Summary： Alveolar epithelial type II （AT II） cells are essential for lung development and remodeling, as they are precursors for type I cells and also produce other non-repair cells （fibroblasts）. Progenitor ceil...Summary： Alveolar epithelial type II （AT II） cells are essential for lung development and remodeling, as they are precursors for type I cells and also produce other non-repair cells （fibroblasts）. Progenitor ceils are believed to possess capability of multi-potent transdifferentiation, which is closely related to the niche, suggesting the importance of establishment of a lung progenitor cell niche model. We hypothesized that pulmonary surfactant-associated protein A （SPA） suicide gene system would cause AT II cell to kill itself through apoptosis and leave its niche. In vitro, the recombinant adeno-associated virus vectors-SPA-thymidine kinase （rAAV-SPA-TK） system was established to get targeted apoptotic AT II cells. The apoptosis of AT II cells was detected by using MTT. The results showed that cloned SPA gene promoter had specific transcriptional activity in SPA high expression cells, and SPA high expression cells （H441） transfected with TK gene had higher sensitivity to ganciclovir （GCV） than SPA low expression cells （A549）. In vivo, increased apoptosis of AT II cells induced by GCV in rAAV-SPA-TK system was observed by TUNEL. Finally, the successful packaging and application of rAAV-SPA-TK system provide experimental basis to get specific lung progenitor cell （AT II） niche in vitro and in vivo.展开更多
The interfacial properties and rheological behavior of surfactant/polymer complex systems were measured to investigate the association behavior of the associating polymer.Compared with the pure surfactant solution,the...The interfacial properties and rheological behavior of surfactant/polymer complex systems were measured to investigate the association behavior of the associating polymer.Compared with the pure surfactant solution,there are two inflection points in the surface tension curve for the surfactant/polymer complex systems.The two inflection points are dependent on the surfactant type and polymer concentration.The effect of surfactant on the rheological behavior of polymer can be divided into two aspects.First,the addition of short-chain betaine surfactant is detrimental to the viscosity of polymer solution due to the electrostatic shielding effect.Second,long-chain betaine surfactant also reduces the viscosity of polymer solutions at low concentrations.However,when the concentration of the long-chain betaine surfactant is relatively high,the long-chain betaine surfactant could form worm-like micelles that promote the intermolecular association and thus increase the number of associating junctions,thereby resulting in the augmentation of viscosity.So it is necessary to apply the long-chain betaine surfactant to build the polymer/surfactant flooding system.The interaction model between surfactant and polymer is proposed,which is different from the traditional‘Three-Region Model’.展开更多
The rheological properties of three different microstructures of hydrophobically modified alkalisoluble polymers (telechelic, multisticker and combined) in the presence of various concentrations of anionic surfactant ...The rheological properties of three different microstructures of hydrophobically modified alkalisoluble polymers (telechelic, multisticker and combined) in the presence of various concentrations of anionic surfactant and salt (NaCl) were investigated. Associative polymers containing both ionic sites and small number of hydrophobic groups were obtained, and their thickening properties in aqueous solutions, were investigated. Solution polymerization was used for obtaining the different polymers. Relationships between hydrophobe, sodium dodecyl sulfate (SDS) and NaCl concentration are proposed. Owing to the competition between attractive hydrophobic interaction and repulsive electrostatic interactions, such hydrophobically modified polymers exhibit various rheological behaviors in aqueous solutions, depending on microstructure of polyelectrolyte, SDS and NaCl concentrations.展开更多
Objective To evaluate the alterations of biomarkers in the development and progression of coal workers＇ pneumoconiosis （CWP）. Methods The type and number of cells, and the levels of tumor necrosis factor-alpha （T...Objective To evaluate the alterations of biomarkers in the development and progression of coal workers＇ pneumoconiosis （CWP）. Methods The type and number of cells, and the levels of tumor necrosis factor-alpha （TNF-α）, pulmonary surfactant protein, phospholipids and fibronectin in bronchoalveolar lavage fluid were assayed in 14 health active coal miners, 21 coal miners without CWP and 13 miners with CWP of 0/1 to 1/1. Results Compared to active coal miners without CWP （8,23μg/mL）, TNF-α concentration was gradually decreased when dust exposure was stopped （5.90 μg/mL）. Elevated surfactant protein A （SP-A） level and phosphatidylglycerol （PG） to phosphatidylinositol （PI） ratio were found in miners actively exposed to coal dust （6528 μg/mL for SP-A and 10. for PG/P1）, and both parameters decreased when CWP progressed from CWP （0/1） （3419μg/mL for SP-A and 5.9 for PG/PI） to CWP （1/1） （1654 μg/mL for SP-A and 5.5 for PG/PI）. Conclusion Biomarkers in bronchoalveolar lavage fluid can be used to screen coal miners at high risk of developing coal workers＇ pneumoconiosis.展开更多
