993 resultados para 02240416 TM-7
Resumo:
Tämän tutkimuksen tarkoitus on selvittää millainen suhde käsitteiden ”aktiivinen” ja ”kontemplatiivinen” välillä vallitsee 1200- ja 1300-lukujen taitteessa eläneen saksalaisen teologin Mestari Eckhartin mystiikanteologiassa. Lisäksi on tarkoitus selvittää mitä tuon suhteen kautta on mahdollista paljastaa Eckhartin mystiikanteologiasta laajemmin. Tutkimuksen metodi on systemaattinen analyysi ja päälähteinä käytetään Eckhartin saksankielisiä saarnoja. Erityisesti analysoidaan Eckhartin Martta-Maria -perikooppia (Lk.10:38–42) käsitteleviä saarnoja Pr.86 ja Pr.2. Lisäksi lähteinä käytetään muita Eckhartin saksankielisiä saarnoja ja muuta tuotantoa siinä määrin kuin niiden mukaan ottaminen auttaa paremmin ymmärtämään saarnojen intentioita. Jo ensimmäisistä kristillisistä vuosisadoista lähtien Luukkaan evankeliumin kertomus Martasta ja Mariasta on ollut aktiivisen ja kontemplatiivisen elämän locus classicus. Siksi tutkimuskysymykseen vastaamiseksi on valittu juuri Eckhartin sitä käsittelevät saarnat. Itse tutkimuskysymyksen valintaan on vaikuttanut puolestaan se, että Eckhart tulkitsee perikooppia häntä edeltävästä tulkintatraditiosta selvästi poikkeavalla tavalla ja nostaa Martan sisaruksista edistyneemmäksi. Tutkimus etenee seuraavalla tavalla. Luvussa 2 avataan käsitteiden ”aktiivinen” ja ”kontemplatiivinen” sisältöä sekä käsitellään kysymystä siitä miten niiden välistä suhdetta on kirkon historiassa tulkittu. Se tapahtuu esittelemällä kolme keskeistä tulkintalinjaa: normaalikirkollinen, monastinen ja mendikanttisääntökuntien tulkinta. Luvussa 3 käydään läpi Eckhartin elämää, tuotantoa ja harhaoppisuustuomiota sekä hänen teologiansa keskeisiä jäsentäviä periaatteita. Koska Eckhart on suomalaiselle yleisölle verrattain tuntematon teologi, aihetta käsitellään hieman laajemmin kuin pro gradu -tukielmassa on yleensä tapana. Luvussa 4 perehdytään Martta-Maria -perikooppiin ja sen pitkään tulkintahistoriaan. Luvussa 5 analysoidaan Eckhartin saarna Pr.86, luvussa 6 Pr.2. Luvussa 7 tutkimuksen tulokset kootaan yhteen. Eckhartin saarnoja analysoimalla paljastuu, että hän tulkitsee aktiivisen ja kontemplatiivisen elämän suhteen häntä edeltävästä traditiosta poikkeavalla tavalla. Eckhartia edeltävänä aikana kontemplatiivisia pyrkimyksiä ja Mariaa oli pidetty kristillisessä kirkossa aktiivista elämää ihailtavampana ja ansiollisempana jo tuhat vuotta. Siihen oli vaikuttanut erityisesti se, että 400-luvulta lähtien aina 1200-luvulle asti luostarit olivat Länsi-Euroopan sivistyksen ja teologian keskuksia. Sen vuoksi juuri monastisia ihanteita – erityisesti kontemplatiivisia pyrkimyksiä Jumalan välittömään katselemiseen – pidettiin pitkään kristillisen elämän ihanteina. Eckhart on kuitenkin osa uutta tulkintatraditiota jossa perinteisen klausuurin rajat pyrittiin laajentamaan luostarin muureista koskemaan koko maailmaa. Tämä uusi tulkintatraditio oli ominaista erityisesti mendikanttisääntökunnille (fransiskaanit ja dominikaanit) sekä begiiniyhteisöille, joissa kontemplatiivinen ja aktiivinen elämä pyrittiin yhdistämään yhdeksi kristilliseksi elämäksi. Tutkimuksessa käy ilmi, että suhteessa laajempiin tulkintatradition linjoihin, Eckhart voidaan liittää luontevasti osaksi näiden sääntökuntien uusia orastavia tulkintoja. Niiden mukaan kristillistä täydellisyyttä ei tavoiteta kääntymällä pois päin maailmasta vaan sitä kohti. Sen on kuitenkin tarkoitus tapahtua niin, että aktiivisuus maailmassa nousee kontemplatiivisesta elämänmuodosta käsin. Toisaalta tutkimuksessa paljastuu myös, että Eckhart menee vielä edellä mainittuja uusia tulkintojakin pidemmälle. Mendikanttisääntökunnissa kontemplatiivisuus säilytti yleensä vielä jonkinlaisen ensisijaisuuden aktiivisuuteen nähden, siihen valmistavana ja sen mahdollistavana vaiheena. Eckhart saarnaa kuitenkin niiden täydellisen ykseyden ja samanaikaisuuden puolesta. Hänelle täydellisyyttä edustaa Betanian sisaruksista Martta joka on ”neitsyt-vaimo”, koskematon ja puhdas, mutta joka kuitenkin samalla synnyttää. Neitsyyden ja vaimouden täydellisen