No presente estudo avaliou-se o potencial de aplicação da bacteriocina 2a produzida pelo Lactobacillus sake 2a em combinação com outras substâncias antimicrobianas na inibição de cepas de Salmonella isoladas de linguiça: S. Derby SD2, S. Enteritidis SE3, S. Hadar SH4, S. Panama SP5 e S. Typhimurium ST6. A partir de cultura de L. sake 2a em caldo MRS, obteve-se por extração ácida e concentração em liofilizador, um extrato protéico de bacteriocina de cerca de 500 UA/ml. Verificou-se que esse extrato protéico de bacteriocina 2a tem atividade contra Listeria monocytogenes Scott A Cmr Emr nos meios de cultura BHI, MRS e TSB com 0,1% de glicose, independente de temperatura e atmosfera de incubação. O extrato protéico de bacteriocina 2a foi utilizado só e em combinação com EDTA, ácido cítrico, ácido lático ou lisozima sobre "pool" de cepas de Salmonella. Todos os antimicrobianos testados apresentaram efeito inibidor contra Salmonella, no entanto, quando combinados à bacteriocina 2a esse efeito foi mais acentuado. Entre os tratamentos realizados, o que apresentou efeito mais potente na eliminação ou inibição de Salmonella foi a combinação bacteriocina 2a mais ácido lático 0,1%. Bacteriocina 2a também se mostrou mais eficiente que a nisina (usada como padrão) em combinações com lisozima e EDTA. O estudo permitiu verificar que existe um bom potencial de uso da bacteriocina 2a ou do L. sake 2a bac+ em alimentos em associação com os antimicrobianos ácido lático, ácido cítrico, EDTA ou lisozima. Entretanto, penas a combinação de antimicrobianos não é suficiente para eliminar ou inibir a multiplicação de Salmonella. As condições de temperatura, concentração e forma de aplicação dos tratamentos combinados podem variar e são pontos importantes quando se visa à ação direta sobre as células do patógeno ou quando este está associado a um substrato. / The objective of this study was to analyse the potential of application of bacteriocin 2a produced by Lactobacillus sake 2a in combination with other antimicrobials substances on inhibition of strains of Salmonella isolated from raw Brazilian sausages (lingüiça): S. Derby SD2, S. Enteritidis SE3, S. Hadar SH4, S. Panama SP5 and S. Typhimurium ST6. Culture of L. sake 2a grown at 30ºC in MRS broth was used to obtain a cell-free supernatant after centrifugation. This cell-free supernatant was submitted to acid extraction method for bacteriocin and water reduction by liofilization process. After this, a final fraction was obtained and denominated proteic extract of bacteriocin 2a and had a final concentration of approximately 500 A.U/mL. Proteic extract of bacteriocin 2a obtained from cultures of L. sake 2a grown in broths: BHI, MRS, and TSB with 0.1% of glucose showed bactericidal effect against Listeria monocytogenes Scott A Cmr Emr, in any condition of temperature and atmosphere. The proteic extract of bacteriocin 2a was used alone and in combination with EDTA, citric acid, lactic acid or lyzozyme on pool of strains of Salmonella. All antimicrobials tested showed inhibitory effect against Salmonella, but in combination to bacteriocin 2a this effect was more efficient on inhibition or elimination of Salmonella. Bacteriocin 2a showed be more efficient than nisin when in association with lyzozyme and EDTA. This study was able to verify that exist a great potential of application of bacteriocin 2a and/or L. sake 2a bac+, in foods in combination with the antimicrobials: lactic acid, citric acid, EDTA or lyzozyme. However, the simple combination of these antimicrobials is not sufficient to eliminate or inhibit the growth of Salmonella. Temperature conditions, concentration of antimicrobials and form of application of treatments can change and they are very important points; mainly when the aim of the study is to evaluate the direct action of antimicrobials on cells of pathogen or action of these substances on pathogen into a specific substrate.