1.Analysis of T7 RNA Polymerase: From Structure-function Relationship to dsRNA Challenge and Biotechnological Applications
Wei-Chen NING ; Yu HUA ; Hui-Ling YOU ; Qiu-Shi LI ; Yao WU ; Yun-Long LIU ; Zhen-Xin HU
Progress in Biochemistry and Biophysics 2025;52(9):2280-2294
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.
2.Mechanism on Banxia Xiexintang Inducing Ferroptosis in Gastric Cancer Cells Based on Nrf2/GPX4 Signaling Pathway
Ling LI ; Yaxing LI ; Xue WANG ; Xiao QIU ; Wei GUO ; Hailiang HUANG ; Xijian LIU ; Tao HAN
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(6):10-19
ObjectiveTo observe the effect of Banxia Xiexintang (BXT) on the proliferation of human gastric cancer HGC-27, MKN-45, and AGS cells and its mechanism. MethodCell counting kit-8 (CCK-8) was used to detect the effects of different concentrations of BXT-containing serum (5%, 10%, and 20%) on the proliferation of HGC-27, MKN-45, and AGS cells. A mitochondrial membrane potential probe (TMRE) was used to detect the expression of mitochondrial membrane potential in cells. A kit was used to detect iron ion (Fe2+) content, lipid peroxide (LPO), and superoxide dismutase (SOD) activity. Western blot was used to detect the protein expression levels of glycogen synthase3β (GSK3β), phosphorylated GSK3β (p-GSK3β), nuclear factor E2 related factor 2 (Nrf2), and glutathione peroxidase 4 (GPX4). The real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA expression of member 11 of the cystine/glutamic acid reverse transporter solute vector family 7 (SLC7A11), member 2 of the heavy chain solute vector family 3 (SLC3A2), transferrin receptor 3 (TFRC), and tumor protein (TP)53. ResultCCK-8 results showed that BXT and capecitabine could significantly reduce the survival rate of three kinds of gastric cancer cells after treatment with drug-containing serum for 24 h (P<0.01). After 48 h of intervention with drug-containing serum, the survival rate of three kinds of gastric cancer cells was significantly decreased in both the capecitabine group and the BXT group compared with the blank group. The BXT group was dose-dependent, with 20% BXT having the most significant effect (P<0.01). In terms of biochemical indicators of ferroptosis, compared with the blank group, BXT and capecitabine significantly decreased the expression of mitochondrial membrane potential (P<0.01) and SOD activity (P<0.01) and significantly increased the contents of LPO and Fe2+ (P<0.01), so as to improve the sensitivity of gastric cancer cells to ferroptosis. In terms of the Nrf2/GPX4 pathway, compared with the blank group, the BXT group could reduce the protein expressions of p-GSK3β, Nrf2, and GPX4 (P<0.01) in gastric cancer cells and increase mRNA expressions of SLC7A11 and SLC3A2 (P<0.05). It could also increase the protein expression of GSK3β (P<0.01) and mRNA expression of TP53 and TFRC (P<0.05, P<0.01) in gastric cancer cells. Inhibition of the Nrf2/GPX4 pathway induces ferroptosis in gastric cancer cells. Compared with the capecitabine group, the 20% BXT group showed a more obvious effect. ConclusionBanxia Xiexintang can induce ferroptosis in gastric cancer cells HGC-27, MKN-45, and AGS by inhibiting the Nrf2/GPX4 pathway.
3.Effects on different frequencies of whole body vibration on gross motor function and walking function in children with dyskinetic cerebral palsy
Qiu ZHANG ; Jihua YU ; Weiping LI ; Yunqi LING ; Jianxiong WANG ; Fangyuan XU
The Journal of Practical Medicine 2024;40(3):353-359
Objective To provide reference for the subsequent clinical application of WBV,based on the impacts of whole body vibration(WBV)with different frequencies on gross motor function and walking function in children with dyskinetic cerebral palsy.Methods 60 children aged 6~12 with dyskinetic cerebral palsy,who had been treated at the department of rehabilitation medicine in the Affiliated Southwest Medical University from October 2021 to November 2022,were selected.They were randomly divided into a control group(n = 20),(25±5)Hz group(n = 20),and(35±5)Hz group(n = 20).All the three groups received conventional rehabilitation,while the(25±5)Hz group received additional WBV with(25±5)Hz and the(35±5)Hz group received WBV with(35±5)Hz.They were treated for eight weeks.The scores on D and E domains of GMFM-88,TUGT,the score on Berg Balance Scale,and footprint analysis were used for assessment of the efficacy after treatment.Results As compared with the baselines,the scores were improved in the three groups after treatment(P<0.001).BBS(F = 12.502),TUGT(F = 8.211),scores on D and E domains of GMFM-88(F = 12.802 and 8.505),stride length(F = 12.279),1MWT distance(F = 12.619),and step width(F = 13.582)were better in the(35±5)Hz group than in the(25±5)Hz group and the control group(P<0.05 and P<0.01);and the efficacy was better in the(25±5)Hz group than in the control group,the difference was statistically significant(P<0.05 and P<0.01).Conclusion WBV can improve trunk control,lower limb gross motor function,and walking function in children with involuntary motor type cerebral palsy.(35±5)Hz is better than(25±5)Hz for the efficacy of WBV.
