Download or read book Cell Adhesion Biophysics on Dynamic Polymer Constructs written by Andreas P. Kourouklis and published by . This book was released on 2015 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: The biophysical characteristics of cell adhesion from single protein to cell length scales have primarily been studied using purely elastic substrates. However, natural extracellular matrix (ECM) is viscoelastic and contains mobile components. In this work, we combined chemistry and cell biology tools to design and characterize laterally mobile viscoelastic polymer films that promote receptor-specific cell adhesion. Moreover, we used amphiphilic block copolymers that are end-labeled with RGD peptide ligands to allow for integrin-mediated cell adhesion. The addition of a trace hydrophobic homopolymer in the supported bilayer block-copolymer films is used to tune the lateral mobility of the films. NIH 3T3 fibroblasts demonstrate a non-linear spreading response against the mobility of the RGD-displaying polymer films. Employing immunostaining and adhesion strength assays, we decoupled the partial contributions of focal adhesions (FA) and integrin-RGD complexes on cell adhesion. Furthermore, we employed these biomimetic polymer platforms to investigate the importance of viscous dissipation within the extracellular substrate and its connection to cell-surface receptors. Our results suggest that cells preferentially use avb3 and a5b1 integrins to control spreading and polarization in response to mechanical properties of their substrate. In order to further control the spatial presentation of biochemical molecules on mechanically-tunable polymer substrates, we successfully transferred fibronectin patterns on bilayer polymer films. We showed that NIH 3T3 fibroblasts spreading and adhesion features depend on the mechanical properties of these hybrid materials even in the presence of spatially and chemically identical biochemical signals. Overall, the present work demonstrates the potential of amphiphilic block copolymers to form artificial substrates that can capture a key feature of cell-ECM interactions: specifically, the ability of cells to induce changes in the substrate over time. Furthermore, it highlights the need for future studies on cell-substrate interactions that simultaneously consider the time-dependent mechanical properties of the ECM, the spatial characteristics of ligand presentation, and the receptor-mediated intracellular signaling.
Download or read book PHYSICAL BASIS OF CELL CELL ADHESION written by Pierre Bongrand and published by Springer. This book was released on 1988-07-31 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Present book is aimed at providing a readable account of physical methods and results required to measure cell adhesion and interpret experimental data. Since on the one hand readability seemed a major quality for a book, and on the other hand, the problems posed referred to a wide range of domains of physics, chemistry, and biology, completeness had to sacrificed. Indeed, a whole book would not suffice to quote the relevant literature (and many more authors would be required to have read it). Hence, only a limited number of topics were selected for reliability of methods, availability of enough experimental results to illustrate basic conception or potential use in the future. These were discussed in three sections.
Download or read book Extracellular Matrix Protocols written by Charles Streuli and published by Springer Science & Business Media. This book was released on 2008-02-05 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is now widely accepted that much of the dynamic function of cells and tissues is regulated from outside the cell by the extracellular matrix. In ad- tion to its conventional role in providing a scaffold for building tissues, the extracellular matrix acts as a directional highway for cellular movement and provides instructional information for promoting survival, proliferation, and differentiation. Indeed, the extracellular matrix is beginning to take a starring role in the choreography of cell and tissue function. The diverse roles of the extracellular matrix are reflected in its highly complicated structure, consisting of an ever increasing number of components. Yet the mechanisms of extracellular matrix assembly and how they influences cell behavior are only just beginning to be understood. In order to solve these problems new methodologies are, of necessity, being developed. Many of these technologies are highly sophisticated and are currently available only in a ha- ful of laboratories. However, we believe that they can readily be transported and established by other researchers. Thus, the purpose of Extracellular Matrix Protocols is to present some of these complicated techniques in a style that is relatively easy to reproduce.
