The tobacco whitefly,Bemisia tabaci,is a notorious pest affecting various crops globally,and it exhibits high levels of resistance to various insecticides.Afidopyropen is a recently commercialized pyropene insecticide...The tobacco whitefly,Bemisia tabaci,is a notorious pest affecting various crops globally,and it exhibits high levels of resistance to various insecticides.Afidopyropen is a recently commercialized pyropene insecticide for B.tabaci control with high selectivity and a novel mode of action.We previously identified a high level of afidopyropen resistance in a field-collected population after selection in the lab,and named it the HD-Afi strain.In the present study,minimal cross-resistance in the HD-Afi strain was found between afidopyropen and other common chemical agents.However,the P450 enzyme activity in HD-Afi was 2.18 times the level in susceptible strain HD-S.Expression analysis revealed that two of 12 candidate P450 genes,namely CYP6DW3 and CYP4C64,were significantly up-regulated in HD-Afi.Silencing CYP6DW3 and CYP4C64 by RNA interference(RNAi)substantially increased the susceptibility of whitefly adults,confirming their involvement in afidopyropen resistance.Homology modeling and molecular docking analyses demonstrated stable binding of afidopyropen to CYP6DW3 and CYP4C64,with binding free energies of–6.87 and–6.11 kcal mol^(-1),respectively.The findings of this study suggest that the induction of CYP6DW3 and CYP4C64 facilitates afidopyropen detoxification,contributing to the development of resistance in B.tabaci.展开更多
BACKGROUND Decreased serum magnesium(Mg2+)is commonly seen in critically ill patients.Hypomagnesemia is significantly more frequent in patients with severe acute pancreatitis.Acute kidney injury(AKI)in patients with a...BACKGROUND Decreased serum magnesium(Mg2+)is commonly seen in critically ill patients.Hypomagnesemia is significantly more frequent in patients with severe acute pancreatitis.Acute kidney injury(AKI)in patients with acute pancreatitis(AP)is associated with an extremely high mortality.The association underlying serum Mg2+and AKI in AP has not been elucidated.AIM To explore the association between serum Mg2+on admission and AKI in patients with AP.METHODS A retrospective observational study was conducted in a cohort of patients(n=233)with AP without any renal injury before admission to our center from August 2015 to February 2019.Demographic characteristics on admission,severity score,laboratory values and in-hospital mortality were compared between patients with and without AKI.RESULTS A total of 233 patients were included for analysis,including 85 with AKI.Compared to patients without AKI,serum Mg2+level was significantly lower in patients with AKI at admission[OR=6.070,95%CI:3.374-10.921,P<0.001].Multivariate logistic analysis showed that lower serum Mg2+was an independent risk factor for AKI[OR=8.47,95%CI:3.02-23.72,P<0.001].CONCLUSION Our analysis indicates that serum Mg2+level at admission is independently associated with the development of AKI in patients with AP and may be a potential prognostic factor.展开更多
Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. ...Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.展开更多
Objective:Ginkgo biloba leaves,as an herbal medicine or dietary supplement,have been widely used worldwide.In this study,an integrated analytical method was established for the comprehensive analysis of flavonoids in ...Objective:Ginkgo biloba leaves,as an herbal medicine or dietary supplement,have been widely used worldwide.In this study,an integrated analytical method was established for the comprehensive analysis of flavonoids in G.biloba leaves.Materials and Methods:A practical chromatographic method combining high-performance liquid chromatography fingerprint analysis and quantitation was used to simultaneously determine 11 flavonoids(6 flavonol glycosides and 5 biflavones)in G.biloba leaves from different regions.Results:A total of 11 characteristic peaks were identified accurately,and the similarity of fingerprints ranged from 0.944 to 0.996.Methodology validation revealed appropriate linearity(R^(2)≥0.9997),precision,repeatability,stability,and recovery.The total contents of the six flavonol glycosides and five biflavones were within the range of 2.142-8.378 mg/g and 3.759-5.675 mg/g in 19 batches of samples,respectively.Among them,two coumaroyl flavonol glycosides were the predominant components.Conclusions:In this study,a convenient and reliable approach was successfully employed for the comprehensive evaluation of flavonoids in G.biloba leaves,which also provided a reference for its quality standard.展开更多
