subject:(Beta lactamases)

Laurentian University

1. Rotondo, Caitlyn Michelle. The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides .

Degree: 2014, Laurentian University

URL: https://zone.biblio.laurentian.ca/dspace/handle/10219/2291

► Metallo-β-lactamases (MBLs) are major contributors to bacterial antibiotic resistance due to their ability to cleave most β-lactam antibiotics. At the present time there are no… (more)

Subjects/Keywords: Bacteria; Antibiotic Resistance; β-Lactamases; Bacteria, AntMetallo-β-lactamases

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APA (6^th Edition):

Rotondo, C. M. (2014). The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides . (Thesis). Laurentian University. Retrieved from https://zone.biblio.laurentian.ca/dspace/handle/10219/2291

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rotondo, Caitlyn Michelle. “The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides .” 2014. Thesis, Laurentian University. Accessed March 07, 2021. https://zone.biblio.laurentian.ca/dspace/handle/10219/2291.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rotondo, Caitlyn Michelle. “The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides .” 2014. Web. 07 Mar 2021.

Vancouver:

Rotondo CM. The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides . [Internet] [Thesis]. Laurentian University; 2014. [cited 2021 Mar 07]. Available from: https://zone.biblio.laurentian.ca/dspace/handle/10219/2291.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rotondo CM. The inhibition of the VIM-2 and IMP-1 METALLO-β-LACTAMASES by cationic peptides . [Thesis]. Laurentian University; 2014. Available from: https://zone.biblio.laurentian.ca/dspace/handle/10219/2291

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Black, Jennifer A. Detection of Plasmid-Mediated AmpC b-Lactamases.

Degree: M.S. in Medical Microbiology and Immunology, Medical Microbiology and Immunology (graduate program), 2004, Creighton University

URL: http://hdl.handle.net/10504/68463

► Although plasmid-mediated AmpC b-lactamases were first reported in the late 1980's, most clinical laboratories and physicians remain unaware of their clinical importance. Current detection methods… (more)

▼ Although plasmid-mediated AmpC b-lactamases were first reported in the late 1980's, most clinical laboratories and physicians remain unaware of their clinical importance. Current detection methods for organisms producing plasmid-mediated AmpC b-lactamases are time-consuming and technically-demanding for clinical laboratories to perform on a routine basis. Multiplex PCR is also available as a research tool for the detection of this resistance mechanism but is not yet available for routine use. Because of the lack of PCR and the difficulty of current detection methods, organisms producing these types of b-lactamases often go undetected and have therefore been responsible for nosocomial and community outbreaks. The detection of organisms producing these b-lactamases is thus important for infection control and to ensure effective therapeutic options. Currently, there are no recommendations available from the National Committee for Clinical Laboratory Standards (NCCLS) for detection of organisms producing plasmid-mediated AmpC b-lactamases. Therefore, clinical laboratories need an inexpensive and convenient method to detect this resistance mechanism.|Because of this need, two new methods for detection of plasmid-mediated AmpC b-lactamases were developed and investigated in this research. The first method was based on a reagent disk test that utilizes a filter paper disk impregnated with a permeabilizing agent to detect plasmid-mediated AmpC b-lactamases. The second method was based on the diagnostic utility of the AmpC b-lactamase inhibitors 48-1220 (Ro 48-1220) and LN-2-128 for detection of organisms producing plasmid-mediated AmpC b-lactamases using methodology similar to the NCCLS guidelines for ESBL confirmation disk test. In this research, the reagent disk test method proved to be a very sensitive, specific, and convenient method for detection of plasmid-mediated AmpC b- lactamases in organisms lacking a chromosomal AmpC b-lactamase. The AmpC b- lactamase inhibitor disk test method also proved to be simple to perform and easy to interpret having clear-cut guidelines for interpretation. Both methods developed in this research showed potential and should be further investigated. Advisors/Committee Members: Thomson, Kenneth S. (advisor), Black, Jennifer A. (cuauthor).

Subjects/Keywords: beta-Lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Black, J. A. (2004). Detection of Plasmid-Mediated AmpC b-Lactamases. (Masters Thesis). Creighton University. Retrieved from http://hdl.handle.net/10504/68463

Chicago Manual of Style (16^th Edition):

Black, Jennifer A. “Detection of Plasmid-Mediated AmpC b-Lactamases.” 2004. Masters Thesis, Creighton University. Accessed March 07, 2021. http://hdl.handle.net/10504/68463.

MLA Handbook (7^th Edition):

Black, Jennifer A. “Detection of Plasmid-Mediated AmpC b-Lactamases.” 2004. Web. 07 Mar 2021.

Vancouver:

Black JA. Detection of Plasmid-Mediated AmpC b-Lactamases. [Internet] [Masters thesis]. Creighton University; 2004. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10504/68463.

Council of Science Editors:

Black JA. Detection of Plasmid-Mediated AmpC b-Lactamases. [Masters Thesis]. Creighton University; 2004. Available from: http://hdl.handle.net/10504/68463

University of Hong Kong

3. Liu, Chunjiao. Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals.

Degree: 2014, University of Hong Kong

URL: http://hdl.handle.net/10722/206582

► A novel and effective mechanism of forming resistance to beta-lactam antibiotics by producing hybrid CTX-M-type beta-lactamases through genetic recombination was reported recently, albeit sporadically. Its… (more)

▼ A novel and effective mechanism of forming resistance to beta-lactam antibiotics by producing hybrid CTX-M-type beta-lactamases through genetic recombination was reported recently, albeit sporadically. Its primary introductory factor is the horizontal resistant gene transfer that occurs within the 876 bp 〖bla〗_(CTX-M) gene in Escherichia coli isolates, followed by the extensive application of beta-lactam antimicrobials. 〖bla〗_(CTX-M) originated from the nonpathogenic commensal Kluyvera spp., but it has become widely distributed in pathogenic organisms by plasmid-mediated gene transfer. Beta-lactams are effective against both gram-positive and gram-negative bacteria. However, misusing or overusing of beta-lactams has caused a globally corresponding emergence of antimicrobial resistant strains because of the selective pressure. This study included a total of 1,441 E. coli isolates, including 1,101 from six categories of animals and 340 from humans of both sexes. In total 612 strains were detected as extended spectrum beta-lactamase (ESBL)-positive. By using molecular tests on 248 ESBL-producers, 14 non-duplicate strains harbouring hybrid CTX-M-type beta-lactamases were found in a subset of 170 animal strains. A total of three alleles for hybrid CTX-M-type beta-lactamases (n = 14) were found, namely, CTX-M-64 (n = 6), CTX-M-123 (n = 6), and CTX-M-132 (n = 2). Six 〖bla〗_(CTX-M-64) and one 〖bla〗_(CTX-M-132) genes were located on approximately 70 kb IncI2 plasmids, and five 〖bla 〗_(CTX-M-123) genes were carried by 110 kb IncI1 (plasmid ST108) plasmids. All the 〖bla〗_(hybrid CTX-M) genes were placed between ISEcp1 followed by a 45 bp spacer and a 47 bp spacer followed by a 344 bp orf477delta gene. Among the six CTX-M-64-harbouring isolates detected, three of them were ST1011, phylogroup E, from chickens; the remaining three were ST224, phylogroup B1; ST93 CC168, phylogroup A; and ST117, phylogroup F. Every CTX-M-64-harbouring isolate had the co-resistance trait against both ciprofloxacin and tetracycline. The CTX-M-123-harbouring isolates were ST1485, phylogroup E; ST2732, phylogroup D; ST10, phylogroup A; ST457, phylogroup F; and ST 1196, phylogroup B1. All six CTX-M-123-harbouring strains were co-resistant to trimethoprim-sulphamethoxazole and tetracycline, and all of their transconjugants or transformants inherited the ability to resist fosfomycin. Both CTX-M-132-harbouring strains came from phylogroup A. One strain was ST3103, and the other one with a non-transferable plasmid was ST746. This study unravels the molecular epidemiology of hybrid CTX-M-type beta-lactamase-harbouring E. coli isolates. It also compared the prevalence of these isolates among both animal and human strains. Although hybrid CTX-Mtype beta-lactamases were not found in 340 clinical urinary isolates, 14 hybrid CTX-M-type beta-lactamases were identified in 14 animals in just one year. Hence, this study sets off alarm bells for the public to become more concerned about the antimicrobial resistance situation among animals. Furthermore, the…

Subjects/Keywords: Beta lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liu, C. (2014). Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/206582

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Chunjiao. “Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals.” 2014. Thesis, University of Hong Kong. Accessed March 07, 2021. http://hdl.handle.net/10722/206582.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Chunjiao. “Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals.” 2014. Web. 07 Mar 2021.

Vancouver:

Liu C. Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals. [Internet] [Thesis]. University of Hong Kong; 2014. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10722/206582.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu C. Molecular epidemiology of hybrid CTX-M type beta-lactamases among Escherichia coli isolates from human and animals. [Thesis]. University of Hong Kong; 2014. Available from: http://hdl.handle.net/10722/206582

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong

4. Hui, Ka-long, Aaron. Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism.

Degree: 2014, University of Hong Kong

URL: http://hdl.handle.net/10722/206564

► Introduction: The New Delhi metallo-β-lactamase (NDM-1) is an enzyme synthesized by bacterium which hydrolyses β-lactam antibiotics and inhibits their antibiotic effects. Its active site is… (more)

▼ Introduction: The New Delhi metallo-β-lactamase (NDM-1) is an enzyme synthesized by bacterium which hydrolyses β-lactam antibiotics and inhibits their antibiotic effects. Its active site is highly diverse and the hydrolysis mechanism is not yet fully understood. So, there is currently no clinically useful inhibitor for this enzyme. Due to this β-lactam resistant characteristics and the ease of horizontal gene transfer between bacteria, NDM-1 producing bacteria poses a great threat to public health. Objective: Structural analysis on Zn-Zn distance in the active site of NDM-1 was carried out in order to gain a better insight on its hydrolysis mechanism. Method: Structures of NDM-1 were obtained from PDB database and were viewed on PyMOL. Out of 22 NDM-1 structures searched, 12 of them fulfilled the inclusion criterion and were included in this study. Zn-Zn distances were compared with different factors including pH and temperature during crystallization, presence of water in the active site and nature of ligand bound to active site. Results: A trend was observed when Zn-Zn distances were compared with pH. There was also a correlation between Zn-Zn distance and nature of ligand. Distance between the 2 zinc ions in the active site increased in acidic pH value of 6.5 or below and it favours substrate hydrolysis while neutral or alkaline pH shortened the distance between zinc ions leading to hydrolysis inhibition. Discussion: One NDM-1 structure can hydrolyse the substrate in the absence of water molecule. It suggested that there might be another alternative mechanism which does not involve water molecule as nucleophile. Future study can be carried out to verify this hypothesis. On the other hand, it was also suggested that a lower pH, likely to be a pH value of 6.5 or below, could lead to a relatively higher Zn-Zn distance, likely to be 4.00 Å or above. A Zn-Zn distance of 4.00 Å or above would facilitate the hydrolysis mechanism. In other words, a pH value lower than 6.5 might also promote the hydrolysis action against β-lactams. These give us a deeper understanding into the hydrolysis mechanism of NDM-1 and might be useful in future development of clinical inhibitor to tackle the public health threat brought by NDM-1.

Subjects/Keywords: Beta lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hui, Ka-long, A. (2014). Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/206564

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hui, Ka-long, Aaron. “Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism.” 2014. Thesis, University of Hong Kong. Accessed March 07, 2021. http://hdl.handle.net/10722/206564.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hui, Ka-long, Aaron. “Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism.” 2014. Web. 07 Mar 2021.

Vancouver:

Hui, Ka-long A. Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism. [Internet] [Thesis]. University of Hong Kong; 2014. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10722/206564.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hui, Ka-long A. Structural analysis of Zn-Zn distance in NDM-1's beta-lactam hydrolysis mechanism. [Thesis]. University of Hong Kong; 2014. Available from: http://hdl.handle.net/10722/206564

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. VERAS, Dyana Leal. Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m .

