Seasonal flight activity and genetic relatedness of Torymus species in Italy

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Emerging from the ice-fungal communities are diverse and dynamic in earliest soil developmental stages of a receding glacier

We used amplicon sequencing and isolation of fungi from in-growth mesh bags to identify active fungi in three earliest stages of soil development (SSD) at a glacier forefield (0–3, 9–14, 18–25 years after retreat of glacial ice). Soil organic matter and nutrient concentrations were extremely low, but the fungal diversity was high [220 operational taxonomic units (OTUs)/138 cultivated OTUs]. A clear successional trend was observed along SSDs, and species richness increased with time. Distinct changes in fungal community composition occurred with the advent of vascular plants. Fungal communities of recently deglaciated soil are most distinctive and rather similar to communities typical for cryoconite or ice. This indicates melting water as an important inoculum for native soil. Moreover, distinct seasonal differences were detected in fungal communities. Some fungal taxa, especially of the class Microbotryomycetes, showed a clear preference for winter and early SSD. Our results provide insight into new facets regarding the ecology of fungal taxa, for example, by showing that many fungal taxa might have an alternative, saprobial lifestyle in snow-covered, as supposed for a few biotrophic plant pathogens of class Pucciniomycetes. The isolated fungi include a high proportion of unknown species, which can be formally described and used for experimental approaches.     

Parasitism and alternative reproductive tactics in Northern chamois

Alternative reproductive tactics (ARTs), discrete phenotypic variations evolved to maximize fitness, may entail different cost‐benefit trade‐offs. In large mammals, differences in costs associated with ARTs—including energy expenditure and parasite infection—are typically greatest during the breeding season. Nonetheless, physiological and behavioral differences between ARTs can manifest throughout the year, possibly involving costs that may contribute to maintain ARTs within populations. Using the number of nematode larvae per gram of feces (LPG) as a proxy, we explored the temporal changes in lung parasite infection in territorial and nonterritorial male chamois Rupicapra in the Gran Paradiso National Park (Italy), between 2011 and 2012. We aimed to identify which tactic‐specific physiological and behavioral features (including age, hormonal levels, inter‐ and intrasexual interactions, and space use) or climatic factors (temperature and precipitation) best explained yearly variation in parasite infection within and between ARTs. Generalized additive mixed models showed that the fecal larval counts of lung nematodes underwent strong temporal changes in both male types. Differences between ARTs (with higher LPG values in territorial than nonterritorial males) were greatest during the rut and—to a lesser extent—in spring, respectively, at the peak and at the onset of territoriality. The difference in LPG between tactics was largely explained by the greater levels of hormone metabolites in territorial males during the rut. The other variables did not contribute significantly to explain the different shedding of larvae within and between ARTs. Our analysis suggests that different values of LPG between territorial and nonterritorial males are largely a result of tactic‐specific differences in the secretion of hormone metabolites, but only during the rut. To clarify whether rut‐related parasitism contributes to the maintenance of ARTs, tactic‐specific life history trade‐offs, for example, between reproduction and parasite‐related mortality, must be investigated.     

Precise Gene Editing Preserves Hematopoietic Stem Cell Function following Transient p53-Mediated DNA Damage Response

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Structural and functional fingerprint of the mitochondrial ATP-binding cassette transporter Mdl1 from Saccharomyces cerevisiae

The ATP-binding cassette half-transporter Mdl1 from Saccharomyces cerevisiae has been proposed to be involved in the quality control of misassembled respiratory chain complexes by exporting degradation products generated by the m-AAA proteases from the matrix. Direct functional or structural data of the transport complex are, however, not known so far. After screening expression in various hosts, Mdl1 was overexpressed 100-fold to 1% of total mitochondrial membrane protein in S. cerevisiae. Based on detergent screens, Mdl1 was solubilized and purified to homogeneity. Mdl1 showed a high binding affinity for MgATP (Kd = 0.26 microm) and an ATPase activity with a Km of 0.86 mm (Hill coefficient of 0.98) and a turnover rate of 2.6 ATP/s. Mutagenesis of the conserved glutamate downstream of the Walker B motif (E599Q) or the conserved histidine of the H-loop (H631A) abolished ATP hydrolysis, whereas ATP binding was not affected. Mdl1 reconstituted into liposomes showed an ATPase activity similar to the solubilized complex. By single particle electron microscopy, a first three-dimensional structure of the mitochondrial ATP-binding cassette transporter was derived at 2.3-nm resolution, revealing a homodimeric complex in an open conformation.     

