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Frederick Grinnell - One of the best experts on this subject based on the ideXlab platform.

  • modulation of fibroblast morphology and adhesion during Collagen Matrix remodeling
    Molecular Biology of the Cell, 2002
    Co-Authors: Elisa Tamariz, Frederick Grinnell
    Abstract:

    When fibroblasts are placed within a three-dimensional Collagen Matrix, cell locomotion results in translocation of the flexible Collagen fibrils of the Matrix, a remodeling process that has been implicated in Matrix morphogenesis during development and wound repair. In the current experiments, we studied formation and maturation of cell–Matrix interactions under conditions in which we could distinguish local from global Matrix remodeling. Local remodeling was measured by the movement of Collagen-embedded beads towards the cells. Global remodeling was measured by Matrix contraction. Our observations show that no direct relationship occurs between protrusion and retraction of cell extensions and Collagen Matrix remodeling. As fibroblasts globally remodel the Collagen Matrix, however, their overall morphology changes from dendritic to stellate/bipolar, and cell–Matrix interactions mature from punctate to focal adhesion organization. The less well organized sites of cell–Matrix interaction are sufficient for translocating Collagen fibrils, and focal adhesions only form after a high degree of global remodeling occurs in the presence of growth factors. Rho kinase activity is required for maturation of fibroblast morphology and formation of focal adhesions but not for translocation of Collagen fibrils.

  • fibroblast Collagen Matrix contraction growth factor signalling and mechanical loading
    Trends in Cell Biology, 2000
    Co-Authors: Frederick Grinnell
    Abstract:

    Abstract Fibroblast–Collagen-Matrix contraction provides a unique way to study reciprocal geometric and mechanical interactions between fibroblasts and extracellular Matrix. Such interactions are difficult to appreciate or examine in routine cell culture because the culture surface is usually fixed in place. Forces exerted on Collagen fibrils by cells cause isometric tension to develop in the cells if the Collagen resists deformation; by contrast, the cells remain mechanically unloaded in the absence of Matrix resistance. Recent evidence suggests that the state of cellular mechanical loading determines the mechanism that cells use to regulate contraction.

Zongguang Wang - One of the best experts on this subject based on the ideXlab platform.

  • Alignment of osteoblast-like cells and cell-produced Collagen Matrix induced by nanogrooves.
    Tissue Engineering, 2005
    Co-Authors: Qinghua Lu, Jun Hu, Zongguang Wang
    Abstract:

    Alignment of bone cells and Collagen Matrix is closely related to the anisotropic mechanical properties of bone. Intact scaffolds that promote osteoblast differentiation and mineralization in the preferred direction offer promise in the generation of biomimetic bone tissue. In this study, we examined the alignment of osteoblast-like cells and Collagen fibers guided by nanogrooves. Nanoscale groove–ridge patterns (∼300 nm in periodicity, 60–70 nm in depth) on the surface of polystyrene (PS) were made by polarized Nd:YAG laser irradiation, at a wavelength of 266 nm. The influence of such "nanoscale features" on the orientation and alignment of cells and their mineralized Collagen Matrix was investigated, using rabbit mesenchymal stem cell (MSC)-derived osteoblast-like cells. The cells and actin stress fibers were aligned and elongated along the direction of the nanogrooves. In addition, the alignment of Collagen Matrix was also influenced by underlying nanogrooves. The results suggested that nanoscale fibro...

  • Alignment of Osteoblast-Like Cells and Cell-Produced Collagen Matrix Induced by Nanogrooves
    Tissue Engineering, 2005
    Co-Authors: Bangshang Zhu, Jie Yin, Qinghua Lu, Jun Hu, Zongguang Wang
    Abstract:

    Alignment of bone cells and Collagen Matrix is closely related to the anisotropic mechanical properties of bone. Intact scaffolds that promote osteoblast differentiation and mineralization in the preferred direction offer promise in the generation of biomimetic bone tissue. In this study, we examined the alignment of osteoblast-like cells and Collagen fibers guided by nanogrooves. Nanoscale groove-ridge patterns (∼300 nm in periodicity, 60-70 nm in depth) on the surface of polystyrene (PS) were made by polarized Nd:YAG laser irradiation, at a wavelength of 266 nm. The influence of such "nanoscale features" on the orientation and alignment of cells and their mineralized Collagen Matrix was investigated, using rabbit mesenchymal stem cell (MSC)-derived osteoblast-like cells. The cells and actin stress fibers were aligned and elongated along the direction of the nanogrooves. In addition, the alignment of Collagen Matrix was also influenced by underlying nanogrooves. The results suggested that nanoscale fibrous cues in the longitudinal direction might contribute to the aligned formation of bone tissue. This may provide an effective approach for constructing biomimetic bone tissue. © Mary Ann Liebert, Inc.

Etsuko Fujihara - One of the best experts on this subject based on the ideXlab platform.

  • Patch Grafting Using an Ologen Collagen Matrix to Manage Tubal Exposure in Glaucoma Tube Shunt Surgery.
    Case Reports in Ophthalmology, 2018
    Co-Authors: Masaki Tanito, Ichiya Sano, Yoshifumi Ikeda, Etsuko Fujihara
    Abstract:

    To report the results using an ologen Collagen Matrix as a patch graft in eyes with tubal exposure after tube shunt surgery. Case 1 was an 82-year-old man with tubal exposure in his right eye 26 months after receiving a Baerveldt glaucoma implant. The tube was covered by surrounding conjunctival tissue combined with subconjunctival placement of an ologen Collagen Matrix as a patch graft. Two years after implantation, the tube was not exposed. Anterior-segment optical coherence tomography (AS-OCT) showed dense conjunctival tissue over the tube. Case 2 was an 82-year-old man with peripheral keratitis, anterior scleritis, and secondary glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve and cataract surgery. Intraoperatively, scleritis-related scleral thinning prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Seventeen months after implantation, the tube was not exposed. Case 3 was a 52-year-old man with diabetic maculopathy and steroid-induced glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve. Intraoperatively, a flap defect prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Three weeks postoperatively, AS-OCT showed thick subconjunctival tissue over the tube. Three months after implantation, the tube was not exposed. The ologen Collagen Matrix can be used successfully as a patch graft to prevent and treat tubal exposure after tube shunt surgery.

  • Patch Grafting Using an Ologen Collagen Matrix to Manage Tubal Exposure in Glaucoma Tube Shunt Surgery.
    Case Reports in Ophthalmology, 2018
    Co-Authors: Masaki Tanito, Ichiya Sano, Yoshifumi Ikeda, Etsuko Fujihara
    Abstract:

    Purpose: To report the results using an ologen Collagen Matrix as a patch graft in eyes with tubal exposure after tube shunt surgery. Case Reports: Case 1 was an 82-year-old man with tubal exposure in his right eye 26 months after receiving a Baerveldt glaucoma implant. The tube was covered by surrounding conjunctival tissue combined with subconjunctival placement of an ologen Collagen Matrix as a patch graft. Two years after implantation, the tube was not exposed. Anterior-segment optical coherence tomography (AS-OCT) showed dense conjunctival tissue over the tube. Case 2 was an 82-year-old man with peripheral keratitis, anterior scleritis, and secondary glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve and cataract surgery. Intraoperatively, scleritis-related scleral thinning prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Seventeen months after implantation, the tube was not exposed. Case 3 was a 52-year-old man with diabetic maculopathy and steroid-induced glaucoma in the right eye who underwent tube shunt surgery using an Ahmed glaucoma valve. Intraoperatively, a flap defect prevented the tube from being covered fully by an autologous scleral flap. An ologen Collagen Matrix was placed over the scleral flap as a patch graft. Three weeks postoperatively, AS-OCT showed thick subconjunctival tissue over the tube. Three months after implantation, the tube was not exposed. Conclusions: The ologen Collagen Matrix can be used successfully as a patch graft to prevent and treat tubal exposure after tube shunt surgery.

Karsten Wiebe - One of the best experts on this subject based on the ideXlab platform.