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-10-02T14:48:12Z No. of bitstreams: 1 marianasilvalopesneves.pdf: 523366 bytes, checksum: 2c33e978d12652cf1b17217fe3509198 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-10-09T19:44:11Z (GMT) No. of bitstreams: 1 marianasilvalopesneves.pdf: 523366 bytes, checksum: 2c33e978d12652cf1b17217fe3509198 (MD5) / Made available in DSpace on 2017-10-09T19:44:11Z (GMT). No. of bitstreams: 1 marianasilvalopesneves.pdf: 523366 bytes, checksum: 2c33e978d12652cf1b17217fe3509198 (MD5) Previous issue date: 2013-04-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A prata é conhecida por sua atividade antibacteriana e tem se mostrado eficiente como alternativa no contexto da resistência bacteriana a drogas, sobretudo na forma de nanopartículas (AgNPs). Nossos objetivos foram a avaliação da susceptibilidade de bactérias representativas contra AgNPs e pesquisa de efeito sinérgico ou antagônico quando associadas a quitosana (QIT) e antimicrobianos de uso terapêutico humano. Foram utilizadas oito linhagens bacterianas de referência, representativas de: Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, S. epidermides e Enterococcus faecalis. O perfil de susceptibilidade foi determinado através do método de microdiluição em caldo, de acordo com as recomendações do CLSI. A concentração inibitória mínima (CIM90) das AgNPs para as amostras testadas foi de 64μg/mL, enquanto que para a combinação AgNPs-QIT foi de 16μg/mL. Considerando-se atividade antimicrobiana somente da QIT, a CIM90 foi de 16 μg/mL. Entre os antimicrobianos testados (meropenem, amicacina, gentamicina, levofloxacina, rifampicina, sulfametoxazol-trimetropim, tetraciclina, e oxacilina e vancomicina, estes apenas para Gram positivos), apesar de a CIM para cada linhagem bacteriana estar de acordo com os valores determinados pelo CLSI observou-se diminuição significativa para todas as drogas testadas quando combinadas com AgNPs-QIT. De modo geral, para todas as espécies bacterianas avaliadas, a associação de AgNPs com QIT ou drogas antimicrobianas apresentaram grande potencial inibitório que pode estar relacionado a estabilidade das AgNPs associadas ao polímero ou a interação positiva das nanopartículas com os antimicrobianos. O ensaio de Checkerboard foi realizado para estabelecer os efeitos sinérgicos ou antagônicos em cada combinação. A possibilidade da interação das AgNPs e da QIT com antimicrobianos já existentes é altamente relevante e reforça as recomendações da literatura acerca da reformulação de uso de antimicrobianos tradicionais, além da pesquisa de novas drogas e estratégias para sobrepujar o crescente fenômeno da resistência bacteriana aos antimicrobianos. / Silver is known for its antibacterial activity and has been shown to be effective as a potential alternative in the context of bacterial resistance to drugs, particularly in the form of nanoparticles (AgNPs). Our objectives were to evaluate the susceptibility of bacteria against AgNPs and representative survey of synergistic or antagonistic when combined with chitosan (QIT) and antimicrobials for human therapeutic use. A total of eight reference strains were evaluated of Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, S. epidermidis and Enterococcus faecalis. The susceptibility patterns were determined by broth microdilution method, according to the CLSI guidelines. The minimum inhibitory concentration (MIC90) of AgNPS to the samples tested was 64μg/mL, while for the combination AgNPs-QIT was 16μg/mL. Considering only antimicrobial activity of QIT, the MIC90 was 16 mg / mL. Among the antimicrobials (meropenem, amikacin, gentamicin, levofloxacin, rifampicin, sulfamethoxazole- trimethoprim, tetracycline, and vancomycin and oxacillin, these only to Gram positive), while the MIC for each bacterial strain is in accordance to the reference CLSI, significant decrease was observed for all tested drugs when combined with AgNPs-QIT. In general, association of AgNPs with QIT or with antimicrobial drugs showed higher inhibitory potential, which may be related to the stability of the polymer associated AgNPs or positive interaction of nanoparticles with antibiotics. The Checkerboard assay was then performed to establish antagonistic or synergistic effects in each combination. The possibility of interaction of AgNPs and QIT with existing antimicrobials is highly relevant and reinforces the recommendations of the literature on the reformulation of traditional antimicrobial use, as well as research into new drugs and strategies to overcome the growing phenomenon of bacterial resistance to antimicrobials.

