Page 99 - Physico-Chemical Niche Conditions for Bone Cells

illustrated by 3D-images. The highest fluid velocity magnitude was detected at 0.25 sec, and every second thereafter, while the lowest fluid velocity magnitude was observed at 0.75 s, and every second thereafter. (D) The average fluid velocity was oscillating between 0 and 5 mm/s at each pulse. (E) The fluid velocity on the apex was oscillating between 0 and 10 mm/s at each pulse. The magnitude of fluid velocity on the apex of the pre-osteoblast was 2-fold higher than the average fluid velocity on the pre- osteoblast at all time-points measured. (F) FE modeling of fluid pressure distribution on the pre- osteoblast illustrated by 3D-images. The highest fluid pressure magnitude was detected at 0.25 sec, and every second thereafter, while the lowest fluid pressure magnitude was observed at 0.75 sec, and every second thereafter. (G) The average fluid pressure on the cell was oscillating between 0 and 212 Pa at each pulse. (H) The fluid pressure on the apex of the cell was oscillating between 0 and 212 Pa at each pulse, which was similar to the average fluid pressure on the cell at all time-points measured. (I) FE modeling of fluid shear stress on the pre-osteoblast illustrated by 3D-images. The highest fluid shear stress magnitude was detected at 0.25 sec, and every second thereafter, while the lowest fluid shear stress magnitude was observed at 0.75 sec, and every second thereafter. (J) The average fluid shear stress on the cell was oscillating between 0 and 1.16 Pa at each pulse. (K) The fluid shear stress on the apex of the cell was oscillating between 0 and 0.8 Pa at each pulse. The magnitude of the average fluid shear stress on the cell was 1.5-fold higher than the magnitude of fluid shear stress on the apex of the cell all time-points measured. Black arrows: direction of fluid flow; Surface color: magnitude.
Cell morphology
Control and PFF-treated cells attached to the glass slides showed protruding filamentous pseudopodia and were spread well (Fig. 3F, G). Cells displayed very few pseudopodia in static control and 1 h PFF treatment (black arrows). The length of the pseudopodia was not significantly affected by 1 h PFF (Fig. 3H). PFF modulated the shape of the cell body, i.e. cell bodies (PFF) seemed more elliptical (ratio of length/width=1.85±0.13) compared to the static control cells (ratio of length/width=1.74±0.20; Fig. 3I).
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