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971.
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Summary

FRAXR incrementally improved prediction of incident major osteoporotic fractures compared with the simplified Canadian Association of Radiologists and Osteoporosis Canada (CAROC) tool.

Introduction

There is debate over the value of seemingly more complex fracture prediction tools over simpler fracture prediction tools. FRAXR and the simplified CAROC tool are both widely used in Canada for estimating 10-year probability of major osteoporotic fractures. We compared the performance of these tools for predicting fracture outcomes.

Methods

Using a bone densitometry registry for Manitoba, Canada, we identified 34,060 individuals age ≥50 years not receiving anti-osteoporosis therapy. Fracture Risk Assessment (FRAX) and CAROC were used to classify 10-year fracture risk as low (<10 %), moderate (10–20 %) and high (>20 %). Net reclassification improvement (NRI) was used to quantify the performance of FRAX versus CAROC.

Results

During mean 9.8 years of follow-up, 3905 individuals sustained fractures. There were 10 (of 35 total) situations where observed fracture risk fell outside of the predicted range, and all 10 discordances favoured FRAX. NRI among incident fracture cases was not significantly changed, but there was a significant improvement in risk categorization for those who remained fracture-free (+1.7 %, P?<?0.001) resulting in overall improvement (NRI overall +0.028, P?<?0.001). Within nine pre-specified subgroups, there was no case of significant worsening in NRI when using FRAX instead of CAROC. In absolute terms, only 36 individuals would need to be assessed using FRAX instead of CAROC to yield an improvement in prediction (8 among individuals with prior fracture and 4 among those with prolonged glucocorticoid use).

Conclusions

FRAX provides improvement in fracture risk prediction compared with the simplified CAROC tool in individuals referred for osteoporosis screening, supporting the use of FRAX as the international reference tool for fracture risk assessment.
  相似文献   
973.
Odontogenic myxofibroma represents a rare slow‐growing benign neoplasm, which usually occurs in the second and third decades of life and rarely in children or adults over 50 years of age. Myxomas in general represent from 2.3% to 17.7% of all odontogenic tumors, and myxofibromas represent a small number of all myxomas. Limited evidence is present in literature regarding the cytological diagnosis of odontogenic myxoma/myxofibroma. We hereby report the cytomorphological features of a histologically confirmed case of odontogenic myxofibroma and the pitfalls of the cytological diagnosis. A painless jaw swelling in a young boy was aspirated. Scanty mucoid material was obtained. Cytology Smears were moderately cellular and showed a population comprising predominantly of singly scattered plump to fusiform cells with bipolar cytoplasmic processes showing mild to moderate atypia embedded within dense myxoid matrix and another population of cells arranged in clusters. Case was interpreted as low grade mesenchymal tumor. Subsequent biopsy confirmed it as odontogenic myxofibroma arising in a odontogenic keratocyst. Precise interpretation of intraosseous jaw lesions FNAC may not always be possible, but an attempt should be made to broadly classify the lesion as an inflammatory lesion, cystic lesion, giant cell lesion, fibro‐osseous lesion or as an odontogenic tumor. If dual population of odontogenic epithelium and mesenchymal cells embedded in myxoid matrix are identified in such aspirates, a possibility of myxoid odontogenic tumor may be suggested. Triple correlation of cytological, clinical and radiological findings can guide the surgeon for taking appropriate therapeutic decisions. Diagn. Cytopathol. 2016;44:329–333. © 2016 Wiley Periodicals, Inc.  相似文献   
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Context: The unique physiological limitations of the eye have been assigned as reason of low bioavailability by conventional drug delivery systems. There is need of such drug carriers, which ensure improved bioavailability as well as patient compliance upon instillation into the eye.

Objective: The present investigation deals with development of solid lipid nanoparticles (SLNs) containing celecoxib (CXB) for treatment of ophthalmic inflammations.

Materials and methods: The SLNs were formulated by melt-emulsion sonication and low temperature-solidification process and evaluated for particle size, surface morphology, physicochemical properties, percentage drug incorporation efficiency, in vitro drug release, in vitro trans-corneal permeation, in vivo efficacy in ocular inflammation, stability study and gamma scintigraphy study to assess the residence of solid lipid nanoparticles over ocular surfaces.

Results: The SLNs were spherical and the optimized formulation had particle size of 198.77?±?7.5?nm, which is quite suitable for ocular applications. The maximum entrapment efficiency of 92.46?±?0.07% was achieved for formulation SLN 20. The permeation across the cornea was also significantly better than aqueous suspension (8.21?±?0.67 versus 4.61?±?0.71) at p?<?0.05.

Discussion and conclusion: The SLN formulations demonstrated improved performance of entrapped CXB while mitigating the key parameters of ocular inflammation in rabbits. The particulate formulations have exhibited prolonged retention over ocular surfaces as evident from results of gamma scintigraphy using 99mTc labeled SLNs.  相似文献   
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978.
Osteoarthritis (OA) is a major degenerative joint disease characterized by progressive loss of articular cartilage, synovitis, subchondral bone changes, and osteophyte formation. Currently there is no treatment for OA except temporary pain relief and end‐stage joint replacement surgery. We performed a pilot study to determine the effect of kartogenin (KGN, a small molecule) on both cartilage and subchondral bone in a rat model of OA using multimodal imaging techniques. OA was induced in rats (OA and KGN treatment group) by anterior cruciate ligament transection (ACLT) surgery in the right knee joint. Sham surgery was performed on the right knee joint of control group rats. KGN group rats received weekly intra‐articular injection of 125 μM KGN 1 week after surgery until week 12. All rats underwent in vivo magnetic resonance imaging (MRI) at 3, 6, and 12 weeks after surgery. Quantitative MR relaxation measures (T and T2) were determined to evaluate changes in articular cartilage. Cartilage and bone turnover markers (COMP and CTX‐I) were determined at baseline, 3, 6, and 12 weeks. Animals were sacrificed at week 12 and the knee joints were removed for micro‐computed tomography (micro‐CT) and histology. KGN treatment significantly lowered the T and T2 relaxation times indicating decreased cartilage degradation. KGN treatment significantly decreased COMP and CTX‐I levels indicating decreased cartilage and bone turnover rate. KGN treatment also prevented subchondral bone changes in the ACLT rat model of OA. Thus, kartogenin is a potential drug to prevent joint deterioration in post‐traumatic OA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1780–1789, 2016.  相似文献   
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