Reduced expression of platelet endothelial cell adhesion molecule-1 in bone marrow cells in mice after skeletal unloading.

Unlabelled: One week of tail suspension significantly decreased the expression of PECAM-1 in mouse tibial bone marrow cells but not those of a number of other vascular factors. Anti-PECAM-1 antibody suppressed both ALP+ CFU-f formation and ALP production under co-culture of the osteoblastic cell line and the PECAM-1+ endothelial cell line. This study suggests that the reduced ALP activity after skeletal unloading is related to downregulation of PECAM-1 expression in bone marrow cells in mice.

Osteoclast development in immobilized bone is suppressed by parathyroidectomy in mice.

We tested the hypothesis that signaling of parathyroid hormone (PTH) facilitates osteoclastogenesis in bone marrow cells after immobilization, thereby reducing trabecular bone volume. We performed histomorphometric analyses in immobilized limbs after right sciatic neurectomy (IM) and in the contralateral limbs after sham surgery (M). Mice underwent thyroparathyroidectomy (TPTX) and then 0.

Pycnodysostosis associated with spondylolysis.

We report 23 years of observation of a patient with pycnodysostosis associated with progressive spondylolysis. There have been very few papers describing the development of spondylolysis associated with pycnodysostosis as confirmed by serial X-ray examinations. The diagnosis was made by the patient's typical bird-like face, plain radiological findings, and repeated tibial fractures.