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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.
81

Supervisão de supervisão: grande angular fenomenológica na cartografia de práticas clínicas em contextos institucionais e comunitários / Supervision of supervision: a phenomenological upward look toward the cartography of clinical practices at the institutional and community contexts

Tatiana Benevides Magalhães Braga 24 September 2010 (has links)
Esta pesquisa investigou a prática clínica de Supervisão de Supervisão, espaço de discussão entre supervisores clínicos de diferentes projetos de atenção psicológica em instituições e comunidades. Utilizando uma abordagem fenomenológica, a investigação se baseou numa cartografia clínica desta prática, abrangendo a historicidade de sua constituição e o contexto no qual se mostra seu desenrolar, apresentado em cenas de supervisão de supervisão relativas a diferentes cenários sociais em que se desenvolveram modalidades de prática psicológica. O diálogo dos supervisores desvelou alguns eixos teóricos de discussão atinentes à práxis desenvolvida, que foram abordados por meio de ensaios, buscando dialogar com o modo como tais temas emergentes foram apresentados nas supervisões de supervisão e refletir sobre seu sentido. O primeiro eixo abordado foi a cartografia, em relação à qual se buscou contemplar aproximações e diferenças entre a prática realizada e outros autores que discutem o tema, em especial aqueles utilizados como referência pelos supervisores na compreensão de suas práticas, delineando-se uma cartografia clínica de orientação fenomenológica. O segundo tema apresentado refere-se às relações entre psicologia e fenomenologia, quanto ao qual o ensaio procura demonstrar a pertinência do olhar fenomenológico na psicologia a partir da historicidade destes campos. Em relação ao terceiro eixo temático a práxis psicológica realizada nos contextos institucionais e comunitários o ensaio aborda duas vertentes interligadas. Discute-se, por um lado, a origem de um entrelaçamento entre sujeito e contexto social a partir das interdisciplinaridades, pluridisciplinaridades e transdisciplinaridades originadas no questionamento do papel da ciência e da universidade a partir do pós-guerra. Por outro lado, o ensaio trata da inserção da clínica em cenários externos ao consultório particular enquanto articulada à falência do modelo de clínica liberal e aos movimentos políticos pela construção de direitos de cidadania, no panorama brasileiro ocorridos em especial na saúde pública e na saúde mental. No tocante ao quarto tema, o lugar do aconselhamento psicológico a partir da fenomenologia existencial, o ensaio versa sobre a compreensão da atenção psicológica como possibilidade de designação pertinente à práxis, abrangendo o olhar sobre a experiência enquanto modo de habitar o mundo. Finalmente, quanto ao quinto tema, as relações entre clínica e política são discutidas no intuito de designar o espaço clínico enquanto pré-político. A partir destas discussões, a supervisão de supervisão é compreendida como uma grande angular, em que se interpenetram cinco dimensões: investigativo-cartográfica (relacionada à compreensão/interpretação dos espaços internos e externos em que ocorre a prática), prático-teórica (movimento de compreensão da experiência e sua interpretação pela palavra), clínica (diálogo que permite o entrelaçamento de significações e experiências), pedagógica (a aprendizagem que se realiza no nomear a experiência, na atribuição de sentido, na multiplicação dos sentidos possíveis e na compreensão do processo de aprendizagem clínica) e ético-política (na construção de referenciais a partir dos quais é possível compreender o mundo e agir sobre ele) / This work intended to investigate Supervision of Supervision as a clinical practice for discussion between clinical supervisors from psychological attention institutions and communities different projects. By using a existential phenomenological approach, the investigation was based upon a clinical cartography that shows the history of its constitution and contexts where it happens: Supervision of Supervisions different scenes concerning to different social scenarios where the psychological practice took place. The supervisors conversation allowed disclosing five theoretical axes for reflexions about the praxis. Such axes were explored by essays that dialogue with the mode by which they were presented at the supervisions. The first axe presents the cartography, relating it to the practice developed and some thoughts by authors reffered by the supervisors to comprehend their action in supervision: a clinical cartography in a existential phenomenological perspective was revealed. The second theme refers to relations between psychology and phenomenology, to demonstrate the property of the phenomenological optics for psychology when the historicity of those practical fields is taken into account. The third axe deals with the psychological practice in institutional and communitarian contexts, approaching to interconnected trends. By one side, it discusses the original interconnection between subject and social context, concerning interdisciplinary, multidisciplinary and transdisciplinary and their post-war role as in science as at the university. On the other hand, the third essay deals with the clinics insertion in scenarios, others than the traditional private practice, model inspired by the Brazilian political liberal movements for citizens rights specially for Public Health and Mental Health. Yet, the fourth axe explores counseling psychology by the existential phenomenology, in respect to the comprehension of psychological attention as a proper designation for that kind of praxis, encompassing experience as a human mode to dwell in the world. Finally, the fifth theme discusses the relations between clinic and politics in other to designate the clinical context as pre-political. The conclusion points to supervision of supervision as a great angular lens, where five dimensions interrelate themselves: the investigative-cartographic one (comprehension/interpretation of internal and external practice spaces); the practicaltheoretical one (movement for experience comprehension and interpretation by the speech); the clinical one (dialogue that propitiates interrelations between experience and meaning); the pedagogic one (learning by sense attribution while nominating experience, expanding possible meanings to the clinical learning); and the ethical-political dimension (referential construction that provides the comprehension of the world and to act upon it)
82

