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 trends of incidence, mortality, and years of life lost (YLL) rate of lung cancer in cancer registration areas of Guizhou Province from 2017 to 2021, so as to provide references for formulating lung cancer prevention and control strategies and reducing the disease burden of lung cancer. Methods: The qualified lung cancer registration data from cancer registration areas of Guizhou Province from 2017 to 2021 were collected, the crude incidence and mortality of lung cancer were calculated by urban/rural areas, genders and ages. The standardized incidence and standardized mortality was calculated using the age structure of the standard population from the Fifth National Population Census in 2000. YLL was calculated using the standard life table from the Global Burden of Disease Study 2019. The disease burden of lung cancer was assessed using incidence, mortality, and YLL rate, and the trend in the disease burden of lung cancer from 2017 to 2021 was calculated using annual percent change (APC). Results : From 2017 to 2021, the crude incidence, standardized incidence, crude mortality, standardized mortality, YLL and YLL rate in Guizhou Province were 53.13/100 000, 37.58/100 000, 42.77/100 000, 29.44/100 000, 98.19 thousand person-years and 10.95‰, respectively. The standardized incidence and standardized mortality of lung cancer were higher in rural areas than in urban areas (39.45/100 000 vs. 34.23/100 000, 30.68/100 000 vs. 27.18/100 000). The standardized incidence and standardized mortality of lung cancer were higher in males than in females (49.34/100 000 vs. 26.47/100 000, 41.31/100 000 vs. 18.28/100 000). The crude incidence and crude mortality of lung cancer increased with age, peaking in the 80-<85 age group (360.84/100 000) and the ≥85 age group (414.85/100 000), respectively. From 2017 to 2021, the standardized incidence demonstrated downward trends in the total population, urban areas and males (APC=-6.590%, -5.829%, and -6.729%, all P<0.05). The standardized mortality demonstrated downward trends in urban areas and females (APC=-3.710% and -5.378%, both P<0.05). The YLL rate also showed downward trends in urban areas and females (APC=-3.957% and -3.631%, both P<0.05). Conclusions From 2017 to 2021, the overall disease burden of lung cancer in registration areas of Guizhou Province showed a decreasing trend. However, the disease burden remained relatively heavier in rural areas and males, with a relatively gradual change.

Aim To investigate the regulatory mecha-nism of butin on the proliferation,migration,cycle blockage and pyroptosis related inflammatory factors in human fibroblast-like synoviocytes of rheumatoid arthri-tis(HFLS-RA).Methods Cell proliferation,migra-tion and invasion were studied using cell migration and invasion assays.Cell cycle was detected by flow cytom-etry,and the expression of the pyroptosis-associated in-flammatory factors IL-1β,IL-18,caspase-1 and caspase-3 was detected by ELISA,RT-qPCR and West-ern blot.Results Migration and invasion experiments showed that the cell proliferation rate of the butin group was lower than that of the blank control group(P＜0.05).Cell cycle analysis demonstrated that in the G0/G1 phase,the DNA expression was elevated in the medium and high-dose groups of butin(P＜0.05),while in the G2 and S phases,the DNA expression was reduced in the medium and high-dose groups of butin(P＜0.05).The results of ELISA,RT-qPCR and Western blot assay revealed that the expression of IL-1β,IL-1 8,caspase-1,and caspase-3 decreased in the butin group compared with the IL-1β+caspase-3 in-hibitor group(P＜0.05).Conclusions Butin inhib-its HFLS-RA proliferation by inhibiting the synthesis of inflammatory vesicles by caspase-1 in the pyroptosis pathway,thereby reducing the production and release of inflammatory factors such as IL-1β and IL-18 down-stream of the pathway,and also inhibits HFLS-RA pro-liferation by exerting a significant blocking effect in the G1 phase,which may be one of the potential mecha-nisms of butin in the treatment of RA.

