subject:(antibiotic)

1. Durmus, Naside Gozde. Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites.

Degree: PhD, Biomedical Engineering, 2013, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:320579/

► Antibiotic resistance and the lack of new antimicrobial therapies create significant challenges for the treatment of infections. Therefore, there is an urgent clinical need to… (more)

▼ Antibiotic resistance and the lack of new antimicrobial therapies create significant challenges for the treatment of infections. Therefore, there is an urgent clinical need to develop novel treatments targeting bacterial biofilms to reduce the risk of infection, without resorting to antibiotics. The goal of this thesis is, for the first time, to integrate two novel approaches, i.e. nanotechnology and metabolic stimulation, to eradicate antibiotic-resistant biofilms. The metabolic microenvironment of the biofilms has been manipulated to improve the antibacterial properties of superparamagnetic iron oxide nanoparticles (SPION) as well as nanorough device surfaces. First, it has been shown that engineered nanoscale topographies provide surfaces that are more resistant to bacterial growth than conventional polyvinyl chloride (PVC). In addition, for the first time, the presence of fructose on the nanorough PVC further decreased the planktonic S. aureus growth and biofilm formation, without use of any antibiotics. Moreover, a simple, broad-spectrum and low-cost dual-sided approach which uses SPION in combination with metabolites (i.e., fructose, glucose, and mannitol) has been developed as an alternative to existing antibacterial strategies. This strategy offers further improved efficacy of SPION against persistent gram-positive and gram-negative bacteria infections by manipulating the biofilm metabolic microenvironment, creating a new nanotechnology-driven approach. Further, biofilm eradication by the engineered SPION was significantly better than vancomycin, the antibiotic of last resort. In addition, it has been demonstrated that SPION conjugated with antibacterial silver salts exhibit strong eradication properties against the antibiotic-resistant (MRSA) biofilms. Antibacterial properties of silver-conjugated SPION were further improved when an external magnetic field was applied as their magnetic core enabled them to penetrate into the biofilms. This thesis, for the first time, highlighted the importance of biofilm metabolic microenvironment for the nanotechnology-driven approaches. It is envisioned that these simple and inexpensive approaches could lead to novel alternative treatments to the only current clinical option, vancomycin, which MRSA has started to develop a resistance towards. These novel nanotechnology-driven approaches can lead to successful clinical outcomes in terms of minimizing infections, longer medical device lifetimes, and decreasing antibiotic usage. Advisors/Committee Members: Webster, Thomas (Director), Webster, Thomas (Reader), Tripathi, Anubhav (Reader), Sun, Shouheng (Reader), Morgan, Jeffrey (Reader), Tripathi, Anubhav (Director).

Subjects/Keywords: antibiotic resistance

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Durmus, N. G. (2013). Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:320579/

Chicago Manual of Style (16^th Edition):

Durmus, Naside Gozde. “Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites.” 2013. Doctoral Dissertation, Brown University. Accessed January 16, 2021. https://repository.library.brown.edu/studio/item/bdr:320579/.

MLA Handbook (7^th Edition):

Durmus, Naside Gozde. “Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites.” 2013. Web. 16 Jan 2021.

Vancouver:

Durmus NG. Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites. [Internet] [Doctoral dissertation]. Brown University; 2013. [cited 2021 Jan 16]. Available from: https://repository.library.brown.edu/studio/item/bdr:320579/.

Council of Science Editors:

Durmus NG. Enhanced Efficacy of Nanotechnology-Driven Approaches against Antibiotic-Resistant Biofilms in the Presence of Metabolites. [Doctoral Dissertation]. Brown University; 2013. Available from: https://repository.library.brown.edu/studio/item/bdr:320579/

2. Vecchione, James J. Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance.

Degree: PhD, Chemistry, 2011, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:11186/

► The growing number of drug-resistant pathogenic bacteria is an impending public health crisis. Unfortunately, the rate at which pathogenic bacteria are developing resistance to our… (more)

Subjects/Keywords: Antibiotic Resistance

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Vecchione, J. J. (2011). Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:11186/

Chicago Manual of Style (16^th Edition):

Vecchione, James J. “Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance.” 2011. Doctoral Dissertation, Brown University. Accessed January 16, 2021. https://repository.library.brown.edu/studio/item/bdr:11186/.

MLA Handbook (7^th Edition):

Vecchione, James J. “Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance.” 2011. Web. 16 Jan 2021.

Vancouver:

Vecchione JJ. Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance. [Internet] [Doctoral dissertation]. Brown University; 2011. [cited 2021 Jan 16]. Available from: https://repository.library.brown.edu/studio/item/bdr:11186/.

Council of Science Editors:

Vecchione JJ. Using Chemical, Genetic, and Biochemical Approaches to Understand and Circumvent Antibacterial Drug Resistance. [Doctoral Dissertation]. Brown University; 2011. Available from: https://repository.library.brown.edu/studio/item/bdr:11186/

University of Debrecen

3. Kristínardóttir, Ester. Comparison of antibiotic consumption in the three internal medicine departments .

Degree: DE – Általános Orvostudományi Kar, 2014, University of Debrecen

URL: http://hdl.handle.net/2437/194847

► Because of the excessive usage of antibiotics, development of resistant bacteria emerges and therefore monitoring of antibiotic resistance and consumption is essential. Data about antibiotic… (more)

Subjects/Keywords: Antibiotic; Comparison

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Kristínardóttir, E. (2014). Comparison of antibiotic consumption in the three internal medicine departments . (Thesis). University of Debrecen. Retrieved from http://hdl.handle.net/2437/194847

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):

Kristínardóttir, Ester. “Comparison of antibiotic consumption in the three internal medicine departments .” 2014. Thesis, University of Debrecen. Accessed January 16, 2021. http://hdl.handle.net/2437/194847.

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

MLA Handbook (7^th Edition):

Kristínardóttir, Ester. “Comparison of antibiotic consumption in the three internal medicine departments .” 2014. Web. 16 Jan 2021.

Vancouver:

Kristínardóttir E. Comparison of antibiotic consumption in the three internal medicine departments . [Internet] [Thesis]. University of Debrecen; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/2437/194847.

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

Council of Science Editors:

Kristínardóttir E. Comparison of antibiotic consumption in the three internal medicine departments . [Thesis]. University of Debrecen; 2014. Available from: http://hdl.handle.net/2437/194847

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

4. García Cazorla, Yolanda. Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.

Degree: 2018, Universidad de Cantabria

URL: http://hdl.handle.net/10902/14718

► ABSTRACT: Antibiotic resistance has become a pressing public health concern. The main mechanism for the dissemination of resistance genes is the horizontal transfer during conjugation.… (more)

▼ ABSTRACT: Antibiotic resistance has become a pressing public health concern. The main mechanism for the dissemination of resistance genes is the horizontal transfer during conjugation. Hence, the search for conjugation inhibitors (COINs) is paramount in the fight against the spread of resistances. In this pursuit, only unsaturated fatty acids had been described as COINs. Here, we define 2-bromopalmitic acid (2-BP) as a specific COIN. 2-BP is a palmitate analog without any unsaturation in its aliphatic chain which acts as inhibitor of many membrane-associated enzymes. The carboxylic group of COINs is essential for its effectivity. However, inhibition is not due to the presence of double or triple bonds in these compounds but, indirectly, by the conformation COINs can acquire upon binding to their molecular target. We identify the VirB11 homolog in the conjugative plasmid R388, the traffic ATPase TrwD, as their molecular target. VirB11 form hexameric rings in which each monomer has a C-terminal catalytic region (CTD) and a N-terminal region that interacts with the cytoplasmic site of the membrane (NTD) connected both of them by a flexible linker. Biochemical and structural characterizations define a non-competitive inhibition where COINs bind to a pocket comprised by NTD and linker, preventing the pivoting movement of NTD over CTD which, in turn, result in a reduction of TrwD ATPase activity. Interestingly, COINs are liberally incorporated into bacterial membranes, replacing palmitic acid as the major component. We determine that TrwD binds palmitic acid, thus facilitating its interaction with the membrane. Altogether, our data suggest that COINs bind TrwD at a site that is otherwise occupied by palmitic acid, albeit they differ in the contacts involved in the interaction. As a result, COINs affect the interaction of TrwD with the membrane. For a further understand of the conjugative process, we visualized the process in real time using fluorescent protein fusions to the main players in the conjugative system. Localization of the proteins suffers dramatic changes in the presence or absence of the rest of the component of the Type IV secretion system (T4SS). Moreover, by using fluorescent constructs of SeqA, a probe that binds hemimethylated DNA, we have found, surprisingly, that more than one event of conjugation takes place at a particular time. Additionally, we identify the formation of a weak complex between TrwD and the relaxase TrwC. TrwD presents structural homology to chaperones of the ClpB/Hsp 104 family, hence TrwD could play a chaperone activity during the transport of the pilot protein TrwC. In short, our results do not only contribute to a better understanding of VirB11 proteins and the conjugative process but also may open a new avenue for the rational design of more potent and effective drugs to control dissemination of antibiotic resistance genes. Advisors/Committee Members: Cabezón Navarro, María Elena (advisor), Universidad de Cantabria (other).

Subjects/Keywords: Antibiotic resistance

10 more images…

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

García Cazorla, Y. (2018). Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. (Doctoral Dissertation). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/14718

Chicago Manual of Style (16^th Edition):

García Cazorla, Yolanda. “Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.” 2018. Doctoral Dissertation, Universidad de Cantabria. Accessed January 16, 2021. http://hdl.handle.net/10902/14718.

MLA Handbook (7^th Edition):

García Cazorla, Yolanda. “Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos.” 2018. Web. 16 Jan 2021.

Vancouver:

García Cazorla Y. Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. [Internet] [Doctoral dissertation]. Universidad de Cantabria; 2018. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10902/14718.