Degree: 2014, Universidade Federal de Pernambuco

URL: http://repositorio.ufpe.br/handle/123456789/12070

► O objetivo deste trabalho foi determinar a ação in vitro de antibióticos β-lactâmicos em isolados de Klebsiella pneumoniae portadores dos genes blaKPC, blaSHV, blaTEM ou… (more)

▼ O objetivo deste trabalho foi determinar a ação in vitro de antibióticos β-lactâmicos em isolados de Klebsiella pneumoniae portadores dos genes blaKPC, blaSHV, blaTEM ou blaCTX-M, desenvolvendo embasamento teórico para futura proposição de novas combinações terapêuticas. Sete isolados de K. pneumoniae foram utilizados, sendo 3 clínicos, 2 de comunidade e 2 de microbiota. Os isolados clínicos e de comunidade são portadores de genes codificantes de ESBL ou KPC e os de microbiota de -lactamases clássicas. Os genes de resistência foram identificados por PCR e seqüenciados utilizando primers específicos. A primeira fase deste estudo identificou os efeitos ultra-estruturais causados por -lactâmicos in vitro nos isolados clínicos e de microbiota de K. pneumoniae. Os isolados clínicos foram submetidos a concentrações clinicamente relevantes de ceftazidima, cefotaxima, aztreonam e/ou imipenem e os isolados de microbiota a ampicilina e amoxicilina, para análise pela Microscopia Eletrônica de Transmissão (MET) e Varredura (MEV). Diferentes alterações morfológicas e ultra-estruturais foram identificadas, como filamentação celular, perda de material citoplasmático e deformação dos septos de divisão, após submissão aos antibióticos, tanto nos isolados clínicos de K. pneumoniae como nos obtidos de microbiota. A segunda fase deste estudo determinou a influência destes antibióticos na produção de cápsula polissacarídica (CPS) nos isolados clínicos e de comunidade de K. pneumoniae. Os isolados foram submetidos a concentrações clinicamente relevantes de cefotaxima, ceftazidima, aztreonam e/ou imipenem para analise pela MET, utilizando citoquímica de carboidratos. Todos os isolados tiveram confirmação da presença da região promotora do operon envolvido na produção de CPS, identificado através de PCR e sequenciamento. A ceftazidima e o aztreonam foram capazes de inibir a produção de CPS nos isolados de K. pneumoniae produtores de ESBLs mas não no isolado produtor de KPC, o qual teve sua síntese fortemente inibida apenas pelo imipenem. A cefotaxima não interferiu na produção de CPS em nenhum dos isolados analisados. Nossos resultados demonstraram que antibióticos -lactâmicos possuem ação residual in vitro nos isolados analisados, sugerindo que a produção de ESBL e KPC por isolados de K. pneumoniae não são capazes de evitar completamente a interação de antibióticos β-lactâmicos com as PBPs bacterianas. Podemos concluir ainda que a ceftazidima, o aztreonam e o imipenem, podem ser capazes de inibir a produção de CPS em isolados clínicos e de comunidade de K. pneumoniae, contribuindo para diminuir a expressão do fator de virulência mais importante desta espécie bacteriana. Advisors/Committee Members: SANTOS, Fábio André Brayner dos (advisor), ALVES, Luiz Carlos (advisor).

Subjects/Keywords: Klebsiella pneumoniae; Beta-lactâmicos; Beta-lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

VERAS, D. L. (2014). Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m . (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/12070

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

VERAS, Dyana Leal. “Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m .” 2014. Thesis, Universidade Federal de Pernambuco. Accessed March 07, 2021. http://repositorio.ufpe.br/handle/123456789/12070.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

VERAS, Dyana Leal. “Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m .” 2014. Web. 07 Mar 2021.

Vancouver:

VERAS DL. Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m . [Internet] [Thesis]. Universidade Federal de Pernambuco; 2014. [cited 2021 Mar 07]. Available from: http://repositorio.ufpe.br/handle/123456789/12070.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

VERAS DL. Determinação da ação in vitro de antibióticos β-lactâmicos frente isolados multidroga-resistentes de Klebsiella pneumoniae portadores dos genes blakpc, blashv, blatem e blactx-m . [Thesis]. Universidade Federal de Pernambuco; 2014. Available from: http://repositorio.ufpe.br/handle/123456789/12070

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

6. Arruda, Eduardo Guimarães Ratier de, 1990-. Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III.

Degree: 2019, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/334507

► Abstract: A systematic study of the first coordination sphere over the reactivity and structure of metallo-beta-lactamase (MBL) monozinc model complexes is reported. Three ZnII complexes… (more)

▼ Abstract: A systematic study of the first coordination sphere over the reactivity and structure of metallo-beta-lactamase (MBL) monozinc model complexes is reported. Three ZnII complexes with the tripodal ligands forming the series [Zn(N-NNN)], [Zn(N-NNS)], and [Zn(N-NNO)] where N-NNX represents the tripodal donor atoms, were investigated regarding their ability to mimic MBL. The tripodal series was inspired by MBL active sites in the respective subclasses, which represents the (His, His, His) Zn1 site present in B1 and B3 subclasses, (His, His, Asp) presented in B3 subclass site and the thiolate presented in B1 and B2 sites. The results were reinforced by DFT and TD-DFT calculations. XAS analysis demonstrated the ZnII electronic deficiency significantly changes in the order [Zn(N-NNS)] < [Zn(N-NNN)] < [Zn(N-NNO)]. This effect directly affects the reactivity over nitrocefin and amoxicillin, observed by the kinetics of hydrolysis, which follows the same trend as the other measurements. NMR spectroscopy revealed that the polarization of carboxylic group in the substrate changes accordingly affecting the hydrolysis kinetic. Our results also demonstrated that not only Lewis acidity is changed by the ligand system but also the softness character of the metal. [Zn(N-NNS)] in particular, is softened by the thiolate, promoting the ligand substitution reaction with solvents and favoring secondary interaction with substrates, not observed for [Zn(N-NNO)]. XRD of the models reveals their similar geometric aspects in comparison to the single-crystal structure of GOB-18 (5K0W) MBL. The interaction of these model complexes with AuI/III complexes was evaluated using 1H NMR and ESI-MS and showed a selective interaction depending on the first coordination sphere and in agreement with Pearson acid-base behavior. The present work demonstrate the ZnII electronic details must be considered in the design of new MBL models and can be used in further aid in the design of new clinically useful MBL inhibitors Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Abbehausen, Camilla, 1979- (advisor), Universidade Estadual de Campinas. Instituto de Química (institution), Programa de Pós-Graduação em Química (nameofprogram), Buffon, Regina (committee member), Corbi, Pedro Paulo (committee member), Ferreira, Ana Maria da Costa (committee member), Bergamini, Fernando Rodrigues Goulart (committee member).

Subjects/Keywords: Química bioinorgânica; Metaloproteínas; Beta-Lactamases; Bioinorganic chemistry; Metalloproteins; Beta-Lactamases

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APA (6^th Edition):

Arruda, Eduardo Guimarães Ratier de, 1. (2019). Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/334507

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Arruda, Eduardo Guimarães Ratier de, 1990-. “Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III.” 2019. Thesis, Universidade Estadual de Campinas. Accessed March 07, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/334507.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Arruda, Eduardo Guimarães Ratier de, 1990-. “Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III.” 2019. Web. 07 Mar 2021.

Vancouver:

Arruda, Eduardo Guimarães Ratier de 1. Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III. [Internet] [Thesis]. Universidade Estadual de Campinas; 2019. [cited 2021 Mar 07]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/334507.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Arruda, Eduardo Guimarães Ratier de 1. Miméticos de metalo-beta-lactamases : influência da esfera de coordenação do ZnII sobre a reatividade e interação com AuI/III: Mimetics of metallo-beta-lactamases : ZnII coordination sphere influence over reactivity and interaction with AuI/III. [Thesis]. Universidade Estadual de Campinas; 2019. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/334507

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Oueslati, Saoussen. Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS.

Degree: Docteur es, Microbiologie, 2019, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2019SACLS483

► Les antibiotiques, et plus particulièrement les β-lactamines, furent pendant longtemps considérés comme l’arme absolue pour le traitement des infections bactériennes, du fait de leur efficacité,… (more)

▼ Les antibiotiques, et plus particulièrement les β-lactamines, furent pendant longtemps considérés comme l’arme absolue pour le traitement des infections bactériennes, du fait de leur efficacité, leur bonne tolérance et de leur faible coût. Cependant, les bactéries ont développé des mécanismes de résistance, y compris vis-à-vis des β-lactamines possédant le spectre d’activité le plus large, les carbapénèmes. Ces derniers sont considérés comme les antibiotiques de derniers recours pour le traitement des infections sévères à bacilles à Gram négatif en milieu hospitalier. Chez les entérobactéries, cette résistance émergente aux carbapénèmes est principalement due à l’expression d’enzymes appelées les carbapénèmases capables d’inactiver les carbapénèmes. L’émergence exponentielle à l’échelle mondiale de ces entérobactéries productrices de carbapénèmases (EPC) constitue un problème majeur de santé publique. Actuellement, les carbapénémases les plus répandues dans le monde sont les KPC (Klebsiella pneumoniae carbapenemase), NDM-1 (New Delhi metallo- β- lactamase) et OXA-48 (Oxacillinase). La première KPC a été identifiée en 1996 aux Etats- Unis, NDM-1 en 2009 en Suède chez une patiente en provenance d’Inde et OXA-48 en 2003 en Turquie. En France, les carbapénèmases de type OXA-48 sont largement majoritaires et représentent près de 70% des EPC. Ainsi, le retentissement de leur dissémination et le besoin de développer de nouveaux inhibiteurs capables d’inactiver les carbapénèmases se fait de plus en plus pressante.Cette thèse a pour objectif de mieux comprendre le mode d’ action de ces 3 carbapénèmases d’un point de vue moléculaire et biochimique, afin d’ identifier les éléments structuraux nécessaires à leur fonctionnement, mais aussi de poser les bases du développement de « pan-inhibiteurs » et de nouveaux outils de diagnostics. Pour cela, la caractérisation biochimique des carbapénèmases de type KPC, NDM et OXA-48, de leurs variants naturels et de mutants générés in vitro a été entreprise. Il a pu être mis en exergue l’implication de résidus spécifiques et d’éléments structuraux nécessaires à l’ hydrolyse des carbapénèmes. L ’ étude cristallographique et RMN ainsi que l’étude in silico (modélisation) de ces enzymes et de leurs mutants respectifs, nous a permis de mieux comprendre le mode d’ interaction enzyme- substrat. Nous avons ainsi pu comprendre les bases de la capacité impressionnante de ces carbapénèmases à s’adapter et à évoluer en fonction des pressions de sélections exercées.En collaborations avec différentes équipes de chimistes nous avons développés différentes séries de molécules « pan-inhibiteurs » capables d’inhiber les 3 classes de carbapénèmases. Ainsi nous avons montré un effet inhibiteur de certains composés de la famille des flavonoïdes dont la myrécétine, molécule la plus active. Nous avons également identifié une série de composés, les imidazolines, possédant un effet pan-inhibiteur… Advisors/Committee Members: Naas, Thierry (thesis director).

Subjects/Keywords: Beta-Lactamases; Carbapénèmase; Inhibiteurs; Biochimie; Beta-Lactamases; Carbapenemase; Inhibitors; Biochemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Oueslati, S. (2019). Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2019SACLS483

Chicago Manual of Style (16^th Edition):

Oueslati, Saoussen. “Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS.” 2019. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 07, 2021. http://www.theses.fr/2019SACLS483.

MLA Handbook (7^th Edition):

Oueslati, Saoussen. “Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS.” 2019. Web. 07 Mar 2021.

Vancouver:

Oueslati S. Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2019. [cited 2021 Mar 07]. Available from: http://www.theses.fr/2019SACLS483.

Council of Science Editors:

Oueslati S. Caractérisation moléculaire et biochimique des carbapénèmases les plus répandues chez les Entérobactéries associées à des infections sévères en vue de développer de nouveaux inhibiteurs : MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF THE MOST POPULAR CARBAPENEMASES IN ENTEROBACTERIES ASSOCIATED WITH SEVERE INFECTIONS IN ORDER TO DEVELOP NEW INHIBITORS. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2019. Available from: http://www.theses.fr/2019SACLS483

Universiteit Utrecht

8. Tiersma, Y. β-Lactamase-producing bacteria How can I resist you?.

Degree: 2013, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/286793

► In 1945 Alexander Fleming won the Nobel Prize for his discovery of the first antibiotic, penicillin, which is a natural β-lactam antibiotic. In an interview… (more)

Subjects/Keywords: β-lactamase-producing bacteria; β-Lactam antibiotics; Antibiotic resistance; β-Lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tiersma, Y. (2013). β-Lactamase-producing bacteria How can I resist you?. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/286793

Chicago Manual of Style (16^th Edition):

Tiersma, Y. “β-Lactamase-producing bacteria How can I resist you?.” 2013. Masters Thesis, Universiteit Utrecht. Accessed March 07, 2021. http://dspace.library.uu.nl:8080/handle/1874/286793.

