98 results on '"Tae Gyu Kim"'
Search Results
2. CDKN2A Homozygous Deletion Is a Stronger Predictor of Outcome than IDH1/2-Mutation in CNS WHO Grade 4 Gliomas
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Sang Hyuk Lee, Tae Gyu Kim, Kyeong Hwa Ryu, Seok Hyun Kim, and Young Zoon Kim
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glioma ,CDKN2A deletion ,IDH mutation ,glioblastoma ,astrocytoma ,prognosis ,Biology (General) ,QH301-705.5 - Abstract
Background: We primarily investigated the prognostic role of CDKN2A homozygous deletion in CNS WHO grade 4 gliomas. Additionally, we plan to examine traditional prognostic factors for grade 4 gliomas and validate the findings. Materials: We conducted a retrospective analysis of the glioma cohorts at our institute. We reviewed medical records spanning a 15-year period and examined pathological slides for an updated diagnosis according to the 2021 WHO classification of CNS tumors. We examined the IDH1/2 mutation and CDKN2A deletion using NGS analysis with ONCOaccuPanel®. Further, we examined traditional prognostic factors, including age, WHO performance status, extent of resection, and MGMT promoter methylation status. Results: The mean follow-up duration was 27.5 months (range: 4.1–43.5 months) and mean overall survival (OS) was 20.7 months (SD, ±1.759). After the exclusion of six patients with a poor status of pathologic samples, a total of 136 glioblastoma cases diagnosed by previous WHO classification criteria were newly classified into 29 (21.3%) astrocytoma, IDH-mutant, and CNS WHO grade 4 cases, and 107 (78.7%) glioblastoma, IDH-wildtype, and CNS WHO grade 4 cases. Among them, 61 (56.0%) had CDKN2A deletions. The high-risk group with CDKN2A deletion regardless of IDH1/2 mutation had a mean OS of 16.65 months (SD, ±1.554), the intermediate-risk group without CDKN2A deletion and with IDH1/2 mutation had a mean OS of 21.85 months (SD, ±2.082), and the low-risk group without CDKN2A deletion and with IDH1/2 mutation had a mean OS of 33.38 months (SD, ±2.946). Multifactor analysis showed that age (≥50 years vs. MGMT promoter methylation, (methylated vs. unmethylated; HR 5.078), IDH1/2 mutation (mutant vs. wildtype; HR 6.352), and CDKN2A deletion (absence vs. presence; HR 13.454) were associated with OS independently. Conclusions: The present study suggests that CDKN2A deletion plays a powerful prognostic role in CNS WHO grade 4 gliomas. Even if CNS WHO grade 4 gliomas have mutant IDH1/2, they may have poor clinical outcomes because of CDKN2A deletion.
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- 2024
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3. Corrigendum to ‘Assessment of deep learning-based auto-contouring on interobserver consistency in target volume and organs-at-risk delineation for breast cancer: Implications for RTQA program in a multi-institutional study’ [The Breast 73 (2024) 103599]
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Min Seo Choi, Jee Suk Chang, Kyubo Kim, Jin Hee Kim, Tae Hyung Kim, Sungmin Kim, Hyejung Cha, Oyeon Cho, Jin Hwa Choi, Myungsoo Kim, Juree Kim, Tae Gyu Kim, Seung-Gu Yeo, Ah Ram Chang, Sung-Ja Ahn, Jinhyun Choi, Ki Mun Kang, Jeanny Kwon, Taeryool Koo, Mi Young Kim, Seo Hee Choi, Bae Kwon Jeong, Bum-Sup Jang, In Young Jo, Hyebin Lee, Nalee Kim, Hae Jin Park, Jung Ho Im, Sea-Won Lee, Yeona Cho, Sun Young Lee, Ji Hyun Chang, Jaehee Chun, Eung Man Lee, Jin Sung Kim, Kyung Hwan Shin, and Yong Bae Kim
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Published
- 2024
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4. Impact of high dose radiotherapy for breast tumor in locoregionally uncontrolled stage IV breast cancer: a need for a risk-stratified approach
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Nalee Kim, Haeyoung Kim, Won Park, Won Kyung Cho, Tae Gyu Kim, Young-Hyuck Im, Jin Seok Ahn, Yeon Hee Park, and Ji-Yeon Kim
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Metastatic breast cancer ,Palliative ,Radiation therapy ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Aim Patients with locoregionally uncontrolled breast tumors are frequently referred for breast palliative radiotherapy (PRT) to mitigate symptoms. We analyzed the outcomes following breast PRT to optimize PRT according to risk groups. Methods We reviewed 133 patients who underwent breast PRT. A median total dose of 45 Gy was prescribed with an equivalent dose in 2 Gy fractions (EQD2, α/β = 3.5) of 53 Gy. The Cox proportional hazards model was used to analyze the prognostic factors of local control (LC). Results Most (90.2%) had polymetastatic disease (> 5 lesions), and 48.9% had bone metastasis. With a median follow-up of 17.2 months, the 2-year LC and overall survival (OS) rates were 49.4%, and 48.3%, respectively. Multivariable analyses demonstrated progressive or mixed responses outside the breast and > 2 lines of previous therapy as adverse features for clinical outcomes. Group 1 (0 risk factors) showed favorable 2-year LC and OS of 63.9%, and 72.8%, respectively, whereas group 3 (2 risk factors) showed the worst outcomes of 0%, and 6.8%, respectively. Breast PRT with EQD2 ≥ 63 Gy showed a significant benefit in LC for group 1 and marginal benefit (p = 0.055) for group 2, but no improvement for group 3 (p = 0.300). Conclusion Breast PRT showed favorable LC outcomes in patients with stable disease outside the breast and treated with ≤ 2 lines of systemic treatment. Our findings warrant future clinical trials investigating the role of higher than palliative dose and early intervention of PRT in stage IV patients.
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- 2023
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5. Effect of high-dose radiation therapy on positive margins after breast-conserving surgery for invasive breast cancer
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Hyunjung Kim, Tae Gyu Kim, Byungdo Park, Jeong Ho Kim, Si-Youl Jun, Jun Ho Lee, Hee Jun Choi, Chang Shin Jung, Yoon Ju Bang, Hyoun Wook Lee, Jae Seok Lee, Hyun Yeol Nam, Seunghyeon Shin, Sung Min Kim, and Haeyoung Kim
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Age ,Breast cancer ,Local recurrence ,Radiation therapy ,Resection margin ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Purpose: Positive margins after breast-conserving surgery are associated with poor oncological outcomes and warrant additional surgery. This study aimed to evaluate the effectiveness of high-dose radiation therapy for positive margins by comparing local recurrence between patients with positive and negative margins. Methods: We retrospectively evaluated 550 patients treated with adjuvant radiation therapy after breast-conserving surgery for invasive breast cancer between 2013 and 2019. The total equivalent dose in 2 Gy fractions (EQD2) to the tumor bed ranged from 65.81 to 66.25 Gy for positive margins and 59.31–61.81 Gy for negative margins. The differences in local recurrence between the positive and negative margin groups were analyzed. Results: After a median follow-up of 58 months, the crude local recurrence rate was 7.3% in the positive margin group (n = 55) and 2.4% in the negative margin group (n = 495). Positive margins were associated with higher local recurrence without statistical significance in the entire cohort (p = 0.062). Among patients aged
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- 2023
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6. Assessment of deep learning-based auto-contouring on interobserver consistency in target volume and organs-at-risk delineation for breast cancer: Implications for RTQA program in a multi-institutional study
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Min Seo Choi, Jee Suk Chang, Kyubo Kim, Jin Hee Kim, Tae Hyung Kim, Sungmin Kim, Hyejung Cha, Oyeon Cho, Jin Hwa Choi, Myungsoo Kim, Juree Kim, Tae Gyu Kim, Seung-Gu Yeo, Ah Ram Chang, Sung-Ja Ahn, Jinhyun Choi, Ki Mun Kang, Jeanny Kwon, Taeryool Koo, Mi Young Kim, Seo Hee Choi, Bae Kwon Jeong, Bum-Sup Jang, In Young Jo, Hyebin Lee, Nalee Kim, Hae Jin Park, Jung Ho Im, Sea-Won Lee, Yeona Cho, Sun Young Lee, Ji Hyun Chang, Jaehee Chun, Eung Man Lee, Jin Sung Kim, Kyung Hwan Shin, and Yong Bae Kim
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RTQA ,Inter-observer variation ,Auto-contouring ,Breast cancer ,Deep learning ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Purpose: To quantify interobserver variation (IOV) in target volume and organs-at-risk (OAR) contouring across 31 institutions in breast cancer cases and to explore the clinical utility of deep learning (DL)-based auto-contouring in reducing potential IOV. Methods and materials: In phase 1, two breast cancer cases were randomly selected and distributed to multiple institutions for contouring six clinical target volumes (CTVs) and eight OAR. In Phase 2, auto-contour sets were generated using a previously published DL Breast segmentation model and were made available for all participants. The difference in IOV of submitted contours in phases 1 and 2 was investigated quantitatively using the Dice similarity coefficient (DSC) and Hausdorff distance (HD). The qualitative analysis involved using contour heat maps to visualize the extent and location of these variations and the required modification. Results: Over 800 pairwise comparisons were analysed for each structure in each case. Quantitative phase 2 metrics showed significant improvement in the mean DSC (from 0.69 to 0.77) and HD (from 34.9 to 17.9 mm). Quantitative analysis showed increased interobserver agreement in phase 2, specifically for CTV structures (5–19 %), leading to fewer manual adjustments. Underlying IOV differences causes were reported using a questionnaire and hierarchical clustering analysis based on the volume of CTVs. Conclusion: DL-based auto-contours improved the contour agreement for OARs and CTVs significantly, both qualitatively and quantitatively, suggesting its potential role in minimizing radiation therapy protocol deviation.
