Catheter-associated urinary tract infection (CAUTI) is one of the most common nosocomial infections and is caused by a range of different uropathogens, particularly by uropathogenic Escherichia coli (UPEC). Amongst the different virulence factors, biofilm formation and bacterial aggregation, often mediated by cell surface structures such as fimbriae, are common traits among uropathogens that cause CAUTI. In this study, a collection of UPEC isolates were screened for virulence genes and phenotypes associated with urinary tract infections such as biofilm formation and mannose-sensitive haemagglutination. Two strains, E. coli MS2027 (which formed a strong biofilm) and E. coli M184 (which aggregated strongly) were analysed in detail to determine the molecular mechanisms associated with these phenotypes. Transposon mutagenesis of E. coli MS2027 identified type 3 fimbriae as the factor responsible for its strong biofilm growth. Further screening revealed the presence of type 3 fimbriae in uropathogenic Citrobacter freundii, Citrobacter koseri, Klebsiella oxytoca, Klebsiella pneumoniae and other E. coli. Phylogenetic analysis of the type 3 fimbrial (mrkABCD) genes from these strains revealed they clustered into five distinct clades (A-E) ranging from one to twenty-three members. The majority of the sequences grouped in clade A, which was represented by the mrk gene cluster from the genome sequenced K. pneumoniae strain MGH78578. We demonstrated that type 3 fimbriae are functionally expressed by different Gram negative nosocomial pathogens and present evidence to suggest that they contribute significantly to catheter colonisation. The type 3 fimbrial genes from E. coli MS2027 were found to be located on a conjugative plasmid. Sequencing and annotation revealed that this 42,644 bp plasmid, named pMAS2027, contains 58 putative genes. Bioinformatic analysis identified pMAS2027 as an incompatibility X (IncX1) plasmid. Plasmid pMAS2027 contained genes encoding two important virulence factors, type 3 fimbriae and a type IV secretion (T4S) system. The biofilm ability was solely based on the expression of type 3 fimbriae and not the T4S system. The T4S system, however, accounted for the conjugative ability of pMAS2027. Differential tagging with fluorescent reporter genes demonstrated conjugative transfer of pMAS2027 between cells during biofilm growth. Finaly, transposon mutagenesis of E. coli M184 revealed a number of putative genes potentially responsible for bacterial aggregation. Of these, genes involved in the synthesis of the enterobacterial common antigen (ECA) were shown to be associated with an aggregation phenotype.

Catheter-associated urinary tract infection (CAUTI) is one of the most common nosocomial infections and is caused by a range of different uropathogens, particularly by uropathogenic Escherichia coli (UPEC). Amongst the different virulence factors, biofilm formation and bacterial aggregation, often mediated by cell surface structures such as fimbriae, are common traits among uropathogens that cause CAUTI. In this study, a collection of UPEC isolates were screened for virulence genes and phenotypes associated with urinary tract infections such as biofilm formation and mannose-sensitive haemagglutination. Two strains, E. coli MS2027 (which formed a strong biofilm) and E. coli M184 (which aggregated strongly) were analysed in detail to determine the molecular mechanisms associated with these phenotypes. Transposon mutagenesis of E. coli MS2027 identified type 3 fimbriae as the factor responsible for its strong biofilm growth. Further screening revealed the presence of type 3 fimbriae in uropathogenic Citrobacter freundii, Citrobacter koseri, Klebsiella oxytoca, Klebsiella pneumoniae and other E. coli. Phylogenetic analysis of the type 3 fimbrial (mrkABCD) genes from these strains revealed they clustered into five distinct clades (A-E) ranging from one to twenty-three members. The majority of the sequences grouped in clade A, which was represented by the mrk gene cluster from the genome sequenced K. pneumoniae strain MGH78578. We demonstrated that type 3 fimbriae are functionally expressed by different Gram negative nosocomial pathogens and present evidence to suggest that they contribute significantly to catheter colonisation. The type 3 fimbrial genes from E. coli MS2027 were found to be located on a conjugative plasmid. Sequencing and annotation revealed that this 42,644 bp plasmid, named pMAS2027, contains 58 putative genes. Bioinformatic analysis identified pMAS2027 as an incompatibility X (IncX1) plasmid. Plasmid pMAS2027 contained genes encoding two important virulence factors, type 3 fimbriae and a type IV secretion (T4S) system. The biofilm ability was solely based on the expression of type 3 fimbriae and not the T4S system. The T4S system, however, accounted for the conjugative ability of pMAS2027. Differential tagging with fluorescent reporter genes demonstrated conjugative transfer of pMAS2027 between cells during biofilm growth. Finaly, transposon mutagenesis of E. coli M184 revealed a number of putative genes potentially responsible for bacterial aggregation. Of these, genes involved in the synthesis of the enterobacterial common antigen (ECA) were shown to be associated with an aggregation phenotype.

Thesis (Ph.D.)--University of Melbourne, School of Physics, 2003. / Typescript (photocopy). Includes bibliographical references (leaves 121-132).

Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). "16 November 2006." Includes bibliographical references (leaves 99-112). Also available via the World Wide Web.

