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Williamson PN, Docherty PD, Jermy M, Steven BM. Literature Survey for In-Vivo Reynolds and Womersley Numbers of Various Arteries and Implications for Compliant In-Vitro Modelling. Cardiovasc Eng Technol 2024; 15:418-430. [PMID: 38499933 PMCID: PMC11319390 DOI: 10.1007/s13239-024-00723-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 02/19/2024] [Indexed: 03/20/2024]
Abstract
PURPOSE In-vitro modelling can be used to investigate haemodynamics of arterial geometry and stent implants. However, in-vitro model fidelity relies on precise matching of in-vivo conditions. In pulsatile flow, velocity distribution and wall shear stress depend on compliance, and the Reynolds and Womersley numbers. However, matching such values may lead to unachievable tolerances in phantom fabrication. METHODS Published Reynolds and Womersley numbers for 14 major arteries in the human body were determined via a literature search. Preference was given to in-vivo publications but in-vitro and in-silico values were presented when in-vivo values were not found. Subsequently ascending aorta and carotid artery case studies were presented to highlight the limitations dynamic matching would apply to phantom fabrication. RESULTS Seven studies reported the in-vivo Reynolds and Womersley numbers for the aorta and two for the carotid artery. However, only one study each reported in-vivo numbers for the remaining ten arteries. No in-vivo data could be found for the femoral, superior mesenteric and renal arteries. Thus, information derived in-vitro and in-silico were provided instead. The ascending aorta and carotid artery models required scaling to 1.5× and 3× life-scale, respectively, to achieve dimensional tolerance restrictions. Modelling the ascending aorta with the comparatively high viscosity water/glycerine solution will lead to high pump power demands. However, all the working fluids considered could be dynamically matched with low pump demand for the carotid model. CONCLUSION This paper compiles available human haemodynamic information, and highlights the paucity of information for some arteries. It also provides a method for optimal in-vitro experimental configuration.
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Affiliation(s)
- P N Williamson
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
| | - P D Docherty
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand.
- Institute of Technical Medicine, Furtwangen University, Campus Villingen-Schwenningen, Jakob-Kienzle Strasse 17, 78054, Villingen-Schwenningen, Germany.
| | - M Jermy
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
| | - B M Steven
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
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2
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Martier A, Chen Z, Schaps H, Mondrinos MJ, Fang JS. Capturing physiological hemodynamic flow and mechanosensitive cell signaling in vessel-on-a-chip platforms. Front Physiol 2024; 15:1425618. [PMID: 39135710 PMCID: PMC11317428 DOI: 10.3389/fphys.2024.1425618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Accepted: 07/10/2024] [Indexed: 08/15/2024] Open
Abstract
Recent advances in organ chip (or, "organ-on-a-chip") technologies and microphysiological systems (MPS) have enabled in vitro investigation of endothelial cell function in biomimetic three-dimensional environments under controlled fluid flow conditions. Many current organ chip models include a vascular compartment; however, the design and implementation of these vessel-on-a-chip components varies, with consequently varied impact on their ability to capture and reproduce hemodynamic flow and associated mechanosensitive signaling that regulates key characteristics of healthy, intact vasculature. In this review, we introduce organ chip and vessel-on-a-chip technology in the context of existing in vitro and in vivo vascular models. We then briefly discuss the importance of mechanosensitive signaling for vascular development and function, with focus on the major mechanosensitive signaling pathways involved. Next, we summarize recent advances in MPS and organ chips with an integrated vascular component, with an emphasis on comparing both the biomimicry and adaptability of the diverse approaches used for supporting and integrating intravascular flow. We review current data showing how intravascular flow and fluid shear stress impacts vessel development and function in MPS platforms and relate this to existing work in cell culture and animal models. Lastly, we highlight new insights obtained from MPS and organ chip models of mechanosensitive signaling in endothelial cells, and how this contributes to a deeper understanding of vessel growth and function in vivo. We expect this review will be of broad interest to vascular biologists, physiologists, and cardiovascular physicians as an introduction to organ chip platforms that can serve as viable model systems for investigating mechanosensitive signaling and other aspects of vascular physiology.
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Affiliation(s)
- A. Martier
- Department of Biomedical Engineering, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - Z. Chen
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - H. Schaps
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - M. J. Mondrinos
- Department of Biomedical Engineering, School of Science and Engineering, Tulane University, New Orleans, LA, United States
- Department of Physiology, School of Medicine, Tulane University, New Orleans, LA, United States
| | - J. S. Fang
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
- Department of Physiology, School of Medicine, Tulane University, New Orleans, LA, United States
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3
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Padmanaban P, van Galen D, Salehi-Nik N, Zakharova M, Segerink L, Rouwkema J. Switching to external flows: perturbations of developing vasculature within chicken chorioallantoic membrane. LAB ON A CHIP 2024; 24:3233-3242. [PMID: 38835278 PMCID: PMC11198391 DOI: 10.1039/d4lc00311j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/04/2024] [Indexed: 06/06/2024]
Abstract
The impact of fluid flow shear stresses, generated by the movement of blood through vasculature, on the organization and maturation of vessels is widely recognized. Nevertheless, it remains uncertain whether external fluid flows outside of the vasculature in the surrounding tissue can similarly play a role in governing these processes. In this research, we introduce an innovative technique called superfusion-induced vascular steering (SIVS). SIVS involves the controlled imposition of external fluid flow patterns onto the vascularized chick chorioallantoic membrane (CAM), allowing us to observe how this impacts the organization of vascular networks. To investigate the concept of SIVS, we conducted superfusion experiments on the intact chick CAM cultured within an engineered eggshell system, using phosphate buffered saline (PBS). To capture and analyze the effects of superfusion, we employed a custom-built microscopy setup, enabling us to image both superfused and non-superfused regions within the developing CAM. This study provides valuable insights into the practical application of fluid superfusion within an in vivo context, shedding light on its significance for understanding tissue development and manipulation in an engineering setting.
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Affiliation(s)
- Prasanna Padmanaban
- Vascularization Lab, Department of Biomechanical Engineering, Technical Medical Center, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.
| | - Danny van Galen
- Vascularization Lab, Department of Biomechanical Engineering, Technical Medical Center, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.
| | - Nasim Salehi-Nik
- Vascularization Lab, Department of Biomechanical Engineering, Technical Medical Center, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.
| | - Mariia Zakharova
- BIOS Lab on Chip group, MESA+ Institute for Nanotechnology, Technical Medical Center, Max Planck Institute for Complex Fluid Dynamics, University of Twente, Enschede, The Netherlands
| | - Loes Segerink
- BIOS Lab on Chip group, MESA+ Institute for Nanotechnology, Technical Medical Center, Max Planck Institute for Complex Fluid Dynamics, University of Twente, Enschede, The Netherlands
| | - Jeroen Rouwkema
- Vascularization Lab, Department of Biomechanical Engineering, Technical Medical Center, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.
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4
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Simonsen JB. Lipid nanoparticle-based strategies for extrahepatic delivery of nucleic acid therapies - challenges and opportunities. J Control Release 2024; 370:763-772. [PMID: 38621638 DOI: 10.1016/j.jconrel.2024.04.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/17/2024]
Abstract
The advent of lipid nanoparticles (LNPs) containing ionizable cationic lipids has enabled the encapsulation, stabilization, and intracellular delivery of nucleic acid payloads, leading to FDA-approved siRNA-based therapy and mRNA-based vaccines. Other nucleic acid-based therapeutic modalities, including protein replacement and CRISPR-mediated gene knockout and editing, are being tested in clinical trials, in many cases, for the treatment of liver-related diseases. However, to fully exploit these therapies beyond the liver, improvements in their delivery to extrahepatic targets are needed. Towards this end, both active targeting strategies based on targeting ligands grafted onto LNPs and passive targeting relying on physicochemical LNP parameters such as surface composition, charge, and size are being evaluated. Often, the latter strategy depends on the interaction of LNPs with blood components, forming what is known as the biomolecular corona. Here, I discuss potential challenges related to current LNP-based targeting strategies and the studies of the biomolecular corona on LNPs. I propose potential solutions to overcome some of these obstacles and present approaches currently being tested in preclinical and clinical studies, which face fewer biological barriers than traditional organ-targeting approaches.
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Raviol J, Plet G, Hasegawa R, Yu K, Kosukegawa H, Ohta M, Magoariec H, Pailler-Mattei C. Towards the mechanical characterisation of unruptured intracranial aneurysms: Numerical modelling of interactions between a deformation device and the aneurysm wall. J Mech Behav Biomed Mater 2024; 153:106469. [PMID: 38402693 DOI: 10.1016/j.jmbbm.2024.106469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/13/2024] [Accepted: 02/15/2024] [Indexed: 02/27/2024]
Abstract
Intracranial aneurysm is a critical pathology related to the arterial wall deterioration. This work is an essential aspect of a large scale project aimed at providing clinicians with a non-invasive patient-specific decision support tool regarding the rupture risk assessment. A machine learning algorithm links the aneurysm shape observed and a database of UIA clinical images associated with in vivo wall mechanical properties and rupture characterisation. The database constitution is derived from a device prototype coupled with medical imaging. It provides the mechanical characterisation of the aneurysm from the wall deformation obtained by inverse analysis based on the variation of luminal volume. Before performing in vivo tests of the device on small animals, a numerical model was built to quantify the device's impact on the aneurysm wall under natural blood flow conditions. As the clinician will never be able to precisely situate the device, several locations were considered. In preparation for the inverse analysis procedure, artery material laws of increasing complexity were studied (linear elastic, hyper elastic Fung-like). Considering all the device locations and material laws, the device induced relative displacements to the Systole peak (worst case scenario with the highest mechanical stimulus linked to the blood flow) ranging from 375 μm to 1.28 mm. The variation of luminal volume associated with the displacements was between 0.95 % and 4.3 % compared to the initial Systole volume of the aneurysm. Significant increase of the relative displacements and volume variations were found with the study of different cardiac cycle moments between the blood flow alone and the device application. For forthcoming animal model studies, Spectral Photon CT Counting, with a minimum spatial resolution of 250 μm, was selected as the clinical imaging technique. Based on this preliminary study, the displacements and associated volume variations (baseline for inverse analyse), should be observable and exploitable.
