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  • Authors: 
    Alberto Morganti; Marco Giussani; Carla Sala; Gabriella Gazzano; Ivana Marana; Alberto Pierini; Maria Teresa Savoia; Francesca Ghio; Annalisa Cogo; Alberto Zanchetti;

    Objective To assess whether the hypoxia associated with exposure to high altitude affects plasma endothelin-1 levels, and whether changes in endothelin-1 are related to those in systemic and pulmonary blood pressure. Design Eight normal subjects ascended Mount Everest to an altitude of 5050 m within a period of 8 days (study 1) and 10 ascended Mount Rosa in the Italian Alps to an altitude of 4559 m within 2 days (study 2). In study 1 systemic blood pressure, heart rate, haematocrit, haemoglobin oxygen saturation (evaluated by percutaneous oximetry) and venous plasma endothelin-1 were measured several times during the ascent, and twice more during the time spent at high altitude. In study 2 the same parameters as well as systolic pulmonary pressure by echocardiography were evaluated on the second day of resting at 4559 m. In both studies, data obtained during the expeditions were compared with those collected from the same subjects at sea level. Results In study 1 plasma endothelin-1 increased progressively up to 4240 m (from 1.8 +/- 0.1 pg/ml at sea level to 2.7 +/- 0.2 pg/ml) and decreased slightly thereafter; these increments were directly related to the decrements in percutaneous oxygen saturation, which, at that altitude, fell from 98.6 +/- 0.2% at sea level to 80.8 +/- 0.4%. Blood pressure and haematocrit also rose in response to exposure to high altitude but these changes were not related to changes in endothelin-1. In study 2 the increments in plasma endothelin-1 were similar to those observed in study 1 and the changes again correlated with changes in oxygen saturation as well as with those in systolic pulmonary pressure. On average, systolic pulmonary pressure increased from 19 +/- 1 to 26 +/- 1.9 mmHg, whereas systemic blood pressure and haematocrit were unchanged. Conclusion Exposure to high altitude is associated with consistent increases in plasma endothelin-1. This is probably the result of augmented secretion of the peptide in response to hypoxia and may contribute to the physiological adaptation of the pulmonary circulation to this condition.

  • Publication . Other literature type . Article . 2005
    Open Access
    Rikkert L. Snoeckx; Patrick L. M. Huygen; Delphine Feldmann; Sandrine Marlin; Françoise Denoyelle; Jaroslaw Waligora; Małgorzata Mueller-Malesińska; Agneszka Pollak; Rafał Płoski; Alessandra Murgia; +54 more
    Countries: Belgium, Netherlands
    Project: NIH | Non-Syndromic Hearing Los... (5R01DC002842-21)

    Hearing impairment (HI) affects 1 in 650 newborns, which makes it the most common congenital sensory impairment. Despite extraordinary genetic heterogeneity, mutations in one gene, GJB2, which encodes the connexin 26 protein and is involved in inner ear homeostasis, are found in up to 50% of patients with autosomal recessive nonsyndromic hearing loss. Because of the high frequency of GJB2 mutations, mutation analysis of this gene is widely available as a diagnostic test. In this study, we assessed the association between genotype and degree of hearing loss in persons with HI and biallelic GJB2 mutations. We performed cross-sectional analyses of GJB2 genotype and audiometric data from 1,531 persons, from 16 different countries, with autosomal recessive, mild-to-profound nonsyndromic HI. The median age of all participants was 8 years; 90% of persons were within the age range of 0-26 years. Of the 83 different mutations identified, 47 were classified as nontruncating, and 36 as truncating. A total of 153 different genotypes were found, of which 56 were homozygous truncating (T/T), 30 were homozygous nontruncating (NT/NT), and 67 were compound heterozygous truncating/nontruncating (T/NT). The degree of HI associated with biallelic truncating mutations was significantly more severe than the HI associated with biallelic nontruncating mutations (P<.0001). The HI of 48 different genotypes was less severe than that of 35delG homozygotes. Several common mutations (M34T, V37I, and L90P) were associated with mild-to-moderate HI (median 25-40 dB). Two genotypes--35delG/R143W (median 105 dB) and 35delG/dela(GJB6-D13S1830) (median 108 dB)--had significantly more-severe HI than that of 35delG homozygotes.

