The purpose of the study was to: • Study the effect of vascular gas bubbles on the brain and lung • Study changes in the endothelial function caused by gas bubbles • Study the preventive effects of monoclonal anti-C5a antibody on functional changes caused by gas bubbles It is important to reveal any changes in the function of the endothelium caused by gas bubbles, as the endothelium probably plays an important role in the development of decompression sickness (DCS). Furthermore, we followed up previous studies using monoclonal anti-C5a antibody trying to prevent damages caused by gas bubbles. In order to prevent damages causes by gas bubbles and maybe prevent DCS, the mechanisms behind have to be revealed. This thesis is part of an ongoing project that for several years has tried to bring to light the “secrets” of DCS.

No description available.

The main purpose of the present work was to evaluate the efforts taken by the Norwegian surgical community in order to promote and enhance the standards of rectal cancer treatment on a national level, in particular: - to examine the outcome of rectal cancer surgery following implementation of total mesorectal excision as the standard rectal resection technique - to explore the prognostic impact of the circumferential resection margin on local recurrence, distant metastases and overall survival following mesorectal excision - to evaluate the oncological outcomes following mesorectal excision of cancer of the lower rectum, particularly the rates of local recurrence and overall survival for patients with tumours in this areas - to illustrate the influence of a rectal cancer registry as a quality control instrument on outcome of rectal treatment, and furthermore, to investigate the rates of postoperative mortality, anastomic leakage, local recurrence (LR) and overall survival related to hospital caseload among Norwegian hospitals during implementation of mesorectal excision.

