1. Department of Pathology, Division of Neuropathology, Baltimore, Maryland, USA
2. NeuralStem, Inc., Gaithersburg, Maryland, USA
3. Department of Neurology, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
4. Department of Neuroscience, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
5. Department of Psychiatry and Behavioral Sciences, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA