42 research outputs found

    A Comparison of Shiga-Toxin 2 Bacteriophage from Classical Enterohemorrhagic Escherichia coli Serotypes and the German E. coli O104:H4 Outbreak Strain

    Get PDF
    Escherichia coli O104:H4 was associated with a severe foodborne disease outbreak originating in Germany in May 2011. More than 4000 illnesses and 50 deaths were reported. The outbreak strain was a typical enteroaggregative E. coli (EAEC) that acquired an antibiotic resistance plasmid and a Shiga-toxin 2 (Stx2)-encoding bacteriophage. Based on whole-genome phylogenies, the O104:H4 strain was most closely related to other EAEC strains; however, Stx2-bacteriophage are mobile, and do not necessarily share an evolutionary history with their bacterial host. In this study, we analyzed Stx2-bacteriophage from the E. coli O104:H4 outbreak isolates and compared them to all available Stx2-bacteriophage sequences. We also compared Stx2 production by an E. coli O104:H4 outbreak-associated isolate (ON-2011) to that of E. coli O157:H7 strains EDL933 and Sakai. Among the E. coli Stx2-phage sequences studied, that from O111:H- strain JB1-95 was most closely related phylogenetically to the Stx2-phage from the O104:H4 outbreak isolates. The phylogeny of most other Stx2-phage was largely concordant with their bacterial host genomes. Finally, O104:H4 strain ON-2011 produced less Stx2 than E. coli O157:H7 strains EDL933 and Sakai in culture; however, when mitomycin C was added, ON-2011 produced significantly more toxin than the E. coli O157:H7 strains. The Stx2-phage from the E. coli O104:H4 outbreak strain and the Stx2-phage from O111:H- strain JB1-95 likely share a common ancestor. Incongruence between the phylogenies of the Stx2-phage and their host genomes suggest the recent Stx2-phage acquisition by E. coli O104:H4. The increase in Stx2-production by ON-2011 following mitomycin C treatment may or may not be related to the high rates of hemolytic uremic syndrome associated with the German outbreak strain. Further studies are required to determine whether the elevated Stx2-production levels are due to bacteriophage or E. coli O104:H4 host related factors

    A Signature of Maternal Anti-Fetal Rejection in Spontaneous Preterm Birth: Chronic Chorioamnionitis, Anti-Human Leukocyte Antigen Antibodies, and C4d

    Get PDF
    Chronic chorioamnionitis is found in more than one-third of spontaneous preterm births. Chronic chorioamnionitis and villitis of unknown etiology represent maternal anti-fetal cellular rejection. Antibody-mediated rejection is another type of transplantation rejection. We investigated whether there was evidence for antibody-mediated rejection against the fetus in spontaneous preterm birth.This cross-sectional study included women with (1) normal pregnancy and term delivery (n = 140) and (2) spontaneous preterm delivery (n = 140). We analyzed maternal and fetal sera for panel-reactive anti-HLA class I and class II antibodies, and determined C4d deposition on umbilical vein endothelium by immunohistochemistry. Maternal anti-HLA class I seropositivity in spontaneous preterm births was higher than in normal term births (48.6% vs. 32.1%, p = 0.005). Chronic chorioamnionitis was associated with a higher maternal anti-HLA class I seropositivity (p<0.01), significant in preterm and term birth. Villitis of unknown etiology was associated with increased maternal and fetal anti-HLA class I and II seropositivity (p<0.05, for each). Fetal anti-HLA seropositivity was closely related to maternal anti-HLA seropositivity in both groups (p<0.01, for each). C4d deposition on umbilical vein endothelium was more frequent in preterm labor than term labor (77.1% vs. 11.4%, p<0.001). Logistic regression analysis revealed that chronic chorioamnionitis (OR = 6.10, 95% CI 1.29–28.83), maternal anti-HLA class I seropositivity (OR = 5.90, 95% CI 1.60–21.83), and C4d deposition on umbilical vein endothelium (OR = 36.19, 95% CI 11.42–114.66) were associated with preterm labor and delivery.A major subset of spontaneous preterm births has a signature of maternal anti-fetal cellular and antibody-mediated rejections with links to fetal graft-versus-host disease and alloimmune reactions

    Jornada Estatal sobre Llegim en parella

    Get PDF
    Una de les activitats emblemàtiques de l'ICE de la UAB, gairebé des dels seu orígens a l'any 1968, són les jornades, que tenen com a objectiu afavorir l'actualització de coneixements i l'intercanvi d'experiències entre els professionals de l'educació d'un àmbit concret. En molts casos els continguts de les jornades queden recollits en unes actes, que fins ara es publicaven en paper o, darrerament, en format CD, amb un abast més aviat limitat. Tenint en compte que la difusió de la feina feta té un caràcter prioritari per a l'ICE i que els publicacions on-line n'amplien exponencialment, gairebé infinitament, les possibilitats, hem volgut encetar una "sèrie digital" de la "Col·lecció Jornades", a través de la qual canalitzarem totes les publicacions d'aquesta mena a partir d'ara. En el primer exemplar d'aquesta nova sèrie hi trobareu la sinopsi de la Primera Jornada "Llegim en parella"."Llegim en parella" va néixer com una proposta metodològica basada en l'aprenentatge entre iguals que té com a finalitat promoure la lectura entre els alumnes de les aules de primària i de secundària. Les escoles que s'han adherit a aquesta manera de treballar formen una xarxa, amb nodes a Catalunya, les Illes, l'Aragó i el País Basc, mitjançant la qual es coordinen i intercanvien experiències. Els dies 4 i 5 de maig del 2012, van tenir lloc a la Universitat Autònoma de Bacelona les Jornades estatals sobre Llegim en parella, organitzades per l'ICE i el GRAI, amb el suport del Departament d'Ensenyament de la Generalitat de Catalunya. Les jornades van ser ser un punt de trobada i reflexió sobre la pràctica i el coneixement construït per les xarxes de centres que a Catalunya, Euskadi i Aragó han implementat el programa Llegim en parella i com una oportunitat per presentar-lo a la comunitat educativa en general. Més de 160 professionals hi van prendre part. En la publicació hi trobareu els textos de les intervencions (conferències, tallers i comunicacions), així com els pòsters que s'hi varen presentar i un reportatge fotogràfic de les sessions. El textos es reprodueixen en la llengua en què varen ser presentats, atesa la procedència dels participants

