Circulating immune complexes play an important role in the modulation of antibody responses and in the pathogenesis of immune diseases. This thesis deals with the in vivo regulatory properties of antibodies and their specific Fc receptors. The immunosuppressive function of IgG is used clinically, to prevent rhesus-negative women from becoming sensitized to rhesus-positive erythrocytes from the fetus. The mechanism behind this regulation is poorly understood but involvement of a receptor for IgG, FcγRII, has been suggested. It is shown in this thesis that IgG and also IgE induce immunosuppression against sheep erythrocytes to a similar extent both in mice lacking all the known Fc receptors as in wild-type animals. These findings imply that antibody-mediated suppression of humoral responses against particulate antigens is Fc-independent and that the major operating mechanism is masking of epitopes. Immunization with soluble antigens in complex with specific IgG leads to an augmentation of antibody production. The cellular mechanism behind this control is examined here and it is found that the capture of IgG2a immune complexes by a bone marrow-derived cell expressing FcγRI (and FcγRIII) is essential. An analysis of the ability of IgG3 to mediate this regulation indicated that, in contrast, this subclass of IgG augments antibody responses independently of FcγRI (and FcγRIII). These findings suggest that distinct mechanisms mediate the enhancing effect of different subclasses of antibodies. Finally, the contribution of FcγRIII was studied in the development of collagen-induced arthritis (CIA), an animal model for rheumatoid arthritis in humans. It was discovered that while DBA/1 wild-type control mice frequently developed severe CIA, with high incidence, FcγRIII-deficient mice were almost completely protected, indicating a crucial role for FcγRIII in CIA. The results presented here help to understand how immune complexes regulate immune responses in vivo and show that Fc receptors for IgG, if involved, could be new targets for the treatment of immune complex-related disorders.

Thyroid growth and function is partly regulated by growth factors binding to receptors on the cell surface. In the present thesis, the transforming growth factor-β (TGF-β) superfamily members have been studied for their role in regulation of growth and differentiation of both normal and neoplastic thyroid epithelial cells. TGF-β1 is a negative regulator of thyrocyte growth and function. However, the importance of other TGF-β superfamily members has not been fully investigated. TGF-β1, activin A, bone morphogenetic protein (BMP)-7 and their receptors were found to be expressed in porcine thyrocytes. In addition to TGF-β1, activin A was also found to be a negative regulator of thyroid growth and function, and both stimulated phosphorylation and nuclear translocation of Smad proteins. Furthermore, TGF-β1 and epidermal growth factor (EGF) demonstrated a synergistic negative effect on thyrocyte differentiation. Simultaneous addition of the two factors resulted in a loss of the transepithelial resistance and expression of the epithelial marker E-cadherin. This was followed by a transient expression of N-cadherin. Despite the extremely malignant character of anaplastic thyroid carcinoma (ATC) tumor cells, established cell lines are still responsive to TGF-β1. A majority of the cell lines were also found to be growth inhibited by BMP-7. BMP-7 induced cell cycle arrest of the ATC cell line HTh 74 in a dose- and cell density-dependent manner. This was associated with upregulation of p21CIP1 and p27KIP1, decreased cyclin-dependent kinase (Cdk) activity and hypophosphorylation of the retinoblastoma protein (pRb). TGF-β1, and to some extent also BMP-7, induced the expression of N-cadherin and matrix metalloproteinase (MMP)-2 and -9. Stimulation of HTh 74 cells with TGF-β1 increased the migration through a reconstituted basement membrane indicating an increased invasive phenotype of the cells. Taken together, these data show that TGF-β superfamily members not only affect growth and function of normal thyroid follicle cells but may also, in combination with EGF, play a role in cell dedifferentiation. This study additionally suggests that the TGF-β superfamily members may be important for the invasive properties of ATC cells.

3’ end cleavage and polyadenylation are important steps in the maturation of eukaryotic mRNAs. Poly(A) polymerase (PAP), the enzyme catalysing the addition of adenosine residues, exists in multiple isoforms. In this study the functional significance of multiple poly(A) polymerases have been investigated. It is concluded (i) that at least three mechanisms generate the multiple isoforms i.e. gene duplication, post-translational modification and alternative mRNA processing and (ii) that the different isoforms of poly(A) polymerases have different catalytic properties. The study highlights regulation of poly(A) polymerase activity through modulation of its affinity for the substrate as visualised by the KM parameter. We suggest that trans-acting factors modulating the KM of poly(A) polymerase will play important roles in regulating its activity. A new human poly(A) polymerase (PAPγ) encoded by the PAPOLG gene was identified. PAPγ is 65% homologous to the previously identified PAP. In human cells three isoforms of poly(A) polymerases being 90, 100 and 106 kDa in sizes are present. These native isoforms were purified. The PAPOLA gene encoded the 100 and 106 kDa isoforms while the 90 kDa isoform was encoded by the PAPOLG gene. Native PAPγ was found to be more active than 100 kDa PAP while the hyperphosphorylated 106 kDa PAP isoform was comparably inactive due to a 500-fold decrease in affinity for the RNA substrate. The PAPOLG gene was shown to encode one unique mRNA while the PAPOLA gene generated five different PAP mRNAs by alternative splicing of the last three exons. The PAPOLA encoded mRNAs were divided into two classes based on the composition of the last three exons. Poly(A) polymerases from the two classes were shown to differ in polyadenylation activities. These differences revealed two novel regulatory motifs in the extreme C-terminal end of PAP, one being inactivating and the other activating for polyadenylation activity.

