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.

ObjectiveTo explore the mechanism by which Xianglian Huazhuo prescription ameliorates chronic atrophic gastritis （CAG） through regulating the Golgi protein 73 （GP73）/protein kinase R-like endoplasmic reticulum kinase （PERK）/activating transcription factor 4 （ATF4） signaling pathway and modulating endoplasmic reticulum stress （ERS）. MethodA mouse model of CAG was induced by multiple factors， including ranitidine， N-methyl-N′-nitro-N-nitrosoguanidine （MNNG）， and irregular feeding. The CAG mice were randomized into five groups： model， Morodan （2.0 g·kg^-1）， and high-dose， medium-dose， and low-dose （7.6， 3.8， 1.9 g·kg^-1， respectively） Xianglian Huazhuo prescription， with 10 mice in each group. At the same time， 10 mice in normal group were set up. The mice in the Morodan group and the high-dose， medium-dose， and low-dose groups of Xianglian Huazhuo prescription were administrated with corresponding agents by gavage， and those in the normal group and the model group were administrated with an equal volume of normal saline. All the mice were intervened once a day for 60 consecutive days. After the last administration， the overall morphological changes of the gastric tissue were observed. Hematoxylin-eosin （HE） staining and transmission electron microscopy （TEM） were used to evaluate the pathological morphology and the endoplasmic reticulum ultrastructure in the gastric tissue. The serum levels of pepsinogen Ⅰ （PGⅠ）， pepsinogen Ⅱ （PGⅡ）， gastrin-17 （G-17）， and GP73 were determined by enzyme-linked immunosorbent assay （ELISA）. The pepsinogen ratio （PGR， PGⅠ/PGⅡ） was calculated. The protein levels of GP73， PERK， phosphorylated （p）-PERK， glucose-regulated protein 78 （GRP78）， ATF4， CCAAT enhancer-binding protein homologous protein （CHOP）， cysteinyl aspartate-specific protease-12 （Caspase-12）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） were assessed by Western blot. The expression of GRP78 was detected by immunofluorescence （IF） assay， and the location of Bcl-2 and Bax by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed pale gastric mucosa with flattened folds and reduced and loosely arranged gastric mucosal glands， declined serum levels of PGI， PGR， G-17， and GP73 （P<0.01）. downregulated protein levels of GP73， p-PERK， ATF4， GRP78， CHOP， Caspase-12， and Bax in the gastric tissue， and upregulated protein level of Bcl-2 （P<0.01）. Compared with the model group， the Morodan group and each Xianglian Huazhuo prescription group exhibited red gastric mucosa with increased folds， alleviated pathological damage， swelling endoplasmic reticulum， elevated serum levels of PGI， G-17， and GP73 （P<0.05， P<0.01）， and upregulated protein levels of Caspase-12 and Bax and downregulated protein level of Bcl-2 in the gastric tissue （P<0.05， P<0.01）. The Morodan group and the high-dose and medium-dose Xianglian Huazhuo prescription groups exhibited increased serum level of PGR （P<0.05， P<0.01） and upregulated protein levels of GP73， p-PERK， ATF4， GRP78， and CHOP in the gastric tissue （P<0.05， P<0.01）. ConclusionXianglian Huazhuo prescription can activate the GP73/PERK/ATF4 signaling pathway and induce ERS-mediated apoptosis to alleviate the pathological damage of the gastric mucosa， thereby demonstrating a protective effect against CAG in mice.

