Objective To explore the expression, correlation with clinicopathologic parameters, and clinical significance of MIS18 binding protein 1 (MIS18BP1) in bladder cancer. Methods TCGA and GEO databases were used to analyze the mRNA expression of MIS18BP1 in tumors and controls, and the results were verified via qRT-PCR. UALCAN online database was utilized in the analysis of the expression of MIS18BP1 and its correlation with clinicopathological parameters and the degree of immune cell infiltration. Immunohistochemistry was employed to analyze the expression of MIS18BP1 in bladder cancer and its relationship with clinicopathological features. The ROC curve was applied to evaluate the diagnostic value of MIS18BP1 mRNA in bladder cancer. Results Bioinformatics analysis and qRT-PCR results revealed the increased expression of MIS18BP1 mRNA in bladder cancer compared with that in the control group (P<0.05). Immunohistochemistry unveiled the significantly high positive rate of MIS18BP1 protein in bladder cancer (P<0.05) and its correlation with the clinical stage of tumors, depth of invasion, and lymph node metastasis (P<0.05). The immune infiltration analysis showed the association of MIS18BP1 with immune cell infiltration in bladder cancer. Conclusion The increased expression level of MIS18BP1 gene and protein in bladder cancer may regulate the development of bladder cancer by influencing immune cell infiltration.

Objective To present and discuss beam characteristics of the first Mevion S250i gantry-mounted accelerator pencil beam scanning proton therapy system in China.Methods The output dose was measured using a parallel-plate ionization chamber.The integrated depth dose was measured with a large-radius Bragg peak ionization chamber,covering 19 energy levels ranging from 227 MeV to 28 MeV,to analyze the proton beam characteristics.The spots in the air were measured with Phoenix flat panel detector on the beam central axis,and the precision of the delivery position was verified by measuring the multi-spot beam map.The interleaf leakage and penumbra reduction of adaptive aperture were measured to characterize its performance.Results The proton system was calibrated for a maximum energy of 227 MeV,with a(10×10)cm2uniform field delivering 1 Gy dose at a depth of 5 cm underwater.The system effectively modulated the proton beam range to the patient's surface,maintaining a constant 80%-80%Bragg peak width of 8.6 mm at all energy levels.The spot size of the highest energy beam at the isocenter was about 4 mm in the air,and the spot delivery position error was less than 1 mm.The interleaf leakage rate of the adaptive aperture for the highest energy beam was below 1.5%,and the penumbra was significantly reduced.Conclusion Mevion S250i proton therapy system demonstrates unique design and beam characteristics,which is reflected in the Bragg peak shape,spot size variation with energy,and penumbra sharpening of adaptive aperture;and these differences should be considered in treatment planning system modeling and planning for precision treatment.

Objective:To evaluate the clinical application value of the adaptive aperture by comparing intensity-modulated proton radiotherapy(IMPT) plans using and not using the aperture for brain tumors.Methods:A total of twenty patients treated with postoperative radiotherapy for brain tumors were enrolled in this study. IMPT plans were developed for each patient using and not using the adaptive aperture under the same optimization conditions. The target conformal index (CI) value, target homogeneity index (HI) value, and the dose to normal tissues of the two sets of plans were compared.Results:The IMPT plans designed using the adaptive aperture significantly increased the mean CI value from 0.58 to 0.66, while decreasing the mean 50% prescription dose volume from 797.70 cm 3 to 638.15 cm 3. These plans also reduced the irradiation doses to the cochlea, brainstem, optic chiasm, optic nerve, and lens ( t = 2.06, 3.02, 2.11, 2.58, 2.67, P < 0.05). Additionally, there was no significant difference in the HI value of the target volumes and the machine jumps (MU) between the two sets of plans ( P > 0.05). Conclusions:The adaptive aperture can significantly reduce the irradiation dose to normal tissues outside the target volumes, positively impacting the protection of organs at risk (OARs) around the target values. This demonstrates its great potential for clinical application.

