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Objective:To analyze the differences in dosimetric quality and plan complexity of volumetric modulated arc therapy (VMAT) plans based on Halcyon 2.0 and Truebeam for different treatment sites of the patients.Methods:Halcyon 2.0 VMAT plans in head & neck, chest, abdomen, and pelvis treatment sites of 49 cases were retrospectively selected and the VMAT plans were re-designed based on Truebeam with the same optimization parameters. The differences in dosimetric metrics and plan complexity between the two types of plans were compared and analyzed. P<0.05 was considered as statistically significant. Results:In terms of PTV, Halcyon 2.0 plans showed better homogeneity index (HI), conformal index (CI) in the head & neck and chest. Besides, Halcyon 2.0 plans yielded better D 98% and CI in the abdomen and better D 2% in the pelvis. For organs at risk (OAR), the D 20% and D mean of bilateral lungs, and D meanof heart for Halcyon 2.0 plans in the chest were lower than those for Truebeam plans (all P<0.05). For the complexity metrics, the median average aperture area variability (AAV) of Halcyon 2.0 plans in the head & neck, abdomen and pelvis were 0.414, 0.425 and 0.432, which were better than 0.385, 0.368 and 0.361 of Truebeam plans in the corresponding sites, respectively. In the abdomen and pelvis, Halcyon 2.0 plans showed better median modulation complexity score (MCS) than Truebeam plans (0.320 vs. 0.268, 0.303 vs. 0.282; both P<0.05). The median small aperture score (SAS) for all plans of Halcyon 2.0 were better than that of Truebeam plans (all P<0.05), and the median plan average beam area (PA) of all plans of Halcyon 2.0 were larger than that of Truebeam plans (all P<0.05). Conclusions:Compared with conventional fractionated VMAT plans based on Halcyon 2.0 and Truebeam, Halcyon 2.0 plans have similar or even better dosimetric quality. However, Halcyon 2.0 plans have lower plan complexity, which makes it an advantage in clinical application.
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Objective:To study the role of a novel brain-derived peptide hypoxic-ischemic brain damage associated peptide (HIBDAP) in regulating pyroptosis of oxygen-glucose deprived (OGD) microglia.Methods:The sequence of HIBDAP was coupled with the sequence of cell-penetrating peptide transactivator of transcription (TAT) to form TAT-HIBDAP. Fluorescein isothiocyanate (FITC) labeled TAT-HIBDAP was added to microglia cells and observed under fluorescence microscope. Microglia cells were treated with different concentrations of TAT-HIBDAP (1, 5, 10, 20 μmol/L) and then OGD process. Cell pyroptosis was analyzed using lactate dehydrogenase (LDH) assay. The concentration of TAT-HIBDAP with the most prominent inhibiting effects was determined and selected for subsequent experiments. The pyroptosis morphology of the control group, the OGD group and the HIBDAP group (5 μmol/L TAT-HIBDAP+OGD) was observed using transmission electron microscope. The mRNA and protein expression of NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasomes were examined using real-time quantitative PCR and Western Blot analysis.Results:Fluorescence microscope showed FITC-labeled TAT-HIBDAP could successfully enter microglia cells. Compared with the OGD group, low concentrations of TAT-HIBDAP (1, 5, 10 μmol/L) could significantly reduce microglia pyroptosis and the concentration of 5 μmol/L showed the most prominent effects. Compared with the control group, OGD group showed typical pyroptosis morphology and HIBDAP group showed significantly improved morphology. The mRNA and protein expression of NLRP3 inflammasomes in the OGD group were significantly higher than the control group and also the HIBDAP group.Conclusions:The novel brain-derived peptide HIBDAP may reduce the expression of NLRP3 inflammasomes and inhibit the pyroptosis of OGD microglia.
