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Persistent organic pollutants (POPs) pose serious threats to our global environment. These compounds have high chemical and biological stability and they are also very lipophilic. These characteristics not only render POPs the ability to spread widely and pollute remote areas, they also make them prone to accumulate in adipose tissues of living organisms. Consequently, it is important to monitor P
The immune response is designed to protect the body from harmful microbial invasions. However, when the immune system attacks itself instead, an autoimmune reaction starts that damage our own cells, tissues and organs. Despite decades of research concerning the etiology of autoimmune diseases the molecular mechanisms of these disorders are poorly understood as they are complex and influenced by bo
The purpose of this study was to investigate the suggestions that macrophages, and the systems generating nitric oxide (NO) and carbon monoxide (CO), i.e. nitric oxide synthases (NOS) and heme oxygenases (HO), could be important for peripheral nerve regeneration. Immunocytochemistry was used to visualise invading and resident macrophages, inducible NOS (iNOS), two isoforms of HO (HO-1 and HO-2),
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
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
Replacing fossil fuels by biofuels such as ethanol is considered a promising alternative to reduce greenhouse gas (GHG) emissions and mitigate climate change. Biofuels produced from lignocellulosic biomass, so-called second generation biofuels, result in decreased GHG emissions and limit competition with food and animal feed production. Interest in producing ethanol from lignocellulosic biomass ha
Population dynamics in space and time are manifested as changes in the distribution and abundance of organisms. To couple such patterns to the underlying processes is a central question in ecology and also key to successful management. In this thesis, I use theoretical models as well as time series data to analyze population dynamics in environments that are variable in space or time. An example o
In this thesis I have investigated the effects of pesticide exposure on the ecosystem level using various types of experimental ecosystems, i.e. microcosms. The direct effect of exposure to cyperemthrin, a pyretroid insecticide, was a rapid decrease of crustancean zooplankton in enclosures in a lake. In the exposed enclosures the biomass of algae, heterotrophic nanoflagellates, ciliates and bacter
Different aspects of porphyrin proteins have been studied with theoretical methods. For example, we have studied: - The importance of hydrogen bonds for the discrimination between carbon monoxide and molecular oxygen by myoglobin, the oxygen carrier in muscles, modelling the active site both in vacuum and in the protein matrix - The inner-sphere reorganisation energy during electron transfer for
Ferrochelatase catalyses the synthesis of heme by inserting Fe(II) into protoporphyrin IX. The structure of ferrochelatase from yeast has been determined (2.4 Å). The structure is homodimeric with each of the monomer made up of two Rossmann type domains with an active-site cleft between them. Metal binding studies with Co(II) and Cd(II) ions reveal the metal binding residues as being the His-Glu
An increase in the plasma level of creatine kinase MB (CKMB) has long been used to indicate acute myocardial infarction (AMI). For optimal treatment an early diagnosis is important. An increase in the ratio between the two isoforms of CKMB is seen much earlier than an increase in the total level of CKMB. One possible method for separating these isoforms could be weak affinity chromatography (WAC).
From 1990 to 1998, estimations of the effective dose from external as well as internal irradiation from 137Cs and 134Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of 137Cs was in the range 0.9-2.7 MBq m-2. Yearly
Acute liver failure is accompanied by a high rate of bacterial septic complications. High portal level of lipopolysaccharide (LPS) can lead to a pronounced secretion by Kupffer cells of pro-inflammatory mediators which have been shown to be early and important mediators of liver injury. Pathogenesis of inflammatory bowel disease (IBD) is complex; involving environmental, genetic, microbial, and im
In this project, the potential of magnetic resonance (MR) imaging and spectroscopy in studies of microcirculation and haemodynamics was evaluated. The spatial and temporal characteristics of human pulsatile brain-tissue movements in healthy individuals, relevant for the understanding of the cerebrospinal-fluid (CSF) circulation and the pathogenesis of hydrocephalus, were thoroughly investigated. A
Calreticulin (CRT) is an endoplasmic reticulum (ER)-located protein involved in quality control of newly synthesized proteins as well as in calcium homeostasis of the cell. Most of what is known about CRT arises from studies of mammalian systems. However, using a Arabidopsis thaliana CRT gene expressed in mouse fibroblasts deficient of endogenous CRT, the wild type phenotype could be rescued with
The polyamines, putrescine, spermidine, and spermine, are essential for all forms of life. The polyamine biosynthetic pathway has been shown to be a potential target for drugs against various trypanosomal parasitic diseases. The two main enzymes in the biosynthesis of polyamines are ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC). ODC catalyzes the first step of pol
Studies have found that depressive states in old age that do not fulfil the criteria for major depression are clinically important depressive states. These depressive states are common in primary care patients. Therefore, studies of late-life depression from a primary care perspective are needed. A depressive rating scale, Hopkins Symptom Checklist-25 (HSCL-25), was used in a community survey in 1
In this thesis, in situ doping during growth of III-V semiconductor nanowires, primarily for photovoltaic applications, is investigated. The nanowires were grown by metalorganic vapor phase epitaxy (MOVPE), with gold seed particles. After growth the nanowires were characterized using various techniques, including photoluminescence, transmission electron microscopy and electrical measurements of co
An essential part of the development of new radiopharmaceuticals for use in diagnostic nuclear medicine is the determination of its biokinetic properties. The uptake and turn-over of the radiopharmaceutical in the source organs is of great interest since this could determine whether the radiopharmaceutical would be suitable for clinical use or not. It is also important that the biokinetics and dos
Transient absorption laser spectroscopy and resonance Raman spectrscopy have been used to study conjugated polymers and oligomers. To extract more information the measurements have been compared to computer simulations and calculations. In order to obtain a better understanding of the role of conformational disorder in the photophysics of light-emitting, conjugated polymers the ultrafast transient
