At present, the C-arm structure accelerators commonly used in radiotherapy equipment are complex in operation and have potential safety hazards when realizing non-coplanar treatment. By combining with medical robotic arm technology, a spherical radiotherapy accelerator motion system is designed. The beam module is clamped by the medical robotic arm structure to achieve three-dimensional multi-angle irradiation treatment within the non-coplanar angle range. Firstly, the rotating mechanism, beam module, and MLC module of the spherical radiotherapy equipment are designed. Then, the double-plane counterweight method is used to calculate the dynamic balance of the equipment, ensuring that the beam center point does not rotate during the treatment process. Finally, the strength check and reliability analysis of the transmission component gear are conducted. The results show that the designed spherical radiotherapy accelerator motion system can meet the requirements of stable, accurate, and fast precision radiotherapy, which is conducive to improving the treatment efficiency.
Particle Accelerators/instrumentation* ; Equipment Design ; Reproducibility of Results ; Radiotherapy/instrumentation*

Clopidogrel effectively inhibits platelet aggregation in response to ADP by irreversibly binding to the platelet P2Y₁₂ receptor through its active metabolite. However, the observed discrepancies between the pharmacokinetics (PK) and pharmacodynamics (PD) of clopidogrel present substantial challenges in individualizing of antiplatelet therapy. To address these challenges, a robust liquid chromatography-tandem mass spectrometry method has been developed to facilitate the real-time assessment of platelet P2Y₁₂ receptor occupancy. This method has been validated in animal models, providing a reliable link between individual PK profiles and PD effects. Target receptor occupancy offers a comprehensive overview of interindividual variations in clopidogrel metabolism, regulation of P2Y₁₂ receptor expression, and platelet turnover. Moreover, it directly correlates with the inhibitory effect on platelet aggregation. The levels of platelet P2Y₁₂ occupancy accurately reflect the extent of clinical factors influencing the PD of clopidogrel, including dosage, drug-drug interactions (DDI), and type 2 diabetes mellitus (T2DM). As a normalized metric, platelet P2Y₁₂ occupancy not only serves potential as a diagnostic tool for personalized clopidogrel therapy but also aids in elucidating the role of the P2Y₁₂ signaling pathway in cases of abnormal on-treatment platelet reactivity.

Objective:To investigate the clinical and pathological characteristics and prognosis of children with lupus nephritis(LN)and thrombotic microangiopathy (TMA).Methods:In this retrospective case-control study, clinical and pathological data of LN children confirmed by renal biopsy from January 2008 to January 2023 in Xuzhou Children′s Hospital, Xuzhou Medical University were analyzed.There were 46 LN children complicated with TMA (LN-TMA group). With matched age, sex and pathology, 92 LN children (1∶2) without TMA were selected as the control group (LN group). The Kaplan-Meier method was used to evaluate the overall and renal survival rates of children with LN, and the Cox regression model was used to analyze the risk factors for the progression to end-stage renal disease (ESRD).Results:TMA was moderately associated with serum creatinine, serum C3, anti-C1q antibody (a-C1q), estimated glomerular filtration rate (eGFR), endocapillary proliferation, fibrinoid necrosis, and renal C1q deposition (all r>0.5). Serum a-C1q≥20 U/mL ( HR=8.724, 95% CI: 0.976-16.114, P=0.026) and eGFR≤60 mL/(min·1.73 m 2) ( HR=12.213, 95% CI: 1.147-25.048, P=0.038) were independent risk factors for TMA in children with LN.Glomerular sclerosis ( HR=7.228, 95% CI: 0.186-22.358, P=0.016), TMA ( HR=11.387, 95% CI: 3.426-42.554, P=0.009) and eGFR≤60 mL/(min·1.73 m 2) ( HR=3.116, 95% CI: 0.592-10.064, P=0.030) were independent risk factors for developing ESRD in LN children.The 5-year and 10-year renal survival rates in the LN-TMA group were lower than those in the LN group (97.44% vs.98.28%, 80.90% vs.87.27%, χ2=4.918, P=0.027). Conclusions:Children with LN-TMA present with severe symptoms and poor prognosis.TMA is an independent risk factor for progression to ESRD in children with LN, and the mechanism may be related to complement activation.

