MODELLING THREE-DIMENSIONAL GROWTH OF BRAIN TUMOURS FROM TIME SERIES OF SCANS

The development of brain tumours, after diagnosis, is routinely recorded by different medical imaging techniques like computerised tomography (CT) or magnetic resonance imaging (MRI). However, it is only through the formulation of mathematical models that an analysis of the spatio-temporal tumour growth revealed on each patient serial scans can lead to a quantification of parameters characterising the proliferative and expensive dynamic of the brain tumour. This paper reviews some of the results and limitations encountered in modelling the different stages of a brain tumour growth, namely before and after diagnosis and therapy. It extends an original two-dimensional approach by considering three-dimensional growth of brain tumours submitted to the spatial constraints exerted by the skull and ventricles boundaries. Considering the dynamic of both the pre- and post-diagnosis stages, the tumour growth patterns obtained with various combinations of nonlinear growth rates and cellular diffusion laws are considered and compared to real MRI scans taken in a patient with a glioblastoma and having undergone radiotherapy. From these simulations, we characterise the effects of different therapies on survival durations, with special attention to the effect of cell diffusion inside the resected brain region when surgical resection of the tumour is carried out.

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Significance of three-dimensional growth patterns of mammary tissues in collagen gels

In Vitro ◽

10.1007/bf02619573 ◽

1983 ◽

Vol 19 (8) ◽

pp. 600-610 ◽

Cited By ~ 36

Author(s):

Ellen M. Lawler ◽

Fred R. Miller ◽

Gloria H. Heppner

Keyword(s):

Three Dimensional ◽

Growth Patterns ◽

Collagen Gels ◽

Dimensional Growth ◽

Mammary Tissues

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Enhancing the spatio-temporal features of polar mesosphere summer echoes using coherent MIMO and radar imaging at MAARSY

10.5194/amt-2018-258 ◽

2018 ◽

Cited By ~ 1

Author(s):

Juan Miguel Urco ◽

Jorge Luis Chau ◽

Tobias Weber ◽

Ralph Latteck

Keyword(s):

Angular Resolution ◽

Imaging Techniques ◽

Three Dimensional ◽

Radar Imaging ◽

Horizontal Resolution ◽

Atmospheric Dynamics ◽

Polar Regions ◽

Background Wind ◽

Summer Echoes ◽

Spatio Temporal

Abstract. Polar mesospheric summer echoes (PMSEs) are very strong radar echoes caused by the presence of ice particles, turbulence, and free electrons in the mesosphere over polar regions. For more than three decades, PMSEs have been used as natural tracers of the complicated atmospheric dynamics of this region. Neutral winds and turbulence parameters have been obtained assuming PMSE horizontal homogeneity in scales of tens of kilometers. Recent radar imaging studies have shown that PMSEs are not homogeneous in these scales and instead they are composed of kilometer-scale structures. In this paper, we present a technique that allows PMSE observations with unprecedented angular resolution (~ 0.6°). The technique combines the concept of coherent MIMO (Multi-input multiple-output) and two high-resolution imaging techniques, i.e., Capon and Maximum Entropy (MaxEnt). The resulting resolution is evaluated by imaging specular meteor echoes. The gain in angular resolution compared to previous approaches using SIMO (single input and multiple-output) and Capon is at least a factor of 2, i.e., at 85 km, we obtain a horizontal resolution of ~ 900 meters. The goodness of the new technique is evaluated with two events of three-dimensional PMSEs structures showing: (1) horizontal wavelengths of 8–10 km and periods of 4–7 minutes, drifting with the background wind, and (2) horizontal wavelengths of 12–16 km and periods of 15–20 minutes not drifting with the background wind. Besides the advantages of the implemented technique, we discuss its current challenges, like the use of reduced power-aperture and processing time, as well as the future opportunities for improving the understanding of the complex atmospheric dynamics behind PMSEs.

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A digital 3D reference atlas reveals cellular growth patterns shaping the Arabidopsis ovule

eLife ◽

10.7554/elife.63262 ◽

2021 ◽

Vol 10 ◽

Author(s):

Athul Vijayan ◽

Rachele Tofanelli ◽

Sören Strauss ◽

Lorenzo Cerrone ◽

Adrian Wolny ◽

...

Keyword(s):

Gene Expression ◽

Expression Patterns ◽

Three Dimensional ◽

Temporal Analysis ◽

Growth Patterns ◽

Cellular Growth ◽

Nucellar Cell ◽

Control Of Gene Expression ◽

Molecular Control ◽

Spatio Temporal

A fundamental question in biology is how morphogenesis integrates the multitude of processes that act at different scales, ranging from the molecular control of gene expression to cellular coordination in a tissue. Using machine-learning-based digital image analysis, we generated a three-dimensional atlas of ovule development in Arabidopsis thaliana, enabling the quantitative spatio-temporal analysis of cellular and gene expression patterns with cell and tissue resolution. We discovered novel morphological manifestations of ovule polarity, a new mode of cell layer formation, and previously unrecognized subepidermal cell populations that initiate ovule curvature. The data suggest an irregular cellular build-up of WUSCHEL expression in the primordium and new functions for INNER NO OUTER in restricting nucellar cell proliferation and the organization of the interior chalaza. Our work demonstrates the analytical power of a three-dimensional digital representation when studying the morphogenesis of an organ of complex architecture that eventually consists of 1900 cells.

