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.

Nonobstructive azoospermia (NOA), one of the most severe types of male infertility, etiology often remains unclear in most cases. Therefore, this study aimed to detect four biallelic detrimental variants (0.5%) in the minichromosome maintenance domain containing 2 ( MCMDC2 ) genes in 768 NOA patients by whole-exome sequencing (WES). Hematoxylin and eosin (H&E) demonstrated that MCMDC2 deleterious variants caused meiotic arrest in three patients (c.1360G>T, c.1956G>T, and c.685C>T) and hypospermatogenesis in one patient (c.94G>T), as further confirmed through immunofluorescence (IF) staining. The single-cell RNA sequencing data indicated that MCMDC2 was substantially expressed during spermatogenesis. The variants were confirmed as deleterious and responsible for patient infertility through bioinformatics and in vitro experimental analyses. The results revealed four MCMDC2 variants related to NOA, which contributes to the current perception of the function of MCMDC2 in male fertility and presents new perspectives on the genetic etiology of NOA.
Humans ; Male ; Azoospermia/genetics* ; Meiosis/genetics* ; Spermatogenesis/genetics* ; Adult ; Exome Sequencing ; Microtubule-Associated Proteins/genetics* ; Alleles ; Infertility, Male/genetics*

OBJECTIVE: To study the clinical effects of ibrutinib in the treatment of relapsed/refractory diffuse large B-cell lymphoma (RRDLBCL). METHODS: A total of 101 patients with RRDLBCL in Daqing People's Hospital from September 2019 to September 2022 were selected. 45 patients were received ibrutinib monotherapy, 36 patients were received a combination therapy of ibrutinib, rituximab, and lenalidomide, and 20 patients were received a combination therapy of ibrutinib and lenalidomide. The clinical effects were observed. RESULTS: The median duration of treatment for all patients was 4 (2-9) months. The disease control rates(DCR) and objective response rates(ORR) in the ibrutinib monotherapy group were 46.67% and 26.67%, respectively. In the combination therapy group of ibrutinib, rituximab, and lenalidomide, the DCR and ORR were 69.44% and 44.44%, respectively. In the combination therapy group of ibrutinib and lenalidomide, the DCR and ORR were 60.00% and 35.00%, respectively. The DCR and ORR in the combination therapy group of ibrutinib, rituximab, and lenalidomide were significantly higher than those in the ibrutinib monotherapy group (P < 0.05). There were no significant differences in DCR and ORR between the combination therapy group of ibrutinib and lenalidomide and the ibrutinib monotherapy group (P >0.05). The median follow-up time of all patients was 15 (5-35) months, with a median overall survival(OS) of 21.0 (15.8-26.2) months and a median progression-free survival(PFS) of 14.0 (12.1-15.9) months. In the ibrutinib monotherapy group, the median OS and PFS were 15.0 (12.1-17.9) months and 12.0 (11.0-13.0) months, respectively. In the combination therapy group of ibrutinib and lenalidomide, the median OS and PFS were 22.0 (13.3-30.7) months and 16.0 (14.1-19.7) months, respectively. In the combination therapy group of ibrutinib, rituximab, and lenalidomide, the median OS and PFS were 23.0 (19.7-26.3) months and 17.0 (14.8-19.1) months, respectively. The median OS and PFS in the combination therapy group of ibrutinib, rituximab, and lenalidomide were significantly higher than those in the ibrutinib monotherapy group (P < 0.05). There were no significant differences in median OS and PFS between the combination therapy group of ibrutinib and lenalidomide and the combination therapy group of ibrutinib, rituximab, and lenalidomide (P >0.05). Hematological adverse reactions included neutropenia in 14 cases (13.86%), thrombocytopenia in 16 cases (15.84%), and leukopenia in 13 cases (12.87%). Non-hematological adverse reactions mainly included nausea and vomiting in 33 cases (32.67%) and fatigue in 44 cases (43.56%). CONCLUSION Ibrutinib has certain clinical effects and good safety in the treatment of RRDLBCL.
Humans ; Piperidines/therapeutic use* ; Lymphoma, Large B-Cell, Diffuse/drug therapy* ; Adenine/therapeutic use* ; Rituximab/therapeutic use* ; Lenalidomide/therapeutic use* ; Male ; Female ; Middle Aged ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Adult ; Aged ; Pyrimidines/therapeutic use* ; Pyrazoles/therapeutic use* ; Treatment Outcome

