BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

BACKGROUND:The osteogenic differentiation ability of exosomes derived from osteogenic mesenchymal stem cells is well established.However,their impact on the osteogenic differentiation of human periodontal ligament stem cells in an inflammatory microenvironment remains unclear. OBJECTIVE:To examine the impact of exosomes derived from osteogenesis-induced human periodontal ligament stem cells on the osteogenic differentiation of human periodontal ligament stem cells within an inflammatory microenvironment. METHODS:Human periodontal ligament stem cells were isolated and cultured.After 3 days of osteogenic induction,exosomes were extracted.Human periodontal ligament stem cells were divided into four groups.Control group was treated with osteogenesis-induced medium.The exosome group was treated with osteogenesis-induced medium containing 5 μg/mL exosomes.Inflammatory model and inflammatory model+exosome groups were treated with 1 μg/mL lipopolysaccharide for 24 hours to construct a cellular inflammatory microenvironment.The inflammatory model group was treated with osteogenesis-induced medium after lipopolysaccharide intervention.The inflammatory model+exosome group was treated with osteogenesis-induced medium containing 5 μg/mL exosome.The osteogenic differentiation ability of human periodontal ligament stem cells was assessed using alkaline phosphatase staining and alizarin red staining.The expressions of Runt-related transcription factor 2,osteopontin,osteoblast-specific transcription factor Osterix(OSX)and wnt pathway-related protein β-catenin were detected by real-time fluorescence quantitative PCR and western blot assay. RESULTS AND CONCLUSION:(1)Compared with the control group,the relative area stained by alkaline phosphatase,the relative area stained by mineralized nodules and the expression levels of Runx2,osteopontin,and OSX were significantly decreased in the inflammatory model group(P<0.05).(2)Compared with the inflammatory model group,the expression of Runx2,osteopontin,and OSX in the inflammatory model+exosome group was significantly increased in the relative area of alkaline phosphatase staining,the relative area of mineralized nodules staining(P<0.05).(3)Compared with the control group,the expression of wnt pathway-related protein β-catenin was significantly increased in the inflammatory model group(P<0.05).Compared with the inflammatory model group,the expression of β-catenin in the inflammatory model+exosome group was significantly decreased(P<0.05).These findings indicate that exosomes derived from human periodontal ligament stem cells induced by bone formation can enhance the osteogenic differentiation of human periodontal ligament stem cells within an inflammatory microenvironment,and the mechanism may be related to wnt/β-catenin signaling pathway.

ObjectiveTo observe the clinical effectiveness and safety of Xiaozhong Zhitong Mixture （消肿止痛合剂） combined with antibiotic bone cement in the treatment of diabetic foot ulcer （DFU） with damp-heat obstructing syndrome. MethodsA total of 72 DFU patients with damp-heat obstructing syndrome were randomly assigned to treatment group （36 cases） and the control group （36 cases）. Both groups received standard treatment and topical antibiotic bone cement for ulcer wounds， while the treatment group received oral Xiaozhong Zhitong Mixture （50 ml per time， three times daily） in additionally. Both groups underwent daily wound dressing changes for 21 consecutive days. Ulcer healing rate， serum levels of tumor necrosis factor-alpha （TNF-α）， interleukin-1 beta （IL-1β）， malondialdehyde （MDA）， superoxide dismutase （SOD）， C-reactive protein （CRP）， and white blood cell （WBC） count were observed before and after treatment， and visual analog scale （VAS） scores for wound pain， traditional Chinese medicine （TCM） syndrome scores， and the DFU Healing Scale （DMIST scale） were also compared. Liver and kidney function were evaluated before and after treatment， and adverse events such as allergic reactions， worsening ulcer pain were recorded. ResultsTotally 35 patients in the treatment group and 33 in the control group were included in the final analysis. The ulcer healing rate in the treatment group was （87.93±9.34）%， significantly higher than （81.82±12.02）% in the control group （P = 0.035）. Compared to pre-treatment levels， both groups showed significant reductions in serum CRP， WBC， MDA， IL-1β， and TNF-α levels， with an increase in SOD level （P＜0.05）. TCM syndrome scores， VAS， and DMIST scores also significantly decreased in both groups （P＜0.05）， with greater improvements in the treatment group （P＜0.05）. No significant adverse reactions were observed in either group during treatment. ConclusionXiaozhong Zhitong Mixture combined with antibiotic bone cement has significant advantages in promoting DFU healing， reducing inflammatory response， and alleviating oxidative stress in DFU patients with damp-heat obstructing syndrome， with good safety for DFU patients with damp-heat obstructing syndrome.

