88 resultados para 10040109 TM-13
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Mika KT Pajusen väitös "Towards 'a real reunion'?" – Archbishop Aleksi Lehtonen's efforts for closer relations with the Church of England 1945–1951 on yleiseen kirkkohistoriaan lukeutuva tutkimus Englannin kirkon ja Suomen evankelis-luterilaisen kirkon välisistä suhteista Aleksi Lehtosen arkkipiispakaudella 1945–1951. Suhteita on tutkittu kolmesta näkökulmasta: ekumeenisesta, poliittisesta ja kirkkopoliittisesta. Tutkimuskausi alkaa pastori H.M. Waddamsin joulukuussa 1944 Suomeen tekemän vierailun jälkimainingeista ja päättyy arkkipiispa Lehtosen kuolemaan pääsiäisenä 1951. Kirkollisten suhteiden kehitystä rytmittivät lukuisat vierailut, jotka osoittivat Englannin kirkon asenteen muuttumisen sodan aikaisesta neuvostomyönteisyydestä kylmän sodan aikaiseen täysin vastakkaiseen kantaan. Englantilaiset vieraat kohtasivat Suomessa sekä kirkon että yhteiskunnan ylimmän johdon. Molemmat maat olivat valmiita tukemaan hyviä kirkollisia suhteita tilanteen niin salliessa, joskaan eivät kovin suunnitelmallisesti. Suomen evankelis-luterilainen kirkko käytti hyviä suhteita Englannin kirkkoon saadakseen tukea ja ymmärrystä omalle kirkolleen ja yhteiskunnalleen kokemaansa Neuvostoliiton uhkaa vastaan erityisesti vaaran vuosina 1944–1948. Englannin kirkko halusi tukea suomalaista sisarkirkkoaan, mutta varoi, ettei tuottaisi tuellaan enemmän haittaa kuin hyötyä suhteessa Neuvostoliittoon. Sodan jälkeinen ekumeeninen jälleenrakentaminen lähensi kirkkoja toisiinsa. Lehtonen pyrki jatkamaan 1930-luvun kirkkojen välisiä, ehtoollisvieraanvaraisuuden saavuttaneita neuvotteluita kohti täyttä kirkollista yhteyttä. Häntä motivoi sekä evankelis-katolinen teologia että pyrkimys tukea oman maan ja kirkon läntisiä yhteyksiä. Tämä haastoi Englannin kirkon ekumeenisen linjan, joka Suomen kirkon sijasta pyrki jatkamaan neuvotteluja Tanskan, Norjan ja Islannin luterilaisten kirkkojen kanssa, joilla ei vielä ollut virallista ekumeenista sopimusta Englannin kirkon kanssa. Lehtosen pyrkimyksistä huolimatta Englannin kirkko päätyi jättämään Suomen tilanteen hautumaan. Sillä se tarkoitti suhteiden koetinkivenä olleen historiallisen piispuuden leviämistä läpi Suomen kirkon ennen kuin katsoi olevansa valmis jatkamaan kohti täyttä kirkollista yhteyttä. Molemmissa kirkoissa vaikutti pieni, innokkaiden, lähempiä suhteita toivoneiden kirkollisten vaikuttajien ydinjoukko. Englantilaisia Suomen-ystäviä motivoi tarve auttaa Suomea hankalassa poliittisessa tilanteessa. Suomessa arkkipiispa Lehtonen tuki korkeakirkollista liturgista liikettä, jolla oli läheinen yhteys anglikaanisuuteen, mutta joka sai vastaansa vanhoilliset pietistit. Suomen kirkon yleinen mielipide asettui etupäässä pietistiselle kannalle, jolle anglikaanisuus näyttäytyi teologisesti sekä liian katolisena että liian reformoituna. Kirkolliset suhteet tasaantuivat vuoden 1948 Lambeth-konferenssin jälkeen, joka rohkaisi anglikaanisia kirkkoja hyväksymään 1930-luvun neuvottelujen lähempiin kirkollisiin suhteisiin tähtäävät suositukset. Lehtonen näytti tyytyvän tähän. Samaan aikaan lähempää kirkollista kanssakäymistä tukenut ekumeeninen jälleenrakennus tuli tiensä päähän. Lehtonen jatkoi läheisempien suhteiden edistämistä, mutta hänen intonsa hiipui yhdessä heikkenevän terveydentilan kanssa. Osoituksena Lehtosen linjan kapeudesta Suomen evankelis-luterilaisen kirkon piispoista ei löytynyt hänen kuoltuaan ketään, joka olisi jatkanut hänen aktiivista anglikaanimyönteistä linjaansa.
