65 resultados para 0 (Inflammation Mediators)

em Helda - Digital Repository of University of Helsinki


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Cardiovascular diseases, which presently are considered inflammatory diseases, affect millions of people worldwide. Chronic infections may contribute to the systemic inflammation suggested to increase the risk for cardiovascular diseases. Such chronic infections are periodontitis and Chlamydia pneumoniae infection. They are highly prevalent as approximately 10% of adult population and 30% of people over 50 years old are affected by severe periodontitis and 70-80% of elderly people are seropositive for C. pneumoniae. Our general aim was to investigate the role of infection and inflammation in atherosclerosis both in animal and human studies. We aimed to determine how the two pathogens alter the atherosclerosis-associated parameters, and how they affect the liver inflammation and lipid composition. Furthermore, we evaluated the association between matrix metalloproteinase-8 (MMP-8), a proteinase playing a major role in inflammation, and the future cardiovascular diseases (CVD) events in a population-based cohort. For the animal experiments, we used atherosclerosis-susceptible apolipoprotein E deficient (apoE-/-) mice. They were kept in germ free conditions and fed with a normal chow diet. The bacteria were administered either intravenously (A. actinomycetemcomitans) or intranasally (C. pneumoniae). Several factors were determined from serum as well as from aortic and hepatic tissues. We also determined how cholesterol efflux, a major event in the removal of excess cholesterol from the tissues, and endothelial function were affected by these pathogens. In the human study, serum MMP-8 and its tissue inhibitor (TIMP-1) concentrations were measured and their associations during the follow-up time of 10 years with CVD events were determined. An infection with A. actinomycetemcomitans increased concentrations of inflammatory mediators, MMP production, and cholesterol deposit in macrophages, decreased lipoprotein particle size, and induced liver inflammation. C. pneumoniae infection also elicited an inflammatory response and endothelial dysfunction, as well as induced liver inflammation, microvesicular appearance and altered fatty acid profile. In the population-based cohort, men with increased serum MMP-8 concentration together with subclinical atherosclerosis (carotid artery intima media thickness > 1mm) had a three-fold increased risk for CVD death during the follow-up. The results show that infections with A. actinomycetemcomitans and C. pneumoniae induce proatherogenic changes, as well as affect the liver. These data therefore support the concept that common infections have systemic effects and could be considered as cardiovascular risk factors. Furthermore, our data indicate that, as an independent predictor of fatal CVD event, serum MMP-8 could have a clinical significance in diagnosing cardiovascular diseases.

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Epilysin (MMP-28) is the most recently identified member of the matrix metalloproteinase (MMP) family of extracellular proteases. Together these enzymes are capable of degrading almost all components of the extracellular matrix (ECM) and are thus involved in important biological processes such as development, wound healing and immune functions, but also in pathological processes such as tumor invasion, metastasis and arthritis. MMPs do not act solely by degrading the ECM. They also regulate cell behavior by releasing growth factors and biologically active peptides from the ECM, by modulating cell surface receptors and adhesion molecules and by regulating the activity of many important mediators in inflammatory pathways. The aim of this study was to define the unique role of epilysin within the MMP-family, to elucidate how and when it is expressed and how its catalytic activity is regulated. To gain information on its essential functions and substrates, the specific aim was to characterize how epilysin affects the phenotype of epithelial cells, where it is biologically expressed. During the course of the study we found that the epilysin promoter contains a well conserved GT-box that is essential for the basic expression of this gene. Transcription factors Sp1 and Sp3 bind this sequence and could hence regulate both the basic and cell type and differentiation stage specific expression of epilysin. We cloned mouse epilysin cDNA and found that epilysin is well conserved between human and mouse genomes and that epilysin is glycosylated and activated by furin. Similarly to in human tissues, epilysin is normally expressed in a number of mouse tissues. The expression pattern differs from most other MMPs, which are expressed only in response to injury or inflammation and in pathological processes like cancer. These