1.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
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.
2.The Regulatory Effects and Mechanisms of Piezo1 Channel on Chondrocytes and Bone Metabolic Dysregulation in Osteoarthritis
Yan LI ; Tao LIU ; Yu-Biao GU ; Hui-Qing TIAN ; Lei ZHANG ; Bi-Hui BAI ; Zhi-Jun HE ; Wen CHEN ; Jin-Peng LI ; Fei LI
Progress in Biochemistry and Biophysics 2026;53(3):564-576
Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca2+, K+, and Na+, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca2+ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca2+ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca2+ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.
3.Association of dietary patterns with overweight and obesity among children and adolescents based on latent class analysis
CHEN Hongyuan, ZHANG Wen, LI Ziye, MA Yueyan, GUL Maham, ZHOU Jin, MA Fuchang
Chinese Journal of School Health 2026;47(6):883-887
Objective:
To analyze the characteristics of latent classes of dietary patterns among children and adolescents in Qinghai Province, and their association with overweight and obesity, so as to provide a scientific basis for conducting targeted nutritional interventions and weight management for the local population.
Methods:
From May to October 2025, a multi stage stratified cluster random sampling method was employed to recruit 1 611 children and adolescents aged 6-17 years from Chengdong District of Xining City and Gonghe County of Hainan Tibetan Autonomous Prefecture in Qinghai Province. Questionnaire survey was conducted using a questionnaire developed by the Chinese Center for Disease Control and Prevention, and physical examination was conducted by using unified measurement standards. Latent class analysis (LCA) was performed on the food intake frequency of the participants. The χ 2 test and Logistic regression analysis were applied to explore the relationship between dietary patterns and overweight/obesity.
Results:
The detection rates of overweight, obesity, and overall overweight/obesity among the participants were 10.4%, 5.8%, and 16.2%, respectively. Latent class analysis identified three dietary patterns: modern mixed pattern ( n =399, 24.8%), low diversity pattern ( n =476, 29.5%), and traditional dietary pattern ( n =736, 45.7%). The potential category distribution differences of three dietary patterns among children and adolescents with and without overweight or obesity were statistically significant (non overweight and obesity: 22.5%, 29.1%, 48.4%; overweight and obesity: 36.4%, 31.8%, 31.8%) ( χ 2=30.69, P <0.01). Logistic regression showed that, compared with the traditional dietary pattern, the modern mixed pattern was associated with a higher risk of overweight and obesity ( OR =1.68, 95% CI =1.13-2.49); female sex was associated with a lower risk of overweight/obesity compared with male sex ( OR =0.66, 95% CI =0.50-0.86) (both P <0.05).
Conclusions
A positive association exists between the modern mixed dietary pattern and obesity in children and adolescents. It is recommended to reduce the intake of grains and unhealthy foods among overweight and obese children and adolescents, while increasing the consumption of legumes, fish, and shrimp, in order to cultivate healthy and rational dietary habits.
4.Association between working hours and occupational stress among employees in manufacturing enterprises
WAN Jialu ; JIN Wen ; RUAN Xiaoying ; YU Jiamian ; CHEN Jiarui
Journal of Preventive Medicine 2025;37(8):837-841
Objective:
To understand the relationship between working hours and occupational stress among front-line employees in manufacturing enterprises, so as to provide a basis for the prevention and control of occupational stress.
Methods:
Front-line employees from 5 manufacturing enterprises in Hangzhou City were selected from June to November 2024 using random cluster sampling. Demographic information and occupational information such as daily average working hours and weekly working hours, were collected through questionnaires. The effort-reward imbalance questionnaire was used to investigate occupational stress. The association between working hours and occupational stress was analyzed using a multivariable logistic regression model.
