Latest PUBLICATIONS

  • Thyroid incidentaloma identified by ¹⁸F-fluorodeoxyglucose positron emission tomography with CT (FDG-PET/CT): clinical and pathological relevance.
    Publication Date: 01/10/2011, on Clinical endocrinology
    by Pagano L, Samà MT, Morani F, Prodam F, Rudoni M, Boldorini R, Valente G, Marzullo P, Baldelli R, Appetecchia M, Isidoro C, Aimaretti G
    DOI: 10.1111/j.1365-2265.2011.04107.x

    The percentage of patients with thyroid cancer incidentally diagnosed during a (18) F-fluorodeoxyglucose Positron Emission Tomography with computed tomography (CT) (FDG-PET/CT) for nonthyroid diseases ranges between 26% and 50%.

  • Betaines in fruits of Citrus genus plants.
    Publication Date: 14/09/2011, on Journal of agricultural and food chemistry
    by Servillo L, Giovane A, Balestrieri ML, Bata-Csere A, Cautela D, Castaldo D
    DOI: 10.1021/jf2014815

    Numerous compounds, many of them osmolytes, were quantified in natural juices and in frozen concentrate juices from fruits of plants of the Citrus genus. L-proline, N-methyl-L-proline (hygric acid), N,N-dimethyl-L-proline (stachydrine), 4-hydroxy-L-prolinebetaine (betonicine), 4-hydroxy-L-proline, γ-aminobutyric acid (Gaba), 3-carboxypropyltrimethylammonium (GabaBet), N-methylnicotinic acid (trigonelline), and choline in the fruit juices of yellow orange, blood orange, lemon, mandarin, bitter orange (Citrus aurantium), chinotto (Citrus myrtifolia), and grapefruit were analyzed by sensitive HPLC-ESI-tandem mass spectrometry procedure. It was found that the most represented osmolytes in the juices, that is, L-proline, stachydrine, and betonicine, can be quantified with minimal sample preparation and short analysis time (about 1 min) also by flow injection analysis (FIA) ESI-MS/MS with the same results as obtained by HPLC ESI-MS/MS. In all of the juices, discrete amounts of choline and trigonelline were present. Conversely, GabaBet was always below detection limits. Notably, N-methyl-L-proline and 4-hydroxy-L-prolinebetaine, which were discovered for the first time in the juice of bergamot (Citrus bergamia Risso et Poit), are also present in all of the citrus juices examined.

  • Thrombin-aptamer recognition: a revealed ambiguity.
    Publication Date: 01/09/2011, on Nucleic acids research
    by Russo Krauss I, Merlino A, Giancola C, Randazzo A, Mazzarella L, Sica F
    DOI: 10.1093/nar/gkr522

    Aptamers are structured oligonucleotides that recognize molecular targets and can function as direct protein inhibitors. The best-known example is the thrombin-binding aptamer, TBA, a single-stranded 15-mer DNA that inhibits the activity of thrombin, the key enzyme of coagulation cascade. TBA folds as a G-quadruplex structure, as proved by its NMR structure. The X-ray structure of the complex between TBA and human α-thrombin was solved at 2.9-Å resolution, but did not provide details of the aptamer conformation and the interactions with the protein molecule. TBA is rapidly processed by nucleases. To improve the properties of TBA, a number of modified analogs have been produced. In particular, a modified TBA containing a 5'-5' polarity inversion site, mTBA, has higher stability and higher affinity toward thrombin with respect to TBA, although it has a lower inhibitory activity. We present the crystal structure of the thrombin-mTBA complex at 2.15-Å resolution; the resulting model eventually provides a clear picture of thrombin-aptamers interaction, and also highlights the structural bases of the different properties of TBA and mTBA. Our findings open the way for a rational design of modified aptamers with improved potency as anticoagulant drugs.

  • Binding properties of human telomeric quadruplex multimers: a new route for drug design.
    Publication Date: 01/09/2011, on Biochimie
    by Cummaro A, Fotticchia I, Franceschin M, Giancola C, Petraccone L
    DOI: 10.1016/j.biochi.2011.04.005

    Human telomeric G-quadruplex structures are known to be promising targets for an anticancer therapy. In the past decade, several research groups have been focused on the design of new ligands trying to optimize the interactions between these small molecules and the G-quadruplex motif. In most of these studies, the target structures were the single quadruplex units formed by short human DNA telomeric sequences (typically 21-26 nt). However, the 3'-terminal single-stranded human telomeric DNA is actually 100-200 bases long and can form higher-order structures by clustering several consecutive quadruplex units (multimers). Despite the increasing number of structural information on longer DNA telomeric sequences, very few data are available on the binding properties of these sequences compared with the shorter DNA telomeric sequences. In this paper we use a combination of spectroscopic (CD, UV and fluorescence) and calorimetric techniques (ITC) to compare the binding properties of the (TTAGGG)(8)TT structure formed by two adjacent quadruplex units with the binding properties of the (AG(3)TT)(4) single quadruplex structure. The three side-chained triazatruxene derivative azatrux and TMPyP4 cationic porphyrin were used as quadruplex ligands. We found that, depending on the drug, the number of binding sites per quadruplex unit available in the multimer structure was smaller or greater than the one expected on the basis of the results obtained from individual quadruplex binding studies. This work suggests that the quadruplex units along a multimer structure do not behave as completely independent. The presence of adjacent quadruplexes results in a diverse binding ability not predictable from single quadruplex binding studies. The existence of quadruplex-quadruplex interfaces in the full length telomeric overhang may provide an advantageous factor in drug design to enhance both affinity and selectivity for DNA telomeric quadruplexes.

  • Cross-talk between cell cycle induction and mitochondrial dysfunction during oxidative stress and nerve growth factor withdrawal in differentiated PC12 cells.
    Publication Date: 01/08/2011, on Journal of neuroscience research
    by Bianco MR, Berbenni M, Amara F, Viggiani S, Fragni M, Galimberti V, Colombo D, Cirillo G, Papa M, Alberghina L, Colangelo AM
    DOI: 10.1002/jnr.22665

    Neuronal death has been reported to involve mitochondrial dysfunction and cell cycle reentry. In this report, we used Nerve Growth Factor (NGF)-differentiated PC12 cells to investigate mechanisms linking mitochondrial dysfunction and cell cycle activation during neuronal death induced by NGF withdrawal and/or oxidative stress. We found that loss of survival following H(2) O(2) -induced oxidative stress or NGF deprivation was preceded by a decrease in mitochondrial membrane potential (ΔΨm), increase in reactive oxygen species (ROS), and up-regulation of cyclin D1 and phosphorylation (Ser-780) of protein retinoblastoma (P-pRb), without an increase of proliferation rates. Treatment with H(2) O(2) , but not NGF deprivation, also induced the phosporylation (Ser-10) of p27(kip1) and the appearance of a cleaved P-p27(kip1) fragment of about 15 kDa. The extent of cell cycle activation appeared to be inversely correlated to the duration of toxic stimuli (pulse/continuous). H(2) O(2) -induced mitogenic responses appeared to be mediated by induction of P-MAPK and P-Akt and were blocked by p38MAPK and JNK inhibitors as well as by the CDK inhibitor flavopiridol (Flav) and by sodium selenite (Sel), a component of selenoproteins, including glutathione peroxidases. Inhibition of p38MAPK and JNK, instead, did not affect cyclin D1 changes following NGF deprivation. Finally, both Flav hydrochloride and Sel partially prevented mitochondrial dysfunction and cell death following NGF withdrawal or H(2) O(2) toxicity, but not during oxidative stress in the absence of NGF. Taken together, these data suggest that H(2) O(2) -induced oxidative stress can determine distinct patterns of mitogenic responses as a function of mitochondrial dysfunction depending on 1) intensity/duration of stress stimuli and/or 2) presence of NGF.

