Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

This study aims to explore the scientific connotation of sinking Rehmanniae Radix has the best quality and compare the quality between floating and sinking fresh Rehmanniae Radix samples. Ultra-performance liquid chromatography tandem quadrupole electrostatic field Orbitrap high-resolution mass spectrometry(UHPLC-Q-Orbitrap HRMS) was employed to detect the chemical components in floating and sinking fresh Rehmanniae Radix samples. The fingerprint of fresh Rehmanniae Radix was established by high performance liquid chromatography(HPLC), and four index components were determined simultaneously. The cluster analysis, principal component analysis(PCA), and orthogonal partial least squares-discriminant analysis(OPLS-DA) were conducted to compare the quality of floating and sinking fresh Rehmanniae Radix samples. An evaporative light-scattering detector was used to compare the content of five sugars. The extract yield and drying rate were determined, and the quality connotation of sinking Rehmanniae Radix has the best quality was explained by multiple indicators. A total of 41 components were preliminarily identified from fresh Rehmanniae Radix by UHPLC-Q-Orbitrap HRMS, including 7 iridoid glycosides, 9 phenylethanol glycosides, 6 amino acids, 4 sugars, 3 phenolic acids, 5 nucleosides, 3 organic acids, 1 ionone, 1 furan, 1 coumarin, and 1 phenylpropanoid. The results showed that the main chemical components were consistent between floating and sinking fresh Rehmanniae Radix. Nine common peaks were identified in the fingerprints of 15 batches of floating and sinking fresh Rehmanniae Radix samples, and the similarity of fingerprints was greater than 0.9. The cluster analysis, PCA, and OPLS-DA classified floating and sinking fresh Rehmanniae Radix sasmples into two categories, indicating differences in the quality between them. The total content of catalpol, rehmannioside D, ajugol, and verbascoside in sinking fresh Rehmanniae Radix samples was higher than that in floating samples of the same batch and specification, and the main differential component was catalpol. The total content of fructose, glucose, sucrose, raffinose, and stachyose in sinking fresh Rehmanniae Radix samples was higher than that in floating samples of the same batch and specification, and the main differential component was stachyose. The extract yield and drying rate of the sinking samples were higher than those of floating samples. This study preliminarily showed that floating and sinking fresh Rehmanniae Radix samples had the same components but great differences in the content of medicinal substance basis. The total content of four glycosides and five sugars, extract yield, and drying rate of sinking fresh Rehmanniae Radix samples is higher than that of floating samples of the same batch and specification. These findings, to a certain extent, explains the scientificity of sinking Rehmanniae Radix has the best quality recorded in ancient books and provide a reference for the quality control and clinical application of fresh Rehmanniae Radix.
Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Rehmannia/chemistry* ; Chemometrics ; Mass Spectrometry/methods* ; Quality Control ; Principal Component Analysis ; Plant Extracts

Diabetic foot (DF) is one of the most serious chronic complications of diabetes. The incidence rate among global diabetes patients is as high as 15% to 25%, and about 50% of patients will develop contralateral foot ulcers within 5 years after the first unilateral ulcer. As a non-invasive prevention and control solution, the application progress of functional insoles is mainly reflected in the following aspects:(1) Material innovation. The application of new composite materials and smart materials has significantly enhanced the pressure reduction effect and comfort. (2) Structural optimization. The development of multi-layer design and local pressure reduction structure has achieved more precise pressure distribution regulation. (3) Manufacturing process. 3D printing and parametric design have enabled the personalized customization of functional insoles. (4) Intelligent monitoring. It integrates functions such as pressure sensing and temperature monitoring, achieving real-time monitoring and early warning of foot conditions. Clinical research has confirmed that personalized functional insoles could reduce the incidence of foot ulcers and shorten the healing time of ulcers. At present, the research hotspots mainly focus on the development of smart materials, the construction of multi-functional integration and remote monitoring systems. However, in-depth research is still needed in the aspects of biomechanical mechanisms, standardized evaluation systems and long-term efficacy assessment. The development of future functional insoles should focus on the coordinated advancement of "personalization-intelligence-standardization", with the aim of providing more effective solutions for the prevention and treatment of DF.
Humans ; Diabetic Foot/therapy* ; Foot Orthoses

