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Tavakoli M, Salehi H, Emadi R, Varshosaz J, Labbaf S, Seifalian AM, Sharifianjazi F, Mirhaj M. 3D printed polylactic acid-based nanocomposite scaffold stuffed with microporous simvastatin-loaded polyelectrolyte for craniofacial reconstruction. Int J Biol Macromol 2024; 258:128917. [PMID: 38134992 DOI: 10.1016/j.ijbiomac.2023.128917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/22/2023] [Accepted: 12/18/2023] [Indexed: 12/24/2023]
Abstract
Critical sized craniofacial defects are among the most challenging bone defects to repair, due to the anatomical complexity and aesthetic importance. In this study, a polylactic acid/hardystonite-graphene oxide (PLA/HTGO) scaffold was fabricated through 3D printing. In order to upgrade the 3D printed scaffold to a highly porous scaffold, its channels were filled with pectin-quaternized chitosan (Pec-QCs) polyelectrolyte solution containing 0 or 20 mg/mL of simvastatin (Sim) and then freeze-dried. These scaffolds were named FD and FD-Sim, respectively. Also, similar PLA/HTGO scaffolds were prepared and dip coated with Pec-QCs solution containing 0 or 20 mg/mL of Sim and were named DC and DC-Sim, respectively. The formation of macro/microporous structure was confirmed by morphological investigations. The release of Sim from DC-Sim and FD-Sim scaffolds after 28 days was measured as 77.40 ± 5.25 and 86.02 ± 3.63 %, respectively. Cytocompatibility assessments showed that MG-63 cells had the highest proliferation, attachment and spread on the Sim containing scaffolds, especially FD-Sim. In vivo studies on a rat calvarial defect model revealed that an almost complete recovery occurred in the group treated with FD-Sim scaffold after 8 weeks and the defect was filled with newly formed bone. The results of this study acknowledge that the FD-Sim scaffold can be a perfect candidate for calvarial defect repair.
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Affiliation(s)
- Mohamadreza Tavakoli
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Hossein Salehi
- Department of Anatomical Sciences and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Rahmatollah Emadi
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Jaleh Varshosaz
- Department of Pharmaceutics, Novel Drug Delivery Systems Research Centre, School of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Sheyda Labbaf
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd, Nanoloom Ltd, Liberum Health Ltd), London BioScience Innovation Centre, London, United Kingdom
| | - Fariborz Sharifianjazi
- Department of Natural Sciences, School of Science and Technology, University of Georgia, Tbilisi, Georgia.
| | - Marjan Mirhaj
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
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Mirhaj M, Varshosaz J, Labbaf S, Emadi R, Seifalian AM, Sharifianjazi F, Tavakoli M. Mupirocin loaded core-shell pluronic-pectin-keratin nanofibers improve human keratinocytes behavior, angiogenic activity and wound healing. Int J Biol Macromol 2023; 253:126700. [PMID: 37673152 DOI: 10.1016/j.ijbiomac.2023.126700] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 08/11/2023] [Accepted: 09/02/2023] [Indexed: 09/08/2023]
Abstract
In the current study, a core-shell nanofibrous wound dressing based on Pluronic-F127 (F127) containing 2 wt% mupirocin (Mup) core and pectin (Pec)-keratin (Kr) shell was fabricated through coaxial electrospinning technique, and the blended nanofibers were also fabricated from the same materials. The fiber diameter and specific surface area of the blended nanofibers were about 101.56 nm and 20.16 m2/g, while for core-shell nanofibers they were about 97.32 nm and 25.26 m2/g, respectively. The resultant blended and core-shell nanofibers experienced a degradation of 27.65 % and 32.28 % during 7 days, respectively. The drug release profile of core-shell nanofibers revealed a sustained release of Mup over 7 days (87.66 %), while the blended F127-Pec-Kr-Mup nanofibers had a burst release within the first few hours (89.38 % up to 48 h) and a cumulative release of 91.36 % after 7 days. Due to the controlled release of Mup, the core-shell structure significantly improved the human keratinocytes behavior, angiogenic potential and wound healing in a rat model compared to the blended structure. In conclusion, the F127-Mup/Pec-Kr core-shell nanofibrous wound dressing appears to be a promising candidate for the prevention of infection, and can potentially accelerate the recovery and healing of chronic and ischemic wounds.
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Affiliation(s)
- Marjan Mirhaj
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Jaleh Varshosaz
- Novel Drug Delivery Systems Research Centre, Department of Pharmaceutics, School of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Sheyda Labbaf
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Rahmatollah Emadi
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd, Nanoloom Ltd, Liberum Health Ltd), London BioScience Innovation Centre, London, United Kingdom
| | - Fariborz Sharifianjazi
- Department of Natural Sciences, School of Science and Technology, University of Georgia, Tbilisi 0171, Georgia.
| | - Mohamadreza Tavakoli
- Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
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Mirhaj M, Varshosaz J, Labbaf S, Emadi R, Marcus Seifalian A, Sharifianjazi F. An antibacterial Multi-Layered scaffold fabricated by 3D printing and electrospinning methodologies for skin tissue regeneration. Int J Pharm 2023; 645:123357. [PMID: 37647978 DOI: 10.1016/j.ijpharm.2023.123357] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/11/2023] [Accepted: 08/26/2023] [Indexed: 09/01/2023]
Abstract
A multi-layered scaffold can mimic the hierarchical structure of the skin, accelerate the wound healing, and protect the skin against contamination and infection. In this study, a three-layered (3L) scaffold was manufactured through a combination of 3D printing and electrospinning technique. A top layer of polyurethane (PU) nanofibrous coating for the prevention of micro-organism penetration was created through electrospining. The middle layer was prepared through the 3D printing of Pluronic F127-quaternized chitosan-silver nitrate nanoparticles (F127-QCS-AgNO3), as the porous absorbent and antibacterial layer. A bottom layer of core-shell nanofibrous structure of F127-mupirocin/pectin-keratin (F127-Mup/Pec-Kr) for tissue regeneration and enable antibacterial activity was coated onto the middle layer. A range of techniques were applied to fully characterize the resultant structure. The average tensile strength and elastic modulus of the 3L scaffold were measured as 0.65 ± 0.08 MPa and 9.37 ± 2.33 MPa, respectively. The release of Ag ions, mupirocin (Mup), and the antibacterial activity of the dressings was investigated. According to the results, the highest rate of cell adhesion and viability, and angiogenic potential among the studied samples were related to the 3L scaffold, which was also found to significantly accelerate the wound healing.
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Affiliation(s)
- Marjan Mirhaj
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
| | - Jaleh Varshosaz
- Novel Drug Delivery Systems Research Centre, Department of Pharmaceutics, School of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Sheyda Labbaf
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
| | - Rahmatollah Emadi
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd, Nanoloom Ltd, Liberum Health Ltd), London BioScience Innovation Centre, London, United Kingdom.
| | - Fariborz Sharifianjazi
- Department of Natural Sciences, School of Science and Technology, University of Georgia, Tbilisi, Georgia.
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Mirhaj M, Labbaf S, Tavakoli M, Seifalian AM. Cover Image. Int Wound J 2022. [DOI: 10.1111/iwj.13994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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5
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Afjeh-Dana E, Naserzadeh P, Moradi E, Hosseini N, Seifalian AM, Ashtari B. Correction to: Stem Cell Differentiation into Cardiomyocytes: Current Methods and Emerging Approaches. Stem Cell Rev Rep 2022; 18:2202. [PMID: 35680706 DOI: 10.1007/s12015-022-10395-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Elham Afjeh-Dana
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran
| | - Parvaneh Naserzadeh
- Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
| | - Elham Moradi
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran
- Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, 14496-14535, Tehran, Iran
| | - Nasrin Hosseini
- Neuroscience Research Centre, Iran University of Medical Sciences, Tehran, Iran.
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialisation Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, UK
| | - Behnaz Ashtari
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran.
- Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, 14496-14535, Tehran, Iran.
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran.
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Adel M, Zahmatkeshan M, Akbarzadeh A, Rabiee N, Ahmadi S, Keyhanvar P, Rezayat SM, Seifalian AM. Chemotherapeutic effects of Apigenin in breast cancer: Preclinical evidence and molecular mechanisms; enhanced bioavailability by nanoparticles. Biotechnology Reports 2022; 34:e00730. [PMID: 35686000 PMCID: PMC9171451 DOI: 10.1016/j.btre.2022.e00730] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/04/2022] [Accepted: 04/10/2022] [Indexed: 12/18/2022]
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Afjeh-Dana E, Naserzadeh P, Moradi E, Hosseini N, Seifalian AM, Ashtari B. Stem Cell Differentiation into Cardiomyocytes: Current Methods and Emerging Approaches. Stem Cell Rev Rep 2022; 18:2566-2592. [PMID: 35508757 DOI: 10.1007/s12015-021-10280-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2021] [Indexed: 12/26/2022]
Abstract
Cardiovascular diseases (CVDs) are globally known to be important causes of mortality and disabilities. Common treatment strategies for CVDs, such as pharmacological therapeutics impose serious challenges due to the failure of treatments for myocardial necrosis. By contrast, stem cells (SCs) based therapies are seen to be promising approaches to CVDs treatment. In such approaches, cardiomyocytes are differentiated from SCs. To fulfill SCs complete potential, the method should be appointed to generate cardiomyocytes with more mature structure and well-functioning operations. For heart repairing applications, a greatly scalable and medical-grade cardiomyocyte generation must be used. Nonetheless, there are some challenges such as immune rejection, arrhythmogenesis, tumorigenesis, and graft cell death potential. Herein, we discuss the types of potential SCs, and commonly used methods including embryoid bodies related techniques, co-culture, mechanical stimulation, and electrical stimulation and their applications, advantages and limitations in this field. An estimated 17.9 million people died from CVDs in 2019, representing 32 % of all global deaths. Of these deaths, 85 % were due to heart attack and stroke.
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Affiliation(s)
- Elham Afjeh-Dana
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran
| | - Parvaneh Naserzadeh
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran
| | - Elham Moradi
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran.,Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
| | - Nasrin Hosseini
- Neuroscience Research Centre, Iran University of Medical Sciences, Tehran, Iran.
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialisation Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, UK
| | - Behnaz Ashtari
- Radiation Biology Research Centre, Iran University of Medical Sciences, Tehran, Iran. .,Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran. .,Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran.