findings implicate that epilysin could be involved in tissue homeostasis, perhaps fine-tuning the phenotype of epithelial cells according to signals from the ECM. In view of these results, it was unexpected to find that epilysin can induce a stable epithelial to mesenchymal transition (EMT) when overexpressed in epithelial lung carcinoma cells. Transforming growth factor b (TGF-b) was recognized as a crucial mediator of this process, which was characterized by the loss of E-cadherin mediated cell-cell adhesion, elevated expression of gelatinase B and MT1-MMP and increased cell migration and invasion into collagen I gels. We also observed that epilysin is bound to the surface of epithelial cells and that this interaction is lost upon cell transformation and is susceptible to degradation by membrane type-1-MMP (MT1-MMP). The wide expression of epilysin under physiological conditions implicates that its effects on epithelial cell phenotype in vivo are not as dramatic as seen in our in vitro cell system. Nevertheless, current results indicate a possible interaction between epilysin and TGF-b also under physiological circumstances, where epilysin activity may not induce EMT but, instead, trigger less permanent changes in TGF-b signaling and cell motility. Epilysin may thus play an important role in TGF-b regulated events such as wound healing and inflammation, processes where involvement of epilysin has been indicated.

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Even though mortality among preterm infants has decreased, their risk for chronic complications such as bronchopulmonary dysplasia (BPD) and neurological disability remains significant. One common risk factor for these is exposure to inflammation. The fetus may be exposed prenatally during maternal chorioamnionitis. Pre-eclampsia is also associated with low-grade maternal inflammation. Postnatally, local and systemic inflammation is present during respiratory distress syndrome (RDS). Furthermore, septic infections in the preterm infant are an important source of inflammatory stimuli and can lead to death in only a few hours. The diagnosis of septic infection is difficult, since reliable diagnostic markers are unavailable. This thesis evaluates peri- and postnatal systemic inflammation in preterm infants in septic infections, in RDS treated with mechanical ventilation and surfactant treatment, and in preterm infants prenatally exposed to chorioamnionitis and pre-eclampsia. Surface expressions of the activation markers CD11b, CD54, and CD62L, determined by flow cytometry on circulating phagocytes and T lymphocytes, serve as indicators of systemic inflammation. The main findings: I) In preterm infants with developing late-onset sepsis and fulminant necrotizing enterocolitis, a significant increase in CD11b expression on circulating phagocytes is already present on the day of onset of clinical symptoms. II) In preterm infants with RDS, circulating phagocytes become activated within hours after start of mechanical ventilation. In preterm infants treated for RDS with nasal continuous positive airway pressure, no such activation occurs. III) In preterm infants, RDS is associated during the first days of life with fewer circulating helper and cytotoxic T lymphocytes, of which the greater proportions are activated. Even greater proportions of circulating T cells are activated in infants subsequently developing BPD. IV) In preterm infants born after maternal pre-eclampsia, RDS-associated phagocyte CD11b up-regulation is greater than in preterm infants not exposed to pre-eclampsia during the first week of life. These findings suggest that I) an increase in CD11b expression on circulating phagocytes can identify preterm infants with late-onset sepsis as early as at sampling for blood culture and may thus aid in the diagnosis. II) In preterm infants with RDS, initiation of mechanical ventilation, but not the use of nasal continuous positive airway pressure, promotes a systemic inflammatory reaction; exogenous surfactant does not seem to promote inflammation. III) In addition to activation of circulating cells of the innate immunity in preterm infants with RDS, the circulating cells of the adaptive immunity are activated. The activation of adaptive immunity may link acute inflammation and development of chronic inflammation-associated problems such as BPD. IV) Maternal pre-eclampsia may prime neonatal immunity to react more strongly to postnatal stimuli. In conclusion, the preterm infant is exposed to numerous potentially injurious events such as intrauterine inflammation, respiratory distress syndrome (RDS), and systemic infections, all evoking systemic inflammation. Due to ongoing development of the lung and the brain, this may, in addition to acute injury, lead to aberrant lung and brain development and to clinical syndromes of BPD and neurologic sequelae.

