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  • 1.
    Agnas, Axel Jönses Bernard
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Non-Independent Mate Choice in Female Humans (Homo sapiens): Progression to the Field 2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    There is much evidence that mate-choice decisions made by humans are affected by social/contextual information. Women seem to rate men portrayed in a relationship as more desirable than the same men when portrayed as single. Laboratory studies have found evidence suggesting that human mate choice, as in other species, is dependent on the mate choice decisions made by same-sex rivals. Even though non-independent mate choice is an established and well-studied area of mate choice, very few field studies have been performed. This project aims to test whether women’s evaluation of potential mates desirability is dependent/non-independent of same-sex rivals giving the potential mates sexual interest. This is the first field study performed in a modern human’s natural habitat aiming to test for non- independent mate choice in humans.

    No desirability enhancement effect was found. The possibilities that earlier studies have found an effect that is only present in laboratory environments or have measured effects other than non-independent mate choice are discussed. I find differences in experimental design to be the most likely reason why the present study failed to detect the effect found in previous studies. This field study, the first of its sort, has generated important knowledge for future experimenters, where the most important conclusion is that major limitations in humans ability to register and remember there surrounding should be taken in consideration when designing any field study investigating human mate choice. 

  • 2.
    Ajawatanawong, Pravech
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Baldauf, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    An automatable method for high throughput analysis of evolutionary patterns in slightly complex indels and its application to the deep phylogeny of Metazoa2014Article in journal (Refereed)
    Abstract [en]

    Insertions/deletions (indels) in protein sequences are potential powerful evolutionary markers. However, these characters have rarely been explored systematically at deep phylogenetic levels. Previous analyses of simple (2-state) clade defining indels (CDIs) in universal eukaryotic proteins found none to support any major animal clade. We hypothesized that CDIs might still be found in the remaining population of indels, which we term complex indels. Here, we propose a method for analyzing the simplest class of complex indels the “slightly complex indels”, and use these to investigate deep branches in animal phylogeny. Complex indels with two states, called bi-state indels, show similar evolutionary patterns to singleton simple indels and confirms that insertion mutations are more common than deletions. Exploration of CDIs in 2- to 9-state complex indels shows strong support for all examined branches of fungi and Archaeplastida. Surprisingly, we also found CDIs supporting major branches in animals, particular in vertebrates. We then expanded the search to non-bilaterial animals (Porifera, Cnidaria and Ctenophora). The phylogenetic tree reconstructed by CDIs places the Ctenophore Mnemiopsis leidyi as the deepest branch of animals with 6 CDIs support. Trichoplax adhaerens is closely related to the Bilateria. Moreover, the indel phylogeny shows Nematostella vectensis and Hydra magnipapillata are paraphyletic group and position of Cnidarian branches seems to be problematic in the indel phylogeny because of homoplasy. This might be solved if we discover CDIs from animal specific proteins, which emerged after the universal orthologous proteins.Evolutionary Patterns in Slightly Complex Protein Insertions/Deletions (Indels) and Their Application to the Study of Deep Phylogeny in Metazoa

  • 3. Ali, Imran
    et al.
    Penttinen-Damdimopoulou, Pauliina E
    Mäkelä, Sari I
    Berglund, Marika
    Stenius, Ulla
    Akesson, Agneta
    Håkansson, Helen
    Halldin, Krister
    Institutet för miljömedicin, Karolinska Institutet.
    Estrogen-like effects of cadmium in vivo do not appear to be mediated via the classical estrogen receptor transcriptional pathway.2010In: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 118, no 10, 1389-94 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Cadmium (Cd), a ubiquitous food contaminant, has been proposed to be an endocrine disruptor by inducing estrogenic responses in vivo. Several in vitro studies suggested that these effects are mediated via estrogen receptors (ERs).

    OBJECTIVE: We performed this study to clarify whether Cd-induced effects in vivo are mediated via classical ER signaling through estrogen responsive element (ERE)-regulated genes or if other signaling pathways are involved.

    METHODS: We investigated the estrogenic effects of cadmium chloride (CdCl2) exposure in vivo by applying the Organisation for Economic Co-operation and Development (OECD) rodent uterotrophic bioassay to transgenic ERE-luciferase reporter mice. Immature female mice were injected subcutaneously with CdCl2 (5, 50, or 500 µg/kg body weight) or with 17α-ethinylestradiol (EE2) on 3 consecutive days. We examined uterine weight and histology, vaginal opening, body and organ weights, Cd tissue retention, activation of mitogen-activated protein kinase (MAPK) pathways, and ERE-dependent luciferase expression.

    RESULTS: CdCl2 increased the height of the uterine luminal epithelium in a dose-dependent manner without increasing the uterine wet weight, altering the timing of vaginal opening, or affecting the luciferase activity in reproductive or nonreproductive organs. However, we observed changes in the phosphorylation of mouse double minute 2 oncoprotein (Mdm2) and extracellular signal-regulated kinase (Erk1/2) in the liver after CdCl2 exposure. As we expected, EE2 advanced vaginal opening and increased uterine epithelial height, uterine wet weight, and luciferase activity in various tissues.

    CONCLUSION: Our data suggest that Cd exposure induces a limited spectrum of estrogenic responses in vivo and that, in certain targets, effects of Cd might not be mediated via classical ER signaling through ERE-regulated genes.

  • 4. Ali, N.
    et al.
    Junaid, M.
    Ahmad, D.
    urRahman, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Katzenmeier, G.
    Antibacterial and antifungal activity of solvent extracts from Plumeria obtusa Linn2014In: Tropical Biomedicine, ISSN 0127-5720, Vol. 31, no 4, 607-615 p.Article in journal (Refereed)
    Abstract [en]

    Extracts of Plumeria obtusa are widely used in ethnomedicine and have been investigated for a variety of biological activities; however, the antimicrobial activity of P. obtusa flowers is poorly characterized. In this study, the antimicrobial activities of different solvents (petroleum ether, ethyl acetate, chloroform, isobutanol and ethanol) extracts from flowers of P. obtusa were investigated by a disc diffusion method against Gram-positive bacteria, Gram-negative bacteria and a fungus. All extracts exhibited growth inhibition of all microorganisms at variable degrees as measured by relative zones of inhibition, however, the petroleum ether extract was ineffective against Klebsiella pneumonia and ethyl acetate and isobutanol extracts were ineffective against Pseudomonas aeruginosa. The most susceptible Gram-positive bacterium was Bacillus subtilis while the most resistant Gram-positive bacterium was Staphylococcus aureus. Erwinia carotovora was the most susceptible Gram-negative bacterium while P. aeruginosa was highly resistant among the Gram-negative bacteria. In this study, for the first time, we investigated the antimicrobial activity of several different solvent extracts from flowers of P. obtusa against a broad spectrum of human-pathogenic microorganisms. These compounds warrant further investigation by isolation and structural elucidation with the aim to find novel and affordable bioactive compounds for the treatment of infectious diseases.

  • 5.
    Amalia, Clausson
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Hormonet leptin och dess funktioner2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 6. Babateen, Omar
    et al.
    Korol, Sergiy V.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology. Uppsala University.
    Jin, Zhe
    Bhandage, Amol K.
    Ahemaiti, Aikeremu
    Birnir, Bryndis
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology. Uppsala University.
    Liraglutide modulates GABAergic signaling in rat hippocampal CA3 pyramidal neurons predominantly by presynaptic mechanism2017In: BMC Pharmacology & Toxicology, E-ISSN 2050-6511, Vol. 18, no 83, 1-7 p.Article in journal (Refereed)
    Abstract [en]

    Background

    γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the brain where it regulates activity of neuronal networks. The receptor for glucagon-like peptide-1 (GLP-1) is expressed in the hippocampus, which is the center for memory and learning. In this study we examined effects of liraglutide, a GLP-1 analog, on GABA signaling in CA3 hippocampal pyramidal neurons.

    Methods

    We used patch-clamp electrophysiology to record synaptic and tonic GABA-activated currents in CA3 pyramidal neurons in rat hippocampal brain slices.

    Results

    We examined the effects of liraglutide on the neurons at concentrations ranging from one nM to one μM. Significant changes of the spontaneous inhibitory postsynaptic currents (sIPSCs) were only recorded with 100 nM liraglutide and then in just ≈50% of the neurons tested at this concentration. In neurons affected by liraglutide both the sIPSC frequency and the most probable amplitudes increased. When the action potential firing was inhibited by tetrodotoxin (TTX) the frequency and amplitude of IPSCs in TTX and in TTX plus 100 nM liraglutide were similar.

    Conclusions

    The results demonstrate that liraglutide regulation of GABA signaling of CA3 pyramidal neurons is predominantly presynaptic and more limited than has been observed for GLP-1 and exendin-4 in hippocampal neurons.

  • 7.
    Balck, Marianne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Phthalates in preschool dust: the relation between phthalates and parameters in the preschool environment2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Children are constantly exposed to many chemicals via the products they come in contactwith in their everyday life. One chemical group is phthalates, the most commonly usedplasticisers in the world. Phthalates are used mainly in PVC plastic products like floors, toys,food containers and wallpaper but they are also used in rubber, glue, paint, cables etc. Sincethese chemicals are weakly chemically bound to the PVC they can leak and migrate to the air,food, water and skin. Children are exposed to phthalates mainly through food, but because ofthe hand to mouth behaviour they are also exposed via dust inhalation and dust ingestion.About ten years ago regulations of the most toxic phthalates in toys and child care productswere implemented in the EU and from February 2015 it is a general prohibition for the use ofDEHP (diethylhexyl phthalate), DnBP (di-n-butyl phthalate), DiBP (diisobutyl phthalate) andBBzP (butyl benzyl phthalate). DiNP (diisononyl phthalate) is a relatively new phthalate andit has replaced DEHP to some extent in floors and toys. In phthalate free products DINCH(1,2-cyclohexane dicarboxylic acid diisononyl ester) is one of the plasticizer replacingphthalates. The banned phthalates have been shown to cause adverse effects on reproductionand recent research also investigates links between phthalate exposure and asthma and allergysymptoms in children. More experimental animal studies are needed to further investigate theasthma and allergy correlation.

    In the present project dust samples were collected from 30 preschool indoor environments inthe Stockholm city area to evaluate the levels of the six substances mentioned and thephthalate DEP (diethyl phthalate). The main aim of this thesis project was to search forrelations and links between the phthalate concentrations in dust and parameters from theindoor environment in preschools. Studied parameters are e.g. construction year, floor type,cleaning routines and quantity of toys and furniture made of plastic or foam. The project wascommissioned by the Swedish EPA and performed at the Institute of Environmental Medicine(IMM) at Karolinska Institutet.

    A negative relation was found between dust phthalate (DEHP and DnBP) concentrationand construction year. Also rooms with old PVC floors had higher concentrations of DEHPand DnBP in dust than rooms with new PVC floors. There was also a trend that dust frompreschools with PVC floors had higher DiNP concentration than dust from preschools withother floor types. The preschools that used foam mattresses for resting had higher DiNPconcentrations than those with no foam mattresses. Most preschools had new foammattresses, which could indicate a more common use of DiNP in new mattresses or mattress2covers compared to old mattresses that contains more DEHP. The four Waldorf preschoolsthat participated had lower DiNP dust concentrations than the other preschools, which wasexpected since Waldorf orientation includes using as little plastic material as possible. Norelation was found between the phthalate dust concentrations and the quantity of toys made ofsoft plastic in the sampled area.

    Many preschools had made a plastic inventory where they removed old and soft plastic toysand material. Also many preschools recently replaced old foam mattresses used for resting.This could be due to the big chemical focus in the media and authorities and the brochuresthat have been sent out the last couple of years about what preschool can do to decrease thechemical exposure of children. This interest and awareness seen in the preschools waspositive and hopefully the trend spreads to more preschools. Since children spend a big part oftheir time at preschools it is an important mission for society and the government to decreasethe exposure to hazardous chemicals there. Hopefully what has been done so far is just thebeginning.

  • 8.
    Balck, Marianne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Utgör användning av p-piller ett hot mot livskraftiga grodpopulationer?: Etinylöstradiols och levonorgestrels effekter hos arterna Xenopus leavis, Xenopus tropicalis och Rana temporaria2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En eskalerande minskning hos grodpopulationer och grodarter har skett världen över sedan 1980. Minskningen har påverkats av flera faktorer, bland annat utsläpp av endokrina ämnen till vattendrag. Endokrina ämnen är naturliga och syntetiska hormoner och kemikalier som stör människors och djurs hormonsystem. Syntetiska hormoner finns i p-piller och andra preventivmedel och hormonerna släpps ut i vattendrag via urinen. Det har visats att grodor påverkas av de syntetiska hormonerna etinylestradiol och levonorgestrel som finns i p-piller. Den här litteraturstudien syftar till att undersöka vilka effekter de två hormonerna har på modellarterna Xenopus laevis och Xenopus trolpicalis och på svenska grodarter såsom Rana temporaria. Effekterna är främst förändrad könskvot, med honor i majoritet, samt minskad fertilitet. Fertiliteten försämras genom missbildade könsorgan, genom att äggen mognar långsammare och honor kan bli sterila med avsaknad av äggledare. Hormonexponering kan leda till försenad metamorfos och det kan bli en högre mortalitet hos juvenila grodor. Även hormonuttryck kopplade till reproduktion och fertilitet kan påverkas av hormonexponering. Dock behövs mer forskning, särskilt i fält då mestadels experimentella studier gjorts hittills i laboratorier. Hormonutsläpp är en bidragande faktor till att sex av Sveriges åtta grodarter är rödlistade och i världen handlar det om tusentals arter. Även den så kallade cocktail effekten, det vill säga de effekter flera olika ämnen skapar tillsammans, bör undersökas närmare.

  • 9.
    Beijer, Kristina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Jönsson, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Shaik, Siraz
    Behrens, Daphné
    Brunström, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Brandt, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Azoles inhibit cytochrome P450 enzymes in rainbow trout involved in biotransformation and steroid hormone synthesis additively2015Manuscript (preprint) (Other academic)
  • 10.
    Beijer, kristina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Shaik, Siraz
    Berndt, Björlenius
    KTH.
    Lindberg, Richard
    Umeå Universitet.
    Brunström, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Brandt, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Reduction of pharmaceuticals and other contaminants in sewage treatment effluents by active carbon filtration and ozonation: Evaluation using biomarker responses in fish and chemical analysisManuscript (preprint) (Other academic)
  • 11. Berg, Andreas
    et al.
    Lindblad, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Svensson, Bo Håkan
    Cyanobacteria as a source of hydrogen for methane formation2014In: World Journal of Microbiology & Biotechnology, ISSN 0959-3993, E-ISSN 1573-0972, Vol. 30, no 2, 539-545 p.Article in journal (Refereed)
    Abstract [en]

    In a study during the 1970s co-variation of nitrogenase activity and methane formation associated with Sphagnum riparium was observed. This was suggested as evidence for a possible mechanism of hydrogen transfer from cyanobacteria to methanogens. We show experimentally that such a pathway is feasible. In a series of laboratory experiments, using a hydrogenase deficient strain of the heterocystous cyanobacterium Nostoc punctiforme and the hydrogenotrophic methanogen Methanospirillum hungateii in co-cultures, increasing light intensities resulted in elevated nitrogenase activity and methane production. The increase in methane production can be directly deduced from the nitrogenase activity of the N. punctiforme based on hydrogen balance calculations. These experimental results clearly suggest the possible existence of a novel photosynthetically regulated pathway for methane formation.

  • 12.
    Berg, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    An Amphibian Model for Studies of Developmental Reproductive Toxicity2012In: Developmental Toxicology: Methods and Protocols / [ed] Craig Harris, Jason M Hansen, Humana Press , 2012, 73-83 p.Chapter in book (Other academic)
  • 13.
    Berg, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Brunström, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Brandt, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Müllerian Duct Dysgenesis: a common cause for female reproductive disorders2012In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 211, no suppl., S184- p.Article in journal (Refereed)
  • 14.
    Berg, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Lundstedt-Enkel, KatrinUppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.Malmsten, JonasSLU.Persson, SaraSLU.
    Reproductive Disorders in Baltic Vertebrate Wildlife (BALTREP 2011): What is the status of, and the threats to reproductive health in Baltic region wildlife?2011Conference proceedings (editor) (Other academic)
  • 15.
    Berg, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Säfholm, Moa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Progestins: potent endocrine disrupters of the female reproductive system2012In: Abstract book: Part 2, 2012, 179-179 p.Conference paper (Refereed)
  • 16.
    Berg, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Säfholm, Moa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Fick, Jerker
    Umeå universitet.
    Norder, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Environmental progestin concentrations disrupt oogenesis in amphibians2012In: Abstract book: part 1, 2012Conference paper (Refereed)
  • 17.
    Berg, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Säfholm, Moa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Jansson, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Olsson, A. Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Fick, Jerker
    Umeå universitet.
    Brandt, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology.
    Combined Exposure to Progestin and Estrogen Mixtures: effects on vitellogenin and hormone receptor mRNA expression2012In: Comparative Biochemistry and Physiology A, ISSN 1095-6433, E-ISSN 1531-4332, Vol. 163, no suppl., S56-S57 p.Article in journal (Refereed)
  • 18.
    Bergsten, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Ecological Botany.
    Population Differentiation in Solidago virgaurea along Altitudinal Gradients2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Altitudinal gradients offer attractive opportunities for studies of population differentiation in response to environmental heterogeneity. In this thesis, I examined population differentiation along altitudinal gradients by combining common-garden experiments with field studies and experiments in alpine, subalpine and boreal populations of the perennial herb Solidago virgaurea. More specifically, I determined whether leaf physiology in terms of nitrogen concentration and resorption, flowering phenology, flower production and reproductive effort vary along altitudinal gradients.

    Nitrogen concentration in green leaves were higher in alpine than in subalpine and boreal populations. These differences persisted when plants were grown from seeds in a common-garden experiment at two sites, suggesting that the differences have a genetic component. There was mixed support for a trade-off between maximized carbon gain through the maintenance of high nitrogen concentration, and minimized nitrogen loss through high resorption.

    In their natural habitats alpine populations began flowering later than subalpine populations, but this difference was reversed when plants were grown in a common environment. This suggests that genetic differences among populations counteract environmental effects and reduce phenotypic variation in flowering time among populations. Flowering time thus shows countergradient genetic variation in S. virgaurea.

    In a common-garden experiment, boreal populations produced more flowers and had a higher reproductive effort than subalpine and alpine populations indicating habitat-specific genetic differences in reproductive allocation. In a field study, which included three populations, seed set was close to zero in the alpine population, intermediate in the subalpine population, and high in the boreal population. Experimental flower removal showed that seed production was associated with a considerable cost in terms of reduced flowering propensity the following year, but did not support the hypothesis that a large floral display is important for pollination success.