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Affiliation(s)
- J Raviol
- Laboratoire de Tribologie et Dynamique des Systèmes, CNRS UMR 5513, Université de Lyon, École Centrale de Lyon, France
| | - G Plet
- Laboratoire de Tribologie et Dynamique des Systèmes, CNRS UMR 5513, Université de Lyon, École Centrale de Lyon, France
| | - R Hasegawa
- Graduate School of Engineering, Tohuku University, 980-8579, Sendai Miyagi, Japan; Institute of Fluid Science, Tohuku University, 980-8577, Sendai Miyagi, Japan
| | - K Yu
- Institute of Fluid Science, Tohuku University, 980-8577, Sendai Miyagi, Japan
| | - H Kosukegawa
- Institute of Fluid Science, Tohuku University, 980-8577, Sendai Miyagi, Japan
| | - M Ohta
- Institute of Fluid Science, Tohuku University, 980-8577, Sendai Miyagi, Japan; ElyT MaX, CNRS UMI 3537, Université de Lyon, Tohoku University, France, Japan
| | - H Magoariec
- Laboratoire de Tribologie et Dynamique des Systèmes, CNRS UMR 5513, Université de Lyon, École Centrale de Lyon, France
| | - C Pailler-Mattei
- Laboratoire de Tribologie et Dynamique des Systèmes, CNRS UMR 5513, Université de Lyon, École Centrale de Lyon, France; ISPB-Faculté de Pharmacie, Université Claude Bernard Lyon 1, Université de Lyon, France.
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6
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Pajic-Lijakovic I, Milivojevic M, McClintock PVE. Role of viscoelasticity in the appearance of low-Reynolds turbulence: considerations for modelling. J Biol Eng 2024; 18:24. [PMID: 38589891 DOI: 10.1186/s13036-024-00415-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 02/24/2024] [Indexed: 04/10/2024] Open
Abstract
Inertial effects caused by perturbations of dynamical equilibrium during the flow of soft matter constitute a hallmark of turbulence. Such perturbations are attributable to an imbalance between energy storage and energy dissipation. During the flow of Newtonian fluids, kinetic energy can be both stored and dissipated, while the flow of viscoelastic soft matter systems, such as polymer fluids, induces the accumulation of both kinetic and elastic energies. The accumulation of elastic energy causes local stiffening of stretched polymer chains, which can destabilise the flow. Migrating multicellular systems are hugely complex and are capable of self-regulating their viscoelasticity and mechanical stress generation, as well as controlling their energy storage and energy dissipation. Since the flow perturbation of viscoelastic systems is caused by the inhomogeneous accumulation of elastic energy, rather than of kinetic energy, turbulence can occur at low Reynolds numbers.This theoretical review is focused on clarifying the role of viscoelasticity in the appearance of low-Reynolds turbulence. Three types of system are considered and compared: (1) high-Reynolds turbulent flow of Newtonian fluids, (2) low and moderate-Reynolds flow of polymer solutions, and (3) migration of epithelial collectives, discussed in terms of two model systems. The models considered involve the fusion of two epithelial aggregates, and the free expansion of epithelial monolayers on a substrate matrix.
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Affiliation(s)
- Ivana Pajic-Lijakovic
- Faculty of Technology and Metallurgy, Department of Chemical Engineering, University of Belgrade, Belgrade, Serbia.
| | - Milan Milivojevic
- Faculty of Technology and Metallurgy, Department of Chemical Engineering, University of Belgrade, Belgrade, Serbia
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7
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Raviol J, Plet G, Langlois JB, Si-Mohamed S, Magoariec H, Pailler-Mattei C. In vivo mechanical characterization of arterial wall using an inverse analysis procedure: application on an animal model of intracranial aneurysm. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231936. [PMID: 38633347 PMCID: PMC11022001 DOI: 10.1098/rsos.231936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/19/2024] [Accepted: 02/24/2024] [Indexed: 04/19/2024]
Abstract
Intracranial aneurysm is a pathology related to the deterioration of the arterial wall. This work is an essential part of a large-scale project aimed at providing clinicians with a non-invasive patient-specific decision support tool to facilitate the rupture risk assessment. It will lean on the link between the aneurysm shape clinically observed and a database derived from the in vivo mechanical characterization of aneurysms. To supply this database, a deformation device prototype of the arterial wall was developed. Its use coupled with medical imaging (spectral photon-counting computed tomography providing a spatial resolution down to 250 μm) is used to determine the in vivo mechanical properties of the wall based on the inverse analysis of the quantification of the wall deformation observed experimentally. This study presents the in vivo application of this original procedure to an animal model of aneurysm. The mechanical properties of the aneurysm wall identified were consistent with the literature, and the errors between the numerical and experimental results were less than 10%. Based on these parameters, this study allows the assessment of the aneurysm stress state for a known solicitation and points towards the definition of a rupture criterion.
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Affiliation(s)
- J. Raviol
- Ecole Centrale de Lyon, CNRS, ENTPE, LTDS, UMR 5513, Écully69130, France
| | - G. Plet
- Ecole Centrale de Lyon, CNRS, ENTPE, LTDS, UMR 5513, Écully69130, France
| | | | - S. Si-Mohamed
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F69621, Villeurbanne69100, France
- Département de Radiologie, Hôpital Louis Pradel, Hospices Civils de Lyon, Bron69677, France
| | - H. Magoariec
- Ecole Centrale de Lyon, CNRS, ENTPE, LTDS, UMR 5513, Écully69130, France
| | - C. Pailler-Mattei
- Ecole Centrale de Lyon, CNRS, ENTPE, LTDS, UMR 5513, Écully69130, France
- Université de Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, Lyon69008, France
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8
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Lo SCY, McCullough JWS, Xue X, Coveney PV. Uncertainty quantification of the impact of peripheral arterial disease on abdominal aortic aneurysms in blood flow simulations. J R Soc Interface 2024; 21:20230656. [PMID: 38593843 PMCID: PMC11003782 DOI: 10.1098/rsif.2023.0656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/05/2024] [Indexed: 04/11/2024] Open
Abstract
Peripheral arterial disease (PAD) and abdominal aortic aneurysms (AAAs) often coexist and pose significant risks of mortality, yet their mutual interactions remain largely unexplored. Here, we introduce a fluid mechanics model designed to simulate the haemodynamic impact of PAD on AAA-associated risk factors. Our focus lies on quantifying the uncertainty inherent in controlling the flow rates within PAD-affected vessels and predicting AAA risk factors derived from wall shear stress. We perform a sensitivity analysis on nine critical model parameters through simulations of three-dimensional blood flow within a comprehensive arterial geometry. Our results show effective control of the flow rates using two-element Windkessel models, although specific outlets need attention. Quantities of interest like endothelial cell activation potential (ECAP) and relative residence time are instructive for identifying high-risk regions, with ECAP showing greater reliability and adaptability. Our analysis reveals that the uncertainty in the quantities of interest is 187% of that of the input parameters. Notably, parameters governing the amplitude and frequency of the inlet velocity exert the strongest influence on the risk factors' variability and warrant precise determination. This study forms the foundation for patient-specific simulations involving PAD and AAAs which should ultimately improve patient outcomes and reduce associated mortality rates.
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Affiliation(s)
- Sharp C. Y. Lo
- Centre for Computational Science, University College London, London, UK
| | | | - Xiao Xue
- Centre for Computational Science, University College London, London, UK
| | - Peter V. Coveney
- Centre for Computational Science, University College London, London, UK
- Advanced Research Computing Centre, University College London, London, UK
- Informatics Institute, Faculty of Science, University of Amsterdam, Amsterdam, The Netherlands
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9
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Manchester EL, Pirola S, Pirola S, Mastroiacovo G, Polvani G, Pontone G, Xu XY. Aortic valve neocuspidization and bioprosthetic valves: Evaluating turbulence haemodynamics. Comput Biol Med 2024; 171:108123. [PMID: 38354498 DOI: 10.1016/j.compbiomed.2024.108123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 01/05/2024] [Accepted: 02/04/2024] [Indexed: 02/16/2024]
Abstract
Aortic valve disease is often treated with bioprosthetic valves. An alternative treatment is aortic valve neocuspidization which is a relatively new reparative procedure whereby the three aortic cusps are replaced with patient pericardium or bovine tissues. Recent research indicates that aortic blood flow is disturbed, and turbulence effects have yet to be evaluated in either bioprosthetic or aortic valve neocuspidization valve types in patient-specific settings. The aim of this study is to better understand turbulence production in the aorta and evaluate its effects on laminar and turbulent wall shear stress. Four patients with aortic valve disease were treated with either bioprosthetic valves (n=2) or aortic valve neocuspidization valvular repair (n=2). Aortic geometries were segmented from magnetic resonance images (MRI), and 4D flow MRI was used to derive physiological inlet and outlet boundary conditions. Pulsatile large-eddy simulations were performed to capture the full range of laminar, transitional and turbulence characteristics in the aorta. Turbulence was produced in all aortas with highest levels occurring during systolic deceleration. In the ascending aorta, turbulence production is attributed to a combination of valvular skew, valvular eccentricity, and ascending aortic dilation. In the proximal descending thoracic aorta, turbulence production is dependent on the type of arch-descending aorta connection (e.g., a narrowing or sharp bend) which induces flow separation. Laminar and turbulent wall shear stresses are of similar magnitude throughout late systolic deceleration and diastole, although turbulent wall shear stress magnitudes exceed laminar wall shear stresses between 27.3% and 61.1% of the cardiac cycle. This emphasises the significance of including turbulent wall shear stress to improve our comprehension of progressive arterial wall diseases. The findings of this study recommend that aortic valve treatments should prioritise minimising valvular eccentricity and skew in order to mitigate turbulence generation.
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Affiliation(s)
- Emily Louise Manchester
- Department of Chemical Engineering, Imperial College London, London, United Kingdom; Department of Fluids and Environment, The University of Manchester, Manchester, United Kingdom.
| | - Selene Pirola
- Department of Chemical Engineering, Imperial College London, London, United Kingdom; Department of BioMechanical Engineering, Delft University of Technology, Delft, Netherlands.
| | - Sergio Pirola
- Department of Cardiovascular Surgery, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Giorgio Mastroiacovo
- Department of Cardiovascular Surgery, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Gianluca Polvani
- Department of Cardiovascular Surgery, Centro Cardiologico Monzino IRCCS, Milan, Italy; Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Gianluca Pontone
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy; Department of Perioperative Cardiology and Cardiovascular Imaging, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom.
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de Azevedo FS, Almeida GDC, Alvares de Azevedo B, Ibanez Aguilar IF, Azevedo BN, Teixeira PS, Camargo GC, Correia MG, Nieckele AO, Oliveira GMM. Stress Load and Ascending Aortic Aneurysms: An Observational, Longitudinal, Single-Center Study Using Computational Fluid Dynamics. Bioengineering (Basel) 2024; 11:204. [PMID: 38534478 DOI: 10.3390/bioengineering11030204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 02/05/2024] [Accepted: 02/15/2024] [Indexed: 03/28/2024] Open
Abstract
Ascending aortic aneurysm (AAoA) is a silent disease with high mortality; however, the factors associated with a worse prognosis are not completely understood. The objective of this observational, longitudinal, single-center study was to identify the hemodynamic patterns and their influence on AAoA growth using computational fluid dynamics (CFD), focusing on the effects of geometrical variations on aortic hemodynamics. Personalized anatomic models were obtained from angiotomography scans of 30 patients in two different years (with intervals of one to three years between them), of which 16 (53%) showed aneurysm growth (defined as an increase in the ascending aorta volume by 5% or more). Numerically determined velocity and pressure fields were compared with the outcome of aneurysm growth. Through a statistical analysis, hemodynamic characteristics were found to be associated with aneurysm growth: average and maximum high pressure (superior to 100 Pa); average and maximum high wall shear stress (superior to 7 Pa) combined with high pressure (>100 Pa); and stress load over time (maximum pressure multiplied by the time interval between the exams). This study provides insights into a worse prognosis of this serious disease and may collaborate for the expansion of knowledge about mechanobiology in the progression of AAoA.
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Affiliation(s)
- Fabiula Schwartz de Azevedo
- Department of Cardiology, Federal University of Rio de Janeiro, Rio de Janeiro 21941-913, RJ, Brazil
- Research and Teaching Department, Instituto Nacional de Cardiologia, Rio de Janeiro 22240-006, RJ, Brazil
| | - Gabriela de Castro Almeida
- Department of Mechanical Engineering, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-900, RJ, Brazil
| | - Bruno Alvares de Azevedo
- Department of Mechanical Engineering, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-900, RJ, Brazil
| | - Ivan Fernney Ibanez Aguilar
- Department of Mechanical Engineering, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-900, RJ, Brazil
| | - Bruno Nieckele Azevedo
- Department of Mechanical Engineering, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-900, RJ, Brazil
| | | | - Gabriel Cordeiro Camargo
- Research and Teaching Department, Instituto Nacional de Cardiologia, Rio de Janeiro 22240-006, RJ, Brazil
| | - Marcelo Goulart Correia
- Research and Teaching Department, Instituto Nacional de Cardiologia, Rio de Janeiro 22240-006, RJ, Brazil
| | - Angela Ourivio Nieckele
- Department of Mechanical Engineering, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-900, RJ, Brazil
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Manescu (Paltanea) V, Paltanea G, Antoniac A, Gruionu LG, Robu A, Vasilescu M, Laptoiu SA, Bita AI, Popa GM, Cocosila AL, Silviu V, Porumb A. Mechanical and Computational Fluid Dynamic Models for Magnesium-Based Implants. MATERIALS (BASEL, SWITZERLAND) 2024; 17:830. [PMID: 38399081 PMCID: PMC10890492 DOI: 10.3390/ma17040830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 01/26/2024] [Accepted: 02/03/2024] [Indexed: 02/25/2024]
Abstract
Today, mechanical properties and fluid flow dynamic analysis are considered to be two of the most important steps in implant design for bone tissue engineering. The mechanical behavior is characterized by Young's modulus, which must have a value close to that of the human bone, while from the fluid dynamics point of view, the implant permeability and wall shear stress are two parameters directly linked to cell growth, adhesion, and proliferation. In this study, we proposed two simple geometries with a three-dimensional pore network dedicated to a manufacturing route based on a titanium wire waving procedure used as an intermediary step for Mg-based implant fabrication. Implant deformation under different static loads, von Mises stresses, and safety factors were investigated using finite element analysis. The implant permeability was computed based on Darcy's law following computational fluid dynamic simulations and, based on the pressure drop, was numerically estimated. It was concluded that both models exhibited a permeability close to the human trabecular bone and reduced wall shear stresses within the biological range. As a general finding, the proposed geometries could be useful in orthopedics for bone defect treatment based on numerical analyses because they mimic the trabecular bone properties.
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Affiliation(s)
- Veronica Manescu (Paltanea)
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
- Faculty of Electrical Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania;
| | - Gheorghe Paltanea
- Faculty of Electrical Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania;
| | - Aurora Antoniac
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
| | - Lucian Gheorghe Gruionu
- Faculty of Mechanics, University of Craiova, 13 Alexandru Ioan Cuza, RO-200585 Craiova, Romania;
| | - Alina Robu
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
| | - Marius Vasilescu
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
| | - Stefan Alexandru Laptoiu
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
| | - Ana Iulia Bita
- Faculty of Material Science and Engineering, National University of Science and Technology Politehnica Bucharest, 313 Splaiul Independentei, District 6, RO-060042 Bucharest, Romania; (V.M.); (A.R.); (M.V.); (S.A.L.)
| | - Georgiana Maria Popa
- Department of Surgical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 10 P-ta 1 December Street, RO-410073 Oradea, Romania; (G.M.P.); (A.L.C.); (V.S.)
| | - Andreea Liliana Cocosila
- Department of Surgical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 10 P-ta 1 December Street, RO-410073 Oradea, Romania; (G.M.P.); (A.L.C.); (V.S.)
| | - Vlad Silviu
- Department of Surgical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 10 P-ta 1 December Street, RO-410073 Oradea, Romania; (G.M.P.); (A.L.C.); (V.S.)
| | - Anca Porumb
- Department of Dental Medicine, Faculty of Medicine and Pharmacy, University of Oradea, 10 P-ta 1 December Street, RO-410073 Oradea, Romania;
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12
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Messmore M, Kassab AJ, Prather RO, Arceo DAC, DeCampli W. Cilia and Nodal Flow in Asymmetry: An Engineering Perspective. Crit Rev Biomed Eng 2024; 52:63-82. [PMID: 38523441 DOI: 10.1615/critrevbiomedeng.2024051678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Over the past several years, cilia in the primitive node have become recognized more and more for their contribution to development, and more specifically, for their role in axis determination. Although many of the mechanisms behind their influence remain undocumented, it is known that their presence and motion in the primitive node of developing embryos is the determinant of the left-right axis. Studies on cilial mechanics and nodal fluid dynamics have provided clues as to how this asymmetry mechanism works, and more importantly, have shown that direct manipulation of the flow field in the node can directly influence physiology. Although relatively uncommon, cilial disorders have been shown to have a variety of impacts on individuals from chronic respiratory infections to infertility, as well as situs inversus which is linked to congenital heart disease. After first providing background information pertinent to understanding nodal flow and information on why this discussion is important, this paper aims to give a review of the history of nodal cilia investigations, an overview of cilia mechanics and nodal flow dynamics, as well as a review of research studies current and past that sought to understand the mechanisms behind nodal cilia's involvement in symmetry-breaking pathways through a biomedical engineering perspective. This discussion has the additional intention to compile interdisciplinary knowledge on asymmetry and development such that it may encourage more collaborative efforts between the sciences on this topic, as well as provide insight on potential paths forward in the field.
