Cone-beam computed tomography (CBCT) is widely used in dentistry, surgery, radiotherapy and other medical fields. However, repeated CBCT scans expose patients to additional radiation doses, increasing the risk of secondary malignant tumors. Low-dose CBCT image reconstruction technology, which employs advanced algorithms to reduce radiation dose while enhancing image quality, has emerged as a focal point of recent research. This review systematically examined deep learning-based methods for low-dose CBCT reconstruction. It compared different network architectures in terms of noise reduction, artifact removal, detail preservation, and computational efficiency, covering three approaches: image-domain, projection-domain, and dual-domain techniques. The review also explored how emerging technologies like multimodal fusion and self-supervised learning could enhance these methods. By summarizing the strengths and weaknesses of current approaches, this work provides insights to optimize low-dose CBCT algorithms and support their clinical adoption.
Cone-Beam Computed Tomography/methods* ; Deep Learning ; Humans ; Algorithms ; Image Processing, Computer-Assisted/methods* ; Radiation Dosage ; Artifacts

Traditional development of small protein scaffolds has relied on display technologies and mutation-based engineering, which limit sequence and functional diversity, thereby constraining their therapeutic and application potential. Protein design tools have significantly advanced the creation of novel protein sequences, structures, and functions. However, further improvements in design strategies are still needed to more efficiently optimize the functional performance of protein-based drugs and enhance their druggability. Here, we extended an evolution-based design protocol to create a novel minibinder, BindHer, against the human epidermal growth factor receptor 2 (HER2). It not only exhibits super stability and binding selectivity but also demonstrates remarkable properties in tissue specificity. Radiolabeling experiments with ^99mTc, ⁶⁸Ga, and ¹⁸F revealed that BindHer efficiently targets tumors in HER2-positive breast cancer mouse models, with minimal nonspecific liver absorption, outperforming scaffolds designed through traditional engineering. These findings highlight a new rational approach to automated protein design, offering significant potential for large-scale applications in therapeutic mini-protein development.

Space medicine,as a comprehensive discipline ensuring the safety,health,and efficient performance of astronauts during manned space missions,focuses on elucidating the underlying mechanisms of multi-system physiological effects induced by extreme space environments and developing corresponding protective strategies.With China's space program transitioning into an application and development phase,space medical experiments—a critical domain within space applications—face significant opportunities and challenges.This paper reviews the international development trend in the field of medical experiments and the progress in China from perspectives including platform system construction,utilization of novel technologies,and scientific discoveries.It further outlines the engineering framework,guiding ideology,and key research directions for space medical experiments under China's Space Station Application and Development Project.Deliberations and prospects center on the in-depth analysis of the adaptation law of life in space flight,the application of big data and artificial intelligence technology,the emerging challenges it faces,and the scientific research organization models.This work aims to provide a reference for the development of space medical experiment field in China.

Objective To explore the effect of transjugular intrahepatic portosystemic shunt(TIPS)on gut microbiota and blood ammonia level in patients with decompensated cirrhosis,and to analyze the correlation between the gut microbiota and blood ammonia level.Methods From July 2021 to December 2023,the patients with decompensated cirrhosis and portal hypertension complicated by esophagogastric variceal bleeding and/or refractory ascites,who received TIPS at Zhuhai Hospital of Guangdong Provincial Hospital of Traditional Chinese Medicine,were collected.The blood and stool samples were collected before and after TIPS.The changes in blood routine,prothrombin time,liver function,and blood ammonia level were determined.The change of gut microbiota was detected using 16S rRNA high-throughput sequencing,and Spearman correlation analysis was used to assess the correlation between the gut microbiota and blood ammonia level.Results In 20 patients,the post-TIPS one-month levels of AST,TBil,DBiL,PT,and blood ammonia were higher than their pre-TIPS values(P＜0.05),and the albumin(Alb)level was lower than the pre-TIPS value(P＜0.05).The post-TIPS 3-month levels of TBil,DBil,PT,and blood ammonia were higher than their pre-TIPS values(P＜0.05).One month after TIPS,the beta diversity of the gut microbiota became significantly different from the pre-TIPS pattern(P＜0.05).After TIPS,the harmful bacteria such as Veillonella,Streptococcus and Haemophilus were significantly reduced,the difference was statistically significant(P＜0.05).The correlation analysis of gut microbiota and blood ammonia level showed that in T0 group Colidextribacter was positively correlated with blood ammonia level,while Roxobella was negatively correlated with blood ammonia level;and in T1 group,Colidextribacter and Streptococcus were positively correlated with blood ammonia level,while Coprococcus,Bifidobacterium and Parasutterella were negatively correlated with blood ammonia level,and the differences were statistically significant(all P＜0.05).Conclusion In patients with decompensated cirrhosis after receiving TIPS,significant changes in the pattern of gut microbiota occur.Certain correlations exist between the changes of some microbiota and blood ammonia levels.Regulating the intestinal microecology may contribute to reducing blood ammonia level after TIPS.

