Biomechanics and Modeling in Mechanobiology最新文献

{"title":"Predicting fall parameters from infant skull fractures using machine learning","authors":"Jacob N. Hirst,&nbsp;Brian R. Phung,&nbsp;Bjorn T. Johnsson,&nbsp;Junyan He,&nbsp;Brittany Coats,&nbsp;Ashley D. Spear","doi":"10.1007/s10237-024-01922-7","DOIUrl":"10.1007/s10237-024-01922-7","url":null,"abstract":"<div><p>When infants are admitted to the hospital with skull fractures, providers must distinguish between cases of accidental and abusive head trauma. Limited information about the incident is available in such cases, and witness statements are not always reliable. In this study, we introduce a novel, data-driven approach to predict fall parameters that lead to skull fractures in infants in order to aid in determinations of abusive head trauma. We utilize a state-of-the-art finite element fracture simulation framework to generate a unique dataset of skull fracture patterns from simulated falls. We then extract features from the resulting fracture patterns in this dataset to be used as input into machine learning models. We compare seven machine learning models on their abilities to predict two fall parameters: impact site and fall height. The results from our best-performing models demonstrate that while predicting the exact fall height remains challenging (<span>(R^2)</span> 0.27 for the ridge regression model), we can effectively identify potential impact sites (<span>(R^2)</span> between 0.65 and 0.76 for the random forest regression model). This work not only provides a tool to enhance the ability to assess abuse in cases of pediatric head trauma, but also advocates for advancements in computational models to simulate complex skull fractures.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"521 - 537"},"PeriodicalIF":3.0,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142998081","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":"On the Gaussian modulus of lipid membranes","authors":"Ashutosh Agrawal","doi":"10.1007/s10237-025-01925-y","DOIUrl":"10.1007/s10237-025-01925-y","url":null,"abstract":"<div><p>The Gaussian modulus is a crucial property that influences topological transformations in lipid membranes. However, unlike the bending modulus, estimating the Gaussian modulus has been particularly challenging due to the constraints imposed by the Gauss-Bonnet theorem. Despite this, various theoretical, computational, and experimental approaches have been developed to estimate the Gaussian modulus, though they are often complex, and analytical estimates remain rare. In this work, we present a minimalist model inspired by the folding of a sheet of paper, which provides an exact calculation of the Gaussian modulus. Remarkably, the induced deformation does not affect the Gaussian curvature or alter the system’s topology, yet it yields the modulus that governs these geometric properties.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"553 - 557"},"PeriodicalIF":3.0,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142982326","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":"Actin instability alters red blood cell mechanics and Piezo1 channel activity","authors":"Nicoletta Braidotti,&nbsp;Davide Rizzo,&nbsp;Catalin D. Ciubotaru,&nbsp;Giuseppina Sacco,&nbsp;Annalisa Bernareggi,&nbsp;Dan Cojoc","doi":"10.1007/s10237-024-01921-8","DOIUrl":"10.1007/s10237-024-01921-8","url":null,"abstract":"<div><p>The organization and dynamics of the spectrin–actin membrane cytoskeleton play a crucial role in determining the mechanical properties of red blood cells (RBC). RBC are subjected to various forces that induce deformation during blood microcirculation. Such forces also regulate membrane tension, leading to Piezo1 channel activation, which is functionally linked to RBC dehydration through calcium influx and subsequent activation of Gardos channels, ultimately resulting in variations in RBC volume. In this study, we investigated how actin instability affects Piezo1 channel gating, in relation to RBC deformation and mechanical properties, using micropipette aspiration and optical tweezers. Actin instability, induced by 0.5 μM Cytochalasin-D (Cyt-D), led to a 22% reduction in the activation pressure. Additionally, we observed a decreasing trend in Young’s modulus, membrane tension, and viscosity. By measuring the time required for cell shape recovery after deformation in an optical trap, we found that Cyt-D-treated RBC took approximately 14% longer to recover compared to untreated cells. The bimodal imaging feature of our experimental approach allowed us to simultaneously measure and correlate activation pressure with mechanical properties at the single-cell level. A significant correlation was found between these parameters in both treated and untreated RBC. Our findings demonstrate the influence of actin instability on both Piezo1 activation and RBC mechanics. These results offer new insights into the interplay between F-actin and Piezo1 in RBC mechanobiology.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"507 - 520"},"PeriodicalIF":3.