MLA Handbook (7^th Edition):

Tiersma, Y. “β-Lactamase-producing bacteria How can I resist you?.” 2013. Web. 07 Mar 2021.

Vancouver:

Tiersma Y. β-Lactamase-producing bacteria How can I resist you?. [Internet] [Masters thesis]. Universiteit Utrecht; 2013. [cited 2021 Mar 07]. Available from: http://dspace.library.uu.nl:8080/handle/1874/286793.

Council of Science Editors:

Tiersma Y. β-Lactamase-producing bacteria How can I resist you?. [Masters Thesis]. Universiteit Utrecht; 2013. Available from: http://dspace.library.uu.nl:8080/handle/1874/286793

University of KwaZulu-Natal

9. Estaleva, Calvina Ernesto Langa. Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique.

Degree: 2016, University of KwaZulu-Natal

URL: https://researchspace.ukzn.ac.za/handle/10413/17698

► Antibiotic resistance is one of the main public health problems worldwide, reducing treatment options and increasing morbidity and mortality. The production of extendedspectrum β-lactamases (ESBLs),… (more)

▼ Antibiotic resistance is one of the main public health problems worldwide, reducing treatment options and increasing morbidity and mortality. The production of extendedspectrum β-lactamases (ESBLs), plasmid mediated (pAmpC) β-lactamases are the most important resistance mechanisms that hamper antimicrobial treatment of infections caused by Enterobacteriaceae. This study describes the detection and characterization of pAmpC- and/or ESBL-producing clinical isolates of Escherichia coli (n=230) from urine and blood samples at the Central Hospital of Maputo, Mozambique from midAugust to mid-November 2015. Antimicrobial susceptibility testing was performed by the disc diffusion method. Isolates with reduced susceptibility to cefotaxime and/ or ceftazidime (n=75) were subjected to phenotypic AmpC- and/or ESBL testing as well as PCR-detection of blaCTX-M, blaTEM, blaSHV, blaCMY, blaMOX, blaFOX and blaDHA. A total of 75/230 (32.6 %) isolates were ESBL positive, and twenty-five of these were pAmpC positive. The most prevalent ESBL and pAmpC were CTX-M (77%) and FOX (32%), respectively. Most CTX-M negative ESBL-strains were blaSHV positive indicating a SHV-ESBL-type. The presence of co-resistance (R and I) to clinically important antibiotics were also frequent; blood ciprofloxacin (CIP; n= 12/17: 70.6%), gentamicin (GEN; n= 8/17: 47.1 %) and trimethoprim-sulfamethoxazole (SXT; n= 17/17; 100%) and urine CIP (n=40/58; 68.9%), GEN (n= 27/58; 46.5 %) and SXT (n= 55/58; 94.8%). Multidrug resistance was observed in 17/17 (100 %) and 58/58 (100 %) blood and urinary isolates, respectively. ERIC-PCR analysis revealed a large genetic diversity of strains with some minor clusters indicating intra hospital spread. The study has shown that: (i) a large proportion of clinical isolates of E. coli from the urinary tract and blood cultures from the Central Hospital are pAmpC and/or ESBLproducing. (ii) CTX-Ms and FOX were the dominant ESBL- and pAmpC-types, respectively. (iii) All ESBL- and pAmpC-producing strains were MDR-strains only susceptible to antibiotics that are not easily available in the current location. The overall findings strongly support the urgent need for strengthened and rapid diagnostic services to guide correct treatment of serious life-threatening infections and improved infection control measurements. Advisors/Committee Members: Sundsfjord, Arnfinn Staale. (advisor), Essack, Sabiha Yusuf. (advisor), Zimba, Tomas Francisco. (advisor).

Subjects/Keywords: β-lactamases.; Antibiotic.; Enterobacteriaceae.; Escherichia coli.; Mozambique.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Estaleva, C. E. L. (2016). Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique. (Thesis). University of KwaZulu-Natal. Retrieved from https://researchspace.ukzn.ac.za/handle/10413/17698

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Estaleva, Calvina Ernesto Langa. “Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique.” 2016. Thesis, University of KwaZulu-Natal. Accessed March 07, 2021. https://researchspace.ukzn.ac.za/handle/10413/17698.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Estaleva, Calvina Ernesto Langa. “Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique.” 2016. Web. 07 Mar 2021.

Vancouver:

Estaleva CEL. Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique. [Internet] [Thesis]. University of KwaZulu-Natal; 2016. [cited 2021 Mar 07]. Available from: https://researchspace.ukzn.ac.za/handle/10413/17698.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Estaleva CEL. Extended spectrum B-lactamase and plasmid mediated AmpC resistance in clinical isolates of escherichia coli from the central hospital of Maputo, Mozambique. [Thesis]. University of KwaZulu-Natal; 2016. Available from: https://researchspace.ukzn.ac.za/handle/10413/17698

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas Tech University

10. Williams, Elizabeth. Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase.

Degree: 2012, Texas Tech University

URL: http://hdl.handle.net/2346/46937

► β-lactamases pose a great threat in clinical settings due to their resistance to classical antibiotics. The worst offenders of this group include class B β-lactamases,… (more)

Subjects/Keywords: Metallo-β-lactamases; Crystallization; Protein structure

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APA (6^th Edition):

Williams, E. (2012). Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase. (Thesis). Texas Tech University. Retrieved from http://hdl.handle.net/2346/46937

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Williams, Elizabeth. “Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase.” 2012. Thesis, Texas Tech University. Accessed March 07, 2021. http://hdl.handle.net/2346/46937.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Williams, Elizabeth. “Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase.” 2012. Web. 07 Mar 2021.

Vancouver:

Williams E. Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase. [Internet] [Thesis]. Texas Tech University; 2012. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/2346/46937.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Williams E. Crystallization of the Bacillus cereus 5/B/6 Metallo-β-lactamase. [Thesis]. Texas Tech University; 2012. Available from: http://hdl.handle.net/2346/46937

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Voulgari, Evangelia. Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια.

Degree: 2014, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)

URL: http://hdl.handle.net/10442/hedi/43655

► The present study has been focused on two main objectives on the one hand the detection andcharacterization of plasmid-mediated AmpC β-lactamases in Enterobacteriaceae, along withan… (more)

▼ The present study has been focused on two main objectives on the one hand the detection andcharacterization of plasmid-mediated AmpC β-lactamases in Enterobacteriaceae, along withan evaluation of the effectiveness of various inhibitors in their detection and an assessment ofa modified CLSI-ESBL test and on the other hand the investigation of novel carbapenemasegenes which have recently been introduced to the Greek region.A total of 105 Enterobacteriaceae isolates (K.pneumoniae, E.coli, K.oxytoca, P.mirabilis)collected over a 9 year period from 2004 to 2012, exhibiting reduced susceptibility orresistance either to cefoxitin (FOX) and/or cefotetan (CTT) along with reduced susceptibility or resistance to at least one extended spectrum cephalosporin were further investigated for thepresence of plasmid AmpC β-lactamases. Plasmid-mediated AmpCs, ESBLs and the VIMtypecarbapenemases were sought by PCR amplification and subjected to direct sequencing.Susceptibility testing was performed with disk diffusion and ertapenem MICs were evaluatedwith the Etest method. Clonal relationship was investigated by either enterobacterial repetitiveintergenic consensus PCR (ERIC-PCR) or repetitive sequence based PCR (REP-PCR). FourAmpC inhibitors, cloxacillin (CLOX), phenyl-boronic acid (PBA), 3-acetyl-phenyl-boronic acid(APA) and 3-amino-phenyl-boronic (APBA) acid were evaluated, the latter in two finalconcentrations (300 and 600 μg/disk) with FOX, CTT, ceftazidime (CAZ) and cefotaxime (CTX)as substrates. Finally a modified CLSI ESBL test with the use of the aforementioned inhibitors andCTX and CAZ was evaluated.Altogether 59 isolates harbored plasmid-mediated AmpCs, with 35 also co-producing ESBLs.The MOX-2 β-lactamase was identified with the highest frequency followed by the CMY-2enzyme. CMY-4, CMY-13 and CMY-31 were also detected along with three novel to theregion enzymes, DHA-1 and two new AmpCs a CMY-4-like and a MIR-2-like. All P.mirabilisbelonged to one clonal type, K.oxytoca isolates presented two distinct clonal types whileK.pneumoniae and E.coli isolates presented 8 and 11 clonal types respectively.FOX resistance was found to be a discriminating parameter performing better than CTT as aninitial screening tool. In regards to the confirmatory phenotypic AmpC disk assay, FOX incombination with APBA produced the best results, successfully identifying 57/59 isolates. Theproposed modified CLSI ESBL test provided a significantly better overall performance whenperformed with CLOX (sensitivity 91,4% and specificity 75%), PBA (100%, 75%) and APBA(97,1%, 79,1%) in comparison to the standard CLSI ESBL test (85,7%, 58,3%). APA as an inhibitor failed to enhance the modified CLSI ESBL test exhibiting a suboptimal sensitivity of54,3%. Between January 2010 and June 2013, 132 non-repetitive carbapenem-resistantEnterobacteriaceae isolates, which gave positive the modified Hodge test (ΜΗΤ) and werephenotypically suspected of metallo-β-lactamase production (MBL), were recovered frompatients hospitalized in Ioannina University Hospital. Molecular…

Subjects/Keywords: Καρβαπενεμάσες; AmpC β-λακταμάσες; Λακταμάσες; Αντοχή; Εντεροβακτηριοειδή; Carbapenemases; AmpC β-lactamases; Lactamases; Resistance; Enterobacteriaceae

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Voulgari, E. (2014). Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/43655

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Voulgari, Evangelia. “Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια.” 2014. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed March 07, 2021. http://hdl.handle.net/10442/hedi/43655.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Voulgari, Evangelia. “Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια.” 2014. Web. 07 Mar 2021.

Vancouver:

Voulgari E. Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10442/hedi/43655.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Voulgari E. Επιδημιολογική μελέτη και διερεύνηση πλασμιδιακών AmpC β-λακταμασών και καρβαπενεμασών στα εντεροβακτηριοειδή στην ελληνική επικράτεια. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. Available from: http://hdl.handle.net/10442/hedi/43655

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

12. Soroka, Daria. Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria.

Degree: Docteur es, Biochimie, 2016, Université Pierre et Marie Curie – Paris VI

URL: http://www.theses.fr/2016PA066432

►

Mycobacterium tuberculosis et Mycobacterium abscessus produisent les β-lactamases BlaC et BlaMab qui contribuent à la résistance intrinsèque de ces bactéries aux β-lactamines. Notre objectif est… (more)

▼

Mycobacterium tuberculosis et Mycobacterium abscessus produisent les β-lactamases BlaC et BlaMab qui contribuent à la résistance intrinsèque de ces bactéries aux β-lactamines. Notre objectif est de caractériser l’inhibition de ces β-lactamases par l’avibactam et le clavulanate pour contribuer au développement de nouveaux traitements. Nous avons déterminé le profil de substrat et d’inhibition de BlaMab ainsi que sa structure cristalline, révélant trois différences majeures avec BlaC. BlaMab a une activité supérieure à celle de BlaC pour toutes les β-lactamines sauf la céfoxitine qui est utilisée pour les infections dues à M. abscessus. BlaC est inhibée irréversiblement par le clavulanate et inefficacement par l’avibactam alors que BlaMab présente le comportement inverse impliquant une hydrolyse du clavulanate et une inhibition très rapide par l’avibactam. La structure de BlaMab diffère de celle de BlaC principalement par le remplacement du motif conservé SDN par SDG. L’introduction de SDG dans BlaMab et de SDN dans BlaC a montré que cette différence détermine le profil d’inhibition des β-lactamases. Une seule mutation peut donc entraîner l’émergence d’une résistance aux combinaisons d’une β-lactamine avec le clavulanate ou l’avibactam mais pas avec les deux inhibiteurs. L’avibactam et le clavulanate offrent donc des alternatives thérapeutiques en cas de résistance à l’un des inhibiteurs. Nous nous sommes également intéressés aux β-lactamines partenaires du clavulanate, pour le traitement de la tuberculose et montrer que la structure des carbapénèmes pouvait être optimisée pour améliorer l’inactivation des cibles et diminuer l’hydrolyse par BlaC.

Mycobacterium tuberculosis and Mycobacterium abscessus produce the β-lactamases BlaC and BlaMab that contribute to the intrinsic resistance of those bacteria to β-lactams. Our objective was to characterize the inhibition of these β-lactamases by avibactam and clavulanate in order to contribute to the development of new treatments. We have determined the inhibition and substrate profiles of BlaMab, as well as its crystal structure, revealing three major differences with BlaC. BlaMab is more active than BlaC with respect to hydrolysis of all β-lactams except cefoxitin, which is used for the treatment of infections due to M. abscessus. BlaC is inhibited irreversibly by clavulanate and inefficiently by avibactam. In contrast, BlaMab shows the opposite behavior involving hydrolysis of clavulanate and a rapid inhibition by avibactam. Structurally BlaC differs from BlaMab mainly by the replacement of the conserved motif SDN by SDG. The introduction of SDG in BlaMab and of SDN in BlaC revealed that this difference determines the inhibition profile of the β-lactamases. A single mutation can therefore lead to the emergence of resistance to the association of β-lactam with clavulanate or avibactam, but not to both associations. Thus, avibactam and clavulanate offer therapeutic alternatives in case of resistance to one of the two inhibitors. We have also investigated the β-lactam…

Advisors/Committee Members: Arthur, Michel (thesis director).

Subjects/Keywords: Avibactam; Β-lactamases; Carbapénème; Clavulanate; Mycobacterium abscessus; Mycobacterium tuberculosis; Avibactam; Β-lactamases; Carbapenem; 572.8

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Soroka, D. (2016). Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria. (Doctoral Dissertation). Université Pierre et Marie Curie – Paris VI. Retrieved from http://www.theses.fr/2016PA066432

Chicago Manual of Style (16^th Edition):

Soroka, Daria. “Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria.” 2016. Doctoral Dissertation, Université Pierre et Marie Curie – Paris VI. Accessed March 07, 2021. http://www.theses.fr/2016PA066432.

MLA Handbook (7^th Edition):

Soroka, Daria. “Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria.” 2016. Web. 07 Mar 2021.

Vancouver:

Soroka D. Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria. [Internet] [Doctoral dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. [cited 2021 Mar 07]. Available from: http://www.theses.fr/2016PA066432.

Council of Science Editors:

Soroka D. Rôle du motif SDN dans l'inhibition et l'activité des β-lactamases des mycobactéries : Role of the motif SDN in the inhibition and substrate specificities of β-lactamases from mycobacteria. [Doctoral Dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. Available from: http://www.theses.fr/2016PA066432

13. Boutal, Hervé. Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance.

Degree: Docteur es, Biochimie et biologie structurale, 2017, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2017SACLS499

► Les béta-lactamines sont les antibiotiques préférentiellement utilisés contre les bactéries Gram négatif responsables d’infections. La dissémination mondiale d’organismes produisant des béta-lactamases à spectre élargi (BLSE)… (more)

▼ Les béta-lactamines sont les antibiotiques préférentiellement utilisés contre les bactéries Gram négatif responsables d’infections. La dissémination mondiale d’organismes produisant des béta-lactamases à spectre élargi (BLSE) ou des carbapénémases est une préoccupation générale ainsi qu’une menace économique.Parmi ces organismes, les Entérobactéries jouent un rôle important dans les infections nosocomiales (ainsi que les infections communautaires pour E. coli). L’émergence et la dissémination d’Entérobactéries productrices de BLSE (E-BLSE), exprimant principalement des béta-lactamases de la famille des CTX-Ms, et dans une mesure plus inquiétante de carbapénémases (EPC), principalement les enzymes NDM, KPC, IMP, VIM et OXA-48, sont sans le moindre doute un problème de santé publique majeur.Les CTX-Ms hydrolysent les céphalosporines à large spectre et sont les BLSEs principalement rencontrées chez les Entérobactéries lors d’infections urinaires communautaires, mais aussi les bactériémies à E. coli qui peuvent en découler. Ces infections sévères sont traitées avec des carbapénèmes, considérés comme les antibiotiques de dernier recours. Malheureusement, leur utilisation croissante à soumis les entérobactéries à une pression de sélection conduisant à de plus en plus de souches montrant une sensibilité réduite aux carbapénèmes pouvant aboutir à un échec thérapeutique.Si l’on considère les possibilités de traitement limitées pour les E-BLSEs, que les EPCs sont souvent résistantes à plusieurs si ce n’est toutes les classes d’antibiotiques, et que pour certaines peu ou pas de traitements antibiotiques sont disponibles, leur rapide détection et identification sont essentielles. Des tests fiables sont nécessaires pour aider les cliniciens à, rapidement mettre en place des mesures de contrôle de ces infections, adapter les traitements antibiotiques et optimiser les stratégies de soins et leur issue favorable.Lors de la détection des E-BLSEs et des EPCs, il est aussi crucial d’identifier la béta-lactamase impliquée pour la mise en place d’une thérapie adaptée. Les méthodes basées sur la spécificité des anticorps sont sans aucun doute parmi les plus appropriées pour atteindre cet objectif.Pour répondre aux besoins actuels, les méthodes de détection des résistances ont antibiotiques doivent être peu coûteuses (coûts réduits des consommables et des équipements) et facile à mettre en place (technicité faible) pour l’utilisateur. C’est pourquoi nous avons décidé de développer des tests immunochromatographiques qui répondent parfaitement à ce cahier des charges. Pour atteindre cet objectif, nous avons produit des anticorps monoclonaux dirigés contre les CTX-Ms, et les familles de carbapénémases NDM, KPC, et OXA-48. Les tests immuno-chromatographiques correspondants ont été développés et validés. Nos tests sont robustes, facilement transférables dans une version commerciale et stables pour 24 mois sans réfrigération. Ils sont conviviaux, performants en termes de spécificité et sensibilité, et peu couteux, de 7€ (pour un mono-test) à… Advisors/Committee Members: Volland, Hervé (thesis director).

Subjects/Keywords: Béta lactamases; Bandelettes; Enterobactéries; Beta lactamases; Lateral flow immunoassay; Enterobacteriae

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APA (6^th Edition):

Boutal, H. (2017). Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLS499

Chicago Manual of Style (16^th Edition):

Boutal, Hervé. “Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 07, 2021. http://www.theses.fr/2017SACLS499.

MLA Handbook (7^th Edition):

Boutal, Hervé. “Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance.” 2017. Web. 07 Mar 2021.

Vancouver:

Boutal H. Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Mar 07]. Available from: http://www.theses.fr/2017SACLS499.

Council of Science Editors:

Boutal H. Développement et validation de tests de détection rapide de la résistance aux antibiotiques : Development and validation of rapid detection tests for antibiotic resistance. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLS499

14. Tanner, Carol. Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria.

Degree: 2019, University of Waterloo

URL: http://hdl.handle.net/10012/14601

► The majority of antibiotics prescribed for treatment of bacterial infections are β-lactam antibiotics. Resistance to these has evolved in a few different ways, notably by… (more)

▼ The majority of antibiotics prescribed for treatment of bacterial infections are β-lactam antibiotics. Resistance to these has evolved in a few different ways, notably by regulating permeability and by the expression of β-lactamases which hydrolyze the antibiotic before it reaches its target. Three of the classes of β-lactamases (classes A, C and D) are serine-β-lactamases (SBLs) and the fourth class (Class B) consists of metallo-β-lactamases (MBLs) that rely on one or two zinc ions for their catalytic activity. Bacteria producing β-lactamases that are capable of hydrolyzing the β-lactam bond in all of the classes of β-lactam antibiotics including penicillins, monobactams, cephalosporins and carbapenems are of great clinical concern. As a consequence of the increasing prevalence of resistance, there is much interest in the discovery of inhibitors for such clinically important β-lactamases as well as in the discovery of β-lactam antibiotics that are less susceptible to inactivation by β-lactamases. Described in this thesis are the kinetic properties of new chromogenic cephalosporin-type substrates that are susceptible to hydrolysis by clinically important SBLs and MBLs but that exhibit a much more pronounced colour change upon hydrolysis than does the commercially available and widely used chromogenic cephalosporin called nitrocefin. Some of these substrates also offer more favourable kinetic properties for assaying MBLs in vivo. Also in this thesis, biochemical as well as microbiological investigations of several classes of SBL and MBL inhibitors are describes as well as one class of cephalosporins that exhibit inhibition of MBLs and surprising antibacterial potency against certain clinically significant MBL-producing Gram negative bacteria. More specifically, 6-phosphonomethylpyridine-2-carboxylates (PMPCs) and a number of derivatives thereof, synthesized previously in this research group have been shown in this thesis research to be potent inhibitors (low to submicromolar Ki) of the major Class B1 MBLs, IMP-1, VIM-2, NDM-1 and SPM-1 as well as the Class B3 MBL L1, all of which are dizinc enzymes, and somewhat less potent inhibitors of the monozinc Class B2 MBL, SFH-1, which is of lesser clinical significance. These compounds that are expected to exhibit metal-binding characteristics were found to exhibit a time-dependent inhibition mechanism which fits a kinetic mechanism that is consistent with slow binding to the active site and even slower release of the inhibitor without expulsion of the metal ions form the MBL active site. Microbiological investigations were also carried out involving combinations of PMPCs with the carbapenem antibiotic meropenem and demonstrated an ability of the PMPCs to lower the MICs of meropenem against of MBL-producing clinical strains of Eschericia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia thus encouraging further research on even more potent PMPCs for potential clinical use in combination with carbapenems. …

Subjects/Keywords: β-lactamases; β-lactamase inhibitors; enzyme kinetics; antibiotics; cephalosporin

10 more images…

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APA (6^th Edition):

Tanner, C. (2019). Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/14601

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tanner, Carol. “Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria.” 2019. Thesis, University of Waterloo. Accessed March 07, 2021. http://hdl.handle.net/10012/14601.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tanner, Carol. “Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria.” 2019. Web. 07 Mar 2021.

Vancouver:

Tanner C. Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria. [Internet] [Thesis]. University of Waterloo; 2019. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10012/14601.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tanner C. Biochemical and Microbiological Investigations of Inhibitors for β-Lactamases from Human Pathogenic Bacteria. [Thesis]. University of Waterloo; 2019. Available from: http://hdl.handle.net/10012/14601

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universiteit Utrecht

15. Dohmen, W. Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae.

Degree: 2014, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/294832

► Extended Spectrum Beta-Lactamase-producing Enterobacteriaceae (ESBL-PE) are an emerging concern in public health. Antimicrobial use, hospitalization and foreign travel are associated with human carriage of ESBL-PE.… (more)

▼ Extended Spectrum Beta-Lactamase-producing Enterobacteriaceae (ESBL-PE) are an emerging concern in public health. Antimicrobial use, hospitalization and foreign travel are associated with human carriage of ESBL-PE. Duration of carriage with ESBL-PE can vary. The main objective of this thesis is to provide an overview of the current scientific knowledge on persistence of ESBL carriage in humans. In addition, risk factors for duration of ESBL carriage will be described. After a literature search, 14 studies met the criterion that duration of ESBL-PE was assessed. Eight studies were conducted in patients, two in NICU patients, and four in non-patients (travelers, adopted children, medical students). Approximately half of adult (hospitalized) patients carried ESBL-PE after 6 months (range 33-53%). After 12 months, this percentage was around 25%. Median carriage time was reported from 98 days till more than 9 months. For a minority of patients carriage time was more than three years. Prolonged carriage with ESBL-PE was associated with outpatient oral use of antibiotics, urine catheters, chronic wounds, immobility and percutaneous gastrostomy, E. coli phylogroup B2, and CTX-M group 9. In NICU patients, median carriage time was 12.5 months, but carriage persisted after 12 months for 5% of individuals. Prolonged duration was observed for K. pneumonia or K. oxytoca species compared to S. marcensens, antibiotic treatment and caesarian section. Of travelers, 24% carried ESBL-producing E. coli after 3-8 months. Mean carriage time for 22 adopted children from Mali was 9 months. Out of 41 Chinese medical students, 68% remained colonized for 4 months. Results vary greatly and are hard to compare or generalize for many reasons such as small sample size, different definitions for duration, persistence and clearance, absence of molecular information, selection bias, and global differences. A longer duration of carriage with ESBL-PE might influence the risk of carriage with ESBL-PE for the patient itself and transmission to household members and the general population. Routine screening and/or contact restriction is suggested for previously ESBL-PE positive patients. Perhaps focus should be more on prevention of transmission than on clearance, because clearance is hard to accomplish. To estimate duration of carriage with ESBL-PE in the general population, large studies are needed. Advisors/Committee Members: Heederik, D..

