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991.
Expression of CD105 and CD34 receptors controls BMP‐induced in vitro mineralization of mouse adipose‐derived stem cells but does not predict their in vivo bone‐forming potential 下载免费PDF全文
Vedavathi Madhu Allison Kilanski Nikitha Reghu Abhijit S. Dighe Quanjun Cui 《Journal of orthopaedic research》2015,33(5):625-632
992.
Intramembranous bone regeneration differs among common inbred mouse strains following marrow ablation 下载免费PDF全文
Meghan M. Moran Amarjit S. Virdi Kotaro Sena Steven R. Mazzone Margaret A. McNulty Dale R. Sumner 《Journal of orthopaedic research》2015,33(9):1374-1381
Various intact and post‐injury bone phenotypes are heritable traits. In this study, we sought to determine if intramembranous bone regeneration following marrow ablation differed among common inbred mouse strains and to identify how early the differences appear. We found a ~four‐fold difference in the regenerated bone volume 21 days after marrow ablation in females from four inbred mouse strains: FVB/N (15.7 ± 8.1%, mean and standard deviation), C3H/He (15.5 ± 4.2%), C57BL/6 (12.2 ± 5.2%), and BALB/c (4.0 ± 4.4%); with BALB/c different from FVB/N (p = 0.007) and C3H/He (p = 0.002). A second experiment showed that FVB/N compared to BALB/c mice had more regenerated bone 7 and 14 days after ablation (p < 0.001), while at 21 days FVB/N mice had a greater fraction of mineralizing surface (p = 0.008) without a difference in mineral apposition rate. Thus, differences among strains are evident early during intramembranous bone regeneration following marrow ablation and appear to be associated with differences in osteogenic cell recruitment, but not osteoblast activity. The amount of regenerating bone was not correlated with other heritable traits such as the intact bone phenotype or soft tissue wound healing, suggesting that there may be independent genetic pathways for these traits. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1374–1381, 2015. 相似文献
993.
Resurfacing of the humeral head: An analysis of the bone stock and osseous integration under the implant 下载免费PDF全文
Florian Schmidutz Christoph M. Sprecher Stefan Milz Frank Gohlke Ralph Hertel Volker Braunstein 《Journal of orthopaedic research》2015,33(9):1382-1390
Cementless‐surface‐replacement‐arthroplasty (CSRA) of the shoulder aims for functional joint restoration with minimal bone loss. Good clinical results have been reported, but due to the radiopaque metal shell no data is available on the structure, osseous integration, and bone stock under the implant. 14 hemi‐CSRAs (4 manufacturers) with two geometries (crown [n = 7]/ stem [n = 7] fixation) were retrieved from patients undergoing revision due to glenoidal erosion. Histological sections cutting through the implant centre and bone were analysed. Quantitative histomorphometry evaluated the bone‐implant‐contact and compared the bone‐area to native humeral retrievals (n = 7). The bone‐implant‐interface was further assessed by scanning‐electron‐microscopy (SEM) and energy‐dispersive‐x‐ray (EDX). Qualitative histology revealed a reduced and inhomogeneous bone stock. Obvious signs of stress shielding were observed with bone predominantly visible at the stem and implant rim. Quantitative histomorphometry confirmed the significantly reduced bone‐area (9.2 ± 3.9% [crown 9.9 ± 4.3%, stem 8.6 ± 3.6%]) compared to native humeri (21.2 ± 9.1%; p < 0.05). Bone‐implant‐contact was 20.5 ± 5.8% (crown 21.8 ± 6.2%, stem 19.2 ± 5.6%) which was confirmed by SEM and EDX. Altogether, CRSA shows satisfactory bone ingrowth at the interface suggesting sufficient primary stability to allow osseous integration. However, clear signs of stress shielding with an inhomogeneous and reduced bone stock were observed. The impact on the long‐term‐results is unclear requiring further investigation. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1382–1390, 2015. 相似文献
994.
Prognostic role of nuclear factor/IB and bone remodeling proteins in metastatic giant cell tumor of bone: A retrospective study 下载免费PDF全文
Irene Quattrini Serena Pollino Laura Pazzaglia Amalia Conti Chiara Novello Cristina Ferrari Elettra Pignotti Piero Picci Maria Serena Benassi 《Journal of orthopaedic research》2015,33(8):1205-1211
Giant cell tumor of bone (GCTb) represents 5% of bone tumors, and although considered benign, 5% metastasize to the lung. The expression of proteins directly or indirectly associated with osteolysis and tumor growth was studied on 163 samples of GCTb. Of these, 33 patients developed lung metastasis during follow‐up. The impact of tumor–host interaction on clinical aspects was evaluated with the aim of finding specific markers for new biological therapies, thus improving clinical management of GCTb. Protein expression was evaluated by immunohistochemical analysis on Tissue Microarray. The majority of GCTb samples from patients with metastatic disease were strongly positive to RANKL and its receptor RANK as well as to CAII and MMP‐2 and to pro‐survival proteins NFIB and c‐Fos. Kaplan–Meier analysis indicated a significant difference in metastasis free survival curves based on protein staining. Interestingly, the statistical correlation established a strong association between all variables studied with a higher τ coefficient for RANK/RANKL, RANK/NFIB, and RANKL/NFIB pairs. At multivariate analysis co‐overexpression of NFIB, RANK and RANKL significantly increased the risk of metastasis with an odds ratio of 13.59 (95%CI 4.12–44.82; p < 0.0005). In conclusion, the interconnection between matrix remodeling and tumor cell activity may identify tumor–host endpoints for new biological treatments. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1205–1211, 2015. 相似文献
995.
Use of high resolution dual‐energy x‐ray absorptiometry‐region free analysis (DXA‐RFA) to detect local periprosthetic bone remodeling events 下载免费PDF全文
J. Mark Wilkinson Richard M. Morris Miguel A. Martin‐Fernandez Jose M. Pozo Alejandro F. Frangi Marci Maheson Lang Yang 《Journal of orthopaedic research》2015,33(5):712-716
Dual‐energy x‐ray absorptiometry (DXA) is the gold standard method for measuring periprosthetic bone remodeling, but relies on a region of interest (ROI) analysis approach. While this addresses issues of anatomic variability, it is insensitive to bone remodeling events at the sub‐ROI level. We have validated a high‐spatial resolution tool, termed DXA‐region free analysis (DXA‐RFA) that uses advanced image processing approaches to allow quantitation of bone mineral density (BMD) at the individual pixel (data‐point) level. Here we compared the resolution of bone remodeling measurements made around a stemless femoral prosthesis in 18 subjects over 24 months using ROI‐based analysis versus that made using DXA‐RFA. Using the ROI approach the regional pattern of BMD change varied by region, with greatest loss in ROI5 (20%, p < 0.001), and largest gain in ROI4 (6%, p < 0.05). Analysis using DXA‐RFA showed a focal zone of increased BMD localized to the prosthesis–bone interface (30–40%, p < 0.001) that was not resolved using conventional DXA analysis. The 20% bone loss observed in ROI5 with conventional DXA was resolved to a focal area adjacent to the cut surface of the infero‐medial femoral neck (up to 40%, p < 0.0001). DXA‐RFA enables high resolution analysis of DXA datasets without the limitations incurred using ROI‐based approaches. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:712–716, 2015. 相似文献
996.
