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.

BACKGROUND: Neoadjuvant chemoradiotherapy followed by radical surgery has been a common practice for patients with locally advanced rectal cancer, but the response rate varies among patients. This study aimed to develop a ResNet-Vision Transformer based magnetic resonance imaging (MRI)-endoscopy fusion model to precisely predict treatment response and provide personalized treatment. METHODS: In this multicenter study, 366 eligible patients who had undergone neoadjuvant chemoradiotherapy followed by radical surgery at eight Chinese tertiary hospitals between January 2017 and June 2024 were recruited, with 2928 pretreatment colonic endoscopic images and 366 pelvic MRI images. An MRI-endoscopy fusion model was constructed based on the ResNet backbone and Transformer network using pretreatment MRI and endoscopic images. Treatment response was defined as good response or non-good response based on the tumor regression grade. The Delong test and the Hanley-McNeil test were utilized to compare prediction performance among different models and different subgroups, respectively. The predictive performance of the MRI-endoscopy fusion model was comprehensively validated in the test sets and was further compared to that of the single-modal MRI model and single-modal endoscopy model. RESULTS: The MRI-endoscopy fusion model demonstrated favorable prediction performance. In the internal validation set, the area under the curve (AUC) and accuracy were 0.852 (95% confidence interval [CI]: 0.744-0.940) and 0.737 (95% CI: 0.712-0.844), respectively. Moreover, the AUC and accuracy reached 0.769 (95% CI: 0.678-0.861) and 0.729 (95% CI: 0.628-0.821), respectively, in the external test set. In addition, the MRI-endoscopy fusion model outperformed the single-modal MRI model (AUC: 0.692 [95% CI: 0.609-0.783], accuracy: 0.659 [95% CI: 0.565-0.775]) and the single-modal endoscopy model (AUC: 0.720 [95% CI: 0.617-0.823], accuracy: 0.713 [95% CI: 0.612-0.809]) in the external test set. CONCLUSION The MRI-endoscopy fusion model based on ResNet-Vision Transformer achieved favorable performance in predicting treatment response to neoadjuvant chemoradiotherapy and holds tremendous potential for enabling personalized treatment regimens for locally advanced rectal cancer patients.
Humans ; Rectal Neoplasms/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Male ; Female ; Middle Aged ; Neoadjuvant Therapy/methods* ; Aged ; Adult ; Chemoradiotherapy/methods* ; Endoscopy/methods* ; Treatment Outcome

This study explores the role and underlying molecular mechanisms of fucoidan sulfate(FPS) in regulating heme oxygenase-1(Hmox1)-mediated ferroptosis to ameliorate myocardial injury in diabetic cardiomyopathy(DCM) through in vivo and in vitro experiments and network pharmacology analysis. In vivo, a DCM rat model was established using a combination of "high-fat diet feeding + two low-dose streptozotocin(STZ) intraperitoneal injections". The rats were randomly divided into four groups: normal, model, FPS, and dapagliflozin(Dapa) groups. In vitro, a cellular model was created by inducing rat cardiomyocytes(H9c2 cells) with high glucose(HG), using zinc protoporphyrin(ZnPP), an Hmox1 inhibitor, as the positive control. An automatic biochemical analyzer was used to measure blood glucose(BG), serum aspartate aminotransferase(AST), serum lactate dehydrogenase(LDH), and serum creatine kinase-MB(CK-MB) levels. Echocardiography was used to assess rat cardiac function, including ejection fraction(EF) and fractional shortening(FS). Pathological staining was performed to observe myocardial morphology and fibrotic characteristics. DCFH-DA fluorescence probe was used to detect reactive oxygen species(ROS) levels in myocardial tissue. Specific assay kits were used to measure serum brain natriuretic peptide(BNP), myocardial Fe~(2+), and malondialdehyde(MDA) levels. Western blot(WB) was used to detect the expression levels of myosin heavy chain 7B(MYH7B), natriuretic peptide A(NPPA), collagens type Ⅰ(Col-Ⅰ), α-smooth muscle actin(α-SMA), ferritin heavy chain 1(FTH1), solute carrier family 7 member 11(SLC7A11), glutathione peroxidase 4(GPX4), 4-hydroxy-2-nonenal(4-HNE), and Hmox1. Immunohistochemistry(IHC) was used to examine Hmox1 protein expression patterns. FerroOrange and Highly Sensitive DCFH-DA fluorescence probes were used to detect intracellular Fe~(2+) and ROS levels. Transmission electron microscopy was used to observe changes in mitochondrial morphology. In network pharmacology, FPS targets were identified through the PubChem database and PharmMapper platform. DCM-related targets were integrated from OMIM, GeneCards, and DisGeNET databases, while ferroptosis-related targets were obtained from the FerrDb database. A protein-protein interaction(PPI) network was constructed for the intersection of these targets using STRING 11.0, and core targets were screened with Cytoscape 3.9.0. Molecular docking analysis was conducted using AutoDock and PyMOL 2.5. In vivo results showed that FPS significantly reduced AST, LDH, CK-MB, and BNP levels in DCM model rats, improved cardiac function, decreased the expression of myocardial injury proteins(MYH7B, NPPA, Col-Ⅰ, and α-SMA), alleviated myocardial hypertrophy and fibrosis, and reduced Fe~(2+), ROS, and MDA levels in myocardial tissue. Furthermore, FPS regulated the expression of ferroptosis-related markers(Hmox1, FTH1, SLC7A11, GPX4, and 4-HNE) to varying degrees. Network pharmacology results revealed 313 potential targets for FPS, 1 125 targets for DCM, and 14 common targets among FPS, DCM, and FerrDb. Hmox1 was identified as a key target, with FPS showing high docking activity with Hmox1. In vitro results demonstrated that FPS restored the expression levels of ferroptosis-related proteins, reduced intracellular Fe~(2+) and ROS levels, and alleviated mitochondrial structural damage in cardiomyocytes. In conclusion, FPS improves myocardial injury in DCM, with its underlying mechanism potentially involving the regulation of Hmox1 to inhibit ferroptosis. This study provides pharmacological evidence supporting the therapeutic potential of FPS for DCM-induced myocardial injury.
Animals ; Ferroptosis/drug effects* ; Rats ; Diabetic Cardiomyopathies/physiopathology* ; Male ; Rats, Sprague-Dawley ; Polysaccharides/pharmacology* ; Heme Oxygenase-1/genetics* ; Myocytes, Cardiac/metabolism* ; Myocardium/pathology* ; Humans ; Cell Line ; Heme Oxygenase (Decyclizing)

