1. Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, North Dakota, USA
2. Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, Texas, USA
3. Department of Biological Sciences, Wayne State University, Detroit, Michigan, USA
4. Department of Chemistry and Program in Molecular & Cellular Biology, University of Massachusetts Amherst, Amherst, Massachusetts, USA