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  • 251. Bestill onlineKjøp publikasjonen >>
    Borutinskaite, Veronika Viktorija
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Klinisk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Characterization of proteins involved in differentiation and apoptosis of human leukemia and epithelial cancer cells2008Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Today, cancer is understood as an epigenetic as well as a genetic disease. The main epigenetic hallmarks of the cancer cell are DNA methylation and histone modifications. The latter changes may be an optimal target for novel anticancer agents. The main goal of using histone deacetylase inhibitors (HDACIs) would be restoration of gene expression of those tumor-suppressor genes that have been transcriptionally silenced by promoter-associated histone deacetylation. However, HDACIs have pleiotropic effects that we are only just starting to understand. These may also be responsible for the induction of differentiation, cell-cycle arrest and pro-apoptotic effects.

    There are now so many HDACIs available, with such different chemical structures and biological and biochemical properties, that it is hopeful that at least some of them will succeed, probably in combination with other agents or therapies.

    In our studies we focussed ourselves on studies some new HDACIs, that can be useful for treating cancers, including leukemia and epithelial cancer. To do that, we used novel HDACIs, like BML-210, and their combination with the differentiation inducer all-trans retinoic acid (ATRA). Cell differentiation and proliferation in general, and specific gene expression require de novo protein synthesis and/or post-translational protein modifications. So, we tried to identify proteins in general and specifically the proteins that could be important for the cell differentiation process, and when and where in the cell the proteins appear.

    We delineated that HDACIs inhibited leukemia (NB4 and HL-60) cell growth in a time- and dose-dependent way. Moreover, BML-210 blocked HeLa cell growth and promoted apoptosis in a time-dependent way. Combining of BML-210 with ATRA induced a differentiation process in leukemia cell lines that lead to apoptosis. This correlated with cell cycle arrest in G0/G1 stage and changes in expression of cell cycle proteins (p21, p53), transcription factors (NF-κB, Sp1) and their binding activity to consensus or specific promoter sequences. We also assessed histone modifications, i.e. H3 phosphorylation and H4 hyperacetylation due to HDACI, leading to chromatin remodeling and changes in gene transcriptions.

    We have also studied changes in protein maps caused by HDACIs and differentiation agents, identifying differences for a few proteins due to growth inhibition and induction of differentiation in NB4 cells using BML-210 alone or in combination with ATRA. These proteins are involved in cell proliferation and signal transduction, like Rab, actin and calpain. One of them was alpha-dystrobrevin (α-DB). To further study possible roles of the latter, we determined changes of α-DB protein isoform expression that correlated with induction of differentiation. We thus identified a novel ensemble of α-DB interacting proteins in promyelocytic leukemia cells, including tropomyosin 3, actin, tubulin, RIBA, STAT and others, being important in cytoskeleton reorganization and signal transduction. Using confocal microscopy, we determined that α-DB co-localizes with HSP90 and F-actin in NB4 and HeLa cells. We also revealed that it changes sub-cellular compartment after treatment with ATRA and/or BML-210. α-DB silencing affected F-actin expression in HeLa cells, further supporting the idea that α-DB is involved in cytoskeleton reorganization in cells. Altogether, our results suggest that α−DB may work as a structural protein during proliferation and differentiation processes of human cancer cells.

    Based on our findings, we suggest that HDACIs, like BML-210, can be promising anticancer agents, especially in leukemia treatment, by inducing apoptosis and regulating proliferation and differentiation through the modulation of histone acetylations and gene expression.

    Delarbeid
    1. The novel histone deacetylase inhibitor BML-210 exerts growth inhibitory, proapoptotic and differentiation stimulating effects on the human leukemia cell lines
    Åpne denne publikasjonen i ny fane eller vindu >>The novel histone deacetylase inhibitor BML-210 exerts growth inhibitory, proapoptotic and differentiation stimulating effects on the human leukemia cell lines
    Vise andre…
    2006 (engelsk)Inngår i: European Journal of Pharmacology, ISSN 0014-2999, Vol. 549, nr 1-3, s. 9-18Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Histone deacetylase inhibitors have a potent role in the strategy for the treatment of leukemias. BML-210 (N-(2-Aminophenyl)-N′ phenyloctanol diamine) is the novel histone deacetylase inhibitor, and its mechanism of action has not been characterized. In this study, we examined the in vitro effects of BML-210 on the human leukemia cell lines (NB4, HL-60, THP-1, and K562). We found that BML-210 inhibits the growth of all cell lines and promotes apoptosis in a dose- and time-dependent manner. BML-210 alone induces HL-60 and K562 cell differentiation (up to 30%) to granulocytes and erythrocytes, respectively, and in combination with differentiation agents — all-trans retinoic acid and hemin, markedly potentates it. Those treatments cause G1 arrest and histone H4 acetylation, affects transcription factor NF-κB and Sp1 binding activity to their consensus sequences, the p21 or the FasL promoters, and influences expression of Sp1, NF-κB, p21 and FasL. These findings suggest that BML-210 could be a promising antileukemic agent to induce apoptosis and to modulate differentiation through the modulation of histone acetylation and gene expression.

    Emneord
    Apoptosis; Differentiation; Histone deacetylase inhibitor; Leukemia; Transcription factors
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-13262 (URN)10.1016/j.ejphar.2006.08.010 (DOI)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30
    2. Apoptotic effects of the novel histone deacetylase inhibitor BML-210 on HeLa cells
    Åpne denne publikasjonen i ny fane eller vindu >>Apoptotic effects of the novel histone deacetylase inhibitor BML-210 on HeLa cells
    Manuskript (Annet vitenskapelig)
    Identifikatorer
    urn:nbn:se:liu:diva-13263 (URN)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30 Sist oppdatert: 2010-01-13
    3. Effects of retinoic acid and histone deacetylase inhibitor Bml-210 on protein expression in NB4 cells
    Åpne denne publikasjonen i ny fane eller vindu >>Effects of retinoic acid and histone deacetylase inhibitor Bml-210 on protein expression in NB4 cells
    2005 (engelsk)Inngår i: Biologija, ISSN 1392-0146, Vol. 4, s. 88-93Artikkel i tidsskrift (Fagfellevurdert) Published
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-13264 (URN)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30
    4. Multiple roles of alpha-dystrobrevin in human cancer cells during proliferation and differentiation processes
    Åpne denne publikasjonen i ny fane eller vindu >>Multiple roles of alpha-dystrobrevin in human cancer cells during proliferation and differentiation processes
    Manuskript (Annet vitenskapelig)
    Identifikatorer
    urn:nbn:se:liu:diva-13265 (URN)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30 Sist oppdatert: 2010-01-13
    5. Retinoic acid and histone deacelytase inhibitor BML-210 inhibit proliferation of human cervical cancer HeLa cells
    Åpne denne publikasjonen i ny fane eller vindu >>Retinoic acid and histone deacelytase inhibitor BML-210 inhibit proliferation of human cervical cancer HeLa cells
    2006 (engelsk)Inngår i: Annals of the New York Academy of Sciences, ISSN 0077-8923, Vol. 1091, s. 346-355Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Human papillomavirus (HPV) infection is believed to be the central cause of cervical cancer. The viral proteins E6 and E7 from high-risk HPV types prevent cells from differentiating apoptosis and inducing hyperproliferative lesions. Human cervical carcinoma HeLa cells contain integrated human papillomavirus type 18 (HPV-18). Retinoic acid (RA) is a key regulator of epithelial cell differentiation and a growth inhibitor in vitro of HeLa cervical carcinoma cells. Cellular responses to RA are mediated by nuclear retinoic acid receptors (RARs) and retinoid X receptors. On the other hand, histone deacetylase inhibitors have been shown to be chemopreventive agents for the treatment of cancer cells. In this article, we have examined the antiproliferative effect of RA and histone deacetylase inhibitor BML-210 on HeLa cells, and particularly the effects on protein expression that may be involved in the cell cycle control and apoptosis. Our data suggest that a combination of RA and BML-210 leads to cell growth inhibition with subsequent apoptosis in a treatment time-dependent manner. We confirm that BML-210 alone or in combination with RA causes a marked increase in the level of p21. The changes in the p53 level are under the influence of p38 phosphorylation. We also discovered that the histone deacetylase inhibitor BML-210 causes increased levels of anti-apoptotic protein Bcl-2 and phosphorylated p38 MAP Kinase; the latter link in cell cycle arrest with response to extracellular stimuli. Our results suggest that RA and BML-210 are involved in different signaling pathways that regulate cell cycle arrest and lead to apoptosis of HeLa cells.

    Emneord
    histone deacetylase inhibitor, proliferation, p53, p21
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-13266 (URN)10.1196/annals.1378.079 (DOI)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30 Sist oppdatert: 2009-05-07
    6. The histone deacetylase inhibitor FK228 distinctly sensitizes the human leukemia cells to retinoic acid-induced differentiation
    Åpne denne publikasjonen i ny fane eller vindu >>The histone deacetylase inhibitor FK228 distinctly sensitizes the human leukemia cells to retinoic acid-induced differentiation
    Vise andre…
    2006 (engelsk)Inngår i: Annals of the New York Academy of Sciences, ISSN 0077-8923, Vol. 1091, s. 368-384Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    FK228 (depsipeptide) is a novel histone deacetylase inhibitor (HDACI) that has shown therapeutical efficacy in clinical trials for malignant lymphoma. In this article, we examined in vitro effects of FK228 on human leukemia cell lines, NB4 and HL-60. FK228 alone (0.2–1 ng/mL) inhibited leukemia cell growth in a dose-dependent manner and induced death by apoptosis. FK228 had selective differentiating effects on two cell lines when used for 6 h before induction of granulocytic differentiation by retinoic acid (RA) or in combination with RA. These effects were accompanied by a time- and dose-dependent histone H4 hyper-acetylation or histone H3 dephosphorylation and alterations in DNA binding of NF-κB in association with cell death and differentiation. Pifithrin-α (PFT), an inhibitor of p53 transcriptional activity, protected only NB4 cells with functional p53 from FK228-induced apoptosis and did not interfere with antiproliferative activity in p53-negative HL-60 cells. In NB4 cells, PFT inhibited p53 binding to the p21 (Waf1/Cip1) promotor and induced DNA binding of NF-κB leading to enhanced cell survival. Thus, beneficial effects of FK228 on human promyelocytic leukemia may be exerted through the induction of differentiation or apoptosis via histone modification and selective involvement of transcription factors, such as NF-κB and p53.

    Emneord
    differentiation, histone deacetylase inhibitor, leukemia, NF-κB, p53
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-13267 (URN)10.1196/annals.1378.081 (DOI)
    Tilgjengelig fra: 2008-05-30 Laget: 2008-05-30 Sist oppdatert: 2011-01-11
    Fulltekst (pdf)
    FULLTEXT01
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    COVER01
  • 252.
    Bosagna, Carlos Guerrero
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Developmental and Epigenetic Origins of Male Reproductive Pathologies2015Inngår i: The Epigenome and Developmental Origins of Health and Disease / [ed] Cheryl Rosenfeld, Elsevier, 2015, 1, s. 171-189Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Transgenerational epigenetic inheritance has gained increased attention due to the possibility that exposure to environmental toxicants or other stressors can induce long-lasting changes in lineages of organisms. The mechanism involves exposure of pregnant females and induction of germline epigenetic alterations in their developing embryos. This early developmental exposure generates phenotypic alterations in the adults. The germline epigenomic changes produced are then transmitted to future generations and associate with disease phenotypes in the unexposed individuals of subsequent generations. Exposures to environmental toxicants such as fungicides, pesticides, or plastic compounds have been shown in rodents to produce abnormal reproductive or metabolic phenotypes that are transgenerationally transmitted. These include transgenerational increases in the incidence of obesity, polycystic ovary syndrome (PCOS)-like symptoms, pregnancy defects, or germ cell apoptosis. Importantly, the increased incidence of these transgenerationally transmitted diseases in response to environmental exposures in animal models is sometimes drastic. The current evidence on transgenerational epigenetic inheritance observed in animal models allows predicting that environmental exposures of today's inhabitants of the world may affect the incidence of noninfectious diseases in future generations, which would be correlated with long-lasting alterations in the epigenome. The present chapter summarizes the evidence to date for transgenerational epigenetic inheritance, in both humans and animal models.

  • 253.
    Bouwman, Henk
    et al.
    Nort-West University, South Africa.
    Krátká, M
    Masaryk University, Czech Republic.
    Choong Kwet Yive, Nee Sun
    University of Mauritius, Mauritius.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Klanova, Jana
    Masaryk University, Czech Republic.
    Do POPs Transfer from Plastic Marine Debris to Coral on Tropical Islands?2014Inngår i: Organohalogen Compounds, ISSN 1026-4892, Vol. 76, s. 1352-1355Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 254.
    Bouwman, Henk
    et al.
    North-West University, South Africa.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Louette, Michel
    Royal Museum for Central Africa, Belgium.
    Using ringing data to update the continental distributions of the subspecies of the Lesser Black-Backed Gull2012Inngår i: Afring News, ISSN 2222-341X, Vol. 41, s. 13-15Artikkel i tidsskrift (Fagfellevurdert)
  • 255.
    Bouwman, Hindrik
    et al.
    North West University, South Africa .
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Sun Choong Kwet Yive, Nee
    Mauritian Wildlife Fdn, Mauritius .
    Loken, Katharina
    Norwegian School Vet Science, Norway .
    Utne Skaare, Janneche
    Norwegian School Vet Science, Norway .
    Polder, Anuschka
    Norwegian School Vet Science, Norway .
    First report of chlorinated and brominated hydrocarbon pollutants in marine bird eggs from an oceanic Indian Ocean island2012Inngår i: Environmental Research, ISSN 0013-9351, E-ISSN 1096-0953, Vol. 118, s. 53-64Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the worlds third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560 km east of the island of Mauritius. Sigma PCBs had the highest levels (2.2 and 2.6 ng/g wm, wet mass; 20 and 19 ng/g lm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then Sigma DDT (1.9 and 3.1 ng/g wm; 17 and 23 ng/g lm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0 ng/g lm). Sigma Chlordanes (0.094 and 0.15 ng/g wm; 0.48 and 0.73 ng/g lm) and Sigma toxaphenes (0.26 and 0.61 ng/g wm; 2.4 and 5.9 ng/g lm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07 ng/g wm; 0.7 and 0.7 ng/g lm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Sigma chlordanes and Sigma toxaphenes, as well as CB105, -108 and -157. p,p-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site.