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-18T22:31:24Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Carla_Daiane_Lubke_Ucker.pdf: 1869629 bytes, checksum: faefabb4e99813c029587cc3088d97be (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-18T22:44:22Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Carla_Daiane_Lubke_Ucker.pdf: 1869629 bytes, checksum: faefabb4e99813c029587cc3088d97be (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-18T22:44:29Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Carla_Daiane_Lubke_Ucker.pdf: 1869629 bytes, checksum: faefabb4e99813c029587cc3088d97be (MD5) / Made available in DSpace on 2018-05-18T22:44:29Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Carla_Daiane_Lubke_Ucker.pdf: 1869629 bytes, checksum: faefabb4e99813c029587cc3088d97be (MD5) Previous issue date: 2016-10-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Óleos essenciais obtidos de plantas podem apresentar propriedades antimicrobianas e antioxidantes, possibilitando sua utilização em alimentos e medicamentos. O jambolão (Syzygium cumini) e a Melaleuca alternifolia, ambos pertencentes à família Myrtaceae, podem ser utilizados na obtenção de óleo essencial. O forte odor característico e a insolubilidade dos óleos essenciais são fatores limitantes para sua aplicação, devido a isso uma alternativa para ampliar o uso é o processo de desodorização. Dessa forma o objetivo do presente trabalho foi avaliar as características do óleo essencial de jambolão e óleo desodorizado de Melaleuca alternifolia, microencapsular o óleo desodorizado de Melaleuca alternifolia e avaliar suas propriedades. O óleo essencial de jambolão, extraído das sementes, apresentou como principal constituinte o β-cariofileno e não apresentou atividade antioxidante no método DPPH. Os óleos essenciais das folhas e sementes de jambolão apresentaram atividade antimicrobiana frente a Escherichia coli, Staphylococcus aureus, Salmonella Typhimurium, Listeria monocytogenes, Trichoderma spp. e Rizhopus spp. O óleo desodorizado de Melaleuca alternifolia apresentou baixo teor de compostos fenólicos e ausência de terpenos. Entretanto, apresentou atividade antibacteriana frente a Escherichia coli, Staphylococcus aureus, Salmonella Typhimurium, Listeria monocytogenes e ausência de atividade antifúngica. Obteve-se alta eficiência de encapsulação do óleo desodorizado de Melaleuca alternifolia pela técnica de coacervação simples utilizando quitosana e ácido tânico, os resultados foram confirmados pela técnica de Calorimetria Diferencial de Varredura. As micropartículas apresentaram formato irregular, tamanho distinto e inibição frente aos microrganismos avaliados, devido à propriedade antimicrobiana da quitosana, porém sem atividade antioxidante. Não foi observada influência quanto a presença do ácido tânico nas micropartículas. O óleo desodorizado de Melaleuca alternifolia apresenta potencial de aplicação em hambúrguer em função de ter apresentado atividade antimicrobiana in situ frente à Escherichia coli, já os óleos essenciais de jambolão não puderam ser analisados in situ devido ao baixo rendimento. / Essential oils obtained from plants may have antimicrobial and antioxidant properties, allowing its use in food and medicine. The jambolan (Syzygium cumini) and Melaleuca alternifolia, both belonging to the Myrtaceae family can be used to obtain an essential oil. The strong characteristic odor and the insolubility of the essential oils are limiting factors for its use due to it an alternative to extend the use is the deodorization process. Thus the objective of this study was to evaluate the essential oil characteristics jambolan and deodorized oil Melaleuca alternifolia, microencapsulating the deodorized oil Melaleuca alternifolia and evaluate their properties. The essential oil jambolan, extracted from the seeds, presented as the main constituent the β-caryophyllene and did not show antioxidant activity in the DPPH method. Essential oils from the leaves and seeds jambolan showed antimicrobial activity against Escherichia coli, Staphylococcus aureus, Salmonella Typhimurium, Listeria monocytogenes, Trichoderma spp. and Rizhopus spp. The deodorized oil Melaleuca alternifolia showed low content of phenolic compounds and absence of terpenes. However, the oil showed antibacterial activity and no antifungal activity. It was obtained high encapsulation efficiency of deodorized oil Melaleuca alternifolia by simple coacervation technique using chitosan and tannic acid, the results were confirmed by Calorimetry Differential Scanning technique. The microparticles presented irregular size and distinctive shape. The microparticles showed potent inhibition compared to the microorganisms evaluated due to the antimicrobial property of chitosan, but no antioxidant activity. No significant differences were observed for the presence of tannic acid in the microparticles. The deodorized oil Melaleuca alternifolia has potential application in burger due to present antimicrobial activity against the Escherichia coli.

