Clonal spread of SCCmec type IV methicillin-resistant Staphylococcus aureus between community and hospital

ABSTRACTThe staphylococcal chromosome cassette (SCC)mec types of 382 hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) isolates in Taiwan were analysed over a 7-year period (1999–2005). There was an abrupt increase in SCCmec type IV in HA-MRSA during 2005. The molecular epidemiology of a subset (n = 69) of HA-MRSA isolates with SCCmec types III, IV or V was characterised and compared with that of community-acquired MRSA (CA-MRSA) (n = 26, collected during 2005). Pulsed-field gel electrophoresis revealed three major pulsotypes (A, B and C) and 15 minor clones. Pulsotypes B and C, which contained isolates carrying SCCmec types IV and V, respectively, included both CA-MRSA and HA-MRSA isolates. Among 24 toxin genes analysed, five genes had significant differential distribution between CA-MRSA and SCCmec type III HA-MRSA. Furthermore, among SCCmec type IV isolates, the seb gene was detected more commonly in HA-MRSA. Analysis of representative members of the three major pulsotypes by multilocus sequence typing revealed two sequence types (STs), namely ST239 (SCCmec III) and ST59 (SCCmec IV or SCCmec V). This suggests that ST59:SCCmec IV, which is usually community-acquired, has become an important nosocomial pathogen in the hospital studied

Capturing a c2 daisy chain using the threading-followed-by-swelling approach

We have used the "threading-followed-by-swelling'' approach to fix a daisy chain structure in solution, leading to the isolation of a captured [c2] daisy chain in 77% yield

Protecting a squaraine near-IR dye through its incorporation in a slippage-derived 2 Rotaxane

[GRAPHICS] The photophysical properties and chemical stability of a squaraine derivative were enhanced after using Na+ ions to template a high-yield slippage synthesis of a [2]rotaxane from the dye and a molecular cage