Interaction of epithelium with mesenchyme affects global features of lung architecture: a computer model of development

Lung airway morphogenesis is simulated in a simplified diffusing environment that simulates the mesenchyme to explore the role of morphogens in airway architecture development. Simple rules govern local branching morphogenesis. Morphogen gradients are modeled by four pairs of sources and their diffusion through the mesenchyme. Sensitivity to lobar architecture and mesenchymal morphogen are explored. Even if the model accurately represents observed patterns of local development, it could not produce realistic global patterns of lung architecture if interaction with its environment was not taken into account, implying that reciprocal interaction between airway growth and morphogens in the mesenchyme plays a critical role in producing realistic global features of lung architecture.

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PDGF-AA and its receptor influence early lung branching via an epithelial-mesenchymal interaction

Development ◽

10.1242/dev.121.8.2559 ◽

1995 ◽

Vol 121 (8) ◽

pp. 2559-2567 ◽

Cited By ~ 3

Author(s):

P. Souza ◽

M. Kuliszewski ◽

J. Wang ◽

I. Tseu ◽

A.K. Tanswell ◽

...

Keyword(s):

Dna Synthesis ◽

Critical Role ◽

Polymerase Chain Reaction Analysis ◽

Branching Morphogenesis ◽

Inhibitory Effect ◽

Embryonic Lung ◽

Morphometric Analyses ◽

Terminal Buds ◽

Lung Branching

The biological role of platelet-derived growth factor (PDGF)-AA in lung morphogenesis was investigated by incubating embryonic lung explants with phosphorothioate antisense PDGF-A oligonucleotides, which decreased PDGF-AA but not PDGF-BB protein content. Antisense PDGF-A oligonucleotides inhibited DNA synthesis. This inhibitory effect of antisense PDGF-A was reversed by the addition of exogenous PDGF-AA but not PDGF-BB. Morphometric analyses of antisense-treated cultures showed a significant reduction in lung size. The number of terminal buds of the lung explants was significantly decreased by antisense PDGF-A oligonucleotides. PDGF-AA but not PDGF-BB attenuated the inhibitory effect of antisense PDGF-A on early lung branching. Sense PDGF-A had no effect on DNA synthesis and early lung branching. Reverse transcriptase-polymerase chain reaction analysis revealed PDGF-A mRNA expression in the epithelial component of the embryonic lung, while message for PDGF alpha-receptor was expressed in the mesenchyme. Incubation of explants with neutralizing PDGF-AA antibodies also reduced DNA synthesis and early branching morphogenesis. We conclude that PDGF-AA and its receptor represent an important epithelial-mesenchymal interaction which plays a critical role in early lung branching morphogenesis.

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Identification of Cellular Recognition Sequence of Epimorphin and Critical Role of Cell/Epimorphin Interaction in Lung Branching Morphogenesis

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.1997.6673 ◽

1997 ◽

Vol 234 (2) ◽

pp. 522-525 ◽

Cited By ~ 19

Author(s):

Shogo Koshida ◽

Yohei Hirai

Keyword(s):

Critical Role ◽

Branching Morphogenesis ◽

Recognition Sequence ◽

Cellular Recognition ◽

Lung Branching

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WINNING A BATTLE: THE IMPORTANCE OF KNOWING THE “NEIGHBORHOOD”

International Journal of Modern Physics E ◽

10.1142/s021830130801026x ◽

2008 ◽

Vol 17 (05) ◽

pp. 924-929 ◽

Cited By ~ 1

Author(s):

LINDA SHANAHAN ◽

SURAJIT SEN

Keyword(s):

Lattice Model ◽

Depth Analysis ◽

Simple Rules ◽

Global Patterns

We propose that a battle between two conflicting entities can be modeled as a kinematic problem on a lattice. We examine the parameters relevant to such simulations, and describe global patterns emerging from a lattice model of a conflict with a few simple rules. We conclude that models of this type display interesting and relevant properties and warrant more in-depth analysis. The focus in this work is on the role of knowledge of the “neighborhood” in winning a battle.

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Iterated Growth

Natural Complexity ◽

10.23943/princeton/9780691176840.003.0002 ◽

2017 ◽

Author(s):

Paul Charbonneau

Keyword(s):

Cellular Automata ◽

Growth Process ◽

A Priori ◽

Natural World ◽

General Idea ◽

Complex Shapes ◽

Simple Rules ◽

Spatial Dimensions ◽

Global Patterns

This chapter shows how complex shapes and forms encountered in the natural world result from a growth process driven by the repeated action of simple “rules.” To examine this general idea, the chapter focuses on cellular automata, arguably the simplest type of computer programs conceivable yet can sometimes exhibit behaviors that are extremely complex. Cellular automata are also a classic example of simple rules being able to produce complex global “patterns” that cannot be inferred or predicted even if we have complete, a priori knowledge of these rules. The chapter first considers cellular automata in one and two spatial dimensions before discussing a zoo of two-dimensional structures from simple rules. It then describes the role of agents in iterated growth as well as emergent structures and behaviors that can be produced by cellular automata. The chapter includes exercises and further computational explorations, along with suggested materials for further reading.

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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