In current clinical practice, various dermal templates and skin substitutes are used to enhance wound healing. However, the role of wound commensal microbiome in regulating scaffold performance and the healing process remains unclear. In this study, we investigated the influence of both natural and synthetic scaffolds on the wound commensal microbiome and wound repair in three distinct models including diabetic wounds, burn injuries, and germ-free (GF) wounds. Remarkably, synthetic electrospun polycaprolactone (PCL) scaffolds were observed to positively promote microbiome diversity, leading to enhanced diabetic wound healing compared to the natural scaffolds Integra® (INT) and MatriDerm® (MAD). In contrast, both natural and synthetic scaffolds exhibited comparable effects on the diversity of the microbiome and the healing of burn injuries. In GF wounds with no detectable microorganisms, a reversed healing rate was noted showing natural scaffold (MAD) accelerated wound repair compared to the open or the synthetic scaffold (PCL) treatment. Furthermore, the response of the wound commensal microbiome to PCL scaffolds appears pivotal in promoting anti-inflammatory factors during diabetic wound healing. Our results emphasize that the wound commensal microbiome, mediated by different scaffolds plays an important role in the wound healing process.

BACKGROUND:In clinical application,simple interspinous fixation without additional interbody fusion has similar fixation effects to pedicle screw and rod fusion internal fixation,and can effectively reduce the range of motion of the responsible segment and the stress of the articular process.However,after simple placement of the new interspinous fusion fixation device BacFuse,the stress at the root of the spinous process is relatively concentrated,and the spinous fracture is prone to occur.If an intervertebral fusion cage is inserted in conjunction with interspinous fixation,Von Mises stress can theoretically be dispersed to reduce the risk of spinous fracture.However,there are few studies on biomechanics and finite element analysis. OBJECTIVE:To observe the biomechanical stability of interspinous fixation-assisted endoscopic interbody fusion in the treatment of severe lumbar spinal stenosis. METHODS:The normal finite element model M0 of the L4-L5 segment of the lumbar spine was established by Mimics,Geomagic,Solidworks,and ANSYS software based on the lumbar CT images of a 26-year-old adult male volunteer excluding spinal diseases.On the basis of M0,the immediate model M1 after endoscopic decompression combined with interbody fusion,the interspinous fixation device(BacFuse)model M2 after endoscopic decompression,and the interspinous fixation(BacFuse)model M3 after endoscopic-assisted interbody fusion were established.The same stress was applied to the upper surface of the L4 vertebral body in the four groups,and the lower surface of the L5 vertebral body was fixed and supported.The range of motion and the extreme Von Mises stress of the endplate bone and the posterior ligament complex of the vertebral body were analyzed under six working conditions of flexion,extension,left/right bending,and left/right rotation. RESULTS AND CONCLUSION:(1)Compared with model M0,the range of motion value of model M1 increased significantly under six working conditions.Model M2 and model M3 had a significant reduction in range of motion.(2)Compared with model M0,the maximum stress of the vertebral body in model M1 did not change significantly under the six working conditions.The maximum stress at the rear of the M2 vertebral body increased significantly.(3)Compared with model M1,the maximum stress of model M3 did not change significantly under the six working conditions.Compared with model M2,the maximum stress of model M3 decreased significantly.(4)Compared with the model M0,the extreme Von Mises stress of the L4 and L5 endplates of the model M1 was significantly increased.The extreme Von Mises stress in L4 and L5 endplates of models M2 and M3 decreased slightly.Compared with model M1,the Von Mises stress of the bone under the L4 and L5 endplate of models M2 and M3 was significantly reduced.(5)It is concluded that the implantation of BacFuse can effectively reduce the bone stress under the endplate during simple interbody fusion,decrease the risk of cage subsidence,diminish the risk of facet joint fracture on the decompression side,and provide a good stable environment for interbody fusion.The placement of an intervertebral fusion cage can reduce the stress of the root of the spinous process,which is beneficial to decrease the risk of fracture of the root of the spinous process.

