Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

Objective To explore the clinical value of artificial intelligence (AI) quantitative parameters in distinguishing pathological grades of stageⅠ invasive adenocarcinoma (IAC). Methods Clinical data of patients with clinical stageⅠ IAC admitted to Yantaishan Hospital Affiliated to Binzhou Medical University from October 2018 to May 2023 were retrospectively analyzed. Based on the 2021 WHO pathological grading criteria for lung adenocarcinoma, IAC was divided into gradeⅠ, grade Ⅱ, and grade Ⅲ. The differences in parameters among the groups were compared, and logistic regression analysis was used to evaluate the predictive efficacy of AI quantitative parameters for grade Ⅲ IAC patients. Parameters were screened using least absolute shrinkage and selection operator (LASSO) regression analysis. Three machine learning models were constructed based on these parameters to predict grade Ⅲ IAC and were internally validated to assess their efficacy. Nomograms were used for visualization. Results A total of 261 IAC patients were included, including 101 males and 160 females, with an average age of 27-88 (61.96±9.17) years. Six patients had dual primary lesions, and different lesions from the same patient were analyzed as independent samples. There were 48 patients of gradeⅠ IAC, 89 patients of grade Ⅱ IAC, and 130 patients of grade Ⅲ IAC. There were statitical differences in the AI quantitive parameters such as consolidation/tumor ratio (CTR), ect among the three goups. (P<0.05). Univariate analysis showed that the differences in all variables except age were statistically significant (P<0.05) between the group gradeⅠ+grade Ⅱand the group grade Ⅲ . Multivariate analysis suggested that CTR and CT standard deviation were independent risk factors for identifying grade Ⅲ IAC, and the two were negatively correlated. Grade Ⅲ IAC exhibited advanced TNM staging, more pathological high-risk factors, higher lymph node metastasis rate, and higher proportion of advanced structure. CTR was positively correlated with the proportion of advanced structures in all patients. This correlation was also observed in grade Ⅲ but not in gradeⅠand grade ⅡIAC. CTR and CT median value were selected by using LASSO regression. Logistic regression, random forest, and XGBoost models were constructed and validated, among which, the XGBoost model demonstrated the best predictive performance. Conclusion Cautious consideration should be given to grade Ⅲ IAC when CTR is higher than 39.48% and CT standard deviation is less than 122.75 HU. The XGBoost model based on combined CTR and CT median value has good predictive efficacy for grade Ⅲ IAC, aiding clinicians in making personalized clinical decisions.

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.

Cognitive frailty is a reversible neurodegeneration, and its early identification and prevention are crucial. This paper summarizes the current situation, risk factors, and risk prediction models of cognitive frailty in elderly patients with chronic diseases, aiming to provide a reference for clinical medical and nursing staff to identify the risk of cognitive frailty in elderly patients with chronic diseases as early as possible and formulate intervention measures.

