We examined a total of 16 children with epileptic encephalopathy using fluorine-18-fluoro-2-deoxy-D-glucose （18F-FDG） positron emission computed tomography （PET）, magnetic resonance imaging （MRI） and electroence...We examined a total of 16 children with epileptic encephalopathy using fluorine-18-fluoro-2-deoxy-D-glucose （18F-FDG） positron emission computed tomography （PET）, magnetic resonance imaging （MRI） and electroencephalography. Children with infantile spasms showed significant mental retardation, severely abnormal electroencephalogram recordings, and bilateral diffuse cerebral cortex hypometabolism with I^F-FDG PET imaging. MRI in these cases showed brain atrophy, multi-micropolygyria, macrogyria, and porencephalia. In cases with Lennox-Gastaut syndrome, 18F-FDG PET showed bilateral diffuse glucose hypometabolism, while MRI showed cortical atrophy, heterotopic gray matter and tuberous sclerosis. MRI in cases with myoclonic encephalopathy demonstrated bilateral frontal and temporal cortical and white matter atrophy and 18F-FDG PET imaging showed bilateral frontal lobe atrophy with reduced bilateral frontal cortex, occipital cortex, temporal cortex and cerebellar glucose uptake. In children who could not be clearly classified, MRI demonstrated cerebral cortical atrophy and ~aF-FDG PET exhibited multifocal glucose hypometabolism. Overall, this study demonstrated that the degree of brain metabolic abnormality was consistent with clinical seizure severity. In addition, ~SF-FDG PET imaging after treatment was consistent with clinical outcomes. These findings indicate that ~SF-FDG PET can be used to assess the severity of brain injury and prognosis in children with epileptic encephalopathy.展开更多
In this study, we developed a simple and sensitive HPLC method for the determination of lisinopril in human plasma. The sample clean-up was carried out by solid-phase extraction(SPE) using a cation-exchange(Strata-SCX...In this study, we developed a simple and sensitive HPLC method for the determination of lisinopril in human plasma. The sample clean-up was carried out by solid-phase extraction(SPE) using a cation-exchange(Strata-SCX~?) extraction cartridge. After a pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole, the reaction mixture was analyzed on an Agilent Zorbax SB~?-C_(18)(150 mm×4.6 mm, 5 μm). The flow rate was set at 1.0 mL/min. Fluorescence detection was performed at an excitation wavelength of 470 nm and an emission wavelength of 530 nm. The mobile phase consisted of a mixture of methanol and 0.02 M sodium dihydrogen phosphate(pH = 3.0, 60:40, v/v). The average extraction recovery of lisinopril and fluvoxamine(internal standard) was >85%. The method exhibited a linear calibration curve over the concentration range of 1–1000 ng/mL with a correlation coefficient(r^2) of ≥0.98 and a limit of quantification(LOQ) equal to 2 ng/mL. The within-run and between-run precisions were satisfactory with an RSD of 3.8%–13.7%(accuracy: from 95.0% to 96.4%) and 4.273%–14.3%(accuracy: from 94.4% to 98.5%), respectively.展开更多
Er3＋-Yb3＋ codoped oxy-fluoro-tungstosilicate glasses with infrared-to-visible frequency upconversion luminescence were prepared by melting quenching in air.The effects of Er3＋ doping on the optical properties of th...Er3＋-Yb3＋ codoped oxy-fluoro-tungstosilicate glasses with infrared-to-visible frequency upconversion luminescence were prepared by melting quenching in air.The effects of Er3＋ doping on the optical properties of the samples were measured by means of techniques such as optical absorption spectra and photoluminescence spectra.The results showed that intense green and red signals centered at 546 and 665 nm,corresponding to the 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3＋ by a multiphoton stepwise phonon-assisted excited-state absorption process,respectively,were simultaneously observed by exciting the samples with a diode laser operating at 980 nm at room temperature.The upconversion process was found very sensitive to Er3＋ content at a constant Yb2O3 content of 5 mol.