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BACKGROUND@#As the efficacy of programmed cell death-1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors combined with chemotherapy in curing breast cancer is still controversial, this meta-analysis compares the efficacy and safety of PD-1/PD-L1 inhibitors combined with chemotherapy and chemotherapy alone in the treatment of breast cancer, which provides guidance for the clinical treatment.@*METHODS@#Relevant studies published as of April 2022 in the various databases including EMBASE, PubMed, and Cochrane Library were selected. Randomized controlled trials (RCTs) in which control patients underwent chemotherapy alone and experimental group patients underwent combination chemotherapy and PD-1/PD-L1 inhibitor treatment were included in this investigation. Investigations without complete information, researches from which information could not be extracted, duplicate articles, animal studies, review articles, and systematic reviews were excluded. STATA 15.1 was employed for all statistical analyses.@*RESULTS@#In total, eight eligible studies were identified, revealing that combination chemotherapy and PD-1/PD-L1 inhibitor treatment was linked to significant increases in progression-free survival (PFS) relative to chemotherapy alone (hazard ratio [HR] = 0.83, 95% confidence interval [CI]: 0.70-0.99, P = 0.032) but not overall survival (HR = 0.92, 95% CI: 0.80-1.06, P = 0.273). Pooled adverse event rates were also increased within the group of combination treatment relative to the chemotherapy group (risk ratio [RR] = 1.08, 95% CI: 1.03-1.14, P = 0.002). Specifically, nausea rates were lesser within the group of combination treatment relative to the group of chemotherapy (RR = 0.48, 95% CI: 0.25-0.92, P = 0.026). Subgroup analyses indicated that the PFS of patients who underwent combination atezolizumab or pembrolizumab and chemotherapy treatment were substantially longer than those of patients who underwent chemotherapy alone (HR = 0.79, 95% CI: 0.69-0.89, P ≤0.001; HR = 0.79, 95% CI: 0.67-0.92, P = 0.002).@*CONCLUSIONS@#The pooled results suggest that combination chemotherapy and PD-1/PD-L1 inhibitor treatment approaches help prolong PFS in breast cancer patients, but have no statistically significant effect on overall survival (OS). Additionally, combination therapy can significantly improve complete response rate (CRR) compared with chemotherapy alone. However, combination therapy was associated with greater rates of adverse events.
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Humans , B7-H1 Antigen/antagonists & inhibitors , Drug Therapy, Combination , Immune Checkpoint Inhibitors/therapeutic use , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Breast Neoplasms/drug therapyABSTRACT
Objective:To compare the effectiveness and safety of laparoscopic hepatectomy (LH) versus radiofrequency ablation (RFA) in treatment of hepatocellular carcinoma (HCC).Methods:The medical literatures on LH and RFA for HCC were searched in PubMed, Web of Science, Embase, VIP, Wanfang, CNKI and other electronic databases. The retrieval date was from database construction to June 7, 2021. According to the inclusion and exclusion criteria, studies were extracted by two authors, and Revman 5.3 software was used to conduct a meta-analysis to compare differences in operation time, blood loss, length of hospital stay, total complications, overall survival and disease-free survival outcomes between the LH group and the RFA group.Results:Of 3 690 patients who were included in 32 studies, there were 1 708 patients in the LH group and 1982 patients in the RFA group. Meta-analysis showed that compared with the LH group, the RFA group had significantly shorter surgical duration ( MD=-86.41, 95% CI: -116.21--56.60), less blood loss ( MD=-213.22, 95% CI: -273.43--153.00), shorter hospital stay ( MD=-3.23, 95% CI: -4.13--2.32), and lower incidence of complications ( OR=0.33, 95% CI: 0.26-0.43). However, local recurrence rate was significantly higher ( OR=1.83, 95% CI: 1.38-2.41). (All P<0.05). The 5-year survival rate of the LH group was significantly better than the RFA group ( OR=0.68, 95% CI: 0.51-0.90, P=0.008). Conclusion:LH provided better overall survival outcomes and lower local recurrence rates than RFA in HCC patients.
