The fate of conventional and potentially degradable gillnets in a seawater-sediment system.

Abandoned gillnets in the marine environment represent a global environmental risk due to the ghost fishing caused by the nets. Degradation of conventional nylon gillnets was compared to that of nets made of polybutylene succinate co-adipate-co-terephthalate (PBSAT) that are designed to degrade more readily in the environment. Gillnet filaments were incubated in microcosms of natural seawater (SW) and marine sediments at 20 °C over a period of 36 months. Tensile strength tests and scanning electron microscopy analyses showed weakening and degradation of the PBSAT filaments over time, while nylon filaments remained unchanged. Pyrolysis-gas chromatography/mass spectrometry revealed potential PBSAT degradation products associated with the filament surfaces, while nylon degradation products were not detected by these analyses. Microbial communities differed significantly between the biofilms on the nylon and PBSAT filaments. The slow deterioration of the PBSAT gillnet filaments shown here may be beneficial and reduce the ghost fishing periods of these gillnets.

Absolute quantification of priority bacteria in aquaculture using digital PCR.

Modern aquaculture systems are designed for intensive rearing of fish or other species. Both land-based and offshore systems typically contain high loads of biomass and the water quality in these systems is of paramount importance for fish health and production. Microorganisms play a crucial role in removal of organic matter and nitrogen-recycling, production of toxic hydrogen sulfide (H2S), and can affect fish health directly if pathogenic for fish or exerting probiotic properties. Methods currently used in aquaculture for monitoring certain bacteria species numbers still have typically low precision, specificity, sensitivity and are time-consuming. Here, we demonstrate the use of Digital PCR as a powerful tool for absolute quantification of sulfate-reducing bacteria (SRB) and major pathogens in salmon aquaculture, Moritella viscosa, Yersinia ruckeri and Flavobacterium psychrophilum. In addition, an assay for quantification of Listeria monocytogenes, which is a human pathogen bacterium and relevant target associated with salmonid cultivation in recirculating systems and salmon processing, has been assessed. Sudden mass mortality incidents caused by H2S produced by SRB have become of major concern in closed aquaculture systems. An ultra-sensitive assay for quantification of SRB has been established using Desulfovibrio desulfuricans as reference strain. The use of TaqMan® probe technology allowed for the development of multi-plex assays capable of simultaneous quantification of these aquaculture priority bacteria. In single-plex assays, limit of detection was found to be at around 20 fg DNA for M. viscosa, Y. ruckeri and F. psychrophilum, and as low as 2 fg DNA for L. monocytogenes and D. desulfuricans.

Attachment of APAM to mineral particles in seawater.

Polymer injection is used in enhanced oil recovery (EOR) when an oil field ages and the pressure in the reservoir decreases, or for oil fields with heavy oil. By polymer injection, the viscosity of the water injected for pressure support is increased by mixing with a high concentration of a polymer solution. Polymers used in EOR operations are often high molecular weight polyacrylamides, including anionic polyacrylamide (APAM), which may subsequently enter the marine environment with produced water releases. Since seawater (SW) contains mineral particles (MPs) in low concentrations, and polymers like APAM are known to flocculate MPs, we investigated if APAM at different concentrations (0.5-10 mg/L) would attach and flocculate MPs, when these occurred in concentrations relevant for oceanic SW (1 mg/L). Two types of MPs, diatomaceous earth and kaolin, were exposed to fluorescence-tagged APAM (APAM-TAG). A low-energy carousel system with natural seawater (SW) was used for incubation of MPs and APAM-TAG at a temperature relevant for the Norwegian Continental Shelf (13 °C). Attachment to MPs and aggregates of these were analysed by fluorometry and fluorescence microscopy. Particle analyses showed that only minor fractions of the MPs aggregated. When samples were separated in steel filter with a mesh size of 20 µm, APAM-TAG was mainly measured in the flow-through fraction (<20 µm), and the results therefore showed that the polymer mainly remained in the water-phase, or was attached to small particles (<20 µm). For the small fraction of APAM attaching to aggregated MPs, attraction to kaolin was higher than to diatomaceous earth, and fluorescence microscopy analyses confirmed the presence of fluorescent particles at the higher APAM concentrations. MPs at concentrations relevant for oceanic SW are therefore not expected to significantly contribute to sedimentation of APAM dissolved in the water column.

Interaction between microalgae, marine snow and anionic polyacrylamide APAM at marine conditions.