Download or read book The Analysis of Cell biomaterial Interaction by Advanced Experimental Techniques as the Basis for Biocompatibility Studies of Polymers written by Rok Podlipec and published by . This book was released on 2015 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last two decades have been determined by the development in the field of tissue engineering. Beside the constant progress in new biomaterials and scaffold fabrication methods, currently the main focus is to understand scaffolds biocompatibility. In our thesis, physical aspects of scaffold biocompatibility were studied by correlating molecular to macro scale physical properties of scaffolds with cell attachment and cell growth. In order to focus on scaffold physical properties, scaffolds were prepared by the same chemical composition of natural polymer gelatin excluding biochemical effects on the cell response. Scaffold with different physical properties were obtained by changing the temperature, pH and crosslinker degree during the cryogelation and populated by the fibroblast cells. Advanced experimental biophysical methods were applied to determine the polymer mobility via electron paramagnetic resonance (EPR) with spin labelling, the scaffold mechanical properties via rheometry, dynamic mechanical analysis (DMA) and nanoindentation using atomic force microscope (AFM) and the scaffold porosity via confocal fluorescence microscopy (CFM). The anisotropy of the molecular mobility of the side chains of polymers in the crosslinked gelatin structure was found to correlate with the initial cell growth (throughout the first week) the best of all the physical properties measured. About five times less efficient cell growth was measured on the scaffolds with highly mobile, spatially nonrestricted dynamics of the polymer side chains, in comparison with cell growth on the scaffolds with the restricted rotational motion of polymers. The result indicates that cells identify and respond to the degree of polymer mobility, where partially immobile phase is necessary for efficient cell attachment and efficient cell growth. So far, the molecular mobility of polymers constituting tissue engineering materials has never been studied thoroughly with respect to its influence on cell response, and therefore may represent a new experimental approach in understanding biocompatibility. To further understand cell-scaffold interaction, the study focused also on the first events during cell attachment - bond formation between the cell surface proteins and the specific binding sites on the material. In our thesis, cell adhesion dynamics was investigated in real-time on the surfaces of gelatin scaffolds with different physical properties using spatially-controlled cell manipulation by the optical tweezers and the confocal fluorescence microscopy detection. Our goal was to elucidate, if the adhesion dynamics can be correlated with cell growth and if it can be dependent on the scaffold polymer molecular mobility. Quantitative characterization of the optical tweezers force applied during cell-scaffold adhesion analysis was done by viscous drag force calibration and dynamic cell sequential trapping of individual cells. The maximal force on a trapped cell not causing the thermal damage was measured up to 200 pN, with nearly linearly increasing force profile across the cell towards the plasma membrane. By submicron spatial resolution of cell manipulation, we managed to quantify probability of cell adhesion, cell adhesion strength and mechanism of cell attachment, including the formation of the membrane tethers, which slow down the adhesion process. Adhesion strength was classified according to the displacement of the attached cell under the force of optical tweezers measured in the direction of the scaffold surface.Cell adhesion was shown to significantly correlate with cell growth in the first days of culture, while the adhesion itself seems to be dependent on the molecular mobility of surface polymers. The result indicates that the interactions during the first seconds may markedly direct further cell response. The developed methodology for cell adhesion analysis on the surfaces of 3D scaffolds serves as a good tool to forecast scaffold biocompatibility.
Download or read book The Adhesive Interaction of Cells written by David Garrod and published by Elsevier. This book was released on 1999-03-31 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of "The Adhesive Interaction of Cells" has been to assemble a series of reviews by leading international experts embracing many of the most important recent developments in this rapidly expanding field. The purpose of all biological research is to understand the form and function of living organisms and, by comprehending the normal, to find explanations and remedies for the abnormal and for disease conditions. The molecules involved in cell adhesion are of fundamental importance to the structure and function of all multicellular organisms. In this book, the contributors focus on the systems of vertebrates, especially mammals, since these are most relevant to human disease. It would have been equally possible to concentrate on developmental processes and adhesion in lower organisms. A major function of adhesion molecules is to bind cells to each other or to the extracellular matrix, but they are much more than "glue". Adhesions in animal tissues must be dynamic-forming, persisting, or declining in regulated fashion- to facilitate the mobility and turnover of tissue cells. Moreover, the majority of adhesion molecules are transmembrane molecules and thus provide links between the cells and their surroundings. This gives rise to another major function of adhesion molecules, the capacity to transduce signals across the hydrophobic barrier imposed by the plasma membrane. Such signal transduction is crucially important to many aspects of cellular function including the regulation of cell motility, gene expression, and differentiation. The work in this book progresses through four sections. Part I discusses the four major families of adhesion molecules themselves, the integrins (Green and Humphries), the cadherins (Stappert and Kemler), the selectins (Tedder et al.) and the immunoglobulin superfamily (Simmons); part 2 considers junctional complexes involved in cell interactions: focal adhesions and adherens junctions (Ben Ze'ev), desmosomes (Garrod et al.), and tight junctions (Citi and Cordenonsi). The signaling role of adhesion molecules is the focus of part 3, through integrins and the extracellular matrix (Edwards and Streuli), through platelet adhesion (Du and Ginsberg), and in the nervous system (Hemperley). In part 4, the aim is to show how adhesive phenomena contribute to important aspects of cell behavior and human health. Leukocyte trafficking (Haskard et al.), cancer metastasis (Marshall and Hart), cell migration (Paleck et al.), and implantation and placentation (Damsky et al.) are the topics considered in depth. The different sections are, of course, not mutually exclusive: it is both undesirable and impossible to separate structure from function when considering cell adhesion. Each chapter has its unique features, but some overlap is both invevitable and valuable since it provides different perspectives on closely related topics. We hope that the whole contributes a valuable and stimulating consideration of this important topic.