  • Thoracic Wall Reconstruction with Acellular Porcine Dermal Collagen Matrix
    Thoracic and Cardiovascular Surgeon, 2014
    Co-Authors: Joachim Schmidt, Bassam Redwan, Volkan Koesek, Barbara Heitplatz, Benedetta Bedetti, Hermann Aebert, Karsten Wiebe
    Abstract:

    Background  Major thoracic wall resections require the implantation of foreign materials for reconstruction and stabilization. Recently, biological Collagen Matrixes have emerged as an alternative to the routinely used synthetic materials. Materials and Methods  Retrospectively, we analyzed our initial experience of chest wall reconstruction on large defects using a cross-linked porcine dermal acellular Collagen Matrix mesh with a thickness of 1.5 mm. Results  Six sarcoma patients with a mean age of 46 (22–66) years underwent chest wall resections. Complete thoracic wall defects (mean area 149 cm 2 ) ranged from 8 × 10 to 15 × 20 cm in size. In the majority of cases, only mobilized subcutaneous tissue and skin were used for soft-tissue coverage of the implanted porcine Collagen Matrix patches. Implantation and postoperative courses were uneventful in all patients. No local infections or wound healing problems occurred. The Collagen material resulted in durable and good to excellent chest wall stability in clinical follow-ups, and on computed tomography scans spanning over 3.5 years. Histological examination showed integration, neovascularization, and long-term persistence of the Collagen Matrix on late reoperation of one patient. Conclusion  Acellular porcine dermal Collagen Matrix is a feasible and reliable biological patch material for reconstruction of the thoracic wall. Excellent wound healing and long-term stability are achieved even in large defects or complete sternal replacements.

  • Thoracic Wall Reconstruction with Acellular Porcine Dermal Collagen Matrix.
    The Thoracic and cardiovascular surgeon, 2014
    Co-Authors: Joachim Schmidt, Bassam Redwan, Volkan Koesek, Barbara Heitplatz, Benedetta Bedetti, Hermann Aebert, Karsten Wiebe
    Abstract:

     Major thoracic wall resections require the implantation of foreign materials for reconstruction and stabilization. Recently, biological Collagen Matrixes have emerged as an alternative to the routinely used synthetic materials.  Retrospectively, we analyzed our initial experience of chest wall reconstruction on large defects using a cross-linked porcine dermal acellular Collagen Matrix mesh with a thickness of 1.5 mm.  Six sarcoma patients with a mean age of 46 (22-66) years underwent chest wall resections. Complete thoracic wall defects (mean area 149 cm2) ranged from 8 × 10 to 15 × 20 cm in size. In the majority of cases, only mobilized subcutaneous tissue and skin were used for soft-tissue coverage of the implanted porcine Collagen Matrix patches. Implantation and postoperative courses were uneventful in all patients. No local infections or wound healing problems occurred. The Collagen material resulted in durable and good to excellent chest wall stability in clinical follow-ups, and on computed tomography scans spanning over 3.5 years. Histological examination showed integration, neovascularization, and long-term persistence of the Collagen Matrix on late reoperation of one patient.  Acellular porcine dermal Collagen Matrix is a feasible and reliable biological patch material for reconstruction of the thoracic wall. Excellent wound healing and long-term stability are achieved even in large defects or complete sternal replacements. Georg Thieme Verlag KG Stuttgart · New York.

Tohru Tateshita - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Collagen Matrix containing transforming growth factor (TGF)-β1 on wound contraction
    Journal of Dermatological Science, 2001
    Co-Authors: Tohru Tateshita, Fumio Kaneko
    Abstract:

    We evaluated the effectiveness of transforming growth factor (TGF)-β1 on wound contraction, both alone and in combination with Collagen Matrix, using an in vivo delayed wound healing type model. To clarify the mechanisms involved in the effectiveness of TGF-β1, we also used a fibroblast-populated Collagen gel contraction in vitro model. Although we found that TGF-β1 significantly accelerated contraction of the fibroblast-populated Collagen gel in vitro, we demonstrated that both Collagen Matrix alone and 1.0 μg of TGF-β1 alone significantly inhibited wound contraction in the in vivo model. In addition, the combination of TGF-β1 and Collagen Matrix was much more effective than TGF-β1 alone, a finding which was supported by histopathological examination. Wounds treated with Collagen Matrix containing TGF-β1 showed horizontal rearrangement of Collagen fibers in the dermal part as well as evidence of active fibroblast proliferation, which was not observed in the scar regions of controls. These results show that the application of TGF-β1 treated Collagen Matrix is effective for preventing contraction producing so called ‘neodermis’ in treating a delayed healing type model and may be highly beneficial for treating chronic wounds.

