Randomized controlled trials have long been regarded as the gold standard for evaluating vaccine efficacy. However, conducting randomized controlled trials to assess vaccines in real-world settings is often impractical due to limitations in research resources and ethical considerations. In recent years, the emulated target trial has emerged as a novel methodological framework that applies the design principles of randomized trials to observational studies. By using observational data to emulate the randomization and treatment assignment of a clinical trial, this approach enables the evaluation of vaccine effectiveness in the real world. The application of emulated target trials enhances the quality and applicability of real-world evidence. This article explains the fundamental principles, design elements, advantages, and limitations of using emulated target trials to evaluate vaccine effectiveness, providing methodological guidance for conducting such studies in China.

Objective:To analyze and compare the interfractional setup errors between two body posi-tioning fixation methods(lithotomy position with carbon fiber full-body fixation frame vs.conventional carbon fiber body fixation frame combined with thermoplastic membrane)in radical radiotherapy for pros-tate cancer,and to calculate the clinical target volume(CTV)to planning target volume(PTV)margin(MPTV)for both methods to optimize immobilization techniques and radiotherapy workflows.Methods:A retrospective analysis was conducted on 37 consecutive patients who underwent radical prostate radio-therapy at Peking University First Hospital between August 2021 and March 2023.The patients were di-vided into two groups based on the immobilization method:Group A(18 patients,450 CBCT image sets)used a carbon fiber whole-body fixator in the lithotomy position,while Group B(19 patients,461 CBCT image sets)used a conventional carbon fiber fixator combined with a thermoplastic mask.All the patients underwent daily cone-beam computed tomography(CBCT)image guidance.Bone registration combined with manual registration was used to obtain the setup error data in the left-right(X),cranio-caudal(Y)and anterior-posterior(Z)directions.The positioning errors of the two groups were compared by using the independent sample t-test,the Mann-Whitney U test and the chi-square test.The average positioning error,systematic positioning error(Σ)and random positioning error(δ)were calculated,and the CTV-PTV extension distance was calculated by using the(MPTV=2.5Σ+0.7δ).Results:The analysis of the setup errors in the three-dimensional direction showed significant differences between the two groups(all P＜0.01).Specifically,the median(quartile)absolute values of the errors in the X,Y,and Z di-rections of group A were[0.40(0.20,0.70)cm,0.50(0.30,0.80)cm,and 0.35(0.20,0.60)cm],respectively.In group B,the corresponding values were significantly reduced to[0.20(0.10,0.40)cm,0.40(0.20,0.70)cm and 0.20(0.10,0.40)cm].The results of Mann-Whitney U test showed that the differences in each direction were highly statistically significant(X:z=-6.86;Y:z=-2.76;Z:z=-5.71).The cumulative distribution ratio of the setup error displacement within 0.5 cm in the X,Y,and Z directions in group A and group B were 297(66.0％)and 408(88.5％)(P＜0.01),250(55.6％)and 285(61.8％)(P=0.055),308(68.4％)and 391(84.8％)(P＜0.01),re-spectively.The CTV-PTV margins in three directions were X 0.66 cm in group A and 0.35 cm in group B;Y0.67 cm and 0.45 cm;Z 0.54 cm and 0.42 cm.Conclusion:Conventional carbon fiber human body fixator combined with thermoplastic film can significantly reduce the setup error.However,the car-bon fiber whole-body fixator in the lithotomy position demonstrated larger setup errors in the X,Y,and Z directions compared with the conventional fixator combined with a thermoplastic mask,indicating the need for further workflow optimization.Given that the lithotomy position is essential for transperineal ultrasound-guided techniques,further research and improvements are required to achieve higher positioning accuracy.