Council of Science Editors:

García Cazorla Y. Inhibition of the conjugative traffic ATPase TrwD by fatty acid derivatives: Inhibición de la ATPasa conjugativa TrwD por derivados de ácidos grasos. [Doctoral Dissertation]. Universidad de Cantabria; 2018. Available from: http://hdl.handle.net/10902/14718

University of Illinois – Urbana-Champaign

5. Cox, Courtney Lynne. Strategies for thiazole/oxazole-modified microcin discovery.

Degree: PhD, Microbiology, 2015, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/88284

► Natural products continue to be an important source of therapeutically-relevant compounds. With the advent of inexpensive genome sequencing it has become apparent that bacteria produce… (more)

▼ Natural products continue to be an important source of therapeutically-relevant compounds. With the advent of inexpensive genome sequencing it has become apparent that bacteria produce a larger array of natural products than was previously believed. This new wealth in sequence data has potential to be helpful for the discovery of novel compounds by using genome mining. Although strategies of genome mining have become more efficient and capable of identifying novel biosynthetic gene clusters, it remains difficult to correlate gene clusters with natural products. In this dissertation I discuss limitations with the current methods of genome mining and correlating individual natural products with gene clusters. Furthermore, I characterize a rapidly growing family of natural products, the thiazole/oxazole-modified microcins (TOMMs), and discuss novel methods used to correlate the gene clusters to natural products from this family of metabolites. In chapter 2, I establish the sequence diversity and structural capability of bacteria and archaea to produce TOMM natural products. This genome mining characterization was used to identify nine novel classes of TOMMs, including one class from archaeal producers. In chapter 3, I discuss the utilization of genetic techniques to identify and isolate the TOMM natural product from the archaeal species Sulfolobus acidocaldarius. I demonstrate that although genetic manipulation has been previously used for the identification of natural products, comparative metabolomics is difficult to use for routine identification of low-abundance natural products such as the TOMM from S. acidocaldarius. Very few methods have been created to identify natural products from particular gene clusters. Therefore, in chapter 4, I discuss the creation of a novel method for the rapid identification of natural products following bioinformatics prioritization of antibiotic producing strains. This method utilizes the combination of genome mining and the chemical reactivity of natural products to discover new compounds. Dehydrated amino acids are modified residues commonly found in natural products such as TOMMs. I utilize the mild electrophilic chemical reactivity of dehydrated amino acids to label these natural products using a soft nucleophilic probe. These labeled natural products were easily detected using comparative mass spectrometry. Bacterial strains were prioritized by the genome mining established in chapter 2 to reduce the screening time to find a novel natural product. This dissertation presents the addition of novel genome mining and natural product discovery techniques to increase the discovery and production of therapeutically-relevant compounds. Advisors/Committee Members: Mitchell, Douglas A. (advisor), Mitchell, Douglas A (Committee Chair), Whitaker, Rachel J. (committee member), Olsen, Gary J. (committee member), van der Donk, Wilfred A. (committee member).

Subjects/Keywords: antibiotic discovery

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Cox, C. L. (2015). Strategies for thiazole/oxazole-modified microcin discovery. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/88284

Chicago Manual of Style (16^th Edition):

Cox, Courtney Lynne. “Strategies for thiazole/oxazole-modified microcin discovery.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 16, 2021. http://hdl.handle.net/2142/88284.

MLA Handbook (7^th Edition):

Cox, Courtney Lynne. “Strategies for thiazole/oxazole-modified microcin discovery.” 2015. Web. 16 Jan 2021.

Vancouver:

Cox CL. Strategies for thiazole/oxazole-modified microcin discovery. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/2142/88284.

Council of Science Editors:

Cox CL. Strategies for thiazole/oxazole-modified microcin discovery. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/88284

University of Houston

6. Dwibedi, Nilanjana 1979-. Parents’ Expectation to Receive Antibiotic Prescription for Children.

Degree: PhD, Pharmacy Administration, 2012, University of Houston

URL: http://hdl.handle.net/10657/503

► Background: The Centers for Disease Control indicated that in 2009, 90 million prescriptions were written for antibiotics in the United States, with half of those… (more)

▼ Background: The Centers for Disease Control indicated that in 2009, 90 million prescriptions were written for antibiotics in the United States, with half of those being "unnecessary or inappropriate". The highest rate of antibiotic use was evident in children younger than 15 years old. Physician’s perception of parents’ expectation to receive antibiotic prescription for their children is a significant predictor of overprescribing antibiotics. Objective: The objective was to manipulate two factors (parents’ ‘perceived benefits of using antibiotics’ and their ‘perceived barriers to visit doctors without any expectation of antibiotic prescription’) and then evaluate whether their level of expectation would change after the manipulation. Methods: A prospective experimental study was conducted using a structured data collection instrument. The purpose of the experiment was to manipulate two variables, perceived barriers and perceived benefits using four scenarios and keep other factors constant. Each subject viewed four situations and expectation associated with each situation was evaluated. Subjects who had at least one child (age ≤ 5 years) during the study and who could speak, read and write English were selected for the study. Data were collected at shopping malls and parks in Houston, TX. Descriptive analyses and repeated measures mixed method covariance adjusted analyses were performed using SAS® 9.3. The a-priori significance level was set as 0.05 for all tests conducted. Results: A total of 300 complete surveys were considered for analyses. The mean age for the sample was 30.36 (± 7.04) years; females represented 55.7% of the sample. The mean general expectation score (before reading any scenario) to receive antibiotic prescription for children was 53.6 (± 25.7). The repeated measure mixed methods analyses indicated that there was 12 point reduction (p < 0.0001) in expectation score after removing perceived barriers from the situational scenarios. Almost 16 point decrease (p < 0.0001) in expectation score was observed after removing perceived benefits from the scenario. There was 18 point decrease (p < 0.0001) in expectation score after removing perceived barriers and perceived benefits from the situational scenario. The study result also indicated that general expectation toward an antibiotic prescription, training in the healthcare field and parents’ preference for communication had significant effect on parents’ expectation. Conclusions: Perceived barriers, perceived benefits alone and in combination have effect on parents’ expectation to receive antibiotic prescription for children. Policy makers as well as intervention programs should consider these factors to enhance successful reduction of antibiotic expectations. Advisors/Committee Members: Sansgiry, Sujit S. (advisor), Johnson, Michael L. (committee member), Essien, Ekere James (committee member), Abughosh, Susan M. (committee member), Mehta, Paras D. (committee member).

Subjects/Keywords: Parental expectations; Antibiotic prescription; Antibiotic for children

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Dwibedi, N. 1. (2012). Parents’ Expectation to Receive Antibiotic Prescription for Children. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/503

Chicago Manual of Style (16^th Edition):

Dwibedi, Nilanjana 1979-. “Parents’ Expectation to Receive Antibiotic Prescription for Children.” 2012. Doctoral Dissertation, University of Houston. Accessed January 16, 2021. http://hdl.handle.net/10657/503.

MLA Handbook (7^th Edition):

Dwibedi, Nilanjana 1979-. “Parents’ Expectation to Receive Antibiotic Prescription for Children.” 2012. Web. 16 Jan 2021.

Vancouver:

Dwibedi N1. Parents’ Expectation to Receive Antibiotic Prescription for Children. [Internet] [Doctoral dissertation]. University of Houston; 2012. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10657/503.

Council of Science Editors:

Dwibedi N1. Parents’ Expectation to Receive Antibiotic Prescription for Children. [Doctoral Dissertation]. University of Houston; 2012. Available from: http://hdl.handle.net/10657/503

University of Manitoba

7. Fabra Prieto, Juan Camilo. Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa.

Degree: Chemistry, 2017, University of Manitoba

URL: http://hdl.handle.net/1993/32747

► This project focuses on developing tobramycin-moxifloxacin antibiotics, connected through an aliphatic tether, and evaluates its optimal length. The initial protocol had several shortcomings: the hybrid… (more)

Subjects/Keywords: Antibiotic Resistance; Pseudomonas Aeruginosa; Antibiotic Hybrids

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Fabra Prieto, J. C. (2017). Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/32747

Chicago Manual of Style (16^th Edition):

Fabra Prieto, Juan Camilo. “Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa.” 2017. Masters Thesis, University of Manitoba. Accessed January 16, 2021. http://hdl.handle.net/1993/32747.

MLA Handbook (7^th Edition):

Fabra Prieto, Juan Camilo. “Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa.” 2017. Web. 16 Jan 2021.

Vancouver:

Fabra Prieto JC. Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa. [Internet] [Masters thesis]. University of Manitoba; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1993/32747.

Council of Science Editors:

Fabra Prieto JC. Synthesis and properties of tobramycinmoxifloxacin hybrid antibiotics linked at position C5 of tobramycin for overcoming resistance in Pseudomonas aeruginosa. [Masters Thesis]. University of Manitoba; 2017. Available from: http://hdl.handle.net/1993/32747

University of Waterloo

8. Scott, Bradley. Daptomycin: studies on its action mode and on bacterial resistance with model membranes.

Degree: 2016, University of Waterloo

URL: http://hdl.handle.net/10012/10480

► Bacterial resistance to antibiotics is one of the most serious problems facing medicine today. Recently, reports have appeared describing bacteria that are resistant to daptomycin… (more)

▼ Bacterial resistance to antibiotics is one of the most serious problems facing medicine today. Recently, reports have appeared describing bacteria that are resistant to daptomycin (dap), an important antibiotic used against systemic infections caused by various Gram-positive (Gram+) bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). This has caused considerable concern amongst the medical community. With few medicines being developed to replace them, research on antibiotics of last resort is imperative. Dap is a branched, cyclic lipodepsipeptide consisting of a 10-amino acid macrolactone ring to which is attached an exocyclic tripeptide bearing a decanoyl acyl tail. Its activity is calcium-dependent. The action mode best substantiated involves the killing of bacteria through specific interaction with phosphatidylglycerol (PG) in their cell membranes, followed by the formation of oligomeric, cation-selective pores and dissipation of membrane potential. The successive steps of the action mode have been investigated using fluorescence-based assays in model membranes. The steps include, 1) calcium-mediated binding of monomers to PG at the outer leaflet; 2) formation of oligomers; 3) formation of pores through equilibration and alignment of oligomers across both membrane leaflets. The assay fluorophores include the intrinsically fluorescent kynurenine residue in dap, and various environmentally sensitive labels attached to dap by chemical modification. The objective of this work was to investigate three topics: the means by which lysyl-phosphatidylglycerol (LPG) disrupts the action mode of dap, the means through which dap induces toxicity in humans, and the characterization of synthetic dap analogs, including an acyl-linked dimer. LPG is of interest because its increased formation is a known resistance mechanism for many cationic antimicrobial peptides (CAMPs); it is also correlated to resistance to dap specifically. A potential component in dap-induced toxicity is presence of phosphatidylserine (PS) in mammalian tissues. PS is a major phospholipid, and was investigated due to its anionic properties, which may emulate bacterial PG. The characterization of synthetic dap analogs allows for the study of the structure-activity relationship (SAR) of dap. The LPG, PS and characterization studies were pursued using the aforementioned fluorescence assays on a model membrane system using large unilamellar vesicles (LUV; liposomes), and antibacterial activity assays as needed. LUVs may be substituted with Bacillus subtilis L-forms (cell wall deficient bacteria) when necessary. Deviations in the assay results on LPG liposomes give insight into the action mode step(s) impeded in LPG-mediated bacterial resistance. The success or failure of the assays on PS membranes gives insight into the mechanism of toxicity via potential PS-mediated dap binding and permeabilization of mammalian cells. Characterization of the SAR of dap may lead to potential pharmacological improvements. Understanding these topics may also…

Subjects/Keywords: daptomycin; antibiotic; fluorescence; antibiotic resistance; L-form

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Scott, B. (2016). Daptomycin: studies on its action mode and on bacterial resistance with model membranes. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/10480

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):

Scott, Bradley. “Daptomycin: studies on its action mode and on bacterial resistance with model membranes.” 2016. Thesis, University of Waterloo. Accessed January 16, 2021. http://hdl.handle.net/10012/10480.

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

MLA Handbook (7^th Edition):

Scott, Bradley. “Daptomycin: studies on its action mode and on bacterial resistance with model membranes.” 2016. Web. 16 Jan 2021.

Vancouver:

Scott B. Daptomycin: studies on its action mode and on bacterial resistance with model membranes. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10012/10480.