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Tutkielma käsittelee Markuksen evankeliumissa esiintyvää Jumala Poika -arvonimen merkitystä. Evankelista Markus käyttää useissa yhteyksissä Jeesuksesta Jumalan Poika -tunnustusformelia. Mitä hän sillä tarkoittaa? Oliko Markus ensimmäinen kirjoittaja, joka käytti tätä arvonimeä? Kuinka evankeliumissa esiintyvät kohdat selittyvät lukijalle? Miten Jeesuksesta tuli Jumalan Poika, ja mitä tuolloin kyseisellä termillä ylipäätään tarkoitettiin? Näihin kysymyksiin etsitään tässä tutkimuksessa vastauksia. Johdannossa käsitellään Jumalan poika -arvonimen syntykontekstia, Markuksen evankeliumin syntyä sekä messiassalaisuuden teemaa. Wreden työn pohjalta syntynyttä messiassalaisuuden ongelmaa käsitellään melko laajasti, koska redaktiokritiikin kannalta sen tulokset ovat hyvin merkittäviä. Analyysiosiossa tarkastellaan yksityiskohtaisesti kymmentä Markuksen mainintaa Jeesuksesta Jumalan Poikana. Näissä maininnoissaan evankelista käyttää apuna eri osapuolia, jotka vakuuttavasti antavat tunnustuksensa Jumalan Pojasta. Evankelista antaa itse oman henkilökohtaisen tunnustuksensa heti evankeliumin alussa kohdassa Mk. 1:1. Tunnustusten ketju jatkuu Jumalan tunnustuksilla kohdissa Mk. 1:1-9 ja 9:2-7. Saastaiset henget tunnustavat myös Jeesuksen Jumalan Pojaksi kohdissa Mk. 3:11 ja 5:1-13. Metafyysisen maailman lisäksi myös näkyvän maailman luonnonvoimat tunnustavat Jeesuksen jumalallisen käskyvallan kohdassa Mk. 6:45-52, jossa Jeesus murtaa fysiikan lait kävelemällä veden päällä. Traditioon kuulunut paralleelikohta on Jeesuksen myrskyn tyynnyttäminen kohdassa Mk. 4:35-41. Tähän tutkimukseen on valittu ainoastaan ensimmäinen. Jeesuksen opetuslapsijoukosta Pietari tunnustaa Jeesuksen Jumalan Pojaksi kohdassa Mk. 8:27-30. Jeesus itse tunnustaa ylimmäisen papin edessä oman olemuksensa kohdassa Mk. 14:50-62 ja kertomalla vertauksen viinitarhan vuokraajista kohdassa Mk. 12:1-12. Evankeliumin tunnustusten sarjan päättää roomalainen upseeri Jeesuksen ristin äärellä kohdassa Mk. 15:39. Tunnustusten näkökulmasta tämä merkitsee täydellistä loppua Markuksen kirjalliselle työlle. Johtopäätöksissä pohditaan mm. sitä, miten historiallisesta Jeesus Nasaretilaisesta tuli Jumalan Poika? Miksi kastekertomus on tässä niin keskeinen? Yhtenä taustatekijänä lienee Lähi-idän alueella vuosisatoja vaikuttaneet Mesopotamian aikaiset uskonnolliset traditiot. Jumalan Pojan terminologista sisältöä päätellään kahden kysymyksen avulla. Millä perusteella Markus esittää Jeesuksen Jumalan Pojaksi, ja toiseksi missä merkityksessä Jeesus on Jumalan Poika? Vastauksena on, että Jeesus on Jumalan Poika, koska Jumala asetti hänet kasteen yhteydessä messiaaniseen tehtäväänsä. Toiseksi Jeesus on Jumala Poika siinä merkityksessä, että hän toteutti Jumalan antamaa tehtävää oikeana kärsivänä Jumalan Poikana, joka apostoli Paavalin käyttämän tradition mukaan asetettiin kuoleman jälkeen asemaan, jossa hänellä on valta (Rm. 1:4). Johtopäätöksenä on, että tradition tasolla Jeesus oli saarnaaja, ihmeiden tekijä ja parantaja, jolla oli erityisen läheinen suhde Jumalaan. Markuksen redaktion tasolla Jeesus oli metafyysinen Jumalan Poika. Evankeliumisssa punoutuvat yhteen Jeesuksesta kertova traditio ja Markuksen redaktio.
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Tämän pro gradu -työn tarkoituksena on selvittää tekstin Jer 20:7-13 jumalakuvaa ja muita ”tekstin puhujan” ilmaisemia vuorovaikutussuhteita ja vaihtelevia tunteita. On kuitenkin epäselvää, missä määrin Jeremian kirja tai sen yksittäiset jaksot kuvaavat profeetan persoonaa ja historiallista taustaa. Tekstit voivat kuvata myös muita myöhempiä tilanteita ja asenteita. Tämän tutkimuksen pääasiallinen eksegeettinen metodi on syvyyspsykologinen. Se saattaa pystyä kertomaan jotakin siitä, miten tutkittava teksti peilaa menneisyyden kokemuksellisia kaavoja. Samaan tapaan kuten psykohistoriassa, tutkimus ei yritä tutkia, tulkita tai rekonstruoida tradition tai historian Jeremiaa. Syvyyspsykologinen eksegeesi on tunnistettu jo aiemmin, mutta suomalaisessa tutkimuksessa sitä ei vielä ole sovellettu yksittäisiin teksteihin. Tämän tutkimuksen tutkimusasetelma avaa tekstin sisäisiä ja vaihtelevia vuorovaikutussuhteita eli objektisuhteita. Tutkimus nimittää tätä vuorovaikutussuhteiden analyysiä objektisuhdeanalyysiksi. Se perustuu teologian tohtori, psykoanalyytikko Matti Hyrckin psykoanalyyttiseen suhteessaolon perusmielikuvien teoriaan (SPT), jonka hän esittelee väitöskirjassaan Mielen kuvat Jumalasta (1995). Tekstin Jahve-kuvat on nähtävä objektirepresentaatioina. Nämä vahvasti värittyneet representaatiot ja kuvat kertovat enemmän kokijasta itsestään kuin niistä objekteista, joiden kuviksi ne ovat syntyneet. Käsitys objektien sisäsyntyisyydestä mahdollistaa Hyrckillä objektisuhteiden systematisoinnin ja SPT:n luomisen. Siten emotionaaliset silmälasit on tämän tutkimuksen tekijän mielestä mahdollista valjastaa myös tutkijan käyttöön. Tutkimuksen laaja näkökulmia hakeva teoriaosuus varmistaa tämän. Hermeneuttinen ”kolmen maailman malli” on lukijakeskeisyyteen ja kulttuurihyppyyn arvokas työväline. Jeremian kirja sisältää useita osin runomuotoisia valituksia, joista tutkittava teksti on viimeinen. Valituslaulujen sarja päättyy tutkittavaa tekstiä seuraavaan syntymäpäivän kiroamiseen jakeissa 14-18. Valituksen edellä kontekstina on joitakin kertomuksia Jeremiasta, mutta vasta jakeessa 20:2 Jeremia nimetään profeetaksi. Muuten valittaja on nimetön. Jeremia-kertomusten kehys on tässä toimituksellinen ja valituksen jälkeen seuraa deuteronomistista saarnaa Juudaa ja Jerusalemia vastaan. Tutkimus selvittää jakeiden 7-13 rakennetta, sisältöä ja tulkintaa ensin lähinnä laji- ja kirjallisuus- kriittisesti. Tutkimus osoittaa, että Jeremian valitus noudattaa yksilön valituslaulun kaavaa, mutta ei kuitenkaan yksiselitteisesti taivu lajin usein stereotyyppisiin tarkoituksiin. Suurin syy tähän on tekstin proosa- ja runomuodon vaihtelu ja sisällön hajanaisuus. Edes valituksen ydintä ei voi varmistaa, vaikka valituslaulun nuorimpina osina on tyypillisesti helppo pitää loppupuolen kollektiivisia lisiä. Varsinainen valitus on jakeissa 7-9 ja jakeet 10-13 ovat todennäköisimmin monivaiheinen päätössarja. Tutkimuksen keskeiset objektisuhdeteoreettiset peruskäsitteet sisäinen subjekti ja sisäinen objekti ovat ihmisen tiedostamattoman tason mielikuvia. Varhaisen tilan vuorovaikutusmielikuvien sisäisinä subjekteina ovat Riippuvainen