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Ratanasereeprasert N, Hsu LF, Wang SK, Chen YJ, Chang JH, Yao CCJ. Molecular signaling and mechanisms of low-level laser-induced gene expression in cells involved in orthodontic tooth movement. J Formos Med Assoc 2024; 123:442-451. [PMID: 37805307 DOI: 10.1016/j.jfma.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/03/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023] Open
Abstract
BACKGROUND The study aimed to observe molecular signaling, including reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm), to evaluate the alteration of gene expression by low-level laser therapy (LLLT) and the correlation between its mechanisms and the NF-kB pathway in cells involved in orthodontic tooth movement. METHODS Osteoblast-like cells (MG63), immortalized periodontal ligament cells (iPDL), and M1 macrophage-like cells were irradiated by 980-nm LLLT with energy densities of 1 and 10 J/cm2 ΔΨm and intracellular ROS were monitored using fluorescent probes. The changes of mRNA expression were assessed using reverse transcription polymerase chain reaction (RT-PCR). NF-kB inhibitor, ROS scavenger, and ΔΨm suppressor were used to analyze signals associated with the regulation of gene expression. Finally, Western blot analysis was performed to confirm NF-kB signaling after LLLT. RESULTS We found the increases of ΔΨm and ROS in all three cell types after LLLT, but no significant difference was observed between 1 and 10 J/cm2 LLLT. Regarding gene expression, some target genes were upregulated in MG63 6 h, 12 h, and 1 day after LLLT and in iPDL cells 12 h and 1 day after LLLT. However, no changes occurred in M1 cells. The inhibitor that significantly reduced most changes in gene expression was NF-kB inhibitor. Western blot analysis showed the increase in p-IkBα level after LLLT in iPDL and MG63, but not in M1. CONCLUSION The 980-nm LLLT increased ΔΨm and ROS production in all three cell types. However, changes in gene regulation were found only in MG63 and iPDL cells, which related to the NF-kB pathway.
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Affiliation(s)
| | - Li-Fang Hsu
- Department of Dentistry, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Shih-Kai Wang
- Department of Dentistry, School of Dentistry, National Taiwan University, Department of Pediatric Dentistry, National Taiwan University Children's Hospital, Taipei, Taiwan
| | - Yi-Jane Chen
- Graduate Institute of Clinical Dentistry, School of Dentistry, National Taiwan University, Taipei, Taiwan; Division of Orthodontics and Dentofacial Orthopedics, Dental Department, National Taiwan University Hospital, Taipei, Taiwan
| | - Jui-Heng Chang
- Graduate Institute of Clinical Dentistry, School of Dentistry, National Taiwan University, Taipei, Taiwan
| | - Chung-Chen Jane Yao
- Graduate Institute of Clinical Dentistry, School of Dentistry, National Taiwan University, Taipei, Taiwan; Division of Orthodontics and Dentofacial Orthopedics, Dental Department, National Taiwan University Hospital, Taipei, Taiwan.
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Hoang T, Sutera P, Nguyen T, Chang JH, Jagtap S, Song Y, Shetty A, Chowdhury DD, Chan A, Carrieri FAA, Song D, DeWeese TL, Lafargue A, Van der Eecken K, Bunz F, Ost P, Tran PT, Deek MP. The Impact of TP53 Mutations and Use of the TP53-Mutation-Reactivating Agent APR-246 on Metastatic Castrate-Sensitive Prostate Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e443. [PMID: 37785435 DOI: 10.1016/j.ijrobp.2023.06.1621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) TP53 mutations appear to be enriched over the spectrum of metastatic castration-sensitive prostate cancer (mCSPC) and are associated with worse survival outcomes. We chose to further explore the impact of dominant negative (DN) TP53 mutations on mCSPC progression and pro-metastatic behaviors in addition to studying the ability of APR-246, a small molecule targeting TP53 mutants, to blunt pro-metastatic behaviors. MATERIALS/METHODS We retrospectively analyzed 531 mCSPC patients who underwent next-generation sequencing. Patients were stratified by metastasis timing (synchronous if metastasis present at diagnosis or metachronous if arising after definitive treatment of localized disease) and the number of metastatic lesions (oligometastatic ≤5 or polymetastatic >5 lesions). Tumors were classified based on TP53 mutation status (missense, truncating, or wild-type [WT]) and dominant negativity, which was defined as the production of a mutant protein that reduces the residual WT protein's transcriptional activity according to the World Health Organization TP53 database. Clinical outcomes were radiographic progression-free survival (rPFS) and overall survival (OS), evaluated with Kaplan-Meier and multivariable Cox regression. To verify the impact of TP53 mutation on metastasis, we created isogenic 22Rv1 prostate cancer cell lines that carried either TP53 WT or TP53 R175H and tested this mutation for migration, invasion, and anchorage-independent growth. APR-246 (25-80 µM) was tested for anti-metastatic properties in vitro and anti-tumor growth in 22Rv1 xenografted nude mice. RESULTS In our cohort, 155 (29.2%) had a TP53 mutation, which mostly occurred in the DNA-binding domain (85.16%). DN TP53 mutations were associated with more aggressive disease states: DN TP53 mutations were enriched in patients with synchronous (vs. metachronous: 20.7% vs. 6.3%, p < 0.01) and polymetastatic disease (vs. oligometastatic: 14.4% vs. 7.9%, p < 0.01). On multivariable analysis, DN TP53 mutations were correlated with shorter rPFS (HR = 1.97, 95% CI: 1.31-2.98, p < 0.01) and OS (HR = 2.05, 95% CI: 1.14-3.68, p = 0.02) compared to those with TP53 WT. In vitro, 22Rv1 cells with DN TP53 R175H mutation had increased abilities to migrate, invade, and form colonies compared to TP53 WT. APR-246 treatment of TP53 R175H mutants blunted the pro-metastatic effects of the cell line in vitro (p < 0.01 for all assays by unpaired t-test). Interestingly, APR-246 also inhibited xenograft tumor growth of 22Rv1 TP53 R175H mutants (p < 0.0001 by two-way ANOVA). CONCLUSION DN TP53 mutations were associated with poorer survival outcomes for mCSPC patients. DN TP53 mutations also promoted prostate cancer pro-metastatic behaviors in vitro, which was effectively counteracted by APR-246, making it a promising treatment option that should be explored further in early-phase clinical studies.
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Affiliation(s)
- T Hoang
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - P Sutera
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - T Nguyen
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - J H Chang
- University of Maryland, Baltimore, MD
| | - S Jagtap
- University of Maryland, Baltimore, MD
| | - Y Song
- University of Maryland, Baltimore, MD
| | - A Shetty
- University of Maryland, Baltimore, MD
| | | | - A Chan
- University of Maryland, Baltimore, MD
| | | | - D Song
- Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Baltimore, MD
| | - T L DeWeese
- Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Baltimore, MD
| | - A Lafargue
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD
| | | | - F Bunz
- Johns Hopkins Medicine, Baltimore, MD, United States
| | - P Ost
- Department of Radiation Oncology, Ghent University Hospital, Ghent, Belgium
| | - P T Tran
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD; Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD
| | - M P Deek
- Rutgers Cancer Institute of New Jersey, Department of Radiation Oncology, New Brunswick, NJ
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Choi H, Kang HC, Chie EK, Chang JH, Jang BS. Whole Regional Lymph Node Area Delineation with Deep Learning Model for Total Marrow and Lymphoid Irradiation. Int J Radiat Oncol Biol Phys 2023; 117:e461-e462. [PMID: 37785476 DOI: 10.1016/j.ijrobp.2023.06.1659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Total body irradiation (TBI) has been performed for conditioning before hematopoietic stem cell transplantation. However, TBI can be related to diverse adverse events including radiation pneumonitis and cataract. Efforts to reduce these events include the total marrow irradiation (TMI) and total marrow and lymphoid irradiation (TMLI). Compared to TMI, TMLI requires more target delineations with lymph nodes which can be labor-intensive and time-consuming. However, with the TMI plans, the coverage to lymph node might be lower than TMLI and its clinical significance is unknown. In the current study, we aimed to develop a deep learning model for automatic delineation of whole regional lymph nodes area and assess the dose coverage of lymph nodes with TMI plans. MATERIALS/METHODS Whole regional lymph nodes (cervical, axillary, mediastinal, para-aortic, common iliac, external iliac, internal iliac, obturator, presacral, inguinal lymph nodes) were manually contoured by 3 radiation oncologists in 26 patients having whole body computed tomography (CT) images. Twenty patients were designated as the training/validation set and 6 patients as the testing set, and model was developed using the 'nnUNET' framework. The trained model was evaluated with dice coefficient score (DCS), precision, and recall. In addition, dose coverage of the automatically or manually delineated lymph nodes in TMI plans was calculated. RESULTS The mean value of DCS, precision, and recall of the trained model was 0.76, 0.81, and 0.74, respectively. Dose parameters for manually delineated lymph nodes in previously treated TMI plans showed the mean value of V100% (the percentage of volume receiving 100% of the prescribed dose), V95%, and V90% to be 46.50%, 62.12%, and 73.68%, respectively. The highest V90% was observed in presacral (93.61%), axillary (90.40%), obturator (88.78%), and internal iliac lymph nodes (84.67%). In contrast, the lowest V90% was identified in inguinal (47.95%), cervical (61.69%), and para-aortic (65.75%) and external iliac lymph nodes (68.97%). For automatically delineated lymph nodes, the mean value of V100%, V95%, and V90% of TMI plan was 38.35%, 55.06%, and 67.84%, respectively. The difference with dose coverage of lymph node between delineated manually and automatically was not statistically significant. CONCLUSION Automatic delineation of lymph node using deep learning showed the potential to reduce the labor-intensive process of TMLI. When treated with TMI, the coverage of inguinal, cervical, para-aortic and external iliac lymph nodes was lower than expected.
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Affiliation(s)
- H Choi
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - H C Kang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - E K Chie
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - J H Chang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - B S Jang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
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Lee HI, Jang BS, Lee TH, Park JH, Chang JH, Chie EK. Relationships between Microbiome and Response to Neoadjuvant Chemoradiotherapy in Rectal Cancer. Int J Radiat Oncol Biol Phys 2023; 117:S105. [PMID: 37784278 DOI: 10.1016/j.ijrobp.2023.06.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Gut microbiome is known to be involved in antitumor immunotherapy and chemotherapy responses; however, few research has focused on the role of gut microbiome in the setting of concurrent chemoradiotherapy (CCRT). In this study, we investigated the tumor microbiome dynamics in patients undergoing neoadjuvant CCRT for locally advanced rectal cancer and sought to determine whether the diversity and composition of microbiome affect treatment response. MATERIALS/METHODS A total of 103 samples from 26 patients with locally advanced rectal cancer were collected and 16S ribosomal RNA amplicon sequencing was performed. All patients underwent neoadjuvant CCRT followed by surgical resection between 2008 and 2016. Samples were obtained from both tumor and normal rectal tissue at pre- and post-CCRT. According to the American Joint Committee on Cancer tumor regression grading (TRG) system, patients were divided into responders (TRG 0, 1) and non-responders (TRG 2, 3). We performed diversity, taxonomy, and network analyses to compare responders and non-responders. Then, we established the Bayesian network model to predict treatment response in patients with rectal cancer. RESULTS Overall, we detected 1260 microbial genera from 287 families, 132 orders, 56 classes, and 32 phyla in the bacteria kingdom. Between tumor and normal rectal tissues, there was no difference in microbial diversity and composition. On the other hand, there was a significant decrease in diversity and compositional alterations when comparing pre- and post-CCRT samples (all p<0.001). Ten patients (38.5%) were classified as responders and 16 patients (61.5%) were classified as non-responders. In both groups, CCRT significantly reduced microbial diversity and altered their composition, but it was more pronounced in non-responders. In taxonomic analysis of pre-CCRT samples, butyrate-producing bacteria were differentially enriched in responders. Meanwhile, in post-CCRT samples, opportunistic pathogen were overrepresented in non-responders. The network analysis revealed that butyrate-producing bacteria had strong interactions in responders, whereas opportunistic pathogen demonstrated strong interactions in non-responders (Pearson's coefficient>0.5). Finally, five microbes were selected as the optimal set for the response prediction model, which yielded an area under the curve value of 82.33%. CONCLUSION CCRT significantly changed the diversity and composition of microbiome, especially in non-responders. Several microbes might be related with treatment response. These findings highlight the potential of microbiome to play an important role as a biomarker in patients with rectal cancer. (NCT02533271).
