BACKGROUND:Hydrogels have become a research hotspot due to their unique advantages in the biomedical field due to their superior mechanical and biological properties.At present,related research involves tissue engineering,wound dressing and so on. OBJECTIVE:To review the advantages and properties of hydrogels and the research progress of their application in the repair of oral and maxillofacial defects,discuss the current limitations and challenges of hydrogels in application and promotion,and provide new ideas for future research directions. METHODS:Relevant literature was searched in PubMed,CNKI,and WanFang database by computer.The search terms were"hydrogel,oral and maxillofacial defects,mechanical properties,tissue engineering,wound dressing"in Chinese and"hydrogel,oral and maxillofacial defects,mechanical properties,guided tissue regeneration,wound dressing"in English.Preliminary screening was carried out by reading titles and abstracts,and articles not related to the topic of the article were excluded.According to the inclusion and exclusion criteria,108 articles were finally included for the result analysis. RESULTS AND CONCLUSION:(1)The hydrogel has good biological activity,mechanical controllability,and stimulation response.(2)Polymer,metal,and ceramic hydrogel composites have appropriate mechanical properties,biodegradability,and controlled release rate,which are suitable for maxillofacial bone tissue engineering.(3)Fibrin-based hydrogel could fill the hollow nerve conduit through the nerve defect area and promote the regeneration and growth of axons to restore the function of maxillofacial nerve.(4)Controlling the interaction between nanomaterials and hydrogels can improve the formation of muscle fiber oriented structure to promote maxillofacial muscle tissue regeneration.(5)Polysaccharide hydrogel has gradually become the first choice for repairing irregular periodontal defects due to its ability to control drug delivery,carry bioactive molecules,and combine with other materials to produce the best scaffold matching the extracellular matrix.(6)Calcium phosphate or calcium carbonate-based hydrogels can be used to fill irregular or fine tissue defects and remineralize hard tissues.The self-assembled hydrogels are simple to prepare and have good biological activity.(7)Salivary gland-derived extracellular matrix-like gel is expected to participate in the treatment of many salivary gland diseases.(8)Hydrogels can be used as wound dressings in combination with biological adhesives,acellular biomaterials,antimicrobials,antioxidants,or stem cells to treat various wounds.(9)Fibrin-based hydrogel has the most potential in the repair of oral and maxillofacial defects.It has excellent biocompatibility,flexibility,and plasticity.It can combine with cells,extracellular matrix proteins,and various growth factors,and promote the osteogenic differentiation of mesenchymal stem cells,axon regeneration and growth,angiogenesis,myotube differentiation,salivary gland tissue regeneration,and periodontal tissue regeneration.It has a broad prospect in the repair of oral and maxillofacial defects.However,its therapeutic effect depends on the function of the substance carried.The complex preparation process,its safety and long-term efficacy,and the special anatomical oral and maxillofacial structure is the problem that hinders its promotion,which also provides directions for future research.