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Exposure to water-damaged buildings and the associated health problems have evoked concern and created confusion during the past 20 years. Individuals exposed to moisture problem buildings report adverse health effects such as non-specific respiratory symptoms. Microbes, especially fungi, growing on the damp material have been considered as potential sources of the health problems encountered in these buildings. Fungi and their airborne fungal spores contain allergens and secondary metabolites which may trigger allergic as well as inflammatory types of responses in the eyes and airways. Although epidemiological studies have revealed an association between damp buildings and health problems, no direct cause-and-effect relationship has been established. Further knowledge is needed about the epidemiology and the mechanisms leading to the symptoms associated with exposure to fungi. Two different approaches have been used in this thesis in order to investigate the diverse health effects associated with exposure to moulds. In the first part, sensitization to moulds was evaluated and potential cross-reactivity studied in patients attending a hospital for suspected allergy. In the second part, one typical mould known to be found in water-damaged buildings and to produce toxic secondary metabolites was used to study the airway responses in an experimental model. Exposure studies were performed on both naive and allergen sensitized mice. The first part of the study showed that mould allergy is rare and highly dependent on the atopic status of the examined individual. The prevalence of sensitization was 2.7% to Cladosporium herbarum and 2.8% to Alternaria alternata in patients, the majority of whom were atopic subjects. Some of the patients sensitized to mould suffered from atopic eczema. Frequently the patients were observed to possess specific serum IgE antibodies to a yeast present in the normal skin flora, Pityrosporum ovale. In some of these patients, the IgE binding was partly found to be due to binding to shared glycoproteins in the mould and yeast allergen extracts. The second part of the study revealed that exposure to Stachybotrys chartarum spores induced an airway inflammation in the lungs of mice. The inflammation was characterized by an influx of inflammatory cells, mainly neutrophils and lymphocytes, into the lungs but with almost no differences in airway responses seen between the satratoxin producing and non-satratoxin producing strain. On the other hand, when mice were exposed to S. chartarum and sensitized/challenged with ovalbumin the extent of the inflammation was markedly enhanced. A synergistic increase in the numbers of inflammatory cells was seen in BAL and severe inflammation was observed in the histological lung sections. In conclusion, the results in this thesis imply that exposure to moulds in water damaged buildings may trigger health effects in susceptible individuals. The symptoms can rarely be explained by IgE mediated allergy to moulds. Other non-allergic mechanisms seem to be involved. Stachybotrys chartarum is one of the moulds potentially responsible for health problems. In this thesis, new reaction models for the airway inflammation induced by S. chartarum have been found using experimental approaches. The immunological status played an important role in the airway inflammation, enhancing the effects of mould exposure. The results imply that sensitized individuals may be more susceptible to exposure to moulds than non-sensitized individuals.