%.With the increase of Er3＋ content from 0.5% to 1.5%,the upconversion intensity increased gradually.Further increasing of Er3＋ content to 3.0% resulted in a significant fluorescence quenching.Moreover,the possible upconversion mechanisms were discussed based on the energy-matching conditions and the quadratic dependence on excitation power.展开更多
A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sat...A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.展开更多
The purpose of this paper is to investigate the hydrophobic and mechanical behavior of the fluoro-carbon film on the composite.Fluoro-carbon films were fabricated on C/C and C/SiC composite by microwave ECR chemical v...The purpose of this paper is to investigate the hydrophobic and mechanical behavior of the fluoro-carbon film on the composite.Fluoro-carbon films were fabricated on C/C and C/SiC composite by microwave ECR chemical vapor deposition combined with plasma source ion implantation technology (PSII).The films were investigated in terms of the surface morphology,chemical composition,hydrophobic behavior and mechanical properties.The hydrophobic property was determined by means of contact angle measurements,chemical bond structure was analyzed by fourier-transform infrared spectrum,and critical loading were measured by micro-scratch.The results showed that the fluorine presented mainly in the forms of CF2 group and C=CFx (x=1,2) in the film,the addition of fluorine to the carbon film had a critical influence on the hydrophobicity.Atomic force microscopy (AFM) were used for investigating the effect of surface morphology and roughness on hydrophobicity,it showed that fluoro-carbon films with appropriate surface morphology and roughness could achieve excellent hydrophobicity.展开更多
The title compound VII, 2-fluoro-4-methyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic acid methyl ester （C21H30FNO3, Mr = 363.46）, was prepared through a seven-step reaction from pregnenolone, and characterized by...The title compound VII, 2-fluoro-4-methyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic acid methyl ester （C21H30FNO3, Mr = 363.46）, was prepared through a seven-step reaction from pregnenolone, and characterized by elemental and single-crystal X-ray diffraction analyses as well as IR, MS and 1H-NMR spectra. It is of monoclinic system, space group P21/c with a = 6.3882（7）, b = 9.9033（11）, c = 15.4925（17） , β = 91.923（2）°, V = 979.57（19） 3, Z = 2, Dc = 1.232 mg/m3, μ = 0.088 mm-1, F（000）= 392, R = 0.0465, wR = 0.0989 and λ（MoKα） = 0.71073 . The structure indicates that the four cycles （A： C（1）–C（2）–C（3）–N（1）–C（5）–C（10）, B： C（5）–C（6）–C（7）– C（8）–C（9）–C（10）, C： C（8）–C（14）–C（13）–C（12）–C（11）–C（9）, D： C（14）–C（15）–C（16）–C（17）–C（13）） are in chairand trans-configurations. The results of crystal structure determination show that there exist weak intra-molecular hydrogen bonds, resulting in a two-dimensional supramolecular frame-work of the title compound.展开更多
