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Yang YW, Cheng WP, Lu JK, Dong XH, Wang CB, Zhang J, Zhao LY, Gao ZF. Timing of xenon-induced delayed postconditioning to protect against spinal cord ischaemia-reperfusion injury in rats. Br J Anaesth 2013; 113:168-76. [PMID: 24277726 DOI: 10.1093/bja/aet352] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND This study was designed to assess the neuroprotective effect of xenon-induced delayed postconditioning on spinal cord ischaemia-reperfusion injury (IRI) and to determine the time of administration for best neuroprotection in a rat model of spinal cord IRI. METHODS Fifty male rats were randomly divided equally into a sham group, control group, and three xenon postconditioning groups (n=10 per group). The control group underwent spinal cord IRI and immediately inhaled 50% nitrogen/50% oxygen for 3 h at the initiation of reperfusion. The three xenon postconditioning groups underwent the same surgical procedure and immediately inhaled 50% xenon/50% oxygen for 3 h at the initiation of reperfusion or 1 and 2 h after reperfusion. The sham operation group underwent the same surgical procedure without aortic occlusion, and inhaled 50% nitrogen/50% oxygen. Neurological function was assessed using the Basso, Beattie, and Bresnahan score at 4, 24, and 48 h of reperfusion. Histological examination was performed using Nissl staining and immunohistochemistry, and apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling staining. RESULTS Compared with the control group, the three xenon postconditioning groups showed improvements in neurological outcomes, and had more morphologically normal neurones at 48 h of reperfusion. Apoptotic cell death was reduced and the ratio of Bcl-2/Bax immunoreactivity increased in xenon-treated rats compared with controls. CONCLUSIONS Xenon postconditioning up to 2 h after reperfusion provided protection against spinal cord IRI in rats, but the greatest neuroprotection occurred with administration of xenon for 1 h at reperfusion.
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Affiliation(s)
- Y W Yang
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - W P Cheng
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - J K Lu
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - X H Dong
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - C B Wang
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - J Zhang
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - L Y Zhao
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Z F Gao
- Department of Anaesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China
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Uchegbu IF, Schätzlein AG, Cheng WP, Lalatsa A. Vaccines. Fundamentals of Pharmaceutical Nanoscience 2013. [PMCID: PMC7120629 DOI: 10.1007/978-1-4614-9164-4_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vaccines continue to offer the key line of protection against a range of infectious diseases; however, the range of vaccines currently available is limited. One key consideration in the development of a vaccine is risk-versus-benefit, and in an environment of perceived low risk, the benefit of vaccination may not be recognised. To address this, there has been a move towards the use of subunit-based vaccines, which offer low side-effect profiles but are generally weakly immunogenic. This can be compensated for by the development of effective adjuvants. Nanotechnology offers key attributes in this field through the ability of nanoparticulates to incorporate and protect antigens from rapid degradation, combined with their potential to effectively deliver the antigens to appropriate cells within the immune system. These characteristics can be exploited in the development of new adjuvants. This chapter will outline the applications of nanosystems in vaccine formulations and consider the mechanisms of action behind a range of formulations.
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Affiliation(s)
- Ijeoma F. Uchegbu
- UCL School of Pharmacy, University College London, London, United Kingdom
| | | | | | - Aikaterini Lalatsa
- School of Pharmacy & Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
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Hoskins C, Wang L, Cheng WP, Cuschieri A. Dilemmas in the reliable estimation of the in-vitro cell viability in magnetic nanoparticle engineering: which tests and what protocols? Nanoscale Res Lett 2012; 7:77. [PMID: 22247975 PMCID: PMC3275459 DOI: 10.1186/1556-276x-7-77] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 01/16/2012] [Indexed: 05/31/2023]
Abstract
Magnetic nanoparticles [MNPs] made from iron oxides have many applications in biomedicine. Full understanding of the interactions between MNPs and mammalian cells is a critical issue for their applications. In this study, MNPs were coated with poly(ethylenimine) [MNP-PEI] and poly(ethylene glycol) [MNP-PEI-PEG] to provide a subtle difference in their surface charge and their cytotoxicity which were analysed by three standard cell viability assays: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium [MTS], CellTiter-Blue and CellTiter-Glo (Promega, Southampton, UK) in SH-SY5Y and RAW 264.7 cells The data were validated by traditional trypan blue exclusion. In comparison to trypan blue manual counting, the MTS and Titer-Blue assays appeared to have consistently overestimated the viability. The Titer-Glo also experienced a small overestimation. We hypothesise that interactions were occurring between the assay systems and the nanoparticles, resulting in incorrect cell viability evaluation. To further understand the cytotoxic effect of the nanoparticles on these cells, reactive oxygen species production, lipid peroxidation and cell membrane integrity were investigated. After pegylation, the MNP-PEI-PEG possessed a lower positive surface charge and exhibited much improved biocompatibility compared to MNP-PEI, as demonstrated not only by a higher cell viability, but also by a markedly reduced oxidative stress and cell membrane damage. These findings highlight the importance of assay selection and of dissection of different cellular responses in in-vitro characterisation of nanostructures.
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Affiliation(s)
- Clare Hoskins
- Institute for Medical Science and Technology (IMSaT), Wilson House, 1 Wurzburg Loan, University of Dundee, Dundee, DD2 1FD, UK.
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Gu J, Cheng WP, Hoskins C, Lin PKT, Zhao L, Zhu L, Qu X, Yang Z. Nano self-assemblies based on cholate grafted poly-L-lysine enhanced the solubility of sterol-like drugs. J Microencapsul 2011; 28:752-62. [PMID: 21967462 DOI: 10.3109/02652048.2011.615951] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The physicochemical compatibility between amphiphilic polymers and hydrophobic drugs has been recognized as an important issue for improving the drug solubilisation in polymeric micelle formulations. In this work, poly-L-lysine (PLL) grafted by cholate pendants as the only hydrophobic moiety were synthesized in order to facilitate the solubilisation of sterol drugs. Results showed that micelles formed by cholate grafted PLL encapsulated significantly higher level of prednisolone and estradiol than palmitoylated PLL micelles, whereas the solubilisation capacity of non-sterol drug (griseofulvin) is inefficient for both polymers. This suggests that higher drug-polymer incorporation can be achieved by the inclusion of hydrophobic moieties with similar architecture as the drugs, i.e. 'drug-like' functional groups, which will be useful for the future design of colloidal systems for the encapsulation of specific drug.
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Affiliation(s)
- Jingxia Gu
- State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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Hoskins C, Lin PKT, Tetley L, Cheng WP. Novel fluorescent amphiphilic poly(allylamine) and their supramacromolecular self-assemblies in aqueous media. POLYM ADVAN TECHNOL 2011. [DOI: 10.1002/pat.1962] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Thompson C, Cheng WP, Gadad P, Skene K, Smith M, Smith G, McKinnon A, Knott R. Uptake and Transport of Novel Amphiphilic Polyelectrolyte-Insulin Nanocomplexes by Caco-2 Cells—Towards Oral Insulin. Pharm Res 2011; 28:886-96. [DOI: 10.1007/s11095-010-0345-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 12/03/2010] [Indexed: 10/18/2022]
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Hoskins C, Ouaissi M, Lima SC, Cheng WP, Loureirio I, Mas E, Lombardo D, Cordeiro-da-Silva A, Ouaissi A, Kong Thoo Lin P. In vitro and in vivo anticancer activity of a novel nano-sized formulation based on self-assembling polymers against pancreatic cancer. Pharm Res 2010; 27:2694-703. [PMID: 20872054 DOI: 10.1007/s11095-010-0268-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 08/30/2010] [Indexed: 12/15/2022]
Abstract
PURPOSE To evaluate the in vitro and in vivo pancreatic anticancer activity of a nano-sized formulation based on novel polyallylamine grafted with 5% mole cholesteryl pendant groups (CH(5)-PAA). METHODS Insoluble novel anticancer drug, Bisnaphthalimidopropyldiaaminooctane (BNIPDaoct), was loaded into CH(5)-PAA polymeric self-assemblies by probe sonication. Hydrodynamic diameters and polydispersity index measurements were determined by photon correlation spectroscopy. The in vitro cytotoxicity evaluation of the formulation was carried out by the sulforhodamine B dye assay with human pancreatic adenocarcinoma BxPC-3 cells, while for the in vivo study, Xenograff mice were used. In vitro apoptotic cell death from the drug formulation was confirmed by flow cytometric analysis. RESULTS The aqueous polymer-drug formulation had a mean hydrodynamic size of 183 nm. The drug aqueous solubility was increased from negligible concentration to 0.3 mg mL(-1). CH(5)-PAA polymer alone did not exhibit cytotoxicity, but the new polymer-drug formulation showed potent in vitro and in vivo anticancer activity. The mode of cell death in the in vitro study was confirmed to be apoptotic. The in vivo results revealed that the CH(5)-PAA alone did not have any anti-proliferative effect, but the CH(5)-PAA-drug formulation exhibited similar tumour reduction efficacy as the commercial drug, gemcitabine. CONCLUSIONS The proposed formulation shows potential as pancreatic cancer therapeutics.