    Fulltekst (pdf)
    fulltext
  • 256.
    Bragde, Hanna
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Ryhov Cty Hosp, Sweden.
    Jansson, Ulf
    Ryhov Cty Hosp, Sweden.
    Fredrikson, Mats
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Grodzinsky, Ewa
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för läkemedelsforskning. Linköpings universitet, Medicinska fakulteten. Division of Forensic Genetics & Forensic Toxicology National Board of Forensic Medicine Linköping, Sweden.
    Söderman, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten. Ryhov Cty Hosp, Sweden.
    Celiac disease biomarkers identified by transcriptome analysis of small intestinal biopsies2018Inngår i: Cellular and Molecular Life Sciences (CMLS), ISSN 1420-682X, E-ISSN 1420-9071, Vol. 75, nr 23, s. 4385-4401Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Establishing a celiac disease (CD) diagnosis can be difficult, such as when CD-specific antibody levels are just above cutoff or when small intestinal biopsies show low-grade injuries. To investigate the biological pathways involved in CD and select potential biomarkers to aid in CD diagnosis, RNA sequencing of duodenal biopsies from subjects with either confirmed Active CD (n=20) or without any signs of CD (n=20) was performed. Gene enrichment and pathway analysis highlighted contexts, such as immune response, microbial infection, phagocytosis, intestinal barrier function, metabolism, and transportation. Twenty-nine potential CD biomarkers were selected based on differential expression and biological context. The biomarkers were validated by real-time polymerase chain reaction of eight RNA sequencing study subjects, and further investigated using an independent study group (n=43) consisting of subjects not affected by CD, with a clear diagnosis of CD on either a gluten-containing or a gluten-free diet, or with low-grade intestinal injury. Selected biomarkers were able to classify subjects with clear CD/non-CD status, and a subset of the biomarkers (CXCL10, GBP5, IFI27, IFNG, and UBD) showed differential expression in biopsies from subjects with no or low-grade intestinal injury that received a CD diagnosis based on biopsies taken at a later time point. A large number of pathways are involved in CD pathogenesis, and gene expression is affected in CD mucosa already in low-grade intestinal injuries. RNA sequencing of low-grade intestinal injuries might discover pathways and biomarkers involved in early stages of CD pathogenesis.

    Fulltekst (pdf)
    fulltext
  • 257.
    Brandao, Wesley Nogueira
    et al.
    Univ Sao Paulo, Brazil.
    Andersen, Monica Levy
    Fed Univ Sao Paulo UNIFESP EPM, Brazil.
    Palermo-Neto, Joao
    Univ Sao Paulo, Brazil.
    Peron, Jean Pierre
    Univ Sao Paulo, Brazil.
    Zager, Adriano
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Univ Sao Paulo, Brazil.
    Therapeutic treatment with Modafinil decreases the severity of experimental autoimmune encephalomyelitis in mice2019Inngår i: International Immunopharmacology, ISSN 1567-5769, E-ISSN 1878-1705, Vol. 75, artikkel-id 105809Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The psychostimulant drug modafinil has been used for many years for the treatment of sleep disorders. Recent studies have indicated that modafinil has immunomodulatory properties in the central nervous system (CNS) and peripheral immune cells. Thus, our aim was to determine the effects of in vivo therapeutic treatment with modafinil on the severity of clinical symptoms and immune response during the acute phase of experimental autoimmune encephalomyelitis (EAE), an experimental model of multiple sclerosis. Modafinil treatment, given after the onset of symptoms, resulted in an improvement of EAE symptoms and motor impairment, which was correlated with reduced cellular infiltrate and a decreased percentage of T helper (Th) 1 cells in the CNS. The spinal cord analysis revealed that modafinil treatment decreased interferon (IFN)-y and interleukin (IL)-6 protein levels and down regulated genes related to Th1 immunity, such as IFN-gamma and TBX21, without affecting Th17-related genes. Our research indicates that therapeutic modafinil treatment has anti-inflammatory properties in an EAE model by inhibiting brain Th1 response, and may be useful as adjuvant treatment for multiple sclerosis.

  • 258.
    Bravo, Gustavo A.
    et al.
    Harvard Univ, MA 02138 USA.
    Antonelli, Alexandre
    Harvard Univ, MA 02138 USA; Gothenburg Global Biodivers Ctr, Sweden; Univ Gothenburg, Sweden; Gothenburg Bot Garden, Sweden.
    Bacon, Christine D.
    Gothenburg Global Biodivers Ctr, Sweden; Univ Gothenburg, Sweden.
    Bartoszek, Krzysztof
    Linköpings universitet, Institutionen för datavetenskap, Statistik och maskininlärning. Linköpings universitet, Filosofiska fakulteten.
    Blom, Mozes P. K.
    Swedish Museum Nat Hist, Sweden.
    Huynh, Stella
    Univ Neuchatel, Switzerland.
    Jones, Graham
    Univ Gothenburg, Sweden.
    Knowles, L. Lacey
    Univ Michigan, MI 48109 USA.
    Lamichhaney, Sangeet
    Harvard Univ, MA 02138 USA.
    Marcussen, Thomas
    Univ Oslo, Norway.
    Morlon, Helene
    Ecole Normale Super Paris, France.
    Nakhleh, Luay K.
    Rice Univ, TX USA.
    Oxelman, Bengt
    Gothenburg Global Biodivers Ctr, Sweden; Univ Gothenburg, Sweden.
    Pfeil, Bernard
    Univ Gothenburg, Sweden.
    Schliep, Alexander
    Chalmers Univ Technol, Sweden; Univ Gothenburg, Sweden.
    Wahlberg, Niklas
    Lund Univ, Sweden.
    Werneck, Fernanda P.
    Inst Nacl de Pesquisas da Amazonia, Brazil.
    Wiedenhoeft, John
    Chalmers Univ Technol, Sweden; Univ Gothenburg, Sweden; Rutgers State Univ, NJ USA.
    Willows-Munro, Sandi
    Univ Kwazulu Natal, South Africa.
    Edwards, Scott V
    Harvard Univ, MA 02138 USA; Univ Gothenburg, Sweden; Chalmers Univ Technol, Sweden.
    Embracing heterogeneity: coalescing the Tree of Life and the future of phylogenomics2019Inngår i: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 7, artikkel-id e6399Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Building the Tree of Life (ToL) is a major challenge of modern biology, requiring advances in cyberinfrastructure, data collection, theory, and more. Here, we argue that phylogenomics stands to benefit by embracing the many heterogeneous genomic signals emerging from the first decade of large-scale phylogenetic analysis spawned by high-throughput sequencing (HTS). Such signals include those most commonly encountered in phylogenomic datasets, such as incomplete lineage sorting, but also those reticulate processes emerging with greater frequency, such as recombination and introgression. Here we focus specifically on how phylogenetic methods can accommodate the heterogeneity incurred by such population genetic processes; we do not discuss phylogenetic methods that ignore such processes, such as concatenation or supermatrix approaches or supertrees. We suggest that methods of data acquisition and the types of markers used in phylogenomics will remain restricted until a posteriori methods of marker choice are made possible with routine whole-genome sequencing of taxa of interest. We discuss limitations and potential extensions of a model supporting innovation in phylogenomics today, the multispecies coalescent model (MSC). Macroevolutionary models that use phylogenies, such as character mapping, often ignore the heterogeneity on which building phylogenies increasingly rely and suggest that assimilating such heterogeneity is an important goal moving forward. Finally, we argue that an integrative cyberinfrastructure linking all steps of the process of building the ToL, from specimen acquisition in the field to publication and tracking of phylogenomic data, as well as a culture that values contributors at each step, are essential for progress.

    Fulltekst (pdf)
    fulltext
  • 259.
    Brengdahl, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Differentiation of dispersive traits under a fluctuating range distribution in Asellus aquaticus2014Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    Knowledge about dispersion is of utmost importance for understanding populations’ reaction to changes in the environment. Expansion of a population range brings with it both spatial sorting and over time, spatial selection. This means that dispersion rates increases over time at the expanding edge. Most studies have so far been performed on continuously expanding populations. This study aims to bring more knowledge about dispersal biology in dynamic systems. I studied dispersal traits in two permanent and two seasonal vegetation habitats of an isopod (Asellus aquaticus), for which differentiation between habitat types has previously been shown. I quantified differences in displacement (dispersal rate) and three morphological traits, head angle (body streamline) and leg of the third and seventh pair of legs. Isopods from the seasonal vegetation had higher displacement rates than animals from permanent vegetation. This inclines that mechanisms driving spatial selection in expanding population ranges also exist in dynamic systems. The more streamlined isopods found in seasonal sites further points towards spatial sorting by dispersion capability. Because no effect of permanence was found on leg length and there was no correlation between streamlining and displacement, the higher dispersion among animals from seasonal habitats most likely derives from behavioral differences.

    Fulltekst (pdf)
    fulltext
  • 260.
    Brengdahl, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Dispersive trait expression of Asellus aquaticus from a rare cave habitat2016Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Dispersal influences several ecological and evolutionary processes, such as intraspecific competition, genetic drift and inbreeding. It can lead to phenotypic mismatch with the habitat when a locally adapted individual winds up in an environment with a divergent selection regime compared to the source habitat. The aim of this project was to compare dispersive traits in the freshwater isopod Asellus aquaticus from a cave habitat, with surface dwelling isopods collected upstream and downstream from the cave system. The subterranean stream (cave) represents a rare, geographically limited habitat which has a divergent selective pressure compared to the surrounding habitats. Experiments on dispersal were performed in the laboratory, in darkness with IR-equipment for visualization. Displacement was measured using one-dimensional test arenas. Compared to the surface phenotype, the cave phenotype was expected to have reduced fitness outside of the cave and unlikely to successfully disperse to new areas of similar suitable conditions. The results did not follow my main hypothesis that isopods from the cave would be less dispersive than individuals from the surface. The inconclusive results might derive from large variation in the data and divergent adaptations which yield similar expression of dispersal.

    Fulltekst (pdf)
    Dispersive trait expression of Asellus aquaticus from a rare cave habitat
  • 261.
    Brengdahl, Martin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Kimber, Christopher
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Maguire-Baxter, Jack
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Friberg, Urban
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Sex differences in life span: Females homozygous for the X chromosome do not suffer the shorter life span predicted by the unguarded X hypothesis2018Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 72, nr 3, s. 568-577Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Life span differs between the sexes in many species. Three hypotheses to explain this interesting pattern have been proposed, involving different drivers: sexual selection, asymmetrical inheritance of cytoplasmic genomes, and hemizygosity of the X(Z) chromosome (the unguarded X hypothesis). Of these, the unguarded X has received the least experimental attention. This hypothesis suggests that the heterogametic sex suffers a shortened life span because recessive deleterious alleles on its single X(Z) chromosome are expressed unconditionally. In Drosophila melanogaster, the X chromosome is unusually large (approximate to 20% of the genome), providing a powerful model for evaluating theories involving the X. Here, we test the unguarded X hypothesis by forcing D. melanogaster females from a laboratory population to express recessive X-linked alleles to the same degree as males, using females exclusively made homozygous for the X chromosome. We find no evidence for reduced life span or egg-to-adult viability due to X homozygozity. In contrast, males and females homozygous for an autosome both suffer similar, significant reductions in those traits. The logic of the unguarded X hypothesis is indisputable, but our results suggest that the degree to which recessive deleterious X-linked alleles depress performance in the heterogametic sex appears too small to explain general sex differences in life span.

    Fulltekst (pdf)
    fulltext
  • 262.
    Brengdahl, Martin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Kimber, Christopher
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Maguire-Baxter, Jack
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Malacrinò, Antonino
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Friberg, Urban
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Genetic Quality Affects the Rate of Male and Female Reproductive Aging Differently in Drosophila melanogaster2018Inngår i: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 192, nr 6, s. 761-772Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Males and females often maximize fitness by pursuing different reproductive strategies, with males commonly assumed to benefit more from increased resource allocation into current reproduction. Such investment should trade off with somatic maintenance and may explain why males frequently live shorter than females. It also predicts that males should experience faster reproductive aging. Here we investigate whether reproductive aging and life span respond to condition differently in male and female Drosophila melanogaster, as predicted if sexual selection has shaped male and female resource-allocation patterns. We manipulate condition through genetic quality by comparing individuals inbred or outbred for a major autosome. While genetic quality had a similar effect on condition in both sexes, condition had a much larger general effect on male reproductive output than on female reproductive output, as expected when sexual selection on vigor acts more strongly on males. We find no differences in reproductive aging between the sexes in low condition, but in high condition reproductive aging is relatively faster in males. No corresponding sex-specific change was found for life span. The sex difference in reproductive aging appearing in high condition was specifically due to a decreased aging rate in females rather than any change in males. Our results suggest that females age slower than males in high condition primarily because sexual selection has favored sex differences in resource allocation under high condition, with females allocating relatively more toward somatic maintenance than males.

    Fulltekst (pdf)
    fulltext
  • 263.
    Brian, Björn
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Microarray Technology for Kinetic Analysis of Vesicle Bound Receptor-Ligand Interactions2007Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    A proof-of-concept for a novel microarray used to study protein-ligand interaction in real-time using label-free detection is presented. Many of todays commercially available instruments lack the ability to immobilize membrane proteins. At the same time, the pharmaceutical industry develops drugs directed towards membrane-bound receptors. The need to study drug-target kinetics and to be able to screen for new medical substances is high. To study the biomolecular interactions in real-time, imaging surface plasmon resonance (iSPR) is used. A patterned sensor surface with hydrophobic barriers assisting in the piezodispensing of NeutrAvidin with complex-bound biotin-ssDNA is created. Histidine-tagged proteins are immobilized at the vesicle surface using divalent nitrilotriacetic acid. The concept of the vesicle immobilization, the protein-binding to vesicles and the protein-ligand interaction is initially studied using a Biacore instrument. The dissociation of the ligand IFNα2 from its receptor ifnar-2 (wt) are in accordance with the literature. In the imaging SPR experiments, it is found that the dissociation of IFNα2 from the ifnar-2 (wt) receptor is slower than expected, probably due to rebinding of the ligand. It is also found that imidazole is needed to avoid vesicle-vesicle interaction. The immobilization of proteins had to be done on-line i.e. when the vesicles were bound to the surface. Depending on the mixture of receptors at the vesicle surface the affinity for the ligand was changed. The results achieved were reproducible.

