1.Staged Characteristics of Mitochondrial Energy Metabolism in Chronic Heart Failure with Heart-Yang Deficiency Syndrome and Prescription Intervention from Theory of Reinforcing Yang
Zizheng WU ; Xing CHEN ; Lichong MENG ; Yao ZHANG ; Peng LUO ; Jiahao YE ; Kun LIAN ; Siyuan HU ; Zhixi HU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(5):129-138
Chronic heart failure (CHF) is a complex clinical syndrome caused by ventricular dysfunction, with mitochondrial energy metabolism disorder being a critical factor in disease progression. Heart-Yang deficiency syndrome, as the core pathogenesis of CHF, persists throughout the disease course. Insufficiency of heart-Yang leads to weakened warming and propelling functions, resulting in the accumulation of phlegm-fluid, blood stasis, and dampness. This eventually causes Qi stagnation with phlegm obstruction and blood stasis with water retention, forming a vicious cycle that exacerbates disease progression. According to the theory of reinforcing Yang, the clinical experience of the traditional Chinese medicine (TCM) master Tang Zuxuan in treating CHF with heart-Yang deficiency syndrome, and achievements from molecular biological studies, this study innovatively proposes an integrated research framework of "TCM syndrome differentiation and staging-mitochondrial metabolism mechanisms-intervention with Yang-reinforcing prescriptions" which is characterized by the integration of traditional Chinese and Western medicine. Heart-Yang deficiency syndrome is classified into mild (Stage Ⅰ-Ⅱ), severe (Stage Ⅲ), and critical (Stage Ⅳ) stages. The study elucidates the precise correlations between the pathogenesis of each stage and mitochondrial metabolism disorders from theoretical, pathophysiological, and therapeutic perspectives. The mild stage is characterized by impaired biogenesis and substrate-utilization imbalance, corresponding to heart-Yang deficiency and phlegm-fluid aggregation. Linggui Zhugantang and similar prescriptions can significantly improve the expression of peroxisome proliferator-activated receptor gamma co-activator-1α(PGC-1α)/silent information regulator 2 homolog 1 (SIRT1) and ATPase activity. The severe stage centers on oxidative stress and structural damage, reflecting Yang deficiency with water overflow and phlegm-blood stasis intermingling. At this stage, Zhenwu Tang and Qiangxin Tang can effectively mitigate oxidative stress damage, increase adenosine triphosphate (ATP) content, and repair mitochondrial structure. The critical stage arises from calcium overload and mitochondrial disintegration, leading to the collapse of Yin-Yang equilibrium. At this stage, Yang-restoring and crisis-resolving prescriptions such as Fuling Sini Tang and Qili Qiangxin capsules can inhibit abnormal opening of the mitochondrial permeability transition pore (MPTP), reduce cardiomyocyte apoptosis rate, and protect mitochondrial function. By summarizing the characteristics of mitochondrial energy metabolism disorders at different stages of CHF, this study explores the application of the theory of reinforcing Yang in treating heart-Yang deficiency syndrome and provides new insights for the clinical diagnosis and treatment of CHF.
