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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

Captive the life of our static buildings

Botha, P.R. (Philippus Rudolph) 05 December 2012 (has links)
This research project investigates the possibility of a public programme-overlay at the Union Buildings, situated on Meintjieskop on the western edge of the Pretoria inner city. The design of the Buildings was commissioned to Sir Herbert Baker to celebrate the newly formed Union of South Africa in 1910. The buildings were completed in 1913 and this research project attempts to commemorate the centenary of this landmark. The buildings’ current state does not allow for public participation and this seems unfortunate for both the public and the buildings. This dissertation attempts to reintroduce the Union Buildings to South Africans, the Pretoria public as well as international tourists by recording the memory of the buildings. The intervention is an interpretative archive to the life of the Union Buildings. The static, stereotomic nature of the buildings has ironically been shaped and forced into many different symbolic meanings through the ever-changing political and cultural dynamics of South Africa. The life of the buildings has been interpreted into five distinguishing symbolic-eras: Birth, Union, Oppression, Democracy and Power. The new intervention attempts to make these layered eras public. This project will also explore the relationship between architecture and craft. This study understands that architecture is more than ever becoming a two dimensional experience and this is believed to be a direct result of the dimension in which it is explored - between pen and paper. The investigation will contest this current condition in which architecture finds itself. Moreover the focus of this study will be to explore architecture in its final dimension, thus exploring the relationship between architecture and craft. In the true sense this is a study of the tekton. / Dissertation (MArch(Prof))--University of Pretoria 2012. / Architecture / MArch(Prof) / Unrestricted
32

Piano Sonata by Elliott Carter: A Foreshadowing of His Later Style, a Lecture Recital, Together with Three Recitals of Selected Works

Wilhite, Carmen Irene 05 1900 (has links)
The lecture recital was given January 22, 1977. A discussion of Elliott Carter's Piano Sonata emphasized those compositional techniques which foreshadowed important compositional procedures in many of his later works. The following compositions were discussed: Concerto for Orchestra, Double Concerto for Harpsichord and Piano with Two Chamber Orchestras, 8 Etudes and a Fantasy for Woodwind Quartet, Holiday Overture, Piano Concerto, Sonata for Flute, Oboe, Cello, and Harpsichord, Sonata for Violoncello and Piano, String Quartet No. 1, String Quartet No. 2, String Quartet No. 3, Variations for Orchestra. The Piano Sonata was Ty and Schumann. In addition to the lecture recital, three public solo recitals were performed. The first solo recital, performed on April 2, 1973, consisted of works by Bartok, Debussy The second solo recital, performed on October 28, 1974, included works by Bach and Liszt. The final solo recital, performed on March 7, 1976, consisted of works by Beethoven and Chopin. All four programs were recorded on magnetic tape and are filed, along with the written version of the lecture recital, as part of the dissertation. performed.
33

Die Predigt Johannes des Täufers. Konfessionelle Elemente in der religiösen Historienmalerei der Gegenreformation in den Niederlanden. Eine ikonologische Analyse des Motivs der Predigt Johannes des Täufers im 16. und frühen 17. Jahrhundert.

Hartmann-Janssen, Anja 29 January 2007 (has links)
Als bedeutende Gestalt der neutestamentlichen Überlieferung und Verkündigung, wird Johannes der Täufer in einer Vielzahl von Darstellungen in der bildenden Kunst verehrt. Das biblische Thema der Johannespredigt, das traditionell in der Malerei nur als Teil zyklischer Lebensdarstellungen gebräuchlich gewesen war, etablierte sich während der frühen Reformationszeit in Antwerpen (1520-1565) als eigenständiges Bildmotiv. Dies legte die Annahme nahe, dass ein Zusammenhang bestand zwischen den umwälzenden religiös-politischen Veränderungen und der ersten Konjunktur dieses Sujets. Nach einer Zäsur zur Zeit der Bilderstürme und der Teilung der Niederlande in den katholischen Süden und den calvinistischen Norden, erlebte die Johannespredigt Anfang des 17. Jahrhundert eine zweite auffällige Konjunkturphase, die bis zur Mitte des Jahrhunderts andauerte. Interessant hierbei, dass das Motiv, dass zunächst durch eine lokale, dominant protestantische Ikonographie geprägt wurde, nun sowohl in den calvinistisch regierten Nordprovinzen, als auch in den katholischen Südstaaten anzutreffen war. Die historischen Gründe dieser Entwicklung und die konfessionelle Dimension des Motivs, seine Bildkultur in der Zeit frühen Konfessionalisierung, bilden die zentralen Untersuchungsschwerpunkte dieser Dissertation. Die Analyse verdeutlicht, wie in diesem Prozess die verschiedenen Parteien mit gemeinsamen Symbolen umgehen, die zwar gemeinsam bleiben, aber deutlich differenzierte Bedeutungen gewinnen.
34

Gestaltung - Vordemberge-Gildewarts universales Prinzip in freier und angewandter Kunst

Meyering, Judith 17 December 2004 (has links)
This dissertation gives new results in regard to interpretations and explanations for the term Gestaltung on the constructivist Friedrich Vordemberge-Gildewart. The first part shows VG as a theoretican and is based on his theoretical writings of the twenties; the second part deals with his works as paractical artist. The wiritings shows his postulates on art and artist concerning formal-aesthetic, gestalt-psychological and social-utopian aspects. The formation-principle is described as an all-purpose method arranged in several layers, based on working processes in building elements, series and transforming. With the union of art and living, VG demanded a new-organization of the environment, so that all branches of his work has been of equal value, similar to the Bauhaus and the Dutch Stijl-group. The second part shows the practical realization of his theoretical principal in free and applied art: free constructions, architecture, design of furniture and typography are compared and analyzed.This work offers a new start in the correlation of Gestalt-psychology and art. For the first time, it will be questioned, if laws and qualities of Gestalten can be applied on constructivist art. The results are shown on actual examples. New connections were found in case of abstract film and the performance of series of movements in absolute art.These interdisciplinary dissertations not only joins explorations on history of art, theory of art and psychology, but delivers a wide and thoroughly view inside the different sections of free and applied art of the twenties.
35

Die Bildgenese in der informellen Malerei als Prozess der Selbstorganisation am Beispiel Emil Schumachers

Waruschewski-Segschneider, Gabriele 24 April 2003 (has links)
Ein Bild von Schumacher stellt ein natürliches, hochgradig komplexes Ordnungsgebilde als Resultat eines dynamischen, komplexen Prozesses dar. Dieser läßt sich als ein sich selbst organisierender Prozess, als regelhaft beschreiben und erklären. Das fertige Bild zeigt aufgrund von Kooperation und Koordination der Elemente des offenen Produktionssystems und der Wechselwirkung von Zufall und Notwendigkeit, wozu Fluktuation und Symmetriebrüche gehören als Resultat seiner Selbstorganisation seinen optimalen stabilen Ordnungszustand. Das Konzept der Selbstorganisation in der Synergetik zeigt auf, dass die Strukturierungsprozesse in der Natur strengen Gesetzen folgen. Mit Hilfe dieses Konzepts lassen sich die Regeln der Bildgenese der informellen Malerei erklären. Damit distanziere ich mich von der konventionellen Bewertung der Informellen bzw. der Malerei Schumachers, welche die Bildentstehung allein aus dem vermeintlich absoluten Chaos und damit aus dem Unregelhaften der Psyche ableiten. Es zeigt sich daher, dass die konventionelle Kunsttheorie in ihrem Urteil über die Entstehung der informellen Malerei bezweifelt werden darf. In dem Faktum, dass dem Künstler ein bewusster Entscheidungsspielraum zugestanden wird, ist seine konstitutive Funktion als bewusst handelndes Subjekt klar herausgestellt. Schumacher ist kein willenloser Automat und der Malprozess funktioniert nicht wie der Ablauf eines Uhrwerks. Er ist auch nicht der Spielball des Zufalls. Vielmehr verdeutlicht sich im Handeln des Künstlers seine Verantwortlichkeit, indem er ein mitgestaltender Teil eines offenen dynamischen Systems ist. Deutlich wird zudem die Aktualität seiner Malerei und damit die der informellen Malerei insgesamt. Die Aktualität ist darin begründet, dass sie die Entstehungsprozesse von Strukturen in einer Art und Weise thematisiert, die neuesten wissenschaftlichen Erkenntnissen entspricht.
36

Mucius Scaevola vor Porsenna. Frühneuzeitliche Auffassungen einer römischen Bürgertugend in der europäischen Malerei vom 15.-18. Jahrhundert

Garen, Andrea 07 January 2004 (has links)
Das Motiv "Mucius Scaevola vor Porsenna" zeigte den römischen Helden Mucius Scaevola bei seiner sprichwörtlich gewordenen Tat, wie er seine Hand in das Feuer hält. Die Dissertation untersucht die Rezeptionsgeschichte der antiken Historie in der europäischen Malerei der Frühen Neuzeit. Grundlage ist eine quantitative Analyse der Bilder zu diesem Thema, die den Überblick zu der Bildproduktion schuf und die Hauptakzente der Studie festlegte. Den chonologischen Rahmen bildet die vornehmliche Entstehungszeit, von den Anfängen im 15. Jahrhundert bis in das 18. Jahrhundert hinein. Ein geographisches Zentrum ist zunächst Italien, wo das Motiv seinen Ursprung hatte. Hier wird erstmals die hervorgehobene Bedeutung des Sujets im kommunalen Raum deutlich, während es in päpstlichen Aufträgen eher eine untergeordnete Rolle spielt. Auch jenseits der Alpen wird das Thema vor allem in stadtbürgerlichen Kreisen populär, beispielsweise an und in Rathäusern. Dabei etabliert sich eine eigene Bildgestaltung, die protestantische Haltungen gegenüber dem Kaiser erkennen läßt.Einen weiteren Schwerpunkt bildet das Gemälde von Rubens, der das Motiv im frühen 17. Jahrhundert am spanischen Hof einführte. Den Abschluß schließlich bilden die spätbarocken, zumeist monumentalen Gemälde des venezianischen Adels. Durch die Analyse ausgewählter Werke werden die unterschiedlichen Motivtypen definiert, die im Kontext der jeweiligen sozialen und politischen Verhältnisse ausgebildet wurden. Es sind die Abweichungen in der Anwendung der Bildtradition, die Aufschluß auf spezifische Positionen der Auftraggeberschaft geben. Die Studie erklärt die verschiedenen Motivtypen und deren Wandel in ihrer sozialen Situierung und liefert so eine Überschau zur Geschichte des Motivs "Mucius Scaevola vor Porsenna". Sie versteht sich damit als Beitrag zur Sozialgeschichte der Historienmalerei, indem sie eine historische Geographie der Heldenhistorie und ihrer Konjunkturen aufzeigt.
37

Pesquisa de mutações em genes envolvidos na diferenciação e manutenção das células germinativas em pacientes portadores de distúrbio do desenvolvimento gonadal 46,XX / Mutation analysis of genes involved in differentiation and maintenance of germ cells in patients with 46,XX disorders of gonadal development

