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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.
41

Investigação genômica de pacientes inférteis com oligozoospermia / Genomic investigation of infertile patients with oligozoospermia

Juliana Dourado Grzesiuk 13 December 2016 (has links)
A infertilidade afeta aproximadamente 15% dos casais, sendo atualmente reconhecido o envolvimento de fatores masculinos em metade dos casos. Alterações nas análises seminais são detectadas na maioria dos homens inférteis e a mais frequente é a baixa concentração de espermatozoides no ejaculado, conhecida como oligozoospermia. Vários estudos mostram uma forte relação entre fatores genéticos e a infertilidade, incluindo alterações cromossômicas e microdeleções do cromossomo Y, porém as causas da oligozoospermia ainda permanecem obscuras. O desenvolvimento de novas tecnologias de investigação vem possibilitando a detecção de alterações a nível genômico, como mutações e variações no número de cópias (CNVs). O presente trabalho teve por objetivo a caracterização genômica de homens com oligozoospermia sem causa definida, visando estabelecer correlação entre alterações no número de cópias e perdas de heterozigosidade (LOHs) e o fenótipo de infertilidade. Foram selecionados 18 pacientes após rigorosa avaliação clínica e investigação do histórico reprodutivo, sendo excluídos pacientes portadores de alterações cromossômicas e portadores de microdeleções do cromossomo Y. Seis homens comprovadamente férteis foram selecionados para o grupo controle. A investigação genômica de ambos os grupos, amostral e controle, foi realizada pela técnica de hibridação genômica comparativa em microarranjos (aCGH) utilizando a plataforma de resolução 180K (Agilent®,US), analisada pelo software Nexus 8.0. Foram detectadas alterações possivelmente patogênicas no cromossomo Y, no cromossomo X e em autossomos. Um ganho na região de AZFc envolvendo apenas os genes DAZ1 e DAZ4 foi detectado em nove pacientes e em quatro controles, sendo classificado como alteração benigna. Porém, alterações na região de AZFc possivelmente relacionadas ao fenótipo de oligozoospermia foram detectadas em três pacientes e incluíram extensas duplicações e deleções envolvendo, entre outros genes, as quatro cópias do gene DAZ. Após comparação de regiões selecionadas com a literatura e com diferentes bancos de dados genéticos, sugerimos que os genes PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 e ODF3B possam estar associados a alterações na produção espermática. Adicionalmente, entre os doze miRNAs presentes em regiões de LOH possivelmente relacionadas ao fenótipo de infertilidade, dez têm como alvo genes com funções relacionadas à espermatogênese e reprodução humana. Estudos adicionais a nível de expressão e sequenciamento gênico são necessários para confirmar a correlação entre o genótipo e o fenótipo de oligozoospermia. / Infertility affects about 15% of the couples, and it is currently recognized, that male factors are involved in about 50% of cases. Changes in seminal parameters are detected in most infertile men and the most common alteration, known as oligozoospermia, is a low concentration of sperm in the ejaculate. Several studies show a strong relationship between genetic factors and infertility, including chromosomal abnormalities and microdeletions of Y chromosome, however, the causes of oligozoospermia remain unclear. The development of new research technologies has allowed the detection of changes at genomic levels, such as mutations and copy number variations (CNVs). This study aimed to perform a genomic characterization of patients with idiopathic oligozoospermia to determine whether there is a correlation between changes of copy number and losses of heterozygosity (LOHs) in relation to the phenotype of infertility. Eighteen patients were selected for the cases after rigorous clinical examination and investigation of their reproductive history. Patients with chromosomal abnormalities or microdeletions of the Y chromosome were excluded. Six proven fertile men comprised the control group. Genomic investigation of both groups was performed by microarray comparative genomic hybridization (aCGH) using 4X180K platform (Agilent, US) analysed by Nexus 8.0 software. Potential pathogenic changes were detected on Y chromosome, as well as on the X and autosome chromosomes. A gain in AZFc region involving only DAZ1 and DAZ4 genes was detected in nine patients and four controls, and was considered as benign. However, changes in AZFc region, that could be related to the oligozoospermia phenotype were detected in three patients. These changes included extensive duplications and deletions involving the four copies of the DAZ gene together with copy number changes affecting other genes. After comparing the selected regions with the literature and with different databases, we suggest that changes such as LOH affecting PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 and ODF3B genes may influence sperm production. Our analysis indicates that, ten out of the twelve miRNAs present in LOH regions could be involved in the infertility phenotype and could have target genes with functions related to spermatogenesis and human reproduction. Additional studies involving gene sequencing and expression analysis are needed to confirm the the correlation between the genotype and oligozoospermia phenotype.
42

Uma abordagem integrativa usando dados de interação proteína-proteína e estudos genéticos para priorizar genes e funções biológicas em transtorno de déficit de atenção e hiperatividade / An integrative approach using protein-protein interaction data and genetic studies to prioritize genes and biological functions in attention-deficit/hyperactivty disorder

Leandro de Araujo Lima 22 July 2015 (has links)
O Transtorno de Déficit de Atenção e Hiperatividade (TDAH) é a doença do neurodesenvolvimento mais comum na infância, afetando cerca de 5,8% de crianças e adolescentes no mundo. Muitos estudos vêm tentando investigar a suscetibilidade genética em TDAH, mas sem muito sucesso. Este estudo teve como objetivo analisar variantes raras e comuns contribuindo para a arquitetura genética do TDAH. Foram gerados os primeiros dados de exoma de TDAH de 30 trios brasileiros em que o filho foi diagnosticado com TDAH esporádico. Foram analisados tanto variações de único nucleotídeo (ou SNVs, single-nucleotide variants) quanto variações de número de cópias (ou CNVs, copy-number variants), tanto nesses trios quanto em outros conjuntos de dados, incluindo uma amostra brasileira de 503 crianças/adolescentes controles, bem como resultados previamente publicados em quatro estudos com variação de número de cópias e uma meta-análise de estudos de associação ao longo do genoma. Tanto os trios quanto os controles fazem parte da Coorte de Escolares de Alto Risco para o desenvolvimento de Psicopatologia e Resiliência na Infância do Instituto Nacional de Psiquiatria do Desenvolvimento (INPD). Os resultados de trios brasileiros mostraram três padrões marcantes: casos com variações herdadas e somente SNVs de novo ou CNVs de novo, e casos somente com variações herdadas. Embora o tamanho amostral seja pequeno, pudemos ver que diferentes comorbidades são mais frequentes em casos somente com variações herdadas. Após explorarmos a composição de variações nos probandos brasileiros, foram selecionados genes recorrentes entre amostras do nosso estudo ou em bancos de dados públicos. Além disso, usando somente genes expressos no cérebro (amostras pós-mortem dos projetos Brain Atlas e Genotype-Tissue Expression), construímos uma rede de interação proteína-proteína \"in silico\" com interações físicas confirmadas por pelo menos duas fontes. Análises topológicas e funcionais dos genes da rede mostraram genes relacionados a sinapse, adesão celular, vias glutamatérgicas e serotonérgicas, o que confirma achados de trabalhos independentes na literatura indicando ainda novos genes e variantes genéticas nessas vias. / Attention-Deficit/Hyperactivity Disorder (ADHD) is the most common neuro-developmental disorder in children, affecting 5.8% of children and adolescents in the world. Many studies have attempted to investigate the genetic susceptibility of ADHD without much success. The present study aimed to analyze rare and common variants contributing to the genetic architecture of ADHD. We generated exome data from 30 Brazilian trios where the children were diagnosed with sporadic ADHD. We analyzed both single-nucleotide variants (SNVs) and copy-number variants (CNVs) in these trios and across multiple datasets, including a Brazilian sample of 503 children/adolescent controls from the High Risk Cohort Study for the Development of Childhood Psychiatric Disorders, and also previously published results of four CNV studies of ADHD involving children/adolescent Caucasian samples. The results from the Brazilian trios showed 3 major patterns: cases with inherited variations and de novo SNVs or de novo CNVs and cases with only inherited variations. Although the sample size is small, we could see that various comorbidities are more frequent in cases with only inherited variants. After exploring the rare variant composition in our 30 cases we selected genes with variations (SNVs or located in CNV regions) in our trio analysis that are recurrent in the families analyzed or in public data sets. Moreover, using only genes expressed in brain (post-mortem samples from Brain Atlas and The Genotype-Tissue Expression project), we constructed an in silico protein-protein interaction (PPI) network, with physical interactions confirmed by at least two sources. Topological and functional analyses of genes in this network uncovered genes related to synapse, cell adhesion, glutamatergic and serotoninergic pathways, both confirming findings of previous studies and capturing new genes and genetic variants in these pathways.
43

