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Altundemir S, Lashkarinia SS, Pekkan K, Uğuz AK. Interstitial flow, pressure and residual stress in the aging carotid artery model in FEBio. Biomech Model Mechanobiol 2024; 23:179-192. [PMID: 37668853 DOI: 10.1007/s10237-023-01766-7] [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: 05/10/2023] [Accepted: 08/16/2023] [Indexed: 09/06/2023]
Abstract
Vascular smooth muscle cells (VSMCs) are subject to interstitial flow-induced shear stress, which is a critical parameter in cardiovascular disease progression. Transmural pressure loading and residual stresses alter the hydraulic conductivity of the arterial layers and modulate the interstitial fluid flux through the arterial wall. In this paper, a biphasic multilayer model of a common carotid artery (CCA) with anisotropic fiber-reinforced soft tissue and strain-dependent permeability is developed in FEBio software. After the verification of the numerical predictions, age-related arterial thickening and stiffening effects on arterial deformation and interstitial flow are computed under physiological geometry and physical parameters. We found that circumferential residual stress shifts outward in each layer and its gradient increases up to 6 times with aging. Internally pressurized CCA displays nonlinear deformation. In the aged artery, the circumferential stress becomes greater on the media layer (82-158 kPa) and lower on the intima and adventitia (19-23 kPa and 25-28 kPa, respectively). The radial compression of the intima reduces the total hydraulic conductivity by 48% in the young and 16% in the aged arterial walls. Consequently, the average radial interstitial flux increases with pressure by 14% in the young and 91% in the aged arteries. Accordingly, the flow shear stress experienced by the VSMCs becomes more significant for aged arteries, which may accelerate cardiovascular disease progression compared to young arteries.
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Affiliation(s)
- Sercan Altundemir
- Department of Chemical Engineering, Boğaziçi University, Istanbul, 34342, Turkey.
| | - S Samaneh Lashkarinia
- Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
- Department of Mechanical Engineering, Koç University, Istanbul, 34450, Turkey
| | - Kerem Pekkan
- Department of Mechanical Engineering, Koç University, Istanbul, 34450, Turkey
| | - A Kerem Uğuz
- Department of Chemical Engineering, Boğaziçi University, Istanbul, 34342, Turkey.
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2
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Behrangzade A, Keeney HR, Martinet KM, Wagner WR, Vande Geest JP. Mechanical alterations of electrospun poly(ϵ-caprolactone) in response to convective thermobonding. J Biomed Mater Res B Appl Biomater 2023; 111:622-632. [PMID: 36221771 PMCID: PMC10600560 DOI: 10.1002/jbm.b.35181] [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: 05/04/2022] [Revised: 09/07/2022] [Accepted: 09/22/2022] [Indexed: 01/21/2023]
Abstract
Vascular graft failure has persisted as a major clinical problem. Mechanical, structural, and transport properties of vascular grafts are critical factors that substantially affect their function and thus the outcome of implantation. The manufacturing method, post-processing technique, and material of choice have a significant impact on these properties. The goal of this work is to use thermal treatment to modulate the transport properties of PCL-based vascular engineered constructs. To this end, we electrospun PCL tubular constructs and thermally bonded the electrospun fibers in a convective oven at various temperatures (54, 57, and 60°C) and durations of treatment (15, 30, and 45 s). The effects of fiber thermal bonding (thermobonding) on the transport, mechanical, and structural properties of PCL tubular constructs were characterized. Increasing the temperature and treatment duration enhanced the degree of thermobonding by removing the interconnected void and fusing the fibers. Thermobonding at 57°C and 60°C for longer than 30 s increased the median tangential modulus (E = 126.1 MPa, [IQR = 20.7]), mean suture retention (F = 193.8 g, [SD = 18.5]), and degradation rate while it decreased the median permeability (kA = 0 m/s), and median thickness (t = 60 μm, [IQR = 2.5]). In particular, the thermobonding at 57°C allowed a finer modulation of permeability via treatment duration. We believe that the thermobonding method can be utilized to modulate the properties of vascular engineered constructs which can be useful in designing functional vascular grafts.
