190 results on '"Sung Kwang Park"'
Search Results
2. Kidney transplantation in human immunodeficiency virus-infected patients: a report of two cases and a review of the literatures
- Author
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Hong Pil Hwang, Hee Chul Yu, Kyung Pyo Kang, Won Kim, Sung Kwang Park, Jeong Sang Ku, Hyeongwan Kim, and Sik Lee
- Subjects
human immunodeficiency virus ,kidney transplantation ,Medical technology ,R855-855.5 - Abstract
Human immunodeficiency virus (HIV) infection was traditionally considered an absolute contraindication for transplantation because of concerns about HIV disease progression due to immunosuppression. Since potent antiretroviral therapies (ARTs) have become widely available, the prognosis of HIV-infected kidney transplant recipients has dramatically improved. Recent results of prospective multicenter trials on kidney transplantation (KT) in HIV-positive candidates have demonstrated the success and challenges of transplantation in this population. Several studies have reported comparable patient and graft outcomes between HIV-infected and HIV-uninfected recipients after KT in the era of potent combined ARTs. We report two cases of HIV-infected patients who underwent KT at our hospital. In this paper, we present a detailed report of two cases and provide a short review of the existing literature.
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- 2019
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3. Evaluation of monoxide film-based dosimeters for surface dose detection in electron therapy.
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Moo Jae Han, Seung Woo Yang, Sang Il Bae, Young Min Moon, Wan Jeon, Chul Won Choi, Sung Kwang Park, and Jin Young Kim
- Subjects
Medicine ,Science - Abstract
Generally, electron therapy is applied to tumors on or close to the skin surface. However, this causes a variety of skin-related side effects. To alleviate the risk of these side effects, clinical treatment uses skin dosimeters to verify the therapeutic dose. However, dosimeters suffer from poor accuracy, because their attachment sites are approximated with the help of naked eyes. Therefore, a dosimeter based on a flexible material that can adjust to the contours of the human body is required. In this study, the reproducibility, linearity, dose-rate dependence, and percentage depth ionization (PDI) of PbO and HgO film-based dosimeters are evaluated to explore their potential as large-scale flexible dosimeters. The results demonstrate that both dosimeters deliver impressive reproducibility (within 1.5%) and linearity (≥ 0.9990). The relative standard deviations of the dose-rate dependence of the PbO and HgO dosimeters were 0.94% and 1.16% at 6 MeV, respectively, and 1.08% and 1.25% at 9 MeV, respectively, with the PbO dosimeter outperforming the 1.1% of existing diodes. The PDI analysis of the PbO and HgO dosimeters returned values of 0.014 cm (-0.074 cm) and 0.051 cm (-0.016 cm), respectively at 6 MeV (9 MeV) compared to the thimble chamber and R50. Therefore, the maximum error of each dosimeter is within the allowable range of 0.1 cm. In short, the analysis reveals that the PbO dosimeter delivers a superior performance relative to its HgO counterpart and has strong potential for use as a surface dosimeter. Thus, flexible monoxide materials have the necessary qualities to be used for dosimeters that meet the requisite quality assurance standards and can satisfy a variety of radiation-related applications as flexible functional materials.
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- 2021
- Full Text
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4. Loss of Proximal Tubular Sirtuin 6 Aggravates Unilateral Ureteral Obstruction-Induced Tubulointerstitial Inflammation and Fibrosis by Regulation of β-Catenin Acetylation
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Jixiu Jin, Wenjia Li, Tian Wang, Byung-Hyun Park, Sung Kwang Park, and Kyung Pyo Kang
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kidney fibrosis ,Sirt6 ,β-catenin ,acetylation ,TGF-β1/Smad signaling pathway ,Cytology ,QH573-671 - Abstract
Renal fibrosis is a significant pathologic change associated with progressive kidney disease. Sirt6 is an NAD+-dependent deacetylase and mono-ADP ribosyltransferase known to play diverse roles in the processes attendant to aging, metabolism, and carcinogenesis. However, the role of proximal tubule-specific Sirt6 in renal fibrosis remains elusive. This study investigates the effect of proximal tubule-specific Sirt6 knockdown on unilateral ureteral obstruction (UUO)-induced renal tubulointerstitial inflammation and fibrosis. Renal fibrosis in wild type and PT-Sirt6KO (Sirt6flox/flox; Ggt1-Cre+) mice was induced by UUO surgery. After seven days, histologic examination and Western blot analysis were performed to examine extracellular matrix (ECM) protein expression. We evaluated inflammatory cytokine and cell adhesion molecule expression after ureteral obstruction. The therapeutic effect of Sirt6 activator MDL-800 on UUO-induced tubulointerstitial inflammation and fibrosis was assessed. The loss of Sirt6 in the proximal tubules aggravated UUO-induced tubular injury, ECM deposition, F4/80 positive macrophage infiltration, and proinflammatory cytokine and chemokine expression. Sirt6 activator MDL-800 mitigated UUO-induced renal tubulointerstitial inflammation and fibrosis. In an in vitro experiment, MDL-800 decreases the transforming growth factor (TGF)-β1-induced activation of myofibroblast and ECM production by regulating Sirt6-dependent β-catenin acetylation and the TGF-β1/Smad signaling pathway. In conclusion, proximal tubule Sirt6 may play an essential role in UUO-induced tubulointerstitial inflammation and fibrosis by regulating Sirt6-dependent β-catenin acetylation and ECM protein promoter transcription.
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- 2022
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5. The Degree of Hyperglycemia Excursion in Patients of Kidney Transplantation (KT) or Liver Transplantation (LT) Assessed by Continuous Glucose Monitoring (CGM): Pilot Study
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Heung Yong Jin, Kyung Ae Lee, Yu Ji Kim, Tae Sun Park, Sik Lee, Sung Kwang Park, Hong Pil Hwang, Jae Do Yang, Sung-Woo Ahn, and Hee Chul Yu
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Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Objective. This study used a continuous glucose monitoring system (CGMS) to investigate the glucose profiles and assess the degree of hyperglycemic excursion after kidney or liver transplantation during the early period after operation. Methods. Patients to whom a CGMS was attached during a postoperative period of approximately one month after transplantation were included. The CGM data of 31 patients including 24 with kidney transplantation (KT) and seven with liver transplantation (LT) were analyzed. Results. Hyperglycemia over 126 mg/dL (fasting) or 200 g/dL (postprandial) occurred in 42.1% (8/19) and 16.7% (1/6) of KT and LT patients, respectively, during this early period after transplantation, except for patients with preexisting diabetes (5 KT, 1 LT). The average mean amplitude of glycemic excursion (MAGE) and mean absolute glucose (MAG) levels were 91.18±26.51 vs. 65.66±22.55 (P
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- 2019
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6. Decreased serum level and increased urinary excretion of vascular endothelial growth factor-C in patients with chronic kidney disease
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Sun Hee Kim, Yu Jin Jung, Kyung Pyo Kang, Sik Lee, Sung Kwang Park, Ju-Hyung Lee, Nam Ho Kim, and Won Kim
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Chronic kidney disease ,Hemodialysis ,Hypertension ,VEGF-C ,Internal medicine ,RC31-1245 ,Specialties of internal medicine ,RC581-951 - Abstract
Background: Interstitial tonicity increases vascular endothelial growth factor-C (VEGF-C), a lymphangiogenic factor in salt-induced hypertension. Therefore, it can be assumed that changes of serum VEGF-C level may be associated with increasing blood pressure. However, there is no report about the changes of serum VEGF-C levels in patients with chronic kidney disease (CKD). The aims of this study were to investigate the changes of serum and urine VEGF-C levels in patients with CKD stage 3–4 and to evaluate the relationship between blood pressure and serum VEGF-C levels in the patients with CKD stage 5 and hemodialysis. Methods: Glomerular filtration rate (GFR) was assessed by the Modification of Diet in Renal Disease equation. Blood pressure and VEGF-C levels (serum and urine) were measured by enzyme-linked immunosorbent assay (ELISA) in nine patients with stage 3–4 CKD, 41 hemodialysis patients, and eight healthy individuals. Results: The median serum level of VEGF-C in patients with stage 3–4 CKD and stage 5 hemodialysis significantly decreased in comparison with healthy individuals. Urinary VEGF-C excretion increased in patients with stage 3–4 CKD compared with healthy control patients. For 41 hemodialysis patients, the serum level of VEGF-C in patients with stage 1 or stage 2 hypertension with hemodialysis did not significantly increase when compared with prehypertension hemodialysis patients. Conclusion: We demonstrated that circulating levels of VEGF-C were decreased in patients with CKD, and the decrease of VEGF-C in patients with stage 3–4 CKD coincided with an increase in the urinary excretion of VEGF-C.
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- 2013
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7. Thrombotic microangiopathy resulting from neglected blood pressure control
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Jeong Sang Ku, Won Kim, Sik Lee, Myoung Jae Kang, Sung Kwang Park, and Kyung Pyo Kang
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Hypertension ,Renal failure ,Thrombocytopenia ,Thrombotic microangiopathy ,Internal medicine ,RC31-1245 ,Specialties of internal medicine ,RC581-951 - Abstract
Hypertensive nephrosclerosis is usually associated with chronic hypertension, which increases the risk of progressive renal disease. Among the causes of malignant hypertension, thrombotic microangiopathy is complicated and is associated with renal dysfunction at the time of diagnosis. In this case, a young man with hypertension presented with renal failure and thrombocytopenia in the emergency department. This case emphasizes the importance of early recognition of renal failure and thrombocytopenia among patients with uncontrolled hypertension.
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- 2014
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8. Hemorrhagic fever with renal syndrome and coexisting hantavirus pulmonary syndrome
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Young Min Hong, Jin Chang Moon, Hee Chan Yang, Kyung Pyo Kang, Won Kim, Sung Kwang Park, and Sik Lee
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Hantavirus ,Hantavirus pulmonary syndrome ,Hemorrhagic fever with renal syndrome ,Pulmonary hemorrhage ,Internal medicine ,RC31-1245 ,Specialties of internal medicine ,RC581-951 - Abstract
Hemorrhagic fever with renal syndrome (HFRS) is an acute viral disease with fever, hemorrhage and renal failure caused by hantavirus infection. Hantavirus induces HFRS or hantavirus pulmonary syndrome (HPS). HPS progression to a life-threatening pulmonary disease is found primarily in the USA and very rarely in South Korea. Here, we report a case of HFRS and coexisting HPS.