Alterações genômicas e epigenômicas nas manifestações anatomopatológicas e cognitivas da doença de Alzheimer / Genomic and epigenomic alterations in the anatomopathological and cognitive manifestations of Alzheimer\'s disease

Darine Christina Maia Villela 19 September 2014 (has links)
A doença de Alzheimer (DA) é a causa mais comum de demência na população, sendo responsável por cerca de 50 a 60% dos casos. Embora o diagnóstico clínico da doença na maioria das vezes seja acurado, a confirmação da DA só é feita post mortem através principalmente da caracterização dos dois tipos principais de lesões neurais: depósitos extracelulares de placas de β amiloide e emaranhados de proteína tau hiperfosforilada. Até o momento, o envolvimento de apenas quatro genes foi confirmado na etiologia da DA, três deles (APP, PSEN1 e PSEN2) associados à forma familial de herança mendeliana, que corresponde a um tipo raro e grave. No entanto, apesar de inúmeros trabalhos de associação genômica, (Genome wide association studies- GWAS) sugerirem uma possível participação de vários outros genes na suscetibilidade à manifestação da forma multifatorial da DA, o gene APOE, ainda é o único consistente e reproduzivelmente associado à doença. As descobertas derivadas dos GWAS investigando o papel de SNPs coletivamente explicam somente uma pequena porcentagem da variação herdada que contribui para o risco de desenvolver a DA. Atualmente, há novas abordagens para investigar a base genética do restante da variabilidade fenotípica herdada e que pode influenciar a suscetibilidade ao desenvolvimento de doenças complexas. O papel da variação do número de cópias de segmentos de DNA (Copy Number Variation - CNV) na genética de doenças complexas foi demonstrado por diversos estudos nos últimos anos e evidencia que desequilíbrios genômicos também podem contribuir significantemente para a resistência ou susceptibilidade a várias patologias. Outro aspecto que vem assumindo crescente importância é a análise de modificações epigenéticas que podem constituir um mecanismo molecular básico e contribuir diretamente para a patogênese da DA. Logo, este trabalho teve como objetivo principal investigar dois aspectos relacionados à DA: (1) a identificação de CNVs que podem estar contribuindo para o desenvolvimento da forma multifatorial da DA, usando a técnica de array-CGH, e (2) a análise de alterações do padrão global de metilação do DNA no córtex frontal de indivíduos com a forma multifatorial da DA, usando um microarranjo que interroga o status de metilação de 450.000 sítios CpGs. Em nossa investigação sobre desequilíbrios genômicos na DA, identificamos 6 CNVs raras com conteúdo gênico relevante para o fenótipo investigado. Dois indivíduos distintos do grupo DA apresentam microduplicações em genes que codificam diferentes subunidades do mesmo tipo de canal de Ca2+ dependente de voltagem, o tipo L. Além disso, dos outros genes selecionados como especialmente interessantes, 4 estão envolvidos em diferentes processos inflamatórios e 1 é responsável por codificar a enzima nicotinamida fosforibosiltransferase, participante importante da via de biossíntese da molécula nicotinamida adenina dinucleotídeo (NAD). A implicação de um possível envolvimento de mediadores da sinalização celular do Ca2+ e da via de biossíntese da NAD na etiologia da DA também foi reforçada pelos nossos resultados sobre o padrão de metilação do DNA na DA. Dois genes importantes para a homeostasia intracelular do Ca2+ e via de biossíntese da NAD apresentaram sítios CpGs diferenciamente metilados nos sujeitos com DA / Alzheimer\'s disease (AD) is the most common form of dementia in the population, corresponding to 50-60% of all cases. Although clinical diagnosis seems to be accurate, the definitive diagnosis of the disease can only be made by a post mortem neuropathological exam that certifies the presence of the two hallmarks of AD: the accumulation of extracellular senile plaques containing β-amyloid (Aβ) and the intracellular neurofibrillary tangles containing hyperphosphorylated tau protein. Four genes are known to be involved in the etiology of AD, three of them (APP, PSEN1 and PSEN2) are associated to the familial form of the disease, which show autosomal dominant inheritance and correspond to the more severe and rare type of AD. Despite many genome wide association studies (GWAS), APOE still remains the only unequivocal genetic risk factor associated to the multifactorial form of AD. The discoveries from GWAS using SNPs collectively explain only a small percentage of heritable variation that may contribute in AD risk. Currently, new approaches have been used to investigate the genetic basis of the phenotypical variability inheritance that can influence the susceptibility of complex diseases. The important role of DNA copy number variation (CNV) has been demonstrated by several studies over the last years and shows that genomic imbalances may also significantly contribute to resistance or susceptibility to various complex diseases. Additionally, there is now increasing interest in exploring how epigenetic modifications, in particular DNA methylation, could influence complex diseases etiology. Thus, the major aim of this work were to investigate two aspects related to the multifactorial form of AD: (1) identification of rare CNVs, using array-CGH, that could contribute to the development of the disease, and (2) analysis of the DNA methylation pattern in frontal cortex of individuals with AD. In our study, we identified 6 rare CNVs with relevant gene content to the investigated phenotype. Two distinct subjects with AD from our casuistic presented microduplications in genes that encode different subunits of the same type of Ca2+ voltage channel, the L-type. Furthermore, among the other selected genes, four are involved in different inflammatory process and one encodes the nicotinamide phosphoribosyltransferase enzyme, important mediator of nicotinamide adenine dinucleotide (NAD) biosynthesis. The implication of a possible involvement of Ca2+ intracellular signaling mediators and NAD biosynthesis pathway in the etiology of AD was also reinforced by our analysis of DNA methylation pattern. Interestingly, two important genes, one to intracellular Ca2+ homeostasis and the other to NAD biosynthesis pathway presented CpGs sites differently methylated in the AD subjects
44