Objective:To analyze the prevalence and related factors of depression symptom among middle-aged and older adults belonging to Zhiguo ethnic minority groups,who experienced relative isolation prior to mod-emization and bypassed the transitional period associated with feudal monarchy in Yunnan Province.Methods:Using stratified cluster sampling,a total of 1 035 individuals from Zhiguo ethnic minority groups were investigated with the 9-item Patient Health Questionnaire(PHQ-9)to measure depression symptom scores(a total score≥5 was considered indicative of depression symptom).A self-administered questionnaire was utilized to investigate 24 cova-riates across five dimensions:sociodemographic,social-interpersonal network,mental health status,physical health status,and health behaviors.Results:Among the surveyed participants,231 individuals(22.32％)exhibited depres-sion symptoms.The logistic regression analysis showed that middle-aged and elderly people belonging to Zhiguo ethnic minority groups with occupations as laborers(OR=8.73),farmers(OR=7.34),and other professions(OR=7.13),those who reported feeling stressed or anxious in the last month(OR=5.43),those suffering from one(OR=2.81)or more chronic illnesses(OR=2.14),experiencing sleep problems(OR=3.74)/debilitating(OR=1.69)/mild-moderate pain(OR=2.23,4.37),and engaging in sedentary behavior(OR=2.27)were at higher risk for depressive symptoms.The risk of depressive symptoms was lower among middle-aged and elderly people be-longing to Zhiguo ethnic minority groups with higher social support scores(OR=0.96)and meaning in life scores(OR=0.96).Conclusion:The prevalence of depressive symptoms among middle-aged and elderly individuals of Zhiguo ethnic minorities is substantial,influenced by multiple factors.

Objective To analyze the daily quality assurance(QA)measurement results of IBA Sphinx Compact device on the Mevion compact pencil beam scanning proton therapy system for evaluating its clinical application value in proton therapy.Methods The daily QA measurement of Mevion S250i proton therapy system was carried out with Sphinx Compact device for 30 consecutive days,and the measurement results were analyzed.Results The average deviation between the positioning laser and the image center was(0.42±0.27)mm in 30 days.All of the proximal and distal depth errors of the high-and low-energy pencil beams were within 0.50 mm.The position deviation of all the spots measured did not exceed 1.00 mm,and the size deviation was less than 7.5%.The deviation between the image center and the beam center was not more than 0.75 mm.The relative deviation of the flatness of the rectangular field was about 0.5%.The deviation of the output dose of the square field was within 1.0%.Conclusion The proton system daily QA measurement items recommended by AAPM TG-224 report can be accurately and rapidly measured with Sphinx Compact device.The device is a practical and efficient daily QA tool with high practical value in clinic.

Objective:To discuss the acceptance test of beam performance and mechanical precision of the first Mevion type S250i proton therapy system in China,and verify the stability and reliability of that in clinical treatment.Methods:According to the requirements of acceptance report of manufacturer,the output and range of machine unit(MU),the accuracy and stability of size and position of beam spot,the penumbra and position accuracy of adaptive aperture(AA)of Mevion type S250i proton therapy system,as well as the tests of mechanical properties and functions of the requirement of clinical use,were checked and tested for acceptance.Results:The maximum deviation of MU output was 1.3%,and the maximum deviation of the range was 0.037 g/cm2,and the maximum distal fall-off was 0.465 cm,and the minimum range of energy modulation was 0.21 g/cm2.The maximum deviations of the size of beam spot and the maximum deviation of the position were respectively 0.07 cm and 0.05 cm.The maximum AA penumbra was 0.007 cm,and the AA position accuracy was less than 0.1 cm.Conclusion:The acceptance test of the Mevion type S250i proton therapy system indicates that the parameters of the beam performance and mechanical precision can meet the requirements of the acceptance contract and AAPM-TG224 report of manufacturer,which has verified the machine has better favorable stability and reliability.

Objective:To measure and assess relevant radiation doses at the radiotherapy site of the first domestic single-vault proton therapy system.Methods:The radiation levels of the therapy system during and after beam irradiation were measured, and annual effective doses were assessed for personnel at the site.Results:During beam irradiation, the highest radiation dose was detected at the shielded door of the equipment floor, with a gamma radiation level of 2.140 μSv/h and a neutron radiation level of 0.850 μSv/h. Neutron radiation disappeared immediately once the beams stopped. In contrast, the radiation activated originated mostly from gamma rays. A longer time after beams stopped was associated with lower induced radiation intensity at the same location. Furthermore, a farther distance from the irradiated object corresponded to lower induced radiation intensity at the same time. The assessment result reveal that the annual effective doses to the personnel were at the safe level, with physicists exposed to the highest dose of 2.138 mSv.Conclusions:The radiation level at the studied proton therapy site meets the safety requirement, and the treatment can be performed safely at this site.

