BACKGROUND Epilepsy is a complex neurological disorder characterized by recurrent,unprovoked seizures resulting from the sudden abnormal discharge of brain neurons.It leads to transient brain dysfunction,manifested by...BACKGROUND Epilepsy is a complex neurological disorder characterized by recurrent,unprovoked seizures resulting from the sudden abnormal discharge of brain neurons.It leads to transient brain dysfunction,manifested by abnormal physical movements and consciousness.It can occur at any age,affecting approximately 65 million worldwide,one third of which are still estimated to suffer from refractory seizures.There is an urgent need for further establishment of seizure models in animals,which provides an approach to model epilepsy and could be used to identify novel anti-epileptic therapeutics in the future.AIM To compare three administration modes for establishing a seizure model caused by N-Methyl-D-aspartic acid(NMDA)in zebrafish.METHODS Three administration routes of NMDA,including immersion,intravitreal injection and intraperitoneal injection,were compared with regard to their effects on inducing seizure-like behaviors in adult zebrafish.We evaluated neurotoxicity by observing behavioral changes in zebrafish and graded those behaviors with a seizure score.In addition,the protective effects of MK-801(Dizocilpine)and natural active constituent resveratrol against NMDA-induced alterations were studied.RESULTS The three NMDA-administration methods triggered different patterns of the epileptic process in adult zebrafish.Seizure scores were increased after increasing NMDA concentration regardless of the mode of administration.However,the curve of immersion continuously rose to a high plateau(after 50 min),while the curves of intravitreal injection and intraperitoneal injection showed a spike in the early stage(10-20 min)followed by a steady decrease in seizure scores.Furthermore,pretreatment with resveratrol and MK-801 significantly delayed seizure onset time and lowered seizure scores.CONCLUSION By comparing the three methods of administration,intravitreal injection of NMDA was the most suitable for establishing an acute epileptic model in zebrafish.Thus,intraperitoneal injection in zebrafish can be applied to simulate diseases such as epilepsy.In addition,NMDA immersion may be an appropriate method to induce persistent seizures.Moreover,MK-801 and resveratrol showed strong anti-epileptic effects;thus,both of them may be clinically valuable treatments for epilepsy.展开更多
The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between th...The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between the amino group of the guest and the carboxyl group of host 1 plus the coordination between the zinc atom of porphyrinatozinc(Ⅱ) and the carbonyl group of the guest. This is a novel binding mode of the metalloporphyrin to amino acid derivatives.展开更多
氨基酸是含有碱性氨基和酸性羧基的有机化合物,是构成蛋白质的基本单位,其种类,数量和排列直接影响蛋白质的生物功能,对维持机体功能有重要意义。氨基酸分子间振动模式(扭转,氢键和集体振动)大部分处于太赫兹(THz)波段,表现出独特的吸...氨基酸是含有碱性氨基和酸性羧基的有机化合物,是构成蛋白质的基本单位,其种类,数量和排列直接影响蛋白质的生物功能,对维持机体功能有重要意义。氨基酸分子间振动模式(扭转,氢键和集体振动)大部分处于太赫兹(THz)波段,表现出独特的吸收特征,因此,对氨基酸进行THz光谱研究,能够更全面了解生物特性。总结前人实测的亮氨酸与异亮氨酸位于0.2~2.6 THz波段的吸收谱,同时,利用量子化学计算方法解释其形成机理。使用Gaussian09软件对单分子构型模拟计算,模拟方法为半经验法(PM6),从头计算法(HF,MP2)和密度泛函理论(B3LYP,M06-2X)结合6-311+G(d,p)高斯型基组;使用Materials Studio 2019软件对晶胞构型模拟计算,模拟方法为广义梯度近似的PBE,PBEsol,RPBE和WC等四种密度泛函结合平面波基组。结果表明:单分子构型模拟均缺少吸收峰位,不同方法对同一振动模式的峰位计算不同,因此,对分子间相互作用较强的结构,进行单一方法的该构型模拟,很大程度不能正确匹配振动模式,且受原子轨道线性组合方法影响,与输入结构相比,输出结构由COO^(-)和NH_(3)^(+)基团变为COOH和NH_(2),无法体现实际振动模式;晶胞构型模拟对分子内和分子间振动模式描述,吸收峰位与实测值匹配较好,不存在质子转移情况,较好指认实测峰位的振动模式。亮氨酸与异亮氨酸使用PBEsol泛函计算结果最接近实测值,说明模拟计算需充分考虑结构与泛函的匹配性,即对结构交换关联能的描述,也说明同一泛函对异构体的普适性,此外,不能以结构优化后差异作为判断泛函是否适用的标准。晶胞构型计算结果包含分子间振动模式,是单分子构型无法得到的结果,且数据进行半峰全宽拟合,导致两种构型结果在某一实测峰位处的振动模式存在差异。展开更多
