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.

This study aims to investigate the effect of salvianolic acid B (Sal B), the active ingredient of Salvia miltiorrhiza, on H9C2 cardiomyocytes injured by oxygen and glucose deprivation/reperfusion (OGD/R) through regulating mitochondrial fission and fusion. The process of myocardial ischemia-reperfusion injury was simulated by establishing OGD/R model. The cell proliferation and cytotoxicity detection kit (cell counting kit-8, CCK-8) was used to detect cell viability; the kit method was used to detect intracellular reactive oxygen species (ROS), total glutathione (t-GSH), nitric oxide (NO) content, protein expression levels of mitochondrial fission and fusion, apoptosis-related detection by Western blot. Mitochondrial permeability transition pore (MPTP) detection kit and Hoechst 33342 fluorescence was used to observe the opening level of MPTP, and molecular docking technology was used to determine the molecular target of Sal B. The results showed that relative to control group, OGD/R injury reduced cell viability, increased the content of ROS, decreased the content of t-GSH and NO. Furthermore, OGD/R injury increased the protein expression levels of dynamin-related protein 1 (Drp1), mitofusions 2 (Mfn2), Bcl-2 associated X protein (Bax) and cysteinyl aspartate specific proteinase 3 (caspase 3), and decreased the protein expression levels of Mfn1, increased MPTP opening level. Compared with the OGD/R group, it was observed that Sal B had a protective effect at concentrations ranging from 6.25 to 100 μmol·L^-1. Sal B decreased the content of ROS, increased the content of t-GSH and NO, and Western blot showed that Sal B decreased the protein expression levels of Drp1, Mfn2, Bax and caspase 3, increased the protein expression level of Mfn1, and decreased the opening level of MPTP. In summary, Sal B may inhibit the opening of MPTP, reduce cell apoptosis and reduce OGD/R damage in H9C2 cells by regulating the balance of oxidation and anti-oxidation, mitochondrial fission and fusion, thereby providing a scientific basis for the use of Sal B in the treatment of myocardial ischemia reperfusion injury.

Plant natural products have a wide range of pharmacological properties, not only can they be used as plant dietary supplements to meet the nutritional needs of the human body in the accelerated pace of life, but also occupy an important position in the research and development of therapeutic drugs for the treatment of tumors, inflammation and other diseases, and have been widely accepted by the public due to their good safety. However, despite the above advantages of plant natural products, limiting factors such as low solubility, poor stability, lack of targeting, high toxicity and side effects, and unacceptable odor have greatly impeded their conversion to clinical applications. Therefore, the development of new avenues for the application of new natural products has become an urgent problem to be solved at present. In recent years, with the continuous development of research, various strategies have been developed to improve the bioavailability of natural products. Among them, nanocarrier delivery system is one of the most attractive strategies at present. In past studies, a large number of nanomaterials (organic, inorganic, etc.) have been developed to encapsulate plant-derived natural products for their efficient delivery to specific organs and cells. Up to now, nanotechnology has not only been limited to pharmaceutical applications, but is also competing in the fields of nanofood processing technology and nanoemulsions. Among the various nanocarriers, liposomes are the largest nanocarriers with the largest market share at present. Liposomes are bilayer nanovesicles synthesized from amphiphilic substances, which have advantages such as high drug loading capacity and stability. Attractively, the flexible surface of liposomes can be modified with various functional elements. Functionalized modification of liposomes with different functional elements such as antibodies, nucleic acids, peptides, and stimuli-responsive moieties can bring out the excellent drug delivery function of liposomes to a greater extent. For example, the modification of functional elements with targeting function such as nucleic acids and antibodies on the surface of liposomes can deliver natural products to the target location and improve the bioavailability of drugs; the modification of stimulus-responsive groups such as photosensitizers, magnetic nanoparticles, pH-responsive groups, and temperature sensitizers on the surface of liposomes can achieve controlled release of drugs, localized targeting, and synergistic thermotherapy. In addition to the above properties, by using functionalized liposomes to encapsulate natural products with irritating properties can also effectively mask the irritating properties of natural products, improve public acceptance, and increase the possibility of application of irritating natural products. There are various strategies for modifying liposomes with functional elements, and the properties of functionalized liposomes constructed by different construction strategies differ. The commonly used construction strategies for functionalized liposomes include covalent modification and non-covalent modification. These two types of construction strategies have their own advantages and disadvantages. Covalent modification has better stability than non-covalent modification, but its operation is cumbersome. With the above background, this review focuses on the three typical problems faced by plant natural products at present, and summarizes the specific applications of functionalized liposomes in them. In addition, this paper summarizes the construction strategies for building different types of functionalized liposomes. Finally, this paper will also review the opportunities and challenges faced by functionalized liposomes to enter clinical therapy, and explore the opportunities to overcome these problems, with a view to better realizing the precise control of plant nanomedicines, and providing ideas and inspirations for researchers in related fields as well as relevant industrial staff.

