Objective: To investigate the factors influencing intraoperative blood transfusion in patients with hip fractures and to develop a machine learning (ML) model for predicting this risk. Methods: A total of 424 patients with hip fractures who underwent surgical treatment between November 2022 and March 2025 in our hospital were selected. Key feature variables of intraoperative blood transfusion risk were identified using the Boruta algorithm. Four different ML algorithms—support vector machine (SVM), linear discriminant analysis (LDA), mixed discriminant analysis (MDA), and extreme gradient boosting (XGBoost)—were used to develop predictive models for intraoperative blood transfusion risk. The predictive performance of the four ML models were evaluated using accuracy, precision, receiver operating characteristic (ROC) curves, precision-recall curves (PRC), precision-recall gain curves (PRGC), and F1 scores. Shapley additive interpretation (SHAP) was used to interpret the final model. Results: Among the 424 patients, 77(18.2%) received intraoperative blood transfusion. The Boruta algorithm identified albumin (ALB), activated partial thromboplastin time (APTT), types of anesthesia, types of fracture, and hemoglobin (Hb) as key feature variables for predicting intraoperative blood transfusion risk. In model evaluation, the SVM model outperforms the other three models across multiple metrics, including the area under the receiver operating characteristic curve (AUC), recall, recall gain, accuracy, precision, F1 score, and the area under the precision-recall curve (PRC-AUC). The SVM model, interpreted and visualized based on SHAP values, effectively predicted intraoperative blood transfusion risk in patients with hip fracture. A visual online application was developed based on the SVM model (https://pbo-nomogram.shinyapps.io/blood/). Conclusion: Preoperative low ALB and Hb levels, prolonged APTT, general anesthesia, and intertrochanteric fractures are risk factors for intraoperative blood transfusion in hip fracture patients. The risk prediction model for intraoperative blood transfusion constructed based on the SVM algorithm has optimal performance, which provides new ideas and methods for the clinical early identification of hip fracture patients with high transfusion risk and the implementation of targeted interventions.