Inteins are unique protein insertion sequences capable of self-excision, enabling the covalent ligation of flanking extein peptides via amide bond formation. This process proceeds spontaneously without requiring external enzymes, cofactors, or chemical reagents, granting inteins exceptional biocompatibility and traceless performance in protein engineering applications. Split inteins represent a specialized and versatile subclass whose splicing domains are encoded by two separate gene fragments rather than a single continuous open reading frame. These fragments, known as the N-terminal (IntN) and C-terminal (IntC) split inteins, associate through non-covalent interactions including hydrophobic forces, hydrogen bonds, and van der Waals forces to assemble into an active three-dimensional structure, which then drives efficient extein ligation and enables protein trans-splicing. Protein trans-splicing mediated by split inteins has become a cornerstone for traceless protein ligation owing to its high specificity and irreversibility, fundamentally reshaping strategies for protein modification, assembly, and functional regulation. Compared with traditional chemical ligation methods, split intein systems require no complex chemical derivatization of peptide fragments and can operate efficiently at micromolar concentrations under physiological conditions, thus avoiding structural and functional damage caused by organic reagents. In contrast to enzymatic ligation tools such as sortase, split inteins eliminate the need for additional enzymes or cofactors, simplifying reaction systems, reducing costs, and minimizing non-specific side products. These distinctive advantages render split inteins highly promising for applications in chemical biology, synthetic biology, and biopharmaceutical development. In recent years, deepened mechanistic understanding has established structure-guided rational design as the primary approach to overcoming key limitations of split inteins, including intrinsic aggregation propensity, strict extein sequence dependence, and limited splicing efficiency. Bioinformatic tools have been used to identify aggregation-prone regions in the IntN fragment, and site-directed mutagenesis of hydrophobic residues, relocation of split sites, or removal of misfolding-prone sequences has substantially reduced in vitro aggregation and improved soluble expression and assembly activity. Rational engineering of catalytic residues and adjacent flexible loops has relaxed strict amino acid preferences at extein junctions, enhancing sequence tolerance and reducing the risk of functional impairment in target proteins. Consensus design based on multiple sequence alignments has yielded ultra-fast splicing variants such as Cfa DnaE and Cat-TerL, which exhibit significantly accelerated kinetics and improved tolerance to denaturing conditions. Meanwhile, advances in structural biology have further clarified the conformational dynamics and catalytic mechanisms of splicing, supporting the precise design of high-performance intein modules. On this basis, electrostatic interaction tuning and metagenomic screening have yielded multiple mutually orthogonal split intein pairs, enabling selective multi-fragment protein ligation and providing new routes for the efficient synthesis of large multi-domain functional proteins. With these engineered split inteins offering continuously improved performance and expanded applicability, protein trans-splicing has been widely applied in numerous cutting-edge areas of protein research and biomedicine. In gene delivery, split intein-based systems overcome the packaging limit of adeno-associated viral vectors, enabling the accurate reconstitution of large therapeutic proteins and base editors in target cells, thereby enhancing the efficacy and scope of gene therapy for genetic diseases. In internal protein sequence editing, split inteins mediate precise sequence replacement and modification in flexible regions or loops of target proteins, without the need for complex multi-step ligation and protein refolding involved in traditional protein semisynthesis. In protein-protein interaction studies, intein-mediated splicing covalently captures transient and weak intracellular complexes, enabling sensitive, high-throughput interaction detection and drug screening. In synthetic biology, conditionally controllable splicing systems support the construction of diverse intracellular and cell-surface biological logic gates for the precise regulation of cellular behavior. In mechanistic biochemical research, split inteins enable photocatalytic proximity labeling and site-specific tagging, allowing the preparation of homogeneous protein samples carrying precise post-translational modifications such as ubiquitination and polyglutamylation for chromatin interactome analysis and epigenetic studies. Moreover, covalent trapping strategies using split inteins stabilize transient enzymatic intermediates, providing unprecedented insights into molecular mechanisms such as nucleosome ubiquitination that are difficult to elucidate using conventional methods. This review systematically summarizes key technological advances in split inteins over the past decade, highlighting engineering strategies, mechanistic insights, and the development of orthogonal components. It comprehensively surveys emerging applications at the frontiers of protein research, analyzes current core challenges, and proposes future directions, particularly emphasizing artificial intelligence-driven de novo design and novel splicing pathways to break existing technical bottlenecks. By enabling traceless, efficient, and versatile protein manipulation, split inteins continue to serve as indispensable tools that drive innovation in protein engineering and fundamental life science research.

