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Molecular typing and evolutionary relationships of Salmonella enterica serovar TyphiOctavia, Sophie, Biotechnology & Biomolecular Sciences, Faculty of Science, UNSW January 2008 (has links)
The evolutionary relationship between Salmonella enterica serovar Typhi, other typhoid-like enteric fever causing serovars and 10 non-Typhoid serovars from S. enterica subspecies I, could not be determined by comparative nucleotide sequences of six genes. Phylogenetic analyses of the dataset showed that the genes of interest underwent frequent recombination, suggesting a low level of clonality within subspecies I of S. enterica. To establish the evolutionary relationships within serovar Typhi, genome-wide Single Nucleotide Polymorphism (SNP) was explored as a marker for both typing purposes and phylogenetic analysis. Thirty eight SNPs were typed in 73 global Typhi isolates, including 18 isolates expressing the special flagellar antigen z66, using restriction enzyme digestion method. The isolates were differentiated into 23 SNP profiles and grouped into four distinct clusters. The z66 isolates were divided into four SNP profiles and were all grouped into one cluster, suggesting a single origin. An alternative SNP typing method using the hairpin real time PCR assay was investigated to type four additional SNPs, termed as biallelic polymorphisms (BiP). These BiPs were found to classify 481 global Typhi isolates into five major clusters (Roumagnac et al., 2006). Typing four BiPs resulted in the identification of four additional SNP profiles. We proposed nine SNPs were required to type Typhi isolates into 13 subclusters for global epidemiology. An enzymatic-based method using CelI nuclease was evaluated to discover more SNPs from other Typhi genomes. The efficiency of the CelI was shown to be unsatisfactory and we were unable to demonstrate the effectiveness of the proposed method. Nine Variable Number of Tandem Repeats (VNTRs) were typed in the 73 Typhi isolates using fluorescent-labelled universal primers, and analysed on an automated DNA sequencer. Five isolates were unable to give PCR products in one or more VNTR loci. Nine VNTRs could differentiate 68 Typhi isolates into 65 MLVA profiles, suggesting a higher discriminating power than SNP typing. SNPs were shown to be a more appropriate marker for phylogenetic tracing for Typhi while VNTRs were highly discriminating but could not be used to establish the evolutionary relationships of diverse Typhi isolates.
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Molecular typing and evolutionary relationships of Salmonella enterica serovar TyphiOctavia, Sophie, Biotechnology & Biomolecular Sciences, Faculty of Science, UNSW January 2008 (has links)
The evolutionary relationship between Salmonella enterica serovar Typhi, other typhoid-like enteric fever causing serovars and 10 non-Typhoid serovars from S. enterica subspecies I, could not be determined by comparative nucleotide sequences of six genes. Phylogenetic analyses of the dataset showed that the genes of interest underwent frequent recombination, suggesting a low level of clonality within subspecies I of S. enterica. To establish the evolutionary relationships within serovar Typhi, genome-wide Single Nucleotide Polymorphism (SNP) was explored as a marker for both typing purposes and phylogenetic analysis. Thirty eight SNPs were typed in 73 global Typhi isolates, including 18 isolates expressing the special flagellar antigen z66, using restriction enzyme digestion method. The isolates were differentiated into 23 SNP profiles and grouped into four distinct clusters. The z66 isolates were divided into four SNP profiles and were all grouped into one cluster, suggesting a single origin. An alternative SNP typing method using the hairpin real time PCR assay was investigated to type four additional SNPs, termed as biallelic polymorphisms (BiP). These BiPs were found to classify 481 global Typhi isolates into five major clusters (Roumagnac et al., 2006). Typing four BiPs resulted in the identification of four additional SNP profiles. We proposed nine SNPs were required to type Typhi isolates into 13 subclusters for global epidemiology. An enzymatic-based method using CelI nuclease was evaluated to discover more SNPs from other Typhi genomes. The efficiency of the CelI was shown to be unsatisfactory and we were unable to demonstrate the effectiveness of the proposed method. Nine Variable Number of Tandem Repeats (VNTRs) were typed in the 73 Typhi isolates using fluorescent-labelled universal primers, and analysed on an automated DNA sequencer. Five isolates were unable to give PCR products in one or more VNTR loci. Nine VNTRs could differentiate 68 Typhi isolates into 65 MLVA profiles, suggesting a higher discriminating power than SNP typing. SNPs were shown to be a more appropriate marker for phylogenetic tracing for Typhi while VNTRs were highly discriminating but could not be used to establish the evolutionary relationships of diverse Typhi isolates.