4.Evaluation and application of automated quality control of automatic pipeline in clinical biochemical and immunological detection
Li′an HOU ; Xuesong SHANG ; Chaochao MA ; Liangyu XIA ; Li LIU ; Ying ZHANG ; Yujun SU ; Xin LIU ; Ling QIU
Chinese Journal of Laboratory Medicine 2024;47(1):86-93
Objective:To assess the applicability of fully automatic pipeline automated testing for internal quality control (automated quality control).Methods:Stability, assay efficiency and implementation costs of 18 biochemical tests, 5 immunoturbidimetric tests and 11 chemical illuminescent tests in the Department of Laboratory Medicine of Peking Union Hospital from January 2019 to July 2022 were evaluated using automated quality control implementation methods. The detailed method is as follows: quality control materials for biochemical, immunoturbidimetric and chemiluminescent tests were stored in the refrigerator in the pipeline which was controlled by the intermediate software, and were automatically retrieved and tested as pre-set followed by documenting and storing. The quality control setup for the biochemical tests included refreshing quality control materials daily and weekly,both of which were paralleled for 3 months. The on-line storage stability of quality control materials in the pipeline was evaluated by comparing the coefficients of variation ( CV) of the quality control results between the two patterns. Effect of automated quality control application was evaluated using 6 indicators, including the results′ variation of automatically performed and manually performed quality controls, the out-of-controlled rate, the consumption of quality control materials, the change of staff workload, the impact on the testing time of the first sample, and the failure rate of automated quality control. Results:(1) Storage stability of quality control materials in the pipeline: under the pattern of weekly refresh of the biochemical quality control materials, except for total carbon dioxide (TCO 2) (the CVs of low and high level quality control were respectively 20.24% and 21.82%) and sodium (the CV of low level quality control was 1.51%) that were greater than the allowable variation set by the laboratory, the CVs of the rest tests meet the lab requirements on the allowable variations. (2) The results′ variation of quality control in automatically performed and manually performed control patterns: in the patterns of daily refresh of biochemical quality control materials and weekly refresh of immunoturbidimetric and chemiluminescent quality control materials, the CVs of both low and high levels of quality control were lower in the automatically performed control pattern than that in manually performed pattern for 8 chemiluminescent items of dehydroepiandrosterone sulfate, estradiol, follicle stimulating hormone, luteinizing hormone, serum ferritin, serum folic acid, vitamin B12 and testosterone, 3 immunologic items of complement 3, C reactive protein and immunoglobulin G, and 10 biochemical items of alkaline phosphatase, glucose, calcium, chloride, potassium, lactate dehydrogenase, sodium, urea, low density lipoprotein cholesterol, and adenosine deaminase. The out-of-control rates of biochemistry, immunoturbidimetric and chemiluminescence tests in both quality control patterns conformed with the clinical routine work requirements. (3) Comparison of quality control materials′ consumption: compared with manually performed quality control, weekly consumption of automatically performed chemiluminescent quality control materials decreased 37.5% (from 8 ml to 5 ml); weekly consumption of automatically performed immunoturbidimetric quality control materials decreased 33.3% (from 3 ml to 2 ml). (4)Comparison of staff workload and first sample testing time: compared with manually performed quality control, automatical quality control reduced manual work by about 156 steps per week, and the daily initial testing time was earlier by 15 min on average. The failure rate was 54.5% (37/64) during the early-stage application of the automated quality control which dropped to 10.2% (13/128) in the late-stage. Conclusion:The results of automated quality control detected in the pipeline system meet the quality indicators′ requirements of the laboratory, and the application of automated quality control can improve the quality control, save costs, reduce workload, and improve work efficiency.