  • 19.
    Bergström, Ulrika
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology. ekotoxikologi.
    Olsson, Jan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology. ekotoxikologi.
    Hvidsten, Torgeir R
    Komorowski, Jan
    Brandt, Ingvar
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology. ekotoxikologi.
    Neurotoxicity of the Olfactory toxicant 2,6-Dichlorophenyl Methylsulphone in Olfactory bulb:Impaired expression of genes relating to neurodegenerative disease2007In: DIOXIN2007, 2007, 1841-1844 p.Conference paper (Refereed)
  • 20. Björn, Lars Olof
    et al.
    Bengtson, Sven-Axel
    Shaoshan, Li
    Hecker, Christoph
    Ullah, Saleem
    Roos, Arne
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nilsson, Annica M.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Thermal emissivity of avian eggshells2016In: Journal of Thermal Biology, ISSN 0306-4565, E-ISSN 1879-0992, Vol. 57, 1-5 p.Article in journal (Refereed)
    Abstract [en]

    The hypothesis has been tested that evolution has resulted in lower thermal emissivity of eggs of birds breeding openly in cold climates than of eggs of birds that nest under protective covering or in warmer climates. Directional thermal emissivity has been estimated from directional-hemispherical reflectance spectra. Due to several methodological difficulties the absolute emissivity is not accurately determined, but differences between species are obvious. Most notably, small waders of the genus Calidris, breeding in cold climates on the tundra, and in most cases with uniparental nest attendance, have low directional emissivity of their eggshells, about 0.92 when integration is carried out for wavelengths up to 16 mu m. Species belonging to Galloanserinae have the highest directional emissivity, about 0.96, of their eggs. No differences due to climate or breeding conditions were found within this group. Eggs of most other birds tested possess intermediate emissivity, but the values for Pica pica and Corvus corone cornix are as low as for Calidris. Large species-dependent differences in spectral reflectance were found at specific wavelengths. For instance, at 4.259 mu m the directional-hemispherical reflectance for galliforms range from 0.05 to 0.09, while for Fratercula arctica and Fulmarus glacialis it is about 0.3. The reflection peaks at 6.5 and 11.3 mu m due to calcite are differentially attenuated in different species. In conclusion, the hypothesis that evolution has resulted in lower thermal emissivity of bird eggs being exposed in cold climates is not supported by our results. The emissivity is not clearly related to nesting habits or climate, and it is unlikely that the small differences observed are ecologically important. The spectral differences between eggs that nevertheless exist should be taken into account when using infrared thermometers for estimating the surface temperature of avian eggs.

  • 21.
    Bohlin, Matilda
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    DEHP - från mjukgörare till hormonstörande2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 22. Bondesson, Maria
    et al.
    Jönsson, Jill
    Pongratz, Ingemar
    Olea, Nicholas
    Cravedi, Jean-Pierre
    Zalko, Daniel
    Håkansson, Helen
    Halldin, Krister
    Institutet för miljömedicin, Karolinska Institutet.
    Di Lorenzo, Diego
    Behl, Christian
    Manthey, Dieter
    Balaguer, Patrick
    Demeneix, Barbara
    Fini, Jean Baptiste
    Laudet, Vincent
    Gustafsson, Jan-Ake
    A CASCADE of effects of bisphenol A.2009In: Reproductive Toxicology, ISSN 0890-6238, E-ISSN 1873-1708, Vol. 28, no 4, 563-7 p.Article in journal (Refereed)
  • 23.
    Bottinelli, Arianna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Applied Mathematics and Statistics.
    van Wilgenburg, E.
    Fordham Univ, Dept Biol Sci, Bronx, NY 10458 USA..
    Sumpter, David J. T.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Applied Mathematics and Statistics.
    Latty, T.
    Univ Sydney, Sch Biol Sci, Sydney, NSW 2006, Australia..
    Local cost minimization in ant transport networks: from small-scale data to large-scale trade-offs2015In: Journal of the Royal Society Interface, ISSN 1742-5689, E-ISSN 1742-5662, Vol. 12, no 112, 20150780Article in journal (Refereed)
    Abstract [en]

    Transport networks distribute resources and information in many human and biological systems. Their construction requires optimization and balance of conflicting criteria such as robustness against disruptions, transport efficiency and building cost. The colonies of the polydomous Australian meat ant Iridomyrmex purpureus are a striking example of such a decentralized network, consisting of trails that connect spatially separated nests. Here we study the rules that underlie network construction in these ants. We find that a simple model of network growth, which we call the minimum linking model (MLM), is sufficient to explain the growth of real ant colonies. For larger networks, the MLM shows a qualitative similarity with a Euclidean minimum spanning tree, prioritizing cost and efficiency over robustness. We introduce a variant of our model to show that a balance between cost, efficiency and robustness can be also reproduced at larger scales than ant colonies. Remarkably, such a balance is influenced by a parameter reflecting the specific features of the modelled transport system. The extended MLM could thus be a suitable source of inspiration for the construction of cheap and efficient transport networks with non-zero robustness, suggesting possible applications in the design of human-made networks.

  • 24.
    Buratovic, Sonja
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Low-Dose Ionizing Radiation Induces Neurotoxicity in the Neonate: Acute or fractionated doses and interaction with xenobiotics in mice2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis examines the developmental neurotoxic effects of exposure to low-dose ionizing radiation (IR), alone or together with xenobiotics, during a critical period of neonatal brain development in mice.

    During mammalian brain development there is a period called the brain growth spurt (BGS), which involves extensive growth and maturation of the brain. It is known that neonatal exposure during the BGS to xenobiotics can have a negative impact on neonatal brain development, resulting in impaired cognitive function in the adult mouse. In humans, the BGS starts during the third trimester of pregnancy and continues for approximately 2 years in the child.  

    The present thesis has identified a defined critical period, during the BGS, when IR can induce developmental neurotoxicity in mice. The observed neurotoxicity was not dependent on sex or strain and manifested as altered neurobehaviour in the adult mouse. Furthermore, fractionated dose exposures appear to be as potent as a higher acute dose. The cholinergic system can be a target system for developmental neurotoxicity of IR, since alterations in adult mouse cholinergic system susceptibility were observed. Co-exposure to IR and nicotine exacerbated the behavioural disturbances and cholinergic system dysfunction. Furthermore, co-exposure with the environmental agent paraquat has indicated that the dopaminergic system can be a potential target.  

    In this thesis, clinically relevant doses of IR and a sedative/anesthetic agent (ketamine) were shown to interact and exacerbate defects in adult mouse neurobehaviour, learning and memory, following neonatal exposure, at doses where the single agents did not have any impact on the measured variables. This indicates a shift in the dose-response curve for IR, towards lower doses, if exposure occurs during the neonatal brain development. In addition, co-exposed mice, showing cognitive defects, expressed elevated levels of tau protein in the cerebral cortex. Furthermore, exacerbation of neurochemical deviations were observed following co-exposure compared to irradiation alone.

    Further investigations of neurotoxic effects following fractionated or acute low-dose IR, modelling the clinical situation during repeated CT scans or levels of radiation deposited in non-target tissue during radiotherapy, and possible interaction effects with xenobiotics, is of great importance in the field of radioprotection. 

    List of papers
    1. Neonatal exposure to whole body ionizing radiation induces adult neurobehavioural defects: Critical period, dose-response effects and strain and sex comparison
    Open this publication in new window or tab >>Neonatal exposure to whole body ionizing radiation induces adult neurobehavioural defects: Critical period, dose-response effects and strain and sex comparison
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    2016 (English)In: Behavioural Brain Research, ISSN 0166-4328, E-ISSN 1872-7549, Vol. 304, 11-19 p.Article in journal (Refereed) Published
    Abstract [en]

    Development of the brain includes periods which can be critical for its normal maturation. The present study investigates specifically vulnerable peri-/postnatal periods in mice which are essential for understanding the etiology behind radiation induced neurotoxicity and functional defects, including evaluation of neurotoxicity between sexes or commonly used laboratory mouse strains following low/moderate doses of ionizing radiation (IR). Male Naval Medical Research Institute (NMRI) mice, whole body irradiated to a single 500 mGy IR dose, on postnatal day (PND) 3 or PND 10 showed an altered adult spontaneous behaviour and impaired habituation capacity, whereas irradiation on PND 19 did not have any impact on the studied variables. Both NMRI and C57bl/6 male and female mice showed an altered adult spontaneous behaviour and impaired habituation following a single whole body irradiation of 500 or 1000 mGy, but not after 20 or 100 mGy, on PND 10. The present study shows that exposure to low/moderate doses of IR during critical life stages might be involved in the induction of neurological/neurodegenerative disorder/disease. A specifically vulnerable period for radiation induced neurotoxicity seems to be around PND 3-10 in mice. Further studies are needed to investigate mechanisms involved in induction of developmental neurotoxicity following low dose irradiation.

    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:uu:diva-282365 (URN)10.1016/j.bbr.2016.02.008 (DOI)000372939400002 ()26876140 (PubMedID)
    Funder
    Swedish Radiation Safety AuthorityEU, FP7, Seventh Framework Programme, 29552
    Available from: 2016-04-05 Created: 2016-04-05 Last updated: 2017-11-30Bibliographically approved
    2. Neonatal exposure to a moderate dose of ionizing radiation causes behavioural defects and altered levels of tau protein in mice
    Open this publication in new window or tab >>Neonatal exposure to a moderate dose of ionizing radiation causes behavioural defects and altered levels of tau protein in mice
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    2014 (English)In: Neurotoxicology, ISSN 0161-813X, E-ISSN 1872-9711, Vol. 45, 48-55 p.Article in journal (Refereed) Published
    Abstract [en]

    Medical use of ionizing radiation (IR) has great benefits for treatment and diagnostic imaging, butprocedures as computerized tomography (CT) may deliver a significant radiation dose to the patient.Recently, awareness has been raised about possible non-cancer consequences from low dose exposure toIR during critical phases of perinatal and/or neonatal brain development.In the present study neonatal NMRI mice were whole body irradiated with a single dose of gammaradiation (0; 350 and 500 mGy) on postnatal day 10 (PND 10). At 2 and 4 months of age, mice of bothsexes were observed for spontaneous behaviour in a novel home environment. The neuroproteinsCaMKII, GAP-43, synaptophysin and total tau in male mouse cerebral cortex and hippocampus wereanalysed 24 h post-irradiation and in adults at 6 months of age exposed to 0 or 500 mGy on PND 10.A significantly dose-response related deranged spontaneous behaviour in 2- and 4-month-old micewas observed, where both males and females displayed a modified habituation, indicating reducedcognitive function. The dose of 350 mGy seems to be a tentative threshold. Six-month-old male miceshowed a significantly increased level of total tau in cerebral cortex after irradiation to 500 mGy compared to controls. This demonstrates that a single moderate dose of IR, given during a defined criticalperiod of brain development, is sufficient to cause persistently reduced cognitive function. Moreover, anelevation of tau protein was observed in male mice displaying reduced cognitive function.

