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.

A growing body of research points out that gut microbiota plays a key role in tumor immunotherapy. By optimizing the composition of intestinal microbiota, it is possible to effectively improve immunotherapy resistance and enhance its therapeutic effect. This article comprehensively analyzes the mechanism of intestinal microbiota influencing tumor immunotherapy resistance, expounds the current strategies for targeted regulation of intestinal microbiota, such as traditional Chinese medicine and plant components, fecal microbiota transplantation, probiotics, prebiotics and dietary therapy, and explores the potential mechanisms of these strategies to improve patients' resistance to tumor immunotherapy. At the same time, the article also briefly discusses the prospects and challenges of targeting intestinal microbiota to improve tumor immunotherapy resistance, which provides a reference for related research to help the strategy research of reversing tumor immunotherapy resistance.

Objective To investigate the effects of fractionated low-dose ionizing radiation (LDIR) on the ferroptosis in human bronchial epithelial (HBE) cells as well as the associated differentially expressed genes (DEGs), biological processes, and signaling pathways. Methods HBE cells were exposed to different single doses of X-ray irradiation (0, 25, 50, 75, and 100 mGy) for 24, 48, and 72 h, respectively. The change in cell viability was detected by MTT assay. Cells were irradiated with 0, 25, 50, and 100 mGy X-rays 5 times, with 48 h between each irradiation and a dose rate of 50 mGy/min. Cells were harvested 24 h after irradiation for the measurement of the expression of ferroptosis-related genes SLC7A11 and GPX4 at the mRNA and protein levels, cellular iron content, and the expression of FTH1 and FTL mRNAs. High-throughput sequencing was used to screen for the DEGs in each dose group, followed by Gene Ontology-Biological Process (GO-BP) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Set Enrichment Analysis (GSEA). Results Compared with the control group, single-dose LDIR significantly increased cell proliferation at 75 mGy after 24 h (P < 0.05), at 50, 75, and 100 mGy after 48 h (P < 0.05), and at 75 and 100 mGy after 72 h (P < 0.05). Compared with the control group, at the end of the fifth fractionated LDIR, SLC7A11 and GPX4 mRNAs decreased at all doses (P < 0.05), SLC7A11 protein decreased at all doses, GPX4 protein decreased at 25 and 100 mGy, iron content increased at all doses, and FTH1 and FTL mRNAs decreased at all doses (P< 0.05). Sequencing analysis identified 248, 30, and 291 DEGs and 10, 2, and 9 ferroptosis-associated genes at the three doses compared to the control. Gene Ontology-Biological Process analysis showed that DEGs were mainly enriched in biological processes such as response to lipids, cell death, and response to unfolded proteins. Kyoto Encyclopedia of Genes and Genomes analysis showed that DEGs were mainly enriched in the JAK-STAT signaling pathway, lipids and atherosclerosis, ferroptosis, protein processing in the endoplasmic reticulum, and FoxO signaling pathway. Gene set enrichment analysis showed that DEGs were mainly enriched in ferroptosis, fatty acid degradation, and glutathione metabolism. Conclusion Fractionated low-dose radiation induced ferroptosis in HBE cells, and DEGs were predominantly enriched in biological processes and signaling pathways related to inflammation, ferroptosis, and endoplasmic reticulum stress.

