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 whether alisol A (AA) could improve the blood brain barrier (BBB) mediated cortex cerebral ischemia-repeifusion injury (CIRI) by inhibiting matrix metalloproteinase 9 (MMP-9). Methods The global cerebral ischemia- reperfusion (GCI/R) model in mice was established, and the AA was intragastric injected subsequently for seven days. The modified neurological severity scores (mNSS), open field test and Y-maze test were applied to detect neurological function. Magnetic resonance spectroscopy (MRS) was used to detect relevant neu- rosubstance metabolism in cortex of mice. Transmission electron microscope (TEM) was employed to observe the ultrastructure of BBB in cortex. Western blot and immunohistochemistry were used to detect the MMP-9 level in cortex. The binding possibility of A A and MMP-9 was determined by molecular docking. Results Compared with Sham group, mice in GCI/R group have an increased mNSS score but decreased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01). While mice in GCI/R + AA group have a decreased mNSS score but increased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01) compared with GCI/R group. MRS results found that in cortex of GCI/R group mice, the level of GABA and NAA significantly decreased while the Cho, mI and Tau level increased (P<0.01). Whereas in GCI/R + AA group mice, the GABA and NAA level increased and the Cho, ml and Tau decreased significantly (P<0.01). By TEM we observed that the basilemma of cerebral microvessels collapsed, the lumen narrowed, the endothelial cells were active and plasma membranes ruffled, gaps between cells were enlarged and tight junctions were damaged and the end feet of astrocytes were swollen in GCI/R group mice. While in GCI/R + AA group mice, the lumen was filled, plasma membranes of endothelial cells were smooth, tight junctions were complete and end feet of astrocytes were in normal condition. Western blot and immunohistochemistry both found that the MMP-9 level increased in GCI/R group mice (P < 0.01) and decreased in GCI/R + AA group mice (P < 0.05). Molecular docking proved the binding between aliso A and MMP9 through TYR-50 and ARG-106, and the binding energy was calculated as -6.24 kcal · mol

Five flavonoid glycosides were isolated from the methanol and ethyl acetate fractions of the ethanol extract of Diphylleia sinensi by using various chromatographic methods, including silica gel, MCI gel, Sephadex LH-20, ODS and semi-preparative HPLC. The structures of the isolated compounds were identified as diphyflavonoid A (1), diphyflavonoid B (2), quercetin-3-O-β-D-glucopyranoside (3), kaempferol-3-O-β-D-glucopyranoside (4), kaempferol-3-O-(6″-O-acetyl)-β-D-glucopyranoside (5) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, and MS). Compounds 1 and 2 were two new flavonoid glycosides, and compounds 3 and 5 were isolated from the genus Diphylleia for the first time.

Amantadine(AMD)residue can accumulate in organisms through the food chain and cause serious harm to human body.AMD can specifically bind to AMD specific aptamer and cause its conformation to change from a random single strand to a stem-loop structure.To avoid the influence of excess nucleotides on binding of aptamer to AMD,the truncation of the AMD original aptamer J was optimized by retaining an appropriate stem-loop structure,and a new type of truncation aptamers was developed in this work.By comparing the truncated aptamer with the original aptamer,it was found that the truncated aptamer J-7 had better affinity and specificity with AMD.The detection limit of AMD was 0.11 ng/mL by using J-7 as specific recognition element and molybdenum disulfide nanosheet(MoS2Ns)as signal amplification element.The developed method base on truncated aptamer J-7 was used for detection of AMD in milk,yogurt and SD rat serum samples for the first time with recoveries of 86.6%-108.2%.This study provided a reference for truncating other long sequence aptamers and provided a more sensitive detection method for monitoring AMD residues in food.

Objective To explore the context and hotspot changes of forensic mixed stain research through bibliometric approach.Methods The literature of forensic mixed stain included in the core col-lection of Web of Science database from 2011 to 2022 were collected as the study object,and the an-nual publication number,countrie(region),institution,journal,keywords,etc.were bibliometrically and visually analyzed using the R-based Bibliometrix 1.1.6 package and VOSviewer 1.6.18 software.Re-sults A total of 732 articles on forensic mixed stain were included from 2011 to 2022,with the an-nual number of articles published and the annual citation frequency showing a steady increase year by year.Among the 59 countries(regions)with the most published articles,the United States ranked first with 246 articles,followed by China with 153 articles.The literature came from 104 journals,and the total number of articles published in the top 10 journals was 633.FORENSIC SCI INT GENET ranked first with 307 articles.Visual analysis using VOSviewer software showed that keywords could be divided into four research clusters,namely the genetic marker development group(blue),the mixed stain typing analysis theory group(red),the sequencing analysis group(yellow),and the case sample research group(green).It can be divided into four development stages in terms of different time peri-ods:early development(2011-2013),middle development(2014-2016),rapid development(2017-2020)and latest development(2021-2022).Conclusion The number of publications by domestic and foreign scholars in the study of mixed stain in forensic science is showing a relatively stable trend.Machine learning,next generation sequencing and other research have been the hottest topics that have attracted the most attention in recent years,which is expected to further develop the theory of mixed stain typing and sequencing analysis in forensic mixed stain research.

