The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Dong Keun Han - One of the best experts on this subject based on the ideXlab platform.
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polymers for cell Tissue anti Adhesion
Progress in Polymer Science, 2015Co-Authors: Eugene Lih, Jin Ho Lee, Yoon Ki Joung, Dong Keun HanAbstract:Abstract The appropriate anti-adhesive effect of polymers on cells or Tissues in the body is one of the essential requirements of maintaining health and protecting the body from trauma and foreign bodies. Regulating the anti-adhesive properties of biomedical polymers against cells has been considered a pivotal parameter in developing polymeric biomaterials for biomedical applications such as artificial blood vessels and cell encapsulation. Meanwhile, Tissue Adhesion barriers that can physically isolate wounds and thus effectively prevent the formation of Tissue Adhesion have been a hot topic in both research and industrial fields. This review describes the comprehensive knowledge and recent research efforts on polymers for anti-Adhesion to both cells and Tissues. The basic concepts and mechanisms for the design and performance of anti-adhesive polymers are introduced in terms of both cell and Tissue. Polymer-based approaches for anti-Adhesion to cells or Tissues are then extensively discussed.
Jin Ho Lee - One of the best experts on this subject based on the ideXlab platform.
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polymers for cell Tissue anti Adhesion
Progress in Polymer Science, 2015Co-Authors: Eugene Lih, Jin Ho Lee, Yoon Ki Joung, Dong Keun HanAbstract:Abstract The appropriate anti-adhesive effect of polymers on cells or Tissues in the body is one of the essential requirements of maintaining health and protecting the body from trauma and foreign bodies. Regulating the anti-adhesive properties of biomedical polymers against cells has been considered a pivotal parameter in developing polymeric biomaterials for biomedical applications such as artificial blood vessels and cell encapsulation. Meanwhile, Tissue Adhesion barriers that can physically isolate wounds and thus effectively prevent the formation of Tissue Adhesion have been a hot topic in both research and industrial fields. This review describes the comprehensive knowledge and recent research efforts on polymers for anti-Adhesion to both cells and Tissues. The basic concepts and mechanisms for the design and performance of anti-adhesive polymers are introduced in terms of both cell and Tissue. Polymer-based approaches for anti-Adhesion to cells or Tissues are then extensively discussed.
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prevention of postsurgical Tissue Adhesion by anti inflammatory drug loaded pluronic mixtures with sol gel transition behavior
Journal of Biomedical Materials Research Part A, 2005Co-Authors: Jin Kyeong Kim, Kyu Sang Song, Seung Moo Noh, Sung Ho Ghil, Soon Hong Yuk, Jin Ho LeeAbstract:Sol-gel transition temperature-controllable Pluronic F127/F68 mixtures including mildly crosslinked alginate and nonsteroidal anti-inflammatory drug (ibuprofen) were prepared to evaluate their potential as Tissue Adhesion barrier gels. The sol-gel transition temperatures of the Pluronic mixtures could be controlled by adjusting F127/F68 ratio and polymer concentration. The mildly crosslinked alginate with still flow property provided the residence stability of Pluronic mixture gels in the body. Ibuprofen was loaded in Pluronic mixtures to reduce inflammatory response in the body and, thus, to prevent Tissue Adhesion. The gelation temperatures of the Pluronic mixtures were not affected by the alginate but lowered by the addition of ibuprofen. The in vitro drug release behavior and in vivo peritoneal Tissue Adhesion of the Pluronic mixtures with the sol-gel transition just below body temperatures were investigated. The drug release behavior from the ibuprofen (1 wt%)-loaded Pluronic mixture gels at 37 degrees C was examined using a membrane-less dissolution model. The drug in the mixture gels was released continuously up to about 45-65% of the total loading amount during the first 7 days. For in vivo evaluation of Tissue anti-Adhesion potential, the Pluronic mixtures with/without drug were coated on the peritoneal wall defects of rats and their Tissue Adhesion extents and Tissue reactions (inflammatory response, granulation Tissue formation, and toxicity in organs) were compared. It was observed that ibuprofen has a positive effect for the peritoneal Tissue anti-Adhesion. The Pluronic F127/F68/alginate/ibuprofen mixture gel (25 wt% of F127/F68 [7/3], 1 wt% ibuprofen) was highly effective for the prevention of peritoneal Tissue Adhesion and showed a relatively low inflammatory response and non-toxicity, and thus can be a good candidate material as a coatable or injectable Tissue Adhesion barrier gel.
