Function of Rhs proteins in porcine extraintestinal pathogenic Escherichia coli PCN033

Lu Wenjia,Tan Jia,Lu Hao,Wang Gaoyan,Dong Wenqi,Wang Chenchen,Li Xiaodan,Tan Chen 한국미생물학회 2021 The journal of microbiology Vol.59 No.9

Extraintestinal pathogenic Escherichia coli (ExPEC) is an important zoonotic pathogen that places severe burdens on public health and animal husbandry. There are many pathogenic factors in E. coli. The type VI secretion system (T6SS) is a nano-microbial weapon that can assemble quickly and inject toxic effectors into recipient cells when danger is encountered. T6SSs are encoded in the genomes of approximately 25% of sequenced Gram-negative bacteria. When these bacteria come into contact with eukaryotic cells or prokaryotic microbes, the T6SS assembles and secretes associated effectors. In the porcine ExPEC strain PCN033, we identified four classic rearrangement hotspot (Rhs) genes. We determined the functions of the four Rhs proteins through mutant construction and protein expression. Animal infection experiments showed that the Δrhs-1CT, Δrhs-2CT, Δrhs-3CT, and Δrhs-4CT caused a significant decrease in the multiplication ability of PCN033 in vivo. Cell infection experiments showed that the Rhs protein is involved in anti-phagocytosis activities and bacterial adhesion and invasion abilities. The results of this study demonstrated that rhs1, rhs3, and rh4 plays an important role in the interaction between PCN033 and host cell. Rhs2 has contribution to cell and mice infection. This study helps to elucidate the pathogenic mechanism governing PCN033 and may help to establish a foundation for further research seeking to identify potential T6SS effectors.

Curcumin attenuates renal ischemia reperfusion injury via JNK pathway with the involvement of p300/CBP-mediated histone acetylation

Lu Yang,Xiaoxiang Chen,Zirong Bi,Jun Liao,Weian Zhao,Wenqi Huang 대한생리학회-대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.5

Apoptosis is proved responsible for renal damage during ischemia/reperfusion. The regulation for renal apoptosis induced by ischemia/reperfusion injury (IRI) has still been unclearly characterized to date. In the present study, we investigated the regulation of histone acetylation on IRI-induced renal apoptosis and the molecular mechanisms in rats with the application of curcumin possessing a variety of biological activities involving inhibition of apoptosis. Sprague–Dawley rats were randomized into four experimental groups (SHAM, IRI, curcumin, SP600125). Results showed that curcumin significantly decreased renal apoptosis and caspase-3/-9 expression and enhanced renal function in IRI rats. Treatment with curcumin in IRI rats also led to the decrease in expression of p300/cyclic AMP response element-binding protein (CBP) and activity of histone acetyltransferases (HATs). Reduced histone H3 lysine 9 (H3K9) acetylation was found near the promoter region of caspase-3/-9 after curcumin treatment. In a similar way, SP600125, an inhibitor of c-Jun N-terminal kinase (JNK), also attenuated renal apoptosis and enhanced renal function in IRI rats. In addition, SP600125 suppressed the binding level of p300/CBP and H3K9 acetylation near the promoter region of caspase-3/-9, and curcumin could inhibit JNK phosphorylation like SP600125. These results indicate that curcumin could attenuate renal IRI via JNK/p300/CBP-mediated anti-apoptosis signaling.

