In this study the mechanisms by which sex steroids influence body growth were investigated. The effect of different doses of testosterone propionate on longitudinal bone growth and body weight gain was studied in a) gonadectomized male rats, b) gonadohypophysectomized male rats, and c) gonadohypophysectomized male rats given replacement therapy with bovine growth hormone (bGH). The effect of different doses of estradiol benzoate on the same growth parameters was studied in female rats divided into the same experimental groups as the males. Accumulated longitudinal bone growth was determined using oxytetracycline as an intravital marker. Testosterone caused a dose-dependent increase in longitudinal bone growth in gonadectomized male rats. In contrast, testosterone exerted no significant increase in longitudinal bone growth in gonadohypophysectomized male rats with and without bGH replacement therapy. Treatment with estrogen inhibited longitudinal bone growth and body weight gain. The inhibitory effect of estradiol was approximately the same in gonadohypophysectomized female rats given bGH replacement therapy as in gonadectomized female rats. The results suggest that testosterone exerts its stimulatory effect on body growth mainly by modulating hypothalamopituitary functions, e.g., by altering the secretory pattern of GH. On the other hand, it seems that changes in the hypothalamopituitary functions are less significant for the inhibitory effect of estradiol on body growth. It is concluded from this study that the sites of action for estrogen and testosterone in modulating body growth in the rat are different.
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http://dx.doi.org/10.1152/ajpendo.1983.244.2.E135 | DOI Listing |
J Vet Dent
January 2025
Department of Dentistry, Oral and Maxillo-facial Surgery, Eastcott Veterinary Referrals, Part of Linnaeus Group, Swindon, UK.
Canine acanthomatous ameloblastoma (CAA) is an invasive benign epithelial odontogenic tumour most commonly affecting the mandible of large breed dogs. To the author's knowledge, this report describes the first computer-aided design patient-specific implant (PSI) that has been placed for a critical sized bone defect in mandibular reconstruction of a dog in the UK. The aim was to restore mandibular stability using a regenerative approach combining a titanium locking plate and compression-resistant matrix infused with recombinant human bone morphogenetic protein-2 (rhBMP-2) to bridge the 85 mm mandibular defect created by a segmental mandibulectomy.
View Article and Find Full Text PDFOsteoporos Sarcopenia
December 2024
Osteoporosis and Bone Metabolism Unit, Department of Endocrinology, Singapore General Hospital, Singapore.
Osteoporosis in men remains a significantly underrecognized condition, with notable differences in bone mineral density (BMD) and fracture risk between Asian and Western populations. Despite 30% of hip fractures globally occurring in men, they are less likely to be diagnosed or treated for osteoporosis, especially in resource-limited settings. Given these disparities, a deeper understanding of osteoporosis epidemiology and treatment efficacy in men is essential, particularly in Asian populations.
View Article and Find Full Text PDFJ Clin Rheumatol
January 2025
From the Department of Rheumatology, Brooke Army Medical Center, Fort Sam Houston, TX.
Background: In this case series, we present longitudinal imaging surveillance of 6 cases of osseous sarcoidosis, each of which was effectively treated with tumor necrosis factor (TNF) inhibition.
Methods: We identified 6 patients from Brooke Army Medical Center with osseous sarcoidosis, who were treated with TNF inhibition and followed with longitudinal imaging studies. Cases of osseous sarcoidosis were defined as having pathologic evidence of noncaseating granulomas on bone biopsy and evidence of osseous lesions on imaging attributable to sarcoidosis by the radiologist, treating clinician, and reviewer.
Bone
January 2025
Institute of Sports Medicine Copenhagen (ISMC), Department of Orthopedic Surgery M81, Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Neurology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Denmark; Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
Objectives: Maintained bone health is critical for independent living when aging. Currently, multimodal exercise regimes including weight-bearing exercises with impact are prescribed as optimal for maintaining bone health, while there is less consensus on the effects of resistance training at different intensities upon bone. Here we examined whether bone health was positively influenced by 1 year of supervised resistance training at two different intensities.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Selmi 3, Bologna, 40126, Italy.
The rate of sexual dimorphism in the human hip bone is primarily due to the structural demands of childbirth. Genetic, environmental, and socio-cultural factors can also influence pelvic shape variations across populations. This study examines intra-population sex variation within the Italian population based on regional differences of 280 coxal bones from two documented human osteological collections (Bologna and Sassari) coming from different geographical areas, the northern continental and island regions.
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