| 1. |
- Cheng, Kaiyuan, et al.
(författare)
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Injectable tricalcium phosphate/calcium sulfate granule enhances bone repair by reversible setting reaction
- 2021
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Ingår i: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier. - 0006-291X .- 1090-2104. ; 557, s. 151-158
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Tidskriftsartikel (refereegranskat)abstract
- Towards repairing bone defects, calcium sulfate and calcium phosphate cement have been recognized as promising bone grafts. However, the current bone cements are generally lack of proper porosity for cell migration and new tissue formation. On the other hand, porous scaffold cannot be delivered by injection, which limits its use its clinical use. Herein, we develop a novel tricalcium phosphate/calcium sulfate granule to overcome the limitations of injectable cements and traditional scaffolds. The biocompatible granule underwent in situ self-setting to form scaffold with porous structure after injection. It con-tributes to calcium deposition and upregulation of osteogenic genes of mesenchymal stem cells in a time-dependent manner. Within three months, cavitary bone defects of distal rabbit femurs implanted the granules exhibited better bone formation than those with those implanted with autologous bone.
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| 2. |
- Fu, Le, et al.
(författare)
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Biodegradable Si3N4 bioceramic sintered with Sr, Mg and Si for spinal fusion : Surface characterization and biological evaluation
- 2018
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Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 12, s. 260-275
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Tidskriftsartikel (refereegranskat)abstract
- Silicon nitride (Si3N4) is an industrial ceramic used in spinal fusion and maxillofacial reconstructionbecause of its excellent mechanical properties and good biocompatibility. This study compares the sur-face properties, apatite formation ability, bacterial infection, cell-biomaterial interactions, and in vivotoxicity (zebrafish) of newly developed Si3N4 bioceramics (sintered with bioactive sintering additivesSrO, MgO and SiO2) with two standard biomaterials; titanium (Ti) and traditional Si3N4 bioceramics (sin-tered with standard sintering additives Al2O3 and Y2O3). In general, Si3N4 bioceramics (both the newlydeveloped and the traditional) displayed less in vitro bacterial affinity than Ti, which may arise fromdifferences in the surface properties between these two types of material. The newly developed Si3N4bioceramics developed lower biofilm coverage and thinner biofilm, compared to traditional Si3N4 bioce-ramics. The effects of ionic dissolution products (leach) on proliferation and differentiation of MC3T3-E1cell were also investigated. Ionic dissolution products containing moderate amount of Sr, Mg and Siions (approximately 4.72 mg/L, 3.26 mg/L and 3.67 mg/L, respectively) stimulated osteoblast prolifera-tion during the first 2 days in culture. Interestingly, ionic dissolution products from the traditional Si3N4bioceramics that contained small amount of Si and Y ions achieved the greatest stimulatory effect foralkaline phosphatase activity after 7 days culture. The toxicity of ionic dissolution products was investi-gated in a putative developmental biology model: zebrafish (Danio rerio). No toxicity, or developmentalabnormalities, was observed in zebrafish embryos exposed to ionic dissolution products, for up to 144 hpost fertilization. These newly developed Si3N4 bioceramics with bioactive sintering additives show greatpotential as orthopedic implants, for applications such as spinal fusion cages. Future work will focus onevaluation of the newly developed Si3N4 bioceramics using a large animal model.
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| 3. |
- Mi, Yushuai, et al.
(författare)
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miR-181a-5p promotes the progression of gastric cancer via RASSF6-mediated MAPK signalling activation
- 2017
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Ingår i: Cancer Letters. - : ELSEVIER IRELAND LTD. - 0304-3835 .- 1872-7980. ; 389, s. 11-22
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Tidskriftsartikel (refereegranskat)abstract
- We previously discovered that Ras association domain family member 6 (RASSF6) was downregulated and predicted poor prognosis in GC patients. However, the mechanisms of the down regulation of RASSF6 in GC remained unclear. Increasing evidence indicates that dysregulation of microRNAs promotes the progression of cancer through the repression of tumour suppressors. Here, we identified miR-181a-5p as a novel regulator of RASSF6 in GC. Functionally, ectopic expression or silencing of miR-181a-5p, respectively, promoted or inhibited GC cell proliferation, colony formation and cell cycle transition, as well as enhanced or prevented the invasion, metastasis of GC cells and epithelial to mesenchymal transition of GC cells in vitro and in vivo. Molecularly, miR-181a-5p functioned as an onco-miRNA by activating the RASSF6-regulated MAKP pathway. Overexpression or silencing of RASSF6 could partially reverse the effects of the overexpression or repression of miR-181a-5p on GC progress caused by activation of the MAKP pathway in vitro and in vivo. Clinically, high miR-181a-5p expression predicted poor survival in GC patients, especially combined with low RASSF6 expression. Collectively, we identified miR-181a-5p as an onco-miRNA, which acts by directly repressing RASSF6 in GC. (C) 2017 The Authors. Published by Elsevier Ireland Ltd.