    Toxicity of nano- and ionic silver to embryonic stem cells: a comparative toxicogenomic study

    No full text
    Abstract Background The widespread application of silver nanoparticles (AgNPs) and silver-containing products has raised public safety concerns about their adverse effects on human health and the environment. To date, in vitro toxic effects of AgNPs and ionic silver (Ag+) on many somatic cell types are well established. However, no studies have been conducted hitherto to evaluate their effect on cellular transcriptome in embryonic stem cells (ESCs). Results The present study characterized transcriptomic changes induced by 5.0 µg/ml AgNPs during spontaneous differentiation of mouse ESCs, and compared them to those induced by Ag+ under identical conditions. After 24 h exposure, 101 differentially expressed genes (DEGs) were identified in AgNP-treated cells, whereas 400 genes responded to Ag+. Despite the large differences in the numbers of DEGs, functional annotation and pathway analysis of the regulated genes revealed overall similarities between AgNPs and Ag+. In both cases, most of the functions and pathways impacted fell into two major categories, embryonic development and metabolism. Nevertheless, a number of canonical pathways related to cancer were found for Ag+ but not for AgNPs. Conversely, it was noted that several members of the heat shock protein and the metallothionein families were upregulated by AgNPs but not Ag+, suggesting specific oxidative stress effect of AgNPs in ESCs. The effects of AgNPs on oxidative stress and downstream apoptosis were subsequently confirmed by flow cytometry analysis. Conclusions Taken together, the results presented in the current study demonstrate that both AgNPs and Ag+ caused transcriptomic changes that could potentially exert an adverse effect on development. Although transcriptomic responses to AgNPs and Ag+ were substantially similar, AgNPs exerted specific effects on ESCs due to their nanosized particulate form

    MOESM2 of Toxicity of nano- and ionic silver to embryonic stem cells: a comparative toxicogenomic study

    No full text
    Additional file 2: Figure S2. Morphological changes of the differentiating EBs after exposure for 24 h to varying concentrations of AgNPs (A) or Ag+ (B). The concentrations of AgNPs or Ag+ used for the exposure (in ¾g/ml) are indicated by the numbers at the top left corner of each image

    Toxicogenomic study in rat thymus of F1 generation offspring following maternal exposure to silver ion

    Get PDF
    Male and female rats (26-day-old) were exposed to 0.0, 0.4, 4 or 40 mg/kg body weight silver acetate (AgAc) in drinking water for 10 weeks prior to and during mating. Sperm-positive females remained within their dose groups and were exposed to silver acetate during gestation and lactation. At postnatal day 26, the effect of silver ions on the developing F1 generation rat thymus was evaluated at the transcriptional level using whole-genome microarrays. Gene expression profiling analyses identified a dozen differentially expressed genes (DEGs) in each dose group using a loose criterion of fold change (FC) >1.5 and unadjusted p < 0.05, regardless of whether the analysis was conducted within each gender group or with both gender groups combined. No dose-dependent effect was observed on the number of DEGs. In addition, none of these genes had a false discovery rate (FDR) <0.05 after correction for multiple testing. These results in combination with the observation that thymus-to-body-weight ratios were not affected and no histopathological abnormalities were identified indicate that in utero exposure to silver ions up to 26.0 mg/kg (equivalent to 40.0 mg/kg silver acetate) did not have an adverse effect on the developing thymus

    Effects of providing manuscript editing through a combination of in-house and external editing services in an academic hospital.

    No full text
    BackgroundEnglish editing services are effective for improving manuscript quality as well as providing learning opportunities for non-native English-speaking authors. Herein, we describe the effects of a combined system of in-house and external editing services for handling large volumes of editing requests and providing personalized editing service in academic hospitals.MethodsWe established the Scientific Publications Team (SPT), an in-house editing team in Asan Medical Center in Seoul, Korea. The SPT is composed of two professional editors who manage editing requests sent to external companies while also providing one-on-one in-house editing services. We gathered author satisfaction data from 936 surveys between July 2017 and December 2018 and analyzed the number of editing requests and research publications by segmented regression analysis of interrupted time series data.ResultsThe SPT processed 3931 editing requests in 2017-2018, which was a marked increase compared with prior to its establishment (P = 0.0097). The authors were generally satisfied with the quality of editing services from both in-house and external editors. Upon conducting regular quality control, overall author satisfaction with one external company gradually increased over the course of one year (P for trend = 0.086). Author satisfaction survey results revealed that overall satisfaction of editing service was most strongly correlated with how well the edits conformed to the authors' intentions (R = 0.796), and was only weakly correlated with quick turnaround time (R = 0.355). We also observed a significant increase in the trend of the number of research publications (P = 0.0007) at one year after the establishment of the SPT.ConclusionProviding a combination of in-house and external editing services resulted in high author satisfaction and subsequent hospital-wide increases in manuscript writing and publication. Our model system may be adapted in academic hospitals to better address the editing needs of non-native English-speaking researchers
    corecore