Article
Biophysics
Alexis Throop, Martina Bukac, Rana Zakerzadeh
Summary: This study investigates the biomechanical role of intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA). The results demonstrate that while ILT can reduce wall stress, it significantly decreases oxygen transport within the tissue, leading to wall hypoxia.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2022)
Article
Environmental Sciences
Emil Marian Arbanasi, Adrian Vasile Muresan, Catalin Mircea Cosarca, Eliza Mihaela Arbanasi, Raluca Niculescu, Septimiu Toader Voidazan, Adrian Dumitru Ivanescu, Ioana Halmaciu, Rarel Cristian Filep, Lucian Marginean, Shuko Suzuki, Traian Chirila, Reka Kaller, Eliza Russu
Summary: Computed tomography angiography can accurately predict the risk of abdominal aortic aneurysm rupture. High baseline values of imaging markers and underlying risk factors such as hypertension, ischemic heart disease, and atrial fibrillation are associated with AAA rupture.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2022)
Article
Biotechnology & Applied Microbiology
Burton Carbino, Alexander Guy, Michael Durka, Rana Zakerzadeh
Summary: The objective of this study is to analyze the impact of intraluminal thrombus (ILT) presence and morphology on oxygen transport in abdominal aortic aneurysms (AAA). The study found that ILT reduces oxygen flux to the arterial wall, creating an inflammatory environment and decreasing its strength. The geometry of ILT was also found to potentially affect AAA rupture. ILT thickness and length were found to be the parameters that most significantly influence decreased oxygen flow and concentration values, while thick thrombi exacerbate hypoxic conditions in the arterial wall. Conversely, arterial wall oxygen concentration was nearly independent of the AAA bulge diameter.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Article
Cardiac & Cardiovascular Systems
Aykut Can Arslan, Huseyin Enes Salman
Summary: Abdominal aortic aneurysm (AAA) is a serious health condition characterized by the enlargement of the abdominal aorta beyond its normal diameter. The risk of rupture in AAA can be determined using computational techniques such as computational fluid dynamics (CFD) and fluid-structure interaction (FSI). This study investigates the effect of intraluminal thrombus (ILT) and arterial material properties on the mechanical stresses in AAA using CFD simulations and FSI analysis.
JOURNAL OF CARDIOVASCULAR DEVELOPMENT AND DISEASE
(2023)
Article
Chemistry, Multidisciplinary
Mohammed Almijalli
Summary: This research utilized computer modeling to study the impact of intraluminal thrombus (ILT) on abdominal aortic aneurysm (AAA) rupture, and found that ILT does not lead to local hypoxia as previously theorized.
APPLIED SCIENCES-BASEL
(2021)
Article
Surgery
Arjet Helena Margaretha Nievergeld, Esther Jorien Maas, Joerik de Ruijter, Judith Helena Cornelia Fonken, Marcus Rodolph Henricus Maria van Sambeekan, Richard Godfried Paulus Lopata
Summary: This study proposed a semi-automatic segmentation method for abdominal aortic aneurysms and their intraluminal thrombus based on 3D ultrasound, and validated the results with computed tomography. The study found strong correlations between vessel and lumen distensibility with blood pressure, and also a correlation between lumen distensibility and ILT thickness.
EUROPEAN JOURNAL OF VASCULAR AND ENDOVASCULAR SURGERY
(2023)
Article
Surgery
I. Koncar, D. Nikolic, Z. Milosevic, N. Bogavac-Stanojevic, N. Ilic, M. Dragas, M. Sladojevic, M. Markovic, A. Vujcic, N. Filipovic, L. Davidovic
Summary: This study aimed to compare anatomical and biomechanical features between elective and ruptured abdominal aortic aneurysms (AAAs). Clinical, anatomical, and biomechanical data of 98 AAA patients were collected and analyzed. The study found that maximal aneurysm diameter, relative intraluminal thrombus, and total aneurysm volume were important predictors of AAA rupture, and biomechanical parameters had high predictive value.
FRONTIERS IN SURGERY
(2023)
Article
Clinical Neurology
Sandrine Morel, Agnieszka Karol, Vanessa Graf, Graziano Pelli, Henning Richter, Esther Sutter, Vincent Braunersreuther, Juhana Frosen, Philippe Bijlenga, Brenda R. Kwak, Katja M. Nuss
Summary: The study revealed sex-dependent differences in aneurysm growth and intraluminal thrombus resolution. While processes like endothelial cell coverage and collagen deposition appear to have a strong hormonal dependence, wall inflammation and aneurysm growth seem to be influenced by both hormones and parent artery size.
JOURNAL OF NEUROSURGERY
(2021)
Article
Geriatrics & Gerontology
Yuehong Liu, Sijie Li, Ye Wu, Fang Wu, Ying Chang, Haibin Li, Xiuqin Jia, Luca Saba, Xunming Ji, Qi Yang
Summary: This study showed that 3D-VWMRI has high sensitivity and specificity for identifying thrombus in patients with CCAD, and the presence of intraluminal thrombus on 3D-VWMRI is strongly associated with territorial ischemic stroke.
Article
Chemistry, Multidisciplinary
Yongjie Jiao, Chaojing Li, Shaojie Li, Xingxing Liu, Shuang Yu, Xiaofeng Liu, Yan Li, Fujun Wang, Jianxiong Tang, Lu Wang
Summary: A fabric hydrogel composite hernia mesh with biomechanical and mesh-tissue interface dual compliance is designed for scarless abdominal wall reconstruction. The mesh is composed of a polyester knitted fabric and chitosan-polyacrylamide hydrogel complex. The adhesive fabric hydrogel composite hernia mesh offers significant clinical values for repairing abdominal wall defects and provides design ideas for repairing other load-bearing soft tissues.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Engineering, Chemical
Harry Ngwangwa, Fulufhelo Nemavhola, Thanyani Pandelani, Makhosasana Msibi, Israel Mabuda, Neil Davies, Thomas Franz
Summary: This study evaluates the passive mechanical property differences in the three main walls of the rat heart based on biaxial tensile test data. The findings suggest that there are variations in the mechanical properties of different ventricle walls, including differences in the toe region strain range, strain energy storage, and anisotropy. These findings emphasize the importance of considering wall-specific material parameters to accurately model ventricular mechanics.
Article
Engineering, Multidisciplinary
Jie-min Zhan, Tian-dong Lu, Zhi-yun Yang, Wen-qing Hu, Wei Su
Summary: This study conducted numerical simulations and experiments on patient-specific normal abdominal aorta and abdominal aortic aneurysm (AAA) models with intraluminal thrombus (ILT), which were reconstructed from CT angiography (CTA) images published online. The distribution of wall shear stress (WSS), oscillatory shear index (OSI), and relative residence time (RRT) were compared between the normal abdominal aorta and AAA under rest and exercise conditions. The results indicated that ILT deposition positions were associated with low WSS, high OSI, and high RRT regions, and the distribution of AAA wall parameters correlated with nearby vortex structures and influenced ILT formation and development. Additionally, high WSS, low OSI, and low RRT regions in the middle and lower aneurysm walls under exercise condition reduced the risk of ILT formation and development.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2022)
Article
Surgery
Milos Sladojevic, Igor Koncar, Petar Zlatanovic, Zeljka Stanojevic, David Matejevic, Sasenka Vidicevic Novakovic, Jelena Tasic, Perica Mutavdzic, Ivan Tomic, Aleksandra Isakovic, Lazar Davidovic
Summary: The study found a significant correlation between ILT volume and the largest AAA diameter, but no statistical significance in relation to proteolytic activity and protein content of the vascular wall. However, a positive correlation was found between ILT and catalase activity in the AAA wall. Future studies are needed to investigate the impact of ILT on aneurysm progression.
ANNALS OF VASCULAR SURGERY
(2022)
Article
Construction & Building Technology
Giuseppe D'Arenzo, Werner Seim, Marinella Fossetti
Summary: This study characterized the mechanical behavior of a new shear-tension connector for wall-to-floor connections of CLT structures through experimentation. The experimental results confirmed the biaxial mechanical behavior of the connector, with circular domains found for force, displacement, stiffness, and ductility parameters.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Pan Shi, Yao Chen, Ye Wei, Jian Feng, Tong Guo, Yongming Tu, Pooya Sareh
Summary: A fractal-cut graphene kirigami with rotating triangular units is proposed to overcome the brittleness limitation of existing graphene kirigami. Molecular dynamics simulations show that this configured graphene kirigami exhibits significantly improved stretchability and ductility under both uniaxial and biaxial tension, which are attributed to the deformation mechanisms of incision rotation and flipping as well as ligament tearing.
Article
Biophysics
Alireza Jafarinia, Gian Marco Melito, Thomas Stephan Mueller, Malte Rolf-Pissarczyk, Gerhard A. A. Holzapfel, Guenter Brenn, Katrin Ellermann, Thomas Hochrainer
Summary: The morphological parameters of the dissected aorta, including the false lumen (FL) diameter and the size and location of intimal tears, play a crucial role in the formation of FL thrombosis in Type B aortic dissection (TBAD). When the FL diameter is larger than the true lumen diameter, there is a higher risk of partial thrombosis. Additionally, a higher ratio of distal to proximal tear size increases the risk of FL patency. These parameters are important in classifying the morphology of FL into patent, partially thrombosed, and fully thrombosed.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Iva Brcic, Andrea Maria Kluba, Theresa Marie Godschachner, Christoph Suppan, Peter Regitnig, Nadia Dandachi, Sigurd Friedwald Lax, Marija Balic
Summary: Male breast cancer (MBC) is rare and usually presents as a locally advanced disease. Stromal tumor-infiltrating lymphocytes (sTILs) are associated with a better response to neoadjuvant chemotherapy and improved prognosis in female breast cancer, but their role in MBC is less clear. This study examined the expression of sTILs, PD-L1, and pan-TRK in MBC.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Engineering, Biomedical
Emmanouil Agrafiotis, Christian Mayer, Martin Grabenwoeger, Daniel Zimpfer, Peter Regitnig, Heinrich Maechler, Gerhard A. Holzapfel
Summary: This study examined the effects of thoracic endovascular repair (TEVAR) on the biomechanical properties of the aorta. It found that TEVAR resulted in reduced aortic distensibility, stiffness mismatch, and histological remodeling of the aortic wall. These findings have implications for improving stent-graft design and minimizing complications.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Biomedical
Anna Pukaluk, Heimo Wolinski, Christian Viertler, Peter Regitnig, Gerhard A. Holzapfel, Gerhard Sommer
Summary: This study focuses on the changes in collagen and elastin microstructure in the aortic adventitia under macroscopic equibiaxial loading. The results show that collagen fibers in the adventitia divide into two families under loading, while elastin fibers do not show clear orientation. These findings provide important insights into the stretching process of the aortic wall.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Multidisciplinary
Kevin Linka, Adrian Buganza Tepole, Gerhard A. Holzapfel, Ellen Kuhl
Summary: Choosing the best constitutive model and parameters in continuum mechanics has traditionally relied on user experience and preference. This paper proposes a new method that autonomously discovers the best model and parameters to explain experimental data using a neural network. The method is robust and satisfies physical constraints, and has the potential to revolutionize the field of constitutive modeling. Evaluation: 8 points
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Will Zhang, Javiera Jilberto, Gerhard Sommer, Michael S. Sacks, Gerhard A. Holzapfel, David A. Nordsletten
Summary: Biomechanics is important in diagnosing and treating heart conditions. Computational models can provide personalized treatment options but require accurate constitutive equations for biomechanical behavior prediction. A fractional viscoelastic modeling approach that accurately captures the viscoelastic response of the human myocardium was previously developed. This approach has comparable computational costs and only requires two additional material parameters. In this study, the implementation of this approach in Finite Element Analysis was presented, numerical properties were examined, and the physiological implications were explored.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Oncology
Balint Cserni, Darren Kilmartin, Mark O'Loughlin, Xavier Andreu, Zsuzsanna Bago-Horvath, Simonetta Bianchi, Ewa Chmielik, Paulo Figueiredo, Giuseppe Floris, Maria Pia Foschini, Aniko Kovacs, Paivi Heikkila, Janina Kulka, Anne-Vibeke Laenkholm, Inta Liepniece-Karele, Caterina Marchio, Elena Provenzano, Peter Regitnig, Angelika Reiner, Ales Ryska, Anna Sapino, Elisabeth Specht Stovgaard, Cecily Quinn, Vasiliki Zolota, Mark Webber, Sharon A. Glynn, Rita Bori, Erika Csorgo, Orsolya Olah-Nemeth, Tamas Pancsa, Anita Sejben, Istvan Sejben, Andras Voros, Tamas Zombori, Tibor Nyari, Grace Callagy, Gabor Cserni
Summary: Tumour-infiltrating lymphocytes (TILs) reflect the host's response against tumours, especially in triple-negative breast cancers. ONEST helps in estimating the number of observers required for a more reliable estimation of inter-observer agreement in TIL assessments, which has not been explored previously. This analysis suggests that between six and nine pathologists can provide a good approximation of inter-observer agreement in TIL assessments.
Article
Biotechnology & Applied Microbiology
Manuel P. Kainz, Alexander Greiner, Jan Hinrichsen, Dagmar Kolb, Ester Comellas, Paul Steinmann, Silvia Budday, Michele Terzano, Gerhard A. Holzapfel
Summary: A novel nonlinear poro-viscoelastic computational model based on the Theory of Porous Media was proposed to describe the mechanical response of brain tissue. Indentation experiments were conducted on a tailor-made hydrogel mimicking brain tissue, and an inverse parameter identification scheme was used to extract the optimal constitutive model parameters. The model was validated through finite element simulations.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Review
Cardiac & Cardiovascular Systems
Colton J. Ross, Arshid Mir, Harold M. Burkhart, Gerhard A. Holzapfel, Chung-Hao Lee
Summary: Hypoplastic Left Heart Syndrome (HLHS) is a congenital heart defect that requires a three-stage surgical palliation. Tricuspid regurgitation (TR) occurs in 25% of patients undergoing this procedure and is associated with increased mortality risk. Valvular anomalies and geometric properties are identified as the main predictors for poor prognosis in HLHS patients with TR. Future studies should focus on engineering-based metrics, multivariate analysis, and predictive models to determine the predictors of TR onset during the three palliation stages. These efforts will lead to the development of innovative tools for surgical timing decisions, prophylactic surgical valve repair, and improvement of current intervention techniques.
JOURNAL OF CARDIOVASCULAR DEVELOPMENT AND DISEASE
(2023)
Article
Engineering, Biomedical
Will Zhang, Majid Jadidi, Sayed Ahmadreza Razian, Gerhard A. Holzapfel, Alexey Kamenskiy, David A. Nordsletten
Summary: This study introduces a new viscoelastic constitutive model for the human femoropopliteal artery, which accurately describes its mechanical characteristics and time-dependent behavior. The model improves the accuracy of computational simulations and expands our knowledge of arterial mechanophysiology.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Biomedical
Federica Cosentino, Selda Sherifova, Gerhard Sommer, Giuseppe Raffa, Michele Pilato, Salvatore Pasta, Gerhard A. Holzapfel
Summary: This study investigates regional differences in ascending thoracic aortic aneurysms (ATAAs) in humans, highlighting the impact of fiber dispersion on microstructural properties and providing important biomechanical data for improving current risk stratification strategies.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Biomedical
Mohammad Javad Sadeghinia, Hans Martin Aguilera, Stig Urheim, Robert Matongo Persson, Vegard Skalstad Ellensen, Rune Haaverstad, Gerhard A. Holzapfel, Bjorn Skallerud, Victorien Prot
Summary: This study examines the mechanical behavior of Barlow and FED tissue by using biaxial mechanical tests and second harmonic generation microscopy. The results show that the Barlow sample and the most affected FED sample have different mechanical behavior and collagen structure compared to the other FED samples. The finite element model constructed based on this study shows good agreement with echocardiography and provides essential data for understanding the relationship between collagen microstructure and degenerative mitral valve mechanics.
ACTA BIOMATERIALIA
(2023)
Article
Materials Science, Multidisciplinary
Maximilian P. Wollner, Michele Terzano, Malte Rolf-Pissarczyk, Gerhard A. Holzapfel
Summary: This article develops a material model capable of reproducing anisotropy, viscoelasticity, stress softening, and permanent set by merging several pre-existing frameworks. Each constitutive effect is discussed separately in terms of its thermodynamics and mechanical interpretation and successively built on top of each other. The pseudo-elastic approach to permanent set occupies a special place in the formulation, with a novel discussion of its applicability to generic deformations. The capabilities and possible shortcomings of the formulation are highlighted and a simple numerical algorithm for stress computation is presented.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Multidisciplinary Sciences
Misael Dalbosco, Michele Terzano, Thiago A. Carniel, Eduardo A. Fancello, Gerhard A. Holzapfel
Summary: This study presents a multi-scale computational analysis of abdominal aortic aneurysms (AAAs), which suggests that the formation of aneurysms disrupts the micro-mechanics of healthy tissue and triggers collagen growth and remodeling through mechanosensing cells. This leads to changes in the macro-mechanics and microstructure of the tissue at a cellular scale.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2023)
Article
Multidisciplinary Sciences
Michele Terzano, Maximilian P. Wollner, Manuel P. Kainz, Malte Rolf-Pissarczyk, Nils Gotzen, Gerhard A. Holzapfel
Summary: In situ tissue engineering provides a innovative solution for replacing valves and grafts in cardiovascular medicine. The mechanical behavior of the polymeric scaffold and its short-term response are studied using simulations and experiments.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2023)
