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.Research progress on the correlation of dry eye with depression
Feng JIN ; Baoyue MI ; Jingqing MU ; Jingjing CAO ; Xia HUA
International Eye Science 2026;26(1):74-79
Dry eye disease is a chronic ocular surface disorder of multifactorial origin, characterized by a loss of tear film homeostasis and associated with a range of ocular discomfort symptoms. Growing evidence underscores a significant bidirectional relationship between dry eye and depression: individuals with dry eye disease exhibit a higher prevalence of depressive disorders, and conversely, those diagnosed with depression demonstrate an increased susceptibility to developing dry eye. This interplay is mediated through several pathophysiological pathways, such as chronic inflammation, cerebral functional alterations, gut microbiome dysregulation, and sleep disturbances, which may collectively sustain a vicious cycle. The use of antidepressant therapy introduces further complexity, exerting heterogeneous effects on dry eye—some agents may offer symptomatic relief, whereas others can aggravate ocular surface impairment. The mechanisms responsible for these differential outcomes remain incompletely elucidated and merit further investigation. This review systematically consolidates epidemiological data on the dry eye-depression link, examines potential shared pathological mechanisms, and evaluates current therapeutic options. We propose an integrated management approach that combines conventional dry eye treatments, such as traditional Chinese medicine, electroacupuncture, physical activity and antidepressants—a multimodal strategy that may yield synergistic benefits in alleviating both ocular and affective symptoms, thereby improving overall quality of life. Moving forward, research should focus on deciphering the underlying mechanistic pathways and facilitating the translation of these insights into clinical practice to inform targeted, combined treatment regimens for patients with dry eye and depression.
3.Triglyceride-glucose index and homocysteine in association with the risk of stroke in middle-aged and elderly diabetic populations
Xiaolin LIU ; Jin ZHANG ; Zhitao LI ; Xiaonan WANG ; Juzhong KE ; Kang WU ; Hua QIU ; Qingping LIU ; Jiahui SONG ; Jiaojiao GAO ; Yang LIU ; Qian XU ; Yi ZHOU ; Xiaonan RUAN
Shanghai Journal of Preventive Medicine 2025;37(6):515-520
ObjectiveTo investigate the triglyceride-glucose (TyG) index and the level of serum homocysteine (Hcy) in association with the incidence of stroke in type 2 diabetes mellitus (T2DM) patients. MethodsBased on the chronic disease risk factor surveillance cohort in Pudong New Area, Shanghai, excluding those with stroke in baseline survey, T2DM patients who joined the cohort from January 2016 to October 2020 were selected as the research subjects. During the follow-up period, a total of 318 new-onset ischemic stroke patients were selected as the case group, and a total of 318 individuals matched by gender without stroke were selected as the control group. The Cox proportional hazards regression model was used to adjust for confounding factors and explore the serum TyG index and the Hcy biochemical indicator in association with the risk of stroke. ResultsThe Cox proportional hazards regression results showed that after adjusting for confounding factors, the risk of stroke in T2DM patients with 10 μmol·L⁻¹
4.Serological and molecular biological analysis of a rare Dc- variant individual
Xue TIAN ; Hua XU ; Sha YANG ; Suili LUO ; Qinqin ZUO ; Liangzi ZHANG ; Xiaoyue CHU ; Jin WANG ; Dazhou WU ; Na FENG
Chinese Journal of Blood Transfusion 2025;38(8):1101-1106
Objective: To reveal the molecular biological mechanism of a rare Dc-variant individual using PacBio third-generation sequencing technology. Methods: ABO and Rh blood type identification, DAT, unexpected antibody screening and D antigen enhancement test were conducted by serological testing. The absorption-elution test was used to detect the e antigen. RHCE gene typing was performed by PCR-SSP, and the 1-10 exons of RHCE were sequenced by Sanger sequencing. The full-length sequences of RHCE, RHD and RHAG were detected by PacBio third-generation sequencing technology. Results: Serological findings: Blood type O, Dc-phenotype, DAT negative, unexpected antibody screening negative; enhanced D antigen expression; no detection of e antigen in the absorption-elution test. PCR-SSP genotyping indicated the presence of only the RHCE
c allele. Sanger sequencing results: Exons 5-9 of RHCE were deleted, exon 1 had a heterozygous mutation at c. 48G/C, and exon 2 had five heterozygous mutations at c. 150C/T, c. 178C/A, c. 201A/G, c. 203A/G and c. 307C/T. Third-generation sequencing results: RHCE genotype was RHCE
02N. 08/RHCE-D(5-9)-CE; RHD genotype was RHD
01/RHD
01; RHAG genotype was RHAG
01/RHAG
01 (c. 808G>A and c. 861G>A). Conclusion: This Dc-individual carries the allele RHCE
02N. 08 and the novel allele RHCE-D(5-9)-CE. The findings of this study provide data support and a theoretical basis for elucidating the molecular mechanisms underlying RhCE deficiency phenotypes.
