Normal mineralization and nanostructure of sclerotic bone in mice overexpressing Fra-1.

Increased bone mass due to elevated number of active osteoblasts has been reported for transgenic mice overexpressing the transcription factor Fra-1. To explore the potential of the anabolic action of Fra-1 in treatment of osteoporosis, we examined the integrity of bone matrix generated in Fra-1 transgenic mice. Femora from Fra-1 transgenic (Fra-1 tg) and wild-type littermates were analyzed for bone mineralization density distribution (BMDD) and nanostructure using quantitative backscattered electron imaging (qBEI) and scanning small angle X-ray scattering (scanning-SAXS), respectively.

Decreased bone turnover and deterioration of bone structure in two cases of pycnodysostosis.

Pycnodysostosis is an uncommon human genetic disorder characterized by osteosclerosis of the skeleton, short stature, and bone fragility. The disease results from mutations in the cathepsin K gene, a lysosomal cysteine protease highly expressed in osteoclasts and crucial for the degradation of organic matrix from mineralized bone. Recently, interest has focused on a pharmaceutical inhibition of cathepsin K to prevent bone loss.

Effects of intermittent parathyroid hormone administration on bone mineralization density in iliac crest biopsies from patients with osteoporosis: a paired study before and after treatment.

Anabolic effects of PTH have been observed at several skeletal sites in humans by dual x-ray absorptiometry without differentiating between an actual increase in bone volume and an increase in mineral content within already established bone. The present study addressed this issue by evaluating the bone mineralization density distribution of iliac crest bone biopsies before and after PTH treatment for 18-36 months in men and women with osteoporosis using quantitative backscattered electron imaging. In cortical bone, pairwise comparison of the two biopsies before and after treatment revealed a reduction in the typical calcium concentration in men (-3.

Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue nonspecific alkaline phosphatase.

Tissue nonspecific alkaline phosphatase (TNALP) is thought to play an important role in mineralization processes, although its exact working mechanism is not known. In the present investigation we have studied mineral crystal characteristics in the developing skeleton of TNALP-deficient mice. Null mutants (n = 7) and their wild-type littermates (n = 7) were bred and killed between 8 and 22 days after birth.

Structural development of the mineralized tissue in the human L4 vertebral body.

Knowledge of the structural development of the human vertebrae from non-weight-bearing before birth to weight-bearing after birth is still poor. We studied the mineralized tissue of the developing lumbar L4 vertebral body at ages 15 weeks postconception to 97 years from the tissue level (trabecular architecture) to the material level (micro- and nanostructure). Trabecular architecture was investigated by 2D histomorphometry and the material level was examined by quantitative backscattered electron imaging (for typical calcium content, CaMaxFreq) and scanning small-angle X-ray scattering (for mean mineral particle thickness).

Age- and genotype-dependence of bone material properties in the osteogenesis imperfecta murine model (oim).

Cortical mineralization of long bones was studied in collagen alpha2(I)-deficient mice (oim) used as a model for human osteogenesis imperfecta. Aspects of the age development of the mice were characterized by combining nanometer- to micrometer-scale structural analysis with microhardness measurements. Bone structure was determined from homozygous (oim/oim) and heterozygous (oim/+) mice and their normal (+/+) littermates as a function of animal age by small-angle X-ray scattering (SAXS) and quantitative backscattered electron imaging (qBEI) measurements.