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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.
151

Aspectos microbiologicos e epidemiologicos da infeccao por Yersinia pseudotuberculosis em bovinos no estado do Paraná - Brasil. / Epidemiological and microbiological aspects of Yersinia pseudotuberculosis infectious in bovine of Parana State - Brazil.

Jose Francisco Ghignatti Warth 03 November 1990 (has links)
A fim de pesquisar a presença de yersinia pseudotuberculosis em quadro de diarreia bovina, foram analisadas 220 amostras de fezes, 60 conteudos de intestino delgado e 56 conteudos de intestino grosso. Obteve-se isolamento positivo em 46 (21%), 9 (15%) e 5 (9%) das amostras respectivamente, totalizando 60 cepas do microrganismo. As 60 cepas de yersinia pseudotuberculosis pertenciam ao sorogrupo o iii., Apresentando identica sensibilidade aos antibioticos e quimioterapicos quando testados in vitro. Estatisticamente comprovou-se haver relação entre os isolamentos das cepas de yersinia pseudotuberculosis e os meses mais frios do ano. A cepa y. Pseudotuberculosis mostrou-se patogenica aos cobaios, quando administrada via oral. Apesar dos resultados bacteriologicos negativos, não se descartou a possibilidade do envolvimento de roedores silvestres e comensais na transmissão do microrganismo aos bovinos, podendo os proprios bovinos ou o solo, servirem como reservatorios do microrganismo. A metodologia utilizada no isolamento das cepas de y. Pseudotuberculosis possibilitou que 73,3% das mesmas fossem isoladas no cultivo primario e 26,66% apos o crioenriquecimento na temperatura de 4 GRAUS c por 7, 14 e 21 dias. / The main purposes of this research was to search for Yersinia pseudotuberculosis in faecal samples from bovine with diarrhea, from farms in the State of Paraná. We have analyzed 220 faecal samples, 60 samples from small intestine contents and 56 samples from large intestine contents. Yersinia pseudotuberculosis isolation was positive in 46 (21%), 9 (15%) and 5 (9%), respectively, totalizing 60 strains of the microrganism. The 60 strains of Yersinia pseudotuberculosis belong to serogroup 0 III, and they shown identical sensibility to antibiotics and other drugs, when tested in vitro. Through the statistical methods, X2 test, we found a positive correlation between Yersinia pseudotuberculosis isolation and the winter season. To establish the morbidity and mortality rates, cattle population was separated into three age related categories, wich are: calfs, yearlings and adults. In 1987 and 1988, the morbidity rates were 0%, 10,3% and 6,7%; 0%, 13,4% and 11,7%, respectively. In relation to mortality rates, they were 0%, 1,0% and 2,6% in 1987, and 0%, 2,1% and 2,6% in 1988. The strains of Yersinia pseudotuberculosis placed on serogroup 0 III, were pathogenic to guinea pigs, when giver per-os. We didn\'t get any isolation of Yersinia pseudotuberculosis from wild rodents and others, but we still think that may be incriminated in the transmission of the microrganism to bovines, although the bovines as well as the soil, may function as reservoires of the bacteria. Isolation of Yersinia pseudotuberculosis in primary cultures was possible in 73,33% although 26,66% of the isolations were successfull only after cold-temperature enrichment, with incubation at 4 C for 7, 14 an 21 days.
152

Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite / Phenotypic and molecular study of extended-spectrum beta-lactamases and AmpC in Enterobacteriaceae isolated from patients with suspicion of meningitis.

