| 1. |
- Eriksson, Therese, 1979-
(author)
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Organelle movement in melanophores: Effects of Panax ginseng, ginsenosides and quercetin
- 2009
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Licentiate thesis (other academic/artistic)abstract
- Panax ginseng is a traditional herb that has been used for over 2000 years to promote health and longevity. Active components of ginseng include ginsenosides, polysaccharides, flavonoids, polyacetylenes, peptides, vitamins, phenols and enzymes, of which the ginsenosides are considered to be the major bioactive constituents. Although widely used, the exact mechanisms of ginseng and its compounds remain unclear. In this thesis we use melanophores from Xenopus laevis to investigate the effects of Panax ginseng extract G115 and its constituents on organelle transport and signalling. Due to coordinated bidirectional movement of their pigmented granules (melanosomes), in response to defined chemical signals, melanophores are capable of fast colour changes and provide a great model for the study of intracellular transport. The movement is regulated by alterations in cyclic adenosine 3’:5’-monophosphate (cAMP) concentration, where a high or low level induce anterograde (dispersion) or retrograde (aggregation) transport respectively, resulting in a dark or light cell. Here we demonstrate that Panax ginseng and its constituents ginsenoside Rc and Rd and flavonoid quercetin induce a concentration-dependent anterograde transport of melanosomes. The effect of ginseng is shown to be independent of cAMP changes and protein kinase A activation. Upon incubation of melanophores with a combination of Rc or Rd and quercetin, a synergistic increase in anterograde movement was seen, indicating cooperation between the ginsenoside and flavonoid parts of ginseng. Protein kinase C (PKC) inhibitor Myristoylated EGF-R Fragment 651-658 decreased the anterograde movement stimulated by ginseng and ginsenoside Rc and Rd. Moreover, ginseng, but not ginsenosides or quercetin, stimulated an activation of 44/42-mitogen activated protein kinase (MAPK), previously shown to be involved in both aggregation and dispersion of melanosomes. PKC-inhibition did not affect the MAPK-activation, suggesting a role for PKC in the ginseng- and ginsenoside-induced dispersion but not as an upstream activator of MAPK.
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| 2. |
- Davidsson, Anette, 1960-
(author)
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Exhaled Breath Condensate in Obstructive Lung Diseases : A Methodological study
- 2009
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Doctoral thesis (other academic/artistic)abstract
- Asthma and chronic obstructive pulmonary disease (COPD) are two common inflammatory airway diseases characterized by airway inflammation and mucus hypersecretion. Prediction of the outcome of these diseases may not be performed and the need for non-invasive diagnostic tools capable of identifying inflammation in asthma and COPD becomes therefore obvious. Validation, sensitivity and specificity of most non-invasive methods to detect and monitor inflammatory responses in airways are poor and there is a great need to identify and standardize less invasive, or non-invasive methods for investigation of airway inflammation.Epithelial lining fluid (ELF) covers the airway surface and contains soluble and insoluble inflammatory cell products and plasma proteins originating and passively transferred from the underlying tissue. Airborne aerosol particles containing ELF saturated with water may be recovered in exhaled air by allowing the air to pass a cold surface, creating exhaled breath condensate (EBC). EBC may then be analysed for various components of interest.The aims of this thesis were (1) to explore whether a certain profile of inflammatory cell markers in EBC, saliva or serum may be identified in patients with allergic asthma or COPD, (2) to evaluate the efficacy and reproducibility of a measurable marker in EBC using either of the two condensers ECoScreen or RTube and (3) to evaluate the value of chlorine concentrations in EBC as well as reproducibility of assessments of certain compounds in EBC.Material and methods: Thirty-six patients with asthma, 49 smokers or ex-smokers and 25 healthy volunteers participated in three clinical studies. In addition, efficacy, reproducibility and comparison of the two condensers were studied in an ex vivo set up using aerosols of solutions of saline, myeloperoxidase (MPO) or human neutrophil lipocalin (HNL). Aerosol boluses were transferred by means of a servo ventilator to either of the two condensers. Concentrations of chlorine (presumed to be a marker of mucous secretion) in EBC or saliva were analyzed by means of a sensitive coulometric technique (AOX). The inflammatory cell markers histamine, MPO, HNL, lysozyme, cysteinyl-leukotrienes (CysLT) and eosinophil cationic protein (ECP) were analysed in EBC, saliva and/or serum by means of ELISA, RIA, EIA or immunochemical fluorescence methods, respectively. Lung function tests, including diffusion capacity were measured by standard techniques according to clinical routines.Results and Conclusions: Chlorine measurements served as the main tool in our tests and intra-assay variability <10% was recorded. However, flow dependency, temperature dependency, substance dependency and concentration dependency characterized yields of EBC. Despite acceptable analytical precision, low concentration levels of inflammation markers, biological variability and occasionally contamination with saliva mean that the feasibility of the EBC method is limited. Despite biological variability, concentrations of chlorine in EBC were significantly higher during than after a mild pollen season, suggesting that chlorine concentrations in EBC are a sensitive marker of allergic airway inflammation. A vast number of confounding factors made interpretations of EBC data obtained from COPD and non-COPD patients difficult and traditional diagnostic tools, such as diffusion capacity (DLCO) and serum lysozyme appeared to best discriminate between COPD and non-COPD.
