Collage Vol. I

JUDY COCHRAN: Editorial MICHAEL TANGEMAN: Haikus 2-5 ELISE ALBRECHT, CURTIS PLOWGIAN: French Calligrams 6 JASON VARDEN: Waiting 7 ALEXANDER GREEN: Photo 8 EDUARDO JARAMILLO: Formas violentas 9-11 GABRIELE DILLMANN: Photo 12 MICHAEL GOLDSBERG: Funf fur Ashley 13 MEGAN CARLSON: Fur Jared (German) 14 MAGGIE GLOVER: For Jared 14-15 CHRIS FAUR: Painting 16 LINDSEY ESHELMAN: Stuhl (The Chair) 17 HALLE THOMPSON, GWENN DOBOS: Les Bouches 18 JILL BOO: Lacheln (A Smile) 19 ALEXANDER GREEN: Photo 20 JULIA GRAWEMEYER: Villanelle 21, Expressions francaises (French Figures) 22-23, Pour me rappeler (So that I\u27d remember) 24 MICHEL CLIQUET: Photo 25 CHARLES O\u27KEEFE: Photos 26-28 LINE LERYCKE: Photos 29-32 MICHEL CLIQUET: Pierre docile (Docile Stone) 29-32 LOGAN FAVIA: Ataraxia 33 AVRITA SINGH: Absence 34 RACHEL GROTHEER: Compassion 35, Ligne (Line) 36, Nuit, douce nuit (Night, gentle night) 37, Rouge (Red) 38, Bonjour Bleu (Hello Blue) 39, Ligne courbe (Curved Line) 40 AMELIA DUNLAP: Compassion 41-42 KYLE SIMPSON: Separation 43 ALEXANDER GREEN: Photo 44 GWENN DOBOS: Ataraxia 45 SARAH SLOTKIN: Separation 46 CURTIS PLOWGIAN: Absence 47 ELISA VER MERRIS: Photo 48, Attachement (Attachment) 49 JENNIFER JOHNSON: Attachement (Attachment)50 ANNA KELLY: Compassion 51 RICHARD BANAHAN: Photo 52, Mon grand-pere et moit (My grandfather and me) 53 MEREDITH KATZ: Separation 54 BRENDA HEATER: Compassion 55 ZACHARY WALSH: Ataraxia 56 MICHEL CLIQUET: Photos 57-5

Extracellular DNA impedes the transport of vancomycin in Staphylococcus epidermidis biofilms pre-exposed to sub-inhibitory concentrations of vancomycin

Staphylococcus epidermidis biofilm formation is responsible for the persistence of orthopedic implant infections. Previous studies have shown that exposure of S. epidermidis biofilms to sub-MICs of antibiotics induced an increased level of biofilm persistence. BODIPY FL-vancomycin (a fluorescent vancomycin conjugate) and confocal microscopy were used to show that the penetration of vancomycin through sub-MIC-vancomycin-treated S. epidermidis biofilms was impeded compared to that of control, untreated biofilms. Further experiments showed an increase in the extracellular DNA (eDNA) concentration in biofilms preexposed to sub-MIC vancomycin, suggesting a potential role for eDNA in the hindrance of vancomycin activity. Exogenously added, S. epidermidis DNA increased the planktonic vancomycin MIC and protected biofilm cells from lethal vancomycin concentrations. Finally, isothermal titration calorimetry (ITC) revealed that the binding constant of DNA and vancomycin was 100-fold higher than the previously reported binding constant of vancomycin and its intended cellular d-Ala-d-Ala peptide target. This study provides an explanation of the eDNA-based mechanism of antibiotic tolerance in sub-MIC-vancomycin-treated S. epidermidis biofilms, which might be an important factor for the persistence of biofilm infections