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.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Objective To study the effect of drinking carbohydrate drinks before cesarean section on mothers and neonates,and to explore the application value of drinking carbohydrate drinks before cesarean section.Methods The clinical data of 206 singleton women who underwent selective cesarean section in Obstetrics and Gynecology Hospital,Fudan University from Jun 2020 to Jun 2021 were retrospectively studied.Patients were divided into enhanced recovery after delivery(ERAD)group and control group according to whether drinking carbohydrate drinks before cesarean section.A retrospective cohort study was conducted to analyze the effect of preoperative carb drinks on preoperative fluid supplementation,postoperative rehabilitation and neonatal prognosis.Results Among patients who fasted for less than 12 hours,the ERAD group had a lower fluid supplementation rate and a smaller average fluid supplementation volume compared to the control group(P＜0.05).The ERAD group had a lower rate of prokinetic agent using after surgery(P＜0.05).Among women without a history of abdominal surgery,the ERAD group had less blood loss 24 hours after surgery(P＜0.05).There were no significant differences in postoperative fever rate,incidence of nausea and vomiting,time of first flatus,neonatal apgar score,exit observation room neonatal blood,and neonatal neonatal intensive care unit(NICU)admission rate between the two groups.Among newborns with high-risk factors for hypoglycemia,the ERAD group had lower enter observation room neonatal blood compared to the control group,and a higher incidence of hypoglycemia(P＜0.05).Conclusion Oral intake of carbohydrate drinks before cesarean section may be beneficial in reducing fluid supplementation before elective cesarean section,promoting postoperative gastrointestinal function recovery,and reducing postoperative bleeding.However,it may be related to the occurrence of neonatal hypoglycemia.

Objective To explore the alterations in gray matter volume(GMV)in adolescents with bipolar disorder(BD).Methods 36 BD patients(BD group)and 37 healthy controls(HC group)who underwent magnetic resonance imaging(MRI)for artificial visual inspection in Affiliated Hangzhou First People's Hospital,School of Medicine,Westlake University from September 2019 to December 2021 were selected.Structural MRI data were processed by using FreeSurferv6.0.0,and statistical analysis were conducted by using SPSS 26.0 and R language software.Receiver operating characteristic(ROC)curve were employed to assess the diagnostic efficacy of various brain regions.Results Compared to HC group,patients in BD group exhibited significant reductions in GMV in the right superior frontal gyrus,right nucleus accumbens,left insula,right lateral orbitofrontal cortex,and right medial orbitofrontal cortex(P＜0.05).ROC curve analysis indicated that area under the curve(AUC)for the right superior frontal gyrus and right nucleus accumbens were 0.739 and 0.712 respectively,while the combined AUC for multiple brain regions was 0.820.Conclusion Adolescents with BD show significant reductions in GMV in specific brain regions,provide reference for the early identification and pathological mechanism research of BD.

OBJECTIVE To systematically evaluate the efficacy and safety of transcatheter arterial chemoembolization （TACE） combined with anti-angiogenic drugs for the treatment of unresectable primary liver cancer （PLC）. METHODS Retrieved from Chinese and English databases such as CNKI， the Cochrane Library， Google， and Baidu Academic， randomized controlled trial （RCT） about TACE combined with anti-angiogenic drugs for the treatment of unresectable PLC were collected from the inception to May 27， 2024. After screening the literature， extracting data， and evaluating the quality of the literature， network meta-analysis was performed using R 4.2.2 and Stata 17.0. RESULTS A total of 44 RCT were included， involving 5 607 patients and 8 interventions. The network meta-analysis results showed that for prolonging median overall survival （mOS） and median progression- free survival （mPFS）， TACE+apatinib had the best efficacy， with TACE+apatinib and TACE+sorafenib ranking as the top two. For improving objective response rate （ORR） and disease control rate （DCR）， TACE+donafenib had the best efficacy， with TACE+ donafenib and TACE+ lenvatinib ranking as the top two. In terms of safety， TACE+donafenib was the best， with TACE+donafenib and TACE+apatinib ranking as the top two. CONCLUSIONS TACE+apatinib and TACE+donafenib have good efficacy for patients with unresectable PLC， and TACE+donafenib has the best safety profile.

