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.Application of Global Leadership Initiative on Malnutrition criteria in patients with liver cirrhosis
Minjie JIANG ; Juan CHEN ; Muchen WU ; Jing WU ; Xiaotong XU ; Juan LI ; Can LIU ; Yaping ZHAO ; Xin HUA ; Qinghua MENG
Chinese Medical Journal 2024;137(1):97-104
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.
3.Incidence of postoperative complications in Chinese patients with gastric or colorectal cancer based on a national, multicenter, prospective, cohort study
Shuqin ZHANG ; Zhouqiao WU ; Bowen HUO ; Huining XU ; Kang ZHAO ; Changqing JING ; Fenglin LIU ; Jiang YU ; Zhengrong LI ; Jian ZHANG ; Lu ZANG ; Hankun HAO ; Chaohui ZHENG ; Yong LI ; Lin FAN ; Hua HUANG ; Pin LIANG ; Bin WU ; Jiaming ZHU ; Zhaojian NIU ; Linghua ZHU ; Wu SONG ; Jun YOU ; Su YAN ; Ziyu LI
Chinese Journal of Gastrointestinal Surgery 2024;27(3):247-260
Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.
6.Comparison of two surgical methods for the treatment of intertrochanteric fractures of the femur in elderly patients with knee osteoarthritis
Qian WAN ; Chun-Hu WU ; Hua-Dong YIN ; Xiao-Feng ZHU ; Yu LIU ; You-Liang YU
China Journal of Orthopaedics and Traumatology 2024;37(10):985-990
Objective To explore the difference in the effectiveness between proximal femoral nail anti-rotation(PFNA)and proximal femoral locking compression plate(PFLCP)of intertrochanteric fracture in the elderly patients combined with knee osteoarthritis.Methods The clinical data of 65 intertrochanteric femoral fractures combined with knee osteoarthritis be-tween June 2015 and February 2021 were retrospectively analyze.They were divided into two groups according to the different surgical methods.PFNA group was composed of 36 patients,12 males and 24 females,aged from 61to 88 years old with an av-erage of(77.0±6.4)years old.There were 17 cases of left injury and 19 cases of right injury.According to modified Evans clas-sification,there were 3 cases of type Ⅱ,19 cases of type Ⅲ,10 cases of type Ⅳ,and 4 cases of type Ⅴ.PFLCP group was com-posed of 29 patients,11 males and 18 females,aged from 60 to 92 years old with an average of(78.8±6.5)years old.There were 14 cases of left injury and 15 cases of right injury.According to modified Evans classification,there were 2 cases of typeⅡ,18 cases of type Ⅲ,7 cases of type Ⅳ,and 2 cases of type Ⅴ.Comparison of operation time,intraoperation blood loss,postoperative bed time,incidence of postoperative complications,Harris score at 6 months and 1 year postoperation.Results All 65 patients were followed up ranging from 12 to 24 months with an average of(16.9±3.6)months.In the PFNA and PFLCP groups,the operation time was respectively(57.6±6.8)min and(77.4±6.5)min,the intraoperative blood loss was(128.3±50.3)ml and(156.3±23.9)ml,postoperative bed time was(4.0±2.5)days and(8.1±2.0)days,Harris score at 6 months post-operative was(45.3±8.6)points and(36.3±7.0)points.There were significant differences between two groups(P<0.05).Inci-dence of postoperative complications was 19.4%(7/36)and 34.5%(10/29),Harris score at 1 year postoperative was(60.8±6.7)points and(59.0±8.1)points.There was no significant difference between the two groups(P>0.05).Conclusion Compared with PFLCP,PFNA treatment of elderly patients with knee osteoarthritis between the femoral intertrochanteric fractures shorter surgical time,less intraoperative blood loss,bed rest after surgery,short-term hip function recovery better,when the affected knee joint can tolerate traction,can be used as a priority.
