Biomechanics and Modeling in Mechanobiology最新文献

{"title":"A morpho-viscoelasticity theory for growth in proliferating aggregates","authors":"Prakhar Bandil,&nbsp;Franck J. Vernerey","doi":"10.1007/s10237-024-01886-8","DOIUrl":"10.1007/s10237-024-01886-8","url":null,"abstract":"<div><p>Despite significant research efforts in the continuum modeling of biological growth, certain aspects have been overlooked. For instance, numerous investigations have examined the influence of morphogenetic cell behaviors, like division and intercalation, on the mechanical response of passive (non-growing) tissues. Yet, their impact on active growth dynamics remains inadequately explored. A key reason for this inadequacy stems from challenges in the continuum treatment of cell-level processes. While some coarse-grained models have been proposed to address these shortcomings, a focus on cell division and cell expansion has been missing, rendering them unusable when it comes to modeling growth. Moreover, existing studies are limited to two-dimensional tissues and are yet to be formally extended to three-dimensional multicellular systems. To address these limitations, we here present a generalized multiscale model for three-dimensional aggregates that accounts for complex morphogenetic movements that include division, expansion, and intercalation. The proposed continuum theory thus allows for a comprehensive exploration into the growth and dissipation mechanics of proliferating aggregates, such as spheroids and organoids. \u0000</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"2155 - 2176"},"PeriodicalIF":3.0,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Personalized computational electro-mechanics simulations to optimize cardiac resynchronization therapy","authors":"Emilia Capuano,&nbsp;Francesco Regazzoni,&nbsp;Massimiliano Maines,&nbsp;Silvia Fornara,&nbsp;Vanessa Locatelli,&nbsp;Domenico Catanzariti,&nbsp;Simone Stella,&nbsp;Fabio Nobile,&nbsp;Maurizio Del Greco,&nbsp;Christian Vergara","doi":"10.1007/s10237-024-01878-8","DOIUrl":"10.1007/s10237-024-01878-8","url":null,"abstract":"<div><p>In this study, we present a computational framework designed to evaluate virtual scenarios of cardiac resynchronization therapy (CRT) and compare their effectiveness based on relevant clinical biomarkers. Our approach involves electro-mechanical numerical simulations personalized, for patients with left bundle branch block, by means of a calibration obtained using data from Electro-Anatomical Mapping System (EAMS) measures acquired by cardiologists during the CRT procedure, as well as ventricular pressures and volumes, both obtained pre-implantation. We validate the calibration by using EAMS data coming from right pacing conditions. Three patients with fibrosis and three without are considered to explore various conditions. Our virtual scenarios consist of personalized numerical experiments, incorporating different positions of the left electrode along reconstructed epicardial veins; different locations of the right electrode; different ventriculo-ventricular delays. The aim is to offer a comprehensive tool capable of optimizing CRT efficiency for individual patients. We provide preliminary answers on optimal electrode placement and delay, by computing some relevant biomarkers such as <span>(dP/dt_{max})</span>, ejection fraction, stroke work. From our numerical experiments, we found that the latest activated segment during sinus rhythm is an effective choice for the non-fibrotic cases for the location of the left electrode. Also, our results showed that the activation of the right electrode before the left one seems to improve the CRT performance for the non-fibrotic cases. Last, we found that the CRT performance seems to improve by positioning the right electrode halfway between the base and the apex. This work is on the line of computational works for the study of CRT and introduces new features in the field, such as the presence of the epicardial veins and the movement of the right electrode. All these studies from the different research groups can in future synergistically flow together in the development of a tool which clinicians could use during the procedure to have quantitative information about the patient’s propagation in different scenarios.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"1977 - 2004"},"PeriodicalIF":3.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01878-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142078723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive numerical approach to coil placement in cerebral aneurysms: mathematical modeling and in silico occlusion classification","authors":"Fabian Holzberger,&nbsp;Markus Muhr,&nbsp;Barbara Wohlmuth","doi":"10.1007/s10237-024-01882-y","DOIUrl":"10.1007/s10237-024-01882-y","url":null,"abstract":"<div><p>Endovascular coil embolization is one of the primary treatment techniques for cerebral aneurysms. Although it is a well-established and minimally invasive method, it bears the risk of suboptimal coil placement which can lead to incomplete occlusion of the aneurysm possibly causing recurrence. One of the key features of coils is that they have an imprinted natural shape supporting the fixation within the aneurysm. For the spatial discretization, our mathematical coil model is based on the discrete