5.Advances in therapeutic drug monitoring methods based on liquid chromatography-tandem mass spectrometry
Ziying LI ; Jie XIE ; Ziyu QU ; You JIANG ; Di ZHANG ; Songlin YU ; Xiaoli MA ; Ling QIU ; Xinhua DAI ; Xiang FANG ; Xiaoping YU
Chinese Journal of Laboratory Medicine 2024;47(3):332-340
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology has the characteristics of high specificity and high throughput, making it rapidly applied and developed in the field of clinical testing. Its application in the monitoring of therapeutic drugs can effectively improve the quantitative accuracy and sensitivity, and formulate a personalized and optimal dosing plan for patients. However, this technology still faces some challenges, and automation, quality control, and quantitative traceability will be the future development direction.
6.Study on the Knowledge-Attitude-Practice questionnaire for patients receiving oral anticoagulant therapy based on the Delphi method
Xiaomei LEI ; Na WANG ; Qiao LING ; Xinting ZHU ; Sha QIU ; Daiyi LI ; Yan QIAN
China Pharmacy 2024;35(10):1260-1265
OBJECTIVE To develop a questionnaire of the Knowledge-Attitude-Practice (KAP) for patients receiving oral anticoagulant therapy. METHODS Under the guidance of the theory of KAP, literature analysis and interview method were used to design the initial KAP questionnaire for patients treated with oral anticoagulants. Delphi method was adopted to consult the initial questionnaire and modify the questionnaire based on expert suggestions to form the final questionnaire. RESULTS Two rounds of consultation were conducted with 18 experts, and 18 questionnaires were sent out and recovered in each round, so the positive coefficient of experts was 100%. The expert authority coefficient was 0.94. The average importance scores for all dimensions, factors, and items of the questionnaire in both rounds were ≥4 points. The coefficient of variation was ≤0.25. The Kendall’s concordance coefficient for the overall questionnaire and the three dimensions of knowledge, attitude, and practice ranged from 0.09 to 0.34 (all P<0.05). Following the first round of expert consultation, four items were modified, two items were deleted, and five items were added; after the second round of expert consultation, ten items were modified. The final version of the questionnaire included three dimensions (knowledge, attitudes, and practice), 17 questionnaire factors, and 40 items. CONCLUSIONS The questionnaire has high reliability and scientific validity with relatively concentrated expert opinions. It is suitable for assessing the knowledge, attitudes, and practice status of patients receiving oral anticoagulant therapy.
7.Aphasia in Right Hemiparesis and Pain in Left Waist:A Deceiving Case in Vascular Ehlers-Danlos Syndrome
Yining FU ; Jingmin ZHOU ; Feng LI ; Shangzhi HUANG ; Yining WANG ; Xia HONG ; Ke LYU ; Yaping LIU ; Ling LENG ; Wenjie ZHENG ; Zhengqing QIU ; Yicheng ZHU ; Yuehong ZHENG ; Yuexin CHEN
JOURNAL OF RARE DISEASES 2024;3(2):224-231
The Ehlers-Danlos syndrome(EDS)is a rare inherent connective tissue disorder.The prev-alence of EDS in the population is estimated at one out of ten thousand to one out of a hundred thousand.The vascular EDS(vEDS)are rare among the subtypes but are the worst in prognosis.The article reports a case of vEDS admitted to the hospital.The patient was a young man complaining of a sudden onset of aphasia in right hemiparalysis and severe left abdominal pain for unknown reasons.The diagnosis was made after the genetic testing.The patient suffered from vEDS.Then,the multi-disciplinary team(MDT)made a treatment plan tailored to this young patient.The complexity in classification and delusive presentations of the EDS make the correct diagnosis very challenging.This article hopes to report this case and to share the experiences to the bet-ter understanding of this disease.
