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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Detection of Actinobacillus Pleuropneumoniae and Identification of Serotypes 1, 2, and 8 by Multiplex Polymerase Chain Reaction

Schuchert, Jennifer Ann 30 August 2002 (has links)
Traditional immunological assays used to serotype Actinobacillus pleuropneumoniae have been problematic due to cross- reactivity between serotypes, particularly serotypes 6 and 8. To avoid these serological cross-reactions, a multiplex PCR assay was developed to detect A. pleuropneumoniae and identify serotypes 1, 2, and 8. Primers specific to the conserved capsular polysaccharide export region of A. pleuropneumoniae serotype 5 amplified a 880 bp fragment in all serotypes excluding serotype 4 or a 489 bp DNA fragment in all serotypes including serotype 4. Primers specific to the capsular polysaccharide biosynthesis regions of A. pleuropneumoniae serotypes 1, 2, and 8 amplified a 1.6 kb, a 1.7 kb, and 970 bp fragment in the respective serotype. This PCR assay detects A. pleuropneumoniae and identifies serotypes 1, 2, and 8. / Master of Science
2

Detection and Identification of Acinobacillus pleuropneumoniae serotype 5 by multiplex Polymerase Chain Reaction

Lo, Terry 25 August 1997 (has links)
Traditional serologic assays of Actinobacillus pleuropeumoniae often have problems with cross-reactivity. To avoid the complications of antibody-antigen reactions, a PCR assay was developed to detect Actinobacillus pleuropneumoniae and identify serotype 5 strains. Primers specific to the conserved capsular export region of A. pleuropneumoniae amplified a 0.7 kb DNA band in all strains with the exception of serotype 4. A second set of primers specific to the unique capsular biosynthesis region of serotype 5 amplified a unique 1.1 kb band for serotype 5 only. The sensitivity of this assay was determined to be less than 100 colony forming units. This PCR assay enables us to detect A. pleuronpeumoniae and definitively distinguishes serotype 5 strains from other serotyes. / Master of Science
3

Sensibilidade a antimicrobianos e sorotipos de Streptococcus pneumoniae isolados de portadores e de indivÃduos com infecÃÃo sistÃmica em Fortaleza, Brasil. / Antibiotic Resistance and Serotypes of Streptococcus pneumoniae Isolated from Carriage and individuals with Sistemic Infection in Fortaleza, Brazil.