elastic rod model which results in a dimension-reduced 1D system of differential equations. We include bending and twisting responses to account for the coils natural curvature and allow for the placement of several coils having different material parameters. Collisions between coil segments and the aneurysm wall are handled by an efficient contact algorithm that relies on an octree based collision detection. In time, we use a standard symplectic semi-implicit Euler time stepping method. Our model can be easily incorporated into blood flow simulations of embolized aneurysms. In order to differentiate optimal from suboptimal placements, we employ a suitable in silico Raymond–Roy-type occlusion classification and measure the local packing density in the aneurysm at its neck, wall region and core. We investigate the impact of uncertainties in the coil parameters and embolization procedure. To this end, we vary the position and the angle of insertion of the micro-catheter, and approximate the local packing density distributions by evaluating sample statistics.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"2063 - 2089"},"PeriodicalIF":3.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01882-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142003295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tensile properties of glaucomatous human sclera, optic nerve, and optic nerve sheath","authors":"Joseph Park,&nbsp;Immi Lee,&nbsp;Somaye Jafari,&nbsp;Joseph L. Demer","doi":"10.1007/s10237-024-01872-0","DOIUrl":"10.1007/s10237-024-01872-0","url":null,"abstract":"<div><p>We characterized the tensile behavior of sclera, optic nerve (ON), and ON sheath in eyes from donors with glaucoma, for comparison with published data without glaucoma. Twelve freshly harvested eyes were obtained from donors with history of glaucoma, of average age 86 ± 7 (standard deviation) years. Rectangular samples were taken from anterior, equatorial, posterior, and peripapillary sclera, and ON sheath, while ON was in native form and measured using calipers. Under physiological temperature and humidity, tissues were preconditioned at 5% strain before loading at 0.1 mm/s. Force–displacement data were converted into engineering stress–strain curves fit by reduced polynomial hyperelastic models and analyzed by tangent moduli at 3% and 7% strain. Data were compared with an age-matched sample of 7 published control eyes. Optic atrophy was supported by significant reduction in ON cross section to 73% of normal in glaucomatous eyes. Glaucomatous was significantly stiffer than control in equatorial and peripapillary regions (<i>P</i> &lt; 0.001). However, glaucomatous ON and sheath were significantly less stiff than control, particularly at low strain (<i>P</i> &lt; 0.001). Hyperelastic models were well fit to stress–strain data (<i>R</i>² &gt; 0.997). Tangent moduli had variability similar to control in most regions, but was abnormally large in peripapillary sclera. Tensile properties were varied independently among various regions of the same eyes. Glaucomatous sclera is abnormally stiff, but the ON and sheath are abnormally compliant. These abnormalities correspond to properties predicted by finite element analysis to transfer potentially pathologic stress to the vulnerable disk and lamina cribrosa region during adduction eye movement.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"1851 - 1862"},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01872-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141900483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of cardiac patch alignment on restoring post-infarct ventricular function","authors":"Koen L. P. M. Janssens,&nbsp;Peter H. M. Bovendeerd","doi":"10.1007/s10237-024-01877-9","DOIUrl":"10.1007/s10237-024-01877-9","url":null,"abstract":"<div><p>Acute myocardial infarction (MI) leads to a loss of cardiac function which, following adverse ventricular remodeling (AVR), can ultimately result in heart failure. Tissue-engineered contractile patches placed over the infarct offer potential for restoring cardiac function and reducing AVR. In this computational study, we investigate how improvement of pump function depends on the orientation of the cardiac patch and the fibers therein relative to the left ventricle (LV). Additionally, we examine how model outcome depends on the choice of material properties for healthy and infarct tissue. In a finite element model of LV mechanics, an infarction was induced by eliminating active stress generation and increasing passive tissue stiffness in a region comprising 15% of the LV wall volume. The cardiac patch was modeled as a rectangular piece of healthy myocardium with a volume of 25% of the infarcted tissue. The orientation of the patch was varied from 0 to <span>(150^ circ )</span> relative to the circumferential plane. The infarct reduced stroke work by 34% compared to the healthy heart. Optimal patch support was achieved when the patch was oriented parallel to the subepicardial fiber direction, restoring 9% of lost functionality. Typically, about one-third of the total recovery was attributed to the patch, while the remainder resulted from restored functionality in native myocardium adjacent to the infarct. The patch contributes to cardiac function through two mechanisms. A contribution of tissue in the patch and an increased contribution of native tissue, due to favorable changes in mechanical boundary conditions.