AIM: To observe the effect of cholecystokinin (CCK) on lipofusin value, neuronal dendrite and spine ultrastructure, and total cellular protein during the process of experimental neuronal aging. METHODS: Experimental n...AIM: To observe the effect of cholecystokinin (CCK) on lipofusin value, neuronal dendrite and spine ultrastructure, and total cellular protein during the process of experimental neuronal aging. METHODS: Experimental neuronal aging study model was established by NBA2 cellular serum-free culture method. By using single intracellular lipofusin value from microspectrophotometry, morphology of neuronal dendrites and spines from the scanner electron microscopy, and total cellular protein as the indexes of experimental neuronal aging, we observed the effect of CCKs on the process of experimental neuronal aging. RESULTS: Under the condition of serum-free culture, intracellular fluorescence value (%) increased with the extension of culture time (1 d 8.51±3.43; 5 d 10.12±3.03; 10 d 20.54±10.3; 15 d 36.88±10.49; bP<0.01). When CCK was added to serum-free culture medium, intracellular lipofusin value (%) decreased remarkably after consecutive CCK reaction for 10 and 15 d (control 36.88±10.49; 5 d 32.03±10.01; 10 d 14.37±5.55; 15 d 17.31±4.80; bP<0.01). As the time of serum-free culturing was prolonged, the number of neuronal dendrite and spine cells decreased. The later increased in number when CCK8 was added. CCK8 could improve the total cellular protein in the process of experimental neuronal aging. CONCLUSION: CCKs may prolong the process of experimental neuronal aging by maintaining the structure and the number of neuronal dendrite and spine cells and changing the total cellular protein.展开更多
Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal tempera...Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.展开更多
Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of d...Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of different salts(NaCl,KCl as well as NH_4Cl)over the temperature range of 298.15–323.15 K at the regular interval of 5 K.CFH drug has been suggested for the treatment of bacterial infections such as urinary tract infections and acute sinusitis.A clear critical micelle concentration(CMC)was obtained for pure CTAB as well as(CFH+CTAB)mixed systems.The decrease in CMC values of CTAB caused by the addition of CFH reveals the existence of the interaction between the components and therefore it is the indication of micelle formation at lower concentration of CTAB and their CMC values further decrease in attendance of salts.A nonlinear behavior in the CMC versus T plot was observed in all the cases.The ΔG_m^0 values are found to be negative in present study systems demonstrated the stability of the solution.The values of ΔH_m^0 and ΔS_m^0 reveal the existence of hydrophobic and electrostatic interactions between CFH and CTAB.The thermodynamic properties of transfer for the micellization were also evaluated and discussed in detail.Molecular dynamic simulation disclosed that environment of water and salts have impact on the hydrophobic interaction between CFH and CTAB.In water and salts,CTAB adopts spherical micelle in which charged hydrophilic groups are interacted with waters whereas hydrophobic tails form the core of the micelle.This hydrophobic core region is highly conserved and protected.In addition,micelle formation is more favorable in aqueous Na Cl solution than other solutions.展开更多
The photobrominations of 1-methylnaphthalene (1-MN) and 2-methylnaphthalene (2-MN) were investigated by using N-bromosuccinimide (NBS) as brominating agent. The results show that under nitrogen atmosphere, side-chain ...The photobrominations of 1-methylnaphthalene (1-MN) and 2-methylnaphthalene (2-MN) were investigated by using N-bromosuccinimide (NBS) as brominating agent. The results show that under nitrogen atmosphere, side-chain methyl group on 1-MN and 2-MN can be brominated selectlvely with visible light and NBS in benzene at room temperature, and that 1-MN is photobrominated easier than 2-MN.展开更多
A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the ...A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the solvent mixture of 1,1,2-trichloroethane and water, the other is 1,1,2-trichloroethane alone. The effects of solvent, bromine excess added and reaction duration on the bromization reac-tion were studied. The shift of maximum absorbance wave-length both in solution and in solid thin film was investigated comparatively, discovering that both were bathochromism but the former was more. TG data showed that the tem-perature of thermal decomposition decreased continuously with the increase of numbers of bromine. Finally, the frag-ments produced during the bromization of (OAr)4PcPb in 1,1,2- trichloroethane were characterized by GC/MS. Based on the electronic structure, the possible mechanism of de-composition of these compounds was presented and dis-cussed.展开更多