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Mirhaj M, Labbaf S, Tavakoli M, Seifalian AM. Emerging treatment strategies in wound care. Int Wound J 2022; 19:1934-1954. [PMID: 35297170 DOI: 10.1111/iwj.13786] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/05/2022] [Accepted: 03/05/2022] [Indexed: 12/20/2022] Open
Abstract
Wound healing is a complex process in tissue regeneration through which the body responds to the dissipated cells as a result of any kind of severe injury. Diabetic and non-healing wounds are considered an unmet clinical need. Currently, different strategic approaches are widely used in the treatment of acute and chronic wounds which include, but are not limited to, tissue transplantation, cell therapy and wound dressings, and the use of an instrument. A large number of literatures have been published on this topic; however, the most effective clinical treatment remains a challenge. The wound dressing involves the use of a scaffold, usually using biomaterials for the delivery of medication, autologous stem cells, or growth factors from the blood. Antibacterial and anti-inflammatory drugs are also used to stop the infection as well as accelerate wound healing. With an increase in the ageing population leading to diabetes and associated cutaneous wounds, there is a great need to improve the current treatment strategies. This research critically reviews the current advancement in the therapeutic and clinical approaches for wound healing and tissue regeneration. The results of recent clinical trials suggest that the use of modern dressings and skin substitutes is the easiest, most accessible, and most cost-effective way to treat chronic wounds with advances in materials science such as graphene as 3D scaffold and biomolecules hold significant promise. The annual market value for successful wound treatment exceeds over $50 billion US dollars, and this will encourage industries as well as academics to investigate the application of emerging smart materials for modern dressings and skin substitutes for wound therapy.
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Affiliation(s)
- Marjan Mirhaj
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.,Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, UK
| | - Sheyda Labbaf
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran
| | - Mohamadreza Tavakoli
- Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, UK
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9
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Mohammadhassan R, Ferdosi A, Malmir S, Marcus Seifalian A, Seifalian M. Nanoelicitors Application Promote Antioxidant Capacity of Asparagus officinalis (In Vitro). J Trop Life Science 2021. [DOI: 10.11594/jtls.11.03.01] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Nanoparticles recently play remarkable roles in modern agriculture and biotechnology due to specific exclusively physicochemical and biological characteristics of the particles. In recent years, nanoparticles are been using as fertilizers and elicitors to improve crops. Nutritionists are constantly seeking natural antioxidants without side effects to using for healthcare and treatment. Asparagus officinalis L. as medicinal plant treated by iron (0, 10, 50 and 100 mg/L) and selenium (0, 0.5,and 1 mg/L) nanoparticles as nano elicitors. Then the antioxidant capacity of A. officinalis L. was detected and measured by α, α-diphenyl-β-picrylhydrazyl (DPPH) assay, for assessment of the antioxidant activity. The iron nanoparticlesconcentration significantly increases the antioxidant activity of both male and female asparagus stem, as well as selenium nanoparticles. When combined iron and selenium used as nano elicitors then cause the antioxidant activity significantly decreases. But the integration of two nano elicitors (iron and selenium) decreased antioxidant capacity while the use of nano-selenium could enhance antioxidant capacity. The application of nano elicitor increased antioxidant capacity in the female stem than male.Nanoparticles recently play remarkable roles in modern agriculture and biotechnology due to specific exclusively physicochemical and biological characteristics of the particles. In recent years, nanoparticles are been using as fertilizers and elicitors to improve crops. Nutritionists are constantly seeking natural antioxidants without side effects to using for healthcare and treatment. Asparagus officinalis L. as medicinal plant treated by iron (0, 10, 50 and 100 mg/L) and selenium (0, 0.5,and 1 mg/L) nanoparticles as nano elicitors. Then the antioxidant capacity of A. officinalis L. was detected and measured by α, α-diphenyl-β-picrylhydrazyl (DPPH) assay, for assessment of the antioxidant activity. The iron nanoparticlesconcentration significantly increases the antioxidant activity of both male and female asparagus stem, as well as selenium nanoparticles. When combined iron and selenium used as nano elicitors then cause the antioxidant activity significantly decreases. But the integration of two nano elicitors (iron and selenium) decreased antioxidant capacity while the use of nano-selenium could enhance antioxidant capacity. The application of nano elicitor increased antioxidant capacity in the female stem than male.
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Khosravimelal S, Mobaraki M, Eftekhari S, Ahearne M, Seifalian AM, Gholipourmalekabadi M. Hydrogels as Emerging Materials for Cornea Wound Healing. Small 2021; 17:e2006335. [PMID: 33887108 DOI: 10.1002/smll.202006335] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/15/2020] [Indexed: 06/12/2023]
Abstract
Hydrogel biomaterials have many favorable characteristics including tuneable mechanical behavior, cytocompatibility, optical properties suitable for regeneration and restoration of the damaged cornea tissue. The cornea is a tissue susceptible to various injuries and traumas with a complicated healing cascade, in which conserving its transparency and integrity is critical. Accordingly, the hydrogels' known properties along with the stimulation of nerve and cell regeneration make them ideal scaffold for corneal tissue engineering. Hydrogels have been used extensively in clinical applications for the repair and replacement of diseased organs. The development and optimizing of novel hydrogels to repair/replace corneal injuries have been the main focus of researches within the last decade. This research aims to critically review in vitro, preclinical, as well as clinical trial studies related to corneal wound healing using hydrogels in the past 10 years, as this is considered as an emerging technology for corneal treatment. Several unique modifications of hydrogels with smart behaviors have undergone early phase clinical trials and showed promising outcomes. Financially, this considers a multibillion dollars industry and with huge interest from medical devices as well as pharmaceutical industries with several products may emerge within the next five years.
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Affiliation(s)
- Sadjad Khosravimelal
- Department of Medical Biotechnology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | - Mohammadmahdi Mobaraki
- Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, 1591634311, Iran
| | - Samane Eftekhari
- Department of Medical Biotechnology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | - Mark Ahearne
- Trinity Centre for Biomedical Engineering, School of Engineering, Trinity College Dublin, University of Dublin, Dublin, D02 R590, Republic of Ireland
| | - Alexander Marcus Seifalian
- Nanotechnology & Regenerative Medicine Commercialization Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, NW1 0NH, UK
| | - Mazaher Gholipourmalekabadi
- Cellular and Molecular Research Centre, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, 1449614535, Iran
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Seifalian AM, Tavakol S. Preventive and Therapeutic Strategies to Fight COVID-19. Curr Pharm Des 2021; 27:1547-1548. [PMID: 34060994 DOI: 10.2174/138161282713210421090237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Alexander Marcus Seifalian
- Nanotechnology and Regenerative Medicine Commercialization Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, United Kingdom
| | - Shima Tavakol
- Nanotechnology and Regenerative Medicine Commercialization Centre (NanoRegMed Ltd), London BioScience Innovation Centre, London, United Kingdom
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Valizadeh A, Asghari S, Bastani S, Sarvari R, Keyhanvar N, Razin SJ, Khiabani AY, Yousefi B, Yousefi M, Shoae-Hassani A, Mahmoodpoor A, Hamishehkar H, Tavakol S, Keshel SH, Nouri M, Seifalian AM, Keyhanvar P. Will stem cells from fat and growth factors from blood bring new hope to female patients with reproductive disorders? Reprod Biol 2021; 21:100472. [PMID: 33639342 DOI: 10.1016/j.repbio.2020.100472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 11/21/2020] [Accepted: 12/06/2020] [Indexed: 01/05/2023]
Abstract
Female reproductive system disorders (FRSD) with or without infertility are prevalent women's health problems with a variety of treatment approaches including surgery and hormone therapy. It currently considering to sub-branch of regenerative medicine including stem cells or growth factors injection-based delivery treatment might be improved female reproductive health life. The most common products used for these patients treatment are autologous cell or platelet-based products from patients, including platelet-rich plasma, plasma rich in growth factor, platelet-rich fibrin, and stromal vascular fraction. In this review, we discuss each of the above products used in treatment of FRSD and critically evaluate the clinical outcome.
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Affiliation(s)
- Amir Valizadeh
- Stem Cell Research Center, Stem Cells and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Samira Asghari
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sepideh Bastani
- Stem Cell Research Center, Stem Cells and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Raana Sarvari
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Neda Keyhanvar
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran; Gene Yakhteh Keyhan (Genik) Company (Ltd), Pharmaceutical Biotechnology Incubator, Tabriz University of Medical Sciences, Tabriz, Iran; ARTAN1100 Startup Accelerator, Tabriz, Iran
| | - Sepideh Jalilzadeh Razin
- Stem Cell Research Center, Stem Cells and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Yousefzadeh Khiabani
- Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Bahman Yousefi
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mehdi Yousefi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Shoae-Hassani
- Stem Cell and Regenerative Medicine Research Center, Iran University of Medical Sciences, Tehran, Iran; Andam Baft Yakhteh (ABY) Company (Ltd), Tehran, Iran
| | - Ata Mahmoodpoor
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamed Hamishehkar
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Shima Tavakol
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Saeed Heidari Keshel
- Medical Nanotechnology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Tissue Engineering and Applied Cell Science, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Nouri
- Stem Cell Research Center, Stem Cells and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; ARTAN1100 Startup Accelerator, Tabriz, Iran; Zist Andam Yakhteh Azerbaijan (ZAYA) Company (PHT), Medical Instrument Technology Incubator, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alexander Marcus Seifalian
- Nanotechnology and Regenerative Medicine Commercialization Centre (Ltd), The London Innovation Bio Science Centre, London NW1 0NH, United Kingdom
| | - Peyman Keyhanvar
- Stem Cell Research Center, Stem Cells and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; ARTAN1100 Startup Accelerator, Tabriz, Iran; Zist Andam Yakhteh Azerbaijan (ZAYA) Company (PHT), Medical Instrument Technology Incubator, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran; HealthNBICS Group, Convergence of Knowledge and Technology to the benefit of Society Network (CKTSN), Universal Scientific Education and Research Network (USERN), Tabriz, Iran.
