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.

Human physiological indicators have become an important standard for assessing health in modern society.Traditional detection methods often require a separate laboratory,complex operation process and long detection time,so it is urgent to develop portable,fast and accurate on-site detection technologies for bioanalysis.Point-of-care testing(POCT),which differs from traditional laboratory testing,can realize the rapid in situ detection of biomarkers without the complicated analytical process of the laboratory.Smartphones,which are an essential tool in our daily life,not only have independent operating systems and built-in storage functions,but also have high-definition cameras,which have great application potential in POCT visualization.The combination of various biosensing technologies and smartphones has developed into a new direction in the field of POCT.This review mainly introduced the research progress of smartphone-based visual biosensors in POCT in recent years,including colorimetric sensors,fluorescence sensors,chemiluminescence sensors and electrochemiluminescence sensors.Finally,the problems faced by smart-phone-based visual biosensors in the application of POCT were summarized,and their future development was prospected.

Objective To investigate the rate of germline variants in patients with pancreatic cancer and clinical characteristics related with germline variants.Methods A total of 271 patients diagnosed with pancreatic cancer were enrolled in this study.Germline variants of 21 tumor susceptibility genes were detected by next-generation sequencing,and the relationship between germline variants and clinical factors such as age of onset,family history and personal history was analyzed.Results The rate of germline P/LP variants was 6.3%in unselected pancreatic cancer patients,but was high as 17.1%in genetic high-risk group patients(those with a family or personal history of cancer,or early-onset).Genes with higher frequency of germline variants in pancreatic cancer patients were PALB2,BRCA2,and ATM.Conclusion The rate of germline variants in overall pancreatic cancer patients is not high,but it increases significantly in genetic high-risk group,proving the importance of clinical factors in the screening of hereditary pancreatic cancer.

As a potential vectored vaccine,Newcastle disease virus(NDV)has been subject to various studies for vaccine development,while relatively little research has outlined the immunomodulatory effect of the virus in antigen presentation.To elucidate the key inhibitory factor in regulating the interaction of infected dendritic cells(DCs)and T cells,DCs were pretreated with the NDV vaccine strain LaSota as an inhibitor and stimulated with lipopolysaccharide(LPS)for further detection by enzyme-linked immunosorbent assay(ELISA),flow cytometry,immunoblotting,and quantitative real-time polymerase chain reaction(qRT-PCR).The results revealed that NDV infection resulted in the inhibition of interleukin(IL)-12p40 in DCs through a p38 mitogen-activated protein kinase(MAPK)-dependent manner,thus inhibiting the synthesis of IL-12p70,leading to the reduction in T cell proliferation and the secretion of interferon-γ(IFN-γ),tumor necrosis factor-α(TNF-α),and IL-6 induced by DCs.Consequently,downregulated cytokines accelerated the infection and viral transmission from DCs to T cells.Furthermore,several other strains of NDV also exhibited inhibitory activity.The current study reveals that NDV can modulate the intensity of the innate?adaptive immune cell crosstalk critically toward viral invasion improvement,highlighting a novel mechanism of virus-induced immunosuppression and providing new perspectives on the improvement of NDV-vectored vaccine.

Objective:To explore the role of mechanical hemodynamic support (MHS) in mapping and catheter ablation of patients with hemodynamically unstable ventricular tachycardia (VT), report single-center experience in a cohort of consecutive patients receiving VT ablation during MHS therapy, and provide evidence-based medical evidence for clinical practice.Methods:This was a retrospective cohort study. Patients with hemodynamically unstable VT who underwent catheter ablation with MHS at Beijing Anzhen Hospital, Capital Medical University between August 2021 and December 2023 were included. Patients were divided into rescue group and preventive group according to the purpose of treatment. Their demographic data, periprocedural details, and clinical outcomes were collected and analyzed.Results:A total of 15 patients with hemodynamically unstable VT were included (8 patients in the rescue group and 7 patients in the preventive group). The acute procedure was successful in all patients. One patient in the rescue group had surgical left ventricular assist device (LVAD) implantation, remaining 14 patients received extracorporeal membrane oxygenation (ECMO) for circulation support. ECMO decannulation was performed in 12 patients due to clinical and hemodynamic stability, of which 6 patients were decannulation immediately after surgery and the remaining patients were decannulation at 2.0 (2.5) d after surgery. Two patients in the rescue group died during the index admission due to refractory heart failure and cerebral hemorrhage. During a median follow-up of 30 d (1 d to 12 months), one patient with LVAD had one episode of ventricular fibrillation at 6 months after discharge, and no further episodes of ventricular fibrillation and/or VT occurred after treatment with antiarrhythmic drugs. No malignant ventricular arrhythmia occurred in the remaining 12 patients who were followed up.Conclusions:MHS contributes to the successful completion of mapping and catheter ablation in patients with hemodynamically unstable VT, providing desirable hemodynamic status for emergency and elective conditions.

Purpose/Significance Based on the real data of the pediatric prescription circulation platform,a comparative study on us-er characteristics is carried out in order to improve the pediatric prescription circulation service and related platform construction in Chi-na,and to provide references for improving the service capability of the prescription circulation platform.Method/Process Information of children who purchase drugs through the prescription circulation platform of Beijing Children's Hospital from September 10,2019 to July 31,2023 is collected and divided into online drug purchasing group and offline drug purchasing group according to drug access.JMP 17.0(SAS)statistical analysis is used,and Pearson x2 test is used for comparison between groups.Result/Conclusion There are statis-tically significant differences in social demographic characteristics,medical behavior characteristics and single prescription characteristics between the two groups.The pediatric prescription circulation platform has great potential in medical alliance,and online mode is a good application scenario to realize cross-hospital drug circulation.Measures such as building multi-center online drug logistics centers and offline pharmacies according to different user groups can effectively improve the service capability of the platform.

