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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

Närståendes behov av stöd då de vårdar eller stödjer en person med långvarig psykisk sjukdom / Relatives need of support when caring for or supporting a person suffering from mental illness

Ax Hansson, Anna, Derdziak, Anna January 2016 (has links)
Aim: To illuminate relatives need of support when caring for or supporting a person suffering from mental illness Background: Relatives of a person suffering from mental illness have different needs. It has for the past few years merely been little improvements in the relative's situation. Methods: Focus group interviews with fourteen relatives. Data were analyzed through manifest content analysis. Findings: Three categories were found: Functioning contact channels to the psychiatric health care organization, Need of an active support from the psychiatric health care organization and Need of support from community resources. Conclusion: The relatives need more attention and understanding for their situation. The support of relatives must be designed and monitored individually. A collaboration or a well-functioning relation with the psychiatric nurses, other professionals working in the health care organisation and social services gives a mutual respect and trust which in turn leads to that the relative is confirmed as an important resource in the care of the mentally ill person. The relatives need an increased support and understanding from the community.
32

Exploring next-generation sequencing in chronic lymphocytic leukemia

Ljungström, Viktor January 2016 (has links)
Next-generation sequencing (NGS) techniques have led to major breakthroughs in the characterization of the chronic lymphocytic leukemia (CLL) genome with discovery of recurrent mutations of potential prognostic and/or predictive relevance. However, before NGS can be introduced into clinical practice, the precision of the techniques needs to be studied in better detail. Furthermore, much remains unknown about the genetic mechanisms leading to aggressive disease and resistance to treatment. Hence, in Paper I, the technical performance of a targeted deep sequencing panel including 9 genes was evaluated in 188 CLL patients. We were able to validate 143/155 (92%) selected mutations through Sanger sequencing and 77/82 mutations were concordant in a second targeted sequencing run, indicating that the technique can be introduced in clinical practice. In Paper II we screened 18 NF-κB pathway genes in 315 CLL patients through targeted deep sequencing which revealed a recurrent 4 base-pair deletion in the NFKBIE gene. Screening of NFKBIE in 377 additional cases identified the mutation in ~6% of all CLL patients. We demonstrate that the lesion lead to aberrant NF-κB signaling through impaired interaction with p65 and is associated with unfavorable clinical outcome. In Paper III we sought to delineate the genetic lesions that leads to relapse after fludarabine, cyclophosphamide, and rituximab treatment. Through whole-exome sequencing of pre-treatment and relapse samples from 41 cases we found evidence of frequent selection of subclones harboring driver mutations and subsequent clonal evolution following treatment. We also detected mutations in the ribosomal protein RPS15 in 8 cases (19.5%) and characterization of the mutations through functional assays point to impaired p53 regulation in cells with mutated RPS15. Paper IV aimed at characterizing 70 patients assigned to three major subsets (#1, #2, and #4) through whole-genome sequencing. Besides recurrent exonic driver mutations, we report non-coding regions significantly enriched for mutations in subset #1 and #2 that may facilitate future molecular studies. Collectively, this thesis supports the potential of targeted sequencing for mutational screening of CLL in clinical practice, provides novel insight into the pathobiology of aggressive CLL, and demonstrates the clinical outcome and cellular effects of NFKBIE and RPS15 mutations.
33

The prediction of HLA genotypes from next generation sequencing and genome scan data

Farrell, John J. 22 January 2016 (has links)
Genome-wide association studies have very successfully found highly significant disease associations with single nucleotide polymorphisms (SNP) in the Major Histocompatibility Complex for adverse drug reactions, autoimmune diseases and infectious diseases. However, the extensive linkage disequilibrium in the region has made it difficult to unravel the HLA alleles underlying these diseases. Here I present two methods to comprehensively predict 4-digit HLA types from the two types of experimental genome data widely available. The Virtual SNP Imputation approach was developed for genome scan data and demonstrated a high precision and recall (96% and 97% respectively) for the prediction of HLA genotypes. A reanalysis of 6 genome-wide association studies using the HLA imputation method identified 18 significant HLA allele associations for 6 autoimmune diseases: 2 in ankylosing spondylitis, 2 in autoimmune thyroid disease, 2 in Crohn's disease, 3 in multiple sclerosis, 2 in psoriasis and 7 in rheumatoid arthritis. The EPIGEN consortium also used the Virtual SNP Imputation approach to detect a novel association of HLA-A*31:01 with adverse reactions to carbamazepine. For the prediction of HLA genotypes from next generation sequencing data, I developed a novel approach using a naïve Bayes algorithm called HLA-Genotyper. The validation results covered whole genome, whole exome and RNA-Seq experimental designs in the European and Yoruba population samples available from the 1000 Genomes Project. The RNA-Seq data gave the best results with an overall precision and recall near 0.99 for Europeans and 0.98 for the Yoruba population. I then successfully used the method on targeted sequencing data to detect significant associations of idiopathic membranous nephropathy with HLA-DRB1*03:01 and HLA-DQA1*05:01 using the 1000 Genomes European subjects as controls. Using the results reported here, researchers may now readily unravel the association of HLA alleles with many diseases from genome scans and next generation sequencing experiments without the expensive and laborious HLA typing of thousands of subjects. Both algorithms enable the analysis of diverse populations to help researchers pinpoint HLA loci with biological roles in infection, inflammation, autoimmunity, aging, mental illness and adverse drug reactions.
34

Multiple displacement amplification and whole genome sequencing for the diagnosis of infectious diseases

Anscombe, C. J. January 2016 (has links)
Next-generation sequencing technologies are revolutionising our ability to characterise and investigate infectious diseases. Utilising the power of high throughput sequencing, this study reports, the development of a sensitive, non-PCR based, unbiased amplification method, which allows the rapid and accurate sequencing of multiple microbial pathogens directly from clinical samples. The method employs Φ29 DNA polymerase, a highly efficient enzyme able to produce strand displacement during the polymerisation process with high fidelity. Problems with DNA secondary structure were overcome and the method optimised to produce sufficient DNA to sequence from a single bacterial cell in two hours. Evidence was also found that the enzyme requires at least six bases of single stranded DNA to initiate replication, and is not capable of amplification from nicks. Φ29 multiple displacement amplification was shown to be suitable for a range of GC contents and bacterial cell wall types as well as for viral pathogens. The method was shown to be able to provide relative quantification of mixed cells, and a method for quantification of viruses using a known standard was developed. To complement the novel molecular biology workflow, a data analysis pipeline was developed to allow pathogen identification and characterisation without prior knowledge of input. The use of de novo assemblies for annotation was shown to be equivalent to the use of polished reference genomes. Single cell Φ29 MDA samples had better assembly and annotation than non-amplification controls, a novel finding which, when combined with the very long DNA fragments produced, has interesting implications for a variety of analytical procedures. A sampling process was developed to allow isolation and amplification of pathogens directly from clinical samples, with good concordance shown between this method and traditional testing. The process was tested on a variety of modelled and real clinical samples showing good application to sterile site infections, particularly bacteraemia models. Within these samples multiple bacterial, viral and parasitic pathogens were identified, showing good application across multiple infection types. Emerging pathogens were identified including Onchocerca volvulus within a CSF sample, and Sneathia sanguinegens within an STI sample. Use of Φ29 MDA allows rapid and accurate amplification of whole pathogen genomes. When this is coupled with the sample processing developed here it is possible to detect the presence of pathogens in sterile sites with a sensitivity of a single genome copy.
35

Avaliação dos mecanismos adquiridos de resistência a antimicrobianos em enterobactérias produtoras de carbapenemases por sequenciamento de nova geração

Nodari, Carolina Silva January 2016 (has links)
O objetivo deste trabalho foi caracterizar os mecanismos adquiridos de resistência de isolados de enterobactérias produtoras de carbapenemases utilizando a tecnologia de sequenciamento de nova geração. Foram incluídos no estudo quatro isolados – três Escherichia coli e uma Serratia marcescens – produtores de diferentes carbapenemases – OXA-370, KPC-2, NDM-1 e GES-5, respectivamente, obtidos a partir de um estudo de vigilância para detecção de carbapenemases. O DNA total dos isolados foi extraído utilizando kits comerciais e submetido à fragmentação enzimática para a obtenção de bibliotecas genômicas de aproximadamente 300 pares de bases. Após a preparação das bibliotecas, elas foram carregadas em chips 316 v2 para a plataforma Ion Torrent PGM e submetidas ao sequenciamento, utilizando um programa de 850 flows. Para cada genoma, foram obtidos aproximadamente um milhão de reads, os quais foram submetidos ao processo de montagem para a obtenção de genomas de aproximadamente 5Mb com uma cobertura de, em média, 175 vezes. As sequências obtidas foram submetidas à anotação utilizando o sistema RAST e a ferramenta online ResFinder. Sequências de inserção foram pesquisadas utilizando a ferramenta ISFinder. Além das carbapenemases, genes que codificam para outras β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) foram encontrados em todos os genomas. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic), bem como genes que codificam resistência às sulfonamidas e ao trimetoprim também foram comuns aos isolados avaliados. Os seguintes ambientes genéticos foram observados: blaOXA-370 é flanqueada pela IS5075-like, blaKPC-2 está inserida no transposon Tn4401, e blaNDM-1, no transposon Tn3000. Cada isolado de E. coli pertenceu a um sequence type (ST) distinto: 1099F pertence à ST617, 1326F, à ST648, e 2610F, à ST707. Nossos resultados indicaram a diversidade de genes de resistência que podem ser encontrados em um isolado clínico, ressaltaram a variedade de contextos genéticos em que as carbapenemases podem estar inseridas e demonstraram que o sequenciamento de nova geração pode ser utilizado como uma ferramenta para a caracterização de isolados bacterianos multirresistentes, auxiliando, entre outros aspectos, na tipagem e na identificação de determinantes de resistência. / The aim of this study was to characterize the resistome of carbapenemase-producing Enterobacteriaceae using a next-generation sequencing platform. Four isolates were included in this study – three Escherichia coli and one Serratia marcescens – producing different carbapenemases – OXA-370, KPC-2, NDM-1 and GES-5, respectively, obtained from a surveillance study for carbapenemase detection. Total DNA was extracted using commercially available kits and submitted to enzymatic fragmentation to obtain libraries of around 300 base pairs of each isolate. After library preparation, they were loaded in 316 v2 chips for Ion Torrent PGM platform, and sequencing was performed using an 850 flows program. For each genome, approximately a million reads were obtained, and they were further assembled. The genome length for each isolate was of around 5Mb, with a mean coverage of 175x. The RAST system and the online tool ResFinder were used for annotation, as well as ISFinder. Besides the carbapenemases, genes encoding for other β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) were found in all genomes. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic) were also detected in every isolate included in the study, as well as genes encoding for resistance determinants to sulfonamides and trimetoprim. The genetic environment of the carbapenemases was very similar to other isolates described in the literature – blaOXA-370 is flanked by IS5075-like, blaKPC-2 is inserted in transposon Tn4401, and blaNDM-1 was found in transposon Tn3000. Each isolate belonged to a distinct ST – 1099F is part of ST617, 1326F belonged to ST648 and 2610F, to ST707. Our results demonstrated the diversity of resistance determinants that can be found in a clinical isolate, highlighted the variability of genetic environments in which carbapenemases can be present and demonstrated that next-generation sequencing is a valuable tool for the characterization of multidrug-resistant isolates, and can provide information regarding the molecular typing and the identification of resistance determinants.
36

Engaging the Next-Gen Research Workforce

Knoell, Daren, Nizet, Victor, Rosemond, Erica, Hagemeier, Nicholas E. 23 February 2019 (has links)
The 2019 Research Symposium will bring together leaders in research and training from colleges and schools of pharmacy to discuss opportunities and challenges in research training at pharmacy schools. Symposium topics will include engaging pharmacy students in research projects and strengthening the pipeline for pharmacy research, integrating basic and clinical sciences in pharmacy schools, the value of research experience for building professional competencies and more. Through a mix of presentations, panel discussion and open forums, symposium participants will share experience and ideas and seek to identify points of potential collaboration to advance pharmacy research training. Deans, department chairs and faculty involved or interested in expanding research training are encouraged to attend.
37

Computational strategies to investigate the genetic cause of human eye disease

Goar, Wesley Andrew 01 May 2019 (has links)
It is estimated that 4000 genetic diseases/syndromes affect humans with one third of these diseases involving the eye. Many eye disorders, such as age-related macular degeneration that affects an estimated 170 million elderly adults worldwide, are associated with genetic variants. Since the conception of the human genome project we have learned a great deal about the genetic make-up of the human race and have identified over ~20,000 genes. Over 270 of these genes have been implicated in retinal diseases alone with many more genes involved in other forms of ocular disease. Though we have made a great deal of progress in understanding the genetics of eye disease, there remain many eye diseases with significant evidence of genetic components for which a disease-causing gene has not been identified. In my thesis research, I utilized computational tools and strategies to analyze microarrays and whole-exome sequencing to investigate the genetic causes of three different eye diseases. First, I utilized a combination of familial analyses and whole-exome sequencing to study the genetic cause of Keratoconus, a progressive cornea abnormality that can lead to distorted vision and light sensitivity. Second, I analyzed three different cohorts of patients with Bardet-Biedl syndrome (BBS), a syndromic retinopathy leading to blindness, using whole-exome sequencing to identify both known and novel genetic causes of BBS. Finally, I performed the largest whole-exome sequencing study at the time for Pigment Dispersion Syndrome (PDS), a disorder associated with glaucoma, and identified variants within previously established candidate genes and a novel candidate gene that is now the subject of further scientific investigation. By using computational tools and strategies in tandem with high-quality bench research performed by fellow lab members, we have identified both candidate and known eye disease-causing genes/mutations and furthered the goal to cure blindness.
38

Next generation monoclonal antibodies and their mechanisms of action against B-cell lymphomas

Peri, Delila 01 July 2012 (has links)
Next generation monoclonal antibodies (mAbs) are unique in that they are specifically designed to enhance their mechanisms of action, primarily complement fixation and antibody-dependent cellular cytotoxicity (ADCC). Recent studies suggest that complement-fixing properties of a mAb can counter its ability to activate NK cells and mediate ADCC. GA101, a third generation (type II anti-CD20) mAb, and rituximab-MAGE (glyco-engineered type I mAb) show enhanced ADCC and direct cell killing; while ofatumumab, a second generation anti-CD20 mAb, shows enhanced complement-mediated cytotoxicity (CMC). These studies set out to determine the primary mechanisms of actions of these various mAbs, and compare the effect of complement on their ability to activate NK cells and mediate ADCC or CMC. We also studied the efficiency of rituximab vs. rituximab-MAGE to deplete B-cells in vivo in mice expressing human transgenic CD20. In vitro, rituximab and ofatumumab fixed more complement and mediated a greater degree of CMC, than GA101 and rituximab-MAGE. Additionally, complement inhibited the ability of both rituximab and ofatumumab to bind to and activate NK cells, whereas, addition of complement to GA101 or rituximab-MAGE did not affect their NK cell activating ability. Complement also blocked rituximab-induced NK-cell mediated ADCC, but not GA101-induced NK-cell mediated ADCC. Finally, GA101 and rituximab-MAGE depleted a higher percentage of B cells in whole blood compared to rituximab and ofatumumab, whereas rituximab-MAGE depleted fewer B cells, in vivo, in a complement-dependent fashion. We conclude from these studies that there are significant differences among these antibodies and that the ability of a given antibody to mediate CMC and complement fixation correlates with the ability of complement to block the interaction between the antibody and NK cells.
39

Transcriptomics in the study of pathogens and human malignancies

January 2017 (has links)
acase@tulane.edu / Next generation sequencing (NGS) is a relatively new technology that has revolutionized the way scientists discover and investigate pathogens. It has been estimated that a staggering one in every five cancers worldwide is linked to an infectious agent. An understanding of the pathogen biology as well as the interactions with the host will lead to better therapies and outcomes for patients suffering from pathogen-associated malignancies. Despite the promise for this phenomenon through NGS-based approaches, we are still in the infancy of sequence analysis and are unable to fully appreciate the potential of NGS. To facilitate data mining, an automated computational pipeline for the simultaneous analysis of pathogen and host transcripts called RNA CoMPASS was developed. Using RNA CoMPASS to investigate a variety of sequencing datasets over the years, substantial bacterial contamination have been routinely identified in human-derived RNA-seq datasets that likely arose from environmental sources. Based on this analysis, a need for more stringent sequencing and analysis protocols to investigate sequence-based microbial signatures in clinical samples is crucial. NGS-based approaches were utilized to investigate the role of Epstein-Barr virus (EBV) in the pathogenesis of gastric carcinoma. A comprehensive assessment of the virome of various brain tissue samples was also performed, with the notion that an NGS-based detection method would be unbiased, sensitive, specific, and accurate. Taken together, these studies provide a framework for using NGS technology to study oncogenic pathogens and bring awareness to contamination issues within sequencing datasets. / 1 / Michael J Strong
40

Expressão de genes envolvidos no comportamento social em abelhas que apresentam diferentes níveis de eussocialidade / Expression of genes involved in the social behaviour of bees with different levels of eusociality

Araujo, Natália de Souza 05 July 2017 (has links)
O comportamento social pode ser descrito como qualquer atividade de interação intraespecífica incluindo a escolha entre parceiros reprodutivos, reconhecimento da espécie, comportamento altruísta e organização da sociedade animal. Entre as espécies de animais mais sintonizadas com seu ambiente social estão os insetos que, como por exemplo nas espécies de abelhas das tribos Apini e Meliponini, apresentam um padrão complexo de socialidade conhecido como comportamento altamente eussocial. As abelhas constituem um grupo ideal para o estudo das bases da evolução deste comportamento, pois apresentam uma grande diversidade de organização social, desde espécies solitárias até altamente eussociais. Embora a evolução da eussocialidade tenha sido motivo de muitos estudos, as mudanças genéticas envolvidas nesse processo não são completamente conhecidas. Dados da literatura fornecem um ponto de partida para o entendimento da relação entre alterações gênicas específicas e a eussocialidade, mas questões fundamentais na evolução do comportamento social ainda precisam ser respondidas. Recentemente, novas tecnologias de sequenciamento têm permitido o estudo de organismos modelo e não modelo de forma mais detalhada e não direcional. Análises deste tipo são promissoras para o estudo evolutivo de características complexas como o comportamento. Neste contexto, realizamos um amplo estudo sobre as bases moleculares envolvidas em diferentes características comportamentais relacionadas à evolução da socialidade em abelhas. Para tanto, o padrão global de expressão de genes, em espécies e fases do desenvolvimento distintas, foram analisados comparativamente através de múltiplas abordagens. No Capítulo 1, utilizamos contaminantes do transcriptoma da abelha solitária Tetrapedia diversipes para analisar os recursos florais utilizados por esta espécie em suas duas gerações reprodutivas. Neste estudo concluímos que a riqueza de espécies visitadas durante a primeira geração é muito maior do que durante a segunda geração, o que está provavelmente relacionado à floração de primavera durante o primeiro período reprodutivo. No Capítulo 2, verificamos que o padrão de expressão dos genes das fêmeas fundadoras possivelmente afeta o desenvolvimento larval em T. diversipes. O padrão bivoltino de reprodução desta espécie, com diapausa em uma das gerações, pode ser importante para a evolução do comportamento social. Além disso, entre os genes possivelmente envolvidos nessa característica, podemos encontrar genes mitocondriais e lncRNAs. Os resultados obtidos no Capítulo 3 sugerem que a especialização em subcastas de operárias ocorreu posteriormente nas diferentes linhagens de abelhas, envolvendo genes específicos. No entanto, esses genes afetam processos biológicos comuns nas diferentes espécies. Por sua vez, o Capítulo 4 apresenta um método promissor para a identificação de genes comportamentais em diferentes espécies de abelhas, através de uma análise de expressão comparativa. Com base nessas análises, 787 genes comportamentais, que possivelmente fazem parte de um toolkit eussocial em abelhas, foram encontrados. O padrão de metilação desses genes, em espécies com diferentes níveis sociais, indicou ainda que o contexto genômico da metilação pode ser relevante para eussocialidade. Os resultados obtidos nesses estudos apresentam novas perspectivas metodológicas e evolutivas para o estudo da evolução do comportamento social em abelhas / The social behaviour can be widely described as any intraspecific interaction in the animal life, including but not restricted to, female choice, species recognition, altruistic behaviour and the organization of animal society. Among the animal species most attuned to their social environment are the insects that, for example, in the Apini and Meliponini tribes, present a complex behaviour known as highly eusocial. Bees are an ideal group to study the evolution of the social behaviour because they have a great diversity of social life styles that evolved independently. The tribes Apini and Meliponini comprise only highly eusocial species whereas various levels of sociality can be detected in other tribes, being most bees indeed solitary. Although the evolution of eusociality has been the subject of many studies, the genetic changes involved in the process have not been completely understood. Results from studies conducted so far provide a starting point for the connection between specific genetic alterations and the evolution of eusocial behaviour. However fundamental questions about this process are still open. Recently, new sequencing technologies have allowed genetic studies of model and non-model organisms in a deep and non-directional way, which is promising for the study of complex characteristics. Herein, we present a broad analysis of the molecular bases of different behavioural characteristics related to the evolution of sociality in bees. To that end, the global expression pattern of genes involved in different behavioural features, in a number of bee species and distinct developmental stages, was comparatively studied using multiple approaches. Through these approaches different results were obtained. In Chapter 1, we used contaminant transcripts from the solitary bee Tetrapedia diversipes to identify the plants visited by this bee, during its two reproductive generations. These contaminant transcripts revealed that the richness of plant species visited during the first reproductive generation was considerably greater than during the second generation. Which is probably related to the floral boom occurring in spring during the first reproductive period. In Chapter 2, data suggests that the expression pattern in foundresses affect larval development in T. diversipes. The bivoltinism presented by this species, with diapause in one generation, might be an important feature for the evolution of sociality. Our results suggest that mitochondrial genes and lncRNAs are involved in this reproductive pattern. Results described in Chapter 3 indicate that specialization in worker subcastes occurred posteriorly in distinct bee lineages, driven by specific genes. However, these genes affected common biological processes in the different species. In Chapter 4 is described a promising analyses method to identify, comparatively, genes involved in bee social behaviour. Using this approach, we identified 787 behavioural genes that might be involved in social behaviour of different species. The methylation pattern of these genes suggests that the DNA context in which methylation marks occur, might be especially relevant to bee sociality. Results obtained here presents new methodological and evolutionary approaches to the study of social behaviour in bees

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