Abstract：
:We develop an elastic-isotropic rod model for twisted DNA in the plectonemic regime. We account for DNA elasticity, electrostatic interactions and entropic effects due to thermal fluctuations. We apply our model to single-molecule experiments on a DNA molecule attached to a substrate at one end, while subjected to a tensile force and twisted by a given number of turns at the other end. The free energy of the DNA molecule is minimized subject to the imposed end rotations. We compute values of the torsional stress, radius, helical angle and key features of the rotation-extension curves. We also include in our model the end loop energetic contributions and obtain estimates for the jumps in the external torque and extension of the DNA molecule seen in experiments. We find that, while the general trends seen in experiments are captured simply by rod mechanics, the details can be accounted for only with the proper choice of electrostatic and entropic interactions. We perform calculations with different ionic concentrations and show that our model yields excellent fits to mechanical data from a large number of experiments. Our methods also allow us to consider scenarios where we have multiple plectonemes or a series of loops forming in the DNA instead of plectonemes. For a given choice of electrostatic and entropic interactions, we find there is a range of forces in which the two regimes can coexist due to thermal motion.
journal_name
Acta Biomaterjournal_title
Acta biomaterialiaauthors
Argudo D,Purohit PKdoi
10.1016/j.actbio.2012.01.030subject
Has Abstractpub_date
2012-07-01 00:00:00pages
2133-43issue
6eissn
1742-7061issn
1878-7568pii
S1742-7061(12)00046-3journal_volume
8pub_type
杂志文章abstract：:Decellularized allografts offer potential as heart valve substitutes and scaffolds for cell seeding. The effects of decellularization on the quasi-static and time-dependent mechanical behavior of the pulmonary valve leaflet under biaxial loading conditions have not previously been reported in the literature. In the cu...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2012.03.047
更新日期：2012-07-01 00:00:00
abstract：:Polymeric ultra-thin films (nanosheets) possess unique properties that make them suitable materials for various biomedical applications. In our previous study, we assessed the use of an antibiotic (tetracycline, TC)-loaded nanosheet (or "TC-nanosheet") for the treatment of gastrointestinal tissue defects. The nanoshee...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2012.04.019
更新日期：2012-08-01 00:00:00
abstract：:The fibrils in the bone matrix are glued together by extracellular matrix proteins to form laminated structures (osteons) to provide elasticity and a supportive substrate for osteogenesis. The objective of this work was to investigate material properties and osteogenic differentiation of bone marrow stromal (BMS) cell...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2009.12.003
更新日期：2010-06-01 00:00:00
abstract：:Strombus gigas (conch) shells and Tridacna gigas (Giant clam) shells have dense, tailored structures that impart excellent mechanical properties to these shells. In this investigation, conch and clam seashells were converted to hydroxyapatite (HAP) by a hydrothermal method at different temperatures and for different c...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2007.06.003
更新日期：2007-11-01 00:00:00
abstract：:The development of polyelectrolyte multilayered coatings on magnesium alloy substrates that can be used for controlled delivery of growth factors and required biomolecules from the surface of these degradable implants could have a significant impact in the field of bone tissue regeneration. The current work reports on...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2013.05.013
更新日期：2013-11-01 00:00:00
abstract：:Extracellular matrix microfibrils are critical components of connective tissues with a wide range of mechanical and cellular signalling functions. Collagen VI is a heteromeric network-forming collagen which is expressed in tissues such as skin, lung, blood vessels and articular cartilage where it anchors cells into th...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2016.12.023
更新日期：2017-04-01 00:00:00
abstract：:Postoperative adhesion is a relevant clinical problem that causes a variety of clinical complications after abdominal surgery. The objective of this study is to develop a liquid-type antiadhesion agent and evaluate its efficacy in preventing tissue adhesion in a rat peritoneal adhesion model. The liquid-type agent was...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2018.12.009
更新日期：2019-01-15 00:00:00
abstract：:Titanium (Ti) has been widely used as an implant material due to the excellent biocompatibility and corrosion resistance of its oxide surface. Biomaterials must be sterile before implantation, but the effects of sterilization on their surface properties have been less well studied. The effects of cleaning and steriliz...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2011.11.026
更新日期：2012-05-01 00:00:00
abstract：:Controlling the release of recombinant adeno-associated virus (rAAV) vectors from biocompatible materials is a novel, attractive approach to increase the residence time and effectiveness of a gene carrier at a defined target site. Self-assembling peptides have an ability to form stable hydrogels and encapsulate cells ...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2015.02.013
更新日期：2015-05-01 00:00:00
abstract：:The gradient localization of biological cues is of paramount importance to guide directional migration of cells. In this study, poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate)-block- poly(2-hydroxyethyl methacrylate) (P(HEMA-co-GMA)-b-PHEMA) brushes with a uniform underneath P(HEMA-co-GMA) layer and a gradi...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2018.05.046
更新日期：2018-07-15 00:00:00
abstract：:Analytical protocol greatly influences the measurement of human serum albumin (HSA) adsorption to commercial expanded polytetrafluororethylene (ePTFE) exhibiting superhydrophobic wetting properties. Degassing of buffer solutions and evacuation of ePTFE adsorbent to remove trapped air immediately prior to contact with ...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2008.11.003
更新日期：2009-06-01 00:00:00
abstract：:In the present study, the density functional theory implemented in the Vienna Ab-initio Simulation Package has been used to investigate the alloying effects of different elements of calcium, zinc, yttrium, aluminum and iron when introduced in the Mg crystal lattice. In particular, studies have been conducted to invest...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2009.08.016
更新日期：2010-05-01 00:00:00
abstract：:The quest for predictive tumor markers for osteosarcoma (OS) has not well progressed over the last two decades due to a lack of preclinical models. The aim of this study was to investigate if microenvironmental modifications in an original humanized in vivo model alter the expression of OS tumor markers. Human bone mi...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2019.02.051
更新日期：2019-04-15 00:00:00
abstract：:Hydrogel microspheres with the capability to interact with charged species such as various drugs by ion-exchange processes are useful in a variety of biomedical applications. Such systems have been developed to allow active loading of the microsphere with chemotherapeutic agents in the hospital pharmacy for subsequent...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2017.02.013
更新日期：2017-04-15 00:00:00
abstract：:There is increasing interest in the development of new tissue engineering strategies to deliver cells and bioactive agents encapsulated in a biodegradable matrix through minimally invasive procedures. The present work proposes to combine chitosan-beta-glycerophosphate salt formulations with bioactive glass nanoparticl...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2008.08.006
更新日期：2009-01-01 00:00:00
abstract：:Meniscal tears are the most common orthopedic injuries to the human body, yet the current treatment of choice is a partial meniscectomy, which is known to lead to joint degeneration and osteoarthritis. As a result, there is a significant clinical need to develop materials capable of restoring function to the meniscus ...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2014.05.004
更新日期：2014-08-01 00:00:00
abstract：:Two enzymes, thrombin and transglutaminase, both participate in the formation of fibrin networks and contribute to the mechanical strength of biogels. A theoretical model built from the available kinetic data showed that a competition may take place between the two enzymes for their common substrate, fibrinogen. To ev...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2009.08.001
更新日期：2010-02-01 00:00:00
abstract：:Introducing nanoroughness on various biomaterials has been shown to profoundly effect cell-material interactions. Similarly, physical forces act on a diverse array of cells and tissues. Particularly in bone, the tissue experiences compressive or tensile forces resulting in fluid shear stress. The current study aimed t...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2013.02.011
更新日期：2013-05-01 00:00:00
abstract：UNLABELLED:Recent studies reveal many biomaterial vaccine carriers are able to activate immunostimulatory pathways, even in the absence of other immune signals. How the changing properties of polymers during biodegradation impact this intrinsic immunogenicity is not well studied, yet this information could contribute t...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2015.12.026
