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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.
61

A hospital outbreak of multiresistant haemophilus influenzae type B.

Sattar, Kalawathie. January 1996 (has links)
Following an outbreak of multi-resistant Haemophilus influenzae type b (Hib)infections in a tuberculosis hospital, this study was undertaken to determine carriage of Hib in 2 paediatric wards; to characterise all isolates of Hib, determine their antimicrobial susceptibility profile and the antibody response of the children to a conjugate vaccine. Prior to and one month after immunisation, oro- and nasopharyngeal swab specimens as well as venous blood were collected from each child. Isolates were tested for /3-lactamase and chloramphenicol acetyltransferase (CAT)production, their MIC's determined by the agar dilution method and characterisation of Hib isolates was performed by biotyping and analysis of outer membrane protein (OMP) profiles. An ELISA was also developed to determine serum antibody levels to polyribosyl-ribitol-phosphate (PRP), the capsular polysaccharide of Hib. The study population comprised a total of 135 children who had been hospitalised for treatment for tuberculosis. The patients were aged 4 months to 14 years with a median of 37,5 months. During the study period, none of the children developed invasive Hib disease. The overall carriage rate of Hib increased from 38% (51/135) before immunisation to 62% (84/135) after immunisation (P 0,15 /ig/ml. After immunisation, 34%(45) of patients increased their antibody levels to > 1,0 /xg/ml. There was no statistical difference between the mean antibody concentrations of patients who were colonised by Hib and those who were not (p = 0,58). The vaccine did not reduce carriage of Hib in this study population of children being treated for tuberculosis and the immune response to the vaccine was not optimal. Production of /3-lactamase and the prevalence of rifampicin resistance has implications for treatment and chemoprophylaxis in this population. OMP analysis showed a diversity of types. Multi-resistant strains causing invasive disease had the same OMP type as some multiresistant strains which colonised the children. / Thesis (M.Med.Sc.)-University of Natal, Durban, 1996.
62

Microbiology and molecular epidemiology of multiresistant haemophilus influenza type B in Durban, South Africa.

Peer, Abdool Kader Cassim. January 1988 (has links)
Microbiological and molecular epidemiological studies were conducted on 36 multi-resistant Haemophilus influenzae strains, isolated from paediatric patients, over a 26 month period (April 1986 to May 1988). The majority of strains (80,5%) had been isolated from blood and cerebrospinal fluid. More than 80% of isolates tested belonged to biotype II and 90% were of serotype B. Minimal inhibitory concentrations against 6 antibiotics (ampicillin, chloramphenicol, tetracycline, rifampicin, streptomycin and cefotaxime) confirmed the presence of multi-resistant strains. Resistance to rifampicin was confirmed in 6 (16,7%) strains. All strains were susceptible to cefotaxime. Ten transconjugants analysed with respect to their plasmid content were shown to harbour an identical 41 MDa plasmid. Restriction endonuclease digests of these plasmids with Eco R1 and Sst1 revealed almost identical restriction patterns. Outer membrane protein profiles of 19 strains revealed the predominance of one particular subtype. By combining the microbiological and molecular epidemiological findings, it is concluded that one strain of H. influenzae type b is responsible for the nosocomial acquisition of infections amongst paediatric patients. The implifications of these findings are discussed. / Thesis (M.Med.)-University of Natal, Durban, 1988.
63

Intercellular passage of epithelial cell layers a pathogenic mechanism for Haemophilus influenzae infections /

Schilfgaarde, Muriel van, January 2000 (has links)
Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.
64

Antibody responses after Hib immunisation in premature and term infants /

Dinan, Leonie Rita. January 1998 (has links) (PDF)
Thesis (M.P.H.)--University of Adelaide, Dept. of Public Health, 1999? / Includes bibliographical references (leaves 123-135).
65

Structure of an antigen-binding fragment bound to stem-loop DNA and crystallization of recombinant haemophilus influenzae e(P4) acid phosphatase

Ou, Zhonghui. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 17, 2009) Includes bibliographical references.
66

Swine influenza immunological, virological, and clinical studies of experimental infections.

