Cell–matrix interaction during strain-dependent remodelling of simulated collagen networks

The importance of tissue remodelling is widely accepted, but the mechanism by which the remodelling process occurs remains poorly understood. At the tissue scale, the concept of tensional homeostasis, in which there exists a target stress for a cell and remodelling functions to move the cell stress towards that target, is an important foundation for much theoretical work. We present here a theoretical model of a cell in parallel with a network to study what factors of the remodelling process help the cell move towards mechanical stability. The cell-network system was deformed and kept at constant stress. Remodelling was modelled by simulating strain-dependent degradation of collagen fibres and four different cases of collagen addition. The model did not lead to complete tensional homeostasis in the range of conditions studied, but it showed how different expressions for deposition and removal of collagen in a fibre network can interact to modulate the cell's ability to shield itself from an imposed stress by remodelling the surroundings. This study also showed how delicate the balance between deposition and removal rates is and how sensitive the remodelling process is to small changes in the remodelling rules.

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Digital Technologies – Innovative Solutions for Agriculture

Elektrotekhnologii i elektrooborudovanie v APK ◽

10.22314/2658-4859-2020-67-1-127-132 ◽

2020 ◽

Vol 67 (1) ◽

pp. 127-132

Author(s):

Marina A. Nikitina ◽

Dmitriy N. Osyanin ◽

Irina V. Petrunina

Keyword(s):

Farm Animals ◽

High Tech ◽

Mathematical Apparatus ◽

Online Mode ◽

Cell Matrix ◽

Algorithmic Support ◽

Quality Product ◽

A Cell ◽

Parametric Description ◽

Animal Feeding

High-tech decision support systems based on the knowledge of experts in the field of animal feeding and a rigorous mathematical apparatus make it possible to increase the productivity of the animals and provide a high-quality product with the ability to trace the trophological chain from the field to the counter. (Research purpose) To identify methodological approaches for the development of algorithmic support and software for assessment and optimizing the animals diet. (Materials and Methods) The authors complied a structural-parametric model of a productive animal feeding in a cell matrix form. They represented the whole variety of existing known and unknown relationships between the factors of the farm animal state and the feeding ration characteristics. It was found that when forming a feeding ration, it was necessary to assess the degree of influence on productivity of not individual indicators, but its combination. (Results and discussion) The authors considered parametric descriptions of farm animals; diet with selected groups of indicators, characteristics and properties. It was stated that the parametric description of feeding contained a set of parameters taking into account at least 25 nutritional indicators. They presented a mathematical apparatus for evaluating and optimizing the feeding ration. It was determined that the automation of the process of calculating the daily ration of an animal allowed to change the diets depending on the availability of feed in the farm and their chemical composition in real time. The authors found out that an increase in the productivity of animals and poultry by 30-50 percent was possible due to balanced full-fledged feeding. (Conclusions) The authors showed a systematic approach to the development of software for evaluating and optimizing the animal feeding diet. It was revealed that a computer system in the online mode would help to find the best option for a feeding ration, taking into account multifactor and limitations.

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Nanonet force microscopy for measuring forces in single smooth muscle cells of the human aorta

Molecular Biology of the Cell ◽

10.1091/mbc.e17-01-0053 ◽

2017 ◽

Vol 28 (14) ◽

pp. 1894-1900 ◽

Cited By ~ 9

Author(s):

Alexander Hall ◽

Patrick Chan ◽

Kevin Sheets ◽

Matthew Apperson ◽

Christopher Delaughter ◽

...

Keyword(s):

Smooth Muscle ◽

External Perturbation ◽

Human Aorta ◽

Cycle Times ◽

Force Microscopy ◽

Cell Matrix ◽

Innovative Methods ◽

A Cell ◽

Inside Out

A number of innovative methods exist to measure cell–matrix adhesive forces, but they have yet to accurately describe and quantify the intricate interplay of a cell and its fibrous extracellular matrix (ECM). In cardiovascular pathologies, such as aortic aneurysm, new knowledge on the involvement of cell–matrix forces could lead to elucidation of disease mechanisms. To better understand this dynamics, we measured primary human aortic single smooth muscle cell (SMC) forces using nanonet force microscopy in both inside-out (I-O intrinsic contractility) and outside-in (O-I external perturbation) modes. For SMC populations, we measured the I-O and O-I forces to be 12.9 ± 1.0 and 57.9 ± 2.5 nN, respectively. Exposure of cells to oxidative stress conditions caused a force decrease of 57 and 48% in I-O and O-I modes, respectively, and an increase in migration rate by 2.5-fold. Finally, in O-I mode, we cyclically perturbed cells at constant strain of varying duration to simulate in vivo conditions of the cardiac cycle and found that I-O forces decrease with increasing duration and O-I forces decreased by half at shorter cycle times. Thus our findings highlight the need to study forces exerted and felt by cells simultaneously to comprehensively understand force modulation in cardiovascular disease.

