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1.
Chemosphere ; 306: 135509, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35787880

ABSTRACT

Boron (B) and Lithium (Li) concentrations were studied in the Platani river, one of the most important catchments of South-Central Sicily which is under semiarid climatic conditions for roughly eight months to a year. In this area, evaporites result in potential B and Li sources for surface waters. Results from river waters have measured ionic strength values between 0.1 and 4.54 M. B and Li distributions in these waters were studied in colloidal (CF, extracted by ultrafiltration from the 0.45 µm filtrate) and total dissolved (TDF) fractions and in fractions extracted from corresponding riverbed sediments, according to changes of the B/Li ratio. In river waters, CF and TDF showed very similar B/Li values, suggesting that only negligible fractionation occurs between Li and B in the aqueous phase. Similar evidence was observed between B/Li values in TDF and the labile sediment fraction, whereas an inverse relationship arose between B/Li values in TDF and in the easily reducible sediment fraction. This relationship indicates that Mn oxy-hydroxides preferentially react with aqueous B species relative to Li at the riverbed sediment interface. The extent of the B-Mn oxy-hydroxide reactions is influenced by the ionic strength, so that only B/Li values below 4 are measured in river waters with ionic strength values above 0.5 M. Comparing B/Li and ionic strength values measured in the Platani river with those from oxic brines worldwide, the same preferential B removal relative to Li is observed. This evidence suggests that B is removed as positively-charged borate ion-pairs, formed in the aqueous phase under higher ionic strength conditions, reacting with negatively charged surfaces of Mn oxy-hydroxides. The observed B reactivity relative to Li could be exploited to bring down the B excess from natural or waste waters, allowing the natural reactions with Mn oxy-hydroxides to take place under natural conditions.


Subject(s)
Rivers , Water Pollutants, Chemical , Boron , Environmental Monitoring/methods , Geologic Sediments , Lithium , Metals/analysis , Water Pollutants, Chemical/analysis
2.
Chemosphere ; 185: 268-276, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28709038

ABSTRACT

The Zr, Hf, Y and lanthanide (REE) distribution in biological tissues of Sabella spallanzanii and Styela plicata species collected from two harbours from the northern Sicily is studied for providing information regarding the Zr, Hf and REE uptake from the environment. Previous studies determined the fractionation of dissolved REE scavenged on binding sites onto biological surfaces. By comparing the recognised shale-normalised REE patterns of studied samples with evidence from reference data, the observed behaviour of these elements in biological tissues of Sabella spallanzanii and Styela plicata is interpreted to result from the preferential uptake of intermediate REE onto carboxylic sites. Moreover, the relationship observed between the Fe content and Zr/Hf ratio suggests that preferential Hf accumulation occurs via siderophore-like binding sites. Features of the REE bioaccumulation factors (BAF), in addition to the absolute La, Ce and Sm contents and Zr-Hf fractionation, allow definition of the different origins of studied elements in the investigated localities. Higher BAF values for La and Ce associated with larger REE contents and lower Zr/Hf values strongly suggest that the environmental REE distribution in the Termini Imerese harbour is influenced by the delivery of particles from industrial sources and power plants. On the contrary, the REE contents of biological tissues collected in the Cala tourist harbour are affected by the dust dissolution from automotive traffic. These results suggest that the geochemical behaviour of REE and Zr/Hf signature can be used in environmental studies of biological tissues for reconstructing the nature of anthropogenic contaminations.


Subject(s)
Environmental Monitoring/methods , Hafnium/analysis , Metals, Rare Earth/analysis , Polychaeta/chemistry , Zirconium/analysis , Animals , Dust , Sicily , Tissue Distribution , Vehicle Emissions
3.
Phys Chem Chem Phys ; 17(2): 1458-68, 2015 Jan 14.
Article in English | MEDLINE | ID: mdl-25429970

ABSTRACT

In this study, the interaction of cisplatin (1) and two potential antitumoral Pt(II) complexes (2 and 3) with a model DMPC bilayer was investigated by multinuclear NMR spectroscopy and MD simulations in order to understand its implication for the different antitumoral properties shown by the three complexes. In particular, (31)P, (13)C and (2)H solid state NMR experiments were performed to obtain information on the phase structure, phase transitions and structural and dynamic changes in the phospholipid bilayer upon interaction with the platinum complexes. On the other hand, MD calculations yielded free energy profiles for the different complexes across the bilayer; the results were analysed to obtain MD predictions on complex distribution with respect to the bilayer, as well as to establish their effects on the conformational equilibrium of the DMPC acyl chains. The combination of NMR and MD approaches highlighted that, whereas the more hydrophilic cisplatin tends to remain in the polar head group region causing a decrease in flexibility of the bilayer, the two new complexes enter into the bilayer. In particular, complex 2 is preferentially located relatively close to the surface, only slightly affecting the bilayer structure and mobility, while complex 3 penetrates more deeply, strongly perturbing the bilayer and giving rise to lateral phase separation.


Subject(s)
Antineoplastic Agents/metabolism , Cell Membrane/chemistry , Cisplatin/chemistry , Lipid Bilayers/chemistry , Molecular Dynamics Simulation , Organoplatinum Compounds/chemistry , Antineoplastic Agents/chemistry , Cell Membrane/metabolism , Cisplatin/metabolism , Dimyristoylphosphatidylcholine/chemistry , Lipid Bilayers/metabolism , Magnetic Resonance Spectroscopy , Molecular Conformation , Organoplatinum Compounds/metabolism
4.
Clin Ter ; 162(1): 11-8, 2011.
Article in Italian | MEDLINE | ID: mdl-21448540

ABSTRACT

AIMS: The aims of the study are to evaluate, in the Italian context, the presence and clinical features of early prodromal symptoms before the psychotic onset and, most of all, the duration of the period between the first onset of any psychiatric symptom and the psychotic onset (Duration of Untreated Illness). MATERIALS AND METHODS: The study was carried out on a sample of 296 inpatients with a diagnosis of "non-affective psychosis" enrolled in "Villa dei Fiori" inpatients Clinic in Rome. The retrospective analysis was developed using clinical records and clinical interview with patients and their parents. The evaluation of the psychotic onset and of DUI was assessed with the PANSS (Positive and Negative Symptoms Scale). RESULTS: The mean DUI is 4.7 ± 4.4 years. We found a connection between DUI and early symptoms of psycosis: depressive symptoms (4.9; DS=5.0) were most frequently observed, followed by anxiety symptoms (5.1; DS=4.8), eating disorders (5.7; DS=3.0); obsessive symptoms (4.5; DS=3.6); social withdrawal (5.9; DS=4.9); psychotic like symptoms (2.6; DS=1.3). DUI resulted lower in psychotic like symptoms than in the depressive ones. CONCLUSION: In Italy DUI turn out to be much longer than in other Country where do exists specialized services for early intervention. For this reason seem to be necessary to explore the opportunity to develop also in Italy specialized services for adolescents and young adults at risk and at their psychotic onset.


Subject(s)
Behavioral Symptoms/epidemiology , Inpatients/psychology , Psychotic Disorders/diagnosis , Adult , Age of Onset , Anxiety/epidemiology , Depression/epidemiology , Early Diagnosis , Feeding and Eating Disorders/epidemiology , Female , Hospitals, Psychiatric , Humans , Institutionalization/statistics & numerical data , Male , Middle Aged , Obsessive Behavior/epidemiology , Retrospective Studies , Rome/epidemiology , Social Isolation , Time Factors , Young Adult
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