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Molecular Typing of Giardia lamblia in Humans and Dogs and Evidence for Sexual RecombinationCooper, Margarethe January 2006 (has links)
Giardia lamblia is a eukaryotic parasite that causes diarrhea in humans worldwide. Diarrheal diseases cause stunting and mental retardation in children in developing nations, therefore it is important to understand the molecular epidemiology of G. lamblia. Compounding this, it is not clear if companion animals such as dogs contribute to infections in humans through zoonotic transmission. The genotypes of G. lamblia that have been found in humans are A1, A2 and B, while those in dogs have been on rare occasions all three human genotypes, but largely C and D, which have only been reported in dogs and appear to be species-specific. The molecular epidemiology of G. lamblia in humans and dogs was assessed in an endemic region of Lima, Peru. With one exception, dogs were found to harbor the C and D dog genotypes of G. lamblia. A single family dog was found to harbor a human genotype of G. lamblia. A2 and B genotypes of G. lamblia, but not A1, were found in humans in the endemic region. Previous literature reported that A2 and B typing within genotype tools were available, however the A2 samples from the endemic region could not be distinguished from one another through nucleotide polymorphism sequence analysis. A molecular typing technique was developed to type A2 samples. The extensive sequence analysis performed on two chromosomes of G. lamblia, yielded different phylogenetic tree groupings for the same samples. This lead to algorithmic analysis, which demonstrated a significantly high probability that meiotic recombination is occurring in the A2 samples of G. lamblia. As G. lamblia is largely believed to be asexual, the conclusion of doctoral research performed in this study yielded controversial, yet significant evidence that sex in G. lamblia A2 genotype samples is indeed occurring.
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Molecular typing and evolution of Salmonella enterica serovar TyphimuriumHu, Honghua January 2005 (has links)
Salmonella enterica serovar Typhimurium is a common cause of salmonellosis among humans and animals worldwide. In Australia, Typhimurium is responsible for over half of the salmonellosis cases. The Anderson phage-typing scheme is the primary means of long-term surveillance of Typhimurium outbreak isolates, and has played an important role in epidemiology. However, there exist quite a number of strains of Typhimurium that cannot be defined by the phage-typing scheme. Furthermore, the knowledge of evolutionary relationships among isolates of different phage types is still very limited and the genetic basis of phage type variation remains largely unknown. To address these issues, this study focused on molecular typing and evolution of Typhimurium. Fluorescent amplified-fragment length polymorphism (AFLP) was applied to 46 Typhimurium isolates comprising nine phage types in Australia using the restriction enzymes MseI and EcoRI and MseI +1 / EcoRI +1 primer pair combinations. The selected phage types, DT9, DT135, DT64, DT44, DT126, DT12a, DT1, DT141 and DT108, have been dominant or frequent phage types in animal and human infections in Australia in recent years. AFLP in the present study showed a very good discrimination power with Simpson index of diversity of 0.98, 35 different AFLP patterns were observed in the 46 isolates studied. The tree based on AFLP patterns showed good correlation with phage type, grouped most Typhimurium isolates by phage type, and differentiated all nine phage types. Furthermore, 84 phage-type specific polymorphic AFLP fragments, for which presence or absence correlated with phage type (including 25 with one exception to phage-type specificity) were observed in the 46 strains studied. Eighteen phage-type specific AFLP fragments were cloned and sequenced. Sixteen are of known genes or have a homologue in the databases. It was found a predominance of phage and plasmid genes rather than mutational changes in the AFLP fragments studied. Of the 18 cloned and sequenced AFLP fragments, only four relate to mutational changes in the S. enterica chromosome, the other 14 comprise DNA of mobile elements: nine are phage related, three are plasmid related and two are gain of DNA from unknown origin. Twelve of the 18 sequenced phage-type specific AFLP markers are polymorphic because the DNA is present or absent as indicated by Southern hybridization. Two of these markers were successfully used in preliminary PCR-based typing of 30 DT9 and 29 DT135 isolates from worldwide collections. 27 of the 30 DT9 isolates and all DT135 isolates tested were correctly categorized. The results implied a good potential to use the sequence of these fragments as the basis for a multiplex PCR or a microarray based molecular �phage� typing method for Typhimurium. This thesis also studied the molecular evolutionary relationships among the same set of 46 Typhimurium isolates using mutational changes detected by AFLP, or analysis of intergenic regions and their flanking genes in genome sequences. The complete genome sequence of Typhimurium LT2 was analysed by computer modelled AFLP. The polymorphic AFLP fragments, which matched with the modelled LT2 AFLP fragments, were amplified and sequenced by LT2 genome based primers to determine the changes. Forty-nine intergenic regions with higher pairwise differences between LT2 and Typhi CT18 were amplified and sequenced using LT2 genome based primers for one isolate of each phage type. 51 polymorphic sites were detected consisting of 18 in AFLP fragments and 33 in intergenic regions or their flanking genes. PCR-RFLP (restriction fragment length polymorphism) and SNaPshot were used to further investigate the distribution of the single nucleotide polymorphisms (SNPs) detected in intergenic regions in all isolates studied. Of the 18 mutational changes detected in AFLP fragments, eight were indels (insertions / deletions) and ten single base substitutions. Of the eight indels, four were in genes, three in intergenic regions, and one covered adjacent intergenic and coding regions. The four indels in genes all caused frameshift mutations, including three single base indels and one 19 bp deletion. Of the ten substitutions, one was in an intergenic region and nine in genes comprising three synonymous and six non-synonymous substitutions. Of the 33 polymorphic sites detected from sequences of 23 intergenic regions and their flanking genes, one was IS200 insertion and 32 single nucleotide polymorphisms (SNPs), of which 30 were single base substitutions and two were single base indels. Nine of the 33 variations were found in the flanking genes, which were all single base substitutions comprising four synonymous, four non-synonymous substitutions and one non-sense mutation. More non-synonymous than synonymous substitutions were found for those in coding regions within Typhimurium, indicating that slightly deleterious intraspecies mutations can be fixed within clones, such as various lineages of Typhimurium. The 51 polymorphic sites, which were inferred from sequences of both mutation related AFLP fragments, and intergenic regions and their flanking genes, gave a single phylogenetic tree of the 46 Typhimurium isolates studied. All sequences involved were compared with the homologous sequences in the available S. enterica genome sequences for serovars Typhi, Paratyphi A, Gallinarum, Enteritidis and Pullorum and this enabled the determination of the direction of the mutational changes in the isolates studied and the root of the phylogenetic tree. There were only two events inferred to have occurred twice, the remaining 49 polymorphisms can be explained by a single event. The data indicated that Typhimurium has a very strong clonal structure with a very low level of recombination over the time for diversification of Typhimurium as majority of clonal variations are from point mutations rather than recombination. The phylogenetic tree based on mutational changes showed that most Typhimurium isolates of a given phage type are in the same evolutionary group, but that some phage types appear to have arisen more than once. Comparison of the phylogenetic tree with AFLP data gave examples of unrelated isolates of a given phage type having common AFLP fragments comprising plasmid or phage genes, supporting the view that phage type can be determined by presence of specific phages or plasmids. The mutation-based tree showed that six of the nine phage types studied appeared to have a single origin, at least for the isolates studied. It also found that DT1 and DT44 had two independent origins even for the limited set of strains used. The distribution of DT12a isolates into two groups could be explained that the group of three DT12a isolates were derived from the other group of four DT12a isolates, where the root of the tree might be. The data also confirmed that DT64 arose from DT9. The phylogenetic tree that was generated based on essentially mutational changes provides clear relationships of the closely related Typhimurium isolates with high level of consistency and reasonable confidence. This study provided one of the few analyses of relationships of isolates within a clone. Matching actual AFLP with computer modeled AFLP and sequencing intergenic regions provide very good new strategies to identify mutational polymorphisms and to study the molecular evolutionary relationships in the closely related isolates.
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Molecular typing and evolution of Salmonella enterica serovar TyphimuriumHu, Honghua January 2005 (has links)
Salmonella enterica serovar Typhimurium is a common cause of salmonellosis among humans and animals worldwide. In Australia, Typhimurium is responsible for over half of the salmonellosis cases. The Anderson phage-typing scheme is the primary means of long-term surveillance of Typhimurium outbreak isolates, and has played an important role in epidemiology. However, there exist quite a number of strains of Typhimurium that cannot be defined by the phage-typing scheme. Furthermore, the knowledge of evolutionary relationships among isolates of different phage types is still very limited and the genetic basis of phage type variation remains largely unknown. To address these issues, this study focused on molecular typing and evolution of Typhimurium. Fluorescent amplified-fragment length polymorphism (AFLP) was applied to 46 Typhimurium isolates comprising nine phage types in Australia using the restriction enzymes MseI and EcoRI and MseI +1 / EcoRI +1 primer pair combinations. The selected phage types, DT9, DT135, DT64, DT44, DT126, DT12a, DT1, DT141 and DT108, have been dominant or frequent phage types in animal and human infections in Australia in recent years. AFLP in the present study showed a very good discrimination power with Simpson index of diversity of 0.98, 35 different AFLP patterns were observed in the 46 isolates studied. The tree based on AFLP patterns showed good correlation with phage type, grouped most Typhimurium isolates by phage type, and differentiated all nine phage types. Furthermore, 84 phage-type specific polymorphic AFLP fragments, for which presence or absence correlated with phage type (including 25 with one exception to phage-type specificity) were observed in the 46 strains studied. Eighteen phage-type specific AFLP fragments were cloned and sequenced. Sixteen are of known genes or have a homologue in the databases. It was found a predominance of phage and plasmid genes rather than mutational changes in the AFLP fragments studied. Of the 18 cloned and sequenced AFLP fragments, only four relate to mutational changes in the S. enterica chromosome, the other 14 comprise DNA of mobile elements: nine are phage related, three are plasmid related and two are gain of DNA from unknown origin. Twelve of the 18 sequenced phage-type specific AFLP markers are polymorphic because the DNA is present or absent as indicated by Southern hybridization. Two of these markers were successfully used in preliminary PCR-based typing of 30 DT9 and 29 DT135 isolates from worldwide collections. 