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Objective:To investigate the current status of radiotherapy personnel and equipment in China, and to provide data basis for scientific allocation and effective use of radiotherapy equipment during the 14 th Five-year Plan period. Methods:From October to December 2020, a group of experts from China Association of Medical Equipment carried out an online questionnaire investigating the basic situation of radiotherapy in China, and the contents of the survey include radiotherapy centers, professional personnel, equipment, technology, equipment utilization rate, forecast of personnel and equipment in the next five years, etc. The data were reviewed by provincial medical societies/associations.Results:There were 1538 radiotherapy centers and 32978 radiotherapy professionals in Mainland China, including 18966 radiotherapy physicians, 4475 physicists and 9537 technicians. There were 2139 linear accelerators, 57 cobalt 60 accelerators, 457 afterloaders, 6 proton/heavy ion machines, 1034 conventional 2D simulators, 1208 CT simulators, and 89 MR simulators. 1459 centers can provide 3D conformal radiotherapy, 1256 centers can deliver intensity-modulated radiotherapy, 514 centers can offer volumetric modulated arc therapy, 422 centers can provide brachytherapy. According to the estimated data reported by the participating centers, in the next five years, the demand of professionals and machines will be increased by 4868 radiotherapy physicians, 2078 physicists and 3796 technicians, and 994 linacs, 896 CT simulators, 313 MR simulators and 54 proton heavy ions.Conclusions:The radiotherapy industry in China grows fast. During the 14 th Five-Year Plan period, the radiotherapy industry still has strong market demand as well as increase demand of personnel and equipment. Strengthening the market competitiveness of domestic radiotherapy enterprises, improving the equipment utilization rate in primary hospitals, providing comprehensive and systematic training and promoting standardized clinical application can resolve the issues of the lack and unbalanced distribution of radiotherapy resources, and maintain the fast and sustainable development of radiotherapy in China.
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Objective:To evaluate and summarize the teaching effect of" New Technology of Radiotherapy and Oncology" in the form of questionnaire, understand the degree of demand for the course of all kinds of medical students and improve the teaching contents and methods.Methods:The course of" New Technology of Radiotherapy and Oncology" was a specialized elective course in Peking Union Medical College. After two rounds of teaching practices, we evaluated the students participating in the course or non-course participants by anonymous questionnaire. The questionnaire items include the course content, setting, teachers and improvement suggestions.Results:A total of 73 questionnaires were sent out, and the recovery rate was 100%. Among them, 52(71%) were from students who chose the courses. 83% of the students" strongly agree" that the teaching content of this course is the latest development, the latest achievement or the problem to be solved, 94% were" satisfied" or" very satisfied" with their learning effect, and 92% and 83% were satisfied with the teachers and teaching plan, respectively. After taking the course, students rated" broadening of mind" (96%) as the biggest gain, followed by" facilitating interdisciplinary collaboration" (79%). 86% of the non-course participants felt the need to supplement the existing curriculum with new techniques in oncology radiotherapy, hoping that the curriculum would" broaden the mind" (76%), improve clinical application (81%) and facilitate interdisciplinary collaboration (71%).Conclusion:The questionnaire results show that the teaching practice of this course covers the different needs of all kinds of students, which is worthy of implementation and further improvement.
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Objective:To study the clinical feasibility and advantages of the RapidPlan module based on Halcyon 2.0 ring medical linear accelerator in the design of volumetric modulated arc therapy (VMAT) plans after cervical cancer surgery.Methods:The data of 98 clinical cervical cancer cases were selected from the database, and VMAT artificial radiotherapy plans were designed based on Halcyon 2.0. Then, the designed plans were imported into the RapidPlan module to train the module for a prediction model with high goodness of fit. Another 20 patients after cervical cancer surgery were selected as the validation set to compare the differences in dosimetry, plan consistency, and plan execution efficiency between the manual plans and RapidPlan automatic plans.Results:The RapidPlan automatic plans could obtain dose distribution of target volume and organs at risk with the same quality as the manual plans. The RapidPlan automatic plans provided slightly inferior protection of the femoral head but superior protection of the spinal cord compared to the manual plans, and the difference was statistically significant ( t = 4.71, P<0.001). The average MU of the RapidPlan automatic plans was 687.46, which was lower than that of the manual plan (815.34), and the difference was statistically significant ( t = 6.09, P < 0.05). The portal dosimetry (PD) verification revealed that the average γ passing rate (1 mm/1%) of the RapidPlan automatic plans was 89.48%and that of the manual plans was 88.22%, and the difference was statistically significant ( t = 3.35, P < 0.05). Conclusion:RapidPlan automatic plans based on the Halcyon 2.0 platform can meet the clinical needs of the VMAT program for cervical cancer and has certain advantages.
