The protection influence of 8-hydroxy-7-quinolinecarboxaldehyde derivatives against C-steel corrosion was studied in 2 mol·L^(-1)HCl solutions at 30 °C. Measurements were conducted under various experimental...The protection influence of 8-hydroxy-7-quinolinecarboxaldehyde derivatives against C-steel corrosion was studied in 2 mol·L^(-1)HCl solutions at 30 °C. Measurements were conducted under various experimental conditions using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and electrochemical frequency modulation(EFM) techniques. These studies have shown that 8-hydroxy-7-quinolinecarboxaldehyde derivatives are very good "green", mixed-type inhibitors. Corrosion rates obtained from both EFM and EIS methods are comparable with those recorded using Tafel extrapolation method, confirming validation of corrosion rates measured by the latter. The inhibitive action of these 8-hydroxy-7-quinolinecarboxaldehyde derivatives was discussed in terms of blocking the electrode surface by adsorption of the molecules through the active centers contained in their structures following Langmuir adsorption isotherm. Quantum chemical method was also employed to explore the relationship between the inhibitor molecular properties and its protection efficiency.展开更多
The structures of 2,7＇-（ethylene）-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet...The structures of 2,7＇-（ethylene）-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7＇-（ethylene）-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G（d）. The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory （TD-DFT） by the B3LYP method with the 6-31G（d） basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline.展开更多
The novel linear, circular, hooped, and helical molecules based on oligo[8]thio- phene were theoretically studied for the applications of charge transfer devices. To investigate the influence of topology for oligo[8]t...The novel linear, circular, hooped, and helical molecules based on oligo[8]thio- phene were theoretically studied for the applications of charge transfer devices. To investigate the influence of topology for oligo[8]thiophene derivatives, the geometry structures, frontier molecular orbital （FMO） energies, charge transport properties, and stability property were predicted by density functional theory methods. The calculated results reported herein show that the oligo[8]thiophene derivative with linear structure has smaller energy gap, and fused oligo[8]thiophene derivative with circular structure has the smallest reorganization energy among the designed molecules. We have also studied the stability properties of the designed molecules, and oligo[8]thiophene derivatives are more stable tharJ the fused oligo[8]thiophene derivatives.展开更多
The chlorination of S-alkyl(aryl) 0,0-dialkyl dithiophosphates with phosphorus oxychloride proceeds with isomerization to give S-alkyl S'-alkyl(aryl) dithiophosphorochtoridates, which react further with various nu...The chlorination of S-alkyl(aryl) 0,0-dialkyl dithiophosphates with phosphorus oxychloride proceeds with isomerization to give S-alkyl S'-alkyl(aryl) dithiophosphorochtoridates, which react further with various nucleophiles in the presence of base to give the title compounds展开更多
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（1）,4-...The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（1）,4-（2-tert-butylphenoxy）-N-（2-hydroxyethyl）-1,8-naphthalimide（2）, and 4-[2,4-di（tert-butyl）]phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（3）, are investigated by density functional theory（DFT） and time-dependent density functional theory（TD-DFT） calculations in conjunction with polarizable continuum models（PCMs）. Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311＋G（d,p） method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311＋G（d,p） level. We find that the gap between the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.展开更多
Chronic exposure to coplanar polychlorinated biphenyls（PCBs）,a potent inducer of toxic reactive oxygen species（ROS）,in the environment and food can cause liver diseases.It remains unknown whether caffeic acid deri...Chronic exposure to coplanar polychlorinated biphenyls（PCBs）,a potent inducer of toxic reactive oxygen species（ROS）,in the environment and food can cause liver diseases.It remains unknown whether caffeic acid derivatives（CADs） exerted protective effect on PCB-induced hepatotoxicity.We sought to evaluate the activities of 3CADs on PCB169-induced oxidative stress and DNA damage in the liver.Male ICR mice were administered with1 μmol/mL PCB169 at 5 mL/kg body weight for 2 weeks.The mice were given CADs by gastric gavage for 3weeks.We found that PCB169 decreased the growth rate and reduced the levels of superoxide dismutase（SOD）,glutathione（GSH） and GSH peroxidase（GPx）.It increased the liver weight,malondialdehyde（MDA）and 8-hydroxy-2＇-deoxyguanosine（8-OHdG） levels and CYPlAl activity in the liver tissues and plasma of mice（P〈0.05）.Pretreatment of mice with CADs restored the above parameters to normal levels.There was a synergistic protective effect between CADs in preventing MDA and 8-OHdG formation and inducing CYPlAl and phase II metabolism enzyme（SOD,GPx） activities（P〈0.05）.In conclusion,PCB169 induced hepatotoxicity and pretreatment with CADs had synergistic protective effects on liver damage.展开更多
