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.Effects of SPBC1604.04 Gene Deletion on Mitotic Cell Dynamics in Schizosaccharomyces pombe
Jia-Ni XU ; Jia-Yi HE ; Lang-Lin ZHENG ; Shu-Rong HE ; Shuai MA ; Xiang DING ; Yi-Ling HOU
Progress in Biochemistry and Biophysics 2026;53(5):1471-1484
ObjectiveMitochondria are not only the central organelles responsible for cellular energy metabolism but also play essential roles in regulating cell cycle progression and cytoskeletal dynamics. In recent years, accumulating evidence has demonstrated that mitochondrial homeostasis is closely associated with mitotic progression and cytokinesis. Schizosaccharomyces pombe serves as a classical and well-established model organism. Because its cell cycle regulatory mechanisms are highly conserved throughout evolution, its genetic background is clearly defined, and experimental manipulation is efficient and convenient, it has been extensively applied in studies of cell growth, division, and reproductive mechanisms. The SPBC1604.04 gene encodes a previously uncharacterized mitochondrial carrier protein in Schizosaccharomyces pombe. This gene is located on chromosome II and spans 1 018 base pairs in length. It encodes a protein consisting of 238 amino acids with a predicted molecular mass of approximately 31.03 ku. Bioinformatic analysis predicts that this protein is responsible for the transport of thiamine pyrophosphate (TPP) into mitochondria. However, the effects of SPBC1604.04 gene deletion on mitotic cell dynamics under different temperature conditions have not been fully elucidated. MethodsThe SPBC1604.04 deletion strain of Schizosaccharomyces pombe was used as the experimental model. Fluorescent protein markers were constructed in the deletion background to label mitochondria, microtubules, actin, myosin, the nuclear envelope, and chromosomes. Live-cell imaging was performed using a TCS-SP8 laser scanning confocal microscope under normal temperature conditions (25℃) and heat stress conditions (37℃). Time-lapse microscopy was applied to dynamically monitor mitochondrial morphology and distribution, spindle assembly and elongation, chromosome segregation, as well as the formation and constriction of the actomyosin ring during cytokinesis. ImageJ software was used for quantitative measurements, including microtubule length during mitosis, spindle length at different mitotic stages, mitochondrial fluorescence intensity as an indicator of mitochondrial content, actomyosin ring length, nuclear envelope area, and chromosome segregation timing. Statistical analyses were conducted to compare phenotypic differences between the wild-type and SPBC1604.04 deletion strains at both temperature conditions. Through these analyses, we systematically investigated the impact of SPBC1604.04 deletion on mitotic cell dynamics in fission yeast under both normal physiological conditions and temperature stress. ResultsAt 25℃, compared with wild-type cells, the SPBC1604.04Δ strain exhibited a pronounced tendency toward mitochondrial fragmentation, accompanied by abnormal mitochondrial content and a significant reduction in mitochondrial fluorescence intensity. These observations suggest impaired mitochondrial homeostasis under normal growth conditions. In addition, the constriction time of actomyosin ring during cytokinesis was markedly prolonged, indicating that deletion of SPBC1604.04 affects the dynamics of the contractile machinery. However, no obvious defects were observed in spindle assembly, spindle elongation, or chromosome segregation. Under heat stress at 37℃, mitochondrial morphology in the SPBC1604.04Δ strain showed a tendency to recover toward a continuous tubular network structure. Mitochondrial content was restored, fluorescence intensity increased, and the constriction time of the actomyosin ring returned to levels comparable to those of wild-type cells. These results indicate that the mitotic defects observed at normal temperature are partially or fully alleviated under heat stress conditions. ConclusionThis study demonstrates that deletion of the SPBC1604.04 gene leads to abnormal mitochondrial content in Schizosaccharomyces pombe. The mitochondrial carrier protein SPBC1604.04 participates in regulating actomyosin ring constriction during mitosis but does not appear to be directly involved in the regulation of spindle dynamics or chromosome segregation. Our findings provide key experimental evidence for understanding the functional link between the SPBC1604.04 gene, mitochondrial homeostasis, and mitotic regulation.
