Peptide-protein complex from cattle sclera: Structural aspects and chaperone activity.

The influence of temperature and chaotropic agents on the spatial organization of the peptide-protein complex isolated from cattle sclera at the level of secondary structure was studied by UV, CD spectroscopy, and dynamic light scattering. It is shown that this complex has high conformational thermostability. The point of conformational thermal transition (65 °C) was determined, after which the peptide-protein complex passes into a denatured stable state.

Effect of Bioactive Peptide Complex Isolated from Bovine Serum on Proliferation and Migration of Mesenchymal Stromal Cells In Vitro and Reparation of Bone Defects In Vivo.

We studied the effect of a bioactive peptide complex isolated from bovine serum on the proliferative potential and migration rate of mesenchymal stromal cells in vitro, as well as on the healing of modeled bone defects in rats. This bioregulatory preparation stimulated proliferation of mesenchymal stromal cells from deciduous tooth pulp in vitro, but did not affect the rate of their migration in two-dimensional cultures. In vivo experiments showed that application of this preparation in combination with hydroxyapatite and chitosan gel accelerated bone tissue regeneration, thus ensuring restoration of morphologically normal bone matrix.

Induction of Osteogenesis in Rat Bone Tissue Using Cryogenically Structured Porous 3D Materials Containing a Bioregulator.

We studied osteogenesis induction after implantation of porous cryogenically structured 3D scaffolds based on chitosan, alginate, and serum albumin and containing a bioregulator from bovine serum into in vivo modeled experimental bone defect in rats. It was shown that such 3D-matrices are effective as osteoconductors due to their effect on osteoblast precursors. All types of bioregulator-loaded 3D materials promote active bone repair, which manifested in restoration of the dense bone tissue, formation of the bone marrow, and the recovery of osteons on day 14 after surgery.

Extraction of residual heavy metals from commercial chitosan and approach to preparation of oligochitosan hydrochloride.

For biomedical applications, chitosan and oligochitosan must be appropriately characterized and meet pharmacological requirements in terms of contamination by residual heavy metals. In this work, a series of commercial chitosans was analyzed by ICP-MS method, and high concentration of Fe (44-382 ppm), Cr (3.1-35.

Consequences of chitosan decomposition by nitrous acid: Approach to non-branched oligochitosan oxime.

It is well known that chitosan degradation by nitrous acid leads to oligochitosan (oligoCHI-ahm) bearing reactive 2,5-anhydromannose (3,4-dihydroxy-5-hydroxymethyl-tetrahydrofuran-2-aldehyde) units at the new reducing ends of macromolecules. Standard protocol requires reduction of oligoCHI-ahm with NaBH to corresponding oligoCHI-hml bearing unreactive hydroxymethyl group instead of reactive aldehyde group. For the first time, HP SEC as well as UV and CD spectroscopy methods have revealed that the reduction leads to an indefinite side modification and the formation of a branched oligoCHI-hml with increased molecular weight.