Objective : To establish an interleukin-1β (Il-1β) induced inflammatory model of rat articular chondro- cytes (ACs) , and to investigate the relationship between the expression of lysine acetyltransferase 7 (KAT7) under inflammatory stimulation and the senescence of ACs. Methods: Primary ACs were obtained by digestion of rat knee cartilage with collagenase type Ⅱ and identified. The inflammatory model of ACs was induced by IL-1β . KAT7 was over-expressed or knocked down in ACs by adeno-associated virus infection or small interfering RNA transfection , respectively. A negative control group was set up. Transwell assay was used to detect cell migration ability. Senes- cent cells were stained with senescence-associated β-galactosidase (SA-β-Gal) . Western blot ( WB) was used to detect the protein expression levels of KAT7 , collagen type II (Col Ⅱ ) , matrix metalloproteinase 13 (MMP13) , tumor protein p53 (p53) and cyclin-dependent kinase inhibitor 1A (p21) . The cells of negative control group and KAT7 over-expression group were performed for RNA sequencing , and WB was used to verify the related signaling pathways obtained by Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis. Results: Compared with the control group , the SA-β-Gal staining was enhanced , the protein expression of Col Ⅱ decreased , the pro- tein expression of MMP13 and p53 increased , the cell migration ability decreased , and the expression of KAT7 also increased in the ACs of rats after IL-1β stimulation. Compared with the negative control group , the SA-β-Gal stai- ning was enhanced , the protein expression of Col Ⅱ decreased , the protein expression of MMP13 , p53 and p21 in- creased , and the cell migration ability decreased in the KAT7 over-expression group. Compared with the negative control group , the SA-β-Gal staining was weakened , the protein expression of Col Ⅱ increased , the protein expres- sion of MMP13 , p53 and p21 decreased , and the cell migration ability was enhanced in the KAT7 knockdown inflammatory model of ACs. KEGG enrichment analysis showed that phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway was activated. Compared with the negative control group , the relative protein ex⁃pression levels of phosphorylated protein kinase B (p⁃AKT)/AKT and phosphorylated mammalian target of rapamy⁃cin (p⁃mTOR)/mTOR in KAT7 over⁃expression group increased. The relative protein expression levels of p ⁃AKT/AKT and p ⁃mTOR/mTOR in KAT7 knockdown cells decreased. Conclusion Rat ACs with high expression of KAT7 exhibit senescence and osteoarthritis phenotype , and the mechanism may be related to the activation of PI3K/AKT/mTOR signaling pathway by KAT7.

Objective To evaluate the preservation effect of normothermic mechanical perfusion with red blood cells from humanized genetically modified pig on severed human limbs.Methods Severed human limbs were perfused with red blood cells from humanized genetically modified pigs for 6 h.Perfusion solution was taken every hour to measure the oxygen partial pressure,Na+,K+,Ca2+,pH value,glucose,lactic acid and creatine kinase levels.Superficial flexor muscle was sampled to detect the changes of tumor necrosis factor(TNF)-α,interleukin(IL)-2 and IL-1 levels.At 0 and 6 h after perfusion,the superficial flexor muscles of the forearm were taken for pathological examination.Intercellular space and glycogen consumption of skeletal muscles were observed.An appropriate amount of forearm vessels was collected every 2 h to detect the apoptosis of vascular endothelial cells.X-ray angiography was performed before perfusion and 6 h after perfusion to observe the filling degree of finger-tip peripheral vessels.Results The oxygen partial pressure was observed in the normal range throughout the perfusion.Na+concentration peaked at 1 h,reaching 138.7 mmol/L,and then fluctuated within the normal range.K+level peaked at 2 h up to 6.08 mmol/L,then decreased and fluctuated within the normal range.Ca2+concentration reached the peak at 4 h,up to 1.03 mmol/L.Glucose level was gradually decreased at the beginning of perfusion,reaching the lowest value of 17.7 mmol/L at 2 h after perfusion,and then maintained a dynamic balance.The pH value was decreased to 7.28 at 6 h after perfusion.The lactic acid level was increased to 9.6 mmol/L at 1 h after perfusion,and then gradually decreased.The creatine kinase level was increased at the start of perfusion,reached the peak at 2 h up to 20 030 U/L,then decreased and remained stable at the end of perfusion.At the end of perfusion,the morphology of muscle fibers was normal,the gap among muscle fibers was expanded slightly,and the glycogen of skeletal muscles was not significantly accumulated.At 0 h perfusion,the number of apoptotic cells in vascular endothelial cells was large,which was declined at 6 h perfusion.Evident vascular filling was observed at 0 h,and the filling degree of some finger-tip vessels was decreased at 6 h.Conclusions Normothermic mechanical perfusion of severed human limbs with red blood cells from humanized genetically modified pigs may continuously and stably supply energy and oxygen,adjust the ion pH balance of perfusion solution,maintain normal cellular metabolism and exerts certain protective effect upon severed human limbs.