Les bactéries Gram-négatif possèdent une structure d'enveloppe, ainsi que des pompes d'efflux (i.e., systèmes de transport actif permettant de détoxifier la cellule bactérienne) qui les rendent naturellement résistantes aux antibiotiques. Ces deux caractéristiques constituent de véritables barrières qui s'opposent à l'accumulation d'une grande variété d'antibiotiques près de leur cible, à l'intérieur de la bactérie. La perturbation des mécanismes s’opposant à l’accumulation d’antibiotiques par des agents chimiosensibilisants représente une stratégie prometteuse.L’objectif de cette thèse était de mieux comprendre les mécanismes d'inhibition de la résistance qui s’oppose à l’accumulation d’antibiotiques chez les bactéries Gram- négatif.Dans un premier temps l'activité de divers agents chimiosensibilisants synthétiques a été caractérisée. Trois dérivés ont été identifiés pour augmenter significativement l'activité synergique avec les antibiotiques, préalablement observée avec le géraniol. Ces dérivés ont montré une activité inhibitrice des pompes d'efflux ou perméabilisatrice de la membrane externe, pouvant être à l'origine des synergies observées.Dans un second temps, une méthode de criblage a été mise au point, en permettant la détection spécifique des agents chimiosensibilisants tout en décrivant leur mécanisme d'action.Ces travaux de thèse ont participé à proposer une solution thérapeutique brevetée au stade pré-clinique. Ils ont en outre permis de mettre en place des outils originaux pour identifier de nouveaux chimiosensibilisants, mais aussi pour mieux comprendre comment perturber les barrières s'opposant à l'accumulation d'antibiotiques. / Gram-negative bacteria are naturally resistant to many classes of antibiotics thanks to their ability to control the accumulation of drugs. Decreasing membrane barrier permeability and producing efflux pumps that expel drugs outside bacteria, represent the prevalent mechanisms of this resistance. One of the most promising solutions consists in restoring antibiotic activity by targeting such barriers to accumulation, with chemosensitizers.The purpose of my PhD was to better understand the inhibition of resistance that opposes the accumulation of antibiotics in Gram-negative bacteria.In the first stage of the study, the activity of various synthetic chemosensitizers has been characterized. Three compounds were identified to significantly increase the synergistic activity with antibiotics, that was previously observed with geraniol. These derivatives showed an efflux pump inhibition or an outer membrane permeabilization effect, that could be related to the observed synergy.In the second stage of the study, a screening method has been developed for the specific detection of chemosensitizers, while describing their mechanism of action.This work participated in proposing a patented therapeutic solution in the preclinical stage. This study has led to new tools to identify novel chemosensitizers, but also to better understand how to impair the barriers opposing the accumulation of antibiotics.

The prevalence of oral diseases such as dental caries and periodontitis and the universal need for effective control of oral health has stimulated a great deal of interest in oral hygienic formulations both scientifically and commercially driven. Such formulations are normally deployed as complex formulations commonly containing antimicrobial actives together with excipients, where both classes of ingredients may contribute to the bacteriological effect of the oral hygienic product. However, the mode of action and/or the bacteriological and microecological effects of exposure of microorganisms to oral hygiene products are poorly understood. In this context, this doctoral dissertation represents a series of investigations to contribute to knowledge in the area. The impact of selected oral antimicrobial actives (triclosan, sodium lauryl sulphate, stannous fluoride and zinc lactate) on a key aspect of bacterial cellular membrane function was investigated. This involved measuring major cellular respiratory pathways during exposure to the test agents using two types of tetrazolium dyes possessing different redox potentials as respiration pathway indicators. Spectrophotometric analyses indicated that sub-lethal levels of triclosan and sodium lauryl sulphate act as uncoupling agents, an observation not previously been reported. Sub-lethal concentrations of stannous fluoride and zinc lactate however, blocked cellular respiration with resulting shifts towards glycolytic/fermentative pathways. The contribution of a variety of test agents to the overall antimicrobial effect of a complex formulation (Listerine®) was investigated in order to understand the relative efficacy of the actives. This was achieved by testing the essential oils present in the formulation singly and in combination utilising in vitro models. The use of the hydroxyapatite disc model (HDM) to grow salivary microcosms to test the efficacy of the ingredients revealed hitherto unreported synergistic activity between the active ingredients thymol and menthol. Proprietary dentifrices (Colgate Total® and Crest ProHealth®) containing the antimicrobial agents triclosan or stannous fluoride/zinc lactate, respectively, were comparatively evaluated. This was performed by simultaneously establishing salivary microcosms in Sorbarod Biofilm Devices (SBDs). Following the establishment of dynamic steady-states, paired devices were dosed with each of the two proprietary dentifrices. Bacteriological data generated after multiple dosing indicated that both dentifrices were comparably effective in the reduction of all tested bacterial functional groups in the plaque models. However, data generated using HDM models indicated greater reductions in Gram-negative anaerobes after exposure to Colgate total®. The observations presented in this thesis may contribute to the development of oral formulations with optimised antimicrobial efficacies against adventitious pathogens present in the oral cavity and help in reducing the incidence of oral diseases and potentially related systemic interface.