The aim of this thesis is to explore why parents bring their children to homeopaths and to investigate the effect of homeopathic treatment for prevention of upper respiratory tract infections (URTI) in children. The reason for doing studies on this is that there has been a nearly threefold increase in the proportion of children among patients visiting Norwegian homeopaths. This raised the question of why it is so. Furthermore, recurrent respiratory complaints are a main reason why child patients consult homeopaths. This raised the question of the effect of homeopathic treatment in this patient group, because there is very little research on this. The thesis builds on four different studies conducted between August 2002 and June 2004. Parents of nine children that recently had been to a homeopath for the first time were interviewed to explore why parents take their children to homeopaths. All parents had been to a medical doctor before consulting the homeopath. It was the experiences with conventional medical treatment that led the parents to look for alternatives. The reasons were that 1) the parents did not want to give the medication prescribed by the doctor, 2) they wanted treatment while waiting for a problem to be assessed, 3) they did not want to continue to use the prescribed medication, 4) they stopped taking conventional medication due to side effects or 5) they were not offered any treatment by the medical doctor. The parents would consult a medical doctor if they felt insecure about the health conditions of the child and would visit a homeopath when they felt that the situation was clarified. There are parents who take their child to homeopaths despite not understanding or having belief in whether ultramolecular homeopathic medicines can have effects. One hundred and sixty-one children who had been diagnosed with an URTI by a medical doctor were recruited to participate in a trial on the effect of treatment by homeopaths for prevention of URTI in children. The children were randomly allocated to two groups. One group received an appointment immediately with one of five homeopaths who treated the patients as they do in their everyday practice. The other group (control) got such treatment after three months. The occurrence of URTI judged by the parents were significantly lower among those treated immediately by homeopaths (median 8 days in three months) compared to the control group who used self-selected conventional health care (median 13 days) (p=0.006). Homeopathic medicines are frequently used for self-treatment (over the counter-OTC). It is not known if the choice of the patient is the same, as a homeopath would have prescribed. A study was therefore conducted to explore if there can be developed indications for homeopathic medicines that facilitate that parents can chose the same medicine as a homeopath would prescribe for children with URTI. Firstly, data from a survey was used to find three medicines Calcarea carb, Pulsatilla and Sulphur that accounted for 60% of all prescription made by Norwegian homeopaths for children with URTI. Simplified constitutional indications for these medicines were developed and tested by comparing the choices of 70 parents with the prescription of eleven homeopaths. The parents were able to choose the same homeopathic medicine as homeopaths prescribed for 55% of the children. Two hundred and fifty-nine children who had been diagnosed with an URTI by a medical doctor were recruited to participate in a trial on the effect of one of three self-selected ultramolecular homeopathic medicines for prevention of URTI in children. The indications developed were used. The children was randomly allocated to receive either ultramolecular homeopathic medicine (C-30) or placebo. There was no difference in the occurrence of URTI judged by the parents among getting ultramolecular homeopathic medicine compared to those getting placebo (median 9 days in three months for both groups) (p=0.531). / Hensikten med denne avhandlingen er å undersøke hvorfor foreldre tar sine barn med til homøopat og å undersøke effekten av homøopatisk behandling i forebygging av øvre luftveisinfeksjoner (ØLI) hos barn. Bakgrunnen for de undersøkelsene som er gjort, er at det nesten er en tredobling i andelen barn blant pasienter hos homøopat. Dette utløste spørsmål om hvorfor det er slik. Videre er gjentatte luftveisplager en hovedårsak til at barn oppsøker homøopat. Fordi det er lite forskning på dette temaet ble spørsmålet om effekten av homøopatisk behandling i denne pasientgruppen også utløst. Avhandlingen bygger på fire ulike undersøkelser som er gjennomført mellom august 2002 og juni 2004. Foreldre til ni barn som nylig hadde vært hos homøopat for første gang ble intervjuet for å undersøke hvorfor foreldre tar sine barn med til homøopat. Alle foreldrene hadde vært hos lege før de kontaktet homøopaten, og det var erfaringer med legebehandlingen som fikk foreldrene til å søke alternativer. Årsakene var at foreldrene 1) ikke ønsket å gi den behandlingen lege foreskrev til barnet, 2) ønsket behandling mens barnet ventet på å bli ferdig utredet, 3) ønsket å avslutte bruken av de medisinene legen hadde foreskrevet for barnet, 4) opplevde at barnet fikk bivirkninger av behandlingen legen hadde gitt og 5) ikke ble tilbudt noen behandling hos legen. Foreldre oppsøker først lege når de er usikre eller bekymret for barnets helsetilstand. De oppsøker homøopat for behandling når dette er avklart. Det er foreldre som oppsøker homøopat med sine barn selv om de ikke forstår eller tror på effekten av homøopatiske medisiner (som kan være svært fortynnet). Ett hundre og sekstini barn som hadde vært til lege på grunn av en øvre luftveisinfeksjon ble rekruttert til å være med på en undersøkelse av effekten av behandling hos homøopat i forebyggingen av ØLI hos barn. Barna ble tilfeldig fordelt i to grupper. Barna i den ene gruppen fikk time med en gang hos en av fem homøopater som foreskrev homøopatisk behandling på vanlig måte. Den andre gruppen fikk slik behandling etter 3 måneder. Forekomsten av ØLI Hensikten med denne avhandlingen er å undersøke hvorfor foreldre tar sine barn med til homøopat og å undersøke effekten av homøopatisk behandling i forebygging av øvre luftveisinfeksjoner (ØLI) hos barn. Bakgrunnen for de undersøkelsene som er gjort, er at det nesten er en tredobling i andelen barn blant pasienter hos homøopat. Dette utløste spørsmål om hvorfor det er slik. Videre er gjentatte luftveisplager en hovedårsak til at barn oppsøker homøopat. Fordi det er lite forskning på dette temaet ble spørsmålet om effekten av homøopatisk behandling i denne pasientgruppen også utløst. Avhandlingen bygger på fire ulike undersøkelser som er gjennomført mellom august 2002 og juni 2004. Foreldre til ni barn som nylig hadde vært hos homøopat for første gang ble intervjuet for å undersøke hvorfor foreldre tar sine barn med til homøopat. Alle foreldrene hadde vært hos lege før de kontaktet homøopaten, og det var erfaringer med legebehandlingen som fikk foreldrene til å søke alternativer. Årsakene var at foreldrene 1) ikke ønsket å gi den behandlingen lege foreskrev til barnet, 2) ønsket behandling mens barnet ventet på å bli ferdig utredet, 3) ønsket å avslutte bruken av de medisinene legen hadde foreskrevet for barnet, 4) opplevde at barnet fikk bivirkninger av behandlingen legen hadde gitt og 5) ikke ble tilbudt noen behandling hos legen. Foreldre oppsøker først lege når de er usikre eller bekymret for barnets helsetilstand. De oppsøker homøopat for behandling når dette er avklart. Det er foreldre som oppsøker homøopat med sine barn selv om de ikke forstår eller tror på effekten av homøopatiske medisiner (som kan være svært fortynnet). Ett hundre og sekstini barn som hadde vært til lege på grunn av en øvre luftveisinfeksjon ble rekruttert til å være med på en undersøkelse av effekten av behandling hos homøopat i forebyggingen av ØLI hos barn. Barna ble tilfeldig fordelt i to grupper. Barna i den ene gruppen fikk time med en gang hos en av fem homøopater som foreskrev homøopatisk behandling på vanlig måte. Den andre gruppen fikk slik behandling etter 3 måneder. Forekomsten av ØLI var signifikant lavere hos de som fikk behandling hos homøopat med én gang (median 8 dager på tre måneder) sammenlignet med den andre gruppen som brukte standard behandling ved behov mens de ventet (median 13 dager) (p=0,006). Homøopatisk medisin brukes internasjonalt i stor grad til selvbehandling. Man vet ikke om pasientens eget valg av homøopatisk medisin er lik det en homøopat ville foreskrevet. Det ble derfor gjennomført en undersøkelse av om det kan utvikles beskrivelser for indikasjoner for homøopatiske medisiner som gjør at foreldre kan velge samme medisin som en homøopat foreskriver for barn med ØLI. Først ble det funnet fram til tre medisiner, Calcarea carb, Pulsatilla og Sulphur som homøopater i Norge foreskriver til 60% av barn med ØLI. Så ble det utviklet indikasjoner for disse tre medisinene som ble testet ut ved at valgene til 70 foreldre ble sammenlignet med foreskrivingen til 11 homøopater. Foreldrene valgte samme medisin som homøopaten for 55% av barna. To hundre og femtien barn som hadde vært til lege på grunn av en øvre luftveisinfeksjon ble rekruttert til å være med på en undersøkelse av effekten av en av tre selvvalgte homøopatiske medisiner i forebyggingen av ØLI hos barn. Indikasjonene som ble utviklet ble brukt. Barna ble tilfeldig fordelt til enten å få homøopatisk medisin eller placebo. Det var ingen signifikant forskjell i forekomsten av ØLI mellom de som fikk homøopatisk medisin sammenlignet med de som fikk placebo (median 9 dager på tre måneder i begge grupper) (p=0,531).