Male reproductive disorders have emerged as a global issue. Infertility affects 8% to 12% of couples of childbearing age. The sperm concentration and total sperm count of men have shown a significant downward trend over the past four decades, with a decrease of more than 50%. Male reproductive disorders are related to multiple factors. Circular RNA (circRNA) is a type of non-coding RNA with covalently closed circular structures. It is involved in a variety of biological processes, including gene expression regulation, protein function regulation and epigenetic regulation. Studies have shown that there are differences in the expression of circRNA in the testicles and semen between infertile patients and healthy people, suggesting that circRNA is involved in the process of spermatogenesis, and its abnormal expression is associated with male infertility. This review takes the biological functions of circRNA as the starting point and summarizes the research progress of circRNA in male reproductive disorders. CircRNA has the potential to serve as a novel biomarker due to its conservative, special structure and tissue specificity, which provides a new strategy for the clinical diagnosis of male reproductive disorders.
Humans ; Male ; RNA, Circular ; Infertility, Male/genetics* ; RNA/genetics* ; Spermatogenesis

The importance of gait assessment in the rehabilitation of cancer patients is gradually being recognized. However, quantitative analysis of balance ability in cancer patients is still limited. A total of 102 cancer patients meeting the inclusion criteria were recruited from Hefei Cancer Hospital, Chinese Academy of Sciences. Their balance ability was evaluated using the Berg Balance Scale (BBS). Gait data were collected by an electronic walkway and an IMU sensor system, including spatial-temporal and kinematic gait features such as step length, cadence, support time, and range of motion. Recursive feature elimination was used for feature selection. Ridge, Elastic Net, SVR, RF, and AdaBoost models were used to predict balance ability scores. Five-fold cross-validation was used to evaluate the performance of these models. Results show that the SVR model achieves the best performance with fifteen features (RMSE=3.22, R ²=0.91), followed by Ridge (RMSE=3.63, R ²=0.89). A method for evaluating balance ability based on gait features is proposed, providing a quantitative tool for personalized rehabilitation interventions in cancer patients.
Humans ; Postural Balance ; Neoplasms/rehabilitation* ; Gait ; Gait Analysis ; Biomechanical Phenomena ; Female

OBJECTIVE: Recent studies have overturned the traditional concept of the lung as a "sterile organ" revealing that pulmonary microbiota dysbiosis and abnormal surfactant proteins (SPs) expression are involved in the progression of silicosis. This study aimed to investigate the relationship between abnormal SPs expression and dysbiosis of lung microbiota in silica-induced lung fibrosis, providing insights into mechanisms of silicosis. METHODS: Lung pathology, SPs expression, and microbiota composition were evaluated in silica-exposed mice. A mouse model of antibiotic-induced microbiota depletion was established, and alveolar structure and SPs expression were assessed. The roles of the lung microbiota and SPs in silicosis progression were further evaluated in mice with antibiotic-induced microbiota depletion, both with and without silica exposure. RESULTS: Silica exposure induced lung inflammation and fibrosis, along with increased expression of SP-A expression. Antibiotics (Abx)-induced microbiota depletion elevated SP-A and SP-D expression. Furthermore, silica exposure altered lung microbiota composition, enriching potentially pathogenic taxa. However, antibiotic-induced microbiota depletion prior to silica exposure reduced silica-mediated lung fibrosis and inflammation. CONCLUSION Lung microbiota is associated with silica-induced lung injury. Overproduction of SP-A and SP-D, induced by Abx-induced microbiota depletion, may enhance the resistance of mouse lung tissue to silica-induced injury.
Animals ; Silicosis/prevention & control* ; Lung/metabolism* ; Mice ; Anti-Bacterial Agents/pharmacology* ; Microbiota/drug effects* ; Silicon Dioxide/toxicity* ; Mice, Inbred C57BL ; Male ; Pulmonary Surfactant-Associated Proteins/genetics*

