OBJECTIVE To investigate the apoptosis-inducing effect of esculetin （Esc） on acute myeloid leukemia （AML） HL-60 cells by regulating the protein kinase B （AKT）/S-phase kinase-associated protein 2 （SKP2）/MutT homolog 1 （MTH1） pathway. METHODS AML HL-60 cells were randomly divided into control group （routine culture）， Esc low-concentration group （L-Esc group， 25 μmol/L Esc）， Esc medium-concentration group （M-Esc group， 50 μmol/L Esc）， Esc high-concentration group （H-Esc group， 100 μmol/L Esc）， and high-concentration of Esc+ SC79 （AKT agonist） group （100 μmol/L Esc+5 μmol/L SC79）. Cell proliferation in each group was detected by MTT assay and colony formation assay. The level of reactive oxygen species （ROS） in cells was measured by using the CM-H2DCFDA fluorescent probe. Cell apoptosis was analyzed by flow cytometry. Western blot assay was performed to detect the expression levels of apoptosis-related proteins [B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， cleaved caspase-3]， AKT/SKP2/MTH1 pathway-related proteins （p-AKT， AKT， SKP2， MTH1）， along with the upstream and downstream proteins of AKT phosphatidylinositol 3-kinase （PI3K）， cyclin-dependent kinase inhibitor 1 （P21） and cyclin-dependent kinase inhibitor 1B （P27）. RESULTS Compared with control group， the cell viability， colony number， and the phosphorylation levels of AKT and PI3K proteins as well as protein expressions of SKP2， MTH1 and Bcl-2 were significantly decreased （P＜0.05）， while ROS level， apoptosis rate， and the expression levels of Bax， cleaved caspase-3， P21 and P27 proteins were significantly increased （P＜0.05）. Moreover， the effects of Esc exhibited concentration-dependence （P＜0.05）. Compared with H-Esc group， above indexes of high-concentration of Esc+ SC79 group were reversed significantly （P＜0.05）. CONCLUSIONS Esc may promote massive ROS production and induce activation of apoptosis in HL-60 cells by inhibiting the AKT/SKP2/MTH1 pathway， thus inhibiting the proliferation of HL-60 cells.

Objective To establish an oxidative stress mouse model of atopic dermatitis (AD) by applying 2,4-dinitrofluorobenzene (DNFB) to the back and post-auricular skin of KM mice, and to evaluate the regulatory role of the RAGE-NLRP3 axis (receptor for advanced glycation end products-NOD-like receptor family, pyrin domain containing 3 axis) in AD-related oxidative stress, thereby providing a potential therapeutic target for AD treatment. Methods Twenty SPF-grade female KM mice were randomly divided into a control group (Control group) and an experimental group (DNFB group), with 10 mice in each group. Mice in the Control group were treated with an acetone-olive oil vehicle (acetone: olive oil = 3:1) on their back and post-auricular skin. Mice in the DNFB group were treated with 0.5% DNFB (prepared by adding 0.5 g DNFB per 100 mL of acetone-olive oil vehicle) on the same areas, once daily for 14 consecutive days. The severity of skin lesions was scored on days 2, 4, 6, 9, 12, and 14 of treatment. On day 14, scratching behavior and ear thickness were evaluated. Ear swelling was evaluated on the final day by measuring bilateral ear thickness three times with a vernier caliper; the three measurements were averaged. HE staining was used to observe morphological and structural changes of cells in the back skin tissues. The mRNA and protein expression levels of RAGE (receptor for advanced glycation end products) in skin tissues were detected by quantitative real-time PCR, Western blot, and immunohistochemical staining. The mRNA expression levels of oxidative stress-related molecules, including NLRP3 (NOD-like receptor family, pyrin domain containing 3), caspase-1 (cysteine-dependent aspartate-specific protease 1), and IL-1β (Interleukin-1β), were detected by quantitative real-time PCR. Results On day 14, the back skin lesion scores of the Control group and DNFB group were (0.20±0.42) and (9.93±1.30) (P<0.000 1), respectively. Scratching behavior scores were (5.00±2.05) and (49.26±8.49) episodes, respectively (P<0.000 1), and ear thicknesses were (213.00±11.87) μm and (765.93±140.47) μm (P<0.000 1), respectively. The DNFB group exhibited marked skin dryness, desquamation, and thickening. HE staining results showed that skin inflammation was obvious in the DNFB group, consistent with the pathological features of AD. Quantitative real-time PCR and Western blot results showed that compared with the Control group, the mRNA expression level of RAGE in skin tissues of the DNFB group was significantly increased (P<0.05), and the protein expression level of RAGE was also significantly increased (P<0.01). Immunohistochemical staining results showed that compared with the Control group, skin tissue sections of the DNFB group exhibited thickened stratum corneum and fibrotic proliferation of fibroblasts in the interstitium under microscopic observation, with a significant increase in RAGE protein expression in the skin tissues (P<0.01). Quantitative real-time PCR results showed that the mRNA expression levels of NLRP3, caspase-1, and IL-1β in skin tissues of the DNFB group were all significantly increased (P<0.01). Conclusion The AD mouse oxidative stress model has been successfully established by topical DNFB application. RAGE may promote the development of AD by regulating the NLRP3 inflammasome and IL-1β release, forming an oxidative-inflammatory cascade, suggesting that it could be a potential therapeutic target for AD.

Objective: To develop a convenient, direct, and highly sensitive method for screening trace chemical additives in complex Chinese patent medicines, thereby addressing core technological bottlenecks in pharmaceutical analysis and quality control. Methods: A brush ionization probe device was independently designed and constructed, and an efficient detection method was established through systematic optimization of key parameters. Twenty-three Chinese patent medicine samples, representing 6 dosage forms (capsules, tablets, pills, granules, powders, and liquid preparations), were analyzed using 10 common chemical additives as target analytes. Results: All samples were successfully analyzed without complex pretreatment, and 5 chemical additives were detected in 7 Chinese patent medicines. The brush ionization probe device exhibited cost-effectiveness (~0.2 USD per probe), operational simplicity, rapid analysis (~10s per sample), high efficiency, and minimal reagent consumption (~10 μL per sample). Conclusion: This advancement is expected to provide an innovative scientific tool for improving the generality and convenience of on-site quality control, while promoting technological progress in disciplines such as pharmacology and traditional Chinese medicine.

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.

OBJECTIVE To formulate the Expert Consensus on the Management of Radiopharmaceuticals in Medical Institutions （hereinafter referred to as “the Consensus”）， focusing on key aspects such as the procurement of radiopharmaceuticals， the management of self-made radiopharmaceutical preparations， standardized clinical application， and patient medication safety management， so as to provide a reference for improving the whole-process management of radiopharmaceuticals in medical institutions.METHODS The Consensus was initiated by the Chinese Society of Nuclear Medicine， the Clinical Pharmacy Professional Committee of the China Anti-Cancer Association， and the Committee of Integrative Oncology Pharmacy of the China Anti-Cancer Association. Organized by the consensus drafting group more than 90 experts from the fields of nuclear medicine， nuclear pharmacy， and pharmacy science across China were involved. The Consensus was developed through systematic review of relevant laws， regulations， policy documents， and existing experience in radiopharmaceutical management， followed by extensive discussion and deliberation to finalize the consensus. RESULTS &CONCLUSIONS The Consensus establishes 10 key points for whole-process management of radiopharmaceuticals in medical institutions， covering organizational management and personnel requirements， procurement， preparation， acceptance， storage， risk prevention and control during use， radiation protection， and waste disposal. The Consensus provides a reference for improving radiopharmaceutical management in medical institutions and for ensuring their efficacy and safety in clinical application.

In modern society, sugary foods have become an integral part of many people′s lives. However, excessive sugar consumption has adverse effects on both overall health and oral health, serving as a contributing factor to the global increasing incidence in oral diseases, cardiovascular diseases, cancers, obesity, and diabetes. In response to the health risks related to high-sugar diets, the World Health Organization (WHO) and World Dental Federation (FDI) have proposed initiatives and recommendations, with various governments implementing different policies and strategies to reduce sugar intake. Chinese government has also taken proactive measures. The "Healthy China Action (2019-2030)" initiative introduced by the State Council in 2019 established a crucial benchmark in limiting the average daily intake of added sugar to 25 g per person forward to 2030. Experts from Chinese Center for Disease Control and Prevention and the field of oral health have meticulously examined the impacts of sugar reduction on oral health, as well as strategies, methods, and practical considerations related to reducing sugar intake through several meeting and wrote the "Expert consensus: reducing free-sugar for caries prevention", which was subsequently reviewed and revised based on the feedback from multiple stakeholders. They have conducted thorough analyses of global trends in sugar reduction and best practices to provide valuable insights to China for crafting effective policies and strategies on sugar reduction. This consensus mainly includes the classification of free sugars, the latest scientific evidence on dental caries, recommendations from WHO on sugar-sweetened beverage taxes, nutrition labeling, advertising, food reform, adjusting supply systems, education, and promotion strategies, as well as sugar reduction actions taken by various governments around the world. Combining the actual situation in China, policy recommendations and authoritative popular science knowledge on sugar reduction for caries prevention to public are proposed to advocate for experts in multiple fields to focus on sugar reduction for caries prevention, promote the work process, and provide the scientific basis for oral health educators.