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Affiliation(s)
- H I Lee
- Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - B S Jang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - T H Lee
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - J H Park
- Department of Pathology, SMG-SNU Boramae Medical Center, Seoul, Korea, Republic of (South) Korea
| | - J H Chang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - E K Chie
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
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Chang JH, Lin A, Singer L, Mohamad O, Chan J, Friesner I, Zack T, Ashraf-Ganjouei A, Boreta L, Gottschalk A, Braunstein SE, Park CC, Hong JC. Identifying Common Topics in Patient Portal Messages with Unsupervised Natural Language Processing. Int J Radiat Oncol Biol Phys 2023; 117:e460-e461. [PMID: 37785473 DOI: 10.1016/j.ijrobp.2023.06.1657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Patient portal messaging is an increasingly important form of communication between patients and medical providers. This has become particularly relevant in oncology, where patients undergo intense longitudinal treatments that require frequent communication regarding symptoms, appointments, and diagnostic results. The rise in the volume of these messages has significantly increased the workload of medical providers and consequent physician burn-out. Natural language processing (NLP), particularly transformer-based models, may offer an automated approach to characterize the content of patient messages and improve message triage and routing. In this study, we employed a state-of-the-art language model (Bidirectional Encoder Representations from Transformers; BERT) to identify data-derived categories of representative topics from real-world data thereby providing basic information to build an appropriate routing system. MATERIALS/METHODS Patient-generated portal messages sent to a messaging pool for a single institution radiation oncology department from 2014 to 2023 were extracted. BERTopic, an NLP-based topic modeling technique based on BERT was optimized for topic modeling of patient messages. Uniform Manifold Approximation and Projection (UMAP) was used to reduce dimensionality and visualize topic relationships across messages. The BERTopic-identified topic categories were subsequently labeled manually by one of the physician investigators. Differences of number of messages over time were assessed using t-tests. RESULTS A total of 47,492 messages were retrieved. The average number of messages per month from a single patient ranged from 1 to 18 (median 1.67, interquartile range 1.0-2.4). The total volume of patient messages showed a ten-fold increase over the study period, with 101 messages per month sent in 2014 and 999 messages per month in 2022 (p<0.001). BERTopic initially identified 35 topics whose relationships and degrees of overlap were visualized by UMAP. Due to physician-identified similarities, these topics were reduced into 13 categories. The most frequent topic category was messages about laboratory tests or imaging studies: 24.3%, followed by messages expressing appreciation: 18.9%, scheduling discussions: 15.6%, symptom-related messages: 11%, and treatment-related messages: 10.7%. CONCLUSION Patient portal messages sent to a single institution radiation oncology department have increased dramatically in volume since implementation, corresponding to a broader national trend. NLP successfully identified common subject themes across patient messages, many of which are related to scheduling. This presents potential opportunities to apply NLP to automate message routing in the future.
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Affiliation(s)
- J H Chang
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA; Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - A Lin
- University of California San Francisco, Department of Hematology and Oncology, San Francisco, CA
| | - L Singer
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA
| | - O Mohamad
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - J Chan
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - I Friesner
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA; University of California, San Francisco, Bakar Computational Health Sciences Institute, San Francisco, CA
| | - T Zack
- University of California San Francisco, San Francisco, CA
| | - A Ashraf-Ganjouei
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA; University of California, San Francisco, Bakar Computational Health Sciences Institute, San Francisco, CA
| | - L Boreta
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - A Gottschalk
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - S E Braunstein
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - C C Park
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - J C Hong
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA; University of California, San Francisco, Bakar Computational Health Sciences Institute, San Francisco, CA
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Park JB, Jang BS, Chang JH, Kim JH, Hong KY, Jin US, Chang H, Myung Y, Jeong JH, Heo CY, Kim IA, Shin KH. Impact of the New ESTRO-ACROP Target Volume Delineation Guideline on Breast-Related Complications after Implant-Based Reconstruction and Postmastectomy Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:e198. [PMID: 37784842 DOI: 10.1016/j.ijrobp.2023.06.1070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) recently updated a new target volume delineation guideline for postmastectomy radiotherapy (PMRT) after implant-based reconstruction. This study aimed whether this change has impact on breast-related complications. MATERIALS/METHODS We retrospectively reviewed patients who underwent PMRT after mastectomy with tissue expander or permanent implant insertion from 2016 to 2021. In total, 412 patients were included; 277 received RT by the new ESTRO-ACROP target delineation (ESTRO-T), and 135 received RT by conventional target delineation (CONV-T). The primary endpoint was comparison between the target groups of major breast-related complication, including infection, capsular contracture, deformity and necrosis requiring re-operation or re-hospitalization during follow-up after RT or delayed implant replacement. Complications were evaluated according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0., and capsular contracture was graded by the Baker Classification. RESULTS The median follow-up was 29.5 months (range, 0.3-76.8). The 1-, 2-, and 3-year incidence rates of major breast-related complication were 5.7%, 10.0%, and 11.6% in the ESTRO-T group, and 8.2%, 13.8%, and 14.7% in the CONV-T groups; it did not show a difference between the groups (P = 0.55). In multivariate analyses, target delineation is not significantly associated with the major complications (hazard ratio [HR] = 0.93; P = 0.83, Table 1). There was no significant difference between the ESTRO-T and CONV-T groups in the incidence of any breast-related complications (3-year cumulative incidence, 37.3% vs. 29.4%, respectively; P = 0.28). Symptomatic RT-induced pneumonitis rates were 2.7% in the ESTRO-T group (7 patients) and 2.2% in the CONV-T group (3 patients). Only one local recurrence event occurred in the ESTRO-T group, which was within the ESTRO-target volume. CONCLUSION Target volume delineation according to the new ESTRO-ACROP guideline did not reduce the risk of major or any breast-related complications. As the dosimetric benefits of heart and lung have been reported, further analyses with long-term follow-up are necessary to evaluate whether it could be connected to better clinical outcomes.
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Affiliation(s)
- J B Park
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - B S Jang
- Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - J H Chang
- University of California San Francisco, Department of Radiation Oncology, San Francisco, CA
| | - J H Kim
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - K Y Hong
- Department of Plastic and Reconstructive Surgery, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - U S Jin
- Department of Plastic and Reconstructive Surgery, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - H Chang
- 2nd Department of Plastic and Reconstructive Surgery, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - Y Myung
- Department of Plastic and Reconstructive Surgery, Seoul National University Bundang Hospital, Seongnam, Korea, Republic of (South) Korea
| | - J H Jeong
- Department of Plastic and Reconstructive Surgery, Seoul National University Bundang Hospital, Seongnam, Korea, Republic of (South) Korea
| | - C Y Heo
- Department of Plastic and Reconstructive Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea, Republic of (South) Korea
| | - I A Kim
- Department of Radiation Oncology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea, Republic of (South) Korea
| | - K H Shin
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
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Lee HI, Chang JH, Koh J, Cha MJ, Kim HJ. The Early and Late Effects of High-Dose Irradiation on Cardiac Injury in a Rat Model. Int J Radiat Oncol Biol Phys 2023; 117:e190. [PMID: 37784825 DOI: 10.1016/j.ijrobp.2023.06.1052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Radiation-induced heart disease is a critical concern after radiotherapy (RT) for thoracic and chest wall tumors; however, the biological effects and mechanisms are still unknown. In this study, we investigated dose-responsive functional and pathological changes in rat hearts at 1, 3, and 5 months after high-dose irradiation. Then, we sought to elucidate the underlying mechanisms of myocardial changes induced by high-dose irradiation. MATERIALS/METHODS Whole hearts of rats (N = 72) were irradiated with a single fraction of 0 (control), 10, 20, or 30 Gy and allocated into three groups according to the follow-up period after RT: baseline, one, three, and five months. During follow-up periods, rats underwent functional evaluation by electrocardiogram and echocardiography at 4-week intervals. If a rat's body weight decreased by 20% or more, it was considered premature death, and the heart was explanted immediately. Otherwise, all hearts were explanted when each group's follow-up period was completed. Pathological changes of cardiac structures were evaluated using a light microscope after staining with hematoxylin-eosin, Masson's trichrome, α-smooth muscle actin, desmin, and connexin-43. RESULTS All rats irradiated with 0 or 10 Gy completed their follow-up periods with continuously increasing body weight. However, among rats irradiated with 20 or 30 Gy, half of the rats died prematurely at 8-10 weeks after RT, and the remainder survived until 20 weeks. In echocardiography, increased wall thickness and E/E' ratio, and decreased end-diastolic volume were observed in 20-30 Gy groups compared to 0-10 Gy groups from 8 weeks after RT. Ejection fraction was preserved in all groups. In pathological review, 20-30 Gy groups demonstrated diffuse inflammation and vacuolization at 4 weeks. Then, at 8 weeks, prominent fibrotic changes and intercalated disc disruptions were observed. Notably, fibrotic changes were somewhat resolved at 20 weeks, but intercalated disc disruptions were not repaired until 20 weeks. The 0 and 10 Gy groups showed no significant changes in both functional and pathological analyses. CONCLUSION Rats irradiated with 20 or 30 Gy showed diastolic dysfunction in functional analysis and time-dependent myocardial changes in pathological analysis. Radiation-induced fibrosis might be a "reactive" fibrosis, which could proceed to either a profibrotic course (progressive fibrosis) or an anti-fibrotic course (recovery phase). Further studies are needed to identify whether high-dose irradiation-induced cardiac fibrosis could be reversible.
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Affiliation(s)
- H I Lee
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - J H Chang
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - J Koh
- Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - M J Cha
- Division of Cardiology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea, Republic of (South) Korea
| | - H J Kim
- Department of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea
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Ryu HJ, Shin KH, Chang JH, Jang BS. Pattern and Complication of Reconstructed Breast Cancer Patients Who Received Postmastectomy Radiotherapy in the National Health Insurance Service Cohort. Int J Radiat Oncol Biol Phys 2023; 117:S176-S177. [PMID: 37784437 DOI: 10.1016/j.ijrobp.2023.06.647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) This study aimed to analyze the nationwide pattern of reconstruction after mastectomy in patients with breast cancer who received postmastectomy radiotherapy (PMRT) and to compare complications according to fractionation and reconstruction procedures. MATERIALS/METHODS By using claim data from the National Health Insurance Service (NHIS) database, we analyzed breast cancer patients who received PMRT and underwent reconstruction between 2015 and 2020. We defined the grade ≥ 3 complications as the primary endpoint which involved hospital admission to the plastic surgery department. The complication was identified by using the procedure code for debridement and the International Classification of Diseases 10th codes for wound infections, dehiscence, necrosis, and mechanical complication of breast prosthesis and implant. The propensity score matching method was adopted to constitute the matched cohort between the hypofractionated fractionation (HF) and the conventional fractionation (CF), adjusted for age, diabetes, hypertension, obesity, smoking history, PMRT technique, use of bolus, year of PMRT delivery, and reconstruction method. Logistic regression was performed to evaluate the association between complication and variables. RESULTS Altogether 4,553 patients were analyzed: 1,395 (30.6%) in the HF group and 3,158 (69.4.%) in the CF group. The use of HF has steadily increased from 20.1% in 2015 to 42.2% in 2020. Immediate implant reconstruction (36.8%) method was the most frequently used, followed by immediate autologous (33.3%) and two-stage implant reconstruction methods (19.6%). In the matched cohort (N = 2,052), the major complication rate was not significantly different between the HF group and the CF group (5.9% [60/1,026] vs. 5.4% [55/1,026], P = 0.568) with the median follow-up of 30.9 months (range, 6.0-82.1). Surgical debridement was performed in 3.3% [34/1026] of the HF group and 3.5% [36/1026] of the CF group (P = 0.808). HF was not associated with major complications (odds ratio (OR) 1.09, 95% CI 0.75-1.59, P = 0.128). CONCLUSION In a nationwide insurance cohort, the complication rate was not significantly different between the HF group and the CF group. Our data suggest HF for reconstructed breasts is comparable to CF. However, consultation for fractionation regimen for reconstructed breast cancer patients may be still required at time of consideration of PMRT.
