1,465 research outputs found

    Impaired interferon-γ responses, increased interleukin-17 expression, and a tumor necrosis factor–α transcriptional program in invasive aspergillosis

    Get PDF
    This article is available open access through the publisher’s website. Copyright @ 2009 Oxford University Press.Background - Invasive aspergillosis (IA) is the most common cause of death associated with fungal infection in the developed world. Historically, susceptibility to IA has been associated with prolonged neutropenia; however, IA has now become a major problem in patients on calcineurin inhibitors and allogenic hematopoetic stem cell transplant patients following engraftment. These observations suggest complex cellular mechanisms govern immunity to IA. Methods - To characterize the key early events that govern outcome from infection with Aspergillus fumigatus we performed a comparative immunochip microarray analysis of the pulmonary transcriptional response to IA between cyclophosphamide-treated mice and immunocompetent mice at 24 h after infection. Results - We demonstrate that death due to infection is associated with a failure to generate an incremental interferon-γ response, increased levels of interleukin-5 and interleukin-17a transcript, coordinated expression of a network of tumor necrosis factor–α-related genes, and increased levels of tumor necrosis factor–α. In contrast, clearance of infection is associated with increased expression of a number genes encoding proteins involved in innate pathogen clearance, as well as apoptosis and control of inflammation. Conclusion - This first organ-level immune response transcriptional analysis for IA has enabled us to gain new insights into the mechanisms that govern fungal immunity in the lung.The BBSRC, CGD Research Trust, and the MRC

    Q methodology and a Delphi poll: a useful approach to researching a narrative approach to therapy

    Get PDF
    Q methodology and a Delphi poll combined qualitative and quantitative methods to explore definitions of White and Epston's (1990) narrative approach to therapy among a group of UK practitioners. A Delphi poll was used to generate statements about narrative therapy. The piloting of statements by the Delphi panel identified agreement about theoretical ideas underpinning narrative therapy and certain key practices. A wider group of practitioners ranked the statements in a Q sort and made qualitative comments about their sorting. Quantitative methods (principal components analysis) were used to extract eight accounts of narrative therapy, five of which are qualitatively analysed in this paper. Agreement and differences were identified across a range of issues, including the social construction of narratives, privileging a political stance or narrative techniques and the relationship with other therapies, specifically systemic psychotherapy. Q methodology, combined with the Delphi poll, was a unique and innovative feature of this study

    Opinion leaders and changes over time: a survey

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Opinion leaders represent one way to disseminate new knowledge and influence the practice behaviors of physicians. This study explored the stability of opinion leaders over time, whether opinion leaders were polymorphic (<it>i.e.</it>, influencing multiple practice areas) or monomorphic (<it>i.e.</it>, influencing one practice area), and reach of opinion leaders in their local network.</p> <p>Methods</p> <p>We surveyed surgeons and pathologists in Ontario to identify opinion leaders for colorectal cancer in 2003 and 2005 and to identify opinion leaders for breast cancer in 2005. We explored whether opinion leaders for colorectal cancer identified in 2003 were re-identified in 2005. We examined whether opinion leaders were considered polymorphic (nominated in 2005 as opinion leaders for both colorectal and breast cancer) or monomorphic (nominated in 2005 for only one condition). Social-network mapping was used to identify the number of local colleagues identifying opinion leaders.</p> <p>Results</p> <p>Response rates for surgeons were 41% (2003) and 40% (2005); response rates for pathologists were 42% (2003) and 37% (2005). Four (25%) of the surgical opinion leaders identified in 2003 for colorectal cancer were re-identified in 2005. No pathology opinion leaders for colorectal cancer were identified in both 2003 and 2005. Only 29% of surgical opinion leaders and 17% of pathology opinion leaders identified in the 2005 survey were considered influential for both colorectal cancer and breast cancer. Social-network mapping revealed that only a limited number of general surgeons (12%) or pathologists (7%) were connected to the social networks of identified opinion leaders.</p> <p>Conclusions</p> <p>Opinion leaders identified in this study were not stable over a two-year time period and generally appear to be monomorphic, with clearly demarcated areas of expertise and limited spheres of influence. These findings may limit the practicability of routinely using opinion leaders to influence practice.</p

    Impact of Scotland’s comprehensive, smoke-free legislation on stroke

    Get PDF
    &lt;p&gt;Background: Previous studies have reported a reduction in acute coronary events following smoke-free legislation. Evidence is lacking on whether stroke is also reduced. The aim was to determine whether the incidence of stroke, overalland by sub-type, fell following introduction of smoke-free legislation across Scotland on 26 March 2006.&lt;/p&gt; &lt;p&gt;Methods and Findings: A negative binomial regression model was used to determine whether the introduction of smokefree legislation resulted in a step and/or slope change in stroke incidence. The model was adjusted for age-group, sex, socioeconomic deprivation quintile, urban/rural residence and month. Interaction tests were also performed. Routine hospital administrative data and death certificates were used to identify all hospital admissions and pre-hospital deaths due to stroke (ICD10 codes I61, I63 and I64) in Scotland between 2000 and 2010 inclusive. Prior to the legislation, rates of all stroke, intracerebral haemorrhage and unspecified stroke were decreasing, whilst cerebral infarction was increasing at 0.97% per annum. Following the legislation, there was a dramatic fall in cerebral infarctions that persisted for around 20 months. No visible effect was observed for other types of stroke. The model confirmed an 8.90% (95% CI 4.85, 12.77, p,0.001) stepwise reduction in cerebral infarction at the time the legislation was implemented, after adjustment for potential cofounders.&lt;/p&gt; &lt;p&gt;Conclusions: Following introduction of national, comprehensive smoke-free legislation there was a selective reduction in cerebral infarction that was not apparent in other types of stroke.&lt;/p&gt

    A Self-Reference False Memory Effect in the DRM Paradigm: Evidence from Eastern and Western Samples

    Get PDF
    It is well established that processing information in relation to oneself (i.e., selfreferencing) leads to better memory for that information than processing that same information in relation to others (i.e., other-referencing). However, it is unknown whether self-referencing also leads to more false memories than other-referencing. In the current two experiments with European and East Asian samples, we presented participants the Deese-Roediger/McDermott (DRM) lists together with their own name or other people’s name (i.e., “Trump” in Experiment 1 and “Li Ming” in Experiment 2). We found consistent results across the two experiments; that is, in the self-reference condition, participants had higher true and false memory rates compared to those in the other-reference condition. Moreover, we found that selfreferencing did not exhibit superior mnemonic advantage in terms of net accuracy compared to other-referencing and neutral conditions. These findings are discussed in terms of theoretical frameworks such as spreading activation theories and the fuzzytrace theory. We propose that our results reflect the adaptive nature of memory in the sense that cognitive processes that increase mnemonic efficiency may also increase susceptibility to associative false memories

    Improved methods using the reverse transcriptase polymerase chain reaction to detect tumour cells

    Get PDF
    Reverse transcriptase polymerase chain reaction (RT-PCR) is increasingly used to detect small numbers of circulating tumour cells, though the clinical benefit remains controversial. The largest single contributing factor to the controversy of its value is the different approaches to sample processing. The aim of this study was to compare the sensitivity and reproducibility of RT-PCR for the detection of tumour cells after four commonly used different methods of sample processing. Using RT-PCR, one tumour cell spiked in 2 ml of whole blood was detected after analysis of separated mononuclear cell RNA, whole blood total or poly-A+RNA. No false positives were identified with any method. However, the reproducibility of tumour cell detection was reduced after isolation of the mononuclear cell fraction. Only analysis of poly-A+RNA had a sensitivity of 100% in all the cell spiking experiments. In patient blood samples, analysis of poly-A+RNA increased the number of blood samples positive for tyrosine hydroxylase (TH) mRNA compared with those positive after analysis of total RNA. This may reflect high levels of cDNA reducing the efficiency of the PCR. Isolation of poly-A+RNA increases the sensitivity and reproducibility of tumour cell detection in peripheral blood. © 1999 Cancer Research Campaig

    Direct Regulation of CLOCK Expression by REV-ERB

    Get PDF
    Circadian rhythms are regulated at the cellular level by transcriptional feedback loops leading to oscillations in expression of key proteins including CLOCK, BMAL1, PERIOD (PER), and CRYPTOCHROME (CRY). The CLOCK and BMAL1 proteins are members of the bHLH class of transcription factors and form a heterodimer that regulates the expression of the PER and CRY genes. The nuclear receptor REV-ERBα plays a key role in regulation of oscillations in BMAL1 expression by directly binding to the BMAL1 promoter and suppressing its expression at certain times of day when REV-ERBα expression levels are elevated. We recently demonstrated that REV-ERBα also regulates the expression of NPAS2, a heterodimer partner of BMAL1. Here, we show that REV-ERBα also regulates the expression another heterodimer partner of BMAL1, CLOCK. We identified a REV-ERBα binding site within the 1st intron of the CLOCK gene using a chromatin immunoprecipitation – microarray screen. Suppression of REV-ERBα expression resulted in elevated CLOCK mRNA expression consistent with REV-ERBα's role as a transcriptional repressor. A REV-ERB response element (RevRE) was identified within this region of the CLOCK gene and was conserved between humans and mice. Additionally, the CLOCK RevRE conferred REV-ERB responsiveness to a heterologous reporter gene. Our data suggests that REV-ERBα plays a dual role in regulation of the activity of the BMAL1/CLOCK heterodimer by regulation of expression of both the BMAL1 and CLOCK genes
    corecore