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The feasibility of using two different methods of assaying for DNA polymer phisms has been assessed. They were Restriction fragment length polymorphisms (RFLPs) as revealed by a range of characterised Brassica cDNA sequences and Random amplified polymorphic DNA (RAPD). These techniques have been shown to reveal DNA polymorphisms between varieties of Brassica napus L. Further more, the sequence and organisation of a Hind III family of highly repetitive DNA sequences were also studied on Brassica napus L. RFLPs associated with rape extensin, ext A, and Brassica oleraceae self- incompatibility genes were observed when DNA samples from 19 commercial varieties of B. napus were analysed using the cDNA probes pRR566 (coding for root-specific extensin) and pBOS2 (coding for S(_5) self-incompatibility allele in B. oleraceae). Both cDNA clones were able to reveal RFLP patterns with varying degrees of polymorphism depending on the restriction enzymes used in the digestion of genomic DNAs. Although both probes could generate complex RFLP band patterns, those revealed by pB0S2 were generally easier to analyse and more suitable for DNA fingerprinting while those revealed by pRR566 were less distinct as a result of extensive background hybridisations. The probe pRR566, with certain restriction enzymes generated simpler RFLP band patterns that were more suitable for segregation analyses. Segregation analysis of F(_1) individuals revealed additive RFLP band patterns of both parental varieties, while that of F(_2) individuals revealed RFLP band patterns of each parental varieties as well as the additive pattern. When analysed for possible association with varietal glucosinolate content, none of the RFLP band patterns showed such linkage. A cDNA library was constructed from pod material of a high glucosinolate variety in an attempt to obtain clones which could reveal RFLP patterns associated with glucosinolate content. Differential screening using total cDNAs from pod materials of high and low glucosinolate varieties failed to isolate any cDNA clones useful as RFLP markers. Another DNA polymorphism assay studied, RAPD, was able to detect inter- and intraspecific variation in Brassica sp. Analysis of six phylogenetically-related but distinct Brassica sp. revealed extensive variation in the RAPD band patternsof amplification products; with some amphidiploid species sharing conserved band patterns with their ancestral species. RAPD analysis on 17 varieties of rape revealed polymorphic as well as highly conserved RAPD band patterns depending on the primer used. One of the primers was able to amplify a polymorphic band which could be associated with low glucosinolate varieties i.e. present almost exclusively in low glucosinolate varieties. Species-specific as well as variety-specific band patterns were also observed during the RAPD analysis. Finally, sequence and organisation of a Hind III family of repetitive sequences was studied. The monomeric and polymeric forms (trimer and tetramer) of the repetitive sequences were successfully cloned into pUCl8. Sequence analysis of the two clones containing the polymeric forms revealed that the monomers were arranged in tandem array and that all internal Hind III recognition sites were lost due to point mutation(s) which occurred within the six basepair recognition site. A consensus monomeric sequence was deduced from sequence comparison of the 8 copies of the monomeric sequences present in the 3 clones and the deviation from the consensus sequence of each of the eight monomers was less than 3%. No two monomeric sequences were identical. It was estimated that the number of copies of the monomeric sequences in a haploid genome was approximately 0.3 million copies. Estimates of the proportional representation of each of the polymeric sequences based on the number of copies of the monomers in each polymer were also calculated.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The plant metabolite, strigolactone, has recently gained the status of phytohormone as the result of several studies that implicated its role in plant architecture. These studies would characteristically rely on the use of mutants, such as the rms lines that were generated in peas, that shared several characteristics. This method allowed for the identification of several genetic component of the shared pathway. It is now known that the biosynthesis of strigolactone is dependent on the sequential action of an isomerase (D27) and two carotenoid cleavage deoxygenases (CCD7 and CCD8). Furthermore, it is known that strigolactone perception is localised to the plant nucleus, where it interacts with an α/β-fold hydrolase (D14) which would concomitantly binds to target proteins. The F box protein (MAX2) is able to recognize this proteïen complex. Through a MAX2 dependent mechanism the target protein becomes tagged for proteolysis. However, this model, though intricate, has only really been shown