The soil-rock mixture,a collection of soil particles and rock blocks,is inherently heterogeneous and anisotropic due to significant particle size and material strength differences.This study conducts triaxial tests on...The soil-rock mixture,a collection of soil particles and rock blocks,is inherently heterogeneous and anisotropic due to significant particle size and material strength differences.This study conducts triaxial tests on soil-rock mixture samples of various compactness subjected to varying freeze-thaw cycles.A mesoscopic simulation is carried out by particle flow code(PFC)to analyze the effects of freeze-thaw cycles on the mechanical properties of soil and rock particles.The results show that the mechanical properties of the soil-rock mixture under freeze-thaw cycles are greatly affected by the initial compaction.In general,when the degree of compaction is higher,the influence of freeze-thaw cycles on the soil-rock mixture is greater.The stress-strain curves of the samples with different compactness demonstrate strain-softening behavior.The freeze-thaw cycles greatly influence the failure strength of the samples with a higher degree of compaction but have little impact on the samples with a lower degree of compaction.On the microscopic level,during freeze-thaw cycles,the pore volume in the highly compacted sample is too small to accommodate the volume expansion from ice crystal formation,causing significant strength loss among the soil and rock particles and deterioration of the macroscopic properties of the soil-rock mixture.展开更多
Objective The aim of this study was to analyze and evaluate 1.32-μm and 1.06-μm neodymium-doped yttrium aluminum garnet(Nd:YAG) lasers for use in liver and gastroepiploic vessel vaporization and coagulation. Methods...Objective The aim of this study was to analyze and evaluate 1.32-μm and 1.06-μm neodymium-doped yttrium aluminum garnet(Nd:YAG) lasers for use in liver and gastroepiploic vessel vaporization and coagulation. Methods The effects of 1.32-μm and 1.06-μm Nd:YAG lasers were compared for gastroepiploic vessel hemostasis in porcine liver.Results The results were observed and measured under the same parameters and dose conditions. The 1.32-μm laser showed greater vaporization width and depth than the 1.06-μm laser. Both lasers controlled active bleeding. The coagulation band with the 1.32-μm laser was thinner than with the 1.06-μm laser, at nearly 3 mm. After cutting of 1-and 2-mm porcine vessels, no grossly visible bleeding was apparent. Intravascular thrombus was visible under the microscope. The length of vessel thrombosis in the experimental group was 2 mm and the diameter was 2 mm; the control group exhibited thrombi as 2.3–4.9 mm in length. Thrombosis completely blocked the blood vessels.Conclusion The 1.32-μm laser had greater vaporization capability than the 1.06-μm laser and achieved hemostasis requirements for vessels less than 2 mm in diameter.展开更多
Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous systems.In the past few decades,breakthrough progress has been made in the gut liver bra...Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous systems.In the past few decades,breakthrough progress has been made in the gut liver brain axis,mainly through understanding its formation mechanism and increasing treatment strategies.In this review,we discuss various complex networks including barrier permeability,gut hormones,gut microbial metabolites,vagus nerve,neurotransmitters,immunity,brain toxic metabolites,β-amyloid(Aβ)metabolism,and epigenetic regulation in the gut-liver-brain axis.Some therapies containing antibiotics,probiotics,prebiotics,synbiotics,fecal microbiota transplantation(FMT),polyphenols,low FODMAP diet and nanotechnology application regulate the gut liver brain axis.Besides,some special treatments targeting gut-liver axis include farnesoid X receptor(FXR)agonists,takeda G protein-coupled receptor 5(TGR5)agonists,glucagon-like peptide-1(GLP-1)receptor antagonists and fibroblast growth factor 19(FGF19)analogs.Targeting gut-brain axis embraces cognitive behavioral therapy(CBT),antidepressants and tryptophan metabolism-related therapies.Targeting liver-brain axis contains epigenetic regulation and Aβmetabolism-related therapies.In the future,a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.展开更多
Objective:Pseudostellaria heterophylla has been paid more attention in recent years,mainly as a medicine food homology plant.The content determination of P.heterophylla is not specified in the Chinese Pharmacopoeia(ve...Objective:Pseudostellaria heterophylla has been paid more attention in recent years,mainly as a medicine food homology plant.The content determination of P.heterophylla is not specified in the Chinese Pharmacopoeia(version 2020).The environmental conditions in different production areas could exert an influence on the quality of P.heterophylla.The purpose of this study is to discriminate P.heterophylla collected from different geographical origins of China.Methods:In this study,the content of polysaccharide in 28 batches of P.heterophylla was determined using phenol–sulfuric acid.HPLC fingerprints were established under optimised HPLC-PDA methods.Subsequently,the similarity analysis(SA)and the quantification of heterophyllin B were analyzed.The metabolites of P.heterophylla were identified and evaluated using UHPLC-Q Exactive HF orbitrap MS system.Principal component analysis(PCA),partial least squares discriminant analysis(PLS-DA),hierarchical cluster analysis(HCA)and orthogonal PLS-DA(OPLS-DA)were performed based on all peak areas.Results:The polysaccharide content in Guizhou and Jiangsu was higher than that of other production areas,which varied significant from different origins.While the content of heterophyllin B in Anhui and Jiangsu was high.The correlation coefficients of HPLC fingerprints for 28 batches samples ranged from 0.877 to 0.990,and the characteristic map can be used to identify and evaluate the quality of P.heterophylla.The samples from Fujian,Guizhou,Jiangsu provinces can be relatively separated using multivariate statistical analysis including PCA,PLS-DA,HCA,OPLS-DA,indicating that their metabolic compositions were significantly different.Ultimately,a total of 15 metabolites which were filtrated by a VIPvalue>1 and a P-value<0.05 associated with the separation of different origins were identified.Conclusion:HPLC fingerprint was established to evaluate the quality and authenticity of P.heterophylla.The present work showed that the difference of geographic distributions had an influence on the internal chemical compositions.A sensitive and rapid untargeted metabolomics approach by UHPLC-Q Exactive HF orbitrap MS was utilized to evaluate P.heterophylla from different origins in China for the first time.Overall,this study provides insights to metabolomics of P.heterophylla and supplies important reference values for the development of functional foods.展开更多
The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improv...The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improve yields of Rgin a Panax ginseng chassis,combining engineering of triterpene metabolism and overexpression of a lignin biosynthesis gene,phenylalanine ammonia lyase(PAL).We first performed semi-rational design and site mutagenesis to improve the enzymatic efficiency of Pq3-O-UGT2,a glycosyltransferase that directly catalyzes the biosynthesis of Rgfrom Rh.Next,we used clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing to knock down the branch pathway of protopanaxatriol-type ginsenoside biosynthesis to enhance the metabolic flux of the protopanaxadiol-type ginsenoside Rg.Overexpression of PAL accelerated the formation of the xylem structure,significantly improving ginsenoside Rgaccumulation(to 6.19-fold higher than in thecontrol).Wecombinedoverexpression of the ginsenoside aglycon synthetic genes squalene epoxidase,Pq3-O-UGT2,and PAL with CRISPR/Cas9-based knockdown of CYP716A53v2 to improve ginsenoside Rgaccumulation.Finally,we produced ginsenoside Rgat a yield of 83.6 mg/L in a shake flask(7.0 mg/g dry weight,21.12-fold higher than with wild-type cultures).The highproduction system established in this study could be a potential platform to produce the ginsenoside Rgcommercially for pharmaceutical use.展开更多
A reliable and accurate liquid chromatography with evaporative light scattering detection(LC-ELSD)method was developed for simultaneous determination of five constituents in Xue-Fu-Zhu-Yu capsule,a widely used prescri...A reliable and accurate liquid chromatography with evaporative light scattering detection(LC-ELSD)method was developed for simultaneous determination of five constituents in Xue-Fu-Zhu-Yu capsule,a widely used prescription of traditional Chinese medicine(TCM).The chromatographic separation was performed on a Symmetry C_(18)column(150 mm×4.6 mm,5.0μm)using gradient elution of acetonitrile and water(containing 1.0%acetic acid).The flow rate was 0.6 mL/min and the temperature of column was 30℃.A good linearity correlation was obtained over the investigated concentration ranges.Recoveries of the five components varied from 97.31%to 99.84%(RSD<4.0%).The validated method was successfully applied to the quality assessment of Xue-Fu-Zhu-Yu capsule.展开更多
基金supported by Research Grant No.50908234 and No.51778634 from the National Science Foundation of China.
