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Effects of Total Parenteral Nutrition on the Exocrine and Endocrine Pancreas. An Experimental Study

During total parenteral nutrition (TPN) adequate nutrition is provided intravenously and the enteral route is bypassed. The integrity of the gastrointestinal (GI) tract, however, is dependent on the passage of food through it. This thesis deals with the effects of TPN on the pancreas and the parotid glands. TPN induced hypotrophy of the exocrine pancreas and the parotid glands. The amylase concent

How can p53 induce differentiation of leukemic cells?

The terminal differentiation of leukemic cells is closely connected to their death. The concept of differentiation therapy originates from the idea that forced maturation of leukemic cells could induce cell death without the side-effects that are provoked by ordinary chemotherapy. The tumour suppressor protein p53 is a transcription factor, and can induce cell cycle arrest and apoptosis of maligna

Reduced ROS production triggers arthritis / The role of T cells in arthritis pathogenesis

The aim of this thesis is to defend a novel mechanism that triggers arthritis susceptibility in both rats and mice through reduced production of reactive oxygen species (ROS), but also to introduce a novel model for chronic relapsing arthritis. Five papers are included, all of which employ animal models for rheumatoid arthritis and one that also uses animal models for multiple sclerosis. Paper I a

Electron Transport in Nanowire Quantum Devices

This thesis focuses on electron transport in semiconductor InAs/InP and InSb nanowire quantum devices. However, first the temperature dependence of classical charge transport in InSb nanowire field-effect transistors, FETs, is characterized, using InAs nanowire FETs as a reference. We find that the InSb FETs, in the same way as InAs FETs, are n-type with good current saturation and low voltage ope

S100B and Cardiac Surgery

The brain-derived protein S100B is a 21 Kda dimerand have been used as a serum marker for brain damage of different etiology. The feasability of protein S100B as serum marker for brain damage after cardiac surgery was studied in this thesis. One unexpected finding was made, which changed the basis for interpration of S100B levels. Shed blood collected during surgery with cardiotomy suction contain

Realism in metacognitive judgments : Effects of social factors

Theoretical accounts and models of calibration typically explain the degree of realism (validity) in confidence and frequency judgments in terms of different cognitive and methodological factors. The present thesis demonstrates that also social factors are of importance for the degree of realism in these types of metacognitive judgments. The results of Study I showed improved realism in pairs’ con

On the regulation and effects of chronic inflammation in inflammatory bowel disease

Inflammatory bowel disease is thought to result from the inappropriate and ongoing activation of the mucosal immune system driven by the presence of normal luminal flora. In this process monocytes/macrophages contribute to and maintain chronic inflammation by being both regulatory and effector cells. This study aimed at exploring the effects and regulation of chronic inflammation in inflammatory

Human fetal cerebral circulation - Perinatal Doppler velocimetry and fetal pulse oximetry studies

The studies upon which this thesis is based were designed to evaluate normal fetal and neonatal adaptation and the effects of obstetrical interventions during labor and delivery on fetal and neonatal cerebral circulation. Non-invasive Doppler ultrasound was used to record blood flow velocities from the middle cerebral artery (MCA) both antenatally from the fetus, and from the newborn in the early

Sparse Modeling Heuristics for Parameter Estimation - Applications in Statistical Signal Processing

This thesis examines sparse statistical modeling on a range of applications in audio modeling, audio localizations, DNA sequencing, and spectroscopy. In the examined cases, the resulting estimation problems are computationally cumbersome, both as one often suffers from a lack of model order knowledge for this form of problems, but also due to the high dimensionality of the parameter spaces, which

The Formation of Giant Planets

Giant planets form embedded in a protoplanetary disc around a young star. Close to the midplane a large fraction of the available mass in solids is found in particles of cm to dm in size, which drift towards the star due to friction with the surrounding gas. In paper I, II, III we describe a novel theory that explains how embryos, planetesimals larger than ~1000 km, grow efficiently by sweeping up