samanaikaisuuden korostaminen nousee puolestaan Eckhartin voimakkaasta sitoutumisesta uusplatoniseen metafysiikkaan. Eckhartin ontologia on ”dynaamista ontologiaa”, jossa kaikki ymmärretään Jumalan yliajalliseksi emanaatioksi. Tulkitsemalla mm. Proklosta, Eckhart esittää, että kaikki luotu on olemassa ensisijaisesti ja täydellisenä ikuisuudessa syntyvässä Pojassa ja vain formaalisesti ja vajavaisella tavalla havaittavassa todellisuudessa. Kristillinen täydellisyys on Eckhartille paluuta tuohon varsinaiseen olemiseen ikuisuudessa syntyvässä Pojassa. Paluu tapahtuu irrottautumalla (abegescheiden) kuvista (bilde) eli hyväksymällä, että Jumala ei ole missään käsitteissä, eikä häntä tavoiteta samoin kuin olemassa olevat asiat tavoitetaan. Sikäli kun ihminen riisutaan riippuvuudestaan kuvista, sikäli hän murtautuu (durchbrechen) takaisin siihen perustaan (grunt) jossa Poika ikuisesti syntyy. Perustasta käsin ihmisen on puolestaan mahdollista synnyttää sellaista aktiivisuutta ja toimintaa, joka ei ole itsekkyyden ja egon tahraamaa suorittamista ja kaupankäyntiä. Tutkimuksessa käy ilmi myös se, kuinka keskeinen rooli ymmärryksen (intellectus) kategorialla on kuvista luopumisen prosessissa ja Jumalan kaltaisuuden realisoitumisessa ihmisessä. Juuri ymmärtämisaktin (intelligere) puolesta ihminen on Eckhartin mukaan eniten Jumalan kaltainen ja osa Jumalan ikuisuudessa tapahtuvaa emanaatiota.
Resumo:
Tutkielmassani selvitän, millä tavalla sosiaalisesti syrjäytyneen, kuten asunnottoman, on mahdollista osallistua yhteiskunnan toimintaan ja itseään koskevaan päätöksentekoon. Tutkimuskysymykseni ovat: Toteutuvatko perustuslain 14 § ja 19 §:ssä säädetyt oikeudet, ja ovatko viranomaisten toimet riittäviä edistämään syrjäytyneiden asunnottomien itsenäistä asumista sekä lisäämään vaikutusmahdollisuuksia itseään koskevassa päätöksenteossa. Voisiko deliberatiivisen demokratiamallin avulla vahvistaa syrjäytyneiden yhteiskunnallista osallistumista, ja siten helpottaa asunnottomuusongelmaa. Asunnottomia oli vuonna 2006 noin 7 400 henkilöä. Syitä joutua asunnottomaksi on useita. Valtaosalla ongelmat ovat kasautuneet, minkä jälkeen itsenäinen selviäminen on hankaloitunut. Asunnottomilla on usein monia eri ongelmia kuten pitkäaikaissairauksia, työttömyyttä ja päihteiden väärinkäyttöä. Avioero on yksi keskeisistä yksittäisistä syistä etenkin miehille päätyä asunnottomaksi. Maahanmuuttajien asunnottomuus voi olla seurausta pyrkimyksestä integroitua yhteiskuntaan: Muuttaessa sijoituspaikkakunnalta esimerkiksi ystävien, työn tai opiskelun vuoksi kasvukeskukseen, maahanmuuttajan voi olla vaikeaa saada asuntoa. Näin työn tai koulutuspaikan vastaanottaminen voi pakottaa maahanmuuttajan ottamaan riskin menettää asunto. Sosiaalisesti syrjäytyneeksi voidaan määritellä ihminen, joka ei kykene tai halua sopeutua normaalina pidettyyn elämään yhteiskunnassa. Tämä tutkimuksissa käytetty normaalin elämän määritelmä muotoutuu yhteiskunnan arvojen ja käytäntöjen pohjalta. Syrjäytyminen voi tarkoittaa myös sitä, että ihminen kokee itsensä ulkopuoliseksi yhteiskunnasta. Syrjäytymistä aiheuttavatkin siten toistuvat syrjinnän ja voimattomuuden kokemukset sekä hankaluus vaikuttaa itseään koskevaan päätöksentekoon. Asunnottomien yö –tapahtumassa syksyllä 2007 vapaaehtoiset haastattelivat asunnottomuutta kokeneita. Haastattelut on julkaistu internetissä ja ne ovat vapaasti tutkijoiden, toimittajien ja poliitikkojen käytettävissä. Useissa haastatteluissa asunnottomat kertovat, että he eivät koe olevansa täysivaltaisia yhteiskunnan jäseniä. Haastatteluissa kritisoidaan sitä, että poliitikot ja sosiaalityöntekijät päättävät asunnottomuuden hoidosta sekä asunnottomia koskevista asioista ilman, että asunnottomilla on mahdollisuutta vaikuttaa päätöksentekoon. Turhautumisen tunne paistoi läpi useissa haastatteluissa. Useissa vastauksissa asunnottomat vaativat poliitikkoja ja sosiaalityöntekijöitä perehtymään asunnottomien arjen elämään. Deliberatiivisessa demokratiassa yksi keskeisistä ajatuksista on, että vain sellaiset päätökset, jotka on tehty kaikille avoimen