    National Category
    Other Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-240576 (URN)10.1016/j.neuro.2014.09.002 (DOI)000346955100006 ()25265567 (PubMedID)
    Available from: 2015-01-08 Created: 2015-01-08 Last updated: 2017-06-30Bibliographically approved
    3. Developmental effects of fractionated low-dose exposure to gamma radiation on behaviour and susceptibility of the cholinergic system in mice
    Open this publication in new window or tab >>Developmental effects of fractionated low-dose exposure to gamma radiation on behaviour and susceptibility of the cholinergic system in mice
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    2016 (English)In: International Journal of Radiation Biology, ISSN 0955-3002, E-ISSN 1362-3095, Vol. 92, no 7, 371-379 p.Article in journal (Refereed) Published
    Abstract [en]

    Purpose: To investigate whether neonatal exposure to fractionated external gamma radiation and co-exposure to radiation and nicotine can affect/exacerbate developmental neurotoxic effects, including altered behavior/cognitive function and the susceptibility of the cholinergic system in adult male mice. Materials and methods: Neonatal male Naval Medical Research Institute (NMRI) mice were irradiated with one 200 mGy fraction/day and/or exposed to nicotine (66 μg/kg b.w.) twice daily on postnatal day (PND) 10, 10–11, 10–12 or 10–13 (nicotine only). At 2 months of age the animals were tested for spontaneous behavior in a novel home environment, habituation capacity and nicotine-induced behavior. Results: Fractionated irradiation and co-exposure to radiation and nicotine on three consecutive days disrupted behavior and habituation and altered susceptibility of the cholinergic system. All observed effects were significantly more pronounced in mice co-exposed to both radiation and nicotine. Conclusions: The fractionated irradiation regime affects behavior/cognitive function in a similar manner as has previously been observed for single-dose exposures. Neonatal co-exposure to radiation and nicotine, during a critical period of brain development in general and cholinergic system development in particular, enhance these behavioral defects suggesting that the cholinergic system can be a target system for this type of developmental neurotoxic effects.

    Keyword
    Low-dose radiation, nicotine, cholinergic system, cognition, brain development, behavior
    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:uu:diva-282366 (URN)10.3109/09553002.2016.1164911 (DOI)000379933800003 ()27043364 (PubMedID)
    Available from: 2016-04-05 Created: 2016-04-05 Last updated: 2017-11-30Bibliographically approved
    4. Developmental effects of neonatal fractionated co-exposure to low-dose gamma radiation and paraquat on behaviour in adult mice
    Open this publication in new window or tab >>Developmental effects of neonatal fractionated co-exposure to low-dose gamma radiation and paraquat on behaviour in adult mice
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:uu:diva-282374 (URN)
    Available from: 2016-04-05 Created: 2016-04-05 Last updated: 2016-05-12
    5. Ketamine interacts with low dose ionizing radiaiton during brain development to impair cognitive function in mouse
    Open this publication in new window or tab >>Ketamine interacts with low dose ionizing radiaiton during brain development to impair cognitive function in mouse
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    2016 (English)In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175Article in journal (Refereed) Submitted
    National Category
    Developmental Biology
    Identifiers
    urn:nbn:se:uu:diva-282371 (URN)
    Available from: 2016-04-05 Created: 2016-04-05 Last updated: 2017-11-30Bibliographically approved
  • 25. Deneubourg, Jean-Louis
    et al.
    Nicolis, Stamatios C.
    Detrain, Claire
    Optimality of communication in self-organised social behaviour2005In: Self-Organisation and Evolution of Biological and Social Systems, Cambridge: Cambridge University Press, 2005, 25-35 p.Chapter in book (Other academic)
  • 26. Doak, Daniel F.
    et al.
    Boor, Gina K. Himes
    Bakker, Victoria J.
    Morris, William F.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Louthan, Allison
    Morrison, Scott A.
    Stanley, Amanda
    Crowder, Larry B.
    Recommendations for Improving Recovery Criteria under the US Endangered Species Act2015In: BioScience, ISSN 0006-3568, E-ISSN 1525-3244, Vol. 65, no 2, 189-199 p.Article in journal (Refereed)
    Abstract [en]

    Recovery criteria, the thresholds mandated by the Endangered Species Act that define when species may be considered for downlisting or removal from the endangered species list, are a key component of conservation planning in the United States. We recommend improvements in the definition and scientific justification of recovery criteria, addressing both data-rich and data-poor situations. We emphasize the distinction between recovery actions and recovery criteria and recommend the use of quantitative population analyses to measure the impacts of threats and to explicitly tie recovery criteria to population status. To this end, we provide a brief tutorial on the legal and practical requirements and constraints of recovery criteria development. We conclude by contrasting our recommendations with other alternatives and by describing ways in which academic scientists can contribute productively to the planning process and to endangered species recovery.

  • 27.
    Doshi, Jiten
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. ETH Zurich.
    A platform for Chinese hamster ovary (CHO) cell genome engineering2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The production of therapeutic recombinant proteins in heterologous systems has gained significance since the last decade. For recombinant proteins that require post-translational modifications (PTMs), mammalian systems are preferred. Chinese hamster ovary (CHO) cells are the mammalian cells of choice for production of recombinant proteins. This is because of their ability to provide correct protein-folding and post-translational modifications, displaying high productivity at large scale, ability to grow in suspension mode at high densities in a serum-free media, incapable of infection by most viruses and their history of regulatory approvals. There is an established state of the art technology for development of CHO cells for recombinant protein production. This technology relies on random integration of the gene of interest and gene amplification process for obtaining high expressing clones. There is a high degree of clonal heterogeneity and instability observed in the screened clones. To overcome the process of random integration, this report describes a lentivirus based screening for search of stable and high expressing integration sites in CHO cells. The integration sites are identified by using nrLAM-PCR (non-restrictive linear amplification mediated PCR) coupled with high throughput sequencing. Lentivirus are chosen as they preferentially integrate within the coding regions rendering the possibility of obtaining stable and high expressing clones. In addition, lentivirus vector is designed to possess landing pad for recombinase mediated cassette exchange of viral sequence with foreign DNA. The report describes a successful cassette exchange reaction but with low efficiency. Genome engineering technologies such as CRISPR/Cas, TALENs can used for targeted gene insertion at integration sites and thus establishing stable and efficient production of recombinant proteins in CHO cells. Additionally, an approach for designing synthetic promoters based on Ef1α promoter architecture has been shown. Synthetic promoters are useful for expression of multi-gene cassettes as they are short in length and provide comparable expression levels to the native mammalian promoter. 

  • 28.
    Durall de la Fuente, Claudia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Lindblad, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Mechanisms of carbon fixation and engineering for increased carbon fixation in cyanobacteria2015In: ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS, ISSN 2211-9264, Vol. 11, 263-270 p.Article, review/survey (Refereed)
    Abstract [en]

    Cyanobacteria, gram-negative prokaryotic microorganisms, perform oxygenic photosynthesis with a photosynthetic machinery similar to higher plants which includes ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) as the main CO2-fixing enzyme. Currently, there is a growing interest to use cyanobacteria as photosynthetic microbial cell factories for the direct production of solar fuels or other compounds of human interest. However, rates and efficiencies to produce e.g. biofuels are still very low. The amount of available fixed carbon for the synthesis of desired product(s) may be one of the limiting steps. This contribution reviews CO2-fixation in cyanobacteria with focus on CO2-concentrating mechanisms, RuBisCO, phosphoenolpyruvate carboxylase and other carboxylases, engineering approaches for increased carbon fixation, and finally the synthetic malonyl-CoA-oxaloacetate-glyoxylate pathways.

  • 29.
    Gao, Kai
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Basal and Pollutant-induced Expression of CYP1A, 1B and 1C isoforms in Fish: Implications for Biomonitoring2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aquatic wildlife are exposed to contaminants in their natural habitats, and toxic pollutants may induce toxicity in sensitive target tissues and cells. There is therefore a need to establish biomarkers to determine exposure to certain classes of contaminants and the subsequent biological responses. In the present work the whole suite of cytochrome P450 1 (CYP1) genes expressed in fish were examined with regard to their inducibility and potential use as biomarkers. Complementary DNA of the CYP1A, 1B and 1C transcripts in rainbow trout and three-spined stickleback were cloned and characterized by quantitative mRNA expression analysis. All CYP1 transcripts could be induced by two selected aryl hydrocarbon receptor (AhR) agoinsts (indigo and PCB 126) in both species, suggesting that all genes were regulated by the AhR. CYP1 mRNA expression profiles induced by PCB 126 and indigo varied over time showing that PCB 126 gave rise to a high and persistent induction in gills and liver while induction by indigo was transient in both organs. The uptake and kinetics of 14C-indigo was studied by autoradiography in rainbow trout. A rapid uptake of 14C-indigo from the water and a subsequent elimination in bile and intestinal contents was observed, explaining the transient CYP1 induction. A high accumulation of 14C-indigo in the gills was completely blocked the CYP1 inhibitor ellipticine, suggesting a CYP1-dependent uptake. High dilutions of a sewage treatment plant effluent containing a complex mixture of pharmaceuticals were investigated. The same water sample both induced CYP1A mRNA expression and inhibited catalytic activity of CYP1A. A field study revealed different induction signatures of the CYP1 genes examined at various locations in Uppsala water environments. As concluded by the temporal and spatial responses obtained, the results of this work suggest that the CYP1 gene panel could be used for biomonitoring of environmental contaminants acting on the CYP system. Further field studies will be required to evaluate this possibility.