Objective To investigate the significance of intratumoral and peritumoral radiomics models in predicting occult lymph node metastasis in stage T1 non-small cell lung cancer(NSCLC)and to compare the predictive accuracy in different peritumoral radiomics models.Methods The CT images and clinical data of 211 patients without lymph node metastasis on preoperative CT examination and pathologically confirmed NSCLC after surgery were collected.The radiomics features were derived from the three-dimensional volume of interest(VOI)of the intratumoral and peritumoral at 3-,5-,and 10-mm following lesion segmentation on CT images of each patient.The feature data of all nidus were radomly divide into training set and validation set with a ratio of 7︰3.The Pearson or Spearman correlation test was performed to remove redundancy.Dimensionality was reduced by the least absolute shrinkage and selection operator(LASSO)regression analysis.The linear combination of selected features and corresponding coefficients were used to construct the Radiomics score(Radscore).The clinical model and comprehensive model were constructed by logistic regression analysis.The conprehensive model was visualized with the nomogram,and its performance was evaluated.Results Among the peritumoral radiomics models,the peritumoral 5-mm model showed the best predictive efficacy[validation set,area under the curve(AUC)0.771].The comprehensive model containing Radscore,CT image features and CEA exhibited the best performance(validation set,AUC 0.850).Conclusion Intratumoral and peritumoral radiomics models perform efficiently in predicting occult lymph node metastasis in stage T1 NSCLC,and nomogram can effectively and noninvasively predict occult lymph node metastasis in NSCLC.

Objective:To investigate the effect of the ratio of the maximum diameter of aneurysm sac to age (R) on the long-term efficacy of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in patients with infrarenal abdominal aortic aneurysm (IAAA).Methods:This is a retrospective cohort study.The clinical data of 317 patients with IAAA who underwent surgical repair in the Department of Vascular Surgery,the Third Affiliated Hospital of Sun Yat-Sen University from January 2016 to October 2022 were retrospectively collected.There were 266 males and 51 females,aged (69.7±8.3) years (range:37 to 87 years).The R value of the patient was calculated and the receiver operating characteristic(ROC) curve was used to establish a model to calculate the optimal cut-off value.The propensity score matching method was used to match the baseline data of patients in the EVAR and OSR group by 3∶1 (the caliper value was 0.05),and the patients were stratified according to the cutoff value of R, and the postoperative efficacy and survival of the patients were analyzed.The primary endpoint was the total mortality rate,and the secondary endpoints included the occurrence of postoperative complications and reintervention.Pearson χ2 or Fisher ′s exact test was used for categorical variables, and independent sample t test or Wilcoxon rank sum test was used for continuous variables to compare differences between groups.The survival curves of the two groups were described by Kaplan-Meier method. Results:After propensity score matching,198 cases were in the EVAR group and 66 cases were in the OSR group.The ROC model showed that the best cut-off value of R value was 0.90,and the two groups were divided into two layers:R<0.90 and R≥0.90.Among them,112 patients with R<0.90 (84 cases of EVAR,28 cases of OSR);there were 152 patients with R≥0.90 (114 cases of EVAR and 38 cases of OSR).The follow-up time was (23.6±1.6) months (range:1 to 70 months).In the R≥0.90 stratification,the total mortality (26.3% vs.5.3%, χ2=7.600， P=0.006),complication rate (44.7% vs.26.3%, χ2=4.025， P=0.045), and secondary intervention rate (31.6% vs.13.2%, χ2=4.910， P=0.027) in the EVAR group were higher than those in the OSR group.In the R<0.90 stratification,there was no significant difference in the total mortality rate (13.1% vs.10.7%, χ2=0.109， P=0.741), complication rate (28.6% vs.35.7%, χ2=0.507， P=0.477) and secondary intervention rate (14.3% vs.21.4%, χ2=0.353， P=0.552) between the two groups. Conclusions:When R≥0.90 in IAAA patients,OSR maybe more beneficial to patients in terms of survival rate,postoperative complication rate and secondary intervention rate than EVAR.When R<0.90,there are no significant differences in survival rate,complication rate and secondary intervention rate between the two surgical methods.