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Severe sepsis is associated with common occurrence, high costs of care and significant mortality. The incidence of severe sepsis has been reported to vary between 0.5/1000 and 3/1000 in different studies. The worldwide Severe Sepsis Campaign, guidelines and treatment protocols aim at decreasing severe sepsis associated high morbidity and mortality. Various mediators of inflammation, such as high mobility group box-1 protein (HMGB1) and vascular endothelial growth factor (VEGF), have been tested for severity of illness and outcome in severe sepsis. Long-term survival with quality of life (QOL) assessment is important outcome after severe sepsis. The objective of this study was to evaluate the incidence, severity of organ dysfunction and outcome of severe sepsis in intensive care treated patients in Finland (study I)). HMGB1 and VEGF were studied in predicting severity of illness, development and type of organ dysfunction and hospital mortality (studies II and III). The long-term outcome and quality of life were assessed and quality-adjusted life years and cost per one QALY were estimated (study IV). A total of 470 patients with severe sepsis were included in the Finnsepsis Study. Patients were treated in 24 Finnish intensive care units in a 4-month period from 1 November 2004 to 28 February 2005. The incidence of severe sepsis was 0.38 /1,000 in the adult population (95% confidence interval 0.34-0.41). Septic shock (77%), severe oxygenation impairment (71.4%) and acute renal failure (23.2%) were the most common organ failures. The ICU, hospital, one-year and two-year mortalities were 15.5%, 28.3%, 40.9% and 44.9% respectively. HMGB1 and VEGF were elevated in patients with severe sepsis. VEGF concentrations were lower in non-survivors than in survivors, but HMGB1 levels did not differ between patients. Neither HMGB1 nor VEGF were predictive of hospital mortality. The QOL was measured median 17 months after severe sepsis and QOL was lower than in reference population. The mean QALY was 15.2 years for a surviving patient and the cost for one QALY was 2,139 . The study showed that the incidence of severe sepsis is lower in Finland than in other countries. The short-term outcome is comparable with that in other countries, but long-term outcome is poor. HMGB1 and VEGF are not useful in predicting mortality in severe sepsis. The mean QALY for a surviving patient is 15.2 and as the cost for one QALY is reasonably low, the intensive care is cost-effective in patients with severe sepsis.

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The objective of these studies was to evaluate possible airway inflammation and remodeling at the bronchial level in cross-country skiers without a prior diagnosis of asthma, and relate the findings to patients with mild chronic asthma and patients with newly diagnosed asthma. We also studied the association of airway inflammatory changes and bronchial hyperresponsivess (BHR), and treatment effects in cross-country skiers and in patients with newly diagnosed asthma. Bronchial biopsies were obtained from the subjects by flexible bronchoscopy, and the inflammatory cells (eosinophils, mast cells, T-lymphocytes, macrophages, and neutrophils) were identified by immunohistochemistry. Tenascin (Tn) immunoreactivity in the bronchial basement membrane (BM) was identified by immunofluorescence staining. Lung function was measured with spirometry, and BHR was assessed by methacholine (skiers) or histamine (asthmatics) challenges. Skiers with BHR and asthma-like symptoms were recruited to a drug-intervention study. Skiers were given treatment (22 weeks) with placebo or budesonide (400 µg bid). Patients with newly diagnosed asthma were given treatment for 16 weeks with placebo, salmeterol (SLM) (50 µg bid), fluticasone propionate (FP) (250 µg bid), or disodium cromoglicate (DSCG) (5 mg qid). Bronchial biopsies were obtained at baseline and at the end of the treatment period. In the skiers a distinct airway inflammation was evident. In their bronchial biopsy specimens, T-lymphocyte, macrophage, and eosinophil counts were, respectively greater by 43-fold (P<0.001), 26-fold (P<0.001, and 2-fold (P<0.001) in skiers, and by 70-fold (p>0.001), 63-fold (P<0.001), and 8-fold (P<0.001) in asthmatic subjects than in controls. In skiers, neutrophil counts were more than 2-fold greater than in asthmatic subjects (P<0.05). Tn expression was higher in skiers than in controls and lower in skiers than in mild asthmatics. No significant changes were seen between skiers with or without BHR in the inflammatory cell counts or Tn expression. Treatment with inhaled budesonide did not attenuate asthma-like symptoms, the inflammatory cell infiltration, or BM Tn expression in the skiers. In newly diagnosed asthmatic patients, SLM, FP, and DSCG reduced asthma symptoms, and need for rescue medication (P<0.04). BHR was reduced by doubling doses 2.78, 5.22, and 1.35 respectively (all P<0.05). SLM and placebo had no effect on cell counts or Tn expression. FP and DSCG reduced eosinophil counts in the bronchial biopsy specimens (P<0.02 and <0.048, respectively). No significant change in tenascin expression appeared in any treatment group. Regarding to atopy, no significant