1. Unit of Infectious Diseases, Department of Medical Sciences at Amedeo di Savoia Hospital, University of Turin, 10149 Turin, Italy
2. HIV Neurobehavioral Research Program, Department of Psychiatry, University of California San Diego (UCSD), San Diego, CA 92103, USA
3. Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego (UCSD), La Jolla, CA 92037, USA
4. VA San Diego Healthcare System and Veterans Medical Research Foundation, La Jolla, CA 92037, USA
5. Department of Medicine, Owen Clinic, University of California San Diego (UCSD), San Diego, CA 92037, USA