5.Multi-omics Analysis of NUDT19 Across Cancer Types and Its Functional Role in Leukemia
Xiao-Jin LI ; Shuai FENG ; Zhong-Tao YUAN ; Tong-Hua YANG
Progress in Biochemistry and Biophysics 2025;52(10):2627-2649
ObjectiveRecent studies have highlighted the critical role of NUDT19 in the initiation, progression, and prognosis of specific cancer types. However, its involvement in pan-cancer analysis has not been fully characterized. This study aims to systematically explore the expression patterns, clinical significance, and immune-related functions of NUDT19 in various cancer types through multi-omics analysis, further revealing its potential role in cancer, particularly its functional and therapeutic target value in leukemia. MethodsTo achieve this goal, various bioinformatics approaches were employed to evaluate the expression patterns, clinical significance, and immune-related functions of NUDT19 in tumors and normal tissues. Additionally, we analyzed the mutation characteristics of NUDT19 and its relationship with epigenetic modifications. Using the single-cell analysis tool SingleCellBase, we explored the distribution of NUDT19 across different cell subpopulations in tumors. To validate these findings, qRT-PCR was used to measure NUDT19 expression levels in specific tumor cell lines, and we established acute myeloid leukemia (AML) cell lines (HL-60 and THP-1) to conduct NUDT19 knockdown and overexpression experiments, assessing its effects on leukemia cell proliferation, apoptosis, and invasion. ResultsPan-cancer analysis revealed the dysregulated expression of NUDT19 across multiple cancer types, which was closely associated with poor prognosis, clinical staging, and diagnostic markers. Furthermore, NUDT19 was significantly correlated with tumor biomarkers, immune-related genes, and immune cell infiltration in different cancers. Mutation analysis showed that multiple mutations in NUDT19 were significantly associated with epigenetic changes. Single-cell analysis revealed the heterogeneity of NUDT19 expression in cancer cells, suggesting its potentially diverse functional roles in different cell subpopulations. qRT-PCR experiments confirmed the significant upregulation of NUDT19 in various tumor cell lines. In AML cell lines, NUDT19 knockdown led to reduced cell proliferation and invasion, with increased apoptosis, while NUDT19 overexpression significantly enhanced cell proliferation and invasion while reducing apoptosis. ConclusionThis study demonstrates the diverse roles of NUDT19 in various cancer types, with a particularly prominent functional role in leukemia. NUDT19 is not only associated with tumor initiation and progression but may also influence cancer progression through the regulation of immune microenvironment and epigenetic mechanisms. Our research highlights the potential of NUDT19 as a therapeutic target, particularly for targeted therapies in malignancies such as leukemia, with significant clinical application prospects.
