Objectives: To use a novel in vitro model of three-dimensional(3D) neurosphere cultures to assess neurotoxic or neuroprotective effects with harmane as a model compound.Methods: A reproducible model of 3D spheroids wa...Objectives: To use a novel in vitro model of three-dimensional(3D) neurosphere cultures to assess neurotoxic or neuroprotective effects with harmane as a model compound.Methods: A reproducible model of 3D spheroids was developed from embryonic mouse cortical neurons,using molded agarose micro-wells;this method seems particularly practical as it is customizable and widely available and does not require specific cell treatments or assay components different from 2D cultures, allowing for the easy transposition of routine protocols. To assess the neurotoxic effects of harmane, a resazurin assay was performed to measure cell viability, and a highly sensitive fluorometric method, based on the oxidation of dichlorodihydrofluorescein, was applied to measure eventually induced reactive oxygen species(ROS) after exposure to harmane at increasing concentrations of 50 100,and 250 μm.Results: Hydrogel microwells facilitated the assembly of spheroids containing neurons and glial cells into a complex 3D structure and prevented the agglomeration of spheroids. Exposure to harmane induced cytotoxicity in 3D neural spheroids, which was correlated with harmane concentrations, with a 27%reduction in viability at 250 μm. Harmane that did not induce significant levels of oxidative stress was detected for all tested concentrations.Conclusion: This 3D neurosphere model mimics a neuronal microenvironment, allowing a fine study of neurodegenerative disorders and the effects of chemicals on the brain. This model opens novel opportunities, not only from a pathogenetic point of view but also from a therapeutic perspective.展开更多
epi-Chrysotricine 6 was synthesized by a cascade stereoselective oxidative cyclization of 5-hydroxyalkene 3 using tert-butyl hydroperoxide(TBHP) catalyzed by VO(acac)2.
(±)Chrysotricine 1 was synthesized by a facile route. The key steps in the synthesis were aldol condensation of dilithium salt of harman 4 with 6 -methyl-5-hepten-2-one 5 and cyclization of compound 6 using MCPBA...(±)Chrysotricine 1 was synthesized by a facile route. The key steps in the synthesis were aldol condensation of dilithium salt of harman 4 with 6 -methyl-5-hepten-2-one 5 and cyclization of compound 6 using MCPBA. The 1HNMR specmim of synthetic product was identical to that of the natural sample.展开更多
Rhodium oxides, including a misfitlayered structure with alternate stacking of a rock salttype layer and a hexagonal RhO2 layer, are expected to have good thermoelectric properties. Among them, the thermoelectric prop...Rhodium oxides, including a misfitlayered structure with alternate stacking of a rock salttype layer and a hexagonal RhO2 layer, are expected to have good thermoelectric properties. Among them, the thermoelectric properties (electrical conductivity (σ), Seebeck coefficient (S), Figure of merit (ZT) and calculated thermal conductivity (κ) by S, σ, ZT, and absolute temperature (T)) of bismuth-based rhodium oxides ((Bi1-x,Pbx) 2Sr2Rh2Oy, x = 0 and 0.02, hereafter BSR and BPSR, respectively) were investigated. In comparison with Bi2Sr2Co2Oy (BSC) at 700°C, S and κ enhanced (increased S, 110 (BSR) and 105 μV K-1 (BPSR) from 85 μV K-1 (BSC) and decreased κ, 0.32 (BSR) and 0.50 W m-1 K-1 (BPSR) from 1.75 W m-1 K-1 (BSC)), whereas σ decreased (15 (BSR) and 31 S cm-1 (BPSR) from 70 S cm-1 (BSC)). BPSR reached the highest ZT value of 0.067 at 700°C, compared to those of 0.056 (BSR) and 0.027 (BSC).展开更多
