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- Andersson, Lars-Magnus, 1968
(author)
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On cerebrospinal fluid markers of HIV-1 infection
- 2003
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Doctoral thesis (other academic/artistic)abstract
- HIV-1 infects the central nervous system early in the course of infection and neurological complications are common in HIV-1-infected individuals. Approximately 20% of individuals with acquired immunodeficiency syndrome (AIDS) not treated with antiretroviral therapy develop a subcortical dementia, AIDS dementia complex (ADC). The pathological pathways that lead to nerve cell injury in HIV-1 infection are not fully understood. Antiretroviral therapy has lowered the incidence of opportunistic infections and tumours in HIV-1 infection but the impact on ADC is less clear.The ganglioside GD3 (GD3) is expressed by activated microglia and reactive astroglia in the adult brain. Glial fibrillary acidic protein (GFAp) is an astrocyte marker. We have analysed cerebrospinal fluid (CSF) levels of GD3 and GFAp in 22 neuroasymptomatic HIV-1 infected individuals and 44 age-matched HIV-negative controls. The mean CSF GD3 level was higher in HIV-1 infected individuals than in controls. Six HIV-1-infected individuals had elevated CSF GD3 concentrations but normal GFAp levels indicating microglial activation early in the course of infection in some patients.To study a marker of axonal degeneration in HIV-1 infection, we measured CSF protein tau (tau) in 37 neuroasymtomatic HIV-1 infected individuals, 8 patients with ADC, 7 HIV-1 infected patients with other CNS opportunistic infections or tumours, and 42 age-matched HIV-negative controls. CSF tau levels were elevated in patients with ADC and other CNS opportunistic infections or tumours compared to neuroasymptomatic HIV-1 infected individuals and controls. CSF tau might be used as a marker of axonal degeneration but it cannot discriminate between ADC and other CNS opportunistic infections or tumours in HIV-1 infection.HIV-1 infection of the CNS triggers a cellular immune response that can be measured as elevated CSF neopterin concentrations and disruption of the blood-brain barrier is a common finding in HIV-1 infection. To investigate the relationship between intrathecal immune activation and disruption of the blood-brain barrier, we analysed CSF and serum neopterin, CSF and plasma HIV-1 RNA, CSF mononuclear cell count, and albumin ratio in 110 neuroasymptomatic HIV-1-infected individuals without antiretroviral treatment. The albumin ratio was correlated to the CSF and serum neopterin concentrations and to the CSF HIV-1 RNA levels but not to the plasma HIV-1 RNA levels, indicating that cellular immune activation, and possibly, intrathecal HIV-1 virus replication, are factors associated with increased blood-brain barrier permeability in neuroasymptomatic HIV-1-infected individuals.HIV-1 can be isolated from blood from almost all HIV-1-infected individuals not treated with antiretroviral therapy. Isolation rates from CSF, however, are considerably lower, ranging from 20 to 70%. We examined 303 CSF samples and 278 paired blood samples from 157 HIV-1 seropositive patients in all stages of the disease to evaluate HIV-1 RNA levels in CSF and blood as a predictor of culturability and to estimate a cut-off level above which the positive predictive value for positive virus isolation was =90%. While HIV-1 was isolated from the vast majority of blood samples with HIV-1 RNA levels just above the detection limit of the assay (>200 copies/mL), a cut-off level of >5000 HIV-1 RNA copies/mL was required to yield a positive predictive value =90% for virus isolation from CSF samples.
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| 2. |
- Andersson, Magnus
(author)
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Hemmet och världen. Rumsliga perspektiv på medieanvändning
- 2006
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Doctoral thesis (other academic/artistic)abstract
- I Hemmet och världen studeras de rumsliga aspekterna av mediernas närvaro i människors vardagsliv. Med geografisk utgångspunkt i hemmet och världen argumenteras för att meideanvändningen är en rumslig praktik i flera bemärkelser. För det första används medier för att markera och manifestera hemmet; medier som hemmets väggar. För det andra överbryggar medier avstånd och skapar förbindelser med omvärlden; medier som hemmets vägar. För det tredje skapar medieanvändningen förutsättningar för en global kontext och referensram åt hemmet, åt den lokala tillvaron - och åt medieanvändningen själv. Detta gör medier till ett centralt verktyg för att reglera livsvärldens horisonter.
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| 3. |
- Andersson, Magnus, 1975
(author)
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Omvälvningarnas tid: Handelshuset Ekman i Göteborg på en europeisk kreditmarknad 1790–1820
- 2011
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Doctoral thesis (other academic/artistic)abstract
- The purpose of this doctoral dissertation is to chart and analyze the flow of payments and credits to and from Gothenburg for the period 1790−1820, with a special interest in the transactions involving The Merchant House Ekman & Co. Both bills of exchange transactions within Ekman & Co and protested bills of exchange for other firms are studied. Markus A. Denzel’s model of Cashless Payment is an instrument to study how bills of exchange were used to ease payments and credit relations in the European Early Modern Credit market between 1790 and 1820. European trade possibilities for the period 1790−1820 are discussed in chapter III. The period under scrutiny was rather dramatic with economic and political changes. In Great Britain there was the industrial revolution and France experienced the great political revolution, followed by the Napoleonic wars. Chapter IV explores the credit- and bill of exchange markets. Since protested bills of exchange and different ways to deal with the problems that occur are important, this dissertation examines protested bills of exchange for two periods 1798−1800 and 1811−1812. The reasons for protesting bills of exchange are either lack of acceptance or lack of payment, both of which are common in this analysis. As a consequence there were no more endorsement possibilities. Chapter V describes the business of The Merchant House Ekman for the period 1790−1800, with special interest in the bills of exchange transactions. Peter III Ekman started his business ca 1760. He realized the importance of European contacts and from early on he traded with Merchants in Amsterdam, Hamburg, Greifswald, Wolgast and Stralsund. During the period 1790−1800 he was one of the most important producers of salted herring in Gothenburg. As a return good he imported grain from Merchant houses in the Baltic Sea. He imported the important salt by using his own ships. Ekman’s credit transactions in the form of bills of exchange contracts are of central importance, but the difficulty with the bills of exchange transactions is that there are no obvious connections with the commodity transactions. Because of endorsement, it is impossible to tell exactly what bill of exchange belonged to a certain amount of traded commodity. Chapter VI examines the Ekman & Co shift from mostly trading in herring and iron to concentrate on colonial trade at the time of war. Concerning credit relations, a database has been created for bills of exchange dating from 1810, which is then used to analyze the credit relations that Ekman & Co had with other firms in the European market. The dissertation shows the benefits of discounting and how the endorsements were used, as well as the fact that the Cashless Payments system with the bills of exchange transactions worked. When the system failed there was an effective law that solved the problem. All of this is further evidence that Gothenburg was an integrated part of the European financial system.
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