2.Danhong Injection Regulates Ventricular Remodeling in Rat Model of Chronic Heart Failure with Heart-Blood Stasis Syndrome via p38 MAPK/NF-κB Signaling Pathway
Zizheng WU ; Xing CHEN ; Jiahao YE ; Lichong MENG ; Yao ZHANG ; Junyu ZHANG ; Zhixi HU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(5):149-159
ObjectiveTo explore the mechanism of ventricular remodeling mediated by the p38 mitogen-activated protein kinase (MAPK)/nuclear factor kappa B (NF-κB) signaling pathway in the rat model of chronic heart failure (CHF) with heart-blood stasis syndrome, as well as the intervention effect of Danhong injection. MethodsIn vivo experiment: SPF-grade male SD rats were assigned via the random number table method into 4 groups: Sham operation, model, captopril (8.8 mg·kg-1), and Danhong injection (6.0 mL·kg-1). The model of CHF with heart-blood stasis syndrome was established by abdominal aortic constriction, and the sham operation group only underwent laparotomy without constriction. All the groups were treated continuously for 15 days. The tongue color of rats was observed. Echocardiography, hemorheology, heart mass index (HMI), and left ventricular mass index (LVMI) were measured. Hematoxylin-eosin (HE) staining and Masson staining were performed to observe the pathological and fibrotic changes of the myocardial tissue. Enzyme-linked immunosorbent assay (ELISA) was employed to quantify the levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP), interleukin-6 (IL-6), angiotensin Ⅱ (AngⅡ), tumor necrosis factor-α (TNF-α), and Creactive protein (CRP) in the serum, as well as the levels of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in the myocardial tissue. Western blot was used to quantify the protein levels of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65 in the myocardial tissue. In vitro experiment: H9C2 cardiomyocytes were treated with 1×10-6 mol·L-1 AngⅡ to establish a model of myocardial hypertrophy. H9C2 cardiomyocytes were allocated into normal, model, inhibitor + Danhong injection, Danhong injection (20 mL·L-1), and inhibitor (SB203580, 5 μmol·L-1) groups. CCK-8 assay was used to detect the viability of H9C2 cardiomyocytes. Rhodamine-labeled phalloidin staining was used to reveal the area of cardiomyocytes. Real-time PCR was performed to determine the mRNA levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). Western blot was used to assess the protein levels of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65. ResultsIn vivo experiment: Compared with the sham operation group, the model group showed purplish-dark tongue with decreased R, G, B values of the tongue surface (P<0.01), increased whole blood viscosity (at low, medium, and high shear rates) (P<0.01), decreased left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) (P<0.01), increased left ventricular end-diastolic diameter (LVIDd), left ventricular end-systolic diameter (LVIDs), and left ventricular posterior wall thickness at end-diastole (LVPWd) (P<0.01), raised LVMI and HMI (P<0.01), and elevated levels of NT-proBNP, TNF-α, IL-6, and CRP in the serum and MMP-2 and MMP-9 in the myocardial tissue (P<0.01). The HE and Masson staining of the myocardial tissue showed compensatory myocardial hypertrophy, fibrosis, and massive inflammatory cell infiltration in the model group. Additionally, the model group presented up-regulated protein levels of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65 in the myocardial tissue (P<0.01). Compared with the model group, each administration group showed increased R, G, B values of the tongue surface (P<0.05, P<0.01), decreased whole blood viscosity (at low, medium, and high shear rates) (P<0.05, P<0.01), increased LVEF and LVFS (P<0.01), decreased LVIDd, LVIDs, and LVPWd (P<0.05, P<0.01), declined LVMI and HMI (P<0.05, P<0.01), and lowered levels of NT-proBNP, TNF-α, IL-6, and CRP in the serum and MMP-2 and MMP-9 in the myocardial tissue (P<0.01). HE and Masson staining showed alleviated compensatory myocardial hypertrophy, reduced fibrosis, and decreased expression of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65 in the myocardial tissue (P<0.01). In vitro experiment: When the concentration of Danhong injection reached 20 mL·L-1, the survival rate of H9C2 cardiomyocytes was the highest (P<0.01). Compared with the normal group, the model group showed up-regulated mRNA levels of ANP and BNP (P<0.01), increased relative cell surface area (P<0.01), and raised protein levels of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65 (P<0.01). Compared with the model group, each administration group showed down-regulated mRNA levels of ANP and BNP (P<0.01), reduced relative cell surface area (P<0.05, P<0.01), and down-regulated protein levels of p-p38 MAPK/p38 MAPK and p-NF-κB p65/NF-κB p65 (P<0.05, P<0.01). ConclusionDanhong injection can regulate ventricular remodeling through the p38 MAPK/NF-κB pathway, thereby exerting a protective effect on the rat model of CHF with heart-blood stasis syndrome.
3.Impact of height-desk-chair matching intervention on viewing distance of primary school students
ZHANG Yaxin*, YAO Yuan, FENG Mian, WU Yuxuan, CHEN Guoping, TAO Fangbiao, XU Shaojun
Chinese Journal of School Health 2026;47(1):51-54
Objective:
To compare the effects of height-desk-chair matching on the viewing distance of primary school students before and after intervention, so as to provide scientific basis for the hygiene management of desks and chairs.