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Affiliation(s)
| | - Alain J Kassab
- Department of Mechanical and Aerospace Engineering, University of Central Florida, 4000 Central Florida Blvd, Orlando, Florida, USA
| | - Ray O Prather
- Embry-Riddle Aeronautical University, Daytona Beach, FL, 32114, USA; University of Central Florida, Orlando, FL 32816, USA; The Heart Center at Orlando Health Arnold Palmer Hospital for Children, Orlando, FL 32806, USA
| | - David A Castillo Arceo
- College of Engineering and Computer Science (CECS), University of Central Florida, Orlando, FL, USA
| | - William DeCampli
- University of Central Florida, Orlando, FL, 32816, USA; The Heart Center, Arnold Palmer Hospital for Children, Orlando, FL, 32806, USA
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13
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Kotlyarov S. Identification of Important Genes Associated with the Development of Atherosclerosis. Curr Gene Ther 2024; 24:29-45. [PMID: 36999180 DOI: 10.2174/1566523223666230330091241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 12/06/2022] [Accepted: 01/26/2023] [Indexed: 04/01/2023]
Abstract
Atherosclerosis is one of the most important medical problems due to its prevalence and significant contribution to the structure of temporary and permanent disability and mortality. Atherosclerosis is a complex chain of events occurring in the vascular wall over many years. Disorders of lipid metabolism, inflammation, and impaired hemodynamics are important mechanisms of atherogenesis. A growing body of evidence strengthens the understanding of the role of genetic and epigenetic factors in individual predisposition and development of atherosclerosis and its clinical outcomes. In addition, hemodynamic changes, lipid metabolism abnormalities, and inflammation are closely related and have many overlapping links in regulation. A better study of these mechanisms may improve the quality of diagnosis and management of such patients.
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Affiliation(s)
- Stanislav Kotlyarov
- Department of Nursing, Ryazan State Medical University Named After Academician I.P. Pavlov, Russian Federation
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Tscheuschner L, Tzafriri AR. Cardiovascular Tissue Engineering Models for Atherosclerosis Treatment Development. Bioengineering (Basel) 2023; 10:1373. [PMID: 38135964 PMCID: PMC10740643 DOI: 10.3390/bioengineering10121373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 11/25/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023] Open
Abstract
In the early years of tissue engineering, scientists focused on the generation of healthy-like tissues and organs to replace diseased tissue areas with the aim of filling the gap between organ demands and actual organ donations. Over time, the realization has set in that there is an additional large unmet need for suitable disease models to study their progression and to test and refine different treatment approaches. Increasingly, researchers have turned to tissue engineering to address this need for controllable translational disease models. We review existing and potential uses of tissue-engineered disease models in cardiovascular research and suggest guidelines for generating adequate disease models, aimed both at studying disease progression mechanisms and supporting the development of dedicated drug-delivery therapies. This involves the discussion of different requirements for disease models to test drugs, nanoparticles, and drug-eluting devices. In addition to realistic cellular composition, the different mechanical and structural properties that are needed to simulate pathological reality are addressed.
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Affiliation(s)
- Linnea Tscheuschner
- Department of Vascular Surgery, National and Kapodistrian University of Athens, 15772 Athens, Greece
| | - Abraham R. Tzafriri
- Department of Research and Innovation, CBSET Inc., Lexington, MA 02421, USA;
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15
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Katoh K. Effects of Mechanical Stress on Endothelial Cells In Situ and In Vitro. Int J Mol Sci 2023; 24:16518. [PMID: 38003708 PMCID: PMC10671803 DOI: 10.3390/ijms242216518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/26/2023] Open
Abstract
Endothelial cells lining blood vessels are essential for maintaining vascular homeostasis and mediate several pathological and physiological processes. Mechanical stresses generated by blood flow and other biomechanical factors significantly affect endothelial cell activity. Here, we review how mechanical stresses, both in situ and in vitro, affect endothelial cells. We review the basic principles underlying the cellular response to mechanical stresses. We also consider the implications of these findings for understanding the mechanisms of mechanotransducer and mechano-signal transduction systems by cytoskeletal components.
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Affiliation(s)
- Kazuo Katoh
- Laboratory of Human Anatomy and Cell Biology, Faculty of Health Sciences, Tsukuba University of Technology, Tsukuba 305-8521, Japan
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16
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Li Z, Lei P, Hua Q, Zhou L, Song P, Gao L, Zhang S, Cai Q. Surgical Clipping of Intracranial Aneurysms Using a Transcranial Neuroendoscopic Approach. Brain Sci 2023; 13:1544. [PMID: 38002504 PMCID: PMC10669543 DOI: 10.3390/brainsci13111544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/26/2023] [Accepted: 11/01/2023] [Indexed: 11/26/2023] Open
Abstract
OBJECTIVE This retrospective study was performed to evaluate the feasibility and safety of surgically clipping intracranial aneurysms using a transcranial neuroendoscopic approach. METHODS A total of 229 patients with cerebral aneurysms were included in our study, all of whom were treated with clamping surgery at Wuhan University People's Hospital. They were divided into neuroendoscopic and microscopic groups, according to whether or not neuroendoscopy was used for the clamping surgery. We statistically analyzed the patients' baseline data, surgical outcomes, and complications, which were then evaluated to assess the treatment effect. RESULTS The baseline characteristics were not statistically significant, except for gender, for which the proportions of female patients in the two groups were 69 (56.1%) and 46 (43.4%). There were no patients with incomplete aneurysm clamping or parent vessel occlusion in the neuroendoscopic group, and there were 4 (3.8%) and 2 (1.9%) in the microscopic group, respectively; however, there was no statistically significant difference in the comparison of the two groups. The mean operative times of the two groups were 181 min and 154 min, respectively, and were statistically different. However, the mRS scores of the two groups showed no significant difference in patient prognosis. The differences in complications (including limb hemiplegia, hydrocephalus, vision loss, and intracranial infection) were not statistically significant, except for cerebral ischemia, for which the proportions of patients in the two groups were 8 (6.5%) and 16 (15.1%). CONCLUSIONS Neuroendoscopy can provide clear visualization and multi-angle views during aneurysm clipping, which is helpful for ensuring adequate clipping and preventing complications.
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Affiliation(s)
- Zhiyang Li
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Pan Lei
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Qiuwei Hua
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Long Zhou
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Ping Song
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Lun Gao
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
| | - Silei Zhang
- Department of Neurosurgery, Xiantao First People’s Hospital Affiliated to Changjiang University, Xiantao 433000, China;
| | - Qiang Cai
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan 430060, China; (Z.L.); (P.L.); (Q.H.); (L.Z.); (P.S.); (L.G.)
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Cherkaoui I, Bettaibi S, Barkaoui A, Kuznik F. Toward a Mesoscopic Modeling Approach of Magnetohydrodynamic Blood Flow in Pathological Vessels: A Comprehensive Review. Ann Biomed Eng 2023; 51:2415-2440. [PMID: 37639179 DOI: 10.1007/s10439-023-03350-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 08/01/2023] [Indexed: 08/29/2023]
Abstract
The investigation of magnetohydrodynamic (MHD) blood flow within configurations that are pertinent to the human anatomy holds significant importance in the realm of scientific inquiry because of its practical implications within the medical field. This article presents an exhaustive appraisal of the diverse applications of magnetohydrodynamics and their computational modeling in biological contexts. These applications are classified into two categories: simple flow and pulsatile flow. An alternative approach of traditional CFD methods called Lattice Boltzmann Method (LBM), a mesoscopic method based on kinetic theory, is introduced to solve complex problems, such as hemodynamics. The results show that the flow velocity reduces considerably by increasing the magnetic field intensity, and the flow separation area is minimized by the increase of magnetic field strength. The LBM with BGK collision model has shown good results in terms of precision. Finally, this literature review has revealed a number of potential avenues for further research. Suggestions for future works are proposed accordingly.
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Affiliation(s)
- Ikram Cherkaoui
- Laboratoire des Energies Renouvelable et Matériaux Avancés, Université Internationale de Rabat (UIR), Rocade Rabat-Salé, 11100, Rabat, Morocco
| | - Soufiene Bettaibi
- Laboratoire des Energies Renouvelable et Matériaux Avancés, Université Internationale de Rabat (UIR), Rocade Rabat-Salé, 11100, Rabat, Morocco.
| | - Abdelwahed Barkaoui
- Laboratoire des Energies Renouvelable et Matériaux Avancés, Université Internationale de Rabat (UIR), Rocade Rabat-Salé, 11100, Rabat, Morocco
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18
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Tseng YH, Wong MY, Kao CC, Lin CC, Lu MS, Lu CH, Huang YK. The role of venous pressure variability during hemodialysis in the prediction of impending arteriovenous graft occlusion. J Vasc Access 2023; 24:895-903. [PMID: 34772292 DOI: 10.1177/11297298211057381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Elevated venous pressure during hemodialysis (VPHD) is associated with arteriovenous graft (AVG) stenosis. This study investigated the role of VPHD variations in the prediction of impending AVG occlusion. METHODS Data were retrieved from 118 operations to treat AVG occlusion (occlusion group) and 149 operations to treat significant AVG stenosis (stenosis group). In addition to analyzing the VPHD values for the three hemodialysis (HD) sessions prior to the intervention, VPHD values were normalized to mean blood pressure (MBP), blood flow rate (BFR), BFR × MBP, and BFR2 × MBP to yield ratios for analysis. The coefficient of variation (CV) was used to measure relative variations. RESULTS The within-group comparisons for both groups revealed no significant differences in the VPHD mean and CV values among the three HD sessions prior to intervention. However, the CVs for VPHD/MBP, VPHD/(BFR × MBP), and VPHD/(BFR2 × MBP) exhibited significant elevation in the occlusion group during the last HD session prior to intervention compared with both the penultimate and antepenultimate within-group HD data (p < 0.05). In the receiver operating characteristic curve analysis, the CV for VPHD/(BFR2 × MBP) was the only parameter able to discriminate between the last and the penultimate HD outcomes (p < 0.001). According to a multivariate analysis, after controlling for covariates, CV for VPHD/(BFR2 × MBP) >8.76% was associated with a higher risk of AVG thrombosis (odds ratio: 3.17, p < 0.001). CONCLUSIONS Increasing the variation in VPHD/(BFR2 × MBP) may increase the probability of AVG occlusion.