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Objective: To analyze the classification and functions of cell subsets in laryngeal carcinoma and metastatic lymph nodes, and to explore the evolution trajectory of epithelial cells to tumor cells. Methods: Single-cell RNA sequencing was performed on 5 cases of laryngeal cancer, matched metastatic lymph nodes and 3 normal tissues. Patients were admitted to Ningbo Medical Center Lihuili Hospital from October 22, 2019 to December 16, all patients were male, aged 53-70 years old. Cell subsets of the above-mentioned tissues were analyzed by the Seurat, and the biological functions of cell subpopulation were investigated by functional enrichment analysis. Malignant epithelial cells were identified using copy number variation (CNV). The evolutionary trajectory of epithelial cells to cancer cells was analyzed by cell trajectory analysis, and cancerous transitional cells were identified. The highly expressed genes in transitional cells were analyzed by the FindAllMarker of the Seurat and verified by immunohistochemistry. Results: A total of 66 969 high-quality cells were obtained in 9 major clusters: epithelial cells, T cells, B cells, fibroblasts, endothelial cells, myeloid cells, mast cells, plasmacytoid dendritic cells and nerve cells. The first 5 cell clusters were divided into 8, 6, 4, 3 and 2 subgroups, respectively. Four epithelial cell subsets (C0, C1, C2 and C5) were derived from tumor tissues and metastatic lymph nodes, and had high levels of CNV and tumor cell content. Cell trajectory analysis showed that the evolution trajectory of epithelial cells was from normal epithelial subpopulation C4 to early cancerous cell population C0, which differentiated into three major malignant cell subsets C1, C3, and C5. Epithelial cell C0 may represent the transitional cell population of carcinogenesis, and were enriched in biological processes such as epithelial-mesenchymal transformation and angiogenesis. C0 highly expressed sulforaphane (SFN) which may be related to the occurrence and development of cancer. Immunohistochemistry confirmed that SFN was highly expressed in tumor tissues and metastatic lymph nodes compared with paracancerous tissues. Conclusion: Single-cell sequencing may be used to elucidate the diversity of cells and functions in laryngeal carcinoma tissues and metastatic lymph nodes, and cell population C0 plays a key role in the evolution of cells.
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Aged , Humans , Male , Middle Aged , Carcinoma, Squamous Cell/pathology , DNA Copy Number Variations , Endothelial Cells/pathology , Laryngeal Neoplasms/pathology , Lymph Nodes/pathologyABSTRACT
The clinical data of a newborn with Kleefstra syndrome combined with SLC2A1 gene mutation in the Department of Newborn Infants, Children′s Hospital of Nanjing Medical University were retrospectively analyzed.The laboratory examination, genetic characteristics, diagnosis and treatment progress were analyzed.This is the first report of a newborn with Kleefstra syndrome combined with SLC2A1 gene mutation, presenting with an early-onset epilepsy.Gene analysis is the most reliable method to make a definitive diagnosis.
