1.Impact of tumor treating fields transducer arrays on concurrent radiotherapy dosimetry
Keqiang WANG ; Jie CHEN ; Jianbo JIAN ; Peng WANG ; Xinshan ZHANG ; Hongyang ZHANG ; Wenxue ZHANG
Chinese Journal of Radiation Oncology 2024;33(5):438-445
Objective:To investigate the dosimetric impact of tumor treating fields (TTF) transducer arrays on concurrent radiotherapy for patients with glioblastoma (GBM).Methods:A strategy was developed to accurately simulate the dosimetric impact of TTF arrays on radiotherapy, including the establishment of accurate auto-segmentation technique for TTF arrays, determination of the relative electron density (RED) of the transducer arrays and validation of the dose calculation accuracy in the treatment planning system (TPS) for TTF arrays. Based on this strategy, the dosimetric impact of TTF arrays on clinical treatment plans of 10 patients with GBM was evaluated. Furthermore, the dosimetric comparison between the clinical plans with different beam energies were investigated when TTF arrays were used. The methods of analysis of variance were paired t-test or Wilcoxon signed-rank test based on whether the differences followed a normal distribution. Results:The auto-segmentation technique for TTF arrays was established by designing a workflow in Mim software and achieved a Dice coefficient of 0.93 and a Jaccard index of 0.87 compared to the standard contours. The RED of TTF arrays was 3.3 which was derived from the comparison between the measured and simulated percentage depth dose (PDD) with and without TTF arrays on phantom. Measured and calculated dose distributions were compared using the 2D gamma analysis. The gamma passing rates on the coronal plane of 4 mm and 5.1 cm depth were 96.64% and 94.55% at the criteria of 3% /3 mm, indicating that the calculation accuracy of algorithm in TPS for TTF arrays could meet clinical requirements. In the clinical treatment plans of patients with GBM, the presence of TTF arrays caused a mean reduction of planning target volume (PTV) dose of approximately 1%, and an increase in scalp dose of approximately 5%, with minimal impact on other organs at risk (OAR). The 10 MV plans resulted in a higher dose of PTV by 0.3% and lower dose of scalp by approximately 3% compared to the 6 MV plans, when considering TTF arrays.Conclusions:The accurate simulation strategy for the dosimetric impact of TTF arrays on radiotherapy established in this study ensures the accuracy and precision of the calculations. In TTF therapy combined with concurrent radiotherapy for GBM, TTF arrays have slight effect on PTV dose, but significantly increase scalp dose. High-energy beam can reduce the impact of TTF arrays.
2.Plan quality comparison between coplanar and non-coplanar VMAT for the whole brain radiotherapy with hippocampus and hypothalamic-pituitary axis sparing
Keqiang WANG ; Jie CHEN ; Jianbo JIAN ; Peng WANG ; Xinshan ZHANG ; Hongyang ZHANG ; Wenxue ZHANG
Chinese Journal of Radiation Oncology 2024;33(7):634-641
Objective:To compare the plan quality between coplanar and non-coplanar volumetric modulated arc therapy (co-VMAT and nco-VMAT) techniques for the whole brain radiotherapy with hippocampus and hypothalamic-pituitary (HT-P) axis sparing.Methods:A total of 15 patients who underwent prophylactic cranial irradiation in Tianjin Medical University General Hospital from November 2021 to August 2023 were retrospectively selected. The hippocampus and HT-P axis were delineated according to Radiation Therapy Oncology Group (RTOG) 0933 and contouring guidelines for hypothalamus. Co-VMAT and nco-VMAT plans were generated for each patient with a prescription dose of 30 Gy in 10 fractions. Then, dosimetric parameters, plan robustness, plan complexity, and delivery efficiency for both plans were compared using paired t-test. Results:Both co-VMAT and nco-VMAT plans could achieve dosimetric objectives. There were no significant differences in D 2%, D 95% and conformity index (CI) of planning target volume (PTV) between the two plans. The D 98% and homogeneity index (HI) of PTV in co-VMAT showed a slight inferiority compared to that in nco-VMAT (D 98%: 26.37 Gy vs. 26.96 Gy, P=0.001; HI: 0.25 vs. 0.24, P=0.002). The D min of bilateral hippocampus in co-VMAT were 8.55 Gy (left) and 8.32 