This article discussed the evolution of the traditional preparation process of Pinelliae Rhizoma Fermentata.The production methods for Pinelliae Rhizoma Fermentata in Song Dynasty include cake-making of Pinelliae Rhizoma together with ginger juice and fermentation after cake-making,and the former method of cake-making was the mainstream.The process technology in Jin and Yuan Dynasties inherited from that in Song Dynasty,and the application of Pinelliae Rhizoma Fermentata had certain limitations.The medical practitioners of Ming Dynasty elucidated the mechanism of processing of Pinelliae Rhizoma Fermentata,and proposed the view of"sliced Pinelliae Rhizoma being potent while fermented Pinelliae Rhizoma being mild".In the Ming Dynasty,LI Shi-Zhen defined the cake-making process and fermentation process for Pinelliae Rhizoma,and HAN Mao's Han Shi Yi Tong(Han's Clear View of Medicine)contained five prescriptions for the processing of Pinelliae Rhizoma Fermentata,which had the epoch-making signficance in the expansion of prescriptions for the processing of Pinelliae Rhizoma Fermentata.In the Qing Dynasty,HAN Fei-Xia's ten methods for making Pinelliae Rhizoma Fermentata were summarized on the basis of the methods recorded in Han Shi Yi Tong,and at that time,the processing of Pinelliae Rhizoma Fermentata and the preparation of Massa Medicata Fermentata interacted with each other.After the founding of the People's Republic of China,the local experience in the preparation of Pinelliae Rhizoma Fermentata was deeply influenced by the methods in the Qing Dynasty,and the local preparation technical standards gradually became the same.Moreover,this article also explored the issues of the importance of"Pinelliae Rhizoma"and"ingredients for fermentation",the pre-treatment of Pinelliae Rhizoma,the distinction between cake-making process and fermentation process for Pinelliae Rhizoma,the amount of flour added as well as the timing of adding,the addition of Massa Medicata Fermentata powder,the role of Alum in Pinelliae Rhizoma Fermentata and so on.

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 evaluation efficacy and predictive prognostic value of alpha-fetoprotein (AFP) response in tyrosine kinase inhibitors (TKIs) in combination with PD-1 inhibitors (α-PD-1) for intermediate-to-advanced hepatocellular carcinoma (HCC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 205 patients with intermediate-to-advanced HCC who were admitted to 9 medical centers, including Mengchao Hepatobiliary Hospital of Fujian Medical University et al, from March 2020 to July 2022 were collected. There were 178 males and 27 females, aged (52±12)years. Based on AFP response at 6-8 weeks after treatment, patients were divided into the AFP response group (AFP level decreased by ≥50% compared to baseline) and the AFP no response group (AFP level decreased by <50% compared to baseline). Observation indicators: (1) AFP response evaluation of anti-tumor efficacy; (2) comparison of patient prognosis; (3) analysis of factors affecting patient prognosis. Measurement data with normal distrubution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range) and M( Q1, Q3). Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test. The Kaplan-Meier method was used to draw survival curve and calculate survival rate, and the Log-Rank test was used for survival analysis. The COX proportional risk model was used for univariate analysis and the COX stepwise regression model was used for multivariate analysis. Results:(1) AFP response evaluation of anti-tumor efficacy. Before treatment, all 205 patients were positive of AFP, with a baseline AFP level of 1 560(219,3 400)μg/L. All 205 patients were treated with TKIs in combination with α-PD-1, and the AFP level was 776(66,2 000)μg/L after 6 to 8 weeks of treatment. Of the 205 patients, 88 cases were classified as AFP response and 117 cases were classified as AFP no response. According to the response evaluation criteria in solid tumors version 1.1, the objective response rate (ORR) and disease control rate (DCR) were 42.05%(37/88) and 94.32%(83/88) in patients of the AFP response group and 16.24% (19/117) and 64.10% (75/117) in patients of the AFP no response group, showing significant differences between them ( χ2=16.846, 25.950, P<0.05). According to the modified response evaluation criteria in solid tumors, the ORR and DCR were 69.32% (61/88) and 94.32% (83/88) in patients of the AFP response group and 33.33% (39/117) and 64.10% (75/117) in patients of the AFP no response group, showing significant differences between them ( χ2=26.030, 25.950, P<0.05). (2) Comparison of patient prognosis. All 205 patients were followed up for 12.4(range, 2.4-34.0)months after treatment. The median progression free survival time and total survival time were 5.5 months and 17.8 months, respectively. The 1-year, 2-year progression free survival rates were 20.8% and 7.2%, and the 1-year, 2-year overall survival rates were 68.7% and 31.5%, respectively. The median progression free survival time, 1-year and 2-year progression free survival rates were 9.7 months, 39.6% and 14.2% in patients of the AFP response group and 3.7 months, 7.8% and 2.0% in patients of the AFP no response group, showing a significant difference in progression free survival between them ( χ2=43.154, P<0.05). The median overall survival time, 1-year and 2-year overall survival rates were not reached, 85.2% and 56.3% in patients of the AFP response group and 14.6 months, 56.3% and 14.5% in patients of the AFP no response group, showing a significant difference in overall survival between them ( χ2=33.899, P<0.05). (3) Analysis of factors affecting patient prognosis. Results of multivariate analysis showed that invasion of large blood vessels, extrahepatic metastasis, combined hepatic artery intervention therapy, and AFP response were independent factors influencing progression free survival in patients with intermediate-to-advanced HCC who were treated with TKIs in combination with α-PD-1 ( hazard ratio=1.474, 1.584, 0.631, 0.367, 95% confidence interval as 1.069-2.033, 1.159-2.167, 0.446-0.893, 0.261-0.516, P<0.05), and Eastern Cooperative Oncology Group score, invasion of large blood vessels, extrahepatic metastasis, and AFP response were independent factors influencing overall survival in patients with intermediate-to-advanced HCC who were treated with TKIs in combination with α-PD-1 ( hazard ratio= 1.347, 1.914, 1.673, 0.312, 95% confidence interval as 1.041-1.742, 1.293-2.833, 1.141-2.454, 0.197-0.492, P<0.05). Conclusions:AFP response at 6-8 weeks after treatment can effectively evaluate anti-tumor efficacy of TKIs in combination with α-PD-1 for intermediate-to-advanced HCC. AFP response is the independent factor influencing progression free survival and overall survival in patients with intermediate-to-advanced HCC who were treated with TKIs in combination with α-PD-1.

