Material Properties of Abdominal Aortic Aneurysm Wall From Uniaxial Tests

2000 ◽  
Author(s):  
Mano J. Thubrikar ◽  
Michel Labrosse ◽  
Jihad Al-Soudi ◽  
Brett Fowler ◽  
Francis Robicsek
Keyword(s):  
Experimental Data ◽  
Material Properties ◽  
Aortic Wall ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Modeling Tools ◽  
Aneurysm Wall ◽  
Abdominal Aortic ◽  
Abdominal Aortic Aneurysm Wall ◽  
Mechanical Models

Abstract Abdominal aortic aneurysms (AAA) rupture when the aortic wall cannot withstand the stresses and strains induced by the pulsatile blood pressure. In recent years, different mechanical models of aneurysms have been presented (Vorp et al., 1998, Di Martino et al., 1998, Thubrikar et al., 1999). Although powerful modeling tools such as finite elements are available, there is still a need for experimental data concerning the mechanical properties of the aneurysm wall.

Presence of NGAL/MMP-9 complexes in human abdominal aortic aneurysms

2007 ◽  
Vol 98 (08) ◽  
pp. 427-433 ◽  
Author(s):  
Chaoyong Zhu ◽  
Angela Silveira ◽  
Anne-Louise Hemdahl ◽  
Anders Hamsten ◽  
Ulf Hedin ◽  
...  
Keyword(s):  
Elective Surgery ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Intraluminal Thrombus ◽  
Neutrophil Gelatinase Associated Lipocalin ◽  
Reducing Conditions ◽  
Aneurysm Wall ◽  
Abdominal Aortic ◽  
Aneurysm Growth ◽  
Neutrophil Gelatinase

SummaryIt has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA enlargement and rupture.The growth of theAAA is dependent on proteolytic degradation of elastin. Here, we analysed whether the neutrophil gelatinase-associated lipocalin (NGAL) is expressed within the thrombus and the aneurysm wall. NGAL can bind to metalloproteinase- 9 (MMP-9) and inhibit its degradation,thereby preserving enzymatic activity. Biopsies were obtained from thrombus- free and thrombus-covered aneurysm wall and the intraluminal thrombus from patients undergoing elective surgery for AAA. Immunohistochemistry and real-time PCR were used to study NGAL and MMP-9 expression. Immunoprecipitation, gel zymography,Western blot and ELISA were used to detect and quantify NGAL/MMP-9 complexes. NGAL was detected in the thrombus, the interface between the thrombus and the underlying wall and in the wall itself.Double staining showed that neutrophils are the major source of NGAL expression. Immunoprecipitation of MMP-9 with antibody against NGAL showed that complexes of NGAL and active MMP-9 were present in thrombus, the interface fluid and the aneurysm wall.Western blot analyses using non-reducing conditions and gel zymography demonstrated that high-molecular-weight complexes of NGAL/MMP-9 were present within the different regions.The concentration of the NGAL/MMP-9 complex was highest in the luminal part of the thrombus. In conclusion, NGAL in complex with activated MMP-9 is present in AAA wall and thrombus. Neutrophil-derived NGAL could enhance the proteolytic activity associated with AAA, but the importance of this mechanism for aneurysm growth remains to be shown.

scholarly journals Temporal changes in mouse aortic wall gene expression during the development of elastase-induced abdominal aortic aneurysms

2006 ◽  
Vol 43 (5) ◽  
pp. 1010-1020 ◽  
Author(s):  
Sarah J. Van Vickle-Chavez ◽  
William S. Tung ◽  
Tarek S. Absi ◽  
Terri L. Ennis ◽  
Dongli Mao ◽  
...  
Keyword(s):  
Gene Expression ◽  
Aortic Wall ◽  
Abdominal Aortic Aneurysms ◽  
Temporal Changes ◽  
Aortic Aneurysms ◽  
Abdominal Aortic

scholarly journals Intraluminal Thrombus Is Associated With Aortic Wall Weakening in Small Ruptured Abdominal Aortic Aneurysms

2016 ◽  
Vol 64 (2) ◽  
pp. 543-544
Author(s):  
Jeffrey D. Crawford ◽  
Stephen J. Haller ◽  
Gregory J. Landry ◽  
Cherrie Abraham ◽  
Gregory L. Moneta ◽  
...  
Keyword(s):  
Aortic Wall ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Intraluminal Thrombus ◽  
Abdominal Aortic ◽  
Ruptured Abdominal Aortic Aneurysms

scholarly journals Finite Element Analysis of Abdominal Aortic Aneurysms: Predicted Rupture Risk Correlates With Aortic Wall Histology in Individual Patients