Background In recent years, the increasingly widespread application of nuclear and medical radiation technologies has resulted in a large number of occupational populations exposed to low-dose ionizing radiation (LDIR). At present, there is no consistent conclusion on the effects of long-term exposure to LDIR on the metabolic health of the occupational population. Objective To explore the association between long-term exposure to LDIR and metabolic syndrome (MetS) among medical radiologists. Methods A cross-sectional study was conducted to enroll 6431 medical radiologists who ordered occupational health checkups from January 2022 to December 2023, and basic information such as demographic characteristics, occupational characteristics, lifestyles, and dietary habits was collected through questionnaires. Physical examinations were conducted using a standardized protocol. Individual dose equivalents of occupational external exposure were monitored by dosimeters worn by medical radiologists. Logistic regression model was used for identifying influencing factors of MetS and sensitivity analysis, and restricted cubic spline model was used to explore the dose-response relationship between cumulative effective dose and MetS. Two-stage linear regression was used to evaluate threshold effect of association between cumulative effective dose and MetS. Results The positive rate of MetS was 13.6% (877/6431) among the enrolled 6431 study participants. The logistic regression showed that gender, age, monthly income, body mass index (BMI), cumulative effective dose, and smoking were influencing factors for MetS. The risk of MetS was higher in males (OR=1.511, 95%CI: 1.209, 1.888); using the < 30 years old group as reference, the risk of MetS was higher in the 30-39 years old (OR=1.509, 95%CI: 1.095, 2.079), 40-49 years old (OR=2.214, 95%CI: 1.551, 3.161), and ≥50 years old (OR=3.480, 95%CI: 2.338, 5.181) groups; using the <10000 yuan group as reference, the risk of MetS was lower in the group with a monthly income of 10000-14999 yuan (OR=0.715, 95%CI: 0.582, 0.878); the risk of MetS was higher in the BMI ≥ 24 kg·m⁻² group (OR=7.548, 95%CI: 6.223, 9.156); using the < 0.76 mSv group as reference, the risk of MetS was higher in the cumulative effective dose of 0.76-2.73 mSv group (OR=1.270, 95%CI: 1.017, 1.586); the risk of MetS was higher in the smoking group (OR=1.734, 95%CI: 1.428, 2.107). The results of restricted cubic spline showed that the cumulative effective dose was nonlinearly correlated with MetS (P _{non-linearity}=0.028), with an inflection point of 1.25 mSv. The risk of developing MetS increased by 34.1% for each unit increase in cumulative effective dose up to 1.25 mSv, whereas above 1.25 mSv, the statistical association was not significant. The sensitivity analysis results showed that after excluding the self-reported hypertensive and diabetic patients, the cumulative effective dose 0.76-2.73 mSv group still had an increased risk of developing MetS compared with the < 0.76 mSv group (P < 0.05), and the results were robust. Conclusion Among medical radiologists, male, age, BMI, and smoking are positively correlated with MetS, and monthly income is negatively correlated with MetS; cumulative effective dose is non-linearly correlated with MetS among medical radiologists.

Objective To investigate the induction of senescence in L02 hepatocytes by low-dose fractionated X-ray radiation and its effects on oxidative stress, oxidative damage, and nuclear factor-κB (NF-κB) pathway protein levels. Methods L02 cells were subjected to fractionated X-ray irradiation at doses of 0.1, 0.2, and 0.5 Gy per fraction for a total of six fractions. Assays were performed 24 hours after the final irradiation. Measurements included SA-β-gal staining, the mRNAs of senescence-related genes p53 and p21 and their encoded proteins, mRNAs of genes encoding senescence-associated secretory phenotype factors (IL-6, IL-8, GM-CSF, MMP-15), reactive oxygen species, oxidative and anti-oxidative markers (malondialdehyde, glutathione, superoxide dismutase), DNA oxidative damage markers (8-OHdG and γ-H2AX), and NF-κB pathway protein levels. Results Compared with the control group, at 24 hours after the end of six irradiations, the number of cells positive in SA-β-gal staining was significantly increased in all dose groups. The mRNA and protein levels of p21 and p53 were significantly elevated in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The mRNA levels of genes encoding IL-6, GM-CSF, and MMP-15 were significantly increased in all dose groups (P < 0.05). The mRNA levels of the gene encoding IL-8 were significantly increased in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The levels of reactive oxygen species, malondialdehyde, and glutathione were significantly increased in all dose groups (P < 0.01). The level of superoxide dismutase was significantly increased in the 0.5 Gy × 6 group (P < 0.01). The levels of 8-OHdG were significantly increased in all dose groups (P < 0.05). In both the 0.2 Gy × 6 and 0.5 Gy × 6 groups, the expression levels of γ-H2AX and p-NF-κB p65 were significantly increased (P < 0.05), and the levels of IκBα were significantly decreased (P < 0.05). Conclusion Low-dose fractionated X-ray radiation can induce senescence and cause alterations in oxidative stress, oxidative damage, and the levels of NF-κB pathway proteins in L02 hepatocytes.

Objective To analyze the risk of adverse drug events in pediatric clinical applications of tocilizumab versus inflixima.Methods Adverse event(AE)reporting data for tocilizumab versus infliximab in the U.S.Food and Drug Administration Adverse Event Reporting System database for the pediatric population from Q1 2013 to Q1 2023 were collected.AE risk signal mining was performed using the reporting odds ratio(ROR)method and the proportional reporting ratio(PRR)method.AEs were also classified and statistically analyzed according to the preferred system organ classification and preferred terminology(PT)of the International Dictionary of Medical Terminology.Results Data were extracted and cleaned to include 1 052 AE reports with 198 positive PT signals for tocilizumab as the suspected drug and 9 1 39 AE reports with 387 positive PT signals for infliximab as the suspected drug.The analyses suggested that the stronger positive risk signals for both drugs were focused on gastrointestinal disorders,infectious and invasive diseases,laboratory tests,musculoskeletal and connective tissue disorders,and blood,vascular,and lymphatic disorders.The risk signals for infliximab were focused on gastrointestinal disorders,infections,and infectious diseases,while the risk signals for tocilizumab were focused on the musculoskeletal muscle system.Conclusion Clinical use of both drugs in children has multi-system effects,tocilizumab may have effects on growth and development,and infliximab has effects on the gastrointestinal tract in children.

