Networks behind the morphology and structural design of living systems

Physics of Life Reviews, Journal Year: 2022, Volume and Issue: 41, P. 1 - 21

Published: March 10, 2022

Technological advances in imaging techniques and biometric data acquisition have enabled us to apply methods of network science study the morphology structural design organelles, organs, tissues, as well coordinated interactions among them that yield a healthy physiology at level whole organisms. We here review research dedicated these advances, particular focusing on networks between cells, topology multicellular structures, neural interactions, fluid transportation networks, anatomical networks. The percolation blood vessels, connectivity within brain, porous structure bones, relations different parts human body are just some examples we explore detail. argue show models, methods, algorithms developed realm ushering new era network-based inquiry into living systems broadest possible terms. also emphasize need applicability this is likely increase significantly years come due rapid progress made development bioartificial substitutes tissue engineering.

Language: Английский

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Risk Factors, Pathophysiologic Mechanisms, and Potential Treatment Strategies of Futile Recanalization after Endovascular Therapy in Acute Ischemic Stroke

Aging and Disease, Journal Year: 2023, Volume and Issue: 14(6), P. 2096 - 2096

Published: Jan. 1, 2023

Endovascular therapy is the first-line treatment for acute ischemic stroke. However, studies have shown that, even with timely opening of occluded blood vessels, nearly half all patients treated endovascular stroke still poor functional recovery, a phenomenon called “futile recanalization.”. The pathophysiology futile recanalization complex and may include tissue no-reflow (microcirculation reperfusion failure despite large artery), early arterial reocclusion (reocclusion recanalized artery 24-48 hours post therapy), collateral circulation, hemorrhagic transformation (cerebral bleeding following primary stroke), impaired cerebrovascular autoregulation, hypoperfusion volume. Therapeutic strategies targeting these mechanisms been attempted in preclinical research; however, translation to bedside remains be explored. This review summarizes risk factors, pathophysiological mechanisms, targeted recanalization, focusing on deepen understanding this provide new translational research ideas potential intervention targets improving efficacy

Language: Английский

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Stokes flows in a two-dimensional bifurcation

Royal Society Open Science, Journal Year: 2025, Volume and Issue: 12(1)

Published: Jan. 1, 2025

The flow network model is an established approach to approximate pressure–flow relationships in a bifurcating network, and has been widely used many contexts. Existing models typically assume unidirectional exploit Poiseuille’s law, thus neglect the impact of bifurcation geometry finite-sized objects on flow. We determine by computing Stokes flows two-dimensional (2D) using Lightning-AAA Rational algorithm, novel mesh-free algorithm for solving 2D problems utilizing applied complex analysis based rational approximation Goursat functions. compute conductances bifurcations with different channel widths, angles, curved boundary geometries fixed circular objects. quantify difference between computed their Poiseuille law approximations demonstrate importance incorporating detailed into existing models. parametrize as functions dimensionless parameters object machine learning approach, which simple use provides more accurate than law. Finally, details are presented.

Language: Английский

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Modelling midline shift and ventricle collapse in cerebral oedema following acute ischaemic stroke

PLoS Computational Biology, Journal Year: 2024, Volume and Issue: 20(5), P. e1012145 - e1012145

Published: May 28, 2024

In ischaemic stroke, a large reduction in blood supply can lead to the breakdown of blood-brain barrier and cerebral oedema after reperfusion therapy. The resulting fluid accumulation brain may contribute significant rise intracranial pressure (ICP) tissue deformation. Changes level ICP are essential for clinical decision-making therapeutic strategies. However, measurement is constrained by techniques obtaining exact values has proven challenging. this study, we propose first computational model simulation following acute stroke investigation midline shift (MLS) relationship. consists three components healthy flow, occluded flow oedema, respectively. utilized obtain core geometry then imported into growth. results compared with data from 97 traumatic injury patients validation major parameters. Midline been widely used diagnosis, decision-making, prognosis patients. Therefore, focus on quantifying relationship between identify factors that affect ICP-MLS Three investigated, including geometry, damage severity types (including rare oedema). Meanwhile, two (stress tension/compression) mechanical also presented differences stress, tension, compression intraparenchymal periventricular regions discussed. This work helps predict precisely therefore provides improved guidance treatment oedema.

Language: Английский

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On the Sensitivity Analysis of Porous Finite Element Models for Cerebral Perfusion Estimation

Annals of Biomedical Engineering, Journal Year: 2021, Volume and Issue: 49(12), P. 3647 - 3665

Published: June 21, 2021

Computational physiological models are promising tools to enhance the design of clinical trials and assist in decision making. Organ-scale haemodynamic gaining popularity evaluate perfusion a virtual environment both healthy diseased patients. Recently, principles verification, validation, uncertainty quantification such have been laid down ensure safe applications engineering software medical device industry. The present study sets out establish guidelines for usage three-dimensional steady state porous cerebral model human brain following detailed verification validation (V&V 40) standard American Society Mechanical Engineers. relies on finite element method has developed specifically estimate how is altered ischaemic stroke patients before, during, after treatments. Simulations compared with exact analytical solutions thorough sensitivity analysis presented covering every numerical parameter. results suggest that can approximate blood pressure distributions reliably even coarse grid first order elements. On other hand, higher elements essential mitigate errors volumetric flow rate estimation through cortical surface regions. Matching corresponding major arteries identified as milestone. It found inlet velocity boundary conditions hard obtain constant feasible alternatives. A one-dimensional which serve computationally inexpensive replacement ease parameter optimisation, analyses quantification. findings be generalised organ-scale models. increase applicability computational regarding treatment development cerebrovascular conditions.

