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Arthroscopically-Assisted Reduction and Internal Fixation of Intra-Articular Fractures of the Lateral Tibial Plateau (관절면을 침범한 경골 외측 고평부 골절에 대한 관절경을 이용한 정복 및 내고정술)

  • Kim, Juhan;Kim, Dong Hwi;Lim, Jae-Hwan;Jang, Hyunwoong;Kim, Young Wook
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.3
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    • pp.227-236
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    • 2019
  • Purpose: To evaluate the results of tibial lateral plateau fractures using arthroscopic-assisted reduction and internal fixation without cortical window or bone grafts. Materials and Methods: From March 2009 to March 2017, 27 patients with Schatzker type II tibial plateau fractures with articular depression and displacement over 5 mm on a computed tomography (CT) scan, who were treated with arthroscopic reduction and internal fixation and followed-up for at least 18 months, were enrolled in this study. Under arthroscopic guidance, the depressed fracture fragment was reduced using a freer and fixed with 5.0 or 6.5 mm cannulated screws through the inframeniscal portal without a cortical window or bone graft. The clinical and radiological results were evaluated using a Rasmussen system. Second look arthroscopy was performed in thirteen patients during the implant removal operation. Results: All fractures healed completely with a mean union time of 8.7 weeks (range from 8 to 12 weeks). Twenty four patients had good to excellent clinical results and 25 patients had good to excellent radiological results according to the Rasmussen classification. A well-healed articular surface with fibrocartilage was also found in 13 cases with second look arthroscopy. The 8 cases on CT scan at outpatient department follow-up showed bone union without bone grafting. Conclusion: Arthroscopic-assisted fixation of tibial lateral plateau fractures is a useful method without a cortical window or bone graft that produces good clinical results.

Effect of storage condition of resin cement on shear bond strength of the orthodontic bracket (레진시멘트의 보관 조건이 치열교정용 브라켓의 전단접착강도에 미치는 영향)

  • Seul-Gi, Yi;Jin-Woo, Kim;Se-Hee, Park;Yoon, Lee;Eung-Hyun, Kim;Kyung-Mo, Cho
    • Journal of Dental Rehabilitation and Applied Science
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    • v.38 no.4
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    • pp.189-195
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    • 2022
  • Purpose: For orthodontic bracket bonding, light curing resin cement is widely used because the process is convenient, and it can be polymerized at the desired time. This study compared the difference of bonding strength of orthodontic resin cement according to storage condition. Materials and Methods: After acid etching the bovine enamel surface with 37% phosphoric acid, 15 orthodontic brackets for mandible incisors were bonded with Ortho Connect and Orthomite LC according to following three conditions; 1) Immediate after 4℃ refrigeration for 3 months (IR), 2) One day room temperature after 4℃ refrigeration for 3 months (OR), 3) Room temperature for 3 months (RT). The shear bond strength was measured with a universal material tester and failure pattern of the specimen was observed. Two-way ANOVA and One-way ANOVA were used at the 95% significance level. Results: Ortho Connect that was applied immediately after refrigeration showed the maximum shear bond strength. Orthomite that was applied immediately after refrigeration showed the lowest shear bond strength, and the group stored at room temperature for three months showed the highest shear bond strength, and the difference between the two groups was significant. Conclusion: Ortho Connect can be used without worrying about bond strength even if it is used immediately after refrigeration, but Orthomite should be kept at room temperature sufficiently after refrigeration.

Effect of various surface treatment methods of highly translucent zirconia on the shear bond strength with resin cement (고투명도 지르코니아의 다양한 표면처리 방법이 레진시멘트와의 전단결합강도에 미치는 영향)

  • Yu-Seong Kim;Jin-Woo Choi;Hee-Kyung Kim
    • The Journal of Korean Academy of Prosthodontics
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    • v.61 no.3
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    • pp.179-188
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    • 2023
  • Purpose. The purpose of this study was to evaluate the effect of surface treatments on the shear bond strength of two types of zirconia (3-TZP and 5Y-PSZ) with resin cement. Materials and methods. Two different types of zirconia specimens with a fully sintered size of 14.0×14.0×2.0 mm3 were prepared, polished with 400, 600, and 800 grit silicon carbide paper, and buried in epoxy resin. They were classified into four groups each control, sandblasting, primer, and sandblasting & primer. Cylindrical resin adhered to the surface-treated zirconia with resin cement. It was stored in distilled water (37℃) for 24 hours, and a shear bond strength test was performed. The normality of the experimental group was confirmed with the Kolmogorov-Smirnov & Shapiro-Wilk test. The interaction and statistical difference were analyzed using a two-way ANOVA. A post-hoc analysis was performed using Dunnett T3. Results. As a result of two-way ANOVA, there was no significant difference in shear bonding strength between zirconia types (P > .05), but there was a significant correlation in the sandblasting, primer, and alumina sandblasting & primer group (P < .05). Dunnett T3 post-test showed that, regardless of the type of zirconia, shear bonding strength was sandblasting & primer > Primer > sandblasting > control group (P < .05). Conclusion. There was no difference in shear bond strength between the types of zirconia. The highest shear bond strength was shown when the mechanical and chemical treatments of the zirconia surface was performed simultaneously.