Thermoelectric layers as Bi<sub>2</sub>Te<sub>3</sub>, Yb<sub>0.19</sub>Co<sub>4</sub>Sb<sub>12</sub>, FeSb<sub>2</sub>Te, Ce<sub>0.1</s...Thermoelectric layers as Bi<sub>2</sub>Te<sub>3</sub>, Yb<sub>0.19</sub>Co<sub>4</sub>Sb<sub>12</sub>, FeSb<sub>2</sub>Te, Ce<sub>0.1</sub>Fe<sub>0.7</sub>Co<sub>3.3</sub>Sb<sub>12</sub> and FeSb<sub>2</sub>Te/Ce<sub>0.1</sub>Fe<sub>0.7</sub>Co<sub>3.3</sub>Sb<sub>12</sub> multilayers were prepared by Pulsed Laser Deposition (PLD). Smooth, nano-crystalline, stoichiometric layers were synthetized in a classical PLD arrangement or in a special off-axis PLD arrangement, followed by Rapid thermal annealing. Results of physical characterizations such as morphology—Atomic Force Microscope, Scanning Electron Microscope, composition-Energy Dispersive X-ray analysis, crystallinity—X-ray Diffraction, separation of multilayers—Secondary of ion beam mass spectroscopy SIMS and study of thermoelectric properties such as the thermoelectric figure of merit ZT, in-plane electrical resistivity, Seebeck coefficient and thermal conductivity are presented. For thermal conductivity measurement a newly developed Atomic force thermal microscope (AFMTh) was tested. Results obtained on the single layers compared to multi-layered structures are discussed.展开更多
Contamination by the heterocyclic aromatic amines(HAAs)norharman and harman is one of the risks in vegetable oil production,so oil producers strive to decrease their content in the end products.In this study,the effec...Contamination by the heterocyclic aromatic amines(HAAs)norharman and harman is one of the risks in vegetable oil production,so oil producers strive to decrease their content in the end products.In this study,the effects of production conditions—specifically,two pretreatment methods(roasting and microwaving),four extraction methods(two pressing and two solvent extraction)and adsorption refining(four absorbents)—of five oils(flaxseed,peanut,rapeseed,sesame,and sunflower seed)were evaluated.The results showed that microwaving as a pretreatment produced significantly fewer HAAs than roasting(P<0.05).After two pretreatments,the HAA content of oils was ranked from high to low as follows:sunflower oil,sesame oil,flaxseed oil,rapeseed oil,and peanut oil.Solvent-extracted oils(9.16–316.73μg/kg)had fewer HAAs than pressed oils(26.61–633.93μg/kg).Using adsorbents reduced HAAs in oils from the initial 21.77–484.22 to 0.31–41.58μg/kg,and the removal rate reached 99.28%.This study provides critical HAA reduction strategies for application in the oil production process to obtain safe final products.展开更多
基金funded through a Fonds Medical pour la Recherche dans le Hainaut(FMRH)granta Kangaroo grant from the UMONS Health Institute.
文摘Objectives: To use a novel in vitro model of three-dimensional(3D) neurosphere cultures to assess neurotoxic or neuroprotective effects with harmane as a model compound.Methods: A reproducible model of 3D spheroids was developed from embryonic mouse cortical neurons,using molded agarose micro-wells;this method seems particularly practical as it is customizable and widely available and does not require specific cell treatments or assay components different from 2D cultures, allowing for the easy transposition of routine protocols. To assess the neurotoxic effects of harmane, a resazurin assay was performed to measure cell viability, and a highly sensitive fluorometric method, based on the oxidation of dichlorodihydrofluorescein, was applied to measure eventually induced reactive oxygen species(ROS) after exposure to harmane at increasing concentrations of 50 100,and 250 μm.Results: Hydrogel microwells facilitated the assembly of spheroids containing neurons and glial cells into a complex 3D structure and prevented the agglomeration of spheroids. Exposure to harmane induced cytotoxicity in 3D neural spheroids, which was correlated with harmane concentrations, with a 27%reduction in viability at 250 μm. Harmane that did not induce significant levels of oxidative stress was detected for all tested concentrations.Conclusion: This 3D neurosphere model mimics a neuronal microenvironment, allowing a fine study of neurodegenerative disorders and the effects of chemicals on the brain. This model opens novel opportunities, not only from a pathogenetic point of view but also from a therapeutic perspective.
基金the National Research Center for Analysis of Drugs and Metabolites for recording NMR and MS data. This project was partially fo
文摘epi-Chrysotricine 6 was synthesized by a cascade stereoselective oxidative cyclization of 5-hydroxyalkene 3 using tert-butyl hydroperoxide(TBHP) catalyzed by VO(acac)2.