Mechanisms of survival and maintenance of Hematopoietic Stem Cells and Multipotent Progenitor Cells

Hematopoietic stem cells and progenitor cells are maintained in the bone marrow microenvironment, where factors including soluble and membrane-bound cytokines influence the processes of self-renewal, proliferation and differentiation. Two nonreduntant cytokines with effects on hematopoiesis, Kit Ligand (KL) and Flt3 Ligand (FL), signal via related tyrosine kinase receptors, c-kit and Flt3. In this

Effects of dietary fibre on the human metabolism and metabolome

It is well-known that dietary fibre can have a positive effect on the development of lifestyle-dependent diseases such as cardiovascular disease and type 2 diabetes. However, the effect may be different for different kinds of fibre and different sub-populations at risk. Therefore, the effects of three different kinds of fibre on postprandial and long-term response in healthy subjects were investig

Perception of touch : Developmental and personality factors in touch avoidance

The studies in this doctoral thesis investigated the concept of touch avoidance. Touch avoidance indicates a person’s negative affect toward physical contact/touch. In study 1 the aim was to develop a questionnaire that measures the level of touch avoidance. The results showed that touch avoidance can be measured along five different dimensions. The results are discussed in relation to attachment

Nitric Oxide Synthase in Pancreatic Islets During Trauma and Parenteral Feeding

The influence of trauma (acute pancreatitis) or total parenteral nutrition (TPN) on pancreatic islet hormone secretion in relation to islet expression of inducible nitric oxide synthase (iNOS) was investigated. Acute pancreatitis resulted in an impaired glucose-stimulated insulin secretion (GSIS) which was found to be parallelled by a marked expression of iNOS and an exaggerated NO production in t

Processing of TNF-receptors to soluble receptor forms in myeloid cells

TNF (Tumor Necrosis Factor) is a pro-inflammatory cytokine which binds to two cell surface receptors, TNF-R55 and TNF-R75. The receptors undergo proteolytic cleavage and release a fragment (soluble TNF-receptors or TNF-Binding Protein), TNF-R55-BP and TNF-R75-BP. Soluble TNF-receptors are able to bind and inactivate TNF. The release of soluble TNF-receptors was measured with ELISA. TNF binding cap

Renal dysfunction in orthopaedic surgery - with special reference to drug effects in the elderly

Total hip replacement (THR) is a common procedure, generally performed in elderly persons. Previous studies indicated that the use of isoxazolyl penicillins could induce a transient post-operative renal dysfunction in these patients. By measuring urinary levels of markers for glomerular (albumin, IgG) and tubular (protein HC) function we studied the influence of systemic cloxacillin, the gentamic

Systemic and Local Inflammatory Mediator Response to Major Surgery

Cell-signalling via cytokines modulates the local response to surgical trauma, directs the immunologic response and initiates the healing process. Surgical trauma induces a systemic cytokine response and a down-regulation of the antigen presentation capacity of monocytes (HLA-DR expression), which is associated with a poor prognosis if pronounced. The aims with the studies in this thesis were to i

A Study of Biomass Combustion Problems and the Selective Catalytic Oxidation of Ammonia

Increasing awareness of the need of reducing CO2, NOx and SOx emissions from combustion systems has led to a strong interest in biomass as a fuel source. Using it in combination with fluidised bed combustion technology can lead to a lowering of NOx emissions to the atmosphere. However, this is not a problem-free technique, since the flue gas can contain ammonia, NOx and tar. The fluidised bed can

The Oxygen Evolving cycle in Photosystem II studied with EPR Spectroscopy at different pH and Temperature

PSII catalyses the light-induced water splitting process which leads to electron transfer through the thylakoid membrane and formation of energy rich molecules. Several redox components including a Mn4Ca, an amino acid residueYZ, two special Chl molecules P680, two Pheo and two quinone molecules participate in this process. Another component of PSII which interacts magnetically with Mn4Ca is D2-Ty