Fig. 1.

Histological changes of osteolysis mediated by particle-induced endoplasmic reticulum (ER) stress (TiNPs TiAl6V4 nanoparticles, CoNPs CoCrMo nanoparticles, Tg thapsigargin, 4-PBA 4-phenylbutyrate). a–h Representative microtomography images of the calvaria in each group (arrows calvaria surface corrosion). a’–h’ Toluidine blue staining of the calvaria in each group (arrowheads bone resorption lacunae). Original magnification: ×40. Bar 500 μm. Data represent means ± SEM for each group. *P < 0.05, **P < 0.01 versus control. ^# P < 0.05, ^## P < 0.01 versus TiNPs or CoNPs