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- 2012
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9. Evaluation of setup accuracy for prone breast radiotherapy with a three-dimensional surface imaging system
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Young Min Moon, Jin Kyu Kang, To Sol Yu, Wan Jeon, Chul Won Choi, Jin Young Kim, Jin Beom Chung, Sang Won Kang, Sung Kwang Park, Moo Jae Han, and Seung Woo Yang
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General Physics and Astronomy - Published
- 2022
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10. Supplementary Table 1 from Erythropoietin Induces Lymph Node Lymphangiogenesis and Lymph Node Tumor Metastasis
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Won Kim, Suk Ran Yoon, Mi Jung Sung, Suk Tae Lim, Sang Yong Lee, Jae Yong Kwak, Sung Kwang Park, Sik Lee, Kyung Pyo Kang, Yu Jin Jung, Jung Eun Lee, Duk Hoon Kim, and Ae Sin Lee
- Abstract
Supplementary Table 1 from Erythropoietin Induces Lymph Node Lymphangiogenesis and Lymph Node Tumor Metastasis
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- 2023
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11. Evaluation of the Attenuation Rate for Clinical Application of a Flexible Skin Dosimeter in Radiotherapy
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Seung Woo Yang, Moo-Jae Han, Wan Jeon, Jin Young Kim, Jin-Kyu Kang, Jeong-Eun Rah, Seung-Uk Heo, To-Sol Yu, Jin Beom Chung, Young-Min Moon, Sung-Kwang Park, Yohan Shin, and Sang-Il Bae
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010302 applied physics ,Accuracy and precision ,Dosimeter ,Materials science ,Attenuation ,Monte Carlo method ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Particle detector ,Craniospinal Irradiation ,0103 physical sciences ,Irradiation ,0210 nano-technology ,Image resolution ,Biomedical engineering - Abstract
During radiotherapy, some patients owing to the variability in skin sensitivities, may experience adverse skin reactions for doses at which other patients are asymptomatic. Hence, when abnormal symptoms appear on a patient’s skin, the etiology should be verified. Accordingly, a surface dosimeter on the skin can help ascertain whether accurate doses are irradiated. Furthermore, surface doses are measured in the field junction gaps during craniospinal irradiation or during large-area radiotherapy to avoid adverse reactions due to cumulative skin doses from multiple beams. However, the point dose measurement errors of surface dosimeters exceed approximately 10% and have low-positional accuracies because the attachment sites are approximated with the help of the naked eye. Moreover, accurate information on field junction gaps cannot be obtained. Therefore, in clinical practice, a flexible array dosimeter is required as it can measure the dose distribution on the body surface by adapting its shape to the body curvatures. In this study, we implemented a flexible array dosimeter and, based on its constituent materials, evaluated the attenuation rate associated with its use. A polyester (PET) film was used as the underlying substrate. HgI2 and PbI2 photoconductors were used for their good performances in films. Furthermore, the measurement accuracy was verified through comparisons with Monte Carlo simulation outcomes. The resulting PET film had an attenuation rate of 2.22% at a 50-µm thickness. At the minimum material thickness of 25 µm, the attenuation rates for HgI2 and PbI2 were 4.69% and 5.72%, respectively. Further research is needed to fabricate HgI2-based digital skin dosimeters with a thickness under 25 µm. Radiation detection and pixel resolution should be evaluated to accurately confirm the field junction gap.
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- 2020
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12. The tacrolimus metabolism affect post‐transplant outcome mediating acute rejection and delayed graft function: analysis from Korean Organ Transplantation Registry data
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Myoung Soo Kim, Jin Min Kong, Ji Won Min, Tai Yeon Koo, Seung Sik Hwang, Joongyub Lee, Han Ro, Jong Cheol Jeong, Sung Kwang Park, Curie Ahn, and Jaeseok Yang
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Graft Rejection ,medicine.medical_specialty ,Urology ,Delayed Graft Function ,Renal function ,030230 surgery ,Tacrolimus ,Organ transplantation ,03 medical and health sciences ,0302 clinical medicine ,Therapeutic index ,Republic of Korea ,medicine ,Humans ,Registries ,Kidney transplantation ,Transplantation ,business.industry ,Odds ratio ,medicine.disease ,Kidney Transplantation ,Confidence interval ,surgical procedures, operative ,030211 gastroenterology & hepatology ,business ,Immunosuppressive Agents - Abstract
Tacrolimus is a key drug in kidney transplantation (KT) with a narrow therapeutic index. The association between the tacrolimus metabolism rate and KT outcomes have not been investigated in large-scale multi-center studies. The Korean Organ Transplantation Registry (KOTRY) datasets were used. A total of 3456 KT recipients were analyzed. The tacrolimus metabolism rate was defined as blood trough concentration of tacrolimus (C0 ) divided by the daily dose (D). The patients were grouped into fast, intermediate, or slow metabolizers by the C0 /D measured 6 months after transplantation. The slow metabolism group was associated with a 2.7 ml/min/1.73 m2 higher adjusted estimated glomerular filtration rate (eGFR) at 6 months [95% confidence interval (C.I.) 1.2-4.3, P = 0.001], less acute rejection (AR) within 6 months [Odds ratio (OR) 0.744, 95% C.I. 0.585-0.947, P = 0.016], and less interstitial fibrosis and tubular atrophy [OR 0.606, 95% C.I. 0.390-0.940, P = 0.025]. Fast tacrolimus metabolism affected the 6-month post-KT eGFR through mediation of AR [natural indirect effect (NIE) -0.434, 95% C.I. -0.856 to -0.012, P = 0.044) and delayed graft function (DGF; NIE -0.119, 95% C.I. -0.231 to -0.007, P = 0.038). Slow tacrolimus metabolism was associated with better post-KT eGFR. AR and DGF were found to be significant mediators.
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- 2020
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13. A dummy-run evaluation of postoperative hypofractionated intensity-modulated radiation therapy (POHIM-RT) trials for cervical cancer
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Sung Kwang Park, Hee-Jung Kim, Jongwon Kim, Won Soon Park, Jin Hwa Choi, Ki Jung Ahn, Mee Sun Yoon, Ju-Young Song, Jino Bak, Sang-Won Kim, Jeong Geun Oh, Won Kyung Cho, and Kang Kyu Lee
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Organs at Risk ,medicine.medical_specialty ,Imrt plan ,Quality Assurance, Health Care ,cervical cancer ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Planning target volume ,Uterine Cervical Neoplasms ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Regular Paper ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Medical physics ,Postoperative Period ,IMRT ,Protocol (science) ,Cervical cancer ,Radiation ,Kappa value ,hypofractionation ,business.industry ,Radiotherapy Planning, Computer-Assisted ,Intensity-modulated radiation therapy ,medicine.disease ,Radiation therapy ,030220 oncology & carcinogenesis ,AcademicSubjects/SCI00960 ,Female ,Radiation Dose Hypofractionation ,AcademicSubjects/MED00870 ,Radiotherapy, Intensity-Modulated ,Tomography, X-Ray Computed ,business ,Quality assurance - Abstract
The postoperative hypofractionated intensity-modulated radiation therapy (POHIM-RT) trial is a phase II study to evaluate toxicity following hypofractionated intensity modulated radiation therapy (IMRT) for cervical cancer. This study describes the results of a benchmark procedure for RT quality assurance of the POHIM-RT trial. Six participating institutions were provided computed tomography for RT planning and an IMRT plan for a sample and were instructed to delineate volumes, create a treatment plan and quality assurance (QA) plan, and submit the results of all procedures. The inter-institutional agreements on RT volume and plan results were evaluated using the kappa value and dice similarity coefficients. The simultaneous truth and performance level estimation (STAPLE) method was employed to generate a consensus target volume. The treatment volumes, organs-at-risk volumes, and results of the RT plan and QA reported by the institutions were acceptable and adhered well to the protocol. In terms of clinical target volume (CTV) delineation, there were differences between the institutions, particularly in vaginal cuff and paracolpium subsites. Consensus CTV was generated from the collected CTVs with the STAPLE method. The participating institutions showed considerable agreement regarding volume, dose and QA results. To improve CTV agreement in CTV, we provided feedback with images of the consensus target volume and detailed written guidelines for specific subsites that were the most heterogeneous.
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- 2020
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14. Hypofractionated Radiotherapy for Early-Stage Breast Cancer: A Propensity Score Matched Analysis
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Anbok Lee, Hee Yeon Kim, Tae Hyun Kim, Ki Jung Ahn, Heunglae Cho, Sung Kwang Park, and Yunseon Choi
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Humans ,Breast Neoplasms ,Female ,General Medicine ,Neoplasm Recurrence, Local ,Mastectomy, Segmental ,Propensity Score ,Retrospective Studies - Abstract
In patients with early-stage breast cancer, the treatment results of hypofractionated radiation therapy (RT) and conventional RT are evaluated in efficacy and cost.We retrospectively evaluated 280 patients with early-stage (Tis-2N0M0) breast cancer (including 100 hypofractionated RT patients) with regards to treatment outcomes according to the RT schedule. The median whole-breast RT dose was 42.56 Gy/16 fractions for hypofractionated RT and 50.4 Gy/28 fractions for conventional RT. Most patients (n = 260, 92.9%) additionally received a tumor bed boost RT. We used propensity score matching (PSM) analysis to balance the baseline risk factors for recurrence. The co-primary endpoints of this study were disease-free survival (DFS) and ipsilateral breast tumor recurrence (IBTR). DFS or IBTR was analyzed using the Kaplan-Meier survival curve and log-rank test.Total 89 pairs of matched patients (1:1 matching, n = 178) were finally evaluated. The median follow-up was 23.6 months. After matching, the 3-year DFS was 100% in the hypofractionated RT group and 98.4% in the conventional RT group; there was no significant difference in DFS between the groups (Hypofractionated RT showed good IBTR and DFS, which were compatible to those in conventional RT in breast cancer. Hypofractionated RT is expected to be used more widely because of its low cost and convenience.
- Published
- 2021
15. Kidney transplantation in human immunodeficiency virus-infected patients: a report of two cases and a review of the literatures
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Won Kim, Hyeongwan Kim, Kyung Pyo Kang, Hee Chul Yu, Jeong Sang Ku, Sik Lee, Sung Kwang Park, and Hong Pil Hwang
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Transplantation ,medicine.medical_specialty ,education.field_of_study ,business.industry ,medicine.medical_treatment ,Immunology ,Population ,Human immunodeficiency virus (HIV) ,virus diseases ,Immunosuppression ,medicine.disease_cause ,medicine.disease ,Kidney transplant ,Internal medicine ,medicine ,business ,education ,Contraindication ,Kidney transplantation ,Hiv disease - Abstract
Human immunodeficiency virus (HIV) infection was traditionally considered an absolute contraindication for transplantation because of concerns about HIV disease progression due to immunosuppression. Since potent antiretroviral therapies (ARTs) have become widely available, the prognosis of HIV-infected kidney transplant recipients has dramatically improved. Recent results of prospective multicenter trials on kidney transplantation (KT) in HIV-positive candidates have demonstrated the success and challenges of transplantation in this population. Several studies have reported comparable patient and graft outcomes between HIV-infected and HIV-uninfected recipients after KT in the era of potent combined ARTs. We report two cases of HIV-infected patients who underwent KT at our hospital. In this paper, we present a detailed report of two cases and provide a short review of the existing literature.