Human endogenous retroviruses (HERVs) represent approximately 7% of the human genome. This investigation was focused on one particular HERV, ERV3, with the main purpose of characterising its gene expression patterns and genomic distribution of ERV3-like sequences. Furthermore, this careful expression study should provide insights into the biological role of HERVs. The impact of HERVs in health and disease is not yet clarified. ERV3 is expressed as three envelope (env) transcripts, of which two also contain a cellular gene, H-plk (human proviral linked Krüppel). ERV3 env expression was mainly investigated at the RNA level. The gene expression of two other HERVs, HERV-K and HERV-E was analysed and compared with ERV3 activity. Real-time PCRs were developed and in combination with in situ hybridisation, it was found that ERV3 is expressed in a tissue- and cell-specific way. High levels of ERV3 mRNA (up to six times over Histone3.3) were demonstrated in placenta, sebaceous glands, foetal and adult adrenal glands, brown adipose tissue, corpus luteum, pituitary gland, thymus and testis. In monocytic cells including both normal monocytes and malignant U-937 cells, elevated mRNA levels were observed after retinoic acid (RA)-induced differentiation. ERV3-encoded Env protein was detected in selected cases, one following RA-treatment. In addition, several new ERV3-like sequences were discovered in the human genome. ERV3 was found to have conserved open reading frames in contrast to other ERV3-like sequences in the human genome. This suggests that ERV3 may be involved in important cellular processes such as differentiation, cell fusion, immunomodulation and protection against infectious retroviruses. The developed techniques and obtained results will allow further studies of HERV expression to better correlate HERV activity to both normal development and disease.

The main purpose of this thesis was to apply the WHO and NHS palliative care approach to dementia care. Thirty-one staff-members in mid-Sweden (studies I and II) and 20 next-of- kin (study IV) were interviewed. In study III, 316 staff-members from dementia care and 121 staff-members from palliative cancer care responded to a questionnaire about family support. The interviews were tape-recorded and analysed with a qualitative phenomenographic (I and II) and a hermeneutic approach (IV). The questionnaires (III) were analysed using qualitative and quantitative content analysis. The staff-members stated almost unanimously that daily leadership was lacking, and consequently clear goal formulations and care planning were rare (I). Proper teamwork between the doctor and the staff who worked on a daily basis with the patients was absent (I). With respect to existential issues, education and staff discussions were lacking (II). The staff were at a loss concerning how to deal with these issues. Nevertheless, these issues are central to family-members who have to deal with an existential crisis (IV). Important questions emerged about obligation and guilt, faithfulness, responsibility, and paying back what you once received. Existential isolation could be identified e.g. in the reversal of roles experienced as "being a parent to your parent" and in the burden of "visiting a living dead person". There were no routines for bereavement visits. The type of support suggested for dementia family members is partly similar to support in palliative cancer care, but it also differs in other respects such as feelings of guilt because the early signs of the disease are misunderstood, the need for respite because of the long trajectory of dementia diseases, and the occurrence of anticipatory grief because in the late phase family members can no longer make any contact at all with the patient (III). A palliative approach can improve the quality of life for the dementia patient and for the family. It can be used as a basis for a clear goal formulation. Some of the suggestions listed in this thesis for improving the quality of care are more a reflection of the need for a change in attitudes rather than the need for substantial budget increases.

Heart failure and left ventricular dysfunction are major causes of morbidity and mortality. In this thesis, metabolic, hormonal, genetic and prognostic aspects of echocardiographically determined left ventricular function were investigated in a fairly large longitudinal population-based study of men. The participants were examined both at age 50 and 70 years and were followed for mortality using the national cause-of-death registry. Several factors associated with the insulin resistance syndrome predicted left ventricular systolic dysfunction independent of myocardial infarction, hypertension, diabetes and the use of cardiovascular medication after twenty years follow-up. Plasma levels of N-terminal atrial natriuretic peptide (N-ANP) were significantly increased in men with left ventricular dysfunction in comparison to healthy men. However, the diagnostic accuracy was poor due to the extensive overlapping between the groups. Relations between a haplotype of the novel hUNC-93B1 gene and the E/A-ratio were found and validated in separate samples of the cohort. Myocardial performance index (a Doppler derived index of combined left ventricular systolic and diastolic function) and left ventricular ejection fraction were found to be predictors for cardiovascular mortality independent of traditional cardiovascular risk factors in a longitudinal analysis with a mean follow-up of seven years. In conclusion, this thesis showed that left ventricular function is influenced by metabolic, hormonal and genetic factors and that echocardiographic measurements of left ventricular function, such as the myocardial performance index, are strong independent risk factors for cardiovascular mortality in elderly men.

Defects in insulin secretion and insulin action are the major abnormalities in the development of Type 2 diabetes. Hyperinsulinemia is a risk marker for Type 2 diabetes and according to some, but not in all studies also for coronary heart disease (CHD). Conventional insulin assays measure immunoreactive insulin including proinsulin-like molecules. Proinsulin and insulin measured by specific methods, insulin sensitivity measured by the euglycemic insulin clamp and early insulin response after a glucose challenge give more detailed information and may be better estimates of true risk for Type 2 diabetes and CHD. This study examined relationships between proinsulin, insulin, insulin secretion and insulin sensitivity for the development of Type 2 diabetes and CHD. The investigation of the prognostic significance of proinsulin and insulin for the development of Type 2 diabetes and CHD was performed in prospective studies of 50-year and 70-year-old men in a population-based cohort. The results indicated, that increased proinsulin concentrations, was a marker of increased risk for Type 2 diabetes independent of measurements of insulin secretion and insulin sensitivity whereas insulin was not. Proinsulin was shown to be a predictor for CHD mortality and morbidity, respectively, independent of conventional risk factors, whereas insulin was not. Insulin sensitivity measured by the gold standard euglycemic insulin clamp at age 70 was a predictor of CHD morbidity, independently of established risk factors. In summary, these data provide evidence that an increased concentration of proinsulin and not an elevated plasma insulin level per se, that constitutes the association with Type 2 diabetes and CHD and that insulin resistance per se, is associated with CHD risk. / Defekter i insulinsekretionen och insulinkänsligheten i målorganen för insulin är de huvudsakliga orsakerna till utvecklandet av typ-2 diabetes. Förhöjd insulinhalt i blodet indikerar nedsatt känslighet för insulin och är en riskmarkör för typ-2 diabetes men också för hjärt-kärlsjukdom enligt vissa studier. Konventionella insulinmätmetoder är ospecifika och mäter immunoreaktivt insulin som förutom insulin också innehåller ett förstadium till insulin, proinsulin. Proinsulin och specifikt insulin, insulinkänslighet bestämd med hyperglykemisk insulin clamp teknik och tidigt insulinsvar vid sockerbelastning ger en bättre och mer detaljerad och precis information. Dessa variabler kan därför utgöra en bättre prediktor för typ-2 diabetes och hjärt-kärlsjukdom. I denna avhandling har proinsulin, specifikt insulin, tidigt insulinsvar vid sockerbelastning och insulinkänslighet jämförts med varandra som prediktorer för utvecklandet av typ-2 diabetes och hjärt-kärlsjukdom. Två studier har omfattat risken för diabetes och två studier risken för hjärt-kärlsjukdom. Män i medelåldern respektive i högre ålder har studerats. Studierna har utförts i en populations-baserad grupp, en kohort som har sitt ursprung i en stor hälsoundersökning som genomfördes i Uppsala 1970 till 1973. Resultaten visar att proinsulin, i motsats till specifikt insulin, är en riskmarkör för utveckling av typ 2 diabetes, oberoende av insulinkänslighet och tidigt insulinsvar vid sockerbelastning. Vidare har visats att proinsulin i motsats till specifikt insulin är en riskmarkör för död respektive sjuklighet i hjärt-kärlsjukdom, oberoende av de kända riskfaktorerna rökning, högt blodtryck och förhöjt kolesterol. Slutligen har visats att insulinkänsligheten i sig är en riskmarkör för hjärt-kärlsjuklighet oberoende av ovanstående riskfaktorer förutom proinsulin. Sammanfattningsvis visar resultaten i avhandlingen att det snarare är proinsulinhalten och inte insulinnivån i blodet som står för de observerade sambanden med typ 2 diabetes och hjärt-kärlsjukdom. Nedsatt känslighet för insulin i sig är förenat med ökad risk för hjärt-kärlsjukdom.

