Development of a new radioimmunoassay for human osteocalcin: Evidence for a midmolecule epitope

Taylor, A.; Linkhart, Susan G.; Mohan, Subburaman; Baylink, David J.

doi:10.1016/0026-0495(88)90122-9

Cited by 58 publications

(20 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PTH was measured using a 2-site immunoradiometric assay that detects only intact PTH (ie, biologically active 84-amino-acid peptide) (20). Total OCN level was measured using a mid-molecule-specific RIA for human OCN (21). BAP was measured spectrophotometrically after heat inactivation (22).…”

Section: Measurementmentioning

confidence: 99%

A Cross-Sectional Association Between Bone Mineral Density and Parathyroid Hormone and Other Biomarkers in Community-Dwelling Young Adults: The CARDIA Study

Fujiyoshi

Polgreen²,

Hurley

et al. 2013

The Journal of Clinical Endocrinology &Amp; Metabolism

View full text Add to dashboard Cite

In this cross-sectional study of healthy young men and women who had PTH levels considered normal in clinical practice, higher PTH was associated with lower BMD, particularly in weight-bearing sites (ie, spine and hip). The inverse association of 1,25(OH)2D, together with the attenuation of PTH, suggests that the observed association of PTH is mediated by 1,25(OH)2D. BAP was inversely associated with arm BMD. BBMs can be important markers of skeletal activity in young adults, but their clinical role on bone health among this population is yet to be fully determined.

show abstract

Section: Measurementmentioning

confidence: 99%

A Cross-Sectional Association Between Bone Mineral Density and Parathyroid Hormone and Other Biomarkers in Community-Dwelling Young Adults: The CARDIA Study

Fujiyoshi

Polgreen²,

Hurley

et al. 2013

The Journal of Clinical Endocrinology &Amp; Metabolism

View full text Add to dashboard Cite

show abstract

“…Osteocalcin was assayed with a radioimmunoassay specific for the mid-molecule human osteocalcin (Taylor et al, 1988). Because normal human mandible-derived bone cells did not secrete detectable amounts of osteocalcin under basal conditions, the effect of phenytoin was tested in the presence of 10-8 M 1,25-dihydroxyvitamin D3.…”

Section: Cellular Alp Specific Activity Assaymentioning

confidence: 99%

Phenytoin at Micromolar Concentrations is an Osteogenic Agent for Human-mandible-derived Bone Cells in vitro

1995

View full text Add to dashboard Cite

The present study sought to test the hypothesis that phenytoin acts on normal human-mandible-derived bone cells to induce osteogenic effects. To test the effects of phenytoin on bone cell proliferation, we measured [3H]-thymidine incorporation into cell DNA during the final four hr of a 24-hour incubation with phenytoin. Phenytoin at micromolar concentrations significantly stimulated the [3H]-thymidine incorporation in a dose-dependent, biphasic, manner with a maximal effect at from 10 to 50 microM. We confirmed the proliferative effect of phenytoin by counting cell number. To evaluate the effects of phenytoin on osteoblastic differentiation, we determined alkaline-phosphatase specific activity and found that phenytoin at micromolar concentrations significantly increased that activity in a dose-dependent manner, with maximal stimulation at approximately 1 microM. To investigate the effects of phenytoin on mature osteoblastic activities, we measured de novo collagen synthesis and osteocalcin secretion. Mitogenic doses of phenytoin significantly increased collagen synthesis and osteocalcin secretion in a dose-dependent, biphasic, manner, with the maximal stimulatory dose at from 5 to 10 microM. In summary, phenytoin at micromolar ranges increased (a) [3H]-thymidine incorporation and cell number, (b) alkaline-phosphatase specific activity, (c) collagen synthesis, and (d) osteocalcin secretion in monolayer cultures of normal human-mandible-derived bone cells. These observations are consistent with the premise that low doses of phenytoin act on human craniofacial bone cells to stimulate cell proliferation, differentiation, and mature osteoblastic activities to stimulate bone formation.

show abstract

“…The lower serum OC level that occurs during diurnal hours in our SNC could result from a reduced osteoblast production of intact OC or from an increased osteoblast catabolism of pro-Of'; We are not able to verify these suppositions because we measured serum OC concentrations by using rabbit anti bovine OC antibody that recognizes a major epitope near the carboxyterminal portion of the molecule detecting both intact DC and carboxyterminal fragments of the molecule (45,46); therefore, the method we used is unable to detect intact OC molecules alone or measure pro-OC peptide . Alternatively, the apparent normality of nighttime DC data in SNC could be related to increased bone resorption during nocturnal hours, because a fraction of immunoreactive DC fragments are released into blood during bone resorption by osteoclast, and the method to measure serum OC concentrations that we used also detects these fragments (16,(44)(45)(46). In contrast to our results, Markowitz et al (30) in four children with idiopathic short stature demonstrated a reduced DC pattern during either daytime or nighttime using the same RIA we used.…”

Section: Ocmentioning

confidence: 99%

Twenty-four-Hour Osteocalcin, Carboxyterminal Propeptide of Type I Procollagen, and Aminoterminal Propeptide of Type III Procollagen Rhythms in Normal and Growth-Retarded Children

et al. 1994

View full text Add to dashboard Cite

ABSTRACf. The relationships between spontaneous variations in serum 24-h osteocalcin (DC), carboxyterminal propeptide of type I procollagen (PICP), and aminoterminal propeptide of type III procollagen (PIIINP) concentrations and GH secretion, measured as GH response to provocative pharmacologic stimuli and spontaneous GH secretion during 24 h, were evaluated in prepubertal normal children and in GH-deficient and GH-secreting short normal children (SNC). All the subjects showed a circadian rhythm in smoothed 24-h DC and PICP mean data with higher nocturnal values in comparison with diurnal values. Conversely, serum PIIINP concentrations did not vary throughout the day. In children with classic GH deficiency and nonclassic GH deficiency, mean 24-h serum levels and smoothed 24-h mean data for DC, PICP, and PIIINP were significantly reduced (p < 0.001) with respect to agematched controls. SNC showed mean 24-h DC concentrations similar (p = NS) to those we found in age-matched controls, but they had significantly lower (p < 0.001) diurnal 12-h mean data in comparison with controls. SNC also showed both 24-h PICP and PIIINP mean data and smoothed 24-h PICP and PIIINP mean data significantly lower (from p < 0.02 to p < 0.001) at all the time points of measurement in comparison with controls. Twenty-fourhour PICP and PIIINP mean data were positively related to spontaneous 24-h GH concentrations (r = 0.77, p < 0.005 and r =0.69, p < 0.005, respectively) and growth velocity (r =0.85, p < 0.005, and r =0.70, p < 0.005, respectively), whereas 24-h DC mean data were not. Our study suggests that circadian serum PICP and PIIINP concentrations show GH dependency in children with classic GH deficiency and those with nonclassic GH deficiency, but this was less evident in SNC. Serum PICP and PIIINP concentrations may reflect somatic growth in children with short stature that is or is not related to GH deficiency. tPediatr Res 35: 409-415, 1994) Abbreviations PIIINP, aminoterminal propeptide of type III procollagen PICP, carboxyterminal propeptide of type I procollagen

show abstract

Development of a new radioimmunoassay for human osteocalcin: Evidence for a midmolecule epitope

Cited by 58 publications

References 18 publications

A Cross-Sectional Association Between Bone Mineral Density and Parathyroid Hormone and Other Biomarkers in Community-Dwelling Young Adults: The CARDIA Study

A Cross-Sectional Association Between Bone Mineral Density and Parathyroid Hormone and Other Biomarkers in Community-Dwelling Young Adults: The CARDIA Study

Phenytoin at Micromolar Concentrations is an Osteogenic Agent for Human-mandible-derived Bone Cells in vitro

Twenty-four-Hour Osteocalcin, Carboxyterminal Propeptide of Type I Procollagen, and Aminoterminal Propeptide of Type III Procollagen Rhythms in Normal and Growth-Retarded Children

Contact Info

Product

Resources

About