Objective:To investigate the effects of stimulator of interferon gene (STING) on ferroptosis mediated by acyl-CoA synthetase long-chain family member 4 (ACSL4) in mouse dendritic cells (DCs) under sepsis, providing a basis for improving the dysregulation of immune response in sepsis caused by factors such as wound infection.Methods:This study was an experimental research. The mouse DC line DC2.4 in the logarithmic growth phase (with passages 3-10) were divided into lipopolysaccharide (LPS) stimulation 0 h (unstimulated) group, LPS stimulation 6 h group, LPS stimulation 12 h group, LPS stimulation 18 h group, and LPS stimulation 24 h group according to the random number table (the same grouping method below), which were cultured with 1 μg/mL LPS (the same concentration below) for the corresponding time. The protein expressions of phosphorylated STING (p-STING), STING, and ACSL4 in cells were determined by Western blotting. DC2.4 successfully transfected with lentivirus containing STING gene small interfering RNA (hereinafter referred to as siSTING) were divided into siSTING+phosphate buffer solution (PBS) group and siSTING+LPS group. DC2.4 successfully transfected with empty lentivirus were divided into empty vector+PBS group and empty vector+LPS group. After being stimulated with PBS or LPS and cultured for 24 hours, the protein expressions of p-STING, STING, and ACSL4 in cells were determined as above. Cell lipid peroxidation degrees were observed using the lipid peroxidation assay kit, and cell apoptosis rates were detected using flow cytometry. The sample numbers in the above cell experiments were all 3. Eighty male C57BL/6J mice aged 6 to 8 weeks were divided into sham surgery+normal saline (NS) group, cecal ligation and puncture (CLP)+NS group, sham surgery+C-176 group, and CLP+C-176 group, with 20 mice in each group. Mice in the two C-176 groups were intraperitoneally injected with C-176, while mice in the two NS groups were intraperitoneally injected with an equivalent volume of NS. One hour later, sham surgery was performed on the mice in the two sham surgery groups, and CLP surgery was performed on the mice in the two CLP groups to establish a sepsis model. At 24 h post-surgery, 10 mice from each group were sacrificed to extract spleen DCs, and protein expression, lipid peroxidation, and apoptosis rates were detected as above ( n=3). Hematoxylin-eosin staining was performed to observe pathological damage in the heart, liver, lung, and kidney tissue. The remaining 10 mice in each group were observed for survival within 7 days after surgery. Results:The protein expressions of p-STING, STING, and ACSL4, as well as the p-STING/STING ratio in DC2.4 in LPS stimulation 24 h group were significantly higher than those in LPS stimulation 0 h group ( P<0.05). After 24 h of culture, the protein expressions of p-STING, STING, and ACSL4 in DC2.4 in siSTING+LPS group and empty vector+PBS group were significantly lower than those in empty vector+LPS group ( P<0.05); the lipid peroxidation degrees of DC2.4 in siSTING+LPS group and empty vector+PBS group were weaker than those in empty vector+LPS group. The apoptosis rates of DC2.4 in empty vector+PBS group, empty vector+LPS group, siSTING+PBS group, and siSTING+LPS group were (15.7±3.0)%, (37.8±2.9)%, (13.1±2.1)%, and (20.6±1.8)%, respectively. The apoptosis rates of DC2.4 in empty vector+PBS group and siSTING+LPS group were significantly lower than that in empty vector+LPS group ( P<0.05). At 24 h post-surgery, the protein expressions of p-STING and ACSL4, and the p-STING/STING ratio in spleen DCs of mice in CLP+NS group were significantly higher than those in sham surgery+NS group and CLP+C-176 group ( P<0.05); the protein expression of STING in spleen DCs of mice in CLP+NS group was significantly higher than that in sham surgery+NS group ( P<0.05); the lipid peroxidation degrees of spleen DCs of mice in CLP+C-176 group and sham surgery+NS group were weaker than that in CLP+NS group. The apoptosis rates of spleen DCs of mice in sham surgery+NS group and CLP+C-176 group were significantly lower than that in CLP+NS group ( P<0.05), and the apoptosis rate of spleen DCs of mice in CLP+C-176 group was significantly higher than that in sham surgery+C-176 group ( P<0.05). Pathological tissue damage in the heart, liver, lung, and kidney of mice in CLP+NS group was significantly worse than that in sham surgery+NS group, while such damage in the above organs of mice in CLP+C-176 group was significantly alleviated compared with that in CLP+NS group. The survival ratio of mice in CLP+NS group within 7 days after surgery was significantly lower than that in sham surgery+NS group ( χ2=8.30, P<0.05). Conclusions:Under sepsis, STING activation in mouse DCs is significant, which enhances ACSL4-mediated ferroptosis. Inhibiting STING activation can significantly reduce ACSL4-mediated ferroptosis level in mouse DCs under sepsis, thereby improving the survival rate of septic mice.