Abundant high-performance organic crystals have been reported in the past decades;however,applications of crystalline materials are seriously restricted by their notorious brittleness.Recently,some organic crystals ha...Abundant high-performance organic crystals have been reported in the past decades;however,applications of crystalline materials are seriously restricted by their notorious brittleness.Recently,some organic crystals have been designed to be deformable in response to stress,light,heat,or humidity;nevertheless,the development of flexible organic crystals currently relies on a molecular framework design.So far there is no effective strategy for constructing organic crystals with tunable flexibility based on the same luminescent skeleton.Herein,we propose a side-chain engineering strategy aimed at facilely modulating the mechanical compliance of organic crystals.Subtly changing the side chains of a single-benzeneπ-skeleton greatly alters the mechanical behaviors while maintaining the unique optical functions of the produced crystals.Optical waveguides and amplified spontaneous emissions were measured to evaluate the application potentials of the flexible crystals as soft optical transducing media.We anticipate that the proposed strategy will be expanded to regulate the mechanical compliance of other organic crystals with unique emission properties.In addition,the applications attempted preliminarily here highlight the superiority of“crystal flexibility”in flexible optoelectronics for some special application scenarios that require complex and shape changeable optical circuits.展开更多
Fatty acyl reductases(FARs)are key enzymes that participate in sex pheromone biosynthesis by reducing fatty acids to fatty alcohols.Lepidoptera typically harbor numerous FAR gene family members.Although FAR genes are ...Fatty acyl reductases(FARs)are key enzymes that participate in sex pheromone biosynthesis by reducing fatty acids to fatty alcohols.Lepidoptera typically harbor numerous FAR gene family members.Although FAR genes are involved in the biosynthesis of sex pheromones in moths,the key FAR gene of Spodoptera litura remains unclear.In this work,we predicted 30 FAR genes from the S.litura genome and identified a domain duplication within gene SlitFAR3,which exhibited high and preferential expression in the sexually mature female pheromone glands(PGs)and a rhythmic expression pattern during the scotophase of sex pheromone production.The molecular docking of SlitFAR3,as predicted using a 3D model,revealed a co-factor NADPH binding cavity and 2 substrate binding cavities.Functional expression in yeast cells combined with comprehensive gas chromatography indicated that the SlitFAR3 gene could produce fatty alcohol products.This study is the first to focus on the special phenomenon of FAR domain duplication,which will advance our understanding of biosynthesis-related genes from the perspective of evolutionary biology.展开更多
基金partly supported by research grants from the Outstanding Youth Foundation of the Beijing Academy of Agriculture and Forestry Sciences,China(YXQN202301)the National Natural Science Foundation of China(32272522)the Beijing Natural Science Foundation,China(6232005)。
文摘The tobacco whitefly,Bemisia tabaci,is a notorious pest affecting various crops globally,and it exhibits high levels of resistance to various insecticides.Afidopyropen is a recently commercialized pyropene insecticide for B.tabaci control with high selectivity and a novel mode of action.We previously identified a high level of afidopyropen resistance in a field-collected population after selection in the lab,and named it the HD-Afi strain.In the present study,minimal cross-resistance in the HD-Afi strain was found between afidopyropen and other common chemical agents.However,the P450 enzyme activity in HD-Afi was 2.18 times the level in susceptible strain HD-S.Expression analysis revealed that two of 12 candidate P450 genes,namely CYP6DW3 and CYP4C64,were significantly up-regulated in HD-Afi.Silencing CYP6DW3 and CYP4C64 by RNA interference(RNAi)substantially increased the susceptibility of whitefly adults,confirming their involvement in afidopyropen resistance.Homology modeling and molecular docking analyses demonstrated stable binding of afidopyropen to CYP6DW3 and CYP4C64,with binding free energies of–6.87 and–6.11 kcal mol^(-1),respectively.The findings of this study suggest that the induction of CYP6DW3 and CYP4C64 facilitates afidopyropen detoxification,contributing to the development of resistance in B.tabaci.
基金National Natural Science Foundation of China,No.82070669.
文摘BACKGROUND Decreased serum magnesium(Mg2+)is commonly seen in critically ill patients.Hypomagnesemia is significantly more frequent in patients with severe acute pancreatitis.Acute kidney injury(AKI)in patients with acute pancreatitis(AP)is associated with an extremely high mortality.The association underlying serum Mg2+and AKI in AP has not been elucidated.AIM To explore the association between serum Mg2+on admission and AKI in patients with AP.METHODS A retrospective observational study was conducted in a cohort of patients(n=233)with AP without any renal injury before admission to our center from August 2015 to February 2019.Demographic characteristics on admission,severity score,laboratory values and in-hospital mortality were compared between patients with and without AKI.RESULTS A total of 233 patients were included for analysis,including 85 with AKI.Compared to patients without AKI,serum Mg2+level was significantly lower in patients with AKI at admission[OR=6.070,95%CI:3.374-10.921,P<0.001].Multivariate logistic analysis showed that lower serum Mg2+was an independent risk factor for AKI[OR=8.47,95%CI:3.02-23.72,P<0.001].CONCLUSION Our analysis indicates that serum Mg2+level at admission is independently associated with the development of AKI in patients with AP and may be a potential prognostic factor.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.20274028,50373030 and 20490220)This work is also partly supported by Ministry of Education of China for Doctoral Degree(No.20020610004).
文摘Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.
基金the financial support from the National Natural Science Foundation of China(No.81722048)。
文摘Objective:Ginkgo biloba leaves,as an herbal medicine or dietary supplement,have been widely used worldwide.In this study,an integrated analytical method was established for the comprehensive analysis of flavonoids in G.biloba leaves.Materials and Methods:A practical chromatographic method combining high-performance liquid chromatography fingerprint analysis and quantitation was used to simultaneously determine 11 flavonoids(6 flavonol glycosides and 5 biflavones)in G.biloba leaves from different regions.Results:A total of 11 characteristic peaks were identified accurately,and the similarity of fingerprints ranged from 0.944 to 0.996.Methodology validation revealed appropriate linearity(R^(2)≥0.9997),precision,repeatability,stability,and recovery.The total contents of the six flavonol glycosides and five biflavones were within the range of 2.142-8.378 mg/g and 3.759-5.675 mg/g in 19 batches of samples,respectively.Among them,two coumaroyl flavonol glycosides were the predominant components.Conclusions:In this study,a convenient and reliable approach was successfully employed for the comprehensive evaluation of flavonoids in G.biloba leaves,which also provided a reference for its quality standard.
基金supported by the National Natural Science Foundation of China(grant no.52173164).
文摘Abundant high-performance organic crystals have been reported in the past decades;however,applications of crystalline materials are seriously restricted by their notorious brittleness.Recently,some organic crystals have been designed to be deformable in response to stress,light,heat,or humidity;nevertheless,the development of flexible organic crystals currently relies on a molecular framework design.So far there is no effective strategy for constructing organic crystals with tunable flexibility based on the same luminescent skeleton.Herein,we propose a side-chain engineering strategy aimed at facilely modulating the mechanical compliance of organic crystals.Subtly changing the side chains of a single-benzeneπ-skeleton greatly alters the mechanical behaviors while maintaining the unique optical functions of the produced crystals.Optical waveguides and amplified spontaneous emissions were measured to evaluate the application potentials of the flexible crystals as soft optical transducing media.We anticipate that the proposed strategy will be expanded to regulate the mechanical compliance of other organic crystals with unique emission properties.In addition,the applications attempted preliminarily here highlight the superiority of“crystal flexibility”in flexible optoelectronics for some special application scenarios that require complex and shape changeable optical circuits.
基金China Agriculture Research System of MOF and MARA(CARS-24-C-03)National Key R&D Program of China(Grant no.2019YFD1002100).
文摘Fatty acyl reductases(FARs)are key enzymes that participate in sex pheromone biosynthesis by reducing fatty acids to fatty alcohols.Lepidoptera typically harbor numerous FAR gene family members.Although FAR genes are involved in the biosynthesis of sex pheromones in moths,the key FAR gene of Spodoptera litura remains unclear.In this work,we predicted 30 FAR genes from the S.litura genome and identified a domain duplication within gene SlitFAR3,which exhibited high and preferential expression in the sexually mature female pheromone glands(PGs)and a rhythmic expression pattern during the scotophase of sex pheromone production.The molecular docking of SlitFAR3,as predicted using a 3D model,revealed a co-factor NADPH binding cavity and 2 substrate binding cavities.Functional expression in yeast cells combined with comprehensive gas chromatography indicated that the SlitFAR3 gene could produce fatty alcohol products.This study is the first to focus on the special phenomenon of FAR domain duplication,which will advance our understanding of biosynthesis-related genes from the perspective of evolutionary biology.