OBJECTIVE To optimize the forming process of Yindan huoxue tongyu granules， and evaluate the quality of the granules. METHODS Taking forming rate， angle of repose， moisture， moisture absorption rate and dissolution rate as indexes， single factor experiment combined with Plackett-Burman design was adopted to screen key process parameters； analytic hierarchy process combined with entropy weight method and Box-Behnken response surface method were used to optimize the molding process of Yindan huoxue tongyu granules， and the forming process was verified. The relative homogeneity index， bulk density， vibration density， Hausner ratio， angle of repose， moisture and hygroscopicity were used as secondary physical indexes to establish the physical fingerprints of 10 batches of Yindan huoxue tongyu granules to evaluate particle quality consistency. RESULTS The optimal molding process of Yindan huoxue tongyu granules was as follows： mannitol as the fixed excipient， the drug-assisted ratio was 1∶1（m/m） and the drying time was 1 h； 90% ethanol was used as wetting agent and the amount of it was 32%， the drying temperature was 70 ℃. The results of validation tests showed that the average comprehensive score was 97.45， which was close to the predicted value of 97.18. The similarities between the physical fingerprints of 10 batches of Yindan huoxue tongyu granules prepared by the optimal molding process and the reference physical fingerprint were all higher than 0.99. CONCLUSIONS The molding process is stable and feasible， and the quality of Yindan huoxue tongyu granules produced is stable and controllable.

Diabetic ulcer （DU） wound is one of the chronic and serious complications of diabetes characterized by prolonged wound healing， and it is more common in foot and lower extremity ulcers. DU has brought great economic and psychological pressure to patients and seriously affected the quality of life of patients because of its great difficulty in treatment， long treatment process， and high morbidity and mortality. Therefore， how to help the rapid healing of DU wounds， reduce the disability rate and mortality rate， protect limb function， and improve the quality of life is an important topic and hot spot in the field of medical research. The pathogenesis of DU is complex， mainly including microcirculation disorder， peripheral neuropathy， inflammation and infection， and excessive apoptosis of cells， involving physiological processes such as wound inflammation， granulation tissue hyperplasia and re-epithelialization. A large number of previous studies have found that Chinese medicine can regulate phosphatidylinositol 3-kinase/protein kinase B （PI3K/Akt）， Wnt/β-catenin， nuclear factor-κB （NF-κB）， Notch， nuclear factor E₂-related factor 2 （Nrf2）， transforming growth factor-β （TGF-β）/Smad， and other signaling pathways， regulate abnormal glucose metabolism， improve microcirculation， inhibit inflammation and oxidative stress， regulate cell proliferation and excessive apoptosis， and promote wound tissue growth to promote the rapid healing of DU wounds under the guidance of treatment based on traditional Chinese medicine （TCM） syndrome differentiation and internal and external treatment. Therefore， this paper reviewed Chinese medicinal monomers or Chinese medicinal compounds in recent years in regulating the above signaling pathways and the expression of key protein molecules and promoting the rapid healing of DU wounds， aiming to provide ideas and a theoretical basis for the in-depth study and clinical application of Chinese medicine in promoting the healing of DU wounds.

This study was designed to explore the effect of DNA methyltransferase 1(DNMT1)on podocyte apoptosis and inflammatory cytokine release induced by high glucose(HG),and analyze the related molecular mechanisms.Podocyte MPC-5 cells were cultured in vitro and divided into control and HG groups.DNMT1 and SOCS1 were either silenced or overexpressed using small RNA interference technology and liposome transfection technology.The expression levels of DNMT1 and SOCS1 genes were measured using qRT-PCR.Apoptosis was assessed by flow cytometry,while ELISA was employed to determine the levels of inflammatory factors such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),interleukin-1β(IL-1β),and monocyte chemoattractant protein-1(MCP-1).Western blot was used to detect the expression of DNMT1,SOCS1 proteins,and the proteins involved in the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathway.Data showed that HG elevated MPC-5 cell apoptosis rate,the level of inflammatory factors and DNMT1 mRNA expression,and the expression of DNMT1,p-JAK2 and p-STAT3 proteins,while reduced SOCS1 mRNA and protein expression(P＜0.05).Both silencing DNMT1 and overexpressing SOCS1 resulted in reduce of MPC-5 cell apoptosis rate,inflammatory factors level,p-JAK2 and p-STAT3 proteins expression(P＜0.05).Additionally,silencing DNMT1 increased SOCS1 mRNA and protein expressions(P＜0.05).Conversely,silencing SOCS1 counteracted the effects of DNMT1 silencing on MPC-5 cell apoptosis,inflammation,p-JAK2 and p-STAT3 proteins expression.Therefore,silencing DNMT1 expression can reduce the apoptosis and inflammation of podocytes induced by HG,and its mechanism may be related to the inhibition of JAK2/STAT3 signaling pathway activation by upregulating SOCS1 expression.

Objective To analyze the relationship between microorganisms and endodontic disease by using 16S rDNA sequencing to compare the composition of the microbial community in the root canals of teeth with pulpitis and apical periodontitis.Methods Clinical samples were collected from teeth requiring root canal treatment.The to-tal DNA of the bacteria in the samples and the gene fragments of the V3-V4 highly variable region on the 16S rDNA fragments were amplified through PCR.After sequencing by NovaSeq,statistical and bioinformatic analysis,inclu-ding phylogenetic analysis,diversity analysis and analysis of group differences,were performed.Results In total,6 teeth with pulpitis and 7 teeth with apical periodontitis were collected,and a total of 8 510 OTUs were obtained after next-generation sequencing,and the analysis of bacterial diversity showed that the difference between pulpitis and apical periodontitis in terms of the composition of the bacterial flora was statistically significant(P＜0.05).In particular,the relative abundance of Proteobacteria,Acidobacteriota and Actinobacteriota phylum was significantly higher in the roots of teeth affected by pulpitis than apical periodontitis.The relative abundance of Bacteroidota phylum and Synergistota phylum was significantly higher in the root canals of teeth with apical periodontitis.Con-clusion There is a complex diversity of infecting microorganisms in the root canals of teeth affected by endodontic diseases.The microbial communities in the infected root canals of pulpitis and apical periodontitis show some differ-ences,and changes in the microbial composition of the root canals may be associated with the development of endo-dontic diseases.

Objective　To explore the effect of Mp1p on host macrophages through transcriptomics combined with metabolomics. Methods Firstly, a THP-1 macrophage strain (THP-1-Mp1p+) stably expressing Mp1p was constructed using lentivirus. Secondly, using high-throughput RNA sequencing (RNA Seq) technology, the expression level of intracellular mRNA was detected in transcriptomics analysis to determine differentially expressed genes; In metabolomics analysis, metabolite identification was performed through database comparison, and pathway analysis was performed on differential metabolites to reveal potential mechanisms of action. Finally, the results of metabolomics and transcriptomics were combined for analysis, and differential metabolites and genes were analyzed to further elucidate the mechanism of action of Mp1p on macrophages. Results Transcriptome analysis showed that, compared with the negative control group, the THP-1-Mp1p+ group had a total of 1 180 differentially expressed genes (DEGs), with 345 upregulated genes and 835 downregulated genes. GO enrichment analysis of DEGs showed that there were 135 differentially expressed genes, including 105 in biological processes (BP), 28 in cellular components (CC), and 2 in molecular functions (MF). The KEGG analysis results showed that the effect of Mp1p on THP-1 macrophages was highly correlated with the TNF pathway. The metabolomic analysis found that both the blank control group and the THP-1-Mp1p+ macrophage group achieved good separation between QC samples in both positive and negative ion modes. The threshold for significant differential metabolites was set at: VIP≥1 and T-test P<0.05, resulting in the identification of 488 differential metabolites, with 230 in the positive ion mode and 258 in the negative ion mode. Pathway enrichment analysis of the identified metabolites pointed to significant enrichment in metabolic pathways. The combined analysis confirmed that the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and NF-kappaB signaling pathway were important metabolic pathways involved. Conclusions The virulence factor Mp1p may affect host macrophages by modulating the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and NF-kappaB signaling pathway. The findings contribute to a better understanding of the mechanisms of action of Mp1p and may offer potential directions for the selection of relevant diagnostic and therapeutic targets in the future.