Objective: To investigate the current status and relationship between loneliness and negative emotional symptoms among first generation college students in the family, so as to provide reference for improving mental health of this population. Methods: A convenience sampling method was used to select 3 017 college students from 10 colleges and universities in Guangdong Province and Yunnan Province, China, in May 2023. Questionnaires were administered to the students, and the Depression Anxiety Stress Scale (DASS-21) and the short form of the University of California at Los Angeles Loneliness Scale (ULS-6) were employed. Results: The total ULS-6 score of first generation college students in the family was (12.38±4.16), while the score of non first generation college students in the family was (11.89±4.38), with a statistically significant difference ( t=2.79, P <0.05). The total DASS-21 score of first generation college students in the family was (71.13±26.97), while the score of non first generation college students in the family was (70.20±26.66), with a statistically significant difference ( t=2.69, P <0.05). Among the first generation college students in the family, male students experienced more DASS-21 score (77.55±29.36) than female students (70.43±25.03)( t =5.79, P <0.05). Urban students (12.00±4.15, 70.34±25.68) reported lower levels of loneliness score and DASS- 21 score than rural students (12.62±4.15, 74.93±27.63), and the depression subscale scores showed statistically significant differences among students with different professional achievement rankings ( t/F =-3.42, -3.94, 4.25, P <0.05). There was a positive correlation between loneliness, depression, anxiety, pressure and DASS-21 scales of first generation college students in the family ( r=0.64, 0.62, 0.64, 0.66, P <0.01). The linear regression analysis results showed a positive correlation between loneliness and all dimensions and total scores of the DASS-21, explaining 44% of the variance in negative emotional symptoms. Conclusions A positive correlation is found between loneliness and negative emotional symptoms among first generation college students in the family. Improving the loneliness of the first generation college students in the family can reduce their negative emotional symptoms and improve their mental health level.

Objective To understand the epidemiological characteristics of scrub typhus disease and to provide a scientific basis for the prevention and control of scrub typhus disease. Methods Descriptive epidemiological methods were used to analyze the population and regional distribution of scrub typhus. Seasonal characteristics were analyzed using concentration method and circular distribution method, and incidence trend was analyzed using joinpoint regression model. Results The annual incidence rate of scrub typhus was 0.95/100 000 from 2010 to 2022. The incidence rate of male was 0.77/100 000, lower than that of female 1.12/100 000 (χ²=18.89, P<0.05). The incidence rate of the 60-74 years old group was 3.38/100,000, and the total number of cases in the age group 45-74 years was 416 (74.95%). Occupational distribution was mainly among farmers, with 448 cases (80.72%). The top three regions with the highest number of reported cases (in order: Donghai County, Ganyu District, and Guannan County) reported a total of 416 cases, accounting for 74.95%. Concentration ratio was M=0.9408, and the incidence of scrub typhus disease was strictly seasonal. Circular distribution results showed a^-=-62.3728, S=20.8960. The circular distribution results indicated that the peak day was October 19th, and the peak period was between October 7 to December 19. The average annual percentage change (AAPC) of the incidence rate from 2010 to 2022 was 13.70%, 95% CI (-8.62%~41.48%), and the incidence rate showed an upward trend (t=1.15, P=0.249). Conclusion The incidence of scrub typhus disease is strictly seasonal, and the incidence rate over the years shows an upward trend. It is necessary to strengthen monitoring and take various intervention measures to reduce the risk of scrub typhus disease.

