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 compare the chemical constituents in traditional decoction and formula granule decoction of classical famous prescription Wendan Decoction.METHODS The HPLC fingerprints were established,after which the contents of adenosine,synephrine,liquiritin,naringin,hesperidin,6-gingerol and adenosine cyclophosphate were determined,cluster analysis,principal component analysis and multidimensional scaling analysis were adopted in the investigation of component differences,and the equivalent of formula granules was adjusted.RESULTS The similarities of HPLC fingerprints for 10 batches of traditional decoctions were higher than those of HPLC fingerprints for 9 batches of formula granule decoctions(P＜0.01).Adenosine,synephrine,liquiritin,hesperidin and cyclic adenosine monophosphate demonstrated higher contents in traditional decoctions than those in formula granule decoctions(P＜0.05),6-gingerol displayed lower content than that in the latter produced by manufacturers A,C(P＜0.05),which was higher than that in the latter produced by manufacturer B(P＜0.01).Various batches of traditional decoctions and formula granule decoctions could be obviously distinguished,adenosine,synephrine and hesperidin exhibited great influences on the classification of principal component analysis,and the quality of formula granule decoctions produced by manufacturer C was closer to that of traditional decoctions.After equivalent correction,the contents of various constituents in formula granule decoctions produced by manufacturers A,C showed no significant differences as compared with those in traditional decoction(P＞0.05).CONCLUSION The formula granules of Wendan Decoction from different manufacturers exist quality differences,so the preparation process and extraction process of this preparation should be optimized to improve quality,and equivalent ratio should be adjusted according to actual requirements to ensure its scientific and rational clinical application.

Aim To predict the mechanism of action of ginsenoside Rg1(G-Rg1)paired with hirudin in the treatment of myocardial fibrosis in acute myocardial in-farction(AMI)based on the network pharmacology ap-proach,and to validate it by in vivo and in vitro experi-ments.Methods The corresponding targets of G-Rg1 and Hirudin were collected using SwissTargetPredic-tion,TargetNet,ETCM and ChEMBL databases,and the targets related to AMI and myocardial fibrosis were collected using GeneCards,OMIM and DisGeNET da-tabases.The drug-disease intersection targets were subjected to protein-protein interaction network(PPI)network analysis,gene ontology(GO)functional en-richment analysis and kyoto encyclopedia of genomes(KEGG)pathway enrichment analysis.Key targets and pathways were validated using an AMI mouse mod-el induced by ligation of the anterior descending branch of the left coronary artery in mice versus a hypoxia-in-duced injury model of human cardiac microvascular en-dothelial cells(HCMECs).Results G-Rg1 paired with hirudin had 229 drug targets,816 AMI and myo-cardial fibrosis disease targets,and 65 intersecting tar-gets.PPI analysis showed that tumor necrosis factor(TNF),interleukin-1[3(IL-1 β),transforming growth factor beta-1(TGF-β1),nuclear factor kappa-B(NF-κB),and interleukin-6(IL-6)might be the core tar-gets of G-Rg1 paired with Hirudin in the treatment of post-MI myocardial fibrosis;KEGG was enriched for a total of 141 pathways involving endocrine and metabo-lism,inflammation,and immunity,mainly TNF signa-ling pathway,PI3K/Akt signaling pathway and TGF-βsignaling pathway.In vivo experiments confirmed that G-Rg1 paired with hirudin attenuated myocardial fibro-sis after AMI in mice,and down-regulated the expres-sion of TNF-α,IL-1β,NF-κB,TGF-β1,and Smad2/3 proteins in myocardial tissues.In vitro experiments confirmed that G-Rg1 paired with Hirudin inhibited cellular NF-κB/TGF-β1 pathway,reduced hypoxia-in-duced cellular TNF-α and IL-1β expression,and su-perimposed NF-κB inhibitor significantly reduced IL-1 β expression and attenuated cellular inflammatory re-sponse.Conclusions G-Rg1 with Hirudin treats post-MI myocardial fibrosis by regulating TNF-α,IL-1 β and other targets and NF-KB/TGF-β1 pathway,reflecting its multi-pathway and multi-target action characteris-tics,and providing a pharmacological basis for the treatment of post-MI myocardial fibrosis with G-Rg1 with Hirudin.