A instabilidade genômica como fator prognóstico e diagnóstico na progressão de queratose actínica para carcinoma espinocelular humano / Genomic instability as a prognostic and diagnostic factor on the progression of human actinic keratosis, to squamous cell carcinoma

Luciana Sanches Cabral 19 June 2007 (has links)
A instabilidade genômica tem sido amplamente usada para caracterizar células cancerosas. Alterações genéticas em queratose actínica (QA) e carcinoma espinocelular (CEC) foram investigadas pelo método de random amplified polymorphic DNA (RAPD) e análise de microssatélites com o objetivo de encontrar marcadores moleculares para auxiliar o prognóstico e o diagnóstico médico. O DNA foi obtido de pacientes brasileiros cirurgiados e tratados no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, totalizando oito QAs, 24 CECs, e tecidos normais e/ou leucócitos correspondentes. Os microssatélites estudados foram D6S251, D6S252, D9S15, D9S50, D9S52, D9S180, D9S196, D9S280 e D9S287, tendo em vista a detecção de instabilidade genômica representada por perda de heterozigosidade (LOH) e instabilidade de microssatélites (MSI). Os \"primers\" usados para comparar os padrões de RAPD foram OPA-2, OPA-7, OPA-13, OPA-17, OPB-8, OPB-13, OPB-17 e OPB-19. Foi obtida correlação significativa na progressão de QA (1/8) para CEC (5/22) referente ao microssatélite D6S251. As diferenças nos padrões de DNA obtidos pelo método RAPD comparados aos controles foram maiores em lesões com maior grau de severidade segundo critério histológico. O mesmo padrão RAPD foi observado no controle e no tumor em 27% QA, 24% CEC I, 9% CEC II e 0% CEC III. Estes resultados mostram que o microssatélite D6S251 e o método de RAPD são informativos, podendo ser potenciais candidatos para auxílio no diagnóstico e prognóstico de QA e CEC. / Genomic instability has been widely used to characterize cancer cells. Genetic alterations in human actinic keratosis (AK) and squamous cell carcinomas (SCC) were investigated by the random amplified polymorphic DNA (RAPD) method, and microsatellite analysis. DNA was obtained from Brazilian patients diagnosed and treated in the School of Medicine of University of Sao Paulo out Clinics Hospital. Eight AKs, 24 SCCs, and 4 BCCs, matched to normal skin tissue and/or leukocytes were studied. Microsatellite patterns were obtained with primers specific to amplify D6S251, D6S252, D9S15, D9S50, D9S52, D9S180, D9S196, D9S280, and D9S287, in search of detection Loss of heterozygosity (LOH) and Microsatellite instability (MSI). The RAPD primers were: OPA-2, OPA-7, OPA-13, OPA-17, OPB-8, OPB-13, OPB-17, and OPB-19. A significant correlation was obtained regarding the progress of AK (1/8) to SCC (5/22) detected with the D6S251 microsatellite. DNA fingerprint obtained with RAPD primers were altered in increasing number of samples, according to their histological degree of differentiation. Similar RAPD patterns were observed in tumor and control in 27% AK, 24% SCC I, 9% SCC II, and zero SCC III. These results suggest microsatellite D6S251 and RAPD method to be potential tools in diagnosis and prognosis of AK and SCC.
83