Results:
A total of 926 people were surveyed, among whom 572 were male, accounting for 61.77%, and 354 were female, accounting for 38.23%. The average age was (32.98±8.28) years. There were 515 people (55.62%) who had a monthly personal income of more than 5 000 yuan but less than 9 000 yuan. There were 353 people (38.12%) who had a working seniority of less than 5 years. There were 784 people (84.67%) who had an average daily working hours of >8 hours and 645 people (69.65%) who had a weekly working day of more than 5 days. There were 338 people (36.50%) on the shift work system, and 331 people (35.75%) worked night shifts. A total of 707 people were detected with occupational stress, with a detection rate of 76.35%. Multivariable logistic regression analysis showed that after adjusting for gender, age, educational level, marital status, number of children, only-child status, monthly personal income, working seniority, weekly working hours, assembly-line work, shift work system and night shift, compared with employees with an average daily working hours of ≤8 hours, the risk of occupational stress increased by 118.7% for those with an average daily working hours of >8-<10 hours (OR=2.187, 95%CI: 1.434-3.336) and by 248.4% for those with an average daily working hours of ≥10 hours (OR=3.484, 95%CI: 2.034-5.966).
Conclusions
The detection rate of occupational stress among front-line employees in manufacturing enterprises in Hangzhou City is high. Long average daily working hours can increase the risk of occupational stress among employees in manufacturing enterprises. It is recommended to reasonably arrange work intensity and working hours.
5.Diagnostic value of mediastinal lymph nodes CT imaging features in pulmonary sarcoidosis
Yuehong LI ; Ting RUAN ; Kun WEN ; Ying CHEN ; Yantian LYU ; Minghua JIN ; Li XU ; Guopeng XU
Chongqing Medicine 2025;54(1):168-171
Objective To explore the diagnostic value of mediastinal lymph nodes CT image features in pulmonary sarcoidosis.Methods The imageologic data of the patients with pulmonary sarcoidosis(pulmonary sarcoidosis group)and lung cancer complicating mediastinal lymph node metastasis(lung cancer group)con-firmed by EBUS-TBNA in this hospital from June 2015 to November 2023 were analyzed retrospectively.The chest plain scan CT and enhanced scan CT were performed in all cases,and the imaging characteristics were compared between the two groups.The receiver operating characteristic(ROC)curve was drawn and the area under the curve(AUC)was calculated.The diagnostic value of CT imaging characteristics in pulmonary sar-coidosis was analyzed.Results The proportion of female patients in the lung sarcoidosis group was signifi-cantly higher than that in the lung cancer group,while the age was smaller than that in the lung cancer group,and the differences were statistically significant(P<0.05).The number of mediastinal lymph nodes,location,short diameter and CT enhancement value in the pulmonary sarcoidosis group had statistical difference(P<0.05).The ROC curve analysis showed that AUC of lymph node short diameter reciprocal,CT enhancement value and position in detection alone were 0.586,0.785 and 0.505 respectively,and AUC of the three combined reciprocal was the highest(0.789).Conclusion The lymph node short diameter,CT enhancement value and po-sition have certain value in clinical diagnosis of pulmonary sarcoidosis and the 3-indicator combination could increase the diagnostic efficiency of pulmonary sarcoidosis.
6.Advances of Metal-Organic Framework Stationary Phases for Gas Chromatographic Separations
Yan JIN ; Wen-Bo LI ; Yu-Chen ZHU ; Bin ZHAO ; Lei LI ; Dan ZHENG ; Fei FENG
Chinese Journal of Analytical Chemistry 2025;53(1):1-13
Metal-organic frameworks(MOFs)are porous materials composed of metal ions or metal clusters and organic ligands by coordination,which have the advantages of large specific surface area,good thermal stability and adjustable pore size,and have a promising application in gas chromatographic separation.In recent years,MOFs materials have been used as stationary phases for gas chromatography mainly including ZIF,MIL,UiO-66,HKUST-1,IRMOFs,etc.Based on the molecular sieve effect,van der Waals forces,hydrogen bonding and π-π interactions,the pore size,pore microenvironment,unsaturated metal site and special functional group of the MOFs stationary phase materials can be specifically designed and regulated.MOFs materials as stationary phases have unique separation performance for n-alkanes and their isomers,aromatic compounds and their isomers,alcohols/ketones/aldehydes and their isomers,and chiral compounds.The combination of organic polymers and novel nanomaterials with MOFs materials can improve the separation performance and stability of MOFs.Therefore,MOFs materials are expected to be the promising stationary phase that can be applied to gas separation in complex environments.In this article,the research advances of various stationary phases based on MOFs for gas chromatography in recent years were reviewed.The separation performance and separation mechanism of MOFs stationary phases for mixed gas samples were discussed,and the development trends in the future were prospected.
