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.

This article systematically reviews the characteristics and trends of the writing, editing, publication and promotion of physiology textbooks in China from the late 19th century to the present, focusing on the introduction, development and innovation of Chinese physiology textbooks. The development of physiology textbooks in China is divided into four main stages: the introduction and initial development of physiology textbooks from the late 19th century to 1925; the localization and diversification of textbooks from 1926 to 1949, after the establishment of the Chinese Physiological Society; the exploratory phase of textbook construction after the founding of the People's Republic of China from 1949 to 1976; the formation and innovation of the textbook development process from 1977 to the present, following the restoration of the college entrance examination. For each phase, the article not only records the historical development of physiology textbooks, but also analyzes the evolution of their content, writing styles and the interaction with the social and political contexts. The article summarizes the characteristics and experiences of all these four phases. Special attention is given to the comprehensive statistical analysis of physiology textbooks published since the restoration of the college entrance examination and Economic Reform and Opening-up in 1977, revealing the changes in the number, publication trends and academic features of textbooks during this period. Finally, the article presets the future development of physiology textbooks in China, proposing that textbook writing should integrate aspects such as ideological and political education, medical humanities, basic and clinical medicine, health education, scientific research and international exchange and collaboration. The article also advocates for the application of new technologies and methods, such as artificial intelligence, virtual teaching models and knowledge graphs, to support "personalized learning". This research provides a systematic reference for the study of the history of medical education and offers theoretical support for the future innovation of physiology textbook in China.
Humans ; China ; History, 19th Century ; History, 20th Century ; History, 21st Century ; Physiology/education* ; Textbooks as Topic/history*

The neurophysiological mechanisms by which exercise improves cognitive function have not been fully elucidated. A comprehensive and systematic review of current domestic and international neurophysiological evidence on exercise improving cognitive function was conducted from multiple perspectives. At the molecular level, exercise promotes nerve cell regeneration and synaptogenesis and maintains cellular development and homeostasis through the modulation of a variety of neurotrophic factors, receptor activity, neuropeptides, and monoamine neurotransmitters, and by decreasing the levels of inflammatory factors and other modulators of neuroplasticity. At the cellular level, exercise enhances neural activation and control and improves brain structure through nerve regeneration, synaptogenesis, improved glial cell function and angiogenesis. At the structural level of the brain, exercise promotes cognitive function by affecting white and gray matter volumes, neural activation and brain region connectivity, as well as increasing cerebral blood flow. This review elucidates how exercise improves the internal environment at the molecular level, promotes cell regeneration and functional differentiation, and enhances the brain structure and neural efficiency. It provides a comprehensive, multi-dimensional explanation of the neurophysiological mechanisms through which exercise promotes cognitive function.
Animals ; Humans ; Brain/physiology* ; Cognition/physiology* ; Exercise/physiology* ; Nerve Regeneration/physiology* ; Neuronal Plasticity/physiology*

Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Particle Size

OBJECTIVE: To explore clinical efficacy of different technical combinations in treating ischemic diabetic foot (DF). METHODS: A retrospective analysis was conducted on 35 patients with DF who were treated with vascular interventional opening technique, periosteal distraction technique and bone cement coverage technique from January 2024 to November 2024. They were divided into comprehensive group and periosteal distraction group according to whether the vascular interventional opening technique was used in combination or not. There were 5 patients in comprehensive group, including 4 males and 1 female, aged from 59 to 73 years old with an average of (64.40±5.46) years old;the duration of diabetes ranged from 0.17 to 30.00 years with an average of (14.63±12.02) years;the courses of DF ranged from 30 to 150 days with an average of (84.00±61.48) days;2 patients were grade 2, 2 patients were grade 3, and 1 patient was grade 4 according to Wagner classification;combined vascular interventional opening, periosteal distraction and bone cement coverage surgery for treatment. There were 30 patients in periosteal stretch group, including 22 males and 8 females, aged from 58 to 86 years old with an average of (72.63±7.84) years old;the duration of diabetes was 10.00 (6.75, 16.75) years;the courses of DF was 30.00 (15.00, 37.50) days;14 patients were grade 2, 11 patients were grade 3, and 5 patients were grade 4 according to Wagner classification; combined periosteal distraction and bone cement coverage surgery for treatment. Changes of C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT), toe skin temperature, peripheral capillary oxygen saturation (SpO₂), and visual analogue scale (VAS) for pain were compared between two groups before operation and 1 week after operation. The number of operations, healing period, healing number, toe amputation number, preoperative fever situation and the number of complications were compared between two groups. RESULTS: Both groups were followed up for at least 6 months. There were no statistically significant differences in the number of operations, healing period, toe amputation rate, wound healing rate and complications between two groups (P>0.05). Before operation, the toe skin temperature of comprehensive group (26.98±0.88) ℃ was lower than that of periosteal distraction group (28.17±1.45) ℃, and the difference was statistically significant (P<0.05);while there were no statistically significant difference in CRP, IL-6, PCT, toe SpO2 and VAS between two groups (P>0.05). At 1 week after operation, IL-6, toe skin temperature, toe SpO₂ and VAS in comprehensive group were 12.29(7.92, 22.15) pg·ml-1, (36.02±0.23) ℃, (95.80±0.84) % and(1.40±0.55) respectively, while those in periosteal distraction group were 5.49(4.36, 7.45) pg·ml^-1, (31.36±1.57) ℃, (84.53±6.38) %, (2.20±0.81);and there were statistically significant differences between two groups(P<0.05). CRP, IL-6 and VAS at 1 week after operation in both groups were decreased compared with those before operation, and the differences were statistically significant(P<0.05). The toe skin temperature and SpO₂ were increased compared with those before operation, and the differences were statistically significant(P<0.001). CONCLUSION The multi-technique combination therapy, including vascular interventional opening technique, periostealdistraction technique and bone cement covering technique, could protect each other, enhance efficacy, effectively promote the wound healing of ischemic diabetic foot ulcer, and reduce the toe amputation rate. For moderate to severe ischemic DF, the combined use of periosteal distraction and bone cement coverage techniques has a satisfactory effect. For extremely severe ischemic DF with inflow tract lesions, vascular interventional opening techniques need to be added.
Humans ; Male ; Female ; Middle Aged ; Aged ; Diabetic Foot/surgery* ; Retrospective Studies ; Aged, 80 and over ; Ischemia/surgery* ; Interleukin-6/metabolism*