    Fulltekst (pdf)
    FULLTEXT01
  • 264.
    Brodd, Louise
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi.
    Behavioural differences between and within retriever breeds2016Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    The retriever breeds have the same origin and have long been used as a gundog for hunting of game, mostly birds. However, recently the retriever breeds have become a popular pet and show dog. This have affected the breeding of the dogs as the same traits are not bred for a gundog and a pet or show dog. Breeds as the Labrador retriever consists of a field- and common-type. The aim of this study is to investigate any differences between and within five of the retriever breeds in behaviours as retrieving, search and game reaction. 64 dogs undergoing the field trial Description of Function- Retriever was video recorded and scores from 430 dogs that have undergone field trials was obtained. Both differences between and within breeds were found when analysing both the videos and scores. In the video analysis, the Flatcoated retriever showed the most retrieving behaviours and was the most passive. The Nova scotia duck tolling retriever was in both the video and score analyses the most active breed. The Labrador retriever scored high in game reaction. The field- and mixed-types had almost always higher scores in behaviours linked to hunting, compared to the common-type. This supports findings that recent selection in breeding have a larger effect on behaviour than the origin uses of the dogs.

    Fulltekst (pdf)
    fulltext
  • 265.
    Brodd, Louise
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    The help-seeking behaviour of dogs (Canis familiaris)2014Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    During domestication, the dog( Canis familiaris), have become skilful in understanding human communication and also in communicating with humans. The wolf ( Canis lupus), is not as skilled with this interspecific communication. When dogs are faced with an unsolvable problem, they seek help from human by e.g. gazing at them. This behaviour has been studied and both age and breed group differences have been showed. In this study, we presented dogs with a task that consisted of a solvable and unsolvable problem in order to see if they gazed at their owner and/or an unfamiliar person for help. Although we did not find any difference in breed groups regarding gazing at humans, we did find that adult dogs (dogs older than 2 years) gazed more frequently at their owner and for a longer duration than adolescent dogs (6 months to 2 years). This may be because the adult dogs have more experience of this communication with humans, as they have lived longer with them. These findings empathize the bond between a dog and its owner that seems to grow stronger during the dogs’ life.

    Fulltekst (pdf)
    Ex 14/2868 Brodd Louise
  • 266. Bestill onlineKjøp publikasjonen >>
    Brodin Patcha, Veronika
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Pro- and anti-inflammatory regulation of β2 integrin signalling in human neutrophils2007Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The body is under constant attack from pathogens trying to slip by our immune defence. If the barrier is breached, invading pathogens enter the tissues and cause inflammation. During this process neutrophils, constituting the first line of defence, leave the bloodstream and seek out and kill the invading pathogens. The mechanisms leading to activation of receptors on neutrophils must be closely orchestrated. Pro- and anti-inflammatory substances can influence the outcome of the inflammation process by affecting the involved players. If not well balanced, inflammatory diseases, such as atherosclerosis and rheumatoid arthritis, can be the outcome.

    The aim of this thesis was to elucidate the effect of pro- (fMLP, Leukotriene B4, and Interleukin-8) and anti- (lipoxins, aspirin and statins) inflammatory substances on the β2 integrins, mediating adhesion of neutrophils both under “normal” conditions and during coronary artery disease. More specifically, the effect of these substances on the β2 integrins were studied in regard to: i) the activity (i.e. affinity and avidity) of β2 integrins, ii) the signalling capacity of β2 integrins (i.e. detected as release of arachidonic acid, and the production of reactive oxygen species, and iii) the signal transduction mediated by the β2 integrins (i.e. phosphorylation of Pyk2).

    The pro-inflammatory substances belong to the family of chemoattractants that induces transmigration and chemotaxis. A hierarchy exists between the different family members; the end-target chemoattractants (e.g. fMLP) being more potent than intermediary chemoattractants (e.g. IL-8 and LTB4). It was found that intermediary chemoattractants regulate β2 integrins by mainly affecting the avidity of β2 integrins. End-target chemoattractants on the other hand, affected the β2 integrins by increasing the avidity and the affinity, as well as their signalling capacity.

    The anti-inflammatory substances used in this study were the exogenous aspirin and statins, and the endogenous lipoxins. In the presence of aspirin, stable analogues of lipoxin (i.e. epi-lipoxins) are formed in a trans-cellular process. Lipoxin inhibited the signalling capacity of β2 integrins mediated by intermediary chemoattractants, as well as the signal transduction induced by end-target chemoattractants. Moreover, the signalling capacity of β2 integrins in neutrophils from patients suffering from coronary artery disease (CAD) was impaired. Arachidonic acid, the precursor for both pro- and anti-inflammatory eicosanoid, induced an increase in the β2 integrin activity (both affinity and avidity), but had no effect on the signal transduction.

    In conclusion, different “roles” were observed for end-target and intermediary chemoattractants in the regulation of β2 integrins. The inhibitory effects of the anti-inflammatory lipoxins support earlier studies suggesting that these agents function as “stop signals” in inflammation. This is also confirmed by our findings in CAD patients, who have elevated levels of epi-lipoxins due to aspirin treatment. Moreover, Pyk2 was identified as a possible target for the inhibitory effect of anti-inflammatory drugs.

    Delarbeid
    1. Differential inside-out activation of β2 integrins by leukotriene B4 and fMLP in human neutrophils
    Åpne denne publikasjonen i ny fane eller vindu >>Differential inside-out activation of β2 integrins by leukotriene B4 and fMLP in human neutrophils
    Vise andre…
    2004 (engelsk)Inngår i: Experimental Cell Research, ISSN 0014-4827, E-ISSN 1090-2422, Vol. 300, nr 2, s. 308-319Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    We have investigated how LTB4, an endogenous chemoattractant encountered early in the inflammatory process, and fMLP, a bacteria-derived chemotactic peptide emanating from the site of infection, mediate inside-out regulation of the β2-integrin. The role of the two chemoattractants on β2-integrin avidity was investigated by measuring their effect on β2-integrin clustering and surface mobility, whereas their effect on β2-integrin affinity was measured by the expression of a high affinity epitope, a ligand-binding domain on β2-integrins, and by integrin binding to s-ICAM. We find that the two chemoattractants modulate the β2-integrin differently. LTB4 induces an increase in integrin clustering and surface mobility, but only a modest increase in integrin affinity. fMLP evokes a large increase in β2-integrin affinity as well as in clustering and mobility. Lipoxin, which acts as a stop signal for the functions mediated by pro-inflammatory agents, was used as a tool for further examining the inside-out mechanisms. While LTB4-induced integrin clustering and mobility were inhibited by lipoxin, only a minor inhibition of fMLP-induced β2-integrin avidity and no inhibition of integrin affinity were detected. The different modes of the inside-out regulation of β2-integrins suggest that distinct mechanisms are involved in the β2-integrin modulation induced by various chemoattractants.

    Emneord
    β2-Integrins, Cell adhesion, Chemotactic factors, Eicosanoids, Inflammation, Leukotriene B4, Lipoxins, Human Neutrophils, Signal transduction
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-14629 (URN)10.1016/j.yexcr.2004.07.015 (DOI)
    Tilgjengelig fra: 2007-09-13 Laget: 2007-09-13 Sist oppdatert: 2017-12-13bibliografisk kontrollert
    2. LIpoxin A4 inhibits the fMet-Leu-Phe-induced, but not the β2 integrin-induced activation of the non-receptor tyrosine kinase Pyk2 in Human Leukemia 60 cells
    Åpne denne publikasjonen i ny fane eller vindu >>LIpoxin A4 inhibits the fMet-Leu-Phe-induced, but not the β2 integrin-induced activation of the non-receptor tyrosine kinase Pyk2 in Human Leukemia 60 cells
    Manuskript (Annet vitenskapelig)
    Identifikatorer
    urn:nbn:se:liu:diva-14630 (URN)
    Tilgjengelig fra: 2007-09-13 Laget: 2007-09-13 Sist oppdatert: 2010-01-13
    3. Inside-out regulated β2-integrin-induced release of arachidonic acid in Human Leukemia 60 cells
    Åpne denne publikasjonen i ny fane eller vindu >>Inside-out regulated β2-integrin-induced release of arachidonic acid in Human Leukemia 60 cells
    Manuskript (Annet vitenskapelig)
    Identifikatorer
    urn:nbn:se:liu:diva-14631 (URN)
    Tilgjengelig fra: 2007-09-13 Laget: 2007-09-13 Sist oppdatert: 2010-01-13
    4. Inactivation of Cdc42 is nessecary for depolymerization of phagosomal F-actin and subsequent phagosomal maturation
    Åpne denne publikasjonen i ny fane eller vindu >>Inactivation of Cdc42 is nessecary for depolymerization of phagosomal F-actin and subsequent phagosomal maturation
    Vise andre…
    2007 (engelsk)Inngår i: Journal of Immunology, ISSN 0022-1767, Vol. 178, nr 11, s. 7357-7365Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Phagocytosis is a complex process involving the activation of various signaling pathways, such as the Rho GTPases, and the subsequent reorganization of the actin cytoskeleton. In neutrophils, Rac and Cdc42 are activated during phagocytosis but less is known about the involvement of these GTPases during the different stages of the phagocytic process. The aim of this study was to elucidate the role of Cdc42 in phagocytosis and the subsequent phagosomal maturation. Using a TAT-based protein transduction technique, we introduced dominant negative and constitutively active forms of Cdc42 into neutrophil-like HL60 (human leukemia) cells that were allowed to phagocytose IgG-opsonized yeast particles. Staining of cellular F-actin in cells transduced with constitutively active Cdc42 revealed that the activation of Cdc42 induced sustained accumulation of periphagosomal actin. Moreover, the fusion of azurophilic granules with the phagosomal membrane was prevented by the accumulated F-actin. In contrast, introducing dominant negative Cdc42 impaired the translocation per se of azurophilic granules to the periphagosomal area. These results show that efficient phagosomal maturation and the subsequent eradication of ingested microbes in human neutrophils is dependent on a strictly regulated Cdc42. To induce granule translocation, Cdc42 must be in its active state but has to be inactivated to allow depolymerization of the F-actin cage around the phagosome, a process essential for phagolysosome formation.

    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-14632 (URN)
    Tilgjengelig fra: 2007-09-13 Laget: 2007-09-13
    5. Neutrophil activation status in stable coronary artery disease.
    Åpne denne publikasjonen i ny fane eller vindu >>Neutrophil activation status in stable coronary artery disease.
    Vise andre…
    2007 (engelsk)Inngår i: PLoS ONE, ISSN 1932-6203, Vol. 2, nr 10, s. e1056-Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Background: During the last years, neutrophils have emerged as important players in atherogenesis. They are highly activated in peripheral blood of patients with unstable angina. Moreover, a primed state of circulating neutrophils has been proposed in patients with stable angina. Our aim was to investigate the neutrophil activation status in patients with stable coronary artery disease (CAD) at conventional drug treatment.

    Methodology and principal findings: Thirty patients with stable CAD and 30 healthy controls were included using a paired design. The neutrophil expression of CD18 and high-affinity state of CD11b was analysed by flow cytometry before and after stimulation with chemoattractants. Also, the production of reactive oxygen species (ROS) was determined by chemiluminescence. During basal conditions, the neutrophil expression of CD18 or high-affinity state of CD11b did not differ between patients and controls. Chemoattractants (Interleukin-8 and Leukotriene B(4)) did not increase either the expression or the amount of high-affinity CD11b/CD18-integrins in CAD patients compared to controls, and had no effect on the production of ROS. On the other hand, the ROS production in response to C3bi-opsonised yeast particles and the neutrophils' inherent capacity to produce ROS were both significantly decreased in patients.

    Conclusion/Significance: We could not find any evidence that neutrophils in patients with stable CAD were primed, i.e. more prone to activation, compared to cells from healthy controls. According to our data, the circulating neutrophils in CAD patients rather showed an impaired activation status. It remains to be elucidated whether the neutrophil dysfunction in CAD is mainly a marker of chronic disease, an atherogenic factor or a consequence of the drug treatment.

    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-17246 (URN)10.1371/journal.pone.0001056 (DOI)17957240 (PubMedID)
    Tilgjengelig fra: 2009-03-12 Laget: 2009-03-12 Sist oppdatert: 2010-01-14
    Fulltekst (pdf)
    FULLTEXT01
    Download (pdf)
    COVER01
  • 267.
    Brose, Ulrich
    et al.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Blanchard, Julia L.
    Institute for Marine and Antarctic Studies and Centre for Marine Socioecology, University of Tasmania, 20 Castray Esplanade, Battery Point TAS 7004 Australia.
    Eklöf, Anna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Galiana, Nuria
    Ecological Networks and Global Change Group, Experimental Ecology Station, Centre National de la Recherche Scientifique, 09200, Moulis, France.
    Hartvig, Martin
    Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark, University of Copenhagen, DK-2100, Copenhagen, Denmark 7 National Institute of Aquatic Resources, Technical University of Denmark, DK-2920, Charlottenlund, Denmark 8 Systemic Conservation Biology Group, J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August University of Göttingen, 37073, Göttingen, Germany.
    Hirt, Myriam R.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Kalinkat, Gregor
    Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, 12587, Berlin, Germany 10 Department of Fish Ecology and Evolution, Eawag, 6047, Kastanienbaum, Switzerland.
    Nordström, MArie C.
    Environmental and Marine Biology, Åbo Akademi University, FI-20520, Åbo, Finland.
    O'Gorman, Eoin J.
    Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.
    Rall, Björn C.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Schneider, Florian D.
    Institut des Sciences de l’Evolution, Universit´e Montpellier, CNRS, IRD, EPHE, CC065, 34095, Montpellier Cedex 05, France.
    Thébault, Elisa
    Institute of Ecology and Environmental Sciences - Paris, UMR 7618 (UPMC, CNRS, IRD, INRA, UPEC, Paris Diderot), Universit´e Pierre et Marie Curie, 75005, Paris, France.
    Jacob, Ute
    Department of Biology, Institute for Hydrobiology and Fisheries Science, Center for Earth System Research and Sustainability (CEN), KlimaCampus, University of Hamburg, 22767, Hamburg, Germany.
    Predicting the consequences of species lossusing size-structured biodiversity approaches2017Inngår i: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 92, nr 2, s. 684-697Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Understanding the consequences of species loss in complex ecological communities is one of the great challenges in current biodiversity research. For a long time, this topic has been addressed by traditional biodiversity experiments. Most of these approaches treat species as trait-free, taxonomic units characterizing communities only by species number without accounting for species traits. However, extinctions do not occur at random as there is a clear correlation between extinction risk and species traits. In this review, we assume that large species will be most threatened by extinction and use novel allometric and size-spectrum concepts that include body mass as a primary species trait at the levels of populations and individuals, respectively, to re-assess three classic debates on the relationships between biodiversity and (i) food-web structural complexity, (ii) community dynamic stability, and (iii) ecosystem functioning. Contrasting current expectations, size-structured approaches suggest that the loss of large species, that typically exploit most resource species, may lead to future food webs that are less interwoven and more structured by chains of interactions and compartments. The disruption of natural body-mass distributions maintaining food-web stability may trigger avalanches of secondary extinctions and strong trophic cascades with expected knock-on effects on the functionality of the ecosystems. Therefore, we argue that it is crucial to take into account body size as a species trait when analysing the consequences of biodiversity loss for natural ecosystems. Applying size-structured approaches provides an integrative ecological concept that enables a better understanding of each species' unique role across communities and the causes and consequences of biodiversity loss.