[Objective] To summarize the diagnosis and treatment of Antopol Goldman lesion (AGL) in clinical practice. [Methods] Clinical data and diagnosis and treatment process of one AGL case treated in our hospital were retrospectively analyzed, and relevant literature was reviewed. [Results] The patient presented with painless gross hematuria and right-sided lower back pain.Imaging examination suggested swelling of the right kidney, blood accumulation in the right calyx, renal pelvis and lower ureter, blood clot in the bladder, and multiple small stones in the left kidney.After multidisciplinary consultation, close imaging follow-up, interventional and flexible ureterdscope examination, tumors of hematological diseases, renal hematuria, arteriovenous fistula and collection system were excluded.After conservative treatment, the patient gradually recovered.During the follow-up of 1 year, no hematuria or low back pain recurred. [Conclusion] There is no clear diagnostic standard for AGL.Diagnosis relies on imaging, interventional methods and ureteroscopy.It is necessary to exclude other diseases and adopt conservative treatment.

Objective:To observe the inhibitory effect of dobutamine on proliferation of FLT3-ITD mutated acute myeloid leukemia(AML)cells and explore the feasibility of dobutamine as a monotherapy or in combination with quizartinib for the treatment of this type of AML.Methods:FLT3-ITD mutant cell lines MOLM13 and MV4-11 were cultured in vitro and divided into control group,dobutamine treatment group,quizartinib treatment group,and dobutamine combined with quizartinib treatment group.Cell viability,ROS levels,and apoptosis rate were detected by CCK-8,Flow cytometry,respectively,as well as the expression of YAP1 protein by Western blot.Results:Both dobutamine and quizartinib inhibited the proliferation of FLT3-ITD mutant AML cell lines.Compared with the control group,the dobutamine group exhibited a significant increase in ROS levels(P＜0.01),an increase in apoptosis rates(P＜0.05),and a decrease in YAP1 protein expression(P＜0.05).Compared with the dobutamine group,the combination of quizartinib and dobutamine significantly reduced cell viability(P＜0.05),increased ROS levels(P＜0.01),and decreased YAP1 expression(P＜0.05).Conclusion:Dobutamine as a monotherapy can inhibit the proliferation of FLT3-ITD mutated AML cells,inducing apoptosis.Additionally,the combination of quizartinib enhances the targeted inhibitory effect on FLT3-ITD mutated AML.The mechanism may involve the inhibition of YAP1 protein expression in AML cells of this type,leading to an increase in ROS levels and exerting its anti-tumor effects.

Aim To explore the molecular mechanism of luteolin against acute lung injury by network phar-macology and molecular docking technology,and to conduct experimental verification.Methods The re-lated targets of luteolin were predicted by PubChem and Swiss Target Prediction databases.Acute lung in-jury-related targets were collected through the Gene-Cards database.Venny 2.1 was used to draw the Venn diagram,and the common targets of drug and disease were obtained.The protein interaction network(PPI)was established by String online platform,and the core targets were screened by Cytoscape 3.8.2 software.The functional enrichment analysis of Gene Ontology(GO)and pathway enrichment analysis of Kyoto Ency-clopedia of Gene and Genome(KEGG)were per-formed on the common targets using the DAVID data-base,and the results were visualized.Finally,molecu-lar docking was performed by Auto Dock software,and the molecular results were visualized by Pymol.The mouse acute lung injury model was constructed.HE staining was used to detect histopathology,and Western blot was used to detect lung tissue related proteins.Results After screening,85 common targets were ob-tained.Among them,the core targets were AKT1,EG-FR,SRC,MMP9,ESR1,PTGS2,etc.GO enrichment analysis obtained 265 biological processes,including signal transduction,protein phosphorylation,and nega-tive regulation of apoptosis.There were 48 cells,main-ly including plasma membrane,cell solute,cytoplasm,etc.There are 107 molecular functions,mainly inclu-ding ATP binding,protein serine/threonine/tyrosine ki-nase activity,protein kinase activity and so on.A total of 92 signaling pathway were obtained by KEGG path-way enrichment analysis,which mainly acted on PI3 K-AKT signaling pathway,ErbB signaling pathway,VEGF signaling pathway,etc.Molecular docking results showed that luteolin had good docking activity with core targets AKT1,EGFR,SRC,MMP9,ESR1,PTGS2,MMP2,GSK3 B,KDR and PARP1.The binding ener-gy of ERS1,GSK3B and MMP2 was lower than-5.0 kal·mol-1,and the affinity with luteolin was stronger.The pathological results of lung tissue showed that lute-olin could inhibit inflammatory infiltration and had a strong anti-inflammatory effect in LPS-induced acute lung injury model in mice.Western blot experiments showed that luteolin might alleviate the inflammatory response by inhibiting the phosphorylation of AKT.Conclusions Luteolin can play an anti-acute lung in-jury role through multi-target and multi-channel mecha-nisms,which may be closely related to the inhibition of AKT phosphorylation.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.