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.Effect of Shenqi Jianxin Formula(参芪健心方)on Mitochondrial Autophagy and the PINK1/Parkin Signaling Pathway in Cardiac Tissues in Chronic Heart Failure
Peichi XIE ; Pan LIU ; Zitong DING ; Jingyi BAI ; Deqi PANG ; Xiaohua DAI
Journal of Traditional Chinese Medicine 2026;67(4):447-455
ObjectiveTo explore the potential mechanism of Shenqi Jianxin Formula (参芪健心方) in the treatment of chronic heart failure (CHF) from the perspective of regulating mitochondrial autophagy via the PTEN-induced kinase 1 (PINK1)/E3 ubiquitin ligase (Parkin) pathway. MethodsMale SD rats were subjected to abdominal aortic constriction to establish the CHF model. Twenty-four successfully modeled rats were randomly divided into the model group, sacubitril/valsartan group, and low- and high-dose Shenqi Jianxin Formula groups, with 6 rats in each group. Six other rats were set as the sham surgery group, which were only separated the abdominal aorta and then closed the abdomen. Rats in the low-dose and high-dose Shenqi Jianxin Formula groups were given intragastric administration of Shenqi Jianxin Formula suspension at doses of 4.41 g/(kg·d) and 17.64 g/(kg·d), respectively; the sacubitril/valsartan group received intragastric administration of sacubitril/valsartan sodium tablet suspension at 10 mg/(kg·d); the sham surgery group and the model group were given normal saline at 10 ml/(kg·d) via intragastric gavage. The intervention lasted for 4 consecutive weeks. Cardiac function indices including left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were detected, and serum brain natriuretic peptide (BNP) content was measured. HE staining and Masson staining were used to observe myocardial histopathological changes. Transmission electron microscopy was employed to examine the ultrastructure of cardiac tissues. Quantitative real-time polymerase chain reaction (Rt-qPCR) was performed to determine the mRNA expressions of PINK1/Parkin pathway-related factors and autophagy-associated proteins including Beclin-1, p62, and microtubule-associated protein 1 light chain 3 (LC3) in myocardial tissues. ResultsCompared with the sham surgery group, the model group showed significant decreases in LVEF and LVFS levels, an increase in serum BNP content, down-regulated mRNA and protein expressions of PINK1, Parkin and Beclin-1 in cardiac tissues, up-regulated mRNA and protein expressions of p62, as well as significant reductions in LC3B mRNA expression, phosphorylated PTEN-induced kinase 1 (p-PINK1) and phosphorylated E3 ubiquitin ligase (p-Parkin) protein levels, and the ratio of microtubule-associated protein 1 light chain 3-Ⅱ to microtubule-associated protein 1 light chain 3-Ⅰ (LC3Ⅱ/LC3Ⅰ) (P<0.05). Pathological results revealed obvious myocardial cell edema, necrosis and degeneration, increased disorder of myocardial fiber arrangement, extensive inflammatory cell infiltration, moderate to severe mitochondrial swelling, a few mitochondrial vacuolar changes, and no obvious autophagy in the field of vision in the model group. Compared with the model group, all the above indicators were significantly improved in the high-dose Shenqi Jianxin Formula group and the sacubitril/valsartan group (P<0.05). Moreover, the improvement of each index in the high-dose Shenqi Jianxin Formula group was superior to that in the low-dose group (P<0.05). In the high-dose Shenqi Jianxin Formula group, myocardial myofibrils were arranged regularly with orderly orientation, the striated structure was clear, and necrotic cells significantly reduced. ConclusionShenqi Jianxin Formula can activate the PINK1/Parkin signaling pathway in myocardial tissues, enhance mitochondrial autophagy, and clear dysfunctional mitochondria, thereby improving cardiac function and delaying the progression of CHF.
3.Roles and mechanism of bile acids and gut microbiota in primary biliary cholangitis
Mengyao WU ; Jiayin PAN ; Rong DING ; Jinyu LI ; Wenlin TAI
Journal of Clinical Hepatology 2026;42(4):957-964
Primary biliary cholangitis (PBC) is a cholestatic autoimmune liver disease characterized by the injury of small intrahepatic bile ducts, and at present, the pathogenesis of PBC remains unclear. Recent studies have shown that bile acid metabolism disorder and gut microbiota imbalance play a key role in the development and progression of PBC, and they form a complex and dynamic interaction network via the “gut-liver axis” and regulate core physiopathological processes such as immune response, metabolic homeostasis, and inflammatory response in a synergistic manner. This article systematically elaborates on the abnormal features of bile acid metabolism and gut microbiota in PBC, discusses their synergistic mechanisms in PBC, and then proposes a combined strategy of targeting bile acid receptors and modulating gut microbiota, in order to overcome the limitations of current treatment modalities and provide new insights and directions for the clinical management of PBC.
