1. Physical Molecular BiologyLaboratory of Receptor BiologyGene ExpressionNational Cancer InstituteNational Institutes of HealthBethesdaMaryland20892-5055USA
2. Department of Cellular Biotechnology and HaematologyUniversity of Rome ‘La Sapienza’00161RomeItaly
3. Department of Chemistry and Chemical EngineeringPolytechnic UniversityBrooklynNew York11201USA