Santos, Mariza Augusta Gerdulo dos 07 July 2010 (has links)
Diversos genes expressos durante a diferenciação das células germinativas atuam no desenvolvimento ovariano. A diferenciação das células somáticas ovarianas depende do número de células germinativas pré-meióticas que migram para a fenda gonadal. A expressão espaço-temporal de genes envolvidos na diferenciação dessas células e a posterior sobrevivência dos oócitos meióticos são de interesse no estudo dos distúrbios do desenvolvimento sexual (DDS) 46,XX. Entre os genes envolvidos nesses processos estão o NANOS3, BMP15 e STRA8. O NANOS3, uma molécula de ligação ao RNA que bloqueia a via apoptótica, assegura a sobrevivência das células germinativas durante sua migração para o interior da gônada. O STRA8 atua no início da meiose das células germinativas na gônada de embriões XX, sendo o primeiro sinal de dimorfismo gonadal. Por outro lado a subseqüente sobrevivência dos oócitos é controlada por fatores de transformação e crescimento como o BMP15, que promove a diferenciação das células da granulosa que por sua vez participam indiretamente da diferenciação dos oócitos e das células da teca. Neste trabalho pesquisamos a presença de mutações inativadoras nos genes NANOS3 e BMP15 em 45 pacientes com disgenesia gonadal (DG) 46,XX (10 casos familiais) e 40 pacientes com amenorréia secundária sem mutação nos genes FSHR e SF1. Também pesquisamos mutações nas regiões promotora proximal e codificadora do gene STRA8 de 45 pacientes com DG 46,XX, 16 pacientes com DDS ovotesticular 46,XX e 5 pacientes com DDS testicular 46,XX todos SRY negativo nos quais foram afastados defeitos moleculares nos genes DAX1, WNT4 e SOX9. No NANOS3 identificamos a mutação p.E120K em homozigose, a primeira associada ao fenótipo de DG 46,XX. Esta mutação missense foi identificada em duas irmãs com DG 46, XX e está localizada no domínio de ligação do tipo dedo de zinco da proteína. A nova mutação não foi identificada em 200 alelos controles pesquisados. No BMP15, uma nova mutação nonsense p.Q115X foi identificada em homozigose em duas irmãs com DG 46XX e em heterozigose em uma paciente com amenorréia secundária não familial. O códon de parada prematuro está localizado na região do pré-peptídeo da proteína. A nova mutação não foi identificada em 200 alelos controles pesquisados. No gene STRA8, um único polimorfismo previamente descrito na literatura (rs7805859) foi identificado na região codificadora e nenhuma alteração na região promotora proximal foi identificada. Em conclusão, identificamos pela primeira vez uma mutação no gene NANOS3 associado á DG 46,XX e confirmamos a participação do BMP15 neste fenótipo. Distúrbios do desenvolvimento gonadal 46, XX podem ser causados por mutações em genes envolvidos tanto na diferenciação quanto manutenção das células germinativas ovarianas. / Several genes expressing during the germ cell differentiation act in ovary development. The differentiation of somatic ovary cells depends of a pool of pre meiotic germ cells migration into the gonad. The space and temporal expression pattern of some genes involved with germ cell differentiation and the subsequently oocyte survival should be investigated in the disorders of sexual development (DSD) 46,XX. Some key genes involved with these processes are: NANOS3, BMP15 and STRA8. The NANOS3, a RNA binding molecule that blocks the apoptotic pathway, ensures the survival during migration into genital ridge. The STRA8 acts in the bigining of germ cells meioses in XX embryos and mark the first sexual gonadal dimorphism. In other hand the subsequently oocyte survival is controlled through transforming growth factor member BMP15, that guarantees granulose cells differentiation that acts indirectly in meiotic oocyte and theca cells differentiation. In this work we searched for the presence of inactivating mutations in NANOS3 and BMP15 in 45 patients with 46XX gonadal dysgenesis (10 familial cases) and 40 patients with secondary amenorrhea without FSHR and SF1 mutation. We also searched for inactivating mutations in coding and proximal promoter region of STRA8 in 45 patients with 46XX gonadal dysgenesis, 16 ovotesticular disorder of sex development (DSD) patients and five 46XX testicular DSD patients all SRY negative and molecular defects in DAX1, WNT4 and SOX9 gene. In NANOS3 we identified the mutation p.E120K in homozygous state, the first associated with DG 46,XX phenotype. This missense mutation was identified in two sisters with 46XX GD and affects a zinc finger domain of the protein. The new variant was absent in 200 control alleles. In BMP15, a new nonsense mutation p.Q115X was identified two sisters in homozygous state and in one sporadic case of secondary amenorrhea in heterozygous state. The premature codon STOP affects the pro-peptide domain of the protein. The new variant was absent in 200 control alleles. In STRA8, only a previously described polymorphism (rs7805859) was identified without any other variation in coding or proximal promoter region. In conclusion, we identified for the fist time mutation in NANOS3 associated with DG 46XX and corroborate the role of BMP15 in this phenotype. Disorders of gonadal development 46,XX may be involved with differentiation and maintenance of ovarian germ cells.
38

Pesquisa de mutações nos genes FGF9 e FGFR2 em pacientes portadores de distúrbios do desenvolvimento sexual 46,XY por anormalidades no desenvolvimento gonadal / Search for mutations on FGF9 and FGFR2 genes in patients with 46,XY disorders of sexual development by gonadal abnormalities

