ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.

In recent years,emerging evidence has revealed the non-classical biological functions of platelets.Research on the regulation of platelet bioenergetic metabolism and its functional implications is of great significance for understanding the mecha-nisms of related diseases and developing novel therapeutic strate-gies.Current research is focusing on platelet-derived mitochon-dria because of their distinct biological characteristics.Notably,the ability of platelets to transfer mitochondria to recipient cells can reprogram the metabolism and function of these cells,poten-tially playing a pivotal role in diverse pathophysiological proces-ses.This review comprehensively summarizes the emerging roles of platelet-derived mitochondria transfer in various diseases in-cluding diabetes mellitus,cardiovascular disorders,neurodegen-erative diseases,and cancer.It further explores the application prospects in these diseases,providing a scientific basis for the development of precise therapeutic strategies.

Objective:To investigate the risk factors for adverse outcomes in elderly patients with nonvalvular atrial fibrilla-tion(AF)after percutaneous left atrial appendage closure(LAAC)combined with radiofrequency ablation(RFA).Meth-ods:A total of 199 elderly AF patients who admitted in Department of Cardiology,Yuhuangding Hospital between Jan 1st,2019 and Aug 17th,2023 and underwent LAAC combined RFA were enrolled.The patients were divided into case group(n=78)and control group(n=121)according to presence of atrial arrhythmia and/or cerebral infarction(CI)within one year after operation.Baseline clinical data,laboratory indexes and color Doppler ultrasound indexes were compared be-tween the two groups,and multivariate Logistic regression was used to analyze the risk factors for postoperative atrial ar-rhythmia and/or CI.Receiver operating characteristic(ROC)curve was constructed to analyze the predictive efficacy of risk factors for atrial arrhythmia and/or CI after operation.Results:Univariate analysis indicated that compared with pa-tients in control group,those in case group had significant higher proportions of preoperative persistent atrial fibrillation(52.60％ vs.37.20％),old myocardial infarction(OMI)(11.50％vs.1.70％)and left atrial diameter(LAD)[(45.47±6.90)mm vs.(43.34±6.64)mm](P＜0.05 or＜0.01).Multivariate Logistic regression analysis indicated history of OMI(OR=8.736,95％CI 1.772～43.069,P=0.008)and LAD(OR=1.053,95％CI 1.006～1.102,P=0.027)were independent risk factors of adverse outcomes in elderly AF patients after LAAC+RFA.ROC analysis indicated that predic-tive efficacy of combined detection of OMI and LAD(AUC=0.663,95％CI 0.593～0.728)for adverse outcomes within 1 year in elderly AF patients after LAAC+RFA was significantly better than those of OMI(AUC=0.549,95％CI 0.477～0.620)and LAD(AUC=0.602,95％CI 0.531～0.671)alone(Z=3.045,2.312,P=0.002,0.021).Conclusion:His-tory of old myocardial infarction and left atrial diameter are independent risk factors for atrial arrhythmia and/or cerebral infarction within 1 year after percutaneous left atrial appendage closure combined with radiofrequency ablation in elderly patients with atrial fibrillation,and the combination has good predictive performance.