Inteins are unique protein insertion sequences capable of self-excision, enabling the covalent ligation of flanking extein peptides via amide bond formation. This process proceeds spontaneously without requiring external enzymes, cofactors, or chemical reagents, granting inteins exceptional biocompatibility and traceless performance in protein engineering applications. Split inteins represent a specialized and versatile subclass whose splicing domains are encoded by two separate gene fragments rather than a single continuous open reading frame. These fragments, known as the N-terminal (IntN) and C-terminal (IntC) split inteins, associate through non-covalent interactions including hydrophobic forces, hydrogen bonds, and van der Waals forces to assemble into an active three-dimensional structure, which then drives efficient extein ligation and enables protein trans-splicing. Protein trans-splicing mediated by split inteins has become a cornerstone for traceless protein ligation owing to its high specificity and irreversibility, fundamentally reshaping strategies for protein modification, assembly, and functional regulation. Compared with traditional chemical ligation methods, split intein systems require no complex chemical derivatization of peptide fragments and can operate efficiently at micromolar concentrations under physiological conditions, thus avoiding structural and functional damage caused by organic reagents. In contrast to enzymatic ligation tools such as sortase, split inteins eliminate the need for additional enzymes or cofactors, simplifying reaction systems, reducing costs, and minimizing non-specific side products. These distinctive advantages render split inteins highly promising for applications in chemical biology, synthetic biology, and biopharmaceutical development. In recent years, deepened mechanistic understanding has established structure-guided rational design as the primary approach to overcoming key limitations of split inteins, including intrinsic aggregation propensity, strict extein sequence dependence, and limited splicing efficiency. Bioinformatic tools have been used to identify aggregation-prone regions in the IntN fragment, and site-directed mutagenesis of hydrophobic residues, relocation of split sites, or removal of misfolding-prone sequences has substantially reduced in vitro aggregation and improved soluble expression and assembly activity. Rational engineering of catalytic residues and adjacent flexible loops has relaxed strict amino acid preferences at extein junctions, enhancing sequence tolerance and reducing the risk of functional impairment in target proteins. Consensus design based on multiple sequence alignments has yielded ultra-fast splicing variants such as Cfa DnaE and Cat-TerL, which exhibit significantly accelerated kinetics and improved tolerance to denaturing conditions. Meanwhile, advances in structural biology have further clarified the conformational dynamics and catalytic mechanisms of splicing, supporting the precise design of high-performance intein modules. On this basis, electrostatic interaction tuning and metagenomic screening have yielded multiple mutually orthogonal split intein pairs, enabling selective multi-fragment protein ligation and providing new routes for the efficient synthesis of large multi-domain functional proteins. With these engineered split inteins offering continuously improved performance and expanded applicability, protein trans-splicing has been widely applied in numerous cutting-edge areas of protein research and biomedicine. In gene delivery, split intein-based systems overcome the packaging limit of adeno-associated viral vectors, enabling the accurate reconstitution of large therapeutic proteins and base editors in target cells, thereby enhancing the efficacy and scope of gene therapy for genetic diseases. In internal protein sequence editing, split inteins mediate precise sequence replacement and modification in flexible regions or loops of target proteins, without the need for complex multi-step ligation and protein refolding involved in traditional protein semisynthesis. In protein-protein interaction studies, intein-mediated splicing covalently captures transient and weak intracellular complexes, enabling sensitive, high-throughput interaction detection and drug screening. In synthetic biology, conditionally controllable splicing systems support the construction of diverse intracellular and cell-surface biological logic gates for the precise regulation of cellular behavior. In mechanistic biochemical research, split inteins enable photocatalytic proximity labeling and site-specific tagging, allowing the preparation of homogeneous protein samples carrying precise post-translational modifications such as ubiquitination and polyglutamylation for chromatin interactome analysis and epigenetic studies. Moreover, covalent trapping strategies using split inteins stabilize transient enzymatic intermediates, providing unprecedented insights into molecular mechanisms such as nucleosome ubiquitination that are difficult to elucidate using conventional methods. This review systematically summarizes key technological advances in split inteins over the past decade, highlighting engineering strategies, mechanistic insights, and the development of orthogonal components. It comprehensively surveys emerging applications at the frontiers of protein research, analyzes current core challenges, and proposes future directions, particularly emphasizing artificial intelligence-driven de novo design and novel splicing pathways to break existing technical bottlenecks. By enabling traceless, efficient, and versatile protein manipulation, split inteins continue to serve as indispensable tools that drive innovation in protein engineering and fundamental life science research.

Objective To explore the impact of tumor-associated myeloid cell infiltration signatures on postoperative overall survival (OS) in patients with gastric cancer. Methods A retrospective analysis was performed on patients who underwent radical gastrectomy at Zhongshan Hospital, Fudan University from January 2005 to December 2019. Patients were randomly divided into a training set (n＝167) and an internal validation set (n＝168) at a 1:1 ratio. Meanwhile, 147 patients with gastric cancer treated at Zhongshan Hospital (Xiamen), Fudan University during the same period were enrolled as the external validation set (n＝147). Immunohistochemistry was used in all patients to evaluate the distribution characteristics of 18 immune markers in three regions of gastric cancer tissues, namely primary tumor (PT), invasive margin (IM), and normal tissue (NT). These markers include 11 myeloid cell markers (CD11b, CD33, CD11c, CD14, CD15, CD16, CD68, CD86, CD163, CD206, and CD66b) and 7 immune checkpoints (CD73, IDO, LAG3, PD-1, SIGLEC9, SIRPA, and TIM3). LASSO regression and Cox proportional hazards model were applied to screen immune markers associated with postoperative OS in gastric cancer patients, and a predictive model for 1-, 3-, and 5-year postoperative OS was established. Data from the internal and external validation set were used for internal and external verification of the predictive model. Receiver operating characteristic (ROC) curves were plotted and the area under the curve (AUC) was calculated to assess the discriminative ability of the model. Results In the training set, LASSO regression and Cox proportional hazards model identified 4 immune marker signatures (CD14_PT, CD15_PT, CD206_PT, and SIGLEC9_PT) to construct the predictive model. ROC curve analysis showed that the AUCs of the model for predicting 1-, 3-, and 5-year postoperative OS were 0.74, 0.75, and 0.84, respectively. When the model was applied to the internal and external validation sets, the AUCs for 1-, 3-, and 5-year postoperative OS were 0.74, 0.72, 0.72 (internal validation set) and 0.72, 0.71, 0.74 (external validation set), respectively. Cox multivariate regression analysis showed that the risk score was an independent risk factor for postoperative OS in patients with gastric cancer. Conclusion The model constructed based on LASSO-Cox regression exhibits good predictive performance and can effectively predict postoperative OS in gastric cancer patients, which may serve as a basis for intensive treatment of high-risk patients after surgery.

