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.Sclera Vessel Segmentation Based on Fusion Filtering and Reflection Suppression
Ming-Xuan FAN ; Zong-Qing MA ; Chu-Xiang GAO ; Yi-Xuan SHI ; Zi-Hang ZHANG ; Zhe-Xuan JIA ; Fan FAN ; Guo-Liang HUANG ; Jiang ZHU
Progress in Biochemistry and Biophysics 2026;53(5):1195-1206
ObjectiveIn traditional Chinese medicine (TCM), the foundational doctrine that the eyes reflect the essence of the internal viscera establishes ocular observation as a cornerstone of diagnostic practice. Specifically, the morphological characteristics and coloration variations of the scleral microvasculature serve as critical clinical indicators for assessing the dynamic balance of Qi and Blood, as well as the pathological status of internal organs. Historically, however, TCM eye diagnosis has relied predominantly on the subjective clinical experience and visual acuity of individual practitioners, leading to inherent challenges in standardization and reproducibility. While automated computer-aided diagnostic systems offer a promising solution, existing vessel segmentation algorithms encounter significant domain-specific bottlenecks when applied to scleral imagery. These challenges primarily stem from the highly reflective and moist nature of the ocular surface, which generates severe reflective interference. Furthermore, the inherent low contrast of fine capillary networks against complex background textures, compounded by non-uniform illumination, frequently results in high false-positive rates, misdetections, and severe vessel fragmentation. To address these critical limitations and advance the objective quantification of TCM diagnostics, this paper proposes a novel, highly robust sclera vessel segmentation framework that innovatively integrates Frangi-Sato dual-filter adaptive enhancement with pixel-level reflection detection. MethodsThe proposed methodology systematically addresses the segmentation pipeline through three synergistic stages. First, to overcome the structural limitations of single-filter approaches, a multi-scale weighted fusion strategy is meticulously designed to harness the complementary extraction capabilities of both Frangi and Sato filters. This adaptive enhancement optimally balances the preservation of main vessel trunk continuity with the heightened sensitivity required for delineating delicate, low-contrast peripheral capillaries. Second, to tackle the persistent issue of reflective highlights, a sophisticated multi-feature synergistic reflection detection module is introduced. By jointly analyzing local information entropy, gradient field variations, and intensity statistical distributions, this module achieves precise, pixel-level identification and elimination of reflective artifacts without compromising the underlying vascular structures. Finally, a dual-level adaptive thresholding strategy, featuring an innovative “core protection” mechanism, is implemented. This critical step effectively suppresses complex background noise while rigorously preserving the structural and topological integrity of the intricate vessel network, preventing the structural breaks often seen in conventional binarization methods. ResultsThe efficacy of the proposed framework was rigorously evaluated using both self-constructed clinical datasets specifically acquired for TCM research and standardized public datasets. Extensive experimental results demonstrate that the proposed method consistently outperforms state-of-the-art traditional approaches and contemporary deep learning models. Specifically, the proposed method achieves a Dice similarity coefficient of approximately 0.71 on the private clinical dataset, and secures the best performance across the majority of quantitative metrics on both datasets. Notably, the framework exhibits exceptional robustness and generalization capabilities in highly challenging scenarios characterized by intense reflective interference, low signal-to-noise ratios, and cross-domain image variations. ConclusionThis study successfully realizes the high-integrity, automated segmentation of scleral vessel networks under complex clinical imaging conditions. By overcoming the fundamental algorithmic challenges of reflection interference and micro-vessel loss, the proposed methodology provides potential support for the digitization, objective standardization, and intelligent advancement of modern TCM eye diagnosis systems.
