Activity of mecillinam against Escherichia coli resistant to third-generation cephalosporins.

Objectives: To assess the activity of mecillinam against two groups of Escherichia coli: (i) a selection of international isolates with mechanisms of resistance caused by the presence of defined beta-lactamases; and (ii) isolates resistant to third-generation cephalosporins referred from across Wales.

Methods: Antibiotic susceptibility testing with mecillinam, meropenem, amoxicillin, co-amoxiclav, cefotaxime, piperacillin/tazobactam, ciprofloxacin, nitrofurantoin, trimethoprim and gentamicin was performed using the BSAC agar dilution method against 30 international strains of E. coli with known beta-lactamase presence.

New insights into the phylogeny of Entamoeba species provided by analysis of four new small-subunit rRNA genes.

Sequences of small-subunit rRNA genes have been obtained for four new isolates of Entamoeba. Phylogenetic analyses give new insights into the evolution of these organisms. A novel Entamoeba from pigs in Vietnam that produces uninucleate cysts proved to be unrelated to other uninucleated cyst-producing species.

Internal transcribed spacer dimorphism and diversity in Dientamoeba fragilis.

The internal transcribed spacer (ITS) region of the ribosomal RNA operon is frequently used for detecting sequence variation among closely related species as it is usually homogeneous within strains but evolves more rapidly than ribosomal RNA coding regions. We have studied this region in both genotypes of the human intestinal parasite Dientamoeba fragilis. In contrast to most organisms, we have identified extensive variation between copies of the sequence within the same strain.

Non-travel-associated hepatitis E in England and Wales: demographic, clinical, and molecular epidemiological characteristics.

Between 1996 and 2003, 186 cases of hepatitis E were serologically diagnosed. Of these, 17 (9%) were not associated with recent travel abroad. Patients were >55 years old (range, 56-82 years old) and tended to be male (76%).