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 study aims to investigate the effect of salvianolic acid B (Sal B), the active ingredient of Salvia miltiorrhiza, on H9C2 cardiomyocytes injured by oxygen and glucose deprivation/reperfusion (OGD/R) through regulating mitochondrial fission and fusion. The process of myocardial ischemia-reperfusion injury was simulated by establishing OGD/R model. The cell proliferation and cytotoxicity detection kit (cell counting kit-8, CCK-8) was used to detect cell viability; the kit method was used to detect intracellular reactive oxygen species (ROS), total glutathione (t-GSH), nitric oxide (NO) content, protein expression levels of mitochondrial fission and fusion, apoptosis-related detection by Western blot. Mitochondrial permeability transition pore (MPTP) detection kit and Hoechst 33342 fluorescence was used to observe the opening level of MPTP, and molecular docking technology was used to determine the molecular target of Sal B. The results showed that relative to control group, OGD/R injury reduced cell viability, increased the content of ROS, decreased the content of t-GSH and NO. Furthermore, OGD/R injury increased the protein expression levels of dynamin-related protein 1 (Drp1), mitofusions 2 (Mfn2), Bcl-2 associated X protein (Bax) and cysteinyl aspartate specific proteinase 3 (caspase 3), and decreased the protein expression levels of Mfn1, increased MPTP opening level. Compared with the OGD/R group, it was observed that Sal B had a protective effect at concentrations ranging from 6.25 to 100 μmol·L^-1. Sal B decreased the content of ROS, increased the content of t-GSH and NO, and Western blot showed that Sal B decreased the protein expression levels of Drp1, Mfn2, Bax and caspase 3, increased the protein expression level of Mfn1, and decreased the opening level of MPTP. In summary, Sal B may inhibit the opening of MPTP, reduce cell apoptosis and reduce OGD/R damage in H9C2 cells by regulating the balance of oxidation and anti-oxidation, mitochondrial fission and fusion, thereby providing a scientific basis for the use of Sal B in the treatment of myocardial ischemia reperfusion injury.

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.

Objective　To collect data of fungi isolated from a fungus monitoring network in Hainan Province from 2013 to 2022, and analyze the drug resistance characteristics of Candida and the results of serological tests, with an aim to provide a basis for clinical diagnosis and treatment. Methods　In accordance with the National Fungal Drug Resistance Monitoring Network technical scheme, the qualifying fungal data were extracted from the microbial identification system database using SQL language, and the data information was then analyzed, with statistical processing done using SPSS 26.0 software. Results　Among 5 503 fungal isolates from clinical specimens between 2013 and 2022, cervical orifice secretions accounted for 30.37%(1 671 strains), mid-stream urine for 23.55%(1 296 strains), lower respiratory tract specimens for 25.24% (1 389 strains)[(sputum for 20.37%(1 121 strains) and alveolar lavage fluid for 4.87%(268 strains)], wound pus for 9.59%(528 strains), ascites for 5.60%(308 strains), blood for 3.67%(202 strains), cerebrospinal fluid for 0.38%(21 strains), and joint fluid for 0.04%(2 strains), with the highest number of strains isolated in 2022 and the lowest in 2013, the 2022 figure is about 2.6 times that of 2013. Among yeast-like fungi, Candida albicans had the highest proportion with 3 312 strains accounting for 60.2%; The highest resistance rate of Candida albicans was to fluconazole at 16.7%, with 2.5% being non-wild type (NWT) for amphotericin B; Candida tropicalis had the highest rate of resistance to fluconazole at 36.0%, with NWT at 41.1% for fluconazole and 3.1% for amphotericin B; Candida glabrata had a resistance rate to fluconazole of 2.8%, dose-dependent susceptibility (SDD) of 97.2%, NWT of 15.5% for fluconazole, and NWT of 8.6% for itraconazole; Candida parapsilosis had the highest resistance rate to fluconazole at 15.7% and and NWT of 8.3% for amphotericin B; Candida krusei had a 0.0% resistance rate to caspofungin; and Candida dubliniensis was 100.0% NWT to fluconazole. Of 70 cases of blood culture-positive specimens, 64 cases were detected by G test and 25 cases by Mn test, and the positive blood cultures were statistically significant when compared with the G test and Mn test, respectively (P<0.01). Conclusions　 Fungal serological test can make up for the deficiency of blood culture and distinguish fungal invasion and colonization, thus providing a basis for the effective control of fungal infection in clinical practice.

