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Chauviere A - - 2010
Cell migration involves different mechanisms in different cell types and tissue environments. Changes in migratory behaviour have been observed experimentally and associated with phenotypic switching in various situations, such as the migration-proliferation dichotomy of glioma cells, the epithelial-mesenchymal transition or the mesenchymal-amoeboid transition of fibrosarcoma cells in the extracellular matrix ...
Bogle Gib - - 2010
Recent intravital microscopy experiments have revealed the complex behavior of T cells within lymph nodes. Modeling T-cell responses in lymph nodes now requires integration of cell trafficking and motility with the molecular processes involved in T-cell activation. We describe an agent-based model that allows such integration, in which T cells ...
Bock Andreas - - 2009
An assay for measuring the number of adherent cells on microcarriers that is independent from dilution errors in sample preparation was used to investigate attachment dynamics and cell growth. It could be shown that the recovery of seeded cells is a function of the specific rates of cell attachment and ...
Roach Kenneth L - - 2009
Advances in systems biology and bioinformatics have highlighted that no cell population is truly uniform and that stochastic behavior is an inherent property of many biological systems. As a result, bulk measurements can be misleading even when particular care has been taken to isolate a single cell type, and measurements ...
Diplas Andreas I - - 2009
Loss of imprinting (LOI) is the reactivation of the silenced allele of an imprinted gene, leading to perturbation of monoallelic expression. We tested the hypothesis that LOI of PLAGL1, a representative maternally imprinted gene, occurs through an all-or-none process leading to a mixture of fully imprinted and nonimprinted cells. Herein ...
Dailey H L - - 2010
The reopening of fluid-occluded pulmonary airways generates microbubble flows which impart complex hydrodynamic stresses to the epithelial cells lining airway walls. In this study we used boundary element solutions and finite element techniques to investigate how cell rheology influences the deformation and injury of cells during microbubble flows. An optimized ...
Mazzuferi Manuela - - 2010
Printed circuit board (PCB) technology can be used for producing lab-on-a-chip (LOAC) devices. PCBs are characterized by low production costs and large-scale development, both essential elements in the frame of disposable applications. LOAC platforms have been employed not only for diagnostic and/or analytical purposes, but also for identification and isolation ...
Baker Ruth E - - 2010
Cell migration and growth are essential components of the development of multicellular organisms. The role of various cues in directing cell migration is widespread, in particular, the role of signals in the environment in the control of cell motility and directional guidance. In many cases, especially in developmental biology, growth ...
Maenhaut C - - 2010
The concept of cancer stem cells (CSC) embodies two aspects: the stem cell as the initial target of the oncogenic process and the existence of two populations of cells in cancers: the CSC and derived cells. The second is discussed in this review. CSC are defined as cells having three ...
Walker D C - - 2010
The characteristics of biological tissues are determined by the interactions of large numbers of autonomous cells. These interactions can be mediated remotely by diffusive biochemical factors, or by direct cell-cell contact. E-cadherin is a protein expressed on the surface of normal epithelial cells that plays a key role in mediating ...
Ouaknin Gaddiel Yonathan - - 2009
The classical approach to model collective biological cell movement is through coupled nonlinear reaction-diffusion equations for biological cells and diffusive chemicals that interact with the biological cells. This approach takes into account the diffusion of cells, proliferation, death of cells, and chemotaxis. Whereas the classical approach has many advantages, it ...
O'Dea R D - - 2010
The growth of a cell population within a rigid porous scaffold in a perfusion bioreactor is studied, using a three-phase continuum model of the type presented by Lemon et al. (2006, Multiphase modelling of tissue growth using the theory of mixtures. J. Math. Biol., 52, 571-594) to represent the cell ...
Barnes Piers R F - - 2009
Photocurrents generated by thick, strongly absorbing, dye-sensitized cells were reduced when the electrolyte iodine concentration was increased. Electron diffusion lengths measured using common transient techniques (L(n)) were at least two times higher than diffusion lengths measured at steady state (L(IPCE)). Charge collection efficiency calculated using L(n) seriously overpredicted photocurrent, while ...
Zhang Y L - - 2009
A prototype for automatic control of mechanical forces acting on cell biomembranes is proposed in this paper. This prototype consists of vision-guided position control of the holder and micro-force sensor, automatic mechanical property characterization of cell biomembranes and automatic control of mechanical forces acting on cell biomembranes. A template-free calibration ...
Picard C - - 2009
The mechanical behaviour of adherent cells cultured in vitro is known to be dependent on the mechanical properties of the substrate. We show that this mechanical behaviour is also strongly affected by the cells' environment. We focus here on the impact of temperature and pH. Experiments carried out on individual ...
Ateshian Gerard A - - 2009
A framework is formulated within the theory of mixtures for continuum modeling of biological tissue growth that explicitly addresses cell division, using a homogenized representation of cells and their extracellular matrix (ECM). The model relies on the description of the cell as containing a solution of water and osmolytes, and ...
Moreno-Flores Susana - - 2010
Biomechanics is gaining relevance as complementary discipline to structural and cellular biology. The response of cells to mechanical stimuli determines cell type and function, while the spatial distribution of mechanical forces within the cells is crucial to understand cell activity. The experimental methodologies to approach cell mechanics are diverse but ...
Maggi Mat?as - - 2010
We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled ...
Stolarska Magdalena A - - 2009
Cell and tissue movement are essential processes at various stages in the life cycle of most organisms. The early development of multi-cellular organisms involves individual and collective cell movement; leukocytes must migrate towards sites of infection as part of the immune response; and in cancer, directed movement is involved in ...
McGarry J P - - 2009
A bio-chemo-mechanical model has been used to predict the contractile responses of smooth cells on a bed of micro-posts. Predictions obtained for smooth muscle cells reveal that, by converging onto a single set of parameters, the model captures all of the following responses in a self-consistent manner: (i) the scaling ...
Chung C A - - 2009
The Boyden chamber assay provides a convenient method of assessing cell migration and measuring cell motility coefficients at the population level. Previous models of this assay completely ignore cell sedimentation in the suspension, assuming that all cells have already settled on the filter surface before commencing migration within the filter. ...
Pleass Richard J - - 2009
Two recent papers published in Immunity and Cell Host & Microbe underline the great importance of B cells and of antibodies (Abs) in orchestrating crucial T helper cell type 2 (Th2) protective immune responses to gastrointestinal nematodes. The findings in animal models now raise major questions as to how B ...
Sch??le Birgitt - - 2009
The study of mechanisms that underlie Parkinson's disease (PD), as well as translational drug development, has been hindered by the lack of appropriate models. Both cell culture systems and animal models have limitations, and to date none faithfully recapitulate all of the clinical and pathological phenotypes of the disease. In ...
Starostová Zuzana - - 2009
The metabolic theory of ecology (MTE) predicts the ubiquity of the of 3/4 scaling exponent relating metabolic rate (MR) to body mass, as well as cell-size invariance coupled with body-size dependence of cellular MR in quickly dividing cells. An alternative prediction is that MR scales interspecifically with a coefficient that ...
Fitzpatrick Kathleen M - - 2009
Parkinson's disease (PD) researchers have pioneered the use of cell-based therapies (CBTs) in the central nervous system. CBTs for PD were originally envisioned as a way to replace the dopaminergic nigral neurons lost with the disease. Several sources of catecholaminergic cells, including autografts of adrenal medulla and allografts or xenografts ...
Paciello Lucia - - 2010
A cultural system, aimed at the production of glucoamylase with cells of a non-conventional yeast transformed for the enzyme expression, Kluyveromyces lactis JA6-GAA was realised. Glucoamylase production was accomplished in a reactor operating in fed batch mode to avoid limitations with respect to oxygen transfer, and achieve high cell density. ...
Geitmann Anja - - 2009
Cellular expansive growth is one of the foundations of morphogenesis. In plant and fungal cells, expansive growth is ultimately determined by manipulating the mechanics of the cell wall. Therefore, theoretical and biophysical descriptions of cellular growth processes focus on mathematical models of cell wall biomechanical responses to tensile stresses, produced ...
Angerer Wolfgang P - - 2010
We discuss the evaluation of Luria-Delbrück fluctuation experiments under Bellman-Harris models of cell proliferation. It is shown that under certain very natural assumptions concerning the life-time distributions and the offspring distributions of mutant and non-mutant cells, the suitably normed and centered number of mutants contained in a large culture of ...
Chapin Robert E - - 2009
The National Research Council's (NRC) toxicity testing vision lays out a bold future for our field. It depends heavily on computational algorithms based on the latest knowledge of cellular biochemistry and protein interaction pathways, exposing human cells to novel compounds in vitro, and being able to understand the changes seen. ...
Augusto Elisabeth F P - - 2010
Studies of a bioprocess optimization and monitoring for protein synthesis in animal cells face a challenge on how to express in quantitative terms the system performance. It is possible to have a panel of calculated variables that fits more or less appropriately the intended goal. Each mathematical expression approach translates ...
McGarry J P - - 2009
A substantial body of work has been reported in which the mechanical properties of adherent cells were characterized using compression testing in tandem with computational modeling. However, a number of important issues remain to be addressed. In the current study, using computational analyses, the effect of cell compressibility on the ...
Lin Chih-Min - - 2009
A key issue in stem cell biology is the differentiation of homogeneous stem cells towards different fates which are also organized into desired configurations. Little is known about the mechanisms underlying the process of periodic patterning. Feather explants offer a fundamental and testable model in which multi-potential cells are organized ...
Lee Min Woo - - 2009
In this article, we propose an individual-based and stochastic modeling approach that is capable of describing the bacterial cell population dynamics during a batch culture. All stochastic nature inherent in intracellular molecular level reactions and cell division processes were considered in a single model framework by embedding a sub-model describing ...
Harisi Revekka - - 2009
For the control of tumor metastasis it is important to identify chemical compounds with antimigratory potency. Agents acting against single cell and cluster type migration are necessary for successful antimetastatic therapy. In the present study, the migration of HT-1080 fibrosarcoma cells and OSCORT osteosarcoma cells was compared in a Boyden ...
