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Search Results: 1 - 10 of 120000 matches for " Wang XB "
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Research on the regulation of the spatial structure of acetylcholinesterase tetramer with high efficiency by AFM
Jiang S, Wang XB, Xi RG, Zhang YG
International Journal of Nanomedicine , 2013, DOI: http://dx.doi.org/10.2147/IJN.S41591
Abstract: earch on the regulation of the spatial structure of acetylcholinesterase tetramer with high efficiency by AFM Original Research (207) Total Article Views Authors: Jiang S, Wang XB, Xi RG, Zhang YG Published Date March 2013 Volume 2013:8 Pages 1095 - 1102 DOI: http://dx.doi.org/10.2147/IJN.S41591 Received: 14 December 2012 Accepted: 26 January 2013 Published: 14 March 2013 Shuang Jiang,1 Xiaobo Wang,1 Ronggang Xi,1 Yingge Zhang2 1210th Hospital of People Liberation Army, Dalian, People’s Republic of China; 2Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, People’s Republic of China Abstract: Atomic force microscopy (AFM) was applied for obtaining structural information about acetylcholinesterase (AChE) tetramer (AChE G4) before and after reaction with S-acetylcholine iodide (S-ACh), in the presence or absence of propidium iodide (PI), an inhibitor for peripheral anionic sites (PAS). An iced-bath ultrasound was used to prepare the phospholipid membrane. Ves-fusion technique was applied for incorporating AChE G4 in a lipid layer on mica. Before reaction with substrates, the single AChE G4 particle was ellipsoid in shape with a clear border. It had a smooth surface with a central projection. The four subunits of a single enzyme particle were arranged tightly (no separated subunits being found, with an average size of 89 ± 7 nm in length, 68 ± 9 nm in width, and 6 ± 3 nm in height). After reaction with S-ACh in the absence of PI, the loose arrangement of subunits of AChE G4 was seen, with an average size of 104 ± 7 nm in length, 91 ± 5 nm in width, and 8 ± 2 nm in height. Also there was free-flowing space amongst the four subunits of the AChE G4. This was consistent with the results of the X-ray diffraction crystallography and molecular dynamics studies. The apparent free space was the central path of AChE G4, changing from small to big, to small, to lateral door appearance, with an average size of 60 ± 5 nm in length and 51 ± 9 nm in width. The size of lateral door was 52 ± 5 nm in width and 32 ± 3 nm in depth on average. In the presence of PI, S-ACh could not cause topological structure changes of AChE G4. AFM verified that the central path might govern the turnover of the enzyme morphologically, and the interactions between PI and S-ACh might gate the creation of a central path and the opening of ACG in monomer; and the combination of S-ACh with peripheral anionic sites is conducive to the opening of ACG while PI can inhibit this action. Resolution at the inframolecular level is favorable in providing substantial information on how the spatial structure is adapted to the high efficiency of AChE molecules.