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Affiliation(s)
- H J Ryu
- Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea; Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - K H Shin
- Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea; Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - J H Chang
- Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea; Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
| | - B S Jang
- Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea, Republic of (South) Korea; Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea, Republic of (South) Korea
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Li GJ, Tan H, Nusrat H, Chen H, Chang JH, Shahi J, Poon I, Tsao M, Ung YC, Cheung P, Louie AV. Safety and Efficacy of Stereotactic Body Radiotherapy for Ultra-Central Thoracic Tumors. Int J Radiat Oncol Biol Phys 2023; 117:e35-e36. [PMID: 37785212 DOI: 10.1016/j.ijrobp.2023.06.725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiotherapy (SBRT) is increasingly utilized in the management of ultra-central thoracic tumors, although concerns regarding significant toxicity remain. We sought to evaluate the toxicity and efficacy of SBRT to these tumors at our institution. MATERIALS/METHODS Patients with ultra-central lung tumors or nodes treated at our institution with SBRT between 2009 and 2019 were retrospectively reviewed. Ultra-central was defined as having the planning target volume (PTV) overlapping or abutting the central bronchial tree and/or esophagus. All SBRT plans were generated with homogenous dose distributions using target coverage objectives of ITV V100% >99%, PTV V95% >99%, and an ideal PTV Dmax <105% (strict <120%). All plans were reviewed in quality assurance rounds by a team of dosimetrists, physicists, and radiation oncologists. The primary endpoint was incidence of severe toxicity (ST), defined as SBRT-related grade ≥3 toxicities, graded using the Common Terminology Criteria for Adverse Events V5.0. Secondary endpoints included local failure (LF), progression-free survival (PFS) and overall survival (OS). Competing risk analysis was used to estimate incidence and predictors of ST and LF, with death as a competing risk. Kaplan-Meier method was used to estimate PFS and OS. RESULTS A total of 154 patients who received 162 ultra-central courses of SBRT were included, with a median follow-up of 21.5 months. Treatment intent was most commonly for oligoprogression (46%), oligometastasis (30%), followed by curative (20%). The most frequent tumor histologies were NSCLC (41%) and RCC (26%). SBRT prescription doses ranged from 30-55 Gy in 5 fractions (BED10 range 48-115 Gy). The most common prescription was 50 Gy in 5 fractions (42%). The cumulative incidence of ST was 8.9% at 3-years. The most common ST was pneumonitis (n = 4). Notable toxicities included bronchopleural fistula (n = 2, grade 3 and 4), bronchial stricture (n = 1, grade 3), and esophagitis leading to bleeding (n = 1, grade 4). There were no esophageal strictures or perforations, and no bronchial bleeds. There was 1 possible treatment related death from pneumonitis/pneumonia. Predictors of any ST included increased lung V5 Gy, decreased PTV V95%, and not having prior radiation therapy to the chest. The cumulative incidence of LF was 4.8%, 11% and 14% at 1-, 2-, and 3-years respectively. Predictors of LF included younger age, and greater volume of overlap between the PTV and esophagus. Median PFS was 8.4 months, while median OS was 3.7 years. CONCLUSION In one of the largest case series of ultra-central thoracic SBRT reported to date, homogenously prescribed SBRT plans were associated with relatively low rates of ST and LF across a variety of treatment indications. Predictors of ST should be interpreted recognizing the heterogeneity in toxicities observed. Identified predictors of both ST and LF can contribute to future work to optimize the therapeutic ratio in treatment of ultra-central thoracic tumors.
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Affiliation(s)
- G J Li
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - H Tan
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - H Nusrat
- Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - H Chen
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - J H Chang
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - J Shahi
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - I Poon
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - M Tsao
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Y C Ung
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - P Cheung
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - A V Louie
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
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Park CJ, Han K, Kim H, Ahn SS, Choi D, Park YW, Chang JH, Kim SH, Cha S, Lee SK. MRI Features May Predict Molecular Features of Glioblastoma in Isocitrate Dehydrogenase Wild-Type Lower-Grade Gliomas. AJNR Am J Neuroradiol 2021; 42:448-456. [PMID: 33509914 DOI: 10.3174/ajnr.a6983] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 10/19/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND PURPOSE Isocitrate dehydrogenase (IDH) wild-type lower-grade gliomas (histologic grades II and III) with epidermal growth factor receptor (EGFR) amplification or telomerase reverse transcriptase (TERT) promoter mutation are reported to behave similar to glioblastoma. We aimed to evaluate whether MR imaging features could identify a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma. MATERIALS AND METHODS In this multi-institutional retrospective study, pathologically confirmed IDH wild-type lower-grade gliomas from 2 tertiary institutions and The Cancer Genome Atlas constituted the training set (institution 1 and The Cancer Genome Atlas, 64 patients) and the independent test set (institution 2, 57 patients). Preoperative MRIs were analyzed using the Visually AcceSAble Rembrandt Images and radiomics. The molecular glioblastoma status was determined on the basis of the presence of EGFR amplification and TERT promoter mutation. Molecular glioblastoma was present in 73.4% and 56.1% in the training and test sets, respectively. Models using clinical, Visually AcceSAble Rembrandt Images, and radiomic features were built to predict the molecular glioblastoma status in the training set; then they were validated in the test set. RESULTS In the test set, a model using both Visually AcceSAble Rembrandt Images and radiomic features showed superior predictive performance (area under the curve = 0.854) than that with only clinical features or Visually AcceSAble Rembrandt Images (areas under the curve = 0.514 and 0.648, respectively; P < . 001, both). When both Visually AcceSAble Rembrandt Images and radiomics were added to clinical features, the predictive performance significantly increased (areas under the curve = 0.514 versus 0.863, P < .001). CONCLUSIONS MR imaging features integrated with machine learning classifiers may predict a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.
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Affiliation(s)
- C J Park
- From the Department of Radiology (C.J.P.), Yonsei University College of Medicine, Seoul, Korea
| | - K Han
- Department of Radiology (K.H., H.K., S.S.A., Y.W.P., S.-K.L.), Research Institute of Radiological Sciences, Center for Clinical Imaging Data Science
| | - H Kim
- Department of Radiology (K.H., H.K., S.S.A., Y.W.P., S.-K.L.), Research Institute of Radiological Sciences, Center for Clinical Imaging Data Science
| | - S S Ahn
- Department of Radiology (K.H., H.K., S.S.A., Y.W.P., S.-K.L.), Research Institute of Radiological Sciences, Center for Clinical Imaging Data Science
| | - D Choi
- Department of Computer Science (D.C.), Yonsei University, Seoul, Korea
| | - Y W Park
- Department of Radiology (K.H., H.K., S.S.A., Y.W.P., S.-K.L.), Research Institute of Radiological Sciences, Center for Clinical Imaging Data Science
| | | | - S H Kim
- Department of Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | - S Cha
- Department of Radiology and Biomedical Imaging (S.C.), University of California San Francisco, San Francisco, California
| | - S-K Lee
- Department of Radiology (K.H., H.K., S.S.A., Y.W.P., S.-K.L.), Research Institute of Radiological Sciences, Center for Clinical Imaging Data Science
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Hwang IC, Kim AJ, Ro H, Jung JY, Chang JH, Lee HH, Chung W, Park YH. Changes in Bone Mineral Density After Kidney Transplantation. Transplant Proc 2018; 50:2506-2508. [PMID: 30316387 DOI: 10.1016/j.transproceed.2018.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/22/2018] [Accepted: 04/06/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND Numerous studies have shown that osteoporosis is common in kidney transplant recipients. However, the change in bone mineral density after kidney transplantation (KT) is not fully understood. METHODS Thirty-nine kidney transplant recipients with bone densitometry at pretransplant and 24 months after KT were reviewed. RESULTS The recipients' median age (44.5 ± 10.7 years) and dialysis duration before KT (4.2 ± 3.4 years) were recorded. The T-scores of the lumbar spine and femur neck at 24 months after KT were positively associated with the respective pretransplant T-score (P < .001 in the lumbar spine and P < .001 in the femur neck). However, the T-score after KT did not show significant change (P = .680 in lumbar spine, P = .093 in femur neck). Changes in the T-scores of the lumbar spine and femur neck over 24 months (delta T-score) were negatively associated with the respective pretransplant T-scores (P = .001 in lumbar spine, P = .026 in femur neck). Changes in the T-scores of the lumbar spine and femur neck over 24 months (delta T-score) were also associated with the pretransplant T-scores after the adjustment of other variables. CONCLUSION The change of bone mineral density was related with pretransplant bone mineral density. Careful follow-up of bone densitometry for KT recipients was needed.
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Affiliation(s)
- I C Hwang
- Department of Medicine, Gachon University College of Medicine, Inchon, Republic of Korea
| | - A J Kim
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea
| | - H Ro
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea.
| | - J Y Jung
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea
| | - J H Chang
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea
| | - H H Lee
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea
| | - W Chung
- Department of Internal Medicine, Gachon University Gil Medical Center, Inchon, Republic of Korea
| | - Y H Park
- Department of Surgery, Gachon University Gil Medical Center, Inchon, Republic of Korea
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Kim AJ, Ro H, Chang JH, Jung JY, Chung WK, Park YH, Lee HH. Suspected Frequent Relapsing IgG4-related Lung Disease in Kidney Transplant Patient: A Case Report. Transplant Proc 2018; 50:2572-2574. [PMID: 30316401 DOI: 10.1016/j.transproceed.2018.02.197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 02/19/2018] [Indexed: 12/21/2022]
Abstract
Besides the initial description of IgG4-related pancreatic disease, other sites are now commonly involved. However, occurrence of IgG4-related disease is rare in organ transplanted patients. A 57-year-old man who received a kidney transplantation presented with recurrent dyspnea on exertion. A computed tomography scan of the chest revealed bilateral interlobular septal thickening and multiple tubular and branching small nodular lesions in the right upper lobe, and mass-like consolidation of the left middle lobe. Despite no elevation of serum IgG4 level, a percutaneous core needle biopsy on consolidative mass showed interstitial fibrosis and infiltration of IgG4-positive plasma cells to be more than > 20 per high power field. After treatment with glucocorticoids and rituximab, the consolidative mass of the left middle lobe disappeared.
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Affiliation(s)
- A J Kim
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea
| | - H Ro
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea
| | - J H Chang
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea
| | - J Y Jung
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea
| | - W K Chung
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea
| | - Y H Park
- Department of Surgery, College of Medicine, Gachon University, Incheon, Korea
| | - H H Lee
- Department of Internal Medicine, College of Medicine, Gachon University, Incheon, Korea.