27 of the 30 DT9 isolates and all DT135 isolates tested were correctly categorized. The results implied a good potential to use the sequence of these fragments as the basis for a multiplex PCR or a microarray based molecular �phage� typing method for Typhimurium. This thesis also studied the molecular evolutionary relationships among the same set of 46 Typhimurium isolates using mutational changes detected by AFLP, or analysis of intergenic regions and their flanking genes in genome sequences. The complete genome sequence of Typhimurium LT2 was analysed by computer modelled AFLP. The polymorphic AFLP fragments, which matched with the modelled LT2 AFLP fragments, were amplified and sequenced by LT2 genome based primers to determine the changes. Forty-nine intergenic regions with higher pairwise differences between LT2 and Typhi CT18 were amplified and sequenced using LT2 genome based primers for one isolate of each phage type. 51 polymorphic sites were detected consisting of 18 in AFLP fragments and 33 in intergenic regions or their flanking genes. PCR-RFLP (restriction fragment length polymorphism) and SNaPshot were used to further investigate the distribution of the single nucleotide polymorphisms (SNPs) detected in intergenic regions in all isolates studied. Of the 18 mutational changes detected in AFLP fragments, eight were indels (insertions / deletions) and ten single base substitutions. Of the eight indels, four were in genes, three in intergenic regions, and one covered adjacent intergenic and coding regions. The four indels in genes all caused frameshift mutations, including three single base indels and one 19 bp deletion. Of the ten substitutions, one was in an intergenic region and nine in genes comprising three synonymous and six non-synonymous substitutions. Of the 33 polymorphic sites detected from sequences of 23 intergenic regions and their flanking genes, one was IS200 insertion and 32 single nucleotide polymorphisms (SNPs), of which 30 were single base substitutions and two were single base indels. Nine of the 33 variations were found in the flanking genes, which were all single base substitutions comprising four synonymous, four non-synonymous substitutions and one non-sense mutation. More non-synonymous than synonymous substitutions were found for those in coding regions within Typhimurium, indicating that slightly deleterious intraspecies mutations can be fixed within clones, such as various lineages of Typhimurium. The 51 polymorphic sites, which were inferred from sequences of both mutation related AFLP fragments, and intergenic regions and their flanking genes, gave a single phylogenetic tree of the 46 Typhimurium isolates studied. All sequences involved were compared with the homologous sequences in the available S. enterica genome sequences for serovars Typhi, Paratyphi A, Gallinarum, Enteritidis and Pullorum and this enabled the determination of the direction of the mutational changes in the isolates studied and the root of the phylogenetic tree. There were only two events inferred to have occurred twice, the remaining 49 polymorphisms can be explained by a single event. The data indicated that Typhimurium has a very strong clonal structure with a very low level of recombination over the time for diversification of Typhimurium as majority of clonal variations are from point mutations rather than recombination. The phylogenetic tree based on mutational changes showed that most Typhimurium isolates of a given phage type are in the same evolutionary group, but that some phage types appear to have arisen more than once. Comparison of the phylogenetic tree with AFLP data gave examples of unrelated isolates of a given phage type having common AFLP fragments comprising plasmid or phage genes, supporting the view that phage type can be determined by presence of specific phages or plasmids. The mutation-based tree showed that six of the nine phage types studied appeared to have a single origin, at least for the isolates studied. It also found that DT1 and DT44 had two independent origins even for the limited set of strains used. The distribution of DT12a isolates into two groups could be explained that the group of three DT12a isolates were derived from the other group of four DT12a isolates, where the root of the tree might be. The data also confirmed that DT64 arose from DT9. The phylogenetic tree that was generated based on essentially mutational changes provides clear relationships of the closely related Typhimurium isolates with high level of consistency and reasonable confidence. This study provided one of the few analyses of relationships of isolates within a clone. Matching actual AFLP with computer modeled AFLP and sequencing intergenic regions provide very good new strategies to identify mutational polymorphisms and to study the molecular evolutionary relationships in the closely related isolates.