7.Incidence of postoperative complications in Chinese patients with gastric or colorectal cancer based on a national, multicenter, prospective, cohort study
Shuqin ZHANG ; Zhouqiao WU ; Bowen HUO ; Huining XU ; Kang ZHAO ; Changqing JING ; Fenglin LIU ; Jiang YU ; Zhengrong LI ; Jian ZHANG ; Lu ZANG ; Hankun HAO ; Chaohui ZHENG ; Yong LI ; Lin FAN ; Hua HUANG ; Pin LIANG ; Bin WU ; Jiaming ZHU ; Zhaojian NIU ; Linghua ZHU ; Wu SONG ; Jun YOU ; Su YAN ; Ziyu LI
Chinese Journal of Gastrointestinal Surgery 2024;27(3):247-260
Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.
8.Analysis of the efficacy of subretinal injection and intravitreal injection of conbercept in the treatment of polypoidal choroidal vasculopathy
Teng LIU ; Xiao YU ; Xiaojian WU ; Yuling ZOU ; Kangcheng LIU ; Hua ZOU ; Wei WU ; Chenghao XU ; Zhipeng YOU
Chinese Journal of Ocular Fundus Diseases 2024;40(6):421-428
Objective:To observe the clinical effect of subretinal injection and intravitreal injection of conbercept in the treatment of polypoid choroidal vasculopathy (PCV).Methods:A prospective, randomized double-blind controlled study. From June 2022 to January 2023, 35 patients of 35 eyes with PCV diagnosed at Affiliated Eye Hospital of Nanchang University were included in the study. All patients were first-time recipients of treatment. Best corrected visual acuity (BCVA), optical coherence tomography (OCT), and indocyanine green angiography (ICGA) were performed in all affected eyes. BCVA was performed using an international standard visual acuity chart and converted to logarithmic minimum resolved angle (logMAR) visual acuity for statistical purposes. Enhanced depth imaging with OCT instrument was used to measure the macular retinal thickness (MRT), subfoveal choroidal thickness (SFCT), and pigment epithelium detachment (PED) height. Randomized numerical table method was used to divide the patients into subretinal injection group (group A) and vitreous cavity injection group (Group B), 18 cases with 18 eyes and 17 cases with 17 eyes, respectively. Comparison of age ( t=0.090), disease duration ( t=-0.370), logMAR BCVA ( t=?0.190), MRT ( t=0.860), SFCT ( t=0.247), and PED height ( t=?0.520) between the two groups showed no statistically significant difference ( P>0.05). The eyes of group A were given one subretinal injection of 10 mg/ml conbercept 0.05 ml (containing conbercept 0.5 mg), and subsequently administered on demand (PRN); eyes in group B were given intravitreal injection of 10 mg/ml conbercept 0.05 ml (containing conbercept 0.5 mg). The treatment regimen was 3+PRN. Lesions were categorized into active and quiescent according to the results of post-treatment OCT and BCVA. Active lesions were treated with intravitreal injection of conbercept at the same dose as before; stationary lesions were followed up for observation. BCVA and OCT were performed at 1, 2, 3, 6 and 9 months after treatment; ICGA was performed at 3, 6 and 9 months. BCVA, MRT, SFCT, and PED height changes before and after treatment were compared and observed in the affected eyes of the two groups. Independent sample t-test was used to compare between the two groups. Results:With the prolongation of time after treatment, the BCVA of the affected eyes in groups A and B gradually increased, and the MRT, SFCT, and PED height gradually decreased. Compared with group B, at 2, 3, 6, and 9 months after treatment, the BCVA of group A was significantly improved, and the difference was statistically significant ( t=?2.215, ?2.820, ?2.559, ?4.051; P<0.05); at 1, 2, 3, 6, and 9 months after treatment, the MRT of the affected eyes in group A ( t=?2.439, ?3.091, ?3.099, ?3.665, ?5.494), SFCT ( t=?3.370, ?3.058, ?3.268, ?4.220, ?4.121), and PED height ( t=?3.460, ?4.678, ?4.956, ?5.368, ?6.396) were significantly reduced, and the differences were statistically significant ( P<0.05). No complications such as intraocular inflammation, high intraocular pressure, or vitreous hemorrhage occurred in any of the affected eyes during or after treatment. Conclusion:Compared with the intravitreal injection of conbercept, the subretinal injection of conbercept can more effectively reduce the height of MRT, SFCT, PED height, and improve the visual acuity of the affected eyes with PCV.