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Park YW, Han K, Ahn SS, Choi YS, Chang JH, Kim SH, Kang SG, Kim EH, Lee SK. Whole-Tumor Histogram and Texture Analyses of DTI for Evaluation of IDH1-Mutation and 1p/19q-Codeletion Status in World Health Organization Grade II Gliomas. AJNR Am J Neuroradiol 2018. [PMID: 29519794 DOI: 10.3174/ajnr.a5569] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Prediction of the isocitrate dehydrogenase 1 (IDH1)-mutation and 1p/19q-codeletion status of World Health Organization grade ll gliomas preoperatively may assist in predicting prognosis and planning treatment strategies. Our aim was to characterize the histogram and texture analyses of apparent diffusion coefficient and fractional anisotropy maps to determine IDH1-mutation and 1p/19q-codeletion status in World Health Organization grade II gliomas. MATERIALS AND METHODS Ninety-three patients with World Health Organization grade II gliomas with known IDH1-mutation and 1p/19q-codeletion status (18 IDH1 wild-type, 45 IDH1 mutant and no 1p/19q codeletion, 30 IDH1-mutant and 1p/19q codeleted tumors) underwent DTI. ROIs were drawn on every section of the T2-weighted images and transferred to the ADC and the fractional anisotropy maps to derive volume-based data of the entire tumor. Histogram and texture analyses were correlated with the IDH1-mutation and 1p/19q-codeletion status. The predictive powers of imaging features for IDH1 wild-type tumors and 1p/19q-codeletion status in IDH1-mutant subgroups were evaluated using the least absolute shrinkage and selection operator. RESULTS Various histogram and texture parameters differed significantly according to IDH1-mutation and 1p/19q-codeletion status. The skewness and energy of ADC, 10th and 25th percentiles, and correlation of fractional anisotropy were independent predictors of an IDH1 wild-type in the least absolute shrinkage and selection operator. The area under the receiver operating curve for the prediction model was 0.853. The skewness and cluster shade of ADC, energy, and correlation of fractional anisotropy were independent predictors of a 1p/19q codeletion in IDH1-mutant tumors in the least absolute shrinkage and selection operator. The area under the receiver operating curve was 0.807. CONCLUSIONS Whole-tumor histogram and texture features of the ADC and fractional anisotropy maps are useful for predicting the IDH1-mutation and 1p/19q-codeletion status in World Health Organization grade II gliomas.
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Affiliation(s)
- Y W Park
- From the Department of Radiology (Y.W.P.), Ewha Womans University College of Medicine, Seoul, Korea.,Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.S.A., Y.S.C., S.-K.L.)
| | - K Han
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.S.A., Y.S.C., S.-K.L.)
| | - S S Ahn
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.S.A., Y.S.C., S.-K.L.)
| | - Y S Choi
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.S.A., Y.S.C., S.-K.L.)
| | - J H Chang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | - S H Kim
- Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | - S-G Kang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | - E H Kim
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | - S-K Lee
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.S.A., Y.S.C., S.-K.L.)
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Park YW, Han K, Ahn SS, Bae S, Choi YS, Chang JH, Kim SH, Kang SG, Lee SK. Prediction of IDH1-Mutation and 1p/19q-Codeletion Status Using Preoperative MR Imaging Phenotypes in Lower Grade Gliomas. AJNR Am J Neuroradiol 2018; 39:37-42. [PMID: 29122763 DOI: 10.3174/ajnr.a5421] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/14/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE WHO grade II gliomas are divided into three classes: isocitrate dehydrogenase (IDH)-wildtype, IDH-mutant and no 1p/19q codeletion, and IDH-mutant and 1p/19q-codeleted. Different molecular subtypes have been reported to have prognostic differences and different chemosensitivity. Our aim was to evaluate the predictive value of imaging phenotypes assessed with the Visually AcceSAble Rembrandt Images lexicon for molecular classification of lower grade gliomas. MATERIALS AND METHODS MR imaging scans of 175 patients with lower grade gliomas with known IDH1 mutation and 1p/19q-codeletion status were included (78 grade II and 97 grade III) in the discovery set. MR imaging features were reviewed by using Visually AcceSAble Rembrandt Images (VASARI); their associations with molecular markers were assessed. The predictive power of imaging features for IDH1-wild type tumors was evaluated using the Least Absolute Shrinkage and Selection Operator. We tested the model in a validation set (40 subjects). RESULTS Various imaging features were significantly different according to IDH1 mutation. Nonlobar location, larger proportion of enhancing tumors, multifocal/multicentric distribution, and poor definition of nonenhancing margins were independent predictors of an IDH1 wild type according to the Least Absolute Shrinkage and Selection Operator. The areas under the curve for the prediction model were 0.859 and 0.778 in the discovery and validation sets, respectively. The IDH1-mutant, 1p/19q-codeleted group frequently had mixed/restricted diffusion characteristics and showed more pial invasion compared with the IDH1-mutant, no codeletion group. CONCLUSIONS Preoperative MR imaging phenotypes are different according to the molecular markers of lower grade gliomas, and they may be helpful in predicting the IDH1-mutation status.
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Affiliation(s)
- Y W Park
- From the Department of Radiology (Y.W.P.), Ewha Womans University College of Medicine, Seoul, Korea
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
| | - K Han
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
| | - S S Ahn
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
| | - S Bae
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
| | - Y S Choi
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
| | | | - S H Kim
- Pathology (S.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | | | - S-K Lee
- Departments of Radiology and Research Institute of Radiological Science (Y.W.P., K.H., S.-K.L., S.B., Y.S.C., S.S.A.)
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Choi YS, Ahn SS, Lee HJ, Chang JH, Kang SG, Kim EH, Kim SH, Lee SK. The Initial Area Under the Curve Derived from Dynamic Contrast-Enhanced MRI Improves Prognosis Prediction in Glioblastoma with Unmethylated MGMT Promoter. AJNR Am J Neuroradiol 2017. [PMID: 28642265 DOI: 10.3174/ajnr.a5265] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND PURPOSE Although perfusion and permeability MR parameters have known to have prognostic value, they have reproducibility issues. Our aim was to evaluate whether the initial area under the time-to-signal intensity curve (IAUC) derived from dynamic contrast-enhanced MR imaging can improve prognosis prediction in patients with glioblastoma with known MGMT status. MATERIALS AND METHODS We retrospectively examined 88 patients with glioblastoma who underwent preoperative dynamic contrast-enhanced MR imaging. The means of IAUC values at 30 and 60 seconds (IAUC30mean and IAUC60mean) were extracted from enhancing tumors. The prognostic values of IAUC parameters for overall survival and progression-free survival were assessed with log-rank tests, according to the MGMT status. Multivariate overall survival and progression-free survival models before and after adding the IAUC parameters as covariates were explored by net reclassification improvement after receiver operating characteristic analysis for 1.5-year overall survival and 1-year progression-free survival and by random survival forest. RESULTS High IAUC parameters were associated with worse overall survival and progression-free survival in the unmethylated MGMT group, but not in the methylated group. In the unmethylated MGMT group, 1.5-year overall survival and 1-year progression-free survival prediction improved significantly after adding IAUC parameters (overall survival area under the receiver operating characteristic curve, 0.86; progression-free survival area under the receiver operating characteristic curve, 0.74-0.76) to the model with other prognostic factors (overall survival area under the receiver operating characteristic curve, 0.81; progression-free survival area under the receiver operating characteristic curve, 0.69; P < .05 for all) except in the case of IAUC60mean for 1-year progression-free survival prediction (P = .059). Random survival forest models indicated that the IAUC parameters were the second or most important predictors in the unmethylated MGMT group, except in the case of the IAUC60mean for progression-free survival. CONCLUSIONS IAUC can be a useful prognostic imaging biomarker in patients with glioblastoma with known MGMT status, improving prediction of glioblastoma prognosis with the unmethylated MGMT promoter status.
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Affiliation(s)
- Y S Choi
- From the Department of Radiology and Research Institute of Radiological Science (Y.S.C., S.S.A., H.-J.L., S.-K.L.)
| | - S S Ahn
- From the Department of Radiology and Research Institute of Radiological Science (Y.S.C., S.S.A., H.-J.L., S.-K.L.)
| | - H-J Lee
- From the Department of Radiology and Research Institute of Radiological Science (Y.S.C., S.S.A., H.-J.L., S.-K.L.)
| | - J H Chang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | - S-G Kang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | - E H Kim
- Neurosurgery (J.H.C., S.-G.K., E.H.K.), Yonsei University College of Medicine, Seoul, Korea
| | - S H Kim
- Departments of Pathology (S.H.K.)
| | - S-K Lee
- From the Department of Radiology and Research Institute of Radiological Science (Y.S.C., S.S.A., H.-J.L., S.-K.L.)
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Lim JHL, Choo W, Chang JH, Tey HL, Chong WS. Application of iodinated starch powder using an atomizer spray gun - a new and effective tool to evaluate hypohidrosis. Skin Res Technol 2015; 22:370-4. [PMID: 26452436 DOI: 10.1111/srt.12275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2015] [Indexed: 11/29/2022]
Abstract
BACKGROUND Hypohidrosis is defined as diminished sweating in response to an appropriate thermal or sympathetic stimulus. When encountered in a clinical setting, it necessitates an accurate documentation of its pattern and extent to prognosticate the risk of associated heat-related illnesses. This can be achieved by thermoregulatory sweat testing which includes a starch-iodine sweat test that can be administered via various methods. OBJECTIVE To describe and evaluate the effectiveness and safety of a novel method of using an atomizer spray gun in administering the starch-iodine test. METHODS We describe the administration of the starch-iodine test via an atomizer spray gun (Series 700 Lab Model; Mitsuba Systems, Mumbai, India). The method was utilized for the evaluation of 30 individuals who presented with symptoms of hypohidrosis. RESULTS Application of iodinated starch powder prepared in-house with the atomizer spray gun achieved a lightweight and homogeneous coat on our patients' skin which allowed for clear visualization of the sweating pattern in areas of anhidrosis. The sharp demarcation of the pathological regions enabled the precise calculation of the affected body surface area of impaired sweating. Unlike the starch-iodine tests using the Minor and Wada methods, neither staining of the skin nor irritation was detected in this method. CONCLUSION We report a novel method of using an atomizer spray gun to perform the starch-iodine test in a rapid, reproducible, effective, and safe manner suitable for use in the clinical evaluation of hypohidrosis.
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Affiliation(s)
| | - W Choo
- National Skin Center, Singapore
| | | | - H L Tey
- National Skin Center, Singapore
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Jeon YK, Shin MJ, Kim MH, Mok JH, Kim SS, Kim BH, Kim SJ, Kim YK, Chang JH, Shin YB, Kim IJ. Low pulmonary function is related with a high risk of sarcopenia in community-dwelling older adults: the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011. Osteoporos Int 2015; 26:2423-9. [PMID: 25956284 DOI: 10.1007/s00198-015-3152-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 04/26/2015] [Indexed: 01/06/2023]
Abstract
UNLABELLED Sarcopenia is the age-related reduction of skeletal muscle mass in older individuals. Respiratory muscle strength may be related to skeletal muscle mass and, thus, the present study attempted to estimate the risk of sarcopenia relative to decreased pulmonary function. The present findings demonstrated that low pulmonary function was associated with low muscle mass in community-dwelling older adults. INTRODUCTION Lean body mass is related to pulmonary function in patients with chronic obstructive pulmonary disease (COPD). However, the relationship between muscle mass and pulmonary function in healthy older adults has yet to be clarified. Thus, the present study investigated the association of pulmonary function with muscle mass in an older community-dwelling Korean population. METHODS This study included 463 disease-free subjects over 65 years of age who underwent anthropometric measurements, laboratory tests, spirometry, and the estimation of appendicular skeletal muscle (ASM) mass in the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES). Low muscle mass was defined as the value of ASM divided by height squared (ASM/height(2)) that was less than two standard deviations (SD) below the sex-specific mean of the young reference group. RESULTS Forced expiratory volume in 1 s (FEV1[L]) and forced vital capacity (FVC[L]) were positively correlated with ASM/height(2) in males (p < 0.001 and p = 0.001, respectively) but not in females (p = 0.360 and p = 0.779, respectively). A univariate logistic regression analysis revealed that males with low FEV1 or FVC were more likely to have low muscle mass (odds ratio [OR] = 3.11, 95% confidence interval [CI] 1.62-5.99 for FEV1; OR = 1.99, 95% CI 1.13-3.53 for FVC); similar results were found for females, but the significance was lower (OR = 11.37, 95% CI 0.97-132.91 for FEV1; OR = 7.31, 95% CI 1.25-42.74 for FVC). After adjusting for age, smoking, and moderate physical activity, a low FEV1 value was associated with low muscle mass in both males (OR = 2.90, 95% CI 1.50-5.63) and females (OR = 9.15, 95% CI 1.53-54.77). CONCLUSIONS Using nationally representative data from the 2008-2011 KNHANES, low pulmonary function was found to be associated with low muscle mass in community-dwelling older Korean adults.
