Antibiotic resistance spread potential in urban wastewater effluents disinfected by UV/H2O2 process

Urban wastewater treatment plants (UWTPs) are among the main hotspots of antibiotic resistance (AR) spread into the environment and the role of conventional and new disinfection processes as possible barrier to minimise the risk for AR transfer is presently under investigation. Accordingly, the aim of this work was to evaluate the effect of an advanced oxidation process (AOP) (specifically UV/H2O2) on AR transfer potential. UV/H2O2 disinfection experiments were carried out on real wastewater samples to evaluate the: i) inactivation of total coliforms, Escherichia coli and antibiotic resistant E. coli as well as ii) possible removal of target antibiotic resistance genes (ARGs) (namely, blaTEM, qnrS and tetW). In particular, DNA was extracted from both antibiotic resistant E. coli bacterial cells (intracellular DNA), grown on selective culture media, and the whole water suspension (total DNA) collected at different treatment times. Polymerase chain reaction (PCR) assay was performed to detect the absence/presence of the selected ARGs. Real Time quantitative Polymerase Chain Reaction (qPCR) was used to quantify the investigated ARGs in terms of copiesmL(-1). In spite of the bacterial inactivation and a decrease of ARGs in intracellular DNA after 60min treatment, UV/H2O2 process was not effective in ARGs removal from water suspension (total DNA). Particularly, an increase up to 3.7×10(3)copiesmL(-1) (p>0.05) of blaTEM gene was observed in total DNA after 240min treatment, while no difference (p>0.05) was found for qnrS gene between the initial (5.1×10(4)copiesmL(-1)) and the final sample (4.3×10(4)copiesmL(-1)). On the base of the achieved results, the investigated disinfection process may not be effective in minimising AR spread potential into the environment. The death of bacterial cells, which results in DNA release in the treated water, may pose a risk for AR transfer to other bacteria present in the receiving water body

Learning from transgenics: Advanced gene editing technologies should also bridge the gap with traditional genetic selection

We highlight the importance of the mixed genetic approaches (classical and currents) to improve the social perception related to the GMOs acceptance. We pointed out that CRISPR/Cas9 events could carry DNA variability/rearrangements related to somaclonal variations or epigenetic changes that are independent from the editing per se. The transformation of single cells, followed by plant regeneration, is used to generate modified plants, transgenic or genome editing (CRISPR/Cas9). The incidence of undesirable somaclonal variations and/or epigenetic changes that might have occurred during in vitro multiplication and regeneration processes, must be carefully analyzed in replicates in field trials. One remarkable challenge is related to the time lapse that selects the modified elite genotypes, because these strategies may spend a variable amount of time before the results are commercialized, where in all the cases it should be take into account the genotype × environment interactions. Furthermore, this combination of techniques can create an encouraging bridge between the public opinion and the community of geneticists who are concerned with plant genetic improvement. In this context, either transgenesis or genomic editing strategies become complementary modern tools to facing the challenges of plant genetic improvement. Their applications will depend on case-by-case analysis, and when possible will necessary associate them to the schemes and bases of classic plant genetic improvement.How to cite: Arencibia A, D'Afonseca V, Chakravarthi M, et al. Learning from transgenics: Advanced gene editing technologies should also bridge the gap with traditional genetic selection. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.06.001 Keywords: CRISPR-Cas systems, DNA methylation, Epigenetics, Gene editing, Genetic improvement, Genome editing, Gmos, Mutagenesis, Somaclonal variants, Transgenesis, Transgenic technolog

Association and diffusion of Li+ in carboxymethylcellulose solutions with application to environmentally friendly Li-ion batteries: a combined Molecular Dynamics and NMR study

Carboxymethylcellulose (CMC) has been proposed as a polymeric binder for the electrodes in environmentally friendly Li-ion batteries. Its physical properties and interaction with Li+ ions in water are interesting from the point of view of electrode preparationprocessability in water is one of the main reasons for its environmental friendlinessbut also for its possible application in aqueous Li-ion batteries. We combine MD simulations and variable-time PFGSE-NMR spectroscopy to investigate Li+ transport in CMC-based solutions. Both simulation and experiment show that, at concentrations such that Li-CMC has a gel like consistency, the Li+ diffusion coefficient is still very close to that in water. These ions interact preferentially with CMC’s carboxylate groups, giving rise to a rich variety of coordination patterns. However, the diffusion of Li+ in these systems is essentially unrestricted, with a fast, nanosecond-scale exchange of the ions between CMC and the aqueous environment

Epigenetic diversity of clonal white poplar (<i>Populus alba</i> L.) populations: could methylation support the success of vegetative reproduction strategy?

The widespread poplar populations of Sardinia are vegetatively propagated and live in different natural environments forming large monoclonal stands. The main goals of the present study were: i) to investigate/measure the epigenetic diversity of the poplar populations by determining their DNA methylation status; ii) to assess if and how methylation status influences population clustering; iii) to shed light on the changes that occur in the epigenome of ramets of the same poplar clone. To these purposes, 83 white poplar trees were sampled at different locations on the island of Sardinia. Methylation sensitive amplified polymorphism analysis was carried out on the genomic DNA extracted from leaves at the same juvenile stage. The study showed that the genetic biodiversity of poplars is quite limited but it is counterbalanced by epigenetic inter-population molecular variability. The comparison between MspI and HpaII DNA fragmentation profiles revealed that environmental conditions strongly influence hemi-methylation of the inner cytosine. The variable epigenetic status of Sardinian white poplars revealed a decreased number of population clusters. Landscape genetics analyses clearly demonstrated that ramets of the same clone were differentially methylated in relation to their geographic position. Therefore, our data support the notion that studies on plant biodiversity should no longer be restricted to genetic aspects, especially in the case of vegetatively propagated plant species

Arbuscular mycorrhizal fungi as a tool to ameliorate the phytoremediation potential of poplar: biochemical and molecular aspects

Poplar is a suitable species for phytoremediation, able to tolerate high concentrations of heavy metals (HMs). Arbuscular mycorrhizal fungi (AMF) form symbiotic associations with the roots of most land plants; they improve nutrient uptake and enhance phytoextraction of HMs while alleviating stress in the host plant. This review summarizes previous results from field and greenhouse studies conducted by us and dealing with this topic. In a field trial on a highly Zn- and Cu-contaminated site, differences in plant survival and growth were observed among 168 clones originating from natural populations of Populus alba L. and Populus nigra L. from northern Italy. After two and a half years from planting, the density, activity and metabolic versatility of the culturable fraction of the soil bacteria in the HM-polluted field was higher in the soil close to where larger poplar plants were growing, in spite of comparable HM concentrations recorded in these soils. One well-performing clone of P. alba (AL35), which accumulated a higher concentration of both metals and had high foliar polyamine (PA) levels, was used for further investigation. In a greenhouse study, AL35 cuttings pre-inoculated with AMF (Glomus mosseae or Glomus intraradices) and then transferred to pots containing soil, collected from the HM-polluted site, displayed growth comparable to that of controls grown on unpolluted soil, in spite of higher Cu and Zn accumulation. Such plants also showed an overall up-regulation of metallothionein (MT) and PA biosynthetic genes, together with increased PA levels. A genome-wide transcriptomic (cDNA-AFLP) analysis allowed the identification of a number of genes, mostly belonging to stress-related functional categories of defense and secondary metabolism, that were differentially regulated in mycorrhizal vs. non mycorrhizal plants. A proteomic analysis revealed that, depending on sampling time, changes in protein profiles were differentially affected by AMF and/or HMs. It is concluded that soil-borne microorganisms affect plant performance on HM-polluted soil. In particular, mycorrhizal plants exhibited increased capacity for phytostabilization of HMs, together with improved growth. Their greater stress tolerance may derive from the protective role of PAs, and from the strong modulation in the expression profiles of stress-related genes and proteins

Multiple points of view of heteronuclear NOE: long range vs short range contacts in pyrrolidinium based ionic liquids in the presence of Li salts.