Effects of exposure to trace pyriproxyfen on the intestinal bacterial diversity and immune signal pathways of silkworm (Bombyx mori) larvae

Lu Qingyu,Li Guoli,Lan Huangli,Yu Dongliang,Yin Xingcan,Yang Wenqi,Yang Zehao,He Chunhui,Mo Danmei,Xu Kaizun 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.2

Silkworm (Bombyx mori) is a widely used lepidopteran model insect. Pyriproxyfen is an insect growth regulator (IGR) that can be used to control pests such as lepidoptera and diptera, and there is no research about its in fluence on the intestinal bacterial diversity and immune signal pathway of non-target lepidopteran insect larvae. In this study, we treated fifth-instar silkworms with trace pyriproxyfen (10 − 4 mg/L). The results showed that the abundance and diversity of silkworm larvae intestinal flora at the level of phylum, class, order, family and genus were all changed. The function prediction result showed that the functional changes mainly focused on tran scription, amino acid transport and metabolism, carbohydrate transport and metabolism, signal transduction mechanisms, energy production and conversion et al. after exposure to trace pyriproxyfen. Furthermore, qRTPCR results showed that trace pyriproxyfen exposure activated the transcriptions of antimicrobial peptides (AMPs) genes regulated by Toll and IMD pathways. This research can lay the foundation for the study on the resistance of lepidopteran insects to pyriproxyfen and other juvenile hormone pesticides.

Experimental Study on Deformation Behavior of Shield Tunnel Subjected to Riverbed Scour Based on DOFS

Xuanyi Lu,Kun Feng,Meilin Qi,Wenqi Guo 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.4

Exploring the deformation behavior of shield tunnels is significant to design and safety assessment for shield tunnel structures. This paper carries out a reduced scale model test of shield tunnel subjected to riverbed scour for the first time. A new loading device system is designed to simulate the initial stress field of stratum and effect of riverbed scour. Distributed optical fiber sensing (DOFS) technology is adopted as measuring method to achieve the surrounding soil deformation and structural deformation, ovality, and radius of curvature of shield tunnel. The test results show that uneven rebound deformation of stratum and shield tunnel structure occurs in both transverse and longitudinal directions under the action of riverbed scour. Variations in ovality differences exist along the longitudinal direction of the shield tunnel, indicating that the transverse and longitudinal deformation of the shield tunnel affects each other. The radius of curvature of the longitudinal deformation of the shield tunnel at the vault is much smaller than that of the bottom. The results demonstrate the broad application value of DOFS technology in shield tunnel structure monitoring and reveal the deformation mechanism of shield tunnels subjected to riverbed scour, which can provide important reference values for the structure design and safety monitoring of shield tunnels.

Benchtop fabrication of three-dimensional reconfigurable microfluidic devices from paper-polymer composite.

Han, Yu Long,Wang, Wenqi,Hu, Jie,Huang, Guoyou,Wang, Shuqi,Lee, Won Gu,Lu, Tian Jian,Xu, Feng Royal Society of Chemistry 2013 Lab on a chip Vol.13 No.24

<P>We presented a benchtop technique that can fabricate reconfigurable, three-dimensional (3D) microfluidic devices made from a soft paper-polymer composite. This fabrication approach can produce microchannels at a minimal width of 100 μm and can be used to prototype 3D microfluidic devices by simple bending and stretching. The entire fabrication process can be finished in 2 hours on a laboratory bench without the need for special equipment involved in lithography. Various functional microfluidic devices (e.g., droplet generator and reconfigurable electronic circuit) were prepared using this paper-polymer hybrid microfluidic system. The developed method can be applied in a wide range of standard applications and emerging technologies such as liquid-phase electronics.</P>

Major ginsenosides from Panax ginseng promote aerobic cellular respiration and SIRT1-mediated mitochondrial biosynthesis in cardiomyocytes and neurons

Huang, Qingxia,Lou, Tingting,Lu, Jing,Wang, Manying,Chen, Xuenan,Xue, Linyuan,Tang, Xiaolei,Qi, Wenxiu,Zhang, Zepeng,Su, Hang,Jin, Wenqi,Jing, Chenxu,Zhao, Daqing,Sun, Liwei,Li, Xiangyan The Korean Society of Ginseng 2022 Journal of Ginseng Research Vol.46 No.6