Andrade, Leonardo Neves de 24 April 2008 (has links)
Membros da família Enterobacteriaceae podem causar meningite associada com infecções hospitalares e/ou secundárias. A terapia empírica utilizada em pacientes com suspeita de meningite é, às vezes, ineficiente, devido à produção de beta-lactamases de espectro estendido (ESBL), que é o mecanismo mais comum de resistência às cefalosporinas de amplo espectro em enterobactérias. O objetivo deste trabalho foi estudar a produção de ESBL e AmpC por enterobactérias isoladas de líquido céfalo-raquidiano e sangue de pacientes com suspeita de meningite da região de Ribeirão Preto, no período de 2000 a 2005. O teste do disco combinado foi utilizado para a detecção fenotípica e a PCR foi utilizada para amplificar genes codificadores de ESBL e AmpC. Três (6,52 %) das 46 enterobactérias isoladas no período estudado foram produtoras de ESBL e abrigavam o gene blaCTX-M-2. As enterobactérias produtoras de ESBL foram: S. marcescens IAL 19, (isolada em Araraquara, 2002), P. mirabilis IAL 29 e E. coli IAL 45 (isoladas em Franca, respectivamente, 2003 e 2004). O gene blaCTX-M-2 foi detectado em três gêneros diferentes, sugerindo que o gene blaCTX-M é endêmicos na região de Ribeirão Preto. Os dados obtidos por este trabalho são importantes porque existem poucos relatos sobre a produção de ESBL por enterobactérias isoladas de líquido céfalo-raquidiano e sangue de pacientes com suspeita de meningite. / Members of Enterobacteriaceae family are cause of cause meningitis associated with nosocomial or secondary infection. The empiric therapy used in patients with suspicion of meningitis is, sometimes, inefficient due to extended-spectrum beta-lactamases (ESBL)- producing, that is the most common mechanism of resistance to cephalosporins in enterobacteria. The main objective of this study was to evaluate ESBL and AmpC-producing Enterobacteriaceae isolated of cerebrospinal fluid and blood from patients with suspicion of meningitis from the region of Ribeirão Preto city, during 2000 to 2005. Combination disk method was used for phenotypic detection and PCR was used to amplify genes encoding ESBL and AmpC. Three (6.52 %) out of 46 enterobacteria isolated in the period studied were detected as ESBL-producing and harbored the blaCTX-M-2 gene. The ESBL-producing enterobacteria were: S. marcescens IAL 19, (isolated in Araraquara city SP - Brazil, 2002), P. mirabilis IAL 29 e E. coli IAL 45 (isolated in Franca city SP- Brazil, respectively, 2003 e 2004). The blaCTX-M-2 gene was detected in three different genera isolated for a long time, suggesting that the blaCTX-M-2 gene is endemic in the region of Ribeirão Preto city. The data generated by this study are important because there are low reports about ESBL-producing enterobacteria isolated of cerebrospinal fluid and blood from patients with suspicion of meningitis.
153

Fatores associados à presença de microrganismos superinfectantes ou oportunistas na cavidade bucal : relações com próteses totais, condições periodontais e susceptibilidade a antimicrobianos /

Gaetti-Jardim, Ellen Cristina. January 2009 (has links)
Resumo: Este estudo avaliou a ocorrência de bactéria entérica na cavidade oral em pacientes com periodontite, pacientes com gengivite, indivíduos periodontalmente saudáveis e pacientes edentados submetidos a tratamento odontológico com reabilitação protética na Faculdade de Odontologia de Araçatuba - UNESP. Quarenta e um edentados portadores de próteses totais, 89 pacientes com gengivite, 70 pacientes com periodontite e 50 indivíduos periodontalmente saudáveis foram submetidos a exame clínico, e as condições periodontais e bucais foram registradas. Foram coletadas amostras de saliva, mucosa bucal, gengiva e biofilme supra e subgengival e bactérias foram detectados por cultura e PCR. Os microrganismos-alvo foram isolados de 75,61% dos pacientes edentados, 25,84% dos pacientes com gengivite, 30% dos pacientes com periodontite e de 18% dos indivíduos saudáveis. Por PCR, as frequências de detecção foram 87,8%, 38,2%, 64,295 e 18%, respectivamente. Significativa resistência aos antimicrobianos foi observada na maioria dos isolados, e verificou-se uma grande heterogeneidade dos marcadores resistentes à ampicilina e tetraciclina. / Abstract: This study evaluated the occurrence of enteric bacteria in oral cavity of periodontitis patients, gingivitis patients, periodontally healthy subjects and edentulous patients wearing complete denture undergoing dental treatment in Araçatuba School of Dentistry. Forty one edentulous wearing complete dentures, 89 gengivitis patients, 70 periodontitis patients and 50 periodontally realthy subjects were submitted to clinical examination, and periodontal and oral conditions were registred. Saliva, oral mucosa, subgingival and supra gingival biofilm samples were colleted and enteric bacteria were detected by culture and PCR. Targeted microorganisms were isolated from 75,61% of edentulous patients, 25,84% of gingivitis patients, 30% of periodontitis patients and from 18% of healthy individuos. By PCR, the detection frequencies were 87,8%, 38,2%, 64,29% and 18%, respectively. Significant resistance to antimicrobial agents was observed in most of isolates, and it was veriied a great heterogeneity of resistance markers to ampicillin and tetracycline. / Orientador: Ana Maria Pires Soubhia / Coorientador: Idelmo Rangel Garcia Júnior / Banca: Roberta Okamoto / Banca: Luis Fernando Landucci / Mestre
154