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Objective:To investigate the role of follicular helper T(Tfh) cells and galactose deficiency IgA 1(Gd-IgA 1) in the children that were suffering from Henoch-Sch?nlein purpura(HSP) and Henoch-Sch?nlein purpura nephritis(HSPN)and the correlation between them. Methods:According to the presence or absence of renal injury, 62 children with HSP were divided into HSP group with 32 children and HSPN group with 30 children.Twenty children who underwent physical examination at outpatients were known as the healthy control group.Flow cytometry was used to measure the proportion of Tfh(CD4 + CXCR5 + PD-1 + ) in peripheral blood.Immunoturbidimetry and ELISA were used to measure the serum levels of IgA 1 and Gd-IgA 1 respectively. Results:(1) The proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1 in both HSP group and HSPN group had significantly increased than those in healthy control group( P<0.01). Compared result of the HSPN group with HSP group, the proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1 in HSPN group were higher than that in HSP group( P<0.05). (2) In the HSPN group, the proportion of peripheral blood Tfh cells and the serum levels of Gd-IgA 1 in group of renal pathology ≥ grade Ⅲ and heavy proteinuria were significantly elevated compared with group of renal pathology < grade Ⅲ and non-heavy proteinuria(<0.01). (3) In the healthy control group, the serum levels of Gd-IgA 1 was positively correlated with the proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1( P<0.05). Conversely, a non-positive correlation was shown in HSP and HSPN groups( P>0.05). Conclusion:The excessive activation of Tfh cells and the serum levels of Gd-IgA 1 may be one of the pathogenesis of HSP/HSPN, the degree of increment of the two factors may be related to the activity and severity of the disease.The mechanism of Tfh cells potentially leading to an increase of Gd-IgA 1 production requires further study.
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OBJECTIVE@#To study the clinical features of vesicoureteral reflux (VUR) in children with neurogenic bladder (NB), and to provide a reference for its early diagnosis and treatment.@*METHODS@#Clinical data were collected from 26 children with NB and urinary tract infection who were admitted to the Department of Pediatric Nephrology from January 2014 to December 2019. According to the presence or absence of VUR, the children were divided into a VUR group with 11 children and a non-VUR group with 15 children. Clinical features were compared between the two groups.@*RESULTS@#Compared with the non-VUR group, the VUR group had a significantly higher proportion of children with non-@*CONCLUSIONS@#When NB children have the clinical manifestations of non-
Subject(s)
Child , Humans , Infant , Creatinine , Radionuclide Imaging , Urinary Bladder, Neurogenic/etiology , Urinary Tract Infections/etiology , Vesico-Ureteral Reflux/diagnostic imagingABSTRACT
Objective:To help clinicians simplify the post-processing operations of structures by developing rapid processing software for target area and organs at risk structures based on ESAPI.Methods:SmartStructure script software was developed based on ESAPI, verified and evaluated in clinical work. 10 cases of rectal cancer receiving neoadjuvant radiotherapy, 10 breast cancer treated with postoperative radiotherapy, 10 cervical cancer receiving postoperative radiotherapy, 10 nasopharyngeal carcinoma receiving radical radiotherapy and 10 lung stereotactic body radiotherapy (SBRT) were selected, and different types of tumors had different post-processing operations of structures. In each case, three methods were used for post-processing of structures. In the control group (manual group), normal manual processing was employed. In the experimental group 1(SmaStru-N group), scripts without templates were utilized. In the experimental group 2(SmaStru-P group). scripts combined with templates were adopted. The processing time of the three methods was compared. Clinicians scored the scripting software from multiple aspects and compared the feeling scores of scripting software and manual operation.Results:All three methods can be normally applied in clinical settings. The error rate in the manual group was 7.0%, 3.0% in the SmaStru-N group 0% in the SmaStru-P group, respectively. Compared with the manual method, SmaStru-N shortened the processing time of target area and organs at risk by 60.9% and 93.3% for SmaStru-P. In addition, SmartStructure was superior to manual method in terms of using feeling scores. Clinicians gave lower score for the" applicability" and" simplicity" , and higher score on the" accuracy" and" efficiency" .Conclusions:Compared with conventional manual structure processing method, SmartStructure software can rapidly and accurately process all structures of the target area and organs at risk, and its advantages become more obvious with the increasing number of structures that need to be processed. SmartStructure software can meet clinical requirements, reduce the error rate, elevate processing speed, improve the working efficiency of clinicians, providing basis for the development of adaptive radiotherapy.