Although blood banks based on human blood can provide blood transfusions for the wounded timely and effec-tively,scientific research has never given up on finding new blood sources due to the restrictions of human blood sources.With the application of transgenic technology and the successful breeding of gene-edited pigs,gene-edited pig blood as a po-tential source of clinical transfusion has attracted wide attention.Now there are preclinical studies showing the feasibility of transfusing gene-edited pig red blood cells into primates.This paper discusses the related research and future development of xenogeneic transfusion of porcine red blood cells by gene editing.

Objective To investigate the differences and the immunocompatibility of wild-type (WT), four-gene modified (TKO/hCD55) and six-gene modified (TKO/hCD55/hCD46/hTBM) pig erythrocytes with human serum. Methods The blood samples were collected from 20 volunteers with different blood groups. WT, TKO/hCD55, TKO/hCD55/hCD46/hTBM pig erythrocytes, ABO-compatible (ABO-C) and ABO-incompatible (ABO-I) human erythrocytes were exposed to human serum of different blood groups, respectively. The blood agglutination and antigen-antibody binding levels (IgG, IgM) and complement-dependent cytotoxicity were detected. The immunocompatibility of two types of genetically modified pig erythrocytes with human serum was evaluated. Results No significant blood agglutination was observed in the ABO-C group. The blood agglutination levels in the WT and ABO-I groups were higher than those in the TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups (all P<0.001). The level of erythrocyte lysis in the WT group was higher than those in the ABO-C, TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups. The level of erythrocyte lysis in the ABO-I group was higher than those in the TKO/hCD55 and TKO/hCD55/hCD46/hTBM groups (both P<0.01). The pig erythrocyte binding level with IgM and IgG in the TKO/hCD55 group was lower than those in the WT and ABO-I groups. The pig erythrocyte binding level with IgG and IgM in the TKO/hCD55/hCD46/hTBM group was lower than that in the WT group and pig erythrocyte binding level with IgG was lower than that in the ABO-I group (all P<0.05). Conclusions The immunocompatibility of genetically modified pig erythrocytes is better than that of wild-type pigs and close to that of ABO-C pigs. Humanized pig erythrocytes may be considered as a blood source when blood sources are extremely scarce.

Inflammatory bowel disease(IBD)is a serious disorder,and exploration of active compounds to treat it is necessary.An acidic polysaccharide named SUSP-4 was purified from Selaginella uncinata(Desv.)Spring,which contained galacturonic acid,galactose,xylose,arabinose,and rhamnose with the main chain structure of →4)-α-D-GalAp-(1 → and →6)-β-D-Galp-(1 → and the branched structure of →5)-α-L-Araf-(1 →.Animal experiments showed that compared with Model group,SUSP-4 significantly improved body weight status,disease activity index(DAI),colonic shortening,and histopathological damage,and elevated occludin and zonula occludens protein 1(ZO-1)expression in mice induced by dextran sulfate sodium salt(DSS).16S ribosomal RNA(rRNA)sequencing indicated that SUSP-4 markedly downregulated the level of Akkermansia and Alistipes.Metabolomics results confirmed that SUSP-4 obviously elevated thiamine levels compared with Model mice by adjusting thiamine metabolism,which was further confirmed by a targeted metabolism study.Fecal transplantation experiments showed that SUSP-4 exerted an anti-IBD effect by altering the intestinal flora in mice.A mechanistic study showed that SUSP-4 markedly inhibited macrophage activation by decreasing the levels of phospho-nuclear factor kappa-B(p-NF-κB)and cyclooxygenase-2(COX-2)and elevating NF-E2-related factor 2(Nrf2)levels compared with Model group.In conclusion,SUSP-4 affected thiamine metabolism by regulating Akker-mania and inhibited macrophage activation to adjust NF-κB/Nrf2/COX-2-mediated inflammation and oxidative stress against IBD.This is the first time that plant polysaccharides have been shown to affect thiamine metabolism against IBD,showing great potential for in-depth research and development applications.

Lysobacter harbors a plethora of cryptic biosynthetic gene clusters (BGCs), albeit only a limited number have been analyzed to date. In this study, we described the activation of a cryptic polyketide synthase (PKS)/nonribosomal peptide synthetase (NRPS) gene cluster (lsh) in Lysobacter sp. DSM 3655 through promoter engineering and heterologous expression in Streptomyces sp. S001. As a result of this methodology, we were able to isolate two novel linear lipopeptides, lysohexaenetides A (1) and B (2), from the recombinant strain S001-lsh. Furthermore, we proposed the biosynthetic pathway for lysohexaenetides and identified LshA as another example of entirely iterative bacterial PKSs. This study highlights the potential of heterologous expression systems in uncovering cryptic biosynthetic pathways in Lysobacter genomes, particularly in the absence of genetic manipulation tools.
Lysobacter/metabolism* ; Streptomyces/metabolism* ; Lipopeptides/metabolism* ; Polyketide Synthases/genetics* ; Multigene Family

