abstract：:In recent years, by using modern imaging techniques, scientists have found evidence of collaboration between different types of stem cells (SCs), and proposed a bi-compartmental organization of the SC niche. Here we create a class of stochastic models to simulate the dynamics of such a heterogeneous SC niche. We consi...

journal_title：Physical biology

authors： Shahriyari L,Komarova NL

更新日期：2015-07-31 00:00:00

abstract：:The single-molecule fluorescence technique is becoming a general and mature tool to probe interactions and dynamics of biomolecules with ultra high precision and accuracy. However, nonspecific adsorption of biomolecules to the flow cells remains a major experimental riddle for the study of many complex biological syst...

journal_title：Physical biology

authors： Pan H,Xia Y,Qin M,Cao Y,Wang W

更新日期：2015-06-29 00:00:00

abstract：:Recently, major progress has been made to develop computational models to predict and explain the mechanisms and behaviors of gene regulation. Here, we review progress on how these mechanisms and behaviors have been interpreted with analog models, where cell properties continuously modulate transcription, and digital ...

journal_title：Physical biology

authors： Munsky B,Neuert G

更新日期：2015-06-18 00:00:00

abstract：:Cells moving on a two dimensional substrate generate motion by polymerizing actin filament networks inside a flat membrane protrusion. New filaments are generated by branching off existing ones, giving rise to branched network structures. We investigate the force-extension relation of branched filaments, grafted on an...

journal_title：Physical biology

authors： Razbin M,Falcke M,Benetatos P,Zippelius A

更新日期：2015-06-04 00:00:00

abstract：:We study diffusion of macromolecules in a crowded cytoplasm-like environment, focusing on its dependence on composition and its crossover to the anomalous subdiffusion. The crossover and the diffusion itself depend on both the volume fraction and the relative concentration of macromolecules. In accordance with previou...

journal_title：Physical biology

authors： Kondrat S,Zimmermann O,Wiechert W,von Lieres E

更新日期：2015-05-28 00:00:00

abstract：:Lipid molecules, structural components of biomembranes, have been proposed for an important role in membrane fusion. Through various techniques based on a protein-reconstituted vesicle-vesicle fusion system, we investigated the influence of several lipid molecules on different stages of a yeast soluble N-ethylmaleimid...

journal_title：Physical biology

authors： Lai Y,Zhao L,Bu B,Lou X,Li D,Ji B,Liu J,Diao J,Shin YK

更新日期：2015-04-21 00:00:00

abstract：:Successful biological development via spatial regulation of cell differentiation relies on the action of multiple signaling molecules that are known as morphogens. It is now well-established that signaling molecules create non-uniform concentration profiles, morphogen gradients, that activate different genes, leading ...

journal_title：Physical biology

authors： Teimouri H,Kolomeisky AB

更新日期：2015-04-17 00:00:00

abstract：:This report presents a simple model that describes the motion of a single Dictyostelium discoideum cell exposed to a traveling wave of cyclic adenosine monophosphate (cAMP). The model incorporates two types of responses to stimulation by cAMP: the changes in the polarity and motility of the cell. The periodic change i...

journal_title：Physical biology

authors： Ishiwata R,Iwasa M

更新日期：2015-03-19 00:00:00

abstract：:The mechanical behavior of living murine T-lymphocytes was assessed by atomic force microscopy (AFM). A robust experimental procedure was developed to overcome some features of lymphocytes, in particular their spherical shape and non-adherent character. The procedure included the immobilization of the lymphocytes on a...

journal_title：Physical biology

authors： Daza R,Cruces J,Arroyo-Hernández M,Marí-Buyé N,De la Fuente M,Plaza GR,Elices M,Pérez-Rigueiro J,Guinea GV

更新日期：2015-03-19 00:00:00

abstract：:To address the issue of extracting useful information from large data-set of large scale networks of neurons, we propose an algorithm that involves both algebraic-statistical and topological tools. We investigate the electrical behavior of in vitro cortical assemblies both during spontaneous and stimulus-evoked activi...