A novel interpenetrating structure [（HMA^＋）（FB^- ）] ·2H2O of melamine（MA） with 4-fluoro-benzoic acid （HFB） was synthesized. It crystallized in the monoclinic system with space group P21/c. The complex ha...A novel interpenetrating structure [（HMA^＋）（FB^- ）] ·2H2O of melamine（MA） with 4-fluoro-benzoic acid （HFB） was synthesized. It crystallized in the monoclinic system with space group P21/c. The complex has a interpenetrating 2D structure with hydrogen-bonded grid networks. Carboxylic acid to melamine proton transfer occurs in the complex. The adjacent HMA^＋ cations related by an inverse center form cationic [HMA^＋]∞ ribbons via a pair of N-H…N hydrogen bonds. Adjacent FB-anions are paired by C-H…F hydrogen bonds to form dimers, which are connected to [HMA^＋]∞ ribbons through N-H…O interactions. The supramolecular features in the complex are guided by control of strong N-H…N, N-H…O and O-H…O hydrogen bonds, as well as highly directional weak C-H…F interactions and aromatic π-π stacking interactions.展开更多
Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical （C5-T2） and lumbar （L3-6） segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-rub...Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical （C5-T2） and lumbar （L3-6） segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-ruby labeling was clearly delineated from the surrounding structure. The labeling traversed the cervical, thoracic and lumbar segments, and was located on the ventral portion of the posterior funiculus on the injected side, proximal to the intermediate zone of the dorsal gray matter. The fluorescence area narrowed rostro-caudally. The spinal cord, spinal cord gray matter and corticospinal tract were reconstructed using 3D-DOCTOR 4.0 software, resulting in a robust three-dimensional profile. Using functionality provided by the reconstruction software, free multi-angle observation and sectioning could be conducted on the spinal cord and corticospinal tract. Our experimental findings indicate that the Fluoro-ruby retrograde fluorescent tracing technique can accurately display the anatomical location of corticospinal tract in the guinea pig and that three-dimensional reconstruction software can be used to provide a three-dimensional image of the corticospinal tract.展开更多
A novel and simple procedure for synthesis of azanucleoside by Mitsunobu reaction between N-（p-nitrobenzyloxycarbonyl）- trans-4-hydroxy-D-proline methyl ester obtained from trans-4-hydroxy-L-proline after six-step r...A novel and simple procedure for synthesis of azanucleoside by Mitsunobu reaction between N-（p-nitrobenzyloxycarbonyl）- trans-4-hydroxy-D-proline methyl ester obtained from trans-4-hydroxy-L-proline after six-step reaction and 2-fluoro-6-azidopurine is described, and azanucleoside is fluorinated by new fluridizer 2,2-difluoro-1,3-dimethylimidazolidine （DFI）. All reactions could be carried out under mild condition.展开更多
Two Schiff base complexes [Cu（L）2] （1） and [Zn（L）2]·3H2O（2） of （E）-4-fluoro-2-（（3-morpholino propylimino）methyl）phenol （HL） have been synthesized and characterized by elemental analysis and single...Two Schiff base complexes [Cu（L）2] （1） and [Zn（L）2]·3H2O（2） of （E）-4-fluoro-2-（（3-morpholino propylimino）methyl）phenol （HL） have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Crystal data for 1： triclinic, space group Pī with a=4.8000（10）, b=11.109（2）, c=13.921（3）,α=66.55（3）,β=80.35（3）,γ=81.09（3）°, V=668.2（2）3 , Z=1, Dc=1.477g/cm 3 , F（000）=311, and the final R=0.0744 and wR=0.1601 for 2301 observed reflections with I 〉 2σ（I）. And those for 2： monoclinic, space group P21 /c with a=14.789（3）, b=11.713（2）, c=18.846（4）,β=107.85（3）°, V=3107.4（11）3 , Z=4, D c=1.389 g/cm 3 , F（000）=1368, and the final R=0.0749 and wR=0.1348 for 5423 observed reflections with I 〉 2σ（I）. Both 1 and 2 are four-coordinated complexes, with a square-planar geometry of copper（Ⅱ） in 1 and a slightly distorted tetrahedral geometry of zinc（Ⅱ） in 2. An asymmetric unit consists of only one half of a Cu ion and one L ligand in 1, while an asymmetric unit is composed of one Zn ion, two L ligands and three water molecules in 2. Non-classical C-H···O and C-H F hydrogen bonds play important roles in the formation of a 1D chain of 1, but O-H O and O-H N hydrogen bonds play dominant roles in the self-assembly of a 3D network of 2. The antibacterial activities of 1 and 2 against B. subtilis, S. aureus, S. faecalis, P. aeruginosa, E. coli and E. cloacae have been evaluated by MTT method.展开更多