Objective:To investigate the effect of transforming growth factor beta 1 (TGF-β1) on the biological activity of infantile hemangioma (IH) -derived endothelial cells (HemECs) .Methods:Three proliferating IH tissues and three involuting IH tissues were collected from IH patients receiving surgical resection at the Department of Pediatric Surgery, West China Hospital, Sichuan University from February to August 2021. Primary HemECs were isolated from proliferating IH tissues, and human umbilical vein endothelial cells (HUVECs) served as the control. The TGF-β1 expression levels in tissues and cells were detected by immunohistochemical study and Western blot analysis. Cell counting kit-8 (CCK8) assay was performed to assess the effect of 0 (control group) - 100 ng/ml TGF-β1 on HemEC proliferation. HemECs were treated with 5 ng/ml TGF-β1 or without (control group), and after several hours of treatment, Transwell assay was performed to evaluate cell migration ability, and immunofluorescence assay to assess the changes in the expression of endothelial markers (platelet-endothelial cell adhesion molecule-1 [CD31], vascular endothelial cadherin [VE-cadherin]) and mesenchymal markers (α-smooth muscle actin [α-SMA], collagen type Ⅰ α 1 [COL1A1]). Comparisons between groups were conducted by t test or one-way analysis of variance. Results:Immunohistochemical study showed that proliferating IH tissues were stained positively for TGF-β1, which was expressed relatively abundantly; the percentages of TGF-β1-positive signal area were higher in the proliferating IH tissues (24.68% ± 3.74%) than in the involuting IH tissues (almost no expression). Western blot analysis revealed that the relative expression level of TGF-β1 was significantly higher in HemECs (1.08 ± 0.13) than in HUVECs (0.30 ± 0.04, t = 9.93, P < 0.001). CCK8 assay showed increased proliferative activity of HemECs in the 3.125-, 6.25-, 12.5-, 25-, 50- and 75-ng/ml TGF-β1 groups compared with the control group (all P < 0.05), and no significant difference was found between the 100-ng/ml TGF-β1 group and the control group ( P > 0.05). Transwell assay revealed an increased number of migratory HemECs in the 5-ng/ml TGF-β1 group (127 ± 6) compared with the control group (103 ± 9; t = 5.32, P < 0.01). Immunofluorescence assay showed significantly decreased fluorescence intensity of endothelial markers CD31 and VE-cadherin in the 5-ng/ml TGF-β1 group (5.441 ± 1.254, 5.073 ± 0.412, respectively) compared with the control group (9.518 ± 1.728,7.671 ± 0.921, t = 3.31, 4.46, P = 0.030, 0.011, respectively), and significantly increased fluorescence intensity of mesenchymal markers α-SMA and COL1A1 in the 5-ng/ml TGF-β1 group (8.074 ± 0.846, 5.885 ± 0.216, respectively) compared with the control group (0.393 ± 0.342, 0.295 ± 0.125, t = 14.58, 38.76, P < 0.001, < 0.000 1, respectively) . Conclusion:TGF-β1 was relatively highly expressed in the proliferating IH tissues and HemECs, and could promote the proliferation, migration and endothelial-to-mesenchymal transition of HemECs.

Objective:To investigate the acute effects of persistent high exposure to atmospheric fine particulate matter (PM 2.5) on residents' outpatient visits for respiratory diseases. Methods:We collected daily outpatient records from 92 hospitals in 13 cities across the Beijing-Tianjin-Hebei region, along with daily PM 2.5, nitrogen dioxide (NO 2), and meteorological data from 2013 to 2018. Five persistent high PM 2.5 exposure scenarios were defined in terms of daily mean PM 2.5 concentrations (>75 μg/m 3 and >150 μg/m 3), duration (≥2 days and ≥3 days), and whether or not there was concurrent exposure to high levels of NO 2 (daily mean NO 2 concentration >50 μg/m 3). A two-stage statistical analysis strategy based on a generalized linear model was applied to conduct a time-series analysis to assess the exposure-response relationship between persistent high PM 2.5 exposure scenarios and residents' outpatient visits for a variety of respiratory diseases, and to estimate excess outpatient visits. Results:During the period, M ( Q1, Q3) PM 2.5 and NO 2 concentrations were 61.2 (42.3, 95.1) μg/m 3 and 40.2 (31.4, 54.4) μg/m 3, respectively, and the daily respiratory disease outpatient visits were 57 (52, 66) cases. When compared with non-permanent high PM 2.5 exposure periods, exposure scenarios with PM 2.5 >75 μg/m 3 and lasting for ≥2 days caused an increased risk of outpatient visits for respiratory diseases by 2.10% (95% CI: 1.44%-2.77%), and resulted in 43 787 (95% CI: 30 025-57 757) excess visits; in this scenario, the concurrent exposure to high levels of NO 2 had a greater acute effect on respiratory disease visits than the absence of exposure to high levels of NO 2 ( P<0.001). The risk of respiratory disease visits increased substantially by 4.41% (95% CI: 3.15%-5.68%) when the daily mean PM 2.5 concentration exceeded 150 μg/m 3 for ≥2 days. Subgroup disease analyses showed that scenarios with daily mean PM 2.5 concentrations exceeding 75 μg/m 3 for ≥3 days caused a significant increase in the risk of lower respiratory tract infections, chronic lower respiratory disease, and asthma visits. Conclusions:Sustained persistent high PM 2.5 exposure increases the risk of outpatient visits for various respiratory diseases; concurrent exposure to high concentrations of NO 2 leads to a greater risk of visiting the clinic, suggesting that the prevention and control of PM 2.5 pollution should be synchronized with the control of mobile source emissions, to synergistically manage the compound pollution of PM 2.5 and NO 2 in the atmosphere.