Escherichia coli e Salmonella sp. em suiformes nativos e exóticos assintomáticos em criações comerciais do estado de Goiás / Escherichia coli and Salmonella sp. in native and exotic asymptomatic suiformes from comercial herds in Goiás state

Faria, Adriana Marques 06 December 2016 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-01-10T16:57:36Z No. of bitstreams: 3 Tese - Adriana Marques Faria - 2016 - Parte 01.pdf: 5478875 bytes, checksum: ae9c08d62c1ad44305030954fe0b0a5e (MD5) Tese - Adriana Marques Faria - 2016 - Parte 02.pdf: 16834328 bytes, checksum: 2faf307ee33c6a223a00b491091a66f2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-11T09:54:12Z (GMT) No. of bitstreams: 3 Tese - Adriana Marques Faria - 2016 - Parte 01.pdf: 5478875 bytes, checksum: ae9c08d62c1ad44305030954fe0b0a5e (MD5) Tese - Adriana Marques Faria - 2016 - Parte 02.pdf: 16834328 bytes, checksum: 2faf307ee33c6a223a00b491091a66f2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-01-11T09:54:12Z (GMT). No. of bitstreams: 3 Tese - Adriana Marques Faria - 2016 - Parte 01.pdf: 5478875 bytes, checksum: ae9c08d62c1ad44305030954fe0b0a5e (MD5) Tese - Adriana Marques Faria - 2016 - Parte 02.pdf: 16834328 bytes, checksum: 2faf307ee33c6a223a00b491091a66f2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-12-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The closeness beteween wild and domestic animals with humans may result in common diseases involving these three groups, including zoonotic and antropozoonotic diseases. The study of bacteria and disease that affects animals is an important way to approach epidemiologic control and sanitary vigilance, as we do not understand the roll of wild animals in transmitting diseases among wild, exotic and domestic animals. The main objective of the present study was to search the presence of Escherichia coli and Salmonella sp. from rectal swabs of non-domesticated Suiformes in Commercial herds in Goiás State. It was collected rectal swabs of 100 Sus scrofa scrofa, 60 T. pecari and 30 P. tajacu, from different ages. The samples were used in order to obtain the isolation, antimicrobial profile, hemolisin test for E. coli and virulence and resistance gene presences in both bacteria. The serotyping was performed with polyvalent anti-O serum and the virulence and resistance gene deteccion by PCR technique. The results shown high rates of antimicrobial resistance and virulence and resistance genes in analyzed groups of E. coli. The isolation of Salmonella sp. occurred in one sample of S. scrofa, with high rates of antimicrobial resistance also, but no resistance and virulence genes were detected in this isolate. We must pay attention to the possibility of horizontal gene transference of virulence factors and resistance trough contaminated water and food, that may transform commensal bacteria in possible pathogenic agents. It is conclude: that Salmonella sp. is not commonly isolated from T. pecari and P. tajacu, showing low frequency of isolation in S. scrofa in these conditions; and E. coli with multidrug resistance patterns is isolated from S. scrofa, T. pecari and P. tajacu in commercial herds from Goiás State. / A proximidade de animais silvestres com animais domésticos e seres humanos pode resultar no aparecimento de doenças comuns a estes três grupos, incluindo doenças zoonóticas. O estudo de bactérias e doenças que acometem animais silvestres é importante para atuar na forma de controle epidemiológico e vigilância sanitária, visto que não se compreende o papel destes animais na transmissão de doenças entre outros animais silvestres, exóticos e domésticos. O presente estudo foi desenvolvido com o objetivo de pesquisara presença das bactérias Escherichia coli e Salmonella sp. em suabes retais provenientes de Suiformes não domesticados em criações comerciais no Estado de Goiás. Foram colhidos suabes retais de 100 Sus scrofa scrofa, 60 de Tayassu pecari e 30 de Pecari tajacu, de diferentes faixas etárias. À partir do material colhido fez-se o isolamento, perfil antimicrobiano, teste de hemólise para E. coli e detecção de genes de virulência e de resistência das bactérias. Para a detecção dos agentes, foi realizado exame bacteriológico convencional e ensaios de suscetibilidade a antimicrobianos. Foi realizadas a tipificação sorológica por teste sorológico com soro polivalente anti-O para a bactéria Salmonella e detecção de genes virulência e de resistência pela técnica de PCR nos isolados. Os resultados obtidos demonstraram altas taxas de resistência aos antimicrobianos e presença de genes de virulência em amostras de E. coli em todos os grupos testados. O isolamento de Salmonella sp. foi possível em uma amostra de S. scrofa, que apresentou também altas taxas de resistência à antimicrobianos, mas não houve detecção de genes de virulência ou de resistência neste isolado. Conclui-se que: nesta condição de criação Salmonella sp. não é isolada comumente de T. pecari e P. tajacu, sendo isolada em baixa frequência de S. scrofa; e que E. coli é isolada de S. scrofa, T. pecari e P. tajacu em rebanhos comerciais do Estado de Goiás, com múltiplos padrões de resistência antimicrobiana.
155

