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.

Objectives To investigate the relationship between self-reported occupational noise exposure and levels of plasma inflammatory cytokines in asthmatic patients. Methods A total of 910 adult asthmatic patients were selected as the study subjects, and their occupational noise exposure history and other related information were collected. The peripheral blood samples were collected from the patients, and the expression levels of plasma soluble CD14 (sCD14), complement factor D (CFD), Eotaxin-11 (CCL11), and IL-9 were determined. The relationship between self-reported occupational noise exposure and the expression levels of the four inflammatory cytokines in patients’ plasma were analyzed using multiple linear regression models. The interactions between confounding factors and self-reported occupational noise exposure were further analyzed by interaction analysis. Results The plasma CCL11, sCD14 and CFD expressions in asthmatic patients with self-reported occupational noise exposure were significantly higher than those in patients without the exposure (P<0.05). After adjusting for confounding factors, compared with patients reporting no occupational noise exposure, the plasma CFD expression was increased by 0.17 (95% CI: 0.02, 0.31) natural logarithm units in patients with self-reported occupational noise exposure. During remission, the levels of plasma CCL11 and sCD14 in asthmatic patients with self-reported occupational noise exposure were increased by 0.27 (95% CI: 0.05, 0.49) and 0.22 (95% CI: 0.02, 0.41) natural logarithm units, respectively, when compared with patients without the exposure. Interaction analysis showed that self-reported occupational noise exposure had significant multiplicative interaction with smoking or pet ownership on plasma CCL11 or CFD expressions in asthmatic patients (all P<0.05). Conclusion Self-reported occupational noise exposure is significantly associated with increased expression levels of plasma CFD, CCL11, and sCD14 in adult asthmatic patients.

ObjectiveTo investigate the acute effects of compound air pollution on children’s respiratory function. MethodsUsing panel group study design， 223 students in five classes of grade 4 from two primary schools （a， b） in Xuhui and Hongkou districts of Shanghai were randomly selected to measure pulmonary function and exhaled nitric oxide （FeNO）. The first three tests were carried out from May to June in 2020， and the fourth test was carried out from September to December in 2021. At the same time， the daily and hourly mean values of PM_2.5， PM₁₀， SO₂， NO₂， O₃ and CO was collected from the nearby air quality monitoring points of the two schools during the same period ， as well as meteorological monitoring data （temperature， humidity， wind speed and atmospheric pressure）. The linear mixed effect model was used to analyze the effects of air pollution on pulmonary function and respiratory inflammation in the summer. ResultsThe results of single pollutant model showed that PM_2.5， PM_10， SO₂ and NO₂ were positively correlated with FeNO， and the effect was reflected in lag0， lag1 and lag3 （P<0.05）. PM_2.5， PM₁₀ and NO₂ were negatively correlated with the changes of lung function FEF_25%， FEF_50%， FEF_75%， FeF_25%-75%， PEF， FVC， FEV1 and FEV1/FVC， and the effect was reflected in lag0 to lag3 days （P<0.05）. The results of the dual pollutant model showed that the concentration changes of SO₂ and NO₂ were significantly correlated with the decrease of FEV1 when combined with O₃ or PM_2.5 （P<0.01）， and the concentration changes of PM_2.5 was significantly correlated with the increase of FeNO when O₃， SO₂ and NO₂ were combined respectively （P<0.01）. The effects of the dual pollutant model were greater than the effect of PM_2.5 single pollutant model. ConclusionThe health effects of different air pollutants on children’s respiratory tract function indexes in summer are different. The combined effects of two pollutants on the lung function of children increased to different degrees. Although air pollution is light in summer， it still has an impact on children’s respiratory tract function index and inflammation index， and the combined effect of dual pollutants is more significant than that of single pollutant.

Objective To analyze the changes of vitamin D in children with Henoch-Schonlein purpura(HSP).Methods 130 children with HSP from Kunming Children's Hospital between July 2022-July 2023 were selected as the study subjects and 100 healthy children were selected during the same period as the control group.The blood samples were collected from the children with HSP and the healthy children.The content of vitamin D was measured by Kunming Kingmed Institute for Clinical Laboratory.Results The content of 25(OH)D in children with HSP was lower than that in healthy children,and the difference was statistically significant(P<0.01).The proportion of vitamin D insufficiency in children with HSP was higher than that in healthy children,and the difference was statistically significant(P<0.01).Conclusion The children with HSP are prone to vitamin D insufficiency.Vitamin D supplementation may provide a new method for the treatment of HSP.