Research on the regulation of the spatial structure of acetylcholinesterase tetramer with high efficiency by AFM
Jiang S,Wang XB,Xi RG,Zhang YG
International Journal of Nanomedicine , 2013,
Abstract: Shuang Jiang,1 Xiaobo Wang,1 Ronggang Xi,1 Yingge Zhang2 1210th Hospital of People Liberation Army, Dalian, People’s Republic of China; 2Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, People’s Republic of China Abstract: Atomic force microscopy (AFM) was applied for obtaining structural information about acetylcholinesterase (AChE) tetramer (AChE G4) before and after reaction with S-acetylcholine iodide (S-ACh), in the presence or absence of propidium iodide (PI), an inhibitor for peripheral anionic sites (PAS). An iced-bath ultrasound was used to prepare the phospholipid membrane. Ves-fusion technique was applied for incorporating AChE G4 in a lipid layer on mica. Before reaction with substrates, the single AChE G4 particle was ellipsoid in shape with a clear border. It had a smooth surface with a central projection. The four subunits of a single enzyme particle were arranged tightly (no separated subunits being found, with an average size of 89 ± 7 nm in length, 68 ± 9 nm in width, and 6 ± 3 nm in height). After reaction with S-ACh in the absence of PI, the loose arrangement of subunits of AChE G4 was seen, with an average size of 104 ± 7 nm in length, 91 ± 5 nm in width, and 8 ± 2 nm in height. Also there was free-flowing space amongst the four subunits of the AChE G4. This was consistent with the results of the X-ray diffraction crystallography and molecular dynamics studies. The apparent free space was the central path of AChE G4, changing from small to big, to small, to lateral door appearance, with an average size of 60 ± 5 nm in length and 51 ± 9 nm in width. The size of lateral door was 52 ± 5 nm in width and 32 ± 3 nm in depth on average. In the presence of PI, S-ACh could not cause topological structure changes of AChE G4. AFM verified that the central path might govern the turnover of the enzyme morphologically, and the interactions between PI and S-ACh might gate the creation of a central path and the opening of ACG in monomer; and the combination of S-ACh with peripheral anionic sites is conducive to the opening of ACG while PI can inhibit this action. Resolution at the inframolecular level is favorable in providing substantial information on how the spatial structure is adapted to the high efficiency of AChE molecules. Keywords: AChE, AFM, ACG, Ves-fusion, phospholipid membrane
Targeted inhibition of mammalian target of rapamycin (mTOR) enhances radiosensitivity in pancreatic carcinoma cells
Dai ZJ, Gao J, Kang HF, Ma YG, Ma XB, Lu WF, Lin S, Ma HB, Wang XJ, Wu WY
Drug Design, Development and Therapy , 2013, DOI: http://dx.doi.org/10.2147/DDDT.S42390
Abstract: rgeted inhibition of mammalian target of rapamycin (mTOR) enhances radiosensitivity in pancreatic carcinoma cells Original Research (22) Total Article Views Authors: Dai ZJ, Gao J, Kang HF, Ma YG, Ma XB, Lu WF, Lin S, Ma HB, Wang XJ, Wu WY Published Date March 2013 Volume 2013:7 Pages 149 - 159 DOI: http://dx.doi.org/10.2147/DDDT.S42390 Received: 05 January 2013 Accepted: 06 February 2013 Published: 21 March 2013 Zhi-Jun Dai,1,* Jie Gao,2,* Hua-Feng Kang,1,* Yu-Guang Ma,1 Xiao-Bin Ma,1 Wang-Feng Lu,1 Shuai Lin,1 Hong-Bing Ma,1 Xi-Jing Wang,1 Wen-Ying Wu3 1Department of Oncology, 2Department of Nephrology, 3Department of Pharmacology, Second Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an, People's Republic of China *These authors contributed equally to this work Abstract: The mammalian target of rapamycin (mTOR) is a protein kinase that regulates protein translation, cell growth, and apoptosis. Rapamycin (RPM), a specific inhibitor of mTOR, exhibits potent and broad in vitro and in vivo antitumor activity against leukemia, breast cancer, and melanoma. Recent studies showing that RPM sensitizes cancers to chemotherapy and radiation therapy have attracted considerable attention. This study aimed to examine the radiosensitizing effect of RPM in vitro, as well as its mechanism of action. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and colony formation assay showed that 10 nmol/L to 15 nmol/L of RPM had a radiosensitizing effects on pancreatic carcinoma cells in vitro. Furthermore, a low dose of RPM induced autophagy and reduced the number of S-phase cells. When radiation treatment was combined with RPM, the PC-2 cell cycle arrested in the G2/M phase of the cell cycle. Complementary DNA (cDNA) microarray and reverse transcription polymerase chain reaction (RT-PCR) revealed that the expression of DDB1, RAD51, and XRCC5 were downregulated, whereas the expression of PCNA and ABCC4 were upregulated in PC-2 cells. The results demonstrated that RPM effectively enhanced the radiosensitivity of pancreatic carcinoma cells.