Étude du rôle des miARN dans les pathologies vasculaires de l'oeil

Ménard, Catherine 12 1900 (has links)
Une des pathologies les plus répandues dans les pays développés est la dégénérescence maculaire liée à l’âge (DMLA). Elle se présente sous différentes formes dont la plus sévère est caractérisée par la présence de formation de néo-vascularisation provenant de la choroïde (CNV) migrant vers la rétine. Malheureusement, le diagnostic peut être seulement posé une fois que les symptômes apparaissent et que la vision est déjà affectée. Récemment, un vif engouement s’est porté sur les microARN (miARN), devenus des molécules d’intérêt pour le développement de biomarqueurs et représentant également un important potentiel thérapeutique. Nous avons donc émis l’hypothèse que l’identification de miRNA dans un contexte de DMLA avec CNV permettrait de caractériser leurs rôles, tant au niveau de l’identification de biomarqueurs que de nouvelles cibles thérapeutiques. Le premier objectif de notre projet était d’identifier chez l’humain une signature de miARN spécifique à la forme humide de la DMLA. Pour ce faire, nous avons réalisé un criblage des miARN dans l’humeur vitrée de patients. Nous avons observé une augmentation des niveaux de miR-146a et une diminution de miR-106b et miR-152 spécifique à la DMLA. Cette signature fut confirmée dans le plasma de cette même cohorte de patients. D’autre part, l’exploration de bases de données AMD Gene Consortium (AGC) et Ingenuity Pathway Analysis (IPA) a démontré une relation entre les miARN détectés et des mutations génétiques associées à la forme DMLA avec CNV. En effet, nous avons identifié un SNP (single-nucleotide polymorphism ou SNP) (rs1063320) dans un site de liaison de miR-152 du gène HLA-G. Le second objectif était d’explorer la possibilité d’utiliser, du point de vue thérapeutique, un des miARN identifiés au 1er objectif. Nous avons, tout d’abord, quantifié l’expression de miR-146a, miR-106b et miR152 dans un des modèles classiques de la DMLA avec CNV chez la souris (brûlures par laser). Le candidat retenu fut miR-106b, puisqu’en plus d’être impliqué dans l’angiogenèse, son expression dans le modèle animal reflétait de plus près celle obtenue chez les patients. Suite à ces résultats, nous avons: exploré A) le mécanisme influençant la diminution de l’expression de miR-106b et B) l’effet de sa surexpression sur l’angiogenèse. D’abord en A), nous avons observé une activation de la voie de PERK dans notre modèle animal de CNV induite par laser menant à une diminution de l’expression de MCM7 et du polycistron miR-106b~25. . Ensuite en B), nous avons pu observer l’effet anti-angiogénique de miR-106b sur la migration des cellules endothéliales in vitro et sur la formation de NV in vivo. L’action anti-angiogénique de miR-106b pourrait ainsi avoir un potentiel thérapeutique important sur la formation de la CNV dans la DMLA. / Age-related macular degeneration (AMD) is a leading cause of blindness worldwide affecting individuals over the age of 60. The neovascular form (NV AMD) is characterized by choroidal neovascularization (CNV) and is responsible for the majority of central vision impairment. Unfortunately, diagnostic of AMD can only be done after symptoms have appeared and loss of visual field occurred. Recently, there is a growing interest in microRNAs (miRNAs) for their eventual use in the development of new biomarkers or new therapeutic strategies. Our hypothesis is that wet AMD is associated with specific signature of several miRNAs that can be used as biomarkers for the disease. These miRNAs can be harnessed for therapeutic interventions. Our first objective was to identify a specific signature of miRNAs for wet AMD by using non-biased microRNA arrays and individual TaqMan qPCRs. We profiled miRNAs in the vitreous humour and plasma of patients with NV AMD. We identified a disease-associated increase in miR-146a and a decrease in miR-106b and miR-152 in the vitreous humour, which was reproducible in plasma. Moreover, miR-146a/miR-106b ratios discriminated patients with NV AMD with an area under the Receiver Operating Characteristic curve (ROC AUC) of 0,977 in vitreous humour and 0,915 in plasma, suggesting potential for a blood-based diagnostic. Furthermore, using the AGC and IPA database, we mapped a NV AMD-associated single nucleotide polymorphism (SNP) (rs1063320) in a binding site for miR-152-3p in the HLA-G gene. Our second objective was to explore the therapeutic potential of a specific miRNA (identified in objective 1). First, we explored the expression levels of miR-146a, miR-106b and miR-152 in the laser burn mouse model. We demonstrated that levels of miR-106b were significantly decreased in this mouse model of CNV. We divided this objective in two parts: Part A, explore mechanisms causing miR-106b downregulation and part B, study the therapeutic potential of miR-106b on the inhibition of angiogenesis and CNV formation. First, we showed that expression of the miR-106b-25 cluster is negatively regulated by the ER stress pathway of protein kinase RNA-like ER kinase (PERK) and a reduction in levels of MCM7, the host gene of miR-106b. �����Second, we demonstrated that therapeutic delivery of miR-106b to the retina with lentiviral vectors protects against aberrant retinal neovascularization in two distinct mouse models of pathological neo-vascularization. Results from this study suggest that miRNAs, such as miR-106b, have the potential to be used as multitarget therapeutics for conditions characterized by aberrant retinal neovascularization.
45