Renshaw, Harland Walter, January 1970 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
67

Pneumonia bacteriana adquirida na comunidade: avaliação clínico-epidemiológica e padronização de métodos moleculares para detecção de Mycoplasma pneumoniae, Haemophilus influenzae e Streptococcus pneumoniae

Machado, Lais Del Prá Netto January 2015 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde, Programa de Pós-Graduação em Farmácia, Florianópolis, 2015. / Made available in DSpace on 2016-02-09T03:17:04Z (GMT). No. of bitstreams: 1 336847.pdf: 2261623 bytes, checksum: 5220583fc8a657b02f17b72e42ab63bc (MD5) Previous issue date: 2015 / A pneumonia pode ser causada por diversos microrganismos e classificada de forma abrangente, havendo poucos e frágeis estudos clínicos e epidemiológicos sobre pneumonias adquiridas na comunidade (PACs). Os patógenos mais frequentes nas PACs são Streptococcus pneumoniae e Haemophilus influenzae (em pneumonias típicas) e Mycoplasma pneumoniae (em pneumonias atípicas). Assim, o objetivo deste trabalho foi padronizar uma metodologia para detecção molecular dessas bactérias em amostras de orofaringe, avaliar sua prevalência e o perfil clínico-epidemiológico de pacientes com PAC em um hospital na cidade de Blumenau/SC. Para tanto, além da técnica de PCR padronizada in house, foram realizadas culturas de raspado de orofaringe e pesquisa de anticorpos específicos para detecção de M. pneumoniae. A reação de PCR realizada com os iniciadores desenhados neste estudo para M. pneumoniae apresentou sensibilidade 10x maior que a reação mais citada na literatura, e a sensibilidade das reações para S. pneumoniae e H. influenzae foi 0,1ng de DNA/reação. Dos 58 pacientes incluídos no estudo, H. influenzae e S. pneumoniae foram detectados respectivamente em 41,38% e 15,52% das amostras. M. pneumoniae não foi detectado em nenhuma amostra analisada por métodos de cultura, PCR e sorologia com anticorpos específicos IgM. Todavia não se exclui a circulação dessa bactéria na região devido à presença de anticorpos IgG específicos. A maioria dos pacientes com PAC avaliados apresentou idade =65 anos e pelo menos uma comorbidade. A maioria dos pacientes apresentou quatro ou mais sinais e sintomas, destes os mais prevalentes foram dispneia, tosse, secreção purulenta e crepitações. Evidenciou-se, neste estudo, a baixa aderência dos clínicos às Diretrizes Brasileiras para diagnóstico, estratificação e tratamento dos pacientes com suspeita de PAC, pois os exames complementares para diagnóstico e avaliação de risco dos casos e o antibiótico escolhido para grande parte dos pacientes não estava de acordo com a determinação das diretrizes. Sugere-se a replicação desta pesquisa, pois os resultados foram de encontro àqueles apresentados na literatura relacionada ao entendimento de PAC, acompanhamento dos ciclos epidêmicos de M. pneumoniae na região e conhecimento da real prevalência dos patógenos típicos, uma vez que o H. influenzae foi o patógeno mais detectado.<br> / Abstract : Pneumonia can be caused by different microorganisms and classified through comprehensive forms, but there are few and fragile clinical and epidemiological studies of community-acquired pneumonia (CAPs). The most common pathogens in CAPs are Streptococcus pneumoniae and Haemophilus influenzae (in typical pneumonia) and Mycoplasma pneumoniae (in atypical pneumonia). Therefore, the aim of this study was to standardize a methodology for molecular detection of these bacteria in the oropharynx samples, and to evaluate their prevalence and the clinical and epidemiological profile of patients with CAP in a hospital in Blumenau/SC. Thus, besides the standard technique PCR in-house, oropharyngeal swab cultures and search for specific antibodies for detection of M. pneumoniae were performed. The PCR reaction performed with primers designed in this study for M. pneumoniae showed sensitivity greater than 10-fold the most cited in the literature reaction and the sensitivity of the reactions to S. pneumoniae and H. influenzae was 0.1 ng DNA / reaction. Out of the 58 patients included in the study, H. influenzae and S. pneumoniae were detected respectively in 41.38% and 15.52% of the samples. M. pneumoniae was not detected in any sample analyzed by culture methods, PCR and serology with IgM specific antibodies. Nevertheless it is not possible to exclude the circulation of this bacterium in the region due to the presence of specific IgG antibodies. Most CAP patients evaluated were 65 years or older and had at least one comorbidity. Most of the patients had four or more signs and symptoms, the most prevalent ones were dyspnea, cough, purulent secretion and crackles. It is evident in this study the low adherence of the practitioners to Brazilian Guidelines for the diagnosis, stratification and treatment of patients with suspected CAP, as the laboratory tests for diagnosis and case risk assessment and also the antibiotic selected for most patients were not determined according to the guidelines. Replication of this research is indicated for a better understanding of the CAP, support of epidemic cycles of M. pneumoniae in the region and knowledge of the real prevalence of the typical pathogens.
68