When an oil field ages and the pressure in the reservoir decreases, or for oil fields with heavy oil, there may be a need for enhanced oil recovery (EOR) technologies. Polymer injection is a water-based EOR method where the viscosity of the water injected for pressure support is increased by mixing with a high concentration polymer solution. In this project, the potential fate of a synthetic anionic polyacrylamide (APAM) in seawater was investigated, since these EOR polymers may enter the marine environment with the produced water (PW). The main objective of the study was to determine if the APAM will interact with cells or aggregates (marine snow) of microalgae, resulting in potential polymer transport from the euphotic zone to the seabed. Three different species of microalgae with different degree of autotrophy (autotroph, mixotroph and heterotroph) were exposed to fluorescence-tagged APAM. Attachment to algal cells or aggregates formed by active or heat-inactivated algae were analysed by fluorescence microscopy and fluorometry. Our results suggested that attachment of APAM to cells of the algal species included in his study was negligible. A carousel system with natural seawater (SW) was used for formation of algal aggregates, one of the key components of marine snow. When aggregates of the diatom Thalassiosira rotula were formed in the presence of the fluorescence-tagged APAM, and at SW temperatures relevant for the Norwegian Continental Shelf, the polymer was nearly exclusively measured in the water phase after separation from the aggregates. The aggregate measurements therefore confirmed the results from the attachment studies, and we found no evidence of accumulation of APAM in aggregates formed from algae. Marine snow from algae is therefore not expected to significantly contribute to sedimentation of APAM dissolved in the water column.

A single Legionella pneumophila genotype in the freshwater system in a ship experiencing three separate outbreaks of legionellosis in 6 years.

BACKGROUND: Recurrent legionella outbreaks at one and the same location are common. We have identified a single Legionella pneumophila genotype associated with recurrent Legionella outbreaks over 6 years. METHODS: Field emergency surveys following Legionella outbreaks were performed on a vessel in 2008, 2009 and 2013. Water samples from both the distribution and technical parts of the potable water system were analyzed with respect to L. pneumophila [Real-Time PCR, cultivation, serotyping and genotyping (PFGE)] and free-living amoebae, (FLA). RESULTS: Legionella pneumophila serogroup 1 was present in the ship's potable water system during every outbreak. Genotyping of the 2008 survey material showed two separate PFGE genotypes while those in 2009 and 2013 demonstrated the presence of only one of the two genotypes. FLA with intracellular L. pneumophila of the same genotype were also detected. Analyses of the freshwater system on a ship following three separate Legionella outbreaks, for L. pneumophila and FLAs, revealed a single L. pneumophila genotype and FLA (Hartmanella). CONCLUSIONS: It is reasonable to assume that the L. pneumophila genotype detected in the freshwater system was the causal agent in the outbreaks onboard. Persistence of an apparently low-pathogenic L. pneumophila genotype and FLA in a potable water system represent a potential risk for recurrent outbreaks.

Allergic diseases and the effect of inhaled epinephrine in children with acute bronchiolitis: follow-up from the randomised, controlled, double-blind, Bronchiolitis ALL trial.

BACKGROUND: Although use of inhaled bronchodilators in infants with acute bronchiolitis is not supported by evidence-based guidelines, it is often justified by the belief in a subgroup effect in individuals developing atopic disease. We aimed to assess if inhaled epinephrine during acute bronchiolitis in infancy would benefit patients with later recurrent bronchial obstruction, atopic eczema, or allergic sensitisation. METHODS: In the randomised, double-blind, multicentre Bronchiolitis ALL trial, 404 infants with moderate-to-severe acute bronchiolitis were recruited from eight hospitals in Norway to receive either inhaled epinephrine or saline up to every second hour throughout the hospital stay. Randomisation was done centrally, and the two study medications (20 mg/mL racemic epinephrine or 0.9% saline) were prepared in identical bottles. The dose given depended on the infant's weight: 0.10 mL, less than 5 kg; 0.15 mL, 5-6.9 kg; 0.2 mL, 7-9.9 kg; and 0.25 mL, 10 kg or more; all dissolved in 2 mL of 0.9% saline before nebulisation. The primary outcome was the length of hospital stay. In this follow-up study, 294 children were reinvestigated at 2 years of age with an interview, a clinical examination, and a skin prick test for 17 allergens, determining bronchial obstruction, atopic eczema, and allergic sensitisation, on which subgroup analyses were done. Analyses were done by intention to treat. The trial has been completed and is registered at ClinicalTrials.gov (number NCT00817466) and EUDRACT (number 2009-012667-34). FINDINGS: Length of stay did not differ between patients who received inhaled epinephrine versus saline in the subgroup of infants who developed recurrent bronchial obstruction by age 2 years (143 [48.6%] of 294 patients; p(interaction)=0.40). However, the presence of atopic eczema or allergic sensitisation by the age of 2 years (n=77) significantly interacted with the treatment effect of inhaled epinephrine (p(interaction)=0.02); the length of stay (mean 80.3 h, 95% CI 72.8-87.9) was significantly shorter in patients receiving inhaled epinephrine versus saline in patients without allergic sensitisation or atopic eczema by 2 years (-19.9 h, -33.1 to -6.3; p=0.003). No significant differences were found in length of hospital stay in response to epinephrine or saline in children with atopic eczema or allergic sensitisation by 2 years (+16.2 h, -11.0 to 43.3; p=0.24). INTERPRETATION: Contrary to our hypothesis, hospital length of stay for bronchiolitis was not reduced by administration of inhaled epinephrine in infants who subsequently developed atopic eczema, allergic sensitisation, or recurrent bronchial obstruction. The present study does not support an individual trial of inhaled epinephrine in acute bronchiolitis in children with increased risk of allergic diseases. FUNDING: Medicines for Children Network, Norway.