Objective To explore the correlation between the expression of long non-coding RNA(lncRNA)brain ischemia-related factor(BIRF)and focally amplified lncRNA on chromosome 1(lncRNA FAL1)in serum and the degree of white matter lesions(WML)in patients with cerebral small vessel disease(CSVD).Methods From June 2021 to June 2023,102 CSVD patients admitted to Affiliated Hospital of Chengde Medical University were collected,and these patients were grouped into WML group(n=72)and non WML group(n=30)based on WML diagnostic criteria.According to the Fazekas score,the WML group was further grouped into mild WML group(n=24),moderate WML group(n=36)and severe WML group(n=12).Real-time fluorescence quantitative polymerase chain reaction(qRT-PCR)was applied to detect the levels of lncRNA BIRF and lncRNA FAL1 in serum.Pearson correlation was applied to analyze the correlation between serum lncRNA BIRF and lncRNA FAL1 levels.Receiver operating characteristic(ROC)curve was applied to analyze the diagnostic value of serum lncRNA BIRF and lncRNA FAL1 levels for severe WML in CSVD patients.Results The age(70.50±5.86 years),history of hypertension(Yes/No,43/29),history of diabetes(Yes/No,45/27),IL-33(68.35±6.80 pg/ml),IL-18(97.78±9.65 ng/L),ubiquitin carboxyl terminal hydrolase L1(UCH-L1)(0.29±0.10 μg/L)and lncRNA BIRF level(2.45±0.30)of patients in the WML group were higher than those in the non WML group(67.10±5.76 years,11/19,9/21,62.48±6.13 pg/ml,92.56±9.37 ng/L,0.24±0.06 μg/L,1.02±0.11),while the expression of serum lncRNA FAL1(0.52±0.10)was lower than that in the non WML group(1.04±0.15),with significant differences(t=2.683,4.518,8.978,4.085,2.510,2.550,25.346,20.500,all P<0.05).The serum lncRNA BIRF levels of CSVD patients in the mild,moderate and severe WML groups(2.23±0.23,2.47±0.31,2.82±0.42)were increased sequentially,while the expression of serum lncRNA FAL1(0.60±0.15,0.51±0.09,0.40±0.04)was decreased sequentially,with significant differences(F=14.913,13.899,all P<0.05).Pearson correlation analysis,the serum levels of lncRNA BIRF and lncRNA FAL1 in patients with WML were negatively correlated(r=-0.603,P<0.001),serum lncRNA BIRF was positively correlated with Fazekas score in WML patients(r=0.483,P<0.001),but serum lncRNA FAL1 was negatively correlated with Fazekas score(r=-0.507,P<0.001).The AUCs of serum lncRNA BIRF and lncRNA FAL1 levels alone and both combination for predicting severe WML in CSVD patients were 0.756(0.641～0.850),0.839(0.733～0.915)and 0.892(0.796～0.953),respectively,and the combination of the two was superior to the detection of serum lncRNA BIRF alone(Z=2.111,P=0.035).Conclusion The serum lncRNA BIRF level is increased and lncRNA FAL1 is reduced in patients with CSVD and WML,and both are related to the degree of WML in CSVD patients.