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941914","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":"Fluid–structure–growth modeling in ascending aortic aneurysm: capability to reproduce a patient case","authors":"Kexin Yan,&nbsp;Wenfeng Ye,&nbsp;Antonio Martínez,&nbsp;Leonardo Geronzi,&nbsp;Pierre Escrig,&nbsp;Jacques Tomasi,&nbsp;Michel Rochette,&nbsp;Pascal Haigron,&nbsp;Aline Bel-Brunon","doi":"10.1007/s10237-024-01915-6","DOIUrl":"10.1007/s10237-024-01915-6","url":null,"abstract":"<div><p>Predicting the evolution of ascending aortic aneurysm (AscAA) growth is a challenge, complicated by the intricate interplay of aortic geometry, tissue behavior, and blood flow dynamics. We investigate a flow-structural growth and remodeling (FSG) model based on the homogenized constrained mixture theory to simulate realistic AscAA growth evolution. Our approach involves initiating a finite element model with an initial elastin insult, driven by the distribution of Time-Averaged Wall Shear Stress (TAWSS) derived from computational fluid dynamics simulations. Through FSG simulation, we first calibrate the growth and remodeling material parameters to reproduce the growth observed on a patient-specific case. Then, we explore the influence of two critical parameters: the direction of the inlet jet flow, which affects the zone of significant TAWSS, and prestretch, which impacts the tissue homeostatic state. Our results show that calibrating material parameters, inlet flow direction, and prestretch allows to reproduce the observed growth, and that prestretch calibration and inlet flow direction significantly influence the simulated growth pattern. Our workflow can be applied to additional patient cases to confirm these tendencies and progress toward a predictive tool for clinical decision support.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"405 - 422"},"PeriodicalIF":3.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142930395","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":"Modeling bladder mechanics with 4D reconstruction of murine ex vivo bladder filling","authors":"Eli Broemer,&nbsp;Pragya Saxena,&nbsp;Sarah Bartolone,&nbsp;Grant Hennig,&nbsp;Gerald M. Herrera,&nbsp;Bernadette Zwaans,&nbsp;Nathan R. Tykocki,&nbsp;Sara Roccabianca","doi":"10.1007/s10237-024-01914-7","DOIUrl":"10.1007/s10237-024-01914-7","url":null,"abstract":"<div><p>This study presents a novel methodology for high-resolution 3D bladder modeling during filling, developed by leveraging improved imaging and computational techniques. Using murine bladder filling data, the methodology generates accurate 3D geometries across time, enabling in-depth mechanical analysis. Comparison with a traditional spherical model revealed similar stress trends, but the 3D model permitted nuanced quantifications, such as localized surface curvature and stress analysis. This advanced 3D model captures complex tissue behavior crucially influenced by tissue-specific microstructural characteristics. This methodology can also be extended to other tissues such as lungs, uterus, and gastrointestinal tract tissues. Applying this analysis to different tissues can uncover mechanisms driven by localized mechanics, such as the sensation of fullness in the bladder due to microcontractions, uterine contractions during labor, and peristaltic contractions in the gastrointestinal tract. This broader applicability underscores our approach’s potential to advance the understanding of tissue-specific mechanical behaviors across various biological systems.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 1","pages":"347 - 359"},"PeriodicalIF":3.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142908681","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":"Stress relaxation rates of myocardium from failing and non-failing hearts","authors":"Marissa Gionet-Gonzales,&nbsp;Gianna Gathman,&nbsp;Jonah Rosas,&nbsp;Kyle Y. Kunisaki,&nbsp;Dominique Gabriele P. Inocencio,&nbsp;Niki Hakami,&nbsp;Gregory N. Milburn,&nbsp;Angela A. Pitenis,&nbsp;Kenneth S. Campbell,&nbsp;Beth L. Pruitt,&nbsp;Ryan S. Stowers","doi":"10.1007/s10237-024-01909-4","DOIUrl":"10.1007/s10237-024-01909-4","url":null,"abstract":"<div><p>The heart is a dynamic pump whose function is influenced by its mechanical properties. The viscoelastic properties of the heart, i.e., its ability to exhibit both elastic and viscous characteristics upon deformation, influence cardiac function. Viscoelastic properties change during heart failure (HF), but direct measurements of failing and non-failing myocardial tissue stress relaxation under constant displacement are lacking. Further, how consequences of tissue remodeling, such as fibrosis and fat accumulation, alter the stress relaxation remains unknown. To address this gap, we conducted stress relaxation tests on porcine myocardial tissue to establish baseline properties of cardiac tissue. We found porcine myocardial tissue to be fast relaxing, characterized by stress relaxation tests on both a rheometer and microindenter. We then measured human left ventricle (LV) epicardium and endocardium tissue from non-failing, ischemic HF and non-ischemic HF patients by microindentation. Analyzing by