212 research outputs found

    Microbial-derived pirite as evidence of early diagenetic processes on a Late Holocene shoreface deposits (Sulcis Iglesiente, West Sardinia, Italy)

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    Since Roman time, SW Sardinia was a mine district and its fluorishing industrial activity lasted few decades ago. Mine activity in the district resulted in enhanced amount of sediments transported by rivers to the coast and, one of the major concern is elucidating the mineralogical background before and after industrial activity along the present-day coasts. A 3-m long core was collected in the shoreface zone, at -13–m depth below sea level and ca. 500 m far from the coastal area located on the southern-western of Sardinia (west Mediterranean, Italy). A multidisciplinary approach was followed to study the core and two samples were collected for dating purpose. 14C analysis revealed a Late Holocene age comprises between 4320 ± 30 BP (base) and 1420 ± 30 yeas BP (close to the top). Preliminary sedimentological data show that the core is composed of medium-fine grained sand, with the presence of aligned pebbles and/or shells at the base of the strata. These strata can be interpreted as the results of major storms occurred in a shoreface setting. Pervasive early diagenetic processes and sub-oxic conditions are observed as well. The preliminary geochemical results can be summarized as follows: 1) residual metal sulphides are not detected; 2) Zn and Pb carbonates can be found in samples collected close to the beaches, 3) barite and other minerals are often concentrated in the fine fraction (<63 microns). Moreover, the microscopic analysis reveals the presence of secondary pyrite that is interpreted to be of microbial origin. Thus the microbial activity most likely plays a fundamental tool in the pervasive early digenesis of the studied core. Bacterial activity and its effect on biominerals processes and sedimentological features are actually under investigation

    Chemical-physical and ecological characterisation in the environmental project of a polluted coastal area: the Bagnoli case study

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    The Bagnoli Bay (southern Tyrrhenian Sea, Naples, Italy) has been impacted for about one century by heavy anthropogenic pollution due to an important steel plant. A multidisciplinary environmental research, aimed at the reclamation of the marine contaminated area, was planned in order to evaluate, through quantitative data, the chemical-physical and ecological characteristics of marine sediments; the latter ones are strictly related to the composition and structure of benthic foraminiferal assemblages. A comprehensive statistical approach, considering all data, was attempted in order to single out the influence of pollutants on the single species distribution. The results show strong heavy metal pollution (Fe, Mn, Pb and Zn) in the vicinity of the industrial plant. Many foraminiferal species (Haynesina germanica, Miliolinella subrotunda,Quinqueloculina parvula), have a good tolerance to some trace metals while, Bulimina sublimbata, Elphidiummacellum and Miliolinella dilatata show a good tolerance to PAHs pollution

    Anthropic pressures on Nature 2000 Sites: recommendations and monitoring criteria for the pollution emergency response activities within the Orbetello lagoon

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    L’elevato valore naturalistico e socioeconomico di un Sito Natura 2000 richiede che tutte le attività antropiche che si svolgono al suo interno (es. pesca, turismo, trasporti, attività industriali, etc.) siano gestite in maniera tale da non pregiudicare le specie e gli habitat per i quali l’area è stata designata. Molti di questi Siti sono ambienti di transizione, ovvero zone che costituiscono il passaggio naturale tra terra e mare. La loro posizione di interfaccia tra questi due ambienti li rende ecosistemi unici e biologicamente molto produttivi, sede di meccanismi di regolazione dei processi interattivi della biosfera nelle due fasi, terrestre e marina. In alcuni Siti la presenza di attività antropiche diffuse e prolungate nel tempo ha portato al riscontro di stati di contaminazione elevata, fino all’inclusione di queste zone, o parti di esse, tra i Siti di bonifica di Interesse Nazionale (SIN). Il presente lavoro descrive le linee di indirizzo e le attività di monitoraggio da attuare per la salvaguardia della salute pubblica e dell’ambiente nel corso degli interventi di messa in sicurezza di emergenza predisposti nell’area lagunare antistante l’area industriale Ex Sitoco, all’interno della perimetrazione del SIN di Orbetello, incluso in un Sito di Importanza Comunitaria. Le matrici ambientali potenzialmente a rischio a causa dell’esecuzione di tali interventi sono: acqua, sedimento, biocenosi acquatiche, avifauna, uomo. È altresì importante valutare gli effetti che le ipotetiche modifiche su microscala, apportate a livello di ogni matrice, potrebbero causare nel lungo periodo su macroscala.The high naturalistic and socio-economic value of Natura 2000 sites requires that all human activities performed within their borders (e.g. fishing, tourism, transports, industrial activities) are regulated. Indeed, the site management should assure the effective safeguard of all species and habitats of European interest included in the protected area. A lot of such sites are located in transitional environments, that are areas characterised by a natural progression from the terrestrial to the water environments. Such environments include unique and very productive habitats, and they represent the regulation mechanisms of the interactive processes of the terrestrial and marine biosphere. In some sites, the presence of human activities that are distributed both in space and time has led to high levels of contamination, that in some cases even required their inclusion in Reclamation Sites of National Interest (SIN). The present study describes the planning and monitoring activities to be performed in order to safeguard human and environment health during the actions of MISE in the lagoonal area in front of the industrial area Ex Sitoco, within the borders of the Orbetello SIN, included in a SCI. The environmental parameters that are potentially at risk due to such activities are: water, sediment, water biocenosis, birds, humans. Furthermore, it is important to evaluate the effects that potential variations at the microscale level may cause at the macroscale level

    Health determinants in italian type 2 diabetes Mellitus (T2DM) patients : a critical gender differences analysis