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Naderi N, Griffin MF, Mosahebi A, Butler PE, Seifalian AM. Adipose derived stem cells and platelet rich plasma improve the tissue integration and angiogenesis of biodegradable scaffolds for soft tissue regeneration. Mol Biol Rep 2020; 47:2005-2013. [PMID: 32072400 PMCID: PMC7688190 DOI: 10.1007/s11033-020-05297-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 01/31/2020] [Indexed: 11/30/2022]
Abstract
Current surgical reconstruction for soft tissue replacement involves lipotransfer to restore soft tissue replacements but is limited by survival and longevity of the fat tissue. Alternative approaches to overcome these limitations include using biodegradable scaffolds with stem cells with growth factors to generate soft tissue. Adipose derived stem cells (ADSCs) offer great potential to differentiate into adipose, and can be delivered using biodegradable scaffolds. However, the optimal scaffold to maximise this approach is unknown. This study investigates the biocompatibility of nanocomposite scaffolds (POSS-PCL) to deliver ADSCs with and without the addition of growth factors using platelet rich plasma (PRP) in vivo. Rat ADSCs were isolated and then seeded on biodegradable scaffolds (POSS-PCL). In addition, donor rats were used to isolate PRP to modify the scaffolds. The implants were then subcutaneously implanted for 3-months to assess the effect of PRP and ADSC on POSS-PCL scaffolds biocompatibility. Histology after explanation was examined to assess tissue integration (H&E) and collagen production (Massons Trichome). Immunohistochemistry was used to assess angiogenesis (CD3, α-SMA), immune response (CD45, CD68) and adipose formation (PPAR-γ). At 3-months PRP-ADSC-POSS-PCL scaffolds demonstrated significantly increased tissue integration and angiogenesis compared to PRP, ADSC and unmodified scaffolds (p < 0.05). In addition, PRP-ADSC-POSS-PCL scaffolds showed similar levels of CD45 and CD68 staining compared to unmodified scaffolds. Furthermore, there was increased PPAR-γ staining demonstrated at 3-months with PRP-ADSC-POSS-PCL scaffolds (p < 0.05). POSS-PCL nanocomposite scaffolds provide an effective delivery system for ADSCs. PRP and ADSC work synergistically to enhance the biocompatibility of POSS-PCL scaffolds and provide a platform technology for soft tissue regeneration.
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Affiliation(s)
- N Naderi
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK.,Royal Free London NHS Foundation Trust Hospital, London, UK.,Plastic and Reconstructive Surgery Department, Royal Free Hospital, University College London, Pond Street, London, UK
| | - M F Griffin
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK. .,Royal Free London NHS Foundation Trust Hospital, London, UK. .,Plastic and Reconstructive Surgery Department, Royal Free Hospital, University College London, Pond Street, London, UK.
| | - A Mosahebi
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK.,Royal Free London NHS Foundation Trust Hospital, London, UK.,Plastic and Reconstructive Surgery Department, Royal Free Hospital, University College London, Pond Street, London, UK
| | - P E Butler
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK.,Royal Free London NHS Foundation Trust Hospital, London, UK.,Plastic and Reconstructive Surgery Department, Royal Free Hospital, University College London, Pond Street, London, UK
| | - A M Seifalian
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK.,Director/Professor Nanotechnology & Regenerative Medicine, NanoRegMed Ltd, London, UK
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Griffin MF, Naderi N, Kalaskar DM, Seifalian AM, Butler PE. Argon plasma surface modification promotes the therapeutic angiogenesis and tissue formation of tissue-engineered scaffolds in vivo by adipose-derived stem cells. Stem Cell Res Ther 2019; 10:110. [PMID: 30922398 PMCID: PMC6440049 DOI: 10.1186/s13287-019-1195-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/21/2019] [Accepted: 02/25/2019] [Indexed: 01/09/2023] Open
Abstract
Background Synthetic implants are being used to restore injured or damaged tissues following cancer resection and congenital diseases. However, the survival of large tissue implant replacements depends on their ability to support angiogenesis that if limited, causes extrusion and infection of the implant. This study assessed the beneficial effect of platelet-rich plasma (PRP) and adipose-derived stem cells (ADSCs) on synthetic biomaterials in combination with argon plasma surface modification to enhance vascularisation of tissue-engineered constructs. Methods Non-biodegradable polyurethane scaffolds were manufactured and modified with plasma surface modification using argon gas (PM). Donor rats were then used to extract ADSCs and PRP to modify the scaffolds further. Scaffolds with and without PM were modified with and without ADSCs and PRP and subcutaneously implanted in the dorsum of rats for 3 months. After 12 weeks, the scaffolds were excised and the degree of tissue integration using H&E staining and Masson’s trichrome staining, angiogenesis by CD31 and immune response by CD45 and CD68 immunohistochemistry staining was examined. Results H&E and Masson’s trichrome staining showed PM+PRP+ADSC and PM+ADSC scaffolds had the greatest tissue integration, but there was no significant difference between the two scaffolds (p < 0.05). The greatest vessel formation after 3 months was shown with PM+PRP+ADSC and PM+ADSC scaffolds using CD31 staining compared to all other scaffolds (p < 0.05). The CD45 and CD68 staining was similar between all scaffolds after 3 months showing the ADSCs or PRP had no effect on the immune response of the scaffolds. Conclusions Argon plasma surface modification enhanced the effect of adipose-derived stem cells effect on angiogenesis and tissue integration of polyurethane scaffolds. The combination of ADSCs and argon plasma modification may improve the survival of large tissue implants for regenerative applications. Electronic supplementary material The online version of this article (10.1186/s13287-019-1195-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- M F Griffin
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, UK. .,Royal Free London NHS Foundation Trust Hospital, London, UK. .,Charles Wolfson Center for Reconstructive Surgery, Royal Free Hospital, London, UK. .,Plastic and Reconstructive Surgery Department, Royal Free Hospital, University College London, Pond Street, London, UK.
| | - N Naderi
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, UK.,Royal Free London NHS Foundation Trust Hospital, London, UK
| | - D M Kalaskar
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, UK.,UCL Institute of Orthopaedics and Musculoskeletal Science, Division of Surgery and Interventional Science, University College London, Stanmore, Middlesex, HA7 4LP, UK
| | - A M Seifalian
- Nanotechnology and Regenerative Medicine Commercialization Centre (Ltd), The London Bioscience Innovation Centre, London, NW1 0NH, UK
| | - P E Butler
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, UK.,Royal Free London NHS Foundation Trust Hospital, London, UK.,Charles Wolfson Center for Reconstructive Surgery, Royal Free Hospital, London, UK
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15
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Nilforoushzadeh MA, Sisakht MM, Seifalian AM, Amirkhani MA, Banafshe HR, Verdi J, Sharifzad F, Taghiabadi E. Regenerative Medicine Applications in Wound Care. Curr Stem Cell Res Ther 2018; 12:658-674. [PMID: 28969578 DOI: 10.2174/1574888x12666170929123842] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 09/14/2017] [Accepted: 09/24/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND During the last two decades, a number of studies have been carried out on the application of regenerative medicine in the field of dermatology. OBJECTIVE The aim of this research was to critically review the application of regenerative medicine in the field of dermatology. The next aim was to look in depth to see whether regenerative medicine strategies have a place in the future of wound healing in a clinical setting. More specifically, to see if these strategies would apply for burns and non-healing diabetic wounds. RESULTS Billions of dollars have been spent worldwide on research in wound treatment and skin regeneration. Although a high number of clinical trials show promising results, there is still no commercially available treatment for use. In addition, the outcome data from the clinical trials, taking place throughout the world, are not published in a standardized manner. Standardization within clinical trials is required for: protocols, outcome, endpoint values, and length of follow-up. The lack of standardization makes it much more difficult to compare the data collected and the different types of treatment. CONCLUSION Despite several promising results from research and early phase clinical studies, the treatment for wounds as well as skin regeneration is still considered as an unmet clinical need. However, in the past three years, more promising research has been approaching clinical trials; this could be the solution that clinicians have been waiting for. This is a multibillion dollar industry for which there should be enough incentive for researchers and industry to seek the solution.
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Affiliation(s)
| | - Mahsa Mollapour Sisakht
- Skin and Stem Cell Research Center, Tehran University of Medical Sciences, Tehran, Iran.,Applied Cell Sciences Department, Kashan University of Medical Science, Kashan, Iran
| | - Alexander Marcus Seifalian
- Nanotechnology and Regenerative Medicine Commercialisation Centre (Ltd), The London BioScience Innovation Centre, 2 Royal College Street, London, NW10NH, United Kingdom
| | | | - Hamid Reza Banafshe
- Applied Cell Sciences Department, Kashan University of Medical Science, Kashan, Iran
| | - Javad Verdi
- Applied Cell Sciences Department, Kashan University of Medical Science, Kashan, Iran.,Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Farzaneh Sharifzad
- Applied Cell Sciences Department, Kashan University of Medical Science, Kashan, Iran.,Cancer Stem Cell Departement, Royan Institute, Tehran, Iran
| | - Ehsan Taghiabadi
- Skin and Stem Cell Research Center, Tehran University of Medical Sciences, Tehran, Iran
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16
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Griffin MF, Premakumar Y, Seifalian AM, Szarko M, Butler PEM. Biomechanical characterisation of the human nasal cartilages; implications for tissue engineering. J Mater Sci Mater Med 2016; 27:11. [PMID: 26676857 PMCID: PMC4681753 DOI: 10.1007/s10856-015-5619-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 11/04/2015] [Indexed: 05/16/2023]
Abstract
Nasal reconstruction is currently performed using autologous grafts provides but is limited by donor site morbidity, tissue availability and potentially graft failure. Additionally, current alternative alloplastic materials are limited by their high extrusion and infection rates. Matching mechanical properties of synthetic materials to the native tissue they are replacing has shown to be important in the biocompatibility of implants. To date the mechanical properties of the human nasal cartilages has not been studied in depth to be able to create tissue-engineered replacements with similar mechanical properties to native tissue. The young's modulus was characterized in compression on fresh-frozen human cadaveric septal, alar, and lateral cartilage. Due to the functional differences experienced by the various aspects of the septal cartilage, 16 regions were evaluated with an average elastic modulus of 2.72 ± 0.63 MPa. Furthermore, the posterior septum was found to be significantly stiffer than the anterior septum (p < 0.01). The medial and lateral alar cartilages were tested at four points with an elastic modulus ranging from 2.09 ± 0.81 MPa, with no significant difference between the cartilages (p < 0.78). The lateral cartilage was tested once in all cadavers with an average elastic modulus of 0.98 ± 0.29 MPa. In conclusion, this study provides new information on the compressive mechanical properties of the human nasal cartilage, allowing surgeons to have a better understanding of the difference between the mechanical properties of the individual nasal cartilages. This study has provided a reference, by which tissue-engineered should be developed for effective cartilage replacements for nasal reconstruction.
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Affiliation(s)
- M F Griffin
- Centre for Nanotechnology & Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, UK.
| | - Y Premakumar
- Anatomical Sciences, Institute for Medical and Biomedical Education, St. George's, University of London, London, UK
| | - A M Seifalian
- Centre for Nanotechnology & Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, UK
| | - M Szarko
- Anatomical Sciences, Institute for Medical and Biomedical Education, St. George's, University of London, London, UK.
| | - P E M Butler
- Centre for Nanotechnology & Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, UK
- Department of Plastic and Reconstructive Surgery, Royal Free Hampstead NHS Trust Hospital, London, UK
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Abstract
Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mechanism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing research interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaffold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerative/neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.
