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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.
251

Estudo da diversidade dos genes MC1R e SLC24A5 em populações globais: avaliação de aspectos evolutivos e ambientais / MC1R and SLC24A5 gene diversity among global populations: assessment of environmental and evolutionary aspects

Leonardo Arduino Marano 11 December 2015 (has links)
Dentre os vários marcadores genéticos existentes, alguns SNPs (Single Nucleotide Polymorphisms) podem estar associados à determinação de uma série de características fenotípicas (cor de pele, olhos e cabelos, estatura, forma do rosto, espessura do fio de cabelo) tendo sua predição um grande valor nas investigações forenses. Dentre os principais genes conhecidos por controlarem a pigmentação humana, através da produção da melanina, o SLC24A5 (solute carrier family 24, member 5) e o MC1R (melanocortin 1-receptor) apresentam um papel fundamental na melanogênese. O advento do sequenciamento de nova geração permitiu o processamento de várias regiões genômicas e indivíduos simultaneamente, aumentando a disponibilidade e precisão de dados de genomas completos, como alcançado em estudos como o 1000 Genomes Project. Nossas análises preliminares demonstraram que os dados de Fase 3 do 1000 Genomes são muito mais confiáveis do que as versões anteriores. Com esses dados, obtidos para 26 populações globais, foram realizadas análises populacionais (diversidade haplotípica, desequilíbrio de ligação, redes de haplótipo e de variância molecular) para os genes MC1R e SLC24A5 a fim de se compreender melhor seus padrões de diversidade, correlacionando-os à prováveis eventos de seleção natural que tenham moldado sua história evolutiva, como por exemplo a intensidade da radiação UV nas diferentes regiões geográficas. Alguns padrões foram encontradas entre os grupos africano, europeu e asiático, de acordo com a história evolutiva já descrita para estes grupos. Apesar disso, foi observado um padrão claro de varredura seletiva para o SLC24A5 nos resultados obtidos, como o alto desequilíbrio de ligação e baixa diversidade haplotípica. As análises da diversidade do SLC24A5 associadas com as zonas de incidência UV, no entanto, não apresentaram uma correlação clara entre a intensidade da radiação UV e a diversidade haplotípica / Among the various existing genetic markers, some SNPs may be associated with the determination of a series of phenotypic characteristics (skin, eyes and hair color, height, face shape, hair thickness) and its prediction could have a great value in forensic investigations. Among the major genes known to control human pigmentation through melanin production, SLC24A5 (solute carrier family 24, member 5) and MC1R (melanocortin-1 receptor) have a major role in melanogenesis. The advent of next-generation sequencing has enabled processing of several individuals and genomic regions simultaneously while increasing the availability and accuracy of whole genomes data, such as 1000 Genomes Project has achieved. Our preliminary analysis showed that Phase 3 data from the 1000 Genomes are far more reliable than previous versions. Using this data, obtained for 26 global populations, several analyzes were performed (haplotype diversity, linkage disequilibrium, haplotype networks and molecular variance) for MC1R and SLC24A5 in order to better understand their diversity patterns, correlating them to natural selection events which may have shaped their evolutionary history, such as UV radiation intensity in different geographical regions. Some patterns were found between African, European and Asian groups, according to the evolutionary history already described for these groups. Nevertheless, a strong pattern of selective sweep was observed for SLC24A5 in our data, such as high linkage disequilibrium and low haplotype diversity. Analysis of SLC24A5 diversity associated to UV, however, did not show a clear correlation between the UV radiation intensity and haplotype diversity
252

En kvalitativ syntes av anhörigas upplevelser under och efter närståendes plötsliga hjärtstopp

