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In JoVE (2)
- Autólogas progenitoras endoteliais Cell Technology Semear e Teste de biocompatibilidade para dispositivos Cardiovascular em Modelo Animal Grande
- Câmara de placas paralelas de fluxo e Circuito de fluxo contínuo para avaliar células progenitoras endoteliais sob estresse de cisalhamento Fluxo Laminar
Other Publications (6)
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Articles by Fu-Hsiung Lin in JoVE
JoVE Bioengineering
Autólogas progenitoras endoteliais Cell Technology Semear e Teste de biocompatibilidade para dispositivos Cardiovascular em Modelo Animal Grande
1Department of Biomedical Engineering, Duke University, 2School of Medicine, Duke University, 3Department of Surgery, Duke University Medical Center, 4School of Medicine, University of Pennsylvania
Um método para semeadura de titânio de sangue entrar em contato com biomateriais com células autólogas e biocompatibilidade teste é descrito. Este método utiliza células progenitoras endoteliais e tubos de titânio, semeadas em poucos minutos de implante cirúrgico em suínos as cavas. Esta técnica é adaptável a muitas outras implantáveis dispositivos biomédicos.
JoVE Bioengineering
Câmara de placas paralelas de fluxo e Circuito de fluxo contínuo para avaliar células progenitoras endoteliais sob estresse de cisalhamento Fluxo Laminar
1Department of Surgery, Duke University Medical Center, 2Department of Biomedical Engineering, Duke University, 3School of Medicine, University of Pennsylvania, 4Department of Medicine, Division of Cardiology, Duke University Medical Center
Estamos descrevendo um método para submeter células aderentes a tensão de cisalhamento do fluxo laminar em um circuito de fluxo contínuo estéril. Adesão das células, a morfologia pode ser estudada através da câmara transparente, amostras obtidas do circuito para análise de metabólitos e células colhidos após a exposição de cisalhamento para futuros experimentos ou cultura.
Other articles by Fu-Hsiung Lin on PubMed
Ferulic Acid Stabilizes a Solution of Vitamins C and E and Doubles Its Photoprotection of Skin
Ferulic acid is a potent ubiquitous plant antioxidant. Its incorporation into a topical solution of 15%l-ascorbic acid and 1%alpha-tocopherol improved chemical stability of the vitamins (C+E) and doubled photoprotection to solar-simulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation. Inhibition of apoptosis was associated with reduced induction of caspase-3 and caspase-7. This antioxidant formulation efficiently reduced thymine dimer formation. This combination of pure natural low molecular weight antioxidants provides meaningful synergistic protection against oxidative stress in skin and should be useful for protection against photoaging and skin cancer.
Ubiquinone, Idebenone, and Kinetin Provide Ineffective Photoprotection to Skin when Compared to a Topical Antioxidant Combination of Vitamins C and E with Ferulic Acid
Role of Mitogen-activated Protein Kinase in Osteoblast Differentiation
Local control of osteoblast differentiation and bone formation is not well understood. We have previously seen biphasic effects on cell differentiation in response to the short- and long-term exposure to IL-1β in rat calvarial osteoblasts. To characterize the signaling pathway mechanisms regulating IL-1β biphasic effects, we examined the contribution of mitogen-activated protein kinase (MAPK) family. Cells were pretreated with specific inhibitors to extracellular signal-regulated kinase (ERK, PD98059), p38 (SB203580), and c-JUN N-terminal kinase (JNK, SP600125), then co-cultured with IL-1β for 2, 4, and 6 days. Cell differentiation was determined by measuring bone nodules after 10 days of culture. These inhibitors did not alter biphasic effects of IL-1β on cell differentiation. However, PD98059 and U2016, another inhibitor of ERK activation robustly increased osteoblast differentiation compared to vehicle-treated control in a time- and dose-dependent manner. PD98059 appears to stimulate alkaline phosphatase (ALP) activity to promote cell differentiation, where IL-1β appears to suppress it. Interestingly, continuous ERK inhibition with PD98059, after 2 and 4 days of IL-1β treatment, enhanced the IL-1β anabolic effect by increasing bone nodules formed. These observations provide a potential mechanism involving ERK pathway in osteoblasts differentiation and suggest that MAPK family may not directly regulate IL-1β biphasic effects.
The Biocompatibility of Titanium Cardiovascular Devices Seeded with Autologous Blood-derived Endothelial Progenitor Cells: EPC-seeded Antithrombotic Ti Implants
Implantable and extracorporeal cardiovascular devices are commonly made from titanium (Ti) (e.g. Ti-coated Nitinol stents and mechanical circulatory assist devices). Endothelializing the blood-contacting Ti surfaces of these devices would provide them with an antithrombogenic coating that mimics the native lining of blood vessels and the heart. We evaluated the viability and adherence of peripheral blood-derived porcine endothelial progenitor cells (EPCs), seeded onto thin Ti layers on glass slides under static conditions and after exposure to fluid shear stresses. EPCs attached and grew to confluence on Ti in serum-free medium, without preadsorption of proteins. After attachment to Ti for 15 min, less than 5% of the cells detached at a shear stress of 100 dyne / cm(2). Confluent monolayers of EPCs on smooth Ti surfaces (Rq of 10 nm), exposed to 15 or 100 dyne/cm(2) for 48 h, aligned and elongated in the direction of flow and produced nitric oxide dependent on the level of shear stress. EPC-coated Ti surfaces had dramatically reduced platelet adhesion when compared to uncoated Ti surfaces. These results indicate that peripheral blood-derived EPCs adhere and function normally on Ti surfaces. Therefore EPCs may be used to seed cardiovascular devices prior to implantation to ameliorate platelet activation and thrombus formation.
Use of Autologous Blood-derived Endothelial Progenitor Cells at Point-of-care to Protect Against Implant Thrombosis in a Large Animal Model
Titanium (Ti) is commonly utilized in many cardiovascular devices, e.g. as a component of Nitinol stents, intra- and extracorporeal mechanical circulatory assist devices, but is associated with the risk of thromboemboli formation. We propose to solve this problem by lining the Ti blood-contacting surfaces with autologous peripheral blood-derived late outgrowth endothelial progenitor cells (EPCs) after having previously demonstrated that these EPCs adhere to and grow on Ti under physiological shear stresses and functionally adapt to their environment under flow conditions ex vivo. Autologous fluorescently-labeled porcine EPCs were seeded at the point-of-care in the operating room onto Ti tubes for 30 min and implanted into the pro-thrombotic environment of the inferior vena cava of swine (n = 8). After 3 days, Ti tubes were explanted, disassembled, and the blood-contacting surface was imaged. A blinded analysis found all 4 cell-seeded implants to be free of clot, whereas 4 controls without EPCs were either entirely occluded or partially thrombosed. Pre-labeled EPCs had spread and were present on all 4 cell-seeded implants while no endothelial cells were observed on control implants. These results suggest that late outgrowth autologous EPCs represent a promising source of lining Ti implants to reduce thrombosis in vivo.