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| 3. |
- Lech, Börje
(author)
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Consciousness about own and others’ affects
- 2012
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Doctoral thesis (other academic/artistic)abstract
- It is essential for individuals’ well-being and relationships that they have the ability to consciously experience, express and respond to their own and others’ affects. The validity of a new conception of affect consciousness (AC), incorporating consciousness of both own and others’ affects, was investigated in this thesis. The clinical usefulness of the new conception was explored and an interview (affect consciousness interview – self/other; ACI-S/O) intended to capture this new definition was validated. In study I the interrater reliability and the concurrent validity of the ACI-S/O were assessed and found to be acceptable. There were significant differences in all variables of ACI-S/O between the four groups that participated in the study. Joy and interest had the highest ratings in all groups and guilt and shame had the lowest. By means of a factor analysis, two factors, labeled “general affect consciousness” and “consciousness about shame and guilt,” were obtained. General affect consciousness was related to different aspects of relational and emotional problems and possibly protection against them. In study II the clinical implications of AC were further explored in relation to eating disorders (ED). The level of AC in the ED group was compared with a comparable non-clinical group. The relation between AC and aspects of ED pathology were explored, as well as whether AC should be seen as a state or trait in patients diagnosed with ED. ACI-S/O was not significantly related to ED pathology or general psychological distress. There were no significant differences in AC between the different sub-diagnoses of ED but there were between the ED group and the non-clinical group. Significant pre-post correlations for both factors of ACI-S/O were found, indicating that AC could be seen as a stable dimension that might be important for ED pathology but is unrelated to ED symptoms. In study III the relationship between AC and self-reported attachment style (ASQ) was explored in a non-clinical group and three patient groups. There were significant correlations between all scores on ACI- S/O and the ASQ, with the exception of consciousness about guilt. Multiple regression analyses showed that AC, and especially others’ affects, contributed significantly to the ASQ subscales. AC and in particular own joy and others’ guilt and anger seem to be of importance for attachment style. In study IV the importance of AC for the treatment process was explored. Patients’ AC before therapy was significantly correlated with patients’ positive feelings towards their therapists but not with their alliance ratings. Patients’ warm and positive feelings were related to pre-therapy AC, whereas negative feelings were related to low alliance ratings in the previous sessions.
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| 4. |
- Andersson-Östling, Henrik C.M. 1966-
(author)
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Mechanical Properties of Welds at Creep Activation Temperatures
- 2010
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Doctoral thesis (other academic/artistic)abstract
- Welds in materials intended for service at temperatures above the creep activation temperature often develop damage before the base metal. The weld is a discontinuity in the material and stresses and strains often accumulate in the weld. Knowledge of the properties of the weld is essential to the safe operation of the component containing the weld. The work in this thesis has been aimed at the study of welds in service at high temperatures: The work is divided into two main chapters. The first chapter deals with welds in stainlesssteels and dissimilar metal welds and includes three papers, and the second chapter dealswith welds in copper intended for nuclear waste disposal, also including three papers. Common to both parts is that the temperature is high enough for most of the damage in the welds to result from creep. In the first part the role of the weld microstructure on the creep crack propagation properties has been studied. Experiments using compact tension specimens have been performed on service exposed, low alloyed heat resistant steels. The results show good correlation with the crack tip parameter, C*, during steady state creep crack growth. The test methodology has also been reviewed and sensitive test parameters have been identified. The results from the creep crack propagation tests on service exposed material has been modeled using uniaxial creep data on both new and ex-service material. The development of the weld microstructure in a dissimilar metal weld between two heat resistant steels has also been investigated. A weld was made between one ferritic and one martensitic steel and the development of the microstructure during welding and post-weldheat treatments has been studied. The results show that the carbon depleted zone that develops near the weld metal in the lower alloyed steel depends on the formation and dissolution of the M23C6-carbide. Variations of the weld parameters and the post-weld heat treatment affect the size and shape of this zone. The process has been successfully modeled by computer simulation. The second part focuses on oxygen free copper intended for nuclear waste disposal containers. The containers are made with an inner core of cast nodular iron and an outer core of copper for corrosion protection. The copper shell has to be welded and two weld methods has been tested, electron beam welding and friction stir welding. Creep specimens taken from both weld types have been tested as have base metal specimens. The technical specifications of the waste canisters demand that the creep ductility of both the copper shell and the welds has to be as high as possible. The creep test results show that base material doped with at least 30 ppm phosphorus has high creep ductility, and friction stir welds made from this material has almost as high creep strength and creep ductility. Copper without phosphorus does not exhibit the same ductility. The creep properties evaluated from testing has been modeled and extrapolated for the intended purpose
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| 5. |
- Ekeblad, Annika
(author)
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A Randomized Trial of Interpersonal Psychotherapy and Cognitive Behavioral Therapy for Major Depressive Disorder : Predictors of process and outcome
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Interpersonal Psychotherapy (IPT) and Cognitive Behavioral Therapy (CBT) are both evidence-based treatments for Major Depressive Disorder (MDD). Several head-to-head comparisons between these methods have been made, most of them in the US. There is a need for more trials in different treatment settings. This thesis is based on a randomized controlled trial of CBT and IPT for MDD in a community-based psychiatric outpatient clinic. In the trial, treatment outcome and mentalization change was compared between the methods. In addition, the significance of pre-treatment mentalization for subsequent alliance and outcome was analyzed. Ninety-six patients, about half of them with personality disorders, were randomized to 14 sessions of CBT or IPT. The hypothesis was that IPT would not be inferior to CBT which was confirmed. CBT had a significantly higher drop-out rate. Initial capacity for mentalization predicted alliance and outcome in both IPT and CBT. The level of mentalization was changed in IPT but not in CBT
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| 6. |
- Holmqvist Larsson, Mattias, 1977-
(author)
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Rupture and Repair in the Working Alliance : Relation to Psychotherapy Outcome and Within-Session Interaction
- 2019
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Doctoral thesis (other academic/artistic)abstract
- Ruptures and repairs are processes related to shifts in the collaborative relationship Cthe working allianceJ between patient and therapist in psychotherapy. Ta study ruptures and repairs is one way ta disentangle mechanisms that might underlie the association between the working alliance and psychotherapy outcome. The overarching aim af this thesis was ta analyze the clinical relevance af the rupture and repair concepts at different process levels. The same three alliance patterns were investigated in the three empirical studies: the rupture pattern, the repair pattern, and the no-rupture/stable pattern. The analyses af the alliance patterns moved fromwhole treatments ta session segments. In Study I ruptures were found ta be associated with worse outcomes than treatments without ruptures. Repairs were, in longer therapies, shown ta be related ta better outcomes than norupture treatments. In Study Il it was found that the three alliance patterns could be discerned within sessions. Ruptures and repairs within sessions were found ta be associated with patient-ratings af the working alliance. In Study 111 the alliance patterns were found ta be related ta different interaction patterns within sessions. In these analyses, importont patient contributions ta repairs af ruptures were found.