  • The triazatruxene derivative azatrux binds to the parallel form of the human telomeric G-quadruplex under molecular crowding conditions: biophysical and molecular modeling studies.
    Publication Date: 01/08/2011, on Biochimie
    by Petraccone L, Fotticchia I, Cummaro A, Pagano B, Ginnari-Satriani L, Haider S, Randazzo A, Novellino E, Neidle S, Giancola C
    DOI: 10.1016/j.biochi.2011.05.017

    The present study has employed a combination of spectroscopic, calorimetric and computational methods to explore the binding of the three side-chained triazatruxene derivative, termed azatrux, to a human telomeric G-quadruplex sequence, under conditions of molecular crowding. The binding of azatrux to the tetramolecular parallel [d(TGGGGT)](4) quadruplex in the presence and absence of crowding conditions, was also characterized. The data indicate that azatrux binds in an end-stacking mode to the parallel G-quadruplex scaffold and highlights the key structural elements involved in the binding. The selectivity of azatrux for the human telomeric G-quadruplex relative to another biologically relevant G-quadruplex (c-Kit87up) and to duplex DNA was also investigated under molecular crowding conditions, showing that azatrux has good selectivity for the human telomeric G-quadruplex over the other investigated DNA structures.

  • Evaluation of Italian patients with leber congenital amaurosis due to AIPL1 mutations highlights the potential applicability of gene therapy.
    Publication Date: 29/07/2011, on Investigative ophthalmology & visual science
    by Testa F, Surace EM, Rossi S, Marrocco E, Gargiulo A, Di Iorio V, Ziviello C, Nesti A, Fecarotta S, Bacci ML, Giunti M, Della Corte M, Banfi S, Auricchio A, Simonelli F
    DOI: 10.1167/iovs.10-6543

    To evaluate the suitability of gene delivery-based approaches as potential treatment of Leber congenital amaurosis 4 (LCA4) due to AIPL1 mutations.

  • A new anti-infective strategy to reduce adhesion-mediated virulence in Staphylococcus aureus affecting surface proteins.
    Publication Date: 01/07/2011, on International journal of immunopathology and pharmacology
    by Artini M, Scoarughi GL, Papa R, Cellini A, Carpentieri A, Pucci P, Amoresano A, Gazzola S, Cocconcelli PS, Selan L
    DOI: 10.1177/039463201102400312

    Staphylococcus aureus is a flexible microbial pathogen frequently isolated from community-acquired and nosocomial infections. The use of indwelling medical devices is associated with a significant risk of infection by this bacterium which possesses a variety of virulence factors, including many toxins, and the ability to invade eukaryotic cells or to form biofilm on biotic and abiotic surfaces. The present study evaluates the anti-infective properties of serratiopeptidase, a secreted protein of Serratia marcescens, in impairing virulence-related staphylococcal properties, such as attachment to inert surfaces and adhesion/invasion on eukaryotic cells. SPEP seems to exert its action by modulating specific proteins. Proteomic studies performed on surface proteins extracted from SPEP-treated S. aureus cultures revealed that a number of proteins are affected by the treatment. Among these we found the adhesin/autolysin Atl, FnBP-A, SecA1, Sbi, EF-Tu, EF-G, and alpha-enolase. EF-Tu, EF-G and alpha-enolase are known to perform a variety of functions, depending on their cytoplasmic or surface localization. All these factors can facilitate bacterial colonization, persistence and invasion of host tissues. Our results suggest that SPEP could be developed as a potential anti-infective agent capable to hinder the entry of S. aureus into human tissues, and also impair the ability of this pathogen to form biofilm on prostheses, catheters and medical devices.