Antitumor activity of folate-targeted, paclitaxel-loaded polymeric micelles on a human esophageal EC9706 cancer cell line
Wu WB, Zheng YH, Wang R, Huang WL, Liu L, Hu XL, Liu S, Yue J, Tong T, Jing XB
International Journal of Nanomedicine , 2012, DOI: http://dx.doi.org/10.2147/IJN.S32620
Abstract: ntitumor activity of folate-targeted, paclitaxel-loaded polymeric micelles on a human esophageal EC9706 cancer cell line Original Research (5131) Total Article Views Authors: Wu WB, Zheng YH, Wang R, Huang WL, Liu L, Hu XL, Liu S, Yue J, Tong T, Jing XB Published Date July 2012 Volume 2012:7 Pages 3487 - 3502 DOI: http://dx.doi.org/10.2147/IJN.S32620 Received: 04 April 2012 Accepted: 31 May 2012 Published: 06 July 2012 Wenbin Wu,1 Yonghui Zheng,2 Rui Wang,2 Weili Huang,3 Lei Liu,2 Xiuli Hu,2 Shi Liu,2 Jun Yue,2 Ti Tong,1 Xiabin Jing2 1Department of Thoracic Surgery, Second Hospital of Jilin University, Changchun, 2State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 3Department of Gastroenterology, the Affiliated Hospital of Beihua University, Jilin, China Background: Esophageal cancer is recognized as one of the most refractory pernicious diseases. In addition, it is an aggressive malignancy with a propensity for local progression and distant dissemination. Because of the poor long-term prognosis for patients with esophageal cancer, increasing attention has focused on the integration of targeted agents into current therapeutics. Nevertheless, there have been few studies reported concerning the therapeutic efficacy of paclitaxel-conjugated polymeric micelles in human esophageal cancer in vivo. Therefore, the aim of this research was to investigate the tumor inhibition effect of composite micelles containing folic acid and paclitaxel on the human esophageal EC9706 cancer cell line. Methods and results: Intravenous administration of folate-targeted, paclitaxel-loaded micelles was demonstrated to be more efficient in inhibiting subcutaneous xenograft tumors and extending the survival rate of tumor-bearing nude mice than free paclitaxel and plain paclitaxel micelles at an equivalent paclitaxel dose of 20 mg/kg, which was further backed up by flow cytometry, TUNEL, and expression of apoptosis-related proteins, including Bax, Bcl2, and caspase 3 in this study. Conclusion: The folate-mediated paclitaxel-loaded polymeric micelle is a promising agent for the treatment of human esophageal cancer.
Analysis of membrane fouling genesis in nanofiltration process for advanced treatment of dyeing and finishing wastewater
染整废水深度处理纳滤工艺膜污染成因分析

Cao Xiao-Bing,Li Tao,Zhou Liu,Yang Hai-Jun,Wang Xiao,
Cao XB
,Li T,Zhou L,Yang HJ,Wang X

环境科学 , 2012,
Abstract: In order to investigate the types and genesis of membrane fouling of nanofiltration desalination system treating dyeing and finishing wastewater of cotton knit textile, comprehensive analysis, using ICP-AES, SEM-EDX, FTIR, TGA, high optical microscope and XRF, was carried out based on tests of influent water quality, and tests of the membrane fouling states of different processes and tests of membrane cleaning. The results showed that the types of membrane fouling included inorganic fouling, organic fouling and microbial fouling. The mass percents of bound water, organic substance and inorganic substance of dry foulants, dried at 105 degrees C, were 8.2%, 41.0% and 50.8% respectively. Ferric salt was the most serious inorganic fouling salt, and the main functional groups, found from organic foulants, were -OH, -CH and -C =C. Several kinds of protozoa were found from the membrane foulants as well as metazoan. The analysis of short-term and long-term membrane fouling indicated that it need a long time cumulative effect for the formation of organic fouling and microbial fouling. The results of NF cleaning tests showed that the mainly reason lead to the decline of membrane flux were organic fouling and microbial fouling, which took 53.3%.