Download or read book Cell Adhesion on Synthetic Polymer Substrates written by W. T. Minett and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure and Dynamics of Biopolymers written by C Nicolini and published by . This book was released on 1987-06-30 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure and Dynamics of Biopolymers written by C. Nicolini and published by Springer. This book was released on 2011-11-18 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: This NATO-ASI on BIOPOLYMERS STRUCTURE AND DYNAMICS held between 22nd June 4th July 1986 at Erice (Italy) has brought together scientists from a broad variety of biophysical disciplines - polymer physics, biophysics and physical chemistry, structure and dynamics of polynucleotides, proteins, and polysaccharides - to present the current state of knowledge in their fields, both experimental and theoretical. This Advanced Study Institute was indeed a successfull attempt to enhance the possibility of intersection of a number of research lines that currently are progressing well but are still running largely in parallel with one another: protein folding, single-polymer phase transitions, DNA condensation into liquid crystalline-like arrays, packaging in viruses, and polysaccharide gel formation. Although each phenomenon is distinctive, an awareness of similarities may lead to new ic;leas. The program has emphasized "condensed" forms of biopolymers. We are universally confronted in biology by chain polymers folded on themselves or interlinked in gel-like assemblies, whether we look at the native structure of proteins, the role of polysaccharides in connective tissue, or the genetic apparatus. A number of lectures have been devoted to condensed forms of DNA - closed circular supercoils, toruses, chromatin.
Download or read book Molecular Basis of Cell Adhesion Mechanics written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Biophysics of Cell Membranes written by Richard M. Epand and published by Springer. This book was released on 2017-09-25 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume focuses on the modulation of biological membranes by specific biophysical properties. The readers are introduced to emerging biophysical approaches that mimick specific states (like membrane lipid asymmetry, membrane curvature, lipid flip-flop, lipid phase separation) that are relevant to the functioning of biological membranes. The first chapter describes innovative methods to mimic the prevailing asymmetry in biological membranes by forming asymmetrical membranes made of monolayers with different compositions. One of the chapters illustrates how physical parameters, like curvature and elasticity, can affect and modulate the interactions between lipids and proteins. This volume also describes the sensitivity of certain ion channels to mechanical forces and it presents an analysis of how cell shape is determined by both the cytoskeleton and the lipid domains in the membrane. The last chapter provides evidence that liposomes can be used as a minimal cellular model to reconstitute processes related to the origin of life. Each topic covered in this volume is presented by leading experts in the field who are able to present clear, authoritative and up-to-date reviews. The novelty of the methods proposed and their potential for a deeper molecular description of membrane functioning are particularly relevant experts in the areas of biochemistry, biophysics and cell biology, while also presenting clear and thorough introductions, making the material suitable for students in these fields as well.
Download or read book Molecular Design of Polymer Surfaces Having Ability to Control Cell Adhesion written by K. Kataoka and published by . This book was released on 1983 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure and Dynamics of Confined Polymers written by John J. Kasianowicz and published by Springer Science & Business Media. This book was released on 2002-07-31 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers are essential to biology because they can have enough stable degrees of freedom to store the molecular code of heredity and to express the sequences needed to manufacture new molecules. Through these they perform or control virtually every function in life. Although some biopolymers are created and spend their entire career in the relatively large free space inside cells or organelles, many biopolymers must migrate through a narrow passageway to get to their targeted destination. This suggests the questions: How does confining a polymer affect its behavior and function? What does that tell us about the interactions between the monomers that comprise the polymer and the molecules that confine it? Can we design and build devices that mimic the functions of these nanoscale systems? The NATO Advanced Research Workshop brought together for four days in Bikal, Hungary over forty experts in experimental and theoretical biophysics, molecular biology, biophysical chemistry, and biochemistry interested in these questions. Their papers collected in this book provide insight on biological processes involving confinement and form a basis for new biotechnological applications using polymers. In his paper Edmund DiMarzio asks: What is so special about polymers? Why are polymers so prevalent in living things? The chemist says the reason is that a protein made of N amino acids can have any of 20 different kinds at each position along the chain, resulting in 20 N different polymers, and that the complexity of life lies in this variety.