Objective:To investigate the risk factors for adverse outcomes in elderly patients with nonvalvular atrial fibrilla-tion(AF)after percutaneous left atrial appendage closure(LAAC)combined with radiofrequency ablation(RFA).Meth-ods:A total of 199 elderly AF patients who admitted in Department of Cardiology,Yuhuangding Hospital between Jan 1st,2019 and Aug 17th,2023 and underwent LAAC combined RFA were enrolled.The patients were divided into case group(n=78)and control group(n=121)according to presence of atrial arrhythmia and/or cerebral infarction(CI)within one year after operation.Baseline clinical data,laboratory indexes and color Doppler ultrasound indexes were compared be-tween the two groups,and multivariate Logistic regression was used to analyze the risk factors for postoperative atrial ar-rhythmia and/or CI.Receiver operating characteristic(ROC)curve was constructed to analyze the predictive efficacy of risk factors for atrial arrhythmia and/or CI after operation.Results:Univariate analysis indicated that compared with pa-tients in control group,those in case group had significant higher proportions of preoperative persistent atrial fibrillation(52.60％ vs.37.20％),old myocardial infarction(OMI)(11.50％vs.1.70％)and left atrial diameter(LAD)[(45.47±6.90)mm vs.(43.34±6.64)mm](P＜0.05 or＜0.01).Multivariate Logistic regression analysis indicated history of OMI(OR=8.736,95％CI 1.772～43.069,P=0.008)and LAD(OR=1.053,95％CI 1.006～1.102,P=0.027)were independent risk factors of adverse outcomes in elderly AF patients after LAAC+RFA.ROC analysis indicated that predic-tive efficacy of combined detection of OMI and LAD(AUC=0.663,95％CI 0.593～0.728)for adverse outcomes within 1 year in elderly AF patients after LAAC+RFA was significantly better than those of OMI(AUC=0.549,95％CI 0.477～0.620)and LAD(AUC=0.602,95％CI 0.531～0.671)alone(Z=3.045,2.312,P=0.002,0.021).Conclusion:His-tory of old myocardial infarction and left atrial diameter are independent risk factors for atrial arrhythmia and/or cerebral infarction within 1 year after percutaneous left atrial appendage closure combined with radiofrequency ablation in elderly patients with atrial fibrillation,and the combination has good predictive performance.

Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P＜0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P＞0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.

Fetal ultrasound standard plane detection was introduced in terms of its importance and problems encountered.The deep learning techniques applied in fetal standard plane detection were reviewed,including transfer learning,modified basic network,hybrid network and multi-task network.The problems encountered by the deep learning techniques during the application were analyzed,and the future research directions were envisioned.[Chinese Medical Equipment Journal,2025,46(5):91-101]

In recent years,emerging evidence has revealed the non-classical biological functions of platelets.Research on the regulation of platelet bioenergetic metabolism and its functional implications is of great significance for understanding the mecha-nisms of related diseases and developing novel therapeutic strate-gies.Current research is focusing on platelet-derived mitochon-dria because of their distinct biological characteristics.Notably,the ability of platelets to transfer mitochondria to recipient cells can reprogram the metabolism and function of these cells,poten-tially playing a pivotal role in diverse pathophysiological proces-ses.This review comprehensively summarizes the emerging roles of platelet-derived mitochondria transfer in various diseases in-cluding diabetes mellitus,cardiovascular disorders,neurodegen-erative diseases,and cancer.It further explores the application prospects in these diseases,providing a scientific basis for the development of precise therapeutic strategies.

To screen potential drugs for the treatment of acute Liver Injury(ALI)through network pharmacology and mitochondrial dynamics,and to investigate their actions and mechanisms.Based on the commonly utilized Liver Pure Tablets and Liver-Protecting Capsules in the market,a com-ponent library of liver disease drugs was screened and established.Pharmacological anchoring anal-ysis was carried out.Potential liver disease therapeutic drugs were screened out through molecular docking,and feedback verification was performed using animal experiments.Acute liver injury mouse models were established through excessive induction with acetaminophen(APAP),and the histopathological changes of liver tissues were examined.The protective effect of the drug on ALI was evaluated by detecting alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),catalase(CAT),glutathione(GSH),and malondialdehyde(MDA)using enzyme-linked immunosorbent assay(ELISA).qRT-PCR was employed to detect peroxi-some proliferator-activated receptor gamma coactivator 1-alpha(PPARG1A),mitofusin 1(MFN1),mitofusin 2(MFN2),dynamin-related protein 1(DRP1),optic atrophy 1 protein(OP A1),Steroid receptor coactivator(SRC),and advanced glycosylation end-product specific re-ceptor(AGER)to explore the protective mechanism of the drug on ALI.The result showed that Network pharmacology identified a total of 662 intersection targets of three types of prescription drugs and ALI.Eventually,72 core targets were screened out.Pathway enrichment analysis indi-cates that the potential mechanism might be associated with the lipid and atherosclerosis signaling pathways.The results of the relevant molecular docking indicate that the most likely optimal drug might be emodin(EMO).EMO ameliorated the pathological damage in mice with acute liver inju-ry,significantly decreased the contents of transferase factors ALT and AST,simultaneously in-creased the contents of antioxidant enzymes CAT,GSH and SOD,and reduced the content of oxi-dative metabolic end product MDA.It also upregulated the mRNA expression levels of MFN1、MFN2,OPA1,DRP1,SRC and PPARGC1A proteins in liver tissue,and inhibited the mRNA ex-pression level of AGER protein.The drug EMO,jointly screened out by network pharmacology through anchoring and molecular docking,might promote mitochondrial fusion metabolism,allevi-ate liver oxidative stress,and improve liver injury in ALI mice via the Lipid and atherosclerosis pathway.

