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Neuroblastoma Cell Differentiation: The Role of Neurotrophin Receptor Signaling and N-myc Expression

Neuroblastoma is a tumor of sympathetic nervous system derivation, mostly afflicting young children. This thesis is focused on a group of receptor proteins for neurotrophic factors, the Trk family, and on N-Myc, a transcription factor, all important in the formation of the sympathetic nervous system as well as in determining neuroblastoma patient outcome. Expression of trkA and trkC is linked to f

Protein Microarrays Based on Single Framework Recombinant Antibody Fragments (SINFABS) - Catcher and Carrier - A Crucial Combination

Antibody-based microarrays are among the novel class of rapidly evolving proteomic technologies. In recent years, antibody microarrays have emerged as a unique tool for high-throughput protein expression profiling with great promise within biomedicine and a wide range of potential applications, including disease diagnostics and biomarker discovery. In order to evolve the technology from small dedi

From Sequence to Structure- Characterizing Human and Plant Aquaporins

Aquaporins constitute a class of membrane proteins that create pores through the lipid bilayer of biological membranes, facilitating the passage of water and other small solutes. Nearly all living organisms possess a more or less intricate set up of aquaporin proteins and the importance of these channels has been implicated in many aspects of health and disease. The aim of the projects summarized

Functional studies of Wilms’ tumor gene 1 (WT1) in hematopoiesis and leukemia

Wilms’ tumor gene 1 (WT1) is a zinc-finger transcription factor that is involved in the development of urogenital organs and mesothelial tissues. It was initially identified as a tumor suppressor gene, based on the observation that somatic inactivation of the gene predispose for development of the pediatric kidney cancer Wilms’ tumor. A role for WT1 in hematopoiesis was suggested based on the fact

Renormalization in Effective Field Theory and Hidden Radiation

This thesis dealswith the field of high-energy particle physics. It ismainly concernedwith two issues: the “renormalization of effective field theories” and the “detection of hidden sectors”. The first two papers are dedicated to the renormalization issue while the second two deal with the hidden sectors. Renormalization is crucial when one calculates physical observables to a high degree of preci

Retinal Transplants: Growth Differentiation Integration Organization and Survival

The goal of the study was to get a better understanding of factors controlling the growth, differen-tia-tion, integration, organization and survival of retinal transplants, with the long-term view of eventually developing retinal transplantation into a clinically useful procedure for treating degenerative retinal disorders such as retinitis pigmentosa. Embryonic day 15 rabbit retinas were transpl

ß2 integrin-induced signal transduction events in human neutrophils

Inflammation is a localized protective response in vascularized tissues and can be induced by microbial infection or cell and tissue injury. Polymorphonuclear neutrophils (PMN) are the most common white blood cells and are recognized as major cellular mediators of acute inflammation. PMN are highly mobile cells that possess regulated mechanisms for controlling the expression and activation of adhe

Improving Parton Showers with Fixed Order Matrix Elements

This thesis considers numerical simulations of high energy particle collisions, and improvements in the description of multiple collimated jets of hadrons in collision events in particular. In the event simulation software called event generators, the structure of multi-jet events is determined through an interplay of the input calculation, parton showers and phenomenological hadronisation models.

On lumbar spine stabilization

71 consecutive posterolateral lumbar fusions without decompression or internal fixation were evaluated with a mean follow-up time of 3.5 (2-7) years. The diagnoses were spondylolysis-olisthesis in 43 cases, degenerative disc disease and/or facet joint arthrosis in 16 cases and pain post laminectomy/ decompression in 12 cases. 54/70 patients had a solid fusion. In the group with spondylolysis-olist

Synergistic interactions involving amphiphilic polymers in solution

The properties of hydrophobically modified cellulose derivatives in aqueous mixtures with various other molecules have been investigated. Mixtures of a hydrophobically modified polymer and alkali-sensitive, degradable surfactants gave rise to time-dependent viscosities. With time, the viscosity decreased continuously or went through a maximum, depending on the initial surfactant concentration. Th

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

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

Vasodilator actions of EDHF and anandamide

Vasodilator responses to endothelium-derived hyperpolarizing factor (EDHF) and anandamide in isolated arteries were investigated. A combination of the potassium channel blockers charybdotoxin and apamin inhibits EDHF-mediated relaxations. Experiments in which charybdotoxin or apamin was substituted with other potassium channel inhibitors indicated that small- and intermediate-conductance calcium-a

Respiratory Sinus Arrhythmia and Emotion : Effects of pictorial stimuli and state anxiety

Respiratory sinus arrhythmia (RSA) refers to heart rate variations due to respiration, which results from parasympathetic nervous system activity mediated via the tenth cranial nerve, the vagus. Thus, the magnitude of RSA is considered as an index of cardiac vagal tone. This thesis explored RSA during emotional responding in healthy women and men. In the first two studies fear-relevant pictorial s

The telomere binding proteins in yeast and their role in telomere maintenance

Telomeres are the end-structures of linear chromosome which are crucial for maintaining genome integrity. The telomeres prevent the DNA-repair machinery from recognizing the chromosome ends as double-strand breaks and from end-to-end fusions. The telomeres are composed by short repetitive units of TG-rich DNA and associated specialized telomere-binding proteins. Due to that replication only can

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

Artifacts and Supraphysical Worlds : A Conceptual Analysis of Religion

It is a contested question in contemporary theories of religion whether the concept of religion can be defined in a sound way or not. Many theorists maintain that a universal but delimiting definition is impossible. In this study, by contrast, it is argued that a conceptual analysis of religion that holds universally is perfectly possible because the following thesis can be seen as a necessary and

Spontaneous Movements during Sleep Guide Spinal Self-organization: Formation and Expression of a Memory Trace

During development, information about the three-dimensional shape and mechanical properties of the body is laid down in the synaptic connectivity of sensorimotor systems through adaptive mechanisms. In spinal reflex systems, this enables the fast transformation of complex sensory information into adequate correction of movements. In this thesis, it is shown, in a computer simulation, that an unsup