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991.
Jean?Paulo?de?Andrade Raquel?B.?Giordani Laura?Torras-Claveria Natalia?Belén?Pigni Strahil?Berkov Mercè?Font-Bardia Teresa?Calvet Eduardo?Konrath Kelly?Bueno Liana?G.?Sachett Julie?H.?Dutilh Warley?de?Souza Borges Francesc?Viladomat Amelia?T.?Henriques Jerald?J.?Nair José?Angelo?S.?Zuanazzi Jaume?BastidaEmail author 《Phytochemistry Reviews》2016,15(1):147-160
Nine Brazilian Amaryllidaceae species were studied for their alkaloid composition and acetylcholinesterase (AChE) inhibitory activity via GC–MS and a modified Ellman assay, respectively. A total of thirty-six alkaloids were identified in these plants, of which Hippeastrum papilio and H. glaucescens exhibited the highest galanthamine content and the best IC50 values against AChE. Furthermore, Hippeastrum vittatum and Rhodophiala bifida also showed notable AChE inhibitory effects. X-ray crystallographic data for four galanthamine-type compounds revealed significant differences in the orientation of the N-methyl group, which are shown to be related to AChE inhibition. 相似文献
992.
993.
Paolo Ruggeri Andrea Splendiani Giulia Occhipinti Tatiana Fioravanti Alberto Santojanni Iole Leonori Andrea De Felice Enrico Arneri Gabriele Procaccini Gaetano Catanese Vjekoslav Ti?ina Angelo Bonanno Paola Nisi Cerioni Massimo Giovannotti William Stewart Grant Vincenzo Caputo Barucchi 《PloS one》2016,11(4)
The sustained exploitation of marine populations requires an understanding of a species'' adaptive seascape so that populations can track environmental changes from short- and long-term climate cycles and from human development. The analysis of the distributions of genetic markers among populations, together with correlates of life-history and environmental variability, can provide insights into the extent of adaptive variation. Here, we examined genetic variability among populations of mature European anchovies (n = 531) in the Adriatic (13 samples) and Tyrrhenian seas (2 samples) with neutral and putative non-neutral microsatellite loci. These genetic markers failed to confirm the occurrence of two anchovy species in the Adriatic Sea, as previously postulated. However, we found fine-scale population structure in the Adriatic, especially in northern areas, that was associated with four of the 13 environmental variables tested. Geographic gradients in sea temperature, salinity and dissolved oxygen appear to drive adaptive differences in spawning time and early larval development among populations. Resolving adaptive seascapes in Adriatic anchovies provides a means to understand mechanisms underpinning local adaptation and a basis for optimizing exploitation strategies for sustainable harvests. 相似文献
994.
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
995.
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
996.
997.
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
998.
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
999.
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
1000.