Methods:
From April to June 2025, a random cluster sampling method was used to select 141 third grade students from three classes equipped with adjustable desks and chairs in a primary school in Hefei City for a height-desk-chair matching intervention study. The height of students desks and chairs was adjusted according to the standard height and height range specified in the Functional Sizes and Technical Requirements of Chairs and Tables for Educational Institutions (GB/T 3976-2014), with an intervention period of one week. Before and after the intervention, eye use data were measured by using the electronic smart device "Cloud Clip", while collecting data on vision data viewing distance, time spent using eyes at close range and outdoor time, desk and chair height, and physical examination. Linear regression analysis was used to investigate the factors related to viewing distance before the intervention of height-desk-chair matching, and a paired t-test was used to analyze the difference in viewing distance before and after the intervention. A mixed effects model was used to explore the effect of height desk and chair adaptation intervention on viewing distance.
Results:
The compliance rates for desk and chair adjustments before and after the intervention were 1.4% and 18.4%, respectively, with a statistically significant difference ( χ 2=22.84, P <0.01). The viewing distance increased from (30.48±5.01) cm before intervention to (32.06±5.75) cm post intervention, with a statistically significant difference ( t=4.57, P <0.01). The proportion of students meeting the viewing distance standard increased from 33.3% to 51.1%. The linear mixedeffects model results indicated that the association between height appropriate desk and chair interventions and viewing distance was statistically significant, regardless of whether covariates such as time spent using eyes at close range and outdoor time were adjusted ( β=-1.58, 95%CI = -2.25 to -0.91; β=-1.14, 95%CI =-1.85 to -0.43, both P <0.05).
Conclusion
Height adjusted desks and chairs, which can effectively increase the viewing distance for primary school students, has positive implications for improving healthy eye care behaviors among children and adolescents.
4.Current status of research on the mechanism of action of emodin in the prevention and treatment of chronic liver diseases
Yajie CHEN ; Xin WANG ; Yunjuan WU ; Ying SU ; Yuhan WANG ; Jinxue ZHANG ; Ning YAO ; Ying QIN ; Xiaoning ZUO
Journal of Clinical Hepatology 2026;42(1):228-234
Chronic liver diseases are a group of diseases in which the liver is subjected to a variety of injuries over a long period of time, resulting in irreversible pathological changes that last longer than 6 months. Emodin (EMO) is a natural anthraquinone derivative derived from Rheum officinale, and its pharmacological effect has been extensively studied, exhibiting a variety of biological properties and involving multiple signaling molecules and pathways. Western medicine or surgical treatment is currently the main treatment regimen for chronic liver diseases, and the advance in treatment is limited by various reasons such as side effects and high costs. Due to its natural origin and efficacy, EMO has unique advantages in the treatment of chronic liver diseases and has now become a research hotspot. This article summarizes the therapeutic effect of EMO on chronic liver diseases and its mechanism, in order to provide a certain scientific basis for the traditional Chinese medicine treatment of chronic liver diseases and the development of drugs in clinical practice.