Functional Components and Antioxidant Activities of Perilla Leaf Genetic Resource (잎들깨 유전자원의 기능성분 및 항산화 활성)

  • Yeon Ju An;Jung In Kim;Sang Woo Kim;Sungup Kim;Eunyoung Oh;Jeongeun Lee;Eunsoo Lee;Eunae Yoo;Jung-Sook Sung;Myoung Hee Lee;Choon-Song Kim;Min Young Kim
    • The Korean Journal of Food And Nutrition
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    • v.36 no.5
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    • pp.379-386
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    • 2023
  • The objective of this study was to investigate the distribution of functional compounds in perilla leaves of various genetic resources and their antioxidant activities. A comprehensive analysis of functional compounds was conducted for 90 genetic resources, focusing on total polyphenol content (TPC), total flavonoid content (TFC), individual phenolic content (IPC), and lutein. Their antioxidant activities were then analyzed based on their radical scavenging capacity using ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl). The TPC content exhibited a range of 13.19 to 35.85 mg gallic acid equivalent/g, whereas the TFC content varied from 11.74 to 46.51 mg catechin equivalent/g. Total IPC was detected in a range of 6,310.98 to 40,491.82 ㎍/g. Lutein was detected at levels between 70.97 and 597.97 ㎍/g. ABTS and DPPH radical scavenging activities of perilla leaves ranged from 30.39 to 58.58 mg trolox equivalent (TE)/g and from 7.74 to 46.56 mg TE/g, respectively. Furthermore, correlation analysis demonstrated that rosmarinic acid, a phenolic acid, exhibited a significantly positive correlation with antioxidant activity. These findings suggest that various genetic resource of perilla leaves could effectively mediate antioxidant capacity. Results of this study provide valuable information for use of perilla leaves in Korea as functional food materials.

Usefulness assessment of the Volumetric Modulated Arc Therapy technique for reducing low-dose areas during radiotherapy for patients with multiple metastatic cancers (다발성 전이암 환자의 방사선치료 시 저선량 영역 감소를 위한 용적조절 회전 방사선치료(Volumetric Modulated Arc Therapy) 기법의 유용성 평가)

  • Yun-won Choi;Dong-min Jeong;Se-young Kim;Ryeong-hwang Park;I-ji Kim;Yong-wan Cho;Yongjae Kwon;Byeol-nim Park;Gyeong-min Yoo;Ho-kyung Moon;Dong-jae Jang;Jae-young Lee;Dayoung Lim;Sang-gyu Lee;Jong-geol Baek
    • The Journal of Korean Society for Radiation Therapy
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    • v.35
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    • pp.23-31
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    • 2023
  • Purpose: The purpose of this study is to evaluate the usefulness of Non-Treat Functionality Volumetric Modulated Arc Therapy(NTF-VMAT) and Treat Functionality VMAT(TF-VMAT) treatment plans in reducing the low-dose area during radiation therapy for patients with multiple metastatic cancers. Materials and Methods: The study was conducted on an Arccheck phantom, treatment planning target locations were set in pairs at intervals of 2 cm, 4 cm, and 6 cm on the X, Y, and Z axes. Based on these location settings, the volume of the low-dose area in NTF-VMAT and TF-VMAT was measured and compared. Results: The results of the study showed that, within a prescription dose range of 10% ~ 70%, the difference in low-dose area volumes across each axis was as follows: On the X-axis, there was a maximum difference of -47.6% and a minimum difference of -2.2%. On the Y-axis, there was a maximum difference of -17.5% and a minimum difference of -7.3%. The Z-axis showed a maximum difference of -39.7%, with the smallest difference being -6.8%. Conclusion: In radiation therapy for patients with multiple metastatic cancers, the TF-VMAT treatment plan was able to reduce the low-dose area by 10-40% compared to NTF-VMAT. This suggests that utilizing Treat Functionality, which includes the Island block technique, improves dose distribution and minimizes side effects, making it beneficial for the treatment of patients with multiple metastatic cancers.

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The synthesis of dextran from rice hydrolysates using Gluconobacter oxydans KACC 19357 bioconversion (Gluconobacter oxydans 생물전환을 통한 쌀 가수분해물 유래 dextran 합성)

  • Seung-Min Baek;Hyun Ji Lee;Legesse Shiferaw Chewaka;Chan Soon Park;Bo-Ram Park
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.149-160
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    • 2024
  • Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (1H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

Patterns in the Use and Perception of Digital Breast Tomosynthesis: A Survey of Korean Breast Radiologists (디지털 유방 토모신테시스에 대한 국내 사용 현황과 인식에 관한 설문조사 연구)

