Haixia Zhang

Purpose: To characterize the spatiotemporal evolution of corneal biomechanical properties after corneal cross-linking (CXL) using optical coherence elastography (OCE), with particular emphasis on regional changes in a hemicorneal partial-CXL model and temporal responses to standard and accelerated CXL (ACXL). Methods: A silicone corneal phantom was constructed for system validation. Seven New Zealand white rabbits underwent hemicorneal partial-CXL in both eyes to investigate regional biomechanical changes. In addition, 11 rabbits received standard CXL or ACXL in contralateral eyes. OCE measurements were performed before and after treatment, and Corvis ST was additionally performed for complementary biomechanical assessment. Results: OCE identified spatial biomechanical heterogeneity and quantified regional and temporal changes after CXL. In the hemicorneal partial-CXL model, linear mixed-effects analysis demonstrated a significant region-by-time interaction ( P < 0.001). The OCE-derived elastic modulus in the treated region was significantly higher than that in the untreated region at all postoperative time points ( P < 0.001). Compared with baseline, the treated region increased by 38.6%, 31.1%, and 56.8% at 1 week, 2 weeks, and 1 month, respectively, while the untreated region remained stable. The elastic modulus exhibited a temporal remodeling pattern characterized by an early increase, a mild decline at the intermediate stage, and a subsequent increase. Standard CXL and ACXL showed similar time-dependent biomechanical changes, with no significant differences between protocols at corresponding postoperative time points. Conclusion: OCE revealed spatial heterogeneity and dynamic remodeling of corneal biomechanics after CXL. These findings support OCE as a tool for spatially resolved and longitudinal evaluation of CXL-induced biomechanical changes and provide a basis for future personalized CXL strategies.

Non-alcoholic fatty liver disease (NAFLD) specifically includes the stage of simple fatty liver and the stage of hepatitis. Recent research found mesenchymal stem cell therapy for NAFLD. Mesenchymal stem cells regulate metabolic pathways and energy transport pathways in disease models, reducing the synthesis and utilisation of glucose and fatty acids and restoring the homeostasis of the internal microenvironment. For areas with more severe damage, umbilical cord mesenchymal stem cells (UCMSC) are used for regenerative repair with classic Wnt pathway. The text explores the therapeutic effects of UCMSCs on hepatitis and the surrounding environment from a multifunctional perspective. Mesenchymal stem cells release exosomes in a paracrine manner into the damaged areas of the liver, promoting the differentiation and development of hepatic progenitor cells into hepatocytes, reducing differentiation into cholangiocytes, while assisting hepatic progenitor cells in resisting the progression of inflammation and fibrosis, and promoting the normal function of adaptive immune responses.

To enhance the science and engineering literacy of undergraduate students in medical and pharmaceutical programs and support the cultivation of innovative medical talents, this paper takes the third batch of national first-class undergraduate courses offered offline at Capital Medical University, “Medical Physics,” as an example to systematically explore its course construction and implementation pathways, with the hope of providing references for similar course construction. The course adheres to the construction philosophy of “student-centered, outcome-oriented, and diversified integration and innovation.” The construction measures include: content integration emphasizing the guidance of curriculum ideology and politics to promote the integration of medicine and engineering; resource construction focusing on building a smart course and virtual simulation experimental system based on knowledge graphs; evaluation reform implementing a combination of process assessment and formative evaluation; and the implementation of blended teaching exploration relying on rich course resources and smart course platforms. Practice has shown that the course has effectively improved students’ science and engineering literacy and comprehensive abilities and has received positive learning feedback. Through systematic construction, the course has achieved an organic unity of knowledge transmission, ability cultivation, and value shaping, providing replicable experience for the construction of science and engineering quality education courses in medical and pharmaceutical programs.

Coronary artery aneurysms (CAA) pose significant clinical risks of thrombosis and ischemia, yet the geometric determinants beyond aneurysm size remain poorly defined, making their understanding essential for improving early diagnosis and tailored interventions. We analyzed serial coronary computed tomography angiography data from 80 CAA patients with two serial scans, classifying them into the non-thrombus group and the thrombus group based on the final scan. All CAA morphological characteristics were quantified and compared between groups. Computational fluid dynamics simulations were performed to extract hemodynamic parameters, including wall shear stress (WSS) and vortex flow (Q-criterion), for a comparative inter-group analysis. An integrated analysis of morphological and hemodynamic data was conducted to identify determinants of thrombosis. Among all geometric variables, cross-sectional eccentricity (CE) was the only parameter showing significant baseline differences (P < 0.001). Lower CE values (higher eccentricity) were associated with adverse shear conditions and pronounced near-wall vortex coverage, characterized by prominent “neckerchief”-shaped vortices on the CAA. Regression analyses showed CE alone explained 33%–40% of the variance in these disturbed flow regions. Near-wall vortex correlated with low-WSS regions. Spatial and temporal relationships indicated that CE and vortex consistently predicted sites of subsequent thrombus deposition. This study identifies CE as a critical noninvasive predictor of thrombus. CE promotes thrombus formation in CAA by creating a pro-thrombotic environment characterized by “neckerchief”-shaped vortices at the aneurysm neck. These findings clarify the geometry–hemodynamics–thrombosis relationship and provide key evidence for early clinical assessment of thrombotic risk in CAA.