patient groups, we found that ischemic HF samples had slower stress relaxation than non-failing endocardium. Categorizing the data by stress relaxation times, we found that slower stress relaxing tissues were correlated with increased collagen deposition and increased α-smooth muscle actin (α-SMA) stress fibers, a marker of fibrosis and cardiac fibroblast activation, respectively. In the epicardium, analyzing by patient groups, we found that ischemic HF had faster stress relaxation than non-ischemic HF and non-failing. When categorizing by stress relaxation times, we found that faster stress relaxation correlated with Oil Red O staining, a marker for adipose tissue. These data show that changes in stress relaxation vary across the different layers of the heart during ischemic versus non-ischemic HF. These findings reveal how the viscoelasticity of the heart changes, which will lead to better modeling of cardiac mechanics for in vitro and in silico HF models.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 1","pages":"265 - 280"},"PeriodicalIF":3.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01909-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142908779","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":"Region-specific biomechanical characterization of ascending thoracic aortic aneurysm of hypertensive patients with bicuspid aortic valves","authors":"Xiaojuan Xu,&nbsp;Fan Yang,&nbsp;Yue Yu,&nbsp;Yuan-Feng Xin,&nbsp;Jianhua Tong","doi":"10.1007/s10237-024-01917-4","DOIUrl":"10.1007/s10237-024-01917-4","url":null,"abstract":"<div><p>Hypertension and bicuspid aortic valve (BAV) are key clinical factors that may affect local biomechanical properties of ascending thoracic aortic aneurysms (ATAAs). This study sought to investigate regional differences in biaxial mechanical properties of the ATAAs for the hypertensive patients with BAV. Fresh ATAA samples were harvested from 16 hypertensive patients (age, 66 ± 9 years) undergoing elective aortic surgery. Biaxial extension tests were employed to characterize region-specific biaxial mechanical behaviors of the hypertensive BAV-ATAAs. A material model was used to fit biaxial experimental data to obtain model parameters in different regions. Histological analysis was performed to investigate the underlying aortic microstructure and to determine percentages of elastic and collagen fibers. Mechanical behaviors of the hypertensive BAV-ATAAs were nonlinear and anisotropic for most specimens from anterior, lateral and posterior regions. Under the equibiaxial stresses, the ATAA tissues in the lateral region had significantly lower extensibility and significantly higher stiffness in both circumferential and longitudinal directions when compared with the posterior and medial regions. The material model was able to fit regional biaxial data well. Histology showed that laminar structures of elastic fibers were mainly disrupted in the anterior and lateral regions in which, however, pronounced collagen fiber hyperplasia was observed. Moreover, there was a strong positive correlation between circumferential aortic stiffness and patient age in the anterior and lateral regions. Our results suggest that elastic properties in the lateral and anterior regions are more deteriorated than those in the posterior and medial regions for the hypertensive BAV-ATAAs. Thus, the outer curvature of the ATAA wall should be regarded as special quadrants that may be highly susceptible to microstructural changes and may have a substantial impact on aneurysm growth.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"441 - 454"},"PeriodicalIF":3.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142890899","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":"Measuring the biomechanical properties of cell-derived fibronectin fibrils","authors":"Caleb J. Dalton,&nbsp;Soma Dhakal,&nbsp;Christopher A. Lemmon","doi":"10.1007/s10237-024-01918-3","DOIUrl":"10.1007/s10237-024-01918-3","url":null,"abstract":"<div><p>Embryonic development, wound healing, and organogenesis all require assembly of the extracellular matrix protein fibronectin (FN) into insoluble, viscoelastic fibrils. FN fibrils mediate cell migration, force generation, angiogenic sprouting, and collagen deposition. While the critical role of FN fibrils has long been appreciated, we still have an extremely poor understanding of their mechanical properties and how these mechanical properties facilitate cellular responses. Here, we demonstrate the development of a system to probe the mechanics of cell-derived FN fibrils and present quantified mechanical properties of these fibrils. We demonstrate that: fibril elasticity can be classified into three phenotypes: linearly elastic, strain-hardening, or nonlinear with a “toe” region; fibrils exhibit pre-conditioning, with nonlinear “toe” fibrils becoming more linear with repeated stretch and strain-hardened fibrils becoming less linear with repeated stretch; fibrils exhibit an average elastic modulus of roughly 8 MPa; and fibrils exhibit a time-dependent viscoelastic behavior, exhibiting a transition from a stress relaxation response to an inverse stress relaxation response. These findings have a potentially significant impact on our understanding of cellular mechanical responses in fibrotic diseases and embryonic development, where FN fibrils play a major role.