The statistics of noisy growth with mechanical feedback in elastic tissues

Mapping Intimacies ◽

10.1101/426361 ◽

2018 ◽

Author(s):

Ojan Khatib Damavandi ◽

David K. Lubensky

Keyword(s):

Tissue Growth ◽

Fundamental Aspect ◽

Isotropic Case ◽

Anisotropic Growth ◽

Clone Size ◽

Density Correlation ◽

Precise Control ◽

Growth Modes ◽

Elastic Sheets ◽

Mechanical Feedback

Tissue growth is a fundamental aspect of development and is intrinsically noisy. Stochasticity has important implications for morphogenesis, precise control of organ size, and regulation of tissue composition and heterogeneity. Yet, the basic statistical properties of growing tissues, particularly when growth induces mechanical stresses that can in turn affect growth rates, have received little attention. Here, we study the noisy growth of elastic sheets subject to mechanical feedback. Considering both isotropic and anisotropic growth, we find that the density-density correlation function shows power law scaling. We also consider the dynamics of marked, neutral clones of cells. We find that the areas (but not the shapes) of two clones are always statistically independent, even when they are adjacent. For anisotropic growth, we show that clone size variance scales like the average area squared and that the mode amplitudes characterizing clone shape show a slow 1/n decay, where n is the mode index. This is in stark contrast to the isotropic case, where relative variations in clone size and shape vanish at long times. The high variability in clone statistics observed in anisotropic growth is due to the presence of two soft modes—growth modes that generate no stress. Our results lay the groundwork for more in-depth explorations of the properties of noisy tissue growth in specific biological contexts.

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Statistics of noisy growth with mechanical feedback in elastic tissues

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1816100116 ◽

2019 ◽

Vol 116 (12) ◽

pp. 5350-5355 ◽

Cited By ~ 2

Author(s):

Ojan Khatib Damavandi ◽

David K. Lubensky

Keyword(s):

Tissue Growth ◽

Fundamental Aspect ◽

Isotropic Case ◽

Anisotropic Growth ◽

Clone Size ◽

Density Correlation ◽

Precise Control ◽

Growth Modes ◽

Elastic Sheets ◽

Mechanical Feedback

Tissue growth is a fundamental aspect of development and is intrinsically noisy. Stochasticity has important implications for morphogenesis, precise control of organ size, and regulation of tissue composition and heterogeneity. However, the basic statistical properties of growing tissues, particularly when growth induces mechanical stresses that can in turn affect growth rates, have received little attention. Here, we study the noisy growth of elastic sheets subject to mechanical feedback. Considering both isotropic and anisotropic growth, we find that the density–density correlation function shows power law scaling. We also consider the dynamics of marked, neutral clones of cells. We find that the areas (but not the shapes) of two clones are always statistically independent, even when they are adjacent. For anisotropic growth, we show that clone size variance scales like the average area squared and that the mode amplitudes characterizing clone shape show a slow1/ndecay, where n is the mode index. This is in stark contrast to the isotropic case, where relative variations in clone size and shape vanish at long times. The high variability in clone statistics observed in anisotropic growth is due to the presence of two soft modes—growth modes that generate no stress. Our results lay the groundwork for more in-depth explorations of the properties of noisy tissue growth in specific biological contexts.

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Boundedness of Solutions of Parabolic Equations With Anisotropic Growth Conditions

Canadian Journal of Mathematics ◽

10.4153/cjm-1997-040-2 ◽

1997 ◽

Vol 49 (4) ◽

pp. 798-809 ◽

Cited By ~ 4

Author(s):

Yu Mingqi ◽

Lian Xiting

Keyword(s):

Parabolic Equation ◽

Parabolic Equations ◽

Growth Conditions ◽

Isotropic Case ◽

Anisotropic Growth ◽

Boundedness Of Solutions

AbstractIn this paper, we consider the parabolic equation with anisotropic growth conditions, and obtain some criteria on boundedness of solutions, which generalize the corresponding results for the isotropic case.

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Patterning of Cell Attachment to Biocompatible Glassy Polymeric Carbon by Silver Ion Implantation

MRS Proceedings ◽

10.1557/proc-0942-w11-28 ◽

2006 ◽

Vol 942 ◽

Author(s):

Robert Lee Zimmerman ◽

Ismet Gurhan ◽

Daryush Ila ◽

F. Ozdal-Kurt ◽

B. H. Sen ◽

...

Keyword(s):

Ion Implantation ◽

Cell Attachment ◽

Blood Stream ◽

Tissue Growth ◽

Silver Ion ◽

Near Surface ◽

Precise Control ◽

In Vitro Biocompatibility ◽

Polymeric Carbon

ABSTRACTAlthough Glassy Polymeric Carbon (GPC) is ideally suited for implants in the blood stream, tissue that normally forms around the moving parts of a GPC heart valve. There is concern that the tissue lose adhesion and create the condition for embolisms downstream. We have shown that silver ion implantation or argon ion assisted surface deposition of silver inhibits cell growth on GPC, a desirable improvement of current cardiac implants. In vitro biocompatibility tests have been carried out with model cell lines to demonstrate that near surface implantation of silver in GPC can completely inhibit cell attachment on implanted areas while leaving adjacent areas unaffected. Patterned ion implantation permits precise control of tissue growth on medical applications of GPC.

