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A workshop on high-impact meteorological events in Italy was jointly organized by the newly formed Italia Meteo Agency (AIM) and the Italian Association of Atmospheric Sciences and Meteorology (AISAM) on September 27, 2022. The aim of the workshop was to promote the sharing of the experiences that all operational and research meteorological centers in Italy have gained on specific types of high-impact events, favoring the establishment of a common know-how of Italian operational meteorology.

Liposomes containing monosialoganglioside (GM1) or polyethylene glycol (PEG) lipid derivatives have prolonged circulation in the blood. This favours liposome extravasation to tumour sites. In this report it is shown that inclusion of GM1, PEG550‐DPPE or PEG2000‐DPFE in liposomes containing biotin‐DPPE significantly diminished the ability of vesicles to bind to streptavidin in vitro. Steric inhibition due to the bulky head group of these lipids was least for biotin‐DPPE liposomes containing GM1. Biodistribution studies in C26 tumour‐bearing mice showed that GM1‐liposomes containing small amounts of biotin‐DPPE have long circulation life‐times in the blood. Using fluorescent microscopic techniques, liposomes containing both GM1and biotin‐DPPE were detected within extra‐vascular spaces in tumours. In addition it was shown that biotin‐DPPE in GM1‐liposomes bound streptavidin in situ. These results suggest that GM1‐liposomes containing biotin‐DPPE have potential use as diagnostic or therapeutic reagents in pre‐targeting applications dependent on the high‐affinity interaction of biotin with streptavidin.

The imaging of cerebral gliomas with radiolabelled monoclonal antibodies (MoAbs) has been previously reported. However, previous studies have been hampered by the drawback of a low tumour to non-tumour ratio. In order to overcome this problem we have developed a three-step pre-targeting method using the avidin-biotin system. The rationale of this technique consists in vivo labelling of biotinylated MoAbs targeted onto tumour deposits, when most of the unbound antibodies have been cleared from the bloodstream as avidin-bound complexes. The anti-tenascin MoAb BC2, specific for the majority of gliomas, was biotinylated and 1 mg was administered i.v. in 20 patients with histologically documented cerebral lesions. After 24–36 h, 5 mg avidin was injected i.v. followed 24 h later by a third i.v. injection of 0.2 mg PnAO-biotin labelled with 15–20 tnCi technetium-99m. No evidence of toxicity was observed. Whole-body biodistribution was measured at 20 min, 3 h and 5 h post-injection. [99mTc]PnAO-bio-tin had a fast blood clearance and was primarily excreted through the biliary system. A dedicated single-photon emission tomography system was used to acquire brain tomographic images 1–2 h after the administration of [99mTc]PnAO-biotin. Tumours were detected in 15/18 glioma patients with a tumour to non-tumour ratio of up 14:1. This three-step method, based on the sequential administration of anti-tenascin MoAb BC2, avidin and [99mTc]PnAO-biotin, can support computed tomography or magnetic resonance imaging for the diagnosis and follow-up of patients with glioma. Further studies are required to evaluate the potential of this technique for therapeutic application.