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The synthesis and self-assembly of a 3D aerogel built by graphene oxide (GO) and a modified polyethylene glycol (PEG) was achieved by a multi-step synthetic procedure, involving the preparation of an amino-terminated PEG (PEG-NH2) and the subsequent coupling with GO by carbodiimide in water, exploiting the carboxyl and epoxy moieties of GO and –NH2 terminations of the biopolymer. The resulting nanohybrid hydrogel was successively converted into an aerogel via dialysis plus freeze-drying [1] and fully characterized. FTIR, Raman, XPS, XRD and BET measurements were performed to confirm the successful modification for each reaction step, while morphological, mechanical and hemolytic tests were performed on the final device, which was found to display an ultralight and highly porous (99.7%) network, intriguing mechanical properties and biocompatibility.

Introduction.The prevalence of overweight and obesity in children is rapidly increasing in many countries. For that it has been interesting to investigate the eating habits of 8-9 y-old Tuscany children by paying attention to their meals frequency per day and their food choices in total and in relation to children?s Body Mass Index (BMI) classes. In addition we considered some environment factors that could affect the children eating behaviours, such as mother?s BMI and their education level. Methods. A statistical sample of 3,076 (1,583 males, 1,493 females), 8-9 year-old school-children was collected; weight and height were measured using standardized personnel and instruments. BMI classes were calculated using Cole et al.?s cutoff for children and adolescents. In order to evaluate the consumption frequency of individual meals and various foods, a Food Frequency Questionnaire (FFQ) was used, which was completed by the children themselves at school. A self-administered questionnaire revealed the weight and height of parents and their educational levels. Three educational levels were established: high, medium and low. Results. The results showed that 92.3% of children ate breakfast from 4-7 times a week, the vast majority at home, while only 3% declared consuming breakfast never or almost never. The most preferred breakfast consisted of milk and biscuits for all children?s BMI classes. 95.9% of children reported having mid-morning snack at school; fruit juice and tea are the most frequently consumed liquid foods, and pizza, salami sandwiches and pre-packaged snacks are the most frequently consumed solid foods in all BMI classes. 93.6% ate afternoon snack for the most part at home, even if 12% of children reported consuming it elsewhere; fruit juice and tea with pizza, sandwiches and pre-packaged snacks are still the most highly consumed foods by all children?s BMI classes. The consumption frequency of breakfast (P inf. 0.001), mid-morning (P inf. 0.05) and afternoon snack (P inf. 0.05) of 8-9 y-old Tuscany children decrease with increase the children?s BMI classes. The same tendency may be noted for the consumption frequency of breakfast in relation to mother?s BMI (P inf. 0.05) and their education level (P inf. 0.05). This data strengthens the thesis that some home environments can affect the children?s eating behaviours. Conclusion. No substantial differences in food choices at the meals analyzed were determined among normal weight, over weight and obese children. Children of normal weight had a greater tendency to consume meals more regularly. Mother?s BMI and their education level can have influence on children?eating behaviours., Journal of Preventive Medicine and Hygiene, Vol 47, No 3 (2006)

Introduction. Overweight and obesity in the developmental age has become a public health problem. For this reason, prevention projects must be developed in advance with the aim to involve not only children, but their parents as well. Our objective is to evaluate the accuracy of the mothers? perceptions of adolescent nutritional status. Methods. Cross-sectional study. We selected a statistical sample of 3,076 subjects (1,583 males, 1,493 females), 8-9 y-old school-children of 164 3rd-grade elementary school classes from throughout Tuscany, as well as their mothers. The mothers? information was gathered via self-administered questionnaires, while the children were given an eating behaviour survey under the supervision of qualified personnel. Mothers? education level (self-reported) height and weight were collected; children?s height and weight were measured. The former were asked how they perceived their children?s body image. Results. A correlation exists between the mothers? perceptions of the nutritional state of their children via the silhouettes and the BMI classes of the children, which is equal to 80% with a k-Cohen for agreement equal to 0.58 (SE = 0.02; P : 0.0001). However, no correlation exists between the mothers? responses to the question ?In your opinion, is your child ??? and the child?s actual BMI class (the exact percentage correlation is equal to 75%, with a k-Cohen for agreement equal to 0.43 SE = 0.014; P : 0.0001). Discussion. Mothers have an accurate perception of the nutritional status of their children, correctly choosing the silhouette that corresponds to the child?s BMI profile without variation by gender. We can assume that mothers in our sample have a good concept about healthy nutritional status., Journal of Preventive Medicine and Hygiene, Vol 47, No 1 (2006)

A new class of pyrrolo[2',3':3,4]cyclohepta[1,2-d][1,2]oxazoles was synthesized for the treatment of hyperproliferative pathologies, including neoplasms. The new compounds were screened in the 60 human cancer cell lines of the NCI drug screen and showed potent activity with GI50 values reaching the nanomolar level, with mean graph midpoints of 0.08-0.41 μM. All compounds were further tested on six lymphoma cell lines, and eight showed potent growth inhibitory effects with IC50 values lower than 500 nM. Mechanism of action studies showed the ability of the new [1,2]oxazoles to arrest cells in the G2/M phase in a concentration dependent manner and to induce apoptosis through the mitochondrial pathway. The most active compounds inhibited tubulin polymerization, with IC50 values of 1.9-8.2 μM, and appeared to bind to the colchicine site. The G2/M arrest was accompanied by apoptosis, mitochondrial depolarization, generation of reactive oxygen species, and PARP cleavage.

In the frame of this work, we present, for the first time, the synthesis and self-assembly of an aerogel built by graphene oxide-polyethylene glycol. The synthetic route involves at first the coupling of GO with an amino-terminated polyethylene glycol sample by carbodiimide in aqueous environment, and the subsequent conversion of the hydrogel achieved into an aerogel via freeze-drying. The 3D PEGylated graphene-based aerogel, characterized by spectroscopic, morphological, structural and mechanical analyses, displays an ultralight and highly porous (99.7%) network and possesses high mechanical properties together with a good biocompatibility.

Pyrrolo[3′,2′:6,7]cyclohepta[1,2-b]pyridines were synthesized as a new class of tricyclic system in which the pyridine ring is annelated to a cycloheptapyrrole scaffold, with the aim of obtaining new photosensitizing agents with improved antiproliferative activity and lower undesired toxic effects. A versatile synthetic pathway was approached, which allowed the isolation of derivatives of the title ring system with a good substitution pattern on the pyrrole moiety. Photobiological studies revealed that the majority of the new compounds showed a potent cytotoxic effect upon photoactivation with light of the proper wavelength, especially when decorated with a 2-ethoxycabonyl group and a N-benzyl substituted moiety, with EC50 values reaching the submicromolar level. The mechanism of action was evaluated.

A new series of pyrrolo[3′,2′:6,7]cyclohepta[1,2-d]pyrimidin-2-amines, was conveniently prepared using a versatile and high yielding multistep sequence. A good number of derivatives was obtained and the cellular photocytotoxicity was evaluated invitro against three different human tumor cell lines with EC50 (0.08–4.96μM) values reaching the nanomolar level. Selected compounds were investigated by laser flash photolysis. The most photocytotoxic derivative, exhibiting a fairly long-lived triplet state (τ ∼ 7μs) and absorbance in the UV–Vis, was tested in the photo-oxidations of 9,10-anthracenedipropionic acid (ADPA) by singlet oxygen. The photosentizing properties are responsible for the compounds’ ability to photoinduce massive cell death with involvement of mitochondria.

An easy method to achieve a fluorinated graphene oxide–silica nanohybrid (GOSF) is presented. Graphene oxide (GO) was synthesized by Hummer's modified method, the GO–silica nanohybrid (GOS) was obtained via Fischer esterification, the fluorinated moiety (3-pentadecafluoroheptyl-5-perfluorophenyl-1,2,4-oxadiazole) was introduced by nucleophilic substitution operated by the hydroxyl functionalities onto the GOS surface. Full characterization of the new materials confirmed the formation of covalent bonds between the graphene oxide/silica hybrid matrix and the fluorinated moieties. The proposed methodology offers an easy way to get fluorinated carbon/silica hybrid nanomaterials avoiding the harsh reaction conditions usually involved in the preparation of fluorinated materials, and allowing the selective immobilization of specific fluorotails. Moreover, performed oxygen uptake and release kinetics showed that the introduction of fluorinated moieties increases the oxygen exchange, making the material interesting for prospective applications in the biomedical field, as oxygen delivery system, as filler for biocompatible materials, and in the preparation of membranes for the purification of water.

Over the last years, many efforts were dedicated to the development of sustainable sorbent materials. The interest concerns a wide range of applications. Oily products and utilization are increasing all over the world as far as the possibility of spill oily accidents. In this direction, production of sponges showing lipophilic properties allows for the proper disposal of oily waste and does not cause secondary pollution. In this work, it is proposed an eco-friendly technology to prepare a polycaprolactone (PCL) biodegradable sponge for the selective absorption of oil from water. PCL biopolymer matrix was melt mixed with water-soluble porogen agents and then leached in water to obtain a porous 3D structure. The intrinsic lipophilic nature of PCL made the porous device able to selectively absorb oily pollutants showing, moreover, with high efficiency and high reusability potential. Devices are characterized from morphological and mechanical point of view. Oily waste uptake was evaluated by considering 3 different oily waste (olive oil, motor oil, gasoline) and considering 50 recycles.