keskustelun ja vapaan tahdonmuodostuksen pohjalta voivat saada hyväksynnän ja luottamuksen kansalta sekä muodostua sitoviksi. Deliberatiivisessa demokratiakäsityksessä on kyse siitä, että asioista päätetään yhdessä, julkisen ja tasa-arvoisen keskustelun sekä harkinnan pohjalta. Keskeistä on myös, että kaikkien, joita päätökset koskettavat, täytyy voida osallistua päätöksiä edeltävään keskusteluun. Erityisesti Young ja Bohman korostavat, että myös sosiaalisesti syrjäytyneellä tulee olla mahdollisuus osallistua poliittiseen keskusteluun ja itseään koskevaan päätöksentekoon. Muun muassa koulutuksen kautta opitaan rauhallinen, asiallinen ja kielellisesti oikea argumentaatiotapa. Ihmisten erilaisuus ja kouluttamattomuus eivät Youngin mukaan saa estää mahdollisuutta osallistua yhteiskunnassa käytävään poliittiseen keskusteluun. Tutkimuskysymykseeni, lisäävätkö viranomaiset toiminnallaan yksilön mahdollisuutta vaikuttaa itseään koskevaan päätöksentekoon ja edistävätkö he yksilön mahdollisuuksia osallistua yhteiskunnalliseen toimintaan, vastaan eivät. Kuitenkin viranomaisten mahdollisuudet edistää perustuslaissa säädettyjä velvollisuuksia ovat poliittisten päättäjien budjetoinnin vuoksi rajoitettuja. Helsingin sosiaaliasiamiehet pitivät huolestuttavana sitä, että sosiaalityöntekijät pakotetaan toimimaan sekä lainsäädännön että ammattietiikkansa vastaisesti. Sosiaaliasiamiesten raportin perusteella voisi päätellä, että ainakin Helsingissä viranomaisilla olisi tahtoa toimia lain velvoittamalla tavalla. Asunnottomista suurin osa asuu Helsingissä ja Pääkaupunkiseudulla, joten tämän perusteella tutkimuskysymykseeni voi vastata yleistäen Helsingin esimerkin pohjalta. Syrjäytymistutkijoiden tulkinnan mukaan syrjäytyminen ja siitä pahimmillaan seuraava asunnottomuus johtuvat osittain ihmisten kokemien vaikutusmahdollisuuksien puutteesta. Deliberatiivisen demokratian tavoitteena on luoda sellainen demokraattinen malli, jossa poliittinen keskustelu ja vaikutusmahdollisuudet olisivat kaikkien yhteiskunnan jäsenten saavutettavissa. Syrjäytymistutkimuksen valossa deliberatiivinen demokratia voisi olla malli, jonka avulla vahvistettaisiin sosiaalisesti syrjäytyneiden kuten asunnottomien vaikutusmahdollisuuksia. Myös asunnottomien haastatteluissa nousi esille toive tulla kuulluksi. Moni kommentoi, että asunnottomuuden hoidosta ja heidän asioistaan päättävät sellaiset ihmiset, joilla ei ole todellista tietoa asunnottomien arjesta ja toiveista. Deliberatiivisen demokratian malli voisi näiden tutkimusten valossa olla keino lisätä osallistumismahdollisuuksia ja vähentää sitä kautta myös syrjäytymistä ja asunnottomuutta.
Resumo:
The structure of the abnormal product 1a formed in the Knoevenagel condensation of 2-carbethoxycyclohexanone and malononitrile has been further confirmed. Oxidation of the tetrahydroisoquinoline 3b using Na2Cr2O-AcOH-H2SO4 gave the keto isoquinoline 3d and the isoquinoline-1-carboxylic acid 5a. The acid chloride of 5a was condensed with diethyl ethoxymagnesiomalonate to afford after decarbethoxylation the methyl ketone 5d which on Baeyer-Villiger oxidation gave a mixture of the acetate 1g and the title compound 1b. The unambiguous synthesis of 1b confirms the structure assigned earlier to the title compound also formed during the partial hydrolysis of the diethoxy compound 1c. Condensation of 2-acetylcyclohexane-1,3-dione with malononitrile gave the quinoline derivative 4c which on ethylation yielded the ketoquinoline 4d. The present studies have confirmed that the quinoline compound 4a is also formed in the condensation of 2-acetylcyclohexanone and cyanoacetamide.
Resumo:
The reaction of the title complexes (FIG. 1) with N-bromosuccinimide or bromine in chloroform yields isomeric bromo complexes on substitution of the γ-CH carbon proton by bromine. The brominated products have been characterised by ir, pmr, electronic absorption spectra, conductivity and magnetic susceptibility measurements. The linkage isomerisation of the brominated products in chloroform has been shown to depend on the diamine residue.
