No significant differences between the numbers
of colonies recovered on plates with or without antibiotics were observed (data not shown). Histology of chinchilla bullae Following sacrifice, the chinchilla ears were dissected, fixed with 10% neutral buffered formalin, and decalcified with 5% formic acid. Each ear was cut at the midline in the sagittal plane, and both halves were processed and paraffin-embedded. Step sections of the distal halves were performed and the resulting slides were stained with hematoxylin-eosin selleck products (H&E) for analysis. One of us (A.N.W.), a Board-certified pathologist, Adavosertib scored randomized and blinded sections from the same step-sections of each ear for the relative level of the inflammatory response, with the control (buffer only) ears being scored as 0 (no inflammation), with the most inflammation being designated as 4+. Ribonuclease (RNase) activity assays Varying amounts of purified VapD, VapX, or Cat (chloramphenicol acetyltransferase) proteins were incubated at 37°C for 30 minutes with 25 pmol of RNaseAlert substrate (Integrated DNA Technologies, GDC-0068 datasheet Coralville, IA) using the manufacturer’s buffer in a final volume of 25 μl. The RNaseAlert
substrate is a single stranded RNA with a fluorophore (FAM) on one end and a quencher on the other. When cleaved, the substrate fluoresces brightly. This sensitive assay allows us to monitor RNase activity in real time. Negative controls consisted of the MagneHis protein elution buffer with no protein, and 0.6 μg of the Cat and VapX proteins. The reactions were placed in a Bio-Rad white 48-well PCR plate, covered with optical film and incubated in a MiniOpticon thermocycler at 37°C. Plate reads were taken every 5 minutes for 30 minutes. The average
relative fluorescence units (RFU) from two independent assays are reported. All solutions used were nuclease free or treated with diethyl pyrocarbonate. Statistical analysis Data are presented as the mean ± standard ID-8 deviation (SD). Differences among multi-group treatments were determined by one-way ANOVA using the VassarStats website for statistical computation (http://faculty.vassar.edu/lowry/VassarStats.html). P values of ≤0.05 were considered significant, with significant differences further analyzed using a Tukey HSD post hoc test. Acknowledgements This study was funded by a National Institutes of Health grant DC010187 from the National Institute on Deafness and Other Communication Disorders (NIDCD) to D.A.D. NIDCD had no role in the design, collection, analysis, and interpretation of the data, nor any role in the writing of the manuscript or in the decision to submit the manuscript for publication. We are grateful to Wenzhou Hong, Medical College of Wisconsin, for sharing his expertise in the chinchilla model; to Shirley A.