Autophagy of bovine mammary epithelial cell induced by intracellular Staphylococcus aureus

Na Geng,Kangping Liu,Jianwei Lu,Yuliang Xu,Xiaozhou Wang,Run Wang,Jianzhu Liu,Yongxia Liu,Bo Han 한국미생물학회 2020 The journal of microbiology Vol.58 No.4

Bovine mastitis is a common disease in the dairy industry that causes great economic losses. As the primary pathogen of contagious mastitis, Staphylococcus aureus (S. aureus) can invade bovine mammary epithelial cells, thus evading immune defenses and resulting in persistent infection. Recently, autophagy has been considered an important mechanism for host cells to clear intracellular pathogens. In the current study, autophagy caused by S. aureus was detected, and the correlation between autophagy and intracellular S. aureus survival was assessed. First, a model of intracellular S. aureus infection was established. Then, the autophagy of MAC-T cells was evaluated by confocal microscopy and western blot. Moreover, the activation of the PI3K-Akt-mTOR and ERK1/2 signaling pathways was determined by western blot. Finally, the relationship between intracellular bacteria and autophagy was analyzed by using autophagy regulators (3-methyladenine [3-MA], rapamycin [Rapa] and chloroquine [CQ]). The results showed that S. aureus caused obvious induction of autophagosome formation, transformation of LC3I/II, and degradation of p62/SQSTM1 in MAC-T cells; furthermore, the PI3K-Akt-mTOR and ERK1/2 signaling pathways were activated. The number of intracellular S. aureus increased significantly with autophagy activation by rapamycin, whereas the number decreased when the autophagy flux was inhibited by chloroquine. Therefore, this study indicated that intracellular S. aureus can induce autophagy and utilize it to survive in bovine mammary epithelial cells.

Study on Electrical Aging Characteristics of Fiber Sheath Materials in Power Transformer Oil

Lu Sun,Xiaozhou Fan,Shuo Jiang,Bowen Wang,Yun-Peng Liu,Shuguo Gao,Lingming Meng 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.5

Experimental Study on Static and Fatigue Performance of Uplift-Restricted and Slip-Permitted Connectors

Xian Liang,Xiaozhou Liu,Nuocheng Tian 한국강구조학회 2023 International Journal of Steel Structures Vol.23 No.1

The uplift-restricted and slip-permitted (Referred to as “URSP”) connector is a new type of structure applied in the negative bending moment region of continuous steel–concrete composite beams. The application of the URSP connector can effectively releases the shear stress between the interface of composite beam, enhances the interface slip capacity, and then improves the crack resistance of concrete slab. In order to investigate the static and fatigue performance of the URSP connector, static and cyclic loading tests were carried out on two and six tensile specimens respectively. Through the experimental study, the following conclusions are obtained: (1) The static failure mode of the URSP connector is connector tensile yielding, the fatigue failure modes include tensile yield of connector and punching shear failure of concrete. (2) The fatigue stress amplitude played a decisive role in the fatigue life of the URSP connector, the fatigue life decreased sharply with the increase of the stress amplitude. Finally, the failure mechanism and S–N curve of URSP are obtained.

Sustained-released mixture of vascular endothelial growth factor 165 and fibrin glue strengthens healing of ileal anastomoses in a rabbit model with intraperitoneal infection

Zhanwu Li,Wenjun Wang,Xiaozhou Wang,Lei Jiang,Fengyi Wang,Qiang Liu 대한외과학회 2017 Annals of Surgical Treatment and Research(ASRT) Vol.93 No.3

