<p>Angiogenesis is defined as the formation of new capillary blood vessels from pre-existing ones. This process involves several steps including: migration, proliferation and differentiation of endothelial cells into blood vessels. Angiogenesis is initiated by binding of specific growth factors, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF), to their cell surface receptors. Shb is a ubiquitously expressed adaptor protein with the ability to bind several tyrosine kinase receptors. My aim has been to identify the role of Shb in FGF- and VEGF-signalling in endothelial cells. Shb was found to be phosphorylated in a Src-dependent manner upon both FGF- and VEGF-stimulation. This was confirmed using fibroblasts overexpressing temperature sensitive v-Src. Furthermore, Shb-induced cell spreading on collagen of immortalised brain endothelial (IBE) cells was also Src-dependent. FGF stimulation led to a direct association between Shb and FAK, which was mediated by the phosphotyrosine binding domain of Shb. IBE cells overexpressing wild-type or R522K Shb (inactive SH2 domain) displayed increased FAK activation on collagen.</p><p>The SH2-domain of Shb was found to bind to tyrosine 1175 in the VEGFR-2 in a phosphotyrosine dependent manner using PAE cells expressing VEGFR-2. Furthermore, by use of siRNA, Shb knock-down experiments revealed that Shb regulates FAK activity, cellular migration and stress fiber formation in response to VEGF stimulation of VEGFR-2. In summary, Shb binds to both FGFR-1 and VEGFR-2 and regulates the activity of FAK and thereby stress fiber formation and cellular migration, which are necessary for formation of new blood vessels. IBE cells with an inactive SH2 domain of Shb displayed disorganised formation of tubular structures in the tube formation assay, while overexpression of wild-type Shb led to accelerated tubular morphogenesis.</p><p>Taken together, my data show that the adaptor protein Shb plays an important role in the process angiogenesis, in response to angiogenic tyrosine kinase receptors, by interacting with FAK and regulating spreading, stress fiber formation and cellular migration.</p>

<p>This thesis evaluates the use of Fourier Transform Infrared Spectroscopy (FTIR) as an approach to the increasingly difficult air sampling challenges within the field of occupational and environmental hygiene. The application of FTIR is exemplified by the assessment of emissions from and exposures in the sawmill and pellet industries. </p><p>Open path FTIR was applied in the sawsheds and the terpene levels were monitored for several days. Traditional adsorbent sampling was used to evaluate the FTIR measurements. The volatile emissions from wood pellets were investigated in warehouses and in domestic storage rooms. </p><p>The installation of open path FTIR in the harsh sawmill environment proved useful, however, attention must be paid to vibrations, beam blockage and limited sensitivity. Adsorbent sampling showed good agreement with open path FTIR. The uncontrolled airflows in sawsheds caused significant underestimation of emission rates. By the use of FTIR and a tracer gas a more accurate estimate was obtained. The total emission from processing of Scots pine was estimated to 660 g/m³ of roundwood under bark, and can amount to 700 tons annually from a large sawmill.</p><p>Hexanal (111±32 mg/m³) and CO (56±4mg/m³) were recorded in pellet warehouses. Storage of wood pellets constitutes a potential occupational and domestic health hazard. Experiments from kiln drying of lumber show that the emissions of hexanal and carbon monoxide are not limited to wood pellets but are caused by general degradation processes of wood, facilitated by drying at elevated temperature. This is the first published report where low-temperature emission of carbon monoxide from wood materials is described. </p><p>The FTIR method is a significant advancement in measurement technology. The retrieved data offers unparalleled information. It offers robust, convenient and efficient monitoring of gases over extended periods. FTIR spectroscopy should be considered a standard technique within the field of occupational and environmental hygiene.</p>