Point-of-care testing (POCT), as an emerging diagnostic technology, is gradually becoming an important part of the clinical diagnostic field due to its advantages, such as ease of operation, rapid response, and portability. This paper primarily introduces two mainstream technologies in POCT: lateral flow assays and nucleic acid amplification. It covers the basic principles, applications, and quality control points in design and development of the two mainstream technologies, aiming to provide a technical reference for device manufacturers, researchers, and regulatory agencies.
Point-of-Care Testing ; Point-of-Care Systems ; Quality Control ; Equipment Design ; Nucleic Acid Amplification Techniques ; Humans

OBJECTIVE: To investigate the relationship between physical activity and genetic risk and their combined effects on the risk of developing chronic obstructive pulmonary disease. METHODS: This prospective cohort study included 318,085 biobank participants from the UK. Physical activity was assessed using the short form of the International Physical Activity Questionnaire. The participants were stratified into low-, intermediate-, and high-genetic-risk groups based on their polygenic risk scores. Multivariate Cox regression models and multiplicative interaction analyses were used. RESULTS: During a median follow-up period of 13 years, 9,209 participants were diagnosed with chronic obstructive pulmonary disease. For low genetic risk, compared to low physical activity, the hazard ratios ( HRs) for moderate and high physical activity were 0.853 (95% confidence interval [ CI]: 0.748-0.972) and 0.831 (95% CI: 0.727-0.950), respectively. For intermediate genetic risk, the HRs were 0.829 (95% CI: 0.758-0.905) and 0.835 (95% CI: 0.764-0.914), respectively. For participants with high genetic risk, the HRs were 0.809 (95% CI: 0.746-0.877) and 0.818 (95% CI: 0.754-0.888), respectively. A significant interaction was observed between genetic risk and physical activity. CONCLUSION Moderate or high levels of physical activity were associated with a lower risk of developing chronic obstructive pulmonary disease across all genetic risk groups, highlighting the need to tailor activity interventions for genetically susceptible individuals.
Humans ; Pulmonary Disease, Chronic Obstructive/epidemiology* ; Exercise ; Male ; Female ; Middle Aged ; Prospective Studies ; Aged ; Genetic Predisposition to Disease ; Risk Factors ; United Kingdom/epidemiology* ; Incidence ; Adult