ION HEATING PROCESS DURING PLASMA IMMERSION ION IMPLANTATION
XB Tian,XF Wang,AG Liu,LP Wang,S Y Wang,B Y Tang,P K Chu Advanced Welding Production & Technology National Key Laboratory,Harbin Institute of Technology,Harbin,China,

金属学报(英文版) , 2000,
Abstract: The research on plasma immersion ion implantation has been conducted for a little over ten years. Much is needed to investigate including processing technlogy, plasma sheath dynamics, interaction of plasma and surface, etc. Of the processing methods elavated temperature technique is usually used in PIII to produce a thick modified layer by means of the thermal diffusion. Meanwhile plasma ion heating is more recently developed by Ronghua Wei et al1]. Therefore the temeperature is a critical parameter in plasma ion processing. In this paper we present the theoretical model and analysize the effect of imlantation voltage, plasma density, ion mass,etc on the temperature rise.
Preparation of a nanoscale baohuoside I-phospholipid complex and determination of its absorption: in vivo and in vitro evaluations
Jin X, Zhang ZH, Sun E, Qian Q, Tan XB, Jia XB
International Journal of Nanomedicine , 2012, DOI: http://dx.doi.org/10.2147/IJN.S35965
Abstract: eparation of a nanoscale baohuoside I-phospholipid complex and determination of its absorption: in vivo and in vitro evaluations Original Research (1479) Total Article Views Authors: Jin X, Zhang ZH, Sun E, Qian Q, Tan XB, Jia XB Published Date September 2012 Volume 2012:7 Pages 4907 - 4916 DOI: http://dx.doi.org/10.2147/IJN.S35965 Received: 14 July 2012 Accepted: 17 August 2012 Published: 13 September 2012 Xin Jin,1,2 Zhen-hai Zhang,1 E Sun,1 Qian Qian,1 Xiao-bin Tan,1 Xiao-bin Jia1 1Key Laboratory of New Drug Delivery System of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, 2College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, People's Republic of China Background: Baohuoside I is a potential anticancer drug for a variety of malignancies and has been approved for in vitro use. However, baohuoside I has very poor oral absorption. Methods: In the present study, we prepared baohuoside I-phospholipid complexes of different diameters and determined their physicochemical properties using transmission electron microscopy, ultraviolet spectroscopy, and differential scanning calorimetry. The in vitro absorption of baohuoside I and baohuoside I-phospholipid complexes of different sizes were compared using the Caco-2 cell culture model, and subsequently, the bioavailability of baohuosidel and its complexes were estimated in vivo. Results: Compared with the large-sized phospholipid complexes, a nanoscale phospholipid complex improved the oral bioavailability of baohuoside I. In addition, our results suggest that the smaller the particle size, the faster the complexes crossed the Caco-2 monolayer and the faster they were resorbed after oral administration in rats. The relative oral bioavailability of a nanoscale size 81 ± 10 nm baohuoside I-phospholipid complex (area under the concentration-time curve [AUC] 0–∞)was 342%, while that of baohuoside I and a 227.3 ± 65.2 μm baohuoside I-phospholipid complex was 165%. Conclusion: We enhanced the oral bioavailability of baohuoside I by reducing the particle size of the phospholipid complex to the nanometer range, thereby improving its potential for clinical application.