【Objective】 To analyze the predictive value of serum β-defensin-3 (HBD-3) and decoy receptor 3 (DCR3) for urinary tract infection after percutaneous nephrolithotomy (PCNL) in patients with complex kidney calculi. 【Methods】 A prospective study was conducted on 112 patients treated with PCNL at our hospital during Jan.2020 and Dec.2022.The patients were divided into the non-infection group (52 cases) and infection group (60 cases).The general data, HBD-3 and DCR3 levels of the two groups were compared.Receiver operating characteristic (ROC) curve was drawn to analyze the predictive value of C reactive protein (CRP), procalcitonin (PCT), HBD-3 and DCR3 levels for postoperative urinary tract infection. 【Results】 Compared with the non-infection group, the infection group had higher levels of HBD-3 [(0.77±0.08) ng/mL vs. (1.36±0.25) ng/mL, P=0.001] and DCR3 [(4.68±0.53) ng/mL vs.(13.21±0.28) ng/mL, P=0.001].Multivariate logistic regression showed that a history of urinary tract surgery, preoperative urinary tract infection, operation time, catheterization time, stone load, type of antibiotics, concomitant renal dysfunction, intraoperative channel type, CRP, PCT, HBD-3 and DCR3 were risk factors of postoperative urinary tract infection (P<0.05).The ROC curve showed that the accuracy of CRP, PCT, and CRP plus PCT were 70.54%, 72.32%, and 78.57%, respectively; the accuracy of HBD-3, DCR3, and HBD-3 plus DCR3 were 69.64%, 75.89%, and 86.61%, respectively. 【Conclusion】 Postoperative urinary tract infection in patients with complex kidney calculi is associated with multiple factors, especially high expression levels of HBD-3 and DCR3.Combined detection has high predictive value.

Objective:To analyze human factors in radiotherapy safety incidents and identify their correction for the purpose of mining the latent incident chains.Methods:A total of 60 radiotherapy safety incidents were included in the Radiation Oncology Incident Learning System (ROILS) for cause identification and frequency statistics using the Human Factors Analysis and Classification System (HFACS). Latent class analysis (LCA) was performed for the result to correlate the incident causes.Results:Incidents in the protocol design stage were the most common, accounting for 35%. Adverse organizational climate, inadequate supervision, and personnel factors were the primary causes of incidents at each level of the HFACS, accounting for 4.66%, 15.68%, and 16.20%, respectively. Three latent incident chains were identified through LCA, comprising two originating from organizational climate issues and one from organizational process issues, which were passed down via various human factors or " loopholes"Conclusions:HFACS assists in tracing the human factors at all levels that lead to radiotherapy safety incidents. The high-frequency causes and three latent chains of radiotherapy incidents found in this study can provide a guide for the development of targeted safety and defense measures.

Objective:To investigate the dosimetric effects of complex cardiac-respiratory motion in cardiac stereotactic body radiotherapy (CSBRT).Methods:A cardiac motion phantom was employed to simulate patient-specific cardiac-respiratory motion in 10 cases. The measured doses obtained under the phantom motion state were compared with the calculated doses in radiotherapy treatment planning for clinical patients. Moreover, 18 groups of design-based cardiac-respiratory motion were simulated. The radiation doses under the phantom motion state were measured using radiochromic films and compared with those under the resting state.Results:In the patient-specific cardiac-respiratory motion group, the gamma passing rate (GPR) under the 3%/2 mm standard between the measured and the calculated doses was 90.0% ± 7.0%. The correlation coefficient of the respiratory motion amplitude in the superior-inferior (SI) dimension with the GPR was -0.86 ( P=0.01). In the design-based cardiac-respiratory motion groups, the increase in the amplitude of cardiac-respiratory motion reduced the consistency between the dynamic dose and the static reference dose. Especially, the increase in the respiratory motion amplitude produced the most pronounced effect, reducing the width of the 90% isodose line in the respiratory motion direction, with a mean slope of -1.6. Additionally, the increase in the penumbra corresponds to a mean slope of 1.4. Conclusions:The respiratory motion amplitude serves as a primary factor influencing the dose accuracy of CBSRT. The characteristics and dosimetric effects of cardiac-respiratory motion are patient-specific, thus necessitating the assessment of cardiac-respiratory motion characteristics before CBSRT to individualize the application of motion management techniques for enhanced treatment accuracy.