  • AAV-mediated photoreceptor transduction of the pig cone-enriched retina.
    Publication Date: 01/07/2011, on Gene therapy
    by Mussolino C, della Corte M, Rossi S, Viola F, Di Vicino U, Marrocco E, Neglia S, Doria M, Testa F, Giovannoni R, Crasta M, Giunti M, Villani E, Lavitrano M, Bacci ML, Ratiglia R, Simonelli F, Auricchio A, Surace EM
    DOI: 10.1038/gt.2011.3

    Recent success in clinical trials supports the use of adeno-associated viral (AAV) vectors for gene therapy of retinal diseases caused by defects in the retinal pigment epithelium (RPE). In contrast, evidence of the efficacy of AAV-mediated gene transfer to retinal photoreceptors, the major site of inherited retinal diseases, is less robust. In addition, although AAV-mediated RPE transduction appears efficient, independently of the serotype used and species treated, AAV-mediated photoreceptor gene transfer has not been systematically investigated thus so far in large animal models, which also may allow identifying relevant species-specific differences in AAV-mediated retinal transduction. In the present study, we used the porcine retina, which has a high cone/rod ratio. This feature allows to properly evaluate both cone and rod photoreceptors transduction and compare the transduction characteristics of AAV2/5 and 2/8, the two most efficient AAV vector serotypes for photoreceptor targeting. Here we show that AAV2/5 and 2/8 transduces both RPE and photoreceptors. AAV2/8 infects and transduces photoreceptor more efficiently than AAV2/5, similarly to what we have observed in the murine retina. The use of the photoreceptor-specific rhodopsin promoter restricts transgene expression to porcine rods and cones, and results in photoreceptor transduction levels similar to those obtained with the ubiquitous promoters tested. Finally, immunological, toxicological and biodistribution studies support the safety of AAV subretinal administration to the large porcine retina. The data presented here on AAV-mediated transduction of the cone-enriched porcine retina may affect the development of gene-based therapies for rare and common severe photoreceptor diseases.

  • Btk regulation in human and mouse B cells via protein kinase C phosphorylation of IBtkγ.
    Publication Date: 16/06/2011, on Blood
    by Janda E, Palmieri C, Pisano A, Pontoriero M, Iaccino E, Falcone C, Fiume G, Gaspari M, Nevolo M, Di Salle E, Rossi A, De Laurentiis A, Greco A, Di Napoli D, Verheij E, Britti D, Lavecchia L, Quinto I, Scala G
    DOI: 10.1182/blood-2010-09-308080

    The inhibitor of Bruton tyrosine kinase γ (IBtkγ) is a negative regulator of the Bruton tyrosine kinase (Btk), which plays a major role in B-cell differentiation; however, the mechanisms of IBtkγ-mediated regulation of Btk are unknown. Here we report that B-cell receptor (BCR) triggering caused serine-phosphorylation of IBtkγ at protein kinase C consensus sites and dissociation from Btk. By liquid chromatography and mass-mass spectrometry and functional analysis, we identified IBtkγ-S87 and -S90 as the critical amino acid residues that regulate the IBtkγ binding affinity to Btk. Consistently, the mutants IBtkγ carrying S87A and S90A mutations bound constitutively to Btk and down-regulated Ca(2+) fluxes and NF-κB activation on BCR triggering. Accordingly, spleen B cells from Ibtkγ(-/-) mice showed an increased activation of Btk, as evaluated by Y551-phosphorylation and sustained Ca(2+) mobilization on BCR engagement. These findings identify a novel pathway of Btk regulation via protein kinase C phosphorylation of IBtkγ.

  • The human visual cortex responds to gene therapy-mediated recovery of retinal function.
    Publication Date: 01/06/2011, on The Journal of clinical investigation
    by Ashtari M, Cyckowski LL, Monroe JF, Marshall KA, Chung DC, Auricchio A, Simonelli F, Leroy BP, Maguire AM, Shindler KS, Bennett J
    DOI: 10.1172/JCI57377

