This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

Objective:To investigate the effect of oleanolic acid(OA)on inflammatory injury of pancreatic acinar cells in-duced by lipopolysaccharide(LPS)by regulating stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor 4(CXCR4)signal axis.Methods:Rat pancreatic acinar cells AR42J were treated with 5,10,20 and 40 μmol/L OA,and the cell viability was detected using CCK-8 method to determine the optimal dosage for subsequent experimental OA treatment;AR42J cells were randomly divided into control group(NC),LPS group(10 mg/L LPS),OA low-dose group(OA-L group,10 mg/L LPS+5 μmol/L OA),OA medium dose group(OA-M group,10 mg/L LPS+10 μmol/L OA),OA high-dose group(OA-H group,10 mg/L LPS+20 μmol/L OA),Rr-SDF-1 activator(SDF-1)group(10 mg/L LPS+20 ng/ml Rr-SDF-1)and OA-H+Rr-SDF-1 group(10 mg/L LPS+20 μmol/L OA+20 ng/ml Rr-SDF-1).CCK-8 method and EdU staining were applied to detect proliferation of AR42J cells;flow cytometry was applied to detect apoptosis of AR42J cells;activity of superoxide dismutase(SOD)and content of malondialdehyde(MDA)in cell supernatant were detected by spectrophotometry;ELISA was applied to detect levels of IL-6 and TNF-α in cell supernatant;Western blot was applied to detect expressions of CyclinD1,Bcl-2 associated X protein(Bax),SDF-1 and CXCR4 proteins in cells.Results:5,10 and 20 μmol/L OA were selected as the low,medium and high doses for subsequent treatment of AR42J cells;compared with NC group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in LPS group decreased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions increased(P<0.05);compared with LPS group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in OA-L group,OA-M group and OA-H group increased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions reduced,the change trends of corre-sponding indicators in Rr-SDF-1 group was opposite to the above(P<0.05);compared with OA-H group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in OA-H+Rr-SDF-1 group decreased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions increased(P<0.05).Conclusion:OA may alleviate LPS induced inflam-matory damage to pancreatic acinar cells in rats by inhibiting the SDF-1/CXCR4 pathway.

Acute lung injury (ALI) is a severe disease caused by viral infection that triggers an uncontrolled inflammatory response. This study investigated the capacity of jasurolignoside (JO), a natural compound, to bind to Toll-like receptor 4 (TLR4) and treat ALI. The anti-inflammatory properties of JO were evaluated in vitro through Western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence staining, and co-immunoprecipitation. The investigation utilized a lipopolysaccharide (LPS)-induced ALI animal model to examine the therapeutic efficacy and mechanism of JO in vivo. JO attenuated inflammatory symptoms in infected cells and tissues by modulating the NOD-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome and the nuclear factor κB (NF-κB)/mitogen-activated protein kinase (MAPK) pathway. Molecular docking simulations revealed JO binding to TLR4 active sites, confirmed by cellular thermal shift assay. Surface plasmon resonance (SPR) demonstrated direct interaction between JO and TLR4 with a Kd value of 35.1 μmol·L^-1. Moreover, JO inhibited tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 secretion and reduced leukocyte, neutrophil, lymphocyte, and macrophage infiltration in ALI-affected mice. JO also enhanced lung function and reduced ALI-related mortality. Immunohistochemical staining demonstrated JO's ability to suppress TLR4 expression in ALI-affected mouse lung tissue. This study establishes that JO can bind to TLR4 and effectively treat ALI, indicating its potential as a therapeutic agent for clinical applications.
Toll-Like Receptor 4/chemistry* ; Animals ; Acute Lung Injury/chemically induced* ; Mice ; Humans ; Ilex/chemistry* ; Molecular Docking Simulation ; Male ; NF-kappa B/immunology* ; Mice, Inbred C57BL ; NLR Family, Pyrin Domain-Containing 3 Protein/immunology* ; Tumor Necrosis Factor-alpha/genetics* ; Interleukin-1beta/genetics* ; RAW 264.7 Cells ; Disease Models, Animal

Objective To modify the dosage form of Guoganglong Sugar-Coated Tablets,and to investigate the chemical equivalence and pharmacodynamic equivalence between the new and old dosage forms of Guoganglong Tablets.Methods The preparation technology was screened by single-factor exploration with the indexes of hardness and dispersion uniformity,the quality standard was established by thin layer chromatography identification,high performance liquid chromatography(HPLC)content determination and charactertistics chromatograms,the constituents absorbed into blood were analyzed by ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry(UHPLC-Q-TOF-MS),and the pharmacodynamics was evaluated by anti-inflammatory experiment and analgesic experiment in mice model with inflammatory pain.Results The molding process of Guoganglong Dispersible Tablets was determined.A thin layer chromatographic identification method was established.A method for detecting the content of Guoganglong Tablets and the charactertistic chromatograms was established by HPLC,and a total of 15 common peaks were identified,with the similarity of the new-old dosage forms being greater than 0.9.A total of 12 constituents absorbed into blood were identified.Guoganglong Tablets could alleviate swelling degree of toes in mice with inflammatory pain,reduce the levels of interleukin 6(IL-6)in serum,improve spleen index,and increase the thermal pain threshold and acetic acid twisting frequency in mice.Conclusion The prescription process of Guoganglong Dispersible Tablets is stable,the quality standard is feasible,the chemical composition and pharmacological actions between the new and old dosage forms are basically the same,and in terms of certain indexes,Dispersible Tablets of Guoganglongare superior to Sugar-Coated Tablets.