Objective To compare screw versus Kirschner wire fixation in the treatment of lateral humeral condyle frac-tures in children.Methods A systematic search was conducted in PubMed,Embase,the Cochrane library,Web of Science,China National Knowledge Internet(CNKI),Wanfang Datebase from in ception to February 2022.Studies comparing screws and Kirschner wire fixation in the treatment of lateral humeral condyle fractures in children were included.Outcome measures included and excluded by a set of inclusion and exclusion criteria and evaluated for their quality,their excellent and good rate of fracture healing,malunion,delayed union or nonunion,infection,limitation of elbow flexion or extension(＞10°)were ex-tracted and analyzed using software Rev Man 5.3.Results A total of 9 retrospective studies involving 647 patients were includ-ed,with 255 patients in the screw fixation group(including screw combined with Kirschner wire)and 392 patients in the Kirschner wire fixation group.Meta analysis showed the following:infection rate in the screw group was significantly lower than that in the Kirschner wire group[OR=0.22,95％CI(0.09,0.56),P=0.001].There were no significant differences between the 2 groups in excellent and good rate of fracture healing,malunion rate(P＞0.05).Subgroup analysis showed that infection rate in the screw-only group was significantly lower than that in the Kirschner wire group[OR=0.18,95％CI(0.05,0.65),P=0.009].Conclusion For lateral humeral condyle fractures,Screw fixation alone had a lower infection rate than kirschner wire fixation and screw combined with Kirschner wire fixation.There were no significant differences in the excellent and good rate of fracture healing,malunion.In terms of postoperative efficacy and safety of internal fixation,orthopaedic surgeons are more like-ly to recommend screws for fixation of lateral humeral condyle fractures in children.

Objective:To compare the diagnostic efficacy of 22 G fine needle aspiration (FNA) needles and 22 G end-cutting fine needle biopsy (FNB) needles for solid pancreatic lesion using both cytological and histological examination.Methods:Clinical data of 116 patients who underwent endoscopic ultrasound-guided fine needle aspiration/biopsy (EUS-FNA/FNB) at the Digestive Endoscopy Center of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from June 2022 to March 2023 were retrospectively analyzed. Sixty-three patients sampled with 22 G FNA needles were the FNA group, and 53 sampled with 22 G FNB needles were the FNB group. The diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and cytological and histological diagnostic yield of FNA needles and FNB needles for solid pancreatic lesions were compared.Results:There were no significant differences in age, gender, lesion location, lesion size, or the number of passes between the FNA group and the FNB group ( P>0.05). There were no significant differences in the diagnostic accuracy [93.7% (59/63) VS 90.6% (48/53), P=0.730], sensitivity [93.0% (53/57) VS 90.2% (46/51), P=0.732], specificity [100.0% (6/6) VS 100.0% (2/2), P=1.000], positive predictive value [100.0% (53/53) VS 100.0% (46/46), P=1.000] and negative predictive value [60.0% (6/10) VS 28.6% (2/7), P=0.335] of combined cytology and histology in distinguishing benign and malignant lesions between the two groups. In the FNA group, the diagnostic accuracy of combined cytology and histology was higher than cytology alone [93.7% (59/63) VS 81.0% (51/63), P=0.008], and was higher than histology alone without statistical significance [93.7% (59/63) VS 87.3% (55/63), P=0.125]. In the FNB group, the diagnostic accuracy of combined cytology and histology was higher than cytology alone [90.6% (48/53) VS 69.8% (37/53), P=0.001], but not than histology alone [90.6% (48/53) VS 90.6% (48/53)， P=1.000]. For solid masses located in pancreatic body/tail, the diagnostic accuracy for malignancy by histology using FNB needles tended to be higher than that of FNA needles [100.0% (17/17) VS 81.3% (26/32), P=0.080]. Conclusion:Both FNA needles and FNB needles exhibit adequate diagnostic yield for solid pancreatic masses when combining cytology and histology. FNB needles may offer a higher histological diagnostic yield.

Objective To construct a mouse model of psoriasis with spleen deficiency and dampness obstruction pattern and evaluate the model from multiple dimensions and directions,expects to provide research support for the study of traditional Chinese medicine (TCM) treatment of psoriasis with spleen deficiency and dampness obstruction pattern. Methods A mouse model of spleen deficiency and dampness obstruction pattern was established by feeding a high-fat diet,a mouse model of psoriasis vulgaris was established by externally applying imiquimod ointment,and a mouse model of psoriasis with spleen deficiency and dampness obstruction pattern was constructed by combining the above two models. Indications of spleen deficiency and dampness obstruction pattern were evaluated by comparing the body mass,food intake and water intake of mice in each group. The severity of psoriasis in mice was evaluated by comparing the area of skin lesions,PASI score,the value of transdermal water loss (TEWL),and histopathological morphological changes of skin under HE staining in each group. Flow cytometry was used to detect the expression in various cell types to evaluate the degree of inflammatory response of psoriasis in mice. Observation of adiposity index,changes in the histopathological morphology of liver tissue under HE staining,changes in the mRNA expression levels of related factors in liver tissue and adipose tissue of epididymis of mice detected by RT-qPCR,and changes of ABCA1 protein expression level of skin detected by Western Blot were used to evaluate the lipid metabolism disorders in mice. Results Compared with the mice in the psoriasis vulgaris model group,the mice in the model of psoriasis with pattern of spleen deficiency and dampness obstruction had significantly higher body mass (P<0.001),significantly lower food intake (P<0.005),and the symptoms of pattern of spleen deficiency and dampness obstruction such as greasy fur,mental fatigue,etc. appeared. The TWEL were significantly increased(P<0.001),and the PASI scores also significantly increased(P<0.001). HE results were found psoriasis-like manifestations including hypertrophy of the spinous layer and clubbed hyperplasia. The expression of CD11bhighLy6G+neutrophil subpopulation,CD11binLy6Chigh monocyte subpopulation,CD11binCD11chigh classical dendritic cell subpopulation,F4/80-CD11c+dendritic cell subpopulation was significantly increased (P<0.001). HE staining suggested that the cellular morphology of liver showed obvious vacuolated degeneration,and the index of subcutaneous white adiposity and epididymal adiposity index were both significantly increased (P<0.005). The mRNA levels of FABP4 and CD36 in liver tissue were significantly elevated(P<0.005,P<0.001),while the mRNA expression levels of ABCA1 and PPARγ in epididymal fat tissue were decreased (P<0.05,P<0.01). ABCA1 protein level in skin increased(P>0.05). Conclusion The mouse model of psoriasis with spleen deficiency and dampness obstruction pattern can be used as a reliable animal model for combining disease and pattern,which can provide a reference for further exploration of TCM in the treatment of psoriasis with spleen deficiency and dampness obstruction pattern.