Diversity of a disease resistance gene homolog in Andropogon gerardii (poaceae) is correlated with precipitation

Rouse, Matthew January 1900 (has links)
Master of Science / Department of Plant Pathology / Karen A. Garrett / Ecological clines often result in gradients of disease pressure in natural plant communities, imposing a gradient of selection on disease resistance genes. We describe the diversity of a resistance gene homolog in natural populations of the dominant tallgrass prairie grass, Andropogon gerardii, across a precipitation gradient ranging from 47.63 cm/year in western Kansas to 104.7 cm/year in central Missouri. Since moisture facilitates infection by foliar bacterial pathogens, plants along this precipitation gradient will tend to experience heavier bacterial disease pressure to the east. In maize, the gene Rxo1 confers resistance to the pathogenic bacterium Burkholderia andropogonis. Rxo1 homologs have been identified in A. gerardii and B. andropogonis is known to infect natural populations of A. gerardii. The spatial genetic structure of A. gerardii was assessed from central Missouri to western Kansas by genotyping with AFLP markers. Samples were also genotyped for Rxo1 homologs by amplifying an 810 base pair region of the leucine-rich repeat and digesting with restriction enzymes. We compared Rxo1 homolog diversity to AFLP diversity across different spatial scales. Genetic dissimilarity based on AFLP markers was lower than would have occurred by chance at distances up to 30 m, and different prairies were more dissimilar than would have occurred by chance, but there was not a longitudinal trend in within-prairie dissimilarity as measured by AFLP markers. Dissimilarity of the Rxo1 homologs was higher in the east suggesting the presence of diversifying selection in the more disease-conducive eastern environments.
84

Organické pevnolátkové lasery / Organic solid state lasers

Koutný, Jan January 2013 (has links)
The aim of this thesis is the preparation and characterization of model components for organic thin-film solid-state lasers. The theses focuses on comparing different methods of determining the threshold energy, which leads to an amplified spontaneous emission of the studied derivative diketo-pyrrolo-pyrrole. The theoretical part is devoted to a summary of knowledge on the interaction of light with matter and lasers with a focus on organic solid-state lasers. The practical part is focused on preparation of model components for organic solid-state lasers, modification of apparatus for their characterization, comparison of evaluation methods for determining the threshold energy and study of the effect of different conditions of components preparation.
85

Amplified Total Internal Reflection at the Surface of Gain Medium

Orndorff, Josh 22 August 2013 (has links)
No description available.
86

Sequentielle Genotypisierung von Pseudomonas aeruginosa-Isolaten und Übereinstimmung von bakteriologischen Proben aus dem oberen und unteren Respirationstrakt von Patienten mit cystischer Fibrose

Jung, Andreas 26 October 2005 (has links)
Die Frage nach adäquaten mikrobiologischen und molekulargenetischen Methoden, um die Kolonisation des Respirationstrakts von Mukoviszidose-Patienten mit Pseudomonas aeruginosa nachzuweisen und zu charakterisieren, wird kontrovers diskutiert. Von 38 klinisch stabilen Patienten mit cystischer Fibrose (CF) wurden sequentiell im Abstand von 18 Monaten Proben aus Rachenabstrich, Sputum und Bronchiallavage (BAL) entnommen und bezüglich Pseudomonas-Nachweis untersucht. Die Pseudomonas-Stämme wurden mittels Random Amplified Polymorphic DNA (RAPD)-Analyse und Pulsfeld-Gelelektrophorese (PFGE) von DNA-Makrorestriktionsfragmenten typisiert und bezüglich der Frage nach genetisch divergierenden Isolaten innerhalb des selben Individuums sowie nach möglichen longitudinalen genetischen Veränderungen evaluiert. Sensitivität, negative und positive prädiktive Werte und Spezifität, um eine P. aeruginosa-Besiedlung zu erkennen, waren 36%, 74%, 83% und 96% im Falle der Kulturen aus dem Oropharynx von nicht-expektorierenden Patienten und 92%, 94%, 100% und 100% für Sputumkulturen von expektorierenden Probanden. RAPD-Analyse und PFGE waren in der Lage, zwischen unterschiedlichen Pseudomonas-Stämmen zu diskriminieren, wobei nur die DNA-Makrorestriktion zwischen Subtypen unterscheiden konnte. Die Genotypen der Pseudomonas-Isolate aus Rachenabstrich und Sputum divergierten in 55% und 40% zu den Isolaten der BAL. Longitudinale Variationen des Genotyps wurden in 62% der Fälle beobachtet, die Hälfte davon war nur mittels bronchoskopisch gewonnener Proben erkennbar. Zusammengefasst besitzen Sputumproben bezüglich des Pseudomonas-Nachweises dieselbe Wertigkeit wie Kulturen aus der BAL, während Rachenabstriche in einer frühen Krankheitsphase für die Charakterisierung der bakteriellen Flora des unteren Respirationstrakts wenig geeignet sind. Die Methode der DNA-Makrorestriktion kann als zuverlässige Technik für epidemiologische Untersuchungen empfohlen werden. Unterschiedliche Genotypen innerhalb desselben Individuums und longitudinale genetische Alterationen sind häufig, jedoch unter Umständen nur bronchoskopisch nachweisbar. / There is controversy about adequate specimen to detect and characterise colonisation of cystic fibrosis (CF) airways by Pseudomonas aeruginosa. Oropharyngeal, sputum and bronchoalveolar lavage (BAL) samples were evaluated sequentially from 38 stable CF patients for the detection of P. aeruginosa. Pseudomonas strains were typed by random amplified polymorphic DNA (RAPD) analysis and pulsed-field gel electrophoresis (PFGE) of DNA macrorestriction fragments. The occurrence of genetically different isolates within the same host and longitudinal variations in the genotype during repeated examinations was assessed. Sensitivity, negative and positive predictive values and specificity to detect P. aeruginosa were 36%, 74%, 83% and 96% for oropharyngeal cultures in non-expectorating patients and 92%, 94%, 100% and 100% for sputum cultures from expectorating patients, respectively. RAPD analysis and PFGE were suitable to characterize P. aeruginosa CF isolates, although only DNA macrorestriction was able to distinguish between identical and closely related strains. Genotypes of Pseudomonas isolates recovered from oropharyngeal swabs and sputum differed to the strains recovered by bronchoscopy in 55% and 40%, respectively. In 62% longitudinal variations in the genotype occurred. Half of these alterations were only detectable from bronchoscopically obtained samples. In conclusion, sputum samples have the same value as specimens from BAL to detect P. aeruginosa colonisation, whereas cultures from the oropharynx are not suitable for characterising the bacterial conditions in the CF lungs in an early disease state. DNA macrorestriction is recommended as an excellent tool for epidemiological investigations. Different genotypes within the same host and longitudinal genetic alterations are common and may be detectable in the BAL fluid exclusively.
87

Molecular authentication of endangered reptiles for Chinese medicinal materials.

