Changes in Lipid Composition Induced by Environmental and Genetic Manipulation in Synechocystis sp. PCC 6803

The objective of this research was to investigate the photosynthetic lipids synthesized by the cyanobacterium Synechocystis sp. PCC 6803 and to develop methods to extract, separate and characterize them. A particular focus has been directed towards the function of isoprenoid quinones and specifically the biosynthesis of plastoquinone, an essential component in photosynthetic and respiratory electron transport chains of cyanobacteria. This pathway differs from that in plants and algae and candidate genes assumed to be involved in this unresolved pathway were identified through in silico analyses. The gene deletion strain Δsll1653 was constructed and characterized to assess whether sll1653 is involved in plastoquinone synthesis or if a shift in the utilization of quinones can be initiated upon depletion of oxygen. The mutant strain had similar growth characteristics to the wild-type but failed to grow on glucose under high light. Spectroscopic and mass spectrometry analyses revealed accumulation of phycobilins and photoprotective carotenoids and tocopherols in the mutant strain. This strain was impaired in phylloquinone synthesis but a significant decrease in plastoquinone levels could not be observed. When the wild-type and mutant strain were subjected to limiting oxygen concentrations, both a state transition from PS II to PS I and an increase in F0 could be observed. Still, anaerobic conditions did not induce the replacement of plastoquinone by phylloquinone in the PQ-pool. The results obtained in this study indicate that the sll1653 gene, encoding a methyltransferase, is not directly involved in the biosynthesis of plastoquinone in Synechocystis sp. PCC 6803

Antimicrobial resistance—Do we share more than companionship with our dogs?

Aims To investigate and compare antimicrobial resistance genes (ARGs) in faeces from cohabiting dogs and owners. Methods and Results DNA from faecal samples from 35 dogs and 35 owners was screened for the presence of 34 clinically relevant ARGs using high throughput qPCR. In total, 24 and 25 different ARGs were present in the dog and owner groups, respectively. The households had a mean of 9.9 ARGs present, with dogs and owners sharing on average 3.3 ARGs. ARGs were shared significantly more in households with dogs over 6 years old (3.5, interquartile range 2.75–5.0) than in households with younger dogs (2.5, interquartile range 2.0–3.0) (p = 0.02). Dogs possessed significantly more mecA and aminoglycoside resistance genes than owners. Conclusions Dogs and owners can act as reservoirs for a broad range of ARGs belonging to several antimicrobial resistance classes. A modest proportion of the same resistance genes were present in both dogs and owners simultaneously, indicating that ARG transmission between the dog and human gut is of minor concern in the absence of antimicrobial selection. Significance and Impact of the Study This study provides insight into the common dog and human gut resistomes, contributing to an improved knowledge base in risk assessments regarding ARG transmission between dogs and humans.Antimicrobial resistance—Do we share more than companionship with our dogs?publishedVersio

Antithrombotic treatment after intracerebral hemorrhage: Surveys among stroke physicians in Scandinavia and the United Kingdom

BACKGROUND AND AIMS: It is unclear whether patients with previous intracerebral hemorrhage (ICH) should receive antithrombotic treatment to prevent ischemic events. We assessed stroke physicians' opinions about this, and their views on randomizing patients in trials assessing this question. METHODS: We conducted three web‐based surveys among stroke physicians in Scandinavia and the United Kingdom. RESULTS: Eighty‐nine of 205 stroke physicians (43%) responded to the Scandinavian survey, 161 of 180 (89%) to the UK antiplatelet survey, and 153 of 289 (53%) to the UK anticoagulant survey. In Scandinavia, 19 (21%) stroke physicians were uncertain about antiplatelet treatment after ICH for ischemic stroke or transient ischemic attack (TIA) and 21 (24%) for prior myocardial infarction. In the United Kingdom, 116 (77%) were uncertain for ischemic stroke or TIA and 115 (717%) for ischemic heart disease. In Scandinavia, 32 (36%) were uncertain about anticoagulant treatment after ICH for atrial fibrillation, and 26 (29%) for recurrent deep vein thrombosis or pulmonary embolism. In the United Kingdom, 145 (95%) were uncertain about anticoagulants after ICH in at least some cases. In both regions combined, 191 of 250 (76%) would consider randomizing ICH survivors in a trial of starting versus avoiding antiplatelets, and 176 of 242 (73%) in a trial of starting versus avoiding anticoagulants. CONCLUSION: Considerable proportions of stroke physicians in Scandinavia and the United Kingdom were uncertain about antithrombotic treatment after ICH. A clear majority would consider randomizing patients in trials assessing this question. These findings support the need for such trials