Objective To explore the changes of durability properties of reusable surgical gowns when used in dry and wet conditions.Methods Reusable surgical gowns made of single-layer polyester fiber or 3-layer composite material were selected as test samples,and a Martindale abrasion and pilling tester was used as the basic test platform and modified to form fixtures suitable for the wet state environment.The reusable surgical gowns underwent abrasion experiments in wet and dry conditions to observe the changes in their fiber structure,and were subjected to water penetration resistance and swelling strength tests.Results Visually the reusable surgical gowns had few changes of the microscopic textile fiber structure in dry and wet conditions,and the gowns made of single-layer polyster fiber gained advantages over the outer layers of those of 3-layer composite material in abrasion resistance with the same friction cycles.In dry and wet conditions,the hydrostatic pressure values of the gowns of single-layer polyster fiber gradually decreased with the increase of the degree of abrasion,which were always lower than those of the gowns of 3-layer composite material;the swelling strength of the gowns of single-layer polyster fiber was always greater than that of the gowns of 3-layer composite material,which decreased with the deterioration of the wear more significantly than that of the gowns of 3-layer composite material.Conclusion The reusable surgical gowns made of single-layer polyester fiber or 3-layer composite material have few differences in durability and protective properties at the early stages of ablation in dry and wet conditions.The durability of the gowns decreases as the degree of wear increases,while the trend of the decrease is slowing down until the fabric breaks down and completely loses its barrier effect.[Chinese Medical Equipment Journal,2025,46(6):28-33]

Objective:Exploring the role and mechanism of CHMP4C in regulating necroptosis during gastric can-cer development and progression.Method:The expression of CHMP4C in pan-cancer was analyzed by bioinformatics methods,and the expression of CHMP4C was detected in human normal gastric epithelial cells and GC cell lines by RT-qPCR and Western blot.Overexpression or knockdown of CHMP4C was performed in GC cell lines,and the effects of CHMP4C on the growth and proliferation of GC cells were detected using CCK-8 and clone formation assays.The CCK-8 experiment and Hoechst/PI double staining experiment were used to detect the changes in GC cell mortality and PI positive cell ratio after treatment with the necroptsis inducer TSZ or inhibitor necrostatin-1(Nec-1).Western blot assay was used to detect the protein and phosphorylation levels of RIPK1,RIPK3,and MLKL in GC cells.Result:CHMP4C was upregulated in GC tissues and cells.The CCK-8 and clone formation experiments showed that overex-pression of CHMP4C significantly improved the proliferation ability and colony formation efficiency of GC cells,while knockdown of CHMP4C significantly weakened GC cells.Moreover,the results of CCK-8 and Hoechst 33342/PI double staining experiments showed that upregulated CHMP4C could inhibit TSZ induced GC cell death;Nec-1 can reverse the decrease in GC cell viability caused by CHMP4C knockdown.Western blot experiment showed that the levels of p-RIPK1,p-RIPK3,and p-MLKL were significantly decreased in overexpressing cells,while they were increased in knockdown cells.After treatment with Nec-1,the expression levels of these three proteins decreased in knockdown cells.Conclusion:CHMP4C may promote GC progression by negatively regulating necroptosis through inhibiting the phosphorylation of the RIPK1/RIPK3/MLKL signaling pathway,suggesting that it is expected to be a potential target for GC therapy.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

This article summarizesd Professor Li Zhigang's experience in treating limb dysfunction after acute disseminated encephalomyelitis(ADEM)by acupuncture.Prof.Li respected the classical theory of Chinese medicine,which is to seek the root cause of the disease,clarified the disease mechanism of"deficiency of Yangming leads to longitudinal tendons and unfavorable belt veins",and followed the principle of"treating flaccidity syndrome only by taking advantage of Yangming",and combined with the morbidity characteristics of ADEM that occurs in children,emphasized the important influence of regulating the root of innate and acquired in the treatment of the disease.The importance of regulating the essence of congenital and acquired constitution in the treatment of this disease was emphasized,taking into account the importance of regulating the mind and spirit.The main acupoints of Yangming Stomach Meridian,Large Intestine Meridian,Spleen Meridian,and Governor Vessel,together with the five main points of the lower limbs and the main points of water-inducing,all together play the role of tonifying the middle energizer,benefiting the essence and filling in the marrow,and strengthening the muscles and bones.