8.Cell softness reveals tumorigenic potential via ITGB8/AKT/glycolysis signaling in a mice model of orthotopic bladder cancer
Shi QIU ; Yaqi QIU ; Linghui DENG ; Ling NIE ; Liming GE ; Xiaonan ZHENG ; Di JIN ; Kun JIN ; Xianghong ZHOU ; Xingyang SU ; Boyu CAI ; Jiakun LI ; Xiang TU ; Lina GONG ; Liangren LIU ; Zhenhua LIU ; Yige BAO ; Jianzhong AI ; Tianhai LIN ; Lu YANG ; Qiang WEI
Chinese Medical Journal 2024;137(2):209-221
Background::Bladder cancer, characterized by a high potential of tumor recurrence, has high lifelong monitoring and treatment costs. To date, tumor cells with intrinsic softness have been identified to function as cancer stem cells in several cancer types. Nonetheless, the existence of soft tumor cells in bladder tumors remains elusive. Thus, our study aimed to develop a microbarrier microfluidic chip to efficiently isolate deformable tumor cells from distinct types of bladder cancer cells.Methods::The stiffness of bladder cancer cells was determined by atomic force microscopy (AFM). The modified microfluidic chip was utilized to separate soft cells, and the 3D Matrigel culture system was to maintain the softness of tumor cells. Expression patterns of integrin β8 (ITGB8), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) were determined by Western blotting. Double immunostaining was conducted to examine the interaction between F-actin and tripartite motif containing 59 (TRIM59). The stem-cell-like characteristics of soft cells were explored by colony formation assay and in vivo studies upon xenografted tumor models. Results::Using our newly designed microfluidic approach, we identified a small fraction of soft tumor cells in bladder cancer cells. More importantly, the existence of soft tumor cells was confirmed in clinical human bladder cancer specimens, in which the number of soft tumor cells was associated with tumor relapse. Furthermore, we demonstrated that the biomechanical stimuli arising from 3D Matrigel activated the F-actin/ITGB8/TRIM59/AKT/mTOR/glycolysis pathways to enhance the softness and tumorigenic capacity of tumor cells. Simultaneously, we detected a remarkable up-regulation in ITGB8, TRIM59, and phospho-AKT in clinical bladder recurrent tumors compared with their non-recurrent counterparts.Conclusions::The ITGB8/TRIM59/AKT/mTOR/glycolysis axis plays a crucial role in modulating tumor softness and stemness. Meanwhile, the soft tumor cells become more sensitive to chemotherapy after stiffening, that offers new insights for hampering tumor progression and recurrence.
9.Comparison of the antiplatelet effects between vicagrel and clopidogrel in patients with different cytochrome P450 2C19 genotypes
Yinan CAO ; Zizhao QI ; Ling REN ; Jing LI ; Miaohan QIU ; Kexin WANG ; Hongbin SUN ; Yanchun GONG ; Yi LI ; Yaling HAN
Chinese Journal of Cardiology 2024;52(5):493-499
Objective:To compare the antiplatelet effects of vicagrel and clopidogrel in patients with different cytochrome P450 (CYP) 2C19 genotypes.Methods:This is a post-hoc analysis of a phase Ⅱ clinical trial of vicagrel, which included patients with coronary heart disease who underwent percutaneous coronary intervention from August 2018 to June 2019 in 18 centers. Patients were categorized based on the presence of CYP 2C19 *2 or *3 loss-of-function (LOF) alleles into LOF carrier group ( n=111) and non-LOF carrier group ( n=90). Each group included patients received vicagrel 5 mg, 6 mg, 7.5 mg, or clopidogrel 75 mg for 28 days per study protocol. P2Y 12 reaction units (PRU) were measured using VerifyNow at baseline, 6 to 8 hours after loading dose, 7 to 10 days after randomization, and 28 days after randomization and the percentage inhibition of platelet aggregation (%IPA) was calculated. The primary endpoint was %IPA on day 28. Within the patients from the General Hospital of Northern Theater Command, 8 to 12 patients in each study arms were enrolled in a prespecified pharmacokinetic sub-study, measuring the time to reach maximum plasma concentration (T max), peak plasma concentration (C max), and area under the plasma concentration-time curve (AUC). Results:Among 201 patients, the age was (58.8±8.5) years, and 139 (69.2%) were male. In non-LOF carriers, there was no significant differences in PRU values and %IPA between the vicagrel 5 mg, 6 mg, 7 mg, and clopidogrel groups at all time points (all P>0.05). In LOF carriers, %IPA was significantly higher in the vicagrel-treated groups than in the clopidogrel group at 6-8 hours after loading dose (22.9 (14.2, 31.5)% vs. 19.8 (11.0, 28.6)% vs. 29.5 (20.9, 38.0)% vs. 12.9 (3.9, 21.9)%, P=0.038) and 7-10 days after randomization (22.4 (14.2, 30.5)% vs. 34.4 (26.1, 42.6)% vs. 39.8 (31.8, 47.9)% vs. 24.7 (16.3, 33.2)%, P=0.001), with a trend towards higher %IPA in the vicagrel-treated groups at day 28 (30.4 (21.3, 39.6)% vs. 36.5 (27.2, 45.7)% vs. 40.8 (31.8, 49.8)% vs. 30.7(21.2, 40.2)%, P=0.056). Pharmacokinetic results of 35 patients showed that the C max and AUC of the active metabolite M15-2 of vicagrel was similar to that of clopidogrel in non-LOF carriers, but AUC between vicagrel 5 mg, 6 mg, 7 mg and clopidogrel were significantly different in LOF carriers ((5.6±0.6) h·μg -1·L -1 vs. (6.8±2.7) h·μg -1·L -1 vs. (9.2±3.3) h·μg -1·L -1 vs. (4.2±1.9) h·μg -1·ml -1, P=0.020). Conclusion:Vicagrel and clopidogrel have similar antiplatelet effects in non-LOF carriers, but vicagrel exhibits superior antiplatelet effects in LOF carriers.