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- 2019
- Full Text
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16. Evaluation of monoxide film-based dosimeters for surface dose detection in electron therapy
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Sang Il Bae, Wan Jeon, Sung Kwang Park, Young Min Moon, Chul Won Choi, Moo Jae Han, Jin Young Kim, and Seung Woo Yang
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Ionization ,Skin Neoplasms ,medicine.medical_treatment ,Cancer Treatment ,Physical Chemistry ,Electronics Engineering ,Neoplasms ,Medicine and Health Sciences ,Materials ,Skin Tumors ,Multidisciplinary ,Mercury Compounds ,Chemical Reactions ,Linearity ,Oxides ,Equipment Design ,Research Assessment ,Reproducibility ,Chemistry ,Chemical Vapor Deposition ,Oncology ,Process Engineering ,Physical Sciences ,Engineering and Technology ,Medicine ,Research Article ,Clinical Oncology ,Electron therapy ,Materials science ,Film Dosimetry ,Science ,Materials Science ,Radiation Therapy ,Electrons ,Dermatology ,Industrial Processes ,Research and Analysis Methods ,Skin surface ,Industrial Engineering ,medicine ,Binders ,Dosimetry ,Humans ,Diode ,Dosimeter ,Surface Treatments ,Cancers and Neoplasms ,Monoxide ,Diodes ,Chemical Deposition ,Semiconductors ,Manufacturing Processes ,Lead ,Electronics ,Clinical Medicine ,Biomedical engineering - Abstract
Generally, electron therapy is applied to tumors on or close to the skin surface. However, this causes a variety of skin-related side effects. To alleviate the risk of these side effects, clinical treatment uses skin dosimeters to verify the therapeutic dose. However, dosimeters suffer from poor accuracy, because their attachment sites are approximated with the help of naked eyes. Therefore, a dosimeter based on a flexible material that can adjust to the contours of the human body is required. In this study, the reproducibility, linearity, dose-rate dependence, and percentage depth ionization (PDI) of PbO and HgO film-based dosimeters are evaluated to explore their potential as large-scale flexible dosimeters. The results demonstrate that both dosimeters deliver impressive reproducibility (within 1.5%) and linearity (≥ 0.9990). The relative standard deviations of the dose-rate dependence of the PbO and HgO dosimeters were 0.94% and 1.16% at 6 MeV, respectively, and 1.08% and 1.25% at 9 MeV, respectively, with the PbO dosimeter outperforming the 1.1% of existing diodes. The PDI analysis of the PbO and HgO dosimeters returned values of 0.014 cm (–0.074 cm) and 0.051 cm (–0.016 cm), respectively at 6 MeV (9 MeV) compared to the thimble chamber and R50. Therefore, the maximum error of each dosimeter is within the allowable range of 0.1 cm. In short, the analysis reveals that the PbO dosimeter delivers a superior performance relative to its HgO counterpart and has strong potential for use as a surface dosimeter. Thus, flexible monoxide materials have the necessary qualities to be used for dosimeters that meet the requisite quality assurance standards and can satisfy a variety of radiation-related applications as flexible functional materials.
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- 2021
17. Development and Evaluation of Monoxide Based Flexible Skin Dosimeter for Radiotherapy at Photon Energies
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Tosol Yu, Jin-Kyu Kang, Seung Woo Yang, Jin-Beom Chung, Moo-Jae Han, Manwoo Lee, Jeong-Eun Rah, Sung-Kwang Park, Jung-Ki Kim, and Jin Young Kim
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Radiation therapy ,Dosimeter ,Photon ,Materials science ,business.industry ,medicine.medical_treatment ,medicine ,Optoelectronics ,Monoxide ,business - Abstract
Radiation therapy uses high-energy radiation that can cause various side effects depending on the patient's exposure. In particular, side effects occur in the skin due to its radiation exposure to reach the target volume. Therefore, side effects are reduced by clinical trials using various skin dosimeters such as films and glass detectors to determine the dose exposed to the skin. However, accurately measuring the doses using these dosimeters is challenging due to human curvature. In this study, a flexible skin dosimeter was produced using the photoconductor materials mercury oxide (HgO) and lead oxide (PbO). The performance of the proposed dosimeter was evaluated by measuring reproducibility, linearity, dose rate independency according to dose, and percent depth dose (PDD) at photon energy beam. The results showed that the flexible skin dosimeter using HgO material has high applicability as a skin dosimeter due to its stability compared to PbO. The results provide useful insights for the radiation therapy field, particularly in areas where radiation measurement is difficult, depending on the human curvature. The proposed flexible skin dosimeter could serve in various radiation detection areas as a flexible, functional material
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- 2020
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18. P0271SERUM VASCULAR ENDOTHELIAL GROWTH FACTOR-D LEVEL CORRELATES WITH RENAL FUNCTION AND ALBUMINURIA IN PATIENT WITH DIABETIC CHRONIC KIDNEY DISEASE
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Jong Hwan Chong, Won Kim, Hyeongwan Kim, Sung Kwang Park, and Woong Park
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Transplantation ,medicine.medical_specialty ,business.industry ,Urology ,Vascular Endothelial Growth Factor D ,Renal function ,urologic and male genital diseases ,medicine.disease ,female genital diseases and pregnancy complications ,Nephrology ,Albuminuria ,medicine ,In patient ,medicine.symptom ,business ,Kidney disease - Abstract
Background and Aims Biomarkers associated with chronic kidney disease (CKD) may play a crucial role in patients with diabetic kidney diseases. Vascular endothelial growth factor (VEGF)-C and VEGF-D are lymphangiogenic growth factors. It has been well demonstrated that there is lympnagiogenesis in fibrotic kidney disease in human. Previously, we showed that renal VEGF-C and VEGF-D are involved in lymphangiogensis in renal fibrosis model. Recent studies have shown a relationship between sodium load and serum VEGF-C levels in hypertensive patients. Lymphatic endothelial proliferation has been detected in diabetic nephropathy. Thus, serum VEGF-C level has been introduced as a candidate marker of chronic kidney disease. However, until now, there have been few report about serum VEGF-D in patients with diabetic CKD. Thus, we evaluated the relationships between serum VEGF-D and renal function and albuminuria of diabetic CKD. Method We divided diabetic CKD patients into four groups: CKD stage 3, CKD stage 4, and CKD stage 5 (without dialysis). Total forty two Asian patients with diabetic CKD (14 patients with CKD stage 3, 14 patients with CKD stage 4 and 14 patients with CKD stage 5) and seven healthy controls without diabetes mellitus have been enrolled in this study. In this cross-sectional study, we performed comparative analysis with serum level of VEGF-D in patients with each group. We measured the levels of VEGF-D through the multiplexing using Luminex® technology. Results The serum levels of VEGF-D were higher in the CKD 3, CKD 4 and CKD 5 group compared with the control group (25.9±5.6 pg/ml in control group, 60.3±9.7in stage 3, 62.9±8.5 in stage 4, and 66.5±8.0 in stage 5). However, there was not a significant difference between CKD stage III or IV and CKD stage V in serum levels of VEGF-D. Serum VEGF-D level were negatively correlated with estimated glomerular filtration rate and positively correlated with serum creatinine. At GFR level ≥60 ml/min per 1.73 m2, serum VEGF-D were biomarkers in ROC analysis. There was a positive correlation between serum VEGF-D level and albuminuria in patient with diabetic CKD. We also found that serum VEGF-D level also correlated with urine protein-to-creatinine ratio in patient with diabetic CKD. Conclusion Serum VEGF-D is correlated with renal function in patients with diabetic CKD. VEGF levels in the serum correlate to the severity of proteinuria and albuminuria in diabetic CKD patients. Further large-scale studies are required to confirm these findings.
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- 2020
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19. Absence of Sirt3 aggravates cisplatin nephrotoxicity via enhanced renal tubular apoptosis and inflammation
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Kyung Pyo Kang, Woong Park, Sik Lee, Sung Kwang Park, Dal Kim, and Won Kim
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0301 basic medicine ,Cancer Research ,SIRT3 ,cisplatin ,Inflammation ,Antineoplastic Agents ,Pharmacology ,sirtuin 3 ,medicine.disease_cause ,Biochemistry ,Nephrotoxicity ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,medicine ,Animals ,Molecular Biology ,Cisplatin ,Mice, Knockout ,Kidney ,biology ,Chemistry ,apoptosis ,Articles ,030104 developmental biology ,medicine.anatomical_structure ,Kidney Tubules ,Oncology ,acute kidney injury ,Apoptosis ,030220 oncology & carcinogenesis ,Sirtuin ,biology.protein ,Molecular Medicine ,Kidney Diseases ,medicine.symptom ,Oxidative stress ,Gene Deletion ,medicine.drug - Abstract
Cisplatin-based chemotherapy is commonly used in the treatment of solid tumors; however, this agent is limited by its adverse effects on normal tissues, including the kidneys, ears and peripheral nerves. Mechanisms of cisplatin nephrotoxicity are proposed to involve oxidative stress, inflammation, cellular apoptosis and cell cycle regulation. Sirtuin 3 (Sirt3) is a member of the sirtuin family of NAD+-dependent enzymes with homology to Saccharomyces cerevisiae gene silent information regulator 2. Sirt3 is located in mitochondria and is involved in mitochondrial energy metabolism and function; however, the role of Sirt3 in cisplatin nephrotoxicity remains unclear. In the present study, whether Sirt3 has anti-inflammatory and anti-apoptotic effects on cisplatin-induced nephrotoxicity was investigated in mice. Sirt3 knockout mice (Sirt3(−/−)) and corresponding wild type mice were employed in the present study. Cisplatin nephrotoxicity was induced by intraperitoneal injection of cisplatin (20 mg/kg). After 3 days following cisplatin treatment, blood and kidney tissues were harvested. Renal function and histology were evaluated. Tubular apoptosis, cell adhesion molecule expression, and inflammatory cells were evaluated by immunohistochemistry and western blot analysis. Following the induction of cisplatin nephrotoxicity, renal function was significantly aggravated in Sirt3 knockout (KO) mice. Tubular injury and inflammatory cell infiltration were significantly increased in Sirt3KO mice compared with wild type mice. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end label-positive tubular cells and renal monocyte chemoattractant protein-1 expression levels were increased in Sirt3KO mice compared with in wild type mice. In summary, the absence of Sirt3 aggravated in renal injury by increasing renal inflammation and tubular apoptosis. The results of the present study suggested that Sirt3 may have an important role in cisplatin-induced nephrotoxicity.