Gy (right), which were lower than 9.31 Gy (left) and 9.26 Gy (right) in nco-VMAT. In addition, the D mean of the hypothalamus and pituitary in the co-VMAT plan were lower than those in the nco-VMAT plan (hypothalamus: 11.54 Gy vs. 12.27 Gy; pituitary: 11.72 Gy vs.12.1 Gy, both P<0.001). The doses to the hippocampus and HT-P axis were highly sensitive to errors in both co-VMAT and nco-VMAT plans, while the sensitivity of dose to errors in the PTV and other organs at risk was low. The co-VMAT plan had lower complexity compared to the nco-VMAT plan, with γ passing rate at 3%/3 mm criteria of 99.06%±0.60% and 98.05%±2.89%, respectively. The average beam-on time of the co-VMAT plan was 4.8 min, approximately 2/3 of the time for nco-VMAT, while the average treatment time was 6.3 min, approximately half of the treatment time for nco-VMAT. Conclusions:Both co-VMAT and nco-VMAT can achieve hippocampus and HT-P axis sparing in the whole brain radiotherapy. In the co-VMAT plan, the D 98% of the PTV is slightly smaller, but it provides better protection for the hippocampus and HT-P axis. The doses to the hippocampus and HT-P axis are sensitive to errors in both plans. However, the co-VMAT plan has lower complexity, higher delivery efficiency, and is more suitable for clinical treatment.
3.Projection domain and image domain joint learning reconstruction network for reconstructing chest limited angle CT images
Jie CHEN ; Keqiang WANG ; Jianbo JIAN ; Peng WANG ; Jun WU ; Wenxue ZHANG
Chinese Journal of Medical Imaging Technology 2024;40(9):1410-1416
Objective To observe the value of dual domain(projection domain and image domain)joint learning reconstruction network(DDRNet)for reconstructing chest limited angle CT images.Methods Totally 4 300 chest enhanced CT images of 65 patients with chest tumors were retrospectively enrolled and reconstructed with DDRNet,and 3D and 2D projection information fusion were performed.The reconstruction effect of DDRNet was evaluated and compared with that of single domain reconstruction and filtered back projection(FBP),residual encoder-decoder convolutional neural network(RED-CNN),Resnet and deconvolution network(RDN),as well as of generative adversarial network(GAN).Results The peak signal to noise ratio(PSNR)of DDRNet reconstructed images tended to stabilize after approximately 60 iterations,while the projection domain and image domain learning networks tended to stabilize after approximately 90 and 80 iterations.After stable training,compared to the projection domain learning network,the fluctuation of output results of DDRNet and image domain learning networks were less.After 200 rounds of training,PSNR of DDRNet reconstructed images was significantly higher than that of projection domain and image domain learning networks.The quality of DDRNet reconstructed image was significantly better than that of FBP,RED-CNN,RDN and GAN.Conclusion DDRNet could be used to effectively reconstruct high-quality chest limited angle CT images.
4.Research progress in culture, purification and isolation of synovial type A cells in vitro and their biological functions
Cheng WAN ; Yintao LEI ; Keqiang WANG
International Journal of Biomedical Engineering 2023;46(4):370-374
The temporomandibular joint (TMJ) is surrounded by a joint capsule, the smooth inner layer of which is called the synovial membrane. Synovium is involved in various intraarticular diseases, and it is a key area of joint disease. Synovial type-A cells are located in the lining layer of the synovial membrane, mostly on the side of the membrane close to the joint cavity. They have a strong phagocytic effect, and their main role is to remove the degradation products of the intra-articular and extracellular matrix. Various intra-articular diseases will affect the synovium, which is the key area of joint disease. The method of cell culture in vitro can effectively simulate the growth environment of cells in vivo and can accurately understand the effects of single and multiple factors on synovial cells, which has become a basic research method. In this review paper, the latest research progress in human temporomandibular joint type-A synoviocytes is reviewed from the aspects of cell origin, in vitro culture, cell purification, and cell biological function.
