Bone tissue is a hierarchically structured material composed at the nanoscale by an organic matrix of collagen type I, apatite mineral and water. We considered an idealized 3D geometrical model of the mineralized collagen fibril in order to analyze the influence of structural factors, i.e. tortuosity, constrictivity, on the water effective diffusivity. The average values of the factors investigated in the diffusivity are computed on 5000 iterations by means of the Montecarlo method. The input parameters of the numerical model are the geometrical dimensions of the apatite mineral, collagen fibrils and their spatial orientation obtained with random extractions from Gaussian probability distribution functions. We analyzed the diffusion phenomenon for concentration gradients parallel to three orthogonal directions (Length, Width and Thickness) and for different scenarios, namely low, intermediate and high apatite volume fraction. For each degree of volume fraction, in the thickness direction, the tortuosity assumes greater values, up to two orders of magnitude, in comparison with the tortuous factors computed in the other directions, highlighting the anisotropy of the nanostructure. Furthermore, it was found that the tortuosity is the dominant parameter which control the effective transport properties within the mineralized collagen fibrils.
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http://dx.doi.org/10.1038/s41598-019-39297-w | DOI Listing |
Molecules
December 2024
Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan.
Mild hypophosphatasia (HPP) can be difficult to distinguish from other bone disorders in the absence of typical symptoms such as the premature loss of primary teeth. Therefore, this study aimed to analyze the crystallinity of hydroxyapatite (HAp) and the three-dimensional structure of collagen in HPP teeth at the molecular level and to search for new biomarkers of HPP. Raman spectroscopy was used to investigate the molecular structure, composition, and mechanical properties of primary teeth from healthy individuals and patients with HPP.
View Article and Find Full Text PDFMolecules
December 2024
Department of Human Nutrition, Faculty of Food Sciences, University of Warmia and Mazury in Olsztyn, 45f Sloneczna, 10-718 Olsztyn, Poland.
Bovine milk is widely recognized as one of the most valuable sources of nutrients such as proteins, fats, vitamins, and minerals that support the development and health of the body. In recent years, there has been increasing scientific interest in exosomes, the small membrane-bound vesicles found in milk. Through their content (e.
View Article and Find Full Text PDFBiomedicines
November 2024
Pole of Morphology, Institute of Experimental and Clinical Research, UCLouvain, 1200 Brussels, Belgium.
Osteogenesis imperfecta (OI) is a rare genetic disorder affecting mainly type I collagen, which leads to bone fragility and deformities. OI patients also present craniofacial abnormalities such as macrocephaly and malocclusion. Recently, craniofacial dysmorphism was highlighted in the osteogenesis imperfecta mouse (oim), a validated model of the most severe form of OI.
View Article and Find Full Text PDFBackground: Patients with chronic kidney disease (CKD) have serum, bone, and vascular abnormalities presenting as chronic kidney disease-mineral bone disorder (CKD-MBD) syndrome. This study sought to identify the parameters with the greatest relative impact on progression of CKD-MBD abnormalities.
Materials And Methods: This prospective study measured 237 parameters including serum markers, clinical variables, dual-energy X-ray absorptiometry (DXA) measurements, vascular calcifications, and histomorphometric results from bone samples obtained at baseline and after 2 - 3 years.
Background: Injectable biostimulator treatments stimulate endogenous collagen in aging skin, but whether they act through similar pathways is unknown. This study evaluates two biostimulatory agents' effects on genes, expressed proteins, and respective pathways as potential aging biomarkers and treatment outcomes.
Methods: This 13-week, randomized, single-center, comparative study compared volume change and gene expression stimulated by poly-L-lactic acid (PLLA-SCATM) and calcium hydroxylapatite (CaHA-R) via punch biopsy in the nasolabial fold (NLF).
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