Bruno Jaegger Laranjeira 10 February 2010 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O Streptococcus (S.) pneumoniae à considerado como o principal agente causador de morbidade e mortalidade em crianÃas menores de cinco anos de idade. Todas as doenÃas pneumocÃcicas comeÃam com o estabelecimento da colonizaÃÃo do S. pneumoniae na nasofaringe, podendo progredir para doenÃa invasiva se as barreiras naturais forem cruzadas. Nas Ãltimas dÃcadas, o aumento do nÃmero de cepas de S. pneumoniae resistentes à antibiÃticos β-lactÃmicos e a outras classes de antimicrobianos tem dificultado o tratamento da infecÃÃo pneumocÃcica. Atualmente cerca de 13 sorotipos de S. pneumoniae respondem por mais de 85% dos isolados invasivos. A vacina pneumocÃcica polissacarÃdica conjugada 7-valente tem sido amplamente recomendada para crianÃas menores de cinco anos. Os objetivos desse estudo foram determinar a prevalÃncia de S. pneumoniae em crianÃas portadoras, a frequÃncia de isolados de S. pneumoniae de indivÃduos com infecÃÃo sistÃmica, o perfil de sensibilidade a antimicrobianos e os sorotipos mais comuns, em Fortaleza, Brasil. Os isolados de portadores foram recuperados a partir de swabs de nasofaringe de crianÃas usuÃrias de creches, enquanto que os isolados de infecÃÃo sistÃmica foram cedidos pelo LACEN-CE. Foram realizadas as ConcentraÃÃes InibitÃrias MÃnimas (CIM) para penicilina e ceftriaxona para todos os isolados, e levofloxacina apenas para os isolados de nasofaringe. Os pontos de corte das CIM foram determinados de acordo com o CLSI (2007). As sorotipagens dos isolados sistÃmicos foram realizadas pela reaÃÃo de Quellung, enquanto que a genotipagem capsular dos isolados de portadores foi realizada pela tÃcnica de multiplex PCR. De 215 crianÃas usuÃrias de creches, foram isolados S. pneumoniae em 152 (71%). As CIM de 137 isolados de portadores mostraram uma taxa resistÃncia de 71% para penicilina e de 21% para ceftriaxona. NÃo houve resistÃncia nos testes com levofloxacina. Comparado a um estudo similar, realizado hà 10 anos, em Fortaleza, nossos resultados apresentaram um aumento significativo nas taxas de resistÃncia à penicilina e ceftriaxona. De 26 isolados de nasofaringe que apresentaram resistÃncia plena, apenas, seis isolados (23%) tiveram a genotipagem capsular identificada por multiplex PCR. A incidÃncia de isolados invasivos neste estudo por ano, foi de, aproximadamente, 1 caso/100.000 hab. Dos 52 isolados, 42% apresentaram resistÃncia à penicilina e 13,5% à ceftriaxona. Os sorotipos mais comuns dos isolados sistÃmicos foram 19F (12%), 14, 3, 6A (8% cada), 4, 18C e 9V (6% cada), com cobertura estimada, tanto para vacina pneumocÃcica conjugada 7-valente quanto para a 10-valente, de 31,8%. / Streptococcus (S.) pneumoniae is considered the principal causative agent of morbidity and mortality in children younger than five years of age. All pneumococcal diseases are initiated by establishing a S. pneumoniae colonization in nasopharynx, the disease progressing to systemic disease if natural barrier are crossed. During the last decades, the increasing amount of resistant S. pneumoniae strains to beta-lactams and other classes of antimicrobials has modified the treatment of pneumococcal infection. At present, nearly 13 serotypes respond for more than 85% of invasive isolates. The 7-valent polysaccharide-conjugated pneumococcal vaccine has been widely recommended for use in children younger than five years. The aims of this study were to determine the S. pneumoniae carrier in children, the frequence of serotypes from systemic infection patients, the susceptibility profile to antimicrobials in Fortaleza, Brazil. Carrier state isolates were recovered from nasopharyngeal swabs from children attending day-care center facilities, while the isolates from systemic infection fournished by LACEN-CE. Minimal Inhibitory Concentrations (MIC) to penicillin and ceftriaxone were assessed for all isolates, and levofloxacin MIC only from nasopharyngeal isolates. MIC cut-offs were determined according to CLSI standards (2007). Serotyping of systemic isolates was performed by Quellung reaction, while capsular genotyping of carrier isolates was performed by multiplex PCR assay. OF 215 children attending day-care centers, 152 S. pneumoniae isolates were identified (71%). Penicillin MIC showed 71% of resistance, and for ceftriaxone, 21% of resistance. No resistance was found for levofloxacin MIC testing. When compared to a 10-year old similar study in Fortaleza, our results have shown a significant increase of penicillin and ceftriaxone resistance rates. Of 26 isolates tested, only six nasopharyngeal isolates (23%) were positively genotyped by multiplex PCR. The incidence of invasive isolates was 1/100,000 inhab. per year. Of 52 systemic isolates serotyped, 42% were penicillin-resistant, and 13.5% were ceftriaxone-resistant. Systemic serotypes identified were 19F, 3, 6A, 4, 18C and 9V, with a estimated coverage by the 7-valent and 10-v pneumococcal polysaccharide conjugated vaccines of 31.8%.
4

Structural diversity of the lipid A and core oligosaccharide moieties of the lipopolysaccharides from nontypeable and serotype f Haemophilus influenzae /

Yildirim, Håkan, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.
5

Recent trends in the epidemiology of gonorrhoea in Sweden : the role of importation and core groups /

Berglund, Torsten, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
6

Human salmonellosis - impact of travel and trade from a Swedish perspective /

De Jong Skierus, Birgitta, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 5 uppsatser.
7

