AIM To investigate the role of peritoneal macrophage(PM) polarization in the therapeutic effect of abdominal paracentesis drainage(APD) on severe acute pancreatitis(SAP).METHODS SAP was induced by 5% Na-taurocholate r...AIM To investigate the role of peritoneal macrophage(PM) polarization in the therapeutic effect of abdominal paracentesis drainage(APD) on severe acute pancreatitis(SAP).METHODS SAP was induced by 5% Na-taurocholate retrograde injection in Sprague-Dawley rats. APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after the induction of SAP. To verify the effect of APD on macrophages, PMs were isolated and cultured in an environment, with the peritoneal inflammatory environment simulated by the addition of peritoneal lavage in complete RPMI 1640 medium. Hematoxylin and eosin staining was performed. The levels of pancreatitis biomarkers amylase and lipase as well as the levels of inflammatory mediators in the blood and peritoneal lavage were determined. The polarization phenotypes of the PMs were identified by detecting the marker expression of M1/M2 macrophages via flow cytometry, qPCR and immunohistochemical staining. The protein expression in macrophages that had infiltrated the pancreas was determined by Western blot.RESULTS APD treatment significantly reduced the histopathological scores and levels of amylase, lipase, tumor necrosis factor-α and interleukin(IL)-1β, indicating that APD ameliorates the severity of SAP. Importantly, we found that APD treatment polarized PMs towards the M2 phenotype, as evidenced by the reduced number of M1 macrophages and the reduced levels of proinflammatory mediators, such as IL-1β and L-selectin, as well as the increased number of M2 macrophages and increased levels of anti-inflammatory mediators, such as IL-4 and IL-10. Furthermore, in an in vitro study wherein peritoneal lavage from the APD group was added to the cultured PMs to simulate the peritoneal inflammatory environment, PMs also exhibited a dominant M2 phenotype, resulting in a significantly lower level of inflammation. Finally, APD treatment increased the proportion of M2 macrophages and upregulated the expression of the anti-inflammatory protein Arg-1 in the pancreas of SAP model rats.CONCLUSION These findings suggest that APD treatment exerts antiinflammatory effects by regulating the M2 polarization of PMs, providing novel insights into the mechanism underlying its therapeutic effect.展开更多
The quality of the scanning tip is crucial for tip-enhanced Raman spectroscopy(TERS)experiments towards large signal enhancement and high spatial resolution.In this work,we report a controllable fabrication method to ...The quality of the scanning tip is crucial for tip-enhanced Raman spectroscopy(TERS)experiments towards large signal enhancement and high spatial resolution.In this work,we report a controllable fabrication method to prepare TERS-active tips by modifying the tip apex at the atomic scale,and propose two important criteria to in-situ judge the tip’s TERS activity for tip-enhanced Raman measurements.One criterion is based on the downshift of the first image potential state to monitor the coupling between the far-field incident laser and near-field plasmon;the other is based on the appearance of the low-wavenumber Raman peaks associated with an atomistic protrusion at the tip apex to judge the coupling efficiency of emissions from the near field to the far field.This work provides an effective method to quickly fabricate and judge TERS-active tips before real TERS experiments on target molecules and other materials,which is believed to be instrumental for the development of TERS and other tip-enhanced spectroscopic techniques.展开更多
Single-molecule tip-enhanced Raman spectroscopy(TERS)has emerged as an important technique for structural analysis at sub-molecular scale.Here in this work,we report a TERS study of an isolated free-base porphyrin mol...Single-molecule tip-enhanced Raman spectroscopy(TERS)has emerged as an important technique for structural analysis at sub-molecular scale.Here in this work,we report a TERS study of an isolated free-base porphyrin molecule adsorbed on the Ag(100)surface at cryogenic temperature(~7 K).Site-dependent TERS spectra reveal distinct local vibrational information for the chemical constituents within a single molecule.Moreover,distinct spatial features among different Raman peaks can be resolved from the TERS mapping images.These images are found to associate with related vibrational modes,enabling to resolve the mode associated with N-H bonds at the sub-nanometer level.This study will provide deep insights into the symmetry of adsorption configurations and local vibrational information within a single molecule.展开更多
