The Experts below are selected from a list of 100047 Experts worldwide ranked by ideXlab platform
Zhipeng Gu - One of the best experts on this subject based on the ideXlab platform.
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Development of collagen/polydopamine complexed matrix as mechanically enhanced and highly biocompatible semi-Natural Tissue engineering scaffold
Acta Biomaterialia, 2017Co-Authors: Yang Hu, Weihua Dan, Shanbai Xiong, Arvind Dhinakar, Jun Wu, Yang Kang, Zhipeng GuAbstract:To improve the mechanical properties and biocompatibility of collagen I matrix, a novel and facile strategy was developed to modify porcine acellular dermal matrix (PADM) via dopamine self-polymerization followed by collagen immobilization to enhance the biological, mechanical and physicochemical properties of PADM. Mechanism study indicated that the polymerization of dopamine onto PADM surface could be regulated by controlling the amount of hydrogen bonds forming between phenol hydroxyl (C[sbnd]OH) and nitrogen atom (N[sbnd]C[dbnd]O) within collagen fibers of PADM. The investigations of surface interactions between PDA and PADM illustrated that PDA-PADM system yielded better mechanical properties, thermal stability, surface hydrophilicity and the structural integrity of PADM was maintained after dopamine coating. Furthermore, collagen (COL) was immobilized onto the fresh PDA-PADM to fabricate the collagen-PDA-PADM (COL-PDA-PADM) complexed scaffold. The MTT assay and CLSM observation showed that COL-PDA-PADM had better biocompatibility and higher cellular attachment than pure PADM and COL-PADM without dopamine coating, thus demonstrating the efficacy of PDA as the intermediate layer. Meanwhile, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of COL-PDA-PADM were investigated by an in vivo study. The results revealed that COL-PDA-PADM could effectively promote bFGF and VEGF expression, possibly leading to enhancing the dura repairing process. Overall, this work contributed a new insight into the development of a semi-Natural Tissue engineering scaffold with high biocompatibility and good mechanical properties. Statement of Significance Obtaining scaffolds with high biocompatibility and good mechanical properties is still one of the most challenging issues in Tissue engineering. To have excellent in vitro and in vivo performance, scaffolds are desired to have similar mechanical and biological properties as the Natural extracellular matrix, such as collagen based matrix. Utilizing the surface self-crosslinking and coating strategy, we successfully obtained a novel semi-Natural platform with excellent biological and mechanical properties from porcine acellular dermal matrix (PADM), polydopamine and collagen. The results confirmed that this scaffold platform has very excellent cellular performance and very little toxicity/side effects in vivo. Therefore, this semi-Natural scaffold may be an appropriate platform for Tissue engineering and this strategy would further help to develop more robust scaffolds.
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development of collagen polydopamine complexed matrix as mechanically enhanced and highly biocompatible semi Natural Tissue engineering scaffold
Acta Biomaterialia, 2017Co-Authors: Shanbai Xiong, Arvind Dhinakar, Zhipeng Gu, Yang Hu, Jun Wu, Yang KangAbstract:Abstract To improve the mechanical properties and biocompatibility of collagen I matrix, a novel and facile strategy was developed to modify porcine acellular dermal matrix (PADM) via dopamine self-polymerization followed by collagen immobilization to enhance the biological, mechanical and physicochemical properties of PADM. Mechanism study indicated that the polymerization of dopamine onto PADM surface could be regulated by controlling the amount of hydrogen bonds forming between phenol hydroxyl (C OH) and nitrogen atom (N C O) within collagen fibers of PADM. The investigations of surface interactions between PDA and PADM illustrated that PDA-PADM system yielded better mechanical properties, thermal stability, surface hydrophilicity and the structural integrity of PADM was maintained after dopamine coating. Furthermore, collagen (COL) was immobilized onto the fresh PDA-PADM to fabricate the collagen-PDA-PADM (COL-PDA-PADM) complexed scaffold. The MTT assay and CLSM observation showed that COL-PDA-PADM had better biocompatibility and higher cellular attachment than pure PADM and COL-PADM without dopamine coating, thus demonstrating the efficacy of PDA as the intermediate layer. Meanwhile, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of COL-PDA-PADM were investigated by an in vivo study. The results revealed that COL-PDA-PADM could effectively promote bFGF and VEGF expression, possibly leading to enhancing the dura repairing process. Overall, this work contributed a new insight into the development of a semi-Natural Tissue engineering scaffold with high biocompatibility and good mechanical properties. Statement of Significance Obtaining scaffolds with high biocompatibility and good mechanical properties is still one of the most challenging issues in Tissue engineering. To have excellent in vitro and in vivo performance, scaffolds are desired to have similar mechanical and biological properties as the Natural extracellular matrix, such as collagen based matrix. Utilizing the surface self-crosslinking and coating strategy, we successfully obtained a novel semi-Natural platform with excellent biological and mechanical properties from porcine acellular dermal matrix (PADM), polydopamine and collagen. The results confirmed that this scaffold platform has very excellent cellular performance and very little toxicity/side effects in vivo . Therefore, this semi-Natural scaffold may be an appropriate platform for Tissue engineering and this strategy would further help to develop more robust scaffolds.
Firas Kobeissy - One of the best experts on this subject based on the ideXlab platform.
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Hydrogels for Advanced Stem Cell Therapies: A Biomimetic Materials Approach for Enhancing Natural Tissue Function
IEEE Reviews in Biomedical Engineering, 2019Co-Authors: Wissam Farhat, Anwarul Hasan, Lucian Lucia, Frédéric Becquart, Ali Ayoub, Firas KobeissyAbstract:Stem-cell-based therapy is a promising approach for the treatment of a myriad of diseases and injuries. However, the low rate of cell survival and the uncontrolled differentiation of the injected stem cells currently remain key challenges in advancing stem cell therapeutics. Hydrogels are biomaterials that are potentially highly effective candidates for scaffold systems for stem cells and other molecular encapsulation approaches to target in vivo delivery. Hydrogel-based strategies can potentially address several current challenges in stem cell therapy. We present a concise overview of the recent advances in applications of hydrogels in stem cell therapies, with a focus particularly on the recent advances in the design and approaches for application of hydrogels in Tissue engineering. The capability of hydrogels to either enhance the function of the transplanted stem cells by promoting their controlled differentiation or enhance the recruitment of endogenous adult stem cells to the injury site for repair is also reviewed. Finally, the importance of impacts and the desired relationship between the scaffold system and the encapsulated stem cells are discussed.
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Hydrogels for Advanced Stem Cell Therapies: A Biomimetic Materials Approach for Enhancing Natural Tissue Function
IEEE Reviews in Biomedical Engineering, 2018Co-Authors: Wissam Farhat, Anwarul Hasan, Lucian Lucia, Frédéric Becquart, Ali Ayoub, Firas KobeissyAbstract:Stem cell-based therapy is a promising approach for the treatment of a myriad of diseases and injuries. However, the low rate of cell survival and the uncontrolled differentiation of the injected stem cells currently remain as the key challenges in advancing stem cell therapeutics. Hydrogels are biomaterials that are potentially highly effective candidates for scaffold systems for stem cells and other molecular encapsulation approaches to target in vivo delivery. Hydrogel-based strategies can potentially address several current challenges in stem cell therapy. In the current review, we present a concise overview of the recent advances in applications of hydrogels in stem cell therapies, with a focus particularly on the recent advances in the design and approaches for application of hydrogels in Tissue engineering. The capability of hydrogels to either enhance the function of the transplanted stem cells by promoting their controlled differentiation or enhance the recruitment of endogenous adult stem cells to the injury site for repair is also reviewed. Finally, the importance of impacts and the desired relationship between the scaffold system and the encapsulated stem cells are discussed.
Yang Hu - One of the best experts on this subject based on the ideXlab platform.