Serotype distribution and antibiotic-resistance pattern of Streptococcus pneumoniae in Bangkok, Thailand /

Chatchai Sornchai. January 1978 (has links) (PDF)
Thesis (M.Sc. (Microbiology))--Mahidol University, 1978.
8

Development and evaluation of MALDI-TOF MS-based serotyping for Streptococcus pneumoniae / MALDI-TOF MSを用いた肺炎球菌莢膜型決定法の開発およびその性能評価

Nakano, Satoshi 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19576号 / 医博第4083号 / 新制||医||1013(附属図書館) / 32612 / 京都大学大学院医学研究科医学専攻 / (主査)教授 中川 一路, 教授 岩田 想, 教授 西渕 光昭 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
9

Caracterização fenotípica e molecular de estirpes de Haemophilus parasuis isoladas de suínos da região Centro-sul do Brasil / Phenotypic and molecular characterization of Haemophilus parasuis strains isolated from pigs in the Center- South of Brazil

Silva, Givago Faria Ribeiro da 31 March 2016 (has links)
Haemophilus parasuis é o agente etiológico da Doença de Glässer, que causa artrite, pneumonia, meningite e poliserosite em suínos e tem assumido grande importância na suinocultura moderna, uma vez que sua ocorrência tem aumentado significativamente nos últimos anos em rebanhos afetados pelo circovirus suíno tipo 2. No presente estudo foram avaliadas 117 amostras de H. parasuis isoladas dentre os anos de 2009 a 2014, isoladas de suínos de diferentes estados do da região Centro-Sul do Brasil. As estirpes foram submetidas à sorotipificação, confirmação do gênero/espécie pela PCR, o perfil de resistência a antimicrobianos foi avaliado através da determinação da concentração inibitória mínima (CIM), foi realizada a caracterização genotípica das amostras por eletroforese em gel de campo pulsado (PFGE) e por sequenciamento de múltiplos sítios (multilocus sequence typing - MLST) e a presença de genes de virulência vtaA foi analisada. Os sorotipos mais frequentes foram: 4 (21,3%), seguido do 5 (12,9%), do 13 (9,4%), do 14 (7,7%) e do sorotipo 1 (1,7%), e em alguns casos mais de um sorotipo foi identificado na mesma granja e até no mesmo animal, resultado este parecido ao encontrado no restante do mundo. Em todas as amostras o gene vtaA estava presente, para alguns antibióticos os índices de resistência foram elevados, como para tilosina (98,29%), danofloxacina (95,72%), sulfadimetoxina (88,03%), penicilina (77,7%) e a multirrestencia atingiu o índice alarmente de 93,16% das estirpes. Foram identificados 67 perfis diferentes no PFGE e das 9 amostras analisadas pelo MLST foram identificados novos STs, até então, não descritos mundialmente. Quando os novos STs foram comparados com os previamente descritos, estas se dispersaram entre as descritas em diferentes países. Neste estudo foi possível observar que as estirpes de H. parasuis brasileiras possuem alta variabilidade, tanto nos sorotipos, perfis de resistência, análises genômicas de PFGE e MLST / Haemophilus parasuis is the etiological agent of Glässer disease that causes arthritis, pneumonia, meningitis and polyserositis in pigs and has assumed great importance in modern swine production, since its occurrence has increased significantly in recent years in herds affected by porcine circovirus type 2. In the present study 117 strains of H. parasuis isolated between 2009 to 2014 were utilized, isolated from pigs of south center of Brazil. The strains were serotyping, confirmed genus/species by PCR, the antimicrobial resistance profile was evaluated determining the minimum inhibitory concentration (MIC) and strains were genotypically characterized by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and presence of vtA virulence gene. The major serotypes identified were 4 (21.3%), 5 (12.9%), 13 (9.4%), 14 (7.7%) and at last the 1 (1.7%), In some cases more than one serotype was identified in the same farm and in the same animal, this results were identified in others parts of the world. All samples had vtA gene. The resistance for some antibiotics was high for tylosin (98.29%), danofloxacin (95.72%) sulfadimetoxin (88.03%), and penicillin (77.7%). Multidrug resistance rates reached 93.16% of the samples. A total of 67 different profiles were identified in PFGE and nine samples were analyzed by MLST. All nine strains tested were identified as new STs. When these strains were compared with MLST database, they were dispersed among the strains from other countries. In this study, it was clear that the Brazilian H. parasuis strains are highly variable considering serotypes, resistance profiles, genomic analysis of PFGE and MLST
10