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Tipagem molecular, perfis de sensibilidade e caracterização de transcritos diferencialmente expressos durante a infecção de Cryptococcus neoformansMatsumoto, Marcelo Teruyuki [UNESP] 14 December 2006 (has links) (PDF)
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matsumoto_mt_dr_arafcf.pdf: 7554122 bytes, checksum: 0910afc354605fb9e82889bf3660ea86 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / Cryptococcus neoformans é patógeno importante, principalmente em pacientes imunocomprometidos. A principal porta de entrada deste patógeno é pela via respiratória, disseminando-se posteriormente e atingindo principalmente o sistema nervoso central, provocando a meningite criptocóccica. A primeira parte deste estudo teve como objetivos determinar, nos 106 isolados clínicos de C. neoformans obtidos de dois Estados (São Paulo e Rio de Janeiro), (1) as variedades e (2) os mating-types por PCR (Polymerase Chain Reaction), (3) analisar a diversidade genética por PCR-fingerprinting com a seqüência iniciadora específica para regiões microssatélite (GACA)4, (4) por RAPD (Random Amplification of Polymorphic DNA) com o iniciador 6 e (5) por PCR-RFLP (Restriction Fragment Length Polymorphism) do gene da fosfolipase B (PLB1) digerido com a enzima de restrição AvaI e (6) determinar a sensibilidade a quatro antifúngicos (fluconazol, itraconazol, 5-fluorocitosina e anfotericina B) seguindo o método de referência (documento M27-A2) do CLSI (Clinical and Laboratory Standards Institute). A segunda parte teve como objetivo, analisar transcritos diferencialmente expressos durante a infecção pulmonar de C. neoformans, pela técnica de RDA (Representational Difference Analysis). Entre os 106 isolados, 104 foram identificados como C. neoformans e apenas dois foram C. gattii (=C. neoformans var. gattii), todos MATa. O tipo molecular VNI (C. neoformans var. grubii, sorotipo A) foi o mais prevalente entre os isolados (97/106), seguido do tipo VNII (C. neoformans var. grubii, sorotipo A) (7/106) e VGII (C. gattii, sorotipos B ou C) (2/106) quando analisados por PCR-fingerprinting e PCR-RFLP. Homogeneidade alta foi obtida com o iniciador (GACA)4, com a maioria dos isolados apresentando correlação em torno de 0,9. Os resultados do RAPD, por sua vez, revelaram maior heterogeneidade com número maior de perfis moleculares. / Cryptococcus neoformans is an important pathogen, mainly in immunocompromised patients. The pathogen penetrates mainly by respiratory way, disseminate afterward and reach specially the central nervous system causing the cryptococcal meningitis. The first part of this study had the objective to determine, in the 106 clinical isolates of C. neoformans obtained from São Paulo and Rio de Janeiro State, (1) the varieties and (2) mating-types by PCR (Polymerase Chain Reaction), (3) analyze the genetic diversity by PCR-fingerprinting with specific primer to microsatellite regions (GACA)4, (4) by RAPD (Random Amplification of Polymorphic DNA) with primer 6 and (5) by PCR-RFLP (Restriction Fragment Length Polymorphism) of the phospholipase B gene (PLB1) digested with restriction enzyme AvaI and (6) to determine the susceptibility to four antifungal (fluconazole, itraconazole, 5-flucytosine and amphotericin B) following the reference method (document M27-A2) from CLSI (Clinical and Laboratory Standard Institute). The second part had the goal to analyze differentially expressed transcription during pulmonary infection of C. neoformans, by RDA (Representational Difference Analysis) technique. Among 106 isolates, 104 were identified as C. neoformans and only two were C. gattii (=C. neoformans var. gattii), all MATa. The molecular type VNI (C. neoformans var. grubii, serotype A) was the most prevalent among the isolates (97/106), followed by VNII (C. neoformans var. grubii, serotype A) (7/106) and VGII (C. gattii, serotypes B ou C) (2/106) when analyzed by PCR-fingerprinting and PCR-RFLP. High homogeneity was obtained with the primer (GACA)4, with most of the isolates showing correlation around 0.9. By contrast, the RAPD analysis revealed more heterogeneous with more numbers of molecular profiles.