    List of papers
    1. Induction patterns of new CYP1 genes in environmentally exposed rainbow trout
    Open this publication in new window or tab >>Induction patterns of new CYP1 genes in environmentally exposed rainbow trout
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    2010 (English)In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 98, no 4, 311-321 p.Article in journal (Refereed) Published
    Abstract [en]

    The cytochrome P4501 (CYP1) gene family comprises four subfamilies in fish: CYP1A, CYP1B, CYP1C, and CYP1D. Only two CYP1 genes, CYP1A1 and CYP1A3, are so far known in rainbow trout (Oncorhynchus mykiss). The present study aimed to identify other CYP1 subfamily genes in rainbow trout, to establish methods for quantitative mRNA expression analysis of these genes, and to determine their basal and induced mRNA expression in gills and liver. Another goal was to examine their mRNA expression in environmentally exposed fish. We cloned four new transcripts, denoted rbCYP1B1, rbCYP1C1, rbCYP1C2, and rbCYP1C3. Levels of these and the previously known rbCYP1A transcripts were determined by real-time PCR in unexposed fish, fish exposed to the potent aryl hydrocarbon receptor (AhR) agonist 3,3',4,4',5-pentachlorobiphenyl (PCB126), and fish caged in various waters in the Uppsala region (Sweden). The mRNA expression patterns observed in unexposed rainbow trout (basal levels) were markedly similar to those reported for orthologous genes in other species. All six transcripts were induced by PCB126 in gills and liver, suggesting all genes to be AhR regulated. The caged fish showed clear rbCYP1 induction in gills at all monitoring sites (up to 70-fold the basal level), whereas the liver responses were weak; induction (up to 5-fold) was recorded only at the Uppsala municipal sewage treatment plant outlet. Gill filament EROD activity was induced at all caging sites. Most interestingly, the rbCYP1 gene response patterns in gills differed among caging sites and among subfamilies. The EROD induction seemed to only reflect induction of rbCYP1A transcription. Response patterns of multiple CYP1 genes in gills and liver could provide an improved monitoring strategy. Such patterns could be used to characterize complex mixtures of AhR agonists and antagonists in aquatic environments.

    National Category
    Biological Sciences
    Research subject
    Ecotoxicology
    Identifiers
    urn:nbn:se:uu:diva-130469 (URN)10.1016/j.aquatox.2010.03.003 (DOI)000278982800001 ()20371123 (PubMedID)
    Available from: 2010-09-08 Created: 2010-09-08 Last updated: 2017-12-12Bibliographically approved
    2. Cytochrome P450 1A, 1B, and 1C mRNA induction patterns in three-spined stickleback exposed to a transient and a persistent inducer
    Open this publication in new window or tab >>Cytochrome P450 1A, 1B, and 1C mRNA induction patterns in three-spined stickleback exposed to a transient and a persistent inducer
    2011 (English)In: Comparative Biochemistry and Physiology - Part C: Toxicology & Pharmacology, ISSN 1532-0456, E-ISSN 1878-1659, Vol. 154, no 1, 42-55 p.Article in journal (Refereed) Published
    Abstract [en]

    Cytochrome P450 1 (CYP1) mRNA induction patterns in three-spined stickleback (Gasterosteus aculeatus) were explored for use in environmental monitoring of aryl hydrocarbon receptor (AHR) agonists. The cDNAs of stickleback CYP1A, CYP1B1, CYP1C1, and CYP1C2 were cloned and their basal and induced expression patterns were determined in the brain, gill, liver and kidney. Also, their induction time courses were compared after waterborne exposure to a transient (indigo) or a persistent (3,3',4,4',5-pentacholorbiphenyl PCB 126) AHR agonist. The cloned stickleback CYP1s exhibited a high amino acid sequence identity compared with their zebrafish orthologs and their constitutive tissue distribution patterns largely agreed with those reported in other species. PCB 126 (100 nM) induced different CYP1 expression patterns in the four tissues, suggesting tissue-specific regulation. Both indigo (1 nM) and PCB 126 (10 nM) induced a strong CYP1 expression in gills. However, while PCB 126 gave rise to a high and persistent induction in gills and liver, induction by indigo was transient in both organs. The number of putative dioxin response elements found in each CYP1 gene promoter roughly reflected the induction levels of the genes. The high responsiveness of CYP1A,CYP1B1, and CYP1C1 observed in several organs suggests that three-spined stickleback is suitable for monitoring of pollution with AHR agonists.

    Keyword
    Three-spined stickleback, Cytochrome P450 1A, Cytochrome P450 1B, Cytochrome P450 1C, CYP1A gene, CYP1B gene, CYP1C gene, Gill EROD activity, Indigo, PCB 126, Biomarkers
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-155388 (URN)10.1016/j.cbpc.2011.02.005 (DOI)000291178700007 ()
    Available from: 2011-06-22 Created: 2011-06-22 Last updated: 2017-12-11Bibliographically approved
    3. Effluent from drug manufacturing affects cytochrome P450 1 regulation and function in fish
    Open this publication in new window or tab >>Effluent from drug manufacturing affects cytochrome P450 1 regulation and function in fish
    Show others...
    2013 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 90, no 3, 1149-1157 p.Article in journal (Refereed) Published
    Abstract [en]

    We have previously reported very high concentrations of pharmaceuticals in the effluent from a treatment plant receiving wastewater from about 90 bulk drug manufacturers near Hyderabad, India. The main objective of the present study was to examine how high dilutions of this effluent affect mRNA expression of cytochrome P450 (CYP) 1 family genes and ethoxyresorufin O-deethylase (EROD) activity in exposed wildlife, using the three-spined stickleback (Gasterosteus aculeatus) as a model. In gill filaments exposed to diluted effluent ex vivo, EROD activity was strongly inhibited in a concentration-dependent manner. In a subsequent in vivo study, groups of fish were exposed (24. h) to three concentrations of effluent, 0.8%, 1.6% or 3.2%. In this experiment, EROD in gills was induced 27-, 52- or 60-fold, respectively. Accordingly, CYP1A mRNA was markedly up-regulated in gill, liver and brain of fish exposed to all three effluent concentrations. Expression of mRNA for CYP1B1 and CYP1C1 was induced in gills at all concentrations while effects on these genes in liver and brain were weak or absent. The results of a time course study suggested that most CYP1-inducing substances in the effluent were readily metabolised or excreted, because the induced EROD activity and mRNA expression decreased when the fish were transferred to clean water. Considering that CYP1 enzymes play important roles in biotransformation of endogenous and foreign compounds, the observed dual effect of the effluent on CYP1 catalytic activity and mRNA expression suggests that multiple physiological functions could be affected in exposed wildlife.

    Keyword
    CYP1, EROD, Gills, Pharmaceuticals, Three-spined stickleback, Treated wastewater, Drug products, Effluent treatment, Fish, Gene expression, Wastewater treatment, Effluents, cytochrome P450, cytochrome P450 1, cytochrome P450 1A, cytochrome P450 1B1, cytochrome P450 1C1, cytochrome P450 1C2, ethoxyresorufin deethylase, industrial effluent, messenger RNA, tap water, unclassified drug, biotransformation, concentration (composition), drug, ecological modeling, effluent, enzyme activity, manufacturing, metabolism, pollution exposure, teleost, wastewater, water treatment, animal experiment, animal tissue, article, brain, controlled study, enzyme induction, enzyme inhibition, female, Gasterosteus aculeatus, gene, genetic transcription, gill, liver, mortality, nonhuman, spiggin gene, upregulation, vitellogenin gene, waste water treatment plant, Andhra Pradesh, Hyderabad [Andhra Pradesh], India
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-192012 (URN)10.1016/j.chemosphere.2012.09.023 (DOI)000312978700035 ()
    Note

    De två första författarna delar förstaförfattarskapet.

    Available from: 2013-01-24 Created: 2013-01-15 Last updated: 2017-12-06Bibliographically approved
    4. Disposition of indigo in rainbow trout:  Relationships between tissue binding kinetics and CYP gene induction
    Open this publication in new window or tab >>Disposition of indigo in rainbow trout:  Relationships between tissue binding kinetics and CYP gene induction
    (English)Manuscript (preprint) (Other academic)
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-198644 (URN)
    Available from: 2013-04-22 Created: 2013-04-22 Last updated: 2013-04-29
  • 30. Halldin, Krister
    et al.
    Axelsson, Jeanette
    Avd för ekotoxikologi. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Brandt, Ingvar
    Avd för ekotoxikologi. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Brunström, Björn
    Avd för ekotoxikologi. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Developmental toxicity in Japanese quail exposed to hydroxylated metabolites pf PCBs in ovo.2005In: Avian and Poultry Biology Reviews, no 16, 11-17 p.Article in journal (Refereed)
  • 31. Halldin, Krister
    et al.
    Axelsson, Jeanette
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Brunström, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Effects of endocrine modulators on sexual differentiation and reproductive function in male Japanese quail.2005In: Brain Res Bull, ISSN 0361-9230, Vol. 65, no 3, 211-8 p.Article in journal (Refereed)
  • 32.
    Halldin, Krister
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Berg, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Bergman, Åke
    Brandt, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Brunström, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Environmental Toxicology.
    Distribution of bisphenol A and tetrabromobisphenol A in quail eggs, embryos and laying birds and studies on reproduction variables in adults following in ovo exposure2001In: ARCHIVES OF TOXICOLOGY, ISSN 0340-5761, Vol. 75, no 10, 597-603 p.Article in journal (Refereed)
    Abstract [en]

    In a previous study, we showed that bisphenol A (BPA) had oestrogen-like effects in bird embryos, causing malformations of the oviducts in Japanese quail (Coturnix japonica) and feminisation of the left testis in chicken (Gallus domesticus). In this study

  • 33.
    Hallgren, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Characterization of the tg(rgs4:mCherry) zebrafish line2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Cell-to-cell communication is one of the fundamental requisites of making multicellular organisms. G protein-coupled receptors (GPCRs) are one of the most abundant receptor-types within vertebrates. They canonically mediate their signal via hetrotrimeric G proteins, and G protein signaling is regulated by regulators of G protein-signaling (RGS). One of these RGS proteins, RGS4, is preferentially expressed in the central nervous system of humans and has been strongly connected to dopaminergic signaling, along with a number of severe neuronal diseases. rgs4 is not well studied in the model organism Danio rerio, the zebrafish, with only two publications. In this project, a newly constructed transgenic line, tg(rgs4:mCherry), with the fluorophore mCherry regulated by the promoter element of rgs4 was characterized in order to investigate fidelity to endogenous rgs4 expression and the utility of the transgenic line. The mCherry expression is apparent by 48 hours post fertilization, and expression is found mainly in neuronal tissue. Cell bodies are visible only in some labeled areas, while other areas show a more diffuse signal indicative of projections. There is only one transgenically labeled area that also unambiguously expresses rgs4; the pronephric tubule. This line is therefore not particularly well suited for rgs4-specifc studies, but this does not discredit the fidelity of the construct. A transgenic line made with a site-directed technique would most likely confer the fidelity of the promoter to the expression of the fluorophore. A way of increasing the labeling resolution includes exchanging the mCherry fluorophore for one with stronger signal and a lower tendency to aggregate, e.g. eGFP. Increasing the resolution of the characterization, e.g. to the level of sub-nuclei or neuronal types, would serve to enhance the utility of the line. As it is, the tg(rgs4:mCherry) zebrafish line has limited uses, and yet it is not without them.

