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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Polyfarmaci hos äldre :  – ett världsomfattande hälsoproblem / Polypharmacy in elderly  : – a worldwide healthproblem

Johansson, Jeanette, Särnbäck, Marie January 2010 (has links)
<p>Antalet äldre har ökat i hela världen och fortsätter att öka. I takt med stigande ålder ökar risken för sjukdomar och därmed även läkemedelsanvändningen. Personer över 80 år konsumerar i genomsnitt 5,8 läkemedel per person och äldre på sjukhem tio läkemedel per person vilket är en ökning med 60 % sedan slutet av 1980-talet. Anledningen till denna ökning är att det idag finns stora möjligheter att förebygga och behandla många sjukdomar eftersom det hela tiden utvecklas nya läkemedel och behandlingsmetoder. Polyfarmaci och olämplig förskrivning av läkemedel till äldre över 65 år enligt Beers kriterier (se bilaga I) är ett växande och världsomspännande hälsoproblem. Vid polyfarmaci används i genomsnitt fem eller flera olika läkemedel. Polyfarmaci ökar i takt med stigande ålder och är vanligast hos kvinnor samt hos lågutbildade individer. Med ökat antal läkemedel ökar också risken för biverkningar samt interaktioner eftersom äldre är känsligare på grund av åldersförändringar och sjukdom. Syftet med studien var att belysa förekomsten av polyfarmaci och olämplig förskrivning av läkemedel till äldre samt dess konsekvenser. Studien utfördes som en litteraturstudie där 17 vetenskapliga artiklar analyserades. Resultatet visar att en tredjedel av de äldre patienterna konsumerar olämpliga läkemedel, enligt Beers kriterier, vilket leder till onödigt lidande och ökad sjukhusvistelse. Det är därför viktigt att all vårdpersonal är väl insatta i de åldersförändringarna som sker hos den äldre individen samt har god kunskap inom farmakologi. Sjuksköterskor och läkare bör även förbättra samarbetet med farmaceuterna för att öka patientsäkerheten.</p><p> </p><p> </p> / <p>The elderly population is increasing all over the world. Aging is associated with diseases resulting in increased medical consumption. Elderly over 80 years consume in average 5,8 different drugs. Nursing home residents consume ten drugs which represents an increase of 60 % within the last two decades. This development is based on the increasing progress within the field medical treatment. Polypharmacy and inappropriate prescribing in elderly over 65 years, according to Beer´s criteria (annex I), results in a growing and worldwide health problem. Polypharmacy comprises use of multiple drugs (mostly five or more per day). Polypharmacy is associated with increased age and is most common in women and low educated individuals. Multiple medications increase the risk of adverse drug reactions and drug-drug interactions especially in old and frail persons with comorbidity. The aim of the study was to elucidate the prevalence and the consequences of polypharmacy and inappropriate prescribing in elderly. The study was based on a literature study in which 17 articles were analyzed. The result shows that one third of the elderly patients consume inappropriate medications, according to Beer´s criteria, which are associated with unnecessary suffering and increased hospital admission. It´s important that health care personnel gains understanding about the pharmacological consequences of body composition changes in older adults. Nurses and physicians should also improve their cooperation with pharmacists to increase knowledge leading to better patient safety.</p>
32

The Gene Repertoire of G protein-coupled Receptors : New Genes, Phylogeny, and Evolution

Bjarnadóttir, Þóra Kristín January 2006 (has links)
<p>The superfamily of G protein-coupled receptors (GPCRs) is one of the largest protein families of mammalian genomes and can be divided into five main families; <i>Glutamate</i>, <i>Rhodopsin</i>, <i>Adhesion</i>, <i>Frizzled</i>, and <i>Secretin</i>. GPCRs participate in most major physiological functions, contributing to the fact that they are important targets in drug discovery. In paper I we mined the human and mouse genomes for new <i>Adhesion</i> GPCR genes. We found two new human genes (GPR133 and GPR144) and 17 mouse <i>Adhesion</i> genes, bringing the number up to 33 human and 31 mouse genes. In paper II we describe 53 new splice variants for human <i>Adhesion</i> receptors supported by expressed sequence tags (EST) data. 29 of these variants seem to code for functional proteins, several of which lack one or more functional domains in the N-termini. Lack of certain domains is likely to affect ligand binding or interaction with other proteins. Paper III describes the <i>Glutamate</i> GPCR in human, mouse, <i>Fugu</i>, and zebrafish. We gathered a total of 22 human, 79 mouse, 30 <i>Fugu</i>, and 32 zebrafish sequences and grouped these into eight clans using phylogenetic methods. The report provides an overview of the expansion or deletions among the different branches of the <i>Glutamate</i> receptor family. Paper IV focuses on the trace amine (TA) clan of <i>Rhodopsin</i> GPCRs. We identified 18 new rodent genes, 57 zebrafish genes, and eight <i>Fugu</i> genes belonging to the clan. Chromosomal mapping together with phylogenetic relationships suggests that the family arose through several mechanisms involving tetraploidisation, block duplications, and local duplication events. Paper V provides a comprehensive dataset of the GPCR superfamily of human and mouse containing 495 mouse and 400 human non-olfactory GPCRs. Phylogenetic analyses showed that 329 of the receptors are found in one-to-one orthologous pairs, whereas other receptors may have originated from species-specific expansions.</p>
33