Enhanced oral absorption of 20(S)-protopanaxadiol by self-assembled liquid crystalline nanoparticles containing piperine: in vitro and in vivo studies
Jin X, Zhang ZH, Sun E, Tan XB, Li SL, Cheng XD, You M, Jia XB
International Journal of Nanomedicine , 2013, DOI: http://dx.doi.org/10.2147/IJN.S38203
Abstract: hanced oral absorption of 20(S)-protopanaxadiol by self-assembled liquid crystalline nanoparticles containing piperine: in vitro and in vivo studies Original Research (506) Total Article Views Authors: Jin X, Zhang ZH, Sun E, Tan XB, Li SL, Cheng XD, You M, Jia XB Published Date February 2013 Volume 2013:8 Pages 641 - 652 DOI: http://dx.doi.org/10.2147/IJN.S38203 Received: 17 September 2012 Accepted: 22 October 2012 Published: 13 February 2013 Xin Jin,1,2 Zhen-hai Zhang,1 E Sun,1 Xiao-bin Tan,1 Song-lin Li,3 Xu-dong Cheng,4 Ming You,4 Xiao-bin Jia1 1Key Laboratory of New Drug Delivery System of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Nanjing, People's Republic of China; 2College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, People's Republic of China; 3Department of Pharmaceutical Analysis and Metabolomics, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing, People's Republic of China; 4ALG Bioscience Co, Ltd, Suzhou, People's Republic of China Background: 20(S)-protopanaxadiol (PPD), similar to several other anticancer agents, has low oral absorption and is extensively metabolized. These factors limit the use of PPD for treatment of human diseases. Methods: In this study, we used cubic nanoparticles containing piperine to improve the oral bioavailability of PPD and to enhance its absorption and inhibit its metabolism. Cubic nanoparticles loaded with PPD and piperine were prepared by fragmentation of glyceryl monoolein (GMO)/poloxamer 407 bulk cubic gel and verified using transmission electron microscopy and differential scanning calorimetry. We evaluated the in vitro release of PPD from these nanoparticles and its absorption across the Caco-2 cell monolayer model, and subsequently, we examined the bioavailability and metabolism of PPD and its nanoparticles in vivo. Results: The in vitro release of PPD from these nanoparticles was less than 5% at 12 hours. PPD-cubosome and PPD-cubosome loaded with piperine (molar ratio PPD/piperine, 1:3) increased the apical to basolateral permeability values of PPD across the Caco-2 cell monolayer from 53% to 64%, respectively. In addition, the results of a pharmacokinetic study in rats showed that the relative bioavailabilities of PPD-cubosome [area under concentration–time curve (AUC)0–∞ ] and PPD-cubosome containing piperine (AUC0–∞) compared to that of raw PPD (AUC0–∞) were 166% and 248%, respectively. Conclusion: The increased bioavailability of PPD-cubosome loaded with piperine is due to an increase in absorption and inhibition of metabolism of PPD by cubic nanoparticles containing piperine rather than because of improved release of PPD. The cubic nanoparticles containing piperine may be a promising oral carrier for anticancer drugs with poor oral absorption and that undergo extensive metabolism by cytochrome P450.
Effects of chitosan and water-soluble chitosan micro- and nanoparticles in obese rats fed a high-fat diet
Zhang HL, Zhong XB, Tao Y, Wu SH, Su ZQ
International Journal of Nanomedicine , 2012, DOI: http://dx.doi.org/10.2147/IJN.S33830
Abstract: ts of chitosan and water-soluble chitosan micro- and nanoparticles in obese rats fed a high-fat diet Original Research (2350) Total Article Views Authors: Zhang HL, Zhong XB, Tao Y, Wu SH, Su ZQ Published Date July 2012 Volume 2012:7 Pages 4069 - 4076 DOI: http://dx.doi.org/10.2147/IJN.S33830 Received: 12 May 2012 Accepted: 15 June 2012 Published: 27 July 2012 Hong-liang Zhang,1,2 Xiao-bin Zhong,1 Yi Tao,3 Si-hui Wu,4 Zheng-quan Su2 1Department of Pharmacy, First Affiliated Hospital of Guangxi Medical University, Nanning, 2Key Research Center of Liver Regulation for Hyperlipemia SATCM/Level 3 Laboratory of Lipid Metabolism, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, 3HEC Pharm Group, Dongguan, 4Department of Pharmacy, Guangdong Food and Drug