Magister Public Health - MPH / Background: The irrational use of medicines, and increasingly antimicrobials, remains a key health problem in many developing countries including Zambia. Inappropriate, ineffective and inefficient use of medicines is common in health facilities at all levels. There are many factors influencing irrational prescribing and dispensing of antimicrobials including patients, prescribers, dispensers, the supply system (including industry influences), government regulations and medicines information and misinformation. Study aim: The aim of the study was to assess the rational use and availability of antimicrobials at primary level health facilities under the Lusaka district community health office, Zambia. Study design: The study was a cross-sectional descriptive study, with prospective and retrospective components. A standardized research methodology, including tools and indicators, adapted from the World Health Organization, was employed. Study population and sampling: The study population included all the 30 government primary level health facilities (health centres) in Lusaka District, from which 20 primary health facilities were sampled using a combination of purposive and random sampling. Using the WHO standard indicators of rational drug use, this study assessed 800 patient encounters, 520 medicines inventory records, and other baseline data, from 20 health facilities at three different levels under the Lusaka district community health office, Zambia. Data collection: The data collection tools were numbered and labeled. Tool 1: Prescribing Indicator Form was used to collect prescribing data; Tool 2: Patient Care (Pharmacy) Form was used to record dispensing data; Tool 3: Antimicrobial Availability Form for recording data for the availability of the key indicator antimicrobials and their substitutes; Tool 4: Facility Indicator Consolidation Reporting Form was used for consolidating the data collected for each health facility under study; and Tool 5: Facility Medicines Use Indicator Consolidation Form was used for the consolidation of the drug use data for the entire study. Third year Pharmacy Technology students were trained for the data collection process. The patients were first observed from outside the prescriber's room and the dispensing area for consultation and dispensing times respectively, and then they were interviewed to collect the prescribing and dispensing data. The tools were pre-tested. Data analysis: After data checking and consolidation, quantitative data were categorized into continuous numerical variables. Calculations were done manually and using computerized analysis (Epi Info package) and presented as simple frequency and means. Ethics: Ethical clearance for the study was obtained from University of the Western Cape Senate Research Committee. Permission was obtained from the Lusaka Provincial and District health offices, being the authorities that are overseeing the health facilities included in the study. Furthermore, permission was obtained from the health centre in-charges. Consent was obtained from healthcare providers and patients. Key results and discussion: The study found that at the primary level facilities there were more Clinical Officers (55%) than Medical Doctors (25%) and Registered Nurses (20%) in charge of prescribing. The main dispensers were Pharmacy Technologists (85%); there were no Pharmacists available in any of the facilities. A third [259 (32.4 %)] of all the 800 patients in the study were children below 12 years of age. Across the clinics, a mean of 2.94 medicines were prescribed per prescription, with an extremely low rate of prescribing drugs by generic name (36.7%). The proportion of prescriptions including an antibiotic was 36.2 % and 3.4 % included an injectable drug. Linking the antimicrobials and injections to patient diagnoses indicated that many were probably irrational, prescribing decisions. Amoxicillin and metronidazole were by far the most commonly prescribed antimicrobials at 32.0 % and 17.2 % of total antimicrobials, respectively. The essential drugs list was available in 80.0% of facilities and a high percentage of medicines were prescribed from the essential medicines list (81.2%). The overall mean percentage of medicines packages correctly labeled was considerably low at 44.8 %. The average consultation time was short at 4.0 (range 1-8.4) minutes, whereas the dispensing times were equally short and averaged at 116.6 (range 15-360) seconds, with the range of 15 to 360 seconds. The average percentage of first line antimicrobials available at health facilities was 79 %; and the average percentage of second line, substitute, antimicrobials available was 15 %. Conclusion: In line with studies from other settings, this medicines use study found considerable overuse and irrational use of antimicrobials in the primary health care clinics in Lusaka District. Irrational medicine prescribing was common and poor dispensing practices were also seen, resulting in poor use of and adherence to medicines and, consequently, poor therapeutic outcomes. Recommendations: Several recommendations have been formulated. They include: Reinforcing the Drug Therapeutic Committees (DTCs) at the national and the local facility level to help manage medicines use; clarification of prescribers and dispensers roles and responsibilities; development, enforcement or adaption of standard operating procedures (SOPS) for prescribing and dispensing; and improvement of prescribing and dispensing practices through introduction of appropriate education, supervision and audit.