5.Development dilemmas and countermeasures of the cross regional loose medical alliances in the Yangtze River Delta
Keqiang ZUO ; Longjun HU ; Jumi XU ; Mingping QIAN ; Chenchen WANG ; Yanmeng WU ; Yi LIU ; Xiuzhi CHEN ; Yingchuan LI ; Hongxiang FEI
Chinese Journal of Hospital Administration 2023;39(11):799-803
The cross regional loose medical alliance is an important carrier in the current integrated development process of medical services in the Yangtze River Delta region. Smith policy implementation process model was used to analyze the development difficulties of cross regional loose medical alliances from idealized policies, policy implementation institutions, policy target groups, and policy implementation environment. Such medical alliances were formed under the background of integrated development in the Yangtze River Delta, with Shanghai′s tertiary public hospitals as leading units and medical institutions in Jiangsu, Zhejiang, and Anhui provinces as member units. Analysis showed that the policies for such medical alliances development had not yet clearly defined the organizational management mode, operational mechanism, and implementation path, and the corporate governance structure of medical alliance was immature; The policy implementation agencies were relatively lagging behind in the support of special funds and the formulation of related supporting policies; Participation of policy target groups was insufficient and their incentive mechanisms was imperfect; There were problems in the policy implementation environment, namely inconsistent medical and health service regulations and systems in different regions, different health financing capabilities of local governments, insufficient coordination of medical institution management concepts, and a lack of unified standards in information systems. Based on the above difficulties, this study proposed to strengthen the development planning and layout of cross regional loose medical alliances, and improve the corporate governance structure; To strengthen the government′s main responsibility and improving policy implementation capabilities; To improve the internal cooperation and operation mechanism of cross regional loose medical alliances, and enhance the sense of identity of the target group; To optimize the policy implementation environment and implement various support measures, so as to provide references for further promoting the coordinated development of high-quality medical resources in the Yangtze River Delta region.
6.Research on automatic segmentation of tumor target of lung cancer in CBCT images by multimodal style transfer technology based on deep learning
Jie CHEN ; Keqiang WANG ; Jianbo JIAN ; Peng WANG ; Zhichao GUO ; Wenxue ZHANG
Chinese Journal of Radiation Oncology 2022;31(1):43-48
Objective:Due to the low contrast between tumors and surrounding tissues in CBCT images, this study was designed to propose an automatic segmentation method for central lung cancer in CBCT images.Methods:There are 221 patients with central lung cancer were recruited. Among them, 176 patients underwent CT localization and 45 patients underwent enhanced CT localization. The enhanced CT images were set as the lung window and mediastinal window, and elastic registration was performed with the first CBCT validation images to obtain the paired data set. The CBCT images could be transformed into" enhanced CT" under the lung window and mediastinal window by loading the paired data sets into cycleGAN network for style transformation. Finally, the transformed images were loaded into the UNET-attention network for deep learning of GTV. The results of segmentation were evaluated by Dice similarity coefficient (DSC), Hausdorff distance (HD) and the area under the receiver operating characteristic curve (AUC).Results:The contrast between tumors and surrounding tissues was significantly improved after style transformation. The DSC value of cycleGAN+ UNET-attention network was 0.78±0.05, HD value was 9.22±3.42 and AUC value was 0.864, respectively.Conclusion:The cycleGAN+ UNET-attention network can effectively segment central lung cancer in CBCT images.
7.Practice and enlightenment of the construction of multi-agent collaborative loose medical alliance under the background of Yangtze River Delta integration
Mingping QIAN ; Xiaoyuan ZHOU ; Longjun HU ; Wenyi CHEN ; Hongfei TENG ; Jue WANG ; Aimin WANG ; Wenrong GU ; Peiqin NIU ; Yingchuan LI ; Keqiang ZUO
Chinese Journal of Hospital Administration 2022;38(6):411-415
Health service is an important part of the integrated development of the Yangtze River Delta. Taking the cooperation practice between Shanghai Tenth People′s Hospital and Suzhou Yinshanhu Hospital as an example, this article introduced the multi-agent cooperation mode of the loose medical alliance including the government, urban hospitals and cross provincial grassroots medical institutions. Among them, the local government provided policy, fund guarantee and guidance, the urban hospital exported management ideas, medicine talents and technologies, and the primary hospital conducted dual training by inviting in and going out to achieve double growth. Through the high gap cooperation between tertiary hospital and primary hospital, Yinshanhu hospital had been comprehensively developed. The loose medical alliance with multi subject coordination and cross region could give full play to the advantages of the loose healthcare alliance mode, achieve multi-win, and have reference significance for promoting the regional integration of medical and health services in the Yangtze River Delta.
