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71.
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Background

As low bone mineral density is a risk factor for fracture in childhood, optimizing age appropriate bone mass is recommended and might lower the impact of bone loss related to age. Consumption of omega-3 polyunsaturated fatty acids (PUFAs), including eicosapentaenoic and docosahexaenoic (DHA) acids have been shown to beneficially modulate bone metabolism. The objective of this study was to determine the incidence of fracture in neonates receiving a fish compared with soybean oil–based intravenous lipid emulsion and evaluate the effect of varying dietary omega-3 PUFA consumption on growing bone in young mice.

Materials and methods

Eligibility criteria for the clinical study included gestational age ≤37 wk and parenteral nutrition–dependence for ≥4 wk. Radiographs were reviewed after lipid initiation to identify radiologic bone fracture. The animal study evaluated female C57/Bl6 mice randomized into one of five groups from age 3–12 wk, at which time femurs were harvested for micro–computed tomography and light microscopy analysis.

Results

A lower incidence of bone fracture was found in neonates maintained on fish compared with soybean oil. In the animal study, findings suggest the DHA diet provides the best protection against trabecular bone loss as evidenced by increased bone volume fraction, increased trabecular number, and decreased trabecular separation on micro–computed tomography. These protective effects appeared to affect the bone microstructure alone.

Conclusions

The lower fracture risk observed in fish oil fed neonates in combination with the protective effects of DHA observed in the femurs of young C57/BL6 mice suggest an important role for omega-3 PUFAs on bone growth.  相似文献   
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选择32例骨母细胞性肿瘤,包括14例良性骨母细胞瘤、2例侵袭性骨母细胞瘤和16例骨母细胞型骨肉瘤,用ABC法作多种抗血清标记(vimentin、S-100、α-AT、lysozyme、Leu-7、K12和CEA)。结果显示:32例肿瘤性骨母细胞vimentin均呈不同程度的阳性反应;在6例骨母细胞型骨肉瘤和1例侵袭性骨母细胞瘤中散在的单个细胞S-100蛋白呈阳性反应,表明肿瘤性的骨母细胞具有软骨分化的潜能124例肿瘤中的多核巨细胞α-AT和15例肿瘤中的多核巨细胞lysozyme均呈不同程度的阳性反应,进一步证实这些细胞可能是组织细胞起源;6例骨母细胞型骨肉瘤和4例良性骨母细胞瘤中的骨样基质Leu-7呈阳性反应。  相似文献   
74.
ContextIn patients with prostate cancer, bone health is compromised by advanced age at diagnosis, androgen suppression treatments and the developmentofbone metastases. In this paper the medical literature is reviewed in order to update the state of the art on their incidence, prevention and management.Evidence acquisitionA literature review about bone involvement in patients with prostate cancer in different clinical settings is performed.Synthesis of the evidenceDecreased bone mineral density is higher in patients diagnosed of prostate cancer before starting treatment than in healthy men with the same age. During the first year of treatment, a severe loss bone density is reported due to androgen suppression therapy. From then on, loss bone density seems to slow down, persisting at long-term. It is important to know the starting point and the dynamics of loss bone in order to prevent its progression. The skeletal events have an important impact on quality of life in patients with prostate cancer. Both Denosumab and Zoledronic Acid have proven effective in reducing loss bone.ConclusionsThe prevention and management of bone involvement in patients with prostate cancer is critical to quality of life in these patients and requires an individualized approach. Before starting a prolonged androgen deprivation, baseline risk of fracture should be evaluated in order to adopt the proper protective measures. In patients with metastases, early treatments reducing the risk of bone events should be taken into account.  相似文献   
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Background

Zoledronic acid (ZOL) is a standard therapy for the prevention of skeletal-related events (SREs) in patients with castration-resistant prostate cancer (CRPC). Although prostate-specific antigen (PSA) is an established marker for monitoring prostate cancer patients, correlations between PSA and disease outcomes during ZOL therapy are unclear.

Objective

To evaluate the relationships among PSA kinetics, bone-directed therapy with ZOL, and clinical outcomes in men with bone metastases from CRPC using a ZOL phase 3 trial database.

Design, setting, and participants

Exploratory analyses from a phase 3 trial in men with bone metastases from CRPC (n = 643) randomized to ZOL or placebo every 3 wk.

Outcome measurements and statistical analysis

PSA levels during the first 3 mo of the study were evaluated in linear and logarithmic (log) models stratified using prognostic factors established in a ZOL phase 3 trial and a CRPC nomogram. Relative risks of SREs, bone disease progression (BDP), and death were calculated per 1 log (nanograms per milliliter) PSA increase. Baseline PSA models used the study median (PSA: 77.3 ng/ml) as the high/low cut-off point.

Results and limitations

A total of 202 placebo- and 434 ZOL-treated patients were assessable. In both groups, PSA increases correlated with significantly increased risks of death, BDP, and first SRE. In the placebo and ZOL groups, associated increases in risk per 1 log (nanograms per milliliter) PSA increase were 29% (p < 0.0001) and 10% (p < 0.0074), respectively, for BDP, and 24% (p = 0.0010) and 13% (p = 0.0079), respectively, for first SRE. Limitations include the retrospective nature of these analyses and the potential confounding effects of concurrent antineoplastic therapies.

Conclusions

PSA is an important prognostic tool for survival in patients with bone metastases from CRPC, and these analyses show that PSA is also prognostic for BDP and SREs regardless of bone-targeted therapy.  相似文献   
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