Cheng Gang - - 2009
To provide theoretical guidance for the design and in vitro cultivation of bioartificial tissues, we have developed a multiscale computational model that can describe the complex interplay between cell population and mass transport dynamics that governs the growth of tissues in three-dimensional scaffolds. The model has three components: a transient ...
Zhang Tongli - - 2009
Multicellular organisms shape development and remove aberrant cells by programmed cell death ("apoptosis"). Because defective cell death (too little or too much) is implicated in various diseases (like cancer and autoimmunity), understanding how apoptosis is regulated is an important goal of molecular cell biologists. To this end, we propose a ...
Starosta Matthew S - - 2009
The FDTD method was used to simulate focused Gaussian beam propagation through multiple inhomogeneous biological cells. To our knowledge this is the first three dimensional computational investigation of a focused beam interacting with multiple biological cells using FDTD. A parametric study was performed whereby three simulated cells were varied by ...
Wood Levi Benjamin - - 2009
This paper presents a framework for controlling the development of a vascular system in an in vitro angiogenesis process. Based on online measurement of cell growth and a stochastic cell population model, a closed-loop control system is developed for regulating the process of cell migration and vascular system development. Angiogenesis ...
Fozard J A - - 2010
This work examines a 1D individual-based model (IBM) for a system of tightly adherent cells, such as an epithelial monolayer. Each cell occupies a bounded region, defined by the location of its endpoints, has both elastic and viscous mechanical properties and is subject to drag generated by adhesion to the ...
Ron Amit - - 2009
The dielectric dispersion characteristics of cellular suspensions are fundamentally determined based on the analogy to composite dielectric materials when periodically and discrete arrangement of cells is assumed. However, under native physiological conditions, when flocculation and clamping events usually occur, those assumptions are usually not valid. In the framework of this ...
Foster David V - - 2009
Multipotent stem or progenitor cells undergo a sequential series of binary fate decisions, which ultimately generate the diversity of differentiated cells. Efforts to understand cell fate control have focused on simple gene regulatory circuits that predict the presence of multiple stable states, bifurcations and switch-like transitions. However, existing gene network ...
Kim Yangjin - - 2009
Glioblastoma is the most common and the most aggressive type of brain cancer. The median survival time from the time of diagnosis is approximately one year. Invasion of glioma cells from the core tumor into the surrounding brain tissue is a major reason for treatment failure: these migrating cells are ...
Jaeger Stefan - - 2009
The emergence of new microscopy techniques in combination with the increasing resource of bioimaging data has given fresh impetus to utilizing image processing methods for studying biological processes. Cell tracking studies in particular, which are important for a wide range of biological processes such as embryonic development or the immune ...
Su Jing - - 2009
Increasingly, combinatorial libraries are used to screen large numbers of complex chemically- and physically-patterned polymers against cell response. There is a strong need to extract meaningful relationships between cell function and material surface features from these experiments. A novel high-throughput cell-material screening strategy, based upon local cell-feature analysis (LCFA) was ...
Garbuzova-Davis Svitlana - - 2009
Sanfilippo syndrome type B (MPS III B) is caused by a deficiency of alpha-N-acetylglucosaminidase enzyme (Naglu), leading to accumulation of heparan sulfate (HS), a glycosaminoglycan (GAG), within lysosomes and to eventual progressive cerebral and systemic multiple organ abnormalities. Treatment of MPS patients is mainly supportive and enzyme replacement cell therapy ...
Seet Katrina Y T - - 2009
The cell nucleus is the dominant optical scatterer in the cell. Neoplastic cells are characterized by cell nucleus polymorphism and polychromism-i.e., the nuclei exhibits an increase in the distribution of both size and refractive index. The relative size parameter, and its distribution, is proportional to the product of the nucleus ...
Anetzberger Claudia - - 2009
Quorum sensing (QS) refers to the ability of bacterial populations to read out the local environment for cell density and to collectively activate gene expression. Vibrio harveyi, one of the best characterized model organisms in QS, was used to address the question how single cells behave within a QS-activated community ...
Surovtsev Ivan V - - 2009
Self-replication is an essential attribute of life but the molecular-level mechanisms involved are not well understood. Cellular self-replication requires not only duplicating all cellular components and doubling volume and membrane area, but also replicating cellular geometry. A whole-cell modeling framework is presented in which an assumed reaction network determines both ...
Li Hui - - 2009
We have already established human xenographic models for the effect of lysophosphatidic acid (LPA) on tumor metastasis in vivo. The purpose of this work is to establish a preclinical LPA effect model in immunocompetent mice. We first characterized the mouse epithelial ovarian cancer (EOC) cell line ID8 for its responsiveness ...
Demekhin Evgeny - - 2009
The nematode sperm cell crawls by recycling major sperm protein (MSP) from dimers into subfilaments, filaments, and filament complexes, as a result of thermal writhing in the presence of hydrophobic patches. Polymerization near leading edges of the cell intercolates MSP dimers onto the tips of growing filament complexes, forcing them ...
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