Leino, Marina January 2017 (has links)
Bakgrund: Ett hjärtstopp är ett ytterst allvarligt tillstånd som påverkar inte bara patienten själv utan hela familjen, speciellt en nära anhörig. Patienten svävar mellan liv och död, och om patienten överlever är det ofta med mer eller mindre bestående men. Vid patientens sida finns de anhöriga som vill vara nära, hjälpa och stöda sin närstående samtidigt som det också kan vara en mycket svår situation för dem. Syfte: Syftet med den här kvalitativa litteraturstudien var att belysa anhörigas upplevelser av en närståendes hjärtstopp, för att i framtiden bättre kunna tillmötesgå dem inom vården. Metod: En kvalitativ sammanfattande litteraturstudie baserad på åtta vetenskapliga artiklar som hade studerat anhörigas upplevelser under själva hjärtstoppet, på intensiv-vårdsavdelningen eller efter hemkomst. Resultat: Hjärtstoppet var en kaotisk och traumatisk upplevelse för den anhöriga. Patienten var viktigast, all fokus var på patienten men det lämnade ofta den anhöriga ensam med den oro och rädsla situationen framkallat. Tillgång till kontinuerlig information och professionellt bemötande var ytterst viktigt för den anhöriga. Möjligheten att få vara nära närstående dygnet runt ingav säkerhet och trygghet. Brist på information och uppföljning efter utskrivning och en känsla av att vara ensam med allt ansvar var återkommande teman. Slutsats: Att som anhörig vara nära vid ett hjärtstopp var en stark existentiell upplevelse där alla aspekter av delaktighet fanns beskrivna; att veta, att göra och att vara. För bästa resultat, ett delaktigt vårdande i ljuset, krävs en samverkan mellan den vårdande personalen, patient och anhörig. Mer stöd och uppmärksamhet bör i framtiden riktas även mot den anhöriga. / Background: Sudden cardiac arrest is a life threatening condition, not only affecting the patient but the whole family. The patient’s life is on hold and if the patient survives, this is often with more or less physical and psychological complications. Close to the patient a family member or relative, tries to support and help the patient while at the same time the situation may be extremely stressful for the relative. Aim: The aim of this qualitative literature review was to get a better understanding of family members lived experiences during a loved one’s sudden cardiac arrest, in order to better also support the relatives in healthcare. Method: A summary of the literature based on eight qualitative studies on the perceptions of family members experiences of a sudden cardiac arrest by a loved one; during the cardiac arrest, at the intensive care unit and after discharge from hospital. Results: The cardiac arrest was experienced as a chaotic and traumatic event by the relative. The patient was the most important person at the moment but at the same time it left the relative alone with her feelings of anxiety and fear that the situation induced. Receiving information continuously about their next of kin’s condition as well as a considerate and professional encounter with the intensive care unit staff was important for the relative. The possibility to stay with the patient at the intensive care unit felt comforting, reassuring and safe. Lack of information and follow up, as well as a feeling of being alone with the responsibility, was a common theme after discharge from the hospital. Conclusion: To be present during the next of kin’s cardiac arrest was a strong existential experience where all aspects of involvement and participation were described; to know, to do and to be. For best results, an involving care in the light, collaboration between the professional care, the patient and the family member is needed. More support and attention should be given to family members in the future.
253

Barn som anhöriga i ett västsvenskt ambulansområde : En pilotkartläggning / A survey of Children as next of kin within an ambulance service district in Western Sweden

Bjärbo, Magnus January 2018 (has links)
Antalet barn som anhöriga till patienter som erhåller vård och transport till sjukhus är okänt. Barn under 18 år kan ibland vara närvarande på hämtplatsen när ambulanssjukvården hämtar barnets anhörig. Hur många barn som anhöriga som är närvarande är okänt inom ett västsvenskt ambulansområde. Triagesystemet RETTS används vid triagering och bedömning av anhöriga till barnen. Syftet med studien är att kartlägga hur många barn som är närvarande då deras anhöriga ges vård, behandling och transport till en vårdinrättning vid prioritet 1 och 2 larm. En enkät skapades för att samla in data till studien. Barn som anhöriga finns även inom ambulanssjukvård. I denna studie identifierades 155 barn vid 95 ambulansuppdrag. Barn som anhörig ses till både vuxna, vanligen en förälder, som till barn. Ett flertal barn som anhöriga är närvarande när en anhörig påvisar svåra, kanske livshotande symptom. Sammanfattningsvis visade studien att stödet till barn och kunskapen om stöd fanns inte inom det ambulansområde där studien är genomförd. / Children as next of kin to patients who are treated by an ambulance nurse in Swedish ambulance service in unknown. Children under 18 years of age may sometimes be present when their parent or other next of kin, has to call the ambulance service due to illness or accident. How many children who experience their next of kin transported to hospital within a Western Swedish ambulance service district is unknown. The purpose of this survey is to identify how many children actually are present when their next of kin may need care and treatment from an ambulance service. Purpose: Survey how many children are present when an ambulance nurse cares and treats a next of kin due to illness or an accident, prioritized as priority 1 or 2. Method: a survey conducted by ambulance nurses in a western Swedish ambulance service. The survey has a quantitative design. Children as next of kin are present within a Swedish ambulance service district, in this survey 155 children was identified in a total of 95 ambulance missions. Children as next of kin are seen as adults, in most cases, a parent as well as children usually a sibling. Many children are present when their relative shows sign and symptoms of severe illness.
254