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Affiliation(s)
- Yuan-Hsi Tseng
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
| | - Min Yi Wong
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
- Microbiology Research and Treatment Center, Chiayi Chang Gung Memorial Hospital, Puzi City
- Institute of Imaging and Biomedical Photonics, College of Photonics, National Chiao Tung University, Tainan
| | - Chih-Chen Kao
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
| | - Chien-Chao Lin
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
| | - Ming-Shian Lu
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
| | - Chu-Hsueh Lu
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
| | - Yao-Kuang Huang
- Division of Thoracic and Cardiovascular Surgery, Chiayi Chang Gung Memorial Hospital, Chiayi and Chang Gung University, College of Medicine, Taoyuan
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Chen HW, Chen CH, Fan YJ, Lin CY, Hsu WH, Su IC, Lin CL, Chiang YC, Huang HM. CFD Study of the Effect of the Angle Pattern on Iliac Vein Compression Syndrome. Bioengineering (Basel) 2023; 10:688. [PMID: 37370619 DOI: 10.3390/bioengineering10060688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
Iliac vein compression syndrome (IVCS, or May-Thurner syndrome) occurs due to the compression of the left common iliac vein between the lumbar spine and right common iliac artery. Because most patients with compression are asymptomatic, the syndrome is difficult to diagnose based on the degree of anatomical compression. In this study, we investigated how the tilt angle of the left common iliac vein affects the flow patterns in the compressed blood vessel using three-dimensional computational fluid dynamic (CFD) simulations to determine the flow fields generated after compression sites. A patient-specific iliac venous CFD model was created to verify the boundary conditions and hemodynamic parameter set in this study. Thirty-one patient-specific CFD models with various iliac venous angles were developed using computed tomography (CT) angiograms. The angles between the right or left common iliac vein and inferior vena cava at the confluence level of the common iliac vein were defined as α1 and α2. Flow fields and vortex locations after compression were calculated and compared according to the tilt angle of the veins. Our results showed that α2 affected the incidence of flow field disturbance. At α2 angles greater than 60 degrees, the incidence rate of blood flow disturbance was 90%. In addition, when α2 and α1 + α2 angles were used as indicators, significant differences in tilt angle were found between veins with laminar, transitional, and turbulent flow (p < 0.05). Using this mathematical simulation, we concluded that the tilt angle of the left common iliac vein can be used as an auxiliary indicator to determine IVCS and its severity, and as a reference for clinical decision making.
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Affiliation(s)
- Hsuan-Wei Chen
- Graduate Institute of Biomedical Materials and Tissue Engineering, Taipei Medical University, Taipei 11031, Taiwan
| | - Chao-Hsiang Chen
- Department of Imaging Medicine, Taipei Medical University Hospital, Taipei 11031, Taiwan
| | - Yu-Jui Fan
- School of Biomedical Engineering, Taipei Medical University, Taipei 11031, Taiwan
| | - Chun-Yu Lin
- Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114202, Taiwan
| | - Wen-Hsien Hsu
- Department of Lymphovascular Surgery, Taipei Municipal Wanfang Hospital, Taipei 11600, Taiwan
| | - I-Chang Su
- Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Department of Neurosurgery, Taipei Medical University-Shuang Ho Hospital, Ministry of Health and Welfare, New Taipei City 235041, Taiwan
| | - Chun-Li Lin
- Medical Device Innovation and Translation Center, Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Yuan-Ching Chiang
- Department of Mechanical Engineering, Chinese Culture University, Taipei 111396, Taiwan
| | - Haw-Ming Huang
- School of Dentistry, Taipei Medical University, Taipei 11031, Taiwan
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20
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Silva MLFDA, Gonçalves SDEF, Haniel J, Lucas TC, Huebner R. Comparative study between 1-way and 2-way coupled fluid-structure interaction in numerical simulation of aortic arch aneurysms. AN ACAD BRAS CIENC 2023; 95:e20210859. [PMID: 37255166 DOI: 10.1590/0001-3765202320210859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 12/19/2022] [Indexed: 06/01/2023] Open
Abstract
Hemodynamic forces are related to pathological variations of the cardiovascular system, and numerical simulations for fluid-structure interaction have been systematically used to analyze the behavior of blood flow and the arterial wall in aortic aneurysms. This paper proposes a comparative analysis of 1-way and 2-way coupled fluid-structure interaction for aortic arch aneurysm. The coupling models of fluid-structure interaction were conducted using 3D geometry of the thoracic aorta from computed tomography. Hyperelastic anisotropic properties were estimated for the Holzapfel arterial wall model. The rheological behavior of the blood was modeled by the Carreau-Yasuda model. The results showed that the 1-way approach tends to underestimate von Mises stress, displacement, and strain over the entire cardiac cycle, compared to the 2-way approach. In contrast, the behavior of the variables of flow field, velocity, wall shear stress, and Reynolds number when coupled by the 1-way model was overestimated at the systolic moment and tends to be equal at the diastolic moment. The quantitative differences found, especially during the systole, suggest the use of 2-way coupling in numerical simulations of aortic arch aneurysms due to the hyperelastic nature of the arterial wall, which leads to a strong iteration between the fluid and the arterial wall.
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Affiliation(s)
- Mário Luis F DA Silva
- Programa de Pós-Graduação em Engenharia Mecânica, Universidade Federal de Minas Gerais, Departamento de Engenharia Mecânica, Avenida Presidente Antônio Carlos, 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil
| | - Saulo DE Freitas Gonçalves
- Programa de Pós-Graduação em Engenharia Mecânica, Universidade Federal de Minas Gerais, Departamento de Engenharia Mecânica, Avenida Presidente Antônio Carlos, 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil
| | - Jonathas Haniel
- Programa de Pós-Graduação em Engenharia Mecânica, Universidade Federal de Minas Gerais, Departamento de Engenharia Mecânica, Avenida Presidente Antônio Carlos, 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil
| | - Thabata C Lucas
- Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento de Enfermagem, MGC 367, km 583, 5000, Alto da Jacuba, 39100-000 Diamantina, MG, Brazil
| | - Rudolf Huebner
- Universidade Federal de Minas Gerais, Departamento de Engenharia Mecânica, Avenida Presidente Antônio Carlos, 6627, Pampulha, 31270-901 Belo Horizonte, MG, Brazil
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21
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Csonka D, Kalmár Nagy K, Szakály P, Szukits S, Bogner P, Koller A, Kun S, Wittmann I, Háber I, Horváth I. Optimal Renal Artery-Aorta Angulation Revealed by Flow Simulation. Kidney Blood Press Res 2023; 48:249-259. [PMID: 36940678 PMCID: PMC10173746 DOI: 10.1159/000530169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 03/08/2023] [Indexed: 03/22/2023] Open
Abstract
INTRODUCTION In the circulatory system, the vessel branching angle may have hemodynamic consequences. We hypothesized that there is a hemodynamically optimal range for the renal artery's branching angle. METHODS Data on the posttransplant kinetics of estimated glomerular filtration rate (eGFR) were analyzed according to the donor and implant sides (right-to-right and left-to-right position; n = 46). The renal artery branching angle from the aorta of a randomly selected population was measured using an X-ray angiogram (n = 44). Computational fluid dynamics simulation was used to elucidate the hemodynamic effects of angulation. RESULTS AND DISCUSSION Renal transplant patients receiving a right donor kidney to the right side showed faster adaptation and higher eGFR values than those receiving a left donor kidney to the right side (eGFR: 65 ± 7 vs. 56 ± 6 mL/min/1.73 m2; p < 0.01). The average branching angle on the left side was 78° and that on the right side was 66°. Simulation results showed that the pressure, volume flow, and velocity were relatively constant between 58° and 88°, indicating that this range is optimal for the kidneys. The turbulent kinetic energy does not change significantly between 58° and 78°. CONCLUSION The results suggest that there is an optimal range for the renal artery's branching angle from the aorta where hemodynamic vulnerability caused by the degree of angulation is the lowest, which should be considered during kidney transplantations.
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Affiliation(s)
- Dávid Csonka
- Department of Mechanical Engineering, Faculty of Engineering and Information Technology, University of Pécs, Pécs, Hungary
| | - Károly Kalmár Nagy
- Department of Surgery, Medical School, University of Pécs, Pécs, Hungary
| | - Péter Szakály
- Department of Surgery, Medical School, University of Pécs, Pécs, Hungary
| | - Sándor Szukits
- Department of Diagnostics, Medical School, University of Pécs, Pécs, Hungary
| | - Péter Bogner
- Department of Diagnostics, Medical School, University of Pécs, Pécs, Hungary
| | - Akos Koller
- Department of Morphology and Physiology, Faculty of Health Sciences, Budapest, Hungary
- Department of Translational Medicine, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- Department of Physiology, New York Medical College, Valhalla, NY, USA
| | - Szilárd Kun
- 2nd Department of Medicine and Nephrology-Diabetes Center, Medical School, University of Pécs, Pécs, Hungary
| | - István Wittmann
- 2nd Department of Medicine and Nephrology-Diabetes Center, Medical School, University of Pécs, Pécs, Hungary
| | - István Háber
- Department of Mechanical Engineering, Faculty of Engineering and Information Technology, University of Pécs, Pécs, Hungary
| | - Iván Horváth
- Heart Institute, Medical School, University of Pécs, Pécs, Hungary
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22
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Yi H, Yang Z, Johnson M, Bramlage L, Ludwig B. Developing an in vitro validated 3D in silico internal carotid artery sidewall aneurysm model. Front Physiol 2022; 13:1024590. [PMID: 36605897 PMCID: PMC9810024 DOI: 10.3389/fphys.2022.1024590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 12/08/2022] [Indexed: 12/24/2022] Open
Abstract
Introduction: Direct quantification of hemodynamic factors applied to a cerebral aneurysm (CA) remains inaccessible due to the lack of technologies to measure the flow field within an aneurysm precisely. This study aimed to develop an in vitro validated 3D in silico patient-specific internal carotid artery sidewall aneurysm (ICASA) model which can be used to investigate hemodynamic factors on the CA pathophysiology. Methods: The validated ICASA model was developed by quantifying and comparing the flow field using particle image velocimetry (PIV) measurements and computational fluid dynamics (CFD) simulations. Specifically, the flow field characteristics, i.e., blood flowrates, normalized velocity profiles, flow streamlines, and vortex locations, have been compared at representative time instants in a cardiac pulsatile period in two designated regions of the ICASA model, respectively. One region is in the internal carotid artery (ICA) inlet close to the aneurysm sac, the other is across the middle of the aneurysmal sac. Results and Discussion: The results indicated that the developed computational fluid dynamics model presents good agreements with the results from the parallel particle image velocimetry and flowrate measurements, with relative differences smaller than 0.33% in volumetric flow rate in the ICA and relative errors smaller than 9.52% in averaged velocities in the complex aneurysmal sac. However, small differences between CFD and PIV in the near wall regions were observed due to the factors of slight differences in the 3D printed model, light reflection and refraction near arterial walls, and flow waveform uncertainties. The validated model not only can be further employed to investigate hemodynamic factors on the cerebral aneurysm pathophysiology statistically, but also provides a typical model and guidance for other professionals to evaluate the hemodynamic effects on cerebral aneurysms.
