Bone Abstracts

Loss of genomic maintenance contributes to aging, as exemplified by mutations in Ercc DNA repair proteins that lead to a plethora of progeroid syndromes of which some display accelerated bone loss. It is generally accepted that dietary restriction (DR) increases life span and improves organ function. We therefore assessed the impact of DR on life span and bone mass in WT and bona fide prematurely aging hypomorphic Ercc-deficient mice (Ercc1−/Δ).<...

In this case report, we present a brother and sister with hereditary vitamin D resistant rickets (HVDRR). Both children presented at the age of 18 months with severe rickets and elevated serum levels of 1,25-(OH)2D3. They differ from each other in that the girl presented with hypophosphatemia instead of hypocalcemia. Besides, she developed alopecia earlier than the boy and needed more 1,25-(OH)2D3 supplementation. Interestingly, the ...

Biographical DetailsM van den Heuvel-Eibrink is Associate Professor of Pediatric Oncology at the Erasmus MC/Sophia Children’s Hospital, Rotterdam, The Netherlands. She began her medical career with an MD from the University of Utrecht and following a number of years of clinical work in the pediatric oncology field completed her PhD in Rotterdam in 2001. Since 2009 Dr M van den Heuvel...

Biographical DetailsHans van LeeuwenHans (J.P.T.M.) van Leeuwen studied biology in Amsterdam, and did his PhD study on the mechanism of action of PTH in Leiden, The Netherlands. Currently he is professor at the Erasmus University Medical Center in Rotterdam, The Netherlands, leading the research program on Calcium and Bone Metabolism. Main research ...

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Communication between osteoblasts and osteoclasts is crucial for bone remodeling. Thrombin and its thrombin receptor (TR; PAR-1) are expressed in osteoclasts and osteoblasts, respectively. To date, the physiological roles of thrombin and TR in bone metabolism have not been elucidated. Therefore, we fully characterized the bone phenotype of mice lacking the thrombin receptor.We performed bone microarchitectural analyses of the femurs of 10–12 week ol...

Transient receptor potential vanilloid channels (TRPVs) have been implicated in Ca2+ homeostasis and bone metabolism. In particular, TRPV4 deficiency was shown to cause sexual dimorphism in bone metabolism and osteoporotic fracture risk. Cortical bone structure was reported to be altered in male TRPV4 knock-out (TRPV4−/−) mice but not in female TRPV−/− mice compared to sex-matched wildtype (TRPV4+/+) animals.To gain knowledge on t...

About two decades ago, evidence was generated that canonical Wnt signaling plays an important role in bone accrual mainly based on the identification of mutations in genes from the Wnt pathway resulting in extremely low or high bone mass. Since then, it became clear that genetic variation in a lot of genes from this pathway have an influence on bone mass both in a number of skeletal dysplasias as well as in the general population. This is the case for a number of wnt ligands (...

Background: This case illustrates the longitudinal improvements quantified by serial bone mineral density scans in an adolescent female with juvenile idiopathic osteoporosis treated with pamidronate.Presenting problem: The girl in question presented at 11 years and 10 months with a 5-month history of increasing back pain. A MRI scan prior to referral had indicated vertebral collapse and osteopenia. She had no medical, social or developmental history of n...

Introduction: The reported prevalence of secondary causes for osteoporosis in men and women aged ≥50 years with a fracture is 35–60%, but data on these causes are scarce in patients with osteopenia and fractures.Objective: To investigate whether secondary causes for osteoporosis are prevalent and may contribute to fracture risk in patients aged ≥50 years with osteopenia and a recent fracture.Materials and methods: ...