A natural experiment is a causal inference study design grounded in real-world research. Its core concept is to use quasi-random variation in exposure generated by external factors to evaluate the effects of interventions or exposures on outcomes. It is particularly suitable for research settings in which randomized controlled trials （RCTs） are infeasible or ethically constrained， and it combines causal inference capacity with relatively strong external validity. This article provides an overview of the definition， key features， and current application status of natural experiments， and proposes the application scenarios for applying natural experiment strategies to the evaluation of therapeutic effects in traditional Chinese medicine （TCM）， including policy implementation or policy change evaluation， assessment of variations in clinical practice within hospitals， and evaluation of differences in resource allocation across regions or institutions. The design pathway includes starting from clinical or policy-related TCM questions， systematically collecting relevant data， performing statistical modeling and effect estimation， and interpreting effect estimates in the context of clinical practice. It further analyzes the advantages and challenges of using natural experiments in TCM.

A natural experiment is a causal inference study design grounded in real-world research. Its core concept is to use quasi-random variation in exposure generated by external factors to evaluate the effects of interventions or exposures on outcomes. It is particularly suitable for research settings in which randomized controlled trials （RCTs） are infeasible or ethically constrained， and it combines causal inference capacity with relatively strong external validity. This article provides an overview of the definition， key features， and current application status of natural experiments， and proposes the application scenarios for applying natural experiment strategies to the evaluation of therapeutic effects in traditional Chinese medicine （TCM）， including policy implementation or policy change evaluation， assessment of variations in clinical practice within hospitals， and evaluation of differences in resource allocation across regions or institutions. The design pathway includes starting from clinical or policy-related TCM questions， systematically collecting relevant data， performing statistical modeling and effect estimation， and interpreting effect estimates in the context of clinical practice. It further analyzes the advantages and challenges of using natural experiments in TCM.

OBJECTIVE: Exploring the formation and aggregation of human islet amyloid polypeptide (hIAPP) (amylin) fibers is significant for promoting the prevention and treatment of type II diabetes mellitus (T2DM). Flavones in pomelo peel have visible biological activity in the anti-diabetes aspect. The present study aimed to investigate the effects of five flavones [naringin (NRG), narirutin (NRR), nobiletin (NOB), sinensetin (SIN), and neohesperidin (NHP)] in pomelo peel on peptide aggregation and explore its possible mechanisms. The cell viability of flavones against peptide aggregation was also evaluated. METHODS: The thioflavin T (ThT) assay and transmission electron microscopy (TEM) were used for evaluating the inhibition and disaggregation of flavones on peptide aggregation. The interaction mechanism was analyzed by endogenous fluorescence, molecular dynamics (MD) simulations, ultraviolet spectroscopy (UV) and isothermal titration calorimetry (ITC) experiments. The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and immune assays were performed to characterize the cell viability of flavones against peptide aggregation. RESULTS: The five flavones showed a decrease in fluorescence intensity, fiber number and size under incubation with different molar ratios of hIAPP. The compounds can bind to the aromatic tyrosine (Tyr) residueTyr 37, resulting in the intrinsic fluorescence quenching of the peptides. Five flavones can form hydrogen bonds with hIAPP, which is likely to be based on their phenolic hydroxyl structure. They showed strong binding affinity with peptides. The reaction system of NRG and NRR observed an exothermic reaction, and the others were endothermic reactions. The absorption peaks of the compounds with hIAPP changed and showed hypochromic effects, indicating that there may be π-π stacking interaction. Flavones noticeably increased the cell viability in the presence of amyloid peptides and reduced the absorption intensity induced by peptide oligomers. CONCLUSION A total of five flavones in pomelo peel have inhibitory and depolymerization effects on amyloid fibrils, and can significantly protect cells from the toxic effect of hIAPP and reduce the production of toxic oligomers.