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Affiliation(s)
- Hang Yi
- Department of Mechanical and Materials Engineering, Wright State University, Dayton, OH, United States
| | - Zifeng Yang
- Department of Mechanical and Materials Engineering, Wright State University, Dayton, OH, United States,*Correspondence: Zifeng Yang,
| | - Mark Johnson
- Department of Mechanical and Materials Engineering, Wright State University, Dayton, OH, United States
| | - Luke Bramlage
- Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
| | - Bryan Ludwig
- Boonshoft School of Medicine, Wright State University, Dayton, OH, United States,Division of NeuroInterventional Surgery, Department of Neurology, Wright State University/Premier Health—Clinical Neuroscience Institute, Dayton, OH, United States
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Zhang L, Rashad S, Zhou Y, Niizuma K, Tominaga T. RNF213 loss of function reshapes vascular transcriptome and spliceosome leading to disrupted angiogenesis and aggravated vascular inflammatory responses. J Cereb Blood Flow Metab 2022; 42:2107-2122. [PMID: 35754359 PMCID: PMC9580177 DOI: 10.1177/0271678x221110679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
RNF213 gene mutations are the cause behind Moyamoya disease, a rare cerebrovascular occlusive disease. However, the function of RNF213 in the vascular system and the impact of its loss of function are not yet comprehended. To understand RNF23 function, we performed gene knockdown (KD) in vascular cells and performed various phenotypical analysis as well as extensive transcriptome and epitranscriptome profiling. Our data revealed that RNF213 KD led to disrupted angiogenesis in HUVEC, in part due to downregulation of DNA replication and proliferation pathways. Furthermore, HUVEC cells became sensitive to LPS induced inflammation after RNF213 KD, leading to retarded cell migration and enhanced macrophage transmigration. This was evident at the level of transcriptome as well. Interestingly, RNF213 led to extensive changes in mRNA splicing that were not previously reported. In vascular smooth muscle cells (vSMCs), RNF213 KD led to alteration in cytoskeletal organization, contractility, and vSMCs function related pathways. Finally, RNF213 KD disrupted endothelial-to-vSMCs communication in co-culture models. Overall, our results indicate that RNF213 KD sensitizes endothelial cells to inflammation, leading to altered angiogenesis. Our results shed the light on the important links between RNF213 mutations and inflammatory/immune inducers of MMD and on the unexplored role of epitranscriptome in MMD.
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Affiliation(s)
- Liyin Zhang
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Sherif Rashad
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yuan Zhou
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kuniyasu Niizuma
- Department of Neurosurgical Engineering and Translational Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Neurosurgical Engineering and Translational Neuroscience, Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan.,Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan
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Yi H, Yang Z, Johnson M, Bramlage L, Ludwig B. Hemodynamic characteristics in a cerebral aneurysm model using non-Newtonian blood analogues. PHYSICS OF FLUIDS (WOODBURY, N.Y. : 1994) 2022; 34:103101. [PMID: 36212224 PMCID: PMC9533395 DOI: 10.1063/5.0118097] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/05/2022] [Indexed: 06/16/2023]
Abstract
This study aims to develop an experimentally validated computational fluid dynamics (CFD) model to estimate hemodynamic characteristics in cerebral aneurysms (CAs) using non-Newtonian blood analogues. Blood viscosities varying with shear rates were measured under four temperatures first, which serves as the reference for the generation of blood analogues. Using the blood analogue, particle image velocimetry (PIV) measurements were conducted to quantify flow characteristics in a CA model. Then, using the identical blood properties in the experiment, CFD simulations were executed to quantify the flow patterns, which were used to compare with the PIV counterpart. Additionally, hemodynamic characteristics in the simplified Newtonian and non-Newtonian models were quantified and compared using the experimentally validated CFD model. Results showed the proposed non-Newtonian viscosity model can predict blood shear-thinning properties accurately under varying temperatures and shear rates. Another developed viscosity model based on the blood analogue can well represent blood rheological properties. The comparisons in flow characteristics show good agreements between PIV and CFD, demonstrating the developed CFD model is qualified to investigate hemodynamic factors within CAs. Furthermore, results show the differences of absolute values were insignificant between Newtonian and non-Newtonian fluids in the distributions of wall shear stress (WSS) and oscillatory shear index (OSI) on arterial walls. However, not only does the simplified Newtonian model underestimate WSS and OSI in most regions of the aneurysmal sac, but it also makes mistakes in identifying the high OSI regions on the sac surface, which may mislead the hemodynamic assessment on the pathophysiology of CAs.
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Affiliation(s)
- Hang Yi
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Zifeng Yang
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Mark Johnson
- Department of Mechanical and Material Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435, USA
| | - Luke Bramlage
- Boonshoft School of Medicine, Wright State University, Dayton, Ohio 45435, USA
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25
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On non-Kolmogorov turbulence in blood flow and its possible role in mechanobiological stimulation. Sci Rep 2022; 12:13166. [PMID: 35915207 PMCID: PMC9343407 DOI: 10.1038/s41598-022-16079-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 07/04/2022] [Indexed: 01/09/2023] Open
Abstract
The study of turbulence in physiologic blood flow is important due to its strong relevance to endothelial mechanobiology and vascular disease. Recently, Saqr et al. (Sci Rep 10, 15,492, 2020) discovered non-Kolmogorov turbulence in physiologic blood flow in vivo, traced its origins to the Navier–Stokes equation and demonstrated some of its properties using chaos and hydrodynamic-stability theories. The present work extends these findings and investigates some inherent characteristics of non-Kolmogorov turbulence in monoharmonic and multiharmonic pulsatile flow under ideal physiologic conditions. The purpose of this work is to propose a conjecture for the origins for picoNewton forces that are known to regulate endothelial cells’ functions. The new conjecture relates these forces to physiologic momentum-viscous interactions in the near-wall region of the flow. Here, we used high-resolution large eddy simulation (HRLES) to study pulsatile incompressible flow in a straight pipe of \documentclass[12pt]{minimal}
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\begin{document}$$L/D=20$$\end{document}L/D=20. The simulations presented Newtonian and Carreau–Yasuda fluid flows, at \documentclass[12pt]{minimal}
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\begin{document}$$R{e}_{m}\approx 250$$\end{document}Rem≈250, each represented by one, two and three boundary harmonics. Comparison was established based on maintaining constant time-averaged mass flow rate in all simulations. First, we report the effect of primary harmonics on the global power budget using primitive variables in phase space. Second, we describe the non-Kolmogorov turbulence in frequency domain. Third, we investigate the near-wall coherent structures in time and space domains. Finally, we propose a new conjecture for the role of turbulence in endothelial cells’ mechanobiology. The proposed conjecture correlates near-wall turbulence to a force field of picoNewton scale, suggesting possible relevance to endothelial cells mechanobiology.
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Omar AM, Hassan MH, Daskalakis E, Ates G, Bright CJ, Xu Z, Powell EJ, Mirihanage W, Bartolo PJDS. Geometry-Based Computational Fluid Dynamic Model for Predicting the Biological Behavior of Bone Tissue Engineering Scaffolds. J Funct Biomater 2022; 13:jfb13030104. [PMID: 35997442 PMCID: PMC9397055 DOI: 10.3390/jfb13030104] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/22/2022] [Accepted: 07/24/2022] [Indexed: 02/05/2023] Open
Abstract
The use of biocompatible and biodegradable porous scaffolds produced via additive manufacturing is one of the most common approaches in tissue engineering. The geometric design of tissue engineering scaffolds (e.g., pore size, pore shape, and pore distribution) has a significant impact on their biological behavior. Fluid flow dynamics are important for understanding blood flow through a porous structure, as they determine the transport of nutrients and oxygen to cells and the flushing of toxic waste. The aim of this study is to investigate the impact of the scaffold architecture, pore size and distribution on its biological performance using Computational Fluid Dynamics (CFD). Different blood flow velocities (BFV) induce wall shear stresses (WSS) on cells. WSS values above 30 mPa are detrimental to their growth. In this study, two scaffold designs were considered: rectangular scaffolds with uniform square pores (300, 350, and 450 µm), and anatomically designed circular scaffolds with a bone-like structure and pore size gradient (476–979 µm). The anatomically designed scaffolds provided the best fluid flow conditions, suggesting a 24.21% improvement in the biological performance compared to the rectangular scaffolds. The numerical observations are aligned with those of previously reported biological studies.