Reduced Expression of Single 16p11.2 CNV Genes Alters Neuronal Morphology

Jo, Adrienne 01 January 2019 (has links)
The 16p11.2 copy-number variant (CNV) represents a well-characterized, high-risk factor for autism spectrum disorder that additionally predisposes deletion carriers (16pdel) to increased head circumference, known as macrocephaly. The 16p11.2 CNV consists of 29 known genes, many of which are associated with neurobiological processes relevant for macrocephaly such as cell proliferation and apoptosis, differentiation and cell growth. Our lab’s previous work has demonstrated that induced pluripotent stem cell (iPSC)-derived neurons from 16pdel carriers show altered cellular morphology related to growth, which include increased soma size, total dendritic length and dendritic complexity. However, specific CNV genes responsible for these phenotypes have not been established. Here, we investigate the relationship between three 16p11.2 genes and the observed cellular phenotypes. We differentiated neurons from control iPSC-derived neural progenitor cells (NPCs) and used short hairpin RNA (shRNA) to reduce the expression of these CNV genes: KCTD13, MAPK3 and C16ORF53. We then assessed neuronal morphology by evaluating soma size, total dendritic length and dendritic complexity. We demonstrate that knocking down KCTD13 and C16ORF53 increases soma size and total dendrite length, respectively, similar to that observed in 16pdel iPSC-derived neurons. For this reason, we speculate that these genes may have a role in cell growth and might underlie macrocephaly. Thus, our study investigates genes in the 16p11.2 CNV that contribute to neuronal morphology, which may have a role in influencing brain size.
46

Genexpression und Wirkung von Faktoren der Blutgerinnungskaskade und des Komlementsystems in humanen retinalen Pigmentepithel (RPE)-Zellen

Dott, Britta 28 March 2012 (has links) (PDF)
Eine lokale Aktivierung des Komplementsystems im RPE ist ein pathogener Faktor der AMD. Neben der Wirkung von angiogenen Faktoren wie VEGF könnte eine Aktivierung des Blutgerinnungssystems im RPE dazu beitragen, dass sich aus einer trockenen eine feuchte AMD entwickelt. Dies könnte auf mehreren Ebenen geschehen: Gerinnungsfaktoren könnten die Expression der Komplementfaktoren und der angiogenen Faktoren regulieren sowie Wirkungen auf die Proliferation und Migration der RPE-Zellen besitzen. Eine Stimulierung der Proliferation und Migration der RPE-Zellen trägt zur Ausbildung von CNV-Membranen bei. Es ist aber bis jetzt nichts darüber bekannt, ob RPE-Zellen Faktoren des Blutgerinnungssystems exprimieren und ob z.B. Thrombin (als zentrale Protease des Blutgerinnungssystems) die Genexpression von Komplementfaktoren und von VEGF im RPE beeinflusst. Die Ziele der vorliegenden Dissertation waren daher: ● Nachweis der mRNA-Expression von Blutgerinnungs- und Komplementfaktoren im RPE; ● Nachweis der Wirkung von Thrombin auf die Expression von VEGF und von Komplementfaktoren, sowie auf die Proliferation und Migration der RPE-Zellen; und ● Nachweis der Wirkung der Komplementfaktoren C5a und C9 auf die Sekretion von VEGF und die Proliferation und Migration der RPE-Zellen.
47

Detekce CNV v bakteriálních genomech / CNV detection in bacterial genomes

Lacinová, Michaela January 2019 (has links)
This master thesis deals with analysis of structural variation of genome and with methods of its sequencing across all generations. Subsequently it contains a description of copy number variation and methods of its detection. The experimental part focuses on algorithm proposal for CNV detection according analysis and testing of uneven coverage in genome, variable representation of GC content and distance of sequence reads. Finally, the algorithm for detecting copy number variation is tested on genomic data of bacteria Klebsiella pneumoniae.
48

