Neosporin

Rats were anesthetized with 5% isoflurane and maintained with 1.5–2.0% isoflurane in oxygen-enriched air. After the heads were secured in a stereotactic frame, the surgical procedure was carried out as described in previous studies.^{28 (link),29 (link)} A 4-mm craniotomy was made over the left parietal cortex (bregma: 1 mm posterior, 1 mm lateral). To produce a CCI, the bone flap was removed and the dura was impacted with a benchmark stereotaxic impactor (IM10244; Leica Biosystems, Inc., Richmond, VA) with a diameter of 3 mm at a velocity of 5.5 m/s and a dwell time of 100 ms. To produce a broad range of injury for regression analysis with APTw, impact depths were varied over a wide range (1, 3, or 5 mm). For the purposes of analysis in this study, we refer to the 1-, 3-, and 5-mm depths as mild, moderate, and severe injury, respectively, although it was appreciated that the 5-mm depth would be greater than what is typically used in the rat CCI model. Rats in the sham group were subjected to anesthesia and a scalp incision, but did not undergo a craniotomy or impact. In all groups, the scalp was closed with nylon sutures and antibiotic ointment was applied (Neosporin; Johnson & Johnson, New Brunswick, NJ).

General supplies, reagents, and growth media were purchased from Fisher Scientific (Hampton, NH). An 8-ply 100% cotton gauze was purchased from Kendall Curity®; Coviden (Mansfield, MA). Five clinically-relevant topical products were purchased via the pharmacy at the Department of Veterans Affairs in Salt Lake City: gentamicin sulfate ointment USP, 0.1% (Perrigo Company, Allegan, MI), mupirocin ointment USP, 2% (Glenmark Pharmaceuticals, Mahwah, NJ), silver sulfadiazine cream, USP 1% (Ascend Laboratories, Montvale, NJ), Neosporin® (400 U Bacitracin Zinc– 3.5mg Neomycin Sulfate– 5,000 U Polymixin B Sulfate; Johnson and Johnson, New Brunswick, NJ), Altabax® (retapamulin ointment) 1%, (GlaxoSmithKline, Barnard Castle, County Durham, United Kingdom). Hyaluronic acid (HA; 1.01 MDa– 1.8 MDa) was purchased from Lifecore Biomedical (Chaska, MN; catalog #HA15M-5). This HA is a bacterial fermentation product of Streptococcus pyogenes. Reagents and chemicals for synthesizing CZ-01179 were purchased from Sigma Aldrich (St. Louis, MO). Cellulose discs (6 mm) were purchased from BD (Sparks, MD), and collagen coupons were cut from HeliPlug® Collagen Wound Dressing (Integra LifeSciences, Plainsboro, NJ). BacLight™ Bacterial Viability kits were purchased from Molecular Probes (Eugene, OR). The Nunc™ Lab-Tek™ chamber slide system was purchased from ThermoScientific™ (Waltham, MA).