Medical physics is one of the integrated science and engineering education courses for medical students, and the ideological and political construction of the course is crucial for cultivating innovative medical talents. In order to explore the paths and methods to achieve the goal of cultivating virtue and nurturing people through course ideological and political education, this paper deeply discusses the systematic teaching design of digital empowerment of course ideological and political cases based on the background of educational digital transformation. The design covers the extraction of course ideological and political elements, the development of course ideological and political cases, the construction of carriers for course ideological and political cases, and the exploration of teaching methods for course ideological and political education. Taking the “discovery of X-ray crystal diffraction phenomenon” as a specific example, it details how to effectively integrate course ideological and political cases into teaching practice. This teaching design can provide strong support for the organic combination of ideological and political education with professional knowledge, promote the synchronous improvement of students' knowledge, ability and quality, and cultivate innovative talents in the “new medical science”.

To develop a method to fabricate early keratoconus phantom models and evaluate the feasibility of using corneal models for studying the dynamic response of early keratoconus under an air puff. A corneal mold was designed, and the silicone material was poured into the mold to produce corneal phantoms. Two types of early keratoconus phantoms with reduced mechanical properties in a specific area were prepared using a two-step molding process: the central keratoconus phantom and the paracentral keratoconus phantom. Corneal Visualization Scheimpflug Technology tonometry was performed on the normal corneal phantoms and early keratoconus phantoms, and the corresponding dynamic corneal response (DCR) parameters were recorded. A majority of DCR parameters of the normal corneal phantoms, including deflection amplitude at highest concavity (HCDA), peak distance (PD), radius of curvature (HR), first and second applanation times (A1T and A2T), first and second applanation velocities (A1V and A2V), and the stiffness parameter at the first applanation (SPA1), exhibited trends in response to changes in the simulated intraocular pressure (SIOP) that aligned with experimental results based on ex vivo animal eyes. Significant differences in HCDA, PD, HR, A1V, A2V, A1T, A2T, and integrated radius (IR) were observed between the early keratoconus phantoms and the normal corneal phantoms. The early keratoconus phantom models fabricated by the present novel approach are feasible for studying the dynamic response of early keratoconus under an air puff. This study demonstrated the potential of corneal phantom models for corneal biomechanical studies, which can deepen our understanding of the DCR parameters, and the results will provide valuable information for early diagnosis of keratoconus.

Purpose: To analyze the influence of dextran solution and corneal collagen crosslinking (CXL) on corneal biomechanical parameters in vitro, evaluated by Corneal Visualization Scheimpflug Technology (Corvis ST). Materials and Methods: Forty porcine eyes were included in this study. Twenty porcine eyes were instilled with dextran solution for 30 min (10 eyes in 2% dextran solution and 10 eyes in 20% dextran solution). CXL treatment was performed in 10 porcine eyes; the other 10 porcine eyes were regarded as the control group. Each eye was fixed on an experimental inflation platform to carry out Corvis measurements at different IOPs. Corneal biomechanical parameters were calculated based on Corvis measurement. Statistical analysis was used to analyze the influence of dextran solution and CXL on corneal biomechanical parameters based on Corvis parameters. Results: The corneal energy-absorbed area (A_absorbed) decreased after being instilled with dextran solution under IOP of 15 mmHg (p < 0.001); the elastic modulus (E) of the cornea instilled with 20% dextran solution was significantly higher than that instilled with 2% dextran solution (p < 0.001), since it decreased after being instilled with 20% dextran solution (p = 0.030); the stiffness parameter at the first applanation (SP-A1) increased after CXL (p < 0.001). Conclusions: Both dextran solution and CXL can change corneal biomechanical properties; the concentration of dextran solution can influence the corneal biomechanical properties, which may, in turn, affect the effectiveness of CXL. SP-A1 may be used as an effective parameter for the evaluation of CXL.