  • 268.
    Brose, Ulrich
    et al.
    Technical University of Darmstadt, Germany.
    Pavao-Zuckerman, Mitchell
    University of Arizona, Tucson, Arizona, USA.
    Eklöf, Anna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska högskolan.
    Bengtsson, Janne
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Berg, Matty P.
    Vrije Universiteit Amsterdam, The Netherlands.
    Cousins, Steven H.
    Cranfield University, United Kingdom.
    Mulder, Christian
    National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
    Verhoef, Herman A.
    Vrije Universiteit Amsterdam, The Netherlands.
    Wolters, Volkmar
    Justus-Liebig-University, Giessen, Germany.
    Spatial aspects of food webs2005Inngår i: Dynamic Food Webs: Multispecies Assemblages, Ecosystem Development and Environmental Change / [ed] P.C. deRuiter, V. Wolters & J.C. Moore, London, UK: Elsevier, 2005, Vol. 3, s. 463-469Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Aspects of spatial scale have until recently been largely ignored in empirical and theoretical food web studies (e.g., Cohen & Briand 1984, Martinez 1992, but see Bengtsson et al. 2002, Bengtsson & Berg, this book). Most ecologists tend to conceptualize and represent food webs as static representations of communities, depicting a community assemblage as sampled at a particular point in time, or highly aggregated trophic group composites over broader scales of time and space (Polis et al. 1996). Moreover, most researchers depict potential food webs, which contain all species sampled and all potential trophic links based on literature reviews, several sampling events, or laboratory feeding trials. In reality, however, not all these potential feeding links are realized as not all species co-occur, and not all samples in space or time can contain all species (Schoenly & Cohen 1991), hence, yielding a variance of food web architecture in space (Brose et al. 2004). In recent years, food web ecologists have recognized that food webs are open systems – that are influence by processes in adjacent systems – and spatially heterogeneous (Polis et al. 1996). This influence of adjacent systems can be bottom-up, due to allochthonous inputs of resources (Polis & Strong 1996, Huxel & McCann 1998, Mulder & De Zwart 2003), or top-down due to the regular or irregular presence of top predators (e.g., Post et al. 2000, Scheu 2001). However, without a clear understanding of the size of a system and a definition of its boundaries it is not possible to judge if flows are internal or driven by adjacent systems. Similarly, the importance of allochthony is only assessable when the balance of inputs and outputs are known relative to the scale and throughputs within the system itself. At the largest scale of the food web – the home range of a predator such as wolf, lion, shark or eagle of roughly 50 km2 to 300 km2 –the balance of inputs and outputs caused by wind and movement of water may be small compared to the total trophic flows within the home range of the large predator (Cousins 1990). Acknowledging these issues of space, Polis et al (1996) argued that progress toward the next phase of food web studies would require addressing spatial and temporal processes. Here, we present a conceptual framework with some nuclei about the role of space in food web ecology. Although we primarily address spatial aspects, this framework is linked to a more general concept of spatio-temporal scales of ecological research.

  • 269.
    Brunberg, Emma I
    et al.
    NORSØK – Norwegian Centre for Organic Agriculture, Tingvoll, Norway; NIBIO – Norwegian Institute for Bioeconomy Research, Tingvoll, Norway.
    Rodenburg, T Bas
    Behavioural Ecology Group, Wageningen University, Wageningen, Netherlands.
    Rydhmer, Lotta
    Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Kjaer, Joergen B
    Federal Research Institute for Animal Health, Friedrich-Loeffler-Institut, Celle, Germany,.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Keeling, Linda J
    Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Omnivores Going Astray: A Review and New Synthesis of Abnormal Behavior in Pigs and Laying Hens2016Inngår i: Frontiers in veterinary science, ISSN 2297-1769, Vol. 3, s. 1-15, artikkel-id 57Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pigs and poultry are by far the most omnivorous of the domesticated farm animals and it is in their nature to be highly explorative. In the barren production environments, this motivation to explore can be expressed as abnormal oral manipulation directed toward pen mates. Tail biting (TB) in pigs and feather pecking (FP) in laying hens are examples of unwanted behaviors that are detrimental to the welfare of the animals. The aim of this review is to draw these two seemingly similar abnormalities together in a common framework, in order to seek underlying mechanisms and principles. Both TB and FP are affected by the physical and social environment, but not all individuals in a group express these behaviors and individual genetic and neurobiological characteristics play an important role. By synthesizing what is known about environmental and individual influences, we suggest a novel possible mechanism, common for pigs and poultry, involving the brain-gut-microbiota axis.

    Fulltekst (pdf)
    fulltext
  • 270.
    Brusman, Anna-Lena
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Etiska aspekter av preimplantatorisk genetisk diagnostik och genterapi2007Independent thesis Advanced level (degree of Magister), 20 poäng / 30 hpOppgave
    Abstract [en]

    The research in the field of biotechnology is rapidly developing all over the world. Modern biotechnology offers unique opportunities, simultaneously as it gives rise to a number of ethical issues. Preimplantation genetic diagnosis (PGD), PGD/HLA (Human Leucocyte Antigen) and germline gene therapy (GLGT) are controversial techniques. PGD gives a possibility to identify a genetic disease prior to the embryo’s implantation in the uterus. PGD/HLA involves selecting an embryo with genes coding for a specific tissue type, so that the child to be born can act as a donor to an existing sibling who requires a stem cell transplant. GLGT seeks to eliminate or change “bad” genes.

    The purpose of this study is to investigate student’s ethical attitude concerning PGD, PGD/HLA and GLGT.

    The empirical study was based on focus group discussions. Four group interviews were made, with 15 participants in all. The students are taking courses in biology or religion.

    The result from the interviews shows that the ethical issues are difficult to have a definite opinion in, because there are possibilities and risks involved in all these techniques, according to the students. A central part of the discussion was devoted to human dignity and the moral status of the embryo. They also see risks such as bioterrorism, designing the perfect humans, economic interests, medical risks, among many other risks.

    Fulltekst (pdf)
    FULLTEXT01
  • 271.
    Bröms Axelsson, Emilia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Do we protect the right forests? – A case study of representativeness of protected forests in Östergötland, Sweden, and identification of tracts of value.2015Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Protected forests need to be a representative selection of the natural proportion of forest types, including distribution of productivity levels, age classes and nature types This is important for the possibility to preserve biodiversity. In addition, the protected areas has to be of sufficient size and not isolated from each other, to function as effective biodiversity preservers. The question is, how does it look in reality? The objective with this study was to get an overall picture of the current forest protection situation in Östergötland, Sweden, and how it has changed the last 60 years. Are all ecologically relevant forest habitat types represented in appropriate proportions in protected forests? To evaluate where the protected areas are located in relation to each other, a connectivity index was calculated for each patch of protected area. Together with a value for size, a value index was created and applied to all protected areas, and it turns out that the protected areas of Östergötland is not totally representative when it comes to nature types, age classes and levels of productivity.For example, there is an underrepresentation of both pine and spruce forests on high-productivity soils. However, areas with higher productivity levels have been protected over time. The age distribution seems to be skewed towards older forests in protected areas. There are some underrepresented nature types, as well as overrepresented ones in nature reserves, a small overrepresentation of unproductive impediments, and only spruce and mixed forests seems well connected in the landscape. The greatest differences in protected and unprotected forests is the productivity level, were focus should be on protecting higher productivity areas in order to succeed in preserving the biodiversity of forests as intended.

    Fulltekst (pdf)
    Do we protect the right forests - Emilia Bröms Axelsson
  • 272.
    Bröms Axelsson, Emilia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Kloridutlakning från flygaska: möjligheten till en lokal hantering2014Independent thesis Basic level (degree of Bachelor), 180 hpOppgave
    Abstract [en]

    In Sweden, there are limits to how much leachable substances waste must contain in order to be deposited as hazardous waste. Fly ash from waste incineration often end up over the limit, mainly due to the chloride content. Fly ash is therefore often deposited abroad. The purpose of this study was to investigate the possibility to handle fly ash locally. To clarify how the law is applied, environmental reports and permit documents from ten waste sites with permission to deposit fly ash were studied. In addition, a literature study was made to review the state of knowledge regarding the treatments of fly ash. The treatment methods are numerous, but are at different levels of commerciality. Among the treatments available there are both physical, chemical, biological, electrical and thermal variants. Many of the treatments (except for carbonation and microbial bioleaching) results in chloride levels below the limits. Several are however unrealistically expensive or generate wastewater with high levels of chloride that would need further treatment. Three plants out of the ten holding permits to deposit fly ash, have exemptions from the limit for chlorides. It's however difficult to see a common reasoning for allowing exemptions. In several cases there are sensitive receiving waters downstream from the landfill. One reason to be dispensed despite this sensitivity, may be the guidance that EPA issued. It is not formulated any specific concerns relating to chlorides. One handles therefore often high levels of chloride in the leachate as a dilution problem, not a leaching problem.

    Fulltekst (pdf)
    fulltext
  • 273.
    Brüsin, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Influence of landscape scale and habitat distribution on individual bat species and bat species richness2013Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Habitat fragmentation is one of the most important factors affecting species extinction and biodiversity loss, Species habitat response expects to differ with habitat feature at different spatial scales and this study was to identify how bat diversity and individual bat species respond to different habitat amounts. The local bat species richness was observed in 156 different locations in Östergötland and the proportion of different habitats were calculated for circular areas with diameters ranging from 400 m. to 12 km. from each location. Although we found that the individual bat species responded differently to the amount of each habitat at different spatial scales, the bat species richness showed a decreasing response with increasing spatial scale. The strongest response of bat species richness to habitat characteristics was at a scale of 939 m.

    Fulltekst (pdf)
    fulltext
  • 274.
    Bunkoczi, Gabor
    et al.
    University of Cambridge, England.
    Wallner, Björn
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Bioinformatik. Linköpings universitet, Tekniska högskolan.
    Read, Randy J.
    University of Cambridge, England.
    Local Error Estimates Dramatically Improve the Utility of Homology Models for Solving Crystal Structures by Molecular Replacement2015Inngår i: Structure, ISSN 0969-2126, E-ISSN 1878-4186, Vol. 23, nr 2, s. 397-406Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Predicted structures submitted for CASP10 have been evaluated as molecular replacement models against the corresponding sets of structure factor amplitudes. It has been found that the log- likelihood gain score computed for each prediction correlates well with common structure quality indicators but is more sensitive when the accuracy of the models is high. In addition, it was observed that using coordinate error estimates submitted by predictors to weight the model can improve its utility in molecular replacement dramatically, and several groups have been identified who reliably provide accurate error estimates that could be used to extend the application of molecular replacement for low-homology cases.

    Fulltekst (pdf)
    fulltext
  • 275.
    Bunnfors, Kalle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska fakulteten.
    Synthesis and electrochemical characterisation of processable polypyrrole boronic acid derivatives for carbohydrate binding2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Conducting polymers have been widely explored for many different purposes including sensing. In thisthesis the conducive properties of pyrrole and the carbohydrate binding properties of boronic acid iscombined to make a reagent-free detector for carbohydrates. The polymer is manufactured in form ofparticles in the μm scale to create a porous film which has a high surface to volume ratio.The material was characterised and the binding properties were evaluated for galactose and glucose.Proof of binding was found via both electrochemical methods and QCM-D. A correlation between R2 value and concentration of substrate was found which enables measurement of concentration of carbohydratesin unknown samples.

    Fulltekst (pdf)
    fulltext
  • 276.
    Bunnfors, Kalle
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Abrikossova, Natalia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Kilpijarvi, Joni
    Not Found:Linkoping Univ, Dept Phys Chem and Biol, Div Mol Surface Phys and Nanosci, SE-58183 Linkoping, Sweden; Univ Oulu, Finland.
    Eriksson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Juuti, Jari
    Univ Oulu, Finland.
    Halonen, Niina
    Univ Oulu, Finland.
    Brommesson, Caroline
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Lloyd Spetz, Anita
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensor- och aktuatorsystem. Linköpings universitet, Tekniska fakulteten.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Nanoparticle activated neutrophils-on-a-chip: A label-free capacitive sensor to monitor cells at work2020Inngår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, SENSORS AND ACTUATORS B-CHEMICAL, Vol. 313, artikkel-id 128020Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Neutrophil granulocytes are the most abundant white blood cells in mammals and vital components of the immune system. They are involved in the early phase of inflammation and in generation of reactive oxygen species. These rapid cell-signaling communicative processes are performed in the time frame of minutes. In this work, the activity and the response of neutrophil granulocytes are monitored when triggered by cerium-oxide based nanoparticles, using capacitive sensors based on Lab-on-a-chip technology. The chip is designed to monitor activation processes of cells during nanoparticle exposure, which is for the first time recorded on-line as alteration of the capacitance. The complementary metal oxide semiconductor engineering chip design is combined with low temperature co-fired ceramic, LTCC, packaging technology. The method is label free and gently measures cells on top of an insulating surface in a weak electromagnetic field, as compared to commonly used four-point probes and impedance spectroscopy electric measurements where electrodes are in direct contact with the cells. In summary, this label free method is used to measure oxidative stress of neutrophil granulocytes in real time, minute by minute and visualize the difference in moderate and high cellular workload during exposure of external triggers. It clearly shows the capability of this method to detect cell response during exposure of external triggers. In this way, an informationally dense non-invasive method is obtained, to monitor cells at work.

