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.

Objective:To investigate two cases of rare pathogenic genes,initiation codon mutations in HBA2 gene,combined with Southeast Asian deletion and their family members to understand the relationship of HBA2:c.2T＞C and HBA2:c.2delT mutations with clinical phenotype.Methods:The peripheral blood of family members was obtained for blood cell analysis and capillary electrophoresis hemoglobin analysis.Gap-PCR and reverse dot blotting(RDB)were used to detect common types of mutations in α-thalassaemia gene.Sanger sequencing was used to analyze HBA1 and HBA2 gene sequence.Results:Two proband genotypes were identified as--SEA/αα with HBA2:c.2T＞C and--SEA/αα with HBA2:c.2delT.HBA2:c.2T＞C/WT and HBA2:c.2delT/WT was detected in family members.They all presented with microcytic hypochromic anemia.Conclusion:When HBA2:c.2T＞C and HBA2:c.2delT are heterozygous that can lead to static α-thalassemia phenotype,and when combined with mild α-thalassemia,they can lead to the clinical manifestations of hemoglobin H disease.This study provides a basis for genetic counseling.

Objective:To analyze the effectiveness and interobserver agreement of the Parer five-tier, the National Institute of Child Health and Human Development (NICHD) three-tier, and the International Federation of Gynecology and Obstetrics (FIGO) three-tier electronic fetal monitoring (EFM) systems in identification of neonatal acidosis during labor.Methods:This retrospective study was conducted on full-term singleton cephalic deliveries with neonatal acidosis (umbilical artery blood gas pH≤7.1) and normal newborns (umbilical artery blood gas pH≥7.2) in the Nanjing Drum Tower Hospital, Nanjing University Medical School from January to December 2020. EFM tracings during the last 30-60 min before delivery were collected. Four obstetricians independently described the features of randomly sorted and coded EFM tracings. Another obstetrician categorized these tracings using the NICHD three-tier, FIGO three-tier, and Parer five-tier evaluation systems based on the features. All researchers were masked to the clinical characteristics and maternal and neonatal outcomes. The sensitivity and specificity for identifying neonatal acidosis, as well as the interobserver agreement, were analyzed for all three systems. Independent sample t-test, Chi-square (or Fisher's exact test) and Mann-Whitney U tests were used for statistical analysis. Inter-group comparisons of sensitivity and specificity between the three evaluation systems were assessed using McNemar's test. The Kappa statistic was used to analyze interobserver agreement. Results:This study included a total of 3 558 cases. After propensity score matching, there were 44 cases of neonatal acidosis and 78 control cases. There were no significant differences in parity, gestational weeks, modes of delivery, placental abruption, or analgesia rates between the two groups. The rates of instrumental vaginal delivery and neonatal intensive care unit (NICU) admission in the acidosis group were significantly higher than those in the control group [15.8% (7/44) vs. 2.6% (2/78), χ2=8.45, P=0.003; 31.8% (14/44) vs. 12.8% (10/78), χ2=8.45, P=0.004], while the umbilical artery blood pH and mean base excess were lower in the acidosis group than in the control group [7.04±0.07 vs. 7.30±0.05, t=4.98; (－12.40±3.32) vs. (－5.64±1.95) mmol/L, t=13.61; both P<0.001]. (2) Using the NICHD three-tier system, 95.5% (42/44) of the acidosis cases and 89.7% (70/78) of the control cases were classified as having category Ⅱ EFM tracings, indicating potential fetal acid-base imbalance; category Ⅲ EFM tracings were only observed in 4.5% (2/44) of the cases in the acidosis group. With the FIGO three-tier system, 81.8% (36/44) of the acidosis cases were categorized as having "pathological" tracings, and with the Parer five-tier system, 86.4% (38/44) of the acidosis cases were correctly classified into the "orange or red" risk zones that indicated acid-base imbalance. Among the control cases, there were 28.2% (22/78) with EFM tracings of "normal patterns" categorized by the FIGO three-tier system, and 41.0% (32/78) classified into the "green or blue" risk zones by the Parer five-tier system, which indicated good fetal conditions. None of the acidosis cases were misdiagnosed as being normal by the Parer five-tier system. (3) Compared with the NICHD three-tier system, both the FIGO three-tier and the Parer five-tier systems showed increased diagnostic sensitivity [4.5% (1.2%- 14.5%) vs. 81.8% (66.8%-89.4%) and 86.4% (71.8%-92.4%)], but decreased specificity [100.0% (95.3%- 100.0%) vs. 87.2% (78.0%-92.9%) and 84.6% (75.0%-91.0%)]. There was no statistically significant difference in the sensitivity or specificity between the FIGO three-tier and Parer five-tier systems for identifying neonatal acidosis ( P=0.727 and 0.791). (4) When reading the tracings of control cases, the total agreement rate for the NICHD three-tier system by different observers was as high as 94.2%, while the total agreement rates for the FIGO three-tier and Parer five-tier systems were 69.7% and 67.7%, respectively. In the interpretation of EFHR tracings for acidosis cases, the interobserver agreement for the Parer five-tier system was excellent [Kappa (95% CI): 0.87 (0.79-0.95)], while both the NICHD three-tier and FIGO three-tier systems showed good agreement [Kappa (95% CI): 0.77 (0.66-0.88) and 0.72 (0.60-0.84)]. Conclusions:The Parer five-tier and the FIGO three-tier systems have higher sensitivity in identifying neonatal acidosis than the NICHD three-tier system, and the Parer five-tier system achieves a higher negative predictive value and a greater agreement in the interpretation of pathological EFM patterns.