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Affiliation(s)
- Abdalla M. Omar
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
- Correspondence: (A.M.O.); (P.J.D.S.B.)
| | - Mohamed H. Hassan
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Evangelos Daskalakis
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Gokhan Ates
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Charlie J. Bright
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Zhanyan Xu
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Emily J. Powell
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
| | - Wajira Mirihanage
- Department of Materials, The University of Manchester, Manchester M13 9PL, UK;
| | - Paulo J. D. S. Bartolo
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (E.D.); (G.A.); (C.J.B.); (Z.X.); (E.J.P.)
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
- Correspondence: (A.M.O.); (P.J.D.S.B.)
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Goligorsky MS. OSCILLATORS IN THE MICROVASCULATURE - GLYCOCALYX AND BEYOND. Am J Physiol Cell Physiol 2022; 323:C432-C438. [PMID: 35759436 PMCID: PMC9359649 DOI: 10.1152/ajpcell.00170.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The growing recognition of abundance of oscillating functions in biological systems has motivated this brief overview which narrows down on the microvasculature. Specifically, it encompasses self-sustained oscillations of blood flow, hematocrit and viscosity at bifurcations; their effects on the oscillations of endothelial glycocalyx, mechanotransduction and its termination to prime endothelial cells for the subsequent mechanical signaling event; oscillating affinity of hyaluronan-CD44 binding domain; spontaneous contractility of actomyosin complexes in the cortical actin web, its effects on the tension of the plasma membrane; reversible effects of sirtuin-1 on endothelial glycocalyx; and effects of plasma membrane tension on endo-and exocytosis. Some potential interactions between those oscillators - their coupling - are discussed together with their transition into chaotic movements. Future in-depth understanding of the oscillatory activities in the microvasculature could serve as a guide to its chronotherapy under pathological conditions.
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Affiliation(s)
- Michael S Goligorsky
- Renal Research Institute and Departments of Medicine, Pharmacology and Physiology, New York Medical College at the Touro University, Valhalla, NY
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28
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Mitsuzuka K, Li Y, Nakayama T, Anzai H, Goanno D, Tupin S, Zhang M, Wang H, Horie K, Ohta M. A Parametric Study of Flushing Conditions for Improvement of Angioscopy Visibility. J Funct Biomater 2022; 13:jfb13020069. [PMID: 35735924 PMCID: PMC9224925 DOI: 10.3390/jfb13020069] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 02/01/2023] Open
Abstract
During an angioscopy operation, a transparent liquid called dextran is sprayed out from a catheter to flush the blood away from the space between the camera and target. Medical doctors usually inject dextran at a constant flow rate. However, they often cannot obtain clear angioscopy visibility because the flushing out of the blood is insufficient. Good flushing conditions producing clear angioscopy visibility will increase the rate of success of angioscopy operations. This study aimed to determine a way to improve the clarity for angioscopy under different values for the parameters of the injection waveform, endoscope position, and catheter angle. We also determined the effect of a stepwise waveform for injecting the dextran only during systole while synchronizing the waveform to the cardiac cycle. To evaluate the visibility of the blood-vessel walls, we performed a computational fluid dynamics (CFD) simulation and calculated the visible area ratio (VAR), representing the ratio of the visible wall area to the total area of the wall at each point in time. Additionally, the normalized integration of the VAR called the area ratio (ARVAR) represents the ratio of the visible wall area as a function of the dextran injection period. The results demonstrate that the ARVAR with a stepped waveform, bottom endoscope, and three-degree-angle catheter results in the highest visibility, around 25 times larger than that under the control conditions: a constant waveform, a center endoscope, and 0 degrees. This set of conditions can improve angioscopy visibility.
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Affiliation(s)
- Kohei Mitsuzuka
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
- Graduate School of Biomedical Engineering, Tohoku University, 6-6 Azaaoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
| | - Yujie Li
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
- Centre for Healthy Futures, Torrens University Australia, 1-51 Foveaux Street, Sydney, NSW 2010, Australia
| | - Toshio Nakayama
- National Institute of Technology, Nara College, 22 Yatacho, Yamatokoriyama 639-1080, Japan;
| | - Hitomi Anzai
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
| | - Daisuke Goanno
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
- Graduate School of Biomedical Engineering, Tohoku University, 6-6 Azaaoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan
| | - Simon Tupin
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
| | - Mingzi Zhang
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
- Macquarie Medical School, Faculty of Medicine, Health, and Human Sciences, Macquarie University, 75 Talavera Rd., Sydney, NSW 2109, Australia
| | - Haoran Wang
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
| | - Kazunori Horie
- Department of Cardiology, Sendai Kousei Hospital, 4-15 Hirose, Aoba-ku, Sendai 980-0873, Japan;
| | - Makoto Ohta
- Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; (K.M.); (Y.L.); (H.A.); (D.G.); (S.T.); (M.Z.); (H.W.)
- Correspondence: ; Tel.: +81-22-217-53-09
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Panther EJ, Lucke-Wold B. Subarachnoid hemorrhage: management considerations for COVID-19. EXPLORATION OF NEUROPROTECTIVE THERAPY 2022; 2:65-73. [PMID: 35340712 PMCID: PMC8951071 DOI: 10.37349/ent.2022.00018] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/18/2022] [Indexed: 02/05/2023]
Abstract
Subarachnoid hemorrhage (SAH) has deleterious outcomes for patients, and during the hospital stay, patients are susceptible to vasospasm and delayed cerebral ischemia. Coronavirus disease 2019 (COVID-19) has been shown to worsen hypertension through angiotensin-converting enzyme 2 (ACE2) activity, therefore, predisposing to aneurysm rupture. The classic renin-angiotensin pathway activation also predisposes to vasospasm and subsequent delayed cerebral ischemia. Matrix metalloproteinase 9 upregulation can lead to an inflammatory surge, which worsens outcomes for patients. SAH patients with COVID-19 are more susceptible to ventilator-associated pneumonia, reversible cerebral vasoconstriction syndrome, and respiratory distress. Emerging treatments are warranted to target key components of the anti-inflammatory cascade. The aim of this review is to explore how the COVID-19 virus and the intensive care unit (ICU) treatment of severe COVID can contribute to SAH.
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Affiliation(s)
- Eric J. Panther
- College of Medicine, University of Florida, Gainesville, Florida 32610, USA
| | - Brandon Lucke-Wold
- Department of Neurosurgery, University of Florida, Gainesville, Florida 32610, USA
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30
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Manchester EL, Pirola S, Salmasi MY, O'Regan DP, Athanasiou T, Xu XY. Evaluation of Computational Methodologies for Accurate Prediction of Wall Shear Stress and Turbulence Parameters in a Patient-Specific Aorta. Front Bioeng Biotechnol 2022; 10:836611. [PMID: 35402418 PMCID: PMC8987126 DOI: 10.3389/fbioe.2022.836611] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/07/2022] [Indexed: 11/21/2022] Open
Abstract
Background: Recent studies suggest that blood flow in main arteries is intrinsically disturbed, even under healthy conditions. Despite this, many computational fluid dynamics (CFD) analyses of aortic haemodynamics make the assumption of laminar flow, and best practices surrounding appropriate modelling choices are lacking. This study aims to address this gap by evaluating different modelling and post-processing approaches in simulations of a patient-specific aorta. Methods: Magnetic resonance imaging (MRI) and 4D flow MRI from a patient with aortic valve stenosis were used to reconstruct the aortic geometry and derive patient-specific inlet and outlet boundary conditions. Three different computational approaches were considered based on assumed laminar or assumed disturbed flow states including low-resolution laminar (LR-Laminar), high-resolution laminar (HR-Laminar) and large-eddy simulation (LES). Each simulation was ran for 30 cardiac cycles and post-processing was conducted on either the final cardiac cycle, or using a phase-averaged approach which utilised all 30 simulated cycles. Model capabilities were evaluated in terms of mean and turbulence-based parameters. Results: All simulation types, regardless of post-processing approach could correctly predict velocity values and flow patterns throughout the aorta. Lower resolution simulations could not accurately predict gradient-derived parameters including wall shear stress and viscous energy loss (largest differences up to 44.6% and 130.3%, respectively), although phase-averaging these parameters improved predictions. The HR-Laminar simulation produced more comparable results to LES with largest differences in wall shear stress and viscous energy loss parameters up to 5.1% and 11.6%, respectively. Laminar-based parameters were better estimated than turbulence-based parameters. Conclusion: Our findings suggest that well-resolved laminar simulations can accurately predict many laminar-based parameters in disturbed flows, but there is no clear benefit to running a HR-Laminar simulation over an LES simulation based on their comparable computational cost. Additionally, post-processing "typical" laminar simulation results with a phase-averaged approach is a simple and cost-effective way to improve accuracy of lower-resolution simulation results.
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Affiliation(s)
| | - Selene Pirola
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
| | - Mohammad Yousuf Salmasi
- Department of Surgery and Cancer, Imperial College London, St Mary's Hospital, London, United Kingdom
| | - Declan P O'Regan
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Thanos Athanasiou
- Department of Surgery and Cancer, Imperial College London, St Mary's Hospital, London, United Kingdom
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
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31
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Kotlyarov S. Diversity of Lipid Function in Atherogenesis: A Focus on Endothelial Mechanobiology. Int J Mol Sci 2021; 22:11545. [PMID: 34768974 PMCID: PMC8584259 DOI: 10.3390/ijms222111545] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/12/2021] [Accepted: 10/21/2021] [Indexed: 12/12/2022] Open
Abstract
Atherosclerosis is one of the most important problems in modern medicine. Its high prevalence and social significance determine the need for a better understanding of the mechanisms of the disease's development and progression. Lipid metabolism and its disorders are one of the key links in the pathogenesis of atherosclerosis. Lipids are involved in many processes, including those related to the mechanoreception of endothelial cells. The multifaceted role of lipids in endothelial mechanobiology and mechanisms of atherogenesis are discussed in this review. Endothelium is involved in ensuring adequate vascular hemodynamics, and changes in blood flow characteristics are detected by endothelial cells and affect their structure and function.
