ABSTRACT
<p><b>BACKGROUND</b>Three-dimensional (3D) printing technology holds great promise for treating diseases or injuries that affect human bones with enhanced performance over traditional techniques. Different patterns of design can lead to various mechanical properties and biocompatibility to various degrees. However, there is still a long way to go before we can fully take advantage of 3D printing technologies.</p><p><b>METHODS</b>This study tailored 3D printed scaffolds with gelatin and platelets to maximize bone regeneration. The scaffolds were designed with special internal porous structures that can allow bone tissue and large molecules to infiltrate better into the scaffolds. They were then treated with gelatin and platelets via thermo-crosslinking and freeze-drying, respectively. Vascular endothelial growth factor (VEGF) and transforming growth factor (TGF)-β1 were measured at different time points after the scaffolds had been made. Cell proliferation and cytotoxicity were determined via cell counting kit-8 (CCK-8) assay.</p><p><b>RESULTS</b>There was a massive boost in the level of VEGF and TGF-β1 released by the scaffolds with gelatin and platelets compared to that of scaffolds with only gelatin. After 21 days of culture, the CCK-8 cell counts of the control group and treated group were significantly higher than that of the blank group (P < 0.05). The cytotoxicity test also indicated the safety of the scaffolds.</p><p><b>CONCLUSIONS</b>Our experiments confirmed that the 3D printed scaffolds we had designed could provide a sustained-release effect for growth factors and improve the proliferation of preosteoblasts with little cytotoxicity in vitro. They may hold promise as bone graft substitute materials in the future.</p>
Subject(s)
Animals , Mice , 3T3 Cells , Biocompatible Materials , Chemistry , Cell Proliferation , Cell Survival , Gelatin , Chemistry , Printing, Three-Dimensional , Tissue Engineering , Methods , Tissue Scaffolds , Chemistry , Transforming Growth Factor beta1 , Chemistry , Pharmacology , Vascular Endothelial Growth Factor A , Chemistry , PharmacologyABSTRACT
<p><b>OBJECTIVE</b>The present study aimed to review the characteristics and influencing factors of squeaking after ceramic-on-ceramic (CoC) total hip arthroplasty (THA) and to analyze the possible mechanisms of the audible noise.</p><p><b>DATA SOURCES</b>The data analyzed in this review were based on articles from PubMed and Web of Science.</p><p><b>STUDY SELECTION</b>The articles selected for review were original articles and reviews found based on the following search terms: "total hip arthroplasty", "ceramic-on-ceramic", "hip squeaking", and "hip noise."</p><p><b>RESULTS</b>The mechanism of the squeaking remains unknown. The possible explanations included stripe wear, edge loading, a third body, fracture of the ceramic liner, and resonance of the prosthesis components. Squeaking occurrence is influenced by patient, surgical, and implant factors.</p><p><b>CONCLUSIONS</b>Most studies indicated that squeaking after CoC THA was the consequence of increasing wear or impingement, caused by prosthesis design, patient characteristics, or surgical factors. However, as conflicts exist among different articles, the major reasons for the squeaking remain to be identified.</p>
Subject(s)
Humans , Arthroplasty, Replacement, Hip , Ceramics , Therapeutic Uses , Hip Prosthesis , Noise , Osteoarthritis, Hip , General SurgeryABSTRACT
<p><b>OBJECTIVE</b>In order to study the effect of the polymorphism at the exon2 region of the (3-LG allele gene on milk composition and yield.</p><p><b>METHODS</b>The single-strand conformation polymorphism method (PCR-SSCP) was used to analyze for polymorphism the exon2 region of the 3-LG gene (NCBI accession number: DQ489319) in Chinese Holstein.</p><p><b>RESULTS</b>Eight SSCP patterns were detected in the fragments: ab, abc, abd, abe, abcd, abce, abde and abcde, and the patterns frequencies as follows: 0.14, 0.10, 0.27, 0.23, 0.05, 0.04, 0.11 and 0.06 (P < 0.05); Six single nucleotide polymorphism (SNP) were detected in this study: sitel C>T, site2 T>C, site3 C>T, site4 C>C, site5 C> A, site6 A>T or C, and the polymorphism infonnation content (PIC) of these SNPs were in median or high polymorphism (PIC > 0.25).</p><p><b>CONCLUSION</b>These SNPs at the exon2 region of the beta-LG gene were remarkably and affected milk performance traits (milk yield, protein and fat contents) in Chinese Holstein.</p>