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Faculty Opinions recommendation of Mechanical feedback as a possible regulator of tissue growth.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1024508.793577093 ◽

2020 ◽

Author(s):

Olivier Hamant

Keyword(s):

Tissue Growth ◽

Mechanical Feedback

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Mechanical feedback as a possible regulator of tissue growth

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0404782102 ◽

2005 ◽

Vol 102 (9) ◽

pp. 3318-3323 ◽

Cited By ~ 364

Author(s):

B. I. Shraiman

Keyword(s):

Tissue Growth ◽

Mechanical Feedback

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A Novel Reconstitution Method for Inducing the Formation of Regular 2-Dimensional Arrays of Membrane Proteins and Lipids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102845 ◽

1988 ◽

Vol 46 ◽

pp. 152-153 ◽

Cited By ~ 1

Author(s):

A. Engel ◽

A. Holzenburg ◽

K. Stauffer ◽

J. Rosenbusch ◽

U. Aebi

Keyword(s):

Membrane Proteins ◽

Flow Rate ◽

Lipid Membranes ◽

Functional Characterization ◽

Dimensional Structure ◽

Electron Crystallography ◽

Peltier Element ◽

Protein Ratio ◽

Precise Control ◽

3 Dimensional

Reconstitution of solubilized and purified membrane proteins in the presence of phospholipids into vesicles allows their functions to be studied by simple bulk measurements (e.g. diffusion of differently sized solutes) or by conductance measurements after transformation into planar membranes. On the other hand, reconstitution into regular protein-lipid arrays, usually forming at a specific lipid-to-protein ratio, provides the basis for determining the 3-dimensional structure of membrane proteins employing the tools of electron crystallography.To refine reconstitution conditions for reproducibly inducing formation of large and highly ordered protein-lipid membranes that are suitable for both electron crystallography and patch clamping experiments aimed at their functional characterization, we built a flow-dialysis device that allows precise control of temperature and flow-rate (Fig. 1). The flow rate is generated by a peristaltic pump and can be adjusted from 1 to 500 ml/h. The dialysis buffer is brought to a preselected temperature during its travel through a meandering path before it enters the dialysis reservoir. A Z-80 based computer controls a Peltier element allowing the temperature profile to be programmed as function of time.

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Multiple-fracturing and viewing of the same frozen sample at different depths using a low temperature FESEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166567 ◽

1996 ◽

Vol 54 ◽

pp. 820-821

Author(s):

M.V. Parthasarathy ◽

C. Daugherty

Keyword(s):

Temperature Field ◽

Low Temperature ◽

Field Emission ◽

Multiple Fracture ◽

Precise Control ◽

Cold Stage ◽

Different Depths ◽

Transfer Device

The versatility of Low Temperature Field Emission SEM (LTFESEM) for viewing frozen-hydrated biological specimens, and the high resolutions that can be obtained with such instruments have been well documented. Studies done with LTFESEM have been usually limited to the viewing of small organisms, organs, cells, and organelles, or viewing such specimens after fracturing them.We use a Hitachi 4500 FESEM equipped with a recently developed BAL-TEC SCE 020 cryopreparation/transfer device for our LTFESEM studies. The SCE 020 is similar in design to the older SCU 020 except that instead of having a dedicated stage, the SCE 020 has a detachable cold stage that mounts on to the FESEM stage when needed. Since the SCE 020 has a precisely controlled lock manipulator for transferring the specimen table from the cryopreparation chamber to the cold stage in the FESEM, and also has a motor driven microtome for precise control of specimen fracture, we have explored the feasibility of using the LTFESEM for multiple-fracture studies of the same sample.

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Rheometers, Bioreactors, and Vocalization Forces: Using Basic Science Investigations to Help the Voices of Teachers

Perspectives on Voice and Voice Disorders ◽

10.1044/vvd18.3.119 ◽

2008 ◽

Vol 18 (3) ◽

pp. 119-125

Author(s):

Sarah Klemuk

Keyword(s):

Basic Science ◽

Tissue Growth ◽

University Of Iowa ◽

Support Cell ◽

Rest Periods ◽

Collaborative Studies ◽

Professional Voice Users ◽

The University ◽

Science Investigations ◽

Professional Voice

Abstract Collaborative studies at the University of Iowa and the National Center for Voice and Speech aim to help the voices of teachers. Investigators study how cells and tissues respond to vibration doses simulating typical vocalization patterns of teachers. A commercially manufactured instrument is uniquely modified to support cell and tissue growth, to subject tissues to vocalization-like forces, and to measure viscoelastic properties of tissues. Through this basic science approach, steps toward safety limits for vocalization and habilitating rest periods for professional voice users will be achieved.

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