  • Publication . Article . Preprint . 1997 . Embargo End Date: 01 Jan 1997
    Open Access
    G. L. Fogli; Eligio Lisi; D. Montanino; G. Scioscia;
    Publisher: arXiv
    Country: Italy

    The present possible evidences in favor of neutrino masses and mixings from solar, atmospheric, and accelerator experiments cannot be all reconciled in a three-family framework, unless some data are excluded. We grade all possible three-family scenarios according to their compatibility with the available data. A recently proposed scenario appears to emerge naturally as the most likely solution to all oscillation evidences, with the only exception of the angular dependence of multi-GeV atmospheric data in the Kamiokande experiment. We describe in detail the status and the phenomenological implications of this ``minimum sacrifice'' solution. Comment: 16 pages (RevTeX) + 3 figures (postscript); requires epsfig.sty

  • Open Access English
    Valentina Amodeo; Mariangela Marrelli; Veronica Pontieri; Roberta Cassano; Sonia Trombino; Filomena Conforti; Giancarlo Statti;
    Publisher: MDPI AG

    Spontaneous edible plants have an old history of use in popular traditions all around the world, and the rediscovery of these species could also be useful for the search of new drugs. Chenopodium album L. (Amaranthaceae) and Sisymbrium officinale (L.) Scop. (Brassicaceae) are two annual plants traditionally used both as food and herbal remedies against inflammatory disorders. In this work, the potential anti-inflammatory and anti-arthritic activities of these plant species have been investigated, together with their antioxidant potential. The phytochemical composition was assessed as well by means of gas chromatography coupled to mass spectrometry (GC-MS) and high performance thin layer chromatography (HPTLC). The antioxidant properties were assessed using the DPPH and &beta -carotene bleaching test. The ability of extracts to protect against lipid peroxidation was also examined in rat-liver microsomal membranes. All the samples showed a preservation of antioxidant activity up to 60 min. A significant inhibitory activity on the production of the pro-inflammatory mediator nitric oxide was induced in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells by the dichloromethane fraction of C. album extract, with an IC50 value equal to 81.7 ± g/mL), even if the best in vitro anti-arthritic activity was observed for the dichloromethane fraction of S. officinale extract, with an IC50 value of 680.9 ± g/mL. The same sample showed also a concentration-dependent anti-denaturation effect on heat-treated bovine serum albumin (IC50 = 975.6 ± 13.2 &mu 5.5 &mu 0.9 &mu g/mL.

  • Open Access
    Costa, M;
    Publisher: Frontiers Media SA
    Country: Italy

    The spatial aggregation/dispersion of the vegetation in a landscape affects landscape texture, with potentially important implications for its perception. The aim of the study was to investigate how plant dispersion and interspersion in small-scale landscapes could affect garden preference. Dispersion referred to the proximity and distance between plants, and interspersion referred to the degree of intermixing between plants of different species. Fifty-six participants evaluated 40 pairs of landscapes that differed in terms of plant dispersion or plant interspersion. Participants were asked to rate their preference for each pair of landscapes. Furthermore, eye movements were recorded during the viewing time, and the number of fixations and fixation time were computed for each landscape image. Overall, plants arranged in a more dispersed and a more interspersed design resulted in a higher landscape preference. Dispersion was more effective than interspersion in affecting landscape preference. The number of fixations and fixation time were higher when viewing landscapes with plants arranged in a high-dispersion and high-interspersion layout.

  • Publication . Article . Other literature type . 2014
    Open Access English
    Aleksić, J.; Ansoldi, S.; Biasuzzi, B.; Paredes, J. M.; Paredes-Fortuny, X.; Persic, M.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Reinthal, R.; +138 more
    Publisher: EDP Sciences
    Countries: Spain, Italy, Spain, Spain, Croatia, Italy, Germany, Croatia, Spain, Spain ...
    Project: MZOS | Photon-atom interaction a... (098-0982931-2875), SNSF | Investigating Extragalact... (144364), MZOS | Photon-atom interaction a... (098-0982931-2875), SNSF | Investigating Extragalact... (144364)

    The pulsar wind nebula (PWN) 3C 58 is one of the historical very-high-energy (VHE; E>100 GeV) gamma-ray source candidates. It is energized by one of the highest spin-down power pulsars known (5% of Crab pulsar) and it has been compared to the Crab Nebula due to their morphological similarities. This object was previously observed by imaging atmospheric Cherenkov telescopes (Whipple, VERITAS and MAGIC), although not detected, with an upper limit of 2.4% Crab Unit (C.U.) at VHE. It was detected by Fermi-LAT with a spectrum extending beyond 100 GeV. We analyzed 81 hours of 3C 58 data taken with the MAGIC telescopes and we detected VHE gamma-ray emission with a significance of 5.7 sigma and an integral flux of 0.65% C.U. above 1 TeV. The differential energy spectrum between 400 GeV and 10 TeV is well described by a power-law function d��/dE=f_0(E/1TeV)^{-Gamma} with f_0=(2.0\pm0.4_{stat}\pm0.6_{sys})\times10^{-13}cm^{-2}s^{-1}TeV^{-1} and Gamma=2.4\pm0.2_{stat}\pm0.2_{sys}. The skymap is compatible with an unresolved source. We report the first significant detection of PWN 3C 58 at TeV energies. According to our results 3C 58 is the least luminous VHE gamma-ray PWN ever detected at VHE and the one with the lowest flux at VHE to date. We compare our results with the expectations of time-dependent models in which electrons up-scatter photon fields. The best representation favors a distance to the PWN of 2 kpc and Far Infrared (FIR) comparable to CMB photon fields. If we consider an unexpectedly high FIR density, the data can also be reproduced by models assuming a 3.2 kpc distance. A low magnetic field, far from equipartition, is required to explain the VHE data. Hadronic contribution from the hosting supernova remnant (SNR) requires unrealistic energy budget given the density of the medium, disfavoring cosmic ray acceleration in the SNR as origin of the VHE gamma-ray emission. 5 pages, 3 figures, accebted by A&A Letters