Acute kidney injury (AKI) is a prevalent and life-threatening clinical syndrome characterised by a rapid decline in renal function and diverse pathological etiologies. The condition has been demonstrated to be associated with elevated mortality rates and an increased risk of progression to chronic kidney disease. At present, clinicians depend heavily on conventional functional markers, such as serum creatinine and urine output, for the diagnosis and staging of the disease. It is evident that these conventional indicators characteristically manifest a considerable temporal delay and only undergo modification subsequent to considerable tissue damage. This severely restricts the timeframe for early detection and timely therapeutic intervention. Furthermore, standard markers fail to provide specific biological information regarding the underlying cellular injury mechanisms. The utilisation of advanced probe technologies in molecular imaging offers a robust alternative to overcome these inherent diagnostic limitations.This comprehensive review systematically evaluates recent progress in the design and application of two primary categories of molecular imaging tools for acute kidney disease, specifically reactive probes and enzyme-activated probes. Reactive probes are engineered to specifically interact with redox-active chemical species, including hydrogen peroxide, peroxynitrite, hypochlorous acid, and sulfur dioxide. Because oxidative stress constitutes a primary early event in acute renal tubular damage, these probes enable researchers and clinicians to visualize early cellular injury and radical accumulation well before global renal functional decline becomes evident. We discuss the application of these reactive probes across multiple imaging modalities including fluorescence imaging, magnetic resonance imaging (MRI), positron emission tomography (PET), and photoacoustic techniques. Photoacoustic imaging combines high spatial resolution with deep tissue penetration and has successfully demonstrated the ability to provide diagnostic alerts up to 12 h before any detectable rise in serum creatinine levels. Additionally, specific reactive probes have shown promising translational potential when tested by high-throughput screening in clinical human urine samples. Enzyme-activated probes target the specific catalytic activity of disease-relevant enzymes. These include well-documented renal tubular structural biomarkers such as NAG, GGT, and ALP, along with apoptosis-related caspases and specific nitroreductases. By responding only to enzymatic cleavage, these tools provide highly specific and pathology-directed imaging readouts. Recent structural design strategies in this field have advanced significantly beyond single-enzyme detection. Researchers are now focusing on sophisticated dual-target recognition to minimize background noise, multimodal integration to cross-validate imaging signals, and theranostic applications where probes simultaneously deliver diagnostic feedback and therapeutic agents to injured tissues. Nanotechnology serves as a fundamental enabler for realizing these advanced probe functions. By precisely optimizing nanoparticle parameters such as hydrodynamic size, surface charge, and targeting ligands, researchers can achieve amplified signal output, highly precise kidney delivery, and protection against premature degradation in the systemic circulation. For example, modifying surface charges can significantly enhance the active uptake of nanoprobes by damaged renal tubular epithelial cells.While preclinical probe development has progressed rapidly, moving these technologies into routine clinical practice remains a major challenge. We analyze the translational feasibility and current obstacles from biological, technological, and regulatory perspectives. Although biological targets such as KIM-1, FAP, and ALP have been validated in extensive patient cohorts, practical barriers severely limit their immediate clinical application. These obstacles involve complex changes in in vivo pharmacokinetics. During an acute injury episode, the extreme drop in the glomerular filtration rate alters probe clearance and can cause unwanted systemic accumulation or confusing background imaging signals. Other major hurdles include a lack of comprehensive long-term toxicity data and the absence of standardized manufacturing protocols to ensure batch-to-batch consistency. Future successful translation will require rigorous multi-center clinical studies to confirm the true diagnostic value of these probes over traditional markers. Researchers must also establish strict standardization of imaging procedures and comprehensive safety evaluations. Ultimately, this review provides a thorough reference framework for designing clinically translatable molecular probes and building a precision diagnostic imaging system for acute kidney injury.