BACKGROUND:This study provided insight into the molecular mechanisms by which exogenous basic fibroblast growth factor(bFGF)promotes wound healing. OBJECTIVE:To investigate the effect of exogenous bFGF on macrophage phenotype transition and granulation regeneration during wound repair in rats. METHODS:(1)In vitro experiment:Cells were divided into normal control group,low-dose bFGF group,high-dose bFGF group,and bFGF+valproic acid group.100 and 200 μg/L bFGF was added into the cell culture medium of low-dose bFGF group and high-dose bFGF group,respectively,while 200 μg/L bFGF and 20 mmol/L valproic acid were added into the cell culture medium of valproic acid group.EdU test,scratch test and tubule formation test were used to detect the effects of bFGF on proliferation,migration and angiogenesis of human umbilical vein endothelial cells.(2)In vivo experiment:Sprague-Dawley rats were randomly divided into model group,low-dose bFGF group,high-dose bFGF group and bFGF+valproic acid group.The open wound model of full-thickness skin defect was established in low-dose bFGF group,high-dose bFGF group and bFGF+valproic acid group.Rats in the low-and high-dose bFGF groups were given 100 and 200 μg/L bFGF through subcutaneous injection,while those in the bFGF+valproic acid group received subcutaneous injection of 200 μg/L bFGF and intraperitoneal injection of 10 mg/kg valproic acid.The wound healing rate of rats was detected at 7 and 14 days of administration.TUNEL was used to detect the apoptosis of cells in wound tissue.Enzyme linked immunosorbent assay was used to detect the serum levels of malondialdehyde,superoxide dismutase,tumor necrosis factor-α and interleukin-10.Immunofluorescence detection was conducted to detect the phenotypic transformation of macrophages in wound tissue.Immunohistochemistry was used to detect the expression of proliferating cell nuclear antigen,platelet endothelial cell adhesion molecule-1(CD31)and vascular endothelial growth factor in wound tissue.Western blot was used to detect the expression of Notch1 and Jagged1 in wound tissue. RESULTS AND CONCLUSION:(1)Compared with the normal control group,bFGF could significantly promote the proliferation,migration and angiogenesis of human umbilical vein endothelial cells in a dose-dependent manner.(2)Compared with the model group,bFGF could significantly promote wound healing,downregulate the rate of apoptosis in wound tissue,decrease the levels of malondialdehyde and tumor necrosis factor-α in serum,increase the levels of superoxide dismutase and interleukin-10,promote the conversion of macrophages to type M2 in wound tissue,upregulate the expression of proliferating cell nuclear antigen,CD31 and vascular endothelial growth factor in wound tissue,and inhibit the expression of Notch1 and Jagged1 in a dose-dependent manner.Valproic acid could partially reverse the promoting effect of bFGF on wound healing.To conclude,bFGF can significantly promote wound healing and granulation regeneration and induce the conversion of macrophages to M2,which may be related to the regulation of Notch1/Jagged1 signaling pathway.

Objective A non-targeted metabolomics analysis of vitreous fluid from patients with proliferative diabetic retinopathy(PDR)is conducted to explore the"metabolic map"of PDR.This approach aims to deepen the understanding of the disease,identify potential biomarkers.Methods From 35 PDR patients and 30 fresh rhegmatogenous retinal de-tachment(RRD)patients,10 PDR patients with vitreoretinal abnormal adhesions were selected as the experimental group(PDR group),and 10 fresh RRD patients were chosen as the control group(RRD group).Using ultra-high-performance liq-uid chromatography-mass spectrometry non-targeted metabolomics technology,the metabolic profiles of vitreous fluid were analyzed to obtain metabolic spectra.One-dimensional and multidimensional statistical methods were used to analyze the differences in metabolites and metabolic pathways between the PDR and RRD groups.Results A total of 165 differential metabolites were identified in the vitreous humor samples of patients in the PDR and RRD groups,these differential metab-olites were significantly enriched in 21 metabolic pathways(P＜0.05),Among these pathways,those with at least 5 differ-ential metabolites include:methionine and cysteine metabolism;glycine,serine,and threonine metabolism;ascorbic acid and aldose metabolism;amino acid biosynthesis;and central carbon metabolism in cancer.Pyruvate,serine,D-2-phospho-glycerate,threonine,phosphoserine,and high serine are present in multiple metabolic pathways,the areas under the curve are 0.96,0.82,0.85,0.78,0.40,and 0.31,respectively.Conclusion There are 21 significantly different metabolic pathways between PDR and RRD patients.Pyruvate stands out in multiple pathways,potentially serving as a biomarker for PDR diagnosis.