  • 34.
    Hallgren, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology. Södertörns Högskola.
    Effects of an endocrine disruptor on anxiety behaviour in fish: Examples from zebrafish and guppy2013In: International Behavioral Neuroscience Society: Annual Meeting Program and Abstracts, 2013, 32-33 p.Conference paper (Refereed)
    Abstract [en]

    Animal behaviours such as foraging, predator avoidance, migration, exploration and reproduction are all essential for the survival of the individual as well as the population. Behaviours are integrated end-points of several physiological factors affected by the biotic, social and a-biotic environment, and involves the central nervous system, muscular control, the different senses and a number of hormones. Anthropogenic chemicals released from e.g. agriculture, industrial production, forestry and sewage treatment may interfere with these physiological processes and ultimately cause disturbances in animal behaviour. Disruption of the endocrine system has caught much attention in aquatic toxicology, with much focus on disruption of reproductive behaviour and fertility of exposed fishes. However, mammalian examples suggest that the hormonal axis dealing with the coping of stress (Hypothalamo-Pituitary-Adrenal axis) also is very sensitive to endocrine disruptors. Tests examining stress related behaviours such as fear, anxiety, shoaling and exploration have recently been developed for fish models such as zebrafish. These tests have been suggested as useful tools in development of new psychoactive pharmaceuticals but can also be applied to behaviour toxicology . Our studies using two of these behaviour tests, the novel tank diving test and shoaling test, on Zebrafish and Guppy show that low doses of the synthetic oestrogen Ethynylestradiol-17α can affect both anxiety and shoal adhesive behaviour of exposed fish. We suggest that in fishes the susceptibility to potent endocrine disruptors in stress related behaviours is equal to that of reproductive end-points. 

  • 35.
    Hallgren, Stefan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology. Uppsala University.
    Fredriksson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Viberg, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Transcriptional alterations of cholinergic and dopaminergic genes in the CNS of mice neonatally exposed to PFOS and PBDE99.2015Conference paper (Other academic)
  • 36.
    Hasse, Dirk
    et al.
    University of Rostock, Germany .
    Mikkat, Stefan
    Hagemann, Martin
    Bauwe, Hermann
    Alternative splicing produces an H-protein with better substrate properties for the P-protein of glycine decarboxylase.2009In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 276, no 23Article in journal (Refereed)
    Abstract [en]

    Several thousand plant genes are known to produce multiple transcripts, but the precise function of most of the alternatively encoded proteins is not known. Alternative splicing has been reported for the H-protein subunit of glycine decarboxylase in the genus Flaveria. H-protein has no catalytic activity itself but is a substrate of the three enzymatically active subunits, P-, T- and L-protein. In C(4) species of Flaveria, two H-proteins originate from single genes in an organ-dependent manner. Here, we report on differences between the two alternative H-protein variants with respect to their interaction with the glycine-decarboxylating subunit, P-protein. Steady-state kinetic analyses of the alternative Flaveria H-proteins and artificially produced 'alternative' Arabidopsis H-proteins, using either pea mitochondrial matrix extracts or recombinant cyanobacterial P-protein, consistently demonstrate that the alternative insertion of two alanine residues at the N-terminus of the H-protein elevates the activity of P-protein by 20%in vitro, and could promote glycine decarboxylase activity in vivo.

  • 37.
    Helmersson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Molecular identification of mosquito species: Evaluation of a rapid DNA extraction method together with DNA barcoding as a tool for identification of species2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The current method to determine a mosquito specimen to a certain species is by morphological keys basically following the taxonomy developed by Carl Linnaeus in the 1700. Since Watson and Crick presented their model of the double-helix DNA in 1953, a new era of molecular based taxonomic studies have revolutionized the field. The revolution is not in terms of how the classification of species is done but how the biological diversity is seen. However, morphological, ecological and behavioral characteristics are still important and are used together with the information a gene or whole genome can give. DNA barcoding is one of the promising methods for molecular identification. A small segment of a gene, approximately 400-1000 base pairs (bp), are examined by a Polymerase chain reaction (PCR) and sequencing. Like the barcodes in the grocery store these sequences work like unique ID: s for every species. This thesis shows how a fast DNA extraction method could be combined with DNA barcoding to get a 658-bp segment of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) from different species of the mosquito family Culicidae. A total of 15 thoraxes or wings, from individual specimen of mosquitoes, were examined and 11 different barcode sequences could be retrieved. Six correspond to already published COI sequences and could therefore be determined to the species level, including a sequence from a new species for Sweden, Aedes (Ochlerotatus) nigrinus. All mosquitoes were collected during the national inventory of species in summer of 2012 in Sweden, ”Myggjakten”, and have been morphological examined by experts at the National Veterinary Institute (SVA) prior to molecular determination. This thesis also highlights the importance of building a reference library of barcode sequences, so DNA barcoding could become an effective diagnostic tool. Inventory projects like “Myggjakten” may, if repeated, provide excellent material for such a library collection of barcode data.

  • 38.
    Hendriks, Hester S.
    et al.
    Utrecht University.
    Koolen, Lucas A. E.
    Utrecht University.
    Dingemans, Milou M. L.
    Utrecht University.
    Viberg, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Lee, Iwa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Leonards, Pim E.G.
    VU University, Amsterdam.
    Ramakers, Geert M.J.
    University Medical Center Utrecht.
    Westerink, Remco H.S.
    Utrecht University.
    Effects on neonatal exposure to the flame retardant tetrabrombisphenol-A, aluminum diethylphosphinate or zinc stannate on long-term, potentiation and synaptic protein levels in mice2014In: Archives of Toxicology, ISSN 0340-5761, E-ISSN 1432-0738, Vol. 89, no 12, 2345-2354 p.Article in journal (Refereed)
    Abstract [en]

    Brominated flame retardants such as tetrabromobisphenol-A (TBBPA) may exert (developmental) neurotoxic effects. However, data on (neuro)toxicity of halogen-free flame retardants (HFFRs) are scarce. Recent in vitro studies indicated a high neurotoxic potential for some HFFRs, e.g., zinc stannate (ZS), whereas the neurotoxic potential of other HFFRs, such as aluminum diethylphosphinate (Alpi), appears low. However, the in vivo (neuro)toxicity of these compounds is largely unknown. We therefore investigated effects of neonatal exposure to TBBPA, Alpi or ZS on synaptic plasticity in mouse hippocampus. Male C57bl/6 mice received a single oral dose of 211 µmol/kg bw TBBPA, Alpi or ZS on postnatal day (PND) 10. On PND 17–19, effects on hippocampal synaptic plasticity were investigated using ex vivo extracellular field recordings. Additionally, we measured levels of postsynaptic proteins involved in long-term potentiation (LTP) as well as flame retardant concentrations in brain, muscle and liver tissues. All three flame retardants induced minor, but insignificant, effects on LTP. Additionally, TBBPA induced a minor decrease in post-tetanic potentiation. Despite these minor effects, expression of selected synaptic proteins involved in LTP was not affected. The flame retardants could not be measured in significant amounts in the brains, suggesting low bioavailability and/or rapid elimination/metabolism. We therefore conclude that a single neonatal exposure on PND 10 to TBBPA, Alpi or ZS does affect neurodevelopment and synaptic plasticity only to a small extent in mice. Additional data, in particular on persistence, bioaccumulation and (in vivo) toxicity, following prolonged (developmental) exposure are required for further (human) risk assessment.

