Unprecedented incorporation of α-emitter radioisotope 213Bi into porphyrin chelates with reference to a daughter isotope mediated assistance mechanism.

International audienceFor the first time, α-emitter radioisotope (213)Bi has been incorporated into porphyrin chelates, with rates matching with the short period of the radionuclide. An in situ transmetalation mechanism involving the daughter isotope (209)Pb is expected to boost the (213)Bi radiolabeling process

The neurohypophysial hormones of the egg-laying mammals identification of arginine vasopressin in the platypus (ornithorhynchus anatinus)

Two neurohypophysial peptides have been purified from acetone desiccated posterior pituitary glands of the platypus (Ornithorhynchus anatinus) by molecular sieving and high-pressure liquid chromatography. A single pressor peptide, having an amino acid composition and a chromatographic retention time identical to those of arginine vasopressin, has been identified. A single oxytocic peptide has been isolated that ressembles oxytocin by its chromatographic retention time, but lack of material has prevented to obtain a correct amino acid composition. The pressor peptide is roughly four times more abundant than the oxytocic peptide. Neurohypophysial hormones of platypus seem similar to those of echidna, the other living prototherian, and to those of most placental mammals