Objective To investigate the distribution of traditional Chinese medicine(TCM)syndromes in patients with type 2 diabetic retinopathy(T2DR)and to explore the correlation of TCM syndromes with serum inflammatory factors and adiponectin(APN)levels,so as to provide evidence for TCM syndrome differentiation of T2DR.Methods A cross-sectional case-control study was conducted in 42 patients(involving 84 eyes)diagnosed as T2DR in the Department of Ophthalmology,Ganzhou People's Hospital from September 2022 to March 2023.The correlation between fundus fluorescein angiography(FFA)staging and TCM syndrome differentiation in patients with T2DR was explored.The relationship between TCM syndrome types and serum levels of inflammatory factors and APN,as well as the differences in serum inflammatory factors and APN levels of the patients with various FFA stages were analyzed.The correlation between each variable and TCM syndrome types in patients with T2DR was investigated.Results(1)Among the 42 patients with T2DR,27 cases were male and 15 cases were female,and their age averaged(54.0±12.0)years old.Among them,14 cases(33.3％)were differentiated as liver-kidney deficiency with malnutrition of eye collateral syndrome,15 cases(35.7％)were differentiated as yin-essence deficiency with internal dry-heat syndrome,9 cases(21.4％)were differentiated as qi-yin deficiency with collateral stasis and obstruction syndrome,4 cases(9.5％)were differentiated as yin-yang deficiency with blood stasis and phlegm coagulation syndrome,and none case(0.0％)was differentiated as spleen dysfunction and water-damp obstruction syndrome.(2)FFA staging showed that FFA staging ≥ 4[i.e.,having proliferative diabetic retinopathy(PDR)]was found in 78.6％(11/14)of the patients with liver-kidney deficiency with malnutrition of eye collaterals syndrome,73.3％(11/15)of the patients with yin-essence deficiency with internal dry-heat syndrome,100％(9/9)of the patients with qi-yin deficiency with collateral stasis and obstruction syndrome,and 100％(4/4)of the patients with yin-yang deficiency with blood stasis and phlegm coagulation syndrome.But the intergroup comparison showed no significant differences among various syndrome types(P=0.272).(3)Among the 42 patients with T2DR,35 patients(83.3％)had higher level of tumor necrosis factor-α(TNF-α),28 patients(68.3％)had higher level of C-reactive protein(CRP)and 38 patients(90.5％)had higher level of glycosylated hemoglobin(HbA1c)than the normal.However,there was no significant difference in the levels of serum inflammatory factors of TNF-α,CRP,interleukin-6(IL-6)and vascular endothelial growth factor(VEGF),APN and HbA1c among the patients with different FFA stages(P＞0.05),neither did the difference in serum APN,TNF-α,CRP,IL-6 and VEGF levels among the patients with different TCM syndrome types(P＞0.05).(4)The correlation analysis showed that the patients with yin-yang deficiency with blood stasis and phlegm coagulation syndrome had a shorter course of eye diseases than the patients with liver-kidney deficiency with malnutrition of eye collaterals syndrome(r=-0.467,P=0.051),had higher CRP level than the patients with yin-essence deficiency with internal dry-heat syndrome(r=0.592,P=0.010),and had higher CRP level(r=0.668,P=0.013)and a longer course of diabetes(r=0.629,P=0.021)than the patients with qi-yin deficiency with collateral stasis and obstruction syndrome.Conclusion Increased serum TNF-α and CRP expressions are presented in the patients with T2DR.Liver-kidney deficiency with malnutrition of eye collaterals syndrome and yin-essence deficiency with internal dry-heat syndrome are the common syndromes in T2DR.Yin-yang deficiency with blood stasis and phlegm coagulation syndrome is closely correlated with CRP level,and the patients with yin-yang deficiency with blood stasis and phlegm coagulation syndrome have a longer course of diabetes.