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

Council of Science Editors:

Scott B. Daptomycin: studies on its action mode and on bacterial resistance with model membranes. [Thesis]. University of Waterloo; 2016. Available from: http://hdl.handle.net/10012/10480

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

Virginia Tech

9. Thames, Callie H. Excretion of Antibiotic Resistance Genes by Dairy Calves.

Degree: MS, Dairy Science, 2013, Virginia Tech

URL: http://hdl.handle.net/10919/19293

► Twenty-eight Holstein and crossbred calves of both genders were used to evaluate the effect of milk replacer antibiotics on abundance of selected antibiotic resistance genes… (more)

▼ Twenty-eight Holstein and crossbred calves of both genders were used to evaluate the effect of milk replacer antibiotics on abundance of selected antibiotic resistance genes (ARG) in the feces. Calves were blocked by breed, gender, and birth order, and assigned to one of three treatments at birth. Treatments were control (containing no antibiotics in the milk replacer), subtherapeutic (neomycin sulfate and oxytetracycline hydrochloride each fed at 10 mg/calf/d), and therapeutic (no antibiotics in the milk replacer until d 36, then neomycin sulfate and oxytetracycline hydrochloride each fed at 1000 mg/calf/d for 14 d). Calves were fed milk replacer twice daily at 0600 h and 1800 h. Fecal and respiratory scores and rectal temperatures were recorded daily. Calves were weighed at birth and weaning to calculate average daily gain. Beginning at six weeks of age fecal grab samples were collected from heifers at 0600 h, 1400 h, 2000 h, and 2400 h for 7 d, while bull calves were placed in metabolism crates for collection of all feces and urine. DNA was extracted from feces, and ARG corresponding to the tetracyclines (tetC, tetG, tetO, tetW, and tetX), macrolides (ermB, ermF), and sulfonamides (sul1, sul2) classes of antibiotics along with the class I integron gene, intI1, were measured by quantitative polymerase chain reaction (qPCR). No tetC or intI was detected. There was no significant effect of antibiotic treatment on the absolute abundance (gene copies/ g wet manure) of any of the ARG except ermF, which was lower in the antibiotic-treated calf manure probably because host bacterial cells carrying ermF were not resistant to tetracycline or neomycin. All ARG except tetC and intI were detectable in feces from 6 weeks onwards, and tetW and tetG significantly increased with time (P < 0.10), even in control calves. Overall, the majority of ARG analyzed for were present in the feces of the calves regardless of exposure to dietary antibiotic. Feed antibiotics had little effect on the ARG monitored; other methods for reducing the ARG pool should also be investigated. Advisors/Committee Members: Knowlton, Katharine F. (committeechair), James, Robert E. (committee member), Pruden, Amy (committee member).

Subjects/Keywords: antibiotic; antibiotic resistance gene; dairy calf

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Thames, C. H. (2013). Excretion of Antibiotic Resistance Genes by Dairy Calves. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/19293

Chicago Manual of Style (16^th Edition):

Thames, Callie H. “Excretion of Antibiotic Resistance Genes by Dairy Calves.” 2013. Masters Thesis, Virginia Tech. Accessed January 16, 2021. http://hdl.handle.net/10919/19293.

MLA Handbook (7^th Edition):

Thames, Callie H. “Excretion of Antibiotic Resistance Genes by Dairy Calves.” 2013. Web. 16 Jan 2021.

Vancouver:

Thames CH. Excretion of Antibiotic Resistance Genes by Dairy Calves. [Internet] [Masters thesis]. Virginia Tech; 2013. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10919/19293.

Council of Science Editors:

Thames CH. Excretion of Antibiotic Resistance Genes by Dairy Calves. [Masters Thesis]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/19293

University of Waterloo

10. Muraih, Jawad K. Mode of Action of Daptomycin, a Lipopeptide Antibiotic.

Degree: 2013, University of Waterloo

URL: http://hdl.handle.net/10012/7323

► Daptomycin is a lipopeptide antibiotic that contains 13 amino acids and an N-terminally attached fatty acyl residue. The antibiotic kills Gram-positive bacteria by membrane depolarization.… (more)

▼ Daptomycin is a lipopeptide antibiotic that contains 13 amino acids and an N-terminally attached fatty acyl residue. The antibiotic kills Gram-positive bacteria by membrane depolarization. It has long been assumed that the mode of action of daptomycin involves the formation of oligomers on the bacterial cell membrane; however, at the outset of my studies, this had not been experimentally demonstrated. In the work described in this thesis, I have used fluorescence energy transfer (FRET) between native daptomycin and an NBD-labeled daptomycin derivative to demonstrate that the antibiotic indeed forms oligomers on bacterial cell membranes. In a liposome model, oligomer formation depends on calcium and on phosphatidylglycerol (PG). The oligomer forms rapidly and is stable for a length of time longer than required for the bactericidal effect. Through variation of the ratio of FRET donor (native daptomycin) and acceptor (NBD-daptomycin), I have determined that the oligomer consists of approximately 6–7 molecules, or, depending on the structure of the oligomer, possibly up to twice that number. Oligomer formation on liposomes and on bacterial membranes was confirmed using excimer fluorescence of a perylene-labeled daptomycin derivative. Excimer fluorescence was also used to demonstrate a stoichiometric interaction between daptomycin and PG. It has previously been shown that the bactericidal activity of daptomycin requires calcium and correlates with the concentration of PG in the bacterial cell membrane; these requirements mirror those observed here for oligomer formation. Furthermore, membrane permeabilization is selective, and electron microscopy of bacterial membranes exposed to daptomycin has revealed no discontinuities or accretions of electron density. Both of these findings suggest formation of a small membrane lesion, which is compatible with the small size of the oligomer that was determined here. In conjunction with these previous findings, the experiments contained in my thesis strongly suggest that the oligomer is the bactericidal form of daptomycin.

Subjects/Keywords: Daptomycin; Oligomerization; Antibiotic

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Muraih, J. K. (2013). Mode of Action of Daptomycin, a Lipopeptide Antibiotic. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7323

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):

Muraih, Jawad K. “Mode of Action of Daptomycin, a Lipopeptide Antibiotic.” 2013. Thesis, University of Waterloo. Accessed January 16, 2021. http://hdl.handle.net/10012/7323.

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

MLA Handbook (7^th Edition):

Muraih, Jawad K. “Mode of Action of Daptomycin, a Lipopeptide Antibiotic.” 2013. Web. 16 Jan 2021.

Vancouver:

Muraih JK. Mode of Action of Daptomycin, a Lipopeptide Antibiotic. [Internet] [Thesis]. University of Waterloo; 2013. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10012/7323.

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

Council of Science Editors:

Muraih JK. Mode of Action of Daptomycin, a Lipopeptide Antibiotic. [Thesis]. University of Waterloo; 2013. Available from: http://hdl.handle.net/10012/7323

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

Texas A&M University

11. Imanpour, Sara. Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance.

Degree: PhD, Health Services Research, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158650

► Antibiotics touch upon almost all aspects of our modern life. They contribute towards increasing life expectancy by reducing the negative outcomes of bacterial infections. Unfortunately,… (more)

▼ Antibiotics touch upon almost all aspects of our modern life. They contribute towards increasing life expectancy by reducing the negative outcomes of bacterial infections. Unfortunately, antibiotics tend to lose their effectiveness over time due to the emergence of antibiotic resistant bacteria. The overuse, misuse, and over-prescription of antibiotics all lead to the development of antibiotic resistant bacteria. This dissertation is a series of three studies that build on each other, each addressing different aspects of the human and organizational factors associated with antibiotic overuse, misuse, and over-prescription in the United States. Study I: The first study focuses on the reasons for antibiotic over-prescription from the point of view of family medicine residents. This qualitative study strives to better understand why medical professional prescribe antibiotics in cases in which antibiotics are not necessary or not useful. The findings suggest that physicians’ behaviors of over-prescribing antibiotics are affected by the organizational conditions within the medical practice including the use of an antibiotic control system and by patients’ expectations. Study II: The second study assesses the potential associations between the duration of visit with a doctor and antibiotic prescriptions for viral infections in outpatient settings. The assessment was done by utilizing National Ambulatory Medical Care Survey data. The results from multivariate logistic regression showed that for every additional minute spent with a physician during an office visit, the mean probability of receiving unnecessary antibiotic prescriptions decreased by 2.4%. Study III: The third is a qualitative study of the general public’s experiences and awareness of antibiotic overuse and antibiotic resistance. Focus groups conducted with twenty people who have traveled into the United States from countries with unrestricted access to antibiotics revealed a paucity of knowledge and awareness of antibiotic resistance and appropriate antibiotic use that must be addressed for any antibiotic stewardship policy to be successful. Despite the very restrictive policies overseeing antibiotic use in the United States, physicians tend to over-prescribe antibiotics and patients often insist on receiving a prescription. The findings of these studies show the need to educate patients through healthcare providers about the consequences of antibiotic overuse and misuse. This would curb the rate of antibiotic overuse, over-prescription, and subsequently, antibiotic resistance. Advisors/Committee Members: McMaughan, Darcy (advisor), Bolin , Jane N (committee member), Morrisey, Michael A (committee member), DeSalvo, Bethany (committee member).

Subjects/Keywords: antibiotic; Health education

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Imanpour, S. (2016). Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158650

Chicago Manual of Style (16^th Edition):

Imanpour, Sara. “Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/158650.

MLA Handbook (7^th Edition):

Imanpour, Sara. “Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance.” 2016. Web. 16 Jan 2021.

Vancouver:

Imanpour S. Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/158650.

Council of Science Editors:

Imanpour S. Antibiotic Stewardship in the United States: Antibiotic Over-prescription, Factors Associated with Antibiotic Prescription, and People’s Awareness of Antibiotic Resistance. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158650

McMaster University

12. Spanogiannopoulos, Peter. Exploring Rifamycin Inactivation from the Soil Microbiome.

Degree: PhD, 2014, McMaster University

URL: http://hdl.handle.net/11375/16283

►

Our battle against pathogens has become a challenge due to the rise in antibiotic resistance and the dwindling number of new antibiotics entering the clinic.… (more)

▼

Our battle against pathogens has become a challenge due to the rise in antibiotic resistance and the dwindling number of new antibiotics entering the clinic. Most antibiotics owe their origins to soil bacteria, which have been producing these natural products for millennia. The rifamycins are products of actinomycetes and semisynthetic derivatives of these have been very successful in the clinic. Rifampin (RIF) has been a cornerstone agent against tuberculosis for over 50 years. In the clinic, pathogens typically develop RIF resistance by mutation of the drug. Nonetheless, a number of diverse RIF resistance mechanisms have been described, including enzymatic inactivation. Environmental bacteria are multidrug resistant, likely due to sharing the same niche as antibiotic producers and represent a reservoir of ancient resistance determinants. Furthermore, these resistance determinants have been linked to pathogens. Exploring the antibiotic resistome, the collection of all antibiotic resistance determinants from the global microbiota, reveals the diversity and evolution of resistance and provides insight on vulnerabilities of our current antibiotics. Herein, I describe a diverse collection of RIF-inactivating mechanisms from soil actinomycetes. I identified heretofore unknown RIF glycosyltransferase and RIF phosphotransferase genes (rgt and rph, respectively). RGT and RPH enzymes display broad rifamycin specificity and contribute to high-level resistance. Interestingly, RIF-sensitive Gram-positive pathogens are carriers of RPH, highlighting the existence of a ‘silent’ resistome in clinically relevant bacteria and emphasize the importance of studying resistance from environmental bacteria. Furthermore, I identified a conserved upstream DNA motif associated with RIF-inactivating genes from actinomycetes and demonstrate its role in RIF-responsive gene regulation. Finally, I explore the use of a RIF-resistance guided approach to identify novel rifamycin producing bacteria. This study expands the rifamycin resistome, provides evidence of vulnerabilities of our current arsenal of rifamycin antibiotics, and offers a strategy to identify new members of this family natural product family.