Objective:To explore the efficacy of different second-line treatment strategies in the real world after progression of first-line immunotherapy and its combination therapies in patients with driver gene-negative advanced non-small cell lung cancer (NSCLC) .Methods:A retrospective analysis was conducted on the clinical data of 93 driver gene-negative advanced NSCLC patients who received first-line immunotherapy and its combination therapies from January 1, 2018 to December 31, 2023 at the First Affiliated Hospital of Xinxiang Medical University and Xinxiang Central Hospital. Patients were categorized into immune checkpoint inhibitors (ICIs) -resistant ( n=43) and ICIs-responsive ( n=50) groups according to whether progression free survival (PFS) exceeded 6 months after first-line treatment. Patients were categorized into ICIs-treated ( n=55) and non-ICIs-treated ( n=38), anti-angiogenic-treated ( n=51) and non-anti-angiogenic-treated ( n=42) groups according to the different second-line treatment strategies after progression of first-line immunotherapy and its combination therapies. The median PFS2 (mPFS2) and median overall survival (mOS) 2 after second-line treatment of each group were compared. The Kaplan-Meier method was used for survival analysis. Results:The mPFS2 and mOS2 of 93 advanced NSCLC patients who progressed after first-line ICIs treatment were 4.9 months (95% CI: 4.1-5.7 months) and 14.7 months (95% CI: 11.2-18.2 months). The mPFS2 of patients in the first-line ICIs-responsive and ICIs-resistant groups were 6.0 and 3.8 months, respectively, with no statistically significant difference ( χ2=2.00, P=0.157), and the mOS2 were 25.3 and 11.3 months, respectively, with a statistically significant difference ( χ2=12.13, P<0.001). The mPFS2 of patients in the second-line ICIs-treated group and the non-ICIs-treated group were 5.2 and 4.6 months, respectively, with no statistically significant difference ( χ2=0.16, P=0.687). The mOS2 were 15.1 and 12.7 months, respectively, with no statistically significant difference ( χ2=0.01, P=0.930). The mPFS2 of patients in the second-line anti-angiogenic-treated and non-anti-angiogenic-treated groups were 4.5 and 6.0 months, respectively, with no statistically significant difference ( χ2=0.41, P=0.525), the mOS2 were 14.7 and 16.8 months, respectively, with no statistically significant difference ( χ2=0.01, P=0.943) . Conclusions:After progression of first-line ICIs therapy in patients with driver gene-negative advanced NSCLC, first-line ICIs-responsive patients have significantly longer OS after second-line treatment compared with ICIs-resistant patients. The efficacy of second-line therapy in patients after progression of first-line ICIs therapy does not show significant differences due to the type of treatment strategies.

Objective:To investigate the safety and efficacy of the artery-first approach pancreaticoduo-denectomy (PD) combined with portal vein/superior mesenteric vein (PV/SMV) resection and reconstruction for pancreatic head malignancies.Methods:A retrospective analysis was conducted on 322 patients who underwent PD with PV/SMV resection and reconstruction at the Hepatobiliary Pancreatic Surgery Department of the First Hospital Affiliated to Naval Medical University between January 2016 and December 2022. Patients were divided into the artery-first approach PD group (AFA-PD group, n=165) and standard PD group (SPD group, n=157) based on surgical approach. Baseline characteristics, surgical outcomes, postoperative outcomes, pathological results and survival data were compared between two groups. Results:Compared to the SPD group, the AFA-PD group exhibited significantly reduced intraoperative blood loss (500 ml vs 600 ml), lower rates of obvious intraoperative blood loss (≥1 000 ml: 25.45% vs 40.13%), and decreased transfusion requirements (26.67% vs 52.87%). Postoperatively, the AFA-PD group demonstrated lower incidence of grade B/C pancreatic fistula (10.30% vs 19.75%) and higher textbook outcome achievement (78.79% vs 66.24%). Pathologically, the AFA-PD group achieved superior lymph node yield (20 nodes vs 18 nodes) and higher R 0 resection rates (79.39% vs 64.33%), particularly at the posterior pancreatic margin (96.97% vs 91.72%, P=0.040), SMA margin (92.07% vs 82.17%), and SMV margin (88.48% vs 78.98%). Multivariate logistic regression identified arterial invasion >180°, venous invasion >180°, lymph node metastasis, and the artery-first approach as independent predictors of R 0 resection. The AFA-PD group showed prolonged median survival (19.17 month vs 15.73 month). All aforementioned differences were statistically significant (all P value <0.05). Conclusions:The artery-first approach PD combined with PV/SMV resection and reconstruction is safe and effective for pancreatic head malignancies, significantly improving R 0 resection rates and patients' survival outcomes.