ja Itseriittoinen. Ne ovat vaihtelevissa suhteissa Houkuttajan ja Hallitsijan muotoisia sisäisiä objekteja kohtaan. Myöhäisessä tilassa objekteille on syytä antaa uudet nimet: Vetäytyjä, Vaatija ja Parantaja. Tutkimus etenee osoittamalla tekstin ja SPT:n mukaisen mallin samankaltaisuuksia. Samalla on ollut mahdollista ottaa kantaa myös tekstin saumoihin ja tekstin syntyprosessiin. Tekstin objekti osoittautuu pääosin Hallitsijaksi, sillä Houkuttajan muotoisista jumaluuksista on kollektiivisesti pyritty tekemään pesäeroa Jerusalemin temppelin hävityksestä lähtien. Silti muistoista ja Houkuttajaksikin värittyneistä kaipuun ja pelon muodoista ei päästä eroon. Valituksen alkujakeita 7-9 leimaa Riippuvaisen masennus ja Itseriittoisen häpeä. Jakeissa 11-13 Hallitsijan muotoinen Jahve Sebaot tarjoaa hierarkkista symbioosia. Myöhäistä Vaatijaa ei tutkittavassa tekstissä ole kuin vanhurskaan käsitteenä, joka deuteronomistisessa teologiassa perustuu Jahven sanan kuulemiseen ja lain noudattamiseen. Tutkimus pyrkii osoittamaan, että kaikilla kokemuksilla on jollakin tavalla sekä yhteisöä että yksilöä eheyttäviä tarkoituksia. Kun valitus päättyy sarjaan vakuutuksia ja huipentuu kollektiiviseen ylistyskehotukseen, myös niillä on tarkoitus. Yksi osa tutkimustehtävää on ollut testata psykoanalyyttisen objektisuhdeteoreettisen metodin toimivuutta eksegeettisessä tutkimuksessa. Vaikka tulokset ovat suuntaa antavia, metodi on osoittautunut toimivaksi.
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The highly dynamic remodeling of the actin cytoskeleton is responsible for most motile and morphogenetic processes in all eukaryotic cells. In order to generate appropriate spatial and temporal movements, the actin dynamics must be under tight control of an array of actin binding proteins (ABPs). Many proteins have been shown to play a specific role in actin filament growth or disassembly of older filaments. Very little is known about the proteins affecting recycling i.e. the step where newly depolymerized actin monomers are funneled into new rounds of filament assembly. A central protein family involved in the regulation of actin turnover is cyclase-associated proteins (CAP, called Srv2 in budding yeast). This 50-60 kDa protein was first identified from yeast as a suppressor of an activated RAS-allele and a factor associated with adenylyl cyclase. The CAP proteins harbor N-terminal coiled-coil (cc) domain, originally identified as a site for adenylyl cyclase binding. In the N-terminal half is also a 14-3-3 like domain, which is followed by central proline-rich domains and the WH2 domain. In the C-terminal end locates the highly conserved ADP-G-actin binding domain. In this study, we identified two previously suggested but poorly characterized interaction partners for Srv2/CAP: profilin and ADF/cofilin. Profilins are small proteins (12-16 kDa) that bind ATP-actin monomers and promote the nucleotide exchange of actin. The profilin-ATP-actin complex can be directly targeted to the growth of the filament barbed ends capped by Ena/VASP or formins. ADF/cofilins are also small (13-19 kDa) and highly conserved actin binding proteins. They depolymerize ADP-actin monomers from filament pointed ends and remain bound to ADP-actin strongly inhibiting nucleotide exchange. We revealed that the ADP-actin-cofilin complex is able to directly interact with the 14-3-3 like domain at the N-terminal region of Srv2/CAP. The C-terminal high affinity ADP-actin binding site of Srv2/CAP competes with cofilin for an actin monomer. Cofilin can thus be released from Srv2/CAP for the subsequent round of depolymerization. We also revealed that profilin interacts with the first proline-rich region of Srv2/CAP and that the binding occurs simultaneously with ADP-actin binding to C-terminal domain of Srv2/CAP. Both profilin and Srv2/CAP can promote nucleotide exchange of actin monomer. Because profilin has much higher affinity to ATP-actin than Srv2/CAP, the ATP-actin-profilin complex is released for filament polymerization. While a disruption of cofilin binding in yeast Srv2/CAP produces a severe phenotype comparable to Srv2/CAP deletion, an impairment of profilin binding from Srv2/CAP results in much milder phenotype. This suggests that the interaction with cofilin is essential for the function of Srv2/CAP, whereas profilin can also promote its function without direct interaction with Srv2/CAP. We also show that two CAP isoforms with specific expression patterns are present in mice. CAP1 is the major isoform in most tissues, while CAP2 is predominantly expressed in muscles. Deletion of CAP1 from non-muscle cells results in severe actin phenotype accompanied with mislocalization of cofilin to cytoplasmic aggregates. Together these studies suggest that Srv2/CAP recycles actin monomers from cofilin to profilin and thus it plays a central role in actin dynamics in both yeast and mammalian cells.
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The complexity of life is based on an effective energy transduction machinery, which has evolved during the last 3.5 billion years. In aerobic life, the utilization of the high oxidizing potential of molecular oxygen powers this machinery. Oxygen is safely reduced by a membrane bound enzyme, cytochrome c oxidase (CcO), to produce an electrochemical proton gradient over the mitochondrial or bacterial membrane. This gradient is used for energy-requiring reactions such as synthesis of ATP by F0F1-ATPase and active transport. In this thesis, the molecular mechanism by which CcO couples the oxygen reduction chemistry to proton-pumping has been studied by theoretical computer simulations. By building both classical and quantum mechanical model systems based on the X-ray structure of CcO from Bos taurus, the dynamics and energetics of the system were studied in different intermediate states of the enzyme. As a result of this work, a mechanism was suggested by which CcO can prevent protons from leaking backwards in proton-pumping. The use and activation of two proton conducting channels were also enlightened together with a mechanism by which CcO sorts the chemical protons from pumped protons. The latter problem is referred to as the gating mechanism of CcO, and has remained a challenge in the bioenergetics field for more than three decades. Furthermore, a new method for deriving charge parameters for classical simulations of complex metalloenzymes was developed.
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Wound healing is a complex process that requires an interplay between several cell types. Classically, fibroblasts have been viewed as producers of extracellular matrix, but more recently they have been recognized as orchestrators of the healing response, promoting and directing, inflammation and neovascularization processes. Compared to those from healthy tissue, inflammation-associated fibroblasts display a dramatically altered phenotype and have been described as sentinel cells, able to switch to an immunoregulatory profile on cue. However, the activation mechanism still remains largely uncharacterized. Nemosis is a model for stromal fibroblast activation. When normal human primary fibroblasts are deprived of growth support they cluster, forming multicellular spheroids. Clustering results in upregulation of proinflammatory markers such as cyclooxygenase-2 and secretion of prostaglandins, proteinases, cytokines, and growth factors. Fibroblasts in nemosis induce wound healing and tumorigenic responses in many cell types found in inflammatory and tumor microenvironments. This study investigated the effect of nemotic fibroblasts on two components of the vascular system, leukocytes and endothelium, and characterized the inflammation-promoting responses that arose in these cell types. Fibroblasts in nemosis were found to secrete an array of chemotactic cytokines and attract leukocytes, as well as promote their adhesion to the endothelium. Nuclear factor-kB, the master regulator of many inflammatory responses, is activated in nemotic fibroblasts. Nemotic fibroblasts are known to produce large amounts of hepatocyte growth factor, a motogenic and angiogenic factor. Also, as shown in this study, they produce vascular endothelial growth factor. These two factors induced migratory and sprouting responses in endothelial cells, both required for neovascularization. Nemotic fibroblasts also caused a decrease in the expression of adherens and tight junction components on the surface of endothelial cells. The results allow the conclusion that fibroblasts in nemosis share many similarities with inflammation-associated fibroblasts. Both inflammation and stromal fibroblasts are known to be involved in tumorigenesis and tumor progression. Nemosis may be viewed as a model for stromal fibroblast activation, or it may correlate with cell-cell interactions between adjacent fibroblasts in vivo. Nevertheless, due to nemosis-derived production of proinflammatory cytokines and growth factors, fibroblast nemosis may have therapeutic potential as an inducer of controlled tissue repair. Knowledge of stromal fibroblast activation gained through studies of nemosis, could provide new strategies to control unwanted inflammation and tumor progression.
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Proteolysis is important in bacterial pathogenesis and colonization of animal and plant hosts. In this work I have investigated the functions of the bacterial outer membrane proteases, omptins, of Yersinia pestis and Salmonella enterica. Y. pestis is a zoonotic pathogen that causes plague and has evolved from gastroenteritis-causing Yersinia pseudotuberculosis about 13 000 years ago. S. enterica causes gastroenteritis and typhoid fever in humans. Omptins are transmembrane β-barrels with ten antiparallel β-strands and five surface-exposed loops. The loops are important in substrate recognition, and variation in the loop sequences leads to different substrate selectivities between omptins, which makes omptins an ideal platform to investigate functional adaptation and to alter their polypeptide substrate preferences. The omptins Pla of Y. pestis and PgtE of S. enterica are 75% identical in their amino acid sequences. Pla is a multifunctional protein with proteolytic and non-proteolytic functions, and it increases bacterial penetration and proliferation in the host. Functions of PgtE increase migration of S. enterica in vivo and bacterial survival in mouse macrophages, thus enhancing bacterial spread within the host. Mammalian plasminogen/fibrinolytic system maintains the balance between coagulation and fibrinolysis and participates in several cellular processes, e.g., cell migration and degradation of extracellular matrix proteins. This system consists of activation cascades, which are strictly controlled by several regulators, such as plasminogen activator inhibitor 1 (PAI-1), α2-antiplasmin (α2AP), and thrombin-activatable fibrinolysis inhibitor (TAFI). This work reveals novel interactions of the omptins of Y. pestis and S. enterica with the regulators of the plasminogen/fibrinolytic system: Pla and PgtE inactivate PAI-1 by cleavage at the reactive site peptide bond, and degrade TAFI, preventing its activation to TAFIa. Structure-function relationship studies with Pla showed that threonine 259 of Pla is crucial in plasminogen activation, as it prevents degradation of the plasmin catalytic domain by the omptin and thus maintains plasmin stability. In this work I constructed chimeric proteins between Pla and Epo of Erwinia pyrifoliae that share 78% sequence identity to find out which amino acids and regions in Pla are important for its functions. Epo is neither a plasminogen activator nor an invasin, but it degrades α2AP and PAI-1. Cumulative substitutions towards Pla sequence turned Epo into a Pla-like protein. In addition to threonine 259, loops 3 and 5 are critical in plasminogen activation by Pla. Turning Epo into an invasin required substitution of 31 residues located at the extracellular side of the Epo protein above the lipid bilayer, and also of the β1-strand in the N-terminal transmembrane region of the protein. These studies give an example of how omptins adapt to novel functions that advantage their host bacteria in different ecological niches.