Machado, Aline Zamboni 11 July 2012 (has links)
Introdução: Várias evidências em estudos de animais knockout sugerem a efetiva participação dos genes Fgf9-Fgfr2 no processo de determinação testicular. Animais XY knockout para os genes Fgf9 e Fgfr2 apresentam reversão sexual como consequência da alteração na cascata de eventos masculinizantes nas gônadas fetais. Até o momento, mutações inativadoras dos genes FGF9-FGFR2 não foram descritas em pacientes 46, XY portadores de disgenesia gonadal. Objetivos: Pesquisar a presença de mutações inativadoras nos genes FGF9 e FGFR2 em pacientes portadores de DDS 46,XY por anormalidades do desenvolvimento gonadal. Casuística e Métodos: Trinta e três pacientes com disgenesia gonadal 46, XY, 11 com a forma completa e 22 com a forma parcial. As regiões codificadoras dos genes FGF9 e FGFR2 de todos os pacientes foram amplificadas e sequenciadas. As investigações quanto a presença de deleções foram realizadas usando-se a técnica de MLPA (Multiplex ligation-dependent probe amplification). Resultados: Mutações ou deleções nos genes FGF9 não foram encontradas em nenhum dos pacientes estudados, apenas alguns polimorfismos previamente descritos. No gene FGFR2 não foram encontradas deleções. Uma nova variante não sinônima em heterozigose, c.1358 C>T (p.Ser453Leu), localizada no exon 10 do FGFR2 foi encontrada em duas irmãs com disgenesia gonadal parcial 46,XY. A mãe é portadora da variante alélica e o estudo de 147 indivíduos controles não identificou a presença desta variante. A análise da variante em sites de previsão, PolyPhen, SIFT e Mutation Taster indicou que a nova proteína FGFR2 é possivelmente danificada. Conclusões: Se esses resultados dos sites de previsão forem confirmados em estudos funcionais futuros a participação do gene FGFR2 na determinação gonadal masculina em humanos estará comprovada / Introduction: Several evidence in animal studies \"knockout\" suggest the effective participation of Fgf9-Fgfr2 genes in testicular determination process. Animals XY \"knockout\" for Fgf9 and Fgfr2 genes exhibit sex reversal as a result of the change in the cascade of masculinizing events in fetal gonads. To date, So far inactivating mutations of FGF9 and FGFR2 genes have not been described in 46,XY patients with gonadal dysgenesis. Objectives: To investigate the presence of inactivating mutations in the FGF9 and FGFR2 gene in patients with 46,XY DSD by gonadal abnormalities. Casuistic and Methods: Thirty-three patients with 46,XY gonadal dysgenesis, 11 with the full form and 22 with the partial form. The coding regions of FGF9 and FGFR2 genes of all patients were amplified and sequenced. Investigations on the presence of deletions were made using the MLPA technique (\"Multiplex ligation-dependent probe amplification\"). Results: Mutations or deletions in the FGF9 gene were not found in any of the patients studied, only a few polymorphisms previously described. FGFR2 gene deletions were not found. A new non-synonymous variant in heterozygosis, c.1358 C> T (p.Ser453Leu) located in exon 10 of FGFR2 was found in two sisters with 46,XY partial gonadal dysgenesis. The mother is a carrier of the variant allele and the study of 147 control subjects did not identify the presence of this variant. The analysis of the variant on prediction sites, \"PolyPhen\", \"SIFT\" and \"Mutation Taster\" indicated that the new FGFR2 protein is possibly damaged. Conclusions: If the results of the prediction sites are confirmed by future functional studies the participation of the FGFR2 gene in human male gonadal determination will be proven
39

Papel do gene DHX37 na etiologia dos distúrbios do desenvolvimento sexual 46,XY associados a anormalidades do desenvolvimento gonadal / Role of DHX37 gene in the etiology of 46,XY disorders of sex development associated with abnormalities of gonadal development