Objective To explore the effect and possible mechanism of aerobic exercise and empagliflozin(EMPA)on isoproterenol(ISO)-induced pathological cardiac remodeling.Methods Mice were divided randomly into control(Con),ISO,exercise(EX)+ISO,EMPA+ISO,and EX+EMPA+ISO groups.Mice in the EX groups were trained continuously for 6 weeks,mice in the EMPA groups were gavaged continuously for 4 weeks,and mice in the ISO groups were injected subcutaneously with ISO for 7 days before dissection.After euthanasia,the whole heart mass index,left heart mass index,heart mass to tibial length ratio,and left heart mass to tibial length ratio were calculated by weighing and measuring.Pathological changes,collagen fiber deposition,and myocardial cell cross-sectional area in the hearts were detected by hematoxylin and eosin,Sirius red,and wheat germ agglutinin staining.The expression levels of genes and proteins related to cardiac fibrosis and hypertrophy,macrophage infiltration,ferroptosis,and the phosphoinositide 3-kinase(PI3K)/AKT pathway were examined by quantitative reverse transcription-polymerase chain reaction,Western Blot,and immunofluorescence staining.Results(1)The whole heart mass index,left heart mass index,heart mass to tibial length ratio,and left heart mass to tibial length ratio showed downward trends in the EX+ISO group compared with the ISO group.The whole heart mass index and left heart mass index were significantly decreased in the EMPA+ISO group(P＜0.01,P＜0.05),and the heart mass to tibial length ratio and left heart mass to tibial length ratio were both down regulated.Mice in the EX+EMPA+ISO group had a significant decrease in whole heart mass index(P＜0.05),and the other three indicators were all down-regulated.(2)Myocardial cells were more orderly in the three intervention groups compared with the ISO group,with significant reductions in inflammatory cell infiltration(P＜0.01),the area of cardiac fibrosis,and the cross-sectional area of myocardial cells(P＜0.001).(3)The mRNA and protein expression levels of Col 1 and Anp were significantly reduced in the three intervention groups compared with the ISO group(P＜0.05,P＜0.01,P＜0.001).Col 3 mRNA expression significantly reduced in the EMPA+ISO and EX+EMPA+ISO groups(P＜0.05),and showed a downward trend in the EX+ISO group.(4)Macrophage infiltration and IL-6 mRNA levels were significantly reduced in the three intervention groups compared with the ISO group(P＜0.05,P＜0.01,P＜0.001).(5)Nrf2 and Gpx4 mRNA levels were upregulated in the three intervention groups compared with the ISO group,with a significant increase in GPX4 protein expression(P＜0.01,P＜0.001)and a significant decrease in HO-1 protein expression(P＜0.01,P＜0.001).(6)Pi3k mRNA levels were significantly increased in the EX+ISO group compared with the ISO group(P＜0.05),and Pi3k mRNA was upregulated in the EMPA+ISO and EX+EMPA+ISO groups.Akt mRNA levels showed an upward trend in the three intervention groups.PI3K and phospho-AKT protein levels were significantly increased in the EX+ISO group(P＜0.01,P＜0.05),and showed an increasing trend in the EMPA+ISO and EX+EMPA+ISO groups.Conclusions Moderate intensity aerobic exercise,the novel hypoglycemic drug EMPA,and their combination can alleviate ISO-induced pathological cardiac remodeling,possibly via a mechanism related to activation of the PI3K/AKT signaling pathway and inhibition of cardiac ferroptosis.

Objective To construct a short hairpin shRNA recombinant lentiviral vector targeting mouse VASP gene to interfere with the expression of VASP in mouse alveolar macrophage line(MH-S)cells.Methods shRNA targeting mouse VASP gene were de-signed,inserted into the shuttle plasmid GV644-EGFP vector,and identified by polymerization chain reaction(PCR)and sequencing.The recombinant plasmids GV644-VASP-shRNA-EGFP,auxiliary packaging pHelper 1.0 and pHelper 2.0 were co-transfected into 293T cells for packaging of recombinant lentivirus lenti-GV644-VASP-shRNA-EGFP,and titers were determined by fluorescent la-beling.MH-S cells were transfected with lenti-VASP-shRNA-EGFP at different multiple of infection(MOI)values,and the optimal MOI value was obtained according to the infection efficiency,and the expression of the target gene was detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)and Western blot.Results The shuttle plasmid GV644-VASP-shRNA-EGFP was successfully constructed by PCR and sequencing identification,and the recombinant lenti-VASP-shRNA-EGFP was further pack-aged with a viral titer of 2 × 109/(TU·ml),and the optimal MOI value of MH-S cells was 50,which significantly inhibited the expres-sion of VASP after infection with MH-S cells(P＜0.05).Conclusion In this study,the shRNA recombinant lentiviral vector targeting mouse VASP gene was successfully constructed,which significantly inhibited the expression of VASP in mouse MH-S cells,which laid a foundation for further exploring the role of VASP gene in macrophage phenotype regulation.

