Bacterial biofilms on medical masks disposed in the marine environment: a hotspot of biological and functional diversity.

The present paper was aimed at investigating the role of disposable medical masks as a substrate for microbial biofilm growth and for the selection of specific microbial traits in highly impacted marine environments. In this view, we have immerged masks in a coastal area affected by a continuous input of artisanal fishery wastes and hydrocarbons pollution caused by intense maritime traffic. Masks maintained one month in the field were colonized by a bacterial community significantly different from that detected in the natural matrices from the same areas (seawater and sediments). The masks served as a viable substrate for the growth and enrichment of phototrophic microorganisms (Oxyphotobacteria), as well as Ruminococcaceae, Gracilibacteria, and Holophageae. In a follow-up investigation, masks previously colonized in the field were transferred in lab-scale microcosms which were supplemented with hydrocarbons and which contained also a piece of a virgin mask. After one month, a shift in the community composition, likely triggered by hydrocarbons addition, was observed in the previously colonized mask, with signatures characteristic of hydrocarbon-degrading microbial groups. Such hydrocarbon-degrading bacteria were also found to colonize the virgin mask. Remarkably, SEM micrographs provided indications of the occurrence of morphological modifications of the surface components of the virgin masks colonized by hydrocarbonoclastic bacteria. Overall, for the first time, we have demonstrated the potential risk for human and animal health determined by the uncorrected disposal of masks which are suitable substrates for pathogens colonization, permanence and spreading. Moreover, we have herein strengthened the knowledge on the role of hydrocarbon-degrading bacteria in the colonization and modification of fossil-based plastics in marine environment.

Environmental DNA metabarcoding for benthic monitoring: A review of sediment sampling and DNA extraction methods.

Environmental DNA (eDNA) metabarcoding (parallel sequencing of DNA/RNA for identification of whole communities within a targeted group) is revolutionizing the field of aquatic biomonitoring. To date, most metabarcoding studies aiming to assess the ecological status of aquatic ecosystems have focused on water eDNA and macroinvertebrate bulk samples. However, the eDNA metabarcoding has also been applied to soft sediment samples, mainly for assessing microbial or meiofaunal biota. Compared to classical methodologies based on manual sorting and morphological identification of benthic taxa, eDNA metabarcoding offers potentially important advantages for assessing the environmental quality of sediments. The methods and protocols utilized for sediment eDNA metabarcoding can vary considerably among studies, and standardization efforts are needed to improve their robustness, comparability and use within regulatory frameworks. Here, we review the available information on eDNA metabarcoding applied to sediment samples, with a focus on sampling, preservation, and DNA extraction steps. We discuss challenges specific to sediment eDNA analysis, including the variety of different sources and states of eDNA and its persistence in the sediment. This paper aims to identify good-practice strategies and facilitate method harmonization for routine use of sediment eDNA in future benthic monitoring.

Expanding ecological assessment by integrating microorganisms into routine freshwater biomonitoring.

Bioindication has become an indispensable part of water quality monitoring in most countries of the world, with the presence and abundance of bioindicator taxa, mostly multicellular eukaryotes, used for biotic indices. In contrast, microbes (bacteria, archaea and protists) are seldom used as bioindicators in routine assessments, although they have been recognized for their importance in environmental processes. Recently, the use of molecular methods has revealed unexpected diversity within known functional groups and novel metabolic pathways that are particularly important in energy and nutrient cycling. In various habitats, microbial communities respond to eutrophication, metals, and natural or anthropogenic organic pollutants through changes in diversity and function. In this review, we evaluated the common trends in these changes, documenting that they have value as bioindicators and can be used not only for monitoring but also for improving our understanding of the major processes in lotic and lentic environments. Current knowledge provides a solid foundation for exploiting microbial taxa, community structures and diversity, as well as functional genes, in novel monitoring programs. These microbial community measures can also be combined into biotic indices, improving the resolution of individual bioindicators. Here, we assess particular molecular approaches complemented by advanced bioinformatic analysis, as these are the most promising with respect to detailed bioindication value. We conclude that microbial community dynamics are a missing link important for our understanding of rapid changes in the structure and function of aquatic ecosystems, and should be addressed in the future environmental monitoring of freshwater ecosystems.

Dissolved organic matter in a tropical saline-alkaline lake of the East African Rift Valley.