\u0000</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"455 - 469"},"PeriodicalIF":3.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10237-024-01918-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142890938","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":"Noninvasive estimation of central blood pressure through fluid–structure interaction modeling","authors":"Peishuo Wu,&nbsp;Chi Zhu","doi":"10.1007/s10237-024-01916-5","DOIUrl":"10.1007/s10237-024-01916-5","url":null,"abstract":"<div><p>Central blood pressure (cBP) is considered a superior indicator of cardiovascular fitness than brachial blood pressure (bBP). Even though bBP is easy to measure noninvasively, it is usually higher than cBP due to pulse wave amplification, characterized by the gradual increase in peak systolic pressure during pulse wave propagation. In this study, we aim to develop an individualized transfer function that can accurately estimate cBP from bBP. We first construct a three-dimensional, patient-specific model of the upper limb arterial system using fluid–structure interaction simulations, incorporating variable material properties and complex boundary conditions. Then, we develop an analytical brachial-aortic transfer function based on novel solutions for compliant vessels. The accuracy of this transfer function is successfully validated against numerical simulation results, which effectively reproduce pulse wave propagation and amplification, with key hemodynamic parameters falling within the range of clinical measurements. Further analysis of the transfer function reveals that cBP is a linear combination of bBP and aortic flow rate in the frequency domain, with the coefficients determined by vessel geometry, material properties, and boundary conditions. Additionally, bBP primarily contributes to the steady component of cBP, while the aortic flow rate is responsible for the pulsatile component. Furthermore, local sensitivity analysis indicates that the lumen radius is the most influential parameter in accurately estimating cBP. Although not directly applicable clinically, the proposed transfer function enhances understanding of the underlying physics—highlighting the importance of aortic flow and lumen radius—and can guide the development of more practical transfer functions.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 2","pages":"423 - 439"},"PeriodicalIF":3.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862875","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":"Full-field, frequency-domain comparison of simulated and measured human brain deformation","authors":"Amir H. G. Arani,&nbsp;Ruth J. Okamoto,&nbsp;Jordan D. Escarcega,&nbsp;Antoine Jerusalem,&nbsp;Ahmed A. Alshareef,&nbsp;Philip V. Bayly","doi":"10.1007/s10237-024-01913-8","DOIUrl":"10.1007/s10237-024-01913-8","url":null,"abstract":"<div><p>We propose a robust framework for quantitatively comparing model-predicted and experimentally measured strain fields in the human brain during harmonic skull motion. Traumatic brain injuries (TBIs) are typically caused by skull impact or acceleration, but how skull motion leads to brain deformation and consequent neural injury remains unclear and comparison of model predictions to experimental data remains limited. Magnetic resonance elastography (MRE) provides high-resolution, full-field measurements of dynamic brain deformation induced by harmonic skull motion. In the proposed framework, full-field strain measurements from human brain MRE in vivo are compared to simulated strain fields from models with similar harmonic loading. To enable comparison, the model geometry and subject anatomy, and subsequently, the predicted and measured strain fields are nonlinearly registered to the same standard brain atlas. Strain field correlations (<span>({C}_{v})</span>), both global (over the brain volume) and local (over smaller sub-volumes), are then computed from the inner product of the complex-valued strain tensors from model and experiment at each voxel. To demonstrate our approach, we compare strain fields from MRE in six human subjects to predictions from two previously developed models. Notably, global <span>({C}_{v})</span> values are higher when comparing strain fields from different subjects (<span>({C}_{v})</span>~0.6–0.7) than when comparing strain fields from either of the two models to strain fields in any subject. The proposed framework provides a quantitative method to assess similarity (and to identify discrepancies) between model predictions and experimental measurements of brain deformation and thus can aid in the development and evaluation of improved models of brain biomechanics.</p></div>","PeriodicalId":489,"journal":{"name":"Biomechanics and Modeling in Mechanobiology","volume":"24 1","pages":"331 - 346"},"PeriodicalIF":3.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862874","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}