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Extraintestinal pathogenic Escherichia coli (ExPEC) represent a diverse group of strains of E. coli, which infect extraintestinal sites, such as the urinary tract, the bloodstream, the meninges, the peritoneal cavity, and the lungs. Urinary tract infections (UTIs) caused by uropathogenic E. coli (UPEC), the major subgroup of ExPEC, are among the most prevalent microbial diseases world wide and a substantial burden for public health care systems. UTIs are responsible for serious morbidity and mortality in the elderly, in young children, and in immune-compromised and hospitalized patients. ExPEC strains are different, both from genetic and clinical perspectives, from commensal E. coli strains belonging to the normal intestinal flora and from intestinal pathogenic E. coli strains causing diarrhea. ExPEC strains are characterized by a broad range of alternate virulence factors, such as adhesins, toxins, and iron accumulation systems. Unlike diarrheagenic E. coli, whose distinctive virulence determinants evoke characteristic diarrheagenic symptoms and signs, ExPEC strains are exceedingly heterogeneous and are known to possess no specific virulence factors or a set of factors, which are obligatory for the infection of a certain extraintestinal site (e. g. the urinary tract). The ExPEC genomes are highly diverse mosaic structures in permanent flux. These strains have obtained a significant amount of DNA (predictably up to 25% of the genomes) through acquisition of foreign DNA from diverse related or non-related donor species by lateral transfer of mobile genetic elements, including pathogenicity islands (PAIs), plasmids, phages, transposons, and insertion elements. The ability of ExPEC strains to cause disease is mainly derived from this horizontally acquired gene pool; the extragenous DNA facilitates rapid adaptation of the pathogen to changing conditions and hence the extent of the spectrum of sites that can be infected. However, neither the amount of unique DNA in different ExPEC strains (or UPEC strains) nor the mechanisms lying behind the observed genomic mobility are known. Due to this extreme heterogeneity of the UPEC and ExPEC populations in general, the routine surveillance of ExPEC is exceedingly difficult. In this project, we presented a novel virulence gene algorithm (VGA) for the estimation of the extraintestinal virulence potential (VP, pathogenicity risk) of clinically relevant ExPECs and fecal E. coli isolates. The VGA was based on a DNA microarray specific for the ExPEC phenotype (ExPEC pathoarray). This array contained 77 DNA probes homologous with known (e.g. adhesion factors, iron accumulation systems, and toxins) and putative (e.g. genes predictably involved in adhesion, iron uptake, or in metabolic functions) ExPEC virulence determinants. In total, 25 of DNA probes homologous with known virulence factors and 36 of DNA probes representing putative extraintestinal virulence determinants were found at significantly higher frequency in virulent ExPEC isolates than in commensal E. coli strains. We showed that the ExPEC pathoarray and the VGA could be readily used for the differentiation of highly virulent ExPECs both from less virulent ExPEC clones and from commensal E. coli strains as well. Implementing the VGA in a group of unknown ExPECs (n=53) and fecal E. coli isolates (n=37), 83% of strains were correctly identified as extraintestinal virulent or commensal E. coli. Conversely, 15% of clinical ExPECs and 19% of fecal E. coli strains failed to raster into their respective pathogenic and non-pathogenic groups. Clinical data and virulence gene profiles of these strains warranted the estimated VPs; UPEC strains with atypically low risk-ratios were largely isolated from patients with certain medical history, including diabetes mellitus or catheterization, or from elderly patients. In addition, fecal E. coli strains with VPs characteristic for ExPEC were shown to represent the diagnostically important fraction of resident strains of the gut flora with a high potential of causing extraintestinal infections. Interestingly, a large fraction of DNA probes associated with the ExPEC phenotype corresponded to novel DNA sequences without any known function in UTIs and thus represented new genetic markers for the extraintestinal virulence. These DNA probes included unknown DNA sequences originating from the genomic subtractions of four clinical ExPEC isolates as well as from five novel cosmid sequences identified in the UPEC strains HE300 and JS299. The characterized cosmid sequences (pJS332, pJS448, pJS666, pJS700, and pJS706) revealed complex modular DNA structures with known and unknown DNA fragments arranged in a puzzle-like manner and integrated into the common E. coli genomic backbone. Furthermore, cosmid pJS332 of the UPEC strain HE300, which carried a chromosomal virulence gene cluster (iroBCDEN) encoding the salmochelin siderophore system, was shown to be part of a transmissible plasmid of Salmonella enterica. Taken together, the results of this project pointed towards the assumptions that first, (i) homologous recombination, even within coding genes, contributes to the observed mosaicism of ExPEC genomes and secondly, (ii) besides en block transfer of large DNA regions (e.g. chromosomal PAIs) also rearrangements of small DNA modules provide a means of genomic plasticity. The data presented in this project supplemented previous whole genome sequencing projects of E. coli and indicated that each E. coli genome displays a unique assemblage of individual mosaic structures, which enable these strains to successfully colonize and infect different anatomical sites.
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With transplant rejection rendered a minor concern and survival rates after liver transplantation (LT) steadily improving, long-term complications are attracting more attention. Current immunosuppressive therapies, together with other factors, are accompanied by considerable long-term toxicity, which clinically manifests as renal dysfunction, high risk for cardiovascular disease, and cancer. This thesis investigates the incidence, causes, and risk factors for such renal dysfunction, cardiovascular risk, and cancer after LT. Long-term effects of LT are further addressed by surveying the quality of life and employment status of LT recipients. The consecutive patients included had undergone LT at Helsinki University Hospital from 1982 onwards. Data regarding renal function – creatinine and estimated glomerular filtration rate (GFR) – were recorded before and repeatedly after LT in 396 patients. The presence of hypertension, dyslipidemia, diabetes, impaired fasting glucose, and overweight/obesity before and 5 years after LT was determined among 77 patients transplanted for acute liver failure. The entire cohort of LT patients (540 patients), including both children and adults, was linked with the Finnish Cancer Registry, and numbers of cancers observed were compared to site-specific expected numbers based on national cancer incidence rates stratified by age, gender, and calendar time. Health-related quality of life (HRQoL), measured by the 15D instrument, and employment status were surveyed among all adult patients alive in 2007 (401 patients). The response rate was 89%. Posttransplant cardiovascular risk factor prevalence and HRQoL were compared with that in the age- and gender-matched Finnish general population. The cumulative risk for chronic kidney disease increased from 10% at 5 years to 16% at 10 years following LT. GFR up to 10 years after LT could be predicted by the GFR at 1 year. In patients transplanted for chronic liver disease, a moderate correlation of pretransplant GFR with later GFR was also evident, whereas in acute liver failure patients after LT, even severe pretransplant renal dysfunction often recovered. By 5 years after LT, 71% of acute liver failure patients were receiving antihypertensive medications, 61% were exhibiting dyslipidemia, 10% were diabetic, 32% were overweight, and 13% obese. Compared with the general population, only hypertension displayed a significantly elevated prevalence among patients – 2.7-fold – whereas patients exhibited 30% less dyslipidemia and 71% less impaired fasting glucose. The cumulative incidence of cancer was 5% at 5 years and 13% at 10. Compared with the general population, patients were subject to a 2.6-fold cancer risk, with non-melanoma skin cancer (standardized incidence ratio, SIR, 38.5) and non-Hodgkin lymphoma (SIR 13.9) being the predominant malignancies. Non-Hodgkin lymphoma was associated with male gender, young age, and the immediate posttransplant period, whereas old age and antibody induction therapy raised skin-cancer risk. HRQoL deviated clinically unimportantly from the values in the general population, but significant deficits among patients were evident in some physical domains. HRQoL did not seem to decrease with longer follow-up. Although 87% of patients reported improved working capacity, data on return to working life showed marked age-dependency: Among patients aged less than 40 at LT, 70 to 80% returned to work, among those aged 40 to 50, 55%, and among those above 50, 15% to 28%. The most common cause for unemployment was early retirement before LT. Those patients employed exhibited better HRQoL than those unemployed. In conclusion, although renal impairment, hypertension, and cancer are evidently common after LT and increase with time, patients’ quality of life remains comparable with that of the general population.