journal_title：Physical biology

authors： Pirino V,Riccomagno E,Martinoia S,Massobrio P

更新日期：2015-01-05 00:00:00

abstract：:We propose a three-dimensional mechanical model of embryonic tissue dynamics. Mechanically coupled adherent cells are represented as particles interconnected with elastic beams which can exert non-central forces and torques. Tissue plasticity is modeled by a stochastic process consisting of a connectivity change (addi...

journal_title：Physical biology

authors： Czirok A,Isai DG

更新日期：2014-12-15 00:00:00

abstract：:Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used to analyze host-microorganism relationships, as well as most of the ecological theories proposed to explain coevol...

journal_title：Physical biology

authors： Mukherjee S,Weimer KE,Seok SC,Ray WC,Jayaprakash C,Vieland VJ,Swords WE,Das J

更新日期：2014-12-04 00:00:00

abstract：:The morphological symmetry of the division process of Escherichia coli is well-known. Recent studies verified that, in optimal growth conditions, most divisions are symmetric, although there are exceptions. We investigate whether such morphological asymmetries in division introduce functional asymmetries between siste...

journal_title：Physical biology

authors： Gupta A,Lloyd-Price J,Oliveira SM,Yli-Harja O,Muthukrishnan AB,Ribeiro AS

更新日期：2014-11-10 00:00:00

abstract：:When the author arrived in Berkeley, in the mid 1970s, to study Biophysics he soon felt as if he was engaging himself in a somewhat marginal activity. Biology was then entering another of its cyclical periods of annotation that was to culminate with the human genome project. Two decades later, however, at the end of t...

journal_title：Physical biology

authors： Bustamante CJ

更新日期：2014-10-08 00:00:00

abstract：:Neurofilaments are transported along axons stochastically in a stop-and-go manner, cycling between brief bouts of rapid movement and pauses that can vary from seconds to hours in length. Presently the only way to analyze neurofilament pausing experimentally on both long and short time scales is the pulse-escape method...

journal_title：Physical biology

authors： Li Y,Brown A,Jung P

更新日期：2014-04-01 00:00:00

abstract：:With the development of next-generation sequencing technologies, many large scale experimental efforts aim to map genotypic variability among individuals. This natural variability in populations fuels many fundamental biological processes, ranging from evolutionary adaptation and speciation to the spread of genetic di...

journal_title：Physical biology

authors： Razo-Mejia M,Boedicker JQ,Jones D,DeLuna A,Kinney JB,Phillips R

更新日期：2014-04-01 00:00:00

abstract：:Growing evidence suggests that critical cellular processes are profoundly influenced by the cross talk between extracellular nanomechanical forces and the material properties of the cellular microenvironment. Although many studies have examined either the effect of nanomechanical forces or the material properties of t...

journal_title：Physical biology

authors： Al-Rekabi Z,Pelling AE

更新日期：2013-12-01 00:00:00

abstract：:Neuronal cells change their growth properties in response to external physical stimuli such as variations in external temperature, stiffness of the growth substrate, or topographical guidance cues. Detailed knowledge of the mechanisms that control these biomechanical responses is necessary for understanding the basic ...

journal_title：Physical biology

authors： Spedden E,Kaplan DL,Staii C

更新日期：2013-10-01 00:00:00

abstract：:Messenger RNA (mRNA) encodes a sequence of amino acids by using codons. For most amino acids, there are multiple synonymous codons that can encode the amino acid. The translation speed can vary from one codon to another, thus there is room for changing the ribosome speed while keeping the amino acid sequence and hence...

journal_title：Physical biology

authors： Mitarai N,Pedersen S

更新日期：2013-10-01 00:00:00

abstract：:The important role of cation-chloride co-transporters in epilepsy is being supported by an increasing number of investigations. However, enormous complexity is involved since the action of these co-transporters has effects on the ionic homeostasis influencing directly the neuronal excitability and the tissue propensit...

journal_title：Physical biology

authors： Lopes MR,Santos LE,Rodrigues AM,Duarte MA,Infantosi AF,Scorza FA,Arida RM,Madureira AP,da Silveira GA,dos Santos IC,Cavalheiro EA,de Almeida AC