differences existed in the inflammatory cell counts in the bronchial mucosa of subjects with newly diagnosed asthma or in elite cross country skiers. Tn expression in the BM was significantly higher in atopic asthma than in those with nonatopic asthma. Airway inflammation occurred in elite cross-country skiers with and without respiratory symptoms or BHR. Their inflammatory cell pattern differed from that in asthma. Infiltration with eosinophils, macrophages, and mast cells was milder, but lymphocyte counts did not differ from counts in asthmatic airways. Neutrophilic infiltration was more extensive in skiers than in asthmatics. Remodeling took place in the skiers’ airways, as reflected by increased expression of BM tenascin These inflammatory changes and Tn expression may be caused by prolonged exposure of the lower airways to inadequately humidified cold air. In skiers inflammatory changes and remodeling were not reversed with anti-inflammatory treatment. In contrast, in patients with newly diagnosed asthma, anti-inflammatory treatment did attenuate eosinophilic inflammation in the bronchial mucosa. In skiers, anti-inflammatory treatment did not attenuate BHR as it did in asthmatic patients. The BHR in skiers was attenuated spontaneously during placebo treatment, with no difference from budesonide treatment. Lower training intensity during the treatment period may explain this spontaneous decrease in BHR. The origin of BHR probably differs in skiers and in asthmatics. No significant association between BHR and inflammatory cell counts or between BHR and Tn expression was evident in cross-country skiers or asthmatic subjects. Airway remodeling differed between atopic and nonatopic asthma. As opposed to nonatopic asthma, Tn expression was higher in atopic asthma and is related to inflammatory cell densities.

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BACKGROUND: Obesity is closely associated with insulin resistance, which is a pathophysiologic condition contributing to the important co-morbidities of obesity, such as the metabolic syndrome and type 2 diabetes mellitus. In obese subjects, adipose tissue is characterized by inflammation (macrophage infiltration, increased expression insulin resistance genes and decreased expression of insulin sensitivity genes). Increased liver fat, without excessive alcohol consumption, is defined as non-alcoholic fatty liver disease (NAFLD) and also associated with obesity and insulin resistance. It is unknown whether and how insulin resistance is associated with altered expression of adipocytokines (adipose tissue-derived signaling molecules), and whether adipose tissue inflammation and NAFLD coexist independent of obesity. Genetic factors could explain variation in liver fat independent of obesity but the heritability of NAFLD is unknown. AIMS: To determine whether acute regulation of adipocytokine expression by insulin in adipose tissue is altered in obesity. To investigate the relationship between adipose tissue inflammation and liver fat content independent of obesity. To assess the heritability of serum alanine aminotransferase (ALT) activity, a surrogate marker of liver fat. METHODS: 55 healthy normal-weight and obese volunteers were recruited. Subcutaneous adipose tissue biopsies were obtained for measurement of gene expression before and during 6 hours of euglycemic hyperinsulinemia. Liver fat content was measured by proton magnetic resonance spectroscopy, and adipose tissue inflammation was assessed by gene expression, immunohistochemistry and lipidomics analysis. Genetic factors contributing to serum ALT activity were determined in 313 twins by statistical heritability modeling. RESULTS: During insulin infusion the expression of insulin sensitivity genes remains unchanged, while the expression of insulin resistance genes increases in obese/insulin-resistant subjects compared to insulin-sensitive subjects. Adipose tissue inflammation is associated with liver fat content independent of obesity. Adipose tissue of subjects with high liver fat content is characterized infiltrated macrophages and increased expression of inflammatory genes, as well as by increased concentrations of ceramides compared to equally obese subjects with normal liver fat. A significant heritability for serum ALT activity was verified. CONCLUSIONS: Effects of insulin infusion on adipose tissue gene expression in obese/insulin-resistant subjects are not only characterized by hyporesponse of insulin sensitivity genes but also by hyperresponse of insulin resistance and inflammatory genes. This suggests that in obesity, the impaired insulin action contributes or self-perpetuates alterations in adipocytokine expression in adipose tissue. Adipose tissue inflammation is increased in subjects with high liver fat compared to equally obese subjects with normal liver fat content. Concentrations of ceramides, the putative mediators of insulin resistance, are increased in adipose tissue in subjects with high liver fat. Genetic factors contribute significantly to variation in serum ALT activity, a surrogate marker of liver fat. These data imply that adipose tissue inflammation and increased liver fat content are closely interrelated, and determine insulin resistance even independent of obesity.

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The occurrence of gestational diabetes (GDM) during pregnancy is a powerful sign of a risk of later type 2 diabetes (T2D) and cardiovascular diseases (CVDs). The physiological basis for this disease progression is not yet fully understood, but increasing evidence exists on interplay of insulin resistance, subclinical inflammation, and more recently, on unbalance of the autonomic nervous system. Since the delay in development of T2D and CVD after GDM ranges from years to decades, better understanding of the pathophysiology of GDM could give us new tools for primary prevention. The present study was aimed at investigating the role of the sympathetic nervous system (SNS) in GDM and its associations with insulin and a variety of inflammatory cytokines and coagulation and fibrinolysis markers. This thesis covers two separate study lines. Firstly, we investigated 41 women with GDM and 22 healthy pregnant and 14 non-pregnant controls during the night in hospital. Blood samples were drawn at 24:00, 4:00 and 7:00 h to determine the concentrations of plasma glucose, insulin, noradrenaline (NA) and adrenomedullin, markers of subclinical inflammation, coagulation and fibrinolysis variables and platelet function. Overnight holter ECG recording was performed for analysis of heart rate variability (HRV). Secondly, we studied 87 overweight hypertensive women with natural menopause. They were randomised to use a central sympatholytic agent, moxonidine (0.3mg twice daily), the β-blocking agent atenolol (50 mg once daily+blacebo once daily) for 8 weeks. Inflammatory markers and adiponectin were analysed at the beginning and after 8 weeks. Activation of the SNS (increase in NA, decreased HRV) was seen in pregnant vs. non-pregnant women, but no difference existed between GDM and normal pregnancy. However, modulation (internal rhythm) of HRV was attenuated in GDM. Insulin and inflammatory cytokine levels were comparable in all pregnant women but nocturnal variation of concentrations of C-reactive protein, serum amyloid A and insulin were reduced in GDM. Levels of coagulation factor VIII were lower in GDM compared with normal pregnancy, whereas no other differences were seen in coagulation and fibrinolysis markers. No significant associations were seen between NA and the studied parameters. In the study of postmenopausal women, moxonidine treatment was associated with favourable changes in the inflammatory profile, seen as a decrease in TNFα concentrations (increase in atenolol group) and preservation of adiponectin levels (decrease in atenolol group). In conclusion, our results did not support our hypotheses of increased SNS activity in GDM or a marked association between NA and inflammatory and coagulation markers. Reduced biological variation of HRV, insulin and inflammatory cytokines suggests disturbance of autonomic and hormonal regulatory mechanisms in GDM. This is a novel finding. Further understanding of the regulatory mechanisms could allow earlier detection of risk women and the possibility of prevention. In addition, our results support consideration of the SNS as one of the therapeutic targets in the battle against metabolic diseases, including T2D and CVD.

