Objective To evaluate the accuracy of multiparametric imaging on the dual-source CT through acceptance and commissioning testing, and to provide a reference for standardized clinical application. Methods Both the adult and pediatric dual-source CT scanning modes were used to scan the electron density phantom, and identical multiparametric image reconstruction tasks were performed, including the conventional CT images, the mixed CT images, the virtual monoenergetic images, the iodine images, the electron density images, and the effective atomic number images. Results In the adult scanning mode, the virtual monoenergetic CT numbers showed the greatest difference for the cortical bone (1722 HU at 40 keV vs. 30 HU at 80 keV), with smaller differences observed for other materials as their atomic numbers decreased. The pediatric scanning mode exhibited a similar trend, with the largest difference occurring at 40 keV (1393 HU). In the adult scanning mode, the deviations between the theoretical and measured iodine concentration values were all within 5%, whereas in the pediatric scanning mode, the largest deviation was 15% for an iodine concentration of 2.0 mg/mL. For the electron density, the largest deviation between the theoretical and measured values occurred in the LN450 lung (9.18% in the adult scanning mode and 8.96% in the pediatric scanning mode); the deviations for the LN300 lung were all below 7.2%, for aluminum below 6.3%, and for other tissues within 3%. For the effective atomic number, the deviations between the theoretical and measured values were all within 5% in both scanning modes. Conclusion To ensure the accuracy and reproducibility of the dual-source CT applications, a comprehensive acceptance testing protocol should be established to guarantee the safety and precision of the CT localization process.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

【Objective】 To construct the secretory expression system of insect cells to express the secretory TSHR A subunit protein in the ovarian cells of Spotoma oryzae (sf9). 【Methods】 A recombinant plasmid containing the target protein was constructed, and then the positive bacmid was screened out by the blue and white spots experiment. The verified bacmid was transfected into SF9 insect cells to obtain recombinant baculovirus. The virus was amplified, and the titer level was detected by virus plaque assay. Finally, Western blotting was used to identify the expression of the recombinant protein and optimize the expression conditions. 【Results】 During the construction of the protein expression system, PCR identification and sequencing results confirmed the correctness of the sequences of the recombinant plasmid and the recombinant bacmid. After the transfection of the bacmid, the signs of virus budding were observed in sf9 cells. The virus was collected and amplified. The titer of P1 generation virus was 2×10⁷ pfu/m according to the plaque assay. The recombinant protein was identified by Western blotting and confirmed to be exogenous into the culture medium. The optimal condition for virus infection and protein expression was 72 h after the infection when the multiplicity of infection (MOI) was 1. 【Conclusion】 We constructed an insect cell expression system secreting TSHR 22-289 (55 ku), and the protein could be successfully glycolyzed. This system provides a preliminary basis for the construction and production of its industrial platform and also provides a useful tool for studies on TSHR protein and prevention of GO in the future.

Objective:To analyze the molecular mechanism of Zhenqi Fuzheng Capsules in the adjuvant treatment of AIDS by network pharmacology method and molecular docking technology.Methods:The active components and targets of Zhenqi Fuzheng Capsules were obtained through TCMSP, and the AIDS-related targets were obtained through GeneCards, OMIM and DrugBank databases. The intersection target PPI network was constructed through STRING 11.5 database, and Cytoscape 3.9.1 software was used for network topology analysis; Metascape database was used for GO function and KEGG pathway enrichment analysis of core targets; Cytoscape 3.9.1 was used to construct Zhenqi Fuzheng Capsules component-target-pathway network; Autodock Tools software was used to carry out molecular docking of core targets and active components.Results:Totally 31 active components and 180 targets of Zhenqi Fuzheng Capsules were screened out. TNF, IL6, AKT1, IL1B, TP53, VEGFA, RELA, EGFR and CASP3 were identified as the core targets. GO functional enrichment analysis obtained 1 436 biological processes, 53 cellular components, and 117 molecular functions. KEGG pathway enrichment analysis obtained 167 pathways, which were related to pathways in cancer, AGE-RAGE signaling pathway in diabetic complications, and IL-17 signaling pathway was closely related. Molecular docking results showed that core targets such as AKT1 and TNF had good binding activity to quercetin, kaempferol, and luteolin.Conclusion:The main active components of Zhenqi Fuzheng Capsules in the adjuvant treatment of AIDS are quercetin, kaempferol and luteolin, which may treat AIDS through the IL-17 signaling pathway.