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Affiliation(s)
- Ali Behrangzade
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Hannah R. Keeney
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Katarina M. Martinet
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - William R. Wagner
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Jonathan P. Vande Geest
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Mechanical Engineering and Material Science, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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3
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Li X, Liu X, Liang Y, Deng X, Fan Y. Spatiotemporal changes of local hemodynamics and plaque components during atherosclerotic progression in rabbit. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 220:106814. [PMID: 35523025 DOI: 10.1016/j.cmpb.2022.106814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 02/22/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND OBJECTIVE Recent evidence demonstrates that the atherogenic process is discontinuous. Our goal is to study changes of plaque components and local hemodynamics during atherosclerotic progression. METHODS The histological and immunohistochemical staining of high-fat diet rabbit aorta were evaluated at 0, 8, 10 and 12 weeks, respectively. In addition, the blood flow and LDL transport were simulated at the above four time points. RESULTS The plaque thickness at different characteristic regions increased at different rates. The collagen continued to increase, while the elastin, fibronectin, macrophages and smooth muscle cells increased first and then decreased. The relative surface LDL concentration decreased at 8 weeks, and then it increased first and decreased slightly. Meanwhile, the hemodynamic environment became better firstly at 8 weeks, then got slightly worse and lastly improved again. CONCLUSIONS The local hemodynamics and plaque components vary nonlinearly during atherosclerotic progression in rabbit aorta.
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Affiliation(s)
- Xiaoyin Li
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Chinese Education Ministry, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Xiao Liu
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Chinese Education Ministry, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China.
| | - Ye Liang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing, China
| | - Xiaoyan Deng
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Chinese Education Ministry, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Yubo Fan
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Chinese Education Ministry, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China; School of Engineering Medicine, Beihang University, Beijing, China.
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4
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Fukui W, Ujihara Y, Nakamura M, Sugita S. Direct visualization of interstitial flow distribution in aortic walls. Sci Rep 2022; 12:5381. [PMID: 35354879 PMCID: PMC8969162 DOI: 10.1038/s41598-022-09304-8] [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: 12/09/2021] [Accepted: 03/21/2022] [Indexed: 12/05/2022] Open
Abstract
Vascular smooth muscle cells are exposed to interstitial flow across aortic walls. Fluid shear stress changes the phenotype of smooth muscle cells to the synthetic type; hence, the fast interstitial flow might be related to aortic diseases. In this study, we propose a novel method to directly measure the interstitial flow velocity from the spatiotemporal changes in the concentration of a fluorescent dye. The lumen of a mouse thoracic aorta was filled with a fluorescent dye and pressurized in ex vivo. The flow of the fluorescent dye from the intimal to the adventitial sides was successfully visualized under a two-photon microscope. The flow velocity was determined by applying a one-dimensional advection–diffusion equation to the kymograph obtained from a series of fluorescent images. The results confirmed a higher interstitial flow velocity in the aortic walls under higher intraluminal pressure. A comparison of the interstitial flow velocity in the radial direction showed faster flow on the more intimal side, where hyperplasia is often found in hypertension. These results indicate that the proposed method can be used to visualize the interstitial flow directly and thus, determine the local interstitial flow velocity.
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Guang Y, Cocciolone AJ, Crandall CL, Johnston BB, Setton LA, Wagenseil JE. A multiphasic model for determination of water and solute transport across the arterial wall: effects of elastic fiber defects. ARCHIVE OF APPLIED MECHANICS = INGENIEUR-ARCHIV 2022; 92:447-459. [PMID: 35386426 PMCID: PMC8983017 DOI: 10.1007/s00419-021-01985-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Transport of solute across the arterial wall is a process driven by both convection and diffusion. In disease, the elastic fibers in the arterial wall are disrupted and lead to altered fluid and mass transport kinetics. A computational mixture model was used to numerically match previously published data of fluid and solute permeation experiments in groups of mouse arteries with genetic (knockout of fibulin-5) or chemical (treatment with elastase) disruption of elastic fibers. A biphasic model of fluid permeation indicated the governing property to be the hydraulic permeability, which was estimated to be 1.52×10-9, 1.01×10-8, and 1.07×10-8 mm4/μN.s for control, knockout, and elastase groups, respectively. A multiphasic model incorporating solute transport was used to estimate effective diffusivities that were dependent on molecular weight, consistent with expected transport behaviors in multiphasic biological tissues. The effective diffusivity for the 4 kDA FITC-dextran solute, but not the 70 or 150 kDa FITC-dextran solutes, was dependent on elastic fiber structure, with increasing values from control to knockout to elastase groups, suggesting that elastic fiber disruption affects transport of lower molecular weight solutes. The model used here sets the groundwork for future work investigating transport through the arterial wall.
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Affiliation(s)
- Young Guang
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
| | - Austin J Cocciolone
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
| | - Christie L Crandall
- Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO, USA
| | - Benjamin B Johnston
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
| | - Lori A Setton
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
| | - Jessica E Wagenseil
- Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO, USA
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Rowland E, Bailey E, Weinberg P. Estimating Arterial Cyclic Strain from the Spacing of Endothelial Nuclei. EXPERIMENTAL MECHANICS 2021; 61:171-190. [PMID: 33510542 PMCID: PMC7116634 DOI: 10.1007/s11340-020-00655-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND The non-uniform distribution of atherosclerosis within the arterial system is widely attributed to variation in haemodynamic wall shear stress. It may also depend on variation in pressure-induced stresses and strains within the arterial wall; these have been less widely investigated, at least in part because of a lack of suitable techniques. OBJECTIVES Here we show that local arterial strain can be determined from impressions left by endothelial cells on the surface of vascular corrosion casts made at different pressures, even though only one pressure can be examined in each vessel. The pattern of pits in the cast caused by protruding endothelial nuclei was subject to "retro-deformation" to identify the pattern that would have occurred in the absence of applied stresses. METHODS Retaining the nearest-neighbour pairs found under this condition, changes in nearest-neighbour vectors were calculated for the pattern seen in the cast, and the ratio of mean changes at different pressures determined. This approach removes errors in simple nearest-neighbour analyses caused by the nearest neighbour changing as deformation occurs. RESULTS The accuracy, precision and robustness of the approach were validated using simulations. The method was implemented using confocal microscopy of casts of the rabbit aorta made at systolic and diastolic pressures; results agreed well with the ratio of the macroscopic dimensions of the casts. CONCLUSIONS Applying the new technique to areas around arterial branches could support or refute the hypothesis that the development of atherosclerosis is influenced by mural strain, and the method may be applicable to other tissues.