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Asthma is a chronic inflammatory disorder of the airways. Remodelling in asthma is defined as the structural changes seen in the airways of asthmatics in comparison to healthy controls. Progressive loss of lung function also seen in asthma might be caused by remodelling. The research aims of this thesis were to investigate inflammation and remodelling in the airways of different types of asthmatics and smokers. The association between inflammation and remodelling was also examined in a mouse model of allergic airway inflammation. Healthy smokers showed increased numbers of macrophages in the BAL with no changes in the inflammatory cells in biopsies. Macrophages seemed to be quite quiescent, since mRNA expression for a wide variety of inflammatory mediators, especially chemokines CCL3, CCL4, CCL5 and CCL20, secreted by macrophages was significantly lower than in healthy non-smokers. Attenuated macrophage activity in the airway lumen may render smokers more susceptible to airway infections and have an impact on the development of other airway pathology. Patients with diisocyanate-induced asthma (DIA) on inhaled corticosteroids (ICS) who still had non-specific bronchial hyperreactivity (NSBHR) at the end of the follow-up showed increased expression of TNF-α, IL-6 and IL-15 mRNA in BAL cells compared to those without NSBHR. In addition to being markers for poor prognosis and possible slight glucocorticoid resistance, these cytokines might aid in guiding the treatment of DIA. The increase in the thickness of tenascin-C layer in the bronchial basement membrane (BM) was much less than usually seen in other types of asthma, which might not make tenascin-C a good marker for DIA. OVA-induced tenascin-C expression in the lung was attenuated in STAT4-/- mice with impaired Th1-type immunity compared to WT mice. Interestingly, STAT6-/- mice with impaired Th2-type immunity showed tenascin-C expression levels similar to those of WT mice. The clearest difference between these two knockout strains in response to OVA was that STAT4-/- mice exhibited no upregulation of IFN-γ and TNF-α mRNA expression. Thus, tenascin-C expression was unexpectedly more related to Th1 type reactions. In vitro studies confirmed the results. Human fibroblasts stimulated by TNF-α and IFN-γ showed increased expression of tenascin-C. Patients with newly diagnosed asthma showed increased expression of laminin α2 in the bronchial BM in comparison to patients with asthma symptoms only and healthy controls. Both patients with asthma and those with only asthma symptoms showed increased expression of the laminin β2 chain in comparison to controls. Thus, laminin α2 expression differentiated patients with clinical asthma from patients with symptoms only. Furthermore, the expression of laminin α2 and β2 was associated with NSBHR, linking very specific remodelling events to clinical findings.

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This study examines boundaries in health care organizations. Boundaries are sometimes considered things to be avoided in everyday living. This study suggests that boundaries can be important temporally and spatially emerging locations of development, learning, and change in inter-organizational activity. Boundaries can act as mediators of cultural and social formations and practices. The data of the study was gathered in an intervention project during the years 2000-2002 in Helsinki in which the care of 26 patients with multiple and chronic illnesses was improved. The project used the Change Laboratory method that represents a research assisted method for developing work. The research questions of the study are: (1) What are the boundary dynamics of development, learning, and change in health care for patients with multiple and chronic illnesses? (2) How do individual patients experience boundaries in their health care? (3) How are the boundaries of health care constructed and reconstructed in social interaction? (4) What are the dynamics of boundary crossing in the experimentation with the new tools and new practice? The methodology of the study, the ethnography of the multi-organizational field of activity, draws on cultural-historical activity theory and anthropological methods. The ethnographic fieldwork involves multiple research techniques and a collaborative strategy for raising research data. The data of this study consists of observations, interviews, transcribed intervention sessions, and patients' health documents. According to the findings, the care of patients with multiple and chronic illnesses emerges as fragmented by divisions of a patient and professionals, specialties of medicine and levels of health care organization. These boundaries have a historical origin in the Finnish health care system. As an implication of these boundaries, patients frequently experience uncertainty and neglect in their care. However, the boundaries of a single patient were transformed in the Change Laboratory discussions among patients, professionals and researchers. In these discussions, the questioning of the prevailing boundaries was triggered by the observation of gaps in inter-organizational care. Transformation of the prevailing boundaries was achieved in implementation of the collaborative care agreement tool and the practice of negotiated care. However, the new tool and practice did not expand into general use during the project. The study identifies two complementary models for the development of health care organization in Finland. The 'care package model', which is based on productivity and process models adopted from engineering and the 'model of negotiated care', which is based on co-configuration and the public good.

