An in vitro rotation model composed of disposables for investigation of endothelialization of artificial vascular prostheses

SummaryTissue plasminogen activator labeled with radioactive iodine (125I-tPA) was immobilized on vascular prostheses chemically modified with a thin coating of water-insoluble surfactant, tridodecylmethylammonium chloride (TDM AC). Surfactant- treated Dacron, polytetrafluoroethylene (PTFE), silastic, polyethylene and polyurethane bound appreciable amounts of 125I- tPA (5-30 μg 125I-tPA/cm2). Upon exposure to human plasma, the amount of 125I-tPA bound to the surface shows an initial drop during the first hour of incubation, followed by a slower, roughly exponential release with a t½ of appoximately 75 hours. Prostheses containing bound tPA show fibrinolytic activity as measured both by lysis of clots formed in vitro, and by hydrolysis of a synthetic polypeptide substrate. Prior to incubation in plasma, tPA bound to a polymer surface has an enzymic activity similar, if not identical to that of the native enzyme in buffered solution. However, exposure to plasma causes a decrease in the fibrinolytic activity of both bound tPA and enzyme released from the surface of the polymer. These data demonstrate that surfactant-treated prostheses can bind tPA, and that these chemically modified devices can act as a slow-release drug delivery system with the potential for reducing prosthesis-induced thromboembolism.

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The Influence of a Knitted Hydrophilic Prosthesis of Blood Vessels on the Activation of Coagulation System—In Vitro Study

Nanomaterials ◽

10.3390/nano11061600 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1600

Author(s):

Maria Szymonowicz ◽

Maciej Dobrzynski ◽

Sara Targonska ◽

Agnieszka Rusak ◽

Zbigniew Rybak ◽

...

Keyword(s):

Blood Vessels ◽

Initial Period ◽

In Vitro Study ◽

Vascular Prosthesis ◽

Coagulation System ◽

Factor Xii ◽

Scanning Calorimetry ◽

Vascular Prostheses ◽

Control Value

The replacement of affected blood vessels of the polymer material can cause imbalances in the blood haemostatic system. Changes in blood after the implantation of vascular grafts depend not only on the chemical composition but also on the degree of surface wettability. The Dallon® H unsealed hydrophilic knitted vascular prosthesis double velour was assessed at work and compare with hydrophobic vascular prosthesis Dallon®. Spectrophotometric studies were performed in the infrared and differential scanning calorimetry, which confirmed the effectiveness of the process of modifying vascular prostheses. Determination of the parameters of coagulation time of blood after contact in vitro with Dallon® H vascular prosthesis was also carried out. Prolongation of activated thromboplastin time, decreased activity of factor XII, IX and VIII, were observed. The prolonged thrombin and fibrinogen were reduced in the initial period of the experiment. The activity of plasminogen and antithrombin III and protein C were at the level of control value. The observed changes in the values of determined parameters blood coagulation do not exceed the range of referential values for those indexes. The observed changes are the result of considerable blood absorptiveness by the prosthesis of blood vessels and their sealing.

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Attenuation of Flow Disturbances in Tapered Arterial Grafts

Journal of Biomechanical Engineering ◽

10.1115/1.3168383 ◽

1989 ◽

Vol 111 (4) ◽

pp. 303-310 ◽

Cited By ~ 15

Author(s):

R. A. Black ◽

T. V. How

Keyword(s):

Pulsatile Flow ◽

Reynolds Numbers ◽

Axial Distance ◽

Pulsed Ultrasound ◽

Arterial Grafts ◽

Vascular Prostheses ◽

Disturbance Intensity ◽

Flow Disturbances ◽

Percent Area

Flow disturbances in tapered arterial grafts of angles of taper between 0.5 and 1.0 deg were measured in vitro using a pulsed ultrasound Doppler velocimeter. The increase in transition Reynolds numbers with angle of taper and axial distance was determined for steady flow. The instantaneous centerline velocities were measured distal to a 50 percent area stenosis (as a model of a proximal anastomosis), in steady and pulsatile flow, from which the disturbance intensities were calculated. A significant reduction in post-stenotic disturbance intensity was recorded in the tapered grafts, relative to a conventional cylindrical graft. In pulsatile flow with a large backflow component, however, there was an increase in disturbance intensity due to diverging flow during flow reversal. This was observed only in the 1.0 deg tapered graft. These findings indicate that taper is an important consideration in the design of vascular prostheses.

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Ciprofloxacin loaded vascular prostheses functionalized with poly-methylbeta- cyclodextrin: The importance of in vitro release conditions

Journal of Drug Delivery Science and Technology ◽

10.1016/j.jddst.2019.101166 ◽

2019 ◽

Vol 53 ◽

pp. 101166 ◽

Cited By ~ 1

Author(s):

M.J. Garcia-Fernandez ◽

M. Maton ◽

Y. Benzine ◽

N. Tabary ◽

E. Jean Baptiste ◽

...