3.Effects of SPBC1604.04 Gene Deletion on Mitotic Cell Dynamics in Schizosaccharomyces pombe
Jia-Ni XU ; Jia-Yi HE ; Lang-Lin ZHENG ; Shu-Rong HE ; Shuai MA ; Xiang DING ; Yi-Ling HOU
Progress in Biochemistry and Biophysics 2026;53(5):1471-1484
ObjectiveMitochondria are not only the central organelles responsible for cellular energy metabolism but also play essential roles in regulating cell cycle progression and cytoskeletal dynamics. In recent years, accumulating evidence has demonstrated that mitochondrial homeostasis is closely associated with mitotic progression and cytokinesis. Schizosaccharomyces pombe serves as a classical and well-established model organism. Because its cell cycle regulatory mechanisms are highly conserved throughout evolution, its genetic background is clearly defined, and experimental manipulation is efficient and convenient, it has been extensively applied in studies of cell growth, division, and reproductive mechanisms. The SPBC1604.04 gene encodes a previously uncharacterized mitochondrial carrier protein in Schizosaccharomyces pombe. This gene is located on chromosome II and spans 1 018 base pairs in length. It encodes a protein consisting of 238 amino acids with a predicted molecular mass of approximately 31.03 ku. Bioinformatic analysis predicts that this protein is responsible for the transport of thiamine pyrophosphate (TPP) into mitochondria. However, the effects of SPBC1604.04 gene deletion on mitotic cell dynamics under different temperature conditions have not been fully elucidated. MethodsThe SPBC1604.04 deletion strain of Schizosaccharomyces pombe was used as the experimental model. Fluorescent protein markers were constructed in the deletion background to label mitochondria, microtubules, actin, myosin, the nuclear envelope, and chromosomes. Live-cell imaging was performed using a TCS-SP8 laser scanning confocal microscope under normal temperature conditions (25℃) and heat stress conditions (37℃). Time-lapse microscopy was applied to dynamically monitor mitochondrial morphology and distribution, spindle assembly and elongation, chromosome segregation, as well as the formation and constriction of the actomyosin ring during cytokinesis. ImageJ software was used for quantitative measurements, including microtubule length during mitosis, spindle length at different mitotic stages, mitochondrial fluorescence intensity as an indicator of mitochondrial content, actomyosin ring length, nuclear envelope area, and chromosome segregation timing. Statistical analyses were conducted to compare phenotypic differences between the wild-type and SPBC1604.04 deletion strains at both temperature conditions. Through these analyses, we systematically investigated the impact of SPBC1604.04 deletion on mitotic cell dynamics in fission yeast under both normal physiological conditions and temperature stress. ResultsAt 25℃, compared with wild-type cells, the SPBC1604.04Δ strain exhibited a pronounced tendency toward mitochondrial fragmentation, accompanied by abnormal mitochondrial content and a significant reduction in mitochondrial fluorescence intensity. These observations suggest impaired mitochondrial homeostasis under normal growth conditions. In addition, the constriction time of actomyosin ring during cytokinesis was markedly prolonged, indicating that deletion of SPBC1604.04 affects the dynamics of the contractile machinery. However, no obvious defects were observed in spindle assembly, spindle elongation, or chromosome segregation. Under heat stress at 37℃, mitochondrial morphology in the SPBC1604.04Δ strain showed a tendency to recover toward a continuous tubular network structure. Mitochondrial content was restored, fluorescence intensity increased, and the constriction time of the actomyosin ring returned to levels comparable to those of wild-type cells. These results indicate that the mitotic defects observed at normal temperature are partially or fully alleviated under heat stress conditions. ConclusionThis study demonstrates that deletion of the SPBC1604.04 gene leads to abnormal mitochondrial content in Schizosaccharomyces pombe. The mitochondrial carrier protein SPBC1604.04 participates in regulating actomyosin ring constriction during mitosis but does not appear to be directly involved in the regulation of spindle dynamics or chromosome segregation. Our findings provide key experimental evidence for understanding the functional link between the SPBC1604.04 gene, mitochondrial homeostasis, and mitotic regulation.
4.PERK-mediated inhibition of endoplasmic reticulum stress in lipopolysaccharide-induced inflammatory responses in microglia
Jia-Xin DING ; Meng-Jun LÜ ; Lin-Xia LU ; Ci-Li JIFU ; Jun XIA ; Jing-Tao WANG
Acta Anatomica Sinica 2025;56(4):421-430
Objective To explore the role of the protein kinase R-like endoplasmic reticulum kinase(PERK)-mediated endoplasmic reticulum stress pathway in a model of lipopolysaccharide(LPS)-induced microglia inflammation.Methods To investigate its effects on endoplasmic reticulum(ER)stress,an inflammation model of microglia was established by stimulating with LPS at gradient concentrations for 24 hours and with 1 mg/L LPS for different durations.Cell viability was assessed by the CCK-8 assay;The mRNA and protein expression levels of related inflammatory factors were measured by Real-time PCR and ELISA kits.Cellular oxidative stress was evaluated by detecting reactive oxygen species(ROS),and Real-time PCR and Western blotting were used to examine the mRNA and protein expression levels of ER stress pathway markers associated with inflammation.Results 1.The effects of different concentrations of LPS on cell viability and morphology were not statistically significant after acting on BV-2 cells for 24 hours(P>0.05);2.1 mg/L LPS incubated with BV-2 cells for different times and the cell viability decreased with the increase of time;3.Compared with the 0 hour group,the levels of pro-inflammatory cytokine interleukin(IL)-1β,tumor necrosis factor-α(TNF-α)mRNA and protein expression increased significantly(P<0.05)in the LPS-stimulated 9 hours,12 hours,and 24 hours groups,and the inflammation model was successfully established;4.Compared with the 0 hour group,the protein and mRNA expression levels of the endoplasmic reticulum stress pathway-related indexes in the LPS-stimulated 9 hours,12 hours,and 24 hours groups increased significantly(P<0.01),which showed the time-dependence;5.After adding the PERK inhibitor GSK2606414,the mRNA and protein expression levels of endoplasmic reticulum stress-related indicators in the PERK inhibitor group were significantly reduced compared with those in the LPS group(P<0.05);6.The mRNA and protein expression levels of pro-inflammatory cytokines and the fluorescence intensity of ROS in the PERK inhibitor group were significantly reduced compared with those in the LPS group(P<0.01).Conclusion Targeting PERK-mediated endoplasmic reticulum stress inhibits LPS-induced inflammatory responses in microglia.