ObjectiveTo study the effect and mechanism of Yixintai on mitochondrial fission proteins in the rat model of chronic heart failure. MethodTen of 60 SD rats were randomly selected as the sham operation group， and the remaining 50 rats were subjected to ligation of the left anterior descending coronary artery for the modeling of heart failure post myocardial infarction. The successfully modeled rats were randomized into model， low-， medium-， and high-dose （1.4， 2.8， and 5.6 g·kg^-1， respectively） Yixintai， and trimetazidine （10 mg·kg^-1） groups. The rats were administrated with corresponding doses of drugs by gavage， and the rats in the model group and sham operation group were given an equal volume of normal saline by gavage for 28 consecutive days. Enzyme-linked immunosorbent assay （ELISA） was then employed to measure the levels of amino-terminal pro-B-type natriuretic peptide （NT-pro BNP）， B-type natriuretic peptide （BNP）， and adenosine triphosphate （ATP） in the serum. Color Doppler ultrasound imaging was conducted to examine the cardiac function indicators. Hematoxylin-eosin staining and Masson staining were conducted to observe the pathological changes in the heart， and Image J was used to calculate collagen volume fraction （CVF）. Transmission electron microscopy was employed to observe the ultrastructural changes of myocardial cells. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to measure the apoptosis rate of myocardial cells. Western blot was employed to determine the protein levels of mitochondrial fission protein 1 （Fis1） and mitochondrial fission factor （Mff） in the outer mitochondrial membrane of the myocardial tissue. ResultCompared with the sham operation group， the model group showed elevated levels of NT-pro BNP and BNP in the serum， decreased ATP content， left ventricular ejection fraction （LVEF）， and left ventricular fraction shortening （LVFS）， increased left ventricular end-diastolic diameter （LVIDd） and left ventricular end-systolic diameter （LVIDs）， disarrangement of myocardial cells， inflammatory cell infiltration， increased collagen fibers and CVF， damaged myocardium and mitochondria， and increased apoptosis rate of myocardial cells， and up-regulated expression of Fis1 and Mff in the cardiac tissue （P<0.01）. Compared with the model group， different doses of Yixintai and trimetazidine lowered the serum levels of NT-pro BNP and BNP （P<0.05）， increased the ATP content （P<0.05）， increased LVEF and LVFS （P<0.01）， decreased LVIDd and LVIDs （P<0.01）. Moreover， the drugs alleviated the myocardial inflammatory damage and fibrosis， reduced CVF （P<0.01）， repaired the myocardial mitochondrial structure， and decreased the apoptosis rate of myocardial cells （P<0.01）. Medium- and high-dose Yixintai and trimetazidine down-regulated the expression of Fis1 and Mff in the myocardial tissue （P<0.05）. ConclusionYixintai can improve mitochondrial structure， reduce myocardial cell apoptosis， and improve cardiac function by inhibiting the expression of Fis1 and Mff in the myocardial tissue.

Four pyrazines were isolated from the n-butanol fraction of Hypecoum erectum L. by using various chromatographic methods, including MCI gel, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified as hyperectpyrazin A (1), 1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol (2), 2-hydroxymethyl-6-methylpyrazin (3) and pyrazine-2-carboxylic acid (4) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, MS, etc.). The absolute configuration of compound 2 was determined by using the Mo₂(OAc)₄ induced CD analysis for the first time. Compound 1 was a new compound, compounds 2-4 were isolated from H. erectum for the first time. Compounds 1-4 were evaluated for their inhibition against acetylcholinesterase and nitric oxide generation induced by lipopolysaccharide-RAW264.7 macrophage cells. At a concentration of 50 μmol·L^-1, compounds 2 and 4 displayed inhibitory effects on acetylcholinesterase with the inhibition rates of 44.40% and 43.99%, respectively.