The aim of this study is to establish an gene editing method of Mesomycoplasma hyo-pneumoniae(Mhp)based on the homologous recombination principle.The restriction enzyme di-gestion and ligation method combined with gene synthesis were used to construct a shuttle plasmid to achieve replication in both Mhp and Escherichia coli(E.coli).The pGEM?-T vector was used as the skeleton.The oriC sequence of Mhp which can achieve the replication of the plasmid in Mhp was inserted into the vector.Sequences of the Spiroplasma promoter and puromycin resistance gene were then inserted into the above constructed plasmid to screen recombinant clones.The up-stream and downstream homologous arms of p97 were constructed to initiate homologous recombination.The recA gene of E.coli is inserted to improve the efficiency of homologous recom-bination.The obtained shuttle plasmid was then delivered into Mhp by electro-transformation or chemical transformation.A shuttle plasmid,pGEM?-Mhp-oriC-p 97,which can replicate in both Mhp and E.coli was constructed.With the transformation of this plasmid,the carried puromycin gene and recA gene can be expressed,the p97 gene can be edited.Finally,the genetically unstable p97 gene mutant was initially obtained.In this study,a tool for Mhp gene editing based on the principle of homologous recombination was established,which laid a foundation for the develop-ment of tools for studying the pathogenesis of Mhp.

Objective It investigates the current status of negative defensive medical behavior tendencies among medical students and explores influencing factors,aiming to provide evidence for improving medical students' propensity for negative defensive medical practices.Methods In February 2023,a cluster sampling approach was employed to recruit 297 medical students from a medical college-affiliated hospital in Province H.Descriptive statistics,chi-square tests,and correlation analyses were conducted to assess negative defensive medical behavior tendencies.Structural equation modeling(SEM)was utilized to explore multidimensional influencing factors.Results 45％of medical students demonstrated high-level negative defensive medical behavior tendencies.Statistically significant differences were observed between genders(x2=5.569,P＜0.05)and only-child/non-only-child groups(x2=6.104,P＜0.05).Positive correlations were identified between negative defensive medical behaviors and role stress(r=0.217,P＜0.01),negative organizational environment evaluation(r=0.395,P＜0.01),and negative social environment evaluation(r=0.405,P＜0.01).Only-child status was confirmed as an influencing factor(β=-0.123,P=0.036).Negative organizational environment evaluation(β=0.504,P＜0.001)and negative social environment evaluation(β=0.193,P=0.039)showed significant positive effects.Conclusion Immediate interventions-including role-specific risk allocation,organizational ecosystem reconstruction,and social environment governance-require urgent implementation to address early-stage behavioral deviance,counteract the solidification of defensive medical thinking patterns,and reduce predispositions toward negative professional behaviors among medical trainees.

Objective To evaluate the efficacy and safety of Qixian Tongluo Formula in the treatment of post-cerebral infarction paralysis with kidney deficiency and blood stasis syndrome,and to preliminarily explore the molecular mechanism of Qixian Tongluo Formula in improving impaired motor function from the perspective of cross-kingdom regulation of Chinese medicine microRNA(miRNA).Methods A pragmatic randomized controlled trial was conducted with 102 patients in the recovery period of post-cerebral infarction paralysis with kidney deficiency and blood stasis syndrome in our hospital.Patients were randomly divided into trial group and control group,with 51 cases in each group.The control group received standard Western medicine standard treatment,while the trial group received Qixian Tongluo Formula in addition to the standard treatment,with one dose per day,boiled in water,and taken warm after breakfast and dinner for a course of 2 months.The disability rate was used as the main efficacy indicator,and the incidence of adverse reactions was used as a safety indicator.miRNA from patient serum and Qixian Tongluo decoction were extracted respectively,and high-throughput sequencing was performed.The two sequences were compared to screen out the cross-kingdom gene transfer of Chinese medicine miRNA.Finally,its target genes of miRNA were predicted,and GO function and KEGG pathway enrichment analysis were carried out.Results A total of 67 patients completed the clinical trial,including 36 cases in the trial group and 31 cases in the control group;The disability rate in the trial group(13.9%)was lower than that in the control group(35.5%)(P<0.05);The incidence of adverse reactions was similar between the trial group(7.69%)and the control group(6.06%)(P>0.05);A total of 9530 Qixian Tongluo decoction miRNA sequences were screened,with 150 potentially involved in cross-kingdom gene transfer,including families such as miR-15 and miR-17;According to the target gene prediction of the top 10 miRNAs in cross-kingdom gene transfer of Chinese medicine,345 overlapping target genes were obtained;GO functional enrichment analysis revealed 16 biological processes,7 cellular components,and 2 molecular functions among the top 25 enriched functions,while KEGG pathway analysis mainly focused on the transforming growth factor-βsignaling pathway,neurotrophin signaling pathway,which are closely related to neural repair and functional recovery processes such as glial scar formation and synaptic plasticity after cerebral ischemia.Conclusion Qixian Tongluo Formula can significantly improve the functional independence level of patients with kidney deficiency and blood stasis syndrome in the recovery period of paralysis after cerebral infarction,offering a safe and effective treatment option for these patients;There were a large number of miRNAs in Qixian Tongluo decoction,some of which could cross-kingdom transferred into the human blood circulation,and promote the recovery of motor function in patients with cerebral infarction through multi-target,multi link and multi pathway gene network regulation.This study provides a new idea for subsequent clinical and basic research.

OBJECTIVE To screen and obtain nanobodies with neutralizing activity against granulo-cyte-macrophage colony stimulating factor(GM-CSF)to contribute to investigations into the mecha-nism of inflammation interventions and the development new drugs.METHODS Recombinant human GM-CSF was subcutaneously injected to immunize camels.Peripheral blood was collected after five immunizations,and mononuclear cells were isolated.Total mRNA was extracted,and the variable domains of the heavy chain of heavy-chain antibody(VHH,also called nanobody)genes were obtained by PCR amplification after reverse transcription.The genes were cloned into the pADSCFV-S phage display vector and electrotransformed into TG1 competent cells to construct a nanobody immune library that was screened with recombinant human GM-CSF immobilized on a solid phase.The VHH genes specifi-cally binding to human GM-CSF were cloned into the pABG eukaryotic expression vector before VHH-Fc samples were prepared by using the human embryonic kidney 293 fibroblast expression system.The binding activity of candidate VHH-Fc molecules to GM-CSF was investigated through ELISA response curves,and binding colorimetric values with different antigens were detected to determine their specificity.The binding affinity between VHH-Fc candidates and GM-CSF was measured using biolayer interferom-etry(BLI).The inhibition rate curve of VHH-Fc candidates on GM-CSF was detected through cell prolif-eration assays to determine its neutralization activity.The Uncle system was used to investigate its thermal stability.100 μg of VHH-Fc was injected into mice via the tail vein,and the serum concentration of VHH-Fc was quantitatively detected by ELISA to examine its pharmacokinetic curve in mice.RESULTS The camel serum titer of anti-human GM-CSF antibodies was higher than 1:800 000 after the fifth immuni-zation,and the capacity of the constructed nanobody library was about 5.55×107.Following the screening process,five candidate VHH-Fc molecules specifically binding to human GM-CSF were obtained.Among these,22N10 effectively neutralized the cell proliferation-promoting activity of GM-CSF(the IC50 value was 17.23 nmol·L-1).Subsequent studies revealed that 22N10 interacted with human GM-CSF with an affinity of 1.97×10-8 mol·L-1,blocked the binding of GM-CSF to its receptor CSF2Rα,exhibited good thermal stability(Tm1=59.2℃),and showed favorable metabolic characteristics in mice.CONCLU-SION A new candidate nanobody molecule 22N10 targeting human GM-CSF is obtained which is expected to facilitate the drug development and mechanism investigations.