  • 277.
    Burek, C. J.
    et al.
    University of Münster, Germany.
    Roth, J.
    University of Münster, Germany.
    Koch, H. G.
    University of Münster, Germany.
    Harzer, K.
    University of Tübingen, Germany.
    Los, Marek Jan
    Department of Immunology and Cell Biology, University of Münster, Germany.
    Schulze-Osthoff, Klaus
    University of Münster, Germany .
    The role of ceramide in receptor- and stress-induced apoptosis studied in acidic ceramidase-deficient Farber disease cells2001Inngår i: Oncogene, ISSN 0950-9232, E-ISSN 1476-5594, Vol. 20, nr 45, s. 6493-6502Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The activation of sphingomyelinases leading to the generation of ceramide has been implicated in various apoptotic pathways. However, the role of ceramide as an essential death mediator remains highly controversial. In the present study, we investigated the functional relevance of ceramide in a genetic model by using primary cells from a Farber disease patient. These cells accumulate ceramide as the result of an inherited deficiency of acidic ceramidase. We demonstrate that Farber disease lymphocytes and fibroblasts underwent apoptosis induced by various stress stimuli, including staurosporine, anticancer drugs and gamma -irradiation, equally as normal control cells. In addition, caspase activation by these proapoptotic agents occurred rather similarly in Farber disease and control fibroblasts. Interestingly, Farber disease lymphoid cells underwent apoptosis induced by the CD95 death receptor more rapidly than control cells. Our data therefore suggest that ceramide does not play an essential role as a second messenger in stress-induced apoptosis. However, in accordance with a role in lipid-rich microdomains, ceramide by altering membrane composition may function as an amplifier in CD95-mediated apoptosis.

    Fulltekst (pdf)
    fulltext
  • 278.
    Burek, M.
    et al.
    Department of Immunology and Cell Biology, University of Münster, Münster, Germany.
    Maddika, Subbareddy
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Department of Biochemistry and Medical Genetics,University of Manitoba, Winnipeg, Canada .
    Burek, C. J.
    Department of Immunology and Cell Biology, University of Münster, Münster, Germany.
    Daniel, P. T.
    Department of Hematology, Oncology and Tumor Immunology, Charité, Berlin, Germany.
    Schulze-Osthoff, Klaus
    nstitute of Molecular Medicine, University of Düsseldorf, Düsseldorf, Germany .
    Los, Marek Jan
    Manitoba Institute of Cell Biology, Cancer Care Manitoba; Manitoba Institute of Child Health; Department of Biochemistry and Medical Genetics; Department of Human Anatomy and Cell Science, University Manitoba, Winnipeg, Canada, .
    Apoptin-induced cell death is modulated by Bcl-2 family members and is Apaf-1dependent2006Inngår i: Oncogene, ISSN 0950-9232, E-ISSN 1476-5594, Vol. 25, nr 15, s. 2213-2222Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Apoptin, a chicken anemia virus-derived protein, selectively induces apoptosis in transformed but not in normal cells, thus making it a promising candidate as a novel anticancer therapeutic. The mechanism of apoptin-induced apoptosis is largely unknown. Here, we report that contrary to previous assumptions, Bcl-2 and Bcl-x(L) inhibit apoptin-induced cell death in several tumor cell lines. In contrast, deficiency of Bax conferred resistance, whereas Bax expression sensitized cells to apoptin-induced death. Cell death induction by apoptin was associated with cytochrome c release from mitochondria as well as with caspase-3 and -7 activation. Benzyloxy-carbonyl-Val-Ala-Asp-fluoromethyl ketone, a broad spectrum caspase inhibitor, was highly protective against apoptin-induced cell death. Apoptosis induced by apoptin required Apaf-1, as immortalized Apaf-1-deficient fibroblasts as well as tumor cells devoid of Apaf-1 were strongly protected. Thus, our data indicate that apoptin-induced apoptosis is not only Bcl-2- and caspase dependent, but also engages an Apaf-1 apoptosome-mediated mitochondrial death pathway.

    Fulltekst (pdf)
    fulltext
  • 279.
    Burgevin, Lorraine
    et al.
    Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Friberg, Urban
    Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Maklakov, Alexei A.
    Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Intersexual correlation for same-sex sexual behaviour in an insect2013Inngår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 85, nr 4, s. 759-762Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Same-sex sexual behaviour is widespread across taxa and is particularly common in insects, in which up to 50% of copulation attempts by males are directed towards other males in some species. Research effort has focused on male-male same-sex behaviour and the prevailing theory is that benefits of high mating rate combined with poor sex discrimination explain the high incidence of male-male mounting. However, the evolution of female-female mounting is more enigmatic, since females typically do not mount males in order to mate. Using a full-sib design, we found an intersexual correlation for same-sex mounting in the beetle Callosobruchus maculatus. Variation in male-male mounting across families explained over 20% of variation in female-female mounting. Moreover, we found no evidence that same-sex behaviour was related to general activity level in either sex or carried a fitness cost to females. Taken together, our results suggest that female-female mounting is a relatively low-cost behaviour that may be maintained in the population via selection on males.

  • 280.
    Burman, Joseph
    et al.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden/Ecology Research Group, Canterbury Christ Church University, Canterbury, Kent, CT1 1QU, England, UK .
    Westerberg, Lars
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Ostrow, Suzanne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Ryrholm, Nils
    University of Gävle, 801 76 Ga¨vle, Sweden.
    Bergman, Karl-Olof
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Winde, Inis
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences,Alnarp, Sweden, Department of Biology, Lund University, So¨lvegatan 37, 223 62 Lund, Sweden.
    Nyabuga, Franklin N.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden, Department of Biology, Lund University, So¨lvegatan 37, 223 62 Lund, Sweden.
    Larsson, Mattias C.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden.
    Milberg, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Revealing hidden species distribution with pheromones: the caseof Synanthedon vespiformis (Lepidoptera: Sesiidae) in Sweden2016Inngår i: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 20, nr 1, s. 11-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Synanthedon vespiformis L. (Lepidoptera:Sesiidae) is considered a rare insect in Sweden, discoveredin 1860, with only a few observations recorded until a sexpheromone attractant became available recently. This studydetails a national survey conducted using pheromones as asampling method for this species. Through pheromonetrapping we captured 439 specimens in Southern Sweden at77 sites, almost tripling the number of previously reportedrecords for this species. The results suggest that S. vespiformisis truly a rare species with a genuinely scattereddistribution, but can be locally abundant. Habitat analyseswere conducted in order to test the relationship betweenhabitat quality and the number of individuals caught. InSweden, S. vespiformis is thought to be associated with oakhosts, but our attempts to predict its occurrence by theabundance of oaks yielded no significant relationships. Wetherefore suggest that sampling bias and limited knowledgeon distribution may have led to the assumption that thisspecies is primarily reliant on oaks in the northern part ofits range, whereas it may in fact be polyphagous, similar toS. vespiformis found as an agricultural pest in Central andSouthern Europe. We conclude that pheromones canmassively enhance sampling potential for this and otherrare lepidopteran species. Large-scale pheromone-basedsurveys provide a snapshot of true presences and absencesacross a considerable part of a species national distributionrange, and thus for the first time provide a viable means ofsystematically assessing changes in distribution over timewith high spatiotemporal resolution.

  • 281.
    Bzhalava, David
    et al.
    Karolinska Institutet and Karolinska University Hospital, Stockholm.
    Ekström, Johanna
    Lund University, Malmö.
    Lysholm, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Bioinformatik. Linköpings universitet, Tekniska högskolan.
    Hultin, Emilie
    Karolinska Institutet and Karolinska University Hospital, Stockholm.
    Faust, Helena
    Lund University, Malmö.
    Persson, Bengt
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Bioinformatik. Linköpings universitet, Tekniska högskolan.
    Lehtinen, Matti
    National Institute for Health and Welfare, Oulu, Finland.
    de Villiers, Ethel-Michele
    Deutsches Krebsforschungszentrum, Heidelberg, Germany.
    Dillner, Joakim
    Karolinska Institutet and Karolinska University Hospital, Stockholm.
    Phylogenetically diverse TT virus viremia among pregnant women2012Inngår i: Virology, ISSN 0042-6822, E-ISSN 1096-0341, Vol. 432, nr 2, s. 427-434Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Infections during pregnancy have been suggested to be involved in childhood leukemias. We used high-throughput sequencing to describe the viruses most readily detectable in serum samples of pregnantwomen. Serum DNA of 112 mothers to leukemic children was amplified using whole genome amplification. Sequencing identified one TTvirus (TTV) isolate belonging to a known type and two putatively new TTVs. For 22 mothers, we also performed TTV amplification by general primer PCR before sequencing. This detected 39 TTVs, two of which were identical to the TTVs found after whole genome amplification.

    Altogether, we found 40 TTV isolates, 29 of which were putatively new types (similarities ranging from 89% to 69%). In conclusion, high throughput sequencing is useful to describe the known or unknown viruses that are present in serum samples of pregnantwomen.

  • 282.
    Bäcklund, Fredrik
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Elfwing, Anders
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ajjan, Fatimá Nadia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Babenko, Viktoria
    Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Poland.
    Dzwolak, Wojciech
    Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Poland.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    PEDOT-S coated protein fibril microhelicesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    We show here the preparation and characterization of micrometer sized conductive helices. We utilize protein fibrils as structural templates to create chiral helices with either right or left handed helicity. The helices are coated with the conductive polymer alkoxysulfonate poly(ethylenedioxythiophene) (PEDOT-S) to create micrometer sized conductive helices. The coating acts as a stabilizer for the template structure, facilitates the preparation of solid state films and shows significant conductivity. The helices have been investigated using Circular Dichroism (CD) and scanning electron microscopy (SEM) and the conductivity have been measured for solid state films.

  • 283.
    Bäcklund, Fredrik
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Development and Application of Methodology for Rapid Screening of Potential Amyloid Probes2014Inngår i: ACS COMBINATORIAL SCIENCE, ISSN 2156-8952, Vol. 16, nr 12, s. 721-729Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein, we demonstrate that it is possible to rapidly screen hydrophobic fluorescent aromatic molecules with regards to their properties as amyloid probes. By grinding the hydrophobic molecule with the amyloidogenic protein insulin, we obtained a water-soluble composite material. When this material is dissolved and exposed to conditions promoting amyloid formation, the protein aggregates into amyloid fibrils incorporating the hydrophobic molecule. As a result, changes in the fluorescence spectra of the hydrophobic molecule can be correlated to the formation of amyloid fibrils, and the suitability of the hydrophobic molecular skeleton as an amyloid probe can thus be assessed. As a result, we discovered two new amyloid probes, of which one is the well-known laser dye DCM. The grinding method can also be used for rapid preparation of novel composite materials between dyes and proteins, which can be used in materials science applications such as organic electronics and photonics.

  • 284.
    Bäcklund, Fredrik
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wigenius, Jens
    Chalmers, Sweden.
    Westerlund, Fredrik
    Chalmers, Sweden .
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Amyloid fibrils as dispersing agents for oligothiophenes: control of photophysical properties through nanoscale templating and flow induced fibril alignment2014Inngår i: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 2, nr 37, s. 7811-7822Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein we report that protein fibrils formed from aggregated proteins, so called amyloid fibrils, serve as an excellent dispersing agent for hydrophobic oligothiophenes such as alpha-sexithiophene (6T). Furthermore, the protein fibrils are capable of orienting 6T along the fibril long axis, as demonstrated by flow-aligned linear dichroism spectroscopy and polarized fluorescence microscopy. The materials are prepared by solid state mixing of 6T with a protein capable of self-assembly. This results in a water soluble composite material that upon heating in aqueous acid undergoes self-assembly into protein fibrils non-covalently functionalized with 6T, with a typical diameter of 5-10 nm and lengths in the micrometre range. The resulting aqueous fibril dispersions are a readily available source of oligothiophenes that can be processed from aqueous solvent, and we demonstrate the fabrication of macroscopic structures consisting of aligned 6T functionalized protein fibrils. Due to the fibril induced ordering of 6T these structures exhibit polarized light emission.

  • 285. Bestill onlineKjøp publikasjonen >>
    Bélteky, Johan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Chicken domestication: Effects of tameness on brain gene expression and DNA methylation2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Domestication greatly increases phenotypic variation in a short time span, with selection for a single phenotype and a plethora of associated phenotypic changes as an outcome of the process. The domestication process influences the underlying genomic architecture of a species, and the success and speed of the process is likely influenced by it. The main aims of my thesis was to study how domestication affects the brain of chickens: specifically changes in morphology, gene expression, and DNA methylation. Differences in gene expression and DNA methylation between White Leghorn and Red Junglefowl chickens were mapped, and inheritance of these patterns were quantified, indicating a faithful transmission of breed-specific epigenetic markers. Selection on the behavioral trait fearfulness, generated high and low fearful lines of Red Junglefowl. Both the parental population and the fifth selected generation were used for the analyses in this thesis. One experiment studied morphological changes in the brain and other vital organs, and found that relative total brain size increased in high fearful birds, as a consequence of an increase in cerebral hemisphere size in high fearful birds and not in low fearful birds. Also, the relative heart, liver, spleen and testis size increased in high fearful birds, indicating correlated morphological changes with selection for fearfulness. Two additional experiments examined differential gene expression in the hypothalamus and the anterior cerebral hemisphere. The hypothalamus differed in expression of genes with reproductive and immunological functions, whilst the cerebral hemisphere differed in expression of genes related to social behaviors and neurological functions especially those upregulated in low fearful birds.  These results indicate the occurrence of tissue- and species-specific changes in gene expression as overlap with other domestication events were nearly nonexistent. A fourth experiment sought to associate the change in fear levels and gene expression differences with DNA methylation. Chromosomal regions with differential DNA methylation between high and low fearful birds were identified, and genes in these regions had annotated functions relevant to phenotypic differences between the selection lines. This thesis is the first to study the genetic alterations of domestication using the wild ancestor of an already domesticated species to repeat the domestication process selecting against fear of humans. The findings corroborate results from previous comparisons of wild and domestic animals, and further support the theory that rigorous selection for a behavioral trait can cause a cascade of genetic and epigenetic changes facilitating the domestication of a population.

    Delarbeid
    1. Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Åpne denne publikasjonen i ny fane eller vindu >>Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Vise andre…
    2012 (engelsk)Inngår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 13, nr 59Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Variations in gene expression, mediated by epigenetic mechanisms, may cause broad phenotypic effects in animals. However, it has been debated to what extent expression variation and epigenetic modifications, such as patterns of DNA methylation, are transferred across generations, and therefore it is uncertain what role epigenetic variation may play in adaptation. Here, we show that in Red Junglefowl, ancestor of domestic chickens, gene expression and methylation profiles in thalamus/hypothalamus differ substantially from that of a domesticated egg laying breed. Expression as well as methylation differences are largely maintained in the offspring, demonstrating reliable inheritance of epigenetic variation. Some of the inherited methylation differences are tissue-specific, and the differential methylation at specific loci are little changed after eight generations of intercrossing between Red Junglefowl and domesticated laying hens. There was an over-representation of differentially expressed and methylated genes in selective sweep regions associated with chicken domestication. Hence, our results show that epigenetic variation is inherited in chickens, and we suggest that selection of favourable epigenomes, either by selection of genotypes affecting epigenetic states, or by selection of methylation states which are inherited independently of sequence differences, may have been an important aspect of chicken domestication.

    sted, utgiver, år, opplag, sider
    BioMed Central, 2012
    Emneord
    Domestication, gene expression, tiling array, behaviour, methylation
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-70159 (URN)10.1186/1471-2164-13-59 (DOI)000301440800001 ()
    Merknad

    funding agencies|Swedish Research Council| 2008-14496-59340-36 |Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning| 221 2007 838 |

    Tilgjengelig fra: 2011-08-22 Laget: 2011-08-22 Sist oppdatert: 2019-03-05bibliografisk kontrollert
    2. Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
    Åpne denne publikasjonen i ny fane eller vindu >>Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
    Vise andre…
    2016 (engelsk)Inngår i: Royal Society Open Science, E-ISSN 2054-5703, nr 3, artikkel-id 160033Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    The domestication of animals has generated a set of phenotypicmodifications, affecting behaviour, appearance, physiologyand reproduction, which are consistent across a range ofspecies. We hypothesized that some of these phenotypes couldhave evolved because of genetic correlation to tameness,an essential trait for successful domestication. Starting froman outbred population of red junglefowl, ancestor of alldomestic chickens, we selected birds for either high or lowfear of humans for five generations. Birds from the fifthselected generation (S5) showed a divergent pattern of growthand reproduction, where low fear chickens grew larger andproduced larger offspring. To examine underlying geneticmechanisms, we used microarrays to study gene expressionin thalamus/hypothalamus, a brain region involved in fearand stress, in both the parental generation and the S5. Whileparents of the selection lines did not show any differentiallyexpressed genes, there were a total of 33 genes with adjustedp-values below 0.1 in S5. These were mainly related to spermfunction,immunological functions, with only a few known tobe relevant to behaviour. Hence, five generations of divergentselection for fear of humans produced changes in hypothalamicgene expression profiles related to pathways associated withmale reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis thatdomesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

    sted, utgiver, år, opplag, sider
    Royal Society Publishing, 2016
    Emneord
    artificial selection, gene expression, microarray, chicken, fearfulness
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-130501 (URN)10.1098/rsos.160033 (DOI)000384411000002 ()
    Merknad

    Funding agencies:  Research council Formas; Vetenskapsradet; ERC [322206]

    Tilgjengelig fra: 2016-08-11 Laget: 2016-08-11 Sist oppdatert: 2017-11-28
    Fulltekst (pdf)
    Chicken domestication: Effects of tameness on brain gene expression and DNA methylation
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    presentationsbild
  • 286.
    Bélteky, Johan
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Agnvall, Beatrix
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Bektic, Lejla
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Höglund, Andrey
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Guerrero Bosagna, Carlos
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Epigenetics and early domestication: differences in hypothalamic DNA methylation between red junglefowl divergently selected for high or low fear of humans2018Inngår i: Genetics Selection Evolution, ISSN 0999-193X, E-ISSN 1297-9686, Vol. 50, artikkel-id 13Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Domestication of animals leads to large phenotypic alterations within a short evolutionary time-period. Such alterations are caused by genomic variations, yet the prevalence of modified traits is higher than expected if they were caused only by classical genetics and mutations. Epigenetic mechanisms may also be important in driving domesticated phenotypes such as behavior traits. Gene expression can be modulated epigenetically by mechanisms such as DNA methylation, resulting in modifications that are not only variable and susceptible to environmental stimuli, but also sometimes transgenerationally stable. To study such mechanisms in early domestication, we used as model two selected lines of red junglefowl (ancestors of modern chickens) that were bred for either high or low fear of humans over five generations, and investigated differences in hypothalamic DNA methylation between the two populations. Results: Twenty-two 1-kb windows were differentially methylated between the two selected lines at p amp;lt; 0.05 after false discovery rate correction. The annotated functions of the genes within these windows indicated epigenetic regulation of metabolic and signaling pathways, which agrees with the changes in gene expression that were previously reported for the same tissue and animals. Conclusions: Our results show that selection for an important domestication-related behavioral trait such as tameness can cause divergent epigenetic patterns within only five generations, and that these changes could have an important role in chicken domestication.

    Fulltekst (pdf)
    fulltext
  • 287.
    Bélteky, Johan
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Agnvall, Beatrix
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Johnsson, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Wright, Dominic
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology2016Inngår i: Royal Society Open Science, E-ISSN 2054-5703, nr 3, artikkel-id 160033Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The domestication of animals has generated a set of phenotypicmodifications, affecting behaviour, appearance, physiologyand reproduction, which are consistent across a range ofspecies. We hypothesized that some of these phenotypes couldhave evolved because of genetic correlation to tameness,an essential trait for successful domestication. Starting froman outbred population of red junglefowl, ancestor of alldomestic chickens, we selected birds for either high or lowfear of humans for five generations. Birds from the fifthselected generation (S5) showed a divergent pattern of growthand reproduction, where low fear chickens grew larger andproduced larger offspring. To examine underlying geneticmechanisms, we used microarrays to study gene expressionin thalamus/hypothalamus, a brain region involved in fearand stress, in both the parental generation and the S5. Whileparents of the selection lines did not show any differentiallyexpressed genes, there were a total of 33 genes with adjustedp-values below 0.1 in S5. These were mainly related to spermfunction,immunological functions, with only a few known tobe relevant to behaviour. Hence, five generations of divergentselection for fear of humans produced changes in hypothalamicgene expression profiles related to pathways associated withmale reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis thatdomesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

    Fulltekst (pdf)
    fulltext
  • 288. Bestill onlineKjøp publikasjonen >>
    Börjesson, Stefan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Antibiotic Resistance in Wastewater: Methicillin-resistant Staphylococcus aureus (MRSA)and antibiotic resistance genes2009Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    A large part of the antibiotics consumed ends up in wastewater, and in the wastewater the antibiotics may exert selective pressure for or maintain resistance among microorganisms. Antibiotic resistant bacteria and genes encoding antibiotic resistance are commonly detected in wastewater, often at higher rates and concentrations compared to surface water. Wastewater can also provide favourable conditions for the growth of a diverse bacterial community, which constitutes a basis for the selection and spread of antibiotic resistance. Therefore, wastewater treatment plants have been suggested to play a role in the dissemination and development of antibiotic resistant bacteria. Methicillin-resistant Staphylococcus aureus (MRSA) is a large problem worldwide as a nosocomial pathogen, but knowledge is limited about occurrence in non-clinical environments, such as wastewater, and what role wastewater plays in dissemination and development of MRSA.

     

    In this thesis we investigated the occurrence of MRSA in a full-scale wastewater treatment plant (WWTP). We also investigated the concentration of genes encoding resistance to aminoglycosides (aac(6’)-Ie+aph(2’’)), β-lactam antibiotics (mecA) and tetracyclines (tetA and tetB) in three wastewater-associated environments: (1) soil from an overland flow area treating landfill leachates, (2) biofilm from a municipal wastewater treatment plant, and (3) sludge from a hospital wastewater pipeline. In addition, concentrations of mecA, tetA and tetB were investigated over the treatment process in the WWTP. These investigations were performed to determine how the prevalence and concentration of MRSA and the antibiotic resistence genes are affected in wastewater and wastewater treatment processes over time. The occurrence of MRSA was investigated by cultivation and a commercially available real-time PCR assay. In order to determine concentrations of the genes aac(6’)-Ie+aph(2’’), mecA, tetA and tetB in wastewater we developed a LUXTM real-time PCR assay for each gene.

     

    Using cultivation and real-time PCR we could for the first time describe the occurrence of MRSA in wastewater and show that it had a stable occurrence over time in a WWTP. MRSA could mainly be detected in the early treatment steps in the WWTP, and the wastewater treatment process reduced the number and diversity of cultivated MRSA. However, our results also indicate that the treatment process selects for strains with more extensive resistance and possibly higher virulence. The isolated wastewater MRSA strains were shown to have a close genetic relationship to clinical isolates, and no specific wastewater lineages could be detected, indicating that they are a reflection of carriage in the community. Taken together, these data indicate that wastewater may be a potential reservoir for MRSA and that MRSA are more prevalent in wastewater than was previously thought.

     

    The real-time PCR assays, for aac(6’)-Ie+aph(2’’), mecA, tetA, and tetB that we developed, were shown to be sensitive, fast, and reproducible methods for detection and quantification of these genes in wastewater environments. The highest concentrations of all genes were observed in the hospital pipeline, and the lowest in the overland flow system, with tetA and aac(6´)-Ie+aph(2´´) detected in all three environments. In the full-scale WWTP, we continuously detected mecA, tetA and tetB over the treatment process and over time. In addition, it was shown that the treatment process reduces concentrations of all three genes. The data presented in this thesis also indicate that the reduction for all three genes may be connected to the removal of biomass, and in the reduction of tetA and tetB, sedimentation and precipitation appear to play an important role.

    Delarbeid
    1. Quantification of genes encoding resistance to aminoglycosides, β-lactams and tetracyclines in wastewater environments by real-time PCR
    Åpne denne publikasjonen i ny fane eller vindu >>Quantification of genes encoding resistance to aminoglycosides, β-lactams and tetracyclines in wastewater environments by real-time PCR
    Vise andre…
    2009 (engelsk)Inngår i: International Journal of Environmental Health Research, ISSN 0960-3123, E-ISSN 1369-1619, s. 1-12Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    In this study real-time PCR assays, based on the LUX-technique, were developed for quantification of genes mediating resistance to aminoglycosides [aac(6 ')-Ie + aph(2 ' ')], beta-lactams (mecA), and tetracyclines (tetA and tetB), for use in wastewater environments. The developed assays were applied on DNA extracted from three wastewater-associated environments: soil from an overland flow area treating landfill leachates, biofilm from a municipal wastewater treatment plant, and sludge from a hospital wastewater pipeline. The highest concentration of all genes was observed in the hospital pipeline and the lowest in the overland flow system. TetA and aac(6 ')-Ie + aph(2 ' ') could be detected in all environments. The tetB gene was detected in the overland flow area and the hospital wastewater pipeline and mecA was detected in the wastewater treatment plant and the hospital pipeline. The developed LUX real-time PCR assays were shown to be fast and reproducible tools for detection and quantification of the four genes encoding antibiotic resistance in wastewater.

    sted, utgiver, år, opplag, sider
    Taylor & Francis, 2009
    Emneord
    Water pollutants; sewage pollution; water quality; aac(6')-Ie + aph(2''); mecA; tetA; tetB; LUX™ real-time PCR
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-18293 (URN)10.1080/09603120802449593 (DOI)19370439 (PubMedID)
    Tilgjengelig fra: 2009-05-15 Laget: 2009-05-15 Sist oppdatert: 2017-12-13bibliografisk kontrollert
    2. A seasonal study of the mecA gene and Staphylococcus aureus including methicillin-resistant S. aureus in a municipal wastewater treatment plant
    Åpne denne publikasjonen i ny fane eller vindu >>A seasonal study of the mecA gene and Staphylococcus aureus including methicillin-resistant S. aureus in a municipal wastewater treatment plant
    2009 (engelsk)Inngår i: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 43, nr 4, s. 925-932Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    The spread of methicillin-resistant Staphylococcus aureus (MRSA), in which the mecA gene mediates resistance, threatens the treatment of staphylococcal diseases. The aims were to determine the effect of wastewater treatment processes on mecA gene concentrations, and the prevalence of S. aureus and MRSA over time. To achieve this a municipal wastewater treatment plant was investigated for the mecA gene, S. aureus and MRSA, using real-time PCR assays. Water samples were collected monthly for one year, at eight sites in the plant, reflecting different aspects of the treatment process. The mecA gene and S. aureus could be detected throughout the year at all sampling sites. MRSA could also be detected, but mainly in the early treatment steps. The presence of MRSA was verified through cultivation from inlet water. The concentration of the mecA gene varied between months and sampling sites, but no obvious seasonal variation could be determined. The wastewater treatment process reduced the mecA gene concentration in most months. Taken together our results show that the mecA gene, S. aureus and MRSA occur over the year at all sites investigated.

    Emneord
    Methicillin-resistant, Staphylococcus aureus, mecA, LUX (TM) real-time PCR, spa Typing, Wastewater treatment plant, Seasonal study
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-17599 (URN)10.1016/j.watres.2008.11.036 (DOI)19084256 (PubMedID)
    Merknad
    Original Publication: Stefan Börjesson, Sara Melin, Andreas Matussek and Per-Eric Lindgren, A seasonal study of the mecA gene and Staphylococcus aureus including methicillin-resistant S. aureus in a municipal wastewater treatment plant, 2009, Water Research, (43), 4, 925-932. http://dx.doi.org/10.1016/j.watres.2008.11.036 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Tilgjengelig fra: 2009-07-09 Laget: 2009-04-06 Sist oppdatert: 2017-12-13bibliografisk kontrollert
    3. Methicillin-resistant Staphylococcus aureus (MRSA) in municipal wastewater: An uncharted threat?
    Åpne denne publikasjonen i ny fane eller vindu >>Methicillin-resistant Staphylococcus aureus (MRSA) in municipal wastewater: An uncharted threat?
    Vise andre…
    (engelsk)Manuskript (Annet vitenskapelig)
    Abstract [en]

    Methicillin-resistant S. aureus (MRSA) was recently detected in municipal wastewater, why there is a need for further studies to elucidate if MRSA in wastewater constitutes a health risk, and to determine how wastewater treatment processes affects MRSA. We cultivated MRSA from a full-scale wastewater treatment plant to characterise the indigenous MRSA-flora and to investigate how the wastewater treatment process affects the clonal distribution. MRSA isolates were characterised using spa typing, antibiograms, SSCmec typing and detection of Panton Valentine leukocidin (PVL) genes. We found that the wastewater MRSA-flora has a close genetic relationship to clinical isolates, but we also isolated novel spa types, primarily from the activated sludge treatment step. The number of isolates and the diversity of MRSA are reduced by the treatment process, but the process also selects for more extensive antibiotic resistant strains as well as for PVL positive strains.

