2,035 research outputs found
Isoflavones and other compounds from the roots of Iris marsica I. Ricci E Colas. Collected from Majella National Park, Italy
In this study, a phytochemical analysis was performed, for the first time, on Iris marsica I. Ricci e Colas. In particular, the attention was focused on the constituents of the roots. Twenty-one compounds were isolated by column chromatography and were analyzed/identified by NMR spectroscopy and mass spectrometry. They all own chemotaxonomic, ethno-pharmacological and nutraceutical relevance which allowed us to provide a phytochemical rationale, for the correct botanical classification of this species, for the employment of its roots in folk medicine like for all the other species belonging to the Iris genus and, lastly, for their further uses as food with important healthy benefits. All of these parts were broadly discussed about within the text
Secondary metabolites with ecologic and medicinal implications in Anthemis cretica subsp. petraea from Majella National Park
Anthemis cretica subsp. petraea (Ten.) Greuter is a plant belonging to the Asteraceae family and endemic of central Italy. In this paper, the first analysisof the ethanolic fraction of samples collected in the Majella National Park is reported. Seven compounds were isolated and identified namely parthenolide (1), 9α-acetoxyparthenolide (2), tamarixetin (3), 7-hydroxycoumarin (4), 4'-hydroxyacetophenone (5), leucanthemitol (conduritol F) (6),and proto-quercitol (7). Isolation of the compounds was achieved by means ofcolumn chromatography (CC), while their identification was achieved through spectroscopic and spectrometric techniques. The presence of these compounds is of great relevance. Compounds 1 and 2 are chemosystematic markers of the family, thus confirming the correct botanical classification of the species. Conversely, compounds 3, 5,and 7 were identified for the first time in the species and, instead, confirm the tendency of endemic entities to develop characteristic metabolite patterns in respect to cosmopolite species. Moreover, the presence of compounds 6 and 7 has ecologic implications and may be linked to this taxon’s adaption to dry environments. The production of these osmolytes may, in fact, represent the reason why this species is able to survive in extreme conditions of aridity. Lastly, from a medicinal standpoint, the isolated compounds are endowed with interesting biological activities and may justify, on a molecular base, the widespread traditional uses of the Anthemis species, as well as a basis for the use ofthe subspecies petraea
Cloaking using the anisotropic multilayer sphere
We studied a Spherically Radially Anisotropic (SRA) multilayer sphere with an arbitrary number of layers. Within each layer permittivity components are different from each other in radial and tangential directions. Under the quasi-static approximation, we developed a more generalized mathematical model that can be used to calculate polarizability of the SRA multilayer sphere with any arbitrary number of layers. Moreover, the functionality of the SRA multilayer sphere as a cloak has been investigated. It has been shown that by choosing a suitable contrast between components of the permittivity, the SRA multilayer sphere can achieve threshold required for invisibility cloaking
Dielectric permittivity of aqueous solutions of electrolytes probed by THz time-domain and FTIR spectroscopy
We have measured the dielectric permittivity of pure water and aqueous chlorides solutions in the range 0.2-1.5THz. We considered the relaxation spectral function as the weighted sum of two independent single-parameter Debye functions. Such an approach allowed to drastically reduce the number of the parameters used in the fit which we set only by physical considerations. The resulting functions allow to fit the experimental data for pure water and solutions of LiCl, KCl, NaCl, and CsCl and to predict the excess response on the high frequency side of the relaxation without “ad hoc” corrective terms
IdentitĂ e relazioni sociali. Dai popoli migranti alla cultura del Web 2.0
Nel saggio è una riflessione preliminare su cos'è da intendere per identità prima di individuare il ruolo che svolge la comunicazione non solo nel mantenere ma anche e soprattutto nel costruire identità e nel gestire relazioni, nel senso di crearle, mutarle o annullarle.The essay is a reflection about identity and role of communication on creating, mantaining and destroying social relations
Evolution of human IgH3 ' EC duplicated structures: both enhancers HS1,2 are polymorphic with variation of transcription factor's consensus sites
The enhancer complex regulatory region at the 3' of the immunoglobulin heavy cluster (IgH3'EC) is duplicated in apes along with four constant genes and the region is highly conserved throughout humans. Both human IgH3'ECs consist of three loci high sensitive (HS) to DNAse I with enhancer activity. It is thus possible that the presence of structural divergences between the two IgH3'ECs and of relative polymorphisms correspond to functional regulatory changes. To analyse the polymorphisms of these almost identical regions, it resulted mandatory to identify the presence of divergent sequences, in order to select distinctive primers for specific PCR genomic amplifications. To this aim, we first compared the two entire IgH3'ECs in silicio, utilising the updated GenBank (GB) contigs, then we analysed the two IgH3'ECs by cloning and sequencing amplicons from independent genomes. In silicio analysis showed that several inversions, deletions and short insertions had occurred after the duplication. We analysed in detail, by sequencing specific regions, the polymorphisms occurring in enhancer HS1,2-A (which lies in IgH3'EC-1, 3' to the C alpha-1 gene) and in enhancer HS1,2-B (which lies in IgH3'EC-2, 3' to C alpha-2). Polymorphisms are due to the repetition (occurring one to four times) of a 38-bp sequence present at the 3' of the core of enhancers HS1,2. The structure of both human HS1,2 enhancers has revealed not yet described polymorphic features due to the presence of variable spacer elements separating the 38-bp repetitions and to variable external elements bordering the repetition cluster. We found that one of the external elements gave rise to a divergent allele 3 in the two clusters. The frequency of the different alleles of the two loci varies in the Italian population and allele 3 of both loci are very rare. The analysis of the Callicebus moloch, Gorilla gorilla and Pan troglodytes HS1,2 enhancers showed the transformation from the ancestral structure with the 31- to the 17-by external element in hominids. The relevance of the polymorphisms in the HS1,2 enhancers is due to the variable number of binding sites for the transcription factors: NF-kappa B, CMYB, BSAP1/2, AP1/4, E47, MyoD and mu E5 and thus to the possible influence of these variations on switch, production of Ig and on maturation of B cells. (c) 2004 Elsevier B.V. All rights reserved
Metabolic reprogramming and epithelial-to-mesenchymal transition in cancer
Several lines of evidence indicate that during transformation epithelial cancer cells can acquire mesenchymal features via a process called epithelial-to-mesenchymal transition (EMT). This process endows cancer cells with increased invasive and migratory capacity, enabling tumour dissemination and metastasis. EMT is associated with a complex metabolic reprogramming, orchestrated by EMT transcription factors, which support the energy requirements of increased motility and growth in harsh environmental conditions. The discovery that mutations in metabolic genes such as FH, SDH and IDH activate EMT provided further evidence that EMT and metabolism are intertwined. In this review, we discuss the role of EMT in cancer and the underpinning metabolic reprogramming. We also put forward the hypothesis that, by altering chromatin structure and function, metabolic pathways engaged by EMT are necessary for its full activation.MS and CF are funded by an MRC Core Funding to the MRC Cancer Unit
Surgical strategies for duodenal GISTs: benefits and limitations of minimal resections
Comment on
Conservative surgery vs. duodeneopancreatectomy in primary duodenal gastrointestinal stromal tumors (GIST): a retrospective review of 114 patients from the French sarcoma group (FSG). [Eur J Surg Oncol. 2014
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