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.

BACKGROUND: Temozolomide (TMZ) resistance is a significant challenge in treating glioblastoma (GBM). Collagen remodeling has been shown to be a critical factor for therapy resistance in other cancers. This study aimed to investigate the mechanism of TMZ chemoresistance by GBM cells reprogramming collagens. METHODS: Key extracellular matrix components, including collagens, were examined in paired primary and recurrent GBM samples as well as in TMZ-treated spontaneous and grafted GBM murine models. Human GBM cell lines (U251, TS667) and mouse primary GBM cells were used for in vitro studies. RNA-sequencing analysis, chromatin immunoprecipitation, immunoprecipitation-mass spectrometry, and co-immunoprecipitation assays were conducted to explore the mechanisms involved in collagen accumulation. A series of in vitro and in vivo experiments were designed to assess the role of the collagen regulators prolyl 4-hydroxylase subunit alpha 1 (P4HA1) and yes-associated protein (YAP) in sensitizing GBM cells to TMZ. RESULTS: This study revealed that TMZ exposure significantly elevated collagen type I (COL I) expression in both GBM patients and murine models. Collagen accumulation sustained GBM cell survival under TMZ-induced stress, contributing to enhanced TMZ resistance. Mechanistically, P4HA1 directly binded to and hydroxylated YAP, preventing ubiquitination-mediated YAP degradation. Stabilized YAP robustly drove collagen type I alpha 1 ( COL1A1) transcription, leading to increased collagen deposition. Disruption of the P4HA1-YAP axis effectively reduced COL I deposition, sensitized GBM cells to TMZ, and significantly improved mouse survival. CONCLUSION P4HA1 maintained YAP-mediated COL1A1 transcription, leading to collagen accumulation and promoting chemoresistance in GBM.
Temozolomide ; Humans ; Glioblastoma/drug therapy* ; Animals ; Mice ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; YAP-Signaling Proteins ; Hydroxylation ; Dacarbazine/pharmacology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Transcription Factors/metabolism* ; Collagen/biosynthesis* ; Collagen Type I/metabolism* ; Prolyl Hydroxylases/metabolism* ; Antineoplastic Agents, Alkylating/therapeutic use*

Objective To investigate the key factors influencing the implementation of long-acting injection-promoting policies and propose effective improving paths.Methods Qualitative interviews were carried out for stakeholders involved in the promotion of long-acting injections,based on the consolidated framework for implementation research.Additionally,countermeasures for identified barriers were proposed based on expert recommendations for implementation changes.Results A total of 46 health administrators,healthcare workers,and patients in Beijing were interviewed.The study identified several barriers in the strength and quality of evidence,adaptability,relative advantage,complexity and cost,patient needs and resources,external collaboration,external policies and incentives,organizational structural characteristics,and self-efficacy.Conclusions From the perspectives and experiences of stakeholders,the promotion of long-acting injections has shown initial success but still faces multiple obstacles.It is recommended that efforts should be made to coordinate and adapt policies,improve and incentivize relative organizations,and continuously strengthen the advocacy and education for individuals.
Humans ; Beijing ; Delayed-Action Preparations ; Health Personnel ; Health Policy ; Injections

Objective To evaluate the prognosis and safety of patients with advanced pancreatic ductal adenocarcinoma(PDAC)who received I-125 seed implantation in treatment with anti-PD-1 monoclonal antibody+chemotherapy.Methods A retrospective analysis was conducted on patients with stage Ⅳ metastatic PDAC who received anti-PD-1 combined chemotherapy treatment at Yixing Hospital,Jiangsu University from Jan 2021 to Jun 2023.Patients were divided into two groups based on whether they received I-125 seed implantation:the I-125 seed implantation+anti-PD-1 monoclonal antibody+Chemotherapy group(IPC group)and the anti-PD-1 monoclonal antibody+chemotherapy group(PC group).The follow-up period ranged from 2 to 24 months,with a median follow-up time of 9 months.The prognosis of patients was analysed in combination with peripheral blood biomarkers.The peripheral lymphocyte subsets of patients in different treatment groups were preliminarily analysed by flow cytometry.Results A total of 13 patients were included,with 5 in the IPC group and 8 in the PC group.Progression-free survival(PFS)and overall survival(OS)in the IPC group were significantly longer than those in the PC group.The treatment in the IPC group was relatively safe,adverse reactions were controllable.The neutrophil-lymphocyte ratio(NLR)and CD4/CD8 ratio indicated that the prognosis of the IPC patients was better.The levels of regulatory T cells(Treg)and active regulatory T cells(aTreg)cells in the IPC patients were reduced after treatment compared with those of the PC patients.Conclusion The addition of I-125 seed implantation can improve the prognosis of patients with advanced PDAC who receive anti-PD-1 monoclonal antibody+chemotherapy,the post-treatment levels of patients'circulating aTreg cells are reduced,and the combination therapy has good safety.