    Emneord
    Staphylococcus aureus, MRSA, methicillin, β-lactam, SCCmec, spa typing, Panton Valentine leukocidin, PVL, antibiotic resistance, antibiogram
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-18295 (URN)
    Tilgjengelig fra: 2009-05-15 Laget: 2009-05-15 Sist oppdatert: 2010-01-14bibliografisk kontrollert
    4. Genes encoding tetracycline resistance in a full-scale municipal wastewater treatment plant investigated during one year
    Åpne denne publikasjonen i ny fane eller vindu >>Genes encoding tetracycline resistance in a full-scale municipal wastewater treatment plant investigated during one year
    (engelsk)Manuskript (Annet vitenskapelig)
    Abstract [en]

    Tetracycline-resistant bacteria and genes encoding tetracycline resistance are common in anthropogenic environments. We studied how wastewater treatment affects the prevalence and concentration of two genes that encode resistance to tetracycline: tetA and tetB. Using real-time PCR we analysed wastewater samples collected monthly for one year at eight key-sites in a full-scale municipal wastewater treatment plant (WWTP). We detected tetA and tetB at each sampling site and the concentration of both genes, expressed per wastewater volume or per total-DNA, decreased over the treatment process. The reduction of tetA and tetB was partly the result of the sedimentation process. The ratio of tetA and tetB, respectively, to total DNA was lower in or after the biological processes. Taken together our data show that tetracycline resistance genes occur throughout the WWTP and that the concentrations are reduced under conventional operational strategies. However, it is not possible to conclude the eventual risk for humans with respect to resistance spreading.

    Emneord
    tetA, tetB, tetracycline, LUXTM real-time PCR, wastewater treatment plant
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-18296 (URN)
    Tilgjengelig fra: 2009-05-15 Laget: 2009-05-15 Sist oppdatert: 2010-01-14bibliografisk kontrollert
    Fulltekst (pdf)
    Antibiotic Resistance in Wastewater
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  • 289.
    Calais, Andreas
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Is personality dependent of growth rate in red junglefowl (Gallus gallus)?2013Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    Personality has been reported in a large variety of animal species, but it is not obvious why animals have personality. Variation in physiological traits, such as growth rate, should theoretically affect variation in behaviours and thus can explain why we observe variation in personalities. Growth rate is, theoretically, positively correlated with active personality types. Empirical studies have reported this pattern in different fish species, but there are not yet many studies on endothermic animals. I have therefore scored behaviours of 100 red junglefowl (Gallus gallus) chicks in four personality assays; novel arena, novel object, tonic immobility, and a proactive-reactive test, together with recording variation in growth rate of these individuals. The chicks individual growth rate (% day-1) were calculated and the relationship between personality and growth rate investigated. There was significant difference in growth rate between the sexes, where males grew faster than females, detected already at one week of age. However, no significant correlations between behavioural traits and growth rate were observed, indicating that personality seem to be independent of growth rate. Further studies should therefore investigate the generality of this finding, and alternative underlying mechanisms for variation in personality should be explored.

    Fulltekst (pdf)
    Is personality dependent of growth rate in red junglefowl (Gallus gallus)?
  • 290.
    Calais, Andreas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Poor welfare or future investment? Different growth pattern of broiler breeders2015Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    The parental stock of meat type chickens (broiler breeders) are commonly feed restricted to decrease their rapid growth and the issues associated with it. Among these birds, chronic hunger and stress are the most prominent welfare concerns and mass heterogeneity within flocks a major management challenge. The present study compared small and large broiler breeders of the same age within a flock, with the hypothesis that small birds would show signs of poorer welfare indicated by higher corticosterone concentration and heterophil/lymphocyte ratio as a consequence of higher experienced feed restriction due to competition. It also aimed to characterize morphometric differences between small and large birds within flocks as well as between birds on different feeding regimens; skip-a-day vs. every-day-fed. Heterophil/lymphocyte ratio at 4 weeks was significantly higher in large birds compared to small birds, but corticosterone concentration did not differ. Relative mass of the upper gastrointestinal tract, pancreas and liver of small birds at 4 weeks of age were significantly larger, while relative muscle and gizzard fat mass were significantly lower compared to large birds. 12 weeks old skip-a-day fed birds largely followed the pattern of 4 weeks old small birds. In the present study, no clear signs of poorer welfare in small broiler breeders could be seen and the morphometric differences might suggest different ways to cope with feed competition. A larger gastrointestinal tract might indicate long-term investments and maybe that smaller broiler breeders, and skip-a-day fed birds, are better habituated to feed restriction.

    Fulltekst (pdf)
    Poor welfare or future investment? Different growth pattern of broiler breeders
  • 291.
    Camacho, Rafael
    et al.
    Lund University, Sweden.
    Meyer, Matthias
    Lund University, Sweden.
    Vandewal, Koen
    Technical University of Dresden, Germany.
    Tang, Zheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Scheblykin, Ivan G.
    Lund University, Sweden.
    Polarization Imaging of Emissive Charge Transfer States in Polymer/Fullerene Blends2014Inngår i: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 26, nr 23, s. 6695-6704Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Photoexcitation of conjugated polymerfullerene blends results in population of a local charge transfer (CT) state at the interface between the two materials. The competition between recombination and dissociation of this interfacial state limits the generation of fully separated free charges. Therefore, a detailed understanding of the CT states is critical for building a comprehensive picture of the organic solar cells operation. We applied a new fluorescence microscopy method called two-dimensional polarization imaging to gain insight into the orientation of the transition dipole moments of the CT states, and the associated excitation energy transfer processes in TQ1:PCBM blend films. The polymer phase was oriented mechanically to relate the polymer dipole moment orientation to that of the CT states. CT state formation was observed to be much faster than energy transfer in the polymer phase. However, after being formed an emissive CT state does not exchange excitation energy with other CT states, suggesting that they are spatially and/or energetically isolated. We found that the quantum yield of the CT emission is smaller for CT states spatially located in the highly oriented polymer domains, which is interpreted as the result of enhanced CT state dissociation in highly ordered structures.

  • 292.
    Campos, Alexandre
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten.
    Danielsson, Gabriela
    Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden.
    Farinha, Ana Paula
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten.
    Kuruvilla, Jacob
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten.
    Warholm, Per
    Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden.
    Cristobal, Susana
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten. Linköping University.
    Shotgun proteomics to unravel marine mussel (Mytilus edulis) response to long-term exposure to low salinity and propranolol in a Baltic Sea microcosm2016Inngår i: Journal of Proteomics, ISSN 1874-3919, E-ISSN 1876-7737, Vol. 137, s. 97-106Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pharmaceuticals, among them the β-adrenoreceptor blocker propranolol, are an important group of environmental contaminants reported in European waters. Laboratory exposure to pharmaceuticals on marine species has been performed without considering the input of the ecosystem flow. To unravel the ecosystem response to long-term exposure to propranolol we have performed long-term exposure to propranolol and low salinity in microcosms. We applied shotgun proteomic analysis to gills of Mytilus edulis from those Baltic Sea microcosms and identified 2071 proteins with a proteogenomic strategy. The proteome profiling patterns from the 587 highly reproductive proteins among groups define salinity as a key factor in the mussel´s response to propranolol. Exposure at low salinity drives molecular mechanisms of adaptation based on a decrease in the abundance of several cytoskeletal proteins, signalling and intracellular membrane trafficking pathway combined with a response towards the maintenance of transcription and translation. The exposure to propranolol combined with low salinity modulates the expression of structural proteins including cilia functions and decrease the expression membrane protein transporters. This study reinforces the environment concerns of the impact of low salinity in combination with anthropogenic pollutants and anticipate critical physiological conditions for the survival of the blue mussel in the northern areas.

  • 293.
    Campoy-Quiles, M.
    et al.
    ICMAB CSIC, Spain.
    Müller, Christian
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan. ICMAB CSIC, Spain.
    Garriga, M.
    ICMAB CSIC, Spain.
    Wang, E.
    Chalmers, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Alonso, M. I.
    ICMAB CSIC, Spain.
    On the complex refractive index of polymer:fullerene photovoltaic blends2014Inngår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 571, s. 371-376Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a detailed investigation of the refractive index of polymer:fullerene blends for photovoltaic applications. The donor polymers poly[2,7-(9,9-dioctylfluorene)-alt-5,5-(4,7-di-2-thienyl-2,1,3-benzothiadiazole)] (APFO3), poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1), and poly[2,7-(9,9-dioctylfluorene)-alt-5,5-(5,10-di-2-thienyl-2,3,7,8-tetraphenyl-pyrazino[2,3-g] quinoxaline)] (APFO-Green9) were blended with either [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) or [6,6]-phenyl-C-71-butyric acid methyl ester (PC71BM). We measured variable angle spectroscopic ellipsometry for three systems, namely APFO3:PCBM, TQ1:PC71BM and APFO-Green9:PC71BM, as a function of composition and analyze the data employing a number of models. We found that Bruggeman effective medium approximations (EMA) are not precise for the description of the optical properties of these blends. This is due to a number of reasons. First, we find that there are energy shifts associated to changes in conjugation length that cannot be accounted for using EMA. Second, blending results in a strong reduction of anisotropy. Finally, our data suggest that there is some degree of vertical segregation between components. Therefore, our results support the idea that the optical properties of polymer:fullerene mixtures should be treated as alloys rather than non-interacting blends.

  • 294.
    Cantù, Claudio
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Medicinska fakulteten. Univ Zurich, Switzerland.
    Felker, Anastasia
    Univ Zurich, Switzerland.
    Zimmerli, Dario
    Univ Zurich, Switzerland.
    Prummel, Karin D.
    Univ Zurich, Switzerland.
    Cabello, Elena M.
    Univ Zurich, Switzerland.
    Chiavacci, Elena
    Univ Zurich, Switzerland; Int Ctr Genet Engn and Biotechnol ICGEB Trieste, Italy.
    Mendez-Acevedo, Kevin M.
    Max Delbruck Ctr Mol Med, Germany.
    Kirchgeorg, Lucia
    Univ Zurich, Switzerland.
    Burger, Sibylle
    Univ Zurich, Switzerland.
    Ripoll, Jorge
    Univ Carlos III Madrid, Spain.
    Valenta, Tomas
    Univ Zurich, Switzerland.
    Hausmann, George
    Univ Zurich, Switzerland.
    Vilain, Nathalie
    Ecole Polytech Fed Lausanne, Switzerland.
    Aguet, Michel
    Ecole Polytech Fed Lausanne, Switzerland.
    Burger, Alexa
    Univ Zurich, Switzerland.
    Panakova, Daniela
    Max Delbruck Ctr Mol Med, Germany; Deutsch Zentrum Herz Kreislauf Forsch DZHK, Germany.
    Basler, Konrad
    Univ Zurich, Switzerland.
    Mosimann, Christian
    Univ Zurich, Switzerland.
    Mutations in Bcl9 and Pygo genes cause congenital heart defects by tissue-specific perturbation of Wnt/beta-catenin signaling2018Inngår i: Genes & Development, ISSN 0890-9369, E-ISSN 1549-5477, Vol. 32, nr 21-22, s. 1443-1458Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bcl9 and Pygopus (Pygo) are obligate Wnt/beta-catenin cofactors in Drosophila, yet their contribution to Wnt signaling during vertebrate development remains unresolved. Combining zebrafish and mouse genetics, we document a conserved, beta-catenin-associated function for BCL9 and Pygo proteins during vertebrate heart development. Disrupting the beta-catenin-BCL9-Pygo complex results in a broadly maintained canonical Wnt response yet perturbs heart development and proper expression of key cardiac regulators. Our work highlights BCL9 and Pygo as selective beta-catenin cofactors in a subset of canonical Wnt responses during vertebrate development. Moreover, our results implicate alterations in BCL9 and BCL9L in human congenital heart defects.

    Fulltekst (pdf)
    fulltext
  • 295.
    Cantù, Claudio
    et al.
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Grande, Vito
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Alborelli, Ilaria
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Cassinelli, Letizia
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Cantù, Ileana
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Colzani, Maria Teresa
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Ierardi, Rossella
    San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET), San Raffaele Scientific Institute, 20132 Milan, Italy.
    Ronzoni, Luisa
    Dipartimento di Medicina Interna, Università di Milano, Fondazione Policlinico Mangiagalli, Regina Elena, IRCCS, Milano, Italy.
    Cappellini, Maria Domenica
    Dipartimento di Medicina Interna, Università di Milano, Fondazione Policlinico Mangiagalli, Regina Elena, IRCCS, Milano, Italy.
    Ferrari, Giuliana
    San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET), San Raffaele Scientific Institute, 20132 Milan // Vita-Salute San Raffaele University, Milan, Italy.
    Ottolenghi, Sergio
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    Ronchi, Antonella
    Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy.
    A highly conserved SOX6 double binding site mediates SOX6 gene downregulation in erythroid cells2011Inngår i: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 39, nr 2, s. 486-501Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Sox6 transcription factor plays critical roles in various cell types, including erythroid cells. Sox6-deficient mice are anemic due to impaired red cell maturation and show inappropriate globin gene expression in definitive erythrocytes. To identify new Sox6 target genes in erythroid cells, we used the known repressive double Sox6 consensus within the εy-globin promoter to perform a bioinformatic genome-wide search for similar, evolutionarily conserved motifs located within genes whose expression changes during erythropoiesis. We found a highly conserved Sox6 consensus within the Sox6 human gene promoter itself. This sequence is bound by Sox6 in vitro and in vivo, and mediates transcriptional repression in transient transfections in human erythroleukemic K562 cells and in primary erythroblasts. The binding of a lentiviral transduced Sox6FLAG protein to the endogenous Sox6 promoter is accompanied, in erythroid cells, by strong downregulation of the endogenous Sox6 transcript and by decreased in vivo chromatin accessibility of this region to the PstI restriction enzyme. These observations suggest that the negative Sox6 autoregulation, mediated by the double Sox6 binding site within its own promoter, may be relevant to control the Sox6 transcriptional downregulation that we observe in human erythroid cultures and in mouse bone marrow cells in late erythroid maturation.