Objective:To propose a markless patient setup workflow based on the optical surface monitoring system (AlignRT) and open-face mask immobilization for whole-course head tumor radiotherapy, assess the setup time and repositioning frequency of the proposed workflow, and conduct a comparative analysis of the differences, correlation, and consistency of the setup errors of the AlignRT and cone beam CT (CBCT) systems.Methods:A retrospective analysis was conducted for the data on the errors of 132 fractionated setup based on open-face mask immobilization of 33 head tumor patients. AlignRT-guided markless patient setup workflow was applied throughout the radiotherapy. Meanwhile, the body structures automatically generated by the treatment planning system were used as body references. The 6-degree-of-freedom (6DoF) setup errors (lateral, vertical, longitudinal, rotation, pitch, roll, and yaw directions), setup time, and repositioning frequency of the AlignRT and CBCT systems were recorded and analyzed. The Wilcoxon and Spearman analyses were used to statistically assess the differences and correlation of the setup errors of the two systems. Moreover, the Bland-Altman analysis was employed to evaluate the consistency of the two systems.Results:The 6DoF setup errors of CBCT were within the clinical tolerance (linear motions: -0.30 to 0.30 cm; rotational motions: -2.0° to 2.0°). The setup time and repositioning frequency of CBCT were (98 ± 31) s and 1.51% (2/132), respectively. There was no significant difference in setup errors between the two systems except those in x-axis ( Z = -3.11, P= 0.002), y-axis ( Z = -7.40, P<0.001), and Pitch ( Z= -4.48, P<0.001). There was a significant positive correlation between the setup errors along lateral ( rs = 0.47, P<0.001) and vertical ( rs = 0.29, P = 0.001) directions, rotation (Rtn; rs = 0.47, P<0.001), pitch (Pitch; rs = 0.28, P = 0.001) and roll (Roll; rs = 0.45, P<0.001) of the two systems. The 95% limits of agreement (95% LoA) of 6DoF setup errors were -0.12 to 0.09 cm, -0.07 to 0.17 cm, -0.19 to 0.20 cm, -1.0° to 0.9 °, -1.0° to 1.5°, and -0.9° to 1.0°, respectively. The 95% confidence interval (95% CI) of 95% LoA was -0.14 to 0.11 cm, -0.09 to 0.19 cm, -0.23 to 0.23 cm, -1.2° to 1.1°, -1.2° to 1.7°, and-1.0° to 1.1°, respectively, all of which were within the permissible error ranges. The 6DoF setup error difference of 3.41% (27/792< 5%) was beyond the 95% LoA. The maximum absolute differences of 6DoF setup errors within the 95% LoA were 0.12, 0.16, 0.19 cm, 0.9°, 1.5°, and 1.0°, respectively. Conclusions:The proposed markless setup workflow based on AlignRT combined with open-face mask immobilization for whole-course head tumor radiotherapy exhibits reasonable agreement and consistency with the patient setup using CBCT, with acceptable clinical efficiency. It can be applied to the first radiotherapy and the real-time monitoring of therapy to improve the safety and thus is of value in clinical applications.

Objective:To assess the three-dimensional dose distribution in radiotherapy plans using the structural similarity index(SSIM), compare the performance of SSIM with commonly used quality assessment indices, and develop a SSIM-based quality assessment method of multiple prescribed doses.Methods:The SSIM was introduced to providea quality score of various voxels by comparing actual and ideal three-dimensional dose data and combining the spatial location information of the voxels. Then the average value in a region of interest (ROI) was calculated as the quality score of the region. Fifty-three cases of cervical cancer were selected to analyze the correlation of the SSIM with the uniformity index (HI), conformity index (CI) of the dose distribution in various ROIs and to explore the capability of the SSIM to reflect the uniformity and conformity of dose distribution.Two types of quality defects were individually introduced into two of 53 radiotherapy plans. Then the two plans were compared with normal plans to characterize the response of the SSIM.Results:There was no correlation between HI and SSIM in positive lymph nodes(PGTVnd) due to the decrease in the HI sensitivity, while there was a significant negative correlation between them in regions where PGTVnd was removed from the planning target volume(PTV, R=-0.86, P<0.01). Meanwhile, there was a significant positive correlation between CI and SSIM in PGTVnd ( R=0.83, P<0.01). Therefore, the SSIM can be used to identify the artificial design defects in plans by determining abnormal dose gradients. Conclusions:Apart from reducing the defects of previous assessment parameters, the SSIM has the capability to assess the quality of radiotherapy plans by combining the uniformity and conformity of dose distribution and can provide accurate feedback on the spatial locations of quality defects.