Objective To construct a short hairpin shRNA recombinant lentiviral vector targeting mouse VASP gene to interfere with the expression of VASP in mouse alveolar macrophage line(MH-S)cells.Methods shRNA targeting mouse VASP gene were de-signed,inserted into the shuttle plasmid GV644-EGFP vector,and identified by polymerization chain reaction(PCR)and sequencing.The recombinant plasmids GV644-VASP-shRNA-EGFP,auxiliary packaging pHelper 1.0 and pHelper 2.0 were co-transfected into 293T cells for packaging of recombinant lentivirus lenti-GV644-VASP-shRNA-EGFP,and titers were determined by fluorescent la-beling.MH-S cells were transfected with lenti-VASP-shRNA-EGFP at different multiple of infection(MOI)values,and the optimal MOI value was obtained according to the infection efficiency,and the expression of the target gene was detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)and Western blot.Results The shuttle plasmid GV644-VASP-shRNA-EGFP was successfully constructed by PCR and sequencing identification,and the recombinant lenti-VASP-shRNA-EGFP was further pack-aged with a viral titer of 2 × 109/(TU·ml),and the optimal MOI value of MH-S cells was 50,which significantly inhibited the expres-sion of VASP after infection with MH-S cells(P＜0.05).Conclusion In this study,the shRNA recombinant lentiviral vector targeting mouse VASP gene was successfully constructed,which significantly inhibited the expression of VASP in mouse MH-S cells,which laid a foundation for further exploring the role of VASP gene in macrophage phenotype regulation.

Objective:To evaluate the identification rate of separating gel or HB&L pretreatment methods of MALDI-TOF-MS, thereby to provide a new idea for the rapid and accurate identification of pathogens of bloodstream infections in daily clinic practice.Methods:A total of 149 alarmed positive blood culture samples of single bacterial infection by routine laboratory methods were collected between January to December 2020 from the Sixth Medical Center, Chinese PLA General Hospital. Samples were pretreated with the separation gel accelerating tube method or the HB&L microbial culture system, followed by direct MALDI-TOF MS bacterial identification, the identification rates of the two pretreatment methods were compared and results from the traditional method were used as the standard control.Results:Among the 149 positive blood culture samples, 47.0% (70/149) were gram-negative (G -) bacteria and 53.0% (79/149) were gram-positive (G +) bacteria. Identification rate of G -strain level was 78.6% (55/70) by serum separation gel coagulation tube method and 91.4% (64/70) by HB&L microbial culture system, the difference was statistically significant ( P=0.033). Identification rate of G +strain levels was 73.4% (58/79) by serum separation gel coagulation tube method and 87.3% (69/79) by HB&L microbial culture system, the difference was statistically significant ( P=0.028). For G -bacteria in the range of 3.000-2.300, the identification rate was 22.9% (16/70) by serum separation gel accelerating tube method and 38.6% (27/70) by the HB&L microbial culture system, the difference was statistically significant ( P=0.044). For G +bacteria in the range of 3.000-2.300, the identification rate was 19.0% (15/79) by serum separation gel accelerating tube method and 34.2% (27/79) by the HB&L microbial culture system, the difference was statistically significant ( P=0.031). Conclusion:The identification rate of HB&L microbial culture system is higher than that of serum separation gel coagulation tube method. Direct MALDI-TOF MS identification of pathogenic bacteria in positive blood culture samples after pretreatment is feasible in daily clinical practice.

Objective To investigate the mechanism of epidermal growth factor receptor-forkhead transcription factor A2 (EGFR-FOXA2) pathway-involved high secretion of mucus in human bronchial epitheli-um (HBE) cells after respiratory syncytial virus (RSV) infection and to evaluate the effects of intervention using agonist ( rosiglitazone ) and antagonist ( GW9662 ) of peroxidase proliferation activated receptor γ( PPARγ) and EGFR inhibitor ( AG1478 ) . Methods HBE cells were randomly divided into six groups: A group ( AG1478+RSV) , B group ( rosiglitazone+RSV) , C group ( GW9662+RSV) , D group ( RSV) , E group (0. 1％ dimethyl sulfoxide DMSO) and F group (HBE cell control group). Two hours before RSV infection, A, B and C groups were respectively treated with 10 μmol/L of AG1478, rosiglitazone and GW9662. Expression of EGFR, PPARγ and FOXA2 at mRNA level in each group was detected by real-time fluorescence quantitative RT-PCR 12 h, 24 h and 48 h after HBE cells were infected with or without RSV. Expression of phosphorylated-EGFR ( p-EGFR) and EGFR at protein level was detected by Western blot. ELISA was performed to measure the expression of mucin-5AC (MUC5AC). Results Compared with F group, EGFR expression at mRNA lev-el, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level were increased in a time-dependent manner in A, B, C and D groups at 12 h, 24 h and 48 h. Compared with group F, the expression of PPARγat mRNA level in A, B, and D groups increased at each time point. Moreover, PPARγ expression gradually in-creased over time in A and B groups, reaching the peaks at 48 h, but was in decline in D group. Expression of FOXA2 at mRNA level in RSV-infected HBE cells was declined at each time point compared with that in group F, especially in D group. Compared with group D, A and B groups showed significantly decreased EGFR ex-pression at mRNA level, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level, but markedly increased FOXA2 expression at mRNA level. Conclusions RSV infection increased the expression of MUC5AC at protein level in HBE cells. PPARγand EGFR-FOXA2 signaling pathways were involved in the hypersecretion of airway mucus during RSV infection.

