Objective: This study investigates the association between myeloperoxidase (MPO) levels and anxiety risk in Chinese adults and explores potential effect modifiers, with implications for neuroinflammatory biomarker-guided anxiety prevention strategies.Methods: Using cross-sectional data from 30,418 adults undergoing routine health examinations (July 2020–June 2021), anxiety severity was assessed via the Self-Rating Anxiety Scale (SAS; score ≥ 50 as clinically relevant). Plasma MPO was quantified by ELISA. Multivariate logistic regression, restricted cubic splines (RCS), threshold effect analysis, and subgroup interactions were conducted to evaluate nonlinear associations.Results: A U-shaped relationship between MPO and anxiety risk was identified. In fully adjusted models, participants in the lowest (Q1: ≤29.77 ng/mL, OR = 1.15, 95% CI: 1.03–1.28, p = 0.01) and highest quintiles (Q5: ≥47.3 ng/mL, OR = 1.17, 95% CI: 1.05–1.31, p = 0.004) exhibited significantly elevated anxiety risks compared to the reference quintile (Q2: 29.8–34.7 ng/mL). RCS analysis confirmed a nonlinear association (p for nonlinearity < 0.01), with an inflection point at 30 ng/mL: below this threshold, each 1 ng/mL MPO increase reduced anxiety risk (OR = 0.982, CI: 0.970–0.994), while levels above it heightened risk (OR = 1.004, CI: 1.001–1.008). Diabetes mellitus significantly modified this relationship (p-interaction = 0.028), with diabetic individuals showing amplified risks at higher plasma MPO (Q5 OR = 1.84 vs. non-diabetic Q5 OR = 1.15).Conclusion: Plasma MPO demonstrates a U-shaped association with anxiety risk independent of cardiometabolic confounders. Diabetic individuals exhibit heightened susceptibility to MPO-related anxiety, suggesting synergistic neuroinflammatory pathways. Monitoring MPO may aid in risk stratification and personalized interventions, particularly in populations with diabetes.

Background: Myeloperoxidase (MPO) is a key enzyme involved in immune responses and oxidative stress, yet its roles in gastric physiology and gastric cancer remain incompletely understood. This study comprises two independent analyses: (1) to investigate the association between MPO and gastric mucosal injury markers (pepsinogen I, II, and PGR) in a large healthy population, and (2) to evaluate the prognostic significance and immune-regulatory mechanisms of MPO in gastric adenocarcinoma (GA).Methods: We analyzed data from 16,943 individuals in a healthy population-based cohort and 375 GA patients from The Cancer Genome Atlas (TCGA). In the healthy cohort, multivariate linear regression was used to evaluate associations between MPO and pepsinogen levels. In the GA cohort, survival analyses (OS, DSS, PFI) were conducted using Kaplan-Meier and Cox regression models. Gene expression analysis, functional enrichment (GO, KEGG, GSEA), and immune infiltration analysis (ssGSEA) were performed to explore MPO-related mechanisms in GA.Results: In the healthy cohort, MPO was inversely associated with PGR (β = -0.009, P < 0.0001) and PGI (β = -0.057, P < 0.0001). Subgroup and threshold effect analyses revealed non-linear associations and stronger effects among hypertensive individuals, smokers, and alcohol consumers. In the TCGA cohort, high MPO expression was an independent predictor of poor OS (HR = 2.781, P = 0.002) and DSS (HR = 3.667, P < 0.001). Functional analyses showed that MPO was associated with immune-related pathways and increased infiltration of macrophages (R = 0.379, P < 0.001) and dendritic cells (R = 0.377, P < 0.001).Conclusion: This study highlights the distinct roles of MPO in gastric mucosal injury and gastric cancer. In healthy individuals, MPO is associated with markers of gastric mucosal damage, while in GA patients, MPO serves as a prognostic biomarker linked to immune dysregulation. These findings suggest that MPO may be a potential target for monitoring or intervention in gastric mucosal injury and gastric cancer.