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Radiation therapy plays an important role in the adjuvant treatment of patients with early endometrial carcinoma. Vaginal stump is a common site of disease failure for early endometrial carcinoma patients with intermediate-high risk factors for recurrence. Compared with external beam radiotherapy, vaginal brachytherapy (VBT) can achieve comparable local control rate with fewer toxicities. In this article, research progresses upon the application of VBT in patients with early endometrial carcinoma after hysterectomy were investigated from multiple perspectives of the selection of patients, the selection of vaginal applicator, factors influencing dose distribution, image-guided adaptive brachytherapy, the design and implementation of radiotherapy regime. In addition, the application of intensity-modulated VBT and the usage of novel quality assurance equipment were also discussed.
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Objective:To compare the dosimetric parameters and plan complexity between newly-delicated HyperArc (HA) and conventional volumetric-modulated arc therapy (VMAT) in the treatment of brain metastases.Methods:For 26 patients with brain metastases, HA, conventional coplanar (Cop) and non-coplanar (Non-cop) VMAT plans with a prescription dose of 9 Gy 3fx or 6 Gy 5fx were generated. The dosimetric parameters for planning target volume (PTV), RTOG conformity index (RTOG CI), Paddick CI, homogeneity index (HI), gradient index (GI), maximum dose (D max) of brainstem and dose-volume parameters of brain-PTV(V 2Gy-V 26Gy) were statisticaly compared among these three approaches. In addition, the monitor unit (MU) and the plan complexity parameters (including MCSv and AlPO) were statistically compared. Results:To prevent missed targets during treatment, all plans were established with RTOG CI of greater than 1.1. For Paddick CI, HA provided significantly higher conformity (0.89±0.019) than Non-cop (0.87±0.036, P=0.001) and Cop (0.88±0.017, P=0.003) VMAT. For GI, the fastest dose fall-off was noted in HA (3.35±0.64), followed by conventional Non-cop VMAT of (3.70±0.80), and conventional Cop VMAT of (4.90±1.85)(all P<0.05). For the brainstem sparing, HA plan performed better than Non-cop plan[(604.14±531.61) cGy vs.(682.75±558.22) cGy, P<0.05)]. For normal brain tissue sparing, HA approach showed significant reduction than conventional Cop and Non-cop VMAT (both P<0.05). For MU, HA approach (2 872.60 ± 566.93) was significantly lower than those of Non-cop VMAT (3 771.28 ± 1 022.38, P<0.05) and Cop VMAT (4 494.08 ± 1 323.09, P<0.05). In terms of plan complexity, the MCSv of Cop plan was the lowest, indicating that the complexity was the highest ( P<0.05). The AlPO of HA was significantly higher than that of Non-cop VMAT ( P<0.05), suggesting that the complexity of HA plan was lower ( P<0.05). Conclusion:For the treatment of brain metastases, HA provides better conformity, more rapid dose fall-off, better sparing of brainstem and normal brain tissues and less plan complexity compared with conventional VMAT.