Neuropeptidomics – Methods and Applications

Sköld, Karl January 2006 (has links)
<p>The sequencing of genomes has caused a growing demand for functional analysis of gene products. This research field named proteomics is derived from the term proteome, which by analogy to genome is defined as all proteins expressed by a cell or a tissue. Proteomics is however methodologically restricted to the analysis of proteins with higher molecular weights. The development of a technology which includes peptides with low molecular weight and small proteins is needed, since peptides play a central role in many biological processes. </p><p>To study endogenous peptides and hormones, the peptidome, an improved method comprising rapid deactivation in combination with nano-flow liquid chromatography (LC) and mass spectrometry (MS) was developed. The method has been used to investigate endogenous peptides in brains of mouse and rat. Several novel peptides have been discovered together with known neuropeptides. </p><p>To elucidate the <i>post mortem</i> time influence on peptides and proteins, a time course study was performed using peptidomics and proteomics technologies. Already after three minutes a substantial amount of protein fragments emerged in the peptidomics study and some endogenous peptides were drastically reduced with increasing <i>post mortem</i> time. Of about 1500 proteins investigated, 53 were found to be significantly changed at 10 minutes <i>post mortem</i> as compared to control. Moreover, using western blot the level of MAPK phosphorylation was shown to decrease by 95% in the 10 minutes <i>post mortem </i>sample. </p><p>A database, SwePep (a repository of endogenous peptides, hormones and small proteins), was constructed to facilitate identification using MS. The database also contains additional information concerning the peptides such as physical properties. A method for analysis of LC-MS data, including scanning for, and further profiling of, biologically significant peptides was developed. We show that peptides present in different amounts in groups of samples can be automatically detected.</p><p>The peptidome approach was used to investigate levels of peptides in two animal models of Parkinson’s disease. PEP-19, was found to be significantly decreased in the striatum of MPTP lesioned parkinsonian mice. The localization and expression was further investigated by imaging MALDI MS and by <i>in situ</i> hybridization. The brain peptidome of reserpine treated mice was investigated and displayed a number of significantly altered peptides. This thesis demonstrates that the peptidomics approach allows for the study of complex biochemical processes.</p>
34

Development of New Methods for Inferring and Evaluating Phylogenetic Trees

Hill, Tobias January 2007 (has links)
<p>Inferring phylogeny is a difficult computational problem. Heuristics are necessary to minimize the time spent evaluating non optimal trees. In paper I, we developed an approach for heuristic searching, using a genetic algorithm. Genetic algorithms mimic the natural selections ability to solve complex problems. The algorithm can reduce the time required for weighted maximum parsimony phylogenetic inference using protein sequences, especially for data sets involving large number of taxa. </p><p>Evaluating and comparing the ability of phylogenetic methods to infer the correct topology is complex. In paper II, we developed software that determines the minimum subtree prune and regraft (SPR) distance between binary trees to ease the process. The minimum SPR distance can be used to measure the incongruence between trees inferred using different methods. Given a known topology the methods could be evaluated on their ability to infer the correct phylogeny given specific data. </p><p>The minimum SPR software the intermediate trees that separate two binary trees. In paper III we developed software that given a set of incongruent trees determines the median SPR consensus tree i.e. the tree that explains the trees with a minimum of SPR operations. We investigated the median SPR consensus tree and its possible interpretation as a species tree given a set of gene trees. We used a set of α-proteobacteria gene trees to test the ability of the algorithm to infer a species tree and compared it to previous studies. The results show that the algorithm can successfully reconstruct a species tree.</p><p>Expressed sequence tag (EST) data is important in determining intron-exon boundaries, single nucleotide polymorphism and the coding sequence of genes. In paper IV we aligned ESTs to the genome to evaluate the quality of EST data. The results show that many ESTs are contaminated by vector sequences and low quality regions. The reliability of EST data is largely determined by the clustering of the ESTs and the association of the clusters to the correct portion of genome. We investigate the performance of EST clustering using the genome as template compared to previously existing methods using pair-wise alignments. The results show that using the genome as guidance improves the resulting EST clusters in respect to the extent ESTs originating from the same transcriptional unit are separated into disjunct clusters. </p>
35