in higher plants. The model bryophyte, Physcomitrella patens, serves as a useful tool in genetic studies due to its predisposition for homologous recombination. More recently it has also gained interest in studies pertaining to strigolactones, which has led to the generation of a Ppccd8Δ mutant. Compared to the wild type, the Ppccd8Δ line produces more protonemal tissue. Furthermore, exogenous strigolactones have also been shown to inhibit colony expansion. Here we shown that there is only a single candidate gene, PpMAX2, present in the P. patens genome that could serve as a homologue for the Arabidopsis thaliana MAX2. Furthermore, we show that a recombinant GFP:PpMAX2 localises to the nucleus of P. patens cells. A Ppmax2:: mutant was generated which, unexpectedly, did not show the phenotype of Ppccd8Δ. Ppmax2:: has an apparent inability to produce protonema and appears to rather dedicate its growth to the production of gametophores. A double mutant, Ppccd8Δ max2Δ was generated which also displayed the characteristic phenotype of Ppmax2::. It seems therefore that the activity of PpMAX2 is able to override that of PpCCD8. By employing a GUS reporter system, we showed that the promoter, PPpMAX2, is predominantly active within gametophore tissues. Taken together, these results suggest that the activity of PpMAX2 facilitates the transition of gametophore tissue to protonema tissue. Although exogenous strigolactones did not appear to affect the growth of the Ppmax2:: line as it did the PpWT or Ppccd8Δ lines, those responses that have been ascribed to strigolactones to date have mostly been observed in protonemal tissue. We therefore suspect that any strigolactone response that might have been elicited in Ppmax2:: would have been masked by its phenotype of predominantly protonemal tissue. We are therefore hesitant to make any sweeping statements in regards to the role PpMAX2 might have in strigolactone perception in P. patens. However, though we suspect that PpMAX2 might not be a true functional homologue for the characterised MAX2 homologues from higher plants, we suspect that it may well be the ancestral predecessor of MAX2. / AFRIKAANSE OPSOMMING: Strigolaktoon is ‘n metaboliet wat deur plante vervaardig word en is redelik onlangs as ’n fitohormoon geklassifiseer. Die klassifikasie as fitohormoon is die gevolg van verskeie studies wat strigolaktoon se rol in die plantstruktuur beklemtoon het. In hierdie studie is daar gebruik gemaak van mutante, soos onderandere die rms lyne, wat gegenereer is in ertjies, wat verskeie kenmerke deel. Sodoende is verskeie komponente van ’n gedeelde molekulêre padweg geïdentifiseer. Daar word tans verstaan dat die sintese van strigolaktoon afhanklik is van die stapsgewyse aksies van ’n isomerase (D27) en twee karotenoïedklewingsdeoksigenases (CCD7 en CCD8). Verder is dit bekend dat strigolaktoon waargeneem word in die plant nukleus deur te assosieer met ’n α/β-vou-hidrolase (D14) wat vervolgens met teikenproteïene bind. Die kompleks word deur ’n F-boks proteïen (MAX2) herken wat daartoe lei dat die teikenproteïen gemerk word vir proteolise; altans, dit is tans die model wat vir hoër plante aanvaar word. Die model briofiet, Physcomitrella patens, word dikwels aangewend in genetiese studies weens dit ’n hoër vatbaarheid vir homoloë rekombinasie het. Om P. patens te benut in navorsing wat die rol van strigolaktoon ondersoek is ook voordelig, aangesien daar reeds ’n Ppccd8Δ mutant beskikbaar is. In vergelyking met die wilde tipe, produseer Ppccd8Δ meer protonemale weefsel en blyk dit dat strigolaktoon die vermoë het om kolonie verspreiding te bekamp. Hier wys ons dat daar ’n enkele kandidaat geen, PpMAX2, in die genoom van die P. patens teenwoordig is wat as ’n homoloog vir die Arabidopsis thaliana MAX2 kan dien. Verder wys ons dat ’n rekombinante GFP:PpMAX2 proteïen wel na die selkern van P. patens selle lokaliseer. ’n Ppmax2:: mutant is gegenereer wat, onverwags, nie die fenotipe van Ppccd8Δ vertoon het nie. Ppmax2:: het ’n onvermoë om protonema te produseer en wy groei eerder aan die produksie van gametofiete. ’n Dubbele mutant, Ppccd8Δ max2Δ, is gegenereer wat ook die fenotipe van Ppmax2:: vertoon het; dus kom ons tot die gevolgtrekking dat die aktiwiteit van PpMAX2 dié van PpCCD8 oorheers. Deur gebruik te maak van ’n GUS verklikkersisteem kon ons aflei dat die aktiwiteit van die PPpMAX2 promotor hoofsaaklik tot die uitdrukking van PpMAX2 in gametofiet weefsel lei. Dit is moontlik dat die aktiwiteit PpMAX2 dus die oorgang van gametofoor weefsel na protonema weefsel te weg bring. Alhoewel strigolaktoon nie die groei van die Ppmax2:: lyn beïnvloed soos vir die PpWT of Ppccd8Δ lyne nie, vermoed ons dat die reaksie slegs in die protonemale weefsel waargeneem sal word. Daar kan tans nie met absolute sekerheid gesê word of PpMAX2 enigsins verbonde met strigolaktoon persepsie in mos is nie, tog vermoed ons dat PpMAX2 ’n primitiewe voorloper vir die gekarakteriseerde MAX2 homoloë van die hoër plante is.