Objective:To explore the application of the flipped classroom teaching method in pediatric internship, evaluate the feedback from both students and faculty, and provide evidence for optimizing clinical medical education strategies.Methods:Fourth-year students ( n=174) enrolled in 2019 in the eight-year clinical medicine program at Peking University Health Science Center and instructors ( n=42) participated in this study. Questionnaire survey and exit examination scores were used to assess the effectiveness of the flipped classroom method. A statistical analysis was performed using SPSS 26.0. Kruskal-Wallis test and Dunn's multiple comparisons were used to evaluate the differences in satisfaction across teaching components. Chi-square test and Fisher's exact test were applied to compare satisfaction between high-score (top 30%) and low-score (bottom 30%) student groups. Results:①Overall student satisfaction with the flipped classroom reached 91.33% ("very satisfied" + "satisfied"). High satisfaction was reported for pre-class self-learning videos (80.35%), recommended clinical guidelines (82.80%), and English literature (71.10%), while satisfaction with the flipped classroom lectures was comparatively low (52.60%), with significant differences compared to other components ( P<0.05). ②High-score students exhibited significantly lower satisfaction than low-score students across all components (overall evaluation, 84.61% vs. 98.08%, Fisher's exact test, P=0.031; pre-class videos, 53.85% vs. 76.92%, χ2=6.12, P=0.013; preparatory assignments, 61.54% vs. 80.77%, χ2=4.68, P=0.030; English literature, 53.85% vs. 75.00%, χ2=5.80, P=0.016; and flipped class lectures, 36.54% vs. 59.62%, χ2=5.55, P=0.019). ③Enhanced competency in ≥2 core areas was reported in 71.68% of students, including theoretical knowledge acquisition (49.71%), self-directed learning (35.84%), clinical thinking (31.21%), research capabilities (25.43%), and communication skills (22.54%). ④Faculty feedback indicated that 83.33% of instructors perceived the flipped classroom as equivalent or superior to traditional teaching, particularly in cultivating clinical thinking (90.48%), self-directed learning (85.71%), theoretical knowledge acquisition (76.19%), and communication skills (76.19%). ⑤Student participation willingness was primarily influenced by pre-class time investment (46.51% reported excessive effort in preparing discussion materials), while faculty engagement depended on implementation effectiveness (42.86%) and curriculum design (35.71%). Conclusions:The flipped classroom method demonstrated promising initial outcomes in pediatric internship, with high satisfaction among both students and faculty. However, further exploration and practice are required in optimizing teaching components, implementing differentiated instructional strategies, and managing time investment.

Fetal ultrasound standard plane detection was introduced in terms of its importance and problems encountered.The deep learning techniques applied in fetal standard plane detection were reviewed,including transfer learning,modified basic network,hybrid network and multi-task network.The problems encountered by the deep learning techniques during the application were analyzed,and the future research directions were envisioned.[Chinese Medical Equipment Journal,2025,46(5):91-101]