Subjects/Keywords: Extended-Spectrum Beta-Lactamases; Duration; Colonization

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dohmen, W. (2014). Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/294832

Chicago Manual of Style (16^th Edition):

Dohmen, W. “Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae.” 2014. Masters Thesis, Universiteit Utrecht. Accessed March 07, 2021. http://dspace.library.uu.nl:8080/handle/1874/294832.

MLA Handbook (7^th Edition):

Dohmen, W. “Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae.” 2014. Web. 07 Mar 2021.

Vancouver:

Dohmen W. Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae. [Internet] [Masters thesis]. Universiteit Utrecht; 2014. [cited 2021 Mar 07]. Available from: http://dspace.library.uu.nl:8080/handle/1874/294832.

Council of Science Editors:

Dohmen W. Duration of colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae. [Masters Thesis]. Universiteit Utrecht; 2014. Available from: http://dspace.library.uu.nl:8080/handle/1874/294832

16. SILVA JÚNIOR, Valdemir Vicente da. DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO .

Degree: 2014, Universidade Federal de Pernambuco

URL: http://repositorio.ufpe.br/handle/123456789/11503

► Pseudomonas aeruginosa é uma bactéria gram-negativa conhecida por causar infecções oportunistas em diversos sítios do corpo humano principalmente tendo como destaque as infecções das vias… (more)

▼ Pseudomonas aeruginosa é uma bactéria gram-negativa conhecida por causar infecções oportunistas em diversos sítios do corpo humano principalmente tendo como destaque as infecções das vias aéreas. Estes patógenos apresentam resistência intrínseca a várias classes de agentes antimicrobianos, e notável habilidade em adquirir outros mecanismos de resistência, como por exemplo, a ação de enzimas beta-lactamases. Os genes que codificam essas enzimas geralmente são adquiridos através de mecanismos de transferência genética intra e/ou interespécies. A ação dessas beta-lactamases juntamente com outros mecanismos de resistência é frequentemente a razão das falhas terapêuticas durante o tratamento das infecções. Sendo assim, o presente estudo visou determinar a frequência genotípica de beta-lactamases do tipo ESBL (Beta-lactamases de espectro estendido) em isolados de P.aeruginosa provenientes do Hospital das Clínicas de Pernambuco (HC-UFPE). Os 159 isolados tiveram seu DNA extraído através do kit Brazol. O DNA obtido da extração foi quantificado e diluído para então iniciar a pesquisa genética através da técnica de PCR. Os isolados foram selecionados para pesquisa molecular de acordo com o perfil de resistência. Para o gene blaTEM, 1,41% (1/71) apresentou positividade; com relação ao blaGES observou-se que 2 isolados dos 54 testados (3,92%) carreavam o gene, após sequenciamento e análise in silico verificou-se que se tratava da GES-1; a tipagem molecular por ERIC-PCR demonstrou que os dois isolados são geneticamente relacionados. Esses achados possuem importância epidemiológica molecular dado que o gene blaGES em P.aeruginosa ainda não foi descrito no nordeste Brasileiro e o gene blaTEM em P.aeruginosa não foi relatado no Brasil; e portanto, servem de alerta para uma possível disseminação desses genes que contribuem de forma expressiva na resistência apresentada por isolados de P.aeruginosa. Advisors/Committee Members: MACIEL, Maria Amélia Vieira (advisor), LOPES, Ana Catarina de Souza (advisor).

Subjects/Keywords: Pseudomonas aeruginosa; Beta-Lactamases; Farmacorresistência bacteriana

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APA (6^th Edition):

SILVA JÚNIOR, V. V. d. (2014). DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO . (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/11503

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

SILVA JÚNIOR, Valdemir Vicente da. “DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO .” 2014. Thesis, Universidade Federal de Pernambuco. Accessed March 07, 2021. http://repositorio.ufpe.br/handle/123456789/11503.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

SILVA JÚNIOR, Valdemir Vicente da. “DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO .” 2014. Web. 07 Mar 2021.

Vancouver:

SILVA JÚNIOR VVd. DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO . [Internet] [Thesis]. Universidade Federal de Pernambuco; 2014. [cited 2021 Mar 07]. Available from: http://repositorio.ufpe.br/handle/123456789/11503.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

SILVA JÚNIOR VVd. DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO . [Thesis]. Universidade Federal de Pernambuco; 2014. Available from: http://repositorio.ufpe.br/handle/123456789/11503

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Rio Grande do Sul

17. Magagnin, Cibele Massotti. Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370.

Degree: 2017, Universidade do Rio Grande do Sul

URL: http://hdl.handle.net/10183/179051

► Base teórica: As carbapenemases são β-lactamases capazes de hidrolisar os carbapenêmicos, importante opção terapêutica nas infecções causadas por enterobactérias. A carbapenemase OXA-48 e suas variantes… (more)

▼ Base teórica: As carbapenemases são β-lactamases capazes de hidrolisar os carbapenêmicos, importante opção terapêutica nas infecções causadas por enterobactérias. A carbapenemase OXA-48 e suas variantes estão entre as principais carbapenemases encontradas em Enterobacteriaceae disseminadas em todo o mundo. A OXA-370, que difere da OXA-48 por um único aminoácido, foi detectada pela primeira vez em 2013 na cidade de Porto Alegre, e até o momento só há relatos de sua detecção no Brasil. Objetivos: Caracterizar isolados produtores de OXA-370 quanto ao perfil de sensibilidade aos β-lactâmicos, sobretudo carbapenêmicos, e investigar o contexto genético em que o gene blaOXA-370 está inserido. Métodos: Foram avaliados isolados obtidos a partir de um estudo de vigilância para o monitoramento de enterobactérias com sensibilidade reduzida aos carbapenêmicos. A detecção dos genes de carbapenemases (blaIMP, blaKPC, blaGES, blaNDM, blaOXA-48-like e blaVIM) foi realizada por PCR Real Time HRM. Os isolados positivos para blaOXA-48-like foram confirmados por PCR convencional e os produtos foram purificados e sequenciados. A relação clonal dos isolados produtores de OXA-370 foi avaliada pela técnica de macrorrestrição do DNA seguido de PFGE e as concentrações inibitórias mínimas (CIMs) foram analisadas por E-test® e/ou microdiluição em caldo. Os plasmídeos foram extraídos por lise alcalina e inseridos em Escherichia coli TOP10 por eletroporação. Bibliotecas de DNA plasmidial foram preparadas utilizando-se o kit Nextera DNA e a seguir foram sequenciadas no sistema MiSeq. As sequências foram montadas utilizando-se o programa SeqMan NGen e os contigs foram alinhados utilizando-se o SeqMan Pro. A plataforma RAST foi utilizada para anotação automática das sequências e a curadoria manual foi realizada utilizando-se o programa ARTEMIS. As sequências completas dos plasmídeos foram comparadas as disponíveis no GenBank utilizando-se o BLAST. As sequências de nucleotídicas dos plasmídeos foram alinhadas utilizando-se o BioEdit. Resultados: Um total de 4.451 enterobactérias foram avaliadas, provenientes de 28 hospitais do Rio Grande do Sul no período de abril de 2013 a abril de 2015. O gene blaOXA-48-like foi detectado em 74 (2,5%) isolados não sensíveis a pelo menos um dos carbapenêmicos. Quanto à distribuição segundo a gênero e/ou espécie, o gene foi detectado em Enterobacter spp. (44,6% complexo E. cloacae e 2,7% E. aerogenes) e 7 Klebsiella spp. (31,1% K. pneumoniae e 6,7% K. oxytoca), seguido por Escherichia coli, (6,7%), Morganella morganii, (2,7%), Citrobacter freundii (1,3%), Proteus mirabilis (1,3%), Providencia stuartii (1,3 %) e Serratia spp. (1,3%). Estes isolados foram provenientes de cinco hospitais, sendo 67 (90,5%) do hospital onde o gene blaOXA-370 foi detectado pela primeira vez. O sequenciamento de blaOXA-48-like foi realizado em 52 isolados, incluindo E. cloacae, E. aerogenes, K. pneumoniae, K. oxytoca, E. coli e C. freundii; todos apresentando 100% de identidade com blaOXA-370. A PFGE revelou a presença de clones distintos… Advisors/Committee Members: Zavascki, Alexandre Prehn.

Subjects/Keywords: Enterobacteriaceae; Anti-infecciosos; Carbapenêmicos; Beta-lactamases

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Magagnin, C. M. (2017). Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/179051

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Magagnin, Cibele Massotti. “Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370.” 2017. Thesis, Universidade do Rio Grande do Sul. Accessed March 07, 2021. http://hdl.handle.net/10183/179051.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Magagnin, Cibele Massotti. “Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370.” 2017. Web. 07 Mar 2021.

Vancouver:

Magagnin CM. Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2017. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10183/179051.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Magagnin CM. Caracterização molecular de isolados da família Enterobacteriaceae produtores da β-Lactamase OXA-370. [Thesis]. Universidade do Rio Grande do Sul; 2017. Available from: http://hdl.handle.net/10183/179051

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong

18. Choy, Wai-kit. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong.

Degree: 2005, University of Hong Kong

URL: http://hdl.handle.net/10722/131546

Subjects/Keywords: Beta lactamases.; Enterobacteriaceae.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Choy, W. (2005). Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/131546

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Choy, Wai-kit. “Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong.” 2005. Thesis, University of Hong Kong. Accessed March 07, 2021. http://hdl.handle.net/10722/131546.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Choy, Wai-kit. “Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong.” 2005. Web. 07 Mar 2021.

Vancouver:

Choy W. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong. [Internet] [Thesis]. University of Hong Kong; 2005. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10722/131546.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Choy W. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of Providencia stuartii in Hong Kong. [Thesis]. University of Hong Kong; 2005. Available from: http://hdl.handle.net/10722/131546

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Geyer, Chelsie Nicole. Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli.

Degree: PhD, Medical Microbiology and Immunology (graduate program), 2014, Creighton University

URL: http://hdl.handle.net/10504/49894

► The prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae is increasing rapidly. CTX-M type β-lactamases are the most prominent ESBL family worldwide and are produced mainly by… (more)

▼ The prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae is increasing rapidly. CTX-M type β-lactamases are the most prominent ESBL family worldwide and are produced mainly by E. coli. blaCTX-M-14 and blaCTX-M-15 genes are the dominant alleles circulating worldwide. The massive spread of CTX-M-producing organisms in both clinical and community settings have resulted in the CTX-M pandemic. However, the reasons for the rapid dissemination of this resistance mechanism remain unknown. It has been suggested that the success of CTX-M-15-producing E. coli is due to its association with the uropathogenic clone, sequence type 131 (ST131) that combines both virulence and multi-drug resistance mechanisms. The goal of my research was to understand the molecular mechanism(s) that contributes to CTX-M-mediated resistance with a focus on the two most dominant allotypes. Such studies could unveil potential targets for the development of new antibiotic therapies.|Initial steady-state expression studies demonstrated that CTX-M-15 mRNA was 8- to 165-fold higher than CTX-M-14 mRNA levels in E. coli strains isolated from human urine specimens from various geographical locations. Both CTX-M-14 and CTX-M-15 producers shared the same two promoters and transcriptional start sites and contained one copy of blaCTX-M-14 or blaCTX-M-15 on large clinical plasmids. Analysis of the upstream promoter regions using promoter deletion clones demonstrated that the proximal promoter elements within the non-coding region of ISEcp1 were responsible for the β-lactam resistant phenotype. Therefore, it was hypothesized that the genetic background of ST131 contributed to the upregulation of CTX-M-15 mRNA levels.|To this hypothesis, K12 transformants were constructed to evaluate the contribution of chromosomally-encoded factor(s) on the increased CTX-M-15 transcript levels VI observed. It was further hypothesized that CTX-M-14 and CTX-M-15 with the same K12 wild type E. coli background would have equivalent steady-state expression levels. The CTX-M-15 K12 transformant still showed an 11-fold increase in mRNA expression compared to the CTX-M-14 K12 transformant. These data indicated that the sequence type of the isolates was not a determining factor for the differential expression of these genes. Therefore, either an intrinsic structural feature was controlling transcription initiation of CTX-M-15 or a plasmid-encoded factor was causing differences in steady-state mRNA expression. Clones were created using heterologous promoters to drive expression of blaCTX-M-14/15 which still showed an upregulation of CTX-M-15. CTX-M chimeric clones were constructed through PCR to evaluate if the 5′ or 3′ halves of the CTX-M-15 gene contained an intrinsic structural element that affected transcription initiation. Expression of these constructs demonstrated that an element within the 5′ end of CTX-M-15 may control transcription initiation.|Additional studies that examined the stability of the CTX-M-14 and CTX-M-15 transcripts indicated that mRNA… Advisors/Committee Members: Hanson, Nancy (advisor), Geyer, Chelsie Nicole (cuauthor).

