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Studies on the Physiological Effects of Microbial Exopolysaccharides

The spread of lifestyle-related diseases has become epidemic throughout the world. Impaired glucose metabolism and high levels of plasma cholesterol are risk factors for the development of type 2 diabetes and cardiovascular disease respectively. Soluble dietary fibers from plants, algae and mushrooms have been shown to positively regulate both glucose- and cholesterol metabolism indicating their v

Use of neural progenitor cell lines and astrocytes for transplantation and gene transfer to the CNS.

Intracerebral neuronal transplantation have been shown to ameliorate symptoms of brain dysfunction in both animals models and Parkinson's disease, although problems still remain. The newly introduced technique of ex vivo gene transfer could serve as an alternative approach, possible avoiding some of the draw-backs of the embryonal tissue used in neuronal grafting. We have investigated the feasibli

Proton-Conducting Sulfonated Aromatic Ionomers and Membranes by Chemical Modifications and Polycondensations

Proton-exchange membrane fuel cells (PEMFC)s are increasingly regarded as promising environmentally benign power sources. Intensive development is today directed towards reducing the cost and increasing the durability of the fuel cell, as well as expanding the operational window for the PEMFC for a range of applications. The proton-conducting membrane is one of the key components in the PEMFC. The

Modeling and simulation of electro-viscoelastic polymers

The electroactive polymer materials considered in this work react to electric stimuli by producing deformations. In some cases, the electrically induced deformations are moderate, while in other cases they can be very large and the specimen is stretched to more than twice its original length. The latter response is seen in so called dielectric elastomer actuators (DEA). The possibility of very lar

Development of Magnetomotive Ultrasound Imaging

The earlier abnormalities coupled with disease can be discovered in the body, the larger is the chance to survive the disease. Molecular imaging is a growing research field which aims to detect these abnormalities at a molecular level, when the chance of survival is still high. The main idea of molecular imaging is to use target specific contrast agents that accumulate at the diseased region at a

Chronic hepatitis C infection. With special reference to prevalence, aggravating factors and longterm outcome

Since the discovery of hepatitis C virus (HCV) in 1989, it has proved to be a formidable health problem with a major impact on morbidity and mortality throughout the world. In this investigation, patients with chronic hepatitis C infection have been studied with special reference to prevalence, aggravating factors and longterm outcome. The prevalence of HCV infection was high (approximately 10 %)

Hydrogen Production by Caldicellulosiruptor species: The Organism and the Metabolism

Hydrogen holds a great promise as an efficient and clean future energy carrier due to its high energy density and lack of pollutant generation. Anaerobic degradation of organic substrates by heterotrophic microorganisms enables the production of hydrogen from a wide spectrum of agricultural feedstock and waste products. Using thermophiles in this process is preferable for maximizing the substrate

Modeling of material behavior in metal forming

With an increasing demand to improve efficiency and to cut costs, the industry is constantly seeking to reduce the time and money spent in product development and manufacturing. Use of computer-based simulations has become more or less a standard tool to meet this demand. Cost reduction is in this way made possible by for example shortened product development cycles, less need for expensive protot

Dynamic Modelling of Emulsification in High-Pressure Homogenizers

Different approaches and sub-models for the modelling of emulsification in a high-pressure homogenizer are reviewed and compared in terms of both practical aspects and how well they describe what is currently known on the emulsification process in general and on high-pressure homogenization in particular. Special effort is devoted to comparing the model developments presented in the appended paper

Tectonic implications of ca. 1.45 Ga granitoid magmatism at the southwestern margin of the East European Craton

Between ca 1.53 and 1.40 Ga, the southwestern margin of the East European Craton was subjected to extensive magmatism and deformation. While various suites of anorthositic, mangeritic and charnockitic-granitic rocks were emplaced between ca. 1.53 and 1.50 Ga, a major event of A-type granitic magmatism took place around 1.45 Ga. During that event, numerous voluminous plutons were intruded in a wide

