To study insecticidal mechanism of terpinen-4-ol, a main insecticidal composition in the essential oil of Sabina vulgaris, the 5th instar larvae of Mythimna separta, were investigated with terpinen-4-ol by topical app...To study insecticidal mechanism of terpinen-4-ol, a main insecticidal composition in the essential oil of Sabina vulgaris, the 5th instar larvae of Mythimna separta, were investigated with terpinen-4-ol by topical application. The activities of phosphatase, glutathione S-transferase （GSTs）, cytochrome P450 （P450）, and polyphenol oxidase （PPO） of tested insects were determined in all poisoning stages, including exciting stage, convulsing stage, paralysis stage, and recover stage. The result showed that the activities of both acid phosphatase （ACP） and alkaline phosphatase （AKP） in treated insects were induced by terpinen-4-ol, but ACP was inhibited in paralysis stage. The activities of GSTs were inhibited in exciting stage, convulsing stage, and paralysis stage, but gradually recovered in recover stage. O-demethylase activity of cytochrome P450 was inhibited by terpinen-4-ol, and the inhibition rate in all poisoning stages were 26.27, 46.03, 80.24, and 90.22%, respectively. PPO activities were strongly inhibited by terpinen-4-ol both in vitro and in vivo. In conclusion, the activities of P450, GSTs, and PPO could have relation with toxicity of terpinen-4-ol against larvae of the Mythimna separta, but recover stage of the poisoning insects might be related to GSTs induced. As a new insecticide or synergist, terpinen- 4-ol has a potential value in field of insecticide resistance management.展开更多
To reveal the insecticidal mechanism of terpinen-4-ol, the activity of Na＋,K＋-ATPase in insects tested were determined in vivo and in vitro. The results showed that terpinen-4-ol and its ester derivatives had strong...To reveal the insecticidal mechanism of terpinen-4-ol, the activity of Na＋,K＋-ATPase in insects tested were determined in vivo and in vitro. The results showed that terpinen-4-ol and its ester derivatives had strong contact activity to housefly and the contact toxicities of its derivatives except Z3 were all superior or equivalent to terpinen-4-ol. All the 7 compounds had strong inhibition towards activity of Na＋,K＋-ATPase. With poisoning symptom exacerbating, the inhibition rates were gradually increased. In vitro, the IC50 of terpinen-4-ol, Z1, Z2, Z4, Z5, and Z6 was 155.89, 197.98, 96.02, 121.36, 124.85, and 153.74 μg mL% respectively. There was well correlation between the LDs0 of terpinen-4-ol derivatives to housefly and the IC50 of terpinen-4-ol derivatives to Na＋,K＋-ATPase in housefly. In conclusion, Na＋,K＋-ATPase was likely the target of terpinen-4-ol against insects.展开更多
Dimethyldichlorosilane is a basic raw material for preparing a variety of organosilicon materials.The disproportionation method to synthesize it can solve the problem brought by direct synthesis.The B3LYP/6-31G and MP...Dimethyldichlorosilane is a basic raw material for preparing a variety of organosilicon materials.The disproportionation method to synthesize it can solve the problem brought by direct synthesis.The B3LYP/6-31G and MP2/6-311++G(3df,2pd) methods were used to calculate the mechanism of the reaction catalyzed by localized core(4 T)-shell catalyst.The energy barriers of the rate-determining steps of the main reaction at different active sites 1(5)~4 in the HZSM-5(4T)@γ-Al2O3 catalyst were 165.88,129.99,118.66 and 145.55 kJ·mol-1,respectively,and those in the side reaction are 131.98,146.28,146.53 and 164.17 kJ·mol-1,separately.The active site No.3 was the easiest one to participate in the catalytic reaction.The energy barriers of the rate-determining steps of the main reaction catalyzed by the AlCl3/HZSM-5(4T)@γ-Al2O3 catalyst,involving configurations a and b,are 105.12 and 110.39 kJ·mol-1,respectively,and those of the side reaction are 144.26 and 159.55 kJ·mol-1,respectively.Both configurations produced dimethyldichlorosilane mainly,and configuration a is easier to catalyze the reaction process.And according to the bond order and locality analysis,the catalytic activity order was:configuration a>configuration b.This conclusion matched with the reaction energy barrier analysis.The AlCl3/HZSM-5(4T)@γ-Al2O3 catalyst had a better catalytic activity than HZSM-5(4T)@γ-Al2O3.The active center of the reaction system of HZSM-5(4T)@γ-Al2O3 was proton,Bronsted acidic center,and that of AlCl3/HZSM-5@γ-Al2O3 could be Lewis acidic center.The source of the Lewis acidic center was the multi-center bond formed by the delocalization of peripheral electrons of the atoms.The frontier orbital theory confirmed the mechanism and good selectivity of the reaction.展开更多