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Affiliation(s)
- Clare Hoskins
- School of Pharmacy and Life Sciences, Robert Gordon University, St. Andrew Street, Aberdeen, Scotland, UK
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Abstract
BACKGROUND Growth arrest and DNA damage-inducible gene 153 (GADD153), an apoptosis regulated gene, increased during endoplasmic reticulum stress. However, the expression of GADD153 in cardiomyocytes under mechanical stress is little known. We aimed to investigate the regulation mechanism of GADD153 expression and apoptosis induced by mechanical stress in cardiomyocytes. MATERIALS AND METHODS Aorta-caval shunt was performed in adult Sprague-Dawley rats to induce volume overload. Rat neonatal cardiomyocytes grown on a flexible membrane base were stretched by vacuum to 20% of maximum elongation, at 60 cycles min(-1). RESULTS The increased ventricular dimension measured using echocardiography in the shunt group (n = 8) was reversed to normal by treatment with chaperon 4-phenylbutyric acid (PBA) (n = 8) at 500 mg kg(-1) day(-1) orally for 3 days. GADD153 protein and mRNA were up-regulated in the shunt group when compared with sham group (n = 8). Treatment with PBA reversed the protein of GADD153 to the baseline values. The TUNEL assay showed that PBA reduced the apoptosis induced by volume overload. Cyclic stretch significantly increased GADD153 protein and mRNA expression after 14 h of stretch. Addition of c-jun N-terminal kinase (JNK) inhibitor SP600125, JNK small interfering RNA and tumour necrosis factor-alpha (TNF-alpha) antibody 30 min before stretch, reduced the induction of GADD153 protein. Stretch increased, while GADD153-Mut plasmid, SP600125 and TNF-alpha antibody abolished the GADD153 promoter activity induced by stretch. GADD153 mediated apoptosis induced by stretch was reversed by GADD153 siRNA, GADD153-Mut plasmid and PBA. CONCLUSIONS Mechanical stress enhanced apoptosis and GADD153 expression in cardiomyocytes. Treatment with PBA reversed both GADD153 expression and apoptosis induced by mechanical stress in cardiomyocytes.