  • Eun Young Chae;Joo Hee Cha;Hee Jung Shin;Woo Jung Choi;Jihye Kim;Sun Mi Kim;Hak Hee Kim
    • Journal of the Korean Society of Radiology
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    • v.83 no.6
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    • pp.1327-1341
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    • 2022
  • Purpose To evaluate the pattern of use and the perception of digital breast tomosynthesis (DBT) among Korean breast radiologists. Materials and Methods From March 22 to 29, 2021, an online survey comprising 27 questions was sent to members of the Korean Society of Breast Imaging. Questions related to practice characteristics, utilization and perception of DBT, and research interests. Results were analyzed based on factors using logistic regression. Results Overall, 120 of 257 members responded to the survey (response rate, 46.7%), 67 (55.8%) of whom reported using DBT. The overall satisfaction with DBT was 3.31 (1-5 scale). The most-cited DBT advantages were decreased recall rate (55.8%), increased lesion conspicuity (48.3%), and increased cancer detection (45.8%). The most-cited DBT disadvantages were extra cost for patients (46.7%), insufficient calcification characterization (43.3%), insufficient improvement in diagnostic performance (39.2%), and radiation dose (35.8%). Radiologists reported increased storage requirements and interpretation time for barriers to implementing DBT. Conclusion Further improvement of DBT techniques reflecting feedback from the user's perspective will help increase the acceptance of DBT in Korea.

Response Prediction after Neoadjuvant Chemotherapy for Colon Cancer Using CT Tumor Regression Grade: A Preliminary Study (대장암 환자의 수술 전 항암화학요법의 반응을 CT 종양퇴행등급을 이용한 반응 예측: 예비 연구)

  • Hwan Ju Je;Seung Hyun Cho;Hyun Seok Oh;An Na Seo;Byung Geon Park;So Mi Lee;See Hyung Kim;Gab Chul Kim;Hunkyu Ryeom;Gyu-Seog Choi
    • Journal of the Korean Society of Radiology
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    • v.84 no.5
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    • pp.1094-1109
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    • 2023
  • Purpose To investigate whether CT-based tumor regression grade (ctTRG) can be used to predict the response to neoadjuvant chemotherapy (NAC) in colon cancer. Materials and Methods A total of 53 patients were enrolled. Two radiologists independently assessed the ctTRG using the length, thickness, layer pattern, and luminal and extraluminal appearance of the tumor. Changes in tumor volume were also analyzed using the 3D Slicer software. We evaluated the association between pathologic TRG (pTRG) and ctTRG. Patients with Rödel's TRG of 2, 3, or 4 were classified as responders. In terms of predicting responder and pathologic complete remission (pCR), receiver operating characteristic was compared between ctTRG and tumor volume change. Results There was a moderate correlation between ctTRG and pTRG (ρ = -0.540, p < 0.001), and the interobserver agreement was substantial (weighted κ = 0.672). In the prediction of responder, there was no significant difference between ctTRG and volumetry (Az = 0.749, criterion: ctTRG ≤ 3 for ctTRG, Az = 0.794, criterion: ≤ -27.1% for volume, p = 0.53). Moreover, there was no significant difference between the two methods in predicting pCR (p = 0.447). Conclusion ctTRG might predict the response to NAC in colon cancer. The diagnostic performance of ctTRG was comparable to that of CT volumetry.

Tumor Margin Infiltration in Soft Tissue Sarcomas: Prediction Using 3T MRI Texture Analysis (연조직 육종의 종양 가장자리 침윤: 3T 자기공명영상 텍스처 분석을 통한 예측)

  • Minji Kim;Won-Hee Jee;Youngjun Lee;Ji Hyun Hong;Chan Kwon Jung;Yang-Guk Chung;So-Yeon Lee
    • Journal of the Korean Society of Radiology
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    • v.83 no.1
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    • pp.112-126
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    • 2022
  • Purpose To determine the value of 3 Tesla (T) MRI texture analysis for predicting tumor margin infiltration in soft tissue sarcomas. Materials and Methods Thirty-one patients who underwent 3T MRI and had a pathologically confirmed diagnosis of soft tissue sarcoma were included in this study. Margin infiltration on pathology was used as the gold standard. Texture analysis of soft tissue sarcomas was performed on axial T1-weighted images (WI) and T2WI, fat-suppressed contrast-enhanced (CE) T1WI, diffusion-weighted images (DWI) with b-value of 800 s/mm2, and apparent diffusion coefficient (ADC) was mapped. Quantitative parameters were compared between sarcomas with infiltrative margins and those with circumscribed margins. Results Among the 31 patients with soft tissue sarcomas, 23 showed tumor margin infiltration on pathology. There were significant differences in kurtosis with the spatial scaling factor (SSF) of 0 and 6 on T1WI, kurtosis (SSF, 0) on CE-T1WI, skewness (SSF, 0) on DWI, and skewness (SSF, 2, 4) on ADC between sarcomas with infiltrative margins and those with circumscribed margins (p ≤ 0.046). The area under the receiver operating characteristic curve based on MR texture features for identification of infiltrative tumor margins was 0.951 (p < 0.001). Conclusion MR texture analysis is reliable and accurate for the prediction of infiltrative margins of soft tissue sarcomas.

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.