BACKGROUND: Critical thinking is a core goal of medical education, underpinning clinical decision-making and scientific innovation. This study evaluates the current status of the disposition toward critical thinking among postgraduate medical students who intend to pursue careers in clinical practice, research, or public health leadership, and identifies factors associated with its variability. METHODS: Using convenience and snowball sampling, we conducted a cross-sectional survey using the Short-Form Critical Thinking Disposition Inventory-Chinese Version (SF-CTDI-CV). Participants were medical postgraduate students from 16 universities in China, including Sichuan University, Chongqing Medical University and so on. Univariate analyses and multivariable linear regression with stepwise selection were carried to evaluate associations between SF-CTDI-CV scores and demographics, academic engagement, and training exposures. RESULTS: The mean SF-CTDI-CV score was 81.8 (SD = 11.44; possible range: 18-108), indicating a generally positive disposition among the participants. Multiple regression analysis revealed that several factors significantly influence critical thinking disposition, including extracurricular reading time, academic ranking, papers read in depth per week, working hours, pre-enrollment background, participation in innovation and entrepreneurship competitions, attendance at academic conferences, Only-child status and frequency of research presentations (model R ² = 0.102). Subgroup comparisons indicated that students who are only children, have professional or research experience, and possess a science background tend to achieve higher scores in critical thinking disposition assessments. CONCLUSIONS: In this study, the Chinese SF-CTDI-CV was used to measure critical thinking disposition. The mean score of 82 (out of 108) indicates a generally positive disposition toward critical thinking among participants. Extracurricular reading time, academic ranking, and research engagement (including papers read, conference attendance, and research presentations) were independently associated with disposition scores. These findings suggest that educational strategies promoting deep reading, research involvement, and academic discussion may help foster critical thinking disposition in postgraduate medical education.

Objectives: This study investigates the nonlinear association between myeloperoxidase (MPO) levels and Helicobacter pylori (H. pylori) infection risk in Chinese adults, evaluating potential modifiers and clinical implications for infection prevention. Methods: An analysis was conducted on cross-sectional data from 15,180 adults who underwent routine health examinations between January and December 2021. H. pylori infection was diagnosed using the 14C-urea breath test with a threshold of disintegrations per minute (DPM) ≥ 100. ELISA was used to measure plasma MPO levels. Nonlinear associations were assessed through logistic regression, restricted cubic splines, threshold effect analysis, and subgroup interactions. Results: The study identified a U-shaped correlation between MPO levels and the risk of H. pylori infection. Compared to the middle tertile (T2: 20.6–31 ng/mL), participants in the lowest (T1: ≤20.6 ng/mL; OR = 1.36, 95% CI: 1.24–1.49) and highest tertiles (T3: ≥31 ng/mL; OR = 1.12, 1.02–1.22) exhibited elevated infection risk after full adjustment (p < 0.001). DPM levels were notably elevated in T1 (β = 37.1, 26.66–47.57) and T3 (β = 19.27, 8.81–29.72) relative to T2 (p < 0.0001). RCS-based threshold analysis identified a nonlinear inflection at 24.0 ng/mL of MPO, where each additional 1 ng/mL of MPO below this threshold was associated with a reduced infection risk (OR = 0.959, 95% CI: 0.947–0.971), whereas levels above increased the risk (OR = 1.004, 95% CI: 1.002–1.007). This pattern aligned with H. pylori breath test values, which mirrored the U-shaped trend across MPO tertiles. Subgroup analyses revealed uniform associations between MPO and H. pylori infection risk/DPM across various factors such as age, sex, BMI, and metabolic comorbidities, with all interaction p-values exceeding 0.05. Conclusions: MPO levels exhibit a robust U-shaped association with H. pylori infection risk, independent of anthropometric and metabolic confounders. Monitoring MPO may aid in identifying individuals at bidirectional infection risk, suggesting novel insights into the inflammation–infection interplay. The study’s cross-sectional design limits the ability to establish causal relationships, necessitating further longitudinal research to validate these findings and elucidate their clinical implications.