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.

Aim To investigate the protective effect of berberine(BBR)on mice with unilateral ureteral obstr-uction(UUO)and explore its mechanism.Methods C57BL/6 mice were randomly divided into the sham group,UUO group,and BBR treatment groups(50,100 and 200 mg·kg-1),with eight mice in each group.Except the sham group,the other groups were subjected to left ureteral ligation to establish the UUO model.Af-ter modeling,the mice in the sham and UUO groups were fed normal saline,and the mice in the BBR treat-ment groups were fed(50,100,200)mg·kg-1 BBR by gavage for 14 days,respectively.Biochemical analy-zer was employed to detect the levels of serum creati-nine(Scr)and blood urea nitrogen(BUN).HE,Mas-son,TUNEL and immunohistochemical staining were used to observe the pathological changes of renal tis-sue.ELISA was employed to detect the expression of pro-inflammatory cytokines in renal tissue homogenate.Western blot was used to detect the protein levels of NF-κB p65,TGF-β1 and CTGF in mouse kidney.Re-sults Compared with the UUO group,the levels of Scr and BUN in the BBR group were significantly reduced.Renal injury and interstitial fibrosis were alleviated.The expression of pro-inflammatory cytokines decreased in kidney.The expression of NF-κB p65,TGF-β1 and CTGF decreased.All results showed some degree of dose dependence.Conclusion Berberine has a sig-nificant protective effect on unilateral ureteral obstruc-tion mice,and the mechanism may be that BBR has the potential to inhibit NF-κB p65/TGF-β1/CTGF signa-ling pathway,thus reducing renal inflammation and fi-brosis.

Objective:To describe the current situation of mental health service utilization of community pa-tients with five mental disorders in Inner Mongolia Autonomous Region and provide reference for health education and formulating relevant policies.Methods:The multistage stratified sampling method with unequal probability was used to select a total of 12 315 community residents aged 18 and over in Inner Mongolia Autonomous Region.Using Composite International Diagnostic Interview,mood disorders,anxiety disorders,substance use disorders,intermit-tent explosive disorders,and eating disorders,and health service utilization were investigated.Descriptive statistics was completed by single factor analysis method.Results:The lifetime rates of consultation and treatment of any mental disorder were 18.7％and 10.2％,respectively.The highest proportion of patients received treatment by non-medical professionals was 31.4％,followed by psychiatrists in psychiatric hospital or psychologists in general hospitals.Among the patients,1.1％of them received medication,and 2.5％received psychotherapy.Conclusion:The utilization rate of mental health services in community patients with five mental disorders is relatively low.It is necessary to conduct health education for medical help seeking properly.

Objective:To investigate the correlation between triglyceride glucose index (TyG) and cerebral hemodynamic score values (CVHI) in population receiving physical examination.Methods:In this cross-sectional study, 12 785 people who had medical checkups and received physical examination at the Health Management Center of the First Affiliated Hospital of Xinjiang Medical University from June 2020 to May 2021 and met the criteria for natriuresis were selected as the study subjects. The general information, physical examination results and biochemical indexes were collected in these people. Using the visualization score box, the study subjects were divided into 4 groups according to TyG<8.379, 8.379-8.785, 8.785-9.236, and≥9.236: Q1 group (3 196 cases), Q2 group (3 196 cases), Q3 group (3 197 cases), and Q4 group (3 196 cases). The differences of the indices among the four groups were compared. The logistic regression analysis and Spearman rank correlation analysis were used to assess the correlation between TyG and CVHI in the population undergoing health checkups.Results:CVHI decreased gradually with the increase of TyG, and the abnormal rate of CVHI increased gradually with the increase of TyG ( H=451.007, χ2=188.571) (both P<0.001). The detection rates of individuals at high risk of CVHI in the Q1, Q2, Q3, and Q4 groups was 15.2%, 22.3%, 27.2%, and 35.3%, respectively. When TyG≥9.236, CVHI decreased in the population receiving physical examination ( OR=1.282, 95% CI: 1.028-1.598), and CVHI was negatively correlated with TyG ( rs=-0.200) (both P<0.05). Conclusion:There is a negative correlation between TyG and CVHI in the population receiving physical examination, and when TyG≥9.236, it suggests that cerebral hemodynamics may be abnormal, which warrants attention.

