1. Research Service, Louis Stokes Cleveland Department of Veterans Affairs, Cleveland, Ohio, USA
2. Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
3. J. Craig Venter Institute, Rockville, Maryland, USA
4. Department of Pediatrics and Communicable Disease, University of Michigan Medical School, Ann Arbor, Michigan, USA
5. Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio, USA