Saline-alkaline lakes of the East African Rift are known to have an extremely high primary production supporting a potent carbon cycle. To date, a full description of carbon pools in these lakes is still missing. More specifically, there is not detailed information on the quality of dissolved organic matter (DOM), the main carbon energy source for heterotrophs prokaryotes. We report the first exhaustive description of DOM molecular properties in the water column of a meromictic saline-alkaline lake of the East African Rift. DOM availability, fate and origin were studied either quantitatively, in terms of dissolved organic carbon (DOC) and nitrogen (DON) or qualitatively, in terms of optical properties (absorbance) and molecular characterization of solid-phase extracted DOM (SPE-DOM) through negative electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). DOM availability was high (DOC ∼ 8.1 mM in surface waters) and meromixis imprinted a severe quantitative and qualitative change on DOM pool. At the surface, DOM was rich in aliphatic and moderately in aromatic molecules and thus mirroring autochthonous microbial production together with photodegradation. At the bottom changes were extreme: DOC increased up to 5 times (up to 50 mM) and, molecular signature drifted to saturated, reduced and non-aromatic DOM suggesting intense microbial activity within organic sediments. At the chemocline, DOC was retained indicating that this interface is a highly reactive layer in terms of DOM processing. These findings underline that saline-alkaline lakes of the East African Rift are carbon processing hot spots and their investigation may broaden our understanding of carbon cycling in inland waters at large.

Hydrological conditions control in situ DOM retention and release along a Mediterranean river.

Uncertainties exist regarding the magnitude of in situ dissolved organic matter (DOM) processing in lotic systems. In addition, little is known about the effects of extreme hydrological events on in-stream DOM retention or release during downriver transport. This study quantified the net in-stream retention/release efficiencies (η) of dissolved organic carbon (DOC) and its humic and protein-like fluorescent fractions along a Mediterranean river during drought, baseflow and flood conditions. High performance size exclusion chromatography was used to describe the apparent size distributions of the humic and protein-like DOM moieties. A snapshot mass balance allowed estimating the η values of DOC and humic and protein-like fractions. Significant DOM net retention (η < 0) was detected during the drought condition and the protein-like fraction was more retained than the humic-like fraction and bulk DOC. In addition, small substances were more efficiently retained than larger substances. DOC retention decreased under baseflow conditions, but it remained significant. The humic and protein-like net efficiencies exhibited high variability, but the net retention were not significant. From a longitudinal perspective, the entire fluvial corridor contributed net retention of DOC and humic and protein-like moieties net retention during drought condition. In contrast, net retention/release efficiencies exhibited spatial variability during baseflow condition. The flood preferentially mobilized large size DOM molecules and the fluvial corridor behaved as a homogeneous passive DOM (η = 0) conduit. This research highlights the relevance of hydrological extreme events on the magnitude of DOM retention/release mass balance and emphasizes the need to perform measurements during these conditions to quantify the impact of fluvial corridors on DOM fate and transport.

[The cardiological evaluation in patients undergoing to Day Surgery: when is indicated]. / La consulenza cardiologica nei pazienti da sottoporre ad intervento chirurgico in regime di Day Surgery: quando è indicate.

AIM: Guidelines established preoperative cardiac management of the patient undergoing non-cardiac surgery in hospitalization. Regarding the patients undergoing the surgery in DS, the management is not defined. Aim of this study was to evaluate the appropriateness of the cardiological consultation requested by the patients undergoing surgery with this method. MATERIALS AND METHODS: We examined the request of cardiological evaluation for patient admitted to DS of Sant'Andrea Hospital in Rome. We have considered: age, sex, clinic history, simpthomatology, electrocardiogram, cardiovascular objectivity, hemodynamic stability, comorbidity, therapy, type of the surgery, the motivation of the request. RESULTS: Of 2350 patients, 495 patients (21%) have been undergone the preoperative cardiologic consultation. The request was resulted as unnecessary for 432 (87.2%) patients, appropriate for 63 (12.7%): 4 that had the ischemic heart disease without knowing this, 6 with severe hypertension; 2 with mitral valve prolapse and valvular regurgitation; 34 with congestive heart failure; 6 with the alterations in EKG : 3 with "Brugada pattern"; 1 with Pace Maker (PMK) that had to be reprogrammed before the operation; 3 under dual antiplatelet therapy; 7 that were taking the oral anticoagulant therapy. Cardiac complications occurred just in one case with patient suffering dilated cardiomyopathy, diabetes and hypertension; during the cataract surgery was presented the abrupt increase of blood pressure and left ventricular failure. CONCLUSIONS: Preoperative cardiologic evaluation results as useless in most patients. However, in some particular situations had allowed the diagnosis of heart disease for the patients who did not know to have it.

Groundwater geochemistry and microbial community structure in the aquifer transition from volcanic to alluvial areas.

Groundwaters may act as sinks or sources of organic and inorganic solutes, depending on the relative magnitude of biochemical mobilizing processes and groundwater-surface water exchanges. The objective of this study was to link the lithological and hydrogeological gradients to the aquatic microbial community structure in the transition from aquifer recharge (volcanic formations) to discharge areas (alluvial deposits). A field-scale analysis was performed along a water table aquifer in which volcanic products decreased in thickness and areal extension, while alluvial deposits became increasingly important. We measured the main groundwater physical parameters and the concentrations of major and trace elements. In addition, the microbial community structure was assessed by estimating the occurrence of total coliforms and Escherichia coli, the prokaryotic abundance, the cytometric and phylogenetic community composition. The overall biogeochemical asset differed along the aquifer flow path. The concentration of total and live prokaryotic cells significantly increased in alluvial waters, together with the percentages of Beta- and Delta-Proteobacteria. The microbial propagation over a theoretical groundwater travel time allowed for the identification of microbial groups shifting significantly in the transition between the two different hydrogeochemical facies. The microbial community structure was intimately associated with geochemical changes, thus it should be further considered in view of a better understanding of groundwater ecology and sustainable management strategies.

Response of biofilm bacterial communities to antibiotic pollutants in a Mediterranean river.

Antibiotics are emerging contaminants, which wing to their bioactivity, may lead to short-term and long-term alterations of natural microbial communities in aquatic environment. We investigated the effects of antibiotics on biofilm bacterial communities in the Llobregat River (Northeast Spain). Three sampling sites were selected: two less polluted sites and one hotspot. River water was collected from each site and used both as inoculum and medium for growing biofilms in independent mesocosms. After 25d of biofilm colonization, we exposed the colonized biofilms to river waters from the downstream sites (progressively contaminated by antibiotics). A control from each site was maintained where the growing biofilm was always exposed to water from the same site. The bacterial community composition, bacterial live/dead ratio and extracellular enzyme activities of the biofilms were measured before and 9d after exposing the biofilms to increasing contaminated waters. Sixteen antibiotic compounds were detected in the water from the three sampling sites. At each site, the antibiotics present in the highest concentrations were sulfonamides, followed by quinolones and macrolides. Bacterial communities of biofilms grown with the three river waters differed markedly in their structure, but less so in terms of functional descriptors. After switching the medium water to increasing pollution, biofilms exhibited increased levels of actinobacteria (HGC), a trend that was associated to the higher antibiotic concentrations in the water. These biofilms also showed increased bacterial mortality, and decreased extracellular leucine-aminopeptidase and alkaline phosphatase. There was a significant correlation between antibiotic concentrations and biofilm responses. Our results indicate that the continuous entrance of antibiotics in running waters cause significant structural and functional changes in microbial attached communities.

Can the association of Ciclosporine A and Methotrexate maintain remission/low disease activity induced by etanercept in early Rheumatoid Arthritis patients? Evaluation by Magnetic Resonance Imaging.

The opportunity to induce remission/low disease activity in Rheumatoid Arthritis (RA) patients has been achieved in recent years by the adoption of more sensitive diagnostic methods [Magnetic Resonance Imaging (MRI), ultrasonography] and early aggressive treatments (combination of biologics and synthetic DMARDs). On the other hand, data are still scarce and contrasting about the management of long-term remission. The aim of this preliminary study is to evaluate whether the association of Methotrexate + Ciclosporine A (MTX + CSA) therapy in early RA (eRA) patients is able to maintain remission/low disease activity and avoid structural progression, evaluated by MRI. Etanercept was suspended in patients who reached remission/low disease activity and CSA+MTX therapy was introduced (T0), all patients continued to receive MTX; at this time MRI showed mild/moderate synovitis and erosions in all the patients; 1-year after (T1), a slight reduction in mean synovitis, bone edema and total score was observed, whereas the erosion score was unchanged. The mean DAS44 remained stable from T0 to T1 and 6/7 patients maintained a low disease activity score. No side effects were reported. These results confirm the good clinical efficacy and safety of the combination therapy CSA+MTX in eRA patients and demonstrate a parallel arrest of structural damage evaluated by MRI 1-year after etanercept suspension.

Petroclival meningioma mimicking the presentation of a transient ischemic attack.

A case of petroclival meningioma with pseudo-vascular clinical feature, documented by magnetic resonance imaging, is described. The location of the tumor and the persistent normality of the clinical examination excluded any surgical attempt. Such transient neurological symptoms in case of posterior fossa meningiomas have been seldom reported. Attempts for a physiological explanation are considered.

Cavernomas of the spinal cord: report of two patients.

Two operated cases of spinal cord cavernomas are presented. Since spinal angiography is usually normal and myelography not specific, the contribution of magnetic resonance imaging to the diagnosis is emphasized. Surgical considerations of treatment are discussed.

[Study of basal rhythms in normal and pathologic subjects by EEG mapping]. / Etude des rythmes de base chez le sujet normal et pathologique par la cartographie EEG.

The topography of basic EEG rhythms brings a new dimension to our understanding of normal and pathologic electrogenesis in the brain. But our experience has shown that it is valuable to make use of the numeric spectral data in order to best decide which rhythms should be mapped. This study demonstrates that quantification of basic EEG rhythms is valuable, not only for beta activity in pharmacology or as an aid for the diagnosis and localization of epilepsy (as has been reported in the literature), but for the other rhythms as well. Our experience to date suggests that EEG rhythms be divided into two major groups: 1) occipital rhythms of extremely variable power which have a peak frequency equal to or greater than 8 Hz and which react to eye opening and 2) parietal-central rhythms which have a frequency equal to or less than 7.5 Hz and which are unreactive to eye opening. Alteration of these characteristics may occur as a result of widely different types of pathology but are usually not visible in the traditional EEG.