Objective: To establish and validate a whole blood (WB) supply model, thereby providing practical experience for the clinical application of WB in domestic trauma emergency care and informing the development of a wartime blood supply system for the military. Methods: A “10×24” WB supply model was established by formulating blood collection protocols, storage standards, and transfusion criteria. Multiple WB samples were tested under specific storage conditions to assess key indicators at different time points, including red blood cell (RBC), white blood cell (WBC), and platelet counts, hemoglobin concentration, coagulation parameters (PT, APTT, TT, FIB), coagulation factor activity, thromboelastography (TEG) parameters, and electrolyte levels. Additionally, clinical data from hemorrhagic patients who met the criteria for WB transfusion and were admitted between March and July 2024 were analyzed to evaluate WB transfusion volume. Results: RBC counts and hemoglobin levels remained stable in WB stored at 4℃ for up to 10 days. However, platelet counts and coagulation function (PT, APTT) significantly declined with prolonged storage, while potassium levels increased. From March to July 2024, the model was successfully applied to 23 patients with acute hemorrhage, with a median WB transfusion volume of 543 mL. A detailed case study of a severe traumatic hemorrhagic shock patient was reported, who was successfully treated with 5.5 units of refrigerated WB combined with component blood. Conclusion: The “10×24” WB supply model demonstrated acceptable changes in critical quality parameters under strict management and a 10-day rotation cycle. This model effectively supports the treatment of acute hemorrhage and holds promise for integration into the future wartime blood supply system of the military.

Objective To find the molecular mechanism underlying the effect of congenital cataract related 129th single-site mutation G129C on the thermal stability of human γC crystallin(HγC)protein structure.Methods HγC-WT and HγC-G129C were expressed and purified in vitro.The changes of intrinsic fluorescence intensity and static light scattering intensity of proteins with temperature were measured,and the temperature dependence of the folding and aggregation structures of HγC-WT and HγC-G129C was compared.Results When temperature was be-low 65 ℃,the barycentric mean of the intrinsic fluorescence of HγC-WT and HγC-G129C shifted towards a longer wavelength and the fluorescence intensity decreased with the increasing temperature,which was believed to be the evidence of unfolded protein conformation.When the temperature was higher than 65 ℃,the static light scattering intensity increased significantly with the temperature,indicating the protein aggregation upon heating.The wild-type HγC-G129C showed a stronger aggregation potency.During the thermal de-naturation process of HγC-WT and HγC-G 129C,the crossing-point temperatures were 74.5 ℃ and 55.5 ℃,respectively.HγC-WT showed higher thermal stability.Conclusions The congenital cataract-associated G129C mutation significantly weakens conforma-tional stability of γC-crystallin.

Objective:To develop and validate a clinical prediction model for assessing the risk of postoperative pulmonary complications (PPCs) in elderly patients undergoing surgery with general anesthesia.Methods:This prospective observational study enrolled patients aged ≥65 years who underwent general anesthesia with mechanical ventilation duration >3 hours across six tertiary hospitals between December 2022 and August 2023. Based on follow-up outcomes (until discharge or postoperative day 7), patients were categorized into a non-PPCs group and a PPCs group. Detailed records included baseline patient characteristics, preoperative comorbidities, surgical information (type, duration), and bedside lung ultrasound scores (LUS) assessed within 24 hours postoperatively using a standardized 12-zone protocol. Predictor selection was performed using LASSO regression. Significant predictors identified were incorporated into a multivariate logistic regression analysis to build the prediction model, visualized as a nomogram. Internal validation was conducted via bootstrap resampling (1 000 repetitions). Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) for discrimination, calibration curves for calibration accuracy, and decision curve analysis (DCA) for clinical utility.Results:A total of 130 eligible elderly surgical patients were included. PPCs occurred in 17 patients (incidence rate: 13.1%). Multivariate analysis identified LUS ( OR=1.248, 95% CI: 1.099-1.417, P=0.001) and elective surgery type ( OR=0.206, 95% CI: 0.043-0.988, P=0.048) as independent predictors of PPCs. The nomogram model demonstrated an AUC of 0.867 (95% CI: 0.775-0.959) upon initial testing. Internal validation confirmed good discrimination (AUC=0.863, 95% CI: 0.778-0.972). Calibration curves indicated excellent agreement between predicted probabilities and observed outcomes. Decision curve analysis demonstrated significant clinical net benefit across a wide range of threshold probabilities (0.03-0.89). Conclusions:The clinical prediction model, developed using early postoperative LUS scores and surgical type, effectively predicts the risk of postoperative pulmonary complications in elderly patients following surgery under general anesthesia. The model exhibits strong discrimination, calibration, and clinical utility, providing clinicians with a reliable tool for individualized risk assessment to support clinical decision-making and potentially reduce PPC incidence.