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Affiliation(s)
- Magdalini Tsintou
- UCL Centre for Nanotechnology & Regenerative Medicine, Division of Surgery and Interventional Science, University College of London, London, UK
| | - Kyriakos Dalamagkas
- UCL Centre for Nanotechnology & Regenerative Medicine, Division of Surgery and Interventional Science, University College of London, London, UK
| | - Alexander Marcus Seifalian
- UCL Centre for Nanotechnology & Regenerative Medicine, Division of Surgery and Interventional Science, University College of London, London, UK
- Royal Free London NHS Foundation Trust Hospital, London, UK
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Teoh GZ, Klanrit P, Kasimatis M, Seifalian AM. Role of nanotechnology in development of artificial organs. Minerva Med 2015; 106:17-33. [PMID: 25300897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Improvements in our understanding of the interactions between implants and cells have directed attention towards nanoscale technologies. To date, nanotechnology has played a helping hand in the development of synthetic artificial organs and regenerative medicine. This includes the production of smart nanocomposite materials; fluorescent nanoparticles like Quantum Dots (QD) and magnetic nano particles (MNP) for stem cell tracking; and carbon nanotubes (CNT) and graphene for enhancement of material properties. The scope of this paper includes the role of nanoparticles in the development of nanomaterials; the chemical surface modifications possible to improve implant function and an overview of the performance of nano-engineered organs thus far. This includes implants developed for aesthetic purposes like nasal and auricular scaffolds, plastic and reconstructive surgical constructs (i.e. dermal grafts), hollow organs for cardiothoracic applications; and last but not least, orthopedic implants. The five-year outlook for nano-enhanced artificial organs is also discussed, highlighting the key research and development areas, available funds and the hurdles we face in accomplishing progression from prototypes on the laboratory bench to off-the-shelf products for the consumer market. Ultimately, this review aims to delineate the advantages of incorporating nanotechnology, as an individual entity or as a part of a construct for the development of tissue engineering scaffolds and/or artificial organs, and unravel the mechanisms of tissue cell-biomaterial interactions at the nanoscale, allowing for better progress in the development and optimization of unique nanoscale surface features for a wide range of applications.
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Affiliation(s)
- G Z Teoh
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science University College London, London, UK -
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Teoh GZ, Crowley C, Birchall MA, Seifalian AM. Development of resorbable nanocomposite tracheal and bronchial scaffolds for paediatric applications. Br J Surg 2015; 102:e140-50. [DOI: 10.1002/bjs.9700] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/12/2014] [Accepted: 10/10/2014] [Indexed: 11/07/2022]
Abstract
Abstract
Background
Congenital tracheal defects and prolonged intubation following premature birth have resulted in an unmet clinical need for tracheal replacement. Advances in stem cell technology, tissue engineering and material sciences have inspired the development of a resorbable, nanocomposite tracheal and bronchial scaffold.
Methods
A bifurcated scaffold was designed and constructed using a novel, resorbable nanocomposite polymer, polyhedral oligomeric silsesquioxane poly(ϵ-caprolactone) urea urethane (POSS-PCL). Material characterization studies included tensile strength, suture retention and surface characteristics. Bone marrow-derived mesenchymal stem cells (bmMSCs) and human tracheobronchial epithelial cells (HBECs) were cultured on POSS-PCL for up to 14 days, and metabolic activity and cell morphology were assessed. Quantum dots conjugated to RGD (l-arginine, glycine and l-aspartic acid) tripeptides and anticollagen type I antibody were then employed to observe cell migration throughout the scaffold.
Results
POSS-PCL exhibited good mechanical properties, and the relationship between the solid elastomer and foam elastomer of POSS-PCL was comparable to that between the cartilaginous U-shaped rings and interconnective cartilage of the native human trachea. Good suture retention was also achieved. Cell attachment and a significant, steady increase in proliferation were observed for both cell types (bmMSCs, P = 0·001; HBECs, P = 0·003). Quantum dot imaging illustrated adequate cell penetration throughout the scaffold, which was confirmed by scanning electron microscopy.
Conclusion
This mechanically viable scaffold successfully supports bmMSC and HBEC attachment and proliferation, demonstrating its potential as a tissue-engineered solution to tracheal replacement.
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Affiliation(s)
- G Z Teoh
- Division of Surgery and Interventional Science, London, UK
- University College London Centre for Nanotechnology and Regenerative Medicine, London, UK
| | - C Crowley
- Division of Surgery and Interventional Science, London, UK
- Institute of Child Health, London, UK
| | - M A Birchall
- Ear Institute, University College London, London, UK
- Department of Surgery, Royal National Throat, Nose and Ear Hospital, London, UK
| | - A M Seifalian
- Division of Surgery and Interventional Science, London, UK
- University College London Centre for Nanotechnology and Regenerative Medicine, London, UK
- Department of Surgery, Royal Free NHS Foundation Trust Hospital, London, UK
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20
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Chong DST, Turner LA, Gadegaard N, Seifalian AM, Dalby MJ, Hamilton G. Nanotopography and plasma treatment: redesigning the surface for vascular graft endothelialisation. Eur J Vasc Endovasc Surg 2015; 49:335-43. [PMID: 25579872 DOI: 10.1016/j.ejvs.2014.12.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/05/2014] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Vascular graft materials in clinical use, such as polytetrafluoroethylene (PTFE) and Dacron, do not endothelialise and have low patency rates. The importance of an endothelial cell layer on the luminal surface of a vascular graft is well-known with surface topography and chemistry playing an important role. The aim of this study was to investigate the potential of plasma treatment and topographical structures on the luminal graft surface to enhance the self-endothelialisation potential of a nanocomposite vascular graft. METHODS POSS-PCU is a polycarbonate urea urethane (PCU) with a nanoparticle, polyhedral oligomeric silsesquioxane (POSS) incorporated within it. Planar, microgrooved, and nanopit patterned polymer films were fabricated using photolithography, electron beam lithography, reactive ion etching, and replication by solvent casting. Films were then exposed to oxygen plasma treatment at different powers for a fixed time (40 W, 60 W, 80 W/60 seconds). Effects of plasma treatment were assessed using scanning electron microscopy, atomic force microscopy and water contact angle analysis. Human umbilical vein endothelial cell (HUVEC) proliferation and morphology were characterised using immunostaining, live/dead staining, and Coomassie blue staining. RESULTS Successful embossing of the micro- and nanostructures was confirmed. Oxygen plasma treatment of the different samples showed that increasing power significantly increased the hydrophilicity of the samples (p < .0001). Improved HUVEC adhesion was seen on plasma modified compared with untreated samples (p < .0001). Coomassie blue staining showed that after 5 days, cells started to form monolayers and live/dead staining showed the cells were viable. Immunostaining showed that HUVECs expressed nitric oxide synthase on all topographies with focal adhesions appearing more pronounced on nanopit surfaces, showing retention of morphology and function. CONCLUSION These encouraging results indicate a future important role for plasma treatment and nanotopography in the development of endothelialised vascular grafts.
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Affiliation(s)
- D S T Chong
- Department of Vascular Surgery, Royal Free London NHS Foundation Trust, UK; Division of Surgery and Interventional Science, UCL, UK
| | - L A Turner
- Centre for Cell Engineering, University of Glasgow, UK
| | - N Gadegaard
- Division of Biomedical Engineering, University of Glasgow, UK
| | - A M Seifalian
- Division of Surgery and Interventional Science, UCL, UK
| | - M J Dalby
- Centre for Cell Engineering, University of Glasgow, UK
| | - G Hamilton
- Department of Vascular Surgery, Royal Free London NHS Foundation Trust, UK; Division of Surgery and Interventional Science, UCL, UK.
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Salmasi S, Seifalian AM. Intracranial aneurysms; in need of early diagnostic and treatment using bio- and nanotechnology. Curr Med Chem 2014; 21:4300-10. [PMID: 25039771 DOI: 10.2174/0929867321666140716103921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/03/2014] [Accepted: 07/11/2014] [Indexed: 11/22/2022]
Abstract
Intracranial aneurysms are present in 1-5% of population and can be described as "ticking time bombs" that can go off at any time and cause serious harms including permanent disability and death. There are two routinely practiced treatment options for this disease; endovascular coiling and surgical clipping. In recent years other promising methods, such as stent-assisted coiling, flow diverting devices and Onyx embolic agent, have also been developed and tested. The studies reviewed here suggest endovascular coiling to be the most commonly chosen treatment method and that there are reservations on using the newly developed techniques, despite studies suggesting their safety and effectiveness. Therefore, it is now becoming clear that a competent management system, in which treatment methods are chosen to best fit the characterisation of the patient and the aneurysm, should be developed in order to effectively diagnose and treat intracranial aneurysms. One way to develop such a system could be through the advancements of nanotechnology and smart materials. Neurosurgery, like many other areas of the medical field, is moving towards adopting the exciting and rapidly developing technologies based on nanomaterials as the nano-approach to detect and treat intracranial aneurysms could offer surgical opportunities that were more invasive or out of rich at the microneurosurgery level.
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22
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Yildirimer L, Seifalian AM, Butler PE. Surface and mechanical analysis of explanted Poly Implant Prosthèse silicone breast implants. Br J Surg 2013; 100:761-7. [PMID: 23475661 DOI: 10.1002/bjs.9094] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2013] [Indexed: 11/08/2022]
Abstract
BACKGROUND The recent events surrounding Poly Implant Prosthèse (PIP) breast implants have renewed the debate about the safety profile of silicone implants. The intentional use of industrial-grade instead of certified medical-grade silicone is thought to be responsible for reportedly higher frequencies of implant rupture in vivo. The differences in mechanical and viscoelastic properties between PIP and medical-grade silicone implant shells were investigated. Surface characterization of shells and gels was carried out to determine structural changes occurring after implantation. METHODS Breast implants were obtained from women at the Royal Free Hospital (London, UK). PIP implants were compared with medical-grade control silicone implants. Tensile strength, tear resistance and elongation at break were assessed using a tensile tester. Surfaces were analysed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Spearman correlation analyses and Kruskal-Wallis one-way statistical tests were performed for mechanical data. RESULTS There were 18 PIP and four medical-grade silicone implants. PIP silicone shells had significantly weaker mechanical strength than control shells (P < 0·009). There were negative correlations between mechanical properties of PIP shells and implantation times, indicative of deterioration of PIP shells over time in vivo (r(s) = -0·75, P = 0·009 for tensile strength; r(s) = -0·76, P = 0·001 for maximal strain). Comparison of ATR-FTIR spectra of PIP and control silicones demonstrated changes in material characteristics during the period of implantation suggestive of time-dependent bond breakage and degradation of the material. CONCLUSION This study demonstrated an increased weakness of PIP shells with time and therefore supports the argument for prophylactic removal of PIP breast implants.
