diagnosis that does not require any painful breast compression. To improve the detection rate of weakly enhanced lesions, an adaptive image rescaling (AIR) technique was proposed. Materials and Methods Two disks containing five identical holes and five holes of different diameters were scanned using 60/100 kVp to obtain single-energy CT (SECT), dual-energy CT (DECT), and AIR images. A piece of pork was also scanned as a subclinical trial. The image quality was evaluated using image contrast and contrast-to-noise ratio (CNR). The difference of imaging performances was confirmed using student's t test. Results Total mean image contrast of AIR (0.70) reached 74.5% of that of DECT (0.94) and was higher than that of SECT (0.22) by 318.2%. Total mean CNR of AIR (5.08) was 35.5% of that of SECT (14.30) and was higher than that of DECT (2.28) by 222.8%. A similar trend was observed in the subclinical study. Conclusion The results demonstrated superior image contrast of AIR over SECT, and its higher overall image quality compared to DECT with half the exposure. Therefore, AIR seems to have the potential to improve the detectability of lesions with dedicated breast CT.

Semi-Quantitative Scoring of Late Gadolinium Enhancement of the Left Ventricle in Patients with Ischemic Cardiomyopathy: Improving Interobserver Reliability and Agreement Using Consensus Guidance from the Asian Society of Cardiovascular Imaging-Practical Tutorial (ASCI-PT) 2020

  • Cherry Kim;Chul Hwan Park;Do Yeon Kim;Jaehyung Cha;Bae Young Lee;Chan Ho Park;Eun-Ju Kang;Hyun Jung Koo;Kakuya Kitagawa;Min Jae Cha;Rungroj Krittayaphong;Sang Il Choi;Sanjaya Viswamitra;Sung Min Ko;Sung Mok Kim;Sung Ho Hwang;Nguyen Ngoc Trang;Whal Lee;Young Jin Kim;Jongmin Lee;Dong Hyun Yang
    • Korean Journal of Radiology
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    • v.23 no.3
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    • pp.298-307
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    • 2022
  • Objective: This study aimed to evaluate the effect of implementing the consensus statement from the Asian Society of Cardiovascular Imaging-Practical Tutorial 2020 (ASCI-PT 2020) on the reliability of cardiac MR with late gadolinium enhancement (CMR-LGE) myocardial viability scoring between observers in the context of ischemic cardiomyopathy. Materials and Methods: A total of 17 cardiovascular imaging experts from five different countries evaluated CMR obtained in 26 patients (male:female, 23:3; median age [interquartile range], 55.5 years [50-61.8]) with ischemic cardiomyopathy. For LGE scoring, based on the 17 segments, the extent of LGE in each segment was graded using a five-point scoring system ranging from 0 to 4 before and after exposure according to the consensus statement. All scoring was performed via web-based review. Scores for slices, vascular territories, and total scores were obtained as the sum of the relevant segmental scores. Interobserver reliability for segment scores was assessed using Fleiss' kappa, while the intraclass correlation coefficient (ICC) was used for slice score, vascular territory score, and total score. Inter-observer agreement was assessed using the limits of agreement from the mean (LoA). Results: Interobserver reliability (Fleiss' kappa) in each segment ranged 0.242-0.662 before the consensus and increased to 0.301-0.774 after the consensus. The interobserver reliability (ICC) for each slice, each vascular territory, and total score increased after the consensus (slice, 0.728-0.805 and 0.849-0.884; vascular territory, 0.756-0.902 and 0.852-0.941; total score, 0.847 and 0.913, before and after implementing the consensus statement, respectively. Interobserver agreement in scoring also improved with the implementation of the consensus for all slices, vascular territories, and total score. The LoA for the total score narrowed from ± 10.36 points to ± 7.12 points. Conclusion: The interobserver reliability and agreement for CMR-LGE scoring for ischemic cardiomyopathy improved when following guidance from the ASCI-PT 2020 consensus statement.

