Publications

@article{Qiu2023-np,

title = {Elucidating osseointegration in vivo in 3D printed scaffolds 

 eliciting different foreign body responses},

author = {Dewei Qiu and Chuanliang Cao and Aruna Prasopthum and Zhenchang Sun and Shan Zhang and Hanwen Yang and Zhiyong Xu and Jun Tao and Fanrong Ai and Jing Yang},

year  = {2023},

date = {2023-10-01},

journal = {Mater. Today Bio},

volume = {22},

number = {100771},

pages = {100771},

publisher = {Elsevier BV},

abstract = {Osseointegration between biomaterial and bone is critical for 

 the clinical success of many orthopaedic and dental implants. 

 However, the mechanisms of in vivo interfacial bonding formation 

 and the role of immune cells in this process remain unclear. In 

 this study, we investigated the bone-scaffold material 

 interfaces in two different 3D printed porous scaffolds 

 (polymer/hydroxyapatite and sintered hydroxyapatite) that 

 elicited different levels of foreign body response (FBR). The 

 polymer/hydroxyapatite composite scaffolds elicited more 

 intensive FBR, which was evidenced by more FBR components, such 

 as macrophages/foreign body giant cells and fibrous tissue, 

 surrounding the material surface. Sintered hydroxyapatite 

 scaffolds showed less intensive FBR compared to the composite 

 scaffolds. The interfacial bonding appeared to form via new bone 

 first forming within the pores of the scaffolds followed by 

 growing towards strut surfaces. In contrast, it was previously 

 thought that bone regeneration starts at biomaterial surfaces 

 via osteogenic stem/progenitor cells first attaching to them. 

 The material-bone interface of the less immunogenic 

 hydroxyapatite scaffolds was heterogenous across all samples, 

 evidenced by the coexistence of osseointegration and FBR 

 components. The presence of FBR components appeared to inhibit 

 osseointegration. Where FBR components were present there was no 

 osseointegration. Our results offer new insight on the in vivo 

 formation of bone-material interface, which highlights the 

 importance of minimizing FBR to facilitate osseointegration for 

 the development of better orthopaedic and dental biomaterials.},

keywords = {3D printing, biomaterials, bone, Foreign body response, Osseointegration, Tissue engineering},

pubstate = {published},

tppubtype = {article}

}

@article{Islam2020-al,

title = {The effect of MgO/TiO2 on structural and crystallization 

 behavior of near invert phosphate-based glasses},

author = {Md Towhidul Islam and Nusrat Sharmin and Graham A Rance and Jeremy J Titman and Andrew J Parsons and Kazi M Zakir Hossain and Ifty Ahmed},

year  = {2020},

date = {2020-04-01},

journal = {J. Biomed. Mater. Res. B Appl. Biomater.},

volume = {108},

number = {3},

pages = {674\textendash686},

publisher = {Wiley},

abstract = {Varying formulations in the glass system of 40P2 O5 ─(24 - 

 x)MgO─(16 + x)CaO─(20 - y)Na2 O─yTiO2 (where 0 $\leq$ x $\leq$ 22 and y = 0 or 1) were prepared via melt-quenching. The 

 structure of the glasses was confirmed by X-ray diffraction 

 (XRD), Fourier transform infrared (FTIR), micro Raman and 

 solid-state nuclear magnetic resonance (NMR) spectroscopies. The 

 thermal properties and the activation energy of crystallization 

 (Ec ) were measured using thermal analysis and the Kissinger 

 equation, respectively. The glass forming ability of the 

 formulations investigated was seen to decrease with reducing MgO 

 content down to 8 mol% and the glass stability region also 

 decreased from 106 to 90°C with decreasing MgO content. The 

 activation energy of crystallization (Ec ) values also decreased 

 from 248 (for 24 mol% MgO glass) to 229 kJ/mol (for the 8 mol% 

 MgO content) with the replacement of MgO by CaO for glasses with 

 no TiO2 . The formulations containing less than 8 mol% MgO 

 without TiO2 showed a strong tendency toward crystallization. 

 However, the addition of 1 mol% TiO2 in place of Na2 O for 

 these glasses with less than 8 mol% MgO content, inhibited 

 their crystallization tendency. Glasses containing 8 mol% MgO 

 with 1 mol% TiO2 revealed a 12°C higher glass transition 

 temperature, a 14°C increase in glass stability against 

 crystallization and a 38 kJ/mol increase in Ec in comparison to 

 their non TiO2 containing counterpart. NMR spectroscopy revealed 

 that all of the formulations contained almost equal percentages 

 of Q1 and Q2 species. However, FTIR and Raman spectroscopies 

 showed that the local structure of the glasses had been altered 

 with addition of 1 mol% TiO2 , which acted as a network 

 modifier, impeding crystallization by increasing the 

 cross-linking between phosphate chains and consequently leading 

 to increased Ec as well as their glass forming ability.},

keywords = {activation energy, biomaterials, crystallization, phosphate   glass},

pubstate = {published},

tppubtype = {article}

}

@article{Ashworth2020-so,

title = {Peptide gels of fully-defined composition and mechanics for 

 probing cell-cell and cell-matrix interactions in vitro},

author = {J C Ashworth and J L Thompson and J R James and C E Slater and S Pijuan-Galit\'{o} and K Lis-Slimak and R J Holley and K A Meade and A Thompson and K P Arkill and M Tassieri and A J Wright and G Farnie and C L R Merry},

year  = {2020},

date = {2020-01-01},

journal = {Matrix Biol.},

volume = {85-86},

pages = {15\textendash33},

publisher = {Elsevier BV},

abstract = {Current materials used for in vitro 3D cell culture are often 

 limited by their poor similarity to human tissue, batch-to-batch 

 variability and complexity of composition and manufacture. Here, 

 we present a ``blank slate'' culture environment based on a 

 self-assembling peptide gel free from matrix motifs. The gel can 

 be customised by incorporating matrix components selected to 

 match the target tissue, with independent control of mechanical 

 properties. Therefore the matrix components are restricted to 

 those specifically added, or those synthesised by encapsulated 

 cells. The flexible 3D culture platform provides full control 

 over biochemical and physical properties, allowing the impact of 

 biochemical composition and tissue mechanics to be separately 

 evaluated in vitro. Here, we demonstrate that the peptide gels 

 support the growth of a range of cells including human induced 

 pluripotent stem cells and human cancer cell lines. Furthermore, 

 we present proof-of-concept that the peptide gels can be used to 

 build disease-relevant models. Controlling the peptide gelator 

 concentration allows peptide gel stiffness to be matched to 

 normal breast (1 kPa), with higher stiffness favouring the 

 viability of breast cancer cells over normal breast cells. In 

 parallel, the peptide gels may be modified with matrix 

 components relevant to human breast, such as collagen I and 

 hyaluronan. The choice and concentration of these additions 

 affect the size, shape and organisation of breast epithelial 

 cell structures formed in co-culture with fibroblasts. This 

 system therefore provides a means of unravelling the individual 

 influences of matrix, mechanical properties and cell-cell 

 interactions in cancer and other diseases.},

keywords = {biomaterials, Cancer, extracellular matrix, Stem cells, Stiffness},

pubstate = {published},

tppubtype = {article}

}