Thesis

Doctor of Science (PhD)

Advisors/Committee Members: Wright, Gerard D., Biochemistry and Biomedical Sciences.

Subjects/Keywords: Antibiotic resistance; Microbiology

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Spanogiannopoulos, P. (2014). Exploring Rifamycin Inactivation from the Soil Microbiome. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/16283

Chicago Manual of Style (16^th Edition):

Spanogiannopoulos, Peter. “Exploring Rifamycin Inactivation from the Soil Microbiome.” 2014. Doctoral Dissertation, McMaster University. Accessed January 16, 2021. http://hdl.handle.net/11375/16283.

MLA Handbook (7^th Edition):

Spanogiannopoulos, Peter. “Exploring Rifamycin Inactivation from the Soil Microbiome.” 2014. Web. 16 Jan 2021.

Vancouver:

Spanogiannopoulos P. Exploring Rifamycin Inactivation from the Soil Microbiome. [Internet] [Doctoral dissertation]. McMaster University; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11375/16283.

Council of Science Editors:

Spanogiannopoulos P. Exploring Rifamycin Inactivation from the Soil Microbiome. [Doctoral Dissertation]. McMaster University; 2014. Available from: http://hdl.handle.net/11375/16283

13. Rashid, Muhammad Mahmudur. Antibiotic resistance in different ecological niches in Bangladesh.

Degree: Ecology and Environmental Sciences, 2013, Umeå University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84193

► The rapid and wide scale environmental spread of multi-drug resistant bacteria is a seriousissue in recent years. Drug resistant bacteria have already occupied different… (more)

Subjects/Keywords: Antibiotic resistance; Bangladesh

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Rashid, M. M. (2013). Antibiotic resistance in different ecological niches in Bangladesh. (Thesis). Umeå University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84193

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):

Rashid, Muhammad Mahmudur. “Antibiotic resistance in different ecological niches in Bangladesh.” 2013. Thesis, Umeå University. Accessed January 16, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84193.

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

MLA Handbook (7^th Edition):

Rashid, Muhammad Mahmudur. “Antibiotic resistance in different ecological niches in Bangladesh.” 2013. Web. 16 Jan 2021.

Vancouver:

Rashid MM. Antibiotic resistance in different ecological niches in Bangladesh. [Internet] [Thesis]. Umeå University; 2013. [cited 2021 Jan 16]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84193.

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

Council of Science Editors:

Rashid MM. Antibiotic resistance in different ecological niches in Bangladesh. [Thesis]. Umeå University; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-84193

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

Arizona State University

14. Weeks, Jon W. Genetics of Functional AcrAB-TolC Tripartite Complex Assembly.

Degree: PhD, Microbiology, 2012, Arizona State University

URL: http://repository.asu.edu/items/15167

► Intrinsic antibiotic resistance is of growing concern in modern medical treatment. The primary action of multidrug resistant strains is through over-expression of active transporters which… (more)

▼ Intrinsic antibiotic resistance is of growing concern in modern medical treatment. The primary action of multidrug resistant strains is through over-expression of active transporters which recognize a broad range of antibiotics. In Escherichia coli, the TolC-AcrAB complex has become a model system to understand antibiotic efflux. While the structures of these three proteins (and many of their homologs) are known, the exact mechanisms of interaction are still poorly understood. By mutational analysis of the TolC turn 1 residues, a drug hypersensitive mutant has been identified which is defective in functional interactions with AcrA and AcrB. Antibiotic resistant revertants carry alterations in both TolC and AcrA act by stabilizing functional complex assembly and opening of the TolC aperture, as monitored by stability of a labile TolC mutant and sensitivity to vancomycin, respectively. Alterations in the AcrB periplasmic hairpin loops lead to a similar antibiotic hypersensitivity phenotype and destabilized complex assembly. Likewise, alterations in TolC which constitutively open the aperture suppress this antibiotic sensitivity. Suppressor alterations in AcrA and AcrB partially restore antibiotic resistance by mediating stability of the complex. The AcrA suppressor alterations isolated in these studies map to the three crystallized domains and it is concluded they alter the AcrA conformation such that it is permanently fixed in an active state, which wild type only transiently goes through when activated by AcrB. Through this genetic evidence, a direct interaction between TolC and AcrB which is stabilized by AcrA has been proposed. In addition to stabilizing the interactions between TolC and AcrB, AcrA is also responsible for triggering opening of the TolC aperture by mediating energy flow from AcrB to TolC. By permanently altering the conformation of AcrA, suppressor mutants allow defective TolC or AcrB mutants to regain functional interactions lost by the initial mutations. The data provide the genetic proof for direct interaction between AcrB and that AcrA mediated opening of TolC requires AcrB as a scaffold.

Subjects/Keywords: Microbiology; Antibiotic Efflux

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Weeks, J. W. (2012). Genetics of Functional AcrAB-TolC Tripartite Complex Assembly. (Doctoral Dissertation). Arizona State University. Retrieved from http://repository.asu.edu/items/15167

Chicago Manual of Style (16^th Edition):

Weeks, Jon W. “Genetics of Functional AcrAB-TolC Tripartite Complex Assembly.” 2012. Doctoral Dissertation, Arizona State University. Accessed January 16, 2021. http://repository.asu.edu/items/15167.

MLA Handbook (7^th Edition):

Weeks, Jon W. “Genetics of Functional AcrAB-TolC Tripartite Complex Assembly.” 2012. Web. 16 Jan 2021.

Vancouver:

Weeks JW. Genetics of Functional AcrAB-TolC Tripartite Complex Assembly. [Internet] [Doctoral dissertation]. Arizona State University; 2012. [cited 2021 Jan 16]. Available from: http://repository.asu.edu/items/15167.

Council of Science Editors:

Weeks JW. Genetics of Functional AcrAB-TolC Tripartite Complex Assembly. [Doctoral Dissertation]. Arizona State University; 2012. Available from: http://repository.asu.edu/items/15167

University of Melbourne

15. Hardefeldt, Laura Yvonne. Antimicrobial stewardship in Australian veterinary practices.

Degree: 2017, University of Melbourne

URL: http://hdl.handle.net/11343/198446

► Antimicrobial use by the veterinary profession has been coming under increasing scrutiny by medical, public health and government officials as the threat of antimicrobial resistance… (more)

▼ Antimicrobial use by the veterinary profession has been coming under increasing scrutiny by medical, public health and government officials as the threat of antimicrobial resistance becomes increasingly clear. The World Health Organisation has described antimicrobial resistance as one of the major public health challenges of our time. It is clear that at least some drug-resistant pathogens have evolved under selective pressure from antimicrobial use in agriculture and may be contributing significantly to resistance in clinical setting. Antimicrobial stewardship is the selection of the most appropriate antimicrobial for a given disease in a given animal, with the aim of reducing the risk of adverse effects in that animal, and reducing the likelihood of developing resistance on an individual level, on a farm level and on a national level. Currently none of the core elements of antimicrobial stewardship are widely available for veterinarians in Australia, and there is very sparse data available on which to base an antimicrobial stewardship program. This research project aims to address this paucity of data. A range of research methods were used to assess detailed antimicrobial use by veterinarians in Australia and the enablers and barriers to antimicrobial stewardship. These included quantitative methods such as surveys and analysis of pet insurance data, and qualitative methods such as interviews and focus groups. While antimicrobials with low importance rating were predominately used in all species, under-dosing and inappropriate timing of antimicrobial therapy were common particularly in horses and cattle. Few veterinary practices in Australia had antimicrobial stewardship policies in place, or were using antimicrobial use guidelines. The key barriers to implementing antimicrobial stewardship programs were a lack of antimicrobial stewardship governance structures, client expectations and competition between practices, the cost of microbiological testing, and a lack of access to education, training and antimicrobial stewardship resources. The enablers were, firstly, concern for the role of veterinary antimicrobial use in development of antimicrobial resistance in humans, secondly , a sense of pride in the service provided, and thirdly , preparedness to change prescribing practices. This research culminated in the development of a proposed antimicrobial stewardship policy and procedure documents, to enable veterinarians to institute antimicrobial stewardship programs that suit their individual practice requirements. However, it is likely that governance changes will be necessary to compel veterinary practice owners to implement antimicrobial stewardship on a large scale.

Subjects/Keywords: antibiotic; antimicrobial resistance

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Hardefeldt, L. Y. (2017). Antimicrobial stewardship in Australian veterinary practices. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/198446

Chicago Manual of Style (16^th Edition):

Hardefeldt, Laura Yvonne. “Antimicrobial stewardship in Australian veterinary practices.” 2017. Doctoral Dissertation, University of Melbourne. Accessed January 16, 2021. http://hdl.handle.net/11343/198446.

MLA Handbook (7^th Edition):

Hardefeldt, Laura Yvonne. “Antimicrobial stewardship in Australian veterinary practices.” 2017. Web. 16 Jan 2021.

Vancouver:

Hardefeldt LY. Antimicrobial stewardship in Australian veterinary practices. [Internet] [Doctoral dissertation]. University of Melbourne; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11343/198446.

Council of Science Editors:

Hardefeldt LY. Antimicrobial stewardship in Australian veterinary practices. [Doctoral Dissertation]. University of Melbourne; 2017. Available from: http://hdl.handle.net/11343/198446

University of Oklahoma

16. Lam, Anh. ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE.

Degree: PhD, 2020, University of Oklahoma

URL: http://hdl.handle.net/11244/325287

► Antibiotic resistance (AR) is a serious growing threat around the globe. There has been no new antibiotic class developed in the past 30 years, while… (more)

▼ Antibiotic resistance (AR) is a serious growing threat around the globe. There has been no new antibiotic class developed in the past 30 years, while antibiotic-resistant superbugs are emerging everywhere and becoming more and more life-threatening. In 2019, AR pathogens took away about 35,000 lives and infected over 2.8 million people a year in the United States alone. Experts predict that, by 2050, AR will be the top leading cause of death, claiming 10 million lives a year. Motivated and dedicated to thousands of families who lose their loved ones each year to antibiotic-resistant infections, our research lab studies the defense mechanisms of superbugs. Instead of finding a new antibiotic, we study how to remove their resistance using a potentiator called BPEI (branched polyethylenimine). BPEI is a chemical compound that can disable the resistance factors of superbugs while traditional antibiotics (i.e. amoxicillin) can now actively target the vulnerable pathogens. It is called “combination therapy”. My initial specific contribution is study to fight one of the most commonly clinical isolates of Staph infections—multidrug-resistant Staphylococcus epidermidis. Previously known as a harmless commensal species on human skin, Staphylococcus epidermidis is now the first-ranking causative agent of hospital-related infections, with 24% mortality. It has become resistant to many antibiotics and thus acquired the name MRSE (Methicillin- Resistant Staphylococcus epidermidis). Additionally, MRSE bacteria can form dangerous biofilms – extra layers of self-made material – that protects them from antibiotics and helps them live on inanimate surfaces like medical devices for weeks to months. Persistent biofilms are also a leading cause of chronic wound infections. In the United States, a cost of $2 billion/year is estimated for S. epidermidis vascular-catheter-related bloodstream infections. This resistance is mainly governed by a protein called PBP2a, which the susceptible Staph bacteria do not have. The protein PBP2a has a very low affinity for traditional β-lactam antibiotics, thereby making first-choice antibiotics ineffective. Here, the use of BPEI becomes effective because exposure to BPEI molecules inhibits the function of PBP2a of MRSE, and therefore making them susceptible to existing antibiotics. Many experiments and analyses were conducted by using multiple biochemical techniques including microtiter plate assays, growth and time-killing curves, bacterial colony forming units, visible and fluorescence spectroscopies, electron microscopies, Fourier-transform infrared spectroscopy, and mass spectrometry. Not only being effective against MRSE, BPEI can also broaden antibiotic spectrum against other bacterial species like MRSA, Pseudomonas aeruginosa, E. coli and their biofilms. Exact concentrations of each combination treatment were found for each bacterial strain. New mechanisms of action of BPEI against different bacteria and its effects on human inflammatory responses were also elucidated and reported in this… Advisors/Committee Members: Rice, Charles (advisor), Nanny, Mark (committee member), Wu, Si (committee member), Yang, Zhibo (committee member), Shao, Yihan (committee member).

Subjects/Keywords: Antibiotic resistance; polyethylenimine

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Lam, A. (2020). ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/325287

Chicago Manual of Style (16^th Edition):

Lam, Anh. “ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE.” 2020. Doctoral Dissertation, University of Oklahoma. Accessed January 16, 2021. http://hdl.handle.net/11244/325287.

MLA Handbook (7^th Edition):

Lam, Anh. “ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE.” 2020. Web. 16 Jan 2021.

Vancouver:

Lam A. ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE. [Internet] [Doctoral dissertation]. University of Oklahoma; 2020. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11244/325287.

Council of Science Editors:

Lam A. ANTIBIOTIC COMBINATION THERAPY AGAINST MULTIDRUG-RESISTANT STAPHYLOCOCCUS EPIDERMIDIS BIOFILMS AND BROADENING ANTIBIOTIC SPECTRUM USING POLYETHYLENIMINE. [Doctoral Dissertation]. University of Oklahoma; 2020. Available from: http://hdl.handle.net/11244/325287

University of Georgia

17. Keyes, Kathleen Fern. Evolution and ecology of florfenicol antibiotic resistance.

Degree: 2014, University of Georgia

URL: http://hdl.handle.net/10724/20362

► The evolution of antibiotic resistance has become a ubiquitous problem in both human and veterinary medicine. Florfenicol, a veterinary fluorinated analogue of thiamphenicol and chloramphenicol,… (more)

Subjects/Keywords: Florfenicol; Antibiotic; Antibiotic resistance; Antibiotic resistance genes; flo; Escherichia coli; Plasmids; Integrons; Poultry diseases

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Keyes, K. F. (2014). Evolution and ecology of florfenicol antibiotic resistance. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/20362

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):

Keyes, Kathleen Fern. “Evolution and ecology of florfenicol antibiotic resistance.” 2014. Thesis, University of Georgia. Accessed January 16, 2021. http://hdl.handle.net/10724/20362.

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

MLA Handbook (7^th Edition):

Keyes, Kathleen Fern. “Evolution and ecology of florfenicol antibiotic resistance.” 2014. Web. 16 Jan 2021.

Vancouver:

Keyes KF. Evolution and ecology of florfenicol antibiotic resistance. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10724/20362.

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

Council of Science Editors:

Keyes KF. Evolution and ecology of florfenicol antibiotic resistance. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/20362

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

Virginia Tech

18. Riquelme Breazeal, Maria Virginia. Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses.

Degree: PhD, Civil Engineering, 2016, Virginia Tech

URL: http://hdl.handle.net/10919/83419

► Outputs of human-derived chemicals and constituents to the environment, and shifts in these outputs, can result in unintended consequences to human and ecological health. One… (more)

▼ Outputs of human-derived chemicals and constituents to the environment, and shifts in these outputs, can result in unintended consequences to human and ecological health. One such shift is the advent of the modern antibiotic era, in which mass production and outputs of antibiotics, which are mostly naturally-derived microbial defense compounds and include a few synthetic antimicrobials, has profound implications for contributing to the spread of antibiotic resistance. Antibiotic resistance arises from mutations and/or sharing of antibiotic resistance genes (ARGs) among bacteria via horizontal gene transfer, with carriage of ARGs by pathogenic bacteria of particular concern to human health. While most attention to stopping the spread of antibiotic resistance has been devoted to the clinic, it is critical to consider the environmental origin, ecology and pathways by which antibiotic resistance spreads in order to develop comprehensive strategies to combat antibiotic resistance. In particular, wastewater treatment plants (WWTPs) represent a potentially key critical control point given that they receive antibiotic resistant bacteria (ARB) and ARGs from the population, which are then routed to activated sludge biological treatment, consisting of high density, highly active microbial populations. The research projects described in this dissertation aimed to explore the occurrence of ARGs in WWTPs, particularly WWTPs in developing countries representing the extremes of what is expected to be encountered in terms of potential to spread antibiotic resistance, and to improve and apply novel technologies for monitoring key markers of antibiotic resistance in WWTPs and affected environments. The pathogen Staphylococcus aureus and a corresponding ARG (methicillin resistance mecA gene) were chosen as model biocontaminants of concern due to their environmental and public health relevance. The results reported in Chapters 3-5 advance the knowledge of bio(nano)sensing techniques and highlight areas of promise and challenge. The results reported in Chapter 2 provided insight into the baseline levels of ARGs expected in a highly impacted WWTP in India, thereby highlighting the magnitude and global scale of the problem of antibiotic resistance as well as the need for innovative solutions. Advisors/Committee Members: Pruden, Amy (committeechair), Vikesland, Peter J. (committeechair), Hochella, Michael F. Jr. (committee member), Agah, Masoud (committee member).

Subjects/Keywords: Nanosensors; biosensors; antibiotic resistance; antibiotic resistance genes; ARGs; antibiotic resistant bacteria; ARB

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Riquelme Breazeal, M. V. (2016). Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/83419

Chicago Manual of Style (16^th Edition):

Riquelme Breazeal, Maria Virginia. “Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses.” 2016. Doctoral Dissertation, Virginia Tech. Accessed January 16, 2021. http://hdl.handle.net/10919/83419.

MLA Handbook (7^th Edition):

Riquelme Breazeal, Maria Virginia. “Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses.” 2016. Web. 16 Jan 2021.

Vancouver:

Riquelme Breazeal MV. Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses. [Internet] [Doctoral dissertation]. Virginia Tech; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/10919/83419.

Council of Science Editors:

Riquelme Breazeal MV. Improved monitoring of emerging environmental biocontaminants through (nano)biosensors and molecular analyses. [Doctoral Dissertation]. Virginia Tech; 2016. Available from: http://hdl.handle.net/10919/83419

Technical University of Lisbon

19. Monchique, Cláudia Raquel Oliveira. Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006.

Degree: 2013, Technical University of Lisbon

URL: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6229

►

Dissertação de Mestrado Integrado em Medicina Veterinária

O género Staphylococcus tem importância a nível clínico e económico, sendo que a emergência de estirpes meticilina resistente… (more)

▼

Dissertação de Mestrado Integrado em Medicina Veterinária

O género Staphylococcus tem importância a nível clínico e económico, sendo que a emergência de estirpes meticilina resistente e multirresistentes tornam-no num assunto atual em Medicina Humana e Veterinária. As 383 amostras de infeções clínicas analisadas foram recebidas pelo Laboratório de Análises Clínicas da FMV-UL ao longo de um período de 8 anos (1999-2006). O teste de susceptibilidade aos antibióticos foi realizado por difusão de disco usando 37 antibióticos. As espécies de estafilococos foram identificadas por amplificação por PCR dos respetivos genes nuc. Os genes mecA e mecC foram pesquisados por PCR. No total, 293 isolados foram resistentes a pelo menos um antibiótico (76,50%), com as maiores frequências de resistência à penicilina e ampicilina (53%). A maior percentagem de resistência a um antibiótico verificou-se em S. pseudintermedius (80,84%), seguido dos S. aureus (75%), estafilococos coagulase-negativo (ECN) (68,18%) e S. schleiferi (63,44%). Globalmente, 132 isolados foram multirresistentes (34,36%) e apenas 23,50% dos isolados foram suscetíveis a todos os antibióticos testados. A resistência aumentou com o tempo, sendo 2004 o ano com maior percentagem de isolados resistentes de estafilococos (85%). Dez isolados eram resistentes à oxacilina, mas só oito eram mecA positivo (sete ECN e um S. aureus) e nenhum foi positivo para o mecC. Os nossos resultados confirmam a elevada resistência aos antibióticos em estafilococos e ressaltam a importância de uma monitorização contínua dos padrões de resistência para ajustamento da estratégia antimicrobiana.

ABSTRACT - Evolution in antibiotics resistance in Staphylococcus spp. – 1999 a 2006 - The genus Staphylococcus has importance at clinical and economic level, with the emergence of methicillin-resistant and multiresistant strains making it a current issue in Human and Veterinary Medicine. The 383 clinical samples analyzed were received by the Laboratory of Clinical Analysis of the FMV-UL over a period of 8 years (1999-2006). The antimicrobial susceptibility testing was performed by disk diffusion using 37 antibiotics. Staphylococcal species were identified by PCR amplification of the respective nuc gene. The mecA and mecC genes were screened by PCR. In total, 293 isolates were resistant to at least one antibiotic (76,50%), with higher frequencies of resistance to penicillin and ampicillin (53%). The highest resistance to one antibiotic was found in S. pseudintermedius (80,84%) followed by S. aureus (75%), coagulase-negative staphylococci (CNS) (68,18%) and S. schleiferi (63,44%). Overall, 132 isolates were multidrug resistant (34,46%) and only 23,50% of the isolates were susceptible to all the antibiotics tested. Resistance increased over time, with the highest level observed in 2004 (85%). Ten isolates were resistant to oxacilin, but only 8 were mecA-positive (seven CNS and one S. aureus) and none was mecC-positive. Our results confirmed that antimicrobial resistance is very frequent in…

Advisors/Committee Members: Pomba, Maria Constança Matias Ferreira, Félix, Nuno Manuel Mira Flor Santos.

Subjects/Keywords: Staphylococcus; resistências; antibióticos; resistances; antibiotic

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Monchique, C. R. O. (2013). Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006. (Thesis). Technical University of Lisbon. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6229

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):

Monchique, Cláudia Raquel Oliveira. “Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006.” 2013. Thesis, Technical University of Lisbon. Accessed January 16, 2021. http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6229.

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

MLA Handbook (7^th Edition):

Monchique, Cláudia Raquel Oliveira. “Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006.” 2013. Web. 16 Jan 2021.

