Nanocomposites obtained by the decoration of graphene-based materials with silver nanoparticles (AgNPs) have received increasing attention owing to their antimicrobial activity. However, the complex synthetic methods for their preparation have limited practical applications. This study aims to synthesize novel NanoHybrid Systems based on graphene, polymer, and AgNPs (namely, NanoHy-GPS) through an easy microwave irradiation approach free of reductants and surfactants. The polymer plays a crucial role, as it assures the coating layer/substrate compatibility making the platform easily adaptable for a specific substrate. AgNPs' loading (from 5% to 87%) can be tuned by the amount of Silver salt used during the microwave-assisted reaction, obtaining spherical AgNPs with average sizes of 5-12 nm homogeneously distributed on a polymer-graphene nanosystem. Interestingly, microwave irradiation partially restored the graphene sp2 network without damage of ester bonds. The structure, morphology, and chemical composition of NanoHy-GPS and its subunits were characterized by means of UV-vis spectroscopy, thermal analysis, differential light scattering (DLS), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray analysis (EDX), Atomic Force Microscopy (AFM), and High-Resolution Transmission Electron Microscopy (HRTEM) techniques. A preliminary qualitative empirical assay against the typical bacterial load on common hand-contacted surfaces has been performed to assess the antibacterial properties of NanoHy-GPS, evidencing a significative reduction of bacterial colonies spreading.

Genomic studies suggest an association of circadian clock genes with bipolar disorder (BD) and lithium response in humans. Therefore, we tested mice mutant in various clock genes before and after lithium treatment in the forced swim test (FST), a rodent behavioral test used for evaluation of depressive-like states. We find that expression of circadian clock components, including Per2, Cry1 and Rev-erbα, is affected by lithium treatment, and thus, these clock components may contribute to the beneficial effects of lithium therapy. In particular, we observed that Cry1 is important at specific times of the day to transmit lithium-mediated effects. Interestingly, the pathways involving Per2 and Cry1, which regulate the behavior in the FST and the response to lithium, are distinct as evidenced by the phosphorylation of GSK3β after lithium treatment and the modulation of dopamine levels in the striatum. Furthermore, we observed the co-existence of depressive and mania-like symptoms in Cry1 knock-out mice, which resembles the so-called mixed state seen in BD patients. Taken together our results strengthen the concept that a defective circadian timing system may impact directly or indirectly on mood-related behaviors.

Chemotherapeutics such as platinum-based drugs are commonly used to treat several cancer types, but unfortunately, their use is limited by several side effects, such as high degradation of the drug before entering the cells, off-target organ toxicity and development of drug resistance. An interesting strategy to overcome such limitations is the development of nanocarriers that could enhance cellular accumulation in target cells in addition to decreasing associated drug toxicity in normal cells. Here, we aim to prepare and characterize a graphene-oxide-based 2D nanoplatform functionalised using highly branched, eight-arm polyethylene-glycol, which, owing to its high number of available functional groups, offers considerable loading capacity over its linear modalities and represents a highly potent nanodelivery platform as a versatile system in cancer therapy. The obtained results show that the GO@PEG carrier allows for the use of lower amounts of Pt drug compared to a Pt-free complex while achieving similar effects. The nanoplatform accomplishes very good cellular proliferation inhibition in osteosarcoma, which is strictly related to increased cellular uptake. This enhanced cellular internalization is also observed in glioblastoma, although it is less pronounced due to differences in metabolism compared to osteosarcoma. The proposed GO@PEG nanoplatform is also promising for the inhibition of migration, especially in highly invasive breast carcinoma (i.e., MDA-MB-231 cell line), neutralizing the metastatic process. The GO@PEG nanoplatform thus represents an interesting tool in cancer treatment that can be specifically tailored to target different cancers.

Converging evidence shows that neurochemical systems are crucial mediators of nicotine dependence. Our present study evaluates the effect of 3-month chronic nicotine treatment on the levels of multiple quaternary ammonium compounds as well as glutamate and gamma aminobutyric acid in the rat prefrontal cortex, dorsal striatum and hypothalamus. We observed a marked decrease of acetylcholine levels in the dorsal striatum (22.88%, p<0.01), reflecting the impact of chronic nicotine in local interneuron circuits. We found decreases of carnitine in the dorsal striatum and prefrontal cortex (19.44%, p<0.01; 13.58%, p<0.01, respectively), but robust enhancements of carnitine in the hypothalamus (26.59%, p<0.01), which may reflect the alterations in food and water intake during chronic nicotine treatment. Finally, we identified an increase of prefrontal cortex glutamate levels (8.05%, p<0.05), supporting previous studies suggesting enhanced prefrontal activity during chronic drug use. Our study shows that quaternary ammonium compounds are regulated in a highly brain region specific manner during chronic nicotine treatment, and provides novel insights into neurochemical regulation during nicotine use.