Chromosomal abnormalities are defined as changes in the chromosome structure and fall in one of two categories. The first category is numerical alterations while the second category consists of structural abnormalities. Structural chromosomal abnormalities do not always interrupt genes in order to cause disease. They can also affect gene expression by separating a gene and its promoter element from distant regulatory elements. We have used characterisation of structural chromosomal abnormalities to identify the genetic bases for several congenital disorders. In papers I-III, we have applied molecular characterisation of chromosomal translocations in order to identify candidate genes involved in mental retardation, hypospadias and anal malformation and premature ovarian failure. In paper I, we localised the chromosome X translocation breakpoint in a t(X;15) to be in the immediate proximity of the gene ZDHHC15 in a patient with severe mental retardation. Subsequent experiments revealed loss of ZDHHC15 transcription in the patient which suggests this gene to be involved in the aetiology of the patient’s phenotype. In paper II, we show that a balanced translocation between chromosomes 6 and 17 in a patient with urogential malformation disrupts 2 genes, one at each translocation breakpoint. We also identified a fusion-gene as a result of the translocation. Our hypethesis is that the translocation together with its molecular consequences is important for the phenotype in the patient. Similarly, in paper III, we have used molecular characterisation of the breakpoints in a balanced translocation between chromosomes X and 11 in order to localise candidate genes in ovarian function. Our results indicate a number of genes affected by the translocation. In paper IV, we have used array-based comparative genomic hybridisation (array-CGH) in order to investigate a cohort of autistic sib-pairs for submicroscopic chromosomal alterations. We have identified several novel duplications and one novel deletion with strong association with autism.

