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 develop a matrix metalloproteinase(MMP)-responsive hyaluronic acid(HA)-based controlled-release material for brain-derived neurotrophic factor(BDNF)to provide a novel therapeutic strategy for intervention and repair of traumatic brain injury(TBI).Methods HA was modified with amination,followed by condensation with Suflo-SMCC carboxyl group to form amide,and then linked with glutathione(GSH)to synthesize HA-GSH.The recombinant glutathione S-transferase(GST)-tissue inhibitor of metalloproteinase(TIMP)-BDNF(GST-TIMP-BDNF)expression plasmid was constructed using molecular cloning technique with double enzyme digestion by Bam H Ⅰ and Eco R Ⅰ.The recombinant GST-TIMP-BDNF protein was expressed in the Escherichia coli prokaryotic expression system,and purified by ion exchange chromatography,confirmed by Western blotting.MMP diluents were supplemented with PBS,MMP inhibitor marimastat,and varing concentrations(0.4,0.6,0.8 mg/ml)of GST-TIMP-BDNF or GST-BDNF.MMP-2 activity was analyzed using an MMP activity detection kit to evaluate the inhibitory effect of the recombinant protein on MMP.Primary rat neurons were extracted and cultured to establish an iron death model induced by RSL3.The effect of recombinant protein GST-TIMP-BDNF on neuronal injury was detected by immunofluorescence staining.Results MRI hydrogen spectrum identification confirmed the successful synthesis of HA-GSH.Western blotting results showed the successful expression of the recombinant protein GST-TIMP-BDNF containing the GST tag using the E.coli prokaryotic expression system.MMP activity detection results indicated that the recombinant protein GST-TIMP-BDNF had a superior inhibitory effect on MMP-2 activity compared to GST-BDNF(P<0.05).Immunofluorescence staining results showed a significant increase in fluorescence intensity in rat neurons treated with GST-TIMP-BDNF after RSL3 induction(P<0.05).Conclusion A MMP-responsive HA-based BDNF controlled-release material has been successfully developed,exhibiting a protective effect on neuron damage.

Aim To investigate the effect of vanillin on the regulation of cyclic guanylate adenylate synthetase(cGAS)/stimulator of interferon gene(STING)signa-ling pathway on hepatic tissue injury in rats with intra-hepatic cholestasis(IC).Methods SD rats were randomly divided into normal group,IC group,vanillin group,cGAS overexpression group,and vanillin+cGAS overexpression group,with continuous adminis-tration for seven days.The body weight,liver weight and liver to body weight ratio of rats were measured.Liver function(ALT,AST,ALP,LDH),IC(TBIL,TBA)and liver fibrosis(HA,LN,PC Ⅲ)index were determined by ELISA.Liver pathology and fibrosis were observed using HE and Masson staining,and col-lagen volume fraction was calculated.The expression of cGAS/STING pathway related proteins in liver tissue was detected by Western blot.Results Vanillin could improve liver pathology and fibrosis,increase body weight,and decrease liver weight,ALT,AST,ALP,LDH,TBIL,TBA,HA,LN,PC Ⅲ,collagen volume fraction,cGAS,STING protein in IC rats(P＜0.05).Overexpression of cGAS could reverse the effects of vanillin on the above indicators in IC rats(P＜0.05).Conclusions Vanillin may improve liver function,IC,liver fibrosis,and liver tissue damage in IC rats by downregulating the cGAS/STING signaling pathway.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective To explore association between childhood trauma,resilience and non-suicidal self-injury in adolescents.Methods One hundred and fifty-eight first-episode adolescent patients with mood disorders were selected and divided into NSSI group(n=94)and non-NSSI group(n=64)based on presence or absence of NSSI.The Hamilton depression scale(HAMD),Hamilton anxiety scale(HAMA),childhood trauma questionnaire(CTQ-SF)and Connor-Davidson resilience scale(CD-RISC)were used to evaluate the depression and anxiety symptoms,childhood trauma and resilience.Results There were more cases of younger age(16.17±1.67 vs.16.73±1.37),lower education level(30.9% vs.15.6% ),left behind experience(48.9% vs.29.7% ),school bullying(46.8% vs.25.0% ),suicide ideation(85.1% vs.37.5% )and history of attempted suicide(29.8% vs.6.3% )in the group with NSSI compared to those without NSSI.The HAMD score(27.99±5.94 vs.24.19±5.19),HAMA score(18.02±5.94 vs.15.45±4.99),CTQ total score(48.43±15.40 vs.41.97±9.75),emotional abuse score(12.77±6.06 vs.10.19±4.06),and emotional neglect score(11.40±5.34 vs.9.14±3.55)were higher in the group with NSSI,and the differences between the two groups were significant(P<0.05).The total scores of psychological resilience(39.83±10.27 vs.28.66±12.75),resilience(19.59±4.92 vs.12.28±6.47),strength(12.03±3.98 vs.9.99±4.67),and optimism(8.98±2.97 vs.6.47±3.73)in the group without NSSI were higher than those in the group with NSSI(P<0.05).Logistic regression analysis showed that left behind experience(OR=4.494,95% CI:1.192-16.940),school bullying(OR=5.983,95% CI:1.329-26.945),suicidal ideation(OR=13.225,95% CI:2.908-60.146),history of attempted suicide(OR=16.769,95% CI:1.845-152.379),HAMD(OR=1.264,95% CI:1.046-1.626),emotional abuse(OR=1.327,95% CI:1.093-1.612),and resilience(OR=0.468,95% CI:0.266-0.823)were significantly associated with adolescent mood disorders with NSSI(P<0.05).Conclusion Left behind experience,campus bullying,suicidal ideation and attempted suicide,emotional abuse,degree of depression,and psychological resilience may be associated with NSSI behavior in adolescents with mood disorders.

