1,721,321 research outputs found
(Dis)regolazione delle emozioni, depressione e alterazioni del sonno: misure soggettive e topografia corticale EEG.
No full text
Au(III) complexes with N-methylglycine dithiocarbamate: synthesis, characterization and anticancer activity
No full textComplessi ditiocarbammici di oro (III) eloro impiego come antitumorali - Dithiocarbamate complexes of gold(III) and their use as antitumor agents
No full textL’invenzione è relativa a complessi quadrato-planari ditiocabammici di oro(III), al loro processo di sintesi ed al loro impiego terapeutico per il trattamento di patologie tumorali. I complessi di oro(III) dell’invenzione hanno infatti dimostrato di avere un vantaggioso effetto farmacologico in quanto più efficaci rispetto al cis-platino. Inoltre tali complessi dell’oro(III) risultano non presentare né fenomeni di resistenza crociata né di tossicità tipici del cis-platino. - The synthesis of claimed planar square gold(III) dithiocarbamic complexes for use as antitumor agents is described. The compds. with substituted dithiocarbamate and 2 halogen (Cl, Br) ligands are defined by Markush structures. Several complex compds. were synthesized by std. procedures and the products were characterized by IR, 1H-NMR and 13C-NMR spectroscopy, elemental anal., m.p., soly., and elec. cond. The compds. were tested for toxicity and antitumor activity in vitro using human tumor cell lines and in mice with transplanted solid and liq. tumors. The gold complexes had antitumor activities comparable with the effects of cisplatin, but showed less cross-resistance development and less toxicity compared to cisplatin. The gold complexes can be formulated with std. pharmaceutical excipients into forms suitable for oral treatment use (emulsions, suspensions, powders, gelatin capsules, tablets). The formulations can be also used for topical and transdermal treatments and for purging tumor cells from bone marrow autotransplants
Can a mixed damage interfere with DNA-protein cross-links repair?
No full textSome photochemical and photobiological properties of 4,5',8-trimethylpsoralen (TMP) have been studied in comparison with 1,4,6,8-tetramethyl-2H-furo[2,3-h]quinolin-2 one (FQ) and 8-methoxypsoralen (8-MOP). The TMP and FQ can photobind to mammalian cell DNA in vivo, by UVA irradiation, forming DNA-protein cross-links (DPC), but only TMP shows a strong capacity of inducing interstrand cross-links (ISC). The mechanism of DPC formation was studied using the double irradiation method in Chinese hamster ovary (CHO) cells, and DPC were detected by alkaline elution. Both TMP and FQ induce covalent diadducts linking together DNA and proteins. Studying the formation of double strand breaks (DSB) in CHO cells we observed that TMP induced a low amount of DSB, similar to 8-MOP. TMP and 8-MOP induced chromosomal aberrations in CHO cells to the same extent, while FQ appeared to be more active. Our data suggest that the ISC induced by TMP could trap enzymes involved in DPC repair
2,6-Dimethyl-9-methoxy-4H-pyrrolo[3,2,1-ij]quinolin-4-one, a new compound with unusual photosensitizing properties. -
No full textSome photobiological properties of 2,6-dimethyl-9-methoxy-4H-pyrrolo[3,2,1-ij]quinolin-4-one (PQ) have been studied in comparison with 8-methoxypsoralen (8-MOP). In Ehrlich cells, PQ induced a moderate inhibition in DNA and RNA syntheses in the dark, which appeared to be more pronounced upon UVA irradiation. In contrast to 8-MOP, in the presence of UVA, PQ also affected protein synthesis. Likewise marked antiproliferative effects were also observed in the study of the clonal growth of CHO cells cultivated in vitro. Using alkaline elution and CHO cells, a moderate formation of single-strand breaks (SSBs) and of DNA-protein cross-links (DPCs) was observed by incubation in the dark; upon UVA irradiation the amount of both lesions increased greatly, whereas no inter-strand cross-links (ISCs) were formed. As expected, 8-MOP did not damage DNA in the dark, but induced SSBs, ISCs and DPCs in the presence of WA. The induction of SSBs by both compounds seems to be directly related to a photochemical event rather than to incisions during DNA repair. As the induction of ISCs, and also the formation of DPCs by 8-MOP and UVA, appears to be based on a two-step reaction involving photo-bound 8-MOP-DNA moieties. In contrast, the formation of DPCs by PQ and UVA seems to involve photosensitization by free PQ molecules connected with SSB and DPC formation rather than with a DNA photo-binding activity. The PQ activity observed in the dark could probably be ascribed to a moderate inhibition of topoisomerases
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