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"1963 - 1976"},"PeriodicalIF":3.0,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01877-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141858695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are aortic biomechanical properties early markers of dilatation in patients with Marfan syndrome? A systematic review and meta-analysis","authors":"Claire Rosnel,&nbsp;Raphael Sivera,&nbsp;Elena Cervi,&nbsp;Mark Danton,&nbsp;Silvia Schievano,&nbsp;Claudio Capelli,&nbsp;Ankush Aggarwal","doi":"10.1007/s10237-024-01881-z","DOIUrl":"10.1007/s10237-024-01881-z","url":null,"abstract":"<div><p>Although tissue stiffness is known to play an important role in aortic dilatation, the current guidelines for offering preventative surgery in patients with Marfan syndrome rely solely on the aortic diameter. In this systematic review and meta-analysis, we analyze and compare literature on in vivo aortic stiffness measures in Marfan patients. Our aim is to assess the potential of these measurements as early indicators of aortic dilatation. Following the PRISMA guidelines, we collected literature on diameter and three in vivo stiffness measures: Pulse wave velocity (PWV), <span>(beta )</span>-stiffness index (SI) and distensibility, at five different aortic locations in patients with Marfan syndrome. Results were reviewed and compared against each other. For meta-analysis, an augmented dataset was created by combining data from the literature. Regression with respect to age and statistical comparisons were performed. Thirty articles reporting data from 1925 patients with Marfan and 836 patients without Marfan were reviewed. PWV was found to be higher in Marfan, but only in dilated aortas. Distensibility was found to be lower even in non-dilated aortas, and its decrease was associated with higher chances of developing aortic dilatation. <span>(beta )</span>-SI was higher in Marfan patients and was positively correlated with the rate of aortic dilatation, emphasizing its role as a valuable indicator. In our meta-analysis, all stiffness measures showed a significant variation with age. Distensibility and <span>(beta )</span>-stiffness index were different in Marfan patients at all locations, and the difference was more pronounced after accounting for age-related variation. From the literature, <span>(beta )</span>-SI and distensibility emerge as the best predictors of future aortic dilatation. Our meta-analysis quantifies age-related changes in aortic stiffness and highlights the importance of accounting for age in comparing these measurements. Missing diameter values in the literature limited our analysis. Further investigation of criteria combining stiffness and diameter is recommended to better assist clinical decisions for prophylactic surgery.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"2043 - 2061"},"PeriodicalIF":3.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01881-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141786976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient uncertainty quantification in a spatially multiscale model of pulmonary arterial and venous hemodynamics","authors":"M. J. Colebank,&nbsp;N. C. Chesler","doi":"10.1007/s10237-024-01875-x","DOIUrl":"10.1007/s10237-024-01875-x","url":null,"abstract":"<div><p>Pulmonary hypertension (PH) is a debilitating disease that alters the structure and function of both the proximal and distal pulmonary vasculature. This alters pressure-flow relationships in the pulmonary arterial and venous trees, though there is a critical knowledge gap in the relationships between proximal and distal hemodynamics in disease. Multiscale computational models enable simulations in both the proximal and distal vasculature. However, model inputs and measured data are inherently uncertain, requiring a full analysis of the sensitivity and uncertainty of the model. Thus, this study quantifies model sensitivity and output uncertainty in a spatially multiscale, pulse-wave propagation model of pulmonary hemodynamics. The model includes fifteen proximal arteries and twelve proximal veins, connected by a two-sided, structured tree model of the distal vasculature. We use polynomial chaos expansions to expedite sensitivity and uncertainty quantification analyses and provide results for both the proximal and distal vasculature. We quantify uncertainty in blood pressure, blood flow rate, wave intensity, wall shear stress, and cyclic stretch. The latter two are important stimuli for endothelial cell mechanotransduction. We conclude that, while nearly all the parameters in our system have some influence on model predictions, the parameters describing the density of the microvascular beds have the largest effects on all simulated quantities in both the proximal and distal arterial and venous circulations.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"1909 - 1931"},"PeriodicalIF":3.