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Development of collagen/polydopamine complexed matrix as mechanically enhanced and highly biocompatible semi-Natural Tissue engineering scaffold
Acta Biomaterialia, 2017Co-Authors: Yang Hu, Weihua Dan, Shanbai Xiong, Arvind Dhinakar, Jun Wu, Yang Kang, Zhipeng GuAbstract:To improve the mechanical properties and biocompatibility of collagen I matrix, a novel and facile strategy was developed to modify porcine acellular dermal matrix (PADM) via dopamine self-polymerization followed by collagen immobilization to enhance the biological, mechanical and physicochemical properties of PADM. Mechanism study indicated that the polymerization of dopamine onto PADM surface could be regulated by controlling the amount of hydrogen bonds forming between phenol hydroxyl (C[sbnd]OH) and nitrogen atom (N[sbnd]C[dbnd]O) within collagen fibers of PADM. The investigations of surface interactions between PDA and PADM illustrated that PDA-PADM system yielded better mechanical properties, thermal stability, surface hydrophilicity and the structural integrity of PADM was maintained after dopamine coating. Furthermore, collagen (COL) was immobilized onto the fresh PDA-PADM to fabricate the collagen-PDA-PADM (COL-PDA-PADM) complexed scaffold. The MTT assay and CLSM observation showed that COL-PDA-PADM had better biocompatibility and higher cellular attachment than pure PADM and COL-PADM without dopamine coating, thus demonstrating the efficacy of PDA as the intermediate layer. Meanwhile, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of COL-PDA-PADM were investigated by an in vivo study. The results revealed that COL-PDA-PADM could effectively promote bFGF and VEGF expression, possibly leading to enhancing the dura repairing process. Overall, this work contributed a new insight into the development of a semi-Natural Tissue engineering scaffold with high biocompatibility and good mechanical properties. Statement of Significance Obtaining scaffolds with high biocompatibility and good mechanical properties is still one of the most challenging issues in Tissue engineering. To have excellent in vitro and in vivo performance, scaffolds are desired to have similar mechanical and biological properties as the Natural extracellular matrix, such as collagen based matrix. Utilizing the surface self-crosslinking and coating strategy, we successfully obtained a novel semi-Natural platform with excellent biological and mechanical properties from porcine acellular dermal matrix (PADM), polydopamine and collagen. The results confirmed that this scaffold platform has very excellent cellular performance and very little toxicity/side effects in vivo. Therefore, this semi-Natural scaffold may be an appropriate platform for Tissue engineering and this strategy would further help to develop more robust scaffolds.
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development of collagen polydopamine complexed matrix as mechanically enhanced and highly biocompatible semi Natural Tissue engineering scaffold
Acta Biomaterialia, 2017Co-Authors: Shanbai Xiong, Arvind Dhinakar, Zhipeng Gu, Yang Hu, Jun Wu, Yang KangAbstract:Abstract To improve the mechanical properties and biocompatibility of collagen I matrix, a novel and facile strategy was developed to modify porcine acellular dermal matrix (PADM) via dopamine self-polymerization followed by collagen immobilization to enhance the biological, mechanical and physicochemical properties of PADM. Mechanism study indicated that the polymerization of dopamine onto PADM surface could be regulated by controlling the amount of hydrogen bonds forming between phenol hydroxyl (C OH) and nitrogen atom (N C O) within collagen fibers of PADM. The investigations of surface interactions between PDA and PADM illustrated that PDA-PADM system yielded better mechanical properties, thermal stability, surface hydrophilicity and the structural integrity of PADM was maintained after dopamine coating. Furthermore, collagen (COL) was immobilized onto the fresh PDA-PADM to fabricate the collagen-PDA-PADM (COL-PDA-PADM) complexed scaffold. The MTT assay and CLSM observation showed that COL-PDA-PADM had better biocompatibility and higher cellular attachment than pure PADM and COL-PADM without dopamine coating, thus demonstrating the efficacy of PDA as the intermediate layer. Meanwhile, the expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) of COL-PDA-PADM were investigated by an in vivo study. The results revealed that COL-PDA-PADM could effectively promote bFGF and VEGF expression, possibly leading to enhancing the dura repairing process. Overall, this work contributed a new insight into the development of a semi-Natural Tissue engineering scaffold with high biocompatibility and good mechanical properties. Statement of Significance Obtaining scaffolds with high biocompatibility and good mechanical properties is still one of the most challenging issues in Tissue engineering. To have excellent in vitro and in vivo performance, scaffolds are desired to have similar mechanical and biological properties as the Natural extracellular matrix, such as collagen based matrix. Utilizing the surface self-crosslinking and coating strategy, we successfully obtained a novel semi-Natural platform with excellent biological and mechanical properties from porcine acellular dermal matrix (PADM), polydopamine and collagen. The results confirmed that this scaffold platform has very excellent cellular performance and very little toxicity/side effects in vivo . Therefore, this semi-Natural scaffold may be an appropriate platform for Tissue engineering and this strategy would further help to develop more robust scaffolds.
Sawa Kostin - One of the best experts on this subject based on the ideXlab platform.