Silva, Thatiana Evilen da 27 November 2017 (has links)
Os distúrbios do desenvolvimento sexual (DDS) 46,XY por anormalidades do desenvolvimento gonadal são doenças genéticas heterogêneas. Os testes genéticos que utilizam o sequenciamento de genes candidatos pelo método de Sanger é efetivo para o diagnóstico etiológico em menos de 40% desses pacientes. O sequenciamento de nova geração é uma ferramenta eficaz no diagnóstico de pacientes com DDSs. No presente estudo, utilizamos o sequenciamento exômico paralelo em larga escala (SEPLE) para identificar variantes alélicas potencialmente causadoras dos DDSs. Pacientes com síndrome de regressão testicular embrionária (SRTE) familial, membros de duas famílias brasileiras não relacionadas (família 1: dois irmãos afetados e pais não afetados e família 2: indivíduo índice, irmã não afetada e sobrinho afetado, filho da irmã do índice) foram selecionados inicialmente. Estes pacientes apresentavam micropenis, testículos ausentes ou disgenéticos e ausência de útero. O DNA genômico foi extraído de leucócitos de sangue periférico e o SEPLE foi realizado usando a plataforma Illumina-HiSeq-2500. Uma nova variante em heterozigose, c.923C > T, (p.Arg308Gln), no DHX37 foi identificada em todos os membros afetados das duas famílias brasileiras. O sequenciamento por Sanger confirmou a presença da variante em todos os afetados, no pai não afetado da F1 e na mãe não afetada do F2. A presença de efeito fundador da variante nestas duas famílias foi excluído, através da análise de 29 marcadores localizados no cromossomo 12q. Trinta e cinco pacientes com 46, XY DDS por anormalidades do desenvolvimento gonadal (6 com SRTE e 29 com disgenesia gonadal) esporádicos foram incluídos na pesquisa de variantes no DHX37 por Sanger ou por painel de genes candidatos (Plataforma Illumina-HiSeq-2500). As variantes c.923C > T, (p.Arg308Gln) em heterozigose e a variante c.451G > A, (p.Arg151Trp) em homozigose foram identificadas no DHX37 em dois pacientes com SRTE esporádicos. As variantes c.142C > T (p.Ala48Thr) e c.2020G > A (p.Arg674Trp) foram identificadas em heterozigose em dois pacientes esporádicos com disgenesia gonadal (DG). De acordo com o American College of Medical Genetics e Genomics guideline (ACMG), as variantes foram classificadas como provavelmente patogênicas (p.Arg308Gln e p.Arg674Trp), variante de significância clínica incerta (p.Arg151Trp) e variante benigna (p.Ala48Thr). Três variantes identificadas no DHX37 eram causadoras de doença em mais de três das ferramentas de previsão in silico utilizadas. Nenhuma das novas variantes no DHX37 foi encontrada nas bases de dados da população disponíveis (EXAC, 1000GENOME, ESP6500, gnomAD e abraOM) com uma frequência maior do que 0,01%. O padrão de metilação da região promotora do DHX37 dos membros afetados e não afetados das famílias 1 e 2 e controles femininos e masculino foi analisado utilizando o ensaio Infinium Methylation EPIC BeadChip (Illumina). Um sítio CpG hipometilado na região promotora do DHX37 foi observado apenas no pai da F1 quando comparado com as amostras dos filhos afetados, membros da F2 e controles. A análise imuno-histoquímica do padrão de expressão da proteína DHX37 foi realizada em amostras de testículos de oito indivíduos com diferentes idades cronológicas. Esta analise revelou que no tecido testicular de recém-nascidos, indivíduos em idade puberal e adultos, o DHX37 estava expresso em células germinativas em diferentes estágios de maturação (presentes nas espermatogonias, espermatócitos e espermátides e ausente nos espermatozoides). Este achado sugere que a proteína DHX37 pode ter um papel no processo de desenvolvimento das células germinativas. O DHX37 (12q24.31) codifica uma proteína DEAH (Asp-Glu-Ala-His) que pertence às famílias RNA helicases cujos membros estão envolvidos em quase todos os processos relacionados ao RNA, bem como ao controle do crescimento, proliferação e processos de diferenciação celular. Pacientes descritos com deleções na região 12q24.31, que contém o DHX37, apresentavam características sindrômicas e anormalidades genitais, como hipospadias ou micropenis. A presença de anormalidades genitais nestes pacientes reforça a hipótese de que o DHX37 está envolvido na etiologia dos DDSs 46,XY. Em conclusão, identificamos fortes evidências de um novo gene, o DHX37, envolvido no processo de desenvolvimento e manutenção das gônadas masculinas. Estudos complementares serão necessários para esclarecer o papel exato do DHX37 nas redes reguladoras de genes que controlam o desenvolvimento sexual humano / 46,XY disorders of sex development (DSD) associated with abnormalities