ABSTRACT
<p><b>OBJECTIVE</b>To fabricate organic-inorganic composite tissue engineering scaffolds for reconstructing calcified cartilage layer based on three-dimensional (3D) printing technique.</p><p><b>METHODS</b>The scaffolds were developed by 3D-printing technique with highly bioactive calcium-magnesium silicate ultrafine particles of 1%, 3% and 5% of mass fraction, in which the organic phases were composed of type I collagen and sodium hyaluronate. The 3D-printed scaffolds were then crosslinked and solidified by alginate and CaCl₂ aerosol. The pore size and distribution of inorganic phase were observed with scanning electron microscope (SEM); the mechanical properties were tested with universal material testing machine, and the porosity of scaffolds was also measured.</p><p><b>RESULTS</b>Pore size was approximately (212.3 ± 34.2) μm with a porosity of (48.3 ± 5.9)%, the compressive modulus of the scaffolds was (7.2 ± 1.2) MPa, which was irrelevant to the percentage changes of calcium-magnesium silicate, the compressive modulus was between that of cartilage and subchondral bone.</p><p><b>CONCLUSION</b>The porous scaffolds for calcified cartilage layer have been successfully fabricated, which would be used for multi-layered composite scaffolds in osteochondral injury.</p>
Subject(s)
Bioprinting , Cartilage , Materials Testing , Porosity , Printing, Three-Dimensional , Tissue Engineering , Methods , Tissue Scaffolds , ChemistryABSTRACT
A new method to revel RFLPs is presented. The human genomic DNAwas purified by saturatedNaCl solution and the pAW101 probe labelled with digoxigenin-dUTP. The relationships of RFLPsand genetic patterns of PGM1 (phosphoglucomutase),EsD (esterase D),GLO1 (glyoxalase)and ACP(acid phosphatase ) between the fillal generation and parental generation were detected in 15 families(among them 11 cases were aborted fetuses). The probability of paternity (w)was caculated accor-ding to Essen - Moller's formula, each w vlua was over 99. 73 %, reached the standard of incladingpaternity. An effective,rapid, and non-toxic RFLPs technique was established, which is easy to man-age in common lab oratories.