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Migraine is a common disease in children and adolescents, affecting roughly 10% of school-aged children. Recent studies have revealed an increasing incidence of childhood migraine, but migraine remains an underrecognized and undertreated condition in the pediatric population. Migraine attacks are painful and disabling and can affect a child´s life in many ways. Effective drug treatment is usually needed. The new migraine drugs, triptans, were introduced at the beginning of the 1990s and have since been shown to be very effective in the treatment of migraine attacks in adults. Although they are widely used in adults, the acute treatment of migraine in children and adolescents is still based on paracetamol and nonsteroidal anti-inflammatory drugs. Some children can control their attacks satisfactorily with simple analgesics, but at least one-third need more powerful treatments. When this thesis work commenced, hardly any information existed on the efficacy and safety of triptans in children. The study aim of the thesis was to identify more efficient treatments of migraine for children and adolescents by investigating the efficacy of sumatriptan nasal spray and oral rizatriptan compared with placebo in them. Sleep has an impact on migraine in many aspects. Despite the clinical relevance and common manifestation of sleep in the context of migraine in children, very little research data on the true frequency of sleep exist. As sleeping is so often related to childhood migraine, it can be a confounding factor in clinical drug trials of migraine treatments in children and adolescents. How the results of a sleeping child should be analyzed is under continual debate. The aim of the thesis was also to clarify this as well as to evaluate the frequency of sleeping during migraine attacks in children and factors affecting frequency. Both nasal sumatriptan and oral rizatriptan were effective (superior to placebo), and well tolerated in treatment of migraine attacks in children and adolescents aged 8-17 and 6-17 years, respectively. No serous adverse effects were observed. The results of this work suggest that nasal sumatriptan 20 mg and rizatriptan 10 mg can be effectively and safely used to treat migraine attacks in adolescents aged over 12 years if more effective drugs than NSAIDs are needed. No difference was observed in efficacy or safety of nasal sumatriptan and rizatriptan between children aged younger than 12 years and older children, but because the treated number of patients under 12 years is still small, more studies are needed before sumatriptan or rizatriptan can be recommended for use in this population. Sleeping during migraine attacks was very common, and most children at least occasionally slept during an attack. Falling asleep was especially common in children under eight years of age and during the first hour after the onset of attack. Children who were able to sleep soon after attack onset were more likely pain-free at two hours. Sleeping probably both improves recovery from a migraine attack and is a sign of headache relief. Falling asleep should be classified as a sign of headache relief in clinical drug trials when studying migraine treatments in children and adolescents.
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Background: The fecal neutrophil-derived proteins calprotectin and lactoferrin have proven useful surrogate markers of intestinal inflammation. The aim of this study was to compare fecal calprotectin and lactoferrin concentrations to clinically, endoscopically, and histologically assessed Crohn’s disease (CD) activity, and to explore the suitability of these proteins as surrogate markers of mucosal healing during anti-TNFα therapy. Furthermore, we studied changes in the number and expression of effector and regulatory T cells in bowel biopsy specimens during anti-TNFα therapy. Patients and methods: Adult CD patients referred for ileocolonoscopy (n=106 for 77 patients) for various reasons were recruited (Study I). Clinical disease activity was assessed with the Crohn’s disease activity index (CDAI) and endoscopic activity with both the Crohn’s disease index of severity (CDEIS) and the simple endoscopic score for Crohn’s disease (SES-CD). Stool samples for measurements of calprotectin and lactoferrin, and blood samples for CRP were collected. For Study II, biopsy specimens were obtained from the ileum and the colon for histologic activity scoring. In prospective Study III, after baseline ileocolonoscopy, 15 patients received induction with anti-TNFα blocking agents and endoscopic, histologic, and fecal-marker responses to therapy were evaluated at 12 weeks. For detecting changes in the number and expression of effector and regulatory T cells, biopsy specimens were taken from the most severely diseased lesions in the ileum and the colon (Study IV). Results: Endoscopic scores correlated significantly with fecal calprotectin and lactoferrin (p<0.001). Both fecal markers were significantly lower in patients with endoscopically inactive than with active disease (p<0.001). In detecting endoscopically active disease, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for calprotectin ≥200 μg/g were 70%, 92%, 94%, and 61%; for lactoferrin ≥10 μg/g they were 66%, 92%, 94%, and 59%. Accordingly, the sensitivity, specificity, PPV, and NPV for CRP >5 mg/l were 48%, 91%, 91%, and 48%. Fecal markers were significantly higher in active colonic (both p<0.001) or ileocolonic (calprotectin p=0.028, lactoferrin p=0.004) than in ileal disease. In ileocolonic or colonic disease, colon histology score correlated significantly with fecal calprotectin (r=0.563) and lactoferrin (r=0.543). In patients receiving anti-TNFα therapy, median fecal calprotectin decreased from 1173 μg/g (range 88-15326) to 130 μg/g (13-1419) and lactoferrin from 105.0 μg/g (4.2-1258.9) to 2.7 μg/g (0.0-228.5), both p=0.001. The relation of ileal IL-17+ cells to CD4+ cells decreased significantly during anti-TNF treatment (p=0.047). The relation of IL-17+ cells to Foxp3+ cells was higher in the patients’ baseline specimens than in their post-treatment specimens (p=0.038). Conclusions: For evaluation of CD activity, based on endoscopic findings, more sensitive surrogate markers than CDAI and CRP were fecal calprotectin and lactoferrin. Fecal calprotectin and lactoferrin were significantly higher in endoscopically active disease than in endoscopic remission. In both ileocolonic and colonic disease, fecal markers correlated closely with histologic disease activity. In CD, these neutrophil-derived proteins thus seem to be useful surrogate markers of endoscopic activity. During anti-TNFα therapy, fecal calprotectin and lactoferrin decreased significantly. The anti-TNFα treatment was also reflected in a decreased IL-17/Foxp3 cell ratio, which may indicate improved balance between effector and regulatory T cells with treatment.
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Transforming growth factor β signalling through Smad3 in allergy Allergic diseases, such as atopic dermatitis, asthma, and contact dermatitis are complex diseases influenced by both genetic and environmental factors. It is still unclear why allergy and subsequent allergic disease occur in some individuals but not in others. Transforming growth factor (TGF)-β is an important immunomodulatory and fibrogenic factor that regulates cellular processes in injured and inflamed skin. TGF-β has a significant role in the regulation of the allergen-induced immune response participating in the development of allergic and asthmatic inflammation. TGF-β is known to be an immunomodulatory factor in the progression of delayed type hypersensitivity reactions and allergic contact dermatitis. TGF-β is crucial in regulating the cellular responses involved in allergy, such as differentiation, proliferation and migration. TGF-β signals are delivered from the cytoplasm to the nucleus by TGF-β signal transducers called Smads. Smad3 is a major signal transducer in TGF-β -signalling that controls the expression of target genes in the nucleus in a cell-type specific manner. The role of TGF-β-Smad3 -signalling in the immunoregulation and pathophysiology of allergic disorders is still poorly understood. In this thesis, the role of TGF-β-Smad -signalling pathway using Smad3 -deficient knock out mice in the murine models of allergic diseases; atopic dermatitis, asthma and allergic contact reactions, was examined. Smad3-pathway regulates allergen induced skin inflammation and systemic IgE antibody production in a murine model atopic dermatitis. The defect in Smad3 -signalling decreased Th2 cytokine (IL-13 and IL-5) mRNA expression in the lung, modulated allergen induced specific IgG1 response, and affected mucus production in the lung in a murine model of asthma. TGF-β / Smad3 -signalling contributed to inflammatory hypersensitivity reactions and disease progression via modulation of chemokine and cytokine expression and inflammatory cell recruitment, cell proliferation and regulation of the specific antibody response in a murine model of contact hypersensitivity. TGF-β modulates inflammatory responses - at least partly through the Smad3 pathway - but also through other compensatory, non-Smad-dependent pathways. Understanding the effects of the TGF-β signalling pathway in the immune system and in disease models can help in elucidating the multilevel effects of TGF-β. Unravelling the mechanisms of Smad3 may open new possibilities for treating and preventing allergic responses, which may lead to severe illness and loss of work ability. In the future the Smad3 signalling pathway might be a potential target in the therapy of allergic diseases.
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Within the last 15 years, several new leukoencephalopathies have been recognized. However, more than half of children with cerebral white matter abnormalities still have no specific diagnosis. Our aim was to classify unknown leukoencephalopathies and to identify new diseases among them. During the study, three subgroups of patients were delineated and examined further. First, we evaluated 38 patients with unknown leukoencephalopathy. Brain MRI findings were grouped into seven categories according to the predominant location of the abnormalities. The largest subgroups were myelination abnormalities (n=20) and periventricular white matter abnormalities (n=12). Six patients had uniform MRI findings with signal abnormalities in hemispheric white matter and in selective brain stem and spinal cord tracts. Magnetic resonance spectroscopy (MRS) showed elevated lactate and decreased N-acetylaspartate in the abnormal white matter. The patients presented with ataxia, tremor, distal spasticity, and signs of dorsal column dysfunction. This phenotype - leukoencephalopathy with brain stem and spinal cord involvement and elevated white matter lactate (LBSL) - was first published elsewhere in 2003. A new finding was development of a mild axonal neuropathy. The etiopathogenesis of this disease is unknown, but elevated white matter lactate in MRS suggests a mitochondrial disorder. Secondly, we studied 22 patients with 18q deletions. Clinical and MRI findings were correlated with molecularly defined size of the deletion. All patients with deletions between markers D18S469 and D18S1141 (n=18) had abnormal myelination in brain MRI, while four patients with interstitial deletions sparing that region, had normal myelination pattern. Haploinsufficiency of myelin basic protein is suggested to be responsible for this dysmyelination. Congenital aural atresia/stenosis was found in 50% of the cases and was associated with deletions between markers D18S812 (at 18q22.3) and D18S1141 (at q23). Last part of the study comprised 13 patients with leukoencephalopathy and extensive cerebral calcifications. They showed a spectrum of findings, including progressive cerebral cysts, retinal telangiectasias and angiomas, intrauterine growth retardation, skeletal and hematologic abnormalities, and severe intestinal bleeding, which overlap with features of the previously reported patients with "Coats plus" syndrome and "leukoencephalopathy with calcifications and cysts", suggesting that these disorders are related. All autopsied patients had similar neuropathologic findings showing calcifying obliterative microangiopathy. Our patients may represent an autosomally recessively inherited disorder because there were affected siblings and patients of both sexes. We have started genealogic and molecular genetic studies of this disorder.