- Published
- 2018
20. Graft lymphoma in a kidney transplant recipient: a case report
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Byeoung Hoon Chung, Hong Pil Hwang, Hee Chul Yu, Keun-Sang Kwon, Sung Kwang Park, Sik Lee, and Ji-Hyun Yeom
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Kidney transplant recipient ,medicine.medical_specialty ,business.industry ,medicine ,medicine.disease ,business ,Lymphoma ,Surgery - Published
- 2021
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21. Feasibility study on an integrated AEC-grid device for the optimization of image quality and exposure dose in mammography
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Kyo-Tae Kim, Ryang-Young Yun, Kyeong-Min Oh, Sung-Wook Heo, Ye-Ji Heo, Yongkeun Song, Moo-Jae Han, and Sung-Kwang Park
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medicine.medical_specialty ,medicine.diagnostic_test ,Computer science ,Radiographic equipment ,Image quality ,Real-time computing ,Detector ,General Physics and Astronomy ,Early detection ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Grid ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Mammography ,Medical physics ,0210 nano-technology ,Automatic exposure control - Abstract
Currently, in the radiation diagnosis field, mammography is used for the early detection of breast cancer. In addition, studies are being conducted on a grid to produce high-quality images. Although the grid ratio of the grid, which affects the scattering removal rate, must be increased to improve image quality, it increases the total exposure dose. While the use of automatic exposure control is recommended to minimize this problem, existing mammography equipment, unlike general radiography equipment, is mounted on the back of a detector. Therefore, the device is greatly affected by the detector and supporting device, and it is difficult to control the exposure dose. Accordingly, in this research, an integrated AEC-grid device that simultaneously performs AEC and grid functions was used to minimize the unnecessary exposure dose while removing scattering, thereby realizing superior image quality.
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- 2017
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22. The Study on Design of Semiconductor Detector for Checking the Position of a Radioactive Source in an NDT
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Sung-Kwang Park, Ye-Ji Heo, Ki-Jung Ahn, Joo-Hee Kim, Moo-Jae Han, and Kyo-Tae Kim
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business.industry ,Radioactive source ,010403 inorganic & nuclear chemistry ,01 natural sciences ,030218 nuclear medicine & medical imaging ,0104 chemical sciences ,Semiconductor detector ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Position (vector) ,Nondestructive testing ,Medicine ,business ,Nuclear medicine - Published
- 2017
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23. FP024Inhibition of YAP by Verteporfin decreases TGF-β1 induced renal fibroblast activation by regulation of TGF-β1/Smad signaling pathway
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Jeong Sang Ku, Won Bae Kim, Kyung Pyo Kang, Sik Lee, Sung Kwang Park, Jixiu Jin, and Woong Park
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Transplantation ,medicine.anatomical_structure ,Nephrology ,business.industry ,medicine ,Cancer research ,SMAD ,Signal transduction ,business ,Fibroblast ,Verteporfin ,medicine.drug ,Transforming growth factor - Published
- 2019
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24. Maximum standardized uptake value at pre-treatment PET in estimating lung cancer progression after stereotactic body radiotherapy
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Heunglae Cho, Ji Sun Park, Ji Young Lee, Ki Jung Ahn, Yunseon Choi, and Sung Kwang Park
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Stereotactic body radiotherapy ,Clinical Investigations ,Standardized uptake value ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Lung neoplasms ,medicine ,Radiology, Nuclear Medicine and imaging ,Progression-free survival ,Stage (cooking) ,Lung cancer ,medicine.diagnostic_test ,Receiver operating characteristic ,business.industry ,medicine.disease ,Oncology ,Positron emission tomography ,030220 oncology & carcinogenesis ,T-stage ,Original Article ,Positron-emission tomography ,business ,Nuclear medicine ,Wedge resection (lung) - Abstract
Purpose This study aimed to identify the feasibility of the maximum standardized uptake value (SUVmax) on baseline 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) as a predictive factor for prognosis in early stage primary lung cancer treated with stereotactic body radiotherapy (SBRT). Materials and methods Twenty-seven T1-3N0M0 primary lung cancer patients treated with curative SBRT between 2010 and 2018 were retrospectively evaluated. Four patients (14.8%) treated with SBRT to address residual tumor after wedge resection and one patient (3.7%) with local recurrence after resection were included. The SUVmax at baseline PET/CT was assessed to determine its relationship with prognosis after SBRT. Patients were divided into two groups based on maximum SUVmax on pre-treatment FDG PET/CT, estimated by receiver operating characteristic curve. Results The median follow-up period was 17.7 months (range, 2.3 to 60.0 months). The actuarial 2-year local control, progressionfree survival (PFS), and overall survival were 80.4%, 66.0%, and 78.2%, respectively. With regard to failure patterns, 5 patients exhibited local failure (in-field failure, 18.5%), 1 (3.7%) experienced regional nodal relapse, and other 2 (7.4%) developed distant failure. SUVmax was significantly correlated with progression (p = 0.08, optimal cut-off point SUVmax > 5.1). PFS was significantly influenced by pretreatment SUVmax (SUVmax > 5.1 vs. SUVmax ≤ 5.1; p = 0.012) and T stage (T1 vs. T2-3; p = 0.012). Conclusion SUVmax at pre-treatment FDG PET/CT demonstrated a predictive value for PFS after SBRT for lung cancer.
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- 2019
25. The Degree of Hyperglycemia Excursion in Patients of Kidney Transplantation (KT) or Liver Transplantation (LT) Assessed by Continuous Glucose Monitoring (CGM): Pilot Study
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Sung Kwang Park, Heung Yong Jin, Kyung Ae Lee, Yu Ji Kim, Hong Pil Hwang, Sung Woo Ahn, Sik Lee, Hee Chul Yu, Jae Do Yang, and Tae Sun Park
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Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,Time Factors ,Article Subject ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Pilot Projects ,Liver transplantation ,Gastroenterology ,Severity of Illness Index ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Endocrinology ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,Diabetes mellitus ,Medicine ,Humans ,Kidney transplantation ,Glycemic ,Retrospective Studies ,lcsh:RC648-665 ,business.industry ,Blood Glucose Self-Monitoring ,Reproducibility of Results ,Immunosuppression ,Middle Aged ,medicine.disease ,Kidney Transplantation ,Liver Transplantation ,Transplantation ,Postprandial ,Treatment Outcome ,Predictive value of tests ,Hyperglycemia ,Female ,business ,Biomarkers ,Research Article - Abstract
Objective. This study used a continuous glucose monitoring system (CGMS) to investigate the glucose profiles and assess the degree of hyperglycemic excursion after kidney or liver transplantation during the early period after operation. Methods. Patients to whom a CGMS was attached during a postoperative period of approximately one month after transplantation were included. The CGM data of 31 patients including 24 with kidney transplantation (KT) and seven with liver transplantation (LT) were analyzed. Results. Hyperglycemia over 126 mg/dL (fasting) or 200 g/dL (postprandial) occurred in 42.1% (8/19) and 16.7% (1/6) of KT and LT patients, respectively, during this early period after transplantation, except for patients with preexisting diabetes (5 KT, 1 LT). The average mean amplitude of glycemic excursion (MAGE) and mean absolute glucose (MAG) levels were 91.18±26.51 vs. 65.66±22.55 (P<0.05) and 24.62±7.78 vs. 18.18±7.07 (P<0.05) in KT vs. LT patients, respectively, in patients without preexisting DM or PTDM patients who showed normal glucose levels. Average increase from the lowest level to the peak glucose value was higher in KT patients than LT patients (P<0.05). Conclusions. The transplanted organ also needs to be considered as an important factor affecting glucose control and the occurrence of more severe glucose excursions in patients who receive transplantation although immunosuppression agents are well-known important factors; however, our study was limited to the early posttransplantation period. Further studies involving CGM follow-up at regular intervals based on the time since transplantation are needed.
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- 2019
26. Adverse effect of excess body weight on survival in cervical cancer patients after surgery and radiotherapy
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Heung lae Cho, Sung Kwang Park, Ji Young Lee, Ki Jung Ahn, and Yun seon Choi
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0301 basic medicine ,medicine.medical_specialty ,Survival ,medicine.medical_treatment ,Overweight ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Radiology, Nuclear Medicine and imaging ,Clinical Investigation ,Obesity ,Adverse effect ,Lymph node ,Cervical cancer ,Radiotherapy ,business.industry ,medicine.disease ,Surgery ,Radiation therapy ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Original Article ,Lymph ,medicine.symptom ,Underweight ,Erratum ,business ,Body mass index - Abstract
Purpose This study aimed to assess the effects of body mass index (BMI) on survival in cervical cancer patients who had undergone surgery and radiotherapy (RT). Materials and methods We retrospectively reviewed the medical records of 70 cervical cancer patients who underwent surgery and RT from 2007 to 2012. Among them, 40 patients (57.1%) had pelvic lymph node metastases at the time of diagnosis. Sixty-seven patients (95.7%) had received chemotherapy. All patients had undergone surgery and postoperative RT. Median BMI of patients was 22.8 kg/m2 (range, 17.7 to 35.9 kg/m2). Results The median duration of follow-up was 52.3 months (range, 16 to 107 months). Twenty-four patients (34.3%) showed recurrence. Local failure, regional lymph nodal failure, and distant failure occurred in 4 (5.7%), 6 (8.6%), and 17 (24.3%) patients, respectively. The 5-year actuarial pelvic control rate was 83.4%. The 5-year cancer-specific survival (CSS) and disease-free survival (DFS) rates were 85.1% and 65.0%, respectively. The presence of pelvic lymph node metastases (n = 30) and being overweight or obese (n = 34, BMI ≥ 23 kg/m2) were poor prognostic factors for CSS (p = 0.003 and p = 0.045, respectively). Of these, pelvic lymph node metastasis was an independent prognostic factor (p = 0.030) for CSS. Conclusion Overweight or obese cervical cancer patients showed poorer survival outcomes than normal weight or underweight patients. Weight control seems to be important in cervical cancer patients to improve clinical outcomes.
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- 2016
27. KERMA-based radiation dose management system for real-time patient dose measurement
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Kyung-Min Oh, Sung-Kwang Park, Sang-Sik Kang, Sang-Hee Nam, Ye-Ji Heo, Kyo-Tae Kim, Ji-Koon Park, and Yongkeun Song
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010302 applied physics ,medicine.medical_specialty ,business.industry ,Radiography ,Radiation dose ,General Physics and Astronomy ,Radiation ,01 natural sciences ,030218 nuclear medicine & medical imaging ,Radiation exposure ,03 medical and health sciences ,Kerma ,0302 clinical medicine ,0103 physical sciences ,Management system ,medicine ,Dosimetry ,Medical physics ,Patient dose ,business - Abstract
Because systems that reduce radiation exposure during diagnostic procedures must be developed, significant time and financial resources have been invested in constructing radiation dose management systems. In the present study, the characteristics of an existing ionization-based system were compared to those of a system based on the kinetic energy released per unit mass (KERMA). Furthermore, the feasibility of using the KERMA-based system for patient radiation dose management was verified. The ionization-based system corrected the effects resulting from radiation parameter perturbations in general radiography whereas the KERMA-based system did not. Because of this difference, the KERMA-based radiation dose management system might overestimate the patient’s radiation dose due to changes in the radiation conditions. Therefore, if a correction factor describing the correlation between the systems is applied to resolve this issue, then a radiation dose management system can be developed that will enable real-time measurement of the patient’s radiation exposure and acquisition of diagnostic images.