The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-g...The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-gradient approximation（GGA）, Perdew–Burke–Ernzerhof（PBE）, PBE for solids（PBEsol）, PBE with Wu–Cohen exchange（WC）, and dispersion-corrected PBE, to investigate the effect of these intermolecular contacts on the absorption spectra of glutamine in the terahertz frequency range. Among these calculations, the solid-state simulated results obtained using the WC method exhibit a good agreement with the measured absorption spectra, and the absorption features are assigned with the help of WC. This indicates that the vibrational modes of glutamine were related to the combination of intramolecular and intermolecular motions, the intramolecular modes were dominated by rocking or torsion involving functional groups; the intermolecular modes mainly result from the translational motions of individual molecules, and the rocking of the hydrogenbonded functional groups.展开更多
A unique metal-organic framework（MOF） [Eu_2（L）_3（phen）_2]_n（1, H_2L = 4,6-dibenzoylisophthalic acid, phen = 1,10-phenanthroline） has been synthesized under hydrothermal conditions and characterized by single-c...A unique metal-organic framework（MOF） [Eu_2（L）_3（phen）_2]_n（1, H_2L = 4,6-dibenzoylisophthalic acid, phen = 1,10-phenanthroline） has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray analysis, elemental analyses, powder X-ray diffraction, TGA measurement as well as IR spectra. The crystal is of triclinic system, space group P1, C_（90）H_（52）Eu_2N_4O_（18）, M_r = 1781.32, a = 9.8697（4）, b = 16.7466（6）, c = 22.2556（10） A, α = 87.113（3）, β = 77.575（5）, γ = 89.458（3）°, V = 3587.8（3） A^3, Z = 2, D_c = 1.649 g/cm^3, F（000） = 1780, μ（MoKα） = 1.813 mm^（-1）, Rint = 0.0181, R = 0.0260 and wR = 0.0592 for 14000 observed reflections with I 〉 2σ（I）. X-ray analysis shows that the title compound exhibits a 2D layer structure linked by L ligands with two coordination modes and two distinguished conformations, and further linked into a 3D supramolecular architecture through C-H···O weak interactions between hydrogen of phen phenyl ring and the carboxylate oxygen atom of adjacent sheets. In addition, the luminescence property of 1 was investigated.展开更多
Objecive: To explore the effect of gibberellic acid(GA_3) and its inhibitor paclobutrazol(PBZ)on chemical composition and their pharmacological effects on Andrographis paniculata(Burm.f.) Wall. ex Nees, and to clarify...Objecive: To explore the effect of gibberellic acid(GA_3) and its inhibitor paclobutrazol(PBZ)on chemical composition and their pharmacological effects on Andrographis paniculata(Burm.f.) Wall. ex Nees, and to clarify action mode of andrographolide.Methods: The chemical composition was extracted by sequential extraction with hexane, dichloromethane, ethyl acetate and methanol, respectively. Andrographolide and its derivatives were evaluated by HPLC. Moreover, the metabolic profiling was analyzed by GC-MS. Inhibitory effect of crude extracts was tested against Staphylococcus aureus using agar well diffusion method. Mode of action was tested against mutant yeast by spotting assay. Andrographolide were tested for their mode of action against eukaryotes. Rsults: Among different solvents, dichloromethane gave the highest yield of crude(3.58% DW), with the highest andrographolide content(8.3 mg/g DW). The effect of plant hormone(10 mg/L GA_3 or PBZ) on phytochemical variations and bioactivity of Andrographis paniculata was demonstrated. It was found that PBZ promoted sesquiterpene compounds about 3.5 times over than GA_3 treatment. But inhibitory effect of extracts against Staphylococcus aureus was highest in GA_3 treated plants; andrographolide and 14-deoxy-11,12-didehydroandrographolide contents were significantly higher than those of water or PBZ. It was found that there were 11 strains involving in ergosterol biosynthesis, V-ATPase activity and homeostasis, and superoxide detoxification process. In this regard, andrographolide might cause the damage on the lipid bilayer of yeast cell and plasma membrane by interfering ergosterol biosynthesis.Conclusions: It is found that GA_3 promotes andrographolide and 14-deoxy-11,12-didehydroandrographolide content while PBZ promotes sesquiterpene content. Andrographolide might cause the damage on the lipid bilayer of yeast cell and plasma membrane by interfering ergosterol biosynthesis. It might also affect mitochondria electron transport chain, leading to the occurrence of ROS, which can further harm cell organelles. However, the library screening is the first step to investigate mode of action of andrographolide.展开更多
基金the National Natural Science Foundation of China,No.81760216,No.81160144 and No.31171044.