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Tissue anti Adhesion potential of ibuprofen loaded plla peg diblock copolymer films
Biomaterials, 2005Co-Authors: Jin Ho Lee, Ka Eul Lee, Soon Hong YukAbstract:Abstract This study was designed to evaluate the effect of polyethylene glycol (PEG) and nonsteroidal anti-inflammatory drug (ibuprofen) on the prevention of postsurgical Tissue Adhesion. For this, poly( l -lactic acid) (PLLA)–PEG diblock copolymers were synthesized by ring opening polymerization of l -lactide and methoxy polyethylene glycol (Mw 5000) of different compositions. The synthesized copolymers were characterized by gel permeation chromatography and 1H-nuclear magnetic resonance spectroscopy. PLLA–PEG copolymer films were prepared by solvent casting. The prepared copolymer films were more flexible and hydrophilic than the control PLLA film, as investigated by the measurements of glass transition temperature, water absorption content, and water contact angle. The drug release behavior from the ibuprofen (10 wt%)-loaded copolymer films was examined by high performance liquid chromatography. It was observed that the drug was released gradually up to about 40% of total loading amount after 20 days, depending on PEG composition; more drug release from the films with higher PEG compositions. In vitro cell Adhesions on the copolymer films with/without drug were compared by the culture of NIH/3T3 mouse embryo fibroblasts on the surfaces. For in vivo evaluation of Tissue anti-Adhesion potential, the copolymer films with/without drug were implanted between the cecum and peritoneal wall defects of rats and their Tissue Adhesion extents were compared. It was observed that the ibuprofen-containing PLLA–PEG films with high PEG composition (particularly PLLA113–PEG113 film with PEG composition, 50 mol%) were very effective in preventing cell or Tissue Adhesion on the film surfaces, probably owing to the synergistic effects of highly mobile, hydrophilic PEG and anti-inflammatory drug, ibuprofen.
Phillip B. Messersmith - One of the best experts on this subject based on the ideXlab platform.
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Thermal gelation and Tissue Adhesion of biomimetic hydrogels
Biomedical Materials, 2007Co-Authors: Sean A. Burke, Marsha Ritter-jones, Phillip B. MessersmithAbstract:Marine and freshwater mussels are notorious foulers of natural and manmade surfaces, secreting specialized protein adhesives for rapid and durable attachment to wet substrates. Given the strong and water-resistant nature of mussel adhesive proteins, significant potential exists for mimicking their adhesive characteristics in bioinspired synthetic polymer materials. An important component of these proteins is L-3,4-dihydroxylphenylalanine (DOPA), an amino acid believed to contribute to mussel glue solidification through oxidation and crosslinking reactions. Synthetic polymers containing DOPA residues have previously been shown to crosslink into hydrogels upon the introduction of oxidizing reagents. Here we introduce a strategy for stimuli responsive gel formation of mussel adhesive protein mimetic polymers. Lipid vesicles with a bilayer melting transition of 37 °C were designed from a mixture of dipalmitoyl and dimyristoyl phosphatidylcholines and exploited for the release of a sequestered oxidizing reagent upon heating from ambient to physiologic temperature. Colorimetric studies indicated that sodium-periodate-loaded liposomes released their cargo at the phase transition temperature, and when used in conjunction with a DOPA-functionalized poly(ethylene glycol) polymer gave rise to rapid solidification of a crosslinked polymer hydrogel. The Tissue adhesive properties of this biomimetic system were determined by in situ thermal gelation of liposome/polymer hydrogel between two porcine dermal Tissue surfaces. Bond strength measurements showed that the bond formed by the adhesive hydrogel (mean = 35.1 kPa, SD = 12.5 kPa, n = 11) was several times stronger than a fibrin glue control tested under the same conditions. The results suggest a possible use of this biomimetic strategy for repair of soft Tissues.