Avaliação das condições microbiológicas da água e de peixes do Rio Mearim, no município de Bacabal-MA / Evaluation of the microbiological conditions of the water and fish of the Mearim River, in Bacabal-MA

Paiva, Thaís Vieira 27 July 2016 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-12T17:09:21Z No. of bitstreams: 1 ThaisPaiva.pdf: 594078 bytes, checksum: dab90ce2d1146580c6639f13c540e873 (MD5) / Made available in DSpace on 2017-06-12T17:09:21Z (GMT). No. of bitstreams: 1 ThaisPaiva.pdf: 594078 bytes, checksum: dab90ce2d1146580c6639f13c540e873 (MD5) Previous issue date: 2016-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Contaminated waters not only directly affect human health but also cause serious damage to the aquatic biota, causing deterioration in fish quality. The objective was to evaluate the hygienic-sanitary conditions of the water and the fresh fish from the Mearim river in BacabalMa during the rainy season, through the identification of the potentially pathogenic bacteria. A total of 54 samples of water and 54 samples of fresh fish that were colected between October 2015 and March 2016, which were submitted to the quantification of total and thermo tolerant coliformes by the thechnique of Most Probable Number (MPN/g) and Clostridium sulphite reducing research. After that, the biochemical identification of isolated bacteria coming from the Enterobacteriaceae family was performed using commercial biochemical tests. The results showed that the microbiological quality of the water and the fish is unsatisfactory due to the high contamination rates of thermotolerant coliforms, being below the microbiological quality standards, as well as the the presence of total coliforms and Clostridium sulphite reducers in considerable concentrations both in water and in fish. The water’s contamination by coliforms was significantly higher than in the fishes, in the dry season as well as in the rainy season. Escherichia coli was the bacterium with the highest frequency of isolation in water samples, both in the dry season and in the rainy season. Citrobacter diversus and Serratia odorífera also had important isolation frequency in the water samples of the two seasons. In the fish samples, the highest frequency of identification was also from Escherichia coli. Serratia odorífera and Citrobacter diversus also had relevant frequencies in the dry season. In the rainy season Escherichia coli kept the highest frequency of isolation, followed by Serratia odorífera and Citrobacter freundii. / Águas contaminadas não só afetam diretamente a saúde humana como também causam sérios danos à biota aquática, provocado deterioração na qualidade dos peixes. Objetivou-se avaliar as condições higiênico-sanitárias da água e dos peixes frescos oriundos do rio Mearim, Bacabal/MA, no período seco e chuvoso, através da identificação de bactérias potencialmente patogênicas. Foram analisadas 54 amostras de água e 54 amostras de peixes frescos coletadas no período de outubro de 2015 a março de 2016, as quais foram submetidas à quantificação de coliformes totais e termotolerantes pela técnica do Número Mais Provável (NMP/g) e pesquisa de Clostridium sulfito redutor. Em seguida a identificação bioquímica das bactérias isoladas da família Enterobacteriaceae foi realizada utilizando testes bioquímicos comerciais. Os resultados mostraram que a qualidade microbiológica da água e dos peixes estava insatisfatória, devido aos elevados índices de contaminação por coliformes termotolerantes, estando fora dos padrões de qualidade microbiológica exigidos pelas legislações vigentes, e pela presença de coliformes totais e Clostridium sulfito redutores. A contaminação da água por coliformes foi significativamente maior que nos peixes, tanto no período seco quanto no chuvoso. Escherichia coli foi a bactéria com maior frequência de isolamento nas amostras de água, tanto no período seco quanto no chuvoso. Citrobacter diversus e Serratia odorífera também tiveram importante frequência de isolamento nas amostras de água dos dois períodos. Nas amostras de peixes a maior frequência de identificação também foi de Escherichia coli. Serratia odorífera e Citrobacter diversus também tiveram frequências relevantes no período seco. No período chuvoso Escherichia coli manteve-se com maior frequência de isolamento, seguida de Serratia odorífera e Citrobacter freundii.
156

