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Stable Scaffold (stable + scaffold)

Distribution by Scientific Domains

Chemistry	50%

Selected Abstracts

Blending Chitosan with Polycaprolactone: Porous Scaffolds and Toxicity

MACROMOLECULAR BIOSCIENCE, Issue 9-10 2007
Aparna R. Sarasam
Abstract The preparation and characterization of porous scaffolds from chitosan-PCL blends by freeze extraction, freeze gelation and freeze drying is reported. Using freeze extraction, stable structures were obtained only from PCL, but these were not porous. No stable scaffolds were obtained using the freeze gelation process. Stable scaffolds of chitosan/PCL mixtures could not be obtained using 77% acetic acid by any of these techniques. With 25% aqueous acetic acid, stable scaffolds of chitosan/PCL mixtures were obtained by the freeze drying technique. The stability and pore morphology of freeze dried scaffolds were dependent on the relative mass ratio of chitosan and PCL. A chorioallantoic membrane assay showed that formed 3D chitosan/PCL mixtures were not toxic to vasculature. [source]

Synthesis of heterotrimeric collagen peptides containing the ,1,1 integrin recognition site of collagen type IV

JOURNAL OF PEPTIDE SCIENCE, Issue 5 2002
Barbara Saccá
Abstract Collagen type IV provides a biomechanically stable scaffold into which the other constituents of basement membranes are incorporated, but it also plays an important role in cell adhesion. This occurs with collagen type IV mainly via the ,1,1 integrin, and the proposed epitope involved in this type of collagen/integrin interaction corresponds to a non-sequential R/Xaa/D motif, where the arginine and aspartate residues are provided by the ,2 and ,1 chains of the collagen molecule, respectively. Since the stagger of the three , chains in native collagen type IV is still unknown and different alignments of the chains lead to different spatial epitopes, two heterotrimeric collagen peptides containing the natural 457,469 sequences of the cell adhesion site were synthesized in which the single chains were assembled via disulfide bonds into the two most plausible ,1,2,1, and ,2,1,1, registers. The differentiated triple-helical stabilities of the two heterotrimers suggest a significant structural role of the chain register in collagen, although the binding to ,1,1 integrin is apparently less affected as indicated by preliminary experiments. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd. [source]

The effect of the side chain length of Asp and Glu on coordination structure of Cu2+ in a de novo designed protein

BIOPOLYMERS, Issue 11 2009
Daigo Shiga
Abstract Metal ions in proteins are important not only for the formation of the proper structures but also for various biological activities. For biological functions such as hydrolysis and oxidation, metal ions often adopt unusual coordination structures. We constructed a stable scaffold for metal binding to create distorted metal coordination structures. A stable four stranded ,-helical coiled-coil structure was used as the scaffold, and the metal binding site was in the cavity created at the center of the structure. Two His residues and one Asp or Glu residue were used to coordinate the metal ions, AM2D and AM2E, respectively. Cu2+ bound to AM2D with an equatorial planar coordination structure with two His, one Asp, and H2O as detected by electron spin resonance and UV spectral analyzes. On the other hand, Cu2+ had a slightly distorted square planar structure when it bound two His and Glu in AM2E, due to the longer side-chain of the Glu residue as compared to the Asp residue. Computational analysis also supported the distorted coordination structure of Cu2+ in AM2E. This construct should be useful to create various coordinations of metal ions for catalytic functions. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 907,916, 2009. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source]