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Affiliation(s)
- Y K Jeon
- Division of Endocrinology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - M J Shin
- Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - M H Kim
- Division of Pulmonology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - J H Mok
- Division of Pulmonology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - S S Kim
- Division of Endocrinology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - B H Kim
- Division of Endocrinology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - S-J Kim
- Department of Nuclear Medicine, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - Y K Kim
- Kim Yong Ki Clinic, Busan, Korea
| | - J H Chang
- Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - Y B Shin
- Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea
- Medical Research Institute, Pusan National University, Busan, Korea
| | - I J Kim
- Division of Endocrinology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.
- Medical Research Institute, Pusan National University, Busan, Korea.
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Choi YS, Kim DW, Lee SK, Chang JH, Kang SG, Kim EH, Kim SH, Rim TH, Ahn SS. The Added Prognostic Value of Preoperative Dynamic Contrast-Enhanced MRI Histogram Analysis in Patients with Glioblastoma: Analysis of Overall and Progression-Free Survival. AJNR Am J Neuroradiol 2015; 36:2235-41. [PMID: 26338911 DOI: 10.3174/ajnr.a4449] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/20/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND PURPOSE The prognostic value of dynamic contrast-enhanced MR imaging in patients with glioblastoma is controversial. We investigated the added prognostic value of dynamic contrast-enhanced MR imaging to clinical parameters and molecular biomarkers in patients with glioblastoma by using histogram analysis. MATERIALS AND METHODS This retrospective study consisted of 61 patients who underwent preoperative dynamic contrast-enhanced MR imaging for glioblastoma. The histogram parameters of dynamic contrast-enhanced MR imaging, including volume transfer constant, extravascular extracellular volume fraction, and plasma volume fraction, were calculated from entire enhancing tumors. Univariate analyses for overall survival and progression-free survival were performed with preoperative clinical and dynamic contrast-enhanced MR imaging parameters and postoperative molecular biomarkers. Multivariate Cox regression was performed to build pre- and postoperative models for overall survival and progression-free survival. The performance of models was assessed by calculating the Harrell concordance index. RESULTS In univariate analysis, patients with higher volume transfer constant and extravascular extracellular volume fraction values showed worse overall survival and progression-free survival, whereas plasma volume fraction showed no significant correlation. In multivariate analyses for overall survival, the fifth percentile value of volume transfer constant and kurtosis of extravascular extracellular volume fraction were independently prognostic in the preoperative model, and kurtosis of volume transfer constant and extravascular extracellular volume fraction were independently prognostic in the postoperative model. For progression-free survival, independent prognostic factors were minimum and fifth percentile values of volume transfer constant and kurtosis of extravascular extracellular volume fraction in the preoperative model and kurtosis of extravascular extracellular volume fraction in the postoperative model. The performance of preoperative models for progression-free survival was significantly improved when minimum or fifth percentile values of volume transfer constant and kurtosis of extravascular extracellular volume fraction were added. CONCLUSIONS Higher volume transfer constant and extravascular extracellular volume fraction values are associated with worse prognosis, and dynamic contrast-enhanced MR imaging may have added prognostic value in combination with preoperative clinical parameters, especially in predicting progression-free survival.
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Affiliation(s)
- Y S Choi
- From the Departments of Radiology and Research Institute of Radiological Science (Y.S.C., S.-K.L., S.S.A.)
| | - D W Kim
- Department of Policy Research Affairs (D.W.K.), National Health Insurance Service Ilsan Hospital, Goyang, Gyeonggi-do, Korea
| | - S-K Lee
- From the Departments of Radiology and Research Institute of Radiological Science (Y.S.C., S.-K.L., S.S.A.)
| | - J H Chang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | - S-G Kang
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | - E H Kim
- Neurosurgery (J.H.C., S.-G.K., E.H.K.)
| | | | - T H Rim
- Ophthalmology (T.H.R.), Yonsei University College of Medicine, Seoul, Korea
| | - S S Ahn
- From the Departments of Radiology and Research Institute of Radiological Science (Y.S.C., S.-K.L., S.S.A.)
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Eom KY, Chie EK, Kim K, Chang JH, Koo TR, Park JI, Park YG, Ye SJ, Ha SW. Pilot study on interfractional and intrafractional movements using surface infrared markers and EPID for patients with rectal cancer treated in the prone position. Br J Radiol 2015; 88:20150144. [PMID: 25996578 DOI: 10.1259/bjr.20150144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To evaluate interfractional and intrafractional movement of patients with rectal cancer during radiotherapy with electronic portal imaging device (EPID) and surface infrared (IR) markers. METHODS 20 patients undergoing radiotherapy for rectal cancer with body mass index ranging from 18.5 to 30 were enrolled. Patients were placed in the prone position on a couch with a leg pillow. Three IR markers were put on the surface of each patient and traced by two stereo cameras during radiotherapy on a twice-weekly basis. Interfractional isocentre movement was obtained with EPID images on a weekly basis. Movement of the IR markers was analysed in correlation with the isocentre movement obtained from the EPID images. RESULTS The maximum right-to-left (R-L) movement of the laterally located markers in the horizontal isocentre plane was correlated with isocentre translocation with statistical significance (p = 0.018 and 0.015, respectively). Movement of the surface markers was cyclical. For centrally located markers, the 95% confidence intervals for the average amplitude in the R-L, cranial-to-caudal (C-C) and anterior-to-posterior (A-P) directions were 0.86, 2.25 and 3.48 mm, respectively. In 10 patients, intrafractional movement exceeding 5 mm in at least one direction was observed. Time-dependent systematic movement of surface markers during treatment, which consisted of continuous movement towards the cranial direction and a sail back motion in the A-P direction, was also observed. CONCLUSION Intrafractional movement of surface markers has both cyclic components and time-dependent systematic components. Marker deviations exceeding 5 mm were mainly seen in the A-P direction. Pre- or post-treatment EPID images may not provide adequate information regarding intrafractional movement because of systematic movement in the A-P direction during radiotherapy. ADVANCES IN KNOWLEDGE This work uncovered a sail back motion of patients in the A-P direction during radiotherapy. Pre- or post-treatment EPID images may not provide accurate positioning of patients in the A-P direction because of this time-dependent intrafractional motion.
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Affiliation(s)
- K-Y Eom
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - E K Chie
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea.,2 Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, Republic of Korea
| | - K Kim
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - J H Chang
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - T R Koo
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - J I Park
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Y-G Park
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - S-J Ye
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea.,3 Department of Transdisciplinary Studies and Advanced Institute of Convergence Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon, Republic of Korea
| | - S W Ha
- 1 Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Republic of Korea.,2 Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, Republic of Korea
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Chang JH, Choi HG, Bae SH, Sim DH, Kim H, Chung YC. Crosstalk analysis in homogeneous multi-core two-mode fiber under bent condition. Opt Express 2015; 23:9649-9657. [PMID: 25969001 DOI: 10.1364/oe.23.009649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We analyze the inter-core crosstalk in homogeneous multi-core two-mode fibers (MC-TMFs) under bent condition by using the coupled-mode equations. In particular, we investigate the effects of the intra-core mode coupling on the inter-core crosstalk for two different types of MC-TMFs at various bending radii. The results show that the inter-core homo-mode crosstalk of LP(11) mode is dominant under the gentle fiber bending condition due to its large effective area. However, as the fiber bending becomes tight, the intra-core mode coupling is significantly enhanced and consequently makes all the inter-core crosstalk levels comparable to each other regardless of the mode. A similar tendency is observed at a reduced bending radius when the difference in the propagation constants between modes is large and core pitch is small.
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21
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Lee SH, Kim SM, Jang M, Yun BL, Kang E, Kim SW, Park SY, Ahn HS, Chang JH, Yoo Y, Song TK, Moon WK. Role of second-look ultrasound examinations for MR-detected lesions in patients with breast cancer. Ultraschall Med 2015; 36:140-148. [PMID: 25750138 DOI: 10.1055/s-0034-1399143] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE To assess the clinical value of second-look ultrasound (US) examination for the evaluation of additional enhancing lesions detected on magnetic resonance (MR) imaging. MATERIALS AND METHODS Between May 2008 and February 2011, 794 consecutive patients with histologically confirmed breast cancer underwent breast MR imaging. We included 101 patients with 132 additional enhancing breast lesions detected on MR imaging who underwent second-look US. The imaging features and lesion category according to the Breast Imaging and Reporting and Data System (BI-RADS) were assessed with MR and US imaging, respectively. RESULTS According to the BI-RADS system, 67 lesions (50.8 %) were classified as category 0, 33 lesions (25.0 %) as category 3, and 32 lesions (24.2 %) as category 4. Of the 67 indeterminate lesions on MR imaging, 34 (50.7 %) were demonstrated on second-look US. 11 of these 34 lesions showed suspicious sonographic features, including 1 lesion that showed malignancy (9.1 %, 1/11). Most of the suspicious lesions on MR imaging (26 of 32 BI-RADS category 4 lesions, 81.3 %) were demonstrated on second-look US, and 17 were malignant (65.4 %, 17/26). Of the 6 BI-RADS category 4 lesions without sonographic correlation, 1 was malignant (16.7 %, 1/6). CONCLUSION Second-look US examination was useful for evaluating MR-detected lesions in patients with breast cancer.
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MESH Headings
- Adult
- Aged
- Biopsy, Large-Core Needle
- Breast/pathology
- Breast Neoplasms/classification
- Breast Neoplasms/diagnosis
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/classification
- Carcinoma, Ductal, Breast/diagnosis
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Intraductal, Noninfiltrating/classification
- Carcinoma, Intraductal, Noninfiltrating/diagnosis
- Carcinoma, Intraductal, Noninfiltrating/pathology
- Carcinoma, Lobular/classification
- Carcinoma, Lobular/diagnosis
- Carcinoma, Lobular/pathology
- Female
- Humans
- Image Interpretation, Computer-Assisted
- Imaging, Three-Dimensional
- Magnetic Resonance Imaging
- Middle Aged
- Neoplasm Invasiveness/diagnosis
- Neoplasm Invasiveness/pathology
- Neoplasms, Multiple Primary/classification
- Neoplasms, Multiple Primary/diagnosis
- Neoplasms, Multiple Primary/pathology
- Retrospective Studies
- Sensitivity and Specificity
- Ultrasonography, Interventional
- Ultrasonography, Mammary
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Affiliation(s)
- S H Lee
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea, Republic of
| | - S M Kim
- Radiology, Seoul National University Bundang Hosipital, Seongnam, Korea, Republic of
| | - M Jang
- Radiology, Seoul National University Bundang Hosipital, Seongnam, Korea, Republic of
| | - B L Yun
- Radiology, Seoul National University Bundang Hosipital, Seongnam, Korea, Republic of
| | - E Kang
- Surgery, Seoul National University Bundang Hospital, Seongnam-si, Korea, Republic of
| | - S W Kim
- Surgery, Seoul National University Bundang Hospital, Seongnam-si, Korea, Republic of
| | - S Y Park
- Pathology, Seoul National University Bundang Hospital, Seongnam-si, Korea, Republic of
| | - H S Ahn
- Radiology, Chung-Ang University Hospital, Seoul, Korea, Republic of
| | - J H Chang
- Department of Electronic Engineering, Sogang University, Seoul, Korea, Republic of
| | - Y Yoo
- Department of Electronic Engineering, Sogang University, Seoul, Korea, Republic of
| | - T K Song
- Department of Electronic Engineering, Sogang University, Seoul, Korea, Republic of
| | - W K Moon
- Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea, Republic of
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Koo JE, Lee ST, Chang JH. UV Light and Gas Sensing Properties of Hybrid Sensor Based on Indium-Tin-Oxide Nanocrystals. J Nanosci Nanotechnol 2015; 15:669-671. [PMID: 26328423 DOI: 10.1166/jnn.2015.8358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We proposed a hybrid sensor which is able to detect both UV light and gas species. The sensor was fabricated by screen printing using indium-tin-oxide (ITO) nanocrystals. To improve the UV sensitivity, high temperature annealing (600 degrees C) under an external pressure (0.2 MPa) was applied. We could observe room temperature operation of the sensor under the simultaneous stimulation of UV light and CH4 gas. This is indicating that an improved fire warning is possible by using the proposed hybrid sensor.
