Abstract:
:This paper presents a biomechanical model for the small pits, called crypts, that line the colon. A continuum approach is adopted, with the crypt epithelium modelled as a growing beam attached to the underlying lamina by cell bonds, which generate tension within the layer. These cell attachments are assumed to be viscoelastic thus allowing for cell progression along the crypt. It is shown that any combination of: an increase in net proliferation (i.e. cell production minus apoptosis), an enlargement of the proliferative compartment, an increase in the strength of the cellular attachment to the underlying lamina, or a change in the rate of cell growth or cell bonding may generate buckling of the tissue. These changes can all be generated by an activating mutation of the Wnt cascade, which is generally accepted to be the first genetic change in colorectal cancer, with subsequent deformation, budding, and crypt fission an observed feature of the adenomatous crypt.
journal_name
Bull Math Bioljournal_title
Bulletin of mathematical biologyauthors
Edwards CM,Chapman SJdoi
10.1007/s11538-007-9199-8subject
Has Abstractpub_date
2007-08-01 00:00:00pages
1927-42issue
6eissn
0092-8240issn
1522-9602journal_volume
69pub_type
杂志文章abstract::Synaptic spines grow as a consequence of the formation of F-actin filaments at the spine head. The dynamics of F-actin in the spine head upon excitation of N-methy-D-aspartate (NMDA) receptors has recently been investigated experimentally, but there is no quantitative account of how these dynamic changes occur upon ac...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-010-9614-4
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abstract::Two possible dangers of an extensive varicella vaccination program are more varicella (chickenpox) cases in adults, when the complication rates are higher, and an increase in cases of zoster (shingles). Here an age-structured epidemiologic-demographic model with vaccination is developed for varicella and zoster. Param...
journal_title:Bulletin of mathematical biology
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doi:10.1006/bulm.1999.0126
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abstract::This paper develops mathematical theory to determine the representativeness of clone libraries for various models, defined below in the text. In particular, the means and variances of fragment lengths and the mean of the length of a randomly selected fragment are determined, as well as the probability of the event tha...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1006/bulm.2001.0251
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journal_title:Bulletin of mathematical biology
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doi:10.1006/bulm.1997.0025
更新日期:1998-01-01 00:00:00
abstract::The comprehension of activities and functions of complex brain structures requires, among other things, information on simultaneous activities in several regions. Results reported in the literature using multi(micro/macro)electrode recordings or imaging techniques provide incomplete information due either to the small...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
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abstract::The insertion-deletion model developed by Thorne, Kishino and Felsenstein (1991, J. Mol. Evol., 33, 114-124; the TKF91 model) provides a statistical framework of two sequences. The statistical alignment of a set of sequences related by a star tree is a generalization of this model. The known algorithm computes the pro...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
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abstract::Integrins mediate cell adhesion and are essential receptors for the development and functioning of multicellular organisms. Integrin activation is known to require both ligand and talin binding and to correlate with cluster formation but the activation mechanism and precise roles of these processes are not yet resolve...
journal_title:Bulletin of mathematical biology
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journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
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abstract::Recent discoveries in ecological stoichiometry have indicated that food quality in terms of the phosphorus/carbon (P/C) ratio affects consumers whether the imbalance involves insufficient or excess nutrients. This phenomenon is called the "stoichiometric P/C knife-edge." In this study, we develop and analyze a produce...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
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journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
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abstract::A model employing separate dose-dependent response functions for proliferation and differentiation of idiotypically interacting B cell clones is presented. For each clone the population dynamics of proliferating B cells, non-proliferating B cells and free antibodies are considered. An effective response function, whic...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02460702
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abstract::We develop a numerical method for estimating optimal parameters in a mathematical model of the within-host dynamics of malaria infection. The model consists of a quasilinear system of partial differential equations. Convergence theory for the computed parameters is provided. Following this analysis, we present several...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-011-9650-8
更新日期:2011-11-01 00:00:00
abstract::Bovine Babesiosis (BB) is a tick borne parasitic disease with worldwide over 1.3 billion bovines at potential risk of being infected. The disease, also called tick fever, causes significant mortality from infection by the protozoa upon exposure to infected ticks. An important factor in the spread of the disease is the...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-013-9912-8
更新日期:2014-01-01 00:00:00
abstract::Radiation target theory has been extended to complex biochemical systems. Mathematical analyses are presented for multiple forms of biological active proteins, for the presence of large inhibitors or activators, for compounds which regulate rate or affinity and for multiple-step reactions. Several predictions of these...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02458298
更新日期:1995-11-01 00:00:00
abstract::A system of differential equations for the control of tumor cells growth in a cycle nonspecific chemotherapy is presented. Spontaneously acquired drug resistance is accounted for, as well as the evolution in time of normal cells. In addition, optimization of conflicting objectives forms the aim of the chemotherapeutic...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02458426
更新日期:1997-07-01 00:00:00
abstract::Identifiability concerns finding which unknown parameters of a model can be estimated, uniquely or otherwise, from given input-output data. If some subset of the parameters of a model cannot be determined given input-output data, then we say the model is unidentifiable. In this work, we study linear compartment models...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-015-0098-0
更新日期:2015-08-01 00:00:00
abstract::At least four distinct lineages of CD4+ T cells play diverse roles in the immune system. Both in vivo and in vitro, naïve CD4+ T cells often differentiate into a variety of cellular phenotypes. Previously, we developed a mathematical framework to study heterogeneous differentiation of two lineages governed by a mutual...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-015-0076-6
更新日期:2015-06-01 00:00:00
abstract::Two types of behavior have been previously reported in models of immune networks. The typical behavior of simple models, which involve B cells only, is stationary behavior involving several steady states. Finite amplitude perturbations may cause the model to switch between different equilibria. The typical behavior of...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02460673
更新日期:1993-01-01 00:00:00
abstract::Using optimal control theory as the basic theoretical tool, we investigate the efficacy of different antibiotic treatment protocols in the most exacting of circumstances, described as follows. Viewing a continuous culture device as a proxy for a much more complex host organism, we first inoculate the device with a sin...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-011-9698-5
更新日期:2012-04-01 00:00:00
abstract::We consider a minimalist model for the Sterile Insect Technique (SIT), assuming that residual fertility can occur in the sterile male population. Taking into account that we are able to get regular measurements from the biological system along the control duration, such as the size of the wild insect population, we st...