9.Construction of training indexes of post competency of dental hygienist
You WU ; Dongling LIU ; Wenjuan CHANG ; Hua YANG
Chinese Journal of Practical Nursing 2023;39(14):1059-1065
Objective:To construct training indexes of post competency of dental hygienist, and to provide objective basis for the establishment of the index system of the transition from dental nurse to dental hygienist in the future.Methods:The relevant literature of post competency of dental hygienist was searched from the databases such as PubMed, Medline, Web of Science, China National Knowledge Internet, Wanfang database. The search time was from the establishment of the database to March 2021. The expert letter inquiry questionnaire was designed through preliminary consultation.Delphi expert consultation was conducted for 20 dental experts from Beijing city, Chongqing city, Jiangsu province, Sichuan province, Jilin province from May to November 2021, and model indexes and weight assignment of post competency of dental hygienist were determined.Results:Three rounds of Delphi expert consultation were conducted, the effective recoveries of the questionnaires were 100%, the expert authority coefficients were 0.81, 0.81, 0.83, respectively, the coefficient of variation of expert consultation was 0.000-0.386, 0.000-0.300 and 0.000-0.250, respectively, the coordination degree of expert opinions in the third round of consultation was 0.679, 0.428 and 0.389 (all P<0.01). The formed training indexes of post competency of dental hygienist included 4 first-level indexes, 20 second-level indexes and 60 third-level indexes. Conclusions:The training index system of post competency of dental hygienist in this study is scientific, reliable, and practical, to provide reference for training and assessment of post competency of dental hygienist and objective basis for establishing the indexes system of dental nurse to dental hygienist in the future.
10.Research progress on the protective effect and mechanism of puerarin on diabetic retinopathy
Hua ZOU ; Zhi-Peng YOU ; Xiao-Jian WU
International Eye Science 2023;23(8):1295-1298
Increasing prevalence and incidence of diabetes mellitus(DM)-the most common chronic consumptive disease worldwide-has a devastating impact on people's daily lives, particularly through the deterioration or complete loss of vision brought on by diabetic retinopathy(DR). Therefore, it is imperative to investigate the pathogenesis and effective treatment of DR. Meanwhile, Pueraria lobata is the extensively used dried root of kudzu or dried kudzu, also known as Pueraria flavonoids. Moreover, its roots are primarily composed of isoflavones, Pueroside ABC, triterpenes, and alkaloids, which can calm cardio-cerebrovascular smooth muscle and enhance microcirculation. Currently, it is widely employed for the treatment of cardio-cerebrovascular diseases, osteonecrosis, DM and its complications, neurodegenerative disorders, endometriosis and tumor diseases. Inhibiting retinal neovascularization, alleviating ischemia and hypoxia, decreasing advanced glycation end products in diabetes, raising insulin-like growth factor(IGF)expression while decreasing tumor necrosis factor-α(TNF-a)expression, decreasing vascular endothelial growth factor(VEGF)expression, reducing retinal nerve cell death, inhibiting the NOD-like receptor protein 3(NLRP3)inflammatory pathway and inhibiting ferroptosis are all mechanisms by which puerarin(Pue)has been found to protect the retina in recent studies. Thus, this article summarizes the current comprehension of the mechanism and protective effect of Pue on diabetic retina, serving as a guidepost for its future development and application.

Result Analysis
Print
Save
E-mail