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thermal gelation and Tissue Adhesion of biomimetic hydrogels
Biomedical Materials, 2007Co-Authors: Sean A. Burke, Marsha Ritterjones, Bruce P Lee, Phillip B. MessersmithAbstract:Marine and freshwater mussels are notorious foulers of natural and manmade surfaces, secreting specialized protein adhesives for rapid and durable attachment to wet substrates. Given the strong and water-resistant nature of mussel adhesive proteins, significant potential exists for mimicking their adhesive characteristics in bioinspired synthetic polymer materials. An important component of these proteins is L-3,4-dihydroxylphenylalanine (DOPA), an amino acid believed to contribute to mussel glue solidification through oxidation and crosslinking reactions. Synthetic polymers containing DOPA residues have previously been shown to crosslink into hydrogels upon the introduction of oxidizing reagents. Here we introduce a strategy for stimuli responsive gel formation of mussel adhesive protein mimetic polymers. Lipid vesicles with a bilayer melting transition of 37 degrees C were designed from a mixture of dipalmitoyl and dimyristoyl phosphatidylcholines and exploited for the release of a sequestered oxidizing reagent upon heating from ambient to physiologic temperature. Colorimetric studies indicated that sodium-periodate-loaded liposomes released their cargo at the phase transition temperature, and when used in conjunction with a DOPA-functionalized poly(ethylene glycol) polymer gave rise to rapid solidification of a crosslinked polymer hydrogel. The Tissue adhesive properties of this biomimetic system were determined by in situ thermal gelation of liposome/polymer hydrogel between two porcine dermal Tissue surfaces. Bond strength measurements showed that the bond formed by the adhesive hydrogel (mean = 35.1 kPa, SD = 12.5 kPa, n = 11) was several times stronger than a fibrin glue control tested under the same conditions. The results suggest a possible use of this biomimetic strategy for repair of soft Tissues.
Karim Fawzy M Elsayed - One of the best experts on this subject based on the ideXlab platform.
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periodontal regeneration employing gingival margin derived stem progenitor cells in conjunction with il 1ra hydrogel synthetic extracellular matrix
Journal of Clinical Periodontology, 2015Co-Authors: Karim Fawzy M Elsayed, Mohamed Mekhemar, Telse Bahr, Marwa Hegab, Jan Receveur, Carola Heneweer, Benedicta E Beckbroichsitter, Stephan T Becker, Joerg WiltfangAbstract:AIM: This study investigated the periodontal regenerative potential of gingival margin-derived stem/progenitor cells (G-MSCs) in conjunction with IL-1ra-releasing hyaluronic acid synthetic extracellular matrix (HA-sECM). MATERIALS AND METHODS: Periodontal defects were induced at four sites in eight miniature pigs in the premolar/molar area (-4 weeks). Autologus G-MSCs were isolated from the free gingival margin and magnetically sorted, using anti-STRO-1 antibodies. Colony formation and multilineage differentiation potential were tested. The G-MSCs were expanded and incorporated into IL-1ra-loaded/unloaded HA-sECM. Within every miniature pig, four periodontal defects were randomly treated with IL-1ra/G-MSCs/HA-sECM (test group), G-MSCs/HA-sECM (positive-control), scaling and root planing (SRP; negative control-1) or left untreated (no-treatment group; negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR), radiographic defect volume (ΔRDV), and changes in bleeding on probing (BOP) between baseline and 16 weeks post-transplantation, as well as periodontal attachment level (PAL), junctional epithelium length (JE), connective Tissue Adhesion (CTA), cementum regeneration (CR) and bone regeneration (BR) at 16 weeks post-transplantation were evaluated. RESULTS: Isolated G-MSCs showed stem/progenitor cell characteristics. IL-1ra loaded and unloaded G-MSCs/HA-sECM showed higher ΔCAL, ΔPD, ΔGR, PAL, CR and BR as well as a lower JE compared to their negative controls and improved BOP. CONCLUSION: G-MSCs in conjunction with IL-1ra-loaded/unloaded HA-sECM show a significant periodontal regenerative potential.
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periodontal regeneration employing gingival margin derived stem progenitor cells an animal study
Journal of Clinical Periodontology, 2012Co-Authors: Karim Fawzy M Elsayed, Matthias Neuschl, Wiebke De Buhr, Sonja Salzer, Andreas Wulff, Mahmoud I Elrefai, Mona S Darhous, Stephan T Becker, Sebastian Paris, Manal ElmasryAbstract:Aim This study investigated the periodontal regenerative potential of gingival margin-derived multipotent postnatal stem/progenitor cells. Material and Methods Periodontal defects were induced at six sites in eight miniature pigs in the premolar/molar area (−4 weeks). Autologous cells isolated from the gingival margin were magnetically sorted using STRO-1 antibodies and characterized flow cytometrically for the expression of CD14, CD31, CD34, CD45, CD117 and STRO-1 surface markers. Colony formation and multilineage differentiation potential were tested. The cells were expanded and loaded on deproteinized bovine cancellous bone (DBCB) and Collagen scaffolds. Within every miniature pig, six periodontal defects were randomly treated with loaded-DBCB (test group 1), unloaded-DBCB (control group 1), loaded-Collagen scaffolds (test group 2), unloaded-Collagen scaffolds (control group 1), scaling and root planing (negative control 1) or left untreated (negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR) and radiographic defect volume (ΔRDV) between baseline and 12 weeks, as well as histological attachment level (HAL), junctional epithelium length (JE) and connective Tissue Adhesion (CTA) after 12 weeks were evaluated. Results Isolated cells showed stem/progenitor cell characteristics. Cell-loaded scaffolds showed higher ΔCAL, ΔPD, ΔGR, HAL and lower JE and CTA compared with unloaded scaffolds and negative controls. The sort of scaffold had no significant influence on the measured outcomes. Conclusion Gingival margin-derived stem/progenitor cells show significant periodontal regenerative potential.