The future of next-generation sequencing for blood group genotyping and its implications in transfusion medicine

Halawani, Amr Jamal J. January 2016 (has links)
Alloimmunisation becomes a problem when serological discrepancies occur in matching antigens between donors and patients for blood transfusion. The rate of alloimmunisation has been increased especially in multiply transfused patients. Blood group genotyping (BGG) is a DNA-based assay that aids in reducing this situation. Currently, many platforms of BGG have become available, in which every technique has its own advantages and disadvantages. All these platforms lack the ability to identify novel alleles that might have an unknown clinical significance. The advent of next-generation sequencing (NGS) offers identification of the unprecedented alleles due to its basis of sequence-based typing. Moreover, it provides an extreme high-throughput which may be able to screen many donors and patients in a single run. In this project, two approaches have been developed in generating sequencing libraries followed by sequencing on the Ion Torrent Personal Genome MachineTM platform (Ion PGMTM). The first approach was amplicon-based target selection using Ion AmpliseqTM Custom Panel, designated as Human Erythrocyte Antigens and Human Platelet Antigens Panel (HEA and HPA Panel). This panel assay screens 11 blood group systems, as well as 16 human platelet antigens. The outcome was extraordinary, in particular four novel alleles had been identified out of 28 samples, one in the RHCE gene 208C > T (Arg70Trp) in exon 2 and three in the KEL gene. The first SNP was 331G > A (Ala111Thr) in exon 4. The second SNP was 1907C > T (Ala636Val) in exon 17 and the third SNP was 2165T > C (Leu722Pro) in exon 19. However, some issues occurred regarding co-amplification of homologous genes. The second approach was a long-range polymerase chain reaction (LR-PCR) based approach. This method provided a high resolution assay by amplification of entire genes, including the non-coding area, of the Kell and Rh blood group systems. The Kell blood group was initially utilised as a model in order to apply the same approach on the Rh system. Most alleles encoding the antigens of the Kell blood group, especially the high prevalence ones, were identified. The Rh LR-PCR approach was carried out by amplification of the RHD and RHCE genes with seven amplicons. For five RhD-positive samples no mutations were observed within the coding areas. On the other hand, five serotyped weak D samples were genotyped as; two weak D type 1, two weak D type 2 and one DAR3.1 weak partial D 4.0 (RHD*DAR3.01). Regarding the RHCE, the following antigens (C, c, E, c) were predicted properly from the sequencing data. Moreover, the RHCE*ceVS.02 was identified. 64 and 39 intronic SNPs were identified in RHD and RHCE genes, respectively. The intronic SNPs assisted the genotyping process by identifying the haplotype of interest. Interestingly, the novel allele identified in the RHCE gene by the HEA and HPA Panel was confirmed to belong to the RHCE gene by the LR-PCR approach, indicating the panel misaligned it to the RHD gene. In conclusion, NGS paves the way to be an alternative substitution to the previous molecular techniques. It would supplant the conventional serology for typing blood for transfusion.
255

Computational analyses of gene fusions, viruses and parasitic genomic elements in breast cancer

