L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well...L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well explained.Given the complexity of the pathogenesis of depression,this study investigated the preventive effect and mechanism of L-theanine on depression in juvenile rats by combining serum and hippocampal metabolomic strategies.Behavioral tests,hippocampal tissue sections,and serum and hippocampal biochemical indexes were studied,and the results confirmed the preventive effect of Ltheanine.Untargeted reversed-phase liquid chromatography-quadrupole-time-of-flight mass spectrometry and targeted hydrophilic interaction liquid chromatography-triple quadrupole mass spectrometry were developed to analyze the metabolism changes in the serum and hippocampus to screen for potential biomarkers related to L-theanine treatment.The results suggested that 28 abnormal metabolites in the serum and hippocampus that were considered as potential biomarkers returned to nearnormal levels after L-theanine administration.These biomarkers were involved in various metabolic pathways,mainly including amino acid metabolism and lipid metabolism.The levels of amino acids and neurotransmitters in the phenylalanine,tryptophan,and glutamic acid pathways were significantly reduced after L-theanine administration compared with chronic unpredictable mild stress-induced rats.In summary,L-theanine had a significant preventive effect on depression and achieved its preventive results on depression by regulating various aspects of the body,such as amino acids,lipids,and inflammation.This research systematically analyzed the mechanism of L-theanine in preventing depression and laid the foundation for applying L-theanine to prevent depression in children and adolescents.展开更多
The thermo-physical properties of nanofluids are highly dependent on the used base fluid.This study explores the influence of the mixing ratio on the thermal conductivity and viscosity of ZnO-CuO/EG(ethylene glycol)-W...The thermo-physical properties of nanofluids are highly dependent on the used base fluid.This study explores the influence of the mixing ratio on the thermal conductivity and viscosity of ZnO-CuO/EG(ethylene glycol)-W(water)hybrid nanofluids with mass concentration and temperatures in the ranges 1-5 wt.%and 25-60C,respectively.The characteristics and stability of these mixtures were estimated by TEM(transmission electron microscopy),visual observation,and absorbance tests.The results show that 120 min of sonication and the addition of PVP(polyvinyl pyrrolidone)surfactant can prevent sedimentation for a period reaching up to 20 days.The increase of EG(ethylene glycol)in the base fluid leads to low thermal conductivity and high viscosity.Thermal conductivity enhancement(TCE)decreases from 21.52%to 11.7%when EG:W is changed from 20:80 to 80:20 at 1 wt.%and 60C.A lower viscosity of the base fluid influences more significantly the TCE of the nanofluid.An Artificial Neural Network(ANN)has also been used to describe the effectiveness of these hybrid nanofluids as heat transfer fluids.The optimal number of layers and neurons in these models have been found to be 1 and 5 for viscosity,and 1 and 7 for thermal conductivity.The corresponding coefficient of determination(R^(2))was 0.9979 and 0.9989,respectively.展开更多
To the Editor:Acute myocardial infarction(AMI)poses a substantial threat to human health.^([1])At present,AMI is mainly treated by reperfusion,drugs,and surgery,^([2])which only temporarily delay cell death and deteri...To the Editor:Acute myocardial infarction(AMI)poses a substantial threat to human health.^([1])At present,AMI is mainly treated by reperfusion,drugs,and surgery,^([2])which only temporarily delay cell death and deterioration.Sian Harding at el^([3])suggested that myocardial transfer of specific bone marrow cells(BMCs)and progenitor cell populations may enhance recovery of systolic and diastolic function after AMI.Although a few previous meta-analysis studies of BMCs transplantation for AMI have been published,the quality of these studies was varied due to marked heterogeneity^([4,5])or because they focused on a single outcome(e.g.,cardiac function)[5]and very few evaluated the clinical evens.^([6])In addition,the effects of BMCs transplantation over different lengths of follow-up periods were unclear.In an attempt to reach more reliable conclusions,we performed an updated meta-analysis of randomized controlled trials(RCTs)and conducted subgroup analyses according to follow-up periods.展开更多