A precursor ion selection (PIS) based ultra high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-Q-TOF-MS) analytical method was used to screen the chemical components in Jiawei Dingzhi pills (JWDZP) comprehensively and rapidly. To compile the components of the compound medicine, a total of 1 921 components were found utilizing online databases and literature. After verifying the sources, unifying the component names, merging the multi-flavor attributed components, and removing the weak polar molecules, 450 components were successfully retained. The Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 μm) was used, with a 0.1% formic acid water (A)-acetonitrile (B) as the mobile phase. The flow rate was 0.35 mL·min^-1, the column temperature was 35 ℃, and an electrospray ion source was used. Data was collected with the PIS strategy in both positive and negative ion modes. Compounds were screened through matching accurate molecular weight of the database, and identified according to MS/MS data (characteristic fragment ions and neutral loss), with comparison of reference. Some compounds were confirmed using standard products. A total of 176 compounds were screened out in the extract of JWDZP, among which 26 compounds were confirmed by standard products. These compounds include 96 components from the sovereign drug, and 34 coefflux components with low ion intensity. The PIS-UHPLC-Q-TOF-MS/MS method established in this study can quickly and comprehensively screen the chemical components of JWDZP, which enhanced the screening rate of components with co-elution compounds of low ion intensities and provided a basis for the study of the material foundation of JWDZP.

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.

Objective To observe the effect of Anchang Formula(mainly composed of Agrimoniae Herba,Sanguisorbae Radix,Poria,Pulsatillae Radix,Atractylodis Macrocephalae Rhizoma,and fried Paeoniae Radix Alba)combined with Aluminum Phosphate Gel on inflammatory factors,immune function and intestinal flora in patients with radiation enteritis caused by radiotherapy for cervical cancer.Methods Seventy-eight patients with radiation enteritis caused by radiotherapy for cervical cancer were randomly divided into combined group(41 cases)and reference group(37 cases).The reference group was treated with Aluminum Phosphate Gel,and the combined group was treated with Anchang Formula combined with Aluminum Phosphate Gel.The course of treatment for the two groups lasted for 15 days.The changes of traditional Chinese medicine(TCM)syndrome scores,serum interleukin 2(IL-2),procalcitonin(PCT),T lymphocyte subsets CD4+,CD8+,CD4+/CD8+ levels and intestinal flora in the two groups were observed before and after treatment.After treatment,the clinical efficacy of the two groups was evaluated.Results(1)After 15 days of treatment,the total effective rate of the combined group was 90.24%(37/41),and that of the reference group was 70.27%(26/37).The intergroup comparison showed that the clinical efficacy of the combined group was significantly superior to that of the reference group(P＜0.05).(2)After treatment,the scores of TCM symptoms of mucopurulent bloody stool,diarrhea,tenesmus and abdominal pain in the two groups were lower than those before treatment(P＜0.05),and the decrease in the combined group was significantly superior to that in the reference group(P＜0.01).(3)After treatment,the levels of serum inflammatory factors of IL-2 and PCT in the two groups were lower than those before treatment(P＜0.05),and the decrease in the combined group was more obvious than that in the reference group(P＜0.01).(4)After treatment,the levels of immune function indicators of T lymphocyte subsets CD4+ and CD4+/CD8+ in the two groups were higher than those before treatment(P＜0.05),and the level of CD8+ was lower than that before treatment(P＜0.05).The increase of CD4+ and CD4+/CD8+ levels and the decrease of CD8+ levels in the combined group were more obvious than those in the reference group(P＜0.01).(5)After treatment,the levels of intestinal flora of Lactobacillus,Bifidobacterium and Escherichia coli in the two groups were higher than those before treatment(P＜0.05),and the increase in the combined group was more obvious that in the reference group(P＜0.01).Conclusion Anchang Formula combined with Aluminum Phosphate Gel exerts significant efficacy for the treatment of patients with radiation enteritis caused by radiotherapy for cervical cancer.The combined therapy can effectively relieve the clinical symptoms of patients,reduce the inflammatory reaction,improve the immune function,and balance the intestinal flora.

Objective To investigate the association between auditory processing and problem behaviors in preschool children,as well as the mediating role of executive function.Methods A total of 2 342 preschool children were selected from 7 kindergartens in Nanjing,China from June to August 2021.They were evaluated using Preschool Auditory Processing Assessment Scale,Conners Parent Symptom Questionnaire,and Behavior Rating Inventory of Executive Functioning-Preschool version.Children with different demographic features were compared in the scores and the abnormality rates of auditory processing,problem behaviors,and executive function.The influencing factors of the total scores of auditory processing,problem behaviors,and executive function were evaluated using multiple linear regression analysis.Whether executive function was a mediating factor between auditory processing and executive function was examined.Results Sex and grade were the main influencing factors for the total score of auditory processing(P<0.05),and sex,grade,parental education level,and family economic status were the main influencing factors for the total scores of problem behaviors and executive function(P<0.05).The auditory processing score(rs= 0.458,P<0.05)and problem behavior score(rs=0.185,P<0.05)were significantly positively correlated with the executive function score,and the auditory processing score was significantly positively correlated with the problem behavior score(rs=0.423,P<0.05).Executive function played a partial mediating role between auditory processing and problem behaviors,and the mediating effect accounted for 33.44% of the total effect.Conclusions Auditory processing can directly affect the problem behaviors of preschool children and indirectly affect problem behaviors through executive function.[Chinese Journal of Contemporary Pediatrics,2024,26(2):174-180]