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- 2024
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7. Benefit of postoperative regional nodal irradiation in patients receiving preoperative systemic therapy with docetaxel/carboplatin/trastuzumab/pertuzumab for HER2-positive breast cancer
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Nalee Kim, Ji-Yeon Kim, Won Park, Won Kyung Cho, Tae Gyu Kim, Young-Hyuck Im, Jin Seok Ahn, Jeong Eon Lee, Seok Jin Nam, Seok Won Kim, Jonghan Yu, Byung Joo Chae, Sei Kyung Lee, Jai-Min Ryu, Yeon Hee Park, and Haeyoung Kim
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Radiation therapy ,HER2-positive breast cancer ,Neoadjuvant ,Anti-HER2 targeted therapy ,Primary systemic therapy ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Aim: The role of regional nodal irradiation (RNI) after preoperative systemic treatment (PST) with targeted therapy for HER2-positive breast cancer remains uncertain. This study aimed to investigate the impact of RNI on locoregional recurrence (LRR) and disease-free survival (DFS) outcomes after docetaxel/carboplatin/trastuzumab/pertuzumab (TCHP) for PST. Methods: We retrospectively analyzed 255 patients who were treated with six cycles of TCHP between 2016 and 2019. The patients were divided into four groups based on clinical nodal involvement: group A, with no nodal disease; group B, with axillary lymph node (AXL) level I; group C, with AXL level I with II/III; and group D, with supraclavicular or internal mammary nodes. Results: The RNI group had more advanced nodal disease (C/D) than the no RNI group (56.9 % vs. 6.8 %). With a median follow-up of 51.3 months, there were two (0.8 %), three (1.2 %), and 15 (5.9 %) local, regional, and distant metastases, respectively. LRR did not differ significantly according to the RNI (2.6 % vs. 1.0 %, p = 0.651). Group D had the most frequent distant metastases (17.5 %; p = 0.005). The 4-year DFS rate was 92.7 %, and DFS did not improve significantly after RNI (p = 0.074). When stratified by clinical nodal groups and pathological axillary response, RNI had no effect on LRR/DFS outcomes. Conclusion: With a rare incidence of LRR, RNI did not significantly affect LRR or DFS in patients with HER2-positive breast cancer after with PST-TCHP. However, intensive systemic treatment is required for advanced diseases (C/D). Selective de-intensified RNI and intensified systemic treatment should be investigated in future studies.
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- 2023
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8. Increasing buffering capacity enhances rumen fermentation characteristics and alters rumen microbiota composition of high-concentrate fed Hanwoo steers
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Sonny C. Ramos, Seon Ho Kim, Chang Dae Jeong, Lovelia L. Mamuad, A-Rang Son, Seung Ha Kang, Yong Il Cho, Tae Gyu Kim, Jin Sung Lee, Kwang Keun Cho, Sung Sill Lee, and Sang Suk Lee
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Medicine ,Science - Abstract
Abstract The buffering capacity of buffer agents and their effects on in vitro and in vivo rumen fermentation characteristics, and bacterial composition of a high-concentrate fed Hanwoo steers were investigated in this study. Treatments were comprised of CON (no buffer added), BC0.3% (low buffering capacity, 0.3% buffer), BC0.5% (medium buffering capacity, 0.5% buffer), and BC0.9% (high buffering capacity, 0.9% buffer). Four Hanwoo steers in a 4 × 4 Latin square design were used for the in vivo trial to assess the effect of treatments. Results on in vitro experiment showed that buffering capacity, pH, and ammonia–nitrogen concentration (NH3-N) were significantly higher in BC0.9% and BC0.5% than the other treatments after 24 h incubation. Individual and total volatile fatty acids (VFA) concentration of CON were lowest compared to treatment groups. Meanwhile, in vivo experiment revealed that Bacteroidetes were dominant for all treatments followed by Firmicutes and Proteobacteria. The abundances of Barnesiella intestinihominis, Treponema porcinum, and Vibrio marisflavi were relatively highest under BC0.9%, Ruminoccocus bromii and Succiniclasticum ruminis under BC0.5%, and Bacteroides massiliensis under BC0.3%. The normalized data of relative abundance of observed OTUs’ representative families have grouped the CON with BC0.3% in the same cluster, whereas BC0.5% and BC0.9% were clustered separately which indicates the effect of varying buffering capacity of buffer agents. Principal coordinate analysis (PCoA) on unweighted UniFrac distances revealed close similarity of bacterial community structures within and between treatments and control, in which BC0.9% and BC0.3% groups showed dispersed community distribution. Overall, increasing the buffering capacity by supplementation of BC0.5% and and BC0.9% buffer agents enhanced rumen fermentation characteristics and altered the rumen bacterial community, which could help prevent ruminal acidosis during a high-concentrate diet.
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- 2022
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9. Role of adjuvant chemoradiotherapy and chemotherapy in patients with resected gallbladder carcinoma: a multi-institutional analysis (KROG 19-04)
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Sung Uk Lee, Jinsil Seong, Tae Hyun Kim, Jung Ho Im, Woo Chul Kim, Kyubo Kim, Hae Jin Park, Tae Gyu Kim, Youngkyong Kim, Bae Kwon Jeong, Jin Hee Kim, Byoung Hyuck Kim, and Taek-Keun Nam
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gallbladder cancer ,adjuvant treatment ,chemoradiotherapy ,locoregional recurrence-free survival ,overall survival ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Objective: The effectiveness of adjuvant treatments for resected gallbladder carcinoma (GBC) has remained unclear due to lack of randomized controlled trials; thus, the aim of present study was to evaluate the role of adjuvant treatments, including chemoradiotherapy (CRT) and/or chemotherapy (CTx), in patients with resected GBC. Methods: A total of 733 GBC patients who received curative-intent surgical resection were identified in a multi-institutional database. Of 733 patients, 372 (50.8%) did not receive adjuvant treatment, whereas 215 (29.3%) and 146 (19.9%) received adjuvant CTx and CRT, respectively. The locoregional recurrence-free survival (LRFS), recurrence-free survival (RFS), and overall survival (OS) of the adjuvant treatment groups were compared according to tumor stage (stage II vs. stage III–IV). Results: In stage II disease (n = 381), the 5-year LRFS, RFS, and OS were not significantly different among the no-adjuvant therapy, CTx, and CRT groups, and positive resection margin, presence of perineural invasion, and Nx classification were consistently associated with worse LRFS, RFS, and OS in the multivariate analysis (P < 0.05). For stage III–IV (n = 352), the CRT group had significantly higher 5-year LRFS, RFS, and OS than the no-adjuvant therapy and CTx groups (67.8%, 45.2%, and 56.9%; 37.9%, 28.8%, and 35.4%; and 45.0%, 30.0%, and 45.7%, respectively) (P < 0.05). Conclusions: CRT has value as adjuvant treatment for resected GBC with stage III–IV disease. Further study is needed for stage II disease with high-risk features.
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- 2022
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10. Patient-related risk factors for late rectal bleeding after hypofractionated radiotherapy for localized prostate cancer: a single-center retrospective study
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Tae Gyu Kim, Byungdo Park, Yun Gyu Song, Hyoun Wook Lee, Tae Hee Oh, Dong-Soo Ryu, Seung Chan Jeong, Daehyeon Cho, Jieun Oh, Kwang Min Kim, Jung Won Lee, Hyoun Soo Lee, Sung Min Kong, Jun Young Kim, and Haeyoung Kim
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Prostate cancer ,Proctitis ,Radiation dose hypofractionation ,Anticoagulants ,Liver cirrhosis ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Several studies have reported patient-related risk factors for late rectal bleeding following conventionally fractionated radiotherapy for prostate cancer. We investigated patient-related risk factors for late rectal bleeding after hypofractionated radiotherapy. Methods A total of 231 patients with local or locally advanced prostate cancer treated with hypofractionated radiotherapy (70 or 67.2 Gy in 28 fractions) were evaluated retrospectively. All patients received intensity-modulated radiotherapy with daily image guidance. The relationships between late rectal bleeding and risk factors like diabetes, hypertension, cirrhosis, and anticoagulant use were analyzed. Results During a median follow-up of 23 months, the crude rates of grade ≥ 1, grade ≥ 2, and grade ≥ 3 late rectal bleeding were 23.8%, 16.9%, and 9.5%, respectively. Cirrhosis and anticoagulant use predicted an increased risk of grade ≥ 3 rectal bleeding in multivariable analyses (hazard ratio [HR] 14.37, 95% confidence interval [CI] 3.09–66.87, P = 0.001, and HR 2.93, 95% CI 1.14–7.55, P = 0.026, respectively). The non-anticoagulant group had a significantly superior 5-year freedom from grade ≥ 3 bleeding compared to the anticoagulant group in a propensity-weighted log-rank analysis (88.0% vs. 76.7%, P = 0.041). A receiver operating characteristic curve analysis revealed that rectal bleeding was minimized in the anticoagulant group if the equivalent dose at fractionation of 2 Gy (EQD2) V77 Gy of the rectum was
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- 2022
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11. Clinical Outcomes of RTOG 9310 Protocol for Primary Central Nervous System Lymphoma: Single-Center Experience with 87 Patients
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Jinuk Kim, Tae Gyu Kim, Hyoun Wook Lee, Seok Hyun Kim, Ji Eun Park, Moonok Lee, and Young Zoon Kim
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adverse effect ,chemotherapy ,methotrexate ,primary CNS lymphoma ,prognosis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
The Radiation Therapy Oncology Group (RTOG) 9310 protocol clinical trial established high-dose methotrexate (HDMTX) as the standard for primary central nervous system lymphoma (PCNSL). We aimed to investigate the RTOG 9310 protocol’s PCNSL outcomes by examining progression-free survival (PFS) and overall survival (OS) rates and determining the influential factors. Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL and treated with the RTOG 9310 protocol. All received HDMTX 2.5 g/m2 and vincristine 1.4 mg/m2/day for 1 day during weeks 1, 3, 5, 7, and 9, and procarbazine 100 mg/m2/day for 1 day during weeks 1, 5, and 9. Dexamethasone was administered on a standard tapering schedule from the first week to the sixth week. Whole brain radiotherapy (WBRT), consisting of 45 Gy for patients with less than a complete response to the chemotherapy or 36 Gy for complete responders, was started 1 week after the last dose of chemotherapy was administered. Within three weeks of the completion of WBRT, patients received two courses of cytarabine, which were separated by 3–4 weeks. Clinical, radiological, and histopathological characteristics were retrospectively reviewed. All patients completed five HDMTX cycles and a mean follow-up of 60.2 (range, 6–150) months. Twenty-eight (32.2%) patients experienced recurrence during follow-up. The mean time to recurrence was 21.8 months, while the mean PFS was 104.3 (95% confidence interval (CI), 90.6–118.0) months. Eleven (12.6%) patients died; the mean OS was 132.1 (95% CI, 122.2–141.9) months. The 3- and 5-year survival rates were 92.0% and 87.4%, respectively. One patient experienced acute renal failure, while the remainder tolerated any cytotoxic side effects. On multivariate analysis, the Eastern Cooperative Oncology Group performance score ≤ 2; the International Extranodal Lymphoma Study Group low-risk status; XBP-1, p53, and c-Myc negativity; homogenous enhancement; gross total resection, independently correlated with long PFS and OS. The RTOG 9310 protocol is effective for PCNSL and features good outcomes.