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Determinação da diversidade bacteriana em culturas de caldo Macconkey de materiais clínicos de portadores de doença de Crohn e análise de propriedades de isolados de Escherichia coli identificados / Determination of diversity bacterial material clinical Crohn's disease patients and analysis of isolated properties Escherichia coli identifiedCarvalho, Vanessa Rafaela de [UNESP] 09 August 2016 (has links)
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Previous issue date: 2016-08-09 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Desequilíbrio na composição de espécies bacterianas (disbiose) do intestino é uma característica da doença de Crohn (DC), a mais grave das doenças inflamatórias intestinais (DII). Na disbiose da DII, há um aumento de certos grupos de bactérias, tais como as Proteobacteria, em alguns pacientes. Acredita-se que o aumento destas bactérias deve contribuir para as reações inflamatórias responsáveis pelas lesões observadas no intestino de portadores de DC e retocolite ulcerativa, ao estimular a produção de citocinas por células locais do sistema imune. Proteobacteria, um dos filos predominantes da microbiota intestinal compreende bacilos gram-negativos, dos quais Escherichia coli (E. coli) é o mais conhecido. Dada a importância de Proteobacteria como patógeno ou membro da microbiota intestinal residente humana, este trabalho teve dois objetivos: 1) Investigar a ocorrência de variação numérica na população de Proteobacteria na DC e 2) Caracterizar amostras de E. coli encontradas nesta população, em relação a propriedades de virulência. Visando o primeiro objetivo, DNA de culturas em caldo MacConkey de diferentes materiais clínicos (fezes e biópsias intestinais) de 8 controles e 9 pacientes com DC foram amplificados com primers para as regiões V6-V8 do gene que codifica a fração 16S do rRNA (16S V6-V8 rDNA) e, em seguida, sequências específicas (representando táxons bacterianos particulares) contidas nos amplicons foram separadas por temperature gradient gel electrophoresis (TGGE), definindo perfis de banda que refletem a diversidade bacteriana. O segundo objetivo compreendeu a tipagem dos isolados de E. coli destas culturas através da classificação em filogrupos (A, B1, B2 e D) da coleção de referência de E. coli (EcoR), a pesquisa de sorogrupos O25 e O83, determinação das propriedades de aderência e capacidade de produzir biofilme. Análise de 32 culturas de 9 portadores de DC e 24 culturas de 8 controles mostrou uma clara diferença no número de bandas nos perfis de TGGE dos amplicons de 16S V6-V8 rDNA. Amplicons de 8 culturas de 9 portadores de DC tinham no máximo 2 bandas, ao passo que o número de bandas em amplicons de controles tinham pelo menos 3 bandas. Uma das bandas dos casos em que havia duas bandas ou a banda única dos perfis de cultura de casos teve a mesma mobilidade do amplicon de E. coli, colocado no gel como referência da corrida. PCR para detecção de genes de O25 e O83 demonstraram que estes sorogrupos foram dominantes tanto na população de E. coli de portadores de DC como de controles (apenas um paciente controle deu resultado negativo na PCR para ambos sorogrupos). Também, a maioria das cepas de E. coli, tanto de casos como de controles pertenceu ao filogrupo B2. Resultados parciais de testes de adesão em células Hep-2 revelaram que todos os pacientes (controles ou não) apresentaram E. coli aderentes, expressando o padrão agregativo. Testes para avaliar a capacidade de formação de biofilme indicaram que isolados de E. coli das regiões proximais encontrados em controles produzem biofilme de forma mais intensa do que isolados equivalentes de portadores de DC. Como conclusão, os dados apresentados sugerem que a população intestinal de Proteobacteria em portadores de CD apresenta disbiose, associada com um aumento do número de E. coli, uma propriedade que foi determinada por TGGE e confirmada com seqüenciamento de amplicons da região V6, pela técnica Ion Torrent. Por fim, com base nos resultados de tipagem e caracterização bacteriana foi possível observar que amostras tanto de caso como de controles, não houve uma prevalência dos sorogrupos e com base nesse resultado podemos associar que ambos os grupos de estudos freqüentam de forma rotineira o mesmo ambiente hospitalar, podendo indicar um favorecimento na aquisição desses tipos bacterianos. Resultados semelhantes ocorreram com as análises dos sorogrupos, onde apenas o filogrupo D teve prevalência significativa em indivíduos controle. Em relação à produção de biofilme, as amostras encontradas na região proximal do intestino de pacientes controles produzem mais biofilmes do que amostras de portadores de DC da mesma região intestinal, indicando que a parede da mucosa intestinal serve como substrato pode influenciar na formação do biofilme. / Imbalance in intestinal bacterial composition (dysbiosis) is a hallmark of Crohn’s disease (CD), the most severe of inflammatory bowel diseases (IBD). A characteristic of IBD dysbiosis is the elevation of certain groups of bacteria such as Proteobacteria in some patients. It is believed that the augmented bacteria may contribute for the inflammatory reactions underlying the typical lesions observed in the gut of CD and ulcerative colitis patients, by stimulating the production of cytokines by local cells of the immune system. Proteobacteria, one the most prevalent bacterial phyla of the gut microbiota are Gram negative rods of which Escherichia coli (E. coli) is the most well-known member. Given the significance of