Subjects/Keywords: beta-Lactamases – genetics; Escherichia coli – genetics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Geyer, C. N. (2014). Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli. (Doctoral Dissertation). Creighton University. Retrieved from http://hdl.handle.net/10504/49894

Chicago Manual of Style (16^th Edition):

Geyer, Chelsie Nicole. “Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli.” 2014. Doctoral Dissertation, Creighton University. Accessed March 07, 2021. http://hdl.handle.net/10504/49894.

MLA Handbook (7^th Edition):

Geyer, Chelsie Nicole. “Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli.” 2014. Web. 07 Mar 2021.

Vancouver:

Geyer CN. Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli. [Internet] [Doctoral dissertation]. Creighton University; 2014. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10504/49894.

Council of Science Editors:

Geyer CN. Multiple levels of regulation are associated with the production of CTX-M-14 and CTX-M-15 beta-lactamases in Escherichia coli. [Doctoral Dissertation]. Creighton University; 2014. Available from: http://hdl.handle.net/10504/49894

Nelson Mandela Metropolitan University

20. Gqunta, Kwanele. Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth.

Degree: Faculty of Science, 2014, Nelson Mandela Metropolitan University

URL: http://hdl.handle.net/10948/d1020944

► Multidrug resistant (MDR) extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant Gram-negative bacteria have become an international health issue limiting treatment options. The objective of this study was… (more)

▼ Multidrug resistant (MDR) extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant Gram-negative bacteria have become an international health issue limiting treatment options. The objective of this study was to determine the prevalence of carbapenem-susceptible (CS) and carbapenem-resistant (CR) Enterobacteriaceae, Acinetobacter baumannii and Pseudomonas aeruginosa and investigate clinical isolates for their resistant genes/ determinants. A total of 98 bacterial isolates (59 CS and 39 CR) were collected between February 2012 and February 2013 at NHLS, after being recovered from various clinical specimens from PE hospital complex. Antimicrobial susceptibility testing was performed using the VITEK 2® system, E-test and microbroth dilution method. PCR and DNA sequencing were used to investigate: (i) ESBLs: CTX-M, TEM, SHV and OXA-1; (ii) plasmidmediated quinolone resistance (PMQR) genes: qnrA, qnrB, qnrC, qnrD, qnrS, qepA and aac(6’)-lb-cr; (iii) Escherichia coli sequence type 131 (ST131); (iv) carbapenemases: NDM, VIM, IMP, KPC, BIC, SME, IMI, NMC-A, GES, OXA-23, OXA-24, OXA-48, OXA-51 and OXA-58; and (v) insertion sequence ISAba1 upstream blaOXA-23/-24/-51/-58 genes. Porin loss in CR isolates was determined by SDSPAGE while genetic relatedness between E. coli ST131 isolates was determined by pulsed-field gel electrophoresis (PFGE). MDR ESBL-producing Enterobacteriaceae (mainly K. pneumoniae) and CR A. baumannii isolates were recovered from neonatal/ infant specimens. The majority of CS and CR isolates were MDR, possessing multiple ESBL genotypes (CTX-M, TEM, SHV and OXA-1). ESBL variants identified included: CTX-M-1, CTX-M-3, CTX-M-15, CTX-M-22, CTX-M-9, CTX-M-14, TEM-1, SHV-1, SHV-11 and OXA-1. PMQRs identified included: aac(6’)- lb-cr, qnrB1, qnrB2, qnrB13 and qnrS1. Twelve of 21 (57.1 percent) E. coli isolates belonged to the ST131 clonal complex and were genetically diverse, mainly producing CTX-M-15. Carbapenem resistance mechanisms identified included: (i) OXA-23 preceded by ISAba1 in 10 A. baumannii and 2 P. aeruginosa isolates; (ii) IMI-2 carbapenemase in an E. asburiae isolate; and (iii) combination of porin loss and ESBL production in 1 K. pneumoniae and 1 E. coli isolate. This is the first report in South Africa describing the occurrence of CTX-M-9, CTX-M-22 and IMI-2 among Enterobacteriaceae; CTX-M-15 in A. baumannii; and OXA-23 in combination with OXA-51 in P. aeruginosa. However, resistance determinants could not be detected for 24 carbapenem-resistant isolates which requires further investigation.

Subjects/Keywords: Beta lactamases; Enterobacteriaceae – South Africa – Port Elizabeth

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APA (6^th Edition):

Gqunta, K. (2014). Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth. (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/d1020944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gqunta, Kwanele. “Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth.” 2014. Thesis, Nelson Mandela Metropolitan University. Accessed March 07, 2021. http://hdl.handle.net/10948/d1020944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gqunta, Kwanele. “Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth.” 2014. Web. 07 Mar 2021.

Vancouver:

Gqunta K. Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth. [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2014. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10948/d1020944.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gqunta K. Prevalence and molecular epidemiology of extended-spectrum beta-lactamase-producing and carbapenem-resistant enterobacteriaceae, acinetobacter baumannii and pseudomonas aeruginosa in Port Elizabeth. [Thesis]. Nelson Mandela Metropolitan University; 2014. Available from: http://hdl.handle.net/10948/d1020944

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

21. SILVA, Natália Regina Souza da. Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE .

Degree: 2015, Universidade Federal de Pernambuco

URL: http://repositorio.ufpe.br/handle/123456789/17069

► Staphlylococcus desenvolveu a resistência aos betalactâmicos através de dois principais mecanismos, a expressão das betalactamases e a produção de PBP2a, codificadas pelos genes blaZ e… (more)

Subjects/Keywords: Beta-Lactamases; Staphylococcus; Resistência Microbiana a medicamentos

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APA (6^th Edition):

SILVA, N. R. S. d. (2015). Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE . (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/17069

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

SILVA, Natália Regina Souza da. “Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE .” 2015. Thesis, Universidade Federal de Pernambuco. Accessed March 07, 2021. http://repositorio.ufpe.br/handle/123456789/17069.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

SILVA, Natália Regina Souza da. “Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE .” 2015. Web. 07 Mar 2021.

Vancouver:

SILVA NRSd. Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE . [Internet] [Thesis]. Universidade Federal de Pernambuco; 2015. [cited 2021 Mar 07]. Available from: http://repositorio.ufpe.br/handle/123456789/17069.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

SILVA NRSd. Análise da ocorrência do gene da betalactamase em isolados clínicos de staphylococcus spp. resistentes à meticilina procedentes de hospital universitário da cidade do Recife-PE . [Thesis]. Universidade Federal de Pernambuco; 2015. Available from: http://repositorio.ufpe.br/handle/123456789/17069

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

22. Gonzaga, Gonçalo Ribeiro Roberto. Nitro- e aminoflavonas como agentes antibacterianos .

Degree: 2016, Universidade de Aveiro

URL: http://hdl.handle.net/10773/17481

► Os flavonoides são um grupo extenso de compostos naturais presentes na Natureza, em particular nas plantas. Este tipo de compostos já demonstraram em várias instâncias… (more)

▼ Os flavonoides são um grupo extenso de compostos naturais presentes na Natureza, em particular nas plantas. Este tipo de compostos já demonstraram em várias instâncias possuir atividades biológicas muito diversas, desde atividade antioxidante, anticancerígena e até antibacteriana. Dos compostos pertencentes a esta família e que apresentam atividade antibacteriana destacam-se as flavonas. Na literatura, estão descritos vários mecanismos através dos quais elas exercem a sua capacidade bactericida. Para além disso, estas apresentam também a capacidade de atenuar a patogenicidade de várias bactérias. Face ao crescente número de espécies bacterianas resistentes a antibióticos, às potencialidades do núcleo de flavona e à reconhecida importância da presença de um anel β-lactâmico idealizou-se a síntese de flavonas contendo um anel β-lactâmico como substituinte e a avaliação da sua atividade antibacteriana. Assim sendo o trabalho descrito nesta dissertação envolve num primeiro passo a síntese de 2’-hidroxinitrocalconas através de uma reação de condensação aldólica entre 2’-hidroxiacetofenonas e benzaldeídos convenientemente substituídos. Estas são em seguida sujeitas a uma reação de ciclodesidrogenação, catalisada por iodo, originando as respetivas nitroflavonas, que por redução do grupo nitro originam as aminoflavonas. As aminoflavonas foram usadas como substratos em diversos estudos de reações de Reformatsky, com o objetivo de sintetizar os derivados contendo o anel β-lactâmico. Os compostos sintetizados foram todos caracterizados por espectroscopia de ressonância magnética nuclear (RMN) mono (RMN de 1H e 13C) e bidimensional (HSQC e HMBC). Em seguida descrevem-se os resultados obtidos na avaliação da atividade antibacteriana de derivados de flavona e 2’-hidroxicalcona. Os resultados mostram que alguns derivados apresentam atividade antibacteriana, como sejam os casos da 2’-hidroxi-3’-nitrocalcona (MIC = 64 μg/mL), da 4- amino-2’-hidroxicalcona (MIC = 16 μg/mL), da 8-aminoflavona (MIC = 32 μg/mL) e da 8-nitroflavona (MIC = 8 μg/mL). No final são apresentadas as conclusões gerais e apresentadas propostas para trabalhos futuros. Advisors/Committee Members: Pinto, Diana Cláudia Gouveia Alves (advisor), Silva, Artur Manuel Soares da (advisor).

Subjects/Keywords: Beta lactamases; Agentes antibacterianos; Flavonas; Calconas

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gonzaga, G. R. R. (2016). Nitro- e aminoflavonas como agentes antibacterianos . (Thesis). Universidade de Aveiro. Retrieved from http://hdl.handle.net/10773/17481

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gonzaga, Gonçalo Ribeiro Roberto. “Nitro- e aminoflavonas como agentes antibacterianos .” 2016. Thesis, Universidade de Aveiro. Accessed March 07, 2021. http://hdl.handle.net/10773/17481.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gonzaga, Gonçalo Ribeiro Roberto. “Nitro- e aminoflavonas como agentes antibacterianos .” 2016. Web. 07 Mar 2021.

Vancouver:

Gonzaga GRR. Nitro- e aminoflavonas como agentes antibacterianos . [Internet] [Thesis]. Universidade de Aveiro; 2016. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10773/17481.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gonzaga GRR. Nitro- e aminoflavonas como agentes antibacterianos . [Thesis]. Universidade de Aveiro; 2016. Available from: http://hdl.handle.net/10773/17481

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Manitoba

23. Simner, Patricia Jeanne. Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009.

Degree: Medical Microbiology, 2011, University of Manitoba

URL: http://hdl.handle.net/1993/4412

► The spread of resistance to the cephalosporins in the Enterobacteriaceae and more specifically within E. coli is a continuing cause of public health concern, with… (more)

▼ The spread of resistance to the cephalosporins in the Enterobacteriaceae and more specifically within E. coli is a continuing cause of public health concern, with such resistance increasingly seen in community- and nosocomial-acquired infections. Extended-spectrum ß-lactamase (ESBL) and AmpC ß-lactamase (AmpC) enzymes cause most cephalosporin resistance in E. coli by hydrolysis of the antimicrobial and continue to jeopardize patient outcome. The purpose of this thesis was to determine the prevalence of ESBL-producing Enterobacteriaceae and to molecularly characterize ESBL and AmpC producers found to be associated with the increasing cephalosporin resistance among E. coli within Canadian hospitals from 2005 to 2009. Isolates were collected as part of the Canadian Intensive Care Unit and Canadian Ward surveillance studies. ESBL and AmpC producers were molecularly characterized for resistance genes, virulence factors and phylogenetic groups. All strains were typed using PFGE and ESBL-producing E. coli were further typed by MLST. Plasmids bearing the ESBL and AmpC genes were characterized by BglII RFLP analysis and a multiplex PCR for replicon typing. ESBL-producing E. coli and K. pneumoniae and AmpC-producing E. coli were found to be firmly established in Canadian hospitals; whereas, ESBL-producing K. oxytoca and P. mirabilis have yet to emerge. Increasing resistance to several unrelated antimicrobials leading to multi-drug resistance among these pathogens is concerning. The successful dissemination of ESBL-producing E. coli in Canada occurs through a diversity of different mechanisms and does not correspond to a single ESBL determinant, or a single clone, or a single plasmid but rather through the combination of clonal spread of virulent strains and the acquisition of diverse ESBL-bearing plasmids. However, the predominance of CTX-M-15-producing E. coli in this study was mainly due to the virulent ST131 clone and the diverse IncFII plasmids bearing the blaCTX-M-15 gene. Whereas, horizontal transfer of genetically similar IncI1, IncA/C and IncK/B plasmids bearing blaCMY-2 and the clonal spread of virulent strains, including ST131 with ampC promoter/attenuator mutations, appears to be playing a role in the spread of AmpC-producing E. coli isolates in Canadian hospitals. The increasing prevalence of these multi-drug resistant pathogens in Canadian hospitals demonstrates the need for increased surveillance and understanding of these emerging pathogens. The continued surveillance will help guide proper infection control procedures and identify optimal treatment of these clinically important pathogens in Canadian hospitals. Advisors/Committee Members: Hoban, Daryl J. (Medical Microbiology) Zhanel, George G. (Medical Microbiology) (supervisor), Embree, Joanne (Medical Microbiology) Mulvey, Michael R. (Medical Microbiology) Worobec, Elizabeth (Microbiology) (examiningcommittee).

