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<p>Pyrogens are substances that may induce fever in the human body. They can be parts of bacteria, virus or fungi and due to the reaction they may cause in the body, they are routinely looked for in the medical technology industries. A method called <em>in vitro</em> pyrogen test (IPT) has been developed to detect these pyrogens. It is based on the fever reaction in the human body and only requires blood in combination with a solution believed to contain pyrogens. If the result is positive, the production of cytokines is started. The cytokines of interest in the IPT method are those involved in the fever process and two of them are IL-1<em>β</em> and TNF-<em>α</em>, which are the cytokines used as markers of infection in this study. Since the production of cytokines is in proportion to the amount of pyrogens, the inflammation-inducing potential of the sample can be decided. Due to problems in standardizing the method, mainly because it handles with living blood cells, focus is still pointed at improving it. The aim of this study was to optimize parameters within the IPT method by analysing air samples taken in indoor surroundings believed to contain pyrogens. The different parameters included extraction of the filter from the air sampling, incubation of whole blood and sample extract and analysis of the incubation with ELISA (enzyme linked immunosorbent assay). More specific, some of the issues concerned extraction media, time and shaking intensity for the extraction, blood ratio for the whole blood incubation and cytokines suitable for the method.</p><p>A possible approach for the IPT method, when analysing air samples containing pyrogens, was reached.</p> / <p>Pyrogener kallas ämnen som framkallar feber och de kan exempelvis bestå av hela eller delar av bakterier, virus eller svamp (fungi). En metod som kallas för in vitro pyrogen test (IPT) har utvecklats för att detektera dessa pyrogener. Metoden bygger på att en lösning som misstänks innehålla pyrogener får komma i kontakt med blod från en människa. Efter en inkubering på mellan 4-24 timmar har blodet reagerat på eventuella pyrogener och bildat cytokiner, där mängden cytokiner är proportionell mot mängden pyrogener. De intressanta cytokinerna i den här studien var IL-1<em>β</em> och TNF-<em>α</em>, som båda är involverade i feberprocessen. Det har varit svårigheter med att standardisera metoden, mycket beroende på att det är levande celler som hela metoden bygger på, så syftet med den här studien var att förbättra in vitro pyrogen test. Luftprover tagna i inomhusmiljöer som misstänks innehålla pyrogener har använts i försöken att optimera varje steg i processen. De olika stegen inkluderade extraktion av filter som använts vid luftprovtagningen, inkubering med helblod och provextrakt och analys av inkuberingen med ELISA (enzyme linked immunosorbent assay). Några av de parametrar som undersöktes gällde extraktionsmedium, skaktid och skakintensitet under extraktionen, blodförhållande under helblodsinkuberingen och lämpliga cytokiner för metoden.</p><p>Studien resulterade i att en metodik, för att analysera luftprov innehållande pyrogener med<em> in vitro</em> pyrogen test, kunde tas fram.</p>

published_or_final_version / Medicine / Master / Master of Medical Sciences

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / abstract / toc / Physiology / Master / Master of Philosophy