10.Treatment status of tyrosine kinase inhibitor for newly-diagnosed chronic myeloid leukemia: a domestic multi-centre retrospective real-world study
Xiaoshuai ZHANG ; Bingcheng LIU ; Xin DU ; Yanli ZHANG ; Na XU ; Xiaoli LIU ; Weiming LI ; Hai LIN ; Rong LIANG ; Chunyan CHEN ; Jian HUANG ; Yunfan YANG ; Huanling ZHU ; Ling PAN ; Xiaodong WANG ; Guohui LI ; Zhuogang LIU ; Yanqing ZHANG ; Zhenfang LIU ; Jianda HU ; Chunshui LIU ; Fei LI ; Wei YANG ; Li MENG ; Yanqiu HAN ; Li'e LIN ; Zhenyu ZHAO ; Chuanqing TU ; Caifeng ZHENG ; Yanliang BAI ; Zeping ZHOU ; Suning CHEN ; Huiying QIU ; Lijie YANG ; Xiuli SUN ; Hui SUN ; Li ZHOU ; Zelin LIU ; Danyu WANG ; Jianxin GUO ; Liping PANG ; Qingshu ZENG ; Xiaohui SUO ; Weihua ZHANG ; Yuanjun ZHENG ; Qian JIANG
Chinese Journal of Hematology 2024;45(3):215-224
Objective:To retrospectively analyze the treatment status of tyrosine kinase inhibitors (TKI) in newly diagnosed patients with chronic myeloid leukemia (CML) in China.Methods:Data of chronic phase (CP) and accelerated phase (AP) CML patients diagnosed from January 2006 to December 2022 from 77 centers, ≥18 years old, and receiving initial imatinib, nilotinib, dasatinib or flumatinib-therapy within 6 months after diagnosis in China with complete data were retrospectively interrogated. The choice of initial TKI, current TKI medications, treatment switch and reasons, treatment responses and outcomes as well as the variables associated with them were analyzed.Results:6 893 patients in CP ( n=6 453, 93.6%) or AP ( n=440, 6.4%) receiving initial imatinib ( n=4 906, 71.2%), nilotinib ( n=1 157, 16.8%), dasatinib ( n=298, 4.3%) or flumatinib ( n=532, 7.2%) -therapy. With the median follow-up of 43 ( IQR 22-75) months, 1 581 (22.9%) patients switched TKI due to resistance ( n=1 055, 15.3%), intolerance ( n=248, 3.6%), pursuit of better efficacy ( n=168, 2.4%), economic or other reasons ( n=110, 1.6%). The frequency of switching TKI in AP patients was significantly-higher than that in CP patients (44.1% vs 21.5%, P<0.001), and more AP patients switched TKI due to resistance than CP patients (75.3% vs 66.1%, P=0.011). Multi-variable analyses showed that male, lower HGB concentration and ELTS intermediate/high-risk cohort were associated with lower cytogenetic and molecular responses rate and poor outcomes in CP patients; higher WBC count and initial the second-generation TKI treatment, the higher response rates; Ph + ACA at diagnosis, poor PFS. However, Sokal intermediate/high-risk cohort was only significantly-associated with lower CCyR and MMR rates and the poor PFS. Lower HGB concentration and larger spleen size were significantly-associated with the lower cytogenetic and molecular response rates in AP patients; initial the second-generation TKI treatment, the higher treatment response rates; lower PLT count, higher blasts and Ph + ACA, poorer TFS; Ph + ACA, poorer OS. Conclusion:At present, the vast majority of newly-diagnosed CML-CP or AP patients could benefit from TKI treatment in the long term with the good treatment responses and survival outcomes.

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