Objective:To investigate the effects of Porphyromonas gingivalis derived outer membrane vesicles (Pg OMV) on osteoclast differentiation of macrophages and its underlying mechanisms. Methods:The morphology and the size distribution of Pg OMV were analyzed by transmission electron microscopy and nanoparticle tracing analysis, respectively. The osteoclast precursors were treated with 1, 3 and 10 mg/L Pg OMV (1, 3 and 10 mg/L OMV treatment group) or phosphate buffer solution (PBS)(control group). The formation of osteoclasts was analyzed by tartrate-resistant acid phosphase (TRAP) staining and F-actin staining and real-time quantitative PCR (RT-qPCR) were used to detect the expression of Fos and matrix metallopeptidase 9 (MMP9). Polymyxin B (PMB) was used to block lipopolysaccharide (LPS) and then Pg OMV was used to treat osteoclast precursor (PMB-OMV treatment group), and OMV treatment group was used as control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The effect of Pg OMV on the expression of Toll-like receptor (TLR) 2 and TLR4 in preosteoclasts was detected by Western blotting. The osteoclast precursors were pretreated with 10, 50, 100 and 200 μmol/L C29, an inhibitor of TLR2, and then treated with Pg OMV(OMV+10, 50, 100 and 200 μmol/L C29 treatment group) and OMV treatment group without C29 pretreatment was control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The osteoclast precursor cells were treated with OMV (OMV treatment group) and OMV incubated with PMB (PMB-OMV treatment group) and the expression of TLR2 in osteoclast precursor was detected by Western blotting.Results:Pg OMV showed classical vesicular structures, and the average particle size of Pg OMV were 179.2 nm. A large number of actin rings were observed in the 3 and 10 mg/L OMV treatment groups. The percentages of TRAP-positive osteoclast area in 3 mg/L OMV treatment group [(22.6±2.1)%] and 10 mg/L OMV treatment group [(32.0±2.3)%] were significantly increased compared with control group [(4.9±0.5)%] ( P<0.001). Compared with the control group (1.000±0.029), the mRNA relative expression of Fos in 3 mg/L OMV treatment group (1.491±0.114) and 10 mg/L OMV treatment group (1.726±0.254) was significantly increased ( P=0.013, P=0.001). Compared with the control group (1.007±0.148), the mRNA relative expression of MMP9 in the group of 10 mg/L OMV (2.232±0.097) was significantly increased ( P<0.001). Actin ring formation was less in PMB-OMV treatment groups than in OMV treatment groups. The proportion of TRAP-positive osteoclasts area [(14.8±3.8)%] in PMB-OMV treatment group was significantly lower than OMV treatment group [(31.5±6.7) %] ( P=0.004). The relative expression of TLR2 in OMV treatment group (1.359±0.134) was significantly higher than that in the control group (1.000±0.000) ( t=4.62, P=0.044). Compared with the OMV treatment group [(29.4±1.7)%], 50, 100 and 200 μmol/L C29 significantly decreased the formation of osteoclasts [(24.0±1.7)%, (18.5±2.1)%, (9.1±1.3) %] ( P=0.026, P<0.001, P<0.001). TLR2 protein expression in PMB-OMV group (0.780±0.046) was significantly lower than that in OMV group (1.000±0.000)( t=8.32, P=0.001). Conclusions:Pg OMV can promote osteoclast differentiation by carrying LPS, TLR2 plays an important role in Pg OMV mediated osteoclast differentiation.