Objective:To investigate the surgical situations and perioperative outcome of pancreaticoduodenectomy in Jiangsu Province and the influencing factors for postoperative 90-day mortality.Methods:The retrospective case-control study was conducted. The clinicopathological data of 2 886 patients who underwent pancreaticoduodenectomy in 21 large tertiary hospitals of Jiangsu Quality Control Center for Pancreatic Diseases, including The First Affiliated Hospital of Nanjing Medical University, from March 2021 to December 2022 were collected. There were 1 732 males and 1 154 females, aged 65(57,71)years. Under the framework of the Jiangsu Provincial Pancreatic Disease Quality Control Project, the Jiangsu Quality Control Center for Pancreatic Diseases adopted a multi-center registration research method to establish a provincial electronic database for pancrea-ticoduodenectomy. Observation indicators: (1) clinical characteristics; (2) intraoperative and post-operative conditions; (3) influencing factors for 90-day mortality after pancreaticoduodenectomy. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(IQR), and comparison between groups was conducted using the Mann-Whitney U test. Count data were expressed as absolute numbers or constituent ratio, and comparison between groups was conducted using the chi-square test, continuity correction chi-square test and Fisher exact probability. Maximal Youden index method was used to determine the cutoff value of continuous variables. Univariate analysis was performed using the corresponding statistical methods based on data types. Multivariate analysis was performed using the Logistic multiple regression model. Results:(1) Clinical characteristics. Of the 2 886 patients who underwent pancreaticoduodenectomy, there were 1 175 and 1 711 cases in 2021 and 2022, respectively. Of the 21 hospitals, 8 hospitals had an average annual surgical volume of <36 cases for pancreaticoduodenectomy, 10 hospitals had an average annual surgical volume of 36-119 cases, and 3 hospitals had an average annual surgical volume of ≥120 cases. There were 2 584 cases performed pancreaticoduodenectomy in thirteen hospitals with an average annual surgical volume of ≥36 cases, accounting for 89.536%(2 584/2 886)of the total cases. There were 1 357 cases performed pancrea-ticoduodenectomy in three hospitals with an average annual surgical volume of ≥120 cases, accounting for 47.020%(1 357/2 886) of the total cases. (2) Intraoperative and postoperative conditions. Of the 2 886 patients, the surgical approach was open surgery in 2 397 cases, minimally invasive surgery in 488 cases, and it is unknown in 1 case. The pylorus was preserved in 871 cases, not preserved in 1 952 cases, and it is unknown in 63 cases. Combined organ resection was performed in 305 cases (including vascular resection in 209 cases), not combined organ resection in 2 579 cases, and it is unknown in 2 cases. The operation time of 2 885 patients was 290(115)minutes, the volume of intra-operative blood loss of 2 882 patients was 240(250)mL, and the intraoperative blood transfusion rate of 2 880 patients was 27.153%(782/2 880). Of the 2 886 patients, the invasive treatment rate was 11.342%(327/2 883), the unplanned Intensive Care Unit (ICU) treatment rate was 3.087%(89/2 883), the reoperation rate was 1.590%(45/2 830), the duration of postoperative hospital stay was 17(11)days, the hospitalization mortality rate was 0.798%(23/2 882), and the failure rate of rescue data in 2 083 cases with severe complications was 6.529%(19/291). There were 2 477 patients receiving postoperative 90-day follow-up, with the 90-day mortality of 2.705%(67/2477). The total incidence rate of complication in 2 886 patients was 58.997%(1 423/2 412). The incidence rate of severe complication was 13.970%(291/2 083). The comprehensive complication index was 8.7(22.6) in 2 078 patients. (3) Influencing factors for 90-day mortality after pancreaticoduodenectomy. Results of multivariate analysis showed that age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment were independent risk factors for 90-day mortality after pancreaticoduodenectomy ( odds ratio=2.403, 2.609, 16.141, 95% confidence interval as 1.281-4.510, 1.298-5.244, 7.119-36.596, P<0.05). Average annual surgical volume ≥36 cases in the hospital was an independent protective factor for 90-day mortality after pancreaticoduodenectomy ( odds ratio=0.368, 95% confidence interval as 0.168-0.808, P<0.05). Conclusions:Pancreaticoduodenectomy in Jiangsu Province is highly con-centrated in some hospitals, with a high incidence of postoperative complications, and the risk of postoperative 90-day mortality is significant higher than that of hospitallization mortality. Age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment are independent risk factors for 90-day motality after pancreaticoduodenectomy, and average annual surgical volume ≥36 cases in the hospital is an independent protective factor.

