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14C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used 14C-breath tests: 14C-triolein (exam

This study focuses on various aspects of costs of reproduction and the evolution of energetic breeding tactics. It emphasizes the distinction between demographic costs of reproduction expressed already before current offspring have reached independence (prebreeding costs), and costs expressed only after offspring independence (postbreeding costs). Prebreeding costs have only rarely been appreciate

The human neutrophil is the most abundant granulocyte and the major type of cell involved in an acute inflammatory response. Neutrophils are armed with various systems of enzymes, that can find and kill pathogens, but unfortunately, these "weapons" cannot distinguish between the host tissues and the "invaders." Therefore, an extensive neutrophil reaction leads to continuous release of toxic metabo

Phosphoinositides (PIs) play major roles in cell signal transduction. Although it is clear that PIs are important components also in plant signalling, little is known about their roles in plant cells, compared to animal cells. This thesis describes work on two PI-dependent enzymes involved in plant intracellular signalling, phosphoinositide-specific phospholipase C (PI-PLC) and 3-phosphoinositide

Fibromyalgia syndrome (FMS) is characterised by diffuse, long-lasting, widespread pain and aching, accompanied by fatigue, stiffness and sleep disturbances. The symptoms may be aggravated by physiological and psychological overload. The aim of this thesis was to obtain further knowledge of the functional limitations and disabilities of patients with FMS and to evaluate the effects of physical exer

Alveolar fluid clearance is driven by active absorption of Na+ across the alveolar epithelium. Development and hormonal regulation of alveolar fluid clearance over 1 hour was studied by instillation of a protein-containing, isosmolar fluid into lungs of fetal, newborn, and adult guinea pigs. After 1 hour, a sample of remaining alveolar fluid was collected and the change in protein concentration wa

The overall aims of this work were to evaluate a method of assessing postural control, measured by balance in single-limb stance on a force platform, and to study balance in single-limb stance in individuals with non-operated anterior cruciate ligament (ACL) injury in comparison with that of uninjured controls. Ninety-nine patients (99) with ACL injury and 141 uninjured subjects were included in

This thesis concerns alterations in signal transduction in Schwann cells as a response to nerve injury as well as their survival, proliferation and death. Enzymes and transcription factors belonging to the mitogen activated protein kinase (MAPK) and the stress activated protein kinase (SAPK) pathways were studied. This included the extracellular-signal-regulated kinase 1/2 (ERK1/2), c-Jun N-termin

This thesis documents my work in the luminosity and supersymmetry groups of the ATLAS experiment at the Large Hadron Collider. The theory of supersymmetry and the concept of luminosity are introduced. The ATLAS experiment is described with special focus on a luminosity monitor called LUCID. A data-driven luminosity calibration method is presented and evaluated using the LUCID detector. This method

The aim of this dissertation was to examine whether the temporal distance of moral events affects the moral judgments and decisions people make in response to those events. Drawing upon Construal Level Theory (CLT; Trope & Liberman, 2003) which posits that the distant future is represented at a higher, more abstract level of mental construal than the near future, and that high-level mental con

The design and implementation of a hearing conservation programme in a heavy industry with high noise levels is described. Action was taken on several points, including noise measurements, noise reduction, education on hearing protector use, and audiometric monitoring. It was found that the noise at the plant has been greatly reduced during a period of 25 years. The reduction in noise was made pos

Cardiovascular diseases are characterized by changes in morphology and function of the blood vessels. Different signalling molecules are involved in these changes. Endothelin-1 (ET-1) is one of the most potent signalling molecules found in man. Its actions are mediated by two receptors, the ETA and the ETB receptors. The ETA receptor is located on the smooth muscle cells and mediates potent contra

Non-heme mononuclear iron oxygenases catalyze a large number of oxidation reactions in biological systems. The reactions are often proposed to proceed via the intermediacy of high valent Fe(IV) oxo (ferryl) or, Fe(V) oxo (perferryl) intermediates. Therefore, in order to mimic the high valent Fe(IV) oxo chemistry as well as the catalytic processes exhibited by those enzymes, new functional model co

The diagnostic value of modern fast pulse sequences and breath-hold technique was evaluated in a prospective study of patients with suspected biliary diseases. The cost-effectiveness of MRI compared to ultrasound was calculated. Characteristics of acute cholecystitis and cholangitis were evaluated, the appearance of bile in MRCP with reference to its chemical and physical properties was studied, a

Aggregation in protein-surfactant systems have been studied with the ambition of reaching a deeper understanding of the balance of the interaction forces involved. A pure system with maximized electrostatic interactions has been used. The approach has been to use a step-wise sample preparation where initially a stoichiometric protein-surfactant salt is precipitated and freeze-dried. Secondly, the

Hematopoietic stem cells (HSCs) are responsible for the daily and life long production of large numbers of mature blood cells through highly regulated self-renewal and multilineage capabilities. Leukemias on the other hand, are characterized by a clonal, dysregulated, lineage skewed proliferation and impaired differentiation as the result of multiple accumulated genetic events. In acute myeloid le

It has been more than 50 years since the enzyme system ribonucleotide reductase (RNR), catalysing the reduction of ribonucleotides to deoxyribonucleotides, was first discovered. RNR was also the first time that radical chemistry was revealed in an enzyme. RNRs carry out a key step in the de novo synthesis of building blocks for DNA and have been found in almost all known organisms. Within this th

The use of genetically modifi ed neural stem and progenitor cells could possibly be a future strategy for repairing a brain suffering from neurodegeneration. However, so far it has proven diffi cult to maintain sufficient levels of a transferred gene in suitable cell types, after transplantation. In the present thesis I studied the silencing of transgenes induced upon differentiation of neural pro

Extracellular nucleotides induce dilatation and constriction of blood vessels by activation of P2 receptors. In this thesis the vasomotor effects of P2 receptor activation were studied in the rat mesenteric artery, and their changes in congestive heart failure (CHF) were evaluated using in vitro pharmacology, electrophysiology and competitive RT-PCR. Vasodilatation was induced by activation of P2Y

One of the major challenges facing the world today is the reduction of our dependency on fossil resources as their exploitation has severe negative effects on the environment. One way of realizing this is to utilise the components of lignocellulosic biomass to a greater extent as feedstock for various industrial products. However, such utilisation requires the extraction of the biopolymers from th