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- 2016
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28. Association between obesity and local control of advanced rectal cancer after combined surgery and radiotherapy
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Heunglae Cho, Yunseon Choi, Sung Kwang Park, Yun-Han Lee, and Ki Jung Ahn
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0301 basic medicine ,medicine.medical_specialty ,Colorectal cancer ,medicine.medical_treatment ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Radiology, Nuclear Medicine and imaging ,Clinical Investigation ,Obesity ,Stage (cooking) ,Rectal cancer ,Lymph node ,Radiotherapy ,business.industry ,Medical record ,Cancer ,medicine.disease ,Prognosis ,Surgery ,Radiation therapy ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,Local control ,030220 oncology & carcinogenesis ,Original Article ,business ,Body mass index - Abstract
Purpose The association between metabolism and cancer has been recently emphasized. This study aimed to find the prognostic significance of obesity in advanced stage rectal cancer patients treated with surgery and radiotherapy (RT). Materials and methods We retrospectively reviewed the medical records of 111 patients who were treated with combined surgery and RT for clinical stage 2-3 (T3 or N+) rectal cancer between 2008 and 2014. The prognostic significance of obesity (body mass index [BMI] ≥25 kg/m(2)) in local control was evaluated. Results The median follow-up was 31.2 months (range, 4.1 to 85.7 months). Twenty-five patients (22.5%) were classified as obese. Treatment failure occurred in 33 patients (29.7%), including local failures in 13 patients (11.7%), regional lymph node failures in 5, and distant metastases in 24. The 3-year local control, recurrence-free survival, and overall survival rates were 88.7%, 73.6%, and 87.7%, respectively. Obesity (n = 25) significantly reduced the local control rate (p = 0.045; 3-year local control, 76.2%), especially in women (n = 37, p = 0.021). Segregation of local control was best achieved by BMI of 25.6 kg/m(2) as a cutoff value. Conclusion Obese rectal cancer patients showed poor local control after combined surgery and RT. More effective local treatment strategies for obese patients are warranted.
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- 2016
29. Setup uncertainties for inter-fractional head and neck cancer in radiotherapy
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Eun–Tae Park and Sung Kwang Park
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Adult ,Male ,medicine.medical_treatment ,Statistical difference ,cervical spine ,setup error ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Statistical significance ,medicine ,Humans ,Aged ,Aged, 80 and over ,business.industry ,Radiotherapy Planning, Computer-Assisted ,Head and neck cancer ,Uncertainty ,Dose fractionation ,organ motion ,Middle Aged ,medicine.disease ,Cervical spine ,Radiation therapy ,medicine.anatomical_structure ,Oncology ,Head and Neck Neoplasms ,030220 oncology & carcinogenesis ,Cervical Vertebrae ,Female ,head and neck cancer ,Dose Fractionation, Radiation ,Clinical Research Paper ,Tomography, X-Ray Computed ,Nuclear medicine ,business ,Student's t-test ,Cervical vertebrae - Abstract
// Eun-Tae Park 1 , Sung Kwang Park 1 1 Department of Radiation Oncology, Busan Paik Hospital, Inje University School of Medicine, Busan, Korea Correspondence to: Sung Kwang Park, email: physicist@paik.ac.kr Keywords: head and neck cancer, setup error, cervical spine, organ motion Received: March 07, 2016 Accepted: April 27, 2016 Published: May 31, 2016 ABSTRACT Purpose: The aim of this study is to determine the inter-fractional motion of cervical spine in radiotherapy (RT). Materials and Methods: Eleven localized head and neck cancer patients who were treated from April 2014 to September 2015 were evaluated. Every patient underwent 3 times of computed tomography (CT) simulation with equivalent setting. Left-right (LR, x) and antero-posterior (AP, z) directional shift of cervical spine were evaluated using 33 number of CT image. In regard to random error, geometric changes were evaluated by 22 data set (compared the first obtained CT to second or third CT) by one-sample T test. Systemic error was evaluated by each patients’ data set (11 pairs) by paired T test. Results: The mean random error of LR and AP translational shift of cervical spine were −0.39 ± 3.24 mm and −0.57 ± 0.99 mm respectively. The mean random error of translational change of AP direction showed statistical significance ( p = 0.014). The mean random error of x and z rotational shift were −0.07 ± 0.29° and −0.05 ± 0.35°, respectively. The mean systemic error of translational shift of LR and AP direction were −0.64 ± 2.57 mm and −0.33 ± 1.22 mm, respectively. The mean systemic error of rotational shift of x and z were 0.01 ± 0.18° and −0.27 ± 0.33°, respectively. The mean systemic error of rotational changes of z direction showed statistical difference ( p = 0.022). Conclusions: We have to be aware of the inter-fractional motion of cervical spine in head and neck RT and give enough margins in RT planning.
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- 2016
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30. Efficacy of Dose-Escalated Radiotherapy for Recurrent Colorectal Cancer
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Heunglae Cho, Hyun-Jung Kim, Ki Jung Ahn, Sunmi Jo, Sung Kwang Park, Jin-Young Kim, Won-Yong Oh, Yun-Han Lee, and Yunseon Choi
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Oncology ,medicine.medical_specialty ,Disease free survival ,Radiotherapy ,Dose escalation ,business.industry ,Disease-free survival ,medicine.medical_treatment ,Gastroenterology ,Rectal neoplasms ,Radiation therapy ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,030220 oncology & carcinogenesis ,Internal medicine ,medicine ,030211 gastroenterology & hepatology ,Surgery ,Recurrent Colorectal Cancer ,Original Article ,business - Abstract
Purpose This study aimed to evaluate the effects of radiotherapy (RT) on progression-free survival (PFS) for patients with recurrent colorectal cancer. Methods We reviewed the records of 22 patients with recurrent colorectal cancer treated with RT between 2008 and 2014. The median radiation dose for recurrent disease was 57.6 Gy (range, 45–75.6 Gy). Patients were divided into 2 groups according to the type of RT: patients underwent RT without previous history of irradiation (n = 14) and those treated with secondary RT (reirradiation: n = 8) at the time of recurrence. Results The median follow-up period was 24.9 months (range, 4.5–66.6 months). Progression was observed in 14 patients (including 8 with loco-regional failure and 9 with distant metastases). Distant metastases were related to the RT dose (
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- 2016
31. Inhibition of Yes-Associated Protein by Verteporfin Ameliorates Unilateral Ureteral Obstruction-Induced Renal Tubulointerstitial Inflammation and Fibrosis
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Woong Park, Sung Kwang Park, Wenjia Li, Kyung Pyo Kang, Tian Wang, Jixiu Jin, and Won Kim
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Male ,0301 basic medicine ,Hippo pathway ,kidney fibrosis ,030232 urology & nephrology ,Cell Cycle Proteins ,SMAD ,urologic and male genital diseases ,lcsh:Chemistry ,Mice ,0302 clinical medicine ,Fibrosis ,lcsh:QH301-705.5 ,Cells, Cultured ,Spectroscopy ,Photosensitizing Agents ,verteporfin ,General Medicine ,Verteporfin ,Computer Science Applications ,myofibroblast activation ,Kidney Diseases ,medicine.symptom ,Signal transduction ,Myofibroblast ,Ureteral Obstruction ,medicine.drug ,extracellular matrix ,Inflammation ,Article ,Catalysis ,Inorganic Chemistry ,03 medical and health sciences ,medicine ,Renal fibrosis ,Animals ,Physical and Theoretical Chemistry ,Molecular Biology ,Adaptor Proteins, Signal Transducing ,Hippo signaling pathway ,urogenital system ,business.industry ,Organic Chemistry ,YAP-Signaling Proteins ,medicine.disease ,Rats ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,inflammation ,Cancer research ,business - Abstract
Yes-associated protein (YAP) activation after acute ischemic kidney injury might be related to interstitial fibrosis and impaired renal tubular regeneration. Verteporfin (VP) is a photosensitizer used in photodynamic therapy to treat age-related macular degeneration. In cancer cells, VP inhibits TEA domain family member (TEAD)-YAP interactions without light stimulation. The protective role of VP in unilateral ureteral obstruction (UUO)-induced renal fibrosis and related mechanisms remains unclear. In this study, we investigate the protective effects of VP on UUO-induced renal tubulointerstitial inflammation and fibrosis and its regulation of the transforming growth factor-&beta, 1 (TGF-&beta, 1)/Smad signaling pathway. We find that VP decreased the UUO-induced increase in tubular injury, inflammation, and extracellular matrix deposition in mice. VP also decreased myofibroblast activation and proliferation in UUO kidneys and NRK-49F cells by modulating Smad2 and Smad3 phosphorylation. Therefore, YAP inhibition might have beneficial effects on UUO-induced tubulointerstitial inflammation and fibrosis by regulating the TGF-&beta, 1/Smad signaling pathway.
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- 2020
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32. THE KOREAN ORGAN TRANSPLANTATION REGISTRY (KOTRY): FIRST OFFICIAL KIDNEY TRANSPLANTATION REPORT
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Sung Kwang Park, Su Hyung Lee, Curie Ahn, Jong Cheol Jeong, Yeon Ho Park, Jaeseok Yang, and Tai Yeon Koo
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Transplantation ,medicine.medical_specialty ,business.industry ,Medicine ,business ,medicine.disease ,Organ transplantation ,Kidney transplantation ,Surgery - Published
- 2020
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33. LONG-TERM OUTCOMES OF FULL-THICKNESS TECHNIQUE FOR URETERONEOCYSTOSTOMY IN RENAL TRANSPLANTATION
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Jae Do Yang, Suk Seong, Myung Ki Kim, Hong Pil Hwang, Byeoung Hoon Chung, Kyoung Hee Hwang, Sung Kwang Park, Hee Chul Yu, Sun Myung Lee, Sung Woo Ahn, and Sik Lee
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Transplantation ,medicine.medical_specialty ,business.industry ,Long term outcomes ,Medicine ,Full thickness ,business ,Surgery - Published
- 2020
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34. NUTRITIONAL ASSESSMENT AFTER KIDNEY TRANSPLANTATION USING BIOELECTRICAL IMPEDANCE AND GRAFT FUNCTION
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Sun Myung Lee, Sik Lee, Jae Do Yang, Sung Woo Ahn, Hee Chul Yu, Hong Pil Hwang, Byeoung Hoon Chung, Kyoung Hee Hwang, Suk Seong, Myung Ki Kim, and Sung Kwang Park
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Transplantation ,medicine.medical_specialty ,business.industry ,Urology ,medicine ,business ,medicine.disease ,Bioelectrical impedance analysis ,Graft function ,Kidney transplantation - Published
- 2020
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35. Sirtuin 3 Activation by Honokiol Decreases Unilateral Ureteral Obstruction-Induced Renal Inflammation and Fibrosis via Regulation of Mitochondrial Dynamics and the Renal NF-κB-TGF-β1/Smad Signaling Pathway
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Kyung Pyo Kang, Won Kim, Jixiu Jin, Yi Quan, Sung Kwang Park, and Woong June Park
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0301 basic medicine ,kidney fibrosis ,Smad Proteins ,SMAD ,urologic and male genital diseases ,Mitochondrial Dynamics ,lcsh:Chemistry ,Mice ,0302 clinical medicine ,Sirtuin 3 ,lcsh:QH301-705.5 ,Spectroscopy ,biology ,Chemistry ,NF-kappa B ,General Medicine ,Computer Science Applications ,Gene Expression Regulation, Neoplastic ,myofibroblast activation ,mitochondrial fusion ,030220 oncology & carcinogenesis ,Sirtuin ,Kidney Diseases ,Mitochondrial fission ,Signal Transduction ,SIRT3 ,extracellular matrix ,Article ,Lignans ,Catalysis ,Cell Line ,Transforming Growth Factor beta1 ,Inorganic Chemistry ,03 medical and health sciences ,Renal fibrosis ,Animals ,Humans ,Physical and Theoretical Chemistry ,Molecular Biology ,Inflammation ,urogenital system ,Biphenyl Compounds ,Organic Chemistry ,Fibrosis ,Disease Models, Animal ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,Mitochondrial biogenesis ,Tubulointerstitial fibrosis ,Cancer research ,biology.protein - Abstract
Renal fibrosis is a common feature of all progressive chronic kidney diseases. Sirtuin 3(SIRT3) is one of the mitochondrial sirtuins, and plays a role in the regulation of mitochondrialbiogenesis, oxidative stress, fatty acid metabolism, and aging. Recently, honokiol (HKL), as apharmaceutical SIRT3 activator, has been observed to have a protective effect against pressureoverload‐induced cardiac hypertrophy by increasing SIRT3 activity. In this study, we investigatedwhether HKL, as a SIRT3 activator, also has protective effects against unilateral ureteral obstruction(UUO)‐induced renal tubulointerstitial fibrosis through SIRT3‐dependent regulation ofmitochondrial dynamics and the nuclear factor‐&kappa, B (NF‐&kappa, B)/transforming growth factor‐&beta, 1 (TGF‐&beta, 1)/Smad signaling pathway. We found that HKL decreased the UUO‐induced increase in tubularinjury and extracellular matrix (ECM) deposition in mice. HKL also decreased myofibroblastactivation and proliferation in UUO kidneys and NRK‐49F cells. Finally, we showed that HKLtreatment decreased UUO‐induced mitochondrial fission and promoted mitochondrial fusionthrough SIRT3‐dependent effects. In conclusion, activation of SIRT3 via HKL treatment might havebeneficial effects on UUO‐induced renal fibrosis through SIRT3‐dependent regulation ofmitochondrial dynamics and the NF‐&kappa, B/TGF‐&beta, 1/Smad signaling pathway.