Download or read book Physical Biology of the Cell written by Rob Phillips and published by Garland Science. This book was released on 2012-10-29 with total page 1089 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physical Biology of the Cell is a textbook for a first course in physical biology or biophysics for undergraduate or graduate students. It maps the huge and complex landscape of cell and molecular biology from the distinct perspective of physical biology. As a key organizing principle, the proximity of topics is based on the physical concepts that
Download or read book Comprehensive Biophysics written by and published by Academic Press. This book was released on 2012-04-12 with total page 3533 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biophysics is a rapidly-evolving interdisciplinary science that applies theories and methods of the physical sciences to questions of biology. Biophysics encompasses many disciplines, including physics, chemistry, mathematics, biology, biochemistry, medicine, pharmacology, physiology, and neuroscience, and it is essential that scientists working in these varied fields are able to understand each other's research. Comprehensive Biophysics, Nine Volume Set will help bridge that communication gap. Written by a team of researchers at the forefront of their respective fields, under the guidance of Chief Editor Edward Egelman, Comprehensive Biophysics, Nine Volume Set provides definitive introductions to a broad array of topics, uniting different areas of biophysics research - from the physical techniques for studying macromolecular structure to protein folding, muscle and molecular motors, cell biophysics, bioenergetics and more. The result is this comprehensive scientific resource - a valuable tool both for helping researchers come to grips quickly with material from related biophysics fields outside their areas of expertise, and for reinforcing their existing knowledge. Biophysical research today encompasses many areas of biology. These studies do not necessarily share a unique identifying factor. This work unites the different areas of research and allows users, regardless of their background, to navigate through the most essential concepts with ease, saving them time and vastly improving their understanding The field of biophysics counts several journals that are directly and indirectly concerned with the field. There is no reference work that encompasses the entire field and unites the different areas of research through deep foundational reviews. Comprehensive Biophysics fills this vacuum, being a definitive work on biophysics. It will help users apply context to the diverse journal literature offering, and aid them in identifying areas for further research Chief Editor Edward Egelman (E-I-C, Biophysical Journal) has assembled an impressive, world-class team of Volume Editors and Contributing Authors. Each chapter has been painstakingly reviewed and checked for consistent high quality. The result is an authoritative overview which ties the literature together and provides the user with a reliable background information and citation resource
Download or read book Applied Biophysics written by Thomas Andrew Waigh and published by John Wiley & Sons. This book was released on 2007-09-11 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the fundamentals of molecular biophysics, and highlights the connection between molecules and biological phenomena, making it an important text across a variety of science disciplines. The topics covered in the book include: Phase transitions that occur in biosystems (protein crystallisation, globule-coil transition etc) Liquid crystallinity as an example of the delicate range of partially ordered phases found with biological molecules How molecules move and propel themselves at the cellular level The general features of self-assembly with examples from proteins The phase behaviour of DNA The physical toolbox presented within this text will form a basis for students to enter into a wide range of pure and applied bioengineering fields in medical, food and pharmaceutical areas.
Download or read book Atomic Force Microscopy for Nanoscale Biophysics written by Mi Li and published by Elsevier. This book was released on 2023-02-15 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomic Force Microscopy for Nanoscale Biophysics: From Single Molecules to Living Cells summarizes the applications of atomic force microscopy for the investigation of biomolecules and cells. The book discusses the methodology of AFM-based biomedical detection, diverse biological systems, and the combination of AFM with other complementary techniques. These state-of-the-art chapters empower researchers to address biological issues through the application of atomic force microscopy. Atomic force microscopy (AFM) is a unique, multifunctional tool for investigating the structures and properties of living biological systems under aqueous conditions with unprecedented spatiotemporal resolution. Summarizes the recent progress of atomic force microscopy in biomedical applications Presents the methods and skills of applying atomic force microscopy Aids researchers in investigating the nanoscale biophysics of diverse biological systems
Download or read book The Cadherin Superfamily written by Shintaro T. Suzuki and published by Springer. This book was released on 2016-06-02 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an overview of the entire field of cadherin research and provides the current basic concept of cadherins. Cadherins have been widely accepted as key regulators of animal development and physiological functions, and it also has become clear that they play essential roles in various human diseases. With contributions by leading scientists, the book covers various aspects of the cadherin superfamily including the history of cadherin research, basic properties of classical cadherins as well as non-classical cadherins, cadherin-associated proteins, and the roles of cadherins in health and diseases. In addition, the book presents some contradictory results and important unanswered questions, and the authors propose their working hypotheses or future directions, to inspire future studies. This volume enables graduate students and young researchers to learn the basics and gain a comprehensive image of the cadherin superfamily, and experts in the field will easily find various topics of interest in relevant areas of study. Additionally, a list of cadherin-related diseases is included for quick reference to cadherins in human diseases.
