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The purpose of this study was to determine the individual and combined effects on periprosthetic cancellous bone of intermittent parathyroid hormone administration (iPTH) and mechanical loading at the cellular, molecular, and tissue levels. Porous titanium implants were inserted bilaterally on the cancellous bone of adult rabbits beneath a loading device attached to the distal lateral femur. The left femur received a sham loading device. The right femur was loaded daily, and half of the rabbits received daily PTH. Periprosthetic bone was evaluated up to 28 days for gene expression, histology, and µCT analysis. Loading and iPTH increased bone mass by a combination of two mechanisms: (1) Altering cell populations in a pro‐osteoblastic/anti‐adipocytic direction, and (2) controlling bone turnover by modulating the RANKL‐OPG ratio. At the tissue level, BV/TV increased with both loading (+53%, p < 0.05) and iPTH (+54%, p < 0.05). Combined treatment showed only small additional effects at the cellular and molecular levels that corresponded to a small additive effect on bone volume (+13% compared to iPTH alone, p > 0.05). This study suggests that iPTH and loading are potential therapies for enhancing periprosthetic bone formation. The elucidation of the cellular and molecular response may help further enhance the combined therapy and related targeted treatment strategies. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:163–173, 2015.
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Calcium supplementation, particularly with vitamin D, has been an approved public health intervention to reduce fracture risk. Enthusiasm for this intervention has been mitigated by meta‐analyses suggesting that calcium supplementation with or without vitamin D increases myocardial infarction (MI) risk; however, concern has been raised over the design of these meta‐analyses. We, therefore, undertook a meta‐analysis of randomized controlled trials with placebo or no‐treatment control groups to determine if these supplements increase all‐cause mortality and coronary heart disease (CHD) risk including MI, angina pectoris and acute coronary syndrome, and chronic CHD verified by clinical review, hospital record, or death certificate in elderly women. The Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were searched from January 1, 1966, to May 24, 2013, for potentially eligible studies, reference lists were checked, and trial investigators were contacted where additional unpublished data were required. The search yielded 661 potentially eligible reports of which 18 met the inclusion criteria and contributed information on 63,563 participants with 3390 CHD events and 4157 deaths. Two authors extracted the data independently with trial data combined using random‐effects meta‐analysis to calculate the relative risk (RR). Five trials contributed CHD events with pooled relative RR of 1.02 (95% confidence interval [CI], 0.96–1.09; p = 0.51). Seventeen trials contributed all‐cause mortality data with pooled RR of 0.96 (95% CI, 0.91–1.02; p = 0.18). Heterogeneity among the trials was low for both primary outcomes (I2 = 0%). For secondary outcomes, the RR for MI was 1.08 (95% CI, 0.92–1.26; p = 0.32), angina pectoris and acute coronary syndrome 1.09 (95% CI, 0.95–1.24; p = 0.22) and chronic CHD 0.92 (95% CI, 0.73–1.15; p = 0.46). In conclusion, current evidence does not support the hypothesis that calcium supplementation with or without vitamin D increases coronary heart disease or all‐cause mortality risk in elderly women. © 2014 American Society for Bone and Mineral Research.  相似文献   
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Purpose

To examine cross-sectional associations between food insecurity and 12-month eating disorders, mood disorders, and anxiety disorders among U.S. adults.

Methods

This study used data collected between 2001 and 2003 from 2914 participants in the National Comorbidity Survey-Replication, a nationally representative sample of U.S. adults (mean age = 44.9 years; 53.4% female). Twelve-month food insecurity was assessed with a modified version of the Short Form U.S. Household Food Security Scale. Twelve-month DSM-IV diagnoses of mental disorders were based on the World Health Organization Composite International Diagnostic Interview. Modified Poisson regression models were conducted, adjusting for age, sex, race/ethnicity, education, and income-to-poverty ratio.

Results

Food insecurity was experienced by 11.1% of participants. Food insecurity was associated with greater prevalence of bulimic-spectrum eating disorders (prevalence ratio [PR] = 3.81; 95% confidence interval [CI] 2.26–6.42), mood disorders (PR = 2.53; 95% CI 1.96–3.29), and anxiety disorders (PR = 1.69; 95% CI 1.39–2.07).

Conclusion

Results indicate that food insecurity is associated with a range of internalizing mental disorders, though these findings should be confirmed with contemporary data to reflect DSM-5 diagnostic updates and the economic effects of the COVID-19 pandemic. Findings from this study emphasize the need to expand food insecurity interventions and improve access to mental health services for food-insecure populations.

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Cardiac allograft vasculopathy (CAV) limits long-term survival after heart transplantation. Non-invasive evaluation is challenging, and currently, there is no validated biomarker for CAV diagnosis or prognostication. To identify potential candidate CAV biomarkers, we utilized the Slow Off-rate Modified Aptamer (SOMAscan) assay, which evaluates over 1000 serum proteins, including many relevant to biological pathways in CAV. We evaluated three heart transplant patient groups according to angiographic ISHLT CAV grade: CAV1-2 (mild-moderate CAV), CAV3 (severe CAV), and CAV0 (normal control). SOMAscan assays were performed and proteins quantitated. Comparisons of proteins between study groups were performed using one-way ANOVA (false discovery rate q-value < 0.10). Thirty-one patients (12 mild-moderate CAV, 9 severe CAV, 10 controls) were included: 81% male, median age 57 years and median 1.1 years post-transplant. Compared to controls, patients with mild-moderate CAV had similar characteristics, while patients with severe CAV had longer time from transplant and increased allosensitization. Statistical/bioinformatics analysis identified 14 novel biomarkers for CAV, including 4 specific for mild-moderate CAV. These proteins demonstrated important actions including apoptosis, inflammation, and platelet/coagulation activation. Upon preliminary receiver operating characteristics curve analysis, our protein biomarkers showed moderate-to-high discriminative ability for CAV (area under curve: 0.72 to 0.94). These candidate biomarkers are being validated in prospective studies.  相似文献   
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