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The National Joint Registry reported that the main causes for hip implant revision surgery include aseptic loosening, infection and adverse soft tissue reaction to particulate debris. There is a great need to improve the implant properties which can be achieved through a combined solution of beta titanium alloy (TNZT) with low elastic modulus and laser surface nitriding to improve mechanical properties and biological response. While titanium nitride (TiN) possesses good biocompatibility and remarkable antibacterial properties; its effectiveness as a coating on Ti-35Nb-7Zr-6Ta has not been investigated in relation to stem cell response and antibacterial capability. TNZT surfaces were laser-nitrided in incremental power, specifically 35, 40 and 45 W. Investigation included surface roughness and topography in microscale (WLI and SEM), microstructure (XRD) and wettability (water contact angle).Biological studies of the laser-nitrided surfaces included in vitro culture for 24 hours using mesenchymal stem cell (MSC) fluorescence staining and Staphylococcus aureus (S. aureus) Live/Dead staining. Sample groups consisted of control base metal (BM), laser-nitrided at 35 W (LT35), 40 W (LT40) and 45 W (LT45). Results revealed that laser nitriding generates significantly rougher surfaces (Ra value of BM was 199 nm, LT35 was 723 nm, LT40 was 458 nm and LT45 was 1180 nm) with distinctive surface features (Rsk < 0 and Rku > 3). Surfaces after laser nitriding, regardless of laser power, can be tailored to become hydrophilic (27 -34°).Fibre laser nitriding can be used to create antibacterial surface patterns on TNZT in a high power regime. A laser power of 45 W proved to be the most effective in this study, creating an overlapping crescent shape which becomes more obvious with increasing power. To summarise, laser-nitrided surfaces led to a significant antibacterial effect but offered no particular advantage to MSC response.

Clinical data are now emerging confirming the promise of the initial preclinical data that demonstrated superior efficacy of obinutuzumab over rituximab at similar dosing. The emerging randomized Phase III data from older comorbid patients with previously untreated CLL demonstrated significant improvements in molecular remission rates and median progression-free survival of obinutuzumab plus chlorambucil versus rituximab plus chlorambucil. This emerging data provide reasons to be optimistic that outcomes for patients with B-cell malignancies can be further improved with obinutuzumab.

A mismatch in bone and implant elastic modulus can lead to aseptic loosening and ultimately implant failure. Selective elemental composition of titanium (Ti) alloys coupled with surface treatment can be used to improve osseointegration and reduce bacterial adhesion. The biocompatibility and antibacterial properties of Ti-35Nb-7Zr-6Ta (TNZT) using fibre laser surface treatment were assessed in this work, due to its excellent material properties (low Young’s modulus and non-toxicity) and the promising attributes of fibre laser treatment (very fast, non-contact, clean and only causes changes in surface without altering the bulk composition/microstructure). The TNZT surfaces in this study were treated in a high speed regime, specifically 100 and 200 mm/s, (or 6 and 12 m/min). Surface roughness and topography (WLI and SEM), chemical composition (SEM-EDX), microstructure (XRD) and chemistry (XPS) were investigated. The biocompatibility of the laser treated surfaces was evaluated using mesenchymal stem cells (MSCs) cultured in vitro at various time points to assess cell attachment (6, 24 and 48 h), proliferation (3, 7 and 14 days) and differentiation (7, 14 and 21 days). Antibacterial performance was also evaluated using Staphylococcus aureus (S. aureus) and Live/Dead staining. Sample groups included untreated base metal (BM), laser treated at 100 mm/s (LT100) and 200 mm/s (LT200). The results demonstrated that laser surface treatment creates a rougher (Ra value of BM is 199 nm, LT100 is 256 nm and LT200 is 232 nm), spiky surface (Rsk > 0 and Rku > 3) with homogenous elemental distribution and decreasing peak-to-peak distance between ripples (0.63 to 0.315 µm) as the scanning speed increases (p < 0.05), generating a surface with distinct micron and nano scale features. The improvement in cell spreading, formation of bone-like nodules (only seen on the laser treated samples) and subsequent four-fold reduction in bacterial attachment (p < 0.001) can be attributed to the features created through fibre laser treatment, making it an excellent choice for load bearing implant applications. Last but not least, the presence of TiN in the outermost surface oxide might also account for the improved biocompatibility and antibacterial performances of TNZT.