<p>Domestication has led to genetic changes that affect quantitative traits in farm animals. Both candidate gene analysis using association tests and genome scans based on linkage analysis have been performed to understand the molecular basis underlying quantitative genetic variation in horses, pigs and chickens. To test a possible association of polymorphisms in the <i>PRKAG3</i> gene, previously found to be associated with excess glycogen content in pig skeletal muscle, with quantitative traits in the horse, the major coding part of the equine <i>PRKAG3</i> sequence was identified. Bioinformatic characterization of the equine <i>PRKAG3</i> gene was conducted. A single nucleotide polymorphism (SNP) causing a missense mutation (Pro258Leu) was found. Screening this SNP showed that the Leu258 allele was more frequent in breeds with heavy muscularity. To assess previously reported associations between polymorphisms in the <i>MC4R</i> gene and obesity-related traits further, we conducted linkage analysis between the <i>MC4R</i> locus and fatness-related traits using a Wild BoarxLarge White intercross. No significant association between segregation at the <i>MC4R</i> locus and fatness was detected in this pedigree. A genome scan of quantitative trait loci (QTLs) has been performed in an intercross between chicken lines divergently selected for growth. Divergent parental lines have been established by selecting for high and low 56-day body weight for over 40 generations. The selection has led to approximately a 9-fold difference in 56-day body weight between lines and resulted in correlated responses for a number of traits including appetite, immune response, body composition and metabolic traits. Phenotypic data on growth and other correlated traits were collected from more than 800 F2 individuals. Genome scans using 145 markers on 26 linkage groups have identified QTLs affecting growth and correlated responses to selection for 56-day body weight. No major QTL explaining a large portion of phenotypic variation in growth was revealed in this study. </p>

<p><i>Objectives.</i> To study the prevalence of musculoskeletal symptoms among farmers as compared to rural referents and to evaluate the effects of physical work exposures, psychosocial factors, lifestyle and comorbidity.</p><p><i>Material and methods.</i> A cross-sectional population-based survey of 1013 farmers and 769 matched referents was performed. Data on various symptoms, consultations and sick leave and information on primary health care and hospital admissions were obtained along with information on physical workload, psychosocial factors and lifestyle. </p><p><i>Results.</i> The farmers reported higher lifetime prevalence of symptoms from hands and forearms, low back and hips as compared to the referents. However, the farmers did not seek medical advice more often than the referents, and they reported significantly fewer sick leaves. After adjustment for the influence of physical work exposure, farmers still had a excess rate of low back pain (LBP) and hip symptoms as compared with the referents, while a lower rate of neck-shoulder symptoms was revealed. Several of the psychosocial variables were associated with LBP but the difference in LBP prevalence between farmers and referents could only be explained to some extent. LBP was associated with musculoskeletal symptoms other than LBP and with chest discomfort, dyspepsia, symptoms from mucous membranes, skin problems, work-related fever attacks, and primary care for digestive disorders. Presence of both respiratory and digestive disorders doubled the LBP prevalence.</p><p><i>Conclusions.</i> Symptoms from hips and low back were more frequent among farmers than among referents, but farmers did not seek more health care and reported fewer sick leaves than referents. Physical work exposure and psychosocial factors did not explain the differences in low back and hip symptoms between the two groups. Significant associations between LBP and digestive and respiratory disorders might indicate that these disorders may have etiological factors in common.</p>

<p>Postmenopausal estrogen therapy, initiated early in the menopause, seems to protect against development of atherosclerosis and cardiovascular diseases. This thesis concerns studies of artery wall thickness and arterial stiffness estimated by noninvasive ultrasound techniques in long-term estrogen treated postmenopausal women who initiated therapy at the time of the menopause.</p><p>A noninvasive 25 MHz high-frequency ultrasound technique was validated in the imaging of superficial arteries by using an animal model. Ultrasound estimates of the artery wall layers obtained <i>in vivo</i> in the pig were compared to <i>ex-vivo</i> histomorphometry. Valid estimates of total artery wall and media thickness were found for the most superficial arteries. Adventitia thickness was underestimated and intima thickness overestimated in this animal model when non-atherosclerotic vessels were imaged.</p><p>To validate the clinical usefulness of separately estimating the artery wall layers in the human, the carotid artery wall was imaged in elderly subjects. Separate estimates of intima thickness, media thickness and intima/media ratio differed significantly between subjects with and without atherosclerosis and CVD, indicating that this noninvasive high-frequency ultrasound method might be a strong tool in monitoring changes in artery wall morphology associated with aging and development of atherosclerosis.</p><p>The investigation of intima thickness, media thickness and intima/media ratio of the carotid and femoral arteries in long-term estrogen treated postmenopausal women showed a maintenance of a thin intima and a preservation of media thickness and intima/media ratio at values similar to those obtained in women of fertile age. By comparing estrogen-users with age-matched postmenopausal nonusers, long-term estrogen therapy initiated at the time of the menopause seemed to counteract the increase in intima and decrease in media thickness associated with aging and development of atherosclerosis. The preservation of the artery wall morphology into older age might be a mechanism for the well-documented cardioprotective effects of estrogen when therapy is initiated early after menopause. However, long-term estrogen therapy showed no substantial effects on the age-related changes in arterial stiffness estimated at the aorta, carotid and femoral arteries, suggesting that any long-term cardioprotective effect that estrogen therapy may have is unlikely to be mediated by an impact on arterial stiffness. </p>