Development of Rabbit Brain Tumor Model Using VX2 Cells and Verification with the MRI in Neuroradiologic Research (Neuroradiology 연구를 위한 VX2 세포를 이용한 토끼 뇌종양 모델 제작과 MRI를 이용한 검증)

  • Yong-Woo Kim;Seon Hee Choi;Hak Jin Kim
    • Journal of the Korean Society of Radiology
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    • v.84 no.2
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    • pp.441-453
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    • 2023
  • Purpose To evaluate the development, location, and volume of a VX2 carcinoma using four inoculation methods in a rabbit brain. Materials and Methods Inoculation of a VX2 cell suspension was performed 1) on the appointed day, 2) seven days after storing a VX2 carcinoma in a freezer or 3) seven days after storing a VX2 carcinoma in a deep freezer after sacrificing the donor rabbits. 4) Without sacrificing the rabbits, the VX2 cell suspension was obtained using a gun biopsy, inoculation was performed on the appointed day. MR imaging was performed 10 days after inoculation. Brain tissues were obtained the day after. The development, location, and volume of the tumor were evaluated. Results Seventeen of the 18 rabbits inoculated on the appointed day developed tumors (average tumor volume, 106.32 mm3). One of five inoculated seven days after storing the VX2 tumor in the freezer, and three of five inoculated seven days after storing the VX2 tumor in the deep freezer developed tumors. Inoculation with a VX2 cell suspension obtained with a gun biopsy from five rabbits revealed development of tumors in only two rabbits. The tumors mostly developed in the superficial cortex. Conclusion TVX2 rabbit brain tumor model is easy to develop and revealed variable reproducibility. This model can be applicable in radiologic imaging, treatment planning, interventional treatment and drug delivery research. VX2 cell can be successfully innoculated into the brain using variable methods under researcher's variable conditions.

Limitation of Nitrogen ion Implantation and Ionplating Techniques Applied for Improvement of Wear Resistance of Metallic Implant Materials (금속 임플란트 소재의 내마모성 향상을 위하여 적용되는 질소 이온주입 및 이온도금법의 한계)

  • 김철생
    • Journal of Biomedical Engineering Research
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    • v.25 no.2
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    • pp.157-163
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    • 2004
  • Nitrogen ion implantation and ion plating techniques were applied for improvement of the wear resistance of metallic implant materials. In this work, the wear dissolution behaviour of a nitrogen ion implanted super stainless steel (S.S.S, 22Cr-20Ni-6Mo-0.25N) was compared with those of S.S.S, 316L SS and TiN coated 316L SS. The amounts of Cr and Ni ions worn-out from the specimens were Investigated using an electrothermal atomic absorption spectrometry. Furthermore, the Ti(Grade 2) disks were coated with TiN, ZrN and TiCN by use of low temperature arc vapor deposition and the wear resistance of the coating layers was compared with that of titanium. The chemical compositions of the nitrogen ion implanted and nitride coated layers were examined with a scanting auger electron spectroscopy. It wat observed that the metal ions released from the nitrogen ion implanted S.S.S surface were significantly reduced. From the results obtained, it was shown that the nitrogen ion implanted zone obtained with 100 KeV ion energy was easily removed within 200,000 revolutions from a wear dissolution testing under a similar load condition when applied to artificial hip joint. The remarkable improvement in wear resistance weir confirmed by the nitrides coated Ti materials and the wear properties differ greatly according to the chemical composition of the coating layers. for specimens with the same coating thickness of about 3$\mu\textrm{m}$, TiCN coated Ti showed the highest wear resistance. However, after removing the coating layers, the wear rates of all nitrides coated Ti reverted to their normal rates of below 10,000 revolutions from Ti-disk-on-disk wear testing under the same load condition. From the results obtained, it is suggested that the insufficient depth of the 100 Kel N$\^$+/ ion implanted zone and of the nitrides coated layers of 3$\mu\textrm{m}$ are subject to restriction when used as frictional parts of load bearing implants.

An Updated Meta-analysis on the Association of X-Ray Repair Cross Complementing Group 1 Codon 399 Polymorphism with Hepatocellular Carcinoma Risk