CARBAPENEM-RESISTANT <em>ENTEROBACTERIACEAE</em>: EPIDEMIOLOGY, GENETICS, <em>IN VITRO</em> ACTIVITY, AND PHARMACODYNAMIC MODELING

Kulengowski, Brandon 01 January 2019 (has links)
Background: Infections caused by carbapenem-resistant Enterobacteriaceae (CRE) such as Escherichia coli and Klebsiella pneumoniae are among the most urgent threats of the infectious disease realm. The incidence of these infections has been increasing over the years and due to very limited treatment options, mortality is estimated at about 50%. By 2050, mortality from antimicrobial resistant infections is expected to surpass cancer at 10 million deaths annually. Methods: We evaluated 18 contemporary antimicrobials against 122 carbapenem-resistant Enterobacteriaceae using a variety of antimicrobial susceptibility testing methods according to Clinical Laboratory Standards Institute guidelines. Time-kill studies were performed on clinical isolates with variable resistance to meropenem, amikacin, and polymyxin B. Phenotypic expression assays were performed on all isolates and whole genome sequencing was performed on 8 isolates to characterize molecular resistance mechanisms. Pharmacodynamic modeling of meropenem and polymyxin B was also conducted. Results: CRE were primarily K. pneumoniae, and Enterobacter spp. 60% expressed Klebsiella pneumoniae carbapenemase (KPC) only, 16% expressed Verona Integron-encoded Metallo-beta-lactamase (VIM) only, 5% expressed KPC and VIM, and 20% expressed other mechanisms of resistance. Antimicrobial susceptibility testing indicated the most active antimicrobials against CRE were ceftazidime/avibactam, imipenem/relebactam, amikacin, tigecycline, and the polymyxins. Etest® strips did not reliably measure polymyxin B resistance. The automated testing system, BD Phoenix™, consistently reported lower MICs than the gold standard broth microdilution. Time-kill studies showed regrowth at clinically achievable concentrations of meropenem alone (4, 16, and 64 mg/L), polymyxin B alone (0.25 and 1 mg/L), or amikacin alone (8 and 16 mg/L), but combinations of meropenem with either polymyxin B or amikacin were bactericidal and synergistic. Meropenem administered simultaneously or prior to polymyxin B exhibited superior activity to polymyxin B administered first. Conclusions: Novel carbapenemase-inhibitor combinations (ceftazidime/avibactam and imipenem/relebactam) exhibit the best activity against KPC-producing CRE. The polymyxins, amikacin, and tigecycline exhibit the best activity against VIM-producing CRE. Meropenem in combination with polymyxin B is bactericidal and synergistic when the meropenem MIC is ≤32 mg/L, and meropenem should never be administered after polymyxin B. Meropenem and amikacin is bactericidal and synergistic when the amikacin MIC is ≤16 mg/L. Etest® strips should not be used for characterizing polymyxin B or colistin activity. Clinicians should be aware that automated testing systems may produce biased susceptibility results relative to the gold standard method, broth microdilution, which may influence interpretation of in vitro results.
157

Mechanism of tumour resistance in salmonella-immunized mice

La Posta, Vincent J. (Vincent James) January 1983 (has links) (PDF)
Bibliography: leaves 218-251.
158

Transfert d'un gène de résistance aux beta-lactamines blaCTX-M-9 entre Salmonella et les entérobactéries de la flore intestinale humaine : influence d'un traitement antibiotique

