71 research outputs found

    [Corrigendum to] Effects of small-scale turbulence on lower trophic levels under different nutrient conditions [vol 32, pg 197, 2010]

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    Small-scale turbulence affects the pelagic food web and energy flow in marine systems and the impact is related to nutrient conditions and the assemblage of organisms present. We generated five levels of turbulence (2*10 29 to 1*10 24 W kg 21 ) in land-based mesocosms (volume 2.6 m 3 ) with and without additional nutrients (31:16:1 Si:N:P m M) to asses the effect of small-scale turbulence on the lower part of the pelagic food web under different nutrient conditions. The ecological influence of nutrients and small-scale turbulence on lower trophic levels was quantified using multivariate statistics (RDA), where nutrients accounted for 31.8% of the observed biological variation, while 7.2% of the variation was explained by small-scale turbulence and its interaction with nutrients. Chlorophyll a, primary production rates, bacterial production rates and diatom and dinoflagellate abundance were positively correlated to turbulence, regardless of nutrient conditions. Abundance of autotrophic flagellates, total phytoplankton and bacteria were positively correlated to turbulence only when nutrients were added. Impact of small-scale turbulence was related to nutrient con- ditions, with implications for oligotrophic and eutrophic situations. The effect on community level was also different compared to single species level. Microbial processes drive biogeochemical cycles, and nutrient-controlled effects of small-scale turbulence on such processes are relevant to foresee altered carbon flow in marine systems

    Students in interprofessional clinical placements: How supervision facilitates patient-centeredness in collaborative learning

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    The patient’s role in interprofessional education is fundamental; however, it has received insufficient attention. This study explores how supervision facilitates and supports undergraduate students’ learning of patient-centeredness in interprofessional clinical placements. Data were generated in three clinical contexts based on a focused ethnography approach. We found that supervisors are engaged in student teams’ interprofessional learning, but often in their preparations or debriefings and seldom during patient encounters. The patient perspective is also less frequently scrutinized in planned interprofessional supervision sessions. Nevertheless, clinical settings provide numerous opportunities that may be exploited further

    Experimental poisoning by Baccharis megapotamica var. weirii in buffalo

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    Five male 6-8 month-old Murrah buffalo calves were orally dosed with the fresh aerial parts of Baccharis megapotamica var. weirii at doses of 1, 3, 4, 5 and 10g/kg body weight (bw) (~1-10mg macrocyclic trichothecenes/kg/bw). The B. megapotamica used for the experiment was harvested on a farm where a recent spontaneous outbreak of poisoning caused by such plant had occurred. Clinical signs appeared 4-20 hours and 4 buffaloes died 18-49 hours after the ingestion of the plant. Clinical signs were apathy, anorexia, and watery diarrhea, fever, colic, drooling, muscle tremors, restlessness, laborious breathing and ruminal atony, and dehydration. The most consistent gross findings were restricted to the gastrointestinal (GI) tract consisted of varying degrees of edema and reddening of the mucosa of the forestomach. Histopathological findings consisted of varying degrees of necrosis of the epithelial lining of the forestomach and of lymphocytes within lymphoid organs and aggregates. Fibrin thrombi were consistently found in sub-mucosal vessels of the forestomach and in the lumen of hepatic sinusoids. It is suggested that dehydration, septicemia and disseminated intravascular coagulation participate in the pathogenesis of the intoxication and play a role as a cause of death. A subsample of B. megapotamica var. weirii was frozen-dried and ground and analyzed using UHPLC (Ultra High Performance Liquid Chromatography) with high resolution Time of Flight mass spectrometry and tandem mass spectrometry, it was shown that the plant material contained at least 51 different macrocyclic trichothecenes at a total level of 1.1-1.2mg/g. About 15-20% of the total trichothecenes contents was found to be monosaccharide conjugates, with two thirds of these being glucose conjugates and one third constituted by six aldopentose conjugates (probably xylose), which has never been reported in the literature

    Aggressive dereplication using UHPLC–DAD–QTOF: screening extracts for up to 3000 fungal secondary metabolites

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    In natural-product drug discovery, finding new compounds is the main task, and thus fast dereplication of known compounds is essential. This is usually performed by manual liquid chromatography-ultraviolet (LC-UV) or visible light-mass spectroscopy (Vis-MS) interpretation of detected peaks, often assisted by automated identification of previously identified compounds. We used a 15 min high-performance liquid chromatography–diode array detection (UHPLC–DAD)–high-resolution MS method (electrospray ionization (ESI)(+) or ESI(−)), followed by 10–60 s of automated data analysis for up to 3000 relevant elemental compositions. By overlaying automatically generated extracted-ion chromatograms from detected compounds on the base peak chromatogram, all major potentially novel peaks could be visualized. Peaks corresponding to compounds available as reference standards, previously identified compounds, and major contaminants from solvents, media, filters etc. were labeled to differentiate these from compounds only identified by elemental composition. This enabled fast manual evaluation of both known peaks and potential novel-compound peaks, by manual verification of: the adduct pattern, UV–Vis, retention time compared with log D, co-identified biosynthetic related compounds, and elution order. System performance, including adduct patterns, in-source fragmentation, and ion-cooler bias, was investigated on reference standards, and the overall method was used on extracts of Aspergillus carbonarius and Penicillium melanoconidium, revealing new nitrogen-containing biomarkers for both species. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00216-013-7582-x) contains supplementary material, which is available to authorized users