  • Wang, Ya-Dong;Zhai, Wen-Long;Wang, Hai-Yu;Xia, Xiang-Qun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4443-4448
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    • 2014
  • Background: A number of studies have reported the association of X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism with susceptibility to hepatocellular carcinoma (HCC). However, the results were inconsistent and inconclusive. The aim of this study was to comprehensively explore the association of XRCC1 Arg399Gln variant with HCC risk. Materials and Methods: Systematic searches of PubMed, Elsevier, Science Direct, CNKI and Chinese Biomedical Literature Database were performed. Pooled odds ratio (OR) with 95% confidence intervals (CI) was calculated to estimate the strength of association. Results: Overall, we observed an increased HCC risk among subjects carrying XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln genotypes (OR=1.20, 95%CI: 1.05-1.38, OR=1.16, 95%CI: 1.05-1.28, and OR=1.14, 95%CI: 1.04-1.24, respectively) based on 20 studies including 3374 cases and 4633 controls. In subgroup analysis, we observed an increased risk of XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln polymorphisms for HCC in hospital-based study (OR=1.25, 95%CI: 1.03-1.51, OR=1.21, 95%CI: 1.07-1.36 and OR=1.18, 95%CI: 1.06-1.31, respectively) and in Asian population (OR=1.19, 95%CI: 1.03-1.38, OR=1.17, 95%CI: 1.04-1.30 and OR=1.14, 95%CI: 1.04-1.25, respectively). Limiting the analysis to the studies with controls in agreement with Hardy-Weinberg equilibrium (HWE), we observed an increased HCC risk among Gln/Gln, Arg/Gln and Gln/ Gln+Arg/Gln genotype carriers (OR=1.17, 95%CI: 1.05-1.29, OR=1.12, 95%CI: 1.00-1.25 and OR=1.11, 95%CI: 1.02-1.21, respectively). Conclusions: This updated meta-analysis results suggest that XRCC1 Arg399Gln variants may contribute to HCC risk. Well-designed studies with larger sample size were required to further verify our findings.

Clinical and genetic characteristics of Korean patients with IARS2-related disorders

  • Lee, Jin Sook;Kim, Man Jin;Kim, Soo Yeon;Lim, Byung Chan;Kim, Ki Joong;Choi, Murim;Seong, Moon-Woo;Chae, Jong-Hee
    • Journal of Genetic Medicine
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    • v.16 no.2
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    • pp.55-61
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    • 2019
  • Purpose: Genetic defects in the nuclear-encoded mitochondrial aminoacyl-tRNA synthetases were first identified as causes of various disorders in 2007. Variants in IARS2, which encodes a mitochondrial isoleucyl-tRNA synthetase, were first reported in 2014. These variants are associated with diverse phenotypes ranging from CAGSSS (CAtaracts, Growth hormone deficiency, Sensory neuropathy, Sensorineural hearing loss, and Skeletal dysplasia) and Leigh syndrome to isolated nonsyndromic cataracts. Here, we describe the phenotypic and genetic spectrum of Korean patients with IARS2-related disorders. Materials and Methods: Using whole-exome sequencing followed by Sanger sequencing, we identified five patients with IARS2 mutations. Their medical records and brain magnetic resonance images were reviewed retrospectively. Results: All five patients presented with developmental delay or regression before 18 months of age. Three patients had bilateral cataracts, but none had hearing loss or sensory neuropathy. No evidence of skeletal dysplasia was noted, but two had short stature. One patient had cardiomyopathy and another exhibited renal tubulopathy and hypoparathyroidism. Their brain imaging findings were consistent with Leigh syndrome. Interestingly, we found the recurrent mutations p.R817H and p.V105Dfs*7 in IARS2. Conclusion: To our knowledge, this is the first report of Korean patients with IARS2-related disorders. Our findings broaden the phenotypic and genotypic spectrum of IARS2-related disorders in Korea and will help to increase clinical awareness of IARS2-related neurodegenerative diseases.

Evaluation of osteogenic activity of periosteal-derived cells treated with inflammatory cytokines (골막기원세포의 조골세포로의 분화과정에서 염증성 사이토카인의 효과)