Objective:To analyze retinal vascular parameters and distribution characteristics in Chinese population via the fully automated quantitative measurement of retinal vascular morphological parameters based on artificial intelligence technology.Methods:A cross-sectional study was performed.A total of 1 842 patients without fundus diseases who visited Beijing Tongren Hospital from January 2011 to December 2021 were included.Standardized questionnaires, blood draws and ophthalmologic examinations of enrolled subjects were conducted.Color fundus photographs centered on the optic disk of one eye of patients were collected, and a deep learning-based semantic segmentation network ResNet101-Unet was used to construct a vascular segmentation model for fully automated quantitative measurement of retinal vascular parameters.The main measurement indexes included retinal vascular branching angle, vascular fractal dimension, average vascular caliber, and average vascular tortuosity.To compare different retinal parameters between sexes, the correlation between the above parameters and ocular factors such as best corrected visual acuity, intraocular pressure, and axial length, as well as systemic factors such as sex, age, hypertension, diabetes mellitus, and cardiovascular disease was analyzed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Beijing Tongren Hospital, Capital Medical University (No.20001220). Written informed consent was obtained from each subject.Results:The model established in this study achieved an accuracy over 0.95 for both vascular and optic disk segmentation.The vascular branching angle, vascular fractal dimension, average vascular caliber, and average vascular tortuosity were (51.023±11.623)°, 1.573(1.542, 1.592), 64.124(60.814, 69.053)μm, (0.001 062±0.000 165)°, respectively.Compared with females, males had larger vascular branching angle, smaller average vascular caliber and smaller vascular tortuosity, and the differences were statistically significant (all at P<0.05). The average vascular caliber increased by 1.142 μm in people with cardiovascular disease compared to people without cardiovascular disease ( B=1.142, P=0.029, 95% CI: 0.116-2.167). The average vascular tortuosity was positively correlated with hypertension ( B=3.053×10 -5, P=0.002, 95% CI: 1.167×10 -5-4.934×10 -5) and alcohol consumption ( B=1.036×10 -5, P=0.014, 95% CI: 0.211×10 -5-1.860×10 -5) and negatively correlated with hyperlipidemia ( B=-2.422×10 -5, P=0.015, 95% CI: -4.382×10 -5-0.462×10 -5). For each 1-mm increase in axial length, there was a decrease of 0.004 in vessel fractal dimension ( B=-0.004, P<0.001, 95% CI: -0.006--0.002), a decrease of 0.266 μm in the average vessel caliber ( B=-0.266, P=0.037, 95% CI: -0.516--0.016), and a decrease of -2.45×10 -5° in the average vessel tortuosity ( B=-2.45×10 -5, P<0.001, 95% CI: -0.313×10 -5--0.177×10 -5). For each 1.0 increase in BCVA, there was an increase of 3.992° in the vascular branch angle ( B=3.992, P=0.004, 95% CI: 1.283-6.702), an increase of 0.090 in vascular fractal dimension ( B=0.090, P<0.001, 95% CI: 0.078-0.102) and a decrease of 14.813 μm in the average vascular diameter ( B=-14.813, P<0.001, 95% CI: -16.474--13.153). Conclusions:A model for retinal vascular segmentation is successfully constructed.Retinal vessel parameters are associated with sex, age, systemic diseases, and ocular factors.

OBJECTIVE To develop the evaluation system for the readability of drug instructions based on Chinese patient needs， and to provide scientific evidence for improving the readability of drug instructions in China. METHODS The literature review and expert consultation were adopted to establish the evaluation index system for the readability of drug instructions. Then， by the analytic hierarchy process， the index weight in the evaluation system was determined， and the evaluation system for the readability of drug instructions was established. Fuzzy comprehensive evaluation was used to test the evaluation system， taking drug instruction of Dexamethasone acetate cream as an example. RESULTS The evaluation system for the readability of drug instructions was established with 5 primary criteria such as text expression， numerical application， content design， behavioral suggestions， and layout design， as well as 17 sub-criteria such as easy-to-understand words and appropriately long sentences. The reliability and validity tests met the requirements. The result of 100 respondents evaluating the readability of the drug instructions of Dexamethasone acetate cream showed that the readability of drug instructions was scored as good as 4.24. CONCLUSIONS Established evaluation system for the readability of drug instructions in the study can be used to evaluate the quality and readability of drug instructions in China.

Morita therapy has been bom for more than 100 years.Inpatient Morita therapy is highly oper-able and easy to master.It can improve many refractory neuroses through four-stage treatment.But more neuroses are treated in outpatient clinics,and Morita therapy cannot be used in hospitalized patients.Therefore,the formula-tion of expert opinions on outpatient operations is particularly important.This paper is based on domestic and for-eign references,and after many discussions by domestic Morita therapy experts,and then drew up the first version of the expert opinions on operation of outpatient Morita therapy.Meanwhile the operation rule of Morita therapy in three stages of outpatient treatment was formulated:in the etiological analysis stage,under the theoretical guidance of Morita therapy,analyze the pathogenic factors,to improve treatment compliance and reduce resistance;during the operating stage,guide patients to engage in constructive and meaningful actions,realizing the achievement of letting nature take its course principle;in the cultivating character and enriching life stage,pay attention to positive infor-mation,expanding the scope and content of actions,improving the ability to adapt to complex life,and preventing recurrence caused by insufficient abilities.It will lay a foundation for the promotion of Morita therapy in domestic outpatient clinics,so that more patients with neurosis and other psychological diseases could receive characteristic Morita therapy treatment in outpatient clinics.