5.Mechanism of Yangjing Zhongyutang in Regulating SIRT1/PGC-1α Signaling Pathway to Promote Mitochondrial Function and Alleviate Oxidative Stress Damage in Rats with Diminished Ovarian Reserve
Ping ZHANG ; Lijuan YANG ; Shenghui CHEN ; Wenliang YAO ; Yuliang ZHOU ; Ling MA ; Huiying WU ; Yanwen XU ; Ziyan ZHOU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(7):46-55
ObjectiveTo observe the effects of Yangjing Zhongyutang (YJZYT) on mitochondrial biogenesis and oxidative stress damage mediated by the silent information regulator 1 (SIRT1)/peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1α) signaling pathway in cyclophosphamide (CTX)-induced rats with diminished ovarian reserve (DOR), and to explore its mechanism in improving ovarian reserve function and follicular development. MethodsForty-two 8-week-old female SD rats with normal estrous cycles were randomly divided into a blank control group (n=7) and a model group (n=35). Rats in the model group received a single intraperitoneal injection of CTX (90 mg·kg-1) to establish the DOR model. After modeling, estrous cycles were monitored for 7 consecutive days, and model success was confirmed based on criteria for estrous cycle disruption. After successful modeling, rats were divided into groups for intervention: estradiol valerate group (0.09 mg·kg-1), and YJZYT high-, medium-, and low-dose groups (19.98, 9.99, 5.00 g·kg-1). The blank control group and model group were given an equal volume of distilled water by gavage. All groups received daily gavage once for 4 consecutive weeks. The general state, body weight, and ovarian wet weight of rats were observed and recorded, and the ovarian organ index was calculated. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), anti-Müllerian hormone (AMH), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). Hematoxylin-eosin (HE) staining was performed to observe ovarian histomorphological changes and follicular development status. Immunofluorescence was used to detect reactive oxygen species (ROS) expression levels. Colorimetric assays were employed to measure adenosine triphosphate (ATP) and malondialdehyde (MDA) content in ovarian tissues. Quantitative Real-time polymerase chain reaction (Real-time PCR) was used to detect mitochondrial DNA (mtDNA) copy number and the mRNA expression levels of key genes including SIRT1, PGC-1α, nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (TFAM). Western blot was performed to detect the protein expression levels of SIRT1, PGC-1α, NRF1, and TFAM. ResultsCompared with the blank group, rats in the model group exhibited disrupted estrous cycles, obviously reduced body weight, and decreased ovarian index (P<0.05). Ovarian histopathology revealed cortical thinning, loose structure, and a significant reduction in both primordial and growing follicles (P<0.01). Serum FSH and LH levels were significantly elevated (P<0.01), while E2 and AMH levels were obviously reduced (P<0.05, P<0.01). ATP content and mtDNA copy number decreased in ovarian tissue (P<0.01), ROS expression increased, MDA levels rose, while SOD and GSH-Px activities obviously decreased (P<0.05, P<0.01), mRNA and protein expression levels of SIRT1, PGC-1α, NRF1, and TFAM were obviously downregulated (P<0.05, P<0.01). After treatment, compared with the model group, body weight and ovarian index obviously recovered in rats administered various doses of YJZYT (P<0.05), serum E2 and AMH levels increased, while FSH and LH levels obviously decreased (P<0.05, P<0.01), ovarian tissue ATP content and mtDNA copy number were up-regulated, ROS and MDA levels decreased, and antioxidant enzymes SOD and GSH-Px activity obviously increased (P<0.05, P<0.01), Gene and protein expression levels related to the SIRT1/PGC-1α /NRF1/TFAM signaling pathway were obviously up-regulated compared to the model group (P<0.05, P<0.01), HE staining revealed that ovarian structure gradually recovered to integrity in all treatment groups, with a obviously increase in the number of primordial and growing follicles (P<0.05, P<0.01). Granulosa cells were neatly arranged, indicating marked improvement in ovarian function. ConclusionYJZYT may improve ovarian function and follicular development in rats with diminished ovarian reserve by activating the SIRT1/PGC-1α signaling pathway, promoting mitochondrial biogenesis, enhancing mitochondrial function, and alleviating oxidative stress damage.