6.Prediction of Pulmonary Nodule Progression Based on Multi-modal Data Fusion of CCNet-DGNN Model
Lehua YU ; Yehui PENG ; Wei YANG ; Xinghua XIANG ; Rui LIU ; Xiongjun ZHAO ; Maolan AYIDANA ; Yue LI ; Wenyuan XU ; Min JIN ; Shaoliang PENG ; Baojin HUA
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(24):135-143
ObjectiveThis study aims to develop and validate a novel multimodal predictive model, termed criss-cross network(CCNet)-directed graph neural network(DGNN)(CGN), for accurate assessment of pulmonary nodule progression in high-risk individuals for lung cancer, by integrating longitudinal chest computed tomography(CT) imaging with both traditional Chinese and western clinical evaluation data. MethodsA cohort of 4 432 patients with pulmonary nodules was retrospectively analyzed. A twin CCNet was employed to extract spatiotemporal representations from paired sequential CT scans. Structured clinical assessment and imaging-derived features were encoded via a multilayer perceptron, and a similarity-based alignment strategy was adopted to harmonize multimodal imaging features across temporal dimensions. Subsequently, a DGNN was constructed to integrate heterogeneous features, where nodes represented modality-specific embeddings and edges denoted inter-modal information flow. Finally, model optimization was performed using a joint loss function combining cross-entropy and cosine similarity loss, facilitating robust classification of nodule progression status. ResultsThe proposed CGN model demonstrated superior predictive performance on the held-out test set, achieving an area under the receiver operating characteristic curve(AUC) of 0.830, accuracy of 0.843, sensitivity of 0.657, specificity of 0.712, Cohen's Kappa of 0.417, and F1 score of 0.544. Compared with unimodal baselines, the CGN model yielded a 36%-48% relative improvement in AUC. Ablation studies revealed a 2%-22% increase in AUC when compared to simplified architectures lacking key components, substantiating the efficacy of the proposed multimodal fusion strategy and modular design. Incorporation of traditional Chinese medicine (TCM)-specific symptomatology led to an additional 5% improvement in AUC, underscoring the complementary value of integrating TCM and western clinical data. Through gradient-weighted activation mapping visualization analysis, it was found that the model's attention predominantly focused on nodule regions and effectively captured dynamic associations between clinical data and imaging-derived features. ConclusionThe CGN model, by synergistically combining cross-attention encoding with directed graph-based feature integration, enables effective alignment and fusion of heterogeneous multimodal data. The incorporation of both TCM and western clinical information facilitates complementary feature enrichment, thereby enhancing predictive accuracy for pulmonary nodule progression. This approach holds significant potential for supporting intelligent risk stratification and personalized surveillance strategies in lung cancer prevention.
7.Knowledge of COVID-19 and associated factors among kidney transplant recipients and donors in Singapore.
Ian Tatt LIEW ; Yeli WANG ; Terence KEE ; Ping Sing TEE ; Rupesh Madhukar SHIRORE ; Sobhana THANGARAJU ; Quan Yao HO ; York Moi LU ; Jin Hua YONG ; Fiona FOO ; Eleanor NG ; Xia HE ; Constance LEE ; Shannon BAEY ; Marjorie FOO ; Tazeen Hasan JAFAR
Singapore medical journal 2025;66(2):81-90
BACKGROUND:
Effective interventions during the coronavirus disease 2019 (COVID-19) pandemic require an understanding of patients' knowledge and perceptions that influence their behaviour. Our study assessed knowledge of COVID-19 among kidney transplant recipients and donors, hitherto unevaluated.
METHODS:
We conducted a cross-sectional survey among 325 kidney transplant recipients and 172 donors between 1 May 2020 and 30 June 2020. The survey questionnaire assessed knowledge levels of COVID-19, sociodemographic data, health status, psychosocial impact of COVID-19 and precautionary behaviours during the pandemic.
RESULTS:
The mean COVID-19 knowledge score of the study population was 7.5 (standard deviation: 2.2) out of 10. The mean score was significantly higher among kidney recipients compared to kidney donors (7.9 [1.9] vs. 6.7 [2.6]; P <0.001). Younger age (21-49 vs. ≥50 years) and higher education (diploma and higher vs. secondary and lower) were associated with significantly higher knowledge scores in donors, but not among recipients ( P -interactions ≤0.01). In both kidney recipients and donors, financial concerns and/or social isolation were associated with lower knowledge levels.
CONCLUSIONS
Concerted efforts are needed to improve COVID-19 knowledge in kidney transplant recipients and donors, particularly older donors, donors with lower education and patients with financial concerns or feelings of social isolation. Intensive patient education may mitigate the impact of education levels on COVID-19 knowledge levels.
Humans
;
COVID-19/epidemiology*
;
Kidney Transplantation
;
Middle Aged
;
Singapore/epidemiology*
;
Male
;
Female
;
Adult
;
Cross-Sectional Studies
;
Health Knowledge, Attitudes, Practice
;
Transplant Recipients/psychology*
;
Surveys and Questionnaires
;
Tissue Donors/psychology*
;
SARS-CoV-2
;
Young Adult
;
Aged
;
Pandemics
8.Environmental sustainability in healthcare: impacts of climate change, challenges and opportunities.
Ethan Yi-Peng KOH ; Wan Fen CHAN ; Hoon Chin Steven LIM ; Benita Kiat Tee TAN ; Cherlyn Tze-Mae ONG ; Prit Anand SINGH ; Michelle Bee Hua TAN ; Marcus Jin Hui SIM ; Li Wen ONG ; Helena TAN ; Seow Yen TAN ; Wesley Chik Han HUONG ; Jonathan SEAH ; Tiing Leong ANG ; Jo-Anne YEO
Singapore medical journal 2025;66(Suppl 1):S47-S56
Environmental damage affects many aspects of healthcare, from extreme weather events to evolving population disease. Singapore's healthcare sector has the world's second highest healthcare emissions per capita, hampering the nation's pledge to reduce emissions by 2030 and achieve net zero emissions by 2050. In this review, we provide an overview of the impact environmental damage has on healthcare, including facilities, supply chain and human health, and examine measures to address healthcare's impact on the environment. Utilising the 'R's of sustainability - rethinking, reducing/refusing, reusing/repurposing/reprocessing, repairing, recycling and research - we have summarised the opportunities and challenges across medical disciplines. Awareness and advocacy to adopt strategies at institutional and individual levels is needed to revolutionise our environmental footprint and improve healthcare sustainability. By leveraging evidence from ongoing trials and integrating sustainable practices, our healthcare system can remain resilient against environment-driven challenges and evolving healthcare demands while minimising further impacts of environmental destruction.
Humans
;
Climate Change
;
Delivery of Health Care
;
Singapore
;
Conservation of Natural Resources
;
Sustainable Development
;
Environment
9.iPARTY study: Increasing pre-exposure prophylaxis access and reach via telehealth for young men who have sex with men in Singapore 2022-2023.
Pei Hua LEE ; Justin Y LIM ; P Arun KUMAR ; Zhi Hui TAN ; Rayen Bing Hui TAN ; Chiaw Yee CHOY ; Rayner Kay Jin TAN ; Martin Tw CHIO ; Chen Seong WONG
Annals of the Academy of Medicine, Singapore 2025;54(3):160-169
INTRODUCTION:
Although pre-exposure prophylaxis (PrEP) has been available in Singapore since 2016, its uptake among gay, bisexual and other men-who-have-sex-with-men (GBMSM) is low. The iPARTY study was established to evaluate the acceptability and feasibility of PrEP and a PrEP teleconsultation service for young GBMSM aged 18 to 29 years.
METHOD:
A total of 53 young GBMSM were enrolled in the iPARTY study. They had a total of 5 in-person consultations and teleconsultations, at 12-week intervals. Laboratory tests and quarterly baseline surveys were performed to assess PrEP adherence, sexual behaviour, and incidence of human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs).