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Objective:To study the feasibility of using pelvic iterative cone beam CT images for dose calculation of radiation therapy planning, so as to provide support for adaptive radiotherapy.Methods:The CIRS 062 M phantom was scanned by Varian Halcyon v2.0 o-ring accelerator, and the average CT number under different scattering conditions was calculated, and then the ICBCT-ED conversion curve was established. CT images of CIRS 002PRA pelvic IMRT phantom and ICBCT images at different positions were collected. Treatment plan using VMAT technique based on CT image was designed and transplanted into ICBCT image with dose recalculated. The differences of gamma passing rate among target volume, organs at risk and 3-dimensional dose were compared. Based on the actual treatment plan of patients, the differences of 3-dimensional dose gamma passing rate in 10 pelvic patients were analyzed retrospectively.Results:There was a large CT value deviation at central position between the isolated no-scattering condition and the full-scattering condition, and the maximum deviation was 144 HU. The CT values of other positions in full-scattering condition were similar to those of the central position, and the maximum deviation was less than 50 HU. Based on the calculated result of ICBCT images at different positions of the pelvic phantom, the dose deviation of the target volume or organs at risk was less than 1 Gy. Compared with the plan based on CT images, the average 3-dimensional dose gamma passing rate under the criteria of 1% dose difference (DD)/1 mm distance-to-agreement (DTA) and 2% DD/2 mm DTA in plan based on ICBCT images were (88.86 ±1.18)% and (98.38±0.89)%, respectively. The ranges of average 3-dimensional dose gamma passing rate under the criteria of 2% DD/2 mm DTA and 3% DD/3 mm DTA in 10 patients with pelvic tumors were 90.03%-95.43% and 93.58%-97.78%, respectively, and the worst result was only 85.90% and 92.90%, respectively. The main reason of the worst result was the dose difference caused by large variation of bladder contour due to over-filling.Conclusions:Under comprehensive scattering conditions, the ICBCT-ED conversion curve is reconstructed and the treatment plan can be designed by using the ICBCT image of Halcyon v2.0 linear accelerator. The accuracy meets the standards of clinical application, which provides assurance for adaptive radiotherapy in the future.
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Objective:To compare the calculation result and analyzes the reasons for their differences so as to provide reference for the revision and improvement of the current national standards on radiation shielding design for the room of brachytherapy.Methods:For the initial activity 10 Ci (1 Ci=3.7×10 10 Bq) of radioactive sources, the shielding schemes of brachytherapy room were designed in accordance with UK Institnte of Physics and Engineering in Medicine(IPEM) Report 75, USA NCRP Report 151 and the national standard GBZ/T 201.3-2014, respectively. The differences in shielding limits, occupancy factors and other relevant factors are compared in detail. Results:The annual exposure time in a typical brachytherpy room was about 330 h. The point-specific concrete thickness were 70, 65, 61, 70, 50 cm as required by NCRP Report 151, 41, 43, 30, 40, 39 cm by IREM regulations and 84, 79, 46, 88, 39 cm by GBZ/T 201.3, respectively. The concerned concrete shielding thickness calculated under the GBZ/T 201.3-2014 was generally thicker, with lesser difference from NCRP Report 151 result, whereas that from the IPEM75 report was thinnest. The equivalent lead shielding thicknesses of the protective doors calculated using the three method are 1.170, 0.854 and 1.040 cm, respectively.Conclusions:The shielding thickness calculated using the calculation method and evaluation index recommended by the current Chinese shielding standards for brachytherapy bunker is similar to that reported in NCRP151, but is conservative. In particular, the evaluation index of instantaneous dose equivalent rate required by the current national standards and the relative conservative value of occupancy factor will significantly increase the shielding thickness required by the main shielding area.
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Objective:To discuss the design details of accelerator room for a novel enclosed O-ring linac Halcyon, and to optimize its protection and layout.Methods:According to the optimization principle of radiation protection and the requirements of national radiation protection standards, and the structural characteristics of Halcyon accelerator, the differences between conventional and this novel accelerator rooms were analyzed by discussing the space layout of the machine room, shielding calculation, electrical facilities, purifying ventilation, temperature and humidity control and other factors.Results:The Halcyon machine had a compact structure, a closed ring frame design and a main beam shielding device, which could greatly reduce the radiation protection pressure while improving the space utilization rate of the machine room. The optimized design layout of the machine room could eliminate hidden dangers, avoid design defects, and prevent adverse consequences caused by design errors.Conclusions:The overall structure of Halcyon accelerator is different from that of conventional accelerators. The design details should be taken into full consideration to ensure the optimization of radiation protection, lay a good foundation for subsequent installation, debugging and operation of the equipment and create a good treatment environment for patients and medical staff.