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Stem cell-mediated Natural Tissue engineering.
Journal of cellular and molecular medicine, 2009Co-Authors: Helge Möllmann, Hm M. Nef, Sandra Voss, Christian Troidl, Matthias Willmer, Sebastian Szardien, Andreas Rolf, M. Klement, Robert Voswinckel, Sawa KostinAbstract:Recently, we demonstrated that a fully differentiated Tissue developed on a ventricular septal occluder that had been implanted due to infarct-related septum rupture. We suggested that this Tissue originated from circulating stem cells. The aim of the present study was to evaluate this hypothesis and to investigate the physiological differentiation and transdifferentiation potential of circulating stem cells. We developed an animal model in which a freely floating membrane was inserted into each the left ventricle and the descending aorta. Membranes were removed after pre-specified intervals of 3 days, and 2, 6 and 12 weeks; the newly developed Tissue was evaluated using quantitative RT-PCR, immunohistochemistry and in situ hybridization. The contribution of stem cells was directly evaluated in another group of animals that were by treated with granulocyte macrophage colony-stimulating factor (GM-CSF) early after implantation. We demonstrated the time-dependent generation of a fully differentiated Tissue composed of fibroblasts, myofibroblasts, smooth muscle cells, endothelial cells and new blood vessels. Cells differentiated into early cardiomyocytes on membranes implanted in the left ventricles but not on those implanted in the aortas. Stem cell mobilization with GM-CSF led to more rapid Tissue growth and differentiation. The GM-CSF effect on cell proliferation outlasted the treat ment period by several weeks. Circulating stem cells contributed to the development of a fully differentiated Tissue on membranes placed within the left ventricle or descending aorta under physiological conditions. Early cardiomyocyte generation was identified only on membranes positioned within the left ventricle.
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Natural Tissue engineering inside a ventricular septum defect occluder
Circulation, 2006Co-Authors: Helge Möllmann, Sawa Kostin, Holger Nef, Woitek Skwara, Jutta Schaper, Christian W Hamm, Albrecht ElsasserAbstract:Eighteen days after having received conservative treatment for a myocardial infarction, a 65-year-old patient developed acute right heart failure caused by a ventricular septal rupture. Progressive multiorgan failure contraindicated open heart surgery. Therefore, we implanted a ventricular septal defect occluder via a venous approach as an emergency intervention, thereby achieving stabilization of the patient within 24 hours. After another 6 weeks, an aneurysmectomy was planned because a remarkable aneurysm of the anterior wall, including the part of the septum in which the occluder was located, was detected by echocardiography and magnetic resonance imaging. During open heart surgery, the occluder was …
Matthew J. Carré - One of the best experts on this subject based on the ideXlab platform.
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In vivo measurement of skin surface strain and sub-surface layer deformation induced by Natural Tissue stretching
Journal of the Mechanical Behavior of Biomedical Materials, 2016Co-Authors: Raman Maiti, Zing S. Lee, Lutz-christian Gerhardt, José A. Sanz-Herrera, Steve E. Franklin, Stephen J. Matcher, Robert A. Byers, Roger Lewis, Daniel Woods, Matthew J. CarréAbstract:Stratum corneum and epidermal layers change in terms of thickness and roughness with gender, age and anatomical site. Knowledge of the mechanical and tribological properties of skin associated with these structural changes are needed to aid in the design of exoskeletons, prostheses, orthotics, body mounted sensors used for kinematics measurements and in optimum use of wearable on-body devices. In this case study, optical coherence tomography (OCT) and digital image correlation (DIC) were combined to determine skin surface strain and sub-surface deformation behaviour of the volar forearm due to Natural Tissue stretching. The thickness of the epidermis together with geometry changes of the dermal-epidermal junction boundary were calculated during change in the arm angle, from flexion (90??) to full extension (180??). This posture change caused an increase in skin surface Lagrange strain, typically by 25% which induced considerable morphological changes in the upper skin layers evidenced by reduction of epidermal layer thickness (20%), flattening of the dermal-epidermal junction undulation (45-50% reduction of flatness being expressed as Ra and Rz roughness profile height change) and reduction of skin surface roughness Ra and Rz (40-50%). The newly developed method, DIC combined with OCT imaging, is a powerful, fast and non-invasive methodology to study structural skin changes in real time and the Tissue response provoked by mechanical loading or stretching.