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Affiliation(s)
- L Yildirimer
- Department of Plastic and Reconstructive Surgery, Royal Free Hospital Hampstead NHS Trust, and University College London Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery and Interventional Science, UCL, London, UK.
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Shoae-Hassani A, Mortazavi-Tabatabaei SA, Sharif S, Seifalian AM, Azimi A, Samadikuchaksaraei A, Verdi J. Differentiation of human endometrial stem cells into urothelial cells on a three-dimensional nanofibrous silk-collagen scaffold: an autologous cell resource for reconstruction of the urinary bladder wall. J Tissue Eng Regen Med 2013; 9:1268-76. [PMID: 23319462 DOI: 10.1002/term.1632] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 05/26/2012] [Accepted: 09/17/2012] [Indexed: 12/31/2022]
Abstract
Reconstruction of the bladder wall via in vitro differentiated stem cells on an appropriate scaffold could be used in such conditions as cancer and neurogenic urinary bladder. This study aimed to examine the potential of human endometrial stem cells (EnSCs) to form urinary bladder epithelial cells (urothelium) on nanofibrous silk-collagen scaffolds, for construction of the urinary bladder wall. After passage 4, EnSCs were induced by keratinocyte growth factor (KGF) and epidermal growth factor (EGF) and seeded on electrospun collagen-V, silk and silk-collagen nanofibres. Later we tested urothelium-specific genes and proteins (uroplakin-Ia, uroplakin-Ib, uroplakin-II, uroplakin-III and cytokeratin 20) by immunocytochemistry, RT-PCR and western blot analyses. Scanning electron microscopy (SEM) and histology were used to detect cell-matrix interactions. DMEM/F12 supplemented by KGF and EGF induced EnSCs to express urothelial cell-specific genes and proteins. Either collagen, silk or silk-collagen scaffolds promoted cell proliferation. The nanofibrous silk-collagen scaffolds provided a three-dimensional (3D) structure to maximize cell-matrix penetration and increase differentiation of the EnSCs. Human EnSCs seeded on 3D nanofibrous silk-collagen scaffolds and differentiated to urothelial cells provide a suitable source for potential use in bladder wall reconstruction in women.
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Affiliation(s)
- Alireza Shoae-Hassani
- Tissue Engineering and Stem Cell Department, Research Centre for Science and Technology in Medicine (RCSTiM), Tehran University of Medical Sciences, Tehran, Iran.,Applied Cell Sciences Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Abdolreza Mortazavi-Tabatabaei
- Tissue Engineering and Stem Cell Department, Research Centre for Science and Technology in Medicine (RCSTiM), Tehran University of Medical Sciences, Tehran, Iran.,Proteomics Research Centre, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shiva Sharif
- Tissue Engineering and Stem Cell Department, Research Centre for Science and Technology in Medicine (RCSTiM), Tehran University of Medical Sciences, Tehran, Iran.,Tissue Engineering Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Alexander Marcus Seifalian
- UCL Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, United Kingdom
| | - Alireza Azimi
- Department of Oncology-Pathology, Karolinska University Hospital, Stockholm, Sweden
| | - Ali Samadikuchaksaraei
- Applied Cell Sciences Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Department of Chemical Engineering, Biological Systems Engineering Laboratory, Centre for Process Systems Engineering, Imperial College London, United Kingdom
| | - Javad Verdi
- Tissue Engineering and Stem Cell Department, Research Centre for Science and Technology in Medicine (RCSTiM), Tehran University of Medical Sciences, Tehran, Iran.,Applied Cell Sciences Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Tissue Engineering Department, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Brakmane G, Winslet M, Seifalian AM. Systematic review: the applications of nanotechnology in gastroenterology. Aliment Pharmacol Ther 2012; 36:213-21. [PMID: 22686286 DOI: 10.1111/j.1365-2036.2012.05179.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 03/19/2012] [Accepted: 05/20/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND Over the past 30 years, nanotechnology has evolved dramatically. It has captured the interest of variety of fields from computing and electronics to biology and medicine. Recent discoveries have made invaluable changes to future prospects in nanomedicine; and introduced the concept of theranostics. This term offers a patient specific 'two in one' modality that comprises of diagnostic and therapeutic tools. Not only nanotechnology has shown great impact on improvements in drug delivery and imaging techniques, but also there have been several ground-breaking discoveries in regenerative medicine. AIM Gastroenterology invites multidisciplinary approach owing to high complexity of gastrointestinal (GI) system; it includes physicians, surgeons, radiologists, pharmacologists and many more. In this article, we concentrate on current developments in nano-gastroenterology. METHODS Literature search was performed using Web of Science and Pubmed search engines with terms--nanotechnology, nanomedicine and gastroenterology. Article search was concentrated on developments since 2005. RESULTS We have described original and innovative approaches in gastrointestinal drug delivery, inflammatory disease and cancer-target treatments. Here, we have reviewed advances in GI imaging using nanoparticles as fluorescent contrast, and their potential for site-specific targeting. This review has also depicted various approaches and novel discoveries in GI regenerative medicine using nanomaterials for scaffold designs and induced pluripotent stem cells as cell source. CONCLUSIONS Developments in nanotechnology have opened new range of possibilities to help our patients. This includes novel drug delivery vehicles, diagnostic tools for early and targeted disease detection and nanocomposite materials for tissue constructs to overcome cosmetic or physical disabilities.
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Affiliation(s)
- G Brakmane
- UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK
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Abstract
Lacrimal surgery in cases of severely obstructed or missing canalicular ducts is highly challenging. In these cases, the placement of a bypass tube is currently the only option to restore the drainage of tears into the nose and reduce the symptomatic watery eye. Different approaches to achieve functional drainage have been tried using blood vessels or artificial implants. The implantation of the rigid Lester Jones tube is, since its introduction in the late 1960s, the gold standard. The functional success is satisfactory. However, complication rates are high and remain, even with many modifications of the original design, a major problem. These complications include mainly the displacement and blockage of the tube, requiring regular checkups, as well as irritation of the surrounding tissue including the nose and the eye. The objective of this study was to develop a new lacrimal duct conduit (LDC) to restore structural and functional integrity of the lacrimal drainage system. The conduit is constructed with a novel polymer, polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane (POSS-PCU), that offers biocompatibility. We exploit nanotopography to evade the problems associated with current applications. A number of extrusion techniques were investigated for this purpose: ultrasonic atomization spraying, electrohydrodynamic atomization spraying/spinning, extrusion-coagulation, and high-pressure coagulation by autoclave and casting. Finally, the coagulation and cast technique were selected to construct an LDC superior to its predecessors, and its advantages highlighted.
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Affiliation(s)
- Karla Chaloupka
- Department of Ophthalmology, University Eye Hospital Zurich, Zurich, Switzerland.
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Rizvi SB, Yang SY, Bala R, Shirin G, Seifalian AM, Keshtgar M. P2-09-04: Near Infra Red Quantum Dots as Novel Probes for Sentinel Lymph Node Biopsy. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p2-09-04] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Sentinel Lymph Node Biopsy (SLNB) is a standard procedure in breast cancer surgery. The current tracers for SLNB including the blue dye and radiocolloid, have various limitations like anaphylactic reaction to the dye and exposure of radioactivity to both patients and staff. Quantum dots (QDs) are fluorescent nanoparticles (2-10nm in diameter), with unique photophysical properties like enhanced photostability and size tunable emission wavelengths, that can potentially replace the current tracers for SLNB. QDs emitting in the Near Infra Red (NIR) range of the electromagnetic spectrum can be tracked in deep tissues as biological tissues are transparent to NIR wavelengths (700-2000nm). We have developed Near Infra Red emitting Quantum Dots (NIR QDs) as alternative probes for SLNB and set up a live NIR imaging system to track them in deep tissues.
Materials and Methods: NIR emitting QDs based on CdTeHg were synthesized by a one pot aqueous method and characterized using Transmission Electron Microscopy (TEM), UV-V is*** spectrometry and photoluminescence studies. 100μl of QDs (1mg/ml) were co-injected intradermally with blue dye into the hind legs of rat models (n=4) and compared to controls (n=4) which were injected with blue dye only. The procedure was conducted under inhalational anaesthesia using isofluorane and rats were monitored for hemodynamic instability for a period of 2 hrs after injection. QDs were tracked using a live NIR imaging system including an excitation light of 630nm, emission filter of 850nm and a Hamamatsu Orca 2 UV-Vis-NIR thermoelectrically cooled CCD camera.
Results: NIR QDs had a core diameter of 7nm on TEM and emitted at 860nm upon excitation with a 630nm light source. Within 3 minutes of an intradermal injection QDs entered the lymphatic tracts. The lymphatics converged to the groin and a small surgical incision at this site revealed the underlying sentinel lymph node with minimal dissection. The rats remained hemodynamically stable throughout the duration of the procedure with no significant difference in comparison with the controls.
Conclusion: NIR emitting QDs can be used for accurate localisation of the SLN prior to surgical incision, making this an even more minimally invasive procedure and possibly an office based procedure in the future. The nanosize, surface chemistry and deep tissue visibility of these novel nanoprobes allow relentless possibilities for in vitro and in vivo molecular and cellular imaging. NIR QDs can be conjugated to biomolecules for cancer localisation, detection of micrometastasis and image guided targeted drug delivery of chemotherapeutic agents. Further studies to investigate their in vivo biodistribution are in progress to take this technology one step closer to clinical application.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-09-04.