Objective:To investigate the differences in protein profile expression in serum samples from children with corona virus disease 2019（COVID-19）related encephalopathy and to explore the underlying mechanisms.Methods:From December 1,2022 to January 31,2023,28 children with COVID-19 who were admitted to the Department of Pediatric Intensive Medicine at Shandong Provincial Hospital Affiliated to Shandong First Medical University were collected,including 21 patients with encephalopathy(COVID-19 with encephalopathy group) and seven patients without encephalopathy(COVID-19 without encephalopathy group).Three children from each group were selected for serum proteomic analysis using tandem mass spectrometry labeling proteomics technology.Proteins were considered significantly different if the fold change was >1.2 or <0.8，with P<0.05.Bioinformatics analysis，including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes Pathway Enrichment were performed on differentially expressed proteins.Protein-protein interaction networks were analyzed using the STRING database.Selected proteins were further validated by enzyme-linked immunosorbert assay. Results:A total of 41 differentially expressed proteins were identified between the two groups.Among these，14 proteins were upregulated and 27 proteins were downregulated in COVID-19 patients with encephalopathy compared to those without encephalopathy.Bioinformatics analysis revealed that these proteins were primarily enriched in critical signaling pathways，including complement and coagulation regulation，neutrophil degranulation and activation，and platelet degranulation.Enzyme-linked immunosorbert assay validation confirmed significant differences in key coagulation-regulating proteins(von willebrand factor upregulated，serpin family F member 2 downregulated in COVID-19 patients with encephalopatly）between the two groups.Conclusion:Coagulation dysfunction may play a role in the development of COVID-19 associated encephalopathy in children，providing valuable insights for future research.

