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 investigate the correlation of dietary lipid intake and apolipoprotein with Helicobacter pylori (Hp) infection combined with gastric mucosal lesions. Methods A retrospective analysis was conducted on 320 patients diagnosed with Hp infection during physical examinations from March 2024 to March 2025. The daily dietary lipid intake of all patients was statistically analyzed. The levels of apolipoprotein A1‌ (Apo-A1) and apolipoprotein B‌ (Apo B) were detected. Logistic regression was used to analyze the risk factors influencing Hp infection combined with gastric mucosal lesions. Results Compared with the non-gastric mucosal lesion group, patients in the gastric mucosal lesion group had higher daily dietary lipid intake, lower Apo-A1, higher Apo B, and higher proportion of family history of gastric cancer (P<0.05). Logistic regression analysis revealed that daily dietary lipid intake, low level of Apo-A1, and high level of Apo B were independent risk factors of Hp infection with gastric mucosal lesion (P<0.05). Conclusion Daily dietary lipid intake, Apo-A1, and Apo B are closely related to Hp infection with gastric mucosal lesion. For patients with high daily dietary lipid intake, decreased Apo-A1 level, increased Apo B level, and complicated Hp infection, it is necessary to further screen gastroscopy to determine whether gastric mucosal lesion occurs.

ObjectiveTo investigate the independent risk factors for concurrent myocardial injury before intervention in patients with primary hepatic carcinoma （PHC）， to construct and validate a nomogram prediction model for the early identification of such patients， and to provide a basis for early clinical prevention and management. MethodsA retrospective analysis was performed for the clinical data of 1 822 patients with PHC in two medical institutions from January 2019 to June 2025， among whom the 1 518 patients from The Third People’s Hospital of Kunming were used as the training set to construct the nomogram prediction model， and the 304 patients from The Second People’s Hospital of Baoshan were used as the validation set. According to the result of high-sensitivity cardiac troponin T measurement before intervention， the patients with PHC were divided into myocardial injury group and non-myocardial injury group. The univariate analysis， the LASSO regression analysis， and the multivariate Logistic regression analysis were used to identify the risk factors of concurrent myocardial injury in PHC patients before intervention， and then a nomogram prediction model was constructed based on these findings. The independent data of the 304 patients in the validation set were used for external validation， and the area under the receiver operating characteristic curve （AUC）， the Hosmer-Lemeshow test， the calibration curve， decision curve analysis， and clinical impact curve were used to assess model performance. ResultsIn the training set， there were 346 patients in the myocardial injury group and 1 172 patients in the non-myocardial injury group， and the prevalence rate of concurrent myocardial injury was 22.79%. The mean age was 56.44±9.45 years， and the male patients accounted for 81.49%. The patients with drinking， smoking， chronic hepatitis B， chronic hepatitis C， hypertension， diabetes， Child-Pugh class A liver disease， BCLC stage B liver disease， or abnormal electrocardiographic findings accounted for 49.34%， 57.44%， 61.73%， 32.48%， 22.66%， 17.19%， 50.53%， 33.86%， and 62.12%， respectively. The univariate analysis， the LASSO regression analysis， and the multivariate Logistic regression analysis showed that age （odds ratio ［OR］=1.051， 95% confidence interval ［CI］： 1.036 — 1.067， P<0.001）， history of diabetes （OR=1.862， 95%CI： 1.346 — 2.574， P<0.001）， electrocardiographic findings （OR=1.446， 95%CI： 1.077 — 1.940， P=0.014）， hemoglobin （HGB） （OR=0.993， 95%CI： 0.988 — 0.998， P=0.003）， albumin （Alb） （OR=0.951， 95%CI： 0.930 — 0.972， P<0.001）， and creatinine （Cr） （OR=1.021， 95%CI： 1.016 — 1.026， P<0.001） were independent influencing factors for myocardial injury in PHC patients. A regression equation was established as Logit（Y）=-3.406+0.050×age+0.621×history of diabetes+0.369×electrocardiogram－0.007×HGB－0.051×Alb+0.021×Cr， and a nomogram prediction model was constructed based on these factors. The Bootstrap internal validation of the model yielded an AUC of 0.743 （95%CI： 0.707 — 0.778）， and the model had an AUC of 0.766 （95%CI： 0.738 — 0.794） in the training set and 0.730 （95%CI： 0.688 — 0.793） in the validation set. The Hosmer-Lemeshow goodness-of-fit test yielded a P value of 0.716 for the training set and 0.408 for the validation set， suggesting that the model had a good degree of fitting. Calibration curves， decision curve analysis， and clinical impact curves in both the training set and the validation set showed that the model had a good clinical application value. ConclusionAge， history of diabetes， electrocardiographic findings， HGB， Alb， and Cr are independent influencing factors for myocardial injury in patients with PHC， and the nomogram prediction model constructed based on these factors has good discriminatory ability， accuracy， and clinical practicability.