Interactions between streptococcal M proteins and human plasma proteins

Streptococcus pyogenes is a common human pathogen, which causes a variety of diseases. A major virulence factor of S. pyogenes is the surface-associated M protein, which mediates resistance to phagocytosis. Several studies indicate that M proteins inhibit complement deposition and thereby phagocytosis. It is often assumed that S. pyogenes lacking M protein activates complement via the alternative

Vascular receptor changes in ischemic stroke

The present thesis aimed to examine how ischemic stroke affects the vascular endothelin and angiotensin systems in cerebral arteries. To study vascular receptor changes in ischemic stroke transient focal ischemia was induced in rats. In addition, rat cerebral arteries and arterial smooth muscle cells were cultured for further analysis of cerebrovascular receptor regulation. For functional studies

Interstitial Laser Thermotherapy of Liver Tumours. Methodology and Application

Interstitial laser thermotherapy (ILT) is a method well suited for selective local destruction of malignant tumours. In the present work, a laser thermotherapy system based on feedback temperature control of energy delivery (through computerised feedback system) was developed. Temperature control was excellent in experiments without carbonization and with preserved light penetration, whereas tempe

Mechanisms behind the lipid-lowering effects of ACTH - Studies in different experimental models

Abstract Adrenocorticotrophic hormone (ACTH) has strong and direct lipid-lowering effects in man. All apoB-containing lipoproteins, i.e. VLDL, LDL, Lp(a), are reduced by 25-30%. In contrast, levels of HDL increase about 10%. In hepatic cell cultures, ACTH inhibits expression and secretion of apoB. In this thesis we corroborate that the reduced apoB synthesis, seen in hepatic cell systems, is als

Weichselian glaciations in the middle Notec River region, northwest Poland

This thesis presents results of studies on the ice flow pattern and ice movement mechanism during the Weichselian glaciations in the middle Notec River area, NW Poland. A new lithostratigraphy of the study area has been established, based on correlation of stratigraphical position, clast lithology, fabrics and grain size composition of till units. The lithostratigraphy covers two glacial advances

Recombinant CXCR4/CCR5 hybrid receptors as tools for studies of HIV-1 receptor usage

The chemokine receptors CCR5 and CXCR4 are required, together with CD4, for the entry of HIV-1 into target cells. CCR5 using HIV-1 dominates during transmission and the asymptomatic phase of infection. During progression, virus phenotypes with the ability to use CXCR4 emerge in about 50% of infected individuals. Individuals continuously harbouring CCR5-restricted isolates still progress to AIDS. D

The Operational Problem of Fire Control

The operational core of firefighting operations was examined. The effects of various firefighting procedures on the fire ground, their impact upon conditions on the fire ground in which decisions by commanding officers are made and the effects of allocating resources in time and space on the fire ground were explored. In addition, various approaches for modelling firefighting operations were discu

Midkine - a host defence protein

Every day we encounter many potentially harmful microbes in our environment. The epithelial linings constitute an anatomical barrier protecting us and they also produce antimicrobial polypeptides (AMPs) that act as a chemical barrier. These AMPs are small and positively charged, killing a broad range of microbes rapidly. They can either be constitutively produced or rapidly induced when epithelial

Pancreatic Cancer - Early Detection, Prognostic Factors, and Treatment

Background: Pancreatic cancer is the fourth leading cause of cancer-related death. Only about 6% of patients are alive 5 years after diagnosis. One reason for this low survival rate is that most patients are diagnosed at a late stage, when the tumor has spread to surrounding tissues or distant organs. Less than 20% of cases are diagnosed at an early stage that allows them to undergo potentially cu

Molecular Epidemiology of Breast Cancer

Hereditary breast cancer constitutes a considerable fraction of the total number of breast cancer cases occurring each year. Up until recently very few breast cancer predisposing genes were known, but many new common polymorphisms contributing to increased cancer susceptibility are continuously being identified. This thesis has focused on familial breast cancer and identifying as well as investi