    Leber congenital amaurosis (LCA) is a rare degenerative eye disease, linked to mutations in at least 14 genes. A recent gene therapy trial in patients with LCA2, who have mutations in RPE65, demonstrated that subretinal injection of an adeno-associated virus (AAV) carrying the normal cDNA of that gene (AAV2-hRPE65v2) could markedly improve vision. However, it remains unclear how the visual cortex responds to recovery of retinal function after prolonged sensory deprivation. Here, 3 of the gene therapy trial subjects, treated at ages 8, 9, and 35 years, underwent functional MRI within 2 years of unilateral injection of AAV2-hRPE65v2. All subjects showed increased cortical activation in response to high- and medium-contrast stimuli after exposure to the treated compared with the untreated eye. Furthermore, we observed a correlation between the visual field maps and the distribution of cortical activations for the treated eyes. These data suggest that despite severe and long-term visual impairment, treated LCA2 patients have intact and responsive visual pathways. In addition, these data suggest that gene therapy resulted in not only sustained and improved visual ability, but also enhanced contrast sensitivity.

  • Percutaneous radiofrequency ablation of hepatocellular carcinoma compared to percutaneous ethanol injection in treatment of cirrhotic patients: an Italian randomized controlled trial.
    Publication Date: 01/06/2011, on Anticancer research
    by Giorgio A, Di Sarno A, De Stefano G, Scognamiglio U, Farella N, Mariniello A, Esposito V, Coppola C, Giorgio V
    DOI:

    To compare 5-year survival of patients with a single hepatocellular carcinoma≤3 cm randomly assigned to receive percutaneous ethanol injection or radiofrequency ablation.

  • An atypical form of Bietti crystalline dystrophy.
    Publication Date: 01/06/2011, on Ophthalmic genetics
    by Rossi S, Testa F, Li A, Iorio VD, Zhang J, Gesualdo C, Corte MD, Chan CC, Fielding Hejtmancik J, Simonelli F
    DOI: 10.3109/13816810.2011.559653

    To describe clinical and functional features of a patient with Bietti crystalline dystrophy and atypical electroretinogram responses.

  • Interictal cortical reorganization in episodic migraine without aura: an event-related fMRI study during parametric trigeminal nociceptive stimulation.
    Publication Date: 01/05/2011, on Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology
    by Tessitore A, Russo A, Esposito F, Giordano A, Taglialatela G, De Micco R, Cirillo M, Conte F, d'Onofrio F, Cirillo S, Tedeschi G
    DOI: 10.1007/s10072-011-0537-0

    The aim of our study was to explore the pain processing network in patients with migraine during trigeminal nociceptive stimulation. Sixteen patients with episodic migraine without aura and 16 healthy controls performed functional magnetic resonance imaging during thermal stimuli (at 41, 51 and 53°C). Patients with migraine showed a greater activation in the perigenual part of anterior cingulate cortex at 51°C and less activation in the bilateral somatosensory cortex at 53°C compared to healthy controls. There were no differences in experimental pain perception between groups. Our findings demonstrate a functional reorganization of cerebral areas known to be involved in pain processing in patients with migraine.

  • Polymerization of hemoglobins in Arctic fish: Lycodes reticulatus and Gadus morhua.
    Publication Date: 01/05/2011, on IUBMB life
    by Riccio A, Mangiapia G, Giordano D, Flagiello A, Tedesco R, Bruno S, Vergara A, Mazzarella L, di Prisco G, Pucci P, Paduano L, Verde C
    DOI: 10.1002/iub.450

    In vitro, and possibly in vivo, hemoglobin polymerization and red blood cell sickling appear to be widespread in codfish. In this article, we show that the hemoglobins of the two Arctic fish Lycodes reticulatus and Gadus morhua also have the tendency to polymerize, as monitored by dynamic light scattering experiments. The elucidation of the primary structure of the single hemoglobin of the zoarcid L. reticulatus shows the presence of a large number of cysteyl residues in α and β chains. Their role in eliciting the ability to produce polymers was also addressed by MALDI-TOF and TOF-TOF mass spectrometry. The G.morhua globins are also rich in Cys, but unlike in L. reticulatus, polymerization does not seem to be disulfide driven. The widespread occurrence of the polymerization phenomenon displayed by hemoglobins of Arctic fish supports the hypothesis that this feature may bea response to stressful environmental conditions.