China
Africa
Explore chapters and articles related to this topic
Effect of Scaffolds with Bone Growth Factors on New Bone Formation
Published in Gilson Khang, Handbook of Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine, 2017
Hae-Ryong Song, Swee-Hin Teoh, Hak-Jun Kim, Ji-Hoon Bae, Sung Eun Kim, Young-Pil Yun, Muhammad Qasim, Jerry Chan, Zhi-Yong Zhang, Chang-Wug Oh, Jun-Ho Wang
OCN is secreted solely by the osteoblasts, and is thought to play a role in the body’s metabolic regulation and is proosteoblastic, or bone building. It is also implicated in the bone mineralization and calcium ion homeostasis. Osteopontin has been implicated as an important factor in bone remodeling. As shown in Fig. 38.43A, the OCN expression was higher with 2.3-fold on 21 days in BMP-2 (100 ng)/Hep-chitosan scaffolds versus chitosan scaffolds. There are significant difference in the OCN expression between chitosan scaffolds and BMP-2 (50 ng)/Hep-chitosan scaffolds at 21 days (*P < 0.05). In addition, there are significant differences in the OCN expression of BMP-2 (100 ng)/Hep-chitosan scaffolds versus BMP-2 (50 ng)/Hep-chitosan scaffolds at 21 days (**P < 0.001). Also, the osteopontin expression was higher with 2.9-fold on 21 days in BMP-2 (100 ng)/Hep-chitosan scaffolds versus chitosan scaffolds (Fig. 38.43B; **P < 0.001). There are significant difference in the osteopontin expression between chitosan scaffolds and BMP-2 (50 ng)/Hep-chitosan scaffolds at 21 days (*P < 0.05). Moreover, there are significant differences in the osteopontin expression of BMP-2 (100 ng)/Hep-chitosan scaffolds versus BMP-2 (50 ng)/Hep-chitosan scaffolds at 21 days (**P < 0.001).
Potential Targets for Imaging Atherosclerosis
Published in Robert J. Gropler, David K. Glover, Albert J. Sinusas, Heinrich Taegtmeyer, Cardiovascular Molecular Imaging, 2007
David N. Smith, Mehran M. Sadeghi, Jeffrey R. Bender
Over time, the advanced lesion begins to calcify (38). While multiple theories exist, it is speculated that vesicles from dead macrophage/foam cells and VSMC may contain proteins that bind calcium within the plaque (38). Osteopontin, a noncollagenous glycoprotein secreted by macrophages and VSMCs, is upregulated and binds hydroxyapetite and calcium specifically in coronary artery disease (CAD) (39). Osteopontin gene expression levels correlate with severity of arterial calcification (40). Calcification increases with age (41,42). As correlated with autopsy studies, the more significant the coronary calcification, the more severe the vessel stenosis (43). Calcification occurs early in obstructive disease and significantly increases the strength of the plaque (44). While over time, this reduces the likelihood of plaque rupture, earlier in disease, there is increased vulnerability at junctions of calcification and noncalcified vessels. These sites predispose to acute plaque rupture and acute coronary events (45). Calcification can involve the vessel elastic membrane without structural alteration or can be associated with remodeling (46). Calcium is consistently found in areas of significant vessel stenosis (47). Plaque calcification occurs significantly before the onset of clinical symptoms and has been touted as an indication for early intervention (48).