7.Preparation and Performance Test of Highly Stable Ammonium Ion Selective Electrode Based on Hydrophobic Solid Contact Layer
Chen-Yu LIU ; Jia-Wen YIN ; Yun-Zhe HAN ; Sheng-Kang LU ; Qing-Hui JIN
Chinese Journal of Analytical Chemistry 2025;53(5):774-784
The stability of ammonium ion selective electrode is an important indicator to ensure accurate monitoring of ammonia nitrogen concentration in drinking water.However,in long-term monitoring process,interfering ions and water molecules in water samples may penetrate into the interior of the ammonium ion selective electrode to form a water layer,which affects the potential response and stability of the electrode.Perfluorooctanoic acid is a low surface energy material,and doping it in polyaniline can reduce surface energy of the composite and improve surface roughness.In this work,five ammonium ion selective electrodes were prepared by doping polyaniline with different concentrations of perfluorooctanoic acid as a solid contact layer,which made the solid contact layer of electrode had hydrophobic properties,thereby improving stability of the ammonium ion selective electrode.The stability of the ion-selective electrode was evaluated by potential drift experiment,and the optimal doping concentration of perfluorooctanoic acid in the sediment solution was determined to be 5 mmol/L.The experiment results showed that the solid contact layer had a water contact angle of 132o under the doping concentration,the potential drift rate was 41.66 μV/h,and potential drift rate in the aqueous layer test was 1.31 mV/h,which were all better than those of the unmodified electrode.The standard deviation of the electrode potential was 1.42 mV,which was obviously superior to that of the unmodified electrode.The characteristics of high stability of the electrode made it suitable for long-term monitoring of ammonia nitrogen content in water samples.
8.Toxicokinetics of Chlorfenapyr and Its Metabolites in Rats
Wen-Yan LI ; Jin-Feng ZHAO ; Wei-Chen LIU ; Shi-Jing LÜ ; Jia-Xin ZHANG ; Xu-Dong ZHANG ; Zhi-Wen WEI ; Ke-Ming YUN ; Chao ZHANG
Journal of Forensic Medicine 2025;41(4):380-386
Objective To establish a chromatography-tandem mass spectrometry method for detecting chlorfenapyr and its metabolite tralopyril in blood,and to investigate the toxicokinetics in rats.Methods Chlorfenapyr(8 mg/kg)was administered orally to rats,and blood samples were collected from rats'canthus vein at 5 min,15 min,30 min,1 h,3 h,6 h,12 h,24 h and 48 h after administration.The blood samples were extracted using 100 μL of 5%formic acid solution and 400 μL of acetonitrile.Chlorfena-pyr was qualitatively and quantitatively detected by triple quadrupole gas chromatography-tandem mass spectrometry(GC-MS/MS)and tralopyril was detected by triple quadrupole liquid chromatography-tandem mass spectrometry(LC-MS/MS).The DAS 3.0 software was used to fit the toxicokinetic equa-tions and calculate the toxicokinetic parameters.Results Chlorfenapyr was detectable from 5 min to 24 h with a peak time of 1 h.Tralopyril was detectable from 15 min to 48 h with a peak time of 3 h.The toxicokinetic process of chlorfenapyr in rat blood conformed to a first-order absorption one-compartment open model,with the toxicokinetic equation described as C=e-0.265t-e-0.175t.Tralopyril con-formed to the first-order absorption three-compartment model,and the toxicokinetic equation was C=47 361.069e-2.209t-35 404.962e-1.486t+11 956.363e-0.512t.In the equations,C stands for the concentration of the target substance in the blood,e is the natural constant(≈2.718 28),and t stands for time.Conclu-sion This study optimized the detection method for chlorfenapyr and its metabolite tralopyril in blood.The toxicokinetic equations and parameters of chlorfenapyr and tralopyril can provide a reference for the estimation of oral intake time of chlorfenapyr.