Purpose: To investigate the effects of a sustained-released mixture of vascular endothelial growth factor 165 (VEGF165) and fibrin glue (FG) local administration on postoperative rabbit ileal anastomoses. Methods: One hundred twenty-eight male and female New Zealand white rabbits underwent intraperitoneal infection subsequent ileal anastomosis surgery were divided randomly into 4 groups, including 32 animals in each, applied with saline solution, FG, rhVEGF165 and a mixture of rhVEGF165 with FG (VEGF + FG) on the anastomoses, respectively. The incidences of anastomotic leakage were observed. Histopathological examination for inflammatory infiltration, fibroblast proliferation, and capillary vascular proliferation were performed. Then, bursting pressure and hydroxyproline concentrations were assessed in anastomoses sits on postoperative days 3, 5, 7, and 14. Results: Rabbits in VEGF + FG group had the lowest incidence of leakage (P < 0.05). Histological evaluations revealed that granulation tissue was formed on days 5 after anastomosis; fibroblast proliferation and capillary vascular proliferation were significantly increased on days 7 and 14 in VEGF + FG group. Furthermore, there was a statistically significant difference in the mean bursting pressures between VEGF + FG group and other groups on days 7 and 14 (P < 0.05), and rabbits in VEGF + FG group exhibited a higher concentration than VEGF group (P < 0.05) and FG group (P < 0.05) on day 14. Conclusion: Administration of VEGF165 mixed with FG to ileal anastomosis accelerates wound healing and enhances the anastomosis by increased angiogenesis.

Engineering Bifunctional Antibodies with Constant Region Fusion Architectures

Du, Juanjuan,Cao, Yu,Liu, Yan,Wang, Ying,Zhang, Yong,Fu, Guangsen,Zhang, Yuhan,Lu, Lucy,Luo, Xiaozhou,Kim, Chan Hyuk,Schultz, Peter G.,Wang, Feng American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.51

<P>We report a method to generate bifunctional antibodies by grafting full-length proteins into constant region loops of a full-length antibody or an antigen-binding fragment (Fab). The fusion proteins retain the antigen binding activity of the parent antibody but have an additional activity associated with the protein insert. The engineered antibodies have excellent <I>in vitro</I> activity, physiochemical properties, and stability. Among these, a Her2 × CD3 bispecific antibody (BsAb) was constructed by inserting an anti-Her2 single-chain variable fragment (ScFv) into an anti-CD3 Fab. This bispecific antibody efficiently induces targeted cell lysis in the presence of effector cells at as low as sub-picomolar concentrations <I>in vitro</I>. Moreover, the Her2 × CD3 BsAb shows potent <I>in vivo</I> antitumor activity in mouse Her2<SUP>2+</SUP> and Her2<SUP>1+</SUP> xenograft models. These results demonstrate that insertion of a full-length protein into non-CDR loops of antibodies provides a feasible approach to generate multifunctional antibodies for therapeutic applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2017/jacsat.2017.139.issue-51/jacs.7b09641/production/images/medium/ja-2017-09641x_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja7b09641'>ACS Electronic Supporting Info</A></P>

Study on Electrical Aging Characteristics of Fiber Sheath Materials in Power Transformer Oil

Sun Lu,Fan Xiaozhou,Jiang Shuo,Wang Bowen,Liu Yunpeng,Gao Shuguo,Meng Lingming 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.1

Optical fiber has great potential in the development of online monitoring for trans-formers. In this paper, the electrical aging test of fiber sheath material based on a gradual voltage-rising method was performed and the influence of thermal aging on electrical aging was determined. Compared to the oil-paper insulation performance of traditional transformers, it was found that ethylene tetrafluoroethylene(ETFE), polytetrafluoroethylene(PTFE) and Polyamide 12 (PA 12) were better than oil-paper. Statistical analysis of the ETFE material and oil-paper test data was conducted using double-parameter Weibull distribution. The inverse power and exponential functions were used to fit the experimental data and voltage tolerance coefficients of the ETFE material were obtained. Experimental results show the parameters of the ETFE model in the inverse power function and exponential function model are better than those of the oil paper insulation, and the sheathed fiber is ETFE that can be stably operated in the transformer.