Pigment epithelium-derived factor （PEDF） is an antiangiogenic factor which is effective in tumour inhibition in a variety of tumours and has not yet been studied in bladder tumour before. In this study the expressio...Pigment epithelium-derived factor （PEDF） is an antiangiogenic factor which is effective in tumour inhibition in a variety of tumours and has not yet been studied in bladder tumour before. In this study the expression of PEDF, interleukin-1α （IL-1α） and -8 （IL-8） in bladder tumours was investigated. Immunohistochemistry was performed on 64 bladder tumour and 23 normal uroepithelium samples. Expression change of the factors was compared with clinicopathological parameters. Correlations between PEDF, IL-1α and IL-8 were analyzed. None of the factors was in relation to gender, tumour occurrence, and size or onset pattern. PEDF （P=0.014） and IL-1α （P=0.049） expression was down-regulated with grade progression. PEDF expression was lower in normal uroepithelium than in papillary urothelial neoplasm of low malignant potential （PUNLMP） （P=0.000） and carcinoma （P=0.009） whilst IL-1α （P=0.000 and P=0.000 respectively） and IL-8 （P=0.000 and P=0.023 respectively） expression was higher in the same grouping. PEDF expression had a negative correlation with IL-8 in PUNLMP （P=0.049, r=-0.578） as well as in tumour grouping （P=0.033, r=-0.276）. Deranged expressional change of PEDF, IL-1α and IL-8 could be in relation to loss of differentiation from normal uroepithelium to papillary lesion and eventually to carcinoma.展开更多
The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes...The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes, ?chymotrypsin, papain and thermolysin in reasonable yields. The key steps in this synthesis were the coupling of Phac-Met-OCam and H-Asp(OMe)2 to form Met-Asp peptide bond catalyzed by ?chymotrypsin and the selective hydrolysis of -ester of Phac-Met-Asp(OMe)2 catalyzed by papain.展开更多
The synthesis and crystal structure of a novel calix[8]arene ester are reported herein. The calix[8]arene ester derivative has been characterized by IR, NMR and X-ray crystal analysis. The X-ray structure analysis r...The synthesis and crystal structure of a novel calix[8]arene ester are reported herein. The calix[8]arene ester derivative has been characterized by IR, NMR and X-ray crystal analysis. The X-ray structure analysis revealed that the 8 phenolic hydroxy groups of the calix[8]arene have been substituted by 4 diethyl dibromomalonate molecules with each two adjacent hydroxy oxygen atoms attached to a bridge diethyl malonate.展开更多
A series of star-shaped molecules with benzene core and naphthalimides derivatives end groups have been designed to explore their optical,electronic,and charge transport properties as charge transport and/or luminesce...A series of star-shaped molecules with benzene core and naphthalimides derivatives end groups have been designed to explore their optical,electronic,and charge transport properties as charge transport and/or luminescent materials for organic light-emitting diodes（OLEDs）. The frontier molecular orbitals（FMOs） analysis has turned out that the vertical electronic transitions of absorption and emission are characterized as intramolecular charge transfer（ICT）. The calculated results show that the optical and electronic properties of star-shaped molecules are affected by the substituent groups in N-position of 1,8-naphthalimide ring. Our results suggest that star-shaped molecules with n-butyl（1）,benzene（2）,thiophene（3）,thiophene S？,S？-dioxide（4）,benzo[c][1,2,5]thiadiazole（5）,and 2,7a-dihydrobenzo[d]thiazole（6） fragments are expected to be promising candidates for luminescent and electron transport materials for OLEDs. This study should be helpful in further theoretical investigations on such kind of systems and also to the experimental study for charge transport and/or luminescent materials for OLEDs.展开更多
BACKGROUND： Studies of several animal models of central nervous system diseases have shown that neural progenitor cells （NPCs） can migrate to injured tissues. Stromal cell-derived factor 1 alpha （SDF-la）, and its...BACKGROUND： Studies of several animal models of central nervous system diseases have shown that neural progenitor cells （NPCs） can migrate to injured tissues. Stromal cell-derived factor 1 alpha （SDF-la）, and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE： To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α （TNF-α） and interleukin-8 （IL-8） in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING： An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS： SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R＆D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS： NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES： The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS： Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs （P 〈 0.01）, and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect （P 〈 0.05）. Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α（P 〈 0.01）. CONCLUSION： These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.展开更多
文摘The protection influence of 8-hydroxy-7-quinolinecarboxaldehyde derivatives against C-steel corrosion was studied in 2 mol·L^(-1)HCl solutions at 30 °C. Measurements were conducted under various experimental conditions using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and electrochemical frequency modulation(EFM) techniques. These studies have shown that 8-hydroxy-7-quinolinecarboxaldehyde derivatives are very good "green", mixed-type inhibitors. Corrosion rates obtained from both EFM and EIS methods are comparable with those recorded using Tafel extrapolation method, confirming validation of corrosion rates measured by the latter. The inhibitive action of these 8-hydroxy-7-quinolinecarboxaldehyde derivatives was discussed in terms of blocking the electrode surface by adsorption of the molecules through the active centers contained in their structures following Langmuir adsorption isotherm. Quantum chemical method was also employed to explore the relationship between the inhibitor molecular properties and its protection efficiency.