Fimereli, Danai 25 January 2018 (has links)
Breast cancer is the most common cancer in women and research efforts to unravel the underlying mechanisms that drive carcinogenesis are continuous. The emergence of high-throughput sequencing techniques and their constant advancement, in combination with large scale studies of genomic and transcriptomic data, allowed the identification of important genetic changes that take place in the breast cancer genome, including somatic mutations, copy number aberrations and genomic rearrangements.The overall aim of this thesis is to explore the presence of genetic changes that take place in the breast cancer transcriptome and their possible contribution to carcinogenesis. The aim of the first research study was the identification of expressed gene fusions in breast cancer and the study of their association with other genomic events. For achieving this, transcriptome sequencing and Single Nucleotide Polymorphism arrays data for a cohort of 55 tumors and 10 normal breast tissues were combined. Gene fusions were detected in the majority of the samples, with evident differences between breast cancer subtypes, where HER2+ samples had significantly more fusions than the other subtypes. The genome-wide analysis uncovered localization of fusion genes in specific chromosomes like 17, 8 or 20. Additionally, a positive correlation between the number of gene fusions and the number of amplifications was observed, including the association between fusions on chromosome 17 and the amplifications in HER2+ samples, which can be attributed to the highly rearranged genomes of these subtypes. Finally, the absence of highly recurrent fusions across this cohort adds to the notion that gene fusions in breast cancer are most likely private events, with the majority being “passenger” events. In the second research study, the aim was to identify a connection between viral infections and breast cancer by devising five different computational methods for the analysis of both transcriptome and exome data in a cohort of 58 breast tumors. Despite being able to detect viral sequences in our testing dataset, no significantly high numbers of viral sequences were detected in our samples. Specifically, viral sequences (~2-30 reads) were extracted belonging to viruses EBV, HHV6 and Merkel cell polyomavirus. Such low levels of viral expression direct against a viral etiology for breast cancer but one should not exclude possible cases of integrated but silent viruses.In the third research project, we analyzed in silico the transcriptional profiles of human endogenous retroviruses in breast cancer. Despite being scattered across the genome in large numbers, a number of ERVs are actively transcribed, consisting of a small percentage of the total mapped reads. Alongside protein coding genes and lncRNAs, they show distinct expression profiles across the different breast cancer subtypes with luminal and basal-like samples clear separating from each other. Additionally, distinct profiles between ER+ and ER- samples were observed. Tumor specific ERV loci show an association with the immune status of the tumors, indicating that ERVs are reactivated in tumors and could play a role in the activation of the immune response cascade.The results presented in this thesis exhibit only in a small fragment the diversity and heterogeneity of the breast cancer transcriptome. The strength of the sequencing techniques allows the in depth detection of different genomic events. Gene fusions should be considered as part of the breast cancer transcriptome but their low recurrence across samples indicates for a role as passenger events. Under the light of existing results, viral infections do not play a significant role in breast cancer. On the other hand, human endogenous retroviruses, despite originating from exogenous viruses, seems to exhibit transcriptional profiles similar to those of normal genes, indicating that they are part of the genome’s transcriptional machinery. / Doctorat en Sciences biomédicales et pharmaceutiques (Médecine) / info:eu-repo/semantics/nonPublished
256

Prevalence of microorganisms in reindeer(Rangifer tarandustarandus)and possible effects of climate changes.

Eklund, Ida January 2017 (has links)
The climate in the north is changing over time, which affects the nature in many ways. For instance, some microorganisms that cause infections might become more common. This might have negative consequences for reindeer husbandry. In Sweden, this is an industry that is relatively large. However, even though the reindeer is common in the north the knowledge about its diseases is limited.In this study the prevalence of microorganisms that may cause infection in reindeer was investigated. Comparisons between different sami villages and previous studies were performed to detect differences that could occur due to climate changes. The diseases and microorganisms that were analyzed with PCR were malignant catarrhal fever, herpes infections, Chlamydia sp. and bovine viral diarrhea (BVD). The cause of eye problems in reindeer was also investigated. BVD and bovine leukemia virus where analyzed with ELISA. Next generation sequencing where used for broader screening of samples for microorganisms that might be of interest of future analysis in more detailed follow-up studies.Since not enough samples were available at the time of this study findings could not be linked to changing climate. In the reindeer with eye infection Chlamydia sp., Moraxella sp. and Neisseria sp. can probably be involved causing disease. This should be further investigated to be able to determine whether it is true or not by analyzing samples from individuals without changes in the eyes. The prevalence of reindeers with antibodies against BVD has increased in Sweden since 2012. There will be further studies in this field with reindeers from other northern countries.
257

Närståendes upplevelser efter att en anhörig har begått suicid : En litteraturstudie baserad på självbiografier / Relatives’ experiences after a next of kin commits suicide : Literature study based on autobiographies

Aden, Najmo, Luwedde, Jalia January 2018 (has links)
Bakgrund:Suicid är en självdestruktiv handling som leder till döden och som ofta är en konsekvens av psykiskt lidande och sjukdom. Suicid leder till ett stort lidande för efterlevande närstående. Därför behöver sjuksköterskor sträva efter att fånga upp dessa närstående och hjälpa dem. Syfte: Syftet med studien är att beskriva närståendes upplevelser efter att en person har begått suicid för att skapa förståelse för hur sjuksköterskor kan bemöta närståendes behov. Metod: Studien är baserad på sju självbiografier som analyserades enligt Dahlborg-Lyckhages metod att analysera berättelser. Resultat: Närstående beskriver en stor sorg över suiciden, känslor som skuld, skam men även lättnad upplevs efter en anhörigs suicid. Närstående beskriver hur omgivningen undviker dem och att de upplever sig utpekade och isolerade efter en anhörigs suicid. Närstående beklagar sig också över att det inte erbjuds professionellt stöd och hjälp utan att de själva måste söka det. Konklusion: De närstående är främst i behov av professionellt stöd i form av stödsamtal och gemensamma samtal med resten av familjen. Dessutom är de närstående i behov av socialt stöd i form av stödgrupper från till exempel SPES. Sjuksköterskans roll blir att stödja de närstående i deras sorgeprocess. / Background: Suicide is self-destructive act that leads to death and is usually a consequence of mental illness and disease. Suicide also leads to great suffering for the relatives left behind. The nurse’s role in cases like these is therefore to acknowledge and support relatives in their grieving process. Aim: Is to describe relatives’ lived experiences after their next of kin commits suicide in order to create an understanding on how nurses can respond to their needs. Method: The study was based on seven autobiographies. Dahborg-lyckhage’s method for analyzing narratives was used to analyze the chosen biographies. Results: The results describe the relatives’ feelings like guilt, shame, relief among others and reactions after their next of kin’s suicide. They experienced avoidance by people in their surroundings. They also lacked professional support to assist them in their bereavement and had to reach out for it themselves. Conclusion: Nurses have a role to fulfill with supporting relatives in their grieving process with aim to help on improving their wellbeing and relieve their suffering. Information about support groups and helpful organizations like SPES as a form of social support can be very helpful in achieving this.
258

Identification de nouveaux gènes d'ataxies cérébelleuses récessives et intérêt du séquençage haut débit dans le diagnostic des ataxies d'origine génétique / Identification of new recessive cerebellar ataxias genes and interest of next generation sequencing in the diagnosis of genetic ataxias

Mallaret, Martial 23 September 2015 (has links)
Les ataxies cérébelleuses héréditaires sont un ensemble de pathologies neurodégénératives ou neuro-développementales rares responsables d’un handicap fonctionnel important. Nous décrivons la découverte dans deux familles consanguines avec une ataxie cérébelleuse, une épilepsie et un retard mental deux mutations homozygotes dans le gène WWOX à l’aide du séquençage de l’exome d’un des patients de chaque famille. Ce gène était connu comme un gène suppresseur de tumeur. Par une stratégie de capture ciblée de 57 gènes d’ataxies cérébelleuses sur une série de 155 patients, nous avons posé un diagnostic dans 20,6% des cas dont des mutations d’ANO10 et SYNE1. Des études multicentriques ont permis d’étendre les connaissances sur ces maladies et montrer l’existence de phénotypes sévères dans ARCA1.A partir de cette série, nous avons validé en aveugle la pertinence d’un algorithme diagnostique clinico-biologique proposé par l’article de Anheim dans le New England Journal of Medicine en 2012. / Hereditary cerebellar ataxias are a group of neurodegenerative or neurodevelopemental diseases responsible of major disability. We found thanks to exome sequencing mutations in the WWOX gene in two consaguineous families presenting with cerebellar ataxia, epilepsy and mental retardation. This gene was until recently only recognized to be a tumor suppressor.With a 57 ataxia genes targeted capture strategy, next generation sequencing in 155 patients found 20,6% of positive diagnosis, including several new mutations in ANO10 and SYNE1. Multi center studies allow to extend clinical knowledge with severes phenotypes especially in ARCA1.We validate a clinico-biological algorithm for recesssive ataxias diagnosis published by Anheim in the in New England Journal of Medicine, 2012 in a blinded manner.
259

Description et comportement des communautés bactériennes de la viande de poulet conservée sous atmosphère protectrice / Description and behavior of bacterial communities of chicken meat samples stored under modified atmosphere packaging

Rouger, Amélie 27 June 2017 (has links)
Contrôler les bactéries altérantes des aliments, notamment les produits carnés crus, est un enjeu majeur pour les industries agroalimentaires. Les conditions de stockage de la viande sous différentes atmosphères exercent une pression de sélection et modifient le comportement et le développement des communautés bactériennes initialement présentes. Des méthodes de séquençage à haut débit, utilisées pour caractériser différents écosystèmes microbiens, ont été appliquées pour étudier la dynamique des communautés bactériennes de la viande de poulet au cours du stockage.Nous avons développé une méthode pour constituer des écosystèmes microbiens standards dont la composition a été déterminée par pyroséquençage du gène de l’ARNr 16S. La présence de Brochothrix thermosphacta et de Pseudomonas parmi les espèces dominantes a été confirmée et nous avons mis en évidence que Shewanella et Carnobacterium étaient sous dominantes. Nous avons sélectionné deux écosystèmes pour effectuer des challenges tests reproductibles sur de la viande de poulet conservée sous 3 atmosphères couramment utilisées. Une analyse métatranscriptomique et métagénomique a été réalisée afin de savoir “Quelles bactéries étaient présentes ?”, “Qu’étaient-elles capables de faire?” et “Qu’exprimaient-elles?” suivant les conditions.Nous avons ainsi pu évaluer l’impact des mélanges gazeux sur la dynamique bactérienne et les fonctions exprimées par les bactéries suivant les contaminants initiaux. Cela nous donne des pistes pour fournir des indications afin d’optimiser la conservation de la viande en contrôlant les écosystèmes microbiens / Controlling spoilage microorganisms, especially in raw meat products, is challenging for the food industry.Storage conditions such as modified atmosphere packaging (MAP) have selective effects on the microbiota dynamics. Thanks to the recent developmentof next generation sequencing methods widely used for characterizing microbes in different ecosystems, we studied bacterial community dynamics during chickenmeat storage.We developed a method to constitute a standard meat microbial ecosystem hosting known bacterial species previously described by 16S rRNA sequencing. Our results confirmed the presence of Brochothrix thermosphacta and Pseudomonas and we also showed the presence of subdominant species as Shewanella and Carnobacterium. We selected 2 bacterial communities enabling reproducible challenge tests on meat during 9 days of storage at 4°C under 3 different atmospheres currently used in the industry.Metatranscriptomic and metagenomic analyses were performed to know “Who is there?”, “What can they do?” and “What are they expressing?” depending on the gaseous mixtures and on the initial microbiota.Consequently, we could evaluate the impact of storage atmosphere on the microbiotas dynamics and on the functions the bacteria expressed, depending on the storage condition and on the nature of the bacterial communities present. This led to indications of optimized storage conditions of poultry meat by managing their ecosystems.
260

Anrikning med Illumina Nextera XT sekvenseringsbibliotek

Aspelin, Jesper January 2017 (has links)
No description available.

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