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Antithrombotic Effects of Activated Protein C and Heparins in Deep Arterial Injury

The investigations presented in this thesis have evaluated different strategies to prevent thrombosis in an experimental model of deep arterial injury in rats. Unfractionated heparin (UFH) is often used to prevent thrombosis in microvascular surgery and in other vascular interventions, but a major drawback of UFH is increased bleeding. In the first paper the low-molecular-weight heparin (LMWH) da

Endothelial Barrier Dysfunction in Multiple Organ Injury. An Experimental Study in Rats

Multiple organ dysfunction syndrome (MODS) is still the leading cause of mortality in the surgical intensive care unit. The effect on among others endothelial barrier permeability, reticuloendothelial function, organ function and protease-antiprotease activities was studied following a variety of challenges, especially over-activation of macrophages induced by intraperitoneal administration of zym

Pollen Competition as a Target for Sexual Selection in Plants

According to the theory of sexual selection, traits can evolve because they confer a mating advantage in competition with members from the same sex. In animals, sexual selection is considered as an important evolutionary force. In this thesis I have investigated the potential for sexual selection in plants. I have concentrated on the phase of reproduction that occurs after pollinators have deposit

Electron Transport in Semiconductor Nanowires

In this thesis, semiconductor nanowires are studied from the point of view of growth and electrical properties. The growth of nanowires is done by chemical beam epitaxy (CBE), an ultra-high vacuum technique allowing a precise control of precursor deposition and low growth rates. In conventional epitaxy, growth is usually two or three- dimensional, depending on growth conditions and material combin

Studies of the pathogenesis of hemolytic uremic syndrome and thrombotic thrombocytopenic purpura

This study investigated the pathogenesis of hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP). (1) The relative roles of lipopolysaccharide and Shiga-like toxin-2 were studied in a mouse model of Escherichia coli O157:H7 infection. Both factors were found to be important for the virulence of the strain and contributed in an additive manner. The mouse model mimicked cert

Type 2 Diabetes in a Defined Population The Skaraborg Hypertension and Diabetes Project

To examine cardiovascular risk factors, glycaemic control and survival in patients with type 2 diabetes mellitus (T2DM) treated in primary care, patients with T2DM and a randomised age-stratified sample of men and women aged ≥40 years living in the same community were surveyed 1992-1994. ß–Cell function and insulin resistance were estimated using the Homeostasis Model Assessment (HOMA). Vital stat

Variational Methods in Combinatorial Optimization and Phylogeny Reconstruction

Algorithms based on the variational approach, as used in statistical physics, are developed. For constraint satisfaction problems a novel cost function, based on information-theoretic arguments, is introduced, and an algorithm similar to the mean-field annealing algorithm is proposed. It outperforms the conventional mean-field algorithm, and its performance is comparable to good problem-dedicated

Mechanisms of phagocytosis resistance in Streptococcus pyogenes

A distinguishing feature of Streptococcus pyogenes (GAS) is their ability to resist phagocytosis in whole human blood in the absence of type-specific antibodies, a property that is dependent on the expression of the surface associated M proteins. A common characteristic of M proteins is their interaction with a variety of host proteins including the complement regulatory protein factor H (FH) and

Acute postoperative and cancer-related pain management, Patients´ experiences and perceptions in relation to health-related quality of life and the multidimensionality of pain

This thesis describes patients in acute postoperative pain as well as patients with acute cancer-related pain in palliative care, and their experiences and perceptions of pain management in relation to HRQOL and the multidimensionality of pain. A combination of qualitative and quantitative methods was chosen. Data were collected using interviews and questionnaires; APS, SF:36 and a new developed q

Novel functions of cardiovascular P2 receptors

The aim of the thesis was to examine the expression and function of the extracellular nucleotide P2 receptors in the cardiovascular system. In the cardiovascular system nucleotides are released during shear stress, hypoxia, ischemia, from endothelial cells, smooth muscle cells, aggregating platelets, inflammatory cells and erythrocytes. We demonstrate that ATP, ADP, UTP and UDP induce vascular rel

Regulation of the cytoskeleton and the adhesiveness of intestinal epithelial cells by leukotriene D4

Leukotrienes belong to a family of biologically active conjugated trienes that are formed from arachidonic acid via the 5-lipoxygenase pathway and are important mediators of inflammatory reactions. The CysLT1 receptor that specifically serves as receptor for leukotriene D4 (LTD4) has been identified as a G-protein coupled receptor. Cell-cell and cell-matrix complexes of epithelial cells are inter

Transvascular exchange and organ perfusion with reference to colloid and hypertonic solutions, and to endotoxaemia

Changes in vascular permeability can immensely change plasma volume and affect the degree of oedema in the body. In diseases with an increased vascular permeability, adequate fluid therapy is of considerable importance to prevent hypovolaemia. Mechanisms behind differences in effectiveness of various plasma volume expanders to restore a low plasma volume and a compromised microcirculation are stil

Neurogenesis and transplantation in stroke-damaged brain

Stroke in young adult rodents triggers neurogenesis in the damaged striatum and intact hippocampus. as stroke happens frequently in aged individuals it is of great importance to know whether aging affects brain recovery mechanisms. Aged and young adult rats were subjected to stroke by transient occlusion of the middle cerebral artery and proliferating cells were labeled by intraperitoneal administ

Molecular and functional studies of the BCR/ABL1 fusion gene

The BCR/ABL1 fusion gene is associated with chronic myeloid leukemia and a subgroup of acute lymphoblastic leukemia. The general aim of this thesis was to increase the understanding of BCR/ABL1-induced leukemogenesis by molecular and functional studies of this fusion gene. In Article I, an experimental U937 cell line model with inducible expression of BCR/ABL1 was established and characterized. Ex

On the induction and function of Foxp3+ regulatory T cells

This thesis is based on three original papers with the overall aim to study the mechanisms of induction and function of Foxp3+CD4+CD25+ regulatory T cells. Regulatory T cells induce down-modulation of costimulatory molecules CD80 and CD86 on dendritic cells in vitro. In the first study we further show that the extent of down-modulation is functionally significant since regulatory T cell condition

Characterization of human myeloid progenitors and their differentiation

All hematopoietic cells are derived from the hematopoietic stem cells (HSCs) in a continuous and dynamic process, regulated by a network of transcription factors in different combinations and extrinsic signals from growth factors (GFs) and other factors in the microenvironment. In the initial stages of hematopoiesis HSCs differentiate to progenitor cells with gradually more restricted lineage pote

The influence of abdominal surgery on energy expenditure and working capacity

The overall aim of this work was to study the influence of surgery on energy expenditure (EE) during working capacity measurements and during walking. In the first study the aim was to investigate whether two different devices were sensitive enough to reveal differences in energy expenditure during treadmill walking, and if the measurements were reproducible. It was shown that an airflow of 42.5

Crafting Democracy : Civil Society in Post-Transition Honduras

Civil society is frequently singled out as one of the most important factors in the democratization process, but existing research is often imprecise with regard to civil society’s relation to democratic development. This study analyzes how, and under what circumstances, civil society can contribute to democratic development in newly established democracies. A conceptual framework is outlined that

U-Pb geochronology of tectonothermal events related to the Rodinia and Gondwana supercontinents -observations from Antarctica and Baltica

This thesis presents data from two areas, Dronning Maud Land, Antarctica, and the Scandinavian Caledonides, Baltica. In addition, a comparative geochronological study is presented. The bedrock of Dronning Maud Land (DML) is dominated by migmatitic gneisses and post-tectonic intrusions. A migmatitic gneiss at Jutulsessen nunataks, Gjelsvikfjella, has a protolith age of 1163 ± 6 Ma and a migmatisati

Condition-Based Maintenance: Selection and Improvement of a Cost-Effective Vibration-Based Maintenance Policy for Rolling element Bearings

Modern machinery is expensive and therefore must run at high availability and effectiveness which cannot be achieved without an effective maintenance policy. Condition monitoring, (CM), techniques can be utilised to reduce or arrest the rate of deterioration of a component so increasing operating life. The main result reported in this thesis is that the rolling element bearing’s mean effective li