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Affiliation(s)
- E.M. Rowland
- Department of Biomedical Engineering, Imperial College London, London SW7 2AZ, UK
| | - E.L. Bailey
- Department of Biomedical Engineering, Imperial College London, London SW7 2AZ, UK
| | - P.D. Weinberg
- Department of Biomedical Engineering, Imperial College London, London SW7 2AZ, UK
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Haslach HW, Gipple J, Harwerth J, Rabin J. Interstitial fluid-solid interaction within aneurysmal and non-pathological human ascending aortic tissue under translational sinusoidal shear deformation. Acta Biomater 2020; 113:452-463. [PMID: 32645439 DOI: 10.1016/j.actbio.2020.06.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/25/2020] [Accepted: 06/30/2020] [Indexed: 11/15/2022]
Abstract
The interaction shear force between internal interstitial fluid motion and the solid circumferential-longitudinal medial lamellae helps generate the shear stress involved in dissection of human ascending aorta aneurysmal or non-pathologic tissue. Frequency analysis parameters from the total shear stress versus time response to translational 1 Hz sinusoidal shear deformation over 50 cycles measure the interaction with respect to the three factors: tissue type, sinusoidal deformation amplitude and direction of the shear deformation. Significant 1, 3, and 5 Hz components exist in this order of descending magnitude for shear deformation amplitudes of either 25% or 50% of the specimen length. Evaporation tests indicate that the amount of free water in both aneurysmal and non-pathological tissue is nearly the same. The interstitial fluid-solid interaction under shear deformation is visible in the shoulders of the total shear stress versus time response curve that are caused by the 3 Hz component. During a single deformation cycle, the ratio of the amplitudes of the 3 Hz and the 1 Hz components measures the normalized amount of interaction. Under translational sinusoidal shear deformation at 25% amplitude, this interaction ratio is statistically smaller in non-pathologic than in aneurysmal human ascending aortic tissue in the circumferential direction. The frequency analysis parameters provide evidence that the structural changes in aneurysmal tissue induce an increase in the interstitial fluid-medial solid interaction shear force which contributes to the propensity for aneurysmal rupture. STATEMENT OF SIGNIFICANCE: Circumferential shear force between the interstitial fluid and medial lamellae within the human ascending aortic wall is demonstrably greater in aneurysmal than non-pathologic tissue. This force likely increases with medial elastin degeneration and may facilitate the dissection propensity in aneurysmal tissue. The 3 Hz component in frequency analyses of the total shear stress versus time curve produced by 1 Hz sinusoidal translational shear deformation measures the fluid-solid interaction shear force that is otherwise difficult to isolate. This non-standard examination of the interstitial fluid interaction helps clarify clinical mechanical implications of structural differences between aneurysmal and non-pathologic human ascending aortic tissue. The aneurysmal dissection susceptibility does not appear to depend on the amount of interstitial fluid or the wall thickness compared to non-pathologic tissue.
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Affiliation(s)
- Henry W Haslach
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA.
| | - Jenna Gipple
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Jason Harwerth
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Joseph Rabin
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA; R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, MD, USA
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8
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Guo Z, Grijpma D, Poot A. Leachable Poly(Trimethylene Carbonate)/CaCO 3 Composites for Additive Manufacturing of Microporous Vascular Structures. MATERIALS 2020; 13:ma13153435. [PMID: 32759759 PMCID: PMC7435882 DOI: 10.3390/ma13153435] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/10/2020] [Accepted: 07/27/2020] [Indexed: 01/21/2023]
Abstract
The aim of this work was to fabricate microporous poly(trimethylene carbonate) (PTMC) vascular structures by stereolithography (SLA) for applications in tissue engineering and organ models. Leachable CaCO3 particles with an average size of 0.56 μm were used as porogens. Composites of photocrosslinkable PTMC and CaCO3 particles were cast on glass plates, crosslinked by ultraviolet light treatment and leached in watery HCl solutions. In order to obtain interconnected pore structures, the PTMC/CaCO3 composites had to contain at least 30 vol % CaCO3. Leached PTMC films had porosities ranging from 33% to 71% and a pore size of around 0.5 μm. The mechanical properties of the microporous PTMC films matched with those of natural blood vessels. Resins based on PTMC/CaCO3 composites with 45 vol % CaCO3 particles were formulated and successfully used to build vascular structures of various shapes and sizes by SLA. The intrinsic permeabilities of the microporous PTMC films and vascular structures were at least one order of magnitude higher than reported for the extracellular matrix, indicating no mass transfer limitations in the case of cell seeding.