Minute pulmonary meningothelial-like nodules (MPMNs) are benign small lesions in the lungs, with similar pathological characteristics to the meningeal epithelium. MPMNs have similar imaging manifestations to malignant tumors, which can lead to misdiagnosis in clinical practice. There is no consensus on the pathogenesis of MPMNs, with some suggest that MPMNs derive from reactive proliferation, while others suggest that MPMNs share a common origin and molecular mechanism with meningiomas in the central nervous system. Understanding the characteristics of MPMNs and studying their pathogenesis will help improve the understanding and diagnosis of MPMNs. In this article, we reviewed the clinical, pathological, imaging characteristics, differential diagnosis and pathogenesis of MPMNs. We also analyze the existing research advances regarding the pathogenesis and propose prospects for further research.
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It is necessary to explore potent therapeutic agents via regulating gut microbiota and metabolism to combat Parkinson's disease(PD).Dioscin,a bioactive steroidal saponin,shows various activities.How-ever,its effects and mechanisms against PD are limited.In this study,dioscin dramatically alleviated neuroinflammation and oxidative stress,and restored the disorders of mice induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP).16 S rDNA sequencing assay demonstrated that dioscin reversed MPTP-induced gut dysbiosis to decrease Firmicutes-to-Bacteroidetes ratio and the abundances of Enterococcus,Streptococcus,Bacteroides and Lactobacillus genera,which further inhibited bile salt hy-drolase(BSH)activity and blocked bile acid(BA)deconjugation.Fecal microbiome transplantation test showed that the anti-PD effect of dioscin was gut microbiota-dependent.In addition,non-targeted fecal metabolomics assays revealed many differential metabolites in adjusting steroid biosynthesis and pri-mary bile acid biosynthesis.Moreover,targeted bile acid metabolomics assay indicated that dioscin increased the levels of ursodeoxycholic acid,tauroursodeoxycholic acid,taurodeoxycholic acid and β-muricholic acid in feces and serum.In addition,ursodeoxycholic acid administration markedly improved the protective effects of dioscin against PD in mice.Mechanistic test indicated that dioscin significantly up-regulated the levels of takeda G protein-coupled receptor 5(TGR5),glucagon-like peptide-1 receptor(GLP-1R),GLP-1,superoxide dismutase(SOD),and down-regulated NADPH oxidases 2(NOX2)and nu-clear factor-kappaB(NF-κB)levels.Our data indicated that dioscin ameliorated PD phenotype by restoring gut dysbiosis and regulating bile acid-mediated oxidative stress and neuroinflammation via targeting GLP-1 signal in MPTP-induced PD mice,suggesting that the compound should be considered as a prebiotic agent to treat PD in the future.

Objective:To investigate the application and effect of the virtual reality (VR) combined with the augmented reality (AR) integrated teaching system in stomatology general medical education of clinical medicine students.Methods:A total of 160 undergraduates from the five-year clinical medicine Batch 2015 of Naval Medical University were randomly divided into VR+AR group and traditional group, with 80 students in each group. A comparative analysis was made on the previous and teaching achievements of the two groups of students, and a questionnaire survey was conducted after the completion of the class. Epidata 3.0 was used to input questionnaire data, and SPSS 23.0 software was used to carry out t test, chi-square test and Fisher precision test. Results:There was no statistical difference in written test scores between the VR+AR group and the traditional group [(52.65±3.76) vs. (51.90±3.46), P=0.516], but the VR+AR group was significantly higher than the traditional group in case analysis scores [(35.85±2.56) vs. (31.40±2.96), P < 0.001] and overall performance [(88.50±4.95) vs. (83.30±4.86), P= 0.002]. The questionnaire survey results showed that the scores of "teaching mode" [(92.30±6.90) vs. (85.20±7.30), P<0.001], "teaching method" [(91.70±5.90) vs. (86.00±6.70), P=0.012] and "teaching improvement" [(90.70± 8.70) vs. (82.30±8.40), P<0.001] in VR + AR group were significantly higher than those in the traditional teaching group. Conclusion:The VR combined with AR integrated teaching system can significantly improve teaching performance and teaching quality, and is convenient for teaching demonstrations and simulation operations in small oral spaces, and is especially suitable for oral general medical education for clinical medicine.

Radiotherapy plays an important role in the treatment of cervical cancer. The radiosensitivity of cervical cancer is closely related to genes, RNA regulation, tumor microenvironment, drugs and other factors. Recently, many studies have been conducted to continuously explore the mechanisms of these factors in radiotherapy sensitization, and progress has been made in radiotherapy sensitization of cervical cancer at basic or clinical level.