6.Mechanism of Huangqin decoction in improving ulcerative colitis based on the gut microbiota-tryptophan metabolism-aryl hydrocarbon receptor axis
Ying CHEN ; Rong XU ; Yao HE ; Ying LI ; Zhiyu ZHANG ; Zhijiu WU
China Pharmacy 2026;37(9):1173-1179
OBJECTIVE To investigate the mechanism of Huangqin decoction in improving ulcerative colitis (UC) through the gut microbiota-tryptophan metabolism-aryl hydrocarbon receptor (AhR) axis. METHODS Mice were randomly divided into normal group (normal saline), model group (normal saline), microbiota depletion-model group (normal saline), microbiota depletion-Huangqin decoction group (9.1 g/kg, by crude drug, similarly hereinafter), Huangqin decoction group and mesalazine group (positive control group, 0.4 g/kg), with 6 mice in each group. Microbiota depletion was achieved by providing free access to a mixed antibiotics for 10 days. The UC model was induced by administering 2.5% dextran sulfate sodium solution for 7 days. After successful modeling, each treatment group received corresponding drugs or normal saline intragastrically once daily for 10 days. After the final administration, body weight change ratio, disease activity index (DAI) score, and colon length were evaluated; colon pathological changes were observed; serum levels of interleukin-6 (IL-6), IL-10, IL-22, and tumor necrosis factor-α (TNF-α) were measured; the expressions of Occludin, zonula occluden-1 (ZO-1), and AhR in colon tissue were detected; fecal samples were subjected to high-throughput sequencing to analyze targeted tryptophan metabolomics. RESULTS Compared with the model group, Huangqin decoction group showed reduced infiltration of inflammatory cells in the colon tissue and restoration of the intestinal mucosal structure. Body weight change ratio, colon length, serum content of IL-10, the expressions of Occludin, ZO-1 and AhR in colon tissue and the contents of tryptophan metabolites indole-3-propionic acid (IPA), N -acetylserotonin (NAS) and indole-3-acetic acid (IAA) were all significantly increased ( P <0.05); DAI score, serum levels of IL-6, TNF-α, and IL-22 and the content of tryptophan metabolite indole-3-ethanol were significantly decreased ( P <0.05); gut microbiota structure was improved, with increased relative abundances of beneficial bacteria such as Lactobacillus , and decreased relative abundances of pathogenic bacteria such as Escherichia-Shigella . However, after antibiotic-induced microbiota depletion, although Huangqin decoction significantly increased the content of NAS in the feces of mice, the expression of AhR protein in colon tissue did not increase concurrently. CONCLUSIONS Huangqin decoction can repair the intestinal mucosal barrier in UC mice by regulating the gut microbiota and promoting the production of IPA and IAA, thereby activating AhR. This suggests that an intact gut microbiota is an important prerequisite for Huangqin decoction to exert its AhR-regulating effects.
7.Association of polychlorinated biphenyl exposure with platelet parameters across different glycemic states: The moderating role of a healthy lifestyle
Zhuo CHEN ; Huilin LOU ; Taimeng CHEN ; Fangyuan LIN ; Xueyan WU ; Yao GUO ; Haoran XU ; Mengke CHENG ; Peihan CHEN ; Yilin ZHOU ; Zhenxing MAO ; Xin TANG
Journal of Environmental and Occupational Medicine 2026;43(5):535-541
Background Platelet parameters are important indicators of cardiovascular risk, and environmental pollutants such as polychlorinated biphenyls (PCBs) may impair platelet function through oxidative stress. Objective To investigate the differential effects of single and mixed exposure to PCBs on platelet parameters among individuals with normal glucose tolerance (NGT), impaired fasting glucose (IFG), and type 2 diabetes mellitus (T2DM), and to evaluate the potential modifying role of a healthy lifestyle. Methods This study included 2249 participants (including 707 with NGT, 759 with IFG, and 783 with T2DM). Plasma PCB concentrations were measured using triple quadrupole gaschromatography-tandem mass spectrometry. Generalized linear regression was used to assess the associations between individual PCB congeners and platelet parameters. Quantile g-computation (QGC) and Bayesian kernel machine regression (BKMR) models were used to evaluate the overall effects of PCBs mixture exposure on platelet parameters across different glycemic states, as well as its interaction with healthy lifestyle score (HLS). Results Generalized linear regression analyses showed significant differences in the effects of PCBs on platelet parameters across different glycemic states (P<0.05). After adjusting for confounders, PCBs mixture exposure was significantly associated with lower platelet counts (PLT) in individuals with NGT (b=−10.60, 95%CI: −16.48, −4.71) and IFG (b=−12.91, 95%CI: −18.90, −6.92), whereas no significant association was observed in individuals with T2DM (P=0.051). Mean platelet volume (MPV) and platelet-large cell ratio (P-LCR) increased significantly with higher PCBs exposure levels across all three groups (P<0.05). BKMR analysis showed a positive association between PCBs mixture exposure and P-LCR, with the strongest association observed in the NGT group. Furthermore, a significant interaction was observed between HLS and PCBs mixture exposure, and a higher HLS attenuated the effects of PCBs on P-LCR. Conclusion Glycemic glycemic states may modify the effects of PCBs on platelets. Individuals with NGT appear more sensitive to PCBs exposure, whereas the T2DM state may attenuate this effect. Moreover, healthy lifestyles, including not smoking, moderate alcohol consumption, maintaining moderate-to-high physical activity, a healthy diet, and an appropriate body mass index (BMI), may mitigate the adverse effects of most PCBs on platelet parameters.