January 2001 (has links)
Wong Ka Lok. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 121-129). / Abstracts in English and Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / Table A --- p.v / Table B --- p.vi / Table of Contents --- p.vii / Abbreviations --- p.xi / Chapter Chapter 1 --- Molecular authentication of endangered crocodiles and snakes / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Traditional method of snake and crocodile identification / Chapter 1.2.1 --- Morphology --- p.7 / Chapter 1.2.2 --- Chemical Analysis --- p.9 / Chapter 1.3 --- Molecular Technology in Authentication / Chapter 1.3.1 --- Polymerase Chain Reactions (PCRs) --- p.11 / Chapter 1.3.2 --- Random-primed amplification reaction --- p.12 / Chapter 1.3.3 --- Sequence Characterized Amplified Region (SCAR) --- p.13 / Chapter 1.3.4 --- PCR-RFLP --- p.13 / Chapter 1.3.5 --- DNA sequencing --- p.14 / Chapter 1.4 --- Objectives and strategies of the study --- p.15 / Chapter Chapter 2 --- Materials and General Methods / Chapter 2.1 --- Reagents and Buffers / Chapter 2.1.1 --- Buffers for Total DNA Extraction --- p.17 / Chapter 2.1.2 --- Reagents for Agarose Gel Electrophoresis --- p.17 / Chapter 2.1.3 --- Reagents for Plasmid DNA Preparation --- p.18 / Chapter 2.1.4 --- Medium for Bacterial Culture --- p.18 / Chapter 2.1.5 --- Reagents for Preparation of Competent Cells --- p.19 / Chapter 2.2 --- DNA Isolation / Chapter 2.2.1 --- Extraction of DNA from meats --- p.20 / Chapter 2.2.2 --- Extraction of DNA from blood --- p.20 / Chapter 2.3 --- Phenol/Chloroform Extraction --- p.21 / Chapter 2.4 --- Ethanol Precipitation --- p.22 / Chapter 2.5 --- DNA Concentration/Purity Estimation --- p.22 / Chapter 2.6 --- Mitochondrial DNA amplification --- p.23 / Chapter 2.7 --- Random-Primed Polymerase Chain Reactions --- p.24 / Chapter 2.8 --- SCAR for Snake samples --- p.24 / Chapter 2.9 --- SCAR for Crocodile samples --- p.25 / Chapter 2.10 --- Restriction fragment length polymorphism analysis --- p.25 / Chapter 2.11 --- Agarose Gel Electrophoresis of DNA --- p.26 / Chapter 2.12 --- Purification of PCR product --- p.26 / Chapter 2.13 --- Preparation of Escherichia coli Competent Cells --- p.27 / Chapter 2.14 --- Ligation and transformation of E. coli --- p.27 / Chapter 2.15 --- Plasmid preparation --- p.28 / Chapter 2.16 --- Screening of Plasmid DNA by Restriction Digestion --- p.29 / Chapter Chapter 3 --- DNA sequencing of snakes & construction of snake database / Chapter 3.1 --- Introduction --- p.30 / Chapter 3.2 --- Materials and methods / Chapter 3.2.1 --- Snake samples --- p.32 / Chapter 3.2.2 --- "DNA Extraction, mitochondrial gene amplification and DNA sequencing" --- p.33 / Chapter 3.2.3 --- Construction of database --- p.33 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Cytochrome b gene amplification and sequencing --- p.34 / Chapter 3.3.2 --- Gene amplification and sequencing of 16S rRNA --- p.42 / Chapter 3.3.3 --- Cytochrome b sequence database --- p.50 / Chapter 3.3.4 --- 16S rRNA sequence database --- p.53 / Chapter 3.4 --- Discussion / Chapter 3.4.1 --- Cytochrome b and 16S rRNA genes of snake species --- p.55 / Chapter 3.4.2 --- Cytochrome b and 16S rRNA databases --- p.55 / Chapter Chapter 4 --- Application of PCR-RFLP and SCAR in snake species identification / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- Material and Methods / Chapter 4.2.1 --- DNA extraction and PCR-RFLP --- p.58 / Chapter 4.2.2 --- RAPD and SCAR --- p.58 / Chapter 4.3 --- Results / Chapter 4.3.1 --- PCR-RFLP of cytochrome b genes of snakes --- p.59 / Chapter 4.3.2 --- PCR-RFLP of 16S rDNA --- p.61 / Chapter 4.3.3 --- RAPD & SCAR analysis --- p.67 / Chapter 4.4 --- Discussion --- p.72 / Chapter Chapter 5 --- "Application of DNA sequencing, PCR-RFLP and SCAR to identify crocodile species" / Chapter 5.1 --- Introduction --- p.74 / Chapter 5.2 --- Materials and methods / Chapter 5.2.1 --- "Crocodile, human and four animal samples" --- p.75 / Chapter 5.2.2 --- "DNA Extraction, mitochondrial gene amplification and DNA sequencing" --- p.75 / Chapter 5.2.3 --- PCR-RFLP and SCAR --- p.76 / Chapter 5.3 --- Results / Chapter 5.3.1 --- Isolation of crocodiles DNA --- p.77 / Chapter 5.3.2 --- Isolation of DNA from Human and four animal species --- p.78 / Chapter 5.3.3 --- Cytochrome b gene amplification and sequencing --- p.78 / Chapter 5.3.4 --- 16S rRNA gene amplification and sequencing --- p.84 / Chapter 5.3.5 --- PCR-RFLP of cytochrome b --- p.89 / Chapter 5.3.6 --- PCR-RFLP of 16S rRNA --- p.91 / Chapter 5.3.7 --- SCAR primers for four crocodile species --- p.93 / Chapter 5.4 --- Discussion --- p.97 / Chapter Chapter 6 --- A case report - authentication of animal samples using DNA sequencing / Chapter 6.1 --- Introduction --- p.99 / Chapter 6.2 --- Material and methods / Chapter 6.2.1 --- Materials --- p.101 / Chapter 6.2.2 --- DNA Extraction and sequencing --- p.101 / Chapter 6.3 --- Result and discussion / Chapter 6.3.1 --- Cytochrome b gene sequencing --- p.102 / Chapter 6.3.2 --- Sequence homology among samples and meats obtained from the market --- p.111 / Chapter 6.3.3 --- Identity of samples B & D --- p.113 / Chapter Chapter 7 --- General Discussion / Chapter 7.1 --- Advantages and weakness of DNA technology --- p.116 / Chapter 7.2 --- Choosing appropriate molecular markers --- p.118 / Chapter 7.3 --- Further suggested work --- p.119 / Chapter 7.4 --- Conclusion --- p.119 / References --- p.121 / Appendix --- p.130
88