<p>Patients with rheumatoid arthritis (RA) are at increased risk of developing malignant lymphoma, although details about this association remain unclear. The aims of this thesis were to investigate risk factors for lymphoma in patients with RA and to characterize these lymphomas regarding subtype, presence of Epstein-Barr virus (EBV), clinical manifestations and prognosis. </p><p>The Swedish hospital discharge register and the cancer register were used to identify RA patients with lymphoma. Two case-control studies were performed, one smaller including RA patients with lymphoma hospitalised in Uppsala health care region 1964-1983 (n=41) and one larger study of hospitalised RA patients with lymphoma in Sweden 1964-1995 (n=378). RA patients from the same cohorts, but without lymphoma, were matched as controls. Medical records for cases and controls were scrutinized for exposure information. The lymphoma tissues were reclassified according to the WHO classification, and presence of EBV was analysed by EBER in situ hybridisation.</p><p>The most important risk factor for lymphoma development was high RA disease activity. No association was determined between treatment with traditional disease modifying drugs, non-steroidal anti-inflammatory drugs, aspirin, peroral and intra-articular corticosteroids and lymphoma risk. Diffuse large B-cell lymphoma (DLBCL) was more frequent in RA patients than in lymphoma patients in the general population and displayed stronger association with RA disease activity than other lymphoma subtypes. RA patients with DLBCL had increased extranodal involvement and more advanced lymphoma stage at presentation than DLBCL patients in general, and the prognosis was poor. </p><p>A further subdivision of DLBCL into germinal centre (GC) and non-GC subtypes by the expression patterns of CD10, bcl-6 and IRF-4 showed a predominance of the non-GC subtype. This suggested peripheral activated B-cells as the cells of origin in these lymphomas. </p><p>The presence of EBV was low in lymphomas in RA patients (12%). </p>

<p>IgG, IgM and IgE in complex with antigen have the capacity to regulate specific immune responses. In this investigation, the role of Fc receptors for IgG (FcγRI, FcγRII and FcγRIII) and complement receptors 1 and 2 (CR1/2) for antibody-mediated enhancement of antibody responses are investigated.</p><p>IgM is known to efficiently activate complement and thereby enhance specific antibody responses but it is not known if this involves binding to CR1/2. Using CR1/2 deficient mice, immunized with sheep erythrocytes alone or together with specific IgM, we present evidence that IgM-mediated enhancement is completely dependent on CR1/2 expression, whereas IgG or IgE in complex with bovine serum albumin (BSA) induce strong antibody responses in CR1/2-deficient mice. Enhancement by IgE is mediated via the low affinity receptor for IgE (FcεRII, CD23). However, the receptors which are involved in IgG-mediated enhancement are not known. We find that γ-chain-deficient mice (lacking FcγRI and FcγRIII) have impaired antibody responses to IgG/BSA complexes. In contrast, FcγRIII deficient mice have normal responses, suggesting that FcγRI mediates the effect. Furthermore, IgG/BSA complexes induce up to 189-fold stronger antibody responses in FcγRIIB-deficient mice than in wild-type mice. The threshold dose of IgG/BSA required was lower, the response was sustained for longer and initiated earlier in FcγRIIB-deficient than in wild-type animals. The findings suggest that FcγRIIB acts as a "safety-valve" preventing excessive antibody production during an immune response. We show for the first time that IgG3/BSA complexes can mediate enhancement of specific antibody responses. Their effect does not involve known Fcγ receptors.</p>

