Clinical Application of Dose Reconstruction Based on Full-Scope Monte Carlo Calculations: Composite Dose Reconstruction on a Deformed Phantom

Inhwan Yeo,Qianyi Xu,Yan Chen,Jae Won Jung,Jong Oh Kim 한국의학물리학회 2014 의학물리 Vol.25 No.3

The purpose of this study was to develop a system of clinical application of reconstructed dose that includesdose reconstruction, reconstructed dose registration between fractions of treatment, and dose-volume-histogramgeneration and to demonstrate the system on a deformable prostate phantom. To achieve this purpose, adeformable prostate phantom was embedded into a 20 cm-deep and 40 cm-wide water phantom. The phantomwas CT scanned and the anatomical models of prostate, seminal vesicles, and rectum were contoured. Acoplanar 4-field intensity modulated radiation therapy (IMRT) plan was used for this study. Organ deformationwas simulated by inserting a “transrectal” balloon containing 20 ml of water. A new CT scan was obtained andthe deformed structures were contoured. Dose responses in phantoms and electronic portal imaging device(EPID) were calculated by using the XVMC Monte Carlo code. The IMRT plan was delivered to the two phantomsand integrated EPID images were respectively acquired. Dose reconstruction was performed on these imagesusing the calculated responses. The deformed phantom was registered to the original phantom using an in-housedeveloped software based on the Demons algorithm. The transfer matrix for each voxel was obtained and usedto correlate the two sets of the reconstructed dose to generate a cumulative reconstructed dose on the originalphantom. Forwardly calculated planning dose in the original phantom was compared to the cumulativereconstructed dose from EPID in the original phantom. The prescribed 200 cGy isodose lines showed littledifference with respect to the “prostate” and “seminal vesicles”, but appreciable difference (3%) was observedat the dose level greater than 210 cGy. In the rectum, the reconstructed dose showed lower volume coverageby a few percent than the plan dose in the dose range of 150 to 200 cGy. Through this study, the system ofclinical application of reconstructed dose was successfully developed and demonstrated. The organ deformationsimulated in this study resulted in small but observable dose changes in the target and critical structure.

CNN-based damage identification method of tied-arch bridge using spatial-spectral information

Yuanfeng Duan,Qianyi Chen,Hongmei Zhang,Chung Bang Yun,Sikai Wu,Qi Zhu 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.5

In the structural health monitoring field, damage detection has been commonly carried out based on the structural model and the engineering features related to the model. However, the extracted features are often subjected to various errors, which makes the pattern recognition for damage detection still challenging. In this study, an automated damage identification method is presented for hanger cables in a tied-arch bridge using a convolutional neural network (CNN). Raw measurement data for Fourier amplitude spectra (FAS) of acceleration responses are used without a complex data pre-processing for modal identification. A CNN is a kind of deep neural network that typically consists of convolution, pooling, and fully-connected layers. A numerical simulation study was performed for multiple damage detection in the hangers using ambient wind vibration data on the bridge deck. The results show that the current CNN using FAS data performs better under various damage states than the CNN using time-history data and the traditional neural network using FAS. Robustness of the present CNN has been proven under various observational noise levels and wind speeds.

Ferulic acid protects cardiomyocytes from TNF-a/cycloheximide-induced apoptosis by regulating autophagy

Chunxiao Li,Lu Chen,Min Song,Zhirui Fang,Lusha Zhang,Joel Wake Coffie,Liyuan Zhang,Lulu Ma,Qianyi Wang,Wenjie Yang,Leyu Fang,Shaoxia Wang,Xiumei Gao,Hong Wang 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.8

Acute myocardial infarction (AMI) resultsin irreversible cardiac cell damage or death because ofdecreased blood fl ow to the heart. Apoptosis plays an importantrole in the process of tissue damage after myocardialinfarction (MI), which has pathological and therapeuticimplications. Ferulic acid (FA) is a phenolic acid endowedwith strong antioxidative and cytoprotective activities. Thepresent study aimed to investigate whether FA protectscardiomyocytes from apoptosis by regulating autophagy,which is a cellular self-digestion process, and one of thefi rst lines of defense against oxidative stress. Apoptosis wasinduced by TNF-α (10 ng/mL) and cycloheximide (CHX,5 μg/mL) in rat H9c2 cardiomyocytes. FA-inhibited TNF-α/CHX-induced apoptosis was determined by the quantifi cationof TUNEL-positive cells, and the eff ect was associatedwith decreased ROS production and inhibited caspase3activation. FA treatment enhanced autophagy and increasedautophagy-associated protein expression, leading to an inhibitionof mTOR signaling. When co-treated with 3-methyladenine(3-MA), an autophagy inhibitor, the anti-apoptoticeff ect of FA was attenuated. In an in vivo mouse MI model,FA treatment decreased the apoptotic cell number, reducedinfarct size, and improved cardiac performance, as determinedby histological and echocardiographic assessments. Taken collectively, these results suggest that FA could protectcardiomyocytes from apoptosis by enhancing autophagy.