Protoplast fusion of Lolium perenne and Lotus corniculatus for gene introgression

Raikar, Sanjeev Vencu January 2007 (has links)
Protoplast fusion of Lolium perenne and Lotus corniculatus for gene introgression by Sanjeev V. Raikar Lolium perenne is one of the most important forage crops globally and in New Zealand. Lotus corniculatus is a dicotyledonous forage that contains valuable traits such as high levels of condensed tannins, increased digestibility, and high nitrogen fixing abilities. However, conventional breeding between these two forage crops is impossible due to their markedly different taxonomic origin. Protoplast fusion (somatic hybridisation) provides an opportunity for gene introgression between these two species. This thesis describes the somatic hybridisation, the regeneration and the molecular analysis of the putative somatic hybrid plants obtained between L. perenne and L. corniculatus. Callus and cell suspensions of different cultivars of L. perenne were established from immature embryos and plants were regenerated from the callus. Of the 10 cultivars screened, cultivars Bronsyn and Canon had the highest percentage of callus induction at 36% each on 5 mg/L 2,4-D. Removal of the palea and lemma which form the seed coat was found to increase callus induction ability of the embryos. Plant regeneration from the callus was achieved when the callus was plated on LS medium supplemented with plant growth regulators at different concentrations. Variable responses to shoot regeneration was observed between the different cultivars with the cv Kingston having the lowest frequency of shoot formation (12%). Different factors affecting the protoplast isolation of L. perenne were investigated. The highest protoplast yield of 10×106 g-1FW was obtained when cell suspensions were used as the tissue source, with enzyme combination ‘A’ (Cellulase Onozuka RS 2%, Macerozyme R-10 1%, Driselase 0.5%, Pectolyase 0.2%), for 6 h incubation period in 0.6 M mannitol. Development of microcolonies was only achieved when protoplasts were plated on nitrocellulose membrane with a L. perenne feeder layer on PEL medium. All the shoots regenerated from the protoplast-derived calli were albino shoots. The highest protoplast yield (7×106 g-1FW) of L. corniculatus was achieved from cotyledons also with enzyme combination ‘A’ (Cellulase Onozuka RS 2%, Macerozyme R-10 1%, Driselase 0.5%, Pectolyase 0.2%), for 6 h incubation period in 0.6 M mannitol. The highest plating efficiency for L. corniculatus of 1.57 % was achieved when protoplasts were plated on nitrocellulose membrane with a L. perenne feeder layer on PEL medium. The highest frequency of shoot regeneration (46%) was achieved when calli were plated on LS medium with NAA (0.1 mg/L) and BA (0.1 mg/L). Protoplast fusion between L. perenne and L. corniculatus was performed using the asymmetric somatic hybridisation technique using PEG as the fusogen. L. perenne protoplasts were treated with 0.1 mM IOA for 15 min and L. corniculatus protoplasts were treated with UV at 0.15 J/cm2 for 10 min. Various parameters affecting the fusion percentage were investigated. Successful fusions were obtained when the fusions were conducted on a plastic surface with 35% PEG (3350 MW) for 25 min duration, followed by 100 mM calcium chloride treatment for 25 min. A total of 14 putative fusion colonies were recovered. Shoots were regenerated from 8 fusion colonies. Unexpectedly, the regenerated putative hybrid plants resembled L. corniculatus plants. The flow cytometric profile of the putative somatic hybrids resembled that of L. corniculatus. Molecular analysis using SD-AFLP, SCARs and Lolium specific chloroplast microsatellite markers suggest that the putative somatic hybrids could be L. corniculatus escapes from the asymmetric protoplast fusion process. This thesis details a novel Whole Genome Amplification technique for plants using Strand Displacement Amplification technique.
89