Peptide-functionalized Au-Fe2O3 nanoparticles（termed as anti-CXCR4-Au-Fe2O3 NPs） have been constructed through conjugation of dumbbell-like Au-Fe203 NPs with C-X-C motif chemokine receptor 4（CXCR4） binding cyclic ...Peptide-functionalized Au-Fe2O3 nanoparticles（termed as anti-CXCR4-Au-Fe2O3 NPs） have been constructed through conjugation of dumbbell-like Au-Fe203 NPs with C-X-C motif chemokine receptor 4（CXCR4） binding cyclic peptide. One dumbbelMike Au-Fe2O3NP composes an Au NP[（3.3±0.3） nm in diameter] for conjugating CXCR4 binding cyclic peptide through Au-S covalent bond and a Fe2O3 NP[（8.7±0.8） nm in diameter] for using as T2-weighted magnetic resonance imaging（MRI） contrast agent. The anti-CXCR4-Au-Fe2O3 NPs have reasonable biocompatibility and integration of T2-weighted MRI contrast and tumor-targeting functionalities. The anti- CXCR4-Au-Fe2O3 NPs exhibit strong interactions with two kinds of breast tumor cells, MCF-7 cells and MDA-MB-231 cells, and high negative contrast in MRI of MDA-MB-231 tumor bearing mouse with 62% decreasing of MRI signal, indicating that the anti-CXCR4-Au-Fe2O3 NPs can recognize tumor with high efficacy and specificity.展开更多
Over the past few decades,complementary and alternative treatments have become increasingly popular worldwide.The purported therapeutic characteristics of natural products have come under increased scrutiny both in vi...Over the past few decades,complementary and alternative treatments have become increasingly popular worldwide.The purported therapeutic characteristics of natural products have come under increased scrutiny both in vitro and in vivo as part of efforts to legitimize their usage.One such product is tea tree oil(TTO),a volatile essential oil primarily obtained from the native Australian plant,Melaleuca alternifolia,which has diverse traditional and industrial applications such as topical preparations for the treatment of skin infections.Its anti-inflammatory-linked immunomodulatory actions have also been reported.This systematic review focuses on the anti-inflammatory effects of TTO and its main components that have shown strong immunomodulatory potential.An extensive literature search was performed electronically for data curation on worldwide accepted scientific databases,such as Web of Science,Google Scholar,PubMed,ScienceDirect,Scopus,and esteemed publishers such as Elsevier,Springer,Frontiers,and Taylor&Francis.Considering that the majority of pharmacological studies were conducted on crude oils only,the extracted data were critically analyzed to gain further insight into the prospects of TTO being used as a neuroprotective agent by drug formulation or dietary supplement.In addition,the active constituents contributing to the activity of TTO have not been well justified,and the core mechanisms need to be unveiled especially for anti-inflammatory and immunomodulatory effects leading to neuroprotection.Therefore,this review attempts to correlate the anti-inflammatory and immunomodulatory activity of TTO with its neuroprotective mechanisms.展开更多
以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为9...以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为95.4%和96.7%;利用FT-IR、1 H NMR、13C NMR、15 N NMR及元素分析等方法对其结构进行表征;采用量子化学方法计算了3-ATDNMNT和4-ATDNMNT的爆轰性能;在标准状态下(膨胀比为70∶1),利用最小自由能原理,分别计算了两种离子盐在丁羟复合推进剂中的能量性能。结果表明,3-ATDNMNT的爆速和爆压分别为8.587km/s和33.58GPa,4-ATDNMNT的爆速和爆压分别为8.693km/s和34.31GPa。以3-ATDNMNT部分取代丁羟复合推进剂中的AP后,丁羟复合推进剂的理论比冲可达2 635.7N·s/kg。以4-ATDNMNT部分取代丁羟复合推进剂中的AP后,当HTPB、Al、AP及4-ATDNMNT各组分质量分数分别为10%、5%、15%及70%时,获得该丁羟复合推进剂的最高理论比冲为2 677.2N·s/kg。展开更多
基金supported by the National Natural Science Foundation of China(30600404)the Key Technologies R&D Program of China during the 10th Five-Year Plan Period(2004BA516A04).
