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ABSTRACT. The in vitro susceptibilities of 285 isolates of Escherichia coli from preweaned and postweaned pigs with diarrhea and edema disease were tested with the 15 commonly used antimicrobial drugs by an agar dilution minimal inhibitory concentration procedure according to National Committee for Clinical Laboratory Standards (NCCLS) guidelines. All E. coli isolates tested in this study belonged to enterotoxigenic E. coli, attaching and effacing E. coli, or Shiga toxin-producing E. coli. Field isolates had low MIC 90 for ceftiofur (1 µg/ml). No correlation in antimicrobial resistance was found in three types of E. coli. Escherichia coli strains such as enterotoxigenic E. coli (ETEC), attaching and effacing E. coli (AEEC), and Shiga toxin-producing E. coli (STEC) are associated with diarrhea and edema disease in pigs. ETEC has 2 types of virulence factors, fimbrial adhesins and enterotoxins [5,14]. The production of attaching and effacing lesions by AEEC strains is associated with a chromosomal determinant, eaeA [7]. Shiga toxin 2e (Stx2e) produced by STEC plays an important role in the pathogenesis of edema disease in postweaned pigs [6,12]. AEEC have been identified as a cause of diarrhea in pigs [7]. The characteristic intestinal lesion resulting from AEEC is the attaching and effacing (A/E) histopathology, characterized by intimate bacterial adherence to enterocytes and disruption of the underlying cytoskeleton [15].Antimicrobial resistance is one of the main concerns for health professionals dealing with bacterial disease. The current trend worldwide is to reduce antibiotic use in animal production in favor of good husbandry practices and vaccination, as means to raise healthier animals. Acknowledging the susceptibility profiles of a given bacterium can help to select appropriate treatment for the infections caused by it, which reduces failure rates, and saves time and money. Isolation of such a pathogenic E. coli may be necessary for efficient treatment since numerous non-pathogenic E. coli mainly inhabit the intestinal tracts of pigs. This is a key point since mis-isolation of the causal strain could lead to treatment failure and an increase in antimicrobial resistance, but most of antimicrobial susceptibility studies did not focus on pathogenic E. coli prior to antimicrobial susceptibility procedures. The objective of this study was to select the pathogenic E. coli among E. coli isolated from pigs with diarrhea and edema disease in Korea, and determine the antimicrobial susceptibility of these pathogenic isolates by means of new standardized procedures for the antimicrobial susceptibility test for animal pathogens issued by the National Committee for Clinical Laboratory Standards (NCCLS) [16].Between 1995 and 1998, 853 isolates of E. coli were isolated from 957 diarrheic piglets younger than 14 days; and 250 isolates of E. coli were isolated from 294 postweaned pigs with diarrhea and edema disease submitted from all over Korea to the Department of Veterinary Pathology, Seoul National University. Specime...

High mobility group box 1 (HMGB1) is a prototypic alarmin and plays an important role in the pathogenesis of inflammatory process in spontaneous preterm birth. This study was conducted to compare the levels of HMGB1 in amniotic fluid and amnion membranes in women with chorioamnionitis/intra-amniotic inflammation to the levels in healthy controls. We also aimed to elucidate the involvement of microRNA-548 (miR-548) in regulating HMGB1 expression and its function in human amniotic epithelial cells (hAECs). A bioinformatics analysis predicted the binding of HMGB1 by the miR-548 cluster. A repressed and forced expression assay in hAECs was performed to investigate the causal relationship between the miR-548 cluster and HMGB1. The levels of HMGB1 in amniotic fluid and amnion membranes were significantly higher in patients with intra-amniotic inflammation/chorioamnionitis than in those without inflammation. The miR-548 was significantly under-expressed in amnion membranes from patients with chorioamnionitis than in normal term controls. Repressed expression of miR-548 up-regulated HMGB1 expression in hAECs and increased its release from hAECs. Moreover, forced expression of miR-548 suppressed HMGB1 and inflammatory cytokines in hAECs, which increased when treated with lipopolysaccharide. These results suggest miR-548 can alter the inflammatory responses in hAECs, and might be involved in the pathogenesis of preterm birth by regulating HMGB1.

Larvae, nymphs, and adult stages of 3 species of ixodid ticks were collected by tick drag methods in Seoul during June-October 2013, and their infection status with severe fever with thrombocytopenia syndrome (SFTS) virus was examined using RT-PCR. During the period, 732 Haemaphysalis longicornis, 62 Haemaphysalis flava, and 2 Ixodes nipponensis specimens were collected. Among the specimens of H. longicornis, the number of female adults, male adults, nymphs, and larvae were 53, 11, 240, and 446, respectively. Ticks were grouped into 63 pools according to the collection site, species, and developmental stage, and assayed for SFTS virus. None of the pools of ticks were found to be positive for SFTS virus gene.