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    Different studies described the important role of wellbeing, self-care and self-efficacy (i.e. health determinants) to achieve best health outcomes in Type 2 Diabetes Mellitus (T2DM) patients. However, literature has paid little attention to highlight the possible gender differences related to the T2DM perception of those health determinants. For these reason, the aim of this study was to describe T2DM patients' gender differences related to their wellbeing, self-care and self-efficacy. This study was performed by a secondary analysis of data from a cross-sectional research, conducted in an outpatient setting in Northern Italy. Data was collected from March 2014 and July 2016 in a cohort of 115 T2DM outpatients, aged from 60 to 91 years (mean = 69.78 \ub1 7.11). Our results showed that men perceived more general wellbeing than women, and more diabetes specific self-efficacy. No differences seemed to be related to self-care. Indeed, the stratification by gender of the bivariate analysis allowed to identify many peculiarities related to wellbeing domains and self-efficacy. This study had a pioneering nuance in Italian assessment of T2DM health determinants, and it could have a number of future implications. Further empirical researches should provide more information to deeply understand the T2DM patients' peculiarities, which could help nurses to improve a personalized care delivery

    Translocation of a Bak C-Terminus Mutant from Cytosol to Mitochondria to Mediate Cytochrome c Release: Implications for Bak and Bax Apoptotic Function

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    One of two proapoptotic Bcl-2 proteins, Bak or Bax, is required to permeabilize the mitochondrial outer membrane during apoptosis. While Bax is mostly cytosolic and translocates to mitochondria following an apoptotic stimulus, Bak is constitutively integrated within the outer membrane. Membrane anchorage occurs via a C-terminal transmembrane domain that has been studied in Bax but not in Bak, therefore what governs their distinct subcellular distribution is uncertain. In addition, whether the distinct subcellular distributions of Bak and Bax contributes to their differential regulation during apoptosis remains unclear.To gain insight into Bak and Bax targeting to mitochondria, elements of the Bak C-terminus were mutated, or swapped with those of Bax. Truncation of the C-terminal six residues (C-segment) or substitution of three basic residues within the C-segment destabilized Bak. Replacing the Bak C-segment with that from Bax rescued stability and function, but unexpectedly resulted in a semi-cytosolic protein, termed Bak/BaxCS. When in the cytosol, both Bax and Bak/BaxCS sequestered their hydrophobic transmembrane domains in their hydrophobic surface groove. Upon apoptotic signalling, Bak/BaxCS translocated to the mitochondrial outer membrane, inserted its transmembrane domain, oligomerized, and released cytochrome c. Despite this Bax-like subcellular distribution, Bak/BaxCS retained Bak-like regulation following targeting of Mcl-1.Residues in the C-segment of Bak and of Bax contribute to their distinct subcellular localizations. That a semi-cytosolic form of Bak, Bak/BaxCS, could translocate to mitochondria and release cytochrome c indicates that Bak and Bax share a conserved mode of activation. In addition, the differential regulation of Bak and Bax by Mcl-1 is predominantly independent of the initial subcellular localizations of Bak and Bax

    Exogenous Ether Lipids Predominantly Target Mitochondria

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    Ether lipids are ubiquitous constituents of cellular membranes with no discrete cell biological function assigned yet. Using fluorescent polyene-ether lipids we analyzed their intracellular distribution in living cells by microscopy. Mitochondria and the endoplasmic reticulum accumulated high amounts of ether-phosphatidylcholine and ether-phosphatidylethanolamine. Both lipids were specifically labeled using the corresponding lyso-ether lipids, which we established as supreme precursors for lipid tagging. Polyfosine, a fluorescent analogue of the anti-neoplastic ether lipid edelfosine, accumulated to mitochondria and induced morphological changes and cellular apoptosis. These data indicate that edelfosine could exert its pro-apoptotic power by targeting and damaging mitochondria and thereby inducing cellular apoptosis. In general, this study implies an important role of mitochondria in ether lipid metabolism and intracellular ether lipid trafficking

    Neutralizing antibodies explain the poor clinical response to Interferon beta in a small proportion of patients with Multiple Sclerosis: a retrospective study

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    <p>Abstract</p> <p>Background</p> <p>Neutralizing antibodies (NAbs) against Interferon beta (IFNβ) are reported to be associated with poor clinical response to therapy in multiple sclerosis (MS) patients. We aimed to quantify the contribution of NAbs to the sub-optimal response of IFNβ treatment.</p> <p>Methods</p> <p>We studied the prevalence of NAbs in MS patients grouped according to their clinical response to IFNβ during the treatment period. Patients were classified as: group A, developing ≥ 1 relapse after the first 6 months of therapy; group B, exhibiting confirmed disability progression after the first 6 months of therapy, with or without superimposed relapses; group C, presenting a stable disease course during therapy. A cytopathic effect assay tested the presence of NAbs in a cohort of ambulatory MS patients treated with one of the available IFNβ formulations for at least one year. NAbs positivity was defined as NAbs titre ≥ 20 TRU.</p> <p>Results</p> <p>Seventeen patients (12.1%) were NAbs positive. NAbs positivity correlated with poorer clinical response (<it>p </it>< 0.04). As expected, the prevalence of NAbs was significantly lower in Group C (2.1%) than in Group A (17.0%) and Group B (17.0%). However, in the groups of patients with a poor clinical response (A, B), NAbs positivity was found only in a small proportion of patients.</p> <p>Conclusion</p> <p>The majority of patients with poor clinical response are NAbs negative suggesting that NAbs explains only partially the sub-optimal response to IFNβ.</p
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