Nanosilver impacts on aquatic microbial decomposers and litter decomposition assessed as pollution-induced community tolerance (PICT)

The growing proliferation of silver nanoparticles (AgNPs) calls for detailed information on ecotoxicological effects, particularly on diverse communities and key ecosystem processes where impacts remain poorly known. This includes the decomposition of plant litter by fungi and bacteria in streams. Impacts are likely to depend on community composition, because species vary in their sensitivities to stressors. Therefore, our goal was to determine if shifts in microbial communities triggered by chronic exposure to low concentrations of nano (<200 μg L−1) and ionic (20 μg L−1) silver increase community tolerance to these contaminants, as described in the pollution-induced community tolerance (PICT) concept. We used stream microbial decomposers associated with leaf litter in microcosms to assess the applicability of this concept by determining tolerance acquisition towards AgNP and ionic Ag in short-term inhibition assays. Endpoints included fungal sporulation, bacterial production, microbial respiration and the potential activity of a protein-degrading enzyme, leucine aminopeptidase. Analyses of microbial communities showed that chronic exposure to the highest AgNP concentrations led to similar communities, and that these were distinct from the control communities. Most important, chronic exposure of fungi and bacteria to both AgNP and ionic Ag also increased tolerance of the microbes, as revealed by notably reduced adverse effects on bacterial production. Overall, our results demonstrate the usefulness of applying the PICT concept to litter decomposers and decomposition as an approach to assess the risks posed by nano and ionic silver to freshwater ecosystems.This work was supported by the Swiss National Science Foundation (SNF, 200020_134750/1) as part of the National Research Programme NRP 64 on Opportunities and Risks of Nanomaterials, the German Academic Exchange Service (DAAD, 57036658), FEDER-POFC-COMPETE, the Portuguese Foundation for Science and Technology (PTDC/BIA-BMA/ 30922/2017, FCT-DAAD 2013-2014), and a PhD fellowship to D. B. (SFRH/BD/88181/2012)

A cost effectiveness analysis of salt reduction policies to reduce coronary heart disease in four Eastern Mediterranean countries.

BACKGROUND: Coronary Heart Disease (CHD) is rising in middle income countries. Population based strategies to reduce specific CHD risk factors have an important role to play in reducing overall CHD mortality. Reducing dietary salt consumption is a potentially cost-effective way to reduce CHD events. This paper presents an economic evaluation of population based salt reduction policies in Tunisia, Syria, Palestine and Turkey. METHODS AND FINDINGS: Three policies to reduce dietary salt intake were evaluated: a health promotion campaign, labelling of food packaging and mandatory reformulation of salt content in processed food. These were evaluated separately and in combination. Estimates of the effectiveness of salt reduction on blood pressure were based on a literature review. The reduction in mortality was estimated using the IMPACT CHD model specific to that country. Cumulative population health effects were quantified as life years gained (LYG) over a 10 year time frame. The costs of each policy were estimated using evidence from comparable policies and expert opinion including public sector costs and costs to the food industry. Health care costs associated with CHDs were estimated using standardized unit costs. The total cost of implementing each policy was compared against the current baseline (no policy). All costs were calculated using 2010 PPP exchange rates. In all four countries most policies were cost saving compared with the baseline. The combination of all three policies (reducing salt consumption by 30%) resulted in estimated cost savings of $235,000,000 and 6455 LYG in Tunisia;$39,000,000 and 31674 LYG in Syria; $6,000,000 and 2682 LYG in Palestine and$1,3000,000,000 and 378439 LYG in Turkey. CONCLUSION: Decreasing dietary salt intake will reduce coronary heart disease deaths in the four countries. A comprehensive strategy of health education and food industry actions to label and reduce salt content would save both money and lives