4.Hot issues and application prospects of small molecule drugs in treatment of osteoarthritis
Shuai YU ; Jiawei LIU ; Bin ZHU ; Tan PAN ; Xinglong LI ; Guangfeng SUN ; Haiyang YU ; Ya DING ; Hongliang WANG
Chinese Journal of Tissue Engineering Research 2025;29(9):1913-1922
BACKGROUND:Various proteins,signaling pathways,and inflammatory mediators are involved in the pathophysiological process of osteoarthritis.The development of small molecule drugs targeting these proteins,signaling pathways,and inflammatory mediators can effectively delay the progression of osteoarthritis and ameliorate its clinical manifestations. OBJECTIVE:To review the research progress of small molecule drugs in the treatment of osteoarthritis based on the pathogenesis of osteoarthritis. METHODS:PubMed,CNKI,and WanFang databases were searched with English search terms"osteoarthritis,arthritis,osteoarthrosis,degenerative,arthritides,deformans,small molecule drugs,small molecule inhibitors,small molecule agents"and Chinese search terms"osteoarthritis,small molecule drugs,small molecule inhibitors."A total of 68 articles were included for review according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION:(1)Currently,studies concerning the pathogenesis of osteoarthritis remain unclear.The occurrence and development of osteoarthritis are strongly associated with proteins,cytokines,and signal transduction pathways,so its therapeutic mechanism is relatively complex.Currently,targeting proteins,cytokines,and signal transduction pathways related to osteoarthritis with small molecule drugs has become a major research focus.(2)Small molecule drugs frequently possess visible intracellular or extracellular targets and efficacy,containing enhancing cartilage repair,resisting joint degradation,attenuating inflammation,and relieving pain.Other anti-osteoarthritis small molecule drugs have shown promise in promoting stem cell chondrogenic differentiation and cartilage matrix reconstruction.(3)At present,small molecule drugs targeting the pathophysiological process of osteoarthritis to delay the progression of osteoarthritis are still in the experimental stage,but most of these small molecule drugs have shown the expected results in the experimental process,and there are no relevant studies to illustrate the efficacy of small molecule drugs in the treatment of osteoarthritis.(4)Small molecule drugs for the treatment of osteoarthritis have reached the expected experimental results in the basic experimental stage.Numerous studies have exhibited that small molecule drugs can target the suppression of specific proteins,cytokines,and signal transduction pathways that cause osteoarthritis,so as to treat osteoarthritis.Nevertheless,its safety and effectiveness still need to be identified by further basic and clinical studies.This process needs to be investigated and studied by more scholars.(5)At present,many scholars in and outside China have made contributions to the treatment of osteoarthritis.Compared with traditional treatment methods,small molecule drugs reveal better efficacy and safety in the basic experimental stage,and it is expected to become an emerging method for the treatment of osteoarthritis in the future to rid patients of pain.
5.Dynamic Sequential Diagnosis and Treatment of Pediatric Nephrotic Syndrome Based on the "Sweat Pore-Qi and Liquid-Kidney Collaterals"
Zhenhua YUAN ; Mingyang CAI ; Yingying JIANG ; Jingjing WU ; Wenqing PAN ; Zichao DING ; Shuzi ZHANG ; Xianqing REN
Journal of Traditional Chinese Medicine 2025;66(10):1007-1010
Based on the viewpoint of "sweat pore-qi and liquid-kidney collaterals", it is believed that children's nephrotic syndrome is caused by the core mechanism of sweat pore constraint and closure, qi and liquid imbalance, and kidney collaterals impairment, and it is proposed that the treatment principle is to nourish the sweat pore, regulate qi and fluid, and supplement the kidney and unblock the collaterals. In clinic, guided by sequential therapy and according to the different disease mechanism characteristics of the four stages, including early stage of the disease, hormone induction stage, hormone reduction stage, hormone maintenance stage, the staged dynamic identification and treatment was applied. For early stage of the disease with edema due to yang deficiency, modified Zhenwu Decoction (真武汤) was applied to warm yang and drain water; for hormone induction stage with yin deficiency resulting in effulgent fire, modified Zhibai Dihuang Pill (知柏地黄丸) plus Erzhi Pill (二至丸) was used to enrich yin and reduce fire; for hormone reduction stage with qi and yin deficiency, modified Shenqi Dihuang Decoction (参芪地黄汤) was used to boost qi and nourish yin; for hormone maintenance stage, modified Shenqi Pill (肾气丸) was used to supplement yin and yang. Meanwhile, the treatment also attaches importance to the combination of vine-based or worm medicinals to dredge collaterals, so as to providing ideas for clinical treatment.
6.The value of BRAF V600E mutation detection and liquid-based thin-preparation cytology in preoperative diagnosis of papillary thyroid carcinoma
Yiqing PAN ; Jie ZHENG ; Qingquan FANG ; Lihong DING
Chinese Archives of Otolaryngology-Head and Neck Surgery 2025;32(4):210-214
OBJECTIVE To evaluate the value of BRAF V600E mutation detection combined with liquid-based thin-preparation cytologic test(LCT)in the preoperative diagnosis of papillary thyroid carcinoma(PTC)and the related pathological characteristics of BRAF V600E mutation.METHODS Clinical data of 428 patients with thyroid nodules who underwent surgery at the First Affiliated Hospital of Xiamen University from January 2023 to December 2023 were retrospectively analyzed.All patients underwent ultrasound-guided fine needle aspiration and liquid-based cytology diagnosis and BRAF V600E gene mutation detection simultaneously before surgery.RESULTS The results of BRAF V600E mutation were significantly correlated with the results of liquid-based cytology diagnosis in patients(P<0.01).The area under the curve(AUC value)of LCT was 0.88,and the AUC value of BRAF V600E was 0.84.The sensitivity and specificity of LCT for preoperative diagnosis of PTC were 0.80 and 0.96,respectively.The sensitivity and specificity of BRAF V600E for preoperative diagnosis of PTC were 0.72 and 0.96,respectively.The AUC value of LCT combined with BRAF V600E for the diagnosis of PTC was 0.93 while the sensitivity and specificity were 0.88 and 0.92,respectively.The combined diagnosis significantly improved the sensitivity and specificity of thyroid nodule disease diagnosis,with a statistically significant difference(Z=-5.50,-4.60,P<0.001).In addition,BRAF V600E mutation was associated with the age of patients,the maximum diameter of nodules,and whether the capsule was invaded,with significant statistical differences between groups(P<0.05),but was not associated with gender,whether the nodules were multifocal,whether lymph node metastasis occurred,or whether Hashimoto's thyroiditis was present.CONCLUSION The combination of FNA liquid-based thin-preparation cytologic test and BRAF V600E detection can significantly improve the preoperative diagnostic accuracy of PTC.
7.Evaluation methods for the rehabilitation efficacy of bidirectional closed-loop motor imagery brain-computer interface active rehabilitation training systems.
He PAN ; Peng DING ; Fan WANG ; Tianwen LI ; Lei ZHAO ; Wenya NAN ; Anmin GONG ; Yunfa FU
Journal of Biomedical Engineering 2025;42(3):431-437
The bidirectional closed-loop motor imagery brain-computer interface (MI-BCI) is an emerging method for active rehabilitation training of motor dysfunction, extensively tested in both laboratory and clinical settings. However, no standardized method for evaluating its rehabilitation efficacy has been established, and relevant literature remains limited. To facilitate the clinical translation of bidirectional closed-loop MI-BCI, this article first introduced its fundamental principles, reviewed the rehabilitation training cycle and methods for evaluating rehabilitation efficacy, and summarized approaches for evaluating system usability, user satisfaction and usage. Finally, the challenges associated with evaluating the rehabilitation efficacy of bidirectional closed-loop MI-BCI were discussed, aiming to promote its broader adoption and standardization in clinical practice.
Brain-Computer Interfaces
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Humans
;
Imagination/physiology*
;
Imagery, Psychotherapy/methods*
8.Research on prediction model of protein thermostability integrating graph embedding and network topology features.
Shuyi PAN ; Xiaoyang XIANG ; Qunfang YAN ; Yanrui DING
Journal of Biomedical Engineering 2025;42(4):817-823
Protein structure determines function, and structural information is critical for predicting protein thermostability. This study proposes a novel method for protein thermostability prediction by integrating graph embedding features and network topological features. By constructing residue interaction networks (RINs) to characterize protein structures, we calculated network topological features and utilize deep neural networks (DNN) to mine inherent characteristics. Using DeepWalk and Node2vec algorithms, we obtained node embeddings and extracted graph embedding features through a TopN strategy combined with bidirectional long short-term memory (BiLSTM) networks. Additionally, we introduced the Doc2vec algorithm to replace the Word2vec module in graph embedding algorithms, generating graph embedding feature vector encodings. By employing an attention mechanism to fuse graph embedding features with network topological features, we constructed a high-precision prediction model, achieving 87.85% prediction accuracy on a bacterial protein dataset. Furthermore, we analyzed the differences in the contributions of network topological features in the model and the differences among various graph embedding methods, and found that the combination of DeepWalk features with Doc2vec and all topological features was crucial for the identification of thermostable proteins. This study provides a practical and effective new method for protein thermostability prediction, and at the same time offers theoretical guidance for exploring protein diversity, discovering new thermostable proteins, and the intelligent modification of mesophilic proteins.