Vancouver:

Monchique CRO. Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006. [Internet] [Thesis]. Technical University of Lisbon; 2013. [cited 2021 Jan 16]. Available from: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6229.

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

Council of Science Editors:

Monchique CRO. Evolução da resistência aos antibióticos em Staphylococcus spp. : 1999 a 2006. [Thesis]. Technical University of Lisbon; 2013. Available from: http://www.rcaap.pt/detail.jsp?id=oai:www.repository.utl.pt:10400.5/6229

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

Universiteit Utrecht

20. Wekesa, A.N. Prevalence of antibiotic resistance in East African Hospitals.

Degree: 2014, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/297497

► Introduction: Antibiotic resistance is a global burden, besides it is worse in low and middle-income countries where infectious diseases are still on the rise. This… (more)

Subjects/Keywords: Antibiotic resistance; hospitals; East Africa

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Wekesa, A. N. (2014). Prevalence of antibiotic resistance in East African Hospitals. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/297497

Chicago Manual of Style (16^th Edition):

Wekesa, A N. “Prevalence of antibiotic resistance in East African Hospitals.” 2014. Masters Thesis, Universiteit Utrecht. Accessed January 16, 2021. http://dspace.library.uu.nl:8080/handle/1874/297497.

MLA Handbook (7^th Edition):

Wekesa, A N. “Prevalence of antibiotic resistance in East African Hospitals.” 2014. Web. 16 Jan 2021.

Vancouver:

Wekesa AN. Prevalence of antibiotic resistance in East African Hospitals. [Internet] [Masters thesis]. Universiteit Utrecht; 2014. [cited 2021 Jan 16]. Available from: http://dspace.library.uu.nl:8080/handle/1874/297497.

Council of Science Editors:

Wekesa AN. Prevalence of antibiotic resistance in East African Hospitals. [Masters Thesis]. Universiteit Utrecht; 2014. Available from: http://dspace.library.uu.nl:8080/handle/1874/297497

Mississippi State University

21. Arroyo-Llantin, Norman Noriel. Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities.

Degree: PhD, Food Science, Nutrition, and Health Promotion, 2013, Mississippi State University

URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-02092013-101239/ ;

► <i>Salmonella</i> spp. is a human pathogen that has been reported in catfish, but with conflicting results. <i>Salmonella</i> spp. was isolated from live catfish, catfish… (more)

Subjects/Keywords: antibiotic resisatnce; clonal similarities; Salmonella

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Arroyo-Llantin, N. N. (2013). Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-02092013-101239/ ;

Chicago Manual of Style (16^th Edition):

Arroyo-Llantin, Norman Noriel. “Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities.” 2013. Doctoral Dissertation, Mississippi State University. Accessed January 16, 2021. http://sun.library.msstate.edu/ETD-db/theses/available/etd-02092013-101239/ ;.

MLA Handbook (7^th Edition):

Arroyo-Llantin, Norman Noriel. “Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities.” 2013. Web. 16 Jan 2021.

Vancouver:

Arroyo-Llantin NN. Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities. [Internet] [Doctoral dissertation]. Mississippi State University; 2013. [cited 2021 Jan 16]. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-02092013-101239/ ;.

Council of Science Editors:

Arroyo-Llantin NN. Isolation, antibiotic resistance and clonal similarities of Salmonella spp. in catfish and processing facilities. [Doctoral Dissertation]. Mississippi State University; 2013. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-02092013-101239/ ;

McMaster University

22. King, Andrew M. DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS.

Degree: PhD, 2016, McMaster University

URL: http://hdl.handle.net/11375/19497

►

The discovery of antibiotics and their subsequent clinical use has had a tremendous and beneficial impact on human health. The β-lactam antibiotics, which include penicillins,… (more)

▼

The discovery of antibiotics and their subsequent clinical use has had a tremendous and beneficial impact on human health. The β-lactam antibiotics, which include penicillins, cephalosporins, carbapenems, and monobactams, constitute over half of the global antibiotic market. However, like all antibiotics, the β-lactams are susceptible to bacterial antibiotic resistance. One of the most disconcerting manifestations of bacterial resistance to β-lactam antibiotics is the evolution and dissemination of β-lactamases, enzymes able to chemically inactivate β-lactam antibiotics. These resistance determinants are the key contributing factor to extensively-drug resistant Gram-negative pathogens, for which we are already bereft of chemotherapeutic treatment options in some cases. The coadministration of a β-lactamase inhibitor (BLI) with a β-lactam antibiotic is a proven therapeutic strategy to counter β-lactamase expression. Unfortunately, the emergence of both serine β-lactamases (SBLs) that are resistant to BLIs and metallo-β-lactamases (MBLs), which are intrinsically resistant to BLIs due to a discrete mechanism of β-lactam hydrolysis, threaten the efficacy of combination therapy. Notwithstanding this bacterial adaptation, the discovery and development of novel BLIs is an attractive strategy to evade resistance, as evidenced by the recent clinical approval of the diazabicyclooctane (DBO) SBL inhibitor, avibactam. Herein, I describe efforts directed at understanding the mechanism of avibactam SBL inhibition. Furthermore, DBO derivatives are shown to display bifunctional properties in inhibiting both β-lactamases and the targets of β-lactam antibiotics, the penicillin-binding proteins. In addition to understanding the enzymology and chemical biology of DBOs, I describe two screening campaigns directed towards discovering inhibitors of MBLs, an unmet clinical need. Using target and cell-based screening of both synthetic and natural product chemical libraries, a fungal natural product inhibitor of clinically relevant MBLs was discovered and characterized. This study expands our understanding of the mechanisms by which DBOs can be used to combat extensively drug-resistant Gram-negative pathogens. It also describes the discovery of a new natural product MBL inhibitor using a workflow that should be amenable to other resistance determinants. It’s hoped that these studies can contribute meaningfully to countering antibiotic resistance observed in clinical settings.

Thesis

Doctor of Philosophy (PhD)

Beta-lactam antibiotics like penicillin are a mainstay for treatment of bacterial infections. Bacterial resistance to these antibiotics threatens their utility and therefore new strategies are required to counter this phenomenon. Herein I describe efforts aimed at understanding new drugs and candidate drugs that act by inhibiting the function of enzymes produced by bacteria that are able to degrade beta-lactam antibiotics. Through the discovery of new molecules and an understanding of their chemical…

Advisors/Committee Members: Wright, Gerard D., Chemistry and Chemical Biology.

Subjects/Keywords: Chemical Biology; Antibiotic Resistance

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

King, A. M. (2016). DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/19497

Chicago Manual of Style (16^th Edition):

King, Andrew M. “DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS.” 2016. Doctoral Dissertation, McMaster University. Accessed January 16, 2021. http://hdl.handle.net/11375/19497.

MLA Handbook (7^th Edition):

King, Andrew M. “DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS.” 2016. Web. 16 Jan 2021.

Vancouver:

King AM. DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS. [Internet] [Doctoral dissertation]. McMaster University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11375/19497.

Council of Science Editors:

King AM. DISCOVERY AND CHARACTERIZATION OF NOVEL BETA-LACTAMASE INHIBITORS. [Doctoral Dissertation]. McMaster University; 2016. Available from: http://hdl.handle.net/11375/19497

McMaster University

23. Kelso, Jayne. Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae.

Degree: MSc, 2016, McMaster University

URL: http://hdl.handle.net/11375/20423

►

The rifamycins are a class of antibiotics which were once used almost exclusively to treat tuberculosis, but are currently receiving renewed interest. Resistance to rifamycins… (more)

▼

The rifamycins are a class of antibiotics which were once used almost exclusively to treat tuberculosis, but are currently receiving renewed interest. Resistance to rifamycins is most commonly attributed to mutations in the drug target, RNA polymerase. Yet environmental isolates are also able to enzymatically inactivate rifamycins in a number of ways. Recently, rifamycin resistance determinants from the environment were found to be closely associated with a so called rifamycin associated element (RAE). The region containing the RAE from an environmental strain was shown to induce gene expression in the presence of rifamycins, hinting at an inducible system for rifamycin resistance. In this work, we examine the RAE from a model organism for Streptomyces genetics, Streptomyces venezuelae. We confirm that the promoter region containing the RAE upstream of a rifamycin monooxygenase rox is inducible by rifamycins. The strains of S. venezuelae generated in this work can be used in future genetic studies on the RAE. As well, the rifamycin monooxygenase Rox was purified for the first time and characterized biochemically. The structure of Rox was obtained with and without the substrate rifampin. Steady state kinetics for the enzyme were determined with a number of substrates, and its ability to confer resistance to rifamycins was examined. Monooxygenated rifamycin SV compound was purified and structurally characterized by NMR analysis. We proposed an aromatic hydroxylase type mechanism for Rox, in which the enzyme hydroxylates the aromatic core of the rifamycin scaffold and causes a non-enzymatic C-N bond cleavage of the macrolactam ring. This is a new mechanism of rifamycin resistance, and sheds some light on the decomposition of rifamycins mediated by monooxygenation, which is still poorly understood.

Thesis

Master of Science (MSc)

Antibiotic resistance represents a major threat to global health. Infections that were once readily treatable are no longer so due to the rise in multidrug resistant bacteria. As our arsenal of effective antibiotics is depleted, new drugs are being discovered less and less frequently. This has caused the scientific community to get creative in coming up with treatments: trying combinations of antibiotics, using antibiotics which were once considered too toxic, and repurposing antibiotics for different bacteria. Rifamycins are a class of antibiotics most commonly used in the treatment of tuberculosis. However, they are becoming more widely used as a result of antibiotic resistance. There are a number of different ways bacteria can become resistant to the harmful effects of rifamycins: by modifying the target so the drug can no longer bind to it, actively pumping the drug out of the cell, or by changing the drug in some way so it is no longer effective. Bacteria in the environment use antibiotics as a form of chemical warfare to gain an advantage over their neighbours; therefore, they have had millions of years to evolve very effective methods of antibiotic resistance. By surveying…

Advisors/Committee Members: Wright, Gerard D, Biochemistry and Biomedical Sciences.

Subjects/Keywords: Antibiotic resistance; Enzymology; Rifamycins

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Kelso, J. (2016). Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/20423

Chicago Manual of Style (16^th Edition):

Kelso, Jayne. “Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae.” 2016. Masters Thesis, McMaster University. Accessed January 16, 2021. http://hdl.handle.net/11375/20423.

MLA Handbook (7^th Edition):

Kelso, Jayne. “Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae.” 2016. Web. 16 Jan 2021.

Vancouver:

Kelso J. Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae. [Internet] [Masters thesis]. McMaster University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11375/20423.

Council of Science Editors:

Kelso J. Characterizing the mechanism and regulation of a rifamycin monooxygenase in Streptomyces venezuelae. [Masters Thesis]. McMaster University; 2016. Available from: http://hdl.handle.net/11375/20423

24. Pawlowski, Andrew. Diversity and Evolution of Antibiotic Resistomes.

Degree: PhD, 2017, McMaster University

URL: http://hdl.handle.net/11375/22808

►

The relentless evolution of antibiotic resistance in pathogens is one of the most pressing medical concerns of the 21st century. Antibiotic resistance and antibiotic drugs… (more)

▼

The relentless evolution of antibiotic resistance in pathogens is one of the most pressing medical concerns of the 21st century. Antibiotic resistance and antibiotic drugs originated in environmental bacteria, where they have been integral to their evolution for millions of years. The application of antibiotics in medicine and agriculture has selected for mobilization and dissemination of resistance genes in pathogens. Understanding their evolution here will aid in combating their evolution in pathogens. This work expands the known mechanistic, functional, and genetic diversity of resistance (i.e. resistomes) in environmental bacteria. I systematically parse the extensively drug-resistant resistome of Paenibacillus sp. LC231, which was sampled from an underground ecosystem spatiotemporally isolated from the surface for over 4 Myr. Paenibacillus sp. LC231 was resistant to 26 of 40 drugs tested. Informatic annotation of resistance genes and functional genomes revealed 18 new resistance elements including five determinants without characterized homologs and three mechanisms not previously known to confer resistance. I investigated the resistome of Brevibacillus brevis VM4 to study the relationship between species diversity and resistance diversity in the Paenibacillaceae family, which includes Paenibacillus sp. LC231. I found that resistome diversity does not correlate with species diversity, consistent with horizontal transfer of resistance genes. In each of Paenibacillus sp. LC231 (MphI) and B. brevis VM4 (MphJ), I identified Mphs with unique substrate specifies. I identified the molecular determinants of substrate discrimination in MphI and in doing so, I developed a general strategy for understanding and predicting the functional evolution of resistance enzymes. Together, this work expands the known diversity of resistance that will enable better detection of resistance in pathogens.

Thesis

Doctor of Philosophy (PhD)

Infections caused by antibiotic resistant bacteria are a significant medical problem. Bacteria will always become resistant to antibiotic drugs. Understanding how resistance evolves is essential for increasing the effective lifetime of these drugs. Antibiotics have been naturally produced by bacteria for millions of years, which caused the spread of resistance in environmental bacteria. Medical and agricultural antibiotic use by humans caused resistance in environmental bacteria to transfer to pathogenic bacteria. My work expands the known causes of resistance in environmental bacteria so that we can better detect the causes of resistance in pathogens. In doing so, I demonstrate that multi-drug resistance is over 4 million years old and that environmental bacteria naturally transfer resistance genes. Furthermore, I develop a way to predict the evolution of new resistance functions by inferring their evolutionary histories.

Advisors/Committee Members: Wright, Gerard, Biochemistry and Biomedical Sciences.

Subjects/Keywords: Antibiotics; Antibiotic resistance; Microbial evolution

10 more images…

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Pawlowski, A. (2017). Diversity and Evolution of Antibiotic Resistomes. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/22808

Chicago Manual of Style (16^th Edition):

Pawlowski, Andrew. “Diversity and Evolution of Antibiotic Resistomes.” 2017. Doctoral Dissertation, McMaster University. Accessed January 16, 2021. http://hdl.handle.net/11375/22808.

MLA Handbook (7^th Edition):

Pawlowski, Andrew. “Diversity and Evolution of Antibiotic Resistomes.” 2017. Web. 16 Jan 2021.

Vancouver:

Pawlowski A. Diversity and Evolution of Antibiotic Resistomes. [Internet] [Doctoral dissertation]. McMaster University; 2017. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11375/22808.

Council of Science Editors:

Pawlowski A. Diversity and Evolution of Antibiotic Resistomes. [Doctoral Dissertation]. McMaster University; 2017. Available from: http://hdl.handle.net/11375/22808

Penn State University

25. Harrow, Danielle Irene. Greywater Reuse: Impact of Triclosan on Soil Microorganisms.

Degree: 2012, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/13928

► The use of greywater for irrigation results in the direct discharge of trace quantities of personal care products and antimicrobial agents to the environment. The… (more)

▼ The use of greywater for irrigation results in the direct discharge of trace quantities of personal care products and antimicrobial agents to the environment. The presence of antibacterial compounds (e.g. triclosan) in greywater raises concerns regarding potential impacts of these materials on the environment and human health. Our research examined the impact of triclosan on soil microbial communities using soil filled pots irrigated with greywater (synthetic) only or greywater with triclosan. Functional diversity of the heterotrophic microbial community was assayed. Soil samples were cultured for viable heterotrophic bacteria and triclosan-resistant heterotrophic bacteria in the two treatments. Isolates were evaluated for resistance to multiple antibiotics and used to quantify tetracycline resistance genes. Under constant exposure, the community structure, showed two very distinct heterotrophic assemblages between soils treated with triclosan and the control soil. There were statistically significant increases in the number of heterotrophic organisms resistant to triclosan when the two soils were compared. The frequency of the tet a gene increased significantly in subsamples irrigated with greywater with triclosan as well as the proportion of bacterial isolates resistant to multiple antibiotics in these soil samples. Our results indicate that triclosan in greywater can have significant impacts on soil microbes. This in turn can affect the types of available nutrients within the soil. While antibacterial products may be present in trace concentrations in greywater, repeated exposure to soil organisms may be selecting for bacteria resistant to multiple types of antibiotics. Therefore, our results indicate that greywater should be treated to remove antibacterial agents before its use in lawn irrigation. Alternatively, the use of antibacterial containing products should be significantly reduced. Advisors/Committee Members: Katherine H Baker, Thesis Advisor/Co-Advisor, Yen Chih Chen, Thesis Advisor/Co-Advisor, Shirley Elizabeth Clark, Thesis Advisor/Co-Advisor.

Subjects/Keywords: Triclosan; Antibiotic Resistance; Greywater

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Harrow, D. I. (2012). Greywater Reuse: Impact of Triclosan on Soil Microorganisms. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/13928

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):

Harrow, Danielle Irene. “Greywater Reuse: Impact of Triclosan on Soil Microorganisms.” 2012. Thesis, Penn State University. Accessed January 16, 2021. https://submit-etda.libraries.psu.edu/catalog/13928.

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

MLA Handbook (7^th Edition):

Harrow, Danielle Irene. “Greywater Reuse: Impact of Triclosan on Soil Microorganisms.” 2012. Web. 16 Jan 2021.

Vancouver:

Harrow DI. Greywater Reuse: Impact of Triclosan on Soil Microorganisms. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Jan 16]. Available from: https://submit-etda.libraries.psu.edu/catalog/13928.

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

Council of Science Editors:

Harrow DI. Greywater Reuse: Impact of Triclosan on Soil Microorganisms. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/13928

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

Penn State University

26. Gumkowski, James. Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors.

Degree: 2020, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/17593jdg298

► Radical S-adenosylmethionine (SAM) enzymes are one of the largest protein superfamilies identified to date, with more than 500,000 annotated members. While the functions of these… (more)

▼ Radical S-adenosylmethionine (SAM) enzymes are one of the largest protein superfamilies identified to date, with more than 500,000 annotated members. While the functions of these enzymes vary widely, one of the most challenging chemical transformations that radical SAM enzymes are known to perform is methylation of unactivated carbon or phosphorous centers. The enzymes that catalyze these difficult reactions are known as the Class A-D radical SAM methyltransferases. The best characterized of the radical SAM methyltransferases are Class A, composed of RlmN and Cfr. RlmN is a housekeeping enzyme found in many bacteria that methylates rRNA and some tRNAs and is thought to promote translational fidelity. In contrast, Cfr is found in relatively few bacteria, largely Firmicutes, and its modification of rRNA has been shown to confer antibiotic resistance to agents which target the exit tunnel of the peptidyl transferase center. It accomplishes this by appending a methyl group to the C8 position of A2503 (Escherichia coli numbering). cfr is of particular concern presently because it has been found on transposable elements and is appearing with increasing frequency in clinical settings. The original aim of this work was to structurally characterize a member of the Cfr family, a goal which required finding sequences which diverge from model system Staphylococcus aureus Cfr. In chapter 2, four phylogenetically diverse Cfr homologs were isolated and characterized. Though none proved amenable to structural studies, biophysical and spectroscopic analyses revealed that all four homologs contained the radical SAM [4Fe-4S] cluster and were able to perform C8 methylation of a 155mer substrate mimic with varying efficiencies. These results suggest that Cfr-like activity associated with drug resistance can be found in a diverse set of organisms, some of which are human pathogens. I also showed that the identity of the iron-sulfur cluster reductant can have a significant impact on activity. The small molecule reductant dithionite yielded more dimethylated product compared to a flavodoxin protein-based reducing system. This work underscores the importance of studying Cfr activity with native reductants, because reaction outcome can be influenced by the identity of the reducing system and the rate at which it operates relative to RNA product release. In this dissertation I show that a clostridial Cfr homolog is an active rRNA methylase in vitro, a surprising observation given the lack of activity in other homologs from the clostridial clade. Additionally, the Mössbauer spectrum of Clostridioides difficile Cfr demonstrated the presence of a mononuclear iron cofactor in the C-terminal domain. In chapter 3, I use truncation variants to verify the biophysical and functional properties of this domain. When isolated separately, the domain binds a single iron (II) ion with rubredoxin-like properties. Addition of this domain in trans to a clostridial Cfr variant containing only the radical SAM domain did not affect activity. However,… Advisors/Committee Members: Amie Kathleen Boal, Dissertation Advisor/Co-Advisor, Amie Kathleen Boal, Committee Chair/Co-Chair, Squire J Booker, Committee Member, Carsten Krebs, Committee Member, Ken Keiler, Outside Member, Philip C Bevilacqua, Program Head/Chair.

Subjects/Keywords: Antibiotic resistance; Cfr; KTR

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Gumkowski, J. (2020). Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17593jdg298

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):

Gumkowski, James. “Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors.” 2020. Thesis, Penn State University. Accessed January 16, 2021. https://submit-etda.libraries.psu.edu/catalog/17593jdg298.

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

MLA Handbook (7^th Edition):

Gumkowski, James. “Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors.” 2020. Web. 16 Jan 2021.

Vancouver:

Gumkowski J. Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors. [Internet] [Thesis]. Penn State University; 2020. [cited 2021 Jan 16]. Available from: https://submit-etda.libraries.psu.edu/catalog/17593jdg298.