Oncogenic human papillomaviruses (HPVs) are implicated in 99.7 % of cervical cancer cases but require the co-operation of other factors. To investigate potential genetic risk factors we have typed the HLA class II DRB1 and DQB1 loci in 478 women diagnosed with cervical carcinoma in situ and in 608 age-matched controls. Quantitative measurements of HPV 16, HPV 18/45 and HPV 31 were obtained. The DRB1*1501 and DQB1*0602 alleles were found to increase the risk of HPV 16 infection. Carriers of DRB1*1501 and DQB1*0602 were also shown to have an increased risk of a higher viral load compared to non-carriers. The DRB1*1301 and DQB1*0603 alleles were found to protect from HPV 18/45 and 31 infections as well as resulting in a lower viral load in carriers compared to non-carriers. Women with a high HPV 16, 18/45 or 31 viral load were more prone to long-term infections and women with a low HPV 16 viral load were more prone to short-term infections. Carriers of DRB1*1501 and DQB1*0602 alleles were also shown to have an increased risk of long-term infections compared to short-term infections. We also tested if an HPV susceptibility locus found for epidermodysplasia verruciformis (EV) was also linked to HPV susceptibility in cervical cancer. We did not find any linkage to this locus in a set of 77 families, each with at least three cases diagnosed with cervical carcinoma in situ. Other potential risk factors tested were HPV 16 E6 variants together with a p53 codon 72 polymorphism and HLA class II alleles. We found an association between the E6 L83V variant and the HLA DR4-DQ3 haplotype, as well as an increased frequency of Arg homozygosity of p53 in women infected with the L83V variant. These results show that alleles at HLA class II loci represents risk factors for persistent HPV infection and thereby also contribute to the risk of development of cervical carcinoma in situ.

The overall aim of this thesis was to evaluate the outcome when treating children for displaced femoral fractures with external fixation. In a consecutive and prospective study during the period 1993-2000, 96 children aged 3-15 years with 98 displaced femoral fractures were treated with external fixation and early mobilisation. The mean age was 8.1 years, the mean hospital stay was 8.7 days and the mean treatment time was 61 days. All fractures healed. Minor complications included pin tract infections (18%), clinical insignificant malunions, heterotopic ossification and two re-reductions. Major complications (6%) included two re-fractures after significant trauma and three plastic deformations after premature fixator removal leading to an osteotomy. Radiological evaluation was performed up to one year for the whole group and for a subgroup up to two years. The evaluation showed that malunions were few and prone to remodelling almost completely. Although the fractures were fixated without shortening, as recommended earlier, the overgrowth was far less than expected. Isokinetic muscle strength was measured in both hamstrings and quadriceps in 31 of the patients and compared with 31 matched children without previous injury to the legs. Early mobilisation seems to prevent residual muscle weakness previously shown after treatment with traction or cast for femoral fractures in children. A cost analysis was performed, comparing three different treatment modalities of femoral shaft fractures: traction in hospital, traction in hospital/at home and external fixation. The analysis included both total medical costs and costs for the care provider. The most important factors were days spent at the hospital and the sick leave for the care provider. Treatment that can minimise these factors will contribute strongly to a lowering of health care costs. Conclusion: External fixation of displaced femoral fractures in children can be used as standard treatment in children aged 3-15 years. The treatment provides satisfactory results with a low rate of major complications. Early mobilisation seems to prevent residual muscle weakness. The treatment reduce the number of days in hospital and the number of days of sick leave for the care provider and contributes strongly to lowering health care costs.

This dissertation has two parts. Firstly, satisfaction with life as a whole and with 10 life domains (using an instrument termed LiSat-11 with 6-graded scales) is described in a nationally representative sample aged 18-64 years (n: 2,533) and is related to some socio-demographic circumstances. Secondly, vocationally disabled people (n: 109) at an employability institute are prospectively followed in order to determine their life satisfaction and to identify early predictors of vocational rehabilitation outcome. <u>Main results</u>: Gender independently, 70 % of the national sample were satisfied with life as a whole (were happy). The ten domains formed a 4-factor pattern: ”Closeness, Health, Spare time, Provision”. Seven domains were sizeable predictors of overall life satisfaction. In a complex manner socio-demographics were predictive of (gross levels) all LiSat-11 items. Main predictors were perceived health, immigrant status and educational level. Generally, the vocational rehabilitees had low LiSat-11 levels except for the closeness items. They had relatively poor background resources (low “sense of coherence“ level) for successful coping. Whereas a positive rehabilitation outcome was accompanied by increases in several LiSat-11 aspects, only satisfaction with the vocational situation was clearly responsive. Three early predictors of outcome were identified: belief in vocational return, educational level and sense of coherence. <u>In summary</u>: Besides providing reference values for the LiSat-11 instrument, this dissertation demonstrates that different socio-demographic factors influence different areas of concern (domains) in 18- to 64-year-old Swedes. In turn, satisfaction derived from different areas heavily influences level of overall life satisfaction. Moreover, the vocational rehabilitees generally seemed to be predisposed to being poor copers, possibly a major background of low levels of many LiSat-11 aspects. The identified set of predictors of the outcome of vocational rehabilitation emphasizes a need for focusing on psycho-social aspects within vocational rehabilitation.