| 1. |
- Klasson, Maria, 1977-
(författare)
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Cobalt in the hard metal production industry : exposure via inhalation and skin and the inflammatory response in human keratinocytes
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cobalt is a strong sensitizer and can cause contact allergy upon both direct contact or from airborne exposure on the skin. In the skin, keratinocytes are the first cells to come in contact with the metal and will react and respond to the danger by triggering an alarm system resulting in an inflammatory response in the skin. Keratinocytes have been shown to produce IL-1β, which is one of the most potent inflammatory agents in our body and is associated with a variety of diseases.The aims of this thesis was to investigate cobalt air concentrations for different particle fractions for possible use as proxies for other article measures and to examine if cobalt skin and inhalable air exposure contributes to uptake. Also, to investigate the effect of cobalt on cultured human keratinocyte cell viability, pro-inflammatory cytokine/chemokine release and NLRP3 inflammasome activation using cells cultured at low or high calcium (the latter yielding a more differentiated cell type).Air exposure to cobalt was found in all departments and for all work tasks in the hard metal production facility and exposures were in general below the Swedish OEL for inhalable cobalt. The highest exposure levels were found in the powder production department and for laboratory and furnace work. Good correlations for the mass based measures enable us to use the findings for future references. When personal inhalable air levels of cobalt, cobalt skin levels skin and biological monitoring of cobalt in blood were analysed, the skin exposure was determined to be import as a route of uptake. Skin exposure to cobalt in the hard metal industry, could further affect the total uptake in the same order of magnitude as air exposure. In vitro investigations of cobalt using the human keratinocyte cell line HaCaT, showed that CoCl2 triggered an alarm system in cells where the proinflammatory cytokines/chemokines IL-6, CXCL8 and CCL2, known to be involved in skin inflammation, were secreted in a time- and dosedependent manner. Comparing HaCaT cells of high- and low differentiation stages indicated that the effect of cobalt chloride on cell toxicity occurs throughout the living epidermis. CoCl2 exposure also resulted in secretion of the proinflammatory cytokines IL-1β and IL-18, and caspase-1, which indicates activation of the NLRP3 inflammasome in the cells. CoCl2 regulates the inflammasome both as primer and as an activator. Our mRNA results indicates a negative feedback mechanism in the inflamamsome due to the exposure. The inflammatory response in general is more dose than time dependent, which be important for understanding the mechanisms of allergic sensitization.
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| 2. |
- Linderholm, Linda, 1978-
(författare)
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Assessment of Environmental Pollutants in Humans from Four Continents : Exposure levels in Slovakia, Guinea-Bissau, Nicaragua and Bangladesh
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Humans are continuously exposed to complex mixtures of anthropogenic chemicals. This thesis focus on human exposure to persistent organic pollutants (POPs). POPs ability to bioaccumulate and biomagnify together with the extensive historical use of POPs in e.g. agriculture and industry have resulted in detection of these compounds in humans and animals from all over the world. Adverse health effects caused by POPs are of particular concern for newborns and young individuals. The objective of this thesis is to assess human exposure to a selected set of POPs and their metabolites. More specifically, one aim of my thesis is to determine the exposure to polychlorinated biphenyls (PCBs) and in particular their methylsulfonyl and hydroxylated metabolites in humans from a “hot-spot” area of PCB contamination in eastern Slovakia. The maternal transfer of these chemicals is studied. Further, another specific aim is to determine occurrence, levels and, when possible, temporal trends of POPs in children and adults from three developing countries, Nicaragua, Guinea-Bissau and Bangladesh. High concentrations of PCBs and their metabolites are shown in men and women from Michalovce in eastern Slovakia. Placental transfer of methylsulfonyl-metabolites of PCBs and 4,4’-DDE was observed for the first time. Decreasing temporal trends of the majority of POPs are shown in serum from a cohort of policemen from Guinea-Bissau. In contrast, the levels of polybrominated diphenyl ethers (PBDEs) show an increasing time trend. Within five years, decreasing levels of POPs were also shown in children working and living at a waste disposal site in Nicaragua. Children working and living at waste disposal sites in Bangladesh have considerably lower levels of POPs compared to the children from Nicaragua except for 4,4’-DDT and 4,4’-DDE that are present at very high concentrations, indicating ongoing use of technical DDT. There are many studies on levels and trends of environmental pollutants from the developed industrial countries in the world, whereas data from developing countries is still scarce. This thesis contributes to partly fill this data gap since it includes assessments of POPs in children and adults from four countries on four continents.