  • 39.
    Jepson, Paul D.
    et al.
    Zool Soc London, Inst Zool, London NW1 4RY, England..
    Deaville, Rob
    Zool Soc London, Inst Zool, London NW1 4RY, England..
    Barber, Jonathan L.
    Ctr Environm Fisheries & Aquaculture Sci, Lowestoft NR33 0HT, Suffolk, England..
    Aguilar, Alex
    Univ Barcelona, Dept Anim Biol, Barcelona, Spain.;Univ Barcelona, Biodivers Res Inst IRBio, Barcelona, Spain..
    Borrell, Asuncion
    Univ Barcelona, Dept Anim Biol, Barcelona, Spain.;Univ Barcelona, Biodivers Res Inst IRBio, Barcelona, Spain..
    Murphy, Sinead
    Zool Soc London, Inst Zool, London NW1 4RY, England..
    Barry, Jon
    Ctr Environm Fisheries & Aquaculture Sci, Lowestoft NR33 0HT, Suffolk, England..
    Brownlow, Andrew
    Scottish Marine Anim Stranding Scheme, SRUC Vet Serv Drummondhill, Inverness IV2 4JZ, Scotland..
    Barnett, James
    Univ Exeter, Environm & Sustainabil Inst, Penryn TR10 9EZ, Cornwall, England..
    Berrow, Simon
    Galway Mayo Inst Technol, Marine & Freshwater Res Ctr, Galway, Ireland..
    Cunningham, Andrew A.
    Zool Soc London, Inst Zool, London NW1 4RY, England..
    Davison, Nicholas J.
    Scottish Marine Anim Stranding Scheme, SRUC Vet Serv Drummondhill, Inverness IV2 4JZ, Scotland..
    ten Doeschate, Mariel
    Scottish Marine Anim Stranding Scheme, SRUC Vet Serv Drummondhill, Inverness IV2 4JZ, Scotland..
    Esteban, Ruth
    CIRCE, Conservat Informat & Res Cetaceans, Algeciras 11390, Spain..
    Ferreira, Marisa
    Univ Minho, Dept Biol, Soc Portuguesa Vida Selvagem, Marine Anim Tissue Bank Portugal, P-4719 Braga, Portugal.;CESAM, Oporto, Portugal..
    Foote, Andrew D.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Genov, Tilen
    Morigenos Slovenian Marine Mammal Soc, Piran 6330, Slovenia.;Univ Primorska, Sci & Res Ctr, Inst Biodivers Studies, Koper, Slovenia.;Univ Primorska, Fac Math Nat Sci & Informat Technol, Dept Biodivers, Koper, Slovenia..
    Gimenez, Joan
    CSIC, EBD, Dept Conservat Biol, Seville 42092, Spain..
    Loveridge, Jan
    Cornwall Wildlife Trust Marine Strandings Network, Truro TR4 9DJ, England..
    Llavona, Angela
    Coordinadora Estudio Mamiferos Marinos CEMMA, Gondomar 36380, Pontevedra, Spain..
    Martin, Vidal
    Soc Estudios Cetaceos Canarias SECAC, Lanzarote, Spain..
    Maxwell, David L.
    Ctr Environm Fisheries & Aquaculture Sci, Lowestoft NR33 0HT, Suffolk, England..
    Papachlimitzou, Alexandra
    Ctr Environm Fisheries & Aquaculture Sci, Lowestoft NR33 0HT, Suffolk, England..
    Penrose, Rod
    Marine Environm Monitoring, Cardigan SA43 2PS, Ceredigion, England..
    Perkins, Matthew W.
    Zool Soc London, Inst Zool, London NW1 4RY, England..
    Smith, Brian
    Nat Hist Museum, London SW7 5BD, England..
    de Stephanis, Renaud
    CSIC, EBD, Dept Conservat Biol, Seville 42092, Spain..
    Tregenza, Nick
    Cornwall Wildlife Trust Marine Strandings Network, Truro TR4 9DJ, England..
    Verborgh, Philippe
    CIRCE, Conservat Informat & Res Cetaceans, Algeciras 11390, Spain..
    Fernandez, Antonio
    Univ Las Palmas Gran Canaria, Fac Vet, Gran Canaria, Spain..
    Law, Robin J.
    Zool Soc London, Inst Zool, London NW1 4RY, England.;Ctr Environm Fisheries & Aquaculture Sci, Lowestoft NR33 0HT, Suffolk, England..
    PCB pollution continues to impact populations of orcas and other dolphins in European waters2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, 18573Article in journal (Refereed)
    Abstract [en]

    Organochlorine (OC) pesticides and the more persistent polychlorinated biphenyls (PCBs) have well-established dose-dependent toxicities to birds, fish and mammals in experimental studies, but the actual impact of OC pollutants on European marine top predators remains unknown. Here we show that several cetacean species have very high mean blubber PCB concentrations likely to cause population declines and suppress population recovery. In a large pan-European meta-analysis of stranded (n = 929) or biopsied (n = 152) cetaceans, three out of four species:-striped dolphins (SDs), bottlenose dolphins (BNDs) and killer whales (KWs) had mean PCB levels that markedly exceeded all known marine mammal PCB toxicity thresholds. Some locations (e.g. western Mediterranean Sea, south-west Iberian Peninsula) are global PCB "hotspots" for marine mammals. Blubber PCB concentrations initially declined following a mid-1980s EU ban, but have since stabilised in UK harbour porpoises and SDs in the western Mediterranean Sea. Some small or declining populations of BNDs and KWs in the NE Atlantic were associated with low recruitment, consistent with PCB-induced reproductive toxicity. Despite regulations and mitigation measures to reduce PCB pollution, their biomagnification in marine food webs continues to cause severe impacts among cetacean top predators in European seas.

  • 40.
    Kalathil, Aravind Nambiar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The effect of Magnetic Fields on Dictyostelium discoideum, Osteoblasts and Fibroblasts2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The effect of EM waves on cells has been a subject of growing interest for many years. In this project we tried to recreate the increased proliferation rate noticed in the Dictyostelium discoideum.

    The effect was not initially observed in the osteoblasts, since the experiments were attempted without a complete understanding of all the parameters involved that increased the proliferation rate.

    However, with the fibroblast cell, a similar trendline was achieved, with the highest difference in growth peaking at 22% using a magnetic field of 20Hz and 2300μT.

    In this project we try to explore the implications of such an effect, why it refused to work with one cell line, and why it worked with another, even though the effect was not as pronounced as it was with the amoebas. 

  • 41.
    Karthikraj, Karthikraj
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Crosstalk between DNA repair and chromatin modifications2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 42.
    Kellner, Martin
    et al.
    Sodertorn Univ, Sch Nat Sci Technol & Environm Studies, Sodertorn, Sweden.
    Porseryd, Tove
    Sodertorn Univ, Sch Nat Sci Technol & Environm Studies, Sodertorn, Sweden.
    Hallgren, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Porsch-Hällström, Inger
    Sodertorn Univ, Sch Nat Sci Technol & Environm Studies, Sodertorn, Sweden.
    Hansen, S.H.
    Univ Copenhagen, Fac Hlth & Med Sci, Dept Pharm, DK-1168 Copenhagen, Denmark.
    Olsén, K. Håkan
    Sodertorn Univ, Sch Nat Sci Technol & Environm Studies, Sodertorn, Sweden.
    Waterborne citalopram has anxiolytic effects and increases locomotor activity in the three-spine stickleback (Gasterosteus aculeatus)2016In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 173, 19-28 p.Article in journal (Refereed)
    Abstract [en]

    Citalopram is an antidepressant drug, which acts by inhibiting the re-uptake of serotonin from the synaptic cleft into the pre-synaptic nerve ending. It is one of the most common drugs used in treatment of depression, it is highly lipophilic and frequently found in sewage treatment plant effluents and surface waters around the world. Citalopram and other selective serotonin re-uptake inhibitors have, at concentrations that occur in nature, been shown to have behavioural as well as physiological effects on fish and other animals. This study is the result of several different experiments, intended to analyse different aspects of behavioural effects of chronic citalopram exposure in fish. Our model species the three-spine stickleback is common in the entire northern hemisphere and is considered to be a good environmental sentinel species. Female three-spine sticklebacks were exposed to 0, 1.5 and 15 μg/l nominal concentrations of citalopram for 21 days and subjected to the novel tank (NT) diving test. In the NT test, the fish exposed to 1.5 μg/l, but not the 15 μg/l fish made a significantly higher number of transitions to the upper half and stayed there for significantly longer time than the fish exposed to 0 μg/l. The 15 μg/l group, however, displayed a significantly lower number of freeze bouts and a shorter total freezing time. The test for locomotor activity included in the NT test showed that fish treated with 1.5 and 15 μg/l displayed a significantly higher swimming activity than control fish both 5–7 and 15–17 minutes after the start of the experiment. In the next experiment we compared fish exposed to 1.5 μg/l and 0.15 μg/l to pure water controls with regard to shoaling intensity and found no effect of treatment. In the final experiment the propensity of fish treated with 1.5 μg/l to approach an unknown object and aggressive behaviour was investigated using the Novel Object test and a mirror test, respectively. The exposed fish ventured close to the unknown object significantly more often and stayed there for significantly longer time than unexposed fish. The aggression test yielded no statistically significant effects. It is concluded that citalopram changes the behaviour of the three-spine stickleback in a way that is likely to have ecological consequences and that it must not be considered an environmentally safe pharmaceutical.

  • 43.
    Kohout, Manuel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Prioritizing islands for the eradication of invasive predators: Which islands in the Western Indian Ocean should be protected first2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Islands, constituting merely 5% of our planet’s land area, hold more than 20% of all existing terrestrial plant and vertebrate species. Dauntingly, islands are also among the places most severely affected by the extinction crisis we are facing today. Next to habitat destruction, the greatest threat to island biodiversity is invasive predators and the most effective way to deal with them is their removal. Crucially, eradication is an absolutely essential prerequisite for any subsequent restoration to be successful. In an aspiration to add to the gradually emerging efforts of channelling limited resources to the islands in most urgent need of protection, this study informs about island priorities in the Western Indian Ocean for the eradication of rats (Rattus spp.), cats (Felis catus) and mice (Mus musculus). Considering 318 islands within the region and using 77 affected bird species as surrogates for an island’s total conservation value, the overall strategy of the approach is one of return on investment, i.e. of conservation gain divided by conservation cost. The method strives to be complex and flexible enough to be adjustable to the specific goals of any conservation practitioner in the region, while, at the same time, simple and transparent enough, to be repeatable anywhere in the world. Novel is the inclusion of two variables increasing along probability curves, and measuring an island’s inundation and reinvasion risk. The result of the triage is a set of robust lists presenting the most important islands for immediate conservation actions. 