OBJECTIVE: To investigate the therapeutic potential of pseudolaric acid B (PAB) on non-alcoholic fatty liver disease (NAFLD) and its underlying molecular mechanism in vitro and in vivo. METHODS: Eight-week-old male C57BL/6J mice (n=32) were fed either a normal chow diet (NCD) or a high-fat diet (HFD) for 8 weeks. The HFD mice were divided into 3 groups according to a simple random method, including HFD, PAB low-dose [10 mg/(kg·d), PAB-L], and PAB high-dose [20 mg/(kg·d), PAB-H] groups. After 8 weeks of treatment, glucose metabolism and insulin resistance were assessed by oral glucose tolerance test (OGTT) and insulin tolerance test (ITT). Biochemical assays were used to measure the serum and cellular levels of total cholesterol (TC), triglycerides (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). White adipose tissue (WAT), brown adipose tissue (BAT) and liver tissue were subjected to hematoxylin and eosin (H&E) staining or Oil Red O staining to observe the alterations in adipose tissue and liver injury. PharmMapper and DisGeNet were used to predict the NAFLD-related PAB targets. Peroxisome proliferator-activated receptor alpha (PPARα) pathway involvement was suggested by Kyoto Encyclopedia of Genes and Genomes (KEGG) and search tool Retrieval of Interacting Genes (STRING) analyses. Luciferase reporter assay, cellular thermal shift assay (CETSA), and drug affinity responsive target stability assay (DARTS) were conducted to confirm direct binding of PAB with PPARα. Molecular dynamics simulations were applied to further validate target engagement. RT-qPCR and Western blot were performed to assess the downstream genes and proteins expression, and validated by PPARα inhibitor MK886. RESULTS: PAB significantly reduced serum TC, TG, LDL-C, AST, and ALT levels, and increased HDL-C level in HFD mice (P<0.01). Target prediction analysis indicated a significant correlation between PAB and PPARα pathway. PAB direct target binding with PPARα was confirmed through luciferase reporter assay, CETSA, and DARTS (P<0.05 or P<0.01). The target engagement between PAB and PPARα protein was further confirmed by molecular dynamics simulations and the top 3 amino acid residues, LEU321, MET355, and PHE273 showed the most significant changes in mutational energy. Subsequently, PAB upregulated the genes expressions involved in lipid metabolism and mitochondrial biogenesis downstream of PPARα (P<0.05 or P<0.01). Significantly, the PPARα inhibitor MK886 effectively reversed the lipid-lowering and PPARα activation properties of PAB (P<0.05 or P<0.01). CONCLUSION PAB mitigates lipid accumulation, ameliorates liver damage, and improves mitochondrial biogenesis by binding with PPARα, thus presenting a potential candidate for pharmaceutical development in the treatment of NAFLD.
Animals ; PPAR alpha/metabolism* ; Non-alcoholic Fatty Liver Disease/pathology* ; Male ; Mice, Inbred C57BL ; Lipid Metabolism/drug effects* ; Diterpenes/therapeutic use* ; Organelle Biogenesis ; Diet, High-Fat ; Humans ; Mice ; Liver/metabolism* ; Insulin Resistance ; Mitochondria/metabolism* ; Molecular Docking Simulation