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The study explores new ideational changes in the information strategy of the Finnish state between 1998 and 2007, after a juncture in Finnish governing in the early 1990s. The study scrutinizes the economic reframing of institutional openness in Finland that comes with significant and often unintended institutional consequences of transparency. Most notably, the constitutional principle of publicity (julkisuusperiaate), a Nordic institutional peculiarity allowing public access to state information, is now becoming an instrument of economic performance and accountability through results. Finland has a long institutional history in the publicity of government information, acknowledged by law since 1951. Nevertheless, access to government information became a policy concern in the mid-1990s, involving a historical narrative of openness as a Nordic tradition of Finnish governing Nordic openness (pohjoismainen avoimuus). International interest in transparency of governance has also marked an opening for institutional re-descriptions in Nordic context. The essential added value, or contradictory term, that transparency has on the Finnish conceptualisation of governing is the innovation that public acts of governing can be economically efficient. This is most apparent in the new attempts at providing standardised information on government and expressing it in numbers. In Finland, the publicity of government information has been a concept of democratic connotations, but new internationally diffusing ideas of performance and national economic competitiveness are discussed under the notion of transparency and its peer concepts openness and public (sector) information, which are also newcomers to Finnish vocabulary of governing. The above concepts often conflict with one another, paving the way to unintended consequences for the reforms conducted in their name. Moreover, the study argues that the policy concerns over openness and public sector information are linked to the new drive for transparency. Drawing on theories of new institutionalism, political economy, and conceptual history, the study argues for a reinvention of Nordic openness in two senses. First, in referring to institutional history, the policy discourse of Nordic openness discovers an administrative tradition in response to new dilemmas of public governance. Moreover, this normatively appealing discourse also legitimizes the new ideational changes. Second, a former mechanism of democratic accountability is being reframed with market and performance ideas, mostly originating from the sphere of transnational governance and governance indices. Mobilizing different research techniques and data (public documents of the Finnish government and international organizations, some 30 interviews of Finnish civil servants, and statistical time series), the study asks how the above ideational changes have been possible, pointing to the importance of nationalistically appealing historical narratives and normative concepts of governing. Concerning institutional developments, the study analyses the ideational changes in central steering mechanisms (political, normative and financial steering) and the introduction of budget transparency and performance management in two cases: census data (Population Register Centre) and foreign political information (Ministry for Foreign Affairs). The new policy domain of governance indices is also explored as a type of transparency. The study further asks what institutional transformations are to be observed in the above cases and in the accountability system. The study concludes that while the information rights of citizens have been reinforced and recalibrated during the period under scrutiny, there has also been a conversion of institutional practices towards economic performance. As the discourse of Nordic openness has been rather unquestioned, the new internationally circulating ideas of transparency and the knowledge economy have entered this discourse without public notice. Since the mid 1990s, state registry data has been perceived as an exploitable economic resource in Finland and in the EU public sector information. This is a parallel development to the new drive for budget transparency in organisations as vital to the state as the Population Register Centre, which has led to marketization of census data in Finland, an international exceptionality. In the Finnish Ministry for Foreign Affairs, the post-Cold War rhetorical shift from secrecy to performance-driven openness marked a conversion in institutional practices that now see information services with high regards. But this has not necessarily led to the increased publicity of foreign political information. In this context, openness is also defined as sharing information with select actors, as a trust based non-public activity, deemed necessary amid the global economic competition. Regarding accountability system, deliberation and performance now overlap, making it increasingly difficult to identify to whom and for what the public administration is accountable. These evolving institutional practices are characterised by unintended consequences and paradoxes. History is a paradoxical component in the above institutional change, as long-term institutional developments now justify short-term reforms.
Resumo:
The dissertation consists of an introductory chapter and three essays that apply search-matching theory to study the interaction of labor market frictions, technological change and macroeconomic fluctuations. The first essay studies the impact of capital-embodied growth on equilibrium unemployment by extending a vintage capital/search model to incorporate vintage human capital. In addition to the capital obsolescence (or creative destruction) effect that tends to raise unemployment, vintage human capital introduces a skill obsolescence effect of faster growth that has the opposite sign. Faster skill obsolescence reduces the value of unemployment, hence wages and leads to more job creation and less job destruction, unambiguously reducing unemployment. The second essay studies the effect of skill biased technological change on skill mismatch and the allocation of workers and firms in the labor market. By allowing workers to invest in education, we extend a matching model with two-sided heterogeneity to incorporate an endogenous distribution of high and low skill workers. We consider various possibilities for the cost of acquiring skills and show that while unemployment increases in most scenarios, the effect on the distribution of vacancy and worker types varies according to the structure of skill costs. When the model is extended to incorporate endogenous labor market participation, we show that the unemployment rate becomes less informative of the state of the labor market as the participation margin absorbs employment effects. The third essay studies the effects of labor taxes on equilibrium labor market outcomes and macroeconomic dynamics in a New Keynesian model with matching frictions. Three policy instruments are considered: a marginal tax and a tax subsidy to produce tax progression schemes, and a replacement ratio to account for variability in outside options. In equilibrium, the marginal tax rate and replacement ratio dampen economic activity whereas tax subsidies boost the economy. The marginal tax rate and replacement ratio amplify shock responses whereas employment subsidies weaken them. The tax instruments affect the degree to which the wage absorbs shocks. We show that increasing tax progression when taxation is initially progressive is harmful for steady state employment and output, and amplifies the sensitivity of macroeconomic variables to shocks. When taxation is initially proportional, increasing progression is beneficial for output and employment and dampens shock responses.
