Search results for "Bioprosthesis"
showing 10 items of 14 documents
The pre-vascularisation of a collagen-chondroitin sulphate scaffold using human amniotic fluid-derived stem cells to enhance and stabilise endothelia…
2015
Abstract A major problem in tissue engineering (TE) is graft failure in vivo due to core degradation in in vitro engineered constructs designed to regenerate thick tissues such as bone. The integration of constructs post-implantation relies on the rapid formation of functional vasculature. A recent approach to overcome core degradation focuses on the creation of cell-based, pre-engineered vasculature formed within the TE construct in vitro , prior to implantation in vivo . The primary objective of this study was to investigate whether an amniotic fluid-derived stem cell (AFSC)–human umbilical vein endothelial cell (HUVEC) co-culture could be used to engineer in vitro vasculature in a collag…
Decellularized tracheal prelamination implant: A proposed bilateral double organ technique
2021
Introduction In tracheal replacement transplantation, prelamination is a critical stage. Nowadays, the most widely used prelamination technique is the prethoracic fascia flap with lateral thoracic artery. We propose a flap based on the internal thoracic artery, which allows a relatively non-aggressive double organ implant, and we have tested its efficacy in decellularized tracheas. Material and methods Tracheas of albino New Zealand rabbits were decellularized following a protocol that uses detergents and cryogenization, sterilized with 1kGy gamma radiation and tutorized with a stent. Bilateral pedicled flaps made of pectoral fascia and a muscular component were harvested through a longitud…
Bovine pericardium for duraplasty: clinical results in 32 patients.
2001
Bovine pericardium has been widely used for grafts in cardiac surgery and seems to have suitable properties for use as a dural graft. We report on the use of solvent-preserved, gamma-sterilized Tutoplast bovine pericardium for dural grafts in 32 patients undergoing cranial and spinal operations with the objective of clinically assessing this material and technique by a retrospective analysis. All available records were reviewed and information regarding the indication for grafting, complications, and outcome were collected and analyzed for all patients. Indications for grafting included tethered cord myelolysis, closure of lumbosacral myeloceles, Chiari decompression, posterior fossa cranio…
Value and limitations of transesophageal echocardiography in the evaluation of aortic prostheses.
1993
Results of 34 transesophageal (TEE) studies in patients with suspected aortic prosthetic dysfunction were compared with transthoracic echocardiographic (TTE) results and to anatomic findings. Mass lesions noted at surgery (autopsy) were correctly described in 93% by TEE versus 43% by TTE. Abscesses were detected in 88% by TEE versus 18% by TTE. Bioprosthetic degeneration was visualized in 88% versus 38% and prosthetic obstruction correctly identified in 75% versus 50% by TEE and TTE, respectively. Anatomic aortic regurgitant lesions were identified in 96% by TEE versus 77% by TTE, whereas the correct origin was detected in 88% of cases by TEE versus 54% of cases by TTE. TEE provides valuabl…
Evaluation of the stromal vascular fraction of adipose tissue as the basis for a stem cell-based tissue-engineered vascular graft
2017
Abstract Objective One of the rate-limiting barriers within the field of vascular tissue engineering is the lengthy fabrication time associated with expanding appropriate cell types in culture. One particularly attractive cell type for this purpose is the adipose-derived mesenchymal stem cell (AD-MSC), which is abundant and easily harvested from liposuction procedures. Even this cell type has its drawbacks, however, including the required culture period for expansion, which could pose risks of cellular transformation or contamination. Eliminating culture entirely would be ideal to avoid these concerns. In this study, we used the raw population of cells obtained after digestion of human lipo…
Infrapopliteal Composite Bypass with Autologous Vein and Second Generation Glutaraldehyde Stabilized Human Umbilical Vein (HUV) for Critical Lower Li…
2007
Objective. To audit a single center consecutive series of infrapopliteal composite bypasses with second generation glutaraldehyde stabilized human umbilical vein. Design. Retrospective study. Patients. From January 1996 to July 2006 89 femoro-distal bypasses were constructed in 85 patients with HUV and residual vein segments as composite grafts in the absence of sufficient length of autologous vein. Methods. All patients with infrainguinal bypass operations were registered prospectively. Bypasses to infrapopliteal arteries performed with HUV-composite grafts were reviewed for graft patency, limb salvage, patient survival and possible biodegeneration of the HUV. Results. Early graft thrombos…
Impact of T-cell-mediated immune response on xenogeneic heart valve transplantation: short-term success and mid-term failure.
2017
Objectives Allogeneic frozen cryopreserved heart valves (allografts or homografts) are commonly used in clinical practice. A major obstacle for their application is the limited availability in particular for paediatrics. Allogeneic large animal studies revealed that alternative ice-free cryopreservation (IFC) results in better matrix preservation and reduced immunogenicity. The objective of this study was to evaluate xenogeneic (porcine) compared with allogeneic (ovine) IFC heart valves in a large animal study. Methods IFC xenografts and allografts were transplanted in 12 juvenile merino sheep for 1-12 weeks. Immunohistochemistry, ex vivo computed tomography scans and transforming growth fa…
In Vivo Functional Evaluation of Tissue-Engineered Vascular Grafts Fabricated Using Human Adipose-Derived Stem Cells from High Cardiovascular Risk Po…
2016
Many preclinical evaluations of autologous small-diameter tissue-engineered vascular grafts (TEVGs) utilize cells from healthy humans or animals. However, these models hold minimal relevance for clinical translation, as the main targeted demographic is patients at high cardiovascular risk such as individuals with diabetes mellitus or the elderly. Stem cells such as adipose-derived mesenchymal stem cells (AD-MSCs) represent a clinically ideal cell type for TEVGs, as these can be easily and plentifully harvested and offer regenerative potential. To understand whether AD-MSCs sourced from diabetic and elderly donors are as effective as those from young nondiabetics (i.e., healthy) in the conte…
Sequential Femorodistal Composite Bypass with Second Generation Glutaraldehyde Stabilized Human Umbilical Vein (HUV)
2005
Abstract Objective To evaluate the performance of sequential composite bypasses with second generation glutaraldehyde stabilized human umbilical vein (HUV) and autologous vein. Design Retrospective study of consecutive patients, in a single centre. Patients From January 1998 to December 2003, 54 femoro-distal HUV-autologous vein sequential composite bypasses were constructed in 52 patients with critical leg ischemia and absence of sufficient length of autologous vein. Methods All infra-inguinal bypass operations were registered in a computerized database and prospectively followed. Bypasses using sequential HUV-composite technique were reviewed for graft patency, limb salvage and patient su…
Outcomes of complex femorodistal sequential autologous vein and biologic prosthesis composite bypass grafts
2014
Objective Femorodistal autologous vein bypass proves to be the preferred surgical therapy for long arterial occlusions and provides excellent early and long-term results in critical lower limb ischemia. Whenever vein length was insufficient and two distal outflow arteries were present, a sequential composite bypass configuration was chosen with human umbilical vein (HUV) or ovine collagen prosthesis (Omniflow II; Bio Nova International Pty Ltd, North Melbourne, Australia) as the proximal prosthetic part of the bypass. Single-center experience with this technique regarding limb salvage, graft function, secondary reinterventions, and biodegeneration is presented. Methods Between January 1998 …