Legionella pneumophila in Norwegian naval vessels.

BACKGROUND: Little is known about the occurrence of Legionella pneumophila in water supply systems on board ships. Our aim was to study the occurrence of L. pneumophila in the water supply system on board Norwegian naval vessels as the basis for framing preventive strategies against Legionella infection. MATERIAL AND METHOD: Water samples were collected from technical installations and from the water distribution network on board 41 vessels and from ten water filling (bunkering) stations, the sampling taking place in two rounds separated by a one-year interval. The samples were subjected to analysis, including serotyping and genotyping, with a view to identifying the presence of L. pneumophila and of free-living amoebae. RESULTS: L. pneumophila was found in 20 out of a total of 41 vessels in the first round of sampling, and live L. pneumophila serogroup 1 was isolated in seven of the 20 vessels. Free-living amoebae were found in the water supply system in most of the vessels, including all the vessels with L. pneumophila. The same genotype of L. pneumophila was identified in the water in bunkering stations and in the water on board the vessels. INTERPRETATION: L. pneumophila was not present in all the vessels, but all the vessels where the bacterium was found were also contaminated with free-living amoebae. We have demonstrated the probability of the fresh water from bunkering stations being the source of the contamination. In framing preventive strategies, importance should therefore be attached to identifying the source of contamination and the presence of free-living amoebae, as a premise for the establishment and growth of L. pneumophila in onboard water supply systems.

[Patient satisfaction with two different types of bladder catheters]. / Pasienttilfredshet med to typer blaerekatetre.

BACKGROUND: The insertion of a urinary catheter may cause some discomfort or pain. This study was done in order to compare patient-perceived discomfort with two commonly used coated urinary catheters for in-out catheterisation. MATERIAL AND METHODS: A total of 196 women were randomised to be catheterised with one of two coated, hydrophilic catheters, either a Lofric or a SpeediCath catheter. Degree of discomfort was recorded on a 10 cm visual analogue scale. RESULTS AND INTERPRETATION: There was no difference in patient-perceived discomfort between the two catheters. The degree of discomfort was small with both catheters, with a median score of only 0.75 cm on the scale.

[Diagnosing allergic reactions to ingested wheat in children]. / Diagnostikk av reaksjon på hvete i maten hos barn.

BACKGROUND: Sensitisation to wheat demonstrated by specific IgE without clinical reactions to ingested wheat is common. Clinical allergy towards wheat may cause anaphylactic or mild reactions. Until now, oral challenge tests have been necessary for diagnosing severe reactions to ingested wheat. We wanted to distinguish between severe and mild reactions by using three different IgE tests against wheat. MATERIAL AND METHODS: 29 children with elevated levels of specific IgE against wheat (f4 test) were referred to our hospital for further diagnostic procedures. We performed specific IgE tests against different wheat components (f4, f79 and f98) and oral provocation tests. RESULTS: 10 children with severe clinical reactions had high levels at all three specific IgE tests and comparable levels between the tests. The 4 children with mild reactions showed varying values of IgE but very similar levels between the three different tests. 15 children had negative provocation tests, varying levels of specific IgE, and less similar levels between the tests. INTERPRETATION: Available specific IgE tests are not useful in order to distinguish between severe, mild or no clinical reactions to ingested wheat. Oral challenge tests are still needed for correct diagnosis of severe wheat allergy.

Selective iron supplementation based on serum ferritin values early in pregnancy: are the Norwegian recommendations satisfactory?

BACKGROUND: The aims of the present study were to evaluate the recommendations by comparing compliance and adequacy of iron status at 6 weeks postpartum between one group given advice only and one group given advice plus iron supplement. In the latter group the efficacies of two iron preparations of different strengths and types were compared. METHODS: Ninety-three women had been given advice only (Group I) and were enrolled in the project at 6 weeks postpartum. Two hundred and thirty-three women enrolled at their second antenatal visit and were given advice plus iron supplement; those with s-ferritin <60 microg/L were randomized to a daily dose of 1) 60 mg Fe2+ (Ferromax) or 2) 3.6 mg heme iron plus 24 mg Fe2+ (Hemofer), and started taking the supplement at once if s-ferritin <20 microg/L or at 20 weeks if 20-60 microg/L. In addition to hemoglobin as routine, s-ferritin was measured in all the women at 6 weeks postpartum. RESULTS: At 6 weeks postpartum median s-ferritin was 28 and 34 microg/L in Groups I and II, respectively, and a significantly higher mean s-ferritin (46.5 vs. 37.3 microg/L; p < 0.05) was found in women taking the highest dose. There were no correlations between s-ferritin in early pregnancy and at 6 weeks postpartum. Peripartum blood loss was the main indicator for iron status at 6 weeks postpartum. CONCLUSION: Iron supplementation based on iron status early in pregnancy, with 60 mg ferrous iron or 27 mg iron containing heme, resulted in adequate iron stores at 6 weeks postpartum among 75% or 70% of the women, respectively. However, 6 weeks were not sufficient to rebuild iron stores in women with large peripartum blood loss.