Objective:To investigate the role of calcium-binding protein S100A9 in acute lung injury induced by hepatic ischemia-reperfusion (HIR) in mice, and to explore its relationship with nuclear factor erythroid 2-related factor 2 (Nrf2).Methods:A total of 12 specific pathogen-free (SPF) male wild-type (WT) and 12 S100A9 knockout (S100A9 KO) C57BL/6J mice aged 6~8 weeks and weighing 20-25 g were randomly divided into four groups using a random number table: WT+Sham group, S100A9 KO+Sham group, WT+HIR group, and S100A9 KO+HIR group ( n=6 per group). The HIR model was established by clamping the portal vein and hepatic artery of the left and median liver lobes for 60 minutes followed by reperfusion. At 6 hours post-reperfusion, mice were anesthetized again, and blood samples were collected from the inferior vena cava. Both lungs were harvested. The lung wet-to-dry (W/D) weight ratio was measured. Hematoxylin and eosin (HE) staining was used to assess histopathological changes and calculate lung injury scores. The levels of inflammatory markers—S100A9, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) —as well as oxidative stress indicators including myeloperoxidase (MPO), reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) in serum and lung tissue were measured. Western blotting was used to assess the expression levels of nuclear and cytoplasmic Nrf2, and cytoplasmic HO-1. Results:Compared with the WT+Sham group, both the WT+HIR and S100A9 KO+HIR groups showed significantly increased lung injury scores, W/D ratio, TNF-α, IL-6, ROS, MPO, and MDA levels (all P<0.05). Compared with the WT+HIR group, the S100A9 KO+HIR group exhibited significantly reduced levels of these indicators (all P<0.05). Moreover, the S100A9 KO+HIR group showed elevated nuclear Nrf2 expression and decreased cytoplasmic Nrf2 expression, accompanied by increased expression of HO-1, Gclm, Gclc, and Nqo1 (all P<0.05). Conclusion:Upregulation of S100A9 is involved in the development of HIR-induced acute lung injury, possibly through inhibition of Nrf2 nuclear translocation.

Objective:To evaluate the acute toxicities and related influencing factors of vertebral-body-sparing proton craniospinal irradiation (VBSpCSI) using pencil beam scanning (PBS) technology in pediatric patients, and to assess spinal growth and survival outcomes.Methods:A retrospective analysis was conducted on 70 pediatric patients treated with PBS-based VBSpCSI at Hebei Yizhou Cancer Hospital between January 2020 and December 2022, and continued to follow up until November 2023. Acute toxicities were assessed, and linear regression analysis combined with receiver operating characteristic curve were employed to investigate the dose-effect relationship between vertebral dose and toxicities. Spinal growth after radiotherapy was evaluated by measuring the Cobb angle on follow-up MRI. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method.Results:The median age of patients at the time of irradiation was 6 years (range, 2-16 years). Two patients (3%) developed grade ≥3 gastrointestinal toxicities, while 7 patients (10%) experienced grade 1 radiation-induced esophagitis. The nadirs of white blood cell count (WBC), absolute neutrophil count (ANC), and absolute lymphocyte count (ALC) during treatment were significantly negatively correlated with vertebral V 5 Gy ( P=0.009, 0.006, 0.001) and vertebral V 20 Gy ( P=0.007, 0.011, <0.001). When vertebral V 5 Gy<86.5% and vertebral V 20 Gy<73.2%, the incidence of grade ≥3 myelosuppression was significantly reduced ( P<0.001, =0.001). Additionally, younger patient age (in months) and concurrent chemotherapy were also significantly associated with increased acute hematologic toxicity. Among 43 patients with MRI follow-up, no scoliosis, kyphosis, or chronic lumbosacral pain was observed. The 3-year OS and PFS rates were 95.7% and 86.4%, respectively. Conclusions:PBS-based VBSpCSI in pediatric patients demonstrates manageable acute toxicities, with a clear dose-effect relationship between vertebral V 5 Gy , V 20 Gy and hematologic toxicities, and the incidence of non-hematological toxicities remains low. No adverse effects on spinal growth or survival outcomes were observed in the short term.