Objective:To evaluate the safety and clinical efficacy of enteral nutrition (EN) initiated within 24 h after heart transplantation in pediatric patients.Methods:A retrospective cohort study was conducted. Clinical data from 16 pediatric heart transplant recipients at the Seventh Medical Center of the Chinese People′s Liberation Army General Hospital between October 2022 and October 2024 were collected, including demographics, anthropometric measurements, biochemical markers, cytokine levels, and clinical outcomes. Based on the timing of EN initiation, the patients were divided into EN-initiated within 24 h and EN-initiated after 24 h 2 groups. Demographic data, preoperative extracorporeal membrane oxygenation (ECMO) support, physical examination indicators, laboratory parameters, and cytokine levels were compared between groups using independent samples t-test, Mann-Whitney U test, Fisher′s exact probability test. Results:The cohort comprised 16 patients (10 males and 6 females) with an age of (12.5±1.9) years. The EN-initiated within 24 h group comprised 6 cases, and the EN-initiated after 24 h group comprised 10 cases. No significant difference was observed between the two groups in age, preoperative body mass index Z-score, preoperative ECMO support, physical examination indicators, laboratory parameters (total protein, albumin, hemoglobin), or cytokine levels (all P>0.05). Compared to the EN-initiated after 24 h group, the EN-initiated within 24 h group exhibited a shorter intensive care unit stay ( t=2.65, P<0.05) and shorter mechanical ventilation duration ( t=2.23, P<0.05) than EN-initiated after 24 h group. Total hospitalization length had no significant difference ( P>0.05). At 72 h post-transplant, the EN-initiated within 24 h group had a lower interleukin-12 P70 ( t=2.46, P<0.05) and interferon-γ levels ( t=2.55, P<0.05) than EN-initiated after 24 h group. Prior to discharge, the EN-initiated within 24 h group has a lower mean skinfold thickness ( t=2.49, P<0.05) and lower mid-upper arm circumference ( t=2.36, P<0.05) compared with the EN-initiated after 24 h group. Conclusions:Initiating EN within 24 h postoperatively is safe and feasible in pediatric heart transplant recipients. Early EN may shorten the length of intensive care unit stay and mechanical ventilation while attenuating postoperative release of inflammatory cytokine.

Objective:To analyze the influencing factors of China′s DRG payment system reform(DRG reform) and its hierarchical relationship, for references for the in-depth promotion of China′s medical insurance payment reform.Methods:Relevant literature on DRG reform in China from databases such as CNKI, Wanfang Database, Pubmed, etc, were obtained. Content analysis method was used to extract the influencing factors of DRG reform. The correlation between each influencing factor was determined through expert discussion. An interpretive structural model(ISM) was constructed to analyze the hierarchical relationship of factors influencing DRG reform.Results:After analysis, the influencing factors(12) of DRG reform in China were included such as medical level, hospital management, and medical staff′s cognition and behavior. Among them, the local situation was the deep-level factor affecting DRG reform, 9 factors such as data quality assurance and policy design/implementation were the middle-level factors, and patients′ interests/needs and disease grouping were the surface-level factors.Conclusions:There were many influencing factors on the reform of China′s DRG payment system. It was suggested that relevant management departments in various regions should focus on the actual situation of the locality, take data quality and policy design and implementation as the key points of reform, formulate a scientific and reasonable DRG grouping scheme, safeguard the interests of patients, so as to promote the deepening of DRG reform.