文摘(±)Chrysotricine 1 was synthesized by a facile route. The key steps in the synthesis were aldol condensation of dilithium salt of harman 4 with 6 -methyl-5-hepten-2-one 5 and cyclization of compound 6 using MCPBA. The 1HNMR specmim of synthetic product was identical to that of the natural sample.
文摘Rhodium oxides, including a misfitlayered structure with alternate stacking of a rock salttype layer and a hexagonal RhO2 layer, are expected to have good thermoelectric properties. Among them, the thermoelectric properties (electrical conductivity (σ), Seebeck coefficient (S), Figure of merit (ZT) and calculated thermal conductivity (κ) by S, σ, ZT, and absolute temperature (T)) of bismuth-based rhodium oxides ((Bi1-x,Pbx) 2Sr2Rh2Oy, x = 0 and 0.02, hereafter BSR and BPSR, respectively) were investigated. In comparison with Bi2Sr2Co2Oy (BSC) at 700°C, S and κ enhanced (increased S, 110 (BSR) and 105 μV K-1 (BPSR) from 85 μV K-1 (BSC) and decreased κ, 0.32 (BSR) and 0.50 W m-1 K-1 (BPSR) from 1.75 W m-1 K-1 (BSC)), whereas σ decreased (15 (BSR) and 31 S cm-1 (BPSR) from 70 S cm-1 (BSC)). BPSR reached the highest ZT value of 0.067 at 700°C, compared to those of 0.056 (BSR) and 0.027 (BSC).
文摘Thermoelectric layers as Bi<sub>2</sub>Te<sub>3</sub>, Yb<sub>0.19</sub>Co<sub>4</sub>Sb<sub>12</sub>, FeSb<sub>2</sub>Te, Ce<sub>0.1</sub>Fe<sub>0.7</sub>Co<sub>3.3</sub>Sb<sub>12</sub> and FeSb<sub>2</sub>Te/Ce<sub>0.1</sub>Fe<sub>0.7</sub>Co<sub>3.3</sub>Sb<sub>12</sub> multilayers were prepared by Pulsed Laser Deposition (PLD). Smooth, nano-crystalline, stoichiometric layers were synthetized in a classical PLD arrangement or in a special off-axis PLD arrangement, followed by Rapid thermal annealing. Results of physical characterizations such as morphology—Atomic Force Microscope, Scanning Electron Microscope, composition-Energy Dispersive X-ray analysis, crystallinity—X-ray Diffraction, separation of multilayers—Secondary of ion beam mass spectroscopy SIMS and study of thermoelectric properties such as the thermoelectric figure of merit ZT, in-plane electrical resistivity, Seebeck coefficient and thermal conductivity are presented. For thermal conductivity measurement a newly developed Atomic force thermal microscope (AFMTh) was tested. Results obtained on the single layers compared to multi-layered structures are discussed.
基金This work was funded in part by the earmarked fund for China Agriculture Research system of MOF and MARA(No.CARS-14)the Central Government-Guided Local S&T Development Fund Project of Henan(No.Z20221343038)the Key Research and Development Project of Henan Province(No.221111520400),China.
文摘Contamination by the heterocyclic aromatic amines(HAAs)norharman and harman is one of the risks in vegetable oil production,so oil producers strive to decrease their content in the end products.In this study,the effects of production conditions—specifically,two pretreatment methods(roasting and microwaving),four extraction methods(two pressing and two solvent extraction)and adsorption refining(four absorbents)—of five oils(flaxseed,peanut,rapeseed,sesame,and sunflower seed)were evaluated.The results showed that microwaving as a pretreatment produced significantly fewer HAAs than roasting(P<0.05).After two pretreatments,the HAA content of oils was ranked from high to low as follows:sunflower oil,sesame oil,flaxseed oil,rapeseed oil,and peanut oil.Solvent-extracted oils(9.16–316.73μg/kg)had fewer HAAs than pressed oils(26.61–633.93μg/kg).Using adsorbents reduced HAAs in oils from the initial 21.77–484.22 to 0.31–41.58μg/kg,and the removal rate reached 99.28%.This study provides critical HAA reduction strategies for application in the oil production process to obtain safe final products.