基金Supported by the Foundation of Education Committee of Gansu Province (No. 0708-11)foundation of Tianshui Normal University (No. TSA0604)
文摘The structures of 2,7＇-（ethylene）-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7＇-（ethylene）-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G（d）. The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory （TD-DFT） by the B3LYP method with the 6-31G（d） basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline.
基金Supported by the National Natural Science Foundation of China(No.21302062)the Science Foundation for Young Teachers of Jilin Agricultural University(No.201219)
文摘The novel linear, circular, hooped, and helical molecules based on oligo[8]thio- phene were theoretically studied for the applications of charge transfer devices. To investigate the influence of topology for oligo[8]thiophene derivatives, the geometry structures, frontier molecular orbital （FMO） energies, charge transport properties, and stability property were predicted by density functional theory methods. The calculated results reported herein show that the oligo[8]thiophene derivative with linear structure has smaller energy gap, and fused oligo[8]thiophene derivative with circular structure has the smallest reorganization energy among the designed molecules. We have also studied the stability properties of the designed molecules, and oligo[8]thiophene derivatives are more stable tharJ the fused oligo[8]thiophene derivatives.
基金This project was supported by National Natrural Science Foundation of China.
文摘The chlorination of S-alkyl(aryl) 0,0-dialkyl dithiophosphates with phosphorus oxychloride proceeds with isomerization to give S-alkyl S'-alkyl(aryl) dithiophosphorochtoridates, which react further with various nucleophiles in the presence of base to give the title compounds
基金supported by the Scientific Research Fund of Hubei Provincial Education Department(No.Q20122909)the Open Fund of Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province(No.PKLHB1314)the First-class Discipline of Forestry in Hubei Minzu University
文摘The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（1）,4-（2-tert-butylphenoxy）-N-（2-hydroxyethyl）-1,8-naphthalimide（2）, and 4-[2,4-di（tert-butyl）]phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（3）, are investigated by density functional theory（DFT） and time-dependent density functional theory（TD-DFT） calculations in conjunction with polarizable continuum models（PCMs）. Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311＋G（d,p） method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311＋G（d,p） level. We find that the gap between the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.
基金supported by the National Natural Science Foundation of China(No:81072338)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (2010)
文摘Chronic exposure to coplanar polychlorinated biphenyls（PCBs）,a potent inducer of toxic reactive oxygen species（ROS）,in the environment and food can cause liver diseases.It remains unknown whether caffeic acid derivatives（CADs） exerted protective effect on PCB-induced hepatotoxicity.We sought to evaluate the activities of 3CADs on PCB169-induced oxidative stress and DNA damage in the liver.Male ICR mice were administered with1 μmol/mL PCB169 at 5 mL/kg body weight for 2 weeks.The mice were given CADs by gastric gavage for 3weeks.We found that PCB169 decreased the growth rate and reduced the levels of superoxide dismutase（SOD）,glutathione（GSH） and GSH peroxidase（GPx）.It increased the liver weight,malondialdehyde（MDA）and 8-hydroxy-2＇-deoxyguanosine（8-OHdG） levels and CYPlAl activity in the liver tissues and plasma of mice（P〈0.05）.Pretreatment of mice with CADs restored the above parameters to normal levels.There was a synergistic protective effect between CADs in preventing MDA and 8-OHdG formation and inducing CYPlAl and phase II metabolism enzyme（SOD,GPx） activities（P〈0.05）.In conclusion,PCB169 induced hepatotoxicity and pretreatment with CADs had synergistic protective effects on liver damage.