STudy of Antithrombotic Treatment after IntraCerebral Haemorrhage (STATICH): Protocol for a randomised controlled trial

Background and aims: Many patients with prior intracerebral haemorrhage have indications for antithrombotic treatment with antiplatelet or anticoagulant drugs for prevention of ischaemic events, but it is uncertain whether such treatment is beneficial after intracerebral haemorrhage. STudy of Antithrombotic Treatment after IntraCerebral Haemorrhage will assess (i) the effects of long-term antithrombotic treatment on the risk of recurrent intracerebral haemorrhage and occlusive vascular events after intracerebral haemorrhage and (ii) whether imaging findings, like cerebral microbleeds, modify these effects. Methods: STudy of Antithrombotic Treatment after IntraCerebral Haemorrhage is a multicentre, randomised controlled, open trial of starting versus avoiding antithrombotic treatment after non-traumatic intracerebral haemorrhage, in patients with an indication for antithrombotic treatment. Participants with vascular disease as an indication for antiplatelet treatment are randomly allocated to antiplatelet treatment or no antithrombotic treatment. Participants with atrial fibrillation as an indication for anticoagulant treatment are randomly allocated to anticoagulant treatment or no anticoagulant treatment. Cerebral CT or MRI is performed before randomisation. Duration of follow-up is at least two years. The primary outcome is recurrent intracerebral haemorrhage. Secondary outcomes include occlusive vascular events and death. Assessment of clinical outcomes is performed blinded to treatment allocation. Target recruitment is 500 participants. Trial status: Recruitment to STudy of Antithrombotic Treatment after IntraCerebral Haemorrhage is on-going. On 30 April 2020, 44 participants had been enrolled in 31 participating hospitals. An individual patient-data meta-analysis is planned with similar randomised trials

Changes in Lipid Composition Induced by Environmental and Genetic Manipulation in Synechocystis sp. PCC 6803

The objective of this research was to investigate the photosynthetic lipids synthesized by the cyanobacterium Synechocystis sp. PCC 6803 and to develop methods to extract, separate and characterize them. A particular focus has been directed towards the function of isoprenoid quinones and specifically the biosynthesis of plastoquinone, an essential component in photosynthetic and respiratory electron transport chains of cyanobacteria. This pathway differs from that in plants and algae and candidate genes assumed to be involved in this unresolved pathway were identified through in silico analyses. The gene deletion strain Δsll1653 was constructed and characterized to assess whether sll1653 is involved in plastoquinone synthesis or if a shift in the utilization of quinones can be initiated upon depletion of oxygen. The mutant strain had similar growth characteristics to the wild-type but failed to grow on glucose under high light. Spectroscopic and mass spectrometry analyses revealed accumulation of phycobilins and photoprotective carotenoids and tocopherols in the mutant strain. This strain was impaired in phylloquinone synthesis but a significant decrease in plastoquinone levels could not be observed. When the wild-type and mutant strain were subjected to limiting oxygen concentrations, both a state transition from PS II to PS I and an increase in F0 could be observed. Still, anaerobic conditions did not induce the replacement of plastoquinone by phylloquinone in the PQ-pool. The results obtained in this study indicate that the sll1653 gene, encoding a methyltransferase, is not directly involved in the biosynthesis of plastoquinone in Synechocystis sp. PCC 6803

