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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.
201

Caracteriza??o morfoagron?mica e qu?mica de acessos de coqueiro-an?o e coqueiro-gigante

Sobral, Kamila Marcelino Brito 21 February 2017 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-12-18T21:43:02Z No. of bitstreams: 1 Tese_KamilaSobral.pdf: 1457947 bytes, checksum: 7c9ac5d23b1be9a47d34674e0490c6bf (MD5) / Made available in DSpace on 2017-12-18T21:43:02Z (GMT). No. of bitstreams: 1 Tese_KamilaSobral.pdf: 1457947 bytes, checksum: 7c9ac5d23b1be9a47d34674e0490c6bf (MD5) Previous issue date: 2017-02-21 / The genetic variability of the species Cocos nucifera L. that existing in Brazil is conserved in the International Coconut Germplasm Bank for Latin America and Caribe (ICG-LAC), which is located in the counties of Neopolis and Itaporanga d?Ajuda in the state of Sergipe, Brazil. Since from the establishment of the ICG-LAC some studies were carried out. However, this germplasm needs to be studied in depth comprising the morphoagronomical characterization, chemical and molecular evaluation in order to allow to estimate the genetic variability of the accessions. Thus, the aim of this work was to characterize morphologically coconut accessions (dwarfs and talls). The trials were carried out with eight tall coconut accessions in one cycle of production using 34 quantitative descriptors and with six dwarf coconut accessions in three cycles of production using 19 descriptors of fruits and 11 leave descriptors. The data obtained were subjected to univariate and multivariate analyses using the software GENES and Selegem. Among the accessions of tall coconuts the most dissimilar ones considering the morphoagronomical characters were Gigante-de-Rotuma and Gigante-do-Oeste Africano and they can be indicated as parents for coconut breeding programs. It was also found a great genetic variability among the coconut dwarf accessions of the ICG-LAC Bank, and this divergence was found to be consistent in the individual and joint analyses, including an analysis of maximum likelihood restricted (REML) taking into account a sample of morphological descriptors. The 14 coconut accessions (eight tall and six dwarfs) were used to perform a chemical evaluation of oil and their components in a cycle of crop production in two different field trials. It was found that some dwarf coconut accessions presented values of oil content similar to coconut tall accessions. Therefore, the best accessions can be exploited for coconut water as well as for production of oil and they can be selected as potential superior parents to be used in coconut breeding program. / A variabilidade gen?tica da esp?cie Cocos nucifera, L. existente no Brasil est? conservada no Banco Internacional de Germoplasma de Coco para Am?rica Latina e Caribe (ICG-LAC), localizado em Ne?polis e Itaporanga d?Ajuda em Sergipe, Brasil. Desde a implementa??o do ICG-LAC alguns estudos t?m sido realizados. No entanto, esse germoplasma precisa ser estudado em profundidade desde a caracteriza??o morfoagron?mica, qu?mica e molecular para se estimar a diversidade gen?tica dos acessos. Assim, o objetivo do trabalho foi caracterizar e avaliar morfoagronomicamente e quimicamente acessos de coqueiro-an?o e gigantes. Os experimentos foram conduzidos com oito acessos de coqueiros-gigantes em um ciclo de cultura e usando 34 descritores quantitativos e com seis acessos de coqueiros-an?es em tr?s ciclos da cultura utilizando-se 19 descritores de frutos e 11 descritores de folha. Os dados obtidos foram submetidos a an?lises univariadas e multivariadas usando o programa GENES e Selegem. Entre os acessos de coqueiros-gigantes avaliados os mais dissimilares pelas caracter?sticas agron?micas foram o Gigante-de-Rotuma e Gigante-do-Oeste-Africano, e estes podem ser indicados como genitores para programas de melhoramento. Foi encontrada tamb?m encontrada variabilidade gen?tica entre os acessos de coqueiro-an?o do banco ICG-LAC, diverg?ncia essa que se mostrou consistente nas an?lises individuais e conjuntas, incluindo uma an?lise de m?xima verossimilhan?a restrita (REML) usando uma amostra descritores morfol?gicos. Os 14 acessos de coqueiros (oito de gigantes e seis de an?es) foram analisados quanto ao teor de ?leo e seus componentes em um ciclo de cultura em dois experimentos separados. Constatou-se que alguns acessos de coqueiros-an?es apresentaram teor de ?leo pr?ximos dos valores obtidos pelos coqueiros-gigantes. Assim, os melhores acessos podem ser explorados tanto para ?gua de coco como para a produ??o de ?leo e s?o parentais potenciais para uso em programas de melhoramento do coqueiro.
202

Predi??o de par?metros gen?ticos e incremento da qualidade em frutos de prog?nies de aboboreira (Cucurbita moschata Duch.)

Faustino, Rita M?rcia Estigarribia Borges 17 March 2017 (has links)
Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-02-22T21:50:40Z No. of bitstreams: 1 PREDI??O DE PAR?METROS GEN?TICOS E INCREMENTO DA QUALIDADE DEFINITIVO.pdf: 1627949 bytes, checksum: 31c34b863f924737f87f81fa9f625403 (MD5) / Made available in DSpace on 2018-02-22T21:50:40Z (GMT). No. of bitstreams: 1 PREDI??O DE PAR?METROS GEN?TICOS E INCREMENTO DA QUALIDADE DEFINITIVO.pdf: 1627949 bytes, checksum: 31c34b863f924737f87f81fa9f625403 (MD5) Previous issue date: 2017-03-17 / The study aimed to estimate genetic parameters and genetic variability, as well as to determine the correlations among fruit variables associated with production and pulp quality attributes in pumpkin progenies. In 2013, the parameters and prediction of progeny gains allowed the ranking of the best individuals in 10 progenies from self pollination. In 2015 the divergence was determined, selecting genotypes for qualitative and quantitative characteristics, and studying the correlations among fruit variables associated with production and pulp quality attributes in 11 evaluated genotypes. In 2013, the REML/BLUP analysis allowed the ranking considering all variables evaluated indicating the individuals 10/1/1, 10/2/12 and 6/1/3 as more promising, being the first two of ?piriform? format, and the third of "moranga" format. In 2015, it was found great variability in the progenies evaluated and similarity among progenies C. moschata 1, C. moschata 3, C. moschata 4 and C. moschata 8. The promising progenies for fruit mass and ?-carotene were C. Moschata 4 and C. moschata 7 for advances aiming to increase of production and the nutritional characteristics of the fruit. Estimates of carotenoid contents generated by the Hue angle are only valid for contrasting genotypes due to the grouping of genotypes with carotenoid content four times higher than ?Jacarezinho? cultivar. The variables explained 98% of the variation in the basic variable in the path analysis and four variables can be used for direct selection aiming to increase of fruit mass. / O estudo objetivou obter estimativas de par?metros gen?ticos e de variabilidade gen?tica, bem como determinar as correla??es entre vari?veis do fruto associadas ? produ??o e atributos de qualidade da polpa em prog?nies de ab?bora. Em 2013, os par?metros e a predi??o de ganhos gen?ticos permitiram o ranqueamento dos melhores indiv?duos em 10 prog?nies provenientes de autofecunda??es. Em 2015 determinou-se a diverg?ncia, sendo feita a sele??o de gen?tipos para caracteres qualitativos e quantitativos, al?m de estudar as correla??es entre vari?veis do fruto associadas ? produ??o e atributos de qualidade da polpa em 11 gen?tipos avaliados. Em 2013, a an?lise via REML/BLUP possibilitou o ranqueamento considerando todas as vari?veis avaliadas indicando os indiv?duos 10/1/1, 10/2/12 e 6/1/3 como mais promissores, sendo os dois primeiros de formato ?piriforme? e o terceiro de formato ?moranga?. Em 2015, constatou-se grande variabilidade nas prog?nies avaliadas e similaridade entre as prog?nies C. moschata 1, C. moschata 3, C. moschata 4 e C. moschata 8. As prog?nies promissoras para massa do fruto e ?-caroteno foram C. moschata 4 e C. moschata 7 para avan?os visando aumento da produ??o e das caracter?sticas nutricionais do fruto. As estimativas dos teores de carotenoides geradas pelo ?ngulo Hue somente s?o v?lidas para gen?tipos contrastantes devido ao agrupamento de gen?tipos com teores de carotenoides quatro vezes maiores em rela??o a cultivar Jacarezinho. As vari?veis explicaram 98% da varia??o ocorrida na vari?vel b?sica na an?lise de trilha e quatro vari?veis podem ser utilizadas para a sele??o direta visando aumento da massa do fruto.
203

Variantes polim?rficas dos genes que codificam o CD14, TLR2, TLR4 e TNF-α envolvidos com o processo inflamat?rio em pacientes em condi??es cr?ticas de sa?de

Fallavena, Paulo Roberto Vargas 04 March 2011 (has links)
Made available in DSpace on 2015-04-14T14:51:09Z (GMT). No. of bitstreams: 1 431857.pdf: 2482469 bytes, checksum: b7a25df1538a26027ad365149defa70e (MD5) Previous issue date: 2011-03-04 / A condi??o cr?tica de sa?de ? causada pela intera??o de fatores gen?ticos e ambientais. Embora cada fator de risco em si j? esteja parcialmente sob controle gen?tico, estudos prop?em a exist?ncia de efeitos adicionais causados por genes de susceptibilidade; estes estudos iniciaram sugerindo variantes gen?ticas isoladas que poderiam aumentar o risco do paciente criticamente enfermo. Paralelamente, h? evid?ncias crescentes de que a inflama??o desempenha tamb?m um papel central nos pacientes com condi??es cr?ticas de sa?de. Durante a situa??o cr?tica, os fatores de risco cl?nicos e bioqu?micos convencionais s?o muito importantes, mas o estado inflamat?rio do paciente pode modular a gravidade do processo patol?gico. A inflama??o pode estar envolvida em todas as fases do desenvolvimento e das conseq??ncias da doen?a cr?tica, sendo o processo inflamat?rio um agente central da morbi-mortandade do paciente criticamente doente. Assim, controlando o estado inflamat?rio pode-se aumentar a chance do indiv?duo ter um melhor / pior desfecho. O CD14 (cluster of diferenciation 14) ? um receptor padr?o de reconhecimento de mol?culas envolvidas na resposta imune inata contra fatores ex?genos e end?genos de estresse. Os co-receptoes do CD14 mais importantes s?o TLR2, TLR4 (Toll-like Receptors), que s?o receptores transmembrana que mediam a resposta inflamat?ria por endotoxinas, e ativam a via do fator nuclear kappa B (NF-kappa B). O fator de necrose tumoral (TNF-α) ? outra citocina relevante no ?mbito do processo de inflama??o. Mas, al?m de seu papel protetor na imunidade inata, essas citocinas pr?-inflamat?rias podem exercer tamb?m efeitos patog?nicos. Em 2006, foi avaliada a influ?ncia do polimorfismo de nucleot?deo ?nico (SNP) -260C>T CD14 em uma amostra de 85 pacientes criticamente enfermos. Com uma distribui??o aleat?ria de gen?tipos para as caracter?sticas cl?nicas, como tempo de interna??o do paciente na Unidade de Terapia Intensiva (UTI), idade e tempo de perman?ncia hospitalar, foi observado que os pacientes -260TT CD14 apresentaram maiores ?ndices de sobreviv?ncia quando comparados com os portadores do alelo -260C CD14. Em 2009 foi testado uma amostra de 514 pacientes em estado cr?tico se o gen?tipo -260TT CD14 ocorreria mais frequentemente entre os sobreviventes do que entre os pacientes falecidos. Este estudo publicado mostrou que os resultados de 2006 se confirmaram com uma maior robustez. O SNP -260C>T CD14 foi um fator protetor para a sobreviv?ncia em pacientes gravemente doentes: houve uma frequ?ncia superior de sobreviventes homozigotos -260TT CD14. Estes resultados surgiram com a hip?tese de a maior frequ?ncia do gen?tipo -260TT CD14 em pacientes de UTI sobreviventes seria, possivelmente, explicada por um efeito de sinaliza??o na imunidade inata. Naquele momento (2009), a literatura atual estava sugerindo que a an?lise de uma s?rie de marcadores gen?ticos polim?rficos poderia ser mais informativa do que a an?lise de um ?nico polimorfismo. Ciente destas informa??es buscou-se a analisar SNPs em outros genes que codificam prote?nas com a??es sin?rgicas com o CD14 para verificar se eles tamb?m poderiam ser informativos no desfecho dos pacientes com condi??es cr?ticas de sa?de. Verificou-se a heran?a de variantes nos genes TLR2, TLR4, e TNF-α, os quais poderiam atuar em sinergia com o SNP -260C>T CD14 durante a condi??o cr?tica. Foram obtidos resultados que mostraram que SNPs 2029C>T e 2258G>A do TLR2, 896A>G e 1196C>T do TLR4 e o - 308G>A do TNF-α, isoladamente, n?o desempenham um papel significantemente not?vel no desfecho da doen?a cr?tica. No entanto, ao se realizar uma an?lise combinada com a heran?a do -260C>T CD14, foi detectado uma taxa de sobreviv?ncia significativamente maior no grupo de pacientes duplo homozigoto -260TT CD14/-308GG TNF-α. Na an?lise ajustada com o duplo gen?tipo as principais vari?veis cl?nicas preditoras de mortalidade, foram observadas que o duplo gen?tipo -260TT CD14/-308GG TNF-α foi um fator importante de prote??o para a sobreviv?ncia. Conectado ao efeito ben?fico do -260TT CD14, o gen?tipo -308GG TNF-α foi protetor contra a relatada superexpress?o de TNF-α causada por alelo -308A TNF-α. Em conclus?o, os resultados ap?iam a hip?tese de que a intera??o entre os SNPs funcionais - 260TT CD14 e -308GG TNF-α pode estar influenciando o desfecho de pacientes criticamente enfermos
204

A influ?ncia do polimorfismo do super?xido dismutase dependente de mangan?s 2 na morbi-mortalidade p?s-operat?ria de pacientes submetidos a cirurgias oncol?gicas

Piant?, Christina Duarte 19 December 2005 (has links)
Made available in DSpace on 2015-04-14T13:35:37Z (GMT). No. of bitstreams: 1 444737.pdf: 628352 bytes, checksum: c24f3ccf9b1b08feecb9e9c2a2e72134 (MD5) Previous issue date: 2005-12-19 / Cancer is one of the leading causes of morbidity and mortality in Brazil and worldwide, and surgery is very often its primary treatment. Manganese-dependent superoxide dismutase (SOD 2) is one of the main intracellular antioxidant enzymes, participating directly in the protection of the cell against oxidative reactions, which are thought to be pivotal in carcinogenesis. Diminished expression of SOD 2 is found in a number of different neoplasms, and in some of them is correlated to an adverse prognosis. The present study was designed to correlate SOD 2 genetic polymorphism with postoperative morbidity and mortality in patients submitted to oncologic surgery at a university hospital, and to characterize the postoperative complications observed. We performed a prospective, observational study of 88 adult patients submitted to oncologic surgeries. Mean + SD age was 61 + 7.4 years; 59% of patients were male. Some co-morbidity was present in 76% of patients in the preoperative evaluation, of which the most common was arterial hypertension (47.7%). Most surgeries were performed in the gastrointestinal tract (85.2%), in most cases approaching the stomach or colon. Adenocarcinoma of the gastrointestinal tract was the most commonly found histological tumor type (80.7%). In 30.7 of patients, there was lymph node involvement. Postoperative complications occurred in 57% of patients, with sepsis (27.3%) and bronchopneumonia (11.4%) being the most frequent. Operative mortality (up to 30 postoperative days) was of 21.6%; the main cause of death was sepsis (63.2%). Allelic frequencies of SOD 2 genetic polymorphisms were: allele A 54% and allele B 45%. Genotypic frequencies observed were: genotype AA 34.1%, genotype BB 25%, and genotype AB 40.9%. There was no statistically significant association between preoperative variables and SOD 2 genetic polymorphism. The only postoperative variable associated to SOD 2 genetic polymorphism was urinary tract infection, which occurred exclusively in AA genotype patients (P = 0.002). When we evaluated the association between the presence of the A allele (genotypes AA and AB) of SOD 2 and preoperative variables, there was a positive correlation with diabetes mellitus (P = 0.04). There was no association between the presence of the A allele (genotypes AA and AB) and postoperative variables. When we evaluated the association of the presence of the B allele (genotypes AB and BB) of SOD 2 and preoperative variables, there was a positive correlation with cardiovascular disease (P = 0.01). When we evaluated the association of the presence of the B allele (genotypes AB and BB) of SOD 2 and postoperative variables, there was a positive correlation with urinary tract infections (P = 0.001) and stroke (P = 0.04). There was a borderline association between the presence of the B allele (genotypes AB and BB) of SOD 2 enterocutaneous fistula (P = 0.1). The present study implies that SOD 2 gene polymorphism does not seem to significantly influence postoperative morbidity and mortality in patients submitted to oncologic surgery. / O c?ncer ? uma das principais causas de morbi-mortalidade nos dias de hoje no Brasil e no mundo, e seu tratamento inicial ? cir?rgico em grande parte das situa??es. A super?xido dismutase dependente de mangan?s (SOD 2) ? a principal enzima antioxidante intracelular, participando ativamente na defesa da c?lula contra rea??es oxidativas, potenciais causadoras do processo de carcinog?nese. A express?o reduzida da SOD 2 ? verificada em diversas neoplasias, sendo correlacionada com progn?stico adverso em alguns tumores. O presente estudo objetivou correlacionar o polimorfismo do gene da SOD 2 e a morbi-mortalidade p?soperat?ria nos pacientes submetidos a cirurgias oncol?gicas em um hospital universit?rio, bem como caracterizar as frequ?ncias das complica??es p?soperat?rias destes pacientes. Foi realizado um estudo prospectivo, observacional, com 88 pacientes adultos submetidos a cirurgias oncol?gicas. A m?dia das idades dos pacientes foi de 61 + 7,4 anos; 59% dos pacientes eram do g?nero masculino. Dos operados, 76% apresentavam alguma co-morbidade no pr?-operat?rio, dentre as quais a hipertens?o arterial sist?mica foi a mais comum (47,7%). A maioria das cirurgias foi realizada no trato gastrintestinal (85,2%), na maior parte dos casos abordando est?mago e c?lon. O adenocarcinoma do trato gastrintestinal foi o tipo histol?gico mais frequentemente encontrado (80,7%). Comprometimento linfonodal pela neoplasia foi verificado em 30,7% dos pacientes. Complica??es p?s-operat?rias ocorreram em 57% dos pacientes, sendo que as mais frequentes foram s?psis (27,3%) e broncopneumonia (11,4%). A mortalidade operat?ria (at? 30 dias) foi de 21,6%; a principal causa de ?bito foi s?psis (63,2%). As frequ?ncias al?licas dos polimorfismos da SOD 2 foram: 54% para o alelo A e 45% para o alelo B. As frequ?ncias genot?picas observadas foram: 34,1% com gen?tipo AA, 25% com gen?tipo BB, e 40,9% com gen?tipo AB. N?o foi observada correla??o estat?stica entre vari?veis pr?-operat?rias e o polimorfismo do gene da SOD 2. Apenas uma das vari?veis p?s-operat?rias avaliadas (infec??o do trato urin?rio, a qual ocorreu somente entre os pacientes com gen?tipo AA) demonstrou associa??o com o polimorfismo do gene da SOD 2 (P = 0,002). Ao analisarmos a associa??o entre a presen?a do alelo A (gen?tipos AA e AB) da SOD 2 e os aspectos pr?-operat?rios observamos uma associa??o entre a mesma e a presen?a de diabete m?lito (P = 0,04). N?o houve associa??o entre a presen?a do alelo A (gen?tipos AA e AB) e vari?veis p?s-operat?rias. Ao avaliarmos a associa??o entre a presen?a do alelo B (gen?tipos AB e BB) da SOD 2 e vari?veis pr?-operat?rias, observamos uma correla??o positiva entre a mesma e doen?as cardiovasculares (P = 0,01). Ao avaliarmos a associa??o entre a presen?a do alelo B (gen?tipos AB e BB) da SOD 2 e vari?veis p?s-operat?rias, verificamos a associa??o entre a mesma e a ocorr?ncia de infec??o do trato urin?rio (P = 0,001) e acidente vascular cerebral (P = 0,04). Apresentou signific?ncia lim?trofe a associa??o entre a presen?a do alelo B (gen?tipos AB e BB) da SOD 2 e a ocorr?ncia de f?stula ?ntero-cut?nea (P = 0,1). O presente estudo permite concluir que o polimorfismo do gene da SOD 2 n?o parece influenciar de maneira significativa a ocorr?ncia de morbi-mortalidade p?soperat?ria em pacientes submetidos a cirurgias oncol?gicas.
205

Identifica????o de genes envolvidos na degrada????o de xilana por meio de abordagens gen??mica e metagen??mica

Schroeder, Lu??s Felipe 30 September 2014 (has links)
Submitted by Kelson Anthony de Menezes (kelson@ucb.br) on 2016-12-19T18:17:11Z No. of bitstreams: 1 LuisFelipeSchroederDissertacao2014.pdf: 2932891 bytes, checksum: 9867ac60d140318b946ef45528984bca (MD5) / Made available in DSpace on 2016-12-19T18:17:11Z (GMT). No. of bitstreams: 1 LuisFelipeSchroederDissertacao2014.pdf: 2932891 bytes, checksum: 9867ac60d140318b946ef45528984bca (MD5) Previous issue date: 2014-09-30 / There are different process being developed for cellulosic ethanol production, with possible different pretreatments with varying temperatures and pH, in addition to several biomasses can be used as the source of fermentable sugars. Among the important enzymes for deconstruction of plant biomass, stand out xylanases. These enzymes are responsible for deconstruction of the hemicellulose present in the structure of the plant cell walls. There are several ways to accomplish the identification of these enzymes: purification from an isolated microorganism is one. In this study, genomic and metagenomic approaches were used to carry out the prospection of the genes responsible for coding these enzymes. Clones from two libraries were used for detection and evaluation of activity on solid medium, supplemented with xylan and acid pretreated sugarcane bagasse. Nineteen clones of a goat rumen metagenomic library and five clones from an AB60 bacterium genomic library, with 15,000 clones constructed in this study, were selected initially. Fourteen clones from the metagenomic library were completely sequenced and their ORFs were analyzed. Four clones from the genomic library were partially sequenced and one clone had its sequence completely determined and 104 ORFs were obtained for all clones completely or partially sequenced ORFs were analyzed. Eleven ORFs showed some similarity to genes of importance for the degradation of complex polysaccharides. Among the most important ORFs and most likely to be related to the detected activity, are genes coding for ??-glucosidase, ??-xylosidase and ??-glucuronidase. Furthermore, also other ORFs with lower probability of relation with the activity or necessity to full sequencing of the clones for a few more conclusive analysis were identified. About 40% of the ORFs present in the rumen clones and 37.8% of the ORFs present in Acidobacteria clones showed similarity with hypothetical or uncharacterized proteins, which could be important in the activity detected. A ??-glucuronidase gene detected in a clone from the goat rumen metagenomic library was synthesized, its sequence was optimized for expression in Escherichia coli. However, in the present work, it was not possible to sub-cloning, made expression and purification of this enzyme. Some ORFs detected can be used for future studies of expression and characterization in order to improve knowledge about biotechnological potential present in the rumen and acidobacteria AB60, besides the ecological role of these microorganisms in their environment. / Existem diversos processos em desenvolvimento para a produ????o de etanol celul??sico, havendo diferentes poss??veis pr??-tratamentos, com temperaturas e pH variados, al??m das diversas biomassas que podem ser utilizadas como fonte de a????cares ferment??veis. Dentre as enzimas importantes para a desconstru????o de biomassa vegetal, destacam-se as xilanases. Estas enzimas s??o respons??veis pela desconstru????o da estrutura hemicelul??sica presente na parede celular das plantas. H?? diversas maneiras para alcan??ar a identifica????o destas enzimas: purifica????o a partir de micro-organismo isolado sendo uma delas. No presente trabalho, foram utilizadas abordagens gen??mica e metagen??mica a fim de realizar a prospec????o dos genes respons??veis pela codifica????o para estas enzimas. Foram utilizados clones oriundos de duas bibliotecas para a detec????o e avalia????o da atividade em meio s??lido suplementado com xilana e baga??o de cana-de-a????car pr??-tratado com ??cido. Dezenove clones de uma biblioteca metagen??mica de r??men de caprinos e cinco clones de uma biblioteca gen??mica da bact??ria AB60, com 15.000 clones constru??da no presente trabalho, foram selecionados inicialmente. Quatorze clones da biblioteca metagen??mica foram sequenciados completamente e tiveram as suas ORFs analisadas. Quatro clones da biblioteca gen??mica foram parcialmente sequenciados e um clone teve a sua sequ??ncia completa determinada e as ORFs analisadas. Das 104 ORFs obtidas de todos os clones completamente ou parcialmente sequenciados, onze ORFs apresentaram alguma similaridade com genes de import??ncia para a degrada????o de polissacar??deos complexos. Dentre as ORFs de maior import??ncia e com maior probabilidade de estarem relacionadas com a atividade detectada, est??o genes codificantes para ??-glicosidase, ??-xilosidase e ??-glicuronidase. Al??m disso, tamb??m foram identificadas outras ORFs com menor probabilidade de rela????o com a atividade ou necessidade de sequenciamento completo de alguns dos clones para uma an??lise mais conclusiva. Cerca de 40% das ORFs presentes nos clones selecionados de r??men e 37,8% das ORFs presentes nos clones selecionados de Acidobacteria apresentaram similaridade com prote??nas hipot??ticas ou prote??nas n??o caracterizadas que podem ter import??ncia na atividade detectada. Um gene de ??-glicuronidase detectado em um clone da biblioteca metagen??mica de r??men de caprino foi sintetizado, otimizando-se sua sequ??ncia para express??o em Escherichia coli . Entretanto, n??o foi poss??vel a sub-clonagem, express??o e purifica????o desta enzima no presente trabalho. Algumas ORFs detectadas podem ser utilizadas para estudos futuros de express??o e caracteriza????o a fim de aprimorar o conhecimento a respeito do potencial biotecnol??gico presente no r??men e na Acidobact??ria AB60, al??m do papel ecol??gico destes micro-organismos em seu ambiente.
206

PATHOGENITÄTSVERGLEICH VON SALMONELLA TYPHIMURIUM DT104 - WILDTYP UND SALMONELLA TYPHIMURIUM - DELETIONSMUTANTEN (sseD::aphT & invC::aphT) IN PERSISTENT INFIZIERTEN SCHWEINEN / COMPARISON OF THE PATHOGENICITY OF SALMONELLA TYPHIMURIUM DT104 WILD TYPE AND SALMONELLA TYPHIMURIUM DELETIONSMUTANTS (sseD::aphT & invC::aphT) IN PERSISTENT INFECTED PIGS

Sigmarsson, Haukur Lindberg 12 November 2012 (has links) (PDF)
ZUSAMMENFASSUNG Haukur Lindberg Sigmarsson PATHOGENITÄTSVERGLEICH VON SALMONELLA TYPHIMURIUM DT104 - WILDTYP UND SALMONELLA TYPHIMURIUM - DELETIONSMUTANTEN (sseD::aphT & invC::aphT) IN PERSISTENT INFIZIERTEN SCHWEINEN Salmonella (S.) Typhimurium DT104 ist ein gram-negatives Bakterium. Es weist keine Wirtsspezifität auf und gilt als Zoonoseerreger. Jährlich erkranken daran allein in Deutschland mehrere Tausend Menschen unter dem Bild einer schwerwiegenden Diarrhö mit zum Teil tödlichem Ausgang. Das Schwein gilt als eines der Reservoire für S. Typhimurium DT104 des Menschen. S. Typhimurium DT104 gelangt über vom Schwein stammende Produkte in den menschlichen Verzehr. Die Kontrolle von S. Typhimurium DT104 einschließlich effektiver Eradikationsmassnahmen in unseren Schweinebeständen ist deshalb von entscheidender Bedeutung, um den Eintrag dieses Bakteriums in die menschliche Nahrungskette wenn möglich zu eliminieren. Dafür ist das Verständnis über S. Typhimurium DT104 einschließlich der Kenntnis seine Pathogenitätseigenschaften notwendig. Ziel dieser Arbeit waren Untersuchungen zur Pathogenität von S. Typhimurium DT104. Dabei wurden der Wildstamm mit zwei seiner Deletionsmutanten (sseD::aphT und invC::aphT) verglichen. Die Untersuchungen erfolgten im Infektionsversuch an insgesamt 25 sechs Wochen alten männlichen Schweinen, die in einem vollklimatisierten Versuchsstall gehalten wurden. Den Tieren wurde im Anschluss an eine einwöchige Akklimatisierungsphase eines der nachfolgenden Stämme von S. Typhimurium DT104 oral in einer Konzentration von 1 x 1011 KBE verabreicht: Wildtyp (n = 8 Schweine), Deletionsmutante seeD::aphT (n = 8) und Deletionsmutante invC::aphT (n = 9). Bei den Mutanten handelt es sich um Varianten von S. Typhimurium DT104, die an den entsprechenden Abschnitten des Bakteriumgenoms (d.h. sseD-Gen bzw. invC-Gen) deletiert wurden. SseD regelt die Überlebensfähigkeit von S. Typhimurium in Makrophagen, invC dessen Invasionsvermögen. Im Mäusemodel war die Pathogenität beider Mutanten deutlich vermindert. Nach der Infektion schloss sich ein 20 tägiger Beobachtungszeitraum an, während dessen nachfolgend genannte Parameter erfasst bzw. Proben genommen wurden: klinische Symptome (Allgemeinbefinden, Erbrechen, Durchfall, Futteraufnahme, Atmung, Temperatur); Blutentnahme für Erstellung des weißen Blutbildes; Kotentnahme zum Nachweis der Ausscheidung von S. Typhimurium. Einen Tag nach Ende der Beobachtung wurden die Tiere getötet und Proben von insgesamt 15 Organen (unter anderem Tonsille; Colon und Caecum sowie dazugehörige Lymphknoten; Leber; Milz; Muskulatur) genommen. Kot sowie Gewebeproben wurden kulturell und wenn positiv auch mittels PCR untersucht. Alle mit dem Wildtyp infizierten Schweine wurden mehr oder weniger stark krank. Häufig zeigten erkrankte Schweine zeitgleich mehrere Krankheitssymptome (z. B. Erbrechen und Durchfall). Die Erkrankung hielt über mehrere Tage an. Im Vergleich dazu waren die Krankheitssymptome der Tiere, die mit Mutanten infiziert wurden, mild. Nur wenige Tiere erkrankten und dann auch nur kurzzeitig. Gewöhnlich war nur einer der erfassten Parameter verändert. Typische Veränderungen im weißen Blutbild waren nur bei Wildtyp-infizierten Tieren zu beobachten, während Tiere beider Mutanten kaum auf die Infektion reagierten. Alle 25 infizierten Tiere schieden S. Typhimurium mit dem Kot während der ersten Woche post inocculationem aus. Danach wurden in allen drei Gruppen etwa gleichviel intermittierende Ausscheider beobachtet. Zwischen 65 und 67 % der Gewebeproben der mit dem Wildtyp und mit der sseD::aphT-Mutante infizierten Tiere waren sowohl in der Kultur als auch mittels PCR S. Typhimurium positiv, während dieser Anteil nach Infektion mit invC::aphT nur 49 % betrug. Alle Tiere waren in Mandibularlymphknoten und im Colon positiv, während S. Typhimurium nur selten in Muskulatur und Leber nachzuweisen war. Die Ergebnisse dieser Arbeit bestätigen, dass Infektionen mit dem Wildtyp von S. Typhimurium zu einer schweren Erkrankung führen können. Gleichzeitig konnte gezeigt werden, dass beide in dieser Arbeit verwendeten Mutanten weniger krankmachend sind. Es muss davon ausgegangen werden, dass die Deletionen in den sseD bzw. invC-Bereichen tatsächlich zu Veränderungen bestimmter Eigenschaften geführt haben, die Teil der Pathogenitätsmechanismen für das Schwein sind. Im Unterschied zur Maus war sseD beim Schwein allerdings invasiv. Es kann vermutet werden, dass die durch sseD kodierten Pathogenitätseigenschaften von S. Typhimurium bei der Maus anders als beim Schwein wirken und somit unterschiedliche Bedeutung haben. Da die invC::aphT-Mutante jedoch und wie erwartet wesentlich schwächer als Wildtyp und sseD::aphT invadierte ist davon auszugehen, dass die Deletion im invC Bereich das Invasionsvermögen der Mutante beim Schwein ähnlich wie bei der Maus verringerte.
207

Eine Analyse ausgewählter genomischer Varianten im FIGF- und ACE2-Gen und deren Bedeutung in der molekularen Pathogenese intrakranieller Aneurysmen

Leonhardt, Mareike 26 January 2010 (has links) (PDF)
In der vorliegenden Arbeit untersuchten wir an einer europäischen Population ausgewählte Polymorphismen zweier Gene auf eine Assoziation zu IA. Beide Gene FIGF und ACE2 sind lokalisiert auf Chromosom Xp22 und stellen damit positionelle Kandidatengene dar, aber auch funktionell sind sie von Interesse, da sie v.a. in Prozesse des Gefäßwachstums (FIGF) und der Blutdruckregulierung (ACE2) involviert sind; Vorgänge also, die möglicherweise in die pathophysiologische Erklärung der IA Entstehung mit hineinspielen. In keinem der insgesamt neun analysierten Polymorphismen konnten wir jedoch eine signifikante Assoziation zu IA finden. Auch eine Analyse möglicher intra- und intergenetischer Haplotypen aller untersuchten Varianten erbrachte kein signifikantes Ergebnis.
208

Molecular Characterization of the Male Germ Cell Expressed Genes Hook1 and TSEP22 / Molekular Charakterisierung der Hook1 und TSEP22 Gene, die in Männlicher Kernzellen exprimiert sind -

Mendoza-Lujambio, Irene 30 October 2001 (has links)
No description available.
209

Nachweis von Salmonella und Yersinia enterocolitica im persistent infizierten Schwein

Arnold, Thorsten 28 November 2004 (has links) (PDF)
Die Infektion mit Salmonella und Yersinia (Y.) enterocolitica über Produkte tierischen Ursprungs stellt nach wie vor ein ungelöstes Problem des gesundheitlichen Verbraucherschutzes dar. Will man diese Zoonoseerreger aus der Lebensmittelkette fernhalten, sind moderne und gut validierte Nachweissysteme erforderlich. Eine Infektion von Schweinen erfolgt überwiegend im Mastbetrieb mit Infektionsdosen, die nur zu einer milden klinischen Symptomatik führen. In den meisten Fällen überstehen die Tiere die Infektion mit Salmonella und Y. enterocolitica und werden zu klinisch inapparenten Keimträgern. Solche Schweine stellen ein Reservoir für die Infektion anderer Tiere und für den Eintrag in die Lebensmittelkette dar. Im Rahmen dieser Arbeit wurden zwei PCR-Methoden zum spezifischen Nachweis von Salmonella und Y. enterocolitica im Schlachtschwein entwickelt und anhand von Probenmaterial aus eigens dafür durchgeführten Infektionsversuchen mit S. Typhimuirum und Y. enterocolitica evaluiert. Beide Methoden mussten sich am diagnostischen Goldstandard für den jeweiligen Erreger messen lassen. Für Salmonella Typhimurium wurde die ISO-Norm 6579 und für Y. enterocolitica die ISO-Norm 10273 zum kulturellen Nachweis ausgewählt. Es konnte eine neue PCR-Methodik zum Salmonella-Nachweis in 14 verschiedenen Gewebeproben etabliert werden, die im Vergleich zum kulturellen Nachweis nach ISO 6579 eine Sensitivität von 100 % und eine Spezifität von 96 % aufweist und die Zeitspanne bis zum spezifischen Nachweis des Erregers um mindestens 24 Stunden reduziert. Die Untersuchungen erfolgten anhand von 420 Gewebeproben aus persistent infizierten Schweinen aus Infektionsversuchen mit S. Typhimurium DT104. Dieses neu entwickelte und validierte PCR-Verfahren wurde mit einem bereits etablierten PCR-Nachweissystem nach RAHN et al. (1992) - wie in der DIN 10135 angegeben - verglichen. Beide PCR-Methoden basieren auf dem invA-Virulenzgen von S. Typhimurium. Im Infektionsversuch konnten zwei Gewebeproben (Caecum und Lnn. Ileocolici) bestimmt werden, durch deren Kombination man mit beiden Nachweismethoden 96 % (23 von 24 Tieren) aller im Versuch infizierten Schweine als Salmonella positiv identifizieren konnte. Erstmals gelang in dieser Arbeit der Nachweis des yopT-Gens bei plasmidtragenden Y. pseudotuberculosis-Stämmen sowie die Bestimmung der Sequenz (European Bioinformatics Institute, Accession-Number: AJ304833). Das yopT-Gen kodiert für ein 35,5 kDa großes Effektor-Protein, das einen zytotoxischen Effekt auf HELA-Zellen und Makrophagen besitzt. Durch den Nachweis des yopT-Gens bei Y. pseudotuberculosis-Stämmen war es erstmals möglich, eine für Y. enterocolitica spezifische, auf dem yopT-Gen des Virulenzplasmids basierende PCR-Methode zu etablieren, die auch die Diskriminierung von Y. pseudotuberculosis-Isolaten gestattet. In einem weiteren Infektionsversuch konnte gezeigt werden, dass es die auf dem yopT-Gen von Y. enterocolitica basierende PCR-Methode erlaubt, Carrier-Tiere mit hoher Sensitivität (100 %) und Spezifität (87 %) innerhalb von 56 Stunden in lymphatischen Geweben zu identifizieren. Besonders geeignet für den Nachweis mit der ISO 10273 und dem neu etablierten yopT PCR-Verfahren waren das Ileum und die Lnn. ileocolici. In dieser Arbeit ist der Versuch gelungen, die Diagnostik für zwei der drei wichtigsten beim Schwein vorkommenden humanen Enteritiserreger zu standardisieren, indem Kombinationen aus Gewebeproben bestimmt wurden, die sowohl für den Nachweis mit der jeweiligen Goldstandard-Methode als auch mit den schnelleren und sensitiveren PCR-Methoden geeignet sind. Die Ergebnisse dieser Arbeit tragen zu einer deutlichen Verbesserung der Diagnostik von Salmonella und Y. enterocolitica beim Schlachtschwein bei. Es bleibt zu hoffen, dass somit der Eintrag dieser Zoonoseerreger in die Lebensmittelkette reduziert und der Verbraucherschutz auf diesem Gebiet beträchtlich verbessert werden kann. / The infection with Salmonella and Yersinia (Y.) enterocolitica through foodstuff from slaughter pigs is one of the major problems of hygienic consumer protection. To avoid the contamination of products from pig industry modern and well validated bacteriological identification systems are necessary. An infection predominantly occurs in the fattening pens, showing mild clinical symtoms only. The majority of infected pigs overcome the infection with Salmonella and Y. enterocolitica and become clinically inapparent carrier pigs. Those pigs are a reservoir for the contamination of other animals and pork products. In the context of this work two PCR-assays for the specific detection of Salmonella and Y. enterocolitica have been developed and validated on the basis of tissue samples from experimentally infected pigs. Both methods have been compared with the classical bacterial culture. Two international standards were used for bacterial detection: ISO 6579 for S. Typhimurium and ISO 10273 for pathogenic Y. enterocolitica. It was possible to establish a new PCR-assay for the specific detection of Salmonella in 14 different tissues of experimentally infected pigs. In comparison to the standard ISO 6579 a sensitivity of 100 % and a specificity of 96 % were calculated for the PCR-assay. The investigations were carried out with 420 tissue samples of persistently infected pigs that have been experimentally infected with S. Typhimurium. By using the PCR-method for the detection of Salmonella in positive tissue samples, the detection-time could be reduced around 24 hours. The new PCR-assay developed and validated in this work, was compared with the PCR-method described in DIN 10135, which is based on the studies of RAHN et al. (1992). Both methods were based on the invA-virulence gene of S. Typhimurium. A combination of samples from ileocolic lymph node and caecum was particularly suitable for the detection of 96 % of the experimentally infected pigs (23 off 24 animals) with the PCR-assay and the culture method. In this study, the yopT-gene was proved for the first time to be present in plasmid bearing Y. pseudotuberculosis-Isolates, and the nucleotid sequence was determined (European Bioinformatics Institute, Accession-Number: AJ304833). YopT encodes a 35.5 kDa effector protein (YopT), which induces a cytotoxic effect in HeLa cells and macrophages. This finding was used to develop a specific PCR-assay for the detection of pathogenic Y. enterocolicica strains and the discrimination from pathogenic Y. pseudotuberculosis strains. Embedded in an experimental Y. enterocolitica-infection-model in swine, it was shown that the yopT PCR-assay is suitable for the detection of pathogenic Y. enterocolitica in lymphatic tissue of persistently infected pigs. The yopT PCR-method shows a sensitivity of 100 % and a specificity of 87 % in lymphatic tissue. By the use of the PCR-assay, the detection of Y. enterocolitica was possible within 56 hours. A combination of specimens from the ileum and ileocolic lymph nodes was most suitable for the detection of pathogenic Y. enterocolitica in slaughter pigs with the ISO-Standard 10273 and the yopT PCR. This investigation succeeded in standardizing the identification of two of the three most important zoonotic agents for human enteric disease. The standardization was achived by the use of a combination of samples suitable for the identification with both, the “Goldstandard” and the specific and rapid PCR-method. The results of this work offer a better identification of Salmonella and Y. enterocolitica in slaughter pigs in the future. Based on these facts it is possible to avoid contamination of food products from slaughter pigs and to improve the hygienic consumer protection considerably.
210

Uso sustent?vel da Copernicia prunifera (Miller) H. E Moore no semi?rido potiguar: valoriza??o de saberes e conserva??o dos recursos gen?ticos

Sousa, Rodrigo Ferreira de 28 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:17:53Z (GMT). No. of bitstreams: 1 RodrigoFS_DISSERT.pdf: 1032742 bytes, checksum: 297b239b5ca1673f55e18c42d7327117 (MD5) Previous issue date: 2014-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Copernicia prunifera (Arecaceae), popularmente conhecida como carna?ba, ? nativa da regi?o nordeste do Brasil, com ocorr?ncia ao longo das margens de rios e ?reas alagadi?as. Por ser vers?til em rela??o ?s formas de usos, essa palmeira ficou conhecida como ?rvore da vida , sendo o p? cer?fero o principal produto extra?do da C. prunifera. Este estudo teve como objetivos investigar aspectos etnoecol?gicos e etnobot?nicos da C. prunifera em uma comunidade extrativista, selecionar primers ISSR (Inter Simple Sequence Repeat) para estudos de gen?tica de popula??es, e estudar a diversidade e a estrutura gen?tica de uma popula??o natural no Estado do Rio Grande do Norte, Brasil. Foram entrevistados 11 moradores considerados informantes-chaves na regi?o de Ipangua?u/RN, onde 73% dos informantes relataram a ocorr?ncia de um morfotipo diferente de carna?ba, conhecida como carna?ba branca . Dos entrevistados, 82% afirmaram que a esp?cie possui dispers?o realizada por morcegos. Na etnobot?nica, o p? cer?fero foi citado por todos como o produto mais importante extra?do da C. prunifera e a folha a parte mais usada (45%), seguida dos frutos (29%), caule e raiz (ambas com 13%). Na sele??o de primers ISSR, dos 17 que foram testados, 12 amplificaram o DNA e, destes, sete foram selecionados para caracterizar a estrutura gen?tica de 37 indiv?duos remanescentes. O primer que obteve a maior porcentagem de locos polim?rficos (LP%) foi UBC 841 (16,36%), j? o primer que teve a menor LP% foi UBC 827 (8,18%). No estudo de diversidade e estrutura gen?tica dos indiv?duos de uma popula??o natural (regenerantes = 62, jovens = 20, adultos = 19) foram utilizados sete iniciadores ISSR que permitiram a visualiza??o de 93 locos, com 100% de polimorfismo. Os regenerantes foram os que mais se destacaram em rela??o ? diversidade gen?tica (He = 0,411 e Ho = 0,599), seguido pelos jovens (He = 0,394 e Ho = 0,579) e adultos (He = 0,267 e Ho = 0,427). A AMOVA mostrou que a maior varia??o gen?tica ocorre dentro dos est?gios de vida (93,42%) quando comparado entre eles (6,58%). O dendograma (UPGMA), com base na identidade gen?tica de Nei, mostrou maior semelhan?a genot?pica entre os jovens e regenerantes (0,979). No teste de hip?tese para o gargalo gen?tico (bottleneck) foi observado elevado n?mero de locos com excesso de heterozigosidade para os dois modelos utilizados (IAM = 92 e SMM = 91), indicando redu??o do tamanho efetivo populacional. Todos os est?gios de desenvolvimento apresentaram estrutura??o gen?tica espacial (EGE), com valores de coancestrias positivos e significativos, sendo os valores de Sp de 0,04 para os regenerantes, 0,093 para os jovens, 0,15 para os adultos e 0,53 para a popula??o geral. Essa EGE ocorre, provavelmente, devido ? dispers?o restrita de sementes

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