Objective:To explore the impact of National Metabolic Management Center (MMC) mode on the metabolic indexes in different age patients with type 2 diabetic mellitus (T2DM).Methods:A prospective study method was used. A total of 798 T2DM patients underwent the MMC mode management in Shanghai Punan Hospital of Pudong New District from May 2021 to August 2024 were selected. The patients followed the MMC one-stop diagnosis and treatment management service standards to enter the registration, treatment, examination and follow-up processes. The average follow-up time was 12.0 months. The glucose and lipid metabolism indexes, blood pressure and body mass index (BMI) before intervention and after receiving the intervention by MMC were measured. The glucose and lipid metabolism indexes included triacylglycerol, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose, 2 h postprandial blood glucose and glycated hemoglobin. The control rates of blood glucose, blood lipid, blood pressure and BMI were calculated after intervention.Results:The triacylglycerol, total cholesterol, LDL-C, fasting blood glucose, 2 h postprandial blood glucose and glycated hemoglobin after intervention in patients with T2DM were significantly lower than those before intervention: (1.75 ± 1.63) mmol/L vs. (2.08 ± 1.74) mmol/L, (4.37 ± 1.11) mmol/L vs. (4.88 ± 1.24) mmol/L, (2.47 ± 0.92) mmol/L vs. (2.92 ± 0.98) mmol/L, (6.54 ± 1.71) mmol/L vs. (8.12 ± 3.05) mmol/L, (9.04 ± 3.49) mmol/L vs. (12.10 ± 5.28) mmol/L and (6.89 ± 1.23)% vs. (8.85 ± 2.31)%, the HDL-C after intervention was significantly higher than that before intervention: (1.21 ± 0.31) mmol/L vs. (1.13 ± 0.29) mmol/L, and there were statistical differences ( P<0.01). The control rates of blood lipid and blood glucose after intervention in patients with T2DM were significantly higher than those before intervention: 54.6% (436/798) vs. 37.3% (298/798) and 62.0% (495/798) vs. 26.1% (208/798), and there were statistical differences ( P<0.01); there were no statistical differences in the control rates of BMI and blood pressure before intervention and after intervention ( P>0.05). In T2DM patients with age <50 years and from 50 to 59 years, the triacylglycerol, total cholesterol, LDL-C, fasting blood glucose, 2 h postprandial blood glucose and glycated hemoglobin after intervention were significantly lower than those before intervention, the HDL-C after intervention was significantly higher than that before intervention, and there were statistical differences ( P<0.05 or <0.01); the control rates of blood lipid and blood glucose after intervention were significantly higher than those before intervention, the patients with <50 years: 44.5% (114/256) vs. 27.7% (71/256) and 76.6% (196/256) vs. 28.9% (74/256), the patients with 50 to 59 years: 54.8% (86/157) vs. 28.0% (44/157) and 66.9% (105/157) vs. 24.8% (39/157), and there were statistical differences ( P<0.01); there were no statistical differences in the control rates of BMI and blood pressure between before intervention and after intervention ( P>0.05). In T2DM patients with age from 60 to 69 years, the triacylglycerol, total cholesterol, LDL-C, fasting blood glucose, 2 h postprandial blood glucose and glycated hemoglobin after intervention were significantly lower than those before intervention, and there were statistical differences ( P<0.05 or <0.01); there was no statistical differences in HDL-C before intervention and after intervention ( P>0.05); the control rates of blood lipid and blood glucose after intervention were significantly higher than those before intervention: 59.0% (177/300) vs. 47.3% (142/300) and 53.3% (160/300) vs. 25.7% (77/300), and there were statistical differences ( P<0.01); there were no statistical differences in the control rates of BMI and blood pressure before intervention and after intervention ( P>0.05). In T2DM patients with aged ≥70 years, the total cholesterol, LDL-C, 2 h postprandial blood glucose and glycated hemoglobin after intervention were significantly lower than those before intervention, and there were statistical differences ( P<0.05 or <0.01); there were no statistical difference in triacylglycerol, HDL-C and fasting blood glucose between before intervention and after intervention ( P>0.05); the control rate of blood glucose after intervention was significantly higher than that before intervention: 48.2% (41/85) vs. 22.4% (19/85), and there was statistical difference ( P<0.01); there were no statistical differences in the control rates of BMI, blood pressure and blood lipid between before intervention and after intervention ( P>0.05). Conclusions:The intervention based on MMC mode management could effectively improve the glucose and lipid metabolism in patients with T2DM, especially for patients with aged <70 years. However, additional health guidance is needed for patients with aged ≥ 70 years to further enhance their health benefits.

This study aims to investigate the anti-inflammatory and anti-apoptotic effects of total flavonoids of hawthorn leaves(TFHL)on lipopolysaccharide(LPS)-induced inflammatory injury in rat intestinal epithelial(IEC-6)cells,as well as the underlying mechanisms.An in vitro inflam-mation model was first established by treating IEC-6 cells with lipopolysaccharide(LPS).IEC-6 cells were then incubated with three concentrations of TFHL for 24 h prior to a further 24 h LPS treatment.RT-qPCR was used to quantify mRNA levels of the inflammatory genes COX-2 and iN-OS,while Western blotting was used to assess protein levels of the apoptotic markers Bax,cleaved Caspase-3,Bcl-2,and the JNK/p-JNK signaling pathway.Finally,cells were pretreated with TFHL and/or the JNK inhibitor SP600125 for 24 h before LPS exposure for 24 h,in order to evaluate the combined effects of TFHL and SP600125 on LPS-induced inflammatory cytokine expression and apoptotic protein levels in IEC-6 cells.The results showed that,compared with the LPS group,the mRNA level of COX-2 and iNOS in the 2.5,5.0,10.0 mg/L TFHL group and the Bax and Caspase-3 protein levels decreased significantly(P＜0.01),and the Bcl-2 protein level was significantly higher(P＜0.01),p-JNK protein level and p-JNK/JNK ratio decreased significantly(P＜0.01);compared with the LPS group,the COX-2 and iNOS mRNA levels of the TFHL+LPS group de-creased significantly(P＜0.01),Bax,and Caspase-3 protein levels decreased significantly(P＜0.01),and the level of Bcl-2 protein increased significantly(P＜0.05);compared with the LPS group,the COX-2 and iNOS mRNA levels of the TFHL+SP600125 group decreased significantly(P＜0.01),Bax and Caspase-3 protein levels decreased significantly(P＜0.01),and Bcl-2 protein level increased significantly(P＜0.01).These findings indicate that TFHL exerts anti-inflammato-ry and anti-apoptotic effects in LPS-challenged IEC-6 cells by inhibiting the JNK signaling path-way.

