The Experts below are selected from a list of 11040 Experts worldwide ranked by ideXlab platform
J Fisher - One of the best experts on this subject based on the ideXlab platform.
-
in vitro endothelialization of biodegradable vascular grafts via endothelial progenitor cell seeding and maturation in a tubular perfusion system bioreactor
Tissue Engineering Part C-methods, 2016Co-Authors: Anthony J Melchiorri, Laura G Bracaglia, Lucas K Kimerer, Narutoshi Hibino, J FisherAbstract:A critical challenge to the success of biodegradable vascular grafts is the establishment of a Healthy Endothelium. To establish this monolayer of endothelial cells (ECs), a variety of techniques have been developed, including cell seeding. Vascular grafts may be seeded with relevant cell types and allowed to mature before implantation. Due to the low proliferative ability of adult ECs and issues with donor site morbidity, there has been increasing interest in using endothelial progenitor cells (EPCs) for vascular healing procedures. In this work, we combined the proliferative and differentiation capabilities of a commercial cell line of early EPCs with an established bioreactor system to support the maturation of cell-seeded vascular grafts. All components of the vascular graft and bioreactor setup are commercially available and allow for complete customization of the scaffold and culturing system. This bioreactor setup enables the control of flow through the graft, imparting fluid shear stress on EPCs a...
-
in vitro endothelialization of biodegradable vascular grafts via endothelial progenitor cell seeding and maturation in a tubular perfusion system bioreactor
Tissue Engineering Part C-methods, 2016Co-Authors: Anthony J Melchiorri, Laura G Bracaglia, Lucas K Kimerer, Narutoshi Hibino, J FisherAbstract:A critical challenge to the success of biodegradable vascular grafts is the establishment of a Healthy Endothelium. To establish this monolayer of endothelial cells (ECs), a variety of techniques have been developed, including cell seeding. Vascular grafts may be seeded with relevant cell types and allowed to mature before implantation. Due to the low proliferative ability of adult ECs and issues with donor site morbidity, there has been increasing interest in using endothelial progenitor cells (EPCs) for vascular healing procedures. In this work, we combined the proliferative and differentiation capabilities of a commercial cell line of early EPCs with an established bioreactor system to support the maturation of cell-seeded vascular grafts. All components of the vascular graft and bioreactor setup are commercially available and allow for complete customization of the scaffold and culturing system. This bioreactor setup enables the control of flow through the graft, imparting fluid shear stress on EPCs and affecting cellular proliferation and differentiation. Grafts cultured with EPCs in the bioreactor system demonstrated greatly increased cell populations and neotissue formation compared with grafts seeded and cultured in a static system. Increased expression of markers for mature endothelial tissues were also observed in bioreactor-cultured EPC-seeded grafts. These findings suggest the distinct advantages of a customizable bioreactor setup for the proliferation and maturation of EPCs. Such a strategy may be beneficial for utilizing EPCs in vascular tissue engineering applications.
Paula J Ousley - One of the best experts on this subject based on the ideXlab platform.
-
deep lamellar endothelial keratoplasty visual acuity astigmatism and endothelial survival in a large prospective series
Ophthalmology, 2005Co-Authors: Mark A Terry, Paula J OusleyAbstract:Purpose To report the 6-month results for the treatment of endothelial dysfunction in a large, prospective series of deep lamellar endothelial keratoplasty (DLEK) procedures. Design Prospective, noncomparative, interventional case series. Participants One hundred eyes of 88 patients with corneal edema from Fuchs' dystrophy and pseudophakia. Methods A limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. Two eyes were converted to penetrating keratoplasty (PK) at the time of DLEK surgery because of poor dissections. Of the 98 eyes that had completed DLEK surgeries, 36 eyes received a large-incision technique (9-mm scleral access incision) and 62 eyes received a small-incision technique (5-mm scleral access incision). A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue then was excised and replaced through the pocket with a similar size donor disc containing Healthy Endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary. Main Outcome Measures Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction (MR) astigmatism, and endothelial cell density (ECD) were evaluated prospectively. Results At 6 months after surgery, all 98 DLEK corneas were clear and the grafts were healed in good position. The mean BSCVA was 20/46, with a range between 20/20 and 20/400. The average MR astigmatism was 1.34±0.86 diopters (D), representing an average change in astigmatism from before surgery of +0.28±1.08 D ( P = 0.013). The average ECD at 6 months was 2140±427 cells/mm 2 , representing a mean cell loss from preoperative donor cell measurements of 25%. Conclusions The DLEK procedure, with its absence of corneal surface incisions and sutures, preserves the normal corneal topography, minimizes astigmatism, and provides a Healthy donor endothelial cell count and function. The DLEK procedure represents a reasonable alternative to PK, and compared with historical PK data, offers superior refractive outcomes in the treatment of endothelial dysfunction.
-
replacing the Endothelium without corneal surface incisions or sutures the first united states clinical series using the deep lamellar endothelial keratoplasty procedure
Ophthalmology, 2003Co-Authors: Mark A Terry, Paula J OusleyAbstract:Abstract Purpose To report the 6- and 12-month results of the first United States clinical series of deep lamellar endothelial keratoplasty (DLEK) in the treatment of endothelial dysfunction. Design Prospective, noncomparative, interventional case series. Participants Eight eyes of eight patients with corneal edema from Fuchs' dystrophy and pseudophakia. Methods A 9.0-mm limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue was then excised and replaced through the pocket with a same size donor disc containing Healthy Endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary. Main outcome measures Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction astigmatism, TMS-1 topography, ultrasonic pachymetry, Orbscan topography, and endothelial cell density were evaluated. Intraoperative and postoperative complications are reported. Results At 6 and 12 months after surgery, all eight corneas were clear and the grafts were healed in good position. At 6 months, the BSCVA varied between 20/30 and 20/70, the average change in astigmatism from before surgery was +1.13 diopters (D; ±1.50 D), the average change in corneal power was −0.4 D (±1.7 D), the average pachymetry was 648 μm (±134 μm), and the average endothelial cell count was 2290 cells/mm 2 (±372 cells/mm 2 ). At 12 months, three of the four eyes reaching this time gate were 20/40 or better, with a change in astigmatism from before surgery of only +0.81 D (± 0.55 D), a corneal power change of −1.3 D (± 0.4 D), and an endothelial density of 2409 cells/mm 2 (± 154 cells/mm 2 ). One of the original nine eyes entered into this study required conversion to standard penetrating keratoplasty as a result of a microperforation during recipient pocket dissection and has experienced no ill effects. Conclusions The DLEK procedure, with its absence of corneal surface incisions and sutures, is a safe procedure that preserves the normal corneal topography, minimizes astigmatism and corneal power changes, and provides a Healthy donor endothelial cell count and function. If interface optical clarity can be maintained, then this technique offers considerable advantages over penetrating keratoplasty in the treatment of endothelial dysfunction.
Anthony J Melchiorri - One of the best experts on this subject based on the ideXlab platform.
-
in vitro endothelialization of biodegradable vascular grafts via endothelial progenitor cell seeding and maturation in a tubular perfusion system bioreactor
Tissue Engineering Part C-methods, 2016Co-Authors: Anthony J Melchiorri, Laura G Bracaglia, Lucas K Kimerer, Narutoshi Hibino, J FisherAbstract:A critical challenge to the success of biodegradable vascular grafts is the establishment of a Healthy Endothelium. To establish this monolayer of endothelial cells (ECs), a variety of techniques have been developed, including cell seeding. Vascular grafts may be seeded with relevant cell types and allowed to mature before implantation. Due to the low proliferative ability of adult ECs and issues with donor site morbidity, there has been increasing interest in using endothelial progenitor cells (EPCs) for vascular healing procedures. In this work, we combined the proliferative and differentiation capabilities of a commercial cell line of early EPCs with an established bioreactor system to support the maturation of cell-seeded vascular grafts. All components of the vascular graft and bioreactor setup are commercially available and allow for complete customization of the scaffold and culturing system. This bioreactor setup enables the control of flow through the graft, imparting fluid shear stress on EPCs a...
-
in vitro endothelialization of biodegradable vascular grafts via endothelial progenitor cell seeding and maturation in a tubular perfusion system bioreactor
Tissue Engineering Part C-methods, 2016Co-Authors: Anthony J Melchiorri, Laura G Bracaglia, Lucas K Kimerer, Narutoshi Hibino, J FisherAbstract:A critical challenge to the success of biodegradable vascular grafts is the establishment of a Healthy Endothelium. To establish this monolayer of endothelial cells (ECs), a variety of techniques have been developed, including cell seeding. Vascular grafts may be seeded with relevant cell types and allowed to mature before implantation. Due to the low proliferative ability of adult ECs and issues with donor site morbidity, there has been increasing interest in using endothelial progenitor cells (EPCs) for vascular healing procedures. In this work, we combined the proliferative and differentiation capabilities of a commercial cell line of early EPCs with an established bioreactor system to support the maturation of cell-seeded vascular grafts. All components of the vascular graft and bioreactor setup are commercially available and allow for complete customization of the scaffold and culturing system. This bioreactor setup enables the control of flow through the graft, imparting fluid shear stress on EPCs and affecting cellular proliferation and differentiation. Grafts cultured with EPCs in the bioreactor system demonstrated greatly increased cell populations and neotissue formation compared with grafts seeded and cultured in a static system. Increased expression of markers for mature endothelial tissues were also observed in bioreactor-cultured EPC-seeded grafts. These findings suggest the distinct advantages of a customizable bioreactor setup for the proliferation and maturation of EPCs. Such a strategy may be beneficial for utilizing EPCs in vascular tissue engineering applications.