ObjectiveTo explore the mechanism by which Xianglian Huazhuo prescription ameliorates chronic atrophic gastritis （CAG） through regulating the Golgi protein 73 （GP73）/protein kinase R-like endoplasmic reticulum kinase （PERK）/activating transcription factor 4 （ATF4） signaling pathway and modulating endoplasmic reticulum stress （ERS）. MethodA mouse model of CAG was induced by multiple factors， including ranitidine， N-methyl-N′-nitro-N-nitrosoguanidine （MNNG）， and irregular feeding. The CAG mice were randomized into five groups： model， Morodan （2.0 g·kg^-1）， and high-dose， medium-dose， and low-dose （7.6， 3.8， 1.9 g·kg^-1， respectively） Xianglian Huazhuo prescription， with 10 mice in each group. At the same time， 10 mice in normal group were set up. The mice in the Morodan group and the high-dose， medium-dose， and low-dose groups of Xianglian Huazhuo prescription were administrated with corresponding agents by gavage， and those in the normal group and the model group were administrated with an equal volume of normal saline. All the mice were intervened once a day for 60 consecutive days. After the last administration， the overall morphological changes of the gastric tissue were observed. Hematoxylin-eosin （HE） staining and transmission electron microscopy （TEM） were used to evaluate the pathological morphology and the endoplasmic reticulum ultrastructure in the gastric tissue. The serum levels of pepsinogen Ⅰ （PGⅠ）， pepsinogen Ⅱ （PGⅡ）， gastrin-17 （G-17）， and GP73 were determined by enzyme-linked immunosorbent assay （ELISA）. The pepsinogen ratio （PGR， PGⅠ/PGⅡ） was calculated. The protein levels of GP73， PERK， phosphorylated （p）-PERK， glucose-regulated protein 78 （GRP78）， ATF4， CCAAT enhancer-binding protein homologous protein （CHOP）， cysteinyl aspartate-specific protease-12 （Caspase-12）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） were assessed by Western blot. The expression of GRP78 was detected by immunofluorescence （IF） assay， and the location of Bcl-2 and Bax by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed pale gastric mucosa with flattened folds and reduced and loosely arranged gastric mucosal glands， declined serum levels of PGI， PGR， G-17， and GP73 （P<0.01）. downregulated protein levels of GP73， p-PERK， ATF4， GRP78， CHOP， Caspase-12， and Bax in the gastric tissue， and upregulated protein level of Bcl-2 （P<0.01）. Compared with the model group， the Morodan group and each Xianglian Huazhuo prescription group exhibited red gastric mucosa with increased folds， alleviated pathological damage， swelling endoplasmic reticulum， elevated serum levels of PGI， G-17， and GP73 （P<0.05， P<0.01）， and upregulated protein levels of Caspase-12 and Bax and downregulated protein level of Bcl-2 in the gastric tissue （P<0.05， P<0.01）. The Morodan group and the high-dose and medium-dose Xianglian Huazhuo prescription groups exhibited increased serum level of PGR （P<0.05， P<0.01） and upregulated protein levels of GP73， p-PERK， ATF4， GRP78， and CHOP in the gastric tissue （P<0.05， P<0.01）. ConclusionXianglian Huazhuo prescription can activate the GP73/PERK/ATF4 signaling pathway and induce ERS-mediated apoptosis to alleviate the pathological damage of the gastric mucosa， thereby demonstrating a protective effect against CAG in mice.

Ethanol detection plays an important role in food industry,environmental monitoring,medical health monitoring,prevention of drunk driving,etc.The development of low-cost,high-performance ethanol sensors has important application value.In this study,a ZnO/FeS nano heterojunction ethanol sensor was prepared on commercial ceramic silver electrode substrate.The sensing characteristics of the sensor for ethanol gas were systematically studied.The results showed that ZnO had a nanowire structure,and the FeS was coated on the ZnO nanowire in the form of nanosheets.The sensor performed well for ethanol detection in environments with relative humidity ranging from 30%to 60%,with a detection range from 0.2 mg/m3 to 50 mg/m3.At the optimum operating temperature of 300℃,the response of ZnO/FeS nano heterojunction sensor to 50 mg/m3 ethanol was 15.6,the response time was 5.0 s,and the detection limit was as low as 0.101 mg/m3,which was obviously better than that of commercial ethanol sensor.This sensor was highly selective for ethanol compared to other gases such as CO,NH3,acetone,etc,and could steadily work for 30 days.The fabricated sensor had good development potential in the field of low-cost and high-performance ethanol gas detection.

Objective To establish a chromatography-tandem mass spectrometry method for detecting chlorfenapyr and its metabolite tralopyril in blood,and to investigate the toxicokinetics in rats.Methods Chlorfenapyr(8 mg/kg)was administered orally to rats,and blood samples were collected from rats'canthus vein at 5 min,15 min,30 min,1 h,3 h,6 h,12 h,24 h and 48 h after administration.The blood samples were extracted using 100 μL of 5%formic acid solution and 400 μL of acetonitrile.Chlorfena-pyr was qualitatively and quantitatively detected by triple quadrupole gas chromatography-tandem mass spectrometry(GC-MS/MS)and tralopyril was detected by triple quadrupole liquid chromatography-tandem mass spectrometry(LC-MS/MS).The DAS 3.0 software was used to fit the toxicokinetic equa-tions and calculate the toxicokinetic parameters.Results Chlorfenapyr was detectable from 5 min to 24 h with a peak time of 1 h.Tralopyril was detectable from 15 min to 48 h with a peak time of 3 h.The toxicokinetic process of chlorfenapyr in rat blood conformed to a first-order absorption one-compartment open model,with the toxicokinetic equation described as C=e-0.265t-e-0.175t.Tralopyril con-formed to the first-order absorption three-compartment model,and the toxicokinetic equation was C=47 361.069e-2.209t-35 404.962e-1.486t+11 956.363e-0.512t.In the equations,C stands for the concentration of the target substance in the blood,e is the natural constant(≈2.718 28),and t stands for time.Conclu-sion This study optimized the detection method for chlorfenapyr and its metabolite tralopyril in blood.The toxicokinetic equations and parameters of chlorfenapyr and tralopyril can provide a reference for the estimation of oral intake time of chlorfenapyr.

