Transmission Line Modeling and Algorithm Analysis Considering Parameter Asymmetry and Transient High-frequency Components

Mo Shixun,Lv Zhipeng,Han Kunlun,Yuan Rongji,Yang Hao,Jiang Kunping,Liang Zhenshen 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.2

When the power system is disturbed or the operation mode is changed, the electromagnetic transient process will occur, which will lead to the high frequency transient component and aff ect the protection and control of the power system. Therefore, attention should be paid to the analysis of high-frequency transient components when modeling and analyzing the system model. In view of the fact that the symmetrical-component theory is not suitable for asymmetric transmission lines and the phasor method is not suitable for transient analysis and calculation, this paper uses the phase coordinate approach and Laplace transform to derive the node voltage equation of three-phase π type transmission lines in frequency domain, which can be used to calculate the transient response of transmission lines caused by the change of operation mode or disturbance. And vectorized NILT is used to calculate the time domain solution, which greatly improves the calculation speed. The calculated results are basically consistent with those of ATP-EMTP, and can fully refl ect the transient characteristics. This method lays a foundation for analyzing the infl uence of high frequency transient components on power system and fault analysis considering transient process.

Expression and Clinical Significance of MicroRNA-376a in Colorectal Cancer

Mo, Zhan-Hao,Wu, Xiao-Dong,Li, Shuo,Fei, Bing-Yuan,Zhang, Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

The incidence of colorectal cancer (CRC) is increasing in many Asian countries and microRNAs have already been proven to be associated with tumorigenesis. Currently, microRNA-376a (miR-376a) expression and association with clinical factors in CRC remains unclear. In this study, real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was carried out on 53 matched pairs of CRC and adjacent normal mucosa to investigate the expression levels of miR-376a. According to the high or low expression of miR-376a, patients were divided into two groups. The relationship between miR-376a expression and clinicopathological factors of 53 patients was evaluated. Survival analysis of 53 CRC patients was performed with clinical follow-up information and survival curves were assessed by the Kaplan-Meier method. Immunohistochemistry (IHC) staining was performed on sections of paraffin-embedded tissue to investigate the vascular endothelial growth factor (VEGF) expression. MiR-376a showed low expression in cancer tissues compared to the adjacent normal tissues and altered high miR-376a expression tended to be positively correlated with advanced lymph node metastasis and shorter patient survival. VEGF IHC positivity was significantly more common in patients with high expression levels of miR-376a.Those results demonstrated that miR-376a may be a meaningful prognostic biomarker and potential therapeutic target in colorectal cancer.

Prognostic Value of Serum Epstein–Barr Virus Antibodies and Their Correlation with TNM Classification in Patients with Locoregionally Advanced Nasopharyngeal Carcinoma

Wan-Ru Zhang,Yu-Yun Du,Chun-Yan Guo,Han-Xing Zhou,Jie-Yi Lin,Xiao-Han Meng,Hao-Yuan Mo,Dong-Hua Luo 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose This study assessed the correlation between Epstein-Barr virus (EBV) biomarkers and the eighth American Joint Committee on Cancer staging system and the prognostic values of IgG antibodies against replication and transcription activator (Rta-IgG), IgA antibodies against Epstein-Barr nuclear antigen 1, and BamH1 Z transactivator (Zta-IgA) in locoregionally advanced nasopharyngeal carcinoma (NPC) patients. Materials and Methods Serum EBV antibody levels were measured by enzyme-linked immunosorbent assay in 435 newly diagnosed stage III-IVA NPC patients administered intensity-modulated radiation therapy±chemotherapy. The primary endpoint was progression-free survival (PFS). Results Rta-IgG and Zta-IgA levels were positively correlated with the N category and clinical stage. Patients with high Rta-IgG levels (> 29.07 U/mL) showed a significantly inferior prognosis as indicated by PFS (77% vs. 89.8%, p=0.004), distant metastasis–free survival (DMFS) (88.3% vs. 95.8%, p=0.021), and local recurrence-free survival (LRFS) (91.2% vs. 98.3%, p=0.009). High Rta-IgG levels were also significantly associated with inferior PFS and LRFS in multivariable analyses. In the low-level EBV DNA group (≤ 1,500 copies/mL), patients with high Rta-IgG levels had significantly inferior PFS and DMFS (both p < 0.05). However, in the high-level EBV DNA group, Rta-IgG levels were not significantly associated with PFS, DMFS, and LRFS. In the advanced T category (T3-4) subgroup, high Rta-IgG levels were also significantly associated with inferior PFS, DMFS, and LRFS (both p < 0.05). Conclusion Rta-IgG and Zta-IgA levels were strongly correlated with the TNM classification. Rta-IgG level was a negative prognostic factor in locoregionally advanced NPC patients, especially those with advanced T category or low EBV DNA level.