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- 2021
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12. Video‐assisted thoracoscopic surgical wedge resection using multiplanar computed tomography reconstruction‐fluoroscopy after CT guided microcoil localization
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Moon Ok Lee, Sung Yup Jin, Sang Kyung Lee, Sangwon Hwang, Tae Gyu Kim, and Yun Gyu Song
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computed tomography multiplanar reconstruction ,fluoroscopy ,pulmonary nodule ,video‐assisted thoracoscopic surgery ,wedge resection ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background When early‐stage lung cancer is diagnosed, the recommended treatment is anatomical resection using video‐assisted thoracoscopic surgery (VATS) or robotic lobectomy. However, nonanatomical resection, known as wedge resection (WR), which is performed to diagnose pulmonary nodules, can be problematic for clinicians performing VATS or robotic‐assisted thoracic surgery (RATS). The purpose of this study was to evaluate the safety and effectiveness of VATS WR using multiplanar computed tomography reconstruction (CT MPR)‐fluoroscopy after CT guided microcoil localization to achieve complete pulmonary nodule resection. Methods Between January 2016 to December 2020, the medical records of patients who underwent CT‐guided microcoil localization for suspicious malignant pulmonary nodules and VATS WR with CT MPR and intraoperative fluoroscopy were retrospectively reviewed. Results All 130 patients successfully underwent CT‐guided localization. The success rate of VATS WR with CT MPR‐intraoperative fluoroscopy was 98.5%. Mean operation time was 58 min (range 50–84 min). The postoperative complication rate was 3.1%, and no major postoperative complications were reported. The mean postoperative length of hospital stay was 4.7 days (range 4–8 days). Conclusions VATS WR using CT MPR‐fluoroscopy after CT guided microcoil localization is a safe and highly effective approach for complete pulmonary nodule resection. However, even in uniport VATS or recently performed robotic surgery, localization and resection of nonvisible, nonpalpable pulmonary nodules is a challenging problem. Consequently, satisfactory outcomes can be expected if this technique is used for suspicious malignant pulmonary nodule resection.
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- 2021
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13. Extranasopharyngeal Angiofibroma of the Nasal Septum: A Case Report
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Gyoung-Eun Lee, Tae Gyu Kim, Kyung-Eun Bae, Kyoung Rai Cho, Jung Heob Sohn, Bo Young Kim, Hyun-jung Kim, and Guhyun Kang
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angiofibroma ,nasal septum ,vascular neoplasm ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Angiofibroma is benign hypervascular tumor that usually occurs in the nasopharynx of adolescent male patient and rarely originates from outside of the nasopharynx, called extranasopharyngeal angiofibroma. The clinical and radiologic findings of extranasopharyngeal angiofibroma are similar to other hypervascular tumors, which may delay diagnosis and treatment. We present a case of extranasopharyngeal angiofibroma arising from nasal septum of a 43-yearold male who complained of right nasal obstruction. Contrast enhancement CT revealed a hypervascular tumor of the nasal septum and the tumor was removed by endoscopic resection. Histopathologic examination confirmed the diagnosis of angiofibroma.
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- 2019
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14. Mixed Adenoneuroendocrine Carcinoma of the Small Bowel in a Patient with Crohn’s Disease: A Case Report
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Kwang-Min Kim, Kyung Eun Bae, Jae Hyung Kim, Myeong Ja Jeong, Soung Hee Kim, Ji-Young Kim, Soo Hyun Kim, Jihae Lee, Mi-Jin Kang, and Tae Gyu Kim
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crohn disease ,intestinal neoplasms ,neuroendocrine tumors ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumor of the gastrointestinal tract that has both exocrine and neuroendocrine components. There are only 5 case reports about this combined tumor in the small bowel, arose in a background of long-standing Crohn’s disease. Here, we report a case of small bowel MANEC in a 54-year-old male with Crohn’s disease, who presented a heterogeneous enhancing, asymmetric small bowel wall thickening with small bowel obstruction and had a difficulty in differential diagnosis before surgery.
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- 2019
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15. Improved Thermal Resistance and Electrical Conductivity of a Boron-Doped DLC Film Using RF-PECVD
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Wanrong Li, Xing Yan Tan, Yeong Min Park, Dong Chul Shin, Dae Weon Kim, and Tae Gyu Kim
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DLC ,boron-doped ,RF-PECVD ,thermal treatment ,electrical resistance ,Technology - Abstract
Diamond-like carbon (DLC) film doped with boron has unique properties and displays higher thermal resistance, lower internal stress, and better electrical conductivity than un-doped DLC film; this makes it is suitable for various applications, especially in outer space. Radio-frequency plasma-enhanced chemical vacuum deposition of boron-doped DLC film was performed to determine the optimal percentage of boron for improving thermal resistance. Additional heat treatment and 40 vol% B2H6/CH4 yielded the best electrical conductivity. X-ray photoelectron spectroscopy, thermal gravimetric analysis, Raman spectroscopy, and the four-point probe method were utilized to analyze the properties of boron-doped DLC film. The boron-doped DLC film displayed outstanding performance in terms of thermal resistance and electrical conductivity.
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- 2020
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16. W-Band Modular Antenna/Detector Array for the Electron Cyclotron Emission Imaging System in KSTAR
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Gwan Hui Lee, Jung Seok Lee, Dong Hwi Kim, Syifa Haunan Nashuha, Mun Ju Kim, Byung Cheol Min, Jae Hyun Lee, Woo Chang Lee, Gun Su Yun, Tae Gyu Kim, Bong Tae Kim, Hyun Chul Choi, Hyeon Keo Park, Yong Kyoon In, and Kang Wook Kim
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modular antenna/detector array ,elliptical mini-lens ,dual-dipole antenna ,wideband antenna balun ,maintenance ,W-band ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A design of a modular antenna/detector array for the electron cyclotron emission (ECE) imaging system at the Korea Superconducting Tokamak Advanced Research (KSTAR) is proposed. The modular antenna/detector array is based on a unit antenna/detector module, which consists of an elliptical mini-lens, a dual-dipole antenna, an antenna balun, a low-noise amplifier, and a metal frame. The proposed modular antenna/detector array resolves the problem in the conventional antenna/detector array where one faulty channel requires the entire array to be removed for the service. With the proposed modular array, each channel module can be easily and independently removed and replaced without interference to the rest of the array, thus minimizing the interrupted service time for maintenance. Moreover, the unit channel modules can be efficiently updated under a variety of the tokamak operation conditions. The antenna/detector modules are optimized to have improved performance, and are tested in a W-band test setup, and consistently provide the gain increase by 10~20 dB as compared with the conventional antenna/detector array. A set of the proposed modular antenna/detector array is currently installed and tested in the KSTAR ECE imaging system, and will consistently produce the improved ECE imaging to monitor MHD instability activities under various plasma operation conditions.
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- 2022
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17. Breast Cavernous Hemangioma with Increased Size on Ultrasonography: A Case Report
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Kwang-Min Kim, Ji-Young Kim, Soung Hee Kim, Myeong Ja Jeong, Soo Hyun Kim, Jae Hyung Kim, Kyung Eun Bae, Ji Hae Lee, Mi-Jin Kang, and Tae Gyu Kim
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breast ,hemangioma ,ultrasonography ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Cavernous hemangioma of the breast is a rare benign vascular tumor. It is usually diagnosed as non-palpable mass during imaging examination, incidentally. Common sonographic finding of the breast hemangioma is a superficially located, oval shape, circumscribed margin mass. But the appearance of breast hemangioma is variable and it can be difficult to diagnose in preoperatively. Here, we report a 68-year-old female case with palpable breast mass and increased size on follow up ultrasonography.