Objective To summarize the acupoints and parameters commonly used in the treatment of vascular cognitive impairment(VCI)by electro-acupuncture(EA)through the visual data mining technique to provide a reference basis for clinical treatment.Methods The clinical studies of EA on the treatment of VCI were searched in CNKI,Wanfang,VIP,CBM,PubMed,Embase,Cochrane Library,web of science and other major databases.The literature is managed by Note Express and the database is established by Excel.The frequency of selected acupoints,frequency,meridian tropism,parameter frequency and frequency of used acupoints are counted.Factor analysis is carried out by SPSS 21.0 software.SPSS Modeler 18.3 software is used to analyze association rules and co-occurrence network,and the analysis results are visualized by Cytoscape 3.9.1 software.Results Finally,155 papers were included,containing 155 acupoint prescriptions and 157 parameter prescriptions.Acupoint prescriptions involved 100 acupoints with a total frequency of 856 times;parameter prescriptions involved 33 parameters with a total frequency of 788 times.Conclusion At present,there is a big difference between the clinical studies,and there is no recognized acupoint and parameter for EA treatment of VCI.By further summarizing the law of EA acupuncture point and parameter,the study has sorted out the law of commonly used acupoints,meridian tropism,compounding and parameter selection for EA treatment of VCI.It was concluded that the selection of acupoints mainly started from the three aspects of deficiency,phlegm and stasis,focusing on the combination of local and distal selection of acupoints,through the identification of internal organs and meridians,to achieve the simultaneous regulation of the heart,spleen and kidney,and to take into account both the symptoms and the root cause,and to play the roles of opening the orifices to wake up mind,calming mind and benefiting intellect,strengthening the spleen and tonifying the kidneys,and invigorating blood circulation to remove stasis.The parameters of EA are recommended to be sparse and dense wave,low frequency,as tolerated by the patient,30 minutes/times,1 time/day,5 times/week as the main combinations,which can provide a certain reference basis for clinical decision-making.

Objective To explore the construction and visualization for knowledge graph of Ling Shu(Spiritual Pivot),with a view to providing ideas for the structured storage and display of the theoretical knowledge of the ancient Chinese medical books.Methods Using the professional idea of constructing knowledge graphs for reference,text mining technology was applied to construct the thesaurus,and then word division,entity recognition,and relationship extraction for the original text of Ling Shu were performed to get the elements of knowledge graph construction.The graph database Neo4j was used for the storage and query of the knowledge graph,and then the visual display of the knowledge graph was achieved.Results The 1 216 high-quality words consisting of the thesaurus of Ling Shu were obtained,and the construction of the knowledge graph of the theory of Ling Shu was realized.The constructed knowledge graph basically displayed the traditional Chinese medicine theories such as the correlation of visceral manifestations with essence qi,and the relationship between emotions and the five-zang organs described in Ling Shu,which made the retrieval and utilization of the related entities and relationships possible,and provided ideas for the structured storage and display of the theoretical knowledge of the ancient books of Chinese medicine.Conclusion The knowledge graph construction technology can be used to obtain the Chinese medicine theoretical knowledge graph of Ling Shu,and to display the knowledge connections of yin-yang and the five elements,and the internal organs and meridians expressed in the Ling Shu.The construction of the knowledge graph and its storage in the graph database enable the knowledge graph involved in the text of Ling Shu to be displayed in the form of visualized semantic network graph,and also make the embedding of other search systems such as the semantic search and semantic wiki possible,which will be helpful for the development of Chinese medicine intelligent medical services.

Objective:To determine the erythromycin resistance of Bordetella pertussis isolates and their ptxP1 and ptxP3 phenotypic composition and compare clinical manifestations of children with pertussis caused by the two types of strains. Methods:This was a cross-sectional study, the pertussis cases diagnosed using bacterial culture from January 2019 to December 2022 in Beijing Children′s Hospital and the First People′s Hospital of Wuhu were collected.Any suspected Bordetella pertussis colonies were identified by the slide agglutination test.The susceptibility of isolates to erythromycin was detected by the E-test and K-B test.The ptxP gene was amplified by polymerase chain reaction and sequenced to determine its genotype. t-test, Mann-Whitney U-test, Chi-square test and Fisher′s exact test were use to statistical analysis. Results:A total of 192 strains of Bordetella pertussis were identified, including 188 (97.9%) erythromycin-resistant strains.Among the 188 strains, 30.3%(57/188) belonged to the ptxP1 genotype and 69.7%(131/188) belonged to the ptxP3 genotype.In children aged below 1 year old, the incidence of paroxysmal cough caused by infection with the ptxP3 strain was higher than that with the ptxP1 strain (57.1% vs.29.4%, P<0.05), and children infected with the ptxP3 strain were more likely to develop apnea or asphyxia (23.8% vs.17.6%), post-tussive vomiting (44.4% vs.32.4%), whooping cough (72.0% vs.50.0%) and pneumonia or bronchitis (85.7% vs.73.5%) compared to those infected with the ptxP1 strain, but the differences were not statistically significant(all P>0.05). In children aged 1 year old and above, the white blood cell count of children infected with the ptxP1 strain was higher than that of infections with the ptxP3 strain [13.5(9.9, 24.5)×10 9/L, 10.3 (7.0, 16.4)×10 9/L, P<0.05], and children infected with the ptxP1 strain were more likely to contract other pathogen infections than those infected with the ptxP3 strain (17.4% vs.4.4%, P>0.05). Conclusions:ptxP3 erythromycin-resistant Bordetella pertussis has become the main pathogen of pertussis.Infants with pertussis caused by the ptxP3 erythromycin-resistant strain show more significant manifestations and a higher possibility of severe symptoms than those infected with the ptxP1 erythromycin-resistant strain.