Language: Английский

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In silico trials for treatment of acute ischemic stroke: Design and implementation

Computers in Biology and Medicine, Journal Year: 2021, Volume and Issue: 137, P. 104802 - 104802

Published: Aug. 26, 2021

An in silico trial simulates a disease and its corresponding therapies on cohort of virtual patients to support the development evaluation medical devices, drugs, treatment. In trials have potential refine, reduce cost, partially replace current vivo studies, namely clinical animal testing. We present design implementation an for treatment acute ischemic stroke. propose event-based modelling approach simulation injury, where changes state system (the events) are assumed be instantaneous. Using this we able combine diverse set models, spanning multiple time scales, model stroke, treatment, resulting brain tissue injury. The is designed modular aid reproducibility. It provides comprehensive framework application any trial. A statistical population used generate cohorts patients. Patient functional outcomes also predicted with model, using injury results patient's parameters. demonstrate functionality by running proof concept trials. simulate same twice: once successful (successful recanalisation) unsuccessful (unsuccessful treatment). Ways overcome some challenges difficulties setting up such discussed, as validation computational limitations.

Language: Английский

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Quantification of hypoxic regions distant from occlusions in cerebral penetrating arteriole trees

PLoS Computational Biology, Journal Year: 2022, Volume and Issue: 18(8), P. e1010166 - e1010166

Published: Aug. 5, 2022

The microvasculature plays a key role in oxygen transport the mammalian brain. Despite close coupling between cerebral vascular geometry and local demand, recent experiments have reported that microvascular occlusions can lead to unexpected distant tissue hypoxia infarction. To better understand spatial correlation hypoxic regions occlusion sites, we used both vivo silico simulations investigate effects of penetrating arteriole trees on hypoxia. In rat model microembolisation, 25 μm microspheres were injected through carotid artery occlude arterioles. representative models human cortical columns, arterioles occluded by simulating same size was simulated using Green’s function method. locations segmented, two novel distance analyses implemented study their correlation. found be present simulations, mainly due hypoperfusion region downstream site. Furthermore, reasonable agreement for sites is shown which indicates good applicability understanding response blood flow microemboli.

Language: Английский

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Modelling the effects of cerebral microthrombi on tissue oxygenation and cell death

Journal of Biomechanics, Journal Year: 2021, Volume and Issue: 127, P. 110705 - 110705

Published: Aug. 23, 2021

Language: Английский

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Review of in silico models of cerebral blood flow in health and pathology

Progress in Biomedical Engineering, Journal Year: 2023, Volume and Issue: 5(2), P. 022003 - 022003

Published: April 1, 2023

Abstract In this review, we provide a summary of the state-of-the-art in silico modelling cerebral blood flow (CBF) and its application clinical trials. CBF plays key role transport nutrients, including oxygen glucose, to brain cells, vasculature is highly complex, multi-scale, dynamic system that acts ensure supply demand these nutrients are continuously balanced. It also other substances, such as recombinant tissue-plasminogen activator, tissue. Any dysfunction can rapidly lead cell death permanent damage regions, leading loss bodily functions death. The complexity difficulty obtaining accurate anatomical information combine make mathematical models understanding supply, diagnosis cerebrovascular disease, quantification effects thrombi, selection optimum intervention, neurosurgical planning. Similar have now been widely applied variety body organs (most notably heart), but still far behind. increased availability experimental data last 15 years however has enabled develop more progress focus review. We thus present brief review foundations underpin both microvasculature macrovasculature. demonstrate how be context diseases show work recently expanded trials for first time. Most date performed ischaemic stroke or aneurysms, in-silico many applications neurodegenerative where vital play testing hypotheses providing test beds interventions.

Language: Английский

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MRI-based parameter inference for cerebral perfusion modelling in health and ischaemic stroke

Computers in Biology and Medicine, Journal Year: 2023, Volume and Issue: 166, P. 107543 - 107543

Published: Sept. 30, 2023

Cerebral perfusion modelling is a promising tool to predict the impact of acute ischaemic stroke treatments on spatial distribution cerebral blood flow (CBF) in human brain. To estimate treatment efficacy based CBF, simulations need become suitable for group-level investigations and thus account physiological variability between individuals. However, computational date has been restricted few patient-specific cases. This study set out establish automated parameter inference neuroimaging data enable CBF groups. Magnetic resonance imaging (MRI) from 75 healthy senior adults were utilised. Brain geometries computed reference subjects' T1-weighted MRI. Haemodynamic model parameters determined maps measured by arterial spin labelling (ASL) Thereafter, conducted cases followed 150 representing an occlusion cessation left right middle arteries. The anatomical fitness brain was evaluated comparing simulated grey (GM) white matter (WM) volumes measurements subjects. Strong positive correlations found both tissue types (GM: Pearson's r 0.74, P<0.001; WM: 0.84, P<0.001). tuning verified total volumetric rate subjects (Pearson's 0.89, In cases, infarct volume using perfusion-based 197±25 ml. Computational predictions agreement with haemodynamic values literature concerning T1-weighted, T2-weighted, phase-contrast MRI scenarios did not capture small infarcts (left tail distribution), which could be explained neglected compensatory mechanisms, e.g. collaterals. proposed method provides foundation silico clinical trials assist medical device drug development.

Language: Английский

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