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- 2018
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18. A Case of Granular Cell Tumor of the Breast in a Male Patient
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Gyoung-Eun Lee, Ji-Young Kim, Jae Hyung Kim, Myeong Ja Jeong, Soung Hee Kim, Soo Hyun Kim, Mi-Jin Kang, Ji Hae Lee, Kyung-Eun Bae, and Tae Gyu Kim
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granular cell tumor ,male breast tumor ,breast ultrasonography ,s-100 protein ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
A 52-year-old male complained of a painless, firm, and slow-growing mass in his right breast outer portion. The chest CT revealed a 3.3 cm-sized oval shaped, microlobulated, mild enhancing mass. Ultrasound showed a microlobulated marginated heterogeneous hypoechoic mass with internal vascularity and calcifications in the mass. On the ultrasound-guided core needle biopsy, the mass was confirmed as a benign granular cell tumor (GCT). The patient transferred to another hospital and underwent surgical removal of the lesion. GCT of the breast is uncommon and mostly benign neoplasm to originate from Schwann cell. Clinical and radiologic features of GCTs, including CT and ultrasound images, mimic malignancy and make diagnosis of GCT more difficult. The CT images of GCTs are much rarely reported. Physicians and radiologists must be aware of radiologic characteristics of this rare benign tumor for male breast, to avoid misdiagnosis this tumor for breast malignancy and overtreat.
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- 2018
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19. The Implications of X-ray Use in Chuna Manual Therapy from the Viewpoint of Korean Medicine Doctors
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Tae Gyu Kim, Yumi Gi, Kyu Jin Yang, Ki-Beom Lee, Hooin Jo, Jongho Choi, Yoon Jae Lee, Sanghun Lee, and In-Hyuk Ha
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Korean traditional medicine ,manual therapy ,survey ,X-ray ,Miscellaneous systems and treatments ,RZ409.7-999 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background The purpose of this survey study was to understand how utilization of X-rays as an adjunct to Chuna manual therapy (CT) supports treatment, as assessed by Korean medicine doctors (KMDs). Methods A survey was emailed to all 18,289 members of the Association of Korean Oriental Medicine (AKOM)to determine the implications of X-ray use in CT. Surveys were collected from September 22, 2017 to October 15, 2017. Results Of the 18,289 KMDs 562 completed the survey. The implications of a radiological diagnosis (X-ray) with CT was assessed using 5 items in a questionnaire: time to diagnosis, accuracy of treatment, patient comprehension and satisfaction, CT effect, and safety of CT. Survey participants identified improvement in patient comprehension and satisfaction as the most important factor for X-ray use with CT, followed by increased safety of CT. From the determinant factors for selection of CT intensity and specific techniques, severity of clinical symptoms was shown to be the most influential factor. Degenerative changes of the spine and degree of spinal malposition were also reported to be highly influential. Conclusions The KMDs’ that participated in this study indicated that utilization of X-rays in conjunction with CT administration improved patient comprehension and satisfaction, and CT safety. Installation of radiological equipment in Korean medicine clinics where CT is provided may increase safety and patients’ satisfaction.
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- 2018
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20. Isolated Myxoma in the External Auditory Canal: A Case Report
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Ah Reum Park, Tae Gyu Kim, Hyun-Jung Kim, Woo Ho Cho, Jae Hyung Kim, Myeong Ja Jeong, Soung Hee Kim, Ji-Young Kim, Soo Hyun Kim, Mi-Jin Kang, Ji Hae Lee, and Kyung Eun Bae
- Subjects
myxoma ,external auditory canal ,magnetic resonance imaging ,tomography ,x-ray computed ,carney complex ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Myxoma is a benign mesenchymal neoplasm found in the heart, bone, and other soft tissues. However, myxoma of the external auditory canal is extremely rare. Since myxoma of the external auditory canal can be manifested as a part of the Carney complex, an autosomal dominant multiple familial neoplastic disorder, correct diagnosis and thorough investigation is important. We report a case of a 59-year-old man who presented to hospital with a complaint of growing mass within the right external auditory canal during one month. The surgical excision was done, and the histopathological examination revealed myxoma. In this article, we report the magnetic resonance imaging and computed tomography findings of the myxoma of the external auditory canal and correlate with the histopathological finding.
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- 2018
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21. Retroperitoneal Extraskeletal Osteosarcoma without Calcification Mimicking Pancreas Tumor: CT Imaging of a Case Report
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Jung Won Kim, Kyung Eun Bae, Kyeong Mee Park, Jae Hyung Kim, Myeong Ja Jeong, Soung Hee Kim, Ji Young Kim, Soo Hyun Kim, Mi Jin Kang, Ji Hae Lee, and Tae Gyu Kim
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retroperitoneal space ,osteosarcoma ,ossification ,tomography ,x-ray computed ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Retroperitoneal extraskeletal osteosarcoma is a rare tumor. Typical imaging findings include a soft tissue mass accompanied with internal calcifications. The authors encountered a case involving a 44-year-old woman with a large retroperitoneal extraskeletal osteosarcoma, without calcification, that mimicked a pancreatic tumor. The present report highlights computed tomography features of retroperitoneal extraskeletal osteosarcoma, followed by a brief literature review. It is challenging for radiologists to diagnose retroperitoneal masses. However, in patients who present with large retroperitoneal masses, combined with clinical information including the elevation of serum alkaline phosphatase levels, retroperitoneal extraskeletal osteosarcoma should be considered in the differential diagnosis, even if the mass does not exhibit a gross calcification on the imaging.
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- 2018
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22. Patterns of failure after resection of extrahepatic bile duct cancer: implications for adjuvant radiotherapy indication and treatment volumes
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Hoon Sik Choi, Ki Mun Kang, Bae Kwon Jeong, Hojin Jeong, Yun Hee Lee, In Bong Ha, Tae Gyu Kim, and Jin Ho Song
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Bile duct neoplasms ,Recurrence ,Adjuvant radiotherapy ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background The role of adjuvant radiotherapy (RT) and setting proper RT target volumes have not been clearly demonstrated for extrahepatic bile duct (EHBD) cancer, due to the rarity of the disease and the lack of randomized trials. This study was conducted to evaluate the indication and treatment volume for adjuvant RT in EHBD cancer patients by identifying the prognostic factors for loco-regional (LR) failure, and analyze the patterns of LR failure. Methods Ninety-three patients with EHBD cancer, who underwent resection without adjuvant RT, at 2 medical centers, between 2001 and 2016, were analyzed retrospectively. Univariable and multivariable analyses were performed to find the prognostic factors for LR recurrence. The initial patterns of failure were recorded, especially those of LR recurrence, and categorized according to the Japanese classification. Results The median follow-up duration was 30 months, and 38 (40.9%) patients experienced LR recurrence during this period. With regards to LR recurrence, close or positive resection margin (RM) status (p
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- 2018
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23. Femoro-Supragenicular Popliteal Bypass with a Bridging Stent Graft in a Diffusely Diseased Distal Target Popliteal Artery: Alternative to Below-Knee Popliteal Polytetrafluoroethylene Bypass
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Joung Hun Byun, Tae Gyu Kim, and Yun Gyu Song
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Arteries ,Bypass ,Graft ,Stents ,Surgery ,RD1-811 - Abstract
Background: Lesions in distal target arteries hinder surgical bypass procedures in patients with peripheral arterial occlusive disease. Methods: Between April 2012 and October 2015, 16 patients (18 limbs) with lifestyle- limiting claudication (n=12) or chronic critical limb ischemia (n=6) underwent femoral–above-knee (AK) polytetrafluoroethylene (PTFE) bypass grafts with a bridging stent graft placement between the distal target popliteal artery and the PTFE graft. Ring-supported PTFE grafts were used in all patients with no available vein for graft material. Follow-up evaluations assessed clinical symptoms, the ankle-brachial index, ultrasonographic imaging and/or computed tomography angiography, the primary patency rate, and complications. Results: All procedures were successful. The mean follow-up was 12.6 months (range, 11 to 14 months), and there were no major complications. The median baseline ankle-brachial index of 0.4 (range, 0.2 to 0.55) significantly increased to 0.8 (range, 0.5 to 1.0) at 12 months (p<0.01). The primary patency rate at 12 months was 83.3%. The presenting symptoms resolved within 2 weeks. Conclusion: In AK bypasses with a diffusely diseased distal target popliteal artery or when below-knee (BK) bypass surgery is impossible, this procedure could be clinically effective and safe when used as an alternative to femoral-BK bypass surgery.