PURPOSE: To investigate the incidence and influencing factors of bone loss in patients with spinal cord injury (SCI). METHODS: A retrospective case-control study was conducted. Patients with SCI in our hospital from January 2019 to March 2023 were collected. According to the correlation between bone mineral density (BMD) at different sites, the patients were divided into the lumbar spine group and the hip joint group. According to the BMD value, the patients were divided into the normal bone mass group (t > -1.0 standard deviation) and the osteopenia group (t ≤ -1.0 standard deviation). The influencing factors accumulated as follows: gender, age, height, weight, cause of injury, injury segment, injury degree, time after injury, start time of rehabilitation, motor score, sensory score, spasticity, serum value of alkaline phosphatase, calcium, and phosphorus. The trend chart was drawn and the influencing factors were analyzed. SPSS 26.0 was used for statistical analysis. Correlation analysis was used to test the correlation between the BMD values of the lumbar spine and bilateral hips. Binary logistic regression analysis was used to explore the influencing factors of osteoporosis after SCI. p < 0.05 was considered statistically significant. RESULTS: The incidence of bone loss in patients with SCI was 66.3%. There was a low concordance between bone loss in the lumbar spine and the hip, and the hip was particularly susceptible to bone loss after SCI, with an upward trend in incidence (36% - 82%). In this study, patients with SCI were divided into the lumbar spine group (n = 100) and the hip group (n = 185) according to the BMD values of different sites. Then, the lumbar spine group was divided into the normal bone mass group (n = 53) and the osteopenia group (n = 47); the hip joint group was divided into the normal bone mass group (n = 83) and the osteopenia group (n = 102). Of these, lumbar bone loss after SCI is correlated with gender and weight (p = 0.032 and < 0.001, respectively), and hip bone loss is correlated with gender, height, weight, and time since injury (p < 0.001, p = 0.015, 0.009, and 0.012, respectively). CONCLUSIONS The incidence of bone loss after SCI was high, especially in the hip. The incidence and influencing factors of bone loss in the lumbar spine and hip were different. Patients with SCI who are male, low height, lightweight, and long time after injury were more likely to have bone loss.
Humans ; Spinal Cord Injuries/complications* ; Male ; Female ; Retrospective Studies ; Incidence ; Adult ; Bone Density ; Middle Aged ; Case-Control Studies ; Osteoporosis/etiology* ; Lumbar Vertebrae ; Bone Diseases, Metabolic/etiology* ; Aged ; Risk Factors

To guide clinical blood transfusion practices for pediatric patients, the National Health Commission has issued the health standard "Guideline for pediatric transfusion" (WS/T 795-2022). Blood transfusion is one of the most commonly used supportive treatments for children with hematological diseases. This guideline provides guidance and recommendations for blood transfusions in children with aplastic anemia, thalassemia, autoimmune hemolytic anemia, glucose-6-phosphate dehydrogenase deficiency, acute leukemia, myelodysplastic syndromes, immune thrombocytopenic purpura, and thrombotic thrombocytopenic purpura. This article presents the evidence and interpretation of the blood transfusion provisions for children with hematological diseases in the "Guideline for pediatric transfusion", aiming to assist in the understanding and implementing the blood transfusion section of this guideline.
Humans ; Child ; Hematologic Diseases/therapy* ; Blood Transfusion/standards* ; Practice Guidelines as Topic

To guide clinical blood transfusion practices for pediatric patients, the National Health Commission has issued the health standard "Guideline for pediatric transfusion" (WS/T 795-2022). Blood transfusion for children undergoing hematopoietic stem cell transplantation is highly complex and challenging. This guideline provides recommendations on transfusion thresholds and the selection of blood components for these children. This article presents the evidence and interpretation of the transfusion provisions for children undergoing hematopoietic stem cell transplantation, with the aim of enhancing the understanding and implementation of the "Guideline for pediatric transfusion".
Humans ; Hematopoietic Stem Cell Transplantation ; Child ; Blood Transfusion/standards* ; Practice Guidelines as Topic