Objective To express nucleoprotein(NP) of influenza A virus in Bac-to-Bac TOPO system and evaluate its immunogenicity,so as to lay a foundation for the research of influenza virus NP protein vaccine.Methods The NP gene of influenza A H1N1(A/Guangdong-Maonan/SWL1536/2019_CNIC-1909) was amplified by PCR and connected to the vector pFastBac~(TM)/CT-TOPO~(TM),which was transformed into competent E.coli One Shot~(TM) Mach1~(TM) T1~R to prepare donor plasmid,and identified by PCR and sequencing.The donor plasmid was transformed into competent E.coli MAX Efficiency~(TM) DH10Bac~(TM),the positive monoclone was screened by blue-white spot screening,and the recombinant bacmid was extracted and identified by PCR.The recombinant bacmid was transfected into Sf9 insect cells to prepare the recombinant baculovirus,and the virus titer was detected by flow cytometry.After multiple rounds of amplification,the recombinant baculovirus infected Sf9 insect cells for the expression of the target protein NP,and the recombinant protein was purified by nickel ion affinity chromatography.Female BALB/c mice were subcutaneously inoculated with recombinant NP protein and PBS respectively,with six mice in each group.The serum specific antibody levels of mice were detected by ELISA,the IFN-γ secreted by spleen cells were detected by flow cytometry,and the CD4~+ and CD8~+ lymphocytes produced by spleen cells were detected by ELISpot.Two weeks after the last immunization,the mice were challenged with A/Guangdong Maonan/SWL 1536/2019_CNIC-1909 influenza virus through nasal cavity,and the body mass changes and survival rate of mice within 14 days after challenge were monitored.Results The results of PCR and sequencing showed that the donor plasmid was constructed correctly.PCR identification results confirmed that the recombinant bacmid was successfully constructed.The titer of recombinant baculovirus was 2.875 × 10~8ivp/mL.The recombinant NP protein showed specific binding to mouse anti-influenza A virus NP monoclonal antibody,with the purity of 91.3% after purification.Two weeks after the last immunization,compared with the PBS group,the serum specific antibody titer(t=0.288,P <0.000 1),the average number of IFNγ spots produced by spleen cells(t=9.235,P <0.000 1),and the number of CD4~+ and CD8~+T lymphocytes produced(t=10.870 and 6.200,P=0.008 4and 0.025 0,respectively) in mice of NA group increased significantly.The mice in PBS group all died within 5 days after infection,while in NP group,one mouse died 5 days after infection,and the other five mice survived.Conclusion The NP protein of influenza A virus expressed by Bac-to-Bac TOPO system has high immunogenicity and can produce strong humoral and cellular immune responses,which can provide certain protection for mice against influenza virus infection.

Acute-on-chronic liver failure （ACLF） is an acute and critical illness with a high short-term mortality rate， and current therapies mainly focus on elimination of causes， organ support， and prevention of complications. Although liver transplantation is the most effective treatment modality， its clinical application is limited， and traditional Chinese medicine has shown significant advantages and characteristics in the treatment of ACLF. In traditional Chinese medicine， ACLF is classified into the same category as diseases such as “jaundice”， and unlike traditional jaundice which is mostly characterized by excess and heat syndromes， the syndrome of ACLF has gradually transformed from Yang jaundice to Yin jaundice due to the changing disease spectrum of ACLF. With reference to the pathogenesis of ACLF in Western medicine and traditional Chinese medicine theories， this article discusses the essential pathogenesis of ACLF in traditional Chinese medicine， explores the evolution of ACLF syndromes， and reviews the research advances in the clinical efficacy and mechanisms of traditional Chinese medicine based on the three-factor differentiation-based treatment of damp-heat， blood stasis-heat， and spleen deficiency， as well as the safety of spleen-strengthening and Yang-warming drugs in the clinical treatment of ACLF， in order to provide ideas， methods， and evidence for the application of traditional Chinese medicine in ACLF.

