1. Department of Anesthesiology, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada.
2. Department of Pharmacology, Dalhousie University, Halifax, Canada.
3. Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada.
4. Department of Microbiology and Immunology, Dalhousie University, Halifax, Canada.