Neuropeptidomics – Methods and Applications

Sköld, Karl January 2006 (has links)
The sequencing of genomes has caused a growing demand for functional analysis of gene products. This research field named proteomics is derived from the term proteome, which by analogy to genome is defined as all proteins expressed by a cell or a tissue. Proteomics is however methodologically restricted to the analysis of proteins with higher molecular weights. The development of a technology which includes peptides with low molecular weight and small proteins is needed, since peptides play a central role in many biological processes. To study endogenous peptides and hormones, the peptidome, an improved method comprising rapid deactivation in combination with nano-flow liquid chromatography (LC) and mass spectrometry (MS) was developed. The method has been used to investigate endogenous peptides in brains of mouse and rat. Several novel peptides have been discovered together with known neuropeptides. To elucidate the post mortem time influence on peptides and proteins, a time course study was performed using peptidomics and proteomics technologies. Already after three minutes a substantial amount of protein fragments emerged in the peptidomics study and some endogenous peptides were drastically reduced with increasing post mortem time. Of about 1500 proteins investigated, 53 were found to be significantly changed at 10 minutes post mortem as compared to control. Moreover, using western blot the level of MAPK phosphorylation was shown to decrease by 95% in the 10 minutes post mortem sample. A database, SwePep (a repository of endogenous peptides, hormones and small proteins), was constructed to facilitate identification using MS. The database also contains additional information concerning the peptides such as physical properties. A method for analysis of LC-MS data, including scanning for, and further profiling of, biologically significant peptides was developed. We show that peptides present in different amounts in groups of samples can be automatically detected. The peptidome approach was used to investigate levels of peptides in two animal models of Parkinson’s disease. PEP-19, was found to be significantly decreased in the striatum of MPTP lesioned parkinsonian mice. The localization and expression was further investigated by imaging MALDI MS and by in situ hybridization. The brain peptidome of reserpine treated mice was investigated and displayed a number of significantly altered peptides. This thesis demonstrates that the peptidomics approach allows for the study of complex biochemical processes.
36

Development of New Methods for Inferring and Evaluating Phylogenetic Trees

Hill, Tobias January 2007 (has links)
Inferring phylogeny is a difficult computational problem. Heuristics are necessary to minimize the time spent evaluating non optimal trees. In paper I, we developed an approach for heuristic searching, using a genetic algorithm. Genetic algorithms mimic the natural selections ability to solve complex problems. The algorithm can reduce the time required for weighted maximum parsimony phylogenetic inference using protein sequences, especially for data sets involving large number of taxa. Evaluating and comparing the ability of phylogenetic methods to infer the correct topology is complex. In paper II, we developed software that determines the minimum subtree prune and regraft (SPR) distance between binary trees to ease the process. The minimum SPR distance can be used to measure the incongruence between trees inferred using different methods. Given a known topology the methods could be evaluated on their ability to infer the correct phylogeny given specific data. The minimum SPR software the intermediate trees that separate two binary trees. In paper III we developed software that given a set of incongruent trees determines the median SPR consensus tree i.e. the tree that explains the trees with a minimum of SPR operations. We investigated the median SPR consensus tree and its possible interpretation as a species tree given a set of gene trees. We used a set of α-proteobacteria gene trees to test the ability of the algorithm to infer a species tree and compared it to previous studies. The results show that the algorithm can successfully reconstruct a species tree. Expressed sequence tag (EST) data is important in determining intron-exon boundaries, single nucleotide polymorphism and the coding sequence of genes. In paper IV we aligned ESTs to the genome to evaluate the quality of EST data. The results show that many ESTs are contaminated by vector sequences and low quality regions. The reliability of EST data is largely determined by the clustering of the ESTs and the association of the clusters to the correct portion of genome. We investigate the performance of EST clustering using the genome as template compared to previously existing methods using pair-wise alignments. The results show that using the genome as guidance improves the resulting EST clusters in respect to the extent ESTs originating from the same transcriptional unit are separated into disjunct clusters.
37