Concept Graphene, a single layer of sp2-hybridized carbon atoms arranged in a honeycomb two-dimensional (2-D) crystal lattice, has evoked enormous interest throughout the scientific community since its first appearance in 2004. Due to its unique structure and geometry, graphene possesses remarkable physical-chemical properties (including large specific surface area and biocompatibility) that enable it to be an ideal material for several applications, ranging from quantum physics, nanoelectronics, energy research, catalysis and engineering of nanocomposites and biomaterials. In the area of nanomedicine, graphene and its derivatives can be exploited for a broad range of applications, including a new generation of biosensors, nanocarriers for drug delivery and probes for cell and biological imaging [1]. In particular, graphene oxide (GO), synthesized by intensive oxidation of crystalline graphite and then turned into a monolayer material by sonication, consists of aromatic planes and polar functional groups which consequently provide it an excellent capability to adsorb aromatic compounds via ?-? stacking and hydrogen bonding. In order to improve its biocompatibility and physiological stability, some biocompatible polymer can be introduced onto GO. Among the commercially available polymers, poly(ethylene glycol) (PEG) is a very useful reagent in biology because of its minimal toxicity, biocompatibility, protein resistance, and good solubility in water or other common solvents [2]. Motivations and Objectives Sorafenib is a small molecule that acting as a multi-kinases inhibitor blocks tumor-cell proliferation and tumor angiogenesis. It increases the rate of apoptosis in a wide range of tumor models and is the first drug that is clinically approved for patients with advanced hepatocellular carcinoma (HCC) [3]. In the present study, we aimed to develop a GO-PEG based carrier for enhanced delivery and controlled release of sorafenib into specific cancer cells. Results and Discussion Herein, we developed a GO-PEG nanocarrier for enhanced delivery and controlled release of sorafenib into specific cancer cells. GO-PEG was first synthesized dispersing GO in bi-distilled water followed by adding PEG2000-NH2. For the preparation of sorafenib loaded GO-PEG a solution of sorafenib in DMSO was added to an aqueous GO-PEG dispersion at pH 8.4, and the obtained solution was kept under magnetic stirring at room temperature overnight. The empty and drug-loaded GO-PEG were characterized in terms of size, zeta potential, polydispersity, morphology and drug loading capacity. The release kinetic studies, carried out in an appropriate medium mimicking the physiological environment, confirmed that this system permits a controlled release of sorafenib.

GO-based composites have attracted increasing attention due to their improved properties: in this context Silica-GO nanohybrids are currently used in many fields, ranging from biomedicine to optoelectronics. In recent years growing interest of the materials community has been posed on the functionalization of graphene materials with fluorine: Fluorinated graphene oxide has been proven to be the first carbon material for Magnetic Resonance Imaging without the addition of magnetic nanoparticles,1 moreover, has proven to absorb NIR-laser energy and efficiently transform it into heat, so that fluorinated graphene oxide has been suggested as a contrast agent for MRI, ultrasound and photoacoustic imaging, and also as targetable drug carrier and NIR laser inducible hyperthermic material that can ablate thermosensitive cancer cells.2 In this study we prepared a novel hybrid material with the particular combination of a GO matrix, grafted by silica nanoparticles and further functionalized by highly fluorinated oxadiazole moieties (FOXAR) by nucleophilic substitution (Figure). The characterization of the materials, performed by FTIR, SEM-EDAX, 13C {1H} MAS NMR and 19F MAS NMR, allowed to state that FOXAR is covalently bonded to the GOS. Moreover, oxygen uptake and release kinetics were performed on oxygen saturated aqueous solutions containing GOS or GOSF at atmospheric pressure by means of a previously reported saturation method,3 at 25°C and at 0.5 mg/ml. Collected data highlight that fluoro-functionalization increases the dissolved oxygen content at saturation: notably, for GOSF we observe a faster O2 uptake than unfluorinated GOS and a slower O2 release during desaturation.

A synthesis of the naturally occurring xanthone toxyloxanthone B is described, in which the key step is the regioselective addition of a methyl salicylate to a substituted benzyne, followed by cyclization of the intermediate aryl anion to form the xanthone, the regiochemistry of the aryne addition being confirmed by X-ray crystallography. Subsequent introduction of the pyran ring by [3,3]-rearrangement and deprotection completed the synthesis.

A series of 40 derivatives of the [1,2]oxazolo[5,4-e]indazoles ring system have been prepared with good yields using a versatile and convenient route. Annelation of the [1,2]oxazole ring on the indazole-4-one system was achieved by reaction of the corresponding enaminoketones with hydroxylamine hydrochloride. Derivatives of the title ring system were tested by the National Cancer Institute of Bethesda and one of them (13t) showed growth-inhibitor activity against all the 54 human tumour cell lines generally at low micromolar concentrations.