of gonadal development are heterogeneous genetic diseases. Genetics testing using Sanger sequencing of candidate genes is effective for diagnosis in less than 40% of these patients. Next-generation sequencing has been a powerful genetic diagnostic tool in the investigation of DSD patients. In the present study, we used the whole exome sequencing (WES) to identify potentially DSD-causing allelic variants. Patients with familial embryonic testicular regression syndrome (ETRS) of two non-related Brazilian families (Family 1 (F1)- two affected brothers and the unaffected parents; Family 2 (F2)- index patient, his unaffected sister and an affected nephew, the son of the index\'s sister) were initially selected. The patients had micropenis, absent or dysgenetic testes and no uterus. Genomic DNA was extracted from peripheral blood leucocytes and WES was performed using the Illumina-HiSeq-2500 platform. A novel heterozygous variant, c.923C > T, (p.Arg308Gln), in the DHX37 gene was identified in all affected members of the two Brazilian families and in F1\'s father. Sanger sequencing confirmed the presence of the variant in the all of the affected members and in F1\'s father and in F2\'s mother. The presence of a founder effect in these families was investigated using 29 markers located on chromosome 12q and was ruled out. Thirty-five additional patients with sporadic 46,XY DSD associated with abnormalities of gonadal development (6 with ETRS and 29 with gonadal dysgenesis) were screened for variants in this novel candidate gene using Sanger or NGS-based targeted sequencing panel of DSD candidate genes (Illumina-HiSeq-2500 platform). The heterozygous variant c.923C > T (p.Arg308Gln) and the homozygous variant c.451G>A, (p.Arg151Trp) in the DHX37 were identified in two sporadic SRTE patients. The heterozygous variants c.142C > T (p.Ala48Thr) and c.2020G > A (p.Arg674Trp) were identified in two sporadic 46,XY gonadal dysgenesis (GD) patients. According to the American College of Medical Genetics and Genomics guidelines (ACMG) the variants were classified as likely pathogenic (p.Arg308Gln, p.Arg674Trp), variant of uncertain clinical significance (p.Arg151Trp and) and benign variant (p.Ala48Thr); and all three of them were disease causing in more than three of the in silico prediction tools used. None of the novel DHX37 variants identified were found in the available population databases (EXAC, 1000GENOME, ESP6500, gnomAD and abraOM) in more than 0.01%. Segregation analysis of DHX37 allelic variants was performed in 5 families and resulted in the autosomal dominant with incomplete penetrance and recessive inheritance patterns. DNA methylation pattern of the DHX37 promotor region of F1 and F2\'s affected and unaffected members and gender-matched controls was analyzed using the Infinium Methylation EPIC BeadChip (Illumina). One hypomethylated CpG site in the promoter region of the DHX37 was only observed in F1\'s father compared with the affected siblings, F2\'s members and controls. Immunohistochemical analysis of DHX37 protein expression pattern was performed on testis samples of eight individuals with different chronological ages. This analysis revealed that in the testicular tissue of newborns, pubertal and adults, the DHX37 was expressed in different stages of germ cells maturation (present in spermatogonia, spermatocytes and spermatids and absent in spermatozoa). This finding suggests that DHX37 protein might have a role in the process of germ-cells development. The DHX37 (12q24.31) encodes a DEAH (AspGlu- Ala-His) protein of the RNA helicase families, whose members are involved in almost all RNA-related process such as the control of cell growth, proliferation and differentiation processes. Previously described patients with 12q 24.31 deletions, which contains DHX37, showed syndromic features and genital abnormalities as hypospadias or micropenis. This phenotype reinforces the hypothesis that DHX37 is involved in the etiology of disorders in male sex development. In conclusion, a novel gene, the DHX37, involved in the process of development and maintenance of male gonads was identified. Further studies will be necessary to clarify the exact role of the DHX37 in the gene regulatory networks controlling human sex development
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Pesquisa de mutações em genes envolvidos na diferenciação e manutenção das células germinativas em pacientes portadores de distúrbio do desenvolvimento gonadal 46,XX / Mutation analysis of genes involved in differentiation and maintenance of germ cells in patients with 46,XX disorders of gonadal development