Postoperative cognitive dysfunction(POCD)is one of the common complications in the perioperative period,and it has a high incidence in elderly patients,and the large production of neuroinflammatory factors under surgical stimulation is the main cause of postoperative POCD.As an ultra-short-acting benzodiazepine of γ-aminobutyric acid receptor agonist,remimazolam can play a sedative-hypnotic and anxiolytic role in clinical practice,and can reduce inflammatory factors in the central nervous system and improve postoperative cognitive dysfunction by inhibiting neuroinflammatory response and oxidative stress.This article reviews the protective effect and mechanism of remimazolam on postoperative cognitive function,so as to provide a basis for the clinical use of remimazolam.

Based upon the underlying mechanism and pathological evidence of tissue injury of antibody-mediated rejection (AMR) , four etiological and symptomatic therapies were proposed for managing AMR, including etiological treatment of AMR including antibody-targeting, B cell or plasma cell-targeting therapies; strategies for preventing antibody-mediated endothelial damage: an inhibition of complement/antibody dependent cell-mediated pathways; anticoagulant & thrombolytic therapies for thrombotic microangiopathy secondary to endothelial damage ; anti-inflammatory therapies for acute/chronic vascular inflammation secondary to endothelial damage. Etiological treatment is essential for preventing and treating AMR while symptomatic measures, such as anticoagulant, thrombolytic and antiinflammatory therapies, are stressed. Finally the authors devised therapeutic strategies for AMR in 4 different patient groups of non-sensitized allograft recipients, sensitized allograft recipients, individuals with active AMR and those with chronic active AMR.

The paper is to establish an UPLC-MS/MS method for the simultaneous determination of 19 components in Microctis Folium from different production areas. The 50% methanol was used as extraction solvent. The Agilent ZORBAX SB C18 (150 mm × 2.1 mm, 1.8 μm) column was used; mobile phase was acetonitrile - 0.1% acetic acid with gradient elution, flow rate was 0.3 mL·min^-1, colume temperature was 30 ℃, and the injection volume was 2 μL; electrospray ionizaton source was used and detected in negative ion mode. The results showed that the established UPLC-MS/MS method could well separate the 19 components, and the methodological investigation results of 19 components were good. By means of orthogonal partial least squares discriminant analysis (OPLS-DA), 28 batches of Microctis Folium samples from different production areas can be divided into three categories, Guangdong, Guangxi and Hainan are each classified into one category, and 10 signature compounds which affecting the quality differences of different production areas were screened out. The established method is accurate, reliable, sensitive and reproducible. It can provide a basis for the establishment of the quality standard of Microctis Folium, as well as for safety and quality research.

The purpose of this study was to investigate the intervention effect and mechanism of Lycium barbarum leaves on letrozole-induced polycystic ovary syndrome (PCOS) mice. The PCOS model was prepared by letrozole combined with high-fat diet. After successful modeling, 40 mice were randomly divided into PCOS group, positive drug metformin group, low-dose Lycium barbarum leaves group, and high-dose Lycium barbarum leaves group. The corresponding drugs were given by gavage for 29 days. At the end of the experiment, the eyeballs were removed for blood collection and ovarian tissue was collected. The ovarian mass, fasting blood glucose (FBG), fasting insulin (FINS), testosterone (T), anti-Mullerian hormone (AMH), luteinizing hormone (LH), follicle stimulating hormone (FSH), and estradiol (E₂) levels were measured in each group. The morphology of ovarian tissue was observed by hematoxylin-eosin staining, and the oocytes, cystic follicles and corpus luteum were counted. Cecal contents of mice were collected for analysis of intestinal flora composition and differential flora. The animal experiment process was approved by the Animal Ethics Committee of Nanjing University of Traditional Chinese Medicine. The results showed that the estrous cycle of PCOS mice was disordered. Compared with the PCOS group, the Lycium barbarum leaves group can significantly reduce the ovarian damage of mice, reduce the number of cystic dilated follicles, and normalize the estrous cycle. After the intervention of Lycium barbarum leaves, the levels of FBG, FINS, T, AMH, LH, FSH and LH/FSH were significantly decreased (P < 0.05), while the level of E₂ was significantly increased (P < 0.001). In addition, Lycium barbarum leaves can regulate the disorder of intestinal flora diversity in PCOS mice, increase the abundance of Bacteroidetes, and reduce the abundance of Firmicutes, Ileibacterium, Romboutsia and Faecalibaculum. In summary, Lycium barbarum leaves can play a therapeutic role in PCOS mice by improving insulin resistance, regulating reproductive hormone disorders and gut microbiota imbalance. It provides scientific basis and useful reference for the rational utilization and development of Lycium barbarum leaves.