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| 4. |
- Shi, Liyang, et al.
(författare)
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Self-Healing Silk Fibroin-Based Hydrogel for Bone Regeneration: Dynamic Metal-Ligand Self-Assembly Approach
- 2017
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X.
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Tidskriftsartikel (refereegranskat)abstract
- Despite advances in the development of silk fibroin (SF)-based hydrogels, current methods for SF gelation show significant limitations such as lack of reversible crosslinking, use of nonphysiological conditions, and difficulties in controlling gelation time. In the present study, a strategy based on dynamic metal-ligand coordination chemistry is developed to assemble SF-based hydrogel under physiological conditions between SF microfibers (mSF) and a polysaccharide binder. The presented SF-based hydrogel exhibits shear-thinning and autonomous self-healing properties, thereby enabling the filling of irregularly shaped tissue defects without gel fragmentation. A biomineralization approach is used to generate calcium phosphate-coated mSF, which is chelated by bisphosphonate ligands of the binder to form reversible crosslinkages. Robust dually crosslinked (DC) hydrogel is obtained through photopolymerization of acrylamide groups of the binder. DC SF-based hydrogel supports stem cell proliferation in vitro and accelerates bone regeneration in cranial critical size defects without any additional morphogenes delivered. The developed self-healing and photopolymerizable SF-based hydrogel possesses significant potential for bone regeneration application with the advantages of injectability and fit-to-shape molding.
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| 5. |
- Wei, Zhu, et al.
(författare)
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Injectable and assembled 3D solid structure for free-to-fixed shape in bone reconstruction
- 2020
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Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 21
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Tidskriftsartikel (refereegranskat)abstract
- There is a gap between injectable and scaffold-like bioceramics. Injectable bioactive materials, such as bone cement and hydrogel, are good for minimized surgery, but the extremely low porosity and small pore size limited enhanced bone repair and regeneration. Macroporous bioceramic scaffolds are used because of the controlled pore size and porosity, but not injectable. It's a challenge of preparation of an injectable macroporous ceramic scaffold for minimized bone reconstruction. By using the reversible setting reaction of calcium sulfate and combining a dual setting system with magnesium silicate hydrate, the injectable and assembled 3D porous bioceramic scaffold has been successfully developed. The content of amorphous magnesium silicate hydrate in the dual setting system affected the mechanical strength and degradation. The porous structure could be controlled by the size of granules. The granules can also be used for the fabrication of porous materials with varied shapes and customized structures by using a simple injection process. The biological testing showed good biocompatibility and in vitro osteogenesis. By using the femoral lateral condyle defect model, we can see the granules could be injected into the defect and formed a rigid porous structure in situ, and further presented better new bone formation compared with autologous bone chips. Briefly, we demonstrated the first injectable 3D solid porous ceramic structure for minimized bone repair and free-form shaping.
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| 6. |
- Zhu, Wei, et al.
(författare)
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Cemented injectable multi-phased porous bone grafts for the treatment of femoral head necrosis
- 2019
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Ingår i: Journal of materials chemistry. B. - : ROYAL SOC CHEMISTRY. - 2050-750X .- 2050-7518. ; 7:18, s. 2997-3006
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Tidskriftsartikel (refereegranskat)abstract
- Femoral head necrosis (FHN) can induce musculoskeletal disability. It presents a challenge from diagnostic and therapeutic points of view. Open surgery for the treatment of FHN is not an optimal route. To minimize the surgery window, an injectable material with a porous structure and bioactive nature is preferred. The fabrication of an injectable porous bone graft via a simple route was the aim of our study. Therefore, cemented multi-phased calcium phosphate porous granules have been studied with varied phase compositions, pore sizes and porosities, and degradation rates. Granules templated by PEG 100-600 mu m were chosen for cell toxicity and in vitro osteogenic potential testing. Rabbits, making up a femoral head necrosis model, were implanted with granule A. Mature cancellous bone tissue was observed in the femoral head defect after 2 months implantation. The results indicate that the newly formed injectable bioactive porous grafts could be a good candidate for the treatment of femoral head necrosis.
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