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151.
Jacopo Burrello Sara Bolis Carolina Balbi Alessio Burrello Elena Provasi Elena Caporali Lorenzo Grazioli Gauthier Andrea Peirone Fabrizio D'Ascenzo Silvia Monticone Lucio Barile Giuseppe Vassalli 《Journal of cellular and molecular medicine》2020,24(17):9945-9957
The current standard biomarker for myocardial infarction (MI) is high‐sensitive troponin. Although powerful in clinical setting, search for new markers is warranted as early diagnosis of MI is associated with improved outcomes. Extracellular vesicles (EVs) attracted considerable interest as new blood biomarkers. A training cohort used for diagnostic modelling included 30 patients with STEMI, 38 with stable angina (SA) and 30 matched‐controls. Extracellular vesicle concentration was assessed by nanoparticle tracking analysis. Extracellular vesicle surface‐epitopes were measured by flow cytometry. Diagnostic models were developed using machine learning algorithms and validated on an independent cohort of 80 patients. Serum EV concentration from STEMI patients was increased as compared to controls and SA. EV levels of CD62P, CD42a, CD41b, CD31 and CD40 increased in STEMI, and to a lesser extent in SA patients. An aggregate marker including EV concentration and CD62P/CD42a levels achieved non‐inferiority to troponin, discriminating STEMI from controls (AUC = 0.969). A random forest model based on EV biomarkers discriminated the two groups with 100% accuracy. EV markers and RF model confirmed high diagnostic performance at validation. In conclusion, patients with acute MI or SA exhibit characteristic EV biomarker profiles. EV biomarkers hold great potential as early markers for the management of patients with MI. 相似文献
152.
Arun K. Bose Arthur Gessler Andreas Bolte Alessandra Bottero Allan Buras Maxime Cailleret J. Julio Camarero Matthias Haeni Ana‐Maria Here Andrea Hevia Mathieu Lvesque Juan C. Linares Jordi Martinez‐Vilalta Luis Matías Annette Menzel Raúl Snchez‐Salguero Matthias Saurer Michel Vennetier Daniel Ziche Andreas Rigling 《Global Change Biology》2020,26(8):4521-4537
Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees’ phenotypic variability, which is, in turn, affected by long‐term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree‐level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree‐, site‐, and drought‐related factors and their interactions driving the tree‐level resilience to extreme droughts. We used a tree‐ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid‐elevation and low productivity sites from 1980–1999 to 2000–2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree‐level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long‐term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation. 相似文献
153.
154.
Dung Quang Nguyen Dominik Schneider Nicole Brinkmann Bin Song Dennis Janz Ingo Schöning Rolf Daniel Rodica Pena Andrea Polle 《Environmental microbiology》2020,22(8):3081-3095
Root-associated fungi (RAF) link nutrient fluxes between soil and roots and thus play important roles in ecosystem functioning. To enhance our understanding of the factors that control RAF, we fitted statistical models to explain variation in RAF community structure using data from 150 temperate forest sites covering a broad range of environmental conditions and chemical root traits. We found that variation in RAF communities was related to both root traits (e.g., cations, carbohydrates, NO3−) and soil properties (pH, cations, moisture, C/N). The identified drivers were the combined result of distinct response patterns of fungal taxa (determined at the rank of orders) to biotic and abiotic factors. Our results support that RAF community variation is related to evolutionary adaptedness of fungal lineages and consequently, drivers of RAF communities are context-dependent. 相似文献
155.
Susanna Gorrasi Marcella Pasqualetti Andrea Franzetti Francesca Pittino Massimiliano Fenice 《Environmental microbiology》2020,22(10):4356-4366
Vibrio species are ubiquitous in a number of different aquatic environments and promptly adapting to environmental changes due to high genome plasticity. The presence of these bacteria in marine salterns, in relation to a salinity gradient has been not investigated yet. Moreover, it is not clear if these hypersaline environments could represent a reservoir for Vibrio spp. This work investigated, through a metagenetic approach, the distribution of Vibrio (over 2 years) in different ponds along the salinity gradient within the ‘Saline di Tarquinia’ salterns, considering also the adjacent coastal waters and an isolated brine storage basin (BSB). Vibrio occurrence was higher in the sea than in the ponds and BSB, where it usually represented a rare taxon (abundance <1%). In the sea, it showed abundances in-between 1%–2.6% in 8 months out of 24. Four OTUs were assigned to the Vibrio genus; except for one that was more abundant in BSB, the others were much higher in the sea. Redundancy analysis (RDA) suggested a different distribution of the OTUs in relation to water temperature and salinity. Vibrio was found, even with low abundances, at the highest salinities also, suggesting the salterns as a possible reservoir for the bacterium. 相似文献
156.