Tutaméia Terceiras Estórias é a obra de Guimarães Rosa que mais dá mostras da preocupação do escritor com a materialidade do livro e com os processos de apreensão da leitura. O recurso mais explorado para isso foi o uso excessivo do paratexto, que inscreve um espaço intermediário entre o livro e o leitor, sugerindo a ele que reflita sobre o tempo da produção literária. Seguindo essas pistas sobre a prática da escrita, propomos neste estudo a reflexão sobre os procedimentos de composição do manuscrito literário e seu espelhamento em problemas narrativos propostos ao leitor nos textos Desenredo e Sobre a escova e a dúvida. / Terceiras Estórias is the one of Guimarães Rosas works that shows his preoccupation with the materiality of the book and about its reception. To achieve this goal he explored textual elements that create intermediary spaces between the book and the reader, leading the latter to consider the time of the books production. Following clues about Rosas practice of writing, we intend to consider the composition of the literary manuscript and its reflection on the narrative problems proposed to the reader in the texts Desenredo and Sobre a escova e a dúvida.

Schizophrenia is one of the most severe mental disorders. Heredity is accepted as a major causative factor. To find molecular mechanisms behind schizophrenia, patient materials with reliable and valid diagnoses must be identified. In order to compare schizophrenia diagnostic procedures for reliability, validity and suitability for genetic studies by evaluation of record information, interview and register diagnostic data and to examine patient materials for linkage or association with molecular genetic markers three patient materials were recruited: sporadic cases, a large pedigree and sib-pairs. Schizophrenia diagnoses based on patient records only, showed good to excellent agreement with diagnoses based on both records and interviews. Register diagnoses generally displayed poor agreement with research diagnoses, but in 94% of patients sometimes registered as schizophrenic psychoses a research diagnosis of these disorders was certified. In the pedigree, analysis suggested linkage to chr 6p23 in a single branch of the pedigree, and a genome scan indicated linkage to the 6q25 region. A genome scan analysis of the sib-pair material was suggestive of linkage to chr 10q25.3-q26.3. In the case-control sample and a meta-analysis there was an association between a dopamine D2 receptor polymorphism (Ser311Cys), on chr 11q22-23, and the disorder. Brain-derived neurotrophic factor gene variants (chr 11p13) were also analysed without any robust significant findings. For patients in long-term treatment for schizophrenia in Sweden, psychiatric record reviews should be valid, reliable and sufficient for assessment of lifetime research diagnosis. Swedish register diagnosis of schizophrenic psychoses has a high positive predictive power in relation to corresponding research diagnoses. For future Swedish studies focusing on a broad definition of schizophrenia, it is sufficient to rely on the register diagnoses of schizophrenic psychosis. There is no major vulnerability gene or locus that is common to the majority of patients with schizophrenia, indicating genetic heterogeneity.

Tutaméia Terceiras Estórias é a obra de Guimarães Rosa que mais dá mostras da preocupação do escritor com a materialidade do livro e com os processos de apreensão da leitura. O recurso mais explorado para isso foi o uso excessivo do paratexto, que inscreve um espaço intermediário entre o livro e o leitor, sugerindo a ele que reflita sobre o tempo da produção literária. Seguindo essas pistas sobre a prática da escrita, propomos neste estudo a reflexão sobre os procedimentos de composição do manuscrito literário e seu espelhamento em problemas narrativos propostos ao leitor nos textos Desenredo e Sobre a escova e a dúvida. / Terceiras Estórias is the one of Guimarães Rosas works that shows his preoccupation with the materiality of the book and about its reception. To achieve this goal he explored textual elements that create intermediary spaces between the book and the reader, leading the latter to consider the time of the books production. Following clues about Rosas practice of writing, we intend to consider the composition of the literary manuscript and its reflection on the narrative problems proposed to the reader in the texts Desenredo and Sobre a escova e a dúvida.