journal_title:Bulletin of mathematical biology
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abstract::With increasing fishing pressures having brought several stocks to the brink of collapse, there is a need for developing efficient harvesting methods that account for factors beyond merely yield or profit. We consider the dynamics and management of a stage-structured fish stock. Our work is based on a consumer-resourc...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-012-9789-y
更新日期:2013-01-01 00:00:00
abstract::Mathematical models are useful for providing a framework for integrating data and gaining insights into the static and dynamic behavior of complex biological systems such as networks of interacting genes. We review the dynamic behaviors expected from model gene networks incorporating common biochemical motifs, and we ...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章,评审
doi:10.1006/bulm.1999.0155
更新日期:2000-03-01 00:00:00
abstract::We study the emergence of collective spatio-temporal objects in biological systems by representing individually the elementary interactions between their microscopic components. We use the immune system as a prototype for such interactions. The results of this detailed explicit analysis are compared with the tradition...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1016/S0092-8240(03)00007-7
更新日期:2003-05-01 00:00:00
abstract::Autoinhibition of neurotransmitter release occurs via binding of transmitter to appropriate receptors. Experiments have provided evidence suggesting that the control of neurotransmitter release in fast systems is mediated by these inhibitory autoreceptors. Earlier, the authors formulated and analysed a mathematical mo...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1006/bulm.2000.0174
更新日期:2000-07-01 00:00:00
abstract::We present a new symmetric model of the idiotypic immune network. The model specifies clones of B-lymphocytes and incorporates: (1) influx and decay of cells; (2) symmetric stimulatory and inhibitory idiotypic interactions; (3) an explicit affinity parameter (matrix); (4) external (i.e. non-idiotypic) antigens. Suppre...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02458444
更新日期:1989-01-01 00:00:00
abstract::A rather complete model of the gluconeogenic pathway was used, with the known separate pools of mitochondrial and cytosolic oxalacetate, malate and aspartate. The fumarase, malate dehydrogenase and glutamate oxalacetate transaminase reactions were assumed to be isotopically actively reversible, but none at isotopic eq...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/BF02460783
更新日期:1995-07-01 00:00:00
abstract::Chemical reactions are discrete, stochastic events. As such, the species' molecular numbers can be described by an associated master equation. However, handling such an equation may become difficult due to the large size of reaction networks. A commonly used approach to forecast the behaviour of reaction networks is t...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-014-9985-z
更新日期:2014-09-01 00:00:00
abstract::Dispersal heterogeneity is increasingly being observed in ecological populations and has long been suspected as an explanation for observations of non-Gaussian dispersal. Recent empirical and theoretical studies have begun to confirm this. Using an integro-difference model, we allow an individual's diffusivity to be d...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-014-0014-z
更新日期:2014-11-01 00:00:00
abstract::In this paper, we present computational techniques to investigate the effect of surface geometry on biological pattern formation. In particular, we study two-component, nonlinear reaction-diffusion (RD) systems on arbitrary surfaces. We build on standard techniques for linear and nonlinear analysis of RD systems and e...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1007/s11538-017-0255-8
更新日期:2017-04-01 00:00:00
abstract::Cycles in biological populations have been shown to arise from enemy-victim systems, delayed density dependence, and maternal effects. In an initial effort to model the year-to-year dynamics of natural populations of entomopathogenic nematodes and their insect hosts, we find that a simple, nonlinear, mechanistic model...
journal_title:Bulletin of mathematical biology
pub_type: 杂志文章
doi:10.1016/j.bulm.2003.09.005
更新日期:2004-05-01 00:00:00