Variazioni di miRNA circolanti in casi di carcinoma mammario sottoposti a regime dietetico con oli addizionati di polifenoli

Dal 2002, quando i primi risultati relativi alla possibile associazione tra espressione di alcuni miRNA e cancro furono pubblicati, numerosi studi hanno evidenziato un intervento diretto dei miRNA nella regolazione di geni e di pathways collegati alla sviluppo tumorale. Recentemente si sta sempre pi\uf9 confermando l\u2019evidenza che cambiamenti epigenetici, alterazioni molecolari e componenti bioattivi della dieta possono genericamente modificare l'espressione genica attraverso la modulazione di specifici miRNA. Scopo principale della ricerca \ue8 la valutazione dei livelli di espressione di particolari miRNA circolanti nel sangue periferico sia di donne sane che di pazienti affette da carcinoma mammario che hanno accettato di assumere quantit\ue0 fissate di olio addizionato con polifenoli. Si \ue8 proceduto con l\u2019analisi comparata multi steps andando dal valutare comparativamente variazioni di espressioni di miRNA generalmente coinvolti in processi cancerosi al confronto di variazioni di espressione di altri miRNA associati a stati neoplastici via via sempre pi\uf9 specifici rispetto al carcinoma mammario. Questa strategia di lettura dati potrebbe suggerire varie associazioni di interesse e potr\ue0 fornire indicazioni di coinvolgimento di miRNA distinguendo fra quelli con associazioni generiche rispetto a quelli con coinvolgimenti specifici. Abbiamo utilizzato tecnologie avanzate, come il sequenziamento dell\u2019RNA e l\u2019Open array con chimica Taqman. Determinare la variazione dei livelli di miRNA nel siero dopo esposizione ad agenti dietetici potrebbe essere utilizzato come strumento diagnostico per monitorare gli effetti del trattamento nel tempo. Ricordiamo che questo studio rappresenta il primo tentativo di comparare variazioni di miRNA in vivo dopo assunzione di oli bioattivi da parte di soggetti sani e affetti da carcinoma mammario

On the Number of Cosmic Strings

The number of cosmic strings in the observable universe is relevant in determining the probability of detecting such cosmic defects through their gravitational signatures. In particular, we refer to the observation of gravitational lensing events and anisotropy in the CMB radiation induced by cosmic strings. In this paper, a simple method is adopted to obtain an approximate estimate of the number of segments of cosmic strings, crossing the particle horizon, which fall inside the observed part of the universe. We show that there is an appreciable difference in the expected number of segments which differentiates cosmic strings arising in Abelian Higgs and Nambu-Goto models, and that a different choice of setting for the cosmological model can lead to significant differences in the expected number of cosmic string segments. Of this number, the fraction realistically detectable may be considerably smaller.Comment: LaTex2e, 15 pages, 1 figure, 5 tables. Subject extended to other cosmological scenarios from Sect. 3 on hence, it follows a modification in the title; three tables and references added. Version to appear in MNRA

Identification of priority areas for plant conservation in Madagascar using Red List criteria: rare and threatened Pandanaceae indicate sites in need of protection

A major problem in establishing effective protocols for conserving Madagascar's biodiversity is the lack of reliable information for the identification of priority sites in need of protection. Analyses of field data and information from herbarium collections for members of the plant family Pandanaceae (85 spp. of Pandanus; 6 spp. of Martellidendron) showed how risk of extinction assessments can inform conservation planning. Application of IUCN Red List categories and criteria showed that 91% of the species are threatened. Mapping occurrence revealed centres of richness and rarity as well as gaps in Madagascar's existing protected area network. Protection of 10 additional sites would be required to encompass the 19 species currently lacking representation in the reserve network, within which east coast littoral forests are particularly under represented and important. The effect of scale on assessments of risk of extinction was explored by applying different grid cell sizes to estimate area of occupancy. Using a grid cell size within the range suggested by IUCN overestimates threatened status if based solely upon specimen data. For poorly inventoried countries such as Madagascar measures of range size based on such data should be complemented with field observations to determine population size, sensitivity to disturbance, and specific threats to habitat and therefore potential population decline. The analysis of such data can make an important contribution to the conservation planning process by identifying threatened species and revealing the highest priority sites for their conservatio

A new experimental snow avalanche test site at Seehore peak in Aosta Valley (NW Italian Alps) - Part II: Engineering aspects

The estimate of the effects produced by the impact of a snow avalanche against an obstacle is of the utmost importance in designing safe mountain constructions. For this purpose, an ad-hoc instrumented obstacle was designed and built in order to measure impact forces of small and medium snow avalanches at Seehore peak (NW Italian Alps). The structural design had to consider several specific and unusual demands dictated by the difficult environment. In this article, the new test facility is described from the engineering point of view, discussing the most important aspects of the analyzed problems which were solved before and after the construction. The performance of the instrumented obstacle in the first two operating seasons, and some proposals for future upgrading are eventually illustrate

PAMELA results on the cosmic-ray antiproton flux from 60 MeV to 180 GeV in kinetic energy

The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray antiproton flux and the antiproton-to-proton flux ratio which extends previously published measurements down to 60 MeV and up to 180 GeV in kinetic energy. During 850 days of data acquisition approximately 1500 antiprotons were observed. The measurements are consistent with purely secondary production of antiprotons in the galaxy. More precise secondary production models are required for a complete interpretation of the results.Comment: 11 pages, 3 figures, 1 table. Accepted for publication in Physical Review Letter

PAMELA Measurements of Cosmic-ray Proton and Helium Spectra

Protons and helium nuclei are the most abundant components of the cosmic radiation. Precise measurements of their fluxes are needed to understand the acceleration and subsequent propagation of cosmic rays in the Galaxy. We report precision measurements of the proton and helium spectra in the rigidity range 1 GV-1.2 TV performed by the satellite-borne experiment PAMELA. We find that the spectral shapes of these two species are different and cannot be well described by a single power law. These data challenge the current paradigm of cosmic-ray acceleration in supernova remnants followed by diffusive propagation in the Galaxy. More complex processes of acceleration and propagation of cosmic rays are required to explain the spectral structures observed in our data.Comment: 13 pages, 4 figures, link to SOM (with tables) in the references. This manuscript has been accepted for publication in Science. This version has not undergone final editing. Please refer to the complete version of record at http://www.sciencemag.org/ [www.sciencemag.org

The cosmic-ray electron flux measured by the PAMELA experiment between 1 and 625 GeV

Precision measurements of the electron component in the cosmic radiation provide important information about the origin and propagation of cosmic rays in the Galaxy. Here we present new results regarding negatively charged electrons between 1 and 625 GeV performed by the satellite-borne experiment PAMELA. This is the first time that cosmic-ray electrons have been identified above 50 GeV. The electron spectrum can be described with a single power law energy dependence with spectral index -3.18 +- 0.05 above the energy region influenced by the solar wind (> 30 GeV). No significant spectral features are observed and the data can be interpreted in terms of conventional diffusive propagation models. However, the data are also consistent with models including new cosmic-ray sources that could explain the rise in the positron fraction.Comment: 11 pages, 3 figures, accepted for publication in PR