BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

Objective:To explore the mechanism of Danxing Zhishuang Prescription in the treatment of Parkinson's disease (PD) by combining network pharmacology with animal models.Methods:TCMSP, BATMAN database, Genecards, and OMIM databases were retrieved to obtain the active components and action targets of Danxing Zhishuang Prescription. Venny 2.1.0 was used to intersect drug targets and PD related genes, and a protein interaction network of the intersection targets was constructed using the STRING 12.0 platform. Topology analysis was performed using Cytoscape 3.10.0 software to identify the key targets of Danxing Zhishuang Prescription on PD; GO functional and KEGG pathway enrichment analysis was performed on key targets using the WeChat platform, and molecular docking was validated through AutoDockTools 1.5.7. Using a random number table method, mice were divided into a blank control group, a model group, and a Danxing Zhishuang Prescription group, with 20 mice in each group; except for the blank group, all other groups of mice were orally administered fisetin to prepare PD models; Danxing Zhishuang Prescription group was orally administered with concentrated Danxing Zhishuang Prescription at a dosage of 10.5 g/kg, while the blank group and model group were orally administered with 0.2 ml of physiological saline for 21 days; Western blot was used to detect the expressions of Akt1, Bcl-2, Bax, and α-Syn proteins.Results:359 intersection targets, 69 core targets, and 185 active components were obtained the treatment of PD with Danxing Zhishuang Prescription. The main active components included quercetin, kaempferol, phenylalanine, etc., and the key targets were AKT1, TP53, TNF, ESR1, etc. KEGG analysis revealed several key signaling pathways, such as AGE-RAGE, PI3K-Akt, fluid shear stress and atherosclerosis signaling pathways. The validation experiment results showed that compared with the model group, the expression of Bcl-2 protein was up-regulated ( P<0.01), and the expressions of Bax, Akt1, and α-Syn proteins were down-regulated in the Danxing Zhishuang Prescription group ( P<0.01). Conclusions:Danxing Zhishuang Prescription has the advantages of multi target and multi pathway treatment for PD. Its mechanism may be related to down-regulating the expressions of Bax, Akt1, and α-Syn proteins, improving brain blood supply, regulating neurotransmitter balance, inhibiting oxidative stress response, and promoting nerve regeneration.

Objective To explore the role of forkhead box protein p2(FOXP2)in the proliferation and metastasis of uterine fibroid cells by regulating glycolysis mediated by Hedgehog signaling pathway.Methods Fresh hysteromyoma tissue was obtained from 10 patients who underwent myomectomy in the Department of Gynecology of Guizhou Provincial Hospital of Workers,and hysteromyoma cells were digested and separated.Cells were transfected with lentivirus shRNA targeting FOXP2(sh-FOXP2),negative control(sh-NC)and FOXP2 overexpression vectors(oe-FOXP2),and negative control(oe-NC).Colony formation test and Transwell assay were used to evaluate the cell proliferation and metastasis ability.Glucose uptake,lactic acid production and extracellular acidification rate(ECAR)were measured to detect the aerobic glycolysis ability of cells.A xenograft tumor model was established by up-regulating uterine leiomyoma cells with FOXP2 to explore the regulatory effect of FOXP2 in vivo.Results Compared with oe-NC group,the cell viability,colony number,migrating cell number,glucose uptake,lactic acid production and ECAR in oe-FOXP2 group decreased significantly(P＜0.05).Compared with sh-NC group,the cell viability,colony number,migrating cell number,glucose uptake,lactic acid production and ECAR of uterine fibroids in sh-FOXP2#1 and sh-FOXP2#2 groups increased significantly(P＜0.05).Compared with oe-NC+vector group,the number of colonies,migrating cells,glucose uptake,lactic acid production,ECAR,Shh and Gli proteins in oe-FOXP2+vector group decreased significantly(P＜0.05).Compared with oe-FOXP2+vector group,the number of colonies,migrating cells,glucose uptake,lactic acid production,ECAR,Shh and Gli proteins in oe-FOXP2+SAG group were significantly increased(P＜0.05).Compared with oe-NC group,the tumor weight,the proportion of Ki-67 positive cells and the proteins of Shh,Gli,GLUT1 and PGAM1 in oe-FOXP2 group decreased significantly(P＜0.05).Compared with oe-FOXP2 group,the tumor weight,the proportion of Ki-67 positive cells and the proteins of Shh,Gli,GLUT1 and PGAM1 in oe-FOXP2+SAG group increased significantly(P＜0.05).Conclusions FOXP2 participates in the proliferation and metastasis of uterine leiomyoma cells by regulating glycolysis mediated by Hedgehog signaling pathway.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.

Theory and technology of Medical Immunology are widely used in scientific research.Our teaching and research group uses experimental teaching of Medical Immunology as a platform to carry out practice of scientific research project-based experi-mental system among"5+3"integration students.By completing a mini-project research including experimental design-experimental operation-research article writing,students cultivated scientific research thinking and exercised scientific research practice ability,and generally reported that the course is very difficult,but after completing it,it is very rewarding.

Objective To explore the role of forkhead box protein p2(FOXP2)in the proliferation and metastasis of uterine fibroid cells by regulating glycolysis mediated by Hedgehog signaling pathway.Methods Fresh hysteromyoma tissue was obtained from 10 patients who underwent myomectomy in the Department of Gynecology of Guizhou Provincial Hospital of Workers,and hysteromyoma cells were digested and separated.Cells were transfected with lentivirus shRNA targeting FOXP2(sh-FOXP2),negative control(sh-NC)and FOXP2 overexpression vectors(oe-FOXP2),and negative control(oe-NC).Colony formation test and Transwell assay were used to evaluate the cell proliferation and metastasis ability.Glucose uptake,lactic acid production and extracellular acidification rate(ECAR)were measured to detect the aerobic glycolysis ability of cells.A xenograft tumor model was established by up-regulating uterine leiomyoma cells with FOXP2 to explore the regulatory effect of FOXP2 in vivo.Results Compared with oe-NC group,the cell viability,colony number,migrating cell number,glucose uptake,lactic acid production and ECAR in oe-FOXP2 group decreased significantly(P＜0.05).Compared with sh-NC group,the cell viability,colony number,migrating cell number,glucose uptake,lactic acid production and ECAR of uterine fibroids in sh-FOXP2#1 and sh-FOXP2#2 groups increased significantly(P＜0.05).Compared with oe-NC+vector group,the number of colonies,migrating cells,glucose uptake,lactic acid production,ECAR,Shh and Gli proteins in oe-FOXP2+vector group decreased significantly(P＜0.05).Compared with oe-FOXP2+vector group,the number of colonies,migrating cells,glucose uptake,lactic acid production,ECAR,Shh and Gli proteins in oe-FOXP2+SAG group were significantly increased(P＜0.05).Compared with oe-NC group,the tumor weight,the proportion of Ki-67 positive cells and the proteins of Shh,Gli,GLUT1 and PGAM1 in oe-FOXP2 group decreased significantly(P＜0.05).Compared with oe-FOXP2 group,the tumor weight,the proportion of Ki-67 positive cells and the proteins of Shh,Gli,GLUT1 and PGAM1 in oe-FOXP2+SAG group increased significantly(P＜0.05).Conclusions FOXP2 participates in the proliferation and metastasis of uterine leiomyoma cells by regulating glycolysis mediated by Hedgehog signaling pathway.