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.

BACKGROUND:It has been found that abnormal apoptosis of bone tissue cells induced by abnormal iron metabolism plays an important role in the progression of osteoporosis. OBJECTIVE:To investigate the effect of naringin on iron metabolism and cell apoptosis in bone tissue of rats with osteoporosis. METHODS:Fifty 2-month-old female Sprague-Dawley rats were randomly divided into five groups with 10 rats in each group:sham group,osteoporosis group,naringin low-dose group,naringin high-dose group,and naringin high-dose+DKK-1 group.Except for the sham group,rat models of osteoporosis were established by removing bilateral ovarian tissues in the other groups.At 8 weeks after modeling,rats in the naringin low-and high-dose groups were given 100 and 400 mg/kg/d naringenin by gavage,respectively,and rats in the naringenin high dose+DKK-1 group were given 400 mg/kg/d naringin by gavage and subcutaneous injection of 25 mg/kg/d DKK-1,an inhibitor of the Wnt1 signaling pathway,for 7 consecutive days.Relevant indexes were detected after administration. RESULTS AND CONCLUSION:Compared with the osteoporosis group,naringin could enhance the bone mineral density and serum calcium and superoxide dismutase levels in rats(P<0.05),and reduce the serum levels of osteocalcin,malondialdehyde,and phosphorus(P<0.05),while DKK-1 could partially inhibit the interventional effect of naringin(P<0.05).Results from Micro-CT scanning,hematoxylin-eosin and TUNEL staining showed that compared with the osteoporosis group,naringin significantly improved bone microstructure and reduced the rate of cell apoptosis,while DKK-1 partially inhibited the interventional effect of naringin.Immunofluorescence staining results showed that compared with the osteoporosis group,naringin could reduce the oxygen content,anti-tartaric acid phosphatase expression,and elevate the expression of alkaline phosphatase in active tibia tissues(P<0.05),while DKK-1 could partially inhibit the interventional effect of naringin(P<0.05).Results from Prussian blue staining and immunohistochemical staining showed that compared with the osteoporosis group,naringin reduced iron deposition in bone and liver tissues as well as the expression of transferrin receptor 1(P<0.05),and elevated the protein expression of ferroportin 1(P<0.05)in bone tissue,and DKK-1 partially inhibited the intervention of naringin(P<0.05).PCR and western blot assay of tibia specimens showed that compared with the osteoporosis group,naringin decreased the expression of anti-tartrate acid phosphatase,transferrin receptor 1 and Bax(P<0.05),and elevated the expression of alkaline phosphatase,ferroportin 1,Bcl-2,Wnt1 and β-catenin(P<0.05),while DKK-1 partially inhibited the interfering effect of naringin(P<0.05).To conclude,naringin inhibits the progression of osteoporosis by reducing iron deposition and apoptosis rate in bone tissue,which may be related to the activation of the Wnt1 signaling pathway.

Objective:To investigate the current status and risk factors of central venous catheter-related thrombus（CRT）in critically ill children，and to provide evidence for proposing preventive measures.Methods:This study was a single-center cross-sectional survey.The hospitalized children with central venous catheters implanted in the intensive care unit of Shanghai Children's Medical Center,Shanghai Jiao Tong University School of Medicine from January to March 2024 were included.Based on the ultrasound diagnosis indicating CRT or the presence of visually detectable thrombi after central venous catheter removal,the children included in the study were categorized into the CRT group and the non-CRT group.The data of demographic，clinical data，laboratory tests，medication treatment，and catheter related information of the affected children were collected.Univariate and multivariate analyses were performed to identify risk factors associated with CRT.Results:A total of 328 children were included，of which 158 cases（48.2%）were female，with the median age of 35.00（9.00，88.75）months.There were 51 cases（15.6%）in CRT group and 277 cases（84.4%）in non-CRT group.After adjusted by pediatric critical illness score，multivariate binary Logistic analysis revealed that the use of normal saline for catheter flushing and sealing (adjust OR=26.52,95% CI 8.32-84.60, P<0.001),longer duration of vasoactive drug use (adjust OR=5.06,95% CI 1.93-13.26, P=0.001),higher Caprini scale score (adjust OR=3.09,95% CI 1.38-6.91, P=0.006),presence of high-risk comorbidities or complications (adjust OR=2.87,95% CI 1.11-7.45, P=0.030),longer immobilization time (adjust OR=1.13,95% CI 1.07-1.19, P<0.001),and lower international normalized ratio after catheter placement (adjust OR=0.10,95% CI 0.02-0.53, P=0.007) were independent risk factors affecting the occurrence of CRT. Conclusion:The incidence of CRT is relatively high among critically ill children,and medical staff can develop targeted intervention measures by taking relevant risk factors into consideration.