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective To investigate the effect and mechanism of andrographolide(AG)on lipopolysaccharide(LPS)-induced ferroptosis in renal tubular epithelial cells(HK-2 cells).Methods HK-2 cells were treated with LPS to simulate the in vitro HK-2 injury model of sepsis.The cells were further treated with AG of 5,10,20,40 μmol/L and randomly divided into control group,LPS group,LPS+dimethyl sulfoxide group(DMSO group),and AG group.Cell viability was detected by the CCK-8 method,and the optimal concentrations of LPS and AG were screened.Cell morphological change,the levels of kidney injury markers,including neutrophil gelatinase-associated lipocalin(NGAL),kidney injury molecule-1(KIM-1),malondialdehyde(MDA),glutathione(GSH)and reactive oxygen species(ROS),as well as the expression levels of ferroptosis regulatory proteins such as solute carrier family 7 member 11(SLC7A11),glutathione peroxidase 4(GPX4)and ferritin in each group were compared,and the pro-tective effect of AG treatment on the cells was evaluated.Results Compared with the control group,the cell viabi-lity and GSH content decreased significantly in HK-2 cells treated with 10 μg/mL LPS;cell shrinkage and adhesion ability were poor;the contents of oxidative products MDA and ROS,as well as the levels of kidney injury markers NGAL and KIM-1 increased significantly,while expression levels of SLC7A11 and GPX4 protein decreased;ferritin expression level increased;differences were all statistically significant(all P＜0.05).Compared with LPS group,the cell viability,GSH content,as well as protein expression levels of SLC7A11 and GPX4 increased significantly after AG intervention,while ferritin expression level decreased,differences were all significant(all P＜0.05).MDA content,ROS fluorescence intensity,and the levels of kidney injury markers NGAL and KIM-1 decreased sig-nificantly,difference were all significant(all P＜0.05).Conclusion AG has a protective effect on LPS-induced HK-2 cell injury,possibly by activating SLC7A11/GPX4 pathway,reducing oxidative stress,up-regulating antioxi-dant enzyme activity,and alleviating ferroptosis.

Objective To analyze the risk factors and survival status of Epstein-Barr virus(EBV)infection in pa-tients with aplastic anemia(AA)after haploid allogeneic hematopoietic stem cell transplantation(Haplo-HSCT).Methods Clinical data of 78 AA patients who underwent Haplo-HSCT in the hematology department of a hospital from January 1,2019 to October 31,2022 were analyzed retrospectively.The occurrence and onset time of EBV viremia,EBV-related diseases(EBV diseases),and post-transplant lymphoproliferative disorders(PTLD)were ob-served,risk factors and survival status were analyzed.Results Among the 78 patients,38 were males and 40 were females,with a median age of 33(9-56)years old;53 patients experienced EBV reactivation,with a total inci-dence of 67.9％,and the median time for EBV reactivation was 33(13,416)days after transplantation.Among pa-tients with EBV reactivation,49 cases(62.8％)were simple EBV viremia,2 cases(2.6％)were possible EBV di-seases,and 2 cases(2.6％)were already confirmed EBV diseases(PTLD).Univariate analysis showed that age 1＜40 years old at the time of transplantation,umbilical cord blood infusion,occurrence of acute graft-versus-host disease(aGVHD)after transplantation,and concurrent cytomegalovirus(CMV)infection were independent risk fac-tors for EBV reactivation in AA patients after Haplo-HSCT.Multivariate analysis showed that concurrent CMV in-fection was an independent risk factor for EBV reactivation in A A patients after Haplo-HSCT(P=0.048).Ritu-ximab intervention before stem cell reinfusion was a factor affecting the duration of EBV reactivation(P＜0.05).The mortality of EBV viremia,EBV diseases,and PTLD alone were 8.2％,50.0％,and 100％,respectively.The 2-year overall survival rate of patients with and without EBV reactivation were 85.3％,and 90.7％,respectively,difference was not statistically significant(P=0.897).However,patients treated with rituximab had 2-year lower survival rate than those who did not use it,with a statistically significant difference(P=0.046).Conclusion EBV reactivation is one of the serious complications in AA patients after Haplo-HSCT,which affects the prognosis and survival of patients.