published_or_final_version / Pharmacology / Master / Master of Philosophy

published_or_final_version / Physiology / Master / Master of Philosophy

Endotoxins or lipopolysaccharides (LPS), highly toxic component of the outer membrane of gram-negative bacteria, are normally present in the mammalian gut lumen.In this thesis, I investigated, in laboratory animals, whether these gut-derived endotoxins play a role in pathophysiology resulting from intestinal dysfunctions caused by intestinal ischaemia and heat-stress.In primates, reperfusion of the splanchnic region after a temporary ischaemia was followed by a rapid increase in LPS concentration, first in the hepatic portal plasma and, ten minutes later, in the systemic arterial plasma. Rises in plasma LPS concentrations during or following the temporary intestinal ischaemia was prevented by prophylactic administrations of corticosteroids, anti-LPS IgG antibodies and oral, non-absorpable, antibiotics agents which appear to stabilize cellular membranes, aid the reticuloendothelial system in removal of LPS from the circulation and destroy the intestinal aerobic gramnegative bacteria respectively. In addition, administration of therapeutic anti-LPS antibodies also rapidly reduced the plasma LPS concentrations to baseline during an endotoxaemia. In a control heat-stress model, elevations in plasma LPS concentration commenced at rectal temperatures greater than 41,SoC. Like the intestinal ischaemia model, this occurred first in the hepatic portal plasma, and 10-15 minutes later, in the systemic arterial plasma. Peak plasma LPS levels of about 0,3 ng/ml, measured in heat-stressed primates, have proved in previous studies, to be toxic. A rapid decline in mean arterial pressure was followed by increases in plasma LPS concentrations and heart rates. Reductions in splanchnic blood flow and consequent local ischaemia coupled with thermal injury to the intestinal wall and the liver, may have permitted rises in plasma LPS concentration. Furthermore, as in the ischaemia model, prophylactic administrations of corticosteroids, anti-LPS IgG antibodies, and oral, nonabsorbable antibiotics prevented a rise in plasma LPS concentration. Of importance, prophylaxis with intravenous corticosteroids and 'anti-LPS IgG antibodies increased the survival rates significantly in heat stroke in primates. In addition, monkeys having high titres of "natural" antiLPS IgG antibodies had lower plasma LPS concentrations and survived the induced-heat stroke. It is suggested that other pathophysiologic conditions which compromise the integrity of the gut wall would also lead to the development of an endotoxaemia, and that gutderived endotoxins contribute to the athogenesis of heat stroke and treatments with corticosteroids and anti-LPS IgG antibodies may prove beneficial in other endotoxinrelated disorders. / Thesis (Ph.D.)-University of Natal, Durban, 1988.

The vagina is one organ of the body which has not been studied exhaustively. Moreover, most of the studies found in the contemporary literature have been performed on women affected by a variety of genital diseases. In the present study the vaginal epithelium was examined with a histological method, morphometry, whereby cyclical changes related to hormonal variation during the menstrual cycle were demonstrated. Determination of the quantity of estrogen receptors in the vaginal epithelium on two occasions during the menstrual cycle revealed a significantly greater number in the follicular than in the luteal phase. The results of these studies indicate the presence of a menstrual variation in the vaginal epithelium comparable to that in the endometrium. Phenoxymethylpenicillin (pcV) was used as a marker substance to study the dynamics of the transport mechanisms into the vagina. PcV was found to accumulate in the vaginal fluid and high concentrations persisted for a long period of time. In hysterectomized women, the appearance of pcV in the vaginal fluid followed the same pattern. Consequently, the substance is transported through the vaginal wall and need not enter with the secretions from the internal genitalia. The greatest concentration of pcV was in the distal portion of the vagina, possibly due to the specific internal circulation of fluid within the vagina. Bacterial vaginosis as an example of an ‘ecological disease’ has been studied with regard to the formation of endotoxin, a constituent of the cell wall of Gram- negative bacteria. Large amounts of endotoxin were found and the clinical implication of this finding has been pointed out. Furthermore, the influence of pcV on the vaginal microbial flora of healthy women has been investigated. A change from a situation with predominance of lactobacilli to the appearance of Gram-negative rods was observed. In one of the women the lactobacilli disappeared completely and were replaced by E. coliand high levels of endotoxin in the vaginal fluid were found. This study demonstrates the complexity of the ecological balance of the vaginal microbial flora and illustrates the difficulty of defining a ‘normal’ vaginal condition. Is there any unquestionable state of ‘normality’ even in a healthy woman free from symptoms of genital disease? / <p>S. 1-22: sammanfattning, s. 25-64: 6 uppsatser</p> / digitalisering@umu

This study was conducted to improve knowledge of the impact of chronic soil water deficit and to test a novel technique of water management consisting of Lipo-chitooligosaccharides (LCO) spray application. It also aimed at evaluating changes in canopy reflectance due to water stress and LCO spray. Water stress during reproductive development resulted in an important decrease of plant physiological activity, vegetative growth, and productivity, and accelerated plant senescence at both water stress levels. Water deficit increased leaf reflectance in the visible and decreased it in the infrared ranges of the spectrum at both imposed stress levels. Foliar application of LCO affected overall plant physiological activity, increased flower and pod numbers. LCO treatment had the largest positive effect on the growth pattern of soybean at the medium stress level, which is the stress level most commonly observed in standard farm-field conditions. LCO treatment constitutes a potential technology for reducing water deficit effects. (Abstract shortened by UMI.)