2014 ◽  
Vol 21 (4) ◽  
pp. 556-564 ◽  
Author(s):  
Philipp Erhart ◽  
Caspar Grond-Ginsbach ◽  
Maani Hakimi ◽  
Felix Lasitschka ◽  
Susanne Dihlmann ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Aortic Wall ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Rupture Risk ◽  
Element Analysis ◽  
Abdominal Aortic

scholarly journals Integrated Plasma and Tissue Proteomics Reveals Attractin Release by Intraluminal Thrombus of Abdominal Aortic Aneurysms and Improves Aneurysm Growth Prediction in Humans

2020 ◽  
Author(s):  
Regent Lee ◽  
Ismail Cassimee ◽  
Honglei Huang ◽  
Pierfrancesco Lapolla ◽  
Anirudh Chandrashekar ◽  
...  
Keyword(s):  
Growth Rate ◽  
Endothelial Dysfunction ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Universal Method ◽  
Plasma Samples ◽  
Growth Prediction ◽  
Aneurysm Wall ◽  
Abdominal Aortic ◽  
Increased Risk

Background: Abdominal aortic aneurysms (AAA) are pathological dilatations of the aorta which can result in rupture and mortality. Novel methods of predicting AAA growth is a recognised priority in AAA research. Patient with AAAs have increased risk of cardiovascular morbidity. We have previously observed accelerated systemic endothelial dysfunction (measured by brachial artery FMD) in AAA patients and FMD correlates with future AAA growth. Further, systemic endothelial dysfunction is reversed by AAA repair. AAAs contain intra-luminal thrombus (ILT). Since ILT is either removed or excluded from circulation after successful repair of AAAs, we hypothesise that ILT to be the source of mediators that contribute to AAA growth. Methods: Patients were prospectively recruited to the Study (Ethics Ref SC/13/0250). Plasma samples were collected at baseline and at 1 year from each patient. Plasma samples were also collected before and at 10-12 weeks after surgery from each patient (n=29). Paired aneurysm wall, ILT, omental biopsies were collected intra-operatively during open surgical repair (n=3). In addition to analyses of the tissue, supernatant was obtained from ex vivo culture of these paired tissue samples. Samples were subjected to non-targeted LC-MSMS workflow after trypsin digest, using the Universal method to discover novel proteins. LC-MSMS data was analysed using the Progenesis QI pipeline. Results: The median AAA size at baseline was 48 mm. 59 patients were prospectively followed for 12 months. The median growth rate of AAA was 3.8%/year (IQR 1.9% to 6.8%). Comparison between patients with the fastest vs the slowest (n=10 each) showed 116 proteins to be differentially expressed in their plasma. Among these proteins, 35 also changed significantly before and after AAA repair, suggesting their origin to from the AAA complex. Comparison of the proteomics profile of aneurysm tissue, ILT, and omental artery show 128 proteins to be uniquely present in ILT. Analyses of the tissue culture supernatant further revealed 3 proteins that are: (i) uniquely present in ILT; (ii) released by ILT; (iii) systemic levels reduced after AAA surgery; (iv) differs between fast and slow growth AAAs. One of these proteins is attractin. To validate the LC-MSMS data, attractin level in individual patient was measured by ELISA. Consistent with the LC-MSMS data, plasma attractin level is higher in patients with fast AAA growth. Plasma attractin level correlates significantly with future AAA growth rate (Spearman r=0.35, P<;0.005). Using attractin and AAA diameter as input variables, the AUROC for predicting no growth of AAA at 12 months is 85% (P<0.001). Conclusion: We show that ILT of AAAs releases mediators (such as attractin) during the natural history of AAA growth. These are novel biomarkers for AAA growth prediction in humans.

The Development of Physiological Compliant Abdominal Aortic Aneurysm Models for In Vitro Flow Studies

2009 ◽  
Author(s):  
Timothy J. Corbett ◽  
Barry J. Doyle ◽  
Anthony Callanan ◽  
Tim M. McGloughlin
Keyword(s):  
Abdominal Aortic Aneurysm ◽  
Aortic Aneurysm ◽  
Material Properties ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Flow Loop ◽  
The Past ◽  
Abdominal Aortic

A vast amount of experimental research has been undertaken in the past decade to investigate different aspects of preoperative and postoperative abdominal aortic aneurysms (AAAs). Much of this research has been based on the use of mock arteries in an in vitro flow loop to mimic the behaviour of the abdominal aorta in vivo [1]. These models should be reproducible, have consistent material properties, consistent thickness and be physiological in behaviour.

Neutrophil Chemotaxis and Neutrophil Elastase in the Aortic Wall in Patients with Abdominal Aortic Aneurysms

1991 ◽  
Vol 4 (4) ◽  
pp. 423-430 ◽  
Author(s):  
Jon R. Cohen ◽  
Leo Keegan ◽  
Isaac Sarfati ◽  
Debra Danna ◽  
Carl Ilardi ◽  
...  
Keyword(s):  
Neutrophil Elastase ◽  
Aortic Wall ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Neutrophil Chemotaxis ◽  
Abdominal Aortic
Sign in / Sign up

Export Citation Format

Share Document