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23 result(s) for "Chiarantini, Laura"
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In vitro effects on calcium oxalate crystallization kinetics and crystal morphology of an aqueous extract from Ceterach officinarum: Analysis of a potential antilithiatic mechanism
Ceterach officinarum Willd is a plant widespread throughout Europe and used in southern Italy as a diuretic. Beliefs in the benefits of C. officinarum aqueous extract in the treatment of calcium oxalate kidney stones are widely held. Little is known, however, about the actual mechanism of its antilithiatic action. Our results in this in vitro study corroborate C. officinarum aqueous extract as a good source of antioxidants with a high antioxidant effects. Our results also demonstrate a major impact of C. officinarum aqueous extract on in vitro induced calcium oxalate crystallization kinetics and crystal morphology, showing its critical role in kidney stone formation and/or elimination. We show that progressively increasing doses of C. officinarum aqueous extract cause a sequence of effects. A powerful inhibitory action on calcium oxalate monohydrate (COM) growth and aggregation is first observed. C. officinarum aqueous extract also appears highly effective in stimulating nucleation increasing the number and reducing the size of COM crystals, which become progressively thinner, rounded and concave in a dose-dependent manner. These shape-modified COM crystals are known to be less adherent to renal tubular cells and more easily excreted through the urinary tract preventing kidney stone formation. Further, C. officinarum aqueous extract promotes the formation of calcium oxalate dihydrate (COD) rather than the monohydrate so that, at the highest concentrations used, only COD crystals are observed, in significant greater numbers with a clear reduction in their size, in a dose-dependent manner. Furthermore, AFM analyses allowed us to reveal the presence of C. officinarum component(s) on the surfaces of COD and modified COM crystals. The crystal surface adsorbed component(s) are shown to be similarly active as the total aqueous extract, suggesting a trigger factor which may direct crystal modification towards COD forms. In urolithiasis pathogenesis COD crystals are less dangerous than the COM forms due to their lower affinity for renal tubular cells. Our results are important in understanding the mechanisms which guide the modification induced by C. officinarum on the crystallization process. Based on these data, together with no adverse toxic effect being observed on the in vitro model of human intestinal enterocytes, C. officinarum aqueous extract could represent an attractive natural therapy for the treatment of urolithiasis.
Smoking habits, ETS exposure and knowledge of tobacco and e-cigarettes/HTPs among university students in Italy—a multicentre study
Background Tobacco smoking is a leading cause of morbidity and mortality worldwide, responsible for about 61,300 deaths annually in Italy. In addition to tobacco cigarettes, the use of electronic cigarettes (e-cigs) and heated tobacco products (HTPs) has increased among young people, raising public health concerns. This study aimed to investigate smoking habits, exposure to passive smoke, and awareness of health risks among Italian university students. Methods A multicentre observational survey was carried out by 8 Italian Universities to promote smoke-free lifestyles among students. All students were sent an anonymous online questionnaire via email regarding their smoking habits, their exposure to second-hand smoke, and their knowledge of, and opinions on, smoking. Descriptive statistics and multinomial logistic regression models were applied to assess associations between tobacco and nicotine use with sex and areas of study. Results A total of 20,644 students from different study areas were included in the study: 62.3% did not smoke, 9.9% were former smokers, 14.4% were smokers of tobacco cigarettes exclusively, 6.5% of e-cigs or HTPs, and 6.9% were dual smokers (total smokers 27.8%). Smoking prevalence was highest among Law (35.9%) and Economics (33.7%) students, and lowest among Medicine and Sciences and Technology students (22%). Males were more likely to smoke tobacco or to be dual users, while females reported higher e-cig use; most smokers consumed fewer than 10 cigarettes/day with mild nicotine dependence. Among e-cig/HTP users, over 60% started as an alternative to cigarettes, but 22% started or resumed tobacco smoking after using them and 22% had never smoked tobacco cigarettes before. Passive smoke exposure was common: 26.5% lived with smokers and 58.9% reported peer exposure. While nearly all students recognized the harms of both active and passive tobacco smoking, only 60% considered passive exposure to e-cigs/HTPs as dangerous. About 70% were favourable to stricter enforcement of university smoking bans. Conclusions: Traditional cigarettes remain the most used product among Italian university students, but e-cigs and HTPs are increasingly widespread and socially accepted, even among never smokers. Awareness of the risks of alternative products is limited, and passive exposure remains underestimated. These findings underline the importance of targeted educational campaigns and stronger enforcement of smoke-free policies in academic settings.