Stable colonization of Akkermansia muciniphila educates host intestinal microecology and immunity to battle against inflammatory intestinal diseases

Wang Bin,Chen Xuheng,Chen Zhiyuan,Xiao Huiwen,Dong Jiali,Li Yuan,Zeng Xiaozhou,Liu Jinjian,Wan Guoyun,Fan Saijun,Cui Ming 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Gut microbial preparations are widely used in treating intestinal diseases but show mixed success. In this study, we found that the therapeutic efficacy of A. muciniphila for dextran sodium sulfate (DSS)-induced colitis as well as intestinal radiation toxicity was ~50%, and mice experiencing a positive prognosis harbored a high frequency of A. muciniphila in the gastrointestinal (GI) tract. Stable GI colonization of A. muciniphila elicited more profound shifts in the gut microbial community structure of hosts. Coexisting with A. muciniphila facilitated proliferation and reprogrammed the gene expression profile of Lactobacillus murinus, a classic probiotic that overtly responded to A. muciniphila addition in a time-dependent manner. Then, a magnetic-drove, mannose-loaded nanophase material was designed and linked to the surface of A. muciniphila. The modified A. muciniphila exhibited enhancements in inflammation targeting and intestinal colonization under an external magnetic field, elevating the positive-response rate and therapeutic efficacy against intestinal diseases. However, the unlinked cocktail containing A. muciniphila and the delivery system only induced negligible improvement of therapeutic efficacy. Importantly, heat-inactivated A. muciniphila lost therapeutic effects on DSS-induced colitis and was even retained in the GI tract for a long time. Further investigations revealed that the modified A. muciniphila was able to drive M2 macrophage polarization by upregulating the protein level of IL-4 at inflammatory loci. Together, our findings demonstrate that stable colonization of live A. muciniphila at lesion sites is essential for its anti-inflammatory function.

Effect of Asymmetric Rolling on the Microstructure, Mechanical Properties and Texture Evolution of Mg–8Li–3Al–1Y Alloy

Xiao Zhou,Ruirui Liu,Qiang Liu,Haitao Zhou 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.5

Asymmetric rolling was applied to dual phase Mg–8Li–3Al–1Y alloy with different speed ratio and rolling reduction. Withincreasing reduction at the same speed ratio the population of β-Li grains decreased with a feature of fibered grains alongthe rolling direction. As for different speed ratio under the same reduction, β-Li grains kept equiaxed, but α-Mg phase wasfirst elongated and fibered and then transited to equiaxed small grains. The enhanced yield strength and tensile strengthwere achieved with the increase of rolling reduction and speed ratio. In particular, when speed ratio reached to 1:1.3 underthe same rolling reduction (30%), the optimal mechanical properties were obtained. As for texture evolution, we found thebasal texture was obviously weakened and some new weak texture was formed after asymmetric rolling. Interestingly, it wasnoted that the texture on the side of slow roll is distinct from that on the side of the fast roll due to the different rolling speed.

Characterization of Microstructure and Mechanical Properties of Mg–8Li–3Al–1Y Alloy Subjected to Different Rolling Processes

Xiao Zhou,Qiang Liu,Ruirui Liu,Haitao Zhou 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

The mechanical properties and microstructure evolution of Mg–8Li–3Al–1Y alloy undergoing different rolling processeswere systematically investigated. X-ray diffraction, optical microscope, scanning electron microscopy, transmission electronmicroscopy as well as electron backscattered diffraction were used for tracking the microstructure evolution. Tensile testingwas employed to characterize the mechanical properties. After hot rolling, the MgLi2Alprecipitated in β-Li matrix due to thetransformation reaction: β-Li → β-Li + MgLi2Al + α-Mg. As for the alloy subjected to annealed hot rolling, β-Li phase wasclearly recrystallized while recrystallization rarely occurred in α-Mg phase. With regard to the microstructure undergoing coldrolling, plenty of dislocations and dislocation walls were easily observed. In addition, the microstructure of alloys subjectedto annealed cold rolling revealed the formation of new fresh α-Mg grains in β-Li phase due to the precipitation reaction. Themechanical properties and fracture modes of Mg–8Li–3Al–1Y alloys can be effectively tuned by different rolling processes.