Mariza Augusta Gerdulo dos Santos 07 July 2010 (has links)
Diversos genes expressos durante a diferenciação das células germinativas atuam no desenvolvimento ovariano. A diferenciação das células somáticas ovarianas depende do número de células germinativas pré-meióticas que migram para a fenda gonadal. A expressão espaço-temporal de genes envolvidos na diferenciação dessas células e a posterior sobrevivência dos oócitos meióticos são de interesse no estudo dos distúrbios do desenvolvimento sexual (DDS) 46,XX. Entre os genes envolvidos nesses processos estão o NANOS3, BMP15 e STRA8. O NANOS3, uma molécula de ligação ao RNA que bloqueia a via apoptótica, assegura a sobrevivência das células germinativas durante sua migração para o interior da gônada. O STRA8 atua no início da meiose das células germinativas na gônada de embriões XX, sendo o primeiro sinal de dimorfismo gonadal. Por outro lado a subseqüente sobrevivência dos oócitos é controlada por fatores de transformação e crescimento como o BMP15, que promove a diferenciação das células da granulosa que por sua vez participam indiretamente da diferenciação dos oócitos e das células da teca. Neste trabalho pesquisamos a presença de mutações inativadoras nos genes NANOS3 e BMP15 em 45 pacientes com disgenesia gonadal (DG) 46,XX (10 casos familiais) e 40 pacientes com amenorréia secundária sem mutação nos genes FSHR e SF1. Também pesquisamos mutações nas regiões promotora proximal e codificadora do gene STRA8 de 45 pacientes com DG 46,XX, 16 pacientes com DDS ovotesticular 46,XX e 5 pacientes com DDS testicular 46,XX todos SRY negativo nos quais foram afastados defeitos moleculares nos genes DAX1, WNT4 e SOX9. No NANOS3 identificamos a mutação p.E120K em homozigose, a primeira associada ao fenótipo de DG 46,XX. Esta mutação missense foi identificada em duas irmãs com DG 46, XX e está localizada no domínio de ligação do tipo dedo de zinco da proteína. A nova mutação não foi identificada em 200 alelos controles pesquisados. No BMP15, uma nova mutação nonsense p.Q115X foi identificada em homozigose em duas irmãs com DG 46XX e em heterozigose em uma paciente com amenorréia secundária não familial. O códon de parada prematuro está localizado na região do pré-peptídeo da proteína. A nova mutação não foi identificada em 200 alelos controles pesquisados. No gene STRA8, um único polimorfismo previamente descrito na literatura (rs7805859) foi identificado na região codificadora e nenhuma alteração na região promotora proximal foi identificada. Em conclusão, identificamos pela primeira vez uma mutação no gene NANOS3 associado á DG 46,XX e confirmamos a participação do BMP15 neste fenótipo. Distúrbios do desenvolvimento gonadal 46, XX podem ser causados por mutações em genes envolvidos tanto na diferenciação quanto manutenção das células germinativas ovarianas. / Several genes expressing during the germ cell differentiation act in ovary development. The differentiation of somatic ovary cells depends of a pool of pre meiotic germ cells migration into the gonad. The space and temporal expression pattern of some genes involved with germ cell differentiation and the subsequently oocyte survival should be investigated in the disorders of sexual development (DSD) 46,XX. Some key genes involved with these processes are: NANOS3, BMP15 and STRA8. The NANOS3, a RNA binding molecule that blocks the apoptotic pathway, ensures the survival during migration into genital ridge. The STRA8 acts in the bigining of germ cells meioses in XX embryos and mark the first sexual gonadal dimorphism. In other hand the subsequently oocyte survival is controlled through transforming growth factor member BMP15, that guarantees granulose cells differentiation that acts indirectly in meiotic oocyte and theca cells differentiation. In this work we searched for the presence of inactivating mutations in NANOS3 and BMP15 in 45 patients with 46XX gonadal dysgenesis (10 familial cases) and 40 patients with secondary amenorrhea without FSHR and SF1 mutation. We also searched for inactivating mutations in coding and proximal promoter region of STRA8 in 45 patients with 46XX gonadal dysgenesis, 16 ovotesticular disorder of sex development (DSD) patients and five 46XX testicular DSD patients all SRY negative and molecular defects in DAX1, WNT4 and SOX9 gene. In NANOS3 we identified the mutation p.E120K in homozygous state, the first associated with DG 46,XX phenotype. This missense mutation was identified in two sisters with 46XX GD and affects a zinc finger domain of the protein. The new variant was absent in 200 control alleles. In BMP15, a new nonsense mutation p.Q115X was identified two sisters in homozygous state and in one sporadic case of secondary amenorrhea in heterozygous state. The premature codon STOP affects the pro-peptide domain of the protein. The new variant was absent in 200 control alleles. In STRA8, only a previously described polymorphism (rs7805859) was identified without any other variation in coding or proximal promoter region. In conclusion, we identified for the fist time mutation in NANOS3 associated with DG 46XX and corroborate the role of BMP15 in this phenotype. Disorders of gonadal development 46,XX may be involved with differentiation and maintenance of ovarian germ cells.

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