The aim of this study was to evaluate new response metrics based on chemical and biological activity of NP for screening assays that can be used to predict

NP toxicity in vivo. Two cell-free and two cell-based assays were evaluated for their power in predicting 4-Hydroxytamoxifen datasheet in vivo toxicity of eight distinct particle types with widely differing physicochemical characteristics. The cell-free systems comprised fluorescence- and electron spin resonance-based assays of oxidant activity. The cell-based systems also used electron spin resonance (ESR) as well as luciferase reporter activity to rank the different particle types in comparison to benchmark particles of low and high activity. In vivo experiments evaluated acute pulmonary inflammatory responses in rats. Endpoints in all assays were related to oxidative stress and responses were expressed per unit NP surface area to compare the results of different assays. Results indicated that NP

are capable of producing reactive species, which in biological systems lead to oxidative this website stress. Copper NP had the greatest activity in all assays, while TiO2 and gold NP generally were the least reactive. Differences in the ranking of NP activity among the assays were found when comparisons were based on measured responses. However, expressing the chemical (cell-free) and biological (cells; in vivo) activity per unit particle surface area showed that all in vitro assays correlated significantly with in vivo results, with the cellular assays correlating the best. Data from this study indicate that it is possible

to predict acute in vivo inflammatory potential of NP with cell-free and cellular assays by using NP surface area-based dose and response metrics, but that a cellular component is required to achieve a higher degree of predictive power.”
“BACKGROUND: When an anterior approach to repair a burst fracture is indicated, several devices can be used to restore spinal stability (eg, bone graft, free-standing titanium cage, and expandable titanium Florfenicol cage).

OBJECTIVE: We compare the biomechanical stability and prices of each of these systems.

MATERIALS AND METHODS: Eight fresh human cadaver T11 through L3 vertebral specimens were harvested and cleaned of soft tissues. T11-T12 and L2-L3 were fixed by screws. The fixed ends were then set in automotive body filler (Bondo). The prepared specimens were tested in the Biaxial Instron tester (8874, Norwood, MA) after a sequence of the following: intact, after the creation of an anterior corpectomy at L1, and after insertion of both of the 2 different titanium cages and the fibular graft. A titanium screw-and-plate anterolateral system was used to secure the construct (VANTAGE, Medtronic Sofamor Danek, Memphis, TN). The conditions of displacement testing were as follows: rotation (+/- 3.5 degrees), flexion and extension, and left and right bending (+/- 3.5 mm). For each mode of testing, the stiffness was calculated.