文摘To study insecticidal mechanism of terpinen-4-ol, a main insecticidal composition in the essential oil of Sabina vulgaris, the 5th instar larvae of Mythimna separta, were investigated with terpinen-4-ol by topical application. The activities of phosphatase, glutathione S-transferase （GSTs）, cytochrome P450 （P450）, and polyphenol oxidase （PPO） of tested insects were determined in all poisoning stages, including exciting stage, convulsing stage, paralysis stage, and recover stage. The result showed that the activities of both acid phosphatase （ACP） and alkaline phosphatase （AKP） in treated insects were induced by terpinen-4-ol, but ACP was inhibited in paralysis stage. The activities of GSTs were inhibited in exciting stage, convulsing stage, and paralysis stage, but gradually recovered in recover stage. O-demethylase activity of cytochrome P450 was inhibited by terpinen-4-ol, and the inhibition rate in all poisoning stages were 26.27, 46.03, 80.24, and 90.22%, respectively. PPO activities were strongly inhibited by terpinen-4-ol both in vitro and in vivo. In conclusion, the activities of P450, GSTs, and PPO could have relation with toxicity of terpinen-4-ol against larvae of the Mythimna separta, but recover stage of the poisoning insects might be related to GSTs induced. As a new insecticide or synergist, terpinen- 4-ol has a potential value in field of insecticide resistance management.
基金supported by the National Natural Science Foundation of China (30600404)
文摘To reveal the insecticidal mechanism of terpinen-4-ol, the activity of Na＋,K＋-ATPase in insects tested were determined in vivo and in vitro. The results showed that terpinen-4-ol and its ester derivatives had strong contact activity to housefly and the contact toxicities of its derivatives except Z3 were all superior or equivalent to terpinen-4-ol. All the 7 compounds had strong inhibition towards activity of Na＋,K＋-ATPase. With poisoning symptom exacerbating, the inhibition rates were gradually increased. In vitro, the IC50 of terpinen-4-ol, Z1, Z2, Z4, Z5, and Z6 was 155.89, 197.98, 96.02, 121.36, 124.85, and 153.74 μg mL% respectively. There was well correlation between the LDs0 of terpinen-4-ol derivatives to housefly and the IC50 of terpinen-4-ol derivatives to Na＋,K＋-ATPase in housefly. In conclusion, Na＋,K＋-ATPase was likely the target of terpinen-4-ol against insects.
基金financially supported by the National Natural Science Foundation of China (Nos. 21563011 and 21872049)。
文摘Dimethyldichlorosilane is a basic raw material for preparing a variety of organosilicon materials.The disproportionation method to synthesize it can solve the problem brought by direct synthesis.The B3LYP/6-31G and MP2/6-311++G(3df,2pd) methods were used to calculate the mechanism of the reaction catalyzed by localized core(4 T)-shell catalyst.The energy barriers of the rate-determining steps of the main reaction at different active sites 1(5)~4 in the HZSM-5(4T)@γ-Al2O3 catalyst were 165.88,129.99,118.66 and 145.55 kJ·mol-1,respectively,and those in the side reaction are 131.98,146.28,146.53 and 164.17 kJ·mol-1,separately.The active site No.3 was the easiest one to participate in the catalytic reaction.The energy barriers of the rate-determining steps of the main reaction catalyzed by the AlCl3/HZSM-5(4T)@γ-Al2O3 catalyst,involving configurations a and b,are 105.12 and 110.39 kJ·mol-1,respectively,and those of the side reaction are 144.26 and 159.55 kJ·mol-1,respectively.Both configurations produced dimethyldichlorosilane mainly,and configuration a is easier to catalyze the reaction process.And according to the bond order and locality analysis,the catalytic activity order was:configuration a>configuration b.This conclusion matched with the reaction energy barrier analysis.The AlCl3/HZSM-5(4T)@γ-Al2O3 catalyst had a better catalytic activity than HZSM-5(4T)@γ-Al2O3.The active center of the reaction system of HZSM-5(4T)@γ-Al2O3 was proton,Bronsted acidic center,and that of AlCl3/HZSM-5@γ-Al2O3 could be Lewis acidic center.The source of the Lewis acidic center was the multi-center bond formed by the delocalization of peripheral electrons of the atoms.The frontier orbital theory confirmed the mechanism and good selectivity of the reaction.