Objective Through in vitro experiments,biomechanical data of the transtibial pullout suture(TPS),tendon reconstruction(TR),and tendon reconstruction with suture augmentation(TRS)were collected,so as to evaluate the biomechanical effectiveness of tendon reconstruction for repairing medial meniscus posterior root tear(MMPRT).Methods Eighteen porcine knee joint models were divided into TPS,TR,and TRS groups.Sutures were used to fix the meniscal root in TPS group.Tendons were passed through an incision at the meniscal root in TR group.Tendons were passed through an incision at the meniscal root and secured at tendon-meniscus contact area with additional sutures in TRS group.The sutures and tendons were pulled out through tibial tunnels and fixed at the anteromedial tibia.All groups underwent failure load tests,and ultimate failure load,displacement at failure load,load at clinical failure,stiffness,and failure modes of the samples were recorded.Results The maximum failure load in TPS group was significantly higher than that in TR group(P＜0.05),but there was no significant difference between TPS group and TRS group(P＞0.05).The maximum failure load in TRS group was significantly higher than that in TR group(P＜0.05).The displacement under failure load in TR group and TRS group was significantly lower than that in TPS group(P＜0.05),but there was no significant difference between TR group and TRS group(P＞0.05).There were no significant differences in the load under clinical failure among the 3 groups(P＞0.05).The stiffness of TRS group was significantly greater than that of TPS group(P＜0.05),but no significant difference was observed between TR group and TPS group,as well as between TR group and TRS group(P＞0.05).All failures were caused by suture or tendon cutting through the meniscus.Conclusions The tendon reconstruction techniques is superior to the TPS in terms of failure displacement and stiffness,while the TRS further enhances the stability of the repair.

Objective:To investigate the effect of oleanolic acid(OA)on inflammatory injury of pancreatic acinar cells in-duced by lipopolysaccharide(LPS)by regulating stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor 4(CXCR4)signal axis.Methods:Rat pancreatic acinar cells AR42J were treated with 5,10,20 and 40 μmol/L OA,and the cell viability was detected using CCK-8 method to determine the optimal dosage for subsequent experimental OA treatment;AR42J cells were randomly divided into control group(NC),LPS group(10 mg/L LPS),OA low-dose group(OA-L group,10 mg/L LPS+5 μmol/L OA),OA medium dose group(OA-M group,10 mg/L LPS+10 μmol/L OA),OA high-dose group(OA-H group,10 mg/L LPS+20 μmol/L OA),Rr-SDF-1 activator(SDF-1)group(10 mg/L LPS+20 ng/ml Rr-SDF-1)and OA-H+Rr-SDF-1 group(10 mg/L LPS+20 μmol/L OA+20 ng/ml Rr-SDF-1).CCK-8 method and EdU staining were applied to detect proliferation of AR42J cells;flow cytometry was applied to detect apoptosis of AR42J cells;activity of superoxide dismutase(SOD)and content of malondialdehyde(MDA)in cell supernatant were detected by spectrophotometry;ELISA was applied to detect levels of IL-6 and TNF-α in cell supernatant;Western blot was applied to detect expressions of CyclinD1,Bcl-2 associated X protein(Bax),SDF-1 and CXCR4 proteins in cells.Results:5,10 and 20 μmol/L OA were selected as the low,medium and high doses for subsequent treatment of AR42J cells;compared with NC group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in LPS group decreased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions increased(P<0.05);compared with LPS group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in OA-L group,OA-M group and OA-H group increased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions reduced,the change trends of corre-sponding indicators in Rr-SDF-1 group was opposite to the above(P<0.05);compared with OA-H group,A450 value,EdU positive cell rate,SOD activity,and CyclinD1 protein expression in OA-H+Rr-SDF-1 group decreased,while apoptosis rate,MDA content,IL-6,TNF-α levels,Bax,SDF-1 and CXCR4 protein expressions increased(P<0.05).Conclusion:OA may alleviate LPS induced inflam-matory damage to pancreatic acinar cells in rats by inhibiting the SDF-1/CXCR4 pathway.