<p>A diagnosis of coeliac disease (CD) in adults relies on the presence of a structurally abnormal intestinal mucosa, followed by a clear clinical remission on a gluten-free diet. There is a clear need for a rapid, simple, safe and sensitive method to determine the type and intensity of inflammation in the gut mucosa in clinical practice. The overall aims of our studies were to develop and evaluate a new technique, “the mucosal patch technique”, to characterize rectal local inflammatory process after rectal food challenge in patients with CD<b>. In study 1</b> we evaluated the potential of the new technique. The technique was well tolerated and easily applied. Pronounced neutrophil and eosinophil involvement in ulcerative colitis (UC) was demonstrated. With the high sensitivity of the technique, low-degree mucosal neutrophil activation could also be quantified in patients with collagen colitis,UC in clinical remission and in patients with irritable bowel syndrome. <b>In study 2 and 3</b> the aim was to elucidate the dynamics of the rectal inflammatory response and nitric oxide (NO) production after rectal gluten challenge. We found a pronounced neutrophil activation in coeliac patients after rectal gluten challenge. This activation was apparent 4 hours after challenge and remains for at least 48 hours. A more modest eosinophil activation started 1-2 hours later and remained at least for 48 hours. The biphasic pattern of neutrophil and eosinonphil activation after challenge suggests a biphasic inflammatory reaction. The activation of neutrophils and eosinophils precedes a pronounced enhancement of mucosal NO production. Some of our coeliac patients displayed signs of an inflammatory reaction after rectal corn gluten challenge. <b>In study 4</b> the aim was to investigate the local inflammatory reaction to gluten and cow’s milk protein in CD patients in remission. The findings indicate that not only gluten sensitivity but also cow’s milk (CM) protein sensitivity is common in CD. The data support the hypothesis that CM sensitivity may contribute to persistent symptoms in coeliac patients on gluten-free diet.</p>

<p>We evaluated, in patients with ST-elevation myocardial infarction (STEMI) treated with thrombolytics, admission Troponin T (tnT), ST-segment resolution and admission N-terminal pro-brain natriuretic peptide (NT-proBNP) for early risk stratification as well as time delays and outcome in real life patients according to prehospital or in-hospital thrombolytic treatment. Also, baseline characteristics, treatments and outcome in patients enrolled in the ASSENT-2 trial in Sweden and in patients not enrolled were evaluated. </p><p>TnT (n=881) and NT-proBNP (n=782) on admission and ST-resolution at 60 minutes (n=516) in patients from the ASSENT-2 and ASSENT-PLUS trials were analysed. Elevated levels of NT-proBNP and tnT on admission were both independently related to one-year mortality. However, when adding information on ST-resolution (</≥50%) 60 minutes after initiation of thrombolytic treatment, tnT no longer contributed independently to mortality prediction. High and low risk patients were best identified by a combination of NT-proBNP and ST-resolution at 60 minutes.</p><p>We investigated consecutive STEMI patients included in the RIKS-HIA registry between 2001 and 2004, if they were ambulance transported and had received prehospital (n=1690) or in-hospital (n=3685) thrombolytic treatment. Prehospital diagnosis and thrombolysis reduced the time to thrombolysis by almost one hour, were associated with better left ventricular function and fewer complications and reduced the adjusted one-year mortality by 30% compared with in-hospital thrombolysis. </p><p>Prospective data from the RIKS-HIA registry on STEMI patients treated with thrombolytics were linked to data on trial participants in the ASSENT-2 trial of thrombolytic agents and used for direct comparisons. Patients treated with thrombolytics and not enrolled in a clinical trial at trial hospitals (n=2048) had higher risk characteristics, more early complications and twice as high adjusted one-year mortality compared to those enrolled (n=729). One major reason for the difference in outcome appeared to be the selection of less critically ill patients to the trial.</p>

<p>Objectives. To describe the prevalence of asthma in a mid-Swedish region and measure the detection rate of asthma in primary care. To compare clinical outcomes for adolescents with asthma in primary care or in paediatric care and to perform a clinical validation in children with airway, nose and skin symptoms.</p><p>Material and methods. A questionnaire survey of respiratory symptoms and disease in an adult population and an investigation of the occurrence of clinically detected asthma in primary care. A cross-sectional study comparing management, asthma control and quality of life in adolescents. The last study was a nested case-control study with a clinical validation of reported allergic symptoms in children.</p><p>Results. The prevalence of asthma in the adult population was 8%. The clinical prevalence of asthma in primary care was 2%. The detection rate was higher in primary health care centres with asthma clinics, as compared to primary care without such clinics. In adolescents with asthma there was no difference in clinical outcomes between primary care and paediatric care. The validation study showed a high correlation between assigned cases and disease. </p><p>Conclusions. Asthma is a common disease where the majority of cases are managed in primary care. Many cases are, however, not diagnosed and the detection rate becomes a quality care indicator. The study of adolescents confirms that proactive care can be further improved regardless of whether their management is in primary or paediatric care. The nested case-control design is suitable to suggest causational risk factors for asthma and for prediction of allergic disease development.</p>