Objective:To investigate the efficacy and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the treatment of BCR::ABL-negative chronic neutrophilic leukemia (CNL) and MDS/MPN with neutrophilia.Methods:This study retrospectively analyzed 12 cases of CNL and MDS/MPN with neutrophilia that underwent allo-HSCT from March 2017 to June 2024, comprising 7 males and 5 females with a median age of 48 ( IQR: 28, 59) years. The 2-year overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR), and transplantation-related mortality (TRM) rates were analyzed. Complications were also assessed. Results:Of the 12 patients, 6 received matched sibling HSCT and 6 received haploidentical HSCT. All patients had successful engraftment, and the median times of neutrophil and platelet engraftment were 17 ( IQR: 11, 24) days and 15 ( IQR: 9, 28) days, respectively. Grade Ⅱ–Ⅳ acute graft versus host disease (GVHD) and chronic GVHD occurred in 2 and 4 cases, respectively. The 2-year OS, DFS, CIR, and TRM rates were (65.6 ± 16.4) %, (41.7 ± 16.6) %, (47.2 ±18.2) %, and (11.1 ± 11.4) %, respectively, after a median follow-up time of 637 ( IQR: 330, 943) days. One patient died from treatment-related complications due to respiratory failure caused by coronavirus disease 2019. Two patients died due to relapse. Conclusion:Allo-HSCT can be applied as a safe and effective approach to treat CNL and MDS/MPN with neutrophilia.

Objective:To evaluate the safety and efficacy of donor-purified CD34 + stem cell boosts in patients with poor hematopoietic reconstruction (PHR) after haploid hematopoietic stem cell transplantation (haplo-HSCT) for aplastic anemia (AA) . Method:A retrospective analysis was conducted on 11 patients with AA and PHR who underwent haplo-HSCT and received donor-purified CD34 + stem cell boosts at Peking University People’s Hospital. Recovery of blood cell counts, incidence of graft-versus-host disease (GVHD), and overall survival (OS) were assessed. Results:Of the 11 patients with PHR, two were diagnosed with prolonged isolated thrombocytopenia (PT), one was primary poor graft function (PGF), and eight were diagnosed with secondary PGF. The median time to PHR diagnosis was 110 days (range: 60-330 days), and the median interval from transplantation to purified CD34 + hematopoietic stem cell infusion was 194 days (range: 125-456 days). The two patients with PT achieved complete platelet recovery at 22 and 13 days after CD34 + stem cell infusion, respectively. Among the remaining nine patients with PGF, six achieved complete hematopoietic recovery, with a median absolute neutrophil count recovery time of 19 days (8-158 days), HGB recovery time of 32.5 days (range: 13-158 days), and platelet recovery time of 31.5 days (range: 7-171 days). The incidence of chronic GVHD after infusion was 18.2%, with no cases of acute GVHD observed. The OS rate was 90.9% (10/11) in the 11 patients, with a median follow-up of 614 days (range: 153-1 765 days) . Conclusion:Donor-purified CD34 + stem cell boost may be an effective therapeutic strategy for PHR in patients with AA after haplo-HSCT.

Aim To investigate the effects of Mdivi-1 on A1 astrocyte activation and its associated signaling molecules.Methods CTX-TNA2 astrocytes were di-vided into the control,ACM,and low-,medium-,and high-dose Mdivi-1 groups based on concentration screening via CCK-8 assay.ACM,a DMEM high-glu-cose medium containing preset concentrations of IL-1α,TNF-α,and C1q,was used to induce A1 activa-tion.The ACM group was stimulated with ACM for 24 hours.Mdivi-1 groups were pretreated with correspond-ing concentrations of Mdivi-1 for 2 hours,followed by ACM stimulation for 24 hours.Real-time quantitative PCR and Western blot were employed to assess mRNA levels and protein expression of IL-1β,C3,and iNOS in all groups.Immunofluorescence and Western blot were used to detect the expression of signaling molecules NLRP3,caspase-1,and ASC.DHE labeling was used to assess and flow cytometry was used to examine reac-tive oxygen species(ROS)levels.Results The CCK-8 assay identified 5,10,and 25 μmol·L-1as ap-propriate concentrations for Mdivi-1 intervention in CTX-TNA2 cells.Real-time quantitative PCR and Western blot results indicated that,compared to the control group,IL-1 β,C3,and iNOS mRNA levels and protein expression were significantly elevated in the ACM group(P＜0.05).In contrast,these levels were significantly reduced in the 10 and 25 μmnol·L-1 Mdi-vi-1 groups compared to the ACM group(P＜0.05).Immunofluorescence and Western blot results confirmed that ACM stimulation significantly activated the NLRP3 inflammasome in astrocytes,while Mdivi-1 intervention effectively reversed the ACM-induced upregulation of NLRP3,caspase-1,and ASC.DHE staining results demonstrated that 5,10,and 25 μmol·L-1Mdivi-1 in-terventions partially reversed the ACM-induced in-crease in ROS levels in a dose-dependent manner.Conclusion Mdivi-1 effectively inhibits A1 astrocyte activation,potentially through modulation of ROS and the NLRP3 inflammasomes.