La thèse est une étude génétique des œuvres de l’écrivain sicilien Gesualdo Bufalino (1920-1996). À travers l’analyse du processus d’écriture, ce travail reconstruit la genèse des toutes les œuvres terminées par Bufalino pendant sa jeunesse et jusqu’à son exorde, en 1981, avec le roman Diceria dell’untore. Les sondages effectués dans les archives conservant les matériaux génétiques de Bufalino nous a permis d’anticiper la phase créative de Bufalino aux années 1955-65. Nous avons notamment identifié dans un roman inédit, Il guazzabuglio, qui remonte à 1977, une sorte de canevas où de réservoir, d’où l’écrivain tira des thèmes ou des séquences narratives pour d’autres œuvres. Ce roman toujours considéré comme inachevé non seulement fut complété par Bufalino, mais il fut aussi étroitement lié à la genèse des deux premiers romans, Diceria dell’untore (1981) et Argo il cieco (1984), d’une part, et avec Qui pro quo (1991) et Tommaso e il fotografo cieco (1996), le dernier roman de Bufalino qui peut être considéré́ comme sa réécriture. Les œuvres achevées et publies de 1981 jusqu’à sa mort, en 1996, ont été le résultat d’un processus créatif commencé pendant sa jeunesse et poursuivi pendant tout sa vie. La reconstruction de la genèse des ouvrages rédigés avant 1981, est accompagnée de la reconstruction de la biographie intellectuelle de Bufalino à travers l’étude des sources et documents d’archive. / The thesis is a genetic study of the works of the Sicilian writer Gesualdo Bufalino (1920-1996). Through the analysis of the writing process, this study reconstructs the genesis of all the works completed by Bufalino during his youth and up until his debut in 1981, with the novel Diceria dell'untore. The research carried out in the archives which hold the genetic materials of Bufalino enabled us to date the creative phase of Bufalino in the period 1955-65. In particular, we have identified in an unpublished novel, Il guazzabuglio, dating back to 1977, a kind of canvas or reservoir, from which the writer drew themes or narrative sequences for other works. This novel, still considered unfinished, was not only completed by Bufalino, but was also closely linked to the genesis of the first two novels, Diceria dell'untore (1981) and Argo il cieco (1984), on the one hand, and to Qui pro quo (1991 and Tommaso e il fotografo cieco (1996), Bufalino’s last novel which can be considered its rewriting. The works completed and published from 1981 until his death in 1996, were the result of a creative process begun during his youth and continued throughout his life. The reconstruction of the genesis of the works written before 1981 is accompanied by the reconstruction of the intellectual biography of Bufalino through the investigation of sources and archive documents.

Introduction: Type 2 diabetes mellitus (T2DM) is a worldwide spread disease of affluence which prevalence has been growing. Although, the probability of its manifestation is being linked above all with environmental factors, genetic susceptibility plays an important role too. The aim of this thesis was to find out the association of four polymorphisms with the risk of T2DM manifestation in Czech population. Polymorphisms rs10203174 THADA, rs6819243 MAEA, rs849135 JAZF1 and rs1552224 ARAP1 (CENTD2) were chosen based on their risk in British population. Methodology: We studied groups of 712 Czech patients with T2DM and 752 healthy controls selected as a random sample of Czech population in the post-MONICA study. For a genotypisation rs10203174 and rs6819243 we used the PCR-RFLP method. For an analysis of genotypes rs849135 and rs1552224 was used the real-time PCR method. The results were analysed via odds ratio (OR) a chi-square test. Results: In case of the rs1552224 variant, the risk was proved with statistical significance (P = 0,01). The value of OR for the risk allele T is 1,37 (95% CI 1,07-1,75). In case of the polymorphisms rs10203174, rs6819243 and rs849135 no significant association with the disease was proved. For rs10203174 the value of OR of the allele C is 1,20 (95% CI 0,91-1,56, P = 0,20), OR of...