Background::The Global Leadership Initiative on Malnutrition (GLIM) criteria were published to build a global consensus on nutritional diagnosis. Reduced muscle mass is a phenotypic criterion with strong evidence to support its inclusion in the GLIM consensus criteria. However, there is no consensus regarding how to accurately measure and define reduced muscle mass in clinical settings. This study aimed to investigate the optimal reference values of skeletal muscle mass index for diagnosing sarcopenia and GLIM-defined malnutrition, as well as the prevalence of GLIM-defined malnutrition in hospitalized cirrhotic patients.Methods::This retrospective study was conducted on 1002 adult patients with liver cirrhosis between January 1, 2018, and February 28, 2022, at Beijing You-An Hospital, Capital Medical University. Adult patients with a clinical diagnosis of liver cirrhosis and who underwent an abdominal computed tomography (CT) examination during hospitalization were included in the study. These patients were randomly divided into a modeling group (cohort 1, 667 patients) and a validation group (cohort 2, 335 patients). In cohort 1, optimal cut-off values of skeletal muscle index at the third lumbar skeletal muscle index (L3-SMI) were determined using receiver operating characteristic analyses against in-hospital mortality in different gender groups. Next, patients in cohort 2 were screened for nutritional risk using the Nutritional Risk Screening 2002 (NRS-2002), and malnutrition was diagnosed by GLIM criteria. Additionally, the reference values of reduced muscle mass in GLIM criteria were derived from the L3-SMI values from cohort 1. Multivariate logistic regression analysis was used to analyze the association between GLIM-defined malnutrition and clinical outcomes.Results::The optimal cut-off values of L3-SMI were 39.50 cm 2/m 2 for male patients and 33.06 cm 2/m 2 for female patients. Based on the cut-off values, 31.63% (68/215) of the male patients and 23.3% (28/120) of the female patients had CT-determined sarcopenia in cohort 2. The prevalence of GLIM-defined malnutrition in cirrhotic patients was 34.3% (115/335) and GLIM-defined malnutrition was an independent risk factor for in-hospital mortality in patients with liver cirrhosis ( Wald = 6.347, P = 0.012). Conclusions::This study provided reference values for skeletal muscle mass index and the prevalence of GLIM-defined malnutrition in hospitalized patients with liver cirrhosis. These reference values will contribute to applying the GLIM criteria in cirrhotic patients.

The paper is to establish an UPLC-MS/MS method for the simultaneous determination of 19 components in Microctis Folium from different production areas. The 50% methanol was used as extraction solvent. The Agilent ZORBAX SB C18 (150 mm × 2.1 mm, 1.8 μm) column was used; mobile phase was acetonitrile - 0.1% acetic acid with gradient elution, flow rate was 0.3 mL·min^-1, colume temperature was 30 ℃, and the injection volume was 2 μL; electrospray ionizaton source was used and detected in negative ion mode. The results showed that the established UPLC-MS/MS method could well separate the 19 components, and the methodological investigation results of 19 components were good. By means of orthogonal partial least squares discriminant analysis (OPLS-DA), 28 batches of Microctis Folium samples from different production areas can be divided into three categories, Guangdong, Guangxi and Hainan are each classified into one category, and 10 signature compounds which affecting the quality differences of different production areas were screened out. The established method is accurate, reliable, sensitive and reproducible. It can provide a basis for the establishment of the quality standard of Microctis Folium, as well as for safety and quality research.

ObjectiveTo explore whether the mechanism of Shuangshen Ningxin capsules （SSNX） in alleviating myocardial ischemia-reperfusion injury （MIRI） in rats is related to the regulation of mitochondrial fission and fusion. MethodThis study focused on Sprague Dawley （SD） rats and ligated the left anterior descending branch of the coronary artery to construct a rat model of MIRI. The rats were divided into the sham operation group， model group， SSNX group （90 mg·kg^-1） and trimetazidine group （5.4 mg·kg^-1）. The activity of superoxide dismutase （SOD） and the content of malondialdehyde （MDA） were detected by micro method. Changes in mitochondrial membrane potential （△Ψm） and the degree of mitochondrial permeability transition pore （mPTP） opening were detected by the chemical fluorescence method. The intracellular adenosine triphosphate （ATP） level was detected by the luciferase assay. The messenger ribonucleic acid （mRNA） and protein expression levels of mitochondrial fission and fusion related factors dynamin-related protein 1 （DRP1）， mitochondrial fission 1 protein （FIS1）， optic atrophy protein 1 （OPA1）， mitochondrial outer membrane fusion protein 1 （MFN1）， and MFN2 were detected by real-time polymerase chain reaction （real-time PCR） and Western blot. ResultCompared with the sham operation group， the model group showed a decrease in serum SOD activity and an increase in MDA content. The opening level of mPTP， the level of △Ψm and ATP content decreased， the protein expressions of mitochondrial fission factors DRP1 and FIS1 increased， and the protein expressions and mRNA transcription levels of fusion related factors OPA1 and MFN1 decreased. Compared with the model group，SSNX significantly increased serum SOD activity， reduced MDA content， increased intracellular ATP level and △Ψm， reduced the opening level of mPTP， downregulated the protein expressions of mitochondrial fission factors DRP1 and FIS1， and increased the mRNA transcription levels and protein expressions of fusion related factors OPA1 and MFN1. ConclusionSSNX inhibits the expressions of mitochondrial fission factors DRP1 and FIS1， and increases the expressions of fusion related factors OPA1 and MFN1， inhibiting mitochondrial fission and increasing mitochondrial fusion， thereby alleviating MIRI.