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| 7. |
- Johansson, Elisabeth, 1969-
(author)
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Effect of ozone on dental caries and on cariogenic microorganisms
- 2012
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Doctoral thesis (other academic/artistic)abstract
- There are a number of unanswered questions regarding new caries preventive methods such as ozone treatment as well as novel caries detection methods that monitor and evaluate these preventive methods. This thesis seeks answers to some of these questions.Aims: Paper I investigates the in vitro sealing capacity of a novel ozone delivery system and its re-suction capacity. Paper II studies the in vitro antibacterial effect of ozone on cariogenic bacterial species with and without the presence of saliva and its possible effect on the saliva proteins. Paper III assesses the in vitro validity of laser-induced fluorescence (LF) measurements, visual inspection (colour), and tactile examination (surface texture) on root caries lesions and correlates these with histopathological measurements of lesion depths. In addition, Paper III investigates how inter-device, inter-examiner, and intra-examiner levels influence LF reading agreements and whether lesion colour and surface texture influences LF readings. Paper IV evaluates the in vivo effect of ozone and fluoride varnish treatments on occlusal caries in primary molars.Material and methods: Paper I: Full ozone application cycles, including the re-suction period, and interrupted cycles with displacement of the cup during the delivery cycle were studied using an ozone air analyser. Paper II: Ozone gas was exposed to the bacteria in the solution’s buffer and saliva via a tube connected to the ozone generator for 10, 30, and 60 seconds. Paper III: Calibrated examiners assessed lesion colour and surface texture and performed measurements with two LF devices for three separate one-week intervals. Sections (300µm thick) of 64 out of 93 teeth were obtained and examined under a microscope. Lesion depth was assessed with two references: from the delineated borderline of the original exposed root surface (ref I) or, if loss of surface continuity, the absolute lesion depth (ref II). Paper IV: The split mouth study was conducted in two parts. The participants in part A were children (mean age 4.8 years) with medium-high caries risk. Inclusion criteria were bilateral matched pairs of cavitated or non-cavitated occlusal lesions in primary molars (Ekstrand index score ≤ 3). Children in part B (mean age 4.5 years) with low-medium caries risk had pairs of non-cavitated lesions only (Ekstrand index score ≤ 2a). The assessments and treatments with ozone and fluoride varnish were performed at baseline and at three, six, and nine months. At the 12-month follow-up, only assessments were performed.Results: Paper I: Ozone leakage levels varied between 5.2 and 9.8 µg/m3. Paper II: In the salt buffer, 92%, 73%, and 64% of the initial numbers of A. naeslundii, S. mutans, and L. casei, respectively, were killed after 10 s ozone exposure and approximately 99.9% of the bacteria were dead after a 60 s exposure. After 10 and 30 s but not after 60 s exposure to ozone, S. mutans and L. casei were less efficiently killed in saliva compared to in the salt buffer. Various saliva proteins were degraded by ozone after the 60 s exposure. Paper III: The correlation between LF readings and histological depth was low with values ranging from 0.22 (p ˃ 0.05) to 0.31 (p < 0.05). The LF devices were significantly correlated with discolouration and with a surface texture denoted as hard. A significant correlation was found between colour and histological depth. No significant correlation was found between surface texture and histological depth. The reliability, evaluated as intra-class correlation coefficient, was 0.99 for intra-examiner, 0.97 for inter-examiner, and 0.98 inter-device level. Large differences were found between two consecutive measurements and high measurement errors indicated considerable deviation of individual measurements.Paper IV: In the first 15 pairs of part A, eight lesions treated with ozone and nine treated with fluoride, including all cavitated lesions, progressed to failure, i.e., required operative treatment during the study time. Due to non-acceptable results, the sample collection was discontinued because of ethical reasons. In part B, of 35 pairs, one of the ozone treated lesions failed at 12 months. A small shift towards increased VI scores was recorded for both ozone and fluoride lesions in this second part.Conclusions:- The ozone delivery system can be considered a safe system with low leakage levels in air, also with accidental displacements.- The cariogenic species S. mutans, L. casei, and A. naeslundii were sensitive to ozone gas treatment. The presence of saliva hampered the antibacterial effect of ozone.A low correlation between the LF readings and the histopathological depth of root caries lesions was shown. The LF device was found not to be appropriate for application to root caries diagnosis.- Neither ozone nor fluoride varnish treatments arrested the progression of cavitated occlusal caries lesions. In low and medium caries risk children non-cavitated occlusal lesions remained mainly unchanged during the study period. No difference in the effect of ozone and fluoride varnish treatments on occlusal caries in primary molars was seen.