3.Sclera Vessel Segmentation Based on Fusion Filtering and Reflection Suppression
Ming-Xuan FAN ; Zong-Qing MA ; Chu-Xiang GAO ; Yi-Xuan SHI ; Zi-Hang ZHANG ; Zhe-Xuan JIA ; Fan FAN ; Guo-Liang HUANG ; Jiang ZHU
Progress in Biochemistry and Biophysics 2026;53(5):1195-1206
ObjectiveIn traditional Chinese medicine (TCM), the foundational doctrine that the eyes reflect the essence of the internal viscera establishes ocular observation as a cornerstone of diagnostic practice. Specifically, the morphological characteristics and coloration variations of the scleral microvasculature serve as critical clinical indicators for assessing the dynamic balance of Qi and Blood, as well as the pathological status of internal organs. Historically, however, TCM eye diagnosis has relied predominantly on the subjective clinical experience and visual acuity of individual practitioners, leading to inherent challenges in standardization and reproducibility. While automated computer-aided diagnostic systems offer a promising solution, existing vessel segmentation algorithms encounter significant domain-specific bottlenecks when applied to scleral imagery. These challenges primarily stem from the highly reflective and moist nature of the ocular surface, which generates severe reflective interference. Furthermore, the inherent low contrast of fine capillary networks against complex background textures, compounded by non-uniform illumination, frequently results in high false-positive rates, misdetections, and severe vessel fragmentation. To address these critical limitations and advance the objective quantification of TCM diagnostics, this paper proposes a novel, highly robust sclera vessel segmentation framework that innovatively integrates Frangi-Sato dual-filter adaptive enhancement with pixel-level reflection detection. MethodsThe proposed methodology systematically addresses the segmentation pipeline through three synergistic stages. First, to overcome the structural limitations of single-filter approaches, a multi-scale weighted fusion strategy is meticulously designed to harness the complementary extraction capabilities of both Frangi and Sato filters. This adaptive enhancement optimally balances the preservation of main vessel trunk continuity with the heightened sensitivity required for delineating delicate, low-contrast peripheral capillaries. Second, to tackle the persistent issue of reflective highlights, a sophisticated multi-feature synergistic reflection detection module is introduced. By jointly analyzing local information entropy, gradient field variations, and intensity statistical distributions, this module achieves precise, pixel-level identification and elimination of reflective artifacts without compromising the underlying vascular structures. Finally, a dual-level adaptive thresholding strategy, featuring an innovative “core protection” mechanism, is implemented. This critical step effectively suppresses complex background noise while rigorously preserving the structural and topological integrity of the intricate vessel network, preventing the structural breaks often seen in conventional binarization methods. ResultsThe efficacy of the proposed framework was rigorously evaluated using both self-constructed clinical datasets specifically acquired for TCM research and standardized public datasets. Extensive experimental results demonstrate that the proposed method consistently outperforms state-of-the-art traditional approaches and contemporary deep learning models. Specifically, the proposed method achieves a Dice similarity coefficient of approximately 0.71 on the private clinical dataset, and secures the best performance across the majority of quantitative metrics on both datasets. Notably, the framework exhibits exceptional robustness and generalization capabilities in highly challenging scenarios characterized by intense reflective interference, low signal-to-noise ratios, and cross-domain image variations. ConclusionThis study successfully realizes the high-integrity, automated segmentation of scleral vessel networks under complex clinical imaging conditions. By overcoming the fundamental algorithmic challenges of reflection interference and micro-vessel loss, the proposed methodology provides potential support for the digitization, objective standardization, and intelligent advancement of modern TCM eye diagnosis systems.
4.Discussion on processing time for Polygonatum kingianum based on analysis of correlation between sugar components and color changes
GUO Hong ; YAO Rui ; LI Zhe ; FAN Jing ; WANG Ying ; GUO Xiaohan ; CHEN Jia ; DUAN Baozhong ; YANG Jianbo ; JING Wenguang ; CHENG Xianlong ; WEI Feng
Drug Standards of China 2026;27(1):0083-0091
Objective: To investigate the correlation between color parameters (L*, a*, b*, Eab*) and the contents of reducing sugars, total polysaccharides, total oligosaccharides, as well as four saccharides (fructose, glucose, sucrose, and kestose) during the nine cycles of steaming and sun-drying processing of Polygonatum kingianum, and to preliminarily explore the optimal processing duration.
Methods: The color changes were objectively evaluated using a colorimeter. The anthrone-sulfuric acid method was employed to determine total polysaccharides and oligosaccharides. The 3,5-dinitrosalicylic acid (DNS) colorimetric method was used to measure total reducing sugar content. High-performance liquid chromatography coupled with charged aerosol detection (HPLC-CAD) was applied for quantitative analysis of fructose, glucose, sucrose, and kestose. Multivariate statistical analysis was conducted to assess samples from different processing stages.
Results: Significant variations in color and component contents were observed across processing stages. The herbal pieces progressively darkened with increased processing cycles: brightness (L*) and total color difference (Eab*) initially decreased then stabilized, while a* (red-green) and b* (yellow-blue) values first increased then declined. Total polysaccharides and oligosaccharides showed overall decreasing trends, whereas reducing sugars initially increased before stabilizing. Fructose and glucose levels rose continuously, while sucrose and kestose decreased progressively, becoming undetectable after five cycles.
Conclusion: The chromatic alteration and saccharide composition of P. kingianum showed significant correlation with processing duration. Both total color difference (Eab*) and reducing sugar content stabilized after four processing cycles (12 hours), suggesting that four cycles of steaming and sun-drying may represent the optimal processing duration.
