Robust, reproducible, recyclable SERS substrates: monolayers of gold nanostars grafted on glass and coated with a thin silica layer.

We prepared and characterized recyclable surface enhanced Raman spectroscopy (SERS) active glass chips. Gold nanostars were grafted on properly functionalized glasses by means of electrostatic interactions and then they were coated with a silica layer of controllable thickness in the nanometer range. The SERS activity of the obtained substrates were tested in terms of reproducibility and homogeneity intra-samples and inter-samples from different batches using the Raman reporter as the model compound rhodamine 6G. The uncoated substrates were used as reference to evaluate the effect of silica spacers on SERS enhancement factors (EFs). The chemical route to obtain silica-coated SERS chips is described in detail, and the morphology and the optical response of substrates have been characterized. We demonstrate that SERS substrates coated with 1 nm silica conserve a good EF, and that the coating confers to the SERS platform an extreme robustness leading to reusability of the substrates.

Tailored coating of gold nanostars: rational approach to prototype of theranostic device based on SERS and photothermal effects at ultralow irradiance.

The last decade has come across an increasing demand for theranostic biocompatible nanodevices possessing the double ability of diagnosis and therapy. In this work, we report the design, synthesis and step-by-step characterization of rationally coated gold nanostars (GNSs) for the SERS imaging and photothermal therapy of HeLa cancer cells. The nanodevices were realized by synthesizing GNSs with a seed growth approach, coating them with a controlled mixture of thiols composed of a Raman reporter and a polyethylene glycol with a terminal amino group, and then reacting these amino groups with folic acid (FA), in order to impart selectivity towards cancer cells which overexpress folate receptors on their membranes. After a complete characterization, we demonstrate that these FA-functionalized GNSs (FA-GNSs) are able to bind selectively to the membranes of HeLa cells, acting as SERS tags and allowing SERS imaging. Moreover, we demonstrate that once bound to HeLa cell membranes, FA-GNSs exhibit photothermal effect which can be exploited to kill the same cells in vitro using laser irradiation in the NIR at a very low and safe irradiance. We thus demonstrate that the FA-GNSs designed following the described approach are an efficient prototype of theranostic nanodevices.

Tunable coating of gold nanostars: tailoring robust SERS labels for cell imaging.

Surface modification of noble metal nanoparticles with mixed molecular monolayers is one of the most powerful tools in nanotechnology, and is used to impart and tune new complex surface properties. In imaging techniques based on surface enhanced Raman spectroscopy (SERS), precise and controllable surface modifications are needed to carefully design reproducible, robust and adjustable SERS nanoprobes. We report here the attainment of SERS labels based on gold nanostars (GNSs) coated with a mixed monolayer composed of a poly ethylene glycol (PEG) thiol (neutral or negatively charged) that ensure stability in biological environments, and of a signalling unit 7-Mercapto-4-methylcoumarin as a Raman reporter molecule. The composition of the coating mixture is precisely controlled using an original method, allowing the modulation of the SERS intensity and ensuring overall nanoprobe stability. The further addition of a positively charged layer of poly (allylamine hydrocloride) on the surface of negatively charged SERS labels does not change the SERS response, but it promotes the penetration of GNSs in SH-SY5Y neuroblastoma cells. As an example of an application of such an approach, we demonstrate here the internalization of these new labels by means of visualization of cell morphology obtained with SERS mapping.

[Unidentified bright objects and neuropsychiatric disturbances]. / Unidentified bright objects: evoluzione neuroradiologica delle lesioni e correlazioni neuropsichiatriche in pazienti pediatrici affetti da neurofibromatosi tipo 1.

AIM: The neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous disease. In 40-70% of cases are described signal hyperintensity on MRI, called unidentified bright objects (UBO). Their correlation with clinical disorders is still debated. The present study investigated the correlation between the UBOs and neuropsychiatric outcomes overall, observes the long-term through the comparison of MRI brain and considers the utility of including MRI early in the investigation of NF1. METHODS: We included 100 patients (age 2-18 years) with NF1. The parents were given a medical questionnaire to fill, a clinical neurologic examination (Touwen) was performed and brain MRI were analyzed during the years. RESULTS: In 72% of cases were detected UBO's last MRI. It was observed that the UBO's tend to shrink over time and in some cases to disappear in pre-adolescent. There were significant correlations between UBOs and minor disturbances in motor function (P=0.004) and between UBO's and cognitive deficits (P=0.016). The 79.62% of the patients is followed by a specialist in neuropsychiatry, as correlated significantly (P=0.027) with changes on MRI. CONCLUSIONS: Given the correlation between UBO's, neurological disorders, cognitive and behavioral, suggest be included in the diagnostic protocol MRI brain areas as T2H can be considered predictive for a neuropsychiatric disorder.