Particle-Bound Mercury Characterization in the Central Italian Herbarium of the Natural History Museum of the University of Florence (Italy)
Museums air quality can be negatively affected by treatments with heavy metals compounds employed to prevent pest infestations. Among these, the past use of mercury dichloride (HgCl2) on herbaria artifacts currently produces high levels of indoor atmospheric gaseous mercury (Hg0) and possibly of particulate bound Hg (PBM), i.e., the particulate matter containing Hg. This study evaluates the PBM pollution in the Central Italian Herbarium (Natural History Museum of the University of Florence, Italy), characterizing the size range and chemical speciation with SEM-EDS microanalysis. The analysis of the total Hg concentration in the samples allowed to calculate the workers exposure risk to this pollutant. PBM is almost totally classifiable as fine particulate with a significant dimensional increase in a period of scarce attendance of the Herbarium rooms. The microanalysis indicates that Hg is essentially bound to S, highlighting the change of Hg speciation from the original association with Cl. The average Hg concentration reveals a potential health risk for workers as result of multiple Hg exposure pathways, mainly by ingestion. The study provides information for characterizing PBM pollution that could affect a workplace atmosphere and a useful basis to evaluate and correctly design solution strategies to reduce the contamination levels and protect workers’ health.
Cydonia oblonga Mill. Pulp Callus Inhibits Oxidative Stress and Inflammation in Injured Cells
The pharmacological activity of a callus extract from the pulp of Cydonia oblonga Mill., also known as quince, was investigated in murine macrophage (RAW 264.7) and human keratinocyte (HaCaT) cell lines. In particular, the anti-inflammatory activity of C. oblonga Mill. pulp callus extract was assessed in lipopolysaccharides (LPS)-treated RAW 264.7 by the Griess test and in LPS-treated HaCaT human keratinocytes by examining the expression of genes involved in the inflammatory process, including nitric oxide synthase (iNOS), interleukin-6 (IL-6), interleukin-1β (IL-1β), nuclear factor-kappa-B inhibitor alfa (ikBα), and intercellular adhesion molecule (ICAM). The antioxidant activity was evaluated by quantizing the reactive oxygen species (ROS) production in the hydrogen peroxide and tert-butyl hydroperoxide-injured HaCaT cell line. The obtained results indicate that C. oblonga callus from fruit pulp extract has anti-inflammatory and antioxidant activities, suggesting its possible application in delaying and preventing acute or chronic diseases associated with aging or in the treatment of wound dressing.
Effects of biogenerated ferric hydroxides nanoparticles on truffle mycorrhized plants
Truffles are highly valuable ectomycorrhizal fungi that grow naturally in alkaline, calcareous soils. Iron deficiency chlorosis is a common problem in truffle (Tuber spp.) cultivation due to the high quantity of lime added to increase the pH of acidic soils. In this work, the effects of ferric hydroxide nanoparticles embedded in an exopolysaccharide (Fe-EPS NPs), extracted from cultures of Klebsiella oxytoca DSM 29614, were investigated on Quercus robur seedlings under greenhouse conditions. The plants were inoculated with Tuber borchii (the bianchetto truffle) and were cultivated with and without iron nanoparticle additions and compared with non-inoculated control plants. The seedlings were grown in limed soil in order to induce iron deficiency. Low doses of Fe-EPS NPs had a beneficial effect on the growth of the plants inoculated with T. borchii, increasing their height and reducing their leaf chlorosis 5 months after the first Fe-EPS NP treatment. Moreover, Fe-EPS NP treatments significantly increased the level of T. borchii mycorrhizal colonization and the ectomycorrhizal mantle thickness. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) applied to cross sections of mycorrhizas showed that Fe accumulated in the fungal mantle and apparently was slowly released serving as a resilient reservoir of iron for the plant. The results suggest that the application of Fe-EPS NPs is a promising technique in the production of Tuber mycorrhized plants in the nursery and could have future applications in the field.
Shedding light on the microstructure and chemical composition of rare early medieval coins from Italy (Berengario I) by combining pXRF and SEM–EDX analysis
The application of analytical techniques for archaeometric investigation poses a major problem when dealing with objects of high values such as coins. Due to the unique character and rarity of some coins, any kind of analysis should be better non-destructive, which means that neither original sample material can be taken nor any kind of modification is allowed. Moreover, ancient Ag–Cu coins are usually affected by silver surface enrichment which extension in depth can reach several hundreds of microns, far beyond the penetration depth of surface techniques such as pXRF. In order to gain insight into the composition and microstructure of ancient coins, to establish their “real fineness” and to determine the reliability of data obtained with pXRF, the present paper presents, for the first time in literature, the results of the compositional and microstructural features of four medieval denari made of silver–copper alloy obtained by pXRF, SEM–EDX, and FTIR analyses. Three of them are some rare denari in the name of Berengario I minted in Pavia (898–900/902–915? AD) while the fourth coin is one denarius in the name of Henry IV-V minted in Lucca (1100–1130 AD). Results provided by SEM–EDX and FTIR analyses clearly demonstrate that archeological samples could be deeply heterogeneous due to both production techniques and corrosion phenomena. This poses a big question on the representativity of analytical data obtained only with non-destructive superficial methods or with those methods where only a few spot analyses were performed. However, the pXRF results provided a data set that, even if not particularly accurate, can clearly evidence, like for Berengario I coins, some completely unexpected heterogeneities, that represent without a doubt, a big interesting archaeometric anomaly. Despite the limited number of examples, it was possible to provide important data on two monetary types of difficult chronological collocation and attribution.
