465 research outputs found

    Use of heavy metals in swine feed and its association with the co-selection of metal tolerant and multi-drug resistant Salmonella

    Get PDF
    This study was conducted to characterize the role of chemical interventions, biocides and heavy metal micronutrients, in particular, in swine production systems on the emergence of heavy metal and biocide tolerant Salmonella and its association with antimicrobial resistance. A total of 353 Salmonella isolates with different antimicrobial resistance profiles identified from 36 barns exposed to three different classes of biocides were analyzed. The sources of isolates included feed (n=30), fecal (n=226), and environment (n=97) samples that were systematically selected

    Motive-demand dynamics creating a social context for students’ learning experiences in a making and design environment

    Get PDF
    Making and design environments, often referred to as makerspaces, have aroused recent educational interest. These environments typically consist of spaces that support interest-driven engagement in hands-on creative activities with a range of digital artefacts. Although a variety of benefits from participating in making and design activities have been proposed, we currently have limited understanding of students’ learning experiences in makerspaces situated in schools. Following Hedegaards’ conceptualisations, we investigate motive-demand dynamics in students’ social activity in a school-based digital making and design environment, ‘The FUSE Studio’. We highlight our findings via vignettes selected from 65 h of video recordings of 94 students (aged between 9 and 12 years old) carrying out activities; the recordings were collected intermittently from an elective course over one semester. Our study illustrates how the students’ learning experiences were shaped through tension-laden interplay between the motives and demands of their activity situated across personal, relational and institutional contexts. The findings make visible how established ways of working and being at school interacted and came into tension with the students’ motive orientations, thereby limiting and at times transforming the social context of their learning. Our work also demonstrates how the analysis of motive-demand dynamics offers one useful conceptual tool to unpack students’ learning experiences in novel learning environments.Peer reviewe

    Resistin-Like Molecule-β Inhibits SGLT-1 Activity and Enhances GLUT2-Dependent Jejunal Glucose Transport

    Get PDF
    International audienceOBJECTIVE: An increased expression of RELM-beta (resistin-like molecule-beta), a gut-derived hormone, is observed in animal models of insulin resistance/obesity and intestinal inflammation. Intestinal sugar absorption is modulated by dietary environment and hormones/cytokines. The aim of this study was to investigate the effect of RELM-beta on intestinal glucose absorption. RESEARCH DESIGN AND METHODS: Oral glucose tolerance test was performed in mice and rats in the presence and the absence of RELM-beta. The RELM-beta action on glucose transport in rat jejunal sacs, everted rings, and mucosal strips was explored as well as downstream kinases modulating SGLT-1 and GLUT2 glucose transporters. RESULTS: Oral glucose tolerance test carried out in rodents showed that oral administration of RELM-beta increased glycemia. Studies in rat jejunal tissue indicated that mucosal RELM-beta promoted absorption of glucose from the gut lumen. RELM-beta had no effect on paracellular mannitol transport, suggesting a transporter-mediated transcellular mechanism. In studies with jejunal mucosa mounted in Ussing chamber, luminal RELM-beta inhibited SGLT-1 activity in line with a diminished SGLT-1 abundance in brush border membranes (BBMs). Further, the potentiating effect of RELM-beta on jejunal glucose uptake was associated with an increased abundance of GLUT2 at BBMs. The effects of RELM-beta were associated with an increased amount of protein kinase C betaII in BBMs and an increased phosphorylation of AMP-activated protein kinase (AMPK). CONCLUSIONS: The regulation of SGLT-1 and GLUT2 by RELM-beta expands the role of gut hormones in short-term AMPK/protein kinase C mediated control of energy balance

    Blood pressure, lipids, and obesity are associated with reteinopathy - The Hoorn study

    Get PDF
    OBJECTIVE - To study potential risk factors for retinopathy in diabetic and nondiabetic individuals. RESEARCH DESIGN AND METHODS - The Hoorn Study is a population-based study including 2,484 50- to 74-year-old Caucasians. A subsample of 626 individuals stratified by age, sex, and glucose tolerance underwent extensive measurements during 1989-1992, including ophthalmologic examination and two-field 45-degree fundus photography. The prevalence of (diabetic) retinopathy was assessed among individuals with normal glucose metabolism (NGM) and impaired glucose metabolism (IGM) and individuals with newly diagnosed diabetes mellitus (NDM) and known diabetes mellitus (KDM) (new World Health Organization 1999 criteria). RESULTS - The prevalence of retinopathy was 9% in NGM, 11% in IGM, 13% in NDM, and 34% in KDM. Retinopathy worse than minimal nonproliferative diabetic retinopathy was present in 8% in KDM and 0-2% in other glucose categories. The prevalence of retinopathy was positively associated with elevated blood pressure, BMI, cholesterol, and triglyceride serum levels in all glucose categories. The age-, sex-, and glucose metabolism category-adjusted odds ratios were 1.5 (95% CI 1.2-1.9), 1.3 (1.0-1.7), and 1.3 (1.0-1.6) per SD increase of systolic blood pressure, BMI, and total cholesterol concentration, respectively, and 1.2 (1.0-1.5) per 50% increase of triglyceride level. Elevated blood pressure and plasma total and LDL cholesterol levels showed associations with retinal hard exudates. CONCLUSIONS - Retinopathy is a multifactorial microvascular complication, which, apart from hyperglycemia, is associated with blood pressure, lipid concentrations, and BMI

    Dissolving the digital divide : Creating coherence in young people's social ecologies of learning and identity building

    Get PDF
    This chapter discusses current research on educational efforts to connect school learning with young people’s digital practices in- and out-of-school. Instead of focusing on divides between in-school and out-of-school learning or between the “digital generation” and other age groups, in this chapter we discuss what recent research says about the ways in which school can become a space in which young people’s digital practices can transformatively converge with schooling, and how this convergence is related to their learning and identity building. We begin our narrative reflection of current research by focusing on the myth of digital natives. Next, we will conceptualize recent efforts to researching and understanding young people’s engagement, learning and identity building across sites and contexts. We will then turn to illuminating some key rationales of current educational research on creating convergence in young people’s social ecologies via the use of digital technologies and media. We conclude our reflections by pointing out that although there are some promising findings on how digital technologies and media can create convergence in young people’s engagement and learning across sites and contexts, less research attention is given to young people’s personal sense-making and self-making mediated by their digital practices, and how formal education could build on those practices for academic, vocational and/or civic ends.Peer reviewe

    Association between biocide use and antimicrobial resistance of Salmonella in swine production environment

    Get PDF
    Swine are important reservoirs of antimicrobial resistant Salmonella. The emergence and dissemination of multidrug resistant (MDR) Salmonella enterica has also become a major concern globally. Studies on the association between biocide usc and emergence and persistence of MDR Salmonella in swine production environment are very limited. The aim of this study was to determine the role of specific classes of biocides (disinfectants) in the emergence and persistence of multidrug resistant Salmonella in swine production environments

    Population Structure and Molecular Epidemiology of Campylobacter coli Isolates of Porcine Origin from Different Geographic Regions and Production Systems

    Get PDF
    The genotypic diversity of C. coli isolates recovered from pigs from different geographic regions and production systems were investigated by multilocus sequence typing (MLST) method. A total of 99 C. coli isolates, 50 from Ohio and 49 from Wisconsin, representing the different production systems (conventional and antibiotic free) and resistance patterns (pan-susceptible, EryTet+ and others) were analyzed. Fifty different sequence types (ST) were identified by sequencing the seven housekeeping genes (aspA, ginA. gltA, glyA,pgm, tkt, and uncA). Seven of them were new STs (ST-3813, 3814,3815,3816, 3817, 3818 and 3819) identified for the first time. Of these, three resulted from new allele sequence at tkt and uncA loci and the remaining resulted from new combinations of the previously described alleles
    corecore