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01875-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141786977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanobiological optimization of scaffolds for bone tissue engineering","authors":"Timothy O. Josephson,&nbsp;Elise F. Morgan","doi":"10.1007/s10237-024-01880-0","DOIUrl":"10.1007/s10237-024-01880-0","url":null,"abstract":"<div><p>Synthetic bone graft scaffolds aim to generate new bone tissue and alleviate the limitations of autografts and allografts. To meet that aim, it is essential to have a design approach able to generate scaffold architectures that will promote bone formation. Here, we present a topology-varying design optimization method, the “mixed-topology” approach, that generates new designs from a set of starting structures. This approach was used with objective functions focusing on improving the scaffold’s local mechanical microenvironments to mechanobiologically promote bone formation within the scaffold and constraints to ensure manufacturability and achieve desired macroscale properties. The results demonstrate that this approach can successfully generate scaffold designs with improved microenvironments, taking into account different combinations of relevant stimuli and constraints.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 6","pages":"2025 - 2042"},"PeriodicalIF":3.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141764766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"HepG2 cells undergo regulatory volume decrease by mechanically induced efflux of water and solutes","authors":"Dominic J. Olver,&nbsp;Iqra Azam,&nbsp;James D. Benson","doi":"10.1007/s10237-024-01868-w","DOIUrl":"10.1007/s10237-024-01868-w","url":null,"abstract":"<div><p>This study challenges the conventional belief that animal cell membranes lack a significant hydrostatic gradient, particularly under anisotonic conditions, as demonstrated in the human hepatoma cell line HepG2. The Boyle van’t Hoff (BvH) relation describes volumetric equilibration to anisotonic conditions for many cells. However, the BvH relation is simple and does not include many cellular components such as the cytoskeleton and actin cortex, mechanosensitive channels, and ion pumps. Here we present alternative models that account for mechanical resistance to volumetric expansion, solute leakage, and active ion pumping. We found the BvH relation works well to describe hypertonic volume equilibration but not hypotonic volume equilibration. After anisotonic exposure and return isotonic conditions cell volumes were smaller than their initial isotonic volume, indicating solutes had leaked out of the cell during swelling. Finally, we observed HepG2 cells undergo regulatory volume decrease at both 20 °C and 4 °C, indicating regulatory volume decrease to be a relatively passive phenomenon and not driven by ion pumps. We determined the turgor-leak model, which accounts for mechanical resistance and solute leakage, best fits the observations found in the suite of experiments performed, while other models were rejected.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 5","pages":"1781 - 1799"},"PeriodicalIF":3.0,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141618869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of sagittal alignment on spinal cord biomechanics in the stenotic cervical spine during neck flexion and extension","authors":"Shalini Gundamraj,&nbsp;Karthik Banurekha Devaraj,&nbsp;Balaji Harinathan,&nbsp;Anjishnu Banerjee,&nbsp;Narayan Yoganandan,&nbsp;Aditya Vedantam","doi":"10.1007/s10237-024-01866-y","DOIUrl":"10.1007/s10237-024-01866-y","url":null,"abstract":"<div><p>Spinal cord stress and strain contribute to degenerative cervical myelopathy (DCM), while cervical kyphosis is known to negatively impact surgical outcomes. In DCM, the relationship between spinal cord biomechanics, sagittal alignment, and cord compression is not well understood. Quantifying this relationship can guide surgical strategies. A previously validated three-dimensional finite element model of the human cervical spine with spinal cord was used. Three models of cervical alignment were created: lordosis (C2–C7 Cobb angle: 20°), straight (0°), and kyphosis (− 9°). C5–C6 spinal stenosis was simulated with ventral disk protrusions, reducing spinal canal diameters to 10 mm, 8 mm, and 6 mm. Spinal cord pre-stress and pre-strain due to alignment and compression were quantified. Cervical flexion and extension were simulated with a pure moment load of 2 Nm. The Von Mises stress and maximum principal strain of the whole spinal cord were calculated during neck motion and the relationship between spinal cord biomechanics, alignment, and compression was analyzed using linear regression analysis. Spinal cord pre-stress and pre-strain were greatest with kyphosis (7.53 kPa, 5.4%). Progressive kyphosis and stenosis were associated with an increase in spinal cord stress (<i>R</i>² = 0.99) and strain (<i>R</i>² = 0.99). Cervical kyphosis was associated with greater spinal cord stress and strain during neck flexion–extension and the magnitude of difference increased with increasing stenosis. Cervical kyphosis increases baseline spinal cord stress and strain. Incorporating sagittal alignment with compression to calculate spinal cord biomechanics is necessary to accurately quantify spinal stress and strain during neck flexion and extension.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"23 5","pages":"1757 - 1764"},"PeriodicalIF":3.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141603142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}