5.A cohort study of the correlation between triglyceride-glucose index variability and new-onset hyperuricemia
Qiuyue JIA ; Jingfeng CHEN ; Youxiang WANG ; Lin WANG ; Suying DING
Chinese Journal of Endocrinology and Metabolism 2025;41(2):99-105
Objective:To evaluate the association between triglyceride-glucose(TyG) index level, their variability, and the risk of incident hyperuricemia(HUA).Methods:A total of 1 583 cases with good compliance who underwent follow-up at the health examination center of a tertiary hospital physical in Zhengzhou were enrolled. The TyG index mean(TyG-mean) and variability indexes, including standard deviation(TyG-SD), coefficient of variation(TyG-CV), and adjusted standard deviation(adj-TyG-SD), were calculated based on TyG index values from three consecutive annual health check-ups. Cox proportional risk regression model was used to assess the relationship between the variability of TyG index and the risk of new-onset HUA; the dose-response relationship between different TyG indexes and HUA was examined using restricted cubic spline(RCS). Results:After a 3-year follow-up, 146 participants developed incident HUA. Both TyG-mean and TyG index variability indicators were significantly higher in the HUA group compared to the non-HUA group( P<0.05). After adjusting for multiple confounders, each standard deviation σincrease in TyG-SD, TyG-CV, and adj-TyG-SD was associated with a 1.23-fold(95% CI 1.06-1.43), 1.22-fold(95% CI 1.05-1.42), and 1.26-fold(95% CI 1.08-1.45) higher risk of incident HUA, respectively. RCS analysis revealed a nonlinear association between adj-TyG-SD and HUA risk( P<0.05), with a critical threshold of 0.55 at a hazard ratio( HR) of 1. Conclusions:Increased TyG index variability is associated with a higher risk of incident HUA, with adj-TyG-SD showing the strongest correlation with HUA risk.
6.Prediction of testicular histology in azoospermia patients through deep learning-enabled two-dimensional grayscale ultrasound.
Jia-Ying HU ; Zhen-Zhe LIN ; Li DING ; Zhi-Xing ZHANG ; Wan-Ling HUANG ; Sha-Sha HUANG ; Bin LI ; Xiao-Yan XIE ; Ming-De LU ; Chun-Hua DENG ; Hao-Tian LIN ; Yong GAO ; Zhu WANG
Asian Journal of Andrology 2025;27(2):254-260
Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans
;
Male
;
Azoospermia/diagnostic imaging*
;
Deep Learning
;
Testis/pathology*
;
Retrospective Studies
;
Adult
;
Ultrasonography/methods*
;
Sperm Retrieval
;
Sertoli Cell-Only Syndrome/diagnostic imaging*
7.Preparation and Evaluation of Clinical-Grade Human Umbilical Cord-Derived Mesenchymal Stem Cells with High Expression of Hematopoietic Supporting Factors.
Jie TANG ; Pei-Lin LI ; Xiao-Yu ZHANG ; Xiao-Tong LI ; Fu-Hao YU ; Jia-Yi TIAN ; Run-Xiang XU ; Bo-Feng YIN ; Li DING ; Heng ZHU
Journal of Experimental Hematology 2025;33(3):892-898
OBJECTIVE:
To prepare clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSC) with high expression of hematopoietic supporting factors and evaluate their stem cell characteristics.
METHODS:
Fetal umbilical cord tissues were collected from healthy postpartum women during full-term cesarean section. Wharton's jelly was mechanically separated and hUC-MSCs were obtained by explant culture method and enzyme digestion method in an animal serum-free culture system with addition of human platelet lysate. The phenotypic characteristics of hUC-MSCs obtained by two methods were detected by flow cytometry. The differences in proliferation ability between the two groups of hUC-MSCs were identified through CCK-8 assay and colony forming unit-fibroblast (CFU-F) assay. The differences in multilineage differentiation potential between the two groups of hUC-MSCs were identified through induction of adipogenic, osteogenic, and chondrogenic differentiation. The mRNA expression levels of hematopoietic supporting factors such as SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in the two groups of hUC-MSCs were identified by real-time fluorescence quantiative PCR(RT-qPCR).