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Affiliation(s)
- W P Cheng
- Taipei Medical University, Taipei, Taiwan
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Thompson CJ, Ding C, Qu X, Yang Z, Uchegbu IF, Tetley L, Cheng WP. The effect of polymer architecture on the nano self-assemblies based on novel comb-shaped amphiphilic poly(allylamine). Colloid Polym Sci 2008. [DOI: 10.1007/s00396-008-1925-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cheng WP, Gray AI, Tetley L, Hang TLB, Schätzlein AG, Uchegbu IF. Polyelectrolyte Nanoparticles with High Drug Loading Enhance the Oral Uptake of Hydrophobic Compounds. Biomacromolecules 2006; 7:1509-20. [PMID: 16677033 DOI: 10.1021/bm060130l] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
In the pharmaceutical industry, orally active compounds are required to have sufficient water solubility to enable dissolution within the gastrointestinal tract prior to absorption. Limited dissolution within the gastrointestinal tract often reduces the bioavailability of hydrophobic drugs. To improve gastrointestinal tract dissolution, nonaqueous solvents are often used in the form of emulsions and microemulsions. Here, we show that oil-free polyelectrolyte nanosystems (micellar dispersions and 100-300 nm particles) prepared from poly(ethylenimines) derivatized with cetyl chains and quaternary ammonium groups are able to encapsulate high levels of hydrophobic drug (0.20 g of drug per g of polymer) for over 9 months, as demonstrated using cyclosporine A (log P = 4.3). The polyelectrolytes facilitate the absorption of hydrophobic drugs within the gastrointestinal tract by promoting drug dissolution and by a hypothesized mechanism involving paracellular drug transport. Polyelectrolyte nanoparticle drug blood levels are similar to those obtained with commercial microemulsion formulations. The polyelectrolytes do not promote absorption by inhibition of the P-glycoprotein efflux pump.
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Affiliation(s)
- Woei Ping Cheng
- Department of Pharmaceutical Sciences, Strathclyde Institute for Biological Sciences Building, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, UK
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Abstract
In the past 3 decades, research has proven the significance of competitive adsorption in the equilibrium of pollutants between solid and liquid phases. However, studies on the competitive adsorption of complex ions are very limited in spite of its important role in transporting pollutants in the natural environment. The objective of this study is to derive the thermodynamic parameters of the competitive adsorption between ferricyanide and ferrocyanide from the modified Langmuir isotherm and the triple-layer model (TLM) to determine the location of adsorption. The effects of pH, temperature, and ion concentration on competitive adsorption onto gamma-Al(2)O(3) were investigated. The results demonstrate that ferrocyanide is more competitive than ferricyanide. By comparing the derived K(app) with K(int), we inferred that the adsorption of ferricyanide and ferrocyanide onto gamma-Al(2)O(3) was achieved through outer-sphere complexation. The negative DeltaH degrees indicated that the adsorption was exothermic. The positive entropy (Delta S degrees ) was caused by the replacement and release of a greater number of smaller surface ions by adsorbed ferricyanide and ferrocyanide ions of larger size. Copyright 2000 Academic Press.
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Affiliation(s)
- WP Cheng
- Department of Safety, Health and Environmental Engineering, National Lien-Ho Institute of Technology, Miaoli, Taiwan, 36012, Republic of China
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Abstract
Ferrocyanide and ferricyanide ions have strong coagulation ability in a natural water system due to their high valences. Studies with aluminum oxide turbid waters showed significant differences in coagulation between simple ions (Cl-, SO2-4, Fe(CN)3-6, Fe(CN)4-6) and other species (H2PO-4) that interact chemically with the oxide surface. The evidence suggested that the adsorption of ferrocyanide and ferricyanide on aluminum oxide surface is an outer-sphere reaction. The linear relationship between the logarithm of the significant coagulation concentration and Schultz-Hardy ratios indicated that the coagulation obeyed the DLVO rule. Therefore, it is concluded that the coagulation of aluminum oxide by ferrocyanide and ferricyanide is essentially caused by compression of the electric double layer rather than by charge neutralization. Copyright 1999 Academic Press.
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Affiliation(s)
- WP Cheng
- Institute of Environmental Engineering, National Chiao Tung University, Hsinchu, Taiwan, 30039, Republic of China
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Li MR, Cheng WP. [Studies on the control of leaf rot disease (Rhizoctonia solani Kuhn) of Amomum compactum Soland ex Maton]. Zhongguo Zhong Yao Za Zhi 1989; 14:523-5, 573. [PMID: 2511868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This paper reports the symptoms of leaf rot disease (Rhizoctonia solani) of Amomum compactum and the relationship between the spread of the disease and the conditions of climate. It has been shown that spraying topsine-M before the disease spreads is an effective way to control.
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