Paolo Decuzzi - One of the best experts on this subject based on the ideXlab platform.
-
deciphering the relative contribution of vascular inflammation and blood rheology in metastatic spreading
arXiv: Biological Physics, 2018Co-Authors: Hilaria Mollica, Alessandro Coclite, Marco E Miali, Rui C Pereira, Chiara Manneschi, Andrea Decensi, Laura Paleari, Paolo DecuzziAbstract:Vascular adhesion of circulating tumor cells (CTCs) is a key step in cancer spreading. If inflammation is recognized to favor the formation of vascular metastatic niches, little is known about the contribution of blood rheology to CTC deposition. Herein, a microfluidic chip, covered by a confluent monolayer of endothelial cells, is used for analyzing the adhesion and rolling of colorectal (HCT 15) and breast (MDA MB 231) cancer cells under different biophysical conditions. These include the analysis of cell transport in a physiological solution and whole blood; over a Healthy and a TNF alpha inflamed Endothelium; with a flow rate of 50 and 100 nL/min. Upon stimulation of the endothelial monolayer with TNF alpha (25 ng/mL), CTC adhesion increases by 2 to 4 times whilst cell rolling velocity only slightly reduces. Notably, whole blood also enhances cancer cell deposition by 2 to 3 times, but only on the unstimulated vasculature. For all tested conditions, no statistically significant difference is observed between the two cancer cell types. Finally, a computational model for CTC transport demonstrates that a rigid cell approximation reasonably predicts rolling velocities while cell deformability is needed to model adhesion. These results would suggest that, within microvascular networks, blood rheology and inflammation contribute similarly to CTC deposition thereby facilitating the formation of metastatic niches along the entire network, including the Healthy Endothelium. In microfluidic based assays, neglecting blood rheology would significantly underestimate the metastatic potential of cancer cells.
-
deciphering the relative contribution of vascular inflammation and blood rheology in metastatic spreading
Biomicrofluidics, 2018Co-Authors: Hilaria Mollica, Alessandro Coclite, Marco E Miali, Rui C Pereira, Chiara Manneschi, Andrea Decensi, Laura Paleari, Paolo DecuzziAbstract:Vascular adhesion of circulating tumor cells (CTCs) is a key step in cancer spreading. If inflammation is recognized to favor the formation of vascular “metastatic niches,” little is known about the contribution of blood rheology to CTC deposition. Herein, a microfluidic chip, covered by a confluent monolayer of endothelial cells, is used for analyzing the adhesion and rolling of colorectal (HCT-15) and breast (MDA-MB-231) cancer cells under different biophysical conditions. These include the analysis of cell transport in a physiological solution and whole blood over a Healthy and a TNF-α inflamed Endothelium with a flow rate of 50 and 100 nl/min. Upon stimulation of the endothelial monolayer with TNF-α (25 ng/ml), CTC adhesion increases from 2 to 4 times whilst cell rolling velocity only slightly reduces. Notably, whole blood also enhances cancer cell deposition from 2 to 3 times, but only on the unstimulated vasculature. For all tested conditions, no statistically significant difference is observed between the two cancer cell types. Finally, a computational model for CTC transport demonstrates that a rigid cell approximation reasonably predicts rolling velocities while cell deformability is needed to model adhesion. These results would suggest that, within microvascular networks, blood rheology and inflammation contribute similarly to CTC deposition, thereby facilitating the formation of metastatic niches along the entire network, including the Healthy Endothelium. In microfluidic-based assays, neglecting blood rheology would significantly underestimate the metastatic potential of cancer cells.Vascular adhesion of circulating tumor cells (CTCs) is a key step in cancer spreading. If inflammation is recognized to favor the formation of vascular “metastatic niches,” little is known about the contribution of blood rheology to CTC deposition. Herein, a microfluidic chip, covered by a confluent monolayer of endothelial cells, is used for analyzing the adhesion and rolling of colorectal (HCT-15) and breast (MDA-MB-231) cancer cells under different biophysical conditions. These include the analysis of cell transport in a physiological solution and whole blood over a Healthy and a TNF-α inflamed Endothelium with a flow rate of 50 and 100 nl/min. Upon stimulation of the endothelial monolayer with TNF-α (25 ng/ml), CTC adhesion increases from 2 to 4 times whilst cell rolling velocity only slightly reduces. Notably, whole blood also enhances cancer cell deposition from 2 to 3 times, but only on the unstimulated vasculature. For all tested conditions, no statistically significant difference is observed betw...
