Additional file 1: of Ecological effects of cefepime use during antibiotic cycling on the Gram-negative enteric flora of ICU patients

Methods. This file describes the methods used to obtain and analyze the data presented in this manuscript and includes Table S1. (entitled “Markers for transmissible antibiotic resistance included in our in-house screening”) and additional references pertaining to the methodology. (DOCX 24 kb

Resolving Low-Expression Cell Surface Antigens by Time-Gated Orthogonal Scanning Automated Microscopy

We report a highly sensitive method for rapid identification and quantification of rare-event cells carrying low-abundance surface biomarkers. The method applies lanthanide bioprobes and time-gated detection to effectively eliminate both nontarget organisms and background noise and utilizes the europium containing nanoparticles to further amplify the signal strength by a factor of ∼20. Of interest is that these nanoparticles did not correspondingly enhance the intensity of nonspecific binding. Thus, the dramatically improved signal-to-background ratio enables the low-expression surface antigens on single cells to be quantified. Furthermore, we applied an orthogonal scanning automated microscopy (OSAM) technique to rapidly process a large population of target-only cells on microscopy slides, leading to quantitative statistical data with high certainty. Thus, the techniques together resolved nearly all false-negative events from the interfering crowd including many false-positive events