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Clostridium difficile infection control strategies require an understanding of its epidemiology. In this study, we analysed the toxin genotypes of 130 non-duplicate clinical isolates of C. difficile from a university hospital in Tokyo, Japan. Multilocus sequence typing (MLST) and eBURST analysis were performed for these isolates and nine strains previously analysed by polymerase chain reaction (PCR) ribotyping. Minimum inhibitory concentrations (MICs) were determined for six antibiotics, and the bacterial resistance mechanisms were investigated. Ninety-five toxigenic strains (73 %), including seven tcdA-negative, tcdB-positive and cdtA/ cdtB-negative strains (ABCDT) and three ABCDT strains, and 35 (27 %) non-toxigenic strains, were classified into 23 and 12 sequence types, respectively. Of these, sequence type (ST)17 (21.8 %) was the most predominant. MLST and eBURST analysis showed that 139 strains belonged to seven groups and singletons, and most ABCDT strains (98 %, 89/91) were classified into group 1. All isolates were susceptible to metronidazole, vancomycin and meropenem; the ceftriaxone, clindamycin and ciprofloxacin resistance rates were 49, 59 and 99 %, respectively. Resistance rates to ceftriaxone and clindamycin were higher in toxigenic strains than in non-toxigenic strains ( P < 0.001). All ST17 and ST81 strains were resistant to these antibiotics. The clindamycin- and fluoroquinolone-resistant strains carried erm(B) and mutations in GyrA and/or GyrB, respectively. To our knowledge, this is the first MLST-based study of the molecular epidemiology of toxigenic and non-toxigenic strains in Japan, providing evidence that non-toxigenic and toxigenic strains exhibit high genetic diversity and that toxigenic strains are more likely than non-toxigenic strains to exhibit multidrug resistance. [ABSTRACT FROM AUTHOR]

SUMMARY Streptococcus agalactiae (group B streptococcus; GBS) isolates (n = 150) from infants with invasive infections between 2006 and 2011 were analysed for capsular serotype, multilocus sequence type, and antibiotic susceptibility. In cases with late-onset disease (n = 115), primary meningitis was predominant (62.6%), but represented only 39.1% in cases with early-onset disease (n = 23). The most common serotype was III (58.7%), followed by Ia (21.3%) and Ib (12.7%). Sequence types (STs) of serotype III strains included ST17 (50.0%), ST19 (26.1%), ST335 (18.2%), ST27 (4.5%), and ST1 (1.1%). Predominant STs of serotypes Ia and Ib were ST23 (81.3%) and ST10 (84.2%), respectively. No penicillin-resistant strains were detected, but 22·0% of strains had mef(A/E), erm(A), or erm(B) genes, which mediate macrolide resistance. A new ST335, possessing an mef(A/E) gene belonging to clonal complex 19 gradually increased in frequency. Improved prevention of invasive GBS infections in infants requires timely identification, and ultimately vaccine development.

Background: We examined the usefulness of endoscopic color Doppler ultrasonography, using Levovist in evaluating the arterial blood flow, in patients with esophageal varices., Methods: The study involved 110 patients with esophageal varices who were examined using endoscopic color Doppler ultrasonography (ECDUS). We compared vessel images detected by pre-contrast ECDUS with those detected by enhanced ECDUS. We evaluated the detection rate of the pulsatile wave, and measured systolic velocity and end-diastolic velocity. We calculated the resistance index (RI), which demonstrates the resistance of peripheral vessels in arterial flow., Results: Color flow images of the pulsatile wave were obtained by pre-contrast ECDUS in 3 (2.7%) of the 110 patients. Color flow images of the pulsatile waves were obtained in 40 (36.4%) of the 110 patients by enhanced ECDUS using Levovist. That is, by using Levovist, a pulsatile wave could be delineated in 37 patients in whom pulsatile waves were previously undiagnosed via pre-contrast ECDUS. Color flow images of the pulsatile waves were detected in 37 (37.7%) of the 98 F2 varices and in 3 (25.0%) of the 12 F3 varices. Color flow images of the pulsatile wave were detected in 35 (40.2%) of the 87 red color (RC)(+) varices, and in 5 (21.7%) of the 23 RC(++) or RC (+++) varices. Next, we calculated the RI of the pulsatile wave, obtained by enhanced ECDUS using Levovist, in 40 patients. The RI ranged from 0.49 to 0.83 (mean, 0.67 +/- 0.09); there were nine patients with RIs of less than 0.60, and all 9 of these patients had both F2 and RC(+) type varices (100%)., Conclusions: Levovist contrast in ECDUS examinations suggests that arterial flow is involved in the formation of esophageal varices.