Objective:To observe the clinical effect of initiating continuous blood purification (CBP) treatment at different times for patients with severe acute pancreatitis (SAP), and to explore the optimal timing for starting CBP treatment for SAP, so as to provide evidence for clinicians to start CBP treatment.Methods:A retrospective cohort study was used to select patients with SAP who received CBP treatment in People's Hospital of Hunan Province from January 2020 to December 2023. According to the timing of CBP initiation, the patients were divided into early initiation group (diagnosis of SAP to the first CBP treatment time < 24 hours) and late initiation group (diagnosis of SAP to the first CBP treatment time of 24-48 hours). The general data, acute physiology and chronic health evaluationⅡ(APACHEⅡ), bedside index for severity in acute pancreatitis (BISAP) score and laboratory indicators, local complications and systemic complications, intensive care unit (ICU) treatment time, hospital stay, treatment cost, and clinical outcome of the two groups were collected and compared.Results:A total of 130 patients with SAP who received CBP treatment were enrolled, including 90 patients in the early initiation group and 40 patients in the late initiation group. Before treatment, there were no significant differences in gender, age, APACHEⅡscore, BISAP score, etiology and laboratory examination indexes between the early initiation group and late initiation group. At 48, 72, 96 hours after treatment, the blood calcium level of the two groups was significantly higher than that before treatment, and the levels of white blood cell count (WBC), C-reactive protein (CRP), lactic acid, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), APACHEⅡscore and BISAP score were significantly lower than those before treatment. The WBC level, APACHEⅡscore and BISAP score of the late initiation group were significantly lower than those of the early initiation group at 72 hours and 96 hours after treatment [WBC (×10 9/L): 10.96 (8.68, 13.04) vs. 12.45 (8.93, 16.30) at 72 hours after treatment, and 10.18 (8.68, 12.42) vs. 11.96 (8.81, 16.87) at 96 hours after treatment; APACHEⅡscore: 9.50 (5.75, 12.00) vs. 11.00 (6.25, 14.00) at 72 hours after treatment, and 10.00 (4.00, 12.00) vs. 12.00 (7.00, 14.75) at 96 hours after treatment; BISAP score: 2.35±1.03 vs. 2.76±1.10 at 72 hours after treatment, and 2.08±1.21 vs. 2.70±1.11 at 96 hours after treatment], the differences were statistically significant (all P < 0.05). In terms of complications, the incidence of pancreatic abscess in the late initiation group was significantly lower than that in the early initiation group [5.00% (2/40) vs. 20.00% (18/90)], but the incidence of abdominal compartment syndrome was significantly higher than that in the early initiation group [42.50% (17/40) vs. 13.33% (12/90)], the differences were statistically significant (all P < 0.05). In addition, the ICU treatment time in the early initiation group was significantly shorter than that in the late initiation group [days: 11.00 (6.00, 20.00) vs. 15.00 (9.75, 25.00), P < 0.05], and there were no statistically significant differences in hospitalization costs, length of stay and mortality between the two groups. Conclusions:CBP can effectively increase the level of blood calcium and decrease the level of lactic acid and inflammatory factors. Starting CBP within 24-48 hours after diagnosis of SAP can reduce WBC level and disease severity score faster, and reduce the occurrence of pancreatic abscess. Initiation of CBP within 24 hours after diagnosis of SAP can reduce the incidence of abdominal compartment syndrome and shorten the duration of ICU treatment.

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of gallic acid,protocatechuic acid,neomangiferin,catechin,caffeic acid,mangiferin,isomangiferin,albiflorin,paeoniflorin,vitexin,liquiritin,scutellarin,baicalin,liquiritigenin,timosaponin BⅡ,quercetin,wogonoside,benzoylpaeoniflorin,isoliquiritigenin,honokiol,magnolol,norarecaidine,arecaidine,arecoline,epicatechin,baicalein,glycyrrhizinate and wogonin in Dayuan Drink.METHODS The analysis was performed on a 35℃thermostatic Syncronis C18 column(100 mm×2.1 mm,1.7 μm),with the mobile phase comprising of 0.1%formic acid-acetonitrile flowing at 0.3 mL/min in a gradient elution manner,and electron spray inoization source was adopted in positive and negative ion scanning with select reaction monitoring mode.RESULTS Twenty-eight constituents showed good linear relationships within their own ranges(R2≥0.991 0),whose average recoveries were 95.60%-103.53%with the RSDs of 0.60%-5.45%.CONCLUSION This rapid,simple,selective,accurate and reliable method can be used for the quality control of Dayuan Drink.