  • 44.
    Kunce, Warren
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Stoks, Robby
    Univ Leuven, Lab Aquat Ecol Evolut & Conservat, Leuven, Belgium..
    Johansson, Frank
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Single and mixture impacts of two pyrethroids on damselfly predatory behavior and physiological biomarkers2017In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 190, 70-77 p.Article in journal (Refereed)
    Abstract [en]

    Direct mortality due to toxicity of single pesticide exposure along a concentration gradient, while the most common, is only one important parameter for assessing the effects of pesticide contamination on aquatic ecosystems. Sub-lethal toxicity can induce changes in an organism's behavior and physiology that may have population -level ramifications and consequences for ecosystem health. Additionally, the simultaneous detection of multiple contaminants in monitored watersheds stresses the importance of gaining a greater understanding of the toxicities of combined exposures, particularly at low, environmentally relevant concentrations. Using larvae of the Azure Damselfly (Coenagrion paella), we conducted a combined exposure investigation of two widely-used pyrethroid insecticides presumed to share the same neurotoxic mechanism of action, and estimated their effect on predatory ability, mobility and three physiological biomarkers (Glutathione S-transferase; GST, respiratory electron transport system; ETS, and malondialdehyde; MDA). Deltamethrin exposure (0.065 mu g/L and 0.13 mu g/L) was found to reduce the predatory ability, but it did not affect the larvae's mobility. Esfenvalerate exposure (0.069 mu g/L and 0.13 mu g/L), on the other hand, induced no significant changes in predatory ability or mobility. The decrease in predatory ability after the combination exposure (0.067 mu g/L deltamethrin and 0.12 mu g/L. esfenvalerate) did not significantly differ from the impact of the single deltamethrin exposures. Glutathione-S-transferase was induced after single esfenvalerate exposure and the lower deltamethrin concentration exposure, but seemingly inhibited after exposure to the higher concentration of deltamethrin as well as the combination of both pyrethroids. Our data indicate that sub-lethal exposure to deltamethrin reduces predatory ability and suggest that sub-lethal combined exposure to deltamethrin and esfenvalerate inhibits the GST detoxification pathway. These effects can eventually result in a lower emergence of adults from contaminated ponds.

  • 45.
    Landis, Susanne H.
    et al.
    Helmholtz Ctr Ocean Res Kiel GEOMAR, Evolutionary Ecol Marine Fishes, D-24105 Kiel, Germany..
    Sundin, Josefin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology.
    Rosenqvist, Gunilla
    Norwegian Univ Sci & Technol, Dept Biol, Ctr Biodivers Dynam, N-7491 Trondheim, Norway..
    Poirier, Maude
    Helmholtz Ctr Ocean Res Kiel GEOMAR, Evolutionary Ecol Marine Fishes, D-24105 Kiel, Germany..
    Jorgensen, Guro Oistensen
    Norwegian Univ Sci & Technol, Dept Biol, Ctr Biodivers Dynam, N-7491 Trondheim, Norway..
    Roth, Olivia
    Helmholtz Ctr Ocean Res Kiel GEOMAR, Evolutionary Ecol Marine Fishes, D-24105 Kiel, Germany..
    Female pipefish can detect the immune status of their mates2015In: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 69, no 12, 1917-1923 p.Article in journal (Refereed)
    Abstract [en]

    Given the ubiquity of the parasites and their important fitness consequences on mate and offspring condition, selection for the ability to distinguish healthy from parasitized potential mates is a key process to enhance Darwinian fitness. In this study, we experimentally evaluated how the immunological experience of two potential partners influences mate choice, using the sex-role-reversed pipefish Syngnathus typhle. We exposed S. typhle to immune challenges with heat-killed Vibrio bacteria and investigated whether the activation of the immune system determined mate preferences. Our results demonstrate that the immune status of the potential partners influenced female mate preference, such that females that were exposed to an immune challenge became choosy and favored unchallenged males. Males, however, did not show any preferences for female immune status. In this context, we discuss mate choice decisions and behavioral plasticity as a complex result of immune challenge, severity of infection, as well as trans-generational effects.

  • 46.
    Larsson, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Endocrine disruption of the fungicide propiconazole in the frog Xenopus tropicalis: Effects on the aromatase activity and egg development2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Amphibian populations around the world are decreasing, and endocrine disrupting chemicals have been suggested as a part of the problem. The fungicide propiconazole is used in agriculture in many countries. It works as a fungicide by inhibiting CYP51, affecting the fungi cell membrane, but it has also been proven to inhibit aromatase, CYP19. Aromatase converts androgens to estrogen and is important for sexual differentiation in the early development and in reproduction in vertebrates. The aim of this study was to investigate the effect of propiconazole on the aromatase activity in brains from the West African clawed frog (Xenopus tropicalis), after larval and adult exposure and on aromatase activity in ovaries after adult exposure. Furthermore, effects on egg development was determined after adult exposure.

    Tadpoles were exposed to propiconazole (0, 25, and 250 µg/L) from three days after hatching until metamorphosis. In a former study, female adult X. tropicalis were exposed to 0 and 250 µg/L propiconazole during 4 weeks. The result of the aromatase activity measurements showed that 250 µg/L propiconazole increased brain aromatase activity after larval exposure. Brain and ovarian aromatase activity was also increased compared to the controls after adult exposure to 250µg/L propiconazole. The increased aromatase activity could reflect a compensatory response to decreased estrogen levels. Propiconazole had a significant impact on egg development, with an increased proportion of atretic oocytes and a decreased proportion of vitellogenic oocytes compared to the controls. The effect on egg development seems to be the result of a low estrogen level. The results suggest that exposure to propiconazole 250 µg/L could have a negative impact on X. tropicalis fertility.  Further studies to determine impacts of environmental exposure concentrations are needed to evaluate the risk of azoles to amphibian reproduction.

    The full text will be freely available from 2019-06-25 12:35
  • 47. Leblond, Jeffrey D.
    et al.
    Dahmen, Aaron S.
    Lebret, Karen
    Lund University.
    Rengefors, Karin
    Sterols of the Green-Pigmented, Freshwater Raphidophyte, Gonyostomum semen, from Scandinavian Lakes2013In: Journal of Eukaryotic Microbiology, ISSN 1066-5234, E-ISSN 1550-7408, Vol. 60, no 4, 399-405 p.Article in journal (Refereed)
    Abstract [en]

    Sterols are a class of membrane-reinforcing, ringed lipids which have a long history of examination in algae as a means of deriving chemotaxonomic relationships and as potential lipidic biomarkers. The Raphidophyceae represent a class of harmful, bloom-forming, marine and freshwater algae. To date, there have been four published examinations of their sterol composition, focusing primarily on brown-pigmented, marine species within the genera, Chattonella, Fibrocapsa, and Heterosigma. Lacking in these examinations has been the species Gonyostomum semen Ehrenb., which is a green-pigmented, freshwater raphidophyte with a worldwide distribution. The goal of this study was to examine the sterol composition of this nuisance alga, determine the potential of using its sterol profile as a biomarker, and finally to determine if there is any intraspecific variability between isolates. We have examined 21 isolates of G. semen from a number of Scandinavian lakes, and all were found to produce two major sterols, 24-ethylcholesta-5,22E-dien-3-ol and 24-ethylcholest-5-en-3-ol, and 24-methylcholest-5-en-3-ol as a minor sterol; the presence of 24-ethylcholesta-5,22E-dien-3-ol differentiates G. semen from brown-pigmented, marine raphidophytes which generally lack it. The results of this study indicate that isolates of G. semen from geographically separate lakes across Finland and Scandinavia have the same sterol biosynthetic pathway, and that there is no evolutionary divergence between the isolates with regard to sterol composition. The sterols of G. semen are not considered to be useful biomarkers for this particular organism because they are commonly found in other algae and plants.

  • 48.
    Lee, Iwa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Al-Refai, Ali
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Viberg, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Neonatal exposure to pesticides in mice alters neuroprotein levels important for the developing brain2014Conference paper (Other academic)
  • 49.
    Lee, Iwa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Eriksson, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Fredriksson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Buratovic, Sonja
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Lasley, Stephen
    Dept. of Cancer Biology and Pharmacology, University of Chicago College of Medicine.
    Viberg, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Single exposure to pesticides during brain development causes neurotoxic effects manifested as persistent behavior aberrations and neuroprotein alterations in mice2014Conference paper (Other academic)
  • 50.
    Lee, Iwa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology.
    Eriksson, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Fredriksson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Buratovic, Sonja
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Viberg, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology.
    Developmental neurotoxic effects of two pesticides: behavior and biomolecular studies on chlorpyrifos and carbaryl2015In: Toxicology and Applied Pharmacology, ISSN 0041-008X, E-ISSN 1096-0333, Vol. 288, no 3, 429-438 p.Article in journal (Refereed)
    Abstract [en]

    In recent times, an increased occurrence of neurodevelopmental disorders, such as neurodevelopmental delays and cognitive abnormalities has been recognized. Exposure to pesticides has been suspected to be a possible cause of these disorders, as these compounds target the nervous system of pests. Due to the similarities of brain development and composition, these pesticides may also be neurotoxic to humans. We studied two different pesticides, chlorpyrifos and carbaryl, which specifically inhibit acetylcholinesterase (AChE) in the nervous system. The aim of the study was to investigate if the pesticides can induce neurotoxic effects, when exposure occurs during a period of rapid brain growth and maturation. The results from the present study show that both compounds can affect protein levels in the developing brain and induce persistent adult behavior and cognitive impairments, in mice neonatally exposed to a single oral dose of chlorpyrifos (0.1, 1.0 or 5 mg/kg body weight) or carbaryl (0.5, 5.0 or 20.0 mg/kg body weight) on postnatal day 10. The results also indicate that the developmental neurotoxic effects induced are not related to the classical mechanism of acute cholinergic hyperstimulation, as the AChE inhibition level (8–12%) remained below the threshold for causing systemic toxicity. The neurotoxic effects are more likely caused by a disturbed neurodevelopment, as similar behavioral neurotoxic effects have been reported in studies with pesticides such as organochlorines, organophosphates, pyrethroids and POPs, when exposed during a critical window of neonatal brain development.

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