Evidence of pyrite dissolution by Telephora terrestris Ehrh in the Libiola mine (Sestri Levante, Liguria, Italy)

Evidence of pyrite dissolution by Telephora terrestris Ehrh were observed for the first time in the abandoned sulphide Libiola mine in May 2017 (Sestri Levante, Liguria, Italy). This fungus is an ectomycorrhizal species able to colonize this extreme environment and bioaccumulate metals such as copper and silver in its fruiting bodies, and it is known to establish symbiosis with maritime pines present in the area, thus favouring their recolonization of the site. This paper presents evidence of T. terrestris promoted dissolution of sulphide minerals. This species can remove from soil not only metals possibly toxic to the pine trees, but it can also contribute to the ions bioaccumulation through the bioweathering of sulphide mineral grains (especially pyrite)

Sulfide weathering processes mediated by microfungi

This study aimed to experimentally investigate the interactions, the bioalteration, and the biocorrosion of sulfides mediated by three microfungi (Trichoderma harzianum group, Penicillium glandicola, P. brevicompactum) isolated within the open-air waste-rock dumps from Libiola mine (Liguria, Italy). Unaltered samples of pyrite-mineralizations from the same waste-rock dumps were ground and sieved into size fraction of 150-63 \u3bc m which resulted composed by single crystals of pyrite (>80 wt%), with minor quartz and trace amount of chalcopyrite. The mineral bioalteration tests were carried out for six weeks using Czapek-Dox agar medium (CZA). In each plate, four pyrite crystals or crystal fragments were set into the solid medium. After one week, pyrite grains were almost completely covered by mycelia of the three different fungi. The samples were examined, before and after the experimental procedure, using plane-polarized optical microscopy (transmitted- and reflected-light) and environmental scanning electron microscopy (ESEM-EDS). The ESEM analyses were performed in low-vacuum mode for the micromorphological analyses to characterize the evolution of the mineralfungi interactions during the different experimental steps. After six weeks covered by mycelia, the pyrite grains were collected and analyzed revealing that the surface of pyrite crystals was strongly corroded in all experimental tests. ESEM images underlined how pyrite alteration was strictlty associated with biological patterns (curves, rounded cracks, and sinuous traces). Corrosion patterns and etching pits were not related to specific crystallographic planes or weakness, but were randomly distributed on the crystal surfaces, in particular in correspondence of the fungal hyphae attachment. Moreover, in the same temporal interval, the control experiment performed in abiotic conditions did not show any dissolution evidences thus suggesting that in absence of fungal interactions the pyrite weathering did not occur or was much slower. The experimental results evidenced the active role of fungi in the pyrite crystal weathering and suggested that sulfide alteration was not only the consequence of the interactions between metabolites secreted by fungi and minerals, but there was also a possible bio-mechanical role of hyphae in corrosion through penetration, boring, and burrowing along weak crystal planes or microfractures. Finally, the evidences of biocorrosion led to evaluate the important role of fungi in the iron and sulfur cycles in sulfide-bearing materials, since fungal alteration systematically triggers sulfide to sulfate oxidation, causing local gypsum and Fe-oxyhydroxides precipitation within mycelium structure

Applied Tests to Select the Most Suitable Fungal Strain for the Recovery of Critical Raw Materials from Electronic Waste Powder

Electrical and electronic wastes (WEEEs) are a potential source of raw materials. The main challenge for scientists is to set up a reliable and eco-friendly process to recycle raw materials and precious elements from WEEEs. Today, we know that fungi could play an active role in green technologies aimed at recycling valuable elements. The bioaccumulation mechanism and bioleaching activity of filamentous fungal species have already been exploited fruitfully in extraction processes. However, not all fungal strains possess the same characteristics, and it is crucial to choose the right strains to use. In this work, we show a method to assess the precious elements’ recovery efficiency from WEEE using fungal strains. A CAS agar screening test for siderophore detection was carried out with three strains. The following plate accumulation test performed on a medium added with 120 ppm of electronic waste powder highlighted the differences in accumulation capability, growth rate, and biomass production. Among the elements in tested waste, yttrium, copper, and palladium show the highest bioconcentration factor. The results confirm the biotechnological potential of fungi to recover valuable elements at the bench scale, highlighting the importance of effective screening tests to assess the most efficient strain for each kind of waste