Clinical Application of Dose Reconstruction Based on Full-Scope Monte Carlo Calculations: Composite Dose Reconstruction on a Deformed Phantom

Yeo, Inhwan,Xu, Qianyi,Chen, Yan,Jung, Jae Won,Kim, Jong Oh Korean Society of Medical Physics 2014 의학물리 Vol.25 No.3

본 연구의 목적은 흡수선량 재구성, 방사선 치료간의 재구성된 선량의 등록, 선량-체적 히스토그램의 생산등을 수행하는 선량 재구성의 임상적 응용시스템을 만들고 그것을 변형된 전립선 팬텀에 적용하는 것이다. 이를 위해 변형가능한 전립선 팬텀을 20 cm 깊이와 40 cm너비의 물팬텀에 집에 넣었다. 이것의 영상을 얻고, 전립선, 정낭 및 항문의 윤곽을 그렸다. 동일 평면에서 네개의 조사문을 이용하여 세기 변조계획을 세웠다.항문에 20 ml의 물풍선을 삽입하여 장기를 변형시켰다. 영상을 다시 획득하여 위 장기의 윤곽을 그렸다. XVMC몬테칼로 코드를 사용하여 두 팬텀및 EPID내에서 선량반응 인자를 계산하였다. 세기변조계획에서 얻어진 방사선을 두팬텀에 조사하여 EPID에서 적분형 영상을 얻었다. Demons 방법을 사용하여 변형된 팬텀을 변형전 팬텀에 등록시켰다. 이를 통해 단위체적별 위치변이 정보를 얻었고 이를 이용해 두 팬텀의 재 구성된 선량을 합하여 변형전 팬텀에 생산해 냈다. 순방향으로 계산된 치료계획 선량을 합산된 재구성된 선량과 비교하였다. 200 cGy에서 전립선과 정낭이 받든 체적은 차이를 거의 보이지 않았으나, 210 cGy 이상에서는 3%가량 차이를 보였다. 항문에서는 150-200 cGy영역에서 재구성된 선량에 의하여 받은 체적은 치료 계획과 비교하여 3% 이상 적었다. 본 연구를 통하여 선량 재구성의 임상적 응용시스템이 성공적으로 만들어 졌다. 변형된 전립선 팬텀에 적용되어 작지 않은 선량의 차이를 목표장기와 보호 장기에 보였다. The purpose of this study was to develop a system of clinical application of reconstructed dose that includes dose reconstruction, reconstructed dose registration between fractions of treatment, and dose-volume-histogram generation and to demonstrate the system on a deformable prostate phantom. To achieve this purpose, a deformable prostate phantom was embedded into a 20 cm-deep and 40 cm-wide water phantom. The phantom was CT scanned and the anatomical models of prostate, seminal vesicles, and rectum were contoured. A coplanar 4-field intensity modulated radiation therapy (IMRT) plan was used for this study. Organ deformation was simulated by inserting a "transrectal" balloon containing 20 ml of water. A new CT scan was obtained and the deformed structures were contoured. Dose responses in phantoms and electronic portal imaging device (EPID) were calculated by using the XVMC Monte Carlo code. The IMRT plan was delivered to the two phantoms and integrated EPID images were respectively acquired. Dose reconstruction was performed on these images using the calculated responses. The deformed phantom was registered to the original phantom using an in-house developed software based on the Demons algorithm. The transfer matrix for each voxel was obtained and used to correlate the two sets of the reconstructed dose to generate a cumulative reconstructed dose on the original phantom. Forwardly calculated planning dose in the original phantom was compared to the cumulative reconstructed dose from EPID in the original phantom. The prescribed 200 cGy isodose lines showed little difference with respect to the "prostate" and "seminal vesicles", but appreciable difference (3%) was observed at the dose level greater than 210 cGy. In the rectum, the reconstructed dose showed lower volume coverage by a few percent than the plan dose in the dose range of 150 to 200 cGy. Through this study, the system of clinical application of reconstructed dose was successfully developed and demonstrated. The organ deformation simulated in this study resulted in small but observable dose changes in the target and critical structure.

Pyrotinib Combined with Vinorelbine in Patients with Previously Treated HER2-Positive Metastatic Breast Cancer: A Multicenter, Single-arm, Prospective Study

Kuikui Jiang,Ruoxi Hong,Wen Xia,Qianyi Lu,Liang Li,Jianhao Huang,Yanxia Shi,Zhongyu Yuan,Qiufan Zheng,Xin An,Cong Xue,Jiajia Huang,Xiwen Bi,Meiting Chen,Jingmin Zhang,Fei Xu,Shusen Wang 대한암학회 2024 Cancer Research and Treatment Vol.56 No.2

Purpose This study aims to evaluate the efficacy and safety of a new combination treatment of vinorelbine and pyrotinib in human epidermal growth factor receptor 2 (HER2)–positive metastatic breast cancer (MBC) and provide higher level evidence for clinical practice. Materials and Methods This was a prospective, single-arm, phase 2 trial conducted at three institutions in China. Patients with HER2-positive MBC, who had previously been treated with trastuzumab plus a taxane or trastuzumab plus pertuzumab combined with a chemotherapeutic agent, were enrolled between March 2020 and December 2021. All patients received pyrotinib 400 mg orally once daily plus vinorelbine 25 mg/m2 intravenously or 60-80 mg/m2 orally on day 1 and day 8 of 21-day cycle. The primary endpoint was progression-free survival (PFS), and the secondary endpoints included the objective response rate (ORR), disease control rate (DCR), overall survival, and safety. Results A total of 39 patients were enrolled. All patients had been pretreated with trastuzumab and 23.1% (n=9) of them had accepted trastuzumab plus pertuzumab. The median follow-up time was 16.3 months (95% confidence interval [CI], 5.3 to 27.2), and the median PFS was 6.4 months (95% CI, 4.0 to 8.8). The ORR was 43.6% (95% CI, 27.8% to 60.4%) and the DCR was 84.6% (95% CI, 69.5% to 94.1%). The median PFS of patients with versus without prior pertuzumab treatment was 4.6 and 8.3 months (p=0.017). The most common grade 3/4 adverse events were diarrhea (28.2%), neutrophil count decreased (15.4%), white blood cell count decreased (7.7%), vomiting (5.1%), and anemia (2.6%). Conclusion Pyrotinib plus vinorelbine showed promising efficacy and tolerable toxicity as second-line treatment in patients with HER2-positive MBC.