Objective:To investigate the impact of ionizing radiation(IR)on the structure and function of the testis and pro-vide some strategies for the prevention and treatment of IR-induced damage(IRD).Methods:Using radiation dose simulation,se-men analysis,hormone testing,electron microscopy and single-cell transcriptome sequencing,we assessed and analyzed a case of IRD.We established a mouse model of IRD to validate the results of single-cell sequencing,and investigated the specific biological mecha-nisms of IRD and potential strategies for its intervention.Results:IR at 1-2 Gy significantly reduced sperm concentration and mo-tility,which gradually recovered after 12 months but the percentage of morphologically normal sperm remained low.It also caused im-balanced levels of various steroid hormones,decreased testosterone and dehydroepiandrosterone sulfate,increased progesterone,prolac-tin,luteinizing hormone,and follicle-stimulating hormone.Electron microscopy revealed damages to the testis structure,including loss of germ cells,atrophy of the seminiferous tubules,nuclear membrane depression of the spermatocytes,mitochondrial atrophy and de-formation,and reduction of mitochondrial cristae.Single-cell sequencing indicated significant changes in the function of the Leydig cells and macrophages and disrupted lipid-related metabolic pathways after IRD.Administration of L-carnitine to the mouse model im-proved lipid metabolism disorders and partially alleviated IRD to the germ cells.Conclusion:Ionizing radiation can cause disorders of testicular spermatogenesis and sexual hormones and inhibit lipid metabolism pathways in Leydig cells and macrophages.Improving lipid metabolism can alleviate IRD to germ cells.

ObjectiveTo evaluate the expression level of DNA damage repair gene FANCI in hepatocellular carcinoma （HCC） and its relationship with prognosis， clinical stage and immune infiltration. MethodsIn this study， TCGA， GTEx， TIMER2.0， HPA database and qRT-PCR， western blot and immunohistochemistry were used to analyze the expression of FANCI in HCC and its correlation with different clinical stages； Kaplan-Meier Plotter database was used to explore the relationship between FANCI and the prognosis of HCC； the TISIDB database was used to analyze the relationship between FANCI and immune cell infiltration and immune checkpoints in HCC； the STRING database was used to detect the protein binding with FANCI； the TCGA and GTEx databases were used for GO and KEGG enrichment analysis； Cell experiments were used to explore the role of FANCI in HCC. ResultsCompared with normal tissues， the mRNA and protein expression levels of FANCI in tumor tissues were up-regulated （P<0.001）； and HCC patients with high expression of FANCI had poor prognosis （P<0.001）； the expression of FANCI in tumor tissues was positively correlated with the number of activated CD4⁺ T cells， the number of Th2 cells and the expression of immune checkpoints， and B-cell and macrophage infiltration was significantly lower in the FANCI high expression group （P<0.01）； GO and KEGG enrichment analysis showed that FANCI-related genes were enriched in various biological processes such as amino acid transmembrane transporter activity； Cell experiments showed that knockdown of FANCI could inhibit the proliferation， invasion and migration of HCC （P<0.05）. ConclusionsFANCI is highly expressed in hepatocellular carcinoma tissues， which may play a role in suppressing anti-tumor immunity and acting on pathways such as amino acid transmembrane transport， and is associated with poor prognosis. The proliferation， invasion and migration ability of hepatocellular carcinoma are inhibited after knocking down FANCI.

OBJECTIVES: To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia. METHODS: A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively. RESULTS: Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia. CONCLUSIONS The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia.
Infant, Newborn ; Humans ; Male ; Pregnancy ; Female ; Nomograms ; Retrospective Studies ; Cesarean Section ; Risk Factors ; Asphyxia Neonatorum/etiology*

The efficacy of HPV vaccine in preventing cervical cancer has been demonstrated in numerous clinical trials and clinical uses. The follow-up after clinical trials usually last for 5-6 years to evaluate the long-term efficacy, and a series of long-term follow-up studies have been conducted in some regions. The literature retrieval of HPV vaccine long term efficiency research both at home and abroad indicated that the protective efficacy of the vaccine against vaccine-type-related cervical intraepithelial neoplasia grade 2 and above is higher than 90%.
Humans ; Human Papillomavirus Viruses ; Biomedical Research ; Papillomavirus Vaccines