Learning disabilities: case study of the Piedmont Region in the years 2006-2007-2008.

AIM: The aim of the study is to analyse the comorbidity of learning disabilities (LD), its variation relating to the age of the children and to interpret the possible meaning of these data. METHODS: All patients in age of compulsory education (aged 5-16) diagnosed as LD in Piedmont, registered in the Regional Informative System NPI.net, in the years 2006-2007-2008, were considered. The cases were divided in two age ranges: from 5 to 11 years the first one, from 12 to 16 years the second one. The cases were further subdivided according to comorbidity with 5 diagnostic categories, identifying: Pure LD; 2) LD + psychiatric disorders; 3) LD + psycho-developmental risk; 4) LD + not psychiatric disease; 5) LD + borderline intellectual functioning and mental retardation. The average values computed for each group of comorbidity in the three years for the two age ranges were statistically compared. RESULTS: A major number of LD was observed in the age range 12-16; here LD is more often associated to psychiatric disorders and psycho-developmental risk. LD is more often pure from 5 to11 years. CONCLUSION: LD may be an inducing factor for psychiatric pathologies and situations of psychodevelopmental risk. However the major amount of LD in the age range 12-16 may be due to the rising of psycho-developmental risk factors and of social-environmental disadvantage; so these data may underline a form of "adolescence uneasiness", evident in school, in patients without major neurologic, psychiatric and cognitive disorders. The available data collection system facilitated this study.

["Child health from birth to adolescence", a booklet issued by the Region of Piedmont. A study on the 1st year of life of 1,000 neonates]. / Il libretto della Regione Piemonte "La salute del bambino dalla nascita all'adolescenza". Indagine sul primo anno di vita di 1.000 neonati.

An investigation has been carried out on the use by parents during the first year of life of the booklet "Child health from birth to adolescence" published by the Region of Piedmont as part of a programme of preventive medicine of infancy and health education. The research was based on a questionnaire submitted to parents of 1,000 newborns, representative of the population of Turin. The results provide useful information about the development of the child and about the parent-child relationship and also on the utilisation and the utility of the booklet. The investigation also provided invaluable suggestions about modifications required in the booklet in the interests of regional programmes of preventive medicine in infancy.

Galactosylated poly(L-lysine) as a hepatotropic carrier of 9-beta-D-arabinofuranosyladenine 5'-monophosphate.

D-Galactopyranosyl residues were coupled to poly(L-lysine) and the antiviral agents arabinofuranosyladenine 5'-monophosphate (ara-AMP) and acyclovir were conjugated with this glycosylated polymer. In mice the ara-AMP conjugate accomplished a selective drug delivery to liver cells.

Drug targeting in antiviral chemotherapy. A chemically stable conjugate of 9-beta-D-arabinofuranosyl-adenine 5'-monophosphate with lactosaminated albumin accomplishes a selective delivery of the drug to liver cells.

With the aim of improving the chemotherapeutic index of 9-beta-D-arabinofuranosyl-adenine 5' monophosphate (ara-AMP) in the treatment of chronic hepatitis B, this drug was conjugated with lactosaminated serum albumin (L-SA), a neoglycoprotein which only enters into hepatocytes. We used a L-SA-ara-AMP conjugate which, in contrast to those previously employed, has the advantage of remaining soluble after lyophilization. We found in mice that: (I) this new conjugate was quite stable in the bloodstream where only a small part of ara-AMP was released; (II) after administration of the conjugate labelled in the drug moiety both acid insoluble and soluble radioactivities were several times higher in liver than in other organs; (III) in mice with Ectromelia virus hepatitis, the conjugate inhibited virus DNA synthesis in liver without affecting cellular DNA synthesis in intestine and bone marrow; (IV) the conjugate did not display any recognizable sign of acute toxicity even at doses several fold higher than those pharmacologically active; and (V) when prepared with homologous albumin it was not immunogenic.

A study on the pharmacokinetics in mouse of adenine-9-beta-D-arabinofuranoside 5-monophosphate conjugated with lactosaminated albumin.

In plasma of mice injected with adenine-9-beta-D-arabinofuranoside monophosphate (ara-AMP) coupled to human lactosaminated serum albumin (L-HSA) some of the ara-AMP molecules are enzymatically released, whereas others remain linked to L-HSA. Evidence has been obtained that ara-AMP is not deaminated when it is conjugated to L-HSA, in contrast to the free drug which is rapidly metabolized to its hypoxanthine derivative.