Complement Receptor 1 Expression in Peripheral Blood Mononuclear Cells and the Association with Clinicopathological Features And Prognosis of Nasopharyngeal Carcinoma

He, Jian-Rong,Xi, Jing,Ren, Ze-Fang,Qin, Han,Zhang, Ying,Zeng, Yi-Xin,Mo, Hao-Yuan,Jia, Wei-Hua Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Purpose: Complement receptor 1 (CR1) is induced by Epstein-Barr virus (EBV) and may be a potential biomarker of nasopharyngeal carcinoma (NPC). We conducted the present study to evaluate the association of CR1 expression with clinicopathological features and prognosis of NPC. Methods: We enrolled 145 NPC patients and 110 controls. Expression levels of CR1 in peripheral blood mononuclear cells (PBMCs) were detected using quantitative real-time PCR and associations with clinicopathological features and prognosis were examined. Results: CR1 levels in the NPC group [3.54 (3.34, 3.79)] were slightly higher than those in the controls [3.33 (3.20, 3.47)] (P<0.001). Increased CR1 expression was associated with histology classification (type III vs. type II, P=0.002), advanced clinical stage (P=0.003), high T stage (P=0.017), and poor overall survival (HR, 4.89; 95% CI, 1.23-19.42; P=0.024). However, there were no statistically significant differences in CR1 expression among N or M stages. Conclusion: These findings indicate that CR1 expression in PBMCs may be a new biomarker for prognosis of NPC and a potential therapeutic target.

The Prognostic Value of Treatment-Related Lymphopenia in Nasopharyngeal Carcinoma Patients

Li-Ting Liu,Qiu-Yan Chen,Lin-Quan Tang,Shan-Shan Guo,Ling Guo,Hao-Yuan Mo,Ming-Yuan Chen,Chong Zhao,Xiang Guo,Chao-Nan Qian,Mu-Sheng Zeng,Jin-Xin Bei,Jing Tan,Shuai Chen,Ming-Huang Hong,Jian-Yong Shao 대한암학회 2018 Cancer Research and Treatment Vol.50 No.1

Purpose This study was conducted to evaluate the prognostic value of treatment-related lymphopenia in patients with nasopharyngeal carcinoma (NPC). Materials and Methods A total of 413 consecutive stage II-IVb NPC patients treated with concurrent chemoradiotherapy (CCRT) were enrolled. The overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. Results A minimum (mini)–absolute lymphocyte counts (ALC) of < 390 cells/μL or ALC after 3 months of CCRT (post3m-ALC) < 705 cells/μL was significantly associated with worse outcome than mini-ALC ! 390 cells/μL (OS, p=0.002; PFS, p=0.005; DMFS, p=0.004) or post3m-ALC ! 705 cells/μL (OS, p < 0.001; PFS, p < 0.001; DMFS, p=0.001). Patients with lymphopenia (mini-ALC < 390 cells/μL and post3m-ALC < 705 cells/μL) had a worse prognosis than those without lymphopenia (mini-ALC ! 390 cells/μL and post3m-ALC ! 705 cells/μL) (OS, p < 0.001; PFS, p < 0.001; DMFS, p < 0.001). Multivariate analysis revealed that post3m-ALC was an independent prognostic factor for OS (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.12 to 2.78; p=0.015), PFS (HR, 1.86; 95% CI, 1.23 to 2.82; p=0.003), and DMFS (HR, 1.87; 95% CI, 1.13 to 3.08; p=0.014). Multivariate analysis also revealed that patients with lymphopenia had a high risk of death (HR, 3.79; 95% CI, 1.75 to 8.19; p=0.001), disease progression (HR, 2.93; 95% CI, 1.59 to 5.41; p=0.001), and distant metastasis (HR, 3.89; 95% CI, 1.67 to 9.10; p=0.002). Multivariate analysis performed with time dependent Cox regression demonstrated ALC was an independent prognostic factor for OS (HR, 0.995; 95% CI, 0.991 to 0.999; p=0.025) and PFS (HR, 0.993; 95% CI, 0.988 to 0.998; p=0.006). Conclusion Treatment-related lymphopenia was a poor prognostic factor in NPC patients.

Pretreatment Serum Amyloid A and C-reactive Protein Comparing with Epstein-Barr Virus DNA as Prognostic Indicators in Patients with Nasopharyngeal Carcinoma: A Prospective Study

Qiu-Yan Chen,Qing-Nan Tang,Lin-Quan Tang,Wen-Hui Chen,Shan-Shan Guo,Li-Ting Liu,Chao-Feng Li,Yang Li,Yu-Jing Liang,Xue-Song Sun,Ling Guo,Hao-Yuan Mo,Rui Sun,Dong-Hua Luo,Yu-Ying Fan,Yan He,Ming-Yuan C 대한암학회 2018 Cancer Research and Treatment Vol.50 No.3

Purpose The measuring Epstein-Barr virus (EBV) DNA is an important predictor of nasopharyngeal carcinoma (NPC). This study evaluated the predictive value of pretreatment serum amyloid A (SAA) and C-reactive protein (CRP) comparing with EBV DNA in patients with NPC. Materials and Methods In an observational study of 419 non-metastatic NPC patients, we prospectively evaluated the prognostic effects of pretreatment SAA, CRP, and EBV DNA on survival. The primary endpoint was progress-free survival (PFS). Results The median level of SAA and CRP was 4.28 mg/L and 1.88 mg/L, respectively. For the high- SAA group (> 4.28 mg/L) versus the low-SAA ( 4.28 mg/L) group and the high-CRP group (> 1.88 mg/L) versus the low-CRP ( 1.88 mg/L) group, the 5-year PFS was 64.5% versus 73.1% (p=0.013) and 65.2% versus 73.3% (p=0.064), respectively. EBV DNA detection showed a superior predictive result, the 5-year PFS in the EBV DNA  1,500 copies/mL group was obviously different than the EBV DNA < 1,500 copies/mL group (62.2% versus 77.8%, p < 0.001). Multifactorial Cox regression analysis confirmed that in the PFS, the independent prognostic factors were including EBV DNA (hazard ratio [HR], 1.788; p=0.009), tumour stage (HR, 1.903; p=0.021), and node stage (HR, 1.498; p=0.049), but the SAA and CRP were not included in the independent prognostic factors. Conclusion The results of SAA and CRP had a certain relationship with the prognosis of NPC, and the prognosis of patients with high level of SAA and CRP were poor. However, the predictive ability of SAA and CRP was lower than that of EBV DNA.

The Characteristics and Survival Outcomes in Patients Aged 70 Years and Older with Nasopharyngeal Carcinoma in the Intensity-Modulated Radiotherapy Era

Ya-Nan Jin,Wang-Jian Zhang,Xiu-Yu Cai,Mei-Su Li,Wayne R. Lawrence,Si-Yang Wang,Dong-Mei Mai,Yu-Yun Du,Dong-Hua Luo,Hao-Yuan Mo 대한암학회 2019 Cancer Research and Treatment Vol.51 No.1