9.Risk Factors and Prognosis of Pneumoconiosis Combined With Bacterial Pneumonia:Application of a Random Forest Model
Qiaolan WANG ; Linshen XIE ; Wen DU ; Menglin CHEN ; Rujia YOU ; Qiaoling JIN
Journal of Sichuan University (Medical Sciences) 2025;56(4):1076-1082
Objective To apply a random forest model combined with logistic regression in the understudied area of pneumoconiosis complications,and to investigate the incidence and risk factors of pneumoconiosis complicated by bacterial pneumonia,and the effect of concomitant bacterial pneumonia on the survival and prognosis of patients with pneumoconiosis.Methods Pneumoconiosis patients admitted to the West China Fourth Hospital,Sichuan University,between January 2018 and April 2022 were enrolled and divided into a group of those with only pneumoconiosis and another group of those with pneumoconiosis complicated by bacterial pneumonia.Univariate analyses,including chi-squared test,t-test,or rank sum test,were conducted to examine the differences between the groups.A random forest model was used to screen the variables,and the risk factors of pneumoconiosis complicated by bacterial pneumonia were identified by stepwise forward logistic regression method.Cox regression was applied to the survival data to assess the effect of concomitant bacterial pneumonia on the survival and prognosis of pneumoconiosis patients.Results Among the 742 pneumoconiosis patients,536 cases(72.24%)had concomitant bacterial pneumonia.Among the 55 deaths,36 cases(65.45%)had concomitant bacterial pneumonia.Univariate analysis showed statistically significant differences in age,duration of disease,lung function,duration of exposure,lung lavage,pulmonary tuberculosis,and emphysema between the two groups(P<0.05).The variables were screened using the random forest model,and the risk factors were ranked in a descending order of their importance—the types of dust,duration of exposure,lung function,lung lavage,and pulmonary tuberculosis.After screening,multivariate logistic regression analysis showed that the types of dust(compared with silica dust,silicate dust:odd ratio[OR]=8.100,95%CI,1.386-47.331;carbon dust:OR=1.728,95%CI,1.034-2.887;artificial inorganic dust:OR=2.138,95%CI,1.146-3.988),impaired lung function(compared with undamaged lung function group,the group of patients with mild,moderate,and moderately severe damage:OR=2.292,95%CI,1.482-3.544),and pulmonary tuberculosis(OR=1.559,95%CI,1.071-2.271)were risk factors for pneumoconiosis complicated by bacterial pneumonia.The median follow-up was 30.0 months,ranging from 1.0 month to 64.0 months.Cox regression analysis showed that the mortality risk for pneumoconiosis patients with concomitant bacterial pneumonia was 2.369 times higher than that for patients without bacterial pneumonia(95%CI,1.286-4.367).Conclusion Pneumoconiosis patients are susceptible to bacterial pneumonia and are influenced by multiple risk factors.Concomitant bacterial pneumonia markedly affects the patient prognosis.
10.Exosomes derived from bone marrow mesenchymal stem cells alleviate hypoxia/reoxygenation-induced cardiomyocyte injury
Wen WEN ; Chenxi LIU ; Shuangjing CHEN ; Xiaojiong LU ; Zhitao JIN ; Zheng ZHANG
Basic & Clinical Medicine 2025;45(12):1557-1564
Objective To explore the effects and mechanisms of bone marrow mesenchymal stem cell(BMMSC)-derived exosomes(BMMSC-Exo)on hypoxia/reoxygenation(H/R)-induced injury in rat cardiomyocyte cell line(H9c2).Methods BMMSC-Exosomes were isolated by ultracentrifugation.The cells were divided into three groups:control,H/R,and H/R+BMMSC-Exo(H/R+Exo).A hypoxia/reoxygenation(H/R)injury model was es-tablished by exposing cells to 12 hours of hypoxia followed by 6 hours of reoxygenation.Flow cytometry was used to detect cell apoptosis,DHE staining was used to assess cellular ROS levels,JC-1 immunofluorescence staining was used to evaluate mitochondrial membrane potential,and Western blot was used to detect mitochondrial autophagy-re-lated proteins.Results BMMSC-Exo treatment significantly alleviated oxidative stress,restored mitochondrial mem-brane potential,reduced mitochondrial autophagy levels,and effectively decreased cardiomyocyte apoptosis.Conclu-sions Bone marrow mesenchymal stem cell-derived exosomes alleviate H/R-induced cardiomyocyte injury.


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