Bone Abstracts

Objectives: To find the predicting factors for bone density in premenopausal women.Methods: Two hundred and forty-five premenopausal women without factors that can cause secondary osteoporosis were analyzed. Age, height, weight, change of height from peak height, history (Hx) of fracture, family Hx of hip or other fracture, Hx of estrogen use, calcium or vitamin D supplementation, smoking and previous Hx of amenorrhea more than 3 months were questioned. ...

Introduction: A significant number of patient who have experienced previous surgical treatment for an osteoporotic hip fracture, experienced a subsequent hip fracture (SHF) on the opposite side. The incidence of asynchronous bilateral hip fractures is 1.7–14.8%. All hip fracture patients treated at five university hospitals in the Inchon and Bucheon area of Korea, were reviewed. The patients were divided into two groups, a group that had experienced subsequent hip fractur...

Objectives: To evaluate the effect of hormone therapy on the change of bone mineral density in women who showed early menopause after pelvic radiation therapy for uterine cervical cancer.Materials and methods: Through retrospective chart review, the changes of bone mineral density in 63 women with early menopause after pelvic radiation therapy for uterine cervical cancer were evaluated. After the diagnosis of early menopause which was defined as level of...

Background: Bone accrual during adolescence is the main contributor to peak bone mass. Bone remodeling is a balance between bone formation and resorption as directed by osteoblast and osteoclast activity, respectively. nitric oxide (NO) is a potent regulator of bone remodeling via mediating effects of cytokines, estrogen and mechanical strain. NO is synthesized from the conversion of L-arginine to L-citrulline by the enzyme nitric oxide synthase (...

Background: Mechanical stimulation is thought to be critical for bone anabolic activity. It is unclear how quickly the growing skeleton responds to additional externally-applied mechanical stimuli. We wished to determine the acute effect of a standardised mechanical stimulus to the growing skeleton.Objectives: To determine the acute time course and magnitude of bone’s response to whole body vibration (WBV) in pre-pubertal boys.<p class="abstext"...

This study was performed to characterize the effects of calcium phosphate coated and hydroxyapatite coated zirconia compared to smooth surfaced zirconia with bone marrow-derived osteoblast culture.Bone marrow-derived osteoblasts were cultured on i) smooth zirconia, ii) zirconia coated with calcium phosphate (CaP), and iii) zirconia coated with hydroxyapatite (HA). The tetrazolium-based colorimetric assay (MTT test) was used for examining the attachment o...

Lipid raft microdomains have important role in cellular signaling. Caveolae are a specialized type of lipid rafts that are stabilized by oligomers of caveolin protein. Here we showed that caveolin-1 (Cav-1) is a critical membrane structural protein of osteoclast. In microarray analysis, we found that caveolin-1 was significantly up-regulated by RANKL. Knock-down of Cav-1 in bone marrow derived-macrophage reduced osteoclastogenesis. Consistent with the in vitro results...

Bone remodeling and maintenance require a fine balance between bone formation of osteoblasts and resorption of osteoclasts. Therefore, various skeletal disorders cause by imbalanced differentiation and activities of these cells. RANKL (receptor activator of NF-kB ligand) induces Ca2+ oscillations and activates NFATc1 (nuclear factor of activated T cells i) during osteoclast differentiation. Although Ca2+ oscillations play a key role for osteoclastogenesis...

The P2Y14 (purinergic receptor P2Y, G protein coupled, 14) receptor for UDP-glucose and other UDP-sugars has been implicated in the regulation of the stem cell compartment as well as neuroimmune function. However, the role of P2Y14 in osteoclast formation is completely unknown. We found that RANKL selectively induced P2Y14 among seven mammalian P2Y receptors when analysed at both the mRNA and protein level, but inhibitors of the MAP pathway suppressed induction of P2Y14 protei...

There are several evidences that osteocyte plays a critical role in bone remodeling. Healthy or apoptotic osteocytes can send signals to other bone surface cells like osteoblasts, osteoclasts, osteoclast precursors and bone lining cells through their networking in canaliculi. Therefore, to determine the role for osteocytes in bone remodeling, we examined the effect of healthy and apoptotic osteocytes on osteoblasts proliferation and recruitment. In addition, the effects of mec...