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The bone regeneration and healing effect of formononetin was evaluated in a cortical bone defect model that predominantly heals by intramembranous ossification. For this study, female Balb/c mice were ovariectomised (OVx) and a drill-hole injury was generated in the midfemoral bones of all animals. Treatment with formononetin commenced the day after and continued for 21 d. Parathyroid hormone (PTH1-34) was used as a reference standard. Animals were killed at days 10 and 21. Femur bones were collected at the injury site for histomorphometry studies using microcomputed tomography (μCT) and confocal microscopy. RNA and protein were harvested from the region surrounding the drill-hole injury. For immunohistochemistry, 5 µm sections of decalcified femur bone adjoining the drill-hole site were cut. μCT analysis showed that formononetin promoted bone healing at days 10 and 21 and the healing effect observed was significantly better than in Ovx mice and equal to PTH treatment in many aspects. Formononetin also significantly enhanced bone regeneration as assessed by calcein-labelling studies. In addition, formononetin enhanced the expression of osteogenic markers at the injury site in a manner similar to PTH. Formononetin treatment also led to predominant runt-related transcription factor 2 and osteocalcin localisation at the injury site. These results support the potential of formononetin to be a bone-healing agent and are suggestive of its promising role in the fracture-repair process.

Bacterial attachment and biofilm formation on implant surface has been a major concern in hospital and industrial environment. Prevention of bacterial infections of implant surface through surface treatment could be a potential solution and hence this has become a key area of research. In the present study, the antibacterial and biocompatible properties of femtosecond laser surface treated 45S5 bioactive glass (BG) have been investigated. Adhesion and sustainability of both gram positive S. aureus and gram negative P.aeruginosa and E. coli nosocomial bacteria on untreated and laser treated BG samples has been explored. An imprint method has been used to visualize the growth of bacteria on the sample surface. We observed complete bacterial rejection potentially reducing risk of biofilm formation on laser treated surface. This was correlated with surface roughness, wettability and change in surface chemical composition of the samples before and after laser treatment. Biocompatibility of the laser treated BG was demonstrated by studying the anchoring and growth of human cervix cell line INT407. Our results demonstrate that, laser surface modification of BG enables enhanced bacterial rejection without affecting its biocompatibility towards growth of human cells on it. These results open a significantly potential approach towards use of laser in successfully imparting desirable characteristics to BG based bioimplants and devices.

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Low temperature, fast deposition of metallic titanium nitride films using plasma activated reactive evaporation J. Vac. Sci. Technol. A 23, 394 (2005); 10.1116/1.1874152 X-ray diffraction study on residual stress and preferred orientation in thin titanium films subjected to a high ion flux during deposition J. Appl. Phys. 96, 7202 (2004); 10.1063/1.1814413Structural and optical properties of thin zirconium oxide films prepared by reactive direct current magnetron sputtering Titanium nitride thin films have been deposited using reactive direct current magnetron sputtering onto stainless steel substrates. The only deposition condition which has been varied is the ratio of argon to nitrogen in the sputtering gas. While the films deposited at low nitrogen partial pressures exhibited a strong ͑111͒ preferred orientation, with increasing fraction of nitrogen in the sputtering gas, the preferred orientation of the films changed from ͑111͒ to ͑002͒. The accompanying changes in the microstructure and growth morphologies of the phases in these thin films have been investigated by x-ray diffraction and transmission electron microscopy. In addition, the effect of orientation on the optical reflectance of the films has been investigated.