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- 2020
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36. SP284SERUM AND URINE LEVELS OF FATTY ACID BINDING PROTEIN 4 AND XCL1 CORRELATED WITH RENAL FUNCTION IN PATIENTS WITH DIABETIC CHRONIC KIDNEY DISEASE
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Jeong, Sang Ku, primary, Jong Hwan, Jung, additional, Woong, Park, additional, Kyung, Pyo Kang, additional, Sung, Kwang Park, additional, and Kim, Won, additional
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- 2019
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37. Kidney Transplant Patient with a Facial Redness
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Sik Lee, Jin Won Jang, Sung Kwang Park, Ja Yeon Lee, Hong Pil Hwang, Jin Han Lim, Hee Chul Yu, and Jong Hwan Jung
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Transplantation ,medicine.medical_specialty ,business.industry ,Incidence (epidemiology) ,Immunology ,Renal function ,urologic and male genital diseases ,medicine.disease ,Gastroenterology ,Surgery ,Malaise ,Lethargy ,Facial redness ,Internal medicine ,medicine ,medicine.symptom ,business ,Complication ,Kidney transplantation - Abstract
Posttransplant erythrocytosis (PTE) is a common complication of renal transplantation, which can occur in approximately 10% to 15% of renal transplant patients and usually affects males with relatively good renal function. It is also associated with an increased incidence of thromboembolic events. Clinical manifestations of PTE include malaise, headache, plethora, lethargy, and dizziness. It is correlated with use of cyclosporin, gender, posttransplant renal function, and type of antihypertensive medication. The angio- tensin receptor blocker (ARB) or angiotensin-converting enzyme inhibitor is preferred as an initial treatment for PTE because these agents are effective and reasonably safe in the majority of patients with PTE, and can also provide a necessary antihypertensive effect for kidney transplant patients. We report here on a 35-year-old male who had erythrocytosis after renal transplantation. After renal transplantation, his level of hemoglobin was 21 g/dL. We treated this patient with ARB and his symptoms and signs have been completely relieved.
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- 2015
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38. Evaluation of the clinical usefulness of modulated arc treatment
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Shin Wook Kim, Young Kyu Lee, Yeon Sil Kim, Hong Seok Jang, Hun Joo Shin, Sang Hee Nam, Young-Nam Kang, Hyeong Wook Park, Byung Ock Choi, Sung Kwang Park, Jae Choon Lee, Jin Young Kim, and Ji Na Kim
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Normal tissue ,FOS: Physical sciences ,General Physics and Astronomy ,Physics - Medical Physics ,Tomotherapy ,Conformity index ,Arc (geometry) ,Treatment plan ,medicine ,Medical physics ,Medical Physics (physics.med-ph) ,Homogeneity index - Abstract
The purpose of this study is to evaluate the clinical usefulness of modulated arc (mARC) treatment techniques. The mARC treatment plans of the non-small cell lung cancer (NSCLC) patients were performed in order to verify the clinical usefulness of mARC. A pre study was conducted to find the most competent plan condition of mARC treatment and the usefulness of mARC treatment plan was evaluated by comparing it with the other Arc treatment plans such as Tomotherapy and RapidArc. In the case of mARC, the optimal condition for the mARC plan was determined by comparing the dosimetric performance of the mARC plans with the use of various parameters. The various parameters includes the photon energies (6 MV, 10 MV), optimization point angle (6{\deg}-10{\deg} intervals), and total segment number (36-59 segment). The best dosimetric performance of mARC was observed at 10 MV photon energy and the point angle 6 degree, and 59 segments. The each treatment plans of three different techniques were compared with the following parameters: conformity index (CI), homogeneity index (HI), target coverage, dose in the OARs, monitor units (MU), beam on time and the normal tissue complication probability (NTCP). As a result, all three different treatment techniques show the similar target coverage. The mARC results the lowest V20 and MU per fraction compared with both RapidArc and Tomotherapy plan. The mARC plan reduces the beam on time as well. Therefore, the results of this study provided a satisfactory result which mARC technique is considered as a useful clinical technique for radiation treatment., Comment: 11 pages, 4 figures
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- 2015
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39. SIRT2 Regulates LPS-Induced Renal Tubular CXCL2 and CCL2 Expression
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Ae Sin Lee, Tung Nguyen-Thanh, Sung Kwang Park, Sik Lee, Dal Kim, Won Kim, Kyung Pyo Kang, and Yu Jin Jung
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Lipopolysaccharides ,Male ,MAPK/ERK pathway ,p38 mitogen-activated protein kinases ,Chemokine CXCL2 ,Down-Regulation ,Fluorescent Antibody Technique ,Biology ,SIRT2 ,Polymerase Chain Reaction ,Proinflammatory cytokine ,Kidney Tubules, Proximal ,Mice ,Random Allocation ,Sirtuin 2 ,medicine ,Animals ,Protein kinase A ,Cells, Cultured ,Chemokine CCL2 ,Mice, Knockout ,Analysis of Variance ,Kidney ,Kinase ,Epithelial Cells ,General Medicine ,Immunohistochemistry ,Disease Models, Animal ,Basic Research ,medicine.anatomical_structure ,Gene Expression Regulation ,Nephrology ,Cancer research ,NAD+ kinase ,Mitogen-Activated Protein Kinases - Abstract
Sirtuin 2 (SIRT2), a NAD(+)-dependent histone deacetylase, is involved in carcinogenesis and genomic instability and modulates proinflammatory immune responses. However, its role in renal inflammatory injury has not been demonstrated. In this study, we explored the expression patterns of CXCL2 and CCL2 in kidney tissue from Sirt2(-/-) and Sirt2(+/+) mice and in mouse proximal tubular epithelial (MPT) cells. CXCL2 and CCL2 were significantly downregulated at both the mRNA and the protein levels in kidneys of LPS-treated Sirt2(-/-) mice compared with those of LPS-treated Sirt2(+/+) mice. Furthermore, SIRT2 deficiency ameliorated LPS-induced infiltration of neutrophils and macrophages, acute tubular injury, and decrease of renal function. Supporting these observations, CXCL2 and CCL2 expression levels were lower in MPT cells treated with SIRT2-siRNA than in cells treated with control-siRNA, and adenovirus-mediated overexpression of SIRT2 in MPT cells significantly increased the LPS-induced expression of CXCL2 and CCL2 at the mRNA and protein levels. In addition, SIRT2 interacted with mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1), and SIRT2-knockdown increased the acetylation of MKP-1 and suppressed the phosphorylation of p38 MAPK and c-Jun N-terminal kinase in LPS-treated MPT cells. SIRT2 also regulated p65 binding to the promoters of CXCL2 and CCL2. Taken together, these findings indicate that SIRT2 is associated with expression of renal CXCL2 and CCL2 and that regulation of SIRT2 might be an important therapeutic target for renal inflammatory injury.
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- 2015
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40. Verification of light & radiation field coincidence quality assurance for radiation therapy by using a-Se based DR system
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Jeong-Eun Park, Ju-Yeon Hong, Eun-Tae Park, Kyo-Tae Kim, Won-Yong Oh, J. H. Kim, Heunglae Cho, Yunseon Choi, Tae-Suk Suh, Sunmi Jo, Ki-Jung Ahn, Jin-Young Kim, Seong-Jin Jin, Sung-Kwang Park, Hyun-Jung Kim, Jina Kim, Woong Cho, and Kyung-Min Oh
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Physics ,business.industry ,medicine.medical_treatment ,Radiation field ,Detector ,General Physics and Astronomy ,Radiation ,Coincidence ,Particle detector ,Radiation therapy ,Optics ,medicine ,business ,Quality assurance ,Light field - Abstract
Currently, the American Association of Physicists in Medicine (AAPM) recommends measuring the surface field size once a week by using an analog film in order to verify light and radiation field coincidence in the Quality Assurance (QA) of radiotherapy. However, the use of the film does not allow for a quantitative method of evaluation, and measuring the light field with radiation field detectors in a 2D array is difficult. Therefore, we used an amorphous-Se (a-Se) digital radiation detection system to measure the light and radiation fields simultaneously for a quantitative QA system, and the feasibility of using such a system was confirmed by ensuring the coincidence of the light and the radiation field measurements. The characteristics of the analog film and the a-Se digital radiation detection system were compared by delivering to each doses of 100, 10 monitor units(MU) of radiation at a rate of 400 MU/min to a radiation field 100 × 100 mm2 in size from a 100 cm source-surface distance (SSD). A 0.5 mm to 0.6 mm difference was measured in the X-axis, and a 0.3 mm difference was measured in the Y-axis. The difference in the measurements of the coincidence of light and the radiation field was less than 0.3 mm, which is relatively insignificant. These results indicate that the use of an a-Se digital radiation detection system is adequate for quality assurance of radiotherapy using light and radiation field coincidence. In addition, the experiment is considered to have provided valuable results in that the a-Se based digital radiation detection system enables simple and accurate QA for clinical radiation therapy by assessing the coincidence in the alignment of the light and the radiation fields.