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Affiliation(s)
- SB Rizvi
- 1University College London, London, Hampstead, United Kingdom
| | - SY Yang
- 1University College London, London, Hampstead, United Kingdom
| | - R Bala
- 1University College London, London, Hampstead, United Kingdom
| | - G Shirin
- 1University College London, London, Hampstead, United Kingdom
| | - AM Seifalian
- 1University College London, London, Hampstead, United Kingdom
| | - M Keshtgar
- 1University College London, London, Hampstead, United Kingdom
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Desai M, Gurusamy KS, Ghanbari H, Hamilton G, Seifalian AM. Remote ischaemic preconditioning versus no remote ischaemic preconditioning for vascular and endovascular surgical procedures. Cochrane Database Syst Rev 2011:CD008472. [PMID: 22161429 DOI: 10.1002/14651858.cd008472.pub2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Despite advances in perioperative care, elective major vascular surgical procedures carry a significant risk of morbidity and mortality. Remote ischaemic preconditioning is initiated by brief, non-lethal periods of ischaemia in a vascular bed different from the one which will be subjected to ischaemic insult during surgery. It has the potential to provide local tissue protection from further prolonged periods of ischaemia. OBJECTIVES The aim of this review was to compare the outcomes from vascular and endovascular surgical procedures with and without the use of remote ischaemic preconditioning. SEARCH METHODS The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (June 2011) and CENTRAL (2011, Issue 2). The authors searched MEDLINE via PubMed (July 2011), EMBASE (June 2011), and Science Citation Index Expanded (July 2011). SELECTION CRITERIA We considered for inclusion all randomised controlled trials that evaluated the role of remote ischaemic preconditioning in reducing mortality and systemic injury in patients undergoing open vascular or endovascular surgery. DATA COLLECTION AND ANALYSIS We collected the data on characteristics of the trial, methodological quality, the remote ischaemic preconditioning stimulus used, mortality, morbidity, operating time and hospital stay from each trial. We analysed the data with both the fixed-effect and the random-effects models using RevMan analysis. For each outcome we calculated the risk ratio (RR) or mean difference with 95% confidence interval (CI) based on an intention-to-treat analysis. MAIN RESULTS We included four studies with a total of 115 patients randomised to undergo a vascular procedure with remote ischaemic preconditioning and 117 patients randomised to have the procedure without remote ischaemic preconditioning. None of the trials were of low risk of bias. There was no significant difference in mortality between the two groups (RR 1.70, 95% CI 0.51 to 5.72). Similarly, there was no statistically significant difference between the two groups for all other outcomes except reduced risk of myocardial infarction in the remote ischaemic preconditioning group, which was significant by the fixed-effect model (RR 0.31, 95% CI 0.10 to 0.90) but not by the random-effects model (RR 0.34, 95% CI 0.11 to 1.08). This positive effect was from the results of only one trial and was not consistently observed. Furthermore, it was noted that there was an observed trend of high incidence of unplanned critical care admission in the remote ischaemic preconditioning group, although this was not statistically significant (RR 2.15, 95% CI 0.87 to 5.33). AUTHORS' CONCLUSIONS Based on current evidence from small pilot trials, there are too few data to be able to say whether remote ischaemic preconditioning has any beneficial or harmful effects. The safety of this technique needs to be confirmed in adequately powered trials. Therefore, further randomised trials on this technique are required.
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Affiliation(s)
- Mital Desai
- Department of Vascular Surgery, Royal Free Hampstead NHS Trust Hospital, Pond Street, London, UK, NW3 2QG
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Abstract
The use of stem cells derived from adipose tissue as an autologous and self-replenishing source for a variety of differentiated cell phenotypes, provides a great deal of promise for reconstructive surgery. In this article, we review available literature encompassing methods of extraction of pluripotent adipose stem cells (ASCs) from lipoaspirate locations, their storage, options for culture, growth and differentiation, cryopreservation and its effect on stem cell survival and proliferation, and new technologies involving biomaterials and scaffolds. We will conclude by assessing potential avenues for developing this incredibly promising field.
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Affiliation(s)
- A Wilson
- Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, UK
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Affiliation(s)
- M Loizidou
- Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, UK.
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Alobaid N, Alnaeb ME, Sales KM, Seifalian AM, Mikhailidis DP, Hamilton G. Endothelial Progenitor Cells and Their Potential Clinical Applications in Peripheral Arterial Disease. ACTA ACUST UNITED AC 2009; 12:243-50. [PMID: 16410223 DOI: 10.1080/10623320500476617] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [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: 10/25/2022]
Abstract
Endothelial progenitor cells (EPCs) were originally thought to be present only during embryonic development. New evidence suggests that they can persist into adult life, circulate in the peripheral blood and may play an important part in endothelial repair and replacement of dysfunctional endothelium. They may also play a role in the formation of new blood vessels (angiogenesis, vasculogenesis, and arteriogenesis) in ischemic tissues. In addition, EPCs have the potential to endothelialize small-diameter prosthetic vascular bypass grafts and generate a nonthrombogenic surface, thereby increasing the patency rate of these grafts. EPCs may also be used in the clinical assessment of risk of vascular disease. In this review, the authors discuss the potential use of EPCs in the management of peripheral arterial disease (PAD).
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Affiliation(s)
- N Alobaid
- Biomaterials and Tissue Engineering Centre (BTEC), Academic Division of Surgical and Interventional Sciences, University College London, London, United Kingdom
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31
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Lakhani K, Prelevic GM, Seifalian AM, Atiomo WU, Hardiman P. Polycystic ovary syndrome, diabetes and cardiovascular disease: risks and risk factors. J OBSTET GYNAECOL 2009; 24:613-21. [PMID: 16147598 DOI: 10.1080/01443610400007810] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [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: 01/08/2023]
Abstract
Polycystic ovary syndrome is one of the most common endocrine disorders in the human, affecting approximately 10% of women of reproductive age. Although originally considered a gynaecological disorder, the syndrome is associated with a wide range of endocrine and metabolic abnormalities, including insulin resistance. Affected women are at an increased risk of developing gestational and non-insulin dependent diabetes and there is an association with cardiovascular risk factors including obesity, hypertension, dyslipidaemia, hyperhomocysteinaemia, increased intima media thickness and impaired vascular elasticity. The effect on cardiovascular mortality is currently unclear. However, in view of the proven links with diabetes and the cardiovascular risk markers, this condition should be considered within the province of physicians as well as gynaecologists.
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Affiliation(s)
- K Lakhani
- Ultrasound Department X-Ray, North Middlesex Hospital, London, UK
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32
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de Mel A, Seifalian AM, Hamilton G. Nitric oxide-eluting nanocomposite vascular bypass graft. Br J Surg 2009. [DOI: 10.1002/bjs.6537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A de Mel
- Academic Division of Surgical & Interventional Sciences, UCL, Royal Free Hampstead NHS Trust Hospital, London
| | - A M Seifalian
- Academic Division of Surgical & Interventional Sciences, UCL, Royal Free Hampstead NHS Trust Hospital, London
| | - G Hamilton
- Academic Division of Surgical & Interventional Sciences, UCL, Royal Free Hampstead NHS Trust Hospital, London
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Bakhshi R, Eaton-Evans J, Edirisinghe M, Darbyshire A, You Z, Seifalian AM, Hamilton G. A novel nanocomposite polymer for the development of a new aortic stent graft. Br J Surg 2009. [DOI: 10.1002/bjs.6504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | | | | | | | - Z You
- University College, London
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34
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Tziomalos K, Tziomalos K, Sivanadarajah N, Mikhailidis DP, Boumpas DT, Seifalian AM. Increased risk of vascular events in systemic lupus erythematosus: is arterial stiffness a predictor of vascular risk? Clin Exp Rheumatol 2008; 26:1134-1145. [PMID: 19210887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Patients with systemic lupus erythematosus (SLE) have an increased vascular morbidity and mortality. Several established vascular risk factors are more prevalent in this population but cannot fully explain the reported excess atherosclerotic burden. Emerging vascular risk factors may also contribute to the increased vascular risk in these patients although the evidence is limited and often conflicting. SLE-specific risk factors also play a role in the pathogenesis of atherosclerosis.Given the multifactorial aetiology of vascular disease in SLE, an integrated index of risk could be useful in the management of these patients. Arterial stiffness possibly represents such an index and accumulating data suggest an increased prevalence of arterial stiffness in SLE. Many factors play a role in the loss of arterial elasticity in this population, including both emerging and established vascular risk factors. Arterial stiffness may emerge as a useful index for risk stratification in SLE and has the potential to guide therapeutic decisions in these patients.
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Affiliation(s)
- K Tziomalos
- Department of Clinical Biochemistry (Vascular Prevention Clinic), University College Medical School, University of London, London, U.K
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35
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Abstract
BACKGROUND A variety of local haemostatic agents is now available to stop troublesome bleeding. These agents are indicated for use during surgical interventions where conventional methods of haemostasis are not applicable because of the site of surgery or the degree of bleeding. METHOD A literature search using the PubMed and ISI Web of Knowledge databases identified relevant studies on topical haemostatic agents. Manufacturers' recommendations were also sought through commercial websites. RESULTS AND CONCLUSION A significant body of evidence now exists to support the use of topical haemostatic agents in a wide variety of clinical situations. The advantages and disadvantages of many of these agents are highlighted.
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Affiliation(s)
- H Seyednejad
- Division of Surgery and Interventional Science, University College London, UK
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36
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Punshon G, Sales KM, Vara DS, Hamilton G, Seifalian AM. Assessment of the potential of progenitor stem cells extracted from human peripheral blood for seeding a novel vascular graft material. Cell Prolif 2008; 41:321-35. [PMID: 18336476 DOI: 10.1111/j.1365-2184.2008.00523.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE A novel nanocomposite has recently been developed based on polyhedral oligomeric silsesquioxane attached by direct reaction onto a urethane segment, as a potential vascular graft material; its trade name is UCL-Nano. The UCL-Nano has been demonstrated to have similar viscoelastic properties to the walls of a natural artery, to be resistant to degradation and to be able to sustain endothelial cell seeding. Human peripheral blood contains both circulating endothelial cells and endothelial progenitor cells, which may be suitable for conduit seeding. The aim of this study was to develop a system with the potential to deliver an endothelial cell-seeded bypass graft in a realistic time frame. MATERIALS AND METHODS Endothelial progenitor cells and circulating endothelial cells were isolated from human peripheral blood and were characterized by fluorescent-activated cell sorting, reverse transcriptase-polymerase chain reaction and immunohistochemistry. Isolated cells were seeded on nanocomposite and were maintained in culture for 35 days. RESULTS The UCL-Nano was successfully seeded with cells and a confluent cell layer was achieved after 14-day culture. Cells remained viable and confluent on the nanocomposite for 35 days. CONCLUSION In conclusion, these results suggest that this process has potential both for a realistic and achievable two-stage seeding process for vascular bypass grafts and for the potential development of a device, with the aim of achieving in situ seeding once implanted.