Tracing the lead source of maiolica: a pilot isotopic study on artefacts from the area of Florence, Italy  (fifteenth–nineteenth century)
The manufacturing of Italian maiolica (tin-glazed pottery) was extremely appreciated during the Middle Ages and Renaissance, leading to the production and collection of a rich cultural heritage. This pilot study aims to characterize the production technique and the origin of the lead used as a flux in a set of samples of maiolica glazes made in the area of Florence over a wide time span, ranging from the fifteenth to the nineteenth century. In particular, this is the first study that applies provenance analysis, using lead isotopes, to tin-glazed artefacts made in the site of Montelupo Fiorentino and by the Ginori manufactory in Doccia (Florence, Italy), both important production centres of ceramics in Italy. The samples were first analysed by scanning electron microscopy to characterize their layer structure and chemical composition. Lead isotope analysis was then performed by thermal ionization mass spectrometry and showed that the samples tend to be distributed into distinct groups according to their period of production. Moreover, the comparison with the lead isotope composition of the deposits of the European and circum-Mediterranean area from which lead was historically extracted showed that the isotopic composition of the samples differs from that of the Italian deposits, suggesting that lead was imported from abroad. The isotopic composition of all the investigated maiolica glazes is compatible with German ore deposits, in agreement with what is reported by the historical sources relating to the lead supply areas.
Monitoring of Airborne Mercury: Comparison of Different Techniques in the Monte Amiata District, Southern Tuscany, Italy
In the present study, mercury (Hg) concentrations were investigated in lichens (Flavoparmelia caperata (L.) Hale, Parmelia saxatilis (L.) Ach., and Xanthoria parietina (L.) Th.Fr.) collected in the surrounding of the dismissed Abbadia San Salvatore Hg mine (Monte Amiata district, Italy). Results were integrated with Hg concentrations in tree barks and literature data of gaseous Hg levels determined by passive air samplers (PASs) in the same area. The ultimate goal was to compare results obtained by the three monitoring techniques to evaluate potential mismatches. Lichens displayed 180–3600 ng/g Hg, and Hg concentrations decreased exponentially with distance from the mine. Mercury concentration was lower than in Pinus nigra barks at the same site. There was a moderate correlation between Hg in lichen and Hg in bark, suggesting similar mechanisms of Hg uptake and residence times. However, correlation with published gaseous Hg concentrations (PASs) was moderate at best (Kendall Tau = 0.4–0.5, p > 0.05). The differences occurred because a) PASs collected gaseous Hg, whereas lichens and barks also picked up particulate Hg, and b) lichens and bark had a dynamic exchange with the atmosphere. Lichen, bark, and PAS outline different and complementary aspects of airborne Hg content and efficient monitoring programs in contaminated areas would benefit from the integration of data from different techniques.
Non-Invasive Characterization of Maiolica Layer Structure by Terahertz Time-Domain Imaging
The characterization of the layered structure is of paramount importance for the study of maiolica wares (tin-glazed pottery). This paper presents the potentialities of Terahertz Time-Domain Imaging (THz-TDI) as a tool to perform non-invasive stratigraphic analysis of the maiolica objects under test. Samples with different types of stratigraphy, as testified by preliminary SEM-EDS analysis, were investigated by THz-TDI in laboratory conditions. The collected THz data were processed by means of noise filtering procedures and a time-of-flight-based imaging approach and the achieved results corroborate the ability to identify glaze layers, whose electromagnetic properties, i.e., the refraction index and the dielectric permittivity value, were estimated by taking into account both THz-TDI and SEM-EDS data. However, layers applied over the white glaze (namely, a transparent overglaze and a luster decoration) were not detected, probably since their thickness is below the range resolution of the adopted THz-TDI system. Morphological features hidden under the surface were also identified and they provided information about the manufacturing technique.
Medieval Pb (Cu-Ag) Smelting in the Colline Metallifere District (Tuscany, Italy): Slag Heterogeneity as a Tracer of Ore Provenance and Technological Process
Archaeological investigations of the Colline Metallifere district (Southern Tuscany, Italy) have highlighted several Medieval sites located close to the main Cu-Pb-Fe (Ag) ore occurrences. This study is focused on the investigation of late-medieval slags from Cugnano and Montieri sites using both geochemical and mineralogical methods to understand slag heterogeneities as result of ore differences and technological processes. Matte-rich slags present in both sites (with abundant matte ± speiss and frequent relict phases) represent waste products related to primary sulphide ore smelting to obtain a raw lead bullion. The distribution of slags between the Ca-rich or Fe-rich dominant composition, and the consequent mineralogy, are tracers of the different ore–gangue association that occurred in the two sites. Silver is present only in very small matte-rich slags and ores enclosed within the mortar of the Montieri site; wastes derived from silver-rich mineral charges were probably crushed for the recovery of silver. Matte-poor slags found at Montieri represent a second smelting; raw lead bullion obtained from matte slags (both Fe- and Ca-rich) was probably re-smelted, adding silica and Al2O3-phase-rich fluxes, under more oxidizing conditions to reduce metal impurities. This second step was probably employed for Zn-rich lead ores; this process helped to segregate zinc within slags and improve the quality of the metal.