RESULTS:
The results of flow cytometry showed that hUC-MSCs obtained by the two methods both expressed high levels of CD73, CD90 and CD105, while lowly expressed CD31, CD45 and HLA-DR. The results of CCK-8 and CFU-F assay showed that the proliferation ability of hUC-MSCs obtained by explant culture method was better than those obtained by enzyme digestion method. The results of the triple lineage differentiation experiment showed that there was no significant difference in multilineage differentiation potential between the two grous of hUC-MSCs. The results of RT-qPCR showed that the mRNA expression levels of hematopoietic supporting factors SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in hUC-MSCs obtained by explant cultrue method were higher than those obtained by enzyme digestion method.
CONCLUSION
Clinical-grade hUC-MSCs with high expression levels of hematopoietic supporting factors were successfully cultured in an animal serum-free culture system.
Humans
;
Mesenchymal Stem Cells/metabolism*
;
Umbilical Cord/cytology*
;
Cell Differentiation
;
Female
;
Cell Proliferation
;
Cells, Cultured
;
Chemokine CXCL12/metabolism*
;
Angiopoietin-1/metabolism*
;
Vascular Cell Adhesion Molecule-1/metabolism*
;
Stem Cell Factor/metabolism*
;
Flow Cytometry
;
Pregnancy
8.Integrative transcriptomic and epigenomic analysis identifies BCL6B as a novel regulator of human pluripotent stem cell to endothelial differentiation.
Yonglin ZHU ; Jinyang LIU ; Jia WANG ; Shuangyuan DING ; Hui QIU ; Xia CHEN ; Jianying GUO ; Peiliang WANG ; Xingwu ZHANG ; Fengzhi ZHANG ; Rujin HUANG ; Fuyu DUAN ; Lin WANG ; Jie NA
Protein & Cell 2025;16(11):985-990
9.Interpretation of the Standard Establishment Approach and Compilation Rationale for Metallic Pharmaceutical Packaging Standard Development in the 2025 Edition of the Pharmacopeia of the People's Republic of China
Fangfang ZHANG ; Rong CAI ; Wanling LAN ; Lei CHEN ; Lin YAO ; Hao DING ; Weiyi LU ; Yaju ZHOU ; Fenglan ZHANG ; Yuan LIU ; Kai XU ; Liang CHANG ; Yan LIU ; Feifei JIA ; Ying LI ; Yan JIANG ; Dandan WANG ; Shengli WU ; Yong SHEN ; Xiangwei XU ; Yanggege LYU
Herald of Medicine 2025;44(11):1745-1751
To analyze the standard establishment approach and compilation rationale for metallic pharmaceutical packaging standard development in the 2025 edition of the Pharmacopeia of the People's Republic of China.This article systematically explained the background and process of establishing the guiding principles for metallic materials and containers used in pharmaceutical packaging in the Chinese Pharmacopoeia through basic information,relevant domestic and international standards,the establishment of key quality attributes of metallic pharmaceutical packaging materials,and the construction of metallic pharmaceutical packaging material standards.The newly established guidelines,the Pharmacopeia of the People's Republic of China 9625,prioritized product critical quality attributes(CQAs)and real-world applicability.This dual emphasis on rigidity and adaptability enhances drug safety,meets the regulatory requirements,and promotes the globalization and scientific advancement of China's pharmaceutical packaging industry.
10.Research progress in laboratory artificial breeding technologies for ticks
Xiao-nan DONG ; Lian-yang SUN ; Hao CUI ; Jia-mei KANG ; Yu-lin DING ; Yong-hong LIU ; Li ZHAO
Chinese Journal of Zoonoses 2025;41(1):67-74
As the world's second largest vector of pathogens,ticks can spread a variety of pathogens by sucking the host's blood.Ticks not only threaten human life and health,but also cause great economic losses in animal husbandry.Artificial breeding of ticks can provide a stable environment for the growth and reproduction of ticks,thereby generating sufficient exper-imental materials for understanding ticks'biological characteristics,studying tick-borne pathogens,and developing anti-tick drugs and vaccines.Current methods of breeding ticks in the laboratory can be roughly divided into two categories:breeding methods using host animals or artificial membranes.The selection of breeding method must be comprehensively considered,ac-cording to tick types,blood-sucking habits,living environments,and other aspects.The development processes of the two methods,and their respective advantages and disadvantages,are described and discussed,to assist laboratories in artificial breeding of ticks.

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