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.

Methamphetamine abuse is a major public health problem in the world,and in recent years,methamphetamine is also the most abused synthetic drug in China.The neurotoxic or addiction mechanism of methamphetamine has not been fully clarified,and there is still a lack of specific withdrawal methods and drugs for methamphetamine abuse.Mitochondria are not on-ly the organelles to which methamphetamine directly produces toxic effects,but also participate in regulating the neurotoxic damage process of methamphetamine.Mitochondrial quality is the regulatory basis for maintaining mitochondrial homeostasis and is regulated by three main mechanisms,which are mitochon-drial biogenesis,mitochondrial dynamic,and mitophagy.This review summarizes the research progress of mitochondrial quality control in methamphetamine-induced neurotoxicity,which may provide theoretical support for further research on the mechanism of methamphetamine neurotoxicity and development the mito-chondria-targeting drugs.

Modern Chinese medicine studies have confirmed that the interaction between traditional Chinese medicine(TCM)and intestinal flora is the key to the treatment of diseases with tradi-tional Chinese medicine.This interplay includes such activities as:traditional Chinese medicine can be metabolized by intestinal flora into effective components with different biological activities from its precursors;TCM chemicals improve the composition of gut microbiota,consequently ameliorating its dysfunction as well as associated pathological conditions;and gut microbiota mediate the interactions between the multiple chemicals in TCM.There-fore,it becomes an important way to understand the modern sci-entific connotation of traditional Chinese medicine theory to study the pharmacological mechanism of the efficacy of traditional Chi-nese medicine by targeting Gut microbiota.

Objective To explore characteristics of clinical and imaging findings in patients with fat embolism syndrome.Methods From January 2021 to October 2022,clinical manifestations of 13 patients with fat embolism due to fracture or or-thopaedic surgery were retrospectively analyzed,including 11 males and 2 females,aged from 17 to 60 years old.Mental and respiratory abnormalities and changes in vital signs occurred after admission or after surgery,and patient's chest and brain imaging results were abnormal.The patient's mental and respiratory abnormalities,vital signs,chest and brain imaging results were continuously monitored.Results The main clinical manifestations of fat embolism syndrome were abnormal pulmonary respiration in 13 patients,abnormal central nervous function in 7 patients,and spotted rash in 2 patients.Chest CT showed dif-fuse distribution of ground glass shadows in 13 patients,and severe symptoms were"snowstorm".Nine patients with ground glass fusion consolidation,5 patients with multiple nodules and 4 patients accompanied by bilateral pleural effusion.Head CT findings of 5 patients were negative,and head MRI findings of 1 patient showed multiple T1WI low signal,T2WI high signal shadow,DWI high signal shadow,and"starry sky sign"in basal ganglia,radiative crown,hemioval center,thalamus,frontal parietal cortex and subcortex.Conclusion Fat embolism syndrome has a high mortality rate.Clinical manifestations of respira-tory system and nervous system are not specific,and the skin spot rash has a characteristic manifestation.The"blizzard"sign is the specific manifestation of chest X-ray and CT examination of fat embolism,and the"starry sky"sign is the typical manifesta-tion of diffusion-weighted sequence of brain MRI examination of fat embolism.

Objective With the widespread of transcatheter aortic valve replacement(TAVR)in patients with severe symptomatic aortic stenosis(AS),the life-cycle management has become a major determinant of prognosis.Methods A total of 408 AS patients who underwent successfully TAVR from June 2021 to August 2023 were consecutively enrolled in Hospital Valve Intervention Center.Patients were assigned to the Usual Care(UC)group between June 2021 and October 2022,while patients were assigned to the Heart Multi-parameter Monitoring(HMM)group between November 2022 and August 2023.The primary endpoint was defined as composite endpoint within 6 months post-TAVR,including all-cause death,cardiovascular death,stroke/transient ischemic attack,conduction block,myocardial infarction,heart failure rehospitalization,and major bleeding events.Secondary endpoints were the time interval(in hours)from event occurrence to medical consultation or advice and patient satisfaction.Statistical analysis was performed using Kaplan-Meier and multivariable Cox proportional hazards models.Results The incidence of primary endpoint in HMM group was significantly lower than that in UC group(8.9％vs.17.7％,P=0.016),the driving event was the rate of diagnosis and recognition of conduction block.The average time intervals from event occurrence to receiving medical advice were 3.02 h in HHM group vs.97.09 h in UC group(P＜0.001).Using cardiac monitoring devices and smart healthcare platforms provided significant improving in patients long-term management(HR 0.439,95％CI 0.244-0.790,P=0.006).Conclusions The utilization of cardiac monitoring devices and smart healthcare platforms effectively alerted clinical events and improved postoperative quality of life during long-term management post TAVR.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Chlamydia psittaci is a worldwide distributed zoonotic pathogen that infects a variety of birds.In order to char-acterization of the duck originated C.psittaci strains,lung samples were collected from suspected infection ducks and was de-tected by real-time PCR.The positive samples were homogenized in phosphate buffered saline with kanamycin and streptomy-cin,and then inoculated onto L929 cells monolayer.After several sets of passages,chlamydial inclusions of the isolate in cul-tured cells were observed after Giemsa staining or by electron microscope.For species identification,16S rRNA,16-23S IGS gene fragments were sequenced and analyzed.Genotyping of the isolate was performed by comparative analysis of the obtained ompA gene sequence with that of different genotype of C.psittaci strains.A C.psittaci strain was successfully isolated from the lung sample of duck by cell culture and was identified as genotype A.This study expanded our understanding of the host range of genotype A C.psittaci strain,and provided basis for further research on the pathogenicity,transmission,and public health risk of this pathogen.

