Filetype
Streptococcus pyogenes causes infections only in humans, from trivial tonsillitis to life-threatening conditions. One of its most important virulence factors is the M-like protein family conferring resistance to phagocytosis to the bacterium. The M-like proteins are surface exposed rod-like molecules attached to the cell wall. Each strain of S. pyogenes expresses unique M-like proteins that bind t
In vertebrates the Major Histocompatibility Complex (MHC) plays a central role in the specific immune defence against various pathogens. Compared with other coding genes the MHC genes exhibit an extremely high level of polymorphism that is maintained by balancing selection. The importance in the immune defence and the polymorphism make these genes interesting to study from an ecological and evolut
The cytostatic drug 5-fluorouracil (5-FU) has been shown to affect both morphology and function of vascular endothelium. These effects could be part of the pathophysiology for 5-FU induced cardiotoxicity. The present thesis explores the mechanisms of this endothelial toxicity. In an animal model, treatment with thromboprophylactic doses of the low-molecular weight heparin (LMWH) dalteparin could
Increasing [K+]o is intimately coupled to progressive ischemia and reduced CBF. In isolated cerebral and mesenteric arteries, it was found that significant differences in the vascular responses to [K+]o exist. Among the species studied, human cerebral arteries were the most sensitive artery to increasing [K+]o. Rabbit basilar arteries, denuded from the endothelium, showed increased sensitivity to
Workers exposed to hand-held vibrating machines may risk developing a hand-arm vibration syndrome (HAVS), a condition which can cause chronic impairment and disability. The aims of this thesis were 1) to obtain deeper insight and further knowledge of HAVS and the consequences for hand function, and aspects of quality of life (QoL); 2) to investigate the usefulness of clinical assessments in diagno
In addition to proton-pumping complex I, the plant respiratory chain contains type II NAD(P)H dehydrogenases. These extra enzymes do not pump protons and consequently do not contribute to the electrochemical proton gradient. Database screening of the Arabidopsis genome identified seven type II NAD(P)H dehydrogenase homologues of which two and four genes were closely related to potato (Solanum tube
Lectins defined as non-enzyme, non-immunoglobulin carbohydrate binding proteins, have been found in a wide variety of viruses, bacteria, fungi, plants and animals. Although lectins have been purified from more than 60 different species of fungi, the structure and biological functions of these proteins are not well known. I examined the molecular structure of a lectin (designated AOL) isolated from
Type 2 Diabetes is a disorder that increases globally, but mainly in the western world. One of the hallmarks of Type 2 diabetes is insulin resistance in the target tissues of insulin action (adipose tissue, liver and skeletal muscle). In addition, most patients with Type 2 diabetes are obese. Increased release of free fatty acids from the enlarged and/or dysfunctional adipose tissue is suggested t
This work analyses several aspects of multi-conjugate adaptive optics (MCAO) for astronomy. The research ranges from fundamental and technical studies for present-day MCAO projects, to feasibility studies of high-order MCAO instruments for the extremely large telescopes (ELTs) of the future. The first part is an introductory exposition on atmospheric turbulence, adaptive optics (AO) and MCAO, esta
This thesis deals with the development and evaluation of some different optical techniques for tissue characterization. The main aim has been to improve and evaluate such investigative techniques in in vivo studies. In this attempt a key issue has been to gain understanding in the underlying mechanisms of laser-based diagnostics of premalignant and malignant lesions and to evaluate methods
Pathogenic bacteria express a wide array of surface proteins that interact with the environment. Many of these proteins are believed to be important for the virulence. This thesis deals with the binding of immunoglobulins (Ig) and complement regulating proteins to certain bacterial surface proteins. Protein L from Peptostreptococcus magnus binds to Igk-light chains while protein A from Staphylococ
The purpose of the study was to develop an ultrasound (US) protocol for evaluating congenital clubfoot pathoanatomy before and during early treatment. By using 3 easily defined and reproducible US projections the talonavicular and the calcaneocuboid joints were assessed. Normal configurations of the relationships at these joints were obtained by investigating 54 healthy babies at the ages of 0, 4
People can become sensitive to the general structure of different parts of the environment, often without studying that general structure directly, but through being incidentally exposed to instances that conform to the structure. When such learning proceeds unintentionally and gives rise to knowledge that is difficult to verbalize it is often referred to as implicit learning. One of the most comm
Migration of leukocytes from the circulating blood into the extravascular tissue is a key component in inflammatory reactions. Leukocyte extravasation (rolling-activation-adhesion-transmigration) is strictly coordinated by adhesion molecules and chemokines expressed on cell surfaces and in tissues. Tumor necrosis factor-alpha (TNF-alpha) is pleiotrophic cytokine, which plays an important role in t
General characteristics and outcome was evaluated in 177 consecutive patients who underwent a major amputation in a defined population. Smoking and diabetes lowered the mean amputation age. Healing failure at six months was seen in 24% of transtibial and in 11% of transfemoral amputees. Preoperative absence of gangrene and hemoglobin >120 g/L increased the risk of healing failure. Six months after
Aims of the study The aims of this study using Gadodiamide injection were to investigate: · Whether Gadodiamide injection was comparable to Gd-DTPA for the enhancement of CNS lesions. · The contrast effect at different field strengths. · The effective time-window for the enhancement of blood-brain barrier damage. · The relations between the concentration of contrast agent and enhancement in p
The aim of the present thesis was to enhance our understanding of social support for physical activity among adolescents. Earlier findings show inconsistent results with regard to the importance of social support. The present thesis includes three empirical studies examining adolescents (16-18 years) during their years in high-school. Study I was a cross-sectional quantitative study that concluded
This dissertation investigates the possibilities and limitations of time-dependent many-body perturbation theory by studying small Hubbard clusters for which the exact solution is available. The first part of the thesis is comprised of a short introduction to the concepts and methodologies used. The second part consists of an review of the main findings of the thesis and a short summary of four