The Gene Repertoire of G protein-coupled Receptors : New Genes, Phylogeny, and Evolution

Bjarnadóttir, Þóra Kristín January 2006 (has links)
The superfamily of G protein-coupled receptors (GPCRs) is one of the largest protein families of mammalian genomes and can be divided into five main families; Glutamate, Rhodopsin, Adhesion, Frizzled, and Secretin. GPCRs participate in most major physiological functions, contributing to the fact that they are important targets in drug discovery. In paper I we mined the human and mouse genomes for new Adhesion GPCR genes. We found two new human genes (GPR133 and GPR144) and 17 mouse Adhesion genes, bringing the number up to 33 human and 31 mouse genes. In paper II we describe 53 new splice variants for human Adhesion receptors supported by expressed sequence tags (EST) data. 29 of these variants seem to code for functional proteins, several of which lack one or more functional domains in the N-termini. Lack of certain domains is likely to affect ligand binding or interaction with other proteins. Paper III describes the Glutamate GPCR in human, mouse, Fugu, and zebrafish. We gathered a total of 22 human, 79 mouse, 30 Fugu, and 32 zebrafish sequences and grouped these into eight clans using phylogenetic methods. The report provides an overview of the expansion or deletions among the different branches of the Glutamate receptor family. Paper IV focuses on the trace amine (TA) clan of Rhodopsin GPCRs. We identified 18 new rodent genes, 57 zebrafish genes, and eight Fugu genes belonging to the clan. Chromosomal mapping together with phylogenetic relationships suggests that the family arose through several mechanisms involving tetraploidisation, block duplications, and local duplication events. Paper V provides a comprehensive dataset of the GPCR superfamily of human and mouse containing 495 mouse and 400 human non-olfactory GPCRs. Phylogenetic analyses showed that 329 of the receptors are found in one-to-one orthologous pairs, whereas other receptors may have originated from species-specific expansions.
38

Obesity and Increased Susceptibility : Role of FTO and MGAT1 Genetic Variants

Jacobsson, Josefin A January 2011 (has links)
Obesity is a complex and a highly individualized disease and the molecular mechanisms behind this disorder need to be better elucidated. Identification of genes and genetic variants that are involved provide opportunities to establish a genetic understanding of the disease. These findings may also provide more rational approaches to therapy, either by identifying underlying causes or point out the need for different treatments. In addition, the timing and severity of obesity may provide insights into the aetiology of obesity and also identify age-specific determinants of weight gain. Recently, genome-wide association studies have led to a rapid progress in our understanding of the genetic basis of various diseases and candidate genes for obesity have been identified. The overall aim of this thesis was to investigate the genetic impact on severity of childhood obesity and the associations between obesity and genetic variants in the fat mass and obesity associated gene, FTO, and MGAT1, the gene encoding mannosyl (α-1,3-)-glycoprotein β-1,2-N-acetyl-glucosaminyltransferase. We show that the impact of parental body mass index (BMI) on the severity of obesity in children is strengthened as the child grows older, whereas the age at obesity onset is of limited importance. By association studies, we show that single nucleotide polymorphisms downstream MGAT1 influence susceptibility to obesity. Moreover, these variants affect the levels of unsaturated fatty acids and desaturase indices, variables previously shown to correlate with obesity. Furthermore, one variant in the first intronic region of FTO is associated with obesity among children but not with BMI or other measures of adiposity at older ages. However, this variant shows a weight-dependent association with cognitive function among elderly men. By direct sequencing, we identified novel variants in FTO, affecting glucose homeostasis in a BMI-independent manner. Furthermore, we found gender specific effects for FTO, both regarding obesity susceptibility and related phenotypes.
39

Controlled release gel formulations for mucosal drug delivery /

Paulsson, Mattias, January 2001 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 6 uppsatser.
40

Refined in vitro models for prediction of intestinal drug transport : role of pH and extracellular additives in the caco-2 cell model /

Neuhoff, Sibylle, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.

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