    Front line defenders of the ecological niche! Screening the structural diversity of peptaibiotics from saprotrophic and fungicolous <i>Trichoderma/Hypocrea</i> species

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    Approximately 950 individual sequences of nonribosomally biosynthesised peptides are produced by the genus Trichoderma/Hypocreathat belong to a perpetually growing class of mostly linear antibiotic oligopeptides, which are rich in the non-proteinogenic α-aminoisobutyric acid (Aib). Thus, they are comprehensively named peptaibiotics. Notably, peptaibiotics represent ca. 80%of the total inventory of secondary metabolites currently known from Trichoderma/Hypocrea. Their unique membrane-modifying bioactivity results from amphipathicity and helicity, thus making them ideal candidates in assisting both colonisation and defence of the natural habitats by their fungal producers. Despite this, reports on the in vivo-detection of peptaibiotics have scarcely been published in the past. In order to evaluate the significance of peptaibiotic production for a broader range of potential producers, we screened nine specimensbelonging to seven hitherto uninvestigated fungicolous orsaprotrophic Trichoderma/Hypocrea species by liquid chromatographycoupled to electrospray high resolution mass spectrometry.Sequences of peptaibiotics found were independently confirmedby analysing the peptaibiome of pure agar culture

    Variants in the fetal genome near FLT1 are associated with risk of preeclampsia.

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    Preeclampsia, which affects approximately 5% of pregnancies, is a leading cause of maternal and perinatal death. The causes of preeclampsia remain unclear, but there is evidence for inherited susceptibility. Genome-wide association studies (GWAS) have not identified maternal sequence variants of genome-wide significance that replicate in independent data sets. We report the first GWAS of offspring from preeclamptic pregnancies and discovery of the first genome-wide significant susceptibility locus (rs4769613; P = 5.4 × 10-11) in 4,380 cases and 310,238 controls. This locus is near the FLT1 gene encoding Fms-like tyrosine kinase 1, providing biological support, as a placental isoform of this protein (sFlt-1) is implicated in the pathology of preeclampsia. The association was strongest in offspring from pregnancies in which preeclampsia developed during late gestation and offspring birth weights exceeded the tenth centile. An additional nearby variant, rs12050029, associated with preeclampsia independently of rs4769613. The newly discovered locus may enhance understanding of the pathophysiology of preeclampsia and its subtypes

    Countrywide outbreak of Pseudomonas aeruginosa in hospitals caused by premoistened non-sterile washcloths, Norway, 2021-2022

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    Source at https://www.fhi.no/I november 2021 ble Folkehelseinstituttet varslet om at tre intensivpasienter hadde dødd av blodbaneinfeksjon med bakterien Pseudomonas aeruginosa ved Universitetssykehuset Nord-Norge i Tromsø i løpet av kort tid. De hadde identiske isolater forenlig med et klonalt utbrudd. Helgenomsekvensering viste at det var en ny sekvenstype, ST3875, som ikke har vært påvist i Norge eller andre land. Nye tilfeller uten epidemiologiske sammenhenger, ble etter hvert funnet i flere andre sykehus, noe som indikerte en felles smittekilde. Den 17. januar 2022 var det påvist utbruddstilfeller i tre av fire helseregioner, og det ble 19. januar erkjent som et nasjonalt utbrudd. FHI overtok da koordinering av utbruddsarbeidet, og 20. januar ble det etablert en Sentral utbruddsgruppe med fagpersoner fra alle helseregionene. Den 21. januar var det 23 tilfeller i 9 sykehus i 3 regioner. Kasusdefinisjonen var en person med laboratoriebekreftet P. aeruginosa ST3875 fra oktober 2021 i sykehus i Norge, uavhengig av avdeling. Etter systematiske laboratorieundersøkelser av over 300 produkter påviste Oslo Universitetssykehus 18. mars 2022 utbruddsbakterien i pre-fuktede engangs vaskekluter av merket Oasis BedBath Unperfumed produsert i Lancashire, England. Sykehusene sluttet umiddelbart å bruke produktene. Vaskeklutene er definert som et kosmetisk produkt, og Mattilsynet er tilsynsmyndighet. Mattilsynet avdekket at produsenten og importøren ikke hadde full oversikt over produksjonslinjene og hvilke produkter som var forurenset. Det ble også avdekket at P. aeruginosa var blitt påvist i produkter under den interne kvalitetskontrollen i september 2021, uten at produktene var blitt stanset. Den 14. april tilbakekalte den engelske produsenten Vernacare produktene fra markedet både i Norge og internasjonalt. Per 14. juni 2022 omfattet utbruddet 388 tilfeller i 40 sykehus. Gjennomsnittsalder var 68 år og median alder 70 år (interkvartilområde 59- 79 år). Flertallet (63 %) av tilfellene var menn, og seks sykehus rapporterte Pseudomonas som sterkt medvirkende årsak til død hos totalt 8 tilfeller. Til sammen hadde 15 % av tilfellene ST3875 i blodkultur, 21 % i luftveier, 38 % i urin, 19 % i sår og 7 % i andre prøvematerialer, noe som tydet på flere mulige inngangsporter for bakterien. Antall nye tilfeller falt raskt etter at kilden var identifisert, og bruk av produktet ble stoppet i sykehus
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