Guanylate binding protein subunit β-2(GNB2)is an important part of G protein family.In the process of cell signal transduction,GNB2 plays a structural support and regulatory role in G protein complex,ensuring the correct transmission and amplification of signals,interacting with receptors and regulating vari-ous effector enzymes and ion channels,and mediating a variety of physiological functions.Therefore,GNB2 plays a key role in cell signaling,and participates in the regulation of cell proliferation,differentiation and mi-gration and other biological processes.This article reviews the research progress of GNB2,focusing on its structure,function,regulatory mechanism,disease correlation and importance in tumor research.

Currently,there are practical and technical difficulties in the construction of clinical ques-tions in the development of clinical practice guidelines.Clinicians or guideline developers seldom construct clin-ical questions based the actual case scenario,leading to some information loss between structured and actual clinical connotation.To overcome this challenge,we proposed a case-guided questions construction approach,and carried out case research and verification in the formulation of the guideline.We found that this method could more efficiently and scientifically assist the formulation of clinical questions,and provide reference for clinicians or guideline developers.

Objective:To evaluate the cumulative live birth rate (CLBR) and cost-effectiveness of fixed versus adjusted follicle-stimulation hormone (FSH) dosages in infertile women with different ovarian responses during their first assisted reproductive technology (ART) cycle.Methods:A retrospective real-world cohort study was conducted on 5 419 infertile women who underwent their first ART treatment at the Department of Reproductive Medicine of the First Affiliated Hospital of Nanjing Medical University between January 2013 and December 2017. All patients received an individualized starting dosage of gonadotropin. Based on whether FSH dosages were adjusted during controlled ovarian stimulation (COS), patients were divided into fixed-dosage group ( n=2 061) and adjusted-dosage group ( n=3 358). Clinical outcomes and FSH cost-effectiveness were compared between the two groups across different ovarian response groups, with CLBR as the primary outcome. Propensity score matching (PSM) and multivariable logistic regression were used to adjust for potential confounders. Results:FSH dosage adjustments were found in 62.0% (3 358/5 419) of cycles during COS. After PSM, baseline characteristics were comparable between the two groups (all P>0.05). After adjusting for confounders using multivariable logistic regression, FSH dosage adjustment was not significantly associated with CLBR ( OR=1.06, 95% CI: 0.94-1.20, P=0.332). Compared with the adjusted-dosage group, the fixed-dosage group showed no significant differences in CLBR in poor-, normal-, and high-responder groups (all P>0.05). The incidence of ovarian hyperstimulation syndrome (OHSS) did not differ significantly between the two groups ( P>0.05). In poor-, normal-, and high-responder groups, the total FSH dosages in the fixed-dose group [1 350 (375, 1 825) U, 1 200 (375, 1 500) U and 525 (375, 1 128) U, respectively] were significantly lower than those in the adjusted-dose group [1 875 (1 425, 2 294) U, P=0.001; 1 425 (450, 1 875) U, P<0.001; 600 (375, 1 425) U, P=0.020]. Similarly, average FSH costs in different ovarian response groups in the fixed-dosage group [4 725.0 (1 312.5, 6 387.5) yuan, 4 200.0 (1 312.5, 5 250.0) yuan and 1 837.5 (1 312.5, 3 947.3) yuan, respectively] were significantly lower than those in the adjusted-dosage group [6 562.5 (4 987.5, 8 028.1) yuan, P=0.001; 4 987.5 (1 575.0, 6 562.5) yuan, P<0.001; 2 100.0 (1 312.5, 4 987.5) yuan, P=0.020]. For normal-responders, the FSH cost per high-quality embryo in the fixed-dosage group [1 365.0 (875.0, 2 537.5) yuan] was significantly lower than that in the adjusted-dosage group [2 056.3 (1 268.8, 3 412.5) yuan, P<0.001]. Conclusion:FSH dosage adjustment during COS is not associated with CLBR or the incidence of OHSS. However, the fixed-dose group exhibited lower total FSH dosages and costs across different ovarian response populations. In the context of ART being covered by medical insurance, fixed FSH dosage may represent a more cost-effective ovarian stimulation protocol.

