48 research outputs found

    Effective Practices in Science Instruction in an All Girls School

    Get PDF
    Girls can be successful in science education depending on their learning environment. This paper studies factors such as curriculum and instructional strategies that facilitate student success in learning science. The problem is that as girls get older, they shy away from science instruction. They allow boys to monopolize the science activities, and they appear to lose interest in science. Their grades slip, and they tend not to pursue science in higher education or in their career. The purpose of this research is to explore factors that can lead to girls’ success in learning science. Teachers were interviewed at a school site and asked questions about their strategies in teaching science and their perceptions of girls in science at this school

    Guidelines For The Standardization Of Preanalytic Variables For Blood-based Biomarker Studies In Alzheimer\u27s Disease Research

    Get PDF
    The lack of readily available biomarkers is a significant hindrance toward progressing to effective therapeutic and preventative strategies for Alzheimer\u27s disease (AD). Blood-based biomarkers have potential to overcome access and cost barriers and greatly facilitate advanced neuroimaging and cerebrospinal fluid biomarker approaches. Despite the fact that preanalytical processing is the largest source of variability in laboratory testing, there are no currently available standardized preanalytical guidelines. The current international working group provides the initial starting point for such guidelines for standardized operating procedures (SOPs). It is anticipated that these guidelines will be updated as additional research findings become available. The statement provides (1) a synopsis of selected preanalytical methods utilized in many international AD cohort studies, (2) initial draft guidelines/SOPs for preanalytical methods, and (3) a list of required methodological information and protocols to be made available for publications in the field to foster cross-validation across cohorts and laboratorie

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

    Get PDF
    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

    Putting the Alzheimer's cognitive test to the test II:Rasch Measurement Theory

    No full text
    BACKGROUND: The Alzheimer's Disease Assessment Scale-Cognitive Behavior section (ADAS-Cog) is the most widely used measure of cognitive performance in AD clinical trials. This key role has rightly brought its performance under increased scrutiny with recent research using traditional psychometric methods, questioning the ADAS-Cog's ability to adequately measure early-stage disease. However, given the limitations of traditional psychometric approaches, herein we use the more sophisticated Rasch Measurement Theory (RMT) methods to fully examine the strengths and weaknesses of the ADAS-Cog, and identify potential paths toward its improvement.METHODS: We analyzed AD Neuroimaging Initiative (ADNI) ADAS-Cog data (675 measurements across four time-points over 2 years) from the AD participants. RMT analysis was undertaken to examine three broad areas: adequacy of scale-to-sample targeting; degree to which, taken together, the ADAS-Cog items adequately perform as a measuring instrument; and how well the scale measured the subjects in the current sample.RESULTS: The 11 ADAS-Cog components mapped-out a measurement continuum, worked together adequately, and were stable across different time-points and samples. However, the scale did not prove to be a good match to the patient sample supporting previous research. RMT analysis also identified problematic "gaps" and "bunching" of the components across the continuum.CONCLUSION: Although the ADAS-Cog has the building blocks of a good measurement instrument, this sophisticated analysis confirms limitations with potentially serious implications for clinical trials. Importantly, and unlike traditional psychometric methods, our RMT analysis has provided important clues aimed at solving the measurement problems of the ADAS-Cog.</p

    Putting the Alzheimer's cognitive test to the test I: Traditional psychometric methods

    Get PDF
    Background: The Alzheimer’s Disease Assessment Scale—Cognitive Behavior section (ADAS-Cog) is the most commonly used cognitive test in AD clinical trials. However, there are concerns about its use in early-stage disease. Herein we examine those concerns using traditional psychometric methods. Methods: We analyzed ADAS-Cog data (n 5 675) based on six psychometric properties: data completeness; scaling assumptions; targeting; reliability; validity; and responsiveness. Results: At the scale-level, criteria tested for data completeness, scaling assumptions (item total correlations 0.33–0.59), targeting (no floor/ceiling effects), reliability (Cronbach’s a 5 0.74), and validity (correlation with MMSE 5 20.70) were satisfied. Responsiveness (baseline to 12 months; n 5 145) was moderate to high (effect size 5 20.73). However, 8 of 11 ADAS-Cog components had substantial ceiling effects (range 32%–83%), and decreased responsiveness associated with low to moderate effect sizes (0.14–0.65). Conclusion: In our study, many patients with AD found large portions of the ADAS-Cog too easy. Future research should consider modifying the ADAS-Cog or developing a new test. Ó 2013 The Alzheimer’s Association. All rights reserved

    Establishing the psychometric underpinning of cognition measures for clinical trials of Alzheimer's disease and its precursors:a new approach

    No full text
    The Alzheimer's disease (AD) Cognitive Behavior Section (ADAS-Cog) is the most commonly used cognitive test in clinical trials of AD. Recent trials have focused on people earlier in the course of disease; however, there are concerns about using the ADAS-Cog at this crucial stage. Using data from the Alzheimer's disease Neuroimaging Initiative study, we used a range of traditional psychometric tests to evaluate those concerns. This issue of Alzheimer's &amp; Dementia includes two articles that evaluate the ADAS-Cog. These articles report evaluations using two psychometric approaches: traditional methods and new methods. In this review, we provide accompanying background information to this program of research.</p

    Outcomes Assessment in Clinical Trials of Alzheimer's Disease and its Precursors: Readying for Short-term and Long-term Clinical Trial Needs

    No full text
    An evolving paradigm shift in the diagnostic conceptualization of Alzheimer's disease is reflected in its recently updated diagnostic criteria from the National Institute on Aging-Alzheimer's Association and the International Working Group. Additionally, it is reflected in the increased focus in this field on conducting prevention trials in addition to improving cognition and function in people with dementia. These developments are making key contributions towards defining new regulatory thinking around Alzheimer's disease treatment earlier in the disease continuum. As a result, the field as a whole is now concentrated on exploring the next-generation of cognitive and functional outcome measures that will support clinical trials focused on treating the slow slide into cognitive and functional impairment. With this backdrop, the International Society for CNS Clinical Trials and Methodology convened semi-annual working group meetings which began in spring of 2012 to address methodological issues in this area. This report presents the most critical issues around primary outcome assessments in Alzheimer's disease clinical trials, and summarizes the presentations, discussions, and recommendations of those meetings, within the context of the evolving landscape of Alzheimer's disease clinical trials
    corecore