1,744 research outputs found

    Ablation of kynurenine 3-monooxygenase rescues plasma inflammatory cytokine levels in the R6/2 mouse model of Huntington's disease

    Get PDF
    Kynurenine 3-monooxygenase (KMO) regulates the levels of neuroactive metabolites in the kynurenine pathway (KP), dysregulation of which is associated with Huntington’s disease (HD) pathogenesis. KMO inhibition leads to increased levels of neuroprotective relative to neurotoxic metabolites, and has been found to ameliorate disease-relevant phenotypes in several HD models. Here, we crossed KMO knockout mice to R6/2 HD mice to examine the effect of KMO depletion in the brain and periphery. KP genes were dysregulated in peripheral tissues from R6/2 mice and KMO ablation normalised levels of a subset of these. KP metabolites were also assessed, and KMO depletion led to increased levels of neuroprotective kynurenic acid in brain and periphery, and dramatically reduced neurotoxic 3-hydroxykunurenine levels in striatum and cortex. Notably, the increased levels of pro-inflammatory cytokines TNFa, IL1β, IL4 and IL6 found in R6/2 plasma were normalised upon KMO deletion. Despite these improvements in KP dysregulation and peripheral inflammation, KMO ablation had no effect upon several behavioural phenotypes. Therefore, although genetic inhibition of KMO in R6/2 mice modulates several metabolic and inflammatory parameters, these do not translate to improvements in primary disease indicators—observations which will likely be relevant for other interventions targeted at peripheral inflammation in HD

    Designing an automated clinical decision support system to match clinical practice guidelines for opioid therapy for chronic pain

    Get PDF
    Abstract Background Opioid prescribing for chronic pain is common and controversial, but recommended clinical practices are followed inconsistently in many clinical settings. Strategies for increasing adherence to clinical practice guideline recommendations are needed to increase effectiveness and reduce negative consequences of opioid prescribing in chronic pain patients. Methods Here we describe the process and outcomes of a project to operationalize the 2003 VA/DOD Clinical Practice Guideline for Opioid Therapy for Chronic Non-Cancer Pain into a computerized decision support system (DSS) to encourage good opioid prescribing practices during primary care visits. We based the DSS on the existing ATHENA-DSS. We used an iterative process of design, testing, and revision of the DSS by a diverse team including guideline authors, medical informatics experts, clinical content experts, and end-users to convert the written clinical practice guideline into a computable algorithm to generate patient-specific recommendations for care based upon existing information in the electronic medical record (EMR), and a set of clinical tools. Results The iterative revision process identified numerous and varied problems with the initially designed system despite diverse expert participation in the design process. The process of operationalizing the guideline identified areas in which the guideline was vague, left decisions to clinical judgment, or required clarification of detail to insure safe clinical implementation. The revisions led to workable solutions to problems, defined the limits of the DSS and its utility in clinical practice, improved integration into clinical workflow, and improved the clarity and accuracy of system recommendations and tools. Conclusions Use of this iterative process led to development of a multifunctional DSS that met the approval of the clinical practice guideline authors, content experts, and clinicians involved in testing. The process and experiences described provide a model for development of other DSSs that translate written guidelines into actionable, real-time clinical recommendations.http://deepblue.lib.umich.edu/bitstream/2027.42/78267/1/1748-5908-5-26.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78267/2/1748-5908-5-26.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78267/3/1748-5908-5-26-S3.TIFFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78267/4/1748-5908-5-26-S2.TIFFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78267/5/1748-5908-5-26-S1.TIFFPeer Reviewe

    Genetic and biochemical analyses of chromosome and plasmid gene homologues encoding ICL and ArCP domains in Vibrioanguillarum strain 775

    Get PDF
    Anguibactin, the siderophore produced by Vibrio anguillarum 775 is synthesized from 2,3-dihydroxybenzoic acid (DHBA), cysteine and hydroxyhistamine via a nonribosomal peptide synthetase (NRPS) mechanism. Most of the genes encoding anguibactin biosynthetic proteins are harbored by the pJM1 plasmid. In this work we report the identification of a homologue of the plasmid-encoded angB on the chromosome of strain 775. The product of both genes harbor an isochorismate lyase (ICL) domain that converts isochorismic acid to 2,3-dihydro-2,3-dihydroxybenzoic acid, one of the steps of DHBA synthesis. We show in this work that both ICL domains are functional in the production of DHBA in V. anguillarum as well as in E. coli. Substitution by alanine of the aspartic acid residue in the active site of both ICL domains completely abolishes their isochorismate lyase activity in vivo. The two proteins also carry an aryl carrier protein (ArCP) domain. In contrast with the ICL domains only the plasmid encoded ArCP can participate in anguibactin production as determined by complementation analyses and site-directed mutagenesis in the active site of the plasmid encoded protein, S248A. The site-directed mutants, D37A in the ICL domain and S248A in the ArCP domain of the plasmid encoded AngB were also tested in vitro and clearly show the importance of each residue for the domain function and that each domain operates independently.

    BPS dyons and Hesse flow

    Full text link
    We revisit BPS solutions to classical N=2 low energy effective gauge theories. It is shown that the BPS equations can be solved in full generality by the introduction of a Hesse potential, a symplectic analog of the holomorphic prepotential. We explain how for non-spherically symmetric, non-mutually local solutions, the notion of attractor flow generalizes to gradient flow with respect to the Hesse potential. Furthermore we show that in general there is a non-trivial magnetic complement to this flow equation that is sourced by the momentum current in the solution.Comment: 25 pages, references adde

    How are "teaching the teachers" courses in evidence based medicine evaluated? A systematic review

    Get PDF
    Background Teaching of evidence-based medicine (EBM) has become widespread in medical education. Teaching the teachers (TTT) courses address the increased teaching demand and the need to improve effectiveness of EBM teaching. We conducted a systematic review of assessment tools for EBM TTT courses. To summarise and appraise existing assessment methods for teaching the teachers courses in EBM by a systematic review. Methods We searched PubMed, BioMed, EmBase, Cochrane and Eric databases without language restrictions and included articles that assessed its participants. Study selection and data extraction were conducted independently by two reviewers. Results Of 1230 potentially relevant studies, five papers met the selection criteria. There were no specific assessment tools for evaluating effectiveness of EBM TTT courses. Some of the material available might be useful in initiating the development of such an assessment tool. Conclusion There is a need for the development of educationally sound assessment tools for teaching the teachers courses in EBM, without which it would be impossible to ascertain if such courses have the desired effect

    Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

    Get PDF
    Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

    Why Um Helps Auditory Word Recognition: The Temporal Delay Hypothesis

    Get PDF
    Several studies suggest that speech understanding can sometimes benefit from the presence of filled pauses (uh, um, and the like), and that words following such filled pauses are recognised more quickly. Three experiments examined whether this is because filled pauses serve to delay the onset of upcoming words and these delays facilitate auditory word recognition, or whether the fillers themselves serve to signal upcoming delays in a way which informs listeners' reactions. Participants viewed pairs of images on a computer screen, and followed recorded instructions to press buttons corresponding to either an easy (unmanipulated, with a high-frequency name) or a difficult (visually blurred, low-frequency) image. In all three experiments, participants were faster to respond to easy images. In 50% of trials in each experiment, the name of the image was directly preceded by a delay; in the remaining trials an equivalent delay was included earlier in the instruction. Participants were quicker to respond when a name was directly preceded by a delay, regardless of whether this delay was filled with a spoken um, was silent, or contained an artificial tone. This effect did not interact with the effect of image difficulty, nor did it change over the course of each experiment. Taken together, our consistent finding that delays of any kind help word recognition indicates that natural delays such as fillers need not be seen as ‘signals’ to explain the benefits they have to listeners' ability to recognise and respond to the words which follow them

    The virtues of small grain size: Potential pathways to a distinguishing feature of Asian wheats

    Get PDF
    Increase in grain/seed size recurrently features as a key element in the ‘domestication syndrome’ of plants (cf. Zohary and Hopf 2000; Fuller et al. 2014). In the context of its spread across Eurasia, however, the grain size of one of the world's major crop species underwent a substantial reduction. Between the fifth and second millennia BC, the grain length in a number of species of Triticum, collectively known as free-threshing wheat, decreased by around 30%. In order to understand and help account for this trend, we have obtained direct radiocarbon measurements from 51 charred wheat grains and measured the dimensions of several hundred grains from Asia to establish when and where that size diminution occurred. Our results indicate that the pace of a eastward/southward spread was interrupted around 1800 BC on the borders of the distinct culinary zone recognized by Fuller and Rowlands (2011), but regained pace around 200–300 years later in central-east China with a diminished grain size. We interpret this as evidence of a period of active crop selection to suit culinary needs, and consider whether it constitutes a distinct episode in the general character of genetic intervention in domesticated species.Financial support was provided by the European Research Council, under grant 249642 (FOGLIP), UKIERI – UK & India Collaborative Educational Research Initiative, and the International Center for Advanced Renewable Energy and Sustainability, Washington University in St. Louis

    DNA immunization as a technology platform for monoclonal antibody induction

    Get PDF
    To combat the threat of many emerging infectious diseases, DNA immunization offers a unique and powerful approach to the production of high-quality monoclonal antibodies (mAbs) against various pathogens. Compared with traditional protein-based immunization approaches, DNA immunization is efficient for testing novel immunogen designs, does not require the production or purification of proteins from a pathogen or the use of recombinant protein technology and is effective at generating mAbs against conformation-sensitive targets. Although significant progress in the use of DNA immunization to generate mAbs has been made over the last two decades, the literature does not contain an updated summary of this experience. The current review provides a comprehensive analysis of the literature, including our own work, describing the use of DNA immunization to produce highly functional mAbs, in particular, those against emerging infectious diseases. Critical factors such as immunogen design, delivery approach, immunization schedule, use of immune modulators and the role of final boost immunization are discussed in detail
    corecore