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- 2015
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41. Clinical assessment of the jaw-tracking function in IMRT for a brain tumor
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Young-Kyu Lee, Gyu-Seok Cho, Tae-Suk Suh, Jung-Ki Kim, Sunmi Jo, Jin-Young Kim, Sung-Kwang Park, Sang-Hee Nam, Bo-Young Choe, Jung-Wook Shin, Shin-Wook Kim, Jin-Beom Chung, and Won-Yong Oh
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medicine.medical_specialty ,Cumulative dose ,business.industry ,medicine.medical_treatment ,Truebeam ,Brain tumor ,General Physics and Astronomy ,Dose profile ,Collimator ,medicine.disease ,law.invention ,Radiation therapy ,law ,medicine ,Jaw tracking ,Medical physics ,Radiation treatment planning ,Nuclear medicine ,business - Abstract
Intensity-modulated radiotherapy (IMRT) improves dose conformity and saves critical organs. IMRT is widely used in cases of head and neck, prostate, and brain cancer due to the close location of the targets to critical structures. However, because IMRT has a larger amount of radiation exposure than 3 dimensional-conformal radiation therapy (3D-CRT), it has disadvantages such as increases in the low dose irradiation to normal tissues and in the accumulated dose for the whole volume due to leakage and transmission of the multi-leaf collimator (MLC). The increased accumulated dose and the larger low dose may increase the occurrence of secondary malignant neoplasms. For these reasons, the jaw-tracking function of the TrueBeam (Varian Medical Systems, Palo Alto, CA) was developed to reduce the leakage and the transmission dose of the MLC with linear accelerators. However, the change in the superficial dose has not been verified with a quantitative analysis of the dose reduction in a brain tumor. Therefore, in the present study, we intended to verify the clinical possibility of utilizing the jaw-tracking function for a brain tumor by comparing treatment plans and superficial doses. To accomplish this, we made three types of original treatment plans using Eclipse11 (Varian Medical Systems, Palo Alto, CA): 1) farther than 2 cm from the organs at risk (OAR); 2) within 2 cm of the OAR; and 3) intersecting with the OAR. Jaw-tracking treatment plans were also made with copies of the original treatment plan using Smart LMC Version 11.0.31 (Varian Medical Systems, Palo Alto, CA). A comparison between the original treatment plans and jaw-tracking treatment plans was performed using the difference of the mean dose and maximum dose to the OARs in cumulative Dose Volume Histogram (DVH). In addition, the dependencies of the effects of transmission and the scattering doses according to jaw motion were assessed through the difference in the surface doses. In the DVH comparison, a maximum dose difference of 0.4% was observed between the planning methods in the case of over 2 cm distance, and the maximum dose of 0.6% was obtained for within the 2 cm distance. For the case intersecting with the OAR, the maximum dose difference of 2.3% was achieved. According to these results, the differences in the mean doses and the maximum doses to the OARs ware larger when the OARs and the planning target volume (PTV) were closer. In addition, small differences in the surface dose measurements were observed. In the case of the inside field, the differences were under 2% of the prescription dose while the difference was under 0.1% in the case of the outside field. Therefore, treatment plans with the jaw-tracking function consistently affected the dose reduction for a brain tumor, and the clinical possibility could be verified as the surface dose was not increased.
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- 2015
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42. Inhibition of histone deacetylase 1 ameliorates renal tubulointerstitial fibrosis via modulation of inflammation and extracellular matrix gene transcription in mice
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Tung Nguyen-Thanh, Won Kim, Dal Kim, Kyung Pyo Kang, Sung Kwang Park, and Sik Lee
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0301 basic medicine ,extracellular matrix ,kidney fibrosis ,030232 urology & nephrology ,Histone Deacetylase 1 ,Biology ,Kidney ,urologic and male genital diseases ,fibroblast ,Chromatin remodeling ,Transforming Growth Factor beta1 ,Extracellular matrix ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,Renal fibrosis ,Animals ,Humans ,Myofibroblasts ,Histone H3 acetylation ,histone deacetylase inhibitor ,Cell Proliferation ,Inflammation ,Extracellular Matrix Proteins ,urogenital system ,Valproic Acid ,Articles ,General Medicine ,Fibrosis ,HDAC1 ,Histone Deacetylase Inhibitors ,Kidney Tubules ,030104 developmental biology ,Cancer research ,Tubulointerstitial fibrosis ,lipids (amino acids, peptides, and proteins) ,Histone deacetylase ,Myofibroblast ,Signal Transduction ,Ureteral Obstruction - Abstract
Renal tubulointerstitial fibrosis is characterized by sustained inflammation and excessive extracellular matrix (ECM) accumulation, leading to chronic kidney disease. Valproic acid (VPA) has anticancer activity through regulation of cell differentiation and apoptosis via inhibition of histone deacetylase (HDAC) activity and is considered a class I HDAC inhibitor. In this study, the effect of VPA on unilateral ureteral obstruction (UUO)-induced renal fibrosis by modulation of renal inflammation and ECM gene transcription was investigated. VPA treatment increased histone H3 acetylation in both sham- and UUO-operated kidneys and decreased the UUO-induced increase in tubular injury and ECM deposition in mice. VPA also decreased myofibroblast activation and proliferation in UUO kidneys and NRK-49F cells. Finally, it was demonstrated that the anti-fibrotic effect of VPA was associated with regulation of ECM protein promoter enrichment at an acetylated histone H3 site. In conclusion, the findings indicate that VPA may have a beneficial effect on UUO-induced renal fibrosis via regulation of myofibroblast activation, proliferation, and ECM protein production by chromatin remodeling and ECM protein promoter transcription.
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- 2017
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43. Feasibility study of an optically-stimulated luminescent nanodot dosimeter (OSLnD) in high-energy photon beams
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JongEon Kim, Won-Young Oh, Sung-Kwang Park, Byung-In Min, Sang-Hee Nam, Kyoungmin Oh, Tae-Suk Suh, Jung-Wook Shin, Sunmi Jo, Jin-Young Kim, and Yon-Lae Kim
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medicine.medical_specialty ,Dosimeter ,Materials science ,business.industry ,General Physics and Astronomy ,Intensity (physics) ,Semiconductor ,medicine ,Optoelectronics ,Dosimetry ,Medical physics ,Field-effect transistor ,Nanodot ,Irradiation ,business ,Diode - Abstract
In-vivo dosimetry is essential to verify the position and the intensity of the radiation therapy, such as cranio-spinal irradiation (CSI) and total body irradiation (TBI). Various kinds of devices, such as a thermo-luminesence dosimeters (TLDs), metal-oxide semiconductor field effect transistors (MOSFETs), semiconductor diodes, and gafchromic films, are used in in-vivo dosimetry, and these have their respective pros and cons. An optically-stimulated luminescent nanodot dosimeter (OSLnD) made of Al2O3: C was developed to measure the radiation dose during diagnostics, but it is now used for clinical purposes. In this study, the characteristics of the OSLnD, such as its dose rate dependency, dose linearity, angular dependency, and field junction, were investigated under a 6 MV X-ray beam. The OSLnD showed a linear response at doses from 20 to 300 cGy in the dose linearity test. Also, the dose rate dependency was shown to be less than 3%, angular dependency to be less than 2%. The experimental results proved the OSLnD to be useful for measurements of the external dose and for intensity modulated radiotherapy (IMRT) in clinical radiotherapy.
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- 2014
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44. Analysis of Biologically Equivalent Dose of Stereotactic Body Radiotherapy for Primary and Metastatic Lung Tumors
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Heunglae Cho, Sang-Hwa Urm, and Sung-Kwang Park
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Cancer Research ,Pathology ,medicine.medical_specialty ,Lung ,Stereotactic body radiotherapy ,business.industry ,Equivalent dose ,Neoplasm metastasis ,Rate control ,medicine.disease ,Primary tumor ,Biologically effective dose ,medicine.anatomical_structure ,Oncology ,medicine ,Original Article ,Lung tumor ,Lung cancer ,Nuclear medicine ,business ,Small tumors - Abstract
Purpose The purpose of this study was to determine the optimal biologically equivalent dose (BED) for stereotactic body radiotherapy (SBRT) by comparing local control rates in proportion to various total doses and fractionation schedules. Materials and Methods Thirty-four patients with early non-small-cell lung cancer and a single metastatic lung tumor were included in this study. Differences in local control rates were evaluated according to gender, primary tumor site, response, tumor size, and BED. For comparison of BEDs, the prescribed dose for SBRT was stratified according to three groups: high (BED > 146 Gy), medium to high (BED, 106 to 146 Gy), and low to medium (BED < 106 Gy). Results For all patients, the overall local control rate was 85.3% at two years after treatment. Five local recurrences were observed, and, notably, all of them were observed in the low to medium BED group. Significantly higher local control rates were observed for patients with a complete response than for those with a partial response or stable disease (p < 0.001). Twenty-six patients with a tumor size of < 3 cm showed no dose-response relationship in the low to medium, medium to high, and high BED groups, whereas eight patients with a tumor size of ≥ 3 cm showed a significant dose-response relationship. The observed 2-year local recurrence-free survival rates in patients with a tumor size of < 3 cm and in those with a tumor size of ≥ 3 cm were 96.2% and 50.0%, respectively, which were significantly different (p=0.007). Conclusion BED > 100 Gy is required in order to achieve a > 85% local control rate regardless of tumor size. The optimal dose for small tumors of < 3 cm appears to be within a range below 150 Gy BED. Escalation of BED to high levels (> 150 Gy) may be required for patients with a tumor size larger than 3 cm.