文摘BACKGROUND Epilepsy is a complex neurological disorder characterized by recurrent,unprovoked seizures resulting from the sudden abnormal discharge of brain neurons.It leads to transient brain dysfunction,manifested by abnormal physical movements and consciousness.It can occur at any age,affecting approximately 65 million worldwide,one third of which are still estimated to suffer from refractory seizures.There is an urgent need for further establishment of seizure models in animals,which provides an approach to model epilepsy and could be used to identify novel anti-epileptic therapeutics in the future.AIM To compare three administration modes for establishing a seizure model caused by N-Methyl-D-aspartic acid(NMDA)in zebrafish.METHODS Three administration routes of NMDA,including immersion,intravitreal injection and intraperitoneal injection,were compared with regard to their effects on inducing seizure-like behaviors in adult zebrafish.We evaluated neurotoxicity by observing behavioral changes in zebrafish and graded those behaviors with a seizure score.In addition,the protective effects of MK-801(Dizocilpine)and natural active constituent resveratrol against NMDA-induced alterations were studied.RESULTS The three NMDA-administration methods triggered different patterns of the epileptic process in adult zebrafish.Seizure scores were increased after increasing NMDA concentration regardless of the mode of administration.However,the curve of immersion continuously rose to a high plateau(after 50 min),while the curves of intravitreal injection and intraperitoneal injection showed a spike in the early stage(10-20 min)followed by a steady decrease in seizure scores.Furthermore,pretreatment with resveratrol and MK-801 significantly delayed seizure onset time and lowered seizure scores.CONCLUSION By comparing the three methods of administration,intravitreal injection of NMDA was the most suitable for establishing an acute epileptic model in zebrafish.Thus,intraperitoneal injection in zebrafish can be applied to simulate diseases such as epilepsy.In addition,NMDA immersion may be an appropriate method to induce persistent seizures.Moreover,MK-801 and resveratrol showed strong anti-epileptic effects;thus,both of them may be clinically valuable treatments for epilepsy.
文摘The binding mode of the amino acid ethyl esters(guest) by 5 (2 carboxylphenyl) 10,15,20 triphenylporphyrinatozinc(Ⅱ)(host 1) was studied by means of 1H NMR spectra. The binding mode is the hydrogen bonding between the amino group of the guest and the carboxyl group of host 1 plus the coordination between the zinc atom of porphyrinatozinc(Ⅱ) and the carbonyl group of the guest. This is a novel binding mode of the metalloporphyrin to amino acid derivatives.
文摘氨基酸是含有碱性氨基和酸性羧基的有机化合物,是构成蛋白质的基本单位,其种类,数量和排列直接影响蛋白质的生物功能,对维持机体功能有重要意义。氨基酸分子间振动模式(扭转,氢键和集体振动)大部分处于太赫兹(THz)波段,表现出独特的吸收特征,因此,对氨基酸进行THz光谱研究,能够更全面了解生物特性。总结前人实测的亮氨酸与异亮氨酸位于0.2~2.6 THz波段的吸收谱,同时,利用量子化学计算方法解释其形成机理。使用Gaussian09软件对单分子构型模拟计算,模拟方法为半经验法(PM6),从头计算法(HF,MP2)和密度泛函理论(B3LYP,M06-2X)结合6-311+G(d,p)高斯型基组;使用Materials Studio 2019软件对晶胞构型模拟计算,模拟方法为广义梯度近似的PBE,PBEsol,RPBE和WC等四种密度泛函结合平面波基组。结果表明:单分子构型模拟均缺少吸收峰位,不同方法对同一振动模式的峰位计算不同,因此,对分子间相互作用较强的结构,进行单一方法的该构型模拟,很大程度不能正确匹配振动模式,且受原子轨道线性组合方法影响,与输入结构相比,输出结构由COO^(-)和NH_(3)^(+)基团变为COOH和NH_(2),无法体现实际振动模式;晶胞构型模拟对分子内和分子间振动模式描述,吸收峰位与实测值匹配较好,不存在质子转移情况,较好指认实测峰位的振动模式。亮氨酸与异亮氨酸使用PBEsol泛函计算结果最接近实测值,说明模拟计算需充分考虑结构与泛函的匹配性,即对结构交换关联能的描述,也说明同一泛函对异构体的普适性,此外,不能以结构优化后差异作为判断泛函是否适用的标准。晶胞构型计算结果包含分子间振动模式,是单分子构型无法得到的结果,且数据进行半峰全宽拟合,导致两种构型结果在某一实测峰位处的振动模式存在差异。
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61302007 and 60977065)the Fundamental Research Funds for the Central Universities of China(Grant No.FRF-SD-12-016A)the Engineering Research Center of Industrial Spectrum Imaging of Beijing,China
文摘The crystal structure of L-glutamine is stabilized by a three-dimensional network of intermolecular hydrogen bonds.We utilize plane-wave density functional theory lattice-dynamics calculations within the generalized-gradient approximation（GGA）, Perdew–Burke–Ernzerhof（PBE）, PBE for solids（PBEsol）, PBE with Wu–Cohen exchange（WC）, and dispersion-corrected PBE, to investigate the effect of these intermolecular contacts on the absorption spectra of glutamine in the terahertz frequency range. Among these calculations, the solid-state simulated results obtained using the WC method exhibit a good agreement with the measured absorption spectra, and the absorption features are assigned with the help of WC. This indicates that the vibrational modes of glutamine were related to the combination of intramolecular and intermolecular motions, the intramolecular modes were dominated by rocking or torsion involving functional groups; the intermolecular modes mainly result from the translational motions of individual molecules, and the rocking of the hydrogenbonded functional groups.