Katarína Šoltys Matej Planý Paola Biocca Valentina Vianello Mária Bučková Andrea Puškárová Maria Carla Sclocchi Piero Colaizzi Marina Bicchieri Domenico Pangallo Flavia Pinzari 《Environmental microbiology》2020,22(4):1517-1534
A multidisciplinary approach was carried out in order to study the biodeterioration and the associated microbiome of a XVIII Century wax seal coloured with minium. A small wax seal fragment was observed by scanning electron microscopy combined with energy dispersive spectroscopy in non-destructive mode. The same object was analysed by Raman and Fourier-transform infrared spectroscopy. The identification of the microbiota growing on the seal was performed with both a culture-dependent strategy, combined with hydrolytic assays, and high-throughput sequencing using the MinION platform. The whole bacterial 16S rRNA gene and the fungal markers ITS and 28S rRNA were targeted. It was observed that the carnauba wax coloured with lead tetroxide (minium) was covered by a biofilm consisting of a network of filaments and other structures of microbial origin. The culture-dependent and culture-independent investigations showed the presence of a complex microbiota composed mainly by fungal members, which demonstrated interesting properties related to lipids and lead processing. The formation of lead soaps and secondary biogenic minerals was also described. 相似文献
157.
158.
159.
Olga A. Kildisheva Kingsley W. Dixon Fernando A. O. Silveira Ted Chapman Alice Di Sacco Andrea Mondoni Shane R. Turner Adam T. Cross 《Restoration Ecology》2020,28(Z3):S256-S265
From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re‐establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record‐keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning. 相似文献
160.
Andrea Ghirardo Frida Lindstein Kerstin Koch Franz Buegger Michael Schloter Andreas Albert Anders Michelsen J. Barbro Winkler Jrg‐Peter Schnitzler Riikka Rinnan 《Global Change Biology》2020,26(3):1908-1925
Warming occurs in the Arctic twice as fast as the global average, which in turn leads to a large enhancement in terpenoid emissions from vegetation. Volatile terpenoids are the main class of biogenic volatile organic compounds (VOCs) that play crucial roles in atmospheric chemistry and climate. However, the biochemical mechanisms behind the temperature‐dependent increase in VOC emissions from subarctic ecosystems are largely unexplored. Using 13CO2‐labeling, we studied the origin of VOCs and the carbon (C) allocation under global warming in the soil–plant–atmosphere system of contrasting subarctic heath tundra vegetation communities characterized by dwarf shrubs of the genera Salix or Betula. The projected temperature rise of the subarctic summer by 5°C was realistically simulated in sophisticated climate chambers. VOC emissions strongly depended on the plant species composition of the heath tundra. Warming caused increased VOC emissions and significant changes in the pattern of volatiles toward more reactive hydrocarbons. The 13C was incorporated to varying degrees in different monoterpene and sesquiterpene isomers. We found that de novo monoterpene biosynthesis contributed to 40%–44% (Salix) and 60%–68% (Betula) of total monoterpene emissions under the current climate, and that warming increased the contribution to 50%–58% (Salix) and 87%–95% (Betula). Analyses of above‐ and belowground 12/13C showed shifts of C allocation in the plant–soil systems and negative effects of warming on C sequestration by lowering net ecosystem exchange of CO2 and increasing C loss as VOCs. This comprehensive analysis provides the scientific basis for mechanistically understanding the processes controlling terpenoid emissions, required for modeling VOC emissions from terrestrial ecosystems and predicting the future chemistry of the arctic atmosphere. By changing the chemical composition and loads of VOCs into the atmosphere, the current data indicate that global warming in the Arctic may have implications for regional and global climate and for the delicate tundra ecosystems. 相似文献