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Affiliation(s)
- G Punshon
- Biomaterials and Tissue Engineering Centre, Academic Division of Surgical and Interventional Sciences, University College London, UK
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37
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38
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Alnaeb ME, Thompson CS, Seifalian AM, Hamilton G, Mikhailidis DP. Regional differences in the expression of nitric oxide synthase and specific receptors in the vascular tissues of control and diabetic rabbits: a pilot study. In Vivo 2007; 21:1069-1074. [PMID: 18210758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
BACKGROUND Atherosclerosis can influence the expression of endothelial nitric oxide synthase (eNOS) as well as endothelin-1 (ET-1) and 5-hydroxytryptamine (5HT; serotonin) receptors. Diabetes has an effect on the onset, severity and pattern of atherosclerosis with a predilection for more distal arteries. We aimed to identify regional differences in the distribution of eNOS activity, ET-1 and 5HT receptors in vascular tissues obtained from control and diabetic rabbits. MATERIALS AND METHODS The mid abdominal aorta, right renal and right femoral arteries were harvested from 12 adult rabbits (6 months old, 3-3.9 kg); 8 controls and 4 diabetic (induced using alloxan 7 months previously). Samples were stored in liquid nitrogen for Western immunoblotting for eNOS as well as ET-1 and 5HT receptors. RESULTS Significant differences were found in the distribution of eNOS, ET-1 and 5HT between the aorta, renal and femoral arteries in the controls. The number of ET-1 receptors was significantly higher (aorta; p=0.016, renal; p=0.004, femoral; p=0.05,) whereas, the expression of eNOS was significantly lower (aorta; p =0.004, renal; p =0.004, femoral; p =0.008) when comparing arteries from normal rabbits with these from diabetics ones. The number of 5HT receptors was higher in arteries from diabetic rabbits but this was not statistically significantly. CONCLUSION The "regional" distribution of eNOS activity as well as ET-1 and 5HT receptors in control rabbits varies significantly according to the vessel assessed. Further studies are needed to evaluate the effect of blocking these receptors (e.g. on the risk of re-stenosis). Regional receptor differences may explain why diabetes is linked with a predilection for atherosclerosis (and possibly calcification) in distal arteries.
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Affiliation(s)
- M E Alnaeb
- Vascular Unit, Royal Free Hampstead NHS Trust Hospital, London, UK
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39
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Durai R, Yang SY, Sales KM, Seifalian AM, Goldspink G, Winslet MC. Increased apoptosis and decreased proliferation of colorectal cancer cells using insulin-like growth factor binding protein-4 gene delivered locally by gene transfer. Colorectal Dis 2007; 9:625-31. [PMID: 17824980 DOI: 10.1111/j.1463-1318.2006.01190.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Insulin-like growth factor (IGF)-I induces proliferation of transformed cells. Its binding proteins (IGFBP) are involved in local regulation of IGF. This study assessed the effects of overexpression of IGFBP-4 on the development of cancer in vivo. METHOD Nude mice were subcutaneously inoculated with HT-29 colorectal cancer cells (3 x 10(6)). When the tumour became visible (1 week after inoculation), animals received either 150 microg of mammalian expression vector containing IGFBP-4 cDNA or vector alone (n = 6 each) by peritumoural injection. Tumour size was measured during the growth. After 3 weeks of IGFBP-4 induction, animals were killed and tumour tissue samples were collected for examining the level of IGFBP-4 expression. Tumour mitotic activities were determined by counting numbers of mitotic cells on the tissue section. Apoptosis was investigated by terminal deoxynucleotidyl transferase-mediated dUDP nick end labelling assay. RESULTS Following IGFBP-4 treatment, tumour showed large necrotic areas, significantly increased numbers of apoptotic cells (36.67 +/- 7.36 vs 7.07 +/- 1.91, P < 0.01 vs control), decreased cells undergoing mitosis (2.31 +/- 0.32 vs 3.61 +/- 0.27, P < 0.01 vs control) and higher expression of IGFBP-4 (P < 0.05 vs control). CONCLUSION IGFBP-4 gene transfer increased apoptosis and decreased mitosis, but tumour volume was not significantly altered possibly due to cellular debris filling the centre of tumours.
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Affiliation(s)
- R Durai
- Academic Division of Surgical and Interventional Sciences, University College London, Hampstead Campus, Royal Free Hampstead NHS Trust Hospital, London, UK
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40
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Fatourou EM, Paraskevas KI, Seifalian AM, Hamilton G, Mikhailidis DP. The role of established and emerging risk factors in peripheral vascular graft occlusion. Expert Opin Pharmacother 2007; 8:901-11. [PMID: 17472536 DOI: 10.1517/14656566.8.7.901] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [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: 11/05/2022]
Abstract
Several studies have evaluated the association between established as well as emerging vascular risk factors with peripheral graft occlusion. There is evidence for a link between the risk for graft occlusion and total serum cholesterol, low-density lipoprotein cholesterol and triglyceride levels. The overall effect of smoking shows a 2.35-fold increase in risk of graft failure. Studies involving diabetic patients undergoing peripheral bypass may have failed to detect higher occlusion rates, possibly due to increased morbidity and mortality as well as higher amputation rates even if the graft is patent. Both antiplatelet agents and anticoagulation seem to be effective in the prevention of graft occlusion. Unconvincing data have been published with regards to the effect of hypertension on graft patency. Emerging factors such as fibrinogen, lipoprotein (a), C-reactive protein and homocysteine levels should also be considered when assessing the risk of graft occlusion. More research is needed to prevent graft occlusion due to the obvious clinical relevance, quality of life and cost issues.
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Affiliation(s)
- E M Fatourou
- Department of Clinical Biochemistry, Royal Free Hospital and Royal Free University College Medical School, London, UK
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41
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Khan AN, Yang W, Seifalian AM, Winslet MC. HER2 (ErbB2) receptors, a potential therapeutic target in squamous cell carcinoma of oesophagus. Br J Cancer 2006; 94:1213-4; author reply 1214-5. [PMID: 16622443 PMCID: PMC2361248 DOI: 10.1038/sj.bjc.6603080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- A N Khan
- Academic Division of Surgical and Interventional Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF, UK
| | - W Yang
- Academic Division of Surgical and Interventional Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF, UK
| | - A M Seifalian
- Academic Division of Surgical and Interventional Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF, UK
| | - M C Winslet
- Academic Division of Surgical and Interventional Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF, UK
- Academic Division of Surgical and Interventional Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF, UK. E-mail:
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Kanoria S, Jalan R, Davies NA, Seifalian AM, Williams R, Davidson BR. Remote ischaemic preconditioning of the hind limb reduces experimental liver warm ischaemia-reperfusion injury. Br J Surg 2006; 93:762-8. [PMID: 16609953 DOI: 10.1002/bjs.5331] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [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: 12/11/2022]
Abstract
BACKGROUND Direct ischaemic preconditioning of the liver reduces ischaemia-reperfusion injury (IRI). Remote ischaemic preconditioning (RIPC) of a limb has been shown to reduce IRI to the heart. This study determined the effect of brief remote ischaemia to the limb in reducing early liver warm IRI. METHODS Twenty-eight male rabbits were allocated to four groups: sham operated, RIPC alone, IRI alone, and RIPC plus IRI. RIPC was induced in the leg with a tourniquet, before liver IRI, by three alternate cycles of 10 min ischaemia followed by 10 min reperfusion. Liver IRI was produced by total inflow occlusion for 25 min. Markers of liver injury and systemic and hepatic haemodynamics were measured for 2 h after reperfusion. RESULTS At 2 h, IRI alone was associated with increased serum levels of aminotransferases, and reduced mean arterial blood pressure, hepatic blood flow and peripheral oxygen saturation. There was significant improvement in these variables in animals that had RIPC before liver IRI, and hepatic venous nitrate/nitrite levels were also significantly higher. CONCLUSION In this experimental model RIPC appeared to reduce liver IRI.
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Affiliation(s)
- S Kanoria
- Hepatopancreatobiliary and Liver Transplant Unit, University Department of Surgery, Royal Free Hospital, London, UK
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43
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Alobaid N, Salacinski HJ, Sales KM, Ramesh B, Kannan RY, Hamilton G, Seifalian AM. Nanocomposite Containing Bioactive Peptides Promote Endothelialisation by Circulating Progenitor Cells: An In vitro Evaluation. Eur J Vasc Endovasc Surg 2006; 32:76-83. [PMID: 16466940 DOI: 10.1016/j.ejvs.2005.11.034] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2005] [Accepted: 11/13/2005] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The formation of an endothelial cell layer on the luminal surface of cardiovascular devices, especially bypass grafts, is an important attribute in order to improve their patency. Endothelial progenitor cells (EPCs) have a potential role in the endothelialisation of bypass grafts. We hypothesised that a novel approach to improve endothelialisation of bypass grafts by EPCs would be the creation on the graft lumen of a microenvironment that supports EPC adhesion and differentiation. METHODS A new generation of nanocomposite based on silsesquioxane in the form of polyhedral oligomeric silsesquioxane (POSS) nanocages which incorporate bioactive peptides (RGD) was made into sheets. Peripheral blood mononuclear cells (PBMCs) containing EPCs isolated from six consenting young, healthy, adult volunteers were then plated both on (1) sheets of the nanocomposite with the bioactive peptide, (2) sheets of the nanocomposite without the bioactive peptide, (3) culture dishes as control and then cultured in presence of vascular endothelial growth factor (VEGF). Confirmation of endothelial and EPCs markers was carried out using fluorescence-activated cell sorter (FACS) analysis, reverse transcription polymerase chain reaction (RT-PCR) and immunostaining. RESULTS One to two percent of PBMCs expressed CD34 as determined by FACS analysis. Cells were demonstrated to express mRNA for the EPC markers CD34, platelet-endothelial cell adhesion molecule-1 (CD31), CD133 and vascular endothelial growth factor receptor-2(FlK-1/KDR). Endothelial cell-colony forming units were formed between day 5 and day 7 after plating. Colonies were confirmed to be endothelial like cells by immunostaining. There were significantly greater numbers of EPC colonies on the bioactive nanocomposites as compared to the nanocomposite alone and the uncoated dishes. CONCLUSION We report a new nanocomposite based biomaterial that has been demonstrated, in vitro, to promote endothelialisation from PBMCs containing EPCs.
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Affiliation(s)
- N Alobaid
- Academic Division of Surgical and Interventional Sciences, Biomaterials and Tissue Engineering Centre (BTEC), University College London, Hampstead Campus, London NW3 2PF, UK
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Abstract
BACKGROUND Tissue engineering techniques have been employed successfully in the management of wounds, burns and cartilage repair. Current prosthetic alternatives to autologous vascular bypass grafts remain poor in terms of patency and infection risk. Growing biological blood vessels has been proposed as an alternative. METHODS This review is based on a literature search using Medline, PubMed, ISIS and CAS of original articles and reviews, and unpublished material and abstracts. RESULTS AND CONCLUSIONS Complete incorporation into host tissues and the maintenance of a viable and self-renewing endothelial layer are the fundamental goals to be achieved when developing a tissue-engineered blood vessel. Sourcing of cells and modulating their interaction with extracellular matrix and supporting scaffold have been the focus of intense research. Although the use of tissue-engineered blood vessels in humans is so far limited, advances in our knowledge of stem cell precursors and the development of new biomaterials should enable this technology to reach routine clinical practice within a decade.