Haemophilus influenzae e Haemophilus haemolyticus isolados de crianças que frequentam creches no município de Goiânia-GO: prevalência, fatores de risco e caracterização molecular da resistência antimicrobiana / Haemophilus influenzae and Haemophilus haemolyticus isolates from children who attend day care centers in Goiânia-GO: prevalence, risk factors and molecular characterization of antimicrobial resistance

Almeida, Robmary Matias de 26 June 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-01-11T10:54:50Z No. of bitstreams: 2 Dissertação - Robmary Matias de Almeida - 2017.pdf: 3556874 bytes, checksum: 27db72af224144cb18266e9f23af2021 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-01-11T10:55:37Z (GMT) No. of bitstreams: 2 Dissertação - Robmary Matias de Almeida - 2017.pdf: 3556874 bytes, checksum: 27db72af224144cb18266e9f23af2021 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-01-11T10:55:38Z (GMT). No. of bitstreams: 2 Dissertação - Robmary Matias de Almeida - 2017.pdf: 3556874 bytes, checksum: 27db72af224144cb18266e9f23af2021 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Haemophilus influenzae (Hi) and Haemophilus haemolyticus (Hhae) are important microorganisms present in human nasopharyngeal colonization, with rates varying according to locality, sampling frequency, individual and social factors. Hi is a pathological agent that causes diseases such as meningitis, pneumonia, sepsis and otitis media, which presents in encapsulated forms with six serotypes a, b, c, d, e, f, and uncapsulated or non-typeable (HiNT). Hhae is a nasopharyngeal comensal and rarely causes invasive diseases. The objective of this study was to estimate the prevalence of Hi and Hhae in children under five years of age attending public day care centers in the city of Goiânia-GO, to determine the circulating serotypes, to analyze the risk factors associated with the nasopharyngeal carrige, as well as to characterize the antimicrobial resistance of Hi. Were analyzed 1.188 nasopharynx swabs from healthy children between 36 and 59 months of age from October to December 2010. The samples were submitted to bacterial culture for the isolation of Haemophilus spp. For the identification of the species, the Real-Time Polymerase Chain Reaction (TR-PCR) was used. Serotyping, as well as detection of the bla TEM-1 and bla ROB-1 resistance genes, was performed through the conventional Polymerase Chain Reaction. Phenotypic detection for β-lactamase production was performed by the chromogenic cephalosporin test. The database was constructed with the statistical software SPSS (Chicago, IL, USA) version 18.0. Risk factors, children aged 3 years, low maternal schooling and three or more children under 10 years of age living in the same household of the child recruited in the study were evaluated by multivariate Poisson regression. The prevalence of Hi carriers was 54.4% (646 / 1.188), 0.9% (n = 11) of the serotype e, 0.9% (n = 11) of serotype f, 0.2% (n = 2) serotype a, 0.08% (n = 1) serotype d, 0.0% (n = 0) serotype b and c and 52.3% (621 / 1.188) of HiNT. The prevalence of Hhae was 1.2% (14 / 1.188). Among the encapsulated Hi, the prevalence of the bla TEM-1 gene was 4.0% (1/25) and the bla ROB-1 gene was 4.0% (1/25). Among the 20% (124/621) of HiNT analysed, the prevalence of the bla TEM-1 gene was 13,7% (17/124) and the prevalence of the bla TEM-1 gene was 1,6% (2/124). Continuous surveillance of Haemophilus spp. as a colonizer, is necessary to evaluate its transmission and dissemination in the population where there is a higher risk of invasive disease, to control Hib re-emergence after the vaccinacion and to continue to monitor antimicrobial resistance. / Haemophilus influenzae (Hi) e Haemophilus haemolyticus (Hhae) são importantes microrganismos presentes na colonização nasofaríngea humana, com taxas que variam de acordo com a localidade, frequência de amostragem, fatores individuais e sociais. O Hi é um agente patológico causador de doenças como meningite, pneumonia, sepse e otite média que se apresenta sob as formas capsuladas com seis sorotipos a, b, c, d, e, f, e não capsuladas ounão tipáveis (HiNT). O Hhae é comensal nasofaríngeo e raramente causa doenças invasivas. O objetivo do estudo foi estimar a prevalência de Hi e Hhae em crianças menores de cinco anos de idade que frequentam creches públicas no município de Goiânia-GO, determinar os sorotipos circulantes, analisar os fatores de risco associados ao portador nasofaríngeo, bem como caracterizar a resistência antimicrobiana dos Hi. Foram analisados 1.188 swabs de nasofaringe de crianças saudáveis entre 36 e 59 meses de idade, no período de outubro a dezembro de 2010. As amostras foram submetidas à cultura bacteriana para o isolamento do Haemophilus spp. Para identificação da espécie foi utilizada a Reação em Cadeia da Polimerase em Tempo Real (PCR-TR). A sorotipagem, assim como a detecção dos genes de resistência bla TEM-1 e bla ROB-1 , foi realizada através da Reação em Cadeia da Polimerase convencional. A detecção fenotípica para produção da β-lactamase foi executada pelo teste da cefalosporina cromogênica. A base de dados foi construída com o programa estatístico SPSS (Chicago, IL, USA) versão 18.0. Os fatores de risco, crianças com idade de 3 anos, baixa escolaridade da mãe e três ou mais crianças menores de 10 anos de idade convivendo no mesmo domicilio da criança recrutada no estudo, foram avaliados por regressão de Poisson multivariada. A prevalência de portador do Hi foi de 54,4% (646/1.188) sendo 0,9% (n=11) do sorotipo e, 0,9% (n=11) do sorotipo f, 0,2% (n=2) do sorotipo a, 0,08%(n=1) do sorotipo d, 0,0% (n=0) dos sorotipos b e c e 52,3% (621/1.188) de HiNT. A prevalência do Hhae foi de 1,2% (14/1.188). Entre os Hi encapsulados a prevalência do gene bla TEM-1 foi de 4,0% (1/25) e do gene bla ROB-1 foi de 4,0% (1/25). Em 20% (124/621) dos HiNT, a prevalência do gene bla TEM-1 foi de 13,7% (17/124) e do gene bla ROB-1 de 1,6% (2/124). A vigilância contínua do Haemophilus spp. como colonizador, se faz necessária para avaliar sua transmissão e disseminação na população onde há maior risco de incidência de doenças invasivas, controlar a re-emergência do Hib após a vacinação e continuar monitorando a resistência antimicrobiana.
69