Proteobacteria as pathogens or member of resident gut microbiota, this work had two purposes: 1) to investigate the occurrence of numerical variation in the population of these bacteria in CD and 2) Characterizing E. coli isolates found in this population, in search for some virulence associated properties. For the first purpose, DNA from MacConkey broth cultures of distinct clinical materials (stools and gut mucosal biopsies) of 9 CD and 8 control patients were amplified with primers for the V6 and V8 regions of the 16S ribosomal RNA gene (16S V6-V8 rDNA) and distinct gene sequences (representing particular bacterial taxa) within the amplicons were resolved by temperature gradient gel electrophoresis (TGGE), defining band profiles, which reflect the bacterial diversity. The second objective consisted in phylotyping (determining A, B1, B2 and D phylogroups), serotyping (search for O25 and O83 genes), analyzing the E. coli isolates of the cultures for adherence properties and competence to produce biofilm. Analysis of 32 cultures from the 9 CD patients and 24 cultures from 8 control subjects showed a clear case-control difference in the number of bands in the TGGE profiles of the 16S V6-V8 rDNA amplicons. Cultures from 8 of 9 CD patients had at most 2 bands, while the number of bands in the cultures from 7 of the 8 controls subjects had at least 3 bands. One of the two bands found in the cultures from CD patients had the same mobility as E. coli, put in the gelas reference for the run. PCR screening for O25 and O83 demonstrated that these serogroups were dominant among the E. coli population from both controls and CD patients (only one control subject was negative for each of these O groups). Also, most of E. coli isolates from both control and CD patients belonged to the B2 phylogroup. Partial results of bacterial adherence to Hep-2 cells revealed that all patients (controls and CD) had aggregative adherent E. coli isolates. Tests to determine the ability to produce biofilm indicated that isolates from the proximal, but not from distal region of the gut or the stools, found in controls were stronger biofilm formers than isolates from equivalent sites of CD patients. In conclusion, the data presented here reveal that intestinal population of Proteobacteria of CD patients show dysbiosis associated with the elevation of Escherichia coli and that this variation can be assessed by TGGE and confirmed by sequencing of amplicons V6 region, the technique Ion Torrent. Finally, on the basis of the bacterial typing and characterization results, was observed that samples of both the case and controls, there was a prevalence of serogroups, based on this result we can associate both study groups frequent routinely the same hospital environment and may indicate a favoring the acquisition of these bacterial types. Similar results occurred with the analysis of serogroups, where only the filogrupo D had a significant prevalence in control subjects. For biofilm production, the samples found in the proximal region of the control patients intestine produce more biofilm than DC bearing samples of the same intestinal region, indicating that the intestinal mucosa serves as a substrate may influence the formation of biofilms. / FAPESP: 2013/04475-3
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Tipagem molecular, perfis de sensibilidade e caracterização de transcritos diferencialmente expressos durante a infecção de Cryptococcus neoformans /Matsumoto, Marcelo Teruyuki. January 2006 (has links)
Orientador: Maria José Soares Mendes Giannini / Banca: Benedito Barraviera / Banca: Paulo Inácio da Costa / Banca: Célia Maria de Almeida Soares / Banca: Clarice Queico Fujimura Leite / Resumo: Cryptococcus neoformans é patógeno importante, principalmente em pacientes imunocomprometidos. A principal porta de entrada deste patógeno é pela via respiratória, disseminando-se posteriormente e atingindo principalmente o sistema nervoso central, provocando a meningite criptocóccica. A primeira parte deste estudo teve como objetivos determinar, nos 106 isolados clínicos de C. neoformans obtidos de dois Estados (São Paulo e Rio de Janeiro), (1) as variedades e (2) os mating-types por PCR (Polymerase Chain Reaction), (3) analisar a diversidade genética por PCR-fingerprinting com a seqüência iniciadora específica para regiões microssatélite (GACA)4, (4) por RAPD (Random Amplification of Polymorphic DNA) com o iniciador 6 e (5) por PCR-RFLP (Restriction Fragment Length Polymorphism) do gene da fosfolipase B (PLB1) digerido com a enzima de restrição AvaI e (6) determinar a sensibilidade a quatro antifúngicos (fluconazol, itraconazol, 5-fluorocitosina e anfotericina B) seguindo o método de referência (documento M27-A2) do CLSI (Clinical and Laboratory Standards Institute). A segunda parte teve como objetivo, analisar transcritos diferencialmente expressos durante a infecção pulmonar de C. neoformans, pela técnica de RDA (Representational Difference Analysis). Entre os 106 isolados, 104 foram identificados como C. neoformans e apenas dois foram C. gattii (=C. neoformans var. gattii), todos MATa. O tipo molecular VNI (C. neoformans var. grubii, sorotipo A) foi o mais prevalente entre os isolados (97/106), seguido do tipo VNII (C. neoformans var. grubii, sorotipo A) (7/106) e VGII (C. gattii, sorotipos B ou C) (2/106) quando analisados por PCR-fingerprinting e PCR-RFLP. Homogeneidade alta foi obtida com o iniciador (GACA)4, com a maioria dos isolados apresentando correlação em torno de 0,9. Os resultados do RAPD, por sua vez, revelaram maior