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9
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Condemi F, Campisi S, Viallon M, Croisille P, Avril S. Relationship Between Ascending Thoracic Aortic Aneurysms Hemodynamics and Biomechanical Properties. IEEE Trans Biomed Eng 2020; 67:949-956. [DOI: 10.1109/tbme.2019.2924955] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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10
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Michel JB, Jondeau G, Milewicz DM. From genetics to response to injury: vascular smooth muscle cells in aneurysms and dissections of the ascending aorta. Cardiovasc Res 2019; 114:578-589. [PMID: 29360940 DOI: 10.1093/cvr/cvy006] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 01/16/2018] [Indexed: 12/20/2022] Open
Abstract
Vascular smooth muscle cells (vSMCs) play a crucial role in both the pathogenesis of Aneurysms and Dissections of the ascending thoracic aorta (TAAD) in humans and in the associated adaptive compensatory responses, since thrombosis and inflammatory processes are absent in the majority of cases. Aneurysms and dissections share numerous characteristics, including aetiologies and histopathological alterations: vSMC disappearance, medial areas of mucoid degeneration, and extracellular matrix (ECM) breakdown. Three aetiologies predominate in TAAD in humans: (i) genetic causes in heritable familial forms, (ii) an association with bicuspid aortic valves, and (iii) a sporadic degenerative form linked to the aortic aging process. Genetic forms include mutations in vSMC genes encoding for molecules of the ECM or the TGF-β pathways, or participating in vSMC tone. On the other hand, aneurysms and dissections, whatever their aetiologies, are characterized by an increase in wall permeability leading to transmural advection of plasma proteins which could interact with vSMCs and ECM components. In this context, blood-borne plasminogen appears to play an important role, because its outward convection through the wall is increased in TAAD, and it could be converted to active plasmin at the vSMC membrane. Active plasmin can induce vSMC disappearance, proteolysis of adhesive proteins, activation of MMPs and release of TGF-β from its ECM storage sites. Conversely, vSMCs could respond to aneurysmal biomechanical and proteolytic injury by an epigenetic phenotypic switch, including constitutional overexpression and nuclear translocation of Smad2 and an increase in antiprotease and ECM protein synthesis. In contrast, such an epigenetic phenomenon is not observed in dissections. In this context, dysfunction of proteins involved in vSMC tone are interesting to study, particularly in interaction with plasma protein transport through the wall and TGF-β activation, to establish the relationship between these dysfunctions and ECM proteolysis.
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Affiliation(s)
- Jean-Baptiste Michel
- UMR 1148, Laboratory for Translational Vascular Science, Inserm and Paris 7- Denis Diderot University, Xavier Bichat Hospital, 75018 Paris, France
| | - Guillaume Jondeau
- UMR 1148, Laboratory for Translational Vascular Science, Inserm and Paris 7- Denis Diderot University, Xavier Bichat Hospital, 75018 Paris, France.,Cardiology Department, National Reference Center for Marfan Syndrome and Related Diseases, APHP Hopital Bichat, 75018 Paris
| | - Dianna M Milewicz
- Division of Medical Genetics, Department of Internal Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA
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Andreozzi A, Iasiello M, Netti PA. A thermoporoelastic model for fluid transport in tumour tissues. J R Soc Interface 2019; 16:20190030. [PMID: 31138093 DOI: 10.1098/rsif.2019.0030] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In this paper, the effect of coupled thermal dilation and stress on interstitial fluid transport in tumour tissues is evaluated. The tumour is modelled as a spherical deformable poroelastic medium embedded with interstitial fluid, while the transvascular fluid flow is modelled as a uniform distribution of fluid sink and source points. A hyperbolic-decay radial function is used to model the heat source generation along with a rapid decay of tumour blood flow. Governing equations for displacement, fluid flow and temperature are first scaled and then solved with a finite-element scheme. Results are compared with analytical solutions from the literature, while results are presented for different scaling parameters to analyse the various physical phenomena. Results show that temperature affects pressure and velocity fields through the deformable medium. Finally, simulations are performed by assuming that the heat source is periodic, in order to assess the extent to which this condition affects the velocity field. It is reported that in some cases, especially for periodic heating, the combination of thermoelastic and poroelastic deformation led to no monotonic pressure distribution, which can be interesting for applications such as macromolecule drug delivery, in which the advective contribution is very important owing to the low diffusivity.