  • Effects of a Collagen Matrix containing prostaglandin E1 on wound contraction
    Journal of Dermatological Science, 2001
    Co-Authors: Li-jun Zhou, Tohru Tateshita
    Abstract:

    Abstract In this study, we evaluated the effectiveness of prostaglandin (PG) E1 in inhibiting wound contraction, both alone and in combination with Collagen Matrix, using a in vivo full thickness skin defect model. To clarify the mechanisms involved in this inhibition we also used a fibroblast-populated Collagen gel contraction in vitro model. We demonstrated that Collagen Matrix alone significantly inhibited wound contraction PG E1 alone did not. Interestingly, their combination was much more effective than either Collagen Matrix or PG E1 alone, a finding which was also supported by histopathological examination. Wounds treated with Collagen Matrix, but not control wounds, showed horizontal rearrangement of Collagen fibers in the dermal part as well as evidence of active fibroblast proliferation which was not observed in scar regions surrounded by normal dermis. With the fibroblast-populated Collagen gel contraction in vitro model, we found that PG E1 significantly inhibited contraction at a high dose. It was concluded that Collagen Matrix combined with PG E1 is effective for preventing contracture producing so called neodermis than Collagen Matrix alone, which remains one of the most challenging problems in treating full thickness type wounds.

  • Effects of a Collagen Matrix containing basic fibroblast growth factor on wound contraction.
    Journal of Biomedical Materials Research, 1999
    Co-Authors: Tohru Tateshita, Masayuki Inoue
    Abstract:

    We evaluated the effectiveness of basic fibroblast growth factor (bFGF) in inhibiting wound contraction, both alone and in combination with Collagen Matrix, using a simulated in vivo delayed healing type model. We also studied the mechanisms involved in this inhibition in in vitro experiments using fibroblast populated Collagen gels. As a result, we were able to demonstrate that both Collagen Matrix and bFGF significantly inhibited wound contraction; especially, bFGF acted in a dose-dependent fashion. Interestingly, their combination was much more effective than either Collagen Matrix or bFGF alone, a finding that was supported by the histopathological data. Wounds treated with Collagen Matrix, but not control wounds, showed horizontal rearrangement of Collagen fibers in dermis as well as evidence of fibroblast proliferation, which was not observed in scar regions surrounded by normal dermis. Using fibroblast-populated Collagen gel contraction as an in vitro model, we found that bFGF significantly inhibited contraction. Taking all these results together, it was concluded that Collagen Matrix is useful not only as a carrier of cytokines such as bFGF, but also for the quick closure of chronic wounds, thereby preventing contracture, which remains one of the most challenging problems in treating this type of wound. Application of bFGF-treated Collagen Matrix to chronic wounds such as decubitus, and diabetic and leg ulcers may prove to be highly beneficial in clinical practice. © 1999 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 48: 621–630, 1999

  • Effect of a Collagen Matrix containing epidermal growth factor on wound contraction
    Wound Repair and Regeneration, 1998
    Co-Authors: Masayuki Inoue, Tohru Tateshita, Yoshimitsu Kuroyanagi, Nobuyuki Shioya
    Abstract:

    : Excessive wound contraction is known to lead to pathological wound contracture. Using a rabbit model, we applied a bovine type I Collagen Matrix sponge as a dermal substitute and human epidermal growth factor to full-thickness excisional wounds. Wound contraction was assessed 14 and 28 days after wounding. It was found that both Collagen Matrix and epidermal growth factor significantly inhibited wound contraction (p 0.05; 36.5 +/- 2.8%, p < 0.05; and 39.8 +/- 2.1%, p < 0.001 at 1, 10, and 100 ng/ml of epidermal growth factor, respectively). In conclusion, Collagen Matrix and epidermal growth factor, particularly in combination, may be useful in the prevention of wound contracture.