The nuclear Overhauser enhancement (NOE) is a powerful tool of NMR Spectroscopy extensively used to gain structural information in ionic liquids (ILs). A general model for the distance dependence of intermolecular NOE in ILs was recently proposed showing that NOE spots beyond the first solvation shell and accounts for long-range effects. This conclusion prompted for a deep rethinking of the NOE data interpretation in ILs. In this paper we present an extensive and quantitative study of N-propyl-N-methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR13TFSI), the homologue with bis(fluorosulfonyl)imide (PYR13FSI), and their mixtures with LiTFSI based on {1H-19F} and {1H-7Li}NOE correlation experiments (HOESY). The former is mainly tuned on long-range interactions, the latter on short-range ones, due to the small and large Larmor frequency differences of the involved nuclei. The collected data are discussed in two different way: long-range {1H-19F}NOEs spot on the polar/apolar domains within the ILs, whereas short-range (e.g. regarding the first coordination shell) {1H-7Li}NOEs describe the contacts between first neighbors, with interesting correlation with the distances’ statistics derived by crystallographic data of related systems

Relationships between Seminal Plasma Metabolites, Semen Characteristics and Sperm Kinetics in Donkey (Equus asinus)

This study aimed to evaluate donkey seminal plasma metabolites and relate this information to the main characteristics of sperm quality. Sperm kinetics from 10 donkey stallions were analyzed with a computerized system at the time of collection (T0) and after 24 h storage at 4 °C (T24). Seminal plasma was frozen at -80 °C for subsequent proton nuclear magnetic resonance (1H NMR) spectroscopy. On three stallions, semen collection was repeated monthly for three times and sperm analysis also included mitochondrial activity and oxidative status. One stallion was azoospermic and a second semen collection was performed after one month. In the seminal plasma, 17 metabolites were identified; their levels showed numerous significant variations between the azoospermic and the normospermic individuals and grouped in well-defined clusters in a multivariate analysis. Comparing individuals with high and low sperm motility, the only discriminating metabolite was phenylalanine, whose levels were lower in the latter, as in the azoospermic individual. Phenylalanine was also the only metabolite highly correlated with all sperm kinematic parameters at T24. In conclusion, the present study has provided relevant information on the chemical characteristics of donkey semen, identified relationships between seminal metabolites, semen parameters, and sperm kinetics, and offered insights for future technological applications

The rat glucocorticoid receptor integration in Nicotiana langsdorffii genome affects plant responses to abiotic stresses and to arbuscular mycorrhizal symbiosis

The present study reports evidence of the pleiotropic effects caused by the insertion of the rat glucocorticoid receptor (GR) into the genome of Nicotiana langsdorffii. Transgenic N. langsdorffii-GR plants and the wild-type genotypes were analysed for their phenotypic and physiological characteristics. The integration of the GR gene affected flowering, growth habit, leaf morphology and stomatal pattern. Furthermore, GR plants showed an increased tolerance to heavy metal, drought and heat stress as evidenced by electrolyte leakage and by cell dedifferentiation and differentiation capability after recovery from stress treatments. We also monitored the establishment of the beneficial symbiosis between transgenic plants and the mycorrhizal fungus Funneliformis mosseae whose presymbiotic growth was significantly reduced by root exudates of N. langsdorffii-GR plants. The observed pleiotropic responses of transgenic plants may be a consequence of the hormonal imbalance, putatively due to the interaction of the GR receptor with the host genetic background. Our findings suggest that N. langsdorffii-GR plants can be used as a functional model system for the study of plant responses to a series of environmental stimuli

Primary squamous cell carcinoma of the liver: an unexpected pathological finding

Abstract Background Primary squamous cell carcinoma of the liver is a very rare cancer requiring a complete diagnostic investigation, as it presents some differences from other primary hepatic malignancies. We describe the case of an elderly patient with primitive squamous cell carcinoma of the liver treated by percutaneous microwave ablation and transarterial chemoembolization. Case presentation Although the pathogenesis remains uncertain, a possible transformation of the biliary epithelium caused by chronic inflammation or metaplasia and subsequent malignant transformation of preexisting benign hepatic cysts has been suggested. A critical review of the existing literature was performed by focusing on the pathogenesis, clinical presentation, and the suggested therapeutic strategies. Conclusion A multidisciplinary approach is needed to face rare hepatic malignancies where there are no clear guidelines