Dec2 inhibits macrophage pyroptosis to promote periodontal homeostasis

Dawei He,Xiaoyan Li,Fengzhu Zhang,Chen Wang,Yi Liu,Ujjal K. Bhawal,Jiang Sun 대한치주과학회 2022 Journal of Periodontal & Implant Science Vol.52 No.1

Purpose: Macrophages play crucial roles as early responders to bacterial pathogens and promote/ or impede chronic inflammation in various tissues. Periodontal macrophageinduced pyroptosis results in physiological and pathological inflammatory responses. The transcription factor Dec2 is involved in regulating immune function and inflammatory processes. To characterize the potential unknown role of Dec2 in the innate immune system, we sought to elucidate the mechanism that may alleviate macrophage pyroptosis in periodontal inflammation. Methods: Porphyromonas gingivalis lipopolysaccharide (LPS) was used to induce pyroptosis in RAW 264.7 macrophages. Subsequently, we established an LPS-stimulated Dec2 overexpression cellular model in macrophages. Human chronic periodontitis tissues were employed to evaluate potential changes in inflammatory marker expression and pyroptosis. Finally, the effects of Dec2 deficiency on inflammation and pyroptosis were characterized in a P. gingivalis-treated experimental periodontitis Dec2-knockout mouse model. Results: Macrophages treated with LPS revealed significantly increased messenger RNA expression levels of Dec2 and interleukin (IL)-1β. Dec2 overexpression reduced IL-1β expression in macrophages treated with LPS. Overexpression of Dec2 also repressed the cleavage of gasdermin D (GSDMD), and the expression of caspase-11 was concurrently reduced in macrophages treated with LPS. Human chronic periodontitis tissues showed significantly higher gingival inflammation and pyroptosis-related protein expression than non-periodontitis tissues. In vivo, P. gingivalis-challenged mice exhibited a significant augmentation of F4/80, tumor necrosis factor-α, and IL-1β. Dec2 deficiency markedly induced GSDMD expression in the periodontal ligament of P. gingivalis-challenged mice. Conclusions: Our findings indicate that Dec2 deficiency exacerbated P. gingivalis LPS-induced periodontal inflammation and GSDMD-mediated pyroptosis. Collectively, our results present novel insights into the molecular functions of macrophage pyroptosis and document an unforeseen role of Dec2 in pyroptosis.

Dec2 inhibits macrophage pyroptosis to promote periodontal homeostasis

He, Dawei,Li, Xiaoyan,Zhang, Fengzhu,Wang, Chen,Liu, Yi,Bhawal, Ujjal K.,Sun, Jiang Korean Academy of Periodontology 2021 Journal of Periodontal & Implant Science Vol.51 No.-

Purpose: Macrophages play crucial roles as early responders to bacterial pathogens and promote/ or impede chronic inflammation in various tissues. Periodontal macrophage-induced pyroptosis results in physiological and pathological inflammatory responses. The transcription factor Dec2 is involved in regulating immune function and inflammatory processes. To characterize the potential unknown role of Dec2 in the innate immune system, we sought to elucidate the mechanism that may alleviate macrophage pyroptosis in periodontal inflammation. Methods: Porphyromonas gingivalis lipopolysaccharide (LPS) was used to induce pyroptosis in RAW 264.7 macrophages. Subsequently, we established an LPS-stimulated Dec2 overexpression cellular model in macrophages. Human chronic periodontitis tissues were employed to evaluate potential changes in inflammatory marker expression and pyroptosis. Finally, the effects of Dec2 deficiency on inflammation and pyroptosis were characterized in a P. gingivalis-treated experimental periodontitis Dec2-knockout mouse model. Results: Macrophages treated with LPS revealed significantly increased messenger RNA expression levels of Dec2 and interleukin (IL)-1β. Dec2 overexpression reduced IL-1β expression in macrophages treated with LPS. Overexpression of Dec2 also repressed the cleavage of gasdermin D (GSDMD), and the expression of caspase-11 was concurrently reduced in macrophages treated with LPS. Human chronic periodontitis tissues showed significantly higher gingival inflammation and pyroptosis-related protein expression than non-periodontitis tissues. In vivo, P. gingivalis-challenged mice exhibited a significant augmentation of F4/80, tumor necrosis factor-α, and IL-1β. Dec2 deficiency markedly induced GSDMD expression in the periodontal ligament of P. gingivalis-challenged mice. Conclusions: Our findings indicate that Dec2 deficiency exacerbated P. gingivalis LPS-induced periodontal inflammation and GSDMD-mediated pyroptosis. Collectively, our results present novel insights into the molecular functions of macrophage pyroptosis and document an unforeseen role of Dec2 in pyroptosis.

A New FE Modeling Method for Isothermal Local Loading Process of Large-scale Complex Titanium Alloy Components Based on DEFORM-3D

Dawei Zhang,He Yang,Zhichao Sun,Xiaoguang Fan 한국소성가공학회 2010 기타자료 Vol.2010 No.6

Isothermal local loading process provides a new way to form large-scale complex titanium alloy components. The forming process is characterized by an extreme size (large scale in global and compared small size in regional), multi-parameter effects, and complicated loading path. To establish a reasonable finite element model is one of the key problems urgently to be solved in the research and development of isothermal local loading forming process of largescale complex titanium alloy components. In this paper, a new finite element model of the isothermal local loading process is developed under the DEFORM-3D environment based on the solution of some key techniques. The modeling method has the following features: (1) different meshing techniques are used in different loading areas and the number of meshed elements is determined according to the deformation characteristic in different local loading steps in order to improve computational efficiency; (2) the accurate magnitude of the friction factor under titanium alloy hot forming (isothermal forming) condition is adopted instead of the typical value for lubricated hot forming processes; (3) different FEM solvers are chosen at different stages according to the loading characteristic and the contact state; (4) in contrast to the local component model, a full 3D component is modeled to simulate the process. The 3D-FE model is validated by experimental data of a large-scale bulkhead forming under isothermal local loading. The model can describe the quantitative relationships between the forming conditions and the forming results. The results of the present study may provide a basis for studying the local deformation mechanism, selecting the reasonable parameters, optimizing the die design and the process control in isothermal local loading process of large-scale complex titanium alloy components.

The Research on the Effects of Electrical Aging on Trap Distribution in Polyethylene Doped with Nanoparticies

Lijuan He,Shan Wang,Chao Zhu,Haiping Xie,Dawei Li,Chuntian Chen 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.5

Effect of Anhydride Grafting Agent on Trap Levels of Low-Density Polyethylene

Lijuan He,Zhenhua Yuan,Xiong Yang,Huiqing Niu,Chao Zhu,Dawei Li,Lei Zhao,Chuntian Chen 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.5

Trap distribution of the low-density polyethylene(LDPE) modified by anhydride grafting agent was studied and the effect of grafting agent on the trap levels was analyzed by the method of Photo-stimulated Discharge in this paper. Different concentrations and types of same concentration of LDPE modified by anhydride grafting agent were measured by using continuous UV scanning. The results showed that different concentrations and types of grafting agent had effect on trap levels distribution of LDPE. The trap depth would decrease with the anhydride grafting agent content increasing and increase with its damaged condition increasing when anhydride grafting agent was destroyed. Anhydride grafting agent are widely applied to the production and research of high pressure insulating polyethylene materials. The purpose of this paper is to elaborate the effect of anhydride grafting agent on the insulating properties of polyethylene material and explain the strongest binding capacity of anhydride grafting agent to space charge.

Stiffness matching method for the ball screw feed drive system of machine tools

Gaiyun He,Panpan Shi,Dawei Zhang,Guangming Sun 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.7

The static stiffness of machine tools plays an important role in ensuring the performance of machine tools and improving the machining accuracy. In the design stage, stiffness matching provides a theoretical basis for determining the stiffness of each component. This study proposed a stiffness matching design method for machine tools. First, the deformation model of machine tools is established on the basis of the state space model. Through force analysis, the relationships between the deformations and stiffness of each part are determined. Second, the stiffness model of the machine tool is established by combining these relationships with the deformation model. Third, the objective function is determined by performing sensitivity analysis after obtaining the stiffness range. The stiffness matching design results are obtained through multi-objective linear programming. Lastly, the stiffness simulations, theoretical model, and experimental results are analyzed. The maximum errors among the experimental, simulation, and theoretical results (18.8 % and 19.9 %) are within the acceptable range. In conclusion, the proposed method is suitable for designing ball screw feed drive systems that requires rigidity.

