1. Department of Biological Chemistry; Johns Hopkins University; Baltimore Maryland
2. Department of Zoology; University of Wisconsin-Madison; Madison Wisconsin
3. Dipartimento di Patologia Chirurgica, Medica, Molecolare e Area Critica; Università di Pisa; Pisa Italy
4. Department of Medicine; University of Alabama Birmingham; Birmingham Alabama
5. Magnetic Resonance Facility at Madison; Madison Wisconsin