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All positive-strand RNA viruses utilize cellular membranes for the assembly of their replication complexes, which results in extensive membrane modification in infected host cells. These alterations act as structural and functional scaffolds for RNA replication, providing protection for the viral double-stranded RNA against host defences. It is known that different positive-strand RNA viruses alter different cellular membranes. However, the origin of the targeted membranes, the mechanisms that direct replication proteins to specific membranes and the steps in the formation of the membrane bound replication complex are not completely understood. Alphaviruses (including Semliki Forest virus, SFV), members of family Togaviridae, replicate their RNA in association with membranes derived from the endosomal and lysosomal compartment, inducing membrane invaginations called spherules. Spherule structures have been shown to be the specific sites for RNA synthesis. Four replication proteins, nsP1-nsP4, are translated as a polyprotein (P1234) which is processed autocatalytically and gives rise to a membrane-bound replication complex. Membrane binding is mediated via nsP1 which possesses an amphipathic α-helix (binding peptide) in the central region of the protein. The aim of this thesis was to characterize the association of the SFV replication complex with cellular membranes and the modification of the membranes during virus infection. Therefore, it was necessary to set up the system for determining which viral components are needed for inducing the spherules. In addition, the targeting of the replication complex, the formation site of the spherules and their intracellular trafficking were studied in detail. The results of current work demonstrate that mutations in the binding peptide region of nsP1 are lethal for virus replication and change the localization of the polyprotein precursor P123. The replication complex is first targeted to the plasma membrane where membrane invaginations, spherules, are induced. Using a specific regulated endocytosis event the spherules are internalized from the plasma membrane in neutral carrier vesicles and transported via an actin-and microtubule-dependent manner to the pericentriolar area. Homotypic fusions and fusions with pre-existing acidic organelles lead to the maturation of previously described cytopathic vacuoles with hundreds of spherules on their limiting membranes. This work provides new insights into the membrane binding mechanism of SFV replication complex and its role in the virus life cycle. Development of plasmid-driven system for studying the formation of the replication complex described in this thesis allows various applications to address different steps in SFV life cycle and virus-host interactions in the future. This trans-replication system could be applied for many different viruses. In addition, the current work brings up new aspects of membranes and cellular components involved in SFV replication leading to further understanding in the formation and dynamics of the membrane-associated replication complex.
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The first glycyl radical in an enzyme was described 20 years ago and since then the family of glycyl radical enzymes (GREs) has expanded to include enzymes catalysing five chemically distinct reactions. The type enzymes of the family, anaerobic ribonucleotide reductase (RNRIII) and pyruvate formate lyase (PFL) had been studied long before it was known that they are GREs. Spectroscopic measurements on the radical and an observation that exposure to oxygen irreversibly inactivates the enzymes by cleavage of the protein proved that the radical is located on a particular glycine residue, close to the C-terminus of the protein. Both anaerobic RNRIII and PFL, are important for many anaerobic and facultative anaerobic bacteria as RNRIII is responsible for the synthesis of DNA precursors and PFL catalyses a key metabolic reaction in glycolysis. The crystal structures of both were solved in 1999 and they revealed that, although the enzymes do not share significant sequence identity, they share a similar structure - the radical site and residues necessary for catalysis are buried inside a ten stranded $\ualpha $/$\ubeta $-barrel. GREs are synthesised in an inactive form and are post-translationally activated by an activating enzyme which uses S-adenosyl methionine and an iron-sulphur cluster to generate the radical. One of the goals of this thesis work was to crystallise the activating enzyme of PFL. This task is challenging as, like GREs, the activating component is inactivated by oxygen. The experiments were therefore carried out in an oxygen free atmosphere. This is the first report of a crystalline GRE activating enzyme. Recently several new GREs have been characterised, all sharing sequence similarity to PFL but not to RNRIII. Also, the genome sequencing projects have identified many PFL-like GREs of unknown function, usually annotated as PFLs. In the present thesis I describe the grouping of these PFL family enzymes based on the sequence similarity and analyse the conservation patterns when compared to the structure of E. coli PFL. Based on this information an activation route is proposed. I also report a crystal structure of one of the PFL-like enzymes with unknown function, PFL2 from Archaeoglobus fulgidus. As A. fulgidus is a hyperthermophilic organism, possible mechanisms stabilising the structure are discussed. The organisation of an active site of PFL2 suggests that the enzyme may be a dehydratase. Keywords: glycyl radical, enzyme, pyruvate formate lyase, x-ray crystallography, bioinformatics
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Meckel syndrome (MKS, MIM 249000) is a severe developmental disorder that leads to death already in utero or shortly after birth. MKS diagnosis can be established by a careful ultrasound examination already at 11-14 weeks of gestation. The main features of MKS are occipital meningoencephalocele, cystic kidney dysplasia and fibrotic changes of the liver. In addition, polydactyly is frequently reported in the cases. The aim of the study was to characterize the molecular and functional defects in MKS. In this study we were able to identify two major MKS mutations in Finnish population, which cover over 90% of the cases. The first mutation is a 29 bp intronic deletion in the MKS1 gene (c.1483-7_35del) that is found in 70% of the families and the second is a C>T substitution in the coding region of CC2D2A (c.1762C>T), that is found in 20% of the MKS families. Both of these mutations result in abnormal splicing. The discovery of the disease genes has revealed that MKS is caused by primary cilia dysfunction. MKS1 gene has a conserved B9 domain, and it is found in the predicted ciliary proteome. CC2D2A protein is also found in the predicted ciliary proteome and it has a Ca2+ binding domain. The number of genes behind MKS has increased rapidly in the past years and to date, mutations have been identified in five genes (MKS1, TMEM67/MKS3, CEP290/MKS4, RPGRIP1L/MKS5 and CC2D2A/MKS6). Identification of the disease genes mutations has also revealed that MKS is an allelic disorder with other syndromes with overlapping phenotypes. Disorders that are caused by primary cilia dysfunction are collectively known as ciliopathies. Sequence analysis of all the known MKS genes in Finnish and non-Finnish families available to us, where the mutation was still unknown, revealed mutations in 14 out of the 30 families included in the study. When we collected all the reported mutations in MKS genes in different syndromes we could see that there was clearly a genotype-syndrome correlation between the mutations and the syndromes, since the same pair of mutations has never been reported in different syndromes. The basic molecular events behind MKS will not only give us information of this syndrome, but also significant novel information on early fetal development in general.
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This study deals with algal species occurring commonly in the Baltic Sea: haptophyte Prymnesium parvum, dinoflagellates Dinophysis acuminata, D. norvegica and D. rotundata, and cyanobacterium Nodularia spumigena. The hypotheses are connected to the toxicity of the species, to the factors determining toxicity, to the consequences of toxicity and to the transfer of toxins in the aquatic food web. Since the Baltic Sea is severely eutrophicated, the fast-growing haptophytes have potential in causing toxic blooms. In our studies, the toxicity (as haemolytic activity) of the haptophyte P. parvum was highest under phosphorus-limited conditions, but the cells were toxic also under nitrogen limitation and under nutrient-balanced growth conditions. The cellular nutrient ratios were tightly related to the toxicity. The stoichiometric flexibility for cellular phosphorus quota was higher than for nitrogen, and nitrogen limitation led to decreased biomass. Negative allelopathic effects on another algae (Rhodomonas salina) could be observed already at low P. parvum cell densities, whereas immediate lysis of R. salina cells occurred at P. parvum cell densities corresponding to natural blooms. Release of dissolved organic carbon from the R. salina cells was measured within 30 minutes, and an increase in bacterial number and biomass was measured within 23 h. Because of the allelopathic effect, formation of a P. parvum bloom may accelerate after a critical cell density is reached and the competing species are eliminated. A P. parvum bloom indirectly stimulates bacterial growth, and alters the functioning of the planktonic food web by increasing the carbon transfer through the microbial loop. Our results were the first reports on DSP toxins in Dinophysis cells in the Gulf of Finland and on PTX-2 in the Baltic Sea. Cellular toxin contents in Dinophysis spp. ranged from 0.2 to 149 pg DTX-1 cell-1 and from 1.6 to 19.9 pg PTX-2 cell-1 in the Gulf of Finland. D. norvegica was found mainly around the thermocline (max. 200 cells L-1), whereas D. acuminata was found in the whole mixed layer (max. 7 280 cells L-1). Toxins in the sediment trap corresponded to 1 % of DTX-1 and 0.01 % PTX-2 of the DSP pool in the suspended matter. This indicates that the majority of the DSP toxins does not enter the benthic community, but is either decomposed in the water column, or transferred to higher trophic levels in the planktonic food chain. We found that nodularin, produced by Nodularia spumigena, was transferred to the copepod Eurytemora affinis through three pathways: by grazing on filaments of small Nodularia, directly from the dissolved pool, and through the microbial food web by copepods grazing on ciliates, dinoflagellates and heterotrophic nanoflagellates. The estimated proportion of the microbial food web in nodularin transfer was 22-45 % and 71-76 % in our two experiments, respectively. This highlights the potential role of the microbial food web in the transfer of toxins in the planktonic food web.
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Staphylococcus aureus is one of the most important bacteria that cause disease in humans, and methicillin-resistant S. aureus (MRSA) has become the most commonly identified antibiotic-resistant pathogen in many parts of the world. MRSA rates have been stable for many years in the Nordic countries and the Netherlands with a low MRSA prevalence in Europe, but in the recent decades, MRSA rates have increased in those low-prevalence countries as well. MRSA has been established as a major hospital pathogen, but has also been found increasingly in long-term facilities (LTF) and in communities of persons with no connections to the health-care setting. In Finland, the annual number of MRSA isolates reported to the National Infectious Disease Register (NIDR) has constantly increased, especially outside the Helsinki metropolitan area. Molecular typing has revealed numerous outbreak strains of MRSA, some of which have previously been associated with community acquisition. In this work, data on MRSA cases notified to the NIDR and on MRSA strain types identified with pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and staphylococcal cassette chromosome mec (SCCmec) typing at the National Reference Laboratory (NRL) in Finland from 1997 to 2004 were analyzed. An increasing trend in MRSA incidence in Finland from 1997 to 2004 was shown. In addition, non-multi-drug resistant (NMDR) MRSA isolates, especially those resistant only to methicillin/oxacillin, showed an emerging trend. The predominant MRSA strains changed over time and place, but two internationally spread epidemic strains of MRSA, FIN-16 and FIN-21, were related to the increase detected most recently. Those strains were also one cause of the strikingly increasing invasive MRSA findings. The rise of MRSA strains with SCCmec types IV or V, possible community-acquired MRSA was also detected. With questionnaires, the diagnostic methods used for MRSA identification in Finnish microbiology laboratories and the number of MRSA screening specimens studied were reviewed. Surveys, which focused on the MRSA situation in long-term facilities in 2001 and on the background information of MRSA-positive persons in 2001-2003, were also carried out. The rates of MRSA and screening practices varied widely across geographic regions. Part of the NMDR MRSA strains could remain undetected in some laboratories because of insufficient diagnostic techniques used. The increasing proportion of elderly population carrying MRSA suggests that MRSA is an emerging problem in Finnish long-term facilities. Among the patients, 50% of the specimens were taken on a clinical basis, 43% on a screening basis after exposure to MRSA, 3% on a screening basis because of hospital contact abroad, and 4% for other reasons. In response to an outbreak of MRSA possessing a new genotype that occurred in a health care ward and in an associated nursing home of a small municipality in Northern Finland in autumn 2003, a point-prevalence survey was performed six months later. In the same study, the molecular epidemiology of MRSA and methicillin-sensitive S. aureus (MSSA) strains were also assessed, the results to the national strain collection compared, and the difficulties of MRSA screening with low-level oxacillin-resistant isolates encountered. The original MRSA outbreak in LTF, which consisted of isolates possessing a nationally new PFGE profile (FIN-22) and internationally rare MLST type (ST-27), was confined. Another previously unrecognized MRSA strain was found with additional screening, possibly indicating that current routine MRSA screening methods may be insufficiently sensitive for strains possessing low-level oxacillin resistance. Most of the MSSA strains found were genotypically related to the epidemic MRSA strains, but only a few of them had received the SCCmec element, and all those strains possessed the new SCCmec type V. In the second largest nursing home in Finland, the colonization of S. aureus and MRSA, and the role of screening sites along with broth enrichment culture on the sensitivity to detect S. aureus were studied. Combining the use of enrichment broth and perineal swabbing, in addition to nostrils and skin lesions swabbing, may be an alternative for throat swabs in the nursing home setting, especially when residents are uncooperative. Finally, in order to evaluate adequate phenotypic and genotypic methods needed for reliable laboratory diagnostics of MRSA, oxacillin disk diffusion and MIC tests to the cefoxitin disk diffusion method at both +35°C and +30°C, both with or without an addition of sodium chloride (NaCl) to the Müller Hinton test medium, and in-house PCR to two commercial molecular methods (the GenoType® MRSA test and the EVIGENETM MRSA Detection test) with different bacterial species in addition to S. aureus were compared. The cefoxitin disk diffusion method was superior to that of oxacillin disk diffusion and to the MIC tests in predicting mecA-mediated resistance in S. aureus when incubating at +35°C with or without the addition of NaCl to the test medium. Both the Geno Type® MRSA and EVIGENETM MRSA Detection tests are usable, accurate, cost-effective, and sufficiently fast methods for rapid MRSA confirmation from a pure culture.
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GDP-L-fucose: synthesis and role in inflammation The migration of leukocytes from intravascular locations to extravascular sites is essential to the immune responses. The initial attachment of leukocytes to the endothelium and the rolling step of the leukocyte extravasation cascade are mediated by selectins, a family of cell adhesion molecules on cell surfaces. Selectins are able to recognize glycoproteins and glycolipids containing the tetrasaccharide sialyl Lewis x (sLex, Neu5Acα2-3Galβ1-4(Fucα1-3)GlcNAc). Several glycosyltransferases are involved in the biosynthesis of sLex, fucosyltransferase VII (Fuc-TVII) being the last enzyme to modify the sLex structure. Fuc-TVII transfers L-fucose from GDP-L-fucose to sialylated N-acetyllactosamine. GDP-L-fucose is synthesized in the cytosol via two different metabolic pathways. The major, constitutively active de novo pathway involves conversion of GDP-α-D-mannose to GDP-β-L-fucose. In the alternative salvage pathway, L-fucokinase synthesizes from free fucose L-fucose-1-phosphate, which is further converted to GDP-L-fucose by GDP-L-fucose pyrophosphorylase. GDP-L-fucose is translocated from the cytosol to Golgi for fucosylation via the GDP-fucose transporter. This thesis involved the study of the synthesis of GDP-L-fucose via the salvage pathway: cloning and expression of murine L-fucokinase and GDP-L-fucose pyrophosphorylase. The gene expression levels of these enzymes were found to be relatively high in various tissues; the mRNA levels were highest in brain, ovary and testis. This study also describes molecular cloning of rat fucosyltransferase VII (FUT7) and its expression as a functional enzyme. Gene expression levels of GDP-L-fucose synthesizing enzymes, GDP-fucose transporter and FUT7 were determined in inflamed tissues as well as cancer cells. Our results revealed a clear upregulation of the enzymes involved in the synthesis of GDP-L-fucose via de novo pathway, GDP-fucose transporter and FUT7 in inflamed tissues and in cancer cells. On the contrary, the GDP-L-fucose salvage pathway was found to be irrelevant in inflammation and in tumorigenesis. Furthermore, our results indicated the transcriptional coregulation of Golgi transporters involved in the synthesis of sulfo sLex, i.e. CMP-sialic acid, GDP-fucose and 3 phosphoadenosine 5 -phosphosulfate transporters, in inflammation.
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The seasonal occurrence of sea ice that annually covers almost half the Baltic Sea area provides a unique habitat for halo- and cold temperature-tolerant extremophiles. Baltic Sea ice biology has more than 100 years of tradition that began with the floristic observation of species by the early pioneers using light microscopic techniques that were the only thing available at the time. Since the discovery of life within sea ice, more technologies have become available for taxonomy. Electron microscopy and genetic evidence have been used to identify sea ice biota revealing increased numbers of taxa. Meanwhile ecologists have used light microscopic cell enumeration in addition to the chemical and physical properties of sea ice in attempts to explain the food web structure of sea ice and its functions. Thus, during the Baltic winter, the sea ice hosts more abundant and diverse microbial communities than the water column beneath it. These communities are typically dominated by autotrophic diatoms together with a diverse assortment of dinoflagellates, auto- and heterotrophic flagellates, ciliates, metazoan rotifers and bacteria, which are mostly responsible for the recycling of nutrients. This thesis comprises ecological and systematic studies. In addition to the results of the previous studies carried out on landfast ice, the data presented here provide new insight into the spatial distribution of pelagial sea ice, which has remained largely unexplored. The studies reveal spatial heterogeneity in the pelagial sea ice of the Gulf of Bothnia. There were mismatches in chlorophyll-a concentrations and in photosynthetic efficiencies of the communities studied. The temporal succession was followed and experimental studies performed investigating the community responses towards increased or decreased light in landfast ice in the Gulf of Finland. The systematic studies carried out with established dinoflagellate cultures revealed a new resting cyst belonging to common sea ice dinoflagellate, Scrippsiella hangoei (Schiller) Larsen 1995. The cyst can be used to explain the overwintering of this species during prolonged periods of darkness. The dissimilarities and similarities in the material isolated from the sea ice called for description of a new subspecies Heterocapsa arctica ssp. frigida. The cells obtained in the cultured material were unlike those of the previously described species, necessitating description of ssp. frigida. As a result of its own unique habitus, the subspecies had been noted by Finnish taxonomists during the past three decades and thus its annual occurrence and geographical distribution in the Baltic Sea. This illustrates how combining ecology and systematics increases our understanding of organisms.
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Cells of every living organism on our planet − bacterium, plant or animal − are organized in such a way that despite differences in structure and function they utilize the same metabolic energy represented by electrochemical proton gradient across a membrane. This gradient of protons is generated by the series of membrane bound multisubunit proteins, Complex I, II, III and IV, organized in so-called respiratory or electron transport chain. In the eukaryotic cell it locates in the inner mitochondrial membrane while in the bacterial cell it locates in the cytoplasmic membrane. The function of the respiratory chain is to accept electrons from NADH and ubiquinol and transfer them to oxygen resulting in the formation of water. The free energy released upon these redox reactions is converted by respiratory enzymes into an electrochemical proton gradient, which is used for synthesis of ATP as well as for many other energy dependent processes. This thesis is focused on studies of the first member of the respiratory chain − NADH:ubiquinone oxidoreductase or Complex I. This enzyme has a boot-shape structure with hydrophilic and hydrophobic domains, the former of which has all redox groups of the protein, the flavin and eight to nine iron-sulfur clusters. Complex I serves as a proton pump coupling transfer of two electrons from NADH to ubiquinone to the translocation of four protons across the membrane. So far the mechanism of energy transduction by Complex I is unknown. In the present study we applied a set of different methods to study the electron and proton transfer reactions in Complex I from Escherichia coli. The main achievement was the experiment that showed that the electron transfer through the hydrophilic domain of Complex I is unlikely to be coupled to proton transfer directly or to conformational changes in the protein. In this work for the first time properties of all redox centers of Complex I were characterized in the intact purified bacterial enzyme. We also probed the role of several conserved amino acid residues in the electron transfer of Complex I. Finally, we found that highly conserved amino acid residues in several membrane subunits form a common pattern with a very prominent feature – the presence of a few lysines within the membrane. Based on the experimental data, we suggested a tentative principle which may govern the redox-coupled proton pumping in Complex I.