Caracterização fenotípica e genotípica de isolados de Actinobacillus pleuropneumoniae provenientes de diferentes estados brasileiros / Phenotypic and genotypic characterization of Actinobacillus pleuropneumoniae isolates from different Brazilian states

Costa, Bárbara Letícia Pereira 11 April 2017 (has links)
A infecção por Actinobacillus pleuropneumoniae, doença conhecida como pleuropneumonia suína, assumiu grande importância na suinocultura moderna devido à alta ocorrência observada nos rebanhos. O impacto da doença está relacionado à capacidade do agente em causar pneumonia severa, levando os animais a óbito ou doença crônica, resultando em graves prejuízos zootécnicos. Diante desse cenário, o controle e monitoramento do agente se faz importante por meio da identificação dos diferentes sorotipos, da análise genética e da determinação dos perfis de resistência aos antimicrobianos. O objetivo do presente estudo foi caracterizar fenotípica e genotípicamente estirpes de Actinobacillus pleuropneumoniae isoladas a partir de quadros de pneumonia em suínos. Um total de 85 estipes de A. pleuropneumoniae foram submetidas a reação em cadeia pela polimerase (PCR) para identificação e sorotipagem, determinação da concentração inibitória mínima de antimicrobianos, polimorfismo do comprimento de fragmentos amplificados (AFLP) e eletroforese em gel de campo pulsado (PFGE). Os sorotipos mais frequentes foram: 5 (38,8%), 10 (29,4%), 7 (5,9%), 8 (5,9%) e 6 (3,5%), sendo que 14 (16,5%) estirpes foram não tipáveis. Foi observada alta heterogeneidade de perfil genético entre as estirpes analisadas, tanto pelo AFLP quanto pelo PFGE, e o índice discriminatório para cada técnica foi 0,97 e 0,84, respectivamente. Todas as estirpes foram sensíveis ao ceftiofur, gentamicina, tulatromicina e tilmicosina, sendo que 98,8% das estirpes foram resistentes à tilosina e altas taxas de resistência foram observadas ainda para as tetraciclinas, clindamicina e sulfadimetoxina. / Infection by Actinobacillus pleuropneumoniae, a disease known as swine pleuropneumonia, has gained greater relevance to modern pig farming due to the high recurrence rate observed in herds. The impact of the disease relates to the capacity of the agent to cause severe pneumonia, leading to animal death or chronic conditions, thus resulting in severe zootechnical losses. In view thereof, the control and monitoring of the agent is key, being performed through the identification of different serotypes, genetic analysis and determination of antimicrobial resistance profiles. The objective of this study was to characterize phenotypically and genotypically Actinobacillus pleuropneumoniae strains isolated from swine with clinical presentation of pneumonia. A total of 85 strains of A. pleuropneumoniae were subject to polymerase chain reaction (PCR) for identification and serotyping, determination of the minimal inhibitory concentration, amplified fragment length polymorphism (AFLP) and pulsed field gel electrophoresis typing techniques (PFGE). Most recurring serotypes were: 5 (38.8%), 10 (29.4%), 7 (5.9%), 8 (5.9%) and 6 (3.5%), of which 14 (16.5%) strains were nontypeable. High genetic heterogeneity was observed for both AFLP and PFGE, and the discriminatory index for each technique was 0.97 and 0.84, respectively. All 85 strains were susceptible to ceftiofur, gentamicin, tulatromicin and tilmicosin, 84 of which were resistant to tylosin, and high resistance rates were also observed for clindamycin, tetracyclines and sulfadimethoxine.

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