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Article Citation - WoS: 36Citation - Scopus: 43The Effect of Boron-Containing Nano-Hydroxyapatite on Bone Cells(Humana Press inc, 2020) Gizer, Merve; Kose, Sevil; Karaosmanoglu, Beren; Taskiran, Ekim Z.; Berkkan, Aysel; Timucin, Muharrem; Korkusuz, PetekMetabolic diseases or injuries damage bone structure and self-renewal capacity. Trace elements and hydroxyapatite crystals are important in the development of biomaterials to support the renewal of bone extracellular matrix. In this study, it was assumed that the boron-loaded nanometer-sized hydroxyapatite composite supports the construction of extracellular matrix by controlled boron release in order to prevent its toxic effect. In this context, boron release from nanometer-sized hydroxyapatite was calculated by ICP-MS as in large proportion within 1 h and continuing release was provided at a constant low dose. The effect of the boron-containing nanometer-sized hydroxyapatite composite on the proliferation of SaOS-2 osteoblasts and human bone marrow-derived mesenchymal stem cells was evaluated by WST-1 and compared with the effects of nano-hydroxyapatite and boric acid. Boron increased proliferation of mesenchymal stem cells at high doses and exhibited different effects on osteoblastic cell proliferation. Boron-containing nano-hydroxyapatite composites increased osteogenic differentiation of mesenchymal stem cells by increasing alkaline phosphatase activity, when compared to nano-hydroxyapatite composite and boric acid. The molecular mechanism of effective dose of boron-containing hydroxyapatite has been assessed by transcriptomic analysis and shown to affect genes involved in Wnt, TGF-beta, and response to stress signaling pathways when compared to nano-hydroxyapatite composite and boric acid. Finally, a safe osteoconductive dose range of boron-containing nano-hydroxyapatite composites for local repair of bone injuries and the molecular effect profile in the effective dose should be determined by further studies to validation of the regenerative therapeutic effect window.Article Citation - WoS: 4Evaluation of Boron Ore in Cement Production(Taylor & Francis inc, 2012) Yesilmen, Seda; Gurbuz, AyhanA new genre of high belite cement named boron-modified active belite (BAB) cement that was developed using byproduct of boric acid production was investigated. The cement proved superior in compressive strength and permeability characteristics in the previous studies. Long term storage of cement is known to alter the mechanical properties of concrete made with the aged cement. The article investigated the BAB cement in aged condition-stored in silos for about three years-variations of mechanical and physical properties of specimens during a one-year period. An additional comparison is also performed with specimens cast using fresh Ordinary Portland Cement (OPC) of the same grade in order to present the development of mechanical and physical properties in a qualitative manner. Lower 28 day compressive strength values are observed for BAB cement compared to OPC specimens; however, higher rate of strength development of BAB cement resulting from high belite content led to comparable long term strength values with OPC specimens.
