Body position differentially influences responses to exogenous and endogenous cues.

The influence of vestibular inputs on exogenous (Exp. 1) and endogenous (Exp. 2) orienting of visual attention was examined. The vestibular system was manipulated through a change in static body position. Participants engaged in an exogenous or endogenous response task while in a seated position, while lying in a prone position, and while in a prone position with their head down and neck flexed (HDNF). An attenuation of inhibition and facilitation effects during the exogenous task was observed in the HDNF position. However, responses to the cues remained similar in the endogenous task, irrespective of body position. The results reveal a potential dissociation between reflexive and volitional orienting of visual attention that is dependent on vestibular inputs.

Osteoblast expression of cytokines is altered on MTA surfaces.

OBJECTIVE: Mineral trioxide aggregate (MTA) is used within areas of periradicular inflammation. Therefore, the purpose of this study was to determine if osteoblasts that attach to MTA surfaces alter their expression of inflammatory cytokines. STUDY DESIGN: Mouse MC3T3-E1 preosteoblasts were seeded onto ProRoot (Pr-MTA) and Tooth-Colored (Tc-MTA) MTA surfaces, as well as commercially pure titanium (cpTi) and tissue culture plastic (TCP) controls. Cell-surface interactions were visualized by inverted fluorescence microscopy. After 24 hours of attachment, the cells were stimulated with bacterial lipopolysaccharide (LPS) and analyzed by reverse-transcription polymerase chain reaction. RESULTS: Numerous cells attached and spread out onto Pr-MTA and Tc-MTA, as they did on cpTi and TCP. They formed plentiful extensions and a spindle-shaped morphology on the granular MTA surfaces. Cells grown on TCP and cpTi expressed an abundance of interleukin (IL-6) and IL-1alpha upon LPS exposure. Cells on Pr-MTA and Tc-MTA produced IL-6 but failed to express IL-1alpha despite LPS stimulation. CONCLUSIONS: Osteoblast expression of inflammatory cytokines is altered on endodontic MTA surfaces compared with titanium implants and plastic controls.