RESULTS:
Thirty-five participants completed the entire 12-month follow-up. Most participants had positive experiences with PrEP teleconsultations. There was a statistically significant fall in participants' aggregate Patient Health Questionnaire-9 scores throughout the study. Self-reported PrEP adherence decreased over the course of the study, denoting improved mental health. Although self-reported condom use for anal intercourse and participants' risk perception of HIV decreased after PrEP adoption, there was no statisti-cally significant increase in STI incidence.
CONCLUSION
This pilot project has shown that PrEP services provide an opportunity for YMSM to access sexual health testing, treatment and counselling, and may even have tangible benefits on the mental health of this population. Teleconsultation is shown to be a suitable platform for the delivery of such services. Collaborative initiatives are crucial to further enhance the affordability and accessibility of PrEP in Singapore, and to improve patient adherence.
Adolescent
;
Adult
;
Humans
;
Male
;
Young Adult
;
Anti-HIV Agents/administration & dosage*
;
Feasibility Studies
;
Health Risk Behaviors
;
HIV Infections/psychology*
;
Incidence
;
Medication Adherence
;
Mental Health/statistics & numerical data*
;
Pilot Projects
;
Pre-Exposure Prophylaxis/statistics & numerical data*
;
Sexual and Gender Minorities/statistics & numerical data*
;
Sexually Transmitted Diseases/prevention & control*
;
Singapore/epidemiology*
;
Telemedicine/statistics & numerical data*
;
Homosexuality, Male/statistics & numerical data*
10.The impact of Anchor, a home visitation programme for maltreated children, on child developmental and behavioural outcomes.
Shi Hua CHAN ; Jean Yin OH ; Li Ming ONG ; Wen Hann CHOW ; Oh Moh CHAY ; Salam SOLIMAN ; Lourdes Mary DANIEL ; Pratibha AGARWAL ; Charmain Samantha TAN ; Jun Lin SAI ; Joanne Ferriol ESPECKERMAN ; Rehena SULTANA ; Cong Jin Wilson LOW ; Sita Padmini YELESWARAPU
Annals of the Academy of Medicine, Singapore 2025;54(4):208-218
INTRODUCTION:
Adverse childhood experiences (ACEs) are associated with significant long-term impacts, yet few interventions specifically target ACE exposure, especially in Asian populations. Anchor, Singapore's first home visitation programme, addresses maltreat-ment among preschool children. This study evaluated Anchor's impact on children's developmental and behavioural outcomes.
METHOD:
We conducted a prospective evaluation of children under 4 years assessed for maltreatment from November 2019 to July 2023. Developmental and behavioural progress was measured every 6 months using the Ages and Stages Questionnaires (ASQ-3) and ASQ:Social-Emotional (ASQ:SE-2), and annually using the Child Behaviour Checklist (CBCL).
RESULTS:
The results of 125 children (mean age 20.0 months, 48% female) were analysed. The mean length of stay in programme was 21.2 (7.3) months. At baseline, 92 (73.6%) children were at risk of develop-mental delay and 25 (31.7%) children aged ≥18 months had behavioural concerns. The programme was associated with significant improvements in gross motor (P=0.002) and fine motor (P=0.001) domains of the ASQ-3 and internalising problem scale (P=0.001) of the CBCL.
CONCLUSION
Anchor effectively enhances develop-mental and behavioural outcomes for children exposed to maltreatment. Targeted early intervention through such programmes can mitigate adverse impacts, optimising developmental trajectories and potentially reducing the long-term clinical and economic burdens associated with ACEs.
Humans
;
Female
;
Male
;
Child Abuse/therapy*
;
Child, Preschool
;
Singapore
;
House Calls
;
Infant
;
Prospective Studies
;
Child Development
;
Developmental Disabilities/epidemiology*
;
Program Evaluation
;
Child Behavior Disorders
;
Child Behavior

Result Analysis
Print
Save
E-mail