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The aim of the thesis was to compare the correspondence of the outcome a computer assisted program appearance compared to the original image. The aspect of the study was directed to embroidery with household machines. The study was made from the usability point of view with Brother's PE-design 6.0 embroidery design programs two automatic techniques; multicoloured fragment design and multicoloured stitch surface design. The study's subject is very current because of the fast development of machine embroidery. The theory is based on history of household sewing machines, embroidery sewing machines, stitch types in household sewing machines, embroidery design programs as well as PE-design 6.0 embroidery design program's six automatic techniques. Additionally designing of embroidery designs were included: original image, digitizing, punching, applicable sewing threads as well as the connection between embroidery designs and materials used on embroidery. Correspondences of sewn appearances were examined with sewing experimental methods. 18 research samples of five original image were sewn with both techniques. Experiments were divided into four testing stages in design program. Every testing stage was followed by experimental sewing with Brother Super Galaxie 3100D embroidery machine. Experiments were reported into process files and forms made for the techniques. Research samples were analysed on images syntactic bases with sensory perception assessment. Original images and correspondence of the embroidery appearances were analysed with a form made of it. The form was divided into colour and shape assessment in five stage-similarity-scale. Based on this correspondence analysis it can be said that with both automatic techniques the best correspondence of colour and shape was achieved by changing the standard settings and using the makers own thread chart and edited original image. According to the testing made it is impossible to inform where the image editing possibilities of the images are sufficient or does the optimum correspondence need a separate program. When aiming at correspondence between appearances of two images the computer is unable to trace by itself the appearance of the original image. Processing a computer program assisted embroidery image human perception and personal decision making are unavoidable.

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Atherosclerosis is a disease of the arteries; its characteristic features include chronic inflammation, extra- and intracellular lipid accumulation, extracellular matrix remodeling, and an increase in extracellular matrix volume. The underlying mechanisms in the pathogenesis of advanced atherosclerotic plaques, that involve local acidity of the extracellular fluid, are still incompletely understood. In this thesis project, my co-workers and I studied the different mechanisms by which local extracellular acidity could promote accumulation of the atherogenic apolipoprotein B-100 (apoB-100)-containing plasma lipoprotein particles in the inner layer of the arterial wall, the intima. We found that lipolysis of atherogenic apoB-100-containing plasma lipoprotein particles (LDL, IDL, and sVLDL) by the secretory phospholipase A2 group V (sPLA2-V) enzyme, was increased at acidic pH. Also, the binding of apoB-100-containing plasma lipoprotein particles to human aortic proteoglycans was dramatically enhanced at acidic pH. Additionally, lipolysis by sPLA2-V enzyme further increased this binding. Using proteoglycan-affinity chromatography, we found that sVLDL lipoprotein particles consist of populations, differing in their affinities toward proteoglycans. These populations also contained different amounts of apolipoprotein E (apoE) and apolipoprotein C-III (apoC-III); the amounts of apoC-III and apoE per particle were highest in the population with the lowest affinity toward proteoglycans. Since PLA2-modification of LDL particles has been shown to change their aggregation behavior, we also studied the effect of acidic pH on the monolayer structure covering lipoprotein particles after PLA2-induced hydrolysis. Using molecular dynamics simulations, we found that, in acidity, the monolayer is more tightly packed laterally; moreover, its spontaneous curvature is negative, suggesting that acidity may promote lipoprotein particles fusion. In addition to extracellular lipid accumulation, the apoB-100-containing plasma lipoprotein particles can be taken up by inflammatory cells, namely macrophages. Using radiolabeled lipoprotein particles and cell cultures, we showed that sPLA2-V-modification of LDL, IDL, and sVLDL lipoproteins particles, at neutral or acidic pH, increased their uptake by human monocyte-derived macrophages.