Lærergrupper, systemteori og relasjonskompetanse

Tema for denne masteroppgaven er læreres arbeid med LP-modellen (LP står for læringsmiljø og pedagogisk analyse) og om dette arbeidet er med på å utvikle deres relasjonskompetanse. Sentralt i LP-modellen settes fokus på lærer-elev relasjonen og elev-elev relasjonen som betydningsfulle faktorer for elevtrivsel og læringsmiljø. Ved bruk av en analysemodell skal lærerne vurdere disse faktorene samt andre, som mulige opprettholdende faktorer for uønsket elevatferd og læringsproblemer. Jeg har formulert følgende problemstilling: Kan lærergruppers systematiske bruk av en systemteoretisk analysemodell med fokus på elevers læringsmiljø, bidra til utvikling av lærernes relasjonskompetanse? Formålet med oppgaven er å finne ut om lærerne har fått ny kunnskap om relasjoners betydning for læringsmiljøet, om arbeidet i lærergruppene har gitt større grad av refleksjon over egen klasseledelse i et relasjonelt perspektiv, og om dette gjenspeiler seg i utviklingen av strategier og tiltak. Forskningen tar utgangspunkt i to skoler på slutten av deres andre år med implementering av modellen. I oppgaven presenteres systemteorien som ligger bak LP-modellen samt hvordan lærerne arbeider med modellen i lærergruppene. Sentralt i oppgaven er begrepet relasjonskompetanse. Relasjonskompetanse defineres i oppgaven ved åtte dimensjoner. Jeg har valgt ulike metoder som intervju og dokument for innhenting av data. Med dette ønsker jeg å øke dataenes kvalitet. Analysen av materialet tematieres og deles inn i en beskrivende og en fortolkende fase for hvert tema. Den beskrivende fasen gir en første orden og oversikt over materialet. Data fra intervju og dokument fortolkes deretter opp mot sentrale funn som samlet trer fram i datagrunnlaget og ut fra teorien i oppgaven. Jeg fant i undersøkelsen min at lærerne ved deltagelse i LP gjennom to år sier at de har fått ny kunnskap om relasjoners betydning for læringsmiljøet, og de er villige til å reflektere over egen ledelse i klassen. De sier også at det er vanskelig å sette fokus på seg selv. Lærerne viser i intervju og gjennom dokumenter at de har fokus på relasjonelle forhold i skolen. De sier at de er inne i en prosess og at ting tar tid. Utvalget i oppgaven er så pass lite at jeg ikke generaliserer, men viser til tendenser i materialet som sier at arbeidet med analysemodellen i lærergruppene har bidratt til utvikling av lærernes relasjonskompetanse

Family groups of brown bears in Sør-Varanger, Norway Application of SNP and STR markers to reconstruct pedigrees from DNA-samples noninvasively collected 2004-2016

We reconstructed family relationships, parent-child and siblings, among the brown bear (Ursus arctos) sampled in Sør-Varanger, Norway. Basis of this study are observed family relationships by the wildlife management. We compared this strong indication of relatedness with testing particular family relationships using SNP- and STR-genotype data of 154 brown bears sampled mainly non-invasively in the area from 2004 to 2016. We calculated likelihood ratios (LRs) and reconstructed family groups with the program FAMILIAS, which was used to reconstruct family relationships in human forensics. When the LR of each relationship, parent-child or siblings, was tested, 40 (38.1%) relationships were confirmed based solely on genetic data. The allele sharing analysis visualized as dendrograms supported that a large proportion of the remaining observed cases that were not confirmed as parent-child or siblings did share a closer family relationship. More detailed analysis is necessary to deduce the nature of these relationships (cousins, uncle-nephew etc.). Based on the genetic data we found, that the minimum number of cubs per year was on average 4.08. The applied SNP-chip has been developed on the Swedish brown bear population, a population different to the bears living in Sør-Varanger. The performance of the SNP-chip in this study rises questions of its applicability for family analysis in other brown bear populations and shows the need for further evaluation of the individual loci on the chip. Nevertheless, the combined SNP-data from all loci seems to provide power enough to detect the previously reported subpopulation structure. The observational data, sampling effort and quality of the sample material of the brown bears in Sør-Varanger is remarkable and the material provides an excellent testing ground to validate and improve the SNP-chip to reconstruct family groups.publishedVersio

Hvor kommer Svanemuslingen i Transjøen fra?

En genetisk undersøkelse av svanemuslingen i Transjøen har avdekket tre unike genvarianter/haplotyper for Norge på cytochrome oxidase I genet som er en del av det mitokondrielle DNAet. En av disse variantene danner en egen gren i det evolusjonære treet ut fra den mest vanlige varianten i Europa. Det kan indikere at populasjonen i Norge har unike egenskaper som bør undersøkes videre.publishedVersio

Fluorometer setup.

<p>Photographs of the custom setup on a standard utility clamp stand. The dewar (a) holds the liquid nitrogen, and the samples. The 3D-printed housing (b) provides fittings for the excitation LED (c), the long-pass filter (d) and optical fiber (e).</p