Nanocomposite Hydrogels for Biomedical Applications
Published in Jince Thomas, Sabu Thomas, Nandakumar Kalarikkal, Jiya Jose, Nanoparticles in Polymer Systems for Biomedical Applications, 2019
M. Karthika, Aswathy Vasudevan, Jiya Jose, Nandakumar Kalarikkal, Sabu Thomas
Researchers are developing future generation of advanced biomaterials by combining inorganic ceramic nanoparticles with natural or synthetic polymers. Similarly, the employment of inorganic nanomaterials for improving the hydrogel properties is additionally being reported.22 Most of the inorganic nanomaterials are already present in our body and are necessary for the normal functioning, and there will not be any adverse impact. Some of them, like calcium and silicon, facilitate with preventing bone loss and skeletal development. Others, like nanoclays, improve the structural formation. A variety of bioactive nanoparticles, like hydroxyapatite (nHA), synthetic silicate nanoparticles, bioactive glasses, silica, calcium phosphate, glass ceramic, β-wollastonite, etc., are reported for biomedical applications. From these materials, advanced biomaterials can be created by combining inorganic ceramic nanoparticles with natural or synthetic polymers. The inorganic nanoparticles contain minerals that are already present within the body that is critical for the normal functioning of human tissues. It also shows desirable biological responses, for instance, calcium, which is present in bone and plays an important role in bone development and maintenance. The presence of intracellular calcium and phosphate within the osteoblasts promote the deposition of the mineralized matrix and stop bone loss. Similarly, silicon, another component present in ceramic nanoparticles, will play a key role in skeletal development. Considering these facts, incorporating such inorganic nanoparticles in polymeric hydrogels is predicted to supply bioactive characteristics to the network. Different sorts of NCHs are synthesized by incorporating ceramic nanoparticles inside the polymer matrix. For instance, nHA was incorporated within poly(ethylene glycol) (PEG) matrix to get extremely elastomeric NCHs. It enhances the mechanical strength and improves the physiological stability of the nanocomposite. Another vital material is nanoclay (synthetic salt nanoplatelets). It will induce osteogenic differentiation of human mesenchymal stem cells without the utilization of exogenous growth factors. It will trigger a series of events that follow the temporal pattern of osteogenic differentiation, bone-related matrix protein deposition (osteocalcin and osteopontin), followed by matrix mineralization. The distinctive bioactive properties of the nanoclay may be wont to create devices like injectable tissue repair matrices, bioactive fillers, or therapeutic agents helpful for triggering specific cellular responses toward bone-related tissue engineering approaches. The synthetic silicate nanoplatelets produce mechanically robust and tissue-adhesive NCHs once they are mixed with linear and branched polymers. The physical and chemical properties of silicate-based nanocomposites result in the high surface interactions and also the noncovalent interactions because the polymer chains will reversibly sorb and desorb on the silicate surfaces. The addition of silicates will improve the elongation of the polymeric hydrogels attributable to the formation of physically cross-linked networks. This modified PEG network enhances the cell and tissue adhesive properties of the NCHs.
Numerical investigation of the role of osteopontin on the mechanical strength of biological composites
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
The basic building blocks in bone include hydroxyapatite minerals, collagen proteins and non-collagenous proteins such as osteopontin (Wegst and Ashby 2004; Dunlop and Fratzl 2010; Ji and Gao 2010; Launey et al. 2010; Wang and Gupta 2011). The focus of this paper is osteopontin. Osteopontin is an essential component in bone, and osteopontin-deficient bone was found to have lower fracture toughness (Thurner et al. 2010). Besides, osteopontin was also found to be crucial for the regulation of mineralisation (Hunter 2013; Holm et al. 2014; Foster et al. 2018) and high energy dissipation (Fantner et al. 2005; Fantner et al. 2007; Zappone et al. 2008). Previous studies also suggested that osteopontin acts as natural adhesive in biological materials (McKee and Nanci 1995, 1996a, 1996b; Nanci 1999; Fantner et al. 2005).
Effects of latex membrane on guided regeneration of long bones
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Bruna Leonel Carlos, Jéssica Suzuki Yamanaka, Gabriela Rezende Yanagihara, Ana Paula Macedo, Plauto Christopher Aranha Watanabe, João Paulo Mardegan Issa, Rondinelli Donizetti Herculano, Antônio Carlos Shimano
Bone repair involves a series of biological events often mediated by the action of proteins. To better understand the influence of latex membrane use on bone regeneration, osteogenic proteins were quantified. After one and 4 weeks post-surgery, the L group had a significantly higher expression of osteopontin than the C group and the increase was associated with new bone formation in treated groups. Osteopontin is responsible for mineralization and adhesion of osteoblasts and osteoclasts on the surface of the bone matrix. In addition to changes in angiogenic factors reported by previous research, our findings suggest that latex can stimulate the action of osteogenic cells.
Carbon-based nanomaterials as scaffolds in bone regeneration
Published in Particulate Science and Technology, 2020
Liana Crisan, Bogdan Vasile Crisan, Simion Bran, Florin Onisor, Gabriel Armencea, Sergiu Vacaras, Ondine Patricia Lucaciu, Ileana Mitre, Mihaela Baciut, Grigore Baciut, Cristian Dinu
Osteopontin (OP), a non-collagenic phosphoprotein contains in its structure GDR tripeptide, characteristic of adhesion molecules, tripeptide which can be found in the structure of fibronectin and fibrinogen, vitronectin, osteonectin, suggesting the involvement of osteopontin in cell–cell adhesion phenomenon–cell, cell–extracellular matrix respectively taking place during cell proliferation and migration (Yamate et al. 1997).