Objective To investigate the effect of MALAT1 expressions on cell proliferation and apoptosis in astrocytes by regulating mitogen-activated protein kinase(MAPK)/extracellular signal-regulated kinase(ERK1,2)pathway.Methods The MALAT1 gene was knocked down and over-expressed in C8-D1A cells by lentiviral and plasmid vectors,respectively.The expressions of MALAT1,cell proliferation-related markers(Ki67,MCM2,PCNA)and apoptosis-related proteins(Caspase-3,Bax,Bcl-2)were detected by quantitative real-time polymerase chain reaction(qPCR).CCK-8 assay and flow cytometry were used for cell proliferation and apoptosis in C8-D1A cells.Immunofluorescence was adopted to detect the protein expressions of Caspase-3 and Ki67.Western blotting was used to detect the protein expressions of Caspase-3,Bax,Bcl-2,ERK1/2,p-ERK1/2,p38MAPK and p-p38MAPK.Results Compared with the control group,over-expressed MALAT1 inhibited cell proliferation and induced cell apoptosis in C8-D1A cells while the knockdown of MALAT1 significantly enhanced cell proliferation and anti-apoptotic ability in C8-D1A cells.The proportion of C8-D1A cells in G0/G1-phase and G2/M-phase was higher than in the control group as evidenced by flow cytometry,but was lower in S-phase.Meanwhile,data showed that Caspase-3 was increased while p-ERK1/2 was decreased in terms of protein levels.The mRNA expressions of Ki67 and PCNA were decreased.After knockdown of MALAT1,the proportion of C8-D1A cells in S-phase was higher,but was lower in G2/M-phase.The protein expressions of Caspase-3 and Bax decreased while those of p-ERK1/2 and p-p38MAPK increased.The mRNA expressions of Ki67,MCM2 and PCNA were increased.The differences were all statistically significant(P＜0.05).Conclusion MALAT1 promotes astrocyte apoptosis and inhibits proliferation by regulating the MAPK/ERK1,2 signaling pathway.

Hip fracture in the elderly is characterized by high incidence, high disability rate, and high mortality and has been recognized as a public health issue threatening their health. Surgery is the preferred choice for the treatment of elderly patients with hip fracture. However, lower extremity deep venous thrombosis (DVT) has an extremely high incidence rate during the perioperative period, and may significantly increase the risk of patients′ death once it progresses to pulmonary embolism. In response to this issue, the clinical guidelines and expert consensuses all emphasize active application of comprehensive preventive measures, including basic prevention, physical prevention, and pharmacological prevention. In this prevention system, basic prevention is the basis of physical and pharmacological prevention. However,there is a lack of unified and definite recommendations for basic preventive measures in clinical practice. To this end, the Orthopedic Nursing Professional Committee of the Chinese Nursing Association and Nursing Department of the Orthopedic Branch of the China International Exchange and Promotive Association for Medical and Health Care organized relevant nursing experts to formulate Expert consensus on perioperative basic prevention for lower extremity deep venous thrombosis in elderly patients with hip fracture ( version 2024) . A total of 10 recommendations were proposed, aiming to standardize the basic preventive measures for lower extremity DVT in elderly patients with hip fractures during the perioperative period and promote their subsequent rehabilitation.

Post-endoscopic retrograde cholangiopancreatography pancreatitis(PEP)is one of the most common complications after endoscopic retrograde cholangiopancreatography(ERCP).Numerous PEP prediction models have been established based on different statistical methods at home and abroad.The PEP prediction model,as a tool for evaluating and screening high-risk populations,can provide a basis for medical staff to find high-risk PEP patients early and take effective preventive measures.In recent years,new PEP prediction models have appeared one after another,but there is still a lack of recognized reliable prediction models in clinic.This article reviews the research status of PEP risk prediction models,aim to provide a direction for establishing a more reliable,accurate,and practical PEP risk prediction model in the later period.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.