The Czech conjugaion is typical of relative instability of particular conjugation paradigma. The aim of this thesis is to examine a systematic transitiv of verbs of one class to another class on the one hand and to examine fluctuation of chosen verbs between different patterns, to determine topical forms of these transitions and fluctuation and finally to determine the direction of this transitiv, i. e. identificate more frequently used paradigma for each transitiv and fluctuation on the other hand. De facto it is the eximinaton of stability of verbal conjugation, with the aim to identify stronger or more dominant paradigma. A typice example of the transitiv is the migration of verbs from first class (mazat) to fifth class (dělat), a typice example of fluctuation is the second class, in which individual verbs tend to fluctuate between different patterns. Neither the fluctuation nor the transitiv do not happen at the same level in all morphological forms: the aim of this thesis is to identify these forms and determine the level and frequency of fluctuations and transitions in the contemporary usage from the corpus data (ČNK) and data obtained from questionnaires. This work is dividend into a theoretical part and a practical part. In the theoretical part we discuss verbal categories and classification of verbs based od them. Besides the classical Czech systém, we describe also one-stem systém (Townsend 2000, section 2.2), then we describe individual classes, patterns and also transitions and fluctuations esistin in the Czech verbal systém. The practical part is dedicated to verification of described tendencies. We proceed along two lines: on the one hand we use data from ČNK and on the other hand, (led by an effort to reach even spoken, not only written languages, in which the corpus SYN is based), the author made a questionnaire to which 85 people responded. The results of both examinations overlap.

Flat dendrimers, consisting of a hexavalent aromatic core and rigid ethynyl units locked in place by ether connections were developed based upon the divergent synthetic method. Alternating functional groups were adopted on each site of the hexa-substituted benzene, in order to avoid undesired cyclization pathways. The flat structures of conjugated dendrimers would allow investigation on the discotic liquid crystal properties. In addition, these ethylnyl dendrimers are expected to show directed energy and electron transfer with a highly conjugated system, and thus are effective in the preparation of photoreactive materials such as electronic sensors or light harvesting materials. Conjugated polycyclic aromatic hydrocarbons, consisting of naphthalene, anthracene, pyrene, and phenanthrene groups connected via 1,3,5-triethynylbenzene cores, were synthesized. These molecules exhibited luminescence properties and the π-complexation with a mercury trifunctional lewis acid are expected to enhance the phosphorescence in the presence of the heavy metal due to the spin-orbit coupling. Besides, owing to the presence of heavy metal atom in the Au (I) complexes linked by s-bonded triethynyltriphenylene luminophore, the phosphorescence occurs from a metal-centered emission. The conjugated organic luminophores have been developed to produce excellent quantum efficiencies, brightness, and long lifetimes.

As vacinas conjugadas contra Streptococcus pneumoniae mostram-se eficazes na redução da doença pneumocócica, no entanto depois de sua introdução tem se verificado a substituição de sorotipos. Para evitar estes problemas o emprego de proteínas da própria bactéria como carreadoras tem sido usado. Neste trabalho a PspA foi conjugada ao sorotipo 6B de S. pneumoniae por dois métodos de conjugação. Inicialmente a PspA clado 1 e 3 foram purificadas, recuperando as proteínas com mais de 90% de pureza. A conjugação intermediada pelo agente ativador cloreto de 4-(4,6-dimetoxi-1,3,5-triazin-2-il-)-4-metilmorfolino (DMT-MM) permitiu rendimentos de Ps entre 20 e 30%, no entanto este tipo de conjugado não foi imunogênico resultando na não indução de anticorpos anti-PspA. Por outro lado a conjugação por aminação redutiva possibilitou obter rendimentos de Ps entre 50 e 60% e os conjugados induziram elevados títulos de anticorpos anti-PspA em camundongos Balb/c, que foram capazes de promover a fagocitose da bactéria; no entanto, a resposta de anticorpos anti-Ps 6B foi baixa. / Conjugate vaccines against Streptococcus pneumonaie have had an important public health benefit; nevertheless after its introduction it has been observed a serotype replacement. To solve this problems conjugate vaccines using pneumococcal surface proteins as carriers has been studied. In this work, Pneumococal surface protein A (PspA) was employed as a carrier protein, conjugated to serotype 6B. Initially PspA clade 1 and PspA clade 3 were purified; both proteins were recovered with more than 90% purity. The conjugation mediated by the activating agent 4- (4,6-dimethoxy-1,3,5-triazin-2-yl -) - 4-methylmorpholine chloride(DMT-MM) allowed Ps yields between 20 and 30%, however this conjugation chemistry had a negative impact on the immunogenicity of the protein. On the other hand conjugation by reductive amination led to Ps yields between 50 and 60% and induced high anti-PspA antibodies titers in Balb /c mice that were able to promote phagocytosis of the bacterium; however, polysaccharide 6B induced low antibody titers.

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京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18293号 / 工博第3885号 / 新制||工||1596(附属図書館) / 31151 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 中條 善樹, 教授 秋吉 一成, 教授 赤木 和夫 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM