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- Pettersson, Hans, 1980-
(author)
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Risk of hearing loss from combined exposure to hand-arm vibrations and noise
- 2013
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Doctoral thesis (other academic/artistic)abstract
- Hearing loss from noise exposure is one of the most common occupational injuries, and exposure to vibrations may increase the risk of noise-induced hearing loss. Earlier cross-sectional and longitudinal studies found an increased risk of noise-induced hearing loss among workers with vibration-induced white fingers (VWF) symptoms compared to workers without such symptoms. It has been suggested that vibrations to the hand stimulate the sympathetic nervous system and cause vasoconstriction in both the exposed hand and the ears and that this contributes to noise-induced hearing loss. The overall aim of this thesis was to examine how hand-arm vibrations (HAV) interact with noise in the development of noise-induced hearing loss.The experimental study in this thesis examined the effects of HAV and noise, both separately and combined, on the temporary threshold shift (TTS) in hearing in 22 healthy male and female subjects. The two longitudinal studies in this thesis were based on a cohort of 189 male workers at a heavy engineering workshop. The first cohort study examined the risk of noise-induced hearing loss from long-term exposure to HAV and noise. The second cohort study examined if workers with VWF had an increased risk of noise-induced hearing loss compared to workers without such symptoms. Finally, the questionnaire study in this thesis examined the occurrence of Raynaud’s phenomenon among 133 men and women with noise-induced hearing loss in relation to exposure to vibrations.In the experimental study, no differences in TTS in hearing were observed after combined exposure to HAV and noise compared to exposure to only noise. In the first cohort study, there was an increased risk of noise-induced hearing loss with increased exposure to HAV in a noisy environment. In the second cohort study, it was found that workers with VWF had an increased risk of noise-induced hearing loss compared to workers without VWF. In the questionnaire study, many men and women with noise-induced hearing loss had used hand-held vibrating machines suggesting that vibrations might contribute to noise-induced hearing loss. A high prevalence of Raynaud’s phenomenon was found among men.This thesis demonstrated that there was a long-term effect on noise-induced hearing loss from combined exposure to noise and HAV, but no short-term effect, and that having Raynaud’s phenomenon may also increase the risk of noise-induced hearing loss.
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- Fornander, Elin, 1981-
(author)
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Consuming and communicating identities : Dietary diversity and interaction in Middle Neolithic Sweden
- 2011
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Doctoral thesis (other academic/artistic)abstract
- Isotope analyses on human and faunal skeletal remains from different Swedish Neolithic archaeological contexts are here applied as a means to reconstruct dietary strategies and mobility patterns. The chronological emphasis is on the Middle Neolithic period, and radiocarbon dating constitutes another central focus. The results reveal a food cultural diversity throughout the period in question, where dietary differences in part correspond to, but also transcend, the traditionally defined archaeological cultures in the Swedish Early to Middle Neolithic. Further, these differences, and the apparent continued utilisation of marine resources in several regions and cultural contexts, can only in part be explained by chronology or availability of resources depending on geographic location. Thus, the sometimes suggested sharp economic shift towards an agricultural way of life at the onset of the Neolithic is refuted. Taking the potential of isotope analyses a step further, aspects of Neolithic social relations and identities are discussed, partly from a food cultural perspective embarking from the obtained results. Relations between people and places, as well as to the past, are discussed. The apparent tenacity in the dietary strategies observed is understood in terms of their rootedness in the practices and social memory of the Neolithic societies in question. Food cultural practices are further argued to have given rise to different notions of identity, some of which can be related to the different archaeological cultures, although these cultures are not to be perceived as bounded entities or the sole basis of self-conceptualisation. Some of these identities have been focused around the dietary strategies of everyday life, whereas others emanate from practices, e.g. of ritualised character, whose dietary importance has been more marginal. Isotope analyses, when combined with other archaeological indices, have the potential to elucidate both these food cultural aspects.
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3. |
- Jacobsen, Kristin, 1982-
(author)
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Processing of the APP family by the α-secretases ADAM10 and TACE
- 2010
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Licentiate thesis (other academic/artistic)abstract
- Alzheimer’s disease (AD) is a progressive neurodegenerative disease, which is characterized by formation of amyloid plaques in the brain. The major constituent of these plaques is the hydrophobic peptide Aβ. Aβ accumulation is considered to be the main cause of the pathology seen in AD brains. Aβ is produced through sequential cleavage of the amyloid precursor protein (APP). APP can be processed by two different enzymatic pathways. Formation of Aβ requires cleavage of APP by β- and γ-secretase. However, most proteolytic processing of APP does not result in Aβ formation. Instead, APP is mainly cleaved by α-secretase, which not only precludes formation of the toxic Aβ peptide but also generates the neuroprotective sAPPα fragment. Increasing the α-secretase processing of APP is thereby a potential therapeutic strategy for AD. APP is a member of a conserved gene family, also including the APP-like proteins-1 and -2 (APLP1 and APLP2). The APP family members have essential and overlapping functions and have been reported to be processed in a similar way by the same enzymes. The processing of all APP family members is increased in response to several stimuli, including retinoic acid (RA) and insulin-like growth factor-1 (IGF-1), which also induce a shift towards α-secretase processing. The aim of this thesis was to investigate the mechanisms and signaling involved in induced α-secretase processing of the APP family. The main α-secretase candidates are ADAM10 and TACE. In this thesis we wanted to study the effects on expression levels of ADAM10 and TACE during RA treatment. We also wanted to investigate the mechanism behind IGF-1-induced processing of APP and APLP2. We found that both ADAM10 and TACE are up-regulated in response to RA, but that the signaling pathways involved differed between the two enzymes. Similarly, we showed that IGF-1-induced processing of APLP2, but not of APP, is dependent on PKC. Furthermore, we showed that ADAM10 is the main α-secretase for APP, whereas TACE cleaves APLP2 in response to IGF-1. We conclude that although APP and APLP2 proteolytic processing are induced by the same stimuli, the processing is dependent on different signaling pathways and processing enzymes, which in turn are differentially regulated.
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- Wätterbjörk, Inger, 1955-
(author)
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Couples' experiences of an extended information visit about prenatal screening : decision making and satisfaction
- 2014
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Doctoral thesis (other academic/artistic)abstract
- The overall aim of this thesis was to describe pregnant women's and partners' views and experiences on early prenatal screening with the combined test, with special focus on the two-step information model.Interviews were performed with 15 couples who had taken part in the extended information visit about prenatal screening, describing their perceptions of the information model (I) and ten couples or women of those, for a follow-up interview exploring their decision-making process (II). Seven couples, who had not taken part in the extended information visit, were interviewed describing their views and experiences about prenatal screening (III). A questionnaire was answered by 295 women and by 223 partners about their satisfaction about the decision whether or not to participate in the combined test, and their assessment of whether or not this choice had been difficult (IV).The results showed that different opinions were expressed about the offer of the extended information visit. The separate visit was welcomed by most couples (I). The decision-making process regarding whether to take part in the test or not was described by most couples as a fairly straightforward decision, while for others it was a more complex process that required a great deal of consideration (II). An apprehension of the test, by some of those who had refrained the extended information visit, was that it was an expression of society's involvement in decisions that belong to the expectant parents (III). Ninety-three percent of both women and partners considered the decision about participating in the combined tests as uncomplicated, and well over 90%, of both women and partners were satisfied with their decision (IV).The conclusions in this thesis, are that the decision whether or not to participate in the combined test is multidimensional and influenced by different views. The two-step information model helped the pregnant woman and the partner to make a decision in a fairly straightforward process or a more complex process with mixed feelings.
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