Lithium aluminium amide [LiAI（NHR）4] 5 obtained by treating the primary amine 4 with LiAlH4 could promote the ring opening of epoxide 2 and led to high regioselective product of racemic bis[2-（6-fluoro-2-chromanyl...Lithium aluminium amide [LiAI（NHR）4] 5 obtained by treating the primary amine 4 with LiAlH4 could promote the ring opening of epoxide 2 and led to high regioselective product of racemic bis[2-（6-fluoro-2-chromanyl）-2-hydroxyethyl]amine methanesulfonic acid salt 7.展开更多
基金the National Natural Science Foundation of China, No. 81071046the Guangdong Provincial Science and Technology Program, No. 2009B030801250+1 种基金2010 Guangdong Provincial Science and Technology Program, No. 2010B031600159the Guangdong Province Natural Science Foundation, No. 7001205
文摘We examined a total of 16 children with epileptic encephalopathy using fluorine-18-fluoro-2-deoxy-D-glucose （18F-FDG） positron emission computed tomography （PET）, magnetic resonance imaging （MRI） and electroencephalography. Children with infantile spasms showed significant mental retardation, severely abnormal electroencephalogram recordings, and bilateral diffuse cerebral cortex hypometabolism with I^F-FDG PET imaging. MRI in these cases showed brain atrophy, multi-micropolygyria, macrogyria, and porencephalia. In cases with Lennox-Gastaut syndrome, 18F-FDG PET showed bilateral diffuse glucose hypometabolism, while MRI showed cortical atrophy, heterotopic gray matter and tuberous sclerosis. MRI in cases with myoclonic encephalopathy demonstrated bilateral frontal and temporal cortical and white matter atrophy and 18F-FDG PET imaging showed bilateral frontal lobe atrophy with reduced bilateral frontal cortex, occipital cortex, temporal cortex and cerebellar glucose uptake. In children who could not be clearly classified, MRI demonstrated cerebral cortical atrophy and ~aF-FDG PET exhibited multifocal glucose hypometabolism. Overall, this study demonstrated that the degree of brain metabolic abnormality was consistent with clinical seizure severity. In addition, ~SF-FDG PET imaging after treatment was consistent with clinical outcomes. These findings indicate that ~SF-FDG PET can be used to assess the severity of brain injury and prognosis in children with epileptic encephalopathy.
基金The part of a Pham D thesis supported by Tehran University of Medical Sciences(Grant No.23049-92-02-92)
文摘In this study, we developed a simple and sensitive HPLC method for the determination of lisinopril in human plasma. The sample clean-up was carried out by solid-phase extraction(SPE) using a cation-exchange(Strata-SCX~?) extraction cartridge. After a pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole, the reaction mixture was analyzed on an Agilent Zorbax SB~?-C_(18)(150 mm×4.6 mm, 5 μm). The flow rate was set at 1.0 mL/min. Fluorescence detection was performed at an excitation wavelength of 470 nm and an emission wavelength of 530 nm. The mobile phase consisted of a mixture of methanol and 0.02 M sodium dihydrogen phosphate(pH = 3.0, 60:40, v/v). The average extraction recovery of lisinopril and fluvoxamine(internal standard) was >85%. The method exhibited a linear calibration curve over the concentration range of 1–1000 ng/mL with a correlation coefficient(r^2) of ≥0.98 and a limit of quantification(LOQ) equal to 2 ng/mL. The within-run and between-run precisions were satisfactory with an RSD of 3.8%–13.7%(accuracy: from 95.0% to 96.4%) and 4.273%–14.3%(accuracy: from 94.4% to 98.5%), respectively.
