Utilizzo di tecniche di prospezione geoelettrica per lo studio dell'interazione suolo-radici

In this study we aimed to use the technique of geoeletrical prospection ERT, to investigate the interaction between the soil and the root system of an Olive tree sited in Tuscany. The data have been elaborated through various softwares like Prosys II, Paraview and MatLab. The results obtained show how this approach can give us information related to the location of the roots in the soil, and trace the diffusion of the wet volume in a time-lapse sequenceope

Attenuation of Helicobacter pylori-induced gastric inflammation by prior cag− strain (AM1) infection in C57BL/6 mice

Helicobacter pylori, colonize in stomach of ~50% of the world population. cag pathogenicity Island of H. pylori is one of the important virulent factors that attributed to gastric inflammation. Coinfection with H. pylori strain with different genetic makeup alters the degree of pathogenicity and susceptibility towards antibiotics. The present study investigates host immunomodulatory effects of H. pylori infection by both cag+ strain (SS1) and cag− strain (AM1). C57BL/6 mice were infected with AM1 or SS1 strain as well as AM1 followed by SS1 (AM1/SS1) and vice versa. Results: Mice infected with AM1/SS1 strain exhibited less gastric inflammation and reduced proMMP9 and proMMP3 activities in gastric tissues as compared to SS1/SS1 and SS1/AM1 infected groups. The expression of both MMP9 and MMP3 followed similar trend like activity in infected tissues. Both Th1 and Th17 responses were induced by SS1 strain more profoundly than AM1 strain infection which induced solely Th1 response in spleen and gastric tissues. Moreover, IFN-γ, TNF-α, IL-1β and IL-12 were significantly downregulated in mice spleen and gastric tissues infected by AM1/SS1 compared to SS1/SS1 but not with SS1/AM1 coinfection. Surprisingly, IL-17 level was dampened significantly in AM1/ SS1 compared to SS1/AM1 coinfected groups. Furthermore, number of Foxp3+ T-regulatory (Treg) cells and immunosuppressive cytokines like IL-10 and TGF-β were reduced in AM1/SS1 compared to SS1/SS1 and SS1/AM1 coinfected mice gastric tissues. Conclusions: These data suggested that prior H. pylori cag− strain infection attenuated the severity of gastric pathology induced by subsequent cag+ strain in C57BL/6 mice. Prior AM1 infection induced Th1 cytokine IFN-γ, which reduced the Th17 response induced by subsequent SS1 infection. The reduced gastritis in AM1/SS1-infected mice might also be due to enrichment of AM1- primed Treg cells in the gastric compartment which inhibit Th1 and Th17 responses to subsequent SS1 infection. In summary, prior infection by non-virulent H. pylori strain (AM1) causes reduction of subsequent virulent strain (SS1) infection by regulation of inflammatory cytokines and MMPs expressio

Genomic structure and insertion sites of Helicobacter pylori prophages from various geographical origins

We present the full genomic sequences, insertion sites and phylogenetic analysis of 28 prophages found in H. pylori isolates from patients of distinct disease types, ranging from gastritis to gastric cancer, and geographic origins, covering most continents. The gentic diversity of H pylori is known to be influenced by these genomic elements including prophages who’s geneomes range from 22.6 to 33.0 Kbp. There was a high conservation of integration site shared in over 50% of cases with greater than 40% or prophage genomes harbouring insertion sequences (IS). Furthermore prophage genomes present a robust phylogeographic pattern, revealing four distinct clusters: one African, one Asian and two European prophage populations. There was evidence of recombination within the genome of some prophages, which resulted in genome mosaics composed by different populations, which may yield additional H. pylori phenotypes

Delineation of hydrocarbon contaminants with multi-frequency complex conductivity imaging

The characterization of contaminated sites is a serious issue that requires a number of techniques to be deployed in the field to reconstruct the geometry, hydraulic properties and state of contamination of the shallow subsurface, often at the hundreds of meter scale with metric resolution. Among the techniques that have been proposed to complement direct investigations (composed of drilling, sampling, and laboratory characterization) are geophysical methods, which can provide extensive spatial coverage both laterally and at depth with the required resolution. However, geophysical methods only measure physical properties that are indirectly related to contamination, and their correlation may be difficult to ascertain without direct ground truth. In this study, we present a successful example where the results of complex conductivity measurements conducted in an imaging framework are compared with direct evidence of subsoil contamination at a jet fuel impacted site. Thus, proving that a combination of direct and indirect investigations can be successfully used to image a site in its complex (potentially 3D) structure in order to build a reliable conceptual model of the site

Dual RNA-seq of Nontypeable Haemophilus influenzae and Host Cell Transcriptomes Reveals Novel Insights into Host-Pathogen Cross Talk