Extracting Genomic Variations using Selector Technology

Isaksson, Magnus January 2010 (has links)
This thesis describes the development and use of a new class of molecular tools called Selector probes, and its potential for investigations of genetic variation. The Selector technology provides multiplex amplification of targeted DNA sequences with a high specificity, and an enrichment factor in the same order of magnitude as PCR. A common feature in this thesis work is to focus the analysis on DNA regions of interest. For example, this technique can be implemented in analysing candidate regions found by whole genome studies that need validation (global to local analysis), and applications requiring detection of rare alleles (common to rare allele), important in for example cancer samples. An assay is presented that allows for fast and simple quantification of relative copy-number variations. The method was proven to be able to detect aneuploidy in chromosome 13, 18, 21 and X, with a resolution enough to distinguish between 4 and 5 copies. The method was successfully applied to solve a biological question regarding a copy-number variation, that explains the Ridge phenotype typical for the dog bread Rhodesian Ridgebacks. The Selector strategy was able to detect and map a tandem duplication with a size of 133 kb, which was characterized with base-pair resolution. A readout platform that facilitates simultaneous digital quantitative analysis of a large numbers of biomolecules is further introduced. The work involves arraying amplified product from successful selection and decoding each molecule by hybridization of fluorophore labeled oligonucleotides. Finally, a genome partitioning method which is applied upstream of next generation sequencing platforms is presented. It is shown that the method provides successful enrichment with 98 % coverage and 94 % specificity and high enrichment uniformity. The technique was applied for mutation analysis of 26 cancer-related genes in tumor cell-lines and tissue.
90

Fingerprinting of full and half-sib black wattle (Acacia mearnsii) progenies using Random Amplified Polymorphic DNA (RAPD).