基金supported by the Fundamental Research Funds for the Central Universities
文摘Er3＋-Yb3＋ codoped oxy-fluoro-tungstosilicate glasses with infrared-to-visible frequency upconversion luminescence were prepared by melting quenching in air.The effects of Er3＋ doping on the optical properties of the samples were measured by means of techniques such as optical absorption spectra and photoluminescence spectra.The results showed that intense green and red signals centered at 546 and 665 nm,corresponding to the 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3＋ by a multiphoton stepwise phonon-assisted excited-state absorption process,respectively,were simultaneously observed by exciting the samples with a diode laser operating at 980 nm at room temperature.The upconversion process was found very sensitive to Er3＋ content at a constant Yb2O3 content of 5 mol.%.With the increase of Er3＋ content from 0.5% to 1.5%,the upconversion intensity increased gradually.Further increasing of Er3＋ content to 3.0% resulted in a significant fluorescence quenching.Moreover,the possible upconversion mechanisms were discussed based on the energy-matching conditions and the quadratic dependence on excitation power.
基金Tshe prOject!(39770469) supported by the National Natural Science Foundation of China.
文摘A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.
文摘The purpose of this paper is to investigate the hydrophobic and mechanical behavior of the fluoro-carbon film on the composite.Fluoro-carbon films were fabricated on C/C and C/SiC composite by microwave ECR chemical vapor deposition combined with plasma source ion implantation technology (PSII).The films were investigated in terms of the surface morphology,chemical composition,hydrophobic behavior and mechanical properties.The hydrophobic property was determined by means of contact angle measurements,chemical bond structure was analyzed by fourier-transform infrared spectrum,and critical loading were measured by micro-scratch.The results showed that the fluorine presented mainly in the forms of CF2 group and C=CFx (x=1,2) in the film,the addition of fluorine to the carbon film had a critical influence on the hydrophobicity.Atomic force microscopy (AFM) were used for investigating the effect of surface morphology and roughness on hydrophobicity,it showed that fluoro-carbon films with appropriate surface morphology and roughness could achieve excellent hydrophobicity.
基金supported by Young Science Fund of Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang Sci-Tech. University),Ministry of Education
文摘The title compound VII, 2-fluoro-4-methyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic acid methyl ester （C21H30FNO3, Mr = 363.46）, was prepared through a seven-step reaction from pregnenolone, and characterized by elemental and single-crystal X-ray diffraction analyses as well as IR, MS and 1H-NMR spectra. It is of monoclinic system, space group P21/c with a = 6.3882（7）, b = 9.9033（11）, c = 15.4925（17） , β = 91.923（2）°, V = 979.57（19） 3, Z = 2, Dc = 1.232 mg/m3, μ = 0.088 mm-1, F（000）= 392, R = 0.0465, wR = 0.0989 and λ（MoKα） = 0.71073 . The structure indicates that the four cycles （A： C（1）–C（2）–C（3）–N（1）–C（5）–C（10）, B： C（5）–C（6）–C（7）– C（8）–C（9）–C（10）, C： C（8）–C（14）–C（13）–C（12）–C（11）–C（9）, D： C（14）–C（15）–C（16）–C（17）–C（13）） are in chairand trans-configurations. The results of crystal structure determination show that there exist weak intra-molecular hydrogen bonds, resulting in a two-dimensional supramolecular frame-work of the title compound.
基金Supported by the National Natural Science Foundation of China(No.20972178)a Grant for Key Research Items in Na-tural Science of Guangdong Higher Education Institutions of China(No.06Z027)
文摘A novel interpenetrating structure [（HMA^＋）（FB^- ）] ·2H2O of melamine（MA） with 4-fluoro-benzoic acid （HFB） was synthesized. It crystallized in the monoclinic system with space group P21/c. The complex has a interpenetrating 2D structure with hydrogen-bonded grid networks. Carboxylic acid to melamine proton transfer occurs in the complex. The adjacent HMA^＋ cations related by an inverse center form cationic [HMA^＋]∞ ribbons via a pair of N-H…N hydrogen bonds. Adjacent FB-anions are paired by C-H…F hydrogen bonds to form dimers, which are connected to [HMA^＋]∞ ribbons through N-H…O interactions. The supramolecular features in the complex are guided by control of strong N-H…N, N-H…O and O-H…O hydrogen bonds, as well as highly directional weak C-H…F interactions and aromatic π-π stacking interactions.