Optimization Research of Effective Stimulation for Carbonate Reservoir and its Application

Anle He,Dawei Zhu,Chong Liang,Hewen Zhang,Jun Yan,Jianjun Xu 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.3

Based on the characteristics of carbonate reservoirs, staged-fracturing technology for horizontal wells was adopted to effectively drain the reservior. Fracture parameters including orientation, number, length, fracture conductivity and distribution were optimized, and accordingly a hydraulic fracturing design was developed. Applied in oilfield, this method was proved to be effective in oil production. Therefore, it can provide theoretical guidance for the design of the stage-fractured horizontal wells.

False-Negative Results of Real-Time ReverseTranscriptase Polymerase Chain Reaction for Severe Acute Respiratory Syndrome Coronavirus 2: Role of Deep-Learning-Based CT Diagnosis and Insights from Two Cases

Dasheng Li,Dawei Wang,Jianping Dong,Nana Wang,He Huang,Haiwang Xu,Chen Xia 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.4

The epidemic of 2019 novel coronavirus, later named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still gradually spreading worldwide. The nucleic acid test or genetic sequencing serves as the gold standard method for confirmation of infection, yet several recent studies have reported false-negative results of real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). Here, we report two representative false-negative cases and discuss the supplementary role of clinical data with rRT-PCR, including laboratory examination results and computed tomography features. Coinfection with SARS-COV-2 and other viruses has been discussed as well.

Model Predictive Torque Control of Surface Mounted Permanent Magnet Synchronous Motor Drives with Voltage Cost Functions

Zhang, Xiaoguang,Hou, Benshuai,He, Yikang,Gao, Dawei The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

In this paper, a model predictive torque control (MPTC) without the use of a weighting factor for surface mounted permanent-magnet synchronous machine (SPMSM) drive systems is presented. Firstly, the desired voltage vector is predicted in real time according to the principles of deadbeat torque and flux control. Then the sector of this desired voltage vector is determined. The complete enumeration for testing all of the feasible voltage vectors is avoided by testing only the candidate vectors contained in the sector. This means that only two voltage vectors in the sector need to be tested for selecting the optimal voltage vector in each control period. Thus, the calculation time can be reduced when compared with the conventional enumeration method. On the other hand, a novel cost function that only includes the dq-axis voltage errors between the desired voltage and candidate voltage is designed to eliminate the weighting factor used in the conventional MPTC. Thus, the control complexity caused by the tuning of the weighting factor is effectively decreased when compared with the conventional MPTC. Simulation and experimental investigation have been carried out to verify the proposed method.

Phase identification of $C_3N_4$ in CN films prepared by rf plasma chemical vapor deposition and dc magnetron sputtering

Fu, Dejun,Wu, Dawei,Zhang, Zhihong,Meng, Xianquan,He, Mengbing,Guo, Huaixi,Peng, Yougui,Fan, Xiangjun The Korean Vacuum Society 1998 Applied Science and Convergence Technology Vol.7 No.1

We prepared $C_3N_4$ films by rf plasma enhanced chemical vapor deposition(PCVD) and alternating $C_3N_4$/TiN composite films by dc magnetron sputtering. X-ray diffraction (XRD) and transmission electron diffraction (TED) revealed that the structure of the films is amorphous or polycrystalline, depending on deposition conditions and heat treatment. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy confirmed the presence of $sp_3\; and sp _2$ hybridized C atoms bonded with N atoms in the tetrahedral and hexagonal configurations, respectively. Graphite-free $C_3N_4$ films were obtained by PCVD under optimal conditions. To prepare well crystallized $C_3N_4$ films by magnetron sputtering, we introduced negatively biased gratings in the sputtering system. CN films deposited at grating voltages (Vg) lower than 400V are amorphous. Crystallites of cubic and $\beta$-$C_3N_4$ were formed at increased voltages.