5.Analytical research on processing techniques of Polygoni Multiflori Radix Praeparata based on chemical composition and color changes correlation
YAO Rui ; GUO Hong ; LI Zhe ; GUO Xiaohan ; ZHANG Xiaoshu ; DUAN Baozhong ; YANG Jianbo ; CHEN Jia ; JING Wenguang ; CHENG Xianlong ; WEI Feng
Drug Standards of China 2026;27(1):0100-0108
Objective: To investigate the correlation between the color parameters (L*, a*, b*, Eab* values) of Polygoni Multiflori Radix Praeparata powder prepared by different processing techniques and the contents of 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucopyranoside, emodin, physcion, emodin-8-O-β-D-glucopyranoside, physcion-8-O-β-D-glucopyranoside.
Methods: The L*, a*, b* and Eab* values of Polygoni Multiflori Radix Praeparata powder prepared by different processing techniques were determined by spectrophotometer, and the contents of the five components were determined by high performance liquid chromatography. Secondly, SPSS 26.0 software and Simca 14.1 software were used to analyze the correlation.
Results: Through the hierarchical cluster analysis (HCA), it was found that the steamed samples and black bean steamed samples could be obviously divided into two categories: raw products and processed products. The processed products could be further divided into 2-8 h and 12-48 h. Pearson correlation analysis showed that the content of stilbene glycoside was significantly positively correlated with L*, a* and b* values (P<0.01). The a* value was significantly positively correlated with the content of emodin and physcion (P<0.01). Emodin-8-O-β-D-glucoside was positively correlated with L* value and b* value, while physcion-8-O-β-D-glucoside was negatively correlated with a* value. Partial least squares discriminant analysis (PLS) showed that 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside (VIP=1.69) and emodin-8-O-β-D-glucoside (VIP=1.06) were the key variables affecting chromaticity characteristics (P<0.01).
Conclusion: The three processes of steaming, black bean steaming and black bean stewing are consistent in composition transformation and chromaticity variation, and stilbene glycoside can be used as a specific index component to characterize the processed color. Chromatic parameters can effectively reflect the processing progression and serve as quality monitoring indicators during production.
6.The United Nations'global procurement for health products and pathways for China's participation:A case study of United Nations International Children's Emergency Fund
Zhe-yi FANG ; Xiao-long HU ; Jia-yan HUANG
Chinese Journal of Health Policy 2025;18(8):71-79
United Nations(UN)agencies are key actors in global procurement of health products,with the United Nations Children's Fund(UNICEF)currently accounting for the largest share of UN procurement expenditures.This study developed a conceptual framework to analyze the processes of UN's global procurement for health products.Based on this framework,the study analyzed the mechanisms and key characteristics of UN procurement practices,identified potential challenges faced by Chinese products and suppliers seeking to engage with the UN's global procurement.The findings indicate a steady increase in the volume of Chinese products procured and their alignment with the UN's sustainable procurement policies.However,Chinese suppliers still face notable barriers,including gaps in technical standards,bidding and contracting capacities,and price competitiveness.In addition,the strategic compliance capabilities of Chinese suppliers and products,such as the ability to offer strategically valuable products and build long-term partnership,remains limited.Based on this,the study recommends that China enhance its participation and influence in the UN health procurements by stabilizing the production capacity,promoting knowledge-sharing among suppliers to enhance their engagement capabilities,and improving the long-term strategic competitiveness of Chinese enterprises in the global market.
7.Molecular mechanisms and prospects for disease treatment of ciliogenesis and autophagy
Hao-liang HU ; Jin WANG ; Jia-yan LIU ; Shi-fang HUANG ; Yu-ting LI ; Zhe CHEN ; Lin-xi CHEN
Chinese Pharmacological Bulletin 2025;41(4):631-637
Cilia,as cellular sensory organelles,actively partici-pate in and regulate cellular processes such as autophagy and metabolic breakdown during their generation and transportation.Autophagy,on the other hand,is a cell self-protection mecha-nism that maintains cellular homeostasis by clearing aggregates and damaged organelles.Combining recent research findings,this review comprehensively elucidates the bidirectional crosstalk between primary cilia and autophagy.Specifically,it highlights the crucial role of cilia-dependent signaling pathways in activa-ting cellular autophagy and how autophagy regulates cilia genera-tion and length by degrading specific ciliary proteins.Moreover,the dysregulation of primary cilia and autophagy is closely asso-ciated with the clinical manifestations and pathogenesis of vari-ous ciliopathy-related diseases such as polycystic kidney disease and tuberous sclerosis.In terms of pharmacotherapy,this review provides a comprehensive and in-depth overview of small mole-cule inhibitors targeting ciliogenesis,including cytoskeletal drugs and Hedgehog signaling pathway inhibitors.Despite the current limitations in clinical use,these drugs lay the groundw-ork for developing highly specific targeted small molecule inhibi-tors of ciliogenesis and for the treatment of ciliopathies and canc-ers.By systematically discussing ciliogenesis,autophagy,disea-ses and drugs,this review offers new insights for further elucida-ting the crosstalk between ciliogenesis and autophagy,exploring their pathological mechanisms in disease development,and de-veloping therapeutic strategies in the future.
