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  • 101.
    Bonow, Madeleine
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap. Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Geographia didactica2010Ingår i: Tradition och praxis i högre utbildning: tolv ämnesdidaktiska studier / [ed] Anders Burman, Ana Graviz, Johan Rönnby, Huddinge: Södertörns högskola , 2010, s. 163-190Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 102.
    Bonow, Madeleine
    Södertörns högskola, Institutionen för livsvetenskaper.
    "…med de skönaste ekelundar": en geografisk resamed Linné till 1700-talets Västergötland2007Ingår i: Geografiska Notiser, ISSN 0016-724X, nr 4, s. 7-15Artikel i tidskrift (Övrigt vetenskapligt)
  • 103.
    Bonow, Madeleine
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap. Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Rytkönen, Paulina
    Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap.
    Gastronomins (politiska) geografi2011Ingår i: Ymer, ISSN 0044-0477, s. 7-36Artikel i tidskrift (Övrigt vetenskapligt)
  • 104.
    Bonow, Madeleine
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi. Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap.
    Rytkönen, Paulina
    Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap.
    Gastronomy and tourism as a regional development tool- the case of Jämtland2012Ingår i: Advances in Food, Hospitality and Tourism, ISSN 2043-8907, Vol. 2, nr 1, s. 2-10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article highlights how farm dairies in Jämtland combine gastronomy and tourism as an integral part or a component in their marketing strategies. These activities have been promoted and supported by authorities and NGO’s. Farm dairies contribute to tourism by producing gastronomic products that can be served by local restaurants and hotels, but they are also visiting targets for tourists and create important work opportunities in the villages. As a precursor in using gastronomy and tourism to promote regional development the experiences of Jämtland are of a high relevance for the future development in Sweden

  • 105.
    Bonow, Madeleine
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Rytkönen, PaulinaSödertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap.
    Geografins (politiska) geografi: Ymer 20112011Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
  • 106.
    Bonow, Madeleine
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap. Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Svanberg, Ingvar
    Södertörns högskola, Institutionen för livsvetenskaper, Biologi.
    "Säg får jag bjuda ur sumpen på en sprittande ruda": En bortglömd läckerhet från gångna tiders prästgårdskök2011Ingår i: Ymer, ISSN 0044-0477, s. 147-169Artikel i tidskrift (Övrigt vetenskapligt)
  • 107.
    Bonow, Madeleine
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi. Södertörns högskola, Institutionen för livsvetenskaper, Måltidskunskap.
    Svanberg, Ingvar
    Institutionen för rysslandsstudier Uppsala universitet.
    Uppländska ruddammar: Ett bidrag till akvakulturens kulturhistoria2012Ingår i: Uppland: årsbok för medlemmarna i Upplands fornminnesförening och hembygdsförbund, ISSN 0566-3059, s. 123-152Artikel i tidskrift (Övrigt vetenskapligt)
  • 108.
    Borg, Malin
    Södertörns högskola, Institutionen för livsvetenskaper.
    Does eutrophication cause directional genetic selection in three-spined stickleback (Gasterosteus aculeatus)?: A study of multiple Baltic Sea populations.2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Human-induced eutrophication is indirectly affecting aquatic organisms by altering their environment. This brings on altered selective pressures and could thereby cause changes in the genetic composition of exposed populations. Since anthropogenic environmental changes are usually occurring at a much higher rate than naturally occurring changes, they force populations to adapt to the new conditions faster than normal. Here, I have studied populations of three-spined sticklebacks (Gasterosteus aculeatus) from four eutrophicated and four adjacent reference sites, along the coast of Finland, to investigate if this species has responded genetically to the human-induced eutrophication of the Baltic Sea. For this purpose I used amplified fragment length polymorphism (AFLP) and found distinctions in genetic composition between the two habitats, as well as similarities between populations from eutrophicated sites. This suggests a similar genetic response to eutrophicated conditions by stickleback populations from different geographical areas. Moreover I found a distinct geographic structure among three-spined sticklebacks in the Baltic Sea.

  • 109.
    Borg, Malin
    Södertörns högskola, Institutionen för livsvetenskaper.
    Does eutrophication cause directional genetic selection in three-spined sticklebacks (Gasterosteus aculeatus)?: A study of multiple Baltic Sea populations2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Human-induced eutrophication is indirectly affecting aquatic organisms by altering their environment. This brings on altered selective pressures and could thereby cause changes in the genetic composition of exposed populations. Since anthropogenic environmental changes are usually occurring at a much higher rate than naturally occurring changes, they force populations to adapt to the new conditions faster than normal. Here, I have studied populations of three-spined sticklebacks (Gasterosteus aculeatus) from four eutrophicated and four adjacent reference sites, along the coast of Finland, to investigate if this species has responded genetically to the human-induced eutrophication of the Baltic Sea. For this purpose I used amplified fragment length polymorphism (AFLP) and found distinctions in genetic composition between the two habitats, as well as similarities between populations from eutrophicated sites. This suggests a similar genetic response to eutrophicated conditions by stickleback populations from different geographical areas. Moreover I found a distinct geographic structure among three-spined sticklebacks in the Baltic Sea.

  • 110.
    Borglund, Hanna
    Södertörns högskola, Institutionen för livsvetenskaper.
    Governing the commons: A case-study of Rio Limpio National Park, Dominican Republic2011Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Due to scarce natural resources and problems of governing the commons, alternative management of the commons has again emerged. The earlier known governing methods used by international and state conservation are state or private ownership. Governing the commons with local institutions was brought to attention in 2009 by Elinor Ostrom.

    In this case-study of governing the commons, a national park is the objective. There are many stakeholders, with a focus on the community institution. The co-management of governing the national park between the local institution, the state and the NGO is analysed to find out if sustainable governance can be achieved in Rio Limpio National Park, and if so how? The rules are set on the conditions of the state about the regulations of the national park, although its protection is legitimized by the activities of the local institution.

    The regulation that prohibits the use of the natural resources within the park is enforced in a situation -where poor people are directly dependant on the natural resources and have few employment alternatives. This creates conflicts between the state, the NGO and the community of the environmental policies. The study has shown that increased benefits of the community, as with social protection and local participation in decision making, will lead to more successful nature resource management as well as sustainable development.

  • 111.
    Borgström, Ulrika
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Svalqvist, Louise
    Södertörns högskola, Institutionen för livsvetenskaper.
    Att berätta historia: En studie om museers verksamhet2009Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syftet med denna uppsats är att undersöka hur museer genom förmedlandet av historia formar sin verksamhet som besöksmål. För att få svar på detta har vi ställt oss följande frågor: Hur verkar museerna för att levandegöra och tolka historia? Vad har museerna för framtid? För vår undersökning har vi genomfört en djupgående analys av fyra museers verksamhet, Nordiska museet, Etnografiska museet, Historiska museet samt Naturhistoriska Riksmuseet. Dessa har analyserats genom intervjuer, observationer samt dokumentstudier. De teoretiska utgångspunkter vi använt oss av är hermeneutik, Foucaults definition av museer som institution samt storytelling. De slutsatser vi kommit fram till är följande: Museerna har utvecklats ifrån ett upplysningsideal till en mer postmodernistisk inriktning där de vill aktivera besökarna till att tänka själva. Museerna arbetar aktivt för att visa fler perspektiv i historieredovisningen och försöker på olika sätt finna nya sätt att aktivera besökarna för att ge en levande bild av det förflutna. I framtiden tror vi att museerna kommer att fortsätta denna utveckling mot att bli mer upplevelseorienterade samtidigt som de värnar om sin unicitet som kunskapsförmedlare och bevarare av vårt gemensamma svenska kulturarv. Tyvärr går utvecklingen mot en ökad centralisering vilket minskar mångfalden av museer samt ger färre möjligheter till fler tolkningar av historien.

  • 112.
    Borneskog, Annalinn
    Södertörns högskola, Institutionen för livsvetenskaper.
    Decentralisation in Babati: A case study on the impact of decentralisation on health service delivery in a Tanzanian city2010Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
  • 113.
    Borneskog, Annalinn
    Södertörns högskola, Institutionen för livsvetenskaper.
    The international association's interventions and governments role in disasters: Failures and Successes2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The debate on international intervention is a very difficult topic. As a main issue in it, the differences lies on decisions regarding - what, when and who. This essay will address the importance of accurate intervention in disaster affected states. It will identify what types of interventions that is most commonly used and if there is one type of intervention that are the most effective one. It will show if the disaster in it self related to the area in question will determine what kind of intervention that should be used – is the identification of them two the deciding factor or is there one particular intervention model that is better to use? The essay will also question whether intervention might lead to a weakened state sovereignty and if sovereignty has to be protected and be taken in consideration before any intervention can be done. To address this, recent history is analysed with two cases as examples – the Darfur conflict and Cyclone Nargis that struck Burma in 2008. The conflict in Darfur is a man-made disaster which  lead to plenty of suffering and many lost lives. Cyclone Nargis was a natural disaster which in it self caused many deaths. In Darfur the discussion regarding what, when and who delayed actions from the international association. It was also disrupted by the government in Khartoum constant refusals of help from the outside world. In Burma, relief could be sent in the initial phase, however, the government was hard to cooperate with, which made it quite impossible for the relief to reach all the affected areas. Putting the empirical part against those theories that has been brought up in this essay, the thesis of it has been answered with the conclusion that whether one type of intervention model is being used or another model, the most important part in any kind of intervention is that the humanitarian assistance along with the provision of needs for survival will reach those who has been affected by a disaster, also, not to create any kind of pressure against the affected state in question, this to prevent further conflicts.

  • 114.
    Boss, John
    Södertörns högskola, Institutionen för livsvetenskaper.
    Adaptive evolution of Transcription Factors in European and wine yeast2009Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The mutability of transcription factors (TF) is thought to be of high importance for the evolutionary change of living organisms. Transcription factors, coactivators, coregulators, kinases, chromatin remodelers conditional factors and other proteins together govern the timing and level of gene expression. About 10% of the genes in the human genome are predicted to be TFs and mutational changes in these genes or in the target regulatory sequences they bind will potentially give rise to evolutionary advantages or malfunctions for the organism. Recent research has suggested that the parts of the transcription factors that are not structurally defined in solution, so called intrinsically disordered regions (IDRs), have a higher potential for evolutionary diversification than more structurally rigid regions. This suggests that these domains that earlier have been considered mostly unimportant may have an important potential for evolutionary diversification. This project aimed to further evaluate evidence supporting the hypothesis that variable-structured domains in transcription factors are of significant importance for functional diversification. This was be done by comparing the rate of synonymous and non-synonymous genetic variation in the coding regions of 12 selected TFs within a highly conserved clade of European wine yeasts and by comparing this variation to divergent phenotypic patterns within the strains. The frequency of non-synonymous mutations was much greater than for synonymous mutations indicating an important role of positive selection acting on these TFs during diversification of the different strains. No significant connections were discovered between the distribution of DNA variation and phenotypic patterns.

  • 115.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    A Missing Pillar? Challenges in theorizing and practicing social sustainability: introductory article in the special issue2012Ingår i: Sustainability: Science, Practice, & Policy, ISSN 1548-7733, E-ISSN 1548-7733, Vol. 8, nr 1, s. 3-14Artikel i tidskrift (Refereegranskat)
  • 116.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Hybridorganisationer2009Ingår i: Från klass till organisation: En resa genom det sociala landskapet / [ed] Roman, Christine & Udéhn, Lars, Malnö: Liber , 2009, s. 170-189Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 117.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    [Recension av] Ellen Ruppel Shell (2009) Cheap, The High Cost of Discount Culture, New York: The Penguin Press2010Ingår i: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 14, nr 1, s. 174-176Artikel, recension (Övrigt vetenskapligt)
  • 118.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    The challenges in achieving the “social” dimension of sustainable development.: The case of the Forest Stewardship Council2010Rapport (Övrigt vetenskapligt)
  • 119.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper.
    The Historical and Contemporary Roles of Nature Protection Organisations in Sweden2007Ingår i: Protecting Nature: Organizations and networks in Europe and the USA / [ed] C.S.A (Kris) van Koppen & William T. Markham, Cheltenham: Edward Elgar , 2007, s. 213-238Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 120.
    Boström, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    The Problematic Social Dimension of Sustainable Development: the Case of the Forest Stewardship Council2012Ingår i: International Journal of Sustainable Development and World Ecology, ISSN 1350-4509, E-ISSN 1745-2627, Vol. 19, nr 1, s. 3-15Artikel i tidskrift (Refereegranskat)
  • 121.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Börjeson, Natasja
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Gilek, Michael
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Jönsson, Anna Maria
    Södertörns högskola, Institutionen för kultur och kommunikation, Medie- och kommunikationsvetenskap.
    Karlsson, Mikael
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Responsible procurement and complex product chains: the case of chemical risks in textiles2012Ingår i: Journal of Environmental Planning and Management, ISSN 0964-0568, E-ISSN 1360-0559, Vol. 55, nr 1, s. 95-111Artikel i tidskrift (Refereegranskat)
  • 122.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Börjeson, Natasja
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Gilek, Michael
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Jönsson, Anna Maria
    Södertörns högskola, Institutionen för kultur och kommunikation, Medie- och kommunikationsvetenskap.
    Karlsson, Mikael
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Towards responsible procurement in relation to chemical risks in textiles?: Findings from an interview study2011Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In the present study, we ask whether and how different organizations work with sustainable procurement and how this work relates to the complexity of the product chain. We have chosen to focus on chemical risks in relation to textiles – an issue that increasingly is becoming part of the public discourse and a target for journalists. In the case of textiles, the product chain from raw material to consumption often involves a great number of production steps, sub-contractors and users, often on a global scale. Sustainable management of the supply chain would improve health, quality of life, and labour conditions, for instance in the areas and factories in developing countries where production and processing often take place. However, such management faces great difficulties and challenges in terms of capabilities, knowledge, communication, and policy instruments. These difficulties are related to high uncertainties and other problems that in turn are related to the high complexity of global product chains. The objective of the present report is to gain insights into the opportunities and challenges that private and public organizations face regarding the development of responsible procurement in relation to a complex and uncertain issue. The report focuses on chemicals in textiles and uses a qualitative methodology with semi-structured interviews. Key elements of a pro-active, responsible procurement strategy are defined in the report and include criteria such as using a preventive, systematic, responsive, integrative, and reflective approach. The analysis includes the following topics: (i) priorities and knowledge, (ii) communicative strategies, (iii) policy instruments, (iv) monitoring and trust in relation to suppliers. The results show a fairly modest level of organizational responsibility, although it is possible to observe an initial positive development among the cases investigated. The report ends by suggesting a number of topics that require further investigation.

  • 123.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Garsten, Christina
    Organizing for accountability2008Ingår i: Organizing Transnational Accountability / [ed] Boström, Magnus & Garsten, Christina, Cheltenham: Edward Elgar , 2008, s. 1-26Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 124.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Garsten, Christina
    Organizing Transnational Accountability2008Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
  • 125.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Garsten, Christina
    The treadmill of accountability2008Ingår i: Organizing Transnational Accountability / [ed] Boström, Magnus & Garsten, Christina, Cheltenham: Edward Elgar Publishing, 2008, s. 231-249Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 126.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Klintman, Mikael
    Eco-standards, product labelling and green consumerism2008Bok (Övrigt vetenskapligt)
  • 127.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Klintman, Mikael
    The green political consumer of food: A critical analysis of the research and policies2009Ingår i: Anthropology of Food, ISSN 1609-9168, E-ISSN 1609-9168, nr Sept.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper reviews the current literature on political and ethical consumers, and relates it to the topic of sustainable food consumption. A first aim is to problematise a somewhat simplistic view of the political and ethical consumer found in the literature. The paper sheds light on some of the dilemmas that confront green political consumers. We indicate that most existing studies say very little about consumers’ thoughts, assumptions, and reflections about green consumerism in general, and about green consumerist tools, such as green labels, more specifically. Based on a literature review, we draw a picture of the typical concerned consumer as reflective, uncertain and ambivalent. This is connected to a second aim of the paper: to discuss a gap or mismatch between the production side and consumption side of green (food) labels. We conclude the paper by suggesting that green and ethical information schemes could become much more in line with the reflective nature of green, political consumers. We relate this discussion to concepts such as sub-politics and meta-politics.

  • 128.
    Boström, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Tamm Hallström, Kristina
    NGO power in global social and environmental standard setting2010Ingår i: Global Environmental Politics, ISSN 1526-3800, E-ISSN 1536-0091, Vol. 10, nr 4, s. 36-59Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have seen a worldwide increase in new nonstate, multi-stakeholder organizations setting standards for socially and environmentally responsible behavior. These standard-setting arenas offer new channels for political participation for NGOs. Scholars have drawn attention to the rise and the role of NGOs in global politics, but there is less research on the power and long-term implications of NGO participation in transnational multi-stakeholder standard-setting. This article analyzes NGOs within three such global organizations: the Forest Stewardship Council, the Marine Stewardship Council, and the International Organization for Standardization on Social Responsibility. Using a power-based perspective, we demonstrate the impact that NGOs can have on multi-stakeholder work. In doing so, we analyze four types of NGO power: symbolic, cognitive, social, and monitoring power. The article further emphasizes institutional, structural, and discursive factors within multi-stakeholder organizations that create certain challenges to NGO power and participation in the longer term.

  • 129. Bratic, Ivana
    et al.
    Hench, Jürgen
    Södertörns högskola, Institutionen för livsvetenskaper.
    Henriksson, Johan
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Antebi, Adam
    Bürglin, Thomas R.
    Trifunovic, Aleksandra
    Mitochondrial DNA level, but not active replicase, is essential for Caenorhabditis elegans development2009Ingår i: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 37, nr 6, s. 1817-1828Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A number of studies showed that the development and the lifespan of Caenorhabditis elegans is dependent on mitochondrial function. In this study, we addressed the role of mitochondrial DNA levels and mtDNA maintenance in development of C. elegans by analyzing deletion mutants for mitochondrial polymerase gamma (polg-1(ok1548)). Surprisingly, even though previous studies in other model organisms showed necessity of polymerase gamma for embryonic development, homozygous polg-1(ok1548) mutants had normal development and reached adulthood without any morphological defects. However, polg-1 deficient animals have a seriously compromised gonadal function as a result of severe mitochondrial depletion, leading to sterility and shortened lifespan. Our results indicate that the gonad is the primary site of mtDNA replication, whilst the mtDNA of adult somatic tissues mainly stems from the developing embryo. Furthermore, we show that the mtDNA copy number shows great plasticity as it can be almost tripled as a response to the environmental stimuli. Finally, we show that the mtDNA copy number is an essential limiting factor for the worm development and therefore, a number of mechanisms set to maintain mtDNA levels exist, ensuring a normal development of C. elegans even in the absence of the mitochondrial replicase.

  • 130.
    Breivik, Moa
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    En utvärdering av Länsstyrelsen i Jämtlands läns uppföljning av den hotade orkidén brunkulla2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Det har skett en stor förändring inom det svenska jordbruket det senaste seklet, traditionell slåtter och beteshävd har nästan upphört helt. Förändrad markanvändning orsakar habitatförlust för många växter och djur. Slåtter och betesmarkerna som hör till de artrikaste växtsamhällena i Sverige hotas av igenväxning. I denna uppsats studerar jag Länsstyrelsen i Jämtlands läns uppföljning av den starkt hotade orkidén brunkulla (Gymnadenia nigra) som är en hävdgynnad art på tillbakagång. Studien baseras på intervjuer med anställda på Länsstyrelsen i Jämtlands län samt de inventeringsdata man samlat inom uppföljningen. Jag har utvärderat om resultaten från Länsstyrelsens uppföljning uppfyller det syfte som inventeringarna ursprungligen hade. Jag har studerat inventeringsdata och analyserat metodiken i relation till vetenskapliga rekommendationer samt genomfört statistiska tester. Jag har funnit att nuvarande uppföljning har brustit i genomförandet samt i anpassningen av inventeringsmetodiken mot inventeringarnas syfte. I kombination med den hitintills korta mätperioden har detta resulterat i att ingen populationstrend kunnat utläsas och att effekter av hävd och andra miljövariabler inte kan utvärderas på ett tillfredställande sätt.

  • 131.
    Briones Dahlin, Antonio
    Södertörns högskola, Institutionen för livsvetenskaper.
    Botanical pesticides: a part of sustainable agriculture in Babati District Tanzania2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Botanical pesticides are agricultural pest management agents which are based on plant extracts. In modern times these have been used as alternatives to synthetic chemicals in organic pest management. The practice of using plant materials against field and storage pests however has a long history in many indigenous and traditional farming communities across the world. During February and March 2009 a field study was conducted in Babati district in Manyara region, Tanzania to investigate the local use of botanical pesticides. The results from the field study were subsequently analyzed and contextualized in Nicanor Perlas model The Seven Dimensions of Sustainable Agriculture which was used as a framework theory. The analysis indicates that there are a variety of thresholds for the use of botanical pesticides in sustainable agriculture in Babati district besides the more obvious practical aspects. The latter parts of the paper discuss the differences between reductionist and holistic, indigenous and scientific ways of achieving knowledge with regard to plant based pesticides. The study concludes that ecological pest management is a holistic method based on the synergy of a variety of farming practices. Indigenous knowledge which is holistic, site-specific and experience based has therefore much to offer modern endeavours to practice a more sustainable agriculture and pest management strategies which consider the welfare of both humanity and the environment.

  • 132.
    Broniarczyk, Justyna
    et al.
    Department of Molecular Virology, Adam Mickiewicz University.
    Wigerius, Michael
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Södertörns högskola, Institutionen för livsvetenskaper, Kemi.
    Johansson, Magnus
    Södertörns högskola, Institutionen för livsvetenskaper, Internationell hälsa. Södertörns högskola, Institutionen för livsvetenskaper, Kemi.
    The NS1 protein of Influenza A virus targets human Scribble in asubtype specific mannerManuskript (preprint) (Övrigt vetenskapligt)
  • 133.
    Browall, Sarah
    Södertörns högskola, Institutionen för livsvetenskaper.
    Comparative genomic analyse by microarray technology of pneumococci with different potential to cause disease.2007Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    Streptococcus pneumoniae is a gram-positive bacterium that can be found in both healthy carriers as well as in people that have developed disease. One of the major virulence factors of pneumococci is their polysaccharide capsule. Based on the capsule that surrounds the bacteria, pneumococci are divided into at least 90 different serotypes. Some serotypes seem to be more related to virulence than others.

    I have with comparative genome hybridization microarray technique, studied gene differences between 18 epidemiological well-characterised pneumococcal strains with different potential to cause disease. A microarray chip based on two sequenced pneumococcal genomes, R6 and TIGR4, has already been designed. According to Hierarchical clustering, both the serotype and the genetic type as assessed by MLST (sequence type or ST) seem to have impact on the relationship of clinical isolates. Most clinical isolates of the same serotype are clustered together except for serotype 14 isolates that seem to be more divergent. Further more the number of genes that are divergent between clinical isolates compared to R6 and TIGR4 differ from 65 to 289. Preliminary results indicate that although there is diversity among clinical isolates some are more closely related to each other then others. Absent genes seem to be evenly distributed among all 18 clinical isolates tested but hypothetical genes and genes for cell envelope are two groups of role categories that are absent to the largest extent in all isolates.

    According to results from microarray analysis, a gene region, spr0112-spr1015- is present in all type 9V isolates and absent in many isolates of serotype 14, 19F and 7F. These results have been confirmed by polymerase chain reaction (PCR).

    Conserved genes in a region around the capsule genes have been sequenced to identify marker genes for a capsulular switch between serotype 9V and 14. Preliminary results of the sequencing showed that as much as 750kb might have been transferred in the event of capsular switch.

  • 134. Bränn, Kristina Holmen
    et al.
    Lehtilä, Kari
    Södertörns högskola, Institutionen för livsvetenskaper.
    Maternal plant responses to high pollen loads2007Ingår i: International journal of plant sciences, ISSN 1058-5893, E-ISSN 1537-5315, Vol. 168, nr 7, s. 1013-1019Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Maternal plant responses to different levels of pollination vary and are of importance for the total fitness of the plant. We studied how varying pollen load affects late flowering, reproduction, and growth of maternal plants. Raphanus raphanistrum, Sinapis arvensis, and Brassica napus were used as study species. We conducted hand- pollination experiments with different pollen loads for early flowers in the inflorescence and measured responses on vegetative traits, floral traits of late flowers, and seed production. There were no effects on vegetative traits, but floral traits were affected by treatments in two of the study species. The high pollen load treatment in S. arvensis resulted in longer petals on late flowers compared with the low pollen load treatment. In R. raphanistrum, the high pollen load treatment resulted in a higher number of flowers, with narrower petals, than the low pollen load treatment. Total seed production was similar in both treatments in all species. Our results suggest that plants that received a high pollen load were able to allocate resources to high seed production of early flowers and to increased pollen dispersal of late flowers, thereby achieving higher total fitness than plants that received a lower pollen load.

  • 135.
    Bräutigam, Lars
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Hillmer, Janine M.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Söll, Iris
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Hauptmann, Giselbert
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Localized Expression of Urocortin Genes in the Developing Zebrafish rain2010Ingår i: Journal of Comparative Neurology, ISSN 0021-9967, E-ISSN 1096-9861, Vol. 518, nr 15, s. 2978-2995Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The corticotropin-releasing hormone (CRH) family consists of four aralogous genes, CRH and urocortins (UCNs) 1, 2, and 3. In a previous tudy, we analyzed CRH in the teleost model organism zebrafish and its ranscript distribution in the embryonic brain. Here, we describe ull-length cDNAs encoding urotensin 1 (UTS1), the teleost UCN1 rtholog, and UCN3 of zebrafish. Major expression sites of uts1 in adult ebrafish are the caudal neurosecretory system and brain. By using T-PCR analysis, we show that uts1 mRNA is also present in ovary, aternally contributed to the embryo, and expressed throughout embryonic evelopment. Expression of ucn3 mRNA was detected in a range of adult issues and during developmental stages from 24 hours post fertilization nward. Analysis of spatial transcript distributions by whole-mount in itu hybridization revealed limited forebrain expression of uts1 and cn3 during early development. Small numbers of uts1-synthesizing eurons were found in subpallium, hypothalamus, and posterior iencephalon, whereas ucn3-positive cells were restricted to elencephalon and retina. The brainstem was the main site of uts1 and cn3 synthesis in the embryonic brain. uts1 Expression was confined to he midbrain tegmentum; distinct hindbrain cell groups, including locus oeruleus and Mauthner neurons; and the spinal cord. ucn3 Expression was ocalized to the optic tectum, serotonergic raphe, and distinct hombomeric cell clusters. The prominent expression of uts1 and ucn3 in rainstem is consistent with proposed roles of CRH-related peptides in tress-induced modulation of locomotor activity through monoaminergic rainstem neuromodulatory systems. J. Comp. Neurol. 518:2978-2995, 2010.

  • 136.
    Buch, Charlotta
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Dynamic protein trafficking of the nuclear membrane and in peroxisomes2009Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The cell nucleus is enclosed by the nuclear envelope (NE), a double lipid membrane separating the nucleoplasm from the cytoplasm. Transport of macromolecules between the nucleus and the cytoplasm takes places through nuclear pore complexes (NPCs) in a selective and energy dependent manner. The inner nuclear membrane (INM) contains transmembrane proteins that interact with the nuclear lamina and chromatin. In addition to being a barrier between the nucleoplasm and cytoplasm, an emerging view is that the NE has an active role in chromatin organization and gene regulation.

    In order to study structural and functional organization of the NE in live cells, we have used green fluorescent protein (GFP)-labeled proteins and laser scanning confocal microscopy (LSCM). In order to investigate dynamic properties of specific proteins or protein complexes we have used photobleaching techniques. In order to understand the organization of the NPC it is essential to study components necessary for NPC biogenesis and maintenance. We have investigated the possible alterations in the NPC in cells naturally lacking one of the integral membrane proteins of the NPC, gp210. Despite the lack of gp210, we observed no difference in distribution or density of pores. Neither did cell cycle progression nor generation time differ between cells having or lacking gp210. In addition, targeting or dynamic properties of the NPC proteins POM121, Nup107 or Nup153 were unaltered in the absence of gp210. We conclude that gp210 can not be essential for NPC biogenesis or maintaining stability of the NPC.

    The steps involved in onset of nuclear apoptosis are unclear. We studied nuclear alterations during apoptosis. We show that the nucleocytoplasmic barrier is disrupted early in apoptosis at the same time as chromatin collapses against the nuclear periphery but prior to nucleosomal DNA fragmentation. In addition, the disruption of nucleocytoplasmic transport correlates with caspase-3 dependent cleavage of POM121 at aspartate-531.

    The INM is estimated to contain ~70 uncharacterized transmembrane proteins. We characterized a novel putative mammalian NE protein that we termed Samp1. We show that Samp1 is an integral membrane protein specifically localized to the inner nuclear membrane during interphase. Interestingly, during mitosis a sub fraction of Samp1 distributed in the polar region of the mitotic spindle, colocalizing with tubulin and a lipid marker. However, another inner nuclear membrane protein, emerin, was excluded from this area. Thus Samp1 appears to define a specific membrane domain associated with the mitotic machinery.

    The distribution of peroxisomal fatty acid metabolizing enzymes have been reported to vary in different tissues. We investigated whether photobleaching techniques could be used to study the distribution of peroxisomal matrix proteins. We used GFP-labeled peroxisomal proteins and fluorescence recovery after photobleaching to show that peroxisomal matrix proteins become “trapped” inside peroxisomes after import. Thus we conclude that fluorescence loss in photobleaching can be used to distinguish between a strictly cytoplasmic localization and a dual localization when a protein is present both in the cytoplasm and in peroxisomes. Using this technique we determined that GFP-BAAT (bile acid-CoA:amino acid N-acyltransferase) is exclusively localized to the cytoplasm in HeLa cells.

  • 137.
    Buch, Charlotta
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Hunt, Mary C.
    Alexson, Stefan E. H.
    Hallberg, Einar
    Södertörns högskola, Institutionen för livsvetenskaper.
    Localization of peroxisomal matrix proteins by photobleaching2009Ingår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 388, nr 2, s. 355-359Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The distribution of some enzymes between peroxisomes and cytosol, or a dual localization in both these compartments, can be difficult to reconcile. We have used photobleaching in live cells expressing green fluorescent protein (GFP)-fusion proteins to show that imported bona fide peroxisomal matrix proteins are retained in the peroxisome. The high mobility of the GFP-fusion proteins in the cytosol and absence of peroxisomal escape makes it possible to eliminate the cytosolic fluorescence by photobleaching, to distinguish between exclusively cytosolic proteins and proteins that are also present at low levels in peroxisomes. Using this technique we found that GFP tagged bile acid-CoA:amino acid N-acyltransferase (BAAT) was exclusively localized in the cytosol in HeLa cells. We conclude that the cytosolic localization was due to its carboxyterminal non-consensus peroxisomal targeting signal (-SQL) since mutation of the -SQL to -SKL resulted in BAAT being efficiently imported into peroxisomes.

  • 138.
    Buch, Charlotta
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Lindberg, Robert
    Södertörns högskola, Institutionen för livsvetenskaper.
    Figueroa, Ricardo
    Södertörns högskola, Institutionen för livsvetenskaper.
    Gudise, Santhosh
    Södertörns högskola, Institutionen för livsvetenskaper.
    Onischenko, Evgeny
    Hallberg, Einar
    Södertörns högskola, Institutionen för livsvetenskaper.
    An integral protein of the inner nuclear membrane localizes to the mitotic spindle in mammalian cells2009Ingår i: Journal of Cell Science, ISSN 0021-9533, E-ISSN 1477-9137, Vol. 122, nr 12, s. 2100-2107Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here, we characterize a transmembrane protein of the nuclear envelope that we name spindle-associated membrane protein 1 (Samp1). The protein is conserved in metazoa and fission yeast and is homologous to Net5 in rat and Ima1 in Schizosaccharomyces pombe. We show that, in human cells, the protein is a membrane-spanning polypeptide with an apparent molecular mass of 43 kDa. This is consistent with a predicted polypeptide of 392 amino acids that has five transmembrane segments and its C-terminus exposed to the nucleoplasm. During interphase, Samp1 was specifically distributed in the inner nuclear membrane. Post-transcriptional silencing of Samp1 expression resulted in separation of centrosomes from the nuclear envelope, indicating that it is functionally connected to the cytoskeleton. At the onset of mitosis, most of the protein dispersed out into the ER, as expected. However, during mitosis, a significant fraction of the protein specifically localized to the polar regions of the mitotic spindle. We demonstrate for the first time, in human cells, the existence of a membranous structure overlapping with the mitotic spindle. Interestingly, another integral inner nuclear membrane protein, emerin, was absent from the spindle-associated membranes. Thus, Samp1 defines a specific membrane domain associated with the mitotic spindle.

  • 139.
    Burström, Annika
    Södertörns högskola, Institutionen för livsvetenskaper.
    Have the Tsetse Clearings in the Babati District, Tanzania, Influenced the Spread of Agriculture Land?2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The clearing of woodland to eradicate the tsetse fly in the Babati district, Tanzania, was a governmental initiative. The clearings were mainly carried out in the mid 20th century and managed to reduce the tsetse fly by a great amount. The clearings opened up remote areas and made it possible to access areas that had previously been unavailable for humans. The clearing also had an enormous impact on the environment. This is a case study on five different areas in the Babati district that have all been subjected to tsetse clearings. The studied areas are Bonga, Kiru Erri Kiru Valley, Magugu and Mamire.

    The fieldwork consisted of semi-structured interviews and transect walks. The purpose was to study if the clearings have had any influence over the spreading of agriculture land that were not cultivated before and to inquire into the most significant environmental impact that the clearings had.

    Different outcome in agriculture land spreading due to the clearings could be seen in the five studied areas. In Bonga and Kiru Valley no agriculture started after the clearings, but in Kiru Erri, Magugu and Mamire some of cleared land is nowadays used for agriculture. The result of the fieldwork indicates that the clearings have had noticeable influence over the spreading of agriculture land but there were also other important driving forces. These were increase in population, land degradation, land shortages and the politic agenda. The most important negative environmental impact due to the clearings was erosion.

  • 140.
    Bylund, Louise
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Degernäs, Elinor
    Södertörns högskola, Institutionen för livsvetenskaper.
    Öberg, Anna
    Södertörns högskola, Institutionen för livsvetenskaper.
    Professionalisering av möten: En studie om hur möten som kommunikationsverktyg kan gynna företag och mötesindustrin2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna kvalitativa uppsats belyser problematiken kring företagens bristande kunskap om mötens betydelse för företagsutveckling. Flera av de möten som genomförs idag saknar ett genomarbetat syfte och mål. Detta har lett till att mötesindustrin sakta börjar bli införstådd i att företagen har ett behov av professionell hjälp med utformningen av möten. De möten som genomförs ska vara utvecklande för både företaget och medarbetarna. Företag bör komma till insikt om mötens vikt, genom att använda möten som ett kommunikationsverktyg kan mötets fulla kapacitet utnyttjas. När företag genomför möten ska fokus ligga på kvalitén i mötet, snarare än kostnaden. Möten bör ses som en investering på samma sätt som en investering av en fysisk produkt. Det nya sättet att planera och genomföra möten tror vi är en ny inriktning inom mötesindustrin. Denna inriktning fokuserar på en professionalisering av mötets innehåll och syfte. Denna utveckling kommer att gynna företag både inom och utanför mötesindustrin. Företag utanför mötesindustrin kommer med en professionalisering att ersätta många ineffektiva möten med färre men effektivare möten. Det professionella mötet ska användas som ett verktyg för att nå framgång, konkurrensföredelar och utveckling. Mötesindustrin gynnas av denna utveckling då fler företag vill anlita professionell hjälp, vilket bidrar till en ny inriktning med nya tjänster som kan generera i en högre omsättning.

  • 141.
    Böhme, Jan
    Södertörns högskola, Institutionen för livsvetenskaper.
    Den naturvetenskapliga textens utveckling : då, nu och sedan – med en avstickare också till människans utveckling2009Ingår i: En bok om böcker och bibliotek: tillägnad Louise Brunes, Huddinge: Södertörns högskola , 2009, s. 155-171Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 142.
    Börjeson, Natasja
    Södertörns högskola, Institutionen för livsvetenskaper.
    Coffee is money, maize is food: Discussing agricultural specialization in Tanzania2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    This paper deals with the economic development of Tanzania and especially with the development of the smallholders. My aim is to study whether the Structural Adjustment Programmes have helped to facilitate growth in the agricultural and export-sector and if the reforms implemented through the programmes have made agricultural specialization easier and improved the economic situation for the smallholders.

    In this paper, I will discuss that there might be significant limitations in the favours received due to SAP and that the Structural Adjustment Programmes because of this may not be the model for agricultural development as it is claimed by the initiators; the World Bank and the IMF. On the contrary, I present the idea that SAP can be said to have failed in its undertaking and that the reforms might not be suitable for the smallholder sector. I will in the paper argue that SAP has not facilitated an agricultural specialization and that this has much to do with the increase of production costs that the smallholders have been faced with after the reforms. And because of this it could be argued that the Structural Adjustment Programmes might not be an appropriate development strategy for Tanzania, if the country is to achieve growth through specialization. Consequently, there might be reason to believe that the reforms not are overall suitable for the Tanzanian development, considering that a growth within the agricultural smallholder sector is crucial for Tanzania to achieve a long term economic growth.

  • 143.
    Börjeson, Natasja
    Södertörns högskola, Institutionen för livsvetenskaper.
    WTO, GMO and the precautionary principle: the conflict between trade liberalisation and environmental protection2007Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    This study examines the possible incompatibility between environmental conventions and agreements promoting international trade. More specifically, it aims at discussing the Precautionary Principle and the WTO agreements on trade and how they might contradict each other on the international arena. The study focuses on the international trade with genetically modified organisms and discusses probable needs of reformulating the principles and/or conventions concerned if these are to function as tools of equal importance when handling environmental problems through policy making. The controversy is illustrated through a case-study of a trade dispute where the conflicting principles: the Precautionary Principle and WTO agreements on trade are involved, namely a dispute where a formal complaint to the WTO by the US, Canada and Argentina about the European Community supposedly applying a de facto moratorium on genetically modified organisms had the final outcome of the European Community being found to contravene international trade rules. The study concludes that actors on the international arena are still opinions apart concerning the way to perceive possible risks connected to biotechnology and genetically modified organisms. This incongruence is also found to apply to the status of the Precautionary Principle as a rule of international law as well as to which of the conventions that were applicable to the concerned dispute.

  • 144.
    Börjesson, Christine
    Södertörns högskola, Institutionen för livsvetenskaper.
    Gender policy implementation - basic ideas and effects.: A study of Sida's gender policy and its relation to gender equality in Babati District, Tanzania2005Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats
    Abstract [en]

    This study have two purposes, one is to examine the ideological consistency between Sida’s gender policy and the gender policy of an implemented project, and the other purpose consists of an attempt to identify a relation between the implementation of Sida’s/LAMP’s policies and actual changes on gender equality in the partnering country. Three research questions were formulated around the topics of women’s situation in Tanzania; the ideological origin of Sida’s gender policy and the reflection of these in the LAMP policy; and the consequences of an implementation in terms of equality between men and women in Babati District, Tanzania. The analysis is carried out with the help of different theoretical perspectives on women and gender in development, perspectives that have been selected on the basis that they have been influential and dominating in the contemporary planning and policy making of development agencies. The method used was a functional idea analysis and a field study where semi-structured interviews were conducted. The conclusion regarding the ideological consistency is that a comparison between the policies of Sida and LAMP shows patterns of great ideological resemblance, and that both have a somewhat stronger connection to the GAD approach. The conclusion regarding actual changes on gender equality reveals that an integration of gender aspects into the LAMP programme has had several consequences for women. The programme has helped to reduce women’s work load, increased their chances of income, and promoted women’s participation in decision-making on different levels. These are all aspects that may challenge the traditional order of women’s relationship to men and the subordination of women.

  • 145.
    Bürglin, Thomas R.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Evolution of hedgehog and hedgehog-related genes, their origin from Hog proteins in ancestral eukaryotes and discovery of a novel Hint motif2008Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 9, s. 127-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The Hedgehog (Hh) signaling pathway plays important roles in human and animal development as well as in carcinogenesis. Hh molecules have been found in both protostomes and deuterostomes, but curiously the nematode Caenorhabditis elegans lacks a bona-fide Hh. Instead a series of Hh-related proteins are found, which share the Hint/Hog domain with Hh, but have distinct N-termini. Results: We performed extensive genome searches such as the cnidarian Nematostella vectensis and several nematodes to gain further insights into Hh evolution. We found six genes in N. vectensis with a relationship to Hh: two Hh genes, one gene with a Hh N-terminal domain fused to a Willebrand factor type A domain (VWA), and three genes containing Hint/Hog domains with distinct novel N-termini. In the nematode Brugia malayi we find the same types of hh-related genes as in C. elegans. In the more distantly related Enoplea nematodes Xiphinema and Trichinella spiralis we find a bona-fide Hh. In addition, T. spiralis also has a quahog gene like C. elegans, and there are several additional hh-related genes, some of which have secreted N-terminal domains of only 15 to 25 residues. Examination of other Hh pathway components revealed that T. spiralis - like C. elegans - lacks some of these components. Extending our search to all eukaryotes, we recovered genes containing a Hog domain similar to Hh from many different groups of protists. In addition, we identified a novel Hint gene family present in many eukaryote groups that encodes a VWA domain fused to a distinct Hint domain we call Vint. Further members of a poorly characterized Hint family were also retrieved from bacteria. Conclusion: In Cnidaria and nematodes the evolution of hh genes occurred in parallel to the evolution of other genes that contain a Hog domain but have different N-termini. The fact that Hog genes comprising a secreted N-terminus and a Hog domain are found in many protists indicates that this gene family must have arisen in very early eukaryotic evolution, and gave rise eventually to hh and hh-related genes in animals. The results indicate a hitherto unsuspected ability of Hog domain encoding genes to evolve new N-termini. In one instance in Cnidaria, the Hh N-terminal signaling domain is associated with a VWA domain and lacks a Hog domain, suggesting a modular mode of evolution also for the N-terminal domain. The Hog domain proteins, the inteins and VWA-Vint proteins are three families of Hint domain proteins that evolved in parallel in eukaryotes.

  • 146.
    Bürglin, Thomas R.
    Södertörns högskola, Institutionen för livsvetenskaper.
    The Hedgehog protein family2008Ingår i: Genome Biology, ISSN 1465-6906, E-ISSN 1474-760X, Vol. 9, nr 11, s. 241-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Hedgehog (Hh) pathway is one of the fundamental signal transduction pathways in animal development and is also involved in stem-cell maintenance and carcinogenesis. The hedgehog (hh) gene was first discovered in Drosophila, and members of the family have since been found in most metazoa. Hh proteins are composed of two domains, an amino-terminal domain HhN, which has the biological signal activity, and a carboxy-terminal autocatalytic domain HhC, which cleaves Hh into two parts in an intramolecular reaction and adds a cholesterol moiety to HhN. HhC has sequence similarity to the self-splicing inteins, and the shared region is termed Hint. New classes of proteins containing the Hint domain have been discovered recently in bacteria and eukaryotes, and the Hog class, of which Hh proteins comprise one family, is widespread throughout eukaryotes. The non-Hh Hog proteins have carboxy-terminal domains ( the Hog domain) highly similar to HhC, although they lack the HhN domain, and instead have other amino-terminal domains. Hog proteins are found in many protists, but the Hh family emerged only in early metazoan evolution. HhN is modified by cholesterol at its carboxyl terminus and by palmitate at its amino terminus in both flies and mammals. The modified HhN is released from the cell and travels through the extracellular space. On binding its receptor Patched, it relieves the inhibition that Patched exerts on Smoothened, a G-protein-coupled receptor. The resulting signaling cascade converges on the transcription factor Cubitus interruptus (Ci), or its mammalian counterparts, the Gli proteins, which activate or repress target genes.

  • 147.
    Bürglin, Thomas R.
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institute.
    Kuwabara, P. E.
    Homologs of the Hh signalling network in C. elegans2006Ingår i: WormBook : the online review of C. elegans biology, ISSN 1551-8507, s. 1-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In Drosophila and vertebrates, Hedgehog (Hh) signalling is mediated by a cascade of genes, which play essential roles in cell proliferation and survival, and in patterning of the embryo, limb buds and organs. In C. elegans, this pathway has undergone considerable evolutionary divergence; genes encoding homologues of key pathway members, including Hh, Smoothened, Cos2, Fused and Suppressor of Fused, are absent. Surprisingly, over sixty proteins (i.e. WRT, GRD, GRL, and QUA), encoded by a set of genes collectively referred to as the Hh-related genes, and two co-orthologs (PTC-1,-3) of fly Patched, a Hh receptor, are present in C. elegans. Several of the Hh-related proteins are bipartite and all can potentially generate peptides with signalling activity, although none of these peptides shares obvious sequence similarity with Hh. In addition, the ptc-related (ptr) genes, which are present in a single copy in Drosophila and vertebrates and encode proteins closely related to Patched, have undergone an expansion in number in nematodes. A number of functions, including roles in molting, have been attributed to the C. elegans Hh-related, PTC and PTR proteins; most of these functions involve processes that are associated with the trafficking of proteins, sterols or sterol-modified proteins. Genes encoding other components of the Hh signalling pathway are also found in C. elegans, but their functions remain to be elucidated.

  • 148. Caballero-Herrera, A
    et al.
    Nordstrand, Kerstin
    Södertörns högskola, Institutionen för livsvetenskaper.
    Berndt, Kurt D
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Nilsson, L
    Effect of urea on peptide conformation in water: Molecular dynamics and experimental characterization2005Ingår i: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 89, nr 2, s. 842-857Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Molecular dynamics simulations of a ribonuclease A C-peptide analog and a sequence variant were performed in water at 277 and 300 K and in 8 M urea to clarify the molecular denaturation mechanism induced by urea and the early events in protein unfolding. Spectroscopic characterization of the peptides showed that the C-peptide analog had a high alpha-helical content, which was not the case for the variant. In the simulations, interdependent side-chain interactions were responsible for the high stability of the alpha-helical C-peptide analog in the different solvents. The other peptide displayed alpha-helical unwinding that propagated cooperatively toward the N-terminal. The conformations sampled by the peptides depended on their sequence and on the solvent. The ability of water molecules to form hydrogen bonds to the peptide as well as the hydrogen bond lifetimes increased in the presence of urea, whereas water mobility was reduced near the peptide. Urea accumulated in excess around the peptide, to which it formed long-lived hydrogen bonds. The unfolding mechanisms induced by thermal denaturation and by urea are of a different nature, with urea-aqueous solutions providing a better peptide solvation than pure water. Our results suggest that the effect of urea on the chemical denaturation process involves both the direct and indirect mechanisms.

  • 149.
    Calero, Martina
    Södertörns högskola, Institutionen för livsvetenskaper.
    Kulturproduktion och makt: En intersektionell analys av candombespelande kvinnor i Uruguay2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This is a study of the way power relationships change when women start to play candombe in Montevideo, Uruguay. Candombe is a type of music, which is traditionally played by men within the black minority in the country. This study has been done with an intersectional point of view, taking the social categories gender, class and ethnicity in account. The method used was participatory observation in a field study made in Montevideo between November 2008 and February 2009.

    This study’s main conclusions are that the power relationships change with the participation of women in candombe in several important ways: The women legitimize an alternative way to be a woman when they take the men’s role as a drum player. Hegemonic relationships are made visible. The men’s privileged position within candombe is questioned. Hegemonic ideas of ethnicity and class are in some way challenged since candombe is a space where categories with low status may gain respect from society. However, there is a risk that “the social norm” outlines a framework for what is accepted and approved within candombe, and what is not. It is therefore crucial that the players in candombe define its meaning themselves.

  • 150. Cao, Renhai
    et al.
    Jensen, Lasse Dahl Ejby
    Söll, Iris
    Södertörns högskola, Institutionen för livsvetenskaper.
    Hauptmann, Giselbert
    Södertörns högskola, Institutionen för livsvetenskaper.
    Cao, Yihai
    Hypoxia-Induced Retinal Angiogenesis in Zebrafish as a Model to Study Retinopathy2008Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 3, nr 7, s. e2748-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mechanistic understanding and defining novel therapeutic targets of diabetic retinopathy and age-related macular degeneration (AMD) have been hampered by a lack of appropriate adult animal models. Here we describe a simple and highly reproducible adult fli-EGFP transgenic zebrafish model to study retinal angiogenesis. The retinal vasculature in the adult zebrafish is highly organized and hypoxia-induced neovascularization occurs in a predictable area of capillary plexuses. New retinal vessels and vascular sprouts can be accurately measured and quantified. Orally active anti-VEGF agents including sunitinib and ZM323881 effectively block hypoxia-induced retinal neovascularization. Intriguingly, blockage of the Notch signaling pathway by the inhibitor DAPT under hypoxia, results in a high density of arterial sprouting in all optical arteries. The Notch suppression-induced arterial sprouting is dependent on tissue hypoxia. However, in the presence of DAPT substantial endothelial tip cell formation was detected only in optic capillary plexuses under normoxia. These findings suggest that hypoxia shifts the vascular targets of Notch inhibitors. Our findings for the first time show a clinically relevant retinal angiogenesis model in adult zebrafish, which might serve as a platform for studying mechanisms of retinal angiogenesis, for defining novel therapeutic targets, and for screening of novel antiangiogenic drugs.

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