Purpose We aim to examine nasopharyngeal carcinoma (NPC) characteristics and survival outcomes in patients aged 70 years and older in the intensity-modulated radiotherapy (IMRT) era. Materials and Methods From 2006 to 2013, 126 non-metastatic NPC patients aged  70 years who were treated with IMRT +/ chemotherapy were included. Adult Comorbidity Evaluation 27 (ACE-27) was used to measure patient comorbidities. The overall survival (OS) and cancer-specific survival (CSS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. The Cox proportional hazards model was used to carry out multivariate analyses. Results For the entire group, only two patients (1.6%) presented stage I disease, and up to 84.1% patients had stage III-IVB disease. All patients had a comorbidity score of 0 in 24 (19.0%), 1 in 45 (35.7%), 2 in 42 (33.3%), and 3 in 15 (11.9%) patients. The main acute grade during radiotherapy was 3-4 adverse events consisting of mucositis (25.4%), bone marrow suppression (16.7%), and dermatitis (8.7%). After treatment, four patients (3.2%) developed temporal lobe injury. Five-year CSS and OS rates were 67.3% (95% confidence interval [CI], 58.6% to 77.4%) and 54.0% (95% CI, 45.6% to 63.9%), respectively. Five-year OS was significantly higher for ACE-27 score 0-1 than ACE-27 score 2-3 (72.9% and 39.9%, respectively; p < 0.001). Multivariate analyses showed ACE-27 score 0-1 was significantly associated with superior OS (hazard ratio [HR], 3.02; 95% CI, 1.64 to 5.55; p < 0.001). In addition, the rate of OS was higher for stage I-III than that of stage IV, with borderline significance (HR, 1.67; 95% CI, 0.99 to 2.82; p=0.053). But no significant advantage was observed in OS when chemotherapy was used (p > 0.05). Conclusion Our findings suggest IMRT +/– chemotherapy has a manageable toxicity and provides an acceptable survival in patients aged  70 years with NPC. ACE-27 score was significantly associated with survival outcomes in this group population.

Combination of Tumor Volume and Epstein-Barr Virus DNA Improved Prognostic Stratification of Stage II Nasopharyngeal Carcinoma in the Intensity Modulated Radiotherapy Era: A Large-Scale Cohort Study

Qiu-Yan Chen,Shao-Yan Guo,Lin-Quan Tang,Tong-Yu Lu,Bo-Lin Chen,Qi-Yu Zhong,Meng-Sha Zou,Qing-Nan Tang,Wen-Hui Chen,Shan-Shan Guo,Li-Ting Liu,Yang Li,Ling Guo,Hao-Yuan Mo,Rui Sun,Dong-Hua Luo,Chong Zha 대한암학회 2018 Cancer Research and Treatment Vol.50 No.3

Purpose Little is known about combination of the circulating Epstein-Barr viral (EBV) DNA and tumor volume in prognosis of stage II nasopharyngeal carcinoma (NPC) patients in the intensity modulated radiotherapy (IMRT) era. We conducted this cohort study to evaluate the prognostic values of combining these two factors. Materials and Methods By Kaplan-Meier, we compare the differences of survival curves between 385 patients with different EBV DNA or tumor volume levels, or with the combination of two biomarkers mentioned above. Results Gross tumor volume of cervical lymph nodes (GTVnd, p < 0.001) and total tumor volume (GTVtotal, p < 0.001) were both closely related to pretreatment EBV DNA, while gross tumor volume of nasopharynx (GTVnx, p=0.047) was weakly related to EBV DNA. EBV DNA was significantly correlated with progress-free survival (PFS, p=0.005), locoregional-free survival (LRFS, p=0.039), and distant metastasis-free survival (DMFS, p=0.017), while GTVtotal, regardless of GTVnx and GTVnd, had a significant correlation with PFS and LRFS. The p-values of GTVtotal for PFS and LRFS were 0.008 and 0.001, respectively. According to GTVtotal and pretreatment EBV DNA level, patients were divided into a low-risk group (EBV DNA 0 copy/mL, GTVtotal < 30 cm3; EBV DNA 0 copy/mL, GTVtotal  30 cm3; or EBV DNA > 0 copy/mL, GTVtotal < 30 cm3) and a high-risk group (EBV DNA > 0 copy/mL, GTVtotal  30 cm3). When patients in the low-risk group were compared with those in the high-risk group, 3-year PFS (p=0.003), LRFS (p=0.010), and DMFS (p=0.031) rates were statistically significant. Conclusion Pretreatment plasma EBV DNA and tumor volume were both closely correlated with prognosis of stage II NPC patients in the IMRT era. Combination of EBV DNA and tumor volume can refine prognosis and indicate for clinical therapy.