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| 8. |
- Kashif, Muhammad
(author)
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Integrated Computational and Experimental Approaches for Accelerated Drug Combination Discovery and Development : Applications in Cancer Pharmacology
- 2015
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Doctoral thesis (other academic/artistic)abstract
- Today the norm in modern cancer treatment is to use different forms of drug combinations. Recently anti-cancer treatment using drug combinations has gained increased attention due to the outstanding pharmacotherapeutic opportunities provided by combination therapies. However, the potential of this field is largely unexplored, partly due to the complexities associated with the astronomical number of possible combinations and partly due to the lack of means for quantifying clinically relevant adverse side effects in the early stages of the combination discovery and development process. This has resulted in relatively limited progress in this area. Motivated by this unfortunate state-of-affairs, the research reported in this thesis was aimed at developing and implementing computational and experimental methods to facilitate and accelerate the discovery and development of anti-cancer therapies. In paper I, the largely overlooked concept of therapeutic synergy is re-introduced and demonstrated to be useful already at the level of combination discovery by taking both curative and adverse effects into account. In paper II, a semiautomatic combination discovery platform was developed based on a tailored programming of a pipetting robot system and application of a new in-house developed combination search algorithm, the therapeutic algorithmic combinatorial screen (TACS) algorithm. TACS seems to be the first algorithm of its kind that takes experimental variability into account during the iterative search process. The semiautomatic hardware platform along with TACS can perform de novo or knowledge based combination drug discovery and development without brute force comprehensive search efforts. One promising discovery made using this platform is a combination of the drugs 17-AAG, afungin and trichostatin a for treatment of colorectal cancer carcinoma (CRC). In paper III, an algorithm is developed and applied in order to use single drug induced systemic gene expression profiles for rational drug combination design by assuming additive combination effects. The resulting algorithm, combo-CMap, is applied and validated using a slightly extended version of the freely available Connectivity Map (CMap) database which is currently containing 6190 chemically induced mRNA gene expression signatures. In paper IV, a software (R package) was developed and applied to perform improved synergy/antagonism analysis, in particular joint Loewe and Bliss analyses while taking associated experimental variability into account using non-parametric statistics including bootstrap intervals. Applying this software to the synergy analysis of interaction effects among clinically used and/or relevant drugs in CRC cell lines revealed complex patterns of synergy and antagonism. In conclusion, the work presented here offers important contributions and findings that may accelerate and/or improve different parts of the field of drug combination discovery and development.
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| 9. |
- Laskar, Amit, 1984-
(author)
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Cell response to imaging contrast agents suggested for atherosclerotic plaque imaging
- 2013
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Doctoral thesis (other academic/artistic)abstract
- Oxysterols are the major cytotoxic components of oxidized low-density lipoprotein (OxLDL) that accumulate in atherosclerotic plaques. Their uptake by macrophages ensue foam cell formation, atherogenesis and plaque progression. Magnetic resonance imaging (MRI) has grown as a modality to track such intra-plaque developments by using intracellular contrast agents. The focus of this study was to evaluate the effects of two contrast agents; manganese based mangafodipir (TeslascanTM) and iron based super-paramagnetic iron oxide nanoparticles (SPION, ResovistTM) on cell functions and examined their interaction with oxysterol laden cells.Mangafodipir has antioxidant property and provides protection against oxidative stress. The chemical structure of mangafodipir comprises of organic ligand fodipir (Dipyridoxyl diphosphate, Dp-dp) and Mn (manganese). Mangafodipir is readily metabolized within the body to manganese dipyridoxyl ethyldiamine (MnPLED) after an intravenous injection. MnPLED has superoxide dismutase (SOD) mimetic activity, and Dp-dp has iron chelating effects. The second contrast agent tested in this study is ResovistTM. These SPION are primarily ingested by macrophages and accumulated in lysosomes where they are gradually degraded ensuing increased cellular iron.In paper I, we examined whether the above-noted effects of mangafodipir could be utilized to prevent 7β-hydroxycholesterol (7βOH) induced cell death. We found that mangafodipir prevents 7βOH induced cell death by attenuating reactive oxygen species (ROS) and by preserving lysosomal membrane integrity and mitochondrial membrane potential.The second part of this study (paper II) was designed to identify the pharmacologically active part of mangafodipir, which exerts the above-noted effects. We compared the activity of parent compound (mangafodipir) with MnPLED and Dp-dp. We found that mangafodipir; MnPLED and Dp-dp provide similar cyto-protection against 7βOH induced cell death. These results suggest that MnPLED and Dp-dp both contribute to the pharmacologically active part of mangafodipir.In paper III, we aimed to examine the interaction of SPION with monocytes and macrophages exposed or not to atheroma relevant oxysterols. We demonstrate that SPION loading up-regulates cellular levels of cathepsin and ferritin and induces membranous ferroportin expression. Additionally, SPION incites secretion of ferritin and both pro-inflammatory and anti-inflammatory cytokines. Moreover, exposure to oxysterols resulted in a reduced SPION uptake by cells, which may lead to inefficient targeting of such cells. Although SPION uptake was reduced, the ingested amounts significantly up-regulated the expression of 7βOH induced cathepsin B, cathepsin L and ferritin in cells, which may further aggravate atherogenesis.The fourth part of the study (paper IV) was designed to examine the interaction of SPION with macrophage subtypes and compare the cellular effects of coated and uncoated iron-oxide nanoparticles. We found that iron in SPION induces a phenotypic shift in THP1 M2 macrophages towards a macrophage subtype characterized by upregulated intracellular levels of CD86, ferritin and cathepsin L. Differential levels of these proteins among macrophage subtypes might be important to sustain a functional plasticity. Additionally, uncoated iron-oxide nanoparticles induced dose dependent cell death in macrophages, which elucidates the potential cyto-toxicity of iron in iron-oxide nanoparticles.In conclusion, evidence is provided in this study that intracellular MRI contrast agents have the potential to modulate cell functions. The study reveals a therapeutic potential of mangafodipir, which could be utilized for future development of contrast agents with both diagnostic and curative potentials. Additionally, we found that surface coating in SPION may provide cell tolerance to iron toxicity by modulation of cellular iron metabolism and cell functions. Such alterations in cellular metabolism call for careful monitoring and also highlight new concepts for development of iron containing nanoparticles. A reduced uptake of SPION by atheroma relevant cells justifies development of functionalized SPION to target such cells in atherosclerotic plaques.
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| 10. |
- Ljungberg, Liza, 1980-
(author)
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Angiotensin-Converting Enzyme : Effects of Smoking and Other Risk Factors for Cardiovascular Diseases
- 2009
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Licentiate thesis (other academic/artistic)abstract
- Cardiovascular diseases (CVDs) are the most common cause of death in Western countries. Smoking, hypertension, diabetes mellitus and hypercholesterolemia are considered as major risk factors. However, the underlying mechanisms by which these factors cause CVDs are not entirely clear. Angiotensin-converting enzyme (ACE) is a key enzyme in the renin-angiotensin-aldosterone system, converting angiotensin I to the vasoactive peptide angiotensin II. Besides being an important factor for normal regulation of blood pressure, ACE appears to be involved in the pathogenesis of atherosclerosis. Previous studies have shown an upregulation of ACE in atherosclerotic plaques. There is genetic polymorphism in the ACE gene (ACE I/D polymorphism) which is strongly connected to the levels of ACE in plasma, but has also been associated with higher risk for cardiovascular diseases. The aim of this thesis was to investigate ACE in vitro and in vivo, in relation to cardiovascular risk factors and CVDs. The results showed that nicotine and nicotine metabolites increase ACE activity in human endothelial cells in vitro. Smoking was associated with increased plasma ACE levels. This effect might be mediated by nicotine and nicotine metabolites. These results could explain one cellular mechanism by which smoking exerts negative effect on the vascular system. Extract of oral snuff inhibited ACE in human endothelial cells and in serum, whereas extract of cigarette smoke had no effect on endothelial ACE. If these results have any physiological relevance remains to be investigated. Cardiovascular risk factors and CVDs were associated with increased levels of ACE in plasma. No association between ACE D/D genotype and CVDs was found. Based on these results we suggest that an increased level of ACE, rather than ACE genotype, is associated with increased risk for CVDs.
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