Mark A Terry - One of the best experts on this subject based on the ideXlab platform.
-
deep lamellar endothelial keratoplasty visual acuity astigmatism and endothelial survival in a large prospective series
Ophthalmology, 2005Co-Authors: Mark A Terry, Paula J OusleyAbstract:Purpose To report the 6-month results for the treatment of endothelial dysfunction in a large, prospective series of deep lamellar endothelial keratoplasty (DLEK) procedures. Design Prospective, noncomparative, interventional case series. Participants One hundred eyes of 88 patients with corneal edema from Fuchs' dystrophy and pseudophakia. Methods A limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. Two eyes were converted to penetrating keratoplasty (PK) at the time of DLEK surgery because of poor dissections. Of the 98 eyes that had completed DLEK surgeries, 36 eyes received a large-incision technique (9-mm scleral access incision) and 62 eyes received a small-incision technique (5-mm scleral access incision). A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue then was excised and replaced through the pocket with a similar size donor disc containing Healthy Endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary. Main Outcome Measures Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction (MR) astigmatism, and endothelial cell density (ECD) were evaluated prospectively. Results At 6 months after surgery, all 98 DLEK corneas were clear and the grafts were healed in good position. The mean BSCVA was 20/46, with a range between 20/20 and 20/400. The average MR astigmatism was 1.34±0.86 diopters (D), representing an average change in astigmatism from before surgery of +0.28±1.08 D ( P = 0.013). The average ECD at 6 months was 2140±427 cells/mm 2 , representing a mean cell loss from preoperative donor cell measurements of 25%. Conclusions The DLEK procedure, with its absence of corneal surface incisions and sutures, preserves the normal corneal topography, minimizes astigmatism, and provides a Healthy donor endothelial cell count and function. The DLEK procedure represents a reasonable alternative to PK, and compared with historical PK data, offers superior refractive outcomes in the treatment of endothelial dysfunction.
-
replacing the Endothelium without corneal surface incisions or sutures the first united states clinical series using the deep lamellar endothelial keratoplasty procedure
Ophthalmology, 2003Co-Authors: Mark A Terry, Paula J OusleyAbstract:Abstract Purpose To report the 6- and 12-month results of the first United States clinical series of deep lamellar endothelial keratoplasty (DLEK) in the treatment of endothelial dysfunction. Design Prospective, noncomparative, interventional case series. Participants Eight eyes of eight patients with corneal edema from Fuchs' dystrophy and pseudophakia. Methods A 9.0-mm limbal, scleral, partial-depth incision provided access for a deep lamellar corneal pocket dissection. A 7.5- to 8.0-mm posterior lamellar disc of recipient tissue was then excised and replaced through the pocket with a same size donor disc containing Healthy Endothelium. A temporary air bubble in the anterior chamber was used for donor tissue adherence, and no surface corneal incisions or sutures were necessary. Main outcome measures Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction astigmatism, TMS-1 topography, ultrasonic pachymetry, Orbscan topography, and endothelial cell density were evaluated. Intraoperative and postoperative complications are reported. Results At 6 and 12 months after surgery, all eight corneas were clear and the grafts were healed in good position. At 6 months, the BSCVA varied between 20/30 and 20/70, the average change in astigmatism from before surgery was +1.13 diopters (D; ±1.50 D), the average change in corneal power was −0.4 D (±1.7 D), the average pachymetry was 648 μm (±134 μm), and the average endothelial cell count was 2290 cells/mm 2 (±372 cells/mm 2 ). At 12 months, three of the four eyes reaching this time gate were 20/40 or better, with a change in astigmatism from before surgery of only +0.81 D (± 0.55 D), a corneal power change of −1.3 D (± 0.4 D), and an endothelial density of 2409 cells/mm 2 (± 154 cells/mm 2 ). One of the original nine eyes entered into this study required conversion to standard penetrating keratoplasty as a result of a microperforation during recipient pocket dissection and has experienced no ill effects. Conclusions The DLEK procedure, with its absence of corneal surface incisions and sutures, is a safe procedure that preserves the normal corneal topography, minimizes astigmatism and corneal power changes, and provides a Healthy donor endothelial cell count and function. If interface optical clarity can be maintained, then this technique offers considerable advantages over penetrating keratoplasty in the treatment of endothelial dysfunction.
