背景:菌斑生物膜引发的宿主免疫反应是牙周炎进展和破坏的始作俑者,巨噬细胞是参与其中的主要免疫细胞,在炎症发生发展过程中发挥着重要作用。目的:主要对巨噬细胞极化与牙周炎的关系及通过调控巨噬细胞极化治疗牙周炎的相关进展进行综...背景:菌斑生物膜引发的宿主免疫反应是牙周炎进展和破坏的始作俑者,巨噬细胞是参与其中的主要免疫细胞,在炎症发生发展过程中发挥着重要作用。目的:主要对巨噬细胞极化与牙周炎的关系及通过调控巨噬细胞极化治疗牙周炎的相关进展进行综述。方法:应用计算机检索PubMed和中国知网数据库1990-2023年发表的相关文献,英文检索词为“macrophage polarization,M1/M2 macrophage,periodontitis,periodontitis treatment,macrophage polarization and periodontitis,osteoimmunology,ferroptosis,macrophage polarization and ferroptosis,periodontitis and ferroptosis”,中文检索词为“巨噬细胞极化,M1/M2巨噬细胞,牙周炎,牙周炎治疗,骨免疫,铁死亡”。经初筛后,选定96篇文献进行综述。结果与结论:巨噬细胞不同表型之间的转换与牙周炎组织破坏密切相关,其分泌的多种细胞因子和炎症递质参与调控了牙周组织的破坏与修复过程,调节巨噬细胞表型及细胞因子分泌有助于降低牙周炎炎症水平、改善牙周微环境,从而减少组织破坏或促进牙周组织再生。目前已有许多研究着力于开发药物或生物材料来调节巨噬细胞功能,从而达到免疫调控治疗牙周炎的目的,但由于巨噬细胞的作用贯穿牙周炎发生发展过程,在抗感染、骨破坏和骨修复过程中均扮演重要角色,且极化本身是一个复杂的动态过程,受诸多因素的影响,所以仍需探索更多可能的机制来明确材料或药物与巨噬细胞间的交互作用。展开更多
The electrochemical corrosion behaviors of the welded joints of 2205 duplex stainless steel with the laser continuous heat treatment were investigated. The secondary austenite formation is the outcome of thermodynamic...The electrochemical corrosion behaviors of the welded joints of 2205 duplex stainless steel with the laser continuous heat treatment were investigated. The secondary austenite formation is the outcome of thermodynamic equilibrium breach of the alloy during heat treatment and the result of the continuous heat treatment which has the most important effect on the weld material. The partitioning behaviors of chromium and molybdenum as well as the volume fraction of ferrite and austenite have a remarkable influence on the composition of the individual phase. Mechanical examination of the laser trated weld demonstrates that the tensile strength and yield strength increase with increasing the amount of the secondary austenite. It is shown that the ultimate tensile strength of the 6 kW laser-treated weld is higher about 20 MPa than no heat treatment weld and the ductility can be further improved without compromising strength. The results indicate that the welding alters the corrosion behavior because of different post heat treatment power and the broad active peak is not identified which is attributed to the dissolution of the secondary austenitic in the ferrite phase. It is indicated that pitting resistance equivalent （PRE） values of base metal and 6 kW weld are higher than that of other welds; base metal is 33.7, 6 kW weld 33.3, no treatment 32.4, 4 kW weld 32.8, 8 kW weld 32.5. The extent of corrosion resistance improvement after reheating treatment is mainly caused by the removal of nitrogen from ferritic regions, which occurred as a consequence of secondary austenite growth.展开更多
In the present research, the influence of chromium enrichment by surface treatment on corrosion resistance of type 316L stainless steel in body environment was investigated. For this study, weight loss test during 18 ...In the present research, the influence of chromium enrichment by surface treatment on corrosion resistance of type 316L stainless steel in body environment was investigated. For this study, weight loss test during 18 months, cyclic and liner polarization tests before and after surface treatment and metallography by electron and light microscopy were used to evaluate the effectiveness of the proposed method. In addition, X-ray photoelectron spectroscopy （XPS） method was used to determine the chromium concentration in the surface layer after surface treatment. Results show that the surface treatment has improved corrosion resistance of the type 316L stainless steel in body environment.展开更多
The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurem...The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurements. The results of immersion test show that NK30 alloy exhibits better corrosion resistance in F condition than it does in the other two conditions due to the more compact corrosion film formed on alloy in F condition. The potentiodynamic polarization curves show that the overpotential of cathodic hydrogen evolution reaction on NK30-F is much higher than that on NK30-T4 and NK30-T6. The corrosion potentials of NK30 increase in the following order: F<T4<T6. The results of electrochemical impedance spectroscopy (EIS) also confirm that the corrosion film of NK30-F plays a more protective role than that of NK30-T4 and NK30-T6.展开更多