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Adhesive multiplicity in the interaction of embryonic fibroblasts and myoblasts with extracellular matrices.

The Journal of Cell Biology ◽

10.1083/jcb.99.4.1398 ◽

1984 ◽

Vol 99 (4) ◽

pp. 1398-1404 ◽

Cited By ~ 44

Author(s):

C Decker ◽

R Greggs ◽

K Duggan ◽

J Stubbs ◽

A Horwitz

Keyword(s):

Skeletal Muscle ◽

Cardiac Muscle ◽

Cardiac Fibroblasts ◽

Cell Types ◽

Extracellular Matrices ◽

Common Denominator ◽

Cell Matrix ◽

Skeletal Myoblasts ◽

A Cell ◽

Cell Matrix Adhesion

Neff et al. (1982, J. Cell Biol., 95:654-666) have described a monoclonal antibody, CSAT, directed against a cell surface antigen that participates in the adhesion of skeletal muscle to extracellular matrices. We used the same antibody to compare and parse the determinants of adhesion and morphology on myogenic and fibrogenic cells. We report here that the antigen is present on skeletal and cardiac muscle and on tendon, skeletal, dermal, and cardiac fibroblasts; however, its contribution to their morphology and adhesion is different. The antibody produces large alterations in the morphology and adhesion of skeletal myoblasts and tendon fibroblasts; in contrast, its effects on the cardiac fibroblasts are not readily detected. The effects of CSAT on the other cell types, i.e., dermal and skeletal fibroblasts, cardiac muscle, 5-bromodeoxyuridine-treated skeletal muscle, lie between these extremes. The effects of CSAT on the skeletal myoblasts depends on the calcium concentration in the growth medium and on the culture age. We interpret these differential responses to CSAT as revealing differences in the adhesion of the various cells to extracellular matrices. This interpretation is supported by parallel studies using quantitative assays of cell-matrix adhesion. The likely origin of these adhesive differences is the progressive display of different kinds of adhesion-related molecules and their organizational complexes on increasingly adhesive cells. The antigen to which CSAT is directed is present on all of the above cells and thus appears to be a lowest common denominator of their adhesion to extracellular matrices.

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Emulation with Organic Memristive Devices of Impairment of LTP Mechanism in Neurodegenerative Disease Pathology

Neural Plasticity ◽

10.1155/2017/6090312 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Silvia Battistoni ◽

Victor Erokhin ◽

Salvatore Iannotta

Keyword(s):

Neural Network ◽

Information Transmission ◽

Common Sense ◽

Artificial Neuron ◽

Cell Network ◽

Neuron Networks ◽

A Cell ◽

The Common ◽

Major Progress ◽

Single Synapse

We explore and demonstrate the extension of the synapse-mimicking properties of memristive devices to a dysfunctional synapse as it occurs in the Alzheimer’s disease (AD) pathology. The ability of memristive devices to reproduce synapse properties such as LTP, LTD, and STDP has been already widely demonstrated, and moreover, they were used for developing artificial neuron networks (perceptrons) able to simulate the information transmission in a cell network. However, a major progress would be to extend the common sense of neuromorphic device even to the case of dysfunction of natural synapses. Can memristors efficiently simulate them? We provide here evidences of the ability of emulating the dysfunctional synaptic behavior typical of the AD pathology with organic memristive devices considering the effect of the disease not only on a single synapse but also in the case of a neural network, composed by numerous synapses.

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Mycobacterium tuberculosisTransfer RNA Induces IL-12p70 via Synergistic Activation of Pattern Recognition Receptors within a Cell Network

The Journal of Immunology ◽

10.4049/jimmunol.1701733 ◽

2018 ◽

Vol 200 (9) ◽

pp. 3244-3258 ◽

Cited By ~ 5

Author(s):

Caroline Keegan ◽

Stephan Krutzik ◽

Mirjam Schenk ◽

Philip O. Scumpia ◽

Jing Lu ◽

...