Objective:To investigate the value of left ventricular systolic synchrony assessed by gated myocardial perfusion imaging(GMPI)in predicting major adverse cardiovascular events(MACE)in elderly patients with coronary heart disease(CHD).Methods:In this retrospective study, clinical data from elderly patients who had completed a two-day assessment of resting-loading GMPI between September 2012 and February 2014 in Beijing Hospital were collected, including the summed stress score(SSS)for total ischemic burden, measured by GMPI, left ventricular ejection fraction(LVEF), peak filling rate(PFR), phase band width(PBW), phase standard deviation(PSD)and phase entropy(PE).Follow-up of MACE was conducted.Independent risk factors for MACE were analyzed using a multifactorial Cox proportional hazards regression model, and the cumulative MACE incidence was analyzed using the Kaplan-Meier survival curve.Results:A total of 427 subjects were enrolled, including 200(46.8%)men, with a mean age of 74.1±6.5(60-92)years and 323(75.6%)aged ≥ 70 years.The median follow-up time was 54.7 months.At the end of follow-up, MACE occurred in 47 patients(11.0%).Compared with the group without MACE, the incidences of hypertension, hyperlipidemia, and hyperuricemia were significantly higher( χ2=5.20, 5.62, 3.86, all P<0.05), LVEF and PFR were significantly lower( t=-5.51, -5.23, both P<0.001), and SSS, PSD, PBW, and PE were significantly higher( Z=4.78, t=5.14, 5.78, 5.62, all P<0.001)in the MACE group.The results of Cox proportional hazards regression model analysis suggested that age ≥ 70(hazard ratio: 2.57, 95% CI: 1.08-6.13), abnormal perfusion(hazard ratio: 2.60, 95% CI: 1.31-5.15), increased PSD(hazard ratio: 3.72, 95% CI: 1.72-8.05)and increased PE(hazard ratio: 4.09, 95% CI: 1.94-8.63)were independent risk factors for the occurrence of MACE(all P<0.05).Further analysis on 323 patients ≥ 70 years indicated that abnormal perfusion(hazard ratio: 2.96, 95% CI: 1.40-6.26), increased PSD(hazard ratio: 3.51, 95% CI: 1.56-7.89), and increased PE(hazard ratio: 4.49, 95% CI: 2.08-9.71)were independent risk factors for MACE( P<0.05 for all). Conclusions:Parameters of GMPI systolic synchrony analysis can very well identify the population at high risk of MACE in elderly patients with CHD.

AIM To establish a UPLC method for the simultaneous content determination of chlorogenic acid,protocatechuic acid,protocatechualdehyde,cryptochlorogenic acid,syringic acid,1,3-dicaffeoylquinic acid,cynaroside,isochlorogenic acid B,neochlorogenic acid,isochlorogenic acid A,hesperidin,caffeic acid,isochlorogenic acid C and rosmarinic acid in Waigan Fengsha Granules.METHODS The analysis was performed on a 30℃ thermostatic Waters ACQUITY UPLC.HSS C18 column(2.1 mm×100 mm,1.8 μm),with the mobile phase comprising of acetonitrile-0.2%phosphoric acid flowing at 0.2 mL/min in a gradient elution manner,and the detection wavelengths were set at 275,327 nm.Subsequently,chemometric analysis was performed.RESULTS Fourteen constituents showed good linear relationships within their own ranges(r≥0.999 6),whose average recoveries were 95.68%-104.8%with the RSDs of 0.7%-3.0%.Seven batches of samples were clustered into two types,three principal components demonstrated the acumulative contribution rate of 93.031%.CONCLUSION This accurate and reliable method can be used for the quality control of Waigan Fengsha Granules.

Objective:To investigate the efficacy and prognosis of CLAG±DAC (Clofarabine, Cytarabine, G-CSF±Decitabine) chemotherapy in patients with relapsed/refractory acute myeloid leukemia (R/R AML) .Methods:Continuous cases of R/R AML treated with the CLAG+DAC protocol or CLAG alone at the First Affiliated Hospital of Soochow University from January 2017 to December 2021 were retrospectively analyzed. The baseline characteristics, individual treatment regimen, treatment effect, disease progression, and survival status of patients were recorded. The factors influencing the efficacy of the CLAG±DAC chemotherapy regimens were analyzed, and the overall survival (OS) time after reinduction was calculated using the Kaplan-Meier method.Results:This study included a total of 53 patients, with 33 male patients and an average age of 40.6 years. Thirty-three patients achieved complete remission (CR+CRi) of the disease after the CLAG±DAC chemotherapy regimen and six patients achieved partial remission (PR), while 14 did not. Thirty-two patients eventually underwent hematopoietic stem cell transplantation, and the median OS of the patients was 55.9 months until follow-up. Patients with disease remission after the application of the CLAG±DAC chemotherapy had a significantly longer survival time than those without remission ( P<0.001). The results of the multifactorial analysis have revealed that combined DAC ( OR=4.60, 95% CI 1.14-23.5, P=0.04) and DNMT3A mutation ( OR=0.14, 95% CI 0.01-0.89, P=0.05) were the factors influencing the efficacy of the CLAG±DAC chemotherapy regimen. The remission rate was relatively higher in patients with R/R AML combined with FLT3-ITD mutation by applying the DAC+CLAG regimen ( OR=10.84, 95% CI 1.48-288.50, P=0.04) . Conclusion:The CLAG±DAC regimen is considered effective in patients with R/R AML, whereas decitabine combined with the CLAG regimen is more suitable for patients with R/R AML combined with FLT3-ITD mutation.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