基金the National Natural Science Foundation of China,No.81772001,No.8177071311 and No.81502696the National Clinical Key Subject of China,No.41792113+1 种基金the Technology Plan Program of Sichuan Province,No.2015SZ0229,No.2018JY0041 and No.18YYJC0442the Science and Technology Development Plan of Sichuan Province,No.2016YJ0023
文摘AIM To investigate the role of peritoneal macrophage(PM) polarization in the therapeutic effect of abdominal paracentesis drainage(APD) on severe acute pancreatitis(SAP).METHODS SAP was induced by 5% Na-taurocholate retrograde injection in Sprague-Dawley rats. APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after the induction of SAP. To verify the effect of APD on macrophages, PMs were isolated and cultured in an environment, with the peritoneal inflammatory environment simulated by the addition of peritoneal lavage in complete RPMI 1640 medium. Hematoxylin and eosin staining was performed. The levels of pancreatitis biomarkers amylase and lipase as well as the levels of inflammatory mediators in the blood and peritoneal lavage were determined. The polarization phenotypes of the PMs were identified by detecting the marker expression of M1/M2 macrophages via flow cytometry, qPCR and immunohistochemical staining. The protein expression in macrophages that had infiltrated the pancreas was determined by Western blot.RESULTS APD treatment significantly reduced the histopathological scores and levels of amylase, lipase, tumor necrosis factor-α and interleukin(IL)-1β, indicating that APD ameliorates the severity of SAP. Importantly, we found that APD treatment polarized PMs towards the M2 phenotype, as evidenced by the reduced number of M1 macrophages and the reduced levels of proinflammatory mediators, such as IL-1β and L-selectin, as well as the increased number of M2 macrophages and increased levels of anti-inflammatory mediators, such as IL-4 and IL-10. Furthermore, in an in vitro study wherein peritoneal lavage from the APD group was added to the cultured PMs to simulate the peritoneal inflammatory environment, PMs also exhibited a dominant M2 phenotype, resulting in a significantly lower level of inflammation. Finally, APD treatment increased the proportion of M2 macrophages and upregulated the expression of the anti-inflammatory protein Arg-1 in the pancreas of SAP model rats.CONCLUSION These findings suggest that APD treatment exerts antiinflammatory effects by regulating the M2 polarization of PMs, providing novel insights into the mechanism underlying its therapeutic effect.
基金supported by the National Key R&D Program of China(No.2016YFA0200600)the National Natural Science Foundation of China(No.21790352,No.22174135)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000)Anhui Initiative in Quantum Information Technologies(No.AHY090100)。
文摘The quality of the scanning tip is crucial for tip-enhanced Raman spectroscopy(TERS)experiments towards large signal enhancement and high spatial resolution.In this work,we report a controllable fabrication method to prepare TERS-active tips by modifying the tip apex at the atomic scale,and propose two important criteria to in-situ judge the tip’s TERS activity for tip-enhanced Raman measurements.One criterion is based on the downshift of the first image potential state to monitor the coupling between the far-field incident laser and near-field plasmon;the other is based on the appearance of the low-wavenumber Raman peaks associated with an atomistic protrusion at the tip apex to judge the coupling efficiency of emissions from the near field to the far field.This work provides an effective method to quickly fabricate and judge TERS-active tips before real TERS experiments on target molecules and other materials,which is believed to be instrumental for the development of TERS and other tip-enhanced spectroscopic techniques.
基金supported by the National Key R&D Program of China(No.2016YFA0200600)the National Natural Science Foundation of China,the Chinese Academy of Sciences+1 种基金Anhui Initiative in Quantum Information TechnologiesAtif Ghafoor acknowledges support by the China Scholarship Council
文摘Single-molecule tip-enhanced Raman spectroscopy(TERS)has emerged as an important technique for structural analysis at sub-molecular scale.Here in this work,we report a TERS study of an isolated free-base porphyrin molecule adsorbed on the Ag(100)surface at cryogenic temperature(~7 K).Site-dependent TERS spectra reveal distinct local vibrational information for the chemical constituents within a single molecule.Moreover,distinct spatial features among different Raman peaks can be resolved from the TERS mapping images.These images are found to associate with related vibrational modes,enabling to resolve the mode associated with N-H bonds at the sub-nanometer level.This study will provide deep insights into the symmetry of adsorption configurations and local vibrational information within a single molecule.
