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SUMMARY: Polyamidoamine polymers were prepared by hydrogen-transfer polyaddition of 2-methylpiperazine to 2,29-bis(acrylamido)acetic acid sodium salt to yield PAA-1, polyaddition of amino-b-cyclodextrin and 2-methylpiperazine to 2,29-bis(acrylamido)acetic acid to give PAA-2 and polyaddition of the same amino-bcyclodextrin and 2-methylpiperazine to 1,4-bis(acryloyl)piperazine to produce PAA-3. These polymers were reacted with cisplatin to give products containing between 8 -70 wt.-% platinum. The amount of platinum released from the conjugates during incubation at pH 5.5 and pH 7.4 varied between 0 -20%/72 h. PAA-3-Pt showed pH-dependent platinum release. The PAA-platinates were generally less toxic towards lung tumour cell lines in vitro. The IC 50 for cisplatin being 2 -5 lg/mL and for the PAA-platinates 1 -130 lg/mL, this was only to be expected due to their very different cellular pharmacokinetics. In vivo experiments showed that the PAA-1-Pt and PAA-2-Pt were equi-active compared with cisplatin against an i.p. L1210 leukaemia model, confirming their ability to liberate biologically active platinum species. Whereas PAA-1-Pt was significantly less toxic than cisplatin, PAA-2-Pt did show toxicity on repeated dosing, suggesting further investigations are needed to establish the biocompatibility of PAAs containing pendant b-cyclodextrin. PAA-1-Pt is suitable for further in vivo preclinical study in a range of solid tumour models.

Abstract. During the last years, various methods and techniques have been used to estimate the seafloor topography with high accuracy. The topography is considered an important component for marine applications since several activities and infrastructures are being carried out at the bottom, column and surface of the sea. In this, study, freely and open distributed optical satellite images were used to obtain bathymetric data for shallow waters, (until 30 m below sea level) based on timeseries analysis of multispectral Sentinel-2 datasets. The ratio transform algorithm was implemented for twelve (12) monthly images covering thus a whole year. The different generated Digital Terrain Models (DTMs) were compared with high resolution LIDAR measurements. The results showed that bathymetry can be obtained from satellite data within a Root Mean Square Error (RMSE) ranging from 1.39 up to 2.56 m while more accurate results were generated during the summer period.