Colloquium: Mechanical formalisms for tissue dynamics

The understanding of morphogenesis in living organisms has been renewed by tremendous progressin experimental techniques that provide access to cell-scale, quantitative information both on theshapes of cells within tissues and on the genes being expressed. This information suggests that ourunderstanding of the respective contributions of gene expression and mechanics, and of their crucialentanglement, will soon leap forward. Biomechanics increasingly benefits from models, which assistthe design and interpretation of experiments, point out the main ingredients and assumptions, andultimately lead to predictions. The newly accessible local information thus calls for a reflectionon how to select suitable classes of mechanical models. We review both mechanical ingredientssuggested by the current knowledge of tissue behaviour, and modelling methods that can helpgenerate a rheological diagram or a constitutive equation. We distinguish cell scale ("intra-cell")and tissue scale ("inter-cell") contributions. We recall the mathematical framework developpedfor continuum materials and explain how to transform a constitutive equation into a set of partialdifferential equations amenable to numerical resolution. We show that when plastic behaviour isrelevant, the dissipation function formalism appears appropriate to generate constitutive equations;its variational nature facilitates numerical implementation, and we discuss adaptations needed in thecase of large deformations. The present article gathers theoretical methods that can readily enhancethe significance of the data to be extracted from recent or future high throughput biomechanicalexperiments.Comment: 33 pages, 20 figures. This version (26 Sept. 2015) contains a few corrections to the published version, all in Appendix D.2 devoted to large deformation

Power-to-Hydrogen and Hydrogen-to-X pathways: opportunities for next generation energy systems

Energy systems are evolving rapidly around the world, driven mainly by CO2-e reduction targets. This has led to opportunities for integrated low carbon electricity-and-fuel systems founded on large scale “Power-to-Hydrogen, Hydrogen-to-X” (PtH-HtX). Power-to-Hydrogen (PtH) refers to large scale electrolysis. Hydrogen-to-X (HtX) refers to a range of high value products and services. If these pathways start with low-carbon electricity, then the fuel consumed at the downstream end also low-carbon. Use of intermittently low valued power lowers all production costs. This paper specifically identifies the main pathways and interconnections in a way that overcomes the ambiguities inherent in the term “Power-to-Gas”. In turn, this provides solid and easier to understand foundations for building legal and regulatory frameworks for new business opportunities along the lengths of the numerous pathways from supply to consumption.<br/

Combined cytogenetic and molecular methods for taxonomic verification and description of Brassica populations deriving from different origins

Agriculture faces great challenges to overcome global warming and improve system sustainability, requiring access to novel genetic diversity. So far, wild populations and local landraces remain poorly explored. This is notably the case for the two diploid species, Brassica oleracea L. (CC, 2n=2x=18) and B. rapa L. (AA, 2n=2x=20). In order to explore the genetic diversity in both species, we have collected populations in their centre of origin, the Mediterranean basin, on a large contrasting climatic and soil gradient from northern Europe to southern sub-Saharan regions. In these areas, we also collected 14 populations belonging to five B. oleracea closely related species. Our objective was to ensure the absence of species misidentification at the seedling stage among the populations collected and to describe thereafter their origins. We combined flow cytometry, sequencing of a species-specific chloroplast genomic region, as well as cytogenetic analyses in case of unexpected results for taxonomic verification. Out of the 112 B. oleracea and 154 B. rapa populations collected, 103 and 146, respectively, presented a good germination rate and eighteen populations were misidentified. The most frequent mistake was the confusion of these diploid species with B. napus. Additionally for B. rapa, two autotetraploid populations were observed. Habitats of the collected and confirmed wild populations and landraces are described in this study. The unique plant material described here will serve to investigate the genomic regions involved in adaptation to climate and microbiota within the framework of the H2020 Prima project ‘BrasExplor’

Novel sequence variations in LAMA2 andSGCG genes modulating cis-acting regulatory elements and RNA secondary structure

In this study, we detected new sequence variations in LAMA2 and SGCG genes in 5 ethnic populations, and analysed their effect on enhancer composition and mRNA structure. PCR amplification and DNA sequencing were performed and followed by bioinformatics analyses using ESEfinder as well as MFOLD software. We found 3 novel sequence variations in the LAMA2 (c.3174+22_23insAT and c.6085 +12delA) and SGCG (c. * 102A/C) genes. These variations were present in 210 tested healthy controls from Tunisian, Moroccan, Algerian, Lebanese and French populations suggesting that they represent novel polymorphisms within LAMA2 and SGCG genes sequences. ESEfinder showed that the c. * 102A/C substitution created a new exon splicing enhancer in the 3'UTR of SGCG genes, whereas the c.6085 +12delA deletion was situated in the base pairing region between LAMA2 mRNA and the U1snRNA spliceosomal components. The RNA structure analyses showed that both variations modulated RNA secondary structure. Our results are suggestive of correlations between mRNA folding and the recruitment of spliceosomal components mediating splicing, including SR proteins. The contribution of common sequence variations to mRNA structural and functional diversity will contribute to a better study of gene expression

A Mutation in Myo15 Leads to Usher-Like Symptoms in LEW/Ztm-ci2 Rats

The LEW/Ztm-ci2 rat is an animal model for syndromal deafness that arose from a spontaneous mutation. Homozygous animals show locomotor abnormalities like lateralized circling behavior. Additionally, an impaired vision can be observed in some animals through behavioral studies. Syndromal deafness as well as retinal degeneration are features of the Usher syndrome in humans. In the present study, the mutation was identified as a base substitution (T->C) in exon 56 of Myo15, leading to an amino acid exchange from leucine (Leu) to proline (Pro) within the carboxy-terminal MyTH4 domain in the proteins' tail region. Myo15 mRNA was expressed in the retina as demonstrated for the first time with the help of in-situ hybridization and PCR. To characterize the visual phenotype, rats were examined by scotopic and photopic electroretinography and, additionally, histological analyses of the retinas were conducted. The complete loss of sight was detected along with a severe degeneration of photoreceptor cells. Interestingly, the manifestation of the disease does not solely depend on the mutation, but also on environmental factors. Since the LEW/Ztm-ci2 rat features the entire range of symptoms of the human Usher syndrome we think that this strain is an appropriate model for this disease. Our findings display that mutations in binding domains of myosin XV do not only cause non-syndromic hearing loss but can also lead to syndromic disorders including retinal dysfunction

Finding New Genes for Non-Syndromic Hearing Loss through an In Silico Prioritization Study

At present, 51 genes are already known to be responsible for Non-Syndromic hereditary Hearing Loss (NSHL), but the knowledge of 121 NSHL-linked chromosomal regions brings to the hypothesis that a number of disease genes have still to be uncovered. To help scientists to find new NSHL genes, we built a gene-scoring system, integrating Gene Ontology, NCBI Gene and Map Viewer databases, which prioritizes the candidate genes according to their probability to cause NSHL. We defined a set of candidates and measured their functional similarity with respect to the disease gene set, computing a score () that relies on the assumption that functionally related genes might contribute to the same (disease) phenotype. A Kolmogorov-Smirnov test, comparing the pair-wise distribution on the disease gene set with the distribution on the remaining human genes, provided a statistical assessment of this assumption. We found at a p-value that the former pair-wise is greater than the latter, justifying a prioritization strategy based on the functional similarity of candidate genes respect to the disease gene set. A cross-validation test measured to what extent the ranking for NSHL is different from a random ordering: adding 15% of the disease genes to the candidate gene set, the ranking of the disease genes in the first eight positions resulted statistically different from a hypergeometric distribution with a p-value and a power. The twenty top-scored genes were finally examined to evaluate their possible involvement in NSHL. We found that half of them are known to be expressed in human inner ear or cochlea and are mainly involved in remodeling and organization of actin formation and maintenance of the cilia and the endocochlear potential. These findings strongly indicate that our metric was able to suggest excellent NSHL candidates to be screened in patients and controls for causative mutations

Contrasting cardiovascular mortality trends in Eastern Mediterranean populations: contributions from risk factor changes and treatments

Background Middle income countries are facing an epidemic of non-communicable diseases, especially coronary heart disease (CHD). We used a validated CHD mortality model (IMPACT) to explain recent trends in Tunisia, Syria, the occupied Palestinian territory (oPt) and Turkey. Methods Data on populations, mortality, patient numbers, treatments and risk factor trends from national and local surveys in each country were collated over two time points (1995–97; 2006–09); integrated and analysed using the IMPACT model. Results Risk factor trends: Smoking prevalence was high in men, persisting in Syria but decreasing in Tunisia, oPt and Turkey. BMI rose by 1–2 kg/m2 and diabetes prevalence increased by 40%–50%. Mean systolic blood pressure and cholesterol levels increased in Tunisia and Syria. Mortality trends: Age-standardised CHD mortality rates rose by 20% in Tunisia and 62% in Syria. Much of this increase (79% and 72% respectively) was attributed to adverse trends in major risk factors, occurring despite some improvements in treatment uptake. CHD mortality rates fell by 17% in oPt and by 25% in Turkey, with risk factor changes accounting for around 46% and 30% of this reduction respectively. Increased uptake of community treatments (drug treatments for chronic angina, heart failure, hypertension and secondary prevention after a cardiac event) accounted for most of the remainder. Discussion CHD death rates are rising in Tunisia and Syria, whilst oPt and Turkey demonstrate clear falls, reflecting improvements in major risk factors with contributions from medical treatments. However, smoking prevalence remains very high in men; obesity and diabetes levels are rising dramatically