Guided by Zhang Zhongjing's axiom that"blood stasis induces water",this study develops stage-specific treatment strategies for edema in Kidney Consumption Disorder by examining its four-stage pathogenic progression:Sluggish Flow → Stagnant Obstruction → Depressed Accumulation → Stasis Congelation.We propose an integrated approach that reinforces the root by warming the kidney and replenishing essence,while addressing the branch by activating blood circulation and promoting diuresis.Stage-specific interventions include:for the Sluggish Flow Phase,warming and tonifying kidney Yang combined with unblocking Yang to promote uri-nation;for the Stagnant Obstruction Phase,warming the kidney and replenishing essence supported by activating blood circulation and freeing the collateral channels;for the Depressed Accumulation Phase,quickening blood and resolving stasis,regulating Qi and trans-forming turbidity,along with warming the kidney and strengthening essence;and for the Stasis Congelation Phase,expelling stagnant accumulations while simultaneously regulating essence and blood.This framework advances novel pattern-determined strategies for Kid-ney Consumption edema management.

Objective To explore the clinical efficacy of percutaneous ureteral flexible ureteral holmium laser lithotripsy(PNHLL)and single ureteral flexible percutaneous nephrolithotomy(ECIRS)in the treatment of complex kidney stones.Methods The clinical data of 103 patients with complex renal calculi admitted to our hospital from January 2015 to March 2023 were retrospectively analyzed.According to the surgical methods,they were divided into PNHLL group(53 cases)and ECIRS group(50 cases).The perioperative related indicators,stone clearance rate,renal function,stress response and postoperative complications were compared between the two groups.Results The operation time of ECIRS group was longer than that of PNHLL group[(97.62±19.52)min vs.(72.43±14.48)min],and the success rate of stone removal was higher than that of PNHLL group[92.00％(46/50)vs.75.47％(40/53)](P＜0.05).After operation,the levels of blood urea nitrogen(BUN)[(15.44±3.08)mmol/L vs.(17.21±3.44)mmol/L],cystatin C(CysC)[(611.85±34.22)μg/L vs(637.42±35.41)μg/L],creatinine(Scr)[(77.52±8.64)μmol/L vs.(81.63±9.07)μmol/L],superoxide dismutase(SOD)[(108.64±7.24)U/ml vs.(115.27±7.68)U/ml],prostaglandin E2(PGE2)[(162.41±18.05)μmol/L vs.(175.48±19.47)μmol/L],nitric oxide(NO)[(74.61±8.29)μmol/L vs.(78.58±8.73)μmol/L]and cortisol(Cor)[(188.64±29.02)nmol/L vs.(212.42±32.68)nmol/L]in ECIRS group were lower than those in PNHLL group(P＜0.05).Conclusion Compared with PNHLL,ECIRS has a higher success rate of stone clearance in the treatment of complex renal calculi,and has less renal function and postoperative traumatic stress response,which is beneficial to postoperative recovery.

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.

Pressure ulcer is a common complication of long-term bed rest in intensive care unit(ICU)patients,which can increase the risk of infection and prolong ICU hospitalization.They are an important indicator of patient safety and nursing quality in medical institutions.Early prevention of pressure ulcer is an important means of controlling their development.At present,the prevention of pressure ulcer mainly involves timed flipping and the use of pressure reducing devices.However,during the flipping process,it often requires two or more nursing staff to complete,which increases the workload and also exacerbates the occurrence of occupational lower back pain among nursing staff.In addition,existing pressure reducing devices still have certain limitations in use,and their functions are single,often requiring the combination of multiple tools to increase material and financial resources.Based on this,the research team from the department of critical care medicine of Hospital of Chengdu University of Traditional Chinese Medicine,has designed a nursing device for preventing pressure ulcer in critically ill patients,and has obtained a National Utility Model Patent of China(Patent Number:ZL 202320609787.6).It has several inflation components and connecting structures.The inflation components are equipped with a connected air inlet,a connected air outlet,and a discharge port on the side;the inflatable components are fitted together and can be detachably connected through a connecting structure.The connected air inlet of one inflatable component corresponds to the connected air outlet of adjacent inflatable components.This device is connected by multiple inflation components,which lower or raise the height of the airbag through inflation and deflation,adjust the pressure on various parts of the patient's body,and solve the problem of labor-intensive and heavy workload in nursing work;In addition,multiple inflatable components can be detachably connected to form an inflatable mattress.When in use,the number of inflatable component connections can be selected according to the specific needs of different patients or nursing areas.The device is easy to operate,flexible in combination,and suitable for timed flipping pressure reduction regulation in pressure ulcer high-risk areas under various postures.It has good clinical application value.