Objective:To investigate the regulatory effect of transient receptor potential cation channel subfamily C member 3 (TRPC3) on the retina in oxygen-induced retinopathy (OIR) mice and biological behavior of human retinal vascular endothelial cells (HREC).Methods:A total of 32 healthy SPF grade 7-day-old C57BL/6 mice were selected and randomly divided into a control group and an OIR group by the random number table method, with 16 mice in each group.The control group received no special treatment, and the OIR model was established in the OIR group.On postnatal day 17 (PN17), the success of the model establishment was verified by immunofluorescence staining of the retinal patch.The in vitro cultured HREC were divided into a normal control group, a transfection reagent group, and a si-TRPC3 group.The normal control group received no special treatment, while the transfection reagent group and the si-TRPC3 group were transfected with transfection reagent or transfection reagent + si-TRPC3.The relative expression of TRPC3 mRNA was detected by real-time quantitative fluorescence PCR.The relative expressions of TRPC3, transcription factor NF-E2 related factor (Nrf2), and superoxide dismutase (SOD) proteins were determined by Western blot.HREC were further divided into a normal control group, a vascular endothelial growth factor (VEGF) group, a si-TRPC3 group, and a Pyr3 (TRPC3 channel inhibitor) group, which were cultured in complete medium, medium containing 20 ng/ml VEGF recombinant protein, medium containing 20 ng/ml VEGF recombinant protein (si-TRPC3 transfection for 72 hours), and medium containing 20 ng/ml VEGF recombinant protein+ 1 μmol/L Pyr3 for 48 hours, respectively.The proliferation ability of HREC was detected using cell counting kit 8 (CCK-8). The horizontal and vertical migration ability of cells were detected by cell scratch assay and transwell assay, respectively.This study followed the 3R principles of animal welfare and was approved by the Ethics Committee of Hebei Eye Hospital (No.2023LW04). Results:Pathological neovascular clusters with strong fluorescent staining appeared in the retina of OIR mice on PN17.The relative expressions of TRPC3 mRNA and protein in the retina of OIR mice were 2.057±0.244 and 1.517±0.290, respectively, significantly higher than 0.983±0.033 and 0.874±0.052 of control group ( t=6.165, 3.094; both at P<0.05). The relative expression levels of TRPC3 mRNA and protein were significantly lower, and the relative expression levels of Nrf2 and SOD proteins were higher in the si-TRPC3 group than in the normal control and transfection reagent groups, and the differences were statistically significant (all at P<0.05). The CCK-8 experiment results showed that the cell absorbance value was higher in the VEGF group than in the normal control group, and lower in the si-TRPC3 and Pyr3 groups than in the VEGF group, with statistically significant differences (all at P<0.05). The results of the cell scratch experiment showed that the lateral migration rate of VEGF group cells was higher than that of normal control group, while the lateral migration rate of si-TRPC3 group and Pyr3 group cells was lower than that of VEGF group, and the differences were statistically significant (all at P<0.05). The transwell experiment results showed that the number of stained cells in the VEGF group was higher than that in the normal control group, and the number of stained cells in the si-TRPC3 group and Pyr3 group was lower than that in the VEGF group, with statistically significant differences (all at P<0.05). Conclusions:Hypoxia induces increased TRPC3 expression in OIR mouse retina, and downregulation of TRPC3 inhibits HREC proliferation and migration.The mechanism is related to the activation of the Nrf2-related oxidative stress pathway.