Objective To observe whether the IL-23/Th17 inflammatory pathway is involved in the development of calcific aortic valve disease,and whether secukinumab can delay the progression of calcific aortic valve disease by inhibiting this pathway.Methods Forty-seven mice were divided into a blank control group,model group,and secukinumab group according to the random number table method.The blank control group was fed normal chow,while the model group and secukinumab group were fed pro-calcification chow for 16 weeks to establish a calcific aortic valve disease model.After intervention with secukinumab for 4 weeks,peak flow velocity changes in the aortic valves were detected under Doppler ultrasonography in all mice.Relevant indexes were determined by hematoxylin and eosin staining,Von Kossa staining,immunohistochemical staining,ELISA,and qPCR.Results Compared with the model group,the secukinumab group showed significantly reduced peak flow velocity(P＜0.05)and serum IL-6,IL-17,and IL-23 levels(P＜0.05)in the aortic valve.Compared with the secukinumab group,the model group's leaflet thickness was significantly increased,and there were more calcium deposits.Immunohistochemical result showed that macrophage infiltration(P＜0.05),IL-17A(P＜0.05)and IL-23(P＞0.05)levels in the valve leaflets were reduced in the secukinumab group compared with the model group.PCR result suggested that the expression of STAT3,BMP-2,and α-SMA mRNA was significantly lower in the secukinumab group than the model group(P＜0.05).Conclusions The IL-23/Th17 inflammatory pathway is involved in the pathogenesis of calcific aortic valve disease.The inflammation,fibrosis,osteogenic differentiation,and calcification of mouse valves were alleviated after intervention with secukinumab,which may delay disease progression by inhibiting the IL-23/Th17 inflammatory pathway.