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| 3. |
- Segerstedt, Eugenia
(författare)
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Small town, big move : Constructions of place in transiting mining communities
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The dissertation accounts for construction of place in mining communities as they undergo a major urban transformation. In the 2010s, urban centres in the northern Sweden mining communities of Gällivare and Kiruna entered a new execution phase of a large-scale transformation precipitated by ground subsidence caused by mining activities, a transformation that continues. The ambition to make the transition socially sustainable and contribute to more attractive communities resulted in research projects focused on these aspects.The aim of this dissertation is to describe and analyse how place is constructed in established mining communities in transition through the following research questions: How is place constructed in dialogues on social sustainability and attractiveness? How do people of different age groups, professions and gender construct place in established mining communities in transition? What are the possibilities and limitations of different research methods in relation to including residents’ perspectives in the transformation process? The overall theoretical standpoint of this dissertation is that place is socially constructed: place is made by people discussing and describing it, by discourses that are produced, reproduced and challenged in social groups beyond individual standpoints. Residents’ thoughts and ideas about place are an important part of what the communities are, were and will become, along with their reflexive relationship with their place of residence and thoughts on their own and other peoples’ future in the respective communities (See Lefebvre, 1991, Halegua, 2020). By reflexive relationship with place I am referring to actions where residents consider risk, think about their future, define what makes their life more meaningful and reflect upon changes in their environment; local community is one of the levels of these thoughts, attitudes and feelings.Five studies were conducted to investigate construction of place in the transiting mining communities of Kiruna and Gällivare using mixed methods: participatory action research in Living Labs, statistical logistics regression analysis, GIS 3D visualisation. This included an analytical review of research on established mining communities, a 3D visualisation of social issues in Gällivare, an analysis of Living Labs with residents of Gällivare and Kiruna as well as a group of commuters to Gällivare, a comparative study of three co-creative processes in Kiruna and a statistical analysis of construction of place in Kiruna over time.The results show that residents, while participating in dialogues on social sustainability and attractiveness, construct the transient communities through contradictory storylines. Bearing themes in construction of place were aggregated through the storylines that residents constructed and reproduced, expressed different attitudes towards and referenced. The established storylines with a long history, such as model community, a town constructed as a new establishment planned to be modern and inclusive; nature and the town, the theme of beautiful natural surroundings valued by residents and visitors, including the mountains, forest, rivers and lakes; big city elsewhere, a big city used in the construction of Kiruna and Gällivare to show what those places are not, as a counterpoint; the secure small town, the storyline of knowing “everyone”, spontaneously meeting, helping each other, were all used to re-establish the sense of stability and reframe the new environment by connecting it to the construction of the communities’ past. The storyline, the conditionally inclusive town, was used to question the character of and conditions for inclusion in the local interconnected context. The storylines of hope of a more inclusive and sustainable future and broken promises of a faster transformation, resulting in bigger changes, were used to process the change to imagined futures of place.There were certain patterns in how people of different age groups, professions and gender construct place in transiting communities. The main difference in the way men and women constructed Gällivare, according to 3D visualisation analysis, was that women were less content than men with the built environment, following similar geographical patterns. Construction of Kiruna as a place to live (or leave) over time has shown that while blue-collar workers were less prone than white-collar workers to consider leaving in 2011, there were no significant differences between social classes in 2016 in that regard. Generational patterns were similar - the younger the respondent, the more prone he or she is to consider leaving - but the gap between the youngest respondents and all other respondents has grown. The effect of social bonds that inhibit the will to move went from insignificant to visible for men and from significant to stronger for women. The hope of a transformed Kiruna, so ubiquitous in 2011, was much less pronounced in 2016.Different research methods had different potential in terms of the potential to understand construction of place and were thus included in the planning process: the statistical method gave representative patterns of factors behind whether residents consider leaving and how the patterns changed over time, but this method was limited in its ability to generate an understanding of the contextual meaning of those patterns, Living Labs provided the opportunity to see how place is constructed in dialogues but was limited in its ability to generate an understanding of preferences and individual standpoints, 3D visualisation provided spatial patterns beyond statistics and means for discussion and communication of those patterns with a broad variety of actors but had limited potential for their interpretation.
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| 4. |
- Tödt, Kristina, 1966-
(författare)
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The relationship between physical function and experience of fatigue in patients with chronic obstructive pulmonary disease
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundChronic Obstructive Pulmonary Disease (COPD) is increasing throughout the world and most rapidly among women. COPD is characterized by a progressive loss of physical functions. The reason for this is multi-factorial and include not only lung related deficiencies but also several systemic consequences and symptoms of which several are potential restrictors of physical function. The relationship between physical function and symptoms are not clear, especially not among women with COPD.AimThe overall aim of this thesis was to illuminate the relationship between two dimensions of physical function (physical activity and physical capacity) and experience of fatigue. The specific aims were to explore factors associated with low physical activity and to examine experience of fatigue and its relationship to physical capacity and disease severity in men and women with COPD.MethodsA cross-sectional study was conducted including 121 patients (67 women) with stable COPD and mean age of 67 (+/-7) years. Physical activity was measured with the International Physical Activity Questionnaire short form. Physical capacity included assessment of lung function (dynamic spirometry), exercise capacity (the 6-minute walk distance [perceived dyspnoea and leg fatigue in connection to the test]) and muscle strength (the Timed Stands Test and grip strength). Fatigue was assessed with structured questions covering the frequency, duration and severity of fatigue the previous month and patients were categorized as those with no fatigue, moderate fatigue or severe fatigue. Data about other symptoms (dyspnoea, anxiety and depression), symptom burden (Memorial Symptom Assessment Scale), fat and fat free mass (bio-impedance analysis) and smoking history was collected.ResultsForty-two percent of the patients reported a low physical activity level. A majority of the patients reported experience of fatigue the previous month, 52% moderate fatigue and 25% severe fatigue. Low physical activity was associated with severe fatigue, worse exercise capacity and a higher amount of smoking. There were no differences in experience of fatigue between men and women. Men with fatigue had worse physical capacity and disease severity compared to men without fatigue. Women with fatigue had comparable physical capacity and disease severity to women without fatigue except for a higher perceived leg fatigue after the exercise capacity test. Multiple logistic regression analysis showed that exercise capacity and disease severity were associated with fatigue in both men and women but in women, leg fatigue was also strongly associated with the presence of fatigue.ConclusionsSevere fatigue, worse exercise capacity and a higher amount of smoking were independently associated with low PA. This result suggests that patients with severe fatigue might need specific strategies to become more physically active. Presence of fatigue was associated with exercise capacity and disease severity in both men and women. In addition, in women leg fatigue was strongly associated with fatigue. Muscle endurance training might be extra important in the rehabilitation of women with COPD experiencing fatigue. However the association between fatigue and exercised induced leg fatigue among the women warrant further investigation.
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