Follicular lymphoma(FL)is a type of non-Hodgkin's lymphoma,and its treatment options face many challenges.This paper discusses the pathogenesis and treatment of FL based on the clear-turbid theory in traditional Chinese medicine(TCM)."The clear and the turbid being related,and the rise and fall of qi being disorderly"is the basic pathogenesis of FL.As the disease progres-ses,"evil qi being blocked inside,and turbid evil harming the clear"aggravates,and finally"evil qi is strong and the disease progres-ses,and evil poison is generated inside".Based on this theory,the method of raising the clear and lowering the turbid and the method of dispersing the clear and removing the turbid are proposed to treat FL.The emphasis of raising the clear and lowering the turbid is to take raising and lowering as the key,movement and stillness as the pivot,and to treat the middle jiao;the emphasis of dispersing the clear and removing the turbid is to clear the triple jiao,warm the yang and invigorate the qi,and harmonize the spleen and kidney.Ca-ses are attached to illustrate,providing new ideas for the TCM treatment of FL.

Objective:To understand the status and influencing factors of social isolation in elderly individuals with chronic diseases.Methods:A multi-stage sampling method was used to select elderly individuals from eight communities or villages in Hefei from July to September 2022. The study employed a general information survey, the Lubben Social Network Scale (LSNS-6) , the Geriatric Depression Scale (GDS-15) , the Social Support Rating Scale (SSRS) , and the Personal Social Capital Scale 16 (PSCS-16) . Binary Logistic regression analysis was used to explore the factors influencing social isolation in elderly individuals with chronic diseases.Results:A total of 1 133 elderly individuals were surveyed, among which 538 had chronic diseases. Among the 538 elderly individuals with chronic diseases, 209 were socially isolated, resulting in a social isolation rate of 38.8%. Binary Logistic regression analysis revealed that living area, fear of falling, depression, social capital, and social support were significant factors influencing social isolation ( P<0.05) . Conclusions:The social isolation rate among elderly individuals with chronic diseases is high. Special attention should be given to elderly individuals living in rural areas, those who fear falling, and those experiencing depression. Additionally, improving social capital and social support can help alleviate social isolation in these elderly individuals.

Objective:To verify the prognostic value of perineural invasion and lymphovascular tumor embolus for patients with gastric cancer undergoing gastrectomy and postoperative chemotherapy, and establish a prognostic prediction nomogram model.Methods:According to 7∶3 radio, 781 gastric cancer patients were randomly divided into training cohort and internal validation cohort. One hundred fifty patients were utilized as the external validation cohort. Univariate and multivariate analysis were performed to evaluate the prognostic value of perineural invasion and lymphovascular tumor embolus, and construct the dynamic nomogram. The concordance index (C-index), net reclassification index and integrated discrimination improvement index, receiver operating characteristic curve, calibration curves and decision curve analysis were used to evaluate the nomogram.Results:Perineural invasion ( HR=1.486, 95% CI: 1.150-1.919, P<0.01) and lymphovascular tumor embolus ( HR=1.321, 95% CI: 1.030-1.693, P<0.05) were independent prognostic risk factors for patients with gastric cancer after gastrectomy and postoperative chemotherapy. C-index (training cohort: 0.734, internal validation cohort: 0.755, external validation cohort: 0.715), net reclassification index (training cohort: 0.228 for 3-year and 0.213 for 5-year OS prediction; internal validation cohort: 0.211 for 3-year and 0.279 for 5-year OS prediction; external validation cohort: 0.220 for 3-year and 0.440 for 5-year OS prediction) and integrated discrimination improvement index (training cohort: 0.051 for 3-year and 0.041 for 5-year OS prediction; internal validation cohort: 0.027 for 3-year and 0.036 for 5-year OS prediction; external validation cohort: 0.063 for 3-year and 0.153 for 5-year OS prediction) indicated that the nomogram performed better than the traditional TNM staging system ( P<0.05). Conclusions:Perineural invasion and lymphovascular tumor embolus are independent prognostic risk factors of gastric cancer patients after postoperative chemotherapy. The novel dynamic nomogram model based on perineural invasion and lymphovascular tumor embolus provides better assistance in evaluating prognosis of gastric cancer patients.