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- 2014
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45. Management and Evaluation Prior to Transplantation of Deceased Donor
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Jong Hwan Jung, Sung Kwang Park, and Sik Lee
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Transplantation ,Deceased donor ,medicine.medical_specialty ,business.industry ,Immunology ,Treatment options ,Economic shortage ,medicine.disease ,Intensive care unit ,Organ transplantation ,law.invention ,End stage renal disease ,law ,Medicine ,business ,Intensive care medicine ,Kidney transplantation - Abstract
The number of people awaiting organ transplantation continues to exceed the number of organs available for transplantation, especially at a time when kidney transplantation is recognized as the best treatment option for end stage renal disease. There may be many reasons for this disparity of organ supply and demand, including the lack of consent, absence of an experienced coordinator team to help in closing the widening gap between organ supply and demand, and an unstandardized critical care management of potential organ donors. According to the report of the Korean Organ Transplant Registry in March 2014, due to a serious organ shortage in Korea, kidneys of deceased donors with low initial estimated glomerular filtration rate of
- Published
- 2014
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46. CELL SIGNALLING AND APOPTOSIS
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Won Kim, Kyung Pyo Kang, K.-U. Eckardt, Luigi Amoroso, Bernhard Aigner, Joahnnes Schödel, Gianfranco Tramonti, Mirian A. Boim, Clay Winterford, Krisztina Fazekas, Kyoung Hee Yang, Takeshi Nakanishi, Kyrill S. Rogacev, Mario Bonomini, Florian Thilo, Mirko Pesce, Eric Seibert, Sudipta Sinnya, Eun Hui Bae, Mutsuki Kawabe, Nuria Troyano Suárez, Joo Mi Lee, Paloma Martin, Robert P. Carroll, Javier Zamora, Sayuri Tanaka, Chao Wen Cheng, Jae Won Yang, Gabor Kokeny, Sara Franceschelli, Steffen Grampp, Yasuyuki Nagasawa, Sun Woo Kang, Adam M. Zawada, Jae Seok Kim, Karen M. Lyons, Jun Lv, Alzbeta Chorvatova, Jesús Egido, Alberto Ortiz, Jose Luis Cano, Lucas L Falke, In Jin Kim, Maria Vanesa Perez-Gomez, Adrian Oksa, Beatriz Fernandez-Fernandez, Fang Su, Shozo Yano, Gunnar H. Heine, Elisabetta Chieli, Jai Won Chang, Byoung Geun Han, Inés Mora, Chung-Ze Wu, Chien-Te Lee, Martina Böo´´Si, Ruiming Chang, Elisabeth Kemter, Yukiko Hasuike, Andrew Leask, Soo Wan Kim, Su-Kil Park, Roel Goldschmeding, Takumi Yoshida, Shunji Shiohira, Alan G. Jardine, Seong Kwon Ma, Marcus A. Glomb, Aritoshi Kida, Chia-An Chou, Duncan Lambie, Martin Tepel, Antônio da Silva Novaes, Dal Kim, Pablo Cannata-Ortiz, Paolo Felaco, Peter Soyer, Christine E. Staatz, Bogusz Trojanowicz, Danilo Fliser, Laura Calleros, Urban Sester, Hwee-Yeong Ng, Johanna Hundsdorfer, Miki Nishida, Kosaku Nitta, Maria Dolores Sanchez-Niño, Ana Belen Sanz, Li Yan, Kathryn K. Stevens, Christudas Morais, Sayuri Hamahata, Won Seok Yang, Yu Jin Jung, Diana Medrano-Andres, Hidekazu Sugiura, Biyun Wang, Masayoshi Nanami, Yueh-Ting Lee, María Piedad Ruiz-Torres, Anna Wolf, Silke Markau, Fernanda Borges, Henrike Berger, Julia Carracedo, Taehee Kim, Toshitsugu Sugimoto, Lorenza Speranza, Chung Hee Baek, Seongmoon Ong, Christof Ulrich, Viera Spustova, Scott B. Campbell, Shanying Liu, Jang Won Seo, Li-Cheng Chang, Su-Kil Seo, Felix Kohler, Antonia Patruno, Michael Burke, Alicia Luengo-Rodríguez, Vittorio Sirolli, Chang Seong Kim, Rafael Ramirez-Chamond, Sang Koo Lee, Mirjana Mijuskovic, Ken Tsuchiya, Roman Fiedler, Rafael Selgas, Tri Q. Nguyen, Miklos Mozes, Yeong-Hoon Kim, Nam Jeong Han, Christian Delles, Nicole M. Isbel, Ae Sin Lee, Andrea García-Jerez, Hideki Ohyama, Jonay Poveda, Dusan Chorvat, Dianne Z. Hillyard, Margarete Goppelt-Strübe, Nadia Romiti, Seung Ok Choi, Mana Yahiro, Kimberley Oliver, Ruediger Wanke, Mercedes Griera, Keiji Nakasho, Sik Lee, Takahiro Kuragano, Weiwen Liang, László Rosivall, Jin-Shuen Chen, Diego Rodríguez-Puyol, Sung Kwang Park, Eunhui Bae, Andreas Zakrzewicz, Matthias Girndt, Gema Olmos Centenero, Ingrid Lajdova, and Hyun Woo Kim
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Transplantation ,Cell signaling ,Nephrology ,Apoptosis ,business.industry ,Medicine ,business ,Cell biology - Published
- 2014
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47. OC-0050: Clinical significance of soluble PD-L1 level in hepatocellular carcinoma patients treated with RT
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Hyungjin Kim, Kyoung Jin Kim, Jinsil Seong, and Sung-Kwang Park
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medicine.medical_specialty ,biology ,business.industry ,Hematology ,medicine.disease ,Gastroenterology ,Oncology ,Internal medicine ,PD-L1 ,Hepatocellular carcinoma ,medicine ,biology.protein ,Radiology, Nuclear Medicine and imaging ,Clinical significance ,business - Published
- 2018
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48. Sirtuin 3 Activation by Honokiol Decreases Unilateral Ureteral Obstruction-Induced Renal Inflammation and Fibrosis via Regulation of Mitochondrial Dynamics and the Renal NF-κB-TGF-β1/Smad Signaling Pathway.
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Yi Quan, Woong Park, Jixiu Jin, Won Kim, Sung Kwang Park, and Kyung Pyo Kang
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RENAL fibrosis ,SIRTUINS ,TRANSFORMING growth factors-beta ,CHRONIC kidney failure ,URETERIC obstruction ,CARDIAC hypertrophy - Abstract
Renal fibrosis is a common feature of all progressive chronic kidney diseases. Sirtuin 3 (SIRT3) is one of the mitochondrial sirtuins, and plays a role in the regulation of mitochondrial biogenesis, oxidative stress, fatty acid metabolism, and aging. Recently, honokiol (HKL), as a pharmaceutical SIRT3 activator, has been observed to have a protective effect against pressure overload-induced cardiac hypertrophy by increasing SIRT3 activity. In this study, we investigated whether HKL, as a SIRT3 activator, also has protective effects against unilateral ureteral obstruction (UUO)-induced renal tubulointerstitial fibrosis through SIRT3-dependent regulation of mitochondrial dynamics and the nuclear factor-κB (NF-κB)/transforming growth factor-β1 (TGF-β1)/Smad signaling pathway. We found that HKL decreased the UUO-induced increase in tubular injury and extracellular matrix (ECM) deposition in mice. HKL also decreased myofibroblast activation and proliferation in UUO kidneys and NRK-49F cells. Finally, we showed that HKL treatment decreased UUO-induced mitochondrial fission and promoted mitochondrial fusion through SIRT3-dependent effects. In conclusion, activation of SIRT3 via HKL treatment might have beneficial effects on UUO-induced renal fibrosis through SIRT3-dependent regulation of mitochondrial dynamics and the NF-κB/TGF-β1/Smad signaling pathway. [ABSTRACT FROM AUTHOR]
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- 2020
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49. Evaluation of the Korean Network for Organ Sharing Expanded Donor Criteria in Deceased Donor Renal Transplantation
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Ui Jun Park, Suk Joo Park, Chan-Duck Kim, Sung Kwang Park, Ho Kyun Lee, Sang Young Chung, Soo Jin Choi, Young Hoon Kim, Hyoung Tae Kim, Sik Lee, Yong-Lim Kim, Won Hyun Cho, Hee Chul Yu, Jang-Hee Cho, and Min Young Kim
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Transplantation ,medicine.medical_specialty ,Deceased donor ,business.industry ,Family medicine ,Immunology ,medicine ,University medical ,medicine.disease ,business ,University hospital ,Kidney transplantation - Abstract
Ui Jun Park, M.D., Won Hyun Cho, M.D., Hyoung Tae Kim, M.D., Min Young Kim, R.N., Yong-Lim Kim, M.D., Chan-Duck Kim, M.D., Jang-Hee Cho, M.D., Young Hoon Kim, M.D., Suk Joo Park, M.D., Sang Young Chung, M.D., Soo Jin Na Choi, M.D., Ho Kyun Lee, M.D., Sung Kwang Park, M.D., Sik Lee, M.D. and Hee Chul Yu, M.D. Department of Surgery, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Department of Internal Medicine, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Department of Internal Medicine, Inje University Busan Paik Hospital, Inje University College of Medicine, Busan, Department of Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Department of Internal Medicine, Surgery, Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
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- 2013
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50. Metformin decreases high-fat diet-induced renal injury by regulating the expression of adipokines and the renal AMP-activated protein kinase/acetyl-CoA carboxylase pathway in mice
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Won Kim, Byung-Hyun Park, Sung Kwang Park, Jung Eun Lee, Dal Kim, Suhn Hee Kim, Ae Sin Lee, Sik Lee, Yu Jin Jung, and Kyung Pyo Kang
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Male ,medicine.medical_specialty ,Mice, Obese ,Adipokine ,AMP-Activated Protein Kinases ,Diet, High-Fat ,Kidney ,Transforming Growth Factor beta1 ,Mice ,Insulin resistance ,Adipokines ,AMP-activated protein kinase ,Internal medicine ,Glucose Intolerance ,Genetics ,medicine ,Animals ,Inflammation ,biology ,Podocytes ,digestive, oral, and skin physiology ,nutritional and metabolic diseases ,AMPK ,General Medicine ,medicine.disease ,Metformin ,Mice, Inbred C57BL ,Kidney Tubules ,Endocrinology ,medicine.anatomical_structure ,biology.protein ,Insulin Resistance ,Metabolic syndrome ,Steatohepatitis ,Oxidation-Reduction ,Acetyl-CoA Carboxylase ,Signal Transduction ,medicine.drug - Abstract
Metabolic syndrome is characterized by insulin resistance, dyslipidemia and hypertension. These metabolic changes contribute to the development of obesity-induced kidney injury. AMP-activated protein kinase (AMPK) is a ubiquitous enzyme that is involved in the cellular metabolic response to metabolic stress. Metformin, an AMPK activator, has been reported to exert a protective effect against non-alcoholic steatohepatitis. However, little is known about its role in the pathogenesis of obesity-induced renal injury. The aim of this study was to investigate the effects of metformin on high-fat diet (HFD)-induced kidney injury. Obesity was induced by HFD (60% of total calories from fat, 20% protein and 20% carbohydrates) in 6-week-old C57BL/6 mice. Mice were fed HFD plus 0.5% metformin. The effects of metformin on HFD-induced renal injury were evaluated by determining metabolic parameters, serum adipokine levels and renal AMPK/acetyl-CoA carboxylase (ACC) activities, as well as a histological examination. HFD induced metabolic derangement, systemic insulin resistance and glomerular mesangial matrix expansion. The administration of metformin reduced HFD-induced metabolic derangement and renal injury. The administration of metformin reduced the HFD-induced increase in adipokine expression and macrophage infiltration. Moreover, renal AMPK activity, which was decreased by HFD, was recovered following the administration of metformin; in addition, fatty acid oxidation was increased by the inhibition of ACC. These results indicate that metformin exerts beneficial effects on obesity-induced renal injury by regulating systemic inflammation, insulin resistance and the renal AMPK/ACC pathway. The clinical application of metformin to obese or early diabetic patients may be helpful in preventing obesity- or diabetes-related kidney disease.
- Published
- 2013
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