Keyword(s):

In Vitro Release ◽

Vascular Prostheses ◽

Vitro Release

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Limitations of In-Vitro Labeling of Endothelial Cells with Indium-111 Oxine

Cell Transplantation ◽

10.1177/096368979500400307 ◽

1995 ◽

Vol 4 (3) ◽

pp. 291-296 ◽

Cited By ~ 6

Author(s):

H.M.H. Carr ◽

J.V. Smyth ◽

O.B. Rooney ◽

P.D. Dodd ◽

H. Sharma ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Cell Attachment ◽

Control Group ◽

Vascular Prostheses ◽

Long Term Effect ◽

Indium 111 ◽

Suitable Technique

Indium-111 oxine labeling is widely used as a marker of endothelial cell attachment to vascular prostheses. The long term effect of labeling human adult endothelial cells (HAECs) with this isotope has not been determined. In this study the viability of labeled HAECs, leakage of isotope from labeled cells and adherence of circulating isotope to fibronectin coated prostheses were investigated over 24 h. The effect of incubation time on labeling efficiency was also assessed. There were significant differences in cell viability between the labeled and unlabeled groups beyond 4 h (p < 0.005, 2-tailed, unpaired t-test). In the control group cell numbers increased by 42% while in the labeled group this had decreased by 20% at 24 h. Spontaneous leakage increased with time but was maximal in the first 2 h. Adherence of circulating isotope to fibronectin coated expanded polytetrafluoroethylene (ePTFE) grafts was minimal but was significantly greater to gelatin impregnated Dacron (GEL-SEAL) beyond 1 hour (p < 0.05). Incubation times greater than 5 minutes during labeling do not significantly improve labeling efficiency, and may contribute to toxicity by prolonging exposure to oxine. Indium-111 oxine labeling of HAECs is a suitable technique for acute studies of endothelial cell kinetics up to 4 h, but its use in chronic studies may lead to significant underestimations of cell retention.

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In Vitro C5a Generation by Synthetic Vascular Prostheses: Implications for Graft Incorporation in Vivo

Biomaterials Medical Devices and Artificial Organs ◽

10.3109/10731198609117546 ◽

1986 ◽

Vol 14 (3-4) ◽

pp. 249-255 ◽

Cited By ~ 1

Author(s):

Rakesh Sindhi

Keyword(s):

Vascular Prostheses ◽

Graft Incorporation

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Mesothelial Cell Adherence to Vascular Prostheses and Their Subsequent Growth In Vitro

Cell Transplantation ◽

10.1177/096368979400300107 ◽

1994 ◽

Vol 3 (1) ◽

pp. 41-48 ◽

Cited By ~ 3

Author(s):

Apollo Pronk ◽

Arthur A.G.M. Hoynck Van Papendrecht ◽

Piet Leguit ◽

Henri A. Verbrugh ◽

Roel P.A.J. Verkooyen ◽

...

Keyword(s):

Endothelial Cells ◽

Cell Attachment ◽

Mesothelial Cell ◽

Mesothelial Cells ◽

Subsequent Growth ◽

Vascular Prostheses ◽

Peritoneal Mesothelial Cells ◽

Viable Cells ◽

Human Peritoneal Mesothelial Cells

Cell seeding may decrease the thrombogenicity of implanted vascular grafts, but its application is hampered by the limited availability of autologous endothelial cells. Human peritoneal mesothelial cells have blood flow supporting qualities and are readily available. This study investigated the adherence of mesothelial cells to vascular prostheses and their subsequent growth in vitro. Circular pieces of various vascular prosthetic materials were seeded with 51Chromium-labeled mesothelial and endothelial cells and left for either 5, 15, 30, 60, and 120 minutes. The unattached cells were removed and the degree of cell attachment was measured. The number of mesothelial cells to Dacron increased during the first 60 min up to 35.2 % of the seeded inoculum whereafter a plateau was reached. Scanning electron microscopy showed spreaded mesothelial cells adherent to the Dacron fibers. A significant increase in adherence was observed after preincubation of Dacron with 10 μg/mL fibronectin, but no improvement was found after preincubation with human serum albumin or gelatin. Mesothelial cells adhered better to Gelcoated than to Gelsealed or plain Dacron. The adherence of mesothelial cells to ePTFE (Teflon) was significantly poorer. No significant differences in adherence were found between mesothelial and endothelial cells. Mesothelial cell growth on Dacron resulted in a modest increase in the number of viable cells during 27 days, which implies biocompatibility of Dacron and mesothelial cells in vitro.

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In Vitro Fatigue Properties of Prototype Woven Vascular Prosthesis with Poly (trimethylene terephthalate) Filaments as Circumferential Yarns

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501200700416 ◽

2012 ◽

Vol 7 (4) ◽

pp. 155892501200700

Author(s):

Ying Chen ◽

Xin Ding ◽

Yuling Li ◽

Xueqian Zhao

Keyword(s):

Fatigue Testing ◽

Fatigue Behavior ◽

Vascular Prosthesis ◽

Fatigue Properties ◽

Vascular Prostheses ◽

Initial Modulus ◽

Before And After ◽

Show Evidence ◽

Improve Compliance

As far as we know, fatigue properties of woven vascular prosthesis with PTT filaments as circumferential yarns which could improve compliance due to their lower initial modulus and better elasticity had not yet studied. In this study viscoelastic properties of PTT filaments were studied and fatigue properties of woven vascular prostheses with PTT filaments as circumferential yarns were tested using an accelerated fatigue tester. The changes of each property before and after the fatigue testing show evidence of fatigue. It will be more evidence of fatigue with increasing fatigue cycles and PTT tubular samples show better fatigue behavior compared to PET tubular samples.

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