8.Tetracycline natural products: discovery, biosynthesis and engineering.
Haiyan WANG ; Lijun WANG ; Keqiang FAN ; Guohui PAN
Chinese Journal of Natural Medicines (English Ed.) 2022;20(10):773-794
Tetracycline (TC) natural products possess a variety of remarkable bioactivities and diverse structures. They are an important and fertile source for developing novel drugs. As one of the most successful drug families, TC antibiotics have been in clinical use for over seven decades, and continue to make an important contribution to human health nowadays. To date, studies on TC natural products and their biosynthesis have revealed numerous novel biochemical mechanisms and regulatory elements, which facilitates the rational metabolic engineering studies for generating novel bioactive TC analogs and inspires the development of new synthetic biology tools. In this review, we provide a comprehensive overview on the discovery, biosynthesis, and engineering of the existing TC natural products. These analyses will be of great value for the discovery, design and development of novel TC drugs in the future.
Humans
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Biological Products/metabolism*
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Anti-Bacterial Agents
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Metabolic Engineering
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Synthetic Biology
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Tetracycline
9.Development of a
Yiying YANG ; Qingqing SUN ; Yang LIU ; Hanzhi YIN ; Wenping YANG ; Yang WANG ; Ying LIU ; Yuxian LI ; Shen PANG ; Wenxi LIU ; Qian ZHANG ; Fang YUAN ; Shiwen QIU ; Jiong LI ; Xuefeng WANG ; Keqiang FAN ; Weishan WANG ; Zilong LI ; Shouliang YIN
Journal of Zhejiang University. Science. B 2021;22(5):383-396
10.Expression of γδT and CD4 + CD25 + T cells in peripheral blood of HIV-infected patients/AIDS patients and their correlation
Nange ZHAO ; Jianping ZHANG ; Tingting ZHANG ; Yin YIN ; Keqiang WANG
Chinese Journal of Microbiology and Immunology 2021;41(7):524-530
Objective:To understand the expression levels of γδT cells and CD4 + CD25 + regulatory T cells in the peripheral blood of HIV-infected/AIDS patients, and explore the correlation and possible relationship between γδT cells and CD4 + CD25 + regulatory T cells in the progression of HIV infection/AIDS Mechanism. Methods:Immunofluorescent monoclonal antibody labeling technology and flow cytometry were used to detect 12 cases of AIDS, 19 cases of intermediate HIV infection, 15 cases of early HIV infection, and 30 cases of healthy physical examination in peripheral blood CD3 + T cells and CD4 + The expression levels of T cells, CD8 + T cells, γδT cells, CD4 + CD25 + regulatory T cells; Pearson was used to analyze the correlation between γδT cells and CD4 + CD25 + regulatory T cells. Results:The expression (Mean± SD, %) of γδT cells in the peripheral blood of the AIDS group, the mid-stage HIV infection group, the early HIV infection group and the healthy control group were: 4.46±1.37, 3.59±0.67, 3.12±0.33, 1.73±0.36, group The time ratio, F=6.091, P=0.018. The expression (Mean± SD, %) of CD4 + CD25 + regulatory T cells in the peripheral blood of the AIDS group, the mid-stage HIV infection group, the early HIV infection group, and the healthy control group were: 10.28±1.94, 7.37±1.03, 6.68±0.58, 4.03±0.82, ratio between groups, F=13.568, P=0.002. The comparison of γδT and CD4 + CD25 + regulatory T cells among the four groups is statistically significant, AIDS group>HIV mid-infection group>HIV early infection group>control group. In terms of correlation, γδT, CD4 + CD25 + regulatory T cells are negatively correlated with CD4 + T cells ( r value are -0.982, -0.712, P value are 0.001, 0.002, respectively), and positively correlated with CD8 + T cell counts ( r value are 0.873 , 0.809, P value are 0.000 and 0.000 respectively); γδT cells are positively correlated with CD4 + CD25 + regulatory T cells ( r=0.911, P=0.000). Conclusions:HIV infection induces the proliferation of γδT cells and CD4 + CD25 + regulatory T cells, both of which participate in the immune response caused by HIV infection. γδT cells are positively correlated with CD4 + CD25 + regulatory T cells, and the two may have a synergistic effect.

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