Baler, R. V., Wijnhoven, I. B., del Valle, V. I., Giovanetti, C. M., & Vivanco, J. F. (2019). Microporosity Clustering Assessment in Calcium Phosphate Bioceramic Particles. Front. Bioeng. Biotechnol., 7(281), 7 pp.
Abstract: There has been an increase in the application of different biomaterials to repair hard tissues. Within these biomaterials, calcium phosphate (CaP) bioceramics are suitable candidates, since they can be biocompatible, biodegradable, osteoinductive, and osteoconductive. Moreover, during sintering, bioceramic materials are prone to form micropores and undergo changes in their surface topographical features, which influence cellular physiology and bone ingrowth. In this study, five geometrical properties from the surface of CaP bioceramic particles and their micropores were analyzed by data mining techniques, driven by the research question: what are the geometrical properties of individual micropores in a CaP bioceramic, and how do they relate to each other? The analysis not only shows that it is feasible to determine the existence of micropore clusters, but also to quantify their geometrical properties. As a result, these CaP bioceramic particles present three groups of micropore clusters distinctive by their geometrical properties. Consequently, this new methodological clustering assessment can be applied to advance the knowledge about CaP bioceramics and their role in bone tissue engineering.
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del Rio, A. V., Buys, B., Campos, J. L., Mendez, R., & Mosquera-Corral, A. (2015). Optimizing upflow velocity and calcium precipitation in denitrifying granular systems. Process Biochem., 50(10), 1656–1661.
Abstract: The denitrification process was studied in two granular biomass denitrifying reactors (USB1 and USB2). In USB1 large quantities of biomass were accumulated (9.5 gVSS L-1) allowing for the treatment of high nitrogen loads (3.5 g NO3--N L-1 d(-1)). As the biomass granulation process is not immediate the effects of different upflow velocities (0.12-5.5 m h(-1)) and calcium contents (5-200 mg Ca2+ L-1) were studied in order to speed up the process. Obtained results indicate that the optimum values for these parameters, which allow for the stable operation of USB1, are of 0.19 m h(-1) and 60 mg Ca2+ L-1. Then these optimum conditions were applied to USB2 where the effects of concentrations from 335 to 1000 mg NO3--N L-1 were tested. In these conditions nitrate concentrations of 1000 mg NO3--N L-1 are required for denitrifying granular biomass formation. Summarizing denitrifying granules can be formed at low upflow velocities and in hard or extremely hard water composition conditions if sufficient high nitrogen loads are treated. (C) 2015 Elsevier Ltd. All rights reserved.
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Millan, C., Vivanco, J. F., Benjumeda-Wijnhoven, I. M., Bjelica, S., & Santibanez, J. F. (2018). Mesenchymal Stem Cells and Calcium Phosphate Bioceramics: Implications in Periodontal Bone Regeneration. Adv.Exp.Med.Biol., 1107, 91–112.
Abstract: In orthopedic medicine, a feasible reconstruction of bone structures remains one of the main challenges both for healthcare and for improvement of patients' quality of life. There is a growing interest in mesenchymal stem cells (MSCs) medical application, due to their multilineage differentiation potential, and tissue engineering integration to improve bone repair and regeneration. In this review we will describe the main characteristics of MSCs, such as osteogenesis, immunomodulation and antibacterial properties, key parameters to consider during bone repair strategies. Moreover, we describe the properties of calciumphosphate (CaP) bioceramics, which demonstrate to be useful tools in combination with MSCs, due to their biocompatibility, osseointegration and osteoconduction for bone repair and regeneration. Also, we overview the main characteristics of dental cavity MSCs, which are promising candidates, in combination with CaP bioceramics, for bone regeneration and tissue engineering. The understanding of MSCs biology and their interaction with CaP bioceramics and other biomaterials is critical for orthopedic surgical bone replacement, reconstruction and regeneration, which is an integrative and dynamic medical, scientific and bioengineering field of research and biotechnology.
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Ramajo, L., Rodriguez-Navarro, A. B., Duarte, C. M., Lardies, M. A., & Lagos, N. A. (2015). Shifts in shell mineralogy and metabolism of Concholepas concholepas juveniles along the Chilean coast. Mar. Freshw. Res., 66(12), 1147–1157.
Abstract: Along the west coast of South America, from the tropical zone to the Patagonian waters, there is a significant latitudinal gradient in seawater temperature, salinity and carbonate chemistry. These physical-chemical changes in seawater induce morphological and physiological responses in calcifying organisms, which may alter their energy budget and calcification processes. In this study, we study the organism energy maintenance (i.e. metabolic rate) and mineralogical composition of the shell of the juvenile marine snails Concholepas concholepas (Gastropoda: Muricidae), collected from benthic populations located similar to 2000km apart, varies across geographic regions along the Chilean coast. We found that in juvenile snails, the calcite:aragonite ratio in the pallial shell margin (i.e. newly deposited shell) increase significantly from northern to southern populations and this increase in calcite precipitation in the shell of juveniles snails was associated with a decrease in oxygen consumption rates in these populations. Our result suggests that calcite secretion may be favoured when metabolic rates are lowered, as this carbonate mineral phase might be less energetically costly for the organism to precipitate. This result is discussed in relation to the natural process such as coastal upwelling and freshwater inputs that promote geographic variation in levels of pH and carbonate saturation state in seawater along the Chilean coast.
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