A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs a...A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units.展开更多
Background： Surfactant protein-A （SP-A） contributes to the regulation of sepsis-induced acute kidney injury. In a previous study, we demonstrated that the expression of SP-A in the human renal tubular epithelial （...Background： Surfactant protein-A （SP-A） contributes to the regulation of sepsis-induced acute kidney injury. In a previous study, we demonstrated that the expression of SP-A in the human renal tubular epithelial （HK-2） cells can be stimulated by lipopolysaccharide （LPS）. The present study evaluated the possible signal-transducing mechanisms of LPS-induced SP-A biosynthesis in the HK-2 cells. Methods： Tetrazolium salt colorimetry （MTT） assay was used to detect cell viability of HK-2 cells after LPS stimulation on different time points. HK-2 cells were stimulated with 100 ng/ml of LPS for different durations to determine the effects of LPS on SP-A and toll-like receptor 4 （TLR4） messenger RNA （mRNA） expression, as well as phosphorylation of mitogen-activated/ extracellular signal-regulated kinase （MEK） 1, extracellular signal-regulated kinase 1/2 （ERK1/2）, p38 mitogen-activated protein kinase （p38MAPK）, and nuclear factor-kappa B （NF-KB） inhibitor-alpha （IkB-a）. Then, HK-2 cells were pretreated with CLI-095, a TLR4 inhibitor, to analyze mRNA and protein levels of SP-A and TLR4 and expression of NF-KB ill the cytoplasm and nucleus of HK-2 before LPS exposure. Results： HK-2 cells exposed to 100 ng/ml of LPS for 1,6, and 24 h did not affect cell viability which showed no toxic effect of 100 ng/ml LPS on cells （P = 0.16）; however, the biosynthesis of SP-A mRNA and protein in HK-2 cells was significantly increased （P = 0.02）. As to the mechanism, LPS enhanced transmembrane receptor TLR4 protein expression. Sequentially, LPS time dependently augmented phosphorylation of MEKI, ERKI/2, and p38MAPK. In addition, levels of phospborylatedand nuclear NF-KB were augmented with LPS exposure for 2 h. LPS-induced SP-A and TLR4 mRNA as well as NF-KB expression were significantly inhibited by pretreatment with CLI-095. Conclusions： The present study exhibited that LPS can increase SP-A synthesis in human renal epithelial cells through sequentially activating the TLR4-related MEK1 -ERK 1/2-NF-kB-dependent pathway.展开更多
基金supported by the National Natural Science Foundation of China(No.30500224)
文摘Summary： Alveolar epithelial type II （AT II） cells are essential for lung development and remodeling, as they are precursors for type I cells and also produce other non-repair cells （fibroblasts）. Progenitor ceils are believed to possess capability of multi-potent transdifferentiation, which is closely related to the niche, suggesting the importance of establishment of a lung progenitor cell niche model. We hypothesized that pulmonary surfactant-associated protein A （SPA） suicide gene system would cause AT II cell to kill itself through apoptosis and leave its niche. In vitro, the recombinant adeno-associated virus vectors-SPA-thymidine kinase （rAAV-SPA-TK） system was established to get targeted apoptotic AT II cells. The apoptosis of AT II cells was detected by using MTT. The results showed that cloned SPA gene promoter had specific transcriptional activity in SPA high expression cells, and SPA high expression cells （H441） transfected with TK gene had higher sensitivity to ganciclovir （GCV） than SPA low expression cells （A549）. In vivo, increased apoptosis of AT II cells induced by GCV in rAAV-SPA-TK system was observed by TUNEL. Finally, the successful packaging and application of rAAV-SPA-TK system provide experimental basis to get specific lung progenitor cell （AT II） niche in vitro and in vivo.
基金Financial support by the Major Scientific and Technological Projects of CNPC under Grant(No.ZD 2019-183-007)。
文摘The interfacial properties and rheological behavior of surfactant/polymer complex systems were measured to investigate the association behavior of the associating polymer.Compared with the pure surfactant solution,there are two inflection points in the surface tension curve for the surfactant/polymer complex systems.The two inflection points are dependent on the surfactant type and polymer concentration.The effect of surfactant on the rheological behavior of polymer can be divided into two aspects.First,the addition of short-chain betaine surfactant is detrimental to the viscosity of polymer solution due to the electrostatic shielding effect.Second,long-chain betaine surfactant also reduces the viscosity of polymer solutions at low concentrations.However,when the concentration of the long-chain betaine surfactant is relatively high,the long-chain betaine surfactant could form worm-like micelles that promote the intermolecular association and thus increase the number of associating junctions,thereby resulting in the augmentation of viscosity.So it is necessary to apply the long-chain betaine surfactant to build the polymer/surfactant flooding system.The interaction model between surfactant and polymer is proposed,which is different from the traditional‘Three-Region Model’.