Based on the perspective of medical equipment safety culture,analyze the Global Patient Safety Report 2024 released by the World Health Organization(WHO)on May 30,and extract patient safety elements related to medical devices.Propose to initiate action plan for patient safety related to medical devices and discuss the pathway and measures to further ensure patient safety and strengthen safety management in the clinical use of medical devices,in conjunction with promoting high-quality development of hospitals.

Objective:To construct a prognostic nomogram based on epithelial-stromal interaction protein 1(EPSTI1)and predict the pro-gnosis of clear cell renal cell carcinoma(ccRCC).Methods:A retrospective analysis was performed from January 2012 to December 2015 at The First Affiliated Hospital of Fujian Medical University,on 221 patients with ccRCC who underwent surgical treatment in our center and 533 patients with ccRCC in The Cancer Genome Atlas(TCGA)database.Immunohistochemical(IHC)staining was performed on adjacent nor-mal and cancerous tissues to analyze the expression level of EPSTI1 and its correlation with clinicopathological characteristics.Kaplan-Meier survival analysis was performed for the overall survival(OS)and disease-free survival(DFS)of patients with high and low EPSTI1 expression levels.Univariate and multivariate Cox proportional hazards models were used to analyze the prognostic factors for OS,and a nomogram model was constructed and verified.Results:The IHC scores and mRNA expression levels of EPSTI1 were significantly higher in ccRCC tissues than in normal tissues(all P<0.001).EPSTI1 was expressed at higher levels in cancer tissues at higher T stages(P=0.036,P=0.006).The EPSTI1 protein expression level was related to the maximum tumor diameter and TNM stage(P=0.002,P=0.032,respectively).The OS and DFS were higher in the low-EPSTI1-expression group than the high-EPSTI1-expression group(P=0.046,P=0.003,P=0.001).Univariate and multivariate Cox regression analyses showed that a high EPSTI1 protein expression level,WHO/ISUP grade,and AJCC/TNM stage were independent risk factors for poor prognosis(P=0.009,P=0.039,P<0.001).The prognostic nomogram model constructed based on the above variables was su-perior to the AJCC/TNM stage in predicting the 5-year OS,and the calibration curve showed that the predicted value of the model was con-sistent with the actual value.Conclusions:The nomographic model based on EPSTI1,AJCC/TNM staging and WHO/ISUP staging has a strong predictive ability for the prognosis of renal clear cell carcinoma.

Traumatic supraorbital fissure syndrome (TSOFS) is a symptom complex caused by nerve entrapment in the supraorbital fissure after skull base trauma. If the compressed cranial nerve in the supraorbital fissure is not decompressed surgically, ptosis, diplopia and eye movement disorder may exist for a long time and seriously affect the patients′ quality of life. Since its overall incidence is not high, it is not familiarized with the majority of neurosurgeons and some TSOFS may be complicated with skull base vascular injury. If the supraorbital fissure surgery is performed without treatment of vascular injury, it may cause massive hemorrhage, and disability and even life-threatening in severe cases. At present, there is no consensus or guideline on the diagnosis and treatment of TSOFS that can be referred to both domestically and internationally. To improve the understanding of TSOFS among clinical physicians and establish standardized diagnosis and treatment plans, the Skull Base Trauma Group of the Neurorepair Professional Committee of the Chinese Medical Doctor Association, Neurotrauma Group of the Neurosurgery Branch of the Chinese Medical Association, Neurotrauma Group of the Traumatology Branch of the Chinese Medical Association, and Editorial Committee of Chinese Journal of Trauma organized relevant experts to formulate Chinese expert consensus on the diagnosis and treatment of traumatic supraorbital fissure syndrome ( version 2024) based on evidence of evidence-based medicine and clinical experience of diagnosis and treatment. This consensus puts forward 12 recommendations on the diagnosis, classification, treatment, efficacy evaluation and follow-up of TSOFS, aiming to provide references for neurosurgeons from hospitals of all levels to standardize the diagnosis and treatment of TSOFS.