Allison L Kuipers Heartley Egwuogu Rhobert W Evans Alan L Patrick Ada Youk Clareann H Bunker Joseph M Zmuda 《Journal of bone and mineral research》2015,30(12):2215-2220
Poor renal function is associated with increased rates of bone loss and osteoporotic fractures in Caucasian men. The importance of kidney function for skeletal health in African ancestry men, who are a population segment with a high prevalence of chronic kidney disease as well as high peak bone mass, is not well known. We examined the relationship between estimated glomerular filtration rate (eGFR) and rates of bone loss in a large population cohort of otherwise healthy Afro‐Caribbean men aged 40 years and older. Dual X‐ray absorptiometry of the proximal femur and quantitative computed tomography of the proximal radius and tibia were obtained approximately 6 years apart. We calculated eGFR from serum creatinine that was measured in fasting samples in 1451 men. Impaired kidney function (IKF, eGFR<60 ml/min/1.7 m2) was observed in 8.6% of the cohort. The relationship between IKF and baseline BMD and annualized rate of change in BMD was analyzed controlling for potentially important confounders. IKF was not associated with baseline BMD. In contrast, men with IKF experienced a rate of decline in areal BMD at the total hip, femoral neck and trochanter and cortical volumetric BMD compared to those with normal kidney function (p<0.05 for all). Impaired kidney function was not associated with changes in trabecular volumetric BMD. In conclusion, poorer kidney function is associated with accelerated bone loss among otherwise healthy Afro‐Caribbean men even after controlling for age and other important medical and lifestyle related variables. © 2015 American Society for Bone and Mineral Research. 相似文献
997.
998.
Dysregulated TGF‐β signaling alters bone microstructure in a mouse model of Loeys‐Dietz syndrome 下载免费PDF全文
Ashvin K. Dewan Ryan E. Tomlinson Stuart Mitchell Brian C. Goh Rachel M. Yung Sarvesh Kumar Eric W. Tan Marie‐Claude Faugere Harry C. Dietz III Thomas L. Clemens Paul D. Sponseller 《Journal of orthopaedic research》2015,33(10):1447-1454
Loeys‐Dietz syndrome (LDS) is a connective tissue disorder characterized by vascular and skeletal abnormalities resembling Marfan syndrome, including a predisposition for pathologic fracture. LDS is caused by heterozygous mutations in the genes encoding transforming growth factor‐β (TGF‐β) type 1 and type 2 receptors. In this study, we characterized the skeletal phenotype of mice carrying a mutation in the TGF‐β type 2 receptor associated with severe LDS in humans. Cortical bone in LDS mice showed significantly reduced tissue area, bone area, and cortical thickness with increased eccentricity. However, no significant differences in trabecular bone volume were observed. Dynamic histomorphometry performed in calcein‐labeled mice showed decreased mineral apposition rates in cortical and trabecular bone with normal numbers of osteoblasts and osteoclasts. Mechanical testing of femurs by three‐point bending revealed reduced femoral strength and fracture resistance. In vitro, osteoblasts from LDS mice demonstrated increased mineralization with enhanced expression of osteoblast differentiation markers compared with control cells. These changes were associated with impaired TGF‐β1–induced Smad2 and Erk1/2 phosphorylation and upregulated TGF‐β1 ligand mRNA expression, compatible with G357W as a loss‐of‐function mutation in the TGF‐β type 2 receptor. Paradoxically, phosphorylated Smad2/3 in cortical osteocytes measured by immunohistochemistry was increased relative to controls, possibly suggesting the cross‐activation of TGF‐β–related receptors. The skeletal phenotype observed in the LDS mouse closely resembles the principal structural features of bone in humans with LDS and establishes this mouse as a valid in vivo model for further investigation of TGF‐β receptor signaling in bone. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1447–1454, 2015. 相似文献
999.
Comparison of volumetric bone mineral density in the operated and contralateral knee after anterior cruciate ligament and reconstruction: A 1‐year follow‐up study using peripheral quantitative computed tomography 下载免费PDF全文
Annegret Mündermann Nina Payer Gernot Felmet Hartmut Riehle 《Journal of orthopaedic research》2015,33(12):1804-1810
1000.
Intermittent PTH administration and mechanical loading are anabolic for periprosthetic cancellous bone 下载免费PDF全文
Matthew J. Grosso Hayden‐William Courtland Xu Yang James P. Sutherland Kirsten Stoner Joseph Nguyen Anna Fahlgren F. Patrick Ross Marjolein C. H. van der Meulen Mathias P. Bostrom 《Journal of orthopaedic research》2015,33(2):163-173