The consequences of inhibiting chromosome polymerization in Haemophilus Influenzae d and the use of these consequences in mutant isolation

Unknown Date (has links)
"This thesis is a report on the feasibility of isolating a certain group of mutants. I call these mutants the "p.i.-related" mutants; an explanation of what they are and of my rule for grouping them together is given here. Bacterial chromosome replication consists of at least three steps: initiation, polymerization and termination/segregation (which may or may not comprise a single step). Inhibition of the polymerization step ("polymerization inhibition" or "p.i.") in a rapidly-growing bacterial population causes morphological distortion of the cells, a high death rate among them, and a number of other consequences. Recently, two great regulatory systems for bacterial cell behavior (described in Chapters IX and X) have been elucidated, and it appears that many of the consequences of p.i. might be explainable as the malfunctioning of these two systems. I define a "p.i.-related mutation" as a mutation that satisfies two criteria: First, it either causes p.i., mimics p.i., prevents p.i. or blocks the effects of p.i. Second, it exerts its effects by disrupting one of the two above-mentioned regulatory systems. The main question asked and answered in this report is: How good is each of three different methods of selection for p.i.-related mutants?"-- / Typescript. / "August, 1979." / "Submitted to the Department of Biological Science in partial fulfillment of the requirements for the degree of Master of Science." / Advisor: Johan H. Stuy, Professor Directing Thesis. / Includes bibliographical references (leaves 383-434).
70

Characterisation of plasmids conferring ampicillin resistance in South African isolates of haemophilus ducreyi

Leong, May-Yong Geraldine 27 March 1996 (has links)
A dissertation submitted to the Faculty of Medicine, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science (medicine).' Johannesburg 1996 / Fifty-two strains of Haemophilus ducreyi from various geographic regions of southern Africa (Botswana, Lesotho, Namibia, Gauteng, Natal and Transkei) isolated between 1988 to 1994 were tested for susceptibilities to five antimicrobial agents and characterized according to their plasmid content and ampicillin- resistance genes. / IT2019

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