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Affiliation(s)
- Assunta Andreozzi
- 1 Dipartimento di Ingegneria Industriale, Università degli Studi di Napoli Federico II , Napoli , Italy
| | - Marcello Iasiello
- 1 Dipartimento di Ingegneria Industriale, Università degli Studi di Napoli Federico II , Napoli , Italy
| | - Paolo Antonio Netti
- 2 Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli Federico II , Napoli , Italy
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Raja J, Condemi F, Campisi S, Viallon M, Croisille P, Avril S. Correlation between wall shear stress and wall rupture properties in ascending thoracic aortic aneurysms. Comput Methods Biomech Biomed Engin 2019. [DOI: 10.1080/10255842.2020.1713478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Jayendiran Raja
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, Saint-Etienne, France
| | - Francesca Condemi
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, Saint-Etienne, France
| | - Salvatore Campisi
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, Saint-Etienne, France
- Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR5520, INSERM U1206, CREATIS, Saint-Etienne, France
| | - Magalie Viallon
- CHU Hôpital Nord, Saint-Etienne, France
- Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR5520, INSERM U1206, CREATIS, Saint-Etienne, France
| | - Pierre Croisille
- CHU Hôpital Nord, Saint-Etienne, France
- Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR5520, INSERM U1206, CREATIS, Saint-Etienne, France
| | - Stéphane Avril
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, Saint-Etienne, France
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Marino M, Pontrelli G, Vairo G, Wriggers P. A chemo-mechano-biological formulation for the effects of biochemical alterations on arterial mechanics: the role of molecular transport and multiscale tissue remodelling. J R Soc Interface 2018; 14:rsif.2017.0615. [PMID: 29118114 DOI: 10.1098/rsif.2017.0615] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/11/2017] [Indexed: 12/21/2022] Open
Abstract
This paper presents a chemo-mechano-biological framework for arterial physiopathology. The model accounts for the fine remodelling in the multiscale hierarchical arrangement of tissue constituents and for the diffusion of molecular species involved in cell-cell signalling pathways. Effects in terms of alterations in arterial compliance are obtained. A simple instructive example is introduced. Although oversimplified with respect to realistic case studies, the proposed application mimics the biochemical activity of matrix metalloproteinases, transforming growth factors beta and interleukins on tissue remodelling. Effects of macrophage infiltration, of intimal thickening and of a healing phase are investigated, highlighting the corresponding influence on arterial compliance. The obtained results show that the present approach is able to capture changes in arterial mechanics as a consequence of the alterations in tissue biochemical environment and cellular activity, as well as to incorporate the protective role of both autoimmune responses and pharmacological treatments.
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Affiliation(s)
- Michele Marino
- Institut für Kontinuumsmechanik, Leibniz Universität Hannover, Hannover, Germany
| | - Giuseppe Pontrelli
- Istituto per le Applicazioni del Calcolo, National Research Council (CNR), Rome, Italy
| | - Giuseppe Vairo
- Dipartimento di Ingegneria Civile e Ingegneria Informatica, Università degli Studi di Roma 'Tor Vergata', Rome, Italy
| | - Peter Wriggers
- Institut für Kontinuumsmechanik, Leibniz Universität Hannover, Hannover, Germany
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Jallepalli A, Docampo-Sanchez J, Ryan JK, Haimes R, Kirby RM. On the Treatment of Field Quantities and Elemental Continuity in FEM Solutions. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2018; 24:903-912. [PMID: 28866517 DOI: 10.1109/tvcg.2017.2744058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
As the finite element method (FEM) and the finite volume method (FVM), both traditional and high-order variants, continue their proliferation into various applied engineering disciplines, it is important that the visualization techniques and corresponding data analysis tools that act on the results produced by these methods faithfully represent the underlying data. To state this in another way: the interpretation of data generated by simulation needs to be consistent with the numerical schemes that underpin the specific solver technology. As the verifiable visualization literature has demonstrated: visual artifacts produced by the introduction of either explicit or implicit data transformations, such as data resampling, can sometimes distort or even obfuscate key scientific features in the data. In this paper, we focus on the handling of elemental continuity, which is often only continuous or piecewise discontinuous, when visualizing primary or derived fields from FEM or FVM simulations. We demonstrate that traditional data handling and visualization of these fields introduce visual errors. In addition, we show how the use of the recently proposed line-SIAC filter provides a way of handling elemental continuity issues in an accuracy-conserving manner with the added benefit of casting the data in a smooth context even if the representation is element discontinuous.