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Visual acuities at the time of referral and on the day before surgery were compared in 124 patients operated on for cataract in Vaasa Central Hospital, Finland. Preoperative visual acuity and the occurrence of ocular and general disease were compared in samples of consecutive cataract extractions performed in 1982, 1985, 1990, 1995 and 2000 in two hospitals in the Vaasa region in Finland. The repeatability and standard deviation of random measurement error in visual acuity and refractive error determination in a clinical environment in cataractous, pseudophakic and healthy eyes were estimated by re-examining visual acuity and refractive error of patients referred to cataract surgery or consultation by ophthalmic professionals. Altogether 99 eyes of 99 persons (41 cataractous, 36 pseudophakic and 22 healthy eyes) with a visual acuity range of Snellen 0.3 to 1.3 (0.52 to -0.11 logMAR) were examined. During an average waiting time of 13 months, visual acuity in the study eye decreased from 0.68 logMAR to 0.96 logMAR (from 0.2 to 0.1 in Snellen decimal values). The average decrease in vision was 0.27 logMAR per year. In the fastest quartile, visual acuity change per year was 0.75 logMAR, and in the second fastest 0.29 logMAR, the third and fourth quartiles were virtually unaffected. From 1982 to 2000, the incidence of cataract surgery increased from 1.0 to 7.2 operations per 1000 inhabitants per year in the Vaasa region. The average preoperative visual acuity in the operated eye increased by 0.85 logMAR (in decimal values from 0.03to 0.2) and in the better eye 0.27 logMAR (in decimal values from 0.23 to 0.43) over this period. The proportion of patients profoundly visually handicapped (VA in the better eye <0.1) before the operation fell from 15% to 4%, and that of patients less profoundly visually handicapped (VA in the better eye 0.1 to <0.3) from 47% to 15%. The repeatability visual acuity measurement estimated as a coefficient of repeatability for all 99 eyes was ±0.18 logMAR, and the standard deviation of measurement error was 0.06 logMAR. Eyes with the lowest visual acuity (0.3-0.45) had the largest variability, the coefficient of repeatability values being ±0.24 logMAR and eyes with a visual acuity of 0.7 or better had the smallest, ±0.12 logMAR. The repeatability of refractive error measurement was studied in the same patient material as the repeatability of visual acuity. Differences between measurements 1 and 2 were calculated as three-dimensional vector values and spherical equivalents and expressed by coefficients of repeatability. Coefficients of repeatability for all eyes for vertical, torsional and horisontal vectors were ±0.74D, ±0.34D and ±0.93D, respectively, and for spherical equivalent for all eyes ±0.74D. Eyes with lower visual acuity (0.3-0.45) had larger variability in vector and spherical equivalent values (±1.14), but the difference between visual acuity groups was not statistically significant. The difference in the mean defocus equivalent between measurements 1 and 2 was, however, significantly greater in the lower visual acuity group. If a change of ±0.5D (measured in defocus equivalents) is accepted as a basis for change of spectacles for eyes with good vision, the basis for eyes in the visual acuity range of 0.3 - 0.65 would be ±1D. Differences in repeated visual acuity measurements are partly explained by errors in refractive error measurements.
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Cervical cancer is the second most common cancer among women globally. Most, probably all cases, arise through a precursor, cervical intraepithelial neoplasia (CIN). Effective cytological screening programmes and surgical treatments of precancerous lesions have dramatically reduced its prevalence and related mortality. Although these treatments are effective, they may have adverse effects on future fertility and pregnancy outcomes. The aim of this study was to evaluate the effects of surgical treatment of the uterine cervix on pregnancy and fertility outcomes, with the focus particularly on preterm birth. The general preterm birth rates and risk factors during 1987–2005 were studied. Long-term mortality rates of the treated women were studied. In this study, information from The Medical Birth Register (MBR), The Hospital Discharge Register (HDR), The Cause-of-Death Register (CDR), and hospital records were used. Treatments were performed during 1987–2003 and subsequent deliveries, IVF treatments and deaths were analyzed. The general preterm birth rate in Finland was relatively stable, varying from 5.1% to 5.4% during the study period (1987 to 2005), although the proportion of extremely preterm births had decreased substantially by 12%.The main risk factor as regards preterm birth was multiplicity, followed by elective delivery (induction of delivery or elective cesarean section), primiparity, in vitro fertilization treatment, maternal smoking and advanced maternal age. The risk of preterm birth and low birth weight was increased after any cervical surgical treatment; after conization the risk of preterm birth was almost two-fold (RR 1.99, 95% CI 1.81– 2.20). In the conization group the risk was the highest for very preterm birth (28–31 gestational weeks) and it was also high for extremely preterm birth (less than 28 weeks). In this group the perinatal mortality was also increased. In subgroup analysis, laser ablation was not associated with preterm birth. When comparing deliveries before and after Loop conization, we found that the risk of preterm birth was increased 1.94-fold (95% CI 1.10–3.40). Adjusting for age, parity, or both did not affect our results. Large or repeat cones increased the risk of preterm birth when compared with smaller cones, suggesting that the size of the removed cone plays a role. This was corroborated by the finding that repeat treatment increased the risk as much as five-fold when compared with the background preterm birth rate. We found that the proportion of IVF deliveries (1.6% vs. 1.5%) was not increased after treatment for CIN when adjusted for year of delivery, maternal age, or parity. Those women who received both treatment for CIN and IVF treatment were older and more often primiparous, which explained the increased risk of preterm birth. We also found that mortality rates were 17% higher among women previously treated for CIN. This excess mortality was particularly seen as regards increased general disease mortality and alcohol poisoning (by 13%), suicide (by 67%) and injury death (by 31%). The risk of cervical cancer was high, as expected (SMR 7.69, 95% CI 4.23–11.15). Women treated for CIN and having a subsequent delivery had decreased general mortality rate (by -22%), and decreased disease mortality (by -37%). However, those with preterm birth had increased general mortality (SMR 2.51, 95% CI 1.24–3.78), as a result of cardiovascular diseases, alcohol-related causes, and injuries. In conclusion, the general preterm birth rate has not increased in Finland, as in many other developed countries. The rate of extremely preterm births has even decreased. While other risk factors of preterm birth, such as multiplicity and smoking during pregnancy have decreased, surgical treatments of the uterine cervix have become more important risk factors as regards preterm birth. Cervical conization is a predisposing factor as regards preterm birth, low birth weight and even perinatal mortality. The most frequently used treatment modality, Loop conization, is also associated with the increased risk of preterm birth. Treatments should be tailored individually; low-grade lesions should not be treated at all among young women. The first treatment should be curative, because repeat treatments are especially harmful. The proportion of IVF deliveries was not increased after treatment for CIN, suggesting that current treatment modalities do not strongly impair fertility. The long-term risk of cervical cancer remains high even after many years post-treatment; therefore careful surveillance is necessary. In addition, accidental deaths and deaths from injury were common among treated women, suggesting risk-taking behavior of these women. Preterm birth seems be associated with extremely high mortality rates, due to cardiovascular, alcohol-related and injury deaths. These women could benefit from health counseling, for example encouragement in quitting smoking.