Objective:To explore the impacts of different frequencies of orthogonal image-guided verification on set-up error correction and the reference values of planning target volume (PTV) margins in postoperative radiotherapy for breast cancer, in order to provide recommendations of the verification frequency in clinical practice.Methods:A total of 80 breast cancer patients who received postoperative intensity-modulated radiotherapy for breast cancer at the Affiliated Union Hospital of Fujian Medical University from January 2021 to January 2022 were enrolled. Orthogonal image-guided verification was conducted before each radiation treatment to determine initial and residual set-up errors. The error data were statistically analyzed by categorizing patients into groups A, B, C, D, E, and F, based on assumed verification frequencies (daily, every 2, 3, 4, and 5 d, and no correction). The magnitude, distribution, and differences of set-up errors of various groups were analyzed, and the PTV margins were calculated using a reference formula.Results:The collected initial set-up errors of the 80 patients were (3.49±3.43), (2.87±2.88), and (2.75±2.35) mm, in x, y, and z directions, respectively. The residual set-up errors decreased gradually with increasing verification frequency. In the case of daily image-guided verification, the residual set-up errors in x, y, and z directions decreased to (1.63±0.90), (1.63±0.93), and (1.55±0.90)mm, respectively. The reference values of PTV margins calculated under different verification frequencies decreased with an increase in the verification frequency. Under daily verification, the reference values of PTV margins calculated based on set-up errors decreased from initial 6.60, 6.29, and 4.22 mm (without correction) to 1.27, 1.37, and 1.28 mm, respectively. Differences in the reference values under verification frequencies every 3, 4, and 5 d were less than 0.81 mm. Conclusions:Daily image-guided verification (including correction) can effectively reduce set-up errors in image-guided radiotherapy for breast cancer. The set-up errors differ under varying verification frequencies, with a higher frequency corresponding to better correction effects and smaller PTV margins required.

In order to establish a simple,sensitive and specific diagnostic method for the simultane-ous detection of Mycoplasma hyorhinis(Mhr)and Mycoplasma hyopneumoniae(Mhp)in swine,specific primers and probes were designed using the Mhr p37 and Mhp p36 gene sequences as the target genes,and the dual LFD-RPA rapid test was established by screening the primers and probes,optimizing primer ratios and evaluating its effectiveness through the sensitivity,reproduc-ibility and clinical sample testing.The sensitivity,specificity,reproducibility and clinical samples were evaluated.The results showed that the established dual LFD-RPA assay could complete the amplification in 15 min at 39 ℃,and its optimal primer ratio was 1.6∶0.8,and the lowest detection limits were up to 3.63 and 3.60 copies/μL,respectively;the reproducibility was stable;and there was no cross-reactivity with Pasteurella multocida,Bordetella bronchiseptica,Haemophilus pa-rasuis,Actinobacillus pleuropneumoniae,Escherichia coli.The test successfully established a dual LFD-RPA assay,which can detect Mhr and Mhp simultaneously,and is simple,sensitive and spe-cific without relying on specialized equipment,and is suitable for carrying out on-site rapid diagno-sis of Mhr and Mhp.

In this study,the carboxylated magnetic beads were coupled with bivalent nanobodies a-gainst porcine epidemic diarrhea virus(PEDV)M protein to construct immunomagnetic beads(IM-NBs-Ⅱ),The capture and enrichment function of IMNBs-Ⅱ was verified by using PEDV propaga-ted in Vero cells.A one-step RT-qPCR detection method for PEDV was established by combining the characteristics of IMNBs-Ⅱ with the detection advantages of reverse transcription fluorescence quantitative polymerase chain reaction(RT-qPCR).Specific analysis found that this method has no cross reactivity with swine fever virus,porcine reproductive and respiratory syndrome virus,por-cine parvovirus,porcine circovirus,indicating that it has good specificity.Sensitivity analysis re-vealed that the detection sensitivity of the RT-qPCR based on IMNBs-Ⅱ was increased 10 times compared to traditional RT-qPCR methods.Detection of the clinical samples confirm that the RT qPCR method based on IMNBs-Ⅱ is suitable for rapid and accurate detection of clinical feces and tissue samples.The method established in this study effectively avoids contamination issues during nucleic acid extraction,simplifies experimental procedures,and saves detection time,which pro-vides a method for efficient detection of PEDV.