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15
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Li X, Liu X, Zhang P, Feng C, Sun A, Kang H, Deng X, Fan Y. Numerical simulation of haemodynamics and low-density lipoprotein transport in the rabbit aorta and their correlation with atherosclerotic plaque thickness. J R Soc Interface 2017; 14:rsif.2017.0140. [PMID: 28424305 DOI: 10.1098/rsif.2017.0140] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 03/20/2017] [Indexed: 12/25/2022] Open
Abstract
Two mechanisms of shear stress and mass transport have been recognized to play an important role in the development of localized atherosclerosis. However, their relationship and roles in atherogenesis are still obscure. It is necessary to investigate quantitatively the correlation among low-density lipoproteins (LDL) transport, haemodynamic parameters and plaque thickness. We simulated blood flow and LDL transport in rabbit aorta using computational fluid dynamics and evaluated plaque thickness in the aorta of a high-fat-diet rabbit. The numerical results show that regions with high luminal LDL concentration tend to have severely negative haemodynamic environments (HEs). However, for regions with moderately and slightly high luminal LDL concentration, the relationship between LDL concentration and the above haemodynamic indicators is not clear cut. Point-by-point correlation with experimental results indicates that severe atherosclerotic plaque corresponds to high LDL concentration and seriously negative HEs, less severe atherosclerotic plaque is related to either moderately high LDL concentration or moderately negative HEs, and there is almost no atherosclerotic plaque in regions with both low LDL concentration and positive HEs. In conclusion, LDL distribution is closely linked to blood flow transport, and the synergetic effects of luminal surface LDL concentration and wall shear stress-based haemodynamic indicators may determine plaque thickness.
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Affiliation(s)
- Xiaoyin Li
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Xiao Liu
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Peng Zhang
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Chenglong Feng
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Anqiang Sun
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Hongyan Kang
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Xiaoyan Deng
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China .,National Research Center for Rehabilitation Technical Aids, Beijing, People's Republic of China
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16
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Noradrenaline has opposing effects on the hydraulic conductance of arterial intima and media. J Biomech 2017; 54:4-10. [PMID: 28256247 PMCID: PMC5380660 DOI: 10.1016/j.jbiomech.2017.01.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 12/12/2016] [Accepted: 01/14/2017] [Indexed: 11/23/2022]
Abstract
The uptake of circulating macromolecules by the arterial intima is thought to be a key step in atherogenesis. Such transport is dominantly advective, so elucidating the mechanisms of water transport is important. The relation between vasoactive agents and water transport in the arterial wall is incompletely understood. Here we applied our recently-developed combination of computational and experimental methods to investigate the effects of noradrenaline (NA) on hydraulic conductance of the wall (Lp), medial extracellular matrix volume fraction (ϕECM) and medial permeability (K11) in the rat abdominal aorta. Experimentally, we found that physiological NA concentrations were sufficient to induce SMC contraction and produced significant decreases in Lp and increases in ϕECM. Simulation results based on 3D confocal images of the extracellular volume showed a corresponding increase in K11, attributed to the opening of the ECM. Conversion of permeabilities to layer-specific resistances revealed that although the total wall resistance increased, medial resistance decreased, suggesting an increase in intimal resistance upon application of NA.
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