Background: The use of antimicrobials has been presented as a significant risk factor for Clostridium difficile infection (CDI). Nevertheless, it remains unclear which antimicrobials are more likely to be associated with CDI. It is mandatory for acute trusts to report the numbers of diagnosed CDI cases to the Health Protection Agency (HPA). There is no national system to collect and analyse antimicrobial usage data from the trusts. The company IMS collects antimicrobial usage data from the trusts for creating marketing research statistics. Therefore, it was hypothesised that data collected from the HPA and from IMS could be used to undertake an ecological study about the association between CDI cases and antimicrobial use in English trusts. Methods: A trust-level Antimicrobial Usage Database provided by IMS and a database, including the numbers of CDI cases for patients aged 65 years old and above, provided by the HPA, were utilised in this work. These referred to 26 out of the 29 NW SHA trusts (that managed 64 hospitals) for the quarters between 2005 and 2008 inclusive. A sample of antimicrobial usage data collected directly from trusts was used to investigate potential limitations in using the Antimicrobial Usage Database for the purpose of this work. Multilevel models were used to study antimicrobial usage and the number of CDI cases over time. These models were also used to investigate the association between the CDI cases and antimicrobial usage in the trusts. The trends of trust antimicrobial usage over time were compared with DH recommendations for the prevention of CDI through antimicrobial prescribing published in 1994, 2005 and 2008. Results: Discrepancies between the antimicrobial usage recorded in the IMS database and in a sample of antimicrobial usage data collected from trusts were found for 31 out of 155 antimicrobial usage records; only 1 of these referred to an antimicrobial with high usage. Eight out of the 23 antimicrobial groups and 10 out of 63 antimicrobials were presented as having high usage. The antimicrobial usage over time increased significantly for 7 antimicrobial groups, decreased significantly for 2 groups and remained constant for 54 groups. The number of CDI cases reported for patients aged 65 years old and above decreased significantly over the time. Trust antimicrobial usage over time changed in the opposite direction compared to the DH recommendations published in 1994, 2004 and 2008, respectively, for 2 out of 11, 3 out of 12 and 3 out of 14 antimicrobial groups/antimicrobials. The increased usage of 5 antimicrobial groups was significantly associated with an increase in the number of CDI cases and an increased usage of 4 antimicrobial groups was significantly associated with a decreased number of CDI cases. Within the antimicrobial groups that were significantly associated with an increased number of CDI cases, the usage of 8 individual antimicrobials was significantly associated with the CDI cases. Discussion/Conclusion: Collecting antimicrobial usage over time for large groups of trusts is very time consuming and requires extensive data manipulation. The similarity of the results of this study with those of previously published studies suggest that HPA and IMS data may be used to investigate the association between CDI cases and antimicrobial usage in English trusts.

The purpose of this research is to support the California Department of Food & Agriculture (CDFA) with education and outreach about recent changes regarding antimicrobial use in livestock, and to enhance their emergency communications network. This was done by characterizing a population of small-scale livestock owners underserved with regards to educational outreach about animal health issues, such as antimicrobial use rules. The project also seeks to enhance public understanding of the importance of responsible antimicrobial use in animal and human health. To accomplish this, the study used a survey administered in person at local farm supply stores and online to investigate the level of understanding of antimicrobial rules among livestock owners in San Luis Obispo county. The survey gathered information about the livestock owners’ practices, connection to livestock groups, and access to information pertaining to animal health among other things. The results of the survey showed that respondents were largely unaware of new rules pertaining to use of antimicrobials in livestock. Familiarity with California rules of this kind was used as an indicator of access to information about animal health and was found to correlate positively with knowledge about antimicrobial resistance and familiarity with federal rules concerning antimicrobial use in livestock. As predicted, respondents with a connection to 4-H and FFA had greater familiarity with both federal and state rules concerning antimicrobial use in livestock.

