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51.
Lauren E. Salminen Peter R. Schofield Elizabeth M. Lane Jodi M. Heaps Kerrie D. Pierce Ryan Cabeen David H. Laidlaw Erbil Akbudak Thomas E. Conturo Stephen Correia Robert H. Paul 《Brain imaging and behavior》2013,7(3):274-281
The epsilon 4 (e4) isoform of apolipoprotein E (ApoE) is a known genetic risk factor for suboptimal brain health. Morphometry studies of brains with Alzheimer’s disease have reported significant alterations in temporal lobe brain structure of e4 carriers, yet it remains unclear if the presence of an e4 allele is associated with alterations in the microstructure of white matter fiber bundles in healthy populations. The present study used quantitative tractography based on diffusion tensor imaging (qtDTI) to examine the influence of the e4 allele on temporal lobe fiber bundle lengths (FBLs) in 64 healthy older adults with at least one e4 allele (carriers, N?=?23) versus no e4 allele (non-carriers, N?=?41). Subtests from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were also analyzed to examine memory performance between groups. Analyses revealed shorter FBLs in the left uncinate fasciculus (UF) (p?=?.038) of e4 carriers compared to non-carriers. By contrast, neither FBLs specific to the temporal lobe nor memory performances differed significantly between groups. Increased age correlated significantly with shorter FBL in the temporal lobe and UF, and with decreased performance on tests of memory. This is the first study to utilize qtDTI to examine relationships between FBL and ApoE genotype. Results suggest that FBL in the UF is influenced by the presence of an ApoE e4 allele (ApoE4) in healthy older adults. Temporal lobe FBLs, however, are more vulnerable to aging than the presence of an e4 allele. 相似文献
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Jacob D. Bolzenius David H. Laidlaw Ryan P. Cabeen Thomas E. Conturo Amanda R. McMichael Elizabeth M. Lane Jodi M. Heaps Lauren E. Salminen Laurie M. Baker John Gunstad Robert H. Paul 《Brain imaging and behavior》2013,7(3):300-306
Increased body mass index (BMI) has been linked to various detrimental health outcomes, including cognitive dysfunction. Recent work investigating associations between obesity and the brain has revealed decreased white matter microstructural integrity in individuals with elevated BMI, independent of age or comorbid health conditions. However, the relationship between high BMI and white matter fiber bundle length (FBL), which represents a novel metric of microstructural brain integrity, remains unknown. The present study utilized quantitative tractography based on diffusion tensor imaging (DTI) to investigate the relationship between BMI and FBL in 72 otherwise healthy older adults (24 males, 48 females). All participants were between 51 and 85 years of age (M?=?63.26, SD?=?8.76). Results revealed that elevated BMI was associated with shorter FBL in the temporal lobe, independent of age (p?<?.01). In addition, increased age was associated with shorter frontal, temporal, and whole brain FBL (all p values?<?.01). These findings indicate that, while increased age is an important factor associated with reduced FBL, high BMI is uniquely associated with reduced FBL in the temporal lobe. These data offer evidence for additive adverse effects of high BMI on the brain, especially in areas already vulnerable to aging processes and age-related neurodegenerative diseases. Further research is necessary to determine the physiological mechanisms associated with the shortening of FBL in individuals with high BMI. 相似文献
53.
Laurie M. Baker Leanne M. Williams Mayuresh S. Korgaonkar Ronald A. Cohen Jodi M. Heaps Robert H. Paul 《Brain imaging and behavior》2013,7(2):196-203
Previous studies of early life trauma suggest that in addition to its emotional impact, exposure to early life stress (ELS) is associated with alterations in brain structure. However, little attention has been devoted to the relationship between emotional processing and brain integrity as a function of age of ELS onset. In the present study we examined whether ELS onset in older ages of youth rather than younger ages is associated with smaller limbic and basal ganglia volumes as measured by magnetic resonance imaging (MRI). We hypothesized that later age of manifestation during youth is associated with smaller volumetric morphology in limbic and basal ganglia volumes in adulthood. A total of 173 individuals were divided into three groups based on the age of self-reported ELS. The three groups included individuals only experiencing early childhood ELS (1 month–7 years, n = 38), those only experiencing later childhood ELS (8 years –17 years, n = 59), and those who have not experienced ELS (n = 76). Anterior cingulate cortex (ACC), hippocampus, amygdala, insula and caudate volumes were measured using a T1-weighted MRI. Analyses confirmed that later childhood ELS was associated with volumetric reductions in the ACC and insula volumes, while ELS experienced between the ages of 1 month and 7 years was not associated with lower brain volumes in these regions. The results may reflect the influence of more fully developed emotional processing of ELS on the developing brain and reinforce a body of research implicating both the ACC and insula in neuropsychiatric disorders and emotional regulation. 相似文献
54.
Segal JB 《Journal of general internal medicine》2012,27(Z1):S20-S27
In this chapter of the Evidence-based Practice Centers Methods Guide for Medical Tests, we describe how the decision to use a medical test generates a broad range of outcomes and that each of these outcomes should be considered for inclusion in a systematic review. Awareness of these varied outcomes affects how a decision maker balances the benefits and risks of the test; therefore, a systematic review should present the evidence on these diverse outcomes. The key outcome categories include clinical management outcomes and direct health effects; emotional, social, cognitive, and behavioral responses to testing; legal and ethical outcomes, and costs. We describe the challenges of incorporating these outcomes in a systematic review, suggest a framework for generating potential outcomes for inclusion, and describe the role of stakeholders in choosing the outcomes for study. Finally, we give examples of systematic reviews that either included a range of outcomes or that might have done so. The following are the key messages in this chapter: Consider both the outcomes that are relevant to the process of testing and those that are relevant to the results of the test. Consider inclusion of outcomes in all five domains: clinical management effects, direct test effects; emotional, social, cognitive and behavioral effects; legal and ethical effects, and costs. Consider to which group the outcomes of testing are most relevant. Given resource limitations, prioritize which outcomes to include. This decision depends on the needs of the stakeholder(s), who should be assisted in prioritizing the outcomes for inclusion. 相似文献
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Jonathan M. Mond Phillipa J. Hay Susan J. Paxton Bryan Rodgers Anita Darby Jodi Nillson 《Eating disorders》2013,21(4):267-285
Attitudes and beliefs concerning the nature and treatment of bulimia nervosa (BN) were compared among young adult women at low risk of an eating disorder (n = 332), at high risk (n = 83), or already showing symptoms (n = 94). Participants completed a self-report questionnaire that included a measure of eating disorder symptoms. A vignette of a fictional person suffering from BN was presented, followed by a series of questions addressing the nature and treatment of the problem described. High-risk and symptomatic participants were more likely than low-risk participants to report that they would not approach anyone for advice or help, were they to have BN or a similar problem, because they would not want anyone to know. Symptomatic participants were more likely to believe that someone with BN would be discriminated against, more likely to consider bulimic behaviors to be acceptable, and more likely to view BN as being common among women in the community, than low-risk participants, participants in the high-risk group being intermediate on each of these questions. The findings suggest that the attitudes and beliefs of individuals with eating disorder symptoms differ systematically from those of individuals at high risk, but who do not yet have symptoms, and from those at low risk. They also indicate specific attitudes and beliefs that may need to be addressed in prevention and early intervention programs. The potential benefits of assessing individuals' attitudes and beliefs concerning the nature and treatment of eating-disordered behaviour and tailoring program content accordingly may be worthy of investigation. 相似文献
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Reduction in Overt and Silent Stroke Recurrence Rate Following Cerebral Revascularization Surgery in Children with Sickle Cell Disease and Severe Cerebral Vasculopathy 下载免费PDF全文
60.
ATM,THMS, and RRM1 protein expression in nasopharyngeal carcinomas treated with curative intent 下载免费PDF全文
Jenny Jaeeun Ko MD FRCPC Alexander C. Klimowicz PhD Amanda Jagdis MD Tien Phan MD FRCPC Janessa Laskin MD FRCPC Harold Y. Lau MD FRCPC Jodi E. Siever MSc Stephanie K. Petrillo MSc Thomas A. Thomson MD FRCPC M. Sarah Rose PhD Gwyn Bebb MBMCh PhD FRCPC Anthony M. Magliocco MD FRCPC FCAP Desirée Hao MD FRCPC 《Head & neck》2016,38(Z1):E384-E391