更新日期：2013-10-01 00:00:00

abstract：:Thrombosis accounts for 80% of deaths in patients with diabetes mellitus. Diabetic patients demonstrate tortuous microvessels and larger than normal platelets. Large platelets are associated with increased platelet activation and thrombosis, but the physical effects of large platelets in the microscale processes of th...

journal_title：Physical biology

authors： Chesnutt JK,Han HC

更新日期：2013-10-01 00:00:00

abstract：:This paper gives an overview of the coarse-grained models of phospholipids recently developed by the authors in the frame of a hybrid particle-field molecular dynamics technique. This technique employs a special class of coarse-grained models that are gaining popularity because they allow simulations of large scale sy...

journal_title：Physical biology

authors： Milano G,Kawakatsu T,De Nicola A

更新日期：2013-08-01 00:00:00

abstract：:Gravity or ultracentrifuge settling of colloidal particles and macromolecules usually involves several disperse species, either because natural and industrial colloids display a large size polydispersity, or because additives are put in on purpose to allow for density-based fractionation of the suspension. Such 'macro...

journal_title：Physical biology

authors： Piazza R,Buzzaccaro S,Secchi E,Parola A

更新日期：2013-08-01 00:00:00

abstract：:When motile cells come into contact with one another their motion is often considerably altered. In a process termed contact inhibition of locomotion (CIL) cells reshape and redirect their movement as a result of cell-cell contact. Here we describe a mathematical model that demonstrates that CIL alone is sufficient to...

journal_title：Physical biology

authors： Coburn L,Cerone L,Torney C,Couzin ID,Neufeld Z

更新日期：2013-08-01 00:00:00

abstract：:Based on the experimental evidence that translating ribosomes stabilize the mRNAs, we introduce and study a theoretical model for the dynamic shielding of mRNA by ribosomes. We present an improved fitting of published decay assay data in E. coli and show that only one third of the decay patterns are exponential. Our n...

journal_title：Physical biology

authors： Deneke C,Lipowsky R,Valleriani A

更新日期：2013-08-01 00:00:00

abstract：:By combining optical tweezers-assisted dynamic force spectroscopy experiments with fluorescence activated cell sorting (FACS), we demonstrate a new approach to reducing the data variance in measuring receptor-ligand interactions on a single molecule level by ensuring similar coating densities. Therefore, the carboxyfl...

journal_title：Physical biology

authors： Stangner T,Singer D,Wagner C,Gutsche C,Ueberschär O,Hoffmann R,Kremer F

更新日期：2013-08-01 00:00:00

abstract：:Modeling the spatiotemporal dynamics of biochemical reaction systems at single-molecule resolution has become feasible with the increase of computing power and is applied especially to cellular signal transduction. For an association reaction the two molecules have to be in contact. Hence, a physically faithful model ...

journal_title：Physical biology

authors： Klann M,Koeppl H

更新日期：2013-08-01 00:00:00

abstract：:Epigenetic mechanisms of silencing via heritable chromatin modifications play a major role in gene regulation and cell fate specification. We consider a model of epigenetic chromatin silencing in budding yeast and study the bifurcation diagram and characterize the bistable and the monostable regimes. The main focus of...

journal_title：Physical biology

authors： Dayarian A,Sengupta AM

更新日期：2013-06-01 00:00:00

abstract：:Directed cell migration often involves at least two types of cell motility that include multicellular streaming and chain migration. However, what is unclear is how cell contact dynamics and the distinct microenvironments through which cells travel influence the selection of one migratory mode or the other. The embryo...

journal_title：Physical biology

authors： Wynn ML,Rupp P,Trainor PA,Schnell S,Kulesa PM

更新日期：2013-06-01 00:00:00

abstract：:Bistable regulatory elements enhance heterogeneity in cell populations and, in multicellular organisms, allow cells to specialize and specify their fate. Our study demonstrates that in a system of bistable genetic switch, the noise characteristics control in which of the two epigenetic attractors the cell population w...