Determination of ochratoxin A in dry-cured meat products by a HPLC-FLD quantitative method

A fast and sensitive method for the quantification of the mycotoxin ochratoxin A (OTA) in dry-cured meat products has been developed, which does not require a clean-up step, by HPLC with an alkaline mobile phase (pH 9.8). Validation procedures for specificity, trueness, ruggedness, stability, recovery and repeatability were performed. The decision limit (CC alpha) and the decision capability (CC beta) were calculated at 1.10 and 1.23 microg/kg, respectively. The procedure was applied to representative dehydration levels of dry-cured meat samples.     

New 2,6,9-trisubstituted adenines as adenosine receptor antagonists: a preliminary SAR profile

A new series of 2,6,9-trisubstituted adenines (5–14) have been prepared and evaluated in radioligand binding studies for their affinity at the human A₁, A_2A and A₃ adenosine receptors and in adenylyl cyclase experiments for their potency at the human A_2B subtype. From this preliminary study the conclusion can be drawn that introduction of bulky chains at the N ⁶ position of 9-propyladenine significantly increased binding affinity at the human A₁ and A₃ adenosine receptors, while the presence of a chlorine atom at the 2 position resulted in a not univocal effect, depending on the receptor subtype and/or on the substituent present in the N ⁶ position. However, in all cases, the presence in the 2 position of a chlorine atom favoured the interaction with the A_2A subtype. These results demonstrated that, although the synthesized compounds were found to be quite inactive at the human A_2B subtype, adenine is a useful template for further development of simplified adenosine receptor antagonists with distinct receptor selectivity profiles.     

Proteome analysis of whole saliva: a new tool for rheumatic diseases--the example of Sjögren's syndrome

Sj?gren's syndrome (pSS) is a systemic disease that affects salivary glands directly, and is therefore expected to influence the composition of human whole saliva (WS) fluid. The aim of this study was to characterize the WS proteins of pSS patients using a proteomic approach to assess a valid procedure to examine the global changes of the salivary protein profiles in connective tissue disorders. The WS proteins expressed in patients affected by pSS and healthy volunteers were analyzed using the 2-DE technique. The WS protein pattern was altered in pSS patients compared to controls, with a decrease in some of the typical salivary proteins. Particularly, a remarkable alteration of carbonic anhydrase VI was observed. Moreover, a comparison of WS protein profile of pSS patients with the one obtained from controls revealed a set of differentially expressed proteins. These proteins were related to acute and chronic inflammation while some others were involved in oxidative stress injury. These findings are in line with the systemic immuno-inflammatory aspects of pSS and open the possibility for a systematic search of diagnostic biomarkers and targets for therapeutic intervention in pSS.     

Integrated analytical approach in veal calves administered the anabolic androgenic steroids boldenone and boldione: urine and plasma kinetic profile and changes in plasma protein expression

Surveillance of illegal use of steroids hormones in cattle breeding is a key issue to preserve human health. To this purpose, an integrated approach has been developed for the analysis of plasma and urine from calves treated orally with a single dose of a combination of the androgenic steroids boldenone and boldione. A quantitative estimation of steroid hormones was obtained by LC-APCI-Q-MS/MS analysis of plasma and urine samples obtained at various times up to 36 and 24 h after treatment, respectively. These experiments demonstrated that boldione was never found, while boldenone alpha- and beta-epimers were detected in plasma and urine only within 2 and 24 h after drug administration, respectively. Parallel proteomic analysis of plasma samples was obtained by combined 2-DE, MALDI-TOF-MS and muLC-ESI-IT-MS/MS procedures. A specific protein, poorly represented in normal plasma samples collected before treatment, was found upregulated even 36 h after hormone treatment. Extensive mass mapping experiments proved this component as an N-terminal truncated form of apolipoprotein A1 (ApoA1), a protein involved in cholesterol transport. The expression profile of ApoA1 analysed by Western blot analysis confirmed a significant and time dependent increase of this ApoA1 fragment. Then, provided that further experiments performed with a growth-promoting schedule will confirm these preliminary findings, truncated ApoA1 may be proposed as a candidate biomarker for steroid boldenone and possibly other anabolic androgens misuse in cattle veal calves, when no traces of hormones are detectable in plasma or urine.