Keyword(s):

Pattern Recognition ◽

Pattern Recognition Receptors ◽

Cell Network ◽

Synergistic Activation ◽

A Cell

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Strain-Dependent Impact of G and SH Deletions Provide New Insights for Live-Attenuated HMPV Vaccine Development

Vaccines ◽

10.3390/vaccines7040164 ◽

2019 ◽

Vol 7 (4) ◽

pp. 164 ◽

Cited By ~ 1

Author(s):

Julia Dubois ◽

Andrés Pizzorno ◽

Marie-Hélène Cavanagh ◽

Blandine Padey ◽

Claire Nicolas de Lamballerie ◽

...

Keyword(s):

Vaccine Development ◽

Specific Treatment ◽

Respiratory Pathogen ◽

Recombinant Viruses ◽

Human Airway Epithelium ◽

A Cell ◽

Strain Dependent ◽

Selection Of

Human metapneumovirus (HMPV) is a major pediatric respiratory pathogen with currently no specific treatment or licensed vaccine. Different strategies to prevent this infection have been evaluated, including live-attenuated vaccines (LAV) based on SH and/or G protein deletions. This approach showed promising outcomes but has not been evaluated further using different viral strains. In that regard, we previously showed that different HMPV strains harbor distinct in vitro fusogenic and in vivo pathogenic phenotypes, possibly influencing the selection of vaccine strains. In this study, we investigated the putative contribution of the low conserved SH or G accessory proteins in such strain-dependent phenotypes and generated recombinant wild type (WT) and SH- or G-deleted viruses derived from two different patient-derived HMPV strains, A1/C-85473 and B2/CAN98-75. The ΔSH and ΔG deletions led to different strain-specific phenotypes in both LLC-MK2 cell and reconstituted human airway epithelium models. More interestingly, the ΔG-85473 and especially ΔSH-C-85473 recombinant viruses conferred significant protection against HMPV challenge and induced immunogenicity against a heterologous strain. In conclusion, our results show that the viral genetic backbone should be considered in the design of live-attenuated HMPV vaccines, and that a SH-deleted virus based on the A1/C-85473 HMPV strain could be a promising LAV candidate as it is both attenuated and protective in mice while being efficiently produced in a cell-based system.

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The role of topology and mechanics in uniaxially growing cell networks

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2019.0523 ◽

2020 ◽

Vol 476 (2233) ◽

pp. 20190523

Author(s):

Alexander Erlich ◽

Gareth W. Jones ◽

Françoise Tisseur ◽

Derek E. Moulton ◽

Alain Goriely

Keyword(s):

Network Connectivity ◽

Tissue Level ◽

Tissue Response ◽

Cell Network ◽

Growing Cell ◽

A Cell ◽

Growth Laws ◽

Parallel Connections ◽

Cell Networks

In biological systems, the growth of cells, tissues and organs is influenced by mechanical cues. Locally, cell growth leads to a mechanically heterogeneous environment as cells pull and push their neighbours in a cell network. Despite this local heterogeneity, at the tissue level, the cell network is remarkably robust, as it is not easily perturbed by changes in the mechanical environment or the network connectivity. Through a network model, we relate global tissue structure (i.e. the cell network topology) and local growth mechanisms (growth laws) to the overall tissue response. Within this framework, we investigate the two main mechanical growth laws that have been proposed: stress-driven or strain-driven growth. We show that in order to create a robust and stable tissue environment, networks with predominantly series connections are naturally driven by stress-driven growth, whereas networks with predominantly parallel connections are associated with strain-driven growth.

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Ratiometric fluorescence imaging of endogenous selenocysteine in cancer cell matrix

Journal of Materials Chemistry B ◽

10.1039/c7tb01558e ◽

2017 ◽

Vol 5 (33) ◽

pp. 6890-6896 ◽

Cited By ~ 19

Author(s):

Yong Tian ◽

Fangyun Xin ◽

Congcong Gao ◽

Jing Jing ◽

Xiaoling Zhang

Keyword(s):

Fluorescence Imaging ◽

Cancer Cell ◽

Blue Emission ◽

Yellow Emission ◽

Fluorescence Ratio ◽

Ratiometric Fluorescence ◽

Specific Reaction ◽

Quantitative Correlation ◽

Cell Matrix ◽

A Cell

A ratiometric method for tracing the variation of selenocysteine (Sec) in a cell matrix was provided. This was constructed by the quantitative correlation between the fluorescence ratio ofRat-Sec(blue emission, the probe) andNap-OH(green-yellow emission, the product from a Sec-specific reaction) and the concentration of Sec.

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