With the extended survival period of breast cancer patients and the increasing health demands, the concomitant diseases of breast cancer have gradually attracted the attention of both doctors and patients, and it is imperative to conduct comprehensive management of these diseases, in which the general practitioners, as the more comprehensive and complex medical talents, have not yet played their due roles. In this article, we report two cases of comprehensive management of concomitant diseases of breast cancer through collaboration of general practitioners and specialists (integrated general and specialist care). The role and function of general practitioners in this process were deeply analyzed, and the establishment of a consultation-liaison general practice model to further promote the role of integrated general and specialist care in integrated oncology care was advocated.

With the improvement of diagnosis and treatment level, most breast cancer patients survive in a chronic state for a long time, and the issue of concomitant diseases of breast cancer (CDBC) has become increasingly prominent. All-round and full-cycle management of these comorbidities can help improve patients’ quality of life and prognosis. General practice, with its long-term, comprehensive and responsible health care that is person-centered, family-based, community-wide and oriented to the maintenance and promotion of overall health, presents new opportunities for the health management of CDBC. This article will explore the application of consultation-liaison general practice through the integrated general and specialist care in the comprehensive management of CDBC, aiming to raise people’s awareness of it and promote the development of consultation-liaison general practice and the management model of the "Internet plus general practitioner team" , which will surely contribute to the all-round management of concomitant diseases in breast cancer patients.

Objective:To investigate the situation of computed tomography(CT)equipment and socio economic development of various grades and classifications of medical institutions in Jiangsu Province,and to analyze the interrelationship between them.Methods:From October 20,2023 to November 20,2023,a questionnaire survey was conducted on imported and domestic CT equipment of various grades and classifications of medical institutions in 13 prefecture-level cities in Jiangsu Province through online questionnaire survey of"questionnaire star".The gross domestic product(GDP)of each prefecture-level city in Jiangsu province was used as an indicator of measuring the level of socio-economic development in the region.The CT number,the row number of detector,quality of image,the total examination case number of daily average and the daily average case number of single machine examination of medical institutions of various grades and classifications of 13 prefecture-level cities were used to conduct correlation analysis with GDP values of various districts.Results:A total of 910 questionnaires were distributed,and 512 questionnaires were retrieved.There were 482 valid questionnaires in the 512 questionnaires,and the valid rate was 94.15,which involved to 482 various grade and classification institutions of 13 prefecture-level cities in Jiangsu province.The number of imported and domestic CT equipment in the 13 prefecture-level cities of Jiangsu Province positively correlated with the GDP of each city(r=0.882,0.880,P<0.001).The number of imported CT equipment with 64 rows and more than 64 rows,and with less than 64 rows,and the number of domestic CT equipment with 64 rows and more than 64 rows,and with less than 64 rows all positively correlated with the GDP of each city(r=0.880,0.881,0.736,0.897,P<0.05).The total number of daily average of examinations for imported and domestic CT equipment of 13 prefecture-level cities positively correlated with the GDP of each city(r=0.774,0.814,P<0.05).There were no significant difference in the image quality and the daily average case number of single machine examination between the domestic CT equipment and the imported CT equipment(P>0.05).Conclusion:The medical institutions of city with high level of economic development have more quantitative and more high-end CT equipment,and the quality of image of domestic CT equipment is equal to that of imported CT equipment regardless of the high and low level of economic development.

At present,indocyanine green(ICG)is intraoperative imaging agent with the most of advantages,and the ICG fluorescence imaging technique that derived from it has been widely developed in surgery with laparoscope for colorectal cancer.This technique can effectively realize tumor localization,assessment for resection margin,imaging of lymph node and lymphatic vessel,which has important value in judging the blood supply of the anastomosis,and can further effectively improve surgical safety and reduce the risk of postoperative complications.In addition,ICG fluorescence imaging technique can also powerfully promote the development of minimally invasion and individualization of colorectal surgery.With the advancement of laparoscopic equipment,deepening of medical theory,progress of surgical techniques,and the integration of artificial intelligence and medicine,the application scenarios of ICG imaging technique are gradually expanding.This article reviewed the imaging principles,current status of application,and current existing issues of ICG fluorescence imaging technique in surgery for colorectal cancer,which conducted preliminarily exploration for its value in guiding the practice of the theory of membrane anatomy.