Inflammatory diseases (IDs) are a general term of diseases characterized by chronic inflammation as the primary pathogenetic mechanism, which seriously affect the quality of patient′s life and cause significant social and medical burden. Current drugs for IDs include nonsteroidal anti-inflammatory drugs, corticosteroids, immunomodulators, biologics, and antioxidants, but these drugs may cause gastrointestinal side effects, induce or worsen infections, and cause non-response or intolerance. Given the outstanding performance of metal polyphenol network (MPN) in the fields of drug delivery, biomedical imaging, and catalytic therapy, its application in the diagnosis and treatment of IDs has attracted much attention and significant progress has been made. In this paper, we first provide an overview of the types of IDs and their generating mechanisms, then sort out and summarize the different forms of MPN in recent years, and finally discuss in detail the characteristics of MPN and their latest research progress in the diagnosis and treatment of IDs. This research may provide useful references for scientific research and clinical practice in the related fields.

Ureaplasma urealyticum (UU) is one of the most commonly occurring pathogens associated with genital tract infections in infertile males, but the impact of seminal UU infection in semen on intrauterine insemination (IUI) outcomes is poorly understood. We collected data from 245 infertile couples who underwent IUI at The First Affiliated Hospital of USTC (Hefei, China) between January 2021 and January 2023. The subjects were classified into two groups according to their UU infection status: the UU-positive group and the UU-negative group. We compared semen parameters, pregnancy outcomes, and neonatal birth outcomes to investigate the impact of UU infection on IUI outcomes. There were no significantly statistical differences in various semen parameters, including semen volume, sperm concentration, total and progressive motility, sperm morphology, leukocyte count, the presence of anti-sperm antibody, and sperm DNA fragmentation index (DFI), between the UU-positive and UU-negative groups of male infertile patients (all P > 0.05). However, the high DNA stainability (HDS) status of sperm differed between the UU-positive and UU-negative groups, suggesting that seminal UU infection may affect sperm nuclear maturation ( P = 0.04). Additionally, there were no significant differences in pregnancy or neonatal birth outcomes between the two groups (all P > 0.05). These results suggest that IUI remains a viable and cost-effective option for infertile couples with UU infection who are facing infertility issues.
Humans ; Male ; Ureaplasma Infections/complications* ; Female ; Infertility, Male/therapy* ; Ureaplasma urealyticum/isolation & purification* ; Pregnancy ; Adult ; Pregnancy Outcome ; Semen Analysis ; Insemination, Artificial ; Semen/microbiology* ; China

OBJECTIVES: To investigate the genomic characteristics and prognostic factors of juvenile myelomonocytic leukemia (JMML) with RAS mutations. METHODS: A retrospective analysis was conducted on the clinical data of JMML children with RAS mutations treated at the Hematology Hospital of Chinese Academy of Medical Sciences, from January 2008 to November 2022. RESULTS: A total of 34 children were included, with 17 cases (50%) having isolated NRAS mutations, 9 cases (27%) having isolated KRAS mutations, and 8 cases (24%) having compound mutations. Compared to children with isolated NRAS mutations, those with NRAS compound mutations showed statistically significant differences in age at onset, platelet count, and fetal hemoglobin proportion (P<0.05). Cox proportional hazards regression model analysis revealed that hematopoietic stem cell transplantation (HSCT) and hepatomegaly (≥2 cm below the costal margin) were factors affecting the survival rate of JMML children with RAS mutations (P<0.05); hepatomegaly was a factor affecting survival in the non-HSCT group (P<0.05). CONCLUSIONS Children with NRAS compound mutations have a later onset age compared to those with isolated NRAS mutations. At initial diagnosis, children with NRAS compound mutations have poorer peripheral platelet and fetal hemoglobin levels than those with isolated NRAS mutations. Liver size at initial diagnosis is related to the prognosis of JMML children with RAS mutations. HSCT can improve the prognosis of JMML children with RAS mutations.
Humans ; Leukemia, Myelomonocytic, Juvenile/therapy* ; Mutation ; Male ; Female ; Child, Preschool ; Retrospective Studies ; Child ; Infant ; GTP Phosphohydrolases/genetics* ; Membrane Proteins/genetics* ; Adolescent ; Hematopoietic Stem Cell Transplantation ; Proportional Hazards Models ; Proto-Oncogene Proteins p21(ras)/genetics* ; Prognosis