Andrea Morelli, Dario Puppi, Federica Chiellini^*

Journal of Renewable Materials, Vol.1, No.2, pp. 83-112, 2013, DOI:10.7569/JRM.2012.634106

Abstract Polymers, particularly those susceptible to undergoing biodegradation under physiological environments, can be considered the materials of choice for biomedical applications such as tissue engineering, regenerative medicine, and controlled and targeted drug delivery. The development of these relatively new fi elds of biomedical research represents the driving force towards the exploitation of renewable resources for the obtainment of biobased polymeric biomaterials. This perspective article reports on the biomedical applications of three major categories of biobased polymeric materials obtained from renewable resources, namely, polysaccharides, proteins and polyesters of natural origins. Particular emphasis is given to biobased polymers More >

Idalba A. Hidalgo A.^∗, Felipe Sojo^†, Francisco Arvelo^†, Marcos A. Sabino^∗,‡

Molecular & Cellular Biomechanics, Vol.10, No.2, pp. 85-105, 2013, DOI:10.3970/mcb.2013.010.085

Abstract The electrospinning technique is a method used to produce nano and microfibers using the influence of electrostatic forces. Porous three dimensional networks of continuous and interconnected fibers as scaffolds were obtained from a poly (lactic acid) solution. The concentration of the polymeric solution, 12.5% m/w, as well as the conditions of voltage (V=11kV) and tip-metallic collector distance (H=13cm) were established to develop these scaffolds through the electrospinning process. The characteristics of the scaffolds, such as fiber diameter, sintering and the biomimetics of the characteristics of a native extra cellular matrix were verified by Scanning Electron More >

Mohammad Izadifar^a,b,*, Xiongbiao Chen^a,b

Frontiers in Heat and Mass Transfer, Vol.3, No.4, pp. 1-7, 2012, DOI:10.5098/hmt.v3.4.3004

Abstract Heat can be potentially used for accelerating biodegradation of implanted tissue engineered scaffolds. Cyclic and continuous radio frequency (RF) heating was applied to implanted chitosan and alginate scaffolds at 4 applied voltages, 3 frequencies, and 2 thermally conditioning environments. A 3D finite element model was developed to simulate the RF treatment. A uniform RF heating was achieved at the scaffold top. For alginate, voltage was the only significant RF heating factor while both frequency and voltage significantly affected RF heating of chitosan. Less temperature gradient across the scaffold was achieved at a conditioning environment at More >

BIOCELL, Vol.36, Suppl.S, pp. 1-14, 2012

Abstract This article has no abstract. More >

RANA IMANI¹, SHAHRIAR HOJJATI EMAMI¹, HOSSEIN FAKHRZADEH², NAFISEH BAHEIRAEI¹, ALI M SHARIFI^{* 2,3,4}

BIOCELL, Vol.36, No.1, pp. 37-45, 2012, DOI:10.32604/biocell.2012.36.037

Abstract The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of regeneration. Preparation of cell aggregates is one of the important steps in 3D tissue engineering technology, particularly in organ printing. Two simple methods, hanging drop (HD) and conical tube (CT) were utilized to prepare cell aggregates. The size and viability of the aggregates obtained at different initial cell densities and pre-culture duration were compared. The proliferative ability of the cell aggregates and their ability to spread in culture plates were also… More >

R. Khanna^1,2, D. R. Katti¹, K. S. Katti¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.6, pp. 530-556, 2012, DOI:10.3970/cmes.2012.087.530

Abstract Here we report a new in situ nanoindentation technique developed to evaluate the composite mechanical behavior of cell-biomaterial construct under physiological conditions over the time scale of bone nodule generation. Using this technique, mechanical behavior of osteoblast cell-substrate interfaces on tissue engineered materials (chitosan-polygalacturonic acid-nanohydroxyapatite (CPH) films) is investigated. Mechanical behavior of cells in the elastic regime over the time scale of cell adhesion (1 day), proliferation (4 days), development (8 days) and maturation (22 days) of bone nodules is evaluated. Our results indicate that the elastic properties of flat cells are higher (indicating stiffer… More >

K.W. Luczynski¹, A. Dejaco¹, O. Lahayne¹, J. Jaroszewicz², W.Swieszkowski², C. Hellmich¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.6, pp. 505-529, 2012, DOI:10.3970/cmes.2012.087.505

Abstract A 71 volume-% macroporous tissue engineering scaffold made of poly-l-lactide (PLLA) with 10 mass-% of pseudo-spherical tri-calcium phosphate (TCP) inclusions (exhibiting diameters in the range of several nanometers) was microCT-scanned. The corresponding stack of images was converted into regular Finite Element (FE) models consisting of around 100,000 to 1,000,000 finite elements. Therefore, the attenuation-related, voxel-specific grey values were converted into TCP-contents, and the latter, together with nanoindentation tests,entered a homogenization scheme of the Mori-Tanaka type, as to deliver voxel-specific (and hence, finite element-specific) elastic properties. These FE models were uniaxially loaded, giving access to the… More >

G. Mattei^1,2, A. Tirella^1,2, A. Ahluwalia^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.6, pp. 483-504, 2012, DOI:10.3970/cmes.2012.087.483

Abstract Biological function is intricately linked with structure. Many biological structures are characterised by functional spatially distributed gradients in which each layer has one or more specific functions to perform. Reproducing such structures is challenging, and usually an experimental trial-and-error approach is used. In this paper we investigate how the gravitational sedimentation of discrete solid particles (secondary phase) within a primary fluid phase with a time-varying dynamic viscosity can be used for the realisation of stable and reproducible continuous functionally graded materials (FGMs). Computational models were used to simulate the distribution of a particle phase in… More >

Hana Chang^*, Melissa L. Knothe Tate^∗,†,‡

Molecular & Cellular Biomechanics, Vol.8, No.4, pp. 297-318, 2011, DOI:10.3970/mcb.2011.008.297

Abstract In the preceding study (Part A), we showed that prescribed seeding conditions as well as seeding density can be used to subject multipotent stem cells (MSCs) to volume changing stresses and that changes in volume of the cell are associated with changes in shape, but not volume, of the cell nucleus. In the current study, we aim to control the mechanical milieu of live cells using these prescribed seeding conditions concomitant to delivery of shape changing stresses via fluid flow, while observing adaptation of the cytoskeleton, a major cellular transducer that modulates cell shape, stiffness… More >

Joshua A. Zimmermann^*, Melissa L. Knothe Tate^∗,†,‡

Molecular & Cellular Biomechanics, Vol.8, No.4, pp. 275-296, 2011, DOI:10.3970/mcb.2011.008.275

Abstract Shape and fate are intrinsic manifestations of form and function at the cell scale. Here we hypothesize that seeding density and protocol affect the form and function of live embryonic murine mesenchymal stem cells (MSCs) and their nuclei. First, the imperative for study of live cells was demonstrated in studies showing changes in cell nucleus shape that were attributable to fixation per se. Hence, we compared live cell and nuclear volume and shape between groups of a model MSC line (C3H10T1/2) seeded at, or proliferated from 5,000 cells/cm2 to one of three target densities to… More >