Stephan T Becker - One of the best experts on this subject based on the ideXlab platform.
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Periodontal regeneration employing gingival margin‐derived stem/progenitor cells in conjunction with IL‐1ra‐hydrogel synthetic extracellular matrix
Journal of Clinical Periodontology, 2015Co-Authors: Karim M Fawzy El-sayed, Mohamed Mekhemar, Telse Bahr, Marwa Hegab, Jan Receveur, Carola Heneweer, Joerg Wiltfang, Benedicta Elisabeth Beck-broichsitter, Stephan T Becker, Christof DörferAbstract:AIM: This study investigated the periodontal regenerative potential of gingival margin-derived stem/progenitor cells (G-MSCs) in conjunction with IL-1ra-releasing hyaluronic acid synthetic extracellular matrix (HA-sECM). MATERIALS AND METHODS: Periodontal defects were induced at four sites in eight miniature pigs in the premolar/molar area (-4 weeks). Autologus G-MSCs were isolated from the free gingival margin and magnetically sorted, using anti-STRO-1 antibodies. Colony formation and multilineage differentiation potential were tested. The G-MSCs were expanded and incorporated into IL-1ra-loaded/unloaded HA-sECM. Within every miniature pig, four periodontal defects were randomly treated with IL-1ra/G-MSCs/HA-sECM (test group), G-MSCs/HA-sECM (positive-control), scaling and root planing (SRP; negative control-1) or left untreated (no-treatment group; negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR), radiographic defect volume (ΔRDV), and changes in bleeding on probing (BOP) between baseline and 16 weeks post-transplantation, as well as periodontal attachment level (PAL), junctional epithelium length (JE), connective Tissue Adhesion (CTA), cementum regeneration (CR) and bone regeneration (BR) at 16 weeks post-transplantation were evaluated. RESULTS: Isolated G-MSCs showed stem/progenitor cell characteristics. IL-1ra loaded and unloaded G-MSCs/HA-sECM showed higher ΔCAL, ΔPD, ΔGR, PAL, CR and BR as well as a lower JE compared to their negative controls and improved BOP. CONCLUSION: G-MSCs in conjunction with IL-1ra-loaded/unloaded HA-sECM show a significant periodontal regenerative potential.
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periodontal regeneration employing gingival margin derived stem progenitor cells in conjunction with il 1ra hydrogel synthetic extracellular matrix
Journal of Clinical Periodontology, 2015Co-Authors: Karim Fawzy M Elsayed, Mohamed Mekhemar, Telse Bahr, Marwa Hegab, Jan Receveur, Carola Heneweer, Benedicta E Beckbroichsitter, Stephan T Becker, Joerg WiltfangAbstract:AIM: This study investigated the periodontal regenerative potential of gingival margin-derived stem/progenitor cells (G-MSCs) in conjunction with IL-1ra-releasing hyaluronic acid synthetic extracellular matrix (HA-sECM). MATERIALS AND METHODS: Periodontal defects were induced at four sites in eight miniature pigs in the premolar/molar area (-4 weeks). Autologus G-MSCs were isolated from the free gingival margin and magnetically sorted, using anti-STRO-1 antibodies. Colony formation and multilineage differentiation potential were tested. The G-MSCs were expanded and incorporated into IL-1ra-loaded/unloaded HA-sECM. Within every miniature pig, four periodontal defects were randomly treated with IL-1ra/G-MSCs/HA-sECM (test group), G-MSCs/HA-sECM (positive-control), scaling and root planing (SRP; negative control-1) or left untreated (no-treatment group; negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR), radiographic defect volume (ΔRDV), and changes in bleeding on probing (BOP) between baseline and 16 weeks post-transplantation, as well as periodontal attachment level (PAL), junctional epithelium length (JE), connective Tissue Adhesion (CTA), cementum regeneration (CR) and bone regeneration (BR) at 16 weeks post-transplantation were evaluated. RESULTS: Isolated G-MSCs showed stem/progenitor cell characteristics. IL-1ra loaded and unloaded G-MSCs/HA-sECM showed higher ΔCAL, ΔPD, ΔGR, PAL, CR and BR as well as a lower JE compared to their negative controls and improved BOP. CONCLUSION: G-MSCs in conjunction with IL-1ra-loaded/unloaded HA-sECM show a significant periodontal regenerative potential.
