391 research outputs found
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The effect of prior caffeine consumption on neuropsychological test performance: a placebo-controlled study
YesBackground: The aim of this study was to investigate whether the prior consumption of 200mg of pure caffeine affected neuropsychological test scores in a group of elderly participants aged over 60 years. Method: Using a double blind placebo vs. caffeine design, participants were randomly assigned to receive 200mg of caffeine or placebo. A neuropsychological assessment testing the domains of general cognitive function, processing speed, semantic memory, episodic memory, executive function, working memory and short-term memory was carried out. Results: Significant interaction effects between age, caffeine and scores of executive function and processing speed were found; participants who had received caffeine showed a decline in performance with increasing age. This effect was not seen for participants who received placebo. Conclusion: The results highlight the need to consider and control prior caffeine consumption when scoring neuropsychological assessments in the elderly which is important for accuracy of diagnosis and corresponding normative data
Time of day and caffeine influence some neuropsychological tests in the elderly
YesWe report that performance on neuropsychological tests used in the diagnosis of dementia can be influenced by external factors such as time of day (TOD) and caffeine. This study investigates TOD effects on cognitive performance in the elderly. The optimal TOD at which an individual is at their maximal arousal alters with age and in the elderly typically occurs in the morning. Neuropsychological test scores from healthy elderly participants were analysed to determine whether TOD affected performance. Interactions between caffeine and TOD were also investigated. Across two data sets that were analysed, significant TOD effects were noted for Pattern Comparison Speed (PCS), Letter Comparison Speed (LCS), Trail Making Test Part A, Mini Mental State Examination (MMSE) and the Graded Naming Test (GNT), revealing a decline in test scores as TOD increases. Significant interactions between TOD, age and the PCS, LCS and Trail Making part A were noted in data set one. In data set two, where caffeine intake had been controlled for, significant interactions between caffeine, TOD and scores on the MMSE and GNT were found. The TOD and caffeine effects highlight the need to control for these external factors when scoring the assessments. This conclusion has implications for the clinical procedure of diagnosis and treatment of dementia and Alzheimer’s
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Factors affecting neuropsychological testing in the elderly and the use of a newly developed virtual reality test. Implications for the accurate and early diagnosis of Alzheimer's disease.
Neuropsychological testing is one method used in the diagnosis of Alzheimer’s disease and other cognitive disorders. However, the testing process may be affected by subtle external factors which if not controlled for may have the ability to affect the scores obtained. The primary aim of this thesis was to investigate the effects of some of these external factors, namely caffeine, non-oily fish consumption and time of day. A secondary aim was to evaluate the use of a novel virtual assessment as a possible tool for the early detection of AD. Healthy elderly participants over the age of sixty with no existing cognitive impairment or neurological condition were recruited to take part. For each external factor investigated participants were required to undertake a cognitive assessment. The results demonstrated that subtle external factors present during a typical testing session have the ability to significantly affect the scores obtained. Scores on one part of the virtual test correlated with existing tests used for the early detection of cognitive impairment and were significantly lower in participants classified as mildly impaired. With further modification this test has the potential to be used as an early detection tool. The results have implications for the interpretation of neuropsychological test scores which may be considered when classifying participants, determining treatment interventions, selecting participants for research and making a diagnosis. These findings have important considerations for psychological and cognitive research that investigates human brain function
Investigating the time elapsed since the last food item was consumed as a factor affecting cognitive performance in young adults
YesCognitive ability is used in numerous everyday situations (for example, in the classroom, workplace and home) and can be measured using cognitive tests designed to target specific cognitive domains. Cognition can be influenced by external factors (for example, age, education, caffeine intake and time of day) which if not controlled for or noted could influence performance. Prior food intake has not received a direct focus in the cognition literature, and therefore, this study aims to investigate the time elapsed since the last food item was consumed as a factor which may affect cognitive performance. Fifty-two healthy adults with no reported cognitive impairment or diagnosis of any eating or metabolic disorder took part in the study. Participants completed a self-rated hunger scale and stated the time that they last consumed a food item. The time of day that the assessments were completed was also noted. All participants completed a brief cognitive battery consisting of a semantic recall assessment, digit span and parts A and B of the Trail Making Test. Results revealed a significant main effect of minutes since the last food item was consumed on semantic recall and both Trails A and B whereby performance was significantly worse as the time since the last food item was consumed increased. These results suggest that information about when the participant consumed food prior to assessment should be gathered to check for any such effects. This could have implications for cognitive performance in educational settings and clinical environments, where scores often determine academic progression and further interventions
Charter School Demand and Effectiveness: A Boston Update
This report begins with a focus on applications to charter schools. While much attention has been focused on charter school waitlists, waitlist data can be misleading. It includes duplicates, but also includes waitlists that have been rolled over from year to year and might be an unrealistic measure of demand. Instead, the authors investigate three factors related to demand: the yearly percentage of each middle school and high school class that applies to a charter in our lottery sample; the percentage of applicants that receive an offer from a charter school; and where students ultimately attend. This report also examines the demographic makeup of charter school enrollees and compare it to BPS. The next section follows the path of charter school students and report their performance in charters using the evidence from the lotteries. The lottery sample now covers many more charter schools. The 2009 report included findings from eight schools. This report includes MCAS results through 2012 from 12 schools and many more cohorts from the original schools, with additional newly opened schools contributing to the demand analysis. In addition to updating the test score results from the 2009 report, this report breaks down the test score effects by student subgroups. Trends are investigated over time in charter performance and by school groups. Finally, this report gives results using statistical controls, which allow the authros to estimate effects for attending charter schools that do not have sufficient lottery records for the more rigorous lottery based analysis. The lottery sample now contains almost all Boston charter schools with entry grades at middle or high school
Computational identification of hepatitis C virus associated microRNA-mRNA regulatory modules in human livers
<p>Abstract</p> <p>Background</p> <p>Hepatitis C virus (HCV) is a major cause of chronic liver disease by infecting over 170 million people worldwide. Recent studies have shown that microRNAs (miRNAs), a class of small non-coding regulatory RNAs, are involved in the regulation of HCV infection, but their functions have not been systematically studied. We propose an integrative strategy for identifying the miRNA-mRNA regulatory modules that are associated with HCV infection. This strategy combines paired expression profiles of miRNAs and mRNAs and computational target predictions. A miRNA-mRNA regulatory module consists of a set of miRNAs and their targets, in which the miRNAs are predicted to coordinately regulate the level of the target mRNA.</p> <p>Results</p> <p>We simultaneously profiled the expression of cellular miRNAs and mRNAs across 30 HCV positive or negative human liver biopsy samples using microarray technology. We constructed a miRNA-mRNA regulatory network, and using a graph theoretical approach, identified 38 miRNA-mRNA regulatory modules in the network that were associated with HCV infection. We evaluated the direct miRNA regulation of the mRNA levels of targets in regulatory modules using previously published miRNA transfection data. We analyzed the functional roles of individual modules at the systems level by integrating a large-scale protein interaction network. We found that various biological processes, including some HCV infection related canonical pathways, were regulated at the miRNA level during HCV infection.</p> <p>Conclusion</p> <p>Our regulatory modules provide a framework for future experimental analyses. This report demonstrates the utility of our approach to obtain new insights into post-transcriptional gene regulation at the miRNA level in complex human diseases.</p
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Dying 2 Talk: Generating a more compassion community for young people
YesPeople in the Global North often have a problem talking about — and processing — the inevitability of death. This can be because death and care of the dying has been professionalised, with encounters of death within our families and communities no longer being ‘normal and routine’ (Kellehear 2005). Young people are particularly excluded from these conversations, with implications for future mental health and wellbeing (Ainsley-Green 2017). Working in Wolverhampton and Bradford, the Dying 2 Talk (D2T) project aimed to build young people’s future resilience around this challenging topic. We recruited over 20 young people as project ambassadors to co-produce resources that would encourage talk about death, dying and bereavement. The resources were used as the basis of ‘Festivals of the Dead’ which were taken to schools to engage wider audiences of young people (aged 11 +). The project aimed to use alternative ‘ways in’ to open discussion, beginning with archaeology, and ultimately using gaming, dance, creative writing and other creative outputs to facilitate discussion, encourage compassionate relationships and build resilience. The resources succeeded in engaging young people from ages 11–19 years, facilitating a comfortable and supportive environment for these vital conversations. Project evaluations and observations revealed that the Festivals, and the activities co-created by the young ambassadors helped to facilitate spontaneous conversations about death, dying and bereavement amongst young people by providing a comfortable and supportive environment. The project was funded by the Arts and Humanities Research Council (AH/V008609/1), building on a pilot project funded by the Higher Education Innovation Fund at the University of Bradford.The project was funded by the Arts and Humanities Research Council (AH/V008609/1), building on a pilot project funded by the Higher Education Innovation Fund at the University of Bradford
Should the grading of colorectal adenocarcinoma include microsatellite instability status?
Adenocarcinomas of the colon and rectum are graded using a 2-tiered system into histologic low-grade and high-grade tumors based on the proportion of gland formation. The current grading system does not apply to subtypes of carcinomas associated with a high frequency of microsatellite instability (MSI), such as mucinous and medullary carcinomas. We investigated the combined effect of histologic grade and MSI status on survival for 738 patients with colorectal carcinoma (48% female; mean age at diagnosis 68.2 years). The proportion of high-grade adenocarcinoma was 18%. MSI was observed in 59 adenocarcinomas (9%), with higher frequency in high-grade tumors compared with low-grade tumors (20% versus 6%; P < .001). Using Cox regression models, adjusting for sex and age at diagnosis and stratifying by the American Joint Committee on Cancer stage, microsatellite stable (MSS) high-grade tumors were associated with increased hazard of all-cause and colorectal cancer specific mortality: hazard ratio 2.09 (95% confidence interval [CI], 1.58-2.77) and 2.54 (95% CI, 1.86-3.47), respectively, both P < .001. A new grading system separating adenocarcinoma into low grade (all histologic low grade and MSI high grade) and high grade (MSS histologic high grade) gave a lower Akaike information criterion value when compared with the current grading system and thus represented a better model fit to stratify patients according to survival. We found that patients with a high-grade adenocarcinoma had significantly shorter survival than patients with low-grade adenocarcinoma only if the tumor was MSS, suggesting that the grading of colorectal adenocarcinoma with high-grade histologic features should be made according to the MSI status of the tumor. (C) 2014 Elsevier Inc. All rights reserved
Lifetime alcohol intake is associated with an increased risk of KRAS+ and BRAF-/KRAS- but not BRAF+ colorectal cancer.
Ethanol in alcoholic beverages is a causative agent for colorectal cancer. Colorectal cancer is a biologically heterogeneous disease, and molecular subtypes defined by the presence of somatic mutations in BRAF and KRAS are known to exist. We examined associations between lifetime alcohol intake and molecular and anatomic subtypes of colorectal cancer. We calculated usual alcohol intake for 10-year periods from age 20 using recalled frequency and quantity of beverage-specific consumption for 38,149 participants aged 40-69 years from the Melbourne Collaborative Cohort Study. Cox regression was performed to derive hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between lifetime alcohol intake and colorectal cancer risk. Heterogeneity in the HRs across subtypes of colorectal cancer was assessed. A positive dose-dependent association between lifetime alcohol intake and overall colorectal cancer risk (mean follow-up = 14.6 years; n = 596 colon and n = 326 rectal cancer) was observed (HR = 1.08, 95% CI: 1.04-1.12 per 10 g/day increment). The risk was greater for rectal than colon cancer (phomogeneity  = 0.02). Alcohol intake was associated with increased risks of KRAS+ (HR = 1.07, 95% CI: 1.00-1.15) and BRAF-/KRAS- (HR = 1.05, 95% CI: 1.00-1.11) but not BRAF+ tumors (HR = 0.89, 95% CI: 0.78-1.01; phomogeneity  = 0.01). Alcohol intake is associated with an increased risk of KRAS+ and BRAF-/KRAS- tumors originating via specific molecular pathways including the traditional adenoma-carcinoma pathway but not with BRAF+ tumors originating via the serrated pathway. Therefore, limiting alcohol intake from a young age might reduce colorectal cancer originating via the traditional adenoma-carcinoma pathway
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