Rapid quantification of Staphylococcus aureus from endotracheal aspirates of ventilated patients: a proof-of-concept study.

Major concern for intubated patients is ventilator-associated pneumonia (VAP). Early detection of VAP and its causative microorganism(s) is a key challenge for clinicians. Diagnosis is based on clinical, radiological, and microbiological elements, the latter being provided 24-48h after sampling. According to practices, clinicians can sample endotracheal aspirates (ETAs) so as to check for patient colonization or perform ETA in case of VAP suspicion. In this proof-of-concept study, we report the evaluation of a semiautomated molecular method to rapidly quantify Staphylococcus aureus, one of the most involved microorganisms in VAP, directly from raw ETA samples. After evaluation using artificial ETA samples, our method was applied on 40 clinical ETA samples. All S. aureus-positive samples were successfully detected and quantified. Our method can provide an efficient sample preparation protocol for all raw ETA samples, combined with an accurate quantification of the bacterial load, in less than 3h 30min.

Synthesis of all-cis 2,5-imino-2,5-dideoxy-fucitol and its evaluation as a potent fucosidase and galactosidase inhibitor.

We here describe a simple and efficient synthetic method for a non-hydrolysable precursor of a GDP-fucose analogue: The synthesis of the racemic aminofuranofucitol 3 from sorbic alcohol by nitroso-Diels-Alder reaction. This 'all-cis-pyrrolidine', with all substituents occupying a cis position, has been determined as a potent inhibitor of α-L-fucosidase and a moderate inhibitor of α- and ß-D-galactosidase. The good recognition of this fucose moiety analogue by specific enzymes is thus confirmed. The C-anomeric bond in this particular structure is in the ß-position and makes this compound an interesting candidate for further chemical modifications. Influence of the methyl and hydroxymethyl groups on the inhibition potency is discussed.