Objective:To develope an automatic volumetric modulated arc therapy (VMAT) planning for rectal cancer based on a dose-prediction model for organs at risk(OARs) and an iterative optimization algorithm for objective parameter optimization.Methods:Totally 165 VMAT plans of rectal cancer patients treated in Peking University Cancer Hospital & Institute from June 2018 to January 2021 were selected to establish automatic VMAT planning. Among them, 145 cases were used for training the deep-learning model and 20 for evaluating the feasibility of the model by comparing the automatic planning with manual plans. The deep learning model was used to predict the essential dose-volume histogram (DVH) index as initial objective parameters(IOPs) and the iterative optimization algorithm can automatically modify the objective parameters according to the result of protocol-based automatic iterative optimization(PBAIO). With the predicted IOPs, the automatic planning model based on the iterative optimization algorithm was achieved using a program mable interface.Results:The IOPs of OARs of 20 cases were effectively predicted using the deep learning model, with no significantly statistical difference in the conformity index(CI) for planning target volume(PTV)and planning gross tumor volume(PGTV)between automatic and manual plans( P>0.05). The homogeneity index (HI) of PGTV in automatic and manual plans was 0.06 and 0.05, respectively( t=-6.92, P< 0.05). Compared with manual plans, the automatic plans significantly decreased the V30 for urinary bladder by 2.7% and decreased the V20 for femoral head sand auxiliary structure(avoidance)by 8.37% and 15.95%, respectively ( t=5.65, 11.24, P< 0.05). Meanwhile, the average doses to bladder, femoral heads, and avoidance decreased by 1.91, 4.01, and 3.88 Gy, respectively( t=9.29, 2.80, 10.23, P< 0.05) using the automatic plans. The time of automatic VMAT planning was (71.49±25.48)min in 20 cases. Conclusions:The proposed automatic planning based on dose prediction and an iterative optimization algorithm is feasible and has great potential for sparing OARs and improving the utilization rate of clinical resources.

The American Transplant Congress (ATC) is an influential academic congress in the field of organ transplantation. In this article, the hotspots of liver transplantation in 2020 ATC were summarized, including the latest research progress in donor liver procurement and quality assessment, donor liver preservation and ischemia-reperfusion injury (IRI), liver transplantation for hepatocellular carcinoma and other hepatic malignancies, complications after liver transplantation, transplantation immunology, perioperative management and donor-derived infection, pediatric liver transplantation and cell therapy, etc.

Objective:To solve the problems in intensity-modulated radiation therapy (IMRT) planning, such as large labor cost and high dependence on the experience of physicists and great inconsistency in the quality of plan, and to discuss an unsupervised automatic treatment planning procedure of IMRT.Methods:The eclipse scripting application programming interface (ESAPI) within the Eclipse treatment planning system (TPS) 15.6 and optimization parameters tree search algorithm (OPTSA) were used to emulate and realize the whole planning process. Interacted with the TPS through ESAPI, relevant dosimetric parameters were input and output. The OPTSA evaluated the plan qualities based on dosimetric parameters of the targets and organs at risk (OARs) and iteratively adjusted the optimization objective parameters to achieve a progressively improving IMRT plan. In order to verify the effectiveness of the automatic planning, twenty historical rectum cancer cases were selected from the clinical database, and the dose distribution and specific dosimetric parameters were compared between the plans generated by the OPTSA and the manual plans under the same constraints.Results:All the auto plans have met clinical requirements. Furthermore, 90% and 10% of the auto plans were deemed as clinically improved and equally compared with the manual plans, respectively. The average CI for the PTV was 0.88 and 0.80 for the auto and manual plans respectively. Compared with the manual plans, the mean doses of all the OARs in the auto plans were reduced by 11% in average. The average elapsed time of automatic planning and manual planning was (28.15±3.61) and (36.7±4.6) min, respectively.Conclusions:The plans created by the proposed algorithm have been shown to be at least as good as the manual plans. In addition, this method can shorten the labor time in plan designing while ensuring the plan quality and consistency of the plan.