journal_title：Physical biology

authors： Jaruszewicz J,Lipniacki T

更新日期：2013-06-01 00:00:00

abstract：:Cells often have tens of thousands of receptors, even though only a few activated receptors can trigger full cellular responses. Reasons for the overabundance of receptors remain unclear. We suggest that, under certain conditions, the large number of receptors can result in a competition among receptors to be the firs...

journal_title：Physical biology

authors： Cheng X,Merchan L,Tchernookov M,Nemenman I

更新日期：2013-06-01 00:00:00

abstract：:Oncolytic virotherapy-the use of viruses that specifically kill tumor cells-is an innovative and highly promising route for treating cancer. However, its therapeutic outcomes are mainly impaired by the host immune response to the viral infection. In this paper, we propose a multiscale mathematical model to study how t...

journal_title：Physical biology

authors： Paiva LR,Silva HS,Ferreira SC,Martins ML

更新日期：2013-04-01 00:00:00

abstract：:Traditional experimental biology has provided a mechanistic understanding of cancer in which the malignancy develops through the acquisition of mutations that disrupt cellular processes. Several drugs developed to target such mutations have now demonstrated clinical value. These advances are unequivocal testaments to ...

journal_title：Physical biology

authors： Stites EC

更新日期：2013-04-01 00:00:00

abstract：:We report self-consistent Brownian dynamics simulations of a simple electrostatic model of the selectivity filters (SF) of calcium ion channels. They reveal regular structure in the conductance and selectivity as functions of the fixed negative charge Qf at the SF. With increasing Qf, there are distinct regions of hig...

journal_title：Physical biology

authors： Kaufman I,Luchinsky DG,Tindjong R,McClintock PV,Eisenberg RS

更新日期：2013-04-01 00:00:00

abstract：:Branching morphogenesis is a widely spread phenomenon in nature. In organogenesis, it results from the inhomogeneous growth of the epithelial sheet, leading to its repeated branching into surrounding mesoderm. Lung morphogenesis is an emblematic example of tree-like organogenesis common to most mammals. The core signa...

journal_title：Physical biology

authors： Clément R,Douady S,Mauroy B

更新日期：2012-12-01 00:00:00

abstract：:Cancer may result from localized failure of instructive cues that normally orchestrate cell behaviors toward the patterning needs of the organism. Steady-state gradients of transmembrane voltage (V(mem)) in non-neural cells are instructive, epigenetic signals that regulate pattern formation during embryogenesis and mo...

journal_title：Physical biology

authors： Lobikin M,Chernet B,Lobo D,Levin M

更新日期：2012-12-01 00:00:00

abstract：:Tumor metastasis involves a progressive loss of tissue architecture and dissolution of structural boundaries between the epithelium and connective tissue. The basement membrane (BM), a specialized network of extracellular matrix proteins forms a barrier that physically restricts pre-invasive lesions such that they rem...

journal_title：Physical biology

authors： Tanner K

更新日期：2012-12-01 00:00:00

abstract：:Electrostatic interaction is the driving force for the encapsulation by virus coat proteins of nanoparticles such as quantum dots, gold particles and magnetic beads for, e.g., imaging and therapeutic purposes. In recent experimental work, Daniel et al (2010 ACS Nano 4 3853-60) found the encapsulation efficiency to sen...

journal_title：Physical biology

authors： Lin HK,van der Schoot P,Zandi R

更新日期：2012-12-01 00:00:00

abstract：:Bidirectional cargo transport by molecular motors in cells is a complex phenomenon in which the cargo (usually a vesicle) alternately moves in retrograde and anterograde directions. In this case, teams of oppositely pulling motors (e.g., kinesin and dynein) bind to the cargo, simultaneously, and 'coordinate' their act...

journal_title：Physical biology

authors： Bhat D,Gopalakrishnan M

更新日期：2012-08-01 00:00:00

abstract：:The spatial patterning of three cell fates in a row of competent cells is exemplified by vulva development in the nematode Caenorhabditis elegans. The intercellular signaling network that underlies fate specification is well understood, yet quantitative aspects remain to be elucidated. Quantitative models of the netwo...

journal_title：Physical biology

authors： Félix MA

更新日期：2012-08-01 00:00:00