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Broad application of non-invasive imaging techniques to echinoids and other echinoderm taxa*

Zoosymposia ◽

10.11646/zoosymposia.7.1.6 ◽

2012 ◽

Vol 7 (1) ◽

pp. 53-70 ◽

Cited By ~ 19

Author(s):

ALEXANDER ZIEGLER

Keyword(s):

Sea Urchin ◽

Large Scale ◽

Sea Urchins ◽

Imaging Techniques ◽

Three Dimensional ◽

Image Data ◽

Micro Computed Tomography ◽

Non Invasive ◽

Mri Scans ◽

Three Dimensional Models

Tomographic imaging techniques such as micro-computed tomography (μCT) and magnetic resonance imaging (MRI) permit the gathering of digital anatomical data from whole animal specimens non-invasively. The resulting datasets can be used for direct observation of the two-dimensional tomographic image data as well as for manual and semi-automated three-dimensional modelling. Freshly fixed specimens as well as preserved museum material can be successfully analyzed using this approach, giving the zoomorphologist a powerful tool for large-scale comparative studies. In order to demonstrate the principle suitability of non-invasive imaging in echinoderm research, μCT scans of 199 and MRI scans of 92 sea urchin (Echinodermata: Echinoidea) species were acquired, resulting in a total of 203 analyzed echinoid species. The taxa selected represent 50 of the currently recognized 60 extant sea urchin families. The present article lists all species that have been analyzed so far and provides information about the scanning parameters employed for each dataset. Furthermore, the workflow established to generate three-dimensional models of sea urchins is outlined. Using a number of examples from μCT as well as MRI scans performed on echinoids, the potential of the systematic approach described here is highlighted. Finally, the suitability of non-invasive imaging techniques for the study of other echinoderm taxa is assessed based on multimodal datasets of representative species.

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Three-dimensional growth patterns of various human tumor cell lines in simulated microgravity of a NASA bioreactor

In Vitro Cellular & Developmental Biology - Animal ◽

10.1007/s11626-997-0064-8 ◽

1997 ◽

Vol 33 (6) ◽

pp. 459-466 ◽

Cited By ~ 149

Author(s):

M. Ingram ◽

G. B. Techy ◽

R. Saroufeem ◽

O. Yazan ◽

K. S. Narayan ◽

...

Keyword(s):

Tumor Cell ◽

Cell Lines ◽

Simulated Microgravity ◽

Three Dimensional ◽

Human Tumor ◽

Growth Patterns ◽

Tumor Cell Lines ◽

Human Tumor Cell ◽

Human Tumor Cell Lines ◽

Dimensional Growth

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Mitochondrial Reconstructions Based on Serial Thick Sections and HVEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115055 ◽

1975 ◽

Vol 33 ◽

pp. 286-287

Author(s):

Jerome J. Paulin

Keyword(s):

Imaging Techniques ◽

Three Dimensional ◽

Posterior Pole ◽

Dimensional Structure ◽

Stereo Imaging ◽

Thin Sections ◽

Anatomical Features ◽

The Past ◽

Cellular Components ◽

Mitochondrial Reticulum

Within the past decade it has become apparent that HVEM offers the biologist a means to explore the three-dimensional structure of cells and/or organelles. Stereo-imaging of thick sections (e.g. 0.25-10 μm) not only reveals anatomical features of cellular components, but also reduces errors of interpretation associated with overlap of structures seen in thick sections. Concomitant with stereo-imaging techniques conventional serial Sectioning methods developed with thin sections have been adopted to serial thick sections (≥ 0.25 μm). Three-dimensional reconstructions of the chondriome of several species of trypanosomatid flagellates have been made from tracings of mitochondrial profiles on cellulose acetate sheets. The sheets are flooded with acetone, gluing them together, and the model sawed from the composite and redrawn.The extensive mitochondrial reticulum can be seen in consecutive thick sections of (0.25 μm thick) Crithidia fasciculata (Figs. 1-2). Profiles of the mitochondrion are distinguishable from the anterior apex of the cell (small arrow, Fig. 1) to the posterior pole (small arrow, Fig. 2).

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Image formation analysis of thick biological specimens using three-dimensional power-spectra of through focus series

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168359 ◽

1994 ◽

Vol 52 ◽

pp. 124-125

Author(s):

Karen F. Han

Keyword(s):

Inelastic Scattering ◽

Imaging Techniques ◽

Mass Density ◽

Relative Proportion ◽

Three Dimensional ◽

Power Spectra ◽

Image Formation ◽

Energy Filtering ◽

Ewald Sphere ◽

Nonlinear Imaging

The primary focus in our laboratory is the study of higher order chromatin structure using three dimensional electron microscope tomography. Three dimensional tomography involves the deconstruction of an object by combining multiple projection views of the object at different tilt angles, image intensities are not always accurate representations of the projected object mass density, due to the effects of electron-specimen interactions and microscope lens aberrations. Therefore, an understanding of the mechanism of image formation is important for interpreting the images. The image formation for thick biological specimens has been analyzed by using both energy filtering and Ewald sphere constructions. Surprisingly, there is a significant amount of coherent transfer for our thick specimens. The relative amount of coherent transfer is correlated with the relative proportion of elastically scattered electrons using electron energy loss spectoscopy and imaging techniques.Electron-specimen interactions include single and multiple, elastic and inelastic scattering. Multiple and inelastic scattering events give rise to nonlinear imaging effects which complicates the interpretation of collected images.

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