ABSTRACT The ability to adhere and adapt to the human respiratory tract mucosa plays a pivotal role in the pathogenic lifestyle of nontypeable Haemophilus influenzae (NTHi). However, the temporal events associated with a successful colonization have not been fully characterized. In this study, by reconstituting the ciliated human bronchial epithelium in vitro, we monitored the global transcriptional changes in NTHi and infected mucosal epithelium simultaneously for up to 72 h by dual RNA sequencing. The initial stage of colonization was characterized by the binding of NTHi to ciliated cells. Temporal profiling of host mRNA signatures revealed significant dysregulation of the target cell cytoskeleton elicited by bacterial infection, with a profound effect on the intermediate filament network and junctional complexes. In response to environmental stimuli of the host epithelium, NTHi downregulated its central metabolism and increased the expression of transporters, indicating a change in the metabolic regime due to the availability of host substrates. Concurrently, the oxidative environment generated by infected cells instigated bacterial expression of stress-induced defense mechanisms, including the transport of exogenous glutathione and activation of the toxin-antitoxin system. The results of this analysis were validated by those of confocal microscopy, Western blotting, Bio-plex, and real-time quantitative reverse transcription-PCR (qRT-PCR). Notably, as part of our screening for novel signatures of infection, we identified a global profile of noncoding transcripts that are candidate small RNAs (sRNAs) regulated during human host infection in Haemophilus species. Our data, by providing a robust and comprehensive representation of the cross talk between the host and invading pathogen, provides important insights into NTHi pathogenesis and the development of efficacious preventive strategies. IMPORTANCE Simultaneous monitoring of infection-linked transcriptome alterations in an invading pathogen and its target host cells represents a key strategy for identifying regulatory responses that drive pathogenesis. In this study, we report the progressive events of NTHi colonization in a highly differentiated model of ciliated bronchial epithelium. Genome-wide transcriptome maps of NTHi during infection provided mechanistic insights into bacterial adaptive responses to the host niche, with modulation of the central metabolism as an important signature of the evolving milieu. Our data indicate that infected epithelia respond by substantial alteration of the cytoskeletal network and cytokine repertoire, revealing a dynamic cross talk that is responsible for the onset of inflammation. This work significantly enhances our understanding of the means by which NTHi promotes infection on human mucosae and reveals novel strategies exploited by this important pathogen to cause invasive disease

WATZON: the Italian network of ecohydrology and critical zone observatories

The Italian initiative WATZON (WATer mixing in the critical ZONe) is a network of instrumented sites, bringing together six pre-existing long-term research observatories monitoring different compartments of the Critical Zone - the Earth's permeable near-surface layer from the tops of the trees to the bottom of the groundwater. These observatories cover different climatic and physiographic characteristics over the country, providing information over a climate and eco-hydrologic transect connecting the Mediterranean to the Alps. With specific initial scientific questions, monitoring strategies, databases, and modeling activities, the WATZON observatories and sites is well representative of the heterogeneity of the critical zone and of the scientific communities studying it. Despite this diversity, all WATZON sites share a common eco-hydrologic monitoring and modelling program with three main objectives: 1) assessing the description of water mixing process across the critical zone by using integrated high-resolution isotopic, geophysical and hydrometeorological measurements from point to catchment scale, under different physiographic conditions and climate forcing; 2) testing water exchange mechanisms between subsurface reservoirs and vegetation, and assessing ecohydrological dynamics in different environments by coupling the high-resolution data set from different critical zone study sites of the initiative with advanced ecohydrological models at multiple spatial scales; 3) developing a process-based conceptual framework of ecohydrological processes in the critical zone to translate scientific knowledge into evidence to support policy and management decisions concerning water and land use in forested and agricultural ecosystems. This work provides an overview of the WATZON network, its objectives, scientific questions, and data management, with a specific focus on existing initiatives for linking data and models based on WATZON data

Assessing root water uptake transit time by simulating isotope transport in Hydrus-1D

Stable isotopes (2H and 18O) are common natural tracers for the investigation of water transport in the soil-plant-atmosphere continuum. Isotopic data can be coupled with soil water content data to inversely estimate soil hydraulic and transport parameters. The calibration of a hydrological model by inverse modelling is a prerequisite to determine the temporal origin of xylem water taken by roots. In this study, we used isotopic data to calibrate Hydrus-1D via inverse modelling to simulate one-dimensional water flow and isotope transport in a controlled soil-plant-atmosphere system. We propose the following protocol i) to estimate root water uptake transit time of irrigation water, and ii) to assess the sensitivity of the transit time distribution to the variation in the water available for root uptake. The dataset was obtained from an isotope-tracing experiment carried out between May and July 2018 on an olive tree placed in a pot inside a glasshouse. Meteorological variables and sap flow were monitored at 5-minute intervals, whereas shallow soil moisture (0-6 cm depth) was measured manually with an impedance probe at the daily timescale. The olive tree was irrigated with water of known isotopic composition. The pot surface was covered by a plastic sheet to avoid evaporation. Soil at different depths, twigs, wood cores and root samples were collected weekly for isotopic analyses. Water from soil and the xylem tissues was extracted by cryogenic vacuum distillation. Based on the results of a previous study carried out on the same dataset, we considered that no isotopic fractionation occurred during the water uptake and the transport within the olive tree. We used soil water content and δ18O data at different soil depths to optimize flow (soil hydraulic and root water uptake parameters) and transport (longitudinal dispersivity) parameters. Numerical simulations of isotope transport were validated with sap flow data (compared to actual transpiration) and δ18O in xylem water. Given that the timing of irrigation water for plant transpiration is fundamental for assessing the vulnerability of olive trees to drought, we will be proposing various scenarios based on different irrigation events to mimic drought periods. Based on these scenarios, we will be evaluating the sensitivity of the root water uptake transit time to the different water availability in the soil profile. Afterwards, the same protocol will be exploited to determine the root water uptake transit time for different tree species under various environmental conditions