Analyses are presented of the ratios of 226Ra to calcium in over 650 samples of compact and cancellous bone from 66 female and 26 male subjects who had died from less than 1 to 60 yr after first exposure to radium. The 226Ra/Ca ratios were normalized to the terminal 226Ra skeletal content. The 226Ra/Ca ratios for vertebrae were essentially identical to those for other cancellous bone for a given subject. Comparisons of the data with predictions of the ICRP model of alkaline earth metabolism show that for female cancellous bone the normalized 226Ra/Ca ratios tended to be greater than predicted, while those for female cortical bone (femoral and tibial shaft) tended to be less. The data for males were fitted better by the model. A modification of the model to reduce the amount of radium deposited in soft tissue fitted the data better in some respects. A straight line linear least squares fit to the data appeared to fit as well as, or better than, the models. A radiation effect was suggested in that the normalized 226Ra/Ca ratio for vertebrae relative to the ratio expected increased with skeletal absorbed dose for vertebrae. However, no such effect was apparent for compact bone or for the cancellous bone as a whole.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1097/00004032-198306001-00010 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Using optimization approach to design dental implant in three types of bone quality - A finite element analysis.
J Dent Sci
January 2025
Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University, Taipei, Taiwan.
Background/purpose: The use of finite element (FE) analysis in implant biomechanics offers many advantages over other approaches in simulating the complexity of clinical situations. The aim of this study was to perform an optimization analysis of dental implants with different thread designs in three types of bone quality.
Materials And Methods: The three-dimensional FE model of a mandibular bone block with a screw-shaped dental implant and superstructure was simulated.
Comparison of Bicortical versus Unicortical Medial Malleolus Fixation.
J Am Podiatr Med Assoc
January 2025
*Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA.
Background: Ankle fractures continue to increase in incidence and severity in an older, more challenging geriatric population. Medial malleolus fixation with partially threaded cancellous 4.0-mm screws, a common fixation method, has been shown to fail due to pullout strength.
View Article and Find Full Text PDFSimulation analysis of surgical neck fractures of the humerus related to bone degeneration.
Comput Methods Biomech Biomed Engin
January 2025
Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.
The most common type of proximal humerus fracture is surgical neck fracture. The purpose of this paper is to study the mechanical mechanism and the effect of bone degeneration on humeral surgical neck fractures. The right humerus finite element models were established based on CT computed tomography.
View Article and Find Full Text PDFChemerin mediates exercise-induced improvements of bone microstructure and bone mass in diabetes or high fat diet mice.
Mol Cell Endocrinol
January 2025
Shanghai University of Sport, School of Health and Exercise, Shanghai 200438, China. Electronic address:
To clarify the roles and mechanisms of adipokine chemerin in exercise-induced bone improvements in type 2 diabetes mellitus (DM) mice and mice fed on high fat diet (HFD). DM mice were established by HFD+streptozotocin injection, exogenous chemerin was supplemented prior to running, and found that exogenous chemerin reversed 6-week exercise-induced improvements in cancellous bone parameters in DM mice. While adipose-specific chemerin knockout improved microstructure and mass of cancellous bone in HFD mice and further increased exercise-induced bone improvements, accompanied with promoted osteogenesis and inhibited osteoclasis represented as the changes of RANKL, M-CSF, Runx2, Osterix, OPG, ALP and CTSK.
View Article and Find Full Text PDFEpiregulin ameliorates ovariectomy-induced bone loss through orchestrating the differentiation of osteoblasts and osteoclasts.
J Bone Miner Res
January 2025
NHC Key Lab of Hormones and Development, Tianjin Key Lab of Metabolic Diseases, Chu Hsien-I Memorial Hospital & Institute of Endocrinology, Tianjin Medical University, Tianjin 300134, China.
Epiregulin plays a role in a range of biological activities including malignancies. This study aims to investigate the potential contribution of epiregulin to bone cell differentiation and bone homeostasis. The data showed that epiregulin expression was upregulated during osteogenesis but downregulated during adipogenesis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!