Objective:To compare the effects of unilateral thoracic paravertebal block with lidocaine on hemodynamic and the level of consciousness during double lumen endotracheal intubation.Methods:From June to october 2021,a total of 40 patients American Society of Anesthesiologists(ASA)physical status Ⅰ-Ⅱ,aged 19-65 years,scheduled for elective thoracic sugeries in Peking University Interna-tional Hospital block with under general anesthesia requiring orotracheal intubation were recruited and di-vided into two groups:The double-lumen endobronchial intubation(group C)and double-lumen endo-bronchial intubation after thoracic paravertebal block with lidocaine(group P).After an intravenous an-esthetic induction,the orotracheal double-lumen intubation was performed using a Macintosh direct laryn-goscopy,respectively.Invasive blood pressure(BP)and heart rate(HR)were recorded before and after anesthetic induction,immediately after intubation and 5 min after intubation with 1-minute interval and the intubation time was also noted.Rate-pressure product(RPP)were calculated.Results:After anes-thetic induction,BP and RPP in the two groups decreased significantly compared with their preinduction values.As comparison with their postinduction values,the orotracheal intubation in the two groups caused significant increases in BP,HR and RPP.Diastolic blood pressure(DBP)and mean arterial pressure(MAP)increased significantly and lasted for 1-minute in group C compared with the baseline values.Systolic blood pressure(SBP)was not significant change and DBP increased significantly immediately af-ter intubation in group P.HR of both groups after intubation were significantly higher than their baseline values and lasted for 4 min in group C,HR increased significantly immediately after intubation in group P.SBP,DBP,MAP,HR and RPP after intubation in group P were significantly lower than those of group C during the observation period.The value of BIS was similar between the two groups.Compared with group C,the incidence of SBP greater than 30％and RPP greater than 22 000 was significantly lower in group P in the observation period,and no patient in group P developed RPP greater than 22 000.At the end of the incidence of SBP less than 30％of the basal value and HR less than 30％of the baseline,no severe bradycardia occurred in both groups.Conclusion:During double-lumen endobronchial intubation,unilateral thoracic paravertebal block with lidocaine can provide less hemodynamic response and level of conscionsness.

In 2009,the World Health Organization included snakebite on the list of neglected tropical diseases,acknowledging it as a common occupational hazard for farmers,plantation workers,and others,causing tens of thousands of deaths and chronic physical disabilities every year.This guideline aims to provide practical information to help clinical professionals evaluate and treat snakebite victims.These recommendations are based on clinical experience and clinical research evidence.This guideline focuses on the following topics:snake venom,clinical manifestations,auxiliary examination,diagnosis,treatments,and prevention.

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.

Objective To evaluate the bioequivalence and safety of ezetimibe tablets in healthy Chinese subjects.Methods The study was designed as a single-center,randomized,open-label,two-period,two-way crossover,single-dose trail.Subjects who met the enrollment criteria were randomized into fasting administration group and postprandial administration group and received a single oral dose of 10 mg of the subject presparation of ezetimibe tablets or the reference presparation per cycle.The blood concentrations of ezetimibe and ezetimibe-glucuronide conjugate were measured by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),and the bioequivalence of the 2 preparations was evaluated using the WinNonlin 7.0 software.Pharmacokinetic parameters were calculated to evaluate the bioequivalence of the 2 preparations.The occurrence of all adverse events was also recorded to evaluate the safety.Results The main pharmacokinetic parameters of total ezetimibe in the plasma of the test and the reference after a single fasted administration:Cmax were(118.79±35.30)and(180.79±51.78)nmol·mL-1;tmax were 1.40 and 1.04 h;t1/2 were(15.33±5.57)and(17.38±7.24)h;AUC0-t were(1 523.90±371.21)and(1 690.99±553.40)nmol·mL-1·h;AUC0-∞ were(1 608.70±441.28),(1 807.15±630.00)nmol·mL-1·h.The main pharmacokinetic parameters of total ezetimibe in plasma of test and reference after a single meal:Cmax were(269.18±82.94)and(273.93±87.78)nmol·mL-1;Tmax were 1.15 and 1.08 h;t1/2 were(22.53±16.33)and(16.02±5.84)h;AUC0_twere(1 463.37±366.03),(1 263.96±271.01)nmol·mL-1·h;AUC0-∞ were(1 639.01±466.53),(1 349.97±281.39)nmol·mL-1·h.The main pharmacokinetic parameters Cmax,AUC0-tand AUC0-∞ of the two preparations were analyzed by variance analysis after logarithmic transformation.In the fasting administration group,the 90％CI of the log-transformed geometric mean ratios were within the bioequivalent range for the remaining parameters in the fasting dosing group,except for the Cmax of ezetimibe and total ezetimibe,which were below the lower bioequivalent range.The Cmax of ezetimibe,ezetimibe-glucuronide,and total ezetimibe in the postprandial dosing group was within the equivalence range,and the 90％CI of the remaining parameters were not within the equivalence range for bioequivalence.Conclusion This test can not determine whether the test preparation and the reference preparation of ezetimibe tablets have bioequivalence,and further clinical trials are needed to verify it.