Fucoidan(FUC)is a natural seaweed-derived drug.Previously,our experiments have shown that FUC can significantly inhibit the cell viability of human osteosarcoma 143B cells and induce cell death,but the mechanism remains unclear.Ferroptosis,a novel form of cell death,has emerged as an important target for tumor therapy.This study aims to investigate whether FUC induces ferroptosis of 143B cells and elucidate its underlying molecular mechanisms.CCK-8 and LDH assays result showed that FUC(10,100,400 μg/mL)significantly reduced cell viability of 143B cells and induced cell death.Calce-in-AM staining,FeRhoNox-1 staining,and C11 BODIPY 581/591 staining indicated that FUC obviously increased the levels of labile iron pool(LIP),Fe2+,and lipid reactive oxygen species(Lip ROS)in 143B cells.Chemical colorimetric analysis revealed that FUC markedly decreased intracellular Glutathi-one(GSH)contents.Real-time quantitative PCR showed that FUC dramatically reduced the mRNA lev-els of ferroptosis-related factors solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4),while increasing the mRNA levels of prostaglandin endoperoxide synthase 2(PTGS2)and acyl-CoA synthetase long-chain family member 4(ACSL4).Western blotting analysis demonstrated that FUC significantly reduced the protein levels of SLC7A11 and GPX4,and the ratios of p-PI3K/PI3K,p-AktSer473/Akt,and p-AktThr308/Akt,but increased the protein level of ACSL4.Immunofluorescence staining showed that FUC obviously inhibited the nuclear translocation of p-AktSer473.The ferroptosis in-hibitor ferrostatin-1(Fer-1)and iron chelator deferoxamine(DFO)remarkably suppressed cell death in-duced by FUC in 143B cells.Additionally,the PI3K/Akt pathway activator 740Y-P significantly inhibi-ted FUC-induced iron overload and lipid peroxidation in 143B cells,and restored the protein levels of SLC7A11 and GPX4.In conclusion,FUC can induce ferroptosis of 143B cells by inhibiting the PI3K/Akt signaling pathway,which may be a potential target for the prevention and treatment of osteosarcoma.

Aim To design and synthesize a series of glycyrrhetinic acid derivatives by using glycyrrhetinic acid as the parent nucleus,screen their antitumor activ-ities,and investigate the in vitro and in vivo antitumor effects and mechanisms of the most active compound.Methods MTT assay was used to screen for the com-pound with the most potent antitumor activity.MTT as-say,wound healing assay,colony formation assay and Transwell migration assay were used to evaluate the effects of the compound on tumor cell viability and mi-gration.Flow cytometry was employed to assess the im-pact of the compound on tumor cell cycle progression and apoptosis.Western blot was conducted to verify the effects on the expression of pro-apoptotic proteins Bax,caspase-3 and cleaved caspase-3.A mouse model of hepatocellular carcinoma ascites tumor was estab-lished to examine the antitumor effects of the compound in vivo.Results Compound C22 was identified as having the most significant inhibitory effect on hepato-cellular carcinoma cells.C22 inhibited the viability and migration of hepatocellular carcinoma cells in a time and concentration-dependent manner.C22 upreg-ulated the expression of pro-apoptotic proteins Bax,caspase-3 and cleaved caspase-3 in hepatocellular car-cinoma cells,induced apoptosis,and arrested the cell cycle in the G0/G1 and S phases.C22 significantly re-duced the growth of mouse hepatocellular carcinoma as-cites tumors and prolonged survival.Conclusion Glycyrrhetinic acid derivative C22 significantly inhibits the viability and migration of hepatocellular carcinoma cells in vitro and in vivo,and induces cell cycle arrest and apoptosis.

Objective:To investigate the predictive value of anti-Müllerian hormone (AMH) on the outcome of microscopic testicular sperm extraction (micro-TESE) in patients with non-mosaic Klinefelter syndrome (KS) of the clinical data and to identify effective predictors for successful micro-TESE.Methods:A retrospective case-control study was conducted on the clinical data of 118 non-mosaic KS patients treated at the Center for Reproductive Medicine of the First Affiliated Hospital of Zhengzhou University between May 2018 and September 2023. Patients were divided into two groups based on whether sperm were successfully retrieved via micro-TESE: the sperm retrieved group ( n=45) and the no sperm retrieved group ( n=73). Differences between the two groups were compared, and multivariate logistic regression analysis was used to identify factors influencing sperm retrieval. Changes in testicular volume and sex hormone levels before and after surgery were also assessed. Results:The sperm retrieval rate was 38.1% (45/118). Patients in the sperm retrieved group were significantly younger [(26.93±3.80) years] than those in the no sperm retrieved group [(28.27±3.92) years, P=0.029], and the AMH level was significantly higher [0.44 (0.18, 1.13) μg/L] than that in the no sperm retrieved group [0.10 (0.03, 0.22) μg/L, P<0.001]. AMH was identified as an independent predictor of micro-TESE outcome in non-mosaic KS patients ( OR=7.867, 95% CI: 2.727-27.242, P=0.001). The area under the receiver operating characteristic curve was 0.802 (95% CI: 0.722-0.883), and the optimal reference threshold for AMH was ≥0.265 μg/L. Postoperatively, testosterone levels decreased significantly by a median of 0.27 μg/L ( P=0.019), while luteinizing hormone levels increased by a median of 2.08 U/L ( P=0.049), with a more significant decline in testosterone levels observed in the no sperm retrieved group by a median of 0.29 μg/L ( P=0.022). Conclusion:AMH can predict successful micro-TESE in non-mosaic KS patients, with higher AMH levels indicating a higher likelihood of success.