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Affiliation(s)
- Stanislav Kotlyarov
- Department of Nursing, Ryazan State Medical University, 390026 Ryazan, Russia
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32
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Involvement of Microglia in the Pathophysiology of Intracranial Aneurysms and Vascular Malformations-A Short Overview. Int J Mol Sci 2021; 22:ijms22116141. [PMID: 34200256 PMCID: PMC8201350 DOI: 10.3390/ijms22116141] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 12/19/2022] Open
Abstract
Aneurysms and vascular malformations of the brain represent an important source of intracranial hemorrhage and subsequent mortality and morbidity. We are only beginning to discern the involvement of microglia, the resident immune cell of the central nervous system, in these pathologies and their outcomes. Recent evidence suggests that activated proinflammatory microglia are implicated in the expansion of brain injury following subarachnoid hemorrhage (SAH) in both the acute and chronic phases, being also a main actor in vasospasm, considerably the most severe complication of SAH. On the other hand, anti-inflammatory microglia may be involved in the resolution of cerebral injury and hemorrhage. These immune cells have also been observed in high numbers in brain arteriovenous malformations (bAVM) and cerebral cavernomas (CCM), although their roles in these lesions are currently incompletely ascertained. The following review aims to shed a light on the most significant findings related to microglia and their roles in intracranial aneurysms and vascular malformations, as well as possibly establish the course for future research.
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Pandey PK, Paul C, Das MK, Muralidhar K. Assessment and visualization of hemodynamic loading in aneurysm sac and neck: Effect of foam insertion. Proc Inst Mech Eng H 2021; 235:927-939. [PMID: 33971763 DOI: 10.1177/09544119211015569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Shape memory polymer (SMP) foam is often proposed as the future alternative of coils in aneurysm treatment devices. Present work numerically investigates the unsteady, three-dimensional simulation of blood flow in a cerebral aneurysm filled with SMP foam. Simulations are conducted on patient-specific geometries with realistic blood velocity waveform imposed at the inlet while SMP foam is treated as a porous medium. The present study introduces a "loading risk map" that helps to visualize the hemodynamic effect of foam insertion on the aneurysm sac and neck. The loading risk maps suggest that while the SMP foam subdues the flow and wall shear pulsations in the aneurysm sac, the pressure distribution is minimally affected. The maps suggest that while the downstream lip is the most risk-prone site for both geometries, downstream vascular anatomy significantly influences foam efficiency in reducing pressure and wall shear stress loading.
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Affiliation(s)
- Pawan Kumar Pandey
- Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, UP, India
| | - Chandan Paul
- Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, UP, India
| | - Malay K Das
- Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, UP, India
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Ecker P, Sparer A, Lukitsch B, Elenkov M, Seltenhammer M, Crevenna R, Gföhler M, Harasek M, Windberger U. Animal blood in translational research: How to adjust animal blood viscosity to the human standard. Physiol Rep 2021; 9:e14880. [PMID: 34042285 PMCID: PMC8157792 DOI: 10.14814/phy2.14880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 04/27/2021] [Indexed: 11/24/2022] Open
Abstract
Animal blood is used in mock circulations or in forensic bloodstain pattern analysis. Blood viscosity is important in these settings as it determines the driving pressure through biomedical devices and the shape of the bloodstain. However, animal blood can never exactly mimic human blood due to erythrocyte properties differing among species. This results in the species-specific shear thinning behavior of blood suspensions, and it is therefore not enough to adjust the hematocrit of an animal blood sample to mimic the behavior of human blood over the entire range of shear rates that are present in the body. In order to optimize experiments that require animal blood, we need models to adapt the blood samples. We here offer mathematical models derived for each species using a multi linear regression approach to describe the influence of shear rate, hematocrit, and temperature on blood viscosity. Results show that pig blood cannot be recommended for experiments at low flow conditions (<200 s-1 ) even though erythrocyte properties are similar in pigs and humans. However, pig blood mimics human blood excellently at high flow condition. Horse blood is unsuitable as experimental model in this regard. For several studied conditions, sheep blood was the closest match to human blood viscosity among the tested species.
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Affiliation(s)
- Paul Ecker
- Institute of ChemicalEnvironmental and Bioscience EngineeringTU WienViennaAustria
- Institute of Engineering Design and Product DevelopmentTU WienViennaAustria
| | - Andreas Sparer
- Decentralized Biomedical FacilitiesCenter for Biomedical ResearchMedical University of ViennaViennaAustria
| | - Benjamin Lukitsch
- Institute of ChemicalEnvironmental and Bioscience EngineeringTU WienViennaAustria
| | - Martin Elenkov
- Institute of Engineering Design and Product DevelopmentTU WienViennaAustria
| | | | - Richard Crevenna
- University Clinic of Physical MedicineRehabilitation and Occupational MedicineMedical University ViennaViennaAustria
| | - Margit Gföhler
- Institute of Engineering Design and Product DevelopmentTU WienViennaAustria
| | - Michael Harasek
- Institute of ChemicalEnvironmental and Bioscience EngineeringTU WienViennaAustria
| | - Ursula Windberger
- Decentralized Biomedical FacilitiesCenter for Biomedical ResearchMedical University of ViennaViennaAustria
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Zhou Y, Sheremet A, Kennedy JP, DiCola NM, Maciel CB, Burke SN, Maurer AP. Spectrum Degradation of Hippocampal LFP During Euthanasia. Front Syst Neurosci 2021; 15:647011. [PMID: 33967707 PMCID: PMC8102791 DOI: 10.3389/fnsys.2021.647011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/23/2021] [Indexed: 11/13/2022] Open
Abstract
The hippocampal local field potential (LFP) exhibits a strong correlation with behavior. During rest, the theta rhythm is not prominent, but during active behavior, there are strong rhythms in the theta, theta harmonics, and gamma ranges. With increasing running velocity, theta, theta harmonics and gamma increase in power and in cross-frequency coupling, suggesting that neural entrainment is a direct consequence of the total excitatory input. While it is common to study the parametric range between the LFP and its complementing power spectra between deep rest and epochs of high running velocity, it is also possible to explore how the spectra degrades as the energy is completely quenched from the system. Specifically, it is unknown whether the 1/f slope is preserved as synaptic activity becomes diminished, as low frequencies are generated by large pools of neurons while higher frequencies comprise the activity of more local neuronal populations. To test this hypothesis, we examined rat LFPs recorded from the hippocampus and entorhinal cortex during barbiturate overdose euthanasia. Within the hippocampus, the initial stage entailed a quasi-stationary LFP state with a power-law feature in the power spectral density. In the second stage, there was a successive erosion of power from high- to low-frequencies in the second stage that continued until the only dominant remaining power was <20 Hz. This stage was followed by a rapid collapse of power spectrum toward the absolute electrothermal noise background. As the collapse of activity occurred later in hippocampus compared with medial entorhinal cortex, it suggests that the ability of a neural network to maintain the 1/f slope with decreasing energy is a function of general connectivity. Broadly, these data support the energy cascade theory where there is a cascade of energy from large cortical populations into smaller loops, such as those that supports the higher frequency gamma rhythm. As energy is pulled from the system, neural entrainment at gamma frequency (and higher) decline first. The larger loops, comprising a larger population, are fault-tolerant to a point capable of maintaining their activity before a final collapse.
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Affiliation(s)
- Yuchen Zhou
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States
| | - Alex Sheremet
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States.,Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Jack P Kennedy
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Nicholas M DiCola
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Carolina B Maciel
- Division of Neurocritical Care, Department of Neurology, University of Florida, Gainesville, FL, United States
| | - Sara N Burke
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States
| | - Andrew P Maurer
- Engineering School of Sustainable Infrastructure and Environment, University of Florida, Gainesville, FL, United States.,Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States.,Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States
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Model Verification and Error Sensitivity of Turbulence-Related Tensor Characteristics in Pulsatile Blood Flow Simulations. FLUIDS 2020. [DOI: 10.3390/fluids6010011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Model verification, validation, and uncertainty quantification are essential procedures to estimate errors within cardiovascular flow modeling, where acceptable confidence levels are needed for clinical reliability. While more turbulent-like studies are frequently observed within the biofluid community, practical modeling guidelines are scarce. Verification procedures determine the agreement between the conceptual model and its numerical solution by comparing for example, discretization and phase-averaging-related errors of specific output parameters. This computational fluid dynamics (CFD) study presents a comprehensive and practical verification approach for pulsatile turbulent-like blood flow predictions by considering the amplitude and shape of the turbulence-related tensor field using anisotropic invariant mapping. These procedures were demonstrated by investigating the Reynolds stress tensor characteristics in a patient-specific aortic coarctation model, focusing on modeling-related errors associated with the spatiotemporal resolution and phase-averaging sampling size. Findings in this work suggest that attention should also be put on reducing phase-averaging related errors, as these could easily outweigh the errors associated with the spatiotemporal resolution when including too few cardiac cycles. Also, substantially more cycles are likely needed than typically reported for these flow regimes to sufficiently converge the phase-instant tensor characteristics. Here, higher degrees of active fluctuating directions, especially of lower amplitudes, appeared to be the most sensitive turbulence characteristics.
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