1. Department of Pharmacy Services, Memorial Hermann Hospital - Texas Medical Center, Houston, Texas
2. Department of Neurosurgery and Neurology, University of Texas McGovern Medical School at Houston, Houston, Texas
3. Pharmacology, Molecular Biology, and Microbiology, Case Western Reserve University, Cleveland, Ohio
4. Research Service, Cleveland VA Medical Center, Cleveland, Ohio
5. Department of Internal Medicine, University of Texas McGovern Medical School at Houston, Houston, Texas
6. Bacterial Molecular Genetics Unit, Universidad El Bosque, Bogota, Colombia