Radiolabelled peptides for oncological diagnosis

Radiolabelled receptor-binding peptides targeting receptors (over)expressed on tumour cells are widely under investigation for tumour diagnosis and therapy. The concept of using radiolabelled receptor-binding peptides to target receptor-expressing tissues in vivo has stimulated a large body of research in nuclear medicine. The 111In-labelled somatostatin analogue octreotide (OctreoScan™) is the most successful radiopeptide for tumour imaging, and was the first to be approved for diagnostic use. Based on the success of these studies, other receptor-targeting peptides such as cholecystokinin/gastrin analogues, glucagon-like peptide-1, bombesin (BN), chemokine receptor CXCR4 targeting peptides, and RGD peptides are currently under development or undergoing clinical trials. In this review, we discuss some of these peptides and their analogues, with regard to their potential for radionuclide imaging of tumours

Karyotypic Data on 28 Species of Scinax (Amphibia: Anura: Hylidae): Diversity and Informative Variation

The hylid frog genus Scinax is the most species-rich within Hylinae, with more than 100 recognized species grouped in the S. catharinae and S. ruber clades. The karyotypes of 14 species of the S. catharinae clade and 14 of the S. ruber clade were analyzed, several of them for the first time. All studied species presented 2n = 2x = 24 biarmed chromosomes (FN = 48) and no identifiable sex chromosomes. There are two alternate states associated with the size and morphology of pair 1, corresponding to the S. catharinae clade and to the S. ruber clade. The morphology of pairs 2 and 6 also differentiate the species of both major clades. Species of the S. ruber clade in general have Ag-NORs in pair 11, as is commonly observed among hylines with 2n = 24. The Ag-NORs' position in the long arms of pair 11 is interstitial in S. fuscomarginatus, S. fuscovarius, S. nasicus, S. similis, S. squalirostris, and S. uruguayus, and terminal in S. acuminatus, S. curicica, S. duartel, S. granulatus, S. hayii, and S. perereca. The single exception among species of the S. ruber clade is S. alter, which has terminal Ag-NORs at the long arms of pair 3. Most species of the S. catharinae clade have Ag-NORs in pair 6, representing a putative synapomorphy of this clade, while the Ag-NORs in pair 11 that occur in S. canastrensis are most parsimoniously interpreted as a reversion. C-banding is predominantly centromeric, but in the S. catharinae clade there is a greater amount of heterochromatin than in the S. ruber clade. This study corroborates the occurrence of informative variation, some already considered in a previous cladistic analysis, and reports new characters, outlining the significance of cytogenetic data for the systematics of Scinax.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP