This study was carried out (1) to compare the time-course of the change in bone metabolism in rats administered gonadotrophin-releasing hormone agonist (GnRHa) and bilaterally ovariectomized (OVX) rats and (2) to investigate the changes in bone metabolism after discontinuance of GnRHa. Seventy female Sprague-Dawley rats, aged 90 days, were divided into four groups. Group 1 underwent a sham operation, group 2 was surgically ovariectomized and group 3 was given a GnRHa (leuprorelin acetate for depot suspension) s.c. injection every 30 days. Group 3 was further divided into three subgroups: rats were administered GnRHa for 12 months (GnRHa 12M), 6 months (GnRHa 6M) or 3 months (GnRHa 3M). Group 4 served as a basal control. The bone mineral density (BMD) of lumbar vertebrae and femoral bone, measured by dual-energy X-ray absorptiometry, and the serum bone metabolic parameters were determined every 45-90 days. The bone histomorphometry of lumbar vertebra was measured on days 180 and 360 after surgery. GnRHa 12M rats showed significantly lower BMD of vertebrae and femoral bone, lower bone volume and higher bone turnover compared with sham-operated rats and those with secondary hyperparathyroidism on days 180 and 360. Their time-course for changes in bone metabolism was almost the same as that of OVX rats. GnRHa-discontinued rats showed a recovery of bone turnover. The recovery of BMD in GnRHa 6M rats was smaller than that of GnRHa 3M rats after GnRHa discontinuance. The bone volume for GnRHa 6M rats was significantly lower than that for GnRHa 3M on day 360.
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http://dx.doi.org/10.1677/joe.0.1380115 | DOI Listing |
Injury
January 2025
Professor of Orthopedics - Section Head Trauma & Orthopaedic Surgery, School of Medicine University of Leeds, UK.
The term "fragility fractures of the pelvis" refers to the disruptions of the pelvic ring that are caused by low energy injuries (such as low-level falls or falls from the standing position) in the elderly population (age over 65 years) in the absence of metastatic bone disease. These fractures are increasing in numbers, due to the aging population, particularly in the developed countries, causing significant morbidity and mortality [1]. Although some fracture patterns are stable enough requiring only conservative treatment, other fracture types can cause significant pelvic instability, demanding a more insistent management protocol.
View Article and Find Full Text PDFJMIR Res Protoc
January 2025
Department of Research and Development, Sharad Pawar Dental College, Datta Meghe Institute of Higher Education and Research, Wardha, India.
Background: Injectable platelet-rich fibrin (i-PRF) has the capacity to release great amounts of several growth factors, as well as to stimulate increased fibroblast migration and the expression of collagen, transforming growth factor β, and platelet-derived growth factor. Consequently, i-PRF can be used as a bioactive agent to promote periodontal tissue regeneration.
Objective: We aim to compare and evaluate the effectiveness of i-PRF in periodontal tissue regeneration.
Biomol Biomed
January 2025
Department of Orthognathic Surgery and Maxillofacial Trauma, The Third Affiliated Hospital of Air Force Medical University, Xi'an, China.
Implant failure remains a significant challenge in oral implantology, necessitating a deeper understanding of its risk factors to improve treatment outcomes. This study aimed to enhance the clinical outcomes of oral implant restoration by investigating the factors contributing to implant failure in patients with partial dentition defects within two years of treatment. Additionally, the study sought to develop an early risk prediction model for implant failure.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang 330047, P. R. China.
Food allergy is a complex disease, with multiple environmental factors involved. Considering the regulatory effect of toxin A (Tcd A) on biological processes of allergic reactions, the role of oral exposure to Tcd A on food allergy was investigated. The intestinal permeability and β-hexosaminidase were promoted by Tcd A using the in vitro Caco-2 and HT-29 cells coculture monolayer and bone marrow-derived mast cell (MCs) degranulation model.
View Article and Find Full Text PDFJ Bone Joint Surg Am
January 2025
Harris Orthopaedics Laboratory, Massachusetts General Hospital, Boston, Massachusetts.
Background: Periprosthetic joint infections (PJIs) are a major complication of total joint replacement surgeries. This study investigated the enhancement of mechanical properties and antibiotic release in ultra-high molecular weight polyethylene (UHMWPE) through the encapsulation of submicron gentamicin sulfate (GS) particles, addressing the critical need for improved implant materials in orthopaedic surgery, particularly in managing PJIs.
Methods: The present study involved embedding submicron GS particles into UHMWPE flakes at concentrations of 2% to 10% by weight.
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