Objective: To analyze the correlation between serum HBV DNA level and HBsAg titer in hepatitis B e antigen positive pregnant women without antiviral therapy, and investigate the impact of genomic variability of preS/S regions on their correlations. Methods: Prenatal serum samples from 882 pregnant women with chronic HBV infection who were positive for HBsAg, HBeAg and HBV DNA and were not on antiviral therapy were included in the analysis. The Abbott i2000 and m2000 systems were used to qualitatively or quantitatively detect HBsAg, HBeAg and HBV DNA levels, respectively. HBV genotyping was performed using a type-specific primer nested polymerase chain reaction (nPCR). In addition, serum samples of pregnant women with HBV DNA levels correlated with HBsAg titer and HBV DNA levels higher than HBsAg titers were used to perform preS/S region amplification by nPCR method. PCR products were directly sequenced and mutation sites were analyzed by MEGA6.0 stasticial software. Mann-Whitney U test was used for the measurement data, and 2-test test for count data. Correlations between variables were analyzed using Spearman’s rank correlation. Results: Serum HBsAg titer of HBeAg-positive pregnant women was positively correlated with HBV DNA level (r = 0.754, P < 0.01). Compared with the control group, mutation sites A60V (100% vs. 15.38%, χ² = 7.61, P < 0.01), V90A (100% vs. 30.77%, χ² = 4.43, P < 0.05) and I161T of HBV preS/S region (80.00% vs. 0, χ² = 9.14, P < 0.01) showed a significant decrease in HBsAg titer. Conclusion Serum HBV DNA levels were positively correlated with HBsAg titer in HBeAg-positive pregnant women. Therefore, serum HBsAg titer may be used as a surrogate marker of serum HBV DNA. Single or multiple amino acid mutations sites A60V, V90A, and I161T in preS/S region may be one of the reasons that lead to a significant drop in HBsAg titer and affect its correlation with HBV DNA levels.

Objective: To investigate the effects and mechanism of Holothurian Glycosaminoglycan (hGAG) alone in combination with cisplatin (DDP) on apoptosis of pulmonary adenocarcinoma cell A549. Methods: A549 cells were separately treated with blank, hGAG, DDP and hGAG combined with DDP (hGAG + DDP). The cell morphology in 4 groups was observed using light microscope. CCK8 assay was used to determine the cell viability. Flow cytometry by Hoechst 33258 and AnnexinV-FITC/PI staining was applied to detect cell apoptosis. Western blot was then used to detect the protein expression of Bax, Bcl-2, survivin and caspase-3. Results: After treatment for 24 h, the inhibitory rates of A549 cells in control, hGAG, DDP and hGAG + DDP groups were 0, (19.74±5.39)%, (42.01±2.57)% and (53.89±4.58)%, respectively. Moreover, after treatment for 48 h and 72 h, the inhibitory rates in each group were 0, (23.17±4.78)% and (29.17±4.21 )%, (54.00±7.64)% and (59.35±7.31)%, as well as (77.58±4.26)% and (79.94±4.58)%, respectively. The cell viability was significantly lower in drug treatment groups compared with those in control group at the same time point (P<0.05). Hochest 33258 staining showed that no obvious apoptotic cells were detected in the control group, while apoptotic cells were visible in hGAG, cisplatin and combination groups. Flow cytometry showed that cell apoptotic rates were (2.38±0.59)%, (12.59±4.22)%, (16.36±3.63)% and (44.60±5.45)% in the control, hGAG, DDP and hGAG + DDP groups, respectively. The cell apoptosis was significantly lower in drug treatment groups compared with those in control group at the same time point (P<0.05). Furthermore, western blot results showed that the expression of Bax and caspase-3 protein was increased (P<0.05), whereas Bcl-2 and survivin was decreased (P<0.05) in the hGAG+ DDP group compared with cisplatin alone (P<0.05). Conclusions HGAG can inhibit the proliferation and promote the apoptosis of human lung adenocarcinoma A549 cells. Meanwhile, it can strengthen the chemosensitivity of A549 cells to DDP via up-regulation of Bax, caspase-3 and down-regulation of Bcl-2 and survivin.

Based on the review of existed references,research methods and experiences of ethnographic studies of Chinese medicine in the UK,this article proposed several suggestions on the social scientific studies of Chinese medicine abroad under the background of the "Belt and Road":studies should be more pragmatic in order to take the role of think tank;multi-discipline studies are encouraged to take the advantages of professional subjects;multi-cultures should be respected and local conditions should be taken into consideration to achieve conversational communication and all-win interest consortium;qualitative research should be more emphasized to present more ethnographic work for analytical studies;historical studies should be paid attention to in order to get dynamic trends.