Objective:This study aims to evaluate the clinical efficacy and safety of Dibai Yijing Formula(DYF)in the treat-ment of male infertility with essence deficiency in the kidney and damp-heat in the essence chamber(Abbreviation:kidney deficiency and damp-heat type).Methods:This study employed a randomized,controlled clinical trial design,recruiting 72 male patients with infertility due to kidney deficiency and damp-heat type.Patients were randomly assigned to an treatment group(36 patients)and a control group(36 patients)using a random number table.The control group received oral Clomiphene Citrate Capsules(50 mg,twice daily),while the treatment group received oral DYF(one dose daily,200 ml each time,30 minutes after breakfast and dinner).Both groups underwent a 12-week treatment period.After treatment,sperm concentration(SC),percentage of progressively motile sperms(PR),total sperm motility[PR+percentage of non-progressively motile sperms(NP)],and semen volume(SV)were compared between the two groups before and after treatment.Additionally,the total score of Traditional Chinese Medicine(TCM)syndrome score and sperm DNA fragmentation index(DFI)and pregnancy outcomes of the patients'spouses were compared between the two groups.Results:Three patients dropped out from the treatment group and four from the control group.There were no statistically sig-nificant differences in semen parameters between the two groups(P＞0.05).After treatment,the patients in the treatment group showed significant difference in the percentage of SC([19.42±5.30]x 106/ml vs[10.75±2.41]x 106/ml),PR([27.72±6.62]％vs[20.04±4.10]％),PR+NP([49.86±10.68]％vs(33.74±5.58)％],DFI([12.33±3.43]％vs[15.06±3.98]％)and TCM symtom score([7.45±1.82]vs[13.85±1.91]),and the difference was statistically significant(P＜0.05).The patients in the control group showed significant difference in the percentage of SC([19.56±5.24]× 106/ml vs[11.31±2.08]× 106/ml)and TCM symptom score([12.81±1.86]vs[14.06±1.64]).But no significant changes were observed in the PR([21.75±5.93]％vs[20.05±4.67]％),PR+NP([34.23±7.15]％vs[32.35±4.09]％),SV([3.19±1.08]ml vs[3.12±1.13]ml),and DFI([15.11±4.76]％vs[15.51±4.35]％)were not statistically significant(P＞0.05).Improve-ments in PR,PR+NP,TCM symptom score and DFI in the treatment group were better than those in the control group after treatment(P＜0.05);the differences in SC and SV and spousal pregnancy in the treatment group were not statistically significant compared with those in the control group(P＞0.05).No serious adverse events occurred in both groups during the treatment period.Conclusion:The treatment of male infertility with DYF is effective and safe.

AIM To investigate the clinical effects of Buyang Huanwu Decoction combined with Erlong Xizhu Acupuncture Method on elderly patients with stroke.METHODS Ninety-six patients were randomly assigned into control group(48 cases)for 1-month intervention of Erlong Xizhu Acupuncture Method,and observation group(48 cases)for 1-month intervention of both Buyang Huanwu Decoction and Erlong Xizhu Acupuncture Method.The changes in neurological function indices(NIHSS score,NDS score),Hcy,CysC,vascular endothelial function indices(ET-1,NO,vWF),intracranial hemodynamic indices(Vmean,R,DR),hemorheological indices(WBLSV,WBHSV,FIB,HCT,EAI)and prognosis assessment indices(mRS score,BI score)were detected.RESULTS After the treatment,the two groups displayed decreased neurological function indices,Hcy,CysC,ET-1,vWF,R,DR,hemorheological indices,mRS score(P＜0.05),and increased NO,Vmean,BI score(P＜0.05),especially for the observation group(P＜0.05).CONCLUSION For the elderly patients with stroke,Buyang Huanwu Decoction combined with Erlong Xizhu Acupuncture Method can reduce serum Hcy,CysC levels,and improve vascular endothelial functions,intracranial hemodynamics,hemorheological indices,thus improve neurological functions and promote prognosis.

Objective:To compare the efficacy between vonoprazan fumarate and rabeprazole for the treatment of artificial ulcers after endoscopic submucosal dissection (ESD).Methods:In this prospective randomized controlled study, patients who underwent ESD between December 2021 and August 2023 at Jiangsu Province Hospital were enrolled and randomly divided into two groups. Vonoprazan fumarate combined with rebamipide (vonoprazan group) or rabeprazole combined with rebamipide (rabeprazole group) were given respectively from the 4th day after ESD. After 8 weeks, the healing of the ulcers was compared.Results:Ninety-one patients were enrolled in the study, including 51 in the vonoprazan group and 40 in the rabeprazole group. The ulcer area reduction rate of the vonoprazan group was significantly higher than that of the rabeprazole group (92.86%±3.80% VS 90.04%±4.28%, t=3.281, P=0.001), but there was no significant difference in the healing rate [15.69% (8/51) VS 7.50% (3/40), χ2=1.414, P=0.234] or the adverse event occurrence ( P>0.05) between the two groups. Conclusion:Vonoprazan fumarate can achieve better ulcer treatment without increasing the risk of adverse events.