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- 2017
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24. Definitive Radiation Therapy for Early Glottic Cancer: Experience of Two Fractionation Schedules
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Tae Gyu Kim, Yong Chan Ahn, Hee Rim Nam, Man Ki Chung, Han-Sin Jeong, Young-Ik Son, and Chung-Hwan Baek
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Laryngeal neoplasms ,Radiotherapy ,Dose fractionation ,Medicine ,Otorhinolaryngology ,RF1-547 - Abstract
ObjectivesThe authors would report the results of definitive radiation therapy (RT) for early glottic cancer by two different radiation dose schedules.MethodsFrom February of 1995 till June of 2008, 157 patients with T1-2N0 glottic cancer were treated with curative RT at Samsung Medical Center. All patients had squamous cell carcinoma, and there were 89 patients (56.7%) with T1a, 36 (22.9%) with T1b, and 32 (20.4%) with T2. Two different radiation dose schedules were used: 70 Gy in 35 fractions to 64 patients (40.8%, group A); and 67.5 Gy in 30 fractions to 93 patients (59.2%, group B). The median treatment durations were 50 days (range, 44 to 59 days) and 44 days (range, 40 to 67 days) in the groups A and B, respectively.ResultsThe median follow-up durations were 85 and 45 months for the groups A and B. No severe late complication of RTOG grade 3 or higher was observed, and there was no difference in acute or chronic complication between the groups. Twenty-four patients experienced treatment failure: local recurrence only in 19 patients; regional recurrence only in one; combined local and regional recurrence in four; and systemic metastasis in none. The overall 5-year disease-free survival and disease-specific survival rates were 84.7% and 94.8%. The disease-free survival rate in the group B was better (78.3% vs. 90.8%, P=0.031). This difference was significant only in T1 stage (83.4% vs. 94.6%, P=0.025), but not in T2 (62.7% vs. 60.6%, P=0.965). Univariate analysis showed that the tumor extent, cord mobility, T-stage, and the dose schedule had significant influence on the disease-free survival, and multivariate analysis showed that only the tumor extent and the dose schedule were associated with the disease-free survival.ConclusionSuperior disease-free survival could be achieved by 2.25 Gy per fraction without increased toxicity over shorter RT duration, when compared with 2.0 Gy per fraction.
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- 2012
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25. Inverted V-shape Osteotomy with Central Strip Resection: A Simultaneous Narrowing and Vertical Reduction Genioplasty
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Tae Gyu Kim, MD, PhD, Jung Hun Lee, MD, PhD, and Young Kyoo Cho, MD, PhD
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Surgery ,RD1-811 - Abstract
Background: In East Asian countries, a prominent, long, and squared contour of the lower third of the face is considered unattractive, strong, and masculine. To change such a facial contour into an ovular contour, correction of the chin area is essential to accomplish the overall curve in the mandibuloplasty, and various methods for the horizontal reduction of the chin area have been suggested. The horizontal osteotomy and central strip resection technique, which is the most widely used method, has comparatively little effect and some restrictions. To improve these points, the authors introduced an effective method for simultaneously reducing the width and height of the chin without additional procedures. Methods: From March 2010 to May 2013, 432 women and 117 men underwent mandibular contouring surgery. Of these patients, 321 needed correction of the chin shape with simultaneous mandibular contouring surgery. Narrowing and vertical reduction genioplasty was performed for these patients using an inverted V-shaped osteotomy with central bony segment resection. Results: Narrowing and vertical reduction genioplasty was successfully performed in all cases. No severe complications were observed. Transient sensory changes of the skin around the chin were observed in 87 patients, but all recovered within 3 months. All of the patients were satisfied with the results. Conclusions: The method that we introduce in this article is a simple and more effective method for simultaneous reduction of the width and height of the chin without additional procedures. The square and long face was effectively and easily reshaped into a slender ovular contour, and the shape of the chin was changed from square to slender.
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- 2014
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26. Oncological outcomes in patients with residual triple-negative breast cancer after preoperative chemotherapy.
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Hyunki Park, Haeyoung Kim, Won Park, Won Kyung Cho, Nalee Kim, Tae Gyu Kim, Young-Hyuck Im, Jin Seok Ahn, Yeon Hee Park, Ji-Yeon Kim, Seok Jin Nam, Seok Won Kim, Jeong Eon Lee, Jonghan Yu, Byung Joo Chae, Sei Kyung Lee, and Jai-Min Ryu
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PATHOLOGIC complete response ,TRIPLE-negative breast cancer ,CANCER patients ,PROGNOSIS ,LUMPECTOMY - Abstract
Purpose: This study aimed to evaluate the clinical outcomes and prognostic implications of regional nodal irradiation (RNI) after neoadjuvant chemotherapy (NAC) in patients with residual triple-negative breast cancer (TNBC). Materials and Methods: We analyzed 152 patients with residual TNBC who underwent breast-conserving surgery after NAC between December 2008 and December 2017. Most patients (n = 133; 87.5%) received taxane-based chemotherapy. Adjuvant radiotherapy (RT) was administered at a total dose of 45-65 Gy in 15--30 fractions to the whole breast, with some patients also receiving RT to regional nodes. Survival was calculated using the Kaplan--Meier method, and prognostic factors influencing survival were analyzed using the Cox proportional-hazards model. Results: During a median follow-up of 66 months (range, 9 to 179 months), the 5-year disease-free survival (DFS) rate was 68.0%. The 5-year locoregional recurrence-free survival, distant metastasis- free survival, and overall survival rates were 83.6%, 72.6%, and 78.7%, respectively. In the univariate analysis, the cN stage, ypT stage, ypN stage, axillary operation type, and RT field were associated with DFS. Multivariate analysis revealed that higher ypT stage (hazard ratio [HR] = 2.0; 95% confidence interval [CI] 1.00-3.82; p = 0.049) and ypN stage (HR = 4.7; 95% CI 1.57-14.24; p = 0.006) were associated with inferior DFS. Among clinically node-positive patients, those who received RT to the breast only had a 5-year DFS of 73.7%, whereas those who received RNI achieved a DFS of 59.6% (p = 0.164). There were no differences between the DFS and RNI. Conclusion: In patients with residual TNBC, higher ypT and ypN stages were associated with poorer outcomes after NAC. RNI did not appear to improve DFS. More intensive treatments incorporating systemic therapy and RT should be considered for these patients. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Combined High-Dose Radiotherapy with Sequential Gemcitabine-Cisplatin Based Chemotherapy Increase the Resectability and Survival in Locally Advanced Unresectable Intrahepatic Cholangiocarcinoma: A Multi-institutional Cohort Study.
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Jung Ho Im, Jeong Il Yu, Tae Hyun Kim, Tae Gyu Kim, Jun Won Kim, and Jinsil Seong
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PROPORTIONAL hazards models ,OVERALL survival ,PROGNOSIS ,MULTIVARIATE analysis ,CHEMORADIOTHERAPY - Abstract
Purpose: The locally advanced unresectable intrahepatic cholangiocarcinoma (ICC) has detrimental oncological outcomes. In this study, we aimed to investigate the efficacy of radiotherapy in patients with locally advanced unresectable ICC. Materials and Methods: Between 2001 and 2021, 116 patients were identified through medical record who underwent radiotherapy for locally advanced unresectable ICC. The resectability of ICC is determined by the multidisciplinary team at each institution. Overall survival (OS) were analyzed using the Kaplan-Meier method, and prognostic factors were analyzed using the Cox proportional hazards model. Results: The median equivalent radiotherapy dose in 2 Gy fractions (EQD2) was 52 Gy (range, 30 to 110 Gy). Forty-seven patients (40.5%) received sequential gemcitabine-cisplatin based chemotherapy (GEM-CIS CTx). Multivariate analysis identified two risk factors, EQD2 of = 60 Gy and application of sequential GEM-CIS CTx for OS. Patients were grouped by these two risk factors: group 1, EQD2 = 60 Gy with sequential GEM-CIS CTx (n=25); group 2, EQD2 < 60 Gy with sequential GEM-CIS CTx or fluoropyrimidine-based concurrent chemoradiotherapy (n=70); and group 3, radiotherapy alone (n=21). Curative resection was more frequently undergone in group 1 than in groups 2 or 3 (28% vs. 8.6% vs. 0%, respectively). Consequently, OS was significantly better in group 1 than in groups 2 and 3 (p < 0.05). Conclusion Combined high-dose radiotherapy with sequential GEM-CIS CTx improved oncologic outcomes in patients with locally advanced unresectable ICC. Further prospective studies are required to validate these findings. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Risk Factors for Distant Metastasis in Extrahepatic Bile Duct Cancer after Curative Resection (KROG 1814).
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Younghee Park, Tae Hyun Kim, Kyubo Kim, Jeong Il Yu, Wonguen Jung, Jinsil Seong, Woo Chul Kim, Jin Hwa Choi, Ah Ram Chang, Bae Kwon Jeong, Byoung Hyuck Kim, Tae Gyu Kim, Jin Hee Kim, Hae Jin Park, Hyun Soo Shin, Jung Ho Im, and Eui Kyu Chie
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CHOLANGIOCARCINOMA ,DISEASE risk factors ,LYMPHATIC metastasis ,METASTASIS ,BIOMEDICAL materials - Abstract
Purpose Risk factors predicting distant metastasis (DM) in extrahepatic bile duct cancer (EHBDC) patients treated with curative resection were investigated. Materials and Methods Medical records of 1,418 EHBDC patients undergoing curative resection between Jan 2000 and Dec 2015 from 14 institutions were reviewed. After resection, 924 patients (67.6%) were surveilled without adjuvant therapy, 297 (21.7%) were treated with concurrent chemoradiotherapy (CCRT) and 148 (10.8%) with CCRT followed by chemotherapy. To exclude the treatment effect from innate confounders, patients not treated with adjuvant therapy were evaluated. Results After a median follow-up of 36.7 months (range, 2.7 to 213.2 months), the 5-year distant metastasis-free survival (DMFS) rate was 57.7%. On multivariate analysis, perihilar or diffuse tumor (hazard ratio [HR], 1.391; p=0.004), poorly differentiated histology (HR, 2.014; p < 0.001), presence of perineural invasion (HR, 1.768; p < 0.001), positive nodal metastasis (HR, 2.670; p < 0.001) and preoperative carbohydrate antigen (CA) 19-9 ≥ 37 U/mL (HR, 1.353; p < 0.001) were significantly associated with inferior DMFS. The DMFS rates significantly differed according to the number of these risk factors. For validation, patients who underwent adjuvant therapy were evaluated. In patients with ≥ 3 factors, additional chemotherapy after CCRT resulted in a superior DMFS compared with CCRT alone (5-year rate, 47.6% vs. 27.7%; p=0.001), but the benefit of additional chemotherapy was not observed in patients with 0-2 risk factors. Conclusion Tumor location, histologic differentiation, perineural invasion, lymph node metastasis, and preoperative CA 19-9 level predicted DM risk in resected EHBDC. These risk factors might help identifying a subset of patients who could benefit from additional chemotherapy after resection. [ABSTRACT FROM AUTHOR]
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- 2024
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29. Role of adjuvant chemoradiotherapy and chemotherapy in patients with resected gallbladder carcinoma: a multiinstitutional analysis (KROG 19-04).