基金Supported by the National Natural Science Foundation of China（No.80151459）.
文摘Peptide-functionalized Au-Fe2O3 nanoparticles（termed as anti-CXCR4-Au-Fe2O3 NPs） have been constructed through conjugation of dumbbell-like Au-Fe203 NPs with C-X-C motif chemokine receptor 4（CXCR4） binding cyclic peptide. One dumbbelMike Au-Fe2O3NP composes an Au NP[（3.3±0.3） nm in diameter] for conjugating CXCR4 binding cyclic peptide through Au-S covalent bond and a Fe2O3 NP[（8.7±0.8） nm in diameter] for using as T2-weighted magnetic resonance imaging（MRI） contrast agent. The anti-CXCR4-Au-Fe2O3 NPs have reasonable biocompatibility and integration of T2-weighted MRI contrast and tumor-targeting functionalities. The anti- CXCR4-Au-Fe2O3 NPs exhibit strong interactions with two kinds of breast tumor cells, MCF-7 cells and MDA-MB-231 cells, and high negative contrast in MRI of MDA-MB-231 tumor bearing mouse with 62% decreasing of MRI signal, indicating that the anti-CXCR4-Au-Fe2O3 NPs can recognize tumor with high efficacy and specificity.
文摘Over the past few decades,complementary and alternative treatments have become increasingly popular worldwide.The purported therapeutic characteristics of natural products have come under increased scrutiny both in vitro and in vivo as part of efforts to legitimize their usage.One such product is tea tree oil(TTO),a volatile essential oil primarily obtained from the native Australian plant,Melaleuca alternifolia,which has diverse traditional and industrial applications such as topical preparations for the treatment of skin infections.Its anti-inflammatory-linked immunomodulatory actions have also been reported.This systematic review focuses on the anti-inflammatory effects of TTO and its main components that have shown strong immunomodulatory potential.An extensive literature search was performed electronically for data curation on worldwide accepted scientific databases,such as Web of Science,Google Scholar,PubMed,ScienceDirect,Scopus,and esteemed publishers such as Elsevier,Springer,Frontiers,and Taylor&Francis.Considering that the majority of pharmacological studies were conducted on crude oils only,the extracted data were critically analyzed to gain further insight into the prospects of TTO being used as a neuroprotective agent by drug formulation or dietary supplement.In addition,the active constituents contributing to the activity of TTO have not been well justified,and the core mechanisms need to be unveiled especially for anti-inflammatory and immunomodulatory effects leading to neuroprotection.Therefore,this review attempts to correlate the anti-inflammatory and immunomodulatory activity of TTO with its neuroprotective mechanisms.
文摘以氨基-1,2,4-三唑和2-偕二硝甲基-5-硝基四唑(HDNMNT)为原料,通过中和反应合成出两种新型含能离子盐——2-偕二硝甲基-5-硝基四唑3-氨基-1,2,4-三唑盐(3-ATDNMNT)和2-偕二硝甲基-5-硝基四唑4-氨基-1,2,4-三唑盐(4-ATDNMNT),收率分别为95.4%和96.7%;利用FT-IR、1 H NMR、13C NMR、15 N NMR及元素分析等方法对其结构进行表征;采用量子化学方法计算了3-ATDNMNT和4-ATDNMNT的爆轰性能;在标准状态下(膨胀比为70∶1),利用最小自由能原理,分别计算了两种离子盐在丁羟复合推进剂中的能量性能。结果表明,3-ATDNMNT的爆速和爆压分别为8.587km/s和33.58GPa,4-ATDNMNT的爆速和爆压分别为8.693km/s和34.31GPa。以3-ATDNMNT部分取代丁羟复合推进剂中的AP后,丁羟复合推进剂的理论比冲可达2 635.7N·s/kg。以4-ATDNMNT部分取代丁羟复合推进剂中的AP后,当HTPB、Al、AP及4-ATDNMNT各组分质量分数分别为10%、5%、15%及70%时,获得该丁羟复合推进剂的最高理论比冲为2 677.2N·s/kg。