Einfluss genetischer Varianten auf den Fett- und Zuckerstoffwechsel bei Kindern

Windholz, Jan 07 January 2019 (has links)
Ziel dieser Arbeit war es Kandidatengene, die mit der Entwicklung von Adipositas assoziiert sind, auf eine veränderte Kopienzahl zu untersuchen. Zwar fanden wir in den von uns ausgewählten Genen keine Veränderungen der Kopienzahl, es gelang uns jedoch der Nachweis eines Nukleotid-Polymorphismus in SIM1 (rs3734354). Für diesen konnten wir erstmals eine Assoziation mit Parametern der Adipositas in einer Kinderkohorte zeigen. Weiterführend untersuchten wir die Effekte von Typ-2-Diabetes-assoziierten SNPs auf Glukosehomöostase und Insulinmetabolismus. Wir fanden eine Assoziation von rs2877716 (ADCY5) mit einer verminderten Insulinsekretion und von rs17271305 (VPS13C) mit einem erhöhten Nüchternglukosespiegel. Zusammenfassend unterstreichen die Effekte von SNPs wie VPS13C und ADCY5 die Komplexität der bisher unvollständig verstandenen Interaktionen von Alter, Genotyp und Phänotyp auf die Entwicklung des Typ-2-Diabetes. Für die Entwicklung der Adipositas scheinen Veränderungen der Kopienzahl in den untersuchten Genen bei übergewichtigen Kindern eine untergeordnete Rolle zu spielen. Weiterführende Arbeiten sind zur Erklärung der Heritabilität beider Krankheitsbilder und der komplexen Interaktionen von Phänotyp und Genotyp notwendig.:1 Bibliographische Beschreibung 2 Einführung 2.1 Bedeutung und Interaktion von Diabetes und Adipositas 2.2 Überblick Genetik Adipositas und Typ-2-Diabetes: Epidemiologie, Monogen vs. Polygen und Methodik 2.3 Der Leptin-Melanocortin Kreislauf 2.4 Überblick über Gene des Leptin-Melanocortin Kreislaufs (Leptin, POMC, MCR, SIM1) 2.5 Von Adipositas zu Diabetes 2.6 Charakteristik der Typ-2-Diabetes Kandidatengene (GIPR, ADCY5, GCKR, VPS13C) 2.7 Ziele der Arbeit 3 Publikation 1 'Copy number variations in “classical” obesity candidate genes are not frequently associated with severe early-onset obesity in children' 4 Publikation 2 'Effects of Genetic Variants in ADCY5, GIPR, GCKR and VPS13C on Early Impairment of Glucose and Insulin Metabolism in Children' 5 Zusammenfassung der Arbeit 6 Literaturverzeichnis 7 Anlagen 7.1 Supplementary Methods, Publikation 1 7.2 Supplementary Methods, Publikation 2 7.3 Erklärung über die eigenständige Abfassung der Arbeit 7.4 Erklärung über den wissenschaftlichen Beitrag des Promovenden an der ausgewählten Publikation 7.5 Lebenslauf 7.6 Publikationsverzeichnis 7.7 Danksagung
49

Genexpression und Wirkung von Faktoren der Blutgerinnungskaskade und des Komlementsystems in humanen retinalen Pigmentepithel (RPE)-Zellen

Dott, Britta 08 March 2012 (has links)
Eine lokale Aktivierung des Komplementsystems im RPE ist ein pathogener Faktor der AMD. Neben der Wirkung von angiogenen Faktoren wie VEGF könnte eine Aktivierung des Blutgerinnungssystems im RPE dazu beitragen, dass sich aus einer trockenen eine feuchte AMD entwickelt. Dies könnte auf mehreren Ebenen geschehen: Gerinnungsfaktoren könnten die Expression der Komplementfaktoren und der angiogenen Faktoren regulieren sowie Wirkungen auf die Proliferation und Migration der RPE-Zellen besitzen. Eine Stimulierung der Proliferation und Migration der RPE-Zellen trägt zur Ausbildung von CNV-Membranen bei. Es ist aber bis jetzt nichts darüber bekannt, ob RPE-Zellen Faktoren des Blutgerinnungssystems exprimieren und ob z.B. Thrombin (als zentrale Protease des Blutgerinnungssystems) die Genexpression von Komplementfaktoren und von VEGF im RPE beeinflusst. Die Ziele der vorliegenden Dissertation waren daher: ● Nachweis der mRNA-Expression von Blutgerinnungs- und Komplementfaktoren im RPE; ● Nachweis der Wirkung von Thrombin auf die Expression von VEGF und von Komplementfaktoren, sowie auf die Proliferation und Migration der RPE-Zellen; und ● Nachweis der Wirkung der Komplementfaktoren C5a und C9 auf die Sekretion von VEGF und die Proliferation und Migration der RPE-Zellen.
50

Complement Component C4 in Human Systemic Lupus Erythematosus: from Genetic Deficiencies to Copy-Number Variations

Wu, Yee Ling 27 August 2009 (has links)
No description available.

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