Management of wolves is a complex issue, and molecular genetics is an important tool in this work. Molecular genetics can provide important information at the species, population and individual level, which can be essential for the development of management programs aiming at the long term survival of wolf populations. In this thesis I developed new genetic markers on the canine Y chromosome to estimate the number of founders of the Scandinavian wolf population. This knowledge is important to reconstruct the history of the population and to design the most appropriate conservation strategies. Next, genetic markers with different pattern of inheritance have been used to identify hybrids between wolves and dogs. This allowed us to determine the direction of hybridization and to evaluate its possible impact on the gene pool of a wolf population. Furthermore, I also developed a method for a more reliable identification of the predator responsible of an attack by using saliva remains left on the prey. Since predation on livestock is perhaps the main reason for the negative opinions about the predator, the correct identification of the responsible for an attack (wolf, dog or hybrid) is essential. Finally, this thesis has also been focusing on the domestication of dogs. By using Y chromosome markers (paternally inherited), it has been possible to complement previous studies based on mtDNA sequences (maternally inherited) and autosomal markers (inherited from both parents). In this way I have obtained a more complete picture of the domestication process and of the origin of breeds. This has shown that there has been a bias in the contribution of the two sexes in the origin of dog breeds (fewer males then females contributing to each breed) and that the origin of dogs was not marked by extensive backcrosses with male wolves over the entire species range.

Non-coding antisense RNAs have been implicated in the epigenetic silencing of individual gene as well as chromosomal domains. While silencing of the overlapping gene by antisense RNAs has been well investigated, their functional role in silencing of chromosomal domains remains enigmatic. To elucidate mechanisms underlying the non-coding RNA mediated epigenetic silencing of chromosomal domains, we have chosen an antisense non-coding RNA, Kcnq1ot1, as a model system. Previously, a functional role of Kcnq1ot1 RNA and/or its transcriptional process has been implicated in silencing of multiple genes in the Kcnq1 imprinted cluster. However, these studies could not rule out the mechanisms involving other than Kcnq1ot1 RNA. Furthermore, it was also unclear how the Kcnq1ot1 promoter escapes silencing when its encoded RNA is capable of silencing flanking genes in cis. We have shown that NF-Y transcription factor plays a central role in the Kcnq1ot1 promoter activity, and that mutation of the NF-Y binding sites not only resulted in loss of silencing of flanking genes but also the ability of the Kcnq1ot1 promoter to protect against repressive chromatin marks, indicating that NF-Y maintains transcription-competent chromatin at the promoter through resisting the strong silencing effects of Kcnq1ot1 RNA. The Kcnq1ot1 RNA is an RNA Polymerase II encoded 91 kb long moderately stable nuclear transcript. We have demonstrated that it is the RNA not the act of transcription responsible for silencing and that the degree of silencing was proportional to the length of Kcnq1ot1 RNA. The kinetics of heterochromatin formation in relation to Kcnq1ot1 transcription revealed that overlapping gene was silenced initially by occlusion of basal transcription machinery and heterochromatin formation, whereas nonoverlapping gene was silenced subsequently by Kcnq1ot1-mediated heterochromatin spreading. This transcriptional silencing by Kcnq1ot1 RNA is mediated by an 890 bp region through promoting its interaction with the chromatin. Interestingly, we show that Kcnq1ot1 RNA establishes heterochromatin structures in a lineage-specific fashion by interacting with chromatin and chromatin remodelling complexes such as G9a and PRC2 complexes. More importantly, one of the parental chromosomes comprising Kcnq1 domain always found in the vicinity of perinucleolar region. Based on these data we proposed a mechanism whereby Kcnq1ot1 RNA establishes transcriptional silencing through recruitment of chromatin remodelling machinery and the maintenance of silencing achieved via targeting to the perinucleolar region.

The aim of this thesis has been to identify genetic variants that increase the susceptibility for Systemic Lupus Erythematosus (SLE), an autoimmune disease caused by a complex interplay between various genetic and environmental factors. Five different candidate genes were selected through different strategies, and were analysed for association with SLE in an attempt to distinguish some of the underlying mechanisms of this disease. Two of these genes, PD-L1 and PD-L2, appeared not to contain any major risk factors for SLE in the analysed European and Latin American populations. In two other genes, CD24 and STAT4, there appeared to be population-specific effects. The A57V amino acid substitution in the CD24 gene, previously implicated with multiple sclerosis, was associated in a Spanish cohort, with a weak trend in German samples, and no association in Swedish. The previously reported and highly convincing association of the STAT4 transcription factor gene was confirmed in all our cohorts. Interestingly, the results indicate the presence of at least two independent risk variants: the first, represented by a previously reported SNP, was the strongest in individuals of Northern European ancestry, and the second was more pronounced in individuals from Southern Europe and Latin America. We also report the identification of a novel susceptibility gene. The BANK1 gene, encoding a scaffold protein involved in B-cell activation, contains functional variants affecting important domains, which are associated in all investigated cohorts from Europe and Latin America. These results confirm the existence of replicable associations between genetic variants and SLE, which are common and present in many populations. The results also illustrate a certain degree of heterogeneity, where some risk factors could have variable effect in different populations.