BACKGROUND:Electrical stimulation is an effective treatment plan for peripheral nerve injuries,but different frequencies of electrical stimulation have different mechanisms and applications for promoting peripheral nerve recovery.OBJECTIVE:To systematically sort out and summarize the roles and applications of different frequencies of electrical stimulation in the treatment of peripheral nerve injuries,and to deeply analyze the advantages and disadvantages of various methods in order to find the most beneficial treatment strategy for patients'nerve recovery.METHODS:Computer-based searches were conducted in the China National Knowledge Infrastructure(CNKI)and PubMed databases from the inception of the databases to May 2024.The search terms included"peripheral nerve injury,electrical stimulation,low frequency electrical stimulation,medium frequency electrical stimulation,high frequency electrical stimulation,TENS,interfering electricity,short wave,ultrashort wave,frequency"in both English and Chinese.Ultimately,74 relevant documents were included for analysis.RESULTS AND CONCLUSION:Peripheral nerve injury,a common clinical disease,can cause sensory and motor dysfunction in patients.Low-frequency electrical stimulation can promote cell proliferation and accelerate the expression of nerve growth factor within the cell after electrical stimulation,promote macrophage recruitment and infiltration,accelerate the clearance of myelin debris,and promote myelin regeneration of damaged axons.Medium-frequency electrical stimulation can act on deeper tissues and is better for relieving neuropathic pain.High-frequency electrical stimulation can promote the proliferation of Schwann cells and macrophages,inhibit inflammatory factors,and rapidly recruit cells to the site of nerve injury,accelerating the speed of nerve repair.Different frequencies of electrical stimulation have their own advantages in promoting the recovery of peripheral nerve injuries,but there are still some issues,such as differences in the site of electrical stimulation and the treatment plans for various disease types.

Objective To develop a refined management model for operating rooms and assess its clinical impact on op-erational efficiency and cost control.Methods The study included 10,728 elective surgeries from January to June 2024 as the study group and 9 414 elective surgeries from January to June 2023 as the control group.The differences in operational metrics before and after implementing the refined management model were compared.The model was developed through comprehensive management by hospital leadership and multi-department collaboration,focusing on management structure,systems,processes,information technology,and resource allocation.Results In terms of efficiency,the on-time start rate of the first surgeries in the study group was significantly higher than in the control group(P＜0.05).The turnover time between surgeries was shorter in the study group(P＜0.01),and the rate of unexpected surgery cancellations was lower(P＜0.01).The average cost per surgery for consumables,excluding the impact of centralized procurement of consumables,was approximately 971 yuan,representing an 11% reduction compared to the previous year,despite a 14% increase in surgical volume.The average daily operating cost per operating room was about 12 303 yuan,a 7% reduction.Economic benefits increased by 8.43 million yuan,a 38% year-on-year increase.Conclusion Implementing a refined management model in operating rooms can significantly enhance efficiency,re-duce costs,and achieve dual improvements in social and economic benefits.