  • Open Access
    Michael Pfister; Damiano Capobianco; Blake P. Tullis; Anton Schleiss;
    Publisher: Asce-Amer Soc Civil Engineers
    Country: Switzerland

    The collection of floating woody debris at flow control structures, such as spillways and weirs, can potentially result in reduced discharge efficiency (higher upstream head for a given weir discharge). Compared to less hydraulically-efficient control structures, piano key weirs have higher discharge efficiency (lower upstream heads for a given discharge), which may increase the likelihood of woody debris collection. A systematic laboratory study was conducted to evaluate the interaction between various piano key weir geometries and woody debris types and sizes. The results of individual (noncumulative) debris tests indicated that floating debris blockage probability is highly influenced by trunk diameter and upstream head. The effects of debris accumulation on the upstream head varied with the value of the debrisfree reference upstream head condition. At lower upstream reference head values, the cumulative debris tests indicated a relative increase of the debris-associated upstream head of approximately 70%; higher upstream reference head values produced upstream head increases limited to approximately 20%.

  • Closed Access
    Alessandra Borrelli; Marziano Marziani;
    Publisher: Springer Science and Business Media LLC

    Si studiano alcuni effetti di risonanza che si presentano nell'interazione non lineare fra una radio-onda «potente» di pulsazione ω1 e una «piu debole» di pulsazione ω2 in un magnetoplasma (ionosfera). Piu precisamente, si mostra che, oltre ai ben noti fenomeni di cross e self-modulation, in condizioni particolari, si ha un notevole aumento dell'intensita delle onde di banda laterale associate a quelle interagenti e delle armoniche di pulsazione 3ω1 dell'onda «potente».

  • Publication . Conference object . Article . 2014
    Open Access English
    Richard Tarparelli; Renato Iovine; Luigi La Spada; Lucio Vegni;
    Countries: Czech Republic, Italy

    Purpose – The purpose of this paper is to contribute an analytical and numerical study of a new type of nanoshell particles operating in the visible regime. Design/methodology/approach – The structure consists of a core/shell particle, arranged in a planar array configuration, with a polymethyl methacrylate (PMMA)-graphene core and gold thin shell. Findings – By exploiting the proposed analytical model the design of a metamaterial-based sensor, operating in the optical frequency range, for the detection of tissue diseases is shown. Originality/value – Full-wave simulations confirm the capability of the proposed sensor to identify different compounds by refractive index measurement.

  • Publication . Other literature type . Article . 2010
    Open Access English
    Børge G. Nordestgaard; M. John Chapman; Kausik K. Ray; Jan Borén; Felicita Andreotti; Gerald F. Watts; Henry N. Ginsberg; Pierre Amarenco; Alberico L. Catapano; Olivier S. Descamps; +9 more
    Publisher: HAL CCSD
    Countries: Turkey, France, France, France, Netherlands, France, Croatia, Netherlands, France, France ...

    International audience; AIMS: The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies. METHODS AND RESULTS: The robust and specific association between elevated Lp(a) levels and increased cardiovascular disease (CVD)/coronary heart disease (CHD) risk, together with recent genetic findings, indicates that elevated Lp(a), like elevated LDL-cholesterol, is causally related to premature CVD/CHD. The association is continuous without a threshold or dependence on LDL- or non-HDL-cholesterol levels. Mechanistically, elevated Lp(a) levels may either induce a prothrombotic/anti-fibrinolytic effect as apolipoprotein(a) resembles both plasminogen and plasmin but has no fibrinolytic activity, or may accelerate atherosclerosis because, like LDL, the Lp(a) particle is cholesterol-rich, or both. We advise that Lp(a) be measured once, using an isoform-insensitive assay, in subjects at intermediate or high CVD/CHD risk with premature CVD, familial hypercholesterolaemia, a family history of premature CVD and/or elevated Lp(a), recurrent CVD despite statin treatment, ≥3% 10-year risk of fatal CVD according to European guidelines, and/or ≥10% 10-year risk of fatal + non-fatal CHD according to US guidelines. As a secondary priority after LDL-cholesterol reduction, we recommend a desirable level for Lp(a) <80th percentile (less than ∼50 mg/dL). Treatment should primarily be niacin 1-3 g/day, as a meta-analysis of randomized, controlled intervention trials demonstrates reduced CVD by niacin treatment. In extreme cases, LDL-apheresis is efficacious in removing Lp(a). CONCLUSION: We recommend screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk, a desirable level <50 mg/dL as a function of global cardiovascular risk, and use of niacin for Lp(a) and CVD/CHD risk reduction.

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