Objective:To investigate the dosimetric feasibility of cardiac stereotactic body radiotherapy (CSBRT) using volumetric-modulated arc radiotherapy (VMAT)-like technique on the Unity MR-linac.Methods:A retrospective analysis was conducted on 12 refractory arrhythmia patients who underwent CSBRT at West China Hospital, Sichuan University, from April 2021 to December 2022. Four different treatment plans were designed for each patient based on the average phase of 4DCT: VMAT plan based on a linear accelerator, VMAT-like plan with magnetic field based on Unity, VMAT-like plan without magnetic field based on a Unity, and static intensity-modulated radiation therapy (IMRT) plan with 7 beams based on Unity. The VMAT-like plans used static IMRT beams evenly distributed at 30 angles. Evaluation metrics included conformity index (CI), homogeneity index (HI), gradient index (GI), dosimetric parameters of organs at risk (OAR), optimization time, and monitor unit (MU). These metrics among groups were analyzed using the Wilcoxon paired signed-rank test.Results:The CI of the VMAT plan was better than that of the VMAT-like plan with magnetic field (0.84 vs. 0.81, P=0.005). The GI of the VMAT-like plan without magnetic field was significantly lower than that of VMAT-like plan with magnetic field ( P=0.015). The CI and HI of the IMRT plan were both inferior to VMAT-like plan with magnetic field ( P=0.034). The average dose to the heart and lungs in VMAT-like plan with magnetic field was higher than those in the VMAT plan and VMAT-like plan without magnetic field (both P<0.05). The magnetic field significantly increased the dose to the skin, tissue-lung interface, and outside the margins (all P<0.05). The optimization time of the VMAT-like plan with magnetic field was longer than that of the IMRT plan, but it required fewer MUs ( P=0.001). The quality of the IMRT plans was poor and did not meet clinical requirements. Conclusion:The quality of CSBRT plans based on VMAT-like techniques meets clinical requirements, but attention must be paid to the dosimetric effects of the magnetic field.

Objective:To investigate the efficacy of the Scarf osteotomy in treating adolescents with metatarsus adductus-type hallux valgus.Methods:A retrospective analysis was conducted on 20 patients (30 feet) treated with the Scarf osteotomy for metatarsus adductus-type hallux valgus at the Department of Hand and Foot Surgery, Beijing University of Chinese Medicine Third Affiliated Hospital, from July 2022 to August 2023. This group included 10 patients with bilateral conditions and 10 with unilateral, comprising 4 males and 16 females, with an average of 16.2±2.4 years (range, 14-19 years). The procedure involved the release of the lateral capsule, sesamoid ligaments, and adductor hallucis before osteotomy. After osteotomy, shortening and wedge resection were performed, along with translation and rotation of the distal osteotomy to reposition the first metatarsal beside the second and thereby reduce metatarsus adductus. The outcomes included preoperative, immediate postoperative, and final follow-up angles: hallux valgus angle (HVA), intermetatarsal angle (IMA), metatarsal adduction angle (MAA), and the angle between the second to fifth metatarsals.Results:All 20 patients successfully underwent surgery with good wound healing and no infections; the average clinical healing time of osteotomy site was 5.1±0.7 weeks (range, 4.1-6.6 weeks). Follow-up lasted for 12.0±5.4 months (range, 2-18 months). Significant differences were observed in HVA, which was from 35.40°±5.45° preoperatively to 6.93°±3.60° immediately postoperatively, and 9.83°±2.65° at final follow-up; IMA, which was from 11.50°(9.75°, 14.00°) preoperatively to 1.50°(0.00°, 2.00°) immediately postoperatively, and at final follow-up; MAA, which was from 22.80°±2.60° preoperatively to 20.63°±2.27° immediately postoperatively, and 20.67°±2.20° at final follow-up; the angle between the second to fifth metatarsals,which was from 19.03°±1.85° preoperatively to 15.37°±1.33° immediately postoperatively, and 16.03°±1.73° at final follow-up. Visual analogue scale (VAS) also significantly decreased from 2.60±1.64 preoperatively to 1.30±0.92 at 6-8 weeks postoperatively. No cases of transfer metatarsalgia or recurrence of hallux valgus were reported.Conclusion:The Scarf osteotomy for metatarsus adductus-type hallux valgus effectively corrects the first metatarsal adduction and improves the adduction state of the remaining metatarsals to various degrees.

Purpose/Significance To summarize the common dimensions of data quality evaluation,and to expound the types and characteristics of medical big data quality evaluation and management methods,so as to provide references for medical big data quality e-valuation and management.Method/Process The paper reviews domestic and foreign medical big data quality related literature,and em-phatically analyzes medical big data quality evaluation dimensions,methods and management.Result/Conclusion Data quality standards are conducive to standardized management of medical big data.A scientific and reasonable medical big data quality evaluation system and a whole-process data quality management system in line with national conditions in China should be established and improved as soon as possible to promote the development and application of medical big data in our country.