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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.
1

Genomic instability in NSCLC detected by RAPD

Yeh, Yi-Jan 27 July 2001 (has links)
Abstract Lung cancer is one of the most common cancer death in Taiwan. The dead population of lung cancer are over five thousands per year. High mortality and bad prognosis displayed the severity of the lung cancer. RAPD (Random Amplified Polymorphic DNA), a simple technique for the detection of genomic instability, has been used in this research. We inquire into genetic variation in carcinogenesis, and find out genes association with NSCLC. Three or more than three DNA fragment patterns of normal and lung cancer samples exhibited by RAPD from the seven arbitrary were classified as genomic instability. Four out of seven arbitrary primers have been used for lung cancer RAPD analysis and three of them were newly designed in this investigation. Analysis of genomic instability with these seven random primers in twenty-seven NSCLC patients revealed that 81.48% of NSCLC exhibited genomic instability. The RAPD reproducibilities of primer 6 and primer 7 were the best among the seven primers used in this study. Therefore, the variable DNA fragments of primer 6 and primer 7 in RAPD analysis were subcloned and sequenced for the study of the possible mutated genes in NSCLC. Results showed that DNA gains or losses were found in chromosomes 2, 4, 6, 14 and 22. After bioinformatic searching and alignments with human Genebank, some oncogenes (such as RABL2B, c-fos, n-myc and mas1) and tumor suppressor gene (AR) were found located nearby the locus of these subclones. Genomic instability was investigated in relation with the clinical-pathological features such as age, stage, tumor size, metastasis, differential status, survival days and cancer types. Results, evaluated by the X2 test, were not significant except tumor stage.
2

Predikce odolnosti vůči fuzáriím DNA markery se zřetelem na kvalitu zrna ječmene

Hellebrandová, Lenka January 2006 (has links)
No description available.
3

Identificação da Variabilidade genética de Brachiaria ruziziensis por marcadores molecular / Genetic variability identification in Brachiaria ruziziensis by molecular marckers

Guaberto, Luciana Machado 27 November 2009 (has links)
Made available in DSpace on 2016-01-26T18:56:21Z (GMT). No. of bitstreams: 1 dissertacao.pdf: 398265 bytes, checksum: 21b224b71f75cac0dfab27ababfeb591 (MD5) Previous issue date: 2009-11-27 / Knowledge of the genetic variability of Brachiaria ruziziensis is required before you start a breeding program. This study investigated the genetic variability of 37 samples of Brachiaria ruziziensis, from the collection held by EMBRAPA Dairy Cattle by molecular markers and long primers. The DNA was extracted from leaves by CTAB method, we used 14 decamer primers and primers 9 long. The data were used for analysis of molecular variance (AMOVA) using the squared distances (Excoffier et al., 1992) using the program Arlequin (Excoffier et al., 2006). We found variation between species of 47.42% and 36.07% for RAPD primers and long, respectively and within the species observed variation of 52.58% and 63.93%. A dendrogram was constructed with the UPGMA clustering algorithm (Unweighted Pair-Group Method using an Arithmetic Average) using this analysis to the program NTSYS 2.0 (ROHLF 1998). Both markers were able to group the samples where genotypes 1 to 5 the most similar to each other. RAPD using primers short and long primers are effective to estimate the variability in Brachiaria ruziziensis. / O conhecimento da variabilidade genética de Brachiaria ruziziensis é necessário antes de iniciar-se um programa de melhoramento. Este trabalho objetivou estudar a variabilidade genética de 37 amostras de Brachiaria ruziziensis, provenientes de coleta realizada pela EMBRAPA Gado de leite por meio de marcadores moleculares RAPD e primers longos. O DNA das folhas foi extraído pelo método CTAB, utilizaram-se 14 primers decâmeros e 9 primers longos. Os dados foram utilizados para análise de variância molecular (AMOVA) utilizando-se as distâncias ao quadrado (EXCOFFIER et al., 1992) com auxílio do programa Arlequin (EXCOFFIER et al., 2006). Encontrou-se variação entre espécies de 47,42% e 36,07% para RAPD e primers longos, respectivamente e dentro da espécies observou-se variação de 52,58% e 63,93%. Foi construído um dendrograma com o algoritmo de agrupamento UPGMA (Unweighted Pair-Group Method Using an Arithmetic Average) utilizando-se para essa análise o programa NTSYS 2.0 (ROHLF, 1998).Ambos marcadores conseguiram agrupar os genótipos onde as amostras 1 a 5 foram as mais semelhantes entre si. RAPD utilizando-se primers curtos e primers longos são eficientes para estimar a variabilidade em Brachiaria ruziziensis.
4

Identificação da Variabilidade genética de Brachiaria ruziziensis por marcadores molecular / Genetic variability identification in Brachiaria ruziziensis by molecular marckers

Guaberto, Luciana Machado 27 November 2009 (has links)
Made available in DSpace on 2016-07-18T17:51:05Z (GMT). No. of bitstreams: 1 dissertacao.pdf: 398265 bytes, checksum: 21b224b71f75cac0dfab27ababfeb591 (MD5) Previous issue date: 2009-11-27 / Knowledge of the genetic variability of Brachiaria ruziziensis is required before you start a breeding program. This study investigated the genetic variability of 37 samples of Brachiaria ruziziensis, from the collection held by EMBRAPA Dairy Cattle by molecular markers and long primers. The DNA was extracted from leaves by CTAB method, we used 14 decamer primers and primers 9 long. The data were used for analysis of molecular variance (AMOVA) using the squared distances (Excoffier et al., 1992) using the program Arlequin (Excoffier et al., 2006). We found variation between species of 47.42% and 36.07% for RAPD primers and long, respectively and within the species observed variation of 52.58% and 63.93%. A dendrogram was constructed with the UPGMA clustering algorithm (Unweighted Pair-Group Method using an Arithmetic Average) using this analysis to the program NTSYS 2.0 (ROHLF 1998). Both markers were able to group the samples where genotypes 1 to 5 the most similar to each other. RAPD using primers short and long primers are effective to estimate the variability in Brachiaria ruziziensis. / O conhecimento da variabilidade genética de Brachiaria ruziziensis é necessário antes de iniciar-se um programa de melhoramento. Este trabalho objetivou estudar a variabilidade genética de 37 amostras de Brachiaria ruziziensis, provenientes de coleta realizada pela EMBRAPA Gado de leite por meio de marcadores moleculares RAPD e primers longos. O DNA das folhas foi extraído pelo método CTAB, utilizaram-se 14 primers decâmeros e 9 primers longos. Os dados foram utilizados para análise de variância molecular (AMOVA) utilizando-se as distâncias ao quadrado (EXCOFFIER et al., 1992) com auxílio do programa Arlequin (EXCOFFIER et al., 2006). Encontrou-se variação entre espécies de 47,42% e 36,07% para RAPD e primers longos, respectivamente e dentro da espécies observou-se variação de 52,58% e 63,93%. Foi construído um dendrograma com o algoritmo de agrupamento UPGMA (Unweighted Pair-Group Method Using an Arithmetic Average) utilizando-se para essa análise o programa NTSYS 2.0 (ROHLF, 1998).Ambos marcadores conseguiram agrupar os genótipos onde as amostras 1 a 5 foram as mais semelhantes entre si. RAPD utilizando-se primers curtos e primers longos são eficientes para estimar a variabilidade em Brachiaria ruziziensis.
5

Molecular methods for strain characterisation of Escherichia coli O157

Hopkins, Katie Louise January 2000 (has links)
No description available.
6

Caracterização molecular por AFLP (Amplified Fragment Length Polymorphism) de acessos de pinhão manso (Jatropha curcas L.) / Molecular Characterization by AFLP (Amplified Fragment Length Polymorphism) in accessions of physic nut (Jatropha curcas L.)

Redondo, Mariana Letícia Costa 09 June 2011 (has links)
O pinhão-manso (Jatropha curcas L.) é uma planta versátil e com diversos usos potenciais em especial para produção de biodiesel. O óleo obtido de suas sementes é seu produto mais rentável e atualmente desperta grande interesse econômico em diversos setores. A caracterização molecular e a avaliação do potencial reprodutivo dos acessos de pinhão-manso são aspectos ainda pouco abordados no Brasil, sendo necessária a caracterização de acessos brasileiros e suas potencialidades. Os objetivos do presente trabalho foram analisar a diversidade genética e a divergência genética em acessos comerciais de pinhão-manso, coletados no estado de São Paulo (Alvinlândia, Lins, Itatinga e Jales), Minas Gerais (Janaúba) e Mato Grosso do Sul (Dourados). Primeiramente, foram comparadas as técnicas de RAPD (Random Amplified Polymorphic DNA), RAPD-RFLP (Restrinction Fragment Length Polymorphism a partir do RAPD) e AFLP (Amplified Fragment Length Polymorphism), quanto à potencialidade de detectar polimorfismos dentro dos acessos e entre os acessos. Posteriormente, os acessos foram caracterizados através de AFLP. Além disso, este trabalho visou detectar se há diferença nas estruturas e no desenvolvimento floral e na taxa de viabilidade polínica dos acessos de São Paulo (Alvinlândia), Minas Gerais e Mato Grosso do Sul. Nessa parte do estudo, foram analisadas e identificadas as estruturas dos órgãos florais e do grão de pólen através das técnicas de microscopia de luz, eletrônica de varredura e transmissão. Na comparação entre as técnicas moleculares, apenas AFLP permitiu a detecção de polimorfismos, com base em um acesso escolhido para os testes (Alvinlândia, SP). As análises de todos acessos através de AFLP mostraram considerável polimorfismo, que foi refletido nas estimativas de diversidade genética de Nei e Índice de Shannon. Na análise de agrupamento, as amostras de cada acesso foram agrupadas coerentemente. Os acessos de Dourados e de Itatinga formaram um grupo separado, apresentando cerca de 76% de similaridade com o segundo grupo (Alvinlândia, Jales, Lins, Janaúba). Dentro deste último, os acessos de São Paulo ficaram agrupados (com cerca de 84% de similaridade), enquanto que Janaúba mostrou-se separado, com 82% de similaridade genética. Estes resultados indicam que os acessos de São Paulo provavelmente tenham origem a partir de Janaúba. No entanto, Itatinga provavelmente tenha origem a partir de Dourados. Quanto à morfologia floral, não foi observada nenhuma diferença a nível microscópico na formação e nas estruturas dos órgãos florais. Quando comparada a viabilidade polínica entre os dois acessos coletados em campo (Minas Gerais e Mato Grosso do Sul), notou-se que há diferença significativa na taxa de viabilidade, mesmo os valores sendo muito próximos (Mato Grosso do Sul - 81,91% e Minas Gerais - 77,20%), mostra que tanto os acessos de Minas Gerais como os de Mato Grosso do Sul podem ser utilizados como parentais masculinos em programas de melhoramento genético. A divergência genética moderada e a baixa variabilidade morfológica sugerem que coletas de materiais em poucos locais poderiam representar a diversidade genética da espécie. Estudos mais aprofundados, empregando técnicas como de microssatélites e mais acessos, são 11 necessários para o conhecimento da diversidade e estrutura genética do pinhão-manso no Brasil / Physic nut (Jatropha curcas L) is a very versatile plant with several potential uses especially for the production of biodiesel. The oil obtained from its seeds is the most profitable product of this specie and it is currently attracting great interest in various economic sectors. Molecular characterization and evaluation of reproductive potential of the accessions of pysic nut have still little attention in Brazil, it still need the characterization of Brazilian accessions and its potenciality. The ains of this study were: to analyze the genetic diversity and genetic divergence in commercial accessions of physic nut, from the States of São Paulo (Alvinlândia, Lins, Jales and Itatinga), Minas Gerais (Janaúba)and Mato Grosso do Sul (Dourados). Firstly we compared the RAPD (Random Amplified Polymorphic DNA) RAPD-RFLP (Fragment Length Polymorphism Restriction from RAPD) and AFLP (Amplified Fragment Length Polymprphism) regarding the potencial to detect polymorphism within the accessions and among accessions. Subsequently, the accessions were characterized by AFLP. Moreover this work aimed to detect whether there are differenced on flower structures and development and the rate of pollen viability on the accessions of São Paulo (Alvinlândia), Minas Gerias and Mato Grosso do Sul. On this part of the study were analysed and identified the structures of the floral organs and pollen grain through the techniques of, light microscopy, scanning electron and transmission microscopy. Comparing the molecular techniques, only AFLP allowed the detection of polymorphisms based on the accession chosen for testing (Alvinlândia, SP). Analyses of all accesses by AFLP showed considerable polymorphism, wich was reflected in estimates of genetic diversity index of Nei and Shannon. In cluster analysis, samples of each accessions were grouped consistently. The accessions of Dourados and Itatinga formed a separated group, with approximately 76% similarity with the second group (Alvinlândia, Jales, Lins, Janaúba). Within the last, accessions of São Paulo werte grouped (about 84% similarity), while Janaúba showed p separately, with 82% of genetic similarity. These results indicates that the accessions of São Paulo probably originates from Janaúba. However Itatinga probably originates from Dourados. As floral morphology, we observed no difference at microscope level on the formation and on the structures of floral organs. When compared the pollen grain viability between the two accessions collected in the field (Minas Gerais and Mato Grosso do Sul), it was noted that the viability rated were significantly different, even though the values being very close (Mato Grosso do Sul Minas Gerais 81,91% - 77,20%), shows that both the accessions of Minas Gerais as the Mato Grosso do Sul can be used as male parental in breeding programs. The moderate and low genetic divergence suggests that morphological variability collections of materials in a few locations could represent the genetis diversity of the species. Further studies employing techniques such as microsatellite and more accessions are required for an understanding of diversity and genetic structure of physic nut in Brazil
7

Phylogenie und Artidentifizierung bei Euplotes-Arten und ihren Endosymbionten /

Stremmel, Martin. January 1999 (has links) (PDF)
Universiẗat, Diss.--Kaiserslautern, 1999.
8

Caracterização molecular por AFLP (Amplified Fragment Length Polymorphism) de acessos de pinhão manso (Jatropha curcas L.) / Molecular Characterization by AFLP (Amplified Fragment Length Polymorphism) in accessions of physic nut (Jatropha curcas L.)

Mariana Letícia Costa Redondo 09 June 2011 (has links)
O pinhão-manso (Jatropha curcas L.) é uma planta versátil e com diversos usos potenciais em especial para produção de biodiesel. O óleo obtido de suas sementes é seu produto mais rentável e atualmente desperta grande interesse econômico em diversos setores. A caracterização molecular e a avaliação do potencial reprodutivo dos acessos de pinhão-manso são aspectos ainda pouco abordados no Brasil, sendo necessária a caracterização de acessos brasileiros e suas potencialidades. Os objetivos do presente trabalho foram analisar a diversidade genética e a divergência genética em acessos comerciais de pinhão-manso, coletados no estado de São Paulo (Alvinlândia, Lins, Itatinga e Jales), Minas Gerais (Janaúba) e Mato Grosso do Sul (Dourados). Primeiramente, foram comparadas as técnicas de RAPD (Random Amplified Polymorphic DNA), RAPD-RFLP (Restrinction Fragment Length Polymorphism a partir do RAPD) e AFLP (Amplified Fragment Length Polymorphism), quanto à potencialidade de detectar polimorfismos dentro dos acessos e entre os acessos. Posteriormente, os acessos foram caracterizados através de AFLP. Além disso, este trabalho visou detectar se há diferença nas estruturas e no desenvolvimento floral e na taxa de viabilidade polínica dos acessos de São Paulo (Alvinlândia), Minas Gerais e Mato Grosso do Sul. Nessa parte do estudo, foram analisadas e identificadas as estruturas dos órgãos florais e do grão de pólen através das técnicas de microscopia de luz, eletrônica de varredura e transmissão. Na comparação entre as técnicas moleculares, apenas AFLP permitiu a detecção de polimorfismos, com base em um acesso escolhido para os testes (Alvinlândia, SP). As análises de todos acessos através de AFLP mostraram considerável polimorfismo, que foi refletido nas estimativas de diversidade genética de Nei e Índice de Shannon. Na análise de agrupamento, as amostras de cada acesso foram agrupadas coerentemente. Os acessos de Dourados e de Itatinga formaram um grupo separado, apresentando cerca de 76% de similaridade com o segundo grupo (Alvinlândia, Jales, Lins, Janaúba). Dentro deste último, os acessos de São Paulo ficaram agrupados (com cerca de 84% de similaridade), enquanto que Janaúba mostrou-se separado, com 82% de similaridade genética. Estes resultados indicam que os acessos de São Paulo provavelmente tenham origem a partir de Janaúba. No entanto, Itatinga provavelmente tenha origem a partir de Dourados. Quanto à morfologia floral, não foi observada nenhuma diferença a nível microscópico na formação e nas estruturas dos órgãos florais. Quando comparada a viabilidade polínica entre os dois acessos coletados em campo (Minas Gerais e Mato Grosso do Sul), notou-se que há diferença significativa na taxa de viabilidade, mesmo os valores sendo muito próximos (Mato Grosso do Sul - 81,91% e Minas Gerais - 77,20%), mostra que tanto os acessos de Minas Gerais como os de Mato Grosso do Sul podem ser utilizados como parentais masculinos em programas de melhoramento genético. A divergência genética moderada e a baixa variabilidade morfológica sugerem que coletas de materiais em poucos locais poderiam representar a diversidade genética da espécie. Estudos mais aprofundados, empregando técnicas como de microssatélites e mais acessos, são 11 necessários para o conhecimento da diversidade e estrutura genética do pinhão-manso no Brasil / Physic nut (Jatropha curcas L) is a very versatile plant with several potential uses especially for the production of biodiesel. The oil obtained from its seeds is the most profitable product of this specie and it is currently attracting great interest in various economic sectors. Molecular characterization and evaluation of reproductive potential of the accessions of pysic nut have still little attention in Brazil, it still need the characterization of Brazilian accessions and its potenciality. The ains of this study were: to analyze the genetic diversity and genetic divergence in commercial accessions of physic nut, from the States of São Paulo (Alvinlândia, Lins, Jales and Itatinga), Minas Gerais (Janaúba)and Mato Grosso do Sul (Dourados). Firstly we compared the RAPD (Random Amplified Polymorphic DNA) RAPD-RFLP (Fragment Length Polymorphism Restriction from RAPD) and AFLP (Amplified Fragment Length Polymprphism) regarding the potencial to detect polymorphism within the accessions and among accessions. Subsequently, the accessions were characterized by AFLP. Moreover this work aimed to detect whether there are differenced on flower structures and development and the rate of pollen viability on the accessions of São Paulo (Alvinlândia), Minas Gerias and Mato Grosso do Sul. On this part of the study were analysed and identified the structures of the floral organs and pollen grain through the techniques of, light microscopy, scanning electron and transmission microscopy. Comparing the molecular techniques, only AFLP allowed the detection of polymorphisms based on the accession chosen for testing (Alvinlândia, SP). Analyses of all accesses by AFLP showed considerable polymorphism, wich was reflected in estimates of genetic diversity index of Nei and Shannon. In cluster analysis, samples of each accessions were grouped consistently. The accessions of Dourados and Itatinga formed a separated group, with approximately 76% similarity with the second group (Alvinlândia, Jales, Lins, Janaúba). Within the last, accessions of São Paulo werte grouped (about 84% similarity), while Janaúba showed p separately, with 82% of genetic similarity. These results indicates that the accessions of São Paulo probably originates from Janaúba. However Itatinga probably originates from Dourados. As floral morphology, we observed no difference at microscope level on the formation and on the structures of floral organs. When compared the pollen grain viability between the two accessions collected in the field (Minas Gerais and Mato Grosso do Sul), it was noted that the viability rated were significantly different, even though the values being very close (Mato Grosso do Sul Minas Gerais 81,91% - 77,20%), shows that both the accessions of Minas Gerais as the Mato Grosso do Sul can be used as male parental in breeding programs. The moderate and low genetic divergence suggests that morphological variability collections of materials in a few locations could represent the genetis diversity of the species. Further studies employing techniques such as microsatellite and more accessions are required for an understanding of diversity and genetic structure of physic nut in Brazil
9

Genome analysis of plant and insect pathogenic species of Verticillium using molecular DNA methodologies

Roberts, David Mark January 1999 (has links)
No description available.
10

Phylogenetic and antibiotic resistance variance amongst mastitis causing E. coli : the key to effective control / Daniël Johannes Goosen

Goosen, Daniël Johannes January 2012 (has links)
Environmental pathogens, such as Escherichia coli and Streptococcus uberis, are currently the major cause of mastitis within dairy herds. This leads to severe financial losses, lower production rates and deterioration of the general health of the herd. E. coli mastitis is becoming a major threat to high milk-producing dairy herds. This is because of its increasing resistance to antibiotics, rendering antibiotic treatment regimes against E. coli infections mostly ineffective. The aim of this study was to develop a method to select mastitis causing E. coli isolates for the formulation of effective herd specific vaccines. Two methods, namely a genotyping method (Random Amplification of Polymorphic DNA; RAPD) and an antibiogram based method, were used. A dairy farm milking approximately 1000 Holstein cows in the Darling area, Western Cape Province, was selected for this study. The study was conducted over a period of 48 months and mastitis samples were analysed for mastitis pathogens. Antibiogram testing (disk diffusion method) and an in-house developed RAPD analysis method were used to analyse the E. coli isolates. A total of 921 milk samples were analysed from which 181 E. coli isolates were recovered. The number of all other common mastitis pathogens combined was 99 isolates (Streptococcus uberis 18, Streptococcus dysgalactiae 46, Streptococcus agalactiae 1, Staphylococcus epidermidis 21, Arcanobacterium pyogenes 13). All E. coli isolates, except for one, were resistant to at least three antibiotics. Antibiotic variance profiles were also highly erratic. The RAPD analysis revealed high levels of polymorphisms and clear epidemiological trends were observed over time. No similarities in the variance profiles between the antibiotic variance data and phylogenetic data were observed. Formalin inactivated autogenous vaccines were produced containing E. coli isolated from the herd. The vaccines were formulated using the RAPD or antibiogram data of the E. coli isolates. A total of 5 vaccines were formulated using RAPD data (Rvaccines) and one vaccine was formulated using antibiotic variance data (A-vaccine). The RAPD formulated vaccines were more effective than the antibiotic variance formulated vaccine. After each R-vaccination, the number of E. coli mastitis cases declined within the herd. The A-vaccinations seemed to have had no effect, which lead to a rise in E. coli mastitis cases. RAPD analysis on new emerging isolates was able to detect genetic variation from vaccine strains, which in turn facilitated the formulation of new updated vaccines with higher effectiveness than the previous vaccine. Mastitis data prior to and after the vaccination period revealed significant higher incidences of mastitis in the herd than during the vaccination period. This study demonstrated that sufficient sampling practices coupled with a reliable genotyping method, resulted in the formulation of updatable vaccines which were highly effective in controlling E. coli mastitis within the herd. / Thesis (M Environmental Sciences)--North-West University, Potchefstroom Campus, 2012

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