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OBJECTIVE@#To detect the relationship between CTGF in the bone marrow of MM patients and osteolytic lesion of myeloma, moreover, to investigate the clinical significance of CTGF in MM.@*METHODS@#Fifity-four MM patients treated in our hospital from March 2019 to April 2020 were enrolled, and 28 healthy volunteers were selected as the control group. The plasma in bone marrow of the patients was collected, and the ELISA was used to detect the level of CTGF in bone marrow plasma and the relationship between its and clinical characteristics were statistically analyzed.@*RESULTS@#The CTGF level of MM patients was significantly higher than those in the healthy control group (P<0.001); the CTGF level in male patients was higher than that in female patients (P=0.007); the CTGF level in MM patients with osteolytic lesions was significantly higher than patients without osteolytic lesions and controls (P=0.007, P=0.001). The CTGF level in MM patients was positively correlated with the number of bone lesions (P<0.001, r=0.52). CTGF levels in patients with ≥3 bone lesions were significantly higher than those with <3 bone lesions and without bone lesions (P=0.014, P=0.002). ROC curve result showed that CTGF expression level shows a significant diagnostic value for MM bone disease (P<0.001).@*CONCLUSION@#The abnormally high expression of CTGF level in MM patients is related to the degree of myelomas osteolytic lesions and can reflect the progress of MM.
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Female , Humans , Male , Bone Marrow , Connective Tissue Growth Factor , Multiple Myeloma , Osteolysis , Patients , ROC CurveABSTRACT
OBJECTIVE@#To study the long-term prognosis of vesicoureteral reflux in children.@*METHODS@#A retrospective analysis was performed for the clinical data of 138 children (218 ureters with reflux) who were diagnosed with vesicoureteral reflux for the first time from November 2005 to March 2017 and received medical treatment and regular follow-up. According to the initial grade of reflux, the ureters with reflux were divided into a low-grade group (141 ureters, grade I-III) and a high-grade group (77 ureters, grade IV-V), and the two groups were compared in terms of clinical data and follow-up results.@*RESULTS@#Among the 138 children, there were 82 boys and 56 girls. Their age ranged from 31 days to 10 years at the time of confirmed diagnosis, with a median age of 8 months. The follow-up time ranged from 8 months to 7 years, with a median follow-up time of 1.4 years. At the time of confirmed diagnosis, the high-grade group had significantly higher levels of urinary N-acetyl-β-D-glucosaminidase, urinary microalbumin and urinary immunoglobulin G than the low-grade group (P<0.05). Among the 218 ureters with reflux, 132 (60.6%) achieved a reduction in the grade of reflux (among which 74 achieved complete disappearance of reflux), 43 had no change in the grade of reflux, and 43 had an increase in the grade of reflux. Compared with the high-grade group, the low-grade group had a significantly higher complete remission rate (41.1% vs 19.5%, P=0.001) and a significantly shorter time to complete remission of reflux (P=0.002).@*CONCLUSIONS@#Most children with vesicoureteral reflux can achieve a reduction in the grade of reflux or even complete disappearance of reflux during follow-up, and the children with low-grade reflux have better prognosis than those with high-grade reflux.
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Child , Child, Preschool , Female , Humans , Infant , Male , Follow-Up Studies , Prognosis , Retrospective Studies , Vesico-Ureteral RefluxABSTRACT
Objective To analyze the failure and processing methods of helical tomotherapy multileaf collimator (MLC) and summarize relevant maintenance experience,aiming to accurately identify the faulty parts,shorten the downtime and enhance the work time.Methods The failure data of the helical tomotherapy MLC system in the past 48 months were analyzed to identify the common faulty parts,causes and processing methods.Results During the previous 48 months,the MLC failure occurred for 20 times,11 times for air compressor failure,4 times for position verification board failure,twice for leaf driver failure,twice for cushion valve failure and once for the slip of leaf position verification rod.The MLC failure was significantly correlated with the humidity of high-pressure gas.The work time of machine exerted significant effect upon the service time of MLC parts.Conclusions The structure of the helical tomotherapy MLC system is complex.The high-intensity work increases the failure rate.The humidity of high-pressure gas affects the normal operation of the MLC equipment.The faulty parts can be identified,the downtime can be reduced and the work time can be enhanced by summarizing the experience of MLC maintenance.