文摘L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well explained.Given the complexity of the pathogenesis of depression,this study investigated the preventive effect and mechanism of L-theanine on depression in juvenile rats by combining serum and hippocampal metabolomic strategies.Behavioral tests,hippocampal tissue sections,and serum and hippocampal biochemical indexes were studied,and the results confirmed the preventive effect of Ltheanine.Untargeted reversed-phase liquid chromatography-quadrupole-time-of-flight mass spectrometry and targeted hydrophilic interaction liquid chromatography-triple quadrupole mass spectrometry were developed to analyze the metabolism changes in the serum and hippocampus to screen for potential biomarkers related to L-theanine treatment.The results suggested that 28 abnormal metabolites in the serum and hippocampus that were considered as potential biomarkers returned to nearnormal levels after L-theanine administration.These biomarkers were involved in various metabolic pathways,mainly including amino acid metabolism and lipid metabolism.The levels of amino acids and neurotransmitters in the phenylalanine,tryptophan,and glutamic acid pathways were significantly reduced after L-theanine administration compared with chronic unpredictable mild stress-induced rats.In summary,L-theanine had a significant preventive effect on depression and achieved its preventive results on depression by regulating various aspects of the body,such as amino acids,lipids,and inflammation.This research systematically analyzed the mechanism of L-theanine in preventing depression and laid the foundation for applying L-theanine to prevent depression in children and adolescents.
基金This project is supported by Yulingn Zhai and the National Natural Science Foundation of China(No.51806090)the Basic Research Project of Yunnan Province(No.202001AT070081).
文摘The thermo-physical properties of nanofluids are highly dependent on the used base fluid.This study explores the influence of the mixing ratio on the thermal conductivity and viscosity of ZnO-CuO/EG(ethylene glycol)-W(water)hybrid nanofluids with mass concentration and temperatures in the ranges 1-5 wt.%and 25-60C,respectively.The characteristics and stability of these mixtures were estimated by TEM(transmission electron microscopy),visual observation,and absorbance tests.The results show that 120 min of sonication and the addition of PVP(polyvinyl pyrrolidone)surfactant can prevent sedimentation for a period reaching up to 20 days.The increase of EG(ethylene glycol)in the base fluid leads to low thermal conductivity and high viscosity.Thermal conductivity enhancement(TCE)decreases from 21.52%to 11.7%when EG:W is changed from 20:80 to 80:20 at 1 wt.%and 60C.A lower viscosity of the base fluid influences more significantly the TCE of the nanofluid.An Artificial Neural Network(ANN)has also been used to describe the effectiveness of these hybrid nanofluids as heat transfer fluids.The optimal number of layers and neurons in these models have been found to be 1 and 5 for viscosity,and 1 and 7 for thermal conductivity.The corresponding coefficient of determination(R^(2))was 0.9979 and 0.9989,respectively.
基金supported by grants from the National Natural Science Foundation of China(No.81960614)International scientific and technological cooperation project(No.20YF3WA020).
文摘To the Editor:Acute myocardial infarction(AMI)poses a substantial threat to human health.^([1])At present,AMI is mainly treated by reperfusion,drugs,and surgery,^([2])which only temporarily delay cell death and deterioration.Sian Harding at el^([3])suggested that myocardial transfer of specific bone marrow cells(BMCs)and progenitor cell populations may enhance recovery of systolic and diastolic function after AMI.Although a few previous meta-analysis studies of BMCs transplantation for AMI have been published,the quality of these studies was varied due to marked heterogeneity^([4,5])or because they focused on a single outcome(e.g.,cardiac function)[5]and very few evaluated the clinical evens.^([6])In addition,the effects of BMCs transplantation over different lengths of follow-up periods were unclear.In an attempt to reach more reliable conclusions,we performed an updated meta-analysis of randomized controlled trials(RCTs)and conducted subgroup analyses according to follow-up periods.