Background: Aerobic cellular respiration provides chemical energy, adenosine triphosphate (ATP), to maintain multiple cellular functions. Sirtuin 1 (SIRT1) can deacetylate peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) to promote mitochondrial biosynthesis. Targeting energy metabolism is a potential strategy for the prevention and treatment of various diseases, such as cardiac and neurological disorders. Ginsenosides, one of the major bioactive constituents of Panax ginseng, have been extensively used due to their diverse beneficial effects on healthy subjects and patients with different diseases. However, the underlying molecular mechanisms of total ginsenosides (GS) on energy metabolism remain unclear. Methods: In this study, oxygen consumption rate, ATP production, mitochondrial biosynthesis, glucose metabolism, and SIRT1-PGC-1α pathways in untreated and GS-treated different cells, fly, and mouse models were investigated. Results: GS pretreatment enhanced mitochondrial respiration capacity and ATP production in aerobic respiration-dominated cardiomyocytes and neurons, and promoted tricarboxylic acid metabolism in cardiomyocytes. Moreover, GS clearly enhanced NAD⁺-dependent SIRT1 activation to increase mitochondrial biosynthesis in cardiomyocytes and neurons, which was completely abrogated by nicotinamide. Importantly, ginsenoside monomers, such as Rg1, Re, Rf, Rb1, Rc, Rh1, Rb2, and Rb3, were found to activate SIRT1 and promote energy metabolism. Conclusion: This study may provide new insights into the extensive application of ginseng for cardiac and neurological protection in healthy subjects and patients.

A Dynamic Control Method for Cavs Platoon Based on the MPC Framework and Safety Potential Field Model

Linheng Li,Jing Gan,Xu Qu,Wenqi Lu,Peipei Mao,Bin Ran 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.5

Safety and efficiency have always been significant challenges to the development of road traffic. Detailed vehicle motion information is the prerequisite for achieving optimal control of the platoon and improving traffic safety and efficiency. The connected and automated vehicles (CAVs) system has offered unprecedented opportunities for the real-time collection and processing of these detailed vehicle motion data. Based on the model predictive control (MPC) framework and safety potential field (SPF) model, we developed an alternative CAVs platoon dynamic control method. The SPF model was applied to describe the road risk distribution under the complex driving environment and was embedded in the MPC framework to optimize the vehicle dynamics from the perspective of capacity, safety, and energy-saving. Also, some experiments were performed to verify the validity of our platoon control strategy. Compared with the fixed time-headway strategy, our proposed strategy can increase the traffic capacity by about 24.4%, while ensuring safety and improving fuel economy. The results indicate that the novel CAVs platoon control methodology proposed in this paper can be potentially applied to alleviate various traffic problems (e.g., traffic congestion, traffic accidents, and high emissions).

Synthesis and Enhanced Photocatalytic Activity of Black Porous Zr-doped TiO2 Monoliths

Jimin Du,Huiming Wang,Huijuan Chen,Menghe Yang,Xiaoling Lu,Hui Guo,Zhanmin Zhang,Tianwei Shang,Shujue Xu,Wenqi Li,Pianpian Wang,Imran Shakir 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.6

Black Porous Zr-doped TiO2 monoliths were successfully synthesized by a combined route including sol–gel method with polystyrene spheres as template followed by calcination at high temperature in the presence of oxygen. As-synthesized samples were then treated in hydrogen atmosphere at 500℃ for 6 h to obtain black Porous Zr-doped TiO2 monoliths. This as-synthesized black porous Zr-doped TiO2 composite showed relatively narrow bandgap compared to the pure anatase phase of TiO2, which may have its origin from the contributions from the Zr impurity and oxygen vacancies. The photocatalytic activity of the black porous Zr-doped TiO2 monolith was examined by carrying out the dye degradation on Rhodamine B under visible irradiation. Our experimental results indicate that black porous 0.9% Zr-doped TiO2 sample exhibits high photocatalytic activity with the photodecomposition of 95.25% under visible irradiation for 120 min.