Objective:To verify and calibrate the CT modeling curves of three CT devices in RayStation proton treatment planning system (TPS).Methods:CT-mass density (CT-MD) curves were established by CT Hounsfield units of different tissue substitute materials obtained by scanning the model with CT equipment. CT-stopping power (CT-SP) curves were established by calculation based on the chemical composition of various human tissues. The equivalent water thickness of tissue substitute modules was calculated with different CT modeling curves in TPS. The actual equivalent water thickness of various modules was measured by a Bragg peak detector, and compared with the calculated values of TPS to verify the accuracy of different CT models.Results:The differences of CT modeling curves were significantly different under different tube voltage scanning protocols. Compared with CT-MD curves, CT-SP curves based on the stoichiometric calibration were more suitable for proton dose calculation. However, the values of stopping power corresponding to high CT values still needed to be optimized, and the calculation error after calibration was less than 3%.Conclusion:The method of verifying and calibrating CT unit curves of proton TPS is described, proving that the CT-SP curves after stoichiometric calculation are more suitable for proton dose calculation.

The acute combination fractures of the atlas and axis in adults have a higher rate of neurological injury and early death compared with atlas or axial fractures alone. Currently, the diagnosis and treatment choices of acute combination fractures of the atlas and axis in adults are controversial because of the lack of standards for implementation. Non-operative treatments have a high incidence of bone nonunion and complications, while surgeries may easily lead to the injury of the vertebral artery, spinal cord and nerve root. At present, there are no evidence-based Chinese guidelines for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults. To provide orthopedic surgeons with the most up-to-date and effective information in treating acute combination fractures of the atlas and axis in adults, the Spinal Trauma Group of Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field of spinal trauma to develop the Evidence-based guideline for clinical diagnosis and treatment of acute combination fractures of the atlas and axis in adults ( version 2023) by referring to the "Management of acute combination fractures of the atlas and axis in adults" published by American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) in 2013 and the relevant Chinese and English literatures. Ten recommendations were made concerning the radiological diagnosis, stability judgment, treatment rules, treatment options and complications based on medical evidence, aiming to provide a reference for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults.

Objective:To investigate the feasibility of dynamic contrast-enhanced (DCE)-MRI in assessing the depth of invasion (DOI) of early tongue squamous cell carcinoma.Methods:From January 2016 to December 2020, a total of 100 patients with early tongue squamous cell carcinoma confirmed by postoperative pathology were retrospectively analyzed in the Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine. The study included 48 cases of T1 stage and 52 cases of T2 stage. All patients underwent routine MRI, DCE-MRI and contrast-enhanced T 1WI (CE-T 1WI) before surgery. The DOI was measured on images at different phases of axial DCE-MRI (30, 60 and 120 s after contrast injection) and CE-T 1WI (MRI-DOI) by 2 doctors independently. The intraclass correlation coefficient (ICC) was applied to evaluate the consistency of the measurements. MRI-DOI measured on DCE-MRI 30, 60, 120 s, CE-T 1WI and pathological DOI measured on biopsies were statistically analyzed with analysis of variance for repeated measurement and least significant difference t test. Pearson correlation coefficient was used to compare the correlation between MRI-DOI and pathological DOI. Receiver operation characteristic (ROC) curve analysis was used to explore the performance of MRI-DOI for clinical T1 and T2 staging. Results:There was a good consistency in MRI-DOI measured on DCE-MRI 30, 60, 120 s, and CE-T 1WI images with ICC of 0.752, 0.875, 0.883, and 0.841, respectively. The values of MRI-DOI were (8.35±3.52), (6.88±2.41), (7.52±2.65) and (8.60±3.39) mm, respectively, and pathological DOI was (5.75±2.01) mm. There was statistically significant difference in the overall comparison among different phases of MRI-DOI and pathological DOI ( F=69.25, P<0.001). MRI-DOI were significantly higher than pathological DOI ( P<0.05). All MRI-DOI measured on DCE-MRI 30, 60, 120 s and CE-T 1WI correlated positively with pathological DOI ( r=0.574, 0.851, 0.731, 0.663, all P<0.001). MRI-DOI derived from DCE-MRI 60 s showed the highest diagnostic efficiency for T1 and T2 staging (area under the ROC curve was 0.931, 95%CI 0.881-0.982). When the optimal cutoff value was 6.0 mm, the accuracy, sensitivity and specificity were 88.0%, 96.2% and 79.2%, respectively. Conclusions:DCE-MRI can be applied to assess DOI in early tongue squamous cell carcinoma. MRI-DOI based on DCE-MRI 60 s has the best correlation with pathological DOI and has a potential to predict clinical T staging in early tongue squamous cell carcinoma.