Diamond-Blackfan anemia (DBA) is a severe congenital anemia characterized by a defect in red blood cell production. The disease is associated with growth retardation, malformations, a predisposition for malignant disease and heterozygous mutations in either of the ribosomal protein (RP) genes RPS7, RPS17, RPS19, RPS24, RPL5, RPL11 and RPL35a. In a cellular model for DBA, siRNA knock-down of RPS19 results in a relative decrease of other ribosomal (r) proteins belonging to the small subunit (RPS20, RPS21, RPS24) when compared to r-proteins from the large ribosomal subunit (RPL3, RPL9, RPL30, RPL38). RPS19 mutant cells from DBA patients show a similar and coordinated down-regulation of small subunit proteins. The mRNA levels of the small subunit r-proteins remain relatively unchanged. We also show that RPS19 has an extensive number of transcriptional start sites resulting in mRNAs of variable 5’UTR length. The short variants are translated more efficiently. Structural sequence variations in the 5’UTR of RPS19 found in DBA patients show a 20%-30% reduced translational activity when compared to normal transcripts. Primary fibroblast from DBA patients with truncating mutations in RPS19 or RPS24 showed specific cell cycle defects. RPS19 mutant fibroblasts accumulate in the G1 phase whereas the RPS24 mutant cells show a defect in G2/M phase. The G1 phase arrest is associated with a reduced level of phosphorylated retinoblastoma (Rb) protein, cyclin E and cdk2 whereas the G2/M phase defect is associated with increased levels of p21, cyclin E, cdk4 and cdk6. RPS19 interacts with PIM-1 kinase. We investigated the effects of targeted disruptions of both Rps19 and Pim-1 in mice. Double mutant (Rps19+/-, Pim-1-/-) mice have increased peripheral white- and red blood cell counts when compared to the wild-type mice (Rps19+/+, Pim-1+/+). Bone marrow cells in Rps19+/-, Pim-1-/- mice showed up-regulated levels of c-Myc and the anti-apoptotic factors Bcl2, Bcl-xl and Mcl-1 and reduced levels of the apoptotic factors Bak and Caspase 3 as well as the cell cycle regulator p21. In summary, this thesis clarifies several mechanisms in the pathogenesis of DBA. Mutations in RPS19 results in coordinated down-regulation of several small subunit r-proteins causing haploinsufficiency for the small ribosomal subunit. RPS19 have multiple transcriptional start sites and mutations in the RPS19 5’UTR found in DBA patients result in reduced translational activity. At the cellular level, mutations in RPS19 and RPS24 cause distinct cell cycle defects and reduced cell proliferation. Finally, PIM-1 kinase and RPS19 cooperates in the proliferation of myeloid cells.

The transition to flowering is a major developmental switch in angiosperms, the timing of which is expected to be important for fitness. In this thesis the focus has been on identification of genes affecting natural variation in flowering time in Brassica nigra. The background for this thesis is an earlier QTL-mapping study in B. nigra. The genomic area with the greatest effect on flowering time in that study contained a homolog to the CONSTANS gene, which is known to affect flowering time in A. thaliana. When studied more closely this gene did not seem to affect flowering time variation in B. nigra. Near the B.nigra CO gene (BniCOa), however, we identified a homolog to the related CONSTANS LIKE 1 (COL1) gene. In A. thaliana COL1 has not been shown to be associated with induction of flowering but since the B. nigra homolog (BniCOL1) in the QTL area showed surprising amounts of variation between early and late flowering plants we set out to test if this variation was associated with flowering time variation. In the first paper we found a significant association between flowering time and one indel (Ind2) in the coding region. Motivated by the results in paper one, we searched for evidence of selection at the BniCOL1(paper two). In paper three the aim was to validate the results from the first paper in a larger sample of populations, and to check whether the association found in paper I could reflect linkage disequilibrium with areas outside of the gene. Finally, in paper four we investigate the general evolution of three CONSTANS-LIKE genes in B. nigra, namely BniCOL1, BniCOa and BniCOb.