Vocational Technical School, Guangzhou, China Purpose: This study determined the effects of chitosan (CTS) and water-soluble chitosan (WSC) microparticles (MPs) and nanoparticles (NPs) in rats with high-fat diet-induced obesity. Methods: The rats were randomly separated into eight groups: a normal diet group (the blank control), a high-fat emulsion group (the negative control), CTS and WSC control groups, CTS-MP and WSC-MP groups, and CTS-NP and WSC-NP groups. All groups (except the blank control group) were fed the high-fat diet for 4 weeks to establish the obesity model. Different samples were administered orally once daily to the treatment groups for 4 weeks. Results: A significantly lower weight gain was observed in the WSC-MP and WSC-NP groups, as well as in the CTS-MP and CTS-NP groups, compared with rats given a normal diet and a high-fat diet (P < 0.05). The WSC-MP rats had the least weight gain among all the groups. The food intake in the eight groups had the same trend as weight gain. CTS and WSC MPs and NPs significantly reduced the final amounts of epididymal and perirenal white adipose tissue. Liver weight was reduced in the CTS-MP group compared to rats fed a high-fat diet. Serum total cholesterol and low-density lipoprotein cholesterol were significantly reduced in all treatment groups, with the WSC-MP and CTS-MP groups showing a more significant reduction than the other groups. Triacylglycerol levels were significantly reduced in the WSC-NP group compared to the high-fat group. The mortality rates of CTS-MP, CTS-NP, WSC-MP, and WSC-NP groups were 30%, 30%, 55%, and 65%, respectively. The median lethal dose for the WSC-MP and WSC-NP groups were 4080 mg/kg and 2370 mg/kg, respectively. Conclusion: These results indicate that CTS and WSC MPs and NPs have greater effects than commercially available CTS and WSC, and can be used as potential antiobesity agents.
Comparison of long-term clinical outcome between patients with chronic versus acute type B aortic dissection treated by implantation of a stent graft: a single-center report
Chen SL,Zhu JC,Li XB,Ye F
Patient Preference and Adherence , 2013,
Abstract: Shao-Liang Chen, Jian-Cheng Zhu, Xiao-Bo Li, Fei Ye, Jun-Jie Zhang, Zhi-Zhong Liu, Nai-Liang Tian, Song Lin, Cheng-Yu Lv Nanjing First Hospital, Nanjing Medical University, Nanjing, People's Republic of China Background: Stent grafting for treatment of type B aortic dissection has been extensively used. However, the difference in the long-term clinical outcome between patients with chronic versus acute type B aortic dissection remains unknown. This study aimed to analyze the difference in long-term clinical outcome after endovascular repair for patients with chronic (<2 weeks) versus acute (≥2 weeks) type B aortic dissection. Methods: Between May 2000 and June 2011, a total of 174 patients with type B aortic dissection (56 chronic, 118 acute) treated by endovascular repair were studied prospectively. Follow-up three-dimensional computed tomography scanning and aortoangiography were scheduled at 3–6 months after the index procedure. Propensity score matching was used to compare the difference in the endpoint between the two groups. Results: The procedure-related event rate was 18.6% in the acute group and 5.4% in the chronic group (P = 0.021), but this difference became nonsignificant after propensity score matching. At the end of follow-up (mean 2.49 years), overall and aorta-related mortality was 11.0% and 7.6%, respectively, in the acute group, and was not significantly different from that in the chronic group (3.6% and 3.6%, P = 0.148 and P = 0.506, respectively). Both false and true lumina showed significant remodeling over time, with >93% complete false-lumen thrombosis. Untreated tear and type I endoleak were predictors of clinical events during follow-up. Conclusion: Comparable long-term clinical results were achieved in patients with chronic or acute type B aortic dissection after implantation of a stent graft. Keywords: aortic dissection, endovascular repair, procedure-related events, propensity score matching
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