Subjects/Keywords: Beta-Lactamases; Escherichia coli; Canada; Enterobacteriaceae

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APA (6^th Edition):

Simner, P. J. (2011). Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009. (Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/4412

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Simner, Patricia Jeanne. “Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009.” 2011. Thesis, University of Manitoba. Accessed March 07, 2021. http://hdl.handle.net/1993/4412.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Simner, Patricia Jeanne. “Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009.” 2011. Web. 07 Mar 2021.

Vancouver:

Simner PJ. Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009. [Internet] [Thesis]. University of Manitoba; 2011. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/1993/4412.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Simner PJ. Prevalence of extended-spectrum β-lactamase-producing Enterobacteriaceae with focus on the molecular characterization of ESBL- and AmpC β-lactamase- producing Escherichia coli isolated in Canadian hospitals from 2005-2009. [Thesis]. University of Manitoba; 2011. Available from: http://hdl.handle.net/1993/4412

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Hong Kong

24. Shek, Hoi-leong. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong.

Degree: 2004, University of Hong Kong

URL: http://hdl.handle.net/10722/26596

Subjects/Keywords: Enterobacter.; Beta-lactamases.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Shek, H. (2004). Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong. (Thesis). University of Hong Kong. Retrieved from http://hdl.handle.net/10722/26596

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Shek, Hoi-leong. “Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong.” 2004. Thesis, University of Hong Kong. Accessed March 07, 2021. http://hdl.handle.net/10722/26596.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Shek, Hoi-leong. “Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong.” 2004. Web. 07 Mar 2021.

Vancouver:

Shek H. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong. [Internet] [Thesis]. University of Hong Kong; 2004. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10722/26596.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Shek H. Detection and characterization of extended-spectrum beta-lactamases among blood isolates of enterobacters in Hong Kong. [Thesis]. University of Hong Kong; 2004. Available from: http://hdl.handle.net/10722/26596

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Massey University

25. Lamb, Susan Elizabeth. The [beta]-lactamases of the marine genus Photobacterium.

Degree: MS, Microbiology, 1981, Massey University

URL: http://hdl.handle.net/10179/11668

► All naturally occurring isolates of all five species of the marine genus Photobacterium have β-lactamase activity. In this study, the β-lactamase from the laboratory strain… (more)

Subjects/Keywords: Photobacterium; Beta lactamases

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APA (6^th Edition):

Lamb, S. E. (1981). The [beta]-lactamases of the marine genus Photobacterium. (Masters Thesis). Massey University. Retrieved from http://hdl.handle.net/10179/11668

Chicago Manual of Style (16^th Edition):

Lamb, Susan Elizabeth. “The [beta]-lactamases of the marine genus Photobacterium.” 1981. Masters Thesis, Massey University. Accessed March 07, 2021. http://hdl.handle.net/10179/11668.

MLA Handbook (7^th Edition):

Lamb, Susan Elizabeth. “The [beta]-lactamases of the marine genus Photobacterium.” 1981. Web. 07 Mar 2021.

Vancouver:

Lamb SE. The [beta]-lactamases of the marine genus Photobacterium. [Internet] [Masters thesis]. Massey University; 1981. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10179/11668.

Council of Science Editors:

Lamb SE. The [beta]-lactamases of the marine genus Photobacterium. [Masters Thesis]. Massey University; 1981. Available from: http://hdl.handle.net/10179/11668

26. Kurpiel, Philip Marion. Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli.

Degree: PhD, Medical Microbiology and Immunology (graduate program), 2013, Creighton University

URL: http://hdl.handle.net/10504/47482

► Enterobacteriaceae that express plasmid-encoded AmpC β-lactamases can be resistant to third generation cephalosporins and β-lactam/β-lactamase inhibitor combinations. Infections by these bacteria are associated with increased… (more)

▼ Enterobacteriaceae that express plasmid-encoded AmpC β-lactamases can be resistant to third generation cephalosporins and β-lactam/β-lactamase inhibitor combinations. Infections by these bacteria are associated with increased patient morbidity and mortality. Little is known about how plasmid-encoded AmpC genes are regulated or expressed. The experiments described in this dissertation sought to determine mechanisms that influence the transcription of blaCMY-2; the most common plasmid-encoded AmpC β-lactamase gene found in E. coli worldwide. Four clinical piperacillin/tazobactam-susceptible E. coli parent strains carrying blaCMY-2 and twelve piperacillin/tazobactam-resistant mutants selected from the parent strains were the focus of study. It was hypothesized that sequence changes upstream of blaCMY-2 were driving increased blaCMY-2 expression and enabling resistance to piperacillin/tazobactam in the mutants. It was also hypothesized that transcription factors binding to sequence upstream of blaCMY-2 promoter regions were influencing expression. Three important findings were made testing these hypotheses. 1) It was found that only 33% of the piperacillin/tazobactam-resistant mutants were overexpressing blaCMY-2. No upstream sequence changes were found in blaCMY-2 overexpressing mutant strains. For all overexpression mutants, changes in blaCMY-2 transcript level were associated with increased copy number of their blaCMY-2 encoded plasmid. Two mutants with blaCMY-2 on a 100 kb IncI1 plasmid had point mutations in the inc antisense RNA gene that controls IncI1 copy number. 2) Examination of upstream sequence for two parent strains identified a novel divergent tandem blaCMY-2 arrangement flanking an IS5 insertion element. Strains with this feature had 2-fold higher blaCMY-2 expression than a single arrangement strain. 3) The transcriptional activator Rob was identified binding sequence upstream of the distal blaCMY-2 promoter sequence within the insertion element ISEcp1. Additional studies indicated Rob was activated by β-lactam exposure and therefore may enhance blaCMY-2 expression when β-lactams are present. Further work will be needed to determine how gene copy number and Rob play a role in β-lactam resistance among clinical E. coli strains carrying blaCMY-2 . Advisors/Committee Members: Hanson, Nancy (advisor), Kurpiel, Philip Marion (cuauthor).

Subjects/Keywords: beta-Lactamases – genetics; Escherichia coli – genetics; beta-Lactamases – genetics; Escherichia coli – genetics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kurpiel, P. M. (2013). Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli. (Doctoral Dissertation). Creighton University. Retrieved from http://hdl.handle.net/10504/47482

Chicago Manual of Style (16^th Edition):

Kurpiel, Philip Marion. “Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli.” 2013. Doctoral Dissertation, Creighton University. Accessed March 07, 2021. http://hdl.handle.net/10504/47482.

MLA Handbook (7^th Edition):

Kurpiel, Philip Marion. “Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli.” 2013. Web. 07 Mar 2021.

Vancouver:

Kurpiel PM. Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli. [Internet] [Doctoral dissertation]. Creighton University; 2013. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10504/47482.

Council of Science Editors:

Kurpiel PM. Mechanisms Involved in the Expression of the AmpC Beta-lactamase Gene blaCMY-2 in Escherichia coli: MECHANISMS INVOLVED IN THE EXPRESSION OF THE PLASMID-ENCODED AmpC β-LACTAMASE GENE blaCMY-2 IN E. coli. [Doctoral Dissertation]. Creighton University; 2013. Available from: http://hdl.handle.net/10504/47482

27. Fung, Liang. Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp.

Degree: Mestrado, Doenças Infecciosas e Parasitárias, 2013, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/5/5134/tde-09082013-115449/ ;

► A resistência aos carbapenêmicos em amostras de Pseudomonas aeruginosa e Acinetobacter spp aumentou na última década. Vários surtos causados por esses agentes já foram descritos… (more)

▼ A resistência aos carbapenêmicos em amostras de Pseudomonas aeruginosa e Acinetobacter spp aumentou na última década. Vários surtos causados por esses agentes já foram descritos no Brasil. O presente estudo comparou métodos fenotípicos de triagem de carbapenemase em P. aeruginosa e Acinetobacter spp. isolados de hemoculturas de pacientes internados no HC-FMUSP. Foram estudados 108 isolados de P. aeruginosa identificados por sistema automatizado Vitek® e 50 isolados Acinetobacter spp. identificados pelo método miniaturizado API20NE. A determinação inibitória mínima dos carbapenêmicos foi realizada pela técnica de microdiluição em caldo e a tipagem molecular pela técnica de eletroforese em campo pulsado (PFGE). Os genes codificadores de carbapenemase foram identificados por meio da técnica de reação em cadeia da polimerase (PCR) e foi avaliada a hidrólise de imipenem de todos os isolados positivos para esses genes. Sensibilidade, especificidade, valor preditivo negativo e positivo dos testes fenotípicos foram calculados usando como padrão-ouro a detecção dos genes codificadores das carbapenemases por PCR. Nos isolados de Acinetobacter spp, foram pesquisados os genes das oxacilinases, dos quais quarenta e nove (98%) apresentaram pela técnica de PCR genes codificadores da enzima Oxa-51-like, sendo que um isolado não apresentou essa enzima e após sequenciamento do gene codificador da porção 16S do RNA ribossomal, foi considerado da espécie A. calcoaceticus. Em trinta e oito (76%) dos isolados foi detectado o gene blaOXA-143, em nove (18%) foi detectado o gene blaOXA-23, sendo que sete desses isolados pertenciam ao mesmo clone. Apenas cinco (10%) isolados de Acinetobacter spp apresentaram o gene blaIMP-1. Para os isolados de P. aeruginosa o gene blaSPM-1 foi o mais frequente sendo identificado em vinte e um (19,4%) dos isolados e quatro (3,7%) foi identificado com o gene blaVIM-2. Nove dos vinte e um isolados positivo para gene blaSPM-1, apresentaram a mesma clonalidade. O gene codificador blaGES-5 foi encontrado em quatro (3,7%) dos isolados de P. aeruginosa. Dos vinte quatro isolados P. aeruginosa que apresentaram gene codificador da M?L, apenas um isolado não hidrolisou IMI entre os Acinetobacter spp e apenas dois dos cincos isolados positivos para o gene codificador de M?L, hidrolisaram o IMI e apresentaram inibição com o EDTA. Dos vários testes fenotípicos realizados, os melhores resultados foram observados com Etest® M?L para ambos microrganismos com sensibilidade de 100%, mas esse teste foi pouco específico. Para os isolados de Acinetobacter spp o melhor resultado foi observado com o teste de aproximação de disco de IMI com disco de ABM, que apresentou sensibilidade de 100% e especificidade de 71% e para P. aeruginosa foi a aproximação de disco de CAZ com um disco de EDTA, que apresentou sensibilidade de 48% e especificidade de 93%. O presente estudo verificou que não existe um único teste fenotípico que consiga identificar carbapenemases nesses isolados e que a performace dos testes varia de acordo com as… Advisors/Committee Members: Costa, Silvia Figueiredo.

Subjects/Keywords: Acinetobacter; Acinetobacter; Beta- lactamases; Beta-lactamases; Carbapenêmicos; Carbapenems; Pseudomonas aeruginosa; Pseudomonas aeruginosa

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Fung, L. (2013). Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5134/tde-09082013-115449/ ;

Chicago Manual of Style (16^th Edition):

Fung, Liang. “Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp.” 2013. Masters Thesis, University of São Paulo. Accessed March 07, 2021. http://www.teses.usp.br/teses/disponiveis/5/5134/tde-09082013-115449/ ;.