文摘The soil-rock mixture,a collection of soil particles and rock blocks,is inherently heterogeneous and anisotropic due to significant particle size and material strength differences.This study conducts triaxial tests on soil-rock mixture samples of various compactness subjected to varying freeze-thaw cycles.A mesoscopic simulation is carried out by particle flow code(PFC)to analyze the effects of freeze-thaw cycles on the mechanical properties of soil and rock particles.The results show that the mechanical properties of the soil-rock mixture under freeze-thaw cycles are greatly affected by the initial compaction.In general,when the degree of compaction is higher,the influence of freeze-thaw cycles on the soil-rock mixture is greater.The stress-strain curves of the samples with different compactness demonstrate strain-softening behavior.The freeze-thaw cycles greatly influence the failure strength of the samples with a higher degree of compaction but have little impact on the samples with a lower degree of compaction.On the microscopic level,during freeze-thaw cycles,the pore volume in the highly compacted sample is too small to accommodate the volume expansion from ice crystal formation,causing significant strength loss among the soil and rock particles and deterioration of the macroscopic properties of the soil-rock mixture.
基金Supported by a grant from the Medical Science and Technology Innovation Project of Shandong Academy of Medical Sciences
文摘Objective The aim of this study was to analyze and evaluate 1.32-μm and 1.06-μm neodymium-doped yttrium aluminum garnet(Nd:YAG) lasers for use in liver and gastroepiploic vessel vaporization and coagulation. Methods The effects of 1.32-μm and 1.06-μm Nd:YAG lasers were compared for gastroepiploic vessel hemostasis in porcine liver.Results The results were observed and measured under the same parameters and dose conditions. The 1.32-μm laser showed greater vaporization width and depth than the 1.06-μm laser. Both lasers controlled active bleeding. The coagulation band with the 1.32-μm laser was thinner than with the 1.06-μm laser, at nearly 3 mm. After cutting of 1-and 2-mm porcine vessels, no grossly visible bleeding was apparent. Intravascular thrombus was visible under the microscope. The length of vessel thrombosis in the experimental group was 2 mm and the diameter was 2 mm; the control group exhibited thrombi as 2.3–4.9 mm in length. Thrombosis completely blocked the blood vessels.Conclusion The 1.32-μm laser had greater vaporization capability than the 1.06-μm laser and achieved hemostasis requirements for vessels less than 2 mm in diameter.
基金The National Natural Science Foundation of China(82074069)Tianjin Municipal Science and Technology Committee(20YFZCSY00560)funded this work.
文摘Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous systems.In the past few decades,breakthrough progress has been made in the gut liver brain axis,mainly through understanding its formation mechanism and increasing treatment strategies.In this review,we discuss various complex networks including barrier permeability,gut hormones,gut microbial metabolites,vagus nerve,neurotransmitters,immunity,brain toxic metabolites,β-amyloid(Aβ)metabolism,and epigenetic regulation in the gut-liver-brain axis.Some therapies containing antibiotics,probiotics,prebiotics,synbiotics,fecal microbiota transplantation(FMT),polyphenols,low FODMAP diet and nanotechnology application regulate the gut liver brain axis.Besides,some special treatments targeting gut-liver axis include farnesoid X receptor(FXR)agonists,takeda G protein-coupled receptor 5(TGR5)agonists,glucagon-like peptide-1(GLP-1)receptor antagonists and fibroblast growth factor 19(FGF19)analogs.Targeting gut-brain axis embraces cognitive behavioral therapy(CBT),antidepressants and tryptophan metabolism-related therapies.Targeting liver-brain axis contains epigenetic regulation and Aβmetabolism-related therapies.In the future,a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.