Objective Through in vitro experiments,biomechanical data of the transtibial pullout suture(TPS),tendon reconstruction(TR),and tendon reconstruction with suture augmentation(TRS)were collected,so as to evaluate the biomechanical effectiveness of tendon reconstruction for repairing medial meniscus posterior root tear(MMPRT).Methods Eighteen porcine knee joint models were divided into TPS,TR,and TRS groups.Sutures were used to fix the meniscal root in TPS group.Tendons were passed through an incision at the meniscal root in TR group.Tendons were passed through an incision at the meniscal root and secured at tendon-meniscus contact area with additional sutures in TRS group.The sutures and tendons were pulled out through tibial tunnels and fixed at the anteromedial tibia.All groups underwent failure load tests,and ultimate failure load,displacement at failure load,load at clinical failure,stiffness,and failure modes of the samples were recorded.Results The maximum failure load in TPS group was significantly higher than that in TR group(P＜0.05),but there was no significant difference between TPS group and TRS group(P＞0.05).The maximum failure load in TRS group was significantly higher than that in TR group(P＜0.05).The displacement under failure load in TR group and TRS group was significantly lower than that in TPS group(P＜0.05),but there was no significant difference between TR group and TRS group(P＞0.05).There were no significant differences in the load under clinical failure among the 3 groups(P＞0.05).The stiffness of TRS group was significantly greater than that of TPS group(P＜0.05),but no significant difference was observed between TR group and TPS group,as well as between TR group and TRS group(P＞0.05).All failures were caused by suture or tendon cutting through the meniscus.Conclusions The tendon reconstruction techniques is superior to the TPS in terms of failure displacement and stiffness,while the TRS further enhances the stability of the repair.

Objective:To investigate impacts of usnic acid(UA)on malignant behavior of gastric cancer cells by regulating the chemokine(C-C motif)ligand 2(CCL2)-CCL2 receptor(CCR2)signal axis.Methods:SGC-7901 cells,a well growing human gastric cancer cell line,were treated with different concentrations of UA,which were grouped into low concentration(UA-L)group(62.5 μmol/L UA),medium concentration(UA-M)group(125 μmol/L UA)and high concentration(UA-H)group(250 μmol/L UA);meantime,the cells were transfected with CCL2 overexpression vector(pc DNA3.1 CCL2),empty vector(pc DNA3.1),silenced CCL2(si CCL2)and negative control(si control),and SGC-7901 cells were treated with 250 μmol/L UA,labeled as UA-H+pc DNA3.1 CCL2 group,UA-H+pc DNA3.1 group,UA-H+si control group and UA-H+si CCL2 group,another untreated SGC-7901 cells were taken as the control group.Flow cytometry,MTT and qRT-PCR were applied to detect cell apoptosis,proliferation,and expres-sion levels of CCL2 and CCR2 mRNA;Western blot was applied to detect expression levels of PD-L1,apoptotic protein(Bax),proli-ferative protein(CyclinD1,CCL2,CCR2)and immune escape related protein(B7H1);after co-culturing with CD8+T cells isolated and cultured in vitro,ELISA was applied to detect levels of IL-4,IFN-γ and IL-10 in the supernatant.Gastric cancer cells in each group were co-cultured with activated peripheral blood mononuclear cell(PBMC)1∶1 for 72 hours,and the sensitivity of gastric can-cer cells in each group to T-cell-mediated killing was compared.Results:Compared with control group,cell proliferation rate,IL-10 level,CyclinD1,PD-L1,CCL2,CCR2 and B7H1 protein and mRNA expressions,cell counts after co-culturing with activated PBMC 1∶1 for 72 hours in UA-L group,UA-M group and UA-H group were obviously reduced,while apoptosis rate,IL-4 and IFN-γ levels,Bax protein expression were obviously increased(P<0.05);compared with UA-H+pc DNA3.1 group,cell proliferation rate,IL-10 level,CyclinD1,PD-L1,CCL2,CCR2 protein and mRNA expressions,cell counts after co-culturing with activated PBMC 1∶1 for 72 hours in UA-H+pc DNA3.1 CCL2 group were obviously increased,while apoptosis rate,IL-4 and IFN-γ levels,and Bax protein ex-pression were obviously reduced(P<0.05);compared with UA-H+si control group,cell proliferation rate,IL-10 level,CyclinD1,PD-L1,CCL2,CCR2 and B7H1 protein and mRNA expressions,cell counts after co-culturing with activated PBMC 1∶1 for 72 hours in UA-H+si CCL2 group were obviously reduced,while apoptosis rate,IL-4 and IFN-γ levels and Bax protein expression were obviously increased(P<0.05).Conclusion:UA can inhibit gastric cancer cells proliferation,immune escape,and induce apoptosis,which may be related to the inhibition of the CCL2-CCR2 signaling axis.

Seven compounds were isolated from Onychium japonicum by macroporous resin, silica gel, ODS, Sephadex LH-20 column chromatography and semi-preparative HPLC. Their structures were identified by NMR, MS and other spectroscopic methods as onychone A (1), quercetin (2), quercetin-3-O-α-L-rhamnoside (3), kaempferol-7-O-β-D-glucopyranoside (4), kaempferol-3-O-α-L-rhamnopyranoside (5), (-)-prunin (6), and norathyriol (7). Compound 1 is a novel macrocyclic flavonoid, and all the others are reported from this plant for the first time. In vitro cytotoxic activities of compounds 1-7 were evaluated by MTS testing with five cancer cell lines. Compound 7 exhibited weak cytotoxicity against tumor cell lines A549, SMMC-7721, and SW480.