Objective:To investigate the change of collagen fibers in locally recurrent esophageal squamous cell carcinoma after radical chemoradiotherapy and the discrepancy of adverse effects and survival outcomes among groups with different salvage treatments, provide references for the options of salvage therapy.Methods:Medical records of 137 patients with esophageal squamous cell carcinoma who received radical chemoradiotherapy and had local recurrence admitted to Cancer Center of Renmin Hospital of Wuhan University from January 2015 to September 2022 were retrospectively collected. The expression of collagen fibers in paraffin samples of cases with different recurrence time was determined by Masson staining, and the differences of the average optical density were calculated. According to the salvage treatment after local recurrence, all cases were divided into the salvage surgery group, second-course chemoradiotherapy group and immunochemotherapy group. The differences of survival outcomes and incidence rates of esophageal tracheal fistula, hemorrhage, pericardial effusion, radiation pneumonitis, radiation esophagitis were analyzed among the three groups. The differences of survival rates were analyzed by Kaplan-Meier method and compared by log-rank test among groups.Results:The expression of collagen fibers in recurrent esophageal squamous cell carcinoma was significantly higher than that in primary esophageal squamous cell carcinoma. Collagen fiber expression was gradually down-regulated with the prolongation of recurrence time. The expression of collagen fibers in recurrent cases after 7 years was similar to that of primary esophageal squamous cell carcinoma. The 1-, 2- and 3-year survival rates of patients in the salvage surgery group, the second-course chemoradiotherapy group and the immunochemotherapy group were 47%, 30%, 20%; 50%, 27%, 15% and 72.5%, 50%, 50%, respectively; Immunochemotherapy was more effective in salvage treatment for recurrent esophageal squamous cell carcinoma, but there was no statistical difference.Conclusions:Collagen fibers are abundant in recurrent esophageal squamous cell carcinoma after radical chemoradiotherapy. With prolongation of recurrent interval, the expression of collagen fibers is down-regulated. The survival outcomes of patients in the immunochemotherapy group, salvage surgery group and second-course chemoradiotherapy group were comparable.

In recent years,the isolation rate of carbapenem-resistant Klebsiella pneunoniae(CRKP)in China has increased year by year.Due to its multidrug resistance and high mortality in patients,CRKP brings severe challen-ges to the clinical treatment.The major mechanism of drug resistance in CRKP is the production of carbapenemases,with Ambler A,B,and D being the common types while Ambler type C comparativly rare.Klebsiella pneumoniae carbapenemase(KPC)is the most common carbapenemase,which belongs to type A.KPC-producing Klebsiella pneumoniae(KPC-KP)widely spreads in the world,with very limited number of effective clinical drugs.In this re-view,advances in the treatment KPC-KP were summarized to provide reference for clinical treatment.

Objective To explore the safety and feasibility of intravenous dexmedetomidine(Dex)combined with targeted infusion of remifentanil in endoscopic retrograde cholangiopancreatography(ERCP)anesthesia in older adult patients.Methods From January to August 2021,98 older adult patients(≥65 years old)undergoing ERCP were randomly divided into TRP and TRD groups.The TRP group was anesthetized with target-controlled infusion of propofol and remifentanil and the TRD group was treated with Dex combined with target-controlled infusion of remifentanil.mean arterial pressure(MAP),heart rate(HR),electrocardiogram(ECG),respiratory rate(RR),pulse oxygen saturation(SpO2),bispectral index(BIS)before anesthesia induction(T0),immediately after induction of anesthesia(T1),endoscopic introduction(T2),duodenal papilla intubation(T3),endoscopy withdrawal(T4)and postoperative awakening(T5)were observed.Arterial blood gas analysis at different time points(T0,every 15 min after anesthesia induction and T5),PaO2,and PaCO2,were recorded at the above mentioned time points;and the remifentanil concentration in target-controlled infusion,operation time,recovery time(from infusion of remifentanil to consciousness recovery),anesthesia recovery time(from consciousness recovery to leaving the operating room),intraoperative body movement,Aldrete scores out of the room,Visual Analogue Scale(VAS)at 60 min after surgery,occurrence of post-operative adverse reactions,as well as the satisfaction of anesthesiologists,endoscopists,and patients were recorded.Results Compared with the TRP group,MAP at T1 and T3,SpO2 and RR at T1,T2,T3,and T4,and BIS at T2,T3,T4,and T5 increased,whereas HR at T1,T2,T3,and T4 decreased;the number of mandibular rests,incidence of hypoxemia,Aldrete score,and satisfaction increased,whereas the VAS score at 60 min after surgery decreased in the TRD group(P<0.05).There were no statistically significant differences in postoperative adverse reactions,PaO2 and PaCO2,target-controlled infusion remifentanil concentration,operation time,recovery time,and anesthesia recovery time between the two groups.Conclusion Compared with the target-controlled infusion of propofol-remifentanil,intravenous infusion of Dex combined with target-controlled infusion of remifentanil can reduce the incidence of hypoxemia in older adult patients during ERCP surgery,and the anesthesia regimen can meet the anesthesia needs of ERCP surgery,which is safe and feasible.