Objective The objective of this study was to establish a mouse model of allergic rhinoconjunctivitis and investigate the role of the NLRP3 signaling pathway in allergic rhinoconjunctivitis.Methods Thirty-three female C57 mice(SPF)were randomLy divided into 3 groups:the control group,the experimental group,and the NLRP3-/-group.On days 0,4,7,14,and 21,the experimental group and NLRP3-/-group received a 0.2 mL intraperitoneal injection of medicine containing OVA(100 μg)and adjuvant Al(OH)3(4 mg),respectively.After an interval of 3 days,each eye and nose were dosed with 10 μL of 5%OVA for five consecutive days a week to induce allergic symptoms.During sensitization and excitation stages,the control group was replaced with an equiva-lent amount of PBS.Ocular and nasal symptoms were observed and scored.The levels of OVA-specific IgE,IL-4,IL-17,and IL-18 in serum were measured using ELISA,while changes in palpebral conjunctiva and nasal mucosa were assessed by hematoxylin-eosin staining.The expression of NLRP3 mRNA in conjunctival tissue and nasal mucosa was determined using real-time PCR analysis.Statistical analysis was performed using SPSS17.0 software with P<0.05 considered as statistically significant difference.Results The experimental group and NLRP3-/-group exhibited induced nasal and ocular allergic symptoms.In the experimental group,the duration of nasal allergy symptoms was(10.500±1.080)days,while the duration of eye allergy symptoms was(20.300±2.058)days.In the NLRP3-/-group,the duration of nasal allergy symptoms was(13.400±1.955)days,and for eye allergy symp-toms it was(20.900±2.132)days.The duration of nasal allergies in the NLRP3-/-group significantly exceeded that in the experimental group(P<0.05),whereas there were no significant differences observed in eye allergy durations between these two groups(P>0.05).Levels of OVA-specific IgE,IL-4,and IL-17 were significantly higher in both the experimental and NLRP3-/-groups compared to those in the control group(P<0.05).Additionally,serum IL-18 content increased significantly in the experimental group when compared with both control and NLRP3-/-groups(P<0.05).Conjunctival tissue lesions as well as nasal mucosa damage were evident in both experimental and NLRP3-/-groups.mRNA expression levels of NLRP3 within conjunctival tissue and nasal mucosa from the experimental group showed a significant increase when compared to those from both control and NLRP3-/-groups(P<0.05).Conclusion Allergic rhinoconjunctivitis pathogenesis is influenced by various factors;however,the involvement of NLPR3 signaling pathway promotes its development.

The construction of a medication safety culture is important for medication safety management and rational drug use.The construction of medication safety culture standards is formulated based on relevant national policies and regulations,accreditation standards for hospitals,expert opinions,the current situation,and the development trend of the healthcare industry.With scientificity,general applicability,instructive guidance,and practicality,they standardized basic requirements,management processes,and improvement of the construction of medication safety culture.To facilitate understanding and the implementation of the standards,we describe the process of standards formulation and explain the key points of the standards.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Aim To establish a stable hepatic stellate cell ( HSC ) -specific G protein-coupled receptor kinase 2 ( GRK2 ) knockout mice and provide the important animal model for further studying the biological function of GRK2 in HSC. Methods The loxP-labeled Grk2 gene mouse (Grk2