Naguran, Riann. January 2005 (has links)
Black wattle (Acacia mearnsii), which belongs to the genus Acacia, is one of the many species of trees or hardwoods grown commercially in South Africa. Black wattle is a species indigenous to Australia and was introduced into South Africa by the van der Plank brothers in 1864. These trees are grown in South Africa because of its tannin-rich bark, the extract of which is used by the leather tanning industry. Black wattle is also grown for its timber, timber products and pulp. The introduction and cultivation history of black wattle suggests that the South African plantations contain limited genetic variation with relatedness amongst groups estimated to be high, thus implying a narrow genetic base in the South African black wattle population. In this investigation, Random Amplified Polymorphic DNA (RAPD) was used to estimate the genetic variation between seven different black wattle groups. A total number of 34 individuals obtained from different areas in South Africa were examined; Piet Retief (group 47 and 50: half-sibs), Kumbula (group 85: unrelated individuals), Howick (group 400: unrelated individuals) and an unknown area (groups 88, 89, 91: full-sibs). As this investigation was the first of its kind, a DNA isolation method as well as a PCR-RAPD protocol had to be modified. Total genomic DNA was successfully extracted using the CTAB DNA extraction method. This method removed large amounts of tannin present in the cells of the black wattle leaves and extracted high quality DNA to conduct between 50-100 RAPD reactions. The DNA purities ranged from 0.1 to 1.8, with an average of 1.46. A total of fourteen 10-mer RAPD primer sequences were randomly selected from the Operon Technologies primer list A, and tested in this investigation. Of the 14 primers used, only nine primers produced clear, single and repeatable bands. Therefore nine primers were selected for subsequent analyses. Ninety one loci that generated bands ranging from 300-3050 base pairs were produced. Seven to 13 loci per primer were generated. A total of 95.6 % of the loci were polymorphic. The overall expected mean heterozygosity (H = 0.3) obtained in this study was high in comparison to other studies conducted on acacias. The high levels of genetic variation were attributed to mating systems, dissortative mating and geographic distribution. The statistical packages POPGENE and ARLEQUIN were used to analyse the RAPD fingerprints. The genetic measures, Nei's diversity and Shannon's Information Index, showed that there was greater diversity exhibited (Nei's gene diversity = 32.09 % and Shannon's = 48.31 %), in the whole population than in each of the groups (with average of Nei's gene diversity = 20.33 % and Shannon's = 34.64 %). With regards to individual group analyses, low levels of genetic variation was obtained in group 400 (unrelated), from the Howick region, and group 85 (unrelated), from the Kumbula region, (mean 0.14 and 0.17 respectively). The low genetic values were attributed to limited gene exchange occurring in these two areas, bottlenecks and selection pressures. Groups 88, 89 and 91, from the unknown region (full-sib groups), were the most variable in comparison to the other groups, with means of (0.27,0.24 and 0.18 respectively). These high genetic variation values could be due to the fact that gene migration could have occurred between these groups and others in the area. It is thought that most acacias are insect-pollinated and this could have lead to gene migration between groups or populations, thereby explaining the high mean values. The gene flow obtained for the seven groups (FST = 0.174) indicated that great genetic differentiation existed in this population of black wattle studied. This value is higher in comparison to other woody species; however it is similar to other acacia species. UPGMA cluster analysis using Nei's unbiased genetic distance, revealed four distinct clusters of groups corresponding to the distribution areas represented in this study. The Howick (group 400: unrelated) and Kumbula (group 85: unrelated) were more closely related to each other than to the other groups, since both these groups are from Natal. The Piet Retief groups (groups 47 and 50: half-sibs), branched-off together, indicating that they are distinct from the other groups. The pairwise analysis of identity showed that the relationship between the group from Howick (group 400: unrelated) and all the other groups from the other regions was the lowest, ranging from 64 % to 79 %. The relationship between all the groups beside the group from Howick (group 400: unrelated) was reasonably high, ranging from 78 % to 90 %. This distance displayed by group 400 (unrelated) from Howick in relation to the groups, is attributed to the fact that it is frost resistant and the other groups not. Genetic variation was also detected and partitioned, between and within groups, by Analysis of Molecular Variance (AMQVA). Majority of the variation existed within groups (82.65 %) but significant differentiation was recorded between groups (17.44 %). This high level of within group differentiation may be explained by many aspects, such as the species breeding system, genetic drift or genetic isolation of groups or populations. The application of RAPD fingerprinting in black wattle has provided a more in depth understanding of the genetic variation residing in the South African population. The results achieved implementing this technique has shown that significant genetic variation exists within the black wattle population in South Africa. The results obtained in this study are also important since it is contrary to the expectation that the black wattle population in South Africa has low genetic variation. This knowledge is of great value to genetically discriminate between individuals or groups, to improve the selection of superior genotypes and allowing improved quality control in breeding programmes and seed orchard management. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

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