8.Global procurement of health products by international multilateral organizations and China's participation:A case study of the Global Fund
Xiao-long HU ; Zhe-yi FANG ; Jia-yan HUANG
Chinese Journal of Health Policy 2025;18(1):73-81
Global procurement of health products is an important way for multilateral organizations in the health field to perform their functions.As one of the most important multilateral organizations in the global health field today,the Global Fund to Fight AIDS,Tuberculosis and Malaria occupies a huge share of the global procurement market for health products.This article introduces in detail the procurement methods of the Global Fund and the quality standards of its procured products;also it describes and analyzes the total amount of funds procured by the Global Fund,the types of procured health products,the main supply countries and their changing trends over time.Corresponding policy suggestions therefore are proposed for China to better participate in the governance of global health and for Chinese related companies to enter the international procurement market.
9.Impact of hydroxy-safflower yellow A on regeneration and repair capabilities of human umbilical cord mesenchymal stem cells
Yu-kang SUN ; Yan-zhe DUAN ; Jian-lin HUA ; Wei-hao JIA ; Jie-zhong YU ; Cun-gen MA ; Lei JIA ; Rui-ping ZHANG ; Xiao-yan ZHAI
Chinese Pharmacological Bulletin 2025;41(9):1643-1650
Aim To investigate the effects of hydroxyl-safflor yellow A(HSYA)on the regenerative and re-pair functions of human umbilical cord mesenchymal stem cells(hUC-MSCs).Methods hUC-MSCs were mechanically isolated,and their morphology was ob-served.Cell surface marker expression was analyzed u-sing flow cytometry.Osteogenic differentiation was used to confirm the multipotency of the cells.The cells were treated with various concentrations of HSYA(0,100,200,400,600 μmol·L-1),and the optimal con-centration and duration of treatment were determined u-sing the CCK-8 assay.Cells were divided into four groups:control,100,200,and 400 μmol·L-1.The proliferative capacity of hUC-MSCs was assessed by EdU incorporation.Vascular endothelial growth factor(VEGF)and brain-derived neurotrophic factor(BD-NF)levels in the culture supernatant were measured u-sing enzyme-linked immunosorbent assays.Cell migra-tion ability was evaluated by Scratch assays.The ex-pression levels of VEGF,BDNF,and fibroblast growth factor 2(FGF2)were detected by Western blotting.Results The isolated cells exhibited characteristics consistent with stem cell surface markers and demon-strated osteogenic and adipogenic differentiation poten-tial.After 48 hours of treatment,no cytotoxicity was observed at concentrations of 100,200,and 400 μmol·L-1compared to the control group.HSYA signifi-cantly increased the number of EdU-positive cells and cell migration rate,with the most pronounced effect was achieved at 200 μmol·L-1(P<0.01).VEGF and BDNF levels in the supernatant were elevated,with the highest expression observed at 200 μmol·L-1(P<0.01).Similarly,the expression levels of BDNF,VEGF,and FGF2 were significantly upregulated in the HSYA groups,with the highest levels at 200 μmol·L-1(P<0.01).Conclusion HSYA promotes the proliferation,migration and angiogenesis of hUC-MSCs,with an optimal concentration of 200 μmol·L-1.
10.Progress and application of lyophilization technology in forensic DNA testing
Yuling CUI ; Hao YU ; Zhe ZHANG ; Lina JIA ; Jing WANG ; Xue BAI
Chinese Journal of Forensic Medicine 2025;40(3):343-347
Freeze-drying technique,also known as lyophilization,is a process of removing moisture from a solution or suspension through freezing and vacuum dehydration to maintain the stability of the samples and prolong their shelf life.Freeze-drying technology has been widely used in food,pharmaceutical,clinical testing,chemical and other fields but its application in the field of forensic medicine has just started.Polymerase chain reaction(PCR)and its derivative detection technologies are widely used in forensic DNA detection,but PCR reagents need to be stored and transported at low temperature.In recent years,forensic scientists have begun applying freeze-drying technology to PCR amplification reagents to solve the transportation and storage problems of PCR reagents.In order to promote the application of PCR freeze-drying technology in forensic genetics,this paper mainly expounds the research course,system and process of PCR freeze-drying technology,compares the advantages and disadvantages of PCR reagents with traditional PCR reagents,and introduces the advantages and challenges of PCR freeze-drying reagents in forensic medicine.

Result Analysis
Print
Save
E-mail