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991.
Mauro Tognon Alfredo Corallini Marco Manfrini Angelo Taronna Janet S. Butel Silvia Pietrobon Lorenzo Trevisiol Ilaria Bononi Emanuela Vaccher Giuseppe Barbanti-Brodano Fernanda Martini Elisa Mazzoni 《PloS one》2016,11(1)
Simian Virus 40, experimentally assayed in vitro in different animal and human cells and in vivo in rodents, was classified as a small DNA tumor virus. In previous studies, many groups identified Simian Virus 40 sequences in healthy individuals and cancer patients using PCR techniques, whereas others failed to detect the viral sequences in human specimens. These conflicting results prompted us to develop a novel indirect ELISA with synthetic peptides, mimicking Simian Virus 40 capsid viral protein antigens, named mimotopes. This immunologic assay allowed us to investigate the presence of serum antibodies against Simian Virus 40 and to verify whether Simian Virus 40 is circulating in humans. In this investigation two mimotopes from Simian Virus 40 large T antigen, the viral replication protein and oncoprotein, were employed to analyze for specific reactions to human sera antibodies. This indirect ELISA with synthetic peptides from Simian Virus 40 large T antigen was used to assay a new collection of serum samples from healthy subjects. This novel assay revealed that serum antibodies against Simian Virus 40 large T antigen mimotopes are detectable, at low titer, in healthy subjects aged from 18–65 years old. The overall prevalence of reactivity with the two Simian Virus 40 large T antigen peptides was 20%. This new ELISA with two mimotopes of the early viral regions is able to detect in a specific manner Simian Virus 40 large T antigen-antibody responses. 相似文献
992.
Prion diseases, or transmissible spongiform encephalopathies, have revealed the bewildering phenomenon of transmissibility in neurodegenerative diseases. Hence, the experimental transmissibility of prion-like neurodegenerative diseases via template directed misfolding has become the focus of intense research. Gerstmann-Sträussler-Scheinker disease (GSS) is an inherited prion disease associated with mutations in the prion protein gene. However, with the exception of a few GSS cases with P102L mutation characterized by co-accumulation of protease-resistant PrP core (PrPres) of ~21?kDa, attempts to transmit to rodents GSS associated to atypical misfolded prion protein with ~8 kDa PrPres have been unsuccessful. As a result, these GSS subtypes have often been considered as non-transmissible proteinopathies rather than true prion diseases. In a recent study we inoculated bank voles with GSS cases associated with P102L, A117V and F198S mutations and found that they transmitted efficiently and produced distinct pathological phenotypes, irrespective of the presence of 21?kDa PrPres in the inoculum. This study demonstrates that GSS is a genuine prion disease characterized by both transmissibility and strain variation. We discuss the implications of these findings for the understanding of the heterogeneous clinic-pathological phenotypes of GSS and of the molecular underpinnings of prion infectivity. 相似文献
993.
994.
Angelo Liguori Giovanni Sindona Nicola Uccella 《Nucleosides, nucleotides & nucleic acids》2013,32(3):373-377
Abstract The effect of benzoyl substitution on the unimolecular depurination of deoxyadenosine, in the gas-phase, has been evaluated. The glycosidic bond dissociation of the conjugated acids and bases of the isomeric species occurs remote fran the charge sites. 相似文献
995.
Massimiliano Conson Elisabetta Mazzarella Alessandro Frolli Dalila Esposito Nicoletta Marino Luigi Trojano Angelo Massagli Giovanna Gison Nellantonio Aprea Dario Grossi 《PloS one》2013,8(7)
Asperger syndrome (AS) is a neurodevelopmental condition within the Autism Spectrum Disorders (ASD) characterized by specific difficulties in social interaction, communication and behavioural control. In recent years, it has been suggested that ASD is related to a dysfunction of action simulation processes, but studies employing imitation or action observation tasks provided mixed results. Here, we addressed action simulation processes in adolescents with AS by means of a motor imagery task, the classical hand laterality task (to decide whether a rotated hand image is left or right); mental rotation of letters was also evaluated. As a specific marker of action simulation in hand rotation, we assessed the so-called biomechanical effect, that is the advantage for judging hand pictures showing physically comfortable versus physically awkward positions. We found the biomechanical effect in typically-developing participants but not in participants with AS. Overall performance on both hand laterality and letter rotation tasks, instead, did not differ in the two groups. These findings demonstrated a specific alteration of motor imagery skills in AS. We suggest that impaired mental simulation and imitation of goal-less movements in ASD could be related to shared cognitive mechanisms. 相似文献
996.
