Calibration and response of an agarose gel based passive sampler to record short pulses of aquatic organic pollutants

publisher: Elsevier articletitle: Calibration and response of an agarose gel based passive sampler to record short pulses of aquatic organic pollutants journaltitle: Talanta articlelink: http://dx.doi.org/10.1016/j.talanta.2016.12.010 content_type: article copyright: © 2016 Elsevier B.V. All rights reserved

Near-surface distribution of pollutants in coastal waters as assessed by novel polyethylene passive samplers

We report a novel and inexpensive method to provide high resolution vertical measurements of temporally integrated organic contaminants in surface and sub-surface waters in polluted coastal environments. It employs a strip of polyethylene deployed as a passive sampler. Verifications are confirmed via conventional spot sample analyses and against Performance Reference Compound (PRC) calibration methods. Analytes targeted include 16 Polycyclic Aromatic Hydrocarbons, 15 personal care products, 8 organophosphorus flame retardants, 4 antifouling ‘booster’ biocides and 15 n-alkanes. Whilst all contaminants typically revealed homogeneous concentrations from 10 cm to 3 m depth in the selected harbour (< 30% variations), many increased sharply at the air-sea interface. The passive sampler was shown to afford better resolution than could be achieved using conventional analytical techniques at the surface microlayer (SML). Whilst hydrophobicity appeared to be a key factor for the enrichment of many determinants, less correlation was found for the emerging contaminants. © 2017 Elsevier Lt

Penicillin susceptibility among invasive MSSA infections: a multicentre study in 16 Spanish hospitals

Objectives: To determine the prevalence of penicillin susceptibility among MSSA causing bloodstream infections (BSIs) in 16 Spanish hospitals and to characterize the penicillin-susceptible MSSA (MSSA-PENS) isolates. Methods: A total of 1011 Staphylococcus aureus isolates were collected from blood cultures in 16 Spanish hospitals during 2018–19 (6–12 months) and their susceptibility to 18 antimicrobials was determined. The MSSA-PENS isolates were selected and examined by PCR to determine the presence of the blaZ gene, other resistance genes and the genes lukF/lukS-PV, eta, etb and tst. The immune evasion cluster (IEC) type was also analysed. All the MSSA-PENS isolates were submitted to S. aureus protein A (spa) typing and the clonal complexes (CCs) were assigned according to their spa type. Results: The prevalence of MSSA was 74.6% (754/1011) and 14.9% (151/1011) were MSSA-PENS-blaZnegative. MSSA-PENS-blaZnegative isolates (n = 151) were ascribed to 88 spa types and 11 CCs. The most frequent CCs were CC5 (35/151) and CC398 (25/151), with t002-CC5 and t571-CC398 being the most common lineages. Pan-susceptibility was identified in 117 of the 151 MSSA-PENS-blaZnegative isolates (77.5%). In the remaining isolates, erythromycin and clindamycin resistance was the most frequent resistance found, although tobramycin, ciprofloxacin, fusidic acid, mupirocin and/or tetracycline resistance was also detected. Thirty-eight MSSA-PENS-blaZnegative isolates were IEC negative and four isolates were Panton–Valentine leucocidin (‘PVL’) positive. Conclusions: A high penicillin susceptibility rate was detected among MSSA, opening therapeutic opportunities for BSIs. The emergence of new successful MSSA-PENS clones could be responsible for these data. The detection among MSSA-PENS-blaZnegative isolates of the clonal lineage CC398 or the absence of an IEC raises questions about their possible animal origin, requiring further analysis

A new role for green leaf volatile esters in tomato stomatal defense against Pseudomonas syringe pv. tomato

[EN] The volatile esters of (Z)-3-hexenol with acetic, propionic, isobutyric, or butyric acids are synthesized by alcohol acyltransferases (AAT) in plants. These compounds are differentially emitted when tomato plants are efficiently resisting an infection with Pseudomonas syringae pv. tomato. We have studied the defensive role of these green leaf volatile (GLV) esters in the tomato response to bacterial infection, by analyzing the induction of resistance mediated by these GLVs and the phenotype upon bacterial infection of tomato plants impaired in their biosynthesis. We observed that treatments of plants with (Z)-3-hexenyl propionate (HP) and, to a greater extent with (Z)-3-hexenyl butyrate (HB), resulted in stomatal closure, PR gene induction and enhanced resistance to the bacteria. HB-mediated stomatal closure was also effective in several plant species belonging to Nicotiana, Arabidopsis, Medicago, Zea and Citrus genus, and both stomatal closure and resistance were induced in HB-treated NahG tomato plants, which are deficient in salicylic acid (SA) accumulation. Transgenic antisense AAT1 tomato plants, which displayed a reduction of ester emissions upon bacterial infection in leaves, exhibited a lower ratio of stomatal closure and were hyper-susceptible to bacterial infection. Our results confirm the role of GLV esters in plant immunity, uncovering a SA-independent effect of HB in stomatal defense. Moreover, we identified HB as a natural stomatal closure compound with potential agricultural applications.This work was funded by Grant AICO/2017/048 from the Generalitat Valenciana and by Grant INNVAL10/18/005 from the Agencia Valenciana de la Innovacio (Spain). We would like to thank the Metabolomics Service of the IBMCP (Valencia, Spain), especially to Teresa Caballero for her excellent technical support in the VOCs quantification. We also thank Eduardo Moya for technical assistance.López-Gresa, MP.; Payá, C.; Ozáez-Martínez, M.; Rodrigo Bravo, I.; Conejero Tomás, V.; Klee, H.; Belles Albert, JM.... (2018). A new role for green leaf volatile esters in tomato stomatal defense against Pseudomonas syringe pv. tomato. Frontiers in Plant Science. 9:1-12. https://doi.org/10.3389/fpls.2018.01855S112

Prevalence and genetic characteristics of Staphylococcus aureus CC398 isolates from invasive infections in spanish hospitals, focusing on the livestock-independent CC398-MSSA clade

Background: Livestock-associated (LA)-CC398-MRSA is closely related to pigs, being unfrequently detected in human invasive infections. CC398-MSSA is emerging in human invasive infections in some countries, but genetic and epidemiological characteristics are still scarcely reported. Objectives: To determine the prevalence of Staphylococcus aureus (SA) CC398, both MRSA and MSSA, among blood cultures SA isolates recovered in Spanish hospitals located in regions with different pig-farming densities (PD) and characterize the recovered isolates. Methods: One thousand twenty-two SA isolates (761 MSSA, 261 MRSA) recovered from blood cultures during 6–12 months in 17 Spanish hospitals (2018–2019) were studied. CC398 lineage identification, detection of spa-types, and antibiotic resistance, virulence and human immune evasion cluster (IEC) genes were analyzed by PCR/sequencing. Results: Forty-four CC398-MSSA isolates (4.3% of SA; 5.8% of MSSA) and 10 CC398-MRSA isolates (1% of SA; 3.8% of MRSA) were detected. Eleven spa-types were found among the CC398-MSSA isolates with t571 and t1451 the most frequent spa-types detected (75%). Most of CC398-MSSA isolates were Immune-Evasion-Cluster (IEC)-positive (88.6%), tetracycline-susceptible (95.5%) and erythromycin/clindamycin–inducible-resistant/erm(T)-positive (75%). No statistical significance was detected when the CC398-MSSA/MSSA rate was correlated to PD (pigs/km2) (p = 0.108). On the contrary, CC398-MRSA isolates were all IEC-negative, predominately spa-t011 (70%), and the CC398-MRSA/MRSA rate was significantly associated to PD (p < 0.005). Conclusion: CC398-MSSA is an emerging clade in invasive infections in Spanish hospitals. CC398-MRSA (mostly t011) and CC398-MSSA (mostly t571 and t1451) show important differences, possibly suggesting divergent steps in host-adaptation evolutionary processes. While CC398-MRSA is livestock-associated (lacking IEC-system), CC398-MSSA seems to be mostly livestock-independent, carrying human-adaptation markers.

Editor's Choice - Assessment of International Outcomes of Intact Abdominal Aortic Aneurysm Repair over 9 Years

Background: Case mix and outcomes of complex surgical procedures vary over time and between regions. This study analyses peri-operative mortality after intact abdominal aortic aneurysm (AAA) repair in 11 countries over 9 years. Methods: Data on primary AAA repair from vascular surgery registries in 11 countries for the years 2005-2009 and 2010-2013 were analysed. Multivariate adjusted logistic regression analyses were carried out to adjust for variations in case mix. Results: A total of 83,253 patients were included. Over the two periods, the proportion of patients >= 80 years old increased (18.5% vs. 23.1%; p <.0001) as did the proportion of endovascular repair (EVAR) (44.3% vs. 60.6; p <.0001). In the latter period, 25.8% of AAAs were less than 5.5 cm. The mean annual volume of open repairs per centre decreased from 12.9 to 10.6 between the two periods (p <.0001), and it increased for EVAR from 10.0 to 17.1 (p <.0001). Overall, peri-operative mortality fell from 3.0% to 2.4% (p <.0001). Mortality for EVAR decreased from 1.5% to 1.1% (p <.0001), but the outcome worsened for open repair from 3.9% to 4.4% (p = .008). The peri-operative risk was greater for octogenarians (overall, 3.6% vs. 2.1%, p <.0001; open, 9.5% vs. 3.6%, p <.0001; EVAR, 1.8% vs. 0.7%, p <.0001), and women (overall, 3.8% vs. 2.2%, p <.0001; open, 6.0% vs. 4.0%, p <.0001; EVAR, 1.9% vs. 0.9%, p <.0001). Peri-operative mortality after repair of AAAs Conclusions: In this large international cohort, total peri-operative mortality continues to fall for the treatment of intact AAAs. The number of EVAR procedures now exceeds open procedures. Mortality after EVAR has decreased, but mortality for open operations has increased. The peri-operative mortality for small AM treatment, particularly open surgical repair, is still considerable and should be weighed against the risk of rupture. (C) 2017 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.Peer reviewe

Hydrodynamics of fossil fishes

Fromtheir earliest origins, fishes have developed a suite of adaptations for locomotion in water, which determine performance and ultimately fitness. Even without data from behaviour, soft tissue and extant relatives, it is possible to infer a wealth of palaeobiological and palaeoecological information. As in extant species, aspects of gross morphology such as streamlining, fin position and tail type are optimized even in the earliest fishes, indicating similar life strategies have been present throughout their evolutionary history. As hydrodynamical studies become more sophisticated, increasingly complex fluid movement can be modelled, including vortex formation and boundary layer control. Drag-reducing riblets ornamenting the scales of fast-moving sharks have been subjected to particularly intense research, but this has not been extended to extinct forms. Riblets are a convergent adaptation seen in many Palaeozoic fishes, and probably served a similar hydrodynamic purpose. Conversely, structures which appear to increase skin friction may act as turbulisors, reducing overall dragwhile serving a protective function. Here,we examine the diverse adaptions that contribute to drag reduction in modern fishes and review the few attempts to elucidate the hydrodynamics of extinct forms

Common and Distinct Roles of Juvenile Hormone Signaling Genes in Metamorphosis of Holometabolous and Hemimetabolous Insects

Insect larvae metamorphose to winged and reproductive adults either directly (hemimetaboly) or through an intermediary pupal stage (holometaboly). In either case juvenile hormone (JH) prevents metamorphosis until a larva has attained an appropriate phase of development. In holometabolous insects, JH acts through its putative receptor Methoprene-tolerant (Met) to regulate Krüppel-homolog 1 (Kr-h1) and Broad-Complex (BR-C) genes. While Met and Kr-h1 prevent precocious metamorphosis in pre-final larval instars, BR-C specifies the pupal stage. How JH signaling operates in hemimetabolous insects is poorly understood. Here, we compare the function of Met, Kr-h1 and BR-C genes in the two types of insects. Using systemic RNAi in the hemimetabolous true bug, Pyrrhocoris apterus, we show that Met conveys the JH signal to prevent premature metamorphosis by maintaining high expression of Kr-h1. Knockdown of either Met or Kr-h1 (but not of BR-C) in penultimate-instar Pyrrhocoris larvae causes precocious development of adult color pattern, wings and genitalia. A natural fall of Kr-h1 expression in the last larval instar normally permits adult development, and treatment with an exogenous JH mimic methoprene at this time requires both Met and Kr-h1 to block the adult program and induce an extra larval instar. Met and Kr-h1 therefore serve as JH-dependent repressors of deleterious precocious metamorphic changes in both hemimetabolous and holometabolous juveniles, whereas BR-C has been recruited for a new role in specifying the holometabolous pupa. These results show that despite considerable evolutionary distance, insects with diverse developmental strategies employ a common-core JH signaling pathway to commit to adult morphogenesis

Differential regulation of Knotted1-like genes during establishment of the shoot apical meristem in Norway spruce (Picea abies)

Establishment of the shoot apical meristem (SAM) in Arabidopsis embryos requires the KNOXI transcription factor SHOOT MERISTEMLESS. In Norway spruce (Picea abies), four KNOXI family members (HBK1, HBK2, HBK3 and HBK4) have been identified, but a corresponding role in SAM development has not been demonstrated. As a first step to differentiate between the functions of the four Norway spruce HBK genes, we have here analyzed their expression profiles during the process of somatic embryo development. This was made both under normal embryo development and under conditions of reduced SAM formation by treatment with the polar auxin transport inhibitor NPA. Concomitantly with the formation of an embryonic SAM, the HBK2 and HBK4 genes displayed a significant up-regulation that was delayed by NPA treatment. In contrast, HBK1 and HBK3 were up-regulated prior to SAM formation, and their temporal expression was not affected by NPA. Ectopic expression of the four HBK genes in transgenic Arabidopsis plants further supported similar functions of HBK2 and HBK4, distinct from those of HBK1 and HBK3. Together, the results suggest that HBK2 and HBK4 exert similar functions related to the SAM differentiation and somatic embryo development in Norway spruce, while HBK1 and HBK3 have more general functions during embryo development

The Red Radio Ring: a gravitationally lensed hyperluminous infrared radio galaxy at z=2.553 discovered through the citizen science project SpaceWarps

We report the discovery of a gravitationally lensed hyperluminous infrared galaxy (intrinsic LIR≈1013 L⊙) with strong radio emission (intrinsic L1.4 GHz≈1025WHz−1) at z=2.553. The source was identified in the citizen science project SpaceWarpsthrough the visual inspection of tens of thousands of iJKs colour composite images of luminous red galaxies (LRGs), groups and clusters of galaxies and quasars. Appearing as a partial Einstein ring (re≈3 arcsec) around an LRG at z=0.2, the galaxy is extremely bright in the sub-millimetre for a cosmological source, with the thermal dust emission approaching 1 Jy at peak. The redshift of the lensed galaxy is determined through the detection of the CO(3→2) molecular emission line with the Large Millimetre Telescope's Redshift Search Receiver and through [O iii] and Hα line detections in the near-infrared from Subaru/Infrared Camera and Spectrograph. We have resolved the radio emission with high-resolution (300-400 mas) eMERLIN L-band and Very Large Array C-band imaging. These observations are used in combination with the near-infrared imaging to construct a lens model, which indicates a lensing magnification of μ≈10. The source reconstruction appears to support a radio morphology comprised of a compact (<250 pc) core and more extended component, perhaps indicative of an active nucleus and jet or lob