8.Association of polychlorinated biphenyl exposure with platelet parameters across different glycemic states: The moderating role of a healthy lifestyle
Zhuo CHEN ; Huilin LOU ; Taimeng CHEN ; Fangyuan LIN ; Xueyan WU ; Yao GUO ; Haoran XU ; Mengke CHENG ; Peihan CHEN ; Yilin ZHOU ; Zhenxing MAO ; Xin TANG
Journal of Environmental and Occupational Medicine 2026;43(5):535-541
Background Platelet parameters are important indicators of cardiovascular risk, and environmental pollutants such as polychlorinated biphenyls (PCBs) may impair platelet function through oxidative stress. Objective To investigate the differential effects of single and mixed exposure to PCBs on platelet parameters among individuals with normal glucose tolerance (NGT), impaired fasting glucose (IFG), and type 2 diabetes mellitus (T2DM), and to evaluate the potential modifying role of a healthy lifestyle. Methods This study included 2249 participants (including 707 with NGT, 759 with IFG, and 783 with T2DM). Plasma PCB concentrations were measured using triple quadrupole gaschromatography-tandem mass spectrometry. Generalized linear regression was used to assess the associations between individual PCB congeners and platelet parameters. Quantile g-computation (QGC) and Bayesian kernel machine regression (BKMR) models were used to evaluate the overall effects of PCBs mixture exposure on platelet parameters across different glycemic states, as well as its interaction with healthy lifestyle score (HLS). Results Generalized linear regression analyses showed significant differences in the effects of PCBs on platelet parameters across different glycemic states (P<0.05). After adjusting for confounders, PCBs mixture exposure was significantly associated with lower platelet counts (PLT) in individuals with NGT (b=−10.60, 95%CI: −16.48, −4.71) and IFG (b=−12.91, 95%CI: −18.90, −6.92), whereas no significant association was observed in individuals with T2DM (P=0.051). Mean platelet volume (MPV) and platelet-large cell ratio (P-LCR) increased significantly with higher PCBs exposure levels across all three groups (P<0.05). BKMR analysis showed a positive association between PCBs mixture exposure and P-LCR, with the strongest association observed in the NGT group. Furthermore, a significant interaction was observed between HLS and PCBs mixture exposure, and a higher HLS attenuated the effects of PCBs on P-LCR. Conclusion Glycemic glycemic states may modify the effects of PCBs on platelets. Individuals with NGT appear more sensitive to PCBs exposure, whereas the T2DM state may attenuate this effect. Moreover, healthy lifestyles, including not smoking, moderate alcohol consumption, maintaining moderate-to-high physical activity, a healthy diet, and an appropriate body mass index (BMI), may mitigate the adverse effects of most PCBs on platelet parameters.
9.Analysis of T7 RNA Polymerase: From Structure-function Relationship to dsRNA Challenge and Biotechnological Applications
Wei-Chen NING ; Yu HUA ; Hui-Ling YOU ; Qiu-Shi LI ; Yao WU ; Yun-Long LIU ; Zhen-Xin HU
Progress in Biochemistry and Biophysics 2025;52(9):2280-2294
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.
10.Acceptance and commissioning testing of multiparametric imaging using the big bore dual-source CT simulator for radiotherapy
Meijiao WANG ; Yi DU ; Kaining YAO ; Zhongsu FENG ; Jixiang CHEN ; Hao WU ; Kaixuan LI ; Haizhen YUE
Chinese Journal of Radiological Health 2025;34(5):764-769
Objective To evaluate the accuracy of multiparametric imaging on the dual-source CT through acceptance and commissioning testing, and to provide a reference for standardized clinical application. Methods Both the adult and pediatric dual-source CT scanning modes were used to scan the electron density phantom, and identical multiparametric image reconstruction tasks were performed, including the conventional CT images, the mixed CT images, the virtual monoenergetic images, the iodine images, the electron density images, and the effective atomic number images. Results In the adult scanning mode, the virtual monoenergetic CT numbers showed the greatest difference for the cortical bone (


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