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periodontal regeneration employing gingival margin derived stem progenitor cells an animal study
Journal of Clinical Periodontology, 2012Co-Authors: Karim Fawzy M Elsayed, Matthias Neuschl, Wiebke De Buhr, Sonja Salzer, Andreas Wulff, Mahmoud I Elrefai, Mona S Darhous, Stephan T Becker, Sebastian Paris, Manal ElmasryAbstract:Aim This study investigated the periodontal regenerative potential of gingival margin-derived multipotent postnatal stem/progenitor cells. Material and Methods Periodontal defects were induced at six sites in eight miniature pigs in the premolar/molar area (−4 weeks). Autologous cells isolated from the gingival margin were magnetically sorted using STRO-1 antibodies and characterized flow cytometrically for the expression of CD14, CD31, CD34, CD45, CD117 and STRO-1 surface markers. Colony formation and multilineage differentiation potential were tested. The cells were expanded and loaded on deproteinized bovine cancellous bone (DBCB) and Collagen scaffolds. Within every miniature pig, six periodontal defects were randomly treated with loaded-DBCB (test group 1), unloaded-DBCB (control group 1), loaded-Collagen scaffolds (test group 2), unloaded-Collagen scaffolds (control group 1), scaling and root planing (negative control 1) or left untreated (negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR) and radiographic defect volume (ΔRDV) between baseline and 12 weeks, as well as histological attachment level (HAL), junctional epithelium length (JE) and connective Tissue Adhesion (CTA) after 12 weeks were evaluated. Results Isolated cells showed stem/progenitor cell characteristics. Cell-loaded scaffolds showed higher ΔCAL, ΔPD, ΔGR, HAL and lower JE and CTA compared with unloaded scaffolds and negative controls. The sort of scaffold had no significant influence on the measured outcomes. Conclusion Gingival margin-derived stem/progenitor cells show significant periodontal regenerative potential.
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Periodontal regeneration employing gingival margin-derived stem/progenitor cells: an animal study.
Journal of Clinical Periodontology, 2012Co-Authors: Karim M Fawzy El-sayed, Matthias Neuschl, Wiebke De Buhr, Sonja Salzer, Andreas Wulff, Mona S Darhous, Mahmoud I. El-refai, Stephan T Becker, Sebastian Paris, Manal El-masryAbstract:Aim This study investigated the periodontal regenerative potential of gingival margin-derived multipotent postnatal stem/progenitor cells. Material and Methods Periodontal defects were induced at six sites in eight miniature pigs in the premolar/molar area (−4 weeks). Autologous cells isolated from the gingival margin were magnetically sorted using STRO-1 antibodies and characterized flow cytometrically for the expression of CD14, CD31, CD34, CD45, CD117 and STRO-1 surface markers. Colony formation and multilineage differentiation potential were tested. The cells were expanded and loaded on deproteinized bovine cancellous bone (DBCB) and Collagen scaffolds. Within every miniature pig, six periodontal defects were randomly treated with loaded-DBCB (test group 1), unloaded-DBCB (control group 1), loaded-Collagen scaffolds (test group 2), unloaded-Collagen scaffolds (control group 1), scaling and root planing (negative control 1) or left untreated (negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR) and radiographic defect volume (ΔRDV) between baseline and 12 weeks, as well as histological attachment level (HAL), junctional epithelium length (JE) and connective Tissue Adhesion (CTA) after 12 weeks were evaluated. Results Isolated cells showed stem/progenitor cell characteristics. Cell-loaded scaffolds showed higher ΔCAL, ΔPD, ΔGR, HAL and lower JE and CTA compared with unloaded scaffolds and negative controls. The sort of scaffold had no significant influence on the measured outcomes. Conclusion Gingival margin-derived stem/progenitor cells show significant periodontal regenerative potential.