Sara Piciucchi Sara Tomassetti Gianluca Casoni Nicola Sverzellati Angelo Carloni Alessandra Dubini Giampaolo Gavelli Alberto Cavazza Marco Chilosi Venerino Poletti 《Respiratory research》2011,12(1):1-5
Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a recently described clinical-pathologic entity characterized by pleural and subpleural parenchymal fibrosis, mainly in the upper lobes. As this disease is extremely rare (only 7 cases have been described in the literature to date) poorly defined cases of IPPFE can go unrecognized. The clinical course of disease is progressive and prognosis is poor, with no therapeutic options other than lung transplantation currently available, yet. The aim of this report is to describe two further cases of this rare disease, reviewing CT, clinical and histological features. 相似文献
997.
998.
Valentina Iori Fabrizio Pietrini Angelo Massacci Massimo Zacchini 《Plant Cell, Tissue and Organ Culture》2012,108(1):17-26
Callus cultures of two parental clones of Populus nigra L., Poli and 58-861, originating from contrasting environments, were exposed to different cadmium concentrations (0, 150
and 250 μM CdSO4). Clones showed different growth responses to cadmium, evaluated by the tolerance index (Ti), with Poli being more tolerant
to the metal at both concentrations. The cadmium concentration at the end of the treatment was very similar between clones
at 150 μM CdSO4, while a higher value in 58-861 compared to Poli was detected at 250 μM CdSO4. The bioconcentration factor evidenced the lowest value in Poli at 250 μM CdSO4. Unlike 58-861, cadmium provoked a strong induction of thiols and phytochelatins in clone Poli. In both clones, organic acid
concentration differed notably in untreated calli and cadmium treatment induced a general lowering of these compounds. A notably
higher antioxidant enzyme activity (ascorbate peroxidase, APX; catalase, CAT; guaiacol peroxidase, GPX) was measured in control
calli of clone Poli compared to 58-861. Cadmium induced a remarkable enhancement of APX and CAT, but not GPX, activity at
150 μM CdSO4 in Poli. Conversely, in 58-861 at 150 μM CdSO4, and in both clones at 250 μM CdSO4, a decrease in the antioxidant activity occurred. This investigation provided evidence that these two contrasting genotypes
of P. nigra are characterised by a different response to cadmium in callus cultures. In particular, in Poli, the higher tolerance to
cadmium is associated with a higher activity of antioxidative enzymes and the ability to strongly increase thiol and PC concentration
in response to metal exposure. 相似文献
999.
Angelo Monguzzi Francesco Bianchi Alberto Bianchi Michele Mauri Roberto Simonutti Riccardo Ruffo Riccardo Tubino Francesco Meinardi 《Liver Transplantation》2013,3(5):680-686
Optically active materials able to up‐convert the frequency of the incident radiation can be used to enhance the performance of photovoltaic and photocatalityc cells, recovering sub‐bandgap photons not directly absorbed by the devices. Actually, sensitized up‐conversion (SUC) based on multi‐component organic systems is the most promising approach for these photon energy managing processes, being efficient also at the solar irradiance. However, applications of SUC on real devices have not been yet accomplished because its conversion yield usually drops dramatically in the solid state where the low dye mobility inhibits the diffusion controlled mechanisms ruling SUC photophysics. To overcome this limit, we prepared a single‐phase elastomer (poly‐butylacrilate) doped with proper dyes (platinum (II) octaetyl‐porphyrin and 9,10‐diphenylanthracene) to fabricate an efficient photon up‐converting material. Thanks to the residual molecular diffusion provided by the soft host, and to the quenching reduction of involved metastable electronic excited‐states in a solid environment compared to a liquid one, we obtained a record SUC yield of 17% at the solid state. SUC efficiency has been studied as function of the excitation power and sample temperature, elucidating the photophysical processes at the base of the high observed yield and assessing the guidelines for the fabrication of technologically appealing low power up‐converting materials. 相似文献
1000.
Angelo Rambelli 《Plant biosystems》2013,147(3):99-107