Objective To develop and validate a deep learning model for automatic identification of liver CT contrast-enhanced phases.Methods A total of 766 patients with liver CT contrast-enhanced images were retrospectively collected.A three-phase classification model and an arterial phase(AP)classification model were developed,so as to automatically identify liver CT contrast-enhanced phases as early arterial phase(EAP)or late arterial phase(LAP),portal venous phase(PVP),and equilibrium phase(EP).In addition,221 patients with liver CT contrast-enhanced images in 5 different hospitals were used for external validation.The annotation results of radiologists were used as a reference standard to evaluate the model performances.Results In the external validation datasets,the accuracy in identifying each enhanced phase reached to 90.50%-99.70%.Conclusion The automatic identification model of liver CT contrast-enhanced phases based on residual network may provide an efficient,objective,and unified image quality control tool.

ObjectiveTo explore the syndrome elements and evolving patterns of patients with hepatitis B virus-related acute on chronic liver failure （HBV-ACLF） at different stages. MethodsClinical information of 1,058 hospitalized HBV-ACLF patients， including 618 in the early stage， 355 in the middle stage， and 85 in the late stage， were collected from 18 clinical centers across 12 regions nationwide from January 1， 2012 to February 28， 2015. The “Hepatitis B-related Chronic and Acute Liver Failure Chinese Medicine Clinical Questionnaire” were designed to investigate the basic information of the patients， like the four diagnostic information （including symptoms， tongue， pulse） of traditional Chinese medicine （TCM）， and to count the frequency of the appearance of the four diagnostic information. Factor analysis and cluster analysis were employed to determine and statistically analyze the syndrome elements and patterns of HBV-ACLF patients at different stages. ResultsThere were 76 four diagnostic information from 1058 HBV-ACLF patients， and 53 four diagnostic information with a frequency of occurrence ≥ 5% were used as factor analysis entries， including 36 symptom information， 12 tongue information， and 5 pulse information. Four types of TCM patterns were identified in HBV-ACLF， which were liver-gallbladder damp-heat pattern， qi deficiency and blood stasis pattern， liver-kidney yin deficiency pattern， and spleen-kidney yang-deficiency pattern. In the early stage， heat （39.4%， 359/912） and dampness （27.5%， 251/912） were most common， and the pattern of the disease was dominated by liver-gallbladder damp-heat pattern （74.6%， 461/618）； in the middle stage， dampness （30.2%， 187/619） and blood stasis （20.7%， 128/619） were most common， and the patterns of the disease were dominated by liver-gallbladder damp-heat pattern （53.2%， 189/355）， and qi deficiency and blood stasis pattern （27.6%， 98/355）； and in the late stage， the pattern of the disease was dominated by qi deficiency （26.3%， 40/152） and yin deficiency （20.4%， 31/152）， and the patterns were dominated by qi deficiency and blood stasis pattern （36.5%， 31/85）， and liver-gallbladder damp-heat pattern （25.9%， 22/85）. ConclusionThere are significant differences in the distribution of syndrome elements and patterns at different stages of HBV-ACLF， presenting an overall trend of evolving patterns as "from excess to deficiency， transforming from excess to deficiency"， which is damp-heat → blood stasis → qi-blood yin-yang deficiency.

Objective To investigate the potential value of exosomes derived from rat ectoderm mesenchymal stem cells(EMSCs-exo)for repairing secondary spinal cord injury.Methods EMSCs-exo were obtained using ultracentrifugation from EMSCs isolated from rat nasal mucosa,identified by transmission electron microscope,nanoparticle tracking analysis(NTA),and Western blotting,and quantified using the BCA method.Neonatal rat microglia purified by differential attachment were induced with 100 μg/L lipopolysaccharide(LPS)and treated with 37.5 or 75 mg/L EMSCs-exo.PC12 cells were exposed to 400 μmol/L H2O2 and treated with EMSCs-exo at 37.5 or 75 mg/L.The protein and mRNA expressions of Arg1 and iNOS in the treated cells were determined with Western blotting and qRT-PCR,and the concentrations of IL-6,IL-10,and IGF-1 in the supernatants were measured with ELISA.The viability and apoptosis of PC12 cells were detected using CCK-8 assay and flow cytometry.Results The isolated rat EMSCs showed high expressions of nestin,CD44,CD105,and vimentin.The obtained EMSCs-exo had a typical cup-shaped structure under transmission electron microscope with an average particle size of 142 nm and positivity for CD63,CD81,and TSG101 but not vimentin.In LPS-treated microglia,EMSCs-exo treatment at 75 mg/L significantly increased Arg1 protein level and lowered iNOS protein expression(P<0.05).EMSCs-exo treatment at 75 mg/L,as compared with the lower concentration at 37.5 mg/L,more strongly increased Arg1 mRNA expression and IGF-1 and IL-10 production and decreased iNOS mRNA expression and IL-6 production in LPS-induced microglia,and more effectively promoted cell survival and decreased apoptosis rate of H2O2-induced PC12 cells(P<0.05).Conclusion EMSCs-exo at 75 mg/L can effectively reduce the proportion of M1 microglia and alleviate neuronal apoptosis under oxidative stress to promote neuronal survival,suggesting its potential in controlling secondary spinal cord injury.

Objective:To evaluate modified extended trochanteric osteotomy (ETO) applied in the revision of Vancouver B2/B3 periprosthetic femoral fractures (PFF).Methods:A retrospective study was conducted to analyze the 35 patients with Vancouver B2/B3 PFF who had been treated at Joint Disease Department Ⅱ, Zhengzhou Orthopedic Hospital from January 2012 to November 2020. There were 10 males and 15 females with an age of (74.3±7.8) years. The time from their primary replacement to revision was (120.3±28.6) months. By the Vancouver classification, 26 cases were type B2 and 9 ones type B3. The modified ETO was used in the revision surgery for all patients. The clinical efficacy was evaluated using Harris hip score, imaging evaluation was performed using the Beals and Tower criteria at the last follow-up, and complications were recorded.Results:The operation time for this cohort was (148±32) min and intraoperative bleeding (800±150) mL. All patients were followed up for (45.2±15.3) months. The Harris score increased significantly from preoperative (21.3±11.2) points to (86.2±5.2) points at the last follow-up ( P < 0.001). By the Beals and Tower evaluation, 9 cases were rated as excellent, 24 cases as good, and 2 as poor. All the fractures and sites of trochanteric osteotomy got healed after (4.4±2.8) months except for 1 case of nonunion. Prosthesis subsidence occurred in 3 cases, in 2 of which the subsidence stopped 6 months later and in only 1 of which revision was needed due to the subsidence. Upward block displacement of the greater trochanteric fracture occurred in 2 cases, but did not exceed 1 cm. One case of postoperative dislocation responded to manual reduction. Conclusion:In the revision of Vancouver B2/B3 PFF, the modified ETO can improve fracture healing, and reduce postoperative dislocations and complications, leading to satisfactory clinical efficacy.

Objective To investigate the potential value of exosomes derived from rat ectoderm mesenchymal stem cells(EMSCs-exo)for repairing secondary spinal cord injury.Methods EMSCs-exo were obtained using ultracentrifugation from EMSCs isolated from rat nasal mucosa,identified by transmission electron microscope,nanoparticle tracking analysis(NTA),and Western blotting,and quantified using the BCA method.Neonatal rat microglia purified by differential attachment were induced with 100 μg/L lipopolysaccharide(LPS)and treated with 37.5 or 75 mg/L EMSCs-exo.PC12 cells were exposed to 400 μmol/L H2O2 and treated with EMSCs-exo at 37.5 or 75 mg/L.The protein and mRNA expressions of Arg1 and iNOS in the treated cells were determined with Western blotting and qRT-PCR,and the concentrations of IL-6,IL-10,and IGF-1 in the supernatants were measured with ELISA.The viability and apoptosis of PC12 cells were detected using CCK-8 assay and flow cytometry.Results The isolated rat EMSCs showed high expressions of nestin,CD44,CD105,and vimentin.The obtained EMSCs-exo had a typical cup-shaped structure under transmission electron microscope with an average particle size of 142 nm and positivity for CD63,CD81,and TSG101 but not vimentin.In LPS-treated microglia,EMSCs-exo treatment at 75 mg/L significantly increased Arg1 protein level and lowered iNOS protein expression(P<0.05).EMSCs-exo treatment at 75 mg/L,as compared with the lower concentration at 37.5 mg/L,more strongly increased Arg1 mRNA expression and IGF-1 and IL-10 production and decreased iNOS mRNA expression and IL-6 production in LPS-induced microglia,and more effectively promoted cell survival and decreased apoptosis rate of H2O2-induced PC12 cells(P<0.05).Conclusion EMSCs-exo at 75 mg/L can effectively reduce the proportion of M1 microglia and alleviate neuronal apoptosis under oxidative stress to promote neuronal survival,suggesting its potential in controlling secondary spinal cord injury.