heterogeneidade com número maior de perfis moleculares. / Abstract: Cryptococcus neoformans is an important pathogen, mainly in immunocompromised patients. The pathogen penetrates mainly by respiratory way, disseminate afterward and reach specially the central nervous system causing the cryptococcal meningitis. The first part of this study had the objective to determine, in the 106 clinical isolates of C. neoformans obtained from São Paulo and Rio de Janeiro State, (1) the varieties and (2) mating-types by PCR (Polymerase Chain Reaction), (3) analyze the genetic diversity by PCR-fingerprinting with specific primer to microsatellite regions (GACA)4, (4) by RAPD (Random Amplification of Polymorphic DNA) with primer 6 and (5) by PCR-RFLP (Restriction Fragment Length Polymorphism) of the phospholipase B gene (PLB1) digested with restriction enzyme AvaI and (6) to determine the susceptibility to four antifungal (fluconazole, itraconazole, 5-flucytosine and amphotericin B) following the reference method (document M27-A2) from CLSI (Clinical and Laboratory Standard Institute). The second part had the goal to analyze differentially expressed transcription during pulmonary infection of C. neoformans, by RDA (Representational Difference Analysis) technique. Among 106 isolates, 104 were identified as C. neoformans and only two were C. gattii (=C. neoformans var. gattii), all MATa. The molecular type VNI (C. neoformans var. grubii, serotype A) was the most prevalent among the isolates (97/106), followed by VNII (C. neoformans var. grubii, serotype A) (7/106) and VGII (C. gattii, serotypes B ou C) (2/106) when analyzed by PCR-fingerprinting and PCR-RFLP. High homogeneity was obtained with the primer (GACA)4, with most of the isolates showing correlation around 0.9. By contrast, the RAPD analysis revealed more heterogeneous with more numbers of molecular profiles. / Doutor
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Determinação da diversidade bacteriana em culturas de caldo Macconkey de materiais clínicos de portadores de doença de Crohn e análise de propriedades de isolados de Escherichia coli identificadosCarvalho, Vanessa Rafaela de January 2016 (has links)
Orientador: Josias Rodrigues / Resumo: Desequilíbrio na composição de espécies bacterianas (disbiose) do intestino é uma característica da doença de Crohn (DC), a mais grave das doenças inflamatórias intestinais (DII). Na disbiose da DII, há um aumento de certos grupos de bactérias, tais como as Proteobacteria, em alguns pacientes. Acredita-se que o aumento destas bactérias deve contribuir para as reações inflamatórias responsáveis pelas lesões observadas no intestino de portadores de DC e retocolite ulcerativa, ao estimular a produção de citocinas por células locais do sistema imune. Proteobacteria, um dos filos predominantes da microbiota intestinal compreende bacilos gram-negativos, dos quais Escherichia coli (E. coli) é o mais conhecido. Dada a importância de Proteobacteria como patógeno ou membro da microbiota intestinal residente humana, este trabalho teve dois objetivos: 1) Investigar a ocorrência de variação numérica na população de Proteobacteria na DC e 2) Caracterizar amostras de E. coli encontradas nesta população, em relação a propriedades de virulência. Visando o primeiro objetivo, DNA de culturas em caldo MacConkey de diferentes materiais clínicos (fezes e biópsias intestinais) de 8 controles e 9 pacientes com DC foram amplificados com primers para as regiões V6-V8 do gene que codifica a fração 16S do rRNA (16S V6-V8 rDNA) e, em seguida, sequências específicas (representando táxons bacterianos particulares) contidas nos amplicons foram separadas por temperature gradient gel electrophores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Imbalance in intestinal bacterial composition (dysbiosis) is a hallmark of Crohn’s disease (CD), the most severe of inflammatory bowel diseases (IBD). A characteristic of IBD dysbiosis is the elevation of certain groups of bacteria such as Proteobacteria in some patients. It is believed that the augmented bacteria may contribute for the inflammatory reactions underlying the typical lesions observed in the gut of CD and ulcerative colitis patients, by stimulating the production of cytokines by local cells of the immune system. Proteobacteria, one the most prevalent bacterial phyla of the gut microbiota are Gram negative rods of which Escherichia coli (E. coli) is the most well-known member. Given the significance of Proteobacteria as pathogens or member of resident gut microbiota, this work had two purposes: 1) to investigate the occurrence of numerical variation in the population of these bacteria in CD and 2) Characterizing E. coli isolates found in this population, in search for some virulence associated properties. For the first purpose, DNA from MacConkey broth cultures of distinct clinical materials (stools and gut mucosal biopsies) of 9 CD and 8 control patients were amplified with primers for the V6 and V8 regions of the 16S ribosomal RNA gene (16S V6-V8 rDNA) and distinct gene sequences (representing particular bacterial taxa) within the amplicons were resolved by temperature gradient gel electrophoresis (TGGE), defining band profiles, which reflect the bact... (Complete abstract click electronic access below) / Mestre
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Studies on mycobacterium avium subsp. paratuberculosis: genotypic and phenotypic variationsGhadiali, Alifiya H. 18 March 2005 (has links)
No description available.
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