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Affiliation(s)
- M S Baguneid
- Department of Vascular Surgery, Manchester Royal Infirmary and Medical School, Manchester, UK
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Sarkar S, Salacinski HJ, Hamilton G, Seifalian AM. The mechanical properties of infrainguinal vascular bypass grafts: their role in influencing patency. Eur J Vasc Endovasc Surg 2006; 31:627-36. [PMID: 16513376 DOI: 10.1016/j.ejvs.2006.01.006] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Accepted: 01/08/2006] [Indexed: 11/18/2022]
Abstract
When autologous vein is unavailable, prosthetic graft materials, particularly expanded polytetrafluoroethylene are used for peripheral arterial revascularisation. Poor long term patency of prosthetic materials is due to distal anastomotic intimal hyperplasia. Intimal hyperplasia is directly linked to shear stress abnormalities at the vessel wall. Compliance and calibre mismatch between native vessel and graft, as well as anastomotic line stress concentration contribute towards unnatural wall shear stress. High porosity reduces graft compliance by causing fibrovascular infiltration, whereas low porosity discourages the development of an endothelial lining and hence effective antithrombogenicity. Therefore, consideration of mechanical properties is necessary in graft development. Current research into synthetic vascular grafts concentrates on simulating the mechanical properties of native arteries and tissue engineering aims to construct a new biological arterial conduit.
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Affiliation(s)
- S Sarkar
- Academic Division of Surgical and Interventional Sciences, Biomaterials and Tissue Engineering Centre (BTEC), University College London, London, UK
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46
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Mallick IH, Yang W, Winslet MC, Seifalian AM. Ischaemic preconditioning improves microvascular perfusion and oxygenation following reperfusion injury of the intestine. Br J Surg 2005; 92:1169-76. [PMID: 16044427 DOI: 10.1002/bjs.4988] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [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: 12/31/2022]
Abstract
BACKGROUND Ischaemia-reperfusion (IR) injury of the intestine occurs commonly during abdominal surgery. Ischaemic preconditioning (IPC) provides a way of protecting the organ from damage inflicted by IR. This study was designed to evaluate the beneficial effect of IPC, focusing on the intestinal microcirculation and oxygenation in intestinal IR injury. METHODS Rats were allocated to three groups. Animals in the IR and IPC groups underwent 30 min of intestinal ischaemia followed by 2 h of reperfusion. In the IPC group this was preceded by 10 min of ischaemia and 10 min of reperfusion. Animals in the third group underwent laparotomy but no vascular occlusion. Intestinal microvascular perfusion, oxygenation and portal venous blood flow (PVF) were monitored continuously. At the end of the reperfusion period, blood samples were obtained for measurement of lactate dehydrogenase (LDH) and biopsies of ileum for histological evaluation. RESULTS : IPC improved intestinal microvascular perfusion and tissue oxygenation significantly at the end of the reperfusion period (P < 0.001). PVF improved significantly in the IPC compared with the IR group (P = 0.005). The serum LDH concentration was significantly lower in the IPC than the IR group (mean(s.e.m.) 667.1(86.8) versus 1973.8(306.5) U/l; P < 0.001) Histological examination showed that ileal mucosa was significantly less injured in the IPC group. CONCLUSIONS This study demonstrated that IPC improves intestinal microvascular perfusion and oxygenation.
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Affiliation(s)
- I H Mallick
- Gastrointestinal and Hepatobiliary Research Unit, University Department of Surgery, Royal Free and University College Medical School, University College London, UK
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47
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Abstract
BACKGROUND Polycystic ovary syndrome (PCOS) is associated with multiple cardiovascular risk factors and an increased prevalence of arterial dysfunction. However, microvascular dysfunction in PCOS has not been assessed. METHODS Subjects comprised 12 women with PCOS and 12 age-matched controls with normal ovaries. Microvascular function was assessed by observing forearm skin microvascular erythrocyte flux responses, to cumulative iontophoretic doses of 1% (w/v) acetylcholine (ACh) and 1% (w/v) sodium nitroprusside (SNP), using laser Doppler imaging. RESULTS Basal microvascular perfusion was comparable in PCOS and controls. The increase in skin microvascular perfusion in response to ACh was however generally blunted in PCOS women (P = 0.018). Peak ACh-induced erythrocyte flux was also less (p < 0.04) in PCOS women (125.1 +/- 21.7, i.e. 5.3-fold basal flux) than in controls (200.8 +/- 28.5, i.e. 8.3-fold basal flux). Analysis of covariance indicated this effect was unrelated to differences in body mass index or serum testosterone but serum insulin may be a weak confounder. No differences were noted between the PCOS and control groups in their response to SNP. CONCLUSION Despite its limited sample size studied, this is the first demonstration that women with PCOS exhibit microvascular endothelial dysfunction, indicated by an inhibited vasodilatory response to ACh.
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Affiliation(s)
- K Lakhani
- Ultrasound Department, North Middlesex Hospital, London
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48
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Habib MM, Hafez TS, Parkes HG, Seifalian AM, Fuller BJ, Davidson BR. A comparison of bile composition from heart-beating and non-heart-beating rabbit organ donors during normothermic extracorporeal liver perfusion: experimental evaluation using proton magnetic resonance spectroscopy. Transplant Proc 2005; 36:2914-6. [PMID: 15686659 DOI: 10.1016/j.transproceed.2004.10.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [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: 10/25/2022]
Abstract
BACKGROUND Organs retrieved from marginal and non-heart-beating donors (NHBDs) have sustained variable degrees of preretrieval damage that result in an increased incidence of complications. Normothermic extracorporeal liver perfusion (NELP) provides an opportunity to evaluate and resuscitate such organs. The aim of this study was to identify markers of ischemic injury in bile during perfusion of livers from heart-beating donors (HBDs) and NHBDs. METHODS Livers were retrieved from New Zealand white rabbits. The HBD group (n=4) had no in situ warm ischemia before retrieval and the NHBD group (n=4), 45 minutes of in situ warm ischemia before liver retrieval. After 40 minutes of postretrieval cold ischemia, all livers were dual vessel reperfused, normothermically with oxygenated buffer solution supplemented with rabbit red blood cells, for 6 hours. Bile was collected and examined with 1HMRS. RESULTS Perfusion bile from HBD group showed an increased concentration of bile acids, lactate, glucose, and phosphatidylcholine, but a decreased concentration of acetate as compared to retrieval bile. This trend was further enhanced in NHBD group. The mean +/- SD (in micromol/L) were bile acids (10.48 +/- 2.8 vs 26.05 +/- 12.1 vs 44.5 +/- 44.5), lactate (10.66 +/- 4.5 vs 14.66 +/- 5.2 vs 13.22 +/- 1.8), glucose (5.37 +/- 2 vs 21.2 +/- 5.0 vs 29.09 +/- 15.3), phosphatidylcholine (0.21 +/- 0.02 vs 5.57 +/- 1.7 vs 6.42 +/- 0.3), and acetate (1.8 +/- 0.5 vs 0.39 +/- 0.1 vs 0.38 +/- 0.09) for retrieval bile, HBD perfusion bile, and NHBD perfusion bile, respectively. One animal from each group did not produce any bile during perfusion. CONCLUSIONS 1HMRS of biliary constituents revealed differences with the type of ischemia. These indices may be potential markers of the extent of warm ischemic injury and the functional activity of an extracorporeally perfused liver.
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Affiliation(s)
- M M Habib
- University Department of Surgery, Royal Free and University College Medical School, University College, London, UK
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Kanoria S, Glantzounis G, Jalan R, Davies NA, Seifalian AM, Williams R, Davidson BR. A model to study total hepatic ischemia-reperfusion injury. Transplant Proc 2005; 36:2586-9. [PMID: 15621096 DOI: 10.1016/j.transproceed.2004.10.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Most experimental animal models for studying hepatic ischemia-reperfusion injury (IRI) involve partial or segmental ischemia of the liver or a portocaval shunt procedure to avoid mesenteric congestion. However, these do not reflect the global ischemia that occurs during liver transplantation. A rabbit model of total hepatic ischemia without a portocaval shunt is described. METHODS Twenty male New Zealand white rabbits (3.5 +/- 0.3 kg) were allocated to four groups: group 1 (n = 5), sham-operated; group 2 (n = 5), 20-minute total hepatic ischemia; group 3 (n = 5), 25-minute total hepatic ischemia; and group 4 (n = 5), 30-minute total hepatic ischemia. Total hepatic ischemia was induced by occluding the portal inflow vessels (portal vein and artery) with an atraumatic vascular loop and were measurements taken for 2 hours during reperfusion. RESULTS A total hepatic ischemia of 30 minutes caused severe liver injury resulting in cardiac arrest at 2 hours of reperfusion in all five animals due to metabolic acidosis. Twenty minutes of total ischemia was tolerated and did not produce significant liver injury. Twenty-five minutes of total ischemia was tolerated but at 2 hours of reperfusion, resulted in significant liver injury (68 +/- 41, 283.0 +/- 20.5, and 835.2 +/- 52.7 U/L) compared with the sham-operated group (serum ALT, 25.4 +/- 2.7; serum AST, 47.4 +/- 3.0; serum LDH, 307.6 +/- 44.4 U/L; P < .003). CONCLUSIONS Rabbits can tolerate 25 minutes of total hepatic ischemia without a portosystemic shunt. This 25-minute ischemia model simulates operative conditions during liver transplantation and will be valuable in studies modulating IRI.
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Affiliation(s)
- S Kanoria
- Hepato-biliary and Liver Transplant Unit, Academic Department of Surgery, Royal Free Hospital, London NW3 2QG, UK
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50
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Abstract
An intact vascular endothelium is critical to the maintenance of normal arterial tone and coagulation status. Endothelial injury leading to dysfunction is thought to be a precursor to most if not all vascular disease, and has been implicated as a critical event in atherosclerosis. At present there are several methods available for detection of in vivo endothelial function, and the aim of this study was to critically review these methods. Five distinct methods were identified and studied in detail. These methods are diverse and each assesses a different vascular bed. Importantly there is no uniformity among investigators over choice of method and protocol, making it difficult to compare in vivo enothelial dysfunction between groups. These issues need to be addressed in large scale comparative analyses so that investigators can agree a common approach to endothelial function assessment.
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Affiliation(s)
- T A Alam
- University Department of Surgery, Royal Free and University College Medical School, University College London and The Royal Free Hospital, London, UK.
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