MLA Handbook (7^th Edition):

Fung, Liang. “Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp.” 2013. Web. 07 Mar 2021.

Vancouver:

Fung L. Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp. [Internet] [Masters thesis]. University of São Paulo; 2013. [cited 2021 Mar 07]. Available from: http://www.teses.usp.br/teses/disponiveis/5/5134/tde-09082013-115449/ ;.

Council of Science Editors:

Fung L. Detecção fenotípica e genotípica de carbapenemases em isolados de hemoculturas de Pseudomonas aeruginosa e Acinetobacter spp. [Masters Thesis]. University of São Paulo; 2013. Available from: http://www.teses.usp.br/teses/disponiveis/5/5134/tde-09082013-115449/ ;

28. Andrade, Leonardo Neves de. Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite.

Degree: Mestrado, Biociências Aplicadas à Farmácia, 2008, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-163953/ ;

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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… (more)

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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.

Advisors/Committee Members: Darini, Ana Lucia da Costa.

Subjects/Keywords: AmpC); AmpC); Beta-lactamases (ESBL; Beta-lactamases (ESBL; Enterobacteriaceae; Enterobactérias; Meningite; Meningitis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Andrade, L. N. d. (2008). Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-163953/ ;

Chicago Manual of Style (16^th Edition):

Andrade, Leonardo Neves de. “Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite.” 2008. Masters Thesis, University of São Paulo. Accessed March 07, 2021. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-163953/ ;.

MLA Handbook (7^th Edition):

Andrade, Leonardo Neves de. “Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite.” 2008. Web. 07 Mar 2021.

Vancouver:

Andrade LNd. Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite. [Internet] [Masters thesis]. University of São Paulo; 2008. [cited 2021 Mar 07]. Available from: http://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-163953/ ;.

Council of Science Editors:

Andrade LNd. Estudo fenotípico e molecular de beta-lactamases de espectro estendido e AmpC em enterobactérias isoladas de pacientes com suspeita de meningite. [Masters Thesis]. University of São Paulo; 2008. Available from: http://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-163953/ ;

Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ)

29. Xexaki, Anna. Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων.

Degree: 2019, Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ)

URL: http://hdl.handle.net/10442/hedi/47183

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The aim of this study was the isolation of b-lactams, quinolones and colistin resistant strains of Escherichia coli from broiler and laying hen farms and… (more)

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The aim of this study was the isolation of b-lactams, quinolones and colistin resistant strains of Escherichia coli from broiler and laying hen farms and the phenotypic and molecular investigation. In addition, the determination of their phylogenetic group and the investigation of possible factors, at farm level that may influence the occurrence of resistance in E. coli. During the study period, 317 isolates from broiler feces and 106 isolates from laying hen feces were collected, representing different regions of Greece with the highest poultry production. All the isolates were tested for antimicrobial susceptibilities to a panel of 22 antimicrobials using the disc diffusion method and the broth microdilution method. Phenotypic investigation was performed for the production of ESBL and AmpC b-lactamases. Finally, PCR was used for the detection of ESBL genes (blaTEM, blaSHV, blaCTX-M, blaOXA), AmpC genes (blaCIT, blaFOX, blaMOX, blaACC, blaEBC, blaDHA), PMQR genes (qnrA, qnrB, qnrS, oqxA, oqxB, acc(6’)-ib-cr), the mcr-1 gene and the classification of E. coli isolates into the four phylogenetic groups (A, B1, B2, D). In coclusion, this thesis demonstrated the high rates of quinolone resistance among poultry and the presence of plasmid-mediated quinolone resistance (PMQR) genes in them. The study of ESBL genes shows the prevalence of CTX-M, which is now the most common worldwide. Phenotypic detection for the production of ESBLs failed to detect their production in all the strains with confirmed presence of esbl genes. The presence of mcr-1 was confirmed in broilers. Last but not least, there seemed to be factors associated with the farm level that influence the occurence of antimicrobial resistance.

Ο σκοπός της παρούσας διατριβής ήταν η απομόνωση στελεχών Escherichia coli ανθεκτικών στις β-λακτάμες, στις κινολόνες και στην κολιστίνη από εκτροφές κρεοπαραγωγών ορνιθίων και αυγοπαραγωγών ορνίθων και η διερεύνηση του φαινότυπου και γενότυπου αντοχής. Επιπλέον, καθορίστηκαν οι φυλογενετικές ομάδες των στελεχών και η πιθανή ύπαρξη παραγόντων κινδύνου που σχετίζονται με τις συνθήκες εκτροφής και ευνοούν την εμφάνιση ανθεκτικών στελεχών. Στην μελέτη συμπεριλήφθηκαν 317 δείγματα περιττωμάτων από εκτροφές κρεοπαραγωγών ορνιθίων και 106 δείγματα περιττωμάτων από εκτροφές αυγοπαραγωγών ορνίθων, καλύπτοντας περιοχές της Ελλάδας στις οποίες βρίσκεται ο κύριος όγκος παραγωγής. Ο αρχικός έλεγχος των στελεχών συμπεριέλαβε τον καθορισμό της μικροβιακής αντοχής σε 22 αντιμικροβιακές ουσίες με τη μέθοδο της διάχυσης δισκίων αντιβιοτικών σε άγαρ και τη μέθοδο των διαδοχικών μικροαραιώσεων σε ζωμό, τις φαινοτυπικές δοκιμασίες για την παραγωγή β-λακταμασών και τις μοριακές μεθόδους ταυτοποίησης. Έτσι, η δοκιμασία της αλυσιδωτής αντίδρασης της πολυμεράσης (PCR) χρησιμοποιήθηκε για την ταυτοποίηση των γονιδίων που έφεραν ESBL(blaTEM, blaSHV, blaCTX-M, blaOXA), AmpC (blaCIT, blaFOX, blaMOX, blaACC, blaEBC, blaDHA), PMQR (qnrA, qnrB, qnrS, oqxA, oqxB, acc(6’)-ib-cr), για το γονίδιο mcr-1 καθώς και για την κατάταξη των στελεχών E. coli…

Subjects/Keywords: Β-λακταμάσες; Gram αρνητικά βακτήρια; Β-λακταμικά αντιμικροβιακά; Κολιστίνη; Κινολόνες; Extended-spectrum beta-lactamases (ESBL); Escherichia coli; Colistin; Quinolones

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Xexaki, A. (2019). Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων. (Thesis). Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ). Retrieved from http://hdl.handle.net/10442/hedi/47183

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xexaki, Anna. “Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων.” 2019. Thesis, Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ). Accessed March 07, 2021. http://hdl.handle.net/10442/hedi/47183.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xexaki, Anna. “Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων.” 2019. Web. 07 Mar 2021.

Vancouver:

Xexaki A. Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων. [Internet] [Thesis]. Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ); 2019. [cited 2021 Mar 07]. Available from: http://hdl.handle.net/10442/hedi/47183.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xexaki A. Εκτίμηση του επιπολασμού για την παρουσία ανθεκτικών σε β-λακτάμες δεικτών Escherichia coli σε υγιή πτηνά εκτροφών αυγοπαραγωγών ορνίθων και κρεοπαραγωγών ορνιθίων. [Thesis]. Aristotle University Of Thessaloniki (AUTH); Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ); 2019. Available from: http://hdl.handle.net/10442/hedi/47183

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

30. Gomes, Joana Raquel Almeida. Carbapenemases em bacilos de Gram negativo.

Degree: 2017, Universidade Fernando Pessoa

URL: https://www.rcaap.pt/detail.jsp?id=oai:bdigital.ufp.pt:10284/6636

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O aumento de bactérias resistentes a antibióticos envolvidas em doenças infeciosas é um dos temas mais preocupantes da atualidade. Em particular, tem sido alarmante o… (more)

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O aumento de bactérias resistentes a antibióticos envolvidas em doenças infeciosas é um dos temas mais preocupantes da atualidade. Em particular, tem sido alarmante o aumento de Enterobacteriaceae, Acinetobacter sp. e Pseudomonas sp. resistentes a antibióticos β-lactâmicos do grupo dos carbapenemos. A resistência aos carbapenemos em bacilos de Gram negativo está fundamentalmente associada a genes que codificam para carbapenemases, isto é, β-lactamases com capacidade para hidrólise sobre carbapenemos, inativando a sua ação. Atualmente existe uma grande diversidade de carbapenemases, existindo esquemas de classificação que facilitam o seu agrupamento de acordo com algumas características que partilham. Muitos dos genes que codificam para carbapenemases têm sido fundamentalmente associados a plasmídeos, o que contribui para a sua rápida disseminação entre diferentes grupos bacterianos e nichos (unidades de cuidados de saúde/comunidade). Adicionalmente, estes plasmídeos albergam também frequentemente genes de resistência a outras famílias de antibióticos (quinolonas, aminiglicosídeos, entre outros), conduzindo a fenótipos de MDR, XDR e PDR. Esta situação tem um impacto clínico assinalável, uma vez que fica não só comprometido o uso de antibióticos β-lactâmicos (muito eficazes e pouco tóxicos), mas também de antibióticos de outras famílias, no tratamento das infeções por bacilos de Gram negativo produtores de carbapenemases. A epidemiologia global de algumas espécies de bacilos de Gram negativo produtores de carbapenemases é hoje conhecida, embora existam diferenças geográficas assinaláveis. Nos últimos anos os isolados bacterianos produtores de carbapenemases têm-se disseminado globalmente, surgindo por isso uma preocupação cada vez maior face às elevadas taxas de morbilidade e mortalidade associadas. Trata-se de microrganismos associados a infeções nosocomiais graves, a elevadas taxas de mortalidade e de difícil tratamento, sendo muito escassas as opções terapêuticas eficazes. As evidências apontam que a medida mais eficaz no combate às infeções hospitalares é a higienização das mãos, sendo esta uma prática fundamental para a redução da disseminação da resistência bacteriana. Ao associar a isto medidas de limpeza e desinfeção de superfícies contribui-se de forma efetiva para evitar e minimizar o surgimento de reservatórios ambientais e fontes de infeção. Para evitar surtos hospitalares por estas bactérias podem ser feitos a rastreios de colonização intestinal. As bactérias produtoras de carbapenemases representam uma grande ameaça para a saúde humana em todo o mundo e constituem um dos problemas mais desafiadores para a contenção de doenças infeciosas nos próximos anos. Como alternativas terapêuticas para tratar infeções causadas por bactérias produtoras de carbapenemases restam as polimixinas (por exemplo, colistina) e a tigeciclina. As polimixinas permanecem ativas contra a maioria destes isolados multirresistentes, no entanto, já começam a surgir resistências à colistina decorrentes do aumento do seu uso.

The…

Advisors/Committee Members: Machado, Elisabete.

Subjects/Keywords: Antibióticos β-lactâmicos; Resistência a carbapenemos; β-lactamases; Carbapenemases; Metalo-β-lactamases; Enterobacteriaceae; Pseudomonas aeruginosa; Acinetobacter sp.; β-lactam antibiotics; Carbapenems resistance; β-lactamases; Carbapenemases; Metallo-β-lactamases; Enterobacteriaceae; Pseudomonas aeruginosa; Acinetobacter sp.; Domínio/Área Científica::Ciências Médicas::Medicina Básica

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APA (6^th Edition):

Gomes, J. R. A. (2017). Carbapenemases em bacilos de Gram negativo. (Thesis). Universidade Fernando Pessoa. Retrieved from https://www.rcaap.pt/detail.jsp?id=oai:bdigital.ufp.pt:10284/6636

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gomes, Joana Raquel Almeida. “Carbapenemases em bacilos de Gram negativo.” 2017. Thesis, Universidade Fernando Pessoa. Accessed March 07, 2021. https://www.rcaap.pt/detail.jsp?id=oai:bdigital.ufp.pt:10284/6636.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gomes, Joana Raquel Almeida. “Carbapenemases em bacilos de Gram negativo.” 2017. Web. 07 Mar 2021.

Vancouver:

Gomes JRA. Carbapenemases em bacilos de Gram negativo. [Internet] [Thesis]. Universidade Fernando Pessoa; 2017. [cited 2021 Mar 07]. Available from: https://www.rcaap.pt/detail.jsp?id=oai:bdigital.ufp.pt:10284/6636.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gomes JRA. Carbapenemases em bacilos de Gram negativo. [Thesis]. Universidade Fernando Pessoa; 2017. Available from: https://www.rcaap.pt/detail.jsp?id=oai:bdigital.ufp.pt:10284/6636

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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