Objective To observe the role of dried tangerine peel in Yigong Powder improves iron metabolism and promotes red blood cell generation in anemia of chronic disease (ACD).Methods With a two-by-two factorial design,the Yigong Powder was divided into dried tangerine peel and Chenpi absent Decoction. According to the random number table method,32 zymosan-induced generalized inflammation (ZIGI) mice were randomly divided into the model group,the dried tangerine peel group,the Chenpi absent Decoction group,and the Yigong Powder group. The dried tangerine peel group,Chenpi absent Decoction group and the Yigong Powder group were given dried tangerine peel(3.083 g/kg),Chenpi absent Decoction(12.33g/kg),and Yigong Powder(15.413g/kg)by gavage to the corresponding group of mice. The model group was given an equal amount of physiological saline by gavage,and treated continuously for 7 days. After the completion of administration,the body weight of each group of mice was recorded. The hemoglobin content of each group of mice was detected using a fully automatic cell counter,the serum iron content was detected using colorimetry,the serum ferritin content was detected using enzyme-linked immunosorbent assay (ELISA),and the spleen index was calculated. The liver tissue inflammatory factors interleukin-1β (IL-1β),interleukin-6 (IL-6),tumor necrosis factor-α (TNF-α),interferon-γ (IFN-γ),interleukin-4 (IL-4),and interleukin-10 (IL-10) levels were detected using Luminex method. The mRNA expressions of liver tissue hepcidin gene (HAMP) and membrane iron transporter ( Fpn) were detected using real-time fluorescence PCR method. Results Dried tangerine peel and Chenpi absent Decoction both showed interactive effects in regulating hemoglobin,serum iron,serum ferritin content,improving spleen index,and regulating the mRNA expressions of HAMP,Fpn,as well as IL-1β and IFN-γ (P<0.05). Compared with the model group,dried tangerine peel significantly increased hemoglobin,serum iron content,and Fpn mRNA expression in ZIGI model mice,while decreasing ferritin content,spleen index,HAMP mRNA expression,and the levels of IL-1β,IL-6,TNF-α,and IFN-γ (P<0.05). Chenpi absent Decoction significantly increased serum iron content and Fpn mRNA expression in ZIGI model mice,while reducing spleen index,ferritin content,HAMP mRNA expression,and the levels of IL-1β and IFN-γ、IL-4 (P<0.05). Conclusion The effects of dried tangerine peel on inflammatory factors (IL-6 and TNF-α) and Fpn may play a key role in the improvement effects of Yigong Powder on ACD and iron metabolism.

Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to the frequency of dendritic cell subsets and expression of the costimulatory molecules CD40,CD80,CD83,and CD86. Method This was a cross-sectional study in which patients were divided into a natural history group(namely NH group),a long-term oral nucleoside analogs treatment group(namely NA group),and a plateau-arriving group(namely P group).The percentage of plasmacytoid dendritic cell and myeloid dendritic cell subsets in peripheral blood lymphocytes and monocytes and the mean fluorescence intensity of their surface costimulatory molecules were detected using a flow cytometer. Results In total,143 patients were enrolled(NH group,n = 49;NA group,n = 47;P group,n = 47).The results demonstrated that CD141/CD1c double negative myeloid dendritic cell(DNmDC)/lymphocytes and monocytes(%)in P group(0.041[0.024,0.069])was significantly lower than that in NH group(0.270[0.135,0.407])and NA group(0.273[0.150,0.443]),and CD86 mean fluorescence intensity of DNmDCs in P group(1832.0[1484.0,2793.0])was significantly lower than that in NH group(4316.0[2958.0,5169.0])and NA group(3299.0[2534.0,4371.0]),Adjusted P all<0.001. Conclusion Reduced DNmDCs and impaired maturation may be associated with the onset of the plateau phase during intermittent interferon therapy in patients with chronic hepatitis B.

Objective To explore characteristics of clinical parameters and cytokines in patients with drug-induced liver injury(DILI)caused by different drugs and their correlation with clinical indicators. Method The study was conducted on patients who were up to Review of Uncertainties in Confidence Assessment for Medical Tests(RUCAM)scoring criteria and clinically diagnosed with DILI.Based on Chinese herbal medicine,cardiovascular drugs,non-steroidal anti-inflammatory drugs(NSAIDs),anti-infective drugs,and other drugs,patients were divided into five groups.Cytokines were measured by Luminex technology.Baseline characteristics of clinical biochemical indicators and cytokines in DILI patients and their correlation were analyzed. Results 73 patients were enrolled.Age among five groups was statistically different(P=0.032).Alanine aminotransferase(ALT)(P=0.033)and aspartate aminotransferase(AST)(P=0.007)in NSAIDs group were higher than those in chinese herbal medicine group.Interleukin-6(IL-6)and tumor necrosis factor alpha(TNF-α)in patients with Chinese herbal medicine(IL-6:P<0.001;TNF-α:P<0.001)and cardiovascular medicine(IL-6:P=0.020;TNF-α:P=0.001)were lower than those in NSAIDs group.There was a positive correlation between ALT(r=0.697,P=0.025),AST(r=0.721,P=0.019),and IL-6 in NSAIDs group. Conclusion Older age may be more prone to DILI.Patients with NSAIDs have more severe liver damage in early stages of DILI,TNF-α and IL-6 may partake the inflammatory process of DILI.