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Sung Uk Lee, Jinsil Seong, Tae Hyun Kim, Jung Ho Im, Woo Chul Kim, Kyubo Kim, Hae Jin Park, Tae Gyu Kim, Youngkyong Kim, Bae Kwon Jeong, Jin Hee Kim, Byoung Hyuck Kim, and Taek-Keun Nam
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CHEMORADIOTHERAPY ,ADJUVANT chemotherapy ,GALLBLADDER ,RECTAL cancer ,OVERALL survival ,RANDOMIZED controlled trials ,TUMOR classification - Abstract
Objective: The effectiveness of adjuvant treatments for resected gallbladder carcinoma (GBC) has remained unclear due to lack of randomized controlled trials; thus, the aim of present study was to evaluate the role of adjuvant treatments, including chemoradiotherapy (CRT) and/or chemotherapy (CTx), in patients with resected GBC. Methods: A total of 733 GBC patients who received curative-intent surgical resection were identified in a multi-institutional database. Of 733 patients, 372 (50.8%) did not receive adjuvant treatment, whereas 215 (29.3%) and 146 (19.9%) received adjuvant CTx and CRT, respectively. The locoregional recurrence-free survival (LRFS), recurrence-free survival (RFS), and overall survival (OS) of the adjuvant treatment groups were compared according to tumor stage (stage II vs. stage III-IV). Results: In stage II disease (n = 381), the 5-year LRFS, RFS, and OS were not significantly different among the no-adjuvant therapy, CTx, and CRT groups, and positive resection margin, presence of perineural invasion, and Nx classification were consistently associated with worse LRFS, RFS, and OS in the multivariate analysis (P < 0.05). For stage III-IV (n = 352), the CRT group had significantly higher 5-year LRFS, RFS, and OS than the no-adjuvant therapy and CTx groups (67.8%, 45.2%, and 56.9%; 37.9%, 28.8%, and 35.4%; and 45.0%, 30.0%, and 45.7%, respectively) (P < 0.05). Conclusions: CRT has value as adjuvant treatment for resected GBC with stage III-IV disease. Further study is needed for stage II disease with high-risk features. [ABSTRACT FROM AUTHOR]
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- 2022
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30. A Deep Learning Model with High Standalone Performance for Diagnosis of Unruptured Intracranial Aneurysm.
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Bio Joo, Hyun Seok Choi, Sung Soo Ahn, Jihoon Cha, So Yeon Won, Beomseok Sohn, Hwiyoung Kim, Kyunghwa Han, Hwa Pyung Kim, Jong Mun Choi, Sang Min Lee, Tae Gyu Kim, and Seung-Koo Lee
- Abstract
Purpose: This study aimed to investigate whether a deep learning model for automated detection of unruptured intracranial aneurysms on time-of-flight (TOF) magnetic resonance angiography (MRA) can achieve a target diagnostic performance comparable to that of human radiologists for approval from the Korean Ministry of Food and Drug Safety as an artificial intelligence-applied software. Materials and Methods: In this single-center, retrospective, confirmatory clinical trial, the diagnostic performance of the model was evaluated in a predetermined test set. After sample size estimation, the test set consisted of 135 aneurysm-containing examinations with 168 intracranial aneurysms and 197 aneurysm-free examinations. The target sensitivity and specificity were set as 87% and 92%, respectively. The patient-wise sensitivity and specificity of the model were analyzed. Moreover, the lesion-wise sensitivity and false-positive detection rate per case were also investigated. Results: The sensitivity and specificity of the model were 91.11% [95% confidence interval (CI): 84.99, 95.32] and 93.91% (95% CI: 89.60, 96.81), respectively, which met the target performance values. The lesion-wise sensitivity was 92.26%. The overall falsepositive detection rate per case was 0.123. Of the 168 aneurysms, 13 aneurysms from 12 examinations were missed by the model. Conclusion: The present deep learning model for automated detection of unruptured intracranial aneurysms on TOF MRA achieved the target diagnostic performance comparable to that of human radiologists. With high standalone performance, this model may be useful for accurate and efficient diagnosis of intracranial aneurysm. [ABSTRACT FROM AUTHOR]
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- 2021
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31. Sex-related associations among anemia, body mass index, and kidney function in Koreans: A cross-sectional study with propensity analysis.
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Tae-Gyu Kim, Sook-Hyun Lee, Sangah Shin, Jae-Heung Cho, Koh-Woon Kim, In-Hyuk Ha, Kim, Tae-Gyu, Lee, Sook-Hyun, Shin, Sangah, Cho, Jae-Heung, Kim, Koh-Woon, and Ha, In-Hyuk
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- 2021
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32. High-flow Nasal Cannula-induced Tension Pneumocephalus.
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Youjin Chang, Tae-Gyu Kim, and Sun-Yoon Chung
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NASAL cannula , *POSITIVE pressure ventilation , *PNEUMOCEPHALUS , *OXYGEN therapy , *SKULL base , *SKULL fractures - Abstract
High-flow nasal cannula (HFNC) therapy has been established as a promising oxygen treatment with various advantages for respiratory mechanics. One of the main mechanisms is to provide positive airway pressure. This effect could reduce lung injury and improve oxygenation; conversely, it may cause a complication of positive pressure ventilation. However, data are scarce regarding the possible adverse effects, particularly in adults. We report a patient who developed HFNC-induced tension pneumocephalus from an unrecognized skull base fracture. Physicians should be cautious when applying HFNC to patients with suspected skull base or paranasal sinus fracture, especially when applying a higher flow rate. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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33. Extraskeletal Ewing’s Sarcoma of the Thoracic Nerve Root: A Case Report.
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Jung Won Kim, Jihae Lee, Jae Hyung Kim, Myeong Ja Jeong, Soung Hee Kim, Ji-Young Kim, Soo Hyun Kim, Mi-Jin Kang, Tae-gyu Kim, Kyung Eun Bae, Jun Jae Shin, Hyun-Jung Kim, and Jung Yeon Kim
- Subjects
EWING'S sarcoma ,SOFT tissue tumors ,COMPUTED tomography - Abstract
Extraskeletal Ewing’s sarcoma (EES) is a rare malignant soft tissue tumor which is morphologically indistinguishable from skeletal ES. EES usually occurs in young adults and children and there has been only one case reported in a patient aged over 70 years old. We report a case of an EES arising from the first thoracic spinal nerve root in a 73-year-old female, which was misdiagnosed as benign nerve sheath tumor in preoperative imaging evaluation. [ABSTRACT FROM AUTHOR]
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- 2019
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34. Feasibility of Selective Neck Irradiation with Lower Elective Radiation Dose in Treating Nasopharynx Cancer Patients.
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Won Kyung Cho, Dongryul Oh, Eonju Lee, Tae Gyu Kim, Hyebin Lee, Heerim Nam, Jae Myoung Noh, and Yong Chan Ahn
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NASOPHARYNX cancer ,RADIATION doses ,CANCER patients ,IRRADIATION ,PROGRESSION-free survival - Abstract
Purpose This study aimed to report the clinical outcomes following selective neck irradiation (SNI) with lower elective radiation therapy (RT) dose in treating nasopharyngeal cancer (NPC) patients. Materials and Methods A total of 347 NPC patients received definitive RT according to our SNI policy and were retrospectively analyzed. The clinical target volumes (CTVs) were subdivided into CTV at high risk (CTV-HR) and CTV at low risk (CTV-LR). The typical doses to gross tumor volume (GTV), CTV-HR, and CTV-LR were 68.4-70.0 Gy, 54.0-60.0 Gy, and 36.0 Gy. Results With the median follow-up of 68.1 months (range, 2.3 to 197.1 months), the 5-year rates of loco-regional control and progression-free survival in all the patients were 85.0% and 70.8%, respectively. Thirty patients developed regional failure and the regional control rates at 3 and 5 years were 92.6% and 91.4%, respectively. The sites of regional failure in relation to the target volume were exclusively inside GTV/CTV-HR in 20, inside and outside GTV/CTVHR in three, and exclusively outside GTV/CTV-HR in seven, which were 5.7%, 0.9%, and 2.0% of total patients, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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35. Efficacy and Safety of Compound Tri-metal Stent Placement for Malignant Perihilar Biliary Obstruction.
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Kwang Min Kim, Chang-Uk Jeong, Sang Goon Shim, Hong Jang, Yun Gyu Song, Tae Gyu Kim, and Jun Ho Ji
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- 2018
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36. Effect of leukocyte alteration on treatment outcomes following preoperative chemoradiotherapy in patients with rectal cancer.
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Tae Gyu Kim, Won Park, Doo Ho Choi, Hee Chul Park, Seok-Hyung Kim, Yong Beom Cho, Seong Hyen Yun, Hee Cheol Kim, Woo Yong Lee, Jeeyun Lee, Joon Oh Park, and Young Suk Park
- Subjects
- *
RECTAL cancer treatment , *CHEMORADIOTHERAPY , *LEUCOCYTES , *PREOPERATIVE care , *BLOOD cell count - Abstract
Purpose: Hematotoxicity following anti-cancer treatment is known to be related to treatment efficacy in several malignancies. The purpose of this study was to examine the hematologic parameters related to the tumor response and survival in patients treated with curative surgery following preoperative chemoradiotherapy (CRT) for rectal cancer. Materials and Methods: Four hundred eighteen patients with rectal cancer who underwent preoperative CRT and curative surgery were analyzed, retrospectively. The main clinical factors and blood cell counts before and after CRT were investigated with respect to their relationships with tumor downstaging and patient survival. Results: The post-CRT leukocyte count was significantly different between the tumor downstaging group and the nondownstaging group (median, 4740/uL vs. 5130/uL; p = 0.013). Multivariate analysis showed that histological grade, circumferential extent, and post-CRT leukocyte count were related to tumor downstaging. In addition, histological grade, post-CRT leukocyte count, and tumor downstaging were related to disease-free survival. The 5-year disease-free survival and overall survival in patients with post-CRT leukocyte count ≤3730/uL, which is the cut-off value derived from the receiver operation characteristic (ROC) curve analysis, were significantly higher than those with higher counts (88.0% vs. 71.6%, p = 0.001; 94.4% vs. 84.1%, p = 0.024). Conclusion: Post-CRT leukocyte count of ≤3730/uL could be regarded as a good prognostic factor for tumor response and survival in rectal cancer patients treated with preoperative CRT. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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37. IMMEDIATE EFFECTS OF SPORTS TAPING APPLIED ON THE LEAD KNEE OF LOW- AND HIGH-HANDICAPPED GOLFERS DURING GOLF SWING.
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TAE-GYU KIM, EUN-KUK KIM, and JONG-CHUL PARK
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GOLF , *GOLF injuries , *KNEE , *PLACEBOS , *PROFESSIONAL athletes , *MOTION capture (Human mechanics) , *TAPING & strapping - Abstract
Elite golf athletes suffer from various musculoskeletal injuries due to repeated golf swings. Repetitive varus moment during golf swing has been suggested as a possible cause of injuries to the lead knee. The aim of this study was to objectively and quantitatively evaluate the immediate effects of sports taping on the lead knee of elite golfers to restrict varus moment. Thirty-one elite golfers were assigned to the low- (LHG, n = 15) or high-handicapped group (HHG, n = 16). Using 3-dimensional motion analysis, the lead knee position on the frontal plane with and without rigid taping (RT), elastic taping (ET), and placebo taping was identified in 4 separate phases by the 5 events of golf swing as follows: the peak of the backswing (E1), parallel to the ground during downswing (E2), ball impact (E3), parallel to the ground during follow-through (E4), and finish (E5). The LHG when using a driver club had decreased movement toward knee varus with RT and ET than that without it from E1 to E2 (p = 0.001). The LHG when using a 5-iron club decreased movement toward knee varus with RT than that without it from E1 to E2 (p = 0.006) and from E2 to E3 (p = 0.019). The HHG when using a driver club had decreased movement toward knee varus with RT from E1 to E2 (p = 0.014). Sports taping may be helpful for elite golfers in terms of reducing varus moment of the lead knee during the downswing and be useful for the development of preventive strategies for golf-related knee injuries. [ABSTRACT FROM AUTHOR]
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- 2017
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38. Comparison of knee characteristics between professional and amateur golfers during the downswing.
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Tae-Gyu Kim, Wi-Young So, Kim, Tae-Gyu, and So, Wi-Young
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GOLFERS , *BIOMECHANICS , *SWING (Golf) , *PHYSICAL training & conditioning , *HUMAN kinematics , *HEALTH , *KNEE physiology , *ATHLETES , *COMPARATIVE studies , *GOLF , *RANGE of motion of joints , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *EVALUATION research , *BODY movement - Abstract
Evaluating the biomechanical and performance factors of the knee joint during golf swing can provide objective and quantitative information about improving the performance and development of efficient physical training, as the legs are important for achieving an efficient swing and maximum speed of the club head in golf. In the present study, kinematic movements of the knee joint were identified during the downswing by using 3-dimensional motion analysis, and isokinetic strength was measured with driver and 5-iron clubs in 15 professional (PRO) golfers and 10 amateur (AMA) golfers. Results showed that PRO golfers had a narrower minimal angle between the thigh and lower leg in the trail knee than the AMA golfers, regardless of the club used, and the angular velocity of the lead knee was faster during the downswing with a 5-iron club in the AMA golfers than in the PRO golfers. The PRO and AMA golfers had a wider minimal angle between the thigh and lower leg, smaller total range of movement, and slower angular velocity of the trail knee when swinging a 5-iron club than when swinging a driver club. These results are expected to provide useful information to prevent golf-related injuries that usually arise in the knee joint and help improve the golf performance of amateur golfers. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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39. High-dose radiation therapy alone by moderate hypofractionation for patients with thoracic esophageal squamous cell carcinoma.
- Author
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Dongryul Oh, Jae Myoung Noh, Nam, Heerim, Hyebin Lee, Tae Gyu Kim, and Yong Chan Ahn
- Published
- 2016
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40. A New Double Trapezoid-Shaped Osteotomy for Reduction Malarplasty.
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Tae Gyu Kim and Young Kyoo Cho
- Published
- 2016
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41. Clinical outcomes of stereotactic body radiotherapy for spinal metastases from hepatocellular carcinoma.
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Eonju Lee, Tae Gyu Kim, Hee Chul Park, Jeong Il Yu, Do Hoon Lim, Heerim Nam, Hyebin Lee, and Joon Hyeok Lee
- Subjects
- *
LIVER cancer , *STEREOTACTIC radiotherapy , *RADIOSURGERY , *ONCOLOGIC surgery , *SPINAL tumors - Abstract
Purpose: To investigate the outcomes of patients with spinal metastases from hepatocellular carcinoma (HCC), who were treated by stereotactic body radiotherapy (SBRT). Materials and Methods: This retrospective study evaluated 23 patients who underwent SBRT from October 2008 to August 2012 for 36 spinal metastases from HCC. SBRT consisted of approximately 2 fractionation schedules, which were 18 to 40 Gy in 1 to 4 fractions for group A lesions (n = 15) and 50 Gy in 10 fractions for group B lesions (n = 21). Results: The median follow-up period was 7 months (range, 2 to 16 months). Seven patients developed grade 1 or 2 gastrointestinal toxicity, and one developed grade 2 leucopenia. Compression fractures occurred in association with 25% of the lesions, with a median time to fracture of 2 months. Pain relief occurred in 92.3% and 68.4% of group A and B lesions, respectively. Radiologic response (complete and partial response) occurred in 80.0% and 61.9% of group A and B lesions, respectively. The estimated 1-year spinal-tumor progression-free survival rate was 78.5%. The median overall survival period and 1-year overall survival rate were 9 months (range, 2 to 16 months) and 25.7%, respectively. Conclusion: SBRT for spinal metastases from HCC is well tolerated and effective at providing pain relief and radiologic response. Because compression fractures develop at a high rate following SBRT for spinal metastases from primary HCC, careful follow up of the patient is required. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
42. EFFECT OF FUNCTIONAL REHABILITATION EXERCISE ON CHRONIC ANKLE INSTABILITY IN ELITE ATHLETES.
- Author
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Tae-Gyu KIM and Wi-Young SO
- Abstract
A functional evaluation (FE) of the effect of a 6-week functional rehabilitation (FR) in elite athletes with chronic ankle instability (CAI) was conducted. Forty-seven athletes (26 male, 21 female) were recruited who trained at Taereung National Training Centre, Seoul in various sport and who had been diagnosed with CAI by means of a medical examination, radiography, ultrasonography, computerised tomography and magnetic resonance imaging. FR consisting of a 4-week neuromuscular training protocol and 6-week dynamic neuromuscular training protocol and was performed 3 to 5 times per week. FE included the Cumberland ankle instability tool (CAIT), stability (static and dynamic), gait (single limb support time; %SLST), isokinetic ankle strength, and kinematic rear foot inversion (RFI) as measured at baseline and at weeks 2, 4, and 6. Descriptive statistics and one-way ANOVA was applied to identify differences across measurement times. CAIT score increased significantly (p<0.001). Both overall stability index (static stability) and test completion time (dynamic stability) decreased significantly (p<0.001). Peak torque/body weight (PT/BW) of dorsiflexion and eversion with eccentric contraction at 60°/s, as well as 120°/s increased significantly (p<0.001). The gait analysis (%SLST) increased significantly (p<0.001), while the RFI angle decreased significantly (p<0.001) during fast walking and running. The 6-week FR was effective. [ABSTRACT FROM AUTHOR]
- Published
- 2015
43. Hardware Implementation of the Fast Optimization Method eDEAS.
- Author
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Tae-gyu Kim, Eun-su Kim, and Jong-wook Kim
- Published
- 2008
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44. Etiologic Factors of Ice Hockey Injuries in Korean High School Players.