文摘背景:菌斑生物膜引发的宿主免疫反应是牙周炎进展和破坏的始作俑者,巨噬细胞是参与其中的主要免疫细胞,在炎症发生发展过程中发挥着重要作用。目的:主要对巨噬细胞极化与牙周炎的关系及通过调控巨噬细胞极化治疗牙周炎的相关进展进行综述。方法:应用计算机检索PubMed和中国知网数据库1990-2023年发表的相关文献,英文检索词为“macrophage polarization,M1/M2 macrophage,periodontitis,periodontitis treatment,macrophage polarization and periodontitis,osteoimmunology,ferroptosis,macrophage polarization and ferroptosis,periodontitis and ferroptosis”,中文检索词为“巨噬细胞极化,M1/M2巨噬细胞,牙周炎,牙周炎治疗,骨免疫,铁死亡”。经初筛后,选定96篇文献进行综述。结果与结论:巨噬细胞不同表型之间的转换与牙周炎组织破坏密切相关,其分泌的多种细胞因子和炎症递质参与调控了牙周组织的破坏与修复过程,调节巨噬细胞表型及细胞因子分泌有助于降低牙周炎炎症水平、改善牙周微环境,从而减少组织破坏或促进牙周组织再生。目前已有许多研究着力于开发药物或生物材料来调节巨噬细胞功能,从而达到免疫调控治疗牙周炎的目的,但由于巨噬细胞的作用贯穿牙周炎发生发展过程,在抗感染、骨破坏和骨修复过程中均扮演重要角色,且极化本身是一个复杂的动态过程,受诸多因素的影响,所以仍需探索更多可能的机制来明确材料或药物与巨噬细胞间的交互作用。
基金Funded by the Major State Basic Research Development Program of China (973 Program) (No.2011CB706604)the R&D Project from Department of Railway(No. 2010G023)
文摘The electrochemical corrosion behaviors of the welded joints of 2205 duplex stainless steel with the laser continuous heat treatment were investigated. The secondary austenite formation is the outcome of thermodynamic equilibrium breach of the alloy during heat treatment and the result of the continuous heat treatment which has the most important effect on the weld material. The partitioning behaviors of chromium and molybdenum as well as the volume fraction of ferrite and austenite have a remarkable influence on the composition of the individual phase. Mechanical examination of the laser trated weld demonstrates that the tensile strength and yield strength increase with increasing the amount of the secondary austenite. It is shown that the ultimate tensile strength of the 6 kW laser-treated weld is higher about 20 MPa than no heat treatment weld and the ductility can be further improved without compromising strength. The results indicate that the welding alters the corrosion behavior because of different post heat treatment power and the broad active peak is not identified which is attributed to the dissolution of the secondary austenitic in the ferrite phase. It is indicated that pitting resistance equivalent （PRE） values of base metal and 6 kW weld are higher than that of other welds; base metal is 33.7, 6 kW weld 33.3, no treatment 32.4, 4 kW weld 32.8, 8 kW weld 32.5. The extent of corrosion resistance improvement after reheating treatment is mainly caused by the removal of nitrogen from ferritic regions, which occurred as a consequence of secondary austenite growth.
文摘In the present research, the influence of chromium enrichment by surface treatment on corrosion resistance of type 316L stainless steel in body environment was investigated. For this study, weight loss test during 18 months, cyclic and liner polarization tests before and after surface treatment and metallography by electron and light microscopy were used to evaluate the effectiveness of the proposed method. In addition, X-ray photoelectron spectroscopy （XPS） method was used to determine the chromium concentration in the surface layer after surface treatment. Results show that the surface treatment has improved corrosion resistance of the type 316L stainless steel in body environment.
基金Project(5133003C) supported by the Major State Basic Research Development Program of China
文摘The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurements. The results of immersion test show that NK30 alloy exhibits better corrosion resistance in F condition than it does in the other two conditions due to the more compact corrosion film formed on alloy in F condition. The potentiodynamic polarization curves show that the overpotential of cathodic hydrogen evolution reaction on NK30-F is much higher than that on NK30-T4 and NK30-T6. The corrosion potentials of NK30 increase in the following order: F<T4<T6. The results of electrochemical impedance spectroscopy (EIS) also confirm that the corrosion film of NK30-F plays a more protective role than that of NK30-T4 and NK30-T6.