OBJECTIVE: To investigate the effectiveness of Xuanshen Yishen Decoction (XYD) in the treatment of hypertension. METHODS: Hospital electronic medical records from 2019-2023 were utilized to emulate a randomized pragmatic clinical trial. Hypertensive participants were eligible if they were aged ⩾40 years with baseline systolic blood pressure (BP) ⩾140 mm Hg. Patients treated with XYD plus antihypertensive regimen were assigned to the treatment group, whereas those who followed only antihypertensive regimen were assigned to the control group. The primary outcome assessed was the attainment rate of intensive BP control at discharge, with the secondary outcome focusing on the 6-month all-cause readmission rate. RESULTS: The study included 3,302 patients, comprising 2,943 individuals in the control group and 359 in the treatment group. Compared with the control group, a higher proportion in the treatment group achieved the target BP for intensive BP control [8.09% vs. 17.5%; odds ratio (OR)=2.29, 95% confidence interval (CI)=1.68 to 3.13; P<0.001], particularly in individuals with high homocysteine levels (OR=3.13; 95% CI=1.72 to 5.71; P<0.001; P for interaction=0.041). Furthermore, the 6-month all-cause readmission rate in the treatment group was lower than in the control group (hazard ratio=0.58; 95% CI=0.36 to 0.91; P=0.019), and the robustness of the results was confirmed by sensitivity analyse. CONCLUSIONS XYD could be a complementary therapy for intensive BP control. Our study offers real-world evidence and guides the choice of complementary and alternative therapies. (Registration No. ChiCTR2400086589).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Antihypertensive Agents/pharmacology* ; Blood Pressure/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Hypertension/physiopathology* ; Patient Readmission ; Treatment Outcome

Homo- or heterodimeric compounds that affect dimeric protein function through interaction between monomeric moieties and protein subunits can serve as valuable sources of potent and selective drug candidates. Here, we screened an in-house dimeric natural product collection, and panepocyclinol A (PecA) emerged as a selective and potent STAT3 inhibitor with profound anti-tumor efficacy. Through cross-linking C712/C718 residues in separate STAT3 monomers with two distinct Michael receptors, PecA inhibits STAT3 DNA binding affinity and transcription activity. Molecular dynamics simulation reveals the key conformation changes of STAT3 dimers upon the di-covalent binding with PecA that abolishes its DNA interactions. Furthermore, PecA exhibits high efficacy against anaplastic large T cell lymphoma in vitro and in vivo, especially those with constitutively activated STAT3 or STAT3^Y640F. In summary, our study describes a distinct and effective di-covalent modification for the dimeric compound PecA to disrupt STAT3 function.

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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 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 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.