Objective:To explore the key targets and mechanism of Bielong Ruangan decoction in the treatment of liver cancer based on network pharmacology and molecular docking.Methods:Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database, PubChem database and PharmMapper database were used to search and screen the chemical components and related targets of Bielong Ruangan decoction and the targets of liver cancer diseases. The network diagram of " Bielong Ruangan decoction-traditional Chinese medicine-active ingredient-predicted target-disease" was constructed; Protein-protein interaction (PPI) network were analyzed through String database; gene ontology (GO) enrichment analysis was performed through WebGestalt database; Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was carried out through KEGG Orthology Based Annotation System (KOBAS) database; Molecular docking of the active components and core target proteins of Bielong Ruangan decoction was carried out by using PyMOL, Auto DockVina and other software.Results:Bielong Ruangan decoction had 67 active components, 154 liver cancer targets and 244 pathways. According to the analysis of network pharmacology, Bielong Ruangan decoction may play an anti-cancer role through key targets such as epidermal growth factor receptor (EGFR), mitogen activated protein kinase 1 (MAPK1), estrogen receptor 1 (ESR1), MAPK8, serine threonine protein kinase 1 (AKT1), MAPK14, cysteine protease 3 (CASP3), cyclin-dependent kinase 2 (CDK2), bone morphogenetic protein 2 (BMP2), aldose reductase (AKR1B1) and other key targets. KEGG enrichment analysis showed that the treatment of liver cancer by Bielong Ruangan decoction involved the regulation of vascular endothelial growth factor (VEGF) signaling pathway, tumor necrosis factor (TNF) signaling pathway, thyroid hormone signaling pathway, T cell receptor signaling pathway and other pathways. The results of molecular docking showed that the binding energy of all compounds to protein was less than -5.6 kcal/mol, indicating that each compound and each protein could bind well.Conclusions:Bielong Ruangan decoction participates in the treatment of liver cancer through " multi-component, multi-target and multi-channel" ways, and plays an anti-cancer role mainly by regulating the proliferation and invasion of tumor cells and tumor inflammatory microenvironment.

Objective To study biomechanical effects of cannulated screws at different fixation angles on posterior malleolus fracture based on finite element method, so as to determine the best fixation method of cannulatedscrew. Methods The finite element model of ankle joint, including tibia, fibula, astragalus, corresponding cartilage and ligaments was reconstructed using CT images, and 1 / 2 posterior malleolus fracture model was established on the basis of verifying its validity. The biomechanical effects of cannulated screw fixation on posterior malleolus fracture fixation model were analyzed. Results Compared with 0°,5°,10°,20° fixation model, the 15° fixation model had the smallest displacement. The screw stress of 15° fixation model was lower than that of 5°, 10°, 20° fixation model, and higher than that of 0° fixation model. But when the screw fixation angle was 0°, the peak contact pressure of ankle joint was much larger than that of normal ankle joint, which was easy to cause traumatic osteoarthritis. Conclusions Cannulated screw is safe and effective for treating posterior malleolus fracture which is less than 1 / 2 fragment size. The displacement and stress of the model are different at different fixation angles of screws. When the fixation angle of screw is 15°, the biomechanical stability is the best, which can be used to guide clinical operation.

Liver fibrosis is the common result of various chronic liver injuries and can progress to liver cirrhosis and even liver cancer, and at present, there is still no effective means to reverse liver fibrosis. The transformation of activated hepatic stellate cells (HSC) in perisinusoidal space into myofibroblasts and the secretion of collagen are a central event in the process of liver fibrosis. NLRP3 inflammasome can be activated by various injury stimuli and mediate inflammatory response and pyroptosis. Recent studies have found that the activation of NLRP3 inflammasome is closely associated with HSC activation. This article introduces the activation of NLRP3 inflammasome in different pathways in HSC under various pathological factors and role of NLRP3 inflammasome in the formation of extracellular inflammatory microenvironment, thereby mediating HSC activation and playing an important role in promoting liver fibrosis.