Objective: To evaluate the efficacy and safety of Nocardia rubra cell wall skeleton (Nr-CWS) in the treatment of persistent cervical high-risk human papillomavirus (HR-HPV) infection. Methods: A randomized, double blind, multi-center trial was conducted. A total of 688 patients with clinically and pathologically confirmed HR-HPV infection of the cervix diagnosed in 13 hispital nationwide were recruited and divided into: (1) patients with simple HR-HPV infection lasting for 12 months or more; (2) patients with cervical intraepithelial neoplasia (CIN) Ⅰ and HR-HPV infection lasting for 12 months or more; (3) patients with the same HR-HPV subtype with no CINⅡ and more lesions after treatment with CINⅡ or CIN Ⅲ (CINⅡ/CIN Ⅲ). All participants were randomly divided into the test group and the control group at a ratio of 2∶1. The test group was locally treated with Nr-CWS freeze-dried powder and the control group was treated with freeze-dried powder without Nr-CWS. The efficacy and negative conversion rate of various subtypes of HR-HPV were evaluated at 1, 4, 8, and 12 months after treatment. The safety indicators of initial diagnosis and treatment were observed. Results: (1) This study included 555 patients with HR-HPV infection in the cervix (included 368 in the test group and 187 in the control group), with an age of (44.1±10.0) years. The baseline characteristics of the two groups of subjects, including age, proportion of Han people, weight, composition of HR-HPV subtypes, and proportion of each subgroup, were compared with no statistically significant differences (all P>0.05). (2) After 12 months of treatment, the effective rates of the test group and the control group were 91.0% (335/368) and 44.9% (84/187), respectively. The difference between the two groups was statistically significant (χ²=142.520, P<0.001). After 12 months of treatment, the negative conversion rates of HPV 16, 18, 52, and 58 infection in the test group were 79.2% (84/106), 73.3% (22/30), 83.1% (54/65), and 77.4% (48/62), respectively. The control group were 21.6% (11/51), 1/9, 35.1% (13/37), and 20.0% (8/40), respectively. The differences between the two groups were statistically significant (all P<0.001). (3) There were no statistically significant differences in vital signs (body weight, body temperature, respiration, pulse rate, systolic blood pressure, diastolic blood pressure, etc.) and laboratory routine indicators (blood cell analysis, urine routine examination) between the test group and the control group before treatment and at 1, 4, 8, and 12 months after treatment (all P>0.05); there was no statistically significant difference in the incidence of adverse reactions related to the investigational drug between the two groups of subjects [8.7% (32/368) vs 8.0% (15/187), respectively; χ²=0.073, P=0.787]. Conclusion: External use of Nr-CWS has good efficacy and safety in the treatment of high-risk HPV persistent infection in the cervix.
Female ; Humans ; Adult ; Middle Aged ; Cervix Uteri/pathology* ; Uterine Cervical Neoplasms/pathology* ; Papillomavirus Infections/diagnosis* ; Cell Wall Skeleton ; Persistent Infection ; Powders ; Uterine Cervical Dysplasia/pathology* ; Immunotherapy ; Papillomaviridae

Objective: To determine the efficacy of eltrombopag for primary immune thrombocytopenia (ITP) in adults and the predictive factors for treatment-free response (TFR) . Methods: Clinical data of adults with ITP who received eltrombopag from June 14, 2013 to May 31, 2021 in the Hematology Department of Ruijin Hospital affiliated with Shanghai Jiao Tong University Medical College were retrospectively analyzed. The initial dose of eltrombopag was 25 mg/d, and the maximum dose was 75 mg/d; the dose was adjusted to maintain the platelet count to within 50-150×10(9)/L. Treatment was discontinued according either to the protocol, on the patient's wishes or doctor's judgment (prescription medication), or based on clinical trials. The efficacy of eltrombopag and factors for TFR among patients who achieved complete response and those who discontinued treatment were analyzed. Results: Overall, 106 patients with ITP (33 men and 73 women) were included in the study. The median age of patients was 50 (18-89) years. There were 2, 10, and 94 cases of newly diagnosed, persistent, and chronic ITP, respectively. The complete response rate was 44.3% (47/106), the response rate was 34.0% (36/106), and the overall response rate was 78.3% (83/106). Meanwhile, 83 patients who responded to treatment discontinued eltrombopag; of these, 81 patients were evaluated. Additionally, 17 patients (21.0%) achieved TFR. The median follow-up duration of patients who achieved TFR was 126 (30-170) weeks. The recurrence rate was 17.6% (3/17), and the relapse-free survival rate was 76.5%. The results of univariate analysis revealed that non-recurrence after discontinuation of other treatments for ITP (P=0.001), and platelet count and eltrombopag dose of ≥100×10(9)/L (P=0.007) and ≤25 mg/d (P=0.031), respectively, upon discontinuation of eltrombopag were predictors of TFR; these effects were attributed to prolonged effective duration of eltrombopag. Multivariate analysis showed that there was a correlation between non-recurrence and prolonged effective duration after discontinuation of other treatments for ITP (P=0.002) . Conclusion: Eltrombopag is effective for patients with ITP as it can result in TFR. Predictors for TFR include non-recurrence after discontinuation of concomitant ITP treatment, and platelet count and eltrombopag dose of ≥100 × 10(9)/L and ≤25 mg/d upon discontinuation of treatment, respectively.
Male ; Humans ; Adult ; Female ; Middle Aged ; Aged ; Aged, 80 and over ; Purpura, Thrombocytopenic, Idiopathic/diagnosis* ; Retrospective Studies ; Treatment Outcome ; China/epidemiology* ; Benzoates/therapeutic use*