Neural Networks, Computer
;
Algorithms
;
Protein Stability
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Proteins/chemistry*
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Protein Conformation
;
Temperature
9.Gradient damage pattern of hair cell loss in cochlear explants induced by gentamicin
Xu PAN ; Weijun XUAN ; Dalian DING
Journal of Audiology and Speech Pathology 2025;33(4):381-385
Objective To study the gradient damage pattern of cochlear explants hair cells induced by genta-micin in vitro culture.Methods After diluting gentamicin to concentrations of 0 mM,0.1 mM,0.5 mM,1.0 mM,1.5 mM,and 3.0 mM in culture medium,the cochlear basement membrane was cultured in vitro(10 cochlea in each group).After 24 hours,FITC-conjugated phalloidin staining was used to specifically display the static cilia of cochlear hair cells.The morphology and quantity of hair cells in the cochlear basement membrane were observed under a fluorescence microscope.After 12 hours,24 hours,and 36 hours(10 cochlea in each group),Rhodamine was used to label the accumulation of 0.5 mM gentamicin content at different positions in cochlear ex-plants.Results After culturing the cochlear basement membrane with different concentrations of gentamicin for 24 hours,0.1 mM gentamicin had little damage to cochlear hair cells,with no significant difference.Gentamicin at concentrations of 0.5 mM,1.0 mM,1.5 mM,and 3.0 mM caused damage to cochlear hair cells,with the most se-vere damage occurring in the basal gyrus hair cells and gradually progressing towards the apical gyrus hair cells.The accumulation of gentamicin first occurred in the outer hair cells of the basal gyrus,and gradually spread towards the inner hair cells of the basal gyrus and the inner and outer hair cells of the parietal gyrus with increasing culture time.The degree of damage gradually worsened with the increase of gentamicin dosage,and the damage was significant and concentration time dependent.Conclusion Through the in vitro culture method of rat cochlear explants,it was found that gentamicin could cause gradient damage to hair cells in cochlear explants.
10.Micronucleus counts correlating with male infertility: a clinical analysis of chromosomal abnormalities and reproductive parameters.
Shun-Han ZHANG ; Ying-Jun XIE ; Wen-Jun QIU ; Qian-Ying PAN ; Li-Hao CHEN ; Jian-Feng WU ; Si-Qi HUANG ; Ding WANG ; Xiao-Fang SUN
Asian Journal of Andrology 2025;27(4):537-542
Investigating the correlation between micronucleus formation and male infertility has the potential to improve clinical diagnosis and deepen our understanding of pathological progression. Our study enrolled 2252 male patients whose semen was analyzed from March 2023 to July 2023. Their clinical data, including semen parameters and age, were also collected. Genetic analysis was used to determine whether the sex chromosome involved in male infertility was abnormal (including the increase, deletion, and translocation of the X and Y chromosomes), and subsequent semen analysis was conducted for clinical grouping purposes. The participants were categorized into five groups: normozoospermia, asthenozoospermia, oligozoospermia, oligoasthenozoospermia, and azoospermia. Patients were randomly selected for further study; 41 patients with normozoospermia were included in the control group and 117 patients with non-normozoospermia were included in the study group according to the proportions of all enrolled patients. Cytokinesis-block micronucleus (CBMN) screening was conducted through peripheral blood. Statistical analysis was used to determine the differences in micronuclei (MNi) among the groups and the relationships between MNi and clinical data. There was a significant increase in MNi in infertile men, including those with azoospermia, compared with normozoospermic patients, but there was no significant difference between the genetic and nongenetic groups in azoospermic men. The presence of MNi was associated with sperm concentration, progressive sperm motility, immotile spermatozoa, malformed spermatozoa, total sperm count, and total sperm motility. This study underscores the potential utility of MNi as a diagnostic tool and highlights the need for further research to elucidate the underlying mechanisms of male infertility.
Humans
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Male
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Infertility, Male/genetics*
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Adult
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Micronucleus Tests
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Semen Analysis
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Oligospermia/genetics*
;
Azoospermia/genetics*
;
Chromosome Aberrations
;
Sperm Count
;
Micronuclei, Chromosome-Defective
;
Middle Aged

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