基金supported by the National Key R&D Program of China(No.2019YFC1710604)the National Key Research and Development Program(No.2020YFA0907903)+2 种基金the key Project at Central Government Level(No.2060302)Tianjin Science and Technology Plan Project(No.19YFZCSY00170)the National Natural Science Foundation of China(No.81872956)。
文摘Objective:Pseudostellaria heterophylla has been paid more attention in recent years,mainly as a medicine food homology plant.The content determination of P.heterophylla is not specified in the Chinese Pharmacopoeia(version 2020).The environmental conditions in different production areas could exert an influence on the quality of P.heterophylla.The purpose of this study is to discriminate P.heterophylla collected from different geographical origins of China.Methods:In this study,the content of polysaccharide in 28 batches of P.heterophylla was determined using phenol–sulfuric acid.HPLC fingerprints were established under optimised HPLC-PDA methods.Subsequently,the similarity analysis(SA)and the quantification of heterophyllin B were analyzed.The metabolites of P.heterophylla were identified and evaluated using UHPLC-Q Exactive HF orbitrap MS system.Principal component analysis(PCA),partial least squares discriminant analysis(PLS-DA),hierarchical cluster analysis(HCA)and orthogonal PLS-DA(OPLS-DA)were performed based on all peak areas.Results:The polysaccharide content in Guizhou and Jiangsu was higher than that of other production areas,which varied significant from different origins.While the content of heterophyllin B in Anhui and Jiangsu was high.The correlation coefficients of HPLC fingerprints for 28 batches samples ranged from 0.877 to 0.990,and the characteristic map can be used to identify and evaluate the quality of P.heterophylla.The samples from Fujian,Guizhou,Jiangsu provinces can be relatively separated using multivariate statistical analysis including PCA,PLS-DA,HCA,OPLS-DA,indicating that their metabolic compositions were significantly different.Ultimately,a total of 15 metabolites which were filtrated by a VIPvalue>1 and a P-value<0.05 associated with the separation of different origins were identified.Conclusion:HPLC fingerprint was established to evaluate the quality and authenticity of P.heterophylla.The present work showed that the difference of geographic distributions had an influence on the internal chemical compositions.A sensitive and rapid untargeted metabolomics approach by UHPLC-Q Exactive HF orbitrap MS was utilized to evaluate P.heterophylla from different origins in China for the first time.Overall,this study provides insights to metabolomics of P.heterophylla and supplies important reference values for the development of functional foods.
基金financial support from the National Key Research and Development Program(2020YFA0907903)a key project at the central government level:“The ability to establish a sustainable use for valuable Chinese medicine resources”(2060302)+2 种基金the National Science Foundation of China(91954112 and 31900501)the Young Elite Scientists Sponsorship Program of Tianjin(TJSQNTJ-2020-19)the Scientific Research Transformation Foundation of the Wenzhou Safety(Emergency)Institute of Tianjin University。
文摘The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improve yields of Rgin a Panax ginseng chassis,combining engineering of triterpene metabolism and overexpression of a lignin biosynthesis gene,phenylalanine ammonia lyase(PAL).We first performed semi-rational design and site mutagenesis to improve the enzymatic efficiency of Pq3-O-UGT2,a glycosyltransferase that directly catalyzes the biosynthesis of Rgfrom Rh.Next,we used clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing to knock down the branch pathway of protopanaxatriol-type ginsenoside biosynthesis to enhance the metabolic flux of the protopanaxadiol-type ginsenoside Rg.Overexpression of PAL accelerated the formation of the xylem structure,significantly improving ginsenoside Rgaccumulation(to 6.19-fold higher than in thecontrol).Wecombinedoverexpression of the ginsenoside aglycon synthetic genes squalene epoxidase,Pq3-O-UGT2,and PAL with CRISPR/Cas9-based knockdown of CYP716A53v2 to improve ginsenoside Rgaccumulation.Finally,we produced ginsenoside Rgat a yield of 83.6 mg/L in a shake flask(7.0 mg/g dry weight,21.12-fold higher than with wild-type cultures).The highproduction system established in this study could be a potential platform to produce the ginsenoside Rgcommercially for pharmaceutical use.
基金financially supported by the Scientific and Technological Innovation Project Foundation of Tianjin(No.06FZZDSH00404).
文摘A reliable and accurate liquid chromatography with evaporative light scattering detection(LC-ELSD)method was developed for simultaneous determination of five constituents in Xue-Fu-Zhu-Yu capsule,a widely used prescription of traditional Chinese medicine(TCM).The chromatographic separation was performed on a Symmetry C_(18)column(150 mm×4.6 mm,5.0μm)using gradient elution of acetonitrile and water(containing 1.0%acetic acid).The flow rate was 0.6 mL/min and the temperature of column was 30℃.A good linearity correlation was obtained over the investigated concentration ranges.Recoveries of the five components varied from 97.31%to 99.84%(RSD<4.0%).The validated method was successfully applied to the quality assessment of Xue-Fu-Zhu-Yu capsule.