基金Supported by Shanghai Natural Science Foundation, No. 9821314040
文摘AIM: To observe the effect of cholecystokinin (CCK) on lipofusin value, neuronal dendrite and spine ultrastructure, and total cellular protein during the process of experimental neuronal aging. METHODS: Experimental neuronal aging study model was established by NBA2 cellular serum-free culture method. By using single intracellular lipofusin value from microspectrophotometry, morphology of neuronal dendrites and spines from the scanner electron microscopy, and total cellular protein as the indexes of experimental neuronal aging, we observed the effect of CCKs on the process of experimental neuronal aging. RESULTS: Under the condition of serum-free culture, intracellular fluorescence value (%) increased with the extension of culture time (1 d 8.51±3.43; 5 d 10.12±3.03; 10 d 20.54±10.3; 15 d 36.88±10.49; bP<0.01). When CCK was added to serum-free culture medium, intracellular lipofusin value (%) decreased remarkably after consecutive CCK reaction for 10 and 15 d (control 36.88±10.49; 5 d 32.03±10.01; 10 d 14.37±5.55; 15 d 17.31±4.80; bP<0.01). As the time of serum-free culturing was prolonged, the number of neuronal dendrite and spine cells decreased. The later increased in number when CCK8 was added. CCK8 could improve the total cellular protein in the process of experimental neuronal aging. CONCLUSION: CCKs may prolong the process of experimental neuronal aging by maintaining the structure and the number of neuronal dendrite and spine cells and changing the total cellular protein.
基金Project(CHCL0501) supported by Hubei Provincial Open Fund of Key Laboratory of Catalytic Material Science and Technology
文摘Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.
文摘Interaction between beta-lactum antibiotic drug ciprofloxacin hydrochloride(CFH)and cationic surfactant cetyltrimethylammonium bromide(CTAB)was performed conductometrically in aqueous as well as in the occurrence of different salts(NaCl,KCl as well as NH_4Cl)over the temperature range of 298.15–323.15 K at the regular interval of 5 K.CFH drug has been suggested for the treatment of bacterial infections such as urinary tract infections and acute sinusitis.A clear critical micelle concentration(CMC)was obtained for pure CTAB as well as(CFH+CTAB)mixed systems.The decrease in CMC values of CTAB caused by the addition of CFH reveals the existence of the interaction between the components and therefore it is the indication of micelle formation at lower concentration of CTAB and their CMC values further decrease in attendance of salts.A nonlinear behavior in the CMC versus T plot was observed in all the cases.The ΔG_m^0 values are found to be negative in present study systems demonstrated the stability of the solution.The values of ΔH_m^0 and ΔS_m^0 reveal the existence of hydrophobic and electrostatic interactions between CFH and CTAB.The thermodynamic properties of transfer for the micellization were also evaluated and discussed in detail.Molecular dynamic simulation disclosed that environment of water and salts have impact on the hydrophobic interaction between CFH and CTAB.In water and salts,CTAB adopts spherical micelle in which charged hydrophilic groups are interacted with waters whereas hydrophobic tails form the core of the micelle.This hydrophobic core region is highly conserved and protected.In addition,micelle formation is more favorable in aqueous Na Cl solution than other solutions.
文摘The photobrominations of 1-methylnaphthalene (1-MN) and 2-methylnaphthalene (2-MN) were investigated by using N-bromosuccinimide (NBS) as brominating agent. The results show that under nitrogen atmosphere, side-chain methyl group on 1-MN and 2-MN can be brominated selectlvely with visible light and NBS in benzene at room temperature, and that 1-MN is photobrominated easier than 2-MN.
文摘A series of 1,8,15,22-tetra(2,4-ditertbutylphen- oxy) phthalocyanines [a-(oAr)4PcM, M1=(H)2, M2=Pd, M3= Cu, M4=Zn, M5=Pb] were synthesized in this study. Each compound was bromized in two kinds of solvent. One is the solvent mixture of 1,1,2-trichloroethane and water, the other is 1,1,2-trichloroethane alone. The effects of solvent, bromine excess added and reaction duration on the bromization reac-tion were studied. The shift of maximum absorbance wave-length both in solution and in solid thin film was investigated comparatively, discovering that both were bathochromism but the former was more. TG data showed that the tem-perature of thermal decomposition decreased continuously with the increase of numbers of bromine. Finally, the frag-ments produced during the bromization of (OAr)4PcPb in 1,1,2- trichloroethane were characterized by GC/MS. Based on the electronic structure, the possible mechanism of de-composition of these compounds was presented and dis-cussed.