基金sponsored in part by Science and Technology Commission of Shanghai Municipality, China (No. 07ZR14018)
文摘Pigment epithelium-derived factor （PEDF） is an antiangiogenic factor which is effective in tumour inhibition in a variety of tumours and has not yet been studied in bladder tumour before. In this study the expression of PEDF, interleukin-1α （IL-1α） and -8 （IL-8） in bladder tumours was investigated. Immunohistochemistry was performed on 64 bladder tumour and 23 normal uroepithelium samples. Expression change of the factors was compared with clinicopathological parameters. Correlations between PEDF, IL-1α and IL-8 were analyzed. None of the factors was in relation to gender, tumour occurrence, and size or onset pattern. PEDF （P=0.014） and IL-1α （P=0.049） expression was down-regulated with grade progression. PEDF expression was lower in normal uroepithelium than in papillary urothelial neoplasm of low malignant potential （PUNLMP） （P=0.000） and carcinoma （P=0.009） whilst IL-1α （P=0.000 and P=0.000 respectively） and IL-8 （P=0.000 and P=0.023 respectively） expression was higher in the same grouping. PEDF expression had a negative correlation with IL-8 in PUNLMP （P=0.049, r=-0.578） as well as in tumour grouping （P=0.033, r=-0.276）. Deranged expressional change of PEDF, IL-1α and IL-8 could be in relation to loss of differentiation from normal uroepithelium to papillary lesion and eventually to carcinoma.
文摘The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes, ?chymotrypsin, papain and thermolysin in reasonable yields. The key steps in this synthesis were the coupling of Phac-Met-OCam and H-Asp(OMe)2 to form Met-Asp peptide bond catalyzed by ?chymotrypsin and the selective hydrolysis of -ester of Phac-Met-Asp(OMe)2 catalyzed by papain.
基金We are grateful to the Nationa]Natural Science Foundation of China for the support of this work(grant No.29771005)
文摘The synthesis and crystal structure of a novel calix[8]arene ester are reported herein. The calix[8]arene ester derivative has been characterized by IR, NMR and X-ray crystal analysis. The X-ray structure analysis revealed that the 8 phenolic hydroxy groups of the calix[8]arene have been substituted by 4 diethyl dibromomalonate molecules with each two adjacent hydroxy oxygen atoms attached to a bridge diethyl malonate.
基金Support by the National Natural Science Foundation of China(No.21563002)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2015MS0201)the Research Program of Sciences at Universities of Inner Mongolia Autonomous Region(No.NJZZ235)
文摘A series of star-shaped molecules with benzene core and naphthalimides derivatives end groups have been designed to explore their optical,electronic,and charge transport properties as charge transport and/or luminescent materials for organic light-emitting diodes（OLEDs）. The frontier molecular orbitals（FMOs） analysis has turned out that the vertical electronic transitions of absorption and emission are characterized as intramolecular charge transfer（ICT）. The calculated results show that the optical and electronic properties of star-shaped molecules are affected by the substituent groups in N-position of 1,8-naphthalimide ring. Our results suggest that star-shaped molecules with n-butyl（1）,benzene（2）,thiophene（3）,thiophene S？,S？-dioxide（4）,benzo[c][1,2,5]thiadiazole（5）,and 2,7a-dihydrobenzo[d]thiazole（6） fragments are expected to be promising candidates for luminescent and electron transport materials for OLEDs. This study should be helpful in further theoretical investigations on such kind of systems and also to the experimental study for charge transport and/or luminescent materials for OLEDs.
基金the National Natural Science Foundation of China,No.30671041the National Basic Research Program of China(973 Program),No. 2005CB623902
文摘BACKGROUND： Studies of several animal models of central nervous system diseases have shown that neural progenitor cells （NPCs） can migrate to injured tissues. Stromal cell-derived factor 1 alpha （SDF-la）, and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE： To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α （TNF-α） and interleukin-8 （IL-8） in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING： An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS： SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R＆D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS： NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES： The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS： Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs （P 〈 0.01）, and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect （P 〈 0.05）. Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α（P 〈 0.01）. CONCLUSION： These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.
