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61.
van de Watering FC van den Beucken JJ Walboomers XF Jansen JA 《Clinical oral implants research》2012,23(2):151-159
Objectives: The present study aimed to provide temporal information on material degradation and bone formation using composite (C) bone defect filler materials consisting of calcium phosphate cement (CaP) and poly(d ,l ‐lactic‐co‐glycolic acid) (PLGA) microparticles (20 or 30 wt%) in rat critical‐sized cranial defects. Materials and methods: Critical‐sized bicortical cranial defects were created in 48 rats and CaP/PLGA cement composites were implanted for 4, 8 and 12 weeks (n=8). Results: Histological analysis of the retrieved specimens revealed that implant degradation was significantly faster for C30% (remaining implant up to 89.4 ± 4.4% at 12 weeks) compared with C20% (remaining implant upto 94.8 ± 2.1% at 12 weeks), albeit that overall degradation was limited. Although bone formation was limited in both experimental groups (upto 685765.9 μm2 for C20% vs. 917603.3 μm2 for C30%), C30% showed a significant temporal increase of total bone formation. The percentage of defect bridging was comparable for C20% and C30% at all implantation periods (range 40 ± 25.5% at week 4 to 65 ± 20% at week 12 for C20%; range 51.8 ± 7.8% at week 4 to 70.5 ± 16.2% at week 12 for C30%). Conclusion: The amount of PLGA‐microparticles in the CaP/PLGA cement composites demonstrated acceleration of material degradation, while bone formation was found not to be influenced. Further optimization of the composite material is necessary to increase control over degradation and tissue ingrowth. To cite this article :van de Watering FCJ, van den Beucken JJJP, Walboomers XF, Jansen JA. Calcium phosphate/poly(d ,l ‐lactic‐co‐glycolic acid) composite bone substitute materials: evaluation of temporal degradation and bone ingrowth in a rat critical‐sized cranial defect.Clin. Oral Impl. Res. 23 , 2012; 151–159. doi: 10.1111/j.1600‐0501.2011.02218.x 相似文献
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Vincent JJ Odekerken Teus van Laar Michiel J Staal Arne Mosch Carel FE Hoffmann Peter CG Nijssen Guus N Beute Jeroen PP van Vugt Mathieu WPM Lenders M Fiorella Contarino Marieke SJ Mink Lo J Bour Pepijn van den Munckhof Ben A Schmand Rob J de Haan P Richard Schuurman Rob MA de Bie 《Lancet neurology》2013,12(1):37-44
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Nerea Rodriguez Rodriguez Lieven Machiels Bieke Onghena Jeroen Spooren Koen Binnemans 《RSC advances》2020,10(12):7328
Several deep-eutectic solvents (DESs) were tested for the valorisation of goethite residue produced by the zinc industry. The objective of the work was to selectively recover zinc from the iron-rich matrix using deep-eutectic solvents as lixiviants. The effect of the type of hydrogen bond donor and hydrogen bond acceptor of the deep-eutectic solvent on the leaching efficiency was studied. Levulinic acid–choline chloride (xChCl = 0.33) (LevA–ChCl) could selectively leach zinc from the iron-rich matrix, and it was selected as the best-performing system to be used in further study. The leaching process was optimised in terms of temperature, contact time, liquid-to-solid ratio and water content of the deep-eutectic solvent. The role of the choline cation on the leaching process was investigated by considering the leaching properties of a LevA–CaCl2 mixture. The goethite residue was also leached with pure levulinic acid. The results were compared to a purely hydrometallurgical approach using sulphuric acid leaching. Leaching with LevA–ChCl resulted in higher selectivity compared to the conventional “hot leaching” with 80 g L−1 sulphuric acid. Furthermore, a slightly higher zinc recovery and comparable selectivity for zinc over iron were achieved with LevA–ChCl compared to conventional “neutral leaching” with 10 g L−1 sulphuric acid.A mixture of levulinic acid and choline chloride can be used to selectively leach zinc from industrial residues with iron-rich matrices. 相似文献
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Vince B. C. Biemans Jasmijn A. M. Sleutjes Annemarie C. de Vries Alexander G. L. Bodelier Gerard Dijkstra Bas Oldenburg Mark Löwenberg Adriaan A. van Bodegraven Andrea E. van der Meulen-de Jong Nanne K. H. de Boer Nidhi Srivastava Rachel L. West Tessa E. H. Römkens Carmen S. Horjus Talabur Horje Jeroen M. Jansen C. Janneke van der Woude Jildou Hoekstra Rinse K. Weersma Fiona D. M. van Schaik Frank Hoentjen Marieke J. Pierik the Dutch Initiative on Crohn Colitis 《Alimentary pharmacology & therapeutics》2020,51(9):880-888