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.

OBJECTIVE To summarize the procedural management practice of hospital infection review for new medical technologies and projects so as to provide references for other medical institutions.METHODS The data with the respect to review of new technologies and projects were collected from Zhejiang Provincial Hospital of Chinese Medicine between 2018 and 2023,and the process of review and management practice were summarized.The potential risk for infection was evaluated by establishing the evaluation indexes for nosocomial infection man-agement of new technologies and projects and conducting procedural management of the review so as to make clear of the corresponding prevention and control measures.The tracking closed-loop management was carried out for the new technologies and projects that have been already implemented.RESULTS Totally 629 items of new medical technologies and projects were involved in the review and tracking closed-loop management,including 499(79.33％)medical technologies and pharmacy-related projects and 130(20.67％)nursing.The result of review showed that there were 606(96.34％)items with'approval',14(2.23％)items with'approval after revision',3(0.48％)items with'approval after reexamination,and 6(0.95％)items with'disapproval'.The result of risk as-sessment indicated that there were 5(0.79％)items of high-risk projects and 624(99.21％)items of low-risk pro-jects.There was no severe nosocomial infection or infection cluster incident during the tracking of clinical applica-tion of the approved items.CONCLUSION The risk of nosocomial infection has been controlled from the origin through the practice,which further standardizes the clinical application of the new technologies and projects and provides evidence for normalized application of the new technologies and projects in the medical institutions.

Objective To investigate correlations of the ratio of specific brain region volume to total brain volume(ratio％),standard uptake value(SUV)of specific brain region based on 18F-FDG PET/MR examination in Alzheimer disease(AD)patients,as well as the relationship between changes of these two.Methods Fifty AD patients were retrospectively collected.Based on FDG PET/MR,the ratio％and the mean SUV(SUVmean)of 40 specific brain regions were obtained,and the correlation between ratio％and SUVmean for each region were evaluated.According to a database of normal brains,Z-scores for ratio％and SUVmean were calculated to represent structural and functional changes in AD patients,and the correlation between these 2 Z-scores was assessed.Results Correlations were found between ratio％and SUVmean,also between Z-scores of these two parameters in 29 brain regions(r=0.288 to 0.778,all P＜0.05).Among them 7 brain regions,i.e.bilateral middle temporal gyrus,right fusiform gyrus,right hippocampus,right precuneus,left lingual gyrus and right parahippocampal gyrus exhibited correlation coefficients greater than 0.6.Conclusion There were some relationships between brain structural and metabolic functions and their changes in AD patients showed on FDG PET/MR.

Medical therapy and surgical intervention are the two primary approaches for treating myocardial bridge.However,there remains controversy regarding the use of coronary artery bypass grafting(CABG)and myocardial bridge unroofing.Here,we report a case of myocardial infarction following CABG in a patient with a myocardial bridge.The patient was admitted to Lanzhou First Peopie's Hospital with persistent chest pain,chest tightness,and shortness of breath lasting 2 hours.Physical examination revealed no significant abnormalities.Electrocardiography(ECG)indicated extensive anterior wall myocardial infarction.Laboratory findings showed myoglobin levels of 140.1 ng/ml and troponin Ⅰ levels of 2.59 ng/ml,with no other significant abnormalities.The initial diagnosis was acute extensive anterior wall myocardial infarction.Emergency coronary angiography revealed a myocardial bridge in the mid-segment of the left anterior descending artery(LAD).Emergency CABG using the left internal mammary artery to the LAD was performed,leading to symptomatic improvement,and the patient was discharged in stable condition.However,the patient experienced a recurrent myocardial infarction seven years post-surgery and received secondary preventive medical therapy.The patient is currently under ongoing follow-up care.CABG is an effective treatment for myocardial bridge.However,based on the case reported in this study,we recommend careful evaluation of whether a patient may benefit from CABG.