  • Park, Bong-Wook;Choi, Mun-Jeoung;Hah, Young-Sool;Cho, Hee-Young;Kim, Deok-Ryong;Kim, Uk-Kyu;Kang, Hee-Jea;Kim, Jong-Ryoul;Byun, June-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.36 no.5
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    • pp.341-345
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    • 2010
  • Introduction: Skeletal homeostasis is normally maintained by the stability between bone formation by osteoblasts and bone resorption by osteoclasts. However, the correlation between the inflammatory reaction and osteoblastic differentiation of cultured osteoprogenitor cells has not been fully investigated. This study examined the effects of inflammatory cytokines on the osteoblastic differentiation of cultured human periosteal-derived cells. Materials and Methods: Periosteal-derived cells were obtained from the mandibular periosteum and introduced into the cell culture. After passage 3, the periosteal-derived cells were further cultured in an osteogenic induction Dulbecco's modified Eagle's medium (DMEM) medium containing dexamethasone, ascorbic acid, and $\beta$-glycerophosphate. In this culture medium, tumor necrosis factor (TNF)-$\alpha$ with different concentrations (0.1, 1, and 10 ng/mL) or interleukin (IL)-$1{\beta}$ with different concentrations (0.01, 0.1, and 1 ng/mL) were added. Results: Both TNF-$\alpha$ and IL-$1{\beta}$ stimulated alkaline phosphatase (ALP) expression in the periosteal-derived cells. TNF-$\alpha$ and IL-$1{\beta}$ increased the level of ALP expression in a dose-dependent manner. Both TNF-$\alpha$ and IL-$1{\beta}$ also increased the level of alizarin red S staining in a dose-dependent manner during osteoblastic differentiation of cultured human periosteal-derived cells. Conclusion: These results suggest that inflammatory cytokines TNF-$\alpha$ and IL-$1{\beta}$ can stimulate the osteoblastic activity of cultured human periosteal-derived cells.

Parents Response for the Therapy Support Services Provided by Center for Special Education - Centered on Parents of Occupational Therapy Support Service - (특수교육지원센터 치료지원서비스에 대한 견해 - 작업치료 서비스를 받는 보호자를 중심으로 -)

  • Song, Min-Ok;Lee, Sung-Ja;Kim, Hun-Ju
    • The Journal of Korean Academy of Sensory Integration
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    • v.8 no.1
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    • pp.51-60
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    • 2010
  • Objective : The purpose of this study is to provide practical guidelines for the better performance of the Occupational therapy services(OT services) in the Supporting Center for Special Education. The study is based upon the quality and satisfaction of the OT services, measured by interviewing parents whose children have taken the services provided by Ulsan Kang-Nam Supporting Center for Special Education. Methods : Five parents for the children having OT services since March, 2010 in the Kang-Nam Supporting Center were interviewed individually. The interview per each person took thirty to fifty minutes and was all audio-recorded. Results : The satisfaction of the qualification for the OT therapists working at the Kang-Nam Supporting Center was high. The quality for treatment facilities and the variety for treatment materials met the expectation for OT to be well-performed. The free OT treatment system was the one of significant features for the OT services provided by the Kang-Nam Supporting Center. However, the perception of the interviewed parents for the OT was very low.

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Electromyographic Activity of the Biceps Brachii Muscle in Shoulders With Anterior Instability (전방 불안정성 견관절에서 이두박근의 근전도 활동성)

  • Kim Seung-Ho;Ha Kwon-Ick;Kim Hyeon-Sook;Kim Seon-Woo;Park Jong Hyuk;Kim Young-Min
    • Clinics in Shoulder and Elbow
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    • v.3 no.2
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    • pp.87-94
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    • 2000
  • Purpose : The purpose of this study was to evaluate the activity of the biceps brachii muscle in the vulnerable abduction and external rotation position of the shoulder in patients with anterior instability. Materials and Methods: This experimental study include a prospective analysis of the electromyographic(EMG) data on a group of patients with traumatic unilateral anterior instability of the shoulder. The EMG data of unstable shoulders was compared with those of opposite shoulders as control. The optimal sample size for the case-control study was calculated using an nQuery Advisor program(nQuery Adviser 3.0, Statisticl solutions Ltd., Ireland). The EMG analyses were conducted in 76 shoulders in 38 patients who had a traumatic anterior instability in one shoulder. The EMG records were obtained at different position of shoulder, which included 0° , 45° , 90° and 120° of shoulder abduction. In each angle of shoulder abduction, the arms were placed in an external rotation as tolerated by the anterior apprehension. The paired-sample T test was used to compare the difference of the root mean square(RMS) voltages between the stable and unstable shoulders in each degree of arm position. Results : The RMS voltage of the biceps muscle was significantly greater in the unstable shoulder than opposite stable shoulder in all position of the arm(p<0.001). The RMS voltage of the biceps was maximal at 90° and 120° of external rotation in the unstable shoulder(p<0.05). The RMS voltage of the supraspinatus muscle revealed no differences in any of the test conditions(p=0.904, 0.506, 0.119 and 0.781 in 0° , 45° , 90° and 120° , respectively) Conclusion: In the vulnerable abduction and external rotation position, the biceps muscle plays an active compensatory role in the unstable shoulder while not in the stable shoulder.

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