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.

Parathyromegaly refers to chronic enlargement of the parathyroid glands caused by multiple etiological factors. Pathological conditions, such as hyperparathyroidism, parathyroid hyperfunction, parathyroid adenoma, parathyroid cysts, and parathyroid carcinoma may all lead to parathyromegaly. Notably, calcium intake insufficiency and/or vitamin D insufficiency (CVI), which is the predominant etiology of parathyromegaly, now has been recognized as a global public health challenge. Chronic CVI induces negative calcium balance and relative low serum calcium level, stimulating compensatory parathyroid hyperplasia and enlargement. This progression triggers parathyroid hyperfunction and secondary hyperparathyroidism, resulting in bone mass loss, height reduction, kyphosis, osteoporosis, pathological fractures, metastatic vascular calcification and systemic abnormal calcium migration and calcinosis (such as urolithiasis). During the early stages of parathyromegaly, the condition remains preventable and treatable; However, delayed intervention may lead to irreversible tertiary hyperparathyroidism. CVI-associated parathyromegaly exhibits high prevalence and heterogeneous clinical manifestations, representing a critically underrecognized clinical entity. This article will systematically discuss the etiology, pathological characteristics, clinical consequences, and prevention and control strategies for CVI-related parathyromegaly.

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.

This research aimed to comprehensively understand the prevalence of mutation in drug-resistant molecular markers of imported Plasmodium vivax in Chongqing,the Pvmdr1,Pvdhps,Pvdhfr,Pvcrt-o and Pvk12 genes of Plasmodium vivax were systematically analyzed.Blood samples were collected from imported Plasmodium vivax-infected patients in Chongqing between 2011 and 2022.The Pvmdr1,Pvdhps,Pvdhfr,Pvcrt-o,and Pvk12 genes were amplified and then sequenced to precisely evaluate gene mutations.Bioinformatics methods were employed to conduct in depth analysis of the mutation prevalence.Regarding the Pvdhfr gene,mutations at codons 50,57,58,61,99,117,and 199 were detected in 2.9%,23.5%,76.4%,23.53%,2.9%,82.3%,and 5.88%of the samples,respectively.The double-mutant haplotype S58R/S117N was the most prevalent,accounting for 50%,followed by the quadruple-mutant haplotype F57L/S58R/T61M/S117T,which accounted for 11.76%.Among the four types of tandem-repeat variations of Pvdhfr,the wild-type was the most common,and the insertion type was a novel discovery in this study.For the Pvdhps gene,the prevalence among mutation genotypes was relatively low.The single-mutant genotype was dominant,constituting 27.03%.The prevalence of Pvmdr1 mutations at codons 958 and 1076 was 100%and 89.19%,respectively.Among the 37 successfully sequenced samples,K10 insertion was detected in only 8 cases(22.22%).Notably,no non-synonymous mutations of Pvk12 were identified in this study.The cases in this study were imported from various countries of origin.Novel tandem-repeat variation tyres of Pvdhfr and new mutation sites of Pvdhps were identifide,thus enriching the mutation information of imported Plasmodium vivax resistance molecular markers in China.

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.

Genitourinary tract infections caused by Chlamydia trachomatis ( Ct) are characterized by their insidious onset, mild symptoms, and prolonged disease course, making them challenging to treat effectively. Chronic persistent infections and associated complications impose a significant burden on both patients and society. Numerous studies have shown that relying solely on antibiotics as first-line therapy may not be sufficient to completely eradicate urogenital Ct infections. Additionally, antibiotic use can lead to the development of Ct resistance and disrupt the body′s microbial balance. Therefore, the development of novel Ct inhibitors is crucial. This review summarizes recent advances in research on Ct inhibitors, aiming to provide a valuable reference for both basic research and clinical treatment of urogenital Ct infections.

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:To assess the effect of short-term exposures to atmospheric fine particulate matter (PM 2.5) and its components on cognitive function in middle-aged and older people aged 40-89 and identify key components that affect cognitive function. Methods:From October 2018 to March 2019, a cross-sectional survey of middle-aged and older people aged 40-89 was conducted across 10 cities in Beijing-Tianjin-Hebei and neighboring regions of China. Data on PM 2.5 and its components were collected from the nearest air supermonitoring stations to the residential addresses. The cognitive function was assessed using the Min-Mental State Examination (MMSE) scale. Multiple linear regression models were used to assess the effect of short-term exposures to PM 2.5 and its components on cognitive function in middle-aged and older people. The restricted cubic spline function was used to fit the exposure-response relationship between different components and changes in MMSE scores. Results:The age of the 1 978 respondents was (65.1±13.4) years, and 976 (49.34%) were males. During the study period, the daily mean concentration of PM 2.5 was (71.2±43.2) μg/m 3, and the MMSE score was (28.2±3.7). The results of the multiple linear regression model showed that short-term exposures to PM 2.5 and its components were associated with cognitive decline in middle-aged and older people after adjusting for confounding factors, and the effect was higher at lag 0-28 days. For an interquartile range (64.3 μg/m 3) increase in PM 2.5 at lag 0-28 d, the MMSE score decreased by 5.91 (95% CI: 0.04, 11.77). For an interquartile range increase in organic carbon (OC), antimony (Sb), chromium (Cr), zinc (Zn), tin (Sn), and cadmium (Cd), the MMSE scores of middle-aged and older people decreased by 5.71 (95% CI: 1.69, 9.73), 4.67 (95% CI: 2.50, 6.84), 4.49 (95% CI: 1.05, 7.92), 3.65 (95% CI: 0.89, 6.42), 2.76 (95% CI: 1.22, 4.30), and 1.72 (95% CI: 0.53, 2.92). Conclusions:Short-term exposures to atmospheric PM 2.5 and its components (OC, Sb, Cr, Zn, Sn, and Cd) are associated with cognitive decline in middle-aged and older people.