Objective:To investigate the effect of the ratio of the maximum diameter of aneurysm sac to age (R) on the long-term efficacy of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in patients with infrarenal abdominal aortic aneurysm (IAAA).Methods:This is a retrospective cohort study.The clinical data of 317 patients with IAAA who underwent surgical repair in the Department of Vascular Surgery,the Third Affiliated Hospital of Sun Yat-Sen University from January 2016 to October 2022 were retrospectively collected.There were 266 males and 51 females,aged (69.7±8.3) years (range:37 to 87 years).The R value of the patient was calculated and the receiver operating characteristic(ROC) curve was used to establish a model to calculate the optimal cut-off value.The propensity score matching method was used to match the baseline data of patients in the EVAR and OSR group by 3∶1 (the caliper value was 0.05),and the patients were stratified according to the cutoff value of R, and the postoperative efficacy and survival of the patients were analyzed.The primary endpoint was the total mortality rate,and the secondary endpoints included the occurrence of postoperative complications and reintervention.Pearson χ2 or Fisher ′s exact test was used for categorical variables, and independent sample t test or Wilcoxon rank sum test was used for continuous variables to compare differences between groups.The survival curves of the two groups were described by Kaplan-Meier method. Results:After propensity score matching,198 cases were in the EVAR group and 66 cases were in the OSR group.The ROC model showed that the best cut-off value of R value was 0.90,and the two groups were divided into two layers:R<0.90 and R≥0.90.Among them,112 patients with R<0.90 (84 cases of EVAR,28 cases of OSR);there were 152 patients with R≥0.90 (114 cases of EVAR and 38 cases of OSR).The follow-up time was (23.6±1.6) months (range:1 to 70 months).In the R≥0.90 stratification,the total mortality (26.3% vs.5.3%, χ2=7.600， P=0.006),complication rate (44.7% vs.26.3%, χ2=4.025， P=0.045), and secondary intervention rate (31.6% vs.13.2%, χ2=4.910， P=0.027) in the EVAR group were higher than those in the OSR group.In the R<0.90 stratification,there was no significant difference in the total mortality rate (13.1% vs.10.7%, χ2=0.109， P=0.741), complication rate (28.6% vs.35.7%, χ2=0.507， P=0.477) and secondary intervention rate (14.3% vs.21.4%, χ2=0.353， P=0.552) between the two groups. Conclusions:When R≥0.90 in IAAA patients,OSR maybe more beneficial to patients in terms of survival rate,postoperative complication rate and secondary intervention rate than EVAR.When R<0.90,there are no significant differences in survival rate,complication rate and secondary intervention rate between the two surgical methods.

Objective:To assess the efficacy and safety of computed tomography (CT)-guided percutaneous cryoablation in treating malignant liver tumors located explicitly at high-risk sites.Methods:Data were collected retrospectively from patients with malignant liver tumors undergoing percutaneous cryoablation at Tianjin Medical University Cancer Hospital between January 2018 and December 2021. In all, 46 patients with malignant liver tumors at non-high-risk sites were matched 1∶1 according to the maximum tumor diameter. Technical success rate, complete ablation rate, and complications at 12 and 24 months post-surgery were evaluated. A statistical analysis of the ablation effect difference between the high-risk site and non-high-risk site groups was conducted. Univariate and multivariate logistic regression analyses were performed to identify risk factors.Results:Both groups demonstrated a 100% intraoperative technical success rate, and no major complications related to cryoablation were observed. The complete ablation rate was 82.6% (38/46) and 71.7% (33/46) in the high-risk group and 84.8% (39/46) and 73.9% (34/46) in the non-high-risk group at 12 and 24 months, respectively. There was no significant difference in complete ablation rates between the two groups ( P>0.05). Multivariate analysis identified the distance between the tumor edge and high-risk site ≤5 mm and preoperative trans-arterial chemoembolization (TACE) treatment as independent risk factors for cryoablation effect. Conclusion:CT-guided percutaneous cryoablation is a safe and effective approach for patients with malignant liver tumor at high-risk sites. Our results emphasize the importance of proper preoperative planning and intraoperative manipulation.