更新日期：2016-03-01 00:00:00
abstract：:Peripheral arterial disease differentially affects the superficial femoral (SFA) and the popliteal (PA) arteries, but their morphometric, structural, mechanical, and physiologic differences are poorly understood. SFAs and PAs from 125 human subjects (age 13-92, average 52±17 years) were compared in terms of radii, wal...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2020.11.025
更新日期：2021-02-01 00:00:00
abstract：:Hydrogels that solidify in response to a dual, physical and chemical, mechanism upon temperature increase were fabricated and characterized. The hydrogels were based on N-isopropylacrylamide, which renders them thermoresponsive, and contained covalently cross-linkable moieties in the macromers. The effects of the macr...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2010.12.027
更新日期：2011-04-01 00:00:00
abstract：:A series of aggregation-induced emission (AIE)-based imidazolium-type ionic liquids (ILs) were designed and synthesized for bacterial killing and imaging, cell labeling, and bacterial detection in blood cells. The AIE-based ILs showed antibacterial activities against both Escherichia coli and Staphylococcus aureus. Th...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2019.07.039
更新日期：2019-10-01 00:00:00
abstract：:Bioactive materials play an important role in facilitating dental pulp repair when living dental pulp is exposed after injuries. Mineral trioxide aggregate is the currently recommended material of choice for pulp repair procedures though has several disadvantages, especially the inconvenience of handling. Little infor...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2014.08.014
更新日期：2014-12-01 00:00:00
abstract：:This paper presents a strain-mediated phenomenological corrosion model, based on the discrete finite element modelling method which was developed for use with the ANSYS Implicit finite element code. The corrosion model was calibrated from experimental data and used to simulate the corrosion performance of a WE43 magne...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2017.04.020
更新日期：2017-06-01 00:00:00
abstract：:Small intestine submucosa (SIS) has emerged as one of a number of naturally derived extracellular matrix (ECM) biomaterials currently in clinical use. In addition to clinical applications, ECM materials form the basis for a variety of approaches within tissue engineering research. In our preliminary work it was found ...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2014.08.024
更新日期：2014-12-01 00:00:00
abstract：:Gelatin and alginate derivatives possessing phenolic hydroxyl moieties (gelatin-Ph and Alg-Ph) were dissolved in aqueous solution and conjugated via horseradish peroxidase-catalyzed crosslinking, resulting in hydrogelation. The objective of creating the hydrogels was to prepare cell sheets and spherical tissues wrappe...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2013.01.037
更新日期：2013-05-01 00:00:00
abstract：:The use of hybrid pH-sensitive micelles based mainly on the (PEO)(129)(P2VP)(43)(PCL)(17) ABC miktoarm star copolymer as potential triggered drug delivery systems was investigated. Co-micellization of this star copolymer with a second copolymer labeled by a targeting ligand, i.e. biotin, on the pH sensitive block (pol...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2012.08.049
更新日期：2012-12-01 00:00:00
abstract：:Tubular collagen scaffolds have been used for the repair of damaged hollow organs in regenerative medicine, but they generally lack the ability to reversibly expand in radial direction, a physiological characteristic seen in many native tubular organs. In this study, tubular collagen scaffolds were prepared that displ...
journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2017.02.005
更新日期：2017-04-01 00:00:00
abstract：:Corneal blindness is traditionally treated by transplantation of a donor cornea, or in severe cases by implantation of an artificial cornea or keratoprosthesis. Due to severe donor shortages and the risks of complications that come with artificial corneas, tissue engineering in ophthalmology has become more focused on...
journal_title：Acta biomaterialia
pub_type： 杂志文章,评审
doi：10.1016/j.actbio.2018.01.023
更新日期：2018-03-15 00:00:00
abstract：:Hydrogels have been recognized as crucial biomaterials in the field of tissue engineering, regenerative medicine, and drug delivery applications due to their specific characteristics. These biomaterials benefit from retaining a large amount of water, effective mass transfer, similarity to natural tissues and the abili...
journal_title：Acta biomaterialia
pub_type： 杂志文章,评审
doi：10.1016/j.actbio.2017.07.028
更新日期：2017-10-15 00:00:00