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Youn Young Lee, Chang-Hyung Lee, Sun Myung Lee, and Tae Gyu Kim
- Published
- 2014
45. Finite Element Analysis for Shock Resistance Evaluation of Cushion-Packaged Multifunction Printer Considering Internal Modules.
- Author
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Se-Chang Kim, Dae-Geun Cho, Tae-Gyu Kim, Se-Hun Jung, Ja-Choon Koo, Kim, Moon-Ki, and Jae-Boong Choi
- Subjects
FINITE element method ,ELECTRIC shock ,ELECTRIC resistance ,FAILURE analysis ,ELECTRONIC packaging ,COMPUTER printers ,ACCELERATION (Mechanics) ,RELIABILITY in engineering - Abstract
Failures in IT electronics are often caused by falling or external shocks during transpor-tation. These failures cause customers to mistrust the reliability of the products. Many manufacturers of IT electronics have not only used cushioning materials but also increased the shock resistance of their products for failure prevention. Especially in case of printer products, the design of the packaging and the product robustness are extremely important because of their substantial weight and the fragility of the internal modules. For product design, it is essential to understand the impact failure mechanism of the products. In this study, a compression test, a drop impact test, and a finite element analy-sis (FEA) were performed to analyze the dynamic behaviors of a packaged multifunction printer (MFP). The mechanical properties of a cushioning material were measured by compression tests. The FE models of the cushion packaging and the MFP included the physical characteristics of the internal modules, and their dynamic behaviors were obtained using the commercial software LS-DYNA3D. Simulation results were also com-pared with drop test results to verify the proposed FE models. The shock resistance of the MFP was assessed by stress analysis and strength evaluation. We also expect our FE models will be useful for evaluating the fragility of the internal modules because the mod-els can numerically estimate the shock acceleration profiles of the internal modules, which are difficult to measure experimentally. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
46. Endoscopic findings of rectal mucosal damage after pelvic radiotherapy for cervical carcinoma: correlation of rectal mucosal damage with radiation dose and clinical symptoms.
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Tae Gyu Kim, Seung Jae Huh, and Won Park
- Subjects
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RADIOTHERAPY , *CERVICAL cancer treatment , *RADIATION injuries , *RADIATION damage , *ENDOSCOPY - Abstract
Purpose: To describe chronic rectal mucosal damage after pelvic radiotherapy (RT) for cervical cancer and correlate these findings with clinical symptoms and radiation dose. Materials and Methods: Thirty-two patients who underwent pelvic RT were diagnosed with radiation-induced proctitis based on endoscopy findings. The median follow-up period was 35 months after external beam radiotherapy (EBRT) and intracavitary radiotherapy (ICR). The Vienna Rectoscopy Score (VRS) was used to describe the endoscopic findings and compared to the European Organization for Research and Treatment of Cancer (EORTC)/Radiation Therapy Oncology Group (RTOG) morbidity score and the dosimetric parameters of RT (the ratio of rectal dose calculated at the rectal point [RP] to the prescribed dose, biologically effective dose [BED] at the RP in the ICR and EBRT plans, α/β = 3). Results: Rectal symptoms were noted in 28 patients (rectal bleeding in 21 patients, bowel habit changes in 6, mucosal stools in 1), and 4 patients had no symptoms. Endoscopic findings included telangiectasia in 18 patients, congested mucosa in 20, ulceration in 5, and stricture in 1. The RP ratio, BEDICR, BEDICR+EBRT was significantly associated with the VRS (RP ratio, median 76.5%; BEDICR, median 37.1 Gy3; BEDICR+EBRT, median 102.5 Gy3; p < 0.001). The VRS was significantly associated with the EORTC/RTOG score (p = 0.038). Conclusion: The most prevalent endoscopic findings of RT-induced proctitis were telangiectasia and congested mucosa. The VRS was significantly associated with the EORT7 C/RTOG score and RP radiation dose. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
47. CHARACTERISTICS OF DLC FILMS INCORPORATED HMDS BY RF PECVD.
- Author
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TAE GYU KIM, JEONG SEOK OH, HAN KI YOON, and HYE SUNG KIM
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SILICON , *STEEL , *RADIO frequency , *CHEMICAL vapor deposition , *METHANE , *SEALING (Technology) - Abstract
Silicon incorporated diamond-like carbon films up to 6.2 at. % (DLC-Si) were deposited onto a high speed steel samples by using a radio frequency plasma-enhanced chemical vapor deposition method. The influence of silicon doping on chemical composition, bonding structure, hardness, and adhesion of DLC films was investigated. Hexamethyldisilane (HMDS) gas was used as a silicon source with Ar carrier gas ranging from 0 to 15 sccm. Also, the mixtures of methane (CH4) and Ar gases were used as precursor gases. The addition of silicon into the DLC film was found to lead an increase of bonding ratio (sp3/sp2), hardness and critical adhesion [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
48. A STUDY ON THE ROLE OF SINTERING ADDITIVES FOR FABRICATION OF SIC CERAMIC.
- Author
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HAN KI YOON, YOUNG JU LEE, HO JUN CHO, and TAE GYU KIM
- Subjects
SILICON carbide ,SINTERING ,GAS turbines ,FIBER-reinforced ceramics ,EUTECTICS ,MELTING points - Abstract
Silicon carbide (SiC) materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine. The SiC ceramics have been fabricated by a NITE (Nano Infiltration Transient Eutectic Phase) Process, using Nano-SiC powder. The sintering additives used for forming liquid phase under sintering process, used the sintering additives ratios were an Al
2 O3 -Y2 O3 system or add SiO2 contents. A major R&D focus for the SiC ceramics is the production to obtain high purity SiC ceramics. In this study, we investigated roles of the sintering additives(Al2 O3 :Y2 O3 ) to fabrication of the SiC ceramics. The effects of SiO2 contents and density properties of the SiC ceramics were also investigated. To investigate the effects of SiO2 , Al2 O3 /Y2 O3 composition were fixed and then SiO2 ratios were changed as several kinds, and to confirm the effects of sintering additives ratios (Al2 O3 :Y2 O3 ) they were changed between 4:6 and 6:4 in x wt.%. [ABSTRACT FROM AUTHOR]- Published
- 2010
- Full Text
- View/download PDF
49. Lipolysis is stimulated by PEGylated conjugated linoleic acid through the cyclic adenosine monophosphate-independent signaling pathway in 3T3-L1 cells: Activation of MEK/ERK MAPK signaling pathway and hyper-secretion of adipo-cytokines.
- Author
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Hyun-Seuk Moon, Hong-Gu Lee, Ji-Hye Seo, Ding-Ding Guo, In-Yong Kim, Chung-Soo Chung, Tae-Gyu Kim, Yun-Jaie Choi, and Chong-Su Cho
- Subjects
LINOLEIC acid ,CELL culture ,CELL death ,APOPTOSIS ,LIPOLYSIS - Abstract
We previously reported that PEGylated conjugated linoleic acid (PCLA) as a pro-drug treatment of cultures of 3T3-L1 cells containing differentiated adipocytes caused de-differentiation by downregulation of PPARγ2-induced adipogenesis, and cell apoptosis induced by PCLA was lower than that induced by conjugated linoleic acid (CLA) owing to the biocompatible and hydrophilic properties of poly(ethylene glycol) (PEG). To further investigate our previous observations, the present study is designed to evaluate the lipolytic action of PCLA and its role in biochemical signaling pathways of 3T3-L1 cells when compared to the CLA itself. Although both CLA and PCLA stimulated lipolysis, our results indicated a sensitivity difference between CLA and PCLA treatment: a time-dependent effect on lipolysis and p-extracellular signal-related kinases (ERK) expression was observed for PCLA-treated, but not for CLA-treated cultures. Also, the induction by PCLA of mitogen-activated protein kinase kinase (MEK)/ERK mitogen-activated protein kinase (MAPK) activation was linked to secretion of adipo-cytokines, interleukin-6 (IL-6), and interleukin-8 (IL-8), in time-dependent manners. Interestingly, adenylyl cyclase inhibitor, 2′, 5′-dideoxyadenosine (DDA), pre-treatment did not prevent PCLA-stimulated lipolysis. In fact, isoproterenol, but not PCLA, caused a significant increase in cyclic adenosine monophosphate (cAMP) levels, suggesting that the PCLA-induced lipolysis was not mediated in the conventional cAMP-dependent pathway and the cAMP was the intracellular mediator for isoproterenol-induced lipolysis. Overall, our findings provide support for a role for PCLA as a pro-drug in the regulation of metabolism in adipose tissue. J. Cell. Physiol. 214: 283–294, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
50. Inhibitory Effect of (--)-Epigallocatechin-3-Gallate on Lipid Accumulation of 3T3-L1 Cells.
- Author
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Hyun-Seuk Moon, Chung-Soo Chung, Hong-Gu Lee, Tae-Gyu Kim, Yun-Jaie Choi, and Chong-Su Cho
- Subjects
MOLECULES ,CATECHIN ,CELLS ,FAT cells ,HOMEOSTASIS ,LIPIDS ,GLYCERIN ,FATTY acids - Abstract
This article discusses findings of a study which investigated the molecular mechanisms underlying the attenuating effect of (-)-epigallocatechin-3-gallate (EGCG) on the proliferation and lipid accumulation of 3T3-L1 cells. The central role of adipocytes is maintaining lipid homeostasis and energy balance by storing triacylglycerols or releasing free fatty acids in response to changes in energy demands.
- Published
- 2007
- Full Text
- View/download PDF
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