Objective:To treat the Crohn's disease(CD)patients with ustekinumab(UST),to eva-luate their clinical and endoscopic remission,and to evaluate their transmural response(TR)and trans-mural healing(TH)condition using intestinal ultrasonography(IUS).Methods:Retrospective analysis was made on patients diagnosed with CD in Peking University People's Hospital from January 2020 to Au-gust 2022,who were treated with UST for remission induction and maintenance therapy.All the patients were evaluated on both week 8 and week 16/20 after treatment,including clinical,biochemical indica-tors,colonoscopy and IUS examination.Results:A total of 13 patients were enrolled in this study,inclu-ding 11 males and 2 females.The minimum age was 23 years,the maximum age was 73 years and the mean age was 36.92 years.All the patients were in the active stage of disease before treatment,and the average Best Crohn's disease activity index(Best CDAI)score was 270.12±105.55.In week 8,the Best CDAI score of the patients decreased from 270.12±105.55 to 133.16±48.66(t=4.977,P＜0.001).Eight patients achieved clinical remission while 5 patients remained in the active stage.Nine patients underwent colonoscopy evaluation.The average simple endoscopic score for Crohn's disease(SES-CD)score decreased from 10.71±7.14 before treatment to 6.00±7.81(t=2.483,P=0.048)in week 16/20.Four patients achieved endoscopic remission while 5 patients did not.In week 8,5 pa-tients achieved TR,2 patients achieved TH,the other 6 patients did not get TR or TH.In week 16/20,6 patients achieved TR,3 patients achieved TH while the other 4 patients did not get TR or TH.There was no significant statistical difference in the TR effect of UST between small intestine and colon lesions(Fisher test,P＞0.999).The rate of UST transmural response in the patients who had had previous bio-logical agent therapy was lower than those with no previous biological agent therapy,but there was no sig-nificant statistical difference(Fisher test,P=0.491).Conclusion:After treatment of UST,the clinical and endoscopic conditions of the CD patients had been improved,and some patients could achieve clini-cal remission and endoscopic remission.UST had good TR and TH effects on CD.TR might appear in week 8,and the TR effect increased in week 16/20.There was no significant statistical difference in the TR effect between small intestine and colon lesions.TR effect of UST was better in the patients who had no previous biological agent therapy than those who had had other biological agents,but the result had no significant statistical difference.

AIM To evaluate the quality of Beidougen Formula Granules.METHODS Fifteen batches of standard decoctions and three batches of formula granules were prepared,after which paste rate and contents,transfer rates of magnoflorine,daurisoline,dauricine were determined.HPLC specific chromatograms were established,and cluster analysis was adopted in chemical pattern recognition.RESULTS For three batches of formula granules,the paste rates were 15.1%-16.6%,the contents of magnoflorine,daurisoline,dauricine were 18.93-19.39,9.42-9.60,6.79-6.85 mg/g with the transfer rates of 34.42%-35.25%,43.81%-44.65%,27.27%-27.51%from decoction pieces to formula granules,respectively,and there were seven characteristic peaks in the specific chromatograms with the similarities of more than 0.95,which demonstrated good consistence with those of standard decoctions and accorded with related limit requirements.Fifteen batches of standard decoctions were clustered into two types,and the medicinal materials produced from Jilin,Hebei,Shangdong could be used for the preparation of formula granules.CONCLUSION This reasonable and reliable method can provide references for the quality control and clinical application of Beidougen Formula Granules.

Tuberculosis （TB） and human immunodeficiency virus infection / acquired immune deficiency syndrome （HIV/AIDS） are both serious global public health threats. Early detection of infected persons and/or patients through TB/HIV bi-directional screening is crucial for prevention and control strategy in China and globally. In recent years， with the promotion and application of new TB and HIV detection technologies worldwide， TB/HIV bi-directional screening technologies and strategies have made remarkable changes. This expert consensus introduces the significance and challenges of TB/HIV bi-directional screening， summarizes important progress of research and applications， and makes recommendations on screening measures and procedures to further strengthen TB/HIV bi-directional screening in China.

The assessment of adverse drug events is an important basis for clinical safety evaluation and post-marketing risk control of drugs,and its causality assessment is gaining increasing attention.The existing methods for assessing the causal relationship between drugs and the occurrence of adverse reactions can be broadly classified into three categories:global introspective methods,standardized methods,and probabilistic methods.At present,there is no systematic introduction of the operational details of the various methods in the domestic literature.This paper compares representative causality assessment methods in terms of definition and concept,methodological steps,industry evaluation and advantages and disadvantages,clarifies the basic process of determining the causality of adverse drug reactions,and discusses how to further improve the adverse drug reaction monitoring and evaluation system,with a view to providing a reference for drug development and pharmacovigilance work in China.