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Laura Hocum Stone Tammy A. Butterick Cayla Duffy Corey Swingen Herbert B. Ward Rosemary F. Kelly Edward O. McFalls 《Journal of cardiovascular translational research》2016,9(4):368-373
There is conflicting clinical evidence whether administration of coenzyme Q10 (CoQ10) improves function following coronary artery bypass graft surgery (CABG). Using a swine model of hibernating myocardium, we tested whether daily CoQ10 would improve contractile function by MRI at 4-week post-CABG. Twelve pigs underwent a thoracotomy and had a constrictor placed on the left anterior descending (LAD). At 12 weeks, they underwent off-pump bypass and received daily dietary supplements of either CoQ10 (10 mg/kg/day) or placebo. At 4-week post-CABG, circumferential strain measurements in the hibernating LAD region from placebo and CoQ10 groups were not different and increased to a similar extent with dobutamine (?14.7?±?0.6 versus ?14.8?±?0.1, respectively (NS)). Post-sacrifice, oxidant stress markers were obtained in the mitochondrial isolates and protein carbonyl in the placebo, and CoQ10 groups were 6.14?±?0.36 and 5.05?±?0.32 nmol/mg, respectively (NS). In summary, CoQ10 did not improve contractile reserve or reduce oxidant stress at 4-week post-CABG. 相似文献
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Rebecca Byram Robert A. Gaultney Angela M. Floden Christopher Hellekson Brandee L. Stone Amy Bowman Brian Stevenson Barbara J. B. Johnson Catherine A. Brissette 《Infection and immunity》2015,83(9):3675-3683
The Lyme disease spirochete, Borrelia burgdorferi, expresses RevA and numerous outer surface lipoproteins during mammalian infection. As an adhesin that promotes bacterial interaction with fibronectin, RevA is poised to interact with the extracellular matrix of the host. To further define the role(s) of RevA during mammalian infection, we created a mutant that is unable to produce RevA. The mutant was still infectious to mice, although it was significantly less well able to infect cardiac tissues. Complementation of the mutant with a wild-type revA gene restored heart infectivity to wild-type levels. Additionally, revA mutants led to increased evidence of arthritis, with increased fibrotic collagen deposition in tibiotarsal joints. The mutants also induced increased levels of the chemokine CCL2, a monocyte chemoattractant, in serum, and this increase was abolished in the complemented strain. Therefore, while revA is not absolutely essential for infection, deletion of revA had distinct effects on dissemination, arthritis severity, and host response. 相似文献
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Tuong L. Nguyen Shuai Li Gillian S. Dite Ye K. Aung Christopher F. Evans Ho N. Trinh Laura Baglietto Jennifer Stone Yun-Mi Song Joohon Sung Dallas R. English Mark A. Jenkins Pierre-Antoine Dugué Roger L. Milne Melissa C. Southey Graham G. Giles Malcolm C. Pike John L. Hopper 《International journal of cancer. Journal international du cancer》2020,147(2):375-382
Interval breast cancers (those diagnosed between recommended mammography screens) generally have poorer outcomes and are more common among women with dense breasts. We aimed to develop a risk model for interval breast cancer. We conducted a nested case–control study within the Melbourne Collaborative Cohort Study involving 168 interval breast cancer patients and 498 matched control subjects. We measured breast density using the CUMULUS software. We recorded first-degree family history by questionnaire, measured body mass index (BMI) and calculated age-adjusted breast tissue aging, a novel measure of exposure to estrogen and progesterone based on the Pike model. We fitted conditional logistic regression to estimate odds ratio (OR) or odds ratio per adjusted standard deviation (OPERA) and calculated the area under the receiver operating characteristic curve (AUC). The stronger risk associations were for unadjusted percent breast density (OPERA = 1.99; AUC = 0.66), more so after adjusting for age and BMI (OPERA = 2.26; AUC = 0.70), and for family history (OR = 2.70; AUC = 0.56). When the latter two factors and their multiplicative interactions with age-adjusted breast tissue aging (p = 0.01 and 0.02, respectively) were fitted, the AUC was 0.73 (95% CI 0.69–0.77), equivalent to a ninefold interquartile risk ratio. In summary, compared with using dense breasts alone, risk discrimination for interval breast cancers could be doubled by instead using breast density, BMI, family history and hormonal exposure. This would also give women with dense breasts, and their physicians, more information about the major consequence of having dense breasts—an increased risk of developing an interval breast cancer. 相似文献
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Paula J. Fite Rebecca Griffith Elizabeth C. Tampke Katie J. Stone Vishnupriya Srivastava 《Journal of community psychology》2020,48(3):932-944
There is growing evidence indicating that a lack of perceived containment, or youth's beliefs about whether adults can control their behavior, is associated with problem behavior. However, little research has examined factors that may contribute to perceived containment, which would be helpful in further tailoring prevention and intervention efforts for problem behavior. The current study evaluated associations between callous-unemotional (C/U) traits, peer delinquency, neighborhood problems, and perceived containment. Associations were examined using a sample of detained youth. Findings indicated that while all three factors were correlated with perceived containment, only C/U traits (particularly the callousness and uncaring subscales) and peer delinquency were uniquely associated with perceived containment. Further, C/U traits did not moderate the links between peer delinquency or neighborhood problems and perceived containment. This study supports the influence of both individual and contextual factors on perceived containment, suggesting multiple factors to target for prevention and intervention. 相似文献
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Yan Sun PhD Sameer C. Dhamne MS Alejandro Carretero-Guillén PhD Ricardo Salvador PhD Marti C. Goldenberg BS Brianna R. Godlewski BS Alvaro Pascual-Leone MD PhD Joseph R. Madsen MD Scellig S. D. Stone MD PhD Giulio Ruffini PhD Javier Márquez-Ruiz PhD Alexander Rotenberg MD PhD 《Annals of neurology》2020,88(3):489-502