文摘The rheological properties of three different microstructures of hydrophobically modified alkalisoluble polymers (telechelic, multisticker and combined) in the presence of various concentrations of anionic surfactant and salt (NaCl) were investigated. Associative polymers containing both ionic sites and small number of hydrophobic groups were obtained, and their thickening properties in aqueous solutions, were investigated. Solution polymerization was used for obtaining the different polymers. Relationships between hydrophobe, sodium dodecyl sulfate (SDS) and NaCl concentration are proposed. Owing to the competition between attractive hydrophobic interaction and repulsive electrostatic interactions, such hydrophobically modified polymers exhibit various rheological behaviors in aqueous solutions, depending on microstructure of polyelectrolyte, SDS and NaCl concentrations.
基金This research was supported by University of Essen in Germany and Xishan Coal & Power Company
文摘Objective To evaluate the alterations of biomarkers in the development and progression of coal workers＇ pneumoconiosis （CWP）. Methods The type and number of cells, and the levels of tumor necrosis factor-alpha （TNF-α）, pulmonary surfactant protein, phospholipids and fibronectin in bronchoalveolar lavage fluid were assayed in 14 health active coal miners, 21 coal miners without CWP and 13 miners with CWP of 0/1 to 1/1. Results Compared to active coal miners without CWP （8,23μg/mL）, TNF-α concentration was gradually decreased when dust exposure was stopped （5.90 μg/mL）. Elevated surfactant protein A （SP-A） level and phosphatidylglycerol （PG） to phosphatidylinositol （PI） ratio were found in miners actively exposed to coal dust （6528 μg/mL for SP-A and 10. for PG/P1）, and both parameters decreased when CWP progressed from CWP （0/1） （3419μg/mL for SP-A and 5.9 for PG/PI） to CWP （1/1） （1654 μg/mL for SP-A and 5.5 for PG/PI）. Conclusion Biomarkers in bronchoalveolar lavage fluid can be used to screen coal miners at high risk of developing coal workers＇ pneumoconiosis.
文摘A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units.
文摘Background： Surfactant protein-A （SP-A） contributes to the regulation of sepsis-induced acute kidney injury. In a previous study, we demonstrated that the expression of SP-A in the human renal tubular epithelial （HK-2） cells can be stimulated by lipopolysaccharide （LPS）. The present study evaluated the possible signal-transducing mechanisms of LPS-induced SP-A biosynthesis in the HK-2 cells. Methods： Tetrazolium salt colorimetry （MTT） assay was used to detect cell viability of HK-2 cells after LPS stimulation on different time points. HK-2 cells were stimulated with 100 ng/ml of LPS for different durations to determine the effects of LPS on SP-A and toll-like receptor 4 （TLR4） messenger RNA （mRNA） expression, as well as phosphorylation of mitogen-activated/ extracellular signal-regulated kinase （MEK） 1, extracellular signal-regulated kinase 1/2 （ERK1/2）, p38 mitogen-activated protein kinase （p38MAPK）, and nuclear factor-kappa B （NF-KB） inhibitor-alpha （IkB-a）. Then, HK-2 cells were pretreated with CLI-095, a TLR4 inhibitor, to analyze mRNA and protein levels of SP-A and TLR4 and expression of NF-KB ill the cytoplasm and nucleus of HK-2 before LPS exposure. Results： HK-2 cells exposed to 100 ng/ml of LPS for 1,6, and 24 h did not affect cell viability which showed no toxic effect of 100 ng/ml LPS on cells （P = 0.16）; however, the biosynthesis of SP-A mRNA and protein in HK-2 cells was significantly increased （P = 0.02）. As to the mechanism, LPS enhanced transmembrane receptor TLR4 protein expression. Sequentially, LPS time dependently augmented phosphorylation of MEKI, ERKI/2, and p38MAPK. In addition, levels of phospborylatedand nuclear NF-KB were augmented with LPS exposure for 2 h. LPS-induced SP-A and TLR4 mRNA as well as NF-KB expression were significantly inhibited by pretreatment with CLI-095. Conclusions： The present study exhibited that LPS can increase SP-A synthesis in human renal epithelial cells through sequentially activating the TLR4-related MEK1 -ERK 1/2-NF-kB-dependent pathway.