Objective:An in vivo mammalian hepatocyte Unscheduled DNA Synthesis(UDS)test was used to evaluate the genotoxicity of Cross-linked Sodium Hyaluronate Gel and Bone Repair Materials,providing experimental evidence for establishing a UDS testing method for medical devices and materials.Methods:0.9％sodium chloride injection and cottonseed oil were used as the solvent for test materials and negative control,respectively.N-dimethylnitrosamine(NDMA)was used as the positive control for the early sampling times,and 2-acetylaminofluorene(2-AAF)was used as the positive control for the late sampling times.SD rats were administered a single dose for toxic exposure,and liver tissues were collected at 4 h and 16 h,respectively.Hepatocytes were isolated using collagenase perfusion.After labeling with 5-ethynyl-2'-deoxyuridine(EdU),and the net average fluorescence intensity(NAFI)of cell nuclei and nucleoplasm was measured by fluorescence microscope.Data from 50 cells were used to analyze the DNA repair level.Results:Compared with the negative control groups,the positive control groups(NDMA and 2-AAF)showed highly statistically significant differences in NAFI(P＜0.01),indicating successful induction of DNA damage.There was no statistically significant differences between the cross-linked sodium hyaluronate gel groups,bone repair material groups and the negative control group(P＞0.05),suggesting that these materials did not significantly induce DNA damage under the experimental conditions.Conclusion:This study first applied EdU labeling technology to the in vivo hepatic UDS assay,achieving non-radioactive labeling through click chemistry reactions.Under the conditions of this study,cross-linked sodium hyaluronate gel and bone repair materials did not exhibit genotoxicity.In the follow-up,the sample range can be expanded and the observation period can be prolonged to further improve the genotoxicity evaluation system of medical devices.

Objective:To evaluate the mediating effect of electrocardiographic (ECG) indicators in the association between short-term exposure to fine particulate matter (PM 2.5) and blood pressure and to explore the key PM 2.5 element constituents that produce the mediating effect. Methods:Based on a cross-sectional survey across 10 cities in the Beijing-Tianjin-Hebei region and surrounding areas, PM 2.5 and its element constituents were collected from the nearest air monitoring superstation. Blood pressure and ECG indicators of participants were obtained through physical examinations. A multivariate linear regression was used to evaluate the effect of short-term exposures to PM 2.5 on blood pressure. A mediation analysis was used to identify the mediating effect of ECG indicators in the association between exposure to PM 2.5 and its element constituents and blood pressure. Results:The age of the 1 793 participants was (65.1±13.3) years, and 885 (49.4%) were males. During the study period, the daily mean concentration of PM 2.5 was (70±45) μg/m 3, and the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP) were (139±20), (82±11), (101±13), and (57±17) mmHg (1 mmHg=0.133 kPa), respectively. The results of the multivariate linear regression showed that for every 10 μg/m 3 increase in PM 2.5 on the same day (lag 0), DBP increased by 0.15 (95% CI: 0.02-0.28) mmHg, and PP decreased 0.18 (95% CI: 0.36-0.01) mmHg. The exposure to 14 elemental constituents, such as Ga, Co and Se, was associated with an increase in DBP, while the exposure to 17 elemental constituents, such as Cs, Se and Ag, was associated with a decrease in PP. At lag 0, the PM 2.5-induced increase in DBP was mediated by the QRS interval (mediation percentage of 18.98%), and the PM 2.5-induced decrease in PP was mediated by the QT interval (mediation percentage of -6.31%). The exposure to K, Br, Pb, Zn, Ca, Co, Pd, Cu, and As constituents was associated with increases in DBP mediated by prolonged QRS interval. The exposure to Pb, Zn, K, and As constituents was associated with decreases in PP mediated by prolonged QRS interval. Conclusion:ECG indicators such as QRS interval may mediate the association between short-term exposure to PM 2.5 and its element constituents and blood pressure.