基金supported by the NNSFC(No.21301170)Xiaonei Foundation of Changchun University of Technology
文摘A unique metal-organic framework（MOF） [Eu_2（L）_3（phen）_2]_n（1, H_2L = 4,6-dibenzoylisophthalic acid, phen = 1,10-phenanthroline） has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray analysis, elemental analyses, powder X-ray diffraction, TGA measurement as well as IR spectra. The crystal is of triclinic system, space group P1, C_（90）H_（52）Eu_2N_4O_（18）, M_r = 1781.32, a = 9.8697（4）, b = 16.7466（6）, c = 22.2556（10） A, α = 87.113（3）, β = 77.575（5）, γ = 89.458（3）°, V = 3587.8（3） A^3, Z = 2, D_c = 1.649 g/cm^3, F（000） = 1780, μ（MoKα） = 1.813 mm^（-1）, Rint = 0.0181, R = 0.0260 and wR = 0.0592 for 14000 observed reflections with I 〉 2σ（I）. X-ray analysis shows that the title compound exhibits a 2D layer structure linked by L ligands with two coordination modes and two distinguished conformations, and further linked into a 3D supramolecular architecture through C-H···O weak interactions between hydrogen of phen phenyl ring and the carboxylate oxygen atom of adjacent sheets. In addition, the luminescence property of 1 was investigated.
基金financially supported by Agricultural Research Development Agency(Public Organization)or"ARDA"(Grant No.CRP6005020350)
文摘Objecive: To explore the effect of gibberellic acid(GA_3) and its inhibitor paclobutrazol(PBZ)on chemical composition and their pharmacological effects on Andrographis paniculata(Burm.f.) Wall. ex Nees, and to clarify action mode of andrographolide.Methods: The chemical composition was extracted by sequential extraction with hexane, dichloromethane, ethyl acetate and methanol, respectively. Andrographolide and its derivatives were evaluated by HPLC. Moreover, the metabolic profiling was analyzed by GC-MS. Inhibitory effect of crude extracts was tested against Staphylococcus aureus using agar well diffusion method. Mode of action was tested against mutant yeast by spotting assay. Andrographolide were tested for their mode of action against eukaryotes. Rsults: Among different solvents, dichloromethane gave the highest yield of crude(3.58% DW), with the highest andrographolide content(8.3 mg/g DW). The effect of plant hormone(10 mg/L GA_3 or PBZ) on phytochemical variations and bioactivity of Andrographis paniculata was demonstrated. It was found that PBZ promoted sesquiterpene compounds about 3.5 times over than GA_3 treatment. But inhibitory effect of extracts against Staphylococcus aureus was highest in GA_3 treated plants; andrographolide and 14-deoxy-11,12-didehydroandrographolide contents were significantly higher than those of water or PBZ. It was found that there were 11 strains involving in ergosterol biosynthesis, V-ATPase activity and homeostasis, and superoxide detoxification process. In this regard, andrographolide might cause the damage on the lipid bilayer of yeast cell and plasma membrane by interfering ergosterol biosynthesis.Conclusions: It is found that GA_3 promotes andrographolide and 14-deoxy-11,12-didehydroandrographolide content while PBZ promotes sesquiterpene content. Andrographolide might cause the damage on the lipid bilayer of yeast cell and plasma membrane by interfering ergosterol biosynthesis. It might also affect mitochondria electron transport chain, leading to the occurrence of ROS, which can further harm cell organelles. However, the library screening is the first step to investigate mode of action of andrographolide.