human induced alterations of the mycobiota in an alpine show cave italy sw alps

Anthropogenic alterations in show caves are well documented in scientific literature. One of the main sources of perturbation derives from visitors, acting as carriers of propagules and organic matter in the cave ecosystems. Such perturbation generally results in a significant alteration of the natural subterranean microbiota. In this study, we characterize the mycobiota of the superficial alluvial sediment (0–5 cm) of the Bossea show cave (NW-Italy) over two sampling seasons, aiming to investigate whether anthropogenic rather than natural factors contribute to the colonization and proliferation of alien mycobiota in the cave environment. We placed eighteen sampling plots at different distances from the touristic pathway that crosses the cave. The distance from the touristic pathway was used as proxy to sort the sampling plots in three groups according the degree of anthropogenic disturbance (high: 0–2 m; intermediate 2–40 m; low: >100 m). Moreover, in order to elucidate the potential effect of other factors, we introduced in our analysis the distance from the subterranean river and the distance from the cave entrance. In each plot, we collected two samples of alluvial sediment, in winter and summer. Fungi were isolated from each sample and identified by means of an integrated morphological approach. We observed a rich and diversified fungal community – 63 taxa of Zygomycota and Ascomycota plus several unidentified yeasts – consisting of both native and alien species. Regression analysis points out a decrease of the abundance and the diversity of viable propagules at increasing distances from the touristic pathway rather than the cave entrance or the subterranean river. Accordingly, the exogenous organic materials passively conveyed by tourists, possibly explains the higher proliferation of alien species in the proximity of the touristic pathway. There was also a seasonal variation in the diversity and abundance of propagules, which we interpreted in light of the peculiar microclimate of the cave. In a second step, we used Indicator Species Analysis to identify the most representative species of the different levels of anthropogenic disturbance. In particular, Aspergillus spelunceus was found to be indicator of low disturbance, whereas Mucor corticola and A. asperescens were found to be indicators of intermediate and high disturbance, respectively. Key words: anthropic disturbance, alluvial sediment, alien species, airborne fungi, environmental impact

Anti-SARS-CoV-2 Receptor-Binding Domain Total Antibodies Response in Seropositive and Seronegative Healthcare Workers Undergoing COVID-19 mRNA BNT162b2 Vaccination

Background: This study monitored total anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) RBD (receptor-binding domain) antibodies levels in a large population of healthcare workers undergoing mRNA COVID-19 vaccination. Methods. The study population consisted of employees of Pederzoli Hospital of Peschiera del Garda (Verona, Italy), who underwent voluntary vaccination with two doses of COVID-19 mRNA BNT162b2 (Comirnaty; Pfizer Inc). Venous blood was drawn immediately before the first vaccine dose, as well as 21 days (immediately before second vaccine dose) and 50 days afterwards. Humoral response was assessed with Roche Elecsys Anti-SARS-CoV-2 S total antibodies, on Roche Cobas 6000 (Roche Diagnostics). Results: The final study population consisted of 925 subjects (mean age, 44 \ub1 13 years; 457 women), 206 (22.3%) anti-SARS-CoV-2 baseline seropositive. The increase of total anti-SARS-CoV-2 RBD antibodies levels 21 days after the first vaccine dose was ~3 orders of magnitude higher in seropositive than in seronegative individuals (11782 vs. 42 U/mL; p < 0.001). Total anti-SARS-CoV-2 RBD antibodies levels further increased by over 30-fold after the second vaccine dose in baseline seronegative subjects, while such increase was only ~1.3-fold in baseline seropositive subjects. In multivariate analysis, total anti-SARS-CoV-2 RBD antibodies level was inversely associated with age after both vaccine doses and male sex after the second vaccine dose in baseline seronegative subjects, while baseline antibodies value significantly predicted immune response after both vaccine doses in baseline seropositive recipients. Conclusion: Significant difference exists in post-mRNA COVID-19 vaccine immune response in baseline seronegative and seropositive subjects, which seems dependent on age and sex in seronegative subjects, as well as on baseline anti-SARS-CoV-2 antibodies level in seropositive patients

An annotated checklist of macrofungi in broadleaf Mediterranean forests (NW Italy)

Three different broadleaf Mediterranean forests, each characterized by the dominance of Castanea sativa, Quercus cerris, and Fagus sylvatica, respectively, were intensively surveyed over 3 consecutive years to record a list of macrofungi. A total of 5,065 sporomata and 300 species (seven Ascomycota and 293 Basidiomycota) belonging to 18 orders, 59 families, and 117 genera were recorded. The ecology, community composition, and geographic distribution of the identified species are discussed and new records for Italy are also provided

MYC Rearranged Aggressive B-Cell Lymphomas: A Report on 100 Patients of the Fondazione Italiana Linfomi (FIL)

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