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

Council of Science Editors:

Gumkowski J. Biochemical Characterization of Phylogenetically Diverse Homologs of the Antibiotic Resistance Protein Cfr and Related Genome Neighbors. [Thesis]. Penn State University; 2020. Available from: https://submit-etda.libraries.psu.edu/catalog/17593jdg298

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

Texas A&M University

27. Spittle, Leah S. Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners.

Degree: MS, Education for Healthcare Professionals, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/157735

► Antibiotic prophylaxis, administered prior to dental treatment, has been important in the prevention of infective endocarditis. The American Heart Association (AHA) and the American Academy… (more)

▼ Antibiotic prophylaxis, administered prior to dental treatment, has been important in the prevention of infective endocarditis. The American Heart Association (AHA) and the American Academy of Orthopaedic Surgeons (AAOS) have developed guidelines for the use of antibiotic prophylaxis in healthcare and dentistry. However, various changes in the antibiotic prophylaxis guidelines in recent years have caused confusion for many healthcare providers, dentists, and patients. Currently, there is limited research on United States dental practitioner’s prescribing practices of antibiotic prophylaxis. The purpose of this study was to examine whether dental practitioners in Texas, Oklahoma, and Kansas were following the 2007 guidelines of the AHA and AAOS regarding the use of antibiotic prophylaxis. A questionnaire was sent to 600 dentists in varying areas of dental practice with a response rate of 28.7% (n=172). Data analysis was performed using descriptive statistics, weighted logistic regression, and quadratic polynomial regression analysis. In addition, a scoring system was created to analyze dentists’ antibiotic prophylaxis prescribing practices for specific survey questions. This study found that 56% (n=97) of the respondents were following the current 2007 AHA antibiotic prophylaxis guidelines. Results of this study also revealed that 71.7% (n=119) of respondents prescribed antibiotic prophylaxis within the first two years after total prosthetic joint replacement, while 57.8% (n=96) continued to prescribe antibiotic prophylaxis beyond two years. The respondents of this study were asked if the patient was an integral part of the decision making process when discussing an antibiotic prophylaxis regimen. The majority of respondents (72.4%, n=123) stated that the patient was included in the decision to take antibiotic prophylaxis if needed. In regard to antibiotic resistance, the majority of respondents (73.2%, n=120) stated they believed there is a risk for antibiotic resistance if a patient is taking the required antibiotic prophylaxis regimen for each dental visit. Approximately 92% (n=155) of respondents believed there was confusion regarding antibiotic prophylaxis protocols used in dentistry, specifically including data suggesting that dentists and physicians do not agree on which conditions should be covered prophylactically. Future studies need to include a larger sample size to determine compliance with antibiotic prophylactic guidelines. Advisors/Committee Members: Muzzin, Kathleen (advisor), Campbell, Patricia (committee member), DeWald, Janice (committee member), Rivera-Hidalgo, Francisco (committee member).

Subjects/Keywords: Antibiotic Prophylaxis; Dentistry; Dental Hygiene

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Spittle, L. S. (2016). Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157735

Chicago Manual of Style (16^th Edition):

Spittle, Leah S. “Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners.” 2016. Masters Thesis, Texas A&M University. Accessed January 16, 2021. http://hdl.handle.net/1969.1/157735.

MLA Handbook (7^th Edition):

Spittle, Leah S. “Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners.” 2016. Web. 16 Jan 2021.

Vancouver:

Spittle LS. Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/1969.1/157735.

Council of Science Editors:

Spittle LS. Current Prescribing Practices for Antibiotic Prophylaxis: A Survey of Dental Practitioners. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/157735

McMaster University

28. Johnson, Emma. SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS.

Degree: MSc, 2019, McMaster University

URL: http://hdl.handle.net/11375/25080

►

Abstract The current rise in antibiotic resistance and lack of discovery of new antibiotics in recent years has caused an antibiotic crisis. A strategy for… (more)

Subjects/Keywords: edeine; organic chemistry; synthesis; antibiotic

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Johnson, E. (2019). SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/25080

Chicago Manual of Style (16^th Edition):

Johnson, Emma. “SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS.” 2019. Masters Thesis, McMaster University. Accessed January 16, 2021. http://hdl.handle.net/11375/25080.

MLA Handbook (7^th Edition):

Johnson, Emma. “SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS.” 2019. Web. 16 Jan 2021.

Vancouver:

Johnson E. SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS. [Internet] [Masters thesis]. McMaster University; 2019. [cited 2021 Jan 16]. Available from: http://hdl.handle.net/11375/25080.

Council of Science Editors:

Johnson E. SYNTHESIS OF EDEINE DERIVATIVES AS AN APPROACH TO TACKLE THE ANTIBIOTIC CRISIS. [Masters Thesis]. McMaster University; 2019. Available from: http://hdl.handle.net/11375/25080

Penn State University

29. Foley, Caitlin Ann. Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance.

Degree: 2014, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/21552

► Antibiotic drugs have been used to combat pathogenic bacteria for over fifty years and have proven to be one of the most valuable tools in… (more)

▼ Antibiotic drugs have been used to combat pathogenic bacteria for over fifty years and have proven to be one of the most valuable tools in preserving human and animal health. With an increase in the use and availability of antibiotics, antibiotic resistance has become a public health concern and has received much attention from government agencies, public interest groups, and the media. There is disagreement within the medical, veterinary, and regulatory communities regarding the veterinary use of antibiotics and associated risks to public health, and it is therefore important to investigate the many facets of antibiotic use and encourage the development of educational programs and resources for all stakeholders. This study focused on the use of a conceptual framework and survey instruments to explore the beliefs, knowledge and practices of veterinarians and to assess the current status of available educational resources pertaining to antibiotic use and antibiotic resistance. The primary purpose of this study was to investigate a wide variety of Pennsylvania veterinarians in order to identify relationships and differences between their perspectives, and facilitate the development of educational programs and strategies to benefit the field of veterinary medicine, animal industry stakeholders, and the public. A non-experimental, descriptive-correlational research design was used to develop this study that focused on the population of all veterinarians licensed to practice medicine in Pennsylvania. Survey instruments were designed to capture the perspectives of two different groups of veterinarians: Group 1 – food/large animal vets, and Group 2 – all other vets. The surveys contained three sections to obtain demographic information, veterinarian perspectives of antibiotic use and antibiotic resistance across five perspectives dimensions (Antibiotic Resistance, Antibiotic Use, Veterinary Clientele, the General Public, and Veterinarian Practices), and perspectives of available educational resources. Veterinarians attending the PVMA Keystone conference completed a total of 66 usable paper surveys, and veterinarians contacted via email listservs completed 284 usable internet-based surveys. Findings indicated that the two groups of veterinarians possessed varied perceptions across the five perspectives dimensions, and that significant differences in perspectives existed (p < .05). Data also indicated that the two groups of veterinarians recommended different types of antibiotic drugs for disease treatment and prevention. Significant relationships existed between the select demographic variables (gender and years post-graduation from veterinary school) and the five perspectives dimensions. Findings also indicated the need for educational materials and resources regarding antibiotic resistance for veterinarians, veterinary staff, veterinary clientele, and the general public; and concluded that veterinarians may be the best resource for educating their staff and clientele. Several modes for disseminating educational… Advisors/Committee Members: Rama B Radhakrishna, Dissertation Advisor/Co-Advisor, Edgar Paul Yoder, Committee Member, John Ewing, Committee Member, Bhushan M Jayarao, Special Member.

Subjects/Keywords: veterinarian; perspectives; antibiotic resistance; livestock

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Foley, C. A. (2014). Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/21552

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):

Foley, Caitlin Ann. “Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance.” 2014. Thesis, Penn State University. Accessed January 16, 2021. https://submit-etda.libraries.psu.edu/catalog/21552.

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

MLA Handbook (7^th Edition):

Foley, Caitlin Ann. “Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance.” 2014. Web. 16 Jan 2021.

Vancouver:

Foley CA. Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance. [Internet] [Thesis]. Penn State University; 2014. [cited 2021 Jan 16]. Available from: https://submit-etda.libraries.psu.edu/catalog/21552.

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

Council of Science Editors:

Foley CA. Pennsylvania veterinarian perspectives of antibiotic use and antibiotic resistance. [Thesis]. Penn State University; 2014. Available from: https://submit-etda.libraries.psu.edu/catalog/21552

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

Addis Ababa University

30. Getnet, Worku. Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa .

Degree: 2012, Addis Ababa University

URL: http://etd.aau.edu.et/dspace/handle/123456789/2931

► Background -Acute infective diarrhoea and gastroenteritis are major causes of ill health and premature death in developing world due, in large part, to the lack… (more)

▼ Background -Acute infective diarrhoea and gastroenteritis are major causes of ill health and premature death in developing world due, in large part, to the lack of safe drinking water, sanitation and hygiene, as well as poorer overall health and nutritional status. Among the leading causes of infectious diarrhoea, Campylobacter and Shigella contribute a lot. Antimicrobial resistance has developed among many of the major diarrheal bacterial pathogens and complicated the selection of antibiotics for the treatment of enteric bacterial pathogens, particularly to commonly used antimicrobial agents such as ampicillin, tetracycline and trimethoprim–sulfamethoxazole. Objective - To isolate and determine antibiotic susceptibility pattern of Shigella, and Campylobacter from acute enteric infections in Addis Ababa Method - A cross sectional study was conducted from December 2010 to March 2011 at Shiromeda health center (n=254) and Yekatit 12 Hospital (n=140). All diarrheal stool specimens were cultured for isolation of Shigella and Campylobacter species. Antimicrobial susceptibility testing was performed for culture isolates according to the method of Clinical and Laboratory Standards Institute (CLSI) by disk diffusion method. Result – A total of 163 enteropathogens were isolated from 394 patients that had acute diarrhea. The isolates were 37 (9.4%) Shigella species, 19 (4.8%) Campylobacter species, 23 (5.8%) Salmonella species and 84 (21.3%) parasites. 192 (48.7%) of the patients were females and 202 (51.3%) were males making the female to male ratio 1:1.05. The antimicrobial susceptibility pattern for 37 strains of Shigella isolates showed 67.6% resistance to ampicillin followed by, trimethoprim-sulfamethoxazole (64.7%), and chloramphenicol (40.5%). More than 90% of the strains were sensitive to nalidixic acid ciprofloxacin, norfloxacin and polymyxin B. Multiple resistances (resistant to two or more drugs) were observed in 23 (62.1%) of the isolates. All Campylobacter spp. were susceptible to chloramphenicol and showed low resistance rates (<60%) against, trimethoprim-sulfamethoxazole, ampicillin, nalidixic acid, ciprofloxacin and erythromycin. Conclusion- the results of the present study showed the high prevalence for Shigella spp. while Campylobacter spp. showed a moderate one. Continuous surveillance of the prevalence and VIII antibiotic susceptibility pattern of diarrheal bacteria in hospitals and in the community is needed which should be the basis for empiric therapy. Advisors/Committee Members: Ato Tamrat Abebe (PhD candidate, Department of Microbiology, Immunology & Parasitology Addis Ababa University ) (advisor).

Subjects/Keywords: Antibiotic Susceptibility; Acute Enteric Infections

Record Details Similar Records Cite « Share

❌

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

APA (6^th Edition):

Getnet, W. (2012). Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa . (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/2931

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):

Getnet, Worku. “Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa .” 2012. Thesis, Addis Ababa University. Accessed January 16, 2021. http://etd.aau.edu.et/dspace/handle/123456789/2931.

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

MLA Handbook (7^th Edition):

Getnet, Worku. “Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa .” 2012. Web. 16 Jan 2021.

Vancouver:

Getnet W. Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa . [Internet] [Thesis]. Addis Ababa University; 2012. [cited 2021 Jan 16]. Available from: http://etd.aau.edu.et/dspace/handle/123456789/2931.

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

Council of Science Editors:

Getnet W. Isolation and Antibiotic Susceptibility of Shigella and Campylobacter from Acute Enteric Infections in Yekatit 12 Hospital and Shiromeda Health center, Addis Ababa . [Thesis]. Addis Ababa University; 2012. Available from: http://etd.aau.edu.et/dspace/handle/123456789/2931

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

		in
And / Or
		in
And / Or
		in
And / Or
		in

Open Access Theses and Dissertations