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Choi HG, Chang JH, Kim H, Chung YC. Optical performance monitoring technique using software-based synchronous amplitude histograms. Opt Express 2014; 22:24024-24033. [PMID: 25321978 DOI: 10.1364/oe.22.024024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We propose and demonstrate a simple technique to monitor both the optical signal-to-noise ratio (OSNR) and chromatic dispersion (CD) by using the software-based synchronous amplitude histogram (SAH) analysis. We exploit the software-based synchronization technique to construct SAHs from the asynchronously sampled intensities of the signal. The use of SAHs facilitates the accurate extraction of the monitoring parameters at the center of the symbol. Thus, unlike in the case of using the technique based on the asynchronous amplitude histogram (AAH), this technique is not affected by the transient characteristics of the modulated signals. The performance of the proposed monitoring technique is evaluated experimentally by using 10-Gbaud quadrature phase-shift keying (QPSK) and quadrature amplitude modulation (QAM) signals over wide ranges of OSNR and CD. We also evaluate the robustness of the proposed technique to the signal's transient characteristics.
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Wang HM, Li NF, Hong J, Zhou L, Chang JH. Gender flip-flop association between genetic variations of NEDD4L and metabolic syndrome in the Kazakh general population. Genet Mol Res 2014; 13:22-31. [PMID: 24446284 DOI: 10.4238/2014.january.8.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Genetic variation is thought to contribute to etiology of metabolic syndrome (MS). Neural precursor cell expressed developmentally downregulated 4-like gene (NEDD4L) is a candidate gene for MS. This study investigated the relationship between variations of NEDD4L and MS in the Kazakh, which is an ideal population to study the genetic mechanisms of complex diseases such as MS. We screened the promoter and exons of NEDD4L in 48 Kazakh individuals with MS to identify representative variations. By genotyping the representative variations [271420T>C (rs2288774), 271454A>G (rs2288775), and 296921-296923delTTG] in the Kazakh general population, we conducted a case-control study. In female subjects, the distribution of genotypes and alleles of rs2288775 and 296921-296923delTTG differed significantly between the MS pacients and controls. In male subjects, the genotype distributions of 296921-296923delTTG were significantly different between the MS pacients and controls in the dominant model (P = 0.047). After adjustment for age, smoking, and drinking, multivariate logistic regression analysis showed that rs2288775 was significantly associated with MS [for the A/A genotype, odds ratio (OR) = 3.296, P = 0.011] in female subjects. For 296921-296923delTTG, the I/D+D/D genotype was the high-risk genotype for MS in female subjects (OR = 2.791, P = 0.035) and was a protective factor for MS in male subjects (OR = 0.580, P = 0.045). The 296921-296923delTTG variation of NEDD4L is a gender flip-flop associated with MS in Kazakh individuals. The A allele of rs2288775 may be an independent risk factor for MS in Kazakh women. The results suggest that the genetic variations of NEDD4L might be involved in the pathogenesis of MS.
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Affiliation(s)
- H M Wang
- Center of Hypertension, People's Hospital of Xinjiang Uygur Autonomous Region, Center of Diagnosis, Treatment and Research of Hypertension in Xinjiang, Urumqi, Xinjiang, China
| | - N F Li
- Center of Hypertension, People's Hospital of Xinjiang Uygur Autonomous Region, Center of Diagnosis, Treatment and Research of Hypertension in Xinjiang, Urumqi, Xinjiang, China
| | - J Hong
- Center of Hypertension, People's Hospital of Xinjiang Uygur Autonomous Region, Center of Diagnosis, Treatment and Research of Hypertension in Xinjiang, Urumqi, Xinjiang, China
| | - L Zhou
- Center of Hypertension, People's Hospital of Xinjiang Uygur Autonomous Region, Center of Diagnosis, Treatment and Research of Hypertension in Xinjiang, Urumqi, Xinjiang, China
| | - J H Chang
- Center of Hypertension, People's Hospital of Xinjiang Uygur Autonomous Region, Center of Diagnosis, Treatment and Research of Hypertension in Xinjiang, Urumqi, Xinjiang, China
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Chang JH, Choi HG, Chung YC. Achievable capacity improvement by using multi-level modulation format in trench-assisted multi-core fiber system. Opt Express 2013; 21:14262-14271. [PMID: 23787615 DOI: 10.1364/oe.21.014262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We evaluate the impacts of using multi-level modulation formats on the transmission capacity of the multi-core fiber (MCF) having trench-assisted index profile and hexagonal layout. For this evaluation, we utilize the spectral efficiency per unit area, defined as the spatial spectral efficiency (SSE). The results show that the SSE improvement achievable by using the higher-level modulation format can be reduced due to its lower tolerance to the inter-core crosstalk. We also evaluate the effects of using large effective area on the transmission capacity of the trench-assisted MCF. The results show that the use of large effective area can decrease this capacity due to the increased inter-core crosstalk and lengthened cable cutoff wavelength, although it can help increase the transmission distance. Thus, it is necessary to optimize the effective area of MCF by considering both the SSE and transmission distance. However, the results indicate that the effect of using different effective areas on the SSE-distance product is not significant, and it is not useful to increase the effective area of the trench-assisted MCF to be larger than ~110 μm(2).
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Affiliation(s)
- J H Chang
- Department of Electrical Engineering, Korea Advanced Institute of Science and Technology 335 Gwahangno, Yuseong-gu, Daejeon 305-701, South Korea
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Abstract
STUDY DESIGN Retrospective study. OBJECTIVES To identify factors associated with the development of early onset post-traumatic syringomyelia within 5 years of spinal cord injury. SETTING Department of Rehabilitation Medicine, Pusan National University School of Medicine, Korea. METHODS We retrospectively examined the records of 502 patients with traumatic cervical or thoracic spinal cord injury who underwent follow-up magnetic resonance imaging (MRI) examinations more than once a year for at least 5 years. Patients were assessed in terms of the neurological level of injury, the severity of initial spinal cord injury, the use of surgery and the extent of spinal canal involvement. The latter was evaluated by calculating the shortest antero-posterior diameter of the injured vertebral canal and the spinal reserve capacity as shown on MRI at the time of trauma onset and at the time of diagnosis of syringomyelia. RESULTS Syringomyelia developed within 5 years in 37 (7.3%) of the 502 patients. The mean age of these 37 patients was 44.6 years (range, 17-67 years) and the mean interval from spinal cord injury to onset of syringomyelia was 38.8 months (range, 2-54 months). The development of post-traumatic syringomyelia within 5 years was not significantly related to the severity or level of injury, the use of spinal surgery or the extent of spinal canal encroachment (P≥0.05 for each comparison). CONCLUSION Early onset syringomyelia occurring within 5 years after spinal cord injury was not associated with neurological injury level, severity of injury, the use of spinal surgery or canal encroachment.
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Affiliation(s)
- H-Y Ko
- Department of Rehabilitation Medicine, Pusan National University School of Medicine, Beomeo, Mulgeum, Yangsan, Korea.
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Choi HN, Kim YS, Chang JH, Jung JY, Chung WK, Park YH, Lee HH. Metastatic sarcomatoid carcinoma to liver and bone marrow in renal transplant recipient: due to exacerbation of quiescent renal cancer? A case report. Transplant Proc 2012; 44:299-302. [PMID: 22310638 DOI: 10.1016/j.transproceed.2011.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sarcomatoid carcinoma is a rare tumor with rapid growth and a poor prognosis. A 60-year-old man underwent kidney transplantation. Three months after transplantation, multiple tumors were found in the liver and bone, and the patient died several days later. Pathological examination of liver and bone marrow biopsies revealed metastatic sarcomatoid carcinoma. Pretransplantation, the patient's workup was positive only for mild thrombocytopenia and a complicated cyst with peripheral rim calcification (Bosniak IIF) in the right kidney. Retrospectively, we found the abdominal computed tomography film, which had been examined at another hospital 6 years previously. The calcified complicated cyst was a 3-cm enhancing solid mass in the right kidney, suggesting renal cell cancer. It is possible that the cancer developed from the calcified complicated cyst. In this case, immunosuppressants may have altered malignant cell proliferation, invasion, and the form of metastasis.
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Affiliation(s)
- H N Choi
- Department of Internal Medicine, Gachon University of Medicine and Science, Incheon, South Korea
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Lee HS, Chang JH, Ku SK. An immunohistochemical study of the pancreatic endocrine cells of the Korean golden frog, Rana plancyi chosenica. Eur J Histochem 2012; 56:e5. [PMID: 22472893 PMCID: PMC3352134 DOI: 10.4081/ejh.2012.e5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 12/03/2011] [Accepted: 12/07/2011] [Indexed: 11/23/2022] Open
Abstract
The regional distribution and quantitative frequency of pancreatic endocrine cells were demonstrated in the Korean golden frog (Rana plancyi chosenica Okada), which is known as a Korean endemic species, for the first time by immunohistochemical methods using specific mammalian antisera to insulin, glucagon, somatostatin and human pancreatic polypeptide (PP). In the pancreas of the Korean golden frog, all four endocrine cell types were demonstrated. Insulin- and glucagon-positive cells were located in the pancreas as single cells or islet-like clusters, respectively. Somatostatin-containing cells were also dispersed in the pancreas as single cells or clusters but in the case of clusters, they are exclusively situated in the marginal regions of insulin- or glucagon-positive cell clusters. PP-containing cells were also distributed as single cells or clusters. Clusters consisted of PP-positive cells are distributed as a core type and a marginally distributed type. Overall, there were 40.84±3.81% insulin-, 26.02±1.71% glucagon-, 7.63±2.09% somatostatin- and 25.51±3.26% PP-IR cells.
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Affiliation(s)
- H S Lee
- Department of Clinical Laboratory Science, College of Health and Therapy, Daegu Haany University, Gyeongsan, Korea
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Wang SQ, Lu F, Oh DC, Chang JH, Hanada T, Yao T. Electrochemical isothermal-capacitance-transient spectroscopy: a new depth profiling method of deep levels. Rev Sci Instrum 2011; 82:093905. [PMID: 21974598 DOI: 10.1063/1.3632118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The authors report on a new depth profiling method of deep levels, which we call electrochemical isothermal-capacitance-transient spectroscopy (EICTS). This is combined with electrochemical capacitance-voltage using the Schottky barrier of etchable electrolyte and isothermal-capacitance-transient spectroscopy using the capacitance-transient profile at a fixed temperature. We proved its validity by applying to the ZnSe:N epitaxial film of thickness of more than 1000 nm and comparing the characteristics of an obtained deep level with the results measured by conventional deep-level detection techniques. It is expected that EICTS is very effective to assess the deep levels of wide-bandgap semiconductors that suffer from various point defects and their complexes.
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Affiliation(s)
- S Q Wang
- Center for Interdisciplinary Research, Tohoku University, Aoba 6-3, Aramaki, Sendai 980-8578, Japan
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Ryu YJ, Lee JH, Chun EM, Chang JH, Shim SS. Clinical outcomes and prognostic factors in patients with tuberculous destroyed lung. Int J Tuberc Lung Dis 2011; 15:246-i. [PMID: 21219689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
OBJECTIVE To characterise the prognosis and identify factors contributing to mortality in patients with tuberculous destroyed lung (TDL). DESIGN Following a retrospective review of clinical data and radiographic findings, 169 patients with TDL were enrolled in this study. All patients were graded on a 4-point scale (field score 1-4) based on the extent of destroyed lung parenchyma on chest radiography. RESULTS The mean patient age was 64 years (range 33-90); 103 (61%) were male. The median number of hospitalisations was 1 (range 0-11) during follow-up, with a mean duration of 31 months (range 0-172). Pneumonia developed in 96 patients (57%), while 50 patients (30%) developed acute respiratory failure requiring mechanical ventilation, 37 (22%) haemoptysis, 24 (14%) spontaneous pneumothorax and 22 (13%) reactivation of tuberculosis. Overall mortality was 28% (47/169), with a median survival of 39 months (range 0-176) after diagnosis. TDL-related mortality was 19% (32/169), and a field score ≥ 3 was the only independent predictor of shorter survival based on a Cox proportional hazards model (HR 3.520, 95%CI 1.51-8.20, P = 0.004). CONCLUSION TDL has a poor prognosis, particularly in patients with more extensive lung destruction.
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Affiliation(s)
- Y J Ryu
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Ewha Medical Center and Ewha Medical Research Institute, Ewha Womans University School of Medicine, Seoul, Republic of Korea.
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Abstract
Farm tractors account for the majority of deaths and injuries among youths working on North American farms. A vehicle operator's field of vision is an important operational aspect for safe driving. However, very little is known about visual limitations of young tractor operators compared to adult operators. The main purpose of this study was to quantify limitations in fields of vision of children with different anthropometry. The study was based on assessment of 42 farm tractors in popular use in the USA. The results showed that youth operators typically had diminished fields of vision compared to the average adult operator. The degree of visual limitation is greatest for objects at close distances and when objects are straight in front of the operator/tractor. This has serious implications in terms of risks for runovers, rollovers and collisions. Study findings may help illuminate the development of policies and guidelines in tractor-related jobs for children. STATEMENT OF RELEVANCE: This study provides an ergonomic approach for evaluation of children's visual limitations in tractor operations. This approach could be used in other related cases, where children are allowed to operate vehicles.
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Affiliation(s)
- J H Chang
- Agricultural Ergonomics Research Center, Department of Biological and Agricultural Engineering, University of California, Davis, CA, USA
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32
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Chang Chien SW, Chen CY, Chang JH, Chen SH, Wang MC, Mannepalli MR. Sorption of toluene by humic acids derived from lake sediment and mountain soil at different pH. J Hazard Mater 2010; 177:1068-1076. [PMID: 20106594 DOI: 10.1016/j.jhazmat.2010.01.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 12/17/2009] [Accepted: 01/06/2010] [Indexed: 05/28/2023]
Abstract
Contamination of soil and groundwater with BTEX compounds (benzene, toluene, ethylbenzene, and xylene) depends on the sorption behavior of these compounds by soil organic matter (SOM) and humic acids (HAs). In this study sorption of toluene by HAs extracted from lake sediment and mountain soil was investigated. HA suspensions were adjusted to pH 4.00, 6.00, or 8.00 and made to the concentration of 200 mg L(-1). Each HA suspension or solution was subjected to particle size analysis using high performance particle sizer (HPPS). The particle size of HA from lake sediment was around 1000-1200 nm while that from mountain soil was 220-320 nm at suspension pH 4.00. Kinetic studies showed that sorption of toluene by the two HAs followed pseudo-first-order and mainly pseudo-zero-order kinetics. At suspension pH 4.00, the sorption of toluene by the two HAs was best described by Langmuir and Temkin adsorption isotherm models. Further, sorption of toluene by the lake sediment HA was significantly greater than that by mountain soil HA. It was thus suggested that the lake sediment HA with larger particle size may develop beneficially chemical conformation for sorption of toluene and related compounds in soil and associated environments.
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Affiliation(s)
- S W Chang Chien
- Department of Environmental Engineering and Management, Chaoyang University of Technology, Wufong Township 41349, Taichung County, Taiwan, ROC
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Kim ES, Chang JH, Choi HS, Kim J, Lee SK. Diagnostic yield of double-dose gadobutrol in the detection of brain metastasis: intraindividual comparison with double-dose gadopentetate dimeglumine. AJNR Am J Neuroradiol 2010; 31:1055-8. [PMID: 20110372 DOI: 10.3174/ajnr.a2010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Accurate assessment of the number and lesion characteristics of brain metastasis is very important in GKS. The purpose of this study was to compare the diagnostic efficacy of DD gadobutrol in the detection of brain metastases compared with a DD 0.5-mol/L gadolinium contrast, gadopentetate dimeglumine. MATERIALS AND METHODS Records of 27 patients (male to female ratio, 15:12; mean age, 57.1 years) diagnosed with brain metastasis and having undergone GKS were retrospectively analyzed. All patients underwent the first 3D-T1-GRE MR imaging with a DD of gadopentetate dimeglumine. The second MR imaging with a DD of gadobutrol was performed during GKS by using the same parameters used for the first scan. Two neuroradiologists counted the number of enhancing lesions on 2 consecutive MR imaging examinations and reached consensus. Lesion-brain CNR was measured from 45 lesions, and paired t test analysis was performed between DD gadopentetate dimeglumine and gadobutrol MR imaging. RESULTS On DD gadopentetate dimeglumine-enhanced images, a total of 130 lesions were detected visually. With DD gadobutrol, 25 additional lesions were detected on GKS MR imaging. There was no missing lesion on DD gadobutrol MR imaging. The mean lesion-brain CNR was higher on DD gadobutrol MR imaging than on DD gadopentetate dimeglumine imaging (2.17 +/- 0.19 versus 1.90 +/- 0.26; P = .00011, paired t test, 2-tailed). Only 2 cases showed lower CNR on DD gadobutrol images: 1 with hemorrhagic metastasis from renal cell carcinoma and the other with steroid treatment after the first MR imaging. CONCLUSIONS DD 1.0-mol/L gadobutrol provides higher lesion conspicuity and enhances lesion detection in brain metastasis compared with DD 0.5-mol/L gadolinium contrast agents.
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Affiliation(s)
- E S Kim
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea
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Chang JH, Gosling T, Larsen J, Powell S, Scanlon R, Chander S. Prophylactic gastrostomy tubes for patients receiving radical radiotherapy for head and neck cancers: a retrospective review. J Med Imaging Radiat Oncol 2010; 53:494-9. [PMID: 19788486 DOI: 10.1111/j.1754-9485.2009.02103.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Patients undergoing radical radiotherapy for head and neck cancers often experience significant complications. We sought to evaluate the impact of prophylactic gastrostomy tubes (PGTs) among these patients on four easily evaluable adverse outcomes, namely, absolute weight loss, percentage weight loss, admissions for nutritional reasons and treatment interruptions. A retrospective review was carried out on patients undergoing radical radiotherapy for primary head and neck cancers from September 1999 to October 2005 at the Wellington Blood and Cancer Centre (n = 71). PGTs were placed in 7 (10%) patients. Patients with PGTs were compared with the patients without PGTs (the control group) by univariate and multivariate analyses. By univariate analysis, there was no significant difference in absolute or percentage weight loss between those with PGTs and the control group. By multivariate analysis, those with PGTs lost 5.2% (P = 0.016) less weight than the control group. There were no significant differences between the two groups with regard to admissions for nutritional reasons or treatment interruptions. The use of PGTs can reduce weight loss in patients undergoing radical radiotherapy for head and neck cancers, and its use should be further evaluated in future studies.
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Affiliation(s)
- J H Chang
- Radiation Oncology Centre, Austin Health, Melbourne, Victoria, Australia
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35
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Tao CW, Taur J, Chang JH, Su SF. Adaptive fuzzy switched swing-up and sliding control for the double-pendulum-and-cart system. IEEE Trans Syst Man Cybern B Cybern 2009; 40:241-52. [PMID: 19661002 DOI: 10.1109/tsmcb.2009.2025964] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this paper, an adaptive fuzzy switched swing-up and sliding controller (AFSSSC) is proposed for the swing-up and position controls of a double-pendulum-and-cart system. The proposed AFSSSC consists of a fuzzy switching controller (FSC), an adaptive fuzzy swing-up controller (FSUC), and an adaptive hybrid fuzzy sliding controller (HFSC). To simplify the design of the adaptive HFSC, the double-pendulum-and-cart system is reformulated as a double-pendulum and a cart subsystem with matched time-varying uncertainties. In addition, an adaptive mechanism is provided to learn the parameters of the output fuzzy sets for the adaptive HFSC. The FSC is designed to smoothly switch between the adaptive FSUC and the adaptive HFSC. Moreover, the sliding mode and the stability of the fuzzy sliding control systems are guaranteed. Simulation results are included to illustrate the effectiveness of the proposed AFSSSC.
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Affiliation(s)
- Chin Wang Tao
- Department of Electrical Engineering, National I-Lan University, I-Lan 260, Taiwan
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36
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Abstract
Farm tractor work is commonly assigned to young people on North American farms, where tractors account for the majority of deaths and major portions of non-fatal trauma to working youths. However, little is known about the potential mismatch between the anthropometric and physical characteristics of children and tractor characteristics. The purpose of this study was to evaluate the ability of children of varying ages and percentiles to reach major controls on 45 tractors in common use in the US. The main study finding was that many tractor controls, especially those that are hand-operated, may not be effectively reached by the majority of youth operators aged 12 to 16 years. The study raises further serious questions about the ability of children to safely operate tractors in common use on US farms and calls for reconsideration of age guidelines for the assignment of children to tractor work on farms. This study provides novel ergonomic evidence about the ability of children to reach controls inside agricultural tractor cabins. The approach could be applied in similar situations where youths may operate other vehicles or machines. Study findings support the establishment and refinement of policies and guidelines related to youth tractor operation.
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Affiliation(s)
- F A Fathallah
- Agricultural Ergonomics Research Center, Department of Biological and Agricultural Engineering, University of California, Davis, CA, USA.
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37
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Baskerville JR, Chang JH, Viator M, Rutledge W, Miryala R, Duval KE, Nishino TK. Dose versus diagnosis: iatrogenic radiation exposure by multidetector computerised tomography in an academic emergency department with measurement of clinically actionable results and emergently treatable findings. Emerg Med J 2009; 26:15-9. [DOI: 10.1136/emj.2008.059543] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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38
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Fathallah FA, Chang JH, Berg RL, Pickett W, Marlenga B. Forces required to operate controls on farm tractors: implications for young operators. Ergonomics 2008; 51:1096-1108. [PMID: 18568967 DOI: 10.1080/00140130801961901] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Farm tractors account for the majority of fatal injuries to adolescents working in agriculture and therefore remain a leading occupational priority. The question of whether these injuries occur because adolescents are assigned tractor jobs beyond their physical capabilities has not been answered. The purpose of this study was to estimate the activation forces required to operate controls on 40 tractors in common use in the US and compare them with existing estimates of physical strength for children of varying ages and with recommended ergonomic force limits for repeatedly engaging controls. Activation forces for steering, brakes and clutch were measured on each tractor. The main study finding was that the activation forces required to operate tractors typically exceeded the physical abilities of most children aged 13 to 17 years. This raises serious questions about the ability of children to safely operate tractors in common use on US farms. This study provides an ergonomic approach for evaluating the potential mismatch between young people's strength capabilities and forces required in operating farm tractors. This approach could be used in similar situations where adolescents may operate vehicles (e.g. all-terrain vehicles), machinery or other mechanical devices requiring activation of levers and controls. Study findings potentially inform the establishment of occupational policies surrounding tractor operation by young people.
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Affiliation(s)
- F A Fathallah
- Agricultural Ergonomics Research Center, Department of Biological and Agricultural Engineering, University of California, Davis, CA, USA.
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39
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Cheng SF, Chang JH, Huang CY. Particle separation to enhance the efficiency of soil acid washing--case study on the removal of cadmium from contaminated soil in southwestern Taiwan. Environ Technol 2007; 28:1163-1171. [PMID: 17970523 DOI: 10.1080/09593332808618877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The current trend in remediating contaminated soil by acid washing is to separate the soil mass by their particles sizes prior to washing. However, there is little information about the cost-effectiveness of this practice in literature. In this research, a cadmium-contaminated agricultural field has been selected for conducting a comparative study on cadmium removal by applying the acid washing method to soil samples with and without prior particle separation. The study provides valuable information for the advancement of this method to remediate contaminated soil. The results indicate that sand particles constitute about 70% of the total soil mass but only 24% of the total cadmium. After acid washing once, less than 2% of cadmium remains; multiple washing of the sand portion is thus not cost-effective. Furthermore, after particle separation, the soil mass that needs to be washed is greatly reduced to 35%; the total cost is reduced by about one third due to the savings in the acid solution utilization and the treatment of used acid solution.