  • 296.
    Cantù, Claudio
    et al.
    Institute of Molecular Life Sciences, University of Zurich, Switzerland.
    Valenta, Tomas
    Institute of Molecular Life Sciences, University of Zurich, Switzerland.
    Basler, Konrad
    Institute of Molecular Life Sciences, University of Zurich, Switzerland.
    A RING finger to wed TCF and β-catenin2013Inngår i: EMBO Reports, ISSN 1469-221X, E-ISSN 1469-3178, Vol. 14, nr 4, s. 295-296Artikkel i tidsskrift (Fagfellevurdert)
  • 297.
    Cao, Z.
    et al.
    Department of Chemical Science and Technologies, University of Tor Vergata, Rome, Italy, Department of Chemistry and Molecular Engineering, East China University of of Science and Technology, Shanghai, China.
    Lvova, L.
    Department of Chemical Science and Technologies, University of Tor Vergata, Rome, Italy, Faculty of Biology and Soil Science, St. Petersburg State University, St. Petersburg, Russia.
    Paolesse, R.
    Department of Chemical Science and Technologies, University of Tor Vergata, Rome, Italy.
    Di Natale, C
    Department of Electronic Engineering, University of Tor Vergata, Rome, Italy.
    D' Amico, A.
    Department of Electronic Engineering, University of Tor Vergata, Rome, Italy.
    Lundström, Ingemar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska högskolan.
    Porphyrin electropolymers as opto-electrochemical probe for the detection of red-ox analytes2014Inngår i: Sensors: Proceedings of the First National Conference on Sensors, Rome 15-17 February, 2012, Springer Science Business Media , 2014, Vol. 162 LNEE, s. 49-55Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The application of pyrrole-substituted porphyrin electropolymers for simultaneous optical and electrochemical analysis of red-ox active analytes, namely diazo-conjugated dyes of Sudan family, is presented. Sudan colorants are widely used in many fields, but accurate screening of their consumption is required due to their high toxicity. The inherent electrochemical activity of Sudan dyes, as far as their intense coloration, makes possible to find the appropriate conditions of hybrid optical and electrochemical porphyrin electropolymer based sensor array system application. This approach allowed a significant increase in the chemical information, improving the analytical system performance in terms of selectivity and sensitivity, and permitted the fast and simple monitoring of Sudan dye analytes.

  • 298.
    Cardemil, Carina
    Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy at the University of Gothenburg, Göteborg, Sweden.
    Effects of antiresorptive agents on inflammation and bone regeneration in different osseous sites - experimental and clinical studies2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The biological mechanisms involved in bone regeneration in osteoporotic bone and the effect of antiresorptive drugs in relation to surgically inserted biomaterials are not fully understood. Improved osseointegration of titanium implants but also adverse effects of antiresorptive therapies, such as osteonecrotic jaw have been described in the literature. The aims of this research project were, firstly, to investigate and to understand the biological events determining bone regeneration and implant integration, after administration of antiresorptive agents; secondly, to determine the cellular and molecular patterns of bone regeneration at implants and synthetic bone substitutes under osteoporotic conditions and, thirdly, to determine how different skeletal sites are affected. The present research included a study of jawbone morphology and gene expression in patients treated with systemic bisphosphonates. When compared to controls, higher gene expression levels of IL-1β was observed in bisphosphonate treated patients with osteonecrosis while bisphosphonate treated patients without necrosis showed lower expression levels of caspase 8, an apoptosis marker involved in the immune response. In ovariectomised rats, zoledronic acid resulted in site-specific differences in the rate of osseointegration and also of gene expression involved in bone healing and regeneration. Strontium-doped calcium phosphate inserted in the rat femur induced lower expression of osteoclastic markers compared to hydroxyapatite and higher bone formation in the periphery of the defects. Whereas major structural changes were demonstrated in the long bones of the ovariectomised rat, less structural alterations were shown in the mandible. However, ovariectomy resulted in lower expression of genes coding for bone formation and angiogenesis in the mandible. In conclusion, the present study shows that the mandible is differently affected by experimentally induced estrogen deficiency than the long bones. Bisphosphonates, administered systemically to estrogen deficient animals, impair osseointegration in the mandible, at least partly related to a downregulation of genes important for the osteogenic process. These observations may have implications for understanding the mechanisms involved in the deranged bone healing observed in the jawbone of bisphosphonate treated patients.

    Delarbeid
    1. The effects of a systemic single dose of zoledronic acid on post-implantation bone remodelling and inflammation in an ovariectomised rat model.
    Åpne denne publikasjonen i ny fane eller vindu >>The effects of a systemic single dose of zoledronic acid on post-implantation bone remodelling and inflammation in an ovariectomised rat model.
    Vise andre…
    2013 (engelsk)Inngår i: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 34, nr 5, s. 1546-1561Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Bisphosphonates reverse the negative effects of ovariectomy on bone, but they have also been associated with adverse processes in human jawbone. The molecular events determining bone regeneration and implant integration in osteoporotic conditions, with and without bisphosphonate treatment, are unclear. In this study, ovariectomised rats, to which a single dose of saline (NaCl) or zoledronic acid (Zol) was administered, received titanium alloy implants in their tibiae and mandibles. An enzyme-linked immunosorbent assay, gene expression analysis and histomorphometry were performed. The results show that ovariectomy, per se, upregulated the expression of genes denoting bone formation in the tibia, bone remodelling in the mandible and apoptosis in the tibia and mandible. Zoledronic acid administration resulted in lower levels of a remodelling marker in serum and downregulated gene expression for inflammation, bone formation, angiogenesis and apoptosis, mainly in the mandible, after 28 d of healing. Histomorphometry revealed improved bone-to-implant contact in the tibia, while the opposite was observed in the mandible. The present data show that a systemic single dose of zoledronic acid, in ovariectomised animals, results in site-specific differences in the regulation of genes involved in bone healing and regeneration in association with implant installation. These events occur in parallel with site-specific differences in the rate of osseointegration, indicating diverse tissue responses in the tibia and mandible after zoledronic acid treatment. The zoledronic acid effect on gene expression, during the late phase of healing in the mandible, suggests negative effects by the anti-resorptive agent on osseointegration at that particular site.

    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-135755 (URN)10.1016/j.biomaterials.2012.11.003 (DOI)23182921 (PubMedID)
    Tilgjengelig fra: 2017-03-21 Laget: 2017-03-21 Sist oppdatert: 2018-01-13
    2. Strontium-doped calcium phosphate and hydroxyapatite granules promote different inflammatory and bone remodelling responses in normal and ovariectomised rats
    Åpne denne publikasjonen i ny fane eller vindu >>Strontium-doped calcium phosphate and hydroxyapatite granules promote different inflammatory and bone remodelling responses in normal and ovariectomised rats
    Vise andre…
    2013 (engelsk)Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, nr 12, artikkel-id e84932Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    The healing of bone defects may be hindered by systemic conditions such as osteoporosis. Calcium phosphates, with or without ion substitutions, may provide advantages for bone augmentation. However, the mechanism of bone formation with these materials is unclear. The aim of this study was to evaluate the healing process in bone defects implanted with hydroxyapatite (HA) or strontium-doped calcium phosphate (SCP) granules, in non-ovariectomised (non-OVX) and ovariectomised (OVX) rats. After 0 (baseline), six and 28d, bone samples were harvested for gene expression analysis, histology and histomorphometry. Tumour necrosis factor-α (TNF-α), at six days, was higher in the HA, in non-OVX and OVX, whereas interleukin-6 (IL-6), at six and 28d, was higher in SCP, but only in non-OVX. Both materials produced a similar expression of the receptor activator of nuclear factor kappa-B ligand (RANKL). Higher expression of osteoclastic markers, calcitonin receptor (CR) and cathepsin K (CatK), were detected in the HA group, irrespective of non-OVX or OVX. The overall bone formation was comparable between HA and SCP, but with topological differences. The bone area was higher in the defect centre of the HA group, mainly in the OVX, and in the defect periphery of the SCP group, in both non-OVX and OVX. It is concluded that HA and SCP granules result in comparable bone formation in trabecular bone defects. As judged by gene expression and histological analyses, the two materials induced different inflammatory and bone remodelling responses. The modulatory effects are associated with differences in the spatial distribution of the newly formed bone.

    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-136113 (URN)10.1371/journal.pone.0084932 (DOI)24376855 (PubMedID)
    Tilgjengelig fra: 2017-03-28 Laget: 2017-03-28 Sist oppdatert: 2018-01-13bibliografisk kontrollert
  • 299.
    Cardoso-Moreira, Margarida
    et al.
    Heidelberg Univ ZMBH, Germany; Univ Lausanne, Switzerland.
    Halbert, Jean
    Univ Lausanne, Switzerland.
    Valloton, Delphine
    Univ Lausanne, Switzerland.
    Velten, Britta
    European Mol Biol Lab, Germany.
    Chen, Chunyan
    Chinese Acad Sci, Peoples R China; Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Shao, Yi
    Chinese Acad Sci, Peoples R China; Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Liechti, Angelica
    Univ Lausanne, Switzerland.
    Ascencao, Kelly
    Univ Lausanne, Switzerland.
    Rummel, Coralie
    Univ Lausanne, Switzerland.
    Ovchinnikova, Svetlana
    Heidelberg Univ ZMBH, Germany.
    Mazin, Pavel V.
    Skolkovo Inst Sci and Technol, Russia; RAS, Russia; HSE Univ, Russia.
    Xenarios, Ioannis
    Univ Lausanne, Switzerland.
    Harshman, Keith
    Univ Lausanne, Switzerland.
    Mort, Matthew
    Cardiff Univ, Wales.
    Cooper, David N.
    Cardiff Univ, Wales.
    Sandi, Carmen
    Ecole Polytech Fed Lausanne, Switzerland.
    Soares, Michael J.
    Univ Kansas, MO USA; Childrens Mercy, MO USA.
    Ferreira, Paula G.
    Univ Porto, Portugal; Univ Porto, Portugal.
    Afonso, Sandra
    Univ Porto, Portugal.
    Carneiro, Miguel
    Univ Porto, Portugal; Univ Porto, Portugal.
    Turner, James M. A.
    Francis Crick Inst, England.
    VandeBerg, John L.
    Univ Texas Rio Grande Valley, TX USA; Univ Texas Rio Grande Valley, TX USA; Univ Texas Rio Grande Valley, TX USA; Univ Texas Rio Grande Valley, TX USA; Univ Texas Rio Grande Valley, TX USA; Univ Texas Rio Grande Valley, TX USA.
    Fallahshahroudi, Amir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Behr, Ruediger
    Leibniz Inst Primate Res DPZ, Germany; DZHK German Ctr Cardiovasc Res, Germany.
    Lisgo, Steven
    Newcastle Univ, England.
    Lindsay, Susan
    Newcastle Univ, England.
    Khaitovich, Philipp
    Skolkovo Inst Sci and Technol, Russia; Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Huber, Wolfgang
    European Mol Biol Lab, Germany.
    Baker, Julie
    Stanford Univ, CA 94305 USA.
    Anders, Simon
    Heidelberg Univ ZMBH, Germany.
    Zhang, Yong E.
    Chinese Acad Sci, Peoples R China; Chinese Acad Sci, Peoples R China; Chinese Acad Sci, Peoples R China.
    Kaessmann, Henrik
    Heidelberg Univ ZMBH, Germany.
    Gene expression across mammalian organ development2019Inngår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 571, nr 7766, s. 505-+Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The evolution of gene expression in mammalian organ development remains largely uncharacterized. Here we report the transcriptomes of seven organs (cerebrum, cerebellum, heart, kidney, liver, ovary and testis) across developmental time points from early organogenesis to adulthood for human, rhesus macaque, mouse, rat, rabbit, opossum and chicken. Comparisons of gene expression patterns identified correspondences of developmental stages across species, and differences in the timing of key events during the development of the gonads. We found that the breadth of gene expression and the extent of purifying selection gradually decrease during development, whereas the amount of positive selection and expression of new genes increase. We identified differences in the temporal trajectories of expression of individual genes across species, with brain tissues showing the smallest percentage of trajectory changes, and the liver and testis showing the largest. Our work provides a resource of developmental transcriptomes of seven organs across seven species, and comparative analyses that characterize the development and evolution of mammalian organs.

  • 300.
    Caren, Helena
    et al.
    University of Gothenburg, Sweden.
    Erichsen, Jennie
    University of Gothenburg, Sweden.
    Olsson, Linda
    University of Gothenburg, Sweden.
    Enerbäck, Charlotta
    University of Gothenburg, Sweden.
    Sjoberg, Rose-Marie
    University of Gothenburg, Sweden.
    Abrahamsson, Jonas
    University of Gothenburg, Sweden.
    Kogner, Per
    Childhood Canc Res Unit, SE-17176 Stockholm, Sweden .
    Martinsson, Tommy
    University of Gothenburg, Sweden.
    High-resolution array copy number analyses for detection of deletion, gain, amplification and copy-neutral LOH in primary neuroblastoma tumors: Four cases of homozygous deletions of the CDKN2A gene2008Inngår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 9, nr 353Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Neuroblastoma is a very heterogeneous pediatric tumor of the sympathetic nervous system showing clinically significant patterns of genetic alterations. Favorable tumors usually have near-triploid karyotypes with few structural rearrangements. Aggressive stage 4 tumors often have near-diploid or near-tetraploid karyotypes and structural rearrangements. Whole genome approaches for analysis of genome-wide copy number have been used to analyze chromosomal abnormalities in tumor samples. We have used array-based copy number analysis using oligonucleotide single nucleotide polymorphisms (SNP) arrays to analyze the chromosomal structure of a large number of neuroblastoma tumors of different clinical and biological subsets. Results: Ninety-two neuroblastoma tumors were analyzed with 50 K and/or 250 K SNP arrays from Affymetrix, using CNAG3.0 software. Thirty percent of the tumors harbored 1p deletion, 22% deletion of 11q, 26% had MYCN amplification and 45% 17q gain. Most of the tumors with 1p deletion were found among those with MYCN amplification. Loss of 11q was most commonly seen in tumors without MYCN amplification. In the case of MYCN amplification, two types were identified. One type displayed simple continuous amplicons; the other type harbored more complex rearrangements. MYCN was the only common gene in all cases with amplification. Complex amplification on chromosome 12 was detected in two tumors and three different overlapping regions of amplification were identified. Two regions with homozygous deletions, four cases with CDKN2A deletions in 9p and one case with deletion on 3p (the gene RBMS3) were also detected in the tumors. Conclusion: SNP arrays provide useful tools for high-resolution characterization of significant chromosomal rearrangements in neuroblastoma tumors. The mapping arrays from Affymetrix provide both copy number and allele-specific information at a resolution of 10-12 kb. Chromosome 9p, especially the gene CDKN2A, is subject to homozygous (four cases) and heterozygous deletions (five cases) in neuroblastoma tumors.

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