<p><b>Part I: Design of a Photolabile Backbone Amide Linker for the Synthesis of C-terminally Modified Peptides</b></p> <p>A new photolabile backbone amide linker has been developed for the on-resin synthesis of cyclic and C-terminally modified peptides. The linker (Hcnb) is stable to strongly acidic conditions and instead releases the completed peptide through photolytic cleavage at 365 nm. Hcnb possesses four degrees of orthogonality and is amenable to the preparation of cyclic peptides, C-terminally modified peptides, and fully protected peptides due to its photolabile backbone amide linkage. The Hcnb precursor can be conveniently synthesized in 4 steps from commercially available 4-methyl-3,5-dinitrobenzoic acid. The C-terminal amino acid residue is loaded via reductive amination of the precursor followed by an O→N transacylation for the addition of the second residue in quantitative yields, even when employing sterically bulky residues. Standard Fmoc- or Boc-based synthesis can then be utilized to complete the desired peptide. Hcnb has been used to demonstrate the linear synthesis and subsequent on-resin cyclization of various cyclic peptides of interest, as well as synthesis of C-terminal thioesters on-resin. </p> <p><b>Part II: Development of II-HMG CoA Reductase Inhibitors for use as Gram-Positive Selective Antimicrobials. </b></p> <p>Bacterial resistance to antibiotic drugs is an issue that humans have faced since the first use of sulfa drugs in the 1930s. In recent years, the rate of production of new antimicrobial drugs has diminished, as they are no longer financially beneficial to pharmaceutical companies due to short term use and rapid resistance development. This places the burden of the development of new antimicrobial drug on the academic research field. In the work presented here, progress has been made toward the development of a novel class of antimicrobial compounds. These small molecule inhibitors target II-HMG CoA Reductase, a key enzyme involved in cell wall synthesis in gram-positive bacteria. Based on analysis of co-crystal structures obtained from first- and second- generation inhibitors, structural alterations were made to design a new generation of compounds. Efforts have also been made toward identification of a potential secondary target of these inhibitors. </p>

Cationic steroid antimicrobials (CSAs or ceragenins) are a novel class of synthetic, cholic acid-based mimics of endogenous antimicrobial peptides. These small molecule compounds display broad bactericidal activity against gram-negative and gram-positive bacteria, potent ability against fungal pathogens, and cidal effects against drug resistant and multidrug resistant microbes. Implantable medical devices provide an abiotic surface upon which bacteria and fungi can accumulate--thereby leading to localized or systemic infection. We proposed that CSA antibiotics can be incorporated into medical device surface coatings which can be optimized for the active release or elution of the CSA compounds over time to prevent device-associated infections. This report will discuss the progress of developing and testing coating systems for 3 such devices: cardiac implantable electronic devices (CIED), silicone nasal splints, and breast tissue expanders. In the case of CIEDs, an envelope material containing CSA was created using bioresorbable polymers. We found that this envelope elutes CSA antibiotics and kills all surrounding bacteria or fungi in both planktonic and biofilm forms within 1 hour of exposure. We also developed a nasal splint coating which is directly adhered to the surface of the silicone splint. This coating system demonstrated more than 8 days of protective ability (full microbicidal activity to the detection limit) against Candida albicans, and reduced microbial growth of P. aeruginosa, Candida auris, and MRSA for approximately 6 days. Lastly, in the case of tissue expanders, we developed a layered coating which displays fully-reductive antimicrobial activity against MRSA for 8 days with reintroduction of bacteria every 24 hours. Additionally, this work will discuss our investigations into the secondary properties of ceragenin compounds. On the basis of studies which have demonstrated the pro-osteogenic properties of CSA, we probed the mechanism of this effect. We studied the potential effects of ceragenins on the proliferation, differentiation, and migration of bone-derived mesenchymal stem cells (MSCs). We have determined the absence of any positive proliferative effects of ceragenins on these cells; however, we have demonstrated the significant migration-promoting chemoattractant properties of CSA. In the case of CSA-13, we have observed up to a 400% increase in migration compared to the control. Also, we demonstrated that the P2X7 receptor is strongly implicated in the cellular mechanism of this effect. Our studies of the differentiation-promoting properties of CSA on MSCs have been largely inconclusive, but further investigations are proposed in this report. Lastly, this work includes a report on our investigations into the potential synergistic interactions between CSA-131/CSA-44 with amphotericin B or caspofungin, two commonly used antifungal agents.