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Objectives
To examine the potential added value of a simple 5-item questionnaire for sarcopenia screening (SARC-F) to the Fracture Risk Assessment Tool (FRAX) for hip fracture risk prediction, in order to identify at-risk older adults for screening with dual-energy x-ray absorptiometry (DXA).Design
A prospective cohort study.Setting and participants
Two thousand Chinese men and 2000 Chinese women aged 65 years or older were recruited from local communities and were prospectively followed up for about 10 years.Measures
Areal bone mineral density (BMD) of hip and lumbar spine were measured by DXA at baseline. Ten-year FRAX probability of hip fracture was calculated using the baseline risk factors. Information from the baseline questionnaire was extracted to calculate a modified SARC-F score. The independent predictive values of SARC-F and FRAX questionnaire were evaluated using multivariate survival analysis. The added predictive values of SARC-F to FRAX for pre-DXA screening were examined.Results
During the follow-up, 63 (3.2%) men and 69 (3.5%) women had at least 1 incident hip fracture. SARC-F had an independent value of FRAX for hip fracture risk prediction, with an adjusted hazard ratio [95% confidence interval (CI)] of 1.24 (1.02, 1.52) and 1.15 (0.99, 1.13) in men and women, respectively. Compared with using FRAX, using SARC-F in conjunction with FRAX made the sensitivity for prediction rise from 58.7% to 76.2% in men and from 69.6% to 78.3% in women, with a nondecreased area under receiver operating characteristic curve of 0.67. Prescreening using FRAX in conjunction with SARC-F could save more than half of the DXA assessment than with no prescreening.Conclusions/Implications
SARC-F is associated with a modest increase in hip fracture risk, especially in men. Conjoint evaluation for sarcopenia in addition to FRAX screening may help identify older adults at higher risk of hip fracture for more intensive screening and/or preventive interventions. 相似文献Abbreviations
- AR
- androgen receptor
- ATP
- adenosine triphosphate
- CN
- copy number
- CPT1
- carnitine palmitoyltransferase I
- CS
- citrate synthase
- EMT
- epithelial–mesenchymal transition
- ET
- electron transfer‐state
- FABP
- fatty acid‐binding protein
- LD
- lipid droplet
- OA
- oleic acid
- PCa
- prostate cancer
- PPAR
- peroxisome proliferator‐activated receptor
- PPRE
- peroxisome proliferator‐activated receptor response element
- TZD
- thiazolidinediones
Materials and methods: The viability of PC12 cells was measured by using MTT assay. The expressions of tyrosine hydroxylase (TH), thioredoxin-1 (Trx-1), CyclinD1 and Cyclin-dependent kinase5 (Cdk5) were detected by Western Blot.
Results: In present study, we found that morphine increased the cell viability in PC12 cells. 1-methyl-4-phenylpyridi-nium (MPP+) reduced the cell viability and TH expression, which were reversed by morphine. MPP+ decreased the expressions of Trx-1, CyclinD1, Cdk5, which were restored by morphine. Moreover, the role of morphine in restoring the expressions of Trx-1, CyclinD1 and Cdk5 decreased by MPP+ was abolished by LY294002, phosphatidylinositol-3-kinase (PI3K)/Akt inhibitor.
Conclusions: These results suggest that morphine reverses effects induced by MPP þ through activating PI3K/Akt pathway. 相似文献