基金supported by a grant from the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical （C5-T2） and lumbar （L3-6） segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-ruby labeling was clearly delineated from the surrounding structure. The labeling traversed the cervical, thoracic and lumbar segments, and was located on the ventral portion of the posterior funiculus on the injected side, proximal to the intermediate zone of the dorsal gray matter. The fluorescence area narrowed rostro-caudally. The spinal cord, spinal cord gray matter and corticospinal tract were reconstructed using 3D-DOCTOR 4.0 software, resulting in a robust three-dimensional profile. Using functionality provided by the reconstruction software, free multi-angle observation and sectioning could be conducted on the spinal cord and corticospinal tract. Our experimental findings indicate that the Fluoro-ruby retrograde fluorescent tracing technique can accurately display the anatomical location of corticospinal tract in the guinea pig and that three-dimensional reconstruction software can be used to provide a three-dimensional image of the corticospinal tract.
文摘A novel and simple procedure for synthesis of azanucleoside by Mitsunobu reaction between N-（p-nitrobenzyloxycarbonyl）- trans-4-hydroxy-D-proline methyl ester obtained from trans-4-hydroxy-L-proline after six-step reaction and 2-fluoro-6-azidopurine is described, and azanucleoside is fluorinated by new fluridizer 2,2-difluoro-1,3-dimethylimidazolidine （DFI）. All reactions could be carried out under mild condition.
基金supported by the China Postdoctoral Science Foundation (No.20110491380)the Fundamental Research Funds for the Central Universities (No.ZYGX2009J085)
文摘Two Schiff base complexes [Cu（L）2] （1） and [Zn（L）2]·3H2O（2） of （E）-4-fluoro-2-（（3-morpholino propylimino）methyl）phenol （HL） have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Crystal data for 1： triclinic, space group Pī with a=4.8000（10）, b=11.109（2）, c=13.921（3）,α=66.55（3）,β=80.35（3）,γ=81.09（3）°, V=668.2（2）3 , Z=1, Dc=1.477g/cm 3 , F（000）=311, and the final R=0.0744 and wR=0.1601 for 2301 observed reflections with I 〉 2σ（I）. And those for 2： monoclinic, space group P21 /c with a=14.789（3）, b=11.713（2）, c=18.846（4）,β=107.85（3）°, V=3107.4（11）3 , Z=4, D c=1.389 g/cm 3 , F（000）=1368, and the final R=0.0749 and wR=0.1348 for 5423 observed reflections with I 〉 2σ（I）. Both 1 and 2 are four-coordinated complexes, with a square-planar geometry of copper（Ⅱ） in 1 and a slightly distorted tetrahedral geometry of zinc（Ⅱ） in 2. An asymmetric unit consists of only one half of a Cu ion and one L ligand in 1, while an asymmetric unit is composed of one Zn ion, two L ligands and three water molecules in 2. Non-classical C-H···O and C-H F hydrogen bonds play important roles in the formation of a 1D chain of 1, but O-H O and O-H N hydrogen bonds play dominant roles in the self-assembly of a 3D network of 2. The antibacterial activities of 1 and 2 against B. subtilis, S. aureus, S. faecalis, P. aeruginosa, E. coli and E. cloacae have been evaluated by MTT method.
基金the National 863 Program(No.2003AA323030)the National Natural Science Foundation of China(No.50272069 and No.20472090)for financial support.
文摘Lithium aluminium amide [LiAI（NHR）4] 5 obtained by treating the primary amine 4 with LiAlH4 could promote the ring opening of epoxide 2 and led to high regioselective product of racemic bis[2-（6-fluoro-2-chromanyl）-2-hydroxyethyl]amine methanesulfonic acid salt 7.