Objective To study the composition,abundance,and functional profiles of the intestinal microbiota in infants and young children with Kawasaki disease(KD)during the acute phase,and to explore the potential role of intestinal microbiota in the pathogenesis of KD.Methods Six children aged 0-3 years with acute KD admitted to the Department of Cardiology,Children's Hospital Affiliated to Capital Institute of Pediatrics from July to October 2021 were prospectively included as the KD group.Six age-and sex-matched healthy children who underwent physical examinations at the hospital during the same period were selected as the healthy control group.Metagenomics sequencing was used to detect and compare the differences in the microflora structure and functional profiles of fecal samples between the two groups.Results There were significant differences in the structural composition and diversity of intestinal microbiota between the two groups(P<0.05).Compared with the healthy control group,the abundance of Listeria_monocytogenes(family Listeriaceae and genus Listeria),Bifidobacterium_rousetti,Enterococcus_avium,and Enterococcus_hirae was significantly higher in the intestinal microbiota in the KD group(|LDA|>2.0,P<0.05).The steroid degradation and apoptosis pathways were significantly upregulated in the KD group compared with the healthy control group,while the Bacterial_secretion_system,Sulfur_metabolism,Butanoate_metabolism,Benzoate_degradation,β-alanine metabolism,and α-linolenic acid pathways were significantly downregulated(|LDA|>2,P<0.05).Conclusions There are significant differences in the structure and diversity of intestinal microbiota between children aged 0-3 years with acute KD and healthy children,suggesting that disturbances in intestinal microbiota occur during the acute phase of KD.In particular,Listeria_monocytogenes,Enterococcus_avium,and Enterococcus_hirae may be involved in the pathogenesis of KD through steroid degradation and apoptosis pathways.

Objective To evaluate healthcare-associated infection(HAI)status and influencing factors in coronary heart disease(CHD)patients after percutaneous coronary intervention(PCI)treatment,and construct a risk predic-tion model.Methods CHD patients who underwent PCI in a hospital from May 2019 to October 2023 were retro-spectively selected as the research subjects.Infection status of the CHD patients was analyzed.Patients were ran-domly divided into a modeling set and a testing set in a 7:3 ratio.Univariate and multivariate logistic regression ana-lyses were performed to analyze the data in the modeling set and determine the influencing factors for HAI in pa-tients.R software was used to construct and validate a nomogram model.Results A total of 858 CHD patients were included in the analysis,601 in the modeling set and 257 in the testing set.In the modeling set,41 cases were in the infected group and 560 cases in the non-infected group.The incidence of HAI in CHD patients after PCI treat-ment was 6.88％(59/858).Infection site were mainly upper respiratory tract and urinary tract.A total of 74 pathogens were isolated,including Gram-positive bacteria,Gram-negative bacteria,and fungi being 39,31,and 4 strains,respectively.Multivariate analysis showed that old age,combined diabetes,high grade of New York Heart Association(NYHA)classification,and invasive procedures were all risk factors for HAI in CHD patients after PCI treatment(all P＜0.05),while high mini-nutritional assessment short-form(MNA-SF)score was a protective fac-tor(P＜0.05).The area under the receiver operating characteristic(ROC)curve(AUC)of the nomogram predic-tion model constructed based on the above five indicators was 0.894(95％CI:0.815-0.931),with a sensitivity of 89.0％and a specificity of 82.5％.The testing set data validation showed an AUC value of 0.879(95％CI:0.801-0.923),with a sensitivity of 87.5％and a specificity of 81.3％,which were comparable to the modeling set and presented the stability of the model.The H-L goodness of fit test showed no statistical significance(P＞0.05),in-dicating that the model didn't exhibit overfitting.Calibration curve analysis showed that the model had good consis-tency.Decision curve analysis confirmed that the model had practical value in clinical practice.Conclusion The no-mogram model has a good predictive ability for HAI in CHD patients after PCI treatment,and can provide a simple and effective evaluation tool for medical staff to identify HAI high-risk individuals.