Human physiological indicators have become an important standard for assessing health in modern society.Traditional detection methods often require a separate laboratory,complex operation process and long detection time,so it is urgent to develop portable,fast and accurate on-site detection technologies for bioanalysis.Point-of-care testing(POCT),which differs from traditional laboratory testing,can realize the rapid in situ detection of biomarkers without the complicated analytical process of the laboratory.Smartphones,which are an essential tool in our daily life,not only have independent operating systems and built-in storage functions,but also have high-definition cameras,which have great application potential in POCT visualization.The combination of various biosensing technologies and smartphones has developed into a new direction in the field of POCT.This review mainly introduced the research progress of smartphone-based visual biosensors in POCT in recent years,including colorimetric sensors,fluorescence sensors,chemiluminescence sensors and electrochemiluminescence sensors.Finally,the problems faced by smart-phone-based visual biosensors in the application of POCT were summarized,and their future development was prospected.

Objective:To investigate the effect of stress-induced protein Sestrin2 (SESN2) on necroptosis of mouse dendritic cell (DC) induced by lipopolysaccharide (LPS) combined with zVAD, a panaspartate-specific cysteine protease (caspase) inhibitor.Methods:The DC2.4 cell line derived from the bone marrow of mouse in the 3rd to 10th generations was cultured. The cells were stimulated with LPS for 0 hour, 6 hours, 12 hours, and 24 hours, and grouped according to the stimulation time points. Western blotting was performed to determine the protein expression of SESN2 in each group. Overexpression empty lentivirus (NC), SESN2 gene overexpression RNA sequence lentivirus (SESN2 LV-RNA), small interfering empty lentivirus (NS), and SESN2 gene small interfering RNA sequence lentivirus (SESN2 siRNA) were transfected into DC2.4 cells. After 72 hours of transfection, cell fluorescence expression was observed under the inverted fluorescence microscope. Cells in each transfection group were stimulated with LPS for 24 hours. The blank control groups were set up and cultured with phosphate buffered saline (PBS) for 24 hours. Western blotting was performed to measure SESN2 protein expression. In the same groups as above, cells were stimulated with LPS+zVAD for 24 hours. The blank control groups were set up and cultured with PBS for 24 hours. Western blotting was used to determine the expression of mixed lineage kinase domain-like protein (MLKL) and phosphorylated-MLKL (p-MLKL). The p-MLKL levels and the number of positive cells were observed using laser scanning confocal microscopy. The necroptotic cell ratios were assessed by both flow cytometry and Hoechst staining.Results:Compared to the LPS 0 hour group, the expression of SESN2 in the LPS 24 hours group showed a significant increase. Therefore, 24 hours was chosen as the subsequent stimulation time point. After successful lentivirus transduction and 24 hours of cultivation, the MLKL phosphorylation level in the SESN2 siRNA+LPS+zVAD group was significantly higher than that in the NS+LPS+zVAD group. The MLKL phosphorylation in the SESN2 LV-RNA+LPS+zVAD group was significantly lower than that in the NC+LPS+zVAD group. The MLKL phosphorylation levels in both the NS+LPS+zVAD group and the NC+LPS+zVAD group were obviously higher than those in the NS+PBS group and the NC+PBS group, respectively. Laser scanning confocal microscopy showed that the trends in quantity and fluorescence intensity of p-MLKL protein expressions were consistent with the above results. The results from flow cytometry analysis and Hoechst staining showed that the rates of cell necrotic apoptosis in SESN2 siRNA+LPS+zVAD group were significantly higher than those in NS+LPS+zVAD group [flow cytometry analysis: (30.800±1.153)% vs. (20.800±1.114)%, Hoechst staining: (75.267±0.451)% vs. (46.267±3.371)%, both P < 0.05], indicating that knocking down SESN2 further exacerbated the occurrence of necroptosis. The necrotic apoptosis rates in SESN2 LV-RNA+LPS+zVAD group were significantly lower than those in NC+LPS+zVAD group [flow cytometry analysis: (7.160±0.669)% vs. (19.240±2.322)%, Hoechst staining: (32.433±3.113)% vs. (48.567±4.128)%, both P < 0.05], indicating that overexpressing SESN2 reversed such response and markedly reduced the proportion of necroptotic cells compared to the corresponding empty vector group. Conclusion:SESN2 exhibits an inhibitory effect on necroptosis of DC in sepsis. Targeted SESN2 expression may regulate the process of DC-mediated immune response in sepsis.