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.

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.

italic>Salvia apiana Jepson, commonly known as white sage, is a perennial sub-shrub of the Salvia genus in the Lamiaceae family with a long medicinal history. In this study, the complete chloroplast genome of S. apiana was sequenced using PacBio HiFi third-generation sequencing technology. The physical map of the genome was constructed, and the sequence structure features, codon preference, and repetitive sequences were analyzed. Furthermore, a comparative analysis of the chloroplast genome and phylogenetic evolution with closely related species within the same genus was conducted. The chloroplast genome of S. apiana was found to have a length of 151 701 bp (GenBank accession number: OR389048), with a typical quadripartite structure and a GC content of 38.06%. A total of 132 genes were annotated, including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Among them, 17 genes contained introns, and 18 genes were present in duplicate copies. Codon preference analysis revealed a preference for codons ending with A or U. Analysis of repetitive structures in the S. apiana chloroplast genome identified 170 simple sequence repeat (SSR) sites and 65 scattered repeat sequences, with the majority of SSR sites composed of A and T. Phylogenetic analysis of the complete chloroplast genomes of 21 species within the same genus showed that S. apiana is most closely related to Salvia hispanica Ettling. ex Willk. & Lange, Salvia leucantha Cav., and Salvia tiliifolia Vahl. Comparative analysis of the chloroplast genomes revealed slight contraction and expansion of the inverted repeat (IR) boundaries in S. apiana, as well as multiple highly variable regions in the chloroplast genome sequence. This study establishes a method for de novo assembling the chloroplast genome of S. apiana using third-generation sequencing data and provides a comprehensive analysis of its chloroplast genome, which can serve as a theoretical basis for studies on chloroplast genetic engineering, genetic diversity analysis, molecular breeding, and species identification.

Objective To study the pharmacokinetic characteristics of etoricoxib tablets in healthy Chinese subjects and to evaluate the bioequivalence and safety of the test and reference formulations.Methods In a randomised,single-dose,two-period,two-sequence crossover trial,28 healthy subjects were enrolled under the fasting and fed conditions,respectively,who received a single oral dose of 60 mg of etoricoxib tablets in the test or reference formulation.The concentration of etoricoxib in plasma was detected by LC-MS/MS,and the main pharmacokinetic parameters were calculated to evaluate bioequivalence and using WinNonlin 8.2 software.Results The main pharmacokinetic parameters of the test and reference preparations were as follows:The fasting condition Cmax of etoricoxib were(1 176.96±287.95)and(1 164.93±189.65)ng·mL-1;AUC0-t were(18 651.95±6 100.27)and(19 241.39±6 107.48)ng·h·mL-1;and AUC0-∞ were(19 939.15±7 553.27)and(20 536.31±7 223.40)ng·h·mL-1.The fed condition Cmax of etoricoxib were(913.50±184.72)and(878.59±164.35)ng·mL-1;and AUC0-t were(19 085.22±5 155.01)and(18 669.54±4 508.21)ng·h·mL-1;AUC0-∞ were(20 103.77±5 567.02)and(19 528.05±4 989.74)ng·h·mL-1.The 90％confidence intervals for the geometric mean ratios of the main pharmacokinetic parameters in the fasting and fed conditions fell between 80.00％and 125.00％.The incidence of adverse events in the fasting and fed conditions were 28.57％and 21.43％,respectively.Conclusion Two kinds of etoricoxib tablets are bioequivalent,and have similar safety in healthy Chinese subjects.

Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P＜0.05).After continuation treatment,the remission rate was 54.59％(202 cases/370 cases),and the recurrence rate was 6.49％(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35％(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.

Objective To establish an indirect enzyme-linked immunosorbent assay(ELISA)method for testing the concentration of a monoclonal antibody target tumor necrosis factor-α(TNF-α)in animal serum.Methods The critical parameters of the method including coating concentration of human TNF-α,source,concentration and stability of HRP-labeled goat anti-human immunoglobulin G(IgG)were investigated.The specificity,accuracy,precision,linearity and Limited of Determination of the method were investigated.Results The critical parameters of the method were confirmed as below:TNF-α was coated at 400 ng·mL-1;HRP labeled goat anti-human IgG antibody was diluted at 1:3.0 ×105;the diluted horseradish peroxidase labeled goat anti-human IgG antibody is well stored at 4 ℃ for 3 days.Meanwhile the method was confirmed to have good specificity,the recovery rate ranged from 84.00％to 106.82％,the coefficient of variation of different antibody concentration levels were no more than 10％;the method had a good linearity and the standard curve was y=(-8.37×103-2.37 × 106)/[1+(x/29.80)106]+2.37 × 106(R2=0.999);the limit of quantification was 1 ng·mL-1,all of which met the requirements.Conclusion A accurate and robust ELISA method was developed to test the concentration of anti-TNF-α monoclonal antibody in serum.

Objective To investigate the risk factors of in-hospital mortality and establish a risk prediction model for patients receiving venoarterial extracorporeal membrane oxygenation(VA-ECMO).Methods We retrospectively collected the data of 302 patients receiving VA-ECMO in ICU of 3 hospitals in Guangdong Province between January,2015 and January,2022 using a convenience sampling method.The patients were divided into a derivation cohort(201 cases)and a validation cohort(101 cases).Univariate and multivariate logistic regression analyses were used to analyze the risk factors for in-hospital death of these patients,based on which a risk prediction model was established in the form of a nomogram.The receiver operator characteristic(ROC)curve,calibration curve and clinical decision curve were used to evaluate the discrimination ability,calibration and clinical validity of this model.Results The in-hospital mortality risk prediction model was established based the risk factors including hypertension(OR=3.694,95%CI:1.582-8.621),continuous renal replacement therapy(OR=9.661,95%CI:4.103-22.745),elevated Na2+ level(OR=1.048,95%CI:1.003-1.095)and increased hemoglobin level(OR=0.987,95%CI:0.977-0.998).In the derivation cohort,the area under the ROC curve(AUC)of this model was 0.829(95%CI:0.770-0.889),greater than those of the 4 single factors(all AUC<0.800),APACHE Ⅱ Score(AUC=0.777,95%CI:0.714-0.840)and the SOFA Score(AUC=0.721,95%CI:0.647-0.796).The results of internal validation showed that the AUC of the model was 0.774(95%CI:0.679-0.869),and the goodness of fit test showed a good fitting of this model(χ2=4.629,P>0.05).Conclusion The risk prediction model for in-hospital mortality of patients on VA-ECMO has good differentiation,calibration and clinical effectiveness and outperforms the commonly used disease severity scoring system,and thus can be used for assessing disease severity and prognostic risk level in critically ill patients.