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Affiliation(s)
- S F Cheng
- Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 Gifeng E. Rd., Wufeng, Taichung County, Taiwan, ROC
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40
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Ozawa Y, Makino S, Park JY, Chang JH, Kim JH, An SH. A review of recent unexpected animal disease events in Japan and Korea and the follow-up action taken. REV SCI TECH OIE 2007; 25:125-35. [PMID: 16796042 DOI: 10.20506/rst.25.1.1649] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In Japan, the need to improve countermeasures against biological weapons was recognised after the Aum Shinrikyo cult attempted to use biological weapons in 1995. This paper describes how the two relevant ministries in Japan worked together to cope with recent disease outbreaks, including cases of classical swine fever (CSF) and avian influenza, which evidence suggests might have been the result of the deliberate misuse of unauthorised vaccines that had been illegally imported. By implementing successful control measures the two ministries were able to eradicate all the diseases within very short periods. In the past few years, the Republic of Korea has also experienced outbreaks of foot and mouth disease, highly pathogenic avian influenza, and CSF, all of which had previously been absent (or had been eradicated) in Korea. A review of the historical background, major events of the outbreaks and the control measures which were implemented are presented here.
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Affiliation(s)
- Y Ozawa
- OIE, 2-30-3 Utsukushigaoka, Aoba-ku, Yokohama 225-0002, Japan
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41
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Jung MN, Ha SY, Kim HS, Ko HJ, Ko H, Lee WH, Oh DC, Murakami Y, Yao T, Chang JH. The shape control of ZnO based nanostructures. J Nanosci Nanotechnol 2006; 6:3628-32. [PMID: 17252825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Tetrapod-shape ZnO nanostructures are formed on Si substrates by vapor phase transportation method. The effects of two important growth parameters, growth temperature and VI/II ratio, are investigated. The growth temperature is varied in the range from 600 degrees C to 900 degrees C to control the vapor pressure of group II-element and the formation process of nanostructures. VI/II ratio was changed by adjusting the flux of carrier gas which affects indirectly the supplying rate of group VI-element. From the scanning electron microscopy (SEM), systematic variation of shape including cluster, rod, wire and tetrapod was observed. ZnO tetrapods, formed at 800 degrees C under the carrier gas flux of 0.5 cc/mm2 min, show considerably uniform shape with 100 nm thick and 1-1.5 microm long legs. Also stoichiometric composition (O/Zn - 1) was observed without any second phase structures. While, the decrease of growth temperature and the increase of carrier gas flux, results in the irregular shaped nanostructures with non-stoichiometric composition. The excellent luminescence properties, strong excitonic UV emission at 3.25 eV without deep level emission, indicate that the high crystalline quality tetrapod structures can be formed at the optimized growth conditions.
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Affiliation(s)
- M N Jung
- Major of Semiconductor Physics, KMU, Pusan, Korea
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42
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Ha SY, Jung MN, Park SH, Ko HJ, Ko H, Oh DC, Yao T, Chang JH. Growth of well-aligned ZnO nanorods using auge catalyst by vapor phase transportation. J Nanosci Nanotechnol 2006; 6:3624-7. [PMID: 17252824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Well-aligned ZnO nanorods have been achieved using new alloy (AuGe) catalyst. Zn powder was used as a source material and it was transported in a horizontal tube furnace onto an AuGe deposited Si substrates. The structural and optical properties of ZnO nanorods were characterized by scanning electron microscopy, high resolution X-ray diffraction, and photoluminescence. ZnO nanorods grown at 650 degrees C on 53 nm thick AuGe layer show uniform shape with the length of 8 +/- 0.5 microm and the diameter of 150 +/- 5 nm. Also, the tilting angle of ZnO nanorods (+/- 5.5 degrees) is confirmed by HRXRD. High structural quality of the nanorods is conformed by the photoluminescence measurement. All samples show strong UV emission without considerable deep level emission. However, weak deep level emission appears at high (700 degrees C) temperature due to the increase of oxygen desertion.
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Affiliation(s)
- S Y Ha
- Major of Semiconductor Physics, Korea Maritime University, Pusan, Korea
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43
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Chang JH, McCluskey PJ, Grigg JR. Recurrent hypopyon in chronic anterior uveitis of pauciarticular juvenile idiopathic arthritis. Br J Ophthalmol 2006; 90:1327-8. [PMID: 16980650 PMCID: PMC1857443 DOI: 10.1136/bjo.2006.096313] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Microbial agents have an important role in the pathogenesis of various inflammatory eye diseases, such as uveitis and keratitis. Microbial infections of the eye such as microbial keratitis, ocular onchocerciasis, bacterial endophthalmitis, viral retinitis, and other infectious uveitis are unfortunately common. In addition, microbial agents have been implicated in the pathogenesis of "non-infectious" immune mediated diseases such as HLA-B27 associated acute anterior uveitis. Toll-like receptors (TLR) are a family of pattern recognition receptors that initiates rapid host innate immune response to microbial components known as pathogen associated molecular patterns, which are unique to a given class of microbes, such as lipopolysaccharide of Gram negative bacteria. Recent in vitro and in vivo studies have demonstrated the expression and function of TLRs in the eye, with significant implications for better understanding of ocular immunity and the pathogenesis of inflammatory eye diseases affecting the cornea, uvea, and retina.
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Affiliation(s)
- J H Chang
- School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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45
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Hwang SL, Chang JH, Cheng CY, Howng SL, Sy WD, Lieu AS, Lin CL, Lee KS, Hong YR. The expression of rac1 pseudogene in human tissues and in human brain tumors. Eur Surg Res 2005; 37:100-4. [PMID: 15905615 DOI: 10.1159/000084540] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Accepted: 10/12/2004] [Indexed: 01/20/2023]
Abstract
BACKGROUND Recent studies have demonstrated that Rac is a regulator of cell morphology and growth. Rac1 gene appears to have involvement in tumorigenesis and metastatic potential. In our previous study of rac1 gene in 45 human brain tumors, rac1 pseudogene was found. The rac1 pseudogene is an intronless pseudogene and has a similarity of 86% with rac1 nucleotide sequence. The rac1 pseudogene contains 579 nucleotides and only 46 amino acids can be translated. Little is known about the expression of rac1 pseudogene in human tissues or tumors. MATERIALS AND METHODS The expression of rac1 gene and rac1 pseudogene in different human tissues and brain tumors was investigated by the use of reverse transcriptase-polymerase chain reaction and Northern blotting. RESULTS The rac1 gene is apparently expressed in these 8 human tissues. The rac1 pseudogene is also apparently expressed in human tissues except for brain tissue. The overexpression of rac1 gene in brain tumors was 8% (2/25) and the overexpression of rac1 pseudogene was 76.9% (20/26). Only two astrocytomas had overexpression of rac1 gene, compared with normal brain tissues. The overexpression of rac1 pseudogene was 6 of 9 in meningiomas, 7 of 9 in astrocytomas, and 7 of 8 in pituitary adenomas. CONCLUSIONS High frequency of overexpression of rac1 pseudogene was detected in the human brain tumors when compared with that expressed in the normal brain tissues. Our study suggested that the rac1 pseudogene may play an important role of the tumorigenesis of brain.
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Affiliation(s)
- S L Hwang
- Division of Neurosurgery, Kaohsiung Medical University, Kaohsiung, Taiwan
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46
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Affiliation(s)
- K Oh
- Department of Neurology, Korea University School of Medicine, Seoul, Korea
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47
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Brown MF, Avery M, Brissette WH, Chang JH, Colizza K, Conklyn M, DiRico AP, Gladue RP, Kath JC, Krueger SS, Lira PD, Lillie BM, Lundquist GD, Mairs EN, McElroy EB, McGlynn MA, Paradis TJ, Poss CS, Rossulek MI, Shepard RM, Sims J, Strelevitz TJ, Truesdell S, Tylaska LA, Yoon K, Zheng D. Novel CCR1 antagonists with improved metabolic stability. Bioorg Med Chem Lett 2004; 14:2175-9. [PMID: 15081003 DOI: 10.1016/j.bmcl.2004.02.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Revised: 02/04/2004] [Accepted: 02/05/2004] [Indexed: 11/23/2022]
Abstract
The synthesis, biological activity, and pharmacokinetic profile of novel CCR1 antagonists are described.
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Affiliation(s)
- Matthew F Brown
- Pfizer Global Research and Development, Eastern Point Road, Groton, CT 06340, USA.
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48
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Roh JY, Li MS, Chang JH, Choi JY, Shim HJ, Shin SC, Boo KS, Je YH. Expression and characterization of a recombinant Cry1Ac crystal protein with enhanced green fluorescent protein in acrystalliferous Bacillus thuringiensis. Lett Appl Microbiol 2004; 38:393-9. [PMID: 15059210 DOI: 10.1111/j.1472-765x.2004.01505.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To investigate fusion expression between Bacillus thuringiensis crystal protein and a foreign protein, the expression of a fusion protein comprised of Cry1Ac, and enhanced green fluorescent protein (EGFP) in B. thuringiensis Cry(-)B strain was examined. METHODS AND RESULTS The N-terminal fusion expression of EGFP in Cry1Ac was attempted under the control of the native cry1Ac promoter. The EGFP gene was cloned into pProMu and named pProMu-EGFP. The transformant, ProMu-EGFP/CB produced parasporal inclusions that were of bipyramidal-shaped crystals in size ranging from 200 to 300 nm. The fusion protein was approximately 150 kDa and identified by the immunoblot analysis using a Cry1Ac antibody and also a GFP antibody. The LC(50) of the ProMu-EGFP/CB was twofold higher when compared with that by the ProAc/CB. However, the crystal protein produced by the ProMu-EGFP/CB was effective on Plutella xylostella larvae. CONCLUSIONS The ProMu-EGFP/CB produced bipyramidal shaped and insecticidal crystals comprising fusion proteins. SIGNIFICANCE AND IMPACT OF THE STUDY Through the N-terminal fusion expression of EGFP and Cry1Ac, expression and crystallization between the B. thuringiensis crystal protein and a foreign protein were validated.
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Affiliation(s)
- J Y Roh
- School of Agricultural Biotechnology, Seoul National University, Seoul, Korea
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Abstract
We report an example of subarachnoid neurocysticercosis located in the left cerebellopontine cistern of a 60 year-old man. The negative results of the serum and cerebrospinal fluid tests for parasites and the unusual MRI findings, such as the uncommon shape, location and extension pattern, made differential diagnosis difficult. Neurocysticercosis was confirmed by surgical and histopathological findings. The clinical and radiographic features of neurocysticercosis are highly variable. In an endemic area, neurocysticercosis should be considered in the differential diagnosis.
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Affiliation(s)
- J H Chang
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea
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Chang JH, Lee KC, Choi HJ, Yoon JH, Choi MC. Radiographic contrast study of the upper gastrointestinal tract of eight dogs using carboxymethylcellulose mixed with a low concentration of barium sulphate. Vet Rec 2004; 154:201-4. [PMID: 15002400 DOI: 10.1136/vr.154.7.201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
To evaluate the efficacy of a mixture of barium and carboxymethylcellulose (CMC) suspension in upper gastrointestinal contrast studies, and to determine its optimal concentration and method for use, eight healthy beagle dogs underwent conventional upper gastrointestinal contrast imaging and a modified procedure using a mixture of barium sulphate and CMC. Four different procedures were carried out on the dogs at weekly intervals. In the first, the dogs were administered 10 ml/kg of 60 per cent barium suspension for conventional study of the upper gastrointestinal tract. The second, third and fourth procedures involved modified methods in which the dogs were given 10 ml/kg of a mixture of 25 per cent barium and 0.5 per cent CMC prepared to a low, moderate or high viscosity, respectively. All four procedures were evaluated by four criteria: the quality of the images obtained, the translucency and distensibility of the bowel, and the transit time. The method of imaging which used a moderately viscious CMC formulation provided excellent image quality, high translucency, a rapid transit time and suitable bowel distension to enable more precise diagnosis of disorders of the gastrointestinal tract.
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Affiliation(s)
- J H Chang
- Department of Veterinary Radiology, Veterinary Medical Teaching Hospital, Seoul National University, Seoul 151-742, Republic of Korea
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