Faure, Stéphanie 14 May 2009 (has links) (PDF)
La dissémination mondiale de la résistance aux β-lactamines est un problème de santé publique majeur. Les voies de transmission de la résistance sont mal connues, néanmoins de nombreux arguments attestent du potentiel transfert de bactéries résistantes et de gènes de résistance entre l'animal et l'homme. L'objectif du présent travail est d'évaluer le transfert du gène de résistance blaCTX-M-9 entre une souche d'origine animale, Salmonella enterica Virchow et les entérobactéries de la flore humaine, et l'impact d'un traitement à une β- lactamine sur ce transfert. Dans un modèle de rat associé à une flore humaine, le transfert du gène de résistance n'est pas détectable entre S. enterica Virchow et les entérobactéries de la flore. Pourtant l'inoculation concomitante d'une souche d'Escherichia coli suffit à observer la diffusion du gène de résistance. La pression de sélection ne permet pas d'augmenter le transfert de gène mais contribue largement à la sélection et à la colonisation de salmonelles résistantes dans le tractus digestif. L'analyse des paramètres pharmacocinétiques et pharmacodynamiques confirme également la pertinence des critères de substitution dans la prédiction de l'efficacité d'un traitement au céfixime en présence de telles souches. L'une des stratégies thérapeutiques proposée consiste à utiliser une combinaison de β-lactamines et d'inhibiteurs de β-lactamases.
159

Antimicrobial Resistance and Production of Extended Spectrum Beta-Lactamases in Enterobacteriaceae from Birds in Bangladesh

Hasan, Badrul January 2013 (has links)
The dissemination of members of the Enterobacteriaceae family with extended spectrum beta-lactamases (ESBLs) and metallo-beta-lactamases (MBLs) has become a global concern. ESBLs and MBLs have been reported in humans, domestic animals, wildlife and the environment, and their isolation frequencies are increasing rapidly worldwide.  Most studies have been performed in developed countries and quite few in developing countries, where the antibiotic consumption is often poorly controlled. To explore the environmental contamination of antibiotic resistance in Bangladesh, and of ESBLs and MBLs in particular, fecal samples from poultry and wild birds were studied in this thesis. Samples were collected from both sick birds (poultry having Escherichia coli infections) and healthy birds (free-range poultry, seagulls and crows) residing in different environmental niches. Samples from patients and fresh/sea water were included, to follow the chain of antibiotic resistance in bacteria from humans to the environment. Information regarding the antibiotic usage in poultry production was also collected. The susceptibility of avian E. coli isolates cultured with and without selective pressure was tested against antibiotics commonly used in human and veterinary medicine in Bangladesh. Special attention was paid to ESBL-producing isolates, which were further characterized genetically. The results of the studies showed that E. coli isolates from commercial poultry, free-range poultry, gulls and crows were resistant to several classes of antibiotics, and that the level and spectrum of antibiotic resistance varied between different bird populations. There was no NDM-producer found among the birds, but ESBL-producing Enterobacteriaceae could be found in up to 59% of the crows, the birds with the highest carriage rate of multiresistant  Enterobacteriaceae of all bird species studied. The most common ESBL-type was CTX-M-15, which also is the most common in the human population in Bangladesh. Birds also shared clinically important sequence types with humans, including E. coli clone O25b-ST131. In conclusion, ESBL-producing bacteria with multiresistance are easily spread to wild birds. Their opportunistic feeding behavior at poorly managed hospital waste dumps and nearby water bodies makes them into both reservoirs and active spreaders. The high level of antibiotic resistant and ESBL-producing bacteria in the bird population of Bangladesh is worrying, and there is no easy solution in sight. Nationwide programs are necessary to both improve the management of hospital waste and sewage and the control of the antibiotic usage to prevent further environmental contamination. / <p>Time of defence has been changed to 09:00 am on 2013-05-27</p>
160

The prevalence of coliform species in selected food products with special reference to the detection of Citrobacter koseri.

Ramashia, Shonisani Eugenia. January 2013 (has links)
M. Tech. Food Technology. / Problems to be solved in this project was to validate isolation and detection methods for C. koseri; to assess the environmental prevalence of C. koseri by testing a range of raw South African food products and to determine the specific risk of neonatal infections by monitoring powdered infant formula on the South African market for the presence of this organism.

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